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A large-area COFTAPB–BPY film with a pore size of 3.9 nm was prepared on a gas–liquid interface by the virtue of the limiting and guiding functions of sodium dodecylbenzene sulfonate, followed by modification by Ni2+ ions with the reversible redox reaction of Ni(II/III), where Ni2+ was evidently anchored on the N in BPY. The obtained COFTAPB–BPY and Ni-COFTAPB–BPY nanofilms could avoid the inevitable aggregation and stacking of bulk COFTAPB–BPY, which facilitated a high specific capacitance of 0.26 mF cm−2 for the COFTAPB–BPY nanofilm and 0.38 mF cm−2 for the Ni-COFTAPB–BPY nanofilm at 0.001 mA cm−2. Considering the pseudocapacitance and double-layer capacitance traits of Ni-COFTAPB–BPY and COFTAPB–BPY nanofilms, the asymmetric Ni-COFTAPB–BPY//COFTAPB–BPY film supercapacitor was assembled with a symmetric COFTAPB–BPY//COFTAPB–BPY film device as a control. The asymmetric Ni-COFTAPB–BPY//COFTAPB–BPY film supercapacitor could enhance the energy density of 273.9 mW h cm−3 at 14.09 W cm−3 from 85.2 mW h cm−3 at 4.38 W cm−3 for the symmetric COFTAPB–BPY//COFTAPB–BPY film device. This work provides a new perspective on the application of self-supporting COF nanofilms as film asymmetric supercapacitors. [ABSTRACT FROM AUTHOR]

This work focused on the mathematical model establishment and accurately forecast the conditions of thermal storage catalytic combustion about ethyl acetate, using platinum/palladium molecular sieve support reaction system. According to the physical properties of ethyl acetate and the mass transfer and continuity equations, a mathematical model was established using FORTRAN programming. The mathematical model was used to calculate the removal rate of ethyl acetate at switching time and processing flow rate. Under the same conditions, the model and experiment proved that the removal rate of ethyl acetate was above 98%, indicating that the model provides a valid data for a deeper understanding of the thermal storage catalytic combustion. The accuracy of the model is verified by the experimentally measured bed temperature when compared with the calculated. This work can provide a valuable tool to prevent the reactor from 'over temperature' or 'flaming out' in thermal storage catalytic combustion process. [ABSTRACT FROM AUTHOR]

Summary: The CoMoO4 microspheres constructed from ultrathin nanosheets were synthesized by means of a simple chemical precipitation using urotropin (C6H12N4) as a soft template, which were used as the electrode materials for supercapacitors. It was found that the CoMoO4 sample with 3 mmol of added urotropin (vs 1 mmol CoCl2) exhibits the uppermost specific capacity value of 89 mAh/g at a current density of 0.25 A/g due to its unique mesoporous structure and large specific surface area. In addition, a hybrid supercapacitor was established by the CoMoO4 microspheres (positive electrode) and activated carbon (AC, negative electrode). The obtained CoMoO4//AC hybrid supercapacitor possesses a specific energy value of 34 Wh/kg at 375 W/kg. Most importantly, this device owns excellent cycle stability with no capacity decay observed after 10 000 cycles. These good electrochemical properties of CoMoO4 microspheres are promising in the practical use fields. [ABSTRACT FROM AUTHOR]

Electrochemical water splitting is an important strategy for the mass production of hydrogen. Development of synthesizable catalysts has always been one of the biggest obstacles to replace platinum‐group catalysts. In this work, a high quality crystal polymer covalent triazine framework [CTF; Brunauer–Emmett–Teller (BET) surface area of 1562.6 m2 g−1] is synthesized and MoS2 nanoparticles are grown in situ into/onto the 1 D channel arrays or the external surface for electrocatalysis [hydrogen evolution reaction (HER)]. The state‐of‐the‐art CTFs@MoS2 structure exhibits superior catalytic kinetics with an overpotential of 93 mV and Tafel slope of 43 mV dec−1, which is improved over most other reported analogous catalysts. The inherent π‐conjugated crystal channels in CTFs provides a multifunctional support for electron transmission and mass diffusion during the hydrogen evolution process. Catalytic kinetics analysis shows that the HER performance is closely correlated to the hierarchical pore parameters and aggregated thickness of MoS2 nanoparticles. This work provides an attractive and durable alternative to synthesize high activity and stable catalysts for HER. [ABSTRACT FROM AUTHOR]

The NiMoO4 sheets were grown on graphitic carbon nitride (g-C3N4) using a very simple chemical precipitation method. The prepared g-C3N4/NiMoO4 can be used as the electrode material of supercapacitors and exhibit a high specific capacitance of 1275 F g−1 at 0.25 A g−1 owing to the interconnected structure and presence of N by the incorporation of g-C3N4. In addition, the g-C3N4/NiMoO4//rGO hybrid supercapacitor was assembled by employing g-C3N4/NiMoO4 and rGO as positive and negative electrode respectively. The assembled hybrid device can exhibit good electrochemical performances, such as the specific capacitance of 146 F g−1, energy density of 90 Wh kg−1 and accepted cycle stability with 70% capacitance retention after 4000 continuous cycles. These results powerfully demonstrate that the prepared g-C3N4/NiMoO4 can be applied as a potential candidate in the electrode material of supercapacitors. [ABSTRACT FROM AUTHOR]

A facile one-pot strategy of using CeBTC MOF as template and precursor was explored to prepare rod-like inverse CeO2-CuO catalysts. The inverse CeO2-CuO catalysts were characterized by using techniques of N2 adsorption and desorption, XRD, TEM, TPR and XPS. The results indicated that the rod-like inverse CeO2-CuO catalysts maintained the shapes of CeBTC MOF templates. The Cu0.71Ce0.29 catalysts exhibited excellent catalytic performance which was attributed to the strong synergistic effect between CuO and CeO2 and subsequent formation of reduced copper species. [ABSTRACT FROM AUTHOR]

BACKGROUND Ionic liquids ( ILs) have been widely used in the field of SO2 separation for gases. In this study, two kinds of guanidinium-based dicarboxylic acid ionic liquids including [1,1,3,3-tetramethylguanidinium][Poly(ethylene glycol) bis(carboxymethyl) ether] ([ TMG][ PBE]) and [1,1,3,3-tetramethylguanidinium] [Suberic acid] ([ TMG][ SUB]) were synthesized, and their absorption and desorption performance of SO2 were investigated. RESULTS The saturated molar ratio of SO2 to [ TMG][ PBE] and [ TMG][ SUB] were 8.74 and 5.96 mol SO2 per mole ILs at 25 °C, respectively. [ TMG][ PBE] saturated with SO2 was easier to desorb and could be recycled at least 5 times without loss of initial performance, while the ability to absorb SO2 by [ TMG][ SUB] was gradually weakened after desorption. The absorption mechanism is discussed. Results showed that SO2 could interact not only with the amino group on the cation but also with the methylene bonded to the carbonyl carbon on the anion for [ TMG][ SUB]. As for [ TMG][ PBE], SO2 could interact with the ether group by S-O ligand interaction, instead of interacting with the methylene group bonded to the carbonyl carbon on the anion. [ TMG][ PBE] show good performance for SO2 capture. CONCLUSION The anion of dicarboxylic acid-based ILs plays an important role in absorption/desorption of SO2 on the basis of the experimental results. © 2016 Society of Chemical Industry [ABSTRACT FROM AUTHOR]

Most salt lakes of Chaidamu circular economy pilot area in Qinghai Province are chloride-type lakes, and many chlorine-contained by-products will be formed during the developing process. How to utilize and transform these by-products has an important significance for the chlorine balance in industry chain of salt lake area. The industrial metabolism process of chlorine element is analyzed from the main planed products in Chaidamu circular economy pilot area master plan. Two main problems that affect the utilization of chlorine element are chlorine element balance and potential pollution to the salt lake caused by calcium chloride. Three transforming and converting approaches are put forward, which are immobilization process that converts chlorine to solid products, transformation process that transforms chlorine to organic products and clean storage of calcium chlorine. If the above approaches can be put into practice, the balance of chlorine element will be achieved in the pilot area. [ABSTRACT FROM AUTHOR]

The removal of the Chinese population bottleneck does not lie in keeping a population of 1.5 billion, but lies in carrying out "the strategy of negative increase in population", that is, reducing the population to a small size, with a population of 0. 3 to 0. 4 billion through three stages. The decrease in the Chinese fertility rate has both its substantial space: scale space, structure space,policy space and comparison space, and its conceptual space. The latter can be removed by improving people's recognition as follows. Firstly, the problem of development and environment is caused by the population in a large scale. Sustainable development does not call for " proper population", which is supported by land productive forces, but calls for " small population", which can keep balance with environment. Secondly, the priority of the population control to the adjustment of age structure is a stipulation of Levels-Scales Theory. Thirdly, the market economy is not everything and the exercising birth control is necessary. The high birth sex ratio does not certainly connected with narrow "birth space" caused by the policy. Finally, to keep a low birth level, we should not stabilize the population in the east while reducing the population in the west, but reduce the population in both places. [ABSTRACT FROM AUTHOR]