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DNA Modification with Photochromic Spiro Compounds

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Chinese Chemical Letters 2002年第4期13卷 299-302页

作者： pengzhang TeruoMatsuura 等 DepartmentofChemistry NankaiUniversityTianjin300071 EmeritusProfessor 21－26Kawashima－GondenchoSaikyokuKyoto615－8195Japan

The photochromic spiropyrans and spirooxazine having a succinimidyl ester or isothiocyanate pendant group can form covalent products with transaminated DNA. The absorption spectra and solid reflection spectra of modi... 详细信息

关键词： Photochromic spiro compound modification DNA.

A Novel Method for Quantification of Circulating DNA in Serum by Capillary Zone Electrophoresis

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Chinese Chemical Letters 2004年第9期15卷 1091-1094页

作者： pengzhang JiCunREN ZuoJunSHEN DepartmentofChemistry ShanghaiJiaotongUniversityShanghai200240 AnhuiProvincialHospital Hefei230001

In this paper, we first presented a novel method for quantification of circulating DNA in human serum based on capillary zone electrophoresis with laser-induced fluorescence detection (CZE-LIF). The serum was digested by proteinase to release free DNA, and then CZE-LIF system was used for the quantification of total circulating DNA. This method was successfully used to quantify the circulating DNA levels in sera from healthy individuals and certain cancer patients. We found the significantly elevated circulating DNA levels in certain prostate cancer patients. Our results demonstrated that CZE-LIF system has good linearity, excellent sensitivity (0.5 ng/mL DNA), satisfactory reproducibility (RSDs in one day and between days were both less than 5%) and reliability, and is well suitable to the quantification of the circulating DNA in human serum or plasma.

关键词： Circulating DNA capillary zone electrophoresis quantification serum.

Nonthermal Hawking radiation from NUT-Taub-like black hole

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Science China(Physics,Mechanics & Astronomy) 2012年第4期55卷 568-571页

作者： ZHAO GuoMing LI pengzhang College of Science Jilin Institute of Chemical TechnologyJilin 132022China

Using Damour-Ruffini method,we investigate Hawking radiation from NUT-Taub-like(NT-like) black *** the total energy conservation and the back reaction of the particle to the spacetime,we get the radiation spectrum on the black hole event horizon,which is related to the change of Bekenstein-Hawking ***,we find that the radiation is not exactly thermal,and can take out information from the black hole,which can be used to explain the information loss *** result that we get satisfies the unitary theory of quantum mechanics and is consistent with the work finished before.

关键词： Damour-Ruttini method NUT parameter Hawking radiation energy conservation

Semi-solid Pressing Bonding Strength between Steel and Cu-graphite Composite

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Journal of Materials Science & Technology 2005年第2期21卷 265-268页

作者： pengzhang YunhuiDU HanwuLIU DabenZENG JianzhongCUI LiminBA DepartmentofMechanicalEngineering NorthernJiaotongUniversityBeijing100044China DepartmentofMechanicalEngineering TsinghuaUniversityBeijing100084China DepartmentofMetalForming NortheastenUniversityShenyang110004China AnshanAutomobileFittingsFactory Anshan114014China

The pressing bonding of steel plate with QTi3.5-3.5graphite slurry was studied. The relationship among preheating temperature of steel plate, preheating temperature of dies, solid fraction of QTi3.5-3.5graphite slurry, and interfacial shear strength of bonding plate could be established with artificial neural networks perfectly. This model could be optimized with a genetic algorithm. The results show that the optimum bonding parameters are: 618℃ for preheating temperature of steel plate, 526℃ for preheating temperature of dies and 46.2% for solid fraction of QTi3.5-3.5graphite slurry, and the largest interfacial shear strength of bonding plate is 128.3 MPa.

关键词： Steel-mushy QTi3.5-3.5graphite bonding Artificial neural networks Genetic algorithm

Influence of Solid Fraction on Structure of QTi3.5-15/Graghite Slurry

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Journal of Materials Science & Technology 2004年第6期20卷 794-796页

作者： pengzhang YunhuiDU HanwuLIU DabenZENG dianzhongCUI LiminBA DepartmentofMechanicalEngineering BeijingJiaotongUniversityBeijing100044China DepartmentofMechanicalEngineering TsinghuaUniversityBeijing100084China MetalFormingDepartment NortheasternUniversityShenyang110006China AnshanAutomobileFittingsFactory Anshan114014China

The electromagnetic-mechanical stirring technology was used to prepare QTi3.5-15/graghite slurry. The distribution of graphite particies in QTi3.5-15/graghite slurry was studied using cold quenching method. The results show that solid fraction of QTi3.5-15/graphite slurry increases with the decreasing of stirring temperature. There is a linear relationship between solid fraction and stirring temperature. With the increasing of solid fraction, the distribution of graphite particies in slurry becomes uniform gradually. When the solid fraction is larger than 45%, the rising of graphite particies in slurry can be restricted, and QTi3.5-15/graghite slurry with uniform distribution of graphite particies can be prepared.

关键词： Copper alloy Electromagnetic stirring Composite Graphite particles

Study on Mechanical Property in Steel-Aluminum Solid to Liquid Bonding

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Journal of Materials Science & Technology 2003年第2期19卷 149-151页

作者： LizhongZHANC pengzhang YunhuiDU DabenZENG JianzhongCUI LiminBA DepartmentofMechanicalEngineering NorthernJiaotongUniversityBeijing100044China DepartmentofMechanicalEngineering TsinghuaUniversityBeijing100084China MetalFormingDepartment NortheastenUniversityShenyang110004China AnshanAutomobileFittingsFactory Anshan114014China

The bonding of solid steel plate to liquid Al was conducted using rapid solidification. The influence of thickness of Fe-Al compound layer at the interface on interfacial shear strength of bonding plate was studied. The results show that the relationship between thickness of Fe-AI compound layer and interfacial shear strength is 5=30.4+8.51 h-0.51 h2 +0.007 h3 (where h is thickness of Fe-AI compound layer, S is interfacial shear strength). When thickness of Fe-AI compound layer is 10.7 um, the largest interfacial shear strength is 71.6 MPa.

关键词： Mechanical property Rapid solidification Interface Interfacial shear strength

Interfacial Structure of Steel-Mushy Al-20Sn Bonding Plate

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Journal of Materials Science & Technology 2004年第2期20卷 193-195页

作者： pengzhang YunhuiDU HanwuLIU DabenZENG JianzhongCUI LiminBA DepartmentofMechanicalEngineering BeijingJiaotongUniversityBeijing100044China DepartmentofMechanicalEngineering TsinghuaUniversityBeijing100084China MetalFormingDepartment NortheasternUniversityShenyang110006China AnshanAutomobileFittingsFactory Anshan114014China

Fe-AI compound at the interface of steel-mushy AI-20Sn bonding plate was studied quantitatively. The relationship between ratio of Fe-AI compound at interface and bonding parameters (such as preheat temperature of steel plate, solid fraction of AI-20Sn slurry and rolling speed) was established by artificial neural networks perfectly. The results show that when the bonding parameters are 505℃ for preheat temperature of steel plate, 34.3% for solid fraction of AI-20Sn slurry and 10 mm/s for rolling speed, the reasonable ratio of Fe-AI compound corresponding to the largest interfacial shear strength of bonding plate is obtained. Its value is 72%. This reasonable ratio of Fe-AI compound is a quantitative criterion of interfacial embrittlement, that is, when the ratio of Fe-AI compound at interface is larger than 72%, interfacial embrittlement will occur.

关键词： Interfacial structure Fe-Al compound Artificial neural networks

Influence of Rolling Treatment on Interfacial Shear Strength of Steel-mushy Al-7graphite Bonding Plate

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Journal of Materials Science & Technology 2004年第6期20卷 694-696页

作者： pengzhang YunhuiDU HanwuLIU DabenZENG JianzhongCUI LiminBA DepartmentofMechanicalEngineering BeijingJiaotongUniversityBeijing100044China DepartmentofMechanicalEngineering TsinghuaUniversityBeijing100084China MetalFormingDepartment NortheastenUniversityShenyang110006China AnshanAutomobileFittingsFactory Anshan114014China

At room temperature, the rolling treatment of steel-mushy Al-7graphite bonding plate was carried out under different relative reduction. The influence of rolling on interfacial mechanical property of this bonding plate was studied. The results show that, for steel-mushy Al-7graphite bonding plate which is made up of 1.2 mm in thickness 08AI steel plate and 2.0 mm in thickness Al-7graphite layer, there is a nonlinear relationship between interfacial shear strength of bonding plate and relative reduction of rolling. When relative reduction of rolling is smaller than 2.59%, with the increasing of relative reduction, interfacial shear strength of bonding plate increases gradually. When relative reduction of rolling is bigger than 2.59%, with the increasing of relative reduction, interfacial shear strength of bonding plate decreases continuously. When relative reduction of rolling is 2.59%, the largest interfacial shear strength 77.0 MPa can be obtained.

关键词： Rolling treatment Relative reduction Interfacial shear strength

Interfacial mechanical property of steel-mushy Al-20Sn bonding

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Journal of University of Science and Technology Beijing 2004年第2期11卷 165-168页

作者： pengzhang YunhuiDu HanwuLiu DabenZeng JianzhongCui LiminBat DepartmentofMechanicalEngineering BeijingJiaotongUniversityBeijing100044China DepartmentofMechanicalEngineering TsinghuaUniversityBeijing100084China MetalFormingDepartment NortheasternUniversityShenyang110006China AnshanAutomobileFittingsFactory Anshan114014China

The bonding of a steel plate to Al-20Sn slurry was conducted using thecasting rolling technique. The surface of the steel plate was defatted, descaled, immersed (inK_2ZrF_6 flux aqueous solution) and stoved. Al-20Sn slurry was prepared using the electromagneticmechanical starring method. The interfacial mechanical property of the bonding plate was researchedto determine the relationship between the diffusion time and the interfacial shear strength. Inorder to identify the mechanism of bonding, the interfacial structure of the bonding plate wasstudied. The results show that at a prebeat temperature of the steel plate of 505 deg C and a solidfraction of Al-20Sn slurry of 35 percent, the relationship between the interfacial shear strength Sand the diffusion time t is S=28.8+4.3t-0.134t^2 +0.0011t^3. When the diffusion time is 22 s, thelargest interfacial shear strength is 70.3 MPa, and the corresponding interface is a new one whichis made up of Fe-Al compound and Fe-Al solid solution alternatively and in a right proportion. Inthis interfacial structure, the interfacial embrittlement does not happen and Fe-Al compound canplay its role in strong combination adequately.

关键词： interfacial shear strength diffusion time interfacial structure