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971.
The CO2 reduction reaction (CRR) represents a promising route for the clean utilization of renewable resources. But mass-transfer limitations seriously hinder the forward step. Enhancing the surface hydrophobicity by using polymers has been proved to be one of the most efficient strategies. However, as macromolecular organics, polymers on the surface hinder the transfer of charge carriers from catalysts to reactants. Herein, we describe an in-situ surface fluorination strategy to enhance the surface hydrophobicity of TiO2 without a barrier layer of organics, thus facilitating the mass transfer of CO2 to catalysts and charge transfer. With less obstruction to charge transfer, a higher CO2, and lower H+ surface concentration, the photocatalytic CRR generation rate of methanol (CH3OH) is greatly enhanced to up to 247.15 μmol g−1 h−1. Furthermore, we investigated the overall defects; enhancing the surface hydrophobicity of catalysts provides a general and reliable method to improve the competitiveness of CRR.  相似文献   
972.
973.
Journal of Radioanalytical and Nuclear Chemistry - Soil radon anomaly is a common phenomenon in karst areas. In this paper, the geochemical behavior of radium (Ra) in the process of carbonate rock...  相似文献   
974.
Li  Mian  Yang  Er  Shen  Zhenzhou  Lv  Xizhi  Ni  Yongxin  Yang  Jishan  Ma  Li 《Journal of Radioanalytical and Nuclear Chemistry》2022,331(5):2285-2293
Journal of Radioanalytical and Nuclear Chemistry - Differences in the net soil loss and apportionment of wind from water erosion on hillslopes were analyzed and evaluated quantitatively through...  相似文献   
975.
Journal of Radioanalytical and Nuclear Chemistry - The waste LiCl–Li2O oxide reduction salt was solidified and transformed into sodalite by the spark plasma sintering method. Compared with...  相似文献   
976.
Kim  S. V.  Baikenov  M. I.  Ainabaev  A. A.  Ibishev  K. S.  Meiramov  M. G.  Grigorieva  V. P.  Ma  F. 《High Energy Chemistry》2022,56(3):201-207
High Energy Chemistry - Optimal conditions for producing ultrafine iron powder by combining the processes of electrolysis and high-voltage discharge have been determined. It has been established...  相似文献   
977.
卢昂  陈壮志  巫秀美  马秀英  赵昱 《化学通报》2022,85(10):1261-1266
应用定量构效关系(Quantitative structure activity relationship, QSAR)研究阐明黄酮类化合物(Flavonoid compounds, FCs)的子结构指纹(Substructure fingerprint)与1,1-二苯基-2-三硝基苯肼(1,1-Diphenyl-2-picrylhydrazyl, DPPH)自由基清除能力之间的关系,从而指导高效抗氧化物质的设计和发现。在PubMed数据库中收集77个具有明确抗氧化活性的黄酮类化合物,而在ChEMBL数据库中收集86个无抗DPPH活性的黄酮类化合物。这163个黄酮类化合物的子结构指纹由PubChem系统生成,然后通过卡方检验筛选出与黄酮类化合物的抗氧化活性显著相关的分子指纹,最后通过判别分析建立预测QSAR模型,并采用回代法和交叉验证法对已建立的模型进行准确性和稳健性的验证。结果表明,黄酮类化合物抗DPPH自由基活性与ESSSR环的计数、简单相邻原子的类型和简单的SMARTS模式等因素有关。此外,所建立的QSAR模型能较好地预测黄酮类化合物的DPPH自由基清除活性,可用于评价候选抗氧化剂的潜力。  相似文献   
978.
Journal of Thermal Analysis and Calorimetry - A new set of iron-uranium phosphate glasses containing (1–20) UO2.67. (10–20) Fe2O3. (55–68) P2O5 (mass/%) were melted adequately....  相似文献   
979.
Adding insulating polymers to conjugated polymers is an efficient strategy to tailor their mechanical properties for flexible organic electronics. In this work, we selected two insulating polymers as additives for high-performance photoactive layers and investigated the mechanical and photovoltaic properties in organic solar cells (OSCs). The insulating polymers were found to reduce the electron mobilities in the photoactive layers, and hence the power conversion efficiencies were significantly decreased. More importantly, we found that the insulating polymers exhibited negative effect on the mechanical properties of the photoactive layers, with reduced Young's modulus and low crack onset strains. Further studies revealed that the insulating polymers had poor miscibility with the photoactive layers, providing large domains and more cavities in blend thin films, which act as negative effect for the tensile test. The studies indicate that rational selection of insulating polymers, especially enhancing the non-covalent interaction with the photoactive layers, will be critically important for the stretchable OSCs.  相似文献   
980.
Organic solar cells (OSCs) harvesting indoor light are highly promising for emerging technologies, such as internet of things. Herein, the photovoltaic performance of PTB7-Th:PC71BM solar cells constructed using “optimized (with 1,8-diiodooctane (DIO))” and “non-optimized (without DIO)” processing conditions are compared for indoor and outdoor applications. We find that in comparison to the “optimized” solar cell, the “non-optimized” solar cell is less efficient under simulated solar light illumination (100 mW cm−2, spectral range 350–1100 nm), owing to significant bimolecular charge carrier recombination losses. However, under simulated indoor illumination (3.28 mW cm−2, spectral range 400–700 nm), bimolecular recombination losses are effective suppressed, thus the power conversion efficiency of the solar cell without DIO was increased to 14.7 %, higher than that of the solar cell with DIO (14.2 %). These results suggest that the common strategy used to optimize the OSCs could be undesired for indoor OSCs. We demonstrate that the efforts for realizing the desired “morphology” of the active layer for the outdoor OSCs may be unnecessary for indoor OSCs, allowing us to realize high-efficiency indoor OSCs using a non-halogenated solvent.  相似文献   
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