Chemistry of Natural Compounds - Two new chromeno[3,2-c]pyridin derivatives, 8-acetyl-3-(hydroxymethyl)-7-methoxy-10H-chromeno[3,2-c]pyridin-10-one (1) and... 相似文献
Journal of Radioanalytical and Nuclear Chemistry - The simplified 8-oxide system (SiO2-B2O3-Na2O-Al2O3-CaO-TiO2-MoO3-La2O3) has been prepared under two types of cooling methods, and analyzed with... 相似文献
The vapor–liquid phase equilibrium (VLE) data for binary systems of neohexane?+?cyclopentane, neohexane?+?N,N-dimethylformamide (DMF), cyclopentane?+?DMF and ternary system of neohexane?+?cyclopentane?+?DMF were determined with a modified Rose still at 101.3 kPa, and all the binary data passed the Wisniak’s test (D?<?5), which accorded with the thermodynamic consistency. Three activity coefficient models namely, Wilson, NRTL and UNIQUAC were used to correlate VLE data and get binary interaction parameters, then the ternary VLE data of neohexane?+?cyclopentane?+?DMF were estimated based on these model parameters using Aspen Plus software. The estimation values of the three models agree well with the experimental data (σ(T)?<?0.5 K). Moreover, the analysis of the effect of DMF on the vapor–liquid phase equilibrium shows that DMF can act as an effective extractant for the system studied.
The preparation and performance improvement of the spinel coating on the surface of ferritic alloy is of wide interest for its application in the metallic interconnects of the solid oxide fuel cells (SOFCs). The Co Mn2O3 composite coating is prepared on the surface of the Crofer alloy by the composite electrodeposition method. A step-heating thermal conversion process is subsequently used to convert the composite coating into a spinel coating, while a direct-heating process is implemented as the control experiment. Isothermal oxidation tests are then carried out for the prepared samples in order to present the high temperature performance. Scanning electron microscopy (SEM), X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), and area-specific resistance (ASR) are used to analyze the properties of the matrix and coatings. The experimental results reveal that the coatings by step-heating thermal conversion exhibit better performance of electrical conductivity and oxidation resistance than the coatings by direct-heating process. Furthermore, with the increase of oxidation time, the atomic proportion of Cr element diffusing to the surface of the matrix is maintained at about 3%–4% for the samples with spinel coatings by step heating, which effectively prevent the Cr volatilization in the matrix. The preparation of spinel coatings on the ferritic alloy by composite electrodeposition and step-heating thermal conversion is helpful to stimulate new ideas for the development of reliable and cost-effective metallic interconnect. 相似文献
Developing new D-A conjugated polymer system for thermoelectric (TE) application is highly desirable. Herein, a series of random copolymers by incorporating 3,4-ethylenedioxythiophene (EDOT) electron rich units into a diketopyrrolopyrrole (DPP) D-A conjugated polymer were designed and synthesized. Compared to the alternating conjugated copolymer PDPP-3T, the HOMO level of the random copolymers are increased as part of the electron deficiency acceptor DPP units in the polymer chain were superseded by electron rich EDOT, which could contribute to effective p-doping. Moreover, through incorporating EDOT to construct random copolymers, it can also induce an orientation change from face-on dominated to edge-on dominated orientation as well as enhance the packing of copolymer chains, which is beneficial to the charge transport. Under same doping condition, the electrical conductivities of the doped polymers increase and the Seebeck coefficient decrease as the increasing of EDOT content, resulting in an optimized power factor of 6.4 μW m−1 K−2 for the random polymer with EDOT content of 40% which is four times higher than that of alternating conjugated copolymer PDPP-3T. These results demonstrated that constructing random copolymers by incorporating more electronic donors into D-A conjugated polymers may be a promising strategy for developing TE conjugated polymers. 相似文献
Journal of Radioanalytical and Nuclear Chemistry - Differences in the net soil loss and apportionment of wind from water erosion on hillslopes were analyzed and evaluated quantitatively through... 相似文献