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“有效降低全社会物流成本”研讨会专家观点综述

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中国流通经济 2024年第5期38卷 3-17页

作者：本刊编辑部《中国流通经济》编辑部

2024年2月24日,习近平总书记主持召开中央财经委员会第四次会议,指出物流是实体经济的“筋络”,强调必须有效降低全社会物流成本,增强产业核心竞争力,提高经济运行效率。基于此,2024年4月24日,北京物资学院党委宣传部、杂志社、科研处... 详细信息

2024年2月24日,习近平总书记主持召开中央财经委员会第四次会议,指出物流是实体经济的“筋络”,强调必须有效降低全社会物流成本,增强产业核心竞争力,提高经济运行效率。基于此,2024年4月24日,北京物资学院党委宣传部、杂志社、科研处联合主办了“有效降低全社会物流成本”研讨会。本次研讨会邀请我国流通物流领域的专家学者,围绕物流服务实体经济和人民群众、物流成本构成、交通运输体系改革、统一高效物流市场构建和现代商贸流通体系完善等问题,发表观点,为探索有效降低全社会物流成本可行路径,构建现代流通体系提供理论支持和实践指导。本刊编辑部对专家阐述的主要观点进行了归纳整理,以飨读者。

关键词：全社会社会物流成本新质生产力流通体系降本增效

Hemin-mediated Hemolysis in Erythrocytes:Effects of Ascorbic Acid and Glutathione

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Acta Biochimica et Biophysica Sinica 2006年第1期38卷 63-69页

作者： Shu-De LI~(1,2),Yan-Dan SU~3.Ming LI~1,and Cheng-Gang ZOU~(1*) ~1 School of Life Sciences,Yunnan university,Kunming 650091,china ~2 department of Bio{3. and~3.department of Clinical {3.,Kunming Medical College.Kunming 65003.,china School of Life Sciences Yunnan University Kunming 650091 China department of Biochemistry Kunming Medical College Kunming 650031 China department of Clinical chemistry Kunming Medical College Kunming 650031 China

In the present work,we investigated the effect of ascorbic acid and glutathione on hemolysisinduced by hemin in *** acid not only enhanced hemolysis,but also induced formationof thiobarbituric acid-reactive substances in the presence of *** has been shown that glutathioneinhibits hemin-induced hemolysis by mediating hemin *** depleted of glutathionebecame very sensitive to oxidative stress induced by hemin and ascorbic acid.H2O2was involved in hemin-mediated hemolysis in the presence of ascorbic ***,a combination of glutathione and ascorbicacid was more effective in inhibiting hemolysis induced by hemin than glutathione *** andintracellular ascorbic acid exhibited a similar effect on hemin-induced hemolysis or inhibition of hemin-induced hemolysis by *** current study indicates that ascorbic acid might function as anantioxidant or prooxidant in hemin-mediated hemolysis,depending on whether glutathione is available.

关键词： erythrocyte ascorbic acid hemin glutathione H2O2

Synthesis and Characterization of One-dimensional and Two-Dimensional Porphyrin Polymers (Ⅰ)

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Chemical Research in Chinese Universities 2001年第2期17卷 226-227页

作者： LI Xiang-qing, WANG Xing-qiao, GUO Jing-fu, MENG He and LJU Guo-fa (department of chemistry, jilin {3., Changchun 13.023. P. R. china) 吉林大学吉林长春 130023

A procedure for the synthesis of one-dimensional tetraaminophenylporphyrin (TAPP) was described. Quantitative infrared (IR) spectrum analysis of the monomer showed that it exhibited strong absorption at 1,621 cm-1. Results also indicated that the interaction between porphyrin macrocycles was enhanced after the metalloporphyrin linked up with the axial ligand. The degree of polymerization in [Mn(TPP)(pyz)]n was assessed using the ligand absorption rate.

关键词： Synthesis Porphyrin polymer Bipyridine Imidazole

Distinguishing malignant from normal stomach tissues and its in vivo, in situ measurement in operating process using FTIR Fiber-Optic techniques

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Science china chemistry 2005年第2期48卷 167-175页

作者： XU Yizhuang1, YANG Limin1, XU Zhi3. ZHAO Ying2, LING Xiaofeng3. LI Qingbo1, WANG Jiansheng4, ZHANG Nengwei3. ZHANG Yuanfu1 & WU Jinguang1 1. The State Key Laboratory of Rare Earth Materials and Applications, College of chemistry and Molecular Engineering, Peking university, Beijing 100871, china 2. Institute of chemistry, Chinese Academy of Sciences, Beijing 100080, china 3. department of Surgery, Third Hospital, Peking university, Beijing 100083. china 4. department of Oncology Surgery, the First Hospital of Xi’an Jiaotong university, Xi’an 710061, china Correspondence should be addressed to Wu Jinguang (email: wujg@***) The State Key Laboratory of Rare Earth Materials and Applications College of Chemistry and Molecular Engineering Peking University Beijing China department of Surgery Third Hospital Peking University Beijing China Institute of chemistry Chinese Academy of Sciences Beijing China department of Oncology Surgery the First Hospital of Xi’an Jiaotong University Xi’an China

Gastric tissue samples were studied using mid-IR fiber-optic attenuated total reflectance (ATR) spectroscopy. FTIR spectra of 90 tissue samples from 48 patients, including 3. normal and 58 malignant tissue samples, were chosen as examples. Malignancy was usually characterized by the absence of CH and C=O bands, a weak amide II band near 1545 cm-1, a shift of the amide I band to lower wave number, a decrease in the ～1450 cm-1 peak to less than the～1400 cm-1 peak. Subtraction spectra indicate that the amide I and amide II bands of normal and malignant tissues have larger differences in peak positions and relative intensities. The statistical analysis results confirm this conclusion. The results indicate that FTIR fiber optic techniques provide important information about cancerous tissue of the stomach, which can be used to differentiate the malignant tissue from the normal tissue. Based on the above results we successfully realize the detection of the tumor tissues of digestive tract in vivo and in situ. And the results of detection cancer near operating room and in vivo and in situ in the operating room are consistent with the conclusions for the samples stored in liquid N2, which is the basis for the clinical application.

关键词： FTIR, Fiber-Optics, stomach tissues, cancer, diagnosis.

On the periodic solutions of a type of differential-iterative equations

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Chinese Science Bulletin 1998年第3期43卷 204-206页

作者： GE Weigao 1, LIU Zhengrong 2 and YU Yuanhong 3.1. department of Applied Mathematics, Beijing Institute of Technology, Beijing 100081, china 2. department of Mathematics, Yunnan {3., Kunming 650091, china 3. Institute of Applied Mathematics, C department of Applied Mathematics Beijing Institute of Technology Beijing China department of Mathematics Yunnan University Kunming China Institute of Applied Mathematics Chinese Academy of Sciences Beijing China

Sufficient conditions for the existence of periodic solutions to a type of nonautonomous differential_iterative equations are given.

关键词： differential_iterative equation periodic solution fixed point.

SYNTHESIS AND BIOTECHNOLOGICAL APPLICATIONS OF VINYL POLYMERINORGANIC HYBRID AND MESOPOROUS MATERIALS

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Chinese Journal of Polymer Science 2000年第1期18卷 1-7页

作者： Yen Wei Kun-yuan Qiu department of chemistry, Drexel university, Philadelphia, Pennsylvania 19104, USA department of Polymer Science and Engineering, Peking university, Beijing 100871, china Drexel university 美国北京大学高分子科学与工程系北京

We describe the sol-gel synthesis of a new family of organic-inorganic hybrid materials, in which various vinyl polymers are covalently bonded to and uniformly distributed in inorganic oxide matrices. The materials can be tailored to have both good toughness and hardness while maintaining excellent optical transparency. Doping the sol-gel metal oxides with optically active compounds such as D-glucose results in new optical rotatory composite materials. Removal of the dopant compounds from the composites affords mesoporous oxide materials; which represents a new, nonsurfactant-templated route to mesoporous molecular sieves. We have successfully immobilized a series of enzymes and other bioactive agents in mesoporous materials. Catalytical activities of the enzyme encapsulated in mesoporous materials were found to be much higher than those encapsulated in microporous materials.

关键词： vinyl polymer-inorganic hybrid materials mesoporous materials sol-gel process biotech-nological applications

Molecular dynamics simulations on the structures and properties of ε-CL-20-based PBXs ——Primary theoretical studies on HEDM formulation design

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Science china chemistry 2007年第6期50卷 737-745页

作者： XU XiaoJuan1,2, XIAO JiJun1, HUANG Hui3. LI JinShan3.& XIAO HeMing1 1 department of chemistry, Nanjing university of Science and Technology, Nanjing 210094,{3. 2 department of chemistry, Yancheng Teacher’s College, Yancheng 224002,{3. 3.Institute of Chemical Materials,{3. Academy of Engineering Physics, Mianyang 621900,{3. department of chemistry Nanjing University of Science and Technology Nanjing China department of chemistry Yancheng Teacher’s College Yancheng China Institute of Chemical Materials China Academy of Engineering Physics Mianyang China

Five polymer bonded explosives(PBXs)with the base explosive epsilon-CL-20(hexanitrohexaazaisowurtzi-tane),the most important high energy density compound(HEDC),and five polymer binders(Estane 5703.GAP,HTPB,PEG,and F_(23.4))were *** dynamics(MD)method was employed to investigate their binding energies(E_(bind))3.≈ epsilon-CL-20/GAP 3.4).By pair correlation function g(r)analyses,hydrogen bonds and vdw are found to be the main interactions between the two *** elasticity and isotropy of PBXs based epsilon-CL-20 can be obviously improved more than pure epsilon-CL-20 *** is not by changing the molecular structures of epsilon-CL-20 for each binder to affect the *** safety and energetic properties of these PBXs are mainly influenced by the thermal capability(C_p^(deg))and density(p)of binders,respectively.

关键词： high energy density material (HEDM), hexanitrohexaazaisowurtzitane (CL-20), polymer bonded explosives (PBXs), molecular dynamics (MD), compatibility, safety properties, mechanical properties, energetic properties

SYNTHESIS OF NOVEL SOLUBLE AROMATIC POLYPYROMELLITIMIDE CONTAINING ORDERED 1,2,4-TRIAZINE IN THE MAIN CHAIN

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Chinese Journal of Polymer Science 2002年第3期20卷 219-224页

作者： Xiao-bing Yi Guo-shi Wu Feng-cai Lu department of chemistry Tsinghua university, Beijing 100084{3. Institute of chemistry Chinese Academy of Sciences, Beijing 100080,{3. department of chemistry Tsinghua University 北京 100084 Institute of chemistry Chinese Academy of Sciences 北京 100080

A new heat-resistant, soluble polymer, poly(phenyl-1,2,4-triazine imide), has been prepared via a two-step method of polycondensation of N,N'-bis(4-benzil)pyromellitimide and terephthalamidrazone in cresol, followed by curing at higher temperature. The rigid 1,2,4-triazine group increases the solubility of the polyimide so that the polymer is soluble in cresol, N-methyl-2-pyrrolidone (NMP), trifluoroacetic acid and concentrated sulfuric acid, etc. Thermogravimetric analysis (TGA) indicates that this novel polyimide has good thermal stability with a high decomposition temperature of 447degreesC in air and of 423.degreesC in N-2, It has a tensile strength of 107.4 MI'a with an elongation at break of around 7.6%.

关键词： polyimides N,N '-bis(4-benzil)pyromellitimide rigid-rod group 1,2,4-triazine

PROPERTIES AND SYNTHESIS OF NEW SUPPORTS FOR IMMOBILIZATION OF ENZYMES BY COPOLYMERIZATION OF VINYLENE CARBONATE AND METHACRYLIC ACID

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Chinese Journal of Polymer Science 2000年第4期18卷 343-349页

作者： Lun-han Ding Yue Li Yan Jiang Zhe Cao Jia-xian Huang department of Polymer Science and Engineering, university of Science and Technology of china, Hefei 23.026, china department of chemistry, Nankai university, Tianjin 3.0071, china 中国科学技术大学安徽合肥南开大学天津

Methacrylic acid first was neutralized with an aqueous solution of NaOH to pH = 6.0 similar to 7.0, vinylene carbonate (VCA) was added to the solution, then monomers were copolymerized in paraffin oil by means of reverse-phase suspension polymerization and hydrophilic copolymeric supports were prepared. The properties of the supports were determined using trypsin and results show that the amount of enzymes coupled to the supports and the specific activity of immobilized trypsin are related to the content of VCA structure units, reaction time and concentration of enzyme solution, etc.

关键词： vinylene carbonate methacrylic acid fixed enzyme support trypsin