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Evaluation of sugar and organic acid composition and their levels in highbush blueberries from two regions of China 被引量:10
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作者 ZHANG Jia NIE Ji-yun +5 位作者 LI Jing ZHANG Hui LI Ye Saqib FAROOQ Syed Asim Shah BACHA WANG Jie 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2020年第9期2352-2361,共10页
Sweet and sour are the most important taste of blueberries,and they are produced by sugar and acid,respectively.Their contributions to the taste depend not only on the levels of sugar and acid,but also on the types an... Sweet and sour are the most important taste of blueberries,and they are produced by sugar and acid,respectively.Their contributions to the taste depend not only on the levels of sugar and acid,but also on the types and relative proportions of sugar and acid.Therefore,it is very important to evaluate the composition and levels of sugar and acid in blueberries.Regional differences and variety diversity also affect the sugar and acid characteristics of fruits.Therefore,this study selected two main producing regions in northern China(Weihai and Yingkou)to examine the sugar and acid characteristics of 11 common blueberry cultivars.The indexes measured included soluble sugars,organic acids,soluble solid content and titratable acidity.The results showed that glucose and fructose were the major sugars,and citric acid and quinic acid were the major organic acids.Correlation analysis showed that glucose,fructose,and sucrose were positively correlated with total sugar content;the citric acid content was positively correlated with the titratable acidity and total organic acids.Titratable acidity,glucose,fructose,sucrose,total sugar content,citric acid,shikimic acid and total acid content of the blueberries varied significantly between regions(P<0.05).In general,compared with Weihai blueberries,Yingkou blueberries had higher sugar content and lower acid content.The results of this study may provide useful references for the evaluation of sweet and sour flavors and cultivar selection of blueberries. 展开更多
关键词 BLUEBERRY SUGAR organic acid level EVALUATION
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Attitudes,awareness,and knowledge levels of the Turkish adult population toward organ donation:Study of a nationwide survey 被引量:2
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作者 Sami Akbulut Ali Ozer +3 位作者 Ayse Gokce Khaled Demyati Hasan Saritas Sezai Yilmaz 《World Journal of Clinical Cases》 SCIE 2020年第11期2235-2245,共11页
BACKGROUND The most important factors affecting attitudes on organ donation are socioeconomic, educational, cultural, and religious factors in many countries.AIM To evaluate the attitudes, awareness, and knowledge lev... BACKGROUND The most important factors affecting attitudes on organ donation are socioeconomic, educational, cultural, and religious factors in many countries.AIM To evaluate the attitudes, awareness, and knowledge levels of the Turkish adult population toward organ donation.METHODS This nationwide study surveyed 3000 adults(≥ 18 years) in Turkey. To ensure a representative sample, the Nomenclature of Territorial Units for Statistics-Ⅱ(modified for Turkey) was used. Turkey was divided into 26 regions based on social, economic, and geographic criteria as identified by the Turkish Statistical Institute. A stratified sampling method was used with an even distribution of adults across cities and towns based on population data. Data were collected by the PRP Research and Consultancy Company using computer-assisted personal interviews.RESULTS Out of 3000 individuals represented in the study population, 1465(48.8%) were male and 1535(51.2%) female. The results showed that most participants were under 45 years(59.0%) and married(72.1%), some had a bachelor’s degree or higher(21.9%), and very few(1.5%) had any direct experience with organ transplantation-whether in the family, or a family member on a transplantation waiting list. Most of the study population(88.3%) had not considered donating an organ, however, most(87.9%) said that they would accept an organ from a donor if they needed one. Among the individuals surveyed, 67% were willing to donate an organ to a close relative, while 26.8% would donate an organ to an unrelated person. Only 47.2% said they had adequate information about brain death, and 85.2% refused to consent to donating organs of family members declared brain dead. Only 33.9% thought they had adequate information about organ donation. The main source of information was the television. The two main reasons for refusing organ donation were that it was too soon to think about organ donation and the importance of retaining the integrity of the dead person’s body.CONCLUSION This study showed that Turkey’s adult population has inadequate knowledge about organ donation. The study advocates for public education programs to increase awareness among the general population about legislation related to organ donation. 展开更多
关键词 organ donation Adult population ATTITUDES Knowledge levels AWARENESS Barriers to the organ donation
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Biomass accumulation and organic carbon stocks of Kandelia obovata mangrove vegetation under different simulated sea levels 被引量:1
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作者 Jiahui Chen Min Gao +2 位作者 Guangcheng Chen Heng Zhu Yong Ye 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2022年第8期78-86,共9页
Mangrove forests are vulnerably threatened by sea level rise(SLR).Vegetation organic carbon(OC)stocks are important for mangrove ecosystem carbon cycle.It is critical to understand how SLR affects vegetation OC stocks... Mangrove forests are vulnerably threatened by sea level rise(SLR).Vegetation organic carbon(OC)stocks are important for mangrove ecosystem carbon cycle.It is critical to understand how SLR affects vegetation OC stocks for evaluating mangrove blue carbon budget and global climate change.In this study,biomass accumulation and OC stocks of mangrove vegetation were compared among three 10 year-old Kandelia obovata(a common species in China)mangrove forests under three intertidal elevations through species-specific allometric equations.This study simulated mangrove forests with SLR values of 0 cm,40 cm and 80 cm,respectively,representing for the current,future~100 a and future~200 a SLR of mangrove forests along the Jiulong River Estuary,China.SLR directly decreased mangrove individual density and inhibited the growth of mangrove vegetation.The total vegetation biomasses were(12.86±0.95)kg/m^2,(7.97±0.90)kg/m^2 and(3.89±0.63)kg/m^2 at Sites SLR 0 cm,SLR40 cm and SLR 80 cm,respectively.The total vegetation OC stock decreased by approximately 3.85 kg/m^2(in terms of C)from Site SLR 0 cm to Site SLR 80 cm.Significantly lower vegetation biomass and OC stock of various components(stem,branch,leaf and root)were found at Site SLR 80 cm.Annual increments of vegetation biomass and OC stock also decreased with SLR increase.Moreover,significant lower sedimentation rate was found at Site SLR 80 cm.These indicated that SLR will decrease mangrove vegetation biomass and OC stock,which may reduce global blue carbon sink by mangroves,exacerbate global warming and give positive feedback to SLR. 展开更多
关键词 sea level rise vegetation biomass organic carbon stock COMPONENT mangrove forest Kandelia obovata
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Influence of Energy Level Matching on Device Performances of Organic Light-emitting Diodes 被引量:1
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作者 LIUChen ZOUXue-cheng YINSheng 《Semiconductor Photonics and Technology》 CAS 2004年第3期174-178,共5页
Through experiments and computer simulation,the influence of the energy levels of organic materials and electrode materials in the organic light-emitting diodes (OLEDs) on the device performances is discussed.Results ... Through experiments and computer simulation,the influence of the energy levels of organic materials and electrode materials in the organic light-emitting diodes (OLEDs) on the device performances is discussed.Results show that the device performances are influenced by not only the carrier injection barriers at the electrode interface but also the barriers at the organic heterojunction interface.This result is helpful to the selection of the organic materials and their arrangement in the optimal design of OLEDs. 展开更多
关键词 organic light-emitting diode Energy level matching Luminous efficiency SIMULATION
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Red Organic Light-Emitting Diodes Based on Energy Levels Matching of Dopant with the Host Materials
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作者 朱文清 蒋雪茵 +1 位作者 张志林 许少鸿 《Journal of Shanghai University(English Edition)》 CAS 2003年第2期191-195,共5页
By doping red dye 4 dicyanomethylene 2 ( tert butyl) 6 methyl 4H pyran(DCJTB) in the tris (8 hydroxyquinolinato) metal Mq 3(where M = Al, Ga, In) chelate complexes, a series of red dopant organic light ... By doping red dye 4 dicyanomethylene 2 ( tert butyl) 6 methyl 4H pyran(DCJTB) in the tris (8 hydroxyquinolinato) metal Mq 3(where M = Al, Ga, In) chelate complexes, a series of red dopant organic light emitting diodes with different doping concentrations have been fabricated. The electroluminescence efficiency of these red diodes with a DCJTB doped Mq 3 emitting layer is found to be decreased markedly with the increasing of doping concentration. Electroluminescence characteristics of these devices are studied in terms of energy levels matching of red dopant with the host materials and carrier transporting layers. 展开更多
关键词 organic electroluminescence red dopant energy transfer energy levels matching
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Organic Carbon Deposition on the Inner Shelf of the East China Sea Constrained by Sea Level and Climatic Changes Since the Last Deglaciation
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作者 ZHANG Mingyu LIU Xiting +7 位作者 XU Fangjian LI Anchun GU Yu CHANG Xin ZHUANG Guangchao ZHANG Kaidi BI Naishuang WANG Houjie 《Journal of Ocean University of China》 SCIE CAS CSCD 2023年第5期1300-1312,共13页
The East China Sea(ECS),which is located in the transitional zone between land and ocean,is the main site for the burial of sedimentary organic carbon.Despite good constraints of the modern source to the sinking proce... The East China Sea(ECS),which is located in the transitional zone between land and ocean,is the main site for the burial of sedimentary organic carbon.Despite good constraints of the modern source to the sinking process of organic carbon,its fate in response to changes in climate and sea level since the last deglaciation remains poorly understood.We aim to fill this gap by presenting a high-resolution sedimentary record of core EC2005 to derive a better understanding of the evolution of the depositional environment and its control on the organic deposition since 17.3 kyr.Our results suggest that sedimentary organic carbon was deposited in a terrestrial environment before the seawater reached the study area around 13.1 kyr.This significant transition from a terrestrial environment to a marine environment is reflected by the decrease in TOC/TN and TOC/TS ratios,which is attributed to deglacial sea level rise.The sea level continued to rise until it reached its highstand at approximately 7.3 kyr when the mud depocenter was developed.Our results further indicate that the deposition of the sedimentary organic carbon could respond quickly to abrupt cold events,including the Heinrich stadial 1 and the Younger Dryas during the last deglaciation,as well as‘Bond events'during the Holocene.We propose that the rapid response of the organic deposition to those cold events in the northern hemisphere is linked to the East Asian winter monsoon.These new findings demonstrate that organic carbon deposition and burial on the inner shelf could effectively document sea level and climatic changes. 展开更多
关键词 organic carbon East China Sea mud sediments sea level changes environmental evolution
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The Effect of Energy Levels of the Electron Acceptor Materials on Organic Photovoltaic Cells
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作者 Hassen Derouiche Sami Saidi Abdelatif Belhadj Mohamed 《Smart Grid and Renewable Energy》 2011年第3期278-281,共4页
Organic photovoltaic cells have been fabricated using copper phthalocyanine CuPc as electron donor and C60 or PCBM as electron acceptor. We have investigated the I-V measurements of two different structures: ITO/PEDOT... Organic photovoltaic cells have been fabricated using copper phthalocyanine CuPc as electron donor and C60 or PCBM as electron acceptor. We have investigated the I-V measurements of two different structures: ITO/PEDOT: PSS/(CuPc:C60 or CuPc:PCBM)/BCP/Al. We have observed that the substitution of PCBM by C60 scales up the photocurrent and the efficiency of the devices. As for the open-circuit voltage and the fill factor, we have seen that Voc and FF depend on the energy difference between the highest occupied molecular orbital (HOMO) of CuPc and the lowest unoccupied molecular orbital (LUMO)of C60 or PCBM. 展开更多
关键词 CUPC C60 PCBM Energy levels organic Photovoltaic Cells
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Substitution of chemical fertilizer by Chinese milk vetch improves the sustainability of yield and accumulation of soil organic carbon in a double-rice cropping system 被引量:16
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作者 ZHOU Xing LU Yan-hong +5 位作者 LIAO Yu-lin ZHU Qi-dong CHENG Hui-dan NIE Xin CAO Wei-dong NIE Jun 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2019年第10期2381-2392,共12页
The double-rice cropping system is a very important intensive cropping system for food security in China. There have been few studies of the sustainability of yield and accumulation of soil organic carbon (SOC) in the... The double-rice cropping system is a very important intensive cropping system for food security in China. There have been few studies of the sustainability of yield and accumulation of soil organic carbon (SOC) in the double-rice cropping system following a partial substitution of chemical fertilizer by Chinese milk vetch (Mv). We conducted a 10-year (2008–2017) field experiment in Nan County, South-Central China, to examine the double-rice productivity and SOC accumulation in a paddy soil in response to different fertilization levels and Mv application (22.5 Mg ha^–1). Fertilizer and Mv were applied both individually and in combination (sole chemical fertilizers, Mv plus 100, 80, 60, 40, and 0% of the recommended dose of chemical fertilizers, labeled as F100, MF100, MF80, MF60, MF40, and MF0, respectively). It was found that the grain yields of double-rice crop in treatments receiving Mv were reduced when the dose of chemical fertilizer was reduced, while the change in SOC stock displayed a double peak curve. The MF100 produced the highest double-rice yield and SOC stock, with the value higher by 13.5 and 26.8% than that in the F100. However, the grain yields increased in the MF80 (by 8.4% compared to the F100), while the SOC stock only increased by 8.4%. Analogous to the change of grain yield, the sustainable yield index (SYI) of double rice were improved significantly in the MF100 and MF80 compared to the F100, while there was a slight increase in the MF60 and MF40. After a certain amount of Mv input (22.5 Mg ha^–1), the carbon sequestration rate was affected by the nutrient input due to the stimulation of microbial biomass. Compared with the MF0, the MF100 and MF40 resulted in a dramatically higher carbon sequestration rate (with the value higher by 71.6 and 70.1%), whereas the MF80 induced a lower carbon sequestration rate with the value lower by 70.1% compared to the MF0. Based on the above results we suggested that Mv could partially replace chemical fertilizers (e.g., 40–60%) to improve or maintain the productivity and sustainability of the double-rice cropping system in South-Central China. 展开更多
关键词 CHINESE MILK VETCH fertilizer application levels rice YIELD soil organic carbon double-rice cropping system
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Residual Levels and New Inputs of Chlorinated POPs in Agricultural Soils from Taihu Lake Region 被引量:31
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作者 GAOHong-Jian JIANGXin WANGFang BIANYong-Rong WANGDai-Zhang DENDJian-Cai YANDong-Yun 《Pedosphere》 SCIE CAS CSCD 2005年第3期301-309,共9页
Selected persistent organochlorine pesticides (OCPs), including 1,1,1-trichloro-2,2-bis(p-chlorophenyl)ethane (DDT) and its principal metabolites 1,1-dichloro-2,2-bis(p-chlorophenyl)ethylene (DDE) and 1,1-dichloro-2,2... Selected persistent organochlorine pesticides (OCPs), including 1,1,1-trichloro-2,2-bis(p-chlorophenyl)ethane (DDT) and its principal metabolites 1,1-dichloro-2,2-bis(p-chlorophenyl)ethylene (DDE) and 1,1-dichloro-2,2-bis(p-chlorophenyl)e- thane (DDD), hexachlorocyclohexane (HCH) and its isomers (α-,β-, γ-, and δ-HCH), hexachlorobenzene (HCB), endo- sulfan, dieldrin, and endrin were quantified to determine current levels of organochlorine pesticides, to assess the eco- toxicological potential, and to distin… 展开更多
关键词 agricultural soils chlorinated persistent organic pollutants (POPs) new input residual levels Taihu Lake region
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Design on AM-OLED display control ASIC with high gray scale levels 被引量:4
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作者 季渊 冉峰 +3 位作者 徐洪光 沈伟星 稽维贵 徐美华 《Journal of Shanghai University(English Edition)》 CAS 2011年第4期310-315,共6页
The paper puts forward a method on controlling the AM-OLED panel to display image with high gray scale levels. It also gives an ASIC design sample to implement this method. A twenty sub-fields scan scheme has been tak... The paper puts forward a method on controlling the AM-OLED panel to display image with high gray scale levels. It also gives an ASIC design sample to implement this method. A twenty sub-fields scan scheme has been taken into use in the chip to display 256 gray scale levels on a QVGA resolution AM-OLED display screen. The functions of image scaling and rotating have also been implemented for multiply application. The simulation and chip test result show that the chip design has met the design requirements. 展开更多
关键词 active matrix organic light emitting display (AM-OLED) ASIC design gray scale level sub-field image scaling image rotation
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Zonal Differences in Correlation Patterns Between Soil Organic Carbon and Climate Factors at Multi-extent 被引量:5
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作者 QIN Falyu SHI Xuezheng +2 位作者 XU Shengxiang YU Dongsheng WANG Dandan 《Chinese Geographical Science》 SCIE CSCD 2016年第5期670-678,共9页
Studying the relationship between climate factors and soil organic carbon (SOC) is vitally important. However, how SOC responses to climate (temperature and precipitation) at cohesive extents is poorly studied. Tw... Studying the relationship between climate factors and soil organic carbon (SOC) is vitally important. However, how SOC responses to climate (temperature and precipitation) at cohesive extents is poorly studied. Two transects of approximately the same length (transect P and transect T) were selected to examine the variation of SOC content in relation to mean annual temperature (MAT) and mean annual precipitation (MAP). The coefficients of partial correlation between SOC density and MAT (Rt) and MAP (Rp) were determined to quantify the relationships between SOC density and the two climate factors. The results indicated that for transect T, Rt was statistically significant once the extent level was greater than or equal to two fundamental extent units, while for transect P, Rp showed statistical significance only at extent levels which were greater than two fundamental extent traits. At the same extent levels but in different transects, Rts exhibited no zonal difference, but Rps did once the extent level was greater than two fundamental extent units. Therefore, to study the relationship between SOC density and different climate factors, different minimum extent levels should be ex- amined. The results of this paper could deepen the understanding of the impacts that SOC pool has on terrestrial ecosystem and global carbon cycling. 展开更多
关键词 soil organic carbon (SOC) mean annual temperature (MAT) mean annual precipitation (MAP) extent level coefficient of partial correlation
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Some Investigations on Early Organization of Karst System 被引量:8
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作者 Yu Qingchun(Geofront Laboratory, Department of Civil Engineering, Kyoto University, Kyoto 606-8501, Japan)Shen Jifang Wan Junwei(Department of Hydrogeology and Environmental Engineering, China University of Geosciences,Wuhan 430074, China)Ohnishi Yuzo(Geo 《Journal of Earth Science》 SCIE CAS CSCD 1999年第4期314-321,共8页
Some investigations on the early organization of karst system are carried out through modeling the dissolution evolution processes of stochastic fracture networks in carbonate rock. It is assumed that water flow in fr... Some investigations on the early organization of karst system are carried out through modeling the dissolution evolution processes of stochastic fracture networks in carbonate rock. It is assumed that water flow in fracture network is laminar, and the dissolution rate process can be described with an empirical equation, The results suggest that a karst system is a self-organization system. It can spontaneously create higher hierarchical level out of a relative homogeneous structure through amplifying the microscopic heterogeneity of initial flow field. Under given boundary conditions, a karst system with initial fracture network of varied hierarchical levels is likely to have stronger tendency to lead to a typical karst system featuring conduit passages than a system with initial network of unique hierarchical level. Through merging local flow systems, a karst system concentrates the limited flow into a few pathways to promote the formation of higher hierarchical level. 展开更多
关键词 karst system SELF-organIZATION hierarchical structure hierarchical level
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Paleoecology of Early Ordovician Reefs in the Yichang Area,Hubei:a Correlation of Organic Reefs Between Early Ordovician and Jurassic 被引量:7
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作者 Chuantao XIAO Meng LI +2 位作者 Wei YANG Mingyi HU Chao LI 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2011年第5期1003-1015,共13页
The Early Ordovician System is composed mainly of a series of carbonate platform deposits interbedded with shale and is especially characterized by a large number of organic reefs or buildups that occur widely in the ... The Early Ordovician System is composed mainly of a series of carbonate platform deposits interbedded with shale and is especially characterized by a large number of organic reefs or buildups that occur widely in the research area.The reefs have different thicknesses ranging from 0.5 m to 11.5 m and lengths varying from 1 m to 130 m.The reef-building organisms include Archaeoscyphia, Recepthaculitids,Batostoma,Cyanobacteria and Pulchrilamina.Through the research of characteristics of the reef-bearing strata of the Early Ordovician in the Yichang area,four sorts of biofacies are recognized,which are(1) shelly biofacies:containing Tritoechia-Pelmatozans community and Tritoechia-Pomatotrema community;(2) reef biofacies:including the Batostoma,Calathium-Archaeoscyphia, Pelmatozoa-Batostoma,Archeoscyphia and Calathium-Cyanobacteria communities; (3) standing-water biofacies:including the Acanthograptus-Dendrogptus and Yichangopora communities;and(4) allochthonous biofacies:containing Nanorthis-Psilocephlina taphocoense community.The analysis of sea-level changes indicates that there are four cycles of sea-level changes during the period when reef-bearing strata were formed in this area,and the development of reefs is obviously controlled by the velocity of sea-level changes and the growth of accommodation space.The authors hold that reefs were mostly formed in the high sea level periods.Because of the development of several subordinate cycles during the sea-level rising,the reefs are characterized by great quantity, wide distribution,thin thickness and small scale,which are similar to that of Juassic reefs in northern Tibet.The research on the evolution of communities shows that succession and replacement are the main forms.The former is favorable to the development of reefs and the latter indicates the disappearance of reefs. 展开更多
关键词 organic reef PALEOECOLOGY sea-level change Early Ordovician Yichang area
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Analysis of Micro Organic Compound Pollution in Major City River Reaches of the Main Stem of the Changjiang River
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作者 WANG Che-huaSenior Engineer, Changjiang River Water Environmental Monitoring Center, Wuhan 430051, China PENG BiaoSenior Engineer, Changjiang River Water Environmental Monitoring Center, Wuhan 430051, China 《人民长江》 北大核心 2002年第S1期63-68,共6页
It has become general for surface waters being polluted by micro organic compounds. In order to know the current pollution situation and the properties of micro organic compounds in the Changjiang River, a test was pe... It has become general for surface waters being polluted by micro organic compounds. In order to know the current pollution situation and the properties of micro organic compounds in the Changjiang River, a test was performed on micro organic compounds in the water, bottom material and fish bodies which were sampled from major city river reaches of the Changjiang River. Based on the test result, researchers described and analyzed the sorts, concentration level and distribution features of micro organic compounds. A comprehensive evaluation was conducted by adopting the method of MEG (Multimedia Environmental Goals). The study indicated that ① the water body of major city river reaches of the Changjiang River has been generally polluted. In the test, totally 12 types with 308 kinds of organic compounds were detected. The main pollutants were paraffins, PAHs and lipids; and ② micro organic pollutant content in fish bodies was generally higher than that in bottom material which is in turn higher than that in water; and ③ pollution is relatively severe in the river reaches of mid-to-large comprehensive industrial cities with fairly great TAS (Total Ambient Severity) of public health and ecological system. 展开更多
关键词 MICRO organic compounds content level distribution features water POLLUTION situation MAJOR CITY RIVER reaches main stem of the CHANGJIANG RIVER
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The Complete K-Level Tree and Its Application to Data Warehouse Filtering
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作者 马琳 Wang Kuanquan +1 位作者 Li Haifeng Zucker J D 《High Technology Letters》 EI CAS 2003年第4期13-16,共4页
This paper presents a simple complete K level tree (CKT) architecture for text database organization and rapid data filtering. A database is constructed as a CKT forest and each CKT contains data of the same length. T... This paper presents a simple complete K level tree (CKT) architecture for text database organization and rapid data filtering. A database is constructed as a CKT forest and each CKT contains data of the same length. The maximum depth and the minimum depth of an individual CKT are equal and identical to data’s length. Insertion and deletion operations are defined; storage method and filtering algorithm are also designed for good compensation between efficiency and complexity. Applications to computer aided teaching of Chinese and protein selection show that an about 30% reduction of storage consumption and an over 60% reduction of computation may be easily obtained. 展开更多
关键词 complete K level tree data warehouse organization data filtering data retrieval
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Effects of Plastic Film Mulching on Soil Carbon Fixation Capacity and Fertility Level in Eastern Qinghai
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作者 Kai YANG Qinglan HU Jingui WANG 《Asian Agricultural Research》 2022年第1期60-65,共6页
[Objectives]To explore the effects of single application of chemical fertilizers on soil carbon fixation capacity and soil fertility under plastic film mulching conditions in eastern Qinghai,and to provide a theoretic... [Objectives]To explore the effects of single application of chemical fertilizers on soil carbon fixation capacity and soil fertility under plastic film mulching conditions in eastern Qinghai,and to provide a theoretical basis for realizing the sustainable development of film mulching planting method in this area.[Methods]The effects of single application of chemical fertilizer cultivation mode under film mulching conditions on the soil organic carbon(SOC),labile organic carbon(LOC),carbon management index(CMI),extractable humus carbon(CHE),humic acid carbon(CHA),and fulvic acid carbon(CFA)in the cultivated layer(0-20 cm)were studied through three consecutive years of field experiments on dryland maize farmland in the eastern Qinghai.[Results]Under the film mulching condition,the SOC,LOC and CMI of the single application of chemical fertilizer cultivation mode were lower than that of the open field control.CHE,CHA and CFA increased with the increase of planting years,but the degree of increase was generally less than that of the open field control.With the increase of planting years,by 2020,the soil LOC/SOC value of film mulching decreased by 4.97%compared with before the start of the experiment,while the open field control increased by 1.11%;the organic carbon oxidation stability coefficient(KOS)of the film mulching was higher than that of the open field control;the soil CHA/CFA value and PQ value were higher than that of the open field control.[Conclusions]Under the condition of single application of chemical fertilizers,the continuous film mulching cultivation mode reduces the soil carbon fixation capacity,and soil organic carbon tends to be stable,which is not conducive to biological utilization and could reduce the soil fertility and degrade the soil quality,causing adverse effects on the stability of crop yield and sustainable production in the long run. 展开更多
关键词 SOIL Carbon fixation capacity Fertility level organic carbon HUMUS Plastic film mulching
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农村基层党组织组织力的系统化运作及其提升策略 被引量:2
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作者 颜德如 张爽 《探索》 CSSCI 北大核心 2024年第1期65-78,共14页
从政治系统来审视农村基层党组织,其具备系统的整体属性和运作体系,组织力表现为系统内外各要素有机结合的整体力量。在政治系统论的分析框架下,一方面,农村基层党组织系统的复杂多样易引发组织力的滞后困顿,出现组织力困境;另一方面,... 从政治系统来审视农村基层党组织,其具备系统的整体属性和运作体系,组织力表现为系统内外各要素有机结合的整体力量。在政治系统论的分析框架下,一方面,农村基层党组织系统的复杂多样易引发组织力的滞后困顿,出现组织力困境;另一方面,农村基层党组织以独特的政治优势规范了“输入—转换—输出”的系统运作流程,通过与内外部环境的多维互动和功能互补形成反馈闭环,构成一体化的循环链,由此决定了持续提升农村基层党组织组织力是一项动态的系统工程。解析农村基层党组织的领导与运行工作,其在现实生活中仍然面临内外部因素共同刺激而导致的领导力弱化、凝聚力式微、执行力失范和服务力缺位之困境,组织力水平尚未达到全面推进乡村振兴战略的系统性目标要求,这进一步倒逼农村基层党组织从各个环节入手构建提升组织力的有效策略:政治系统“输入”环节调动“党性—结构—民意”的整合性,政治系统“转换”“输出”环节激活“集成—巩固—共生”的驱动性,政治系统“反馈”环节释放“价值—功能—制度”的交互性。上述策略统筹保障组织的系统化运作及其组织力整合后的正向提升,进而为中国共产党基层治理的持续性发展提供实践遵循。 展开更多
关键词 农村基层党组织 组织力 系统化运作 提升策略
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冲突层级与国际非政府组织参与冲突调停的效力分析 被引量:1
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作者 周亦奇 徐毅 《国际安全研究》 CSSCI 北大核心 2024年第1期136-162,166,共28页
冷战结束后,国内冲突逐步成为世界武装冲突的主要形式之一,而冲突调解是构建冲突国国内和平的关键一环。伴随着和平建构主题的多元性,国际非政府组织逐步成为当今时代各类冲突中活跃的调解主体。然而,国际非政府组织的调停实效始终备受... 冷战结束后,国内冲突逐步成为世界武装冲突的主要形式之一,而冲突调解是构建冲突国国内和平的关键一环。伴随着和平建构主题的多元性,国际非政府组织逐步成为当今时代各类冲突中活跃的调解主体。然而,国际非政府组织的调停实效始终备受争议。一方面,国际非政府组织宣称可凭借其在中立性、道义性上的优势对国内冲突进行有效调停;另一方面,强制能力的缺乏也使其难以在实施环节有所作为。因此,研究国际非政府组织在调停过程中的成功与失败,界定冲突层级,对于理解国际非政府组织的调解效力至关重要。不同层级的冲突顺应不同的冲突逻辑,不同的冲突逻辑则生发不同的冲突情境与格局。在底层冲突中,碎片化和多元主体并存的冲突格局更适合国际非政府组织的运作;而在顶层冲突中,其强制能力不足的缺点遭到放大。基于这一逻辑,在调解活动中与主权国家展开合作则有望强化其调解效力。通过对非洲和平进程展开的实证研究说明,评价国际非政府组织的调解效果特别是在非洲地区的调解效果需要考虑冲突层级等限定条件,并将其与多元主体的互动纳入考量范围。国际非政府组织在冲突调停中应与主权国家的调停体系进行密切配合,在维护国家主权与国际体系稳定的前提下,整合主权国家、国际非政府组织等多方治理行为体的作用,可有效地提升冲突调停的可能性。 展开更多
关键词 冲突调停 和平进程 国际非政府组织 冲突层级
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高校高水平运动队建设路径的逻辑辨识与行动方略——基于行政型体育组织的考察 被引量:1
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作者 周丽君 冯祎晗 《体育学刊》 CAS CSSCI 北大核心 2024年第1期118-124,共7页
从组织管理过程的基本属性行政化入手,依托结构功能主义与组织行为学观点,以个体行动作为逻辑起点,对我国高校高水平运动队实践样态加以剖判并进行类型学建构,归纳其在宏观、中观和微观层面的3类建设路径,由此判辨各路径在建设过程中存... 从组织管理过程的基本属性行政化入手,依托结构功能主义与组织行为学观点,以个体行动作为逻辑起点,对我国高校高水平运动队实践样态加以剖判并进行类型学建构,归纳其在宏观、中观和微观层面的3类建设路径,由此判辨各路径在建设过程中存在的问题,再结合“制度-利益-观念”概念性框架对其进行消解,进而探索高校高水平运动队未来的行动方略。研究认为,我国高校高水平运动队主要呈现出“层层加码”“水平比码”“主体择码”3类建设路径,且分别存在制度环境的行政力量产生锁入效应、高校职能部门间利益分配的非帕累托改变、行政官员对多重建设目标的选择偏颇问题,而这可从制度的规范引导、利益的有效激励和观念的柔性约束3个方面对其进行改善。 展开更多
关键词 高校高水平运动队 行政型体育组织 结构功能主义 组织行为学
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周期性水位波动对三峡水库消落带土壤有机碳含量和密度的影响
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作者 王鹏 冉义国 +3 位作者 梅渝 马茂华 黄平 吴胜军 《土壤》 CAS CSCD 北大核心 2024年第3期672-680,共9页
为探究水位波动对三峡水库消落带土壤有机碳的影响,在三峡水库消落带采集和测定了受不同水淹强度影响的石灰土、紫色土、黄壤及其植物样品,并运用Kruskal-Wallis非参数检验和基于冗余分析的典范分析等方法进行了研究。结果表明:周期性... 为探究水位波动对三峡水库消落带土壤有机碳的影响,在三峡水库消落带采集和测定了受不同水淹强度影响的石灰土、紫色土、黄壤及其植物样品,并运用Kruskal-Wallis非参数检验和基于冗余分析的典范分析等方法进行了研究。结果表明:周期性水淹增加了石灰土和紫色土的有机碳含量和密度,但降低了黄壤的有机碳含量和密度。此外,石灰土的有机碳分布还受地上生物量、土壤pH和土层深度的影响,紫色土的有机碳分布还受土层深度和地上生物量的影响,而黄壤的有机碳含量和密度则与地上生物量、土层深度和地下生物量有关。总之,周期性水位波动对消落带土壤有机碳影响深刻,但土壤类型分异了有机碳对水位波动的响应。 展开更多
关键词 三峡水库 消落带 土壤有机碳 有机碳密度
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