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111.
Sheng‐Run Zheng Xi‐Ling Wen Zi‐Meng Liu Tao Xie Jing‐Bo Tan Jun Fan Shuang‐Shuang Hou Wei‐Guang Zhang 《无机化学与普通化学杂志》2014,640(10):2057-2061
Two coordination polymers (CPs), namely, [Cu(Hptz)2(Hhba)2]n ( 1 ) [Hptz = 5‐(4‐pyridyl)‐1H‐tetrazole, H2hba = 2‐hydroxybenzoic acid] and [Zn3(ptz)2(hpa)2]n ( 2 ) (H2hpa = 2‐hydroxy‐2‐phenylacetic acid), were synthesized by solvothermal reactions. Both complexes were characterized by elemental analysis, infrared spectroscopy, powder X‐ray diffraction, thermogravimetric analysis, and single‐crystal X‐ray diffraction analysis. Compound 1 exhibits a 2D (4,4) network, where each layer connects to four adjacent layers to construct a 3D supramolecular framework. Compound 2 has a 3D framework structure composed of 1D SUBs, which are formed by both carboxyl and tetrazole groups. The complexes represent two rare examples of CPs constructed from Hptz and organic carboxyl acid ligands. Complex 2 exhibits intense, red‐shifted emissions in the visible region at room temperature. 相似文献
112.
《Comptes Rendus Chimie》2014,17(7-8):641-655
Since the initial discovery of ordered mesoporous silica in early 1990s, considerable innovations were achieved regarding their synthesis, characterization and applications. One of the best outcomes of these intense research efforts is the development of a solid templating method called “nanocasting”, which is based on using mesoporous silica (or carbon) as a rigid template. This solid-to-solid replication method opened the pathway for synthesizing high surface area non-silica mesostructured materials that are challenging to obtain through conventional self-assembly processes which are based on amphiphilic soft structure-directing agents. In particular, the replicated metal oxide mesostructures obtained by this method were found to be highly versatile for a wide range of applications, especially in catalysis, owing to their large specific surface area. Furthermore, the nanocasting method is particularly suited for the synthesis of mixed metal compositions, favored by the possible confinement of mixed precursors in the nanopores of the template. In this account, we discuss some of the recent developments regarding the synthesis of nanocast mixed metal oxides and their perspectives of catalytic applications. It is here the choice of the authors to place emphasis on a few representative examples of compositions (e.g., non-noble metal-based catalysts, perovskites) and catalytic reactions (e.g., hydrogen production, gas-phase oxidation). 相似文献
113.
Textile and dye industries are main sources of dye bearing effluent. In present studies the anaerobic biological degradation of Acid Red 3BN dye water (AR3BNDW) and mixed dye water (MDW) for reduction of color and COD were studied in sequential batch reactor (SBR). The sludge as sources of microorganism was arranged from maize processing bio methanation wastewater treatment plant, which was acclimatized for treatment of AR3BNDW and MDW. After the acclimatization, dyes degradation were studied in SBR At optimum operation condition of hydraulics retention time (HRT) = 2.5 d, and treatment time (tR) = 16 h, AR3BNDW have gone maximum 87% color reduction of 500 mg/L dye, and 82.8% COD reduction of 380 mg/L COD. At same operating condition, 84.5% color reduction of 500 mg/L dye, and 79.42% COD reduction of 413 mg/L COD achieved for MDW. The second order Grau model was fitted well for COD and dye reductions. The kinetics parameter were evaluated for both the dye water. 相似文献
114.
Fault tree analysis (FTA) is a promising quantitative technique for risk analysis in chemical process industries (CPIs). In FTA, a certain sequence of basic events (causes) leads to one specific Top event (critical event of interest). However, the conventional fault tree analysis has the limitations of staticity and uncertainty. The staticity in conventional FTA arises due to its inability to accommodate time-dependent characteristics of the process system. Whereas uncertainty primarily lies in the failure probability data of basic events. This paper proposes an innovative methodology that uses a time-dependent covariate model to update the failure probability values of major contributing basic events in FTA. A novel subclass of the family of phase-type distributions is used to model the covariates corresponding to the basic events. The newly developed methodology is applied for a case study in a chlorine manufacturing facility to estimate the chlorine release probability. The blockage in the pipeline was identified as the significant reason for chlorine release from expert opinion and sensitivity analysis. The results of the proposed model of FTA are compared with that of conventional FTA. 相似文献
115.
116.
We analyze a coherent injection of single electrons on top of the Fermi sea in two situations, at finite-temperature and in the presence of pure dephasing. Both finite-temperature and pure dephasing change the property of the injected quantum states from pure to mixed. However, we show that the temperature-induced mixedness does not alter the coherence properties of these single-electron states. In particular two such mixed states exhibit perfect antibunching while colliding at an electronic wave splitter. This is in striking difference with the dephasing-induced mixedness which suppresses antibunching. On the contrary, a single-particle shot noise is suppressed at finite temperatures but is not affected by pure dephasing. This work therefore extends the investigation of the coherence properties of single-electron states to the case of mixed states and clarifies the difference between different types of mixedness. 相似文献
117.
We analyze a coherent injection of single electrons on top of the Fermi sea in two situations, at finite-temperature and in the presence of pure dephasing. Both finite-temperature and pure dephasing change the property of the injected quantum states from pure to mixed. However, we show that the temperature-induced mixedness does not alter the coherence properties of these single-electron states. In particular two such mixed states exhibit perfect antibunching while colliding at an electronic wave splitter. This is in striking difference with the dephasing-induced mixedness which suppresses antibunching. On the contrary, a single-particle shot noise is suppressed at finite temperatures but is not affected by pure dephasing. This work therefore extends the investigation of the coherence properties of single-electron states to the case of mixed states and clarifies the difference between different types of mixedness. 相似文献
118.
This study was to investigate the optimal additions of the cellulose decomposition reaction to obtain the most yield of 5-HMF and other furan derivatives in various biphasic systems with FeCl_3-CuCl_2 mixed catalysts,and explore its depolymerization kinetics.A series of controllable reactions have been performed under mild environmentally friendly atmosphere.The experiment results showed that49.13 wt% of 5-HMF was the maximum production along with 2.98 wt% other furan derivatives catalyzed by mixed Lewis acid FeCl_3-CuCl_2 under the two phases which included high concentration NaCl aqueous phase and n-butanol organic phase at 190℃ for 45 min.The conclusion suggested that two-phase systems benefited the yield of 5-HMF,furan derivatives via extracting the target products from reaction phase to organic phase to avoid rehydration of 5-HMF.The kinetic calculation revealed the conversion with mixed catalysts had lower reaction apparent activation energy(21.65 kJ/mol,190-230℃) and the reaction rate was faster than that with acid-based catalysts.Based on experiment exploration,the probable mechanism of cellulose decomposition with FeCl_3-CuCl_2 was proposed. 相似文献
119.
利用水热法制备了菊花状的氧化锌纳米棒,并进行表征,将纳米氧化锌掺入纳米金刚石中配制成电泳液,超声分散后电泳沉积到钛衬底上,再经热处理后进行场发射特性的测试.结果表明:未掺混的金刚石阴极样品的开启电场为7.3V/μm,在20V/μm的电场下,场发射电流密度为81μA/cm2;掺混后阴极样品的场发射开启电场降低到4.7~6.0V/μm,在20V/μm电场下,场发射电流密度提高到140~158μA/cm2.原因是纳米ZnO掺入后,增强了涂层的电子输运能力、增加了有效发射体数目,提高了场增强因子β,而金刚石保证了热处理后涂层与衬底的良好键合,形成了欧姆接触,降低了场发射电流的热效应.场发射电流的稳定性随掺混ZnO量的增加而下降,要兼顾场发射电流密度及其稳定性,适量掺入ZnO可有效提高纳米金刚石的场发射性能. 相似文献
120.
In recent decades, high-temperature oxygen reduction reaction on mixed conducting cathodes were investigated intensively by many researchers. Computational approaches as well as electrochemical and spectroscopic studies have been made to elucidate the kinetics. Contribution of oxygen vacancy to the reaction rate was suggested in multiple reports, and plausible reaction pathways were proposed based on density functional theory (DFT) calculations. The picture of oxygen reduction reaction has become clearer in these years. However, there still is a discussion about a credible formula that represents the current–voltage relationships. Discrepancies are found among the reported data on the magnitude of the rate constant and on its dependencies on partial pressure and temperature. The difference is significant between a model electrode and a practical porous electrode. Comparison of the results suggests the existence of series reaction barriers, that is, the surface reaction and subsurface transport, which should be considered for consistent representation of the total electrode process. 相似文献