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Effect of the Retarder on Initial Hydration and Mechanical Properties of the"one-step"Alkaliactivated Composite Cementitious Materials

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Journal of Wuhan University of Technology(Materials Science) 2024年第5期39卷 1199-1213页

作者： ding rui HE Yue LI Xingchen LI Han TIAN Hao WANG Hongen School of Materials Science and Engineering Jilin Jianzhu UniversityChangchun 130118China Ziyang Urban Construction Investment Group Co. LtdNanchong 637000China Shandong Taihe Urban Construction Development Co. Ltd.Jining 272000China

This paper studied the effects of different retarders on the performance of the"one-step"alkali-activated composite cementitious material(ACCM)which is composed of ground granulated blast slag(GGBS)and fly ash(FA),and analyzed its mechanical properties,hydration mechanism,and retardation *** effects of retarders on the hydration products,mechanical properties,and hydration kinetics of ACCM were investigated using XRD,SEM,FTIR,EDS,and thermoactive *** results showed that Na_(2)B_(4)O_(7)·10H_(2)O(B)delayed the exotherm during the alkali activation process and could effectively delay the setting time of ACCM,but the mechanical properties were slightly *** setting time of ACCM increased with the increase in SG content,but the mechanical properties of ACCM decreased with the increase in SG content.C1_(2)H_(22)O_(11)(CHO)could effectively delay the hydration reaction of ACCM and weakly enhanced the compressive strength.H_(3)PO_(4)(HP)at a concentration of 0.05 mol/L had a certain effect on ACCM retardation,but HP at a concentration of 0.07 and 0.09 mol/L had an effect of promoting the setting and hardening time of ACCM.

关键词： "one-step"alkali-activated composite cementitious materials solid activator hydration mechanism retarder retarding mechanism

Local tetragonal distortion of Pt alloy catalysts for enhanced oxygen reduction reaction efficiency

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Carbon Energy 2024年第7期6卷 41-52页

作者： Xiaoke Li Xiao Duan Kang Hua Yongkang Wu Zhiyan rui rui ding Aidong Li Chen Ouyang Jia Li Ting Li Jianguo Liu National Laboratory of Solid-State Microstructures College of Engineering and Applied Sciencesand Collaborative Innovation Center of Advanced MicrostructuresNanjing UniversityNanjingChina Long-Life Fuel Cell Key Laboratory in Sichuan Province Dongfang Electric(Chengdu)Hydrogen Fuel Cell Technology Co.Ltd.ChengduChina Institute of Energy Power Innovation North China Electric Power UniversityBeijingChina

Platinum-based alloy nanoparticles are the most attractive catalysts for the oxygen reduction reaction at present,but an in-depth understanding of the relationship between their short-range structural information and catalytic performance is still ***,we present a synthetic strategy that uses transition-metal oxide-assisted thermal ***/C catalysts with localized tetragonal distortion were obtained by controlling the thermal diffusion process of transition-metal *** localized structural distortion induced a significant strain effect on the nanoparticle surface,which further shortened the length of the Pt-Pt bond,improved the electronic state of the Pt surface,and enhanced the performance of the ***/C catalysts with special short-range structures achieved excellent mass activity(2.27 Amg_(Pt)^(-1))and specific activity(3.34 A cm^(-2)).In addition,the localized tetragonal distortion-induced surface compression of the Pt skin improved the stability of the *** mass activity decreased by only 13%after 30,000 *** catalyst activity and excellent durability have also been demonstrated in the proton exchange membrane fuel cell *** study provides valuable insights into the development of advanced Pt-based nanocatalysts and paves the way for reducing noble-metal loading and increasing the catalytic activity and catalyst stability.

关键词： electrocatalysts fuel cells local tetragonal distortion oxygen reduction

Research Progress of Environment Friendly Plasticizers for Cellulose Acetate Processing

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Expert Review of Chinese Chemical

Expert Review of Chinese Chemical 2024年第2期2卷 32-36页

作者： rui ding Mengyou Li Chongqing University of Science and Technology Liaoning University of Petroleum and Chemical Technology

Cellulose acetate(CA)is an important cellulose derivative that can undergo thermoplas-tic *** can form stable hydrogen bonds with CA molecular chains,reducing intermolecular and intramolecular interactions,and play an important role in the melting processing of *** recent years,environmentally friendly plasticizers that are natural,non-toxic,odorless,low dissolution,and low migration have received increas-ing attention in plastic *** article reviews the research progress of environ-mentally friendly plasticizers such as natural plasticizers,ionic liquid plasticizers,citrate plasticizers,and polyethylene glycol plasticizers in the processing of cellulose acetate,and looks forward to the application prospects of environmentally friendly plasticizers.

关键词： cellulose acetate environment protection plasticizers

Cleaning of two mirrors in the first mirror unit using radiofrequency capacitively coupled plasma

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Plasma Science and Technology 2024年第9期26卷 165-171页

作者： Chenxue WANG Rong YAN Yuming LIU Su XU Lei MU Wei ZHENG rui ding Junling CHEN Institute of Plasma Physics Chinese Academy of SciencesHefei 230031People’s Republic of China University of Science and Technology of China Hefei 230026People’s Republic of China School of Computer Engineering Anhui Sanlian UniversityHefei 230601People’s Republic of China

First mirror(FM)cleaning,using radio frequency(RF)plasma,has been proposed to recover FM reflectivity in nuclear fusion reactors such as the International Thermonuclear Experimental Reactor(ITER).To investigate the influence of simultaneous cleaning of two mirrors on mirror cleaning efficiency and uniformity,experiments involving single-mirror cleaning and dual-mirror cleaning were conducted using RF capacitively coupled plasma in the *** the test and simultaneous cleaning of two mirrors,the FM and second mirror(SM),both measuring 110 mm×80 mm,were placed inside the first mirror unit(FMU).They were composed of 16 mirror samples,each with a dimension of 27.5 mm×20 *** mirror samples consist of a titanium-zirconium-molybdenum alloy substrate,a 500 nm Mo intermediate layer and a 30 nm Al_(2)O_(3) surface coating as a proxy for Be *** cleaning of a single first mirror(SFM)and the simultaneous cleaning of the FM and SM(DFM and DSM)lasted for 9 h using Ar plasma at a pressure of 1 *** total reflectivity of mirror samples on the DSM did not fully recover and varied with location,with a self-bias of−140 *** a self-bias of−300 V,the total reflectivity of mirror samples on the SFM and DFM was fully *** energy dispersive spectrometer results demonstrated that the Al_(2)O_(3) coating had been completely removed from these mirror ***,the mass loss of each mirror sample on the SFM and DFM before and after cleaning varied depending on its location,with higher mass loss observed for mirror samples located in the corners and lower loss for those in the *** with SM cleaning,the simultaneous cleaning of two mirrors reduced the difference between the highest and lowest mass ***,this mass loss for the mirror samples of the DFM facing the DSM was *** indicated that mirror samples cleaned face to face in the FMU simultaneously could influence each other,highlighting the need for special attention in

关键词： first mirror unit dual-mirror cleaning reflectivity sputtering rate

“功在国家,利在自己”:新中国初期的保本保值储蓄

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安徽史学 2024年第3期 160-168页

作者：丁芮中国社会科学院当代中国研究所北京100009

1950年3月,国家统一财经工作之后,物价趋稳,人民币币值进一步稳定。为消除民众对物价能否长期稳定的顾虑,国家银行在折实储蓄的基础上开办了保本保值储蓄。保本保值储蓄的适宜举办,对民众来说,改善了生活,增强了储蓄兴趣,初步建立了储... 详细信息

1950年3月,国家统一财经工作之后,物价趋稳,人民币币值进一步稳定。为消除民众对物价能否长期稳定的顾虑,国家银行在折实储蓄的基础上开办了保本保值储蓄。保本保值储蓄的适宜举办,对民众来说,改善了生活,增强了储蓄兴趣,初步建立了储蓄习惯;对于国家来说,聚集了社会闲散资金,支援了新中国国家建设。同时,保本保值储蓄的实施,为货币储蓄奠定了基础,也扩大了人民政府的政治影响,体现了新制度的优越性。

关键词：保本保值储蓄新中国初期

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新中国成立前后北京的人民储蓄与社会生活

北京档案 2024年第4期 68-73页

作者：丁芮中国社会科学院当代中国研究所

新中国成立前后,为了平抑物价、安定民众生活,北京陆续举办了折实储蓄、保本保值储蓄等,并以此为基础走上了人民币储蓄的新阶段,开创了新中国的人民储蓄。人民储蓄的创建,平抑了物价,稳固了币值,引导民众养成了储蓄的好习惯,使民众不担... 详细信息

新中国成立前后,为了平抑物价、安定民众生活,北京陆续举办了折实储蓄、保本保值储蓄等,并以此为基础走上了人民币储蓄的新阶段,开创了新中国的人民储蓄。人民储蓄的创建,平抑了物价,稳固了币值,引导民众养成了储蓄的好习惯,使民众不担心物价上涨,保障了民众生活的安定,更使民众初步体会到了新中国生活的幸福感。

关键词：新中国储蓄物价生活

小学初任教师职业自我认同危机的特征与破解路径——基于29名师范大学小学教育专业毕业生一年的追踪研究

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中国教育学刊 2024年第1期 78-83页

作者：丁锐魏巧鹤东北师范大学教育学部吉林长春130024 清华大学附属小学北京100080

初任教师职业自我认同影响教师个体的专业发展,事关教师队伍的稳定性,是教育高质量发展的前提和保障。因此,追踪初任教师的自我认同的发展变化规律,识别其认同危机的特征,可以有效预防职后教师的认同危机。研究发现,小学初任教师职业自... 详细信息

初任教师职业自我认同影响教师个体的专业发展,事关教师队伍的稳定性,是教育高质量发展的前提和保障。因此,追踪初任教师的自我认同的发展变化规律,识别其认同危机的特征,可以有效预防职后教师的认同危机。研究发现,小学初任教师职业自我认同先下降后回升,变化丰富,初始水平显著反向影响自我认同的变化速度,群体分化明显。小学初任教师面临的职业自我认同危机有以下几个显著特征:第一学期认同危机高发;职业自我情感和行为倾向波动较大;职业自我认同的初始水平能够预测职业自我认同的后期变化,出现聚集性马太效应。为了提升初任教师的职业自我认同水平,有必要建立预防—辅导—淘汰三级教师职业认同管理机制:追踪职前教师的职业自我认同的变化,从源头阻断低职业自我认同的准教师进入教师行业;营造支持性的学校组织氛围,帮助初任教师顺利渡过危机高发期;打破“入职定终身”的教师聘用制度,建立完善的准入和退出机制,以提升教师队伍的整体质量。

关键词：初任教师职业自我认同追踪研究

昼夜节律下限时进食与2型糖尿病相关性的研究进展

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中国糖尿病杂志 2024年第8期32卷 634-637页

作者：丁蕊赵小艳李欣岳仁宋成都中医药大学附属医院内分泌科 610072

工作时间、进食时间、社会时差和睡眠不足等昼夜节律紊乱可提高T2DM发病风险。食物信号是引起外周生物钟振荡、调节昼夜节律的影响因素,对人体组织代谢有重要作用。限时进食(TRE)是一项新兴的饮食干预策略,通过控制每日进食时间、驱动... 详细信息

工作时间、进食时间、社会时差和睡眠不足等昼夜节律紊乱可提高T2DM发病风险。食物信号是引起外周生物钟振荡、调节昼夜节律的影响因素,对人体组织代谢有重要作用。限时进食(TRE)是一项新兴的饮食干预策略,通过控制每日进食时间、驱动生物钟基因和机体能量代谢的节律振荡,从而干预糖代谢。本文综述昼夜节律下TRE与T2DM相关性的研究进展。

关键词：限时进食糖尿病,2型昼夜节律生物钟

基于轨迹聚类的GNSS-IR多系统组合土壤湿度估计方法

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武汉大学学报（信息科学版） 2024年第1期49卷 37-46页

作者：郑南山何佳星丁锐章恒一中国矿业大学环境与测绘学院江苏徐州221116 自然资源部国土环境与灾害监测重点实验室江苏徐州221116

全球导航卫星系统干涉反射测量(global navigation satellite system-interferometric reflectometry,GNSS-IR)技术能探测浅层地表的土壤湿度。针对多系统组合的土壤湿度反演问题,基于轨迹聚类方法,从全球定位系统(global positioning system,GPS)、北斗卫星导航系统(BeiDou satellite navigation system,BDS)、格洛纳斯(GLONASS)、伽利略(Galileo)导航系统的信噪比观测数据中提取多径干涉相位,利用经验模型求解轨迹聚类后的土壤湿度估计值,以加权平均方式得到系统组合后的估计结果。结果表明,BDS、Galileo反演精度相当且优于GPS、GLONASS,基于轨迹聚类的多系统组合土壤湿度估计方法的均方根误差为0.0414 cm3/cm3,相比于单系统的综合反演精度提升约16.3%,相比于单系统的最佳频段反演精度提升约5.2%,所提方法能有效监测土壤湿度的变化。

关键词：土壤湿度 GNSS-IR 信噪比多系统组合轨迹聚类