Surface plasmon resonance-induced Ag-BaTiO3 composites for catalytic performance

Ferroelectric BaTiO₃ was combined with Ag nanoparticles for piezocatalytic and photocatalytic viewpoints. Microstructural characterization (X-ray diffraction and electron microscopy images) revealed that the Ag was successfully bounded with BaTiO₃. X-ray photoelectron spectrum also confirmed the presence of Ag. Further, its performance was examined for dye degradation under visible light (for photocatalysis) and ultrasonication (for piezocatalysis). In both the catalysis processes, there was a significant improvement in Ag-loaded BaTiO₃ sample-based catalytic reactions. Catalytic performance was evaluated for multiple cycles and was found consistent. Scavenger tests were also performed to understand catalytic reactions.     

Removal behavior and mechanism of silver from low concentration wastewater using cellulose aerogel modified by thiosemicarbazide

Due to the low concentration of silver in water, most of the cellulose adsorbents exhibited low removal efficiency, which greatly limited their practical applications. Herein, a cellulose aerogel modified by thiosemicarbamide (CAT) was fabricated for reducing and adsorbing silver ions from low concentration wastewater. The characterization results concluded that CAT owned a three-dimensional spongy structure with many circular microspheres and a better specific surface area (19.37 m² g⁻¹), as well as the functional groups of ─C═N⁺─H and ─(C═S)─N. The static batch adsorption experiments demonstrated that CAT could reached the maximum removal percentage of 94.94% and adsorption capacity of 42.12 mg g⁻¹ under the initial concentration of Ag(I) was 15 mg L⁻¹ and the pH value was 7. Meanwhile, the adsorption of Ag(I) on CAT was second-order reaction, and the Langmuir model could better fit the adsorption process. In addition, CAT exhibited wide pH values (1–9) adaptability and excellent adsorption performance for silver through electrostatic interaction, chelation, and reduction. This study probably provides a new method as well as important experimental data and theoretical reference for the removal of silver ions and other metals.     

PREPARATION OF SILVER POWDER FOR CONDUCTIVE PASTE

ＰＲＥＰＡＲＡＴＩＯＮＯＦＳＩＬＶＥＲＰＯＷＤＥＲＦＯＲＣＯＮＤＵＣＴＩＶＥＰＡＳＴＥＣｈａｉ，Ｌｉｙｕａｎ；Ｚｈｏｎｇ，Ｈａｉｙｕｎ；Ｗｕ，Ｈｕｉｙｕｎ（ＤｅｐａｒｔｍｅｎｔｏｆＮｏｎｆｅｒｒｏｕｓＭｅｔａｌｌｕｒｇｙ，ＣｅｎｔｒａｌＳｏｕｔｈＵｎ...     

AgNO3浓度对SPE电极镀覆纳米Ag的影响

采用浸渍还原法(I-R法)在Nafion离子膜上镀覆纳米Ag,并就AgNO3浓度对SPE电极镀覆纳米银的影响作了研究.研究表明采用I-R法可制得细致Ag镀层,有效增加Ag的分散度及电极的真实面积.在还原剂浓度为0.1mol·L-1,浸渍还原温度均为50℃及浸渍还原时间分别为40 min,60 min的条件下,调节浸渍液AgNO3浓度至3.5 mmol·L-1时,可获得致密、均匀的纳米级Ag/SPE电极.同时验证砂纸糙化的预处理有利于增加Ag的负载和附着力,有利于提高Ag催化层的有效面积.     

Ageing characteristics and microstructure of Al-4Mg-1.5Cu alloys containing silver and lithium

1　INTRODUCTIONTheroleoftraceelementsonageingofAlalloyshasbeenextensivelystudiedandhasbeenrecentlyre viewedbyPolmear ,RingerandPrabhuetal[14 ] .Itwasfoundthatthesmalladditionofsilvercanstimu lateenhancedagehardeningincertainAl Cu Mgal loys,andthiseffectisevidentforawiderangeofcompositionsselectedinthe (α +θ) ,(α +S)and (α+S +T ) phasefieldsoftheternary phasedia gram[57] .TheadditionofAgtoAl Cu MgalloyswithhighCutoMgratiosstimulatestheformationofanhexagonal shaped precipitate pha…     

A novel electroless silver depositing method for magnesium alloys

Depositing silver on magnesium alloy by both electroless plating and organic coatings was studied. The organic coating was made by immersing samples in organosilicon heat-resisting varnish. In this method the organic coating acts as interlayer between the substrate and silver film. When the reaction starts, silver deposits directly on the interlayer. X-ray diffraction and SEM analysis were used to determine the composition and morphology of the interlayer and silver film. The potentiodynamic polarization curves for corrosion studies of coated magnesium alloys were performed in a corrosive environment of 3.5% NaCl（mass fraction） at neutral pH （6.9）. The results indicate that compared with the substrate, the corrosion resistance of coated magnesium alloys increases greatly. Moreover, the method proposed in this work is environmentally friendly, non-toxic chemicals were used. In addition, it provides a new concept for the corrosion inhibition of magnesium alloys.     

Influence of Silver Doping on Photocatalytic Activity of Liquid-Flame-Sprayed-Nanostructured TiO2 Coating

Silver ion was added to liquid feedstock to deposit Ag⁺-doped-nanostructured TiO₂ photocatalytic coatings through liquid-flame spraying. The coating microstructure was characterized by x-ray diffraction (XRD). The photocatalytic performance of coatings was examined by photodegradation of acetaldehyde. The XRD analysis showed that the phase structure of coatings was not significantly influenced by the silver ion doping. However, a shift was found for XRD peaks of anatase TiO₂. The photocatalytic activity of the TiO₂ coatings increased and then decreased with the increase of dopant concentration. The photocatalytic activity of doped coatings was higher than that of pure TiO₂ coating, regardless of the dopant concentration. The enhancement of photocatalytic performance of doped coatings is attributed to co-doping of Ag⁺ ion and metallic Ag. This article is an invited paper selected from presentations at the 2007 International Thermal Spray Conference and has been expanded from the original presentation. It is simultaneously published in Global Coating Solutions, Proceedings of the 2007 International Thermal Spray Conference, Beijing, China, May 14-16, 2007, Basil R. Marple, Margaret M. Hyland, Yuk-Chiu Lau, Chang-Jiu Li, Rogerio S. Lima, and Ghislain Montavon, Ed., ASM International, Materials Park, OH, 2007.     

矿产资源开发利用及生态环境保护

分析了矿山企业在资源开发利用过程中所产生的生态环境问题和对环境所造成的影响，提出了解决这些问题的对策和措施。     

地质矿产资源勘查问题及对策

为了适应我国当前社会发展的需要,地质矿产资源的利用率越来越高。我国拥有大量的矿产资源,但由于长期不合理的勘探、开发和出口,使矿产企业遭受了巨大的损失。要促进我国矿产资源产业的发展及转型,就必须加强地质矿产勘察力度,同时保证合理开发。     

含银矿石的处理工艺技术

全面阐述国内外对含银矿石的处理工艺实践。包括①银的生产和银矿床,②银的工艺矿物学,③国外的含银矿石,④国内的含银矿石,⑤低品位银矿和尾矿中银的回收。