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The silt stalactite——a peculiar kind of sedimentary structures

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Chinese Science Bulletin 1997年第23期42卷 1974-1977,2025页

作者： Zhong, JH Ma, zp Univ Petr China Dongying 257062 Peoples R China

THE Yellow River, with its huge amount of silt charge from the Loess Plateau, is the secondlargest river in China. Its lower reach has become a famous hanging river because of serioussilting up, and the magnitude of discharge changes much from season to season. As a result ofsilting, migration of the stream channel happens frequently. Lateral erosion of channel or pointbars, and scarp slopes forming during the erosion may be often observed. The silt stalactite,hitherto not reported, usually forms on surfaces of the slope. As a newly found kind of sedirnen-tary structure, the silt stalactite may have some significance to the study of sedimentary envi-ronments and paleoclimate.

关键词： silt stalactite sedimentary structure the Yellow River Delta.

ELASTIC WAVES IN 3-D DISCRETE GRIDS

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Acta Mechanica Solida Sinica 1995年第4期8卷 283-293页

作者： Guan, HM Liao, zp INST ENGN MECH HARBIN 150080PEOPLES R CHINA

Wave motion in finite element models presents some characteristics different from those of wave motion in continuum, which leads to the errors and other special phenomena in finite element simulation of wave motion. The wave propagation in a 3-D finite element model is studied by utilizing the formal solution in the paper, and the corresponding dispersion relations are derived. Then the main properties of wave motion in 3-D grids such as dispersion, cut-off frequency and polarization drift are discussed. Characteristics different from those of wave motion in 2-D grids are revealed.

关键词： finite elements discrete grids 3-dimensional wave motion

A MODIFIED THERMAL VISCOPLASTIC CONSTITUTIVE LAW INVOLVING THE EFFECT OF TEMPERATURE RISE RATE

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Acta Mechanica Solida Sinica 2000年第2期13卷 141-148页

作者： Huang, CG Duan, zp Chinese Acad Sci Inst Mech LNM Beijing 100080 Peoples R China

At high temperature rise rate, the mechanical properties of 10 # steel were determined experimentally in a very wide range of temperature and strain rates. A new constitutive relationship was put forward, which can fit with the experimental results and describe various phenomena observed in our experiments. Meanwhile, some interesting characteristics about the temperature rise rate, strain and strain rate hardening and thermal softening are also shown in this paper. Finally, the reliability of the constitutive law and the correctness of the constitutive parameters were verified by comparing the calculation results with the experimental data.

关键词： constitutive law strain rate temperature rise rate

Stochastic Response Analysis of Piled Offshore Platform Excited by Stationary Filtered White Noise

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China Ocean Engineering 1997年第1期12卷 29-42页

作者： Luo, CX Wu, zp Institute of Offshore Engineering Tianjin University Tianjin 300072 China

In this paper, the analysis method of stochastic response of piled offshore platform excited by stationary filtered white noise is presented. With this method, the strong ground motion is considered as three direction stationary filtered white noise process, the theoretic solutions of three special integration equations are derived with the residue theorem, and the expression of response nodal displacements and member forces of offshore platform excited by the stationary filtered white noise is put forward. The stochastic response of a piled offshore platform excited by the stationary filtered white noise, which is located 114.3 m in water depth, is computed. The results are compared with those obtained with the response spectrum analysis method and the stationary white noise model analysis method, and the corresponding conclusion is drawn.

关键词： stochastic response piled offshore platform stationary filtered white noise stochastic model response spectrum

Immunocytochemical identification and localization of APUD cells in the gut of seven stomachless teleost fishes

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World Journal of Gastroenterology 2000年第1期6卷 96-101页

作者： Pan QS Fang zp Zhao YX College of Fisheries Huazhong Agricultural UniversityWuhan 430070Hubei ProvinceChina College of Animal Husbandry and Veterinary Medicine Huazhong Agricultural UniversityWuhan 430070Hubei ProvinceChina

AIM To study the cell types,localization,distribution density and morphology of APUDcells in the intestinal mucosa of stomachlessteleost *** By using the peroxidase-antiperoxidase complex(PAP)immunocytochemical staining technique theidentification,localization and morphology ofimmunoreactive(IR)endocrine cells seattered inthe intestinal mucosa of grass carp(Cyenopharyngodon idellus),black carp(Mylopharyngodon piceus)and common carp(Cyprinus carpio)were investigated with 20kinds of antisera prepared against mammalianpeptide hormones of APUD cells,and likewise byusing avidin-biotin-peroxidase complex(ABC)method those of silver carp(Hypophthalmichthys molitrix),bighead(Aristichthys nobilis),silver crucian carp(Carassius gibelio)and bluntnose black bream(Megalobrama amblyocephala)were alsostudied with 5 different *** of the first antiserum by phosphatebuffered saline(PBS)was employed as a *** endocrine cells were counted with asquare-mesh ocular micrometer from 10 fieldsselected randomly in every section of each partof the intestine *** average numberof IR endocrine cells per mm2 was counted toquantify their distribution *** Gastrin(GAS)-,Gastric inhibitorypeptide(GIP)-,glucagon(GLU)-,glucagon-likeimmunoreactants(GLI)-,bovine pancreaticpolypeptide(BPP)-,leucine-enkephalin(ENK)-and substance P(SP)-IR endocrine cells werefound in the gut of grass carp,black carp andcommon carp,and somatostatin(SOM)-IRendocrine cells were only seen in common ***-,GIP-and GLU-IR endocrine cells werefound in the intestinal mucosa of silver carp,bighead,silver crucian carp and bluntnose *** of IR endocrine cells had the higherdistribution density in the foregut and midgut,and were longer in *** had a long apicalcytoplasmic process extended to the gut lumenand a basal process extended to adjacent cellsor basement membrane and touched with ***,the basal cytoplasmic processformed an enlarged synapse-like st

关键词： Subject headings stomachless teleost fishes APUD cells intestinal mucosa immunocytochemistry

Structure Based Library Approach to Photosynthesis Inhibitors:The Solid Phase Synthesis of Hydro-Uracils and Thiouracils

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Chinese Chemical Letters 1998年第2期9卷 139-142页

作者： Yu, AM Yang, HZ Zhang, zp Nankai Univ State Key Lab Elementoorgan Chem Tianjin 300071 Peoples R China Nankai Univ State Key Lab Funct Polymer Mat Adsorpt & Separat Tianjin 300071 Peoples R China

A general method for the solid phase synthesis of hydro-uracils and thiouracils is described. Resino ester 2 reacts with various primary amines to give secondary amines 3, which are converted to the resino ureas (thioureas) 4 by treatment with isocyanates (isothiocyanates). Preparation of the hydro-uracils and thiouracils 5 is achieved by acidic cyclization-cleavage from the resin. The synthesis is designed to be amenable for structure based library approach to photosystem II D1 protein inhibitors.

关键词： solid phase synthesis hydro-uracils and thiouracils photosynthesis inhibitors

DETERMINATION OF EFFECTIVE MODULI FOR FOAM PLASTICS BASED ON THREE PHASE SPHEROIDAL MODEL

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Acta Mechanica Solida Sinica 1995年第4期8卷 294-302页

作者： Lu, ZX Huang, zp Wang, R BEIJING UNIV AERONAUT & ASTRONAUT INST SOLID MECHBEIJING 100083PEOPLES R CHINA BEIJING UNIV DEPT MECHBEIJING 100871PEOPLES R CHINA

The relations of bulk modulus, shear modulus, Young's modulus and the Poisson's ratio with porosity of foam plastics are determined by a three phase spheroidal model commonly used in Composite Mechanics. The results are compared with those using differential scheme. It is shown that the material properties derived from the present model normally are larger than those obtained by differential scheme for foam plastics with identical porosity. The differences in shear moduli and Young's moduli obtained by the two methods are small but they are larger for bulk moduli of incompressible matrix and Poisson's ratios. The Young's moduli of high density foam plastics derived by the present model agree better with experimental ones.

关键词： effective moduli foam plastics three phase spheroidal model

Chemotherapy of multidrug-resistant human lung cancer combined with an MDR1 ribozyme retroviral vector in an orthotopic model

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Chinese Science Bulletin 1997年第3期42卷 231-234页

作者： Gao, ZQ Gao, zp Liu, XF Department of Pathology Beijing Medical University Beijing China

NON-SMALL-CELL lung cancer (NSCLC) accounts for 75%—80% of all lung cancers. Chemotherapy is the basic treatment for the patients with NSCLCs, which are often resistant to drugs because of tumor multidrug resistance, the main cause of lower cure rate. Overexpression of P-glycoprotein (Pgp), the product of multidrug resistance gene (MDR1), is the main mechamsm by which tumor produces multidrug resistance. MDR1 gene is known to induce multidrug resistance. MDR1 antisense RNA could inhibit the expression of MDR1 gene and reverse the multidrug resistance in multidrug-resistant human lung cancer. In clinical studies,

关键词： lung cancer orthotopic model MDR1 ribozyme reversal of drug resistance therapy.

Enthalpies of Formation of Binary Transition hcp Metal Based Alloys Calculated by Analytic Embedded Atom Method Model

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Journal of Materials Science & Technology 1999年第4期15卷 331-335页

作者： Zhang, BW Ouyang, YF Liao, SZ Jin, zp Chinese Acad Sci Int Ctr Mat Phys Shenyang 110015 Peoples R China Hunan Educ Inst Dept Phys Changsha 410012 Peoples R China Cent S Univ Technol Dept Mat Sci & Engn Changsha 410083 Peoples R China

A simple analytic modified embedded atom method (MEAM) including a modified term for hcp metals has been developed from the MEAM applied to the fee and bcc metals. The enthalpies of formation of all binary alloy systems for eight transition hcp metals are calculated with the MEAM. The calculations are in agreement with the experimental data available and results calculated from the Miedema theory. One can conclude that our MEAM is also effective to apply to the hcp metals and their alloys.

关键词： Transition metal alloys