检索结果-南通市图书馆

Influence of limestone fillers on combustion characteristics of asphalt mortar for pavements

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

Chinese Physics B 2014年第7期23卷 494-498页

作者：吴珂朱凯吴昊韩君王金昌黄志义梁培 College of Civil and Architecture Engineering Zhejiang University Department of Chemical and Biochemical Engineering Technical University of DenmarkS?ltofts PladsBuilding 229DK-2800 Kgs. LyngbyDenmark Jiangsu Bao Li Asphalt Co. ltd College of Optical and Electronic Technology China Jiliang University

Asphalt materials will be ignited and release significant toxic fumes within tunnel fires. Thus, combustion character- istics of asphalt materials used in road tunnel should be studied in order to limit such an adverse effect. In the present work we study the influence of limestone fillers on combustion characteristics of asphalt mortar by thermogravimetric and kinetic analysis. It is shown that the combustion of asphalt mortar is not just a linear superposition of asphalt and limestone. The limestone will increase the ignition point and the activation energy of the primary volatile release, and will catalyze the char formation from the primary volatile release. Kinetic analysis shows that the primary volatile release stage of asphalt mortar combustion can be explained by a three-dimensional diffusion model, the secondary volatile release and char combustion stage can be explained by a model under the assumption of random nucleation and nuclei growth, whereas the limestone decomposition stage appears to follow the one-dimensional phase boundary model.

关键词： asphalt mortar limestone combustion kinetic analysis

Operation of Off-grid Power Supply System Using IoT Monitoring Platform for Oil and Gas Pipeline Based on RESOC

在线全文

学校读者我要写书评

暂无评论

CSEE Journal of Power and Energy Systems 2020年第1期6卷 12-21页

作者： Chenxing Xu Jian Wu Hailin Feng Andreas Ibrom Qing Zeng Jianfeng Zhang Na Li Qiang Hu College of Information Engineering Zhejiang A&F UniversityHangzhou 311300China Department of Environmental Engineering Technical University of Denmark2800 Kgs.LyngbyDenmark Tsinghua Sichuan Energy Internet Research Institute Chengdu 610213China CRRC Wind Power(Shandong)Co. LtdRepresentative Office in DenmarkRoskilde 4000Denmark Zhejiang Zhentai Energy Technology Co.ltd. Lishui 323000China

An oil and gas pipeline monitoring platform uses internet of things(IoT)to ensure safe operation in remote and unattended areas,through automatic monitoring and systematic control on equipment such as the cut-off valves and cathodic protection *** continuity and stability of power supplies for various equipment of an oil and gas pipeline IoT monitoring platform is *** is no single universal off-grid power supply method that is optimal for an oil and gas pipeline IoT monitoring platform in all different ***,it is necessary to select a suitable one according to the specific geographical location and meteorological *** paper proposes an off-grid power supply system comprised of a reversible solid oxide fuel cell(RESOC),photovoltaic(PV)and *** operating costs and the reliability of system operations under constraint conditions are the key determining objectives.A“PV+battery+RESOC”system operational optimization model is *** on the model,three types of off-grid power supply schemes are proposed,and three geographical locations with different meteorological conditions are selected as practical application *** Matlab Cplex solver is used to solve the different power supply modes of the three *** finally,the power supply scheme with the best reliability and economy under different geographical environments and meteorological conditions is obtained.

关键词： IoT oil and gas pipeline off-grid power supply system operational optimization reversible solid oxide fuel cell

Magnetic properties and magnetization mechanism of anisotropic NdFeB/SmFeN hybrid bonded magnets prepared with different coercivity NdFeB powders

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

稀土学报:英文版 2023年第9期41卷 1353-1359,I0003页

作者： Qisong Luo Yang Luo Zilong Wang Haijun Peng Wenlong Yan Wenjian Yan Tianhao Li Shengjie Zhu Dunbo Yu National Engineering Research Center for Rare Earth GRINM Group Co.LtdBeijing 100088China GRIREM Advanced Materials Co. LtdBejing 100088China General Research Institute for Nonferrous Metals Beijing 100088China

Anisotropic NdFeB/SmFeN hybrid bonded magnets were prepared by warm compaction process under an orientation magnetic field of 22 kOe,mixing with anisotropic SmFeN powders in different addition and HDDR-NdFeB powders in different *** the addition of 20 wt% SmFeN,the density and remanence of hybrid magnets increase from 5.58 g/cm~3,8.4 kgs to 6.02 g/cm~3,9.0 kgs,*** as the addition amount of SmFeN powders varies from 20 wt% to 40 wt%,the maximum energy product changes less than 0.5 *** addition,the magnetization process and the interactions between two powders were *** is found that the magnetization process of anisotropic NdFeB powders shows distinction in different initial *** addition of SmFeN powders promotes the rotation of NdFeB powders together with applied field,which is beneficial to the degree of alignment of NdFeB *** of the micron-sized long range coupling effect,the coercivity of hybrid magnets decreases slowly with the increase of low coercivity ***,the magnetization process of hybrid magnets is different from pure magnets,it increases rapidly at low field and then slowly,next leads to rapidity again and achieves the saturation magnetization finally.

关键词： Anisotropic hybrid bonded magnet NdFeB/SmFeN Coupling effect Magnetization process Coercivity Rare earths

Reduction and carburization of iron oxides for Fischer–Tropsch synthesis

在线全文

学校读者我要写书评

暂无评论

Journal of Energy Chemistry 2020年第12期29卷 48-61页

作者： Monia Runge Nielsen Asger Barkholt Moss Anton Simon Bjrnlund Xi Liu Axel Knop-Gericke Alexander YuKlyushin Jan-Dierk Grunwaldt Thomas LSheppard Dmitry EDoronkin Anna Zimina Thomas Eric Lyck Smitshuysen Christian Danvad Damsgaard Jakob Birkedal Wagner Thomas Willum Hansen DTU Nanolab Technical University of DenmarkDK-2800Kgs.LyngbyDenmark Department of Physics Technical University of DenmarkDK-2800Kgs.LyngbyDenmark SynCat@Beijing Synfuels China Technology Co.LtdBeijing 101407China School of Chemistry and Chemical Engineering Shanghai Jiao Tong UniversityShanghai 200240China Department of Inorganic Chemistry Fritz Haber Institute of the Max Planck SocietyD-14195 BerlinGermany Research Group Heterogeneous Reactions.Max Planck Institute for Chemical Energy Conversion D-45470 MulheimGermany Research Group Catalysis for Energy Helmholtz-Zentrum Berlin for Materials and Energy(BESSYⅡ)D-12489 BerlinGermany Institute for Chemical Technology and Polymer Chemistry Karlsruhe Institute of TechnologyD-76131 KarlsruheGermany Institute of Catalysis Research and Technology Karlsruhe Institute of TechnologyD-76344 Eggenstein-LeopoldshafenGermany

The activation of iron oxide Fischer–Tropsch Synthesis(FTS) catalysts was investigated during pretreatment: reduction in hydrogen followed by carburization in either CO or syngas mixture, or simultaneously reduction and carburization in syngas. A combination of different complementary in situ techniques was used to gain insight into the behavior of Fe-based FTS catalysts during activation. In situ XRD was used to identify the crystalline structures present during both reduction in hydrogen and carburization. An increase in reduction rate was established when increasing the temperature. A complete reduction was demonstrated in the ETEM and a grain size dependency was proven, i.e. bigger grains need higher temperature in order to reduce. XPS and XAS both indicate the formation of a small amount of carbonaceous species at the surface of the bulk metallic iron during carburization.

关键词： In situ characterization Fischer–Tropsch Catalyst reduction and carburization Iron oxides

计及热电耦合效应的SiC MOSFET阈值电压精确监测方法

在线全文

学校读者我要写书评

暂无评论

太阳能学报 2023年第2期44卷 445-452页

作者：杜明星信金蕾姚婉荣欧阳紫威天津市复杂系统控制理论及应用重点实验室(天津理工大学) 天津300384 天津中科华盈科技有限公司天津300300 丹麦技术大学电气工程系灵比2800 Kgs

在研究SiC MOSFET的阈值电压、体二极管电压、漏-源极通态电阻温度依赖性的基础上,分析偏压温度不稳定性(BTI)引起的V_(TH)的漂移规律,并探究其对温敏电参数(TSEPs)的影响规律。另外,在充分考虑温度和BTI对V_(TH)共同作用的影响下,提出... 详细信息

在研究SiC MOSFET的阈值电压、体二极管电压、漏-源极通态电阻温度依赖性的基础上,分析偏压温度不稳定性(BTI)引起的V_(TH)的漂移规律,并探究其对温敏电参数(TSEPs)的影响规律。另外,在充分考虑温度和BTI对V_(TH)共同作用的影响下,提出在小电流注入时使用体效应下的体二极管电压监测SiC MOSFET阈值电压的方法。该方法可在不同的结温(T_(j))下监测阈值电压,为校正其他TSEPs测量结温的准确性提供帮助。理论和实验结果证明了该方法的可行性。

关键词：碳化硅功率MOSFET 状态监测温敏电参数偏压温度不稳定性

Influence of geometry on the thermal performance of water pit seasonal heat storages for solar district heating

在线全文

学校读者我要写书评

暂无评论

Building Simulation 2021年第3期14卷 579-599页

作者： Yakai Bai Ming Yang Jianhua Fan Xiaoxia Li Longfei Chen Guofeng Yuan Zhifeng Wang Key Laboratory of Solar Thermal Energy and Photovoltaic Systems Chinese Academy of SciencesBeijing 700190China Institute of Electrical Engineering Chinese Academy of SciencesBeijing 100190China University of Chinese Academy of Sciences Beijing 100049China Department of Civil Engineering Technical University of DenmarkBrovej 1182800 Kgs.LyngbyDenmark Joint Laboratory Institute of Electrical EngineeringChinese Academy of Sciences and Guangdong Five Star Solar Energy Co.Ltd.Beijing 100190China Lanzhou University of Technology Gansu 730050China

The aim of the study is to investigate the influence of geometry on the thermal capacity and stratifications of a water pit heat storage for solar district heating.A TRNSYS component model for a truncated cone water pit was developed based on the coordinate transformation method and validated by experimental results from the water pit heat storage in Huangdicheng in *** thermal performance of 26 water pits with different heights and side wall slopes was calculated for 10 consecutive *** takes four to six years for the water pit to reach steady-state *** operation data from the tenth year was selected to evaluate the thermal performance of each *** results show that because of the thermal insulation on top of the water pit,the height to diameter ratio of a water pit with minimum annual heat loss was always smaller than *** annual storage efficiency of a water pit increases with side wall slope due to the reduced side wall *** is an almost linear increase in the thermal stratification number of a water pit with *** an increase in the height,thermal stratification in water pits with a steeper slope increased more gradually than water pits with a lower *** findings in this paper are relevant for the design optimization of water pits as seasonal thermal energy storages.

关键词： water pit seasonal heat storage truncated cone storage capacity thermal stratification coordinate transformation

Characterization and stability measurement of deployed multicore fibers for quantum applications

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

Photonics Research 2021年第10期9卷 1992-1997页

作者： DAVIDE BACCO NICOLA BIAGI ILARIA VAGNILUCA TETSUYA HAYASHI ANTONIO MECOZZI CRISTIAN ANTONELLI LEIF KOXENLØWE ALESSANDRO ZAVATTA CoE SPOC DTU FotonikTechnical University of Denmark2800 Kgs.LyngbyDenmark Istituto Nazionale di Ottica(CNR-INO) Largo E.Fermi 650125 FlorenceItaly LENS and Department of Physics and Astronomy University of Florence50019 Sesto FiorentinoItaly Department of Physics“Ettore Pancini” University of Naples“Federico II”Via Cinthia 2180126 NaplesItaly Optical Communications Laboratory Sumitomo Electric IndustriesLtd.244-8588 YokohamaJapan Department of Physical and Chemical Sciences University of L’Aquila67100 L’AquilaItaly National Laboratory of Advanced Optical Fibers for Photonics(FIBERS) CNIT67100 L’AquilaItaly

Multicore fibers are expected to be a game-changer in the coming decades thanks to their intrinsic properties,allowing a larger transmission bandwidth and a lower footprint in optical *** addition,multicore fibers have recently been explored for quantum communication,attesting to their uniqueness in transporting high-dimensional quantum ***,investigations and experiments reported in literature have been carried out in research laboratories,typically making use of short fiber links in controlled ***,the possibility of using long-distance multicore fibers for quantum applications is still to be *** characterize here for the first time,to the best of our knowledge,in terms of phase stability,multiple strands of a four-core multicore fiber installed underground in the city of L’Aquila,with an overall fiber length up to about 25 *** this preliminary study,we investigate the possibility of using such an infrastructure to implement quantumenhanced schemes,such as high-dimensional quantum key distribution,quantum-based environmental sensors,and more,in general,quantum communication protocols.

关键词： quantum fibers stability

Magnetic properties and microstructures of terbium coated and grain boundary diffusion treated sintered Nd-Fe-B magnets by magnetron sputtering

在线全文

学校读者我要写书评

暂无评论

Journal of Rare Earths 2021年第2期39卷 167-173页

作者： Wei Zhu Yang Luo Zilong Wang Xinyuan Bai Haijun Peng Dunbo Yu National Engineering Research Center for Rare Earth Materials GRINM Group Co.Ltd.Beijing 100088China GRIREM Advanced Materials Co. Ltd.Beijing 100088China General Research Institute for Nonferrous Metals Beijing 100088China

Tb coating on the surface of commercial sintered Nd-Fe-B magnet was prepared by DC magnetron *** secondary heat treatment was used to regulate the microstructure for the enhancement of coercivity,namely diffusion treatment and annealing *** coercivity increases significantly from 18.3 to 28.0 kOe,the remanence decreases slightly from 14.1 to 14.0 kgs,and the comprehensive magnetic properties are higher than 75(Hcj+(BH)_(max)=76.7).SEM results indicate that,on the one hand,950℃is the optimal diffusion *** diffusion temperature results in insufficient diffusion of Tb *** diffusion temperature can lead to the main phase grain growth,the decrease of Nd-rich phase,and forming holes in the *** the other hand,500℃is the optimal annealing *** annealing temperature can result in the reduction of Nd-rich *** annealing temperature can generate the non-defined Nd-rich thin layer between grains.

关键词： Sintered Nd-Fe-B magnets Magnetron sputtering Tb coating Magnetic properties Rare earths

Effects of grain boundary diffusion of PrCu alloy on microstructure and coercivity of hot deformed(Nd,Ce)-Fe-B magnets

在线全文

学校读者我要写书评

暂无评论

Journal of Rare Earths 2021年第8期39卷 986-992页

作者： Haijun Peng Dunbo Yu Xinyuan Bai Xiao Lin Yongjun Mao Zilong Wang Yang Luo National Engineering Research Center for Rare Earth Materials CRINM Group Co.Ltd.Beijing 100088China GRIREM Advanced Materials Co. Ltd.Beijing 100088China General Research Institute for Non/errous Metals Beijing 100088China

The technology of using high abundance rare earth element Ce in permanent magnets has attracted many *** this work,the magnetic properties and microstructures of hot deformed(Nd_(1-x)Ce_(x))_(13.8)Fe_(76.1)Co_(4)Ga_(0.5)B_(5.6) magnets and a selective magnet treated with PrCu grain boundary diffusion process(GBDP) were investigated *** is found that Ce is beneficial to improving the plastic deformation ability of NdFeB *** strongest c-axis orientation is achieved in the HD magnets with Ce concentration of x=0.3,resulting in good comprehensive magnetic properties of B_(r)=13.00 kgs,H_(cj)=10.12 kOe,(BH)_(max)=38.42 *** on that,the GBDP was implemented on the magnets with the best orientation using Pr_(68)Cu_(32) ribbons and the magnetic properties of B_(r)=12.87 kgs,H_(cj)=15.65 kOe,(BH)_(max)=37.48 MGOe were *** results of composition distribution and Curie temperature test of the GBDPed magnets illustrate that Pr diffuses into the(Nd,Ce)_(2)(Fe,Co)_(14)B grains to substitute Ce,which not only improves the Curie temperature of the grains,but also enhances the magnetic performance of the *** GBDP,the thermal stability of magnets has also been improved.

关键词： Nd-Ce-Fe-B GBDP Hot deformation Magnetic properties Microstructure Rare earths