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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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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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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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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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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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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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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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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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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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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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Analysis of Solidification in Spray Atomized and Codeposited Metal-matrix Composites Part Ⅱ:Reinforcement Injection and Deposition 被引量:1
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作者 V. Erukhimovitch and J.Baram (Materials Engineering Department, Ben-Gurion University of Negev, Beer-Sheva, Israel) 《Journal of Materials Science & Technology》 SCIE EI CAS CSCD 1995年第3期165-170,共6页
The influence of the injection of reinforcing particles (for the production of metal matrix composites and of the droplets-to-substrate heat transfer on the resulting microstructural uniformity of spray atomized and c... The influence of the injection of reinforcing particles (for the production of metal matrix composites and of the droplets-to-substrate heat transfer on the resulting microstructural uniformity of spray atomized and codeposited composite material is analyzed. The reinforcement particles injection velocity has to be limited between an upper and a lower critical values. in order to ensure entrapment into the matrix droplets in flight. The thermal history of the injected droplets during the deposition stage is calculated with the assumption that the in-flight solidifying droplets reach the substrate while containing still at least 20% liquid volume fraction, in order to avoid porosity of the deposited material. The substrate to pouring-tube orifice distance where that condition is achieved depends strongly on the atomization pressure and the convective heat transfer coefficient of the substrate. It is demonstrated that 'tailoring' the microstructures and the reinforcement volume percent in the deposited material is feasible. The critical process parameters : the atomization pressure, the melt flow rate. the substrate to pouring-tube orifice distance, the reinforcement particles injection location and rate can all be adequately chosen in order to obtain any desired microstructure, grain size, reinforcement volume percent, with the additional benefit, if wanted, of rapid solidification processing 展开更多
关键词 analysis of Solidification in Spray Atomized and Codeposited Metal-matrix Composites Part Reinforcement Injection and Deposition Vc
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CAUSATION ANALYSIS OF THE DIRECT CLIMATE EFFECTS OF ANTHROPOGENIC AEROSOL ON EAST-ASIAN SUMMER MONSOON
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作者 王勇 吉振明 +1 位作者 沈新勇 陈明诚 《Journal of Tropical Meteorology》 SCIE 2016年第1期42-50,共9页
A regional climate model coupled with an aerosol model is employed to numerically simulate the direct climate effects of the anthropogenic aerosol emitted in South Asia and China in the East Asian summer monsoon durin... A regional climate model coupled with an aerosol model is employed to numerically simulate the direct climate effects of the anthropogenic aerosol emitted in South Asia and China in the East Asian summer monsoon during1988 to 2009.Based on the data of the numerical simulation,composite analysis and correlation analysis are used to make diagnostic study of climate dynamics.Results show that the month of maximum emission of the mean column burden of the anthropogenic aerosol in the main emission areas of South Asia is opposite in phase to that in China.Summer is the season of maximum emission amount in China,but the emission amounts are more in South Asia in spring and winter.On the whole,the mean column burden of the anthropogenic aerosol in China is relatively high compared with that in South Asia.The trend of distribution of aerosol is SW-NE in China,and Sichuan Basin is the emission center of aerosol.The effect of negative short wave radiative forcing alters the gradient of pressure between land and sea,weakening the development of East Asian summer monsoon over the northern part of Yangtze-Huaihe River Basin.We also discuss the feedback effect of East-Asian summer monsoon which is changed by the anthropogenic aerosol on the concentration and distribution of aerosol in China. 展开更多
关键词 East-Asian summer monsoon AEROSOL numerical simulation composite analysis correlation analysis
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ANALYSIS OF STRUCTURE EVOLUTION AND ENVIRONMENTAL CONDITIONS OF TROPICAL CYCLONES OVER THE WESTERN NORTH PACIFIC DURING EXTRATROPICAL TRANSITION
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作者 危国飞 朱佩君 +1 位作者 江佳 刘会军 《Journal of Tropical Meteorology》 SCIE 2017年第1期15-24,共10页
Fifty-eight extratropical transition(ET) cases in the years 2000-2008, including 2,021 observations(at 6-hour intervals), over the western North Pacific are analyzed using the cyclone phase space(CPS) method, in an ef... Fifty-eight extratropical transition(ET) cases in the years 2000-2008, including 2,021 observations(at 6-hour intervals), over the western North Pacific are analyzed using the cyclone phase space(CPS) method, in an effort to get the characteristics of the structure evolution and environmental conditions of tropical cyclones(TCs) during ET over this area. Cluster analysis of the CPS dataset shows that strong TCs are more likely to undergo ET. ET begins with the increment of thermal asymmetry in TCs, along with the generation and intensification of an upper-level cold core, and ends with the occurrence of a lower-level cold core. ET lasts an average duration of about 28 hours. Dynamic composite analysis of the environmental field of different clusters shows that, in general, when TCs move northward,they are gradually embedded in the westerlies and gradually transform into extratropical cyclones under the influence of the mid-and higher-latitude baroclinic systems. As for those TCs which complete ET, there is always much greater potential vorticity gradient in the northwest of them and obvious water vapor transport channels in the environment. 展开更多
关键词 extratropical transition of tropical cyclone cyclone phase space cluster analysis composite analysis
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Sea Breeze Front Storm and Its Composite Analysis in Beibu Gulf
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作者 LU Wei-ping LIANG Wei-liang +3 位作者 LI Jiang-nan LIN Zhen-min LIN Mo LI Jing 《Meteorological and Environmental Research》 CAS 2011年第9期20-23,27,共5页
[Objective] The aim was to study the sea breeze front storm and its composite analysis in Beibu Gulf. [Method] By dint of routine observation data, ground automatic meteorology data and European numerical mode grid da... [Objective] The aim was to study the sea breeze front storm and its composite analysis in Beibu Gulf. [Method] By dint of routine observation data, ground automatic meteorology data and European numerical mode grid data, rainstorm caused by sea breeze in Guangxi during 1990 and 2007 and the strong convection triggered by sea breeze on June 5 in 2008 were expounded. The main characteristics of the configuration of circulation in the low and high latitude of breeze front of middle scale were summarized. [Result] Sea breeze front storm system was an important middle scale sea breeze front system that triggered storm in the Beibu Gulf. Sea breeze in Beibu Gulf occurred most easily during the southwest monsoon eruption period. Case study pointed out that after sunrise, the continental and island temperature in Beibu Gulf turned from warm-ocean-cold-island into warm-island-cold-ocean. The southerly airstream of high temperature and high humidity met with the relatively low temperature and dry northerly airstream in Beibu Gulf, and triggered vertical circulation and stimulated ground middle scale sea breeze front system. Composite analysis referred to the circulation characteristics of the ocean and continental temperature in Beibu Gulf. The upper air of south China was in strong divergence center. The air pressure was high in the east and low in the west. Beibu Gulf was in the southerly torrent belt in front of the trough and after the latitude in cyclonic circulation convergence area. The strata unstable structure of the divergence in the upper air and the convergence in the lower layer and the 'pumping effect' provided upward dynamics for the ocean circulation development. The southerly brought rich water vapor to the Beibu Gulf, which was conductive to the formation of strong convective cloud system in the lower layer and the generation of precipitation. [Conclusion] The research provided references for the study on the characteristics of middle scale convective system. 展开更多
关键词 Beibu Gulf Sea breeze front CHARACTERISTICS Composite analysis China
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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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