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61.
金属卤化物MCl2(M=Pb2+,Cd2+,Co2+)分别与苯并噻唑(btz)在浓盐酸中、80 ℃下反应,合成了3种有机-无机杂化化合物:(btzH)[(PbCl3)] (1),(btzH)2[CdCl4]·2H2O (2)和(btzH)2[CoCl4]·2H2O (3),其中化合物2和3结构相似。对化合物1~3进行了粉末衍射、红外和紫外光谱、元素分析、热重分析以及X射线单晶衍射表征。荧光测试发现:化合物1~3在393 nm处有发射峰,该荧光来源于苯并噻唑环中电子的π…π跃迁。 相似文献
62.
合成得到了2个新的有机-无机杂化化合物{(4-CH3-Bz-4-Ph-Py)[PbI3]}n(1)(其中4-CH3-Bz-4-Ph-Py是4-甲基苄基-4-苯基吡啶阳离子)和{(4-CF3-Bz-4-Ph-Py)[PbI3]}n(2)(其中4-CF3-Bz-4-Ph-Py是4-三氟甲基苄基-4-苯基吡啶阳离子)。对化合物1和2进行了元素分析、粉末X射线衍射等表征,并利用X射线单晶衍射测定了它们的单晶结构。化合物1属于正交晶系,P21212空间群;化合物2与1同构。结构研究表明,化合物1和2中,铅碘八面体通过共边连接方式,形成[Pb3I9]n三链,有机阳离子填充在无机碘化铅链空隙中。 相似文献
63.
A novel electrochemical detection approach for platelet-derived growth factor(PDGF) via "sandwich"structure is reported in this paper. 3D-4MgCO_3 Mg(OH)_2 4H_2O-Au NPs inorganic hybrid composite was utilized as immobilized substrate for sensitive PDGF detection and Pt-Au bimetallic nanoparticles were labelled on PDGF aptamer to indirectly detect PDGF for the first time. The proposed aptasensor exhibited a high catalytic efficiency towards reduction of H_2O_2, hence the sensitive detection of PDGF was achieved.Results showed that the aptasensor exhibited excellent linear response to PDGF, in the range of 0.1 pg/m L–10 ng/m L(4 fmol/L–400 pmol/L), with detection limit of 0.03 pg/m L(1.2 fmol/L). 相似文献
64.
Enhancement of water barrier properties and tribological performance of hybrid glass fiber/epoxy composites with inclusions of carbon and silica nanoparticles 下载免费PDF全文
Water barrier properties and tribological performance (hardness and wear behavior) of new hybrid nanocomposites under dry and wet conditions were investigated. The new fabricated hybrid nanocomposite laminates consist of epoxy reinforced with woven and nonwoven tissue glass fibers and two different types of nanoparticles, silica (SiO2) and carbon black nanoparticles (C). These nanoparticles were incorporated into epoxy resin as a single nanoparticle (either SiO2 or C) or combining SiO2 and C nanoparticles simultaneously with different weight fractions. The results showed that addition of carbon nanoparticles with 0.5 and 1 wt% resulted in maximum reduction in water uptake by 28.55% and 21.66%, respectively, as compared with neat glass fiber reinforced epoxy composites. Addition of all studied types and contents of nanoparticles improves hardness in dry and wet conditions over unfilled fiber composites. Under dry conditions, maximum reduction of 47.26% in weight loss was obtained with specimens containing 1 wt% carbon nanoparticles; however, in wet conditions, weight loss was reduced by 17.525% for specimens containing 0.5 wt% carbon nanoparticles as compared with unfilled fiber composites. Diffusion coefficients for different types of the hybrid nanocomposites were computed using Fickian and Langmuir models of diffusion. Copyright © 2017 John Wiley & Sons, Ltd. 相似文献
65.
Are there reliable DFT approaches for 13C NMR chemical shift predictions of fullerene C60 derivatives? 下载免费PDF全文
Arthur R. Tulyabaev Ilya I. Kiryanov Ilnaz S. Samigullin Leonard M. Khalilov 《International journal of quantum chemistry》2017,117(1):7-14
The relationships between experimental and theoretical 13C NMR chemical shifts of a pristine fullerene C60, monoadducts from [2 + n] cycloaddition (n = 1–3), and one [2 + 1] bis‐adduct are systematically analyzed for the first time by using diverse quantum‐chemical levels of theory. These levels involved B3LYP, B3PW91, B97‐2, mPW1PW91, PBE1PBE, and X3LYP hybrid functionals combined with 3‐21G, 6‐31G, 6‐31G(d), 6‐31G(d,p), 6‐31G(d,2p), LanL2DZ, and SDDAll basis sets. X3LYP/6‐31G approach is determined to have the lowest deviations from the 13C NMR experimental data compared to the other methods for all the fullerene compounds (mean absolute error value is 0.856 ppm and root mean squared error value is 1.197 ppm). The highest deviations are characteristic for α (sp2 C2/C5/C8/C10) and β (sp2 C6/C7/C11/C12) carbon atoms relative to a functionalization site and for those (sp3 C1/C9) directly attached with a side fragment in the [2 + n] monoadducts (n = 1–3). A probable reason of such deviation is that the approaches do not take into account a contribution of paramagnetic ring currents to 13C NMR chemical shifts. The results will be useful in design of novel fullerene derivatives and in performing unambiguous 13C NMR chemical shift assignments with modern quantum chemistry calculations. 相似文献
66.
《Helvetica chimica acta》2017,100(9)
The synthesis and characterization of chitosan‐silica sulfate nano hybrid (CSSNH ) as a novel and efficient heterogeneous nano catalyst involving acid‐base bifunctional activity is described. The catalytic potency and activity of this eco‐friendly catalyst was investigated in regioselective ring opening of epoxides with carboxylic acids to access structurally diverse 1,2‐diol mono‐esters in good to excellent yields. CSSNH catalyst was characterized using different microscopic and spectroscopic techniques encompassing scanning electron microscopy, transmission electron microscopy, X‐ray diffraction, N2 adsorption isotherm, and Fourier transform infrared spectroscopy. The green nature, cheapness, efficiency, ease of preparation, handling and reusability of this new catalyst makes this catalyst to be useful for green industrial processes. 相似文献
67.
Two new hybrid compounds with chemical formulas [Co(L1)2(H2O)2]2[SiW12O40]·6H2O (1) and [Cu2(C9H22 N)2(L2)2][SiW12O40]·2H2O (2) (L1 = 3,3′-diamino-5,5′-bis(1H-1,2,4-triazole), L2 = 1,2-bis(3-(2-pyridyl)pyrazole-1-ylmethyl)benzene, C9H22 N = tripropylamine) were prepared in a hydrothermal reaction system containing Keggin-type polyoxometalates (POMs), transition metal (TM) salts (cobalt salts and copper salts), and chelate L1/L2 ligands. X-ray structural analysis reveals that 1 and 2 possess 3-D supramolecular host frameworks with large cavities and the polyoxoanions SiW12 reside in these cavities as the guest templates. The photocatalytic activities of 1 and 2 were investigated. Both compounds show efficient catalytic activity for degradation of RhB with 1 > 2. The loading amount of the POM units and the structural features of these POM-based organic-inorganic hybrid compounds may be necessary factors that affect the activity of catalysts in the photocatalytic degradation. 相似文献
68.
69.
《Journal of separation science》2017,40(21):4256-4263
Polypyrrole‐magnetite dispersive micro‐solid‐phase extraction method combined with ultraviolet‐visible spectrophotometry was developed for the determination of selected cationic dyes in textile wastewater. Polypyrrole‐magnetite was used as adsorbent due to its thermal stability, magnetic properties, and ability to adsorb Rhodamine 6G and crystal violet. Dispersive micro‐solid‐phase extraction parameters were optimized, including sample pH, adsorbent amount, extraction time, and desorption solvent. The optimum polypyrrole‐magnetite dispersive micro‐solid phase‐extraction conditions were sample pH 8, 60 mg polypyrrole‐magnetite adsorbent, 5 min of extraction time, and acetonitrile as the desorption solvent. Under the optimized conditions, the polypyrrole‐magnetite dispersive micro‐solid‐phase extraction with ultraviolet‐visible method showed good linearity in the range of 0.05–7 mg/L (R 2 > 0.9980). The method also showed a good limit of detection for the dyes (0.05 mg/L) and good analyte recoveries (97.4–111.3%) with relative standard deviations < 10%. The method was successfully applied to the analysis of dyes in textile wastewater samples where the concentration found was 1.03 mg (RSD ±7.9%) and 1.13 mg/L (RSD ± 4.6%) for Rhodamine 6G and crystal violet, respectively. It can be concluded that this method can be adopted for the rapid extraction and determination of dyes at trace concentration levels. 相似文献
70.
《Journal of mass spectrometry : JMS》2017,52(1):43-53
The study of the key parameters impacted surface‐assisted laser desorption/ionization‐mass spectrometry is of broad interest. In previous studies, it has been shown that surface‐assisted laser desorption/ionization‐mass spectrometry is a complex process depending on multiple factors. In the presented study, we showed that neither porosity, light absorbance nor surface hydrophobicity alone influence the enhancement phenomena observed from the hybrid metal‐semiconductor complexes versus individual targets, but small changes in the analyte attaching to the target significantly affect laser desorption ionization‐efficiency. By means of Raman spectroscopy and scanning electron microscopy, it was revealed that the formation of an amorphous analyte layer after drying on a solid substrate was essential for the enhanced laser desorption ionization‐signal observed from the hybrid metal‐semiconductor targets, and the crystallization properties of the analyte appeared as a function of the substrate. Obtained results were used for the screening of regular and lactose‐free milk samples through the hybrid metal‐semiconductor target. Copyright © 2016 John Wiley & Sons, Ltd. 相似文献