硬盘微晶玻璃基板的纳米金刚石抛光

应用经良好分散的纳米金刚石对硬盘微晶玻璃基板进行抛光,获得了亚纳米级表面(0.618nm)。分析了纳米金刚石抛光的行为,展望了纳米金刚石在超精密抛光领域的应用。     

Functionality is Key: Recent Progress in the Surface Modification of Nanodiamond

Nanoscale diamond has recently received considerable attention due to the various possible applications such as luminescence imaging, drug delivery, quantum engineering, surface coatings, seeding etc. For most of these fields a suitable surface termination and functionalization of the diamond materials are required. In this feature article we discuss recent achievements in the field of surface modification of nanoscale diamond including the establishment of a homogeneous initial surface termination, the covalent and non‐covalent immobilization of different functional moieties as well as the subsequent grafting of larger (bio)molecules onto previously functionalized nanodiamond.     

Luminescence of Nanodiamond Driven by Atomic Functionalization: Towards Novel Detection Principles

High biocompatibility, variable size ranging from ≈5 nm, stable luminescence from its color centers, and simple carbon chemistry for biomolecule grafting make nanodiamond (ND) particles an attractive alternative to molecular dyes for drug‐delivery. A novel method is presented that can be used for remote monitoring of chemical processes in biological environments based on color changes from photoluminescent (PL) nitrogen‐vacancy (NV) centers in ND. The NV luminescence is driven chemically by alternating the surface chemical potential by interacting atoms and molecules with the diamond surface. Due to the small ND size, the changes of the surface chemical potential modify the electric field profile at the diamond surfaces (i.e., band bending) and intermingle with the electronic NV states. This leads to changes in NV^?/NV° PL ratio and allows construction of optical chemo‐biosensors operating in cells, with PL visible in classical confocal microscopes. This phenomenon is demonstrated on single crystal diamond containing engineered NV centers and on oxidized and hydrogenated ND in liquid physiological buffers for variously sized ND particles. Hydrogenation of NDs leads to quenching of luminescence related to negatively charged (NV^?) centers and as a result produces color shifts from NV^? (638 nm) to neutral NV° (575 nm) luminescence. How the reduction of diamond size increases the magnitude of the NV color shift phenomena is modeled.     

炭黑填充丁苯/天然橡胶的电磁屏蔽性能

研究炭黑分别填充丁苯橡胶和丁苯/天然（50：50）并用橡胶的力学性能、导电性能和电磁屏蔽效能。对比发现,单组分丁苯橡胶体系的硬度、拉伸和撕裂性能均小于丁苯/天然橡胶并用体系。由于炭黑在并用体系中分布偏聚,体系的导电渗流阈值降低,相同炭黑含量时并用体系样品的体电阻率变小,电磁屏蔽效能增大。采用并用橡胶体系是减小复合材料导电渗流阈值,改善其力学性能的有效方法。     

Determination of Size,Morphology, and Nitrogen Impurity Location in Treated Detonation Nanodiamond by Transmission Electron Microscopy

Size, morphology, and nitrogen impurity location, all of which are all thought to be related to the luminescent properties of detonation nanodiamonds, are determined in several detonation nanodiamond samples using a combination of transmission electron microscopy techniques. Results obtained from annealed and cleaned detonation nanodiamond samples are compared to results from conventionally purified detonation nanodiamond. Detailed electron energy loss spectroscopy combined with model‐based quantification provides direct evidence for the sp³ like embedding of nitrogen impurities into the diamond cores of all the studied nanodiamond samples. Simultaneously, the structure and morphology of the cleaned detonation nanodiamond particles are studied using high resolution transmission electron microscopy. The results show that the size and morphology of detonation nanodiamonds can be modified by temperature treatment and that by applying a special cleaning procedure after temperature treatment, nanodiamond particles with clean facets almost free from sp² carbon can be prepared. These clean facets are clear evidence that nanodiamond cores are not necessarily in coexistence with a graphitic shell of non‐diamond carbon.     

Pushing the Functionality of Diamond Nanoparticles to New Horizons: Orthogonally Functionalized Nanodiamond Using Click Chemistry

Click chemistry is one of the most versatile means for the efficient grafting of larger units such as fluorescence labels or biomolecules onto the surface of nanoparticles. Here, a first study on the applicability of different strategies for the copper‐catalyzed azide–alkyne coupling of diamond nanoparticles and organic moieties is reported. Both thermally annealed nanodiamond and mechanically pretreated diamond nanoparticles of different origin can be modified with moieties carrying either azide or alkyne groups. Several organic units have been efficiently “clicked” onto these particles. The method is then applied for the bifunctional surface modification of nanodiamond leading to a material exhibiting carboxylic and alkyne groups at the same time. These can be addressed by orthogonal coupling linkers. A model material carrying two distinct fluorescent dyes is produced this way and shows the characteristic luminescence of both dyes. The findings open the way for the application of nanodiamond as multifunctional labels, drug delivery vehicles, and targeting agents in biomedical applications.     

Detonation Nanodiamond and Onion‐Like‐Carbon‐Embedded Polyaniline for Supercapacitors

The detonation nanodiamond is a versatile low‐cost nanomaterial with tunable properties and surface chemistry. In this work, it is shown how the application of nanodiamond (ND) can greatly increase the performance of electrochemically active polymers, such as polyaniline (PANI). Symmetric supercapacitors containing PANI‐ND nanocomposite electrodes with 3–28 wt% ND show dramatically improved cycle stability and higher capacitance retention at fast sweep rate than pure PANI electrodes. Contrary to other PANI‐carbon nanocomposites, specific capacitance of the selected PANI electrodes with embedded ND increases after 10 000 galvanostatic cycles and reaches 640 F g^?1, when measured in a symmetric two‐electrode configuration with 1 M H₂SO₄ electrolyte. The demonstrated specific capacitance is 3–4 times higher than that of the activated carbons and more than 15 times higher than that of ND and onion‐like carbon (OLC).     

Fluorescent Organic Glass with Unique Optical and Mechanical Properties

Conventional organic glasses such as molecular and polymeric glasses either lack processability or have ill‐defined properties. Here, a novel organic glass is reported having well‐defined fluorescent properties and high compatibility with various fabrication processes. The fluorescent organic glass (FOG) is synthesized by simply heating benzyl alcohol with a small amount of aqueous sulfuric acid. Owing to its outstanding optical properties, FOG is placed beyond the domain of conventional organic glasses in the Abbe diagram. Moreover, excellent rheological properties render it amenable to molding, blowing, and nanopatterning processes. Finally, based on extensive characterization, it is proposed that a FOG is composed of a 1,2,3,4‐tetraphenyl‐1,3‐butadiene core and poly(phenylene methylene) branches, which are responsible for molecular fluorescence and polymeric processability, respectively. The demonstration may contribute significantly to the development of organic glasses with unprecedented properties for various applications.     

新型显示器玻璃技术

新型显示器中使用的玻璃属于一种无碱玻璃,由于显示器的特性要求,这种玻璃在生产过程中具有投资高、难度大等特点,一般使用溢流下拉、槽口下拉、浮法等工艺。为了减少气泡等问题,通道一般采用铂铑合金等贵金属材料,在目前生产该产品的几个厂家中,其产品的特点是熔点高、比重轻、膨胀系数小、耐酸碱性能强。     

玻璃中介硅圆片键合研究

研究了玻璃中介圆片键合的方法.当采用低转化温度的玻璃粉末为中介玻璃层时,可在410℃实现强度较好的硅圆片键合,而如果将温度提高到430℃,键合强度可以达到4MPa.     

浅析通信建筑中玻璃幕墙的节能

在分析热对流、传导和辐射等热力学传导要素的基础上,介绍了中空玻璃、真空玻璃、吸热玻璃、热反射镀膜玻璃、低辐射镀膜玻璃、智能幕墙层等的节能效果,最后给出了玻璃幕墙上窗的结构形式及选材.     

Tailoring Mid-Gap States of Chalcogenide Glass by Pressure-Induced Hypervalent Bonding Towards the Design of Electrical Switching Materials

Phase change memory (PCM) and ovonic threshold switching (OTS) materials using chalcogenide glass are essential elements in advanced 3D memory chips. The mid-gap states, induced by the disorder and defects in the glass, are the physical mechanisms of the electrical switching behavior, while the origin of these trap states is still under debate and the medium-range clusters that break the global octet rule, such as over-coordinated atoms, are known to be responsible in various glass. Here, it is discovered that a large fraction of over-coordinated clusters fails to generate mid-gap states, which are probably caused by hypervalent bonding, a multi-centered covalent bond participated by delocalized lone-pair electrons. This is confirmed by the pressure-driven simulations of amorphous GeSe models, in which it is found that octahedral motifs and hypervalent bonds prevent the over-coordinated medium-range clusters from providing excessive electrons. In practical applications, compatible dopants can be used to change the number of hypervalent bonds, thus controlling the number of mid-gap states and consequently the performance of PCM and OTS materials. These results reveal the origin of mid-gap states in chalcogenide glasses, enabling extensive control in the development of pioneering electrical switching materials.     

橡胶测试仪器中的硫化曲线的实现

橡胶测试仪器在橡胶制品的生产过程特别是轮胎生产工艺中有着重要的作用,而硫化曲线是橡胶测试仪器中比较重要的参考标准之一,文中主要讨论了在橡胶测试仪器——硫化仪中的软件中的硫化曲线的实现方法。并且对3种实现方法进行了比较分析,在满足仪器要求的条件下进行了一定的处理,如贝塞尔曲线等,从而得出比较平滑的、视觉效果好的实时曲线并可以查询与打印。     

超声技术制备蒙脱土/天然橡胶纳米复合材料

采用超声技术制备了有机膨润土、钠基膨润土/天然橡胶复合材料，进行了力学性能和热氧老化性能测试，用TEM研究了粘土在橡胶中的分散结构及结合状态。结果表明，有机膨润土经过超声辐射后产生层间剥离，橡胶能够插层进入粘土层间，形成纳米分散结构的复合材料并具有较好的界面作用，从而提高材料的性能。而钠基膨润土难以产生有效剥离，与橡胶的结合较差；当有机膨润土的填充量为3%时，材料的拉伸强度即达到20mpa，老化后性能下降仅为35%。而钠基膨润土复合材料的拉伸强度为17MPa，老化后性能下降达68%。     

加成型硅橡胶在磁控管中的应用

本文介绍了加成型硅橡胶在磁控管生产中的应用和硅橡胶使用中的工艺细节对磁控管工作可靠性的影响,也说明了加成型硅橡胶的使用对于磁控管生产的积极作用。     

发泡橡胶在扬声器折环中的应用

介绍了近年来发泡材料在扬声器折环中应用的最新进展。阐述了发泡橡胶的原料选择,配方设计和生产工艺,由此获得表面光滑、泡腔精细的发泡橡胶。     

高非线性铋酸盐玻璃光纤的研究进展

一种具有极高非线性系数(γ=1 360 W-1·km-1)的新型非线性光纤--铋酸盐玻璃光纤近年来受到广泛关注.为此首先介绍了铋酸盐玻璃作为非线性材料的特点,综述了铋酸盐玻璃光纤作为高非线性光纤的研究历程和应用情况,最后对当前铋酸盐玻璃光纤研究中存在的问题进行了讨论.     

Detailed Balance Broken by Catch Bond Kinetics Enables Mechanical-Adaptation in Active Materials

Unlike nearly all engineered materials which contain bonds that weaken under load, biological materials contain “catch” bonds which are reinforced under load. Consequently, materials, such as the cell cytoskeleton, can adapt their mechanical properties in response to their state of internal, non-equilibrium (active) stress. However, how large-scale material properties vary with the distance from equilibrium is unknown, as are the relative roles of active stress and binding kinetics in establishing this distance. Through course-grained molecular dynamics simulations, the effect of breaking of detailed balance by catch bonds on the accumulation and dissipation of energy within a model of the actomyosin cytoskeleton is explored. It is found that the extent to which detailed balance is broken uniquely determines a large-scale fluid-solid transition with characteristic time-reversal symmetries. The transition depends critically on the strength of the catch bond, suggesting that active stress is necessary but insufficient to mount an adaptive mechanical response.     

彩色PDP用玻璃基板

本文讨论了彩色ＰＤＰ现用钠钙玻璃的热稳定性，指出由于这种玻璃在热处理过程中易变形和收缩，因而不适合作大面积彩色ＰＤＰ基板材料，介绍了彩色ＰＤＰ基板玻璃的制造方法和特点。最后介绍了日本旭硝子公司和美国康宁公司各自为彩色ＰＤＰ新开发的玻璃基板材料ＰＤ２００和ＣＳ２５。