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Chinese Chemical Letters 2012年第8期23卷 985-988页

作者： Yan Yan Cui Ya E Ren xiao xuan Liu Department of Polymer Materials and Engineering Faculty of Materials and EnergyGuangdong University of TechnologyGuangzhou 510006China

HTEMPO-functionalized central cores were formed with divinylbenzene in ＇＇core first＇＇ method,and the four or five arms star polymers were built via controlled/living free radical *** four arms star polymers were also prepared with controlled/living free radical photopolymerization in ＇＇arm first＇＇ *** resulting polymers had been confirmed by GPC and 1 H *** showed that the star polymers had low polydispersities and molecular weight（M n） with the 85,000-560,000 g/mol range.

关键词： Controlled/living photopolymerization H-TEMPO Star polymers DVB MMA

Theoretical Studies of g Factors and Defect Structures for Cubic, Tetragonal, and Orthorhombic Fe^＋ Centers in Alkali Halides MX （M=Li, Na; X = F, C1）

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Communications in Theoretical Physics 2006年第1X期46卷 167-170页

作者： LIU Hong-Gang WU xiao-xuan ZHENG Wen-Chen Department of Material Science Sichuan University Chengdu 610064 China Department of Physics Civil Aviation Flying Institute of China Guanghan 618307 China International Centre for Materials Physics the Chinese Academy of Sciences Shenyang 110016 China

The EPR 9 factors for cubic, tetragonal and orthorhombic Fe^＋ centers in alkali halides MX （M= Li, Na; X = F, CI） are calculated from second-order perturbation formulas of g factors based on cluster approach for 3d^7 ions in three symmetries. From calculations, the g factors of these Fe^＋ centers in MX crystals are reasonably explained and the defect structural data for the tetragonal and orthorhombic Fe^＋ centers are estimated. The results are discussed.

关键词： crystal- and ligand-field theory electron paramagnetic resonance defect structure

Effect of Mg and Si on infiltration behavior of Al alloys pressureless infiltration into porous SiCp preforms

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International Journal of Minerals,Metallurgy and Materials 2011年第6期18卷 703-708页

作者： Shu-bin Ren xiao-yu Shen xuan-hui Qu Xin-bo He School of Materials Science and Engineering University of Science and Technology Beijing Beijing 100083 China

The effect of Mg and Si additon to Al matrix on infiltration kinetics and rates of Al alloys pressureless infiltration into porous SiCp preform was investigated by observing the change of infiltration distance with time as the Al alloys infiltrate into SiCp preforms at different *** results show that infiltration of SiCp preforms by Al melt is a thermal activation process and there is an incubation period before the infiltration becomes *** the increase of Mg content in the Al alloys from 0wt% to 8wt%,the infiltration will become much easier,the incubation period becomes shorter and the infiltration rate is faster,but these effects are not obvious when the Mg content is higher than 8wt%.As for Si addition to the Al alloys,it has no obvious effect on the incubation period,but the infiltration rate increases markedly with the increase of Si content from 0wt% to 12wt% and the rate has no obvious change when the content is bigger than 12wt%.The effect of Mg and Si on the incubation period is related to the infiltration mechanism of Al pressureless infiltration into SiCp preforms and their impact on the infiltration rate is a combined result from viscosity and surface tension of Al melt and SiC-Al wetting ability.

关键词： metallic matrix composites infiltration aluminum alloys silicon carbide preforms

Evaluation of nutrient limitation in aquatic ecosystems with nitrogen fixing bacteria

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Journal of Environmental Sciences 2006年第3期18卷 537-542页

作者： WU Gen-fu WU Xue-chang xuan xiao-dong ZHOU Xue-ping College of Life Sciences Zhejiang University Hangzhou 310012 China Science and Technology Committee of Zhejiang Hangzhou 310006 China Institute of Biotechnology Zhejiang University Hangzhou 310029 China

There has always been a great need for simple and accurate bioassays for evaluating nutrient limitation in aquatic ecosystems. Whereas organic carbon is usually considered to be the limiting nutrient for microbial growth in many aquatic ecosystems, there are, however, many water sources that are limited by phosphorus or nitrogen. A method named ＂nitrogen fixing bacterial growth potential＂（NFBGP） test, which is based on pre-culturing of autochthonous （target） microorganisms was described. The method was applied to evaluate phosphorus or nitrogen nutrient limitation in lake and sewage water samples using an isolate of the nitrogen fixing bacterium, Azorhizobium sp. WS6. The results corresponded well to those from the traditional algal growth potential （AGP） test and the bacterial regrowth potential （BRP） test, suggesting that the NFBGP test is a useful supplementary method for evaluating the limiting nutrient, especially phosphorus, in an aquatic environment.

关键词： environment monitoring nitrogen fixing bacterium limiting nutrient phosphorus growth potential

Homologous layered InFeO3(ZnO)m:new promising abradable seal coating materials

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Rare Metals 2018年第2期37卷 79-94页

作者： Wei-Wei Qu xiao-xuan Zhang Bi-Fei Yuan Li-Dong Zhao School of Materials Science and Engineering BeihangUniversityBeijing 100191China China National Petroleum Corporation Greatwall Drilling Company Beijing 100101China

As promising abradable seal coating materials used in high temperature range, the homologous layered InFeO3（ZnO）m （m = 1, 2, 3...20） have attracted great attention. In this short review, we summary the research progress in InFeO3（ZnO）m that were developed in our group. We first introduced a series of conventional abradable seal coating materials as a research motivation. Second, the phase composition and crystal structures of lnFeO3（ZnO）m system were presented. Then, their thermophysical properties, as the most important part, were introduced in detail. At last, the mechanical properties such as hardness, friction coefficient, erosion wear resistance of InFeO3（ZnO）m system were also described. Our summary indicates that InFeO3（ZnO）m sys- tems are promising abradable seal coating materials.

关键词： Abradable seal coating InFeO3(ZnO)m Thermal conductivity Thermal expansion coefficient Mechanical properties

Caution in the use of sedation and endomyocardial biopsy for the management of pediatric acute heart failure caused by endocardial fibroelastosis

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World Journal of Clinical Cases 2023年第22期11卷 5412-5415页

作者： xiao-xuan Xin Yo-Yeng Se School of Hulunbuir Clinical Medicine Inner Mongolia Minzu UniversityHulunbuir 021000Inner Mongolia Autonomous RegionChina Faculty of Medicine The Chinese University of Hong KongHong Kong 999077China Jockey Club College of Veterinary Medicine and Life Sciences City University of Hong KongHong Kong 999077China

Endocardial fibroelastosis(EFE)is commonly considered to be an inflammatory reactive lesion of hyperplasia and deposition of tissue fibers and collagen in the endocardium and/or subendocardium,which is strongly associated with endocardial sclerosis,ventricular remodeling and acute and chronic heart failure,and is one of the important causes for pediatric heart *** diagnosis and treatment are the key factors in determining the prognosis of the *** this paper,we would like to highlight the potential unintended consequences of the use of sedation and biopsy for pediatric acute heart failure caused by EFE and the comprehensive considerations prior to clinical diagnosis.

关键词： Endocardial fibroelastosis Sedation in children Endomyocardial biopsy Comprehensive clinical diagnosis

Effect of Solution Treatment on the Microstructure and Mechanical Properties of Sand-Cast Mg–9Gd–4Y–0.5Zr Alloy

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Acta Metallurgica Sinica(English Letters) 2018年第2期31卷 189-198页

作者： Jing-Li Li Na Zhang xiao-xuan Wang Di Wu Rong-Shi Chen The Group of Magnesium Alloys and Their Applications Institute of Metal Research Chinese Academy of Sciences Shenyang 110016 China School of Materials Science and Engineering University of Science and Technology of China Hefei 230026 China AVIC Shenyang Liming Aero--Engine Group Corporation Shenyang 110043 China

Sand-cast Mg–9Gd–4Y–0.5 Zr（wt%） alloy was solution-treated at 500–565 ℃ in the time range of 0.5–30 h in air or vacuum to investigate its microstructure evolution and mechanical properties. The results showed that solution treatment temperature had a significant influence on the dissolving rate of eutectic phase and grain growth. Taken both of them into consideration, 510–520 ℃ was considered to be the optimum solution treatment temperature range for this *** should be noted that the trace（0.4–0.9 vol%） and insoluble cuboid-shaped phase precipitated during solution treatment was identified to be YH2, of which the hydrogen was thought to come from both the melting and solution heating *** addition, the 3D morphology and dissolving process of Mg24（Gd,Y）5 eutectic phases in the as-cast alloy were also discussed via in-situ observation under X-ray tomography.

关键词： Mg-Gd-Y-Zr alloy Solution treatment Microstructure Rare-earth hydride

Sodium selenite may be not the optimal speciation as an effective therapy for arsenic-induced anxiety-/depression-like behavior

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World Journal of Psychiatry 2022年第9期12卷 1255-1257页

作者： xiao-Hua Ren xiao-xuan Wang Lian-Ping He School of Medicine Taizhou UniversityTaizhou 318000Zhejiang ProvinceChina

Major depressive disorder is a serious and prevalent neuropsychiatric disorder,affecting more than 350 million people ***,sodium selenite(SS)was selected as the selenite supplement to improve the behavior in a mouse model of depression induced by *** may be not the optimal speciation for selenite supplementation and the source of the SS used in the study was not *** are many mouse models of depression and anxiety;however,in the current study,a classical mouse model of depression was not ***,several questions still need to be further *** together,the results indicate that SS may be not the optimal speciation as an effective therapy for As-induced anxiety-/depression-like behavior.

关键词： Depression Arsenic Major depressive disorder Sodium selenite Optimal speciation

Controlled Radical Photopolymerization of n-Butyl Methacrylate in Bluk Mediated by HTEMPO

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Chinese Chemical Letters 2006年第8期17卷 1109-1112页

作者： xiao xuan LIU Mei HAN Lun Yong DUAN Guang Guo WU Department of Chemistry College of Science Shantou University Shantou 515063

Controlled radical photopolymerization of n-butyl methacrylate（n-BMA） mediated by 4-hydroxy-2,2,6,6-tetramethyl-1-piperidinyloxy（HTEMPO） was carried out in bulk at ambient temperature. It was found that obtained n-BMA homopolymers exhibited narrow polydispersities of around 1.4, which was characterized by GPC. Plots of number-average molecular weight vs. conversion and Ln（[Mo]/[M]） vs. time were liner respectively, indicating that was a controlled photopolymerization.

关键词： photopolymerization nitroxide n-butyl methacrylate HTEMPO.

Experimental investigation of propagation mechanisms and fracture morphology for coalbed methane reservoirs

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Petroleum Science 2018年第4期15卷 815-829页

作者： Chi Ai xiao-xuan Li Jun Zhang Dan Jia Wen-Jing Tan College of Petroleum Engineering Northeast Petroleum University College of Geoscience and Technology China University of Petroleum (East China)

Fracture propagation mechanisms in coalbed methane(CBM) reservoirs are very complex due to the development of the internal cleat system. In this paper, the characteristics of initiation and propagation of hydraulic fractures in coal specimens at different angles between the face cleat and the maximum horizontal principal stress were investigated with hydraulic fracturing tests. The results indicate that the interactions between the hydraulic fractures and the cleat system have a major effect on fracture networks. "Step-like’’ fractures were formed in most experiments due to the existence of discontinuous butt cleats. The hydraulic fractures were more likely to divert or propagate along the butt cleat with an increase in the angles and a decrease in the horizontal principal stress difference. An increase in the injection rate and a decrease in the fracturing fluid viscosity were more conducive to fracture networks. In addition, the influence on fracture propagation of the residual coal fines in the wellbore was also studied. The existence of coal fines was an obstacle in fracturing, and no effective connection can be formed between fractures. The experimental investigation revealed the fracture propagation mechanisms and can provide guidance for hydraulic fracturing design of CBM reservoirs.

关键词： Coalbed methane reservoir Butt cleat Propagation mechanisms Fracture morphology Step-like fractures