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Synthesis of Alkoxysilanes Bearing β-Diketone Group through Hydrosilylation

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Chinese Chemical Letters 2002年第2期13卷 121-122页

作者： yuan YAO Wei HUANG Ying HUANG yun zhao yu The Center of Molecular Science Institute of ChemistryChinese Academy of SciencesBeijing 100080

Alkoxysilane bearing diketone group was synthesized by hydrosilylation of 3-allyl acetylacetone. It was indicated by the 1H NMR spectrum that the C=O group does not interfere with the synthesis.

关键词： Tydrosilylation alkoxysilane b-diketone.

MODIFICATION OF EPOXY RESIN WITH POLYSILOXANE BEARING PENDANT QUATERNARY AMMONIUM GROUPS

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Chinese Journal of Polymer Science 2002年第6期20卷 537-541页

作者： Zuo-xin Huang Ying Huang yun-zhao yu The State Key Laboratory of Engineering Plastics, Institute of Chemistry Chinese Academy of Sciences, Beijing 100080 China Chinese Acad Sci Inst Chem State Key Lab Engn Plast Beijing 100080 Peoples R China

Polysiloxane bearing pendant quaternary ammonium groups (PSI) was used to modify the surface properties of epoxy resins. In the cured resin, PSI formed the dispersed phase. Remarkable enrichment and gradient distribution of polysiloxane on the surface region of the epoxy resins were demonstrated by XPS analysis. The composition and properties of the surface of PSI-modified epoxy resin, which is in contact with the mold, are dependent on the material of the mold. Through the incorporation. of PSI, epoxy resins with low surface energy and low friction coefficient were obtained. Polysiloxane with lower ionic group content shows a higher degree of enrichment on the resin surface and leads to a higher contact angle against water, while the polysiloxane having optimum compatibility with the epoxy resin shows a greater effect in reducing the static friction coefficient of the resin against glass.

关键词： polysiloxane epoxy resin surface composition friction coefficient

RHEOLOGICAL MODIFICATION OF EPOXY RESINS WITH NANO SILICA PREPARED BY THE SOL-GEL PROCESS

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Chinese Journal of Polymer Science 1999年第3期17卷 253-257页

作者： Xia Wang Jiang Li Cheng-fen Long yun-zhao yu PCLCC Institute of Chemistry, Chinese Academy of Sciences, Beijing 100080, China PCLCC is the Polymer Chemistry Laboratory, Chinese Academy of Sciences and China Petro-Chemica Corporation Chinese Acad Sci Inst Chem PCLCC Beijing 100080 Peoples R China

Nano silica-modified epoxy resins were synthesized by the sol-gel process, The materials have the morphological structure of nano particales dispersed in the epoxy matrix. The dispersed phase formed a physical network in the resin and thus influenced the rheological behavior greatly. However, the nano silica did not show a significant influence on the mechanical properties of the cured resins.

关键词： epoxy resin nano silica mechanical properties rheology sol-gel process

STUDIES　ON　THE　PRENYLFLAVOIDS　PART　Ⅹ　Ⅵ　SYNTHESIS　OF　（±）－3＇，　4＇－METHYLENEDIOXYISODERICINE－A　AND　（±）－PONGAPINONE－B

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Chinese Chemical Letters 1995年第10期6卷 853-854页

作者： Xian Yong BU Lian yun zhao and yu Lin LI(State Key Laboratory of Applied Organic Chemistry, Lanzhou University,Lanzhou 730000)

Methylenedloxyisodericine-A and pongapinone-B were first synthesized via thecondensation of plperonal with 2-hydroxy-4-methoxy-3-prenylactophenone and 4, 6-dimethoxy-2-hydroxy 3-prenylacetophonone respectively follow...

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Study on DNA Cytosine Methylation of Cotton (Gossypium hirsutum L.) Genome and Its Implication for Salt Tolerance

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Agricultural Sciences in China 2010年第6期9卷 783-791页

作者： zhao yun-lei,yu Shu-xun,YE Wu-wei,WANG Hong-mei,WANG Jun-juan and FANG Bao-xing Cotton Research Institute,Chinese Academy of Agricultural Sciences (CAAS)/Key Laboratory of Cotton Genetic Improvement,Ministry of Agriculture,Anyang 455000,P.R.China [a] Cotton Research Institute Chinese Academy of Agricultural Sciences (CAAS)/Key Laboratory of Cotton Genetic Improvement Ministry of Agriculture Anyang 455000 P.R.China

To study the relations between DNA methylation and abiotic stress responses in cotton （Gossypium hirsutum L.）,the methylation-sensitive amplified polymorphism （MSAP） method was used to investigate the differences in methylation level and the change of cytosine methylation patterns under salt （NaCl） stress in two different salt-tolerant cotton *** results showed that the number of the cytosine methylation of CCGG sites in high salt-tolerant cotton line was less than that in low salt-tolerant *** salt stress,extensive cytosine methylation alterations including hypermethylation and demethylation as well as the potential conversion of methylation types occurred in the salt-treated cotton line compared with the corresponding ***,salt stress-induced demethylation loci that occurred in high salt- tolerant cotton line were greater than those in low salt-tolerant cotton line,however,salt stress-induced hypermethylation loci in the high salt-tolerant cotton line were less than those in low salttolerant cotton *** suggested that the demethylation positively contributed to salt tolerance and the hypermethylation had negative effect on salt tolerance in cotton.

关键词： cotton DNA methylation salt stress MSAP methylation polymorphism

Differential Gene Expression Between Hybrids and Their Parents During the Four Crucial Stages of Cotton Growth and Development

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Agricultural Sciences in China 2009年第2期8卷 144-153页

作者： zhao yun-lei, yu Shu-xun, XING Chao-zhu, FAN Shu-li, SONG Mei-zhen and YE Wu-wei Cotton Research Institute, Chinese Academy of Agricultural Sciences(CAAS)/Key Laboratory of Cotton Genetic Improvement, Ministry of Agriculture, Anyang 455000, P.R.China [a]Cotton Research Institute Chinese Academy of Agricultural Sciences (CAAS)/Key Laboratory of Cotton Genetic Improvement Ministry of Agriculture Anyang 455000 P.R. China

The study aims to clarify the differential gene expression between cotton hybrids and their parents in order to better understand the molecular basis of cotton heterosis. The research focused on cotton heterotic and lower heterotic hybrids and their parents during the four crucial stages, which were analyzed using a differential display technique. The results indicated that there were both quantitative and qualitative differences in gene expression amongst them. The quantitative differences include over- and under-expression of parental genes and the dominant expression of highly-expressed parental genes in hybrids. In contrast, the qualitative differences are the following：（i） Bands were observed in both parents but not in the F1 hybrid （BPnF1）; （ii） bands occurred in either of the parents but not in the F1 hybrid （UPnF1）; （iii） bands presented only in the F1 hybrid but not in either of the parents （UF1nP）; and （iv） bands were detected in either of the parents and the F1 hybrid （UPF1）. Overall, the major differences of gene expression occurred in the qualitative level and four related differential patterns were observed. Furthermore, the amount of differential patterns during the flowering stage was relatively higher than those of other stages. At this juncture, both the amount of hybrid-specific expression patterns at flowering stage and the silenced expression patterns at boll-forming stage in highly heterotic hybrids were found higher than those in the lower heterotic ones. It was concluded that significant differences of gene expression in leaves were present between cotton hybrid and its parents during the whole growing stages. Hence, these differences might be responsible for the observed cotton heterosis.

关键词： cotton heterosis molecular mechanism gene expression differential display

“互联网+”时代财经类高校工程管理专业创新人才培养SWOT分析与路径研究

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教育理论与实践 2020年第36期40卷 13-15页

作者：赵华平赵赟钰山西财经大学管理科学与工程学院山西太原030031

"互联网+"时代的创新人才培养是高校的重要任务。通过SWOT方法分析了"互联网+"时代财经类高校工程管理专业人才培养的优劣势和面临的机遇与挑战,结果表明,"互联网+"时代财经类高校工程管理专业创新人才培养要构建以"通工程技术、精管理... 详细信息

"互联网+"时代的创新人才培养是高校的重要任务。通过SWOT方法分析了"互联网+"时代财经类高校工程管理专业人才培养的优劣势和面临的机遇与挑战,结果表明,"互联网+"时代财经类高校工程管理专业创新人才培养要构建以"通工程技术、精管理方法、专数据分析、强风险意识、重社会责任"的新时代中国特色社会主义工程管理专业创新人才为培养目标,以工程项目管理、工程投融资管理、工程咨询与监理等为培养方向,以面向大数据能力培养为工程管理专业课程体系建设重点,线上线下相结合的多元创新教学模式。

关键词： “互联网+” 财经类高校工程管理专业创新人才培养

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骨髓间充质干细胞与角膜损伤修复的研究现状

眼科新进展 2017年第11期37卷 1093-1096页

作者：赵云于莎莎天津市眼科医院天津市眼科学与视觉科学重点实验室天津市眼科研究所天津医科大学眼科临床学院天津市300020

骨髓间充质干细胞是一种主要存在于骨髓中具有自我更新和多向分化潜能的干细胞。目前大量国内外研究证实,骨髓间充质干细胞可以分化为角膜上皮细胞、角膜内皮细胞、角膜缘干细胞,并对眼表损害的修复有重要作用。本文旨在总结骨髓间充质... 详细信息

骨髓间充质干细胞是一种主要存在于骨髓中具有自我更新和多向分化潜能的干细胞。目前大量国内外研究证实,骨髓间充质干细胞可以分化为角膜上皮细胞、角膜内皮细胞、角膜缘干细胞,并对眼表损害的修复有重要作用。本文旨在总结骨髓间充质干细胞在角膜损伤修复的基础研究和临床治疗等方面的研究进展。

关键词：骨髓间充质干细胞角膜分化

肿瘤抑制因子Hamartin和Tuberin信号调控机制

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细胞生物学杂志 2005年第5期27卷 489-492页

作者：赵蕴玉楼丽广中国科学院上海生命科学研究院上海药物研究所上海201203

结节硬化复合症由tsc1、tsc2基因突变引起,这2个基因分别编码hamartin和tuberin,它们均为肿瘤抑制因子,在细胞生长和增殖过程中起关键性的调节作用。生长因子刺激的PI3K/Akt信号通路通过磷酸化tuberin,调控下游效应因子功能,最终影响细... 详细信息

结节硬化复合症由tsc1、tsc2基因突变引起,这2个基因分别编码hamartin和tuberin,它们均为肿瘤抑制因子,在细胞生长和增殖过程中起关键性的调节作用。生长因子刺激的PI3K/Akt信号通路通过磷酸化tuberin,调控下游效应因子功能,最终影响细胞的生长和增殖。现对hamartin和tuberin信号调控机制的最新进展进行综述,并展望其发展趋势。

关键词：肿瘤抑制因子 Hamartin Tuberin 信号调控机制细胞增殖结节硬化复合症