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由活化测量数据求解中子能谱的“CRYSTAL-BALL”方法
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作者 许光道 《襄樊学院学报》 2003年第5期12-15,共4页
介绍了一种新的解谱法,它建立在中子谱的先验信息与中子谱的积分数据基础上. 利用先验谱对真实中子谱导数协方差极小,求得结果谱. 结果谱稳定,在探测响应灵敏区内,结果谱对初始谱的依赖性也是很弱的.
关键词 中子能谱 活化测量 先验信息
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DPF脉冲中子源中子产额的活化测量研究 被引量:5
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作者 郭志刚 韩旻 王昕 《清华大学学报(自然科学版)》 EI CAS CSCD 北大核心 2001年第3期43-46,共4页
活化测量是等离子体焦点 (DPF)中子源的窄脉冲、高注量率中子辐射产额的有效测量方法。为提高活化探测器的测量精度 ,采用了散射中子的屏蔽措施。详细讨论了探测器的标定方法 ,用饱和照射后截止的方法 ,在加速器中子源上给出了 3个探测... 活化测量是等离子体焦点 (DPF)中子源的窄脉冲、高注量率中子辐射产额的有效测量方法。为提高活化探测器的测量精度 ,采用了散射中子的屏蔽措施。详细讨论了探测器的标定方法 ,用饱和照射后截止的方法 ,在加速器中子源上给出了 3个探测距离下的标定曲线和标定系数。对标定中的物理问题 ,如探测器死时间对其测量范围的影响、银的两种衰变对标定结果的影响等进行了分析。估计了主要测量误差 。 展开更多
关键词 等离子体焦点 中子源 活化测量 中子辐射产额 脉冲辐射源 中子探测 注量率 探测距离 标定系数
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14MeV中子与铈元素的(n,2n)反应截面测量
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作者 朱传新 牟云峰 +5 位作者 陈渊 郑普 郭海萍 何铁 安如 王新华 《中国工程物理研究院科技年报》 2008年第1期40-41,共2页
在本工作中,铈元素14MeV中子(n,2n)反应截面通过^27Al(n,α)^24Na标准反应截面相对测量获得,^27Al(n,α)^24Na活化反应截面被推荐为一级放射计量标准截面,作为标准值被广泛用于放射剂量和活化测量中,尤其是在13.和14.9Me... 在本工作中,铈元素14MeV中子(n,2n)反应截面通过^27Al(n,α)^24Na标准反应截面相对测量获得,^27Al(n,α)^24Na活化反应截面被推荐为一级放射计量标准截面,作为标准值被广泛用于放射剂量和活化测量中,尤其是在13.和14.9MeV能区,该反应截面的不确定度小于1.0%,适合作为相对测量反应截面使用。 展开更多
关键词 反应截面测量 14MeV中子 铈元素 相对测量 活化测量 放射剂量 MEV能区 标准值
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单能中子源中低能成份对活化截面测量的影响 被引量:1
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作者 黄小龙 于伟翔 +6 位作者 韩晓刚 赵文荣 卢涵林 陈金象 施兆民 唐国有 张国辉 《高能物理与核物理》 CSCD 北大核心 1998年第12期1074-1081,共8页
对用单能中子源作活化截面测量时低能中子干扰的影响作了分析研究,并从测量的两种常用中子源T(d,n)4He和D(d,n)3He的中子源能谱中验证了这种定性分析.最后给出了两个比较典型的反应(58)Ni(n,P)(58)Co和(64)Zn(,P)... 对用单能中子源作活化截面测量时低能中子干扰的影响作了分析研究,并从测量的两种常用中子源T(d,n)4He和D(d,n)3He的中子源能谱中验证了这种定性分析.最后给出了两个比较典型的反应(58)Ni(n,P)(58)Co和(64)Zn(,P)(64)Cu反应的截面测量结果. 展开更多
关键词 单能中子源 低能中子 活化截面测量
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储层性能监测仪(RPM)及其应用 被引量:20
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作者 黄志洁 邱细斌 《石油仪器》 2004年第2期43-46,67,共4页
储层性能监测仪RPM (ReserviorPerformanceMonitor)是一种新的小直径高性能脉冲中子能谱仪。这种新型仪器的硬件系统具有脉冲中子俘获、脉冲中子能谱、脉冲中子持率、中子活化水流测量等多种工作模式。文章介绍了该仪器的基本测量原理 ... 储层性能监测仪RPM (ReserviorPerformanceMonitor)是一种新的小直径高性能脉冲中子能谱仪。这种新型仪器的硬件系统具有脉冲中子俘获、脉冲中子能谱、脉冲中子持率、中子活化水流测量等多种工作模式。文章介绍了该仪器的基本测量原理 ,以及利用RPM仪器的两种工作模式 (C/O模式和PNC模式 )确定剩余油饱和度及识别气层的解释方法及应用实例。 展开更多
关键词 储层性能监测仪 RPM 脉冲中子能谱仪 脉冲中子持率 中子活化水流测量 工作模式 剩余油 饱和度
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Activation measurement of neutron distribution in intermediate energy heavy ion target area
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作者 LiGui-Sheng WangJing 《Nuclear Science and Techniques》 SCIE CAS CSCD 1997年第3期166-169,共4页
ActivationmeasurementofneutrondistributioninintermediateenergyheavyiontargetareaLiGuiSheng,WangJing,ZhaoYanS... ActivationmeasurementofneutrondistributioninintermediateenergyheavyiontargetareaLiGuiSheng,WangJing,ZhaoYanSen,LiWenJian,... 展开更多
关键词 重离子靶区 中子分布 活化测量
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Conceptualizing and Measuring Economic Resilience of Resource-based Cities: Case Study of Northeast China 被引量:29
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作者 TAN Juntao ZHANG Pingyu +2 位作者 LO Kevin LI Jing LIU Shiwei 《Chinese Geographical Science》 SCIE CSCD 2017年第3期471-481,共11页
This paper develops a conceptual model and an indicator system for measuring economic resilience of resource-based cities based on the theory of evolutionary resilience and the related concepts of persistence, adaptat... This paper develops a conceptual model and an indicator system for measuring economic resilience of resource-based cities based on the theory of evolutionary resilience and the related concepts of persistence, adaptation, and transformation. Nineteen resource-based cities in Northeast China were analyzed using the indicator system. The results showed that Liaoning and Jilin provinces had higher economic resilience than Heilongjiang Province. Panjin, Benxi, and Anshan in Liaoning Province were the top three cities, while Shuangyashan and other coal-based cities in Heilongjiang Province ranked last. Metals-and petroleum-based cities had significantly higher resilience than coal-based cities. The differences in persistence, adaptability, transformation, and resilience among resource-based cities decreased since the introduction of the Northeast Revitalization Strategy in 2003. Forestry-based cities improved the most in terms of resilience, followed by metals-based and multiple-resource cities; however, resilience dropped for coal-based cities, and petroleum-based cities falling the most. The findings illustrate the importance and the way to develop a differentiated approach to improve resilience among resource-based cities. 展开更多
关键词 resource-based cities economic resilience Northeast China
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Optimization of Extraction Process of Olive Leaves by RSM and Evaluation of Antioxidant Capacity Measurements to the Mixtures 被引量:1
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作者 Zhengmao Cao Fanxi Meng Guanghua Zhao 《Journal of Food Science and Engineering》 2013年第10期525-533,共9页
Water extracts prepared from seven varieties of olive leaves native to the Mediterranean area but planted in Sichuan province, P.R. China, namely Frantoiao, Leccio, Ezhi, Picholine, Pendollino, Chenggu and Huaou 9#, w... Water extracts prepared from seven varieties of olive leaves native to the Mediterranean area but planted in Sichuan province, P.R. China, namely Frantoiao, Leccio, Ezhi, Picholine, Pendollino, Chenggu and Huaou 9#, were examined for their total phenonic and flavonoid contents, antioxidant capacity. Total phenolic and flavonoid content were measured by Folin-Ciocalteu method and a colorimetric method, respectively. ABTS+ method and FRAP were used for examining antioxidant activity. Response surface methodology (RSM) was used for optimizing the extract condition. Under the optimum condition, the total phenolic and flavonoid content of aqueous extracts of the dry olive leaves (DOL) ranged from 40.27 to 56.58 mg gallic acid (GAE)/g DOL and 21.59 to 33.72 mg catechin (CE)/g DOL in June, 34.31 to 52.81 mg GAE/g DOL and 17.11 to 23.53 mg CE/g DOL in November. The ABTS+ method and FRAP ranged from 0.23 to 0.35 mmol trolox (TE)/g DOL and 313.01 to 409.69 μmol Fe2+/g DOL in June, 0.19 to 0.30 mmol TE/g DOL and 254.69 to 418.10 pmol Fe2+/g DOL in November. Our results revealed that the total phenolic and flavonoid, or antioxidant capacity of the water extract were higher in June than November. Moreover, it was noticed that the antioxidant activity depends on the flavonoid and phenolic. 展开更多
关键词 Olive leaf extraction process ANTIOXIDANT RSM.
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A Modified Method for Measuring Root Iron Reductase Activity Under Normal Laboratory Conditions 被引量:3
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作者 ZHENGShao-Jian HEYun-Feng +1 位作者 TANGCai-Xian Y.MASAOKA 《Pedosphere》 SCIE CAS CSCD 2005年第3期363-368,共6页
Based on the strong chelating property of bathophenanthroline disulfonic acid (BPDS) with root chelate reductase activity is usually measured with a spectrophotometer using MES (2-morpholinoethanesulfonic acid) or HEP... Based on the strong chelating property of bathophenanthroline disulfonic acid (BPDS) with root chelate reductase activity is usually measured with a spectrophotometer using MES (2-morpholinoethanesulfonic acid) or HEPES (2-(4-(2-Hydroxyethyl)-1-piperazinyl) ethanesulfonic acid) buffer in the dark because of high autoreduction rate of in the presence of light. However, the exclusion of light is inconvenient, especially when analyzing a large number of samples. The objective of this study was to develop a new method for determination of root reductase activity under normal laboratory conditions using a suitable buffer composition and concentration to eliminate the autoreduction of A modified method using a Tris (2-amino-2-hydroxymethyl-1,3-propanediol) buffer at pH 7.5 instead of MES or HEPES buffer and a decreased FeEDTA (Fe ethylene diamine tetraacetic acid) concentration of 50 μmol L-1 was developed. The autoreduction of using the Tris buffer was undetectable for temperatures at 4 and 28 °C and was also much lower than that using the other buffers even with sunlight during measurement of reduction. Furthermore, the differences in reductase activity among 5 plant species and 14 red clover cultivars (Trifolium pratense L.) could be easily detected with the modified method. The method developed in this study to measure root Fe chelate reductase activity was not only effective and reliable but also easily managed under normal laboratory light conditions. 展开更多
关键词 autoreduction BUFFERS root chelate reductase activity
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The Research of the Influential Factors of Wearing Comfort of Functional Underwear
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作者 LIU Weimin XIE Hong 《International English Education Research》 2016年第5期24-27,共4页
Along with the rich material life, the change of the diet structure, people's shape also began to change.With performance m females is the body fat's increasing, the shape is not beautiful, therefore, body sculpting... Along with the rich material life, the change of the diet structure, people's shape also began to change.With performance m females is the body fat's increasing, the shape is not beautiful, therefore, body sculpting underwear has become the first choice for women to pursue beauty.To the requirement of sculpting body underwear is also becoming higher and higher for women.Comfortable and fashion is the sign of measuring a sculpting body underwear quality. This paper introduces the development history of sculpting body underwear, sculpting body underwear comfort evaluation index.And from the three aspects of the human body, clothing, environment do research to sculpting body underwear about the influence factors of wearing comfort.lt provides the certain reference value for consumers to purchase the sculpting body underwear and for enterprise to product sculpting body underwear. 展开更多
关键词 sculpting body underwear influencing factors pressure comfort
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