A Novel Three-dimensional Triazole-based Zinc(Ⅱ) Coordination Polymer Controlled by the Spacers of Dicarboxylate Ligand with(4~2,6~2,8~2)(4,6~2,8~3) Topology

A novel mixed-ligand coordination polymer [Zn(BTA)(ip)0.5]n(1, HBTA = benzotriazole, H2 ip = isophthalic acid) has been synthesized under hydrothermal conditions, which was further characterized by X-ray diffraction, IR spectrum, elemental analysis and TG-DTA experiments. Complex 1 crystallizes in monoclinic system, space group Pnma with a = 8.9731(5), b = 22.0477(12), c = 10.0217(5) ?, V = 1982.66(18) ?3, Z = 8, C10 H6 ZnN3 O2, Mr = 265.55, Dc = 1.779 g/cm3, μ = 2.462 mm-1, F(000) = 1064, the final R = 0.0225 and wR = 0.0652 with I 2?(I). This complex is a 3 D framework with the(42,62,82)(4,62,83) topology. Furthermore, the thermal stability of complex 1 is observed to be dependent on the polymeric structure nature. Strong solid-state luminescence emissions suggest that complex 1 is a good candidate for light emission materials.     

指向高中生物理概念形成的认知分层进阶教学——以“惯性概念”的形成和运用为例

高中生头脑中物理概念的形成和对物理规律的认知,可按照"由感性到理性""由具体到抽象""由简单到复杂"的进阶次序,分为若干个认知层级.基于"概念进阶层级模型",结合高中生认知特点,设计了利于物理概念或规律学习的认知进阶层级模型,并以"牛顿第一定律"的教学实践为例,通过实验研究,发现基于认知进阶的分层教学设计对引导学生"惯性概念"的形成有较好的成效,并且对提升学生运用"惯性概念"分析解决问题的能力起到积极作用.     

如何学好高中物理

高中物理是对思维能力要求较高的一门学科．在学习高中物理过程中应该针对其特点，采取相应的学习方法，才能不断地提高物理思维能力，提高物理成绩，达到事半功倍的效果．     

亚/超临界乙醇液化秸秆纤维素解聚反应研究与机理初探

利用间歇式高压反应釜,在反应温度200～330 ℃、乙醇用量0～150 mL条件下,考察了亚/超临界乙醇直接液化秸秆纤维素的解聚行为,并初步探讨了其液化机理。结果表明,反应温度、乙醇用量和反应停留时间对秸秆纤维素的液化均有显著影响,反应温度由200 ℃升高至330 ℃,重油和气体收率分别增加了12.55%、28.83%;乙醇用量增加,反应压力随之升高,乙醇进入超临界状态,残渣和气体收率相比单纯热裂解分别降低11.10%和8.44%。通过GC/MS、FT-IR分析生物油组分和残渣特性,表明秸秆纤维素在亚/超临界乙醇中断键裂解,且酮类和乙酯类化合物是生物油的主要成分。     

液质联用分析美伐他汀的有关物质

美伐他汀(mevastatin,结构见图1)是肝脏合成胆固醇的限速酶--羟甲基戊二酸单酰辅酶A(HMG-CoA)还原酶抑制剂,对体内降低胆固醇有积极作用,它的一种衍生物--普伐他汀在降低胆固醇方面有更强的药性,因而美伐他汀被作为生产普伐他汀的原料.     

物理概念图式进阶的理论探讨

把物理图式和学习进阶理论结合起来,从图式本体、学习进阶的本质、物理图式的形成过程和结构等方面讨论了它们之间的联系,认为学习者头脑中的物理概念和规律的学习进阶实质上是物理图式的进阶过程.在此基础上,利用郭玉英教授和Knut Neumann等的研究成果,提出了“物理概念图式进阶的层级模型”和“物理概念图式学习进阶教学的分析框架”,旨在有利于教学实践中参考应用.     

Compression behavior and spectroscopic properties of insensitive explosive 1,3,5-triamino-2,4,6-trinitrobenzene from dispersion-corrected density functional theory

Using dispersion corrected density functional theory, we systematically examined the pressure effect on crystal structure, cell volume, and band gap of 1,3,5-triamino-2,4,6-trinitrobenzene(TATB) to understand its extraordinary chemical stability. Analysis of the Mulliken population and the electron density of states implied a possible charge transfer in TATB with increasing pressure. Raman and infrared spectra of TATB under hydrostatic pressure up to 30 GPa were simulated.The observed strong coupling between NH_2 groups and NO_2 groups with increasing pressure, which is considered to have a tendency of energy transfer with these vibrational modes, was analyzed. The pressure-induced frequency shift of selected vibrational modes indicated minor changes of molecular conformation mainly by the rotation of NH_2 groups. Compression behavior and spectroscopic property studies are expected to shed light on the physical and chemical properties of TATB on an atomistic scale.     

桌面式激光驱动冲击波技术及其在含能材料分子反应机制研究中的应用

利用小型化桌面式脉冲激光驱动冲击波可实现材料的快速动态加载,具有成本低、实验重复频率高、加载速率超高等特点。介绍了桌面式激光驱动冲击技术的研究工作,以及该技术在含能材料冲击点火分子反应机制研究中的应用。目前已搭建的纳秒激光驱动冲击波实验系统可以实现上升时间仅为几纳秒、峰值压力不小于2 GPa的超快动态加载,并发展了相应的冲击特性表征技术。利用该实验系统,研究了典型含能材料RDX的冲击感度,发现冲击高压导致的分子内电荷转移是影响材料感度的关键因素,高压下RDX分子杂环上的电子向NO2转移并导致硝基的反应感度增加。该研究成果为认识RDX的冲击反应机制提供了一定的实验依据。通过现有的以及即将开展的工作,希望能够建立一套完整的技术手段,为从分子层次上研究含能材料的冲击反应机理提供实验支持。     

甲烷晶体的晶格能和弹性性质: 不同方法及泛函的评估

通过对甲烷晶体进行结构、晶格能和弹性特性的研究, 评估了不包含和包含色散能量修正的密度泛函理论的性能. 我们分别利用不包含色散能量修正的密度泛函理论(DFT) (包含不同的标准泛函和杂化泛函)和包含色散能量修正的密度泛函理论(DFT-D)计算了甲烷晶体特性, 并与实验作对比. 尽管DFT-D 与传统密度泛函理论及杂化密度泛函理论相比, 修正了甲烷晶体中的范德华(vdW)相互作用, 但是一些修正方案过分修正了这种相互作用. 因此, 人们在使用DFT-D方法时务必谨慎.     

Unreacted equation of states of typical energetic materials under static compression:A review

The unreacted equation of state(EOS) of energetic materials is an important thermodynamic relationship to characterize their high pressure behaviors and has practical importance. The previous experimental and theoretical works on the equation of state of several energetic materials including nitromethane, 1,3,5-trinitrohexahydro-1,3,5-triazine(RDX),1,3,5,7-tetranitro-1,3,5,7-tetrazacyclooctane(HMX), hexanitrostilbene(HNS), hexanitrohexaazaisowurtzitane(HNIW or CL-20), pentaerythritol tetranitrate(PETN), 2,6-diamino-3,5-dinitropyrazine-1-oxide(LLM-105), triamino-trinitrobenzene(TATB), 1,1-diamino-2,2-dinitroethene(DADNE or FOX-7), and trinitrotoluene(TNT) are reviewed in this paper. The EOS determined from hydrostatic and non-hydrostatic compressions are discussed and compared. The theoretical results based on ab initio calculations are summarized and compared with the experimental data.