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Influence of ear tags on the results of body composition analysis in mice
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作者 He Liu Yinghua Zhang +4 位作者 Peng Zhang Weiping Teng Zhongyan Shan Yushu Li Dan Wang 《Animal Models and Experimental Medicine》 CAS CSCD 2024年第4期578-583,共6页
Background:The aim of this study was to investigate the influence of marking meth-ods on the outcomes of body composition analysis and provide guidance for the se-lection of marking methods in mouse body composition a... Background:The aim of this study was to investigate the influence of marking meth-ods on the outcomes of body composition analysis and provide guidance for the se-lection of marking methods in mouse body composition analysis.Methods:Male C57BL/6J mice aged 6 weeks were randomly assigned for pre-and post-ear tagging measurements.The body composition of the mice was measured using a small animal body composition analyzer,which provided measurements of the mass of fat,lean,and free fluid.Then,the mass of fat,lean and free fluid to body weight ratio was gained.Further data analysis was conducted to obtain the range and coeffi-cient of variation in body composition measurements for each mouse.The distribution of fat and lean tissue in the mice was also analyzed by comparing the fat-to-lean ratio.Results:(1)The mass of all body composition components in the ear tagging group was significantly lower than that in the control group.(2)There was a significant in-crease in the range and coefficient of variation of body composition measurements between the ear tagging group and the control group.(3)The fat-to-lean ratio in the ear tagging group was significantly lower than that in the control group.Conclusions:Ear tagging significantly lowered the results of body composition analy-sis in mice and higher the results of measurement error.Therefore,ear tagging should be avoided as much as possible when conducting body composition analysis experi-ments in mice. 展开更多
关键词 body composition analysis ear tagging labeling method stainless steel toe clipping
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Elemental composition x-ray fluorescence analysis with a TES-based high-resolution x-ray spectrometer
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作者 吴秉骏 夏经铠 +4 位作者 张硕 傅强 章辉 谢晓明 刘志 《Chinese Physics B》 SCIE EI CAS CSCD 2023年第9期67-73,共7页
The accurate analysis of the elemental composition plays a crucial role in the research of functional materials.The emitting characteristic x-ray fluorescence(XRF)photons can be used for precisely discriminating the s... The accurate analysis of the elemental composition plays a crucial role in the research of functional materials.The emitting characteristic x-ray fluorescence(XRF)photons can be used for precisely discriminating the specified element.The detection accuracy of conventional XRF methodology using semiconductor detector is limited by the energy resolution,thus posing a challenge in accurately scaling the actual energy of each XRF photon.We adopt a novel high-resolution x-ray spectrometer based on the superconducting transition-edge sensor(TES)for the XRF spectroscopy measurement of different elements.Properties including high energy resolution,high detection efficiency and precise linearity of the new spectrometer will bring significant benefits in analyzing elemental composition via XRF.In this paper,we study the Ledge emission line profiles of three adjacent rare earth elements with the evenly mixed sample of their oxide components:terbium,dysprosium and holmium.Two orders of magnitude better energy resolution are obtained compared to a commercial silicon drift detector.With this TES-based spectrometer,the spectral lines overlapped or interfered by background can be clearly distinguished,thus making the chemical component analysis more accurate and quantitative.A database of coefficient values for the line strength of the spectrum can then be constructed thereafter.Equipped with the novel XRF spectrometer and an established coefficient database,a direct analysis of the composition proportion of a certain element in an unknown sample can be achieved with high accuracy. 展开更多
关键词 x-ray emission spectra and fluorescence superconducting transition-edge sensor rare earth elements chemical composition analysis
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Analysis of Effective Composition of Hippophae Rhamnoides L. 被引量:1
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作者 JIN Xiang jun Department of Chemistry, Baicheng Teacher College, Baicheng 137000, P. R. ChinaLUO Xu yang, WANG Ying, LIU Zai qun, ZHANG Jing wen and SUN Yun xiuCollege of Chemistry of Jilin University, Changchun 130023, P. R. China 《Chemical Research in Chinese Universities》 SCIE CAS CSCD 2002年第3期274-276,共3页
The vitamin E, proteins, amino acids, sugar, trace elements and fatty acids in the oil of Hippophae Rhamnoides L. seeds were quantitatively analyzed. Several methods for analyzing vitamin E were compared with eac... The vitamin E, proteins, amino acids, sugar, trace elements and fatty acids in the oil of Hippophae Rhamnoides L. seeds were quantitatively analyzed. Several methods for analyzing vitamin E were compared with each other and the content of gossypol in the oil was first determined. 展开更多
关键词 Hippophae Rhamnoides L. Seeds oil composition analysis
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Error Analysis of Non-English Major Students' Compositions and Lexical Teaching 被引量:3
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作者 Guirong Pan Zhuqing Wang 《Sino-US English Teaching》 2005年第4期57-60,共4页
The paper presented here investigates the kinds of lexical and grammatical errors made by Chinese EFL college students in their English compositions. Errors are then identified and .categorized to trace their causes. ... The paper presented here investigates the kinds of lexical and grammatical errors made by Chinese EFL college students in their English compositions. Errors are then identified and .categorized to trace their causes. The analysis of the errors along with the interviews of students and teachers show that vocabulary acquisition is one of the most important factors that affect the writing proficiency of the Chinese students especially the college students. Reasons for these errors are analyzed and suggestions are Out forward for reference. 展开更多
关键词 error analysis non-English major composition lexical teaching
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Using compositional data analysis to explore accumulation of sedentary behavior,physical activity and youth health
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作者 Simone J.J.M.Verswijveren Karen E.Lamb +11 位作者 Josep A.Martín-Fernández Elisabeth Winkler Rebecca M.Leech Anna Timperio Jo Salmon Robin M.Daly Ester Cerin David W.Dunstan Rohan M.Telford Richard D.Telford Lisa S.Olive Nicola D.Ridgers 《Journal of Sport and Health Science》 SCIE 2022年第2期234-243,共10页
Purpose:The study aimed to describe youth time-use compositions,focusing on time spent in shorter and longer bouts of sedentary behavior and physical activity(PA),and to examine associations of these time-use composit... Purpose:The study aimed to describe youth time-use compositions,focusing on time spent in shorter and longer bouts of sedentary behavior and physical activity(PA),and to examine associations of these time-use compositions with cardiometabolic biomarkers.Methods:Accelerometer and cardiometabolic biomarker data from 2 Australian studies involving youths 7-13 years old were pooled(complete cases with accelerometry and adiposity marker data,n=782).A 9-component time-use composition was formed using compositional data analysis:time in shorter and longer bouts of sedentary behavior;time in shorter and longer bouts of light-,moderate-,or vigorous-intensity PA;and"other time"(i.e.,non-wear/sleep).Shorter and longer bouts of sedentary time were defined as<5 min and>5 min,respectively.Shorter bouts of light-,moderate-,and vigorous-intensity PA were defined as<1 min;longer bouts were defined as≥1 min.Regression models examined associations between overall time-use composition and cardiometabolic biomarkers.Then,associations were derived between ratios of longer activity patterns relative to shorter activity patterns,and of each intensity level relative to the other intensity levels and"other time",and cardiometabolic biomarkers.Results:Confounder-adjusted models showed that the overall time-use composition was associated with adiposity,blood pressure,lipids,and the summary score.Specifically,more time in longer bouts of light-intensity PA relative to shorter bouts of light-intensity PA was significantly associated with greater body mass index z-score(zBMI)(β=1.79;SE=0.68)and waist circumference(β=18.35,SE=4.78).When each activity intensity was considered relative to all higher intensities and"other time",more time in light-and vigorous-intensity PA,and less time in sedentary behavior and moderate-intensity PA,were associated with lower waist circumference.Conclusion:Accumulating PA,particularly light-intensity PA,in frequent short bursts may be more beneficial for limiting adiposity compared to accumulating the same amount of PA at these intensities in longer bouts. 展开更多
关键词 Accumulation patterns Cardiometabolic health CHILDREN compositional data analysis Time-use
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Preliminary study on washability and composition analysis of high- sulfur coal in some mining areas in Guizhou
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作者 QIU Yue-qin MAO Song +2 位作者 ZHANG Qin TIAN Ye LIU Zhi-hong 《Journal of Coal Science & Engineering(China)》 2011年第1期93-95,共3页
Preliminary sink-float experiments on high-sulfur coal was done in some mining areas and carried on elementary analysis, industrial analysis, and ashcontent analysis. Through the experiments, definite middlings, and g... Preliminary sink-float experiments on high-sulfur coal was done in some mining areas and carried on elementary analysis, industrial analysis, and ashcontent analysis. Through the experiments, definite middlings, and gangue, the phase analysis of sulfur was carried on, by which a good understanding of sulfur characters in raw coal was achieved. 展开更多
关键词 High-sulfur coal sink-float experiments composition analysis sulfur phase analysis
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The Preparation Technology Research and Composition Analysis of Anti-fatigue Yikangshu Granules
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作者 Kun TANG Tong LIN +2 位作者 Chundan ZHANG Yanxia LU Shunxing GUO 《Medicinal Plant》 CAS 2021年第5期46-50,共5页
[Objectives]To optimize the preparation technology of Yikangshu granule,an anti-fatigue health food.[Methods]The process was studied from three aspects(raw material extraction,excipient selection and forming process),... [Objectives]To optimize the preparation technology of Yikangshu granule,an anti-fatigue health food.[Methods]The process was studied from three aspects(raw material extraction,excipient selection and forming process),and then it was verified in pilot production,and the content of the three components of the product was determined.[Results]The optimum production process of the formula granules was as follows:raw materials were extracted(adding 1∶9 water,extracting twice,2.5 h each time);vacuum concentration;adding excipients and mixing after vacuum drying,crushing and sieving;granulation of 75%ethanol sifted by a 20-mesh sieve;drying at 60℃,sifting through 14-mesh,and packaging.The average content of products obtained was as follows:crude polysaccharides(3204 mg/100 g),total saponins(2295 mg/100 g),astragaloside A(21 mg/100 g).[Conclusions]The optimized preparation technology is stable and feasible,and has a quality that can be controlled,which can provide a reference for the development of health food in food industry. 展开更多
关键词 ANTI-FATIGUE Health food Formula granules Technology research composition analysis
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Predictive Value of Body Composition Analysis for the Prognosis of Patients with Advanced Gastrointestinal Tumors
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作者 Hai Mei Yang Yi Zhuo Wang +4 位作者 Xiang Liang Liu Wei Ji Kai Wen Zheng Wei Li Jiu Wei Cui 《Journal of Nutritional Oncology》 2020年第4期182-188,共7页
Objective There is strong evidence that the body composition can affect the progression-free survival(PFS)and overall survival(OS)in patients with a variety of cancers.The main objective of this study was to investiga... Objective There is strong evidence that the body composition can affect the progression-free survival(PFS)and overall survival(OS)in patients with a variety of cancers.The main objective of this study was to investigate the effect of body composition on the prognosis of patients with advanced gastrointestinal and colorectal cancers who received first-line palliative chemotherapy.Methods Patients who were newly-diagnosed with advanced gastrointestinal or colorectal cancer and received standard first-line palliative chemotherapy from January 2017 to December 2018 were included in this retrospective study.An analysis of computed tomography images was performed to determine the skeletal muscle index(SMI),which reflects the skeletal muscle mass and skeletal muscle density(SMD)related to muscle strength.A Kaplan-Meier survival analysis and log-rank test were used to compare the survival relationships among groups stratified by the SMI,and a Cox proportional hazard model was used for a multivariate analysis.Results A total of 108 patients met the inclusion criteria,including 41 cases of gastric cancer,46 cases of left colorectal cancer,and 21 cases of right colon cancer.In patients with gastric cancer,the OS of women was significantly shorter than that of men.The OS of patients with a low SMI,low SMD,and low phase angle(PA)was significantly shorter than that of patients with high values(P≤0.05).In the multivariate analysis,the SMD was significantly associated with the patients'long-term survival[Hazard Ratio(HR)=0.904,95%CI:0.840~0.974,P=0.008].For patients with a low SMI and PA,the PFS was significantly shorter than that of patients with high values(P≤0.05).In patients with left colon cancer,the PA and SMD were both independent risk factors for a poorer long-term prognosis(HR=0.375,95%CI:=0.167~0.840,P=0.017;HR=0.887,95%CI:0.824~0.954,P=0.001).Among right colon cancer patients,the PFS and OS of those with a low SMD were significantly lower than those for patients with high values(P≤0.05).Conclusion The PA is an independent risk factor for the OS of left colon cancer patients;the SMD is an independent risk factor for the survival of patients with gastric cancer,left colon cancer,and right colon cancer. 展开更多
关键词 Body composition analysis Advanced gastrointestinal tumors Prognostic factor
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The impact of reabsorption effect on composition analysis of organic semiconductors
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作者 Bei Yang Xiaoke Liu +4 位作者 Li Wan Weixin Ni Ni Yang Jianhui Hou Feng Gao 《Science China Materials》 SCIE EI CAS CSCD 2024年第10期3124-3131,共8页
Reabsorption is one of the most fundamental optical phenomena,but it has rarely been considered in spectroscopy-based composition analysis for organic semiconductors.Here,we take four state-of-the-art organic solar ce... Reabsorption is one of the most fundamental optical phenomena,but it has rarely been considered in spectroscopy-based composition analysis for organic semiconductors.Here,we take four state-of-the-art organic solar cell(OSC)materials as examples,and systematically investigate the influence of reabsorption on photoluminescence emission and excitation spectra by both experimental studies and optical simulations.We find that the overlap between absorption and emission spectra of these OSC materials is strong enough for them to be affected by the reabsorption effect,and the effect becomes more obvious between different species in the multi-components systems.Moreover,three features of the reabsorption effect and the reabsorption strength are identified,with which we have successfully analyzed the composition in a range of OSC materials in both solution and solid-state films.Our work not only provides an important understanding of the largely overlooked feature of reabsorption in the widely used spectroscopic techniques but also offers an effective toolbox for the composition analysis of organic semiconductors. 展开更多
关键词 reabsorption effect composition analysis organic solar cells non-fullerene acceptors organic semiconductors
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Composition analysis of Compound Shenhua Tablet,a seven-herb Chinese medicine for IgA nephropathy:evaluation of analyte-capacity of the assays
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作者 ZHANG Haiyan WANG Qiuyue +12 位作者 WANG Jianan ZHANG Sichao JIA Weiwei HE Ning XIA Xiaoyan WANG Ting LAI Liyu LI Jiaying DU Jing OLALEYE Olajide E CHEN Xiangmei YANG Junling LI Chuan 《Chinese Journal of Natural Medicines》 SCIE CAS CSCD 2024年第2期178-192,共15页
Compound Shenhua Tablet,a medicine comprising seven herbs,is employed in treating IgA nephropathy.This study aimed to meticulously analyze its chemical composition.Based on a list of candidate compounds,identified thr... Compound Shenhua Tablet,a medicine comprising seven herbs,is employed in treating IgA nephropathy.This study aimed to meticulously analyze its chemical composition.Based on a list of candidate compounds,identified through extensive literature review pertinent to the tablet’s herbal components,the composition analysis entailed the systematic identification,characterization,and quantification of the constituents.The analyte-capacity of LC/ESI-MS-based and GC/EI-MS-based assays was evaluated.The identified and characterized constituents were quantified to determine their content levels and were ranked based on the constituents’daily doses.A total of 283 constituents,classified into 12 distinct categories,were identified and characterized in the Compound Shenhua Tablet.These constituents exhibited content levels of 1−10982μg·g^(−1),with daily doses of 0.01−395μmol·d^(−1).The predominant constituents,with daily doses of≥10μmol·d^(−1),include nine organic acids(citric acid,quinic acid,chlorogenic acid,cryptochlorogenic acid,gallic acid,neochlorogenic acid,isochlorogenic acid C,isochlorogenic acid B,and linoleic acid),five iridoids(specnuezhenide,nuezhenoside G13,nuezhenidic acid,secoxyloganin,and secologanoside),two monoterpene glycosides(paeoniflorin and albiflorin),a sesquiterpenoid(curzerenone),a triterpenoid(oleanolic acid),and a phenylethanoid(salidroside).Additionally,there were 83,126,and 55 constituents detected in the medicine with daily doses of 1–10,0.1–1,and 0.01–0.1μmol·d^(−1),respectively.The combination of the LC/ESI-MS-based and GC/EI-MS-based assays demonstrated a complementary relationship in their analyte-capacity for detecting the constituents present in the medicine.This comprehensive composition analysis establishes a solid foundation for further pharmacological research on Compound Shenhua Tablet and facilitates the quality evaluation of this complex herbal medicine. 展开更多
关键词 Compound Shenhua Tablet composition analysis Analyte-capacity
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Impacts of climate change and human activities on vegetation dynamics on the Mongolian Plateau, East Asia from 2000 to 2023
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作者 YAN Yujie CHENG Yiben +3 位作者 XIN Zhiming ZHOU Junyu ZHOU Mengyao WANG Xiaoyu 《Journal of Arid Land》 SCIE CSCD 2024年第8期1062-1079,共18页
The Mongolian Plateau in East Asia is one of the largest contingent arid and semi-arid areas of the world.Under the impacts of climate change and human activities,desertification is becoming increasingly severe on the... The Mongolian Plateau in East Asia is one of the largest contingent arid and semi-arid areas of the world.Under the impacts of climate change and human activities,desertification is becoming increasingly severe on the Mongolian Plateau.Understanding the vegetation dynamics in this region can better characterize its ecological changes.In this study,based on Moderate Resolution Imaging Spectroradiometer(MODIS)images,we calculated the kernel normalized difference vegetation index(kNDVI)on the Mongolian Plateau from 2000 to 2023,and analyzed the changes in kNDVI using the Theil-Sen median trend analysis and Mann-Kendall significance test.We further investigated the impact of climate change on kNDVI change using partial correlation analysis and composite correlation analysis,and quantified the effects of climate change and human activities on kNDVI change by residual analysis.The results showed that kNDVI on the Mongolian Plateau was increasing overall,and the vegetation recovery area in the southern region was significantly larger than that in the northern region.About 50.99%of the plateau showed dominant climate-driven effects of temperature,precipitation,and wind speed on kNDVI change.Residual analysis showed that climate change and human activities together contributed to 94.79%of the areas with vegetation improvement.Appropriate human activities promoted the recovery of local vegetation,and climate change inhibited vegetation growth in the northern part of the Mongolian Plateau.This study provides scientific data for understanding the regional ecological environment status and future changes and developing effective ecological protection measures on the Mongolian Plateau. 展开更多
关键词 kernel normalized difference vegetation index(kNDVI) human activities climate change partial correlation analysis composite correlation analysis residual analysis Mongolian Plateau
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Research progress of 24-hour movement behaviors in chronic non-communicable disease
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作者 Rong-Xuan Li Qing-Qing Fan Di Cui 《Life Research》 2024年第3期24-34,共11页
Chronic non-communicable diseases(NCDs)represent a significant impediment to improve life expectancy and remain a focal point in global public health and disease prevention efforts.24-hour movement behaviors,which inc... Chronic non-communicable diseases(NCDs)represent a significant impediment to improve life expectancy and remain a focal point in global public health and disease prevention efforts.24-hour movement behaviors,which include sleep,sedentary behavior(SED),and physical activity,underscore the inherent connections between different daily activities and the comprehensive impact of overall movement patterns on health.Evidence suggested that modifying patterns of 24-hour movement behaviors can aid in preventing and attenuating the progression of NCDs.This study systematically delineated the concept,evolution,analytical methods,and intrinsic associations of 24-hour movement behaviors,emphasizing their pivotal role in the prevention and management of NCDs such as obesity,mental disorders,cardiovascular diseases,diabetes,and renal diseases.Future research endeavors should focus on refining methodologies,broadening study populations,developing research tools,and exploring precise intervention strategies and interdisciplinary approaches to comprehensively enhance the effectiveness of NCDs prevention and management from a temporal perspective.Such efforts are poised to provide substantive guidance and support for public health practices. 展开更多
关键词 chronic non-communicable diseases 24-hour movement behaviors time-use epidemiology isotemporal substitution model compositional data analysis
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Application of Three Registers of FSG to Analyze Students' Compositions 被引量:1
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作者 谢贤春 《中国校外教育》 2008年第12期52-53,共2页
During the process of checking one of the students' composition,the author applies the field,tenor,and mode of FSC to analyze the writing in a broader way than before,which gives an enlightenment to teaching writi... During the process of checking one of the students' composition,the author applies the field,tenor,and mode of FSC to analyze the writing in a broader way than before,which gives an enlightenment to teaching writing and assisting students in a new angle. 展开更多
关键词 FSG teach writing composition analysis
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Development of a Laboratory Cement Quality Analysis Apparatus Based on Laser-Induced Breakdown Spectroscopy 被引量:2
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作者 樊娟娟 张雷 +10 位作者 王鑫 李郁芳 弓瑶 董磊 马维光 尹王保 王哲 李政 张向杰 李逸 贾锁堂 《Plasma Science and Technology》 SCIE EI CAS CSCD 2015年第11期897-903,共7页
Determination of the chemical composition of cement and ratio values of clinker plays an important role in cement plants as part of the optimal process control and product quality evaluation. In the present paper, a l... Determination of the chemical composition of cement and ratio values of clinker plays an important role in cement plants as part of the optimal process control and product quality evaluation. In the present paper, a laboratory laser-induced breakdown spectroscopy (LIBS) apparatus mainly comprising a sealed optical module and an analysis chamber has been designed for possible application in cement plants for on-site quality analysis of cement. Emphasis is placed on the structure and operation of the LIBS apparatus, the sealed optical path, the temperature controlled spectrometer, the sample holder, the proper calibration model established for minimizing the matrix effects, and a correction method proposed for overcoming the 'drift' obstacle. Good agreement has been found between the laboratory measurement results from the LIBS method and those from the traditional method. The absolute measurement errors presented here for oxides analysis are within 0.5%, while those of ratio values are in the range of 0.02 to 0.05. According to the obtained results, this laboratory LIBS apparatus is capable of performing reliable and accurate, composition and proximate analysis of cement and is suitable for application in cement plants. 展开更多
关键词 laser-induced breakdown spectroscopy LIBS CEMENT composition analysis proximate analysis ratio values linear correction method
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COMPOSITE ANALYSIS OF SUMMER MONSOON ONSET PROCESS OVER SOUTH CHINA SEA 被引量:3
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作者 徐海明 何金海 周兵 《Journal of Tropical Meteorology》 SCIE 2001年第1期29-40,共12页
Based on the method of composite analysis, the onset process and preceding signs of summer monsoon over the South China Sea (SCS) is investigated. The result indicates that convection activities appear first over the ... Based on the method of composite analysis, the onset process and preceding signs of summer monsoon over the South China Sea (SCS) is investigated. The result indicates that convection activities appear first over the Indo-China Peninsula prior to the onset of the monsoon, then around the Philippines just at the point of onset, implying that the convection activities around the Philippines serve as one of the reasons leading to the SCS monsoon onset. Before the SCS monsoon onset, the equatorial westerly over the Indian Ocean (75(E ~ 95(E ) experiences noticeable enhancement and plays an important role on the SCS monsoon onset. It propagates eastward rapidly and causes the establishment and strengthening of equatorial westerly in the southern SCS, on the one hand, it results in the migration southward of the westerly on south side of the south-China stationary front by means of shift northeastward of the westerly and convection over the Bay of Bengal, on the other. Further study also shows that the intensification of equatorial westerly in the Indian Ocean (75(E ~ 95(E) and the southern SCS is closely related to the reinforcement of the Southern-Hemisphere Mascarene high and Australian high, and cross-equatorial flow northward around Somali, at 85(E and 105(E, respectively. 展开更多
关键词 South China Sea summer monsoon onset process composite analysis
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ANALYSIS AND CALCULATION OF REGULATED WATER RESOURCES OF GROUNDWATER RESERVOIR 被引量:1
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作者 DAIChang-lei CHIBao-ming GAOShu-qin 《Chinese Geographical Science》 SCIE CSCD 2005年第1期60-63,共4页
Groundwater reservoir is a kind of important engineering, which can optimize water resources arran- gement by means of artificial regulation. Regulated water is the blood and value performance of groundwater reservoir... Groundwater reservoir is a kind of important engineering, which can optimize water resources arran- gement by means of artificial regulation. Regulated water is the blood and value performance of groundwater reservoir. To resolve the problem of real-time quantification of regulated water, the paper analyzed sources and compositions of regulated water in detail. Then, under the conditions of satisfying water demand inside research area, the paper analyzed quantity available and regulation coefficient of different regulated water and established a formula to calculate regulated water. At last, based on a pore groundwater reservoir in the middle reaches of the Yinma River, Jilin Province, the paper calculated regulated water with the formula and the result shows that the method is feasible. With some constraint conditions, the formula can be adopted in other similar areas. 展开更多
关键词 groundwater reservoir regulated water resources resources analysis composition analysis water quantity calculation
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COMPARATIVE ANALYSIS OF THE INTENSIFYING AND WEAKENING LANDFALL TROPICAL CYCLONES DURING EXTRATROPICAL TRANSITION OVER CHINA 被引量:1
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作者 李侃 徐海明 《Journal of Tropical Meteorology》 SCIE 2015年第1期23-33,共11页
Based on the Tropical Cyclone(TC) Yearbooks data and JRA-25 reanalysis data from the Japan Meteorological Agency(JMA) during 1979-2008, dynamic composite analysis and computation of kinetic energy budget are used to s... Based on the Tropical Cyclone(TC) Yearbooks data and JRA-25 reanalysis data from the Japan Meteorological Agency(JMA) during 1979-2008, dynamic composite analysis and computation of kinetic energy budget are used to study the intensifying and weakening TCs during Extratropical Transition over China. The TCI shows strong upper-level divergence, strengthened low-level convergence and significantly enhanced upward motion under the influence of strong upper-level troughs and high-level jets. The TCI is correspondingly intensified after Extratropical Transition(ET); TCW exhibits strong upper-level divergence, subdued low-level convergence and slightly enhanced upward motion under the influence of weak upper-level troughs and high-level jets. It then weakens after ET. The increase(decrease) of the generation of kinetic energy by divergence wind in TCI(TCW) at low level is one of the major reasons for TCI's intensification(TCW's weakening) after transformation. The generation of kinetic energy by divergence wind is closely related to the development of a low-level baroclinic frontal zone. The growth of the generation of kinetic energy by rotational wind in TCI at upper level is favorable for TCI's maintenance, which is affected by strong upper-level troughs. The dissipation of the generation of kinetic energy by rotational wind in TCW at upper level is unfavorable for TCW's maintenance, which is affected by weak upper-level troughs. 展开更多
关键词 tropical cyclone intensification during extratropical transition weakening during extratropical transition dynamic composite analysis kinetic energy budget
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STRUCTURE FEATURES AND COMPOSITE ANALYSIS OF CONVECTIVE CELLS IN A WARM SECTOR HEAVY RAINFALL EVENT OVER SOUTHERN CHINA 被引量:1
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作者 QIAN Lei DING Zhi-ying +1 位作者 ZHAO Xiang-jun XIA Fan 《Journal of Tropical Meteorology》 SCIE 2017年第3期245-258,共14页
This paper uses the ARW-WRF model to carry out a numerical simulation of a warm-sector heavy rainfall event over southern China on the 22-23 May, 2014. A composite analysis method was used to analyze the evolution pro... This paper uses the ARW-WRF model to carry out a numerical simulation of a warm-sector heavy rainfall event over southern China on the 22-23 May, 2014. A composite analysis method was used to analyze the evolution process and structural features of the convective cells on a convection line during this rainfall event. This analysis identified three stages:(1) Stage of activation: the equivalent potential temperature surfaces as lower layers start to bulge and form warm cells and weak vertical convective cloud towers which are subject to the impact of low-level warm moist updrafts in the rainfall sector;(2) Stage of development: the warm cells continue to bulge and form warm air columns and the convective cloud towers develop upwards becoming stronger as they rise;(3) Stage of maturity: the warm air columns start to connect with the stable layer in the upper air; the convective cloud tower will bend and tilt westward with each increasing in height, and the convection cell is characterized by a "crescent-shaped echo" above the 700 h Pa plane. During this stage the internal temperature of the cell is higher than the ambient temperature and the dynamic structural field is manifested as intensive vertical upward movement. The large-value centers of the northerly and westerly winds in the middle layer correspond to the warm moist center in the cells and the relatively cold center south of the warm air column. Further analysis shows that the formation of the "crescent-shaped" convective cell is associated with horizontal vorticity. Horizontal vorticity in the center and west of the warm cell experiences stronger cyclonic and anticyclonic shear transformation over time; this not only causes the original suborbicular cell echo shape to develop into a crescent-like shape, but also makes a convection line consisting of cells that develop to the northwest. 展开更多
关键词 convective cells structural features horizontal vorticity composite analysis
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Contrastive analysis and crashworthiness optimization of two composite thin-walled structures 被引量:4
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作者 谢素超 周辉 +1 位作者 梁习锋 任鑫 《Journal of Central South University》 SCIE EI CAS 2014年第11期4386-4394,共9页
For the safety protection of passengers when train crashes occur, special structures are crucially needed as a kind of indispensable energy absorbing device. With the help of the structures, crash kinetic-energy can b... For the safety protection of passengers when train crashes occur, special structures are crucially needed as a kind of indispensable energy absorbing device. With the help of the structures, crash kinetic-energy can be completely absorbed or dissipated for the aim of safety. Two composite structures(circumscribed circle structure and inscribed circle structure) were constructed. In addition, comparison and optimization of the crashworthy characteristic of the two structures were carried out based on the method of explicit finite element analysis(FEA) and Kriging surrogate model. According to the result of Kriging surrogate model, conclusions can be safely drawn that the specific energy absorption(SEA) and ratio of specific energy absorption to initial peak force(REAF) of circumscribed circle structure are lager than those of inscribed circle structure under the same design parameters. In other words, circumscribed circle structure has better performances with higher energy-absorbing ability and lower initial peak force. Besides, error analysis was adopted and the result of which indicates that the Kriging surrogate model has high nonlinear fitting precision. What is more, the SEA and REAF optimum values of the two structures have been obtained through analysis, and the crushing results have been illustrated when the two structures reach optimum SEA and REAF. 展开更多
关键词 contrastive analysis crashworthiness optimization composite structure Kriging surrogate model finite element analysis
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Prescription analysis of traditional chinese medicine for COVID-19treatment 被引量:1
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作者 Tong Niu Shi-Hong Zhong +2 位作者 Rong Ding Xin Bao Qin Liu 《Drug Combination Therapy》 2021年第1期14-27,共14页
Background:Coronavirus disease 2019 is still spreading all over the world and without any specific medicine.Traditional Chinese medicine has played an important role in the control of epidemics in China and accumulate... Background:Coronavirus disease 2019 is still spreading all over the world and without any specific medicine.Traditional Chinese medicine has played an important role in the control of epidemics in China and accumulated many experiences.The aim of this study is to summarize the law of traditional Chinese medicine and provide reference for coronavirus disease 2019 traditional Chinese medicine treatment.Methods:We collected the treatment plans of traditional Chinese medicine for coronavirus disease 2019 in 24 provinces of China to evaluate the basic Chinese medicine formulas,and the efficacy types,frequency,“Four Characters”,“Five Tastes”,“Channel Tropism”of herbal medicines.Combination rules between medicines were calculated by Apriori algorithm and Clementine12.0.Results:The formulas for“Relieving Exterior Syndrome”,“Expelling Dampness”,“Clearing Heat”and“Supplementing”have highest proportion.In prevention period and medical observation period,the medicines mainly have effect for“Clearing Heat”,“Relieving Exterior Syndrome”and“Supplementing”.In treatment period,medicines for“Clearing Heat”,“Relieving Superficies”and“Relieving Dampness”had higher frequency.The“Four Characters”of Chinese medicines in all treatment plans were mainly“Cold”and“Warm”.Medicines in the treatment plans always belong to“Pungent Taste”,“Bitter Taste”and“Sweet Taste”.For“Channel Tropism”,most medicines turned over to the“Lung”,“Stoma”and“Spleen”.The common medicine combinations in the recommended formulas during the prevention period and medical observation period were medicines for“Qi-Supplementing”and“Relieving Superficies”.In treatment period(mild,moderate,severe/critical),medicines for“Dampness Expelling”,“Relieving Superficies”and“Qi-Supplementing”were combined in a high frequency.In recovery period,the medicines for“Dispelling Dampness”combined the medicines for“Promoting Blood Circulation”with highest frequency.Conclusions:We found the characteristics of medicine and prescription rules of traditional Chinese medicine for the treatment of coronavirus disease 2019 and provided scientificity and effectiveness of it.More importantly,it provides reference for the development of new clinical prescriptions for coronavirus disease 2019. 展开更多
关键词 Coronavirus disease 2019 Formula of traditional Chinese medicine Chinese medicine compositional analysis of formulas
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