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991.
《International Journal of Hydrogen Energy》2020,45(35):17649-17661
In this study, the hydrogen generation from the catalytic hydrolysis of the ethylenediamine bisborane (EDAB) was performed. For this purpose, the p(sulfopropyl acrylate potassium salt-co-2-acrylamido-2-methylpropansulfonic acid sodium salt)@Ag(0) (p(SPA-co-AMPS)@Ag) catalyst was prepared. Later the p(SPA-co-AMPS)@Ag containing Ag(0) particles with nanodimensions was used as catalyst in EDAB hydrolysis. Our study is the first in the literature from this aspect, and investigated in detail the effect of catalyst amount, reactive concentration, temperature and dry or swollen nature of the catalyst on the EDAB hydrolysis. At the end of the reaction series, the hydrolysis reaction of EDAB with p(SPA-co-AMPS)@Ag catalyst was determined to have activation energy (Ea) of 43.24 kJmol-1. Additionally, the turn over frequency (TOF) was 0.560 mol H2(mol Ag(0).min)−1 at 30 °C. The p(SPA-co-AMPS)@Ag catalyst had perfect reusability with 95% of initial activity after the 5th use for the hydrogen generation from EDAB. 相似文献
992.
《Journal of the European Ceramic Society》2020,40(13):4556-4561
In this study, silica based slurries for stereolithographic printing of glass structures are developed and characterized. Stereolithography has the potential to print complex structures with high resolution. Therefore, acrylate based photocurable slurries have been developed and their viscosities are examined as a function of the solid loading. A critical shear rate can be derived, which must not be exceeded during the printing process. Therefore, rheological characterizations provide important insights into the printing process and the ability to produce samples with precise structures. Other properties such as polymerization time and curability kinetic were investigated with time dependent attenuated total reflection infrared spectroscopy (ATR-IR). Afterwards, the slurries were printed on a commercial printer operating with visible light. For debinding the printed green bodies, the decomposition temperatures were derived from thermogravimetric analysis in order to obtain stable and transparent samples. 相似文献
993.
Berdan Ulas Aykut Caglar Sakir Ylmaz Umit Ecer Yonca Yilmaz Tekin Sahan Hilal Kivrak 《国际能源研究杂志》2019,43(15):8985-9000
In this study, multiwall carbon nanotube (MCNT)‐supported Pd (Pd/MWCNT) catalysts are prepared by using NaBH4 reduction method. In order to maximize the oxidation and reduction of H2SO4, synthesis conditions (Pd ratio, molar ratio of NaBH4/K2PdCl4, volume of deionized water, and duration of agitation) are optimized by using response surface methodology (RSM). The optimum synthesis conditions are determined as 58.2% of Pd by weight, 154.6 molar ratio of NaBH4 to K2PdCl4, 19.48 mL of deionized water, and 186.16 min of agitation duration. The effect of electrochemical measurement conditions on the oxidation kinetics of Pd/MWCNT is also investigated by RSM. The optimum electrochemical measurement conditions are found as 10 μL of catalyst mixture, 90°C of H2SO4 solution, and 5.5 M H2SO4. The Pd/MWCNT, Pd50Ag50/MWCNT, and Pd65.6Ag33.6Cr0.80/MWCNT catalysts prepared under optimized conditions are characterized by using X‐ray diffraction, transmission electron microscopy, N2 adsorption‐desorption, and inductively coupled plasma mass spectrometry. The crystallite sizes of these catalysts are found as 4.85, 5.66, and 5.26 nm for Pd/MWCNT, Pd50Ag50/MWCNT, and Pd65.6Ag33.6Cr0.80/MWCNT catalysts, respectively. Isotherms of all these catalysts are found to be similar to Type V isotherms with H3 hysteresis loop. The average particle size of Pd50Ag50/MWCNT and Pd65.6Ag33.6Cr0.80/MWCNT catalysts are determined as 5.2 and 9.2 nm, respectively. Electrochemical performance of as‐prepared catalysts is evaluated by using cyclic voltammetry and chronoamperometry. The formic acid electrooxidation (FAEO) activities are found as 18.9, 27.8, and 51.6 mA/cm2 for Pd/MWCNT, Pd50Ag50/MWCNT, and Pd65.6Ag33.6Cr0.80/MWCNT, respectively. Pd65.6Ag33.6Cr0.80/MWCNT shows the highest activity and stability. Optimization of synthesis conditions and electrochemical measurement parameters allow us to obtain very good electrochemical activity and stability for FAEO reaction compared with anode catalysts in the literature. 相似文献
994.
以钛酸丁酯、无水乙醇、硝酸银等为原料,通过溶胶-凝胶法制备了不同Ag掺杂含量的TiO2纳米晶粉体,用X射线衍射(XRD)、扫描电子显微镜(SEM)和透射电子显微镜(TEM)检测分析了粉体的晶型转化、微观形貌和晶粒尺寸,用光致发光光谱(PL)表征材料的光电性能。结果表明,Ag掺杂后的TiO2纳米晶粉体的锐钛矿相比未掺杂Ag样品的含量有所增多,当Ag掺杂量为1%和3%时,锐钛矿的相对含量约为65%;随着Ag掺杂量的增加,锐钛矿晶粒尺寸逐渐减小;由TEM图像可知,Ag颗粒较为均匀地弥散在TiO2纳米晶粉体中;由PL荧光检测结果可知,Ag掺杂TiO2纳米晶粉体的荧光强度比未掺杂的TiO2纳米晶粉体的低。试验结果表明,Ag颗粒较为均匀地弥散在TiO2纳米晶粉体中,有利于在锐钛矿界(表)面形成Ti-O-Ag的键合,有效阻止锐钛矿向金红石的转变,同时抑制锐钛矿TiO2纳米晶粒的增长,Ag颗粒与TiO2纳米晶粉体接触形成肖特基势垒,加速光生电子由TiO2向Ag颗粒传输,减小光生电子与空穴的复合几率,从而提高TiO2纳米晶粉体的光电性能。 相似文献
995.
Nasrin Oroujzadeh Elham Delpazir Zahra Shariatinia 《Particulate Science and Technology》2019,37(4):423-429
Using ultrasonic top-to-down method, nanoparticles of two N-nicotinyl phosphoric triamides: C5H4NC(O)NHP(O)R, R?=?4-CH3-NC5H10 (1), (CH3)3CNH2 (2) were prepared for the first time and characterized by 31P, 13C, 1H NMR, FTIR, scanning electron microscopy, energy dispersive X-ray. The average particle size of 1 and 2 were 60–70 and 40–50?nm, respectively, and the morphology was spherical for 1 and rod for 2. Solid state (powder) antibacterial effect of these compounds and two other similar reported ones, in their macro- and nanosizes, were evaluated with colony counting method on one Gram-positive (Staphylococcus aureus) and one Gram-negative (Escherichia coli) bacteria in Brain–Heart infusion culture medium. Results showed that all the macro- and nanosized compounds, except macrosized 1, were antibacterial and all nanoscaled ones had stronger antibacterial activity than their macroscaled analogues. The most effect of the particle size was observed for 1: by decreasing the particle sizes, the antibacterial activity state of 1 was changed from inactive (for macro) to potent (for nano). 相似文献
996.
997.
《International Journal of Hydrogen Energy》2019,44(4):2407-2416
In this study, Iron doped Zinc oxide (FeZnO) nanoparticles (NPs) were synthesized and coated on carbon paper electrode. The NPs and NPs coated electrode physicochemical, antimicrobial, antibiofilm traits and MFC performances were investigated. The characterization results depicted that FeZnO NPs were hexagonal rod shape with hexagonal phase structure in size of 90–100 nm have 59 m2/g surface area. Antibiofilm results indicates concentration of 5 mg/L of NPs shows 39 and 42% inhibition for Lysinibacillus Sphaericus and Bacillus safensis. The antibacterial assay confirmed that test organism was more resistant against NPs and coated electrode. Impedance analysis of NPs coated anode shown decreased anodic charge transfer resistance. The MFC results confirmed that power density was increased for NPs coated electrode (134.7 mW/m2) as compared to uncoated electrode. Cyclic Voltammetry analysis reported that exoelectrogenesis was promoted by NPs. The NPs coated and bare electrode COD removal efficiency were found to be 72.8 and 63.8%. 相似文献
998.
999.
1000.