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Synthesis and characterization of poly[(4-vinylphenyl)dimethyl-silane]-b-polybutadiene-b-poly[(4-vinylphenyl)dimethylsilane](PVPDMS-b-PBd-b-PVPDMS)

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Chinese Chemical Letters 2011年第11期22卷 1371-1374页

作者： Hong Wei Ma Bai Wang Chun Qing Zhang Yang Li Yan ming hu yu Rong Wang Liaoning Key Laboratory of Polymer Science and Engineering School of Chemical Engineering Dalian University of Technology Dalian Liaoning 116024 China

The novel functionalized triblock copolymers,poly[（4-vinylphenyl）dimethylsilane]-b-polybutadiene-b-poly[（4-vinylphenyl）-dimethylsilane] （PVPDMS-b-PBd-b-PVPDMS）,were synthesized by anionic polymerization method using high vacuum technique. The hydrocarbon-soluble dilithium initiator synthesized from l,3-di[l-（methylphenyl）ethenyl]benzene（MPEB） was used to synthesize polybutadiene（PBd） precursors and the triblock copolymers in the presence of *** precursors and copolymers were characterized by size exclusion chromatography（SEC）,~1HNMR and DSC techniques.

关键词： Anionic polymerization Functionalized triblock copolymers High vacuum technique

Molecular Identification and Expression Analysis of GhHYDRA1 Gene, a Homologue of HYDRA1 Gene From Upland Cotton (Gossypium hirsutum L.)

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Agricultural Sciences in China 2011年第1期10卷 41-48页

作者： ZANG Zhen-le hu ming-yu LI Xian-bi CHEN Kui-jun LIAO Peng XIAO yue-hua HOU Lei PEI Yanand LUO ming Key Laboratory of Biotechnology and Crop Quality Improvement Ministry of Agriculture/Biotechnology Research Center SouthwestUniversity Chongqing 400716 P.R.China

Beside as precursors of BRs biosynthesis, more and more evidences supported that phytosterols play an important role in plant growth and development. To investigate the effects of phytosterols on the fiber development of upland cotton （Gossypium hirsutum L.） and the molecular base of sterol regulating cotton fiber growth, a homologue of HYDRA1 was cloned from upland cotton （cv. Xuzhou 142） by screening cotton fiber EST database and contigging the candidate ESTs. The GhHYDRA1 encoded a polypeptide of 218 amino acid residues and the deduced amino acid sequences had high homology with the members of HYDRA1 in Populus trichocarpa, Solanum tuberosum, and Arabidopsis thaliana. Moreover, GhHYDRA1 had comparable transmembrane regions to AtHYDRA1 in sequence, length, order, and spacing, except for a C-terminal polylysine cluster. Quantitative real-time RT-PCR analysis revealed that the higher expression levels of GhHYDRA1 gene were detected in 6 to 12 DPA （days post anthesis） fibers, while the lower levels were observed in 0 DPA ovule （with fibers） and 16 to 18 DPA fibers. These results indicated that GhHYDRA1 is the homologue of HYDRA1 gene and plays a crucial role in fiber elongation. Furthermore, auxin and BL up-regulated the expression level of GhHYDRA1 while ABA and KT down-regulated the expression level of GhHYDRA1 in cotton ovule and fiber growth. The result suggested that phytosterols play a role in the interaction of plant hormones.

关键词： cotton fiber phytosterols brassinosteroids GhHYDRA1

Over-expression of GhDWF4 gene improved tomato fruit quality and accelerated fruit ripening

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Journal of Integrative Agriculture 2015年第10期14卷 1980-1991页

作者： YE Shu-e LI Fang LI Xian-bi HONG Qi-bin ZHAI yun-lan hu ming-yu WEI Ting DENG Sha-sha PEI Yan LUO ming Key Laboratory of Biotechnology and Crop Quality Improvement Ministry of Agriculture/Biotechnology Research CenterSouthwest University Citrus Research Institute Chinese Academy of Agricultural Sciences/National Citrus Engineering Research Center

Brassinosteroids（BRs）, a class of steroidal phytohormones are essential for many biological processes in plant. However, little is known about their roles in fruit development. Tomato is a highly valuable vegetable and has been adopted as the model species for studying fruit growth, development, and ripening. To understand the role of endogenous BRs in the development of tomato fruit, the expression patterns of three homologues of DWF4 gene were investigated and the transgenic tomato plants were generated in which the Gh DWF4 gene from upland cotton（Gossypium hirsutum L.） was ectopically expressed. The contents of main quality components were analyzed in fruits of transgenic tomato line and non-transgenic line（control plant, CP） when the fruit was mature. Sl CYP90B3 that possesses high homology with Gh DWF4 preferentially expressed in mature fruit. Significantly higher contents of soluble sugar, soluble proteins, and vitamin C were obtained in fruit of transgenic tomato lines compared with those in the CP. Furthermore, overexpressing Gh DWF4 promoted fruit growth and ripening. The weight per fruit was increased by about 23% in transgenic lines. In addition, overexpressing Gh DWF4 promoted the germination of transgenic tomato seeds and hypocotyl elongation of seedlings. These results indicated that overexpressing Gh DWF4 gene in tomato could increase the contents of many nutrients in fruit and accelerate fruit ripening. It is suggested that increased endogenous BRs in fruit affect the growth and development of tomato fruit and therefore improved the nutrient quality of tomato.

关键词： brassinosteroids Gh DWF4 tomato fruit ripening fruit quality transgenic plant

Cloning and Expression Analysis of a Brassinosteroid Biosynthetic Enzyme Gene,GhDWF1,from Cotton (Gossypium hirsuturm L.)

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Agricultural Sciences in China 2007年第11期6卷 1297-1305页

作者： LUO ming XIAO Zhong-yi XIAO yue-hua LI Xian-bi HOU Lei ZHOU Jian-ping hu ming-yu PEI Yan Key Laboratory of Biotechnology and Crop Quality Improvement Ministry of Agriculture/Biotechnology Research Center SouthwestUniversity Chongqing 400716 P.R.China

Brassinosteroids （BRs） are an important class of plant steroidal hormones that are essential in a wide variety of physiological processes. To determine the effects of BRs on the development of cotton fibers, through screening cotton fiber EST database and contigging the candidate ESTs, a key gene （GhDWF1） involved in the upstream biosynthetic pathway of BRs was cloned from developing fibers of upland cotton （Gossypium hirsutum L.） cv. Xuzhou 142. The full length of the cloned cDNA is 1 849 bp, including a 37 bp 5＇-untranslated region, an ORF of 1 692 bp, and a 120 bp 3＇-untranslated region. The cDNA encodes a polypeptide of 563 amino acid residues with a predicted molecular mass of 65 kD. The deduced amino acid sequence has high homology with the BR biosynthetic enzyme, DWARF1/DIMINUTO, from rice, maize, pea, tomato, and Arabidopsis. Furthermore, the typical conserved structures, such as the transmembrane domain, the FAD- dependent oxidase domain, and the FAD-binding site, are present in the GhDWF1 protein. The Southern blot indicated that the GhDWF1 gene is a single copy in upland cotton genome. RT-PCR analysis revealed that the highest level of GhDWF1 expression was detected in 0 DPA （day post anthesis） ovule （with fibers） while the lowest level was observed in cotyledon. The GhDWF1 gene presents high expression levels in root, young stem, and fiber, especially, at the fiber developmental stage of secondary cell wall accumulation. Moreover, the expression level was higher in ovules （with fibers） of wildtype （Xuzhou 142） than in ovules of fuzzless-lintless mutant at the same developmental stages （0 and 4 DPA）. The results suggest that the GhDWF1 gene plays a crucial role in fiber development.

关键词： cotton DWARF1 gene fiber brassinosteroids phytosterol

Brassinosteroids and Auxin Down-Regulate DELLA Genes in Fiber Initiation and Elongation of Cotton

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Agricultural Sciences in China 2011年第8期10卷 1168-1176页

作者： hu ming-yu LUO ming XIAO yue-hua LI Xian-bi TAN Kun-ling HOU Lei DONG Jing LI De-mou SONG Shui-qing ZHAO Juan ZANG Zhen-le LI Bao-li PEI Yan Key Laboratory of Biotechnology and Crop Quality Improvement Ministry of Agriculture/Biotechnology Research CenterSouthwest UniversityChongqing 400716P.R.China

Plant hormones play important roles in cotton fiber growth and ***,the interaction of phytohormones is largely unknown in fiber cells up to *** proteins are critical component in GA （gibberellic acid） signal transduction,which are also regulated by other phytohormones,such as auxin and *** understand the regulation of DELLA genes in cotton fiber growth and development,we cloned four DELLA genes from upland cotton fibers （Gossypium hirsutum L.）,named GhGAI1,GhGAI2,GhGAI3,and *** of the four predicted proteins with other reported DELLA proteins in various species displayed that they shared conserved domains and high *** profiles of the four GhGAIs in various tissues and organs as well as cotton fibers in different stages displayed that GhGAI1 has higher transcriptional levels than other GhGAIs in all detected ***,the expression level of GhGAI1 was significantly reduced in 0 dpa （day post anthesis） ovules by addition of IAA and epi-BL,and exogenous epi-BL decreased GhGAI1 level in 7 dpa ***,the levels of the other three GhGAIs in 0 dpa ovules and 7 dpa fibers were also regulated by applied *** addition,the levels of GhGAI1 were higher in Xuzhou142 fl mutant （fuzzless-lintless） than in FL （Gossypium hirsutum *** 142） from-1 to 3 dpa ovules,suggesting that GhGAI1 engaged in cotton fiber cell *** results indicated that DELLA genes are involved in the process of fiber cell initiation and elongation regulated by different phytohormones.

关键词： DELLA protein upland cotton cotton fiber development phytohormone

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砂浆碱集料反应细观数值模拟

吉林大学学报（工学版） 2023年第12期53卷 3501-3507页

作者：魏丽丽胡明玉南昌大学工程建设学院南昌330031 赤峰学院资源环境与建筑工程学院内蒙古赤峰024000

由于局部砂浆碱集料现场测试中存在着对上部竖向的压力,为研究砂浆碱集料反应的力学性能,进行了砂浆碱集料反应细观数值模拟。用砂浆棒快速法制备了试样,进行了砂浆试样膨胀率、抗压强度、抗折强度测定;将砂浆试样看作由骨料、界面过渡... 详细信息

由于局部砂浆碱集料现场测试中存在着对上部竖向的压力,为研究砂浆碱集料反应的力学性能,进行了砂浆碱集料反应细观数值模拟。用砂浆棒快速法制备了试样,进行了砂浆试样膨胀率、抗压强度、抗折强度测定;将砂浆试样看作由骨料、界面过渡区(ITZ)和砂浆基体组成的三相复合材料,建立了碱集料反应膨胀模型和碱集料反应强度模型,模拟了不同尺寸规格试样在不同龄期的抗压和抗折性能,解决了砂浆抗压强度和抗折强度较高的问题,仿真结果与测试结果基本一致,证明该模拟仿真具有较好的实用性。

关键词：砂浆碱集料反应细观数值模型力学性能

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排桩支护结构内力与变形三维有限元数值分析

吉林大学学报（工学版） 2016年第2期46卷 445-450页

作者：胡玉明黄音古海东四川大学水利水电学院成都610065 四川盛唐建设工程有限公司成都610042 重庆大学土木工程学院重庆400045 浙江交通规划设计院杭州310006

针对离心模型试验建立了三维有限元数值模型,通过与试验的比较验证了模型的可靠性,并与规范法中的m法进行了比较分析。结合一个悬臂排桩支护结构实例分析了桩身截面尺寸、桩间距和土体强度参数对桩身内力和变形的影响规律。研究表明:采... 详细信息

针对离心模型试验建立了三维有限元数值模型,通过与试验的比较验证了模型的可靠性,并与规范法中的m法进行了比较分析。结合一个悬臂排桩支护结构实例分析了桩身截面尺寸、桩间距和土体强度参数对桩身内力和变形的影响规律。研究表明:采用m法进行排桩支护结构设计偏于保守,与m法相比三维有限元法计算结果与离心机试验结果更为接近;桩身弯矩和桩顶水平位移随桩间净距的增加和桩身截面宽度的减小近似呈线性增加,随着土体黏聚力和内摩擦角的增加近似呈指数形式增加。

关键词：排桩支护离心模型试验三维有限元法

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基于行程多路径的航空公司航班频率优化

交通运输工程学报 2020年第5期20卷 217-226页

作者：乐美龙郑文娟胡钰明南京航空航天大学民航学院江苏南京210016 中国民航工程咨询有限公司北京101300 中南民航空管通信网络科技有限公司广东广州510403

将航空运输网络抽象为多层级网络结构,构建了确定航空公司某一城市对某条路径航班频率的两阶段规划模型:第一阶段从旅客选择行为的角度,考虑旅客对旅行时间、过站时间、计划延误时间、票价等因素的价值感知,构建旅客旅行负效用函数,进... 详细信息

将航空运输网络抽象为多层级网络结构,构建了确定航空公司某一城市对某条路径航班频率的两阶段规划模型:第一阶段从旅客选择行为的角度,考虑旅客对旅行时间、过站时间、计划延误时间、票价等因素的价值感知,构建旅客旅行负效用函数,进而基于多项式Logit模型构建计算旅客选择某个航空公司某个城市对某条路径概率的旅客路径选择模型;第二阶段从航空公司的角度,以总收益最大化为目标函数,基于行程多路径,并考虑航空公司总运力限制,尽可能地让每条路径的运力供给等于需求,构建了确定路径航班频率的线性规划模型;提出了求解两阶段模型的迭代算法。研究结果表明:提出的算法能够在8次迭代之后达到收敛,可以在较短的时间内得到最优解;随着算法的收敛,构建的两阶段规划模型在航线存在市场竞争且整体运力不足的情况下优先将运力安排到收益最高的航线上,提升航空公司整体收益;对于包含多个航节的航线,构建的两阶段模型更能体现旅客选择行为在航班频率配置中发挥的作用;对于包含一个航节的航线,需求随航班频率的变动幅度较小,随着迭代次数的增加,需求航班频率弹性系数逐渐变小,对于包含多个航节的航线,在航线总需求一定的情况下,需求随航班频率的变动幅度较大,由于市场竞争存在航班频率不变需求骤减的情形。可见,所提出的模型和算法能够有效提升航空公司收益。

关键词：航空运输航班频率优化路径选择多层级网络迭代算法航节

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鬼像影响下的调制传递函数计算模型

中国光学（中英文） 2024年第5期17卷 1183-1191页

作者：肖鹏益刘铭鑫闫磊胡铭钰张新中国科学院长春光学精密机械与物理研究所吉林长春130033 中国科学院大学北京100049

为了探究鬼像对成像系统性能的影响,构建了二次反射产生的鬼像影响下的调制传递函数(MTF)的计算模型。本文首先介绍了在近轴近似下的鬼像分析与描述的方法。接着,从调制传递函数的定义出发,考虑鬼像在像面处的照度对像面调制度的影响,... 详细信息

为了探究鬼像对成像系统性能的影响,构建了二次反射产生的鬼像影响下的调制传递函数(MTF)的计算模型。本文首先介绍了在近轴近似下的鬼像分析与描述的方法。接着,从调制传递函数的定义出发,考虑鬼像在像面处的照度对像面调制度的影响,构建了鬼像影响下的MTF计算模型。通过对一系统进行实例计算,并与仿真结果进行对比,均方误差最大不超过0.049373,进而验证了该模型的准确性。同时针对误差较大的结果进行了详细分析,明确了该计算方法的适用范围。研究结果表明,利用近轴近似的方法计算鬼像影响下的MTF在大多数情况下是真实准确的,该研究在光学系统的鬼像分析方面做出了有益探索。

关键词：近轴近似杂散光分析鬼像调制传递函数

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