检索结果-南通市图书馆

Effect of preparation methods on the structure and catalytic performance of Fe–Zn/K catalysts for co2 hydrogenation to light olefins

引用

Chinese Journal of Chemical Engineering 2018年第4期26卷 761-767页

作者： Xu Wang Jianli zhang Jingyu Chen Qingxiang Ma Subing Fan Tiansheng Zhao State Key Laboratory of High-effidency Utilization of coal and Green Chemical Engineering College of Chemistry & Chemical Engineering Ningxia University Yinchuan 750021 China

Potassium promoted iron–zinc catalysts prepared by co-precipitation method(C–Fe–Zn/K),solvothermal method(S–Fe–Zn/K)and hydrothermal method(H–Fe–Zn/K)could selectively convert co_2to light olefins,*** physicochemical properties of the obtained catalysts were determined by SEM,N_2physisorption,XRD,H_2-TPR,co_2-TPD and XPS *** results demonstrated that preparation methods had great influences on the morphology,phase structures,reduction and adsorption behavior,and hence the catalytic performance of the *** samples prepared by hydrothermal and co-precipitation method generated small uniform particles and led to lower specific surface *** contrast,microspheres with larger specific surface area were formed by self-assembly of nanosheets using solvothermal ***_2O_4was the only detectable phase in the fresh C–2Fe–1Zn/K,S–3Fe–1Zn/K and S–2Fe–1Zn/K ***_2O_4and ZnO co-existed with increasing Zncontent in S–1Fe–1Zn/K sample,while ZnO and Fe_2O_3could be observed over H–2Fe–1Zn/K *** the used samples contained Fe_3O_4,ZnO and Fe_5C_*** peak intensity of ZnO was strong in the AR-H–2Fe–1Zn/K sample while it was the lowest in the AR-C–2Fe–1Zn/K sample after *** formation of ZnFe_2O_4increased the interaction between iron and zinc for C–2Fe–1Zn/K and S–Fe–Zn/K samples,causing easier reduction of Fe_2O_3to Fe_3O_*** surface basicity of the sample prepared by co-precipitation method was much more than that of the other two *** co_2hydrogenation,all the catalysts showed good activity and olefin *** co selectivity was increased with increasing Zncontent over S–Fe–Zn/K samples.H–2Fe–1Zn/K catalyst preferred to the production of C_5^+***_2conversion of 54.76%and C_2~=–C_4~=contents of 57.38%were obtained on C–2Fe–1Zn/K sample,respectively.

关键词： co2 hydrogenation Light olefins Preparation methods Iron–zinc catalyst

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Investigation on wavelength switching of widely tunable SGDBR lasers

引用

Chinese Science Bulletin 2009年第20期54卷 3709-3715页

作者： JIANG Shan DONG Lei zhang RuiKang XIE ShiZhong Accelink Technologies co. Ltd. Wuhan 430074 China School of Information Science and Engineering Shandong University Jinan 250100 China Department of Electronic Engineering Tsinghua University Beijing 100084 China

The sampled-grating distributed Bragg reflector(SGDBR) laser is a typical and important photonic integrated device,and has potential wide application to agile optical networks.A new dynamic model for this device has been developed,which combines the traveling-wave method for the active region and the transfer-matrix method for the passive sections into a single *** behaviors of wave-length switching of the SGDBR laser,which include the transient spectrum and mode competition,have been studied in detail using this model.A new efficient way has been proposed to improve the wavelength switching performance only by increasing the coupling coefficients without changing the carrier density.

关键词：可调谐激光器分布布拉格反射镜光子集成器件动态模型波长交换取样光栅开关性能耦合系数

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

comparison of corrosion mechanisms of 510L low alloy steel treated by ACS and EPS techniques under various service environments

引用

Journal of Iron and Steel Research International 2024年第2期31卷 501-518页

作者： Bao-sheng Liu Peng-fei Xu Shao-hua zhang Yan-rui Li Li-ming Mou Jia-li Li Yue-zhong zhang Pei-mao Fu Fa-cai Shi college of Materials Science and Engineering Taiyuan University of Science and TechnologyTaiyuan030024ShanxiChina college of Chemical and Biological Engineering Taiyuan University of Science and TechnologyTaiyuan030024ShanxiChina Technical Center Taiyuan Iron and Steel(Group)Co.Ltd.Taiyuan030003ShanxiChina

The corrosion mechanism of 510L low alloy steel treated by acid-cleaned surface(ACS)and eco-pickled surface(EPS)techniques in three simulated solutions(S0:atmospheric environment;S1:soil environment;S2:industrial environment)and the influence of interaction between different corrosive anions on corrosion were *** results show that the total corrosion rates of samples in three simulated solutions were in order of S2>S0>S1,which is simultaneously correlated with initial corrosion dissolution processes as well as after the formation of corrosion ***3−will inhibit the initial corrosion owing to the formation of films,whereas HSO3−will accelerate the dissolutions of the matrix based on the synergistic action of HSO3−and Cl−.On the other hand,there is no significant difference in corrosion rates between the samples treated by ACS and EPS *** EPS technique that is safe,reusable and environmentally friendly can be further widely used in future work.

关键词： corrosion mechanism Low alloy steel Simulated solution Surface technique Immersion time

来源：

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

Multi-Equipment Detection Method for Distribution Lines Based on Improved YOLOx-s

引用

computers, Materials & continua 2023年第12期77卷 2735-2749页

作者： Lei Hu Yuanwen Lu Si Wang Wenbin Wang Yongmei zhang School of computer and Information Engineering Jiangxi Normal UniversityNanchang330022China School of Digital Industry Jiangxi Normal UniversityShangrao334005China Department of Science and Technology State Grid Jiangxi Electric Power Research InstituteNanchang330096China School of Information North China University of TechnologyBeijing100144China

The YOLOx-s network does not sufficiently meet the accuracy demand of equipment detection in the autonomous inspection of distribution lines by Unmanned Aerial Vehicle(UAV)due to the complex background of distribution lines,variable morphology of equipment,and large differences in equipment ***,aiming at the difficult detection of power equipment in UAV inspection images,we propose a multi-equipment detection method for inspection of distribution lines based on the *** on the YOLOx-s network,we make the following improvements:1)The Receptive Field Block(RFB)module is added after the shallow feature layer of the backbone network to expand the receptive field of the network.2)The coordinate Attention(CA)module is added to obtain the spatial direction information of the targets and improve the accuracy of target localization.3)After the first fusion of features in the Path Aggregation Network(PANet),the Adaptively Spatial Feature Fusion(ASFF)module is added to achieve efficient re-fusion of multi-scale deep and shallow feature maps by assigning adaptive weight parameters to features at different scales.4)The loss function Binary Cross Entropy(BCE)Loss in YOLOx-s is replaced by Focal Loss to alleviate the difficulty of network convergence caused by the imbalance between positive and negative samples of small-sized *** experiments take a private dataset consisting of four types of power equipment:Transformers,Isolators,Drop Fuses,and Lightning *** average,the mean Average Precision(mAP)of the proposed method can reach 93.64%,an increase of 3.27%.The experimental results show that the proposed method can better identify multiple types of power equipment of different scales at the same time,which helps to improve the intelligence of UAV autonomous inspection in distribution lines.

关键词： Distribution lines UAV autonomous inspection power equipment detection YOLOx-s

来源：

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

Self-reduction of Manganese-rich Slag Briquette containing Carbon

引用

Journal of Iron and Steel Research International 2015年第5期22卷 402-407页

作者： Bo zhang Zheng-liang XUE Ting-ting ZHU Jiang DONG The State Key Laboratory of Refractories and Metallurgy Wuhan University of Science and Technology

The self-reduction experiment of manganese-rich slag briquette containing carbon was carried out in a high- temperature carbon tube furnace. The main factors affecting the reduction rate were analyzed, and the kinetic model of reduction was established. The results show that the increase of basicity of briquette has an obvious effect on im- proving reduction rate. When the carbon ratio of briquettes is 1.2 and its basicity is 1.0, the reduction rate can reach 90 %. It can accelerate reduction process and decrease reduction time when the appropriate flux CaF2 is added to the briquette. The apparent activation energy of chemical reaction is 24.07 kJ/mol, and the apparent activation energy of internal diffusion is 107.55 kJ/mol by calculation. Therefore, the reduction rate of briquette is determined by the mass transfer of co in the product layer.

关键词： manganese-rich slag briquette containing carbons self-reduction kinetics tephroite

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Hawk‐eye‐inspired perception algorithm of stereo vision for obtaining orchard 3D point cloud navigation map

引用

CAAI Transactions on Intelligence Technology 2023年第3期8卷 987-1001页

作者： Zichao zhang Jian Chen Xinyu Xu Cunjia Liu Yu Han college of Engineering China Agricultural UniversityBeijingChina Jiangsu Province and Education Ministry co‐sponsored Synergistic Innovation Center of Modern Agricultural Equipment Jiangsu UniversityZhenjiangChina Key Laboratory of Spatial‐temporal Big Data Analysis and Application of Natural Resources in Megacities MNRShanghaiChina Department of Aeronautical and Automotive Engineering Loughborough UniversityLoughboroughLeicestershireUK college of Water Resources and Civil Engineering China Agricultural UniversityBeijingChina State Key Laboratory of Virtual Reality Technology and Systems Beihang UniversityBeijingChina Key Laboratory of Urban Land Resources Monitoring and Simulation Ministry of Natural ResourcesShenzhenChina

The binocular stereo vision is the lowest cost sensor for obtaining 3D *** the weakness of long‐distance measurement and stability,the improvement of accuracy and stability of stereo vision is urgently required for application of precision *** address the challenges of stereo vision long‐distance measurement and stable perception without hardware upgrade,inspired by hawk eyes,higher resolution perception and the adaptive HDR(High Dynamic Range)were introduced in this *** the function from physiological structure of‘deep fovea’and‘shallow fovea’of hawk eye,the higher resolution reconstruction method in this paper was aimed at ac-curacy *** by adjustment of pupils,the adaptive HDR method was proposed for high dynamic range optimisation and stable *** various light conditions,compared with default stereo vision,the accuracy of proposed algorithm was improved by 28.0%evaluated by error ratio,and the stability was improved by 26.56%by disparity *** fixed distance measurement,the maximum improvement was 78.6%by standard *** on the hawk‐eye‐inspired perception algorithm,the point cloud of orchard was improved both in quality and *** hawk‐eye‐inspired perception algorithm contributed great advance in binocular 3D point cloud recon-struction in orchard navigation map.

关键词： adaptive high dynamic range binocular stereo vision hawk‐eye‐inspired perception point cloud of orchard super‐resolution generative adversarial network

来源：

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

Behavioral Decision-Making of Key Stakeholders in Public-Private Partnerships:A Hybrid Method and Benefit Distribution Study

引用

computer Modeling in Engineering & Sciences 2023年第9期136卷 2895-2934页

作者： Guoshuai Sun Wanyi zhang Jiuying Dong Shuping Wan Jiao Feng School of Economics and Management Liaoning University of TechnologyJinzhou121001China School of Information Management Jiangxi University of Finance and EconomicsNanchang330032China Post-Doctoral Research Center Zhongda Construction Co.Ltd.Guangzhou510280China School of Science Shanghai Institute of TechnologyShanghai201418China School of Maritime Economics and Management Dalian Maritime UniversityDalian116026China

Public-private partnerships(PPPs)have been used by governments around the world to procure and construct infrastructural *** relies on private sector expertise and funding to achieve this lofty ***,given the uncertainties of project management,transparency,accountability,and expropriation,this phenomenon has gained tremendous attention in recent years due to the important role it plays in curbing infrastructural deficits ***,the reasonable benefit distribution scheme in a PPP project is related to the behavior decisionmaking of the government and social capital,aswell as the performance of the *** this paper,the government and social capital which are the key stakeholders of PPP projects were selected as the research *** on the fuzzy expected value model and game theory,a hybrid method was adopted in this research taking into account the different risk preferences of both public entities and private parties under the fuzzy demand *** alleviate the problem of insufficient utilization of social capital in a PPP project,this paper seeks to grasp the relationship that exists between the benefit distribution of stakeholders,their behavioral decision-making,and project performance,given that they impact the performance of both public entities and private parties,as well as assist in maximizing the overall utility of the ***,four game models were constructed in this study,while the expected value and opportunity-constrained programming model for optimal decision-making were derived using alternate perspectives of both centralized decision-making and decentralized ***,the optimal behavioral decision-making of public entities and private parties in four scenarios was discussed and thereafter compared,which led to an ensuing discussion on the benefit distribution system under centralized ***,based on an example case,the influence of different confiden

关键词： PPP fuzzy expected value game theory behavioral decision-making benefit distribution hybrid method

来源：

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

Algorithm for retrieving surface pressure from hyper-spectral measurements in oxygen A-band

引用

Chinese Science Bulletin 2014年第14期59卷 1492-1498页

作者： Hailei Liu Minzheng Duan Daren L Yan zhang Institute of Atmospheric Physics Chinese Academy of Sciences Chengdu University of Information Technology Beijing Institute of Remote Sensing Information Application

An algorithm for retrieving the surface pressure from oxygen A-band measurements in the future Chinese co2satellite(CarbonSpec/TanSat)was *** ful physical radiative transfer model,vector radiative transfe model based on successive order of scattering,which i based on the successive order of scattering approach,wa used to simulate the measurements of CarbonSpec/TanSat as well as the kernel matrix in the inversion algorithm,and then the surface pressure and other related atmospheric parameters such as aerosol optical depth(AOD),surface albedo,and temperature were derived through optima estimation *** of the algorithm to surface albedo,solar zenith angle(SZA),viewing zenith angle(VZA),aerosol type,and AOD were investigated,and the results showed that the absolute error of retrieved surface pressure increases with decreasing surface albedo o increasing SZA and *** accuracy of\4 hPa ove bright surfaces(surface albedo C0.15)could be derived fo various SZAs and viewing ***,the algorithm can simultaneously retrieve the surface albedo AOD,and its vertical distribution indicated by scale

关键词：表面压力求逆算法光谱测量波段氧气检索气溶胶光学厚度地表反照率

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Hurricane damage assessment for residential construction considering the non-stationarity in hurricane intensity and frequency

引用

Acta Oceanologica Sinica 2016年第12期35卷 110-118页

作者： WANG Cao LI Quanwang PANG Long ZOU Aming zhang Long Department of Civil Engineering Tsinghua University CCCC Highway consultants co. Ltd.

Natural hazards such as hurricanes may cause extensive economic losses and social disruption for civil structures and infrastructures in coastal areas, implying the importance of understanding the construction performance subjected to hurricanes and assessing the hurricane damages properly. The intensity and frequency of hurricanes have been reported to change with time due to the potential impact of climate *** this paper, a probability-based model of hurricane damage assessment for coastal constructions is proposed taking into account the non-stationarity in hurricane intensity and frequency. The nonhomogeneous Poisson process is employed to model the non-stationarity in hurricane occurrence while the non-stationarity in hurricane intensity is reflected by the time-variant statistical parameters(e.g., mean value and/or standard deviation), with which the mean value and variation of the cumulative hurricane damage are evaluated explicitly. The Miami-Dade county, Florida, USA, is chosen to illustrate the hurricane damage assessment method proposed in this paper. The role of non-stationarity in hurricane intensity and occurrence rate due to climate change in hurricane damage is investigated using some representative changing patterns of hurricane parameters.

关键词： hurricane damage assessment intensity frequency non-stationarity climate change

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Supported bimetallic catalyst Pt-Pb/SiO2 for selective conversion of nitrobenzene to p-aminophenol in pressurized co2/H2O system

引用

Chinese Chemical Letters 2017年第2期28卷 307-311页

作者： Ting-Ting zhang Jing-Yang Jiang Yan-Hua Wang State Key Laboratory of Fine Chemicals Faculty of Chemical Environmental and Biological Sdence and Technology Dalian University of Technology Dalian 116024 China

Various supported Pt-Pb bimetallic catalysts were prepared and applied for the catalytic conversion of nitrobenzene to p-aminophenol in the environmentally benign pressurized co2/H2O *** the bimetallic catalysts prepared,Pt-Pb/SiO2 is the best and nitrobenzene could be converted to paminophenol with a selectivity as high as 82% when the reaction was carried out using this catalyst at110 ℃ under 5 MPa co2 and 0.2 MPa H2.

关键词： Nitrobenzene p-Aminophenol Pt-Pb bimetallic catalysts co2/H2O system Environmentally benign

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

欢迎您,

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

请选择保存的检索档案：

请选择收藏分类：

通借通还

欢迎您,

建议与咨询 留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

请选择保存的检索档案： 新增检索档案 确定 取消

请选择收藏分类： 新增自定义分类 确定 取消

通借通还

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

请选择保存的检索档案：

请选择收藏分类：