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岷江上游亚高山典型森林植被群落数量特征研究

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四川林业科技 2004年第3期25卷 17-21页

作者：陈秀明李荣伟王乐辉宿以明何飞蔡小虎孙鹏四川省林业科学研究院四川成都610081

本文应用Shannon Wiener多样性指数 ,Simpson生态优势度指标以及群落均匀度指标 ,定量研究岷江上游亚高山主要森林群落的组成结构特征。以原始林的数量特征为参照 ,比较分析了岷江上游亚高山植被自然恢复与人工恢复的群落数量特征。结... 详细信息

本文应用Shannon Wiener多样性指数 ,Simpson生态优势度指标以及群落均匀度指标 ,定量研究岷江上游亚高山主要森林群落的组成结构特征。以原始林的数量特征为参照 ,比较分析了岷江上游亚高山植被自然恢复与人工恢复的群落数量特征。结果表明 ,岷江上游亚高山主要森林群落的物种多样性指数为 0 5 5～4 6 2 ,多数在 1～ 3之间 ,多样性指数值偏低。生态优势度为 0 0 6～ 0 92 ,多数在 0 4 0～ 0 80之间。群落均匀度为 0 2 7～ 1 39之间。原始林的群落组成及结构特征取决于人为干扰程度。在森林植被恢复过程中 ,人工营造的混交林的群落结构优于自然恢复的次生林的群落结构 ,因而具有较好的生态效应 ,而人工营造的纯林的群落结构则比自然恢复的次生林差。

关键词：岷江上游亚高山森林物种多样性生态优势度群落均匀度

Transformation Behavior of Low Carbon Steels Containing Two Different Si Contents

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Journal of Iron and Steel Research International 2009年第2期16卷 55-60页

作者： CAI ming-hui DING Hua ZHANG Jian-su li Long li Xiao-bin DU lin-xiu College of Materials and Metallurgy Northeastern University Shenyang 110004 Liaoning China State Key Laboratory of Rolling Automation Northeastern University Shenyang 110004 Liaoning China Technology Center Baoshan Iron and Steel Group Co Shanghai 201900 China National Institute for Materials Science Tsukuba 305-0047 Japan

Continuous cooling transformation behaviors of low carbon steels with two Si contents （0. 50% and 1. 35%） were investigated under undeformed and deformed conditions. Effects of Si contents, deformation, and cooling rates on γ transformation start temperature （Ar3）, phase microstructures, and hardness were studied. The results show that, in the ease of the deformation with the true strain of 0. 4, the length of bainitic ferrite laths is significantly decreased in low Si steel, whereas, the M/A constituent becomes more uniform in high Si steel. An increase in cooling rates lowers the Ar3 greatly. The steel with higher level of Si exhibits higher Ar3, and higher hardness both under undeformed and deformed conditions compared with the steel with a lower Si content. Especially, the influence of Si on At3 is dependent on deformation. Such effects are more significant under the undeformed condition. The hardness of both steels increases with the increase of cooling rates, whereas, the deformation involved in both steels reduces the hardness.

关键词： Si content low carbon steel cooling rate transformation behavior bainitic morphology

Two new phenolic compounds from Artemisia sphaerocephala

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Chinese Chemical Letters 2007年第5期18卷 551-553页

作者： Dong Bao Zhao lin Xi li xiu Hua liu ming Jing li Wen ling Wang College of Chemistry and Chemical Engineering Henan University Kaifeng 475001 China Institute of Natural Products ＆ Medicine Chemistry Henan University Kaifeng 475001 China Xuchang General Cigarette Factory Xuchang 461000 China

Two new phenolic compounds were isolated from whole plant ofArtemisia sphaerocephala. The structures were elucidated on the basis of spectroscopic methods as 4-（1-hydroxylethyl）-phenol-l-O-β-D-glucopyranoside and 4... 详细信息

关键词： Artemisia sphaerocephala Phenolic Spectroscopic methods

Some questions about landscape modelling

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Journal of Environmental Sciences 2001年第4期13卷 459-465页

作者： Michel Godron li xiu-zhen CCAS F18410BrinonFrance Institute of Applied Ecology Chinese Academy of SciencesShenyang 110016China

The paper discusses mainly about the modelling process and related problems with examples from Chinese and French cases. Five practical problems must be solved for modelling the functioning of any landscape: ( 1) The field data are necessarily taken with a sampling procedure that implies a spatial (and often temporal) scale. (2) Every landscape modelled has to be identified, delimited and characterised before application of the hierarchical theory. (3) The functioning of a landscape involves data of multiple types (climate, soil, vegetation, fauna, buildings, communications, economy, aesthetics, etc.) which must be integrated in a holistic approach. (4) Every landscape is spatially heterogeneous, and the structure of the model must be more or less isomorphic with its heterogeneity. ( 5) The evolution of the landscape must be modelled on a rather long period of time. For all these reasons, it is necessary to build ad hoc models. Object-oriented computing languages may be useful for this purpose.

关键词： landscape modelling scale hierarchy holistic approach application

Decipher hydrocarbon generation and accumulation based on fluid inclusion and chronology:A case study from the Upper Paleozoic buried-hills in Huanghua Depression,Bohai Bay Basin

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Petroleum Science 2023年第4期20卷 1998-2008页

作者： li-Hong Zhou Yong li Feng-ming Jin Jin-Feng Xie xiu-Gang Pu li-Xin Fu Da Lou Yang Tian PetroChina Dagang Oilfield Company Tianjin300280China State Key Laboratory of Coal Resources and Safe Mining and College of Geosciences and Surveying Engineering China University of Mining and TechnologyBeijing100083China

Deciphering hydrocarbon generation and accumulation stage is of significance to understand oil and gas evolution and seek exploration *** the Upper Paleozoic buried-hills in the Huanghua Depression,Bohai Bay Basin,as a case study,hydrocarbon generation environment and detailed accumulation process are revealed by fluid inclusions observations,Laser Raman spectroscopy,Fourier Infrared spectroscopy,and K-Ar isotope *** results show that both oil and gas inclusion were captured in the quartz overgrowth,dissolved feldspar and calcite microfractures,showing blue to dark brown *** grains containing oil inclusions index(GOI)of oil,oil&gas and gas being 25%,65%,and 10%and the inclusions with abundant methyl groups and short chains,both indicate high thermal *** series of fluids inclusion is generally observed,evidenced by the concentrated homogenization temperature of 135-145℃ and salinity of 3%-15 w.t.%NaCl equiv,indicating one primary charging *** gas and gas&liquid inclusions mainly contain CH_(4),with also peaks indicating CO_(2) and N_(2.)The Carboniferous and Permian biomarkers show reducing environment with brackish water,with organic matter sources both from marine and *** relative content ofααα20RC_(27),ααα20RC_(28),andααα20RC_(29) exhibit source contributions both from algae and higher plants,and mainly of II2 to III *** coal derived gas and oil associated hydrocarbons are identified from most of the *** the fluid homogenization temperature and salinity,as well as the thermal evolution history,the hydrocarbon generated from the Upper Paleozoic was concentrated at the end of the Eocene(40 Ma±),while the beginning of charging is 60 Ma±.The Wumaying Buried-hill is of only coal derived gas and has potential for inner coal measure natural gas *** results provide a detailed understanding of hydrocarbon accumulations in the study area,which can also be reference for impro

关键词： Petroleum accumulation Buried hills K–Ar isotope Fluid inclusions Huanghua depression Bohai Bay Basin

Avoiding sealing failure of flanged connection for tubes made of dissimilar materials subjected to elevated temperature

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Nuclear Science and Techniques 2019年第1期30卷 107-112页

作者： Qi-ming li Chong Zhou Jian Tian Yao Fu Yang Zou Na-xiu Wang Shanghai Institute of Applied Physics Chinese Academy of Sciences

Carbonic composite materials and ceramics appear to be excellent structural materials for parts subjected to very high temperatures in molten salt reactors(MSRs), in which the reactor core outlet temperature is normally above 700℃. Because of the high temperature,there are major challenges in the sealing of flanged connections for tubes made of alloys and nonmetallic materials. In this study, an improved method for sealing bolted flange connections for tubes made of dissimilar materials at high temperature is analyzed. The study focuses on the compensation mechanism for the difference in thermal expansion between the bolts and the flanges. An angle is introduced for the sealing surface in the flanged connection to provide effective sealing. The arctangent of the angle is the ratio of the thickness between the theoretical core of the sealing surface and the outside end face of the flange to the distances between the axis of the flanged joint and the theoretical core of the sealing surface of the flange; the sealing surface of the flange, which is made of the same material as the fastening assemblies, faces the fastening assemblies. To ensure effective sealing, the frictional coefficient between the two sealing surfaces should not exceed the tangent of the angle. This result does not agree well with the solution given by previous researchers. Further, in the modified flanged connection, the compression of each bolt in the clamped condition is increased to maintain the compaction force unchanged without increasing the number of bolts on the flanged joint.

关键词： Sealing Composite flanged connections Thermal expansion Mechanical analysis Molten salt reactors

Enhancing low-temperature NO_x storage and reduction performance of a Pt-based lean NO_x trap catalyst

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Rare Metals 2019年第1期38卷 81-86页

作者： Tong Wang li-Wei Jia xiu-Ting Wang Gang Wang Fu-Qiang Luo Jia-ming Wang School of Automotive and Traffic Engineering Jiangsu University Wuxi Weifu Environmental Catalysts Co. Ltd

Two lean NO_x trap(LNT) catalysts, Pt/BaO/CeO_2 + Al_2O_3 and Pt/BaO/CeO_2-Al_2O_3, were prepared and compared for low-temperature(< 250℃) NO_x storage and reduction performance. The influence of the form of ceria on... 详细信息

Two lean NO_x trap(LNT) catalysts, Pt/BaO/CeO_2 + Al_2O_3 and Pt/BaO/CeO_2-Al_2O_3, were prepared and compared for low-temperature(ling, product selectivity and thermal *** coupled plasma-atomic emission spectrometry(ICP-AES), Brunner-Emmet-T eller(BET), H_2-pulse chemisorption and X-ray diffraction(XRD) were conducted to characterize the physical properties of LNT catalysts. NO_x storage capacity and NO_x conversion efficiency were measured to evaluate NO_x storage and reduction performance of LNT catalysts. Pt/BaO/CeO_2-Al_2O_3 catalyst exhibits higher NO_x storage capacity than Pt/BaO/CeO_2 + Al_2O_3 catalyst in the temperature range of 150-250 ℃. Meanwhile, Pt/BaO/CeO_2-Al_2O_3 catalyst shows better NO_x conversion efficiency and N_2 selectivity. XRD results indicate that the thermal stability of CeO_2-Al_2O_3 complex oxide is superior to that of pure CeO_2. H_2-pulse chemisorption results show that Pt/BaO/CeO_2-Al_2O_3 catalyst has higher Pt dispersion than Pt/BaO/CeO_2 + Al_2O_3 catalyst over fresh and aged samples. The improved physical properties of Pt/BaO/CeO_2-Al_2O_3 catalyst are attributed to enhance the NOx storage and reduction performance over Pt/BaO/CeO_2 + Al_2O_3 catalyst.

关键词： NOx storage and reduction Low temperature Ceria Ceria-alumina LNT

A New Approach to Ethyl 1-Aroyl/Aroylmethyl-5-methyl-3- methylthiopyrazole-4-carboxylates: High Regioselectivity in Alkylation and Acylation Reactions between N-1 and N-2 of a Pyrazole Derivative

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Chinese Chemical Letters 2005年第9期16卷 1161-1164页

作者： li Rong WEN Gui Long ZHAO ming li Wen Ying QI xiu li ZHANG Hua Zheng YANG College of Chemistry and Molecular Engineering Qingdao University of Science and Technology Qingdao 266042 State Key Laboratory of Elemento-organic Chemistry Institute of Elemento-Organic Chemistry Nankai University Tianjin 300071 Ocean Food and Drug Institute Ocean University of China Qingdao 266003

Two series, totalizing twelve, of new compounds, ethyl 1-aroyl/aroylmethyl-5-methyl-3- methylthiopyrazole-4-carboxylates 5/6, have been synthesized via highly regioselective acylation and alkylation of ethyl 3-methyl-5-methylthio-1H- pyrazole-4-carboxylate 2a with aroyl chloride 3 and alpha-tosyloxysubstitutedacetophenones 4. Unexpected structures of the product have been unambiguously determined by both X-ray crystallographic analysis and 2D NMR.

关键词： Pyrazole regioselectivity X-ray crystallographic analysis 2D NMR

Structure and Adsorption Properties to TVOC of Orange Peel Modified with KOH

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Chinese Journal of Structural Chemistry 2020年第5期39卷 873-883页

作者： CHEN li YAN Rui XU Wen-xiu XIONG Xiao-ming Chemistry and Chemical Engineering Xingtai UniversityXingtai 054001China

Food waste orange peel was employed as a raw material to prepare biomass adsorbent to solve the indoor Total Volatile Organic Compounds(TVOC).The preparation process of orange peel treated with KOH was optimized by the quadratic regression orthogonal rotation,and the regression model and optimal processing conditions were *** structure of the adsorbent was characterized by BET,SEM,TEM,EDS,XRD and FTIR *** adsorption properties and desorption regeneration were *** results showed the maximal removal rate Ymax was 9.4824%when KOH concentration was 0.3 mol/L,the soaking time of KOH was 26 h and that of HCl was 2.89 *** best single factor condition was the adsorbent with 40 mesh size and 6.0 *** adsorption of modified orange peel on TVOC conformed to the Freundlich models,which was more inclined to multi-layer active site *** adsorption law followed the quasi-second-order kinetic model(R^2=0.955),indicating the adsorption was a physico-chemical mixture but controlled by physical adsorption and it was a spontaneous endothermic *** modified orange peel exposed more sites and had stronger chemical groups,which were beneficial to *** adsorbent has a significantly better TVOC removal rate than other materials at 1%level,that is,modified orange peel>diatomite>activated carbon>bamboo charcoal>macroporous *** addition,it had good recycling and regeneration capacity.

关键词： orange peel KOH modification TVOC adsorption structure