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Defence Technology（防务技术） 2023年第9期27卷 184-192页

作者： cheng-chuang Li Hao Gu Jie Tang Guo-jie Zhang guang-bin cheng Hong-wei Yang School of Chemistry and Chemical Engineering Nanjing University of Science and TechnologyNanjing210094China

In recent years,the introduction of fused rings own high density and low sensitivity has promoted the development of energetic ***,the development of energetic compounds containing fused and bridged rings by introducing multiple nitrogen heterocycles at different sites of fused rings is still difficult to progress,which seriously limits the emergence of advanced energetic *** this study,a series of energetic materials choosing different nitrogen rich heterocycles at the vacancies of the fused ring,i.e.,neutral compound 5,6 and their ionic derivatives(compounds 7-12)were designed and *** 5 and 6 were further confirmed by single crystal X-ray diffraction,while the crystal analysis and theoretical calculations were carried out to explore the relationship between crystal structure and physicochemical *** of the newly synthesized compounds(5-12)are insensitive to mechanical stimulation(IS>40 J;FS≥342 N)and they own the high detonation velocity(D:8322-9075 m/s).Notably,hydrazine salt 11 own the higher detonation velocity(9075 m/s)and powder density(1.83 g/cm^(3)),but exhibits lower sensitivity(IS>40 J)than the classical energetic compound RDX(8795 m/s,1.80 g/cm^(3),7.5 J).It is obvious that the combination of 5,6-fused triazolo-triazine and nitropyrazole-tetrazole may be a new energetic skeleton for synthesising the heterocyclic compounds with balanced energy-stability.

关键词： Fused and bridged rings Energetic skeleton Balanced energy-stability Energetic materials

Divalent nitrogen-rich cationic salts with great gas production capacities

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Defence Technology（防务技术） 2023年第4期22卷 54-68页

作者： Hao Gu cheng-chuang Li Chang-hao Dai Dong-xu Chen Hong-wei Yang guang-bin cheng School of Chemistry and Chemical Engineering Nanjing University of Science and TechnologyXiaolingwei 200Nanjing210094PR China

Monocyclic nitrogen-rich 3-(aminomethyl)-4,5-diamine-1,2,4-triazole(1)and fused cyclic 3,7-diamine-6-(aminomethyl)-[1,2,4]triazolo[4,3-b][1,2,4]triazole(9)were synthesized through the convenient cyclization reaction from the readily available *** energetic salts with high nitrogen content were proved to be rare examples of divalent monocyclic/fused cyclic cationic salts according to the single crystal *** structure of intermediate B was also identified and verified by its trivalent cation crystal 17.5H_2O *** compounds 2-8 and 10-17 were fully characterized by NMR spectroscopy,infrared spectroscopy,differential scanning calorimetry,elemental *** energetic salts exhibit good thermal stability with decomposition temperatures ranged from 182℃to 245℃.The sensitivity of compounds 2,6,10 and 14 is similar or superior to that of RDX while the others were much more insensitive to mechanical ***,detonation velocity of 10(8843 m/s)surpass that of RDX(D=8795 m/s).Considering the high gas production volume(≥808 L/kg)of 2,4,10and 12,constant-volume combustion experiments were conduct to evaluate their gas production capacities *** compounds possess much higher maximum gas-production pressures(P_(max):7.88-10.08 MPa)than the commonly used reagent guanidine nitrate(GN:P_(max)=4.20 MPa),which indicate their strong gas production capacity.

关键词： Fused cyclic compound Triazole Divalent cation Gas production Energetic materials

The integration of dinitropyrazole and 1,3,4-oxadiazole:A novel hybrid heterocyclic skeleton for balancing energy and stability

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Defence Technology（防务技术） 2023年第6期24卷 122-128页

作者： Xiao-xiao Zheng Ting-ou Yan Lei Qian Hong-wei Yang guang-bin cheng School of Chemistry and Chemical Engineering Nanjing University of Science and TechnologyNanjing210094China

In this study,a new energetic hybrid skeleton was constructed through the integration of nitropyrazole and 1,3,4-oxadiazole skeletons in a ***,the energetic precursor(2),the azo-bridged compound(3),the neutral nitramine(4)and the corresponding energetic salts(5-7)were *** physicochemical and energetic properties we re experimentally and theo retically *** the developed compounds,the azo-bridged compound(3)and dihydroxylammoinium(6)display high detonation performances(3,D_(v)=8904 m/s,P=34.47 GPa;6,D_(v)=9025 m/s,P=34.66 GPa),moderate sensitivities(3,IS=16 J,FS=120 N;6,IS=20 J,FS=312 N)and good densities(3,1.87 g/cm^(3);6,1.81 g/cm^(3)),which indicates that they have the potential to replace the traditional high-energy explosive *** results show that the integration of different energetic skeletons can achieve a good balance between energy and sensitivity.

关键词： Heterocycle Azo-bridged Hybrid skeletons Energetic materials

Theoretical study of BTF/TNA cocrystal: Effects of hydrostatic pressure and temperature

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Defence Technology（防务技术） 2015年第2期11卷 132-139页

作者： Peng-yuan CHEN Lin ZHANG Shun-guan ZHU guang-bin cheng School of Chemical Engineering Nanjing University of Science and Technology

Cocrystallization is a promising technique for the design and preparation of new explosives,and the stability of cocrystal is highly concerned by the *** order to make a better understanding of the behavior of cocrystal under the extreme conditions,DFT(density functional theory) calculation is performed to investigate the effect of hydrostatic pressure on geometrical and electronic structures of the cocrystal BTF(benzotrifuroxan)/TNA(2,4,6-trinitroaniline).When the hydrostatic pressure is applied,the lattice constants,volume,density and total energy change gradually except at the pressures of 40 GPa and 79e83 *** is noteworthy that new chemical bonds form when the pressure is up to83 *** band gap of the cocrystal becomes smaller when the pressure is applied,and finally the cocrystal shows a characteristic of *** mechanical property of cocrystal is calculated by MD(molecular dynamics) *** results show that the cocrystal has a better ductibility at low temperature,and has the best tenacity at 295 K.

关键词：静水压力共结晶 BTF TNA 密度泛函理论温度模拟计算分子动力学

Giant molecules:where chemistry,physics,and bio-science meet

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Science China Chemistry 2017年第3期60卷 338-352页

作者： guang-Zhong Yin Wen-bin Zhang Stephen Z.D. cheng Key Laboratory of Polymer Chemistry & Physics of Ministry of Education Center for Soft Matter Science and EngineeringCollege of Chemistry and Molecular EngineeringPeking University College of Polymer Science and Polymer Engineering The University of Akron

This feature article focuses on the recent development of giant molecules,which has emerged at the interface among chemistry,physics,and *** molecular designs are inspired by natural polymers like proteins and are modularly constructed from molecular nanoparticle building blocks via sequential "click" *** important molecular parameters such as topology,composition,and molecular weight can be precisely *** hierarchical assembly reveals many features reminiscent of both small molecules and proteins yet unusual for conventional synthetic *** features are summarized and compared along with synthetic polymers and ***,examples are given in each category of giant molecules to illustrate the characteristics of their hierarchical assembly across different length,time and energy *** idea of "artificial domain" is presented in analogy to the structural domains in *** doing so,we aim to develop a rational and modular approach toward functional *** factors that dominate the materials functions are discussed with respect to the precision and dynamics of the *** complexity of structure-function relationship is acknowledged,which suggests that there is still a long way to go toward the convergence of synthetic polymers and biopolymers.

关键词： giant molecules molecular nanoparticles protein protein engineering domains

Molecular simulation study of the microstructures and properties of pyridinium ionic liquid[HPy][BF_(4)]mixed with acetonitrile

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原子与分子物理学报 2025年第4期42卷 27-32页

作者： XU Jian-Qiang MA Zhao-Peng cheng Si LIU Zhi-Cong ZHU guang-Lai Department of Physics School of Physics and Electronic InformationAnhui Normal UniversityWuhu 241002China

The microstructures and thermodynamic properties of mixed systems comprising pyridinium ionic liquid[HPy][BF_(4)]and acetonitrile at different mole fractions were studied using molecular dynamics simulation in this *** following properties were determined:density,self-diffusion coefficient,excess molar volume,and radial distribution *** results show that with an increase in the mole fraction of[HPy][BF_(4)],the self-diffusion coefficient ***,the excess molar volume initially decreases,reaches a minimum,and then *** rules of radial distribution functions(RDFs)of characteristic atoms are *** increasing the mole fraction of[HPy][BF_(4)],the first peak of the RDFs of HA1-F decreases,while that of CT6-CT6 rises at first and then *** indicates that the solvent molecules affect the polar and non-polar regions of[HPy][BF_(4)]differently.

关键词： Pyridinium ionic liquids Thermodynamic properties Molecular dynamics simulation Radial distribution functions

Resistance of Cement-based Grouting Materials with Nano-SiO2 Emulsion to Chloride Ion Penetration

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Journal of Wuhan University of Technology(Materials Science) 2025年第1期 114-119页

作者：黎水平 cheng Jian WEI Chao YUAN bin YU chengxiao College of Architectural Science and Engineering Yangzhou University

The chloride penetration resistance of cement-based grout materials was improved by nano-silica *** of mixtures containing different nano-silica particles or emulsions were exposed in sodium chloride solutions of specific concentrations with different test *** properties of the mixes were assessed in terms of weight loss and compressive strength.X-ray diffraction （XRD） and scanning electron microscopy （SEM） of mixes were performed to analysis the phase evolution and *** results demonstrated that the introduction of nano-SiO2emulsion significantly decreased the compressive strength loss and calcium hydroxide （CH） crystal content of hydration production,and then enhanced the resistance of cement-based grouting materials to chloride ion *** improvement derives from the filling and pozzolanic effects of nano-SiO2particles,which were incorporated via an emulsion and attributed to a well dispersion in grouting matrix.

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Mutual detoxification of mercury and selenium in unicellular Tetrahymena

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Journal of Environmental Sciences 2018年第6期30卷 143-150页

作者： cheng-bin Liu Li Zhang Qi Wu guang-bo Qu Yong-guang Yin Li-gang Hu Jian-bo Shi Gui-bin Jiang State Key Laboratory of Environmental Chemistry and Ecotoxicology Research Center for Eco-Environmental Sciences Chinese Academy of Sciences College of Resources and Environment University of Chinese Academy of Sciences Institute of Environment and Health Jianghan University

Selenium（Se） is commonly recognized as a protective element with an antagonistic effect against mercury（Hg） toxicity. However, the mechanisms of this Hg–Se antagonism are complex and remain controversial. To gain insight into the Hg–Se antagonism, a type of unicellular eukaryotic protozoa（Tetrahymena malaccensis, T. malaccensis） was selected and individually or jointly exposed to two Hg and three Se species. We found that Se species showed different toxic effects on the proliferation of T. malaccensis with the toxicity following the order：selenite（Se（IV））〉 selenomethionine（SeMeth）〉 selenate（Se（VI））. The Hg–Se antagonism in Tetrahymena was observed because the joint toxicity significantly decreased under co-exposure to highly toxic dosages of Hg and Se versus individual toxicity. Unlike Se（IV） and Se（VI）, non-toxic dosage of SeM eth significantly decreased the Hg toxicity, revealing the influence of the Se species and dosages on the Hg–Se antagonism. Unexpectedly, inorganic divalent Hg（Hg2＋） and monomethylmercury（MeHg） also displayed detoxification towards extremely highly toxic dosages of Se, although their detoxifying efficiency was discrepant. These results suggested mutual Hg–Se detoxification in T. malaccensis, which was highly dependent on the dosages and species of both elements. As compared to other species, SeM eth and MeHg promoted the Hg–Se joint effects to a higher degree. Additionally, the Hg contents decreased for all the Hg–Se co-exposed groups, revealing a sequestering effect of Se towards Hg in T. malaccensis.

关键词： Mercury Selenium Antagonism Mutual detoxification Species

Relationship between longitudinal changes in lipid composition and ischemic stroke among hypertensive patients

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World Journal of Clinical Cases 2025年第4期13卷 18-27页

作者： cheng-cheng Wei Yu-Qing Huang cheng-Hong Yu Department of Cardiology Tongxiang First People's HospitalTongxiang 314500Zhejiang ProvinceChina Department of Cardiology Guangdong Cardiovascular InstituteGuangzhou 510080Guangdong ProvinceChina

BACKGROUND Dyslipidemia was strongly linked to stroke,however the relationship between dyslipidemia and its components and ischemic stroke remained *** To investigate the link between longitudinal changes in lipid profiles and dyslipidemia and ischemic stroke in a hypertensive *** Between 2013 and 2014,6094 hypertension individuals were included in this,and ischemic stroke cases were documented to the end of *** changes of lipid were stratified into four groups:(1)Normal was transformed into normal group;(2)Abnormal was transformed into normal group;(3)Normal was transformed into abnormal group;and(4)Abnormal was transformed into abnormal *** examine the link between longitudinal changes in dyslipidemia along with its components and the risk of ischemic stroke,we utilized multivariate Cox proportional hazards models with hazard ratio(HR)and 95%*** The average age of the participants was 62.32 years±13.00 years,with 329 women making up 54.0%of the *** the course of a mean follow-up of 4.8 years,143 ischemic strokes *** normal was transformed into normal group was used as a reference,after full adjustments,the HR for dyslipidemia and ischemic stroke among abnormal was transformed into normal group,normal was transformed into abnormal group and abnormal was transformed into abnormal Wei CC et *** changed and ischemic stroke WJCC https://*** 2 February 6,2025 Volume 13 Issue 4 group were 1.089(95%CI:0.598-1.982;P=0.779),2.369(95%CI:1.424-3.941;P<0.001)and 1.448(95%CI:1.002-2.298;P=0.047)(P for trend was 0.233),*** In individuals with hypertension,longitudinal shifts from normal to abnormal in dyslipidemia-particularly in total and low-density lipoprotein cholesterol-were significantly associated with the risk of ischemic stroke.

关键词： Longitudinal change Hypertension Dyslipidemia Lipid profile Ischemic stroke

Investigating Müller glia reprogramming in mice: a retrospective of the last decade, and a look to the future

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Neural Regeneration Research 2025年第4期20卷 946-959页

作者： Zhiyuan Yin Jiahui Kang Xuan cheng Hui Gao Shujia Huo Haiwei Xu Key Lab of Visual Damage and Regeneration&Restoration of Chongqing Southwest Eye HospitalSouthwest HospitalThird Military Medical University(Army Medical University)ChongqingChina

Müller glia,as prominent glial cells within the retina,plays a significant role in maintaining retinal homeostasis in both healthy and diseased *** lower vertebrates like zebrafish,these cells assume responsibility for spontaneous retinal regeneration,wherein endogenous Müller glia undergo proliferation,transform into Müller glia-derived progenitor cells,and subsequently regenerate the entire retina with restored ***,Müller glia in the mouse and human retina exhibit limited neural reprogramming.Müller glia reprogramming is thus a promising strategy for treating neurodegenerative ocular disorders.Müller glia reprogramming in mice has been accomplished with remarkable success,through various *** in molecular,genetic,epigenetic,morphological,and physiological evaluations have made it easier to document and investigate the Müller glia programming process in ***,there remain issues that hinder improving reprogramming efficiency and ***,understanding the reprogramming mechanism is crucial toward exploring factors that will improve Müller glia reprogramming efficiency,and for developing novel Müller glia reprogramming *** review describes recent progress in relatively successful Müller glia reprogramming *** also provides a basis for developing new Müller glia reprogramming strategies in mice,including epigenetic remodeling,metabolic modulation,immune regulation,chemical small-molecules regulation,extracellular matrix remodeling,and cell-cell fusion,to achieve Müller glia reprogramming in mice.

关键词： cell fusion chemical small-molecules epigenetic extracellular matrix immune metabolic mice Müller glia neurodegenerative diseases reprogramming retina regeneration