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Journal of Materials Science & Technology 2002年第6期18卷 561-563页

作者： Gongxiong LIAO, Xigao JIAN and Jinyan WANGDepartment of Polymer Science, Dalian University of Technology, Dalian 116012, China Dalian Univ Technol Dept Polymer Sci Dalian 116012 Peoples R China

Phase behavior, thermal stability and rheological properties of the blends of poly(phthalazinone ether ketone) (PPEK) with bisphenol-A polycarbonate (pc) prepared by solution coprecipitation were studied using differential scanning calorimetry (DSC), Frourier-Transform IR spectroscopy (FT-IR), thermogravimetric analysis (TGA) and capillary rheometer. The DSC results indicated that PPEK/pc blends are almost immiscible in full compositions. FT-IR investigation showed that there were no apparent specific interactions between the constituent polymers. The blends keep excellent thermal stability and the addition of pc degrades the thermal stability of blends to some degree. The thermal degradation processes of the blends are much similar to that of pc. The studies on rheological properties of blends show that blending PPEK with pc is beneficial to reducing the melt viscosity and improving the appearance of PPEK.

关键词： Poly (aryl ether ketone) Phase behavior Thermal stability Rheology

Multivariate statistical methods and GIS based evaluation of the health risk potential and water quality due to arsenic pollution in the K?z?l?rmak River

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International Journal of Sediment Research 2022年第6期37卷 754-765页

作者： Hüseyin Cüce Erkan Kal?pc? Fikret Ustao?lu Ilknur Kaynar Volkan Baser Mustafa Türkmen Deparment of Geomatics Engineering Giresun University Department of Biology Giresun University Deparment of Environmental Engineering Nevsehir Hac? Bektas Veli University

The K?z?l?rmak River is Turkey?s longest(1,355 km) river and it is important since it constitutes the drinking and irrigation water source of the Central Anatolia Region. In the current study, the spatial distribution, effect on irrigation water quality, environmental pollution status, ecotoxicological and health risks as well as possible sources of 12 potential toxic elements?(PTEs)(manganese(Mn),aluminum(Al), arsenic(As), chromium(Cr), zinc(Zn), iron(Fe), nickel(Ni), cadmium(Cd), cobalt(Co),copper(Cu), mercury(Hg), and lead(Pb)) concentrations from surface water samples in the K?z?l?rmak River were analyzed by using geographical information systems(GIS) software, ecotoxicological indices,and multivariate statistical analysis. As a result of the current study, it was determined that the As concentration is above the World Health Organization(WHO) limit values, and, in terms of the 12 PTEs,there is slight heavy metal contamination in the river according to the Heavy Metal Pollution Index(HPI)and Heavy Metal Evaluation Index(HEI) values and there is a low level of pollution. The Hazard Quotient for ingestion(HQingestion) and Hazard Index(HI) values indicate that non-carcinogenic effects may *** to river water is likely to result in a low level of carcinogenic risk(CR) in adults, mainly due to the As concentration. The water at Sampling Station S3(131.79) cannot be used for drinking and is not suitable for consumption. According to the sodium percentage(Na%), Sodium Absorption Ratio(SAR),and Magnesium Hazard(MH) index results, river water is suitable for agricultural use.

关键词： Kızılırmak Water quality indexes Public health Arsenic pollution Multivariate statistical methods

THERMO-ELASTIC-PLASTIC RESPONSE AND OPTIMUM DESIGN OF CERAMIC-METAL FGMS-CYCLIC THERML LOADING PROBLEM

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Journal of Wuhan University of Technology(Materials Science) 1999年第2期14卷 8-17页

作者： Zhai, pc Zhang, QJ Yuan, RZ Wuhan Univ Technol State Key Lab Mat Synth & Proc Wuhan 430070 Peoples R China

The materials are made with a graded composition and microstructure in the thickness direction from the ceramic side to the metal side. The cyclic thermal loading and high temperasure gradient environment are simulated by heating the ceramic surface with a cyclic hear flux input and cooling the metal surface with a flowing liquid niterogen. The thermal and themo-elastic-plastic response of the materials is calculated using the isotropic hardening model and kinetic hardening model. Emphasis is placed on the response analysis under the different graded compositional distributions. Through the response analysis, the optimum design process of the graded composition under the dynamic case is established, which is bused on a unified viewpoint of the heat insulation property, thermal stress relaxation property and stress history feature.

关键词： functionally graded materials cyclic thermal loading thermal-elastic-plastic response

THERMAL AND THERMO-ELASTIC-PLASTIC RESPONSE OF CERAMIC-METAL FUNCTIONALLY GRADED MATERIALS—THERMAL SHOCK PROBLEM

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Acta Mechanica Solida Sinica 1997年第2期10卷 148-156页

作者： Zhai, pc Zhang, QJ Yuan, RZ WUHAN UNIV TECHNOL STATE KEY LAB MAT SYNTH & PROCWUHAN 430070PEOPLES R CHINA

The thermal and thermo-elastic-plastic response of newly developed ceramic-metal functionally graded materials under a thermal shock load is studied. The materials are heated at the ceramic surface with a sudden high-intensity heat flux input, and cooled at the metal surface with a flowing liquid nitrogen. Emphasis is placed on two aspects: (1) the influence of the graded composition of the materials on the temperature and stress response; and (2) the optimum design of the graded composition from a unified viewpoint of the heat insulation property and stress relaxation property. Moreover, a comparison between the thermoelastic stress and the thermo-elastic-plastic stress is also made to indicate the plasticity effect.

关键词： functionally graded materials thermal shock thermo-elastic-plastic response

A THEORY OF EFFECTIVE THERMAL CONDUCTIVITY FOR MATRIX-INCLUSION-MICROCRACK THREE-PHASE HETEROGENEOUS MATERIALS BASED ON MICROMECHANICS

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Acta Mechanica Solida Sinica 2000年第2期13卷 179-187页

作者： Zhang, QJ Zhai, pc Li, Y Wuhan Univ Technol State Key Lab Adv Technol Mat Synth & Proc Wuhan 430070 Peoples R China

The effective thermal conductivity of matrix-inclusion-microcrack three-phase heterogeneous materials is investigated with a self-consistent micromechanical method (SCM) and a random microstructure finite element method(RMFEM). In the SCM, microcracks are assumed to be randomly distributed and penny-shaped and inclusions to be spherical, the crack effect is accounted for by introducing a crack density parameter, the effective thermal conductivity is derived which relates the macroscopic behavior to the crack density parameter. In the RMFEM, the highly irregular microstructure of the heterogeneous media is accurately described, the interaction among the matrix-inclusion-microcracks is exactly treated, the inclusion shape effect and crack size effect are considered. A Ni/ZrO2 particulate composite material containing randomly distributed, penny-shaped cracks is examined as an example. The main results obtained are: (1) the effective thermal conductivity is sensitive to the crack density and exhibits essentially a linear relationship with the density parameter: (2) the inclusion shape has a significant effect on the effective thermal conductivity and a polygon-shaped inclusion is more effective in increasing or decreasing the effective thermal conductivity than a sphere-shaped one; and (3) the SCM and RMFEM are compared and the two methods give the same effective property in the case in which the matrix thermal conductivity A, is greater than the inclusion one lambda(2). In the inverse case of lambda(1) < lambda(2), the two methods as the as the inclusion volume fraction and crack density are low and differ as they are high. A reasonable explanation for the agreement and deviation between the two methods in the case of lambda(1) < lambda(2) is made.

关键词： effective thermal conductivity heterogeneous materials microcracks micromechanics

Transmission of the Ychromosome microdeletion to a baby boy conceived after in tracytoplasmic sperm injection

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Chinese Medical Journal 2001年第1期114卷 97-99页

作者： Tse JYM Yeung WSB Lau EYL Ng EHY Tam pc So WWK Tang MHY Lau ET Ho pc Department of Obstetrics and Gynecology The University of HongKongHongKongChina

Subfertility can be caused by acquired or genetic factors. Y chromosome microdeletion is one of the genetic factors associating with male infertility.1 Azoospermia factors (AZFa, AZFb and AZFc) have been mapped to different subregions in Yq11.2 So far, two gene families, RNA-binding motif (RBM) and deleted in azoospermia (DAZ) from interval 6, were proposed as candidate spermatogenesis genes for AZF.3,4 Recent studies demonstrated that microdeletions were detected at a frequency of 5% to 18% in the AZF region of oligospermic and azoospermic men.5-7 With the development of assisted reproductive technologies, particularly intracytoplasmic sperm injection (ICSI), these men can now father a child and the genetic abnormalities in defective spermatozoa could be transmitted to future offspring. To examine the possible transmission of the Y-chromosome microdeletion to the offspring via ICSI treatment, we performed both cytogenetic and molecular analyses of the Y chromosome on both an infertile patient with Y chromosome microdeletion and his offspring.

关键词： sperm

Crystal structure of Y14F trichosanthin

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Chinese Science Bulletin 1997年第16期42卷 1363-1366页

作者： Wu, S Yan, J Yao, HB Shaw, pc Dong, YC Chinese Acad Sci Inst Biophys Beijing 100101 Peoples R China Chinese Univ Hong Kong Dept Biochem Hong Kong Hong Kong Peoples R China

RIBOSOME inactivating proteins (RIPs) are one kind of protein toxin, which exists extensively in plants. Trichosanthin (TCS)is an important member of this family. The crystal structures of TCS and its homologous protein at high resolution have laid a solid foundation for the research of the relationship between its structure and function. Compared with

关键词： ribosome inactivating protein trichosanthin mutant.

Crystal structure of Q156A trichosanthin

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Chinese Science Bulletin 1997年第16期42卷 1366-1369页

作者： Dong, YC Zhu, YR Cheng, SH Li, JH Shaw, pc Chinese Acad Sci Inst Biophys Beijing 100101 Peoples R China Chinese Univ Hong Kong Dept Biochem Hong Kong Hong Kong Peoples R China

RIBOSOME inactivating proteins (RIPs) are a group of toxin with RNA N-glycosidase. It

关键词： mutant crystal structure trichosanthin.

Review for dynamic researches in civil engineering in recent years

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Science China(Technological Sciences) 2010年第5期53卷 1450-1452页

作者： XU ZhaoDong RC&pc Key Laboratory of Education Ministry,Southeast University,Nanjing 210096,China RC&pc Key Laboratory of Education Ministry Southeast University Nanjing China

Structure dynamic research is a hot field in civil *** involves in many challenge topics,such as dynamic analysis and tests under earthquake,wind or other dynamic *** paper introduces main dynamic researches in civil engineering in recent years,which will be classified into five aspects,especially for researches published in Science in China Series E:Technological Sciences.

关键词： civil engineering structures dynamic researches