Spin-state regulating of cobalt assisted by iron doping and coordination for enhanced oxygen evolution reaction

Customizing catalysts from the electronic structure, such as spin state, is an effective but challenging strategy for oxygen evolution reaction (OER). Herein, an ultrafine Co–Fe material highly dispersed on nitrogen carbide matrix is fabricated by coordination polymer and self-templating method to scrutinize the impact of spin state of Co on OER through Fe doping. The optimized catalyst shows boosted OER performance, which only requires overpotential of 333 mV at 10 mA cm^?2, outperforming other control samples and commercial RuO₂. The elevated local spin states of Co by Fe doping lead to charge transfer acceleration and fast generation of oxygenated intermediates, which is proved to account for the OER elevation. In addition, the long-term stability of Co–Fe material is guaranteed by the strong coordination of Co/Fe to the melamine-formaldehyde resin, which is used to adsorb metal ions, contributing to the high dispersion of active sites during the OER process.     

Novel inorganic precursors [Co4.32Zn1.68(HCO2)18(C2H8N)6]/SiO2 and Co4.32Zn1.68(HCO2)18(C2H8N)6]/Al2O3 for Fischer–Tropsch synthesis

The silica- and alumina-supported Co–Zn catalysts were synthesized by thermal decomposition of new inorganic precursors [Co_4.32Zn_1.68(HCO₂)₁₈(C₂H₈N)₆]/SiO₂ or Al₂O₃. A novel coordination polymer formulated as [Co_4.32Zn_1.68(HCO₂)₁₈(C₂H₈N)₆] (1) was prepared using the solvothermal technique and characterized by elemental analysis, FT-infrared spectroscopy. Thermal stability of the complex 1 was investigated by thermogravimetric analysis and differential scanning calorimetry, and its structure was determined by single-crystal X-ray diffraction. Characterization of catalysts was carried out using powder X-ray diffraction (XRD), scanning electron microscopy (SEM), and BET specific surface area. The catalysts were evaluated for Fischer–Tropsch synthesis (FTS) in the temperature range 200–300 °C. The results revealed that the synthesized catalysts have higher selectivity to the desired products at 260 °C. The performance of the catalysts was compared to those of catalysts constructed via impregnation method and the fabricated catalysts show higher activity and selectivity than the reference catalysts.     

纳米抛光碳化硅压力对相变影响的分子动力学模拟

为了研究纳米抛光碳化硅时压力变化对表面的影响规律,建立了金刚石磨粒纳米抛光碳化硅的分子动力学模型,数值模拟了纳米尺度下的碳化硅抛光过程,具体分析了抛光压力线性增大过程中的配位数为1至6的原子数量的变化规律,揭示了线性改变抛光压力对被加工表面相变的影响规律,仿真结果表明:压力是诱导碳化硅相变的主要因素,当抛光压力增大时,发生相变的原子数增多,碳化硅的相变深度增加,其中配位数为1、2和4的原子数减少,配位数为3、5和6的原子数增多。     

From Flood Land to New Urban Area: Water Adaptation History and Visions for Daodi Flood Land in the West of Beijing

Daodi Flood Land, located in Mentougou District of Beijing, is a relatively separate flood land in the lower reaches and on the east of Yonding River. This largest landscape character area in the west of Beijing along the river illustrates the history of human–water interaction and discloses the trends and problems of rural urbanization. Focusing on Daodi Flood Land, this paper expands the research on adaptation by introducing basic concepts and research framework, and reviews the research trends from spatial, temporal, and participant aspects. Considering the typical characters of the study area, this research employed participatory approaches, such as mapping and problem and solution trees, due to the lack of continuous and accurate data. Basing on literature review and field investigation on issues of floods, agricultural irrigation, and water resource utilization, water adaptive development visions for the study area were proposed from perspectives of landscape and culture. Finally, the paper further analyzes the structural relations between adaptation problems, natural and social systems, passive and active adaptations, and planned and unplanned adaptations, with the aim to provide reference for relevant studies and applications of adaptation approaches in other cases.     

Novel mixed ligand complexes of Co(II), Ni(II), Cu(II), and Zn(II) with 1,10-phenanthroline and acesulfame. Synthesis,structural analysis and hydrogen adsorption study

Four novel metal organic framework (MOF) structures containing acesulfame (ace) and 1,10-phenanthroline (phen) ligands of Co²⁺, Ni²⁺, Cu²⁺ and Zn²⁺ metal cations were synthesized. The crystal structure analysis of three compounds (1, 2, and 3) was also performed. The structural formula for complex 4 is proposed based on spectroscopic and thermal analysis data. It has been determined that structures 1, 2, and 4 are in a distorted octahedral geometry. It has been suggested that the charge balance of the coordination sphere with 2+ is provided by two monoanionic ace ligands located outside the coordination sphere as counter-ion. In structure 3, there are two Cu^II metal cations, two phen ligands coordinated as bidentate to each metal cation and ace ligand that provides monoanionic-monodentate coordination. The Cu²⁺ cation has distorted bipyramidal geometry. The maximum hydrogen gas adsorption has been found 1.4575 mL/g (0.046 wt%) for the Ni complex.     

倾斜摄影测量技术在古建筑测绘中的运用研究——以郴州市汝城县朱氏宗祠建筑测绘为例

为测试倾斜摄影测量技术路线,并通过实际项目的应用,解决传统古建筑建模过程中存在的时间成本高、难以还原复杂场景等问题。按照倾斜摄影技术的技术路线,进行朱氏宗祠建筑测绘试验,并通过基于altizure软件建立三维模型来展现倾斜摄影测量技术流程。验证无人机倾斜摄影应用于古建筑三维建模的可行性和可操作性。     

物联网本体存储数据可撤销加密仿真研究

针对物联网密钥不可随机拆分与撤销,本体存储数据容易遭到外界入侵,导致用户隐私信息泄露,提出物联网本体存储数据可撤销加密方法。根据数据可撤销加密的理论确定双线性映射函数,通过加密撤销的困难假设构建了物联网本体存储数据可撤销模型。对存储数据进行可撤销运算,采用了周期更新思想,将用户密钥属性、用户身份以及时间进行划分,并根据访问树的节点数据对用户存储数据进行加密计算。通过主要密钥随机拆分撤销运算,根据结果对存储数据可撤销加密进行安全认证。仿真结果表明,采用可撤销加密方法能够实现物联网密钥的随机拆分,缩短用户密钥更新周期,数据安全性更高。     

矿业可持续发展的灰色动态评价

本文建立了基于灰色系统理论的矿业可持续发展动态评价模型，提出了以发展趋势和协调性评价为基本内涵的动态评价思路，并以我国有色金属矿业为例进行了矿业可持续发展动态评价实证研究。所用的方法及建模思路对其他类似产业乃至整个国民经济系统的评价也是适用的。     

一种射影变换的图形图像纠正原理

由于各种因素的影响,地形图会发生不规则变形,因此,必须对其进行纠正.为此提出了一种射影变换纠正法,叙述了其纠正方法和纠正原理,并总结了其优点.     

浅谈测绘成果档案的信息化管理

大力推广应用信息技术和开发利用信息资源,是我省在“十一五”期间围绕“海峡西岸建设”提出的一项重要任务,而测绘工作涉及社会经济发展的各个领域,因此要针对目前在档案管理中存在的问题,大力推进测绘成果档案的信息化管理,保证测绘成果档案更好的为产业经济服务。