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Synthesis of alkyl bis(dimethylamino)methylenecarbamodithioates from 1,1,3,3-tetramethylguanidine,CS_2 and oxiranes

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Chinese Chemical Letters 2012年第6期23卷 699-702页

作者： sima Yavari Samira Nasiri-Gheidari Avat(Arman)Taherpour Issa Yavari Department of Chemistry Arak BranchIslamic Azad UniversityArakIran Department of Chemistry Tarbiat Modares UniversityP.O.Box 14115-175Tehranlran Department of Chemistry Tarbiat Modares UniversityP.O.Box 14115-175TehranIran

An efficient synthesis of alkyl bis（dimethylamino）methylenecarbamodithioates via a one-pot reaction between 1,1,3,3- tetramethylguanidine, carbon disulfide and substituted oxiranes, in good yields, is described.

关键词： Carbamodithioate Oxirane Tetrarnethylguanidine Carbon disulfide One-pot reaction Solvent free

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基于缺陷地慢波传输线结构的液晶移相器设计

空军工程大学学报 2024年第2期25卷 123-127页

作者：李梓玲冯燕司马博羽许恒飞王志诚吴文南京理工大学电子工程与光电技术学院南京210094 南京工程学院信息与通信工程学院南京211167 上海无线电设备研究所上海200438

为了实现低插损、大相位覆盖范围的加载缺陷地结构(DGS)的微带线液晶移相器,利用HFSS仿真软件对DGS微带线液晶移相器进行建模和仿真,通过改变DGS的形状来改变单个移相单元的色散特性,提升单个单元的移相能力,从而减少移相单元的使用数量... 详细信息

为了实现低插损、大相位覆盖范围的加载缺陷地结构(DGS)的微带线液晶移相器,利用HFSS仿真软件对DGS微带线液晶移相器进行建模和仿真,通过改变DGS的形状来改变单个移相单元的色散特性,提升单个单元的移相能力,从而减少移相单元的使用数量,降低移相器传输线整体插损。以哑铃型DGS的液晶微带线移相器作为参考标准,比较了5种形状的DGS(哑铃型、减少DGS面积、一阶分形、三角形、交叉型)的移相能力和插损差异。仿真结果表明:下一阶分形和交叉型DGS微带线液晶移相器移相能力较好,最后对不同介电常数的移相器进行仿具观察其S参数和移相能力,进一步验证了这一结果。

关键词：缺陷地结构液晶移相器色散 S参数

Effects of two strategies on afterglow behavior of Lu_(2)O_(3):Eu single crystal scintillator:Co-doping with Pr^(3+)and solid solution with Sc_(2)O_(3)

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Journal of Rare Earths 2023年第5期41卷 658-665,I0001页

作者： Zhongjun Xue Dongzhou Ding Yating sima Zuyao Zhou Hanrui Dong Shuwen Zhao He Feng School of Materials and Engineering Shanghai UniversityShanghai 200444China Shanghai Institute of Ceramics Chinese Academy of SciencesShanghai 201899China Center of Materials Science and Optoelectronics Engineering University of Chinese Academy of SciencesBeijing 100049China School of Environment and Chemical Engineering Shanghai University of Electric PowerShanghai 201306China

In this paper,effect of two strategies on afterglow behavior of Lu_(2)O_(3):Eu single crystal scintillato r,Pr^(3+)codoping and solid solution with Sc_(2)O_(3),were studied *** groups of Lu_(2)O_(3):5 at%Eu,x at%Pr(x=0,0.2,0.5,1,2 and 5)and(Lu1-yScy)_(2)O_(3):5 at%Eu(y=0,20 at%,50 at%and 70 at%)single crystals were grown by floating zone(FZ)method in air *** structures of as-grown crystals were determined by X-ray diffraction(XRD).The scintillation,photoluminescence properties and carrier trap states were investigated through afterglow,X-ray excitation luminescence(XEL),transmittance,photoluminescence excitation(PLE)and photoluminescence(PL),PL decay and thermal stimulated luminescence(TSL)*** is found that with the increase of Pr^(3+)concentration,the afterglow level of the system decreases at the expense of scintillation luminescence ***,although Sc_(2)O_(3):Eu presents much lower afterglow intensity than Lu_(2)O_(3):Eu,the addition of Sc_(2)O_(3)will just increase the afterglow level of the(Lu1-yScy)_(2)O_(3):5 at%Eu single crystal *** mechanisms for above phenomena are discussed based on experimental results.

关键词： Lu_(2)O_(3):Eu Afterglow behavior Pr3+co-doping (Lu1-yScy)_(2)O_(3)solid solution Rare earths

Characterization of reservoir properties and pore structure based on micro-resistivity imaging logging: Porosity spectrum, permeability spectrum, and equivalent capillary pressure curve

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Petroleum Exploration and Development 2023年第3期50卷 628-637页

作者： TIAN Jie WANG Liang sima Liqiang FANG Shi LIU Hongqi College of Energy Chengdu University of TechnologyChengdu 610059China School of Geosciences&Technology Southwest Petroleum UniversityChengdu 610500China PetroChina Southwest Oil and Gas Field Company Chengdu 610000China

According to the capillary theory,an equivalent capillary model of micro-resistivity imaging logging was *** this basis,the theoretical models of porosity spectrum(Ф_(i)),permeability spectrum(K_(i))and equivalent capillary pressure curve(pe)were established to reflect the reservoir *** promote the application of the theoretical models,the Archie's equation was introduced to establish a general model for quantitatively characterizing bi,K,and *** with the existing models,it is shown that:(1)the existing porosity spectrum model is the same as the general equation of gi;(2)the Ki model can display the permeability spectrum as compared with Purcell's permeability model;(3)the per model is constructed on a theoretical basis and avoids the limitations of existing models that are built only based on the component of porosity spectrum,as compared with the empirical model of capillary pressure *** application in the Permian Maokou Formation of Well TsX in the Central Sichuan paleo-uplift shows that the Ф_(i),K_(i),and p_(ci) models can be effectively applied to the identification of reservoir types,calculation of reservoir properties and pore structure parameters,and evaluation of reservoir heterogeneity.

关键词： micro-resistivity imaging logging pore structure Archie's equation porosity spectrum permeability spectrum capillary pressure curve Sichuan Basin Permian Maokou Formation

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一种过流保护开关及其控制电路的设计

机电元件 2024年第5期44卷 20-23页

作者：司马新仇庆东李鹏周革强沈阳兴华航空电器有限责任公司辽宁沈阳110144 中国航天员科研训练中心北京100094

本文设计了一种用电子电路控制过流保护开关断开的思想,代替了传统双金属发热形变通过机械机构切断电路的方法,使得产品不受温度的影响(双金属片需要温度补偿),且可以控制产品延时断开的时间,达到精准控制电路切换的效果。

关键词：开关过流保护电子电路精确控制

Cloning and Expression Profile of Deoxyhypusine Snyhtase Gene and Deoxyhypusine Hydroxylase Gene in Silkworm, Bombyx mori

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Agricultural Sciences in China 2009年第9期8卷 1120-1129页

作者： WANG Geng-xian sima Yang-hu ZHANG Sheng-xiang XU Shi-qing National Engineering Laboratory of Modern Silk College of Basic Medicine and Biological Sciences Soochow University Suzhou 215123. P.R. China Department of Biological Science Handan Collage Handan 056005 P.R.China College of Forestry Shandong Agricultural University Tai＇an 271018 P.R. China

Deoxyhypusine snyhtase （DHS） and deoxyhypusine hydroxylase （DOHH） are the two enzymes that catalyze the synthesis of hypusine within eukaryotic initiation factor 5A （eIF5A）. Synthesis of hypusine is essential for the function of eIF5A in eukaryotic cell proliferation and survival. Here we described the cloning and expression of two full-length cDNAs, encoding respectively DHS-like protein and DOHH-like protein from Bombyx mori by using the methods of bioinformatics, RACE, and RT-PCR technology, named as BmDHS and BmDOHH. Sequencing results indicate that they are 1 311 and 1 874 bp in length including complete open reading frame （ORF） 1 116 and 915 bp, which encode 371 amino acids （molecular weight is about 41.11 kD and isoelectric point is 5.84） and 304 amino acids （molecular weight is about 34.30 kD and isoelectric point is 4.86）, respectively. BmDHS contains only 1 exon, and BmDOHH contains 4 exons and 3 introns. The deduced amino acid sequence of BmDHS contains a deoxyhypusine synthase domain from 47 to 361 amino acid residues, and the deduced amino acid sequence of BmDOHH contains 6 E-Z type HEAT repeat domains （23-52, 54-83, 87-116, 177-206, 208-237, and 241- 270）. Compared to DHS and DOHH amino acid sequences from other species, such as Homo sapiens and Drosophila melanogaster, both silkworm DHS protein and DOHH protein have more than 55% identity. The conservative regions are very similar with each other. The phylogenetic tree analysis indicated that not only DHS but also DOHH from different species has genus-specific features. The expressions of BmDHS and BmDOHH are no tissue and stage specific in our tested samples.

关键词： Bombyx mori deoxyhypusine snyhtase deoxyhypusine hydroxylase gene cloning gene expression

Smulyan Lemma and Differentiability of the Support Function

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Analysis in Theory and Applications 2018年第4期34卷 348-357页

作者： Ildar Sadeqi sima Hassankhali Department of Mathematics Sahand University of Technology

The purpose of this paper is to verify the Smulyan lemma for the support function, and also the Gateaux differentiability of the support function is studied on its domain. Moreover, we provide a characterization of Fr... 详细信息

关键词： Frechet and Gateaux differentiability support function strict convexity Smulyan lemma

Review of accumulative failure of winding insulation subjected to repetitive impulse voltages

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High Voltage 2019年第1期4卷 1-11页

作者： Potao Sun Wenxia sima Xiongwei Jiang Dingfei Zhang Jiahui He Lian Ye State Key Laboratory of Power Transmission Equipment&System Security and New Technology Chongqing UniversityChongqing 400030People's Republic of China Department of Materials Science College of Engineering MaterialsChongqing UniversityChongqing 400030People's Republic of China Department of Electrical and Computer Engineering University of FloridaGainesvilleFL 32611USA

The premature failure phenomenon that occurs in solid insulation under the application of repetitive impulse voltages is known as the accumulative effect of impulse voltages on a solid *** accumulative failure of winding insulation is considered to be a core problem resulting from this *** main problems include the accumulative failure of motor winding insulation under pulse-width modulation impulses and the accumulative failure of transformer winding insulation under the application of overvoltages,and these problems represent new challenges in the safe and stable operation of power *** regards to the above problems,this study reviews the results of recent research on the accumulative failure characteristics and mechanisms of winding insulation when subjected to repetitive impulse *** challenges faced are discussed at the end of this study.

关键词： insulation winding dielectric

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冯天瑜先生学术思想笔谈

文化软实力研究 2024年第5期9卷 102-122页

作者：马敏罗福惠傅才武司马朝军华中师范大学中国近代史研究所武汉大学国家文化发展研究院上海社会科学院历史研究所

冯天瑜先生是20世纪80年代以来我国著名的历史学学者,先后提出元典分析法、历史文化语义学、中国文化生态论等原创性理论,生前曾出版《“封建”考论》《中华文化史》《中国文化生成史》《周制与秦制》等著作,对中国文化史研究领域具有... 详细信息

冯天瑜先生是20世纪80年代以来我国著名的历史学学者,先后提出元典分析法、历史文化语义学、中国文化生态论等原创性理论,生前曾出版《“封建”考论》《中华文化史》《中国文化生成史》《周制与秦制》等著作,对中国文化史研究领域具有奠基性贡献.本次笔谈从不同角度研读冯天瑜先生生前的著述或遗稿,意在阐释、发扬其学术思想,并缅怀先生.

关键词：冯天瑜中华文化史原创性理论生态论生成史学术思想笔谈