461 results on '"Xiao-xia Li"'
Search Results
202. Effects of Different Lipid Sources on the Growth Performance and Muscle Fatty Acid Composition of Juvenile Anguilla marmorata
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Li Liu Zhou, Li Liu, Guang jun Wang, Xiao-xia Li, Gui feng Li, Xue Ming Dan, Lian Gan, Shao Xuan Zhu, and Hui-juan Tang
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chemistry.chemical_classification ,food.ingredient ,Sunflower oil ,food and beverages ,Aquatic Science ,Biology ,Fish oil ,Soybean oil ,Vegetable oil ,Animal science ,food ,chemistry ,medicine ,Peanut oil ,medicine.symptom ,Agronomy and Crop Science ,Weight gain ,Corn oil ,Polyunsaturated fatty acid - Abstract
The aim of this study was to investigate the effects of different oils on growth performance of juvenile Anguilla marmorata. Five isonitrogenous and isoenergetic experimental diets were formulated to contain fish oil (FO), sunflower oil (SFO), peanut oil (PO), corn oil (CO) and soybean oil (SBO), respectively, as lipid sources each at an inclusion level of 50 g/kg. The diets were fed to apparent satiation for 10 weeks, twice a day to triplicate tanks of 30 fish each with an initial body weight 6.00±0.06 g. Weight gain (WG) and specific growth rate (SGR) of fish fed the FO and SBO diets were markedly higher than those fed the CO diet, while no other difference in WG and SGR were observed among other treatments. Fish fed FO and SBO diets had better feed utilization than the other diet fish groups. Muscle of fish fed the FO diet had significantly higher levels of C20:5n-3 and n-3/n-6 ratio compared with fish fed vegetable oil (VO) diets, while muscle n-6 PUFA and C18:2n-6 content showed an opposite trend. The present results suggest that soybean oil is a suitable replacement for fish oil for Anguilla marmorata. The IJA appears exclusively as a peer-reviewed on-line open-access journal at http://www.siamb.org.il. To read papers free of charge, please register online at registration form. Sale of IJA papers is strictly forbidden.
- Published
- 2017
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203. Friction Correction and Constitutive Equation of a Non-Quenched and Tempered Steel during Hot Deformation
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Ming Yao Li, Xiaochun Wu, Xiao Xia Li, and Xia Li
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Materials science ,Flow (mathematics) ,Metallurgy ,Hyperbolic function ,Constitutive equation ,General Engineering ,Mechanics ,Tempering ,Deformation (meteorology) ,Flow stress ,Forging - Abstract
Thermo-mechanical experiments were carried out to study the effect of deformation speed and temperature on the behaviour of a non-quenched and tempered steel during hot forging. And an effective method for correction of friction was used to amend the tested flow stress, Meanwhile, the constitutive equations of flow stress-strain for TL1438 steel during hot forming was established based on the amended flow stress and hyperbolic sine which includes Zener-Hollomon parameter, and related parameters of TL1438 during hot forming was obtained by analyzing the data.
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- 2013
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204. Effects of 5-aza-2’-deoxyctidine on the development of porcine parthenogenetic and nuclear transfer embryos
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Dong Kyo Kim, Xiao Xia Li, Kenji Naruse, Dong Ii Jin, Yun Fei Diao, Tao Lin, and Rong Xun Han
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Fetus ,medicine.anatomical_structure ,embryonic structures ,DNA methylation ,medicine ,Embryo ,Blastocyst ,Parthenogenesis ,Short exposure ,Biology ,Fibroblast ,Molecular biology ,In vitro - Abstract
The current study was to investigate whether embryo or fetal fibroblast cells treated with 5-aza-2’-deoxyctidine (5-aza-dC) have a positive effect on the in vitro development of porcine parthenogenetic and cloned embryos. To this end, porcine fetal fibroblast cells were treated with different concentrations (5 nM, 50 nM and 500 nM) of 5-aza-dC for different exposure times (1, 6 and 20 hours), the results showed that DNA methylation in PRE-1 SINE region was gradually reduced over time in cells treated with 5-aza-dC. To determine the effect of 5-aza-dC on in vitro development of porcine activated oocytes, the parthenogenetic embryo was treated with 5-aza- dC. Notably, treatment with 5 nM 5-aza-dC for 1 hour led to a significant improvement in blastocyst development, compared with the control group. The effects of donor cell treatment with 5-aza-dC on porcine cloned embryos development were further examined by treating fetal fibroblast cells with various concentrations (5 nM, 50 nM and 500 nM) of 5-aza-dC for different exposure times (1, 6 and 20 hours). Exposure of cells in 5 nM 5-aza-dC for 1 - 20 hours led to a significant improvement in the percentage of developed blastocysts, while treatment with 500 nM 5-aza-dC did not affect blastocyst development, compared to untreated controls. These findings indicate that treatment of fetal fibro-blast cells with relatively low concentrations of 5-aza-dC for short exposure times improves subsequent blastocyst development of porcine cloned embryos.
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- 2013
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205. Leptin and nonessential amino acids enhance porcine preimplantation embryo development in vitro by intracytoplasmic sperm injection
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Dong Soo Lee, Keun Jung Kim, Ji Hey Lee, Eun Young Kim, Jie Yeun Park, Xiao Xia Li, and Min Kyu Kim
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Leptin ,Male ,medicine.medical_specialty ,Swine ,Offspring ,medicine.medical_treatment ,Embryonic Development ,Gene Expression ,Apoptosis ,Reproductive technology ,Biology ,Intracytoplasmic sperm injection ,Animals, Genetically Modified ,Embryo Culture Techniques ,Food Animals ,Internal medicine ,medicine ,Animals ,Sperm Injections, Intracytoplasmic ,Blastocyst ,Amino Acids ,Small Animals ,reproductive and urinary physiology ,urogenital system ,Equine ,Embryogenesis ,Embryo ,Culture Media ,Endocrinology ,medicine.anatomical_structure ,Terminal deoxynucleotidyl transferase ,embryonic structures ,Female ,Animal Science and Zoology - Abstract
Intracytoplasmic sperm injection (ICSI) has been considered one of the strong assisted reproductive technologies for producing transgenic animals as well as treating infertility in animals and humans. However, in porcine ICSI, embryos produced by in vitro methods show low pregnancy rates with high abnormal offspring and blastocyst formation rate as well as quality are poor compared with those in other species. For these reasons, developing a protocol for porcine ICSI is essential to efficiently generate transgenic pigs. Since amino acids were introduced to embryo development because of their beneficial effects, many embryologists have been using nonessential amino acid (NEAA) in culture medium for embryonic development in pig and other species. Leptin also has been shown to be beneficial in embryonic development for increasing rate of cleavage and blastocyst development. However, the effects of NEAA and leptin were not fully understood in the development of porcine ICSI-derived embryos. Here we investigated the optimization of NEAA and leptin supplementation in culture medium to improve developmental competence and quality of preimplantation embryos after ICSI in pig. The proportion of embryos that developed to the blastocyst stage was significantly greater when 1% vol/vol NEAA (24.6%) or 100 ng/mL leptin (27.1%) was supplemented in the culture medium compared with other concentrations or no supplement. When NEAA and leptin (24.8%) were supplemented together, blastocyst formation was significantly higher than other single supplementation groups. We also evaluated the effects of different supplementation periods of NEAA or leptin on the preimplantation embryonic development after ICSI. Both NEAA and leptin showed that supplementation for the entire 7 days significantly increased the blastocyst formation rate compared with the other groups of supplementation for the first 4 days and for the subsequent 3 days. A second goal of our research was to evaluate the quality of developed blastocysts after ICSI. The supplementation of 100 ng/mL leptin in culture medium made blastocysts express less of the proapoptosis genes BAX and BAK and more of the antiapoptosis genes BCL-XL and BCL-2 after the ICSI procedure. Furthermore, terminal deoxynucleotidyl transferase dUTP nick end labeling index, fragmentation, and total apoptosis were significantly decreased and the total cell number was significantly increased when the ICSI-derived embryos were cultured to blastocyst stage in the presence of the combination of NEAA and leptin. These results suggest that NEAA and leptin could improve not only the quantity but also quality of ICSI-derived porcine embryos during in vitro culture with the optimal concentration of each reagent.
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- 2013
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206. Numerical calculation of the plume infrared radiation of a long-endurance UAV
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Zhang-bin Huang, Xiao-xia Li, and Yun-song Feng
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Core (optical fiber) ,Field (physics) ,law ,Infrared ,Flow (psychology) ,Eddy current ,Environmental science ,Radiation ,Energy (signal processing) ,law.invention ,Remote sensing ,Plume - Abstract
Plume is the main infrared source of a long-endurance UAV, and its infrared radiation numerical calculation is very important for calculating the infrared characteristcs of the whole UAV. This paper built the geometrical model of the flow field structure of UAV plume by analyzing the characteristcs of the flow structure. And, The temperaturre field distribution of the UAV plume was calculated based on the eddy current propagation theory. And then, spectral infrared radiation characteristics of the UAV plume at 2-5μm were obtained by the single band C-G approximation method. The results show that the temperature in the core area of the UAV plume is higher , and the infared radiation characteristics are stable and obvious. The infrared radiation energy of the plume mainly ditributed at the infrared wavelength of 2.7μm and 4.5μm,which is in accordance with the actual situation. The results maybe contribute to the further study of the infrared radiation characteristics of the long-endurance UAV.
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- 2016
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207. ChemInform Abstract: New Antibacterial Isocoumarin Glycosides from a Wetland Soil Derived Fungal Strain Metarhizium anisopliae
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Peng Huang, Xin Sheng Yao, Hao Gao, Peng Ju Li, Xiao-Xia Li, Xingzhong Liu, Jin-Shan Tang, Ping Hua Sun, and Jie Feng Tian
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chemistry.chemical_classification ,Circular dichroism ,biology ,Strain (chemistry) ,Stereochemistry ,Metarhizium anisopliae ,Glycoside ,General Medicine ,Carbon-13 NMR ,biology.organism_classification ,Isocoumarin ,chemistry.chemical_compound ,chemistry ,Antibacterial activity ,Derivatization - Abstract
Eight new isocoumarin glycosides (1-8) were obtained from the solid culture of the wetland soil-derived fungus Metarhizium anisopliae (No. DTH12-10). Their chemical structures were elucidated by analyses of HR ESI-TOF MS, (1)H, (13)C NMR, (1)H-(1)H COSY, HSQC, and HMBC spectra. The absolute configurations were determined by single crystal X-ray diffraction, circular dichroism (CD) spectrum, and chemical derivatization methods. In addition, inhibition of the biofilm formation and the secretion of virulence factor of the new isocoumarin glycosides against Pseudomonas aeruginosa strain PAOA (clinical isolates) were evaluated. The result revealed that compound 1 showed antibacterial activity comparable with (Z)-4-bromo-5-(bromomethylene)-2(5H)-furanone (BF).
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- 2016
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208. Synthetic access to poly-substituted 6-alkoxyindoles from 1,3-cyclohexanediones and nitroolefins through facile aromatization reaction
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Li-Jian Ma, Xiao-Xia Li, Kusuyama, Tomoyo, El-Sayed, Ibrahim El-Tantawy, and Inokuchi, Tsutomu
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Acetylation -- Usage ,Cyclohexane -- Chemical properties ,Cyclohexane -- Structure ,Styrene -- Chemical properties ,Styrene -- Structure ,Biological sciences ,Chemistry - Abstract
The article explains a new synthetic approach, which employs the facile aromatization reaction for the development of the poly-substituted 6-alkaoxyindoles from 1, 3-cyclohexanediones and nitroolefines. The approach is shown to be extremely easy, simple and efficient.
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- 2009
209. Density functional theory studies of [Au.sub.n+](C[H.sub.3]OH)m (n = 3, 5, m = 1?5) complexes
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Ying-Chun Li, Chuan-Lu Yang, Mei-Yu Sun, Xiao-Xia Li, Yi-Peng An, Mei-Shan Wang, Xiao-Guang Ma, and De-Hua Wang
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Gold -- Properties ,Gold -- Research ,Methanol -- Research ,Ions -- Research ,Absorption -- Research ,Chemicals, plastics and rubber industries - Published
- 2009
210. Research on Software Interface Testing Technology Based on CAN Bus
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Liang Xiang, Song Yang Du, Zhong Wei Chen, and Xiao Xia Li
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Computer science ,business.industry ,Interface (computing) ,ComputerApplications_COMPUTERSINOTHERSYSTEMS ,General Medicine ,Graphical user interface testing ,CAN bus ,Software ,Embedded system ,Software construction ,Software reliability testing ,business ,Control bus ,System software - Abstract
This paper firstly introduces the basic information of CAN bus and the general method of CAN testing and points out that application layer protocol is hard to test. Secondly, this paper adapts the method of capturing, analyzing, constructing and sending CAN bus data packet to analyze certain oil system software interface protocol. Then, this paper proves this method can be usde to test the accuracy of the software interface and conduct the further software interface testing.At last,this paper points out the application suggest of this method.
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- 2012
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211. Two new naphthalene derivatives from an endolichenic fungal strainScopulariopsissp
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Fan Yang, Guo-Dong Chen, Xin-Sheng Yao, Liang-Dong Guo, Hao Gao, Xiao-Xia Li, and Yang Wu
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Pharmacology ,China ,Lichens ,Molecular Structure ,biology ,Chemistry ,Stereochemistry ,Organic Chemistry ,Pharmaceutical Science ,General Medicine ,Naphthalenes ,biology.organism_classification ,Isolation (microbiology) ,Analytical Chemistry ,chemistry.chemical_compound ,Complementary and alternative medicine ,Scopulariopsis ,Drug Discovery ,Molecular Medicine ,Fungal strain ,Organic chemistry ,Nuclear Magnetic Resonance, Biomolecular ,Two-dimensional nuclear magnetic resonance spectroscopy ,Naphthalene - Abstract
Chemical investigation on an endolichenic fungal strain Scopulariopsis sp. led to the isolation of two new naphthalene derivatives, 1-(4'-hydroxy-3',5'-dimethoxy-phenyl)-1,8-dimethoxynaphthalen-2(1H)-one (1) and 1,8-dimethoxynaphthalen-2-ol (2). Their structures were determined by spectroscopic techniques (UV, IR, MS, 1D, and 2D NMR).
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- 2012
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212. Study on the Hot Stamping Process of DP Steel Engine Dumping Plank Based on FEM
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Shao Bo Ping, Rui Hua Dong, Han Wu Liu, and Xiao Xia Li
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Engineering ,Computer simulation ,business.industry ,Process (computing) ,Formability ,General Medicine ,Structural engineering ,Hot stamping ,Stamping ,business ,Blank ,Plank ,Finite element method - Abstract
In order to lessen the worsened formability, failures and fractures occurring in the cold stamping process, the hot stamping technology was adopted in the forming of DP steel engine dumping plank. The simulation technology of finite element method was also used to forecast the forming defects in the stamping process of the DP steel engine dumping plank. In the paper, the forming limit, the influences of stamping gaps and the influences of different blank holder force on the stamping part were analyzed by using eta/DYNAFORM software. Meanwhile, the thickness changes and the materials flow conditions of the DP plank during the hot stamping process were also analyzed. Through the experimental analysis, the result of the finite element numerical simulation complied very well with that of actual production results. The research results show that duplex steel plate can meet the performance requirements of car engine dumping plank forming, which offers theory basis for the production of similar parts.
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- 2012
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213. Transient electro-osmotic flow of generalized Maxwell fluids through a microchannel
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Xiao-Xia Li, Long Chang, Quansheng Liu, Yongjun Jian, Jie Su, and Ze Yin
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Physics ,Microchannel ,Laplace transform ,Cauchy momentum equation ,Applied Mathematics ,Mechanical Engineering ,General Chemical Engineering ,Microfluidics ,Constitutive equation ,Condensed Matter Physics ,Physics::Fluid Dynamics ,Classical mechanics ,Flow (mathematics) ,Newtonian fluid ,General Materials Science ,Transient (oscillation) - Abstract
Non-Newtonian fluids such as blood, colloids, and cell suspensions are often manipulated in microfluidic devices and exhibit extraordinary flow behaviors, not existing in Newtonian fluids. This paper represents an analytical solution of transient velocity for electroosmotic flow of generalized Maxwell fluids through both a micro-parallel channel and a microtube, using the method of Laplace transform. The solution involves analytically solving the linearlized Poisson–Boltzmann equation, together with the Cauchy momentum equation and the general Maxwell constitutive equation. By numerical computations, the influence of normalized relaxation time on transient EOF velocity is investigated for different parametric values.
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- 2012
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214. New Azaphilones and Chlorinated Phenolic Glycosides from Chaetomium elatum with Caspase-3 Inhibitory Activity
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Ying Chen, Liang-Dong Guo, Ying-Zhou Cen, Xin-Sheng Yao, Jia Li, Xiao-Xia Li, Yan-Jun Li, Guo-Dong Chen, and Hao Gao
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Cell Extracts ,Models, Molecular ,Magnetic Resonance Spectroscopy ,Halogenation ,Stereochemistry ,Pharmaceutical Science ,Caspase 3 ,Chaetomium ,Crystallography, X-Ray ,Analytical Chemistry ,Inhibitory Concentration 50 ,Phenols ,Drug Discovery ,Benzopyrans ,Glycosides ,Chaetomiaceae ,Medicine, Chinese Traditional ,Pharmacology ,chemistry.chemical_classification ,Molecular Structure ,biology ,Chemistry ,Organic Chemistry ,Glycoside ,Pigments, Biological ,Chaetomium elatum ,biology.organism_classification ,Caspase Inhibitors ,Recombinant Proteins ,Enzyme ,Complementary and alternative medicine ,Molecular Medicine ,Fungal strain ,Cysteine - Abstract
Three new azaphilones, chaetomugilin S (1), 7,5'-bis-epi-chaetoviridin A (2), and 7-epi-chaetoviridin E (3), and two new chlorinated phenolic glycosides, globosumoside A (4) and globosumoside B (5), were isolated from the crude extract of the fungal strain Chaetomium elatum No. 89-1-3-1. Their structures were determined by detailed NMR and MS spectroscopic analyses. The absolute configurations of C-7 in chaetomugilin S (1), 7,5'-bis-epi-chaetoviridin A (2), and 7-epi-chaetoviridin E (3) were assigned by CD experiments, and the absolute configurations of 1 and 2 were established by X-ray crystallography. Compounds 1-3 are the first examples of 7R-configurated azaphilones with a chlorinated isochromen from Chaetomium spp. In addition, compounds 1-3 showed inhibitory activity in the cysteine aspartyl-specific protease-3 (caspase-3) enzymatic assay, with IC₅₀ values of 20.6, 10.9, and 7.9 µM, respectively.
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- 2012
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215. Preparation and characterization of enrofloxacin-imprinted monolith prepared with crowding agents
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Xiao-Xia Li, Huan Wang, Jia Wang, Li-Hong Bai, Zhao-Sheng Liu, and Yan-Ping Huang
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Acetonitriles ,Monolithic HPLC column ,Ethylene glycol dimethacrylate ,Molecular Conformation ,Biochemistry ,Analytical Chemistry ,Acetone ,Molecular Imprinting ,chemistry.chemical_compound ,Molecular recognition ,Dimethyl Sulfoxide ,Monolith ,Chromatography, High Pressure Liquid ,Enrofloxacin ,geography ,Chromatography ,geography.geographical_feature_category ,Chemistry ,Organic Chemistry ,Molecularly imprinted polymer ,General Medicine ,Polymerization ,Methacrylic acid ,Molecular imprinting ,Porosity ,Fluoroquinolones - Abstract
Molecular crowding is a new approach to promoting molecular imprinting more efficiently. In this work, this concept was applied to the preparation of imprinted monoliths in the presence of molecular crowding agent for stabilizing binding sites and improving molecular recognition. The imprinted monolithic column was synthesized using a mixture of enrofloxacin (template), methacrylic acid, ethylene glycol dimethacrylate, and polystyrene (molecular crowding agent). Some polymerization factors, such as template-monomer molar ratio and the composition of the porogen, on the imprinting effect of resulting MIP monolith were systematically investigated. Moreover, a stoichiometric displacement model for retention was successfully applied to evaluate the interaction between the solute and the stationary phase. Compared with the MIP prepared by conventional polymerization, the molecular crowding-based monolithic MIPs showed higher selectivity. The results suggested that molecular crowding is a powerful strategy to increase the effect of molecular imprinting.
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- 2012
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216. Study on the Intelligent Design System of Square Tube Aluminum Profile Extrusion Processes Based on VB
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Han Wu Liu, Xiao Xia Li, and Zhi Ping Zhang
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Parametric programming ,Engineering ,business.product_category ,business.industry ,General Engineering ,Process (computing) ,Mechanical engineering ,Forming processes ,GeneralLiterature_MISCELLANEOUS ,Finite element method ,Parametric design ,Die (manufacturing) ,Extrusion ,Tube (container) ,business - Abstract
According to the similar characteristics of structure, geometry and constraints conditions in the same type of extrusion process, the intelligent design system of a square tube aluminum profile extrusion forming process was established in this paper based on the VB programming language, with using parametric programming language APDL provides by ANSYS software. The parameterized optimization design plan of pre-treatment and post-processing of ANSYS analysis during a square tube aluminum extrusion forming process was achieved, and the program of a three-dimensional model of the extrusion die under Visual Lisp environment was also programmed. The human-computer interaction intelligent design system which combined with pre-processing of semi-finished product, finite element analysis of extrusion die strength, extrusion die temperature field analysis, structural optimization of the die was realized. The research results show that the system can provide program decision-making, structural design, performance analysis and graphics treatment for the actual extrusion productions of square tube aluminum extrusion process, which reduced the design time of the technical staff, and saved design cost.
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- 2012
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217. Polarized Infrared and Raman Spectra on Molecular Orientation of Phthalocyanine Derivatives in Nanolaminated Films
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Hai Xia Xiao, Hui Miao Guo, Xiao Xia Li, Li Fen Cao, Shi Liu, Hai Ning Cui, and Shi Quan Xi
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Materials science ,Nanostructure ,Infrared ,General Engineering ,Infrared spectroscopy ,Chromophore ,Photochemistry ,symbols.namesake ,chemistry.chemical_compound ,Crystallography ,chemistry ,Monolayer ,symbols ,Phthalocyanine ,Raman spectroscopy ,Spectroscopy - Abstract
The orientation of the hydrocarbon chains and functionally important chromophore of copper (II) phthalocyanine (CuPc) derivatives are discussed by spectrum assessment methods in ordered thin films. The attention is focused upon the monolayer and multilayer films of CuPc derivatives that are symmetrically and asymmetrically substituted CuPc biosimulation systems. On the basis of infrared (IR) transmission, polarized IR, reflection–absorption (RA) IR spectroscopy and surface enhancement resonance Raman spectra (SERRS) study, following conclusions are given. The hydrocarbon chains of CuPc in the film are in hexagonal or pseudohexagonal subcell packing, and the CH2 asymmetric vibrational vector is oriented with respect to the substrate surface. The macrocycle of CuPc on the Ag substrate is oriented parallel to the surface, and the RA spectroscopy can distinguish the two CH2 stretching modes of benzene cycle. All these studies and results are useful to provide an insight into the nanostructure of the thin films of other kinds of compounds.
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- 2012
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218. Effect of annealing on photoluminescence of blue-emitting ZnO nanoparticles by sol–gel method
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Guoping Du, Han Wang, Andy Y. M. Suen, Nan Chen, Xiao Xia Li, and Zhong Chen
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Materials science ,Photoluminescence ,Condensed Matter::Other ,Scanning electron microscope ,Annealing (metallurgy) ,Physics::Optics ,Nanoparticle ,General Chemistry ,Condensed Matter Physics ,Microstructure ,Electronic, Optical and Magnetic Materials ,Biomaterials ,Condensed Matter::Materials Science ,Crystallography ,Crystallinity ,Chemical engineering ,Materials Chemistry ,Ceramics and Composites ,Powder diffraction ,Wurtzite crystal structure - Abstract
In this work, we investigated the influence of annealing on the crystallinity, microstructures, and photoluminescence (PL) properties of ZnO nanoparticles prepared by sol–gel method. The annealing was carried out both in air and vacuum. X-ray powder diffraction, scanning electron microscopy, and ultraviolet–visible spectroscopy were used to characterize the crystal structures, diameter, surface morphology, and PL properties of ZnO nanoparticles. It has been found that both the as-grown and annealed ZnO nanoparticles had a hexagonal wurtzite crystal structure, and their average diameter and crystallinity increased with the anneal time and temperature. Pure blue-emitting behavior was observed in all samples. The emission intensity of ZnO nanoparticles was found to be enhanced after annealing, but it was highly dependent on the annealing conditions. Optimal annealing conditions both in air and vacuum were obtained for achieving maximum emission intensity in the ZnO nanoparticles. The dependence of PL properties of the ZnO nanoparticles on the annealing conditions was discussed.
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- 2012
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219. Release evaluation of molecularly imprinted polymers prepared under molecular crowding conditions
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Xiao-Xia Li, Hong-Quan Duan, Yan-Ping Huang, Zhao-Sheng Liu, and Lan‐Fang Hao
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chemistry.chemical_classification ,Materials science ,Polymers and Plastics ,Ethylene glycol dimethacrylate ,Molecularly imprinted polymer ,General Chemistry ,Polymer ,chemistry.chemical_compound ,Monomer ,chemistry ,Methacrylic acid ,Dynamic light scattering ,Polymer chemistry ,Materials Chemistry ,Precipitation polymerization ,Polystyrene - Abstract
In this work, molecular crowding agent was first applied to the preparation of molecularly imprinted polymer (MIP)-based drug release system. With S-naproxen as template, the MIPs were prepared with methacrylic acid and ethylene glycol dimethacrylate, in the presence of polystyrene as molecular crowding by precipitation polymerization. Morphology and particle size of the resulting MIP sub-micrometer microparticles were determined by scanning electron microcopy and dynamic light scattering. The influence of several parameters on the sustained release of the imprinted polymers was investigated, including the molar ratio of the imprint molecule to the functional monomers, the molar ratio of the functional monomers to the crosslinking monomers, and the type of the porogen. In addition, the release of the MIP was compared to that of the traditionally prepared imprinted polymers with other porogens. The transport mechanism of template was studied by fitting experiment data with different model equations and calculating the corresponding parameters. The novel MIPs prepared with molecular crowding were able to prolong S-naproxen, in a phosphate buffers solution of pH 7.4, for more than 12 h, indicating better sustained release effect than that prepared with noncrowding agent. POLYM. ENG. SCI., 2012. © 2012 Society of Plastics Engineers
- Published
- 2012
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220. Formation of Mesophase Spheres in a QI-Free Coal Tar Pitch
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Xue Fei Zhao, Li Yue, Shi Quan Lai, and Xiao Xia Li
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Materials science ,Yield (engineering) ,Extraction (chemistry) ,Thermal ,Isotropy ,General Engineering ,medicine ,Mesophase ,SPHERES ,Radius ,Coal tar ,Composite material ,medicine.drug - Abstract
A QI-free coal tar pitch prepared by solvent extraction from a soft coal tar pitch was subjected to a series of thermal treatments at a predetermined temperature for different holding times. The development of mesophase was discussed in terms of its size and content in the heat-treated pitches. Results showed that the size and yield of the dispersed mesophase spheres in the isotropic matrix strongly depended on the holding temperatures. When the holding temperature was less than 400 °C, only a few of small spheres formed in the mesophase pitches. However, when the holding temperature was over 420 °C, the diameter and yield of mesophase spheres in the heat-treatment pitches increased progressively with increase of the holding time. Treatment at 440 °C for 4h led to 19.9 % of the yield and the average sphere radius was 4.5-100 . In the SEM photograph of mesocarbon microbeads obtained from the heat-treated pitches using soxhlet extraction. Many small flaky particles and sporadic rugby ball-shaped particles were observed as well as a large number of spherical particles.
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- 2012
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221. Study on the optical properties of Zn1−xMgxS (0≤x≤0.55) quantum dots prepared by precipitation method
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Nan Chen, Xiao Xia Li, Yangsheng Li, Guihua Liu, Guoping Du, Zhong Chen, and Andy Y.M. Suen
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Photoluminescence ,Materials science ,Band gap ,Scanning electron microscope ,Mechanical Engineering ,Doping ,Crystal structure ,Condensed Matter Physics ,Microstructure ,Crystallography ,Mechanics of Materials ,Quantum dot ,General Materials Science ,Crystallite - Abstract
Zn 1− x Mg x S (0 ≤ x ≤ 0.55) quantum dots (QDs) were successfully synthesized by precipitation method. The crystal structures, microstructures, and optical properties of the Zn 1− x Mg x S QDs were investigated using X-ray diffraction, scanning electron microscopy, and ultraviolet-visible and photoluminescence (PL) spectroscopy. The Zn 1− x Mg x S QDs were found to have a cubic crystal structure and an average crystallite size of 6.40–7.96 nm. It has been shown that an increase in doping Mg 2+ concentration in Zn 1− x Mg x S QDs led to a gradual widening of the band gap and a weakening in the PL intensity of the Zn 1− x Mg x S QDs.
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- 2012
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222. Experimental Study on Behaviour of RC Column Confined by CFRP and Steel Fibre
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Xiao Xia Li
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First specimen ,Materials science ,Column (typography) ,business.industry ,Steel fibre ,General Engineering ,Structural engineering ,Composite material ,Fibre-reinforced plastic ,Reinforced concrete ,Ductility ,business ,Rc columns - Abstract
12 RC columns specimens are divided 4 groups which have different eccentricities. Each group has 4 specimens, The first specimen was just made of reinforced concrete. The second was wrapped with 3 lays CFRP. The third had steel fibres added to it. The last was reinforced with steel fibres and wrapped with CFRP.The results showed that the introduction of fibres as well as wrapping the specimens with FRP improve the strength of concrete,especially its ductility.
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- 2012
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223. Forming Shape of Narrow Groove Machined by Electro Jet Machining
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Fu Yuan Li, Xiao Xia Li, and Qiao Lin Zhang
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Engineering ,Three dimensional shape ,Jet (fluid) ,Optics ,Machining ,business.industry ,Design of experiments ,General Engineering ,Process (computing) ,business ,Ellipse ,Groove width ,Groove (engineering) - Abstract
In order to study small size three dimensional shape processing of electro jet machining, the micro-channel principle is introduced firstly. Moreover, narrow groove processing experiment design and construction process is described, and experimental purpose is to change the cycle times to research the rule of groove width and depth. The experimental results indicate that when the width of the groove reaches a certain value, it will be stabilized and fluctuate around the value. However, with the increasing of the cycle number, groove depth increases. If cycle times are less than 7, the overall shape of the groove is a part of an approximate ellipse, otherwise it is changed but the bottom shape of the groove is still a part of an approximate ellipse.
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- 2011
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224. The Investigation on the Abrasive Jet to Change the Contact Angle of Solid Material Surface
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Pu Liu, Qiao Ling Zhang, Xiao Xia Li, and Fu Yuan Li
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Surface (mathematics) ,Contact angle ,Jet (fluid) ,Morphology (linguistics) ,Materials science ,chemistry ,Abrasive ,General Engineering ,chemistry.chemical_element ,Solid material ,Composite material ,Processing methods ,Titanium - Abstract
In order to change surface morphology and contact angle of part, abrasive jet method is discussed in the paper. Glass, steel and titanium are used to study its surface morphology by the processing of abrasive to jet the surface. In addition, the extent of its impact of processing method is studied with different abrasive size. Experiment method and environment are also introduced, and experiment shows that contact angle of glass changes from 14.9° to 93.8° (Titanium and steel also have different degrees of diversification). According to experiment of the method, abrasive jet methods affects contact angle, and it has the value of further research.
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- 2011
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225. Experiment of Temperature Field for High Speed Orthogonal Turning
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Mu Lan Wang, Xiao Xia Li, Yong Feng, and Bao Sheng Wang
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Maximum temperature ,Engineering ,Experimental system ,Field (physics) ,Thermocouple ,business.industry ,Model simulation ,Experimental data ,Mechanical engineering ,General Medicine ,business ,Temperature measurement ,Finite element method - Abstract
An experimental system used for temperature measurement is designed by the K-type thermocouple thermometry to achieve a direct measurement of cutting temperature in high speed orthogonal turning. The general regularity of temperature distribution is concluded, and the corresponding influences of cutting speed and cutting depth on the maximum temperature value are discussed in detail. Experimental data and simulating results are comparative analyzed to demonstrate the feasibility and correctness of Finite Element Method (FEM) model simulation and analytical solution. The verified model of temperature field can be applied to develop an effective non-contact soft-sensing method for high speed cutting temperature.
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- 2011
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226. A sol–gel method for preparing ZnO quantum dots with strong blue emission
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Andy Y.M. Suen, Nan Chen, Zhong Chen, Xiao Xia Li, and Guoping Du
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Materials science ,Photoluminescence ,Scanning electron microscope ,Annealing (metallurgy) ,Biophysics ,Analytical chemistry ,General Chemistry ,Condensed Matter Physics ,Biochemistry ,Atomic and Molecular Physics, and Optics ,Crystallography ,Quantum dot ,Luminescence ,Spectroscopy ,Diffractometer ,Wurtzite crystal structure - Abstract
ZnO quantum dots (QDs) with strong blue emission have been successfully synthesized by sol–gel method, and their crystal structures, sizes, and photoluminescence properties were characterized by X-ray diffractometer, scanning electron microscope, and ultraviolet–visible spectroscopy. It has been found that ZnO QDs had a hexagonal wurtzite crystal structure, and their average diameter was about 16.0–32.2 nm. Both the reaction time and temperature were found to have a strong influence on the average size and photoluminescence properties of ZnO QDs. Longer reaction time and higher reaction temperature resulted in larger average size for ZnO QDs. It has been shown that at reaction temperature 60 °C the emission intensity for ZnO QDs increased first with reaction time before 7 h and then decreased after 7 h. For the same reaction time 7 h, ZnO QDs synthesized at 60 °C showed the strongest emission intensity. It was found that annealing in nitrogen, vacuum, and air all resulted in an increase of the size of ZnO QDs and a reduction in their photoluminescence. The dependence of the size and properties of ZnO QDs on the reaction parameters as well as the annealing conditions has been discussed.
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- 2011
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227. Flood Disasters and the Development of Early Warning Model for Railway
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Xiang-ning Guan, You-sheng Wang, Jian-rui Quan, Xiao-xia Li, and Yong Wang
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Atmospheric Science ,History ,Ecology ,Flood myth ,Early warning model ,Forensic engineering ,Geology ,Environmental Science (miscellaneous) ,Water Science and Technology - Published
- 2011
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228. Preparation of imprinted monolithic column under molecular crowding conditions
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Yan-Ping Huang, Li Hong Bai, Xiao Xia Li, Hong-Quan Duan, Xin Liu, and Zhao-Sheng Liu
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Monolithic HPLC column ,genetic structures ,Molecularly imprinted polymer ,Nanotechnology ,General Chemistry ,Crowding ,chemistry.chemical_compound ,Molecular recognition ,chemistry ,Polymerization ,Chemical engineering ,Polystyrene ,Selectivity ,Tetrahydrofuran - Abstract
Molecular crowding is a new concept to obtain molecularly imprinted polymers (MIPs) with greater capacity and selectivity. In this work, molecular crowding agent was firstly applied to the preparation of MIPs monolithic column. A new polymerization system based on molecular crowding surrounding was developed to prepare enrofloxacin-imprinted monolith, which was composed of polystyrene and tetrahydrofuran. The result showed that the monolithic MIPs under molecular crowding conditions presented good molecular recognition for enrofloxacin with an imprinting factor of 3.03.
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- 2011
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229. Recognition of splice sites based on fuzzy support vector machine
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Bo Sun, Cheng-guo Li, and Xiao-xia Li
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Fuzzy support vector machine ,Computer science ,business.industry ,splice ,Pattern recognition ,Artificial intelligence ,Machine learning ,computer.software_genre ,business ,computer - Published
- 2011
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230. When interspecific prezygotic barriers break down: hybridization between two Potamogeton species (P. wrightii and P. perfoliatus) and comparison of the artificial and natural hybrids
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You-Hao Guo, Xiao-Xia Li, Le-Yi Ni, and Xiao-lin Zhang
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biology ,media_common.quotation_subject ,Plant Science ,Interspecific competition ,biology.organism_classification ,Plant ecology ,Speciation ,Germination ,Backcrossing ,Botany ,Pollen tube ,Potamogeton ,Ecology, Evolution, Behavior and Systematics ,media_common ,Hybrid - Abstract
Interspecific hybridization played an important role in speciation and evolution of angiosperms. Although the widespread occurrence of natural hybrids in the genus Potamogeton has been studied intensively, few successful experimental hybridization studies have been reported in this genus. In the present study, critical experimental hybridization was conducted using Potamogeton x intortusifolius, a natural hybrid widely distributed in China, and its parents (P. perfoliatus and P. wrightii). The absence of prezygotic barriers between P. wrightii and P. perfoliatus was observed, which contributes to the frequent hybridization of these species in nature. The pollen tube growth rates of P. perfoliatus were much faster than those of P. wrightii in the style of that species. However, the conspecific pollen tubes were competitively advantageous in P. perfoliatus styles. The interspecific hybridization could be applied bidirectionally, and 28 F1 hybrid individuals were successfully obtained from P. wrightii x P. perfoliatus, despite the low germination possibility of the hybrid seeds. Both the artificial and natural hybrids exhibited intermediate morphological characters but presented much lower fertility. The sterility of P. x intortusifolius is mainly due to its low female fitness. However, the offspring from P. wrightii x P. x intortusifolius indicated the potential for backcrossing in nature. This is the most successful attempt at artificial hybridization in this genus so far. The possible route for restoration of fertility and the fitness of the hybrids are also discussed in this paper.
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- 2011
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231. Detection of Impact Damages in CFRP Composites Using Ultrasonic Burst Phase Thermography
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Zheng Zhang, Nai Ming Wu, Cun Lin Zhang, Dapeng Chen, Xiao Xia Li, and Yue Li
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Carbon fiber reinforced polymer ,Damage detection ,Materials science ,business.industry ,Mechanical Engineering ,Structural engineering ,Condensed Matter Physics ,Imaging Tool ,Mechanics of Materials ,Nondestructive testing ,Thermography ,Impact energy ,General Materials Science ,Ultrasonic sensor ,Composite material ,business ,Pulse thermography - Abstract
Carbon fiber reinforced polymer (CFRP) composites have been used extensively because of their excellent performance, but they are susceptible to the impact damages, such as the impact of birds, runway stones and tools off can cause the failure of CFRP composites. Therefore, nondestructive testing of CFRP composites is necessary to promote the failure control and prevention. Ultrasonic burst phase thermography (UBP) developed a few years ago is a defect-selective and fast imaging tool for damage detection. This paper describes the principle of UBP, gives some UBP testing results of impact damages in five CFRP laminated boards. The shape and position of the damages are shown in the phase images visualized and the relationship between the damage areas and impact energy is discussed. The flash pulse thermography (PT) results and ultrasonic C-scan results are also shown as comparison. It is concluded that all of the three NDT methods have their own characteristics and the comparison verifies the feasibility of CFRP impact damage detection using ultrasonic burst phase thermography.
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- 2011
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232. Infrared Thermal Wave Quantitative Evaluation for Fiber Reinforced Composites
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Xiao Xia Li, Dapeng Chen, Shi Bin Zhao, Nai Ming Wu, and Na Cai
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Materials science ,Infrared ,business.industry ,Mechanical Engineering ,Composite number ,Glass fiber ,Image processing ,Fiber-reinforced composite ,Mathematical morphology ,Condensed Matter Physics ,Pulse (physics) ,Optics ,Mechanics of Materials ,General Materials Science ,Thermal wave ,business - Abstract
Infrared thermal wave testing is a non-contact inspection technique that maps the surface temperature of an object after some energy is applied to it. The mechanism of pulsed infrared thermal wave testing was analyzed in detail. Glass fiber reinforced composite was tested by infrared thermal wave testing. Some intensive research on quantitative defect evaluation was developed. Through analysis of the temperature-time curve of two points over a suspected defective location and over a sound area on material surface, the change rule of temperature difference was found. It provided a basis for depth quantitative evaluation. According to the peculiarity of infrared image, an image enhancement approach based on mathematical morphology was adopted, which solve the problem of poor contrast and low signal-to-noise ratio caused by pulse heating. And an image processing program was developed to extract the size information of defects.
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- 2011
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233. Design of Free-Form Surface Optic in Wide Field of View Off-Axis Optical System
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You Long, Xiao Xia Li, and Ming Wu Kang
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Surface (mathematics) ,Engineering ,Image quality ,business.industry ,Design specification ,ComputingMethodologies_IMAGEPROCESSINGANDCOMPUTERVISION ,General Medicine ,Wide field ,law.invention ,Lens (optics) ,Optics ,law ,Electronic engineering ,Systems design ,Off-axis optical system ,Free form ,business - Abstract
Design of off-axis system is a hot and difficult topic in optical design area. The wide field of view(WFOV) off-axis system this paper involved always have the drawbacks of complicated large size and great weight. This paper introduces an application of free-form surface(FFS) in WFOV off-axis optical system design, analyzes FFS optics’ material and fabrication methods. The system uses one FFS lens and one doublet, image quality meets the design specification, and characterizes by simple structure and lightweight.
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- 2011
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234. Fabrication of Beltlike Fibers by Electrospinning
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He Chunhui, Liu Yanqing, Ji-Huan He, and Xiao-Xia Li
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two-dimensional material ,Materials science ,Fabrication ,molecule junction ,Polymers and Plastics ,020209 energy ,surfactants and dispersing agents ,Physics::Optics ,Nanoparticle ,02 engineering and technology ,Article ,Taylor cone ,lcsh:QD241-441 ,Surface tension ,lcsh:Organic chemistry ,0202 electrical engineering, electronic engineering, information engineering ,Composite material ,Spinning ,Computer Science::Databases ,nanoparticle ,graphene ,dropping process ,General Chemistry ,Electrospinning ,Nanofiber ,Crystallite ,mathematical model - Abstract
Electrospinning is always used to fabricate one-dimensional nanofibers. Cylindrical fibers are formed during the spinning process due to the minimal-surface principle. However, when the moving jet has high rigidity, which can counteract the surface tension for a minimal surface, beltlike fibers can be obtained. Using the Hall&ndash, Petch effect, the rigidity of the moving jet can be greatly enhanced by adding nanoparticles. Polyethylene glycol with a nanometric crystallite size of 4 nm and ZrO2 nanoparticles are used as additives in the experiment, a theoretical analysis is carried out, and the theoretical predictions are verified experimentally.
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- 2018
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235. Selective Early Glial Reactivity in the Visual Pathway Precedes Axonal Loss, Following Short-Term Cerebrospinal Fluid Pressure Reduction
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Xiao Xia Li, Lu Liu, Di Ya Yang, Zheng Zhang, Qian Liu, Shen Wu, Ningli Wang, Hui Yang Zeng, and Jing Xue Zhang
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Male ,Retinal Ganglion Cells ,Superior Colliculi ,medicine.medical_specialty ,genetic structures ,Blotting, Western ,Optic Disk ,Axonal loss ,Lateral geniculate nucleus ,Rats, Sprague-Dawley ,03 medical and health sciences ,0302 clinical medicine ,Microscopy, Electron, Transmission ,Cerebrospinal Fluid Pressure ,Glutamate-Ammonia Ligase ,Internal medicine ,Glial Fibrillary Acidic Protein ,Optic Nerve Diseases ,medicine ,Animals ,Visual Pathways ,Fluorescent Antibody Technique, Indirect ,Intraocular Pressure ,Retina ,Glial fibrillary acidic protein ,biology ,Chemistry ,Superior colliculus ,Geniculate Bodies ,Axons ,eye diseases ,Rats ,medicine.anatomical_structure ,Endocrinology ,nervous system ,Retinal ganglion cell ,030221 ophthalmology & optometry ,biology.protein ,Optic nerve ,sense organs ,Cerebrospinal fluid pressure ,Neuroglia ,030217 neurology & neurosurgery - Abstract
Purpose To examine the early glial reactivity and neuron damage in response to short-term cerebrospinal fluid pressure (CSFp) reduction, as compared with intraocular pressure (IOP) elevation. Methods The experiment included 54 male Sprague-Dawley rats with elevated translaminar cribrosa pressure difference (TLPD), defined as IOP minus CSFp. These rats underwent either continuous CSF drainage for 6 hours (n = 18), or unilateral IOP elevation to 40 mm Hg for 6 hours (n = 18). For control, 18 normal rats were anesthetized for 6 hours. Orthograde axonal transport was examined by intravitreal injection of 3% rhodamine-β-isothiocyanate. We also used transmission electron microscopy to display the ultrastructural features of retinal ganglion cell axons in the optic nerve head. Early glial reactivity in the retina, lateral geniculate nucleus (LGN), and superior colliculus (SC) was detected by immunostaining and Western blot for the glial fibrillary acidic protein (GFAP) and glutamine synthetase (GS). We also observed the glial reactivity in the inferior colliculus and hippocampus to rule out possible influences of CSF dynamics and composition. Results Anterograde staining with 3% rhodamine-β-isothiocyanate revealed decreased fluorescence intensity of the SC and LGN projected from both lower CSFp and higher IOP eyes. Transmission electron microscopy showed loss of axons from the optic nerve head in the high-IOP group, but not in the low-CSFp group. Compared with the anesthesia control group, GFAP expression was significantly increased in the retina, LGN, and SC, whereas GS expression was only increased in the retina following CSFp reduction. However, their expressions were not significantly elevated in the inferior colliculus and hippocampus. In the high-IOP group, expressions of GFAP and GS were significantly increased in the retina, LGN, and SC. Conclusions Visual system neurons may be much more sensitive than other nervous tissues. Following short-term CSFp reduction, early glial reactivity may precede axonal loss. Changes of translaminar cribrosa pressure difference in both experimental low-CSFp and high-IOP groups induce selective early glial reactivity. The neuron damage from abnormally low CSFp may be pathogenetically similar to high IOP.
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- 2018
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236. Dependence of domain wall structures on repetition n in [Pt(0.5 nm)/Co(0.4 nm)] n /NiO(1.1 nm)/[Co(0.4 nm)/Pt(0.5 nm)] n multilayers
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Xiao-xia Li and Gang Han
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Materials science ,Condensed matter physics ,Magnetometer ,Mechanical Engineering ,Non-blocking I/O ,Metals and Alloys ,Analytical chemistry ,law.invention ,Coupling (electronics) ,Condensed Matter::Materials Science ,Domain wall (magnetism) ,Ferromagnetism ,Geochemistry and Petrology ,Mechanics of Materials ,law ,Materials Chemistry ,Antiferromagnetism ,Condensed Matter::Strongly Correlated Electrons ,Perpendicular anisotropy ,Magnetic force microscope - Abstract
The magnetic force microscopy and a sample vibrating magnetometer have been used to investigate the domain structure in two antiferromagnetically coupled Co/Pt multilayers. In the antiferromagnetic coupled [Pt(0.5 nm)/Co(0.4 nm)] n /NiO(1.1 nm)/[Co(0.4 nm)/Pt(0.5 nm)] n multilayers with perpendicular anisotropy, the antiferromagnetic interlayer coupling strength increases linearly with the repetition number n in Co/Pt multilayers. In demagnetized states, relatively shifted domain walls in the two Co/Pt multilayers are observed, with net ferromagnetic stripes formed between them for the repetition number n less than 5, and the stripe width decreases with the increase of n. The occurrence of these features can be attributed to the competition between the interlayer coupling and magnetostatic energies.
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- 2010
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237. What can we learn from the presence of anti-cyclic citrullinated peptide antibodies in systemic lupus erythematosus?
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Lin Li, Chun Li, Xiao-xia Li, Zhanguo Li, Jing Li, and Yi Zhao
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Adult ,musculoskeletal diseases ,China ,medicine.medical_specialty ,Adolescent ,Anti-nuclear antibody ,Arthritis ,Peptides, Cyclic ,Gastroenterology ,Arthritis, Rheumatoid ,Diagnosis, Differential ,Young Adult ,Rheumatology ,Reference Values ,immune system diseases ,Internal medicine ,medicine ,Humans ,Lupus Erythematosus, Systemic ,Clinical significance ,Young adult ,skin and connective tissue diseases ,Aged ,Autoantibodies ,Aged, 80 and over ,Lupus erythematosus ,biology ,business.industry ,Middle Aged ,medicine.disease ,Anti-cyclic citrullinated peptide ,Rheumatoid arthritis ,biology.protein ,Antibody ,business - Abstract
Anti-cyclic citrullinated peptide (anti-CCP) antibodies have proved to be a specific marker for the diagnosis of rheumatoid arthritis (RA). However, the antibodies can also be detected in other rheumatic diseases, especially systemic lupus erythematosus (SLE). Recent studies have shown anti-CCP antibodies are associated with erosive arthritis in SLE patients. Since erosive arthritis is not common in SLE and many patients with non-erosive arthritis also have anti-CCP antibodies, the clinical significance of anti-CCP antibodies in SLE needs to be further studied.To investigate the prevalence and clinical significance of anti-CCP antibodies in Chinese SLE patients.Serum samples from 138 SLE patients were examined for anti-CCP with the second generation anti-CCP detection kit. The associations of anti-CCP with clinical and laboratory features, especially arthritis, in such SLE patients were analyzed.The prevalence of anti-CCP was 13.8% (19/138) in Chinese SLE patients. Seventy of 138 SLE patients had experienced arthritis, of whom 14 patients were anti-CCP+. Significantly, anti-CCP antibodies were more frequently found in SLE patients with arthritis than without arthritis (20% vs 7.4%, P0.05). A statistical correlation between anti-CCP and rheumatoid factor (RF) was found in SLE patients with arthritis (r=0.36, P=0.002). The frequency of arthritis was significantly higher in SLE patients with anti-CCP than without (73.7% vs 47.1%,P0.05). Eight out of 138 SLE patients showed joint erosions on radiographs. When compared with anti-CCP- patients, erosive arthritis occurred more often in anti-CCP+ patients (35.7% vs 5.4%, P0.001). Interestingly, two patients without anti-CCP and RF who had erosive arthritis were anti-RA33 antibodies positive. All of 8 SLE patients with erosive arthritis in our study fulfilled 1987 ACR criteria for RA. With regard to other clinical and laboratory features, there were no differences between SLE patients with arthritis and without or between anti-CCP+ patients and anti-CCP- patients.Anti-CCP antibodies have a frequency of 13.8% in Chinese SLE patients and its presence is closely associated with the onset of arthritis and bone erosion.
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- 2009
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238. Anticorps anti-peptides cycliques citrullinés dans le lupus érythémateux systémique
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Xiao-xia Li, Lin Li, Yi Zhao, Jing Li, Chun Li, and Zhanguo Li
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Gynecology ,medicine.medical_specialty ,Rheumatology ,business.industry ,medicine ,medicine.disease ,business ,Connective tissue disease - Abstract
Resume Contexte Les anticorps anti-peptides cycliques citrullines (ACCP) sont des marqueurs specifiques reconnus dans le diagnostic de polyarthrite rhumatoide (PR). Cependant, ces anticorps peuvent egalement etre detectes dans d’autres maladies rhumatologiques, notamment dans le lupus erythemateux systemique (LES). Des etudes recentes ont montre que les ACCP sont associes a une polyarthrite erosive chez les patients atteints de lupus. La signification clinique des ces anti-CCP dans le LES necessite d’etre etudiee de maniere plus approfondie dans la mesure ou la polyarthrite erosive n’est pas observee frequemment dans le LES et que beaucoup de patients avec une polyarthrite non erosive sont egalement ACCP+. Objectif Rechercher la prevalence et la signification clinique des anticorps anti-CCP chez des patients chinois atteints de LES. Methodes Les anti-CCP ont ete recherches avec la deuxieme generation de test de depistage a partir des serums de 138 patients atteints de LES. L’association entre les anti-CCP et les signes biologiques et cliniques, notamment la polyarthrite, a ete analysee chez ces patients. Resultats La prevalence des anti-CCP etait de 13,8 % (19/138) chez les patients chinois atteints de LES. Soixante-dix des 138 patients avaient une polyarthrite, dont 14 etaient anti-CCP+. Les ACCP etaient retrouves plus frequemment et de maniere significative chez les patients qui presentaient une polyarthrite, que chez les patients sans polyarthrite (20 % versus 7,4 %, p r = 0,36, p = 0,002). La frequence de la polyarthrite etait significativement plus elevee chez les patients avec anti-CCP que sans anti-CCP (73,7 % versus 47,1 %, p p Conclusion Les ACCP etaient positifs chez 13,8 % des patients chinois atteints de LES ; leur presence est etroitement associee a une polyarthrite debutante et a une erosion osseuse.
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- 2009
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239. Levels of the potential biomarker p11 in peripheral blood cells distinguish patients with PTSD from those with other major psychiatric disorders
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Maree J. Webster, Dragan Maric, He Li, Tung Ping Su, Robert J. Ursano, David M. Benedek, Lei Zhang, Ming Yi Chung, Xiao Xia Li, Yuan-Hwa Chou, Jeffery L. Barker, Janis Carlton, Ying Sheue Chen, Ya Mei Bi, and James E. Barrett
- Subjects
Adult ,Male ,medicine.medical_specialty ,Bipolar Disorder ,Time Factors ,Hydrocortisone ,Radioimmunoassay ,behavioral disciplines and activities ,Life Change Events ,Stress Disorders, Post-Traumatic ,Receptors, Glucocorticoid ,mental disorders ,Hamd ,medicine ,Humans ,HARS ,RNA, Messenger ,Bipolar disorder ,Saliva ,Psychiatry ,Annexin A2 ,Biological Psychiatry ,Psychiatric Status Rating Scales ,Analysis of Variance ,Depressive Disorder, Major ,Trauma Severity Indices ,Hamilton Rating Scale for Depression ,Middle Aged ,medicine.disease ,Psychiatry and Mental health ,Schizophrenia ,Leukocytes, Mononuclear ,Anxiety ,Major depressive disorder ,Female ,medicine.symptom ,Psychology ,Anxiety disorder - Abstract
Posttraumatic stress disorder (PTSD) is a severely debilitating anxiety disorder. Over 80% of patients with PTSD also exhibit other psychiatric condition, such as bipolar disorder (BP) or major depression (MDD). Previously, it has been found that p11 mRNA expression was significantly changed in post mortem cortex of patients with PTSD and depression. We hypothesize that p11 mRNA levels in the peripheral blood cells will be a potential biomarker for PTSD with heterogeneity in terms of type of trauma, time since trauma and duration of illness. We examined the peripheral blood mononuclear cell (PBMC) P11 mRNA of patients with PTSD (n=13), major depressive disorder (MDD, n=16), bipolar disorder (BP, n=24), and schizophrenia (SCZ, n=12) or controls (n=14) using quantitative real-time PCR and the circulating levels of cortisol in blood plasma and saliva of PTSD using radioimmunoassay kit CORT-CT2. The Hamilton Rating Scale for Depression (HAMD) and Anxiety (HARS), the Chinese version of the Davidson Trauma Scale-Frequency (CDTS-F) and the Chinese version of the Davidson Trauma Scale-Severity (CDTS-S), and Impact of Event Scale-Revised (IES-R) were administered. We found that patients with PTSD had lower levels of p11 mRNA than control subjects, while those with MDD, BP and SCZ had significantly higher p11 levels than the controls. P11 mRNA levels were positively correlated with the scores of HAMD (r=0.62, p
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- 2009
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240. Effects of Si4+ and B3+ doping on the photoluminescence of BaMgAl10O17:Eu2+ phosphor under UV and VUV excitation
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Xiao Xia Li, Zhan Hui Zhang, and Yu Hua Wang
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Materials science ,Photoluminescence ,Mechanical Engineering ,Spinel ,Inorganic chemistry ,Doping ,Metals and Alloys ,Analytical chemistry ,Phosphor ,engineering.material ,medicine.disease_cause ,Crystallographic defect ,Mechanics of Materials ,Materials Chemistry ,engineering ,medicine ,Thermal stability ,Luminescence ,Ultraviolet - Abstract
Si 4+ and B 3+ were doped into the spinel block of blue-emitting BaMgAl 10 O 17 :Eu 2+ phosphor. Their photoluminescence, such as emission characteristic and thermal stability, were investigated under ultraviolet (UV) and vacuum ultraviolet (VUV) excitation. The results showed that proper quantities of Si 4+ or B 3+ doping could obviously improve the emission intensity. However, the thermal stability of Si 4+ or B 3+ doped phosphors was worse than that of undoped samples. Based on lattice defect theory, the mechanisms of these interesting phenomena were discussed and explained, which revealed that the thermal degradation of BaMgAl 10 O 17 :Eu 2+ had great correlation with the lattice environment.
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- 2009
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241. The role of the velocity gradient in laminar convective heat transfer through a tube with a uniform wall heat flux
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Xiao-Xia Li, Qiang Zhang, and Liang-Bi Wang
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Physics::Fluid Dynamics ,Convection ,Physics ,Convective heat transfer ,Heat flux ,Critical heat flux ,Heat transfer ,General Physics and Astronomy ,Thermodynamics ,Heat transfer coefficient ,Mechanics ,Churchill–Bernstein equation ,Fin (extended surface) - Abstract
This paper aims to contribute to a better understanding of convective heat transfer. For this purpose, the reason why thermal diffusivity should be placed before the Laplacian operator of the heat flux, and the role of the velocity gradient in convective heat transfer are analysed. The background to these analyses is that, when the energy conservation equation of convective heat transfer is used to explain convective heat transfer there are two points that are difficult for teachers to explain and for undergraduates to understand: thermal diffusivity is placed before the Laplacian operator of temperature; on the wall surface (the fluid side) the velocity is zero, a diffusion equation of temperature is gained from energy conservation equation, however, temperature cannot be transported. Consequently, the real physical meaning of thermal diffusivity is not clearly reflected in the energy conservation equation, and whether heat transfer occurs through a diffusion process or a convection process on the wall surface is not clear. Through a simple convective heat transfer case: laminar convective heat transfer in a tube with a uniform wall heat flux on the tube wall, this paper explains these points more clearly. The results declare that it is easier for teachers to explain and for undergraduates to understand these points when a description of heat transfer in terms of the heat flux is used. In this description, thermal diffusivity is placed before the Laplacian operator of the heat flux; the role of the velocity gradient in convective heat transfer appears, on the wall surface, the fact whether heat transfer occurs through a diffusion process or a convection process can be explained and understood easily. The results are not only essential for teachers to improve the efficiency of university-level physics education regarding heat transfer, but they also enrich the theories for understanding heat transfer.
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- 2009
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242. The influence of Y3+, Sc3+ and Bi3+ on the photoluminescence of GdAl3(BO3)4:Eu3+ under UV and VUV excitation
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Xiao Xia Li, Zhong Chen, and Yu Hua Wang
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Photoluminescence ,Chemistry ,Mechanical Engineering ,Doping ,Metals and Alloys ,Analytical chemistry ,Phosphor ,medicine.disease_cause ,Emission intensity ,Mechanics of Materials ,Materials Chemistry ,medicine ,Chromaticity ,Luminescence ,Ultraviolet ,Excitation - Abstract
Single phase of Gd0.9Eu0.1Al3(BO3)(4) and Gd0.9Eu0.1Al3(BO3)(4):Re3+ (Re =Y, Sc and Bi) powder samples was prepared by the solid-state reaction and their luminescence properties were investigated under ultraviolet and vacuum ultraviolet excitation. Under 254 nm excitation, the emission intensity of Eu3+ increased after Y3+, SC3+ or Bi3+ replacing part Gd3+ of Gd0.9Eu0.1Al3(BO3)(4). Under 147 nm excitation, when substituting part Gd3+ With Sc3+ or Bi3+, the emission intensity of Eu3+ decreased, but increased after doping appropriate Y3+ and the maximum emission intensity was obtained at the concentration of x=0.6 in Gd0.9-xYxEu0.1Al3(BO3)(4). Compared with the red commercial phosphor (Y,Gd)BO3:Eu3+, the optimum phosphor Gd0.3Y0.6Eu0.1Al3(BO3)(4) exhibited about 92% the integrated emission intensity with chromaticity coordinates of (0.66, 0.33) under 147 nm excitation. (C) 2008 Elsevier B.V. All rights reserved.
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- 2009
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243. Preparation and microwave-infrared absorption of reduced graphene oxide/Cu–Ni ferrite/Al2O3 composites
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De-yue, Ma, primary, Xiao-xia, Li, additional, Yu-xiang, Guo, additional, and Yu-run, Zeng, additional
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- 2018
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244. Multipotency of human neural stem cells from fetal striatum
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Jinchong Xu, Yang Li, Xiao Xia Li, and Xiao Chun Chi
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Male ,Microinjections ,Cellular differentiation ,Transplantation, Heterologous ,Biology ,Osteocytes ,Polymerase Chain Reaction ,Mice ,Fetus ,Pregnancy ,Neurosphere ,Adipocytes ,Animals ,Humans ,Cells, Cultured ,Stem cell transplantation for articular cartilage repair ,Neurons ,Mice, Inbred ICR ,Multipotent Stem Cells ,General Neuroscience ,Cell Differentiation ,Hematopoietic Stem Cells ,Corpus Striatum ,Neural stem cell ,Cell biology ,Neuroepithelial cell ,Blotting, Southern ,Oligodendroglia ,Blastocyst ,Astrocytes ,Amniotic epithelial cells ,Female ,Myogenin ,Stem cell ,Neuroscience ,Stem Cell Transplantation ,Adult stem cell - Abstract
We had reported that neural stem cells from human fetal striatum (hsNSCs) expressed neural stem cell markers, and were capable of differentiation into neurons, astrocytes, and oligodendrocytes in vitro. To examine multipotency of hsNSCs, some experiments of transgerm layer differentiation in vitro were carried out. Our data indicated that hsNSCs could also generate osteocytes, adipocytes, and hepatocyte-like cells in vitro. Meanwhile, we injected hsNSCs into murine blastocysts at embryonic day 3.5 of gestation. Microinjection of hsNSCs led to the generation of chimeric embryos. Embryos at embryonic day 3.5 of gestation were shown to contribute to the hsNSC-derived cells by PCR-southern blot of 17alphamod, a special method to discover human cells from animals. Analysis of the donor distribution in different tissues showed that donor-derived cells seeded to various tissues. The cellular nature of the human donor cells in chimeric tissues is, however, currently unknown, and further work will be done to identify what differentiated phenotypes have developed from the human cells.
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- 2008
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245. Oscillatory antiferromagnetic interlayer coupling in Co/Pt multilayer with perpendicular anisotropy
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Liying Lu, Xiao-Xia Li, Jin Bao, Xiaoguang Xu, and Yong Jiang
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RKKY interaction ,Condensed matter physics ,Chemistry ,Oscillation ,chemistry.chemical_element ,General Chemistry ,Condensed Matter::Mesoscopic Systems and Quantum Hall Effect ,Condensed Matter Physics ,Coupling (electronics) ,Condensed Matter::Materials Science ,Ferromagnetism ,Transition metal ,Materials Chemistry ,Antiferromagnetism ,Condensed Matter::Strongly Correlated Electrons ,Platinum ,Cobalt - Abstract
Investigations have been performed on the interlayer coupling between Co layers across the Pt spacer in the sample structure of Co(4 A)/Pt(tPt A)/[Co(4 A)/Pt(6 A)]2 with perpendicular anisotropy. Below t Pt = 22 A , ferromagnetic interlayer coupling has been always observed, and above t Pt = 22 A , oscillatory antiferromagnetic interlayer coupling superimposed onto an average decay has been observed as a function of the Pt spacer thickness. The oscillatory behavior can be considered to originate from the RKKY-type coupling.
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- 2008
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246. Paclitaxel suppresses collagen-induced arthritis: a reevaluation
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Yi, Zhao, Zhi-Fang, Chang, Ru, Li, Zhan-Guo, Li, Xiao-Xia, Li, and Lin, Li
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musculoskeletal diseases ,Original Article - Abstract
Objective: To reevaluate the suppressive effect of paclitaxel (PTX) liposome on collagen-induced arthritis (CIA) in rats and explore its mechanisms. Methods: Female Lewis rats were immunized with bovine type II collagen (CII) to induce arthritis. The rats with CIA were randomly divided into three groups: 5% GS control group, 2.5 mg/kg PTX treatment group and 1 mg/kg methotrexate (MTX) positive control group. The drugs were administered by intraperitoneal injection on the second day after arthritis onset. The body weights, arthritis scores and paw volumes were observed consecutively. The ankle joints of rats were collected for X-ray examination and histological evaluation. Serum samples were collected to test the levels of anti-CII antibodies and cytokines. Results: Body weights were not significantly affected after PTX or MTX treatments (p>0.05). Compared with 5% GS control or MTX treatment groups, PTX group showed significant decrease of arthritis scores and paw volumes (p
- Published
- 2016
247. Electrochemical Polymerization and Characterization of Polyaniline/Carbon Nanotube Composite Films
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Liang Zhao, Xiao-Xia Li, De-Yue Ma, Zhang-Bin Huang, and Guo Yuxiang
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Materials science ,Polyaniline nanofibers ,Electrochemical polymerization ,Composite number ,Carbon nanotube ,law.invention ,Characterization (materials science) ,chemistry.chemical_compound ,Chemical engineering ,chemistry ,Electrochromism ,law ,Polyaniline ,Composite material ,Cyclic voltammetry - Published
- 2016
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248. Outcomes of Phacoemulsification Using Different Size of Clear Corneal Incision in Eyes with Previous Radial Keratotomy
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Frank S. Tsai, Larry Baum, Vishal Jhanji, Jing Shang Zhang, Qi Sheng You, Jing Zhao, Xiu Hua Wan, Xue Liu, Jing Li, Yao Huang, Xiao Xia Li, Jin Da Wang, and Ying Xiong
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Male ,Visual acuity ,genetic structures ,Vision ,medicine.medical_treatment ,Surgical Wound ,Visual Acuity ,Social Sciences ,lcsh:Medicine ,Intraocular lens ,Epithelium ,Cornea ,0302 clinical medicine ,Lens Implantation, Intraocular ,Animal Cells ,Clear corneal incision ,Medicine and Health Sciences ,Psychology ,Medicine ,lcsh:Science ,Keratotomy, Radial ,Multidisciplinary ,Ophthalmic Procedures ,Cataract Surgery ,Middle Aged ,Radial keratotomy ,Treatment Outcome ,Sensory Perception ,Female ,Anatomy ,Cellular Types ,medicine.symptom ,Research Article ,Adult ,medicine.medical_specialty ,Ocular Anatomy ,Surgical and Invasive Medical Procedures ,Dehiscence ,03 medical and health sciences ,Ocular System ,Ophthalmology ,Humans ,Retrospective Studies ,Phacoemulsification ,business.industry ,Wound dehiscence ,Significant difference ,lcsh:R ,Biology and Life Sciences ,Endothelial Cells ,Astigmatism ,Epithelial Cells ,Cell Biology ,medicine.disease ,eye diseases ,Biological Tissue ,030221 ophthalmology & optometry ,Eyes ,lcsh:Q ,sense organs ,business ,Head ,030217 neurology & neurosurgery ,Neuroscience - Abstract
Objective To evaluate visual outcomes and complications after phacoemulsification in eyes with cataract and previous radial keratotomy (RK) cuts using different sizes of clear corneal incisions. Methods The study was a retrospective study. Thirty eyes with cataract and previous RK underwent phacoemulsification and intraocular lens (IOL) implantation. Among them 7 eyes had 8 RK cuts, 13 eyes had 12 RK cuts, and 10 eyes had 16 RK cuts. Phacoemulsification and IOL implantation were performed through a 2.0–3.2 mm clear corneal incision by a single surgeon. In the 8 RK cuts group, 3.2 mm clear corneal incisions were used in 4 eyes, and 3.0 mm clear corneal incisions were used in 3 eyes. In the 12 RK cuts group, 3.2 mm clear corneal incisions were used in 6 eyes, and 2.2 mm clear corneal incisions were used in 7 eyes. In the 16 RK cuts group, 3.2 mm clear corneal incisions were used in 5 eyes, and 2.0 mm clear corneal incisions were used in 5 eyes. Patients were followed up 1 day, 1 week, 1 month, 3 months, 6 months, 1 year, 2 years, and 3 years postoperatively and were examined for the dehiscence of RK cuts during or after the surgery, post-operative best-corrected visual acuity (BCVA), corneal astigmatism, corneal endothelial cell density and complications. Results Successful phacoemulsification with IOL implantation was performed in all eyes. No wound dehiscence was noted in any eyes with 8 or 12 RK cuts. Wound dehiscence was noted in 2 eyes with 16 RK cuts. The dehiscence of RK cuts was closed successfully by injecting an air bubble with or without viscoelastic agent into the anterior chamber at the end of surgery. During the follow-up, the cuts were well apposed in all eyes, and no new dehiscence of RK cuts was noted. At the last follow-up, mean BCVA (0.2 ± 0.18 logMAR) was better than preoperative BCVA(0.45±0.19 logMAR) (P < 0.001). There was no significant difference between the long-term preoperative and postoperative mean corneal astigmatism (P = 0.3). However, there was a significant reduction in postoperative corneal endothelial cell density (1866.5±773.9 / mm2 vs 2421.7±655.7 / mm2) (P < 0.001). Conclusions Phacoemulsification and IOL implantation with clear corneal incisions in eyes with previous RK were associated with good surgical outcomes. Wound dehiscence was not specificaly related to the size of clear corneal incision during phacoemulsification in these eyes.
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- 2016
249. Development and Oxidation Resistance of Si-Modifide MCrAlY Coatings on Nb-Base Alloy
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Xiao Xia Li and Chun Gen Zhou
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Materials science ,Mechanical Engineering ,Middle layer ,Metallurgy ,Alloy ,engineering.material ,Condensed Matter Physics ,Microstructure ,Isothermal process ,chemistry.chemical_compound ,chemistry ,Mechanics of Materials ,Silicide ,Cementation (metallurgy) ,engineering ,Oxygen diffusion ,General Materials Science ,Oxidation resistance - Abstract
Halide-activated pack cementation and Air plasma spraying methods were utilized to deposit Si-modified MCrAlY coatings. Nb-base alloys were coated with MCrAlY by Air plasma spraying and followed by pack siliconizing process at 1100°C for 8h and 10h. The pack powders were consisted of 5 Wt.℅NH4Cl、35 Wt.℅Si、60 Wt.℅Al2O3. Si-modified MCrAlY coatings have three-layer microstructure. The outer layer was composed of NbSi2 and Nb3Ni2.4Cr1.6Si6, while the middle layer comprised the compound of Nb、Ti、Ni、Cr、Si. The inner layer adjacent to the substrate was silicide. Isothermal oxidation resistance of Si-modified MCrAlY coatings was tested at 1250°C in static air. Si-modified MCrAlY coatings had excellent oxidation resistance, because continuous Cr2O3 and SiO2 scales which serve as obstacle of oxygen diffusion were formed after oxidation.
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- 2007
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250. Synthesis and photoluminescence properties of (Y,Gd)Al3(BO3)4:Tb3+ under VUV excitation
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Xiao Xia Li and Yu Hua Wang
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chemistry.chemical_classification ,Photoluminescence ,Materials science ,Thermal decomposition ,Analytical chemistry ,Condensed Matter Physics ,chemistry ,Atomic electron transition ,Impurity ,General Materials Science ,Emission spectrum ,Luminescence ,Inorganic compound ,Excitation - Abstract
Single phase of Y x Gd 0.5− x Tb 0.5 Al 3 (BO 3 ) 4 (0 ≤ x ≤ 0.5) was prepared by the thermal decomposition of the corresponding nitrates. The main broad band in 120–178 nm and some other bands in 178–288 nm were observed in the excitation spectrum of Gd 0.5 Tb 0.5 Al 3 (BO 3 ) 4 monitored at 541 nm. The former could be assigned to overlapped absorptions among the f → d transition of Gd 3+ , charge transfer bands of O 2− → Ln 3+ (Ln = Tb, Gd) and BO 3 groups. The latter was ascribed to 4f 8 → 4f 7 5d transitions of Tb 3+ . Under 147 nm excitation the maximum emission peak was observed at about 541 nm in the emission spectrum of Gd 0.5 Tb 0.5 Al 3 (BO 3 ) 4 , which was due to the 5 D 4 → 7 F 5 transition of Tb 3+ ; when substituting Gd 3+ with appropriate Y 3+ , the emission intensity of the 5 D 4 → 7 F 5 transition of Tb 3+ increased, and the optimum emission was obtained at x = 0.1 in Y x Gd 0.5− x Tb 0.5 Al 3 (BO 3 ) 4 . This could be due to that electronic transitions occurred from O 2− : 2 p 6 to Y 3+ : 4 p 6 (4d + 5s) and the absorbed energy transferred to Tb 3+ finally, as observed in the excitation spectrum of Y 0.1 Gd 0.4 Tb 0.5 Al 3 (BO 3 ) 4 . The decay time of the 5 D 4 → 7 F 5 transition of Tb 3+ decreased after Y 3+ replacing Gd 3+ , which could be attributed to increasing defect impurities in Y 0.1 Gd 0.4 Tb 0.5 Al 3 (BO 3 ) 4 under 147 nm excitation.
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- 2007
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