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Mechanism of K/Ni Etching for Biochar-H_(2)O Gasification

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Journal of Harbin Institute of Technology(New Series) 2024年第3期31卷 1-18页

作者： Zhenyu Cheng Dongdong Feng Qi Shang Yijun Zhao wenda zhang Shaozeng Sun School of Energy Science and Engineering Harbin Institute of TechnologyHarbin 150001China

Biomass-H_(2)O gasification is a complex thermochemical reaction,including three processes of volatile removal:homogeneous/heterogeneous reforming,biochar gasification and *** rate-determining step is biochar-H_(2)O gasification and etching so the DFT is carried out to see the catalytic role of different metal elements(K/Ni)in the zigzag biochar *** calculation results show that the gasification of biochar-H_(2)O needs to go through four processes:dissociative adsorption of water,hydrogen transfer(hydrogen desorption,hydrogen atom transfer),carbon dissolution and CO *** energy barrier indicated that the most significant step in reducing the activation energy of K is reflected in the hydrogen transfer step,which is reduced from 374.14 kJ/mol to 152.41 kJ/mol;the catalytic effect of Ni is mainly reflected in the carbon dissolution step,which is reduced from 122.34 kJ/mol to 84.8 kJ/*** existence of K causes the edge to have a stronger attraction to H and does not destroy theπbonds of biochar *** destruction ofπbonds is mainly due to the role of H free radicals,while the destruction ofπbonds will lead to easier C-C bond *** shows a strong attraction to O in OH,which forms strong Ni-O chemical *** can also destroy the aromatic structure directly,making the gasification easier to *** study explored the catalytic mechanism of K/Ni on the biochar-H_(2)O gasification at the molecular level and looked forward to the potential synergy of K/Ni,laying a foundation for experimental research and catalyst design.

关键词： Biochar Potassium-nickel catalysis H_(2)O gasification etching Quantum chemistry Transition state theory

Revealing structure correlation between ionic liquid and metal-organic framework matrix

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Magnetic Resonance Letters 2024年第2期4卷 65-72页

作者： Ligang Xu wenda zhang Chenjie Lou Chenxu Geng Yuxiu Sun Jie Liu Yongchao Shi Huajie Luo Jipeng Fu Haiyan Zheng Mingxue Tang Center for High Pressure Science and Technology Advanced Research Beijing100193China College of Materials Science and Engineering Guilin University of TechnologyGuilin541004China State Key Laboratory of Separation Membranes and Membrane Processes School of Material Science and EngineeringTiangong UniversityTianjin300387China University of Science and Technology Beijing Beijing100083China Key Laboratory of Rare Earth Optoelectronic Materials and Devices of Zhejiang Province Institute of Optoelectronic Materials and DevicesChina Jiliang UniversityHangzhou310018China

Solid-state batteries are rising rapidly in response to the fast-increasing energy ***-organic framework(MOF) loaded with ionic liquids has brought new opportunities for solid-state batteries owing to its good interfacial compatibility and high ionic conductivity. MOF-808 is selected to be filled with Li-contained ionic liquid for structure and ion dynamics investigation using nuclear magnetic resonance(NMR) and X-ray *** study finds that the introduced ionic liquid would partially soften the matrix of MOF-808 and thus yield amorphous phase. By selective isotope replacement under cycling symmetric ^(6)Li metal cell, Li^(+)ion is observed to mainly go cross ionic liquid in the open channel of matrix under potential polarization.

关键词： Nuclear magnetic resonance Solid-state batteries MOF-808 Ionic liquid Local structure

Low Temperature Tetragonal Tungsten Bronze Oxides for Li-ion Storage

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CHEMICAL RESEARCH IN CHINESE UNIVERSITIES 2024年第5期40卷 922-926页

作者： Xu, Chengxin zhang, wenda Lou, Chenjie Li, Chengyu Xu, Ligang Shi, Yongchao Liu, Jie Luo, Huajie Fu, Jipeng Kuang, Xiaojun Tang, Mingxue Guilin Univ Technol Coll Chem & Bioengn Guangxi Key Lab Electrochem & Magnetochem Funct Ma Guilin 541006 Peoples R China Ctr High Pressure Sci & Technol Adv Res Beijing 100193 Peoples R China Guilin Univ Technol Key Lab New Proc Technol Nonferrous Met & Mat Guangxi Key Lab Opt & Elect Mat & Devices Coll Mat Sci & EngnMinist Educ Guilin 541004 Peoples R China Univ Sci & Technol Beijing Sch Mat Sci & Engn Minist Educ Beijing 100083 Peoples R China Univ Sci & Technol Beijing Key Lab Adv Mat & Devices Postmoore Chips Minist Educ Beijing 100083 Peoples R China China Jiliang Univ Inst Optoelect Mat & Devices Key Lab Rare Earth Optoelect Mat & Devices Zhejian Hangzhou 310018 Peoples R China

Nb-based tungsten bronze oxides have emerged as attractive materials in various fields, owing to the structural openings and simple synthesis method. In this work, the tetragonal tungsten bronze (TTB) NaWNbO6 was prepared by solid state reaction at a relatively low temperature of 775 degrees C. The local structure was systematically studied by solid state nuclear magnetic resonance (SSNMR) with the aid of transition electronic microscopy (TEM). The analysis indicates that NaWNbO6 has pentagonal, square, and triangular tunnels. Notably, square tunnels were partly occupied (50%) by Na, which creates the ability for the Li-ion storage with a volumetric capacity of 210 AhL-1 at 0.2 C. The 2D Na-23-Na-23 EXSY results further suggest the ability of ions to fast exchange between the tetragonal and pentagonal tunnels, resulting in a high-rate performance 20 C.

关键词： Tetragonal tungsten bronze Solid-state Na-23 NMR Nb-93 NMR spectrum Fast ion exchange

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天然气调质煤粉再燃中关键参数的实验研究

煤炭学报 2024年第7期49卷 3245-3252页

作者：李玉凯孙绍增赵义军张文达冯冬冬哈尔滨工业大学能源科学与工程学院黑龙江哈尔滨150001

针对煤粉再燃技术,提出了一种结合再循环烟气输送煤粉和天然气调质的方案。其目的在于提高再燃煤粉的还原能力,从而降低燃煤锅炉产生的氮氧化物排放。为了探索如何利用天然气中高活性成分,创造一个更有利于煤粉还原NO_(x)的环境,利用模... 详细信息

针对煤粉再燃技术,提出了一种结合再循环烟气输送煤粉和天然气调质的方案。其目的在于提高再燃煤粉的还原能力,从而降低燃煤锅炉产生的氮氧化物排放。为了探索如何利用天然气中高活性成分,创造一个更有利于煤粉还原NO_(x)的环境,利用模拟实际燃煤锅炉条件下的多反应控制段携带流反应器实验系统,研究了天然气调质的整个过程。结果表明,天然气调质产生的大量还原性物质,如CO*、OH*、H和CHi等优化了煤焦的物理化学结构,增强了煤焦还原氮氧化物的能力。与传统的再循环烟气输送煤粉相比,添加天然气调质后,NO_(x)的还原效率提高了约12.23%。通过实验和数据分析,解析了天然气调质技术对于煤粉再燃的显著影响,并提出了在工程应用中的具体参数要求。从工程应用角度来看,为了实现高效率的氮氧化物还原,并兼顾煤粉的燃烬和经济性,需要对再燃区的过量空气系数、停留时间和燃料比进行精确控制,分别为0.8、0.6 s和20%。总的来说,采用天然气调质技术可在保证氮氧化物超低排放的同时,尽量减少活性气体的使用,从而提高系统运行的经济性。该灵活的天然气使用技术不仅在实验室条件下取得了良好的效果,也为工程实践提供了可行的方案,保证系统运行的经济性。

关键词：天然气调质再燃 NOx 燃烧参数

SUP-ADDITIVE METRIC PRESSURE OF DIFFEOMORPHISMS

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Acta Mathematica Scientia 2022年第2期42卷 575-587页

作者： wenda zhang Zhiqiang LI College of Mathematics and Statistics Chongqing Jiaotong UniversityChongqing 400074China College of Mathematics and Statistics Chongqing UniversityChongqing 401331China

In this paper,we study the pressure of C^(1)-smooth partially hyperbolic diffeomorphisms with sup-additive *** give several definitions of the so called unstable(measure theoretic)pressure in terms of Bowen’s picture and the capacity *** show that all such unstable metric pressures of a given ergodic measure equals the corresponding unstable measure theoretic entropy plus the Lyapunov exponent of the potentials with respect to the ergodic measure.

关键词： Partially hyperbolic systems unstable measure theoretic pressure sup-additive potentials

Mechanism of K ／ Ni Etching for Biochar.H2O Gasification

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Influence of Rare Earth Modification and Homogenization on the Microstructure and Mechanical Properties of Recycled Can 3004 Aluminum

哈尔滨工业大学学报（英文版） 2024年第3期 1页

作者： Zhenyu Cheng Dongdong Feng Qi Shang Yijun Zhao wenda zhang Shaozeng Sun

来源：博看期刊评论

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Journal of Wuhan University of Technology(Materials Science) 2014年第2期29卷 264-268页

作者：段瑞斌白培康 YANG Jing zhang wenda DING Hao School of Materials Science and Engineering North University of China

The microscopic structure of waste can aluminum material was researched by adding A15TiB refining agent, La-Ce rare earth and mixed rare earth modifiers, and the microstructure and mechanical performance of the modified aluminum material were studied. The experimental results show that the optimal refiner addition amount is 1.1wt%; the material performance can be significantly improved when the content of La-Ce rare earth ranges to a certain degree, but the mixed rare earth barely affects the refinement effect of the aluminum. When being homogenized, the mixed rare earth plays more obvious role in refining the aluminum material than La-Ce rare earth. The optimal plan is modifying the aluminum material with 3wt% mixed rare earth and homogenizing with annealing temperature of 580℃, annealing time of 12 hours and heating rate of 5℃/min while refining the material with 1.1wt% A1-5Ti-IB.

关键词： modification homogenization microstructure mechanical performance recycled can aluminum

The Role of Ti in the Preparation of SiC/7075 Aluminum Matrix Composite

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Journal of Wuhan University of Technology(Materials Science) 2020年第2期35卷 293-298页

作者： zhang wenda CHEN Chengcheng XU Hong CHE Luchang GUO Cuiping DU Zhenmin Department of Materials Science and Engineering University of Science and Technology BeijingBeijing 100083China School of Materials Science and Engineering North University of ChinaTaiyuan 030051China Southwest Technique and Engineering Institute Chongqing 400039China

SiC/7075 aluminum matrix composites were prepared by a liquid stirring *** role of Ti facilitating the preparation of SiC/7075 aluminum matrix were studied by means of direct-reading spectrometer,scanning electron microscope,energy dispersive spectrometer,X-ray diffraction and the sessile drop *** results show that the SiC content in the SiC/7075 composite increases with an increase of Ti *** addition of Ti can significantly improve the wettability of SiC/Al system,there is a critical value of above 0.5%of Ti content in improving the wettability of the Al/SiC system at *** temperature of the"non wetting-wetting"transition for the(Al-2Ti)/SiC system is about 1123K,the contact angle decreases to 88°at 200 seconds and reaches a stable contact angle of 28°at 2100 seconds.

关键词： aluminum matrix composites Al3Ti particles SiC particles wettability

气-粉复合精炼方式对ZL205A净化效果的影响

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特种铸造及有色合金 2024年第3期44卷 354-358页

作者：张钰鑫张文达王宇宋和谦毛红奎朱嘉伟徐宏中北大学材料科学与工程学院太原030051

对ZL205A合金进行了不同顺序的熔剂(粉)和旋转喷吹(氩气)以及旋转喷吹内喷粉复合精炼,利用测氢仪、金相显微镜、拉伸试验机、扫描电镜分析了不同气-粉复合方式的净化效果。结果表明,熔剂能增大夹杂与熔体界面活性,降低铝液黏度,其与旋... 详细信息

对ZL205A合金进行了不同顺序的熔剂(粉)和旋转喷吹(氩气)以及旋转喷吹内喷粉复合精炼,利用测氢仪、金相显微镜、拉伸试验机、扫描电镜分析了不同气-粉复合方式的净化效果。结果表明,熔剂能增大夹杂与熔体界面活性,降低铝液黏度,其与旋转喷吹氩气复合方式对ZL205A合金熔体除气除杂效果有较大影响;旋转喷吹内喷粉工艺取得了最佳净化效果,熔体氢含量从0.176 mL/(100 g)Al降到了0.087 mL/(100 g)Al,材料的屈服强度、抗拉强度和伸长率较未精炼合金分别提高了19.2%、18.3%和100%。

关键词： ZL205A 旋转喷吹复合精炼氢含量力学性能