检索结果-南通市图书馆

维普期刊数据库博看期刊

Effect of screw casing structure on descending of burdens in COREX shaft furnace

在线全文

学校读者我要写书评

暂无评论

Journal of Iron and Steel Research International 2017年第1期24卷 18-26页

作者： Zi-long Qiu Zhi-guo Luo Heng Zhou Ren chen Feng Wang Zong-shu Zou College of Metallurgy Northeastern University College of Metallurgy Engineering Liaoning Institute of Science and Technology

COREX shaft furnace（SF）is a typical screw feeder with a storage container coupled with eight screw casings and *** structure of screw casing plays an important role in the moving behavior of burdens,stress distribution,abrasive wear of screws,and energy consumption during the operation of ***,a three-dimensional semi-cylindrical model of actual size of COREX-3000 SF was established based on discrete element method to investigate the influences of screw casing *** results show that the increase in the gap between the outside of screw flight and screw casing is beneficial for the smooth operation of SF,resulting in uniform descending velocity along the radius of SF in the lower part,decreasing the size of recirculation region,and alleviating stress concentration in the screw ***,raising the gap appropriately is also beneficial to weaken screw abrasive wear,decrease energy consumption,and then prolong the service life of the ***,enlarging the gap also leads to more undesired high temperature reduction gas into the SF from melter gasifier,thereby deteriorating the operation of ***,an ideal distance exists between the outside of the screw flight and the screw casing,which is suggested to be equal to the average of particle diameter.

关键词： COREX shaft furnace Screw casing structure Discrete element method Recirculation structure Screw abrasive wear

Morphological modification of Mg_(2)Si phase and strengthening mechanism in Mg_(2)Si/Al composites by Eu addition and T6 heat treatment

在线全文

学校读者我要写书评

暂无评论

Journal of Materials Science & Technology 2023年第28期159卷 151-162页

作者： Yinling Jin Hongze Fang Ruirun chen Jiwei Wang Shichen Sun shu Wang Bin Shao Jingjie guo National Key Laboratory for Precision Hot Processing of Metals Harbin Institute of TechnologyHarbin 150001China School of Materials Science and Engineering Harbin Institute of TechnologyHarbin 150001China

In order to improve mechanical properties of Mg_(2)Si/Al composites,Eu element was added to mod-ify Mg_(2)Si morphology,and T6 heat treatment was used to control Mg_(2)Si morphology and precipitate strengthening *** and morphology of Mg_(2)Si were observed by synchrotron X-ray to-mography and TEM,and first-principles calculations were also performed to testify the effect of Eu *** show that the size of primary Mg_(2)Si particles decreases and eutectic Mg_(2)Si phase trans-forms from lamellar to fibrous by Eu *** heat treatment,sharp angles of primary Mg_(2)Si par-ticles passivate,and eutectic Mg_(2)Si dissolves and appears to be short ***,nano-sizedβ"phase precipitates in the *** morphology of Mg_(2)Si with Eu modification,TEM results show that Eu impedes the growing of Mg_(2)Si,which is verified by first-principles calculations that Eu atom preferentially adsorbs on Mg_(2)Si{100}*** adsorption and suppression growing of Mg_(2)Si transform the morphology of Mg_(2)Si and thus improve the *** and elongation of the heat-treated Eu modified composites are 281 MPa and 8.4%,which improved 81%and 200%compared to the as-cast Al-15%Mg_(2)Si *** strengthening mechanism mainly results from precipitation strengthening of nano-sizedβ"precipitates in the heat-treated composite.

关键词： Mg_(2)Si/Al composites Modification Precipitate First-principles calculations Synchrotron X-ray tomography

Solute Distribution in Columnar Crystal Zone and Influences of Correlative Factors for Continuous Casting Slabs

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

Journal of Iron and Steel Research International 2008年第4期15卷 21-25页

作者： chen shu-ying CHANG guo-wei YUE Xu-dong WU Chun-jing School of Materials University of Science and Technology Beijing Beijing 100083 China College ofMaterial and Chemical Engineering Liaoning University of Technology Jinzhou 121000 Liaoning China

The expression of the solute distribution in columnar crystal zone was deduced when the solid-liquid interface bended periodically, and the quantitative calculations of macrosegregation were also made in the process of the continuous casting. The solute distribution along the thickness direction of the slabs was obtained, which verified the theoretical calculation. The effect of the bulge size, solidification speed, and solidification shrinkage speed on macrosegregation of the slabs was calculated. It can be concluded that normal segregation and negative segregation alternatively appear as a result of the bulge. The normal segregation exponentially depends on the bulge size, and the negative segregation linearly depends on the bulge size. The extent of the normal segregation is greater than that of the negative segregation when the bulge size is the same. The macrosegregation of the same position along the thickness direction of the slabs changes in a sine wave with increasing the solidification rate, and the amplitude is larger at the casting blank center. The normal segregation linearly decreases with increasing the solidification shrinkage speed, and when the solidification shrinkage speed exceeds a critical value, the segregation appears negatively and increases linearly.

关键词： continuous casting columnar crystal zone solute distribution macrosegregation

δ/δ Grain Boundary Movement in Fe-0.2%C-0.8%Cr During Solidification Process

在线全文

学校读者我要写书评

暂无评论

Journal of Iron and Steel Research International 2013年第6期20卷 63-67页

作者： YUE Xu-dong LI Qing-chun chen shu-ying CHANG guo-wei School of Materials Science and Engineering Liaoning University of Technology

The moving process ofδ / δgrain boundary during the solidification process of Fe-0.2%C-0.8%Cr has been observed in-situ with confocal scanning laser microscope （ CSLM ）, and the establishment of δ/δ grain boundary , the moving mode , the moving speed and the influence of correlative factor were explored in *** results showed that the clear grain cannot be formed when δ phase merged during solidification process of the steel if the actual cooling rate was 0.045℃·s-1 .The δ/δgrain boundary with shape of flat will be formed if there is no essential conjunction betweenδphase in a long period of *** movement ofδgrain boundary cross point drives other δ /δ grain boundaries to *** moving process is not stable , and the moving rate variation ranges from 0.12to 1.65 μ m ·s-1 .Temperature of the system is the chief factor for influencing the moving rate of δ / δgrain boundary during the *** the temperature fluctuation of system appears , the solidified grain boundary is re-melted , which results in the catastrophic fluctuation of moving rate for δ / δ grain *** the solidification process reaches its end , the average moving rate of δ /δ grain boundary is quicker than that of L / δ *** coarsening rate of crystal grain in the melt is slower than that of solidified solid phase crystal grain.

关键词： carbon steel solidification process δ / δ interface insitu observation

Modified technique in treating recurrent priapism： a technique report

在线全文

学校读者我要写书评

暂无评论

Asian Journal of Andrology 2015年第2期17卷 329-331页

作者： Wei chen shu-Ben Sun Li-An Sun Jian-Ming guo guo-Min Wang Department of Urology Zhongshan Hospital of Fudan University Shanghai China Department of Urology The Affiliated Hospital of School of Medicine of Ningbo University Ningbo China.

Recurrent ischemic priapism is a problem in clinical treatment. Most of the cases require more invasive surgery to shunt the blood stasis. We introduce a modified technique in treating recurrent ischemic priapism. The technique described is applied to acute ischaemic priapic episodes in patients with a history of stuttering priapism. It was carried out by a Winter＇s shunt combined with a continuous cavernosal irrigation system. Priapism was effectively resolved on the patients without recurrence. ]he four patients who received this treatment recovered most sexual function after 6 months follow-up.

关键词： @@

Pediatric living donor liver transplantation using liver allograft after ex vivo backtable resection of hemangioma: A case report

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

World Journal of Clinical Cases 2022年第12期10卷 3834-3841页

作者： shu-Xuan Li He-Nan Tang guo-Yue Lv Xuan chen Department of Hepatobiliary and Pancreatic Surgery the First Hospital of Jilin UniversityChangchun 130021Jilin ProvinceChina Department of Neurosurgery the First Hospital of Jilin UniversityChangchun 130021Jilin ProvinceChina

BACKGROUND Use of liver allograft with hepatic hemangioma after in vivo resection of hemangioma in living donor liver transplantation(LDLT)has been previously ***,there are few reports describing ex vivo backtable resection of hemangioma from liver allografts in *** SUMMARY A 55-year-old male was evaluated as a donor for an 8-month-year old patient with acute hepatic failure due to biliary ***-operative contrast enhanced computed tomography revealed a 9 cm hemangioma in segment 4 with vascular variations in the *** LDLT,an intra-operative intrahepatic cholangiography was performed to ensure no variation in the anatomy of the intrahepatic bile *** intra-operative pathological diagnosis,ex vivo backtable resection of the hemangioma was performed and the liver allograft was transplanted into the *** donor’s and recipient’s post-operative course were *** the 2-year follow-up,the liver allograft showed good regeneration without any recurrence of *** Liver allografts with hemangiomas are an acceptable alternative strategy for *** vivo backtable resection of hemangioma from the donor liver during pediatric LDLT is safe and feasible,and can effectively reduce the operative time and intra-operative bleeding for the donor.

关键词： Hemangioma Liver allograft ex vivo resection Backtable resection Pediatric living donor liver transplantation Case report

Inhibiting plastic tensile instability of non-symmetric thin-walled shell component via increasing regional metal inflow based on heterogeneous pressure-carrying medium

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 Journal of Aeronautics 2024年第1期37卷 391-413页

作者： Nan XIANG Yiquan shu Pengyi WANG Menghan YANG Haoran WANG Tao HUANG Junqing guo Fuxiao chen School of Materials Science and Engineering Henan University of Science and TechnologyLuoyang 471023China National Key Laboratory for Precision Heat Processing of Metals School of Materials Science and EngineeringHarbin Institute of TechnologyHarbin 150001China College of Mechanical&Electrical Engineering Shaanxi University of Science&TechnologyXi’an 710021China Provincial and Ministerial Co-construction of Collaborative Innovation Center for Non-ferrous Metal new Materials and Advanced Processing Technology Luoyang 471023China

Heterogeneous pressure-carrying medium was employed to establish a differentiated pressure field on sheet metal in flexible die forming process in this work,which aimed at matching the non-symmetric shape of target component and improving metal inflow to avoid local tensile ***,metal inflow corresponding to the differentiated pressure field was analytically *** of a typical non-symmetric shell component was experimentally and numerically studied based on the proposed *** with forming processes based on the uniform pressure,difference of metal inflow in two sides of the non-symmetric component increased from 2.16 mm to 3.36 mm and metal inflow in critical region increased by 11.9%when differentiated pressure field(taking heterogeneous elastomer#4–3 for example)was *** resultant maximum thinning ratio decreased by 4.2% and the uniformity of shell thickness increased by 16.9%.With the decrease of Shore hardness of elastomer in the formed region,stress path in the ready-to-form region transferred towards the bi-axial tension stress state,i.e.,stress ratio(a)***,stress triaxiality(η)in characteristic regions were regulated appropriately,which decreased the risk of tensile *** was attributed to the decreased normal pressure and frictional resistance at sheet/elastomer interface in the formed region.

关键词： Aluminum alloys Finite element method Metal forming Plastic deformation Sheet metal

Dense ceramics with complex shape fabricated by 3D printing:A review

在线全文

学校读者我要写书评

暂无评论

Journal of Advanced Ceramics 2021年第2期10卷 195-218页

作者： Zhe chen Xiaohong Sun Yunpeng Shang Kunzhou Xiong Zhongkai Xu Ruisong guo shu Cai Chunming Zheng School of Materials Science and Engineering Key Laboratory of Advanced Ceramics and Machining Technology of Ministry of EducationTianjin UniversityTianjin300072China School of Chemistry and Chemical Engineering State Key Laboratory of Hollow-fiber Membrane Materials and Membrane ProcessesTiangong UniversityTianjin300387China

Three-dimensional(3D)printing technology is becoming a promising method for fabricating highly complex ceramics owing to the arbitrary design and the infinite combination of *** density is one of the main problems with 3D printed ceramics,but concentrated descriptions of making dense ceramics are *** review specifically introduces the principles of the four 3D printing technologies and focuses on the parameters of each technology that affect the densification of 3D printed ceramics,such as the performance of raw materials and the interaction between energy and *** technical challenges and suggestions about how to achieve higher ceramic density are presented *** goal of the presented work is to comprehend the roles of critical parameters in the subsequent 3D printing process to prepare dense ceramics that can meet the practical applications.

关键词： 3D printing dense ceramics particle characteristics process parameters

Geographical discrimination of Cyclocarya paliurus tea for origin traceability based on multielement analysis by ICP-OES and chemometrics multivariate

在线全文

学校读者我要写书评

暂无评论

Chinese Herbal Medicines 2023年第1期15卷 63-68页

作者： Na guo Qi Wu chen Shi Rengeng shu School of Pharmacy Jiangxi University of Chinese MedicineNanchang 330004China

Objective: This paper focused on the geographical discrimination of Cyclocarya paliurus tea for origin traceability based on multielement analysis by ICP-OES and chemometrics ***: In this study, eleven trace element concentrations were determined by ICP-OES and processed by multivariate statistical ***: Based on ANOVA, the mean concentrations of 10 elements except Co differed significantly among six origins. Pearson’s correlation analysis showed that 11 pairs of elements have a positive significant correlation and 12 pairs have a negative significant correlation. The geographical origins were effectively differentiated using the eleven elements combined with PCA. And the S-LDA model offered a 100%differentiation ***: The overall results suggested that the combination of multielement analysis by ICP-OES and chemometrics multivariate could trace the geographical origins of tea. And the paper can provide reference for quality control and quality evaluation of C. paliurus in the future.

关键词： chemometrics multivariate Cyclocarya paliurus(Batal.)lljinskaja geographic origin multielement analysis ICP-OES