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Preparation and bioactivity of sol-gel macroporous bioactive glass

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Journal of University of Science and Technology Beijing 2008年第3期15卷 290-296页

作者： Zhihua zhou Jianming Ruan Jianpeng Zou zhongcheng zhou State Key Laboratory for Powder Metallurgy Central South University Changsha 410083 China College of Chemistry and Chemical Engineering Hunan University of Science and Technology Xiangtan 411201 China

Bioactive glass is well known for its ability of bone regeneration, and sol-gel bioactive glass has many advantages compared with melt-derived bioactive glass. 3-D scaffold prepared by the sol-gel method is a promising substrate material for bone tissue engineering and large-scale bone repair. Porous sol-gel glass in the CaO-SiO2-P205 system with macropores larger than 100 μm was prepared by the addition of stearic acid as a pore former. The diameter of the pore created by the pore former varied from 100 to 300 μm. The formation of a hydroxyapatite layer on the glass was analyzed by studying the surface of the porous glass by scanning electron microscopy, energy dispersive spectroscopy, X-ray diffraction, and Raman spectra after they had been immersed in simulated body fluid （SBF） for some time, and the porous glass shows good bioactivity.

关键词： macroporous glass sol-gel in vitro bioactivity bone repair

3Cr17NiMo耐蚀塑料模具钢碳化物溶解及析出规律

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金属热处理 2024年第5期49卷 40-46页

作者：夏云峰周仲成雷晓娟于慎军内蒙古北方重工业集团有限公司特钢事业部内蒙古包头014033 中信重工机械股份有限公司铸锻分公司河南洛阳471000

采用JMatPro模拟计算软件及试验研究相结合的方式,对3Cr17NiMo耐蚀塑料模具钢的碳化物溶解和析出规律进行了研究。经试验分析表明,3 Cr17NiMo钢经1140℃奥氏体化后,在740~1040℃范围内等温,碳化物均首先于奥氏体晶界以细棒状或针状析出... 详细信息

采用JMatPro模拟计算软件及试验研究相结合的方式,对3Cr17NiMo耐蚀塑料模具钢的碳化物溶解和析出规律进行了研究。经试验分析表明,3 Cr17NiMo钢经1140℃奥氏体化后,在740~1040℃范围内等温,碳化物均首先于奥氏体晶界以细棒状或针状析出,并随温度降低逐渐长大形成明显的网状结构,而没有球化析出的现象。该钢中网状碳化物一旦形成,极难溶解和消除,当固溶温度为1100℃时,针状或棒状分布的碳化物才明显减少,随着固溶时间的延长,奥氏体晶粒逐渐趋于等轴晶分布,晶粒尺寸开始粗化,当固溶时间达到10 h以上时,由于出现了再结晶现象,晶粒反而细化。经过1100℃保温20~30 h+1060℃保温3 h两次固溶处理,可有效改善3Cr17NiMo钢中网状碳化物形态,均匀组织,细化晶粒,获得良好的组织形貌。

关键词：塑料模具钢碳化物固溶析出球化

Stabilization for boundary controlled cascaded heat-ODE system with time-dependent coefficient

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Stabilization for boundary controlled cascaded heat-ODE syst...

Rheological responses of fumed silica suspensions under steady and oscillatory shear

第26届中国控制与决策会议

作者： zhongcheng zhou School of Mathematics and Statistics Southwest University

ISBN: (纸本)9781479937066

In this paper, the stabilization of a cascaded heat-ODE system with time-dependent coefficient is discussed by choosing suitable backstepping transformation transferring the original heat-ODE system into an exponentially stable object system. We prove the existence of time-dependent kernels in forward and invertible transformation via successive approximation method, which is the novelty of the paper, at the same time, the exponential stability of closed-loop system is proved.

关键词： Stabilization cascaded heat-ODE time-dependent coefficient boundary control

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Science China(Technological Sciences) 2009年第4期52卷 910-915页

作者： YANG HaiLin RUAN JianMing ZOU JianPeng WU QiuMei zhou zhongcheng zhou ZhiHua State Key Laboratory of Powder Metallurgy Central South UniversityChangsha 410083China

Rheological experiments under steady and oscillatory shear were conducted for fumed silica suspen- sions in polyethylene glycol. Under steady shear the shear-thinning and thickening response were exhibited and the flow exponent N was determined. With the increase of concentration the flow exponent N showed a rapid increase, and it increased dramatically when the discontinuous shear-thickening took place. Oscillatory shear experiments were conducted at constant frequency and constant amplitude strain, respectively. The shear-thinning and the discontinuous shear-thickening behavior were observed under different constant frequencies from 10 to 80 rad/s. The correlation between complex modulus (G*) and sweep frequency (ω) was illuminated at γ =750%. It was found that the correlation between G* and ω could be fitted by equation: G*∝ωn. The indexes in shear-thinning region and shear-thickening were determined. The indexes were similar to some extent at shear-thinning region and increased dramati- cally to a much higher value when the shear-thickening occurred,especially at higher weight fractions. The behaviors can be qualitatively explained as follows: the shear-thinning owes to decrease of viscos- ity, which results from disruption of the aggregates; the cluster theory attributes the shear-thickening to the formation of metastable, flow induced clusters, which block the system.

关键词： fumed silica suspension shear-thickening steady shear dynamic oscillatory shear rheological response

挤压316H奥氏体不锈钢大口径管材的晶粒度控制

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金属热处理 2024年第4期49卷 168-174页

作者：贾晓斌秦瑞廷涂明金李媛媛胡永平周仲成北京科技大学新金属材料国家重点实验室北京100083 内蒙古北方重工业集团有限公司内蒙古包头014030 北京科技大学材料科学与工程学院北京100083

系统研究了不同变形量、变形速率、冷却方式、固溶处理温度对316H奥氏体不锈钢晶粒度的影响,并开展了挤压大口径316H奥氏体不锈钢工程化试制。结果表明,变形量越大,晶粒越细小,挤压变形量为80%时,挤压后的晶粒度可达4级以上;在相同变形... 详细信息

系统研究了不同变形量、变形速率、冷却方式、固溶处理温度对316H奥氏体不锈钢晶粒度的影响,并开展了挤压大口径316H奥氏体不锈钢工程化试制。结果表明,变形量越大,晶粒越细小,挤压变形量为80%时,挤压后的晶粒度可达4级以上;在相同变形速率情况下,试样的晶粒尺寸与冷却方式关系明显,水冷、空冷和3 min保温再空冷方式的晶粒尺寸依次增大;在相同的冷却速度条件下,变形速率越快,晶粒尺寸越细小,但随着冷却力度的减弱,晶粒尺寸差距逐渐减少。固溶处理温度对晶粒尺寸长大的作用远大于固溶时间的作用,成形后固溶处理对晶粒的均匀化起到一定的作用,但固溶温度过高会使晶粒迅速长大,固溶处理温度和保温时间应该控制在1050℃和40 min内。

关键词： 316H不锈钢晶粒度挤压温度变形量固溶温度

Synthesis and purification of trialkyl compounds of gallium and indium

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Rare Metals 2002年第1期21卷 1-6页

作者： SHU Wangen, zhou zhongcheng and LI Xiong Chemistry and Chemical Engineering College, Central South University, Changsha 410083, China Chemistry and Chemistry Engineering College Central South University Changsha 410083 Chemistry and Chemical Engineering College Central South University Changsha 410083

The The research progress in trialkyl compounds of gallium andindium was discussed from two aspect, one was the chemical synthesisof the compounds and the other was the purification of them. Thereare three synthesis routes be- ing reported in the first aspect, *** route staring form pure metal, the route starting from the puremetal trihalides, and the electrochemical route. In the secondaspect, the purifying methods of decomposition-distillation and zonerefining were reviewed.

关键词： trialkyl compounds gallium nd indium synthesis purification

Development and Application of the Amphibious Modulized Skid-mounted CTU

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石油机械 2012年第11期40卷 126-129页

作者： Cao Heping zhou zhongcheng Zhang Zhihai Jianghan Machinery Research Institute DRI CNPC

This paper mainly introduces the structural composition,operating principle,major technical parameters,design features and technical features of the amphibious modulized skid-mounted coiled tubing unit(CTU).It also describes the experimental condition of this unit and its application in Jidong *** unit has been successfully operated in Jidong Oilfield 30 *** maximum lifting or snubbing depth is 2,300 m;the velocity is 15 m/min;the manifold pressure is 20 MPa;the maximum deviation angle is 35.8°.It has successfully realized the modularization of the *** whole system uses an explosion-proof design,which achieves the second class of explosion-proof grade in the oilfield operation area,and gets the explosion-proof certificate and certification of the China Classification *** also obtains the marine operation *** paper has a certain referential significance for the CTU's design and research.

关键词：油气田石油开发工程项目石油机械

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油茶大苗造林技术

安徽林业科技 2024年第4期50卷 44-45页

作者：章承林廖家志周忠诚李春艳湖北生态工程职业技术学院湖北武汉430200 罗田县林业局湖北黄冈438699

近年来,油茶一直是中央财政林业科技推广示范项目的首推木本油料树种。采用大苗造林技术,油茶成活率显著提高,盛果期大大提前,茶农容易接受,无论是经济效益还是社会效益都是非常明显。本文总结了油茶造林地选择和整地、良种大苗选择、... 详细信息

近年来,油茶一直是中央财政林业科技推广示范项目的首推木本油料树种。采用大苗造林技术,油茶成活率显著提高,盛果期大大提前,茶农容易接受,无论是经济效益还是社会效益都是非常明显。本文总结了油茶造林地选择和整地、良种大苗选择、挖栽植穴、起苗装运、科学栽植、栽后管护等油茶大苗造林关键技术,旨在为油茶栽植提供借鉴和参考,促进油茶产业发展。

关键词：油茶大苗造林技术

新型系统性炎症指标对胰腺癌预后价值的研究进展

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肝胆胰外科杂志 2024年第7期36卷 441-444,F0003页

作者：朱明远陈徐艰吴斌周中成沈亦钰王兢嘉兴大学附属第二医院肝胆胰外科浙江嘉兴314099

胰腺癌与炎症关系密切,系统性炎症指标对预测胰腺癌患者预后具有重要价值。新型系统性炎症指标包括全身免疫-炎症指数(SII)、系统性炎症反应指数(SIRI)和系统性炎症得分(SIS)等指标对评估胰腺癌预后展现了潜在作用价值和应用前景。但这... 详细信息

胰腺癌与炎症关系密切,系统性炎症指标对预测胰腺癌患者预后具有重要价值。新型系统性炎症指标包括全身免疫-炎症指数(SII)、系统性炎症反应指数(SIRI)和系统性炎症得分(SIS)等指标对评估胰腺癌预后展现了潜在作用价值和应用前景。但这些炎症指标在实际临床应用中面临的挑战,如缺乏统一的截断值标准,预测效果受患者个体差异等因素的影响,目前的研究还不足以支持其完全取代传统肿瘤标志物CA199。

关键词：胰腺癌全身免疫-炎症指数全身炎症反应指数系统性炎症得分预后