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The metal hydrides have great potential for the storage and utilization of hydrogen. Because of the strong exothermic/endothermic effect of H 2 absorption/desorption process, the structure development of metal hydride reactor should mainly focus on the heat transfer enhancement. The new spiral mini-channel reactor is proposed to increase the heat transfer efficiency and H 2 absorption rate. The spiral tubes can not only eliminate the stress produced by temperature changes and volumetric expansions, but also improve the turbulent intensity and heat transfer rate. The numerical model of spiral mini-channel reactor is established, and the simulation results present that the new reactor shows high thermal efficiency and hydrogenation rate. The structure parameters of the reactor are optimized as minor radius of 2.2 mm, axial pitch of 5 mm, major radius of 5.5 mm and tube amount of 3. Furthermore, the operation conditions are investigated. The result indicates that superior performance is obtained for the packing fraction of 0.6 and H 2 pressure over 10 atm during H 2 absorption. With these promising features, this new spiral mini-channel reactor has broad prospects in the hydrogen energy field. [ABSTRACT FROM AUTHOR]

Three new compounds were isolated from the adult insect of Allomyrina dichotoma L. for the first time. A new skeleton compound is named as Allomyrinanoid A ( 1 ) originated from the familiar norbornane derivatives and two new compounds of purine alkaloid are named as adenine-9-methylaldehyde oxime B ( 2 ) and 6- N -methyleneimine-adenine-9-methylaldehyde oxime B ( 3 ). The compounds ( 2 ) and ( 3 ) are the tautomers of imine–enamine and creatively separated form the solvent using column chromatography method. The structures of all isolated compounds were established by spectroscopic methods including analyses of their 1D, 2D NMR and HRESI-MS data, and confirmed by comparison of the literature data. These new components displayed antibacterial activities against both Gram-positive and Gram-negative strain. [ABSTRACT FROM AUTHOR]

Originated from the future trends and requirements for silicone rubber (SR) in harsh work condition of advanced cutting-edge fields (construction, aerospace, marine equipment and automobile, etc), the processing complexity, complex ingredients and unbalanced overall properties of traditional multi-component flame-retarding SR system are limited. The development of mono-component and halogen-free flame retardants with adequate efficiency, durability and strength have been urgently expected for settling the crucial bottleneck issue of SR materials, which can avoid the defects of performance contradictions for long-used multi-component system in previous published work. Under such background, this paper has fabricated a hydrophobic Mn-doped melamine phosphate (H-DTMA@Mn) via facile multi-stage construction strategy that has been confirmed by a series of characterizations. The results have indicated that SR/28 phr H-DTMA@Mn can achieve limiting oxygen index (LOI) of 32.4% and UL-94 V-0 rating. Along with the reduced peak heat release rate, the validity of as-prepared H-DTMA@Mn for raising the flame retardancy of SR has been straightway clarified. Different from the previous work, the prominent flame retardant durability of SR/H-DTMA@Mn in many extreme environment can be maintained via the protection action of hydrophobic structure. The detailed analysis on char residues of SR composites can explain the effective flame retardant mechanism in view of chemical composition and microscopic morphology. Moreover, the mechanical strength and thermal properties of SR composites are ideal and accommodated that are greatly required in the real-life application. To sum up, the desirable balance for comprehensive performance can be realized by introducing the mono-component flame retardants, which can innately open up the innovation for meeting the requirements of SR materials in more fields. • Mono-component and Mn-doped flame retardants were fabricated for SR. • SR/28 phr H-DTMA@Mn can gain 32.4% LOI value and UL‐94 V‐0 rating. • PHRR and THR reduction of SR/28 phr H-DTMA@Mn are 42.3% and 34.7%. • Excellent balance among comprehensive properties of SR composites can be achieved. • Multi-channel synergistic flame retardant mechanism is preliminarily deduced. [ABSTRACT FROM AUTHOR]