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991.
992.
Chen Sun Wen‐Li He Mei‐Jun Liu Wen‐Jing Pan Lin‐Feng Dong Guang Chen Guo‐Dong Liu Xiao‐Wu Lei 《化学:亚洲杂志》2020,15(19):3050-3058
Recently, low‐dimensional organic‐inorganic hybrid metal halide perovskites acting as single‐component white‐light emitting materials have attracted extensive attention, but most studies concentrate on hybrid lead perovskites. Herein, we present two isomorphic zero‐dimensional (0D) hybrid cadmium perovskites, (HMEDA)CdX4 (HMEDA=hexamethylenediamine, X=Cl ( 1 ), Br ( 2 )), which contain isolated [CdX4]2? anions separated by [HMEDA]2+ cations. Under UV light excitation, both compounds display broadband bluish white‐light emission (515 nm for 1 and 445 nm for 2 ) covering the entire visible light spectrum with sufficient photophysical stabilities. Remarkably, compound 2 shows a high color rendering index (CRI) of 83 enabling it as a promising candidate for single‐component WLED applications. Based on the temperature‐dependent, powder‐dependent and time‐resolved PL measurements as well as other detailed studies, the broadband light emissions are attributed to self‐trapped excitons stemming from the strong electron‐phonon coupling. 相似文献
993.
Developing efficient powder catalysts for hydrogen evolution reaction (HER) in the acidic electrolyte is significant for hydrogen generation in the proton exchange membrane (PEM) water electrolysis technique. Herein, we demonstrated an efficient catalyst for HER in the acid media based on the graphene supported ruthenium telluride nanoparticles (RuTe2/Gr). The catalysts were easily fabricated by a facile microwave irradiation/thermal annealing approach, and orthorhombic RuTe2 crystals were found anchored over the graphene surface. The defective structure was demonstrated in the aberration‐corrected transmission electron microscopy images for RuTe2 crystals and graphene support. This catalyst required an overpotential of 72 mV to drive 10 mA cm?2 for HER when loading on the inert glass carbon electrode; Excellent catalytic stability in acidic media was also observed to offer 10 mA cm?2 for 10 hours. The Volmer‐Tafel mechanism was indicated on RuTe2/Gr catalyst by Tafel slope of 33 mV dec?1, similar to that of Pt/C catalysts. The high catalytic performance of RuTe2/Gr could be attributed to its high dispersion on the graphene surface, high electrical conductivity and low charge transfer resistance. This powder catalyst has potential application in the PEM water electrolysis technique because of its low cost and high stability. 相似文献
994.
Shao-Dong Li Feng Su Miao-Li Zhu Li-Ping Lu 《Acta Crystallographica. Section C, Structural Chemistry》2020,76(9):863-868
A new coordination polymer (CP), namely, poly[[diaquatris[μ2‐1,4‐bis(1H‐imidazol‐1‐yl)benzene]bis[μ6‐4‐(2,4‐dicarboxylatophenoxy)phthalato]tetracobalt(II)] hexahydrate], {[Co4(C16H6O9)2(C12H10N4)3(H2O)2]·6H2O}n, has been synthesized by solvothermal reaction. The CP was fully characterized by IR spectroscopy, elemental analysis, thermogravimetric analysis, and powder and single‐crystal X‐ray diffraction. It presents a three‐dimensional (3D) structure based on tetranuclear CoII secondary building units (SBUs) with a tfz‐d net and point symbol (43)2(46·618·84). The 4‐(2,4‐dicarboxyphenoxy)phthalic acid (H4dcppa) ligands are completely deprotonated and link {Co4(COO)4}4? SBUs into two‐dimensional (2D) layers. Furthermore, adjacent layers are connected by 1,4‐bis(1H‐imidazol‐1‐yl)benzene (bib) ligands, giving rise to a 3D supramolecular architecture. Interestingly, there are numerous elliptical cavities in the CP where isolated unique discrete hexameric water clusters have been observed. The results of thermogravimetric and magnetic analyses are described in detail. 相似文献
995.
Feng Zhanxia Chang Zongyu Deng Chao Zhao Lin Chen Jia Zhang Jiakun Zheng Zhongqiang 《Nonlinear dynamics》2022,108(3):2007-2022
Nonlinear Dynamics - Wave glider is an unmanned surface vehicle that can directly convert wave energy into forward propulsion and fulfill long-term marine monitoring. A previous study suggested... 相似文献
996.
Yue Chen Mengjing Lv Juan Zhou Ke Huang Yubo Sun Juntao Feng 《Molecules (Basel, Switzerland)》2022,27(5)
The Valsa canker caused by Valsa mali seriously harmed the production of East Asian apples and caused very significant economic losses. Considering the chemical residues and the improvement of people’s awareness of environmental protection, there is a need for screening new green pesticides for the control of Valsa canker. Therefore, we conducted systematic evaluations on the antifungal activity of wood tar. In this research, the effective concentration (EC50) of six strains of V. mali to wood tar was determined, and the EC50 ranged from 69.54 to 92.81 μg/mL. After treatment with wood tar, the hyphae of V. mali broke, swelled, and deformed; the permeability of the cell membrane increased; and the activity of pectinase reduced. Moreover, the expression levels of five genes related to pectinase also decreased significantly. In addition, the activities of phenylalanine ammonia lyase (PAL) and peroxidase (POD) of apple leaves treated with wood tar also increased. On detached apple branches, wood tar also showed therapeutic and protective activities. In the 2016–2019 field experiments, wood tar also showed good efficacy against Valsa canker and promoted the formation of callus. (In the experiments from 2016 to 2019, it can be seen that the control effect of 50% wood tar and 100% wood tar in the field is above 75% and promoted the formation of callus.) This study is the first to report the bidirectional efficacy of wood tar against Valsa mali and for trunk wound healing. The above results evidenced that wood tar has great potential to be developed as a natural alternative to commercial fungicides for the management of apple Valsa canker. 相似文献
997.
Two-dimensional metal-organic frameworks (2D MOFs) inherently consisting of metal entities and ligands are promising single-atom catalysts (SACs) for electrocatalytic chemical reactions. Three 2D Fe-MOFs with NH, O, and S ligands were designed using density functional theory calculations, and their feasibility as SACs for hydrogen evolution reaction (HER), oxygen evolution reaction (OER), and oxygen reduction reaction (ORR) was investigated. The NH, O, and S ligands can be used to control electronic structures and catalysis performance in 2D Fe-MOF monolayers by tuning charge redistribution. The results confirm the Sabatier principle, which states that an ideal catalyst should provide reasonable adsorption energies for all reaction species. The 2D Fe-MOF nanomaterials may render highly-efficient HER, OER, and ORR by tuning the ligands. Therefore, we believe that this study will serve as a guide for developing of 2D MOF-based SACs for water splitting, fuel cells, and metal-air batteries. 相似文献
998.
999.
新型成膜电解液添加剂亚硫酸丁烯酯的电化学行为 总被引:2,自引:0,他引:2
合成制备了一种新的环状亚硫酸酯类有机溶剂——亚硫酸丁烯酯(BS). 量子化学计算结果表明, 亚硫酸丁烯酯有机溶剂分子的总能、LUMO值比碳酸丙烯酯有机溶剂的低, 具有较强的得电子能力, 不易被氧化. 其作为添加剂与碳酸丙烯酯(PC)混合应用于锂离子电池中, 可有效地抑制PC在石墨电极中的共插入, 能显著改善循环性能. 相似文献
1000.
LIN Feng LI Ying YANG Wen-kui LIANG Bing MU Ying SUN Ye LI Wei LUO Gui-min 《高等学校化学研究》2007,23(1):58-63
IntroductionReactive oxygen species(ROS) are known to de-stroy biomacromolecules and cause cell injury[1]. Un-der normal circumstances, there is a balance betweenthe production of ROS and their destruction. Many dis-eases, such as brain ischemia, tumor, v… 相似文献