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Rice Storage Proteins:Focus on Composition,Distribution,Genetic Improvement and Effects on Rice Quality 被引量:4
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作者 LONG Xinkang GUAN Chunmin +5 位作者 WANG Lin JIA Liting FU Xiangjin LIN Qinlu HUANG Zhengyu LIU Chun 《Rice science》 SCIE CSCD 2023年第3期207-221,I0035-I0037,共18页
Rice storage proteins(RSPs)are plant proteins with high nutritional quality.As the second largest type of storage substance in rice,it is the main source of protein intake for people who consume rice as a staple food.... Rice storage proteins(RSPs)are plant proteins with high nutritional quality.As the second largest type of storage substance in rice,it is the main source of protein intake for people who consume rice as a staple food.The content and type of RSPs affect the appearance,processing quality and eating quality of rice.These effects involve the distribution of RSPs in rice grains as well as the interactions of RSPs with other components such as starch in rice grains.In the past two decades,some progress has been made in the genetic improvement of RSPs.However,the determination mechanism of protein content and composition in rice is still unclear,and the mechanism of the effect of RSPs on rice quality has not been elucidated.In this review,the composition,biosynthesis and distribution of RSPs,and quantitative trait loci mapping and cloning of RSP genes are summarized,the research progress of the influence of RSPs and their components on rice quality are reviewed,and the research directions in the future are proposed. 展开更多
关键词 rice storage protein composition distribution genetic improvement rice quality
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Electric Vehicle Charging Capacity of Distribution Network Considering Conventional Load Composition 被引量:1
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作者 Pengwei Yang Yuqi Cao +4 位作者 Jie Tan Junfa Chen Chao Zhang Yan Wang Haifeng Liang 《Energy Engineering》 EI 2023年第3期743-762,共20页
At present,the large-scale access to electric vehicles(EVs)is exerting considerable pressure on the distribution network.Hence,it is particularly important to analyze the capacity of the distribution network to accomm... At present,the large-scale access to electric vehicles(EVs)is exerting considerable pressure on the distribution network.Hence,it is particularly important to analyze the capacity of the distribution network to accommodate EVs.To this end,we propose a method for analyzing the EV capacity of the distribution network by considering the composition of the conventional load.First,the analysis and pretreatment methods for the distribution network architecture and conventional load are proposed.Second,the charging behavior of an EVis simulated by combining the Monte Carlo method and the trip chain theory.After obtaining the temporal and spatial distribution of the EV charging load,themethod of distribution according to the proportion of the same type of conventional load among the nodes is adopted to integrate the EV charging load with the conventional load of the distribution network.By adjusting the EV ownership,the EV capacity in the distribution network is analyzed and solved on the basis of the following indices:node voltage,branch current,and transformer capacity.Finally,by considering the 10-kV distribution network in some areas of an actual city as an example,we show that the proposed analysis method can obtain a more reasonable number of EVs to be accommodated in the distribution network. 展开更多
关键词 Capacity charging load distribution charging load forecasting conventional load composition electric vehicle trip behavior
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Distribution and composition of tintinnids ciliates in the northern South China Sea during summer 被引量:1
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作者 刘华雪 黄良民 +3 位作者 谭烨辉 宋星宇 黄建荣 李涛 《Marine Science Bulletin》 CAS 2010年第2期38-46,共9页
Tintinnids were enumerated and identified in samples collected from 36 stations between 18°-22°N, 107°-122 °E in the northern South China Sea (NSCS). 44 species belonging to 24 genera of tintinni... Tintinnids were enumerated and identified in samples collected from 36 stations between 18°-22°N, 107°-122 °E in the northern South China Sea (NSCS). 44 species belonging to 24 genera of tintinnids were recorded. The dominant species were He/icostome/la /onga and Tintinnopsis radix. Tintinnids abundance ranged from 0 to 2 200 cell/L, and mean abundance was 221cell/L in the surface water. Tintinnids abundance and species numbers decreased from coast to offshore. Upwelling and Pearl River discharge influenced the distribution of tintinnids by regulating nutrients supply. Maximum abundance (2 200 cell/L) was found in the surface water of A1. Tintinnids abundance showed positive relationship with chlorophyll a (Chl a) concentration, and no significant relationship was found between tintinnids abundance and temperature. 展开更多
关键词 TINTINNIDS composition distribution northern South China Sea
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Distribution and Formation Causes of PM_(2.5) and O_(3) Double High Pollution Events in China during 2013–20
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作者 Zhixuan TONG Yingying YAN +6 位作者 Shaofei KONG Jintai LIN Nan CHEN Bo ZHU Jing MA Tianliang ZHAO Shihua QI 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2024年第6期1235-1250,I0004-I0021,共34页
Fine particulate matter(PM_(2.5))and ozone(O_(3))double high pollution(DHP)events have occurred frequently over China in recent years,but their causes are not completely clear.In this study,the spatiotemporal distribu... Fine particulate matter(PM_(2.5))and ozone(O_(3))double high pollution(DHP)events have occurred frequently over China in recent years,but their causes are not completely clear.In this study,the spatiotemporal distribution of DHP events in China during 2013–20 is analyzed.The synoptic types affecting DHP events are identified with the Lamb–Jenkinson circulation classification method.The meteorological and chemical causes of DHP events controlled by the main synoptic types are further investigated.Results show that DHP events(1655 in total for China during 2013–20)mainly occur over the North China Plain,Yangtze River Delta,Pearl River Delta,Sichuan Basin,and Central China.The occurrence frequency increases by 5.1%during 2013–15,and then decreases by 56.1%during 2015–20.The main circulation types of DHP events are“cyclone”and“anticyclone”,accounting for over 40%of all DHP events over five main polluted regions in China,followed by southerly or easterly flat airflow types,like“southeast”,“southwest”,and“east”.Compared with non-DHP events,DHP events are characterized by static or weak wind,high temperature(20.9℃ versus 23.1℃)and low humidity(70.0%versus 64.9%).The diurnal cycles of meteorological conditions cause PM_(2.5)(0300–1200 LST,Local Standard Time=UTC+8 hours)and O_(3)(1500–2100 LST)to exceed the national standards at different periods of the DHP day.Three pollutant conversion indices further indicate the rapid secondary conversions during DHP events,and thus the concentrations of NO_(2),SO_(2) and volatile organic compounds decrease by 13.1%,4.7%and 4.4%,respectively.The results of this study can be informative for future decisions on the management of DHP events. 展开更多
关键词 double high pollution events PM_(2.5) OZONE spatiotemporal distribution meteorological causes chemical composition characteristics
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Fish Assemblage and Abundance Distribution in Nanji Islands Marine Nature Reserve in Relation to Season Change
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作者 Cheikh Sarr Cungen Yu +2 位作者 Ousmane Ndiaye Hamet Diadhiou Ngor Ndour 《Journal of Agricultural Chemistry and Environment》 2024年第1期13-32,共20页
The fishing survey station located in the warm waters of the East China Sea is one of the abundant fishery resources of waters;with a large number of economic fish breeding grounds and economic juvenile feeding ground... The fishing survey station located in the warm waters of the East China Sea is one of the abundant fishery resources of waters;with a large number of economic fish breeding grounds and economic juvenile feeding grounds. Several fish species according to this bottom trawl survey results which appear in the annual survey from winter to autumn give us a total of 58 species, which have appeared throughout the year. But the vast majority of species appears only in certain seasons, according to the sea fish survey and based on seasonal migratory species or species mainly small endemic species. The survey of fish is tropical and subtropical warm water species and warm temperate species, and the history of the area has several types of 397 different species. There are many reasons, in addition to recent years, human disturbance and adverse consequences of environmental changes brought about, but also with the relevant sampling methods and sampler time, the survey sampled only trawl based, from Ping yang Ocean and Fisheries Bureau, the waters are still other jobs method net, gill nets, fishing industry, etc. Survey results show that the type of fish in the summer (58 species) > spring (55 species) > winter (51 species) > autumn (42 species). The type of season was among spring to summer rose, summer to autumn decline. The survey found that in the reef area of the Nanji Islands, no one species of fish is the dominant species throughout the year (according to the dominant species, each species is dominant only in one season). From the dominant species turnover accounting for the four seasons, in winter it has 53.72% of the total biomass or annual biomass, spring it has 41.53% of the overall biomass, summer it has 31.85% and autumn it has 38.56% of total biomass. Visible, seasonal succession of dominant species of fish phenomenon is very obvious, especially in the spring and winter, summer transfers dominate species at this stage show the greatest change, but winter, the transfer of this dominant species changes in minimal. Seasonal changes from biomass and the average annual marine fish survey biomass were 4832.25 g/h. From different seasons, the average biomass in winter (10779.88 g/h) > of the average biomass in spring (3624.1 g/hour) > of the mean biomass in autumn (3158 g/h) > the average Biomass in summer (1767 g/h). All of them show significant seasonal variation of the biomass, in winter and spring, the biomass is generally not high, but significantly higher than in the summer and autumn seasons. Each season, around the coast of southern Zhejiang, is less than the biomass and other catches off, which involves investigating sea location, size range, and the survey ship different network related tools. Another change from the area of biomass, some studies found that the survey of four-season fish of waters above the biological capacity of several kilograms only in some stations, namely stations and the highest biomass in summer appeared in stations 3, 7 and 11. In autumn the highest biomass appeared in stations 3, 6, 20 and 23. 展开更多
关键词 Nanji Islands Species composition Abundance distribution SEASONS
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Zooplankton composition and distribution in the Lembeh Strait of North Sulawesi, Indonesia 被引量:5
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作者 WANG Yanguo CHEN Xiaoyin +5 位作者 XING Bingpeng SUN Rouxin FITRIA Nurul XIANG Peng WANG Chunguang LIN Mao 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2018年第12期35-44,共10页
Based on oceanographic survey data in June 2012 in the Lembeh Strait, the zooplankton ecological characteristics such as species composition, individual abundance, dominant species and distribution were analyzed. The ... Based on oceanographic survey data in June 2012 in the Lembeh Strait, the zooplankton ecological characteristics such as species composition, individual abundance, dominant species and distribution were analyzed. The results showed that 183 species(including 4 sp.) had been recognized, most of them belonged to copepoda.Cnidaria followed with 43 species(including 1 sp.) were identified. The average abundance of zooplankton was(150.47±58.91) ind./m3. As to the horizontal distribution, the abundance of the zooplankton was higher in the southern waters than in the northern waters. The dominant species in the study area were Lensia subtiloides,Sagitta enflata, Lucifer intermedius, Oikopleura rufescens, Diphyes chamissoni, Creseis acicula, Subeucalanus subcrassus, Temora discaudata, Aglaura hemistoma, Doliolum denticulatum, Canthocalanus pauper, Oikopleura longicauda and Nanomia bijuga. Zooplankton biodiversity indexes were higher in study area than previous study in the other regions. The findings from this study provide important baseline information for future research and monitoring programs. 展开更多
关键词 ZOOPLANKTON species composition dominant species distribution Lembeh Strait
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Vegetation composition and distribution on the northern slope of Karlik Mountain to Naomaohu basin,East Tianshan Mountains 被引量:3
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作者 YiBing QIAN HaiYan ZHANG +1 位作者 ZhaoNing WU ZhongChen WANG 《Journal of Arid Land》 SCIE 2011年第1期15-24,共10页
This paper reports the characteristics of plant flora in the region of the northern slope of Karlik Mountain to Naomaohu basin, based on field investigation of the vegetation and referring to relevant literature. The ... This paper reports the characteristics of plant flora in the region of the northern slope of Karlik Mountain to Naomaohu basin, based on field investigation of the vegetation and referring to relevant literature. The results show that the flora of the study area mainly consists of communities of single species or a limited number of species, genera and families. The flora composition is marked by the phenomenon of dominant families and genera; the temperate element occupies a dominant position, while in terms of the genera the Tethys element is an important component. Areal-types of the species are dominated by the floral element of Asian Central-part with xerophytic characteristic, and the life-forms of plants are mainly perennial and herbaceous. These characteristics reflect that the compositions of the species in this region possess both ancient and young elements. Analysis of the relationship between the species composition, plant community diversity and altitude gradient, we found that the structure of the vegetation has an obvi- ous vertical distribution. The lower and higher altitude areas, where the climate conditions are relative in- clement, are mainly occupied by the plant communities with simple structure and single dominant popula- tion, while the species richness in the mid-altitude area increases with favorable temperature and precipi- tation. Consequently, the species diversity and evenness indices show single-peak distribution with increasing elevation (about 〈 2500 m), while the dominance indices decrease in elevation from 500 m to 2500 m and increase in elevation of 〉 2500 m. 展开更多
关键词 Karlik Mountain to Naomaohu basin VEGETATION composition distribution
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Effect of chemical composition on the element distribution,phase composition and calcification roasting process of vanadium slag 被引量:4
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作者 Tangxia Yu Tao Jiang +3 位作者 Jing Wen Hongyan Sun Ming Li Yi Peng 《International Journal of Minerals,Metallurgy and Materials》 SCIE EI CAS CSCD 2022年第12期2144-2151,共8页
The chemical composition of vanadium slag significantly affects its element distribution and phase composition,which affect the subsequent calcification roasting process and vanadium recovery.In this work,seven kinds ... The chemical composition of vanadium slag significantly affects its element distribution and phase composition,which affect the subsequent calcification roasting process and vanadium recovery.In this work,seven kinds of vanadium slags derived from different regions in China were used as the raw materials to study the effects of different components on the vanadium slag’s elements distribution,phase composition,calcification roasting,and leaching rate of major elements using scanning electron microscope,X-ray diffraction analysis,and inductively coupled plasma-optical emission spectroscopy.The results show that the spinel phase is wrapped with silicate phase in all vanadium slag samples.The main elements in the spinel phase are Cr,V,and Ti from the interior to the exterior.The size of spinel phase in low chromium vanadium slag is larger than the other vanadium slags with higher chromium contents.The spinel phase of high-calcium and high-phosphorus vanadium slag is more dispersed.The strongest diffraction peak of vanadium spinel phase in the vanadium slag migrates to a higher diffraction angle,and(Fe_(0.6)Cr_(0.4))_(2)O_(3)is formed after calcification roasting as the chromium content increased.A large amount of Ca_(2)SiO_(4)is produced because excess Ca reacts with Si in high-calcium and high-phosphorus vanadium slag.The vanadium leaching rate reaches 88%in some vanadium slags.The chromium leaching rate is less than 5%in all vanadium slags.The silicon leaching rate of high-calcium and high-phosphorus vanadium slag is much higher than that of the other slags.The leaching rate of manganese is higher than 10%,and the leaching rates of iron and titanium are negligible. 展开更多
关键词 vanadium slag calcification roasting element distribution phase composition leaching rate
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SPECIES COMPOSITION, HORIZONTAL DISTRIBUTION AND SEASONAL SUCCESSION OF PHYTOPLANKTON IN THE CHANNEL FROM DONGTING LAKE TO THE CHANGJIANG RIVER, CHINA 被引量:2
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作者 魏印心 《Chinese Journal of Oceanology and Limnology》 SCIE CAS CSCD 2002年第2期142-148,共7页
The species composition, horizontal distribution and seasonal succession of the phytoplankton at five sampling stations in the channel between Dongting Lake and the Changjiang River, China were studied from May 1995 t... The species composition, horizontal distribution and seasonal succession of the phytoplankton at five sampling stations in the channel between Dongting Lake and the Changjiang River, China were studied from May 1995 to December 1997. A total of 416 taxa were observed; diatoms comprised the most diverse taxonomic group representing 58.2 % of the total species. The β-mesotrophic indicators were 92 taxa or 22 % of the total, the α-mesotrophic or α,β-eutrophic indicators decreased distinctly to 20 taxa or 4.8 % of the total. The species number and composition of various phyla were approximately similar at Stations 1, 2, 3 and 4, but at Station 5 the number of species was the minimum and the ratio of diatoms to total phytoplankton in the number of species was the highest. In seasonal succession of the phytoplankton species, the number was the highest in May and June, lower in December, January, March and July in the channel. The dominant species were different in different months. The ratio of diatoms species number to blue green algae and green algae species number diminished gradually from winter to summer and autumn, and then increased gradually from autumn to winter and early spring in the annual cycle. Margalef, Simpson and Shannon-Weaver diversity indices changed in different months, their values were higher in winter, lower in summer. Nygaard’s diatoms quotients were lower in winter, then in spring and autumn, higher in summer. These results indicated that the water quality was the best in winter, better in spring and autumn than in summer. The relationship between the structure of the phytoplankton community and the water environmental quality was discussed. 展开更多
关键词 PHYTOPLANKTON species composition horizontal distribution seasonal succession Dongting Lake
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The distribution and variation in the gas composition of macro-seeps on the near-shore Lingtou Promontory in the South China Sea 被引量:1
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作者 DI Pengfei FENG Dong CHEN Duofu 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2016年第11期120-125,共6页
Natural hydrocarbon seeps in a marine environment are one of the important contributors to greenhouse gases in the atmosphere,including methane,which is significant to the global carbon cycling and climate change.Four... Natural hydrocarbon seeps in a marine environment are one of the important contributors to greenhouse gases in the atmosphere,including methane,which is significant to the global carbon cycling and climate change.Four hydrocarbon seep areas,the Lingtou Promontory,the Yinggehai Rivulet mouth,the Yazhou Bay and the Nanshan Promontory,occurring in the Yinggehai Basin delineate a near-shore gas bubble zone.The gas composition and geochemistry of venting bubbles and the spatial distribution of hydrocarbon seeps are surveyed on the near-shore Lingtou Promontory.The gas composition of the venting bubbles is mainly composed of CO_2,CH_4,N_2 and O_2,with minor amounts of non-methane hydrocarbons.The difference in the bubbles' composition is a possible consequence of gas exchange during bubble ascent.The seepage gases from the seafloor are characterized by a high CO_2 content(67.35%) and relatively positive δ^(13)C_(V_PDB) values(-0.49×10^(-3)-0.86×10^(-3)),indicating that the CO_2 is of inorganic origin.The relatively low CH_4 content(23%) and their negative δ^(13)C_(V-PDB) values(-34.43×10^(-3)--37.53×10^(-3)) and high ratios of C_1 content to C_(1-5) one(0.98-0.99)as well point to thermogenic gases.The hydrocarbon seeps on the 3.5 Hz sub-bottom profile display a linear arrangement and are sub-parallel to the No.1 fault,suggesting that the hydrocarbon seeps may be associated with fracture activity or weak zones and that the seepage gases migrate laterally from the central depression of the Yinggehai Basin. 展开更多
关键词 hydrocarbon seeps gas composition distribution nearshore Yinggehai northern South China Sea
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Determination of element composition of three lichens and their distribution in King George Island, Antarctica 被引量:1
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作者 李永良 周云龙 张正旺 《Chinese Journal of Polar Science》 2000年第2期141-146,共6页
Cross-section slices of Usnea antarctica Du Rietz, Usnea aurantiaco-atra (Jacq.) Bory. and Cladonia sp. at upper, middle and basal positions were prepared, respectively. The element composition and relative... Cross-section slices of Usnea antarctica Du Rietz, Usnea aurantiaco-atra (Jacq.) Bory. and Cladonia sp. at upper, middle and basal positions were prepared, respectively. The element composition and relative content were determined by SEM and EDS at the surface, intermediate and inner layers in each slice, respectively. The result indicated that the composition of element is mostly same in these lichens. The relative content of Al, Si, K and Ca elements is high,and P is close at each position. The result is of benefit to study the structure and physiological characteristics of lichens, and to analyze geological environment in Antarctica. 展开更多
关键词 ANTARCTICA LICHEN element composition distribution.
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Seasonal size composition and abundance distribution of Euphausia pacifica in relation to environmental factors in the southern Yellow Sea
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作者 Tao Zuo Hui Liu 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2019年第2期70-77,共8页
The seasonal size structure and spatial abundance distributions of Euphausia pacifica populations were investigated in the central part of southern Yellow Sea from August 2009 to May 2010.The abundance and biomass of ... The seasonal size structure and spatial abundance distributions of Euphausia pacifica populations were investigated in the central part of southern Yellow Sea from August 2009 to May 2010.The abundance and biomass of E.pacifica were higher in spring and summer,and lower in autumn and winter.The mean abundance and biomass(calculated by carbon)were 74.94 ind./m^3 and 8.23 mg/m^3,respectively.Females with total length(TL)ranging between 10 and 19 mm in summer had a substantial contribution to the population biomass,whereas larvae of TL of 3–7 mm in spring were the main contributor to the population abundance.The sex ratio(female:male)showed a female bias in four seasons.Its value peaked in summer,and then decreased in autumn,spring,and winter successively.Cohort analysis revealed that the length-frequency distribution of E.pacifica could be characterized as one group with large animals(mean TL>12 mm)accompanied by one or two subgroups of small individuals(mean TL<7 mm).Regarding the spatial distribution,juveniles and adults of E.pacifica tend to concentrate in relatively deep water with low temperature(~11℃)and high salinity(>32),whereas its larvae showed more abundance in inshore water with rich chlorophyll a,low salinity(<32),and warm temperature(>11℃),especially in summer and autumn.Associations changed seasonally between stage-specific abundance and environmental factors. 展开更多
关键词 spatial distribution size composition BIOMASS Euphausia pacifica YELLOW Sea
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COMPOSITION AND DISTRIBUTION OF VEGETATION IN COLD TEMPERATE REGION OF NORTHEASTERN PART OF CHINA
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作者 叶万辉 孙国华 《Journal of Northeast Forestry University》 SCIE CAS CSCD 1996年第1期17-20,共4页
Cold-temperate region of China is an independent and the most northern one of the 8 vegetaion regions of China. The specitic composition of the vegetation in this region, besides the polytopic species, East-Siberia fl... Cold-temperate region of China is an independent and the most northern one of the 8 vegetaion regions of China. The specitic composition of the vegetation in this region, besides the polytopic species, East-Siberia floral element is dominant (51.5%), but mixed with Mandshurica (38.7%) and Mongolia (2.3%) in horizntal vegetation zone. The floral elements vary greatly with altitude, in higher and the highest Parts, they are mixed with Kantcaja-Erhock and Arctic alpine floral eleinents. The vertical distribution include 3 zones: subalpine dwarf forest zone, mountainous coniferous wood land zone and mountainous coniferous forest zone, and the last one include 3 subzones. 展开更多
关键词 composition distribution VEGETATION Cold-temperate
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Composition Distribution in the MnxCd(1-x)In2Te4 Ingot Grown by ACRT-B Method
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作者 Yongqin CHANG, Wanqi JIE, Xiping GUO, Fuyi CHEN and Weijun ANState Key Laboratory of Solidification Processing, Northwestern Polytechnical University, Xi’an 710072, China 《Journal of Materials Science & Technology》 SCIE EI CAS CSCD 2003年第6期610-612,共3页
MnxCd1-xln2Te4 (x=0.1) ingot was successfully grown by the modified Bridgman technique, which applied the accelerated crucible rotation technique (ACRT) in Bridgman process, or briefly ACRT-B. The growth interface pro... MnxCd1-xln2Te4 (x=0.1) ingot was successfully grown by the modified Bridgman technique, which applied the accelerated crucible rotation technique (ACRT) in Bridgman process, or briefly ACRT-B. The growth interface profile shape and the composition distribution in the MnxCd1-xln2Te4 (x=0.1) ingot were analyzed. Even though the stoichiometric composition was synthesized in the original ingot, the composition has been redistributed during the ACRT-B growth process. Mn and Cd contents decrease while In increases along the longitudinal axis. The partition ratios of solutes Mn, Cd and In at the growth interface are evaluated by a mathematical method based on the experimental data, which are found to be 1.286, 1.926 and 0.729 in α phase growth process, and 1.120, 1.055 and 0.985 in β phase growth process, respectively. In the radial direction, Mn and Cd contents increase while In decreases with the distance from the centerline of the ingot. 展开更多
关键词 MnxCd1-xIn2Te4 ACRT-B composition distribution Partition ratio
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Composition and ecological distribution of forest soil animalin Confucian graveyard of Qufu
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作者 刘红 《Journal of Forestry Research》 SCIE CAS CSCD 1999年第3期178-180,共3页
Soil animal communities of Secondary forest,Platycladus forest andQuercus acutissima forest in Confucian graveyard of Qufu were investigated. 3583 specimens were collected, belonging separately to 5 Phylums, 11 Classe... Soil animal communities of Secondary forest,Platycladus forest andQuercus acutissima forest in Confucian graveyard of Qufu were investigated. 3583 specimens were collected, belonging separately to 5 Phylums, 11 Classes and 23 Orders. Two dominant groups and 9 common groups account for 94.45% of the total numbers. The soil animals in these three forest habitats differ in composition, ecological distribution and important indices. The dominant groups of soil animals in the three forests were the same, but other groups differ more greatly. Diversity index (H′) and evenness index (E) of soil animal in Secondary forest are the highest, and yet dominance index (C) inQuercus acutissima forest is the highest. Most soil animals in each forest habitats congregate to the surface soil layer. Their sorts and individual numbers are all layer I>II>III. It is very similar for composition of soil animals in the three forests. 展开更多
关键词 Forest soil animal Species composition and distribution Confucian graveyard of Qufu
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Composition and distribution of diatom assemblages in the surface sediments of the Bering Sea
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作者 SHAO Lixia LIN Rongcheng +1 位作者 GAO Yahui HUANG Dingyong 《Advances in Polar Science》 2013年第3期167-174,共8页
Diatoms collected from the top 1 cm of the surface sediment layer at seven Bering Sea stations during the Fourth Chi- nese National Arctic Research Expedition (4th CH1NARE-Arctic) in 2010 were studied. In total, 101... Diatoms collected from the top 1 cm of the surface sediment layer at seven Bering Sea stations during the Fourth Chi- nese National Arctic Research Expedition (4th CH1NARE-Arctic) in 2010 were studied. In total, 101 taxa belonging to 38 genera were found. The species were divided into four groups: eurythermal species, boreal-temperate species, polar species, and sea-ice species. The diatom assemblages at the stations in the southwestern basin area were primarily composed of boreal-temperate species, such as Neodenticula seminae, Thalassiosira trifulta, Rhizosolenia hebetata f. hiemalis, and Actinocyclus curvatulus. The northeastern shelf stations were dominated by polar species, including Fragilariopsis oceanica, Thalassiosira antarctica spora, Thalassiosira nordensldoeldii, and Thalassiosira hyalina. The overall abundance was highest at the basin stations with 3.7 ×10^6 cells·g^-1 of wet sediment, whereas the eastern shelf stations had the lowest abundance of 0.7×10^6 cells·g^-1 of wet sediment (excluding the resting spores of Chaetoceros spp.). The relationship between the distribution of the surface sediment diatom assemblages and the environment is discussed. 展开更多
关键词 Bering Sea surface sediment DIATOM species composition distribution
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Preparation and Composition Distribution in Hollow Tubular TiB-Ti Composites during Centrifugal Spraying Process
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作者 ZHANG Zhongren DU Runkun +3 位作者 ZHANG Fan ZHANG Jinyong LEI Liwen WANG Wei 《Journal of Wuhan University of Technology(Materials Science)》 SCIE EI CAS 2022年第3期518-524,共7页
The hollow cylinders of TiB-Ti composites with a gradient distribution of Ti phase were synthesized by the combination of traditional slurry spray with centrifugal forming process.The influences of the concentration o... The hollow cylinders of TiB-Ti composites with a gradient distribution of Ti phase were synthesized by the combination of traditional slurry spray with centrifugal forming process.The influences of the concentration of sodium hexametaphosphate(SHMP),the concentration of polyvinyl alcohol(PVA)and solid content(20 vol%-35 vol%)on the rheological properties of the TiB_(2)-Ti composite slurries were investigated.Slurries with low viscosity,weak thixotropy and shear-thinning behaviour were obtained for facilitating the slurry spraying process.The effects of different centrifugal conditions on the migration of components during the forming process were studied.The phase composition and the elements distribution of the prepared samples were characterized by the energy-dispersive X-ray spectrometer.The observations revealed that the samples fabricated at 1500 r/min for 3 min had a significant composition variation.For two-phase systems with small density differences and large particle size variation,centrifugal time was more important than centrifugal speed in forming a continuous gradient structure. 展开更多
关键词 hollow tubular TiB-Ti composites centrifugal spraying process rheological properties composition distribution
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Hydrocarbon Composition of Different VGO Feedstocks and Its Correlation with FCC Product Distribution
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作者 Song Haitao Jiao Guofeng +3 位作者 Zhu Xinyi Zhou Xiang Zhu Yuxia Da Zhijian 《China Petroleum Processing & Petrochemical Technology》 SCIE CAS 2013年第1期32-39,共8页
Three different types of VGO were selected and cut into various distillates by true boiling-point distillation (TBD), and the distillates were further separated into different components (saturates, aromatics and r... Three different types of VGO were selected and cut into various distillates by true boiling-point distillation (TBD), and the distillates were further separated into different components (saturates, aromatics and resins) via solid phase extrac- tion (SPE). The hydrocarbon components in saturates and aromatics were characterized on the quasi-molecular level by GC/ MS and CJC/TOF MS. Cracking reactions of VGO, their distillates, and hydrocarbon components (saturates and aromatics) were performed on an ACE (model AP) unit. Nine correlation parameters (mainly based on the previous assumption of basic structure Units, BSU) which could better reflect the structures and compositions of hydrocarbons were put forward based on the quasi-molecular level analysis data, and correlated with FCC product distribution by multi-regression method. A series of correlation formulas were obtained. The formulas were further verified by comparing experimental and calculated FCC yields emanated from two other VGO feedstocks. 展开更多
关键词 fluid catalytic cracking VGO product distribution hydrocarbon composition CORRELATION
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Size Distributions of Atmospheric Aerosol Compositions in Saitama, Japan
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作者 Ittipol Paw-Armart Kunio Yoshizumi 《Open Journal of Air Pollution》 2013年第1期1-6,共6页
A survey of atmospheric aerosols in a suburban area near Tokyo, Japanwas conducted using an Andersen sampler. Significant amounts of Na+and Cl- collected were considered to be derived from sea salt. The difference bet... A survey of atmospheric aerosols in a suburban area near Tokyo, Japanwas conducted using an Andersen sampler. Significant amounts of Na+and Cl- collected were considered to be derived from sea salt. The difference between the Na+/Cl-ratio in the area and that in sea salt indicated a considerable loss of Cl-. This is assumed to be caused by the formation of NaNO3, which is one of the main nitrate species present. Most of the sulfate in the sample was found to be (NH4)2SO4 in the form of fine particles, which is different from the sulfate derived from sea salt and soil. The size distributions of K and Mg are also discussed in relation to particular sources. 展开更多
关键词 Size distribution Chemical compositionS PARTICULATE MATTER SULFATE NITRATE Saitama JAPAN
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Improvement of the carrier distribution with GaN/InGa N/AlGaN/InGaN/GaN composition-graded barrier for InGaN-based blue light-emitting diode 被引量:1
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作者 Min Guo Zhi-You Guo +2 位作者 Jing Huang Yang Liu Shun-Yu Yao 《Chinese Physics B》 SCIE EI CAS CSCD 2017年第2期499-504,共6页
In Ga N light-emitting diodes(LEDs) with Ga N/In Ga N/Al Ga N/In Ga N/Ga N composition-graded barriers are proposed to replace the sixth and the middle five Ga N barriers under the condition of removing the electron... In Ga N light-emitting diodes(LEDs) with Ga N/In Ga N/Al Ga N/In Ga N/Ga N composition-graded barriers are proposed to replace the sixth and the middle five Ga N barriers under the condition of removing the electron blocking layer(EBL)and studied numerically in this paper. Simulation results show that the specially designed barrier in the sixth barrier is able to modulate the distributions of the holes and electrons in quantum well which is adjacent to the specially designed barrier. Concretely speaking, the new barrier could enhance both the electron and hole concentration remarkably in the previous well and reduce the hole concentration for the latter one to some extent along the growth direction. What is more,a phenomenon, i.e., a better carrier distribution in all the wells, just appears with the adoption of the new barriers in the middle five barriers, resulting in a much higher light output power and a lower efficiency droop than those in a conventional LED structure. 展开更多
关键词 composition-graded barriers light-emitting diodes carrier distribution
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