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Research on System Dynamic of Buying Work Safety Services in Small and Medium-Sized Enterprises

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Journal of Systems Science and Systems Engineering 2021年第3期30卷 339-362页

作者： Suxia Liu Hangfeng Li qiang mei School of Management Jiangsu UniversityZhenjiang212013China

Buying work safety services from intermediaries is a new and important approach to improve the work safety in small and medium-sized enterprises(SMEs).The existing literature addresses the significance and effectiveness of the service model but it ignores the dynamic game relationship between relevant stakeholders when SMEs choose to purchase the services under bounded ***,this study aims to analyse this dynamic game relationship based on evolutionary game ***,dynamic simulations of the evolutionary game model are applied to determine the impact of major factors for three stakeholders(SMEs,governments,and safety service agents),examine stability strategies,and identify modes of equilibrium under different subsidy *** results of simulation are as ***,the results explain that how the major factors(service price,the quality of service,government subsidy,etc.)affect the system dynamic force of buying work safety ***,when the subsidy strategy is static payment,the selection of the stakeholders fluctuates and is not ***,when the subsidy strategy is a dynamic payment,the evolutionary game process converges to a stable state,which indicates that an evolutionarily stable strategy exists under the dynamic subsidy ***,the stable state and equilibrium values are not affected by the different initial *** results of this study offer a certain reference for the government to guide the implementation of the purchase of work safety or other services in SMEs.

关键词： Small and medium-sized enterprises(SMEs) work safety services evolutionary game theory system dynamics

NECESSARY AND SUFFICIENT CONDITION FOR GLOBAL CONTROLLABILITY OF A CLASS OF AFFINE NONLINEAR SYSTEMS

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Journal of Systems Science & Complexity 2007年第4期20卷 492-500页

作者： Yimin SUN Shengwei mei qiang LU Department of Electrical Engineering Tsinghua University Beijing 100084 China

In this paper, we investigate the global controllability of a class of n-dimensional affine nonlinear systems with n- 1 controls and constant control matrix. A necessary and sufficient condition for its global controllability has been obtained by using the methods recently developed. Furthermore, we generalize the above result to a class of affine nonlinear systems with a block-triangular-like structure. Finally, we will give three examples to show the applications of our results.

关键词： Affine nonlinear systems block-triangular-like structure global controllability vector field

Synthesis of 1,1'-binaphthyl-2,2'-diamine from 2-naphthol under atmospheric pressure

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Chinese Chemical Letters 2009年第10期20卷 1150-1152页

作者： qiang Feng Chao Zhang qiang Tang mei Ming Luo Key Laboratory of Green Chemistry & Technology of Ministry of Education College of Chemistry Sichuan University Chengdu 610064 China

A practical protocol to obtain 1,1′-binaphthyl-2,2′-diamine was developed from 2-naphthol and 2-naphthylhydrazine under mild conditions： solvent-free, 125-130 ℃, atmospheric pressure. The convenient procedure make... 详细信息

关键词： 1,1′-Binaphthyl-2,2′-diamine 2-Naphthol 2-Naphthylhydrazine Synthesis

Ultrasonicwave-assisted tandem-reaction for synthesis of symmetrical vicinal diamines

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Chinese Chemical Letters 2007年第12期18卷 1469-1470页

作者： Gen Rong qiang Xiang mei Wu Qin Wang Wen Pei College of Chemical Engineering and Materials Zhejiang University of Technology Hangzhou 310014 China

A practical synthesis of symmetrical vicinal diamines with broad chemistry scope is described. The key step is the ultrasonicwave promoted tandem-reaction, two-step reaction sequence combining Mannich double condensations with benzo- triazole, glyoxal and primary or secondary amines and reduction of the bis（benzotriazole）-adducts with sodium borohydride proceeded smoothly in tetrahydrofuran in high yield at room temperature.

关键词： Vicinal diamine Benzotriazole Glyoxal Mannich reaction Synthesis

Polymerizable Ionic Liquid Copolymer P(MMA-co-BVIm-Br) and Its Effect on the Surface Wettability of PVDF Blend Membranes

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Chinese Journal of Polymer Science 2015年第6期33卷 857-868页

作者：杜春慧 Xu-min Ma Chun-jin Wu mei-qiang Cai Meng-xin Hu Ting Wang School of Environmental Science and Engineering Zhejiang Gongshang University Schoolof Food Science and Biotechnology Zhejiang Gongshang University

Polymerizable ionic liquid copolymer P（MMA-co-BVIm-Br） was synthesized by radical polymerization technique, and characterized by Fourier transform infrared spectrometry （FTIR）, 1H Nuclear magnetic resonance （1H-NMR） and gel permeation chromatography （GPC）. The resulting copolymer was used to prepare poly（vinylidene fluoride）（PVDF） blend membranes via a phase inversion method. The effects of the copolymer on the polymorphism, surface wettability and zeta potential （0 of the blend membranes were investigated by ATR-FTIR, contact angle instrument and zeta potential analyzer. Scanning electron microscopy （SEM and SEM-EDS） was also applied to investigate the morphology and the surface element changes of the fabricated membranes. The results indicated that P（MMA-co-BVIm-Br） copolymer existed on the surface of the membrane which made the blend membrane have a positive surface during the experimental pH range. The copolymer was also in favor of the formation of βcrystal phase in PVDF membranes. The contact angle experiment indicated that P（MMA-co-BVIm-Br） copolymer could switch the wettability of the blend membranes from hydrophilic to hydrophobic by exchanging Br- anion with PF6-. Compared with pure PVDF membranes, the water flux and water recovery flux of the blend membranes were enhanced obviously. The results from the flux recovery ratio （FR） and total fouling ratio （Rt） all suggested that the blend membranes had good anti-fouling properties.

关键词： PVDF membrane Polymerized ionic liquid Surface wettability Anti-fouling performance.

日本彦根城博物馆藏《琴用指法》抄本性质新证

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中国音乐学 2022年第3期3卷 36-42页

作者：梅强重庆师范大学国际汉语文化学院

彦根城本《琴用指法》异体率和用字习惯与《碣石调幽兰》差异明显,二者绝非截自同一抄本。《琴用指法》抄本存在一些“倭俗讹字”,具有平安后期以来日人抄本的文字特征,很难说是我国许多学者所认为的唐人抄本。抄手对于抄写内容只是机... 详细信息

彦根城本《琴用指法》异体率和用字习惯与《碣石调幽兰》差异明显,二者绝非截自同一抄本。《琴用指法》抄本存在一些“倭俗讹字”,具有平安后期以来日人抄本的文字特征,很难说是我国许多学者所认为的唐人抄本。抄手对于抄写内容只是机械地复制,并无能力校改其中的琴学术语及演奏方法等“术业之误”。但相对而言,它已是我们今天所见最早的指法释义文献,我们应当辩证地认识其音乐史及音乐文献价值。

关键词：《琴用指法》抄本异体率倭俗讹字

照明光源及纸张色彩对传统书法作品展陈喜好的影响

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光谱学与光谱分析 2016年第11期36卷 3664-3670页

作者：刘强唐美华武汉大学印刷与包装系湖北武汉430079 武汉大学深圳研究院广东深圳518000 华南理工大学制浆造纸工程国家重点实验室广东广州510640

书法是中国传统文化独有的文字艺术表现形式。书法作品的展陈喜好,其实质为色彩组合喜好中的色彩图形喜好问题。本研究针对现阶段书法作品展陈方式在颜色科学层面缺乏合理依据的问题,以主客观实验为基础,就照明光源及纸张色彩对传统书... 详细信息

书法是中国传统文化独有的文字艺术表现形式。书法作品的展陈喜好,其实质为色彩组合喜好中的色彩图形喜好问题。本研究针对现阶段书法作品展陈方式在颜色科学层面缺乏合理依据的问题,以主客观实验为基础,就照明光源及纸张色彩对传统书法展陈喜好的影响进行了分析与讨论。研究首先通过相关色温2 500,3 500,4 500,5 500和6 500K共五种典型LED照明光源相对光谱功率分布以及白色、黄白、浅白、红色、橙色共五种典型书法纸张光谱反射率信息的测量,获取光源及纸张色彩原始信息,并分别将其转换至CIEXYZ以及CIECAM02颜色空间。随后,将光源及纸张色彩属性与基于40名观察者心理物理学实验的1 000组书法展陈喜好数据进行关联性分析,进而从相关性分析、多元回归分析以及正态分布分析等多个统计学角度对传统书法作品展陈喜好的影响因素进行讨论。实验结果显示,传统书法作品展陈照明喜好与普通场景色彩喜好相比具有显著的特殊性,其喜好程度与明度对比、色相对比等色彩属性相关性较低,而主要受光源因素的影响。本研究的开展,将为当前传统书法作品的展陈照明工作提供有效的理论与方法参考,对于当前博物馆及美术馆的光源设计工作具有一定的指导意义。

关键词：光谱功率分布光谱反射率书法作品展陈喜好

The Pig Lhx8 Gene:cDNA Cloning,Bioinformatic Analysis and Expression Level in Tissues and Preimplantation Embryos

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Agricultural Sciences in China 2009年第12期8卷 1503-1510页

作者： FANG Wei,LI Gui-qiang,LI mei-li,WANG Wei and XU Yin-xue College of Animal Science & Technology,Nanjing Agricultural University,Nanjing 210095,P.R.China [a] College of Animal Science & Technology Nanjing Agricultural University Nanjing 210095 P.R. China

Evidence has shown in mouse that Lhx8 is a critical factor for maintenance and differentiation of the oocyte during early oogenesis. In the current paper, attempts were made to clone and characterize a gene encoding Lhx8 from pig. Rapid amplification of cDNA ends （RACE） gave rise to a full-length of Lhx8 which contained 1 681 bp nucleotides, with a complete open reading frame of 885 bp, encoding a 295 amino acid polypeptide. Homology search and sequence multialignment demonstrated that the deduced pig Lhx8 protein sequence shared a high identity with Lhx8 from other mammals, including several highly conservative motifs and amino acids. The phylogenetic tree of the LIM superfamily proteins has been constructed to reveal the evolutionary relationship of various species. RT-PCR analysis showed that the Lhx8 gene was expressed in gonad and immunity tissues. In preimplantation embryos, Lhx8 mRNA expression profiling using realtime PCR revealed that its mRNA levels were highest in 4-cell stage embryos and gradually decreased until the blastocyst stage.

关键词： pig LhxS molecular cloning mRNA expression qRT-PCR preimplantation embryos

Microadenocarcinoma in the head of the pancreas

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Chinese Medical Journal 2007年第20期120卷 1853-1854页

作者： LANG Zhi-qiang QU Gui-mei YAO Wei-dong JIANG Lei Department of Pathology Yantai Yuhuangding Hospital Medical College of Qingdao University Yantai 264000 China

Microadenocarcinoma （MA） is a rare variant of ductal carcinoma of the pancreas. Although it is generally accepted that the MA is a pattern of owth, some researchers regard it as a distinctive entity. Here we report ... 详细信息

关键词： microadenocarcinoma pancreas