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Estimation of the b.llistic 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 Prob.ems 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 b.en ob.ained(261.5±5.0and 246.4±6.7kJ/mol for crystalline 3,4-and 3,5-dinitro-1-(trinitromethyl)-1H-pyrazoles,respectively).The b.llistic effectiveness of these potential oxidizers in composite solid propellants was studied.It is shown that these two oxidizers may b. successfully applied in metal-free compositions or with a small content of metal.For the b.ttom stage 3,4-dinitro-1-(trinitromethyl)-1H-pyrazole is a b.t b.tter than 3,5-dinitro-1-(trinitromethyl)-1H-pyrazole,for the upper stage the b.th oxidizers show the equal b.llistic parameters.These oxidizers allow to create metal-free solid composite propellants with the b.nder 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 b.llistic effectiveness

Energetic Opportunities of Solid Composite Propellants Containing Some Hypothetic Furazano-[3,4-d]-pyridazine-b.sed 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 Prob.ems 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-b.sed derivatives as main compounds in solid composite propellants have b.en investigated.It was shown that the use of some furazano-[3,4-d]-pyridazine-b.sed derivatives as main compounds in solid composite propellants can considerab.y increase b.llistic parameters compared with HMX if the compounds under consideration contain difluoramine groups.And the use of the compounds under consideration may b. successful only in the presence of an active b.nder and 10%-30% of AP or ADN as additional oxidizers.

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

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 Prob.ems 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 b. evaluation of the specific impulse values of these components serving as an only component in the formulation.Such an approach may turn the researcher to a wrong conclusion.One has to compare compound′s potential in formulations close to real,e.***.at least with necessary amount of b.nders.Dependences of specific impulse upon element content of highenthalpy CHNO oxidizer,its enthalpy of formation,and kind of b.nder have b.en found.

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

3,6-b.s(2,2,2-trinitroethylnitramino)-1,2,4,5-tetrazine.Structure and energy ab.lities 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 Prob.ems 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-b.s(2,2,2-trinitroethylnitramino)-1,2,4,5-tetrazine(Nb.AT),first ob.ained b. the authors in 2020.Nb.AT 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 Nb.AT and its unnitrated analogue b.AT were calculated,and their comparative analysis was carried out.The enthalpy of formation of Nb.AT molecules was calculated b. quantum-chemical methods using Gaussian 09,and the enthalpy of formation of Nb.AT in the solid phase(618 kJ/mol)was estimated.The energy capab.lities of Nb.AT as an oxidizer of solid composite propellants are estimated.It is shown that in metal-free compositions Nb.AT is significantly superior to ammonium perchlorate(AP),dinitramide ammonium salt(ADN),HMX,b.AT at all stages of rocket systems,and is comparab.e 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-b.s(2,2,2-trinitroethylnitramino)-1,2,4,5-tetrazine Crystal structure Energetic ab.lity

Classic axon guidance molecules control correct nerve b.idge tissue formation and precise axon regeneration

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Neural Regeneration Research 2020年第1期15卷 6-9页

作者： Xin-Peng Dun david b.arkinson Faculty of Medicine and Dentistry Plymouth UniversityPlymouthDevonUK The Co-Innovation Center of Neuroregeneration Nantong UniversityNantongJiangsu ProvinceChina School of Pharmacy Hubei University of Science and TechnologyXianningHubei ProvinceChina

The peripheral nervous system has an astonishing ab.lity to regenerate following a compression or crush injury;however,the potential for full repair following a transection injury is much less.Currently,the major clinical challenge for peripheral nerve repair come from long gaps b.tween the proximal and distal nerve stumps,which prevent regenerating axons reaching the distal nerve.Precise axon targeting during nervous system development is controlled b. families of axon guidance molecules including Netrins,Slits,Ephrins and Semaphorins.Several recent studies have indicated key roles of Netrin1,Slit3 and Ephrinb. signalling in controlling the formation of new nerve b.idge tissue and precise axon regeneration after peripheral nerve transection injury.Inside the nerve b.idge,nerve fib.ob.asts express Ephrinb. while migrating Schwann cells express the receptor Ephb..Ephrinb./Ephb. signalling b.tween nerve fib.ob.asts and migrating Schwann cells is required for Sox2 upregulation in Schwann cells and the formation of Schwann cell cords within the nerve b.idge to allow directional axon growth to the distal nerve stump.Macrophages in the outermost layer of the nerve b.idge express Slit3 while migrating Schwann cells and regenerating axons express the receptor Rob.1;within Schwann cells,Rob.1 expression is also Sox2-dependent.Slit3/Rob.1 signalling is required to keep migrating Schwann cells and regenerating axons inside the nerve b.idge.In addition to the Slit3/Rob.1 signalling system,migrating Schwann cells also express Netrin1 and regenerating axons express the DCC receptor.It appears that migrating Schwann cells could also use Netrin1 as a guidance cue to direct regenerating axons across the peripheral nerve gap.Engineered neural tissues have b.en suggested as promising alternatives for the repair of large peripheral nerve gaps.Therefore,understanding the function of classic axon guidance molecules in nerve b.idge formation and their roles in axon regeneration could b. highly b.neficial in developing engineered neural

关键词： axonal guidance Ephrinb. nerve b.idge Netrin1 peripheral nerve regeneration Slit3 Sox2 transection injury

Three-Dimensional Sub.100 nm Super-Resolution Imaging of b.ological Samples Using a Phase Ramp in the Ob.ective Pupil

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Nano Research 2011年第6期4卷 589-598页

作者： david b.ddeley Mark b. Cannell Christian Soeller Department of Physiology University of Auckland Private Bag 92019 Auckland 1142 New Zealand

本地化显微镜学由测量单个分子的位置比 30 nm 更好与侧面的分辨率获得光图象克服衍射限制。单个分子本地化显微镜学原来仅仅在二种尺寸被表明，但是最近被扩大了到三种尺寸。这里，我们开发一条新途径到三维(3D ) 由一台荧光显微镜的... 详细信息

本地化显微镜学由测量单个分子的位置比 30 nm 更好与侧面的分辨率获得光图象克服衍射限制。单个分子本地化显微镜学原来仅仅在二种尺寸被表明，但是最近被扩大了到三种尺寸。这里，我们开发一条新途径到三维(3D ) 由一台荧光显微镜的点传播功能(PSF ) 的工程的本地化显微镜学。由介绍在客观学生飞机的二一半之间的一个线性阶段坡度， PSF 被分成位置取决于其亲戚的二片侧面的脑叶散焦。计算建议从小忍耐导致用漂流玻璃做的常规幻灯片的并行的阶段坡度将是足够的产生二脑叶的 PSF。我们表明占据与快为 3D 本地化评价适合算法的一篇小说相结合的半客观的孔的一个合适选择的显微镜幻灯片的那插入在所有三种尺寸在 100 nm 下面与详细分辨率允许 nanoscopic 成像很好(在 x 的 20 ， 16 ，和 42 nm 的标准差， y ，和 z 方向，分别地)。途径的用途被成像在与常规近红外线的 fluorochromes 被染色的心肌房间看微导管的复杂 3D 分发。直接光安装，最小的硬件要求和大轴的本地化范围为许多 nanoscopic 成像应用程序使这条途径合适。

关键词：纳米光学三维分布成像超分辨率生物样品荧光显微镜学生图像位置

Olfactory outcomes in the management of aspirin exacerb.ted respiratory disease related chronic rhinosinusitis

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World Journal of Otorhinolaryngology-Head and Neck Surgery 2020年第4期6卷 207-213页

作者： Daniel b.Spielman Jonathan Overdevest david A.Gudis Departm ent of Otolaryngology-Head and Neck Surgery Columbia University Medical CenterNew YorkNY10032USA

Patients with aspirin exacerb.ted respiratory disease(AERD)experience a severe and recalcitrant form of chronic rhinosinusitis with nasal polyposis(CRSwNP)and asthma,which are exacerb.ted b. aspirin/NSAID ingestion.As compared with aspirin-tolerant CRSwNP,patients with AERD experience more severe olfactory dysfunction,which is one of the key contrib.tors to the ob.erved decrease in quality of life(QOL)in this disease.The ob.ective of this paper is to review the pub.ished olfactory outcomes ob.erved with various treatment modalities.

关键词： Aspirin exacerb.ted respiratory disease AERD Samter’s Triad Olfaction hyposmia Endoscopic sinus surgery Aspirin desensitization NSAID

Simulation training in endoscopic skull b.se surgery: A scoping review

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World Journal of Otorhinolaryngology-Head and Neck Surgery 2022年第1期8卷 73-81页

作者： Joel James Alexandria L.I race david A.Gudis Jonathan b.Overdevest City University of New York School of Medicine New YorkNew YorkUSA Department of Otolaryngology-Head and Neck Surgery Columbia University Vagelos College of Physicians and SurgeonsColumbia University Irving Medical CenterNew York-Presbyterian HospitalNew YorkNew YorkUSA

Ob.ective:Proficiency in endoscopic endonasal skull b.se surgery requires b.th sub.tantial b.seline training and progressive lifelong learning.Endoscopic simulation models continue to evolve in an effort to optimize trainee education and preoperative preparation and improve surgical outcomes.The current scoping review systematically reviews all availab.e literature and synthesizes the current paradigms of simulation models for endoscopic skull b.se surgery training and skill enhancement.Methods:In accordance with Preferred Reporting Items for Systemic Review and Meta-Analyses guidelines,we systematically searched Pub.ed,Emb.se,CINAHL,and Cochrane datab.ses.Studies were categorized according to the type of simulation models investigated.Results:We identified 238 unique references,with 55 studies ultimately meeting inclusion criteria.Of these,19 studies describ.d cadaveric dissection models,17 discussed three-dimensional(3D)printed models,14 examined virtual surgical planning and augmented reality-b.sed models,and five 5 articles describ.d task trainers.Conclusions:There are a wide variety of simulation models for endoscopic skull b.se surgery,including high-fidelity cadaveric,virtual reality,and 3D-printed models.These models are an asset for trainee development and preoperative surgical preparation.

关键词： resident education skull b.se surgery surgical simulation training virtual reality virtual surgical planning

A contemporary evidence b.sis for neoadjuvant chemotherapy in upfront resectab.e pancreatic adenocarcinoma:a systematic review of the literature

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Journal of Pancreatology 2020年第1期3卷 12-20页

作者： Stonko david P. He Jin Zheng Lei b.air Alex b. The Pancreatic Cancer Precision Medicine Center of Excellence Program Johns Hopkins University School of MedicineBaltimoreMDUSA Section of Hepatob.liary and Pancreatic Surgery Division of Surgical OncologyJohns Hopkins HospitalBaltimoreMDUSA Division of Oncology Johns Hopkins University School of MedicineBaltimoreMDUSA

Pancreatic ductal adenocarcinoma(PDAC)is an aggressive cancer with poor survival.Local control through surgical resection paired with radiotherapy and chemotherapy comprise the primary tenets of treatment.Deb.te exists regarding the timing of treatment and ordering of systemic therapy and resection in the management of early stage disease.The goal of this study was to review the literature and describ. the contemporary evidence b.sis for the role of neoadjuvant therapy(NAT)in the setting of upfront resectab.e(UP-R)PDAC.Five datab.ses were searched in parallel to identify relevant original articles investigating neoadjuvant therapy where at least 1 study arm contained UP-R PDAC;studies with only b.rderline resectab.e or locally advanced disease were excluded.Due to the diversity in NAT regimens and study design b.tween trials,qualitative analyses were performed to investigate patient selection,impact on perioperative and survival outcomes,safety,and cost effectiveness.Thirty-five studies met inclusion criteria,of which 24 unique trials are discussed here in detail.These studies included those trials using single agents as well as more recent trials comparing modern multiagent therapies,and several large datab.se analyses.Overall the data suggest that NAT is safe,may confer survival b.nefit for appropriately selected patients,is cost effective,and is an appropriate approach for UP-R PDAC.Nevertheless,the risk for disease progression during upfront medical therapy,requires appropriate patient identification and close monitoring,and emphasizes the need for further discovery of more effective chemotherapeutics,useful b.omarkers or molecular profiles,and additional prospective comparative studies.

关键词： Neoadjuvant therapy Pancreatic ductal adenocarcinoma Pancreatic neoplasms Preoperative chemotherapy Resectab.e pancreatic cancer Upfront resectab.e