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A series of hydrotalcite‐derived nickel catalysts were synthesized and employed for the direct amination of biomass‐based furfuryl alcohol with NH3 via the hydrogen borrowing strategy. The effects of the Ni/Al molar ratio and calcination temperature of the NiAl hydrotalcite‐like precursors on the performance of the NixAl‐CT catalyst were investigated. The systematic characterization showed that the synergistic catalysis of the metal and acid‐base sites was of vital importance for the amination of alcohols. In particular, the Ni2Al‐600 catalyst with high amount of Ni0 sites (1.26 mmol g−1) and suitable density of acid‐base sites (0.71 mmol g−1 and 1.10 mmol g−1, respectively) exhibited the best dehydrogenation capability and therefore excellent catalytic activity. An 84.1 % yield of furfurylamine with complete conversion of furfuryl alcohol was obtained under the reaction conditions of 180 °C and 0.4 MPa NH3 in 36 h. The presence of Ni3N in the spent catalyst, confirmed by XRD, TEM and XPS characterizations, was demonstrated to be responsible for the deactivation of the NixAl‐CT catalyst. In addition, the Ni2Al‐600 catalyst exhibited satisfactory performance toward another important biomass‐related transformation of 5‐(aminomethyl)‐2‐furanmethanol to 2,5‐bis(aminomethyl)furan, with a yield of 70.5 %. [ABSTRACT FROM AUTHOR]

A packed bed is a good heat-storage method because of its simple structure, low cost, and good heat-transfer performance. Packed beds generally have a thermocline temperature distribution. This study analyzes a molten-salt thermocline storage system packed with a sensible heat material based on simulation and experimental research. The relationships between heat transfer and the characteristic parameters of the filling material, charging time, and initial conditions are obtained. Investigation results show that the thickness of the thermocline layer reduces with the increase in volume heat capacity but increases with time. The equivalent diameter of particles almost has zero effect on the thermocline thickness, and porosity has an indirect impact on the thickness of the thermocline layer but influences the movement speed of the thermocline. The maximum temperature difference between the fluid and solid decreases, but the range of temperature differences increases with time. [ABSTRACT FROM AUTHOR]

N‐doped porous carbons were prepared from mung bean flour by chemical activation with calcium chloride and urea. Adjusting the precursor and preparation temperature had significant effect on the graphitization, specific surface area, porosity and surface chemical composition of the porous carbons. The material prepared from the mixture of mung bean flour, urea, and calcium chloride at 800 °C was the optimal sample. It exhibited an excellent specific capacitance (247.2 F g−1 at 2 mV s−1 and 300.5 F g−1 at 1 A g−1, respectively), outstanding rate performance (178.6 F g−1 at 200 and 225 F g−1 at 100 A g−1, respectively) and good durability (93.2 and 97.5% capacitance retention after 10000 cyclic voltammograms and 2000 galvanostatic charge/discharge, respectively) in 6 M KOH. The structure‐performance relationships reveal that the excellent specific capacitance of this sample arises from its plentiful porosities, abundant doped‐N and high carbonation. N‐doped porous carbons were prepared from mung bean by chemical activation with calcium chloride and urea. The CaCl2 enhances surface area and urea increases doped‐N of mung bean carbons. The optimal sample show superior specific capacity (300.5 F g−1 at 1 A g−1), rate performance and durability. The excellent specific capacitance of this sample arises from its plentiful porosities, abundant doped‐N and high carbonation. [ABSTRACT FROM AUTHOR]

The plasticizing and thermostabilizing effect of poly(ethylene glycol)-polyhedral oligomeric silsesquioxane ( PEG-POSS) on poly(vinyl chloride) ( PVC) is discussed thoroughly in this work. As PEG-POSS content increases, PVC becomes more flexible and the decomposition temperature of PVC increases slightly. Meanwhile, the temperature of maximum HCl emission is elevated from 265.3 °C in neat PVC to 285.7 °C in PVC nanocomposites, with the peak intensity of HCl emission decreased by 30.8%, and a new lower intensity of HCl emission peak appearing at much higher temperature (around 370 °C), which is in accordance with the maximum degradation temperature of PEG-POSS. Thereby, a possible dehydrochlorination mechanism is suggested according to the fact that the electron donor effect of ether groups would stabilize the CCl bonds by means of more electron cloud stacked in those bonds, which agrees with Fourier transform infrared and X-ray photoelectron spectroscopy experiments in terms of hydrogen bonds. © 2016 Society of Chemical Industry [ABSTRACT FROM AUTHOR]

Phase change materials are most potential candidates for storing solar thermal energy with large enthalpy and high exergy. However, the intrinsic drawback such as poor optical absorptive capacity, low thermal conductivity and poor tensile strength restrict the thermal efficiency of phase change materials. To overcome drawback, expanded graphite is used to encapsulate the paraffin then thermoplastic elastomer is used to mix with the powders with twin-screw extrusion technology. The highly flexible phase change composite shows a melting enthalpy of 124.6 J g−1 and a thermal conductivity of 2.2 W m−1 K−1 with 70% of expanded graphite/paraffin. The tensile strength of 2.1 MPa and a breaking elongation of 220%. This flexible phase change composite demonstrates good photo-thermal energy charging/discharging property and shows much larger exergy than traditional fluids in the solar thermal energy systems. • ①A flexible phase change composite with enthalpy of 124.6 J g−1 and a thermal conductivity of 2.2 W m−1 K−1. • ②The phase change composite has tensile strength of 2.1 MPa and a breaking elongation of 220%. • ③This phase change composite shows good photo-thermal energy charging/discharging property and large exergy. [ABSTRACT FROM AUTHOR]

A novel donor-acceptor-donor (D-A-D) type chromophore, named BDP-dBDT , with a boron dipyrromethene (BODIPY) linked through alkynyl with two benzo [1,2-b:4,5-b’]dithiophene (BDT) terminal donors was designed and synthesized for solution-processed small molecule bulk heterojunction (BHJ) solar cell. The thermal and optochemical properties, BHJ morphology and solar cell performance were investigated. The new molecule shows panchromatic absorption with narrow optical band gap and high molar extinction coefficient. Moreover, the molecule displays deep highest occupied molecular orbital (HOMO) and lowest unoccupied molecular orbital (LUMO) energy levels. The BHJ morphology was systematically optimized by additives, thermal annealing (TA) and solvent vapor annealing (SVA). Processed by a combination of TA and SVA treatments, the BDP-dBDT :PC 71 BM device exhibits a short-circuit current density ( J sc ) of 12.98 mA cm −2 , and a power conversion efficiency (PCE) of 5.61%, which is one of the best values among the ever reported BODIPY based organic solar cells. [ABSTRACT FROM AUTHOR]

Phase change materials are widely used as thermal capacitors in solar thermal systems. The phase change materials with carbon materials could directly absorb the solar energy and transfer to water for building heating, while are rarely reported. In this work, an Ethylene-Propylene-Diene Monomer based phase change material with expanded graphite is prepared. The photo-thermal performance of the phase change material is investigated with combined experimental and numerical method. The SiO 2 aerogel is first used as the thermal insulator in the solar thermal systems with the high transmittance and low thermal conductivity. The effect of the phase change material height and tube passes number on the photo-thermal performance of the phase change materials are calculated. The results show that the new material has a tensile strength of 3.6 MPa, enthalpy of 126.8 J g−1，and thermal conductivity of 1.106 W m−1 K−1. The phase change material with SiO 2 aerogel could resist heat lost on the surface. The phase change material has good photo-thermal performance in solar thermal systems, could heat more than 200 L of hot water at daytime. Image 1 • A flexible phase change composite with enthalpy of 126.8 J g−1 and a thermal conductivity of 1.1 W m−1 K−1. • The phase change composite has tensile strength of 3.6 MPa. • The SiO 2 aerogel is first used as the thermal insulator for photo-thermal conversion. • This phase change composite could heat more than 200 L of hot water at daytime. [ABSTRACT FROM AUTHOR]

Interfacial interaction is one of the key factors to improve comprehensive properties of polymer/inorganic filler nanocomposites. In this work, a new interfacial interaction called electron transferring interaction is reported in the nitrile-butadiene rubber/halloysite nanotubes (NBR/HNTs) nanocomposites. The X-ray photoelectron spectroscopy (XPS) and in-situ controlling temperature Fourier transform infrared spectroscopy (FTIR) have confirmed that electrons of electron-rich −CN groups in NBR can transfer to the electron-deficiency aluminum atoms of HNTs, which packs a part of NBR molecules onto the surface of HNTs to form bound rubber and stabilize the homogeneous dispersion of HNTs with few agglomeration as revealed by scanning electron microscope (SEM) and dynamic mechanical analysis (DMA) performances, even at high HNTs addition, resulting in high light transmittance. The tensile strength of NBR/30wt%HNTs nanocomposites is about 291% higher than pure NBR, without sacrificing the elongation at break. [ABSTRACT FROM AUTHOR]