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Quality Control of Tramadol in Kisangani: Development, Validation, and Application of a UV-Vis Spectroscopic Method 被引量:4
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作者 Marguerite Borive Amani Jérémie Mbinze Kindenge +4 位作者 Emile Tweni Baruti Elodie Nsasi Bakiantima Salomon Batina Agasa Philippe Hubert Roland Marini Djang’eing’a 《American Journal of Analytical Chemistry》 2021年第8期295-309,共15页
<strong>Context:</strong> Substandard and falsified medicines are circulating in low-income countries mostly without any control. We availed a simple and not expensive UV-Vis spectroscopic method to evalua... <strong>Context:</strong> Substandard and falsified medicines are circulating in low-income countries mostly without any control. We availed a simple and not expensive UV-Vis spectroscopic method to evaluate the quality of tramadol in Kisangani before and during the Covid-19 period. <strong>Methods:</strong> For the analytical quantitative method, an experimental design was applied to set up the optimal levels of the selected factors, namely, pH of dissolution medium, type of cuvette, and wavelength. Taking into account the capsule pharmaceutical formulation within 80 - 120 μg&middotmL<sup>-1</sup> concentration range, we analyzed 89 tramadol samples from pharmacies and hospitals of the six Kisangani municipalities. <strong>Results:</strong> pH showed a significant effect on absorbance, whereas quartz cuvette and wavelength did not. A typical 100 μg&middotmL<sup>-1</sup> tramadol solution gave an absorbance of 0.64 at 272 nm. Validation highlighted a matrix effect observed with a 6% bias. A correction factor of 0.9372 allowed to improve the accuracy profile, which were then totally included within the 10% acceptance limits. Quality control revealed that 25 samples out of 89 were not compliant in terms of manufacturing license, registration status in DRC and content as well. <strong>Conclusion:</strong> This study showed that the strengthening of analytical strategy in Kisangani is a need. 展开更多
关键词 TRAMADOL UV-Vis Spectroscopy method Development VALIDATION quality control
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Optimization of Quality Control Method and Ethanol Extraction Process of Psoralen and Bergapten in Ficus pandurata 被引量:1
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作者 Weiwen PENG Chang CHEN +2 位作者 Weibo DAI Yangcun LU Yingjing WANG 《Medicinal Plant》 CAS 2020年第3期51-54,59,共5页
[Objectives]To establish a qualitative identification and content determination method for psoralen and bergapten in the roots and leaves of Ficus pandurata,and the multi-indicator scoring method to optimize the ethan... [Objectives]To establish a qualitative identification and content determination method for psoralen and bergapten in the roots and leaves of Ficus pandurata,and the multi-indicator scoring method to optimize the ethanol extraction process for the effective parts of F.pandurata.[Methods]Qualitative identification was carried out by thin-layer chromatography(TLC)and content determination was made by high-performance liquid chromatography(HPLC);the content of psoralen and bergapten and extract yield were used as indicators,to investigate the effects of ethanol volume fraction,solid-to-liquid ratio,extraction time and extraction times on the ethanol extraction process of F.pandurata;multi-indicator scoring method was adopted,orthogonal test method was designed to optimize the extraction process,and verification test was performed.[Results]TLC chart of F.pandurata shows clear spots and good separation;the detected concentrations of psoralen and bergapten in the roots are in the range of 1.02-32.64μg/mL and shows a good linear relationship with the peak area(r=0.9997);these components have not been detected in the leaves,and the precision,RSD of stability and repeatability test is less than 2%;the average recovery rate was 99.8%-100.2%,and the RSD value is 1.12%-1.13%(n=6);the optimized extraction process is to use 50%ethanol as the extraction solvent,the solid-to-liquid ratio of 1∶10,reflux extraction of 3 times,and 1.5 h each time;the results of the three batches of verification tests show that the content of the two indicator components obtained is high,and the average value of the total amount is 0.34 mg/g(RSD=0.30%,n=3).[Conclusions]The established quality control method for F.pandurata is simple,easy,accurate and reproducible;the preferred extraction process is stable and feasible,suitable for the extraction and purification of coumarin effective parts in F.pandurata roots,so it is expected to provide references for further development of F.pandurata. 展开更多
关键词 Ficus pandurata Hance quality control Extraction process Orthogonal experiment Multi-indicator scoring method
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Study on Rear-end Real-time Data Quality Control Method of Regional Automatic Weather Station
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作者 WANG Chao-qiu 《Meteorological and Environmental Research》 CAS 2011年第9期6-8,12,共4页
[Objective] The aim was to study the rear-end real-time data quality control method of regional automatic weather station. [Method] The basic content and steps of rear-end real-time data quality control of regional au... [Objective] The aim was to study the rear-end real-time data quality control method of regional automatic weather station. [Method] The basic content and steps of rear-end real-time data quality control of regional automatic weather station were introduced. Each element was treated with systematic quality control procedure. The existence of rear-end real time data of regional meteorological station in Guangxi was expounded. Combining with relevant elements and linear changes, improvement based on traditional quality control method was made. By dint of evaluation and relevant check of element, the quality of temperature and pressure was controlled. [Result] The method was optimized based on traditional quality control method, and it narrowed the effectiveness of real-time data quality control. The quality check of hourly precipitation applied relevant check of hourly minimum temperature, vertical consistency check of radar data, which can effectively improve the accuracy and credibility of hourly precipitation quality control. [Conclusion] The method was on trial for one year in the quality control of real-time data in the regional automatic meteorological station in Guangxi and had gained good outcome. 展开更多
关键词 Regional automatic stations Real-time data quality control method research China
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Analytical Methods in Quality Control of Scientific Publications
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作者 Ilia Brondz 《American Journal of Analytical Chemistry》 2012年第6期443-447,共5页
Plagiarism, fake or even falsified presentation has become a major plague for scientific publications. This paper is a response to personal appeal by David JW Lane the Editor-in-Chief of Research and Reports in Biodiv... Plagiarism, fake or even falsified presentation has become a major plague for scientific publications. This paper is a response to personal appeal by David JW Lane the Editor-in-Chief of Research and Reports in Biodiversity Studies to support and promote the international author standards as developed by COPE for authors and editors-in-chief posted to me April 3rd 2012 (International standards for editors and authors http://www.dovepress.com/rrbscope.t9699812). As corresponding author for more than 100 scientific papers, dozens of scientific reviews, several chapters in scientific books, and author and editor of a book Historical Overview of Chromatography and Related Techniques in Analysis of Antimalarial Drug Primaquine, and as a reviewer of Journal of Chromatography, Journal of Chromatography A, Journal of Chromatography B: Biomedical Sciences and Applications, Lipids, Journal of General Microbiology, Journal of Clinical Microbiology, Journal of Microbiological Methods, Oral Microbiology and Immunology, Analytica Chimica Acta, Mycological Research and Journal of Pharmaceutical and Biomedical Analysis, and member of editorial board of Electronic Components and Systems, American Journal of Analytical Chemistry, ISRN Chromatography and Open Journal of Clinical Diagnostics I was adhered to a new ethical and moral standards in scientific publications. The presented paper is an example of use the analytical methods in visualizing of plagiarism and falsification in the published scientific literature. It is obvious that some of scientific publications need careful quality control. Some papers should have been rejected but were not. These papers clearly pollute the field of scientific information. It is not always easy to demonstrate inappropriate presentation even when many supporting facts are available. The facts should be obvious;there should be no hesitation about the quality or value of a paper presented for consideration to be published. Plagiarism is most common and harmful phenomenon in scientific publications. The plagiarism is based on an original discovery or reproduction of the results from the other authors. The analytical methods used in the quality control of the data can disclose plagiarism. An example is the publication under scrutiny “Applications of GC-EI-MS for the Identification of Positional Isomer in Primaquine, an Antimalarial Drug” by Dongre et al. (2005) Journal of Pharmaceutical and Biomedical Analysis 39, No. 1-2, 111-116. 展开更多
关键词 ANALYTICAL methodS in quality control 13C NMR SPECTROSCOPY PRIMAQUINE Quinocide
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The Theory and Methods Research on Ecological Quality Control of Enterprises
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作者 Han Furong 《China Standardization》 2005年第2期21-26,共6页
So far, most theories of economics and management are under the same premisethat the natural resources are never exhausted and regenerated repeatedly. The magic of technologybrought by industrial revolution endowed hu... So far, most theories of economics and management are under the same premisethat the natural resources are never exhausted and regenerated repeatedly. The magic of technologybrought by industrial revolution endowed human with power that they can do anything they want. Italso turns natural resources into industrial energy and enhances the development of human societyand civilization. Human uses direct comparison of input and output and the satisfaction degree ofdemands to measure the production activities, the economic benefit and management performance,regardless of the change of ecology that serves as the natural resources. However, since theecological environment has been changing worse recently and natural disaster happened frequentlyhuman's dream of conquering the nature has been broken. The nature implements reprisal against humanagain and again, and human is faced with the development limit because of the environmentalrestriction. 展开更多
关键词 The Theory and methods Research on Ecological quality control of Enterprises
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Quality Control on Crimping of Large Diameter Welding Pipe 被引量:3
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作者 FAN Lifeng GAO Ying +1 位作者 LI Qiang XU Hongshen 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2012年第6期1264-1273,共10页
Crimping is used in production of large diameter submerged-arc welding pipes. Many researches are focused on crimping in certain manufacturing mode of welding pipe. The application scopes of research achievements beco... Crimping is used in production of large diameter submerged-arc welding pipes. Many researches are focused on crimping in certain manufacturing mode of welding pipe. The application scopes of research achievements become limited due to lack of uniformity in theoretical analysis. In order to propose a crimping prediction method in order to control forming quality, the theory model of crimping based on elastic-plastic mechanics is established. The main technical parameters are determined by theoretical analysis, including length of crimping, base radius of punch, terminal angle of punch, base radius of die, terminal angle of die and horizontal distance between punch and die. In addition, a method used to evaluate the forming quality is presented, which investigates the bending angle after springback, forming force, straight edge length and equivalent radius of curvature. In order to investigate the effects of technical parameters on forming quality, a two-dimensional finite element model is established by finite element software ABAQUS. The finite element model is verified in that its shapes error is less than 5% by comparable experiments, which shows that their geometric precision meets demand. The crimping characteristics is obtained, such as the distribution of stress and strain and the changes of forming force, and the relation curves of technical parameters on forming quality are given by simulation analysis. The sensitivity analysis indicates that the effects of length of crimping, technical parameters of punch on forming quality are significant. In particular, the data from simulation analysis are regressed by response surface method (RSM) to establish prediction model. The feasible technical parameters are obtained from the prediction model. This method presented provides a new thought used to design technical parameters of crimping forming and makes a basis for improving crimping forming quality. 展开更多
关键词 welding pipe crimping forming forming quality control finite element analysis(FEA) response surface method(RSM)
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VPLS Based Quality and Cost Control for Tennessee Eastman Process 被引量:1
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作者 宋凯 王海清 李平 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2005年第1期62-67,共6页
Product quality and operation cost control obtain increasing emphases in modern chemical system engineering. To improve the fault detection power of the partial least square (PLS) method for quality control, a new QRP... Product quality and operation cost control obtain increasing emphases in modern chemical system engineering. To improve the fault detection power of the partial least square (PLS) method for quality control, a new QRPV statistic is proposed in terms of the VP (variable importance in projection) indices of monitored process variables, which is significantly advanced over and different from the conventional Q statistic. QRPV is calculated only by the residuals of the remarkable process variables (RPVs). Therefore, it is the dominant relation between quality and RPV not all process variables (as in the case of the conventional PLS) that is monitored by this new VP-PLS (VPLS) method. The combination of QRPV and T2 statistics is applied to the quality and cost control of the Tennessee Eastman (TE) process, and weak faults can be detected as quickly as possible. Consequently, the product quality of TE process is guaranteed and operation costs are reduced. 展开更多
关键词 partial least squares method Tennessee Eastman process statistical quality control cost control on-line monitoring
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Dynamic estimation and reliability control of quality assurance for bored piles
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作者 赵文艺 徐志军 +1 位作者 郑俊杰 边晓亚 《Journal of Central South University》 SCIE EI CAS 2014年第3期1148-1157,共10页
A systematic method was proposed to estimate the occurrence probability of defective piles(OPDP) from a site according to quality assurance inspection. The OPDP was firstly suggested as the criterion to weight the per... A systematic method was proposed to estimate the occurrence probability of defective piles(OPDP) from a site according to quality assurance inspection. The OPDP was firstly suggested as the criterion to weight the performance of a pile foundation. Its prior distribution and updating distribution were deduced to follow Beta distributions. To calibrate the OPDP, a dynamic estimation model was established according to the relationships between prior mean and variance and updating mean and variance. Finally, a reliability-control method dealing with uncertainties arising from quality assurance inspection was formalized to judge whether all the bored piles from a site can be accepted. It is exemplified that the OPDP can be substantially improved when more definite prior information and sampling formation become available. For the example studied herein, the Bayesian estimator of updating variance for OPDP is reduced from 0.0037 to 0.0014 for the first inspection, from 0.0014 to 0.0009 for the second inspection, and with less uncertainty by incorporating experience information. 展开更多
关键词 bored piles quality assurance inspection reliability control occurrence probability Bayesian method
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Optimal control of a quality supervision profit model for the electronic intermediary
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作者 XU Ying-tao ZHANG Ying LV Zhen-hong 《Applied Mathematics(A Journal of Chinese Universities)》 SCIE CSCD 2021年第2期159-171,共13页
Online customers execute transactions without inspecting products could expect to encounter risks of receiving products with unsatisfactory qualities,especially in food trans-actions.Thus quality supervision plays a k... Online customers execute transactions without inspecting products could expect to encounter risks of receiving products with unsatisfactory qualities,especially in food trans-actions.Thus quality supervision plays a key role in the establishment of trust as well as in the management of risk between online customers and sellers.Most papers in this field are in qualitative nature.In this paper,a quality supervision profit(QSP)model is formulated as a discrete-time optimal control problem.It is a quantitative approach,and it broadens the scope.of current research in the area.The quality efort level of online sellers(QELa)and the quality supervision level of the electronic intermediary(QSLm)are considered together with their cor-responding profit in the proposed model.The aim is to optimize an overall profit.A case study arising from Suichang's food traceability system(FTS)of farm produce online transaction is carried out in details.The results reveal that QELs,QSLm and the profit distribution coeffi-cient have a strong influence upon the profits of both sides.Finally,some concluding remarks,including potential further research topics,are given. 展开更多
关键词 electronic intermediary quality supervision discrete-time optimal control method
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HPLC Profiling for Quality Control of Secondary Metabolites of Aqueous and Hydroethanolic Extract of Gardenia aqualla Stapf &Hutch
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作者 Claude Bérenger Ngantchouko Ngalemo Jean Kisito Kouame +5 位作者 Gisele Laurel Tchiengang Tchoua Blondin Gatien Tsawo Patrick Yamen Mbopi Théophille Dimo Christophe N’cho Amin François Nicaise Bony 《American Journal of Analytical Chemistry》 CAS 2023年第1期1-11,共11页
WHO strategy on traditional medicine is based on security and quality of phytomedicine. Commonly adulterated affecting mostly metabolic and sexual dysfunction drugs. Control quality of those phytomedicines requires de... WHO strategy on traditional medicine is based on security and quality of phytomedicine. Commonly adulterated affecting mostly metabolic and sexual dysfunction drugs. Control quality of those phytomedicines requires development of strategy and techniques applicable to them. Among the techniques, Reverse Phase Liquid Chromatography is the most used and has been developed in these studies to assess a protocol to characterize Gardenia aqualla leaves extract. The method consists in determining chromatographic conditions using organic and pH gradient models based on water and acetonitrile combined with pH modifiers made up of formic acid (AF) and ammonium hydroxide (NH<sub>3</sub>). Results show that extracts contain mainly acidic compounds quickly eluted by NH<sub>3</sub> and more retained by AF. Optimal pH range for separation is 3 - 7 corresponding to 1.59 mM of NH<sub>3</sub> and 6.55 mM of AF. In these conditions, elution of many polar compounds could be effective using a C18 based-deactivated column in a short period of time. 展开更多
关键词 Gardenia aqualla Extracts quality control method Development Reverse Phase Liquid Chromatography
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Chinese herbal medicine Xinfeng Capsule in treatment of rheumatoid arthritis:study protocol of a multicenter randomized controlled trial 被引量:9
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作者 Jian Liu Chuan-bing Huang +5 位作者 Yuan Wang Gui-qin Xu Yuan-yuan Cheng Yun-xia Feng Lei Liu Ya-jun Qi 《Journal of Integrative Medicine》 SCIE CAS CSCD 2013年第6期428-434,共7页
BACKGROUND: Rheumatoid arthritis (RA), as a common systemic inflammatory autoimmune disease, affects approximately 1 in 100 individuals. Effective treatment for RA is not yet available because current research does... BACKGROUND: Rheumatoid arthritis (RA), as a common systemic inflammatory autoimmune disease, affects approximately 1 in 100 individuals. Effective treatment for RA is not yet available because current research does not have a clear understanding of the etiology and pathogenesis of RA. Xinfeng Capsule, a patent Chinese herbal medicine, has been used in the treatment of RA in recent years. Despite its reported clinical efficacy, there are no large-sample, multicenter, randomized trials that support the use of Xinfeng Capsule for RA. Therefore, we designed a randomized, double-blind, multicenter, placebo-controlled trial to assess the efficacy and safety of Xinfeng Capsule in the treatment of RA. METHODS AND DESIGN: This is a 12-week, randomized, placebo-controlled, double-blind, multicenter trial on the treatment of RA. The participants will be randomly assigned to the experimental group and the control group at a ratio of 1:1. Participants in the experimental group will receive Xinfeng Capsule and a pharmaceutical placebo (imitation leflunomide). The control group will receive leflunomide and an herbal placebo (imitation Xinfeng Capsule). The American College of Rheumatology (ACR) Criteria for RA will be used to measure the efficacy of the Xinfeng Capsule. The primary outcome measure will be the percentage of study participants who achieve an ACR 20% response rate (ACR20), which will be measured every 4 weeks after randomization. Secondary outcomes will include the ACR50 and ACR70 responses, the side effects of the medications, the Disease Activity Score 28, RA biomarkers, quality of life, and X-rays of the hands and wrists. The first four of the secondary outcomes will be measured every 4 weeks and the others will be measured at baseline and after 12 weeks of treatment. DISCUSSION: The result of this trial will help to evaluate whether Xinfeng Capsule is effective and safe in the treatment of RA. TRIAL REGISTRATION: This trial has been registered in ClinicalTrials.gov. The identifier is N CT01774877. 展开更多
关键词 Xinfeng Capsule rheumatoid arthritis double-blind method PLACEBOS ACRcriteria quality of life randomized controlled trials clinical protocols
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Chromatographic fingerprint analysis of Fructus Aurantii Immaturus by HPLC-DAD and chemometric methods 被引量:4
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作者 徐小娜 蒋军辉 +3 位作者 梁逸曾 李晓如 易伦朝 成金乐 《Journal of Central South University》 SCIE EI CAS 2011年第2期353-360,共8页
An efficient method for quality control of Fructus Aurantii Immaturus (FAI),a famous traditional Chinese medicine (TCM) was established. A simple and reliable high-performance liquid chromatography-photodiode array de... An efficient method for quality control of Fructus Aurantii Immaturus (FAI),a famous traditional Chinese medicine (TCM) was established. A simple and reliable high-performance liquid chromatography-photodiode array detector (HPLC-DAD) procedure coupled with chemometric methods was developed for fingerprint analysis,qualitative analysis and quantitative determination of this herb. In qualitative and quantitative analyses,heuristic evolving latent projection (HELP) method was employed to resolve the overlapping peaks of the tested samples. Two bioactive components,namely hesperidin and naringin,are confirmed and determined,together with four flavonoids compounds tentatively identified including two new ones. From fingerprint analysis,the fingerprint data were processed with correlation coefficients for quantitative expression of their similarity and dissimilarity. The developed method based on an integration of chromatographic fingerprint and quantitative analysis is scientific,and the obtained results can be applied to the quality control of herb medicine. 展开更多
关键词 FINGERPRINT quality control Fructus Aurantii Immaturus high-performance liquid chromatography heuristic evolvinglatent projection method HESPERIDIN NARINGIN
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Application of imputation methods to genomic selection in Chinese Holstein cattle 被引量:2
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作者 Ziqing Weng Zhe Zhang +4 位作者 Xiangdong Ding Weixuan Fu Peipei Ma Chonglong Wang Qin Zhang 《Journal of Animal Science and Biotechnology》 SCIE 2012年第1期16-20,共5页
关键词 Chinese Holstein Cows dairy cattle genomic selection imputation methods quality control SNP
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A new PAT application: Optimization of processing methods for honeysuckle flower (Lonicerae Japonicae Flos) and wild honeysuckle flower (Lonicerae Flos) 被引量:1
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作者 Jiangbo Hao Zhisheng Wu +2 位作者 Weidong Li Zhongshuang Zhang Jinrui Gu 《Journal of Traditional Chinese Medical Sciences》 2018年第2期199-205,共7页
Objective:A novel processing analytical framework of Chinese Material Medica (CMM) includes breeding process analysis,planting process analysis,producing process analysis and manufacture process analysis.In order to s... Objective:A novel processing analytical framework of Chinese Material Medica (CMM) includes breeding process analysis,planting process analysis,producing process analysis and manufacture process analysis.In order to study this framework,we used quality control of honeysuckle flower (Lonicerae japonicae Flos) including diploid and tetraploid Lonicera japonica,and wild honeysuckle flower (Lonicerae Flos) including Lonicerae hypoglauca,Lonicerae confusa,Lonicerae fulvotomentosa and Lonicerae macranthoides as an example.Methods:A total of 360 samples were analyzed from three variables including species,growing areas,and optimization of processing methods.For quantitative analysis,chlorogenic acid (CA),isochlorogenic acid A (3,5-DCA),and isochlorogenic acid C (4,5-DCA) were measured with high performance liquid chromatography (HPLC).Results:The three organic acids contents are higher in wild honeysuckle flower than honeysuckle flower;L.japonica (tetraploid) is higher than L.japonica (diploid).Modern processing methods (kill-enzyme torrefaction and fixing machine drying) are popular in growing areas and are superior to traditional methods (sun and shade drying).Conclusions:Novel process analysis concepts in processing analytical technology (PAT) enriched the Chinese MateHal Medica contents. 展开更多
关键词 HONEYSUCKLE FLOWER WILD HONEYSUCKLE FLOWER PROCESSING ANALYTICAL technology quality control PROCESSING method
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Procedure Design to Fulfill Quality Management System
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作者 LIU Shu-qing (Xi’an University of Technology, Xi’an 710048, China) 《厦门大学学报(自然科学版)》 CAS CSCD 北大核心 2002年第S1期277-278,共2页
With the application of the principle of PDCA, and dr awing on the experience of the process methods of the ISO9000 and the system met hods of management, the author analyses the basic requirement to fulfill quality m... With the application of the principle of PDCA, and dr awing on the experience of the process methods of the ISO9000 and the system met hods of management, the author analyses the basic requirement to fulfill quality management system in enterprises. Then the author inquires into the procedure t o establish the efficiency quality management system. Finally four stages (plan, do, check, action) and eight steps (decision, plan, analyze, design, do, check, improve, fulfill) are put forward to fulfill quality management system. 展开更多
关键词 quality management system process methods fulfi ll procedure improve instantly
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Numerical Prediction and Analysis of Hydraulic Characteristics of Waterfall Scene for Application to Design Control
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作者 Chao Wang Sherong Zhang +3 位作者 Yun Li Guojin Zhu Bohui Pang Xiaofang Zheng 《Transactions of Tianjin University》 EI CAS 2017年第3期277-288,共12页
The hydraulic characteristics of artificial waterfalls constitute an important research area for both academia and industry. As yet, the hydraulic parameters used in the hydraulic design of landscape waterfalls are no... The hydraulic characteristics of artificial waterfalls constitute an important research area for both academia and industry. As yet, the hydraulic parameters used in the hydraulic design of landscape waterfalls are not well understood for use in qualitative and quantitative analyses. Due to their complicated shapes and appearances, it remains a challenging problem to design or simulate realistic waterfall scenes. In this paper, we present a hybrid model and an efficient numerical method for simulating the hydraulic characteristics of waterfalls and investigate the critical flow in waterfall design and the adherent flow phenomenon. We fit empirical equations to predict the size and shape of different waterfall flow patterns to provide a basis for the design and construction of waterscapes in the real world. We then apply our work to an artificial waterfall in Kraal Jiang River and the results demonstrate that our model achieves desirable control qualities and good agreement in a real-world application. © 2017, Tianjin University and Springer-Verlag Berlin Heidelberg. 展开更多
关键词 BUOYANCY Computer simulation Numerical methods quality control
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Method of effective evaluation for examination of chloride ion in concrete
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作者 SUNGWen-pei CHENKuen-suan LINHsue-chun 《Journal of Zhejiang University-Science A(Applied Physics & Engineering)》 SCIE EI CAS CSCD 2005年第3期159-165,共7页
The chloride ion contained in reinforced concrete seriously corrodes the steel surface and damages concrete, resulting in inferior reinforced concrete that strength seriously compromises the entire structure’s safety... The chloride ion contained in reinforced concrete seriously corrodes the steel surface and damages concrete, resulting in inferior reinforced concrete that strength seriously compromises the entire structure’s safety. Consequently, the examination of chloride ions contained in reinforced concrete becomes an important part of a complete quality control procedure. To effectively check the concentration of chloride ions in concrete, the evaluation process should be accurate and precise. Laboratory data ob- tained using existing evaluation methods for the examination of chloride ion are not sufficiently objective to yield reliable results with accuracy and consistency for each sample. An evaluation algorithm with capability to define indices of precision degree (Ep) and accuracy degree (Ea) is presented in this paper. The authors established a statistically reliable index of unbiased estimators and equations to critically examine the laboratory methods’ precision, accuracy degrees and application value for measuring chlorine ion concentration in reinforced concrete. 展开更多
关键词 Concrete quality control Multi-laboratory Test error Accuracy degree Precision degree Natural estimator Acceptance testing Examination methods Evaluation criteria
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Audit of the Physico-Chemical Quality of Amoxicillin Based Drugs Marketed in Senegal
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作者 Coulibaly Dalané Bernadette Sow Fatoumata Tata +7 位作者 Naco Mohamed El Béchir N’Diaye Mahamar Toure Hamadoun Abba Mariko Madani Dackouo Blaise Diouf Diéry Koumare Benoit Yaranga Sarr Serigne Omar 《American Journal of Analytical Chemistry》 2023年第9期351-361,共11页
Non-compliant antibiotics pose problems of therapeutic efficacy at the level of the individual, but also a serious public health problem. The objective of our study was to evaluate the quality of generic amoxicillin (... Non-compliant antibiotics pose problems of therapeutic efficacy at the level of the individual, but also a serious public health problem. The objective of our study was to evaluate the quality of generic amoxicillin (42 samples) by analytical methods in Dakar/Senegal. At 100% visual inspection of compliance;100% compliance uniformity test;at the dissolution test all > 80% (86.8% to 108.8%). The presence of amoxicillin with the following contents: Tablets (95.2% to 104.1%);Capsules (91.5% to 113.9%) and Suspensions drinkable (96.9% - 118.7%). All the samples in our study are 100% compliant according to the European and American pharmacopoeias (90% - 120%). Other studies should therefore be oriented in the direction of stability as well as the dosage of degradation products. 展开更多
关键词 quality control AMOXICILLIN Analytical methods
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Internal Control and Internal Audit in the Function of Supervising the Operations of Companies
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作者 Zoran Todorović Božo Vukoja 《Management Studies》 2020年第4期325-332,共8页
The management of a modern company is faced with the need to make business decisions regarding the achievement of business goals.Increased interest in establishing internal control is affected by the presence increase... The management of a modern company is faced with the need to make business decisions regarding the achievement of business goals.Increased interest in establishing internal control is affected by the presence increased corruption and the erosion of business morality.For internal controls,everyone is interested,from external auditors to management,board of directors,shareholders of large public companies and the state.With the constant growth of the company,the decentralization of business has been compounded by the management process.Therefore,in addition to internal control,internal audit is required.The company’s management cannot deal with oversight because it has to deal with strategic issues.This is where internal audit is performed as an expert service.The results of the conducted empirical research showed that the stages of development of internal control in enterprises in Montenegro do not correspond with the achieved degree of development of this profession in the countries of the developed market economy. 展开更多
关键词 internal control internal audit business quality testing methods
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基于RPC的光储接入牵引供电系统协调控制方法 被引量:2
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作者 陈维荣 王小雨 +4 位作者 韩莹 臧治 李奇 沈文杰 许程鹏 《西南交通大学学报》 EI CSCD 北大核心 2024年第1期1-10,共10页
为将光伏发电接入牵引供电系统进行有效利用,同时兼顾牵引供电系统电能质量改善及列车再生制动能量回收利用,提出了一种基于铁路功率调节器的光储系统接入牵引供电系统的协调控制方法.首先,搭建基于铁路功率调节器的光储系统接入牵引供... 为将光伏发电接入牵引供电系统进行有效利用,同时兼顾牵引供电系统电能质量改善及列车再生制动能量回收利用,提出了一种基于铁路功率调节器的光储系统接入牵引供电系统的协调控制方法.首先,搭建基于铁路功率调节器的光储系统接入牵引供电拓扑结构,并对其电能质量补偿机理进行理论分析;在此基础上,充分考虑光储系统的运行条件以及列车牵引、制动、空载或惰行工况,提出光储系统接入牵引供电的联合协调控制方法,实现了“光+储+荷”三者间的协调控制、牵引供电系统负序的动态补偿以及谐波的有效抑制;在RT-Lab实时仿真系统中建立了基于铁路功率调节器的光伏接入牵引供电系统仿真模型,并结合实际光照和牵引工况数据验证本文所提出的系统结构以及协调控制方法的有效性.结果表明:本文所提出的系统结构以及协调控制方法能够实现牵引供电系统中光储系统的有效接入,再生制动能量回收率提升至86.7%,功率因数提升6.4%,对谐波特别是高次谐波含有率有较大改善,满足光伏电能高效消纳及综合利用、电能质量动态综合补偿、再生制动能量回收多重需求. 展开更多
关键词 铁路功率调节器 光储发电系统 牵引供电系统 协调控制方法 电能质量 电能分配
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