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Theoretical analysis of alloy multiplying factor by the empirical electron theory of solids and molecules

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Science china(Technological Sciences) 2007年第6期50卷 807-814页

作者： SONG YuePeng1,2. LIU GuoQuan2. LI ZhiLin3, FENG ChengMing1 1 Mechanical and Electronic Engineering college, Shandong Agricultural University, Tai’an 2.1018, china 2.college of Materials Science and Engineering, University of Science and technology, Beijing 100083, china 3 college of Material Science and Engineering, Beijing University of chemical technology, Beijing 10002., china Mechanical and Electronic Engineering college Shandong Agricultural University Tai’an China college of Materials Science and Engineering University of Science and Technology Beijing China college of Material Science and Engineering Beijing University of Chemical Technology Beijing China

By introducing the distribution probability of structural units in austenite contain- ing alloying elements and considering its effects on phase transformation, this paper establishes a calculation model of distribution probability of structural units. A new valence electron structure (VES) parameter-transformation effect coefficient of alloying elements (HL), is defined and then studied both theoretically and ex- perimentally. The relationship between the parameter HL and the multiplying factor (the quenching capability factor) of alloying elements is studied. The results indi- cate that the two parameters (HL and the quenching capability factor) have the same variation characteristic and substance feature. Therefore, the multiplying factor virtually expresses the relative quantity of structural units in the alloying elements-containing austenite.

关键词： multiplying factor (the quenching capability factor), empirical electron theory of solids and molecules, transformation effect coefficient of alloying elements, structural units in austenite containing alloying elements

咪唑(啉)-2.羧酸盐作为潜在的/可热活化的有机小分子催化剂催化转酯反应(英文)

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催化学报 2012年第3期33卷 502-507页

作者：王燕芹李振江南京工业大学生物与制药工程学院材料化学工程国家重点实验室江苏南京210009 南京林业大学理学院江苏南京210037

采用咪唑(啉)-2.羧酸盐(ImCO2.作为催化剂前驱体,通过温度控制脱除ImCO2.2.位羧酸根,再原位释放出高活性的N-杂环卡宾(NHCs),进而催化转酯反应.研究了NHCs在苯甲酸乙酯与一元醇、二元醇及氨基醇反应体系中的催化活性.结果表明,在该体... 详细信息

采用咪唑(啉)-2.羧酸盐(ImCO2.作为催化剂前驱体,通过温度控制脱除ImCO2.2.位羧酸根,再原位释放出高活性的N-杂环卡宾(NHCs),进而催化转酯反应.研究了NHCs在苯甲酸乙酯与一元醇、二元醇及氨基醇反应体系中的催化活性.结果表明,在该体系中不需要选用活化酯为原料,无需加入分子筛或加大醇酯比提高产率,仅用少量催化剂(0.5mol%),在较短时间内(3h),即可使反应转化率达到95%.

关键词： N-杂环卡宾有机小分子催化剂咪唑(啉)-2.羧酸盐转酯反应非活性酯

Some Invariant Properties of Semi-symmetric Metric Recurrent Connections and Curvature Tensor Expressions

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Chinese Quarterly Journal of Mathematics 2004年第4期19卷 355-361页

作者： ZHAO Pei-biao, SONG Hong-zao, YANG Xiao-ping(1. Department of Applied Mathematics, nanjing University of Science and technology, nanjing 2.0094, china 2. college of Mathematic and Information Science, Henan University , Kaifeng 475001, china) Department of Applied Mathematics Nanjing University of Science and Technology Nanjing 210094China college of Mathematic and Information Science Henan University Kaifeng 475001 China

The projective transformation of the special semi-symmetric metric recurrent connection is studied in this paper. First of all, an invariant under this transformation is granted; Secondly, by inducing of the invariant and making use of the properties that the corresponding covariant derivative keeps being fixed under the distinctness connection, the curvature tensor expression of the Riemannian manifold is posed at the same time.

关键词： projective transformation semi-symmetric metric connection metric recurrent connection invariant curvature tensor expression covariant derivative

Research on stability of the accumulated rock-soil body of reservoir bank under rainfall condition

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Science china(Technological Sciences) 2009年第9期52卷 2528-2535页

作者： GU ChongShi1,2.WU HaiZhen1,2.& SU HuaiZhi1,2.1 college of Water Resources and Hydropower Engineering,Hohai University,nanjing 2.0098,{2. 2.National Engineering Research Center of Water Resources Efficient Utilization and Engineering Safety,Hohai University,nanjing 2.0098,{2. 3 Jiangxi Water Conservancy Research Institute,Nanchang 33002.,{2. college of Water Resources and Hydropower Engineering Hohai University Nanjing China National Engineering Research Center of Water Resources Efficient Utilization and Engineering Safety Hohai University Nanjing China Jiangxi Water Conservancy Research Institute Nanchang China

The shear strength parameters property of rock-soil aggregates in embankment slope of reservoir,that is,the relationship between cohesion and gravel content,between friction angle and gravel content,and the relationship between cohesion and water content,between friction angle and water content,is studied based on the direct shear test results,the shear strength change law of the rock-soil aggregates is given,and the unsaturated shear strength formulation of rock-soil aggregates that could consider suction and saturation degree influence is put forward in this paper,through which the sliding or failure physical mechanism of this type of slope under the condition of rainfall infiltration is studied. Also the 3D unsteady saturated-unsaturated seepage field and its FEM resolving mode are established based on the analysis of the slope rainfall infiltration process. Case study with this method indicates that the minimum safety factor of the accumulated rock-soil aggregates dose not arrive at the moment of rainfall cessation,but appears several hours after the rainfall cessation,this phenomenon is in accordance with the practical slope engineering's failure process and could explain appropriately the slope failure caused by rainfall infiltration. Research results in this paper have an important reference value for the research on stability of the accumulated rock-soil aggregates in embankment slope of reservoir,and can enrich the stability analysis method and relevant theory of reservoir embankment slope.

关键词： reservoir bank slope rock-soil aggregates rainfall infiltration saturated/unsaturated seepage

Preparation and Properties of Crystallizable Glass/Al_2._3 Composites for LTCC Material

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Journal of Wuhan University of technology(Materials Science) 2011年第6期26卷 1174-1178页

作者：邵辉周洪庆 college of Materials Science and Engineering Nanjing University of Technology

The investigated low temperature Co fired ceramics（LTCC） composite of 60wt% CaO-Al2.3-B2.3-SiO2.glass and 40wt% α-Al2.3 as a filler is a non-reactive system, which is a critical part of the low temperature Co fired ceramics process. Through a study on densification process, the phase transformation and microstructure can be revealed. Its composites typically consist of CaO-Al2.3-B2.3-SiO2.glass and α-Al2.3 powders of average particle size （D50=3.49 mm）. The sintering behavior, phase evaluation, sintered morphology, and microwave dielectric properties were investigated. In the fire range of 800 to 900 ℃, the composites were crystallized after completion of densification. It is found that the composites start to densify at 82. ℃, simultaneously, the dielectric constant （εr） reaches its maximum. With increasing heat-treatment temperatures, due to the loose microstructure of the material, tanδ increases slightly. The last of the sintered samples were identified as partly Anorthite at 850 ℃. At that temperature it has εr of 7.9 and tanδ less than 1×10-3, and can be used as a promising LTCC material.

关键词： glass-ceramics densification precipitation LTCC materials

A new method of estimating the equivalent elastic modulus of RCCD

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Science china(Technological Sciences) 2007年第Z1期50卷 136-143页

作者： GU ChongShi1,2., WU Yuan1, SU HuaiZhi1,2.& TANG LiHui1 1 college of Water Conservancy and Hydropower Engineering, Hohai University, nanjing 2.0098, {2. 2.National Engineering Research Center of Water Resources Efficient Utilization and Engineering Safety, nanjing 2.0098, {2. college of Water Conservancy and Hydropower Engineering Hohai University Nanjing China National Engineering Research Center of Water Resources Efficient Utilization and Engineering Safety Nanjing China

Based on the composite material mechanic theory, the analysis method for the equivalent elastic moduli which are parallel and vertical to the construction interface of RCCD is studied in this paper. The differences between the equivalent elastic moduli which are vertical to the construction interface of RCCD gotten from different methods are discussed in detail. The variation range of the equivalent elastic modulus which is vertical to the construction interface of RCCD is studied based on the principle of minimum complementary energy and the principle of minimum potential energy. The effect of the related influential factors on the equivalent elastic modulus is analyzed. The estimation formula of the equivalent modulus which is vertical to the construction interface of RCCD is proposed. The feasibility of the approach proposed in this paper is analyzed through an example.

关键词： RCCD equivalent elastic modulus variation range estimation method

Review on hidden trouble detection and health diagnosis of hydraulic concrete structures

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Science china(Technological Sciences) 2007年第Z1期50卷 34-50页

作者： WU ZhongRu1,2., LI Ji1, GU ChongShi1,2.& SU HuaiZhi1,2.1 college of Water Conservancy and Hydropower Engineering, Hohai University, nanjing 2.0098, {2. 2.National Engineering Research Center of Water Resources Efficient Utilization and Engineering Safety, nanjing 2.0098, {2. college of Water Conservancy and Hydropower Engineering Hohai University Nanjing China National Engineering Research Center of Water Resources Efficient Utilization and Engineering Safety Nanjing China

A large number of hydraulic concrete structures have hidden defects such as cracks, erosion, freeze and thaw, thermal fatigue, carbonization. These hidden defects seriously affect the strength, stability and durability of structures. These problems are studied mainly by single monitoring or diagnosis methods at present. The integration of multiple monitoring and diagnosis methods is not applied widely. Besides, the analysis theory on these problems is not developed very well. The systemic study on the aging mechanism of hydraulic concrete structures, time- variation model and health diagnosis is still not enough. The support for engineering practice is limited. Aimed at these major scientific and technological problems and combined with specific projects, study on detection of hidden defects and health diagnosis of hydraulic concrete structure has been carried out. This study includes the following content: field non-destructive examination of hidden defects of hydraulic concrete structures, seepage detection, the construction of in-situ sensing system, the combination of field detection and in-situ monitoring, the mechanism of crack, freeze and thaw, erosion and carbonization of hydraulic concrete structure, mechanism of combination aging; time-variation model of hydraulic concrete structure, theories and methods for health diagnosis of hydraulic concrete structures.

关键词： hydraulic concrete structure hidden trouble detection health diagnosis

硅团簇的结构及生长模式——紧束缚分子动力学:Si_(11)—Si_(32.

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物理学报 2004年第2期53卷 592-595页

作者：刘玉真罗成林南京理工大学应用物理系南京210094 南京师范大学物理科学与技术学院南京210019

采用紧束缚分子动力学模拟硅团簇的结构 ,通过比较它们的结合能来确定基态结构 ,最后描绘出不同尺寸所对应的径向分布函数、角分布函数 .模拟表明硅团簇在n =2.7处发生结构转变 ,从结构图上看 ,是由扁长结构向近球形结构转变 .从径向分... 详细信息

采用紧束缚分子动力学模拟硅团簇的结构 ,通过比较它们的结合能来确定基态结构 ,最后描绘出不同尺寸所对应的径向分布函数、角分布函数 .模拟表明硅团簇在n =2.7处发生结构转变 ,从结构图上看 ,是由扁长结构向近球形结构转变 .从径向分布函数图像、键角分布函数图像上也可以得到团簇结构在n =2.7处发生了变化。

关键词：硅团簇紧束缚分子动力学模拟退火基态结构径向分布函数角分布函数扁长结构近球形结构键角分布函数

A Series Piezoelectric Quartz Crystal Response Kinetics for *** Growth in the Presence of Cu(Ⅱ)

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Journal of Central South University 2000年第1期12卷 15-19页

作者： CHAI Li yuan 1,2.,WEI Wan zhi 2.YAO Shou zhuo 2.1. Department of Metallurgical Science and Engineering, Central South University of technology, Changsha 410083, china 2. {2. of Chemistry and chemical Engineering, Hunan University, Changsha Department of Metallurgical Science and Engineering Central South University of Technology Changsha China college of Chemistry and chemical Engineering Hunan University Changsha China

The kinetics on the growth of *** in the presence of Cu(Ⅱ) was studied using of series piezoelectric quartz crystal (SPQC). Arsenic ion inhibits the growth of *** , which is consistent with the previous results by other measuring methods. This further demonstrates that the SPQC can monitor the chemical activity of *** growth. Cupric ion accelerates the growth of *** . The mechanism was discussed, i. e., copper promotes the protein enzyme of *** , rusticyanin, to form over the range of cupric ion concentration studied. The reaction order of cupric ion in accelerating the bacterial growth is 0.067. The growth of *** is dependent on temperature, the apparent reaction activation energy decreases from 2..56 kJ/mol to 18.32.kJ/mol because of the addition of 10 mg/L Cu(Ⅱ) to the bacterial growth solution of pH 2.0 at initial inoculum of 10%.

关键词： series piezoelectric quartz crystal T.ferrooxidans growth kinetics sigmoid curve cupric ion