检索结果-南通市图书馆

Journal of Iron and Steel Research International 2023年第2期30卷 328-337页

作者： Xiao-hong Chu Peng-fei Gao Wei-jian Chen Feng Li Tao Kang Yan zhao Xian-dong Yin Zheng-zhi zhao Collaborative Innovation Center of Steel Technology University of Science and Technology BeijingBeijing100083China Beijing Laboratory for Modern Transportation Advanced Metal Materials and Processing Technology University of Science and Technology BeijingBeijing100083China Technical Center Shougang Jingtang United Iron and Steel Co.Ltd.Tangshan063200HebeiChina

The effects of Cr contents(0.3 and 1.0 wt.%)and isothermal holding temperatures(400,440,and 480℃)on the microstructure evolution and properties of complex phase steel with high formability(CH steel)were investigated using dilatometry,scanning electron microscopy,transmission electron microscopy(TEM),and X-ray *** results show that the microstructures of CH steel with 0.3 wt.%Cr are ferrite,granular bainite,martensite,and retained austenite,while no ferrite is observed in the microstructure of CH steel with 1.0 wt.%Cr in the same *** promotes the precipitation of(Nb,Ti)C in the high-temperature austenite region through theoretical calculations and TEM *** retards the bainite transformation and refines the grain size of CH ***,as isothermal holding temperature increases from 400 to 480℃,the bainite and retained austenite fractions of two CH steels decrease,while the martensite fraction increases in the steels after final ***,the strength has an increasing tendency and the total elongation has a decreasing tendency with increasing isothermal temperature.

关键词： Complex phase steel High formability steel CH steel Cr Isothermal holding temperature Microstructure Mechanical property

Improved macroscopic microscopic mass formula

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 C 2021年第7期45卷 247-253页

作者： Tian-Liang zhao Xiao-Jun Bao hong-fei Zhang School of Nuclear Science and Technology Lanzhou University730000 LanzhouChina Department of Physics Collaborative Innovation Center for Quantum Effectsand Key Laboratory of Low Dimensional Quantum Structures and Quantum Control of Ministry of EducationHunan Normal UniversityChangsha 410081China

A nuclear mass formula based on the macroscopic microscopic approach is proposed,in which the number of model parameters is reduced compared with other macroscopic microscopic *** root mean square(RMS)deviation with respect to 2314 training sets(measured nuclear masses)is reduced to 0.447 MeV,and the calculated value of each nucleus is no more than 0.8%different from the experimental *** single and two nucleon separation energies and the shell gaps are calculated to test the *** shell corrections and double magic number of superheavy nuclei are also analyzed.

关键词： macroscopic microscopic mass formula shell gap nucleon separation energy fission barrier single-particle energy level

Design strategies of high-performance lead-free electroceramics for energy storage applications

在线全文

学校读者我要写书评

暂无评论

Rare Metals 2024年第3期43卷 853-878页

作者： Biao Guo fei Jin Li Li Zi-zhao Pan Xin-Wei Xu hong Wang Department of Materials Science and Engineering College of EngineeringSouthern University of Science and TechnologyShenzhen518055China School of Microelectronics and State Key Laboratory for Mechanical Behavior of Materials Xi’an Jiaotong UniversityXi’an710049China

A greater number of compact and reliable electrostatic capacitors are in demand due to the Internet of Things boom and rapidly growing complex and integrated electronic systems,continuously promoting the development of high-energy-density ceramic-based *** significant successes have been achieved in obtaining high energy densities in lead-based ferroelectric ceramics,the utilization of lead-containing ceramies has been restricted due to environmental and health hazards of ***-free ferroelectric ceramics have garnered tremendous attention and are expected to replace lead-based ceramics in the near ***,the energy density of lead-free ceramics is still lagging behind that of lead-containing ***,severely limiting their *** efforts have been made to enhance the energy storage performance of lead-free ceramics using multi-scale design strategies,and exciting progress has been achieved in the past *** review briefly discusses the energy storage mechanism and fundamental characteristics of a dielectric capacitor,summarizes and compares the state-of-the-art design strategies for high-energy-density lead-free ceramics,and highlights several critical issues and requirements for industrial *** prospects and challenges of lead-free ceramics for energy storage applications are also discussed.

关键词： Dielectric materials Lead-free ceramic Environment friendly Energy storage Design strategy

Achieving Total Enteroscopy by Consecutive Bidirectional Doubleballoon Enteroscopy Procedures

在线全文

学校读者我要写书评

暂无评论

Current Medical Science 2022年第1期42卷 144-149页

作者： Liang zhao An-ning YIN fei LIAO Yi-juan DING hong-gang YU Department of Gastroenterology Renmin Hospital of Wuhan UniversityWuhan 430060China

Objective:To investigate the feasibility and safety of achieving total enteroscopy by consecutive bidirectional double-balloon enteroscopy(DBE)***:The demographic data,indication,initial insertion route,examination time for each insertion and the entire procedure,total enteroscopy rate,diagnostic yield and adverse events of patients who attempted to achieve total enteroscopy by consecutive bidirectional DBE procedures from January 2014 to December 2019 were retrospectively analyzed.

关键词： double-balloon enteroscopy feasibility safety total enteroscopy

Regioselective C-C bond cleavage/aminocarbonylation cascade under copper catalysis

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

Science China Chemistry 2024年第11期67卷 3798-3806页

作者： Qi-Chao Shan Yan zhao Yong Wu hong-fei Liu Xin-Hua Duan Li-Na Guo Department of Chemistry School of ChemistryEnergy Research Center of Energy Storage Materials and DevicesMinistry of EducationXi’an Jiaotong UniversityXi’an 710049China State Key Laboratory of Applied Organic Chemistry Lanzhou UniversityLanzhou 730000China

A regioselective C-C bond cleavage/aminocarbonylation cascade is presented. In recent years, tremendous progress has been made in the alkoxyl radical-mediated C-C bond cleavage of unstrained monocarbocycles. In contrast, the deconstruction and functionalization of bicyclic skeletons has been less developed and has mainly focused on the ring expansion process. Inspired by the aromatization-driven C-C bond cleavage, here we demonstrate a ring-opening/aminocarbonylation cascade under copper catalysis, in which the formation of a stable γ-lactam or succinimide skeleton reverses the selectivity of C-C cleavage. Remarkably, the photo and thermal assistance is not required when the succinimide skeleton is formed during the ring opening process. DFT calculations revealed that this unexpected ring-opening process is thermodynamically and kinetically favourable.

关键词： C-C bond cleavage controllable regioselectivity aminocarbonylation bicyclic alkoxy radical

Effects of three types of soil amendments on yield and soil nitrogen balance of maize–wheat rotation system in the Hetao Irrigation Area, China

在线全文

学校读者我要写书评

暂无评论

Journal of Arid Land 2019年第6期11卷 904-915页

作者： WU Yan LI fei ZHENG Haichun hong Mei HU Yuncai zhao Bayinnamula DE Haishan College of Grassland Resources and EnvironmentInner Mongolia Agricultural UniversityHohhot 010018China Inner Mongolia Key Laboratory of Soil Quality and Nutrient Resources Hohhot 010018China Soil and Fertilizer Station of Inner Mongolia Hohhot 010011China Department of Plant Sciences Technische Universität MünchenEmil-Ramann-Str.2D-85350 Freising-WeihenstephanGermany

Excessive fertilization combined with unreasonable irrigation in farmland of the Hetao Irrigation Area(HIR), China, has resulted in a large amount of nitrogen(N) losses and agricultural non-point source *** of soil amendments has become one of the important strategies for reducing N losses of ***, there is still no systematic study on the effects of various soil amendments on N losses in the *** this study, three types of soil amendments(biochar, bentonite and polyacrylamide) were applied in a maize–wheat rotation system in the HIR during 2015–*** of maize and wheat, soil NH3 volatilization, N2O emission and NO3– leaching were determined and soil N balance was *** results showed that applications of biochar, bentonite and polyacrylamide significantly increased yields of maize by 9.2%, 14.3% and 13.3%, respectively, and wheat by 9.2%, 16.6% and 12.3%, respectively, compared with the control(fertilization alone).Applications of biochar, bentonite and polyacrylamide significantly reduced soil N leaching by 23.1%, 35.5% and 27.1%, soil NH3-N volatilization by 34.8%, 52.7% and 37.8%, and soil N surplus by 23.9%, 37.4% and 30.6%, *** of bentonite and polyacrylamide significantly reduced N2O-N emissions from soil by 37.3% and 35.8%, respectively, compared with the *** with application of biochar, applications of bentonite and polyacrylamide increased yields of maize and wheat by 5.1% and 3.5%, *** results suggest that soil amendments(bentonite and polyacrylamide) can play important roles in reducing N losses and increasing yield for the maize–wheat rotation system in the HIR, China.

关键词： biochar bentonite polyacrylamide maize nitrogen loss nitrogen balance wheat

A sketch-based semantic retrieval approach for 3D CAD models

在线全文

学校读者我要写书评

暂无评论

Applied Mathematics(A Journal of Chinese Universities) 2017年第1期32卷 27-52页

作者： QIN fei-wei GAO Shu-ming YANG Xiao-ling BAI Jing zhao Qu-hong School of Computer Science and Technology Hangzhou Dianzi University State Key Laboratory of CAD&CG Zhejiang University School of Computer Science and Engineering Beifang University of Nationalities

During the new product development process, reusing the existing CAD models could avoid designing from scratch and decrease human cost. With the advent of big data,how to rapidly and efficiently find out suitable 3D CAD models for design reuse is taken more attention. Currently the sketch-based retrieval approach makes search more convenient, but its accuracy is not high enough; on the other hand, the semantic-based retrieval approach fully utilizes high level semantic information, and makes search much closer to engineers＇ ***, effectively extracting and representing semantic information from data sets is *** at these problems, we proposed a sketch-based semantic retrieval approach for reusing3 D CAD models. Firstly a fine granularity semantic descriptor is designed for representing 3D CAD models; Secondly, several heuristic rules are adopted to recognize 3D features from 2D sketch, and the correspondences between 3D feature and 2D loops are built; Finally, semantic and shape similarity measurements are combined together to match the input sketch to 3D CAD models. Hence the retrieval accuracy is improved. A sketch-based prototype system is *** results validate the feasibility and effectiveness of our proposed approach.

关键词： retrieval semantic sketch similarity descriptor recognize match rotation extracting circle

Wettability and corrosion behavior between alkaline slag from sodium smelting of vanadium-titanium magnetite and refractory substrates

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 1399-1410页

作者： fei zhao Zhi-wei Bian hong-xin zhao De-sheng Chen Zhang-fu Yuan Yu-lan Zhen Li-na Wang Tao Qi Collaborative Innovation Center of Steel Technology University of Science and Technology BeijingBeijing 100083China National Engineering Research Center of Green Recycling for Strategic Metal Resources Institute of Process EngineeringChinese Academy of SciencesBeijing 100190China Hebei Zhongke Tongchuang Vanadium&Titanium Technology Co. Ltd.Hengshui 053000HeheiChina

The sodium smelting of vanadium-titanium magnetite can achieve the comprehensive utilization of Fe,V,and ***,the generation of alkaline slag during this process may cause damage to refractory *** wettability and corrosion behavior of alkaline slag on three types of refractory(MgO-C,SiC,and high alumina refractory)substrates were investigated at temperatures up to 1200℃.The effects of duration on the wettability of molten slag on SiC substrates were also *** showed that the high alumina refractory exhibited better wettability with the molten slag than the others,and thus,it is easier to be *** results of scanning electron microscopy coupled with energy dispersive spectroscopy showed that MgO-C and high alumina refractory substrates were severely *** was a visible and regular interfacial reaction layer between the slag and SiC refractory substrate,which was produced by the redox reaction between the metal oxides in the slag and the SiC refractory *** the increase in holding time,the interface layer expands and silico-ferrite phases are generated at the *** redox reaction between Fe_(2)O_(3) and SiC substrate is the main reason for the *** comparing the differences in wettability and corrosion behavior between the alkaline slag from sodium smelting of vanadium-titanium magnetite and MgO-C,SiC and high alumina refractories,it is concluded that SiC refractory has good corrosion resistance to the *** oxides in the slag accelerate the oxidation rate of SiC refractory.

关键词： Wettability Corrosion Alkaline slag-Contact angle Vanadium-titanium magnetite Refractory

Gound State Properties of Nuclei in ^(295)118 α-Decay Chain

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

Communications in Theoretical Physics 2009年第12期52卷 1055-1061页

作者： DONG Jian-Min ZHANG hong-fei ZUO Wei WANG Yan-zhao LI Jun-Qing School of Nuclear Science and Technology Lanzhou University Lanzhou 730000 China Institute of Modern Physics Chinese Academy of Sciences Lanzhou 730000 China

The properties of nuclei belonging to the α-decay chain of superheavy element ^295118 have been studied in the framework of axially deformed relativistic mean field （RMF） theory with the parameter set of NL-Z2 in the blocked BCS approximation. Some ground state properties such as binding energies, deformations, and α-decay energies Qα have been obtained and agree well with those from finite-range droplet model （FRDM）. The single-particle spectra of nuclei in ^295118 α-decay chain show that the shell gaps present obviously nucleon number dependence. The root-mean-square （rms） radii of proton, neutron and matter distributions change slowly from ^283112 to ^295118 but dramatically from ^279110 to ^283112, which may be due to the subshell closure at Z = 110 in ^279110. The α-decay half-lives in 295118 decay chain are evaluated by employing the cluster model and the generalized liquid drop model （GLDM）, and the overall agreement is found when they are compared with the known experimental data. The α-decay lifetimes obtained from the cluster model are slightly larger than those of GLDM ones. Finally, we predict the α-decay half-lives of Z=118, 116, 114, 112 isotopes using the cluster model and GLDM, which also indicate these two models can corroborate each other in studies on superheavy nuclei. The results from GLDM are always lower than those obtained from the cluster model.

关键词： superheavy nuclei relativistic mean field half-lives cluster model generalized liquid drop model

Experimental study on the interfacial delamination in a thermal barrier coating system at elevated temperatures

在线全文

学校读者我要写书评

暂无评论

Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2010年第10期11卷 794-803页

作者： Peng-fei zhao Fu-lin SHANG Department of Engineering Mechanics School of Aerospace Xi 'an Jiaotong University Xi 'an 710049 China

The failure mode and adhesion of thermal barrier coating (TBC) 8YSZ (ZrO2+8% (w/w) Y2O3) deposited on NiCoCrAlTaY bond coat by atmospheric plasma spraying were investigated. A grooved modified three-point bending specimen that can generate a single interface crack to facilitate the control of crack growth was adopted for testing, which was conducted at the ambient temperature of 100 °C. The morphology and composition of fractured surfaces were examined by means of a scanning electron microscopy (SEM) and an energy disperse spectroscopy (EDS). Images and spectrum show that cracks are initiated and propagated exclusively within YSZ layer adjacent to top/bond coat interface. The load-displacement curves obtained exhibit similar shapes that indicate two distinct stages in crack initiation and stable crack growth. Finite element analyses were performed to extract the adhesion strength of the TBCs. The delamination toughness of the plasma-sprayed 8YSZ coatings at 100 °C, in terms of critical strain energy release rate Gc, can be reliably obtained from an analytical solution.

关键词： Thermal barrier coating (TBC) Three-point bending test Finite element analysis Delamination toughness