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971.
Synthesis,Characterization and Thermal Behaviors of 4-Amino-5-nitro-1,2,3-triazole(ANTZ)and Its Derivatives 总被引:1,自引:0,他引:1
4‐Amino‐5‐nitro‐1,2,3‐triazole (ANTZ) and its derivatives, such as 2‐(4‐amino‐5‐nitro‐1,2,3‐trazole‐1‐yl)‐1,3,5‐trinitrobenzene (T‐ANTZ) and 4‐amino‐5‐nitro‐1,2,3‐triazole (M‐ANTZ), were synthesized and characterized, whose structures were confirmed by IR, NMR and elemental analysis. The thermal behaviors of ANTZ, T‐ANTZ and M‐ANTZ were studied by the methods of DSC and TG‐DTG, and the results showed that there is an obvious melting process of ANTZ with melting point of 278.38°C, while there is no melting process in the thermal behavior of T‐ANTZ and M‐ANTZ (the derivatives of ATNZ). 相似文献
972.
973.
本文以Triton X-100/C10H21OH/H2O体系层状溶致液晶为模板,Ca(NO3)2和(NH4)2HPO4为反应物,在一定的pH条件下,通过三元相图确定了层状液晶单相区域,并合成了羟基磷灰石(HA)纳米颗粒。用傅立叶红外光谱(FTIR),X射线衍射(XRD)和透射电子显微镜(TEM)对产物进行了表征。并考察了不同助表面活性剂浓度和不同表面活性剂浓度对产物的形貌和尺寸的影响。结果表明所制备的HA纳米颗粒平均直径为8~10nm、长度在100nm左右,呈针状。助表面活性剂浓度对HA形貌及尺寸影响不大,但是在一定范围内改变表面活性剂浓度可以起到调控HA纳米颗粒形貌和尺寸的作用。 相似文献
974.
975.
在水热条件下合成了一例新型的多金属氧酸盐二聚物,[Ni(enMe)2]4{[Ni(enMe)2][Ni(enMe)2(H2O)]2[Mo8ⅥV6ⅣO38(VⅤO4)]2}.8H2O(1)(enMe=1,2-丙二胺),利用元素分析、红外光谱分析、粉末X射线衍射、热重分析和单晶X射线衍射表征了其结构。结果表明,化合物(1)属于单斜晶系,P2(1)/n空间群.晶胞参数为a=1.9685(4)nm,b=1.3549(3)nm,c=2.7039(5)nm,α=90°,β=93.94(3)°,γ=90°,V=7.195(2)nm3,Z=4,Dc=2.390g/cm3,Mr=2588.4,μ=3.195mm-1,F(000)=5012,最终R1=0.0743,wR2=0.1861.与此同时,(1)是第一个具有二帽-Keggin型钼钒氧簇的二聚体,它由过渡金属部分[Ni(enMe)2(H2O)]22+连接形成{[Ni(enMe)2][Ni(enMe)2(H2O)]2[Mo8ⅥV6ⅣO38(VⅤO4)]2}8-二聚阴离子. 相似文献
976.
采用量子化学密度泛函理论(DFT)B3LYP/6-31G(d)方法,对4,1,6-MC2B10H1213顶点金属碳硼烷几何构型进行优化,结合有限场(FF)方法计算了它们的极化率和二阶非线性光学(NLO)系数.结果表明,十个13顶点金属碳硼烷分子中1a~6a的二阶NLO系数与其构型纵向扩张呈现相同的规律.分子的前线分子轨道能级差越小,其二阶NLO系数越大.对于不同自旋态的同种金属碳硼烷分子,其偶极矩值为高自旋态大于相应的低自旋态,极化率和二阶NLO系数与自旋多重度没有一致的对应规律,自旋多重度对NLO性质影响不大. 相似文献
977.
Xu F Zhang H Ilavsky J Stanciu L Ho D Justice MJ Petrache HI Xie J 《Langmuir : the ACS journal of surfaces and colloids》2010,26(24):19199-19208
The dispersion of Nafion ionomer particles and Pt/C catalyst aggregates in liquid media was studied using both ultra-small-angle X-ray scattering (USAXS) and cryogenic TEM. A systematic approach was taken to study first the dispersion of each component (i.e., ionomer particles and Pt/C aggregates), then the combination of the components, and last the catalyst ink. Multiple-level curve fitting was used to extract the particle size, size distribution, and geometry of the Pt/C aggregates and the Nafion particles in liquid media from the scattering data. The results suggest that the particle size, size distribution, and geometry are not uniform throughout the systems but rather vary significantly. It was found that the interaction of each component (i.e., the Nafion ionomer particles and the Pt/C aggregates) occurs in the dispersion. Cryogenic TEM was used to observe the size and geometry of the particles in liquid directly and to validate the scattering results. The TEM results showed excellent agreement. 相似文献
978.
Liwei Yan Ying Xue Prof. Dr. Ge Gao Prof. Dr. Jingbo Lan Dr. Fan Yang Xiaoyu Su Dr. Jingsong You Prof. Dr. 《Chemistry (Weinheim an der Bergstrasse, Germany)》2010,16(7):2250-2257
The chiral tris‐monodentate imidazolinyl ligands 1 a – c exhibit a strong tendency to form the discrete, helical [2+3] nanocages 3 ([ 1 2 ?2 3]) with tartaric acids 2 . Circular dichroism (CD) spectra and theoretical calculations reveal that supramolecular handedness of capsulelike architectures is determined only by the chirality of the imidazolinyl ligands rather than tartaric acids. The chirality of imidazolinyl ligands is transferred to the helicity of the complexes through the directed hydrogen bonds between the N3 atom of imidazoline rings and the carboxyl of tartaric acids. These hydrogen‐bonded nanocages can spontaneously self‐assemble into spherical vesicles, during which the hydrogen bonding that arises from the hydroxyl groups of tartaric acids plays a crucial issue. The vesicles formed by [{(S,S,S)‐ 1 a }2( 2 L)3] ( 3 a ) may further evolve into microspheres that gelate organic solvents after being aged at ?20 °C for 24 h, and can also be unprecedentedly transformed to tubular assemblies capable of rigidifying the solvents when subjected to ultrasound irradiation. 相似文献
979.
The secondary metabolites of different Ephedra plants are various. Therefore, the discrimination of different Ephedra plants is significant. An objective, easy-to-use, rapid and pollution-free approach is proposed for discriminating Ephedra plants of different species, habitats and picking times on the basis of diffuse reflectance Fourier transform near infrared spectroscopy (FT-NIRS) measurements and multivariate analysis. The Fourier transform near infrared diffuse reflectance spectra (NIRDRS) were acquired from 37 pulverized samples of Ephedra plants put in glass vials in the near infrared (NIR) region between 10 000 and 4000 cm−1, averaging 64 scans per spectrum at a resolution of 4 cm−1. After spectra processing and data pre-processing, spectral data were analyzed respectively with three multivariate analysis techniques: discriminant analysis (DA), self-organizing map (SOM) and back-propagation artificial neural network (BP-ANN). The proposed method could distinguish not only the Ephedra plants of three species and two habitats but also the plants picked at different times of day without special sample treatment and the use of chemical reagents. The performance indexes of the DA model were 84.2-91.9% and the prediction accuracies of both the SOM and the BP-ANN models reached 93.3-100.0%. 相似文献
980.
Three new caged prenylxanthones (xanthone=9H‐xanthen‐9‐one), named neobractatin ( 1 ), 3‐O‐methylneobractatin ( 2 ), and 3‐O‐methylbractatin ( 3 ), along with eight known compounds, were isolated from the twig of Garcinia bracteata. The structures of the new compounds were elucidated on the basis of 1D‐ and 2D‐NMR experiments, including HMBC, HSQC, 1H,1H‐COSY, and ROESY, as well as HR‐MS analysis. 相似文献