检索结果-南通市图书馆

Evolution of microstructures and mechanical properties with tempering temperature of a pearlitic quenched and tempered steel

在线全文

学校读者我要写书评

暂无评论

Journal of Iron and Steel Research(International) 2022年第9期29卷 1393-1403页

作者： De-zhen Yang Zhi-ping Xiong Chao Zhang Guan-zheng Feng zhifang cheng Xing-wang cheng School of Materials Science and Engineering Beijing Institute of TechnologyBeijing 100081China National Key Laboratory of Science and Technology on Materials under Shock and Impact Beijing 100081China

Instead of conventional quenching and tempering,fast austenitization from an initial microstructure of lamellar pearlite followed by quenching and tempering was carried out,leading to the formation of inhomogeneous *** comprised different morphologies of lath martensite and retained austenite(RA).The effect of tempering temperature on microstructure evolution and tensile properties was systematically *** increasing tempering temperature from 150 to 250℃,transition carbides gradually coarsened and their amount increased,the dislocation density in martensitic laths gradually decreased,and RA fraction decreased from 10.9%to 2.2%.The precipitation and dislocation strengthening can ensure a high strength,while RA can ensure a good ductility,leading to a simultaneous increase in the strength and ductility when decreasing tempering ***,the best combination of tensile properties(ultimate tensile strength of 2133±41 MPa and total elongation of 11.1%±1.3%)was achieved after tempering at 150℃.

关键词： Fast austenitization Pearlite Tempering Manganese Mechanical property

Introduction to the Special Issue on Machine Learning-Guided Intelligent Modeling with Its Industrial 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

Computer Modeling in Engineering & Sciences 2024年第10期141卷 7-11页

作者： Xiong Luo Yongqiang cheng zhifang Liao School of Computer and Communication Engineering University of Science and Technology BeijingBeijing100083China Faculty of Technology University of SunderlandSunderlandSR60DDUK School of Computer Science and Engineering Central South UniversityChangsha410083China

With the advancement of Artificial Intelligence(AI)technology,traditional industrial systems are undergoing an intelligent transformation,bringing together advanced computing,communication and control technologies,Machine Learning(ML)-based intelligentmodelling has become a newparadigm for solving problems in the industrial domain[1–3].With numerous applications and diverse data types in the industrial domain,algorithmic and data-driven ML techniques can intelligently learn potential correlations between complex data and make efficient decisions while reducing human ***,in real-world application scenarios,existing algorithms may have a variety of limitations,such as small data volumes,small detection targets,low efficiency,and algorithmic gaps in specific application domains[4].Therefore,many new algorithms and strategies have been proposed to address the challenges in industrial applications[5–8].

关键词： Intelligence bringing intelligent

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

加工型辣椒种质资源遗传多样性分析

山东农业科学 2024年第1期56卷 34-42页

作者：韩娅楠行文妍史艳艳程志芳常晓轲董晓宇姚秋菊河南省农业科学院蔬菜研究所河南郑州450002 河南农业大学园艺学院河南郑州450002

为了解加工型辣椒种质资源的遗传多样性,本研究对33份加工型辣椒种质的24个农艺性状、8个品质性状和炭疽病抗性进行遗传多样性、相关性和聚类分析。结果表明,24个农艺性状中株幅、果梗长度、果肉厚的Shannon-Wiener多样性指数(H′)较大... 详细信息

为了解加工型辣椒种质资源的遗传多样性,本研究对33份加工型辣椒种质的24个农艺性状、8个品质性状和炭疽病抗性进行遗传多样性、相关性和聚类分析。结果表明,24个农艺性状中株幅、果梗长度、果肉厚的Shannon-Wiener多样性指数(H′)较大,性状遗传较丰富;单株产量变异系数最大(73.55%),心室数变异系数最小(9.18%)。单株产量与果肉厚、果纵径、果横径极显著正相关。8个品质性状中,辣椒素和二氢辣椒素含量的变异系数较大,分别为106.98%和112.44%。相关性分析表明,辣度与粗纤维和蛋白质含量显著正相关,与辣椒素和二氢辣椒素含量极显著正相关,与水分含量显著负相关。根据品质性状的隶属度将33份加工型辣椒种质聚为三大类群(Ⅰ、Ⅱ、Ⅲ),平均隶属度分别为0.32、0.47、0.64。炭疽病抗性与农艺、品质性状相关性分析表明,辣椒炭疽病抗性与水分含量、果纵径、心室数极显著正相关,与蛋白质、粗纤维含量极显著负相关。本研究结果可为加工型辣椒品种的应用及选育提供一定的理论依据。

关键词：加工型辣椒种质资源农艺性状品质性状遗传多样性

Switchable Multicomponent Cyclization Reactions to Access Fluoroalkylated Dihydropyrimidines and Pyrimidines under Solvent-Free Conditions

同方期刊数据库博看期刊评论

在线全文

学校读者我要写书评

暂无评论

Chinese Journal of Chemistry 2024年第12期42卷 1394-1398页

作者： Wanqing Zuo Zhizhen Zhu Yu cheng Lingling Zuo Xiao Geng zhifang Li Lei Wang College of Material Chemistry and Chemical Engineering Key Laboratory of Organosilicon Chemistry and Material TechnologyMinistryof EducationHangzhouNormal UniversityHangzhouZhejiang311121China Advanced Research Institute and School of Pharmaceutical Sciences Taizhou UniversityJiaojiangZhejiang 318000China state Key Laboratory of Organometallic Chemistry Shanghai Institute of Organic ChemistryChinese Academy of SciencesShanghai200032China

Comprehensive Summary The development of switchable solvent-free multicomponent reactions to build high-value-added products is an important demand for organic ***,we detailed the successful implementation of a switchable strategy for the construction of diverse 4-fluoroalkyl-1,4-dihydropyrimidines and 4-fluoroalkyl-pyrimidines via a solvent/additive-free[3+2+1]annulation,starting from readily available enamines,trifluoroacetaldehyde hydrate or 1-ethoxy-2,2-difluoroethanol and amidines *** reaction conforms to the concept of green synthesis,and provides a new avenue to access valuable fluorinated heterocycles.

关键词： Fluorine chemistry Multicomponent reactions Environmental chemistry Heterocycles Enaminones Amidines

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

河南省生姜产业发展现状、存在问题及建议

蔬菜 2024年第2期 10-14页

作者：董晓宇姚秋菊常晓轲韩娅楠程志芳史艳艳李丽河南省农业科学院蔬菜研究所河南郑州450002

为了进一步促进河南生姜产业发展,从种植面积及效益、种植模式、品牌建设、产区分布等方面梳理了河南生姜产业的发展现状,其中,生姜种植面积整体呈持续增长趋势,大多种植者采用露地种植,打造出了以清化姜、张良姜、黄姜、州姜为代表的... 详细信息

为了进一步促进河南生姜产业发展,从种植面积及效益、种植模式、品牌建设、产区分布等方面梳理了河南生姜产业的发展现状,其中,生姜种植面积整体呈持续增长趋势,大多种植者采用露地种植,打造出了以清化姜、张良姜、黄姜、州姜为代表的知名地方生姜品牌,形成了豫北、豫中和豫南3大主产区;并针对存在的机械化水平较低、市场竞争力缺乏、科研推广实力弱、价格变动大等问题,提出了加快良种选育和科技创新、加强品牌效应和打造全产业链等建议。

关键词：生姜产业发展现状建议

Triple reverse order law for the Drazin inverse

在线全文

学校读者我要写书评

暂无评论

Applied Mathematics(A Journal of Chinese Universities) 2024年第1期39卷 55-68页

作者： WANG Hua ZHONG cheng-cheng College of Sciences Inner Mongolia University of TechnologyHohhot 010051China College of Engineering University of Jinan Quancheng CollegeYantai 265600China

In this paper,we investigate the reverse order law for Drazin inverse of three bound-ed linear operators under some commutation ***,the Drazin invertibility of sum is also obtained for two bounded linear operators and... 详细信息

关键词： Drazin inverse reverse order law space decomposition

Photocatalytic activation of sulfite by N-doped porous biochar/MnFe_(2)O_(4) interface-driven catalyst for efficient degradation of tetracycline

在线全文

学校读者我要写书评

暂无评论

Green Energy & Environment 2024年第3期9卷 481-494页

作者： Long cheng Yuanhui Ji Jiangsu Province Hi-Tech Key Laboratory for Biomedical Research School of Chemistry and Chemical EngineeringSoutheast UniversityNanjing211189China

A novel photo-catalytic system composed of N-doped biochars(NBCs),MnFe_(2)O_(4) and sulfite activation under ultraviolet(NBCs/MnFe_(2)O_(4)/sulfite/UV)was constructed to realize the efficient eliminate of tetracycline(TC).As the carrier of MnFe_(2)O_(4),NBCs were synthesized from alfalfa,which has large specific surface area,graphite like structure and hierarchical porous *** adsorption isotherm indicated that NBCs/MnFe_(2)O_(4)-2:1 had the best adsorption performance for TC(347.56 mg g^(-1)).Through synergistic adsorption and photocatalysis,the removal rate of TC reached 84%,which was significantly higher than that of MnFe_(2)O_(4).Electrochemical impedance spectroscopy(EIS)and Photoluminescence(PL)characterization results showed that the introduction of NBCs improved the separation efficiency of photogenerated electron and hole pairs and enhanced the photocatalytic ***,the adsorption,degradation mechanism and degradation path of TC by the catalyst were systematically analyzed by coupling HPLC–MS measurement with the theoretical *** the advantages of excellent degradation performance,low cost,easy separation and environmental friendliness of NBCs/MnFe_(2)O_(4),this work was expected to provide a new path for the practical application of biochar.

关键词： Biochar MnFe_(2)O_(4) Sulfite Adsorption Photocatalysis

An improved initial rotor position estimation method using high-frequency pulsating voltage injection for PMSM

在线全文

学校读者我要写书评

暂无评论

Defence Technology（防务技术） 2024年第3期33卷 19-29页

作者： Yang Jiang Ming cheng School of Electrical Engineering Southeast UniversityNanjing 210096China

High frequency pulsating voltage injection method is a good candidate for detecting the initial rotor position of permanent magnet synchronous ***,traditional methods require a large number of filters,which leads to the deterioration of system stability and dynamic *** order to solve these problems,a new signal demodulation method is proposed in this *** proposed new method can directly obtain the amplitude of high-frequency current,thus eliminating the use of filters,improving system stability and dynamic performance and saving the work of adjusting filter *** addition,a new magnetic polarity detection method is proposed,which is robust to current measurement ***,experiments verify the effectiveness of the method.

关键词： Initial position detection Signal demodulation algorithm Magnetic polarity detection Filter elimination

Reliability of a Multicomponent Stress-strength Model Based on a Bivariate Kumaraswamy Distribution with Censored Data

在线全文

学校读者我要写书评

暂无评论

Acta Mathematicae Applicatae Sinica 2024年第2期40卷 478-507页

作者： Cong-hua cheng School of Mathematics and Statistics Zhaoqing UniversityZhaoqing 526061China

In this paper,we consider a system which has k statistically independent and identically distributed strength components and each component is constructed by a pair of statistically dependent elements with doubly type-II censored *** elements(X1,Y1),(X2,Y2),…,(Xk,Yk)follow a bivariate Kumaraswamy distribution and each element is exposed to a common random stress T which follows a Kumaraswamy *** system is regarded as operating only if at least s out of k(1≤s≤k)strength variables exceed the random *** multicomponent reliability of the system is given by Rs,k=P(at least s of the(Z1,…,Zk)exceed T)where Zi=min(Xi,Yi),i=1,…,*** Bayes estimates of Rs,k have been developed by using the Markov Chain Monte Carlo methods due to the lack of explicit *** uniformly minimum variance unbiased and exact Bayes estimates of Rs,k are obtained analytically when the common second shape parameter is *** asymptotic confidence interval and the highest probability density credible interval are constructed for Rs,*** reliability estimators are compared by using the estimated risks through Monte Carlo simulations.

关键词： stress-strength model bivariate Kumaraswamy distribution multicomponent reliability doubly Type-II censored scheme interval estimation