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Comparative analysis of frame strength standards for intelligent urban rail vehicles
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作者 Li Bing Xu Hongwei Zhang Xiangjie 《China Standardization》 2025年第3期52-55,共4页
The rapid development and application of emerging information technologies,such as big data and artificial intelligence,facilitates the development of intelligent urban rail vehicles.Architecture is an important compo... The rapid development and application of emerging information technologies,such as big data and artificial intelligence,facilitates the development of intelligent urban rail vehicles.Architecture is an important component of intelligent urban rail vehicles and a key factor in ensuring their reliable and safe operation on various routes.In this context,it is very important to select appropriate architecture design standards.The paper reviews the relevant design standards for architecture at home and abroad,comprehensively analyzes the standards that need to be compared and analyzed,and conducts comprehensive comparative analysis in the aspects of the scope of application,load conditions,vertical static load,lateral load,and evaluation methods of the standards.Finally,it draws a conclusion that the standard JIS E 4207:2019,Rolling stock—Bogie—General rules for design of bogie frame strength,can meet the requirements of strength design of welded bogie frame in intelligent urban rail vehicles.It proposes the suggestions on better validating this design method in future bench and line tests of products,in order to improve the design concept of bogie frame strength and provide reference and inspiration for promoting the development of intelligent urban rail vehicles in China. 展开更多
关键词 intelligent urban rail vehicles structural strength STANDARD comparative analysis
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Comparative seismic performance analysis of steel braced frames with resilient slip-friction joint braces and buckling-restrained braces
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作者 Rajnil Lal Ashkan Hashemi +2 位作者 Nicholas Chan Setu Agarwal Pierre Quenneville 《Resilient Cities and Structures》 2025年第3期30-47,共18页
Self-centering systems are increasingly studied after devastating earthquakes in the 2010s that caused irreparable damage to buildings.Currently,there is conflicting evidence as to whether the re-centering(restoring)c... Self-centering systems are increasingly studied after devastating earthquakes in the 2010s that caused irreparable damage to buildings.Currently,there is conflicting evidence as to whether the re-centering(restoring)capabilities are gained at the expense of hysteretic damping,potentially leading to larger peak displacements and damage to non-structural elements.This study examines the earthquake response of self-centering and non-self-centering systems through analyses of 4-storey and 8-storey steel-braced frames.The Resilient Slip Friction Joint(RSFJ)dampers,combined with steel braces in series,represent the self-centering bracing system,whereas the Buckling Restrained Braces(BRBs)represent the non-self-centering bracing system.Results suggest that peak displacements,base shears,and floor accelerations were comparable between the two systems.A possible explanation is that the peak response occurs on the first major excursion;similar peaks result from similar backbone curves in the run-up to the peak.Conversely,the amount of hysteretic damping only begins to affect the post-peak behavior.For instance,the RSFJ system reintroduces seismic energy into the structure post-peak(rather than dissipating it like the BRB).Subsequently,it leads to larger vibration amplitudes about the central position,increasing the risk of secondary peaks.This contrasts with the BRB system,which exhibits smaller vibration amplitudes about an increasingly deformed position due to seismic ratcheting.Unsurprisingly,residual deformations were high for the BRBs(1.7%on average)and negligible for the RSFJ.However,RSFJ produced smaller peak inter-storey drifts between 13%–18%but higher peak accelerations by 4%–5%.The results suggest that multi-storey braced frames could be designed with similar or smaller forces when self-centering systems are used. 展开更多
关键词 comparative analysis Buckling-restrained braces BRB Resilient slip-friction joint RSFJ
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Comparative Analysis of Marketing Research between China and United Kingdom
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作者 Qianyu Li 《Proceedings of Business and Economic Studies》 2025年第2期326-333,共8页
This paper conducts clustering,potential semantic indexing,comparison,and inductive analysis of research papers on marketing between China and the UK from January 2020 to September 2024.The study found that the Chines... This paper conducts clustering,potential semantic indexing,comparison,and inductive analysis of research papers on marketing between China and the UK from January 2020 to September 2024.The study found that the Chinese marketing research focuses on digital transformation,policy impact,value co-creation,and emerging e-commerce models.In contrast,the UK marketing research focuses more on sustainability,technology integration,real-time research,and personalized marketing strategies.The study also found that there were few marketing articles published in Chinese and CSSCI journals in China,while the SSCI journals published in English were 62 times more than in Chinese.According to the research,digital marketing and data-driven decision-making,diversified marketing channels,sustainability and circular economy,technological innovation and cutting-edge technology application,meta-universe and blockchain technology,AI+marketing development,brand building,and international market expansion will become the research hotspots in the field of marketing in the future.The research suggests that China should strengthen the construction of an academic marketing platform,and China and the UK should strengthen cooperation in marketing research,learn from each other's strengths,and jointly give full play to their advantages in technology application,market and economy,strategy and innovation,and social media,to contribute to global economic development and marketing research. 展开更多
关键词 China and Britain Marketing research comparative analysis
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A Comparative Analysis and Implications of Research on International Chinese Language Teachers’Professional Identity from a Global Perspective
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作者 Liqiang Xu 《Journal of Contemporary Educational Research》 2025年第7期1-12,共12页
Teacher professional identity is a comprehensive reflection of teachers’role perception,emotional experiences,and behavioral tendencies towards their profession.It serves as an intrinsic driving force for teachers’p... Teacher professional identity is a comprehensive reflection of teachers’role perception,emotional experiences,and behavioral tendencies towards their profession.It serves as an intrinsic driving force for teachers’professional development and is also a crucial issue in teacher education research.From a global perspective,this study systematically reviews and examines relevant research on the professional identity of international Chinese language teachers(ICLTs).A comparative analysis is conducted between Chinese and foreign scholars’research in terms of theoretical foundations,research subjects,research content,and research methodologies.This comprehensive overview of the current research landscape in this field,along with a summary of existing achievements and identified problems,facilitates the transformation of fragmented research findings on ICLTs’professional identity into a systematic understanding and reveals research gaps.Building upon this foundation,the study proposes future research prospects for the professional identity of ICLTs from aspects such as the construction of a cross-cultural perspective-based teacher professional identity system,the transformation of teacher professional identity in the context of digital transformation,and case studies on ICLTs’professional identity.The aim is to promote high-quality development in both theory and practice of international Chinese language education. 展开更多
关键词 International Chinese language teachers Professional identity Research status Research implications comparative analysis
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Comparative Analysis of Two Heavy to Blizzard Processes in Beijing Area
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作者 Jixiong HUANG 《Meteorological and Environmental Research》 2025年第1期31-36,共6页
This paper conducted a more comprehensive review and comparative analysis of the two heavy to blizzard processes that occurred in the Beijing area during December 13-15,2023,and February 20-21,2024,in terms of compreh... This paper conducted a more comprehensive review and comparative analysis of the two heavy to blizzard processes that occurred in the Beijing area during December 13-15,2023,and February 20-21,2024,in terms of comprehensive weather situation diagnosis,forecasting,and decision-making services,and summarized the meteorological service support experience of such heavy snow weather processes.It was found that both blizzard processes were jointly influenced by the 700 hPa southwesterly warm and humid jet stream and the near-surface easterly backflow;the numerical forecast was relatively accurate in the overall description of the snowfall process,and the forecast bias of the position of the 700 hPa southwesterly warm and humid jet stream determined the bias of the snowfall magnitude forecast at a certain point;when a deviation was found between the actual snowfall and the forecast,the cause should be analyzed in a timely manner,and the warning and forecast conclusions should be updated.With the full cooperation of relevant departments,it can greatly make up for the deviation of the early forecast snowfall amount,and ensure the safety and efficiency of people's travel. 展开更多
关键词 Heavy to blizzard process Weather situation diagnosis Forecasting and decision-making services Review comparative analysis
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Spatial Characteristic Analysis of the Comparative Advantage of Watermelon and Melon Production in Hainan Province 被引量:2
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作者 柳唐镜 张棵 +3 位作者 别之龙 许勇 李劲松 孔秋生 《Agricultural Science & Technology》 CAS 2013年第4期582-588,605,共8页
[Objective] This study investigated the spatial characteristics of counties (cities) with comparative advantages in watermelon and melon production to provide reference bases in formulating strategies for the develo... [Objective] This study investigated the spatial characteristics of counties (cities) with comparative advantages in watermelon and melon production to provide reference bases in formulating strategies for the development of watermelon and melon industries in Hainan Province. [Method] By using the sowing area, total yield, and yield per unit area of watermelon and melon in Hainan Province as research u- nits, the yield comparative advantage (YCA), efficiency comparative advantage (E- CA), scale comparative advantage (SCA), concentration ratio comparative advantage (CRCA), comprehensive comparative advantage (CCA), ratio of yield per unit area (RYPA), sowing area ratio (SAR), and distribution characteristics of watermelon and melon were systematically analyzed. By referring to the agricultural statistic data of 18 counties (cities) in Hainan Province, indexes for each research unit (i.e., the YCA index, ECA index, SCA index, CRCA index, CCA index, RYPA index, and SAR index) were established and calculated to determine the comparative advantage of watermelon and melon production in Hainan Province. A spatial expression of the research result on a map was conducted by using GIS software. [Result] Seven counties (cities) exhibited comparative advantages in watermelon production, namely, Lingshui, Wanning, Wenchang, Dongfang, Sanya, Ledong, and Changjiang. The Eastern and Southern Hainan Provinces had CCAs, and the Western and Northern Hainan Provinces could be reserved for future development. For melon production, four counties (cities) exhibited comparative advantages, namely, Ledong, Lingshui, Sanya, and Dongfang. The Southern Hainan Province had CCA, whereas the West- ern Hainan Province could be reserved for later development. [Conclusion] The result has showed that establishing watermelon and melon as dominant agricultural prod- ucts is necessary for the future development of the industry and for the formulation of a layout of regions with advantages, where key support and construction should be provided preferentially with the aim to raise the yield, quality, and market com- petitiveness of products. 展开更多
关键词 WATERMELON MELON comparative advantage Spatial analysis Hainan Province
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Comparative Analysis on Fruit Qualities of 7 Litchi Varieties from Vietnam 被引量:1
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作者 张晓芳 刘光华 +5 位作者 罗心平 黄家雄 吕玉兰 娄予强 Nguyen Dinh Tue Tran Mihn Hoa 《Agricultural Science & Technology》 CAS 2010年第8期110-113,共4页
[Objective] The aim was to screen litchi varieties suitable for local production in Vietnam. [Method] The fruit botanical and quality characteristics of the seven litchi varieties introduced into Northern Mountainous ... [Objective] The aim was to screen litchi varieties suitable for local production in Vietnam. [Method] The fruit botanical and quality characteristics of the seven litchi varieties introduced into Northern Mountainous Agriculture and Forestry Science Institute of Vietnam Academy of Agriculture Sciences were compared and analyzed. [Result] Three varieties with good general qualities including Lai Phu Ho,Thach Binh and Hung Long which were suitable to be cultivated in the local area were selected. In addition,Phu Dong was the available,early-maturing germplasm resource. [Conclusion] This research will provide reference for litchi production and breeding in northern mountainous area. 展开更多
关键词 Vietnam litchi comparative analysis of fruit qualities Variety selection
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Comparative Analysis on Fruit Qualities of Longan Varieties form Vietnam 被引量:1
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作者 张晓芳 罗心平 +4 位作者 刘光华 黄家雄 张惠云 NGUYEN Dinh Tue TRAN Mihn Hoa 《Agricultural Science & Technology》 CAS 2011年第10期1461-1463,共3页
[Objective] The aim was to screen longan varieties suitable for local production in Vietnam.[Method] The fruit botanical characteristics and quality characteristics of longan varieties introduced into Northern Mountai... [Objective] The aim was to screen longan varieties suitable for local production in Vietnam.[Method] The fruit botanical characteristics and quality characteristics of longan varieties introduced into Northern Mountainous Agriculture and Forestry Science Institute of Vietnam Academy of Agriculture Sciences were compared and analyzed.[Result] Two varieties with good general qualities including PMP6 and PHS1-1 which were suitable to be cultivated in the local area were selected.In addition,Phu Dong was the available processed germplasm resource.[Conclusion] This research will provide reference for longan production and breeding in Northern Mountainous. 展开更多
关键词 Vietnam longan comparative analysis of fruit qualities Variety selection
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Comparative Analysis of Improving Effects of 12 Maize Populations with Improved S_1 Selection Method
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作者 孙峰成 冯勇 +6 位作者 付增娟 苏二虎 张来厚 赵瑞霞 刘志雄 石海波 李美娜 《Agricultural Science & Technology》 CAS 2014年第10期1687-1692,1713,共7页
ln this study, 12 maize populations were improved with the improved S1 selection method, aiming to increase the improvement efficiency of maize popula-tions. The results showed that number of rows per spike, number of... ln this study, 12 maize populations were improved with the improved S1 selection method, aiming to increase the improvement efficiency of maize popula-tions. The results showed that number of rows per spike, number of grains per row and 100-grain weight were the three important component traits of maize yield. The highest genetic increment was found in Mengqun 2, fol owed by Mengqun 4, Mengqun 1 and other 7 maize populations. Negative genetic increment was shown in Mengqun 3 and 3 introduced foreign maize populations. Some changes were shown in spikes, plant traits and genetic diversity of maize populations. Based on our results, we concluded that Mengqun 2, Mengqun 4, Zhongzong 7, Mengqun C and Mengqun A could be directly used for the line breeding by selfing for their higher genetic increment of yield and better improvement effects of other agricultural traits. Compared with these 5 populations, the improvement potential of other maize populations was limited for their lower genetic increment. 展开更多
关键词 lmproved S1 selection method Maize population Genetic gain comparative analysis
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Heavy metal risks and policy analysis on using industrial waste salts for making value-added snow-melting agents
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作者 Yubiao Ma Jiaxin Yin +2 位作者 Yunfei Wang Lei Wang Jianxin Zhu 《Journal of Environmental Sciences》 2026年第1期756-766,共11页
Industrial waste salts are commonly used to make value-added snow-melting agents to ensure traffic safety in northern China during winter and spring after snowfall.However,heavy metals in industrial waste salts may po... Industrial waste salts are commonly used to make value-added snow-melting agents to ensure traffic safety in northern China during winter and spring after snowfall.However,heavy metals in industrial waste salts may pose certain environmental risks.Snow-melting agents and snow samples were collected and analyzed from highways,arterial roads,footbridges,and other locations in Beijing after the snowstorm in December 2023.It was found that the main component of snow-melting agents was sodium chloride with high concentrations of Cu,Mn,and Zn,which are not regulated in the current policies,despite the recent promotion of environmentally friendly snow-melting agents.The Pb,Zn and Cr contents of some snow samples exceeded the limitation value of surface water quality standards,potentially affecting the soil and water environment near roadsides,although the snow-melting agents comply with relevant standards,which indicates the policy gap in the management of recycled industrial salts.We reviewed and analyzed the relevant standards for snow-melting agents and industrial waste salts proposed nationally and internationally over the past 30 years.Through comparative analysis,we proposed relevant policy recommendations to the existing quality standards of snow-melting agents and the management regulations of industrial waste salts,and the formulation of corresponding usage strategies,aimed at reducing the potential environmental release of heavy metals from the use of snow-melting agents,thereby promoting more sustainable green urban development and environmentally sound waste management. 展开更多
关键词 Snow-melting agent Heavy metals Industrial waste salts recycled comparative analysis
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A Comparative Analysis of Casual Conversation and Institutional Talk
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作者 王柯芦 《疯狂英语(教师版)》 2014年第1期139-147,共9页
This article reflects on the process of transcribing spoken interaction and makes a comparative analysis of two different varieties of spoken interaction(casual conver- sation and institutional talk). By doing so, it ... This article reflects on the process of transcribing spoken interaction and makes a comparative analysis of two different varieties of spoken interaction(casual conver- sation and institutional talk). By doing so, it reveals how the different purposes of speech result in their distinctive characteristics, and shows how language is struc- tured to construct ideational meanings(Field) and interpersonal meanings(Tenor) that define each context. 展开更多
关键词 TRANSCRIPTION comparative analysis casual CONVERSATION INSTITUTIONAL TALK
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A Comparative Analysis of the Chloroplast Genomes of Four Salvia Medicinal Plants 被引量:11
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作者 Conglian Liang Lei Wang +11 位作者 Juan Lei Baozhong Duan Weisi Ma Shuiming Xiao Haijun Qi Zhen Wang Yaoqi Liu Xiaofeng Shen Shuai Guo Haoyu Hu Jiang Xu Shilin Chen 《Engineering》 SCIE EI 2019年第5期907-915,共9页
Herbgenomics is an emerging field of traditional Chinese medicine(TCM)research and development.By combining TCM research with genomics,herbgenomics can help to establish the scientific validity of TCM and bring it int... Herbgenomics is an emerging field of traditional Chinese medicine(TCM)research and development.By combining TCM research with genomics,herbgenomics can help to establish the scientific validity of TCM and bring it into wider usage within the field of medicine.Salvia Linn.(S.Linn.)is a large genus of Labiatae that includes important medicinal plants.In this herbgenomics study,the complete chloroplast(cp)genomes of two Salvia spp.—namely,S.przewalskii and S.bulleyana,which are used as a surrogate for S.miltiorrhiza—were sequenced and compared with those of two other reported Salvia spp.—namely,S.miltiorrhiza and S.japonica.The genome organization,gene number,type,and repeat sequences were compared.The annotation results showed that both Salvia plants contain 114 unique genes,including 80 protein-coding,30 transfer RNA(tRNA),and four ribosomal RNA(rRNA)genes.Repeat sequence analysis revealed 21 forward and 22 palindromic sequences in both Salvia cp genomes,and 17 and 21 tandem repeats in S.przewalskii and S.bulleyana,respectively.A synteny comparison of the Salvia spp.cp genomes showed a high degree of sequence similarity in the coding regions and a relatively high divergence of the intergenic spacers.Pairwise alignment and single-nucleotide polymorphism(SNP)analyses found some candidate fragments to identify Salvia spp.,such as the intergenic region of the trnV–ndhC,trnQ–rps16,atpI–atpH,psbA–ycf3,ycf1,rpoC2,ndhF,matK,rpoB,rpoA,and accD genes.All of the results—including the repeat sequences and SNP sites,the inverted repeat(IR)region border,and the phylogenetic analysis—showed that S.przewalskii and S.bulleyana are extremely similar from a genetic standpoint.The cp genome sequences of the two Salvia spp.reported here will pave the way for breeding,species identification,phylogenetic evolution,and cp genetic engineering studies of Salvia medicinal plants. 展开更多
关键词 SALVIA CHLOROPLAST GENOME comparative analysis
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Comparative Analysis of Nutrient Composition of Caulerpa lentillifera from Different Regions 被引量:9
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作者 ZHANG Meijian MA Yurong +4 位作者 CHE Xinyi HUANG Zumei CHEN Peng XIA Guanghua ZHAO Meihui 《Journal of Ocean University of China》 SCIE CAS CSCD 2020年第2期439-445,共7页
This study investigated the difference of nutrient composition in Caulerpa lentillifera collected from different regions.The nutrient compositions of C.lentillifera from China's Hainan and Shandong provinces were ... This study investigated the difference of nutrient composition in Caulerpa lentillifera collected from different regions.The nutrient compositions of C.lentillifera from China's Hainan and Shandong provinces were determined and compared with those from Semporna(Malaysia),Sabah(Malaysia),Petchburi(Thailand),and two other species of seaweeds(Malaysia).The results showed that the polysaccharide and protein contents of C.lentillifera from Hainan(44.82%±0.98%and 12.5%±0.70%),Shandong(43.22%±1.42%and 14.7%±0.72%),Petchburi(59.27%±2.31%and 12.49%±0.30%),and Sabah(44.02%±2.01%and 19.38%±1.48%)were higher than those of Eucheuma cottonii(26.49%±3.01%and 9.76%±1.33%)and Sargassum polycystum(33.49%±1.70%and 5.40%±0.07%),respectively.The polyunsaturated fatty acid contents in C.lentillifera from Hainan(29.98%)and Shandong(22.11%)were higher than that in Semporna(16.76%±0.27%),Sabah(9.49%),and S.polycystum(20.34%±0.43%),but lower than that in E.cottonii(51.55%±0.57%).In Caulerpa lentillifera of Hainan and Shandong provinces,the essential amino acid(EAA)/total amino acid(TAA)ratios were 35.22%and 38.78%,respectively;and the EAA/ETAA ratios were 54.36%and 63.35%,respectively.The EAA composition of C.lentillifera was close to the ideal model of Food and Agriculture Organization/World Health Organization.C.lentillifera was rich in mineral elements,including calcium((3315.85±127.55)mg(100 g)^-1 and(3728.35±92.38)mg(100 g)^-1),magnesium((6715.74±82.58)mg(100 g)^-1 and(8128.59±242.72)mg(100 g)^-1),and trace elements,including iron((510.65±5.47)mg(100 g)^-1 and(1972.97±183.35)mg(100 g)^-1),selenium((1.04±0.08)mg(100 g)^-1 and(0.83±0.15)mg(100 g)^-1),and zinc((33.90±0.13)mg(100 g)^-1 and(11.75±2.05)mg(100 g)^-1).These results showed that C.lentillifera was more nutritious than S.polycystum or E.cottonii in terms of polysaccharide,protein,and fatty acid contents.Furthermore,both C.lentillifera species collected from Hainan and Shandong provinces show more basic nutrients.Therefore,C.lentillifera has important development and application prospects. 展开更多
关键词 Caulerpa lentillifera nutrient composition fatty acid amino acid MINERAL comparative analysis
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A Comparative Analysis of Evaporate Sediments on Earth and Mars: Implications for the Climate Change on Mars 被引量:8
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作者 ZHENG Mianping KONG Weigang +2 位作者 ZHANG Xuefei CHEN Wenxi KONG Fanjing 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2013年第3期885-897,共13页
The knowledge of Martian salts has gone through substantial changes during the past decades. In the 70th of last century, Viking landers have noticed the existence of salts on Mars. Several salt species have been sugg... The knowledge of Martian salts has gone through substantial changes during the past decades. In the 70th of last century, Viking landers have noticed the existence of salts on Mars. Several salt species have been suggested from then on, such as sulfates and chlorides. However, their origin was a mystery due to the lack of observations. The recent explorations and related studies at the beginning of this century revealed that the crustal composition of Mars is similar to that of Earth, and it was hypothesized that almost one third of Martian surface was covered by oceans and lakes in the early stage of Mars. The huge water bodies may have dissolved a large quantity of ions from Martian primary rocks during the whole Noachian and Hesperian epoch. After the enormous drought event happened during the late Hesperian and the early Amazonian, these dissolved ions have formed huge salts deposits and most of them were preserved on Mars until today. To date, carbonates, sulfates, chlorides have all been detected by orbital remote sensing and by landers and rovers. However, the salt mineral assemblages on Mars seems to have some differences from those on Earth, e.g., rich in sulfates and lack of massive carbonates. To explain this difference, we propose that most of the surface carbonates precipitated from the ancient oceans may have been dissolved by the later ubiquitous acidic fluids originated from the global volcanism in the Hesperian era, and formed the enormous sulfate deposits as detected, and this hypothesis seems to be supported by the evidence that most of the sulfate deposits distribute around the Tharsis volcanic province while the survived carbonates located far from it. This process can release most of the carbon on Mars to the atmosphere in the form of CO2 and then be erased by the late heavy bombardments, which might have profound influence on the climate change happened in the Hesperian age. The positive correlation between the GRS results of the potassium distributions and the distribution of chlorides on Mars, together with the high Br concentration measured from the evaporate sediments at two Mars exploration rover landing sites, indicate that the brines in the regions where the chlorides deposited may have reached the stage for potassium salts deposition, thus we propose for the first time that potassium salts deposits might be prevalent in these regions. 展开更多
关键词 MARS evaporate sediments comparative analysis climate change potassium salts deposition
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Comparative analysis of rapamycin biosynthesis clusters between Actinoplanes sp. N902-109 and Streptomyces hygroscopicus ATCC29253 被引量:5
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作者 HUANG He REN Shuang-Xi +1 位作者 YANG Sheng HU Hai-Feng 《Chinese Journal of Natural Medicines》 SCIE CAS CSCD 2015年第2期90-98,共9页
The present study was designed to identify the difference between two rapamycin biosynthetic gene clusters from Streptomyces hygroscopicus ATCC29253 and Actinoplanes sp. N902-109 by comparing the sequence and organiza... The present study was designed to identify the difference between two rapamycin biosynthetic gene clusters from Streptomyces hygroscopicus ATCC29253 and Actinoplanes sp. N902-109 by comparing the sequence and organization of the gene clusters. The biosynthetic gene cluster for rapamycin in Streptomyces hygroscopicus ATCC29253 was reported in 1995. The second rapamycin producer, Actinoplanes sp. N902-109, which was isolated in 1995, could produce more rapamycin than Streptomyces hygroscopicus ATCC29253. The genomic map of Actinoplanes sp. N902-109 has been elucidated in our laboratory. Two gene clusters were compared using the online software anti-SMASH, Glimmer 3.02 and Subsystem Technology(RAST). Comparative analysis revealed that the organization of the multifunctional polyketide synthases(PKS) genes: Rap A, RapB, RapC, and NRPS-like RapP were identical in the two clusters. The genes responsible for precursor synthesis and macrolactone modification flanked the PKS core region in N902-109, while the homologs of those genes located downstream of the PKS core region in ATCC29253. Besides, no homolog of the gene encoding a putative type II thioesterase that may serve as a PKS "editing" enzyme accounted for over-production of rapamycin in N902-109, was found in ATCC29253. Furthermore, no homologs of genes rapQ(encoding a methyltransferase) and rap G in N902-109 were found in ATCC29253, however, an extra rap M gene encoding methyltransferase was discovered in ATCC29253. Two rapamycin biosynthetic gene clusters displayed overall high homology as well as some differences in gene organization and functions. 展开更多
关键词 RAPAMYCIN ACTINOPLANES Biosynthetic gene cluster comparative analysis
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Comparative analysis of chemical components between barks and leaves of Eucommia ulmoides Oliver 被引量:10
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作者 周菊峰 张泰铭 +1 位作者 陈望爱 梁逸曾 《Journal of Central South University》 SCIE EI CAS 2009年第3期371-379,共9页
The chemical components of the essential oils in the barks and leaves of Eucommia ulmoides Oliver were analyzed and compared by chromatograms and mass spectra technique, heuristic evolving latent projections (HELP), a... The chemical components of the essential oils in the barks and leaves of Eucommia ulmoides Oliver were analyzed and compared by chromatograms and mass spectra technique, heuristic evolving latent projections (HELP), alternative moving window factor analysis (AMWFA) algorithms and normalization method based on the peak areas; the flavones in the barks and leaves of Eucommia ulmoides Oliver were separated on an ODS column by gradient elution carried out with the flow phase consisting of water, methanol and phosphoric acid (0.1%), and their contents were quantitatively determined by standard curve method and diode array detection (DAD) at 362 nm. The results show that 68 and 73 compounds respectively from essential oils of the barks and leaves of Eucommia ulmoides Oliver are identified, and there are 33 mutual compounds among 108 compounds determined. The total contents of these volatile components of the two samples possess 92.9% and 97.75% of the gross of the relevant essential oils, respectively; the contents of the rutin, quercetin and kaempferol in the barks and leaves of Eucommia ulmoides Oliver are 0.016 9, 0.003 6, 0.002 1 and 0.064 4, 0.030 2, 0.010 0 mg/g, respectively, and the determination recoveries are 95.2%-106.2%. The comparative analysis shows that for the barks and leaves of Eucommia ulmoides Oliver, there are significant differences in their components of the relevant essential oils and flavones. 展开更多
关键词 couple chromatography chemometric algorithm comparative analysis essential oil FLAVONE Eucommia ulmoides Oliver
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Comparative Analysis of the Multi-Frequency Bio-impedance and Dual-energy X-ray Absorptiometry on Body Composition in Obese Subjects 被引量:5
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作者 WANG Zheng He YANG Zhong Ping +2 位作者 WANG Xi Jie DONG Yan Hui MA Jun 《Biomedical and Environmental Sciences》 SCIE CAS CSCD 2018年第1期72-75,共4页
To examine accuracy of body composition predicted by the Multi-Frequency Bioelectric Impedance Analysis (MF-BIA) compared with the Dual-energy X-ray Absorptiometry (DXA) in adults with obese. We measured body comp... To examine accuracy of body composition predicted by the Multi-Frequency Bioelectric Impedance Analysis (MF-BIA) compared with the Dual-energy X-ray Absorptiometry (DXA) in adults with obese. We measured body composition of 749 adults with obese both by the MF-BIA and DXA. The Lin's concordance correlation and the Bland-Altman plots were used to examine the consistency. The concordance correlation coefficient of %BF between the MF-BIA and DXA in men and women was 0.560, and 0.669, respectively. Compared with the DXA, the MF-BIA significantly underestimated %BF by 4.33% in men (P 〈 0.001), however overestimated %BF by 0.50% in women (P 〈 0.001). After corrected by the correction equations established in this study, the differences were significantly decreased. Therefore, the MF-BIA (TANITA MC-180) may need to be corrected in estimating body composition for adults with obese. 展开更多
关键词 comparative analysis Dual-energy X-ray Absorptiometry on Body
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Natural Heritage Value of Xinjiang Tianshan and Global Comparative Analysis 被引量:6
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作者 XU Xiaoliang YANG Zhaoping +2 位作者 Adayi Saiken Shao Rui LIU Xinyu 《Journal of Mountain Science》 SCIE CSCD 2012年第2期262-273,共12页
Xinjiang Tianshan is a serial natural property that has been nominated for World Heritage status.This paper presents a systematically comprehensive and comparative analysis of the heritage resources of Xinjiang Tiansh... Xinjiang Tianshan is a serial natural property that has been nominated for World Heritage status.This paper presents a systematically comprehensive and comparative analysis of the heritage resources of Xinjiang Tianshan according to the World Heritage criteria.Its biological,ecological and aesthetic values,which are of global importance, are documented.It is concluded that Xinjiang Tianshan meets the world heritage criteria(vii)and (ix).Xinjiang Tianshan is compared with other mountain world heritage sites,mountains in Central Asia,the Tianshan Mountains outside China,and with the protected areas of the Tianshan Mountains on the Tentative List for World Heritage Sites,so as to provide objective data for the world heritage application. 展开更多
关键词 Xinjiang Tianshan Natural Heritage Heritage characteristics Heritage values comparative analysis
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Structural characterization and comparative analysis of the chloroplast genome of Ginkgo biloba and other gymnosperms 被引量:3
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作者 Xiaoming Yang Tingting Zhou +4 位作者 Xiya Su Guibin Wang Xuhui Zhang Qirong Guo Fuliang Cao 《Journal of Forestry Research》 SCIE CAS CSCD 2021年第2期765-778,共14页
Ginkgo biloba is a famous living“fossil”and has played an important role in the evolution of the Plant Kingdom.Here,the complete chloroplast genome of G.biloba was sequenced and analysed.The chloroplast genome was 1... Ginkgo biloba is a famous living“fossil”and has played an important role in the evolution of the Plant Kingdom.Here,the complete chloroplast genome of G.biloba was sequenced and analysed.The chloroplast genome was 156,990 bp long and predicted to encode 134 genes including 85 protein-coding genes,41 tRNA genes and 8 rRNA genes.The chloroplast genome has a typical quadripartite structure with a pair of inverted repeat regions(IRa and IRb,17,732 bp),a large(LSC,99,259 bp)and small single(SSC,22,267 bp)copy region.After an extensive comparison to previously published gymnosperm plastomes,the gene content and organisation of G.biloba showed high divergence,although part was relatively conserved.The two typical IR regions in the G.biloba chloroplast genome were relatively shorter because it the ycf2 gene.In addition,it was obvious that the IR regions and gene loss were responsible for changes in chloroplast genome size and structure stability,which influenced plastome evolution in different gymnosperms.Phylogenetic analysis revealed that G.biloba is sister to cycads rather than to gnetophytes,cupressophytes,and Pinaceae.Overall,the study showed that the genomic characteristics of G.biloba would be of great help in the further research on the taxonomy,species identification and evolutionary history of gymnosperms,especially for their position in plant systematics and evolution. 展开更多
关键词 Ginkgo biloba Chloroplast genome comparative analysis PHYLOGENY
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Comparative Genomic Analysis of Enterovirus 71 Revealed Six New Potential Neurovirulence-associated Sites 被引量:6
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作者 JIA Qing Jun CHEN Xin Yu +4 位作者 LI De Zhou XU Juan Juan XU Zhi Gang DUAN Zhi Liang WEN Jin Sheng 《Biomedical and Environmental Sciences》 SCIE CAS CSCD 2016年第10期767-772,共6页
In the present study,the complete genomes of four common(4/EV71/Wenzhou/CHN/2014,15/EV71/Wenzhou/CHN/2014,116/EV71/Wenzhou/CHN/2014,and 120/EV71/Wenzhou/CHN/2014)and two virulent(11/EV71/Wenzhou/CHN/2014and 109/EV7... In the present study,the complete genomes of four common(4/EV71/Wenzhou/CHN/2014,15/EV71/Wenzhou/CHN/2014,116/EV71/Wenzhou/CHN/2014,and 120/EV71/Wenzhou/CHN/2014)and two virulent(11/EV71/Wenzhou/CHN/2014and 109/EV71/Wenzhou/CHN/2014)enterovirus 71(EV71)isolates were sequenced and described.They are 7405 bp in length and belong to EV71 sub-genotype C4 (C4a cluster). 展开更多
关键词 CHN UTR EV comparative Genomic analysis of Enterovirus 71 Revealed Six New Potential Neurovirulence-associated Sites
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