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Construction of the Government Support and Evaluation Index System of Farmers' Cooperative Economic Organizations
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作者 SUN Hao-jie1,WANG Zheng-bing2,WANG Yun-hui3 1.School of Economics and Management,Chang’an Univerity,Xi’an 710064,China 2.College of Economics and Management,Northwest A&F University,Yangling 712100,China 3.Department of Publicity,Xi’an Branch of Bank of China,Xi’an 710075,China 《Asian Agricultural Research》 2011年第5期84-87,99,共5页
On the basis of expounding the necessity of evaluation index system of farmers' cooperative economic organization,the three first level indexes including organization development index,member development index and... On the basis of expounding the necessity of evaluation index system of farmers' cooperative economic organization,the three first level indexes including organization development index,member development index and social development index and 13 second level indexes including aggregate capital of cooperative organization,annual profit share of cooperative organization,annual total income of cooperative organization,etc.,are established according to the principles of Systematics and the methods of Statistics and Quantitative economics.By using the analytical hierarchy process,the weight of each index is tested and the operation result and evaluation mode is established,as well as the index standard value and comprehensive value.As for the result of the evaluation,it is suggested that the government should support the farmers' cooperative organizations in hierarchy and targeted way according to local conditions.Though the construction of index system and comprehensive score,the government should establish the entry and exit mechanism of farmers' cooperative organizations to reasonably guild the rapid development of cooperators. 展开更多
关键词 Farmers’ COOPERATIVE ECONOMIC organIZATION Governm
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Safety Evaluation of Myricetin and Crude Extract from Myrica rubra Leaves on Non-target Organisms
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作者 李桥 徐静 +2 位作者 张绍勇 张旭 陈安良 《Plant Diseases and Pests》 CAS 2010年第4期46-50,共5页
[ Objective] The study aimed to supply important basis for developing environment-friendly pesticides with myricetin and crude extract of Myrica rubra leaves as effective components. [ Method] According to "Test guid... [ Objective] The study aimed to supply important basis for developing environment-friendly pesticides with myricetin and crude extract of Myrica rubra leaves as effective components. [ Method] According to "Test guidelines for environmental safety evaluation on chemical pesticides", the toxicity of myricetin and crude extract of M. rubra leaves on non-target organisms was determined and the safety evaluation was carried out. [Result] MyriceUn and crude extract of M. rubra leaves had low toxicity on non-target organisms, such as earthworm, silkworm and soil microbes. Myricetin showed low toxicity and the crude extract of M. rubra leaves showed middle toxicity on tadpole. The high-concentration crude extract of M. rubra leaves had some antifeedant effect on silkworm. [ Conclusion] Myricetin and crude extract of M. rubra leaves had low toxicity on non-tar- get organisms in environment and they were relatively safe. 展开更多
关键词 MYRICETIN Crude extract of M. rubra leaves Non-target organisms Safety evaluation
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Overall Evaluation of Organic Paddy Soil Fertility
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作者 刘亚柏 《Agricultural Science & Technology》 CAS 2014年第12期2138-2140,共3页
[Objective] The aim was to explore soil quality and fertility of organic rice fields in Daizhuang Village. [Method] The analysis was made based on soil samples from different areas where planting methods varied after ... [Objective] The aim was to explore soil quality and fertility of organic rice fields in Daizhuang Village. [Method] The analysis was made based on soil samples from different areas where planting methods varied after harvest of organic rice. [Result] The content of organic matter improved generally in fields of organic rice in Daizhuang. Specifically, the contents of N, P and K were not high, and the contents of N and P declined in the fields with crop rotation of organic rice Astragalus sin# cus, but the content of K increased. [Conclusion] It is of great significance for soil fertility to develop and promote crop rotation of organic rice Astragalus sinicus, which also advances quality of organic rice. 展开更多
关键词 organic rice Soil fertility Overall evaluation
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Evaluation of sugar and organic acid composition and their levels in highbush blueberries from two regions of China 被引量:9
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作者 ZHANG Jia NIE Ji-yun +5 位作者 LI Jing ZHANG Hui LI Ye Saqib FAROOQ Syed Asim Shah BACHA WANG Jie 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2020年第9期2352-2361,共10页
Sweet and sour are the most important taste of blueberries,and they are produced by sugar and acid,respectively.Their contributions to the taste depend not only on the levels of sugar and acid,but also on the types an... Sweet and sour are the most important taste of blueberries,and they are produced by sugar and acid,respectively.Their contributions to the taste depend not only on the levels of sugar and acid,but also on the types and relative proportions of sugar and acid.Therefore,it is very important to evaluate the composition and levels of sugar and acid in blueberries.Regional differences and variety diversity also affect the sugar and acid characteristics of fruits.Therefore,this study selected two main producing regions in northern China(Weihai and Yingkou)to examine the sugar and acid characteristics of 11 common blueberry cultivars.The indexes measured included soluble sugars,organic acids,soluble solid content and titratable acidity.The results showed that glucose and fructose were the major sugars,and citric acid and quinic acid were the major organic acids.Correlation analysis showed that glucose,fructose,and sucrose were positively correlated with total sugar content;the citric acid content was positively correlated with the titratable acidity and total organic acids.Titratable acidity,glucose,fructose,sucrose,total sugar content,citric acid,shikimic acid and total acid content of the blueberries varied significantly between regions(P<0.05).In general,compared with Weihai blueberries,Yingkou blueberries had higher sugar content and lower acid content.The results of this study may provide useful references for the evaluation of sweet and sour flavors and cultivar selection of blueberries. 展开更多
关键词 BLUEBERRY SUGAR organic acid level evaluation
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Fast Evaluation of Degradation Degree of Organic Coatings by Analyzing Electrochemical Impedance Spectroscopy Data 被引量:21
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作者 XIA Dahai SONG Shizhe +2 位作者 WANG Jihui BI Huichao HAN Zhewen 《Transactions of Tianjin University》 EI CAS 2012年第1期15-20,共6页
The degradation coefficient is proposed to evaluate the degradation degree of organic coatings by directly anaIyzing the Bode plots of the electrochemical impedance spectroscopy (EIS) data. This paper investigated t... The degradation coefficient is proposed to evaluate the degradation degree of organic coatings by directly anaIyzing the Bode plots of the electrochemical impedance spectroscopy (EIS) data. This paper investigated the degradation of phenolic epoxy coating/tinplate system by EIS and the degradation coefficient value, which correlates well with the results of breakpoint frequency and variation of phase angle at 10 Hz. Furthermore, the degradation process was confirmed by scanning electron microscope (SEM) and scanning probe microscopy (SPM). It is concluded that degradation coefficient can be used for the fast evaluation of degradation degree of organic coatings in practical appli- cations. 展开更多
关键词 degradation process electrochemical impedance spectroscopy fast evaluation organic coating
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Synthesis and Performance Evaluation of Organic Bentonite Modifier Dimethyldistearylammonium Bromide (DODMAB) 被引量:2
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作者 Qingwang Liu Ao Sun +3 位作者 Zhenzhong Fan Jiguang Wang Tong Zhang Dong Cheng 《Open Journal of Composite Materials》 2014年第4期220-223,共4页
Dimethyldistearylammonium Bromide (DODMAB) is a bentonite modifier with good performance. In this experiment, 1-Bromooctadecane is the raw material, and completes tertiary amination and quaternization successively by ... Dimethyldistearylammonium Bromide (DODMAB) is a bentonite modifier with good performance. In this experiment, 1-Bromooctadecane is the raw material, and completes tertiary amination and quaternization successively by changing the condition of experiment. The result is that the productivity can achieve 78.94% in the synthesis of DODMAB. It has been used in the experiment of bentonite modification and achieves good results;compared with using trimethylstearylammonium bromide as the organic modifier, the synthetic organic bentonite has better performance than the common organic modifier when used in the oil base drilling fluid of oilfield operation. 展开更多
关键词 organic MODIFIER STEPWISE SYNTHESIS Performance evaluation
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Self-organizing fuzzy clustering neural network and application to electronic countermeasures effectiveness evaluation 被引量:6
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作者 Li Zhisheng Li Junshan +1 位作者 Feng Fan Zhao Xin 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2008年第1期119-124,共6页
A self-organizing fuzzy clustering neural network by combining the self-organizing Kohonen clustering network with the fuzzy theory is proposed. This network model is designed for the effectiveness evaluation of elect... A self-organizing fuzzy clustering neural network by combining the self-organizing Kohonen clustering network with the fuzzy theory is proposed. This network model is designed for the effectiveness evaluation of electronic countermeasures, which not only exerts the advantages of the fuzzy theory, but also has a good ability in machine learning and data analysis. The subjective value of sample versus class is computed by the fuzzy computing theory, and the classified results obtained by self-organizing learning of Kohonen neural network are represented on output layer. Meanwhile, the fuzzy competition learning algorithm keeps the similar information between samples and overcomes the disadvantages of neural network which has fewer samples. The simulation result indicates that the proposed algorithm is feasible and effective. 展开更多
关键词 fuzzy clusteringself-organizing neural network effectiveness evaluation
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Establishment and Evaluation of a Method for Analyzing Atmospheric Volatile Organic Compounds
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作者 孙扬 王跃思 +2 位作者 修天阳 王迎红 徐新 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2007年第4期679-687,共9页
An automated cumulative sampling system and a method that combines a two-step cryo-concentrated system and gas chromatography/mass spectrometry (CCS-GC/MS) are introduced. The method is evaluated by a set of special... An automated cumulative sampling system and a method that combines a two-step cryo-concentrated system and gas chromatography/mass spectrometry (CCS-GC/MS) are introduced. The method is evaluated by a set of special experiments and the results are presented. The lowest measurement detection limit was expanded from 10^-6 nmol mol^-1 to 10^-12 nmol mol^-1 by using CCS-GC/MS instead of the simpler method of gas chromatography/mass spectrometry (GC/MS), with the average responsible factor of 39 object compounds being 2.9 × 10^-12. When the volume of air sample reached 1000 cm^3, the lowest detection limit reached up to 7 × 10^-12-40 × 10^-12 nmol mol^-1. The CCS-GC/MS method can potentially identify all objective chemical species in an atmospheric sample, with an average 2.5 s bias error of retention time for 39 gas chromatography (GC) peaks. Within the range 0-400×10^-9 nmol mol^-1, the concentration of 39 kinds of objective compounds can be individually calculated very accurately by a standard curve [average r^2 (coefficient of determination) value of above 0.99]. The recovery efficiency was 88%-111%, with an average of 100.8% ±5.6%. The bias error of precision was 2%-14%, with an average of 6.6%. 展开更多
关键词 ATMOSPHERE cryo-concentration volatile organic compounds (VOCs) evaluation bias error
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Organic geochemical evaluation of the oil/gas-generative potential of organic matter in Cretaceous strata from the Lower Benue Trough,Nigeria
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作者 Minapuye I.Odigi Levi C.Amajor 《Chinese Journal Of Geochemistry》 EI CAS 2010年第3期233-241,共9页
An analytical procedure involving Rock-Eval pyrolysis of whole-rocks was adopted on fresh outcrop samples covering the three lithostratigraphic units in the Afikpo Basin of the Lower Benue Trough. Three petroleum syst... An analytical procedure involving Rock-Eval pyrolysis of whole-rocks was adopted on fresh outcrop samples covering the three lithostratigraphic units in the Afikpo Basin of the Lower Benue Trough. Three petroleum systems are present in the Cretaceous delta frame: the Asu-River Group, the Eze-Aku Group and proto-Niger Delta sequences. The Afikpo Basin has been correlated to three petroleum systems in the Lower Congo Basin, Niger Delta and the Anambra Basin. The organic geochemistry of the shales, carbonaceous mudstones and coal beds show relatively moderate to high total organic carbon contents. The best potential hydrocarbon source rocks are the Eze-Aku Group and proto-Niger Delta shales, carbonaceous mudstones and coal beds where maturation was attained. The high total organic contents, thermal maturity and terrigenous characters of the Asu-River Group, Eze-Aku Group and proto-Niger Delta sediments, suggest the presence of a large amount of natural gas with a small quantity of oil accumulation. Variations in source rock facies were observed from one lithostratigraphic unit to another, and initial HI values as a function of TOC were proposed for each lithostratigraphic unit. The results also show that TOC, HI, OI, S2 and Tmax vary from older to younger rocks. The Tmax values discriminate the rocks into immature and mature source rocks. Source rocks with high Tmax suggest high geothermal gradient/or recycled organic matter. Also high Tmax and S2 yield indicate late and post maturity. Recycled organic matter is characterized by low Tmax. The principal source rocks for gas in the Afikpo Basin are the Eze-Aku Group and proto-Niger Delta beds deltaic systems, consisting mainly of III to IV kerogens with a subordinate amount of type II organic matter. Based on the obtained results, it is concluded that the Cretaceous shales, carbonaceous mudstones and coals in the Afikpo Basin of the Lower Benue Trough are capable of generating and expelling hydrocarbons in the case of sufficient maturity. 展开更多
关键词 岩石地层单位 有机物质 地球化学评价 尼日利亚 尼日尔三角洲 白垩系 热成熟度 含油气系统
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Characteristics of Heavy Metals and Their Evaluation in Sediments from Middle and Lower Reaches of the Huaihe River 被引量:6
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作者 YAN Jia-ping HE Yong HUANG He 《Journal of China University of Mining and Technology》 EI 2007年第3期414-417,共4页
We have collected 18 samples corresponding to 18 locations in the middle and lower reaches of the Huaihe River. The sediment samples were tested for their pH level,percentage of solids,organic matter and five heavy me... We have collected 18 samples corresponding to 18 locations in the middle and lower reaches of the Huaihe River. The sediment samples were tested for their pH level,percentage of solids,organic matter and five heavy metals (Cr,Cu,Zn,Cd and Pb). The average concentrations of Cr,Cu,Zn,Cd and Pb of the 18 sampling locations were re-spectively 56.1,22.2,70.0,0.17 and 20.4 μg/g. Compared with their background values,the average concentrations of Zn and Cu in sediment samples from the Huaihe River were slightly higher,while the average concentrations of Cr and Pb were slightly lower. The concentration of Cd in all sediment samples was higher than its background value,while the average concentration of Cd in all sediment samples was about twice the amount of the background value. The concen-tration of the five heavy metals was lower than that of the Yangtze River. A correlation analysis revealed that heavy metals have similar geochemical feautures. The geo-accumulation index (Igeo) was used to evaluate the degree of pollu-tion of the Huaihe River sediments. The index reveals that the sediment samples are largely ranked from zero pollution to no to medium pollution. 展开更多
关键词 evaluation heavy metal Huaihe River organic matter SEDIMENT
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Evaluation indices of sour flavor for apple fruit and grading standards 被引量:7
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作者 YAN Zhen ZHENG Li-jing +2 位作者 NIE Ji-yun LI Zhi-xia CHENG Yang 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2018年第5期994-1002,共9页
In order to establish grading standards of evaluation indices for sour flavor of apples, 10 indices of samples from 106 apple cultivars were tested, including: malic acid(Mal), oxalic acid(Oxa), citric acid(Cit... In order to establish grading standards of evaluation indices for sour flavor of apples, 10 indices of samples from 106 apple cultivars were tested, including: malic acid(Mal), oxalic acid(Oxa), citric acid(Cit), lactic acid(Lac), succinic acid(Suc), fumaric acid(Fum), total organic acids(To A, the sum of the six organic acids tested), titratable acid(TiA), acidity value(AcV), and pH value. For most of the cultivars studied(85.8%), the order of the organic acid contents in apples was Mal〉Oxa〉Cit〉Lac〉Suc〉Fum. Mal was the dominant organic acid, on average, accounting for 94.5% of To A. Among the 10 indices, the dispersion of pH value was the smallest with a coefficient of variation of only 8.2%, while the coefficients of variation of the other nine indices were larger, ranging between 31 and 66%. There were significant linear relationships between Mal and two indices(ToA and AcV) as well as between ToA and AcV. There were significant logarithmic relationships between pH value and four indices: Mal, TiA, ToA, and AcV. All the equations had very high fitting accuracy and can be used to accurately predict related indices. According to this study, Mal, ToA, and AcV of apple were normally distributed, TiA was close to normally distributed, whereas pH value had a skewed distribution. Using the fitted normal distribution curves, the grading standards of Mal, TiA, ToA, and AcV were established. The grading node values of pH value were obtained using the logarithmic relationship between pH value and Mal. The grading standards of these five indices can be used to evaluate the sour flavor of apple. This study provides a scientific basis for evaluating apple flavor and selecting apple cultivars. 展开更多
关键词 apple organic acid sour flavor evaluation indices grading standard
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New approaches for precise response evaluation in hepatocellular carcinoma 被引量:4
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作者 Koichi Hayano Jorge M Fuentes-Orrego Dushyant V Sahani 《World Journal of Gastroenterology》 SCIE CAS 2014年第12期3059-3068,共10页
With the increasing clinical use of cytostatic and novel biologic targeted agents,conventional morphologic tumor burden assessments,including World Health Organization criteria and Response Evaluation Criteria in Soli... With the increasing clinical use of cytostatic and novel biologic targeted agents,conventional morphologic tumor burden assessments,including World Health Organization criteria and Response Evaluation Criteria in Solid Tumors,are confronting limitations because of their difficulties in distinguishing viable tumor from necrotic or fibrotic tissue.Therefore,the investigation for reliable quantitative biomarkers of therapeutic response such as metabolic imaging or functional imaging has been desired.In this review,we will discuss the conventional and new approaches to assess tumor burden.Since targeted therapy or locoregional therapies can induce biological changes much earlier than morphological changes,these functional tumor burden analyses are very promising.However,some of them have not gone thorough all steps for standardization and validation.Nevertheless,these new techniques and criteria will play an important role in the cancer management,and provide each patient more tailored therapy. 展开更多
关键词 Hepatocellular carcinoma World Health organization criteria Response evaluation Criteria in Solid Tumors European Association for the Study of Liver Computed tomography perfusion Dynamic contrast-enhanced-magnetic resonance imaging Diffusion-weighted imaging Positron emission tomography
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Study and application of Toxicity Test Method Using Neomysis awatschensis in Toxicity Evaluation of Drilling Fluid 被引量:1
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作者 颜天 周名江 +3 位作者 谭志军 于仁诚 李钧 王云峰 《Marine Science Bulletin》 CAS 2002年第1期71-75,共5页
Neomysis awatschensis was collected on the west coast of Jiaozhou Bay, Qingdao in 1992 and acclimated in the laboratory conditions. The acute toxicity method using 4~ 6 day juvenile mysid of this species is studied. T... Neomysis awatschensis was collected on the west coast of Jiaozhou Bay, Qingdao in 1992 and acclimated in the laboratory conditions. The acute toxicity method using 4~ 6 day juvenile mysid of this species is studied. The species is compared with M. bahia in taxonomy, geographic distribution, morphology, as well as the sensitivity to reference toxins. Based on the results, we recommend N. awatschensis to be a standard marine organism for toxicity test in China and the method to be applied in toxicity evaluation of drilling fluids. In this paper, we report the results of the above studies and the application of the method in the evaluation of several drilling fluid products. 展开更多
关键词 Neomysis awatschensis toxicity evaluation standard organism drilling fluid
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Hydrocarbon generation and organic matter enrichment of limestone in a lacustrine mixed sedimentary environment: A case study of the Jurassic Da'anzhai member in the central Sichuan Basin, SW China 被引量:1
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作者 Qi-Lu Xu Bo Liu +4 位作者 Xin-Min Song Qing-Ping Wang Xu-Dong Chen Yang Li Yu Zhang 《Petroleum Science》 SCIE EI CAS CSCD 2023年第2期670-688,共19页
The hydrocarbon generation effectiveness of lacustrine limestone has been gradually proven. The Da'anzhai Member limestone is the most important Jurassic oil-producing layer in the central Sichuan Basin, and the c... The hydrocarbon generation effectiveness of lacustrine limestone has been gradually proven. The Da'anzhai Member limestone is the most important Jurassic oil-producing layer in the central Sichuan Basin, and the characteristics of limestone organic matter are often overlooked. 175 typical samples of different lithologies from 19 wells were systematically analyzed to determine hydrocarbon generation, controlling factors and formation models by analyses of organic matter, minerals, elements, isotopes and petrography. (1) Lacustrine paleoenvironments can be beneficial for the enrichment of organic matter in limestone. A favorable environment would be a quiet, low-energy zone in a warm and humid climate with an appropriate supply of terrestrial inputs. (2) Lacustrine limestone has a higher organic matter conversion rate, and a lower hydrocarbon generation threshold than argillaceous source rocks, and can be effective source rock. (3) The mud-bearing shell limestone from the forebeach to the lake slope is thick, with a relatively high abundance of organic matter, and its hydrocarbon generation is effective. This study can clarify the effectiveness and enrichment of the limestone organic matters in the study area, and contribute to an understanding of hydrocarbon generation for full-rock system in a lacustrine mixed sedimentary environment. 展开更多
关键词 Lacustrine limestone Full-rock system organic matter evaluation PALEOENVIRONMENTS Lake evolution Terrestrial inputs
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Study on the Manufacturability Evaluation Based on Double-layer Model of Manufacturing Resources
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作者 石旭东 FU +4 位作者 Yili Dai Yong Ma Yulin 《High Technology Letters》 EI CAS 2001年第2期61-65,共5页
Virtual organization is a new production patter and a principal part in advanced manufacturing systems such as agile manufacturing. Manufacturability evaluation is the necessary condition to form the virtual organizat... Virtual organization is a new production patter and a principal part in advanced manufacturing systems such as agile manufacturing. Manufacturability evaluation is the necessary condition to form the virtual organization. A new manufacturability evaluation approach is described in this paper, which is carried out based on every process feature under the double-layer model of manufacturing resources proposed by authors. The manufacturing resources that build up the virtual organization are selected according to the results of manufacturability evaluation. 展开更多
关键词 Manufacturability evaluation Double-layer model of manufacturing resources Virtual organization
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Water Quality Evaluation and Analysis on the Causes of Pollution for Groundwater Sources in Yantai, China
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作者 PanpanMeng Henghua Zhu +1 位作者 Jing Wang Baoping Lv 《Journal of Environmental Science and Engineering(A)》 2015年第2期99-103,共5页
Based on the investigation for the 14 groundwater sources, the water quality of the groundwater sources had been analyzed, using the evaluation method of the combination of inorganic and organic index instead of the t... Based on the investigation for the 14 groundwater sources, the water quality of the groundwater sources had been analyzed, using the evaluation method of the combination of inorganic and organic index instead of the traditional method which was only based on inorganic index. The results showed that the quality of 12 groundwater sources satisfied class III standard of groundwater quality and other two exceeded class III standard. There were one groundwater source, whose water quality reached class 1 standard, and five groundwater sources, whose water quality reached class II standard. There were seven groundwater sources, in which the fluorine, an organic pollutant, was detected. The results showed that the groundwater resources in Yantai City were less polluted and the main pollutant in groundwater was nitrate. According to the analytical data and the environmental conditions of groundwater sources, the conclusion was drawn that the agriculture and rural non-point pollution were the main reasons of groundwater pollution. 展开更多
关键词 Groundwater sources water quality evaluation groundwater pollution organic pollution analysis.
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鄂尔多斯盆地南缘长7烃源岩地球化学特征与沉积环境
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作者 王广利 李阳阳 +1 位作者 王一帆 高兴 《中国石油大学学报(自然科学版)》 EI CAS CSCD 北大核心 2024年第1期91-103,共13页
鄂尔多斯盆地南缘出露多处典型长7段页岩剖面,为了加深该区域烃源岩的研究,对35个烃源岩样品开展有机碳含量测定、岩石热解分析、饱和烃气相色谱-质谱分析、微量元素含量测定等测试分析,研究其地球化学特征,分析其有机质来源及沉积环境... 鄂尔多斯盆地南缘出露多处典型长7段页岩剖面,为了加深该区域烃源岩的研究,对35个烃源岩样品开展有机碳含量测定、岩石热解分析、饱和烃气相色谱-质谱分析、微量元素含量测定等测试分析,研究其地球化学特征,分析其有机质来源及沉积环境。结果表明:暗色页岩发育于淡水和还原的半深湖—深湖环境,沉积期气候温暖湿润,适宜生物发育,Mo元素高度富集,指示湖泊富营养化,初级生产力高;物质来源为藻类等低等水生生物和陆地植物的混合来源,但藻类等低等水生生物是主要来源;源岩有机质高度富集,总有机碳(TOC)平均值为23.51%,高于陆相优质烃源岩的丰度标准;有机质以腐泥—混合型为主,生烃潜量S1+S2均值为112.93 mg/g,生烃潜力良好;岩石热解峰温及生物标志化合物参数,指示达到成熟热演化程度,具有勘探潜力。 展开更多
关键词 鄂尔多斯盆地 铜川地区 有机地球化学特征 烃源岩评价 有机质来源 沉积环境
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气相色谱-离子迁移谱技术在蜂蜜品质鉴评中的应用
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作者 龙道崎 刘振平 +5 位作者 甘芳瑗 张学健 夏晓华 姜容 庞钶靖 聂青玉 《食品工业科技》 CAS 北大核心 2024年第13期402-410,共9页
蜂蜜具有丰富的营养成分和广泛的生物活性,但由于蜂蜜植物来源、地理来源、昆虫来源、成熟程度等的不同,蜂蜜在其内源成分和营养价值上表现出显著差异。挥发性有机化合物(volatile organic compounds,VOCs)与蜂蜜的特征属性密切相关,可... 蜂蜜具有丰富的营养成分和广泛的生物活性,但由于蜂蜜植物来源、地理来源、昆虫来源、成熟程度等的不同,蜂蜜在其内源成分和营养价值上表现出显著差异。挥发性有机化合物(volatile organic compounds,VOCs)与蜂蜜的特征属性密切相关,可用于表征蜂蜜间的差异。气相色谱-离子迁移谱联用技术(gas chromatography-ion mobility spectroscopy,GC-IMS)是一种将气相色谱技术与离子迁移谱技术相结合用于VOCs测定的新技术。近年来,GC-IMS被逐步应用于蜂蜜蜂种鉴定、产地溯源、植物来源区分、掺假鉴别、成熟度区分等方面,并均取得了较好的效果,在蜂蜜品质鉴评方面表现出了较大的应用潜力。本文收集了目前的文献资料,综述了GC-IMS在蜂蜜品质分析鉴别方面的应用研究进展,提出未来可考虑从建立蜂蜜GC-IMS数据库、研发融合定量功能的GCIMS设备、开发基于GC-IMS的质量评价技术标准以及GC-IMS与其他风味检测技术联用等方面进行深入研究,以期为GC-IMS技术在蜂蜜的品质控制、风味研究、产品开发等方面提供参考。 展开更多
关键词 气相色谱-离子迁移谱 蜂蜜 品质鉴评 挥发性有机化合物
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页岩无机孔和有机孔的渗透率计算方法
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作者 李亚军 李惊鸿 +2 位作者 桑茜 董明哲 崔传智 《特种油气藏》 CAS CSCD 北大核心 2024年第4期126-132,共7页
针对页岩储层无机孔隙和有机孔隙共存的问题,运用双重连续介质方法,结合油相和水相在页岩无机孔隙和有机孔隙中的润湿性和渗流特征,得到油相和水相在页岩中的渗流数学模型。基于该模型拟合页岩油水自吸实验结果,分别得到了页岩的无机孔... 针对页岩储层无机孔隙和有机孔隙共存的问题,运用双重连续介质方法,结合油相和水相在页岩无机孔隙和有机孔隙中的润湿性和渗流特征,得到油相和水相在页岩中的渗流数学模型。基于该模型拟合页岩油水自吸实验结果,分别得到了页岩的无机孔渗透率和有机孔渗透率,实现了对页岩储层含油量的准确计算,研究了页岩渗流过程的动态特征和影响规律。结果表明:无机孔渗透率为10^(-8)~10^(-5)D,有机孔渗透率为10^(-10)~10^(-7)D;随无机孔渗透率、有机孔渗透率的增加,页岩自吸速率加快;当有机孔渗透率与无机孔渗透率比值小于10^(-3)时,有机孔渗透率对自吸速率的影响不显著。研究成果对页岩储层渗透率和储量的精细评价具有重要指导意义。 展开更多
关键词 页岩 双重连续介质 无机孔渗透率 有机孔渗透率 储量评价
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基于三维质量结构理论构建心脏移植手术护理质量评价指标体系
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作者 张莹 孙立群 +5 位作者 赵海运 金子 王宇 郝璀璨 魏薇 张增梅 《河南医学研究》 CAS 2024年第17期3088-3093,共6页
目的构建心脏移植手术患者护理质量评价指标体系,为护理质量的监测及管理提供参考依据。方法基于三维质量结构理论,通过文献检索、质性访谈、组内会议、德尔菲专家咨询等方法制定评价指标体系。结果最终形成的心脏移植手术护理质量评价... 目的构建心脏移植手术患者护理质量评价指标体系,为护理质量的监测及管理提供参考依据。方法基于三维质量结构理论,通过文献检索、质性访谈、组内会议、德尔菲专家咨询等方法制定评价指标体系。结果最终形成的心脏移植手术护理质量评价指标体系中包含3项一级指标及12项二级指标、82项三级指标。两轮函询问卷有效回收率分别为90.48%、100.00%,权威系数分别为0.887、0.895,肯德尔和谐系数分别为0.206、0.245。结论该评价指标体系科学、合理、客观、完整,可以为心脏移植围手术期护理质量评价提供参考依据。 展开更多
关键词 器官移植 围手术期护理 护理评价研究 德尔菲法
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