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Evaluating changes in ecological land and effect of protecting important ecological spaces in China

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Journal of Geographical Sciences 2021年第9期31卷 1245-1260页

作者： GAO Jixi LIU Xiaoman WANG Chao WANG Yong FU zhuo HOU Peng LYU Na Ministry of Ecology and Environment Center for Satellite Application on Ecology and Environment Beijing 100094China State Key Laboratory of Resources and Environmental Information System Institute of Geographic Sciences and Natural Resources ResearchCASBeijing 100101China

It is important to quantitatively analyze the effects of protection of important ecological spaces in China to ensure national ecological *** considering changes in the ecological land,this study examines the effects of protecting three types of important natural ecological spaces in China from 1.80 to ***,considering important ecological spaces and their surroundings yields differences in the effects of protection between internal and external spaces,where this can provide a scientific basis for the categorization and zoning of China’s *** results show the following:(1.In 201.,the ratio of ecological land to important natural ecological spaces accounted for 92.64%.This land had a good ecological background that reflects the developmental orientation of important ecological spaces.(2)From 1.80 to 201.,the area of ecological land in important ecological spaces shrank but the rate of reduction was lower than the national average,which shows the positive effect of regulating construction in natural ecological *** restorative effects of ecological projects to convert farmland into forests and grasslands have been *** expanded ecological land is mainly distributed in areas where such projects have been implemented,and the reduced area is concentrated in grain-producing areas of the Northeast China Plain and agricultural oases of *** the future,the government should focus on strengthening the management and control of these areas.(3)The area ratio of ecological land was the highest in national nature *** rate of reduction in its area was the lowest and the trend of reduction was the smallest in national nature reserves,which reflects differences in the status of ecological protection among different spaces.(4)The ratio of ecological land to important ecological spaces was higher than that in the surrounding external space,and the rate of reduction in it was ***,the effects of internal and external protection

关键词： ecological spaces ecological land spatial and temporal dynamic changes protection effect categorized and zoned governance

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基于焊接温度场的焊缝跟踪与熔透控制

上海交通大学学报 2003年第12期37卷 1858-1861页

作者：项安潘俊民潘际銮上海交通大学电气工程系上海200030 清华大学机械工程系北京100084

研究了从焊接温度场中获取焊缝位置和熔透信息的方法,在此基础上设计了规则自调整模糊控制器,实现了MIG/MAG的焊缝跟踪与熔透控制.该系统已成功应用于螺旋管缝内焊自动跟踪与熔透控制.

关键词：焊接温度场焊缝跟踪熔透控制埋弧焊

The effect of decreasing alkalinity on microbial community dynamics in a sulfate-reducing bioreactor as analyzed by PCR-SSCP

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Science China(Life Sciences) 2006年第4期49卷 370-378页

作者： REN Nanqi1. ZHAO Yangguo1. WANG Aijie1. GAO Chongyang2, SHANG Huaixiang1. LIU Yiwei1.& WAN Chunli1.1. School of Environmental and Municipal Engineering, Harbin Institute of Technology, Harbin 1.0090, China 2. Key Laboratory of Forest Plant Ecology, Ministry of Education, Northeast Forestry University, Harbin 1.0040, China School of Environmental and Municipal Engineering Harbin Institute of Technology Harbin 150090 China Key Laboratory of Forest Plant Ecology Ministry of Education Northeast Forestry University Harbin 150040 China

PCR-single-strand conformation polymorphism (SSCP) and Southern blotting tech-niques were adopted to investigate microbial community dynamics in a sulfate-reducing bioreactor caused by decreasing influent alkalinity. Experimental results indicated that the sulfate-removal rate approached 87% in 25 d under the conditions of influent alkalinity of 4000 mg/L (as CaCO3) and sul-fate-loading rate of 4.8 g/(L·d), which indicated that the bioreactor started up successfully. The analy-sis of microbial community structure in this stage showed that Lactococcus sp., Anaerofilum sp. and Kluyvera sp. were dominant populations. It was found that when influent alkalinity reduced to 1.00 mg/L, sulfate-removal rate decreased rapidly to 35% in 3 d. Then influent alkalinity was increased to 3000 mg/L, the sulfate-removal rate rose to 55%. Under these conditions, the populations of Dysgo-nomonas sp., Sporobacte sp., Obesumbacterium sp. and Clostridium sp. got to rich, which predomi-nated in the community together with Lactococcus sp., Anaerofilum sp. and Kluyvera sp. However, when the alkalinity was decreased to 1.00 mg/L, the sulfate-removal rate rose to and kept stable at 70% and populations of Dysgonomonas sp., Sporobacter sp. and Obesumbacterium sp. died out, while some strains of Desulfovibrio sp. and Clostridium sp. increased in concentration. In order to determine the minimum alkalinity value that the system could tolerate, the influent alkalinity was de-creased from 1.00 to 400 mg/L secondly. This resulted in the sulfate-removal rate, pH value and ef-fluent alkalinity dropping quickly. The amount of Petrotoga sp., Prevotella sp., Kluyvera sp. and Neisseria sp. reduced obviously. The result data from Southern blotting indicated that the amount of sulfate-reducing bacteria (SRBs) decreased with influent alkalinity dropping. Analysis of the microbial community structure and diversity showed that the SRBs populations were very abundant in the in-oculated activated sludge and the al

关键词： alkalinity, community dynamics, PCR-single-strand conformation polymorphism (SSCP), Southern blotting, sulfate-reducing bacterium (SRB), fermentative acidogenic bacterium (FAB).

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填筑形成的码头岸坡稳定分析

天津大学学报（自然科学与工程技术版） 2003年第4期36卷 493-497页

作者：李飒闫澍旺杨进良孙万禾天津大学建筑工程学院岩土工程研究所天津300072 天津港湾工程研究所天津300022

利用极限平衡方法及有限元计算,求解深圳A港岸坡破坏的稳定分析及应力场和位移场,并探讨了填筑形成岸坡的破坏模式、破坏原因及稳定计算方法;发现由块石、碎石和砂填筑形成的岸坡的破坏面属于非圆弧滑动面,淤泥层的存在对岸坡的稳定有... 详细信息

利用极限平衡方法及有限元计算,求解深圳A港岸坡破坏的稳定分析及应力场和位移场,并探讨了填筑形成岸坡的破坏模式、破坏原因及稳定计算方法;发现由块石、碎石和砂填筑形成的岸坡的破坏面属于非圆弧滑动面,淤泥层的存在对岸坡的稳定有很大影响,其破坏模式和破坏原因等与其他形式的码头岸坡有显著的不同.

关键词：码头岸坡稳定极限平衡方法有限元法破坏模式破坏原因填筑应力场位移场

Molecular cloning and functional analysis of Chinese sturgeon (Acipenser sinensis) growth hormone receptor

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Science China(Life Sciences) 2009年第10期52卷 911-921页

作者： LIAO ZhiYong1. CHEN XiaoLi2 & WU MingJiang1.1.College of Life and Environmental Science, Wenzhou University, Wenzhou 325035, China 2 Capital Institute of Pediatrics, Beijing 1.0020, China College of Life and Environmental Science Wenzhou University Wenzhou China Capital Institute of Pediatrics Beijing China

A full length cDNA encoding the growth hormone receptor (GHR) of Chinese sturgeon was cloned in order to investigate the mechanism of growth hormone in regulating the growth of Chinese sturgeon. The open reading frame of the cloned Chinese sturgeon growth hormone receptor (csGHR) cDNA encodes a trans-membrane protein of 61. amino acids containing all the characteristic motifs of GHR. By sequence alignment, substitutions of amino acid residues highly conserved in other species were identified. Using the CHO cell culture system, the function of csGHR and the biological significance of the amino acid substitution in csGHR were examined. The promoter of serine protease inhibitor 2.1.(Spi2.1. was trans-activated upon stimulation of seabream GH (sbGH) in the csGHR-expressing CHO cells. Furthermore, CHO cells stably expressing csGHR were stimulated to proliferate by sbGH. In agreement with our previous report, Chinese sturgeon growth hormone-binding protein (csGHBP) was detected in the culture medium of CHO cells stably expressing csGHR. Mutation of Asp residue in the ligand binding motif in csGHR to Glu significantly enhanced csGHR's biological function, whereas mutation of Asp residue to Ala decreased its biological function. The results demonstrated that the cloned csGHR was of full biological function and the csGHBP could be generated through proteolysis of csGHR. These findings might provide new insights into thoroughly understanding the regulatory mechanism of Chinese sturgeon growth.

关键词： Chinese sturgeon GHR GHBP mutation cDNA cloning

Processing for Zero-Failure Data of the Products

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Journal of Systems Engineering and Electronics 2002年第3期13卷 91-97页

作者： Han Ming 1.2 & Cui Yuping 3 (1. Department of Statistics, Renmin University of China, Beijing 1.0872, P.R. China 2. Department of Mathematics, Zhejiang Ocean University, Zhoushan 31.004, P.R. China 3. Department of Machine and Electron, Dongbei Power College, Jilin 1.001., P.R. China) Department of Statistics Renmin University of China Beijing 100872 P. R. China Department of Mathematics Zhejiang Ocean University Zhoushan 316004 P. R. China Department of Machine and Electron Dongbei Power College Jilin 130012 P. R. China

In this paper, an estimation method for reliability parameter in the case of zero-failuare data-synthetic estimation method is given. For zero-failure data of double-parameter exponential distribution, a hierarchical Bayesian estimation of the failure probability is presented. After failure information is introduced, hierarchical Bayesian estimation and synthetic estimation of the failure probability, as well as synthetic estimation of reliability are given. Calculation and analysis are performed regarding practical problems in case that life distribution of an engine obeys double-parameter exponential distribution.

关键词： Reliability Zero-failure data Failure probability Hierarchical Bayesian estimation Synthetic estimation.

中国学术期刊影响因子年报(自然科学与工程技术2023版)

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护理学报 2024年第12期 2-2页

作者： 1.《中国学术期刊(光盘版)》电子杂志社有限公司 2.中国科学文献计量评价研究中心《中国学术期刊(光盘版)》电子杂志社有限公司中国科学文献计量评价研究中心

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Effect of the P1.Medium and the ECM Medium on Embryo Quality in IVF

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Journal of Reproduction and Contraception 2009年第2期20卷 67-72页

作者： Qian CHEN Ai-jun ZHANG Yun FENG Xiao-wei LU Dong-mei JI Zhi-peng XU Center of Reproductive Medicine Ruijing Hospital Medical School of Shanghai Jiaotong University Shanghai200025 China Center of Reproductive Medicine Drum Tower Hospital Medical School of Nanjin University Nanjin 210008 China

Objective To investigate the effect of the glucose-free preimplantation stage one （P1. medium and the ECM medium on embryo development quality in IVF. Methods The patients with ≥4 zygotes of 2PN were studied. A total of 201.retrieval cycles were included in a prospective randomized study. Each patient was herself control. Half of zygotes of 2PN were transferred into ECM medium （group A） and half into P1.medium （group B）for further culture. Embryo development was evaluated on the day of embryo transfer. The efficacy of ECM was compared with P1.as culture medium for the development of preimplantation embryos. Results No statistically significant differences were noted between the two groups regarding embryo-cleavage rate （97.1.% vs 97.55%） and rate of normal-cleaving embryos （58.29% and 58.37%）. The rate of top-quality embryos was statistically higher in group A than in group B （27.59% vs 1..75%, P〈O.05）. Embryo quality, as assessed by morphological parameters （the amount of detached anuclear fragments 〉30%）, was better in group A than in group B （1..86% vs 21.75%）, however, there was no statistically significance. Both the rate of good-quality embryos （47.95% vs 46.1.%） and available embryos （63.22% vs 61.1.%） were higher in group A than in group B, but there was also no statistically significance. Conclusion The ECM medium may be associated with a better embryo quality compared with the P1.medium.

关键词： culture media IVF preimplantation embryo development

中国近海浮游介形类大尺度生态研究Ⅳ.浮游介形类的生态群落与群落特征

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海洋学报 1998年第3期20卷 98-103页

作者：林景宏陈瑞祥郭凤飞国家海洋局第三海洋研究所

以中国近海的浮游介形类为研究对象，分析其群落结构，将之区分为近岸群落，陆架缘区群落、外海群落以及介于其间的不稳定的、有时是孤立的过渡群落，同时，还阐述各群落的主要特征及讨论各群落的特权种结构。此外，根据海上取样结果，... 详细信息

以中国近海的浮游介形类为研究对象，分析其群落结构，将之区分为近岸群落，陆架缘区群落、外海群落以及介于其间的不稳定的、有时是孤立的过渡群落，同时，还阐述各群落的主要特征及讨论各群落的特权种结构。此外，根据海上取样结果，本文仅讨论０～２００ｍ水域内的群落结构。

关键词：介形类群落结构群落特征特征种生态尺度