Colorimetric Determination Of Hydrogen Peroxide Based on Localized Surface Plasmon Resonance of Silver Nanoprisms Using a Microchannel Chip

Silver nanoprisms (AgNPrs) have unique optical phenomena due to their localized surface plasmon resonance that results in the extinction of light from the visible to the near-infrared spectral region. In this study, we propose the colorimetric determination of silver nanoprisms in microchannels using a smartphone camera. Image acquisition was performed by capturing an image of the colloidal solution of the silver nanoprisms in the microchannel using the transmitted light. Red, green, and blue chromaticity levels were extracted from the recorded images for further quantification of the silver nanoprisms. This technique was employed for the detection and colorimetric determination of hydrogen peroxide (H₂O₂). Good linearity between the change in the green chromaticity level and concentration of hydrogen peroxide was observed for values from 10 to 300?μM with an R² value of 0.9670. We anticipate that the developed methodology for the quantification of silver nanoprisms and hydrogen peroxide by monitoring the change in color in the images of transmitted light will enhance the development of simple, rapid, and reliable detection systems for quality control in the production of silver nanoprisms as well as in chemical sensor applications.     

Facial strategy for radical species through Ag(I)-mediated oxidation of the alkyl trifluoroborates

A rapid and highly efficient method for the radical formation using potassium alkylfluoroborates as radical precursor is devised and developed which conducts under relatively mild condition using silver(I) oxide as the oxidant. The observed silver mirror phenomenon hints at the fact that Ag₂O is the real oxidant. This approach effectively overcomes the drawbacks-stringent reaction conditions and poor tolerance of a variety of functional groups.     

Energy of the surface segregation of Ag atoms in Ag–Au alloys in an aqueous solution

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Surface characterization of medieval silver coins minted by the early Piasts: FT‐IR mapping and SEM/EDX studies

An investigation of a numismatic collection of silver denarii from the early Piast dynasty was conducted using Fourier‐transform infrared spectroscopy. The studied coins, minted between 995 and 1020 ad under the rules of Boleslaus the Brave and Mieszko II Lambert, belong to the collection of the National Museum in Kraków. Fourier‐transform infrared spectroscopy imaging and mapping have been used for recording a visual image of the surface chemistry based on vibrational spectra and accurately representing the distribution of chemical compounds, respectively. Additionally, scanning electron microscopy coupled to energy‐dispersive X‐ray analysis was used to study the surface topography of the coins and characterize their elemental composition. Differences in the distribution of the identified chemical compounds were detected in heterogeneous areas of the denarii. Corrosion effects, associated to many factors including the alloy composition, the metallographic structure, the manufacturing processes, and the environment were also observed and identified.     

振镜法测量等离子体离子温度

 离子温度是托卡马克等离子体一个重要参数，介绍了一套振镜扫描装置，该装置主要由0.5m单色仪和安装在出射狭缝前的振动的石英镜片组成，时间分辨率小于10ms，系统测量误差小于20eV。测量了HT-6M托卡马克CV(227.1nm)谱线的线形，并由谱线的多普勒展宽得出欧姆加热和离子回旋共振加热（ICRH）下的离子温度，结果表明ICRH期间离子温度由200eV升高到300eV。这套装置广泛应用在中小型托卡马克上。     

从运动镜面的反射谈起

用运动界面的边值关系推导运动镜面的反射定律，引出电磁波边值关系的协变性，对积分形式的Maxwell方程的协定性进行了讨论。     

多层膜软X光反射镜的研制

本文介绍了镍-碳多层膜软X光反射镜的设计与制造方法,特别是膜厚监控法.用俄歇谱仪分析了一个样品的剖面情况;对一些样品在1.54(?)的衍射特性和在软X光区的反射率进行了测量并与理论计算结果作了比较.     

二氧化钛光催化回收金属银离子

研究了硝酸银水溶液的二氧化钛光催化还原沉积反应。在空气和氩气气氛中。光催化还原银效率没有明显差别，甲醇存在也没有明显促进银的光催化还原。该反应在碱性条件下有较大的还原速率。在低银离子浓度时，光催化能完全还原银离子。     

储存环自由电子激光器与KrF激光驱动器的激光谐振腔光学膜系实验研究

惯性约束核聚变氟化氪激光驱动器与储存环自由电子激光器,虽然其激光产生机理完全不同,但是它们对于激光谐振腔光学膜系的要求却几乎完全相同.新研制的Al₂O₃/SiO₂/MgF₂“双氧化物+单氟化物”紫外光学膜系,在248nm中心波长处,它的光学透射率测量值为0.27%—0.71%,反射率的计算值为96.5%,其光谱带宽为22.6nm.在脉冲宽度为23ns的KrF激光照射下,它的抗激光损伤阈值达到(5.36±0.30)J/cm²,是可用于储存环紫外波长自由电子激光研究与数千焦耳数量级高能、高功率KrF激光驱动器研究的高破坏阈值紫外光学膜系.     

Ag/Si multilayers with nanometer sized particles of silver during annealing process

Thein situ low angle X-ray diffraction and transmission electron microscopy were used to monitor the interdiffusion characteristics as well as the microstructure in Ag/Si multilayers with modulated wavelength 7. 64 nm when annealing from 323 to 573 K. The interdiffusion mechanism of Ag/Si multilayers with immiscibility is different from that of other metal/Si multilayers which are miscible. Phase separation takes place at 323 K, then silicon atoms diffuse into silver sublayers through silver grain boundaries and separate silver sublayers into nanometer sized silver particles gradually at higher temperature. The mean size of silver particles is about 5 nm. The activation energy and frequency factor are determined to be 0.24 eV and 2.02 x⁻²⁰m²/s, respectively. An erratum to this article is available at .