检索结果-南通市图书馆

One-step conversion of methane and formaldehyde to ethanol over SA-FLP dual-active-site catalysts: A DFT study

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

Chinese Chemical Letters 2024年第4期35卷 544-548页

作者： Tao Ban xi-Yang Yu Hai-Kuo Tian Zheng-Qing Huang Chun-Ran Chang Shaanxi Key Laboratory of Energy Chemical Process Intensification School of Chemical Engineering and TechnologyXi'an Jiaotong UniversityXi'an 710049China Shaanxi Key Laboratory of Low Metamorphic Coal Clean Utilization School of Chemistry and Chemical EngineeringYulin UniversityYulin 719000China

One-step conversion of methane and formaldehyde into ethanol is a 100% atom-efficient process for carbon resources utilization and environment protection but still faces eminent challenges due to the lacking of efficient catalysts. Therefore, developing active and stable catalysts is crucial for the co-conversion of methane and formaldehyde. Herein, twelve kinds of “Single-Atom”-“Frustrated Lewis Pair”(SA-FLP)dual-active-site catalysts are designed for the direct conversion of methane and formaldehyde to ethanol based on density functional theory(DFT) calculations and microkinetic simulations. The results show that the SA-FLP dual active sites can simultaneously activate methane at the SA site and activate formaldehyde at the FLP site. Among the twelve designed SA-FLP catalysts, Fe1-FLP shows the best performance in the co-conversion of methane and formaldehyde to ethanol with the rate-determining barrier of 1.15 e *** is proved as the main product with the turnover frequency of 1.3.0}× 10^(-4)s^(-1)at 573.K and 3.*** work provides a universal strategy to design dual active sites on metal oxide materials and offers new insights into the effective conversion of methane and formaldehyde to desired C_(2. chemicals.

关键词： Single-atom Frustrated Lewis pairs Methane conversion Dual active sites Ethanol synthesis

维普期刊数据库

Binary particle swarm optimization with multiple evolutionary strategies

在线全文

学校读者我要写书评

暂无评论

science china(Information sciences) 2012年第11期55卷 2485-2494页

作者： ZHAO Jing1,HAN ChongZhao1 & WEI Bin2.1Ministry of Education Key Lab For Intelligent Networks and Network Security,State Key Laboratory for Manufacturing Systems Engineering,Institute of Integrated Automation,school of Electronics and Information Engineering,xi'an jiaotong {2.,xi'an 710049,china 2.nstitute of System Engineering,school of Electronics and Information Engineering,xi'an jiaotong {2.,xi'an 710049,china Ministry of Education Key Lab For Intelligent Networks and Network Security State Key Laboratory for Manufacturing Systems Engineering Institute of Integrated Automation School of Electronics and Information Engineering Xi’an Jiaotong University Xi’an China Institute of System Engineering School of Electronics and Information Engineering Xi’an Jiaotong University Xi’an China

This paper introduces a novel variation of binary particle swarm optimization(BPSO) algorithm and a further extension to improve its ***,mimicking the behaviors of some creatures group,multiple evolutionary strategies BPSO(MBPSO) is introduced which takes different evolutionary strategies for various particles according to their ***,on the basis of MBPSO,a new strategy is discussed to improve the performance of the MBPSO(M2.PSO) which adopts the concept of the mutation operator aiming to overcome the premature convergence and slow convergent speed during the later stages of the *** proposed two algorithms are tested on seven benchmark functions and their results are compared with those obtained by other *** results show that our methods outperform the other algorithms.

关键词： binary particle swarm optimizer evolutionary strategies swarm intelligence

Oxidation behavior of FeV_(2.O_(4)and FeCr_(2.O_(4)particles in the air:Nonisothermal kinetic and reaction mechanism

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

International Journal of Minerals,Metallurgy and materials 2024年第8期31卷 1839-1848页

作者： Junyi xiang xi Lu Luwei Bai Hongru Rao Sheng Liu Qingyun Huang Shengqin Zhang Guishang Pei Xuewei Lü school of Metallurgy and materials Engineering Chongqing University of Science and TechnologyChongqing 401331China Department of materials science and Engineering Seoul National UniversitySeoul 08826Rep.of Korea College of materials science and Engineering Chongqing UniversityChongqing 400044China

High-temperature oxidation behavior of ferrovanadium(FeV_(2.O_(4))and ferrochrome(FeCr_(2.O_(4))spinels is crucial for the application of spinel as an energy material,as well as for the clean usage of high-chromium vanadium ***,the nonisothermal oxidation behavior of FeV_(2.O_(4)and FeCr_(2.O_(4)prepared by high-temperature solid-state reaction was examined by thermogravimetry and X-ray diffraction(XRD)at heating rates of 5,10,and 15 K/*** apparent activation energy was determined by the Kissinger-Akahira-Sunose(KAS)method,whereas the mechanism function was elucidated by the Malek ***,in-situ XRD was conducted to deduce the phase transformation of the oxidation mechanism for FeV_(2.O_(4)and FeCr_(2.O_(4).The results reveal a gradual increase in the overall apparent activation energies for FeV_(2.O_(4)and FeCr_(2.O_(4)during *** stages of the oxidation process are observed based on the oxidation conversion rate of each *** oxidation mechanisms of FeV_(2.O_(4)and FeCr_(2.O_(4)are complex and have distinct *** particular,the chemical reaction controls the entire oxidation process for FeV_(2.O_(4),whereas that for FeCr_(2.O_(4)transitions from a three-dimensional diffusion model to a chemical reaction *** to the in-situ XRD results,numerous intermediate products are observed during the oxidation process of both compounds,eventually resulting in the final products FeVO_(4)and V2._(5)for FeV_(2.O_(4)and Fe_(2.O_(3.and Cr_(2.O_(3.for FeCr_(2.O_(4),respectively.

关键词： FeV_(2.O_(4) FeCr_(2.O_(4) oxidation nonisothermal kinetics mechanism

维普期刊数据库

Modeling and stabilization for a class of nonlinear networked control systems: A T-S fuzzy approach

在线全文

学校读者我要写书评

暂无评论

Progress in Natural science:materials International 2008年第8期18卷 1031-1037页

作者： xinchun Jiaa,*, Dawei Zhanga, Lihong Zheng a, Nanning Zheng b a school of Mathematics science, Shanxi {2., Taiyuan 03.006,{3. b Institute of Artificial Intelligent and Robotics, xi’an jiaotong university, xi’an 710049,{3. school of Mathematics science Shanxi University Taiyuan 030006 China Institute of Artificial Intelligent and Robotics Xi’an Jiaotong University Xi’an 710049 China

The stabilization problem for a class of nonlinear networked control systems (NCSs) is investigated in this paper. A Takagi-Sugeno (T-S) fuzzy model is employed to represent the nonlinear controlled plant in the NCSs. Based on parallel distributed compensation (PDC) technique, a novel model of the nonlinear NCSs is established firstly in consideration of both network-induced delay and packet losses in transmission. Then a stability condition of the nonlinear NCSs is presented in terms of linear matrix inequalities (LMIs) by using the Lyapunov-Krasovskii functional method and the delay input approach. Furthermore, the control design of the nonlinear NCSs is developed by means of LMIs. Finally, a numerical example is given to demonstrate the effectiveness of the proposed method.

关键词： Nonlinear networked control systems Takagi–Sugeno (T-S) fuzzy systems Stabilization Packet losses Network-induced delay Linear matrix inequality (LMI)

Visualization of cristae and mtDNA interactions via STED nanoscopy using a low saturation power probe

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

Light(science & Applications) 2024年第9期13卷 1741-1756页

作者： Wei Ren xichuan Ge Meiqi Li Jing Sun Shiyi Li Shu Gao Chunyan Shan Baoxiang Gao Peng xi Department of Biomedical Engineering National Biomedical Imaging CenterCollege of Future TechnologyPeking UniversityBeijing 100871China Key Laboratory of Analytical science and Technology of Hebei Province College of Chemistry and Material ScienceHebei UniversityBaoding 071002China school of Life sciences Peking UniversityBeijing 100871China National Center for Protein sciences Peking UniversityBeijing 100871China

Mitochondria are crucial organelles closely associated with cellular metabolism and *** DNA(mtDNA)encodes a variety of transcripts and proteins essential for cellular ***,the interaction between the inner membrane(IM)and mtDNA remains elusive due to the limitations in spatiotemporal resolution offered by conventional microscopy and the absence of suitable in vivo probes specifically targeting the ***,we have developed a novel fluorescence probe called HBmito Crimson,characterized by exceptional photostability,fluorogenicity within lipid membranes,and low saturation *** successfully achieved over 500 frames of lowpower stimulated emission depletion microscopy(STED)imaging to visualize the IM dynamics,with a spatial resolution of 40 *** utilizing dual-color imaging of the IM and mtDNA,it has been uncovered that mtDNA tends to habitat at mitochondrial tips or branch points,exhibiting an overall spatially uniform ***,the dynamics of mitochondria are intricately associated with the positioning of mtDNA,and fusion consistently occurs in close proximity to mtDNA to minimize pressure during cristae *** healthy cells,>66%of the mitochondria are Class III(i.e.,mitochondria>5μm or with>12.cristae),while it dropped to<18%in *** dynamics,orchestrated by cristae remodeling,foster the even distribution of ***,in conditions of apoptosis and ferroptosis where the cristae structure is compromised,mtDNA distribution becomes *** findings,achieved with unprecedented spatiotemporal resolution,reveal the intricate interplay between cristae and mtDNA and provide insights into the driving forces behind mtDNA distribution.

关键词： metabolism saturation utilizing

A directional MAC protocol with long-range communication ability in ad hoc networks

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

science china(Information sciences) 2012年第4期55卷 765-777页

作者： REN PinYi,FENG Jia & WANG YiChen school of Electronics and Information Engineering,xi’an jiaotong {2.,xi’an {3.,china school of Electronics and Information Engineering Xi’an Jiaotong University Xi’an China

To address the problem that long-range communication capability in ad hoc networks using directional antenna is not generally utilized,a directional media access control (DMAC) protocol with long-range communication (LRC) capability in ad hoc networks is *** the LRC-DMAC,the intermediate node uses a long-range orientation (LRO) algorithm to help the transmitter obtain the directional information of the receiver which is two hops ***,the long-range link between such two hops nodes can be set *** to whether the received power information is available or not,we propose two types of LRO algorithm:without the received power information,a basic LRO obtains the approximate directional informa-tion of the long-range receiver by a geometric relationship;however,the LRO-PI can calculate the accurate directional information of the long-range receiver using the received *** analysis indicates that the LRO algorithm achieves high accuracy when the relevant parameters are properly *** results show that the establishment of long-range links can effectively improve the network throughput and reduce the end-to-end delay.

关键词： ad hoc networks directional antenna MAC

Asynchronous cooperative communication systems:A survey on signal designs

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

science china(Information sciences) 2011年第8期54卷 1547-1561页

作者： WANG HuiMing 1,2.& xiA xiangGen 3.1 school of Electronic and Information Engineering, xi’an jiaotong university,{2.,china 2.State Key Laboratory of Integrated Services Networks, xidian university,xi’an 710049, china 3.Department of Electrical and Computer Engineering,university of Delaware,Newark,DE 19716,USA school of Electronic and Information Engineering Xi’an Jiaotong University Xi’an China State Key Laboratory of Integrated Services Networks Xidian University Xi’an China Department of Electrical and Computer Engineering University of Delaware Newark USA

Cooperative communications is a promising technique for future high speed wireless *** systems may be formulated as virtual multi-input multi-output (MIMO) systems where spatial/cooperetive diversity is a key advantage. However,different from MIMO systems,one of the major chal- lenges for cooperative communications systems is that the cooperative transmissions in cooperative systems may be neither time nor frequency synchronized,since the transmissions are from multiple cooperative nodes at different *** existing signal designs for co-located MIMO systems may not be able to collect the cooperative diversity in cooperative communications *** paper gives an overview of recent research efforts on combating the time and frequency asynchronism of the cooperative communication *** focus on the signal designs (or space-time codings/modulations) to achieve full cooperative diversity,and summarize some of the resent distributed space-timing coding and space-frequency coding techniques to combat timing errors and frequency offsets,and in the meantime to achieve full cooperative diversity,in both one-way and two-way cooperative networks.

关键词： cooperative communications time and frequency offsets space-time coding space-frequency codes full cooperative diversity linear receiver

Study of Multistage Project Risk Identification-Assessment Process Based on Objective Orientation

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

厦门大学学报（自然科学版） 2002年第S1期41卷 242-243页

作者： YANG Cai-xia, XU Yu (school of Management, xi’an jiaotong university,{2.,{3.)

Risk management of projects is about the real time ev aluation and making of decisions proactively in order to maximize the probabilit y of achieving or surpassing the targets set for project objectives. Project objective generally includes three elements: time, cost, quality. Risk occurrin g in the projects will affect these three factors to some various degrees in the end. There are different emphases in each stage and integrated balanced goals b etween the three factors. A large complex engineering project generally consists of several stages each of which has variable objective combinations leading to variable important risks. In order to achieve strategic goals on the schedule under the restriction of lim ited resources, the paper gives the analysis of the so-called risk identificati on-assessment process on the basis of objective orientation. In this paper the set of involved mostly hazards is presented in terms of given objective weight v ector, and so is the model of risk ranking .By reducing the range of risk factor s step by step, risk manager could pay more attention to important ventures and effectively control of them. According to different objective combination at different stages, primary risk f actor sets at different stages are given. With the probability and their various effects to project objectives, evaluation of these sets is made aiming to r educing of the scope of risks and providing decision maker with a better decisio ns support. Successful projects are those, which focus on the relevant business objectives t hroughout the whole process and seek to information integration across project l ife cycle. This paper also introduces the idea of real time process of risk iden tification-assessment and presents a flow chart as a demonstration.

关键词： risk identification-assessment project objectiv e objective weight vector risk ranking

维普期刊数据库

High temperature polyimide nanocomposites containing twodimensional nanofillers for improved thermal stability and capacitive energy storage performance

在线全文

学校读者我要写书评

暂无评论

Nano Research 2024年第8期17卷 7746-7755页

作者： Ding Ai Yuting Han Zongliang xie xi Pang Yuan Chang He Li Chenglong Wu Yonghong Cheng Guanglei Wu State Key Laboratory of Electrical Insulation and Power Equipment School of Electrical EngineeringXi’an Jiaotong UniversityXi’an 710049China Institute of materials for Energy and Environment State Key Laboratory of Bio-Fibers and Eco-TextilesCollege of Materials Science and EngineeringQingdao UniversityQingdao 266071China

Future electronic devices toward high integration and miniaturization demand reliable operation of dielectric materials at high electric fields and elevated ***,the electrical deterioration caused by Joule heat generation remains a persistent challenge to ***,the solution-processed polyimide(PI)nanocomposites with unique two-dimensional(2.)alumina nanoplates are *** improvements in the breakdown strength,charge–discharge efficiency and discharged energy density at elevated temperatures have been demonstrated in the composites,owing to simultaneously suppressed conduction loss and increased thermal conductivity upon the incorporation of 2. Al_(2.O_(3. nanofillers possessing excellent dielectric insulation and thermophysical *** predominance of Al_(2.O_(3. nanoplates in enhancing thermal stability and high-temperature capacitive performance over nanoparticles and nanowires is validated experimentally and is further rationalized via finite element ***,the Al_(2.O_(3. nanoplates filled PI nanocomposite exhibits a hightemperature capability up to 2.0℃ and remarkable efficiency(e.g.≥95% at 2.0 MV/m)over a wide temperature range,which outperforms commercial dielectric polymers and rivals the state-of-the-art polyimide nanocomposites.

关键词： capacitors polymer nanocomposites high temperature energy storage thermal stability