Reductive demetalation of manganese corroles:The substituent effect

The reductive demetalation of manganese corroles was investigated in CH2Cl2/HCl （aqueous） solvent by using SnCl2 as reducing agent. It was found that the demetalation yields depend on the substituents of corrole macrocycle significantly. Electron- rich manganese corrole undergoes reductive demetalation more easily than electron-deficient ones. The isolated reductive demetalation yield of manganese 5,10,15-tris（phenyl）corrole in present system is moderate （46%）. As for electron-deficient Mn（Ⅲ） 5,10,15-tris（pentafluorophenyl）corrole, the acid-induced demetalation in HOAc-HESO4 （V/V = 3：1） is preferable with an isolated yield of 67%.

基于DEMATEL的企业集团信用风险评估指标体系研究

近年来,一些企业集团相继出现信用风险,给银行、投资人及社会带来巨大损失。而企业集团历来是商业银行最重要的信贷客户资源,如何科学的评估集团客户的信用风险,对商业银行的风险管理至关重要。信用风险评估的关键在指标体系的构建,因此本文通过企业集团的关联交易情况、公司内部治理水平及其他常用的风险指标,构成了企业集团信用风险的评估指标体系。通过DEMATEL方法,得到了指标的权重,发现公司内部治理和关联交易情况等指标对企业集团信用风险影响较大。分析指标权重结果,以期为商业银行对集团客户做信用风险评估时,提供有效的参考。

企业网络舆情安全管理能力模型建构——基于涌现利用的研究视角

为了分析企业网络舆情安全管理能力要素之间的相互作用关系和结构属性,提出了一种基于涌现理论并综合运用AHP和DEMETAL方法分析企业网络舆情安全管理能力的分析路径。首先,在现有网络舆情和安全管理研究成果的基础上,充分参考学者和行业专家的意见,建立企业网络舆情安全管理能力概念模型和构成要素集;其次,针对传统DEMETAL方法的不足,构建了结合AHP改进的DEMETAL方法;最终通过问卷调研建立要素间影响关系判断矩阵,通过计算要素中心度和原因度来确定要素之间影响关系。结果表明,所用方法可以用来分析企业网络舆情安全管理能力并建构相关结构模型。

Recycle Demetallating Process for Hydrocarbonaceous Feedstocks

The development and research on the recycle demetallating process are introduced. It shows the recycle demetallating process is effective on removing metal elements in heavy crude oil, especially with regard to calcium, through commercial application in delayed coking unit. Finally, the ash content in petroleum coke can be decreased to less than 0.5%, which complies with the IB coke standard. At the same time, the recycle demetallating process is an environmentally friendly technique, which has little effect on production quality and equipment corrosion.

The Adsorption Properties of the Sorbents Based on Nanofibrous Carbon

The results of research on the adsorption characteristics of materials based on fibrous carbon (CNF) are considered in this paper. It is shown that changing the conditions and procedure of CNF modifying namely specific adsorption surface, volume of the pore space, and parameters of the pore structure it became possible ultimately to vary in a wide range the adsorption characteristics of obtained materials.

Atomically dispersed Zn-Co-N-C catalyst boosting efficient and robust oxygen reduction catalysis in acid via stabilizing Co-N bonds

Transition metal supported N-doped carbon(M-N-C)catalysts for oxygen reduction reaction(ORR)are viewed as the promising candidate to replace Pt-group metal(PGM)for proton exchange membrane fuel cells(PEMFCs).However,the stability of M-N-C is extremely challenging due to the demetalation,H_(2)O_(2)attack,etc.in the strongly oxidative conditions of PEMFCs.In this study,we demonstrate the universal effect of Zn on promoting the stability of atomically dispersed M-Nx/C(M=Co,Fe,Mn)catalysts and the enhancement mechanism is unveiled for the first time.The best-performing dual-metal-site Zn-Co-N-C catalyst exhibits a high half-wave potential(E1/2)value of 0.81 V vs.reversible hydrogen electrode(RHE)in acid and outstanding durability with no activity decay after 15,000 accelerated degradation test(ADT)cycles at 60℃,surpassing most reported Co-based PGM-free catalysts in acid media.For comparison,the Co-N-C in the absence of Zn suffers from a rapid degradation after ADT due to the demetalation and higher H_(2)O_(2)yield.X-ray adsorption spectroscopy(XAS)and density functional theory(DFT)calculations suggest the more negative formation energy(by 1.2 eV)and increased charge transfer of Zn-Co dual-site structure compared to Co-N-C could strength the Co-N bonds against the demetalation and the optimized d-band center accounts for the improved ORR kinetics.

基于DEMATEL的科研数据共享关键影响因素识别与分析

把握影响科研数据共享的关键因素,有利于推动科研数据开放与共享,促进科研数据发挥更大的作用。运用扎根理论法系统地梳理目前国内外学者提出和发现的科研数据共享影响因素,并通过复杂系统DEMATEL模型构建科研数据共享影响因素的关系矩阵。经计算与分析识别出了13个影响科研数据共享的关键因素,其中包括5个关键驱动因素和8个核心问题因素。我国应制定由上到下的科研数据管理政策和标准化制度,满足不同主体的利益诉求,建立协同工作机制,并通过支持和引导打造科研数据共享生态体系。

The facile synthesis of 5-formylporphyrin

A facile synthetic route of 5-formylporphyrin（2） has been developed.Using pyrrole and pivaldehyde as the starting materials,2 was obtained through several facile reactions.The synthetic route is easy to perform and can be scaled up,which gives the compound a better application perspective.