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Preparation of ternary Cr_2 O_3-SiC-TiO_2 composites for the photocatalytic production of hydrogen

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Particuology 2012年第1期10卷 46-50页

作者： Yaojun Zhang Yong Xu Tuo Li yachao wang School of Material Science and Engineering Xi＇an University of Architecture and Technology Xi＇an 710055 China State Key Laboratory of Architecture Science and Technology in West China （XAUAT） Xi＇an University of Architecture and Technology Xi＇an 710055 China

Novel ternary Cr2O3-SiC-TiO2 composites were synthesized by implanting Cr3＋ into SiC-TiO2 via sol-gel and impregnation approaches. The results from X-ray diffraction, scanning electron microscopy and trans- mission electron microscopy show that the Cr3. species were doped onto the surface of the SiC-TiO2 carrier. The diffuse reflectance ultraviolet-visible absorption spectra revealed that the absorption edges of the ternary Cr2O3-SiC-TiO2 composites were gradually shifted red with increasing chromium content. The luminescence intensities of the composites decreased with increasing doped Cr3＋ content due to the reduction in the number of recombination sites of electron-hole pairs. The ternary Cr2O3-SiC-TiO2 com- posites showed high hydrogen-producing activities, which probably results from the formation of donor levels of the Cr3＋ species in the forbidden band of the SiC semiconductor.

关键词： Ternary compositesPhotocatalysisHydrogen productionChromium species

Ill-conditioned problems of dam safety monitoring models and their processing methods

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Science China(Technological Sciences) 2011年第12期54卷 3275-3280页

作者： GU ChongShi wang yachao PENG Yan XU BaoSon State Key Laboratory of Hydrology-Water Resources and Hydraulic Engineering Hohai University Nanjing 210098 China College of Water-conservancy and Hydropower Engineering Hohai University Nanjing 210098 China National Engineering Research Center of Water Resources Efficient Utilization and Engineering Safety Hohai University Nanjing 210098 China

The focus of this paper is the ill-conditioned problems in the dam safety monitoring model. The reasons to give rise to the ill-conditioned problems in statistical models,deterministic models and hybrid models are analyzed in detail,and the criterions for ill-conditioned models are investigated. It is shown that safety monitoring models are not easy to be ill-conditioned if the number of influence factors is less than seven. Moreover,the models have a high accuracy and can meet the engineering requirements. Another frequently encountered problem in establishing a safety monitoring model is the existence of inflection points,which are often present in the mathematical model for the hydraulic components in deterministic models and hybrid models. The conditions for inflection points are studied and their treatments are suggested. Numerical example indicates that the treatments proposed in this paper are effective in removing the ill-conditioned problems.

关键词： dam safety monitoring model ill-conditioned processing method

Improvement of the conversion efficiency of Mg_(3)Sb_(2)thermoelectric devices through optimizing the resistivity of the MgSbNi barrier layer

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Journal of Materials Science & Technology 2024年第1期168卷 208-214页

作者： Huimin Zhang yachao wang Zuhair A.Munir Yongzhong Zhang Wenhao Fan Shaoping Chen College of Materials Science and Engineering Taiyuan University of TechnologyTaiyuan030024China Capital Aerospace Machinery Company Beijing100076China Department of Material Science and Engineering University of CaliforniaDavisCalifornia95616United States of America College of Physics and Optoelectronics Taiyuan University of TechnologyTaiyuan030024China Instrumental Analysis Center of Taiyuan University of Technology Taiyuan030024China

Mg_(3)Sb_(2)-based thermoelectric materials have been the focus of widespread investigations as promising candidates for the harvesting of waste *** stability and service performance are key points for the commercial applications of these *** utilized Mg_(4.3)Sb_(3)Ni as a barrier layer to improve the thermal stability of Mg 3 Sb 2-based ***,its intrinsic high resistivity contributed nega-tively to the desired performance of the *** this work,we investigated two other Mg-Sb-Ni ternary phases,MgSbNi and MgSbNi_(2),as new barrier layer materials to connect with Mg_(3.2)Sb_(2)Y_(0.05).The results show that the efficiency of the Mg_(1.2)SbNi/Mg_(3.2)Sb_(2)Y_(0.05)/Mg_(1.2)SbNi joint is increased by 33%relative to the higher Mg-content barriers due to lower *** system exhibited good interfacial compatibility and showed little change with aging at 673 K for 20 days.

关键词： Mg_(3)Sb_(2) Mg_(1.2)SbNi Barrier layer Conversion efficiency

L^0-CONVEX COMPACTNESS AND RANDOM NORMAL STRUCTURE IN L^0(F,B)

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Acta Mathematica Scientia 2020年第2期40卷 457-469页

作者： Tiexin GUO Erxin ZHANG yachao wang George YUAN School of Mathematics and Statistics Central South UniversityChangsha 410083China Centre for Financial Engineering Soochow UniversitySuzhou 215006China

Let(B,||·||)be a Banach space,(?,F,P)a probability space,and L^0(F,B)the set of equivalence classes of strong random elements(or strongly measurable functions)from(?,F,P)to(B,||·||).It is well known that L^0(F,B)becomes a complete random normed module,which has played an important role in the process of applications of random normed modules to the theory of Lebesgue-Bochner function spaces and random operator *** V be a closed convex subset of B and L^0(F,V)the set of equivalence classes of strong random elements from(?,F,P)to *** central purpose of this article is to prove the following two results:(1)L^0(F,V)is L^0-convexly compact if and only if V is weakly compact;(2)L^0(F,V)has random normal structure if V is weakly compact and has normal *** an application,a general random fixed point theorem for a strong random nonexpansive operator is given,which generalizes and improves several well known *** hope that our new method,namely skillfully combining measurable selection theorems,the theory of random normed modules,and Banach space techniques,can be applied in the other related aspects.

关键词： Complete random normed modules fixed point theorem L^0-convex compactness random normal structure random nonexpansive operators

Effects of n-3 Fatty Acids Supplementation on Performance, Relative Organ Weight and Fatty Acid Composition of Thigh Meat in Broiler Chickens

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Animal Husbandry and Feed Science 2018年第5期10卷 287-292页

作者： Li Yuanfeng wang yachao Ao Xiang He Jian College of Life Science and Engineering Southwest University of Science and Technology Swine Research Institute Tie Qi Li Shi Group.Co.

This study was conducted to evaluate the effects of dietary supplementation with marine microbe accumulating n-3 fatty acids on growth performance, relative organ weight and fatty acid composition of thigh meat in broilers. A total of 480 broilers were randomly allotted to three treat-ments with eight replications per treatment and 20 chicks per pen. A corn-soybean meal-based diet was formulated as a control diet and the broilers were then provided with one of the following dietary treatments:(1) CON(basal diet);(2) N0.1(basal diet+0.10% marine microbe accumulating n-3 fatty acids);(3) N0.2(basal diet+0.20% marine microbe accumulating n-3 fatty acids). No significant differences were observed in the growth performance or the relative organ weight among treatments. However, the levels of saturated fatty acids(SFA) and monounsaturated fatty acids(MUFA)were significantly lower(P<0.05) in groups that received the n-3 fatty acids treatments, whereas polyunsaturated fatty acids(PUFA) were increased(P<0.05) significantly in these groups. Overall, these results indicate that dietary supplementation with marine microbe accumulating n-3 fatty acids can increase PUFA and decrease SFA and MUFA in thigh meat.

关键词： Broiler Fatty acid composition Marine microbe accumulating n-3 fatty acids Growth performance Relative organ weight

Effects of Dietary Yeast Cell Wall Polysaccharides Supplementation to Late Gestation and Lactation Diets on Reproductive Performance and Blood Profiles of Sows and Their Offspring

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Animal Husbandry and Feed Science 2018年第1期10卷 27-32页

作者： wang yachao Li Yuanfeng Ao Xiang He Jian College of Life Science and Engineering Southwest University of Science and Technology Swine Research Institute Tie Qi Li Shi Group.Co.

This study was conducted to determine the effects of yeast cell wall polysaccharides（YCWP） on reproductive performance, serum profiles and milk composition during late gestation and lactation. A total of 96 sows（Landrace × Yorkshire） were blocked on a basis of breed, parity（2-3）and their respective d 85 of gestation, and then randomly allotted to the following three dietary treatments： CON（basal diet, treatment 1）, YCWP1（CON＋0.2% YCWP, treatment 2） and YCWP2（CON＋0.4% YCWP, treatment 3）. The experiment lasted from d 85 of gestation to weaning（d 21 of lactation）. Sows fed YCWP diets had lower backfat thickness reduction from postpartum to weaning（ P〈0.05）. The supplementation of YCWP tended to increase litter weight at weaning（P=0.08） compared with CON. The non-lipid and total milk solids in colostrum was improved by YCWP2（P〈0.05）.No differences were observed in milk composition among dietary treatments（ P〉0.05）. The supplementation of YCWP decreased（P〈0.05） the levels of alanine amino transferase（ALT）, aspartate amino transferase（AST）, while it did not affect（ P〉0.05） alkaline phosphatase（ALP）, total protein（TP）,albumin（ALB）, globulin（GLB）, glucose（GLU）, total cholesterol（TC）, triglyceride（TG） or immunoglobulin G（IgG） in the sow serum. The serum IgG of piglets was increased by the YCWP. The levels of serum ALT and AST were reduced（P〈0.05） for suckling piglets in YCWP treatments. Taken together, the results of current studies might indicate beneficial effects of YCWP supplementation to late gestation and lactation diets on the sow productivity by improving litter weight at weaning, reducing backfat loss, and increasing serum IgG concentrations of piglets.

关键词： Colostrum Litter performance Sow performance Yeast cell wall polysaccharides

基于微分局部均值分解的旋转机械故障诊断方法

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机械工程学报 2014年第11期50卷 101-107页

作者：孟宗王亚超燕山大学河北省测试计量技术及仪器重点实验室秦皇岛066004

提出一种基于微分局部均值分解(Differential local mean decomposition,DLMD)的旋转机械故障诊断方法。该方法在局部均值分解(Local mean decomposition,LMD)过程中融入微分和积分运算。对原始信号进行k阶微分,然后对微分后信号进行LM... 详细信息

提出一种基于微分局部均值分解(Differential local mean decomposition,DLMD)的旋转机械故障诊断方法。该方法在局部均值分解(Local mean decomposition,LMD)过程中融入微分和积分运算。对原始信号进行k阶微分,然后对微分后信号进行LMD分解,对分解得到的各乘积函数(Production function,PF)分量循环进行一次积分和一阶LMD分解,直至循环k次,得到m个PF分量和残余分量,将所有PF分量的瞬时幅值和瞬时频率组合,便可以得到原始信号完整时频分布。将该方法应用于旋转机械故障诊断研究中,通过仿真和试验进行分析研究,结果表明,基于微分局部均值分解的旋转机械故障诊断方法能够有效地抑制虚假干扰频率,提高旋转机械故障诊断准确性。

关键词：微分局部均值分解旋转机械故障诊断

Effects of Xylooligosaccharide(XOS)and Probiotics(PRO)on Production Performance,Egg Quality and Intestinal Short-chain Fatty Acids of Laying Hens in Late Laying Period

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Animal Husbandry and Feed Science 2020年第1期12卷 21-25页

作者： Xiao Xia wang yachao He Jian Li Yuanfeng School of Life Science and Engineering Southwest University of Science and TechnologyMianyang 621000China Feng Guangde Laboratory of Tie Qi Li Shi Group Mianyang 621000China

[Objective]The paper was to study the effects of xylooligosaccharide(XOS)and probiotics(PRO)and their interaction on the production performance,egg quality and intestinal short-chain fatty acids of laying hens in late laying period.[Method]A total of 36074-week-old Romain brown laying hens were randomly divided into four groups,six replicates each group and 15 chickens each *** trial lasted 63 *** laying hens in control group(CON)were fed with basal diet,and those in experimental groups were fed with the basal diets adding with 150 mg/kg XOS(XOS group),100 mg/kg probiotics(PRO group),150 mg/kg XOS+100 mg/kg probiotics(XOS-PRO group).[Result]Compared with the control group,the laying rate,daily egg production,yolk ratio,colonic acetic acid and caecal propionic acid in XOS group increased significantly(P0.05),but significantly increased colonic acetic acid(P<0.05).XOS and PRO had no interaction effect on the production performance,egg quality and intestinal short-chain fatty acids of laying hens in late laying period(P<0.05).[Conclusion]Adding XOS to the diet of laying hens in late laying period could increase the content of short-chain fatty acids in the hindgut of laying hens,and effectively improve the production performance and egg quality of laying hens in late laying *** PRO to the diet did not significantly improve the production performance and egg quality of laying hens,and there was no interaction effect between XOS and PRO.

关键词： Laying hens in late laying period Xylooligosaccharide(XOS) Probiotics(PRO) Production performance Egg quality

Multi-dimensional database design and implementation of dam safety monitoring system

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Water Science and Engineering 2008年第3期1卷 112-120页

作者： Zhao Erfeng wang yachao Jiang Yufeng Zhang Lei Yu Hong National Engineering Research Center of Water Resources Efficient Utilization and Engineering Safety Hohai University Nanjing 210098 P. R. China College of Water Conservancy and Hydropower Engineering Hohai University Nanjing 210098 P. R. China

To improve the effectiveness of dam safety monitoring database systems, the development process of a multi-dimensional conceptual data model was analyzed and a logic design wasachieved in multi-dimensional database mode. The optimal data model was confirmed by identifying data objects, defining relations and reviewing entities. The conversion of relations among entities to external keys and entities and physical attributes to tables and fields was interpreted completely. On this basis, a multi-dimensional database that reflects the management and analysis of a dam safety monitoring system on monitoring data information has been established, for which factual tables and dimensional tables have been designed. Finally, based on service design and user interface design, the dam safety monitoring system has been developed with Delphi as the development tool. This development project shows that the multi-dimensional database can simplify the development process and minimize hidden dangers in the database structure design. It is superior to other dam safety monitoring system development models and can provide a new research direction for system developers.

关键词： dam safety multi-dimensional database conceptual data model database mode monitoring system