检索结果-南通市图书馆

Metal-Free C_(3)N_(4) with plentiful nitrogen vacancy and increased specific surface area for electrocatalytic nitrogen reduction

在线全文

学校读者我要写书评

暂无评论

Journal of Energy Chemistry 2021年第9期30卷 546-555页

作者： Ziming Zhao Yu long Sha luo Yutong luo Ming Chen Jiantai Ma State Key Laboratory of Applied Organic Chemistry(SKLAOC) College of Chemistry and Chemical EngineeringLanzhou UniversityLanzhou 730000GansuChina

As a substitute for synthetic ammonia under mild condition, electrocatalytic nitrogen reduction reaction(NRR) provides a hopeful approach for the development of ammonia. Nevertheless, the current development of NRR electrocatalysts is far from enough and a systematic research is needed to gain a better improvement. This article presents that 2 D C_(3)N_(4)-NV with a large specific surface area and abundant nitrogen vacancies is prepared by a simple and feasible method, and used as a metal-free catalyst for electrocatalytic NRR. Experiment result and density functional theory(DFT) calculation reveal that nitrogen vacancies in 2 D C_(3)N_(4)-NV can act as an efficient active site for catalytic NRR, which is conducive to capturing and activating N_(2), lowering Gibbs free energy(DG) in reaction and inhibiting hydrogen evolution reaction(HER) at the same time. In addition, the larger specific surface area also makes more active site exposed, which is good for the contact between the electrolyte and the active site, thus enhancing its NRR activity. The electrocatalyst shows an excellent catalytic activity for NRR in 0.1 M HCl, including Faradaic efficiency of 10.96%, NH_(3) yields of 17.85 lg h^(-1) mg_(cat)^(-1)., and good stability(over 20 h).

关键词： 2D C_(3)N_(4)-NV Larger specific surface area Nitrogen vacancy Electrocatalyst NRR

Correlations in Werner States

在线全文

学校读者我要写书评

暂无评论

Communications in Theoretical Physics 2008年第2期49卷 327-328页

作者： luo Shun-long LI Nan Academy of Mathematics and Systems Science the Chinese Academy of Sciences Beijing 100080 China

Werner states are paradigmatic examples of quantum states and play an innovative role in quantum information theory. In investigating the correlating capability of Werner states, we find the curious phenomenon that quantum correlations, as quantified by the entanglement of formation, may exceed the total correlations, as measured by the quantum mutual information. Consequently, though the entanglement of formation is so widely used in quantifying entanglement, it cannot be interpreted as a consistent measure of quantum correlations per se if we accept the folklore that total correlations are measured （or rather upper bounded） by the quantum mutual information.

关键词： total correlations quantum correlations entanglement of formation Werner states

Normalized solutions for a fourth-order Schrődinger equation with a positive second-order dispersion coefficient

在线全文

学校读者我要写书评

暂无评论

Science China Mathematics 2023年第6期66卷 1237-1262页

作者： xiao luo Tao Yang School of Mathematics Hefei University of TechnologyHefei 230009China Department of Mathematics Zhejiang Normal UniversityJinhua 321004China

In this paper,we study normalized solutions to a fourth-order Schrődinger equation with a positive second-order dispersion coefficient in the mass supercritical *** the well-studied case where the second-order term is zero or negative,the geometrical structure of the corresponding energy functional changes dramatically and this makes the solution set *** suitable control of the second-order dispersion coefficient and mass,we find at least two radial normalized solutions,a ground state and an excited state,together with some asymptotic *** is worth pointing out that in the considered repulsive case,the compactness analysis of the related Palais-Smale sequences becomes more *** forces the implementation of refined estimates of the Lagrange multiplier and the energy level to obtain normalized solutions.

关键词： fourth-order Schrodinger equation mixed dispersion normalized solution variational method

Combined Laparoscopic Splenectomy and Esophagogastric Devascularization versus Open Splenectomy and Esophagogastric Devascularization for Portal Hypertension due to Liver Cirrhosis

在线全文

学校读者我要写书评

暂无评论

Current Medical Science 2020年第1期40卷 117-122页

作者： Hong-ping luo Zhan-guo ZHANG Xin long Fei-long LIU xiao-ping CHEN Lei ZHANG Wan-guang ZHANG Hepatic Surgery Center Tongji HospitalTongji Medical CollegeHuazhong University of Science and TechnologyWuhcm 430030China

This study was conducted to compare the feasibility,safety and effectiveness of the combined-laparoscopic splenectomy and esophagogastric devascularization(C-LSED)with open splenectomy and esophagogastric devascularization surgery(OSED)in patients with portal hypertension due to liver *** February 2014 to June 2018,68 patients with portal hypertension were diagnosed as having serious gastroesophageal varices and/or hypersplenism in our *** patients underwent C-LSED and 38 patients received *** and outcomes were compared *** patients of C-LSED group required an intraoperative conversion to open *** shorter operating time,less blood loss,lower transfusion rates,shorter postoperative hospital stay,lower rates of complications were found in C-LSED group than in C-LSED group(Plong-term effects to open surgery.

关键词： liver cirrhosis portal hypertension laparoscopy splenectomy esophagogastric devascularization

健全全面从严治党体系:基本概念、内在要素与实践路径

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

学习论坛 2025年第1期 25-32页

作者：罗星中国纪检监察学院党建教研部北京100877

全面从严治党体系是一个由诸多要素按照一定结构形成的复杂整体,是管党治党各领域各方面相互贯通、有机结合形成的体系。全面从严治党体系生成于中国共产党管党治党的具体实践中,具有理论基础深厚性、参与主体多元性、任务布局全面性、... 详细信息

全面从严治党体系是一个由诸多要素按照一定结构形成的复杂整体,是管党治党各领域各方面相互贯通、有机结合形成的体系。全面从严治党体系生成于中国共产党管党治党的具体实践中,具有理论基础深厚性、参与主体多元性、任务布局全面性、治理过程常态性、方法路径多样性的特点。新时代全面从严治党体系包含了组织体系、教育体系、监管体系、制度体系、责任体系五大部分。“五大体系”相互联系、有机贯通,明确了全面从严治党的基本内容、重点领域与内在逻辑。健全全面从严治党体系,要坚持和加强党的全面领导,持续深化党的建设制度改革,在铲除腐败滋生土壤和条件上下更大功夫,丰富全面从严治党体系的理念方法和工作机制,加强对全面从严治党体系的学理阐释。

关键词：全面从严治党体系监督责任党的领导

Visible Light Promoted β-C-H Alkylation of β-Ketocarbonyls via a β-Enaminyl Radical Intermediate

在线全文

学校读者我要写书评

暂无评论

Chinese Journal of Chemistry 2018年第4期36卷 311-320页

作者： Dehong Wang long Zhang Sanzhong luo Key Laboratory of Molecular Recognition and Function Institute of Chemistry Chinese Academy of Sciences Beijing 100190 China College of Chemistry and Chemical Engineering University of Chinese Academy of Sciences Beijing 100490 China Collaborative Innovation Center of Chemical Science and Engineering (Tianjin) Tianjin 300071 China

A 5πe carbonyl activation mode is reported on the basis of photo-induced single-electron-transfer （SET） oxidation of a secondary enamine. The resultant β-enaminyl radical intermediate was trapped by a wide range o... 详细信息

关键词： secondary enamine β-enaminyl radical C-H alkylation photoredox catalysis β-ketocarbonyls

Development of a Compact Photoacoustic Tomography Imaging System with Dual Single-Element Transducers for Image Enhancement

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

Current Medical Science 2021年第6期41卷 1151-1157页

作者： Yong-jian ZHAO xiao-long ZHU Pei-yu luo Ang LI Wei xiao xiao xiao Li LIU Max Q.-H.MENG Department of Electronic and Electrical Engineering the Southern University of Science and TechnologyShenzhen 518055China Department of Electronic Engineering The Chinese University of Hong KongHong Kong 999077China Shenzhen Research Institute of The Chinese University of Hong Kong in Shenzhen Shenzhen 518172China

Objective:This paper proposes a new photoacoustic computed tomography(PACT)imaging system employing dual ultrasonic transducers with different *** imaging complex biological tissues,photoacoustic(PA)signals with multiple frequencies are produced simultaneously;however,due to the limited bandwidth of a single-frequency transducer,the received PA signals with specific frequencies may be missing,leading to a low imaging ***:In contrast to our previous work,the proposed system has a compact volume as well as specific selection of the detection center frequency of the transducer,which can provide a comprehensive range for the detection of PA *** this study,a series of numerical simulation and phantom experiments were performed to validate the efficacy of the developed PACT ***:The images generated by our system combined the advantages of both high resolution and ideal brightness/***:The interchangeability of transducers with different frequencies provides potential for clinical deployment under the circumstance where a single frequency transducer cannot perform well.

关键词： photoacoustic tomography dual transducers image enhancement signal responding range

大数据平台在市域治安风险防控中的设计与应用

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

河南师范大学学报（自然科学版） 2025年第1期53卷 100-105,I0006页

作者：罗宁中国人民公安大学侦查学院北京100038 河南警察学院侦查系郑州450046

通过对大数据技术在市域治安风险防控应用中的现状与不足进行剖析,深度挖掘市域治安风险源头和应对方法.探讨了适用于市域治安风险防范的大数据平台设计的要素基础与设计基础,对市域治安风险防控大数据平台进行结构设计、流程设计和功... 详细信息

通过对大数据技术在市域治安风险防控应用中的现状与不足进行剖析,深度挖掘市域治安风险源头和应对方法.探讨了适用于市域治安风险防范的大数据平台设计的要素基础与设计基础,对市域治安风险防控大数据平台进行结构设计、流程设计和功能设计,给出了矛盾纠纷风险防控、平安校园风险防控、重点关注人员时空轨迹分析等功能的实现方法,深度分析了由矛盾纠纷引起刑事案的内在因素(变量)及各因素的特征.为大数据在市域治安风险防控中的应用提供支撑.

关键词：大数据治安风险防控平台设计

On the Shadowing Property and Shadowable Point of Set-valued Dynamical Systems

在线全文

学校读者我要写书评

暂无评论

Acta Mathematica Sinica,English Series 2020年第12期36卷 1384-1394页

作者： xiao Fang luo xiao xiao NIE Jian Dong YIN Department of Mathematics Nanchang UniversityNanchang 330031P.R.China

In this article,the authors introduce the concept of shadowable points for set-valued dynamical systems,the pointwise version of the shadowing property,and prove that a set-valued dynamical system has the shadowing property iff every point in the phase space is shadowable;every chain transitive set-valued dynamical system has either the shadowing property or no shadowable points;and for a set-valued dynamical system there exists a shadowable point iff there exists a minimal shadowable *** the end,it is proved that a set-valued dynamical system with the shadowing property is totally transitive iff it is mixing and iff it has the specification property.

关键词： Shadowing property shadowable point set-valued dynamical system specification