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91.
Lijuan Li Bingdong Li Liwei Feng Xiaoqiu Zhang Yuqian Zhang Qiannan Zhao Guifu Zuo Xianguang Meng 《Molecules (Basel, Switzerland)》2021,26(13)
In this work, Au-modified F-TiO2 is developed as a simple and efficient photocatalyst for H2O2 production under ultraviolet light. The Au/F-TiO2 photocatalyst avoids the necessity of adding fluoride into the reaction medium for enhancing H2O2 synthesis, as in a pure TiO2 reaction system. The F− modification inhibits the H2O2 decomposition through the formation of the ≡Ti–F complex. Au is an active cocatalyst for photocatalytic H2O2 production. We compared the activity of TiO2 with F− modification and without F− modification in the presence of Au, and found that the H2O2 production rate over Au/F-TiO2 reaches four times that of Au/TiO2. In situ electron spin resonance studies have shown that H2O2 is produced by stepwise single-electron oxygen reduction on the Au/F-TiO2 photocatalyst. 相似文献
92.
A pure calcium borate Ca2[B2O4(OH)2]·0.5H2O has been synthesized under hydrothermal condition and characterized by XRD, FT-IR and TG as well as by chemical analysis. The molar enthalpy of solution of Ca2[B2O4(OH)2]·0.5H2O in HC1·54.582H2O was determined. From a combination of this result with measured enthalpies of solution of H3BO3 in HC1·54.561H2O and of CaO in (HCl + H3BO3) solution, together with the standard molar enthalpies of formation of CaO(s), H3BO3(s) and H2O(l), the standard molar enthalpy of formation of −(3172.5 ± 2.5) kJ mol−1 of Ca2[B2O4(OH)2]·0.5H2O was obtained. 相似文献
93.
Soo Chool Lee Min Sun Cho Suk Yong Jung Chong Kul Ryu Jae Chang Kim 《Adsorption》2014,20(2-3):331-339
A range of potassium-based alumina sorbents were fabricated by impregnation of alumina with K2CO3 to examine the effects of the structural and textural properties of alumina on the CO2 sorption and regeneration properties. Alumina materials, which were used as supports, were prepared by calcining alumina at various temperatures (300, 600, 950, and 1,200 °C). The CO2 sorption and regeneration properties of these sorbents were examined during multiple tests in a fixed-bed reactor in the presence of 1 vol% CO2 and 9 vol% H2O. The regeneration capacities of the potassium-based alumina sorbents increased with increasing calcination temperature of alumina. The formation of KHCO3 increased with increasing calcination temperature during CO2 sorption, whereas the formation of KAl(CO3)(OH)2, which is an inactive material, decreased. These results is due to the fact that the structure of alumina by the calcination temperature is related directly to the formation of the by-product [KAl(CO3)(OH)2]. The structure of alumina plays an important role in enhancing the regeneration capacity of the potassium-based alumina sorbent. Based on these results, a new potassium-based sorbent using δ-Al2O3 as a support was developed for post-combustion CO2 capture. This sorbent maintained a high CO2 capture capacity of 88 mg CO2/g sorbent after two cycles. In particular, it showed a faster sorption rate than the other potassium-based alumina sorbents examined. 相似文献
94.
ZnO纳米管有序阵列与Cu2O纳米晶核壳结构的光电化学性能及全固态纳米结构太阳电池研究简 总被引:1,自引:0,他引:1
采用电化学方法在铟锡氧化物(ITO)导电玻璃基底上制备了高度有序的ZnO纳米管阵列,然后在ZnO纳米管阵列上电化学沉积Cu2O纳米晶颗粒,获得了一维有序Cu2O/ZnO核壳式纳米阵列结构,通过控制Cu2O纳米晶的沉积电量得到不同厚度的Cu2O壳层,并对该核壳式纳米阵列的形貌和结构进行了分析. 以Cu2O/ZnO一维核壳式纳米阵列结构为光电极组装全固态纳米结构太阳电池,研究了Cu2O壳层厚度对光电极光吸收性能、光电性能以及组装电池光伏性能的影响,优化了电池中对电极材料的喷金厚度. 结果表明,以Cu2O沉积电量为1.5 C的Cu2O/ZnO为光活性层,以4 mA电流下真空镀金20~25 min的铜基底为对电极组装的简易太阳电池最高可获得0.013%的光电转换效率. 相似文献
95.
Chuantian Zuo Prof. Liming Ding 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2017,129(23):6628-6632
A family of perovskite light absorbers (NH4)3Sb2IxBr9−x (0≤x≤9) was prepared. These materials show good solubility in ethanol, a low-cost, hypotoxic, and environmentally friendly solvent. The light absorption of (NH4)3Sb2IxBr9−x films can be tuned by adjusting I and Br content. The absorption onset for (NH4)3Sb2IxBr9−x films changes from 558 nm to 453 nm as x changes from 9 to 0. (NH4)3Sb2I9 single crystals were prepared, exhibiting a hole mobility of 4.8 cm2 V−1 s−1 and an electron mobility of 12.3 cm2 V−1 s−1. (NH4)3Sb2I9 solar cells gave an open-circuit voltage of 1.03 V and a power conversion efficiency of 0.51 %. 相似文献
96.
Dr. Qi Liu Dr. Zhilei Ge Dr. Xiuhai Mao Dr. Guobao Zhou Prof. Xiaolei Zuo Dr. Juwen Shen Dr. Jiye Shi Prof. Jiang Li Prof. Lihua Wang Prof. Xiaoqing Chen Prof. Chunhai Fan 《Angewandte Chemie (International ed. in English)》2018,57(24):7131-7135
Weak ligand–receptor recognition events are often amplified by recruiting multiple regulatory biomolecules to the action site in biological systems. However, signal amplification in in vitro biomimetic systems generally lack the spatiotemporal regulation in vivo. Herein we report a framework nucleic acid (FNA)‐programmed strategy to develop valence‐controlled signal amplifiers with high modularity for ultrasensitive biosensing. We demonstrated that the FNA‐programmed signal amplifiers could recruit nucleic acids, proteins, and inorganic nanoparticles in a stoichiometric manner. The valence‐controlled signal amplifier enhanced the quantification ability of electrochemical biosensors, and enabled ultrasensitive detection of tumor‐relevant circulating free DNA (cfDNA) with sensitivity enhancement of 3–5 orders of magnitude and improved dynamic range. 相似文献
97.
98.
5E教学模式在我国的教学实践及其国外研究进展评析 总被引:1,自引:0,他引:1
5E教学模式在国际科学教学中具有广泛应用,是当今重要的探究教学和概念转变的教学模式,在我国基础教育中也有较多的研究和实践。5E教学模式是一种基于建构主义的“学习环”模式,包括引入、探究、解释、精致和评价5个环节,每个环节都有专门的教学策略。系统地梳理了5E教学模式的起源、内涵及特征,对我国现有的基于5E教学模式的实践案例进行了深入分析,描述5E教学模式在我国的实践应用现状及其存在的问题,提出积极的改进建议,促进我国探究教学的深入推进。通过阐释5E教学模式的发展演变和研究进展,描绘今后的研究方向和内容。 相似文献
99.
100.