检索结果-南通市图书馆

Synthesis of Two New Chiral Blocks for the Construction of Peptide Nucleic Acid (PNA)

在线全文

学校读者我要写书评

暂无评论

Chinese Chemical Letters 1999年第3期10卷 195-198页

作者： Li Gang ZHANG ji mei min Li He ZHANG(National Laboratory of Natural and Biomimetic Drugs. Bet-ling Medical Unlversity.Beijing 100083) Natl. Lab. Nat. and Biomimetic Drugs Beijing Medical University Beijing 100083 China

Protected (L) and (D)-lysine were used respectively as starting materials to synthesize two new types of chiral blocks for the construction of PNA. Nucleobase was linked to alpha-NH2 of lysine via -CH2C (O)- spacer in... 详细信息

关键词： peptide nucleic acid (PNA) lysine synthesis

Coupling Reaction of 4-Chloro-7-H-Pyrrolo[2,3-d]Pyrimidine with 2,3,5-Tri-O-Acetyl-b-D-Ribofuranosyl Chloride

在线全文

学校读者我要写书评

暂无评论

Chinese Chemical Letters 2001年第5期12卷 391-394页

作者： Yun Long ZHANG Liang Ren ZHANG Zhen Jun YANG ji mei min Li He ZHANG Yang LU Ning Bo GONG Qi Tai ZHENG National Research Laboratory of Natural and Biomimetic Drugs Peking UniversityBeijing 100083 Institue of Materia Medica Chinese Academy of Medical Sciences and Peking Union Medical CollegeBeijing 100050

Coupling reaction of 4-chloro-7-H-pyrrolo[2,3-d]pyrimidine with 2,3,5-tri-O-acetyl -β-D-ribofuranosyl chloride under the basic condition was investigated. An abnormal coupling reaction, in which the heterocyclic base attacked at the carbon of 1,2-O-methylidene moiety instead of anomeric carbon of ribose was observed and the structure of products 5a, 5b were identified by NMR and X-Ray diffraction.

关键词： Chloropyrrolo[2 3-d]pyrimidine 1-chloro-2 3 5-tri-O-acetyl-D-ribofuranose neigh-boring participation effect X-ray diffraction.

Synthesis of Two Nucleotide Derivatives with Phosphate Replaced by Vanadate

在线全文

学校读者我要写书评

暂无评论

Chinese Chemical Letters 1997年第5期8卷 401-402页

作者： De Ping XUE ji mei min Li He ZHANG Kui WANG(Coordination Chedstry Institute,Nanjing University,Nanjing 210008)(National Laboratory of Natural and Biomboic Drug,Beijing Medical University,Beijing 100083) Coordination Chemistry Institute Nanjing University Nanjing 210008 China Natl. Lab. Nat. and Biomimic Drugs Beijing Medical University Beijing 100083 China

Two kinds of vanadyl nucleotide were synthesized from vanadyl trichloride with adenosine derivatives.

关键词： DMSO 亚砜 MHz

STUDIES ON SYNTHESIS OF SUGAR NUCLEOTIDES

在线全文

学校读者我要写书评

暂无评论

Chinese Chemical Letters 1991年第10期2卷 757-760页

作者： Tian Wei MA, ji mei min, Li He ZHANG National Laboratory of Natural and Biomimetic Drugs, Beijing Medical University, Beijing 100083

Glucosyl phosphotriester of adenosine and glucosyl thiophosphotriester of adenosine were synthesized by phosphite-triester methodology.

关键词： STUDIES ON SYNTHESIS OF SUGAR NUCLEOTIDES

通过同源重组在聚球藻7002中表达小鼠金属硫蛋白-Ⅰ的初步研究

在线全文

学校读者我要写书评

暂无评论

生物化学与生物物理进展 2002年第1期29卷 149-153页

作者：周杰罗娜宁叶施定基俞梅敏茹炳根北京大学生命科学学院中国科学院植物研究所北京100093

用PCR方法从海洋单细胞蓝藻聚球藻 70 0 2 (Synechococcussp .PCC 70 0 2 )基因组DNA中扩增得到藻蓝蛋白β亚基基因 (cpcβ)的上游序列 (Pcpcβ) ,及编码谷氨酰胺合成酶的 glnA基因片段 .以Pcpcβ作为启动子、以glnA基因片段作为整合平... 详细信息

用PCR方法从海洋单细胞蓝藻聚球藻 70 0 2 (Synechococcussp .PCC 70 0 2 )基因组DNA中扩增得到藻蓝蛋白β亚基基因 (cpcβ)的上游序列 (Pcpcβ) ,及编码谷氨酰胺合成酶的 glnA基因片段 .以Pcpcβ作为启动子、以glnA基因片段作为整合平台 ,构建含有小鼠金属硫蛋白 Ⅰ (mMT Ⅰ )cDNA的同源整合表达载体 pKGC MT .通过自然转化法将整合表达载体导入聚球藻 70 0 2中 ,经氨苄青霉素筛选 ,得到遗传性状稳定的转基因藻 .PCR检测证明mMT Ⅰ基因已整合到蓝藻基因组DNA上 ;蛋白质印迹表明mMT Ⅰ已在蓝藻中表达 ;ELISA结果显示mMT Ⅰ在蓝藻中的表达量约为 80 0 μg/ g .

关键词：小鼠金属硫蛋白-Ⅰ 启动子Pcpcβ glnA整合平台聚球藻7002 同源重组表达

在线全文

学校读者我要写书评

暂无评论

车用装饰面料的设计与开发

纺织科技进展 2017年第2期 16-18页

作者：李圆周媛吉利梅蔡敏江苏工程职业技术学院江苏南通226006

在针织平针组织的基础上,利用成圈和集圈进行不同规律组合,设计出几何图案,并对织针、三角排列方式及穿纱方式进行上机工艺设计,开发适合车用的纬编单面集圈装饰面料。

关键词：车用针织集圈面料装饰

Synthesis and Crystal Structure of a Three-dimensional (3D) Complex Mn(H_2O)_2(HNic)_2 (HNic=2-Hydroxynicotinic Acid)

在线全文

学校读者我要写书评

暂无评论

Chinese Journal of Structural Chemistry 2006年第5期25卷 572-576页

作者： LI Yu-mei CHE Yun-Xia ZHENG ji-min Department of Chemistry Nankai University Tianjin 300071 China

The title complex Mn（H2O）2（HNic）2 （C22H12MnN2O8, Mr = 367.18） crystallizes in monoclinic, space group P21/c with a = 7.5735（8）, b = 12.5295（13）, c = 7.6466（8）A.β = 101.2790（10）°, Z = 2, V= 711.59（13） A^3, D, = 1.714 g/cm^3,μ（MoKa） = 0.974 mm^-1, F（000） = 374, R1 （1255 observed reflections （Ⅰ 〉 2σ（Ⅰ）） = 0.0250） and wR2 = 0.0662 （all data）. In this paper, we report the complexation of Mn（Ⅱ） by the bidentate ligand 2-hydroxynicotinic acid （HNic）. In the crystal the Mn（Ⅱ） ion exhibits a deformed octahedron structure. The title complex Mn（H2O）2（HNic）2 has a three-dimensional （3D） network structure extended by hydrogen bonds, which are formed by two typical eight-membered hydrogen-bonded rings.

关键词： complex crystal structure three-dimensional network

Robust Correlation Clustering Problem with Locally Bounded Disagreements

在线全文

学校读者我要写书评

暂无评论

Tsinghua Science and Technology 2024年第1期29卷 66-75页

作者： Sai ji min Li mei Liang Zhenning Zhang Institute of Mathematics Hebei University of TechnologyTianjin 300401China School of Mathematics and Statistics Shandong Normal UniversityJinan 250358China College of Statistics and Data Science Beijing University of TechnologyBeijing 100124China Department of Operations Research and Information Engineering Beijing University of TechnologyBeijing 100124China

min-max disagreements are an important generalization of the correlation clustering problem(CorCP).It can be defined as *** a marked complete graph G=(V,E),each edge in the graph is marked by a positive label"+"or a negative label"_"based on the similarity of the connected *** goal is to find a clustering C of vertices V,so as to minimize the number of disagreements at the vertex with the most ***,the disagreements are the positive cut edges and the negative non-cut edges produced by clustering *** paper considers two robust min-max disagreements:min-max disagreements with outliers and min-max disagreements with *** parameter δ∈(0,1/14),we first provide a threshold-based iterative clustering algorithm based on LP-rounding technique,which is a(1/δ,7/(1-14δ))-bi-criteria approximation algorithm for both the min-max disagreements with outliers and the min-max disagreements with outliers on one-sided complete bipartite ***,we verify that the above algorithm can achieve an approximation ratio of 21 for min-max disagreements with penalties when we set parameter δ=1/21.

关键词： min-max disagreements outliers penalties approximation algorithm LP-rounding

Detection of H_2O_2 at a composite film modified electrode with highly dispersed Ag nanoparticles in Nafion

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Chinese Chemical Letters 2011年第4期22卷 458-460页

作者： mei Xiu Kan Xue ji Wang Hui min Zhang School of Science Beijing Institute of TechnologyBeijing 100081China

Ag nanoparticles were prepared by using the ion-exchange of Nafion combined with electrochemical reduction on the electrode. Ag nanoparticles are highly dispersed in Nafion film with an average size of 4.0±0.2 *** amount of Ag nanoparticles can be readily controlled by the amount of Nafion coated on the *** obtained Ag nanoparticles exhibit good catalytic activity for the reduction of H2O2 with a linear response to H2O2 in the concentration range of 0.04-8.0 mmol/L with a sensitivity of 0.34μA/mmol/L and a detection limit of 1.0×10^（-8） mol/L.

关键词： Ag nanoparticles Nafion Electrodeposition Electrocatalytic activity Hydrogen peroxide