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Researches on the Structure and Properties of Mullite Solid Solution Made from Industrial Waste

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Chinese Journal of Structural Chemistry 2006年第8期25卷 965-970页

作者： ruan yu-zhong yu yan wu ren-ping College of Materials Science and Engineering Fuzhou University Fuzhou 350002 China

The waste slag from aluminum profile factory and silicon fine powder from ferroalloy factory were utilized as the main raw materials to synthesize mullite solid solution Al4＋2xSi2-xO10-x/2, whose defect formation mechanism, crystalline phase composition, crystal cell parameters, microstructures and morphologies were characterized in detail by XRD and SEM. The results show that because of the ultrafine particle size of the materials, the content of mullite solid solution synthesized by this method is higher than that by regular method. Keywords： waste slag from aluminum factory, silicon fine powder, mullite, solid solution

关键词： waste slag from aluminum factory silicon fine powder mullite solid solution

Influence of Impurity Na_2O on Crystalline Structure of Cordierite Synthesized from Aluminum Sludge

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Chinese Journal of Structural Chemistry 2005年第1期24卷 29-34页

作者：于岩阮玉忠杜育红吴任平 College of Materials Science and Engineering Fuzhou University Fuzhou 350002 China

By adding small amount of TiO2, aluminum slag could be used to synthesize cor- dierite. α-Al2O3, TiO2 and dehydrated talc could generate solid solution to accelerate the solid-state reaction to form cordierite. The experimental results show that the content of cordierite increases with the increase of TiO2 added. 3.0% of TiO2 is determined to be the best amount, because all crystalline substances are converted into cordierite at this content. Philips X’pert plus software analysis shows that when the content of TiO2 is from 0 to 1.0%, cordierite has the same hexagonal structure as the single crystal and the lattice parameters change slightly; when the content of TiO2 is from 1.0 to 2.0%, the cordierite still keeps hexagonal structure but the lattice parameters change greatly; when the content of TiO2 is from 2.0 to 3.5%, the cordierite is converted from hexagonal into rhombic and the lattice parameters change accordingly.

关键词： aluminum slag TiO2 mineralizer cordierite crystalline structure

Multiple temporal scale relationships of bankfull discharge with streamflow and sediment transport in the Yellow River in China

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International Journal of Sediment Research 2013年第4期28卷 496-510页

作者： yan-yan ZHANG De-yu zhong Bao-sheng wu State Key Laboratory of Hydroscience and Engineering Tsinghua University Pearl River Hydraulic Research Institute Pearl River Water Resources Commission

This paper presents a study on the characteristics of multiple time scales of bankfull discharge and its delayed response to changes of tlow conditions using continuous wavelet analysis for data from selected hydrologieal stations in the Yellow River *** showed that bankfull discharge series had one or two dominant lime *** example,the Huayuankou station in the lower reach of the Yellow River had two dominant time scales of 19 20 years and 5 6 *** dominant time seales of the bankfull discharge series were generally consistent with the dominant time scales of water discharge and sediment concentration series,indicating thai the channel morphology inherits the characteristics of the hydrologieal system in terms of multiple time *** addition,the wavelet coefficients of the bankfull discharge series had a phase difference in relation to those of the sediment concentration series,with a delay time that varied from 3 to 16 years at different *** delay time or relaxation lime is a result of the delayed response of bankfull discharge to How conditions,which was significant for channel adjustments in response lo changes of tlow *** findings of the multiple lime scales and the delayed response are of importance for further study of channel morphology of fluvial systems.

关键词： Multiple time scales wavelet analysis bankfull discharge river morphology fluvial processes Yellow River

The control and optimization of macro/micro-structure of ion conductive membranes for energy conversion and storage

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Chinese Journal of Chemical Engineering 2016年第5期24卷 558-571页

作者： Xiaoming yan Wenji Zheng Xuehua ruan yu Pan Xuemei wu Gaohong He State Key Laboratory of Fine Chemicals School of Petroleum and Chemical EngineeringDalian University of Technology Research and Development Center of Membrane Science and Technology School of Chemical EngineeringDalian University of Technology

Ion conductive membranes(ICMs)are frequently used as separators for energy conversion and storage technologies of fuel cells,flow battery,and hydrogen pump,because of their good ion-selective conduction and low electronic ***,this feature article reviews the recent studies on the development of new nonfluorinated ICMs with low cost and their macro/micro-structure *** general,these new nonfluorinated ICMs have lower conductivity than commercial perfluorinated ones,due to their poor ion transport *** ion exchange capacity(IEC)would create more continuous hydrophilic channels,thus enhancing the ***,high IEC also expands the overall hydrophilic domains,weakens the interaction between polymer chains,enhances the mobility of polymer chains,and eventually induces larger *** micro-scale expansion and macro-scale swelling of the ICMs with high IEC could be controlled by limiting the mobility of polymer *** on this strategy,some ef ficient techniques have been developed,including covalent crosslinking,semi-interpenatrating polymer network,and ***,this review introduces the optimization of macro/microstructure of both perfluorinated and nonfluorinated ICMs to improve the ***-scale multilayer composite is an ef ficient way to enhance the mechanical strength and the dimensional stability of the ICMs,and could also decrease the content of per fluorosulfonic acid resin in the membrane,thereby reducing the cost of the perfluorinated *** side chain,multiple functionalization,small molecule inducing micro-phase separation,electrospun nano fiber,and organic–inorganic hybrid could construct more ef ficient ion transport channels,improving the ion conductivity of ICMs.

关键词： Ion conductive membranes Macrostructure Microstructure Optimization

Controlled synthesis and closed-loop chemical recycling of biodegradable copolymers with composition-dependent properties

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Science China Chemistry 2022年第5期65卷 943-953页

作者： Yi-Teng yan Gang wu Si-Chong Chen yu-zhong Wang The Collaborative Innovation Center for Eco-Friendly and Fire-Safety Polymeric Materials(MoE) National Engineering Laboratory ofEco-Friendly Polymeric Materials(Sichuan)State Key Laboratory of Polymer Materials EngineeringCollege of ChemistrySichuan UniversityChengdu 610064China

The closed-loop recycling concept of the polymer wastes into building-block chemicals is attractive,but the closed-loop recycling of copolymers enabled by energy-efficient chemical recycling and cost-effective separations is still facing great ***,for the first time,a one-pot sequential copolymerization of γ-butyrolactone(γ-BL) and p-dioxanone(PDO)using an economical ureas/alkoxides catalytic system is conducted to synthesize biodegradable and chemically recyclable poly-(γ-butyrolactone)-block-poly(p-dioxanone)(PγBL-b-PPDO) diblock copolymers with well-defined and controlled *** composition-dependent properties of PγBL-b-PPDO copolymers,including thermal properties and crystallization behavior,are *** results show that the thermal stability and crystalline ability of PγBL are enhanced observably by introducing the PPDO ***,the PγBL-b-PPDO copolymers can be depolymerized efficiently into the corresponding co-monomers with a yield of over 95% by simply low-temperature pyrolysis under ***,γ-BL and PDO monomers are selectively separated with an isolated purity of about 99% based on the difference in their physicochemical ***,their repolymerization is realized to obtain the copolymers with nearly identical structures and thermostability,demonstrating the closed-loop recycling of copolymers,i.e.,*** research provides important guidance for the design of novel sustainable polymers towards more efficient chemical recycling,separation and regeneration.

关键词： biodegradable copolyester poly(p-dioxanone) tunable properties closed-loop chemical recycling

Subsolidus binary phase diagram of the bilayer compounds [n-C_nH_(2n+1)N(CH_3)_3]_2ZnCl_4(n = 16, 18)

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Science China Chemistry 2014年第12期57卷 1703-1707页

作者： ruan Bei wu Ke zhong CHEN Jing XIONG yuan yuan ren Bi yan Department of Chemistry and Material Science Hebei Normal University

The bilayer compounds[n-CnH2n+1N(CH3)3]2Zn Cl4(n=16,18)experience solid-solid phase transition within the temperature range of 310 to 340 *** low-temperature crystal structures of the pure compounds are characteristic of the piling effect in which a 2D macro-anion Zn Cl42- is sandwiched between two alkylammonium *** layers become conformationally disordered in the high-temperature *** structures can alternatively be viewed as a double layer of alkylammonium ions between Zn Cl42- sheets and can be considered as crystalline models of lipid *** experimental subsolidus binary phase diagram of[n-C16H33N(CH3)3]2Zn Cl4-[n-C18H37N(CH3)3]2Zn Cl4 has also been established over the whole composition range by differential scanning calorimetry(DSC)and X-ray *** the phase diagram,one intermediate compound[n-C16H33N(CH3)3][n-C18H37N(CH3)3]Zn Cl4 at WC16C3Zn%47.50 and two eutectoid invariants points at WC16C3Zn%35.10 and75.70 were observed;the respective temperatures of the two eutectoids are 320±1 and 315±1 *** addition,there are three noticeable solid solution ranges in the phase diagram:α-phase at the left,β-phase at the right,andγ-phase in the middle.

关键词： lipid bilayers n-hexadecyltrimethylammonium tetrachlorozincate n-trimethylstearylammonium tetrachlorozincate phase transitions phase diagram

基于云-模糊模型的堆石坝施工质量评估（英文）

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2018年第4期19卷 289-303页

作者： Fei WANG Deng-hua zhong yu-ling yan Bing-yu ren Bin-ping wu State Key Laboratory of Hydraulic Engineering Simulation and Safety Tianjin University

目的:施工质量对于大坝建设期及运行期的安全至关重要。由于施工过程中的信息不完备及碾压质量与影响因素之间的关系并不是完全确定等原因,传统的评估方法很少考虑不确定性对施工质量的影响。本文旨在探讨考虑不确定性影响的碾压质量评... 详细信息

目的:施工质量对于大坝建设期及运行期的安全至关重要。由于施工过程中的信息不完备及碾压质量与影响因素之间的关系并不是完全确定等原因,传统的评估方法很少考虑不确定性对施工质量的影响。本文旨在探讨考虑不确定性影响的碾压质量评估方法,改善施工质量评估的可信性。创新点:1.通过研究模糊神经网络与径向基神经网络,结合云模型建立云-模糊模型;2.建立施工质量三指标体系评价方法。方法:1.通过碾压质量实时监控系统和现场试坑试验获取参数数据;2.通过云分析,建立云-模糊模型;3.对比不同的模型,验证云-模糊模型的可行性;4.利用验证的云-模糊模型对大坝施工仓面进行压实干密度预测;5.计算评价体系的三指标,对施工质量进行评估。结论:1.云-模糊模型不但能在精度上满足预测要求,而且能够综合考虑施工质量与影响因素之间的不确定性关系;2.云-模糊评价方法弥补了传统评价方法仅追求精度的单一性,使得施工质量评价更符合客观规律;3.提出的施工质量三指标评价体系充实了传统的评价方法,能够更客观地指导实际工程建设。

关键词：堆石坝云模型不确定性施工质量评价

Heat Treat ment of Die and Mould Oriented Concurrent Design

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Journal of Iron and Steel Research International 2006年第1期13卷 40-43,74页

作者： LI Xiong ZHANG Hong bing ruan Xue-yu LUO zhong-hua ZHANG yan Department of Plasticity Forming Engineering Shanghai Jiaotong University Shanghai 200030 China Department of Materials Engineering Shanghai Institute of Technology Shanghai 200235 China State Key Laboratory for Advanced Metals and Materials University of Science and Technology Beiiing Beijing 100083 China

Many disadvantages exist in the traditional die design method which belongs to serial pattern. It is well known that heat treatment is highly important to the dies. A new idea of concurrent design for heat treatment process of die and mould was developed in order to overcome the existent shortcomings of heat treatment process. Heat treatment CAD/CAE was integrated with concurrent circumstance and the relevant model was built. These investigations can remarkably improve efficiency, reduce cost and ensure quality of R and D for products.

关键词： die design heat treatment mould

Seeking magneto-structural correlations in easily tailored pentagonal bipyramid Dy (Ⅲ) single-ion magnets

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Science China Chemistry 2020年第8期63卷 1066-1074页

作者： Guo-Zhang Huang Ze-yu ruan Jie-yu Zheng yan-Cong Chen Si-Guo wu Jun-Liang Liu Ming-Liang Tong Key Laboratory of Bioinorganic and Synthetic Chemistry of Ministry of Education School of ChemistrySun Yat-Sen UniversityGuangzhou 510275China

Controlling molecular magnetic anisotropy via structural engineering is delicate and fascinating,especially for single-molecule magnets(SMMs).Herein a family of dysprosium single-ion magnets(SIMs)sitting in pentagonal bipyramid geometry have been synthesized with the variable-size terminal ligands and counter anions,through which the subtle coordination geometry of Dy(Ⅲ)can be finely tuned based on the size *** effective energy barrier(Ueff)successfully increases from 439 to 632 K and the magnetic hysteresis temperature(under a 200 Oe/s sweep rate)raises from 11 to 24 *** on the crystal-field theory,a semi-quantitative magneto-structural correlation deduced experimentally for the first time is revealed that the Ueff is linearly proportional to the structural-related value S20 corresponding to the axial coordination bond lengths and the bond *** the evaluation of the remanent magnetization from hysteresis,quantum tunneling of magnetization(QTM)is found to exhibit negative correlation with the structural-related value Stun corresponding to the axial coordination bond angles.

关键词： single-molecule magnets magnetic anisotropy crystal field magneto-structural correlation