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Geographical origin identification of winter jujube(Ziziphus jujuba Dongzao')by using multi-element fingerprinting with chemometrics
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作者 Xiabing Kong Qiusheng Chen +8 位作者 Min Xu Yihui Liu Xiaoming Li Lingxi Han Qiang Zhang Haoliang Wan Lu Liu Xubo Zhao Jiyun Nie 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2024年第5期1749-1762,共14页
Winter jujube(Ziziphus jujuba'Dongzao')is greatly appreciated by consumers for its excellent quality,but brand infringement frequently occurs in the market.Here,we first determined a total of 38 elements in 16... Winter jujube(Ziziphus jujuba'Dongzao')is greatly appreciated by consumers for its excellent quality,but brand infringement frequently occurs in the market.Here,we first determined a total of 38 elements in 167 winter jujube samples from the main winter jujube producing areas of China by inductively coupled plasma mass spectrometer(ICP-MS).As a result,16 elements(Mg,K,Mn,Cu,Zn,Mo,Ba,Be,As,Se,Cd,Sb,Ce,Er,Tl,and Pb)exhibited significant differences in samples from different producing areas.Supervised linear discriminant analysis(LDA)and orthogonal projection to latent structures discriminant analysis(OPLS-DA)showed better performance in identifying the origin of samples than unsupervised principal component analysis(PCA).LDA and OPLS-DA had a mean identification accuracy of 87.84 and 94.64%in the testing set,respectively.By using the multilayer perceptron(MLP)and C5.0,the prediction accuracy of the models could reach 96.36 and 91.06%,respectively.Based on the above four chemometric methods,Cd,Tl,Mo and Se were selected as the main variables and principal markers for the origin identification of winter jujube.Overall,this study demonstrates that it is practical and precise to identify the origin of winter jujube through multi-element fingerprint analysis with chemometrics,and may also provide reference for establishing the origin traceability system of other fruits. 展开更多
关键词 winter jujube multi-element fingerprint analysis CHEMOMETRICS origin traceability
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Simultaneous thermal and contraction/expansion curves analysis for solidification control of cast irons 被引量:3
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作者 Iulian Riposan Stelian Stan +4 位作者 Mihai Chisamera Loredana Neacsu Ana Maria Cojocaru Eduard Stefan Iuliana Stan 《China Foundry》 SCIE 2020年第2期96-110,共15页
The first part of the paper summarizes the performance of two mould devices,illustrating by representative shrinkage tendency results in ductile cast iron as affected by mould rigidity(green and furan resin sand mould... The first part of the paper summarizes the performance of two mould devices,illustrating by representative shrinkage tendency results in ductile cast iron as affected by mould rigidity(green and furan resin sand moulds)and inoculant type(FeSi-based alloys).Less rigid green sand moulds encourage the formation of contraction defects,not only because of the high initial expansion values(ε(di))(max),but also because of the increased solidification undercooling.A high inoculation efficiency means not only lowering the carbides formation sensitivity and increasing the nodule count,but also a prolonged graphitization through to the end of the eutectic freezing,as observed by the high population of small late forming nodules,which leads to minimizing the tendency for shrinkage.The second part of the paper illustrates an application of this equipment to commercial foundry use.It conducts thermal analysis and volume change measurements in a single ceramic cup with cast iron quality as a variable.La-bearing FeSi inoculant appears to be more effective than RE(Rare Earth)-FeSi alloy in FeSiMgCa treated irons(no RE),in terms of reducing eutectic undercooling and(ε(di))(max),favourable for lower sensitivity to shrinkage formation.Experiments also compared solidification patterns for white[WI],grey[GI]and ductile[DI]irons,to correlate the most important events between the cooling curves and contraction curves,to evaluate the sensitivity to shrinkage formation.All of the irons have similar values for initial expansion up to the start of eutectic freezing,but,after that,the graphite formation promotes expansion(more than 5 times for nodular graphite),resulting in a difference in maximum expansion(2 times higher for DI).The graphitic expansion has two contrary effects.Increased graphitic expansion(force)leads to a higher shrinkage sensitivity during the first part of the eutectic reaction,but also to a decrease of shrinkage at the end of solidification,due to forcing the last liquid iron to occupy the previous formed cavities.Consequently,strong graphitization process promotion at the end of solidification favours the castings'soundness. 展开更多
关键词 white grey and DUCTILE castiron solidification UNDERCOOLING structure simultaneous THERMAL and CONTRACTION analysis graphite graphitic
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Simultaneous Spectrophotometric Determination of Four Components including Acetaminophen by Taget Factor Analysis
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作者 张立庆 《Journal of Wuhan University of Technology(Materials Science)》 SCIE EI CAS 2007年第3期569-571,共3页
UV Spectrophotometric Target Factor Analysis (TFA) was used for the simultaneous determination of four components (acetaminophen, guuaifenesin, caffeine, Chlorphenamine maleate) in cough syrup. The computer Frogra... UV Spectrophotometric Target Factor Analysis (TFA) was used for the simultaneous determination of four components (acetaminophen, guuaifenesin, caffeine, Chlorphenamine maleate) in cough syrup. The computer Frogram of TFA is based on VC++ language. The difficulty of overlapping of absorption spectra of four compounds was overcome by this procedure. The experimental results show that the average recovery of each component is all in the range from 98.9% to 106.8% and each component obtains satisfactory results without any pre-separation. 展开更多
关键词 ACETAMINOPHEN taget factor analysis SPECTROPHOTOMETRY four-component simultaneous determination
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Exploratory Data Analysis Applied in Mapping Multi-element Soil Geochemical Anomalies for Drill Target Definition:A Case Study from the Unpha Layered Non-magmatic Hydrothermal Pb-Zn Deposit,DPR Korea
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作者 JANG Gwang-Hyok WON Hyon-Chol +1 位作者 HWANG Bo-Hyon CHOI Chol-Man 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2021年第4期1357-1365,共9页
A factor analysis was applied to soil geochemical data to define anomalies related to buried Pb-Zn mineralization.A favorable main factor with a strong association of the elements Zn,Cu and Pb,related to mineralizatio... A factor analysis was applied to soil geochemical data to define anomalies related to buried Pb-Zn mineralization.A favorable main factor with a strong association of the elements Zn,Cu and Pb,related to mineralization,was selected for interpretation.The median+2 MAD(median absolute deviation)method of exploratory data analysis(EDA)and C-A(concentration-area)fractal modeling were then applied to the Mahalanobis distance,as defined by Zn,Cu and Pb from the factor analysis to set the thresholds for defining multi-element anomalies.As a result,the median+2 MAD method more successfully identified the Pb-Zn mineralization than the C-A fractal model.The soil anomaly identified by the median+2 MAD method on the Mahalanobis distances defined by three principal elements(Zn,Cu and Pb)rather than thirteen elements(Co,Zn,Cu,V,Mo,Ni,Cr,Mn,Pb,Ba,Sr,Zr and Ti)was the more favorable reflection of the ore body.The identified soil geochemical anomalies were compared with the in situ economic Pb-Zn ore bodies for validation.The results showed that the median+2 MAD approach is capable of mapping both strong and weak geochemical anomalies related to buried Pb-Zn mineralization,which is therefore useful at the reconnaissance drilling stage. 展开更多
关键词 factor analysis exploratory data analysis Mahalanobis distance multi-element Unpha
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Analysis of Difficulties in Simultaneous Interpreting(SI) from a Psycho-linguistic Perspective
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作者 刘安琪 《海外英语》 2017年第21期146-148,共3页
Nowadays,simultaneous interpreting(SI) plays a prominent role in global communications,especially for important international affairs.This kind of interpretation delivers information in an instantaneous way without wa... Nowadays,simultaneous interpreting(SI) plays a prominent role in global communications,especially for important international affairs.This kind of interpretation delivers information in an instantaneous way without wasting extra time for language processing.Performing well in SI requires long-time training and abundant experience.Making a comprehensive categorization and analysis on the difficulties in SI on the basis of psycho-linguistic theories are the key points.Due to the distinctive features of these difficulties,corresponding suggestions will be offered to improve the efficiency in SI training and to level up the performance of SI interpreters. 展开更多
关键词 simultaneous Interpreting(SI) difficulty analysis SI training psycho-linguistics
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Meta-analysis of efficacy and safety of concurrent or staged bilateral total knee arthroplasty
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作者 ALIMUJIANG∙Yusufu ABUDUWUPUER∙Haibier +2 位作者 WANG Ji-rong LI Wei RAN Jian 《Journal of Hainan Medical University》 CAS 2023年第14期58-67,共10页
Objective: To study the safety and efficacy of concurrent bilateral total knee arthroplasty orstaged bilateral total knee replacement using meta-analysis. Methods: The databases of ChinaWanfang, CNKI, PubMed, Cochrane... Objective: To study the safety and efficacy of concurrent bilateral total knee arthroplasty orstaged bilateral total knee replacement using meta-analysis. Methods: The databases of ChinaWanfang, CNKI, PubMed, Cochrane Library, and Web of Science were searched conducted formeta-analysis of the extracted data using Review Manager 5.3 software. Results: ①A total of 18retrospective cohort studies were included, 72 831 patients in the same period group and 103595 patients in the staging group. ②The results of meta showed that in the staging group, theincidence of postoperative cardiac complications[OR= 1.21, 95%CI=(1.10~1.34), P<0.000 1] ,neurological complications[OR=1.67, 95%CI=(1.29~2.16), P<0.000 1], deep vein thrombosis[OR=1.38, 95%CI(1.27~1.50), P<0.000 01], mortality[OR=2.18, 95%CI=(1.67~2.84),P<0.000 01] and perioperative blood loss [OR=246.75, 95%CI=(233.30~260.20)] were lessthan those in the same period group (P<0.000 01);The postoperative deep infection rate in thesame period group [OR=0.61, 95%CI=(0.52~0.71), P<0.000 01] was lower than that in thestaging group;The postoperative superficial infection rate [OR=0.96, 95%CI=(0.66~1.40)],revision rate of joint replacement [OR= 1.04, 95%CI=( 0.96~1.12)], HSS score [OR=0.10,95%CI=(-0.61~0.80), P=0.79] and knee joint activity score [OR=-0.23, 95%CI=(-1.25~0.78)]were not statistically significant between the two groups(P>0.05).Conclusion: Stagingbilateral total knee replacement can more effectively reduce the incidence of perioperativecomplications and reduce the amount of blood transfusion, while concurrent bilateral total kneereplacement can reduce the rate of deep infection. To further compare the efficacy and safety ofconcurrent or staged bilateral total knee arthroplasty, further studies must be conducted in theform of a randomized clinical trial to evaluate the results mentioned in this meta-analysis. 展开更多
关键词 KNEE OSTEOARTHRITIS ARTHROPLASTY STAGING simultaneous Meta analysis
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Non-isothermal kinetic analysis of thermal dehydration of La_2(CO_3)_3·3.4H_2O in air 被引量:3
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作者 张湘辉 何川 +3 位作者 汪灵 刘菁 邓苗 冯谦 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2014年第10期3378-3385,共8页
The single phase La2(CO3)3·3.4H2 O was synthesized by hydrothermal method. The thermal decomposition and intermediates and final solid products of La2(CO3)3·3.4H2O from 30 to 1000 °C were characteri... The single phase La2(CO3)3·3.4H2 O was synthesized by hydrothermal method. The thermal decomposition and intermediates and final solid products of La2(CO3)3·3.4H2O from 30 to 1000 °C were characterized by XRD, FTIR and DTA-TG. The kinetics of dehydration of La2(CO3)3·3.4H2O in the temperature range of 30-366 °C was investigated under non-isothermal conditions. Flynn-Wall-Ozawa and Friedman isoconversion methods were used to calculate the activation energy and analyze the reaction steps; multivariate non-linear regression program was applied to determine the most probable mechanism and the kinetic parameters. The results show that the thermal dehydration of La2(CO3)3·3.4H2O is a kind of three-step competitive reaction, and controlled by an n-order initial reaction followed by n-order competitive reaction(FnFnFn model). The activation energy matching with the most probable model is close to value obtained by Friedman method. The fitting curves match the original TG-DTG curves very well. 展开更多
关键词 La2(CO3)3·3.4H2O non-isothermal kinetics simultaneous thermal analysis dehydration reaction
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MOTION ANALYSIS OF TAPER MACHINING USING FOUR-AXIS WEDM MACHINE TOOL 被引量:3
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作者 王旭亮 谷安 《Transactions of Nanjing University of Aeronautics and Astronautics》 EI 2006年第2期149-153,共5页
The configuration and the reference frame of the four-axis wire-electric discharge machining (WEDM) machine tool are introduced. Based on the motion analysis of the four-axis WEDM machine tool, an algorithm for cont... The configuration and the reference frame of the four-axis wire-electric discharge machining (WEDM) machine tool are introduced. Based on the motion analysis of the four-axis WEDM machine tool, an algorithm for controlling the four-axis motion is proposed. The algorithm is applicable to both the invariable and variable taper machining. Motion loci of the machining platform and the wire guiding head are deduced by the algorithm according to the bottom surface locus of the workpiece and the taper angle. The algorithm is used in the CNC system of the four-axis WEDM machine tool and confirmed to be effective. 展开更多
关键词 WEDM TAPER four-axis simultaneous motion motion analysis
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Geochemical analysis of marine sediments using fused glass disc by X-ray fluorescence spectrometry 被引量:7
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作者 夏宁 张勤 +1 位作者 姚德 李国会 《Chinese Journal of Oceanology and Limnology》 SCIE CAS CSCD 2008年第4期475-479,共5页
A method was developed for content determination of Na, Mg, A1, Si, P,S, C1, K, Ca, Ti, V, Cr, Mn, Fe, Ni, Cu, Zn, Ga, Nb, Zr, Y, Sr, Rb, Ba, La and Ce etc. covering 26 major, minor, and trace elements in marine sedim... A method was developed for content determination of Na, Mg, A1, Si, P,S, C1, K, Ca, Ti, V, Cr, Mn, Fe, Ni, Cu, Zn, Ga, Nb, Zr, Y, Sr, Rb, Ba, La and Ce etc. covering 26 major, minor, and trace elements in marine sediment samples using fused glass disc by X-ray Fluorescence spectrometry. Calibration was made using marine sediment certified reference materials and the synthetic standard samples prepared by mixing several marine sediments with stream sediment and carbonate standard samples in different proportions. The matrix effect was corrected using theoretical alpha coefficients, experience coefficients and the scattered radiation as the internal standard (for the trace elements). The accuracy of the method was evaluated by analysis of certified reference materials GBW07314, GBW07334 and GSMS6. The results are in good agreement with the certified values of the standards with RSD less than 2.60%, except for Y, Cr, Ga, Ce, La, Nb, Rb, and V with RSD less than 9.0% (n=12). 展开更多
关键词 marine sediment X-ray fluorescence spectrometry geochemical analysis multi-element analysis
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Simultaneous Quantification of Ibuprofen and Paracetamol in Tablet Formulations Using Transmission Fourier Transform Infrared Spectroscopy 被引量:3
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作者 Muhammad Ali Mallah Syed Tufail Hussain Sherazi +1 位作者 Sarfaraz Ahmed Mahesar Abdul Rauf Khaskheli 《American Journal of Analytical Chemistry》 2012年第8期503-511,共9页
A very simple, non-destructive, inexpensive and green strategy was applied for the simultaneous determination of ibu-profen (IBP) and paracetamol (PC) using transmission Fourier Transform Infrared (FTIR) spectroscopy ... A very simple, non-destructive, inexpensive and green strategy was applied for the simultaneous determination of ibu-profen (IBP) and paracetamol (PC) using transmission Fourier Transform Infrared (FTIR) spectroscopy in tablet formulations for routine quality control laboratories. For the determination of the active pharmaceutical ingredients (API), KBr pellets containing known amount of standards and samples were used for acquisition of the FTIR spectra. The partial least squares (PLS) calibration model was developed using the spectral region from 1781 - 1683 cm-1 for IBP and 1630 - 1530 cm-1 for PC. The excellent coefficients of determination (R2), 0.9999 and 0.9998 were achieved for IBP and PC, respectively. The accuracy of calibration model was also verified through root mean square error of cross validation (RMSECV) which was found to be 0.064. This work clearly shows the capability of transmission FTIR spectroscopy for assessment of exact quantity of API to control the quality of finished products as well as during processing in pharmaceutical industries without involvement of any solvent. 展开更多
关键词 TRANSMISSION FTIR PHARMACEUTICAL Formulation IBUPROFEN PARACETAMOL simultaneous Determination Quantitative analysis
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An analysis and evaluation system of pulsed GMAW process based on LabVIEW 被引量:1
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作者 高莹 李桓 +2 位作者 凌礼恭 许贞龙 王颖 《China Welding》 EI CAS 2011年第3期22-26,共5页
A process evaluation system for pulsed gas metal arc welding (GMAW-P) based on the Lab V1EW platform has been developed. This system is comprised of two modules, a simultaneous display module and a data analysis mod... A process evaluation system for pulsed gas metal arc welding (GMAW-P) based on the Lab V1EW platform has been developed. This system is comprised of two modules, a simultaneous display module and a data analysis module. Using these modules, the system can not only provide a comprehensive direct viewing display of the welding electric signal and high speed camera photo, but also can analyze the characteristic parameters of the welding process. The results show that the system works properly. 展开更多
关键词 PULSE WELDING simultaneous display statistical analysis
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Decoupling Adaptive Sliding Mode Observer Design for Wind Turbines Subject to Simultaneous Faults in Sensors and Actuators 被引量:3
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作者 Hamed Habibi Ian Howard +1 位作者 Silvio Simani Afef Fekih 《IEEE/CAA Journal of Automatica Sinica》 SCIE EI CSCD 2021年第4期837-847,共11页
This paper proposes an adaptive sliding mode observer(ASMO)-based approach for wind turbines subject to simultaneous faults in sensors and actuators.The proposed approach enables the simultaneous detection of actuator... This paper proposes an adaptive sliding mode observer(ASMO)-based approach for wind turbines subject to simultaneous faults in sensors and actuators.The proposed approach enables the simultaneous detection of actuator and sensor faults without the need for any redundant hardware components.Additionally,wind speed variations are considered as unknown disturbances,thus eliminating the need for accurate measurement or estimation.The proposed ASMO enables the accurate estimation and reconstruction of the descriptor states and disturbances.The proposed design implements the principle of separation to enable the use of the nominal controller during faulty conditions.Fault tolerance is achieved by implementing a signal correction scheme to recover the nominal behavior.The performance of the proposed approach is validated using a 4.8 MW wind turbine benchmark model subject to various faults.Monte-Carlo analysis is also carried out to further evaluate the reliability and robustness of the proposed approach in the presence of measurement errors.Simplicity,ease of implementation and the decoupling property are among the positive features of the proposed approach. 展开更多
关键词 Fault tolerant control horizontal axis wind turbines Monte-Carlo analysis principle of separation simultaneous faults sliding mode observer
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A DDoS Attack Information Fusion Method Based on CNN for Multi-Element Data 被引量:1
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作者 Jieren Cheng Canting Cai +3 位作者 Xiangyan Tang Victor SSheng Wei Guo Mengyang Li 《Computers, Materials & Continua》 SCIE EI 2020年第4期131-150,共20页
Traditional distributed denial of service(DDoS)detection methods need a lot of computing resource,and many of them which are based on single element have high missing rate and false alarm rate.In order to solve the pr... Traditional distributed denial of service(DDoS)detection methods need a lot of computing resource,and many of them which are based on single element have high missing rate and false alarm rate.In order to solve the problems,this paper proposes a DDoS attack information fusion method based on CNN for multi-element data.Firstly,according to the distribution,concentration and high traffic abruptness of DDoS attacks,this paper defines six features which are respectively obtained from the elements of source IP address,destination IP address,source port,destination port,packet size and the number of IP packets.Then,we propose feature weight calculation algorithm based on principal component analysis to measure the importance of different features in different network environment.The algorithm of weighted multi-element feature fusion proposed in this paper is used to fuse different features,and obtain multi-element fusion feature(MEFF)value.Finally,the DDoS attack information fusion classification model is established by using convolutional neural network and support vector machine respectively based on the MEFF time series.Experimental results show that the information fusion method proposed can effectively fuse multi-element data,reduce the missing rate and total error rate,memory resource consumption,running time,and improve the detection rate. 展开更多
关键词 DDoS attack multi-element data information fusion principal component analysis CNN
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Ultra-performance liquid chromatography electrospray ionization-tandem mass spectrometry method for the simultaneous determination of itraconazole and hydroxy itraconazole in human plasma 被引量:1
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作者 Ashish Dwivedi Bhupinder Singh +2 位作者 Sandeep Sharma R.S.Lokhandae Naveen Dubey 《Journal of Pharmaceutical Analysis》 SCIE CAS 2014年第5期316-324,共9页
A highly sensitive, selective, and precise ultra-performance liquid chromatography tandem mass spectrometry method was developed and validated for simultaneous quantification of itraconazole and hydroxy itraconazole i... A highly sensitive, selective, and precise ultra-performance liquid chromatography tandem mass spectrometry method was developed and validated for simultaneous quantification of itraconazole and hydroxy itraconazole in human plasma by a single liquid-liquid extraction step. The precursor to product ion transitions of m/z 705.3/392.3, m/z 721.2/408.3 and m/z 708.2/435.4 were used to detect and quantify itraconazole, hydroxy itraconazole and itraconazole-d3 respectively. The lower limit of quantitation was found to be 0.500 ng/mL for itraconazole and 1.00 ng/mL for hydroxy itraconazole. The mean recoveries for itraconazole and hydroxy itraconazole were found to be 100.045% and 100.021%, respectively. This developed method with a chromatographic run time of 2.0 min was successfully applied to a bioequivalence study of 100 mg itraconazole capsule. 展开更多
关键词 Itraconazole Hydroxy itraconazole Ultra-performance liquidchromatography Human plasma simultaneous analysis
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Simultaneous Optimization of Incomplete Multi-Response Experiments 被引量:1
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作者 Pradip Kumar Nandi Rajender Parsad Vinod Kumar Gupta 《Open Journal of Statistics》 2015年第5期430-444,共15页
This article attempts to develop a simultaneous optimization procedure of several response variables from incomplete multi-response experiments. In incomplete multi-response experiments all the responses (p) are not r... This article attempts to develop a simultaneous optimization procedure of several response variables from incomplete multi-response experiments. In incomplete multi-response experiments all the responses (p) are not recorded from all the experimental units (n). Two situations of multi-response experiments considered are (i) on units all the responses are recorded while on units a subset of responses is recorded and (ii) on units all the responses (p) are recorded, on units a subset of responses is recorded and on units the remaining subset of responses is recorded. The procedure of estimation of parameters from linear multi-response models for incomplete multi-response experiments has been developed for both the situations. It has been shown that the parameter estimates are consistent and asymptotically unbiased. Using these parameter estimates, simultaneous optimization of incomplete multi-response experiments is attempted following the generalized distance criterion [1]. For the implementation of these procedures, SAS codes have been developed for both complete (k ≤ 5, p = 5) and incomplete (k ≤ 5, p1 = 2, 3 and p2 = 2, 3, where k is the number of factors) multi-response experiments. The procedure developed is illustrated with the help of a real data set. 展开更多
关键词 INCOMPLETE Multi-Response EXPERIMENTS simultaneous Optimization RESPONSE Surface DESIGNS RIDGE analysis
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Thermodynamic analysis of Na−S−Fe−H_(2)O system for Bayer process 被引量:1
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作者 Xue-jiao ZHOU Fei TAN +4 位作者 Yong-li CHEN Jian-guo YIN Wen-tang XIA Qing-yun HUANG Xu-dong GAO 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2022年第6期2046-2060,共15页
Thermodynamic diagrams of Na−S−Fe−H_(2)O system were constructed to analyze the behavior of sulfur and iron in the Bayer process.After digestion,iron mainly exists as Fe_(3)O_(4) and Fe_(2)O_(3) in red mud,and partial... Thermodynamic diagrams of Na−S−Fe−H_(2)O system were constructed to analyze the behavior of sulfur and iron in the Bayer process.After digestion,iron mainly exists as Fe_(3)O_(4) and Fe_(2)O_(3) in red mud,and partial iron transfers into solution as Fe(OH)_(3)^(−),HFeO_(2)^(−),Fe(OH)_(4)^(−)and Fe(OH)_(4)^(2−).The dominant species of sulfur is S^(2−),followed by SO_(4)^(2−),and then SO_(3)^(2−)and S_(2)O_(3)^(2−).The thermodynamic analysis is consistent with the iron and sulfur species distribution in the solution obtained by experiments.When the temperature decreases,sulfur and iron can combine and precipitate.Controlling low potential and reducing temperature are beneficial to removing them from the solution.XRD patterns show that NaFeS_(2)·2H_(2)O,FeS and FeS_(2) widely appear in red mud and precipitates of pyrite and high-sulfur bauxite digestion solution.Thermodynamic analysis can be utilized to guide the simultaneous removal of sulfur and iron in the Bayer process. 展开更多
关键词 high-sulfur bauxite Na−S−Fe−H_(2)O system thermodynamic analysis simultaneous removal SULFUR IRON Bayer process
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Simultaneous Determination of Uranium and Thorium with Standard Dual-addition Method
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作者 何荣桓 王建华 王玉宝 《Rare Metals》 SCIE EI CAS CSCD 1998年第2期75-80,共6页
dual-standard addition method was proposed and the principle of simultaneous determination for a interfering binary mixtures was discussed. The proposed procedure was applied to spectroscopic analyses for the simultan... dual-standard addition method was proposed and the principle of simultaneous determination for a interfering binary mixtures was discussed. The proposed procedure was applied to spectroscopic analyses for the simultaneous determination of uranium and thorium without prior separation. Various molar ratios of uranium/thorium, from 0.5∶1 to 10∶1, can be determined with satisfactory precision and accuracy. Uranium and thorium content in a phosphate ore and simulated sample were determined, the recoveries were 98.4%~102.5% for uranium and 96.8%~102.3% for thorium, the relative standard deviations (R.S.D) were 1.5%~2.3% for uranium and 2.1%~3.1% for thorium. 展开更多
关键词 Dual-standard addition method simultaneous determination URANIUM THORIUM Spectroscopic analysis
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Non-Isothermal Kinetic Analysis of Thermal Decomposition of the Ca-Bentonite from Santai, China
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作者 ZHANG Xianghui HE Chuan +3 位作者 WANG Ling DENG Miao LIU Jing FENG Qian 《矿物学报》 CAS CSCD 北大核心 2013年第S1期138-138,共1页
The thermal decompositions of Ca-bentonites (CaB) from Santai ,Shichuan Province, China over the temperature rage of 30-1100℃ were investigated by simultaneous thermal analyzer. Non-isothermal Kinetic analysis were e... The thermal decompositions of Ca-bentonites (CaB) from Santai ,Shichuan Province, China over the temperature rage of 30-1100℃ were investigated by simultaneous thermal analyzer. Non-isothermal Kinetic analysis were employed to study the thermal decomposition mechanism by using Netzsch Thermokinetics software. The dependence of the activation energy on conversion degree were evaluated by isoconversional methods. The probably mechanism and the corresponding kinetic parameters were determined by multivariate non-linear regression program. 展开更多
关键词 NON-ISOTHERMAL KINETIC simultaneous THERMAL analysis CA-BENTONITE THERMAL d
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Simultaneous Determination of Bufadienolides and Qualitative Evaluation for Venenum Bufonis by High Performance Liquid Chromatography
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作者 HUANG Hao LIANG Ming-jin +1 位作者 LUO Heng ZHANG Wei-dong 《Chemical Research in Chinese Universities》 SCIE CAS CSCD 2009年第6期801-806,共6页
A high performance liquid chromatographic method was used for the simultaneous identification and qualitative evaluation of 12 bufadienolides(resibufogenin, einobufagin, cinobufaginol, arenobufagin, bufalin, bufotali... A high performance liquid chromatographic method was used for the simultaneous identification and qualitative evaluation of 12 bufadienolides(resibufogenin, einobufagin, cinobufaginol, arenobufagin, bufalin, bufotalin, gamabufotalin, cinobufotalin, ψ-bufaranogin, desacetylcinobufagin, telocinobufagin and resibufogenol) in Venenum Bufonis. The chromatographic separation was performed on a Dikma C18 analytical column via gradient elution with an aqueous solution of acetonitrile and 0.3% acetic acid at a flow rate of 0.8 mL/min. The method was validated to be acceptable in consideration of linearity(r2 〉 0.9992) and recovery(ranged from 98.9% to 102.0%). The limits of detection of the bufadienolides were from 0.48 ng for bufalin to 6.00 ng for cinobufotalin. The intra-day and inter-day precisions of the method were evaluated and were less than 3.0%. The method was successfully used to analyze 19 batches of Venenum Bufonis, and the similarity values between batches were calculated by Similarity Evaluation System for Chromatographic Fingerprint of TCM(Version 2004A, Chinese Pharmacopoeia Committee, Beijing). The results show that the contents of bufadienolides in the medicine and the similarity values based on these bufadienolides varied significantly from batch to batch. This proposed method could be utilized to qualify and control Venenum Bufonis to ensure its safety and efficacy in application. 展开更多
关键词 BUFADIENOLIDE High performance liquid chromatography simultaneous analysis Qualitative evaluation Venenum Bufonis
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Simultaneous determination of fourteen components of Gumiganghwal-tang tablet in human plasma by UPLC-ESI-MS/MS and its application to pharmacokinetic study
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作者 Seung-Hyun Jeong Ji-Hun Jang +3 位作者 Guk-Yeo Lee Seung-Jung Yang Hea-Young Cho Yong-Bok Lee 《Journal of Pharmaceutical Analysis》 SCIE CAS CSCD 2021年第4期444-457,共14页
Gumiganghwal-tang is a traditional herbal medicine widely used for its anti-inflammatory,analgesic,and antipyretic effects.However,the safety and efficacy of its active ingredients based on an in vivo pharmacokinetic(... Gumiganghwal-tang is a traditional herbal medicine widely used for its anti-inflammatory,analgesic,and antipyretic effects.However,the safety and efficacy of its active ingredients based on an in vivo pharmacokinetic(PK)study have yet been investigated.We have established a sensitive and accurate UPLC-ESI-MS/MS method and conducted a PK study on 14 constituents of Gumiganghwal-tang through human plasma analysis.Analytical conditions were optimized according to the physicochemical properties of the 14 compounds to facilitate efficient separation and eliminate overlap or interference between peaks.KINETEX-C18 and Inertsil-C8 columns were used as UPLC stationary phases,and acetonitrile and aqueous formic acid were used as mobile phases.All the analytes were quantified with a triple quadrupole mass spectrometer using electrospray ionization in multiple reaction monitoring mode.The chromatograms of 14 bioactive compounds showed excellent elution and sensitivity,and each peak was selectively separated and quantified without interference with each other or impurities.The established analytical method was based on international guidelines and was successfully used to perform PK studies of 14 herbal ingredients in humans after oral administration with Gumiganghwal-tang tablets.The oral absorption of most active components of Gumiganghwal-tang was relatively rapid and remained considerably long in the body to be quantified in plasma up to 48 h after administration. 展开更多
关键词 Gumiganghwal-tang Fourteen bioactive ingredients simultaneous analysis UPLC-ESI-MS/MS PHARMACOKINETICS Clinical study
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