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Improved methods,properties,applications and prospects of microbial induced carbonate precipitation(MICP)treated soil:A review 被引量:2
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作者 Xuanshuo Zhang Hongyu Wang +3 位作者 Ya Wang Jinghui Wang Jing Cao Gang Zhang 《Biogeotechnics》 2025年第1期34-54,共21页
Soil improvement is one of the most important issues in geotechnical engineering practice.The wide application of traditional improvement techniques(cement/chemical materials)are limited due to damage ecological en-vi... Soil improvement is one of the most important issues in geotechnical engineering practice.The wide application of traditional improvement techniques(cement/chemical materials)are limited due to damage ecological en-vironment and intensify carbon emissions.However,the use of microbially induced calcium carbonate pre-cipitation(MICP)to obtain bio-cement is a novel technique with the potential to induce soil stability,providing a low-carbon,environment-friendly,and sustainable integrated solution for some geotechnical engineering pro-blems in the environment.This paper presents a comprehensive review of the latest progress in soil improvement based on the MICP strategy.It systematically summarizes and overviews the mineralization mechanism,influ-encing factors,improved methods,engineering characteristics,and current field application status of the MICP.Additionally,it also explores the limitations and correspondingly proposes prospective applications via the MICP approach for soil improvement.This review indicates that the utilization of different environmental calcium-based wastes in MICP and combination of materials and MICP are conducive to meeting engineering and market demand.Furthermore,we recommend and encourage global collaborative study and practice with a view to commercializing MICP technique in the future.The current review purports to provide insights for engineers and interdisciplinary researchers,and guidance for future engineering applications. 展开更多
关键词 Soil improvement Bio-cement MICP improved methods Field application cases
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Topology Optimization of Orthotropic Materials Using the Improved Element-Free Galerkin (IEFG) Method
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作者 Wenna He Yichen Yang +1 位作者 Dongqiong Liang Heng Cheng 《Computers, Materials & Continua》 2025年第4期1415-1437,共23页
In this paper,we develop an advanced computational framework for the topology optimization of orthotropic materials using meshless methods.The approximation function is established based on the improved moving least s... In this paper,we develop an advanced computational framework for the topology optimization of orthotropic materials using meshless methods.The approximation function is established based on the improved moving least squares(IMLS)method,which enhances the efficiency and stability of the numerical solution.The numerical solution formulas are derived using the improved element-free Galerkin(IEFG)method.We introduce the solid isotropic microstructures with penalization(SIMP)model to formulate a mathematical model for topology opti-mization,which effectively penalizes intermediate densities.The optimization problem is defined with the numerical solution formula and volume fraction as constraints.The objective function,which is the minimum value of flexibility,is optimized iteratively using the optimization criterion method to update the design variables efficiently and converge to an optimal solution.Sensitivity analysis is performed using the adjoint method,which provides accurate and efficient gradient information for the optimization algorithm.We validate the proposed framework through a series of numerical examples,including clamped beam,cantilever beam,and simply supported beam made of orthotropic materials.The convergence of the objective function is demonstrated by increasing the number of iterations.Additionally,the stability of the iterative process is analyzed by examining the fluctuation law of the volume fraction.By adjusting the parameters to an appropriate range,we achieve the final optimization results of the IEFG method without the checkerboard phenomenon.Comparative studies between the Element-Free Galerkin(EFG)and IEFG methods reveal that both methods yield consistent optimization results under identical parameter settings.However,the IEFG method significantly reduces computational time,highlighting its efficiency and suitability for orthotropic materials. 展开更多
关键词 Solid isotropic microstructures with penalization method variable density method sensitivity analysis improved element-free Galerkin method meshless method
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Performance evaluation of sponge city PPP projects using improved matter-element extension method
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作者 CHEN Zhi-ding HU Min-qian 《Ecological Economy》 2025年第2期151-168,共18页
Sponge city(SPC)is proposed to solve the issues such as the degradation of urban water ecosystem environment,imbalanced water resource allocation,urban water logging,and water contamination.The PPP(Public Private Part... Sponge city(SPC)is proposed to solve the issues such as the degradation of urban water ecosystem environment,imbalanced water resource allocation,urban water logging,and water contamination.The PPP(Public Private Partnership)model is combined to release the government pressure of SPC project construction.The development of the SPC-PPP model makes significant contributions to the sustainable development and the enhancement of urban resilience against water-related disasters.However,there is no scientific performance evaluation system on its operation period has been conducted.Therefore,the SPC-PPP Evaluation model aims to objectively and reasonably assess project effectiveness,promote its development and refine the evaluation framework.This paper has set up the MEE model for performance evaluation,with improved Matter-Element Extension method to assign values to the evaluation indices.The research results show that:(1)The MEE model is more accurate in the performance evaluation and its effectiveness is reflected in its ability to capture the correlation among different indices in the same membership,rather than merely focusing on individual indices.(2)The proposed approach provided a new aspect for performance evaluation,improving the accuracy of evaluation and promoting the development of SPC-PPP project. 展开更多
关键词 public private partnership sponge city performance evaluation improved matter-element extension method
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Stability evaluation of the tunnel portal slope based on improved unascertained measure method
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作者 ZHANG Cengceng HUANG Shibing +1 位作者 ZHENG Luobin LI Wen 《Journal of Mountain Science》 2025年第6期2261-2275,共15页
The stability of the tunnel portal slope is crucial for ensuring safe tunnel construction.Thus,a sound stability evaluation is of significance.Given the unique geological characteristics of tunnel portal slopes,it is ... The stability of the tunnel portal slope is crucial for ensuring safe tunnel construction.Thus,a sound stability evaluation is of significance.Given the unique geological characteristics of tunnel portal slopes,it is necessary to establish a specific evaluation indicator system that differs from those used for ordinary slopes.Based on the unascertained measure method,uncertainties in the indicator are addressed by introducing the left and right half cloud asymmetric cloud model to optimize the linear membership function.The subjectivity of confidence criterion level identification is also improved by using the Euclidean distance method.Thus,a stability evaluation model for the tunnel portal slope is established based on the improved unascertained measure method.Finally,using the collected tunnel portal slope data,the results of four evaluation methods are compared with the safety factor levels.The evaluation methods include the traditional unascertained measure method,the method improved by using the left and right half cloud asymmetric cloud model,the method improved by using the Euclidean distance method,and the method improved by using both the left and right half cloud asymmetric cloud model and the Euclidean distance method.The results show that the accuracy rates of these four methods are 50%,55%,85%,and 90%,respectively.Among them,the joint improvement method has the slightest deviation,with only one level,while the other three methods had deviations of two levels.This result verifies the stability and effectiveness of the joint improvement method,providing a reference for tunnel portal slope stability evaluation. 展开更多
关键词 Tunnel portal slope Stability evaluation improved unascertained measure method Left and right half cloud asymmetric cloud model Euclidean distance method
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Advances in Research of Characteristics, Environmental Impact and Treatment Methods of Dairy Wastewater
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作者 Jiping XIE Ming QIAO +1 位作者 Ying BAI Li SONG 《Asian Agricultural Research》 2025年第3期18-21,39,共5页
Dairy wastewater,a kind of high concentration organic wastewater,is produced in large quantities and difficult to treat,and has a negative impact on the ecological environment.In this study,the source,composition,wate... Dairy wastewater,a kind of high concentration organic wastewater,is produced in large quantities and difficult to treat,and has a negative impact on the ecological environment.In this study,the source,composition,water quality characteristics of dairy wastewater and its impact on the ecological environment were analyzed,and the treatment methods of dairy wastewater at home and abroad in recent years were summarized,in order to provide a reference for the treatment of dairy wastewater. 展开更多
关键词 Dairy products WASTEWATER Treatment methods advances in research
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Novel multimodal analgesic regimen for perioperative pain management after hepatic artery infusion chemotherapy in patients with advanced hepatocellular carcinoma
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作者 Jing Yan Rui An +4 位作者 Jing-Jing Wang Min Wang Qi Zhao Shen Zhao Jian Xu 《World Journal of Gastrointestinal Surgery》 2025年第4期271-282,共12页
BACKGROUND Hepatic artery infusion chemotherapy(HAIC)is a widely used local therapeutic approach for intermediate to advanced-stage hepatocellular carcinoma(HCC),exhibiting considerable efficacy.However,the prevalence... BACKGROUND Hepatic artery infusion chemotherapy(HAIC)is a widely used local therapeutic approach for intermediate to advanced-stage hepatocellular carcinoma(HCC),exhibiting considerable efficacy.However,the prevalence of postoperative pain highlights the importance of pain management.Owing to the limitations inherent in existing pain management strategies,this study investigates and assesses the analgesic effectiveness of a multimodal treatment protocol in mitigating pain after HAIC procedures.AIM To provide patients with a more comprehensive and effective pain management strategy.METHODS A total of 100 patients with primary HCC who underwent HAIC were randomly assigned to a control group(n=50)and a multimodal group(n=50).Baseline characteristics and perioperative data were collected.Upon enrollment,patients in the multimodal group received parecoxib(40 mg)30 minutes before HAIC,followed by 48 hours of patient-controlled analgesia with sufentanil.In contrast,the control group underwent standard preoperative preparation(psychological support)and received dezocine(5 mg)intraoperatively,with intravenous flurbiprofen(100 mg)administered every 12 hours for 48 hours postoperatively.RESULTS Compared to the control group,the multimodal analgesia group exhibited significantly lower resting and movement visual analog scale pain scores at postoperative 0,2,4,6,and 12 hours(P<0.05).Furthermore,the multimodal group experienced a reduced incidence of postoperative nausea and vomiting,as well as a lower overall frequency of adverse events,compared to the control group(P<0.05).Patient satisfaction was also significantly higher in the multimodal group than in the control group(P<0.05).CONCLUSION Our study demonstrates that multimodal analgesia is effective in reducing postoperative pain,minimizing adverse reactions,and improving patient satisfaction in HCC patients undergoing HAIC.This approach provides valuable clinical strategies for optimizing pain management in this patient population. 展开更多
关键词 advanced hepatocellular carcinoma Hepatic artery infusion chemotherapy Multimodal analgesia regimen Postoperative pain Pain improvement
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Advanced Predictive Analytics for Green Energy Systems: An IPSS System Perspective
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作者 Lei Shen Chutong Zhang +4 位作者 Yuwei Ge Shanyun Gu Qiang Gao Wei Li Jie Ji 《Energy Engineering》 2025年第4期1581-1602,共22页
The rapid development and increased installed capacity of new energy sources such as wind and solar power pose new challenges for power grid fault diagnosis.This paper presents an innovative framework,the Intelligent ... The rapid development and increased installed capacity of new energy sources such as wind and solar power pose new challenges for power grid fault diagnosis.This paper presents an innovative framework,the Intelligent Power Stability and Scheduling(IPSS)System,which is designed to enhance the safety,stability,and economic efficiency of power systems,particularly those integrated with green energy sources.The IPSS System is distinguished by its integration of a CNN-Transformer predictive model,which leverages the strengths of Convolutional Neural Networks(CNN)for local feature extraction and Transformer architecture for global dependency modeling,offering significant potential in power safety diagnostics.TheIPSS System optimizes the economic and stability objectives of the power grid through an improved Zebra Algorithm,which aims tominimize operational costs and grid instability.Theperformance of the predictive model is comprehensively evaluated using key metrics such as Root Mean Square Error(RMSE),Mean Absolute Percentage Error(MAPE),and Coefficient of Determination(R2).Experimental results demonstrate the superiority of the CNN-Transformer model,with the lowest RMSE and MAE values of 0.0063 and 0.00421,respectively,on the training set,and an R2 value approaching 1,at 0.99635,indicating minimal prediction error and strong data interpretability.On the test set,the model maintains its excellence with the lowest RMSE and MAE values of 0.009 and 0.00673,respectively,and an R2 value of 0.97233.The IPSS System outperforms other models in terms of prediction accuracy and explanatory power and validates its effectiveness in economic and stability analysis through comparative studies with other optimization algorithms.The system’s efficacy is further supported by experimental results,highlighting the proposed scheme’s capability to reduce operational costs and enhance system stability,making it a valuable contribution to the field of green energy systems. 展开更多
关键词 advanced predictive analytics green energy systems IPSS system CNN-transformer predictivemodel economic and stability optimization improved zebra algorithm
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Design strategy of advanced generation breeding population of Pinus tabuliformis based on genetic variation and inbreeding level
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作者 Chengcheng Zhou Fan Sun +2 位作者 Zhiyuan Jiao Yousry A.El-Kassaby Wei Li 《Forest Ecosystems》 2025年第4期607-618,共12页
The level of genetic variation within a breeding population affects the effectiveness of selection strategies for genetic improvement.The relationship between genetic variation level within Pinus tabuliformis breeding... The level of genetic variation within a breeding population affects the effectiveness of selection strategies for genetic improvement.The relationship between genetic variation level within Pinus tabuliformis breeding populations and selection strategies or selection effectiveness is not fully investigated.Here,we compared the selection effectiveness of combined and individual direct selection strategies using half-and full-sib families produced from advanced-generation P.tabuliformis seed orchard as our test populations.Our results revealed that,within half-sib families,average diameter at breast height(DBH),tree height,and volume growth of superior individuals selected by the direct selection strategy were higher by 7.72%,18.56%,and 31.01%,respectively,than those selected by the combined selection strategy.Furthermore,significant differences(P<0.01)were observed between the two strategies in terms of the expected genetic gains for average tree height and volume.In contrast,within full-sib families,the differences in tree average DBH,height,and volume between the two selection strategies were relatively minor with increase of 0.17%,2.73%,and 2.21%,respectively,and no significant differences were found in the average expected genetic gains for the studied traits.Half-sib families exhibited greater phenotypic and genetic variation,resulting in improved selection efficiency with the direct selection strategy but also introduced a level of inbreeding risk.Based on genetic distance estimates using molecular markers,our comparative seed orchard design analysis showed that the Improved Adaptive Genetic Programming Algorithm(IAPGA)reduced the average inbreeding coefficient by 14.36% and 14.73% compared to sequential and random designs,respectively.In conclusion,the combination of the direct selection strategy with IAPGA seed orchard design aimed at minimizing inbreeding offered an efficient approach for establishing advanced-generation P.tabuliformis seed orchards. 展开更多
关键词 Breeding population Parental selection strategies advanced generation seed orchard Pinus tabuliformis Seed orchard design improved Adaptive Genetic Programming Algorithm
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Chinese Society of Clinical Oncology Non-small Cell Lung Cancer(CSCO NSCLC)guidelines in 2024:key update on the management of early and locally advanced NSCLC
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作者 Siyuan Chen Zhijie Wang Boyang Sun 《Cancer Biology & Medicine》 2025年第3期191-196,共6页
The Chinese Society of Clinical Oncology Non-small Cell Lung Cancer(CSCO NSCLC)guidelines were first published in 2016,ranking among the earliest-released guidelines within the CSCO series.In 2020 the CSCO published s... The Chinese Society of Clinical Oncology Non-small Cell Lung Cancer(CSCO NSCLC)guidelines were first published in 2016,ranking among the earliest-released guidelines within the CSCO series.In 2020 the CSCO published separate guidelines for NSCLC and small cell lung cancer(SCLC)for the first time to improve clinical usability. 展开更多
关键词 improve clinical usability Clinical Usability Chinese Society Clinical Oncology Non Small Cell Lung Cancer Update CSCO NSCLC Guidelines Early NSCLC Locally advanced NSCLC
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A spatiotemporal evolution model of a short-circuit arc to a secondary arc based on the improved charge simulation method
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作者 丛浩熹 王宇轩 +2 位作者 乔力盼 苏文晶 李庆民 《Plasma Science and Technology》 SCIE EI CAS CSCD 2024年第1期62-73,共12页
The initial shape of the secondary arc considerably influences its subsequent shape.To establish the model for the arcing time of the secondary arc and modify the single-phase reclosing sequence,theoretical and experi... The initial shape of the secondary arc considerably influences its subsequent shape.To establish the model for the arcing time of the secondary arc and modify the single-phase reclosing sequence,theoretical and experimental analysis of the evolution process of the short-circuit arc to the secondary arc is critical.In this study,an improved charge simulation method was used to develop the internal-space electric-field model of the short-circuit arc.The intensity of the electric field was used as an independent variable to describe the initial shape of the secondary arc.A secondary arc evolution model was developed based on this model.Moreover,the accuracy of the model was evaluated by comparison with physical experimental results.When the secondary arc current increased,the arcing time and dispersion increased.There is an overall trend of increasing arc length with increasing arcing time.Nevertheless,there is a reduction in arc length during arc ignition due to short circuits between the arc columns.Furthermore,the arcing time decreased in the range of 0°-90°as the angle between the wind direction and the x-axis increased.This work investigated the method by which short-circuit arcs evolve into secondary arcs.The results can be used to develop the secondary arc evolution model and to provide both a technical and theoretical basis for secondary arc suppression. 展开更多
关键词 short-circuit arc secondary arc STOCHASTICITY improved charge simulation method arc time
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Dynamic Characteristics of Functionally Graded Timoshenko Beams by Improved Differential Quadrature Method
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作者 Xiaojun Huang Liaojun Zhang +1 位作者 Hanbo Cui Gaoxing Hu 《Computer Modeling in Engineering & Sciences》 SCIE EI 2024年第8期1647-1668,共22页
This study proposes an effective method to enhance the accuracy of the Differential Quadrature Method(DQM)for calculating the dynamic characteristics of functionally graded beams by improving the form of discrete node... This study proposes an effective method to enhance the accuracy of the Differential Quadrature Method(DQM)for calculating the dynamic characteristics of functionally graded beams by improving the form of discrete node distribution.Firstly,based on the first-order shear deformation theory,the governing equation of free vibration of a functionally graded beam is transformed into the eigenvalue problem of ordinary differential equations with respect to beam axial displacement,transverse displacement,and cross-sectional rotation angle by considering the effects of shear deformation and rotational inertia of the beam cross-section.Then,ignoring the shear deformation of the beam section and only considering the effect of the rotational inertia of the section,the governing equation of the beam is transformed into the eigenvalue problem of ordinary differential equations with respect to beam transverse displacement.Based on the differential quadrature method theory,the eigenvalue problem of ordinary differential equations is transformed into the eigenvalue problem of standard generalized algebraic equations.Finally,the first several natural frequencies of the beam can be calculated.The feasibility and accuracy of the improved DQM are verified using the finite element method(FEM)and combined with the results of relevant literature. 展开更多
关键词 Timoshenko beams functionally graded materials dynamic characteristics natural frequency improved differential quadrature method
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A flexible multiscale algorithm based on an improved smoothed particle hydrodynamics method for complex viscoelastic flows
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作者 Jinlian REN Peirong LU +2 位作者 Tao JIANG Jianfeng LIU Weigang LU 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI CSCD 2024年第8期1387-1402,共16页
Viscoelastic flows play an important role in numerous engineering fields,and the multiscale algorithms for simulating viscoelastic flows have received significant attention in order to deepen our understanding of the ... Viscoelastic flows play an important role in numerous engineering fields,and the multiscale algorithms for simulating viscoelastic flows have received significant attention in order to deepen our understanding of the nonlinear dynamic behaviors of viscoelastic fluids.However,traditional grid-based multiscale methods are confined to simple viscoelastic flows with short relaxation time,and there is a lack of uniform multiscale scheme available for coupling different solvers in the simulations of viscoelastic fluids.In this paper,a universal multiscale method coupling an improved smoothed particle hydrodynamics(SPH)and multiscale universal interface(MUI)library is presented for viscoelastic flows.The proposed multiscale method builds on an improved SPH method and leverages the MUI library to facilitate the exchange of information among different solvers in the overlapping domain.We test the capability and flexibility of the presented multiscale method to deal with complex viscoelastic flows by solving different multiscale problems of viscoelastic flows.In the first example,the simulation of a viscoelastic Poiseuille flow is carried out by two coupled improved SPH methods with different spatial resolutions.The effects of exchanging different physical quantities on the numerical results in both the upper and lower domains are also investigated as well as the absolute errors in the overlapping domain.In the second example,the complex Wannier flow with different Weissenberg numbers is further simulated by two improved SPH methods and coupling the improved SPH method and the dissipative particle dynamics(DPD)method.The numerical results show that the physical quantities for viscoelastic flows obtained by the presented multiscale method are in consistence with those obtained by a single solver in the overlapping domain.Moreover,transferring different physical quantities has an important effect on the numerical results. 展开更多
关键词 multiscale method improved smoothed particle hydrodynamics(SPH) dissipative particle dynamics(DPD) multiscale universal interface(MUI) complex viscoelastic flow
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3D finite element numerical simulation of advanced detection in roadway for DC focus method 被引量:7
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作者 邓小康 柳建新 +2 位作者 刘海飞 童孝忠 柳卓 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2013年第7期2187-2193,共7页
Within the roadway advanced detection methods, DC resistivity method has an extensive application because of its simple principle and operation. Numerical simulation of the effect of focusing current on advanced detec... Within the roadway advanced detection methods, DC resistivity method has an extensive application because of its simple principle and operation. Numerical simulation of the effect of focusing current on advanced detection was carried out using a three-dimensional finite element method (FEM), meanwhile the electric-field distribution of the point source and nine-point power source were calculated and analyzed with the same electric charges. The results show that the nine-point power source array has a very good ability to focus, and the DC focus method can be used to predict the aquifer abnormality body precisely. By comparing the FEM modelling results with physical simulation results from soil sink, it is shown that the accuracy of forward simulation meets the requirement and the artificial disturbance from roadway has no impact on the DC focus method. 展开更多
关键词 ROADWAY DC focus advanced detection finite element method
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Isolation of the Flanking Sequences Adjacent to Transgenic T-DNA in Brassica napus Genome by an Improved Inverse PCR Method 被引量:2
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作者 杨坤 吴学龙 +1 位作者 朗春秀 陈锦清 《Agricultural Science & Technology》 CAS 2010年第2期65-68,139,共5页
[Objective] The research aimed to isolate flanking sequences adjacent to the transgenic T-DNA in Brassica napus by an improved inverse PCR method.[Method] Using single clone of transgenic FS4 in Brassica napus as the ... [Objective] The research aimed to isolate flanking sequences adjacent to the transgenic T-DNA in Brassica napus by an improved inverse PCR method.[Method] Using single clone of transgenic FS4 in Brassica napus as the research materials,total DNA was extracted from transgenic Brassica napus by using modified CTAB method.After enzyme digestion and purification,self-joining was made.Two circles of nested PCR and the sequence alignment were carried out.[Result] A fragement with the size of 4.0 kb was amplified ... 展开更多
关键词 Inverse PCR(IPCR) Flanking sequences improved CTAB method Transgenic Brassica napus
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An Improved Method for DNA Extraction from the Faeces of Red Deer
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作者 日沙来提·吐尔地 艾斯卡尔·买买提 +2 位作者 日孜汗·阿布地艾尼 阿米拉·阿布来提 马合木提·哈力克 《Agricultural Science & Technology》 CAS 2012年第4期698-700,900,共4页
[Objective] To introduce an improved method for DNA extraction from the faeces of red deer. [Method] Based on the traditional method of CTAB lysis, we proposed an improved DNA extraction method according to the charac... [Objective] To introduce an improved method for DNA extraction from the faeces of red deer. [Method] Based on the traditional method of CTAB lysis, we proposed an improved DNA extraction method according to the characteristics of red deer faeces. [Result] This improved method extracted high-quality fecal DNA from Tianshan red deer and amplified the mitochondrial cytochrome b gene. With the muscle and fur DNA of red deer as the control, the sequencing results further con- firmed the reliability of the method. [Conclusion] The method requires no proteinase K in the process of extraction, and the extracted DNA can be used for PCR ampli- fication directly without the purification of DNA purification kit, thus, it is cost-saving. 展开更多
关键词 Red deer Noninvasive sampling improved method for DNA extraction Faecal DNA
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Design and analysis of an advanced thermal management system for the solar close observations and proximity experiments spacecraft 被引量:2
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作者 Liu Liu Kangli Bao +4 位作者 Jianchao Feng Xiaofei Zhu Haoyu Wang Xiaofeng Zhang Jun Lin 《Astronomical Techniques and Instruments》 CSCD 2024年第1期52-61,共10页
In this paper,the mission and the thermal environment of the Solar Close Observations and Proximity Experiments(SCOPE)spacecraft are analyzed,and an advanced thermal management system(ATMS)is designed for it.The relat... In this paper,the mission and the thermal environment of the Solar Close Observations and Proximity Experiments(SCOPE)spacecraft are analyzed,and an advanced thermal management system(ATMS)is designed for it.The relationship and functions of the integrated database,the intelligent thermal control system and the efficient liquid cooling system in the ATMS are elaborated upon.For the complex thermal field regulation system and extreme space thermal environment,a modular simulation and thermal field planning method are proposed,and the feasibility of the planning algorithm is verified by numerical simulation.A solar array liquid cooling system is developed,and the system simulation results indicate that the temperatures of the solar arrays meet the requirements as the spacecraft flies by perihelion and aphelion.The advanced thermal management study supports the development of the SCOPE program and provides a reference for the thermal management in other deep-space exploration programs. 展开更多
关键词 Solar Close Observations and Proximity Experiments Adaptive thermal control method Thermal field planning method Pumped liquid cooling system advanced thermal management system
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Water quality evaluation based on improved fuzzy matter-element method 被引量:23
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作者 Dongjun Liu Zhihong Zou 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2012年第7期1210-1216,共7页
For natural water, method of water quality evaluation based on improved fuzzy matter-element evaluation method is presented. Two important parts are improved, the weights determining and fuzzy membership functions. Th... For natural water, method of water quality evaluation based on improved fuzzy matter-element evaluation method is presented. Two important parts are improved, the weights determining and fuzzy membership functions. The coefficient of variation of each indicator is used to determine the weight instead of traditional calculating superscales method. On the other hand, fuzzy matter-elements are constructed, and normal membership degrees are used instead of traditional trapezoidal ones. The composite fuzzy matter-elements with associated coefficient are constructed through associated transformation. The levels of natural water quality are determined according to the principle of maximum correlation. The improved fuzzy matter-element evaluation method is applied to evaluate water quality of the Luokou mainstream estuary at the first ten weeks in 2011 with the coefficient of variatiola method determining the weights. Water quality of Luokou mainstream estuary is dropping from level I to level II. The results of the improved evaluation method are basically the same as the official water quality. The variation coefficient method can reduce the workload, and overcome the adverse effects from abnormal values, compared with the traditional calculating superscales method. The results of improved fuzzy matter- element evaluation method are more credible than the ones of the traditional evaluation method. The improved evaluation method can use information of monitoring data more scientifically and comprehensively, and broaden a new evaluation method for water quality assessment. 展开更多
关键词 water quality improved fuzzy matter-element evaluation method synthetic evaluation variation coefficient method normal membership Key words: water quality improved fuzzy matter-element evaluation method synthetic evaluation variation coefficient method normal membership
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An improved interpolating element-free Galerkin method with a nonsingular weight function for two-dimensional potential problems 被引量:15
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作者 王聚丰 孙凤欣 程玉民 《Chinese Physics B》 SCIE EI CAS CSCD 2012年第9期53-59,共7页
In this paper, an improved interpolating moving least-square (IIMLS) method is presented. The shape function of the IIMLS method satisfies the property of the Kronecker 5 function. The weight function used in the II... In this paper, an improved interpolating moving least-square (IIMLS) method is presented. The shape function of the IIMLS method satisfies the property of the Kronecker 5 function. The weight function used in the IIMLS method is nonsingular. Then the IIMLS method can overcome the difficulties caused by the singularity of the weight function in the IMLS method. The number of unknown coefficients in the trial function of the IIMLS method is less than that of the moving least-square (MLS) approximation. Then by combining the IIMLS method with the Galerkin weak form of the potential problem, the improved interpolating element-free Galerkin (IIEFG) method for two-dimensional potential problems is presented. Compared with the conventional element-free Galerkin (EFG) method, the IIEFG method can directly use the essential boundary conditions. Then the IIEFG method has higher accuracy. For demonstration, three numerical examples are solved using the IIEFG method. 展开更多
关键词 meshless method improved interpolating moving least-square method improved inter-polating element-free Galerkin method potential problem
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An improved boundary element-free method (IBEFM) for two-dimensional potential problems 被引量:8
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作者 任红萍 程玉民 张武 《Chinese Physics B》 SCIE EI CAS CSCD 2009年第10期4065-4073,共9页
The interpolating moving least-squares (IMLS) method is discussed first in this paper. And the formulae of the IMLS method obtained by Lancaster are revised. Then on the basis of the boundary element-free method (B... The interpolating moving least-squares (IMLS) method is discussed first in this paper. And the formulae of the IMLS method obtained by Lancaster are revised. Then on the basis of the boundary element-free method (BEFM), combining the boundary integral equation (BIE) method with the IMLS method, the improved boundary element-free method (IBEFM) for two-dimensional potential problems is presented, and the corresponding formulae of the IBEFM are obtained. In the BEFM, boundary conditions are applied directly, but the shape function in the MLS does not satisfy the property of the Kronecker ~ function. This is a problem of the BEFM, and must be solved theoretically. In the IMLS method, when the shape function satisfies the property of the Kronecker 5 function, then the boundary conditions, in the meshless method based on the IMLS method, can be applied directly. Then the IBEFM, based on the IMLS method, is a direct meshless boundary integral equation method in which the basic unknown quantity is the real solution of the nodal variables, and the boundary conditions can be applied directly and easily, thus it gives a greater computational precision. Some numerical examples are presented to demonstrate the method. 展开更多
关键词 moving least-squares approximation interpolating moving least-squares method mesh- less method improved boundary element-free method potential problem
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Improved normalization method for ductile fracture toughness determination based on dimensionless load separation principle 被引量:12
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作者 Chen Bao Lixun Cai +2 位作者 Kaikai Shi Chen Dan Yao Yao 《Acta Mechanica Solida Sinica》 SCIE EI CSCD 2015年第2期168-181,共14页
This study successfully deals with the inhomogeneous dimension problem of load separation assumption, which is the theoretical basis of the normalization method. According to the dimensionless load separation principl... This study successfully deals with the inhomogeneous dimension problem of load separation assumption, which is the theoretical basis of the normalization method. According to the dimensionless load separation principle, the normalization method has been improved by intro- ducing a forcible blunting correction. With the improved normalization method, the J-resistance curves of five different metallic materials of CT and SEB specimens are estimated. The forcible blunting correction of initial crack size plays an important role in the J-resistance curve estima- tion, which is closely related to the strain hardening level of material. The higher level of strain hardening leads to a greater difference in JQ determined by different slopes of the blunting line. If the blunting line coefficient recommended by ASTM E1820-11 is used in the improved nor- realization method, it will lead to greater fracture resistance than that processed by the blunting line coefficient recommended by ISO 12135-2002. Therefore, the influence of the blunting line on the determination of JQ must be taken into full account in the fracture toughness assessment of metallic materials. 展开更多
关键词 dimensionless load separation improved normalization method dimension inho-mogeneous J-resistance curve forcible blunting correction
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