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基于XRD及FTIR的固废型纳米高硫水泥的微观特性

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光谱学与光谱分析 2023年第6期43卷 1974-1980页

作者：宗志芳龙红明 Yilin Gui 张浩董伟周晓慧季益龙冶金工程与资源综合利用安徽省重点实验室(安徽工业大学) 安徽马鞍山243002 安徽工业大学建筑工程学院安徽马鞍山243032 School of Civil and environmental Engineering Queensland University of TechnologyBrisbaneQLD 4000Australia

水泥中的硫酸盐含量过高会带来后期体积膨胀的风险。采用纳米TiO_(2)和纳米SiO_(2)对含有CaSO_(3)·0.5H_(2)O的半干法烧结烟气脱硫灰改性,以纳米改性半干法烧结烟气脱硫灰为混合材制备固废型纳米高硫水泥,解决混合材中CaSO_(3)·0.5H_(... 详细信息

水泥中的硫酸盐含量过高会带来后期体积膨胀的风险。采用纳米TiO_(2)和纳米SiO_(2)对含有CaSO_(3)·0.5H_(2)O的半干法烧结烟气脱硫灰改性,以纳米改性半干法烧结烟气脱硫灰为混合材制备固废型纳米高硫水泥,解决混合材中CaSO_(3)·0.5H_(2)O含量高带来的耐久性不良问题。根据固废型纳米高硫水泥的安定性、标准稠度用水量,凝结时间以及抗压强度等性能的发展变化规律,确定了各组分的掺量配比和制备参数。采用LPSA分析了原材料的粒径分布区间,采用接触角测量仪分析了硬化浆体的浸润性能,采用XRD分析了原料及硬化浆体的矿物成分,采用FTIR分析了原料及硬化浆体的组织结构的变化规律,采用SEM分析了原料及硬化浆体的微观形貌。结果表明,半干法烧结烟气脱硫灰的粒径分布区间为0.31~127.38μm比水泥颗粒粒径分布区间更宽、粒度更细,能够优化水泥的级配范围。半干法烧结烟气脱硫灰的加入对水泥水化起到一定的缓凝作用,延长了凝结时间,掺量较大会带来同龄期硬化浆体抗压强度的降低。纳米SiO_(2)与纳米TiO_(2)的加入能够降低高硫水泥体系的标准稠度用水量,提高其抗压强度。3 Wt%的纳米TiO_(2)与2 Wt%的纳米SiO_(2)协同改性能够有效稳定半干法烧结烟气脱硫灰中的CaSO_(3)·0.5H_(2)O,进一步激发半干法烧结烟气脱硫灰的潜在活性,提高水泥硬化浆体的力学性能。改性后固废型纳米高硫水泥28 d的抗压强度为64.72 MPa比未改性的高硫水泥提高了83%,比纯水泥提高了16%。纳米改性后,润湿边角增大向疏水转变,有利于耐久性的提高;XRD分析结果显示水化产物中类AFm’含量很低,降低了膨胀的风险;FTIR分析结果显示水化产物中Ca(OH)_(2)中含有的—OH的伸缩振动峰增强,进一步提高了硬化浆体的抗化学侵蚀能力;SEM分析结果显示水化产物质地均匀,组织缺陷少。纳米TiO_(2)与纳米SiO_(2)协同改性半干法烧结烟气脱硫灰可以稳定其中含有余有的硫酸盐、亚硫酸盐,制备出高性能固废型纳米高硫水泥,有利于降碳减碳,节能环保。

关键词：半干法脱硫灰胶凝材料纳米改性亚硫酸盐微观结构

Synthesis of 4-Methyl-2-Isopropyl-1,3-Dioxolane by TiSiW_(12)O_(40)/TiO_2 as Catalyst

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合成化学 2004年第Z1期12卷 66-66页

作者： YANG Shui-jin YU Xie-qing Department of Chemistry and environmental Engineering Hubei Normal University Huangshi 435002 China Department of Chemistry and Environmental Engineering Hubei Normal University Huangshi 435002 China

Acetals and ketals are a kind of the important compounds and used to protect carbonyl,middle material of the organic synthesis. What's more, they are a sort of the widely use flavor substance. 4-Methyl-2-isopropyl-1,3-dioxolane has fresh fruit odor and apple note. It is used to producing many sorts of essence. And the conventional method to synthesize 4-methyl-2-isopropyl-1,3-dioxolane makes use of sulfuric acid as catalyst in factories. But it causes many problems, such as the erosion of production equipment, difficulty after-treatment, low quality of the products, etc. HPA and its salts shows excellent catalytic activity to the esterification and have recently attracted much attention as catalysts for various industrial processes, because their acidic and redox properties can be controlled at atomic/molecular levels. Misono, Pope [1], and Wang [2]have reviewed the homogeneous catalysis and fine organic synthesis catalyzed by heteropoly compounds. However, there is no report on the synthesis of 4-methyl-2-isopropyl-1,3-dioxolane catalyzed by TiSiW12O40/TiO2. TiSiW12O40/TiO2 was prepared according to reference [3] and identified by means of IR and XRD. The reaction was carried out in a three-neck flask equipped with a stirrer, a reflux condenser, and a thermometer. A certain amounts of isobutyraldehyde,1,2-propanediol and the catalyst was heated to boiling and refluxed until no water flowed off. The purified product was analyzed by IR spectra and *** this paper, we report 4-methyl-2-isopropyl-1,3-dioxolane was synthesized from isobutyraldehyde and 1,2-propanediol in the presence of TiSiW12O40/TiO2. The factors influencing the yield of product and the optimum reaction conditions were discussed. The optimum conditions are molar ratio of isobutyraldehyde to 1,2-propanediol was 1:1.5, the quantity of catalyst was equal to 0.5% feed stock, and the reaction time was 1.0 h. TiSiW12O40/TiO2 was an excellent catalyst to synthesize 4-methyl-2-isopropyl-1,3-dioxolane and

关键词： 4-Methyl-2-isopropyl-1,3-dioxolane, TiSiW12O40/TiO2, catalysis, acetalation.

On the wave catching-up phenomenon in a two-layer nonlinearly elastic composite bar

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On the wave catching-up phenomenon in a two-layer nonlinearl...

Low-temperature Synthesis of Belite Cement from Reactive Mixtures Based on Coal Fly Ash

23rd International Congress of Theoretical and Applied Mechanics

作者： Shoujun Huang Huihui Dai Zhen Chen Dexing Kong Department of Mathematics Anhui Normal University Department of Mathematics City University of Hong Kong Department of Civil and environmental Engineering University of MissouriColumbiaUSA Department of Engineering Mechanics Dalian University of Technology Department of Mathematics Zhejiang University

＜正＞Cracking induced by tensile wave at the free surface of an impacted target is an important issue in impact-resistant design. Here,we explore to use material nonlinearity to undermine the strength of the tensile ...

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Journal of Civil Engineering and Architecture 2012年第2期6卷 189-196页

作者： Nadezda Stevulova Ivana Filkova Kestutis Baltakys Institute of Building and environmental Engineering Civil Engineering Faculty Technical University of Kosice 042 O0 KosiceSlovak Republic Department of Silicate Technology Faculty of Chemical Technology Kaunas University of Technology Radvilenu st. 19 C-144 L T- 50254 Kaunas Lithuania

This paper summarizes the selected results of an extensive investigation of application of two methods （hydrothermal and mechanochemical） assisted by calcination for synthesizing belite cement from reactive mixtures （CaO/SiO2 molar ratio of 2） consisting of various waste kinds from fluidized brown coal combustion in Slovakian power plant and CaO addition. Based on XRD diffraction patterns and infrared spectra ofpre-treatment products, the formation of the new profiles corresponding to CSH phases with low degree of ordering as belite precursors after hydrothermal treatment as well as metastables calcium silicates and aluminosilicates in mechanosynthesized products was confirmed. Calcination of hydrothermally treated products led to transformation of CSH phases to wollastonite （CS）, belite and gehlenite phase, whereas creation oft^- and I^-C2S or wollastonite in milled reactive mixture took place. Differences in phase composition of products before and after calcination depend upon waste quality and precursor＇s synthesis conditions. Bottom ash isn＇t suitable as raw material for synthesizing belite phase because of high CaO content fixed in anhydrite form （44.1%）. Coal fly ash with low CaO content in anhydrite form （4.2%） and its mechanochemical or hydrothermal treatment in combination with subsequent heating offer opportunities for the utilization of coal fly ash as raw material for belite production.

关键词： Coal fly ash hydrothermal pre-treatment mechanosynthesis belite.

MnO2/porous graphene fiber electrode for supercapacitor

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MnO2/porous graphene fiber electrode for supercapacitor

An Educational GUI-Based Software for Dynamic Analysis of Framed Structural Models

中国化学会第九届全国无机化学学术会议

作者： Jinyang Zhang Xiaofan Yang Yonglong Bai Yibo He Liping Kang Hua Xu Feng Shi Zhibin Lei Zong-Huai Liu Key laboratory of Applied Surface and Colloid Chemistry （Shaanxi Normal University） Ministry of EducationSchool of Materials Science and Engineering Shaanxi Normal University

Fiber materials have been given wide attention because they play a critical role in our life, and they have been widely used as structure materials. Graphene possess extraordinary electrical conductivity, high surface area, chemical stability, and a distinct 2D nanostructure, it may be promising candidate for preparing carbon-based fiber material [1]. Although manganese oxides have received tremendous attention for electrochemical capacitors due to its low cost, abundance, high theoretical specific capacitance and good environmental compatibility, the disadvantages of the small specific surface area and low electrical conductivity limit their application as the electrode materials of electrochemical capacitors [2]. In the present work, Mn O2/porous graphene fiber electrode for supercapacitor has been prepared by three steps. At firstly, graphite oxide（GO） suspension（20 mg/m L） is injected into a mixed coagulating liquid of CH3 OH and Na OH, and the obtained sample is washed with methanol, dried at room temperature, GO fiber is obtained. Secondly, GO fiber is soaked in 0.5 M H3PO4 solution for 12 h, and then calcined at 650 °C for 2 h in N2, the hole graphite fiber（HRGO） was prepared. Third, the hole graphite fiber is soaked in 0.5 m M KMn O4 solution and stirred at 65 °C for 3 h, the Mn O2/porous graphene fiber electrode material is finally prepared. The prepared Mn O2/porous graphene fiber electrode materials have been characterized and their electrocapacitive properties are investigated by cyclic voltammetry and galvanostatic charge-discharge in a three electrode system in 6 M KOH. The research results indicate that Mn O2 are uniformly coated on the inside and outside surface of the hole graphene fibers, and the optimum Mn O2/porous graphene fiber electrode possesses a relatively high specific capacitance of 186 F g-1 at current density of 1 A g-1. The prepared fiber electrode will support a new process for improving the rate capability and capacitance of carbon-m

关键词： Porous graphene fiber Mn O2 Mn O2/porous graphene fiber capacitance

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Journal of Software Engineering and Applications 2023年第7期16卷 265-286页

作者： Claudio H. B. Resende Pedro C. Lopes Rafael L. Rangel Luis F. Paullo Muñoz Luiz F. Martha Department of Civil and environmental Engineering Pontifical Catholic University of Rio de Janeiro Rio de Janeiro Brazil Institute of Computing Fluminense Federal University Niter&#243i Brazil International Centre for Numerical Methods in Engineering (CIMNE) Universitat Politècnica de Catalunya Barcelona Spain

This paper introduces a new version of the open-source educational software, LESM (Linear Elements Structure Model), developed in MATLAB for structural analysis of one-dimensional models such as frames, trusses, and grillages. The updated program includes dynamic analysis, which incorporates inertial and damping effects, time-dependent load conditions, and a transient solver with multiple time integration schemes. The software assumes small displacements and linear-elastic material behavior. The paper briefly explains the theoretical basis for these developments and the reorganization of the source code using Object-Oriented Programming (OOP). The updated Graphical User Interface (GUI) allows interactive use of dynamic analysis features and displays new results such as animations, envelope diagrams of internal forces, phase portraits, and the response of degrees-of-freedom in time and frequency domain. The new version was used in a structural dynamics course, and new assignments were elaborated to improve students’ understanding of the subject.

关键词： Structural Analysis Structural Dynamics Educational Software MATLAB Graphical User Interface

Mechanical Study of the Utilization of Niger Coal Bottom Ash as an Additive in Cement Production

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材料科学与工程（中英文A版） 2015年第1期5卷 87-92页

作者： Nafissatou Savadogo Adamah Messan Francois Tsobnang Prince William Agbodjan International Institute for Water and environmental Engineering Laboratory of Eco-Materials for Construction Ouagadougou 01 BP 594 Burkina Faso Institut National des Sciences Appliquees Laboratoire Genie Civil et Genie Mecanique Rennes 35000 France

CBA (coal bottom ash) is an industrial waste generated by coal fired thermal power plant. In this work, we investigate the utilization as an additive material in composite cement of CBA resulting from the firing of the coal extracted in Tefereyre mine (TCBA) in a thermal power plant in Niger. Our investigations are carried out by using compressive mechanical tests on 40 × 40 × 160 mm3 mortar specimens. These mortar specimens are made with a partial substitution of the cement by TCBA at levels of 0%, 5%, 10%, 15%, 20% and 25% by mass. The tests were performed on the specimens at 7, 14, 28, 45 and 56 days of age. The results were used to evaluate the pozzolanic activity index as the ratio of the compressive strength of mortar containing 25% of coal bottom ash on that of the control mortar containing 100% of cement, according to ASTM C618. From these data, the maximum rate of TCBA addition in Portland cement was derived. It was found that TCBA has a pozzolanic activity index of about 71% at 28 days and displays a maximum substitution rate of 15% in Portland cement. These results strongly support the development of composite cement using TCBA.

关键词：燃煤火电厂水泥生产添加剂尼日尔底灰波特兰水泥砂浆试件机械

Uncertainty Optimization Design of Vehicle Body Structure Considering Random Deviations

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Uncertainty Optimization Design of Vehicle Body Structure Co...

Retraction Note:Tree species diversity predicts aboveground carbon storage through functional diversity and functional dominance in the dry evergreen Afromontane forest of Hararghe highland,Southeast Ethiopia

2018中国汽车工程学会年会

作者： ZHOU Jianhua LAN Fengchong CHEN Jiqing LAI Fanjie School of Mechanical & Automotive Engineering South China University of Technology South China University of Technology Guangdong Provincial Key Laboratory of Automotive Engineering

During the vehicle body manufacturing,because of the processing technology,the environmental and other uncertain factors,there has to be a little difference between theactual value and the design value of platethickness,the material characteristics,etc...Therefore,the performance of the vehicle body processedaccording to the *** fluctuations may make structural performance fail to meet the design ***,anoptimization design is executed with 6σ robustness criteria and MCS single-loop optimization strategy based on the radial basis function neural network approximate model,considering the deviationsin plates’ thickness,elastic modulus and welding spot’s diameter,so called the uncertainty optimization design *** example,taking the bending stiffness,torsion stiffnessand 1 st-order frequency as constraints,the method is applied in lightweight design of a car body structure,and the comparison between the reliability ofdeterministicoptimization design and uncertainty optimization design is *** shows that the uncertainty optimization design solution is effective and feasible,without lowering the static stiffness and modalperformance,while the weight is reduced.

关键词： body structure lightweight approximate models 6orobustness criteria MCS single-loop optimization strategy

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Ecological Processes 2023年第1期12卷 588-588页

作者： Mengistu Teshome Wondimu Zebene Asfaw Nigussie Muktar Mohammed Yusuf Wondo Genet College of Forestry and Natural Resources Hawassa UniversityHawassaEthiopia College of Natural Resources and environmental Science Oda Bultum UniversityChiroEthiopia

The Editor-in-Chief has retracted this article as it contains material that substantially overlaps with the following article(Mensah et al.2016).Mengistu Teshome Wondimu does not agree to this *** Asfaw Nigussie and M... 详细信息

关键词： forest evergreen aboveground