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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

Sequential Injection Analysis of Ampicillin in Pharmaceuticals by Using Potentiometric Detectors Based on PVC and Sol-Gel Membranes

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American Journal of Analytical Chemistry 2011年第4期2卷 491-499页

作者： Nestor Zarate Alberto N.Araujo M.Conceicao B.S.M.Montenegro Ricardo Perez-olmos Dpto.Quimica Analítica Escuela Universitaria de Ingenieria Tecnica IndustrialUniversidad del Pais VascoPlaza de la Casilla 348012Bilbao REQUIMTE Dpto.de Quimica FisicaFaculdade de FarmaciaUniversidade do PortoRua Anibal Cunha 1644050 PortoPortugal

This work describes the construction and the evaluation of the general performance of new ampicilli-nate-selective electrodes based on manganese (III) tetraphenylporphyrin [Mn(III) TPP-Cl] as ionophore, incorporated in both PVC and sol-gel membranes and directly applied onto a conductive graphite/epoxy resin support. The units were constructed without inner reference solution adopting conventional configuration and in the case of PVC membrane the tubular configuration was also adopted. The good working characteristics of these electrodes, made possible its application to the determination of ampicillin in pharmaceuticals formulations, both in conventional batch analysis and in flow conditions, when the electrodes were coupled to a SIA system. In the last case the potentiometric sensors presented linear response towards ampicillin concentration between 5.0 × 10–4 and 5.0 × 10–2 mol?l–1 with slopes of –57.4 and –63.5 mV?dec–1 for the PVC and sol-gel membranes, respectively. The developed procedures enable mean relative standard deviations better than 3% for all the samples analysed. The obtained results do not statistically differ from those furnished by applying the HPlC reference method.

关键词： Ampicillin SIA Potentiometric Detection Pharmaceutical Formulations

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

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手术部位感染与麻醉的关系

中华麻醉学杂志 2018年第7期38卷 769-774页

作者： Andrea olmos M.D. Adrian W Gelb M.B.Ch.B. F.R.C.P.C. 旧金山加利福尼亚大学、麻醉和围手术期护理科美国加利福尼亚州95531

Surgical site infections (SSIs)are among the most frequently documented healthcare associated infections (HAI)^[1],with an incidence ranging from <1% to 17.8%depending on the reporting country and the procedure^[2].Th... 详细信息

Surgical site infections (SSIs)are among the most frequently documented healthcare associated infections (HAI)^[1],with an incidence ranging from l involving the upper layers of the surgical wound, deep involving deeper layers,or it may involve an organ operated *** often preventable,SSIs continue to represent a significant burden to healthcare systems around the *** are associated with patient morbidity and mortality as well as with staggering medical costs and prolonged hospitalizations^[3].

关键词： Surgical site documented healthcare involving deeper

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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

Hölder,Sobolev,weak-type and BMO estimates in mixed-norm with weights for parabolic equations

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Science China Mathematics 2021年第1期64卷 129-154页

作者： Pablo Raúl Stinga José l.Torrea Department of Mathematics Iowa State UniversityAmesIA50011USA Departamento de Matemáticas Universidad Autónoma de MadridMadrid28049Spain

We prove weighted mixed-norm lqt(W2,px)and lqt(C2,αx)estimates for 10,x∈Rn.x∈Rn,The coefficients a(t)=(aij(t))are just bounded,measurable,symmetric and uniformly ***,we show strong,weak type and BMO-Sobolev estimat... 详细信息

We prove weighted mixed-norm lqt(W2,px)and lqt(C2,αx)estimates for 1l∞t(lpx)−BMOt(W2,px)and l∞t(Cαx)−BMOt(C2,xx),and *** formulas for derivatives,for the solutions u=u(t,x)to parabolic equations of the form∂tu−aij(t)∂iju+u=f,t∈,x∈n and for the Cauchy problem{∂tv−aij(t)∂ijv+v=fv(0,x)forfort>0,x∈Rn.x∈Rn,The coefficients a(t)=(aij(t))are just bounded,measurable,symmetric and uniformly ***,we show strong,weak type and BMO-Sobolev estimates with parabolic Muckenhoupt *** is quite remarkable that most of our results are new even for the classical heat equation∂tu−Δu+u=f.

关键词： Calderón-Zygmund parabolic singular integrals weak type and BMO estimates representation formulas parabolic equations mixed-norm Sobolev and Schauder estimates