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Determination of Poliumoside and Forsythoside B in Different Parts of Callicarpa kwangtungensis and Its Plants from Different Habitats 被引量:1
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作者 李开斌 孙刚 +2 位作者 马四补 晏晨 李春植 《Agricultural Science & Technology》 CAS 2016年第5期1080-1082,1088,共4页
[Objective] This study was conducted to determinate the contents of poliumoside and forsythoside B in Callicarpa kwangtungensis,so as to reveal the distribution of two index components(poliumoside and forsythoside B... [Objective] This study was conducted to determinate the contents of poliumoside and forsythoside B in Callicarpa kwangtungensis,so as to reveal the distribution of two index components(poliumoside and forsythoside B) in the plant and to compare the contents of these components in the medicinal materials from different habitats.[Methods] Comparison and analysis of the contents of the two target components in different parts(root,branch,leaf and fruit) of Callicarpa kwangtungensis from the same habitat and in Callicarpa kwangtungensis from different production areas were performed according to the pharmacopoeia standard.[Result]The highest content of poliumoside wasdetected in fruit,and the content of forsythoside B was the highest in the branch.The contents of the two kinds of components were in order of branch fruit leafroot;The contents of the components were four times higher than China pharmacopeia(0.5%) in Jian,Tonggu,Anyuan,and Ganzhou of Jiangxi Province and the fifth area,Taijiang County of Qiandongnan Miao and Dong Autonomous Prefecture(QMDAP),among which Ganzhou and Taijiang showed the highest contents.[Conclusion] The differences of poliumoside and forsythoside B were obvious in different habitats and different parts of Callicarpa kwangtungensis. 展开更多
关键词 Callicarpa kwangtungensis CONTENTS different habitats different parts
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Simultaneous determination of Saikosaponin a, c and d in different parts of wild bupleurum from Shanxi Province 被引量:9
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作者 Rui Wang Ximei Yuan +2 位作者 Boya Ju Rui Liu Hongxia Yuan 《Journal of Chinese Pharmaceutical Sciences》 CAS CSCD 2018年第10期703-710,共8页
As a traditional Chinese herbal medicine exhibiting analgesic,fever-reducing and anti-inflammatory effects,Radix Bupleuri(Chai-Hu) is commonly used for the treatment of influenza,which is derived from the dried root... As a traditional Chinese herbal medicine exhibiting analgesic,fever-reducing and anti-inflammatory effects,Radix Bupleuri(Chai-Hu) is commonly used for the treatment of influenza,which is derived from the dried roots of Bupleurum chinense DC.and Bupleurum scorzonerifolium Willd.Among of diverse chemical components,saikosaponins are the key active components of the herb medicine.In the present study,we established a method of high performance liquid chromatography(HPLC) coupled with evaporative light scattering detection(ELSD) for simultaneous determination of saikosaponin a,c and d in root,stem,leaf and flower of Bupleurum chinense(B chinense) collected from different areas of Shanxi Province,China.The results from 16 samples of root,stem,leaf and flower of B chinense demonstrated that the total contents of the three saikosaponins in the root of B chinense collected from Dongshan Taiyuan,Xishan,Tianlongshan and Pangquangou were 4.26 mg/g,3.22 mg/g,4.23 mg/g and 3.05 mg/g,respectively.However,there was scarcely any saikosaponins in the stem,leaf and flower of B chinense collected from above-mentioned areas.The method of HPLC coupled with ELSD was suitable for quality control of Radix Bupleuri.The result also confirmed that the root of B chinense was the best medicinal part. 展开更多
关键词 Bupleurum chinense DC. different parts SAIKOSAPONINS Content analysis
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Analysis of Volatile Components in Different Parts of Polygala japonica Houtt.
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作者 Yushuo XIAO Jinqing LU +1 位作者 Jiamin MENG Li CAO 《Medicinal Plant》 CAS 2018年第1期6-8,共3页
[Objectives] To analyze the volatile components in different parts of Polygala japonica Houtt. and compare the differences of these volatile components. [Methods] The volatile components in different parts of P. japon... [Objectives] To analyze the volatile components in different parts of Polygala japonica Houtt. and compare the differences of these volatile components. [Methods] The volatile components in different parts of P. japonica Houtt. were analyzed by the headspace solid-phase microextraction( HS-SPME) combined with GC-MS,and the relative percentage of each component was determined by peak area normalization. [Results] Thirty kinds of volatile components were identified from the leaves and rhizomes of P. japonica Houtt.,mainly including olefins,aromatic hydrocarbons,alkanes and esters. [Conclusions] The volatile components in different parts of P. japonica Houtt. were different,and there may be difference in the medicinal value of volatile components in different parts,thus it is required to take an overall consideration of these differences in the development and utilization of P. japonica Houtt. 展开更多
关键词 Polygala japonica Houtt. Volatile components different parts Headspace solid-phase microextraction(HS-SPME) method
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Feasibility of establishing model of Parkinson disease by injecting 6-hydroxydopamine at different parts of the nigrostriatal pathway in the brain of rats
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作者 Yuefei Shen Xuean Mo Guifang Long 《Neural Regeneration Research》 SCIE CAS CSCD 2006年第2期126-129,共4页
BACKGROUND: Previous researches found that animal models with Parkinson disease (PD) could be established by injecting 6-hydroxydopamine (6-OHDA) into medial forebrain bundle (MFB), substantia nigra compacta (... BACKGROUND: Previous researches found that animal models with Parkinson disease (PD) could be established by injecting 6-hydroxydopamine (6-OHDA) into medial forebrain bundle (MFB), substantia nigra compacta (SNC) and caudate-putamen complex (CPU) of the nigrostriatal pathway. OBJECTIVE : To compare behavioral, biochemica 6-OHDA injections in the areas of MFB, SNC and DESIGN: Controlled observational study and histological properties of these rats undergoing the CPU respectively. SEI-IING: Department of Neurology, First Affiliated Hospital of Guangxi Medical University MATERIALS: A total of 64 adult female SD rats weighing 180-230 g were provided by the Animal Experimental Center of Guangxi Medical University. 6-OHDA (Sigma Company, USA); Brain solid positioner (Standard model 51600, Stoelting Co., IL, USA); rotational monitoring of little animal (type QL-1, USA); high liquid chromatography (HLC, Waters Company). METHOOS: The experiment was carried out in the Medical Experimental Center of Guangxi Medical University from February to December 2005. ① According to digital table, 64 SD rats were divided into MFB group, SNC group, CPU group and control group with 16 in each group. On the basis of the brain atlas of Paxinos, rats in the first three groups were injected with 5 μL 6-OHDA into right MFB (0 mm of line of incisor tooth, A/P 4.4 mm, L/R 1.2 mm, ON -7.8 mm), SNC (line of incisor tooth just equal to horizon, A/P -4.8 mm, L/R 1.6 mm, ON -7.8 mm) and CPU (0 mm of line of incisor tooth, A/P 1.2 mm, L/R 2.7 mm, ON -5.4 mm), respectively. The rats in control group were injected with 5 μL ascorbic acid solution (2 g/L). One week after operation, 0.1 g/L apomorphine (Apo, 0.05 mg/kg) was subcutaneously injected into neck and then rotational behavior induced by Apo was recorded once a week for 8 weeks. The PD models were considered successful only when rotational times more than or equal to 7 times per minute. Eight weeks after operation, micro-perfusion was used to obtain micro-perfusate in bilateral CPU and contents of 3,4-dihydroxyphenylacetic acid (3,4-DOPAC) and homovanillic acid (HVA) were also measured. In addition, amount of tyrosine hydroxylase positive cells (TH*) in SNC was counted with immuno- histochemical staining. MAIN OUTCOME MEASURES : ① Successful rate of PD models; ② contents of dopamine and its metabolite in MFB, SNC and CPU groups and TH* amount. RESULTS: All 64 SD rats were involved in the final analysis. ③ Successful rate and rotational behavior: One week after operation, there were 6 successful models both in SNC and MFB groups; in the 2^nd week, there were 6 both in SNC and MFB groups and 1 in CPU group; in the 3^nd week, there were 1 in MFB group and 3 in CPU group; in the 4^nd week, there were 3 in CPU group. Otherwise, no successful case was found out in the next 3 weeks. Abnormal rotational behavior was not observed in control group. Four weeks after operation, successful rates were 81% (13/16) in MFB group, 75% (12/16) in SNC group and 44% (7/16) in CPU group.② Contents of 3, 4-DOPAC and HVA: Eight weeks after operation, contents in the SNC area of the injured side were lower than those on non-lesion side (P 〈 0.01).③Changes of TH+ amount: Eight weeks after operation, TH+ amount in the SNC area of the lesion side was lower than that on non-lesion side (P 〈 0.01 ). CONCLUSION: Injecting 6-OHDA into MFB, SNC and CPU can damage dopaminergic cells and establish successful PD models. 展开更多
关键词 Feasibility of establishing model of Parkinson disease by injecting 6-hydroxydopamine at different parts of the nigrostriatal pathway in the brain of rats
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GC-MS Analysis of Chemical Components of Volatile Oil in Different Parts of Fennel( Foenicuzu vulgare Mill. ) 被引量:3
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作者 Wei CHEN Kaibin LI +4 位作者 Lina LONG Wen YANG Jianghai WANG Qiuyue KONG Fujun SUN 《Agricultural Biotechnology》 CAS 2020年第2期60-63,共4页
[Objectives] This study was conducted to analyze the composition of volatile oil in different parts of fennel(Foenicuzu vulgare Mill.) and to compare the differences in the composition of volatile oil in different par... [Objectives] This study was conducted to analyze the composition of volatile oil in different parts of fennel(Foenicuzu vulgare Mill.) and to compare the differences in the composition of volatile oil in different parts of fennel.[Methods]The steam distillation method was applied to extract volatile oil from different parts of fennel,and the components of volatile oil from different parts of fennel were separated and identified by GC-MS.The relative content of each component was determined by the peak area normalization method.[Results]37,33,18,and 44 chemical components were separated from the volatile oil of fennel roots,stems,young leaves and fruit,respectively,accounting for 98.64%,99.34%,99.59% and 95.99% of the total volatile oil of corresponding parts.A total of 77 chemical components were identified in the four parts,of which 5 were common components.The main component of the volatile oil in the stems and young leaves was trans-anethole.The main components of the volatile oil in fruit were estragole and trans-anethole.And the main component of the volatile oil in the roots was dill apiol.The components in the volatile oil of fennel roots,stems,young leaves and fruit were different in type and content.[Conclusions]This study provides a theoretical reference for the further effective development and utilization of fennel resources. 展开更多
关键词 Foenicuzu vulgare Mill. different partS VOLATILE OIL GC-MS
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HS-SPME-GC-MS Analysis on Volatile Components in Different Cultivars and Different Parts of Artemisia argyi 被引量:3
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作者 Li CAO Jinqing LU Xin YE 《Medicinal Plant》 2017年第4期1-5,9,共6页
[Objectives] To analyze and compare the difference in volatile components of different cultivars and different parts of Artemisia argyi by using headspace solid phase microextraction( HS-SPME) and provide scientific b... [Objectives] To analyze and compare the difference in volatile components of different cultivars and different parts of Artemisia argyi by using headspace solid phase microextraction( HS-SPME) and provide scientific basis for comprehensive development and rational utilization of Artemisia argyi. [Methods]Firstly,HS-SPME was used to extract the volatile components from the leaves,seeds,and stems of seven-tip Artemisia argyi,five-tip Artemisia argyi,and golden Artemisia argyi. Their chemical composition was analyzed by gas chromatographymass spectrometry( GC-MS),and the relative mass fraction of each component was determined by area normalization method. [Results] For the same variety of Artemisia argyi,the content of volatile components in leaves was higher than in seeds and stems except camphor,and the content of volatile components in seven-tip Artemisia argyi leaves was higher than in five-tip Artemisia argyi and golden Artemisia argyi leaves.HS-SPME-GC-MS analysis showed that eucalyptol,camphor,thujone,α-pinene,1-caryophyllene and caryophyllene oxide with higher content were detected in different parts of the different cultivars of Artemisia argyi. [Conclusions]Seven-tip Artemisia argyi leaves were the best medicinal parts of the three cultivars,followed by seven-tip Artemisia argyi seeds. 展开更多
关键词 ARTEMISIA argyi HS-SPME GC-MS different CULTIVARS different parts VOLATILE components
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Total Coumarin Content and Antioxidant Activity in Different Parts of Obazema, a Yi Medicine
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作者 Risha WEIZE Zhe LIU +3 位作者 Xuexue LI Jixiu SHEN Yuan LIU Ying LI 《Medicinal Plant》 CAS 2019年第5期39-44,共6页
[Objectives]This study aimed to determine the total coumarin content and antioxidant activity in vitro of Obazema,a Yi Medicine.[Methods]The extraction process of coumarin from Obazema was optimized by response surfac... [Objectives]This study aimed to determine the total coumarin content and antioxidant activity in vitro of Obazema,a Yi Medicine.[Methods]The extraction process of coumarin from Obazema was optimized by response surface method,and the total contents of coumarin in different sources and different parts of Obazema were compared.With Vc,chlorogenic acid and citric acid as positive controls,the antioxidant activity of the ethanol extracts of different parts of Obazema was determined.[Results]The optimum extraction process for coumarin from Obazema were as follows:80%ethanol,solid to liquid ratio 1∶67,extraction time 120 min and extraction temperature 57℃.The total contents of coumarin in roots,stems,leaves,flowers and fruit of Boenninghausenia sessilicarpa Levl.and B.albiflora(Hook.)Reichb.were 7.75,6.50,33.45 and 44.35,and 8.1,4.6,17.8 and 18.7 mg/g,respectively.The free radicle-scavenging activity of coumarin from Obazema had certain dose-effect relationship,and was slightly stronger than that of the positive drugs.Under the phenanthroline-Fe ^2+method,the free radicle-scavenging activity ranked as B.albiflora(Hook.)Reichb.>B.sessilicarpa Levl.>Vc>citric acid>chlorogenic acid;under the DPPH method,the free radicle-scavenging activity ranked as B.albiflora(Hook.)Reichb.>B.sessilicarpa Levl.>Vc>chlorogenic acid>citric acid;and under the ABSTS+method,the free radicle-scavenging capacity ranked was in the order as B.albiflora(Hook.)Reichb.>B.sessilicarpa Levl.>Vc>chlorogenic acid>citric acid.[Conclusions]There are significant differences in coumarin content between different sources and different parts of Obazema.When coumarin is used as the main active substance,Obazema is better harvested during the flowering period,and the free radicle-scavenging activity of B.sessilicarpa Levl.is higher than that of B.albiflora(Hook.)Reichb.The antioxidant activity of the flower-fruit ethanol extracts of B.sessilicarpa Levl.and B.albiflora(Hook.)Reichb.is stronger than that of the commonly used antioxidants such as Vc,chlorogenic acid and citric acid,which is related to antioxidant components in the ethanol extracts. 展开更多
关键词 Obazema YI MEDICINE different Source COUMARIN ANTIOXIDANT activity
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An Explicit Difference Scheme with High Accuracy and Branching Stability for Solving Parabolic Partial Differential Equation 被引量:4
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作者 马明书 王肖凤 《Chinese Quarterly Journal of Mathematics》 CSCD 2000年第4期98-103,共6页
This paper presents an explicit difference scheme with accuracy and branching stability for solving onedimensional parabolic type equation by the method of undetermined parameters and its truncation error is O(△t4+△... This paper presents an explicit difference scheme with accuracy and branching stability for solving onedimensional parabolic type equation by the method of undetermined parameters and its truncation error is O(△t4+△x4). The stability condition is r=a△t/△x2<1/2. 展开更多
关键词 parabolic type equation explicit difference scheme high accuracy branching stability truncation er
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Application of ~1H NMR-based metabolomics for discrimination of different parts and development of a new processing workflow for Cistanche deserticola 被引量:8
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作者 Pingping Zou Yuelin Song +3 位作者 Wei Lei Jun Li Pengfei Tu Yong Jiang 《Acta Pharmaceutica Sinica B》 SCIE CAS CSCD 2017年第6期647-656,676,共11页
Cistanche deserticola(CD) is one of the two authoritative source plants of Cistanches Herba, a well-known medicinal plant. Herein,~1H NMR spectroscopy was employed to characterize the chemical profile and to distingui... Cistanche deserticola(CD) is one of the two authoritative source plants of Cistanches Herba, a well-known medicinal plant. Herein,~1H NMR spectroscopy was employed to characterize the chemical profile and to distinguish the different parts, as well as to propose a new processing workflow for CD.Signal assignment was achieved by multiple one and two dimensional NMR spectroscopic techniques in combination with available databases and authentic compounds. The upper parts of the plant were distinguished from the lower parts by combining ~1H NMR spectroscopic dataset with multivariate statistical analysis. A new processing method that hyphenated steaming with freeze-drying, was demonstrated to be superior to either steaming coupled with oven-drying or direct freeze-drying via holistic ~1H NMR-based metabolomic characterization. Phenylethanoid glycosides, mainly echinacoside and acteoside, were screened out and confirmed as the chemical markers responsible for exhibiting the superiority of the new processing workflow, whereas serial primary metabolites, especially carbohydrates and tricarboxylic acid cycle metabolites, were found as the primary molecules governing the discrimination between the upper and lower parts of the plant. Collectively,~1H NMR spectroscopy was demonstrated as a versatile analytical tool to characterize the chemical profile and to guide the indepth exploitation of CD by providing comprehensive qualitative and quantitative information. 展开更多
关键词 Cistanche deserticola 1H NMR-based metabolomics Processing workflow different parts Phenylethanoid glycoside Tricarboxylic acid cycle metabolites ECHINACOSIDE ACTEOSIDE
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A Family of High_order Accuracy Explicit Difference Schemes for Solving 2-D Parabolic Partial Differential Equation 被引量:4
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作者 任宗修 陈贞忠 王肖凤 《Chinese Quarterly Journal of Mathematics》 CSCD 2002年第3期57-61,共5页
A family of high_order accuracy explicit difference schemes for solving 2_dimension parabolic P.D.E. are constructed. Th e stability condition is r=Δt/Δx 2=Δt/Δy 2【1/2 and the truncation err or is O(Δt 3+Δx... A family of high_order accuracy explicit difference schemes for solving 2_dimension parabolic P.D.E. are constructed. Th e stability condition is r=Δt/Δx 2=Δt/Δy 2【1/2 and the truncation err or is O(Δt 3+Δx 4). 展开更多
关键词 D parabolic P.D.E high_order accuracy explic it difference scheme
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THE EVALUATION METHODS OF VELVET ANTLER AND THE DETERMINATION OF NUCLEOSIDES AND STEROID HORMONES IN DIFFERENT PARTS FROM SIKA DEER AND RED DEER
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作者 Zhenghong Guo Ting Xiao +1 位作者 Feng Xiao Yuqing Zhao 《World Journal of Traditional Chinese Medicine》 2015年第4期107-107,共1页
Velvet antler is an important and precious traditional Chinese animal medicine,and was used for strengthening the kidney,anti-fatigue,improving sexual function and so on.But the evaluation methods of velvet antler and... Velvet antler is an important and precious traditional Chinese animal medicine,and was used for strengthening the kidney,anti-fatigue,improving sexual function and so on.But the evaluation methods of velvet antler and the scientific evidence for the use of antler is insufficient.Materials and Vacuum freeze drier was used for dehydration of the fresh antler at-60.,6 pa for 24 h. 展开更多
关键词 THE EVALUATION METHODS OF VELVET ANTLER AND THE DETERMINATION OF NUCLEOSIDES AND STEROID HORMONES IN different partS FROM SIKA DEER AND RED DEER
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Influence of different weather events on concentrations of particulate matter with different sizes in Lanzhou,China 被引量:20
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作者 Xinyuan Feng Shigong Wang 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2012年第4期665-674,共10页
The formation and development of weather events has a great impact on the diffusion, accumulation and transport of air pollutants, and causes great changes in the particulate pollution level. It is very important to s... The formation and development of weather events has a great impact on the diffusion, accumulation and transport of air pollutants, and causes great changes in the particulate pollution level. It is very important to study their influence on particulate pollution. Lanzhou is one of the most particulate-polluted cities in China and even in the world. Particulate matter (PM) including TSP, PM〉10, PMzs-10, PM2.5 and PM1.0 concentrations were simultaneously measured during 2005-2007 in Lanzhou to evaluate the influence of three kinds of weather events - dost, precipitation and cold front - on the concentrations of PM with different sizes and detect the temporal evolution. The main results are as follows: (1) the PM pollution in Lanzhou during dust events was very heavy and the rate of increase in the concentration of PM2.5-10 was the highest of the five kinds of particles. During dust-storm events, the highest peaks of the concentrations of fine particles (PM2.5 and PM1.0) occurred 3 hr later than those of coarse particles (PM〉10 and PM/.5-10). (2) The major effect of precipitation events on PM is wet scavenging. The scavenging rates of particles were closely associated with the kinds of precipitation events. The scavenging rates of TSP, PM〉10 and PMa.5-10 by convective precipitation were several times as high as those caused by frontal precipitation for the same precipitation amount, the reason being the different formation mechanism and precipitation characteristics of the two kinds of precipitation. Moreover, there exists a limiting value for the scavenging rates of particles by precipitation. (3) The major effect of cold-front events on particles is clearance. However, during cold-front passages, the PM concentrations could sometimes rise first and decrease afterwards, which is the critical difference in the influence of cold fronts on the concentrations of particulate pollutants vs. gaseous pollutants. 展开更多
关键词 particulate matter with different sizes dust event precipitation event cold-front event
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High school sports programs differentially impact participation by sex 被引量:3
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作者 Keith M. Drake Meghan R. Longacre +4 位作者 Todd MacKenzie Linda J. Titus Michael L. Beach Andrew G. Rundle Madeline A. Dalton 《Journal of Sport and Health Science》 SCIE 2015年第3期282-288,共7页
Background: Among numerous health benefits, sports participation has been shown to reduce the risk of overweight and obesity in children and adolescents. Schools represent an ideal environment for increasing sports p... Background: Among numerous health benefits, sports participation has been shown to reduce the risk of overweight and obesity in children and adolescents. Schools represent an ideal environment for increasing sports participation, but it is unclear how access and choice influence participation and whether characteristics of the school sports program differentially influence boys' and girls' participation. The purpose of this study was to evaluate the characteristics of high school athletic programs and determine the extent to which these characteristics influenced boys' and girls' sports team participation. Methods: Longitudinal telephone surveys were conducted with 1244 New Hampshire and Vermont students. Students self-reported their sports team participation at baseline (elementary school) and follow-up (high school). High school personnel were surveyed to assess sports oppor- tunities, which were defined for this analysis as the number of sports offered per 100 students (i.e., choice) and the percent of sports offered that did not restrict the number of players (i.e., access). Results: Approximately 70% of children participated on at least one sports team, including 73% of boys and 66% of girls. We detected sta- tistically significant interactions between sex and two school opportunity variables: 1) the number of sports offered per 100 students (i.e., choice) and 2) the percent of sports offered that did not restrict the number of players (i.e., access). After controlling for children's baseline sports participation and other covariates, boys were more likely to play on at least one sports team per year if their school did not restrict participation in the most popular sports (relative risk, RR = 1.12, p 〈 0.01); in contrast, girls were more likely to play on at least one sports team per year if their school offered a wider variety of sports (RR = 1.47, p 〈 0.001). Conclusion: Sports participation has previously been shown to confer a number of health benefits; as such, school sports programs may be an important, effective, and underused target for public health efforts, including obesity prevention programs. Efforts to increase physical activity among youth should consider both access and choice in school athletic programs. Schools may need to use different strategies to increase sports participation in boys and girls. 展开更多
关键词 Adolescents Gender equity High school students School athletic programs Sex differences Sports participation
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Rapid recognition of Chinese herbal pieces of Areca catechu by different concocted processes using Fourier transform mid-infrared and near-infrared spectroscopy combined with partial least-squares discriminant analysis 被引量:12
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作者 Hai-Yan Fu Dong-Chen Huang +2 位作者 Tian-Ming Yang Yuan-Bin She Hao Zhang 《Chinese Chemical Letters》 SCIE CAS CSCD 2013年第7期639-642,共4页
Rapid and sensitive recognition of herbal pieces according to different concocted processing is crucial to quality control and pharmaceutical effect. Near-infrared (NIR) and mid-infrared (MIR) technology combined ... Rapid and sensitive recognition of herbal pieces according to different concocted processing is crucial to quality control and pharmaceutical effect. Near-infrared (NIR) and mid-infrared (MIR) technology combined with supervised pattern recognition based on partial least-squares discriminant analysis (PLSDA) was attempted to classify and recognize six different concocted processing pieces of 600 Areca catechu L. samples and the influence of fingerprint information preprocessing methods on recognition performance was also investigated in this work. Recognition rates of 99.24%, 100% and 99.49% for original fingerprint, multiple scatter correct (MSC) fingerprint and second derivative (2nd derivative) fingerprint of NIR spectra were achieved by PLSDA models, respectively. Meanwhile, a perfect recognition rate of 100% was obtained for the above three fingerprint models of MIR spectra. In conclusion, PLSDA can rapidly and effectively extract otherness of fingerprint information from NIR and MIR spectra to identify different concocted herbal pieces ofA. catechu. 展开更多
关键词 NIR and MIR spectroscopy partial least-squares discriminant analysis different concocted processing herbal pieces
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Remaining Useful Life Prediction of Rolling Element Bearings Based on Different Degradation Stages and Particle Filter 被引量:1
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作者 LI Qing MA Bo LIU Jiameng 《Transactions of Nanjing University of Aeronautics and Astronautics》 EI CSCD 2019年第3期432-441,共10页
A method is proposed to improve the accuracy of remaining useful life prediction for rolling element bearings,based on a state space model(SSM)with different degradation stages and a particle filter.The model is impro... A method is proposed to improve the accuracy of remaining useful life prediction for rolling element bearings,based on a state space model(SSM)with different degradation stages and a particle filter.The model is improved by a method based on the Paris formula and the Foreman formula allowing the establishment of different degradation stages.The remaining useful life of rolling element bearings can be predicted by the adjusted model with inputs of physical data and operating status information.The late operating trend is predicted by the use of the particle filter algorithm.The rolling bearing full life experimental data validate the proposed method.Further,the prediction result is compared with the single SSM and the Gamma model,and the results indicate that the predicted accuracy of the proposed method is higher with better practicability. 展开更多
关键词 different LIFE STAGES of state space model REMAINING useful LIFE prediction of ROLLING element bearing particle filter
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Simulation of random mixed packing of different density particles 被引量:1
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作者 李元元 夏伟 +3 位作者 周照耀 何克晶 钟文镇 吴苑标 《Chinese Physics B》 SCIE EI CAS CSCD 2010年第2期336-341,共6页
This paper presents the effects of density difference on the three-dimensional (3D) distribution of random mixed packing. The random mixed packing dynamics of particles of two different densities are simulated. The ... This paper presents the effects of density difference on the three-dimensional (3D) distribution of random mixed packing. The random mixed packing dynamics of particles of two different densities are simulated. The initial state is homogeneous, but the final packing state is inhomogeneous. The segregation phenomenon (inhomogeneous distribution) is also observed. In the final state, the top layers are composed of mostly light particles. The several layers beneath the top contain more heavy particles than light particles. At the bottom, they also contain more heavy particles than light particles. Furthermore, at both the top and the bottom, particle clustering is observed. The current study also analyses the cause of this inhomogeneity in detail. The main cause of this phenomenon is the velocity difference after collision of these two types of particles induced by the density difference. The present study reveals that even if particles were perfectly mixed, the packing process would lead to the final inhomogeneous mixture. It suggests that special treatment may be required to get the true homogeneous packing. 展开更多
关键词 mixed packing different densities granular particle discrete element method simulation
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High room-temperature magnetization in Co-doped TiO_(2) nanoparticles promoted by vacuum annealing for different durations 被引量:1
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作者 Wenqiang Huang Rui Lin +2 位作者 Weijie Chen Yuzhu Wang Hong Zhang 《Journal of Semiconductors》 EI CAS CSCD 2021年第7期71-77,共7页
To clarify the contribution of oxygen vacancies to room-temperature ferromagnetism(RTFM)in cobalt doped TiO_(2)(Co-TiO_(2)),and in order to obtain the high level of magnetization suitable for spintronic devices,in thi... To clarify the contribution of oxygen vacancies to room-temperature ferromagnetism(RTFM)in cobalt doped TiO_(2)(Co-TiO_(2)),and in order to obtain the high level of magnetization suitable for spintronic devices,in this work,Co-TiO_(2) nano-particles are prepared via the sol-gel route,followed by vacuum annealing for different durations,and the influence of vacu-um annealing duration on the structure and room-temperature magnetism of the compounds is examined.The results reveal that with an increase in annealing duration,the concentration of oxygen vacancies rises steadily,while the saturation magnetiza-tion(Ms)shows an initial gradual increase,followed by a sharp decline,and even disappearance.The maximum Ms is as high as 1.19 emu/g,which is promising with respect to the development of spintronic devices.Further analysis reveals that oxygen va-cancies,modulated by annealing duration,play a critical role in tuning room-temperature magnetism.An appropriate concentra-tion of oxygen vacancies is beneficial in terms of promoting RTFM in Co-TiO_(2).However,excessive oxygen vacancies will result in a negative impact on RTFM,due to antiferromagnetic superexchange interactions originating from nearest-neighbor Co^(2+)ions. 展开更多
关键词 Co-doped TiO_(2)nanoparticles room-temperature ferromagnetism different annealing duration oxygen vacancy high magnetization
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A Computational Study with Finite Element Method and Finite Difference Method for 2D Elliptic Partial Differential Equations 被引量:2
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作者 George Papanikos Maria Ch. Gousidou-Koutita 《Applied Mathematics》 2015年第12期2104-2124,共21页
In this paper, we consider two methods, the Second order Central Difference Method (SCDM) and the Finite Element Method (FEM) with P1 triangular elements, for solving two dimensional general linear Elliptic Partial Di... In this paper, we consider two methods, the Second order Central Difference Method (SCDM) and the Finite Element Method (FEM) with P1 triangular elements, for solving two dimensional general linear Elliptic Partial Differential Equations (PDE) with mixed derivatives along with Dirichlet and Neumann boundary conditions. These two methods have almost the same accuracy from theoretical aspect with regular boundaries, but generally Finite Element Method produces better approximations when the boundaries are irregular. In order to investigate which method produces better results from numerical aspect, we apply these methods into specific examples with regular boundaries with constant step-size for both of them. The results which obtained confirm, in most of the cases, the theoretical results. 展开更多
关键词 FINITE Element METHOD FINITE Difference METHOD Gauss Numerical Quadrature DIRICHLET BOUNDARY CONDITIONS NEUMANN BOUNDARY CONDITIONS
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Total Ionizing Dose Response of Different Length Devices in 0.13μm Partially Depleted Silicon-on-Insulator Technology 被引量:1
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作者 张梦映 胡志远 +4 位作者 张正选 樊双 戴丽华 刘小年 宋雷 《Chinese Physics Letters》 SCIE CAS CSCD 2017年第8期144-147,共4页
An anomalous total dose effect that the long length device is more susceptible to total ionizing dose than the short one is observed with the 0.13?μm partially depleted silicon-on-insulator technology. The measured ... An anomalous total dose effect that the long length device is more susceptible to total ionizing dose than the short one is observed with the 0.13?μm partially depleted silicon-on-insulator technology. The measured results and 3D technology computer aided design simulations demonstrate that the devices with different channel lengths may exhibit an enhanced reverse short channel effect after radiation. It is ascribed to that the halo or pocket implants introduced in processes results in non-uniform channel doping profiles along the device length and trapped charges in the shallow trench isolation regions. 展开更多
关键词 PDSOI Total Ionizing Dose Response of different Length Devices in 0.13 m partially Depleted Silicon-on-Insulator Technology
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An Introduction to Numerical Methods for the Solutions of Partial Differential Equations 被引量:1
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作者 Manoj Kumar Garima Mishra 《Applied Mathematics》 2011年第11期1327-1338,共12页
Partial differential equations arise in formulations of problems involving functions of several variables such as the propagation of sound or heat, electrostatics, electrodynamics, fluid flow, and elasticity, etc. The... Partial differential equations arise in formulations of problems involving functions of several variables such as the propagation of sound or heat, electrostatics, electrodynamics, fluid flow, and elasticity, etc. The present paper deals with a general introduction and classification of partial differential equations and the numerical methods available in the literature for the solution of partial differential equations. 展开更多
关键词 partial differential EQUATIONS EIGENVALUE FINITE Difference METHOD FINITE Volume METHOD FINITE Element METHOD
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