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Mesoporous Si-MCM-48 membrane prepared by pore-filling method

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science china(Technological sciences) 2010年第4期53卷 1064-1068页

作者： XU DeKan & FAN YiQun State Key Laboratory of materials-Oriented chemical engineering,college of Chemistry and chemical engineering,Nanjing university of technology,Nanjing 210009,china 1. State Key Laboratory of materials-Oriented chemical engineering College of Chemistry and Chemical Engineering Nanjing University of Technology Nanjing 210009 China

Mesoporous MCM-48 membranes were prepared on asymmetric zirconia tubular support with an average pore size of 0.2 μm by hydrothermal *** support should be pretreated with H2O as a pore-filling substance to prevent the sol solution from infiltrating into the support *** SEM showed that the MCM-48 membrane was composed of tightly-connected spherical *** single gas N2 and H2 permeation experiments confirm that crack-free membrane could be prepared by pore-filling method.N2 permeance of MCM-48 membrane,synthesized by secondary growth,can reach 5.66×10-7 mol/Pa·s·m2,and the H2/N2 separation factor was 3.47 under trans-membrane pressure of 0.05 MPa.

关键词： MCM-48 mesoporous membrane pore-filling

Production of High Carbon Ferrochromium Using Melt Circulation

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International Journal of Minerals,Metallurgy and materials 1998年第4期12卷 192-202页

作者： Yulong Ding A J Merchant( Department of chemical engineering and chemical technology, Impenal college of science, technology and Medicine, Prince Consort RoadLondon SW7 2BY, UK)( School of chemical engineering of the university of Birmingham, Edgbaston, Department of chemical engineering and chemical technology Imperial College of Science Technology and Medicine Prince Consort Road London SW7 2BY United Kingdom School of chemical engineering University of Birmingham Edgbaston Birmingham B15 2TT United Kingdom

Some fundamental studies related to the production of high carbon ferrochromium were summarizedusing melt circulation technology carried out in the School of chemical engineering at the university of Birmingham. These studies focused on the kinetics of chromite reduction in Fe-C(-Cr-Si) melts. The effects of feed mode,fluxes, amount and particle size of reductant, particle size of chromite, melt composition and the reduction temperature were investigated. The reduction mechanisms were discussed. The results showed that (1 ) the reduction rates ofsintered chromite Pellets and non-compacted chromite powder in Fe-C(-Cr-Si) melts was generally very low,(2) addition of carbon in the non-compacted chromite feed greatly improved the reduction kinetics, (3) compaction of thecarbon-chromite mixtures into composite Pellets further improved the reduction kinetics and (4) addition of lime inthe composite Pellets increased the reduction rate, while the addition of silica may suppress the posihve effect oflime. It can be concluded that solid-state reduction, smelting reduction and dissolution proceed simultaneouslyduring the reduction of compacted compostite pellets or non-compacted composite mixtures in Fe-C(-Cr-Si) melts,and the early stage of reduction is very likely to be controlled by either or both solid-state and/or gas diffusionthrough the oxide phases and/or the product layers.

关键词： smelting reduction chromite reduction mechanisms ferrochromiumNomenclatures

Effects of NaNbO_3-Co_2O_3 Co-additive on the Properties of PZN-PZT Ceramics

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Journal of Wuhan university of technology(materials science) 2007年第4期22卷 722-724页

作者：邓毅华 college of material science and engineering South China University of Technology Department of Electronic science and technology Huazhong University of Science and TechnologyWuhan 430074China

NaNbO3-Co2O3 co-added PZN-PZT （PZCNNT） ceramics were prepared using conventional solid state reaction. The piezoelectric and dielectric properties were measured. The experimental results show that the addition of 0.3mo1% Co2O3 leads to low dielectric loss （tgδ） in PZCNNT ceramics and the proper addition of NaNbO3 not only improves piezoelectric properties but also decreases intensively dielectric loss and mechanical loss. The optimal ceramic having d33=310 pC/N, kp=0.59, εr=985, tgδ=0.0034, Qm=1380 was obtained.

关键词： PZN-PZT piezoelectric constant dielectric constant dielectric loss

Review on abort trajectory for manned lunar landing mission

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science china(Technological sciences) 2010年第10期53卷 2691-2698页

作者： XI XiaoNing1, HUANG WenDe2 & WANG Wei2,3 1 college of Mechatronics engineering and Automation, National university of Defense technology, Changsha 410073, china 2 college of Aerospace and material engineering, National university of Defense technology, Changsha 410073, china 3 School of Surveying and Spatial Information System, university of New South Wales, Sydney, NSW 2052, Australia 1. college of Mechatronics engineering and Automation National University of Defense Technology Changsha 410073 China2. College of Aerospace and Material Engineering National University of Defense Technology Changsha 410073 China3. School of Surveying and Spatial Information System University of New South Wales Sydney NSW 2052 Australia

Abort trajectory is a passage that ensures the astronauts to return safely to the earth when an emergency occurs. Firstly,the essential elements of mission abort are analyzed entirely based on summarizing the existing studies. Then,abort trajectory requirement and rational selection for different flight phases of typical manned lunar mission are discussed specifically. Considering a trade-off between the two primary constrains of an abort,the return time of flight and energy requirement,a general optimizing method for mission abort is proposed. Finally,some suggestions are given for china’s future manned lunar landing mission.

关键词： manned lunar landing mission abort trajectory design free return trajectory

Improved electrochemical performances of polyaniline nanotubes-poly-L-lysine composite for label-free impedance detection of DNA hybridization

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science china Chemistry 2010年第6期53卷 1371-1377页

作者： YANG Tao,JIANG Chen,ZHANG Wei & JIAO Kui Key Laboratory of Eco-chemical engineering,Ministry of Education college of Chemistry and Molecular engineering,Qingdao university of science and technology,Qingdao 266042,china 1. Key Laboratory of Eco-chemical engineering Ministry of Education college of Chemistry and Molecular engineering Qingdao University of Science and Technology Qingdao 266042 China

A sensitive label-free DNA hybridization biosensing platform was fabricated based on the synergistic effect of polyaniline nanotubes (PANInt) and poly-L-lysine (pLys).The composite of pLys and PANInt was coated onto the carbon paste electrode (CPE) to form a uniform and very stable nanocomposite *** pLys in the composite film not only acts as a membrane to retain good electron transfer capability of PANInt even at physiological pH,but also possesses fine biocompatibility for *** probes with negatively charged phosphate groups were readily linked to the positively charged pLys surface due to the strong electrostatic *** synergistic effect of PANInt and pLys could significantly enhance the sensitivity of DNA hybridization *** phosphinothricin acetyltransferase (PAT) gene fragment from transgenic corn and the polymerase chain reaction amplification of the terminator of nopaline synthase gene from the real sample of a kind of transgenic soybean were detected by this DNA electrochemical biosensor via label-free impedance *** stable composite gives convenient permselectivity properties as a transducer material for the design of modern electrochemical impedance biosensor using [Fe(CN)6]3-/4as an indicator.

关键词： poly-L-lysine polyaniline nanotubes DNA electrochemical biosensor PAT gene NOS gene

Oxidation-induced strengthening behavior of reaction formed Al_4SiC_4 ceramics

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Rare Metals 2007年第S1期26卷 94-98页

作者： HUANG Xiaoxiao1,2),WEN Guangwu1,3),LIU Ruitang2),and ZHENG Xin1)1) School of materials science and technology,Harbin Institute of technology,Harbin 150001,china 2) School of material science and chemical engineering,Harbin engineering university,Harbin 150001,china 3) School of materials science and technology,Harbin Institute of technology at Weihai,Weihai 264209,china Harbin Inst Technol Sch Mat Sci & Technol Harbin 150001 Peoples R China Harbin Inst Technol Sch Mat Sci & Chem Engn Harbin 150001 Peoples R China Harbin Inst Technol Sch Mat Sci & Technol Weihai 264209 Peoples R China

The bending strengths of Al4SiC4 ceramics were investigated from room temperature to 1300 ℃ in air and in vacuum,*** is a novel property that the bending strength increases with increasing test temperatures up to 1300 ℃ in *** strength value of Al4SiC4 ceramics is 449.7 MPa at 1300 ℃ in air,which is about 1.5 times of that at room temperature(300 MPa).The self-healing behavior of the flaws on the specimen surface due to the oxidation of the surface layer of the Al4SiC4 ceramics is considered as the main enhancement mechanism at high temperatures.

关键词： calcination and hot pressing surface strength Al_4SiC_4

Mining and Integrating Reliable Decision Rules for Imbalanced Cancer Gene Expression Data Sets

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Tsinghua science and technology 2012年第6期17卷 666-673页

作者： Hualong Yu 1 , Jun Ni 2 , Yuanyuan Dan 3 , Sen Xu 4 1. School of Computer science and engineering, Jiangsu university of science and technology, Zhenjiang 212003, china 2. Department of Radiology, Carver college of Medicine, The university of Iowa, Iowa City, IA 52242, USA 3. School of Biology and chemical engineering, Jiangsu university of science and technology, Zhenjiang 212003, china 4. School of Information engineering, Yancheng Institute of technology, Yancheng 224051, china School of Computer science and engineering Jiangsu University of Science and Technology Zhenjiang 212003 China|c|

There have been many skewed cancer gene expression datasets in the post-genomic era. Extraction of differential expression genes or construction of decision rules using these skewed datasets by traditional algorithms will seriously underestimate the performance of the minority class, leading to inaccurate diagnosis in clinical trails. This paper presents a skewed gene selection algorithm that introduces a weighted metric into the gene selection procedure. The extracted genes are paired as decision rules to distinguish both classes, with these decision rules then integrated into an ensemble learning framework by majority voting to recognize test examples; thus avoiding tedious data normalization and classifier construction. The mining and integrating of a few reliable decision rules gave higher or at least comparable classification performance than many traditional class imbalance learning algorithms on four benchmark imbalanced cancer gene expression datasets.

关键词： cancer gene expression data class imbalance paired differential expression genes decision ruleensemble learning majority voting

RTD-A控制器参数性能分析及在线模糊自整定

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上海交通大学学报 2011年第8期45卷 1167-1171页

作者：楚纪正杜彬陈娟北京化工大学信息科学与技术学院北京100029

为了减少RTD-A控制器的参数调节难度,增强其实用性,分析了RTD-A控制器中需要整定的4个参数,即系统鲁棒性θR、设定值跟踪θT、干扰抑制θD和全局收敛性θA对系统性能的影响.结果表明:当θT和θA在一定范围内取定值时,对系统控制结果不... 详细信息

为了减少RTD-A控制器的参数调节难度,增强其实用性,分析了RTD-A控制器中需要整定的4个参数,即系统鲁棒性θR、设定值跟踪θT、干扰抑制θD和全局收敛性θA对系统性能的影响.结果表明:当θT和θA在一定范围内取定值时,对系统控制结果不会产生明显的影响;而θR和θD的整定则能够改善系统模型失配和未知扰动等问题.为此,提出了一种基于模糊逻辑的控制器参数θR和θD的在线自整定方法.该方法首先建立了控制器参数的模糊控制规则,然后,根据模糊控制规则进行模糊推理,实现了参数θR和θD的在线模糊自整定.仿真实验结果表明,与手工设定参数方法相比,本文提出的参数在线模糊自整定方法能够简化参数的整定步骤,提高RTD-A控制器的性能.

关键词： RTD-A控制器模糊控制参数自整定

Surface tension of liquid Au-Bi-Sn alloys

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Rare Metals 2012年第3期31卷 250-254页

作者： Guo, Zhongnan Li, Shan Mikula, Adolf Yuan, Wenxia Department of Chemistry School of Chemical and Biological Engineering University of Science and Technology Beijing Beijing 100083 China Institute of Inorganic Chemistry/material Chemistry University of Vienna A-1090 Vienna Austria

The surface tension of a promising lead-free solder Au-Bi-Sn alloys was investigated both by the sessile-drop method and calculation. Experimental measurements were carried out for two cross-sections with the constant gold to bismuth ration of 1:1 and 1:2. For all the investigated compositions, decrease of the surface tension is observed with increasing temperature. Meanwhile, the surface tension values were also calculated based on Butler’s equation, with using the newest research on thermodynamics data of Au-Bi-Sn ternary system. Compared with the experimental results, a good agreement was obtained.

关键词： sessile-drop method Au-Bi-Sn alloys density surface tension Butler’s equation