66 results on '"M.-H. Hu"'
Search Results
2. [The application of continuous glucose monitoring in the management of hepatic glycogen storage disease]
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C Q, Du, H, Wei, C, Zhang, M, Zhang, M H, Hu, L, Hou, W, Wu, Y, Liang, and X P, Luo
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Blood Glucose ,Male ,Glucose ,Blood Glucose Self-Monitoring ,Humans ,Female ,Child ,Glycogen Storage Disease ,Retrospective Studies - Published
- 2021
3. [Research advances of fluid responsiveness in patients with circulatory failure]
- Author
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P F, Du, D H, Jiang, and M H, Hu
- Abstract
循环衰竭仍是临床最常见的急危重症,发生率与病死率一直居高不下,早期有效的液体复苏可以改善预后。但不同的患者对容量复苏的反应效果也存在差异,心肺功能不全的患者容量复苏后并不能增加其心输出量,反而会使其前负荷增加而诱发肺水肿,故评估容量反应性尤为重要。.
- Published
- 2019
4. A new paradigm for solving plasma fluid modeling equations.
- Author
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Chieh-Tsan Hung, M.-H. Hu, Jong-Shinn Wu, and Feng-Nan Hwang
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- 2007
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5. Gold nanoparticles functionalized with 2,6-dimercaptopurine for sensitive and selective colorimetric determination of cadmium(<scp>ii</scp>) in food, biological and environmental samples
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H. F. Zhu, L. L. Suo, L. H. Zhou, L. F. Ma, M. H. Hu, and W. H. Huang
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Detection limit ,Cadmium ,General Chemical Engineering ,010401 analytical chemistry ,General Engineering ,Analytical chemistry ,chemistry.chemical_element ,02 engineering and technology ,021001 nanoscience & nanotechnology ,01 natural sciences ,0104 chemical sciences ,Analytical Chemistry ,law.invention ,Metal ,chemistry ,law ,Colloidal gold ,visual_art ,visual_art.visual_art_medium ,Chelation ,Graphite ,Naked eye ,0210 nano-technology ,Atomic absorption spectroscopy ,Nuclear chemistry - Abstract
A simple, rapid and sensitive colorimetric method has been developed for the detection of Cd2+ using 2,6-dimercaptopurine-modified gold nanoparticles. In the presence of Cd2+, gold nanoparticles functionalized with 2,6-dimercaptopurine were aggregated via chelation between the metal ion and the ligand, accompanied by a color change from red to blue observed with the naked eye. Further, the solution of 2,6-dimercaptopurine-modified gold nanoparticles was monitored using a UV-Vis spectrometer. Under optimized conditions, good linearity varying from 0.75 to 3.0 μM was obtained with a correlation coefficient (R) of 0.996 along with a limit of detection of 32.7 nM. The recoveries were 88.0–112.0% in real samples, and the results agree well with those acquired by atomic absorption spectroscopy with a graphite furnace. The new approach was successfully applied to the determination of Cd2+ in milk, honey, lake water, serum, and urine samples.
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- 2017
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6. Progress on Developing a Multi-physics Simulation Platform: Rigorous Advanced Plasma Integration Testbed (RAPIT)
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Gary C. Cheng, Kuan-Lin Chen, Jong-Shinn Wu, C. C. Su, Richard Branam, Y. M. Lee, M. H. Hu, and M. F. Tzeng
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Computer science ,0103 physical sciences ,Testbed ,Systems engineering ,Plasma ,Dynamical simulation ,010303 astronomy & astrophysics ,01 natural sciences ,010305 fluids & plasmas - Published
- 2018
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7. [Adult peripheral primary neuroectodermal tumor: a case report and literature review]
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M H, Hu, F, Long, and S J, Jiang
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Adult ,Male ,Biopsy ,Quality of Life ,Humans ,Female ,Neuroectodermal Tumors, Primitive, Peripheral ,Thorax ,Prognosis - Published
- 2017
8. Using Films to Promote Cultural Awareness in an EFL Classroom
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M. H. Hu, Z. Y. Li, and Y. Y. Sun
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Pedagogy ,Psychology ,Cultural competence - Published
- 2017
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9. Treatment of polycystic ovarian syndrome with insulin resistance by insulin-sensitizer
- Author
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Q F Wu, M H Hu, H Shen, L Tian, and L Hu
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medicine.medical_specialty ,endocrine system diseases ,biology ,business.industry ,Cholesterol ,Insulin ,medicine.medical_treatment ,C-reactive protein ,Obstetrics and Gynecology ,medicine.disease ,Group B ,chemistry.chemical_compound ,Endocrinology ,Insulin resistance ,Reproductive Medicine ,chemistry ,Internal medicine ,medicine ,biology.protein ,Prospective cohort study ,business ,Body mass index ,Pioglitazone ,medicine.drug - Abstract
OBJECTIVE The aim of this study was to observe clinical curative effects of combination application of dimethylbiguanide and pioglitazone and single application of pioglitazone in patients with polycystic ovarian syndrome (PCOS) complicated with insulin resistance (IR). MATERIALS AND METHODS Forty cases of patients with PCOS complicated with IR were investigated, and 20 cases of infertile women without PCOS were taken as the control group. PCOS group was divided into group A and group B according to body mass index (BMI) to detect glucose and lipids metabolism indicators, C reactive protein (CRP), etc. There were 20 cases in group A (Pioglitazone) and 20 cases in group B (dimethylbiguanide and pioglitazone). After treatment for 12 weeks, changes of the above various indicators were compared. RESULTS After treatment, insulin resistance index and serum testosterone (T) of two groups patients with PCOS significantly reduced (p < 0.05). Compared to before treatment, BMI of group B significantly reduced (p < 0.05). For INS at two hours after treatment, group B reduced more significantly (p < 0.05). CONCLUSION The combination of dimethylbiguanide and pioglitazone was more effective for the treatment of PCOS complicated with IR than simple pioglitazone; chronic inflammation occurrence was possibly one of reasons for insulin sensitivity reduction of patients with PCOS.
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- 2014
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10. Parallel 2D Axisymmetric Fluid Modeling of CF4Discharge in an Inductively Coupled Plasma Source During SiO2Etching
- Author
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C. T. Hung, Chung Hua Chiang, M.-H. Hu, Yuan Ming Chiu, Feng Nan Hwang, and Jong-Shinn Wu
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chemistry.chemical_compound ,Polymers and Plastics ,Etching (microfabrication) ,Chemistry ,Etching rate ,Rotational symmetry ,Analytical chemistry ,Tetrafluoromethane ,Substrate (electronics) ,Plasma ,Inductively coupled plasma ,Condensed Matter Physics ,Fluid modeling - Abstract
A parallel 2D axisymmetric plasma fluid modeling for an inductively coupled plasma source with tetrafluoromethane precursor is reported. In total, 32 species with 96 gas-phase and 27 surface reactions with site-balance equations are considered. The predicted results of major species densities are in reasonable agreement with reported experiments. The etching products, e.g. SiFx and O2, are found to be appreciable (� 10%) compared to the precursor near the substrate. The predicted density trends, such as CFx þ and CFx (x ¼1‐3), are also consistent with reported experiments. Finally, the predicted etching rate on the SiO2 substrate is presented and discussed in detail.
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- 2014
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11. [The application of the three-step approach based on the regional distribution of hepatic vessel in laparoscopic hemihepatectomy]
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X M, Wang, W D, Sun, M H, Hu, G N, Wang, Y Q, Jiang, X S, Fang, and M, Han
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Treatment Outcome ,Liver ,Blood Loss, Surgical ,Hepatectomy ,Humans ,Laparoscopy ,Hepatic Veins ,Length of Stay ,Retrospective Studies - Abstract
To investigate the clinical significance of the three-step approach in laparoscopic hemihepatectomy.A total of 32 patients received laparoscopic hemihepatectomy with the three-step approach in Yijishan Hospital affiliated to Wannan Medical College between Aug 2013 and Oct 2015. All patients underwent thin slice CT scan and hemihepatectomy was imitated with the imagic explorer, preoperatively. The vessel distribution was observed at the section and the three-step approach was used in the hemihepatectomy. Pre- and post-operative data were collected and analyzed retrospectively.The length of middle hepatic vein (MHV) was (59.1±12.9) mm and the number of branchs to the left and right lobe were 3.07±0.78 and 3.11±0.64 respectively. The distance between the first branch of MHV and the diaphragmatic surface was (28.07±3.74) mm and the distance between MHV and the visceral surface was (14.4±4.3) mm. The laparoscopic surgeries (left hemihepatectomy in 28 and right hemihepatectomy in 4) were performed successfully in all cases with the three-step approach, without any conversion to the open surgeries. The operation time was (165±42) min in left hemihepatectomy and (305±50) min in right hemihepatectomy. The intraoperative blood loss was (242±65) ml in left hemihepatectomy and (695±122)ml in right hemihepatectomy. All the patients recovered well without severe complications except for bile leakage in 3 patients who were cured with drainage. The postoperative hospital stay was (7.96±1.8) d.the distribution of vessel is regional at the section of hemihepatectomy and the three-step approach based on this feature is safe and effective in laparoscopic hemihepatectomy, which can shorten the operation time and reduce the difficulty of operation.
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- 2016
12. Posterodorsal Medial Amygdala Mediates Tail-Pinch Induced Food Intake in Female Rats
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M H, Hu, Z, Bashir, X F, Li, and K T, O'Byrne
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food intake ,Corticomedial Nuclear Complex ,Estradiol ,Corticotropin-Releasing Hormone ,Ovariectomy ,Original Articles ,amygdala ,CRF ,Receptors, Corticotropin-Releasing Hormone ,Peptide Fragments ,Rats, Sprague-Dawley ,Eating ,stress ,Physical Stimulation ,comfort eating ,Animals ,Female ,Original Article ,Stress, Psychological - Abstract
Comfort eating during periods of stress is a common phenomenon observed in both animals and humans. However, the underlying mechanisms of stress‐induced food intake remain elusive. The amygdala plays a central role in higher‐order emotional processing and the posterodorsal subnucleus of the medial amygdala (MePD), in particular, is involved in food intake. Extra‐hypothalamic corticotrophin‐releasing factor (CRF) is well recognised for mediating behavioural responses to stress. To explore the possible role of amygdala CRF receptor activation in stress‐induced food intake, we evaluated whether a stressor such as tail‐pinch, which reliably induces food intake, would fail to do so in animals bearing bilateral neurotoxic lesions of the MePD. Our results showed that ibotenic acid induced lesions of the MePD markedly reduced tail‐pinch induced food intake in ovariectomised, 17β‐oestradiol replaced rats. In addition, intra‐MePD (right side only) administration of CRF (0.002 or 0.02 ng) via chronically implanted cannulae resulted in a dose‐dependent increase in food intake, although higher doses of 0.2 and 2 ng CRF had less effect, producing a bell shaped curve. Furthermore, intra‐MePD (bilateral) administration of the CRF receptor antagonist, astressin (0.3 μg per side) effectively blocked tail‐pinch induced food intake. These data suggest that the MePD is involved in stress‐induced food intake and that the amygdala CRF system may be a mediator of comfort eating.
- Published
- 2016
13. Development of a parallelized 2D/2D-axisymmetric Navier–Stokes equation solver for all-speed gas flows
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Jong-Shinn Wu, M.-H. Hu, and Yen-Sen Chen
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Finite volume method ,General Computer Science ,Preconditioner ,business.industry ,MathematicsofComputing_NUMERICALANALYSIS ,General Engineering ,Solver ,Computational fluid dynamics ,Computer Science::Numerical Analysis ,Compressible flow ,Physics::Fluid Dynamics ,Classical mechanics ,Biconjugate gradient stabilized method ,Compressibility ,Applied mathematics ,Navier–Stokes equations ,business ,Mathematics - Abstract
A parallelized 2D/2D-axisymmetric pressure-based, extended SIMPLE finite-volume Navier–Stokes equation solver using Cartesians grids has been developed for simulating compressible, viscous, heat conductive and rarefied gas flows at all speeds with conjugate heat transfer. The discretized equations are solved by the parallel Krylov–Schwarz (KS) algorithm, in which the ILU and BiCGStab or GMRES scheme are used as the preconditioner and linear matrix equation solver, respectively. Developed code was validated by comparing previous published simulations wherever available for both low- and high-speed gas flows. Parallel performance for a typical 2D driven cavity problem is tested on the IBM-1350 at NCHC of Taiwan up to 32 processors. Future applications of this code are discussed briefly at the end.
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- 2011
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14. Experimental research on the high accuracy mass determination between stainless and silicon sphere mass standards
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M. H. Hu, Y. Zhang, K. Jiao, J. Wang, R. L. Zhong, Z. Han, and C. Q. Cai
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History ,Materials science ,Silicon ,chemistry ,Nuclear engineering ,chemistry.chemical_element ,Experimental research ,Computer Science Applications ,Education - Published
- 2018
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15. Nanometer-designed Al/SiC periodic multilayers: characterization by a multi-technique approach
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K. Le Guen, C. Hecquet, E. Meltchakov, Franck Delmotte, Jean-Michel André, M.-H. Hu, Philippe Jonnard, and Anouk Galtayries
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Materials science ,business.industry ,Extreme ultraviolet lithography ,Refractory metals ,Mineralogy ,Surfaces and Interfaces ,General Chemistry ,Surface finish ,Sputter deposition ,Condensed Matter Physics ,Surfaces, Coatings and Films ,X-ray reflectivity ,Chemical state ,chemistry.chemical_compound ,chemistry ,Materials Chemistry ,Silicon carbide ,Optoelectronics ,Nanometre ,business - Abstract
Nanometer-thick Al/SiC periodic multilayers, designed for the Extreme Ultra Violet (EUV) range, have been characterized by different techniques dedicated to such thin multilayers (each between 4 and 10 nm thick). In order to decrease the roughness and to improve the optical performances of the stacks, an ultrathin (2 nm) refractory metal layer has also been introduced, thus making Al/W/SiC and Al/Mo/SiC multilayer systems with three layers in period. The samples are deposited by magnetron sputtering. The stacks have a period ranging between 16 and 18 nm. Time-of-Flight SIMS (ToF-SIMS) is used here to determine the depth profiles of the different elements present within the multilayers. It is observed that the interfaces of the Al/W/SiC and Al/Mo/SiC multilayers are sharper than those of the Al/SiC system. X-ray emission spectroscopy (XES) is used to identify the chemical state of the Al and Si atoms within the multilayers and to check if there is any interfacial compound. The results show that there is no interaction between the Al and SiC layers leading to the formation of an interfacial compound. The results are confirmed by X-ray reflectivity (XRR) measurements. They show that the Al/SiC multilayers present large interfacial roughnesses, but the Al/W/SiC and Al/Mo/SiC multilayers have the lower roughness values. Copyright © 2010 John Wiley & Sons, Ltd.
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- 2010
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16. Full-scale vertical drop test and numerical simulation of a crashworthy helicopter seat/occupant system
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Jian-li Yang, M. H. Hu, and Daijun Hu
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Engineering ,Computer simulation ,business.industry ,Mechanical Engineering ,Full scale ,Poison control ,Transportation ,Structural engineering ,Drop test ,Industrial and Manufacturing Engineering ,Energy absorption ,Crashworthiness ,Finite element code ,business ,Simulation ,Test data - Abstract
A full-scale vertical drop test of a crashworthy helicopter seat/occupant system was performed to evaluate the energy-absorption capability of a new-type crashworthy seat, and to study its influence under impact conditions on the occupant responses and human tolerance. In order to gain a better understanding of the physics behind the impact, a numerical simulation of the crashworthy seat structure was carried out and the simulation results were compared with the test data. In the numerical simulation, a full-scale three-dimensional multi-rigid body model of the seat/occupant structure was developed using a commercial code, Mathematical Dynamic Model (MADYMO), associated with non-linear finite element code (LS-DYNA). Emphasis of the numerical simulation was placed on predicting the dynamic response of seat/occupant system, including the occupant motion that may lead to injuries due to intensive whipping of human body, the acceleration–time histories and the energy-absorbing behaviour of the inversion tubes...
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- 2009
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17. Generating landslide density heatmaps for rapid detection using open-access satellite radar data in Google Earth Engine
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A. L. Handwerger, M.-H. Huang, S. Y. Jones, P. Amatya, H. R. Kerner, and D. B. Kirschbaum
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Environmental technology. Sanitary engineering ,TD1-1066 ,Geography. Anthropology. Recreation ,Environmental sciences ,GE1-350 ,Geology ,QE1-996.5 - Abstract
Rapid detection of landslides is critical for emergency response, disaster mitigation, and improving our understanding of landslide dynamics. Satellite-based synthetic aperture radar (SAR) can be used to detect landslides, often within days of a triggering event, because it penetrates clouds, operates day and night, and is regularly acquired worldwide. Here we present a SAR backscatter change approach in the cloud-based Google Earth Engine (GEE) that uses multi-temporal stacks of freely available data from the Copernicus Sentinel-1 satellites to generate landslide density heatmaps for rapid detection. We test our GEE-based approach on multiple recent rainfall- and earthquake-triggered landslide events. Our ability to detect surface change from landslides generally improves with the total number of SAR images acquired before and after a landslide event, by combining data from both ascending and descending satellite acquisition geometries and applying topographic masks to remove flat areas unlikely to experience landslides. Importantly, our GEE approach does not require downloading a large volume of data to a local system or specialized processing software, which allows the broader hazard and landslide community to utilize and advance these state-of-the-art remote sensing data for improved situational awareness of landslide hazards.
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- 2022
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18. Treatment of polycystic ovarian syndrome with insulin resistance by insulin-sensitizer
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L, Hu, H, Shen, Q F, Wu, L, Tian, and M H, Hu
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Adult ,Blood Glucose ,Adolescent ,Body Mass Index ,Young Adult ,Hyperinsulinism ,Homeostasis ,Humans ,Hypoglycemic Agents ,Insulin ,Testosterone ,Obesity ,Prospective Studies ,Triglycerides ,Pioglitazone ,Cholesterol, HDL ,Cholesterol, LDL ,Fasting ,Metformin ,C-Reactive Protein ,Drug Therapy, Combination ,Female ,Thiazolidinediones ,Insulin Resistance ,Infertility, Female ,Polycystic Ovary Syndrome - Abstract
The aim of this study was to observe clinical curative effects of combination application of dimethylbiguanide and pioglitazone and single application of pioglitazone in patients with polycystic ovarian syndrome (PCOS) complicated with insulin resistance (IR).Forty cases of patients with PCOS complicated with IR were investigated, and 20 cases of infertile women without PCOS were taken as the control group. PCOS group was divided into group A and group B according to body mass index (BMI) to detect glucose and lipids metabolism indicators, C reactive protein (CRP), etc. There were 20 cases in group A (Pioglitazone) and 20 cases in group B (dimethylbiguanide and pioglitazone). After treatment for 12 weeks, changes of the above various indicators were compared.After treatment, insulin resistance index and serum testosterone (T) of two groups patients with PCOS significantly reduced (p0.05). Compared to before treatment, BMI of group B significantly reduced (p0.05). For INS at two hours after treatment, group B reduced more significantly (p0.05).The combination of dimethylbiguanide and pioglitazone was more effective for the treatment of PCOS complicated with IR than simple pioglitazone; chronic inflammation occurrence was possibly one of reasons for insulin sensitivity reduction of patients with PCOS.
- Published
- 2014
19. A Bayesian Analysis of Steam Generator Tube Wall Emissivity for Heat Treatment
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M. H. Hu
- Subjects
Materials science ,Mechanical Engineering ,Nuclear engineering ,Emissivity ,Boiler (power generation) ,General Physics and Astronomy ,Thermodynamics - Published
- 1998
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20. Characterization of multilayers and their interlayers: application to Co-based systems
- Author
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J.-M. André, P. Jonnard, K. Le Guen, Z. S. Wang, Jingtao Zhu, M.-H. Hu, Christian Meny, Laboratoire de Chimie Physique - Matière et Rayonnement (LCPMR), Centre National de la Recherche Scientifique (CNRS)-Institut de Chimie du CNRS (INC)-Université Pierre et Marie Curie - Paris 6 (UPMC), Institute of Precision Optical Engineering [Shangai] (IPOE), Tongji University, Institut de Physique et Chimie des Matériaux de Strasbourg (IPCMS), Université de Strasbourg (UNISTRA)-Matériaux et nanosciences d'Alsace (FMNGE), Institut de Chimie du CNRS (INC)-Université de Strasbourg (UNISTRA)-Université de Haute-Alsace (UHA) Mulhouse - Colmar (Université de Haute-Alsace (UHA))-Institut National de la Santé et de la Recherche Médicale (INSERM)-Centre National de la Recherche Scientifique (CNRS)-Institut de Chimie du CNRS (INC)-Université de Strasbourg (UNISTRA)-Université de Haute-Alsace (UHA) Mulhouse - Colmar (Université de Haute-Alsace (UHA))-Institut National de la Santé et de la Recherche Médicale (INSERM)-Centre National de la Recherche Scientifique (CNRS)-Centre National de la Recherche Scientifique (CNRS)-Réseau nanophotonique et optique, Centre National de la Recherche Scientifique (CNRS)-Université de Strasbourg (UNISTRA)-Université de Haute-Alsace (UHA) Mulhouse - Colmar (Université de Haute-Alsace (UHA))-Centre National de la Recherche Scientifique (CNRS)-Université de Strasbourg (UNISTRA), Part of this work was performed within the frame- work of the ANR-NSFC COBMUL project (ANR-10- INTB-902-01 and NSFC11061130549)., ANR-10-INTB-0902,COBMUL,Nouveaux matériaux multicouches à base de cobalt pour applications optiques dans l'extrême ultra-violet(2010), Université Pierre et Marie Curie - Paris 6 (UPMC)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS), Université de Strasbourg (UNISTRA)-Centre National de la Recherche Scientifique (CNRS)-Matériaux et Nanosciences Grand-Est (MNGE), Université de Strasbourg (UNISTRA)-Université de Haute-Alsace (UHA) Mulhouse - Colmar (Université de Haute-Alsace (UHA))-Institut National de la Santé et de la Recherche Médicale (INSERM)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS)-Université de Strasbourg (UNISTRA)-Université de Haute-Alsace (UHA) Mulhouse - Colmar (Université de Haute-Alsace (UHA))-Institut National de la Santé et de la Recherche Médicale (INSERM)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS)-Réseau nanophotonique et optique, and Université de Strasbourg (UNISTRA)-Université de Haute-Alsace (UHA) Mulhouse - Colmar (Université de Haute-Alsace (UHA))-Centre National de la Recherche Scientifique (CNRS)-Université de Strasbourg (UNISTRA)-Centre National de la Recherche Scientifique (CNRS)
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spectroscopy ,Materials science ,Extreme ultraviolet lithography ,Nanotechnology ,Surface finish ,01 natural sciences ,010309 optics ,Multilayer X ray mirrors ,Optics ,Stack (abstract data type) ,0103 physical sciences ,Electrical and Electronic Engineering ,[PHYS.PHYS.PHYS-OPTICS]Physics [physics]/Physics [physics]/Optics [physics.optics] ,business.industry ,[CHIM.MATE]Chemical Sciences/Material chemistry ,Atomic and Molecular Physics, and Optics ,Electronic, Optical and Magnetic Materials ,Characterization (materials science) ,Secondary ion mass spectrometry ,Chemical state ,Transmission electron microscopy ,Extreme ultraviolet ,[PHYS.COND.CM-GEN]Physics [physics]/Condensed Matter [cond-mat]/Other [cond-mat.other] ,Optoelectronics ,interface ,business ,X-ray and EUV Reflectivity - Abstract
This paper was published in Chinese Optics Letters and is made available as an electronic reprint with the permission of OSA. The paper can be found at the following URL on the OSA website: http://www.col.org.cn/abstract.aspx?id=COL201311S10601-04. Systematic or multiple reproduction or distribution to multiple locations via electronic or other means is prohibited and is subject to penalties under law.; International audience; We use complementary analysis techniques to determine the structure of nanometric periodic multilayers and particularly their interfaces. We focus on Co-based multilayer which can be used as efficient optical component in the extreme ultraviolet (EUV) range. The samples are characterized using reflectivity measurements in order to determine the thickness and roughness of the various layers, X-ray emission and nuclear magnetic resonance (NMR) spectroscopies to identify the chemical state of the atoms present within the stack and know if they interdiffuse. Results are validated through the use of destructive techniques such as transmission electron microscopy or secondary ion mass spectrometry.
- Published
- 2013
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21. Parallel 2-D simulation of atmospheric-pressure plasma jet accelerated by a temporal multi-scale model
- Author
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M.-H. Hu, Jong-Shinn Wu, Chin-Te Hung, and K. M. Lin
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Coupling ,Physics ,Jet (fluid) ,Fluid dynamics ,Atmospheric-pressure plasma ,Mechanics ,Plasma ,Atmospheric model ,Scale model ,Computational physics ,Electric discharge in gases - Abstract
Summary form only given. For low-pressure gas discharges, fluid modeling without considering the fluid dynamics is often considered to be valid. However, as the pressure rises, fluid dynamics becomes important in affecting the gas discharges. Therefore, a thorough simulation of atmospheric-pressure plasma jets (APPJ) needs to consider two parts, the gas flow model (GFM) and the plasma fluid model (PFM). There have been very few studies in the literature which have focused on this regard.1−4 The complete simulation of APPJ coupling the fluid dynamics and gas discharge often takes from weeks up to months of runtime. Specifically speaking, the part of PFM takes generally more than 90% of the overall runtime for the simulation of APPJ. In other word, the bottleneck for speeding up the APPJ simulation is to shorten the runtime consumed by the part of PFM.
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- 2012
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22. Enhancement of radical generation in a round helium atmospheric-pressure plasma jet by an on-time modulated power source
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Jong-Shinn Wu, Chih Tung Liu, K. M. Lin, Yi Wei Yang, Ching Jung Wu, M.-H. Hu, Zong-Hong Lin, and K.-C. Liao
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Materials science ,Silicon ,business.industry ,chemistry.chemical_element ,Atmospheric-pressure plasma ,Pipe flow ,Volumetric flow rate ,chemistry ,Optical Emission Spectrometer ,Electrode ,Optoelectronics ,Gas composition ,business ,Helium - Abstract
Summary form only given. Atmospheric-pressure plasma jet (APPJ) has attracted tremendous attention in the past decade mainly due to its low cost and flexibility without the use of expensive vacuum equipment. It has found numerous applications such as surface cleaning, surface modification, thin-film deposition and recently biomedical applications that may include sterilization, blood coagulation, cell growth enhancement and wound healing, to name a few.In this paper, a round APPJ device is developed and tested. This APPJ consists of four parts: a silicon tube, a stainless steel tube, an aluminum tube and an aluminum ring. Powered electrode, which includes a stainless steel tube and an aluminum tube, is placed inside the silicon tube. The grounded electrode (aluminum ring) is wrapped around at the surface of silicon tube with some proper distance from the powered electrode (aluminum tube) inside the silicon tube. An AC power source of 60 W with a frequency of 25 kHz is applied to this APPJ with different high-voltage on-time settings. Optical emission spectrometer (OES) and a mercury thermometer are used for measuring the OES and gas temperature in the jet region at various downstream locations, which is important for biomedical applications. Helium (99.99%) is used as the working gas with a flow rate of 4 slm. Gas composition analysis using gas chromatography (GC) shows that an appreciable amount of impurities including oxygen and nitrogen (more than 20ppm) is found. Corresponding Reynolds number based on the average speed and inner diameter of the silicon tube is 1,392, which is a typical laminar pipe flow.
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- 2012
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23. The role of GABAergic signalling in stress-induced suppression of gonadotrophin-releasing hormone pulse generator frequency in female rats
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Y S, Lin, X F, Li, B, Shao, M H, Hu, A L R, Goundry, A, Jeyaram, S L, Lightman, and K T, O'Byrne
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Ovariectomy ,Luteinizing Hormone ,Bicuculline ,Preoptic Area ,Rats ,GABA Antagonists ,Gonadotropin-Releasing Hormone ,Rats, Sprague-Dawley ,Organophosphorus Compounds ,Stress, Physiological ,Animals ,Female ,gamma-Aminobutyric Acid ,Signal Transduction - Abstract
Stress exerts profound inhibitory effects on reproductive function by suppressing the pulsatile release of gonadotrophin-releasing hormone (GnRH) and therefore luteinising hormone (LH). This effect is mediated in part via the corticotrophin-releasing factor (CRF) system, although another potential mechanism is via GABAergic signalling within the medial preoptic area (mPOA) because this has known inhibitory influences on the GnRH pulse generator and shows increased activity during stress. In the present study, we investigated the role of the preoptic endogenous GABAergic system in stress-induced suppression of the GnRH pulse generator. Ovariectomised oestradiol-replaced rats were implanted with bilateral and unilateral cannulae targeting toward the mPOA and lateral cerebral ventricle, respectively; blood samples (25 μl) were taken via chronically implanted cardiac catheters every 5 min for 6 h for the measurement of LH pulses. Intra-mPOA administration of the specific GABA(A) receptor antagonist, bicuculline (0.2 pmol each side, three times at 20-min intervals) markedly attenuated the inhibitory effect of lipopolysaccharide (LPS; 25 μg/kg i.v.) but not restraint (1 h) stress on pulsatile LH secretion. By contrast, restraint but not LPS stress-induced suppression of LH pulse frequency was reversed by application of the selective GABA(B) receptor antagonist, CGP-35348, into the mPOA (1.5 nmol each side, three times at 20-min intervals). However, intra-mPOA application of either bicuculline or CGP-35348 attenuated the inhibitory effect of CRF (1 nmol i.c.v.) on the pulsatile LH secretion. These data indicate a pivotal and differential role of endogenous GABAergic signalling in the mPOA with respect to mediating psychological and immunological stress-induced suppression of the GnRH pulse generator.
- Published
- 2011
24. Investigation of the thermal stability of Mg/Co periodic multilayers for EUV applications
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Haochuan Li, Angela Giglia, Nicola Mahne, S.-K. Zhou, Michael Walls, Jean-Michel André, K. Le Guen, Philippe Jonnard, Jie Zhu, M.-H. Hu, Zhanshan Wang, Imène Esteve, Stefano Nannarone, Christian Meny, Laboratoire de Chimie Physique - Matière et Rayonnement ( LCPMR ), Université Pierre et Marie Curie - Paris 6 ( UPMC ) -Centre National de la Recherche Scientifique ( CNRS ), Institute of Precision Optical Engineering. ( IPOE ), Tongji University, Institut de Physique et Chimie des Matériaux de Strasbourg ( IPCMS ), Université de Strasbourg ( UNISTRA ) -Centre National de la Recherche Scientifique ( CNRS ) -Matériaux et nanosciences d'Alsace, Université de Strasbourg ( UNISTRA ) -Université de Haute-Alsace (UHA) Mulhouse - Colmar ( Université de Haute-Alsace (UHA) ) -Institut National de la Santé et de la Recherche Médicale ( INSERM ) -Centre National de la Recherche Scientifique ( CNRS ) -Université de Strasbourg ( UNISTRA ) -Université de Haute-Alsace (UHA) Mulhouse - Colmar ( Université de Haute-Alsace (UHA) ) -Institut National de la Santé et de la Recherche Médicale ( INSERM ) -Centre National de la Recherche Scientifique ( CNRS ) -Réseau nanophotonique et optique, Université de Strasbourg ( UNISTRA ) -Université de Haute-Alsace (UHA) Mulhouse - Colmar ( Université de Haute-Alsace (UHA) ) -Centre National de la Recherche Scientifique ( CNRS ) -Université de Strasbourg ( UNISTRA ), CNR - Istituto Officina dei Materiali ( IOM ), Consiglio Nazionale delle Ricerche [Roma] ( CNR ), Institut de minéralogie et de physique des milieux condensés ( IMPMC ), Université Pierre et Marie Curie - Paris 6 ( UPMC ) -IPG PARIS-Université Paris Diderot - Paris 7 ( UPD7 ) -Centre National de la Recherche Scientifique ( CNRS ), Laboratoire de Physique des Solides ( LPS ), Université Paris-Sud - Paris 11 ( UP11 ) -Centre National de la Recherche Scientifique ( CNRS ), Laboratoire de Chimie Physique - Matière et Rayonnement (LCPMR), Université Pierre et Marie Curie - Paris 6 (UPMC)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS), Institute of Precision Optical Engineering [Shangai] (IPOE), Institut de Physique et Chimie des Matériaux de Strasbourg (IPCMS), Université de Strasbourg (UNISTRA)-Centre National de la Recherche Scientifique (CNRS)-Matériaux et Nanosciences Grand-Est (MNGE), Université de Strasbourg (UNISTRA)-Université de Haute-Alsace (UHA) Mulhouse - Colmar (Université de Haute-Alsace (UHA))-Institut National de la Santé et de la Recherche Médicale (INSERM)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS)-Université de Strasbourg (UNISTRA)-Université de Haute-Alsace (UHA) Mulhouse - Colmar (Université de Haute-Alsace (UHA))-Institut National de la Santé et de la Recherche Médicale (INSERM)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS)-Réseau nanophotonique et optique, Université de Strasbourg (UNISTRA)-Université de Haute-Alsace (UHA) Mulhouse - Colmar (Université de Haute-Alsace (UHA))-Centre National de la Recherche Scientifique (CNRS)-Université de Strasbourg (UNISTRA)-Centre National de la Recherche Scientifique (CNRS), CNR Istituto Officina dei Materiali (IOM), National Research Council of Italy | Consiglio Nazionale delle Ricerche (CNR), Institut de minéralogie et de physique des milieux condensés (IMPMC), Université Pierre et Marie Curie - Paris 6 (UPMC)-Université Paris Diderot - Paris 7 (UPD7)-Institut de Physique du Globe de Paris (IPG Paris)-Centre National de la Recherche Scientifique (CNRS), Laboratoire de Physique des Solides (LPS), Université Paris-Sud - Paris 11 (UP11)-Centre National de la Recherche Scientifique (CNRS), Centre National de la Recherche Scientifique (CNRS)-Institut de Chimie du CNRS (INC)-Université Pierre et Marie Curie - Paris 6 (UPMC), Université de Strasbourg (UNISTRA)-Matériaux et nanosciences d'Alsace (FMNGE), Institut de Chimie du CNRS (INC)-Université de Strasbourg (UNISTRA)-Université de Haute-Alsace (UHA) Mulhouse - Colmar (Université de Haute-Alsace (UHA))-Institut National de la Santé et de la Recherche Médicale (INSERM)-Centre National de la Recherche Scientifique (CNRS)-Institut de Chimie du CNRS (INC)-Université de Strasbourg (UNISTRA)-Université de Haute-Alsace (UHA) Mulhouse - Colmar (Université de Haute-Alsace (UHA))-Institut National de la Santé et de la Recherche Médicale (INSERM)-Centre National de la Recherche Scientifique (CNRS)-Centre National de la Recherche Scientifique (CNRS)-Réseau nanophotonique et optique, Centre National de la Recherche Scientifique (CNRS)-Université de Strasbourg (UNISTRA)-Université de Haute-Alsace (UHA) Mulhouse - Colmar (Université de Haute-Alsace (UHA))-Centre National de la Recherche Scientifique (CNRS)-Université de Strasbourg (UNISTRA), Consiglio Nazionale delle Ricerche [Roma] (CNR), Université Pierre et Marie Curie - Paris 6 (UPMC)-IPG PARIS-Université Paris Diderot - Paris 7 (UPD7)-Centre National de la Recherche Scientifique (CNRS), and Centre National de la Recherche Scientifique (CNRS)-Université Paris-Sud - Paris 11 (UP11)
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Materials science ,Annealing (metallurgy) ,Scanning electron microscope ,Extreme ultraviolet lithography ,Mg ,Analytical chemistry ,FOS: Physical sciences ,02 engineering and technology ,01 natural sciences ,Co ,0103 physical sciences ,Scanning transmission electron microscopy ,General Materials Science ,Thermal stability ,Emission spectrum ,010302 applied physics ,Condensed Matter - Materials Science ,[PHYS.PHYS.PHYS-OPTICS]Physics [physics]/Physics [physics]/Optics [physics.optics] ,electron energy loss spectroscopy ,[ PHYS.PHYS.PHYS-OPTICS ] Physics [physics]/Physics [physics]/Optics [physics.optics] ,multilayer ,Electron energy loss spectroscopy ,Materials Science (cond-mat.mtrl-sci) ,General Chemistry ,x-ray emission spectroscopy ,[ PHYS.COND.CM-GEN ] Physics [physics]/Condensed Matter [cond-mat]/Other [cond-mat.other] ,EUV reflectivity ,021001 nanoscience & nanotechnology ,3. Good health ,nuclear magnetism resonance spectroscopy ,Condensed Matter - Other Condensed Matter ,Chemical state ,[PHYS.COND.CM-GEN]Physics [physics]/Condensed Matter [cond-mat]/Other [cond-mat.other] ,scanning transmission electron microscopy ,interface ,annealing ,0210 nano-technology ,scanning electron microscopy ,Physics - Optics ,Other Condensed Matter (cond-mat.other) ,Optics (physics.optics) - Abstract
We present the results of the characterization of Mg/Co periodic multilayers and their thermal stability for the EUV range. The annealing study is performed up to a temperature of 400\degree C. Images obtained by scanning transmission electron microscopy and electron energy loss spectroscopy clearly show the good quality of the multilayer structure. The measurements of the EUV reflectivity around 25 nm (~49 eV) indicate that the reflectivity decreases when the annealing temperature increases above 300\degreeC. X-ray emission spectroscopy is performed to determine the chemical state of the Mg atoms within the Mg/Co multilayer. Nuclear magnetic resonance used to determine the chemical state of the Co atoms and scanning electron microscopy images of cross sections of the Mg/Co multilayers reveal changes in the morphology of the stack from an annealing temperature of 305\degreee;C. This explains the observed reflectivity loss., Comment: Published in Applied Physics A: Materials Science \& Processing Published at http://www.springerlink.com.chimie.gate.inist.fr/content/6v396j6m56771r61/ 21 pages
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- 2011
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25. Characterization of EUV periodic multilayers
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Evgueni Meltchakov, Jean-Michel André, Philippe Jonnard, Franck Delmotte, K. Le Guen, Anouk Galtayries, Zhanshan Wang, M.-H. Hu, Christophe Hecquet, Jingtao Zhu, Christian Meny, Laboratoire de Chimie Physique - Matière et Rayonnement (LCPMR), Université Pierre et Marie Curie - Paris 6 (UPMC)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS), Institute of Precision Optical Engineering [Shangai] (IPOE), Tongji University, Laboratoire de Physico-Chimie des Surfaces (LPCS), Ecole Nationale Supérieure de Chimie de Paris - Chimie ParisTech-PSL (ENSCP), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS), Institut de Physique et Chimie des Matériaux de Strasbourg (IPCMS), Université de Strasbourg (UNISTRA)-Centre National de la Recherche Scientifique (CNRS)-Matériaux et nanosciences d'Alsace (FMNGE), Institut de Chimie du CNRS (INC)-Université de Strasbourg (UNISTRA)-Université de Haute-Alsace (UHA) Mulhouse - Colmar (Université de Haute-Alsace (UHA))-Institut National de la Santé et de la Recherche Médicale (INSERM)-Centre National de la Recherche Scientifique (CNRS)-Institut de Chimie du CNRS (INC)-Université de Strasbourg (UNISTRA)-Université de Haute-Alsace (UHA) Mulhouse - Colmar (Université de Haute-Alsace (UHA))-Institut National de la Santé et de la Recherche Médicale (INSERM)-Centre National de la Recherche Scientifique (CNRS)-Réseau nanophotonique et optique, Centre National de la Recherche Scientifique (CNRS)-Université de Strasbourg (UNISTRA)-Université de Haute-Alsace (UHA) Mulhouse - Colmar (Université de Haute-Alsace (UHA))-Centre National de la Recherche Scientifique (CNRS)-Université de Strasbourg (UNISTRA), Laboratoire Charles Fabry de l'Institut d'Optique / Scop, Laboratoire Charles Fabry de l'Institut d'Optique (LCFIO), Centre National de la Recherche Scientifique (CNRS)-Institut d'Optique Graduate School (IOGS)-Université Paris-Sud - Paris 11 (UP11)-Centre National de la Recherche Scientifique (CNRS)-Institut d'Optique Graduate School (IOGS)-Université Paris-Sud - Paris 11 (UP11), Université de Strasbourg (UNISTRA)-Centre National de la Recherche Scientifique (CNRS)-Matériaux et Nanosciences Grand-Est (MNGE), Université de Strasbourg (UNISTRA)-Université de Haute-Alsace (UHA) Mulhouse - Colmar (Université de Haute-Alsace (UHA))-Institut National de la Santé et de la Recherche Médicale (INSERM)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS)-Université de Strasbourg (UNISTRA)-Université de Haute-Alsace (UHA) Mulhouse - Colmar (Université de Haute-Alsace (UHA))-Institut National de la Santé et de la Recherche Médicale (INSERM)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS)-Réseau nanophotonique et optique, Université de Strasbourg (UNISTRA)-Université de Haute-Alsace (UHA) Mulhouse - Colmar (Université de Haute-Alsace (UHA))-Centre National de la Recherche Scientifique (CNRS)-Université de Strasbourg (UNISTRA)-Centre National de la Recherche Scientifique (CNRS), and Université Paris-Sud - Paris 11 (UP11)-Institut d'Optique Graduate School (IOGS)-Centre National de la Recherche Scientifique (CNRS)-Université Paris-Sud - Paris 11 (UP11)-Institut d'Optique Graduate School (IOGS)-Centre National de la Recherche Scientifique (CNRS)
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010302 applied physics ,extreme UV ,[PHYS.PHYS.PHYS-OPTICS]Physics [physics]/Physics [physics]/Optics [physics.optics] ,Materials science ,multilayers ,Analytical chemistry ,02 engineering and technology ,[CHIM.MATE]Chemical Sciences/Material chemistry ,Sputter deposition ,021001 nanoscience & nanotechnology ,01 natural sciences ,Spectral line ,Ion ,NMR spectra database ,Chemical state ,x-ray ,Extreme ultraviolet ,[PHYS.COND.CM-GEN]Physics [physics]/Condensed Matter [cond-mat]/Other [cond-mat.other] ,0103 physical sciences ,interdiffusion ,Emission spectrum ,0210 nano-technology ,Spectroscopy ,roughness - Abstract
13 pages; International audience; Nanometric Co/Mg, Co/Mg/B4C, Al/SiC and Al/Mo/SiC periodic multilayers deposited by magnetron sputtering are studied in order to correlate their optical performances in the extreme ultraviolet (EUV) range to their structural quality. To that purpose, our recently developed methodology based on high resolution x-ray emission spectroscopy (XES) and x-ray and EUV reflectometry is now extended to nuclear magnetic resonance (NMR) spectroscopy and time-of-flight secondary ions mass spectrometry (ToF-SIMS). The analysis of the Co Lalpha,beta and Mg Kbeta emission spectra shows that the Co and Mg atoms within the multilayers are in a chemical state equivalent to that of the atoms in the pure Co and Mg references respectively. But NMR spectra give evidence for a reaction between Co atoms and B and/or C atoms from B4C. The Al and Si Kbeta emission spectra do not reveal the formation of an interfacial compound in Al/SiC and Al/Mo/SiC. Only the roughness limits the optical quality of Al/SiC. The comparative analysis of the ToF-SIMS spectra of Al/SiC and Al/Mo/SiC indicates that the structural quality is enhanced when Mo is introduced within the stack.
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- 2011
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26. Optical, chemical, depth, and magnetic characterization of Mg/Co-based nanometric periodic multilayers
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Imène Esteve, Z. S. Wang, Jingtao Zhu, Christian Meny, S. Nannarone, Nicola Mahne, Adriano Verna, K. Le Guen, Philippe Jonnard, M.-H. Hu, H. Ch. Li, S.-K. Zhou, Michael Walls, Jean-Michel André, Anouk Galtayries, A. Giglia, AA. VV., Lequime M, Macleod H A, Ristau D, Jonnard, P., Le Guen, K., Hu, M. H., André, J. M., Zhou, S. K., Li, H. C. h., Zhu, J. T., Wang, Z. S., Mahne, N., Giglia, A., Nannarone, S., Verna, Adriano, Meny, C., Galtayries, A., Estève, I., and Walls, M.
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Secondary ion mass spectrometry ,X-ray reflectivity ,ultraviolet optical elements ,multilayer systems ,Magnetization ,Materials science ,Absorption edge ,Scanning electron microscope ,Magnetism ,Annealing (metallurgy) ,Analytical chemistry ,Emission spectrum - Abstract
We have developed and elaborated a series of Mg/Co-based periodic multilayers to build efficient mirrors for the extreme ultraviolet (EUV) range. For s-polarized light and at 45° of grazing incidence, the reflectivity of as-deposited Mg/Co is 42.6% at 25.1 nm. X-ray emission spectroscopy and nuclear magnetic resonance measurements do not indicate any noticeable interdiffusion at the interfaces between layers. Scanning transmission electronic microscopy images attest the high structural quality of the stack. X-ray reflectivity (XRR) curves in the hard x-ray and EUV domains confirm this description and estimate a weak interfacial roughness (~ 0.5 nm). Taking advantage of the magnetic character of Co, we have performed resonant magnetic reflectivity measurements by scanning the photon energy around the Co L absorption edge for opposite circular polarizations. The magnetization profile of the Co layers within Co/Mg determined with an expected depth resolution of one monolayer confirms the interface abruptness. Scanning electron microscopy images and XRR curves give evidence of the thermal stability of Mg/Co up to 300 °C. From that value, a strong change in the sample morphology due to the delamination of the multilayer from the substrate occurs. This should account for the drastic reflectivity drop observed above this temperature. Starting from Mg/Co, we have inserted a Zr layer at one or at the other interface or at both interfaces to estimate the effect of the introduction of a third material within the period. We have found that Mg/Co/Zr is more efficient (50% of reflectivity) than Mg/Zr/Co and Mg/Zr/Co/Zr (~ 40%). Through time-of-flight secondary ion mass spectrometry depth profiling and NMR measurements, we have assigned this difference to an intermixing process when Co layers are deposited onto Zr layers.
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- 2011
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27. A Bayesian Estimation of Reliability Measures of Stepwise Exponential Distribution System
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M. H. Hu
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Mathematical optimization ,Bayes estimator ,Mean time between failures ,Engineering ,Exponential distribution ,business.industry ,Mechanical Engineering ,Failure rate ,Computer Graphics and Computer-Aided Design ,Predictive maintenance ,Computer Science Applications ,Bayesian statistics ,Mechanics of Materials ,Statistics ,business ,Reliability (statistics) ,Mean time to repair - Abstract
This paper presents an analysis method for reliability measures of a system with step changes in failure and repair rates. Both failure and repair time have exponential function of time. Such a system is called a stepwise exponential distribution system. This kind of failure process can take place in various equipments. This paper deals with the system having components in series arrangement. Bayesian statistics is used in defining prior and posterior probability density functions of failure and repair rates. These functions provide information for the estimation of reliability measures: 1) failure and repair rates, 2) mean time to failure, 3) mean time to repair, 4) reliability function and 5) availability. A sample problem is given to illustrate the methodology. The Bayesian estimation of the stepwise exponential distribution model is useful in the planning of equipment predictive maintenance.
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28. Structural properties of Al/Mo/SiC multilayers with high reflectivity for extreme ultraviolet light
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Franck Delmotte, Evgueni Meltchakov, Philippe Jonnard, M.-H. Hu, Jean-Michel André, Karine Le Guen, Anouk Galtayries, Laboratoire de Chimie Physique - Matière et Rayonnement (LCPMR), Université Pierre et Marie Curie - Paris 6 (UPMC)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS), Laboratoire Charles Fabry de l'Institut d'Optique / Scop, Laboratoire Charles Fabry de l'Institut d'Optique (LCFIO), Université Paris-Sud - Paris 11 (UP11)-Institut d'Optique Graduate School (IOGS)-Centre National de la Recherche Scientifique (CNRS)-Université Paris-Sud - Paris 11 (UP11)-Institut d'Optique Graduate School (IOGS)-Centre National de la Recherche Scientifique (CNRS), Laboratoire de Physico-Chimie des Surfaces (LPCS), Ecole Nationale Supérieure de Chimie de Paris - Chimie ParisTech-PSL (ENSCP), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS), ANR-07-BLAN-0150,ATTOMIX,Design and characterization of XUV multilayer mirrors for attosecond pulses(2007), Centre National de la Recherche Scientifique (CNRS)-Institut d'Optique Graduate School (IOGS)-Université Paris-Sud - Paris 11 (UP11)-Centre National de la Recherche Scientifique (CNRS)-Institut d'Optique Graduate School (IOGS)-Université Paris-Sud - Paris 11 (UP11), Delmotte, Franck, and Blanc - Design and characterization of XUV multilayer mirrors for attosecond pulses - - ATTOMIX2007 - ANR-07-BLAN-0150 - BLANC - VALID
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[PHYS.PHYS.PHYS-OPTICS] Physics [physics]/Physics [physics]/Optics [physics.optics] ,Materials science ,Ultraviolet Rays ,Carbon Compounds, Inorganic ,Extreme ultraviolet lithography ,chemistry.chemical_element ,Synchrotron radiation ,02 engineering and technology ,01 natural sciences ,Photometry ,010309 optics ,Optics ,X-ray photoelectron spectroscopy ,Aluminium ,Materials Testing ,0103 physical sciences ,Thin film ,Lenses ,Molybdenum ,[PHYS.PHYS.PHYS-OPTICS]Physics [physics]/Physics [physics]/Optics [physics.optics] ,business.industry ,Silicon Compounds ,Membranes, Artificial ,Equipment Design ,021001 nanoscience & nanotechnology ,Atomic and Molecular Physics, and Optics ,Equipment Failure Analysis ,Secondary ion mass spectrometry ,Refractometry ,chemistry ,Extreme ultraviolet ,0210 nano-technology ,business ,Aluminum - Abstract
International audience; We present the results of an optical and chemical, depth and surface study of Al/Mo/SiC periodic multilayers, designed as high reflectivity coatings for the extreme ultra-violet (EUV) range. In comparison to the previously studied Al/SiC system, the introduction of Mo as a third material in the multilayer structure allows us to decrease In comparison to the previously studied Al/SiC system with a reflectance of 37% at near normal incidence around 17 nm, the introduction of Mo as a third material in the multilayer structure allows us to decrease the interfacial roughness and achieve an EUV reflectivity of 53.4%, measured with synchrotron radiation. This is the first report of a reflectivity higher than 50% around 17 nm. Time-of-flight secondary ion mass spectrometry (ToFSIMS) and x-ray photoelectron spectroscopy (XPS) measurements are performed on the Al/Mo/SiC system in order to analyze the individual layers within the stack. ToF-SIMS and XPS results give evidence that the first SiC layer is partially oxidized, but the O atoms do not reach the first Mo and Al layers. We use these results to properly describe the multilayer stack and discuss the possible reasons for the difference between the measured and simulated EUV reflectivity values.
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- 2010
29. Comparison of Mg-based multilayers for solar He II radiation at 30.4 nm wavelength
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Qiushi Huang, Karine Le Guen, Haochuan Li, S. M. Zhou, Jingtao Zhu, Philippe Jonnard, M.-H. Hu, Jean-Michel André, and Zhanshan Wang
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Materials science ,Silicon ,business.industry ,Materials Science (miscellaneous) ,Bremsstrahlung ,chemistry.chemical_element ,Synchrotron radiation ,Sputter deposition ,Industrial and Manufacturing Engineering ,Semimetal ,Wavelength ,Optics ,chemistry ,Sputtering ,Extreme ultraviolet ,Optoelectronics ,Business and International Management ,business - Abstract
Mg-based multilayers, including SiC/Mg, Co/Mg, B(4)C/Mg, and Si/Mg, are investigated for solar imaging and a He II calibration lamp at a 30.4 nm wavelength. These multilayers were fabricated by a magnetron sputtering method and characterized by x-ray reflection. The reflectivities of these multilayers were measured by synchrotron radiation. Near-normal-incidence reflectivities of Co/Mg and SiC/Mg multilayer mirrors are as high as 40.3% and 44.6%, respectively, while those of B(4)C/Mg and Si/Mg mirrors are too low for application. The measured results suggest that SiC/Mg, Co/Mg multilayers are promising for a 30.4 nm wavelength.
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- 2010
30. Development and Interfacial Characterization of Co/Mg Periodic Multilayers for the EUV Range
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Jean-Michel André, H. Ch. Li, Z.-S. Wang, S.-K. Zhou, K. Le Guen, Philippe Jonnard, Jingtao Zhu, M.-H. Hu, Christian Meny, Laboratoire de Chimie Physique - Matière et Rayonnement (LCPMR), Université Pierre et Marie Curie - Paris 6 (UPMC)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS), Institute of Precision Optical Engineering [Shangai] (IPOE), Tongji University, Institut de Physique et Chimie des Matériaux de Strasbourg (IPCMS), Université de Strasbourg (UNISTRA)-Matériaux et nanosciences d'Alsace (FMNGE), Institut de Chimie du CNRS (INC)-Université de Strasbourg (UNISTRA)-Université de Haute-Alsace (UHA) Mulhouse - Colmar (Université de Haute-Alsace (UHA))-Institut National de la Santé et de la Recherche Médicale (INSERM)-Centre National de la Recherche Scientifique (CNRS)-Institut de Chimie du CNRS (INC)-Université de Strasbourg (UNISTRA)-Université de Haute-Alsace (UHA) Mulhouse - Colmar (Université de Haute-Alsace (UHA))-Institut National de la Santé et de la Recherche Médicale (INSERM)-Centre National de la Recherche Scientifique (CNRS)-Centre National de la Recherche Scientifique (CNRS)-Réseau nanophotonique et optique, Centre National de la Recherche Scientifique (CNRS)-Université de Strasbourg (UNISTRA)-Université de Haute-Alsace (UHA) Mulhouse - Colmar (Université de Haute-Alsace (UHA))-Centre National de la Recherche Scientifique (CNRS)-Université de Strasbourg (UNISTRA), Université de Strasbourg (UNISTRA)-Centre National de la Recherche Scientifique (CNRS)-Matériaux et Nanosciences Grand-Est (MNGE), Université de Strasbourg (UNISTRA)-Université de Haute-Alsace (UHA) Mulhouse - Colmar (Université de Haute-Alsace (UHA))-Institut National de la Santé et de la Recherche Médicale (INSERM)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS)-Université de Strasbourg (UNISTRA)-Université de Haute-Alsace (UHA) Mulhouse - Colmar (Université de Haute-Alsace (UHA))-Institut National de la Santé et de la Recherche Médicale (INSERM)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS)-Réseau nanophotonique et optique, and Université de Strasbourg (UNISTRA)-Université de Haute-Alsace (UHA) Mulhouse - Colmar (Université de Haute-Alsace (UHA))-Centre National de la Recherche Scientifique (CNRS)-Université de Strasbourg (UNISTRA)-Centre National de la Recherche Scientifique (CNRS)
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Materials science ,Extreme ultraviolet lithography ,Mg ,Analytical chemistry ,02 engineering and technology ,Surface finish ,Boron carbide ,Photon energy ,01 natural sciences ,[SPI.MAT]Engineering Sciences [physics]/Materials ,Co ,chemistry.chemical_compound ,0103 physical sciences ,x-ray emission ,Emission spectrum ,Physical and Theoretical Chemistry ,010302 applied physics ,[PHYS.PHYS.PHYS-OPTICS]Physics [physics]/Physics [physics]/Optics [physics.optics] ,multilayer ,EUV reflectivity ,021001 nanoscience & nanotechnology ,NMR ,Surfaces, Coatings and Films ,Electronic, Optical and Magnetic Materials ,X-ray reflectivity ,Wavelength ,Chemical state ,Crystallography ,General Energy ,chemistry ,[PHYS.COND.CM-GEN]Physics [physics]/Condensed Matter [cond-mat]/Other [cond-mat.other] ,x-ray reflectivity ,interface ,0210 nano-technology - Abstract
Reprinted with permission from (J. Phys. Chem. C, 2010, 114 (14), pp 6484-6490). Copyright (2010) American Chemical Society.; International audience; We propose a new system, namely the periodic Co/Mg multilayer system, for optics applications in the EUV range. Close to the Mg L edge, i.e., around a wavelength of 25 nm or a photon energy of 50 eV, a reflectivity of about 43% is measured at 45° for s-polarized radiation. Moreover, it appears that this system is stable over a period of time of three months. The introduction of thin boron carbide interfacial layers proves disastrous contrary to simulations that show this could be beneficial. We combine X-ray reflectivity in the hard X-ray range, X-ray emission spectroscopy, and nuclear magnetic resonance to determine the thickness and roughness of the Co and Mg layers as well as the chemical state of the Co and Mg atoms at the interfaces. This reveals that in the Co/Mg system the interfaces are abrupt and there is no interdiffusion between the Co and Mg layers. Then the difference between the experimental and simulated reflectivities is ascribed to the interfacial roughness of the order of 0.4 nm. In the Co/Mg/B4C system, evidence of a large mixing of the Co and B4C layers is presented and explains the poor reflectance of this system.
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- 2010
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31. Introduction of Zr in Mg/Co nanometric periodic multilayers
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Philippe Jonnard, Karine Le Guen, Zhanshan Wang, S. M. Zhou, Jean-Michel André, M.-H. Hu, Jingtao Zhu, Christian Meny, Nicola Mahne, Stefano Nannarone, Haochuan Li, and Angelo Giglia
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Zirconium ,Materials science ,Magnetism ,multilayer ,Extreme ultraviolet lithography ,Analytical chemistry ,chemistry.chemical_element ,Reflectivity ,Chemical species ,Crystallography ,chemistry ,Extreme ultraviolet ,Local environment ,Reflectometry - Abstract
We study the introduction of Zr as a third material within a nanometric periodic Mg/Co structure designed to work as optical component in the EUV range. Mg/Co, Mg/Zr/Co, Mg/Co/Zr and Mg/Zr/Co/Zr multilayers are designed, then characterized in terms of structural quality and optical performances through X-ray and EUV reflectometry measurements respectively. For the Mg/Co/Zr structure, the reflectance value is reported to be 50% at 25.1 nm and 45° of grazing incidence. Nuclear Magnetic Resonance (NMR) measurements are performed to study the nearest neighbour local environment around the Co atoms.
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- 2010
32. Introduction of Zr in nanometric periodic Mg/Co multilayers
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Philippe Jonnard, Angela Giglia, Jean-Michel André, Jie Zhu, S.-K. Zhou, S. Nannarone, Z.-S. Wang, K. Le Guen, M.-H. Hu, N. Mahne, Haochuan Li, Laboratoire de Chimie Physique - Matière et Rayonnement (LCPMR), Université Pierre et Marie Curie - Paris 6 (UPMC)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS), Institute of Precision Optical Engineering [Shangai] (IPOE), Tongji University, CNR Istituto Officina dei Materiali (IOM), Consiglio Nazionale delle Ricerche [Roma] (CNR), and National Research Council of Italy | Consiglio Nazionale delle Ricerche (CNR)
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Materials science ,Annealing (metallurgy) ,Extreme ultraviolet lithography ,multilayers ,Mg ,Analytical chemistry ,chemistry.chemical_element ,FOS: Physical sciences ,02 engineering and technology ,01 natural sciences ,Spectral line ,010309 optics ,Co ,Transition metal ,0103 physical sciences ,General Materials Science ,material order ,x-ray and EUV reflectivity ,Alkaline earth metal ,Zirconium ,[PHYS.PHYS.PHYS-OPTICS]Physics [physics]/Physics [physics]/Optics [physics.optics] ,Condensed Matter - Materials Science ,Zr ,multilayer ,Materials Science (cond-mat.mtrl-sci) ,General Chemistry ,Atmospheric temperature range ,021001 nanoscience & nanotechnology ,Condensed Matter - Other Condensed Matter ,chemistry ,[PHYS.COND.CM-GEN]Physics [physics]/Condensed Matter [cond-mat]/Other [cond-mat.other] ,X-ray crystallography ,0210 nano-technology ,Physics - Optics ,Other Condensed Matter (cond-mat.other) ,Optics (physics.optics) - Abstract
We study the introduction of a third material, namely Zr, within a nanometric periodic Mg/Co structure designed to work as optical component in the extreme UV (EUV) spectral range. Mg/Co, Mg/Zr/Co, Mg/Co/Zr and Mg/Zr/Co/Zr multilayers are designed, then characterized in terms of structural quality and optical performances through X-ray and EUV reflectometry measurements respectively. For the Mg/Co/Zr structure, the reflectance value is equal to 50% at 25.1 nm and 45deg of grazing incidence and reaches 51.3% upon annealing at 200deg C. Measured EUV reflectivity values of tri-layered systems are discussed in terms of material order within a period and compared to the predictions of the theoretical model of Larruquert. Possible applications are pointed out., Comment: 19 pages
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- 2010
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33. Thermal properties, optical and interface characterization of Mg/Co multilayers for the EUV range
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H. Ch. Li, Jean-Michel André, Jingtao Zhu, Nicola Mahne, Z. S. Wang, Philippe Jonnard, M.-H. Hu, S.-K. Zhou, K. Le Guen, A. Giglia, and Stefano Nannarone
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interfaces ,X-ray reflectivity ,Chemical species ,Chemical state ,Materials science ,Scanning electron microscope ,Annealing (metallurgy) ,multilayers ,Extreme ultraviolet lithography ,Analytical chemistry ,Thermal stability ,Emission spectrum - Abstract
We present the results of the thermal stability of Mg/Co multilayers in the EUV range. The annealing study is performed up to a temperature of 400°C. The X-ray reflectivity at 0.154 nm is used in order to determine the structural parameters (thickness, roughness and density) of the layers. The measurements of the EUV reflectivity around 25 nm show that the reflectivity decreases when the annealing temperature increases above 300°C. X-ray emission spectroscopy is performed to determine the chemical state of the Mg atoms within the Mg/Co multilayer. The results show a small oxidation after annealing at 305°C, which increases greatly at 400°C. Scanning electron microscopy images of cross sections of the multilayer show a change of the surface morphology above 305°C. This large change of morphology and the oxidation explain the large reflectivity loss.
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- 2010
34. Co/Mg/X Multilayer Mirrors For the EUV Range
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Z. S. Wang, M.-H. Hu, J.-M. André, S.-K. Zhou, K. Le Guen, H. Ch. Li, P. Jonnard, and Jingtao Zhu
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Materials science ,business.industry ,Extreme ultraviolet lithography ,Superlattice ,Analytical chemistry ,chemistry.chemical_element ,Yttrium ,Polarization (waves) ,Electromagnetic radiation ,Carbide ,Barrier layer ,Optics ,chemistry ,Transition metal ,business - Abstract
A new material combination namely Co/Mg multilayer designed for optics applications in the EUV range, is reported. Simulations show that reflectivity value of the Co/Mg multilayer can reach a reflectivity of 55% at 25.2 nm (49.2 eV), when the grazing incidence angle is set to 45° and s polarization is considered. The introduction of additional materials, e.g., Y and Zr can improve the reflectivity to 61%. Co/Mg and Co/Mg/B4C multilayers have been deposited following the parameters deduced from the simulations. The introduction of a B4C barrier layer would in principle increase the multilayer reflectivity to 61%. In fact the reflectivity measurements at 0.154 nm show that the introduction of B4C does not improve the structural quality of the multilayers.
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- 2010
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35. Biochemical properties of recombinant mutants of nonglycosylated single chain urokinase-type plasminogen activator
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H.R. Lijnen, D. Collen, Xiaohua Li, M.-H Hu, and Lucien Nelles
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Glycosylation ,Plasmin ,medicine.medical_treatment ,Molecular Sequence Data ,Biophysics ,Biochemistry ,law.invention ,Structure-Activity Relationship ,Structural Biology ,In vivo ,law ,Cricetinae ,Fibrinolysis ,medicine ,Animals ,Fibrinolysin ,Molecular Biology ,Urokinase ,Base Sequence ,Chemistry ,Chinese hamster ovary cell ,Plasminogen ,Urokinase-Type Plasminogen Activator ,Molecular biology ,Recombinant Proteins ,In vitro ,Enzyme Activation ,Oligodeoxyribonucleotides ,Mutagenesis, Site-Directed ,Recombinant DNA ,Plasminogen activator ,medicine.drug - Abstract
The role of glycosylation on the enzymatic properties of single chain urokinase-type plasminogen activator (scu-PA) was investigated by site-specific mutagenesis of the glycosylated Asn-302 residu to Gln. In addition, the role of the NH2-terminal polypeptide chain and of the Cys-148 to Cys-279 interchain disulphide bond on the activity of non-glycosylated scu-PA was investigated. Therefore, variants of recombinant scu-PA (rscu-PA) were produced by transfecting Chinese hamster ovary cells with cDNA encoding rscu-PA N302Q (rscu-PA with Asn-302 to Gln mutation), rscu-PA C279A,N302Q (rscu-PA with Cys-279 to Ala and Asn-302 to Gln mutations) or rscu-PA del(N2-F157)C279A,N302Q (rscu-PA C279A,N302Q with deletion of Asn-2 through Phe-157). These mutants were purified to homogeneity from conditioned cell culture medium and were obtained essentially as single chain molecules with specific activities on fibrin plates of (mean +/- S.E.; n = 6) 45,000 +/- 5000. IU/mg, 19,000 +/- 800 IU/mg and < or = 100 IU/mg for rscu-PA N302Q, rscu-PA C279A,N302Q and rscu-PA del(N2-F157)C279A,N302Q, respectively, as compared to 64,000 +/- 2600 IU/mg for wild-type rscu-PA obtained in the same expression system. Plasmin quantitatively converts rscu-PA N302Q and rscu-PA C279A,N302Q to amidolytically active two-chain derivatives with a specific activity of 56,000 IU/mg and 32,000 IU/mg, respectively, as compared to 75,000 IU/mg for wild-type rscu-PA. Plasminogen activation as a function of time was comparable for rscu-PA N302Q and wild-type rscu-PA, and somewhat slower for rscu-PA C279A,N302Q. In a human plasma milieu in vitro, consisting of a 125I-fibrin labeled plasma clot submerged in plasma, 50 percent clot lysis in 2 h required 2.2 micrograms/ml rscu-PA N302Q and 6.0 micrograms/ml rscu-PA C279A,N302Q, as compared to 3.2 micrograms/ml wild-type rscu-PA. In contrast, rscu-PA del(N2-F157)C279A,N302Q was not converted to an amidolytically active two chain derivative by plasmin, and did not induce significant plasminogen activation in purified systems or clot lysis in a human plasma milieu. Following bolus injections in hamsters, the initial half-lives (1.8-2.6 min) and the plasma clearances (0.6-1.5 ml min-1) were comparable for wild-type rscu-PA and for the three rscu-PA mutants. These results suggest that the fibrinolytic activity in a plasma milieu in vitro and the in vivo turnover of rscu-PA are not markedly affected by the absence of carbohydrate.(ABSTRACT TRUNCATED AT 400 WORDS)
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- 1992
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36. Flywheel energy storage system for voltage sag compensation
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G. W. Jhang, Wen-Ren Yang, Chau-Shing Wang, Z. Y. He, Chung-Ping Young, Liang-Rui Chen, T. Y. Guo, K. Y. Huang, and M. H. Hu
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Discrete wavelet transform ,Engineering ,Chipset ,business.industry ,Electrical engineering ,Monitoring system ,Hardware_PERFORMANCEANDRELIABILITY ,Transient analysis ,Flywheel ,Compensation (engineering) ,Flywheel energy storage system ,Voltage sag ,Electronic engineering ,business - Abstract
This paper presents a real-time voltage sag monitoring system. Discrete wavelet transform (DWT) is implemented by using an embedded chipset in order to monitor initial and ending points of voltage sag. A flywheel energy storage system (FESS) is designed for voltage sag compensation, and proof-of-principle experiment is presented.
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- 2009
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37. Optical, chemical, and depth characterization of Al/SiC periodic multilayers
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M.-H. Hu, Anouk Galtayries, Evgueni Meltchakov, Jean-Michel André, Philippe Jonnard, K. Le Guen, Christophe Hecquet, Franck Delmotte, Laboratoire de Chimie Physique - Matière et Rayonnement (LCPMR), Université Pierre et Marie Curie - Paris 6 (UPMC)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS), Laboratoire Charles Fabry de l'Institut d'Optique / Scop, Laboratoire Charles Fabry de l'Institut d'Optique (LCFIO), Centre National de la Recherche Scientifique (CNRS)-Institut d'Optique Graduate School (IOGS)-Université Paris-Sud - Paris 11 (UP11)-Centre National de la Recherche Scientifique (CNRS)-Institut d'Optique Graduate School (IOGS)-Université Paris-Sud - Paris 11 (UP11), Laboratoire de Physico-Chimie des Surfaces (LPCS), Ecole Nationale Supérieure de Chimie de Paris - Chimie ParisTech-PSL (ENSCP), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS), Laboratoire de Chimie Physique - Matière et Rayonnement ( LCPMR ), Université Pierre et Marie Curie - Paris 6 ( UPMC ) -Centre National de la Recherche Scientifique ( CNRS ), Laboratoire Charles Fabry de l'Institut d'Optique ( LCFIO ), Université Paris-Sud - Paris 11 ( UP11 ) -Institut d'Optique Graduate School ( IOGS ) -Centre National de la Recherche Scientifique ( CNRS ) -Université Paris-Sud - Paris 11 ( UP11 ) -Institut d'Optique Graduate School ( IOGS ) -Centre National de la Recherche Scientifique ( CNRS ), Laboratoire de Physico-Chimie des Surfaces ( LPCS ), Ecole Nationale Supérieure de Chimie de Paris- Chimie ParisTech-PSL ( ENSCP ) -Centre National de la Recherche Scientifique ( CNRS ), and Université Paris-Sud - Paris 11 (UP11)-Institut d'Optique Graduate School (IOGS)-Centre National de la Recherche Scientifique (CNRS)-Université Paris-Sud - Paris 11 (UP11)-Institut d'Optique Graduate School (IOGS)-Centre National de la Recherche Scientifique (CNRS)
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[PHYS.PHYS.PHYS-OPTICS]Physics [physics]/Physics [physics]/Optics [physics.optics] ,[ PHYS.PHYS.PHYS-OPTICS ] Physics [physics]/Physics [physics]/Optics [physics.optics] ,Chemistry ,Refractory metals ,Analytical chemistry ,02 engineering and technology ,Surface finish ,021001 nanoscience & nanotechnology ,01 natural sciences ,010309 optics ,X-ray reflectivity ,Secondary ion mass spectrometry ,Chemical species ,Chemical state ,Time of flight ,0103 physical sciences ,Emission spectrum ,0210 nano-technology ,ComputingMilieux_MISCELLANEOUS - Abstract
We present the characterization of Al/SiC periodic multilayers designed for op tical applications. In some samples, a thin layer of W or Mo is added at the SiC-on-Al interfaces. We use x-ray reflectivity (XRR) in order to determine the parameters of the stacks, i.e. thickness and roughness of all the layers. We have performed x-ray emission spectroscopy (XES) to identify the chemical state of th e Al and Si atoms present within the stru cture from an analysis of the shape of the Al KE and Si KE emission bands. Finally, time of flight secondary ion mass spectrometry (ToF-SIMS) is used to obtain the depth profile of the different elements present within the studied stacks. A fit of the XRR curves shows that the Al/SiC multilayer present large interfacial roughness (up to 2.8 nm), which is decreased considerably (down to 1 nm or less) when the refractory metal layers are introduced in the periodic structure. The combination of XES and ToF-SIMS allows us to conclude that in these systems the roughness is a purely geometrical parameter and not related to chemical interfacial reactions. Keywords: periodic multilayer, x-ray emission, x-ray reflectivity, time of flight secondary ion mass spectrometry * philippe.jonnard@upmc.fr , phone 33 1 44 27 63 03, fax 33 1 44 27 62 26, www.lcpmr.upmc.fr/
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- 2009
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38. Parallelization of a 2D fluid modeling code for non-thermal gas discharges
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Jong-Shinn Wu, Chin-Te Hung, Y.-M. Chiu, Feng Nan Hwang, and M.-H. Hu
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Physics ,Independent equation ,Finite difference method ,Mechanics ,Plasma modeling ,Euler equations ,Physics::Fluid Dynamics ,Nonlinear system ,symbols.namesake ,Classical mechanics ,Continuity equation ,symbols ,Poisson's equation ,Navier–Stokes equations - Abstract
Summary form only given. Progress in developing a parallelized 2D/2D-axisymmetric fluid and neutral flow modeling code (PFNF) for non-thermal plasma simulations is reported in this paper. Major modules of this PFNF include: 1) a fluid modeling code for gas discharge with power ranging from 10 kH-100 MHz, 2) a Navier- Stokes equation solver for neutral flow, and 3) a coupled external circuit analysis code. The fluid modeling code solves charged species continuity equations using drift-diffusion approximation for the particle flux term, electron energy density equation, Poisson's equation, and Maxwell equation. The Navier-Stokes equation solver solves the continuity equation, momentum equations and energy equation for the mass-averaged neutral flow, which is capable of modeling conjugate heat transfer for solid and gas. The external circuit analysis code applies Kirchoff's current law by considering the external RLC and plasma together at the same time. All model equations are nondimensionalized and discretized using fully implicit finite-difference method with Scharfetter- Gummel scheme for the fluxes in the fluid modeling equations and exponential scheme for the fluxes in the Navier-Stokes equations. Both backward Euler and higher-order temporal schemes are included. All transport coefficients of charged species and rate constants of chemical reactions can be expressed as the nonlinear function of electron temperature or gas temperature. The resulting discretized nonlinear coupled equations are then solved by the parallel Newton-Krylov-Schwarz (NKS) algortihm, in which the overlapping additive Schwarz method (ASM) and bi-CGSTAB scheme is used as the preconditioner and linear matrix equation solver, respectively. Parallel performance is tested on a PC cluster system (IBM-13 50 at NCHC of Taiwan) up to 128 processors. Several test cases, including quasi-1D, quasi-1D-radial, and 2D-axisymmetric parallel plate under various operating conditions will be presented in the presentation.
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- 2008
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39. RETROSPECTIVE STUDY OF MITOCHONDRIAL DISORDER IN CHILDHOOD
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H. S. Wang, K. L. Lin, D. C. Yan, L. S. Ro, C. Y. Wang, M. H. Hu, M. L. Chou, and P. C. Hung
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Pediatrics ,medicine.medical_specialty ,business.industry ,Pediatrics, Perinatology and Child Health ,Medicine ,Retrospective cohort study ,Neurology (clinical) ,General Medicine ,business - Published
- 2006
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40. A temporal multi-scale algorithm for efficient fluid modeling of a one-dimensional gas discharge
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K. M. Lin, C. T. Hung, Y. S. Chen, Jong-Shinn Wu, B. R. Gu, and M. H. Hu
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Reduction (complexity) ,Chemistry ,Impurity ,chemistry.chemical_element ,Dielectric barrier discharge ,Condensed Matter Physics ,Algorithm ,Nitrogen ,Water vapor ,Helium ,Electric discharge in gases ,Power (physics) - Abstract
In this study, we present a temporal multi-scale algorithm (TMA) for efficient fluid modeling of a one-dimensional gas discharge with complex plasma chemistry. A helium dielectric barrier discharge driven by a power source with a frequency of 25 kHz is used as an example to demonstrate the superior capability of the TMA in accelerating fluid modeling simulations, while maintaining the same accuracy as compared to lengthy benchmarking fluid modeling using a single time-scale approach. The plasma chemistry considers 36 species and 121 reaction channels, which include some impurities such as nitrogen (25 ppm), oxygen (10 ppm) and water vapor (1 ppm), in addition to the helium itself. The results show that the runtime using the TMA can be dramatically reduced to 4% (25 times faster) with a relative difference of spatially averaged number densities generally less than 1% for all species between the TMA and the benchmarking cases when five initial cycles, five supplementary cycles and four repeated stages are used. Further reduction of the accuracy requirements to 44% for some specific species can lead to 92 times faster performance with the use of two initial cycles, two supplementary cycles and two repeated stages. The outlook for multi-dimensional fluid modeling considering a gas flow field is also described at the end of the paper.
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- 2014
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41. [The study of P68 RNA helicase on cell transformation]
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Y, Wei and M H, Hu
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DEAD-box RNA Helicases ,Mice ,Mice, Inbred BALB C ,Cell Transformation, Neoplastic ,Animals ,Humans ,Mice, Nude ,3T3 Cells ,Neoplasms, Experimental ,Transfection ,Protein Kinases ,RNA Helicases - Abstract
The P68 nuclear protein is an ATP-dependent RNA helicase and RNA-dependent ATPase, and has been proved to have functions in the regulation of cell growth and division. Different phenotypes of P68 between tumouric cell lines (HeLa, TC3H10) and non-tumouric cell lines (NIH3T3 and NC3H10) were observed, and we reasoned that overexpression of P68 might profoundly affect cellular growth properties. We report here that overexpression human P68 by transfection of recombinant P68 expression vector in NIH3T3 and NC3H10 fibroblasts causes their tumorigenic transformation as determined by four criteria: (1) the morphology of transfectants from long fibric to spindle shaped; (2) formation of transformed foci on the monolayer of cells; (3) the transfectants acquired the ability to grow on soft agar forming cell microsphere cube; (4) tumor formation in nude mice after injection of transfected cells for 3-4 weeks.
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- 2001
42. Validity of force platform measures for stance stability under varying sensory conditions
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M H, Hu, Y C, Hung, Y L, Huang, C D, Peng, and S S, Shen
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Adult ,Male ,Posture ,Visual Perception ,Humans ,Neurophysiology ,Spatial Behavior ,Postural Balance ,Psychomotor Performance - Abstract
Maintaining stance stability under varying sensory environment is an essential function in the elderly and among patients. Testing sensory organization ability of standing balance, the Sensory Organization Test (SOT), has become a standard procedure in many clinical and laboratory settings. The stance stability can be quantified by two forceplate measures in the SOT: the equilibrium score (ES) and the sway area (SA). This study compares the validity of the ES and the SA in detecting gender, trial, and sensory effects on stability in twenty (ten male, ten female) healthy young adults. Subjects were tested under six sensory conditions: eyes open (EO), eyes closed (EC), sway-referenced vision (Vs), sway-referenced support surface (Ss), eyes closed sway-referenced support surface (ECSs), and sway-referenced visual surround and support surface (VsSs). A visual surround and/or the support surface were tilted proportionately to the subject's spontaneous sway in the sway-referenced conditions. Three trials, 20-second for each trial, were repeated for each sensory condition. Above results demonstrated that the Pearson correlation coefficients between the ES and the SA were all highly significant (p.0001) except for the first trial of the EO condition. The consistencies in which the two measures discriminated among sensory conditions were tested by the Kendall's coefficient of concordance. The Kendall's coefficient for the ES (W = .843) and the SA (W = .866) were high and similar. Separate ANOVA procedure for the ES and SA revealed that both measures satisfactorily detected a significant sensory condition and trial effects and insignificant gender effect. We can conclude that ES and SA are valid measures of stance stability during the SOT. Our results confirm that healthy young adults have a poorer postural stability when the visual and somatosensory inputs are simultaneously altered. Moreover, the learning effect is observed during repeated trials within test conditions.
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- 1996
43. Management for patients with advanced T4 epidermoid carcinoma of the esophagus
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L S, Wang, K H, Chi, M H, Hu, H J, Fahn, and M H, Huang
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Male ,Esophageal Neoplasms ,Leucovorin ,Middle Aged ,Combined Modality Therapy ,Esophagectomy ,Survival Rate ,Chemotherapy, Adjuvant ,Antineoplastic Combined Chemotherapy Protocols ,Carcinoma, Squamous Cell ,Humans ,Female ,Radiotherapy, Adjuvant ,Fluorouracil ,Cisplatin ,Aged ,Follow-Up Studies ,Neoplasm Staging - Abstract
Available data concerning the treatment of patients with advanced T4 esophageal carcinoma are limited. A consecutive series of 42 patients with advanced T4M0 epidermoid carcinoma of the esophagus were studied from June 1987 to July 1992. The aim of this study was to evaluate the efficacy of various therapeutic modalities, and further evaluate the therapeutic options. The various therapeutic modalities included the following: Group I, feeding jejunostomy or endoesophageal intubation, 6 patients; Group II, palliative subtotal esophagectomy only, 8 patients; Group III, bypass procedures without tumor resection, 9 patients; Group IV, nutritional support and then treatment with irradiation (n=8) or concurrent radio-chemotherapy (n=4), 12 patients; Group V, subtotal esophagectomy, followed by aggressive concurrent radiochemotherapy, 7 patients. The total prescribed irradiation dose was 60 Gy (10 Gy/5 fractions/week). A combination regimen of chemotherapy consisted of cisplatin, 5-fluorouracil, and leucovorin (PFL regimen). For the patients undergoing esophagectomy or bypass procedures (n=24), the rates of operative complication and mortality were 45.8% and 25%, respectively. Side effects of adjuvant therapy (n=24) consisted of main airway irritation (100%), mucositis or gastrointestinal symptoms (83.3%), hematologic toxicity (79.2%), esophagitis or gastric ulcer (62.5%), alopecia (37.5%), and pneumonia (20.8%). The mortality due to toxicity of adjuvant therapy was 21.1% (4/19 patients). The mean survival times for each of the different groups was 1.9+/-0.5 months for Group I, 4.8+/-1.6 months for Group II, 5.2+/-1.2 months for Group III, 7.3+/-2.0 months for Group IV, and 20.3+/-2.5 months for Group V, respectively. Compared with patients of Groups I--IV, the Group V patients had a significantly superior one-year survival rate (P0.01). Our results demonstrated that esophagectomy followed by concurrent irradiation and PFL combination chemotherapy may provide a significant improvement in the quality of life and survival for appropriate patients with advanced T4M0 epidermoid carcinoma of the esophagus. Furthermore, more than one cycle of PFL regimen chemotherapy may result in a better prognosis. During the performance of such an aggressive treatment, the utmost care must be taken with the patient's nutrition and to prevent pulmonary complications.
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- 1996
44. Double-C-peptide human proinsulin
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G, Wei, M H, Hu, and J G, Tang
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Base Sequence ,C-Peptide ,Molecular Sequence Data ,Escherichia coli ,Humans ,Insulin ,Amino Acid Sequence ,Gene Expression Regulation, Bacterial ,Cloning, Molecular ,Recombinant Proteins ,Sulfur ,Proinsulin ,Protein Binding - Abstract
A fusion gene encoding double-C-peptide human proinsulin was constructed by insertion of a DNA fragment encoding human C-peptide into the 5'-terminal C-peptide coding sequence of a synthetic human proinsulin gene with correct reading frame and over-expressed in E. coli. The purified double-C-peptide human proinsulin shows decreased activity in receptor binding and insulin immune assays as compared with human proinsulin. Disulphide bond reconstitution studies demonstrate that there is not much more influence of the protein concentration on the yield of refolded double-C-peptide human proinsulin. The double-C-peptide human proinsulin shows a 1.86-fold human C-peptide immune activity as compared with that of human proinsulin and gives a good yield of the molecule with correct disulphide bonds in reconstitution studies strongly suggesting the existence of very flexible conformation of the C-peptide.
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- 1995
45. Thermal stability of Mg/Co multilayer with B_4C, Mo or Zr diffusion barrier layers
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Karine Le Guen, Zhanshan Wang, Jean-Michel André, M.-H. Hu, Philippe Jonnard, Hongjun Zhou, Haochuan Li, Jingtao Zhu, Tonglin Huo, and S. M. Zhou
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Barrier layer ,Materials science ,Optics ,Diffusion barrier ,business.industry ,Diffusion ,Extreme ultraviolet lithography ,Extreme ultraviolet ,Degradation (geology) ,Thermal stability ,Surface finish ,business ,Atomic and Molecular Physics, and Optics - Abstract
The efficiency of B(4)C, Mo and Zr barrier layers to improve thermal stability of Mg/Co multilayer up to 400 °C is investigated. Multilayers were deposited by direct current magnetron sputtering and characterized using X-ray and extreme ultraviolet reflection. The results suggest that B(4)C barrier layer is not effective due to drastic diffusion at Mg-B(4)C interface. Although introducing Mo barriers improves the thermal stability from 200 to 300 °C, it increases the interface roughness and thus degrades the optical performances. On the contrary, Zr barriers can significantly increase the thermal stability of Mg/Co up to 400 °C without optical performance degradation. Thus, Mg/Zr/Co/Zr is suitable for EUV applications requiring both optimal optical performances and heat resistance.
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- 2011
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46. Observation of an asymmetrical effect when introducing Zr in Mg/Co multilayers
- Author
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S.-K. Zhou, Christian Meny, M.-H. Hu, Jean-Michel André, H. Ch. Li, Philippe Jonnard, K. Le Guen, Jingtao Zhu, Anouk Galtayries, Z. S. Wang, Laboratoire de Chimie Physique - Matière et Rayonnement ( LCPMR ), Université Pierre et Marie Curie - Paris 6 ( UPMC ) -Centre National de la Recherche Scientifique ( CNRS ), Institute of Precision Optical Engineering ( IPOE ), Institut de Physique et Chimie des Matériaux de Strasbourg ( IPCMS ), Université de Strasbourg ( UNISTRA ) -Centre National de la Recherche Scientifique ( CNRS ) -Matériaux et nanosciences d'Alsace, Université de Strasbourg ( UNISTRA ) -Université de Haute-Alsace (UHA) Mulhouse - Colmar ( Université de Haute-Alsace (UHA) ) -Institut National de la Santé et de la Recherche Médicale ( INSERM ) -Centre National de la Recherche Scientifique ( CNRS ) -Université de Strasbourg ( UNISTRA ) -Université de Haute-Alsace (UHA) Mulhouse - Colmar ( Université de Haute-Alsace (UHA) ) -Institut National de la Santé et de la Recherche Médicale ( INSERM ) -Centre National de la Recherche Scientifique ( CNRS ) -Réseau nanophotonique et optique, Université de Strasbourg ( UNISTRA ) -Université de Haute-Alsace (UHA) Mulhouse - Colmar ( Université de Haute-Alsace (UHA) ) -Centre National de la Recherche Scientifique ( CNRS ) -Université de Strasbourg ( UNISTRA ), Laboratoire de Physico-Chimie des Surfaces ( LPCS ), Centre National de la Recherche Scientifique ( CNRS ), Laboratoire de Chimie Physique - Matière et Rayonnement (LCPMR), Université Pierre et Marie Curie - Paris 6 (UPMC)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS), Institute of Precision Optical Engineering [Shangai] (IPOE), Tongji University, Institut de Physique et Chimie des Matériaux de Strasbourg (IPCMS), Université de Strasbourg (UNISTRA)-Centre National de la Recherche Scientifique (CNRS)-Matériaux et nanosciences d'Alsace (FMNGE), Institut de Chimie du CNRS (INC)-Université de Strasbourg (UNISTRA)-Université de Haute-Alsace (UHA) Mulhouse - Colmar (Université de Haute-Alsace (UHA))-Institut National de la Santé et de la Recherche Médicale (INSERM)-Centre National de la Recherche Scientifique (CNRS)-Institut de Chimie du CNRS (INC)-Université de Strasbourg (UNISTRA)-Université de Haute-Alsace (UHA) Mulhouse - Colmar (Université de Haute-Alsace (UHA))-Institut National de la Santé et de la Recherche Médicale (INSERM)-Centre National de la Recherche Scientifique (CNRS)-Réseau nanophotonique et optique, Centre National de la Recherche Scientifique (CNRS)-Université de Strasbourg (UNISTRA)-Université de Haute-Alsace (UHA) Mulhouse - Colmar (Université de Haute-Alsace (UHA))-Centre National de la Recherche Scientifique (CNRS)-Université de Strasbourg (UNISTRA), Laboratoire de Physico-Chimie des Surfaces (LPCS), Ecole Nationale Supérieure de Chimie de Paris - Chimie ParisTech-PSL (ENSCP), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS), Université de Strasbourg (UNISTRA)-Centre National de la Recherche Scientifique (CNRS)-Matériaux et Nanosciences Grand-Est (MNGE), Université de Strasbourg (UNISTRA)-Université de Haute-Alsace (UHA) Mulhouse - Colmar (Université de Haute-Alsace (UHA))-Institut National de la Santé et de la Recherche Médicale (INSERM)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS)-Université de Strasbourg (UNISTRA)-Université de Haute-Alsace (UHA) Mulhouse - Colmar (Université de Haute-Alsace (UHA))-Institut National de la Santé et de la Recherche Médicale (INSERM)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS)-Réseau nanophotonique et optique, and Université de Strasbourg (UNISTRA)-Université de Haute-Alsace (UHA) Mulhouse - Colmar (Université de Haute-Alsace (UHA))-Centre National de la Recherche Scientifique (CNRS)-Université de Strasbourg (UNISTRA)-Centre National de la Recherche Scientifique (CNRS)
- Subjects
Materials science ,Physics and Astronomy (miscellaneous) ,Period (periodic table) ,Optical contrast ,Superlattice ,Aucun ,Analytical chemistry ,chemistry.chemical_element ,02 engineering and technology ,01 natural sciences ,010309 optics ,0103 physical sciences ,Zirconium ,multilayer ,Magnesium ,[CHIM.MATE]Chemical Sciences/Material chemistry ,[ PHYS.COND.CM-GEN ] Physics [physics]/Condensed Matter [cond-mat]/Other [cond-mat.other] ,021001 nanoscience & nanotechnology ,Reflectivity ,Secondary ion mass spectrometry ,Crystallography ,chemistry ,[PHYS.COND.CM-GEN]Physics [physics]/Condensed Matter [cond-mat]/Other [cond-mat.other] ,[ CHIM.MATE ] Chemical Sciences/Material chemistry ,interface ,0210 nano-technology ,Cobalt - Abstract
We have developed Mg/Co, Mg/Zr/Co, Mg/Co/Zr, and Mg/Zr/Co/Zr periodic multilayers and measured at 25.1 nm a reflectivity (R) highly sensitive to the material order within the period. To understand why Mg/Co/Zr is a more efficient mirror (R=50%) than Mg/Zr/Co and Mg/Zr/Co/Zr (similar to 40%), we have probed the interface quality through time-of-flight secondary ion mass spectrometry and nuclear magnetic resonance measurements. The Zr-on-Co interface is found quite sharp while a strong intermixing process is evidenced between the upper Co and lower Zr layers, responsible for the decrease in optical contrast and subsequent R loss. (C) 2011 American Institute of Physics. [doi:10.1063/1.3601859]
- Published
- 2011
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47. Vacuole sign and nodule sign in early peripheral bronchogenic carcinoma. Diagnostic value and pathologic correlation
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X M, Yang, M H, Hu, Y C, Xie, H Z, Yan, H R, Liu, D T, Wang, and P, Stark
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Diagnosis, Differential ,Carcinoma, Bronchogenic ,Lung Neoplasms ,Carcinoma, Squamous Cell ,Humans ,Tuberculoma ,Adenocarcinoma ,Lung ,Tuberculosis, Pulmonary - Abstract
We analyzed the radiological and pathological characteristics of 30 peripheral lung masses 1.5-3 cm in diameter. We describe the vacuole and the nodule sign. Retrospective examination of 100 conventional tomograms of peripheral pulmonary masses and comparison with the histological diagnoses allowed us to determine the usefulness of these two signs in differentiating small peripheral bronchogenic carcinomas from tuberculomas.
- Published
- 1990
48. 17.4 Kinetic analysis of lateral-wedge insole on symmetryof stance and ambulation in stroke individuals
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M.-H. Hu, C.H. Chen, Kwan-Hwa Lin, H.-M. Chai, Tung-Wu Lu, and Pei-Fang Tang
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medicine.medical_specialty ,Stroke patient ,business.industry ,Rehabilitation ,Vertical ground reaction force ,Kinetic analysis ,Biophysics ,medicine.disease ,medicine.disease_cause ,Gait ,Weight-bearing ,Physical medicine and rehabilitation ,Lateral wedge ,medicine ,Orthopedics and Sports Medicine ,business ,Stroke ,Symmetry index - Abstract
"Abstracts of the XVIIth Conference on Postural and Gait Research. Marseille, May 29th-June 2nd, 2005. KINETIC ANALYSIS OF LATERAL-WEDGE INSOLE ON SYMMETRY OF STANCE AND AMBULATION IN STROKE INDIVIDUALS Chien-Hsun Chen, Kwan-Hwa Lin, Tung-Wu Lu, Huei-Ming Chai, Pei-Fang Tang, Ming-Hsia Hu School and Graduate Institute of Physical Therapy, National Taiwan University Institute of Biomedical Engineering, National Taiwan University Introduction The stroke patients often have problems with asymmetry of stance and ambulation. This study was to assess the symmetry of weight bearing in stroke patients during stance and ambulation with and without wearing a lateral-wedge insole on the non-paretic side. Methods There were sixteen hemiplegic patients (mean age: 54.12±2.85 year old) with mean duration of illness 90.69 ± 21.77 days. The subject with and without 5∘lateral-wedge insole performed quiet standing on platforms (AMTI, USA) for 10 seconds, then walked with comfortable speed along a 6-m woody walkway. Symmetry index (SI) indicated the difference between the paretic and non-paretic limbs with zero being symmetric. Results The SI of vertical ground reaction force (GRF) during static standing was significantly improved (from 60.82% to 48.02%, p
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- 2005
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49. Isolation and characterization of plasminogen activator inhibitor 1 (PAI- 1)mutant( e350g, e351k)
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M.-H. Hu and G.-C. Sui
- Subjects
chemistry.chemical_compound ,Chemistry ,Plasminogen activator inhibitor-1 ,Mutant ,Hematology ,Isolation (microbiology) ,Molecular biology - Published
- 1994
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50. Optimization of Finned Tubes for Heat Transfer in Laminar Flow
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Y. P. Chang and M. H. Hu
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Dynamic scraped surface heat exchanger ,Materials science ,Mechanical Engineering ,Thermodynamics ,Laminar flow ,Heat transfer coefficient ,Mechanics ,Condensed Matter Physics ,Concentric tube heat exchanger ,Nusselt number ,Mechanics of Materials ,Heat generation ,Heat transfer ,Heat exchanger ,General Materials Science - Abstract
The heat transfer of fully developed laminar flow in internally finned tubes is investigated analytically. If there is no heat generation in the fluid, the highest Nusselt number is obtained for the tube with 22 fins extended to about 80 percent of the tube radius. Its value is almost 20 times that for the finless tube. When there is heat generation at sufficiently large rate, the number of fins is reduced from 22 to 16 in order to obtain the highest Nusselt number.
- Published
- 1973
- Full Text
- View/download PDF
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