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size control and its mechanism of SnAg nanoparticles

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Transactions of Nonferrous Metals Society of China 2014年第3期24卷 750-757页

作者：张卫鹏邹长东赵炳戈翟启杰高玉来上海大学微结构实验室上海200436 上海大学材料科学与工程学院上海200072 江苏省(沙钢)钢铁研究院张家港215625

Sn3.5Ag （mass fraction, %） nanoparticles were synthesized by an improved chemical reduction method at room temperature. 1,10-phenanthroline and sodium borohydride were selected as the surfactant and reducing agent, respectively. It was found that no obvious oxidation of the synthesized nanoparticles was traced by X-ray diffraction. In addition, the results show that the density of primary particles decreases with decreasing the addition rate of the reducing agent. Moreover, the slight particle agglomeration and slow secondary particle growth can result in small-sized nanoparticles. Meanwhile, the effect of surfactant concentration on the particle size can effectively be controlled when the reducing agent is added into the precursor at an appropriate rate. In summary, the capping effect caused by the surfactant molecules coordinating with the nanoclusters will restrict the growth of the nanoparticles. The larger the mass ratio of the surfactant to the precursor is, the smaller the particle size is.

关键词： Sn3.5Ag size control nanoparticles chemical reduction method

Fuzzy Mathematics for Raw Silk size control

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Journal of Donghua University(English Edition) 2008年第4期25卷 449-452页

作者：胡征宇俞海峰顾平 College of Material Engineering Soochow University

With photographing and experiments, this paper divides the cocoon layers into three categories according to their colors, establishes three-color membership function based on fuzzy mathematics, constructs fuzzy sets which satisfy the range of size control by using the ordinary set and attached frequency of threecolor cocoons combination, then achieves the ordinary sets of range of size control by choosing λ-cut. Under these ordinary sets, each end does duality relative level, then sets up relative matrix and overall sequence and finds the membership function to judge whether the size control is mormal.

关键词： color memberships function fuzzy setordinary set friction size control

INTERFACE CONSTRAINED GROWTH FOR size control NANOFABRICATION:MECHENISM AND EXPERIMENTS

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INTERFACE CONSTRAINED GROWTH FOR SIZE CONTROL NANOFABRICATIO...

control of Crystal size and Morphology of Calcium Carbonate Crystal Polymorphism

Asia Conference on Nanoscience and Nanotechnology Abstracts Book

作者： KUNJI CHEN KAI CHEN PEIGAO HAN LIN ZHANG XINFAN HUANG National Laboratory of Solid State Microstructures and department of Physics Nanjing University Nanjing 210093 China

＜正＞ Low-dimensional semiconductor systems, such as nanocrystalline silicon （nc-Si）, are currently being studied for the purpose of new applications in both nanoelectronic and photoelectronic devices. The size control of uniform nc-Si grains is the key technology for the device application. We propose a model on constrained growth in a-SiNx/a-Si:H/a-SiNx sandwich structures to make uniform nc-Si grains. The model of the constrained growth of nc-Si has been studied in accordance with the classical thermodynamic theory. Firstly, we discuss quantitatively the effect of the interface and shape of the nc-Si on the crystal growth in relation to the Gibbs tree energy. During the growth processes, when the grain shape transforms from sphere-like（size ＜ a-Si thickness） to disc-like shape（size ≥a-Si thickness）, the interfacial energy between nc-Si and a-SiNx will influence the grain growth which induces the increase of the nc-Si growth free energy and finally causes the growth to hah. From our model, we have theoretically determined the critical a-Si sublayer thickness of 34nm for the constrained crystallization growth and interpreted the increase of the crystallization temperature in the ultra thin a-Si sublayer.

关键词： nanofabrication size control constrained growth

来源： cnki会议评论

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Journal of Materials Science and Chemical Engineering 2021年第4期9卷 38-45页

作者： Wakana Nagaki Norihito Doki Masaaki Yokota Kazuo Yamashita Toshiji Kojima Toshiyuki Tanaka Department of Chemistry and Bioengineering Faculty of Engineering Iwate University Morioka Japan OKUTAMA KOGYO CO. LTD. Tokyo Japan

Calcium carbonate, the main component of lime, has been widely used in industry due to its stability and economy. Calcium carbonate has three types of crystalline polymorphism, calcite, aragonite and vaterite, each with different properties. Therefore, the control of crystal polymorphism is required for industrial applications. In addition, the control of crystal size and shape is similarly required for different applications. In this study, the effect of SrCO3 on the size control of fine aragonite-type calcium carbonate crystals by uniform urea precipitation and the effect of SrCO3 addition was investigated by adding solid strontium carbonate and dissolved strontium carbonate. The addition of solid strontium carbonate affected the crystal polymorphism and size of the calcium carbonate produced, depending on the properties of the solid particles and the amount of SrCO3 added. Experiments on the addition of dissolved SrCO3 showed that the supersaturation formation rate could be controlled to control the crystal polymorphism.

关键词： CaCO3 Aragonite SrCO3 Crystal Polymorphism size control

Rational design and structural regulation of near-infrared silver chalcogenide quantum dots

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Nano Research 2024年第12期17卷 10585-10606页

作者： Zhen-Ya Liu Wei Zhao Li-Ming Chen Yan-Yan Chen Zhi-Gang Wang An-An Liu Dai-Wen Pang College of Chemistry School of Medicine and Frontiers Science Center for Cell ResponsesFrontiers Science Centre for New Organic MatterTianjin Key Laboratory of Biosensing and Molecular RecognitionResearch Centre for Analytical SciencesNankai UniversityTianjin 300071China School of Chemical and Environmental Engineering Yancheng Teachers UniversityYancheng 224002China Haihe Laboratory of Sustainable Chemical Transformations Tianjin 300192China

Silver chalcogenides(Ag_(2)E;E=S,Se,or Te)quantum dots(QDs)have emerged as promising candidates for near-infrared(NIR)***,their narrow bandgap and small exciton Bohr radius render the optical properties of Ag_(2)E QDs highly sensitive to surface and size ***,the propensity for the formation of silver impurities and their low solubility product constants pose challenges in their controllable *** advancements have deepened our understanding of the relationship between the multi-hierarchical structure of Ag_(2)E QDs and their optical *** rational design and precise structural regulation,the performance of Ag_(2)E QDs has been significantly enhanced across various *** review provides a comprehensive overview of historical and current progress in the synthesis and structural regulation of Ag_(2)E QDs,encompassing aspects such as size control,crystal structure engineering,and surface/interface ***,it discusses outstanding challenges and potential opportunities in this *** aim of this review is to promote the custom synthesis of Ag_(2)E QDs for applications in biological imaging,and optoelectronics applications.

关键词： silver chalcogenides structural regulation size control crystal engineering surface and interface regulation

Performance of slotted pores in particle manufacture using rotating membrane emulsification

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Particuology 2009年第2期7卷 114-120页

作者： Nita Aryanti Richard A. Williams Institute of Particle Science and Engineering School of ProcessEnvironmental & Materials EngineeringUniversity of LeedsLeeds LS2 9JTUK

This paper addresses the use of different slotted pores in rotating membrane emulsification technology. Pores of square and rectangular shapes were studied to understand the effect of aspect ratio （1-3.5） and their orientation on oil droplet formation. Increasing the membrane rotation speed decreased the droplet size, and the oil droplets produced were more uniform using slotted pores as compared to circular geometry. At a given rotation speed, the droplet size was mainly determined by the pore size and the fluid velocity of oil through the pore （pore fluid velocity）. The ratio of droplet diameter to the equivalent diameter of the slotted pore increased with the pore fluid velocity. At a given pore fluid velocity and rotation speed, pore orientation significantly influences the droplet formation rate： horizontally disposed pores （with their longer side perpendicular to the membrane axis） generate droplets at double the rate of vertically disposed pores. This work indicates practical benefits in the use of slotted membranes over conventional methods.

关键词： Membrane emulsification Slotted pore Tubular membrane Rotating emulsification size control High throughput

Enhancing the catalytic efficiency of the Heck coupling reaction by forming 5 nm Pd octahedrons using kinetic control

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Nano Research 2015年第6期8卷 2115-2123页

作者： Ran Long Di Wu Yaping Li Yu Bai Chengming Wang Li Song Yujie Xiong Hefei National Laboratory for Physical Sciences at the Microscale Collaborative Innovation Center of Chemistry for Energy Materials School of Chemistry and Materials Science and National Synchrotron Radiation Laboratory University of Science and Technology ot China Hefei Anhui 230026 China

Heterogeneous catalysis occurs through a process of interfacial reactions; therefore, both surface facet and size control can increase catalytic efficiency. Octahedral Pd nanocrystals, enclosed by {111} facets, should be the ideal geometrical shape for Heck coupling reactions; however, it is challenging to synthesize 5 nm Pd octahedrons with a relatively uniform size distribution using existing capping-agent techniques. Here, we used palladium as a model system to investigate how the kinetics of atomic addition could be precisely controlled using a syringe pump. As a result, our method produced Pd octahedrons as small as 5 nm, which increased the catalytic efficiency of Heck coupling reactions while reducing the weight of catalyst used.

关键词： palladium facet control size control heck-type coupling reaction catalysis

Influence of Block Copolymer on Formation and Acid Resistant Properties of Hybrid CaCO_3 Particles

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Chemical Research in Chinese Universities 2009年第1期25卷 112-115页

作者： LI Xiao-dong HU Qiao-ling ZHAO Shi-fang SHEN Jia-cong Affiliated Stomatology Hospital Zhejiang University College of Medicine Hangzhou 310058 P. R. China Institute of Polymer Composite Zhejiang University Hangzhou 310027 P. R. China

Block copolymer polystyrene-b-poly（acrylic acid）（PS-b-PAA） was used as structural template for the synthesis of CaCO3 microparticles. Through this procedure, acid resistant hybrid CaCO3 micro- spheres were obtained. Acid resistant properties of this type of hybrid CaCO3 were studied. size measurement shows that the acid resistant properties of the hybrid particles are different in different solutions, such as HCl, EDTA, and H2SO4 solutions.

关键词： Amphiphilic block copolymer Hybrid particle size control Acid resistance

A Burst Assembly Method for Decreasing End-to-end Packet Delays in Optical Burst Switching Networks

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A Burst Assembly Method for Decreasing End-to-end Packet Del...