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101.
Bi‐Dong Wu Yan‐Gang Bi Fu‐Gang Li Li Yang Zun‐Ning Zhou Jian‐Guo Zhang Tong‐Lai Zhang 《无机化学与普通化学杂志》2014,640(1):224-228
The multi‐ligand coordination compound copper(II) 1,2‐diaminopropane (pn) azide, [Cu(pn)(N3)2]n ( 1 ), was synthesized using pn and azido groups. It was characterized by X‐ray single crystal diffraction, elemental analysis, and FT‐IR spectroscopy. The crystal structure of 1 belongs to the monoclinic system, space group C2/c. The copper(II) cation is six‐coordinated by one pn molecule and four azido ligands with μ‐1 and μ‐1,1,3 coordination modes. Thermogravimetric investigations with a heating rate of 10 K · min–1 under nitrogen showed one main exothermic stage with a peak temperature of 215.7 °C in the DSC curve. The non‐isothermal kinetics parameters were calculated by Kissinger and Ozawa methods, respectively. The heat of combustion was measured by oxygen bomb calorimetry, and the enthalpy of formation, the critical temperature of thermal explosion, the entropy of activation (ΔS≠), the enthalpy of activation (ΔH≠), and the free energy of activation (ΔG≠) were calculated. The measurements showed that 1 has very high impact, friction, and flame sensitivities. 相似文献
102.
103.
De‐Heng Shi Wen‐Tao Li Jin‐Feng Sun Zun‐Lue Zhu Yu‐Fang Liu 《International journal of quantum chemistry》2012,112(14):2615-2622
The potential energy curves (PECs) of the X2Π and a4Σ? electronic states of the SiF radical have been studied by an ab initio quantum chemical method. The calculations have been made using the complete active space self‐consistent field (CASSCF) method, which is followed by the valence internally contracted multireference configuration interaction (MRCI) approach in combination with several correlation‐consistent basis sets. The effects on the PECs by the core‐valence correlation and relativistic corrections are included. The way to consider the relativistic correction is to use the third‐order Douglas–Kroll Hamiltonian approximation. The relativistic corrections are made at the level of cc‐pV5Z basis set. The core‐valence correlation corrections are performed using the cc‐pCV5Z basis set. To obtain more reliable results, the PECs determined by the MRCI calculations are also corrected for size‐extensivity errors by means of the Davidson modification (MRCI+Q). These PECs are extrapolated to the complete basis set limit by the total‐energy extrapolation scheme. Using these PECs, the spectroscopic parameters are determined and compared with those reported in the literature. With these PECs obtained by the MRCI+Q/CV+DK+56 calculations, the vibrational levels, inertial rotation, and centrifugal distortion constants of the first 20 vibrational state of each electronic state are calculated when the rotational quantum number J equals zero. Comparison with the Rydberg‐Klein‐Rees (RKR) data shows that the present results are reliable and accurate. The molecular constants of the X2Π and a4Σ? electronic states determined by the MRCI+Q/CV+DK+56 calculations should be good prediction for future laboratory experiment. © 2011 Wiley Periodicals, Inc. Int J Quantum Chem, 2011 相似文献
104.
Er^3+/Yb^3+ Codoped Phosphate Glass Fibre with Gain per Unit Length Greater Than 3.0 dB/cm 下载免费PDF全文
We experimentally study a novel fibre with high gain per unit length based on the homemade erbium-ytterbium codoped phosphate glass. The gain and noise characterizations with different pump powers at different wavelengths are investigated. The 1.8-cm-long fibre, dual-pumped by two single mode 980-nm fibre-pigtailed laser diodes, provides a gain per unit length greater than 3.0dB/cm and a noise figure less than 6.SdB. The gain saturation behaviour at 1535nm is obtained and the saturation output power (3 dB compression) is greater than 5 dBm. 相似文献
105.
Zun‐Ting Zhang Yu‐Qing Ma Yong Liang Dong Xue Qing He 《Journal of heterocyclic chemistry》2011,48(2):279-285
Direct synthetic methods of 6,7‐diphenylpyrazolo[1,5‐a]pyrimidine derivatives have been developed. Cyclocondensation of isoflavones with 3‐aminopyrazole in the presence of sodium methoxide as alkali promoter gave 6,7‐diphenylpyrazolo[1,5‐a]pyrimidines in moderate to good yields. J. Heterocyclic Chem., (2011). 相似文献
106.
Bi‐Dong Wu Prof. Dr. Tong‐Lai Zhang Shi‐Min Tang Li Yang Jian‐Guo Zhang Zun‐Ning Zhou 《无机化学与普通化学杂志》2012,638(14):2347-2352
The environmentally friendly energetic salt (ATZ)(TNPG) (ATZ = 4‐amino‐1, 2, 4‐triazole, TNPG = trinitrophloroglucinol) was synthesized and characterized by elemental analysis and FT‐IR spectroscopy. The crystal structure was determined by X‐ray single crystal diffraction. It crystallizes in monoclinic space group P21/c and its crystal density is 1.832 g · cm–3. Thermal decomposition mechanisms were investigated through differential scanning calorimetry (DSC) and thermogravimetric analysis (TGA). In addition, the experimental data showed that the energy of combustion was approximately equal to the energies of combustion of RDX (1, 3, 5‐trinitro‐1, 3, 5‐triazacyclohexane) and HMX (1, 3, 5, 7‐tetranitro‐1, 3, 5, 7‐tetraazocane). The non‐isothermal kinetics parameters were also studied by applying Kissinger's, Ozawa's, and Starink's methods. Determination of the sensitivities revealed higher sensitivities of (ATZ)(TNPG) as compared to (ATZ)(PA) (PA = picrate). 相似文献
107.
应用相对论效应的密度泛函理论,系统研究了一系列稳定的中空类管状AunSi12(n=25, 30, 35, 40, 45, 50, 55, 60)团簇. AunSi12可以通过在不同长度的单壁Au纳米管(5, 5)的两端戴帽由二十面体Au20Si12平分的两个相同半球构建而成.计算结果显示,Si原子的掺杂使得AunSi12的结构变得更加紧密且加强了相应的类管状Au团簇的稳定性.最高占据分子轨道(HOMO)和最低未占据分子轨道(LUMO)之间的能隙值在0.041 eV至0.138 eV区间,表明AunSi12具有较高的化学活性.电子结构分析显示,Si原子和Au原子之间的p-d轨道杂化在形成和维持AunSi12的类管状结构方面发挥了重要作用.Hirshfeld电荷分析显示,电荷从Au原子转移到Si原子上,Aun... 相似文献
108.
Molecular Characterization of Anisotropic Musielak–Orlicz Hardy Spaces and Their Applications 下载免费PDF全文
Let A be an expansive dilation on R~n and φ:R~n× [0,∞)→[0,∞) an anisotropic Musielak–Orlicz function.Let H_A~φ(R~n) be the anisotropic Hardy space of Musielak–Orlicz type defined via the grand maximal function.In this article,the authors establish its molecular characterization via the atomic characterization of H_A~φ(R~n).The molecules introduced in this article have the vanishing moments up to order s and the range of s in the isotropic case(namely,A:=2I_(n×n)) coincides with the range of well-known classical molecules and,moreover,even for the isotropic Hardy space H~p(R~n)with p∈(0,1](in this case,A:=2I_(n×n),φ(x,t) :=t~p for all x∈R~n and t∈[0,∞)),this molecular characterization is also new.As an application,the authors obtain the boundedness of anisotropic Calderón–Zygmund operators from H_A~φ(R~n) to L~φ(R~n) or from H_A~φ(R~n) to itself. 相似文献
109.
The fuzzification of (positive implicative) pseudo-ideals in a pseudo-BCK algebra is discussed, and several properties are investigated. Characterizations of a fuzzy pseudo-ideal are displayed. 相似文献
110.
Fuzzification of a fantastic filter in a lattice implication algebra is considered. Relations among a fuzzy filter, a fuzzy fantastic filter, and fuzzy positive implicative filter are stated. Conditions for a fuzzy filter to be a fuzzy fantastic filter are given. Using the notion of level set, a characterization of a fuzzy fantastic filter is considered. Extension property for fuzzy fantastic filters is established. The notion of normal/maximal fuzzy fantastic filters and complete fuzzy fantastic filters is introduced, and some related properties are investigated. 相似文献