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Solvability and thermal response of cellulose with different crystal configurations
Qian CHEN, Kai ZHENG, Qingtao FAN, Kun WANG, Haiyan YANG, Jianxin JIANG, Shijie LIU
《工程管理前沿(英文)》 2019年 第6卷 第1期 页码 62-69 doi: 10.1007/s42524-019-0001-z
Cellulose is a biodegradable and renewable natural material that it is naturally resistant to breaking and modification. Moreover, the crystalline structure of cellulose is a major factor restricting its industrial utilization. In this study, cellulose polymorphs were prepared from natural cellulose, and their solvability and thermal response were investigated. Using liquid- and solid-state NMR signals, the distinct types and dissolving states of cellulose polymorphs were identified. The thermal behavior of the polymorphic forms of cellulose-d was also evaluated, and cellulose II exhibited the poorest thermal stability and a unique exothermic reaction.
关键词: cellulose crystal structure thermal response XRD CP/MAS 13C NMR
《环境科学与工程前沿(英文)》 2022年 第16卷 第10期 doi: 10.1007/s11783-022-1562-3
● 548 representative nor genes were collected to create complete phylogenetic trees.
关键词: N2O Greenhouse gas NO reductase NO dismutase Primer Crystal structure
Song ZHANG, Lelun WANG, Anze YI, Honggang GU, Xiuguo CHEN, Hao JIANG, Shiyuan LIU
《机械工程前沿(英文)》 2020年 第15卷 第2期 页码 256-264 doi: 10.1007/s11465-019-0573-7
关键词: ferroelectric liquid crystal polarization rotator (FLCPR) dual liquid crystal Mueller matrix polarizer design and optimization
Liu Jin-Xun,Wang Peng,Xu Wayne,Hensen Emiel J. M.
《工程(英文)》 2017年 第3卷 第4期 页码 467-476 doi: 10.1016/J.ENG.2017.04.012
费托合成(FTS)是近年来越发重要的能源转化途径,它可将一氧化碳和氢气的合成气转化为液态燃料和化学品,合成气的原料来自煤炭、天然气或生物质。在费托合成反应中,分散的过渡金属纳米粒子作为催化剂,用于催化以碳- 碳键生成为基础的反应。催化剂的催化活性和选择性与纳米粒子的电子结构和几何结构密切相关,具体取决于纳米粒子的尺寸、形态和晶相。在本文中,我们将回顾近期关于费托合成反应催化剂的体相和表面敏感性方面的工作。通过深入理解以上参数对不同催化剂行为的影响,有助于指导设计开发出更高活性、稳定性以及更优选择性的催化剂。
关键词: 费托合成 Fe、Co、Ru 碳化物 尺寸效应 晶相结构
Research progress on ultra-precision machining technologies for soft-brittle crystal materials
Hang GAO,Xu WANG,Dongming GUO,Yuchuan CHEN
《机械工程前沿(英文)》 2017年 第12卷 第1期 页码 77-88 doi: 10.1007/s11465-017-0411-8
Soft-brittle crystal materials are widely used in many fields, especially optics and microelectronics. However, these materials are difficult to machine through traditional machining methods because of their brittle, soft, and anisotropic nature. In this article, the characteristics and machining difficulties of soft-brittle and crystals are presented. Moreover, the latest research progress of novel machining technologies and their applications for soft-brittle crystals are introduced by using some representative materials (e.g., potassium dihydrogen phosphate (KDP), cadmium zinc telluride (CZT)) as examples. This article reviews the research progress of soft-brittle crystals processing.
关键词: brittle soft functional crystal ultra-precision machining
Yuexin Hou, Xiaoyun Li, Minghui Sun, Chaofan Li, Syed ul Hasnain Bakhtiar, Kunhao Lei, Shen Yu, Zhao Wang, Zhiyi Hu, Lihua Chen, Bao-Lian Su
《化学科学与工程前沿(英文)》 2021年 第15卷 第2期 页码 269-278 doi: 10.1007/s11705-020-1948-3
关键词: hierarchical zeolites single crystalline interconnected pores improved diffusion performance benzyl alcohol self-etherification reaction
Crystal modification of rifapentine using different solvents
Kun ZHOU, Jun LI, Jianhong LUO, Dongsheng ZHENG,
《化学科学与工程前沿(英文)》 2010年 第4卷 第1期 页码 65-69 doi: 10.1007/s11705-009-0302-6
关键词: identical scanning calorimetry different comparative dissolution structure modification
Qianqian Guo, Irmgard Kalf, Ulli Englert
《化学科学与工程前沿(英文)》 2018年 第12卷 第3期 页码 433-439 doi: 10.1007/s11705-018-1743-6
Diffusion reaction of the labile building block Mg(acacCN)2 (acacCN= 3-cyanoacetylacetonate) with silver salts leads to a series of solvated Mg/Ag bimetallic coordination polymers with composition [Mg(acacCN)3Ag]·solvent. Despite their common stoichiometry, the topology of these polymers depends on the solvent of crystallization. The two-dimensional coordination compound [Mg(acacCN)3Ag]·4CHCl3 in space group P
关键词: ditopic ligand substituted acetylacetone desolvation diffraction
DyFe11Ti磁结构及其自旋重取向的中子衍射研究 Article
Olivier Isnard, Eder J. Kinast
《工程(英文)》 2020年 第6卷 第2期 页码 153-157 doi: 10.1016/j.eng.2019.11.009
本文报道了通过中子粉末衍射探测DyFe11Ti的磁结构及其热演化规律。使用了变温中子衍射技术来测量磁矩及其取向的温度依赖性。Dy和Fe磁矩以反向平行的方式形成亚铁磁性耦合,其2 K时的易磁化方向是基面(a, b)内的[110]轴。随着温度的升高,该磁结构先后经历了两次自旋重取向现象。低温下,Dy磁矩较大,达到9.7μB,而在200 K时磁矩迅速下降到7.5μB。在Fe 8i位置观察到了最大的Fe磁矩。尽管磁结构发生了很大的变化,但在研究的温度范围内ThMn12型晶体结构一直保持不变。在第一阶段的自旋重取向温度(TSR1)时,观察到了易磁化轴的急剧倾斜;易磁化轴与晶体c轴之间的夹角从2 K的90°减小到200 K时的约20°(其中c轴是200 K以上的易磁化轴);同时Dy和Fe磁矩保持反向平行耦合。
关键词: 中子衍射,磁相图,晶体结构
Microstructure and electrical properties of NaNbO
Shihui XIE, Kongjun ZHU, Jinhao QIU, Hua GUO
《机械工程前沿(英文)》 2009年 第4卷 第3期 页码 345-349 doi: 10.1007/s11465-009-0050-9
关键词: Lead-free piezoelectric ceramics NaNbO3-BaTiO3 piezoelectricity ceramics crystal structure microstructure
Shuman Xu, Xiaoxiao Zhang, Dangguo Cheng, Fengqiu Chen, Xiaohong Ren
《化学科学与工程前沿(英文)》 2018年 第12卷 第4期 页码 780-789 doi: 10.1007/s11705-018-1733-8
关键词: hierarchical ZSM-5 crystal size catalytic cracking Thiele modulus effectiveness factor
《化学科学与工程前沿(英文)》 2023年 第17卷 第10期 页码 1503-1515 doi: 10.1007/s11705-022-2294-4
关键词: insoluble drugs polymer inhibition crystallization crystal growth kinetics DFT calculations
Novel casting processes for single-crystal turbine blades of superalloys
Dexin MA
《机械工程前沿(英文)》 2018年 第13卷 第1期 页码 3-16 doi: 10.1007/s11465-018-0475-0
This paper presents a brief review of the current casting techniques for single-crystal (SC) blades, as well as an analysis of the solidification process in complex turbine blades. A series of novel casting methods based on the Bridgman process were presented to illustrate the development in the production of SC blades from superalloys. The grain continuator and the heat conductor techniques were developed to remove geometry-related grain defects. In these techniques, the heat barrier that hinders lateral SC growth from the blade airfoil into the extremities of the platform is minimized. The parallel heating and cooling system was developed to achieve symmetric thermal conditions for SC solidification in blade clusters, thus considerably decreasing the negative shadow effect and its related defects in the current Bridgman process. The dipping and heaving technique, in which thin-shell molds are utilized, was developed to enable the establishment of a high temperature gradient for SC growth and the freckle-free solidification of superalloy castings. Moreover, by applying the targeted cooling and heating technique, a novel concept for the three-dimensional and precise control of SC growth, a proper thermal arrangement may be dynamically established for the microscopic control of SC growth in the critical areas of large industrial gas turbine blades.
关键词: superalloy investment casting Bridgman process directional solidification single crystal turbine blade
Polymorphism and crystal transformation of penicillin sulfoxide
Dingding JING, Yongli WANG, Zhijian CHEN, Lina ZHOU, Jingkang WANG
《化学科学与工程前沿(英文)》 2011年 第5卷 第4期 页码 442-447 doi: 10.1007/s11705-011-1140-x
关键词: penicillin sulfoxide crystallization polymorphism crystal transformation Raman spectroscopy
Junbo Gong, Dejiang Zhang, Yuanyuan Ran, Keke Zhang, Shichao Du
《化学科学与工程前沿(英文)》 2017年 第11卷 第2期 页码 220-230 doi: 10.1007/s11705-017-1624-4
关键词: clindamycin phosphate solvate crystal structure thermal stability moisture stability
标题 作者 时间 类型 操作
Solvability and thermal response of cellulose with different crystal configurations
Qian CHEN, Kai ZHENG, Qingtao FAN, Kun WANG, Haiyan YANG, Jianxin JIANG, Shijie LIU
期刊论文
Phylogenetic diversity of NO reductases, new tools for monitoring, and insights into NO production in natural and engineered environments
期刊论文
Dynamic modulation performance of ferroelectric liquid crystal polarization rotators and Mueller matrix
Song ZHANG, Lelun WANG, Anze YI, Honggang GU, Xiuguo CHEN, Hao JIANG, Shiyuan LIU
期刊论文
Research progress on ultra-precision machining technologies for soft-brittle crystal materials
Hang GAO,Xu WANG,Dongming GUO,Yuchuan CHEN
期刊论文
The effect of hierarchical single-crystal ZSM-5 zeolites with different Si/Al ratios on its pore structure
Yuexin Hou, Xiaoyun Li, Minghui Sun, Chaofan Li, Syed ul Hasnain Bakhtiar, Kunhao Lei, Shen Yu, Zhao Wang, Zhiyi Hu, Lihua Chen, Bao-Lian Su
期刊论文
Crystal modification of rifapentine using different solvents
Kun ZHOU, Jun LI, Jianhong LUO, Dongsheng ZHENG,
期刊论文
Crystal-to-crystal transformation from the triclinic to the cubic crystal system by partial desolvation
Qianqian Guo, Irmgard Kalf, Ulli Englert
期刊论文
Effect of hierarchical ZSM-5 zeolite crystal size on diffusion and catalytic performance of n-heptane
Shuman Xu, Xiaoxiao Zhang, Dangguo Cheng, Fengqiu Chen, Xiaohong Ren
期刊论文
Theoretical insights into influence of additives on sulfamethoxazole crystal growth kinetics and mechanisms
期刊论文
Polymorphism and crystal transformation of penicillin sulfoxide
Dingding JING, Yongli WANG, Zhijian CHEN, Lina ZHOU, Jingkang WANG
期刊论文