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法定食品分析方法的认证 被引量:1
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作者 刘绍忠 关婕 张印贞 《山东轻工业学院学报(自然科学版)》 CAS 1997年第1期71-73,80,共4页
简述了法定食品分析方法的认证内容,即对分析中的精密度、准确度、选择性、检测限度、定量检出限、线性和范围、耐用性等作了一定的阐述。
关键词 法定方法 规范 认证 食品分析
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法定食品分析方法的认证
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作者 关婕 刘绍忠 《中国公共卫生》 CAS CSCD 北大核心 1997年第4期224-225,共2页
法定食品分析方法的认证广东省深圳市卫生防疫站(518020)关婕深圳市戒毒所刘绍忠法定分析方法是由权威机构颁布的具有一定法律地位的标准方法。WHO/FAO以及美国官方化学家协会(AOAC)颁布的食品标准分析方法在国际... 法定食品分析方法的认证广东省深圳市卫生防疫站(518020)关婕深圳市戒毒所刘绍忠法定分析方法是由权威机构颁布的具有一定法律地位的标准方法。WHO/FAO以及美国官方化学家协会(AOAC)颁布的食品标准分析方法在国际上享有较高的权威,但近年来各国及国... 展开更多
关键词 食品分析 法定分析方法 认证
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对三资企业出口产品法定检验方法改革的探讨 被引量:1
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作者 孙凤鸣 《现代商检科技》 1997年第2期32-34,共3页
关键词 三资企业 出口商品 法定检验方法 商品检验
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生活事件评分方法作为心理症状学指标的比较研究 被引量:3
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作者 ZuckermanLA etal.J.HumanStress 《中国心理卫生杂志》 1987年第1期28-28,共1页
生活事件调查表(LES)的七种评分方法,对其以简要症状询问表(BSI)测定时,何种方法作为心理症状学指标最为优越作了比较研究。除根据个人正性生活事件评分方法外,其他六种方法都与症状学有显著相关性。而以个人负性生活事件评分较之其他... 生活事件调查表(LES)的七种评分方法,对其以简要症状询问表(BSI)测定时,何种方法作为心理症状学指标最为优越作了比较研究。除根据个人正性生活事件评分方法外,其他六种方法都与症状学有显著相关性。而以个人负性生活事件评分较之其他评分方法作为指标显得更为优异。从这些结果可得出以下结论:(1) 展开更多
关键词 生活事件 评分方法 心理症状 比较研究 症状学 法定方法 六种方法 询问表 显著相关 指示作用
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HPLC Determination of Harpagoside and Cinnamic Acid in Radix Scrophulariae 被引量:5
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作者 谢丽华 刘洪宇 +4 位作者 徐秉玖 王璇 王建华 徐风 蔡少青 《Journal of Chinese Pharmaceutical Sciences》 CAS 2001年第3期148-151,共4页
A gradient HPLC method was established for the determination of harpagoside and cinnamic acid in Radix Scrophulariae (Xuanshen) and a proposition was put forward for the lowest content of the characteristic and active... A gradient HPLC method was established for the determination of harpagoside and cinnamic acid in Radix Scrophulariae (Xuanshen) and a proposition was put forward for the lowest content of the characteristic and active constituent (harpagoside) for qualified Radix Scrophulariae. The experimental conditions were as follows: Ultrasphere ODS column (250 mm 4.6 mm, 5 mm), mobile phase: acetonitrile-water (containing 1.0% acetic acid) (20:8050:50) (20 min), flow-rate 1 mLmin-1, room temperature, detection wavelength 278 nm. Twenty-eight samples of Xuan-shen (Radix Scrophulariae) from different districts of China were analyzed and the contents of harpagoside and cinnamic acid in Xuan-shen were 0.041~0.244% and 0.012~0.068% respectively. The recoveries (RSD)% were 97.13(0.80)% for harpagoside and 99.38(0.51)% for cinnamic acid. The method is simple and accurate. It can be used for the quality control of Radix Scrophulariae. We propose that the content of harpagoside in qualified Radix Scrophularia should be no less than 0.05%. 展开更多
关键词 Scrophularia ningpoensis HARPAGOSIDE Cinnamic acid HPLC
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NOVEL IMMERSED BOUNDARY-LATTICE BOLTZMANN METHOD BASED ON FEEDBACK LAW 被引量:1
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作者 李秀娟 赵荣国 钟诚文 《Transactions of Nanjing University of Aeronautics and Astronautics》 EI 2012年第2期179-186,共8页
The lattice Boltzmann method (LBM) and the immersed boundary method (IBM) are alternative, com- putational techniques for solving complex fluid dynamics systems, and can take the place of the Navier-Stokes(N- S)... The lattice Boltzmann method (LBM) and the immersed boundary method (IBM) are alternative, com- putational techniques for solving complex fluid dynamics systems, and can take the place of the Navier-Stokes(N- S) equation. This paper proposes a novel immersed boundary-lattice Boltzmann method (IB-LBM) based on the feedback law. The method uses the immersed boundary concept in the LBM framework to capture the coupling between a body with complex geometry and a uniform fluid, Then, the flows around a stationary circular cylinder and two circular cylinders in a side by side arrangement are simulated by using the method. Results are agreed well with the benchmark data, so, the capability of the method for complex geometry is demonstrated. Different from the conventional IB-LBM, which uses the Hook's law or the direct forcing method to compute the interae- tion force, the method uses the feedback law--the feedback of velocity field and displacement information to calculate the force, thus ensuring the method has advantages of easy implementation and full parallelism. 展开更多
关键词 computational fluid dynamics lattice Boltzmann method immersed boundary method feedback law circular cylinder
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High-Performance Liquid Chromatographic Method for Determination of Germacrone in Rat Plasma 被引量:4
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作者 HEHai-bing TANGXing CUIFu-de 《Journal of Chinese Pharmaceutical Sciences》 CAS 2004年第3期190-192,共3页
Aim A reliable high-performance liquid chromatographic (HPLC) method wasdeveloped for determination of germacrone in rat plasma. Methods The plasma samples were treatedwith acetonitrile and analyzed by HPLC with UV de... Aim A reliable high-performance liquid chromatographic (HPLC) method wasdeveloped for determination of germacrone in rat plasma. Methods The plasma samples were treatedwith acetonitrile and analyzed by HPLC with UV detection at 244 nm. Results The limit of detectionwas 100 ng·mL^(-1) for germacrone in plasma and the linear range was 0.1004-15.06 μg·mL^(-1) inplasma. The RSD of intra-day and inter-day assay was 1.87% - 4.29% and 1.29% -5.15%, respectively.The recoveries of germacrone were over 95%. The endogenous substances in plasma did not show anyinterference in the analysis. Conclusion The method is accurate and convenient, and suitable forpharmacokinetic studies of germacrone in rats. 展开更多
关键词 high-performance liquid chromatography GERMACRONE volatile oil of rhizomacurcumae
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Identification of a Putative Tetrasporophyte-Specific Gene in Gracilaria lemaneiformis(Gracilariales,Rhodophyte) 被引量:2
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作者 REN Xueying ZHANG Xuecheng 《Journal of Ocean University of China》 SCIE CAS 2008年第3期299-303,共5页
A putative tetrasporophyte-specific gene,designated as SSH466(GenBank accession No. DQ019223) ,was one of the genes identified in this work using suppression subtractive hybridization(SSH) method in Gracilaria lemanei... A putative tetrasporophyte-specific gene,designated as SSH466(GenBank accession No. DQ019223) ,was one of the genes identified in this work using suppression subtractive hybridization(SSH) method in Gracilaria lemaneiformis. The full length of the gene was obtained using SMART RACE strategy. Sequence analysis revealed that the gene had 1 019 nucleotides,including an open reading frame of 498 nucleotides encoding 166 amino acid residues,158 nucleotides of 5' untranslated region and 363 nucleotides of 3' non-coding region. Protein motif and secondary structure prediction showed that there existed a transmembrane domain with a unique β-sheet. Thus,SSH466 protein might be a cross-membrane protein. Sequence homology search in the public GenBank databases did not reveal any significant match with SSH466. Virtual Northern blot analysis confirmed that it was a tetrasporophyte-specific gene. 展开更多
关键词 suppression subtractive hybridization (SSH) TETRASPOROPHYTE female gametophyte Virtual Northern blot
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Species concepts and biodiversity in Trichoderma and Hypocrea:from aggregate species to species clusters? 被引量:10
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作者 DRUZHININA Irina KUBICEK Christian P. 《Journal of Zhejiang University-Science B(Biomedicine & Biotechnology)》 SCIE CAS CSCD 2005年第2期100-112,共13页
Trichoderma/Hypocrea is a genus of soil-borne or wood-decaying fungi containing members important to mankind as producers of industrial enzymes and biocontrol agents against plant pathogens, but also as opportunistic ... Trichoderma/Hypocrea is a genus of soil-borne or wood-decaying fungi containing members important to mankind as producers of industrial enzymes and biocontrol agents against plant pathogens, but also as opportunistic pathogens of immunocompromised humans. Species identification, while essential in view of the controversial properties of taxa ofthis genus, has been problematic by traditional methods. Here we will present a critical survey of the various identification methods in use. In addition,we will present an update on the taxonomy and phylogeny of the 88 taxa (which occur as 14 holomorphs, 49 teleomorphs and 25 anamorphs in nature) of Trichoderma/Hypocrea that have been confirmed by a combination of morphological, physiological and genetic approaches. 展开更多
关键词 TrichodermalHypocrea GENUS Molecular taxonomy-phylogeny
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Reconstruction of the Medial Patellofemoral Ligament Using Hamstring Tendon Graft With Different Methods:a Biomechanical Study 被引量:1
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作者 Wei He Yu-ming Yang +2 位作者 Ming Liu Ai-yuan Wang Yu-jie Liu 《Chinese Medical Sciences Journal》 CAS CSCD 2013年第4期201-205,共5页
Objective To measure the tensile strength of the normal medial patellofemoral ligament(MPFL),and evaluate the biomechanics of different fixation methods of the hamstring tendon graft on the patella.Methods Eight fresh... Objective To measure the tensile strength of the normal medial patellofemoral ligament(MPFL),and evaluate the biomechanics of different fixation methods of the hamstring tendon graft on the patella.Methods Eight fresh cadaver knees were prepared by isolating the patella,leaving only the MPFL as its attachment to the medial condyle of femur.The MPFL was reconstructed by three different methods:four-suture fixation,anchors-single suture fixation,and anchors-double suture fixation.The tensile strength and the elongation of the normal MPFL and the tendon grafts were measured.Results The tensile strength of the four-suture fixation group(234.86±49.02 N)was stronger than that of the normal MPFL(146.91±25.30 N,P=0.0014)and the anchors-single suture group(159.17±49.07N,P=0.0077),while weaker than that of the anchors-double suture group(314.74±78.46 N,P=0.0052)Conclusions With regard to the tensile strength,the four-suture fixation method is reliable for clinical use.Compared with the anchor-suture method,the four-suture fixation method which has no specific implants is more economical,convenient and efficient. 展开更多
关键词 medial patellofemoral ligament BIOMECHANICS fixation method hamstring tendons
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Calculation of Ecological Footprint Based on Modified Method and Quantitative Analysis of Its Impact Factors——A Case Study of Shanghai 被引量:4
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作者 GAO Chengkang JIANG Dahe +1 位作者 WANG Dan YAN Jonathan 《Chinese Geographical Science》 SCIE CSCD 2006年第4期306-313,共8页
Ecological footprint (EF) has attracted much attention internationally as a potential indicator for sustainable development. In China, EF has also gained recognition in related fields and disciplines. Moreover, some... Ecological footprint (EF) has attracted much attention internationally as a potential indicator for sustainable development. In China, EF has also gained recognition in related fields and disciplines. Moreover, some scholars in these fields have proposed alternative methods to calculate EF and have made some progress. This paper, therefore, begins with the introduction and development of EF in China. However, the established methods of EF calculation hold some limitations, such as indicator variance and result abnormality. In order to resolve those problems, the authors make a further modification considering the demand of EF as a comprehensive indicator: 1) More accurate analysis has been done to divide EF into several parts: imported EF, exported EF, and producible EF, which is the solution to the problem of abnormality in original EF results and can explain abnormal phenomena reasonably. 2) Considering the actual situa- tion of Shanghai, emended equivalence factor is brought forward and a matrix is formed with equivalence factors. The measure can reduce the deviation between the fact and the results. 3) The calculation compares local yield with global average yield to analyze the effects of yields. And based on local yields in different years, the results are more accurate. Finally, the calculation method is applied to calculating EF of Shanghai from 1980 to 2003, and the subsequent detailed analysis is presented. Available data and results suggest a statistically significant correlation coefficient between EF and GDP, population density and urbaniTation level. Through analyzing the process of calculating EF and its results, it can be seen that EF, as a macro-indicator, can not exactly indicate whether development within a region can meet the re- quests of sustainable development, which can be explained by the fact that the result of EF is impacted greatly by sub- jective factors including national policy,available technology, population, etc. Nevertheless, EF can demonstrate, at least to some degree, the regional status in terms of resources and energy consumption, as well as developmental potential. The calculation of EF, therefore, deserves further research to achieve more far-reaching significance in application. 展开更多
关键词 ecological footprint quantitative analysis impact factors SHANGHAI
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Research Approaches in Applied Linguistics
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作者 梁晶 《International English Education Research》 2014年第10期114-116,共3页
Research in applied linguistics, like research in other fields, is usually carried out by two approaches: quantitative approach and qualitative approach. It is agreed "both approach are needed, since no one methodol... Research in applied linguistics, like research in other fields, is usually carried out by two approaches: quantitative approach and qualitative approach. It is agreed "both approach are needed, since no one methodology can answer all questions and provide insights on all issues". The two approaches follow different procedures and inevitably have respective advantages and drawbacks. Three general types of quantitative methods are experiments, quasi-experiments and surveys. Three general types of methods concerning qualitative approach used in linguistics are case study, action research and ethnographic research. Different types of research questions can be studied through various research methods. It is important to recognise the distinction between quantitative approach and qualitative approaches. It is up to the researcher to choose the specific approach in accordance with the suitability of the method for the particular research. It can be a single approach, or combination of the two, providing it allows maximal reliability and validity of the study. 展开更多
关键词 quantitative approach qualitative approach advantages LIMITATIONS
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Comprehensive Evaluation on Urban Sustainable Development of Harbin City in Northeast China 被引量:4
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作者 CAI Chunmiao SHANG Jincheng 《Chinese Geographical Science》 SCIE CSCD 2009年第2期144-150,共7页
It is an effective way in realizing urban coordinated and sustainable development to establish a series of in- dicators and to evaluate urban environmental and socioeconomic development. According to the characteristi... It is an effective way in realizing urban coordinated and sustainable development to establish a series of in- dicators and to evaluate urban environmental and socioeconomic development. According to the characteristics of Harbin City in Northeast China, an indicator system including five subsystems and 37 indicators was established for comprehensive evaluation on urban sustainable development. The development indexes of all urban subsystems and complex system were calculated quantitatively using the comprehensively integrated methods composed of Principle Component Analysis, Analytic Hierarchy Process and weighed index method, and then the comprehensive level of ur- ban sustainable development and the degree of urban interior coordination were analyzed. The results indicated that 1) the overall urban development presented an uptrend, however, the interior development was not well balanced from 1996 to 2006; 2) the development in each subsystem presented a strong fluctuation; and 3) the development in re- sources subsystem showed a downtrend. Based on those results, the suggestions of urban sustainable development were put forward at the end. 展开更多
关键词 sustainable development indicator system comprehensive evaluation Harbin City
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A New Bioassay Method for Evaluation Allelopathic Potential of Rice Germplasm 被引量:2
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作者 Yongliang Lu Hong Lu +3 位作者 Kilung Kim Yiding Sun Jian Fu Yiqing Guo 《Journal of Life Sciences》 2016年第3期128-133,共6页
Allelopathy was defined in 1996 by IAS (international allelopathy society) as any process involving secondary metabolites produced by plant, algae, bacteria and fungi that influences the growth and development of ag... Allelopathy was defined in 1996 by IAS (international allelopathy society) as any process involving secondary metabolites produced by plant, algae, bacteria and fungi that influences the growth and development of agricultural and biological systems. Rice allelopathy against weeds was reported since 1989, which offers an integrated weed management with substantially reduced herbicide usage. Application of allelopathic rice cultivars is thought a resources conservation and environmental friendly way of weed bio-control, and could promote the sustainable development of agriculture. Screening or evaluating the allelopathic potential rice variety is the first step. In this paper, a new bioassay method was set up by the allelopathic potential of 9 rice lines on the target weed barnyardgrass (Echinochloa crusgalli), and comparing with bioassay methods such as relay seeding in filter paper (RSF) and relay seeding in agar (RSA). The results indicated that three methods had a same tendency in evaluating the allelopathic potential of rice; there existed a significant difference among different bioassay methods, and an interaction between bioassay methods and rice lines. The method of root exudates (RE) with the highest value and a correlation efficiency of 0.98 was considered as ideal bioassay method for evaluation of allelopathic potential. 展开更多
关键词 RICE allelopathic potential bioassay methods comparison.
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A Novel Deep Learning Method for Application Identification in Wireless Network 被引量:8
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作者 Jie Ren Zulin Wang 《China Communications》 SCIE CSCD 2018年第10期73-83,共11页
In modern wireless communication network, the increased consumer demands for multi-type applications and high quality services have become a prominent trend, and put considerable pressure on the wireless network. In t... In modern wireless communication network, the increased consumer demands for multi-type applications and high quality services have become a prominent trend, and put considerable pressure on the wireless network. In that case, the Quality of Experience(Qo E) has received much attention and has become a key performance measurement for the application and service. In order to meet the users' expectations, the management of the resource is crucial in wireless network, especially the Qo E based resource allocation. One of the effective way for resource allocation management is accurate application identification. In this paper, we propose a novel deep learning based method for application identification. We first analyse the requirement of managing Qo E for wireless communication, and review the limitation of the traditional identification methods. After that, a deep learning based method is proposed for automatically extracting the features and identifying the type of application. The proposed method is evaluated by using the practical wireless traffic data, and the experiments verify the effectiveness of our method. 展开更多
关键词 quality of experience application identification protocol identification deeplearning feature extraction
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AN INVESTIGATION OF RETINEX ALGORITHMS FOR IMAGE ENHANCEMENT 被引量:9
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作者 Lei Ling Zhou Yinqing Li Jingwen 《Journal of Electronics(China)》 2007年第5期696-700,共5页
This letter introduces color constancy and Retinex theory for image enhancement.It clas- sifies Retinex algorithms into four categories and provides their principles and implementations in general.The experimental res... This letter introduces color constancy and Retinex theory for image enhancement.It clas- sifies Retinex algorithms into four categories and provides their principles and implementations in general.The experimental results of Frankle-McCann,MSR (Multi-Scale Retinex) and PNSD (Pro- jected Normalized Steepest Descent) Retinex algorithms are presented and compared.Moreover, variance and average gradient are proposed to evaluate the performance of the different algorithms. 展开更多
关键词 Color constancy RETINEX Frankle-McCann MSR (Multi-Scale Retinex) PNSD (Pro-jected Normalized Steepest Descent)
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A New Method of Identification on Edible Lycium Linn. Germplasm Resources——nrDNA ITS Sequencing 被引量:1
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作者 石志刚 安巍 +2 位作者 焦恩宁 赵建华 王亚军 《Agricultural Science & Technology》 CAS 2008年第2期58-59,105,共3页
[ Objective ] The study aimed to identify Lycium Linn. at molecular level. [ Method ] The nrDNA ITS sequence of 5 edible Lycium Linn. germplasm resources were investigated. [ Result ] The nrDNA ITS regions of five edi... [ Objective ] The study aimed to identify Lycium Linn. at molecular level. [ Method ] The nrDNA ITS sequence of 5 edible Lycium Linn. germplasm resources were investigated. [ Result ] The nrDNA ITS regions of five edible Lycium Liun. germplasm resources were sequenced. The whole sequences varied from 628 bp to 632 bp, with the average length of 630 bp. Total 79 variation sites were observed in the sequences, which accounts for 12. 5%. [ Conclusion] Sequence analysis based on nrDNA sequencing provides a new approach to identify edible Lycium Linn. germplasm resources. 展开更多
关键词 Lycium Linn. ITS sequence DNA sequencing IDENTIFICATION
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Analysis of volatile chemical components of Radix Paeoniae Rubra by gas chromatography-mass spectrometry and chemometric resolution 被引量:11
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作者 李晓如 兰正刚 梁逸曾 《Journal of Central South University of Technology》 2007年第1期57-61,共5页
The volatile chemical components of Radix Paeoniae Rubra (RPR) were analyzed by gas chromatography-mass spectrometry with the method of heuristic evolving latent projections and overall volume integration. The results... The volatile chemical components of Radix Paeoniae Rubra (RPR) were analyzed by gas chromatography-mass spectrometry with the method of heuristic evolving latent projections and overall volume integration. The results show that 38 volatile chemical components of RPR are determined, accounting for 95.21% of total contents of volatile chemical components of RPR. The main volatile chemical components of RPR are (Z, Z)-9,12-octadecadienoic acid, n-hexadecanoic acid, 2-hydroxy- benzaldehyde, 1-(2-hydroxy-4-methoxyphenyl)-ethanone, 6,6-dimethyl-bicyclo[3.1.1] heptane-2-methanol, 4,7-dimethyl-benzofuran, 4-(1-methylethenyl)-1-cyclohexene-1-carboxaldehyde, and cyclohexadecane. 展开更多
关键词 Radix Paeoniae Rubra volatile chemical components gas chromatography-mass spectrometry heuristic evolving latent projections
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Estimation of Acentric Factor of Organic Compounds with Corresponding States Group Contribution Method 被引量:3
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作者 衣守志 贾原媛 马沛生 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2005年第5期709-712,共4页
A new estimation method was proposed by combining the corresponding state principle with the group contribution method through introducing the concept of assumed-critical properties. Combining it with the Reidel equat... A new estimation method was proposed by combining the corresponding state principle with the group contribution method through introducing the concept of assumed-critical properties. Combining it with the Reidel equation, a new acentric factor correlation equation (CSGC-Reidel) was developed. Contribution values of 70 groups were obtained by correlating acentric factor data of 228 organic compounds of 14 type substances including saturated hydrocarbons, unsaturated hydrocarbons, cyclanes, aromatics, oxygen compounds, nitrogen compounds,halohydrocarbons, etc. The average error of acentric factor is 3.52% between the literature data and the predicated with the new estimation method. 展开更多
关键词 acentric factor estimation of properties corresponding state group contribution (CSGC) Edmister equation Reidel equation
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New self-calibration approach to space robots based on hand-eye vision 被引量:3
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作者 刘宇 刘宏 +1 位作者 倪风雷 徐文福 《Journal of Central South University》 SCIE EI CAS 2011年第4期1087-1096,共10页
To overcome the influence of on-orbit extreme temperature environment on the tool pose(position and orientation) accuracy of a space robot,a new self-calibration method based on a measurement camera(hand-eye vision) a... To overcome the influence of on-orbit extreme temperature environment on the tool pose(position and orientation) accuracy of a space robot,a new self-calibration method based on a measurement camera(hand-eye vision) attached to its end-effector was presented.Using the relative pose errors between the two adjacent calibration positions of the space robot,the cost function of the calibration was built,which was different from the conventional calibration method.The particle swarm optimization algorithm(PSO) was used to optimize the function to realize the geometrical parameter identification of the space robot.The above calibration method was carried out through self-calibration simulation of a six-DOF space robot whose end-effector was equipped with hand-eye vision.The results showed that after calibration there was a significant improvement of tool pose accuracy in a set of independent reference positions,which verified the feasibility of the method.At the same time,because it was unnecessary for this method to know the transformation matrix from the robot base to the calibration plate,it reduced the complexity of calibration model and shortened the error propagation chain,which benefited to improve the calibration accuracy. 展开更多
关键词 space robot SELF-CALIBRATION cost function hand-eye vision particle swarm optimization algorithm
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