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排序方式: 共有6203条查询结果,搜索用时 15 毫秒
101.
Bo Jiang Hui Song Yunqing Kang Shengyao Wang Qi Wang Xin Zhou Kenya Kani Yanna Guo Jinhua Ye Hexing Li Yoshio Sakka Joel Henzie Yamauchi Yusuke 《Chemical science》2020,11(3):791
Generating high surface area mesoporous transition metal boride is interesting because the incorporation of boron atoms generates lattice distortions that lead to the formation of amorphous metal boride with unique properties in catalysis. Here we report the first synthesis of mesoporous cobalt boron amorphous alloy colloidal particles using a soft template-directed assembly approach. Dual reducing agents are used to precisely control the chemical reduction process of mesoporous cobalt boron nanospheres. The Earth-abundance of cobalt boride combined with the high surface area and mesoporous nanoarchitecture enables solar-energy efficient photothermal conversion of CO2 into CO compared to non-porous cobalt boron alloys and commercial cobalt catalysts.Generating high surface area mesoporous transition metal boride is challenging but interesting because incorporation of boron atoms can generate lattice distortion to form amorphous metal boride which has unique properties in catalysis. 相似文献
102.
On the Criteria of Instability for Electrochemical Systems 总被引:7,自引:0,他引:7
Both cyclic-voltammetry-based and impedance-based experimental criteria that have been developed recently for the oscillatory electrochemical systems are critically appraised with two typical categories of oscillators.Consistent conclusions can be drawn by the two criteria for the category of oscillators that involve the coupling of charge transfer mainly with surface steps(e.g.ad-and desorption)such as in the electrooxidation of C1 organic molecules.Whereas,impedance-based criterion is not applicable to the category of oscillators that involve the coupling of charge transfer mainly with mass transfer(e.g.diffusion and convection) such as in the Fe(CN)6^3- reduction accompanying periodic hydrogen evolution.The reason is that the negative impedance cannot include the feedback information of convection mass transfer induced by the hydrogen evolution.However,both positive and negative nonlinear feedbacks,i.e., the diffusion-limited depletion and convection-enhanced replenishment of the Fe(CN)6^3- surface concentration,that coexist between the bistability,i.e.,Fe(CN)6^3- reduction with and without hydrogen evolution at lower and higher potential sides respectively,are all reflected in the crossed cyclic voltammogram(CCV).It can be concluded that the voltammetry-based criterion(in time domain)is more intuitive,less time-consuming and has a wider range of applications than the impedancebased one (in frequency domain). 相似文献
103.
In this paper, a separation method of the inorganic anions including I–, NO
2
–
, NO
3
–
, IO
3
–
and SCN– on the reversed-phase ion-pair chromatography with direct UV detection has been developed, and the limits of detection of these inorganic anions were determined. The effects of the organic modifier volume fraction and concentration of the ion-pair reagent on the retention of inorganic anions were discussed. 相似文献
104.
Xiong Ya Zou Xiao-Hua Wu Jian-Zhong Ji Liang-Nian Li Run-Hua Zhou Jian-Ying Yu Kai-Bei 《Transition Metal Chemistry》1999,24(3):263-267
A new polypyridyl ligand, MCP {MCP = 2-(3-chlorophenyl)imidazo[4,5-f]1,10-phenanthroline} and its ruthenium(II) complex, [Ru(bpy)2(MCP)](ClO4)2· 0.5MeCN (bpy = 2,2-bipyridine), have been synthesized and characterized. The structure of the complex was determined by single crystal X-ray diffraction techniques. The MCP ligand is essentially planar and the stacking interactions between the ligands were observed in the crystal. [Ru(bpy)2(MCP)]2+ can strongly bind to Calf thymus DNA through intercalation of MCP ligand. The Cl substitute group has no significant effect on the spectral properties and DNA-binding behaviour of the complex. 相似文献
105.
Diao Hongyue Deng Ansheng Cui Hui Liu Xin Zou Li 《Fuzzy Optimization and Decision Making》2022,21(1):45-69
Fuzzy Optimization and Decision Making - Linguistic information processing exists in multi-criteria decision making, and linguistic truth-valued lattice implication algebra (LTV-LIA) has definite... 相似文献
106.
Analytical solutions of the lattice Boltzmann BGK model 总被引:1,自引:0,他引:1
Analytical solutions of the two-dimensional triangular and square lattice Boltzmann BGK models have been obtained for the plane Poiseuille flow and the plane Couette flow. The analytical solutions are written in terms of the characteristic velocity of the flow, the single relaxation time , and the lattice spacing. The analytic solutions are the exact representation of these two flows without any approximation. Using the analytical solution, it is shown that in Poiseuille flow the bounce-back boundary condition introduces an error of first order in the lattice spacing. The boundary condition used by Kadanoffet al. in lattice gas automata to simulate Poiseuille flow is also considered for the triangular lattice Boltzmann BGK model. An analytical solution is obtained and used to show that the boundary condition introduces an error of second order in the lattice spacing. 相似文献
107.
108.
109.
Weaver M Arisaka K Roberts D Slater W Briere RA Cheu E Harris DA Roodman A Schwingenheuer B Wah YW Winstein B Winston R Barker AR Swallow EC Bock GJ Coleman R Crisler M Enagonia J Ford R Hsiung YB Jensen DA McFarland KS Ramberg E Tschirhart R Collins EM Gollin GD Nakaya T Yamanaka T Gu P Haas P Hogan WP Kim SK Matthews JN Myung SS Schnetzer S Somalwar SV Thomson GB Zou Y 《Physical review letters》1994,72(24):3758-3761
110.