31 results on '"X. H. Ji"'
Search Results
2. Level changes of serum high-sensitivity C-reactive protein and vascular endothelial growth factor in patients with St-segment elevation myocardial infarction after percutaneous coronary intervention
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H G, Wang, X H, Ji, C C, Wang, and X L, Tian
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Vascular Endothelial Growth Factor A ,C-Reactive Protein ,Percutaneous Coronary Intervention ,Treatment Outcome ,Risk Factors ,Humans ,ST Elevation Myocardial Infarction - Published
- 2021
3. [Effects of double-catheter epidural analgesia by lidocaine injection respectively on the delivery outcomes and maternal-infant complications for persistent posterior or lateral occipital position of protracted active phase]
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J Z, Li, L, Wang, X Z, Li, W G, Yu, L P, Kang, Y Q, Liu, X H, Ji, X F, Wu, M S, Wang, and H, Tao
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Adult ,Anesthesia, Epidural ,Labor, Obstetric ,Cesarean Section ,Infant, Newborn ,Pregnancy Outcome ,Lidocaine ,Pain ,Delivery, Obstetric ,Analgesia, Epidural ,Treatment Outcome ,Pregnancy ,Analgesia, Obstetrical ,Humans ,Female - Published
- 2020
4. Effect of laser energy on the crystal structure and UV response characteristics of mixed-phase MgZnO thin films deposited by PLD and the fabrication of high signal/noise ratio solar-blind UV detector based on mix-phase MgZnO at lower voltage
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X. H. Ji, Wenjun Liu, P. J. Cao, Q. L. An, Fang Jia, Y. M. Lu, Deyong Zhu, Y. X. Zeng, Shun Han, and X. K. Liu
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010302 applied physics ,Fused quartz ,Fabrication ,Materials science ,business.industry ,Biasing ,02 engineering and technology ,General Chemistry ,021001 nanoscience & nanotechnology ,Laser ,01 natural sciences ,law.invention ,Responsivity ,law ,0103 physical sciences ,Materials Chemistry ,Optoelectronics ,Thin film ,0210 nano-technology ,business ,Deposition (law) ,Dark current - Abstract
MgZnO thin films (with Mg0.4Zn0.6O as the target) were fabricated on fused quartz substrates employing PLD method under different laser energy densities. Cubic structured MgZnO thin films were made at laser energy densities of 20 J cm−2 and 22 J cm−2, whilst the MgZnO thin films were deposited along both cubic and hexagonal structures under higher laser energy density condition. When a higher energy density laser was focused on the MgZnO target during the deposition process, the MgZnO thin film was found to be deposited with a more hexagonal structure and a higher Zn composition. There are two response peaks located in the solar-blind UV and visible-blind UV regions within the UV response spectrum of the mixed-phase MgZnO based detector deposited at laser energy over 24 J cm−2. When the deposition laser energy density increased from 24 to 30 J cm−2, the maximum UV responsivity of the mixed-phase MgZnO-based detector increased from 0.06 A W−1 to 1 A W−1 at 40 V bias voltage, and the visible-blind UV response peak of the mix-phase MgZnO based detector was also higher due to the MgZnO adopting a more hexagonal structure; furthermore, a higher internal gain is obtained, which can be attributed to a higher density of interfaces between the MgZnO grains of different structures in the mixed-phase MgZnO thin film. At 5 V bias voltage, the Ilight(230 nm)/Idark ratio of the UV detector based on mix-phase MgZnO deposited at 24 J cm−2 reached 500, and the Ilight(290 nm)/Idark ratio of the UV detector based on mix-phase MgZnO deposited at 26 J cm−2 reached 1100. Therefore, the UV-detector based on mixed-phase MgZnO thin films is sensitive to solar-blind and visible-blind UV light with strong background noise (on Earth) when the boundaries between (111) an (200) cubic MgZnO makes obvious function in decreasing the dark current of the detectors at lower bias voltage.
- Published
- 2017
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5. Interfacial characteristics of electron beam welding joints of SiCp/Al composites
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N. N. Dong, S. G. Wang, X. Q. Zhao, and X. H. Ji
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Heat-affected zone ,Materials science ,Mechanical Engineering ,Metallurgy ,Weldability ,Welding ,Condensed Matter Physics ,Electric resistance welding ,law.invention ,Brittleness ,Mechanics of Materials ,law ,Electron beam welding ,Particle ,General Materials Science ,Cold welding ,Composite material - Abstract
The electron beam welding of SiCp/101Al composites has been carried out. The influence of welding parameters on weldability and mechanical properties of the welded joints was discussed. The welding parameters were therefore optimised under the current experimental circumstance. Results show that only weak interfacial reaction between SiC particle and liquid aluminium occurred. Minute quantity brittle Al4C3 compounds and single phase Si were generated in the welded joint. The interfacial reaction between SiC particles and Al matrix could be greatly suppressed by adopting appropriate technique measures such as high welding speed and low heat input. The content of Al4C3 can be therefore greatly decreased in the welded joint. Moreover, modification welding and electron beam scanning could further improve the appearance of weld, and the welded joint with better quality could be obtained.
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- 2011
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6. Structural and optical properties of wurtzite InN grown on Si(111)
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Hui Ying Yang, Shu Ping Lau, X. H. Ji, and Qinyuan Zhang
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Materials science ,Indium nitride ,Photoluminescence ,Metals and Alloys ,Surfaces and Interfaces ,Substrate (electronics) ,Surfaces, Coatings and Films ,Electronic, Optical and Magnetic Materials ,Amorphous solid ,chemistry.chemical_compound ,Crystallography ,symbols.namesake ,chemistry ,Materials Chemistry ,symbols ,Grain boundary ,Texture (crystalline) ,Raman spectroscopy ,Wurtzite crystal structure - Abstract
We report the structural and optical properties of InN films on Si(111) prepared by ion-beam-assisted filtered cathodic vacuum arc technique. X-ray diffraction and Raman spectroscopy measurements indicated that all the InN films were hexagonal crystalline InN. The InN films deposited at substrate temperature of 475 °C exhibited highly (0001) preferred orientation and texturing (cratered) surface morphology. The oxygen incorporated in the InN films was segregated in the form of amorphous indium oxide or oxynitride phases at the grain boundaries. Photoluminescence emission of ∼ 1.15 eV was observed at room temperature from the InN films.
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- 2007
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7. Aligned InN nanofingers prepared by the ion-beam assisted filtered cathodic vacuum arc technique
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X H Ji, Hui Ying Yang, Shu Ping Lau, and Siu Fung Yu
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Photoluminescence ,Materials science ,Ion beam ,business.industry ,Mechanical Engineering ,Analytical chemistry ,Bioengineering ,General Chemistry ,Vacuum arc ,Full width at half maximum ,Field electron emission ,Mechanics of Materials ,Optoelectronics ,General Materials Science ,Crystallite ,Electrical and Electronic Engineering ,business ,Current density ,Wurtzite crystal structure - Abstract
We report the synthesis of aligned wurtzite InN nanofingers by the ion-beam assisted filtered cathodic vacuum arc technique. InN nanofingers exhibit a polycrystalline structure. Photoluminescence (PL) and field emission properties of the InN nanofingers were studied. The PL emission peak was centred at ~1.1 eV with a full width at half maximum of 105 meV. The field emission characteristic was observed from the InN nanofingers with turn-on field of 9.7 V µm−1 at a current density of 10 µA cm−2. The formation of InN nanofingers was attributed to the Volmer–Weber growth mode.
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- 2005
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8. Structural properties and nanoindentation of AlN films by a filtered cathodic vacuum arc at low temperature
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Shu Ping Lau, Beng Kang Tay, W. H. Zhong, X. H. Ji, and G. Q. Yu
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Materials science ,Acoustics and Ultrasonics ,Aluminium nitride ,Analytical chemistry ,Vacuum arc ,Nitride ,Nanoindentation ,Condensed Matter Physics ,Surfaces, Coatings and Films ,Electronic, Optical and Magnetic Materials ,symbols.namesake ,chemistry.chemical_compound ,X-ray photoelectron spectroscopy ,chemistry ,Physical vapor deposition ,symbols ,Raman spectroscopy ,Diffractometer - Abstract
Aluminium nitride (AlN) films have been fabricated on Si(100) substrates by an ion-beam-assisted filtered cathodic vacuum arc technique at low temperature. The structural and mechanical properties of the AlN films have been investigated using x-ray photoelectron spectroscopy, by means of an x-ray diffractometer, visible Raman spectroscopy, atomic force microscopy and nanoindentation. The AlN films exhibit a predominant a-axis orientation with hardness as high as 14.5 GPa, which may be suitable for surface acoustic wave devices.
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- 2004
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9. Nitrogen-ion-energy dependent optical and structural properties of AlN films obtained using a filtered cathodic vacuum arc
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W. H. Zhong, Y G Wang, Shu Ping Lau, X. H. Ji, G. Q. Yu, and Beng Kang Tay
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Materials science ,Acoustics and Ultrasonics ,business.industry ,Aluminium nitride ,Vacuum arc ,Nitride ,Condensed Matter Physics ,Surfaces, Coatings and Films ,Electronic, Optical and Magnetic Materials ,Amorphous solid ,Condensed Matter::Materials Science ,symbols.namesake ,chemistry.chemical_compound ,Optics ,chemistry ,Physical vapor deposition ,symbols ,Optoelectronics ,Thin film ,business ,Raman spectroscopy ,Surface states - Abstract
We report on the successful fabrication of transparent and uniform aluminium nitride (AlN) III–V semiconductor films using an ion-beam assisted filtered cathodic vacuum arc technique at room temperature. A nitrogen-ion beam with energy varying from 200 to 650 eV has been employed to assist the deposition of AlN films. Effects of the nitrogen-ion-beam energy on optical and structural properties of AlN films have been investigated using an optical spectrophotometer, visible Raman spectroscopy, x-ray diffraction, atomic force microscopy and nanomechanical test instruments. The optical and structural properties of the AlN films depend significantly on the nitrogen-ion-beam energy. The AlN films deposited under ion energies below 300 eV are all amorphous and enhanced polycrystalline AlN films are obtained for energies above 400 eV.
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- 2003
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10. Mapping of quantitative trait loci for the bolting trait in Brassica rapa under vernalizing conditions
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Y G Wang, J F Yan, Xixi Lv, L J Zhang, Y T Liu, H Feng, and X H Ji
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education.field_of_study ,Bolting ,Breeding program ,Genetic Linkage ,Population ,Brassica rapa ,Quantitative Trait Loci ,Chromosome Mapping ,General Medicine ,Vernalization ,Biology ,Quantitative trait locus ,Breeding ,Agronomy ,Genetics ,Trait ,Cultivar ,education ,Molecular Biology ,Microsatellite Repeats - Abstract
Premature bolting can occur occasionally during spring cultivation of heading Chinese cabbage in East Asia when the plants encounter low temperatures (vernalization), leading to economic loss. Breeding bolting-resistant cultivars is the best choice for solving this problem. We looked for QTLs responsible for varietal differences in the bolting trait in Brassica rapa under environmental conditions that promote vernalization. To achieve this goal, we constructed a linkage map with 107 simple sequence repeats and 54 insertion/deletion markers based on a segregating population of 186 F2 individuals. The resulting map consisted of 10 linkage groups and covered a total length of 947.1 cM, with an average genetic distance of 5.84 cM between adjacent markers. QTL analysis of the bolting trait was performed by two phenotypic evaluations (bolting index and flowering time) based on the scores in an F2 population in the spring of 2010, and scores in F2:3 families in autumn 2010 and spring 2011, respectively. Twenty-six QTLs that controlled bolting were detected, accounting for 2.6 to 31.2% of the phenotypic variance. The detected QTLs with large effects co-localized mainly on linkage groups A02, A06, and A07. These QTLs may provide useful information for marker-assisted selection in a breeding program for late bolting or bolting-resistant cultivars in B. rapa crops.
- Published
- 2014
11. A fractal model for simulating the formation of microcracks in the fracture process zone and a theoretical explanation of the size effect of the fracture energy of concrete
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N. Q. Feng, X. H. Ji, and Y. N. Chan
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Cement ,Surface (mathematics) ,Materials science ,Fracture mechanics ,Building and Construction ,Fractal dimension ,Surface energy ,Fractal ,Fracture (geology) ,General Materials Science ,Geotechnical engineering ,Fracture process ,Composite material ,Civil and Structural Engineering - Abstract
A fractal model is presented for simulating the formation of microcracks in the fracture process zone of concrete. The model is used to calculate the fractal dimension D of a network of microcracks. It is found that the branching angle of microcracks can greatly affect the value of D, and a lower value of D can be expected for high-strength concrete than for normal-strength concrete. In the light of fractal theory, a formula for calculating the total area of the fracture surface. including the area of microcracks, is proposed. The size effect of the fracture energy of cement-based materials is explained and the quantitative relationship between the fracture energy Gf, the surface energy of the concrete γs, the fractal dimension of the network of microcracks Dc, and the height of the ligament of the concrete specimen H is established as Gf = 2γsC″HDc−1 (where C″ is a constant). Using this formula. the fra ctal dimension Dc, of the network of microcracks in high-strength and normal-strength concrete was determined experimentally.
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- 1997
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12. Relationship between urinary iodine and goiter prevalence: results of the Chinese national iodine deficiency disorders survey
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Shoujun Liu, S. B. Zhang, Xiaohui Su, Peipei Liu, and X. H. Ji
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medicine.medical_specialty ,China ,Goiter ,Adolescent ,Endocrinology, Diabetes and Metabolism ,Population ,Prevalence ,chemistry.chemical_element ,Iodine ,World health ,Endocrinology ,Internal medicine ,medicine ,Humans ,education ,Child ,education.field_of_study ,business.industry ,medicine.disease ,Nutrition Surveys ,Iodine deficiency ,Large sample ,chemistry ,Urinary iodine ,business ,Demography - Abstract
Background: In 1984, Yu Zhiheng proposed the “U-curve” regularity between urinary iodine (UI) and goiter prevalence (GP). However, along with the adjustment of salt iodine and iodine deficiency disorders (IDD), and surveys followed, some defects were found in the research. As a result, it is time to test and enrich the theory as a series of large sample survey data from China would be helpful. Aim: To test and enrich the theory of “U-curve” relationship between UI and GP. Subjects and methods: Based on the Chinese national IDD surveys (1999, 2002, 2005), the High Water Iodine survey of 2005, and the High Risk endemias survey of 2007, this article analyzed the relationship between UI and GP. The UI was grouped according to the World Health Organization (WHO) standard, self-defined (5 μg/l), and Yu Zhiheng’s level, separately, the GP was calculated for population with different UI level, the tendency curve was drawn and the fitting curve model was estimated by SPSS®. Results: For the 2005 Chinese national survey and 2005 High Water Iodine survey, we finally got the fitting curves and corresponding UI reference limits. Conclusions: The UI and GP formed a “U curve” relationship. It varied with some reasons and fell into an accurate U shape step by step. For High Water Iodine endemias survey, the relationship changed to “power curve”. Regarding the WHO recommended GP
- Published
- 2009
13. Magnetic properties and photoluminescence of undoped and transition metal doped A1N nanorods
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A. Sedhain, S.Y. Tang, Siu Fung Yu, Tun Seng Herng, Hui Ying Yang, X. H. Ji, Hongxing Jiang, Jingyu Lin, and Shu Ping Lau
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Photoluminescence ,Materials science ,Silicon ,business.industry ,Doping ,Analytical chemistry ,chemistry.chemical_element ,Magnetic semiconductor ,Magnetization ,Transition metal ,chemistry ,Impurity ,Optoelectronics ,Nanorod ,business - Abstract
The undoped and transition metal (TM) -doped AIN (AIN:Cu and AIN:Fe) nanorods on silicon substrates were fabricated using a catalysis-free vapor phase method. All the nanorods exhibited high crystalline quality and preferred c-axis orientation. Room-temperature photoluminescence (PL) measurement revealed that undoped AIN nanorods exhibited strong oxygen-related impurity emission at ~3.25 eV. However, AIN:Fe nanorods had two strong ultraviolet emissions at 3.69 and 6.02 eV which could be attributed to Fe 3+-related and band-edge emission, respectively. Both the Cu and Fe-doped AIN nanorods are ferromagnetic. The spontaneous saturated magnetization of the AIN:Cu and AIN:Fe nanorods were determined to be 0.38 and 3.5 emu/cm3 at room temperature, respectively. The Fe-doped AIN nanorods not only exhibited ferromagnetism but also significantly enhanced the band-edge emission as compared to the undoped AIN nanorods.
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- 2008
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14. Ultraviolet photoluminescence from ferromagnetic Fe-doped AlN nanorods
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Tun Seng Herng, Jingsheng Chen, Hui Ying Yang, Hongxing Jiang, Shu Ping Lau, X. H. Ji, Kar Seng Teng, Siu Fung Yu, Jingyu Lin, and A. Sedhain
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Materials science ,Photoluminescence ,Physics and Astronomy (miscellaneous) ,Silicon ,business.industry ,Analytical chemistry ,chemistry.chemical_element ,Magnetic semiconductor ,medicine.disease_cause ,Magnetization ,Ferromagnetism ,chemistry ,Fe doped ,medicine ,Optoelectronics ,Nanorod ,business ,Ultraviolet - Abstract
Fe-doped AlN (AlN:Fe) nanorods on silicon substrates were fabricated using a catalysis-free vapor phase method. The AlN:Fe nanorods exhibited high crystalline quality and preferred c-axis orientation. The spontaneous saturated magnetization of the AlN:Fe nanorods was determined to be ∼0.64μB∕Fe at room temperature. Room temperature photoluminescence measurement of the AlN:Fe nanorods revealed two strong ultraviolet emissions at 3.69 and 6.02eV which could be attributed to Fe3+-related and band edge emissions, respectively. The Fe-doped AlN nanorods not only exhibited ferromagnetism but also significantly enhanced the band edge emission as compared to the undoped AlN nanorods.
- Published
- 2007
15. Effects of Tripterygium wilfordii saponins and interleukin-10 on dendritic cells from human peripheral blood
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S J, Wang, K, Yao, F D, Xie, and X H, Ji
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Tripterygium ,B7-1 Antigen ,Leukocytes, Mononuclear ,Humans ,Cell Separation ,Dendritic Cells ,HLA-DR Antigens ,Saponins ,Flow Cytometry ,Cells, Cultured ,Immunosuppressive Agents ,Interleukin-10 - Abstract
To study the effects of Tripterygium wilfordii (TII) and IL-10 on human leukocyte antigen-DR (HLA-DR) and CD80 expressions and IL-12 p40 subunit production and transcription of dendritic cells (DC) in human peripheral blood from healthy volunteers in vitro.DC were generated by culturing plastic-adherent peripheral blood mononuclear cells with GM-colony stimulating factor (GM-CSF), IL-4, and TNFalpha. The expressions of HLA-DR and CD80 were examined by flow cytometry after the cells were stained with immunofluorescence antibodies. Enzyme-linked immunosorbent assay and reverse transcriptase polymerase chain reaction analysis were used to detect IL-12 p40 protein level and mRNA transcription, respectively.TII 5 - 20 mg/L and IL-10 50 - 200 microg/L greatly down-regulated the membrane expressions of HLA-DR and CD80 on DC in a concentration-dependent manner. IL-12 p40 production and mRNA transcription were also inhibited in DC both by TII and by IL-10.TII and IL-10 exert immunosuppressive role via inhibiting membrane expressions of HLA-DR and CD80 and synthesis of IL-12 p40 subunit in DC.
- Published
- 2001
16. Effects of rhM-CSF expressed in silkworm on cytokine productions and membrane molecule expressions of human monocytes
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X H, Ji, L H, Sun, J C, Qin, K, Yao, R N, Ding, H D, Li, and D X, Zhu
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Adult ,Interleukin-6 ,Tumor Necrosis Factor-alpha ,Macrophage Colony-Stimulating Factor ,Interleukin-8 ,Receptors, IgG ,Leukocytes, Mononuclear ,Animals ,Humans ,Bombyx ,Recombinant Proteins - Abstract
To study the effects of recombinant human macrophage colony-stimulating factor (rhM-CSF) expressed in silkworm on cytokine productions and membrane molecule expressions of monocytes.The rhM-CSF was added to the human peripheral blood monocyte cultures and 3 d later, the culture supernatants and cells were collected, respectively. TNF-alpha, IL-6, IL-8, and IFN-alpha levels in the supernatants were detected by biological activity test or ELISA and expressions of CD11b, CD16, HLA I, and HLA II on the cellular surface were examined by the method of alkaline phosphatase anti-alkaline phosphatase complex (APAAP).The rhM-CSF promoted TNF-alpha, IL-6, and IL-8 inductions of monocytes and increased the percentages of CD11b, CD16, HLA I, and HLA II molecule expression on monocytes.The rhM-CSF plays a role in monocyte function up-regulation and has a certain practical value in immunological therapy.
- Published
- 2001
17. Local Atomic and Electronic Structure of the Fe dopants in AlN:Fe Nanorods
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D. S. Chub, Yan V. Zubavichus, Shu Ping Lau, Alexander V. Soldatov, V. L. Mazalova, X. H. Ji, and Alexander A. Guda
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History ,Crystallography ,Photoluminescence ,Materials science ,Dopant ,Absorption spectroscopy ,Nanorod ,FEAL ,Electronic structure ,Spectroscopy ,Crystallographic defect ,Computer Science Applications ,Education - Abstract
Fe-doped AlN nanorods were studied by means of x-ray absorption spectroscopy above the Fe K- and L2,3- edges. Theoretical simulations of the x-ray absorption spectra show that Fe atoms mainly substitute Al. A minor fraction of Fe interstitials or Fe-Al-N ternary alloy can be identified as well. Bader's AIM analysis predicts that neutral substitutional FeAl defect is in 2+ charge state, though Al in pure AlN is in 3+ charge state. Fe L2,3 absorption spectra and photoluminescence data indicate the coexistence of Fe2+/Fe3+ in AlN:Fe nanorods so different charge states of substitutional FeAl should co-exist.
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- 2013
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18. The use of dot-immunogold-silver staining (dot-IGSS), dot-ELISA and dot-IGSS to detect serum antibodies from clonorchiasis patients: a comparative study
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Z X, Wu, W P, Du, Y W, Rong, X H, Ji, and S Y, Yuan
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Antibodies, Helminth ,Clonorchiasis ,Humans ,Enzyme-Linked Immunosorbent Assay ,Immunohistochemistry ,Sensitivity and Specificity - Abstract
We report the use of immunogold-silver staining (IGSS), dot-ELISA and dot-IGSS methods in the study of clonorchiasis in China. These methods were employed to detect the antibody in sera from 40 clonorchiasis patients. The positive rates were 100%, 90.0% and 95.0%, respectively. When the three methods were used to examine 40 normal sera, the negative rates were 100%, 97.5% and 97.5%, respectively. These results suggest that IGSS, dot-ELISA and dot-IGSS are highly specific and sensitive in detecting anti-Clonorchis antibody in patients.
- Published
- 1993
19. [Effects of extracts from Phyllanthus urinaria L. on HBsAg production in PLC/PRF/5 cell line]
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X H, Ji, Y Z, Qin, W Y, Wang, J Y, Zhu, and X T, Liu
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Carcinoma, Hepatocellular ,Hepatitis B Surface Antigens ,Liver Neoplasms ,Tumor Cells, Cultured ,Humans ,Vidarabine ,Drugs, Chinese Herbal - Abstract
Experiment on the effect of extracts from Phyllanthus urinaria on HBsAg production in PLC/PRF/5 human hepatoma cell line showed that the production was decreased markedly 48 hours after the treatment of cells with 2-4 mg/ml Phyllanthus urinaria, especially in combination with 10(-5) mol/L of Ara-A. The decrease of extracellular HB-sAg excretion seems to stem from the inhibition of intracellular HBsAg formation.
- Published
- 1993
20. Stress and its effect on optical properties of AlN nanorods
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Shu Ping Lau, Z. Y. Ling, Qinyuan Zhang, and X. H. Ji
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Materials science ,Photoluminescence ,Physics and Astronomy (miscellaneous) ,Condensed matter physics ,business.industry ,Phonon ,Physics::Optics ,Thermal expansion ,Stress (mechanics) ,Condensed Matter::Materials Science ,symbols.namesake ,Laser linewidth ,Optics ,symbols ,Nanorod ,business ,Raman spectroscopy ,Raman scattering - Abstract
The stress states in AlN nanorods deposited on Si and its effect on optical properties have been investigated by means of Raman scattering and photoluminescence methods. The observed frequency downshift and linewidth broadening from temperature-dependent Raman scattering can be well described by an empirical relationship taking into account the contributions of the thermal expansion and decay of optical phonons. The phonon-energy difference of the E2(high) mode between the stress-free bulk-AlN and AlN nanorods appears to increase with increasing temperature, demonstrating that differential thermal expansion between the Si-substrate and AlN nanorods is the key parameter reflecting the stress in the nanorods.
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- 2009
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21. Copper defects inside AlN:Cu nanorods – XANES and LAPW study
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Mikhail A. Soldatov, Alexander V. Soldatov, N. Yu. Smolentsev, X. H. Ji, Alexander A. Guda, Shu Ping Lau, and V. L. Mazalova
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History ,X-ray spectroscopy ,Materials science ,Extended X-ray absorption fine structure ,Absorption spectroscopy ,Analytical chemistry ,chemistry.chemical_element ,Copper ,XANES ,Computer Science Applications ,Education ,X-ray absorption fine structure ,Condensed Matter::Materials Science ,Crystallography ,chemistry ,Nanorod ,Spectroscopy - Abstract
AlN ferromagnetic nanorods with 5 at.% of copper were studied by using x-ray absorption spectroscopy (XAFS) above the Cu K- and L3- edges. Theoretical simulations of XAFS spectra clearly identify a formation of small copper clusters inside AlN lattice. Average size of clusters was estimated to be 50–70 atoms from the analysis of both XANES (X-ray Absorption Near Edge Spectroscopy) and EXAFS (Extended X-ray Absorption Fine Structure) regions of spectra. Calculations of magnetic moments for different types of point copper defects in AlN lattice were made.
- Published
- 2009
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22. Temperature-dependent photoluminescence and electron field emission properties of AlN nanotip arrays
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X. H. Ji, Hongxing Jiang, Qinyuan Zhang, Jingyu Lin, and Shu Ping Lau
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Photoluminescence ,Materials science ,Physics and Astronomy (miscellaneous) ,Field (physics) ,business.industry ,Nanostructured materials ,Wide-bandgap semiconductor ,medicine.disease_cause ,Field electron emission ,Electric field ,Electron current ,medicine ,Optoelectronics ,business ,Ultraviolet - Abstract
Large-scale single-crystalline AlN nanotip arrays have been fabricated via a facile catalysis-free approach using AlCl3 powder and NH3 as starting materials. These nanotips exhibit an intense broad ultraviolet emission centered at 3.28 eV. The field emission features a notable electron current with a low turn-on field. The turn-on and threshold electric field are found to decrease substantially from 7.7 to 3.9 V/μm and 7.9 to 4.1 V/μm, respectively, while the estimated field enhancement factor increases from 483 to 1884 with increasing the ambient-temperature from room temperature to 573 K. The dependence of the photoluminescence and electron field emission with temperature and the possible mechanism involved has systematically been investigated and thus discussed.
- Published
- 2009
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23. Distribution and excretion of 3H-sterigmatocystin in rats
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D S, Wang, H L, Sun, F Y, Xiao, X H, Ji, Y X, Liang, and F G, Han
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Male ,Sterigmatocystin ,Animals ,Rats, Inbred Strains ,Tissue Distribution ,Tritium ,Rats - Abstract
In order to investigate the distribution and excretion of sterigmatocystin, a carcinogenic mycotoxin, radioactively labelled compound was studied in rats. The highest concentration of radioactivity in serum appeared 3 h after administration of 0.5 microCi/g bw. The half-lives of distribution and excretion were 0.51 h and 43.9 h, respectively. The radioactivity was concentrated mainly in liver, stomach, kidney, duodenum and lung and to a lesser extent in fat, muscle, testis, rectum and bone. By 48 h, 56.4% had been excreted in faeces and 20.1% in urine. Biliary excretion may be the major route of excretion of sterigmatocystin.
- Published
- 1991
24. Ferromagnetic Cu-doped AlN nanorods
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Jingsheng Chen, Tun Seng Herng, Shu Ping Lau, Hui Ying Yang, Siu Fung Yu, and X H Ji
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Materials science ,Condensed matter physics ,Dopant ,Mechanical Engineering ,Analytical chemistry ,Bioengineering ,General Chemistry ,Coercivity ,Magnetization ,Surface coating ,Ferromagnetism ,Mechanics of Materials ,General Materials Science ,Nanorod ,Electrical and Electronic Engineering ,Spontaneous magnetization ,Wurtzite crystal structure - Abstract
Copper-doped AlN (AlN:Cu) nanorods were grown on catalyst-free Si substrates by chemical vapour deposition. The AlN:Cu nanorods exhibited the wurtzite structure with a growth direction along the c-axis. Ferromagnetic ordering of the AlN:Cu nanorods was observed at room temperature by an alternating gradient magnetometer. The spontaneous magnetization and the coercivity of the AlN:Cu nanorods are about 0.38?emu?cm?3 and 100?Oe, respectively. The results reveal that Cu is a potential nonmagnetic dopant for AlN.
- Published
- 2007
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25. Discussion: A fractal model for simulating the formation of microcracks in the fracture process zone and a theoretical explanation of the size effect of the fracture energy of concrete
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X. H. Ji, Y. N. Chan, N. Q. Feng, A. Carptinteri, and B. Chiaia
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General Materials Science ,Building and Construction ,Civil and Structural Engineering - Published
- 1998
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26. Origin of room temperature ferromagnetism in ZnO:Cu films
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Nobuto Yasui, Tun Seng Herng, Hui Ying Yang, Siu Fung Yu, Hiroshi Inaba, X. H. Ji, Jingsheng Chen, and Shu Ping Lau
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Materials science ,Quantitative Biology::Neurons and Cognition ,Silicon ,Condensed matter physics ,Condensed Matter::Other ,Analytical chemistry ,General Physics and Astronomy ,chemistry.chemical_element ,Magnetic semiconductor ,Copper ,Condensed Matter::Materials Science ,Magnetization ,X-ray photoelectron spectroscopy ,chemistry ,Ferromagnetism ,Transmission electron microscopy ,X-ray crystallography ,Physics::Atomic and Molecular Clusters - Abstract
Copper-doped ZnO (ZnO:Cu) films were prepared on silicon substrates by filtered cathodic vacuum arc technique at room temperature using a Zn target containing 5at.% of Cu. Room temperature ferromagnetism was observed in the ZnO:Cu films with saturation magnetization of 0.037μB∕Cu atom. The origin of the ferromagnetism in ZnO:Cu was mainly due to Cu ions substituted into the ZnO lattice. X-ray diffraction, x-ray photoelectron spectroscopy, and transmission electron microscopy revealed that no ferromagnetic-related secondary phase could be detected in ZnO:Cu.
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- 2006
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27. 980nm laser-diode-excited intense blue upconversion in Tm3+∕Yb3+-codoped gallate–bismuth–lead glasses
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Q. Y. Zhang, Z. H. Jiang, X. H. Ji, S. Buddhudu, and T. Li
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education.field_of_study ,Materials science ,Physics and Astronomy (miscellaneous) ,Laser diode ,Phonon ,business.industry ,Population ,chemistry.chemical_element ,Photon upconversion ,law.invention ,Photoexcitation ,Thulium ,chemistry ,law ,Excited state ,Optoelectronics ,Absorption (electromagnetic radiation) ,education ,business - Abstract
Intense blue-upconversion in Tm3+∕Yb3+-codoped gallate–bismuth–lead glasses has been achieved under an excitation from a commercially available 980nm laser diode. Energy transfer processes and excited-state absorption account for the population of the G41 emitting level of the Tm3+. Although the addition of GeO2 has enhanced the glass thermal stability, the phonon mode associated with vibration of GeO2 has almost no influence on the blue-upconversion intensity and the radiative lifetime of H43 level. The dependence of the phonon energy of the host on contributions from multiphonon decay on the fluorescence has been discussed. Significant enhancement of the blue-upconversion has also been observed in gallate–bismuth–lead glasses with the incorporation of PbF2 content.
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- 2005
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28. Effects of different space allowances on growth performance, blood profile and pork quality in a grow-to-finish production system
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J. C. Jang, X. H. Jin, J. S. Hong, and Y. Y. Kim
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Space Allowance ,Growing-finishing Pigs ,Growth Performance ,Immune ,Pork Quality ,Animal culture ,SF1-1100 ,Animal biochemistry ,QP501-801 - Abstract
Objective This experiment was conducted to evaluate the optimal space allowance on growth performance, blood profile and pork quality of growing-finishing pigs. Methods A total of ninety crossbred pigs [(Yorkshire×Landrace)×Duroc, 30.25±1.13 kg] were allocated into three treatments (0.96: four pigs/pen, 0.96 m2/pig; 0.80: five pigs/pen, 0.80 m2/pig; 0.69: six pigs/pen, 0.69 m2/pig) in a randomized complete block design. Pigs were housed in balanced sex and had free access to feed in all phases for 14 weeks (growing phase I, growing phase II, finishing phase I, and finishing phase II). Results There was no statistical difference in growing phase, but a linear decrease was observed on average daily gain (ADG, p
- Published
- 2017
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29. Effect of dietary energy levels and phase feeding by protein levels on growth performance, blood profiles and carcass characteristics in growing-finishing pigs
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J. S. Hong, G.I. Lee, X. H. Jin, and Y. Y. Kim
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Energy ,Growing-finishing pig ,Growth performance ,Phase feeding ,Protein ,Animal culture ,SF1-1100 - Abstract
Abstract Background Providing of insufficient nutrients limits the potential growth of pig, while feeding of excessive nutrients increases the economic loss and causes environment pollution. For these reasons, phase feeding had been introduced in swine farm for improving animal production. This experiment was conducted to evaluate the effects of dietary energy levels and phase feeding by protein levels on growth performance, blood profiles and carcass characteristics in growing-finishing pigs. Methods A total of 128 growing pigs ([Yorkshire × Landrace] × Duroc), averaging 26.62 ± 3.07 kg body weight, were assigned in a 2 × 4 factorial arrangement with 4 pigs per pen. The first factor was two dietary energy level (3,265 kcal of ME/kg or 3,365 kcal of ME/kg), and the second factor was four different levels of dietary protein by phase feeding (1growing(G)-2finishing(F) phases, 2G-2F phases, 2G-3F phases and 2G-3F phases with low CP requirement). Results In feeding trial, there was no significant difference in growth performance. The BUN concentration was decreased as dietary protein level decreased in 6 week and blood creatinine was increased in 13 week when pigs were fed diets with different dietary energy level. The digestibility of crude fat was improved as dietary energy levels increased and excretion of urinary nitrogen was reduced when low protein diet was provided. Chemical compositions of longissimus muscle were not affected by dietary treatments. In backfat thickness (P2) at 13 week, pigs fed high energy diet had thicker backfat thickness (P = 0.06) and pigs fed low protein diet showed the trend of backfat thinness reduction (P = 0.09). In addition, water holding capacity was decreased (P = 0.01) and cooking loss was increased (P = 0.07) as dietary protein level reduced. When pigs were fed high energy diet with low subdivision of phase feeding, days to 120 kg market weight was reached earlier compared to other treatments. Conclusion Feeding the low energy diet and subdivision of growing-finishing phase by dietary protein levels had no significant effect on growth performance and carcass characteristics. Also, phase feeding with low energy and low protein diet had no negative effects on growth performance, carcass characteristics but economical profits was improved.
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- 2016
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30. Supplementation of Dried Mealworm ( larva) on Growth Performance, Nutrient Digestibility and Blood Profiles in Weaning Pigs
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X. H. Jin, P. S. Heo, J. S. Hong, N. J. Kim, and Y. Y. Kim
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Dried Mealworm ,Growth Performance ,Insect ,Larva ,Weaning Pigs ,Animal culture ,SF1-1100 ,Animal biochemistry ,QP501-801 - Abstract
This experiment was conducted to investigate the effects of dried mealworm (Tenebrio molitor larva) on growth performance, nutrient digestibility and blood profiles in weaning pigs. A total of 120 weaning pigs (28±3 days and 8.04±0.08 kg of body weight) were allotted to one of five treatments, based on sex and body weight, in 6 replicates with 4 pigs per pen by a randomized complete block design. Supplementation level of dried mealworm was 0%, 1.5%, 3.0%, 4.5%, or 6.0% in experimental diet as treatment. Two phase feeding programs (phase I from 0 day to 14 day, phase II from 14 day to 35 day) were used in this experiment. All animals were allowed to access diet and water ad libitum. During phase I, increasing level of dried mealworm in diet linearly improved the body weight (p
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- 2016
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31. Ferromagnetic Cu-doped AlN nanorods.
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X H Ji, S P Lau, S F Yu, H Y Yang, T S Herng, and J S Chen
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VAPOR-plating , *CHEMICAL vapor deposition , *COPPER , *METAL organic chemical vapor deposition - Abstract
Copper-doped AlN (AlN:Cu) nanorods were grown on catalyst-free Si substrates by chemical vapour deposition. The AlN:Cu nanorods exhibited the wurtzite structure with a growth direction along the c-axis. Ferromagnetic ordering of the AlN:Cu nanorods was observed at room temperature by an alternating gradient magnetometer. The spontaneous magnetization and the coercivity of the AlN:Cu nanorods are about 0.38 emu cm?3and 100 Oe, respectively. The results reveal that Cu is a potential nonmagnetic dopant for AlN. [ABSTRACT FROM AUTHOR]
- Published
- 2007
- Full Text
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