共查询到20条相似文献，搜索用时 15 毫秒
1.
Tae Min Choi Gun Ho Lee Young‐Seok Kim Jin‐Gyu Park Hyerim Hwang Shin‐Hyun Kim 《Advanced materials (Deerfield Beach, Fla.)》2019,31(18)
Colloidal particles with a repulsive interparticle potential spontaneously form crystalline lattices, which are used as a motif for photonic materials. It is difficult to predict the crystal arrangement in spherical volume as lattices are incompatible with a spherical surface. Here, the optimum arrangement of charged colloids is experimentally investigated by encapsulating them in double‐emulsion drops. Under conditions of strong interparticle repulsion, the colloidal crystal rapidly grows from the surface toward the center of the microcapsule, forming an onion‐like arrangement. By contrast, for weak repulsion, crystallites slowly grow and fuse through rearrangement to form a single‐crystal phase. Single‐crystal structure is energetically favorable even for strong repulsion. Nevertheless, a high energy barrier to colloidal rearrangement kinetically arrests the onion‐like structure formed by heterogeneous nucleation. Unlike the isotropic onion‐shaped product, the anisotropic single‐crystal‐containing microcapsules selectively display—at certain orientations but not others—one of the distinct colors from the various crystal planes. 相似文献
2.
Ye Hun Choi;Jiwoo Lee;Esther Amstad;Shin-Hyun Kim; 《Small (Weinheim an der Bergstrasse, Germany)》2024,20(20):2309512
Colloids self-organize into icosahedral clusters composed of a Mackay core and an anti-Mackay shell under spherical confinement to minimize the free energy. This study explores the variation of surface arrangements of colloids in icosahedral clusters, focusing on the determining factors behind the surface arrangement. To efficiently assemble particles in emulsion droplets, droplet-to-droplet osmotic extraction from particle-laden droplets to salt-containing droplets is used, where the droplets are microfluidically prepared to guarantee a high size uniformity. The icosahedral clusters are optimally produced during a 24-h consolidation period at a 0.04 m salt concentration. The findings reveal an increase in the number of particle layers from 10 to 15 in the icosahedral clusters as the average number of particles increases from 3300 to 11 000. Intriguingly, the number of layers in the anti-Mackay shells, or surface termination, appears to more strongly depend on the sphericity of the clusters than on the deviation in the particle count from an ideal icosahedral cluster. This result suggests that the sphericity of the outermost layer, formed by the late-stage rearrangement of particles to form an anti-Mackay shell near the droplet interface, may play a pivotal role in determining the surface morphology to accommodate a spherical interface. 相似文献
3.
Xiaoxuan Zhang Lingyu Sun Yunru Yu Yuanjin Zhao 《Advanced materials (Deerfield Beach, Fla.)》2019,31(51)
Ferrofluids, also known as ferromagnetic particle suspensions, are materials with an excellent magnetic response, which have attracted increasing interest in both industrial production and scientific research areas. Because of their outstanding features, such as rapid magnetic reaction, flexible flowability, as well as tunable optical and thermal properties, ferrofluids have found applications in various fields, including material science, physics, chemistry, biology, medicine, and engineering. Here, a comprehensive, in‐depth insight into the diverse applications of ferrofluids from material fabrication, droplet manipulation, and biomedicine to energy and machinery is provided. Design of ferrofluid‐related devices, recent developments, as well as present challenges and future prospects are also outlined. 相似文献
4.
Feika Bian Lingyu Sun Lijun Cai Yu Wang Yuetong Wang Yuanjin Zhao 《Small (Weinheim an der Bergstrasse, Germany)》2020,16(9)
Colloidal crystals are of great interest to researchers because of their excellent optical properties and broad applications in barcodes, sensors, displays, drug delivery, and other fields. Therefore, the preparation of high quality colloidal crystals in large quantities with high speed is worth investigating. After decades of development, microfluidics have been developed that provide new choices for many fields, especially for the generation of functional materials in microscale. Through the design of microfluidic chips, colloidal crystals can be prepared controllably with the advantages of fast speed and low cost. In this Review, research progress on colloidal crystals from microfluidics is discussed. After summarizing the classifications, the generation of colloidal crystals from microfluidics is discussed, including basic colloidal particles preparation, and their assembly inside or outside of microfluidic devices. Then, applications of the achieved colloidal crystals from microfluidics are illustrated. Finally, the future development and prospects of microfluidic‐based colloidal crystals are summarized. 相似文献
5.
《Advanced Materials Technologies》2018,3(4)
The human quest for beauty is manifested in numerous body decoration fashions such as makeups, tattoos, and stickers. The ancient “kirigami” art offers a variety of choices for sticker‐type body beautification, whereby with simple cutting, complex networks potential use as microfluidic channels and stretchable materials can be fabricated. Inspired by the fish‐scale pattern and kirigami art, a fish‐like wearable biosensor is designed and fabricated. This highly stretchable, well‐aerated, disposable, and wearable fish sticker enables sweat collection, diagnostics, and motion monitoring. A structure of photonic crystals is integrated in the paper channels for fluorescence enhancement sensing of sweat lactic acid and urea, and a stretchable electronic paper network induced sensitive resistance changes during the movement. The sensor is amenable to a variety of applications, such as personal care and human–machine interaction. The combination of art and sensing also provides a pleasant‐looking solution for both health and beauty. 相似文献
6.
7.
8.
Flavia Fontana Joo P. Martins Giulia Torrieri Hlder A. Santos 《Advanced Materials Technologies》2019,4(6)
Nanotechnology holds the promise of bringing revolutionary therapeutic strategies into the clinic. However, an enormous fraction of the currently proposed nanotechnology‐based therapies suffers from lack of reproducibility, complexity, high costs, and scale‐up‐related issues. For these reasons, the research community is moving toward the miniaturization of biomaterials and fabrication methods. Customizable microfluidic‐based products have gained tremendous relevance in the development of biomedical technologies. This review provides an overview of different materials that can be used for the fabrication of microfluidic devices, as well as the other parameters influencing the production of biomaterials and biosensors. Moreover, several advanced microfluidic‐based technologies that are designed to overcome the current challenges of cancer, immunotherapy, and diabetes therapy, among others are described. Then, the pros and cons of microfluidics as alternative to conventional preparation methods, and the challenges of translating this technique to an industrial context are highlighted. Overall, microfluidic technologies and their accessibility to the research community offer a set of exciting opportunities to bridge the development of innovative therapies and their commercialization in the foreseeable future. 相似文献
9.
Jin‐Woong Kim Daeyeon Lee Ho Cheung Shum David A. Weitz 《Advanced materials (Deerfield Beach, Fla.)》2008,20(17):3239-3243
10.
11.
单分散的胶体颗粒能自发排列成胶体阵列,其长程有序结构能获得许多特殊的性质.胶体阵列被用作制备可见光及近红外波长范围的光子晶体的基础.以其为模板制备的反蛋白石结构可拥有全光子禁带,为新一代光子器件开发和应用带来了希望.介绍了单分散胶体颗粒的主流制备方法,归纳总结了胶体阵列制备的几种方法和国内外最新的相关报道,简述了其在制备三维光子晶体领域的最新进展以及该领域国内外的研究进展. 相似文献
12.
13.
运用胶体化学法在乙醇介质中合成SiO2胶体球,将制得的样品在30℃下用双氧水浸泡处理48h.用扫描电子显微镜(SEM)、傅立叶红外光谱(FT-TR)、Zeta电位仪和标准氢氧化钠滴定法对其形貌、结构和表面电学性质进行分析.结果表明样品平均粒径为292nm,平均标准偏差小于5%;经双氧水浸泡处理后,SiO2胶体球表面羟基数目增多,在水溶液中的Zeta电位从-55.72mV提高到-63.26mV,表面电荷密度从0.19μC/cm2提高到0.28μC/cm2.通过垂直沉积法,在40℃和60%相对湿度条件下制备出有序性较好、密排结构的SiO2胶体晶体.在SEM下,观察到这种胶体晶体是面心立方(fcc)密排结构,其(111)晶面平行于基底.透射光谱表明,所制备的胶体晶体在(111)方向具有光子晶体的不完全带隙性质. 相似文献
14.
S. Furumi H. Fudouzi H. T. Miyazaki Y. Sakka 《Advanced materials (Deerfield Beach, Fla.)》2007,19(16):2067-2072
15.
16.
17.
18.
Chunxiao Wu John Selberg Brian Nguyen Pattawong Pansodtee Manping Jia Harika Dechiraju Mircea Teodorescu Marco Rolandi 《Small (Weinheim an der Bergstrasse, Germany)》2020,16(6)
A balanced concentration of ions is essential for biological processes to occur. For example, [H+] gradients power adenosine triphosphate synthesis, dynamic changes in [K+] and [Na+] create action potentials in neuronal communication, and [Cl?] contributes to maintaining appropriate cell membrane voltage. Sensing ionic concentration is thus important for monitoring and regulating many biological processes. This work demonstrates an ion‐selective microelectrode array that simultaneously and independently senses [K+], [Na+], and [Cl?] in electrolyte solutions. To obtain ion specificity, the required ion‐selective membranes are patterned using microfluidics. As a proof of concept, the change in ionic concentration is monitored during cell proliferation in a cell culture medium. This microelectrode array can easily be integrated in lab‐on‐a‐chip approaches to physiology and biological research and applications. 相似文献
19.
20.