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Analyzing the Design and Promotion of Ideological and Political Content in Online Finance and Economics Courses
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作者 Xiaojie Peng Jun Liu +1 位作者 Xianwei Meng Jianxiang Zhang 《Journal of Contemporary Educational Research》 2022年第7期31-35,共5页
In the context of the new media age,the emergence and development of finance and economics courses along with online course resources have greatly enriched the presentation of teaching resources in colleges and univer... In the context of the new media age,the emergence and development of finance and economics courses along with online course resources have greatly enriched the presentation of teaching resources in colleges and universities.However,subjected to the flawed design and poor promotion of ideological and political contents,which are less popular,online finance and economics courses often do not reflect the meaning well or maximize the application of the courses’ideological and political reform.This paper explores the dilemma and reasons for the promotion of the courses’ideological and political content,in hope to provide suggestions for the design and promotion of ideological and political content in online finance and economics courses in colleges and universities. 展开更多
关键词 Online courses Finance and economics Ideological and political content design and promotion
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Analysis on Variation of Soil Organic Carbon and Total Nitrogen Content and Carbon Storage in the Oasis Cotton Field of Manas River Valley
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作者 雷军 雷子莹 +1 位作者 林海荣 赵瑞海 《Agricultural Science & Technology》 CAS 2014年第3期499-502,共4页
Objective] The research aimed to study soil organic carbon and total ni-trogen distribution in oasis cotton farmland. [Method] With the oasis cotton field of Manas River Val ey in Tianshan Mountains as the research ar... Objective] The research aimed to study soil organic carbon and total ni-trogen distribution in oasis cotton farmland. [Method] With the oasis cotton field of Manas River Val ey in Tianshan Mountains as the research area and abandoned farmland as a control, the distribution characteristics of soil organic carbon and total nitrogen content in the cotton field of Manas River Val ey in the last 23 years were investigated by using geographic methods. [Result] Presenting vertical distribution, cotton soil organic carbon and total nitrogen content in Manas River Val ey de-creased with the increase of soil depth, and those in 0-30 cm soil layer was sig-nificantly higher than those in soil layer of below 30 cm, while organic carbon stor-age showed the trend of increase. Also in vertical distribution, soil organic carbon and total nitrogen decreased significantly with the increase of soil depth, and soil organic carbon content in abandoned farmland decreased month by month. Howev-er, cotton soil organic carbon storage firstly decreased and then increased in the oasis cotton field that in the early growth of cotton, soil organic carbon in the layers of 0-30 and 30-100 cm decreased to the lowest in the bloom stage, and then or-ganic carbon increased with the reproductive growth of cotton into the later stages. However, due to no input of plant litter in the abandoned farmland, the soil organic carbon storage decreased month by month. There were significantly differences be-tween oasis cotton field and abandoned farmland in organic carbon contents. [Con-clusion] The soil organic carbon content and total nitrogen content in oasis cotton field were significantly higher than those in the abandoned farmland. The soil organ-ic carbon storage increased in the layer of 0-30 cm, while there was no significant change of soil organic carbon and total nitrogen content in the layer of 30-100 cm, which was consistent with the previous study on the distribution characteristics of soil organic carbon and total nitrogen content profile. 展开更多
关键词 Oasis cotton field Soil organic carbon Total nitrogen content Soil or-ganic carbon storage
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A Study on the Evolution of Labor Self-Organizations and the Design of Governmental Mechanism from A Complex Network Perspective
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作者 Xu Qingqing Lu Lan +1 位作者 Liu Pengcheng Yi Xin 《Contemporary Social Sciences》 2019年第4期143-155,共13页
Self-organization theory informs an analysis on the evolution of labor self-organizations (LSOs), but lacks technical analysis on the evolution of their organizational structures. Fortunately, complex network technolo... Self-organization theory informs an analysis on the evolution of labor self-organizations (LSOs), but lacks technical analysis on the evolution of their organizational structures. Fortunately, complex network technology offers a new approach to analyzing these structures. Built on an extension of the Barabási-Albert (BA) model, we can simulate the evolution of LSOs by analyzing indicators including the clustering coefficient, degree distribution (DD) and average path length (APL) of workers, thereby demonstrating the evolving patterns of LSOs. Accordingly, governmental mechanism designs based on such patterns may not only stimulate energy growth and functional realization of LSOs, but also reduce the social percussions of abrupt evolutions. A comparative analysis of the evolutionary trajectories of LSOs in China and the U.S. finds that the U.S. government’s mechanism designs for protecting capitalism not only prevented the effective gathering of workers, but also prolonged the history of industrial conflicts. Such mechanism designs also led to the early dispersion and decline of LSOs and hindered the evolution of the working class. In contrast, the Chinese government established a socialist system that allowed workers to become the underlying force of socialist productivity. This design reduced labor strife while accelerating the evolution of workers towards higher stages. 展开更多
关键词 Complex networks (CNs) SELF-organization EVOLUTION mechanism design
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Analysis of the Brand Visual Needs System from the Perspective of Contemporary Market Demands
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作者 Yuanfang Gao Qian Rong 《Journal of Contemporary Educational Research》 2024年第6期22-35,共14页
Brand visual design is not only an essential bridge for companies to convey their ideas and values but also a key factor in shaping the brand image and enhancing market competitiveness.However,a pervasive concern has ... Brand visual design is not only an essential bridge for companies to convey their ideas and values but also a key factor in shaping the brand image and enhancing market competitiveness.However,a pervasive concern has arisen in society that many recent graduates in brand design and visual design cannot immediately meet the demands of the design industry.Despite attempts by scholars to reform courses and teaching philosophies,there are still significant shortcomings and gaps.Therefore,based on market orientation and supply-demand concepts,this study collected in-depth recruitment demands for brand design from 74 companies and conducted systematic summarization and analysis.It synthesized a demand model consisting of three major modules and 55 content points required by companies for brand design students.Based on these demands,adjustments and plans were made to the curriculum content,aiming to construct a teaching system that not only meets market demands but also enhances students’comprehensive qualities.The goal is to cultivate more outstanding talents capable of quickly adapting to and excelling in brand design work. 展开更多
关键词 Brand design design requirements Course content Enterprise needs
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Water,organic matter,nitrogen and phosphorus contents in sediment of a large-scale mariculture area in the Zhelin Bay of eastern Guangdong Province,China 被引量:6
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作者 DONG Qiaoxiang LIN Junda +2 位作者 SHANG Xu LI Jin HUANG Changjiang 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2008年第2期133-148,共16页
The Zhelin Bay is one of the most important bays for large-scale mariculture in Guangdong Province, China. Owing to the increasing human population and the expanding mariculture in the last two decades, the ecological... The Zhelin Bay is one of the most important bays for large-scale mariculture in Guangdong Province, China. Owing to the increasing human population and the expanding mariculture in the last two decades, the ecological environment has greatly changed with frequent harmful algal blooms. A monthly survey of water content, organic matter (TOM), and various forms of nitrogen and phosphorous in sediment from July 2002 to July 2003 in the bay was conducted. The results showed that the water content was correlated significantly with TOM and various forms of nitrogen and phosphorus and can be used as proxy for quick and rough estimate of these factors in the future surveys. TOM was also correlated significantly with various forms of nitrogen and phosphorus, indicating that it was one of the key factors affecting the concentrations and distributions of nitrogen and phosphorus in the investigated waters. Average total Kjeldhal nitrogen (TkN) content was( 1 113.1 ± 382.5)μg/g and average total phosphorus (TP) content was(567.2± 223.3)μg/g, and both were much higher than those of similar estuaries in China and elsewhere. Average nitrogen and phosphorus tended to be higher inside than outside the bay, higher at aquaculture than non-aquaculture areas, and higher at fish-cage culture than oyster culture areas, suggesting that large-scale mariculture inside the bay played an important role in the eutrophication of the Zhelin Bay. Various forms of nitrogen and phosphorus concentrations were higher during the warm season (July--September), which was due to the increased decomposition and concentration of organic matter resulted from the fast growth and high mortality of the cultured species. Compared with July 2002, TkN and TP contents were much higher in July 2003, in consonance with the eutrophication of the Zhelin Bay. Because exchangeable phosphorus (Ex-P), iron-bounded phos- phorus (Fe-P) and organic phosphorus (OP) combined accounted for 34.3% of the TP and authigenic phosphorus (Au-P) accounted for 49.2% of the TP, biological phosphorus (BP) that includes Ex-P, Fe-P, OP, and a portion of Au-P, thus accounted for 34.3% to 83.5% of the TP in the Zhelin Bay, which was within the percentage range, but with a high absolute value among the estuaries. Au-P was the most important species of phosphorus and accounted for 49.2% of the TP during the investigation. Since eutrophication in the water column can lead to reduction of pH in sediment and release of phosphorus in Au-P combined with authigenic spodiosite and calcium carbonate, high content of Au-P in the sediment maybe act as a time bomb that can trigger a vicious cycle of eutrophication and large-scale harmful algal bloom in the Zhelin Bay. 展开更多
关键词 Zhelin Bay SEDIMENT NITROGEN PHOSPHORUS water content organic matter
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New Hybrid AD Methodology for Minimizing the Total Amount of Information Content:A Case Study of Rehabilitation Robot Design 被引量:4
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作者 Tao Yang Xueshan Gao Fuquan Dai 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2020年第6期177-186,共10页
Converting customer needs into specific forms and providing consumers with services are crucial in product design.Currently,conversion is no longer difficult due to the development of modern technology,and various mea... Converting customer needs into specific forms and providing consumers with services are crucial in product design.Currently,conversion is no longer difficult due to the development of modern technology,and various measures can be applied for product realization,thus increasing the complexity of analysis and evaluation in the design process.The focus of the design process has thus shifted from problem solving to minimizing the total amount of information content.This paper presents a New Hybrid Axiomatic Design(AD)Methodology based on iteratively matching and merging design parameters that meet the independence axiom and attribute constraints by applying trimming technology,the ideal final results,and technology evolution theory.The proposed method minimizes the total amount of information content and improves the design quality.Finally,a case study of a rehabilitation robot design for hemiplegic patients is presented.The results indicate that the iterative matching and merging of related attributes can minimize the total amount of information content,reduce the cost,and improve design efficiency.Additionally,evolutionary technology prediction can ensure product novelty and improve market competitiveness.The methodology provides an excellent way to design a new(or improved)product. 展开更多
关键词 Axiomatic design Amount of information content TRIMMING Rehabilitation robot
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Identifying the influence of urbanization on soil organic matter content and p H from soil magnetic characteristics 被引量:4
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作者 YANG Han XIONG Heigang +2 位作者 CHEN Xuegang WANG Yaqi ZHANG Fang 《Journal of Arid Land》 SCIE CSCD 2015年第6期820-830,共11页
Soil magnetic characteristics are correlated with soil p H and organic matter content. Analyzing soil magnetic characteristics, organic matter content and p H can indirectly evaluate soil pollution caused by human act... Soil magnetic characteristics are correlated with soil p H and organic matter content. Analyzing soil magnetic characteristics, organic matter content and p H can indirectly evaluate soil pollution caused by human activities. This study analyzed the soil magnetic characteristics, organic matter content and p H in surface soil samples from different land use types in Shihezi city, a newly and rapidly developing oasis city in Xinjiang of China. The aims of this study were to explore the possible relationships among the soil magnetic parameters and thereby improve the understanding of influence of urbanization on soil properties. Eighty surface soil samples at the depth of 0–10 cm were collected from 29 July to 4 August 2013. The results showed that the magnetic minerals in surface soil were dominated by ferromagnetic minerals. Spatially, the magnetic susceptibility(χLF), anhysteretic remanent magnetization susceptibility(χARM), saturation isothermal remanent magnetization(SIRM) and "soft" isothermal remanent magnetization(SOFT) were found to be most dominant in the new northern urban area B(N-B), followed by built-up areas(U), suburban agricultural land(F), and then the new northern urban area A(N-A). The values of χLF, χARM, SIRM and SOFT were higher in the areas with high intensities of human activities and around the main roads. Meanwhile, the property "hard" isothermal remanent magnetization(HIRM) followed the order of U〉N-B〉F〉N-A. Built-up areas had an average p H value of 7.93, which was much higher than that in the new northern urban areas as well as in suburban agricultural land, due to the increased urban pollutant emissions. The average value of soil organic matter content in the whole study area was 34.69 g/kg, and the values in the new northern urban areas were much higher than those in the suburban agricultural land and built-up areas. For suburban agricultural land, soil organic matter content was significantly negatively correlated with χLF, and had no correlation with other magnetic parameters, since the soil was frequently ploughed. In the new northern urban areas(N-A and N-B), there were significant positive correlations of soil organic matter contents with χARM, SIRM, SOFT and HIRM, because natural grasslands were not frequently turned over. For the built-up areas, soil organic matter contents were significantly positively correlated with χLF, χARM, SIRM and SOFT, but not significantly correlated with frequency-dependent susceptibility(χFD, expressed as a percentage) and HIRM, because the soil was not frequently turned over or influenced by human activities. The results showed that soil magnetic characteristics are related to the soil turnover time. 展开更多
关键词 environmental magnetism surface soil p H soil organic matter content
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The Relationship Between Plant Community Characteristics and Soil Organic Matter Content of Sedentary Grazing Pastures in a Typical Steppe 被引量:1
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作者 SARULA SAIXIYALATU +1 位作者 CHUN Feng ZHANG Weiqing 《Journal of Landscape Research》 2019年第1期57-60,64,共5页
In order to discuss the relationship between the characteristics of plant communities and the content of topsoil organic matter under the condition of two-season sedentary grazing, authors of this paper selected a Sti... In order to discuss the relationship between the characteristics of plant communities and the content of topsoil organic matter under the condition of two-season sedentary grazing, authors of this paper selected a Stipa krylovii steppe for research and studied the plant community characteristics and the topsoil organic matter content. The results showed that in the sedentary grazing area, the perennial plant species decreased, the annual plant species increased, and the topsoil organic matter content decreased. There were a negative correlation between plant biomass and topsoil organic matter content, and a positive correlation between total coverage and topsoil organic matter content. The change of plant community characteristics in the sedentary grazing area was related to the implementation of the system of transferring the pasture use rights to the herdsmen and controlled grazing. 展开更多
关键词 STIPA krylovii STEPPE Plant community characteristics Soil organic matter content SEDENTARY GRAZING
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Opto-thermal Moisture Content and Moisture Depth Profile Measurements in Organic Materials
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作者 XIAOPeng GUOXin-xin +2 位作者 CUIYing-xin RobertE.Imhof DaneBicanic 《Chemical Research in Chinese Universities》 SCIE CAS CSCD 2004年第4期417-420,共4页
Opto-thermal transient emission radiometry(OTTER) is a infrared remote sensing technique, which has been successfully used in in vivoskin moisture content and skin moisture depth profiling measurements. In present pap... Opto-thermal transient emission radiometry(OTTER) is a infrared remote sensing technique, which has been successfully used in in vivoskin moisture content and skin moisture depth profiling measurements. In present paper, we extend this moisture content measurement capability to analyze the moisture content of fruit(tomato, grape, etc.) skins, and to study the relationship between fruits ripening process and their surface moisture and moisture depth profiles. 展开更多
关键词 LASER Opto-thermal radiometry INFRARED Moisture content Depth profiling Organic material
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The effects of soil sand contents on characteristics of humic acids along soil profiles
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作者 Xinyue Di Hui Dong +2 位作者 Xianjin An Haiming Tang Baohua Xiao 《Acta Geochimica》 EI CAS CSCD 2016年第3期251-261,共11页
It is generally accepted that the compositions and properties of soil organic matter (SOM) are influenced by many factors. In order to reveal the effects of soil texture on characteristics and dynamics of SOM and it... It is generally accepted that the compositions and properties of soil organic matter (SOM) are influenced by many factors. In order to reveal the effects of soil texture on characteristics and dynamics of SOM and its sub-fraction, humic acid (HA), along two soil profiles, a yellow soil profile and a purplish soil profile, under the same climate and vegetation conditions were determined. Results indi- cate that the decomposition and humification degrees of SOM and HA of the purplish soils are higher than those of the corresponding yellow soils indicated by A/O-A ratios of HAs, TOCs and HA yields of bulk soil samples, neverthe- less, the development degree of the purplish soil is lower than that of the yellow soil. The variations of E4/E6 ratios of HAs along the soil profiles indicate the overall molecular sizes of HAs decreased downward along the soil profiles. A/O-A ratios of HAs decreased downward along both the soil profiles indicate that humification processes decrease downward along both the soil profiles. Leaching of SOM shows significant effects on the distribution and character- istics of HAs in the yellow soil profile but the purplish soil profile, which is consistent with the higher hydrophobicity of HAs in purplish soils, shows that the distribution char- acteristics of SOM along the soil profiles are a complex result of the combination of soil texture and characteristics of SOM itself. The remarkably different sand contents are concluded tentatively as one of reasons to the differentdistributions and dynamics of HAs along the soil profiles, however, to profoundly understand the evolution and transport of SOM along soil profiles needs more researches. 展开更多
关键词 Soil profile Soil organic matter Humic acid CHARACTERISTICS Sand content
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Meta-model Based Model Organization and Transformation of Design Pattern Units in MDA
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作者 杨长春 赵子艺 孙婧 《Journal of Measurement Science and Instrumentation》 CAS 2010年第2期183-187,共5页
To achieve the purpose of applying design patterns which are various in ldnd and constant in changing in MDA from idea and application, one way is used to solve the problem of pattern disappearance which occurs at the... To achieve the purpose of applying design patterns which are various in ldnd and constant in changing in MDA from idea and application, one way is used to solve the problem of pattern disappearance which occurs at the process of pattern instantiation, to guarantee the independence of patterns, and at the same time, to apply this process to multiple design pattems. To solve these two problons, the modeling method of design pattern traits based on meta-models is adopted, i.e., to divide the basic operations into atoms in the metamodel tier and then combine the atoms to complete design pattem units meta-models withtout business logic. After one process of conversion, the purpose of making up various pattem traits meta-model and dividing business logic and pattern logic is achieved. 展开更多
关键词 MDA PIM design pattern model organization
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BPSCCO Superconducting Films Grown by Spray Pyrolysis Technique: Systematic Study of the Relationship between Pb Content and Annealing Conditions
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作者 Y Elvia Díaz Valdés Concepción Mejía García +1 位作者 Ana María Paniagua Mercado Arturo Méndez Sánchez 《Advances in Materials Physics and Chemistry》 2012年第4期92-95,共4页
Actually recent investigation in developing semiconducting-superconducting composites based in CdS and Bi-based superconductors has attracted interest in processing thin superconducting films. In this work are reporte... Actually recent investigation in developing semiconducting-superconducting composites based in CdS and Bi-based superconductors has attracted interest in processing thin superconducting films. In this work are reported Bi-Pb-Sr-Ca-Cu-O (BPSCCO) thin films grown on MgO substrates by spray pyrolysis technique from a solution containing Bi(NO3)3, Pb(NO3)2, Sr(NO3)2, Ca(NO3)2 and Cu(NO3)2, with a subsequent solid state reaction for growing the Bi-based superconducting phases. Annealed films were characterized by X-ray diffraction, atomic absorption spectroscopy and resistance measurements. Interdependence between Pb content, annealing time and temperature, in the formation of superconducting phases was studied applying a fractional factorial design 3III4-2. Interrelation between Pb content, ta and Ta exists. The presence of Pb is necessary to stabilize the high-Tc phase but its content depends on the annealing conditions. 展开更多
关键词 SUPERCONDUCTIVITY BPSCCO SUPERCONDUCTING Films Spray PYROLYSIS Deposition PB content Annealing Conditions Experimental design
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The Design of Treatment Wetlands in the United Kingdom:Successes,Failures,and Alternative Approaches
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作者 SUN Guangzhi ZHANG Guangxin 《湿地科学》 CSCD 2008年第2期343-350,共8页
Constructed wetland was first introduced into the United Kingdom in the middle of 1980s,following a visit by a group of scientist to Western Germany.In the past 2 decades,the applications of constructed wetlands in th... Constructed wetland was first introduced into the United Kingdom in the middle of 1980s,following a visit by a group of scientist to Western Germany.In the past 2 decades,the applications of constructed wetlands in this country have expanded substantially,due to the demand for green technologies and rising cost of fossil fuel energies.This paper reported a statistical investigation of the performances of 78 horizontal flow wetlands,representatives of such system in the United Kingdom.Alternative design equations,based on organic matter removal efficiency,have been developed from Monod kinetics,and the accuracy and reliability of current and alternative design approaches have been examined. 展开更多
关键词 湿地保护 环境保护 治理措施 水土流失
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Step‑by‑Step Modulation of Crystalline Features and Exciton Kinetics for 19.2%Efficiency Ortho‑Xylene Processed Organic Solar Cells 被引量:1
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作者 Bosen Zou Weiwei Wu +10 位作者 Top Archie Dela Pena Ruijie Ma Yongmin Luo Yulong Hai Xiyun Xie Mingjie Li Zhenghui Luo Jiaying Wu Chuluo Yang Gang Li He Yan 《Nano-Micro Letters》 SCIE EI CAS CSCD 2024年第2期258-272,共15页
With plenty of popular and effective ternary organic solar cells(OSCs)construction strategies proposed and applied,its power conversion efficiencies(PCEs)have come to a new level of over 19%in single-junction devices.... With plenty of popular and effective ternary organic solar cells(OSCs)construction strategies proposed and applied,its power conversion efficiencies(PCEs)have come to a new level of over 19%in single-junction devices.However,previous studies are heavily based in chloroform(CF)leaving behind substantial knowledge deficiencies in understanding the influence of solvent choice when introducing a third component.Herein,we present a case where a newly designed asymmetric small molecular acceptor using fluoro-methoxylated end-group modification strategy,named BTP-BO-3FO with enlarged bandgap,brings different morphological evolution and performance improvement effect on host system PM6:BTP-eC9,processed by CF and ortho-xylene(o-XY).With detailed analyses supported by a series of experiments,the best PCE of 19.24%for green solvent-processed OSCs is found to be a fruit of finely tuned crystalline ordering and general aggregation motif,which furthermore nourishes a favorable charge generation and recombination behavior.Likewise,over 19%PCE can be achieved by replacing spin-coating with blade coating for active layer deposition.This work focuses on understanding the commonly met yet frequently ignored issues when building ternary blends to demonstrate cutting-edge device performance,hence,will be instructive to other ternary OSC works in the future. 展开更多
关键词 Organic solar cells Ternary design Solvent selection Flouro-methoxylated end group Morphological ordering
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Characterization of the Songhua River sediments and evaluation of their adsorption behavior for nitrobenzene 被引量:15
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作者 Liu Ruiping Liu Huijuan +1 位作者 Wan Dongjin Yang Min 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2008年第7期796-802,共7页
The explosion at a plant of the Jilin Petrochemical Corporation on 13 November,2005,and the spill of an estimated 100 t of toxic substances (nitrobenzene as the main component) into the Songhua River received worldwid... The explosion at a plant of the Jilin Petrochemical Corporation on 13 November,2005,and the spill of an estimated 100 t of toxic substances (nitrobenzene as the main component) into the Songhua River received worldwide attention.This study has focused on the adsorption behavior of nitrobenzene that spilled onto sediments along the Songhua River,which was one of the efforts to evaluate the fate of nitrobenzene after the spillage event.The organic carbon contents of these sediments along the Songhua River var... 展开更多
关键词 NITROBENZENE ADSORPTION sediment characteristics organic carbon content particle size distribution
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Effects of salinity on the soil microbial community and soil fertility 被引量:9
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作者 ZHANG Wen-wen WANG Chong +1 位作者 XUE Rui WANG Li-jie 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2019年第6期1360-1368,共9页
Saline area is an important reserve resource of arable land,however,the effects of soil microorganisms on the soil fertility in saline coastal ecosystems remain poorly understood.The salinity effects on soil microorga... Saline area is an important reserve resource of arable land,however,the effects of soil microorganisms on the soil fertility in saline coastal ecosystems remain poorly understood.The salinity effects on soil microorganisms,nutrient availabilities and their relationships were studied in soils along a salinity gradient.A total of 80 soil samples were collected from 16 sites at four salinity levels(non-saline soil,salt content<1 g kg^1;low salinity soil,salt content=1–2 g kg^1;middle salinity soil,salt content=2–4 g kg^1;high salinity soil,salt content>4 g kg^1).The results showed that the salinity increased soil pH and exchangeable Na percent,but decreased soil organic matter,soil exchangeable K,and soil microbial biomass.Both the abundance and community composition of soil bacteria and fungi were significantly different between the non-saline and the saline soils.The predominant genera of soil bacteria(Planctomyces and Archangium,positive for carbon fixation)and fungi(Hydropisphaera,efficient in lignin degradation)changed with the increasing soil salinity and the decreasing soil organic matter.In summary,soil salinity changed the abundances of soil bacterial,fungal,and arbuscular mycorrhizal communities and,subsequently,affected their function in saline coastal ecosystems. 展开更多
关键词 SOIL SALT content SOIL organic MATTER T-RFLP SOIL health
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Soil Organic Carbon Content and Distribution in a Small Landscape of Dongguan, South China 被引量:22
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作者 SU Zhi-Yao XIONG Yong-Mei +2 位作者 ZHU Jian-Yun YE Yong-Chang YE Mai 《Pedosphere》 SCIE CAS CSCD 2006年第1期10-17,共8页
Global warming has become an increasing concern, and using soil as a carbon sink to sequester carbon dioxide has attracted much attention in recent years. In this study, soil organic carbon (SOC) content and organic c... Global warming has become an increasing concern, and using soil as a carbon sink to sequester carbon dioxide has attracted much attention in recent years. In this study, soil organic carbon (SOC) content and organic carbon density were estimated based on a soil survey of a small landscape in Dongguan, South China, with spatial heterogeneity of SOC distribution and the impacts of land-use patterns on soil organic carbon content assessed. Field sampling was carried out based on a 150 m×150 m grid system overlaid on the topographic map of the study area and samples were collected in three 20-cm layers to a depth of 60 cm. Spatial variability in the distribution of SOC was assessed using the Kruskal-Wallis test. Results showed that SOC in the topsoil layer (0-20 cm) was not much higher or even lower in some sites than the underlying layers, and except for the two sites covered with natural woodland, it did not exhibit a pronounced vertical gradient. The difference in both horizontal and vertical distribution of SOC was not statistically significant. However, in the topsoil layer among land-use/land-cover patterns, significant differences (P≤0.05) in SOC distribution existed, indicating that management practices had great impact on SOC content. SOC storage in the study area to a depth of 20, 40, and 60 cm was estimated as 2.13×106 kg, 3.46×106 kg, and 4.61×106 kg, respectively. 展开更多
关键词 land-use pattern organic carbon content organic carbon density spatial wariability
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Discovery and Analysis of Shale Gas in a Carboniferous Reservoir and its Enrichment Characteristics in the Northern Nanpanjiang Depression, Guizhou Province, China 被引量:5
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作者 LU Shufan LUO Xiangjian +3 位作者 DU Shengjiang HE Ben FU Hongbin LIU Kuiyong 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2019年第3期561-572,共12页
Shale gas resources are considered to be extremely abundant in southern China,which has dedicated considerable attention to shale gas exploration in recent years.Exploration of shale gas has considerably progressed an... Shale gas resources are considered to be extremely abundant in southern China,which has dedicated considerable attention to shale gas exploration in recent years.Exploration of shale gas has considerably progressed and several breakthroughs have been made in China.However,shale gas explorations are still scarce.Summary and detailed analysis studies on black shale reservoirs are still to be performed for many areas.This lack of information slows the progress of shale gas explorations and results in low quantities of stored black shale.The Carboniferous Dawuba Formation,which is widely distributed and considerably thick,is one of the black shale formations targeted for shale gas exploration in southern China in the recent years.The acquisition and analysis of total organic carbon,vitrinite reflectance,types of organic matter,mineral composition,porosity,and permeability are basic but important processes.In addition,we analyzed the microscopic pores present in the shale.This study also showesd the good gas content of the Dawuba Formation,as well as the geological factors affecting its gas content and other characteristics.To understand the prospect of exploration,we compared this with other shale reservoirs which have been already successfully explored for gas.Our comparison showesd that those shale reservoirs have similar but not identical geological characteristics. 展开更多
关键词 Nanpanjiang DEPRESSION Dawuba Formation SHALE GAS organic geochemistry RESERVOIR GAS content
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Adaptive optimization of agile organization of command and control resource 被引量:8
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作者 Yang Chunhui Liu Junxian +1 位作者 Chen Honghui Luo Xueshan 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2009年第3期558-564,共7页
Adaptive optimization is one of the means that agile organization of command and control resource (AOC2R) adapts for the dynamic battlefield environment. A math model of the adaptive optimization of AOC2R is put for... Adaptive optimization is one of the means that agile organization of command and control resource (AOC2R) adapts for the dynamic battlefield environment. A math model of the adaptive optimization of AOC2R is put forward by analyzing the interrelating concept and research. The model takes the adaptive process as a multi-stage decision making problem. The 2-phases method is presented to calculate the model, which obtains the related parameters by running the colored Petri net (CPN) model of AOC2R and then searches for the result by ant colony optimization (ACO) algorithm integrated with genetic optimization techniques. The simulation results demonstrate that the proposed algorithm greatly improves the performance of AOC2R. 展开更多
关键词 command and control organization adaptive optimization of organization dynamic-window-search ant colony optimization 3-phase organizational design.
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Elevation and Land Use Types Have Significant Impacts on Spatial Variability of Soil Organic Matter Content in Hani Terraced Field of Yuanyang County,China 被引量:5
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作者 LI Feng-bo LU Guang-de +6 位作者 ZHOU Xi-yue NI Hui-xiang XU Chun-chun YUE Chao YANG Xiu-mei FENG Jin-fei FANG Fu-ping 《Rice science》 SCIE CSCD 2015年第1期27-34,共8页
Soil organic matter (SOM) content is one of the most important indicators of the sustainability of soil. To maintain sustainable soil utilization and management in fragile Hani terraced field, it is meaningful to in... Soil organic matter (SOM) content is one of the most important indicators of the sustainability of soil. To maintain sustainable soil utilization and management in fragile Hani terraced field, it is meaningful to investigate the effects of topography and land use type on SOM content. Descriptive statistics and geostatistics were used to analyze the data and the kriging method was applied to map the spatial patterns of SOM content. The results showed that the mean SOM content was 32.76 g/kg, with a variation coefficient of 40%. The SOM content was affected by elevation and land use type. As the increase of elevation, the SOM content in Hani terraced field also increased obviously. The SOM content in tea garden, which is almost at high elevation, was the highest in all six land use types, and the SOM content decreased in a following sequence: tea garden 〉 paddy field 〉 corn field 〉 banana garden 〉 cassava field 〉 sugarcane field. In addition, at the same elevation, the paddy field had the highest SOM content compared with other land use types. All these results demonstrate that paddy field is the most efficient and suitable land use type for SOM conservation at high, middle or low elevations in the fragile Hani terraced field. In order to protect soil quality and maintain the sustainable agricultural development, it is necessary to maintain or even to enlarge the area of paddy field in Yuanyang county, Yunnan Province, China. 展开更多
关键词 Hani terraced field ELEVATION land use type GEOSTATISTICS soil organic matter content
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