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NEA加速器驱动系统(ADS)基准体系散裂中子相对裂变中子重要性的研究
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作者 时磊 景桂芬 《四川大学学报(自然科学版)》 CAS CSCD 北大核心 2011年第1期139-141,共3页
加速器驱动次临界系统(ADS)在生产能量、增殖核燃料和嬗变高放废物等方面具有良好的应用前景,在国际上受到广泛的重视.在ADS系统的设计中,外源中子相对裂变中子的重要性是影响外源中子利用价值的重要因素.本文通过对NEA加速器驱动系统(A... 加速器驱动次临界系统(ADS)在生产能量、增殖核燃料和嬗变高放废物等方面具有良好的应用前景,在国际上受到广泛的重视.在ADS系统的设计中,外源中子相对裂变中子的重要性是影响外源中子利用价值的重要因素.本文通过对NEA加速器驱动系统(ADS)基准体系的MCNP5模拟计算,给出了体系的散裂中子相对于裂变中子重要性的具体计算方法和结果,为ADS系统的研究提供了参考. 展开更多
关键词 ADS 基准体 MCNP模拟 相对重要性 裂变能谱
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西峰油田长8油层组高分辨率层序地层分析 被引量:1
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作者 王峰 田景春 +2 位作者 陈蓉 夏青松 刘若冰 《成都理工大学学报(自然科学版)》 CAS CSCD 北大核心 2006年第6期581-586,共6页
运用高分辨率层序地层学的短期基准面旋回原理,详细分析了鄂尔多斯盆地西峰油田长8油组辫状河三角洲前缘的叠加水下分流河道、复合式河口坝、叠加河口坝、滑塌体及浊积扇砂体短期基准面旋回的叠加样式及储层成因。研究表明这五类砂体明... 运用高分辨率层序地层学的短期基准面旋回原理,详细分析了鄂尔多斯盆地西峰油田长8油组辫状河三角洲前缘的叠加水下分流河道、复合式河口坝、叠加河口坝、滑塌体及浊积扇砂体短期基准面旋回的叠加样式及储层成因。研究表明这五类砂体明显受到基准面升降、可容纳空间和沉积物补给量比值的控制。在此基础上探讨了不同砂体组合在长8层序地层格架中的展布规律。 展开更多
关键词 辫状河三角洲前缘 短期基准面旋回 成因 西峰油田 鄂尔多斯盆地
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通用小型汽油机噪声测试方法解析 被引量:1
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作者 刘琳 毛文刚 +2 位作者 杨锐 刘建辉 杨建伟 《内燃机》 2019年第3期44-46,共3页
本文根据噪声测试标准GB/T 1859.1-2015《往复内燃机声压法声功率级的测定第1部分:工程法》介绍了通用小型汽油机噪声测试声学环境的要求,噪声测试基准体选取,传声器位置布置技术特点,结合噪声测试试验中仪器设备的应用、数据的采集和处... 本文根据噪声测试标准GB/T 1859.1-2015《往复内燃机声压法声功率级的测定第1部分:工程法》介绍了通用小型汽油机噪声测试声学环境的要求,噪声测试基准体选取,传声器位置布置技术特点,结合噪声测试试验中仪器设备的应用、数据的采集和处理,进一步探讨通用小型汽油机噪声测试技术方法,为噪声测试技术提供有力的参考。 展开更多
关键词 通用小型汽油机 噪声测试 声学环境 基准体 传声器位置
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Sedimentary system characteristics and depositional filling model of Upper Permian——Lower Triassic in South Yellow Sea Basin 被引量:6
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作者 YUAN Yong CHEN Jian-wen +3 位作者 ZHANG Yin-g ZHANG Yu-xi LIANG Jie ZHANG Peng-hui 《Journal of Central South University》 SCIE EI CAS CSCD 2018年第12期2910-2928,共19页
In the South Yellow Sea Basin,Mesozoic–Paleozoic marine strata are generally well developed with large thickness,and no substantial breakthroughs have been made in hydrocarbon exploration.Through research,it is belie... In the South Yellow Sea Basin,Mesozoic–Paleozoic marine strata are generally well developed with large thickness,and no substantial breakthroughs have been made in hydrocarbon exploration.Through research,it is believed that the Upper Permian–Lower Triassic can be regarded as a long-term base-level cycle.Based on drilling data,characteristics of the lithology–electric property combination cyclicity,and the special lithology,the long-term base-level cycle was divided into five medium-term base-level cycles(MC1–MC5).On this basis,the Permian–Triassic sedimentary systems and their filling model were analyzed in accordance with the change of base-level cycle and transition of sedimentary environment,as well as characteristics of the drilling sedimentary facies and seismic facies.The results show that there were six sedimentary systems(fluvial,delta,tidal flat,open platform,restricted platform,and continental shelf)developed in the Upper Permian–Lower Triassic,the sedimentary systems were distributed such that the water was deep in the northwest and shallow in the southeast,and there were two base-level cycle filling models(a relatively stable tidal flat facies and a rapidly transgressive continental shelf facies to stable platform facies)developed in the Upper Permian–Lower Triassic.These models can provide a basis for evaluation of the Mesozoic–Paleozoic hydrocarbon geology in the South Yellow Sea Basin. 展开更多
关键词 sequence base-level cycle sedimentary system depositional filling model Upper Permian–Lower Triassic South Yellow Sea Basin
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Application of Equilibrium Partitioning Approach to the Derivation of Sediment Quality Guidelines for Metals in Dianchi Lake 被引量:9
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作者 CHEN Yun-Zeng YANG Hao +3 位作者 ZHANG Zhen-Ke QIN Ming-Zhou JIN Feng LU Jun-Jie 《Pedosphere》 SCIE CAS CSCD 2007年第3期284-294,共11页
For the past 20 years, numerous studies have been carried out on the application of equilibrium partitioning approach (EqPA) for the derivation of sediment quality guidelines (SQGs). However, for metals, few Equil... For the past 20 years, numerous studies have been carried out on the application of equilibrium partitioning approach (EqPA) for the derivation of sediment quality guidelines (SQGs). However, for metals, few Equilibrium-partitioning- based numerical SQGs have been developed or are currently available because of the confounding factors mediating the bioavailability of metals. A study was conducted at Dianchi Lake, which is a heavily eutrophicated lake on the Yunnan- Guizhou Plateau, China with the focus on the measurement of partitioning coefficient (Kp) and SQGs derivation and normalization to acid volatile sulfide (AVS), fine material, and organic carbon. Using new normalization methods, SQGs were formulated for seven metals including copper, zinc, lead, cadmium, chromium, mercury, and arsenic in Dianchi Lake. In Dianchi Lake sediments, the fine material contributed 25.4%-36.0% to the SQG values, with the largest contribution to the SQG value of mercury; AVS contributed 2.9%-75.0% to the SQG values, with the largest contribution to the SQG value of cadmium. This indicated that the fine material and the AVS were the most important controlling factors to the bioavailability of mercury and caximium, respectively. The contribution of total organic carbon (TOC) to the SQG values of copper and leaxi was 3.8% and 7.1%, respectively, indicating that at relatively lower concentrations, the contribution of TOC was not significant. In addition to normalization methods, appropriate procedures for the application of EqPA including sample collection, storage, and analysis are also essential to improve the reliability of SQGs. The normalized Dianchi Lake SQGs were higher than most of the empirically based SQGs developed in North America, but lower than Hong Kong interim SQGs except for cadmium and arsenic. The differences could be attributed to the approaches used for derivation of SQGs and the water quality criteria adopted and the differences in the physical and chemical characteristics of the sediments. 展开更多
关键词 acid volatile sulfide fine material normalization method organic carbon sediment quality guidelines
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Experience of implanting fiducial markers for 504 cases with body malignant solid tumors
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作者 Sujing Zhang Yu Li +4 位作者 Huijun Xu Xiao Yang Liyan Song Xiaoliang Liu Hao Wu 《The Chinese-German Journal of Clinical Oncology》 CAS 2014年第3期119-122,共4页
Objective:The purpose of the study is to investigate the technical points,effects and complications of fiducial marker implantation within target areas before the CyberKnife treatment on body malignant solid tumors.Me... Objective:The purpose of the study is to investigate the technical points,effects and complications of fiducial marker implantation within target areas before the CyberKnife treatment on body malignant solid tumors.Methods:Five hundred and four cases of patients with body malignant solid tumors accepted fiducial implantation within target areas under CT guidance before the treatment of CyberKnife.Observe the complications and effect.Results:Among the 504 cases,500 cases successfully accepted the implantation(a success rate of 99.2%).158 patients felt pain at the punctured sites and 3 patients had tachycardia.33 patients had abdominal pain after the surgery due to a small amount of bleeding in the needle passage during liver puncturing process.Among the 19 lung cancer patients who accepted lung paracentesis,1 case had light pneumothorax and 1 case got light haemothorax.Among the 453 patients who accepted liver paracentesis,6 had fiducial migration.Conclusion:The method of fiducial implantation within target areas before treating body malignant solid tumor with CyberKnife is minimally invasive and comparatively secure. 展开更多
关键词 CYBERKNIFE fiducial CT guidance COMPLICATION
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Review of Electric Vehicle Charging Infrastructure Standards Svstem
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作者 Wu Shangjie Luo Xiaoying 《China Standardization》 2011年第4期59-62,共4页
Based on electric vehicle technology and industrial development, this paper introduces the international and domestic situation of electric vehicle charging infrastructure standards, analyzes the problems existing in ... Based on electric vehicle technology and industrial development, this paper introduces the international and domestic situation of electric vehicle charging infrastructure standards, analyzes the problems existing in the standard system in China, and suggestions are put forward for the future direction and development of electric vehicle charging infrastructure standards. 展开更多
关键词 electric vehicle CHARGING STANDARD
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Standards System and Evaluation Indicators System for Environmental Protection Products
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作者 Huang Jin Lin Ling Wang Xiuteng 《China Standardization》 2010年第6期17-25,共9页
Environmental protection products and equipment are important substance basis and insurance which provide supporting for to the realization of the strategic objective of reduced energy use and emissions while improvin... Environmental protection products and equipment are important substance basis and insurance which provide supporting for to the realization of the strategic objective of reduced energy use and emissions while improving the resource economy & environmental kindly society building, as well as the sustainable development economy and environment in a sustainable fashion. Here, the framework of the standards system and evaluation indicators system for environmental protection products are described based on the present deficiencies in independent innovation, lower levels of standardization, and poor operating effectiveness of such equipment in China with a goal of forcing the development of standardization, seriation and currency used in the environmental protection industry. The results presented here should serve as a reference for the promotion of quality and effectiveness in environmental protection products and equipments. 展开更多
关键词 Environmental Protection Products Standards System Evaluation Indicators System
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桁架结构极限承载力分析的弹性模量缩减法 被引量:4
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作者 张伟 张阳 杨绿峰 《应用基础与工程科学学报》 EI CSCD 北大核心 2017年第1期129-140,共12页
为提高桁架结构极限承载力分析的计算效率和精度,建立了一种基于基准体的弹性模量缩减法.在弹性模量缩减法基础上引入了代表失效模式的基准体概念,提出了以单元承载比大小为依据的基准体失效排序策略,并考虑桁架整体破坏和局部破坏极限... 为提高桁架结构极限承载力分析的计算效率和精度,建立了一种基于基准体的弹性模量缩减法.在弹性模量缩减法基础上引入了代表失效模式的基准体概念,提出了以单元承载比大小为依据的基准体失效排序策略,并考虑桁架整体破坏和局部破坏极限状态时的失效模式特性,提出了基准体失效构件选取原则,建立了桁架基准体的识别方法;同时根据功能互等原理推导了用轴力表达的极限承载力计算方法,进而考虑基准体的影响,建立了桁架结构极限承载力分析的弹性模量缩减法.算例分析表明,本文方法具有良好的计算精度和效率. 展开更多
关键词 桁架结构 极限承载力 弹性模量缩减法 基准体
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In-situ U-Pb dating of uraninite by fs-LA-ICP-MS 被引量:26
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作者 ZONG KeQing CHEN JinYong +4 位作者 HU ZhaoChu LIU YongSheng LI Ming FAN HongHai MENG YanNing 《Science China Earth Sciences》 SCIE EI CAS CSCD 2015年第10期1731-1740,共10页
In this study, the Pb/U fractionation between zircon and uraninite during femtosecond Laser Ablation Inductively Coupled Plasma Mass Spectrometry (fs-LA-ICP-MS) analysis was studied in detail. The results show signi... In this study, the Pb/U fractionation between zircon and uraninite during femtosecond Laser Ablation Inductively Coupled Plasma Mass Spectrometry (fs-LA-ICP-MS) analysis was studied in detail. The results show significant Pb/U fractionation between zircon and uraninite during fs-LA-ICP-MS analysis that when calibrated against the zircon standard M257, the obtained U-Pb age of the Chinese national uraninite standard GBW04420 is 17% older than the recommended value. Thus, the accurate in-situ U-Pb dating of uraninite by LA-ICP-MS requires matrix-matched external standards for calibration. Uraninite in thin sections of two U-mineralized leucogranite from the Gaudeanmus in Namibia was analyzed by a fs-LA-ICP-MS equipped with a Signal Smooth Device (SSD), using laser spot and frequency of 10 μm and 1 Hz, respectively. When calibrated using GBW04420 as the external standard, two samples give weighted mean 2066pb/238U ages of 504±3 Ma (2σ, n=21) and 503±3 Ma (2σ, n=22), and only one of two samples yields a concordia U-Pb age of 507±1 Ma (2or, n=21). These results are consistent with ID-TIMS U-Pb ages of 509±1 and 508±12 Ma and are also indistinguishable from zircon U-Pb upper intercept ages of 506±33 Ma (2σ, n=29) and 501±51 Ma (2σ, n=29). The present study shows that in-situ U-Pb dating of uraninite can deliver more reliable formation ages of the deposit than dating coeval high-U zircon because the latter commonly suffer significant Pb loss after formation. Our results confirm that GBW04420 is an ideal matrix matching standard for in-situ U-Pb dating of uraninite. 展开更多
关键词 URANINITE fs-LA-ICP-MS U-Pb dating element fractionation Rossing GBW04420
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