毫米级单分散聚-α-甲基苯乙烯空心微球制备

采用汇聚式双重乳液发生器通过乳液微封装技术制备得到了毫米级单分散的聚--甲基苯乙烯空心微球。初步研究了各相流速对乳液形成过程、乳液直径及其分散度的影响。基于获得的单分散双重乳液,采用旋转蒸发方式固化得到了分散度小于3%、直径800~1200 m的聚--甲基苯乙烯空心微球。     

ZnO及其掺杂Mn纳米粒子的微乳液法合成

纳米材料的制备是纳米科学发展的基础,微乳液法与传统的制备方法相比具有明显的优势。本文用双微乳液混合法制备纳米ZnO粉末,通过实验从ZnSO4和NaCO3制备纳米粒子,同时采用在制备过程中掺杂Mn2+,讨论对其性质的改变的影响,并采用荧光发射分析和XRD表征。     

声化学新发展——纳米材料的超声制备

声空化所引发的特殊的物理，化学环境为制备具有特殊性能的新型材料提供了一条重要的途径，近年来，声化学处理已成为制备纳米材料的一种十分有效的技术，文章综合介绍了超声法制备纳米材料的主要类型，其中包括超声声解法，声化学还原法，超声共沉淀法，超声微乳液法等，并着重阐述了超声的作用原理和各种方法的特点。     

制备大直径无气泡聚苯乙烯空心微球

 高品质聚苯乙烯（PS）空心微球是惯性约束聚变（ICF）实验用多层塑料微球靶的重要芯轴,常由乳液技术制备。针对由乳液技术制备的PS微球壳壁内容易形成气泡而且大直径微球制备困难的问题,实验研究了对壳壁内存在的气泡以及消除方法和制备大直径PS微球的制备技术。     

多元丙烯酸酯泡沫微球的制备

 利用自行设计的三喷嘴乳粒发生器,实现了多元丙烯酸酯空心泡沫微球的可控连续制备。通过配制内层为水,中间层为多元丙烯酸酯单体溶液,外层为聚乙烯醇溶液的水/油/水乳液,在紫外光照射时,室温条件下成功快速地制备出粒径1.5~4.0 mm的多元丙烯酸酯泡沫微球。利用扫描电镜、X光机等测试手段对微球的形貌、表面特性进行了研究,结果显示：泡沫微球的高聚物骨架的折射率约为1.50,由大量分散的蜂窝微孔组成,蜂窝的直径不超过1 μm;多元丙烯酸酯泡沫微球的成活率高达93%,单分散性较好。     

纳米金属-聚苯乙烯复合材料制备

在2002年度的基础上，通过对纳米金属的表面改性，完成了纳米金属与聚苯乙烯的掺杂纳米金属在PS中的分散规律中研究，从实验过程中找出最佳掺杂配方和工艺，最后采用乳液法制备出纳米复合材料的空心微球。确定了最佳的纳米金属-聚苯乙烯复合材料的合成制备工艺。     

基于纳米材料封装的干涉型微纳光纤温度传感器

为了提高温度传感器的灵敏度,本文提出了基于纳米材料封装的干涉型微纳光纤温度传感器。该传感器通过熔融拉锥光敏光纤得到微纳光纤,用毛细管封装后填充高热光系数氮化硼分散液,并用紫外胶封装防止氮化硼挥发。当微纳光纤直径越小时,倏逝场越强,与外界环境的相互作用也会增强,但在灵敏度与稳定性之间平衡折中,实验中选择直径为12.3μm的微纳光纤。氮化硼分散液随温度变化折射率变化大,即对温度变化更敏感,通过传输光谱的漂移来检测温度响应。实验结果表明,随着温度的升高,透射光谱向波长更短的方向移动。无纳米材料封装的温度传感器灵敏度为-0.0297 nm/℃,氮化硼分散液封装之后灵敏度最高可达-0.2878 nm/℃,大约为无纳米材料封装传感器灵敏度的十倍左右。氮化硼分散液的浓度对实验温度灵敏度的影响十分微弱。该传感器具有结构小巧轻便,成本低,机械性高等优势,而且纳米材料封装可保护微纳光纤免受环境变化造成的形变以及外界杂质对传感部分的污染,保证实验的准确性。该传感器在温度传感领域具有重大发展潜力。     

微流控技术制备荧光纳米材料研究进展EI北大核心CSCD

荧光纳米材料因其独特的光学性能而被广泛用于传感、生物成像、离子检测等领域。微流控是一种能在微尺度上精确控制和操控流体的技术,近年来在有机合成、荧光材料制备、细胞检测、药物筛选等领域展现出重要的应用价值。本文以荧光纳米材料的制备为切入点,综述了微流控在该领域的研究进展。首先,根据反应器特征结构阐述了芯片微反应器、管式微反应器和离心式微反应器的特点及原理;进一步地,归纳整理了不同类型荧光纳米材料制备过程的典型例子,包括半导体纳米颗粒、碳点、钙钛矿纳米颗粒、稀土纳米材料、金属及氧化物复合纳米颗粒;最后,立足研究现状指出了该领域的挑战及研究方向。     

纳米α-Fe/PS复合材料的制备及其热力学性能研究

 采用油包水(W/O)的微乳液体系制备了粒度为20~100 nm的α Fe。对纳米Fe进行表面有机改性后分散到苯乙烯（St）单体中，得到分散均匀的Fe/St分散体系，用本体聚合的方法制备了纳米Fe/PS复合材料。利用XRD，TEM，FTIR，SEM及TG DSC分别研究了所得纳米Fe的性能、复合材料的结构、纳米Fe在PS中的分散情况以及掺杂量对纳米Fe/PS复合材料的热力学行为的影响。研究结果表明：增加纳米α-Fe的掺杂量能提高PS的降解率，降低降解温度，增大热分解的焓变。     

石蜡/水相变微乳液流变性能研究

低温石蜡/水相变微乳液作为一种潜热蓄冷流体,具有储能密度高、可泵送的特点。本文采用凝固点为9℃的石蜡作为分散相,在非离子表面活性剂的作用下制备石蜡/水相变微乳液,并通过自制的泵送实验平台研究微乳液在石蜡分散相呈固态、液态以及在固-液转变过程中的流变性能。实验结果表明,在不同温度情况下,微乳液在紊流区域经过水平管道的摩擦系数与雷诺数关系曲线与Metzner模型计算结果相符合。在流速为0.5~1.0 m·s~(-1)的情况下,石蜡质量分数为30%的微乳液在管道中引起的水头损失为水的水头损失的1.5~3倍。     

纳米La2(MoO4)3∶Eu/Fe3O4磁性荧光粉末的制备及用于指纹显现的研究

采用水热法和共沉淀法分别合成了纳米La₂(MoO₄)₃∶Eu荧光材料和纳米Fe₃O₄磁性材料,并利用透射电子显微镜、X射线衍射仪、荧光光谱仪表征纳米材料的形貌尺寸、晶体结构、荧光性能。经表征,纳米La₂(MoO₄)₃∶Eu荧光材料的微观形貌为片状结构,晶体结构为四方晶型,其发射光谱中出现了Eu3+的特征发射峰;纳米Fe₃O₄磁性材料的微观形貌为球形颗粒,晶体结构为立方晶型,并具有超顺磁性。然后,将以上两种纳米材料以一定比例混合均匀,制备了具有超顺磁性的La₂(MoO₄)₃∶Eu/Fe₃O₄纳米荧光粉末。经表征,该磁性纳米荧光粉末的微观形貌为片状结构与球形颗粒的混合,其发射峰位置未发生变化,而发光强度有所降低,但仍能够满足指纹显现的需要。最后,将制备的纳米磁性荧光粉末用于显现不同类型客体表面的潜在指纹。显现效果表明,对于光滑客体表面的指纹,使用磁性纳米荧光粉末与纳米荧光粉末的显现效果无明显差异;对于粗糙客体表面的指纹,使用磁性纳米荧光粉末能够清晰显现出指纹的细节特征,其显现效果明显优于普通纳米荧光粉末,并能够有效避免粉末扬尘现象。本研究制备的纳米磁性荧光粉末是一种理想的指纹显现材料,其指纹显现具有背景干扰低、显现效果好、适用范围广、无粉末扬尘等优点,在刑事案件现场具有广阔的应用前景。     

Chiral Ag and Au Nanomaterials Based Optical Approaches for Analytical Applications

Sensing of chiral compounds has gained great attentions for many decades. Chiral nanomaterials with a greater surface area, optical properties, and stability have however not been well realized in this field. Herein, strategies for the preparation of chiral Ag and Au nanomaterials are focused upon, including Ag and Au nanoparticles conjugated with chiral molecules with/without containing fluorophores, chiral nanoassemblies of Ag and Au nanoparticles, and chiral Ag and Au nanoclusters. The chirality of nanomaterials originates from their core and/or ligand, meanwhile that for nanoassemblies results from their complex spatial configuration. An emphasis is given to circular dichroism, colorimetry/UV–vis absorption, and fluorescence detection modes for sensing enantiomers and achiral analytes using the chiral Ag and Au nanomaterials. Several interesting examples for quantitation of DNA, proteins, peptides, drugs, and pollutants are provided to highlight their potential as sensitive and selective nanomaterials for enantiomer recognition and sensing of achiral analytes. Several important issues to be solved when using chiral nanomaterials for chiral recognition are specified. Some strategies for improving the sensitivity and selectivity of chiral nanomaterials for chiral recognition are suggested. The aim is to bring more attention to the potential of chiral nanomaterials for sensing important analytes such as chiral drugs.     

Occupational exposure limits for nanomaterials: state of the art

Assessing the need for and effectiveness of controlling airborne exposures to engineered nanomaterials in the workplace is difficult in the absence of occupational exposure limits (OELs). At present, there are practically no OELs specific to nanomaterials that have been adopted or promulgated by authoritative standards and guidance organizations. The vast heterogeneity of nanomaterials limits the number of specific OELs that are likely to be developed in the near future, but OELs could be developed more expeditiously for nanomaterials by applying dose–response data generated from animal studies for specific nanoparticles across categories of nanomaterials with similar properties and modes of action. This article reviews the history, context, and approaches for developing OELs for particles in general and nanoparticles in particular. Examples of approaches for developing OELs for titanium dioxide and carbon nanotubes are presented and interim OELs from various organizations for some nanomaterials are discussed. When adequate dose–response data are available in animals or humans, quantitative risk assessment methods can provide estimates of adverse health risk of nanomaterials in workers and, in conjunction with workplace exposure and control data, provide a basis for determining appropriate exposure limits. In the absence of adequate quantitative data, qualitative approaches to hazard assessment, exposure control, and safe work practices are prudent measures to reduce hazards in workers.     

纳米尺度下的局域场增强研究进展

金属纳米颗粒的等离激元共振引起的局域场增强效应,对显微成像、光谱学、半导体器件、非线性光学等诸多领域都具有极大的应用潜力。尤其是在光学纳米材料领域,通过亚波长金属纳米颗粒与电介质的组合引起局域场增强效应,提高了纳米材料的光学性能,并促进纳米材料在光学领域的应用。本文主要综述几种常见纳米结构所产生的局域场增强效应及其应用,详细介绍并总结了金属纳米材料的不同结构参数与局域场增强的关系及局域场增强在非线性光学、光谱学、半导体器件等领域的应用。未来,随着对金属纳米材料的研究愈发深入,局域场增强的应用将更加广泛,这将对诸多领域的发展产生重要影响。     

Nanohybridization of Low-Dimensional Nanomaterials: Synthesis,Classification, and Application

Nanomaterials have attracted much attention from academic to industrial research. General methodologies are needed to impose architectural order in low-dimensional nanomaterials composed of nanoobjects of various shapes and sizes, such as spherical particles, rods, wires, combs, horns, and other non specified geometrical architectures. These nanomaterials are the building blocks for nanohybrid materials, whose applications have improved and will continuously enhance the quality of the daily life of mankind. In this article, we present a comprehensive review on the synthesis, dimension, properties, and present and potential future applications of nanomaterials and nanohybrids. Due to the large number of review articles on specific dimension, morphology, or application of nanomaterials, we will focus on different forms of nanomaterials, such as, linear, particulate, and miscellaneous forms. We believe that almost all the nanomaterials and nanohybrids will come under these three categories. Every form or dimension or morphology has its own significant properties and advantages. These low-dimensional nanomaterials can be integrated to create novel nano-composite material applications for next-generation devices needed to address the current energy crisis, environmental sustainability, and better performance requirements. We discuss the synthesis, properties, and morphology of different forms of nanomaterials (building blocks). Moreover, we elaborate on the synthesis, modification, and application of nanohybrids. The applications of these nanomaterials and nanohybrids in sensors, solar cells, lithium batteries, electronic, catalysis, photocatalysis, electrocatalysis, and bio-based applications will be detailed. The time is now ripe to explore new nanohybrids that use individual nanomaterial components as basic building blocks, potentially affording additionally novel behavior and leading to new, useful applications. In this regard, the combination or integration of linear nanorods/nanowires and spherical nanoparticles to produce mixed-dimensionality, higher-level nanocomposites of greater complexity is an interesting theme, which we explore in this review article.     

High pressure structural phase transitions of TiO_2 nanomaterials

Recently, the high pressure study on the TiO_2 nanomaterials has attracted considerable attention due to the typical crystal structure and the fascinating properties of TiO_2 with nanoscale sizes. In this paper, we briefly review the recent progress in the high pressure phase transitions of TiO_2 nanomaterials. We discuss the size effects and morphology effects on the high pressure phase transitions of TiO_2 nanomaterials with different particle sizes, morphologies, and microstructures. Several typical pressure-induced structural phase transitions in TiO_2 nanomaterials are presented, including size-dependent phase transition selectivity in nanoparticles, morphology-tuned phase transition in nanowires, nanosheets,and nanoporous materials, and pressure-induced amorphization(PIA) and polyamorphism in ultrafine nanoparticles and TiO_2-B nanoribbons. Various TiO_2 nanostructural materials with high pressure structures are prepared successfully by high pressure treatment of the corresponding crystal nanomaterials, such as amorphous TiO_2 nanoribbons, α-PbO_2-type TiO_2 nanowires, nanosheets, and nanoporous materials. These studies suggest that the high pressure phase transitions of TiO_2 nanomaterials depend on the nanosize, morphology, interface energy, and microstructure. The diversity of high pressure behaviors of TiO_2 nanomaterials provides a new insight into the properties of nanomaterials, and paves a way for preparing new nanomaterials with novel high pressure structures and properties for various applications.     

A risk forecasting process for nanostructured materials, and nanomanufacturing

Nanomaterials exhibit novel properties that enable new applications ranging from molecular electronics to energy production. Proactive consideration of the potential impacts on human health and the environment resulting from nanomaterial production and use requires methods for forecasting risk associated with of these novel materials. However, the potential variety of nanomaterials is virtually infinite and a case-by-case analysis of the risks these materials may pose is not possible. The challenge of forecasting risk for a broad number of materials is further complicated by large degrees of uncertainty concerning production amounts, the characteristics and uses of these materials, exposure pathways, and a scarcity of data concerning the relationship between nanomaterial characteristics and their effects on organisms and ecosystems. A traditional risk assessment on nanomaterials is therefore not possible at this time. In its place, an evolving process is needed for analyzing the risks associated with emerging nanomaterials-related industries.In this communication, we propose that such a process should include the following six key features: (1) the ability to generate forecasts and associated levels of uncertainty for questions of immediate concern; (2) a consideration of all pertinent sources of nanomaterials; (3) an inclusive consideration of the impacts of activities stemming from nanomaterial use and production that extends beyond the boundaries of toxicology and include full life cycle impacts; (4) the ability to adapt and update risk forecasts as new information becomes available; (5) feedback to improve information gathering; and (6) feedback to improve nanomaterial design. Feature #6 implies that the potential risks of nanomaterials must ultimately be determined as a function of fundamental, quantifiable properties of nanomaterials, so that when these properties are observed in a new material, they can be recognized as indicators of risk. Thus, the required risk assessment process for nanomaterials addresses needs that span from urgent, short-term questions dealing with nanomaterials currently in commerce, to longer-term issues that will require basic research and advances in theory. In the following sections we outline issues surrounding each of these six features and discuss.     

Effects of Particle Size,Charge, Shape,Animal Disease State,and Sex on the Biodistribution of Intravenously Administered Nanoparticles

The relationship between nanoparticle size, charge, shape, and in vivo biodistribution is of great importance for the rational design and selection of intravenously administered nanoparticles. A resource that aids in the selection and design of nanomaterials for this purpose would be a valuable tool. Previous literature reviews have examined narrow categories of nanomaterials or have not statistically analyzed a broad range of nanomaterial literature. Here, data regarding the biodistribution of intravenously administered synthetic and organic nanomaterials in animal models from literature available in PubMed is collected. This work outlines the effect of nanoparticle size, charge, shape, animal sex, and animal disease status on biodistribution of intravenously administered nanomaterials. Particle size and charge are found to significantly and independently influence biodistribution to several organs. Finally, animal sex and disease state are observed to function as effect modifiers for biodistribution.     

一维Ga2O3纳米材料及其光电导性能研究进展

一维纳米材料以其特殊的物理和化学性质成为了现在纳米材料研究的热点.目前国内对一维纳米材料研究主要体现在两方面：一是一维纳米材料的制备;二是纳米材料的功能器件研究,如光电探测器、气敏探测器等.本文综述了一维Ga2O3纳米材料的几种常用的制备方法,包括工艺参数及生长机理,并简单介绍了Ga2O3光电导探测器的工作原理及最近的研究成果.     

Glow discharge plasma electrolysis for nanoparticles synthesis

There are many methods available to synthesize nanomaterials and the glow discharge plasma electrolysis is a novel and a green method in this category. It is seen that most of the papers are published after 2005 and the interest in it is growing due to its applicability in the industry for preparing nanomaterials at large scale. But, only few results are available yet and most of them are on metal nanoparticle preparation, so that more studies are needed to understand the nature of growth of the nanoparticles under glow discharge in liquid and its applicability in preparing semi-conductor nanomaterials. Many have tried many methods to prepare nanoparticles by the glow discharge and a review like this is the need of the time to understand its present status that helps to modify the present situation to a better one. This review classifies all the available methods of nanomaterials synthesis in liquid by glow discharge in to three and it is discussed in detail.