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Gaussian Weighted Trajectory Method Ⅳ： No Rainbow Effect in Practice

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Chinese Journal of Chemical Physics 2009年第2期22卷 210-214页

作者： l. Bonnet Institut des Sciences Moléulaires Université Bordeaux 1 351 Cours de la Libéation 33405 Talence Cedex France

The Gaussian weighted trajectory method （GWTM） is a practical implementation of classical S matrix theory （CSMT） in the random phase approximation, CSMT being the first and simplest semi-classical approach of molecular collisions, developped in the early seventies. Though very close in spirit to the purely classical description, GWTM accounts to some extent for the quantization of the different degrees-of-freedom involved in the processes. While CSMT may give diverging final state distributions, in relation to the rainbow effect of elastic scattering theory, GWTM has never led to such a mathematical catastrophe. The goal of the present note is to explain this finding.

关键词： Gaussian weighted trajectory method Classical S matrix theory Rainbow effect

Effect of bias voltage on microstructure of DC magnetron sputtered Al coatings on uranium

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中国有色金属学会会刊：英文版 2004年第Z1期14卷 247-250页

作者： lü Xue-chao China Acad. of Eng. Phys. Mianyang 621900 China

The effect of different bias voltages on microstructure of Al coatings on uranium was investigated by la-sing scanning electron microscope (SEM), X-ray diffraction (XRD) and X-ray stress analyzer, respectively. The results indicate that the microstructure is influenced strongly by bias voltage. At low bias voltages, especially at -100 V, the structure of Al coatings is more densely packed than that at high bias voltages of -300 V and -400 V, where the structure looks like open dentritic. On the whole, the peak (111) orientation is predominant with the increase of bias voltage, but at -400 V, the diffractive intensity of main peaks (111) and (200) is close to the standard reference. The residual stress on Al coatings surface is small, which has a change from tensile to compressive stress with the increase of bias voltage.

关键词： Bias voltage Coatings microstructure Magnetron sputtering deposition Uranium

A geometric interpretation of the transition density of a symmetric lévy process

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Science China Mathematics 2012年第6期55卷 1099-1126页

作者： JACOB Niels KNOPOVA Victorya lANDWEHR Sandra SCHIllING Renél. Department of Mathematics Swansea UniversitySingleton ParkSwansea SA28PPUK V.M.Glushkov Institute of Cybernetics NAS of Ukraine 03187KievUkraine Heinrich Heine University Düsseldorf German Diabetes Center at the Heinrich Heine University DüsseldorfLeibniz Center for Diabetes ResearchInstitute of Biometrics and EpidemiologyAuf'm Hennekamp 6540225 DüsseldorfGermany Institut für Mathematische Stochastik Technische Universität Dresden01062 DresdenGermany

We study for a class of symmetric levy processes with state space R^n the transition density pt（x） in terms of two one-parameter families of metrics, （dt）t〉o and （δt）t〉o. The first family of metrics describes the diagonal term pt （0）; it is induced by the characteristic exponent ψ of the levy process by dr（x, y） = √tψ（x - y）. The second and new family of metrics 6t relates to √tψ through the formula exp（-δ^2t（x,y））=F[e^-tψ/pt（0）]（x-y）,where Y denotes the Fourier transform. Thus we obtain the following ＂Gaussian＂ representation of the tran- sition density： pt（x） = pt（O）e^-δ^2t（x,0） where pt（O） corresponds to a volume term related to √tψ and where an ＂exponential＂ decay is governed by 5t2. This gives a complete and new geometric, intrinsic interpretation of pt（x）.

关键词： transition function estimates levy processes metric measure spaces heat kernel bounds in-finitely divisible distributions self-reciprocal distributions

On-farm Conservation of landraces of Rice (Oryza Sativa l.) through Cultivation in the Kumaun Region of Indian Central Himalaya

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Journal of Mountain Science 2007年第4期4卷 354-360页

作者： R. K. Agnihotri l. M. S. Palni G. B. Pant Institute of Himalayan Environment and Development Kosi - Katarmal Almora 263 643 Uttaranchal India State Biotechnology Programme government of Uttaranchal Biotech Bhavan P. O. Haldi U. S. Nagar 263 146 Uttaranchal India

The Himalayan region is a known hot spot of crop diversity. Traditional varieties (usually called primitive cultivars or landraces), having withstood the rigors of time (including harsh climatic conditions as well as attacks of insects, pests and diseases), can still be found in crop fields in rural parts of Indian Central Himalaya (ICH). These landraces harbor many desired traits from which, for example, varieties that are tolerant/resistant to abiotic/biotic stresses could be developed. In addition to the above benefits, landraces provide a basis for food security and a more varied and interesting diet. Some landraces are also known to be of medicinal value. These, along with some lesser known hill crops, are often referred to by different names such as under exploited crops, crops for marginal lands, poor person crops, and neglected mountain crops. The Himalayan region continues to be a reservoir of a large number of landraces and cultivars whose economic and ecological potential is yet to be fully understood and/or exploited. Indians have had a history of rice cultivation since ancient times. Farmers, including tribals inhabiting the IHR, still cultivate a plethora of landraces of rice and thus directly contribute towardson-farm conservation of valuable germplasm and help in the preservation of crop diversity. The present paper looks at the on-farm conservation of rice germplasm, which is still practised in the Kumaun region of ICH.

关键词： Germplasm Himalaya landraces on-farm conservation rice

Prophylactic effects of asiaticoside-based standardized extract of Centella asiatica(l.) Urban leaves on experimental migraine: Involvement of 5HT1A/1B receptors

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Chinese Journal of Natural Medicines 2015年第4期13卷 274-282页

作者： Vijeta Bobade Subhash l.Bodhankar Urmila Aswar Vishwaraman Mohan Prasad Thakurdesai Department of Pharmacology Poona College of Pharmacy Bharati Vidyapeeth Deemed University Department of Pharmacology Sinhgad Institute of Pharmacy Indus Biotech Private limited 1 Rahul residency Kondhwa Pune-411026 India

The present study aimed at evaluation of prophylactic efficacy and possible mechanisms of asiaticoside （AS） based standardized extract of Centella asiatica （l.） Urban leaves （INDCA） in animal models of migraine. The effects of oral and intranasal （i.n.） pretreatment of INDCA （acute and 7-days subacute） were evaluated against nitroglycerine （NTG, 10 mg·kg^-1, i.p.） and bradykinin （BK, 10 μg, intra-arterial） induced hyperalgesia in rats. Tail flick latencies （from 0 to 240 rain） post-NTG treatment and the number of vocalizations post-BK treatment were recorded as a measure of hyperalgesia. Separate groups of rats for negative （Normal） and positive （sumatriptan, 42 *** ^-1, s.c.） controls were included. The interaction of 1NDCA with selective 5-HT1A, 5-HT1B, and 5-HTI D receptor antagonists （NAN-190, Isamoltane hemifumarate, and BRl-15572 respectively） against NTG-induced hyperalgesia was also evaluated. Acute and sub-acute pre-treatment of INDCA [10 and 30 ***^-1 （oral） and 100 μg/rat （i.n.） showed significant anti-nociception activity, and reversal of the NTG-induced hypera｜gesia and brain 5-HT concentration decline. Oral pre-treatment with INDCA （30 mg·kg ^-1, 7 d） showed significant reduction in the number of vocalization. The anti-nociceptive effects of INDCA were blocked by 5-HTIA and 5-HT1B but not 5-HT1D receptor antagonists. In conclusion, 1NDCA demonstrated promising anti-nociceptive effects in animal models of migraine, probably through 5-HT1A/1B medicated action.

关键词： Centella asiatica (l.) Urban Experimental migraine Anti-nociception Serotonin, 5HTI A and 5HT1B receptors

USING THE SKEW-SYMMETRIC ITERATIVE METHODS FOR SOlUTION OF AN INDEFINITE NONSYMMETRIC lINEAR SYSTEMS

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Journal of Computational Mathematics 2014年第3期32卷 266-271页

作者： B.l. Krukier l.A. Krukier Southern Federal University Computer Center Rostov-on-Don Russia

The concept of the field of value to localize the spectrum of the iteration matrices of the skew-symmetric iterative methods is further exploited. Obtained formulas are derived to relate the fields of values of the original matrix and the iteration matrix. This allows us to determine theoretically that indefinite nonsymmetric linear systems can be solved by this class of iterative methods.

关键词： Skew-symmetric iterative methods Indefinite nonsymmetric linear systems.

呋虫胺和唑虫酰胺在茶叶加工过程中的残留特征及膳食风险评估

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食品科学 2025年第1期46卷 192-199页

作者：李春勇吕莹金静王霞秦曙山西农业大学山西功能农产品检验检测中心山西太原030031

为明确呋虫胺和唑虫酰胺微乳剂在茶叶种植、烘干、浸泡过程中的残留特征,在山东、浙江等10地开展规范农药登记残留田间试验,并进行加工因子校正膳食风险评估模型比较研究。样品经体积分数5%甲酸-乙腈提取、盐析分层、分散固相萃取净化后... 详细信息

为明确呋虫胺和唑虫酰胺微乳剂在茶叶种植、烘干、浸泡过程中的残留特征,在山东、浙江等10地开展规范农药登记残留田间试验,并进行加工因子校正膳食风险评估模型比较研究。样品经体积分数5%甲酸-乙腈提取、盐析分层、分散固相萃取净化后,经超高效液相色谱-串联质谱法检测,外标法定量。结果表明:在0.005~0.500μg/ml范围内,呋虫胺及其代谢物、唑虫酰胺质量浓度与其响应峰面积呈良好线性关系(R^(2)>0.99),在0.05、1.00、20.00、50.00 mg/kg(茶鲜叶、茶干叶),0.05、0.10、5.00 mg/kg(茶汤)添加水平下,呋虫胺及其代谢物1-甲基-3-[(3-四氢呋喃)甲基]脲、1-甲基-3-[(3-四氢呋喃)甲基]二氢胍盐的平均加标回收率为74%~103%,相对标准偏差为1%~9%;唑虫酰胺的平均加标回收率为75%~95%,相对标准偏差为1%~6%,方法定量限均为0.05 mg/kg;20%呋虫胺·唑虫酰胺微乳剂按推荐剂量施药后,呋虫胺(含代谢物)在茶鲜叶中的规范残留试验中值(supervised trials median residue,STMR)经烘干因子校正后与茶干叶中STMR相应的国家估算每日摄入量(national estimated daily intake,NEDI)均为4.08 mg,占每日允许摄入量(allowable daily intake,ADI)的32.4%;唑虫酰胺在茶鲜叶中的STMR经烘干因子校正后的NEDI为0.17581 mg,占ADI的46.5%,茶干叶中STMR对应的NEDI为0.18925 mg,占ADI的50.1%,呋虫胺和唑虫酰胺在不同评估模型下获得的长期膳食暴露风险均低于100%;呋虫胺(含代谢物)经加工因子校正后的国际短期膳食摄入量(international estimation of short-term dietary intake,IESTI)与校正前处于同一风险水平,低于急性参考剂量(acute reference dose,ARfD)(1 mg/kg);唑虫酰胺的IESTI为3.46×10^(-4) mg/kg(采收间隔7 d),低于ARf D(0.01 mg/kg),本研究方法在茶汤中未检测到唑虫酰胺残留,故未得到浸泡因子及相应的IESTI。综上,按推荐剂量在茶树上使用20%呋虫胺·唑虫酰胺微乳剂是安全的,最终残留量对应的长期及急性膳食摄入风险均在可接受范围,利用加工因子校正评估模型更切合实际风险水平。

关键词：呋虫胺唑虫酰胺茶叶加工因子残留特征风险评估

RElIABIlITY ANAlYSIS FOR AN AERO ENGINE TURBINE DISK UNDER lOW CYClE FATIGUE CONDITION

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Acta Metallurgica Sinica(English letters) 2004年第4期17卷 514-520页

作者： C.l.liu Z.Z.lü Y.l.Xu School of Aviation Northwestern Polytechnical University Xi'an 710072 ChinaSchool of Aviation Northwestern Polytechnical University Xi'an 710072 ChinaChina Aviation Research Institute 608 Zhuzhou 412002 China

Reliability analysis methods based on the linear damage accumulation law (lDAl) and load-life interference model are studied in this paper. According to the equal probability rule, the equivalent loads are derived, and the reliability analysis method based on load-life interference model and recurrence formula is constructed. In conjunction with finite element analysis (FEA) program, the reliability of an aero engine turbine disk under low cycle fatigue (lCF) condition has been analyzed. The results show the turbine disk is safety and the above reliability analysis methods are feasible.

关键词： low cycle fatigue life reliability analysis load-life interference model recurrence method aero engine turbine disk

Utilization of α-olefins obtained by pyrolysis of waste high density polyethylene to synthesize α-olefin-succinic-anhydride based cold flow improvers

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燃料化学学报 2009年第3期37卷 302-310页

作者： Norbert MISKOlCZI Richard SAGI lászló BARTHA lívia FORCEK University of Pannonia Chemical Engineering and Process Engineering Institute Department of Hydrocarbon and Coal Processing Egyetem street 10 Veszprém H-8200 HUNGARY

浪费聚合物热分解获得的石蜡富人烃部分的利用的一条新线路被调查。-olefin-succinic-anhydride 基于中介倒点镇静剂添加剂因为柴油被综合，在哪个反应需要的石蜡被废物的热分解获得高密度的聚乙烯(HDPE ) 。石蜡的部分被塑料废物的de... 详细信息

浪费聚合物热分解获得的石蜡富人烃部分的利用的一条新线路被调查。-olefin-succinic-anhydride 基于中介倒点镇静剂添加剂因为柴油被综合，在哪个反应需要的石蜡被废物的热分解获得高密度的聚乙烯(HDPE ) 。石蜡的部分被塑料废物的de聚合在 500 滓鲥?在一个试管反应堆生产???????????????????????禧?????迋????骤??????吗鲥??????禧哉????嫪????滓?????篤?廯??????可??????????????裍??妢???????臙???????蚨?蚨？？

关键词：添加剂石油炼制成份燃料化学高温分解