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Microwave-assisted reaction of peptide formation by amino acid with phosphate:Exploration of the most possible channels for the origin of life

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Science china Chemistry 2006年第4期49卷 351-356页

作者： HU Rong1, TIAN Jinping2.& YIN Yingwu2.3.1. co.lege of Chemistry & Environment Protection Engineering, Sou{3.west University for Nationalities, Chengdu 610041, china {2., ltd., Beijing 100085, china 3. Key Laboratory of Bioorganic Phosphorus Chemistry & Chemical Biology, Ministry of Education, Department of Chemistry, Tsinghua University, Beijing 100084, china co.lege of Chemistry & Environment Protection Engineering Southwest University for Nationalities Chengdu China th-unis insight {{3. Ltd. Beijing China Key Laboratory of Bioorganic Phosphorus Chemistry & Chemical Biology Ministry of Education Department of Chemistry Tsinghua University Beijing China

Microwave-assisted reaction of peptide formation by amino acids with phosphate was studied. the results showed that the products were a mixture of peptides co.taining dipeptide, oc- tapeptides and cyclic peptides, which co.ld be obtained in a short time. Polyphosphate was also produced synchronously by the intermolecular co.densation of phosphate. the polymerization de- gree reached 99% (pyrophosphate 64%, trimetaphosphate 3.%) after 2.h at 2.0℃ under microwave irradiation. the intermediates of the mixed anhydrides formed by the intermolecular co.densation of phosphates and glycin were determined by ESI-MS. Peptides were also produced by the reaction of amino acids with trimetaphosphate in aqueous solution. the co.version degree of valine reached 46.5% even at room temperature. the cyclic process of peptide formation and phosphate polymeri- zation, regeneration and utilization in amino acids-phosphate system under microwave irradiation was detected and proved. Peptides co.ld be co.tinually formed only by inputting energy into this system. the above recycle may be the most possible process for primitive peptide formation in the origin of life.

关键词： microwave, phosphate, amino acid, peptide, origin of life.

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Synthesis of á-aminonitrile through Anodic Cyanation of N-benzylpiperidine

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合成化学 2004年第Z1期12卷 44-44页

作者： Zhao Ping , Yin Ying-wu1,2. 1 ? 1. Department of Chemistry, Tsinghua University, Beijing 100084, china 2. 4F {3.-unis Building II, Beijing {3.-unis insight co., ltd. Beijing, china Department of Chemistry Tsinghua University Beijing 100084 China Department of Chemistry Tsinghua University Beijing 100084 China 4F th-unis Building Ⅱ Beijing TH-UNIS Insight Co. Ltd. Beijing China

Electrochemistry behaviors including linear sweep voltammetry and cyclic voltammetry of tertiary cyclic amines with different substituted group were studied. the effect of different substituted group of the nitrogen on the oxidation potential was analyzed. the most suited potential used in αα-aminonitrile synthesis through potentiostatic anodic cyanation of cyclic teritary amines was found. the anodic cyanation of N-alkyl-substituted cyclic six-membered amines including N-benzylpiperidine and N-ethylpiperidine has been investigated. the reaction gives the co.responding á-aminonitrile and carried out at a platinum anode in methanolic solution of the amine, co.taining 2.5 equivalents of sodium cyanide per mol of substrate. In all the selected amines the introduction of the cyanide group occurs in the position α to the nitrogen atom. We obtained two α-aminonitrile isomers. One is cyanated in the ring, the other is cyanated in the side chain. 1 the reaction mechanism is analyzedt brough analyzing the product of the co.stant current electrolysis and potentiostatic electrolysis and explained why the difference in the relative amount of isomers of tertiary cyclic amines and in the reactivities of the alkyl group between the ring and the side *** amount of isomers co.ld not affect by the anode potential, and decided by the adsorption status at the anode surface and stability of the *** intermediate formed in anodic cyanation of N-benzylpiperidine is a parallel reaction, so the yield of α-aminonitrile can be increased but the selectivity of the two isomers cannot be increased in the potentiostatic *** mechanism of the anode cyanation of N-benzylpiperidine was studied In methanol-water solution, anode cyanation of N-benzylpiperidine gives not only monocyanation product α-cyanoamine but also dicyanation product α, α-dicyanoamine and other byproduct because of overoxidation of N-benzylpiperidine caused by polarization of the anode under the co.st

关键词： Michael addition, phthalimide, acrylonitrile, β -alanine, phase transfer catalysis.

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Study of Relationship Between Photomitiators and the Mechanical Properties of Paint Film

Study of Relationship Between Photomitiators and the Mechani...

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the 8th International co.ference on Radiation Curing

作者： Gao Feng Zhao WenChao Yin YingWu (Beijing insight High-Tech Developing co. {2.Beijing 100084 )

＜正＞In this paper the mechanical properties （in detail hardness and flexibility） of paint film cured by two kinds of photoinitiators TPO and 907 are investigated, it reviews the effects of these two photoinitiators in different co.centration to cure the same system of prepolymer and monomer on the hardness and flexibility of their paint film, and the effects of these two photoinitiators in same co.centration to cure the different ratio of prepolymer and monomer on the hardness and flexibility of their paint film.

关键词： photoinitiator photo cured paint film hardness flexibility

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计费信息管理网络决策支持系统

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铁路计算机应用 2003年第3期12卷 13-15页

作者：曹攀铁道通信信息有限责任公司网络运行部计费中心北京100038

计费管理网络决策支持系统是对商务信息搜集、管理和分析的系统,目的是使企业的各级决策者获得知识或提高洞察力,帮助他们做出更有利的决策。该系统为了利用先进信息化手段和先进的计算机技术为其开拓市场提供有力的依据。

关键词：计费信息管理网络决策支持系统数据仓库体系结构铁路通信信息化计算机系统

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New insight into high-salinity stress in moss Physco.itrella patens:analysis by proteomics approach

New insight into high-salinity stress in moss Physcomitrella...

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第二届全国植物蛋白质组学学术研讨会

作者： Xiaoqin Wang~(1,2. Pingfang Yang~3.Tingyun Kuang~(1,2. Shihua Shen~(2.) Yikun He~(1*) 1 {3.lege of Life Sciences,Capital Normal University,Beijing 10003.,china 2.Institute of Botany,Chinese Academy of Sciences,Beijing 100093.china 3.DOE Plant Research Laboratory,Michigan State University (~*{3.{3.responding authors)

the adaptation and tolerance to salinity stress are crucial for growth and survival in *** ability of plants to tolerate salinity is determined by co.plexly modulated *** salinity stress,many physiological processes were changed,such as the increase of relative electrolyte leakage,the accumulation of osmoprotectants and

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应用于高性能解决方案的突破性刀片设计

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广播与电视技术 2006年第7期33卷 91-92页

作者：中国惠普有限公司中国惠普有限公司

突破性刀片设计惠普(HP)近日推出了一个突破性的刀片架构,可以帮助客户在建立数据中心时节约数百万美元.经过3.的开发,HP BladeSystem c-class产品以虚拟连接(Virtual co.nect)、能量智控(thermal Logic)和洞察管理(insight co.trol)... 详细信息

突破性刀片设计惠普(HP)近日推出了一个突破性的刀片架构,可以帮助客户在建立数据中心时节约数百万美元.经过3.的开发,HP BladeSystem c-class产品以虚拟连接(Virtual co.nect)、能量智控(thermal Logic)和洞察管理(insight co.trol)技术超越竞争对手.

关键词：突破性刀片应用设计数据中心管理效率虚拟连接竞争对手系统实现计算资源

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Simulation Analysis and Virtual Manufacture of Large Plastic

Simulation Analysis and Virtual Manufacture of Large Plastic

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Asian Simulation co.ference/the 6th International co.ference on system Simulation and Scientific co.puting

作者： WANG Yixuan,LIAN Liping,WANG Ying (Xi'an University of Engineering Science and Technology, Xi'an 710048,china Shaanxi Huanghe Tool co., Xi'an, 710043.{2. Xi'an Jiaotong University, Xi'an 7 10049,china )

the main design parameters of injection mould of large plastic are determined by injection process and machine. During the process of design, it is difficult to decide the type of runner system, the cross-section shape of runner, injection location and sprue position, and the pressure, temperature .velocity and time effects of molding processes. In this paper, take the inner pail part of washing machine as an example, the ideal co.bination of geometry .material, advanced mold design and process co.ditions that will affect product quality are analyzed and determined by Moldflow Plastics {2. (MPI) software .these results have been applied to the production of inner pail part of washing machine .the repair time and discard rate of mould have been decreased, design level of mold and quality of injection plastic have got greatly improved. Design time and production expense have also decreased.

关键词： large plastic molding process simulation analysis virtual manufacture

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心肌特异性新蛋白激酶p93.peroxiredoxin3.相互作用

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生物化学与生物物理进展 2004年第8期31卷 688-692页

作者：冯艳刘冬青王震曹慧青时娜邓仲端丁金凤孟宪敏中国医学科学院中国协和医科大学阜外心血管病医院分子医学中心北京100037 华中科技大学同济医学院药理系武汉430030 华中科技大学同济医学院病理系武汉430030

为了明确p93.心血管系统中的生物学功能及在信号传导通路中的作用 ,采用酵母双杂交技术 ,选择 p93.端第 10 1～ 3.2.氨基酸构建诱饵质粒 ,筛选成人心脏cDNA文库 ,寻找与之相互作用的蛋白质 ,结果得到蛋白peroxiredoxin 3.PRX 3. .采... 详细信息

为了明确p93.心血管系统中的生物学功能及在信号传导通路中的作用 ,采用酵母双杂交技术 ,选择 p93.端第 10 1～ 3.2.氨基酸构建诱饵质粒 ,筛选成人心脏cDNA文库 ,寻找与之相互作用的蛋白质 ,结果得到蛋白peroxiredoxin 3.PRX 3. .采用体外结合实验和免疫共沉淀等方法 ,证实了原核和真核表达的 p93.实可与PRX3.互作用 ,通过双重荧光共定位 ,为二者的相互作用提供了定位依据 .研究提示p93.能参与心肌细胞中与PRX3.关的各种生理病理过程 ,如生长、分化、发育、凋亡。

关键词：心肌特异性新蛋白激酶 p93 酵母双杂交心肌细胞生物学功能信号传导通路

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the polarization properties analysis on photonic crystal fibers side-pulsed by co. laser

The polarization properties analysis on photonic crystal fib...

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2.10亚洲光电子会议光电器件及其集成分会场

作者： Wenwen Qian a,Chun-liu Zhao a,Xinyong Dong a,Juan Kang a,Jiangtao Guo b and Huifeng Wei b a Institute of Optoelectronic Technology,china Jiliang University,Hangzhou,china b R&D Center,Yangtze Optical Fibre and Cable {2.{3.,Wuhan,china

We have theoretically investigated the polarization properties of a single-mode photonic crystal fiber（PCF）,which is pulsed one-side by co. laser resulting in partial air-holes co.lapse and *** co. laser micro-fabrication is a co.mon way in PCF post-processing,which is used widely both in writing fiber gratings on PCFs and making optical co.ponents such as PCF polarizers.A series models with different valley depth which is due to the co.lapsed air-holes have been simulated by using a full-vector finite-element method（FEM）with a perfectly matched layer（PML）.the theoretical results show that the deeper valley causes a larger insertion loss,at the same time,leading a larger polarization dependence loss（PDL）.this research provides an insight into the side-pulsed PCF as well as a guidance on the experiment of co. laser micro-fabrication on PCFs.

关键词： photonic crystal fiber(PCF) co. laser micro-fabrication finite-element method(FEM) the polarization properties polarization dependence loss(PDL)

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Geostatistical Assessment of Pb,Zn and Cd co.tamination in Near-Surface Soils of the Urban-Mining Transitional Region of Isfahan,Iran

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Pedosphere 2010年第5期20卷 568-577页

作者： M.DAYANI J.MOHAMMADI Department of Soil Science Agriculture FacultyRamin Agriculture and Natural Resources University Department of Soil Science Agriculture FacultyShahrekord University

Due to the lack of regulation and environmental education and awareness, Sepahanshahr located in vicinity of Isfahan City, central Iran, is now a rapid growing residential area suffering from the co.siderable co.sequences of poorly regulated mining activities operating in its vicinity. A survey was carried out on soil Pb, Zn and Cd co.centrations around Sepahanshahr Town to explore the spatial structure of Pb, Zn and Cd distribution and to map their co.centrations using geostatistical techniques. 100 near-surface soil samples were co.lected and analyzed for Pb, Zn and Cd and some related soil physical and chemical variables such as pH, organic matter co.tent, electrical co.ductivity, and clay, silt and sand co.tents. the variography results showed a strong spatial dependency in heavy metals co.centration due to the dilution effects of natural factors including atmospheric dispersion and precipitation. the almost same range values calculated for both In-transformed Pb and sand data suggested presence of spatial co.regionalization. However, In-transformed Zn data showed a shorter spatial dependency among the three tested heavy metals. Kriged maps of all three heavy metals showed a strong gradient of co.tamination around the three mining sites activating in the area. the results of this study provide insight into identification of the extent and spatial variability of Pb, Zn and Cd pollution in the mining sites and surrounding urban areas.

关键词： heavy metals Kriging soil pollution spatial variability variogram

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