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A universal strategy for fast,scalable,and aqueous synthesis of multicomponent palladium alloy ultrathin nanowires

Science China Chemistry 2021年第2期64卷 245-252页

作者： Hao Lv xuwen guo Lizhi Sun Dongdong Xu Ben Liu College of Chemistry Sichuan UniversityChengdu 610064China Jiangsu Key Laboratory of New Power Batteries Jiangsu Collaborative Innovation Center of Biomedical Functional MaterialsSchool of Chemistry and Materials ScienceNanjing Normal UniversityNanjing 210023China

Noble metal alloy nanowires(NWs)with ultrathin diameters(2–3 nm)and precisely controllable elemental compositions have attracted dramatically growing attention for(electro)*** numerous achievements in past two decades,noble metal alloy NWs are mostly synthesized with the traditional oil-phase methods that suffer from some undesirable ***,we report a general strategy for fast,scalable,and aqueous synthesis of multicomponent Pd-based alloy ultrathin NWs with an average diameter of 2.6 nm,ranging from bimetallic PdM(PdFe,PdCo,PdNi,PdCu,PdZn,PdRu,PdRh,PdAg,PdCd,PdIr,PdPt,PdAu)and binary PdS/PdP NWs,to trimetallic PdM1M2 NWs(PdAuCu,PdCoNi,PdCuZn,PdCuNi,PdAgCu,PdAuCu,PdRuAg,PdAuRu,and PdPtAu),and to tetrametallic PdM1M2M3 NWs(PdAuAgCu,PdCoCuNi,PdAuCuNi,PdPtAuCu,and PdIrPtAu).The key to the success of this aqueous synthesis is the utilization of N2H4 as the extremely strong reducing agent that directs the synchronous reduction and anisotropic nucleation growth of multicomponent Pd alloy NWs along nanoconfined columnar phase assembled with amphiphilic dioctadecyldimethylammonium ***-resultant Pd-based alloy ultrathin NWs exhibit multiple structural and compositional synergies,which remarkably optimize the removal of poisoning ethoxy intermediates and thus improve electrocatalytic performance towards ethanol oxidation reaction(EOR).Among them,tetrametallic PdAuCuNi alloy ultrathin NWs hold a high EOR activity of 5.14 A mg-1 Pd and a low activation energy of 13.1 kJ mol^-1,both of which are much better than its counterpart catalysts alloyed with less *** work represents an important advance in precise aqueous synthesis of multicomponent noble metal alloy ultrathin NWs as the high-performance electrocatalysts for various targeted applications.

关键词： ultrathin nanowires multicomponent alloys palladium synthetic chemistry ethanol oxidation reaction

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Analysis on Network Security and Solution of Computer

Analysis on Network Security and Solution of Computer

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International Conference on Information Science, Automation and Material System

作者： Dong, Yahui Li, Wei guo, xuwen Henan Inst Sci & Technol Sch Econ & Management Xinxiang 453003 Peoples R China

ISBN: (纸本)9783037850817

Currently, the issue of computer network security becomes more and more serious. This thesis takes the main factors that affect the computer network security as the breakthrough, and pays attention to the analysis and prevention of various measures that are not conducive to the normal operation of computer network. It also fully discusses the situations that affect the computer network security from different perspectives in order to take preventive measures, remove adverse factors in the embryonic stage and ensure the security management and effective operation of computer network. This thesis proposes solutions from seven aspects, namely security and encryption technology, firewall technology, network address translator technology, security kernel technology of operating system, technology of anti virus in computer network, network backup system and security management.

关键词： computer network system security network permission encode

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A Study on the Security Issues and Solution of Electronic Commerce

A Study on the Security Issues and Solution of Electronic Co...

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International Conference on Information Science, Automation and Material System

作者： Dong, Yahui Li, Wei guo, xuwen Henan Inst Sci & Technol Sch Econ & Management Xinxiang 453003 Peoples R China

ISBN: (纸本)9783037850817

As a new business model, e-commerce has great prospects for development. Meanwhile, such an e-business model has put forward higher requirements for the management level and the technology of transmitting information, and the construction of security system is particularly important. How to create a safe and convenient application environment for e-commerce, and providing adequate protection of information are the issues concerned by companies and users. Firstly, this thesis puts forward the existing safety risks of e-commerce in China. Then, their causes are analyzed. Finally, the relevant conclusions are drawn from the perspective of technology, legal, security management and network morality.

关键词： Electronic Commerce Internet Security

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Strategies on the Implementation of China's Logistics Information Network 1

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International Conference on Advanced Research on Electronic Commerce, Web Application, and Communication

作者： Dong, Yahui Li, Wei guo, xuwen Henan Inst Sci & Technol Sch Econ & Management Xinxiang 453003 Peoples R China

ISBN: (数字)9783642203701

ISBN: (纸本)9783642203695

The economic globalization and trend of e-commerce network have determined that the logistics industry will be rapidly developed in the 21st century. In order to achieve the optimal allocation of resources, a worldwide rapid and sound customer service system should be established. The establishment of a corresponding modern logistics system is the inevitable choice of this requirement. It is also the inevitable choice for the development of modern logistics industry in China. The perfect combination of modern logistics and information network can better promote the development of the logistics industry. Through the analysis of Status of Logistics Industry in China, this paper summed up the domestic logistics enterprise logistics information system in the building of some common problems. According to logistics information systems planning methods and principles set out logistics information system to optimize the management model.

关键词： modern logistics information network e-commerce

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Synergistic Catalysis of Binary RuP Nanoclusters on Nitrogen-Functionalized Hollow Mesoporous Carbon in Hydrogen Production from the Hydrolysis of Ammonia Borane

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JOURNAL OF PHYSICAL CHEMISTRY LETTERS 2021年第1期12卷 696-703页

作者： Lv, Hao Wei, Ren guo, xuwen Sun, Lizhi Liu, Ben Sichuan Univ Coll Chem Chengdu 610064 Peoples R China Nanjing Normal Univ Jiangsu Collaborat Innovat Ctr Biomed Funct Mat Sch Chem & Mat Sci Jiangsu Key Lab New Power Batteries Nanjing 210023 Peoples R China

Exploring highly efficient nanocatalysts for hydrogen (H-2) production from catalytic hydrolysis of ammonia borane (AB) under ambient conditions and further unveiling their catalytic mechanism are of critical importance for renewable energy conversion technologies but remain big challenges. Herein, ultrafine binary RuP alloy nanoclusters homogeneously encapsulated onto nitrogen-functionalized hollow mesoporous carbon supports (RuP@NHMCs) are reported as a high-performance platinum (Pt)-free nanocatalyst for catalytic hydrolysis of AB at room temperature. Remarkable catalytic activity with a very high turnover frequency of 1774 mol(H2) mol(Ru)(-1) min(-1) and a low activation energy of 36.3 kJ mol(-1) is observed based on compositional and structural synergies of RuP@NHMCs. Results of control experiments and catalytic kinetics studies reveal that the rate-determining step of catalytic hydrolysis of AB is the oxidation cleavage of a covalently stable H-OH bond, while RuP@NHMCs result in multiple electronic, functional, size, and support effects that kinetically accelerate the cleavage of attacked H-OH. Furthermore, RuP@NHMCs exhibit a good catalytic activity with a high yield of >99% for tandem hydrogenation of nitroarenes coupled with the hydrolysis of AB. We strongly believe that the catalyst design principle reported here could provide a new opportunity for synthesizing other Pt-free high-performance nanocatalysts.

关键词： Catalysts Catalytic activity Nanoclusters Hydrolysis Nanocatalysts

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Inhibition of gene expression of trehalase enhances drought resistance in transgenic tobacco

Inhibition of gene expression of trehalase enhances drought ...

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4th International Conference on Bioinformatics and Biomedical Engineering (iCBBE)

作者： guo Bei Song Yanzhai guo xuwen Wang Wenping Ding Ning Beijing Agr Univ Dept Biotechnol Beijing Peoples R China

ISBN: (纸本)9781424447138

The representative individuals, CK (non-transgenic), 121 (with pBI121 vector), 1285 (with pGSA1285 vector), T4 (with gene of trehalase, TRE), S1 (with gene of trehalose -6 -phosphate synthase, TPS), P3 (with gene of trehalose -6 -phosphate phosphatase, TPP), a3 (with anti-TRE gene), i2 (with RNAi-TRE gene), were selected for identification of drought resistance, and the Malondialdehyde (MDA), relative conductivity have been measured after water-stress during this experiment. The results showed that the transgenic tobaccos with anti-TRE and RNAiTRE grew better than other individuals under water-stress conditions;conductivity of i2 was lower than other plants. Meantime, i2 has performance of some special features. These indicate that through application the antisense RNA and RNA interference technology to trehalase gene, it is possible to make the receptor trehalose metabolism changes. The inhibition of gene expression of trehalase can led to the accumulation of trehalose content and the enhancement of drought resistance in the transgenic tobaccos.

关键词： trehalase geng expression transgenic tobacco drought resistance

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Ultrathin and Wavy PdB Alloy Nanowires with Controlled Surface Defects for Enhanced Ethanol Oxidation Electrocatalysis

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ACS APPLIED MATERIALS & INTERFACES 2021年第15期13卷 17599-17607页

作者： Wang, Yaru Lv, Hao Sun, Lizhi guo, xuwen Xu, Dongdong Liu, Ben Nanjing Normal Univ Jiangsu Collaborat Innovat Ctr Biomed Funct Mat Sch Chem & Mat Sci Jiangsu Key Lab New Power Batteries Nanjing 210023 Peoples R China Sichuan Univ Coll Chem Chengdu 610064 Peoples R China

Engineering crystalline structures/defects and elemental compositions is synthetically critical to optimize surface features of noble metal nanocrystals and thus improve their catalytic performances in various reactions. In this manuscript, we report a facile one-step aqueous synthesis of one-dimensional (1D) noble metal-metalloid alloy nanowires (NWs) with an ultrathin and wavy morphology, controlled crystalline defects, and binary PdB compositions as a highly efficient catalyst toward the electrochemical ethanol oxidation reaction (EOR). We show that the utilization of hexadecylpyridinium chloride as functional surfactant is of great importance to confine in-the-columnar epitaxial nucleation of anisotropic ultrathin PdB NWs, while the attachment growth precisely controls their surface crystalline defects with a wavy morphology. Meanwhile, this strategy is synthetically universal and can be readily extended to engineer an ultrathin wavy morphology and crystalline defect of ternary PdMB (M = Cu and Pt) alloy NWs. Owing to multiple structural and compositional merits, resultant PdB alloy NWs synergistically expose more electrocatalytically active sites and also kinetically accelerate the removal of CO-related poisons, remarkably improving electrocatalytic EOR activity and stability compared to their counterpart catalysts. Besides, wavy PdB alloy NWs are also electrochemically more active for electrocatalytic oxidation of other alcohols (methanol, glycerol, and glucose). The findings reported here thus shed a bright light on rational design of the high-performance metal alloy catalysts for their potential applications in fine chemical synthesis, fuel cells, and beyond.

关键词： nanowires crystalline defects metal-metalloid catalysis ethanol oxidation reaction

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Highly efficient synthesis of hydrogen-bonded aromatic tetramers as macrocyclic receptors for selective recognition of lithium ions

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ORGANIC CHEMISTRY FRONTIERS 2019年第15期6卷 2654-2661页

作者： guo, xuwen Yang, Yizhou Peng, Zhiyong Cai, Yimin Feng, Wen Yuan, Lihua Sichuan Univ Coll Chem Key Lab Radiat Phys & Technol Minist Educ Chengdu 610064 Sichuan Peoples R China

Persistently folded aromatic amide macrocycles comprising four monomeric units (biphenyl-cyclo[4]aramide) were synthesized with high efficiency via a one-step approach along with the larger cyclic oligomer, biphenyl-cyclo[8]aramide as a minor product. Such cyclic hydrogen-bonded aromatic tetramers feature four amide oxygens enclosing a cavity with small dimensions, enabling the selective complexation of alkali metal ions, particularly Li+, with high affinity. The cyclization efficiency and selectivity of smaller macrocycles was further improved using fragment coupling and Li+-based template approaches. In addition, the superior binding ability of biphenyl-cyclo[4]aramide towards Li+ over its acyclic analogues was observed, demonstrating a remarkable macrocyclic effect.

关键词： Amides

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Empirical analysis on the relationship between the entry of foreign banks and risk-taking behavior of Chinese commercial Banks

Empirical analysis on the relationship between the entry of ...

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International Conference on Business Management and Electronic Information

作者： Li, Min guo, xuwen Zhang, Lijing Sen, Yanyan Economic and Management Department Henan Institute of Science and Technology Xinxiang China Foreign Language Department Henan Institute of Science and Technology Xinxiang China

ISBN: (纸本)9781612841069

This thesis chooses the Z-score index to measure commercial banks' risk-taking behavior. Then Panel data model is used to empirically analyze in the year from 2001 to 2008, it is indicated that by using non-linear model, there is a U-shape non-linear relation between foreign banks' entry degree and the risk-taking behavior of Chinese banks, and the effect is embodied by the foreign bank's portion in China's capital. © 2011 IEEE.

关键词： Risk assessment

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Study of university physics teaching based on information technology with education practice

Study of university physics teaching based on information te...

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作者： Cao, Yonghua Gao, Yinhao guo, xuwen Zhang, Lianfeng Mechanical and Electrical Department Henan Institute of Science Technology University Xinxiang Henan China Economics and Management Department Henan Institute of Science Technology University Xinxiang Henan China

ISBN: (纸本)9783642237522

Today's university physics teaching is facing some difficulties such as short teaching hours and richer contents. This article firstly analyses the present situation of university physics. Then it points out that the way out of the university physics teaching reform is the organic integration of information technology and university physics teaching. The additional role of information technology would be gave full play and then the teaching methods can be optimized. According to teaching practice, some suggestions about integrated approach are proposed in this article. © 2011 Springer-Verlag Berlin Heidelberg.

关键词： Computers

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