Different from traditional aggregation method, the unreliable buffers are originally considered and a more general aggregation method is offered, in which not only the unreliable buffers are considered, but also the p...Different from traditional aggregation method, the unreliable buffers are originally considered and a more general aggregation method is offered, in which not only the unreliable buffers are considered, but also the probabilities of system states are obtained by a discrete model rather than the continuous flow model of unreliable manufacturing systems. The solution technique is offered to get the system sate probabilities. The method advances the traditional system aggregation techniques. Numerical results specify the extended aggregation method and also show that the unreliable limited buffers have a strong impact on the efficiency of the production lines.展开更多
[Objective] This study aimed to investigate a reliable method for DNA ex- traction from Wusuli raccoon dog＇s hair. [Method] Several DNA extraction methods were used to extract DNA from Wusuli raccoon dog hair, includ...[Objective] This study aimed to investigate a reliable method for DNA ex- traction from Wusuli raccoon dog＇s hair. [Method] Several DNA extraction methods were used to extract DNA from Wusuli raccoon dog hair, including Chelex-100 method, PCR buffer method, organic phenol-chloroform method and centrifugal col- umn type kit method. The extracted DNA was analyzed by using PCR amplification and electrophoresis to compare these four DNA extraction methods. [Result] Accord- ing to the results of spectrophotometer detection and gel electrophoresis, nucleic acid extracted by Chetex-100 method had proteins and other impurities; nucleic acid ex- tracted by PCR buffer method was low in concentration; however, DNA extracted by organic phenol-chloroform method and centrifugal column type kit was high in con- centration with no impurity band. [Conclusion] This study had laid the strong founda- tion of scientific theory to further explore the efficient and simple method for extracting DNA from Wusuli raccoon dog hair follicle.展开更多
Aimed at the difficulties in analyzing the buffer characteristics of airbag system by using thermodynamic or experimental method only,the finite element method was used to establish nonlinear models for heavy equipmen...Aimed at the difficulties in analyzing the buffer characteristics of airbag system by using thermodynamic or experimental method only,the finite element method was used to establish nonlinear models for heavy equipment and its airbag system.The models' efficiency and correctness were validated by using on-site experiment data in vehicle airdrop landing.The simulation results agree very well with the experiment results.Then,the environment adaptability of airbag system of heavy equipment under high-altitude condition was studied by using the models.Finally,some solutions were given to solve the overturn problem in the landing.展开更多
当前长江大保护已进入生态修复的关键期。作为流域生态修复的核心手段,河湖缓冲带与水生植被修复技术在国内外已形成大量成果,亟须立足绿色低碳视角开展系统性评估,遴选适用于长江流域的高效、实用技术。基于此,对中国知网及Web of Scie...当前长江大保护已进入生态修复的关键期。作为流域生态修复的核心手段,河湖缓冲带与水生植被修复技术在国内外已形成大量成果,亟须立足绿色低碳视角开展系统性评估,遴选适用于长江流域的高效、实用技术。基于此,对中国知网及Web of Science数据库中河湖缓冲带与水生植被修复技术相关研究进行热点分析,解析技术研究趋势;同时,收集整理国家水体污染控制与治理科技重大专项等项目中已工程应用的技术62项,提炼其关键工程参数,建立适用技术评估方法对62项技术进行综合评估,并利用雷达图对4项典型优秀技术进行解析。结果显示:1)近20多年来,国内外河湖缓冲带研究热点集中在缓冲带拦截功能、净化机理、污染原因解析、布局优化与管理方面,而水生植被研究热点集中在生态系统重建、协同修复技术、不同植被类型对水质改善的作用以及污染物去除机制方面。2)从技术就绪度、经济、减污降碳、生态环境4个维度构建河湖缓冲带与水生植被修复技术评估指标体系,采用“熵权+TOPSIS”法进行综合评估,以相对贴近度划分技术评估等级;3)应用构建的技术评估方法筛选出适用于长江流域的绿色低碳技术32项,包括河流缓冲带修复技术9项、湖泊缓冲带修复技术9项、湿地生态修复技术6项、水生植被修复技术8项,其中有6项技术得分在0.75以上,等级为优秀。4)4项典型优秀技术在技术就绪度、生态效益等方面表现突出,具备推广应用的基础,但在运行成本及污染负荷去除性能方面尚有提升空间。研究成果可为长江流域水生态修复提供绿色低碳技术支撑。展开更多
基金Great Technology Innovation of Gansu Province,China (No.2GS063-A52-005-01)Natural Science Foundation of Gansu Province,China (No.3ZS062-B25-034)Research Item of Education Department of Gansu Province,China (No.0703-06)
文摘Different from traditional aggregation method, the unreliable buffers are originally considered and a more general aggregation method is offered, in which not only the unreliable buffers are considered, but also the probabilities of system states are obtained by a discrete model rather than the continuous flow model of unreliable manufacturing systems. The solution technique is offered to get the system sate probabilities. The method advances the traditional system aggregation techniques. Numerical results specify the extended aggregation method and also show that the unreliable limited buffers have a strong impact on the efficiency of the production lines.
基金Supported by National Natural Science Foundation of China (31072018)~~
文摘[Objective] This study aimed to investigate a reliable method for DNA ex- traction from Wusuli raccoon dog＇s hair. [Method] Several DNA extraction methods were used to extract DNA from Wusuli raccoon dog hair, including Chelex-100 method, PCR buffer method, organic phenol-chloroform method and centrifugal col- umn type kit method. The extracted DNA was analyzed by using PCR amplification and electrophoresis to compare these four DNA extraction methods. [Result] Accord- ing to the results of spectrophotometer detection and gel electrophoresis, nucleic acid extracted by Chetex-100 method had proteins and other impurities; nucleic acid ex- tracted by PCR buffer method was low in concentration; however, DNA extracted by organic phenol-chloroform method and centrifugal column type kit was high in con- centration with no impurity band. [Conclusion] This study had laid the strong founda- tion of scientific theory to further explore the efficient and simple method for extracting DNA from Wusuli raccoon dog hair follicle.
文摘Aimed at the difficulties in analyzing the buffer characteristics of airbag system by using thermodynamic or experimental method only,the finite element method was used to establish nonlinear models for heavy equipment and its airbag system.The models' efficiency and correctness were validated by using on-site experiment data in vehicle airdrop landing.The simulation results agree very well with the experiment results.Then,the environment adaptability of airbag system of heavy equipment under high-altitude condition was studied by using the models.Finally,some solutions were given to solve the overturn problem in the landing.
文摘当前长江大保护已进入生态修复的关键期。作为流域生态修复的核心手段,河湖缓冲带与水生植被修复技术在国内外已形成大量成果,亟须立足绿色低碳视角开展系统性评估,遴选适用于长江流域的高效、实用技术。基于此,对中国知网及Web of Science数据库中河湖缓冲带与水生植被修复技术相关研究进行热点分析,解析技术研究趋势;同时,收集整理国家水体污染控制与治理科技重大专项等项目中已工程应用的技术62项,提炼其关键工程参数,建立适用技术评估方法对62项技术进行综合评估,并利用雷达图对4项典型优秀技术进行解析。结果显示:1)近20多年来,国内外河湖缓冲带研究热点集中在缓冲带拦截功能、净化机理、污染原因解析、布局优化与管理方面,而水生植被研究热点集中在生态系统重建、协同修复技术、不同植被类型对水质改善的作用以及污染物去除机制方面。2)从技术就绪度、经济、减污降碳、生态环境4个维度构建河湖缓冲带与水生植被修复技术评估指标体系,采用“熵权+TOPSIS”法进行综合评估,以相对贴近度划分技术评估等级;3)应用构建的技术评估方法筛选出适用于长江流域的绿色低碳技术32项,包括河流缓冲带修复技术9项、湖泊缓冲带修复技术9项、湿地生态修复技术6项、水生植被修复技术8项,其中有6项技术得分在0.75以上,等级为优秀。4)4项典型优秀技术在技术就绪度、生态效益等方面表现突出,具备推广应用的基础,但在运行成本及污染负荷去除性能方面尚有提升空间。研究成果可为长江流域水生态修复提供绿色低碳技术支撑。
