检索结果-南通市图书馆

Description of martensitic transformation kinetics in Fe-C-X(X = Ni,Cr,Mn,Si) system by a modified model

在线全文

学校读者我要写书评

暂无评论

International Journal of Minerals,Metallurgy and Materials 2024年第5期31卷 1026-1036页

作者： Xiyuan Geng Hongcan Chen Jingjing Wang Yu Zhang Qun Luo Qian Li State Key Laboratory of Advanced Special Steels&shanghai Key Laboratory of Advanced Ferrometallurgy&School of Materials Science and Engineering Shanghai UniversityShanghai 200444China Ansteel Beijing Research Institute Co. LtdBeijing 102211China National Engineering Research Center for Magnesium Alloys Chongqing UniversityChongqing 400044China College of Materials Science and Engineering Chongqing UniversityChongqing 400044China National Key Laboratory of Advanced Casting Technologies Chongqing UniversityChongqing 400044China

Controlling the content of athermal martensite and retained austenite is important to improving the mechanical properties of high-strength steels,but a mechanism for the accurate description of martensitic transformation during the cooling process must be *** present,frequently used semi-empirical kinetics models suffer from huge errors at the beginning of transformation,and most of them fail to exhibit the sigmoidal shape characteristic of transformation *** describe the martensitic transformation process accurately,based on the Magee model,we introduced the changes in the nucleation activation energy of martensite with temperature,which led to the varying nucleation rates of this model during martensitic *** to the calculation results,the relative error of the modified model for the martensitic transformation kinetics curves of Fe-C-X(X = Ni,Cr,Mn,Si) alloys reached 9.5% compared with those measured via the thermal expansion *** relative error was approximately reduced by two-thirds compared with that of the Magee *** incorporation of nucleation activation energy into the kinetics model contributes to the improvement of its precision.

关键词： Fe-C-X system martensitic transformation kinetics curve semi-empirical model nucleation activation energy

Research on Bast Fiber Extracted from the White Bark of Three Species in the Genus Broussonetia

在线全文

学校读者我要写书评

暂无评论

Chinese Journal of Polymer Science 2024年第6期42卷 729-738页

作者： Shan-Shan Jin Si-Nong Wang Yan-Yan Huang Jing-Yu Zhang Peng Liu Hui Yu Hong-Dong Zhang Yu-Liang Yang Institute for Preservation and Conservation of Chinese Ancient Books Fudan University LibraryFudan UniversityShanghai200433China State key laboratory of Molecular Engineering of polymers Department of Macromolecular ScienceFudan UniversityShanghai200433China

Against the backdrop of a global paper resource shortage,there is a growing need to identify fast-growing tree species capable of producing long-lasting *** plant species namely Broussonetia kazinoki,Broussonetia papyrifera and hybrid paper mulberry,belong to the Broussonetia genus,were collected from china to study their white bark suitability for pulp and *** chemical composition revealed that the holocellulose content in Broussonetia kazinoki and Broussonetia papyrifera was more than 80%.The molecular weight distribution of several holocellulose/α-cellulose is observed by GPC,which allows us to better observe the changes of various components on the molecular *** yield,lignin,whiteness,and molecular weight of the pulps obtained by NaOH treatment were *** microscope was used to characterize the fiber length-width ratio and ***,the improvement of the fiber rigidity method based on the Kratky-Porod chain model makes it more theoretical and further reveals the influencing factors of fiber *** study demonstrates the high potentiality of these three species for papermaking applications.

关键词： Broussonetia genus Cellulose Alkaline pulping Kratky-Porod chain model Fiber rigidity

Experimental Investigation on Heat Transfer and Combustion of a Stirling Engine Combustor Fueled by Reformed Gas and Diesel Fuel

在线全文

学校读者我要写书评

暂无评论

Journal of Thermal Science 2024年第5期33卷 1907-1919页

作者： LAN Jian ZHAO Yanchun LIN Guangtao LI Yelin REN Zhe LYU Tian SHEN Mengmeng GU Genxiang HAN Dong Key Laboratory for Power Machinery and Engineering Ministry of EducationShanghai Jiao Tong UniversityShanghai200240China shanghai Marine Diesel Engine Research Institute Shanghai 201108China

Thermochemical recuperation heat recovery is an advanced waste heat utilization technology that can effectively recover exhaust waste heat from oxy-fuel Stirling *** novel combustor of a Stirling engine with thermochemical recuperation heat recovery system is expected to utilize both reformed gas and diesel fuels as sources of *** this research,the effects of various factors,including the H_(2)O addition,fuel distribution ratio(FDR),excess oxygen coefficient,and cyclone structure on the temperature distribution in the combustor,combustion emissions,and external combustion system efficiency of the Stirling engine were experimentally *** the increase of steam-to-carbon ratio(S/C),the temperature difference between the upper and lower heating tubes reduces and the circumferential temperature fluctuation decreases,and the combustion of diesel and reformed gas remains close to complete *** S/C=2,the external combustion efficiency is 80.6%,indicating a 1.6%decrease compared to conventional *** the increase of FDR,the temperature uniformity of the heater tube is improved,and the CO and HC emissions ***,the impact of the FDR on the maximum temperature difference and temperature fluctuation across the heater is *** the FDR rises from 21%to 38%,the external combustion efficiency increases from 87.4%to92.3%.The excess oxygen coefficient plays a secondary role in influencing temperature uniformity and temperature difference,and the reformed gas and diesel fuel can be burned efficiently at a low excess oxygen coefficient of *** an increase in the cyclone angle,the heater tube temperature increases,while the maximum temperature difference at the lower part decreases,and the temperature fluctuation ***,the CO and HC emissions increase,and the external combustion efficiency experiences a decrease.A cyclone angle of 30°is found to be an appropriate value for achieving optimal

关键词： Stirling engine fuel reforming synthetic gas oxy-combustion external combustion efficiency

An efficient parallel algorithm of variational nodal method for heterogeneous neutron transport problems

在线全文

学校读者我要写书评

暂无评论

Nuclear Science and Techniques 2024年第4期35卷 29-45页

作者： Han Yin Xiao-Jing Liu Teng-Fei Zhang School of Nuclear Science and Engineering Shanghai Jiao Tong UniversityShanghai 2002040China

The heterogeneous variational nodal method(HVNM)has emerged as a potential approach for solving high-fidelity neutron transport ***,achieving accurate results with HVNM in large-scale problems using high-fidelity models has been challenging due to the prohibitive computational *** paper presents an efficient parallel algorithm tailored for HVNM based on the Message Passing Interface *** algorithm evenly distributes the response matrix sets among processors during the matrix formation process,thus enabling independent construction without *** the formation tasks are completed,a collective operation merges and shares the matrix sets among the *** the solution process,the problem domain is decomposed into subdomains assigned to specific processors,and the red-black Gauss-Seidel iteration is employed within each subdomain to solve the response matrix ***-to-point communication is conducted between adjacent subdomains to exchange data along the *** accuracy and efficiency of the parallel algorithm are verified using the KAIST and JRR-3 test *** results obtained with multiple processors agree well with those obtained from Monte Carlo *** parallelization of HVNM results in eigenvalue errors of 31 pcm/-90 pcm and fission rate RMS errors of 1.22%/0.66%,respectively,for the 3D KAIST problem and the 3D JRR-3 *** addition,the parallel algorithm significantly reduces computation time,with an efficiency of 68.51% using 36 processors in the KAIST problem and 77.14% using 144 processors in the JRR-3 problem.

关键词： Neutron transport Variational nodal method Parallelization KAIST JRR-3

Wind Turbine Gearbox Fault Diagnosis Based on Multi-sensor Signals Fusion

在线全文

学校读者我要写书评

暂无评论

Protection and Control of Modern Power Systems 2024年第4期9卷 96-109页

作者： Yao Zhao Ziyu Song Dongdong Li Rongrong Qian Shunfu Lin the College of Electrical Engineering Shanghai University of Electric PowerShanghai 200090China IEEE the Design Research and Development Center AECC Commercial Aircraft Engine Co. Ltd.Shanghai 200241China

This paper proposes a novel fault diagnosis method by fusing the information from multi-sensor signals to improve the reliability of the conventional vibration-based wind turbine drivetrain gearbox fault diagnosis *** method fully extracts fault features for variable speed,insufficient samples,and strong noise scenarios that may occur in the actual operation of a wind turbine planetary ***,multiple sensor signals are added to the diagnostic model,and multiple stacked denoising auto-encoders are designed and improved to extract the fault ***,a cycle reservoir with regular jumps is introduced to fuse multidimensional fault information and output diagnostic results in response to the insufficient ability to process fused information by the conventional Softmax *** addition,the competitive swarm optimizer algorithm is introduced to address the challenge of obtaining the optimal combination of parameters in the ***,the validation results show that the proposed method can increase fault diagnostic accuracy and improve robustness.

关键词： Wind turbine gearbox fault diagnosis multiple scenarios deep learning stacked denoising au-to-encoder cycle reservoir with regular jumps feature fusion network

Alkali-resistant NO_(x) reduction over FeVO_(4)/TiO_(2)catalysts via regulating the electron transfer between Fe and V

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 Chemical Letters 2024年第2期35卷 489-495页

作者： Yunang Dong Penglu Wang Xiangyu Liu Jiang Deng Aling Chen Lupeng Han Dengsong Zhang International Joint Laboratory of Catalytic Chemistry State Key Laboratory of Advanced Special SteelCollege of SciencesShanghai UniversityShanghai 200444China

The presence of alkali metals in exhaust gas from stationary resources causes a grand challenge for the practical application of selective catalytic reduction(SCR)of NO_(x) with NH_(3).Here,alkali-resistant NO_(x) reduction has been successfully implemented via tailoring the electron transfer over Fe and V species on FeVO_(4)/TiO_(2)*** strong interaction between Fe and V induced electron transfer from V to Fe and strengthened the adsorption and activation of NH_(3)and NO over active VO_(x) *** the presence of K_(2)O,the strong electron withdrawing effect of Fe offset the electron donating effect of K on the VO_(x) species,thus protecting the active species VO_(x) to maintain the NO_(x) reduction *** enhanced adsorption and activation of NH_(3) allowed SCR reaction to proceed via E-R mechanism even after K_(2)O *** work elucidated the electronic effects on the alkali metals resistance of traditional ferric vanadate SCR catalysts and provided a promising strategy to design SCR catalysts with superior alkali resistance.

关键词： Air pollution control NO_(X)reduction Selective catalytic reduction Alkali metals Electron transfer

Spheroid construction strategies and application in 3D bioprinting

在线全文

学校读者我要写书评

暂无评论

Bio-Design and Manufacturing 2024年第5期7卷 800-818页

作者： Chunxiang Lu Chuang Gao Hao Qiao Yi Zhang Huazhen Liu Aoxiang Jin Yuanyuan Liu School of Mechatronic Engineering and Automation Shanghai UniversityShanghai 200444China School of Medicine Shanghai UniversityShanghai 200444China

Tissue engineering has been striving toward designing and producing natural and functional human *** are the fundamental building blocks of *** with traditional two-dimensional cultured cells,cell spheres are threedimensional(3D)structures that can naturally form complex cell–cell and cell–matrix *** structure is close to the natural environment of cells in living *** addition to being used in disease modeling and drug screening,spheroids have significant potential in tissue *** 3D bioprinting is an advanced biofabrication *** accurately deposits bioinks into predesigned 3D shapes to create complex tissue *** 3D bioprinting is efficient,the time required for cells to develop into complex tissue structures can be *** 3D bioprinting of spheroids significantly reduces the time required for their development into large tissues/organs during later cultivation stages by printing them with high cell *** spheroid fabrication and bioprinting technology should provide a new solution to many problems in regenerative *** paper systematically elaborates and analyzes the spheroid fabrication methods and 3D bioprinting strategies by introducing spheroids as building ***,we present the primary challenges faced by spheroid fabrication and 3D bioprinting with future requirements and some recommendations.

关键词： Spheroids Strategies 3D bioprinting Biofabrication

Synergistic effects of peroxydisulfate on UV/O_(3) process for tetracycline degradation:Mechanism and pathways

在线全文

学校读者我要写书评

暂无评论

Chinese Chemical Letters 2024年第10期35卷 408-413页

作者： Fengrui Yang Debing Wang Xinying Zhang Jie Zhang Zhichao Wu Qiaoying Wang State Key Laboratory of Pollution Control and Resource Reuse Shanghai Institute of Pollution Control and Ecological SecuritySchool of Environmental Science and EngineeringTongji UniversityShanghai 200092China Fujian Provincial Engineering Research Center of Rural Waste Recycling Technology College of Environment&Safety EngineeringFuzhou University.Fuzhou 350108China

Tetracycline(TC)as a typical emerging pollutant is becoming a serious threat to the environment and human health.A combined advanced oxidation technology of UV/Ozone(O_(3))/peroxydisulfate(PDS)process was developed to explore an efficient and economic treatment process of TC in ***,the reactive sites and transformation pathways of TC were explored and the toxicity of the intermediates was quantified with a quantitative structure-activity relationship(QSAR)*** degradation performance of TC was substantially enhanced in UV/O_(3)/PDS process with a kobsof 0.0949 min-1,which was 2.3 times higher than UV/O_(3)and 3.2 times than sole *** results demonstrated that there was a superior synergistic effect of PDS on UV/O_(3)processes for the degradation of *** paramagnetic resonance(EPR)analysis and quenching experiments show that·OH,SO_(4)·-,O_(2)·-and1O_(2)all contributed to TC degradation in the UV/O_(3)/PDS process and exhibited a synergistic effect,which inhibited the generation of harmful *** addition,the UV/O_(3)/PDS system can effectively degrade TC in a wide range of substrate concentrations and pH,and also showed excellent adaptability to various concentrations of anions(Cl-and HCO_(3)-).This study proves the feasibility of UV/O_(3)/PDS process for treating TC contaminated wastewater with complicated water matrix.

关键词： UV/ozonation/peroxydisulfate Synergistic effect Tetracycline Degradation Wastewater

Mechanisms of inclusion-induced pitting of stainless steels:A review

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1期168卷 143-156页

作者： Yangting Sun Xin Tan Rulei Lan Guoyong Ran Jin Li Yiming Jiang Department of Materials Science State Key Laboratory of Molecular Engineering of PolymersFudan UniversityShanghai 200438China

Pitting is a common type of localized corrosion in passive alloys that can cause rapid failure of material or *** the case of stainless steels,non-metallic inclusions have been identified as the most susceptible sites for pitting,and have therefore garnered significant *** review critically ex-amines the issue of how inclusions induce pitting,with a particular focus on three mechanisms:sponta-neous dissolution of inclusions,active dissolution of Cr-depleted regions,and propagation of microcracks at the inclusion-matrix *** researchers have made significant strides in understanding these mechanisms over the past few decades,many gaps and controversies *** such as the ini-tial driving force of inclusion dissolution and factors affecting Cr-depleted regions require further ***,some old concepts and methods need to be revised to arrive at more credible *** review aims to delve deeply into these important issues and provide inspiration for future research.

关键词： Pitting Inclusion Stainless steel Localized corrosion MnS