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位错增殖 1

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Effects of seeding nucleation agent on geopolymerization process of fly-ash geopolymer

Lapyote PRASITTISOPIN, Issara SEREEWATTHANAWUT

《结构与土木工程前沿（英文）》 2018年 第12卷 第1期   页码 16-25 doi: 10.1007/s11709-016-0373-7

摘要： Geopolymer, an inorganic aluminosilicate material activated by alkaline medium solution, can perform as an inorganic adhesive. The geopolymer technology has a viability to substitute traditional concrete made of portland cement (PC) because replacing PC with fly ash leads to reduced carbon dioxide emissions from cement productions and reduced materials cost. Although fly ash geopolymer stimulates sustainability, it is slow geopolymerization reaction poses a challenge for construction technology in term of practicality. The development of increasing geopolymerization reaction rate of the geopolymer is needed. ?The purpose of this study is to evaluate seeding nucleation agents (NA) of fly ash geopolymer that can accelerate polymerization reactions such that the geopolymer can be widely used in the construction industry. Results from the present study indicate that the use of NA (i.e., Ca(OH) ) can be potentially used to increase geopolymerization reaction rate and improve performance characteristics of the fly ash geopolymer product.

关键词： fly ash     geopolymer     nucleation agent     portland cement replacement    

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Primary nucleation of lithium carbonate

Yuzhu SUN, Xingfu SONG, Jin WANG, Yan LUO, Jianguo YU

《化学科学与工程前沿（英文）》 2009年 第3卷 第1期   页码 73-77 doi: 10.1007/s11705-009-0091-y

摘要： A set of laser apparatus was used to explore the induction period and the primary nucleation of lithium carbonate. Results show that the induction period increases with the decrease of supersaturation, temperature and stirring speed. Through the classical theory of primary nucleation, many important properties involved in primary nucleation under different conditions were obtained quantitatively, including the interfacial tension between solid and liquid, contact angle, critical nucleus size, critical nuleation free energy etc.

关键词： lithium carbonate     primary nucleation     reactive crystallization     induction period    

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Numerical study and control method of interaction of nucleation and boundary layer separation in condensing

Liansuo AN , Zhi WANG , Zhonghe HAN ,

《能源前沿（英文）》 2009年 第3卷 第3期   页码 254-261 doi: 10.1007/s11708-009-0047-4

摘要： The spontaneous nucleation flow in turbine cascade was numerically studied. The model was implemented within a full Navier–Stokes viscous flow solution procedure and the process of condensation was calculated by the quadrature method of moments that shows good accuracy with very broad size distributions. Results were presented for viscous and inviscous flow, showing the influence of boundary layer separation and wake vortices on spontaneous nucleation. The results show that the degree of flow separation in wet steam flow is greater than that in superheated steam flow due to condensation shock and that the loss cannot be neglected. Furthermore, the impact of boundary layer separation and wake vortices on velocity profiles and its implications for profile loss were considered. The calculations showed that layer separation and wake vortices influence nucleation rate, leading to different droplet distributions. A method for controlling homogeneous nucleation and for reducing degree of flow separation in high-speed transonic wet steam flow was presented. The liquid phase parameter distribution is sensitive to the suction side profile of turbine cascade, which impacts the nucleation rate distribution leading to different droplet distributions and affects the degree of flow separation. The numerical study provides a practical design method for turbine blade to reduce wetness losses.

关键词： wet steam     two-phase flow     spontaneous condensation     numerical simulation     flow separation     profile loss    

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Nucleation and growth mechanism of cefodizime sodium at different solvent compositions

Xinwei ZHANG, Shudong ZHANG, Xiaodan SUN, Zequn YIN, Quanjie LIU, Xiwen ZHANG, Qiuxiang YIN

《化学科学与工程前沿（英文）》 2013年 第7卷 第4期   页码 490-495 doi: 10.1007/s11705-013-1350-5

摘要： The induction time of cefodizime sodium was measured in ethanol-water at different solvent compositions by the laser technology measurement. The results indicate that the solvent composition played an important role in the supersaturation and the nucleation process of cefodizime sodium solution. According to the modified classical nucleation theory, the nucleation and growth mechanism were identified. The correlation results show that heterogeneous nucleation dominated the nucleation process at lower supersaturation, where homogeneous nucleation is the most important mechanism at higher supersaturation. Based on the correlated results, the 2D mediated growth mechanism had the highest correlation coefficients ( ), so this mechanism was selected as the proper growth mechanism for cefodizime sodium.

关键词： cefodizime sodium     induction time     primary nucleation     growth mechanism    

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Interfacial induction and regulation for microscale crystallization process: a critical review

《化学科学与工程前沿（英文）》 2022年 第16卷 第6期   页码 838-853 doi: 10.1007/s11705-021-2129-8

摘要： Microscale crystallization is at the frontier of chemical engineering, material science, and biochemical research and is affected by many factors. The precise regulation and control of microscale crystal processes is still a major challenge. In the heterogeneous induced nucleation process, the chemical and micro/nanostructural characteristics of the interface play a dominant role. Ideal crystal products can be obtained by modifying the interface characteristics, which has been proven to be a promising strategy. This review illustrates the application of interface properties, including chemical characteristics (hydrophobicity and functional groups) and the morphology of micro/nanostructures (rough structure and cavities, pore shape and pore size, surface porosity, channels), in various microscale crystallization controls and process intensification. Finally, possible future research and development directions are outlined to emphasize the importance of interfacial crystallization control and regulation for crystal engineering.

关键词： interfacial crystallization     heterogeneous nucleation     supersaturation     micro/nanostructure     process control and intensification    

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Synthesis of crystals and particles by crystallization and polymerization in droplet-based microfluidic devices

Jingtao WANG, Jin ZHANG, Junjie HAN,

《化学科学与工程前沿（英文）》 2010年 第4卷 第1期   页码 26-36 doi: 10.1007/s11705-009-0292-4

摘要： The recent advances in crystallization and polymerization assisted by droplet-based microfluidics to synthesize micro-particles and micro-crystals are reviewed in this paper. Droplet-based microfluidic devices are powerful tools to execute some precise controls and operations on the flow inside microchannels by adjusting fluid dynamics parameters to produce monodisperse emulsions or multiple-emulsions of various materials. Major features of this technique are producing particles of monodispersity to control the shape of particles in a new level, and to generate droplets of diverse materials including aqueous solutions, gels and polymers. Numerous microfluidic devices have been employed to generate monodisperse droplets of range from nm to μm, such as T junctions, flow-focusing devices and co-flow or cross-flow capillaries. These discrete, independently controllable droplets are ideal microreactors to be manipulated in the channels to synthesize the nanocrystals, protein crystals, polymer particles and microcapsules. The generated monodisperse particles or crystals are to meet different technical demands in many fields, such as crystal engineering, encapsulation and drug delivery systems. Microfluidic devices are promising tools in the synthesis of micron polymer particles that have diverse applications such as the photonic materials, ion-exchange and chromatography columns, and field-responsive rheological fluids. Processes assisted by microfluidic devices are able to produce the polymer particles (including Janus particles) with precise control over their sizes, size distribution, morphology and compositions. The technology of microfluidics has also been employed to generate core-shell microcapsules and solid microgels with precise controlled sizes and inner structures. The chosen “smart” materials are sensitive to an external stimulus such as the change of the pH, electric field and temperature. These complex particles are also able to be functionalized by encapsulating nanoparticles of special functions and by attaching some special groups like targeting ligands. The nucleation kinetics of some crystals like KNO was investigated in different microfluidic devices. Because of the elimination of the interactions among crystallites in bulk systems, using independent droplets may help to measure the nucleation rate more accurately. In structural biology, the droplets produced in microfluidic devices provide ideal platforms for protein crystallization on the nanoliter scale. Therefore, they become one of the promising tools to screen the optimal conditions of protein crystallization.

关键词： core-shell     monodisperse     nucleation     Microfluidic     different technical    

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膜结晶过程强化与控制研究进展 Review

姜晓滨, 邵钰珊, 盛磊, 李培钰, 贺高红

《工程（英文）》 2021年 第7卷 第1期   页码 50-62 doi: 10.1016/j.eng.2020.06.024

摘要：

结晶是用于固体颗粒制备的基本分离技术，其中成核和生长过程的精确调控至关重要。目前，发展同时增强整个结晶过程的新型控制技术仍然面临巨大挑战。膜结晶（MCr）是一种新兴耦合技术，近年来取得了长足的进步，有望实现上述目标。本文综述了MCr的基本概念及其在结晶控制和过程强化中的应用前景，对MCr用的关键膜材料、过程控制机制以及基于多种混合膜和结晶工艺的优化策略进行简述。最后，概述了将MCr技术推广到工业应用的尝试，以及需要解决的问题和研究方向。

关键词： 膜结晶     成核     过程控制     过程强化    

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Progress in membrane distillation crystallization: Process models, crystallization control and innovative applications

Xiaobin Jiang, Linghan Tuo, Dapeng Lu, Baohong Hou, Wei Chen, Gaohong He

《化学科学与工程前沿（英文）》 2017年 第11卷 第4期   页码 647-662 doi: 10.1007/s11705-017-1649-8

摘要： Membrane distillation crystallization (MDC) is a promising hybrid separation process that has been applied to seawater desalination, brine treatment and wastewater recovery. In recent years, great progress has been made in MDC technologies including the promotion of nucleation and better control of crystallization and crystal size distribution. These advances are useful for the accurate control of the degree of supersaturation and for the control of the nucleation kinetic processes. This review focuses on the development of MDC process models and on crystallization control strategies. In addition, the most important innovative applications of MDC in the last five years in crystal engineering and pharmaceutical manufacturing are summarized.

关键词： membrane distillation crystallization     mathematics model     nucleation     separation     hybrid process    

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Preparation and properties of nano SiO2 core-shell structured additives and their nanocomposite with polypropylene

KE Yangchuan, SUN Mingzhuo, SONG Yanxin, YANG GuangFu

《化学科学与工程前沿（英文）》 2007年 第1卷 第1期   页码 76-80 doi: 10.1007/s11705-007-0016-6

摘要： To improve the performance of traditional nucleation additives and their compatibility with other additives, as well as to solve complex problems in practical applications, SiO precursors were reactively grafted in situ with the symmetrical hydroxyl groups of the nucleation agents. With this approach, the dissymmetrical part of the nucleation agents plays an important role. As a result, the prepared composite additive the nanoparticle precursor (NPP0) produces excellent results. The NPP0-PP composite has a transparency of over 93%, haze lower than 15%, and a heat distortion temperature (HDT) of 142?C, which is more than the 110?C of the pure PP matrix. In addition, it maintains over 90% of the mechanical properties with a deformation coefficient less than 1%. This indicates a strong nanoeffect.

关键词： deformation coefficient     distortion temperature     excellent     NPP0-PP     traditional nucleation    

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Ultrafast solid-liquid-vapor phase change of a thin gold film irradiated by femtosecond laser pulses and pulse trains

Jing HUANG, Yuwen ZHANG, J. K. CHEN, Mo YANG

《能源前沿（英文）》 2012年 第6卷 第1期   页码 1-11 doi: 10.1007/s11708-012-0179-9

摘要： Effects of different parameters on the melting, vaporization and resolidification processes of thin gold film irradiated by femtosecond pulses and pulse train were systematically studied. The classical two-temperature model was adopted to depict the non-equilibrium heat transfer in electrons and lattice. The melting and resolidification processes, which was characterized by the solid-liquid interfacial velocity, as well as elevated melting temperature and depressed solidification temperature, was obtained by considering the interfacial energy balance and nucleation dynamics. Vaporization process which leads to ablation was described by tracking the location of liquid-vapor interface with an iterative procedure based on energy balance and gas kinetics law. The parameters in discussion included film thickness, laser fluence, pulse duration, pulse number, repetition rate, pulse train number, etc. Their effects on the maximum lattice temperature, melting depth and ablation depth were discussed based on the simulation results.

关键词： melting     evaporation     nucleation dynamics     nanoscale heat transfer    

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Lamellar thickness transition of melt-crystallized polybuten-1 tetragonal phase: configurational change in chain folding directions

Motoi YAMASHITA

《化学科学与工程前沿（英文）》 2009年 第3卷 第1期   页码 26-32 doi: 10.1007/s11705-009-0002-2

摘要： Lamellar crystal thickness of isotactic polybutene-1 ( -PB1) have been investigated for crystallization in the melt over a wide range of crystallization temperature from 40°C to 90°C by small angle X-ray scattering experiments and density measurements. The crystal thickness demonstrates two linear dependences on inverse supercooling and a transition from one dependence to the other has been observed around = 65°C. Each of the two dependences obeys the nucleation theory in the high and low supercooling ranges, respectively. Chain folding free energy determined from the low supercooling range is larger than that determined from the high supercooling range. Possible mechanisms for the transition are discussed taking account of entropy of chain folding directions.

关键词： isotactic polybutene-1     tetragonal phase     crystal thickness     melt growth     chain folding     small angle X-ray scattering     nucleation theory     end surface free energy    

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用于制造高效低成本太阳能电池的单晶种铸造大型单晶硅 Article

Bing Gao,Satoshi Nakano,Hirofumi Harada,Yoshiji Miyamura,Takashi Sekiguchi,Koichi Kakimoto

《工程（英文）》 2015年 第1卷 第3期   页码 378-383 doi: 10.15302/J-ENG-2015032

摘要：

为了能以低成本生产优质大型单晶硅，笔者提出了单晶种铸造技术。这项技术的实施，必须解决两个问题，即坩埚壁上的多晶成核问题和晶体内的位错增殖问题。在本文中，笔者尝试通过数值分析法来解决这两个问题。根据数值分析得出的优化熔炉结构和工况进行了实验，在实验中采用单晶种铸造技术来生长单晶硅。实验结果表明，该技术远优于常用的高性能多晶和准单晶铸造技术。

关键词： 单晶种铸造     单晶硅     多晶成核     位错增殖     多晶硅    

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标题 作者 时间 类型 操作

Effects of seeding nucleation agent on geopolymerization process of fly-ash geopolymer

Lapyote PRASITTISOPIN, Issara SEREEWATTHANAWUT

期刊论文

Primary nucleation of lithium carbonate

Yuzhu SUN, Xingfu SONG, Jin WANG, Yan LUO, Jianguo YU

期刊论文

Numerical study and control method of interaction of nucleation and boundary layer separation in condensing

Liansuo AN , Zhi WANG , Zhonghe HAN ,

期刊论文

Nucleation and growth mechanism of cefodizime sodium at different solvent compositions

Xinwei ZHANG, Shudong ZHANG, Xiaodan SUN, Zequn YIN, Quanjie LIU, Xiwen ZHANG, Qiuxiang YIN

期刊论文

Interfacial induction and regulation for microscale crystallization process: a critical review

期刊论文

Synthesis of crystals and particles by crystallization and polymerization in droplet-based microfluidic devices

Jingtao WANG, Jin ZHANG, Junjie HAN,

期刊论文

膜结晶过程强化与控制研究进展

姜晓滨, 邵钰珊, 盛磊, 李培钰, 贺高红

期刊论文

Progress in membrane distillation crystallization: Process models, crystallization control and innovative applications

Xiaobin Jiang, Linghan Tuo, Dapeng Lu, Baohong Hou, Wei Chen, Gaohong He

期刊论文

Preparation and properties of nano SiO2 core-shell structured additives and their nanocomposite with polypropylene

KE Yangchuan, SUN Mingzhuo, SONG Yanxin, YANG GuangFu

期刊论文

Ultrafast solid-liquid-vapor phase change of a thin gold film irradiated by femtosecond laser pulses and pulse trains

Jing HUANG, Yuwen ZHANG, J. K. CHEN, Mo YANG

期刊论文

Lamellar thickness transition of melt-crystallized polybuten-1 tetragonal phase: configurational change in chain folding directions

Motoi YAMASHITA

期刊论文

用于制造高效低成本太阳能电池的单晶种铸造大型单晶硅

Bing Gao,Satoshi Nakano,Hirofumi Harada,Yoshiji Miyamura,Takashi Sekiguchi,Koichi Kakimoto

期刊论文