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A Comparative Analysis of the New -3(-n) - 1 Remer Conjecture and a Proof of the 3n + 1 Collatz Conjecture
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作者 Mike Remer 《Journal of Applied Mathematics and Physics》 2023年第8期2216-2220,共5页
This scientific paper is a comparative analysis of two mathematical conjectures. The newly proposed -3(-n) - 1 Remer conjecture and how it is related to and a proof of the more well known 3n + 1 Collatz conjecture. An... This scientific paper is a comparative analysis of two mathematical conjectures. The newly proposed -3(-n) - 1 Remer conjecture and how it is related to and a proof of the more well known 3n + 1 Collatz conjecture. An overview of both conjectures and their respective iterative processes will be presented. Showcasing their unique properties and behavior to each other. Through a detailed comparison, we highlight the similarities and differences between these two conjectures and discuss their significance in the field of mathematics. And how they prove each other to be true. 展开更多
关键词 -3(-n) - 1 Remer Conjecture 3n + 1 Collatz Conjecture comparative analysis PROOF Natural Numbers Integer Sequences Factorial Processes Par-tial Differential Equations Bounded Values Collatz Conjecture Collatz Algo-rithm Collatz Operator Collatz Compliance And Mathematical Conjectures
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Comparative Analysis of Rice Export Competitiveness in Heilongjiang Province of China Based on Index Method
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作者 Min LU Yafei GUO 《Asian Agricultural Research》 2023年第6期14-20,共7页
Based on the analysis of rice planting and export development in Heilongjiang Province in 2013-2021,this paper comprehensively used three export competitiveness analysis methods,namely,trade competitiveness index,reve... Based on the analysis of rice planting and export development in Heilongjiang Province in 2013-2021,this paper comprehensively used three export competitiveness analysis methods,namely,trade competitiveness index,revealed comparative advantage(RCA)analysis and international market share analysis,to compare the four major rice exporters in the world and the three major rice export provinces and cities in China.Besides,it evaluated the rice export competitiveness of Heilongjiang Province from multiple perspectives.It analyzed the reasons for low competitiveness in terms of export product structure,export market structure,production and processing technology,and brand building.Finally,it is recommended to clarify the positioning of rice export quality and take more measures to ensure product quality;improve the level of industrialization of rice production and processing,and extend the rice industry chain;develop diversified rice export markets and improve export flexibility;adhere to the principle of"opening the door and going out",expand the international popularity of high-quality brands,so as to enhance the rice export competitiveness of Heilongjiang Province. 展开更多
关键词 RICE Export competitiveness Trade competitiveness index Revealed comparative advantage(RCA)analysis International market share 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 Nutrient Composition of Caulerpa lentillifera from Different Regions 被引量:8
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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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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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Structural characterization and comparative analysis of the chloroplast genome of Ginkgo biloba and other gymnosperms 被引量:2
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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 Analysis on Farmers' Specialized Cooperatives from the Perspective of Agricultural Industry Chain 被引量:3
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作者 Guangmi LU Zaiqing ZHU 《Asian Agricultural Research》 2017年第2期6-9,11,共5页
Taking three typical farmers' specialized cooperatives in Jingyuan County of Gansu Province as example,this paper compared with the operating mode of three cooperatives and their position in the agricultural indus... Taking three typical farmers' specialized cooperatives in Jingyuan County of Gansu Province as example,this paper compared with the operating mode of three cooperatives and their position in the agricultural industry chain,and analyzed operating characteristics,problems,and similarities of three cooperatives and their functions in the agricultural industry chain.The study indicated that the farmers' specialized cooperatives can accurately find their position in the agricultural industry chain.This is helpful for raising their comprehensive competitiveness and it is very important to manage the survival and development of farmers' specialized cooperatives,which is of utmost importance to their effective operation.According to this study,the government should strengthen its support,speed up the cultivation of new-type professional farmers,while farmers' specialized cooperatives should grasp the operating characteristics,locate themselves and integrate multi-resources.These are effective measures for promoting healthy operation of farmers' specialized cooperatives. 展开更多
关键词 Farmers’ specialized cooperatives Operating mode Agricultural industry chain comparative analysis
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Comparative analysis of the complete chloroplast genomes of six white oaks with high ecological amplitude in China 被引量:1
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作者 Xue Liu Ermei Chang +1 位作者 Jianfeng Liu Zeping Jiang 《Journal of Forestry Research》 SCIE CAS CSCD 2021年第5期2203-2218,共16页
Quercus L.has significant societal,ecological and economic benefits in the Northern Hemisphere.However,species identification among oaks is notoriously difficult.China harbours highly diverse oaks,of which the diversi... Quercus L.has significant societal,ecological and economic benefits in the Northern Hemisphere.However,species identification among oaks is notoriously difficult.China harbours highly diverse oaks,of which the diversity of white oaks is the most extensive;however,to date,the evolution of chloroplast(cp)genomes in white oaks in China has not been comprehensively studied.Thus,we sequenced the complete cp genomes(161,254 bp,161,229 bp and 161,254 bp in size)of three white oak species(Quercus serrata Thunb.var.brevipetiolata A.DC.Nakai,Quercus wutaishansea Mary and Quercus mongolica Fischer ex Ledebour,respectively).Six white oak species(Quercus aliena Blume,Quercus dentata Thunb.,Quercus aliena Blume var.acutiserrata Maximowicz ex Wenzig,Q.serrata var.brevipetiolata,Q.wutaishanica and Q.mongolica)and five other Fagaceae species(Quercus rubra L.,Quercus variabilis Bl.,Quercus aquifolioid.es Rehd.et Wils.,Fagus engleriana Seem.and Castanea henryi Skan Rehd.et Wils.)were retrieved for comparative analyses.We detected11 highly divergent regions(psbA,matK/rps16,rps16,trnSGCU/trnG-GCC,trnR-UCU/atpA,trnT-GGU/psbD,ndhJ,ndhJ/ndhK,accD,ndhF and ycfl)through comparative analyses and these regions might be used as molecular markers.Theωratio of the rps12,rpoC2 and ycf1 genes was greater than 1 in several comparison groups between white oaks and the petA gene was subjected to significant positive selection between the comparison of six white oaks and Q.variabilis.Phylogenetic analyses revealed that six white oaks were grouped with Q.rubra,forming a single clade. 展开更多
关键词 White oaks China Plastid genome comparative analysis Positive selection petA
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Comparative Analysis of Gene Expression in Two Muskmelon Cultivars(Cucumis melo L.) Under Salt Stress 被引量:1
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作者 WEI Shi-wei ZHANG Fu-rong +3 位作者 ZHANG Yi-dong WANG Li-min CHEN Jia-bei HUANG Dan-feng 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2014年第10期2132-2140,共9页
Salinity is one of the most important abiotic stresses that adversely affects crop growth and productivity. A subtractive suppression hybridization (SSH) library were constructed from the roots of salt-sensitive Yul... Salinity is one of the most important abiotic stresses that adversely affects crop growth and productivity. A subtractive suppression hybridization (SSH) library were constructed from the roots of salt-sensitive Yulu cultivar melon seedlings under salt stress; 557 high-quality expressed sequence tags (ESTs) were randomly sequenced, with an average size of 428 bp, which assembled into 68 contigs and 315 singletons. Compared with our previous SSH library generated from the salt-tolerant Bingxuecui cultivar, the proportion of transcripts involved in metabolism, protein fate, cellular communication/signal transduction mechanisms, and cell rescue/defense were 4, 1.46, 0.94, and 0.4% higher, respectively, in the salt-tolerant cultivar than the in salt-sensitive cultivar. Quantitative real-time PCR analysis of eleven transcripts revealed temporal variations in their expression in the two cultivars under salt stress. One NAC gene (JZ477011) was heterologously expressed in yeast for functional characterization, and enhanced the sensitivity of yeast cells to high-salinity to salt stress and inhibited their growth. Information regards to their functions would aid in the understanding of response mechanisms to saline stress and in the development of molecular markers for selecting salt-tolerant melon cultivars. 展开更多
关键词 comparative analysis functional characterization gene expression salt stress SSH melon cultivars
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Energy Theft Detection in Smart Grids:Taxonomy,Comparative Analysis,Challenges,and Future Research Directions 被引量:1
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作者 Mohsin Ahmed Abid Khan +4 位作者 Mansoor Ahmed Mouzna Tahir Gwanggil Jeon Giancarlo Fortino Francesco Piccialli 《IEEE/CAA Journal of Automatica Sinica》 SCIE EI CSCD 2022年第4期578-600,共23页
Electricity theft is one of the major issues in developing countries which is affecting their economy badly.Especially with the introduction of emerging technologies,this issue became more complicated.Though many new ... Electricity theft is one of the major issues in developing countries which is affecting their economy badly.Especially with the introduction of emerging technologies,this issue became more complicated.Though many new energy theft detection(ETD)techniques have been proposed by utilising different data mining(DM)techniques,state&network(S&N)based techniques,and game theory(GT)techniques.Here,a detailed survey is presented where many state-of-the-art ETD techniques are studied and analysed for their strengths and limitations.Three levels of taxonomy are presented to classify state-of-the-art ETD techniques.Different types and ways of energy theft and their consequences are studied and summarised and different parameters to benchmark the performance of proposed techniques are extracted from literature.The challenges of different ETD techniques and their mitigation are suggested for future work.It is observed that the literature on ETD lacks knowledge management techniques that can be more effective,not only for ETD but also for theft tracking.This can help in the prevention of energy theft,in the future,as well as for ETD. 展开更多
关键词 CHALLENGES comparative analysis energy theft detection future research directions smart grid TAXONOMY
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A Comparative Analysis of Primary and Extreme Characteristics of Dry or Wet Status between Asia and North America 被引量:1
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作者 华丽娟 马柱国 钟霖浩 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2011年第2期352-362,共11页
In this study, the Palmer Drought Severity Index (PDSI) was used to analyze the average and extreme dry/wet states of Asia and North America from 1953 to 2003. The results indicate that the two continents underwent ... In this study, the Palmer Drought Severity Index (PDSI) was used to analyze the average and extreme dry/wet states of Asia and North America from 1953 to 2003. The results indicate that the two continents underwent drying trends during this period. Compared with North America, Asia showed more severe drought trends. However, more significant and regular seasonal variation for drought was found in North America. The driest regions in Asia were located in the northern region of China, Mongolia, and eastern mid-Siberian plateau. Most regions in central North America were relatively wetter than other regions. The northern and southwestern regions of North America, as well as the Atlantic and Pacific coastal areas, experienced the most drought during this period. A sharp increase of the drought area and the number of extreme drought events took place from 1997 to 2003 in both Asia and North America. Severe drought events were more likely to occur during the summer on both continents. Asia had the most extreme drought events during July, but North America reached its highest drought frequency from June to September. In Asia, a persistent increasing trend of extreme drought emerged throughout the studied period. However, a more complex evolution of drought emerged in North America: a decreasing trend appeared before the mid-1960s and an increasing trend appeared after the late 1970s. A relatively steady dry/wet status was observed between the mid-1960s and the late 1970s. The role of exceptional, extreme drought events with respect to the La Nin?a event was considered during 1997–2003. 展开更多
关键词 mean dry/wet status extreme drought event ASIA North America comparative analysis Palmer Drought Severity Index (PDSI)
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Comparative Analysis of Environment Right and Property Right of Environment Resources 被引量:1
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作者 ZUO Zheng-qiang ZHANG Yong-ren 《Meteorological and Environmental Research》 2012年第5期60-64,共5页
关键词 Environment right Environment resources property right comparative analysis China
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Comparative analysis on transcriptome sequencings of six Sargassum species in China
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作者 WANG Guoliang SUN Jing +8 位作者 LIU Guiming WANG Liang YU Jun LIU Tao CHI Shan LIU Cui GUO Haiyan WANG Xumin WU Shuangxiu 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2014年第2期37-44,共8页
Species of Sargassum are distributed worldwide, and are of great ecological and economic importance in marine ecosystems and bioresources. In this study, transcriptome sequencings of six Sargassum species were perform... Species of Sargassum are distributed worldwide, and are of great ecological and economic importance in marine ecosystems and bioresources. In this study, transcriptome sequencings of six Sargassum species were performed for the first time using an Illumina platform. For each sample, a total of 2.1-2.5 Gb of nucle-otides are collected and assembled into 69 871-116 790 scaffolds, with an average length of 410-550 bp and N50 length of 756-1 462 bp. A total of 20 512-28 684 unigenes of each sample were annotated and compared well with known gene sequences from nr database. Clusters of Orthologous Groups (COG), gene ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) analyses were also performed for further un-derstanding of gene functions and regulation pathways. Gene expression levels were calculated based on RPKM values and compared among these species, especially for those genes related to carbohydrate metab-olism. Cluster analyses indicated that the differences of global gene expression between S. fusiforme, which was nominated as Hizikia fusiformis before, and other five species were not significant. Further phylogenet-ic analysis of 108 orthologous genes confirmed that S. fusiforme had closer relationship with S. hemiphyllum rather than S. horneri. These transcriptome data provided valuable information for better understanding of genome and gene characteristics of Sargassum algae and benefiting comparative and phylogenetic studies of Phaeophyceae species in future studies. 展开更多
关键词 SARGASSUM Sargassum fusiforme transcriptome sequencing comparative analysis
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Physicochemical Properties Comparative Analysis of Corn Starch and Cassava Starch, and Comparative Analysis as Adhesive
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作者 Xiaojian Chen Wenrui Yao +5 位作者 Feifei Gao Dingyuan Zheng Qiong Wang Jun Cao Haiyan Tan Yanhua Zhang 《Journal of Renewable Materials》 SCIE EI 2021年第5期979-992,共14页
The morphology and properties of corn starch and cassava starch were compared by SEM, DSC and TGA. Theeffects of amylose and amylopectin content on starch properties were studied by FT-IR, XRD and XPS. The plywood wa... The morphology and properties of corn starch and cassava starch were compared by SEM, DSC and TGA. Theeffects of amylose and amylopectin content on starch properties were studied by FT-IR, XRD and XPS. The plywood was pressed with the prepared adhesive and the bonding strength of the plywood was tested to analyze thedifference among the adhesives from different plant sources and the difference after blending PAPI prepolymer.FT-IR results showed that the hydroxyl peak of cassava starch was stronger and wider. TGA showed that the residue of cassava starch was lower, but the thermal stability of cassava starch was almost the same. XPS data showedthat the oxygen content of cassava starch was slightly higher, but the carbon content was slightly lower. SEM analysis showed that corn starch granules were more irregular and sharper than cassava starch, and cassava starchgranules were more uniform, regular and round. 展开更多
关键词 Corn starch cassava starch comparative analysis ADHESIVE
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Comparative Analysis of Two Rainstorms in the Southwest of Hunan Province
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作者 LV Xiao-hua DAI Jin +1 位作者 YANG Ke ZHU He-xiang 《Meteorological and Environmental Research》 CAS 2012年第12期20-28,32,共10页
Using NCEP 1° × 1° reanalysis data within 6 h, conventional observational data, data from regional automatic rainfall stations, satellite cloud pictures and Doppler radar data, we compared the physical ... Using NCEP 1° × 1° reanalysis data within 6 h, conventional observational data, data from regional automatic rainfall stations, satellite cloud pictures and Doppler radar data, we compared the physical conditions, dynamic and thermodynamic characteristics of two rainstorms in the southwest of Hunan Province on May 12 and June 15 in 2011. The results showed that the first process was triggered by strong cold air under unstable potential, while the second process was caused by shear line appearing from the east; during the first process, cold air divided into many parts and moved towards south, rainfall was uniform and lasted for a long time, while rainfall was relatively concentrated and strong, and lasted for a short time during the second process; the peak of K index appeared only during the second process; no sign of heavy rainfall was found from satellite cloud pictures and radar echo pictures during the first process, while obvious cloud cluster and echo ribbons could be found from satellite cloud pictures and radar echo pictures during the second process, which were the sign of heavy rainfall; slow movement of echo or little movement resulted in the second rainstorm, and constant echo intensity was the main reason for the occurrence of the second rainstorm. In addition, there was low-level southwest jet during the two processes, which provided favorable conditions for the transportation of water vapor and energy during the two processes. However, there was a great difference between the two rainstorms in the intensity and thickness of low-level jet, that is, the intensity and thickness of low-level jet during the first process were obviously weaker than these during the second process. 展开更多
关键词 RAINSTORM Influence system comparative analysis Water vapor conditions Southwest jet Radar echo China
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Comparative Analysis on Activity Patterns of CG between Lianyungang and Yancheng
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作者 Fang Tian Jie Liu +1 位作者 Ye Ding Chunmei Zhang 《Meteorological and Environmental Research》 CAS 2013年第10期9-13,18,共6页
[Objective] The reseamh aimed to contrast and analyze CG activity rules in Lianyungang and Yancheng. [Method] By using lightning location data, basic characteristics of lightning activities in Lianyungang and Yancheng... [Objective] The reseamh aimed to contrast and analyze CG activity rules in Lianyungang and Yancheng. [Method] By using lightning location data, basic characteristics of lightning activities in Lianyungang and Yancheng both located at the eastem coast of Jiangsu were analyzed and contrasted. [Result] CG characteristics in Uanyungang and Yancheng were same, and negative CG was dominant. Monthly change activity rule of CG basically presented single-peak distribution, and peak value appeared in August. Monthly change of the lightning was drastic, and high- occurrence period was both in summer. Daily change trend of CG in the two sites was consistent. High-occurrence period of the lightning was in af- temoon and early morning, and occurrence frequency of the lightning in the morning was less. Spatial distribution of CG in Lianyungang and Yancheng was very uneven. Lightning activity in Lianyungang mainly concentrated in northwest and southeast areas of Donghai County and western area of Guannan County. Especially in Donghai County, it was the area where lightning strike density was the maximum. Lightning strike activity in Yanchang was more concentrated, and mainly concentrated in the west, namely near Jiangying Town and Louwang Town. Distribution characteris- tics of CG intensities in the two sites were same. Waveform changes of the positive CG in the two sites were slower than that of the negative CG, and current intensity concentrated from + 20 to ~ 50 kA. [ Conclusion ] By contrasting and analyzing lightning activity rules in Lianyungang and Yanchang, we could share and complement data in the two cities better, and serve for routine lightning prevention and early-warning better. 展开更多
关键词 CG Activity rule comparative analysis Lianyungang Yancheng China
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Clinical comparative analysis of the outcomes with a yellow- and a violet-tinted intraocular lens
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作者 Peter Mojzis Zdenek Bombera +3 位作者 Sarka Vesela Daniela Klapuchova Peter Ziak David P.Pinero 《International Journal of Ophthalmology(English edition)》 SCIE CAS 2016年第1期166-169,共4页
Dear Sir,I am Dr. Peter Mojzis from Premium Clinic in Teplice (Czech Republic). I write to present the results of a comparative study of clinical outcomes obtained with two different types of tinted intraocular lens... Dear Sir,I am Dr. Peter Mojzis from Premium Clinic in Teplice (Czech Republic). I write to present the results of a comparative study of clinical outcomes obtained with two different types of tinted intraocular lenses (IOLs), yellow-vs violet-tinted IOLs. IOLs containing a yellow chromophore that filters simultaneously ultra violet (UV) and blue light were developed several years ago in the attempt of avoiding that blue and violet visible light reached the retina in the pseudophakic eye. 展开更多
关键词 IOL and a violet-tinted intraocular lens Clinical comparative analysis of the outcomes with a yellow
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Comparative Analysis of Two Local Heavy Rainstorms in Northwestern Shandong
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作者 ZHU Yi-qing CAO Xing-feng +2 位作者 LIU Ying-jie SUN Chang-zheng HU Shun-qi 《Meteorological and Environmental Research》 CAS 2011年第9期24-27,共4页
[Objective] The aim was to comparatively analyze two local heavy rainstroms in northwestern Shandong Province, China. [Method] Based on the observation data from automatic weather station, sounding data and NCEP reana... [Objective] The aim was to comparatively analyze two local heavy rainstroms in northwestern Shandong Province, China. [Method] Based on the observation data from automatic weather station, sounding data and NCEP reanalysis data, two local heavy rainstorms at night on July 18 and August 9 in 2010 in northwestern Shandong was comparatively analyzed from the aspects of circulation situation, influence system and physical field, and the internal structure and possible formation mechanism of local heavy rain in Shandong were discussed further. [Result] The two rainstorms occurred in the forepart of southwest air in front of 500 hPa trough, and there was stronger atmospheric baroclinicity in the front zone near 850 hPa. The two rainstorms were affected by southwest warm and humid airflow at low level and shear line at 850 hPa; rainstorm often appeared in intensive area behind θse high-energy tongue, and rainstorm area corresponded with the area with high vertical speed well. From the differences, during the first rainstorm, there was obvious southwest low level jet and shear line at 700 hPa, and the area with high precipitation was located in the south of warm shear line at 700 hPa; during the latter rainstorm, there was no obvious southwest low level jet and shear line, and the area with high precipitation was located in the region between two high pressures. [Conclusion] The study could provide valuable thinking for the forecast of this kind of rainstorm in the future. 展开更多
关键词 Local heavy rainstorms Weather process comparative analysis Northwestern Shandong China
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Comparative Analysis of Two Heavy Snow Processes Based on Doppler Radar Radial Velocity
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作者 Yang Shuhua Yang Hai +3 位作者 Du Meiling Qin Yajuan Zhang Yufang Li Laping 《Meteorological and Environmental Research》 CAS 2014年第7期12-16,共5页
By using the data of synoptic charts and Datong Doppler radar data, two heavy snow processes in Datong during November 9 - 10, 2009 and on March 14, 2010 were analyzed. The results show that surface current, occluded ... By using the data of synoptic charts and Datong Doppler radar data, two heavy snow processes in Datong during November 9 - 10, 2009 and on March 14, 2010 were analyzed. The results show that surface current, occluded fronts, high-altitude and low-altitude jet stream were main reasons for the heavy snow processes. Zero velocity curves were like "S" at elevations of 0.5, 1.5 and 2.4~, and there were a pair of" bull's-eye" structure, showing that heavy snow would occur. As for the two heavy snow processes, the qualitative judgment results based on the area of posi- tive and negative velocity zones were consistent with the quantitative analysis results based on the average divergence well, so we can use radar images to judge features of velocity fields rapidly in practice. 展开更多
关键词 Heavy snow Features of radial velocity comparative analysis China
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Comparative Analysis of the Evolution of Community Space in Chengdu-Chongqing Region: A Case Study of Main Urban Areas in Chengdu and Chongqing
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作者 GAO Wei XIAO Yue +12 位作者 HE Yi GUO Zhenni LENG Qinyi LIU Hong KANG Yichen WANG Zhiye ZHU Zeliang WANG Jiamin ZHOU Xu CHAO Yi DONG Hailong MAO Xiao WANG Chensu 《Journal of Landscape Research》 2017年第5期22-26,共5页
Due to the integrated development between Chengdu and Chongqing,there are a large number of residents flowing into the two cities from their surrounding areas,so community renewal is imminent.Because of the similarity... Due to the integrated development between Chengdu and Chongqing,there are a large number of residents flowing into the two cities from their surrounding areas,so community renewal is imminent.Because of the similarity in the historical and cultural background of the two places,a comparative analysis of the evolution of community space in Chengdu-Chongqing Region enables Chengdu and Chongqing learn from each other and speed up the pace of renewal.This paper analyzed the evolution of community space in main urban areas of Chengdu and Chongqing.Specifically,the evolution of community space in Chengdu and Chongqing went through three stages.The starting time of community renewal in the two places was very close,but the duration of each stage varied.The second stage of Chengdu continued for a longer time,so its renovation and renewal of the community space was more detailed and thorough,and the emphasis and extension direction of the evolution of the community space were different.The evolution of community space in both Chengdu and Chongqing went through"mechanical renewal of demolition and construction—small-scale gradual renewal",but the path of renewal and development of the community space in Chengdu was faster.This paper,from the perspective of the evolution of community space,put forward the framework and content of community renewal in Chengdu and Chongqing based on community development and elaborated the community research content based on community development. 展开更多
关键词 Chengdu-Chongqing Region Community space Integrated development comparative analysis
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