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11.
The issues of hydrogen generation and storage have hindered the widespread use and commercialization of hydrogen fuel cell vehicles.It is thus highly attractive,but the design and development of highly active non-noble-metal catalysts for on-demand hydrogen release from alkaline NaBH4 solution under mild conditions remains a key challenge.Herein,we describe the use of CoP nanowire array integrated on a Ti mesh (CoP NA/Ti) as a three-dimensional (3D) monolithic catalyst for efficient hydrolytic dehydrogenation of NaBH4 in basic solutions.The CoP NA/Ti works as an on/off switch for on-demand hydrogen generation at a rate of 6,500 mL/(min.g) and a low activation energy of 41 kJ/mol.It is highly robust for repeated usage after recycling,without sacrificing catalytic performance.Remarkably,this catalyst also performs efficiently for the hydrolysis of NH3BH3. 相似文献
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Cage and ladder structures of silsesquioxanes characterized by UV-MALDI-TOF mass spectrometry 总被引:1,自引:0,他引:1
The molar mass distribution of SSO in the first generation derived from the hydrolytic condensation of two trialkoxysilanes, [3- (Methacryloxy) propyl] trimethoxysilane (MPMS) and vinyltrimethoxysilane (VMS), are determined by UV-MALDI-TOF MS. The comparisons of theoretical masses with experimental masses are calculated using the proposed compounds, which are assigned to formulas Tn (OH)_m, T_n (OMe)_y or T_n(OH)_x(OMe)_y[T=RSiO_(1.5-(x+y)/2n), R=——(CH_2)_3OOCCH(CH_3)CH_2 and——CHCH_2]. Both the proposed cage and ladder structures of SSO derived from similar sol-gel process of monomers are illustrated. The causes for the difference in structures between SSO_M and SSO_v is discussed as well. 相似文献
14.
水解聚马来酸酐的阻垢分散性能 总被引:1,自引:0,他引:1
静态阻垢法研究了水解聚马来酸酐(HPMA)的阻垢性能,失重法研究了HPMA的分散性能,采用正交组合实验考查了几个主要因素对HPMA的阻垢性能和分散性能的影响.结果表明:HPMA的加入量为8.0mg.L-1时有最佳阻垢效果,阻垢率为68.7%;HPMA的浓度为10.0mg.L-1时,其平均分散性能达到6.30×10-2mg.cm-2h-1,加入渗透剂T后效果更好,在渗透剂T为1.0mg.L-1时,平均分散能力达到了6.56×10-2mg.cm-2h-1. 相似文献
15.
啤酒废水处理工程设计及运行分析(一) 总被引:5,自引:0,他引:5
华润啤有限公司排放的啤酒废水采用内循环水解化-好氧化工艺进行处理,处理后出水水质指标COD-72.5mg/L,BOD=11.0mg/L,SS=8.4mg/L,达到GB8978-1996国家污水综合排放标准。内循环水解酸化-好氧工艺处理啤废水的工程实践和运行分析表明,本工艺具有占地面积小,设备简单,出水水了,剩余污泥不等优点。 相似文献
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MQ silicone resins, which represent a broad range of hydrolytic condensation products of monofunctional silane (M) and tetrafunctional silane (Q), were synthesized by reaction of water glass with hexamethyldisiloxane. The optimum reaction time and the optimal reaction temperature is 30 min and 30–40°C, respectively. Concentrated hydrochloric acid is the best one among those catalysts tested. In large-scale experiments (420–1680 mL), the favorable feeding order is catalyst first, and then water glass, the mixture of hexamethyldisiloxane and ethanol last and most MQ silicone resin was observed. The structure of MQ silicone resin was characterized by FT-IR and GPC spectra. The MQ silicone resin shows narrow molecular weight distribution and the number average molecular weight of MQ silicone resin is 2917. The silicone pressure sensitive adhesive prepared from as-synthesized MQ resin has good tack (29#) and 180° peel adhesion (5.630N/20 mm). © 2012 Wiley Periodicals, Inc. J Appl Polym Sci, 2012 相似文献
18.
Hanna Harrysson Birgitta Swolin Michael Axelsson Ingrid Undeland 《International Journal of Food Science & Technology》2020,55(6):2462-2471
Whole body saline-perfused rainbow trout (Oncorhynchus mykiss) was ice-stored for 4 weeks and compared with unwashed/washed minces from unbled and bled trout in terms of rancid odour, peroxide value (PV), thiobarbituric acid reactive substances (TBARS) and redness loss. Muscle from saline-perfused fish, which had 72% less total haem, was deficient in rancid odour during the whole storage, while bled (54% less haem) and unbled samples developed rancid odour already after ~4 and 2 days; higher intensity without bleeding. PV/TBARS also developed in the order unbled > bled > perfused samples; however, PV/TBARS were not as completely prevented as rancid odour after perfusion. Saline washing (3 × 3 volumes) of unbled mince removed 84% haem and yielded the second most stable sample while saline washing (1 × 1 volumes) destabilised unbled mince, despite 64% haem removal. Concurrent antioxidant removal during washing of minces obviously counteracted the effect of blood removal and washing fish mince with small volumes of solution should be used with great care. 相似文献
19.
A series of sulfonated copolyimides (SPIs) with hydrophilic segment length of 20–60 based on 4,4′‐sulfide‐bis(naphthalic anhydride) (SBNA) have been successfully synthesized to improve hydrolytic stability and proton conductivity. The SPI membranes were cast from their m‐cresol solutions, and they were characterized by determining the water uptake, water swelling ratio, mechanical properties, hydrolytic stability, oxidative stability, and proton conductivity. It was found that the water uptake of SPI membranes was low and decreased as the hydrophilic segment length increased, which led to good dimensional stability. In addition, the SPI membranes with low ion‐exchange capacity (IEC) value displayed excellent hydrolytic stability and retained good mechanical properties even after harsh hydrolysis testing, in which the block SPI with hydrophilic segment length of 40 had the best hydrolytic stability, while those with high IEC value showed an apparent decrease. All of the block SPI membranes show better conductivity than the random ones at the temperature range from 30 to 70°C. Interestingly, the proton conductivities of random SPI membranes were higher than that of corresponding block ones at 90°C. The block SPI with hydrophilic segment length of 40 gave the highest proton conductivity as the temperature increased among the block SPIs. © 2014 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2015 , 132, 41501. 相似文献
20.
开发区工业废水处理厂提标改造工程实例 总被引:1,自引:1,他引:0
针对开发区工业废水水质复杂,可生化性较差的特点,通过采取增加水解酸化段,将传统AO工艺改造为MBBR工艺,增建臭氧氧化-BAF深度处理工艺等措施对园区污水厂进行提标改造。改造后运行结果显示,出水CODCr、NH3-N、TN质量浓度分别为38~45、0.5~7.5、10~14 mg/L,稳定达到GB 18918—2002《城镇污水处理厂污染物排放标准》一级A标准的要求。主要介绍了改造后的工艺流程,给出了主要构筑物的设计参数及设备配置。 相似文献