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A Sharding Scheme Based on Graph Partitioning Algorithm for Public Blockchain
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作者 Shujiang Xu Ziye Wang +4 位作者 Lianhai Wang Miodrag J.Mihaljevi′c Shuhui Zhang Wei Shao Qizheng Wang 《Computer Modeling in Engineering & Sciences》 SCIE EI 2024年第6期3311-3327,共17页
Blockchain technology,with its attributes of decentralization,immutability,and traceability,has emerged as a powerful catalyst for enhancing traditional industries in terms of optimizing business processes.However,tra... Blockchain technology,with its attributes of decentralization,immutability,and traceability,has emerged as a powerful catalyst for enhancing traditional industries in terms of optimizing business processes.However,transaction performance and scalability has become the main challenges hindering the widespread adoption of blockchain.Due to its inability to meet the demands of high-frequency trading,blockchain cannot be adopted in many scenarios.To improve the transaction capacity,researchers have proposed some on-chain scaling technologies,including lightning networks,directed acyclic graph technology,state channels,and shardingmechanisms,inwhich sharding emerges as a potential scaling technology.Nevertheless,excessive cross-shard transactions and uneven shard workloads prevent the sharding mechanism from achieving the expected aim.This paper proposes a graphbased sharding scheme for public blockchain to efficiently balance the transaction distribution.Bymitigating crossshard transactions and evening-out workloads among shards,the scheme reduces transaction confirmation latency and enhances the transaction capacity of the blockchain.Therefore,the scheme can achieve a high-frequency transaction as well as a better blockchain scalability.Experiments results show that the scheme effectively reduces the cross-shard transaction ratio to a range of 35%-56%and significantly decreases the transaction confirmation latency to 6 s in a blockchain with no more than 25 shards. 展开更多
关键词 Blockchain sharding graph partitioning algorithm
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Purification of Moringa oleifera Leaves Protease by Three-Phase Partitioning and Investigation of Its Potential Antibacterial Activity
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作者 Adam Abdoulaye Agossou D. P. Noumavo +6 位作者 Durand Dah-Nouvlessounon Messan A. B. Ohin Hasan Bayraktar Farid T. Bade Honoré S. Bankole Lamine Baba-Moussa Farid Baba-Moussa 《American Journal of Plant Sciences》 CAS 2023年第1期64-76,共13页
One of plant-based products for dental care is plant-based proteolytic enzymes which are principally proteases. In order not to damage the protein and bioactive content, an efficient method should be employed for thei... One of plant-based products for dental care is plant-based proteolytic enzymes which are principally proteases. In order not to damage the protein and bioactive content, an efficient method should be employed for their purifications. As such, three-phase partitioning (TPP) was used to purify protease from moringa (Moringa oleifera). TPP is an emerging, promising, non-chromatographic and economical technology which is simple, quick, efficient and often one-step process for the separation and purification of bioactive molecules from natural sources. It involves the addition of salt (ammonium sulphate) to the crude extract followed by the addition of an organic solvent (butanol). The protein appears as an interfacial precipitate between upper organic solvent and lower aqueous phases. The various conditions such as ammonium sulphate, ratio of crude extract to t-butanol and pH which are required for attaining efficient purification of the protease fractions were optimized. Under optimized conditions, it was seen that, 35% of ammonium sulphate saturation with 1:0.75 ratio of crude extract to t-butanol at pH 7 gave 4.94-fold purification with 96.20% activity yield of protease in the middle phase of the TPP system. The purified enzyme from Moringa oleifera has no antimicrobial effect on the pathogenic bacteria tested. However, this purified enzyme, can be considered as a promising agent, cheap, and safe source which is suitable for using in various industries. 展开更多
关键词 Three-Phase partitioning Moringa oleifera PROTEASE Protein Purification ANTIMICROBIAL
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Hybrid Graph Partitioning with OLB Approach in Distributed Transactions
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作者 Rajesh Bharati Vahida Attar 《Intelligent Automation & Soft Computing》 SCIE 2023年第7期763-775,共13页
Online Transaction Processing(OLTP)gets support from data partitioning to achieve better performance and scalability.The primary objective of database and application developers is to provide scalable and reliable dat... Online Transaction Processing(OLTP)gets support from data partitioning to achieve better performance and scalability.The primary objective of database and application developers is to provide scalable and reliable database systems.This research presents a novel method for data partitioning and load balancing for scalable transactions.Data is efficiently partitioned using the hybrid graph partitioning method.Optimized load balancing(OLB)approach is applied to calculate the weight factor,average workload,and partition efficiency.The presented approach is appropriate for various online data transaction applications.The quality of the proposed approach is examined using OLTP database benchmark.The performance of the proposed methodology significantly outperformed with respect to metrics like throughput,response time,and CPU utilization. 展开更多
关键词 Data–partitioning SCALABILITY OPTIMIZATION THROUGHPUT
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2D Minimum Compliance Topology Optimization Based on a Region Partitioning Strategy
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作者 Chong Wang Tongxing Zuo +3 位作者 Haitao Han Qianglong Wang Han Zhang Zhenyu Liu 《Computer Modeling in Engineering & Sciences》 SCIE EI 2023年第7期655-683,共29页
This paper presents an extended sequential element rejection and admission(SERA)topology optimizationmethod with a region partitioning strategy.Based on the partitioning of a design domain into solid regions and weak ... This paper presents an extended sequential element rejection and admission(SERA)topology optimizationmethod with a region partitioning strategy.Based on the partitioning of a design domain into solid regions and weak regions,the proposed optimizationmethod sequentially implements finite element analysis(FEA)in these regions.After standard FEA in the solid regions,the boundary displacement of the weak regions is constrained using the numerical solution of the solid regions as Dirichlet boundary conditions.This treatment can alleviate the negative effect of the material interpolation model of the topology optimization method in the weak regions,such as the condition number of the structural global stiffness matrix.For optimization,in which the forward problem requires nonlinear structural analysis,a linear solver can be applied in weak regions to avoid numerical singularities caused by the over-deformedmesh.To enhance the robustness of the proposedmethod,the nonmanifold point and island are identified and handled separately.The performance of the proposed method is verified by three 2D minimum compliance examples. 展开更多
关键词 Topology optimization region partition nonmanifold point matrix conditional number geometric nonlinearity
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Assessing Criteria Weights by the Symmetry Point of Criterion (Novel SPC Method)–Application in the Efficiency Evaluation of the Mineral Deposit Multi-Criteria Partitioning Algorithm
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作者 Zoran Gligoric Milos Gligoric +2 位作者 Igor Miljanovic Suzana Lutovac Aleksandar Milutinovic 《Computer Modeling in Engineering & Sciences》 SCIE EI 2023年第7期955-979,共25页
Information about the relative importance of each criterion or theweights of criteria can have a significant influence on the ultimate rank of alternatives.Accordingly,assessing the weights of criteria is a very impor... Information about the relative importance of each criterion or theweights of criteria can have a significant influence on the ultimate rank of alternatives.Accordingly,assessing the weights of criteria is a very important task in solving multi-criteria decision-making problems.Three methods are commonly used for assessing the weights of criteria:objective,subjective,and integrated methods.In this study,an objective approach is proposed to assess the weights of criteria,called SPCmethod(Symmetry Point of Criterion).This point enriches the criterion so that it is balanced and easy to implement in the process of the evaluation of its influence on decision-making.The SPC methodology is systematically presented and supported by detailed calculations related to an artificial example.To validate the developed method,we used our numerical example and calculated the weights of criteria by CRITIC,Entropy,Standard Deviation and MEREC methods.Comparative analysis between these methods and the SPC method reveals that the developedmethod is a very reliable objective way to determine the weights of criteria.Additionally,in this study,we proposed the application of SPCmethod to evaluate the efficiency of themulti-criteria partitioning algorithm.The main idea of the evaluation is based on the following fact:the greater the uniformity of the weights of criteria,the higher the efficiency of the partitioning algorithm.The research demonstrates that the SPC method can be applied to solving different multi-criteria problems. 展开更多
关键词 Multi-criteria decision-making weights of criteria symmetry point of criterion mineral deposit partitioning algorithm performance evaluation
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Effects of Spin Transition and Cation Substitution on the Optical Properties and Iron Partitioning in Carbonate Minerals
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作者 HU Jun XU Liangxu +1 位作者 LIU Jin YUE Donghui 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2023年第1期350-357,共8页
The high-pressure behavior of deep carbonate dictates the state and dynamics of oxidized carbon in the Earth's mantle,playing a vital role in the global carbon cycle and potentially influencing long-term climate c... The high-pressure behavior of deep carbonate dictates the state and dynamics of oxidized carbon in the Earth's mantle,playing a vital role in the global carbon cycle and potentially influencing long-term climate change.Optical absorption and Raman spectroscopic measurements were carried out on two natural carbonate samples in diamond-anvil cells up to 60 GPa.Mg-substitution in high-spin siderite FeCO_(3)increases the crystal field absorption band position by approximately 1000 cm^(-1),but such an effect is marginal at>40 GPa when entering the low-spin state.The crystal field absorption band of dolomite cannot be recognized upon compression to 45.8 GPa at room temperature but,in contrast,the high-pressure polymorph of dolomite exhibits a strong absorption band at frequencies higher than(Mg,Fe)CO_(3)in the lowspin state by 2000–2500 cm^(-1).Additionally,these carbonate minerals show more complicated features for the absorption edge,decreasing with pressure and undergoing a dramatic change through the spin crossover.The optical and vibrational properties of carbonate minerals are highly correlated with iron content and spin transition,indicating that iron is preferentially partitioned into low-spin carbonates.These results shed new light on how carbonate minerals evolve in the mantle,which is crucial to decode the deep carbon cycle. 展开更多
关键词 carbonate petrology/mineralogy MANTLE high pressure diamond-anvil cell iron spin transition iron partitioning deep carbon cycle
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Slope deformation partitioning and monitoring points optimization based on cluster analysis
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作者 LI Yuan-zheng SHEN Jun-hui +3 位作者 ZHANG Wei-xin ZHANG Kai-qiang PENG Zhang-hai HUANG Meng 《Journal of Mountain Science》 SCIE CSCD 2023年第8期2405-2421,共17页
The scientific and fair positioning of monitoring locations for surface displacement on slopes is a prerequisite for early warning and forecasting.However,there is no specific provision on how to effectively determine... The scientific and fair positioning of monitoring locations for surface displacement on slopes is a prerequisite for early warning and forecasting.However,there is no specific provision on how to effectively determine the number and location of monitoring points according to the actual deformation characteristics of the slope.There are still some defects in the layout of monitoring points.To this end,based on displacement data series and spatial location information of surface displacement monitoring points,by combining displacement series correlation and spatial distance influence factors,a spatial deformation correlation calculation model of slope based on clustering analysis was proposed to calculate the correlation between different monitoring points,based on which the deformation area of the slope was divided.The redundant monitoring points in each partition were eliminated based on the partition's outcome,and the overall optimal arrangement of slope monitoring points was then achieved.This method scientifically addresses the issues of slope deformation zoning and data gathering overlap.It not only eliminates human subjectivity from slope deformation zoning but also increases the efficiency and accuracy of slope monitoring.In order to verify the effectiveness of the method,a sand-mudstone interbedded CounterTilt excavation slope in the Chongqing city of China was used as the research object.Twenty-four monitoring points deployed on this slope were monitored for surface displacement for 13 months.The spatial location of the monitoring points was discussed.The results show that the proposed method of slope deformation zoning and the optimized placement of monitoring points are feasible. 展开更多
关键词 Excavation slope Surface displacement monitoring Spatial deformation analysis Clustering analysis Slope deformation partitioning Monitoring point optimization
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Fast Determination of Benzodiazepines in Human Urine via Liquid-Liquid Extraction with Low Temperature Partitioning and LC-HRMS 被引量:3
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作者 Elisangela Jaqueline Magalhaes Clesia Cristina Nascentes +3 位作者 Rodinei Augusti Maria Eliana Lopes Ribeiro de Queiroz Julio Cesar Cardoso da Silva Robson Jose de Cassia Franco Afonso 《American Journal of Analytical Chemistry》 2012年第2期118-124,共7页
A simple and high-throughput method to simultaneously determine selected benzodiazepines (i.e., diazepam, lorazepam, clonazepam, and bromazepam) in urine was developed and validated. The entire methodology consisted o... A simple and high-throughput method to simultaneously determine selected benzodiazepines (i.e., diazepam, lorazepam, clonazepam, and bromazepam) in urine was developed and validated. The entire methodology consisted of the application of an innovative extraction/cleanup procedure, namely liquid-liquid extraction with low-temperature partitioning (LLE-LTP), and analysis by liquid chromatography combined with high-resolution mass spectrometry (LC-HRMS). The LLE-LTP procedure was optimized via factorial design and by evaluating crucial variables, specifically the freezing mode (either slow or fast), the urine/acetonitrile volume ratio, and the sample ionic strength. The benzodiazepines were quantified using matrix-matched calibration curves where the following parameters were assessed by validation protocol: in general, linearity range of 17 - 200 μg?L–1 (r > 0.9957);limits of detection lower than 5 μg?L–1;relative standard deviations (RSD) lower than 12.5%;and accuracy ranging from 72.3 to 117%. To test this procedure’s performance, the method was applied to determine the content of diazepam in actual urine samples. The validation results obtained for the method demonstrated that the present methodology could be potentially applied in proficient laboratories as a routine approach for determining benzodiazepines compounds content in urine. 展开更多
关键词 BENZODIAZEPINES URINE LC-HRMS Extraction Procedure Low-Temperature partitioning
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Upper-rim-modified thioether thiacalix[4]arene used for liquid-liquid extraction of Au(Ⅲ)and Pd(Ⅱ)in hydrochloric acid medium
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作者 Sheng Wan Rong Xie +1 位作者 Jianhong Fan Kewen Tang 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2024年第2期110-118,共9页
Gold(Au)and palladium(Pd)play an increasing role in the production and human life;Therefore,it is of great significance to study their recovery.A 5,11,17,23-tetra-ethylthio-25,26,27,28-tetra-hydroxyl thiacalix[4]arene... Gold(Au)and palladium(Pd)play an increasing role in the production and human life;Therefore,it is of great significance to study their recovery.A 5,11,17,23-tetra-ethylthio-25,26,27,28-tetra-hydroxyl thiacalix[4]arene(TCAET)was synthesized specifically for the capture of Au(Ⅲ)and Pd(Ⅱ)from HCl medium by liquid-liquid extraction.In a 0.1 mol·L^(-1)HCl medium,the transfer of Au(Ⅲ)and Pd(Ⅱ)from the aqueous phase to the organic phase was highly efficient,with a transfer ratio of 100%for Au(Ⅲ)and 98%for Pd(Ⅱ).Furthermore,the extraction equilibrium time for Au(Ⅲ)was just 5 min.Job's method data demonstrated that TCAET formed complexes with Au(Ⅲ)and Pd(Ⅱ)in a ratio of 2:3 and 1:1,respectively,during the extraction process.TCAET showed high selectivity toward Pd(Ⅱ)and Au(Ⅲ)over other competing metal ions.Moreover,both Au(Ⅲ)and Pd(Ⅱ)could be successfully stripped from the loaded organic phases with a 1.0 mol·L^(-1)thiourea in 0.5 mol·L^(-1)HCl and 0.5 mol·L^(-1)thiourea in 0.5 mol·L^(-1)HCl,respectively.Results obtained from five consecutive extraction-stripping cycles showed good reusability of TCAET toward Au(Ⅲ)and Pd(Ⅱ)recovery.The conclusion can provide a certain reference for thiacalixarene in the recovery of precious metal species. 展开更多
关键词 arene Upper-rim modification liquid-liquid extraction Precious metal THIOETHER
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Hybrid Strategy of Partitioned and Monolithic Methods for Solving Strongly Coupled Analysis of Inverse and Direct Piezoelectric and Circuit Coupling
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作者 Daisuke Ishihara Syunnosuke Nozaki +1 位作者 Tomoya Niho Naoto Takayama 《Computer Modeling in Engineering & Sciences》 SCIE EI 2024年第8期1371-1386,共16页
The inverse and direct piezoelectric and circuit coupling are widely observed in advanced electro-mechanical systems such as piezoelectric energy harvesters.Existing strongly coupled analysis methods based on direct n... The inverse and direct piezoelectric and circuit coupling are widely observed in advanced electro-mechanical systems such as piezoelectric energy harvesters.Existing strongly coupled analysis methods based on direct numerical modeling for this phenomenon can be classified into partitioned or monolithic formulations.Each formulation has its advantages and disadvantages,and the choice depends on the characteristics of each coupled problem.This study proposes a new option:a coupled analysis strategy that combines the best features of the existing formulations,namely,the hybrid partitioned-monolithic method.The analysis of inverse piezoelectricity and the monolithic analysis of direct piezoelectric and circuit interaction are strongly coupled using a partitioned iterative hierarchical algorithm.In a typical benchmark problem of a piezoelectric energy harvester,this research compares the results from the proposed method to those from the conventional strongly coupled partitioned iterative method,discussing the accuracy,stability,and computational cost.The proposed hybrid concept is effective for coupled multi-physics problems,including various coupling conditions. 展开更多
关键词 Structure-piezoelectric-circuit interaction energy harvesting partitioned method monolithic method hybrid method
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Algorithm Selection Method Based on Coupling Strength for Partitioned Analysis of Structure-Piezoelectric-Circuit Coupling
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作者 Daisuke Ishihara Naoto Takayama 《Computer Modeling in Engineering & Sciences》 SCIE EI 2024年第2期1237-1258,共22页
In this study, we propose an algorithm selection method based on coupling strength for the partitioned analysis ofstructure-piezoelectric-circuit coupling, which includes two types of coupling or inverse and direct pi... In this study, we propose an algorithm selection method based on coupling strength for the partitioned analysis ofstructure-piezoelectric-circuit coupling, which includes two types of coupling or inverse and direct piezoelectriccoupling and direct piezoelectric and circuit coupling. In the proposed method, implicit and explicit formulationsare used for strong and weak coupling, respectively. Three feasible partitioned algorithms are generated, namely(1) a strongly coupled algorithm that uses a fully implicit formulation for both types of coupling, (2) a weaklycoupled algorithm that uses a fully explicit formulation for both types of coupling, and (3) a partially stronglycoupled and partially weakly coupled algorithm that uses an implicit formulation and an explicit formulation forthe two types of coupling, respectively.Numerical examples using a piezoelectric energy harvester,which is a typicalstructure-piezoelectric-circuit coupling problem, demonstrate that the proposed method selects the most costeffectivealgorithm. 展开更多
关键词 MULTIPHYSICS coupling strength partitioned algorithm structure-piezoelectric-circuit coupling strongly coupled algorithm weakly coupled algorithm
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Airgap-harmonic-oriented Partitioned Design Method of PMV Motor with Improved Torque Performances
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作者 Zhaopeng Wu Li Quan +3 位作者 Zixuan Xiang Deyang Fan Tengguang Wang Xiaoyong Zhu 《CES Transactions on Electrical Machines and Systems》 EI CSCD 2024年第1期43-50,共8页
Here,we introduce a partitioned design method that is oriented toward airgap harmonic for permanent magnet vernier(PMV)motors.The method proposes the utilization of airgap flux harmonics as an effective bridge between... Here,we introduce a partitioned design method that is oriented toward airgap harmonic for permanent magnet vernier(PMV)motors.The method proposes the utilization of airgap flux harmonics as an effective bridge between the torque design region and the torque performances.To illustrate the efficacy of this method,a partitioned design PMV motor is presented and compared with the initial design.Firstly,the torque design region of the rotor is artfully divided into the torque enhancement region and ripple reduction region.Meanwhile,the main harmonics that generate output torque are chosen and enhanced,optimization.Moreover,the harmonics that generate torque ripple are selected and reduced based on torque harmonics optimization.Finally,the functions of the partitioned PMV motor torque are assessed based on the finite element method.By the purposeful design of these two regions,the output torque is strengthened while torque ripple is inhibited effectively,verifying the effectiveness and reasonability of the proposed design method. 展开更多
关键词 Permanent magnet vernier(PMV)motor Airgap flux harmonic partitioned design Low torque ripple
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在随机损失数据情况下回归函数的Partitioning估计的强相合性
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作者 沙秋英 《黑龙江大学自然科学学报》 CAS 1996年第1期10-15,共6页
本文在不完全数据的情况下采用L1模得到了回归函数的Partitioning估计的强相合性.我们的结果只要求回归函数的P(P>1)阶矩有限,对回归函数没加任何光滑条件,并且我们的结果对任何分布都成立.
关键词 强相合 回归函数 随机损失数据 P估计
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Existing State and Partitioning of Rare Earth on Weathered Ores 被引量:44
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作者 池汝安 田君 +5 位作者 李中军 彭翠 吴元欣 李世荣 王存文 周志昂 《Journal of Rare Earths》 SCIE EI CAS CSCD 2005年第6期756-759,共4页
The existing state and partitioning of rare earth (RE) on weathered ores in Longnan County(LN), Xingfeng County(XF) and Ninghua County(NH) were characterized systematically by standard geological analytical me... The existing state and partitioning of rare earth (RE) on weathered ores in Longnan County(LN), Xingfeng County(XF) and Ninghua County(NH) were characterized systematically by standard geological analytical methods. It is found that RE in the weathered rare earth ores exist as four phases: (a) water soluble, (b) ion-exchangeable, (c) colloidal sediment (oxides), (d) minerals, in which mainly as ion exchangeable phase, accounting for nearly 80% of total RE, with about 20% in the form of colloid sediment phase and mineral phase, but very little as aqueous soluble phase. These rare earth partitioning were mainly chosen mid-heavy RE elements, occupying above 60%, but not equal in the four phases. The mid-heavy RE elements were primarily enriched in the ion exchangeable phase up to 40%, while the containment of cerium dioxide is below 2 %. The cerium deficiency occurs in the ion exchangeable phase in weathered ore. It results from that the Ce^3+ is oxidized into Ce^4+ and changes into CeO2. For LN ore, the containment of Y is high in weathered ore because Y-minerals are abundant in original rock. 展开更多
关键词 weathered existing state partitioning rare earths
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Investigation of heavy metal partitioning influenced by flue gas moisture and chlorine content during waste incineration 被引量:24
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作者 Qinghai Li,Aihong Meng,Jinyan Jia,Yanguo Zhang Department of Thermal Engineering,Key Laboratory for Thermal Science and Power Engineering of the Ministry of Education of China,Tsinghua University,Beijing 100084,China. 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2010年第5期760-768,共9页
The impact of moisture on the partitioning of the heavy metals including Pb,Zn,Cu and Cd in municipal solid waste (MSW) was studied in a laboratory tubular furnace.A thermodynamic investigation using CHEMKIN softwar... The impact of moisture on the partitioning of the heavy metals including Pb,Zn,Cu and Cd in municipal solid waste (MSW) was studied in a laboratory tubular furnace.A thermodynamic investigation using CHEMKIN software was performed to compare the experimental results.Simulated waste,representative of typical MSW with and without chlorine compounds,was burned at the background temperature of 700 and 950°C,respectively.In the absence of chlorine,the moisture content has no evident effect on the volatility of Pb,Zn and Cu at either 700 or 950°C,however,as flue gas moisture increasing the Cd distribution in the bottom ash increased at 700°C and reduced at 950°C,respectively.In the presence of chlorine,the flue gas moisture reduced the volatility of Pb,Zn and Cu due to the transformation of the more volatile metal chlorides into less volatile metal oxides,and the reduction became significant as chlorine content increase.For Cd,the chlorine promotes its volatility through the formation of more volatile CdCl 2.As a result,the increased moisture content increases the Pb,Zn,Cu and Cd concentrations in the bottom ash,which limits the utilization of the bottom ash as a construction material.Therefore,in order to accumulate heavy metals into the fly ash,MSW should be dried before incineration. 展开更多
关键词 heavy metals partitioning MOISTURE CHLORINE municipal solid waste incineration
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Effects of culm carbohydrate partitioning on basal stem strength in a high-yielding rice population 被引量:13
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作者 Jun Zhang Ganghua Li +7 位作者 Qingyu Huang Zhenghui Liu Chengqiang Ding She Tang Lin Chen Shaohua Wang Yanfeng Ding Weijian Zhang 《The Crop Journal》 SCIE CAS CSCD 2017年第6期478-487,共10页
Rice culm carbohydrate transport can simultaneously affect grain filling and stem lodging resistance by regulating non-structural carbohydrate(NSC) and structural carbohydrate(SC) contents. However, the relationship b... Rice culm carbohydrate transport can simultaneously affect grain filling and stem lodging resistance by regulating non-structural carbohydrate(NSC) and structural carbohydrate(SC) contents. However, the relationship between carbohydrate transposition and culm strength is not well documented. Accordingly, a high-yielding hybrid rice cultivar(Y Liangyou 2) was tested under different N fertilization regimes at two locations, Taoyuan(a special high-yield eco-site), Yunnan province and Danyang(a representative eco-site of the middle and lower Yangtze), Jiangsu province, China. Significantly higher grain yield and basal stem strength were found at Taoyuan than Danyang under all N rates throughout the two-year experiment. At heading stage, soluble sugars, starch, cellulose and lignin contents of the basal culm at Taoyuan were significantly 132.0%, 73.7%, 1.2%, and 62.7% higher than those at Danyang, respectively. At 20 days after heading, soluble sugars and starch content at Taoyuan decreased significantly compared to Danyang, but lignin content remained higher. Culm carbohydrate transport to kernels at Taoyuan was significantly greater than that at Danyang, and the proportion of soluble sugars and starch was correspondingly 62.9%lower. However, the proportion of lignin and cellulose was 22.7% higher at Taoyuan than that at Danyang. Soluble sugars and starch partitioning were significantly reduced under an increased nitrogen application rate, but SC partitioning was little affected. There were significant positive correlations between basal culm bending stress and dry weight and cellulose and lignin proportions at both locations under all N rates, suggesting that the higher SC proportion at 20 days after heading was primarily responsible for culm strength.These results suggest that high-yielding rice populations with greater culm strength require both moderate NSC transport and greater SC accumulation. 展开更多
关键词 RICE HIGH-YIELDING LODGING CULM strength CARBOHYDRATE partitioning
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Late Quaternary Slip-rates and Slip Partitioning on the Southeastern Xianshuihe Fault System, Eastern Tibetan Plateau 被引量:18
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作者 CHEN Guihua XU Xiwei +1 位作者 WEN Xueze CHEN Yue-Gau 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2016年第2期537-554,共18页
Quantitative analysis of the kinematics of the active faults distributed around the QinghaiTibetan Plateau is critical to understand current tectonic processes of the plateau. Chronological analysis, based on the comp... Quantitative analysis of the kinematics of the active faults distributed around the QinghaiTibetan Plateau is critical to understand current tectonic processes of the plateau. Chronological analysis, based on the comparison among regional climate and geomorphology, digital photogrammetry, offset landforms, and the tectonics were adopted in this study on the Xianshuihe fault in the eastern Tibetan plateau. Two or more offset-age data were obtained for each segment of the Xianshuihe and theYunongxi faults. The offset landforms, including river terrace, alluvial fan and glacial moraine, provide constraints for the late Quaternary slip rate of the Xianshuihe fault. The left-lateral strike slip rate of the Xianshuihe fault decreases from 17 mm/a on the northwest segment to 9.3 mm/a on the southeast segment. Regarding the Xianshuihe fault zone and its adjacent blocks as a regional tectonic system, vector analysis was used to quantitatively analyze the longitudinal kinematical transformation and transversal slip partitioning on the fault zone in terms of the kinematical parameters of the main faults within the zone. The results show that there is a distributed vertical uplift at a rate of 6.1 mm/yr caused by shortening across the Gongga Mountains region. Based on these results, we established a model of the slip partitioning for the southeastern segment of the Xianshuihe fault zone. 展开更多
关键词 slip partitioning kinematical transformation tectonic morphology Xianshuihe fault Gongga Mountains
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Influence of High Temperature Stress on Net Photosynthesis, Dry Matter Partitioning and Rice Grain Yield at Flowering and Grain Filling Stages 被引量:19
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作者 L Guo-hua WU Yong-feng +3 位作者 BAI Wen-bo MA Bao WANG Chun-yan SONG Ji-qing 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2013年第4期603-609,共7页
Climate change is recognized to increase the frequency and severity of extreme temperature events. At flowering and grain filling stages, risk of high temperature stress (HTS) on rice might increase, and lead to dec... Climate change is recognized to increase the frequency and severity of extreme temperature events. At flowering and grain filling stages, risk of high temperature stress (HTS) on rice might increase, and lead to declining grain yields. A regulated cabinet experiment was carried out to investigate effects of high temperature stress on rice growth at flowering and grain- filling stages. Results showed that no obvious decrease pattern in net photosynthesis appeared along with the temperature rising, but the dry matter allocation in leaf, leaf sheath, culm, and panicle all changed. Dry weight of panicle decreased, and ratio of straw to total above ground crop dry weight increased 6-34% from CK, which might have great effects on carbon cycling and green house gas emission. Grain yield decreased significantly across all treatments on average from 15 to 73%. Occurrence of HTS at flowering stage showed more serious influence on grain yield than at grain filling stage. High temperature stress showed negative effects on harvest index. It might be helpful to provide valuable information for crop simulation models to capture the effects of high temperature stress on rice, and evaluate the high temperature risk. 展开更多
关键词 dry matter partitioning grain yield high temperature stress rice growth
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Interface Migration between Martensite and Austenite during Quenching and Partitioning (Q&P) Process 被引量:19
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作者 Ning ZHONG Xiaodong WANG +1 位作者 Yonghua RONG Li WANG 《Journal of Materials Science & Technology》 SCIE EI CAS CSCD 2006年第6期751-754,共4页
An Fe-0.2C-1.5Si-1.67Mn steel was subjected to quenching and partitioning (Q&P) process, and the interface migration between martensite and austenite at an elevated partitioning temperature was observed. The interf... An Fe-0.2C-1.5Si-1.67Mn steel was subjected to quenching and partitioning (Q&P) process, and the interface migration between martensite and austenite at an elevated partitioning temperature was observed. The interface migration is excluded in constrained paraequilibrium (CPE) model. Based on "endpoint" predicted by CPE model the thermodynamic condition of interface migration is analyzed, that is, the difference in the chemical potential of iron in both ferrite (martenisite) and austenite produces the driving force of the iron atoms to migrate from one phase to the other phase. In addition, the interface migration can change the austenite fraction; as a result, the austenite fraction at partitioning temperature may be higher than that at quenching temperature through the interface migration, but this phenomenon cannot be explained by CPE model. 展开更多
关键词 Quenching and partitioning (Q&P) Constrained paraequilibrium (CPE) MARTENSITE AUSTENITE Interface migration
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Distribution and partitioning of heavy metals in large anthropogenically impacted river, the Pearl River, China 被引量:5
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作者 Silan Liu Zhongwei Wang +7 位作者 Yuanyuan Zhang Yulong Liu Wei Yuan Ting Zhang Yujie Liu Ping Li Li He Jiubin Chen 《Acta Geochimica》 EI CAS CSCD 2019年第2期216-231,共16页
In order to evaluate the distribution and partitioning characteristics of heavy metals in the large anthropogenically impacted Pearl River Basin, the contents of ‘‘anthropophile'' elements(Cr, Ni, Cu, Zn, Cd... In order to evaluate the distribution and partitioning characteristics of heavy metals in the large anthropogenically impacted Pearl River Basin, the contents of ‘‘anthropophile'' elements(Cr, Ni, Cu, Zn, Cd and Pb,which are clearly influenced by human activities) were determined, and their partitioning coefficients(Kd) between water and sediments and enrichment factors(EF) were calculated for samples collected at different locations along the Pearl River main stream. The modified BCR sequential extraction procedure(proposed by the European Community Bureau of Reference in 1993), which involves the successive extraction of metals in a decreasing order of reactivity, was applied. Sediment samples from the upper,middle, and lower reaches were included in this study. The results showed that the content of most metals in water and sediment samples gradually increases from upstream to downstream, suggesting a possible input from human activities as shown by their increasing high EF, ranged from 1.4 to 3.9 for Cu, from 1.4 to 6.7 for Zn, from 2.5 to59.1 for Cd, and from 1.7 to 8.9 for Pb, respectively. Thehigher partition coefficients(Kd) for Cr, Zn, and Pb(10~5–10~6) indicated that they were mainly transported in solid phase, while parts of Ni, Cu, and Cd were transported in dissolved phase as they display relatively lower Kdin the range of 10~4–10~5. According to the results of the BCR leaching, the percentage of non-residual fraction of heavy metals in the sediments showed a decreasing order of Cd [ Pb [ Zn [ Cu [ Ni [ Cr, implying that Cd and Pb were more active and bioavailable compared to the other four metals, and thus would be potentially more harmful to the watershed ecosystem. 展开更多
关键词 PEARL RIVER Water and SEDIMENT HEAVY metals partitioning DISTRIBUTION
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