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81.
N. Z. Hakobyan Z. A. Hovasyan S. S. Hovakimyan A. G. Melkonyan N. A. Pagutyan G. A. Panosyan G. A. Gevorgyan 《Russian Journal of General Chemistry》2020,90(3):385-389
Aminomethylation of 3-methyl-3-ethylpyrrolidin-2,5-dione (ethosuximide) and 3-(4-isopropoxyphenyl)pyrrolidine-2,5-dione (pufemide) with a 25% aqueous formalin solution and alkyl(aryl)amines yielded corresponding N-aminomethyl derivatives. The antioxidant activity of the synthesized compounds and their effect on some parameters of the blood coagulation system were studied. 相似文献
82.
Experimental Mechanics - Background: Experimental modelling techniques are still rare for composite structures under complex thermal environments. Objective: In this paper, by taking a... 相似文献
83.
Yue Liu Yuxiang Wang Haoran Cheng Dr. Zheng Ma Dr. Qian Li Prof. Gang Wang Prof. Daocheng Pan Prof. Limin Wang Prof. Jun Ming 《Chemistry (Weinheim an der Bergstrasse, Germany)》2022,28(25):e202104463
Inorganic cesium lead halide perovskite nanocrystals are candidates for lighting and display materials due to their outstanding optoelectronic properties. However, the dissolution issue of perovskite nanocrystals in polar solvents remains a challenge for practical applications. Herein, we present a newly designed one-step spin-coating strategy to prepare a novel multicolor-tunable CsPbX3 (X=Cl, Br, I) nanocrystal film, where the CsPbX3 precursor solution was formed by dissolving PbO, Cs2CO3, and CH3NH3X into the ionic liquid n-butylammonium butyrate. The as-designed CsPbX3 nanocrystal films show high color purity with a narrow emission width. Also, the blue CsPb(Cl/Br)3 film demonstrates an absolute photoluminescence quantum yields (PLQY) of 15.6 %, which is higher than 11.7 % of green CsPbBr3 and 8.3 % of red CsPb(Br/I)3 film. This study develops an effective approach to preparing CsPbX3 nanocrystal thin films, opening a new avenue to design perovskite nanocrystals-based devices for lighting and display applications. 相似文献
84.
Il’ichev A. N. Bykhovsky M. Ya. Fattakhova Z. T. Shashkin D. P. Korchak V. N. 《Kinetics and Catalysis》2022,63(5):505-514
Kinetics and Catalysis - Samples of (0.5–15)%CoO/CeO2, Co3O4, and CeO2 have been studied in the oxidation of CO to CO2 in a CO+O2+H2 mixture in a range of 40–340°C. The highest... 相似文献
85.
Zhengcheng Wang Shangyan Zhou Wei Liao Qian Zhou Meida Chen Jin Long Prof. Qingmei Wang 《Chemistry (Weinheim an der Bergstrasse, Germany)》2022,28(66):e202201987
The designs of efficient and inexpensive Pt-based catalysts for methanol oxidation reaction (MOR) are essential to boost the commercialization of direct methanol fuel cells. Here, the highly catalytic performance PtFe alloys supported on multiwalled carbon nanotubes (MWCNTs) decorating nitrogen-doped carbon (NC) have been successfully prepared via co-engineering of the surface composition and electronic structure. The Pt1Fe3@NC/MWCNTs catalyst with moderate Fe3+ feeding content (0.86 mA/mgPt) exhibits 2.26-fold enhancement in MOR mass activity compared to pristine Pt/C catalyst (0.38 mA/mgPt). Furthermore, the CO oxidation initial potential of Pt1Fe3@NC/MWCNTs catalyst is lower relative to Pt/C catalyst (0.71 V and 0.80 V). Benefited from the optimal surface compositions, the anti-corrosion ability of MWCNT, strong electron interaction between PtFe alloys and MWCNTs and the N-doped carbon (NC) layer, the Pt1Fe3@NC/MWCNTs catalyst presents an improved MOR performance and anti-CO poisoning ability. This study would open up new perspective for designing efficient electrocatalysts for the DMFCs field. 相似文献
86.
87.
Tianyue Qian Huacheng Zhang Xingya Li Jue Hou Chen Zhao Qinfen Gu Huanting Wang 《Angewandte Chemie (International ed. in English)》2020,59(31):13051-13056
1D nanochannels modified with responsive molecules are fabricated to replicate gating functionalities of biological ion channels, but gating effects are usually weak because small molecular gates cannot efficiently block the large channels in the closed states. Now, 3D metal–organic framework (MOF) sub‐nanochannels (SNCs) confined with azobenzene (AZO) molecules achieve efficient light‐gating functionalities. The 3D MOFSNCs consisting of a MOF UiO66 with ca. 9–12 Å cavities connected by ca. 6 Å triangular windows work as angstrom‐scale ion channels, while confined AZO within the MOF cavities function as light‐driven molecular gates to efficiently regulate the ion flux. The AZO‐MOFSNCs show good cyclic gating performance and high on–off ratios up to 17.8, an order of magnitude higher than ratios observed in conventional 1D AZO‐modified nanochannels (1.3–1.5). This work provides a strategy to develop highly efficient switchable ion channels based on 3D porous MOFs and small responsive molecules. 相似文献
88.
Long‐Zhang Dong Lei Zhang Jiang Liu Qing Huang Meng Lu Wen‐Xin Ji Ya‐Qian Lan 《Angewandte Chemie (International ed. in English)》2020,59(7):2659-2663
A series of stable heterometallic Fe2M cluster‐based MOFs ( NNU‐31‐M , M=Co, Ni, Zn) photocatalysts are presented. They can achieve the overall conversion of CO2 and H2O into HCOOH and O2 without the assistance of additional sacrificial agent and photosensitizer. The heterometallic cluster units and photosensitive ligands excited by visible light generate separated electrons and holes. Then, low‐valent metal M accepts electrons to reduce CO2, and high‐valent Fe uses holes to oxidize H2O. This is the first MOF photocatalyst system to finish artificial photosynthetic full reaction. It is noted that NNU‐31‐Zn exhibits the highest HCOOH yield of 26.3 μmol g?1 h?1 (selectivity of ca. 100 %). Furthermore, the DFT calculations based on crystal structures demonstrate the photocatalytic reaction mechanism. This work proposes a new strategy for how to design crystalline photocatalyst to realize artificial photosynthetic overall reaction. 相似文献
89.
本文采用导模法生长技术,成功制备了高质量掺Si氧化镓(β-Ga2O3)单晶,掺杂浓度为2×1018 cm-3.晶体呈现淡蓝色,通过劳厄衍射、阴极荧光(CL)及拉曼测试对晶体的基本性质进行了表征,结果表明晶体质量良好.紫外透过光谱证明该晶体的禁带宽度约为4.71 eV.此外,在剥离衬底上,采用电子束蒸发、光刻和显影技术制备了垂直结构的肖特基二极管,平均击穿场强EAva为2.1 MV/cm,导通电阻3 mΩ·cm2,展示了优异性能. 相似文献
90.
Wang C. Cheng S. Y. Zhao W. W. Yang X. N. Zhou K. Z. Tian J. J. Jiang D. F. Ma P. H. 《Crystallography Reports》2020,65(7):1156-1160
Crystallography Reports - This paper reports on the supramolecular self-assembly of cyclopentano cucurbit[5]uril (CyP5Q[5]), L-phenylalanine (L-Phe), and cadmium ions. The crystal structure is... 相似文献