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世界建筑导报 2006年第8期21卷 70-71页

作者： M.Robain R.Tisnado JF.Bonne A.Bretagnolle RH.Arnaud lm.fischer M.Lehmann R.Ayache 法国AS.建筑工作室

Subtropical urban turfs： Carbon and nitrogen pools and the role of enzyme activity

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Journal of Environmental Sciences 2018年第3期30卷 18-28页

作者： Ling Kong lm Chu School of Life Sciences The Chinese University of Hong Kong Shatin NT Hong Kong SAR China department of orthopaedics & traumatology faculty of medicine the chinese university of hong kong

Urban grasslands not only provide a recreational venue for urban residents, but also sequester organic carbon in vegetation and soils through photosynthesis, and release carbon dioxide through respiration, which largely contribute to carbon storage and fluxes at regional and global scales. We investigated organic carbon and nitrogen pools in subtropical turfs and found that dissolved organic carbon（DOC） and dissolved organic nitrogen（DON）were regulated by several factors including microbial activity which is indicated by soil enzymatic activity. We observed a vertical variation and different temporal patterns in both soil DOC, DON and enzyme activities, which decreased significantly with increasing soil depths. We further found that concentration of soil DON was linked with turf age. There were correlations between grass biomass and soil properties, and soil enzyme activities. In particular, soil bulk density was significantly correlated with soil moisture and soil organic carbon（SOC）. In addition, DOC correlated significantly with DON. Significant negative correlations were also observed between soil total dissolved nitrogen（TDN） and grass biomass of Axonopus compressus and Zoysia matrella. Specifically, grass biomass was significantly correlated with the soil activity of urease and β-glucosidase. Soil NO3-N concentration also showed negative correlations with the activity of both β-glucosidase and protease but there were no significant correlations between cellulase and soil properties or grass biomass. Our study demonstrated a relationship between soil C and N dynamics and soil enzymes that could be modulated to enhance SOC pools through management and maintenance practices.

关键词： Dissolved organic carbon (DOC)lDissolved organic nitrogen (DON)lSoil enzymelTurfgrass

Comparison study of several numerical integration schemes used in calculations of density functional theory

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Chinese Journal of Chemistry 1996年第4期14卷 289-296页

作者： Hong, GY Li, lm BEIJING UNIV COLL CHEM & MOL ENGNSTATE KEY LAB RARE EARTH MAT CHEM & APPLICATBEIJING 100871PEOPLES R CHINA

Several numerical integration schemes for the evaluation of matrix elements in density functional theory calculations have been studied and compared by computational practice. The best scheme was found to be the combination of the atomic partition function proposed by Becke with the scaled generalized Gauss-Laguerre quadrature formula for radial integration suggested by Yang, which achieve the highest convergence rate to the numerical integration. With the same number of integration points, the accuracy of the calculated results by this scheme is higher by 1 to 2 orders of magnitudes than that by other schemes. The reason for achieving higher accuracy by this scheme has been proposed preliminarily.

关键词： density functional theory partition function numerical integration Gaussian quadrature numerical error

Is acute dyspnea related to oxaliplatin administration?

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World Journal of Gastroenterology 2006年第36期12卷 5907-5908页

作者： lm Pasetto S Monfardini Istituto Oncologico Veneto Medical Oncology V. Gattamelata 64 Padua 35128 Italy

The standard adjuvant treatment of colon cancer is fluorouracil plus leucovorin. Oxaliplatin improves the efficacy of this combination in patients with stage 111 colon cancer and moreover its toxicity is well tolerable. We describe a rare clinical case of acute dyspnoea probably related to oxaliplatin at one month from the end of the adjuvant treatment. A 74-year-old man developed a locally advanced sigmoid carcinoma （pT3N1M0）. A port a cath attached to an open-ended catheter was implanted in order to administer primary chemotherapy safely according to the FOLFOX4 schedule. One month following the end of the 6^th cycle, the patient referred a persistent cough and moderate dyspnoea. Chest radiography displayed a change in the lung interstitium, chest CT scan confirmed this aspect of adult respiratory distress syndrome, spirometry reported a decreased carbon monoxide diffusion capacity. Antibiotic and corticosteroids were administered for 10 d, then a repeated chest X ray evidenced a progressive pulmonary infiltration. A transbronehial biopsy and cytology did not show an infective process, a CT scan reported radiological abnormalities including linear and nodular densities which were becoming confluents. Antimicotic and antiviral drugs did not evidence any benefit. The antiviral therapy was stopped and high dose metilprednisolone was started. The patient died of pulmonary distress after 10 d.

关键词： Acute dyspnea Oxaliplatin Colon cancer

X-RAY POWDER DIFFRACTION DATA AND STRUCTURE REFINEMENT OF COMPOUND ErNi_2Si_2

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中国有色金属学会会刊：英文版 1998年第4期8卷 91-94页

作者： Yan, JL Ou, XL Zeng, lm Guangxi Univ Inst Mat Sci Nanning 530004 Peoples R China Tianjin Elect Mat Res Inst Tianjin 300192 Peoples R China

１ＩＮＴＲＯＤＵＣＴＩＯＮＴｈｅｒａｒｅｅａｒｔｈｃｏｍｐｏｕｎｄｓＲＥＴ２Ｓｉ２，ｗｈｅｒｅＲＥｉｓａｒａｒｅｅａｒｔｈｅｌｅｍｅｎｔａｎｄＴｉｓａｔｒａｎｓｉｔｉｏｎｍｅｔａｌｅｌｅｍｅｎｔ，ｈａｖｅｂｅｅｎｓｔ... 详细信息

１ＩＮＴＲＯＤＵＣＴＩＯＮＴｈｅｒａｒｅｅａｒｔｈｃｏｍｐｏｕｎｄｓＲＥＴ２Ｓｉ２，ｗｈｅｒｅＲＥｉｓａｒａｒｅｅａｒｔｈｅｌｅｍｅｎｔａｎｄＴｉｓａｔｒａｎｓｉｔｉｏｎｍｅｔａｌｅｌｅｍｅｎｔ，ｈａｖｅｂｅｅｎｓｔｕｄｉｅｄｗｉｔｈｇｒｅａｔｉｎ?..

关键词： ErNi 2Si 2 X ray powder diffraction Rietveld structure refinement

Time-Dependent Reliability Analysis of Offshore Structures

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China Ocean Engineering 1997年第2期12卷 151-160页

作者： Tang, lm Xi, X Department of Naval Architecture and Ocean Engineering Shanghai Jiaotong University Shanghai 200030 China

During the life of an offshore structure, its structural strength declines due to various kinds of damages related to the time factor. In this paper, four major kinds of damages, including damages caused by fatigue, dent, corrosion and marine life, are discussed. Based on these analyses, formulas for the evaluation of the damaged structure reliability are derived. Furthermore the computer program ISM for the analysis of structural reliability is developed by the use of Advanced First Order Second Moment method and Monte-Carlo Importance Sampling method. The reliability of a turbular joint and a beam are studied as numerical examples. The results show that the theory and the analysis method given in this paper are reasonable and effective.

关键词： structural reliability analysis fatigue damage dent damage corrosion damage Monte-Carlo importance sampling method

DIFFUSION WELDING FOR 6061 Al REINFORCED WITH SiCw WHISKER

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Journal of Wuhan University of Technology(Materials Science) 1999年第1期14卷 1-5页

作者： Niu, JT Liu, lm Han, LH Harbin Inst Technol Sch Mat Sci & Engn Harbin 150001 Peoples R China

The weldability of SiCw/6061Al -was investigated. From the results of experiments, it is found that the strength of joint is mainly influenced by welding temperature, and high strength of joint is obtained under melding temperature between liquidus and solidus of matrix alloy. Diffusion welding of SiCw/6061Al was successfully realized with appropriate ivelding parameters.

关键词： SiCw/6061Al composite diffusion welding welding temperature

1,3-Dipolar Cycloaddition Reaction between Vinyl Acetate and N-Alkyl Hydroxypyridinium Halide

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Chinese Chemical Letters 2001年第12期12卷 1053-1054页

作者： Zhou, SF Su, JY Zeng, lm Zhongshan Univ Sch Chem & Engn Guangzhou 510275 Peoples R China

1, 3 Dipolar cycloaddition reaction between vinyl acetate and 3-hydroxypyridiniun betaine was performed under solid-liquid phase transfer catalytic condition, This reaction has been successfully used on the synthesis ... 详细信息

关键词： 1,3-dipolar cycloaddition 3-hydroxypyridiniun betaines dipolarphiles

Densification of the Tungsten Heavy Alloys at 1473 K and Fabrication of W-Mo System FGM with Density Gradient

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Journal of Materials Science & Technology 1999年第3期15卷 229-232页

作者： Xiong, HP Zhang, lm Li, JG Yuan, RZ Wuhan Univ Technol State Key Lab Adv Technol Mat Synthesis & Proc Wuhan 430070 Peoples R China

The tungsten heavy alloys with Hi-Al and Fe-Al additives were sintered by hot-press method at 1473 K for 1 h. It was found that the relative density of the W-Fe alloy could be increased evidently by addition of Al. However, the relative density of W-Ni-Al alloy with low content of Al was conversely decreased considerably compared with that of W-Ni alloy. The causes have been studied. The sintering experiments of Mo alloy and W-Mo alloys with 3 wt pet Fe-1.5 wt pet Al additives were also carried out under the same sintering condition of low temperature. Finally, W-Mo system FGM with density gradient was successfully fabricated. Its density changed gradually from 17.0x10(3) kg/m(3) to 9.5x10(3) kg/m(3) within the middle 1.1 mm thickness range.

关键词： Tungsten alloys

EFFECTS OF MICROSTRUCTURE ON THE MACROSCOPIC ELASTO-PLASTIC PROPERTIES OF METAL MATRIX COMPOSITES

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Acta Mechanica Solida Sinica 1996年第1期9卷 52-58页

作者： Chen, HR Su, XF Tang, lm DALIAN UNIV TECHNOL RES INST ENGN MECHDALIAN 116023PEOPLES R CHINA

The generalized self-consistent finite-element iterative averaging method was adopted to analyze the elasto-plastic tensile properties of SiC whiskers reinforced aluminum matrix composites. The effects of varying fiber's aspect ratio and volume fraction on the macroscopic elasto-plastic deformation of the composites were studied. By the analysis of microscopic stress fields, the relation between the propagation of the elasto-plastic region in the matrix and the macroscopic elasto-plastic deformation of composites was discussed. It was found that the propagation of the plastic region in the matrix between the fiber's ends would affect prominently the elasto-plastic tensile behaviour of the composites. It was shown that the characterization of the stress-strain response in terms of the 0.2% offset yield strength is incomplete.

关键词： metal-matrix composites microstructure macroscopic elasto-plastic behaviour microscopic plastic region generalized self-consistent finite-element iterative averaging method