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《定量分析》教学方法探讨与研究
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作者 康绍森 《中国农业教育》 2002年第3期32-32,共1页
关键词 《定量分析》 教学方法 教学研究 分析化学 实验教学
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A GIS-based Study on Suitability Estimation of Tea Cultivation in Qimen County 被引量:11
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作者 叶寅 何方 +3 位作者 张学英 宫志锋 吕莎莎 方亮 《Agricultural Science & Technology》 CAS 2011年第1期149-152,共4页
On the basis of data from Soil Test and Formula Fertilization project in Qimen county,we employed Geographic Information System Software ArcGIS 9.2 and CLRMIS(Cultivated Land Resource Management Information System at... On the basis of data from Soil Test and Formula Fertilization project in Qimen county,we employed Geographic Information System Software ArcGIS 9.2 and CLRMIS(Cultivated Land Resource Management Information System at County Scale) to establish region-specific estimation index system for tea cultivation in Qimen County by determining the estimation units,and carried out quantitative estimation analysis on tea cultivation there via comprehensive evaluation indices for natural elements of cultivated land.The results showed that the highly suitable,suitable,reluctantly suitable and unsuitable acreages are 5 665.8,8 327.1,8 415.9 and 11 979.9 hm2 respectively,accounting for 24.0%,35.3%,35.7% and 5.1% of the total acreage of cultivated land.These results would facilitate the production of high yield and quality tea in Qimen County. 展开更多
关键词 Tea planting suitability Cultivated land GIS Quantitative assessment
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Qualitative and Quantitative Analysis of Rhizoma of Polygonum cuspidatum 被引量:4
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作者 张勉 王磊 +2 位作者 黄澜 张紫佳 王峥涛 《Journal of Chinese Pharmaceutical Sciences》 CAS 2004年第2期106-111,共6页
Aim To establish reliable methods for evaluating the quality of rhizoma of Polygonum cuspidatum( Huzhang in Chinese). Methods TLC and HPLC were employed for the chemical identification and content determination,respec... Aim To establish reliable methods for evaluating the quality of rhizoma of Polygonum cuspidatum( Huzhang in Chinese). Methods TLC and HPLC were employed for the chemical identification and content determination,respectively. Results A qualitative TLC method and a quantitative HPLC method with piceid as the reference substance were established, respectively. With piceid as the reference substance and ethyl acetate-methanol-formic acid-water ( 19:3:0.5:1) as the mobile phase, a TLC method for the identification of Huzhang from the commonly used crude drugs of the same family was also set up. Conclusion The established TLC method can reasonably appraise the quality of the drug and easily distinguish Huzhang from the other commonly used crude drugs of the same family. The HPLC method for determining piceid is simple, reproducible, accurate, and feasible. 展开更多
关键词 TLC HPLC PICEID EMODIN rhizoma of Polygonum cuspidatum
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Determination of Melamine by Infrared Spectroscopy Based on Nonlinear Modeling 被引量:1
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作者 张恒 高曼侠 +2 位作者 许兆棠 李文谦 王琪 《Agricultural Science & Technology》 CAS 2010年第8期133-136,共4页
[Objective] The aim was to develop a nonlinear model of quantitative analysis of melamine content by infrared spectroscopy and provide theoretical basis for the nondestructive detection of melamine. [Method] According... [Objective] The aim was to develop a nonlinear model of quantitative analysis of melamine content by infrared spectroscopy and provide theoretical basis for the nondestructive detection of melamine. [Method] According to dynamics,mathematical modeling and optimization theory,linear and nonlinear models were respectively set up by taking an absorption peak of 1 550 cm-1 as characteristic absorption peak. [Result] The correlation coefficient of nonlinear model was 0.922 7 and the recovery was 96%,which showed that the nonlinear model was more accurate than linearity model with correlation coefficient of 0.904 9 and recovery of 557%. [Conclusion] It is feasible to determine melamine content by using the nonlinear model quantitatively. 展开更多
关键词 Infrared spectroscopy Quantitative analysis Nonlinear model MELAMINE
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Predicting pillar stability for underground mine using Fisher discriminant analysis and SVM methods 被引量:16
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作者 周健 李夕兵 +2 位作者 史秀志 魏威 吴帮标 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2011年第12期2734-2743,共10页
The purpose of this study is to apply some statistical and soft computing methods such as Fisher discriminant analysis (FDA) and support vector machines (SVMs) methodology to the determination of pillar stability ... The purpose of this study is to apply some statistical and soft computing methods such as Fisher discriminant analysis (FDA) and support vector machines (SVMs) methodology to the determination of pillar stability for underground mines selected from various coal and stone mines by using some index and mechanical properties, including the width, the height, the ratio of the pillar width to its height, the uniaxial compressive strength of the rock and pillar stress. The study includes four main stages: sampling, testing, modeling and assessment of the model performances. During the modeling stage, two pillar stability prediction models were investigated with FDA and SVMs methodology based on the statistical learning theory. After using 40 sets of measured data in various mines in the world for training and testing, the model was applied to other 6 data for validating the trained proposed models. The prediction results of SVMs were compared with those of FDA as well as the measured field values. The general performance of models developed in this study is close; however, the SVMs exhibit the best performance considering the performance index with the correct classification rate Prs by re-substitution method and Pcv by cross validation method. The results show that the SVMs approach has the potential to be a reliable and practical tool for determination of pillar stability for underground mines. 展开更多
关键词 underground mine pillar stability Fisher discriminant analysis (FDA) support vector machines (SVMs) PREDICTION
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混合弱酸分步滴定的最低离解常数比
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作者 王妍妍 《辽宁教育行政学院学报》 北大核心 1996年第5期69-70,共2页
混合弱酸分步滴定的最低离解常数比王妍妍1引言在多数分析化学教材中,关于混合弱酸分步满定的条件只是概括地指出其离解常数比应大于或等于105[1][2],也有的认为应大于或不小于104[3],但都未给出理论上的推导或证明... 混合弱酸分步滴定的最低离解常数比王妍妍1引言在多数分析化学教材中,关于混合弱酸分步满定的条件只是概括地指出其离解常数比应大于或等于105[1][2],也有的认为应大于或不小于104[3],但都未给出理论上的推导或证明.文献[4]证明了多元的分步滴定的... 展开更多
关键词 离解常数 分步滴定 混合弱酸 分析化学》 计量点 《定量分析》 东北师范大学出版社 定量化学分析 复旦大学出版社 分析浓度
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The quantified analysis of China's GM cotton yield capacity by C-D function and stochastic frontier model
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作者 张涛 薛宝娣 《Hunan Agricultural Science & Technology Newsletter》 2004年第1期11-13,共3页
Using a modified C D function and stochastic frontier model, the paper analyzed China's cotton yield capacity and found that the yield and technical efficiency of China's cotton planting system can be increas... Using a modified C D function and stochastic frontier model, the paper analyzed China's cotton yield capacity and found that the yield and technical efficiency of China's cotton planting system can be increased by the use of genetically modified (GM) varieties. 展开更多
关键词 GM cotton yield capacity C D function stochastic frontier model
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Wrinkling prediction in rubber forming of Ti-15-3 alloy 被引量:4
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作者 孙永娜 万敏 吴向东 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2013年第10期3002-3010,共9页
Wrinkling is a common failure in the sheet metal forming of titanium owing to the relatively poor ability to shrink. It is important to predict wrinkling accurately in the sheet metal forming without costly trials. Th... Wrinkling is a common failure in the sheet metal forming of titanium owing to the relatively poor ability to shrink. It is important to predict wrinkling accurately in the sheet metal forming without costly trials. The ABAQUS/Explicit code was utilized to predict the wrinkling behavior in the sheet metal forming of Ti-15-3 alloy sheets. In terms of the comparison of wrinkling behavior between the simulation and experiment of the Fukui's conical cup tests at room temperature, the sensitivities of wrinkling simulation to various input parameters were evaluated comprehensively and quantitatively. Prediction of wrinkling and influence of rubber hardness on the winkling behavior in the rubber forming of convex flange were investigated quantitatively and validated by the rubber forming experiments. The excellent agreements between the simulations and the experiments conIirmed the accuracy of the prediction. 展开更多
关键词 Ti-15-3 alloy WRINKLING convex flange rubber forming quantitative analysis
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MICRO MECHANICAL ANALYSIS OF 3-D WOVEN COMPOSITES 被引量:2
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作者 周光明 周储伟 王新峰 《Transactions of Nanjing University of Aeronautics and Astronautics》 EI 2004年第3期163-167,共5页
A micro mechanical model is carried out to predict micro stresses and macro elastic properties of 3-D woven composites. A unit cell is composed of two phases. One is fiber yarn and the other is resin or fiber yarn in ... A micro mechanical model is carried out to predict micro stresses and macro elastic properties of 3-D woven composites. A unit cell is composed of two phases. One is fiber yarn and the other is resin or fiber yarn in transverse. The additional shearing introduced by bending of fiber yarn is considered. The method to determine the microstructure is also discussed. This model is applied to the analysis of a 3-D woven graphite/epoxy composite. Micro stresses of the cell are studied, and then macro modulus is obtained by employing the average method. The predictions agree well with experimental results. 展开更多
关键词 micro mechanics 3-D woven composites Galerkin method
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A DSS DEVELOPMENT AND APPLICATION FOR SUSTAINABLE DEVELOPMENT
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作者 沈惠璋 王浣尘 +2 位作者 刘铎 亢政刚 丁雷 《Transactions of Tianjin University》 EI CAS 2000年第1期22-27,共6页
The characteristics of sustainable development problems in the developing countries is discussed.In order to develop and use decision support system (DSS) for supporting sustainable development problem decision making... The characteristics of sustainable development problems in the developing countries is discussed.In order to develop and use decision support system (DSS) for supporting sustainable development problem decision making in the developing countries,this paper presents a strategy of constructing the DSS for sustainable development.A methodology of representing the model of sustainable development problems and developing a nonprocedural modeling language that is used to define sustainable development problems,a methodology of numeric and non numeric operation based theorem proving is given in this paper. 展开更多
关键词 decision support system sustainable development qualitative analysis quantitative research evolution behaviors
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A Dual Wavelength Differential First Derivative Spectrophotometric Method for Identification and Determination of Carbon Monoxide Generated During the Microsomal Metabolism of Xenobiotics in vitro
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作者 徐宏祥 刘志强 《Journal of Chinese Pharmaceutical Sciences》 CAS 1997年第2期51-56,共6页
A dual wavelength differential first derivative spectrophotometric method has been developed to standardize the concentration of a saturated aqueous solution of carbon monoxide (CO) as the standard and to identify and... A dual wavelength differential first derivative spectrophotometric method has been developed to standardize the concentration of a saturated aqueous solution of carbon monoxide (CO) as the standard and to identify and to determine CO formed during the microsomal metabolism of xenobiotics in vitro. The method can significantly eliminate the background interference in the assay media and increase the quantitative accuracy and the sensitivity. There is a good linear relationship between CO concentration in the range of 2~10 μmol·L 1 CO and the distance D between the first derivative peak at 415 nm amd valley at 426 nm with r=0.9999(n=5),the regression equation being C (mmol·L 1 )=17.6D 0.4, the detection limit lower than 0.1 μmol·L 1 CO. The average recoveries of CO from the assay system and the sample were 102.1%, RSD=2.9% (n=7) and 79.7%, RSD=6.8% (n=12),respectively. The RSD of within day was 4.4%(n=18),and the RSD of day to day was 6.1%(n=16). By this method, four trihaloanilines and one trihalobenzene were tested, the results showed that only 2,4,5 trifluoroaniline could be converted to CO by the incubation with rat hepatic microsomes, NADPH and oxygen, the ability of phenobarbital or dexamethasone to induce rat hepatic microsomes to catalyze CO formation was 3 or 8 times higher than that of the control. 展开更多
关键词 Dual wavelength differential first derivative spectrophotometry Carbon monoxide Trifluoroaniline Drug metabolism Hepatic microsomes Cytochrome P 450
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Rice Repetitive DNA Sequence RRD3:a Plant Promoter and Its Application to RNA Interference
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作者 仲健 王宏斌 +2 位作者 张党权 刘兵 王金发 《Journal of Genetics and Genomics》 SCIE CAS CSCD 北大核心 2007年第3期258-266,共9页
Previously, a moderately repetitive DNA sequence (RRD3) was cloned from rice (Oryza sativa L.) by DNA renaturation kinetics. Sequence analysis revealed several conserved promoter motifs, including four TATA-boxes ... Previously, a moderately repetitive DNA sequence (RRD3) was cloned from rice (Oryza sativa L.) by DNA renaturation kinetics. Sequence analysis revealed several conserved promoter motifs, including four TATA-boxes and a CAAT-box, and promoter activity was shown in Escherichia coli and mammalian expression systems. Here, we inserted the RRD3 fragment into the plant promoter-capture vector, pCAMBIA1391Z, and examined whether the RRD3 fragment has promoter activity in plants. Transgenic tobacco and rice calli both showed β-glucuronidase (GUS) activity, indicating that RRD3 can act as a promoter in both monocot and dicot plants. Based on the promoter characteristic of RRD3, we designed a plant universal binary vector, pCRiRRD3, which is suitable for performing researches on plant RNA interference. This vector has two multiple cloning sites to facilitate sense and antisense cloning of the target sequence, separated by an intron fragment of 200 bp. The efficiency of the vector for gene silencing was assayed by histochemical and quantitative fluorometric GUS assays in transgenic tobacco. These research results suggested that this plant RNAi vector pCRiRRD3 can effectively perform gene silencing researches on both monocot and dicot plants. 展开更多
关键词 RRD3 PROMOTER GUS histochemical assay quantitative fluorometric GUS assay RNA interference
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Quantitative analysis of transforming growth factor beta 1 mRNA in patients with alcoholic liver disease 被引量:21
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作者 Wei-Xing Chen You-Ming Li Chao-Hui Yu Wei-Min Cai Min Zheng Feng-Chen,Department of Gastroenterology, The First Affiliated Hospital,Medical College of Zhejiang University,Hangzhou 310003,Zhejiang Province,China 《World Journal of Gastroenterology》 SCIE CAS CSCD 2002年第2期379-381,共3页
AIM: To investigate the expression of the transforming growth factor beta 1(TGF-beta 1) mRNA in different stages of alcoholic liver disease (ALD) and its clinical value. METHODS: One hundred and seven male alcoholics ... AIM: To investigate the expression of the transforming growth factor beta 1(TGF-beta 1) mRNA in different stages of alcoholic liver disease (ALD) and its clinical value. METHODS: One hundred and seven male alcoholics were grouped by clinical findings into four groups: alcohol abusers without liver impairment (n =22), alcoholic steatosis (n =30); alcoholic hepatitis (n=31); and alcoholic cirrhosis(n=24). Using peripheral blood mononuclear cells (PBMC) as samples the gene expression of TGF-beta 1 was examined quantitatively by reverse transcription polymerase chain reaction (RT-PCR) and dot blot. There are 34 healthy subjects served as control. RESULTS: The expression of TGF-beta 1 from all ALD patients was significantly greater than that in controls (1.320 +/- 1.162 vs 0.808 +/- 0.276, P【0.001). The differences of the expressions were significant between the patients from each groups (alcoholic steatosis, alcoholic hepatitis and alcoholic cirrhosis) and the controls (1.168 +/- 0.852, 1.462 +/- 1.657, 1.329 +/- 0.610 vs 0.808 +/- 0.276, P【0.050). No significant differences of TGF -beta 1 mRNA expression were observed between alcohol abusers without liver impairment and controls. The expressions in patients with alcoholic hepatitis and alcoholic cirrhosis were significantly greater than that in alcohol abusers respectively (1.462 +/- 1.657, 1.329 +/- 0.610 vs 0.841 +/- 0.706, P【0.050). No significant differences of TGF-beta 1 mRNA expression were observed between alcoholic fatty liver men and alcohol abusers. CONCLUSION: TGF-beta 1 expression level can be a risk factor for alcoholic liver disease and might be related to the inflammatory activity and fibrosis of the liver in patients. 展开更多
关键词 Humans Liver Diseases Alcoholic MALE RNA Messenger Transforming Growth Factor beta
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Quantitative analysis using ELISA of vascular endothelial growth factor and basic fibroblast growth factor in human colorectal cancer,liver metastasis of colorectal cancer and hepatocellular carcinoma 被引量:27
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作者 Muriel Mathonnet Bernard Descottes +3 位作者 Denis Valleix Francois Labrousse Véronique Truffinet Yves Denizot 《World Journal of Gastroenterology》 SCIE CAS CSCD 2006年第23期3782-3783,共2页
Angiogenesis consists of the sprouting of capillaries from pre-existing vessels. It is well-known that tumor growth is angiogenesis-dependent. Vascular endothelial growth factor (VEGF) and basic fibroblast growth fa... Angiogenesis consists of the sprouting of capillaries from pre-existing vessels. It is well-known that tumor growth is angiogenesis-dependent. Vascular endothelial growth factor (VEGF) and basic fibroblast growth factor (bFGF) stimulated vascular endothelial cell proliferation and are involved in the neoplastic angiogenesis of several types of tumors including those of the intestinal tract. Authors usually investigated VEGF and using immunohistochemistry bFGF protein expressions or Western blotting and VEGF and bFGF transcripts using reverse transcriptase Dolymerase chain reaction (RT-PCR). 展开更多
关键词 Vascular endothelial growth factor Basicfibroblast growth factor Colorectal cancer Hepatocellularcarcinomas
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Determination of anthraquinone prodrug and its hydrolytically active compounds using RP-HPLC
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作者 段艳冰 余佳 +1 位作者 刘海峰 吉民 《Journal of Southeast University(English Edition)》 EI CAS 2009年第1期128-131,共4页
In order to study the hydrolytic characterization of an anti-inflammatory prodrug ( RI-1 ) in vitro, an effective, accurate and reliable method for the simultaneous determination of the prodrug and its two hydrolyti... In order to study the hydrolytic characterization of an anti-inflammatory prodrug ( RI-1 ) in vitro, an effective, accurate and reliable method for the simultaneous determination of the prodrug and its two hydrolytic active compounds is developed using reverse phase high-performance liquid chromatography (RP-HPLC). The chromatographic separation is performed on an ODS-2 C18 column (250 mm × 4. 6 mm, 5.0 μm particle size) with a simple elution program. The mobile phase is V( methanol) : V(0. 1% phosphoric acid solution) =90:10 (adjust pH to 2. 3). A wavelength of 225 nm and a mobile phase flow rate of 1.0 mL/min are utilized for the quantitative analysis. Excellent linear behaviors over the investigated concentration ranges are observed with values of R2 higher than 0. 999 for all the analytes. The validated method is successfully applied to the simultaneous determination of the prodrug and its active components can be used to detect hydrolytic characterization in vitro. 展开更多
关键词 high-performance liquid chromatography (HPLC) quantitative analysis anthraquinone prodrug active components
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Gastrointestinal tract distribution of Salmonella enteritidis in orally in fected mice with a species-specific fluorescent quantitative polymerase chain reaction 被引量:12
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作者 Shu-Xuan Deng An-Chun Cheng +1 位作者 Ming-Shu Wang Ping Cao 《World Journal of Gastroenterology》 SCIE CAS CSCD 2007年第48期6568-6574,共7页
AIM: To identify and understand the regular distribution pattern and primary penetration site for Salmonella enteritidis (S. enteritidis) in the gastrointestinal tract. METHODS: Based on the species-specific DNA seque... AIM: To identify and understand the regular distribution pattern and primary penetration site for Salmonella enteritidis (S. enteritidis) in the gastrointestinal tract. METHODS: Based on the species-specific DNA sequence of S. enteritidis from GenBank, a species-specific real- time, fluorescence-based quantitative polymerase chain reaction (FQ-PCR) was developed for the detection of S. enteritidis. We used this assay to detect genomic DNA of S. enteritidis in the gastrointestinal tract, including duodenum, jejunum, ileum, cecum, colon, rectum, esophagus and stomach, from mice after oral infection. RESULTS: S. enteritidis was consistently detected in all segments of the gastrointestinal tract. The jejunum and ileum were positive at 8 h post inoculation, and the final organ to show a positive result was the stomach at 18 h post inoculation. The copy number of S. enteritidis DNA in each tissue reached a peak at 24-36 h post inoculation, with the jejunum, ileum and cecum containing high concentrations of S. enteritidis, whereas the duodenum, colon, rectum, stomach and esophagus had low concentrations. S. enteritidis began to decrease and vanished at 2 d post inoculation, but it was still present up to 5 d post inoculation in the jejunum, ileum andcecum, without causing apparent symptoms. By 5 d post inoculation, the cecum had significantly higher numbers of S. enteritidis than any of the other areas (P < 0.01), and this appeared to reflect its function as a repository for S. enteritidis. CONCLUSION: The results provided significant data for clarifying the pathogenic mechanism of S. enteritidis in the gastrointestinal tract, and showed that the jejunum, ileum and cecum are the primary sites of invasion in normal mice after oral infection. This study will help to further understanding of the mechanisms of action of S. enteritidis. 展开更多
关键词 Fluorescence-based quantitative polymerase chain reaction Gastrointestinal tract Salmonella enteritidis
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Relationship between settlements and topographical factors:An example from Sichuan Province,China 被引量:9
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作者 XI Chang-bai QIAN Tian-lu +2 位作者 CHI Yao CHEN Jie WANG Jie-chen 《Journal of Mountain Science》 SCIE CSCD 2018年第9期2043-2054,共12页
Terrain can influence the spatial distribution of settlements. Studies on the terrain characteristics of settlements can help to understand the effects of the environment on human activities. This paper provides a qua... Terrain can influence the spatial distribution of settlements. Studies on the terrain characteristics of settlements can help to understand the effects of the environment on human activities. This paper provides a quantitative analysis of the relationship between settlements and topographical factors. A statistically significant sample of residential locations and ASTER GDEM V2 were used to investigate terrain traits and settlements distributions. We selected eight topographical factors and introduced a practical concept, distributive entropy, into assessing the aggregation extent of the settlements' spatial distribution. The study showed that topography varies within the study area, and distributive entropy indicates that settlements have distinctive distribution tendency in statistic approach. According to the results of this study, mountain inhabitants prefer to settle in valleys. Additionally, with distributive entropy, residential suitability was divided to three levels: suitable, normal, and unsuited. The results showed that suitable area is small in Sichuan Province, accounting for 8.2%~29.9%; however, unsuited area is large, accounting for 33%~63.3%. 展开更多
关键词 SETTLEMENT Topographical factor Distributive entropy Spatial pattern GeographicalInformation System
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Quantitative Analysis of Moisture Effect on Black Soil Reflectance 被引量:8
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作者 LIU Huan-Jun ZHANG Yuan-Zhi +4 位作者 ZHANG Xin-Le ZHANG Bai SONG Kai-Shan WANG Zong-Ming TANG Na 《Pedosphere》 SCIE CAS CSCD 2009年第4期532-540,共9页
Several studies have demonstrated that soil reflectance decreases with increasing soil moisture content, or increases when the soil moisture reaches a certain content; however, there are few analyses on the quantitati... Several studies have demonstrated that soil reflectance decreases with increasing soil moisture content, or increases when the soil moisture reaches a certain content; however, there are few analyses on the quantitative relationship between soil reflectance and its moisture, especially in the case of black soils in northeast China. A new moisture adjusting method was developed to obtain soil reflectance with a smaller moisture interval to describe the quantitative relationship between soil reflectance and moisture. For the soil samples with moisture contents ranging from air-dry to saturated, the changes in soil reflectance with soil moisture can be depicted using a cubic equation. Both moisture threshold (MT) and moisture inflexion (MI) of soil reflectance can also be determined by the equation. When the moisture range was smaller than MT, soil reflectance can be simulated with a linear model. However, for samples with different soil organic matter (OM), the parameters of the linear model varied regularly with the OM content. Based on their relationship, the soil moisture can be estimated from soil reflectance in the black soil region. 展开更多
关键词 black soil quantitative analysis remote sensing soil moisture spectral reflectance
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Soluble Expression and Rapid Quantification of GFP-hepA Fusion Protein in Recombinant Escherichia coli 被引量:7
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作者 陈银 邢新会 +1 位作者 叶逢春 况莹 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2007年第1期122-126,共5页
To establish a rapid quantification method for heparinase I during its production in recombinant Escherichia coli, a translational fusion vector was constructed by fusing the N terminus of heparinase I to the C termin... To establish a rapid quantification method for heparinase I during its production in recombinant Escherichia coli, a translational fusion vector was constructed by fusing the N terminus of heparinase I to the C terminus of a green fluorescent protein mutant (GFPmutl). As a result, not only was the functional recombinant expression of heparinase I in E. coli accomplished, but also a linear correlation was obtained between the GFP fluorescence intensity and heparinase I activity, allowing enzyme activity to be quantified rapidly during the fermentation. 展开更多
关键词 functional expression fusion protein green fluorescent protein (GFP) heparinase I rapid quantification
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Texture features analysis on micro-structure of paste backfill based on image analysis technology 被引量:7
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作者 YIN Sheng-hua SHAO Ya-jian +2 位作者 WU Ai-xiang WANG Yi-ming GAO Zhi-yong 《Journal of Central South University》 SCIE EI CAS CSCD 2018年第10期2360-2372,共13页
The strength of cement-based materials,such as mortar,concrete and cement paste backfill(CPB),depends on its microstructures(e.g.pore structure and arrangement of particles and skeleton).Numerous studies on the relati... The strength of cement-based materials,such as mortar,concrete and cement paste backfill(CPB),depends on its microstructures(e.g.pore structure and arrangement of particles and skeleton).Numerous studies on the relationship between strength and pore structure(e.g.,pore size and its distribution)were performed,but the micro-morphology characteristics have been rarely concerned.Texture describing the surface properties of the sample is a global feature,which is an effective way to quantify the micro-morphological properties.In statistical analysis,GLCM features and Tamura texture are the most representative methods for characterizing the texture features.The mechanical strength and section image of the backfill sample prepared from three different solid concentrations of paste were obtained by uniaxial compressive strength test and scanning electron microscope,respectively.The texture features of different SEM images were calculated based on image analysis technology,and then the correlation between these parameters and the strength was analyzed.It was proved that the method is effective in the quantitative analysis on the micro-morphology characteristics of CPB.There is a significant correlation between the texture features and the unconfined compressive strength,and the prediction of strength is feasible using texture parameters of the CPB microstructure. 展开更多
关键词 microstructure texture feature Tamura texture GLCM feature unconfined compressive strength quantitative analysis cement paste backfill
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