电致变色材料的变色机理及其研究进展

电致变色材料是目前公认的最有发展前途的智能材料之一。简要介绍了无机电致变色材料（如WO3、MoO3、NiO、IrOx等）和有机电致变色材料（如紫罗精、稀土酞花菁、聚苯胺等）这两种不同类型的变色材料及其研究现状，阐述了电致变色现象及其变色机理，并展望了其应用前景和发展方向。     

电致变色材料的变色机理及其研究进展

电致变色材料是目前公认的最有发展前途的智能材料之一.简要介绍了无机电致变色材料(如WO3、MoO3、NiO、IrOx等)和有机电致变色材料(如紫罗精、稀土酞花菁、聚苯胺等)这两种不同类型的变色材料及其研究现状,阐述了电致变色现象及其变色机理,并展望了其应用前景和发展方向.     

某型导弹表面漆层变色原因分析

某型导弹表面漆层发生了变色.通过模拟试验、光泽度测试及化学成分定量分析等方法,对漆层变色的原因进行了分析.结果表明:导弹包装箱所用的丁腈橡胶垫块在一定压力下与导弹漆层接触时,邻苯二甲酸二丁酯和N-苯基-1萘胺从橡胶垫块中渗出,对漆层产生污染,导致漆层变色和光泽度下降;增加水分后试样的污染程度和光泽度下降幅度更大,说明橡...     

铝合金表面刷镀银及防银变色工艺

介绍了铝基材上刷镀银工艺、预镀工艺及防银变色工艺,并对铝镀银层的性能进行了检测评定.     

热致变色材料的变色机理及其在智能包装中的应用

热致变色材料是一种能够随温度变化而改变颜色的智能材料.对热致变色材料的分类进行了梳理;对可逆和不可逆热致变色材料的变色机理进行了归纳总结;对热致变色材料在温度监测、食品新鲜度检测和防伪检测中的应用进行了介绍;最后指出了热致变色材料研究发展的方向.     

新型感温变色塑料导爆管及其性能?

对一种新型导爆药及由其拉制成的新型变色导爆管进行了相关性能研究。采用起爆药SY(三乙烯二胺乙二胺高氯酸共晶)作为导爆药的主成分,提高了起爆感度与安全性。该导爆药配比为w(SY):w(变色粉):w(Al)=88:9:3;以感温变色粉作为新型变色剂,实现激发前后导爆管颜色由有色到无色的变化,从而对导爆管的使用情况进行鉴别,同时使得导爆管的回收较传统导爆管更为便捷;由于主成分为爆轰威力更小的起爆药,对高温下导爆管易穿孔的矛盾有一定的缓解,同时爆速稳定,满足国标大于1 600m/s的要求。     

有机敏感变色功能材料的研究

综述了有机敏感变色材料的基本类型,探讨了材料的各种变色效应光致变色,热致变色,电致变色和压致变色等的内在关联,总结了有机敏感变色材料的基本分子结构类型并讨论了分子结构与敏感变色性质之间的关系。     

溴甲酚绿-碱土金属离子-十六醇热变色复配物制备及热变色性

制备了溴甲酚绿－碱土金属离子一十六醇热变色复配物。改变原料的配比可以得到一系列不同变色温度的复配物,该热变色复配物具有可逆性好、变色迅速敏锐、变色温度低、稳定性好等特点。用ＵＶ－Ｖｉｓ、ＤＳＣ对复配物的热变色性进行了研究。     

溅射氧化镍薄膜的电致变色特性

本文采用直流反应溅射获得了具有良好电色特性的ＮｉＯｘ薄膜。薄膜的电色特性强烈地受到制备条件的影响，在低溅射电压和高溅射压力下制得的薄膜电色效果最佳。典型的ＮｉＯｘ电色薄膜厚２００ｎｍ，可见光透过率变化范围在６３２．８ｎｍ处可达４８％，着色及退色响应时间为５～１０ｓ。Ｘ射线衍射表明薄膜呈非晶态。ＸＰＳ显示Ｎｉ￣（３＋）在电色过程中起着色心作用。红外反射谱证实电色过程有ＯＨ基的参与。     

载银无机抗菌剂变色抑制剂研发现状

介绍了载银无机抗菌剂变色抑制剂如甲基苯并三唑、天然水滑石和合成水滑石等的研发现状     

Packaging for freshness and the prevention of discoloration of fish fillets

Fillets of various kinds of fish are currently packed in thin films (e.g. polyvinyl chloride) for sale at supermarkets; however, these fillets are not necessarily fresh or of good quality. Packed fillets must be certified for safety, freshness and quality, because sensory judgement is difficult. In order to understand how the freshness and colour of red fish meat can be retained, the methods of packaging were examined. It was known that for freshness the packed fillets must be kept at a low temperature, but discoloration of red meat could not be prevented by this alone. However, discoloration of red-meat fish, such as yellowtail and oceanic bonito, can be prevented by packing with nitrogen gas (N₂).     

金膜表面聚丙烯酰吡咯膜的结构和表面形貌研究

研究了一种拟用于SPR生物传感器的生物材料.为此,首先在金膜表面制备聚丙烯酰吡咯膜,然后对膜的结构和表面形貌进行了研究.其中,制备聚丙烯酰吡咯(PAP)的方法是以丙烯酰氯和吡咯钾盐合成丙烯酰吡咯,然后以偶氮二异丁腈(AIBN)为引发剂,进行自由基聚合;金膜表面制备PAP膜的方法是:PAP溶于N,N-二甲基甲酰胺(DMF),然后旋涂到金膜上;最后,涂膜表面与吡咯在三氯化铁溶液中化学法聚合,形成聚合吡咯层.红外光谱可以看出,所得聚合物物质就是需要的产品;AFM非原位表面形貌图像和三维立体形貌图上显示涂膜覆盖了金膜表面原有的小孔,表面粗糙度比纯金膜增大.     

Quantitative study of protein coronas on gold nanoparticles with different surface modifications

Protein coronas provide the biological identity of nanomaterials in vivo. Here we have used dynamic light scattering （DLS） and transmission electron microscopy （TEM） to investigate the adsorption of serum proteins, including bovine serum albumin （BSA）, transferrin （TRF） and fibrinogen （FIB）, on gold nanoparticles （AuNPs） with different surface modifications （citrate, thioglycolic acid, cysteine, polyethylene glycol （PEG, Mw = 2 k and 5 k））. AuNPs with PEG（5 k） surface modification showed no protein adsorption. AuNPs with non-PEG surface modifications showed aggregation with FIB. AuNPs with citrate and thioglycolic acid surface modifications showed 6-8 nm thick BSA and TRF coronas （corres- ponding to monolayer or bilayer proteins）, in which the microscopic dissociation constants of BSA and TRF protein coronas are in the range of 104 to 104 M.     

Computer simulation of surface diffusion of copper, silver and gold

The binding energies to copper, silver and gold (111) surfaces of self-atom clusters have been calculated. The activation energies of motion of these ad-atom clusters, vacancies and divacancies on copper, silver and gold (111) surface, and of the conversion of ad-atom clusters on (111) and (100) have been calculated by use ofn-body embedded atom potentials and molecular dynamics.     

The surface chemistry and stability of gold nanoparticles prepared using methanol extract of Eucalyptus camaldulensis

The development of nontoxic, clean techniques for synthesising metal nanoparticles such as gold has attracted increasing attention in recent years. Many reports have been published about the synthesis of gold nanoparticles using plant extracts. However, the stability of these prepared gold nanoparticles has not been investigated. In this research, the stability of gold nanoparticles prepared by Eucalyptus camaldulensis was investigated at different temperatures (4°C, 25°C and 45°C) for 8 weeks. Transmission electron microscopy and visible absorption spectroscopy confirmed the stability of gold nanoparticles during the storage period at the mentioned condition. In addition, Fourier transform–infrared spectroscopy was used to investigate the surface chemistry of gold nanoparticles prepared by the methanol extract of E. camaldulsis. The carboxyl group was characterised on the surface of the gold nanoparticles, and this functional group may have a critical role in the stability of gold nanoparticles prepared by the mentioned plant extract at different conditions. This functional group can be used for drug delivery of amino derivative drugs using gold nanoparticles.     

无捕收剂浮选提高金矿回收率试验研究

为建设环保矿山并提高金矿回峰率,进行了无捕收剂浮选的试验研究。对磨矿细度、调整剂用量、硫化钠用量、起泡剂用量等条件进行了研究。结果表明,采用无捕收剂浮选工艺,在原矿金品位16．75g／t,磨矿细度细度-0．074mm占60％、硫化钠用量600克／吨,2#油用量234．8g／t、浮选时间24min的情况下,可获得金精矿平均品位45．96g／t、回收率96．33％的技术指标。比选矿厂原生产指标（92％左右）提高了4％以上的回收率。     

The effect of size and shape of gold nanoparticles on thin film properties

This work describes the properties of gold nanoparticles (AuNPs) thin film on silicon (Si) substrates. The AuNPs can be divided into two major shapes: gold nanospheres (AuNSs) and gold nanorods (AuNRs). Two sizes of AuNSs (15 nm and 30 nm) and three aspect ratios of AuNRs (3.12, 3.39 and 3.60) were synthesised using the seeding-growth method. The AuNPs produced were deposited on Si substrates by using a spin-coating method followed by heat treatment at 200 °C. The number of AuNPs coatings varied as one, three and five coating depositions, respectively. From the field emission scanning electron microscopy, the AuNPs were uniformly distributed on the Si substrate surface. The AuNPs distribution increased with increasing number of AuNPs coating. Various deposited AuNPs with different shapes and sizes were analysed using current–voltage (I–V) measurement in light–dark conditions. The results showed that the resistance of samples became lower under light condition as the number of AuNPs coatings increased on the Si substrate due to the large amount of AuNPs particles, which had better properties in absorbing and scattering the light intensity. Among these samples, five-coating depositions of 15 nm AuNSs and 3.12 aspect ratio of AuNRs thin films gave the best sensitivity in light–dark condition. The higher sensitivity implied the better sensing and recovery properties since it can amplify a small signal from the same light source power/intensity.     

Convective assembly of linear gold nanoparticle arrays at the micron scale for surface enhanced Raman scattering

A convective assembly technique at the micron scale analogous to the writing action of a “pipette pen” has been developed for the linear assembly of gold nanoparticle strips with micron scale width and millimeter scale length for surface enhanced Raman scattering (SERS). The arrays with interparticle gaps smaller than 3 nm are hexagonally stacked in the vicinity of the pipette tip. Variable numbers of stacked layers and clean surfaces of the assembled nanoparticles are obtained by optimizing the velocity of the pipette tip. The SERS properties of the assembled nanoparticle arrays rely on their stacking number and surface cleanliness.      

Electrochemical preparation of potassium gold cyanide

The essential requirements for the industrial preparation of potassium gold cyanide (pgc) are: (a) high rate of dissolution and (b) smooth and uniform dissolution. Employing galvanostatic and potentiostatic polarisation data and observations on the surface topography of anodes dissolved by both the techniques, it is shown that potentiostatic dissolution of gold in potassium cyanide at +0·345 V satisfies the above requirements.