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Fertilization and Soil Ploughing Practices under Changing Physical Environment Lead to Soil Organic Carbon Dynamics under Conservation Agriculture in Rice-Wheat Cropping System: A Scoping Review
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作者 Salwinder Singh Dhaliwal Arvind Kumar Shukla +8 位作者 Sanjib Kumar Behera Sarwan Kumar Dubey Agniva Mandal Mehakpreet Kaur Randhawa Sharanjit Kaur Brar Gagandeep Kaur Amardeep Singh Toor Sohan Singh Walia Priyadarshani Arun Khambalkar 《Agricultural Sciences》 2024年第1期82-113,共32页
Ploughing and fertilization practices in rice-wheat system have deteriorated the soil carbon (C) pools. Conservation agriculture (CA) based management approaches have proven to enhance C sequestration and reverse the ... Ploughing and fertilization practices in rice-wheat system have deteriorated the soil carbon (C) pools. Conservation agriculture (CA) based management approaches have proven to enhance C sequestration and reverse the loss of soil-organic-carbon (SOC), which further enhances soil fertility. Different fractions of SOC pools react to the alterations in management practices and indicate changes in SOC dynamics as compared to total C in the soil. Higher SOC levels in soil have been observed in case of reduced/no-till (NT) practices than conventional tillage (CT). However, between CT and zero tillage/NT, total SOC stocks diminished with an increase in soil depth, which demonstrated that the benefits of SOC are more pronounced in the topsoil under NT. Soil aggregation provides physical protection to C associated with different-sized particles, thus, the improvement in soil aggregation through CA is an effective way to mitigate soil C loss. Along with less soil disturbance, residual management, suitable crop rotation, rational application of manures and fertilizers, and integrated nutrient management have been found to be effective in not only improving soil C stock but also enhancing the soil health and productivity. Thus, CA can be considered as a potential method in the build-up of SOC of soil in rice-wheat system. 展开更多
关键词 TILLAGE Conservation Agriculture Soil organic Carbon Carbon Fractions Rice-Wheat system organic Amendments
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Auxiliary Software for Defining the Parameters of the Structural Organization of a Complex System
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作者 Branislav M. Savic 《Journal of Software Engineering and Applications》 2024年第2期109-128,共20页
The developed auxiliary software serves to simplify, standardize and facilitate the software loading of the structural organization of a complex technological system, as well as its further manipulation within the pro... The developed auxiliary software serves to simplify, standardize and facilitate the software loading of the structural organization of a complex technological system, as well as its further manipulation within the process of solving the considered technological system. Its help can be especially useful in the case of a complex structural organization of a technological system with a large number of different functional elements grouped into several technological subsystems. This paper presents the results of its application for a special complex technological system related to the reference steam block for the combined production of heat and electricity. 展开更多
关键词 Complex system Structural organization Auxiliary Software PARAMETERS
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Impact on Soil Organic C and Total Soil N from Cool- and Warm-Season Legumes Used in a Green Manure-Forage Cropping System
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作者 Clark B. Neely Francis M. Rouquette Jr. +3 位作者 Cristine L.S. Morgan Frank M. Hons William L. Rooney Gerald R. Smith 《Agricultural Sciences》 2024年第3期333-357,共25页
Annual forage legumes are important components of livestock production systems in East Texas and the southeastern US. Forage legumes contribute nitrogen (N) to cropping systems through biological N fixation, and their... Annual forage legumes are important components of livestock production systems in East Texas and the southeastern US. Forage legumes contribute nitrogen (N) to cropping systems through biological N fixation, and their seasonal biomass production can be managed to complement forage grasses. Our research objectives were to evaluate both warm- and cool-season annual forage legumes as green manure for biomass, N content, ability to enhance soil organic carbon (SOC) and soil N, and impact on post season forage grass crops. Nine warm-season forage legumes (WSL) were spring planted and incorporated as green manure in the fall. Forage rye (Secale cereale L.) was planted following the incorporation of WSL treatments. Eight cool-season forage legumes (CSL) were fall planted in previously fallow plots and incorporated as green manure in late spring. Sorghum-sudangrass (Sorghum bicolor x Sorghum bicolor var. sudanense) was planted over all treatments in early summer after forage rye harvest and incorporation of CSL treatments. Sorghum-sudangrass was harvested in June, August and September, and treatments were evaluated for dry matter and N concentration. Soil cores were taken from each plot, split into depths of 0 to 15, 15 to 30 and 30 to 60 cm, and soil C and N were measured using combustion analysis. Nylon mesh bags containing plant samples were buried at 15 cm and used to evaluate decomposition rate of above ground legume biomass, including change in C and N concentrations. Mungbean (Vigna radiata L. [Wilczek]) had the highest shoot biomass yield (6.24 t DM ha<sup>-1</sup>) and contributed the most total N (167 kg∙ha<sup>-1</sup>) and total C (3043 kg∙ha<sup>-1</sup>) of the WSL tested. Decomposition rate of WSL biomass was rapid in the first 10 weeks and very slow afterward. Winter pea (Pisum sativum L. spp. sativum), arrow leaf clover (Trifolium vesiculosum Savi.), and crimson clover (Trifolium incarnatum L.) were the most productive CSL in this trial. Austrian winter pea produced 8.41 t DM ha<sup>-1</sup> with a total N yield of 319 kg N ha<sup>-1</sup> and total C production of 3835 kg C ha<sup>-1</sup>. The WSL treatments had only small effects on rye forage yield and N concentration, possibly due to mineralization of N from a large SOC pool already in place. The CSL treatments also had only minimal effects on sorghum-sudangrass forage production. Winter pea, arrow leaf and crimson clover were productive cool season legumes and could be useful as green manure crops. Mungbean and cowpea (Vigna unguiculata [L.] Walp.) were highly productive warm season legumes but may include more production risk in green manure systems due to soil moisture competition. 展开更多
关键词 Annual Legumes Soil N Soil organic C Green Manure Deer Browse Forage Cropping systems
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基于自由曲面和L-system的红掌生长模型
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作者 邹一波 褚诗贤 +1 位作者 葛艳 陈明 《湖南农业大学学报(自然科学版)》 CAS CSCD 北大核心 2024年第1期85-90,共6页
针对红掌花卉生长可视化中参数难以确定的问题进行研究,提出推导控制点的方法,建立红掌器官模型:采用Bezier曲线结合扫描成型的方法来构造叶柄模型,采用双三次NURBS曲线对佛焰苞进行建模;运用红掌的相关表型数据拟合生长函数,提出基于... 针对红掌花卉生长可视化中参数难以确定的问题进行研究,提出推导控制点的方法,建立红掌器官模型:采用Bezier曲线结合扫描成型的方法来构造叶柄模型,采用双三次NURBS曲线对佛焰苞进行建模;运用红掌的相关表型数据拟合生长函数,提出基于红掌生长规律的微分L-system,可有效模拟红掌的拓扑结构和生长过程;通过虚拟器官表示红掌器官的几何属性,降低微分L-system的复杂度。试验验证提出的方法对红掌各项生长指标拟合度可达0.89以上,并可对每个生长阶段的红掌进行模拟,能有效地对红掌的生长过程进行建模。 展开更多
关键词 红掌 自由曲面建模 L-system 生长函数 虚拟器官
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Applying the Technology Acceptance Model (TAM) in Information Technology System to Evaluate the Adoption of Decision Support System
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作者 Md Azhad Hossain Anamika Tiwari +3 位作者 Sanchita Saha Ashok Ghimire Md Ahsan Ullah Imran Rabeya Khatoon 《Journal of Computer and Communications》 2024年第8期242-256,共15页
With the beginning of the information systems’ spreading, people started thinking about using them for making business decisions. Computer technology solutions, such as the Decision Support System, make the decision-... With the beginning of the information systems’ spreading, people started thinking about using them for making business decisions. Computer technology solutions, such as the Decision Support System, make the decision-making process less complex and simpler for problem-solving. In order to make a high-quality business decision, managers need to have a great deal of appropriate information. Nonetheless, this complicates the process of making appropriate decisions. In a situation like that, the possibility of using DSS is quite logical. The aim of this paper is to find out the intended use of DSS for medium and large business organizations in USA by applying the Technology Acceptance Model (TAM). Different models were developed in order to understand and predict the use of information systems, but the information systems community mostly used TAM to ensure this issue. The purpose of the research model is to determine the elements of analysis that contribute to these results. The sample for the research consisted of the target group that was supposed to have completed an online questionnaire about the manager’s use of DSS in medium and large American companies. The information obtained from the questionnaires was analyzed through the SPSS statistical software. The research has indicated that, this is primarily used due to a significant level of Perceived usefulness and For the Perceived ease of use. 展开更多
关键词 Information Technology Decision Support system Business organization in USA Technology Acceptance Model
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Soil Organic Carbon and Nitrogen Dynamics in Arabica Coffee Agroforestry Systems in the Noun Division, West Cameroon
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作者 Abdel Malik Atoupka Emile Temgoua +2 位作者 Lucie Félicité Temgoua Jean Baurel Atchombou Steve Tassiamba 《Open Journal of Forestry》 2023年第3期262-277,共16页
Agroforestry systems (AFSs) offer viable solutions to climate change because of the below-ground biomass (BGB) that is maintained by the soil. Therefore, spatially explicit estimation of their BGB is crucial to accoun... Agroforestry systems (AFSs) offer viable solutions to climate change because of the below-ground biomass (BGB) that is maintained by the soil. Therefore, spatially explicit estimation of their BGB is crucial to account for emission reduction efforts. A study to assess soil organic carbon (SOC) and nitrogen dynamics in Arabica coffee agroforests was conducted in two subdivisions (Foumbot and Kouoptamo) of the Noun Division in western Cameroon. The methodological approach involved the collection of 150 soil samples taken at different depths: 0 - 10, 10 - 20 and 20 - 30 cm. Depending on the depth, the SOC stock is 27.93 ± 1.13 tC/ha at 10 cm depth, 22.37 ± 1.47 tC/ha at 20 cm and 20.79 ± 0.31 tC/ha at 30 cm. According to the age classes of the Arabica coffee systems (ACA), the C/N ratio in our study area averaged 26.94 ± 13.60 for the (5 - 20) year old systems in Foumbot and 60.64 ± 48.80 for the (20 - 35) year old systems in Kouoptamo. Depending on the depth, at 10 cm this ratio is higher in Kouoptamo than in Foumbot with a maximum value of 57 and 38 respectively for the two subdivisions. In view of the results obtained, it would be important to analyse the types of microorganisms responsible for the decomposition of organic matter which is linked to soil organic carbon. 展开更多
关键词 Agroforestry systems Coffee Trees Soil organic Carbon Noun Division West Cameroon
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Analysis of diffusion-adsorption equivalency of landfill liner systems for organic contaminants 被引量:9
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作者 XIE Haijian, CHEN Yunmin, KE Han, TANG Xiaowu, CHEN Renpeng MOE Key Laboratory of Soft Soils and Geoenvironmental Engineering, Zhejiang University, Hangzhou 310027, China. 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2009年第4期552-560,共9页
The equivalence between multilayered barriers regarding diffusion and adsorption was studied. The bottom boundary of the liner system is defined by assuming concentration continuous and flux continuous conditions of t... The equivalence between multilayered barriers regarding diffusion and adsorption was studied. The bottom boundary of the liner system is defined by assuming concentration continuous and flux continuous conditions of the contaminant between the bottom liner layer and the underlying soil. Five different liner systems were compared in terms of solute breakthrough time. The results of the analysis showed that breakthrough time of the hydrophobic organic compounds for a 2-meter-thick compacted clay liner (CCL) could be 3-4 orders of magnitude is greater than the breakthrough time for a geosynthetic clay liner (GCL) composite liner. The GM/GCL and GM/CCL composite liner systems provide a better diffusion barrier for the hydrophilic organic compounds than that for the hydrophobic compounds due to their different Henry's coefficient. The calculated breakthrough times of the organic contaminants for the Chinese standard liner systems were found to be generally greater than those for the GCL alternatives, for the specific conditions examined. If the distribution coefficient increases to 2.8 for the hydrophobic compounds or 1.0 for the hydrophilic compounds, the thickness of the attenuation layer needed to achieve the same breakthrough time as the standard liner systems can be reduced by a factor of about 1.9-2.4. As far as diffusive and adsorption contaminant transport are concerned, GM or GCL is less effective than CCL. 展开更多
关键词 liner system equivalency organic contaminant LANDFILL DIFFUSION ADSORPTION
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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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Bedside index for severity in acute pancreatitis:comparison with other scoring systems in predicting severity and organ failure 被引量:37
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作者 Ji Young Park Tae Joo Jeon +5 位作者 Tae Hwan Ha Jin Tae Hwang Dong Hyun Sinn Tae-Hoon Oh Won Chang Shin Won-Choong 《Hepatobiliary & Pancreatic Diseases International》 SCIE CAS 2013年第6期645-650,共6页
BACKGROUND:The early identification of severe acute pancreatitis is important for the management and for improving outcomes.The bedside index for severity in acute pancreatitis(BISAP)has been considered as an accurate... BACKGROUND:The early identification of severe acute pancreatitis is important for the management and for improving outcomes.The bedside index for severity in acute pancreatitis(BISAP)has been considered as an accurate method for risk stratification in patients with acute pancreatitis.This study aimed to evaluate the comparative usefulness of the BISAP.METHODS:We retrospectively analyzed 303 patients with acute pancreatitis diagnosed at our hospital from March 2007to December 2010.BISAP,APACHE-II,Ranson criteria,and CT severity index(CTSI)of all patients were calculated.We stratified the number of patiants with severe pancreatitis,pancreatic necrosis,and organ failure as well as the number of deaths by BISAP score.We used the area under the receiveroperating curve(AUC)to compare BISAP with other scoring systems,C-reactive protein(CRP),hematocrit,and body mass index(BMI)with regard to prediction of severe acute pancreatitis,necrosis,organ failure,and death.RESULTS:Of the 303 patiants,31(10.2%)were classified as having severe acute pancreatitis.Organ failure occurred in 23(7.6%)patients,pancreatic necrosis in 40(13.2%),and death in6(2.0%).A BISAP score of 2 was a statistically significant cutoff value for the diagnosis of severe acute pancreatitis,organ failure,and mortality.AUCs for BISAP predicting severe pancreatitis and death were 0.80 and 0.86,respectively,which were similar to those for APACHE-II(0.80,0.87)and Ranson criteria(0.74,0.74)and greater than AUCs for CTSI(0.67,0.42).The AUC for organ failure predicted by BISAP,APACHE-II,Ranson criteria,and CTSI was 0.93,0.95,0.84 and 0.57,respectively.AUCs for BISAP predicting severity,organ failure,and death were greater than those for CRP(0.69,0.80,0.72),hematocrit(0.45,0.35,0.14),and BMI(0.41,0.47,0.17).CONCLUSION:The BISAP predicts severity,death,and especially organ failure in acute pancreatitis as well as APACHE-II does and better than Ranson criteria,CTSI,CRP,hematocrit,and BMI. 展开更多
关键词 acute pancreatitis scoring system pancreatic necrosis organ failure
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Method for designing organization decision support system framework 被引量:1
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作者 Fan Jiancong Liang Yongquan Zeng Qingtian 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2006年第4期764-768,共5页
The concept of organization decision support system (ODSS) is defined according to practical applications and novel understanding. And a framework for ODSS is designed. The framework has three components: infrastru... The concept of organization decision support system (ODSS) is defined according to practical applications and novel understanding. And a framework for ODSS is designed. The framework has three components: infrastructure, decision-making process and decision execution process. Infrastructure is responsible to transfer data and information. Decision-making process is the ODSS's soul to support decision-making. Decision execution process is to evaluate and execute decision results derived from decision-making process. The framework presents a kind of logic architecture. An example is given to verify and analyze the framework. The analysis shows that the framework has practical values, and has also reference values for understanding ODSS and for theoretical studies. 展开更多
关键词 terms-decision support system organization decision organization decision support system.
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Hierarchical Self-organization of Complex Systems 被引量:27
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作者 CHAILi-he WENDong-sheng 《Chemical Research in Chinese Universities》 SCIE CAS CSCD 2004年第4期440-445,共6页
Researches on organization and structure in complex systems are academic and industrial fronts in modern sciences. Though many theories are tentatively proposed to analyze complex systems, we still lack a rigorous the... Researches on organization and structure in complex systems are academic and industrial fronts in modern sciences. Though many theories are tentatively proposed to analyze complex systems, we still lack a rigorous theory on them. Complex systems possess various degrees of freedom, which means that they should exhibit all kinds of structures. However, complex systems often show similar patterns and structures. Then the question arises why such similar structures appear in all kinds of complex systems. The paper outlines a theory on freedom degree compression and the existence of hierarchical self-organization for all complex systems is found. It is freedom degree compression and hierarchical self-organization that are responsible for the existence of these similar patterns or structures observed in the complex systems. 展开更多
关键词 Complex systems Degrees of freedom HIERARCHICAL SELF-organIZATION
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Semantic Social Service Organization Mechanism in Cyber Physical System 被引量:1
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作者 张波 潘晓声 潘建国 《Transactions of Nanjing University of Aeronautics and Astronautics》 EI 2014年第4期452-462,共11页
Cyber physical system(CPS)provides more powerful service by cyber and physical features through the wireless communication.As a kind of social organized network system,a fundamental question of CPS is to achieve servi... Cyber physical system(CPS)provides more powerful service by cyber and physical features through the wireless communication.As a kind of social organized network system,a fundamental question of CPS is to achieve service self-organization with its nodes autonomously working in both physical and cyber environments.To solve the problem,the social nature of nodes in CPS is firstly addressed,and then a formal social semantic descriptions is presented for physical environment,node service and task in order to make the nodes communicate automatically and physical environment sensibly.Further,the Horn clause is introduced to represent the reasoning rules of service organizing.Based on the match function,which is defined for measurement between semantics,the semantic aware measurement is presented to evaluate whether environment around a node can satisfy the task requirement or not.Moreover,the service capacity evaluation method for nodes is addressed to find out the competent service from both cyber and physical features of nodes.According to aforementioned two measurements,the task semantic decomposition algorithm and the organizing matrix are defined and the service self-organizing mechanism for CPS is proposed.Finally,examinations are given to further verify the efficiency and feasibility of the proposed mechanism. 展开更多
关键词 cyber physical system(CPS) self-organizing mechanism SEMANTIC environment-aware measurement service capacity evaluation
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Characteristics of soil organic carbon and total nitrogen under various grassland types along a transect in a mountain-basin system in Xinjiang, China 被引量:5
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作者 BI Xu LI Bo +3 位作者 NAN Bo FAN Yao FU Qi ZHANG Xinshi 《Journal of Arid Land》 SCIE CSCD 2018年第4期612-627,共16页
Soil organic carbon (SOC) and soil total nitrogen (STN) in arid regions are important components of global C and the N cycles, and their response to climate change will have important implications for both ecosyst... Soil organic carbon (SOC) and soil total nitrogen (STN) in arid regions are important components of global C and the N cycles, and their response to climate change will have important implications for both ecosystem processes and global climate feedbacks. Grassland ecosystems of Funyun County in the southern foot of the Altay Mountains are characterized by complex topography, suggesting large variability in the spatial distribution of SOC and STN. However, there has been little investigation of SOC and STN on grasslands in arid regions with a mountain-basin structure. Therefore, we investigated the characteristics of SOC and STN in different grassland types in a mountain-basin system at the southern foot of the Altai Mountains, north of the Junggar Basin in China, and explored their potential influencing factors and relationships with meteorological factors and soil properties. We found that the concentrations and storages of SOC and STN varied significantly with grassland type, and showed a decreasing trend along a decreasing elevation gradient in alpine meadow, mountain meadow, temperate typical steppe, temperate steppe desert, and temperate steppe desert. In addition, the SOC and STN concentrations decreased with depth, except in the temperate desert steppe. According to Pearson's correlation values and redundancy analysis, the mean annual precipitation, soil moisture content and soil available N concentration were significantly positively correlated with the SOC and STN concentrations. In contrast, the mean annual temperature, pH, and soil bulk density were significantly and negatively correlated with the SOC and STN concentrations. The mean annual precipitation and mean annual temperature were the primary factors related to the SOC and STN concentrations. The distributions of the SOC and STN concentrations were highly regulated by the elevation-induced differences in meteorological factors. Mean annual precipitation and mean annual temperature together explained 97.85% and 98.38% of the overall variations in the SOC and STN concentrations, respectively, at soil depth of 0-40 cm, with precipitation making the greatest contribution. Our results provide a basis for estimating and predicting SOC and STN concentrations in grasslands in arid regions with a mountain-basin structure. 展开更多
关键词 mountain-basirl system grassland types soil organic carbon soil total nitrogen meteorological factors soil properties
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Distribution of Crystal Organic Fertilizer-N in Soil-plant System 被引量:8
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作者 LIU Yi-xin, HAN Yi-wang, WANG Yan-ting, HONG Li-fang XU Xi-min,TANG Shen, LIN Guan-ya and LIU Wu-ding(Department of Environmental Science , Institute of Earth and Space , University of Science and Technology of China , Hefei 230026 , P. R . China Department of Tobacco Science , University of Science and Technology of China , Hefei 230052 , P. R . China +5 位作者 Department of Science , Technology and Education of Tobacco Monopoly Administration of China , Beijing 100052 , P. R . China Institute of Soil and Fertilizer , Yunnan Academy of Agricultural science , Kunmin 650231 , P. R . China Sanmin Tobacco Branch Company of Fujians , Sanmin 365010 , P. R . China Yongzhou Tobacco Branch Company of Hunan , Yongzhou 425000 , P. R . China Sinan Tobacco Company of Guizhou , Sinan 565100 , P. R . China Department of Resources , Environment and Agrochemistry , Huazhong Agricultural University, Wuhan 430070 , P.R.China) 《Agricultural Sciences in China》 CAS CSCD 2002年第9期1012-1016,共5页
The distribution of crystal organic fertilizer, urea and compound fertilizer-N in soil and plant system was researched with 15N-trace under tobacco pot experiment. The results showed that the leaf yield of tobacco use... The distribution of crystal organic fertilizer, urea and compound fertilizer-N in soil and plant system was researched with 15N-trace under tobacco pot experiment. The results showed that the leaf yield of tobacco used crystal organic fertilizer was 23.1% and 14.6% higher than that of urea and compound fertilizer treatments respectively. Compound fertilizer also resulted in higher yield of 8.5 % comparing with the urea treatment. Nitrogen content of the plant from the crystal organic fertilizer treatment was 138. 6% and 145.7% as high as that of the compound fertilizer and urea treatments respectively. The absorbed N from the organic fertilizer was 25.1% and 27.9% more than that from the compound fertilizer and urea respectively. However, the absorbed N from the soil with the organic fertilizer was 47.4% and 58.3% more than that with compound fertilizer and urea respectively. The N use efficiency of the organic fertilizer was 9.4% and 10.1% higher than that of the compound fertilizer and urea. It indicated that the crystal organic fertilizer not only had high N use efficiency, but also stimulated tobacco taking up more N from soil. 展开更多
关键词 TOBACCO Crystal organic fertilizer-N Soil-plant system
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Clogging Process Caused by Organic Particle Accumulation and Biofilm Growth in Subsurface Wastewater Infiltration System
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作者 潘晶 于龙 王艳 《Journal of Donghua University(English Edition)》 EI CAS 2012年第2期187-192,共6页
Substrate clogging is the worst operational problem for subsurface wastewater infiltration system ( SWIS ), nevertheless quantitative understanding of the clogging process is currently very limited. In this study, t... Substrate clogging is the worst operational problem for subsurface wastewater infiltration system ( SWIS ), nevertheless quantitative understanding of the clogging process is currently very limited. In this study, the developing process of clogging caused by organic particle accumulation and biofilm growth was investigated in two groups of lab-scale SWIS, which were fed with glucose (dissolved organic matter) and starch (particulate organic matter) influent and filled with the same substrate made of 50% brown soil and cinder at a weight of 50%. Results showed that in glucose-fed systems the growth of biofilm in the substrate pores certainly caused remarkable reduction of effective porosity, especially for the high concentration organic wastewater, whereas its influence on infiltration rate was negligible. In comparison with biofllm growth, organic particles accumulation could rapidly reduce infiltration rate and the clogging occurred in the upper layer in starch-fed systems and the most important contribution of biofilm growth to clogging was accelerating the occurrence of clogging. 展开更多
关键词 subsutface wastewater infiltration system (SWIS) organic particle accumulation infiltration rate effective porosity
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PBL联合CBL教学法在实验诊断学住培教学中的应用 被引量:3
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作者 杜雪飞 薛丽 +4 位作者 梁红艳 柳俊年 潘靖 杨春 辛瑜 《中国继续医学教育》 2024年第8期36-39,共4页
目的研究以问题为基础的教学法(problem-based learning,PBL)联合案例教学法(case-based learning,CBL)在住院医师规范化培训(简称住培)医师实验诊断学以系统-器官疾病为中心的教学改革中的应用效果。方法选取2017年6月—2020年6月哈尔... 目的研究以问题为基础的教学法(problem-based learning,PBL)联合案例教学法(case-based learning,CBL)在住院医师规范化培训(简称住培)医师实验诊断学以系统-器官疾病为中心的教学改革中的应用效果。方法选取2017年6月—2020年6月哈尔滨医科大学附属第四医院检验科内设置的医学检验专业住培基地的住培医师60名为研究对象,随机选取2017~2018年度住培医师30名纳入对照组,采用普通五年制教材传统教学法。将2019~2020年度住培医师30名纳入观察组,采用PBL联合CBL教学法。比较2组住培医师考试成绩、学习效果及教学满意度。结果观察组的优良率为100%,高于对照组的80.00%,差异有统计学意义(P<0.05)。观察组住培医师学习主动性、思辨力、团队协作、有效沟通4个维度的得分均高于对照组,差异有统计学意义(P<0.05)。观察组住培医师的总满意度为100%,高于对照组的73.33%,差异有统计学意义(P<0.05)。结论PBL联合CBL教学法在住培医师实验诊断学以系统-器官疾病为中心的教学改革中的应用效果较好,提高了住培医师成绩,锻炼了住培医师解决临床问题的综合能力。 展开更多
关键词 PBL CBL 住培医师 系统-器官疾病 实验诊断学 教学改革
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Self-organization of Reconfigurable Protocol Stack for Networked Control Systems 被引量:1
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作者 Chun-Jie Zhou Hui Chen Yuan-Qing Qin Yu-Feng Shi Guang-Can Yu 《International Journal of Automation and computing》 EI 2011年第2期221-235,共15页
In networked control systems (NCS),the control performance depends on not only the control algorithm but also the communication protocol stack.The performance degradation introduced by the heterogeneous and dynamic ... In networked control systems (NCS),the control performance depends on not only the control algorithm but also the communication protocol stack.The performance degradation introduced by the heterogeneous and dynamic communication environment has intensified the need for the reconfigurable protocol stack.In this paper,a novel architecture for the reconfigurable protocol stack is proposed,which is a unified specification of the protocol components and service interfaces supporting both static and dynamic reconfiguration for existing industrial communication standards.Within the architecture,a triple-level self-organization structure is designed to manage the dynamic reconfiguration procedure based on information exchanges inside and outside the protocol stack.Especially,the protocol stack can be self-adaptive to various environment and system requirements through the reconfiguration of working mode,routing and scheduling table.Finally,the study on the protocol of dynamic address management is conducted for the system of controller area network (CAN).The results show the efficiency of our self-organizing architecture for the implementation of a reconfigurable protocol stack. 展开更多
关键词 Networked control system (NCS) communication network SELF-organIZATION protocol stack RECONFIGURATION
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The Evolution of Organic Carbon in Chinese Mollisol Under Different Farming Systems: Validation and Prediction by Using Century Model 被引量:6
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作者 GAO Chong-sheng WANG Jian-guo ZHANG Xing-yi SUI Yue-yu 《Agricultural Sciences in China》 CAS CSCD 2008年第12期1490-1496,共7页
Soil organic carbon (SOC) is an important indicator of soil degradation process. In this study, the long-term SOC evolution in Chinese mollisol farmland was simulated and predicted by validating, analyzing, processi... Soil organic carbon (SOC) is an important indicator of soil degradation process. In this study, the long-term SOC evolution in Chinese mollisol farmland was simulated and predicted by validating, analyzing, processing and assorting concerning data, based on clarifying parameters of Century model need, combined with best use of recorded data of field management, observed data of long-term experiments, climate, soil, and biology, and achieved results from Hailun Agro-Ecological Experimental Station, Chinese Academy of Sciences. The results were showed as follows: Before reclamation, SOC content was around 58.00 g kg^-1, SOC content dropped quickly in early years, and then decreased slowly after reclamation. SOC content was around 34.00 g kg^-1 with a yearly average rate of 8.91‰ decrease before long-term experiments was established. After a long-term experiment, SOC would change under different farming systems. Shift farming system changed as follows: By 20-year model simulation, SOC content decreased from 34.03 to 30.19 g kg^-1, with a yearly average rate of 5.97‰; by 100-year model simulation, SOC content decreased to 24.31 g kg^-1, with a yearly average rate of 3.36‰. Organic farming system changed as follows: By 20-year model simulation, SOC content decreased slowly from 34.03 to 33.39 g kg^-1, with a yearly average rate of 0.95‰, 5‰ less than that of shift farming system; by 100-year model simulation, SOC content decreased to 32.21 g kg^-1, with a yearly average rate of 0.55‰. "Petroleum" farming system changed as follows: By 20-year model simulation, SOC content decreased from 34.03 to 32.88 g kg^-1, with a yearly average rate of 1.72‰, much more than that of organic farming system; by 100-year model simulation, SOC content decreased to 30.89 g kg^-1, with a yearly average rate of 0.96‰. Combined "petroleum"-organic farming system changed as follows: By 20-year model simulation, SOC content was increased slightly; by 100-year model simulation, SOC content increased from 34.03 to 34.41g kg^-1, with a yearly average rate of 0.11‰. The above results provided an optimal way for maintaining SOC in Chinese mollisol farmland: To increase, as much as possible within agro-ecosystem, soil organic matter returns such as crop stubble, crop litter, crop straw or stalk, and manure, besides applying chemical nitrogen and phosphorous, which increased system productivity and maintained SOC content as well. Also, the results provided a valuable methodology both for a study of CO2 sequestration capacity and for a target fertility determination in Chinese mollisol. 展开更多
关键词 Century model Chinese mollisol farmland soil organic carbon various farming systems PREDICTION
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Power Generation Systems Using Continuous Blowdown Waste Heat from Drum Boilers Driving an Organic Rankine Cycle 被引量:2
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作者 LIU Qiang DUAN Yuanyuan WAN Xucai 《中国电机工程学报》 EI CSCD 北大核心 2013年第35期I0001-I0014,共14页
提出了一种利用汽包锅炉排污系统余热的有机朗肯循环发电系统,有机工质回收扩容器疏水的热量,并通过气轮机发电。建立了系统的热力性能分析模型,并对R227ea、RC318、R236ea、R245fa、R245ca、R123和R113等7种工质的热力性能进行了优化... 提出了一种利用汽包锅炉排污系统余热的有机朗肯循环发电系统,有机工质回收扩容器疏水的热量,并通过气轮机发电。建立了系统的热力性能分析模型,并对R227ea、RC318、R236ea、R245fa、R245ca、R123和R113等7种工质的热力性能进行了优化。结果表明,临界温度高的工质,其o2循环的最佳主气温度(蒸发温度)反而低;亚临界循环采用干流体时,过热不利于余热的利用;超临界循环可以改善热源与工质间的温度匹配,有利于增大系统输出功,但是其运行压力高、大比热区的传热恶化等问题是实际运行和设计需要考虑的因素;R236ea的热力性能优于其余6种工质。 展开更多
关键词 朗肯循环 余热驱动 连续排污 发电系统 锅炉 燃煤电厂 标准煤耗率 发电量
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Investigation of the immune effects of Scutellaria baicalensis on blood leukocytes and selected organs of the chicken's lymphatic system 被引量:4
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作者 Bozena Kroliczewska Stanislaw Graczyk +3 位作者 Jaroslaw Kroliczewski Aleksandra Pliszczak-Krol Dorota Mista Wojciech Zawadzki 《Journal of Animal Science and Biotechnology》 SCIE CAS CSCD 2017年第3期601-612,共12页
Background: The health of chickens and the welfare of poultry industry are central to the efforts of addressing global food security. Therefore, it is essential to study chicken immunology to maintain and improve its... Background: The health of chickens and the welfare of poultry industry are central to the efforts of addressing global food security. Therefore, it is essential to study chicken immunology to maintain and improve its health and to find novel and sustainable solutions. This paper presents a study on investigation of the effect of Scutellaria baicalensis root(SBR) on the immune response of broiler chicken, especially on lymphocytes and heterophils reactivity, regarding their contribution to the development of immunity of the chickens.Methods: The 121-day-old Hubbard Hi-Y male broiler hybrids were randomly assigned to four treatment groups,three SBR supplemented groups(0.5, 1.0, and 1.5% of SBR) and one control group. Each treatment was replicated five times with six birds per replicate pen in a battery brooder. Blood was collected after 3-(rd) and 6-(th)wk of the experiment, and hemoglobin and hematocrit values were determined, as well as total leukocyte count and differential count were performed. Nitroblue tetrazolium test and phagocytosis assay as nonspecific immune parameters and humoral immune responses to the antigenic challenge by sheep red blood cells were performed.Moreover, the ability of peripheral blood lymphocytes to form radial segmentation(RS) of their nuclei was analyzed.Body weight and relative weight of spleen, liver, and bursa of Fabricius were recorded.Results: Results showed that mean heterophile/lymphocyte ratio increased in the SBR groups compared to the control group and the blood of the chickens showed lymphocytic depletion. The results also demonstrated that the relative weight of bursa of Fabricius and spleen in groups fed with SBR significantly decreased compared to the control group. This study also showed that the addition of SBR significantly inhibited the formation of RS of nuclei compared to some cytotoxic substances.Conclusion: We found that SBR supplementation should be carefully evaluated when given to poultry. The excess intake of SBR supplementation may cause immunologic inhibition and may negatively affect the development of immune organs. SBR has inhibited the formation of radial segmentation nuclei showing antimetastatic properties and also the phagocytosis of chicken heterophils. 展开更多
关键词 Development of immune organs Leukocyte Lymphatic system Radial segmentation Scutellaria baicalensis Toxic effect
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