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991.
Gang Wang Ke Ye Jiaqi Shao Yingying Zhang Kai Zhu Kui Cheng Jun Yan Guiling Wang Dianxue Cao 《International Journal of Hydrogen Energy》2018,43(19):9316-9325
Porous Ni2P nanoflower supported on nickel foam (Ni2P@Ni foam) electrodes are synthesized via a simple hydrothermal growth strategy accompanied with further phosphating treatment. The prepared electrodes are characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), energy dispersive X-ray spectroscopy (EDX) and transmission electron microscopy (TEM). Electro-catalytic performances towards urea electro-oxidation are tested by cyclic voltammetry (CV), chronoamperometry (CA) coupled with electrochemical impedance spectroscopy (EIS). By phosphating Ni(OH)2 precursor, the final obtained Ni2P@Ni foam electrode presents a porous Ni2P nanoflower structure within abundant porosity, and so exposes a large amount of electro-catalytic active sites and electronic transmission channels to accelerate the interfacial reaction. Compared with Ni(OH)2@Ni foam precursor, the Ni2P@Ni foam catalyst exhibits more excellent electro-catalytic activity as well as lower onset oxidation potential. Remarkably, the Ni2P@Ni foam catalyst reaches a peak current density of 750 mA cm?2 with an onset oxidation potential of 0.24 V (vs. Ag/AgCl) accompanied by an excellent stability in 0.60 M urea with 5.00 M KOH solutions. Benefiting from the unique porous nanosheet structure, the as-synthesized Ni2P@Ni foam catalyst performs a highly enhanced catalytic behavior for alkaline urea electro-oxidation, indicating that the material can be hopefully applied in direct urea fuel cells. 相似文献
992.
Mine Water and the Environment - In March 2019, a well was drilled in the north of the Dashu pyrite mining area in southwest China to extract shale gas from below the pyritic layer. This well... 相似文献
993.
For design of a geosynthetic-reinforced pile-supported (GRPS) embankment over soft soil, the methods used to calculate strains in geosynthetic reinforcement at a vertical stress were mostly developed based on a plane-strain or two-dimensional (2-D) condition or a strip between two pile caps. These 2-D-based methods cannot accurately predict the strain of geosynthetic reinforcement under a three-dimensional (3-D) condition. In this paper, a series of numerical models were established to compare the maximum strains and vertical deflections (also called sags) of geosynthetic reinforcement under the 2-D and 3-D conditions, considering the following influence factors: soil support, cap shape and pattern, and a cushion layer between cap and reinforcement. The numerical results show that the maximum strain in the geosynthetic reinforcement decreased with an increase of the modulus of subgrade reaction. The 2-D model underestimated the maximum strain and sag in the geosynthetic reinforcement as compared with the 3-D model. The cap shape and pattern had significant influences on the maximum strains in the geosynthetic reinforcements. An empirical method involving the geometric factors of cap shape and pattern, and the soil support was developed to convert the calculated strains of geosynthetic reinforcement in piled embankments under the 2-D condition to those under the 3-D condition and verified through a comparison with the results in the literature. 相似文献
994.
995.
Significant improvement for the functional properties of konjac glucomannan based on phase separation
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Qing Huang Honghe Ge Weiping Jin Bakht R. Shah Shuxin Ye Ying Hu Bin Li Yijie Chen 《International Journal of Food Science & Technology》2016,51(11):2396-2405
Konjac glucomannan (KGM) serves as a stabiliser due to its high molecular weight and viscosity. However, these properties limit its addition in food products, especially in drinks. The main aim of this study was to improve the functional properties of KGM by a green and effective method, that is phase separation. It was found that increasing temperature accelerated phase separation of KGM/gum arabic mixture. KGM‐rich phase was characterised and its physical properties were investigated by different methods. Crystal property showed no significant changes after phase separation. Nevertheless, rheological properties indicated that the viscosities of samples after phase separation (FKGM) decreased dramatically. Their emulsifying capacities also improved. Moreover, the differences in molecular rearrangement at the oil–water interface were also studied by using interfacial rheology. These results suggested that FKGM with low viscosity had better interfacial properties, and thus may have potential applications as food ingredients. 相似文献
996.
V. P. Martsenyuk I. Ye. Andrushchak N. M. Gandzyuk 《Cybernetics and Systems Analysis》2013,49(3):347-352
This paper presents a method for constructing exponential estimates in a compartmental system with distributed delays on the basis of the Hale–Lunel inequality and its application. The practical importance of this study is illustrated by a pharmacokinetic model from anesthesiology. 相似文献
997.
The problem of fuzzy clustering of multivariate observations is considered and a group of Kohonen neural network adaptive self-learning algorithms is proposed. The algorithms allow for online possibilistic fuzzy clustering with variable fuzziness levels and are computationally simple and flexible when operating under a priori uncertainty about the nature of data distribution in clusters. 相似文献
998.
Yuyu Wang Shiliang Yu Guojun Ma Songbo Chen Ye Shi Yuhong Yang 《International Journal of Food Science & Technology》2014,49(4):983-989
The proximate composition and amino acid compositions of the muscle of wild and farmed Pseudobagrus ussuriensis were compared. The lipid content of the farmed fish was significantly higher, while moisture content was significantly lower, than those of the wild fish. Pseudobagrus ussuriensis protein has a well‐balanced amino acid composition. The percentages of total amino acids, essential amino acids, nonessential amino acids and delicious amino acids were significantly higher in the wild than those in farmed fish. The ratios of WEAA to WTAA (42.78%–43.02%) and WEAA to WNEAA (85.52%–87.74%) were comparable to the reference values of 40% and above 60% recommended by FAO/WHO. According to the amino acid scores, methionine would have been described as the first limiting amino acid, and Lys had the highest score for the protein in both wild and farmed Pseudobagrus ussuriensis. This study shows that Pseudobagrus ussuriensis under investigation have high nutritional qualities and are good protein resources. 相似文献
999.
对煤矿数据采集系统做一概述,指出系统的研究背景和目标;然后详细阐述了该系统软件的总体设计、需求分析及系统实现过程中的几个关键点;最后给出经过实践验证取得的成果,从而证明该系统的可用性。 相似文献
1000.
陈烨 《湖南工业职业技术学院学报》2012,12(6):45-47
解决中小企业实现持续发展的问题,有助于充分发挥中小企业对经济的促进作用。本文基于湖南省十大重点行业的中小企业调查,从企业内部经营管理着手,探究实现中小企业持续发展管理机制。 相似文献