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Dependence of Specific Impulse of Metal-free Formulations on CHNO-oxidizer′s Element Content and Enthalpy of Formation

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火炸药学报 2015年第4期38卷 1-4页

作者： David B.lempert Institute of Problems of Chemical Physics of Russian Academy of Sciences Semenov av.1ChernogolovkaMoscow Region 142432 Russia

It is shown that it is not correct to estimate energetic characteristics of different compounds of solid composite propellants by evaluation of the specific impulse values of these components serving as an only component in the *** an approach may turn the researcher to a wrong *** has to compare compound′s potential in formulations close to real,*** least with necessary amount of *** of specific impulse upon element content of highenthalpy CHNO oxidizer,its enthalpy of formation,and kind of binder have been found.

关键词： solid composite propellants high-enthalpy oxidizer energetic parameters estimation specific impulse

3,6-bis(2,2,2-trinitroethylnitramino)-1,2,4,*** and energy abilities as a component of solid composite propellants

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Defence technology（防务技术） 2022年第7期18卷 1148-1155页

作者： Anatoly G.Korepin Natalia M.Glushakova David B.lempert Anatoly I.Kazakov Gennady V.Shilov Denis V.Korchagin Vadim M.Volokhov Elena S.Amosova Sergey M.Aldoshin Institute of Problems of Chemical Physics Ac.Semenov Avenue 1Chernogolovka142432Russian Federation

the work addresses to the study of the molecular and crystal structure and properties of a new energyintensive compound 3,6-bis(2,2,2-trinitroethylnitramino)-1,2,4,5-tetrazine(NBtAt),first obtained by the authors in *** compound crystallizes in the monoclinic system,space group P2(1)/n,density at room temperature 1.939 g/cm^(3).the energies of crystal packing and pairwise intermolecular interactions in NBtAt and its unnitrated analogue BtAt were calculated,and their comparative analysis was carried *** enthalpy of formation of NBtAt molecules was calculated by quantum-chemical methods using Gaussian 09,and the enthalpy of formation of NBtAt in the solid phase(618 kJ/mol)was *** energy capabilities of NBtAt as an oxidizer of solid composite propellants are *** is shown that in metal-free compositions NBtAt is significantly superior to ammonium perchlorate(AP),dinitramide ammonium salt(ADN),HMX,BtAt at all stages of rocket systems,and is comparable to the superdense CL-20 yielding to the latter at the lower stages and slightly winning at the upper stages.

关键词： Nitrogen heterocycles Quantum chemistry Enthalpy of formation 3,6-bis(2,2,2-trinitroethylnitramino)-1,2,4,5-tetrazine Crystal structure Energetic ability

Energetic Abilities of Solid Composite Propellants Based on 3,4,5-trinitropyrazole and Ammonium Dinitramide

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火炸药学报 2016年第3期39卷 17-20页

作者： lempert David B. CHUKANOV Nikita SHU Yuan-jie Institute of Problems of Chemical Physics Russian Academy of SciencesMoscow 142432Russia Xi′an Modern Chemistry Research Institute Xi′an 710065China

the investigation aims at the expansion of the basis of formulations of solid composite propellants by introducing new compositions with lower sensitivity to mechanic impact and improved thermal *** formulations based on trinitropyrazole(tNP)contains a binder(a hydrocarbon or active one),aluminum and inorganic oxidizer *** results show that a binary formulation tNP+active binder(18%-19%)(volume fraction)with no metal is well designed which would achieve high specific impulse(at Pc∶Pa=40∶1)of 248s,high density of 1.80g/cm3 and combustion temperature tcabout 3 *** terms of energy,metal-free compositions with tNP lose a bit to those with HMX,only if HMX fraction in formulation is higher than 45%-50%.

关键词： solid composite propellants specific impulse 3,4,5-trinitropyrazole tNP binder ammonium dinitramide ADN

Estimation of the Ballistic Effectiveness of 3,4-and 3,5-Dinitro-1-(trinitromethyl)-1H-Pyrazoles as Oxidizers for Composite Solid Propellants

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火炸药学报 2016年第2期39卷 16-21页

作者： lempert David B. DALINGER Igor L. SHU Yuan-jie KAZAKOV Anatolii I. SHEREMEtEV Aleksei B. Institute of Problems of Chemical Physics Russian Academy of Sciences(IPCP RAS) Moscow 142432 Russia Zelinsky Institute of Organic Chemistry Russian Academy of Sciences Moscow 119991 Russia Xi'an Modern Chemistry Research Institute Xi'an 710065 China

the experimental values of the enthalpy of formation of two isomeric 3,4-and 3,5-dinitro-1-(trinitromethyl)-1H-pyrazoles have been obtained(261.5±5.0and 246.4±6.7kJ/mol for crystalline 3,4-and 3,5-dinitro-1-(trinitromethyl)-1H-pyrazoles,respectively).the ballistic effectiveness of these potential oxidizers in composite solid propellants was *** is shown that these two oxidizers may be successfully applied in metal-free compositions or with a small content of *** the bottom stage 3,4-dinitro-1-(trinitromethyl)-1H-pyrazole is a bit better than 3,5-dinitro-1-(trinitromethyl)-1H-pyrazole,for the upper stage the both oxidizers show the equal ballistic *** oxidizers allow to create metal-free solid composite propellants with the binder percentage not lower than 19%(volume fraction),with I3spequal to 256.5-257.0sat density equal to 1.72-1.74g/cm^3.

关键词： composite solid propellants high-enthalpy oxidizer energetic parameters estimation specific impulse ballistic effectiveness

Energetic Opportunities of Solid Composite Propellants Containing Some Hypothetic Furazano-[3,4-d]-pyridazine-based Derivatives

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火炸药学报 2016年第5期39卷 28-34页

作者： lempert David B. DOROFEENKO Ekaterina M. SHU Yuan-jie JIANG Wei-dong WU Zong-kai WANG Ke LIU Xiao-qiang Institute of Problems of Chemical Physics Russian.Academy of Sciences(IPCP RAS)Moscow 142432 Russia Xi'an Modern Chemistry Research Institute Xi'an 710065China School of Chemistry and Environmental Engineering Sichuan.University of Science and EngineeringZigong Sichuan.643000China

Six furazano-[3,4-d]-pyridazine-based derivatives as main compounds in solid composite propellants have been *** was shown that the use of some furazano-[3,4-d]-pyridazine-based derivatives as main compounds in solid composite propellants can considerably increase ballistic parameters compared with HMX if the compounds under consideration contain difluoramine *** the use of the compounds under consideration may be successful only in the presence of an active binder and 10%-30% of AP or ADN as additional oxidizers.

关键词： solid composite propellant furazano-[3,4-d]-pyridazine-based derivative energetic specific impulse

Prediction of the Enhanced Out-of-Plane thermal Conductivity of Carbon Fiber Composites Produced by VARtM

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Open Journal of Composite Materials 2016年第4期6卷 100-111页

作者： Jens Schuster Martin Schütz Johannes Lutz Laura lempert Institut für Kunststofftechnik Westpfalz University of Applied Sciences Kaiserslautern Pirmasens Germany

the thermal conductivity of epoxy resin can be increased by a factor of eight to ten by loading with highly conductive particles. However, higher loadings increase the viscosity of the resin and hamper its use for liquid composite molding processes. thus, the enhancement of the out-of-plane thermal conductivity of carbon composites manufactured by VARtM and accomplished by matrix filling is limited to about 250%. In order to derive higher increases in out-of-plane thermal conductivity, additional measures have to be taken. these consist of introducing thermally conductive fibers in out-of-plane direction of the preform using a 3D-weaving process. Measured out-of-plane thermal conductivities of 3D-woven fabric composites are significantly increased compared to a typical laminated composite. It has been shown that if introducing highly conductive z-fibers, the use of a particle filled resin is not necessary and furthermore should be avoided due to the manufacturing problems mentioned above. An existing analytical model was altered to predict the effective thermal conductivity as a function of the composite material properties such as the thermal conductivities and volume contents of fibers in in-plane and out-of-plane directions, the thermal conductivity of the loaded resin, the grid-density of the out- of-plane fibers, and material properties of the contacting material. the predicted results are compared with measured data of manufactured samples.

关键词： thermal Conductivity Vacuum Assisted Resin transfer Molding (VARtM) 3D-Weaving Modeling Woven Fabric Composites

Dizziness : a practical approach to diagnosis and management

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2007年

作者： Adolfo M. Bronstein thomas lempert.

来源：畅想之星图书光盘版（南... 评论

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畅想之星图书光盘版（南通市图书馆镜像）

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新证据学:对证明过程的分析

法律方法 2022年第1期28卷 116-141页

作者： [美]理查德·伦伯特成小爱(译) 密歇根大学法学院中国政法大学证据科学研究院

一、证据学:从规则到证明十七年前,当我开始教授证据法的时候,这块领域是停滞不前的。对于普通法上伟大的系统主义者——威格摩尔(Wigmore)、马奎尔(Maguire)、麦考密克(McCormick)、摩根(Morgan)以及他们的同僚来说,即使他们没有全部离... 详细信息

一、证据学:从规则到证明十七年前,当我开始教授证据法的时候,这块领域是停滞不前的。对于普通法上伟大的系统主义者——威格摩尔(Wigmore)、马奎尔(Maguire)、麦考密克(McCormick)、摩根(Morgan)以及他们的同僚来说,即使他们没有全部离去,他们的工作也基本上已经完成了。不但大多数所谓的证据学的东西几乎不值一读(其实,大多数时候法学许多领域的研究可以说都是如此),而且几乎没有学者会定期就证据问题进行学术写作(如果不算学生作业的话)。

关键词：证据学普通法证据法麦考密克学术写作学生作业威格摩尔法学

前庭性偏头痛诊断标准(更新):Bárány协会及国际头痛协会共识文件

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神经损伤与功能重建 2022年第10期17卷 559-562页

作者：邢玥(译) 凌霞(译) 王钰茹(译) 荣良群(审校) 杨旭(审校) thomas lempert Jes Olesen Joseph Furman John Waterston Barry Seemungal John Carey Alexander Bisdorff Maurizio Versino Stefan Evers Amir Kheradmand David Newman-toker 航天中心医院(北京大学航天临床医学院)神经内科徐州医科大学第二附属医院神经内科德国柏林Schlosspark-Klinik医院神经病学科丹麦哥本哈根大学头痛中心和神经病学系美国宾夕法尼亚州匹兹堡大学耳鼻喉科学系及神经病学系澳大利亚墨尔本阿尔弗雷德医院莫纳什大学神经科学系英国伦敦Charing Cross医院临床神经科学系美国马里兰州巴尔的摩约翰·霍普金斯大学医学院耳鼻喉头颈外科学系卢森堡阿尔泽特河畔埃施医学中心神经病学系意大利瓦雷泽Ospedale di Circolo ASSt Sette Laghi医院神经病学科和卒中单元意大利瓦雷泽英苏布里亚大学德国Coppenbrügge Krankenhaus Lindenbrunn医院神经病学科美国马里兰州巴尔的摩约翰·霍普金斯大学医学院神经病学系

本文介绍了由Bárány协会国际前庭疾病分类(International Classification of Vestibular Disorders,ICVD)委员会和国际头痛协会(International Headache Society,IHS)偏头痛分类小组共同制定的前庭性偏头痛(vestibular migraine,VM)的诊断标准。本文包含了部分文献更新,原2012版本的诊断标准仍然不变。诊断标准包括VM和很可能的VM两类。根据常规的IHS流程,VM作为一个新的疾病类型,将首先被纳入第三版国际头痛分类(International Classification of Headache Disorders,ICHD)的附录。随着研究证据的进一步增加,很可能的VM也有待被纳入到未来的ICHD版本中。VM的诊断包括:反复发作的前庭症状、偏头痛的病史、前庭症状与偏头痛症状存在时间关联,且排除其他可能导致前庭症状发生的相关病因。符合VM诊断的症状包括多种类型:如眩晕、头动诱发的头晕伴恶心等,但临床上,上述症状的严重程度须为中度或重度,急性发作的持续时间需在5 min~72 h。

关键词：偏头痛眩晕头晕前庭诊断标准 Bárány协会国际头痛协会