检索结果-南通市图书馆

Effect of nucleating agents on the electrical properties of cross-linked polyethylene under tensile stress

在线全文

学校读者我要写书评

暂无评论

High Voltage 2024年第2期9卷 429-439页

作者： Yunqi Xing Jiahao Liu Jingang Su Junwei Zha Guochang Li ze Guo Xiaozhen Zhao Mengjia Feng State Key Laboratory of Reliability and Intelligence of Electrical Equipment Hebei University of TechnologyTianjinChina Electric Power Research Institute of State Grid Hebei Electric Power Supply Co. Ltd.ShijiazhuangChina Beijing Advanced Innovation Center for Materials Genome Engineering School of Chemistry and Biological EngineeringUniversity of Science&Technology BeijingBeijingChina Institute of Advanced Electrical Materials Qingdao University of Science and TechnologyQingdaoChina

During the operation of high-voltage cables,external stress and residual stress can affect the aggregated structure of insulating materials and lead to significant deterioration in their electrical *** investigate the evolution characteristics of the electrical properties of cross-linked polyethylene(XLPE)under mechanical stress,this paper ex-plains the relationship between the aggregated structure of XLPE and its electrical properties and proposes a method for improving insulation performance under me-chanical *** results show that metallocene polyethylene used as a nucleating agent can promote crystallisation through heterogeneous nucleation and increase Young's modulus by non-uniform nucleation,increasing crystallinity and reducing interplanar spacing,resulting in more complete crystal forms and reduced damage to the aggregated structure during the tensile *** nucleating agent modification,the XLPE crystallisation becomes more uniform,and interfacial adhesion forces *** weakened interface damage process between the amorphous and crystalline regions under tensile stress effectively inhibits the process of molecular chain polarisation turning and reduces trap *** modified XLPE crystal structure shows a tendency towards densification and enhanced molecular chain interactions,which can reduce the damage to the aggregated structure under tensile stress,while the reduced free volume inside the material and the shortened average free path of carriers can weaken the damage of high-energy electrons to molecular chains,thereby inhibiting the process of electrical tree *** results show that nucleating agents have great potential for maintaining the stable operation of XLPE cables under mechanical stress.

关键词： stress electrical damage

Sensitivity impacts owing to the variations in the type of zero-range pairing forces on the fission properties using the density functional theory

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Nuclear Science and Techniques 2024年第3期35卷 198-207页

作者： Yang Su ze-Yu Li Li-Le Liu Guo-Xiang Dong Xiao-Bao Wang Yong-Jing Chen China Nuclear Data Center China Institute of Atomic EnergyBeijing 102413China School of Science Huzhou UniversityHuzhou 313000China

Using the Skyrme density functional theory,potential energy surfaces of^(240)Pu with constraints on the axial quadrupole and octupole deformations(q_(20)and q_(30))were *** volume-like and surface-like pairing forces,as well as a combination of these two forces,were used for the Hartree–Fock–Bogoliubov *** in the least-energy fission path,fission barrier,pairing energy,total kinetic energy,scission line,and mass distribution of the fission fragments based on the different forms of the pairing forces were analyzed and *** fission dynamics were studied based on the timedependent generator coordinate method plus the Gaussian overlap *** results demonstrated a sensitivity of the mass and charge distributions of the fission fragments on the form of the pairing *** on the investigation of the neutron-induced fission of^(239)Pu,among the volume,mixed,and surface pairing forces,the mixed pairing force presented a good reproduction of the experimental data.

关键词： Nuclear fission Density functional theory Pairing force Potential energy surfaces Fission fragment distribution

Nano-flower spherical SnS2 combined with a special lithium storage mechanism as a multifunctional separator for lithium-sulfur batteries contributes to ultra-high initial discharge specific capacity

在线全文

学校读者我要写书评

暂无评论

Science China(Technological Sciences) 2024年第2期67卷 509-519页

作者： LIU HuaZhong XIONG YaPing HUANG MouZhi CHEN ZongMin YANG Xiao ZHANG ze YANG ZhenYu CAI JianXin School of Chemistry&Chemical Engineering Nanchang UniversityNanchang 330031China

The critical factors that limit the electrochemical performance of lithium-sulfur(Li-S)batteries are mainly the“shuttle effect”of polysulfides and the slow redox reaction between lithium polysulfides(LiPSs).Herein,a nano-sphere-type material selfassembled from tin disulfide nanosheets is designed and applied to the Li-S cell separator in this *** SnS_(2)@PP modified separator not only acts as a dual restriction for LiPSs by chemisorption and physical *** the same time,it improves the catalytic activity of the redox reaction between *** SnS_(2)has extremely high electrochemical ***,a portion of the lithium ions can be inserted into SnS_(2)to form Li_(x)SnS_(2)and contribute to the capacity during the first discharge of the *** addition,Li_(x)SnS_(2)possesses a high degree of stability,and it does not undergo further de-alloying reactions even at the high potential of the Li-S *** benefit is that the steady-state Li_(x)SnS_(2)acts as a lithium-containing *** can form special Li^(+)channels on the surface of the separator,thus greatly improving the efficiency of Li+*** results showed that the SnS_(2)@PP-based cell exhibited extremely high initial discharge specific capacity(1477 m Ah g^(-1)at 0.1 C)and excellent rate performance(631 m Ah g^(-1)at 5 C).Even after 1000 cycles at 2 C,the cell exhibited a low decay rate of 0.06%per cycle on *** addition,the superior electrochemical performance was obtained even with a high sulfur loading of 5.1 mg cm^(-2)and low electrolyte of E/S=8μL mg^(-1).

关键词： Li-S batteries modified separators polysulfides catalytic conversion high electrochemical activity

Chemical modification of barite for improving the performance of weighting materials for water-based drilling fluids

在线全文

学校读者我要写书评

暂无评论

Petroleum Science 2024年第1期21卷 551-566页

作者： Li-Li Yang ze-Yu Liu Shi-bo Wang Xian-Bo He Guan-Cheng Jiang Jie Zhang MOE Key Laboratory of Petroleum Engineering State Key Laboratory of Petroleum Resources and ProspectingChina University of Petroleum(Beijing)Changping DistrictBeijing102249China MOE Key CNPC Drilling Research Institute Changping DistrictBeijing102206China

With increasing drilling depth and large dosage of weighting materials,drilling fluids with high solid content are characterized by poor stability,high viscosity,large water loss,and thick mud cake,easier leading to reservoir damage and wellbore *** this paper,micronized barite(MB)was modified(mMB)by grafting with hydrophilic polymer onto the surface through the free radical polymerization to displace conventional API barite *** suspension stability of water-based drilling fluids(WBDFs)weighted with API barite:mMB=2:1 in 600 g was significantly enhanced compared with that with API barite/WBDFs,exhibiting the static sag factor within 0.54 and the whole stability index of *** viscosity and yield point reached the minimum,with a reduction of more than 40%compared with API barite only at the same *** multi-stage filling and dense accumulation of weighting materials and clays,filtration loss was decreased,mud cake quality was improved,and simultaneously it had great reservoir protection performance,and the permeability recovery rate reached 87%.In addition,it also effectively improved the lubricity of *** sticking coefficient of mud cake was reduced by 53.4%,and the friction coefficient was ***,mMB can serve as a versatile additive to control the density,rheology,filtration,and stability of WBDFs weighted with API barite,thus regulating comprehensive performance and achieving reservoir protection *** work opened up a new path for the productive drilling of extremely deep and intricate wells by providing an efficient method for managing the performance of high-density WBDFs.

关键词： Drilling fluids Weighting materials Filtration control Reservoir protection Stability property

Corrosion behavior of Al_(2)O_(3)-C bricks in MnO-containing mold slag

在线全文

学校读者我要写书评

暂无评论

Journal of Iron and Steel Research International 2024年第6期31卷 1486-1492页

作者： Yi-jiang Zhao Guang-qiang Li Yang Wu Cheng Yuan ze Meng Xiao-xuan Deng Yu Liu The State Key Laboratory of Refractories and Metallurgy Wuhan University of Science and TechnologyWuhan 430081HubeiChina Key Laboratory for Ferrous Metallurgy and Resources Utilization of Ministry of Education Wuhan University of Science and TechnologyWuhan 430081HubeiChina Hubei Provincial Key Laboratory for New Processes of Ironmaking and Steelmaking Wuhan University of Science and TechnologyWuhan 430081HubeiChina Research Institute of Technology Shougang Group Co.Ltd.Beijing 100043China

In order to explore the corrosion mechanism of Al_(2)O_(3)-C refractories in the mold flux bearing MnO,the immersion test of Al_(2)O_(3)-C refractories in CaO-SiO2-CaF2-MnO slag with different MnO contents was carried out at 1550℃.The results show that Mn particles were observed in the slag after experiment,due to the reduction of MnO by graphite in *** amounts of graphite were observed at the interface between refractories and slag,indicating that the oxidation of graphite is limited by the poor contact between graphite and molten ***,the oxidation of graphite is not the main cause of damage to refractories.A small quantity of CaO·2Al_(2)O_(3)(CA_(2))and CaO·6Al_(2)O_(3)(CA_(6))adjacent to Al_(2)O_(3) grain was detected at the slag/reaction layer ***_(2) and CA_(6) possess relatively high melting points,which is beneficial to hindering the further penetration of ***,the dissolution of Al_(2)O_(3) into slag is still the main cause for refractories *** increase in the MnO content of mold slag decreases the viscosity and then results in the severe corrosion of Al_(2)O_(3)-C bricks.

关键词： Al_(2)O_(3)-C refractory MnO-containing slag Graphite Corrosion

Sensing properties and mechanisms of LaF_(3)-Co_(3)O_(4) nanorods for low-concentration methanol detection

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Rare Metals 2024年第5期43卷 2193-2204页

作者： Xiao-Xi He Hong-Feng Chai Yi-Wen Zhou Ke-Wei Liu ze-Xin Yu Chao Zhang College of Mechanical Engineering Yangzhou UniversityYangzhou225127China Institutefor Manufacturing Technologies of Ceramic Components and Composites(IMTCCC) University of Stuttgart70569 StuttgartGermany

Methanol is one of the characteristic gases that distinguish between healthy individuals and lung cancer(LC)lesions in exhaled human *** concentration in exhaled breath is generally below one part per million(1×10^(-6)).The second-phase composite is widely regarded as one of the methods to improve the gas-sensing perfor-mance of metal oxide semiconductor(MOS)*** this study,LaF_(3)-Co_(3)O_(4) was synthesized by a simple hydrothermal method to enhance its low-concentration methanol gas-sensing performance.5 at%LaF_(3)-Co_(3)O_(4) nanorods exhibited excellent methanol detection performance,including a wider linear detection concentration range(0.2×10^(-6)~5×10^(-6)),a response value exceeding 4.0 for 1×10^(-6)methanol at 275°C and 75%relative humidity(RH),long-term stability(maximum deviation within 15%over 2 weeks),and excellent *** mechanism of performance enhancement was studied using various techniques,and density functional *** special spinel structure of Co_(3)O_(4),the high ionic migration of F-in LaF_(3),the larger specific surface area of 5 at%LaF_(3)-Co_(3)O_(4) nanorods,and the generated crystal defects all explain the excellentmethanol gas-sensing *** work provides a novel route to prepare MOS composite materials for low-concentration methanol gas detection.

关键词： Gas sensor LaF_(3) Co_(3)O_(4) Methanol Lung cancer

Toward high performance microwave absorber by implanting La_(0.8)CoO_(3)nanoparticles on rGO

在线全文

学校读者我要写书评

暂无评论

Journal of Materials Science & Technology 2024年第7期174卷 176-187页

作者： Li Chang Yu-ze Wang Xin-Ci Zhang Lin Li Hua-Zhang Zhai Mao-Sheng Cao Key Laboratory for Photonic and Electronic Bandgap Materials Ministry of EducationSchool of Physics&Electronic EngineeringHarbin Normal UniversityHarbin 150025China School of Materials Science and Engineering Beijing Institute of TechnologyBeijing 100081China

The advent of“intelligent era”brings our life more convenience,but the electromagnetic radiation sur-rounding us not only greatly threatens human health,also makes information leakage and hidden trouble to national defense ***,it is very urgent to develop novel electromagnetic wave absorption materials with lightweight,strong absorption,tunable absorption frequency and broad band ***,a novel electromagnetic wave absorber is obtained by constructing La_(0.8)CoO_(3)-rGO nanocompos-ite,where La_(0.8)CoO_(3)nanoparticles are anchored on graphene nanosheets by the electrostatic interaction between GO and La_(0.8)CoO_(3).The effect of hybridization ratio of La_(0.8)CoO_(3)and rGO on microwave ab-sorption properties is carefully *** optimal reflection loss of La_(0.8)CoO_(3)-rGO nanocomposite can reach-62.34 dB with the maximum effective bandwidth of 6.08 GHz,presenting 48.78%and 245.45%increment compared to bare La_(0.8)CoO_(3)nanoparticles,*** effective absorption bandwidth covers a broad electromagnetic wave absorption band from Ku band to the C band by tailoring thickness of the absorbers from 2.4 mm to 4.4 *** fascinating electromagnetic wave absorption performance is attributed to the synergy effect of La_(0.8)CoO_(3)and rGO,which integrates magnetic and dielectric loss caused by resonance,conductance,relaxation,and scattering *** result confirms that La_(0.8)CoO_(3)-rGO nanocomposite is potential candidates toward high-efficiency microwave absorbers and provides a valuable pathway for designing high-performance microwave attenuation materials in the future.

关键词： Perovskite La_(0.8)CoO_(3)nanoparticles Graphene Nanocomposite Microwave absorbing Broad band absorption

Design parameter optimization method for a prestressed steel structure driven by multi-factor coupling

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Frontiers of Structural and Civil Engineering 2024年第7期18卷 1066-1083页

作者： Guo-Liang SHI Zhan-Sheng LIU De-Chun LU Qing-Wen ZHANG Majid DEZHKAM ze-Qiang WANG Faculty of Architecture Civil and Transportation EngineeringBeijing University of TechnologyBeijing 100124China The Key Laboratory of Urban Security and Disaster Engineering of the Ministry of Education Beijing University of TechnologyBeijing 100124China Beijing Building Construction Research Institute Co. Ltd.Beijing 100039China

To achieve efficient structural design,it is crucial to reduce the cost of materials while ensuring structural *** study proposes an optimization method for design parameters(DPs)in a prestressed steel structure driven by multi-factor *** accomplish this,a numerical proxy model of prestressed steel structures is established with integration of DPs and mechanical parameters(MPs).A data association-parameter analysis-optimization selection system is established.A correlation between DPs and MPs is established using a back propagation(BP)neural *** correlation provides samples for parameter analysis and optimization *** are used to characterize the safety of the *** on the safety grade analysis,the key DPs that affect the mechanical properties of the structure are obtained.A mapping function is created to match the MPs and the key *** optimal structural DPs are obtained by setting structural materials as the optimization objective and safety energy as the constraint *** theoretical model is applied to an 80-m-span gymnasium and verified with a scale test physical *** MPs obtained using the proposed method are in good agreement with the experimental *** with the traditional design method,the design cycle can be shortened by more than 90%.Driven by the optimal selection method,a saving of more than 20% can be achieved through reduction of structural material ***,the cross-sectional dimensions of radial cables have a substantial influence on vertical *** initial tension and cross-sectional size of the upper radial cable exhibit the most pronounced impact on the stress distribution in that *** initial tension and cross-sectional size of the lower radial cable hold the greatest sway over the stress distribution in that cable.

关键词： structure design association relationship performance analysis optimum selection experimental verification

Supporting IrO_(x) nanosheets on hollow TiO_(2) for highly efficient acidic water splitting

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Nano Research 2024年第8期17卷 6903-6909页

作者： Ge Yu Ruilong Li Yanmin Hu Xingen Lin ze Lin Dongyang Wu Gongming Wang Xun Hong Center of Advanced Nanocatalysis(CAN) Department of Applied ChemistryUniversity of Science and Technology of ChinaHefei 230026China

The efficiency of proton exchange membrane water electrolysis(PEM-WE)for hydrogen production is heavily dependent on the noble metal iridium-based ***,the scarcity of iridium limits the large-scale application of *** address this issue,it is promising to select an appropriate support because it not only enhances the utilization efficiency of noble metals but also improves mass transport under high ***,we supported amorphous IrO_(x) nanosheets onto the hollow TiO_(2) sphere(denoted as IrO_(x)),which demonstrated excellent performance in acidic electrolytic water ***,the annealed IrO_(x)catalyst at 150℃in air exhibited a mass activity of 1347.5 A·gIr^(−1),which is much higher than that of commercial IrO_(2) of 12.33 A·gIr^(−1) at the overpotential of 300 mV for oxygen evolution reaction(OER).Meanwhile,the annealed IrO_(x) exhibited good stability for 600 h operating at 10 mA·cm^(−2).Moreover,when using IrO_(x) and annealed IrO_(x) catalysts for water splitting,a cell voltage as low as 1.485 V can be achieved at 10 mA·cm^(−2).The cell can continuously operate for 200 h with negligible degradation of performance.

关键词： oxygen evolution reaction hydrogen evolution reaction amorphous IrO_(x) hollow TiO_(2) proton exchange membrane water electrolysis