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L-Cysteine-assisted Synthesis of Copper Gallium Sulfide Microspheres

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Chemical Research in Chinese Universities 2012年第3期28卷 395-398页

作者： liang Xiao-juan Zhong Jia-song CAI Qian HUANG Hai-yu LIU Hai-tao XIANG wei-dong SUN Jun-cai College of Chemistry and Materials Engineering Wenzhou UniversityWenzhou 325035P.R.China Institute of Materials and Technology Dalian Maritime UniversityDalian 116026P.R.China College of Materials Science and Engineering Tongji UniversityShanghai 201804P.R.China

An effective L-cysteine-assisted synthetic route has been successfully developed to prepare copper gallium sulfide（CuGaS2） microspheres under solvothermal conditions with CuCI2.2HzO, GaC13 and L-cysteine as source materials, in which L-cysteine was used as the sulfide source and complexing molecule. The experiments revealed that the synthesized sample was of a typical CuGaS2 tetragonal structure. Moreover, the prepared CuGaS2 crystals consisting of microspheres made up of nanoflakes, and the diameter of the nanoflakes was about 20 nm. Raman spectrum of the obtained CuGaS2 exhibits a high-intensity peak of the A1 mode at 306 cm^-1. Meanwhile, a possible growth mechanism was proposed based on the investigations.

关键词： Copper gallium sulfide L-Cysteine Raman spectrum

Critical Temperature Characteristics of Layered High-Temperature Superconductor Under Pressure

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Communications in Theoretical Physics 2009年第4期51卷 761-764页

作者： liang Fang-Ying Institute of Science and Technology for OPTO-Electronic Information of Yantai University Yantai 264005 China

We consider a Ginzburg-Landau modified model of layered high-temperature superconductor under pressure. We have theoretically studied the relation between the pressure and the temperature of layered high-temperature superconductor. If the pressure is not a constant, we have a relation of quadratic equation between the pressure and the temperature of layered high-temperature superconductor. In a special case, we find the critical temperature decreases with further increasing pressure. In another special ease, the critical temperature increases with further increasing pressure.

关键词： pressure effects transition temperature variations layered superconductor

Dynamic Expression of MicroRNA-127 During Porcine Prenatal and Postnatal Skeletal Muscle Development

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Journal of Integrative Agriculture 2014年第6期13卷 1331-1339页

作者： YANG Ya-lan LI Yan liang Ru-yi ZHOU Rong AO hong MU Yu-lian YANG Shu-lin LI Kui TANG Zhong-lin Key Laboratory of Farm Animal Genetic Resources and Germplasm Innovation Ministry of Agriculture/Institute of Animal ScienceChinese Academy of Agricultural Sciences Department of Animal Genetics Breeding and ReproductionCollege of Animal Science and TechnologyNanjing Agricultural University

MicroRNAs （miRNAs）, evolutionarily conserved non-coding RNAs in length 21-24 bp, play a critical role in skeletal muscle development. In this study, to explore the function of mircoRNA-127 in porcine skeletal muscle development, eight tissue samples from adult pigs and longissimus muscle samples at 26 developmental stages were collected from Tongcheng and Landrace pigs. The spatial-temporal expression proifles of miRNA-127 were carried out using step-loop quantitative real-time PCR （stem-loop RT-PCR）. To explore the molecular functions of miRNA-127, we predicted its target genes and performed functional annotation using bioinformatics methods. Results suggested that miRNA-127 was abundantly expressed in heart, ovary, uterus and spleen tissues and was weakly expressed in liver, lung, kidney and small intestine in both Tongcheng and Landrace pigs. And miRNA-127 showed signiifcant expression differences in heart, ovary, spleen and uterus tissues between these two breeds. miRNA-127 basically kept at a relatively stable high level in middle and later embryonic stages and a low expression level in early embryonic stages and postnatal stages, but the expression levels of miRNA-127 were higher in Tongcheng pigs than in Landrace at most developmental stages. miRNA-127 potentially regulated 240 candidate genes. Results of Gene Ontology and KEGG pathway analysis indicated that these genes could be involved in many molecular functions and mechanisms, such as regulation of the force of heart contraction, regulation of transcription, regulation of T cell differentiation, MAPK signaling pathway and GnRH signaling pathway. Many signiifcantly enriched GO terms and KEGG pathways were related to skeletal muscle development. This study will be helpful to understand the biological function for miRNA-127 and identify candidate gene associated with meat production traits in pigs.

关键词： porcine microRNA-127 expression profiles skeletal muscle development target prediction

Axially Segmented Semiconductor Heteronanowires

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Accounts of Materials Research 2020年第2期1卷 126-136页

作者： Yi Li Tao-Tao Zhuang Chong Zhang liang Wu Shi-Kui Han Shu-hong Yu Division of Nanomaterials&Chemistry Hefei National Laboratory for Physical Sciences at MicroscaleInstitute of EnergyHefei Comprehensive National Science CenterCAS Center for Excellence in NanoscienceInstitute of Biomimetic Materials&ChemistryDepartment of ChemistryUniversity of Science and Technology of ChinaHefeiAnhui 230026China

CONSPECTUS:Programming nanoscale functional objects into complex,sophisticated heterostructures that tremendously outperform their solo objects and even bring about exotic chemical/physical properties offers exciting routes toward a spectrum of applications in photonics and *** development in synthetic chemistry over past decades has enabled a library of hybrid nanostructures,such as core−shell,patchy,dimer,hierarchical/branched ones,***,the material combinations of these non-van der Waals solids are largely limited by the rule of lattice-matched epitaxy *** an emerging class of heterostructures,axially segmented nanowires(ASNWs)offer an alternative but effective approach to epitaxially integrating the conventional non-van der Waals *** large lattice-mismatch tolerance in ASNWs permits vast material combinations,broad size modulations,and flexible interfacial strain engineering,signifying the great potentials for engineering their photon utilizations,band structures,features of charge carriers or excitons,and some other emerging ***,ASNWs with on-demand,high-precision control over composition,shape,dimension,crystal phase,interface,and periodicity remain so far synthetically *** steering the chemoselective reactions,one has access to high-precision *** this Account,we describe the state-of-the-art synthetic strategies for chemoselectivity *** categorize them into(i)unidirectional/bidirectional sequential additions,which include selective area epitaxy,catalyzed growth,and end-facet-seeded growth,and(ii)regiospecific one-off transformations,which include ionic exchange reaction,strain/thermal induced phase segregation and transition,Plateau-Rayleigh instability,regioselective heterogeneous nucleation as ruled by lattice match,defect,and surface charges,and *** uncover the chemical principles behind from thermodynamic and kinetic *** we further offer insights into the

关键词： properties. phonon quantum

PSO-ACSC:a large-scale evolutionary algorithm for image matting

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Frontiers of Computer Science 2020年第6期14卷 31-42页

作者： Yihui liang Han HUANG Zhaoquan CAI School of Computer Science University of Electronic Science and Technology of ChinaZhongshan InstituteZhongshan 528400China School of Software Engineering South China University of TechnologyGuangzhou 510006China Research Department Huizhou UniversityHuizhou 516007China

Image matting is an essential image processing technology due to its wide range of ***-based image matting is one of the main branches of image matting research that estimates alpha mattes by selecting the best pixel *** is essentially a large-scale multi-peak optimization problem of pixel *** study shows that particle swarm optimization(PSO)can effectively optimize the pixel ***,it still suffers from premature convergence problem which often occurs in pixel pair optimization that involves a large number of local *** address this problem,this work presents a parameter-free strategy for PSO called adaptive convergence speed controller(ACSC).ACSC monitors and conditionally controls the particles by competitive pixel pair recombination operator(CPPRO)and pixel pair reset operator(PPRO)during the *** performs CPPRO to improve the competitiveness of a particle when the performance of most of the pixel pairs is worse than that of the best-so-far *** is performed to avoid premature convergence when the alpha mattes regarding two selecleu particles ae liglly *** results show that ACSC significantly enhances the performance of PSO for image matting and provides competitive alpha mattes comparing with state-of-the-art evolutionary algorithms.

关键词： evolutionary computing particle swarm optimization large-scale optimization image matting

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X射线吸收谱研究碳与硅的纳米线/管

光谱学与光谱分析 2006年第3期26卷 571-576页

作者：林良武唐元洪张伟湖南大学材料科学与工程学院湖南长沙410082

由于X射线吸收谱中的总电子产额(TEY)和荧光产额(FLY)具有不同的取样探测深度,分别对样品的表面和体内敏感,因而两者的综合应用为纳米材料的整体分析提供了有力的依据,是透射电子显微镜(TEM)、X射线衍射(XRD)等传统方法分析纳米材料时... 详细信息

由于X射线吸收谱中的总电子产额(TEY)和荧光产额(FLY)具有不同的取样探测深度,分别对样品的表面和体内敏感,因而两者的综合应用为纳米材料的整体分析提供了有力的依据,是透射电子显微镜(TEM)、X射线衍射(XRD)等传统方法分析纳米材料时的补充。同时,通过对TEY和FLY记录的X射线吸收谱的评述,作者认为X射线吸收谱可以准确、可靠地用来进行纳米线和纳米管的生长及其机理、取向、化学键合、缺陷与螺旋性等方面的研究。因此X射线吸收谱具有传统方法无法比拟的优势,是纳米材料研究领域强有力的表征工具。

关键词： X射线吸收谱硅纳米线碳纳米管蓝移

多性能指标下区间二型T-S模糊时滞系统的滤波器设计

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控制与决策 2018年第6期33卷 989-998页

作者：赵涛程冠鸿刘凯梁伟博四川大学电气信息学院成都610065

区间二型T-S模糊时变延迟模型可以有效地处理具有参数不确定的非线性时变时滞系统.针对多性能指标框架下区间二型T-S模糊时变延迟系统的滤波器设计仍然是有待解决的问题,利用Lyapunov-Krasovskii泛函方法,在多性能指标框架下提出前提隶... 详细信息

区间二型T-S模糊时变延迟模型可以有效地处理具有参数不确定的非线性时变时滞系统.针对多性能指标框架下区间二型T-S模糊时变延迟系统的滤波器设计仍然是有待解决的问题,利用Lyapunov-Krasovskii泛函方法,在多性能指标框架下提出前提隶属函数不匹配的区间二型模糊滤波器.利用最新发展的积分不等式,所设计的滤波误差系统可以同时满足耗散性、无源性、H∞和L2-L∞性能.通过矩阵解耦技术,滤波器存在条件可以表示为线性矩阵不等式.最后通过仿真实验验证了所提出方法的有效性.

关键词：区间二型T-S模糊系统时变延迟滤波器设计多性能指标

Thiamine additive engineering enables improved film formation towards high efficiency and moisture stability in perovskite solar cells

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Science China Materials 2022年第2期65卷 321-327页

作者： Peng Zhang Fengren Cao wei Tian liang Li School of Physical Science and Technology Center for Energy Conversion Materials&Physics(CECMP)Jiangsu Key Laboratory of Thin FilmsSoochow UniversitySuzhou 215006China

Perovskite solar cells(PSCs)attract widespread research interest due to their exceptional ***,the instability of the perovskite layer,especially the moisture instability,and existing defects seriously restrict the performance and limit the development of PSCs towards ***,we fabricate moisture-stable and efficient PSCs by incorporating a thiamine(THM)additive into a lead iodide(PbI_(2))precursor using a two-step spin-coating *** strategy enables a better interaction between the THM additive and PbI_(2).Then,a higher energy barrier is produced when the material reacts with A-site cations to form perovskite crystals,resulting in larger grains and better-quality perovskite *** optimization of the concentration of the THM additive,the optimal perovskite achieves improved moisture stability and decreased trap states;thus,the corresponding unencapsulated devices achieve a remarkable power conversion efficiency(PCE)of 21.40%and maintain>92%of their initial PCE after 180 h in ambient air(~50%humidity).The excellent performance is mainly attributed to the fact that THM promotes crystal growth and passivates defects in perovskite films.

关键词： perovskite moisture stability solar cell passivation

Relaxation of Magnetic Nanoparticle Chain without Applied Field

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Communications in Theoretical Physics 2011年第3期55卷 537-540页

作者： HE liang-Ming College of Physics and Electronic Engineering Guangxi University for Nationalities Nanning 530006 China

The relaxation of a one-dimensional magnetic nanoparticle linear chain with lattice constant a is investigated in absence of applied field. There is an equilibrium state （or steady state） where a11 magnetic moments of particles lie along the chain （x-axis）, back to which the magnetic nanoparticle chain at other state will relax. It is found that the relaxation time T= is determined by Tx = 10β×α3. This relaxation is compared with that of single magnetic nanoparticle system.

关键词： magnetic properties of nanostructures