二苯并噻吩结构和性质的理论研究

为了探究煤中噻吩类有机硫化合物降解规律,采用密度泛函理论来对煤的一种含硫模型化合物进行量子化学方面的计算与研究。采用Materials Studio中的Dmol~3程序分析了与煤有关的含硫模型化合物二苯并噻吩(DBT)的结构和相关性质(键角键长、电荷、振动频率、热力学性质、分子反应活性及稳定性)。计算结果显示处于噻吩环结构中的C—S键键能和C—C键键能相等,噻吩环中的C—S键键能大于非环中的C—S键键能;预测噻吩中C—S键更难断裂;模型化合物中的S原子处HOMO伸展较大,是给电子的位置,S原子易失去电子发生反应。     

不对称1,2,4,5-四嗪衍生物的合成和晶体结构研究

以三氨基胍硝酸盐为原料,通过环化、氧化和肼化反应,合成了八个不对称1,2,4,5-四嗪衍生物,通过元素分析、1 H NMR、IR、MS对产品进行了结构表征。单晶X-射线衍射研究结果表明,N-环己基-6-(3,5-二甲基-1 H-吡唑)-1,2,4,5-四嗪-3-胺属于单斜晶系,a=1.3661(4)nm,b=0.6997(2)nm,c=1.5853(5)nm;β=113.262(3);V=1.3921(7)nm3。晶体结构显示,该晶体化合物在分子间N-H…N氢键和π…π共轭的作用下稳定。     

吲哚类衍生物理论研究进展综述

简要介绍了吲哚类衍生物密度泛函理论研究进展,重点评述理论化学方法在吲哚类衍生物的理化性质、计算方法以及化合物结构和性质的主要影响,并介绍了目前这类化合物最常出现的部分理论化学方法。     

四乙酰基二硝基六氮杂异伍兹烷分子结构研究

四乙酰基二硝基六氮杂异伍兹烷(TADNIW)是合成六硝基六氮杂异伍兹烷(HNIW)的中间体。该文用Gaussian 98软件包,采用密度泛函理论B3LYP和标准基组6-31G对所选构型进行了全优化计算,在结构上对TADNIW的键长、键角、二面角、Mu lliken电荷及集居数进行了理论分析,发现笼形化合物的六元环成船式构象,硝基处于桥头,骨架以亚稳态存在。结构分析表明,六元环上N—NO2键相对较稳定,采用一般的硝解条件反应不能进行,作者提出了新的反应机理,即水解-硝化假设:含有酰胺基团的一类化合物在含水的硝化介质中首先发生水解生成相应的仲胺,碱性较强的仲胺再在氮硝化催化剂的作用下,迅速硝化成硝胺。计算得到TADNIW分子总能量为-1 583.375 682 a.u.,前线轨道能量差ΔE(ELUMO-EHOMO)为4.123 eV。计算IR谱图与实验IR谱图对比,误差小于20 cm-1。     

正负离子表面活性剂相互作用的理论和实验研究

Typical cationic and anionic surfactants were chosen and their interactions were calculated by quantumchemical method. Interaction energies are -0.2378kJ·mol~(-1),-3.3394kJ·mol~(-1) and 0.1204kJ·mol~(-1) for the molec-ular pairs with fluocarbon and hydrocarbon chain: C_4H_(10)/C_5H_(12), C_4F_(10)/C_5H_(12), and C_4F_(10)/C_5F_(12), respectively.When hydrophilic group with cationic and anionicions is introduced, interaction energies are -287.40kJ·mol~(-1),-311.18kJ·mol~(-1) and -345.83kJ·mol~(-1). The results show that there is strong static interaction between cationicand anionic surfactants. It has been predicted that mixed monolayer may be formed and surface activity is en-hanced favorably, especially for mixtures of cationic and anionic surfactants with fluocarbon and hydrocarbonchains. The anionic surfactants, sodium octadecylbenzenesulfonate perfluopolyetherbenzenesulonate(ANF-Ⅰ)wassynthesized, mixture effects of ANF-Ⅰ with sodium octadecylbenzenesulfonate or dodecyldimethyl benzylammonium     

linagliptin与靶标DPP4作用机理及分子设计研究

采用分子对接方法对目前刚刚上市的糖尿病抑制剂linagliptin与其靶标DDP4进行研究,建立了合理、有效的对接模型,获得了其活性口袋周围的环境分布情况。并根据这些结论进行了分子设计,对理论设计的新分子通过已建立的模型进行预测,其结果显示它具有比linagliptin更好的对接结合能。该研究结果可为实验工作者合成新药提供理论参考。     

滤饼结构的分形研究

概括地介绍了分形理论在滤饼结构研究中的应用 ,并采用电子扫描与计算机图象处理技术 ,并根据分形理论对以平板陶瓷膜为过滤介质的十字流微滤稳态阶段的滤饼结构进行了理论及实验研究。     

Ceramic Surfaces: Theoretical Studies

This paper surveys recent developments in the calculation of surface energies, surface tensions, defect structure, and related surface phenomena. The way in which theory can complement experiment in understanding the surface behavior of stoichiometric and nonstoichiometric ceramics is discussed.     

环氧丁二酸的结构和性质的理论研究

采用Materials Studio中的Dmol3程序对环氧丁二酸的结构和相关性质(键角键长、Mulliken电荷、振动强度、热力学性质、分子得失电子能力和稳定性)进行了理论性研究。通过Dmol3中的geometry optimization计算出各原子的电荷、振动频率等性质。计算结果明环氧丁二酸分子容易得到电子,并且环氧基上氧原子是与其它物质亲电反应的作点。     

麝香酮结构的理论探讨

论述了到目前为止反映在麝香酮结构上的混乱。应用一种全新概念提出了一种全新的结构（１１）。并提出了包括其它大环酮在内的理论性预言五则。     

Theoretical Studies of the Electronic Properties of Ceramic Materials

The first-principles orthogonalized linear combination of atomic orbitals (OLCAO) method for electronic structure studies has been applied to a variety of complex inorganic crystals. The theory and the practice of the OLCAO method in the local density approximation are discussed in detail. Recent progress in the study of electronic and optical properties of a large list of ceramic systems are summarized. Eight selected topics on different ceramic crystals focusing on specific points of interest are presented as examples. The materials discussed are AIN, Cu₂O, β-Si₃N₄, Y₂O₃, LiB₃O₅, ferroelectric crystals, Fe-B compounds, and the YBa₂Cu₃O₇ superconductor. The results include the band structure, density of states, charge density distribution, spin density distribution, effective charges, total energy and totalenergy-derived results, optical absorption, positron annihilation spectra, and more. Extension of the band theoretical approach to the study of other areas of fundamental ceramic science is also discussed.     

三联芴衍生物TFDPA光电性质的理论研究

三联芴衍生物TFDPA是一种新合成的可应用于OLEDs的多功能蓝光材料。本文采用量子化学方法对其光电性质进行理论研究,结果表明TFDPA具有很强的刚性结构,优良的空穴注入传输性能,且发深蓝色光,与实验数据相符,在理论上进一步证实其在OLEDs中的潜在应用。     

Theoretical Studies on the Mechanism of Hydrolysis of Nitroguanidine by AM1 Method

The mechanism of hydrolysis of nitroguanidine has been studied theoretically. The molecular geometries have been fully optimized at AM1 level of theory for reagent, activated and product complexes for hydrolysis of nitroguanidine in neutral, acidic and alkaline media, respectively. In neutral and acidic media, both activated complexes have four-membered ring structures, and the reaction-coordinated eigenvectors show heavy-atom reorganization and proton transfer to be truly concerted in both cases. In alkaline medium, the hydrolysis also involves activated complex. The calculated activation energies for the hydrolysis of nitroguanidine in neutral, acidic and alkaline media are 278.2 kJ/mol, 330.2 kJ/mol and 213.0 kJ/mol, respectively.     

4,6-二硝基苯并氧化呋咱(DNBF)合成反应及动力学的理论研究

采用B3LYP方法,在cc-pVTZ基组水平下,对2,4,6-三硝基叠氮苯(TNAB)脱去一分子氮气合成4,6-二硝基苯并氧化呋咱(DNBF)的反应历程中,所涉及的各驻点(包括反应物、产物及过渡态)进行几何结构优化和振动频率分析,采用内禀反应坐标理论(IRC)获得反应的最小能量路径(MEP).最后,通过VKLab程序包...     

Theoretical Aspects of the Role of Fibre Structure in Dyeing

A comparison is made between the pore theory and the free-volume theory as applied to the diffusion of dyes through fibres. The usefulness and the limitations of the theories are discussed, and the use of the free-volume theory for explaining the mechanism of carrier action during dyeing is described.     

Theoretical Studies of the Grotthuss Mechanism in Biological Proton Wires

The structural, dynamic, and thermodynamic properties of proton wires are examined. Detailed molecular aspects of both hop and turn steps of the Grotthuss mechanism for proton conduction along single-file chains of water molecules in model nonpolar pores and in the gramicidin A channel are reviewed, and new simulation results are presented. The Grotthuss mechanism is discussed and analyzed in terms of hydrogen-bonded network structure and connectivity, and the properties of proton wires are contrasted to those of bulk water. General considerations regarding the biological relevance of such studies are proposed.     

用拉曼光谱研究碳纤维的结构

激光拉曼光谱（LRS）可用来研究碳纤维和石墨纤维的结构。单晶石墨在1580cm^-1（G线）只有一条谱带，对于多晶碳纤维在1355cm^-1（D线）处还可观察到另一条谱带。这归因于结晶尺寸效应。两者的相对强度比月取决于热处理温度（HTT）。随着HTT的提高，所得碳纤维具有小的R值和大的La。T与La之间存在线性关系，可用来表征碳纤维的结构。     

Theoretical and Experimental Studies on Blast Wave Propagation in Air

High pressure and temperature are produced when high explosives are detonated in open air. The heat of detonation of the explosive compound, peak pressure, and temperature of the blast wave are important blast parameters. A blast wave generated due to explosion propagates into the air medium at supersonic speed until the pressure in the blast zone is released completely. The intensity of the impact by the blast wave on any intervening solid object depends on the blast parameters and the speed of propagation of the blast wave. A theoretical analysis is carried out to predict the pressure produced in the expanding blast zone as function of distance and time by analytically solving the governing equations. The initial peak pressure and temperature of blast wave, which are required in the theoretical analysis, were calculated making use of the blast wave theory. For comparison, experiments were conducted by detonating different weights of high explosives, and pressures were recorded at various distances from the blast point. The high explosives used in the experiments were TNT (0.045, 0.5, 1, 15, and 40 kg) and Composition B (0.045, 0.5, 1, and 15 kg). The theoretical results are validated by comparison with the experimental data and empirical equations available in literature.     

水性乙烯基聚氨酯胶粘剂结构与性能的研究

本文采用多组份乙烯基单体共聚，通过乳液聚合方式，合成了各种含有活泼H单体的共聚物。研究了结构对性能影响的规律。     

N-甲基二乙醇胺嵌段聚氨酯材料的结构表征和性能研究

以N-甲基二乙醇胺为扩链剂合成了阳离子化及肝素化聚氨酯、重点对其结构进行了表征，分别使用离子型染料染色法、比色法、红外光谱法、元素分析法等方法系统分析了经过离子化以及肝素化处理后聚合物结构的变化，同时采用拉伸试验对其力学性能进行了测试，结果表明聚氨酯经离子化和肝素化处理后，强度有了相当大的提高；通过全血凝固时间实验证明肝素化聚氨酯具有较好的血液相容性，是一种理想的生物医用材料。