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An approach to evaluate the efficiency of γ-ray detectors to determine the radioactivity in environmental samples

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chinese Physics c 2014年第6期38卷 60-66页

作者： mohamed.S.Badawi Ahmed.m.El-Khatib Samah.m.Diab Sherif.S.Nafee Ekram.A.El-mallah Physics Department Faculty of Science Alexandria University 21511 Alexandria Egypt

This work provides an approach to determine the efficiency of T-ray detectors with a good accuracy in order to determine the concentrations of either naturally occurring or artificially prepared radionuclides. This approach is based on the efficiency transfer formula （ET）, the effective solid angles, the self- absorptions of the source matrix, the attenuation by the source container and the detector housing materials on the detector efficiency. The experimental calibration process was done using radioactive （cylindrical ＆ marinelli） sources, in different dimensions, that contain aqueous 152Eu radionuclide. The c.m.arison point to a fine agreement between the experimental measured and calculated efficiencies for the （NaI ＆ HPGe） detectors using volumetric radioactive sources.

关键词： y-ray detector efficiency efficiency transfer effective solid angles radioactive source

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2012防晒安全模式

中国化妆品 2012年第12期 34-37页

作者：可依 m.A.c

夏季已经来临．你首先要做的就是好好保护好自己。因为夏季猛烈的紫外线不但会剥夺你白皙净透的肌肤，还会加速肌肤的变化。想夏日少长几颗雀斑的话，誓要穷根究底出一个美丽真相！

关键词：安全模式防晒紫外线夏季肌肤

Repellent properties of cardiospermum,halicacabum Linn.(Family:Sapindaceae)plant leaf extracts against three important vector mosquitoes

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Asian Pacific Journal of Tropical Biomedicine 2012年第8期2卷 602-607页

作者： m Govindarajan R Sivakumar Division of Vector Biology and Phytochemistry Department of ZoologyAnnamalai University

Objective:To determine repellent activity of hexane,ethyl acetate,benzene,chloroform and methanol extract of cardiospermum halicacabum,(***) against culex quinque/ascialus(***),Aedes aegypti(***) and Anopheles slephensi(***). methods:Evaluation was carried out in a net cage(45 cm×30 cm×25 cm) containing 100 blood starved female mosquitoes of three mosquito species and were assayed in the laboratory condition by using the protocol of WHO 2005;The plant leaf crude extracts of *** was applied at 1.0,2.5,and 5.0 me/cm^2 separately in the exposed area of the fore *** ethanol served as ***:In this observation,the plant crude extracts gave protection against mosquito bites without any allergic reaction to the test person,and also,the repellent activity was dependent on the strength of the plant *** tested plant crude extracts had exerted promising repellent against all the three ***:From the results it can be concluded the crude extract of *** was potential for controlling ***, *** and *** mosquitoes.

关键词： Repellency cardiospermum halicacabum culex quinquefasciatus Aedes aegypti Anopheles stephensi

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后洛丽塔风格正当道

中国化妆品 2008年第13期 44-45页

作者：芳芳 m.A.c 美谛高丝

甜美娃娃脸的洛丽塔曾经火遍全球，如今帅气的中性风潮正席卷整个时尚圈。“王子”般的美女正在蹿红，气质冷峻、外形中性、个性鲜明，她们撼动着设计师的灵感。中性服装大热特热，满T台的雌雄莫辨，这就是“后洛丽塔”。

关键词：风格塔中性风设计师

molecular cytogenetics in Hematological malignancies

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Molecular Cytogenetics in Hematological Malignancies

中华医学会第七次全国检验医学学术会议

作者： Professor of Pediatrics and Pathology Director,cytogenetics The University of Utah Zhong chen,m.D.,F.A.c.m.G.

chromosomal changes have been established in a wide spec- trum of cancers,ranging from the various leukemias to lymphomas to solid *** addition to the clinical application of these cytoge- netic changes,the establishment of specific chromosomes or chromo- somal bands affected by these changes has led molecular biologists to recognize,characterize and isolate genes that are affected by and possibly responsible for the conditions *** information has

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荔枝生殖生长的模式和控制(综述)

亚热带植物科学 1984年第2期 63-68页

作者： c.m.menzel 徐雄

通常,荔枝产量与花量之间未见相关。这是因为早花过多,特别是早期着果,而导致成花到果实成熟期间的落花落果。有可能是雌、雄花比率低、缺少授粉昆虫、授粉不良、花粉生活力低以及花粉管生长受阻,均会减少着果率,而果实发育不良会降低... 详细信息

通常,荔枝产量与花量之间未见相关。这是因为早花过多,特别是早期着果,而导致成花到果实成熟期间的落花落果。有可能是雌、雄花比率低、缺少授粉昆虫、授粉不良、花粉生活力低以及花粉管生长受阻,均会减少着果率,而果实发育不良会降低果实的最终生长量。有关基因型与环境因素(温度、土壤水分、相对湿度和矿质营养)对花、果的生长和脱落的影响,需要进行详细的研究。提高着果率的生产技术有:品种选择、开花和果实早期生长期间控制氮肥(以减少营养生长),以及保持植株的水分状况(灌溉、人工喷雾和设置风障)。

关键词：荔枝树日烧病裂果果实成熟落花落果土壤水分雌花植株植物生理性病土壤水土壤成分座果率着果率花粉萌发生殖生长假种皮

Application of Different Kinetic.m.thods to the Thermogravimetric Analysis of Kenaf（Hibiscus cannabinus）

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Application of Different Kinetic Methods to the Thermogravim...

幼年特发性关节炎：扩散加权mRI评估膝关节炎

The 18th European Biomass conference and Exhibition

作者： González J.F. Encinar J.m. Román S. Rayo m.c.

The objective of this work was to investigate the thermal dec.m.osition process of kenaf（Hibiscus cannabinus） and to determine their activation energy values associated through a dynamic thermogravimetric analysis by model-free methods. The pyrolysis of kenaf has been carried out by means of thermogravimetric analysis in Ar atmosphere. Four heating rates were used（5-10-20-40 K min-1） up to a final temperature of 700 oc. The activation energy values were calculated as a function of the extent of conversion during the pyrolysis process by means of Friedman, Kissinger-Akahira-Sunose and Flynn–Wall–Ozawa isoconversional methods. The results showed that there are small differences between the activation energy values obtained from the three methods. Also, a relationship between the activation energy and the conversion reached was found.

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国际医学放射学杂志 2020年第4期 484-485页

作者： A.m.Barendregt V.mazzoli E.c.V.Gulik D.S.meinema A.N.S.Rashid c.m.Nusman 夏志鹏 Department of Radiology and Nuclear medicine Amsterdam University Medical Centers

扩散加权成像(DWI)可以显示关节炎的滑膜炎性病变。目的与临床诊断对照,探讨DWI对关节炎的诊断准确性,并比较DWI与增强mRI对滑膜炎症的检测效能。材料

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自动补偿温漂的直流放大器

宇航计测技术 1989年第6期8卷 75-77页

作者： R.c.S.Freire m.Abignoli A.m.N.Lima G.S.Deep 阎军

本文介绍了一种用普通运放构成的自动补偿温漂的直流应变电桥放大电路。放大器的工作分两步,一是自动补偿,二是放大输入信号。输入补偿是通过开关使电桥的激励源周期切换到零电位实现的,切换频率约为100Hz。因此,限定输入信号的最高频率... 详细信息

本文介绍了一种用普通运放构成的自动补偿温漂的直流应变电桥放大电路。放大器的工作分两步,一是自动补偿,二是放大输入信号。输入补偿是通过开关使电桥的激励源周期切换到零电位实现的,切换频率约为100Hz。因此,限定输入信号的最高频率为8Hz。放大器的增益为5000,当温度变化40℃时,测得输出电压漂移约1mV。

关键词：直流放大器自动补偿温漂

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