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Viscosity and structure relationship with equimolar substitution of CaO with MgO in the CaO–MgO–Al_(2)O_(3)–SiO_(2)slag melts

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International Journal of Minerals,Metallurgy and Materials 2025年第1期32卷 70-79页

作者： Yong Hou shuo Zhang Jie Dang jia guo Hanghang Zhou Xuewei Lü College of Materials Science and Engineering Chongqing UniversityChongqing 400044China Chongqing Key Laboratory of Vanadium-Titanium Metallurgy and New Materials Chongqing UniversityChongqing 400044China

Currently,the Al_(2)O_(3)content in the high-alumina slag systems within blast furnaces is generally limited to 16wt%–18.5wt%,making it challenging to overcome this *** most studies that concentrated on managing the MgO/Al_(2)O_(3)ratio or basicity,this paper explored the effect of equimolar substitution of MgO for CaO on the viscosity and structure of a high-alumina CaO-MgO-Al_(2)O_(3)-SiO_(2)slag system,providing theoretical guidance and data to facilitate the application of high-alumina *** results revealed that the viscosity first decreased and then increased with higher MgO substitution,reaching a minimum at 15mol%MgO *** transform infrared spectroscopy(FTIR)results found that the depths of the troughs representing[SiO_(4)]tetrahedra,[AlO_(4)]tetrahedra,and Si-O-Al bending became progressively deeper with increased MgO *** of the Raman spectra showed that the average number of bridging oxygens per Si atom and the X_(Q^(3))/X_(Q^(2))(X_(Q^(i))is the molar fraction of Q^(i) unit,and i is the number of bridging oxygens in a[SiO_(4)]tetrahedral unit)ratio increased from 2.30 and 1.02 to 2.52 and 2.14,respectively,indicating a progressive polymerization of the silicate structure.X-ray photoelectron spectroscopy(XPS)results highlighted that non-bridging oxygen content decreased from 77.97mol% to 63.41mol% with increasing MgO concentration,whereas bridging oxygen and free oxygen contents *** analysis demonstrated a gradual increase in the polymerization degree of the tetrahedral structure with the increase in MgO ***,bond strength is another important factor affecting the slag *** occurrence of a viscosity minimum can be attributed to the complex evolution of bond strengths of non-bridging oxygens generated during depolymerization of the[SiO_(4)]and[AlO_(4)]tetrahedral structures by CaO and MgO.

关键词： aluminosilicate viscosity structure spectroscopy

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十字型鸭翼子弹药控制系统研究

北京理工大学学报 2018年第2期38卷 179-182页

作者：何光林张嘉朔郭亚超杨姣颖张崭北京理工大学机电学院北京100081

为解决子弹药的杀伤效能低的问题,提出了一种十字型鸭式子弹药并对其进行控制系统的分析与设计.针对子弹药不断旋转摆动的问题,分析了子弹药控制力的产生原理,提出一种周期平均控制力的方法,建立了旋转摆动子弹药数学模型.为验证子弹药... 详细信息

为解决子弹药的杀伤效能低的问题,提出了一种十字型鸭式子弹药并对其进行控制系统的分析与设计.针对子弹药不断旋转摆动的问题,分析了子弹药控制力的产生原理,提出一种周期平均控制力的方法,建立了旋转摆动子弹药数学模型.为验证子弹药的飞行稳定性,应用Matlab软件进行了无控飞行轨迹仿真,得出子弹药水平位移为450m,攻角变化在0.4°以内,满足稳定性要求.由于子弹药控制通道间具有较强耦合作用,设计了一种特殊的前馈补偿法来对子弹药进行解耦,设计了PID控制器对子弹药控制效果进行了仿真,结果表明解耦后控制通道间的耦合效果基本消失.

关键词：自寻的子弹药飞行轨迹仿真周期平均控制力 PID控制前置反馈补偿解耦

Multiple Tin Compounds Modified Carbon Fibers to Construct Heterogeneous Interfaces for Corrosion Prevention and Electromagnetic Wave Absorption

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Nano-Micro Letters 2025年第1期17卷 507-527页

作者： Zhiqiang guo Di Lan Zirui jia Zhenguo Gao Xuetao Shi Mukun He Hua guo Guanglei Wu Pengfei Yin College of Science Sichuan Agricultural UniversityYa’an 625014People’s Republic of China School of Materials Science and Engineering Hubei University of Automotive TechnologyShiyan 442002People’s Republic of China Institute of Materials for Energy and Environment State Key Laboratory of Bio‑Fibers and Eco‑TextilesCollege of Materials Science and EngineeringQingdao UniversityQingdao 266071People’s Republic of China Shaanxi Key Laboratory of Macromolecular Science and Technology School of Chemistry and Chemical EngineeringNorthwestern Polytechnical UniversityXi’anShaanxi 710072People’s Republic of China

Currently,the demand for electromagnetic wave(EMW)absorbing materials with specific functions and capable of withstanding harsh environments is becoming increasingly ***-component interface engineering is considered an effective means to achieve high-efficiency EMW ***,interface modulation engineering has not been fully discussed and has great potential in the field of EMW *** this study,multi-component tin compound fiber composites based on carbon fiber(CF)substrate were prepared by electrospinning,hydrothermal synthesis,and high-temperature thermal *** utilizing the different properties of different substances,rich heterogeneous interfaces are *** effectively promotes charge transfer and enhances interfacial polarization and conduction *** prepared SnS/SnS_(2)/SnO_(2)/CF composites with abundant heterogeneous interfaces have and exhibit excellent EMW absorption properties at a loading of 50 wt%in epoxy *** minimum reflection loss(RL)is−46.74 dB and the maximum effective absorption bandwidth is 5.28 ***,SnS/SnS_(2)/SnO_(2)/CF epoxy composite coatings exhibited long-term corrosion resistance on Q235 steel ***,this study provides an effective strategy for the design of high-efficiency EMW absorbing materials in complex and harsh environments.

关键词： Electrostatic spinning Component regulation Heterogeneous interfaces Electromagnetic wave absorption Corrosion protection

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公安院校大学语文教学改革刍议

辽宁警专学报 2012年第5期14卷 102-105页

作者：姜振华贾硕果重庆警察学院侦查系重庆401331

在公务员考试改革的大背景下,公安院校唯一的出路就是内强素质、主动求变。而相比公务员考试大纲中对语文能力的要求,目前公安院校大学语文课程存在教学内容单一、教学手段单调、教学目标缺乏针对性的弊端。因此必须在教材编写上、教学... 详细信息

在公务员考试改革的大背景下,公安院校唯一的出路就是内强素质、主动求变。而相比公务员考试大纲中对语文能力的要求,目前公安院校大学语文课程存在教学内容单一、教学手段单调、教学目标缺乏针对性的弊端。因此必须在教材编写上、教学设计上和考试考察上进行改革,将公务员考试的要求融入大学语文的教学之中。

关键词：公务员考试公安院校大学语文改革

Deciphering the role of ultra-low-loaded rhodium in NiFe-MIL-53 for superior oxygen evolution reaction

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Journal of Energy Chemistry 2025年第1期100卷 77-86页

作者： Jinzhi jia Jinhua Zhang Kailu guo Lanyue Zhang Gening Du Hao You Junfeng Huang Mudong Tu Hua Li Yong Peng Wei Dou Cailing Xu State Key Laboratory of Applied Organic Chemistry College of Chemistry and Chemical Engineering School of Materials and Energy Lanzhou University College of Chemistry and Chemical Engineering Luoyang Normal University

Designing highly active and stable electrocatalysts of oxygen evolution reaction （OER） is one of the crucial *** this study,a novel OER electrocatalyst,NiFe-MIL-53 modified with ultra-low rhodium（Rh@NiFe-MIL-53）,is successfully prepared via the hydrothermal ***-situ Raman spectroscopy and electrochemical impedance spectroscopy reveal that the doped Rh accelerates the phase transformation of NiFe-MIL-53 and the in-situ formed Rh@NiFeOOH is the actual active *** importantly,the enhanced reversibility of electrochemical reconstruction between NiFeOOH and NiFe（OH）2after doping Rh is beneficial for improving the electrochemical stability of the catalyst.X-ray photoelectron spectroscopy spectra show the strong electronic interaction between single-atom Rh and Ni/Fe in Rh@***,theoretical calculations confirm that the integration of single-atom Rh into the NiFeOOH successfully reduces the band gap,regulates the d-band center （εd）,accelerates the charge transfer,and optimizes the adsorption behavior of oxygen-containing intermediates,thereby lowering the energy barrier of rate-determining ***,the optimized Rh@NiFe-MIL-53 exhibits excellent OER activity （240 mV） with a small Tafel slope of 48.2 mV dec-1and long-term durability (over1270 h at 10 m A cm-2and 110 h at 200 mA cm-2).This work presents a new perspective on designing highly efficient OER electrocatalysts.

关键词： NiFe-MIL-53 Rh Electrochemical reconstruction Catalytic mechanism Oxygen evolution reaction

Decreased levels of phosphorylated synuclein in plasma are correlated with poststroke cognitive impairment

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Neural Regeneration Research 2025年第9期20卷 2598-2610页

作者： Yi Wang Yuning Li Yakun Gu Wei Ma Yuying Guan Mengyuan guo Qianqian Shao Xunming Ji jia Liu Department of Clinical Laboratory Beijing Bo’ai HospitalChina Rehabilitation Research CenterCapital Medical UniversityBeijingChina Beijing Institute of Brain Disorders Laboratory of Brain DisordersMinistry of Science and TechnologyCollaborative Innovation Center for Brain DisordersBeijing Advanced Innovation Center for Big Data-based Precision MedicineCapital Medical UniversityBeijingChina Department of Neurosurgery Xuanwu HospitalCapital Medical UniversityBeijingChina

Poststro ke cognitive impairment is a major secondary effect of ischemic stroke in many patients;however,few options are available for the early diagnosis and treatment of this *** aims of this study were to(1)determine the specific relationship between hypoxic andα-synuclein during the occur of poststroke cognitive impairment and(2)assess whether the serum phosphorylatedα-synuclein level can be used as a biomarker for poststro ke cognitive *** found that the phosphorylatedα-synuclein level was significantly increased and showed pathological aggregation around the cerebral infa rct area in a mouse model of ischemic *** addition,neuronalα-synuclein phosphorylation and aggregation were observed in the brain tissue of mice subjected to chronic hypoxia,suggesting that hypoxia is the underlying cause ofα-synuclein-mediated pathology in the brains of mice with ischemic *** phosphorylatedα-synuclein levels in patients with ischemic stroke were significantly lower than those in healt hy subjects,and were positively correlated with cognition levels in patients with ischemic ***,a decrease in serum high-density lipoprotein levels in stroke patie nts was significantly correlated with a decrease in phosphorylatedα-synuclein *** ischemic stroke mice did not show significant cognitive impairment or disrupted lipid metabolism 14 days after injury,some of them exhibited decreased cognitive function and reduced phosphorylatedα-synuclein *** together,our results suggest that serum phosphorylatedα-synuclein is a potential biomarker for poststroke cognitive impairment.

关键词： biomarker high-density lipoprotein ischemic stroke phosphorylatedα-synuclein poststroke cognitive impairment

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浅议警官职业院校计算机实践教学改革

重庆电力高等专科学校学报 2009年第2期14卷 56-58页

作者：唐苹贾硕果李振宇重庆警官职业学院侦查系重庆400039

分析警官职业学院计算机实践教学内容中存在教学内容与实战脱节、教学模式不适合等问题,提出增加公安信息化应用教学内容、改革教学模式、突出专业特色、收集公安资讯等改革思路。

关键词：计算机实践教学教学改革

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高温下HMX热分解反应分子动力学模拟

原子与分子物理学报 2025年第2期42卷 105-110页

作者：陈芳贾方硕陈瑶李天浩郭国琦董羚中北大学化学与化工学院太原030051

本文采用ReaxFF-lg反应分子动力学方法研究了奥克托金(HMX)在六种不同温度下的初始反应热分解过程,验证了ReaxFF-lg势函数对HMX体系的适用性,计算了不同温度下HMX体系势能、总物种演化趋势、初始反应产物以及指前因子和活化能.结果表明,... 详细信息

本文采用ReaxFF-lg反应分子动力学方法研究了奥克托金(HMX)在六种不同温度下的初始反应热分解过程,验证了ReaxFF-lg势函数对HMX体系的适用性,计算了不同温度下HMX体系势能、总物种演化趋势、初始反应产物以及指前因子和活化能.结果表明,HMX热分解过程主要有三种初始分解机理:N-NO_(2)键的断裂,HONO的解离和主环上C-N键的断裂,计算得到的初始分解阶段活化能Ea和指前因子ln(A),与实验值相吻合.

关键词： HMX 反应分子动力学(RMD) ReaxFF-lg 热分解温度

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硫掺杂氧化钨电催化剂的析氢性能研究

陕西科技大学学报 2025年第1期43卷 107-114,125页

作者：贾鹏飞杨军李硕郑璐瑶张煜国陕西科技大学材料科学与工程学院陕西西安710021

通过硫掺杂来改善氧化钨(WO_(3))电催化剂活性不足和反应动力学缓慢的问题.采用二次煅烧法成功合成了硫掺杂氧化钨(S-WO_(3))电催化剂,并系统地研究了掺杂浓度对其形貌、结构和电化学性能的影响.结果表明,硫掺入氧化钨后能够在引入氧缺... 详细信息

通过硫掺杂来改善氧化钨(WO_(3))电催化剂活性不足和反应动力学缓慢的问题.采用二次煅烧法成功合成了硫掺杂氧化钨(S-WO_(3))电催化剂,并系统地研究了掺杂浓度对其形貌、结构和电化学性能的影响.结果表明,硫掺入氧化钨后能够在引入氧缺陷的同时调控电子结构,显著提高了氧化钨的电催化活性.使用硫粉量为0.11 g的S-WO_(3)-1催化剂具有最佳的硫掺杂浓度.为了实现10 mA cm^(-2)的电流密度仅仅需要161 mV过电位,并且能够持续长达30000 s的析氢过程,显示出优异的催化活性和循环稳定性.本研究为开发掺杂型高效析氢电催化剂提供了新途径.

关键词：电催化剂析氢反应氧化钨硫掺杂电子结构