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941.
采用磷酸硼对木材进行改性处理,测定了处理后试材的阻燃性、抗流失性、吸湿性、力学性能.研究结果表明,磷酸硼处理后试材,吸药量达到20.47 kg/m3以上时,垂直燃烧实验可达到到F-0级水平;通过灼烧实验,磷酸硼处理的木粉在500℃灼烧时残留率可达到97.997%;此改性剂具有较好阻燃性能和一定的抗流失性,常压下磷酸硼处理的樟子松试件LRV为50.28%;木材顺纹抗压强度平均下降了 8.67%,无明显变化;木材抗弯曲压强度平均下降了 27.95%.但磷酸硼阻燃剂在高湿条件下有一定的吸湿性,使用性能有待改进,并应注意采取防护措施. 相似文献
942.
Characteristics and Rheological Properties of Polysaccharide Nanoparticles from Edible Mushrooms (Flammulina velutipes)
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Wenhang Wang Cong Li Guanhua Du Xiuling Zhang Hongjie Zhang 《Journal of food science》2017,82(3):687-693
Nanotechnology has become relevant in the food‐related industries, and edible mushrooms can be a potential raw material for providing satisfied edible nanomaterial. In this study, by following 3 different pretreatments (hot water or cold alkali or hot alkali) insoluble polysaccharide nanoparticles were prepared from Flammulina velutipes by wet milling and high pressure homogenization and their properties were investigated. The resultant nanoparticles were characterized by SEM, GC‐MS (for its main compositions), FTIR, XRD, and TG. The 1 wt% nanoparticle dispersions presented non‐Newtonian, shear‐thinning fluids with the viscosity in an increasing order for the hot water < cold alkali < hot alkali. Moreover, the dynamical rheological results showed differences of storage (G′) and loss (G″) moduli of these particle dispersions. It was concluded that the Flammulina velutipes‐derived polysaccharides nanoparticles have great potential applications in the food industry, for example, as emulsifiers, reinforcement agents, and bioactive carriers. 相似文献
943.
有机氟改性丙烯酸酯树脂研究新进展 总被引:1,自引:0,他引:1
综述了有机氟改性丙烯酸酯树脂的化学改性制备方法(如常规乳液聚合、核壳乳液聚合和无皂乳液聚合等)及其研究新进展,总结了有机氟改性丙烯酸酯树脂在外墙涂料、防腐防污涂料等领域的应用现状,并展望了该研究领域的发展前景。 相似文献
944.
Fast pyrolysis of the crushed Delonix regia seed was carried out in a semi-batch reactor at a temperature ranging from 400 to 650°C with an objective to produce bio-oil. The effect of temperature to obtain an optimum condition for maximum bio-oil yield and the composition of pyrolysis product were investigated. The maximum bio-oil yield was found to be 48?wt% at pyrolysis temperature of 600°C. The chemical composition of bio-oil obtained at optimum condition was analysed using Fourier-transformed infrared spectroscopy and Gas chromatography–mass spectrometry. The chemical analysis of the biofuel showed the presence of hydrocarbons in major, aldehydes, ketones, amides, nitriles, etc. The composition and fuel characteristics of the pyrolysis oil obtained in this work show that it may potentially be used as a renewable fuel and chemical feedstock. 相似文献
945.
Optimization of dielectric heating parameters in the production of high‐voltage LiNiPO4‐core and carbon‐shell ceramics
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Ahmet Örnek 《Journal of the American Ceramic Society》2017,100(12):5668-5680
Excellent core‐shell morphology and nanoscale high‐voltage LiNiPO4@C cathode materials have been synthesized by a low‐level and long‐time microwave and solvothermal synthesis methodology. The effects of the changing physicochemical parameters on the crystal‐quality and electrochemical properties of the products have been evaluated in relation to the cycling stability. X‐ray diffraction analysis shows that it is possible to synthesize phase‐pure LiNiPO4 material when the reaction parameters are carefully elaborated. High‐resolution transmission electron microscopy analysis reveals a core‐shell morphology with a coating thickness of 6‐8 nm for 30 minutes at 180°C solvothermal temperature and time‐spread microwave energy. This mentioned cathode material exhibits the best electrochemical properties, achieving a discharge capacity of 157 mAh·g?1 at a 0.l C current rate, and shows a remarkable 81% capacity retention at the end of the 80th cycle. 相似文献
946.
Thermodynamic and experimental aspects on chemical looping reforming of ethanol for hydrogen production using a Cu‐based oxygen carrier
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Wenju Wang 《国际能源研究杂志》2014,38(9):1192-1200
An investigation on the chemical looping reforming of ethanol process using Gibbs free energy minimization method was performed. It is found that the temperature, oxygen/ethanol molar ratio (OER), and pressure have pronounced influences on the product yields in chemical looping reforming of ethanol process. The ethanol conversion and H2 yield are 100% and 2.25 mol mol?1 ethanol, respectively, at 700 °C, OER of 1 and 1 atm. The higher temperatures promote H2 and CO production, but the higher pressures and OERs have negative effect on the H2 and CO generation. Favorable operation conditions are 1 atm, 700 °C, and OER = 1. The experimental tests were carried out in a fixed bed using a Cu‐based oxygen carrier prepared by impregnation method. Working at 1 atm, the H2 concentration increased with an increase in temperature; however, it remained approximately with an increase in gas hourly space velocity. The H2/CO molar ratio was between 3 and 5 in the period of 0–30 min at 1 atm and 700 °C. Copyright © 2013 John Wiley & Sons, Ltd. 相似文献
947.
为获取地下水流速和渗透系数等水文地质参数、查清含水层水力联系、查明矿井充水条件,在内蒙古某矿设计实施了化学示踪试验。通过对国内外化学示踪试验资料整理、统计分析,总结出化学示踪剂用量与投放距离、含水层性质的经验关系式,并对本次示踪剂用量做出了评价。同时,对试验中监测点水中均未出现Cl-浓度增高现象进行了科学解释,提出类似含Cl-示踪剂中的某些离子可能被地下岩层特定矿物质吸附时,只要化学试剂中的一种离子能达到试验效果,且具有成本低、易获取等特点,即可选择其作为示踪剂的观点。 相似文献
948.
S. Yolcular 《Energy Sources, Part A: Recovery, Utilization, and Environmental Effects》2016,38(14):2031-2034
Dehydrogenation of organic chemical hydrides has been investigated with catalysts in which the economical Ni was adopted as catalytic component and SiO2 as support. In this work dehydrogenation of methylcyclohexane was performed as organic chemical hydride in a fixed-bed catalytic reactor in the temperature range of 653–713 K, having 5, 10, 15, and 20 wt.% Ni content. 相似文献
949.
A treatment of a chemical reaction network theory is given from the perspective of nonlinear network dynamics, in particular of consensus dynamics. By starting from the complex-balanced assumption, the reaction dynamics governed by mass action kinetics can be rewritten into a form which allows for a very simple derivation of a number of key results in the chemical reaction network theory, and which directly relates to the thermodynamics and port-Hamiltonian formulation of the system. Central in this formulation is the definition of a balanced Laplacian matrix on the graph of chemical complexes together with a resulting fundamental inequality. This immediately leads to the characterisation of the set of equilibria and their stability. Furthermore, the assumption of complex balancedness is revisited from the point of view of Kirchhoff's matrix tree theorem. Both the form of the dynamics and the deduced behaviour are very similar to consensus dynamics, and provide additional perspectives to the latter. Finally, using the classical idea of extending the graph of chemical complexes by a ‘zero’ complex, a complete steady-state stability analysis of mass action kinetics reaction networks with constant inflows and mass action kinetics outflows is given, and a unified framework is provided for structure-preserving model reduction of this important class of open reaction networks. 相似文献
950.
分析了煤化工(煤制油)和风电产业面临的问题,提出了转换角度看待煤化工发展中的制约,把二氧化碳捕集、风电制氢和逆水煤气变换反应相结合,提出煤化工绿色变身的发展思路。 相似文献