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Effect of Erbium Nanoparticles on Optical Properties of Zinc Borotellurite Glass System  [PDF]
Azlan Muhammad Noorazlan,Halimah Mohamed Kamari,Siti Shafinas Zulkefly,Daud W. Mohamad
Journal of Nanomaterials , 2013, DOI: 10.1155/2013/940917
Abstract: Erbium nanoparticles (NPs) doped zinc borotellurite glasses have been prepared by conventional melt-quenching technique with the chemical composition (where ). The structural properties of the prepared glasses were determined via X-ray diffraction (XRD) analysis and FTIR analysis. It was confirmed that the prepared glasses are amorphous. The bonding parameters of the glasses were analyzed by using FTIR analysis and were confirmed to be ionic in nature. The refractive index increases as the content of erbium NPs increases. The optical absorption spectra revealed that fundamental absorption edge shifts to longer wavelength as the content of erbium NPs increases. The value of band gap had been calculated and shown to be decreased with an increase content of erbium NPs. The Urbach energy was shown to be linearly increased with an increase content of erbium NPs oxides. 1. Introduction Rare-earth doped materials have made the largest interest to develop the photonic system for various applications with regard to their advance optical properties. Erbium oxide is one of the most potential candidates among the lanthanide group in the pursuit of photonic materials research. Erbium consists of trivalent electron which is known to be advantaged to fiber amplifier applications. Nowadays, special attention is paid to explore the optical behavior of the Er3+ ions due to its emission at 1.53?μm, which is ideal for applications in the field of optical data transmission [1]. The choice of a suitable host matrix is important to obtain the excellent optical properties. Tellurite oxide is known to be the best candidate among the heavy metal materials because of its unique optical and electrical properties. The compatibility and solubility of tellurite based glass to the other oxide glasses are the most excellent among the heavy metals. Recently, tellurite based glass has been used in several photonic devices such as precursors for infrared fibers and windows. Formation of pure tellurite oxide glass does not occur without contributions from external element. Borate oxide is known as the best choice to stabilize the glass formation due to its good rare earth ion solubility and hardness. The borate matrix possesses well defined gathering of BO3 triangles and BO4 tetrahedra to form stable borate groups such as diborate, triborate, and tetraborate [2]. Contributions of zinc oxide in the glass formation reduce the melting point and increases the glass forming ability. It has been reported that [3] the effect of zinc oxide decreases the optical energy gap and increase the
The Effect of Remelting on the Physical Properties of Borotellurite Glass Doped with Manganese  [PDF]
Syed Putra Hashim Syed Hashim,Haji Abdul Aziz Sidek,Mohamed Kamari Halimah,Khamirul Amin Matori,Wan Mohamad Daud Wan Yusof,Mohd Hafiz Mohd Zaid
International Journal of Molecular Sciences , 2013, DOI: 10.3390/ijms14011022
Abstract: A systematic set of borotellurite glasses doped with manganese (1– x) [(B 2O 3) 0.3(TeO 2) 0.7]- xMnO, with x = 0.1, 0.2, 0.3 and 0.4 mol%, were successfully synthesized by using a conventional melt and quench-casting technique. In this study, the remelting effect of the glass samples on their microstructure was investigated through density measurement and FT-IR spectra and evaluated by XRD techniques. Initial experimental results from XRD evaluation show that there are two distinct phases of glassy and crystallite microstructure due to the existence of peaks in the sample. The different physical behaviors of the studied glasses were closely related to the concentration of manganese in each phase. FTIR spectra revealed that the addition of manganese oxide contributes the transformation of TeO 4 trigonal bipyramids with bridging oxygen (BO) to TeO 3 trigonal pyramids with non-bridging oxygen (NBO).
Stability of properties in silver - lanthanum alloy  [PDF]
W.J. G?uchowski,Z.M. Rdzawski
Journal of Achievements in Materials and Manufacturing Engineering , 2007,
Abstract: Purpose: The objective of the work was to investigate changes in structure and properties of Ag+(0,5%wt)La alloy and its difference to the comparative Ag+(7,5%wt)Cu and pure Ag materials.Design/methodology/approach: Tests were made with samples obtained by melting and casting in inductive furnace. Further plastic deformation was provided by KOBO extrusion and drawing. The mechanical properties (at room temperature, elevated temperature and after annealing) and microstructure (by the optical, scanning and transmission electron microscopy) were examined.Findings: Analysis of the initial microstructure of these materials was made, and its evolution during deformation process was investigated with respect to the changes in the mechanical and electrical properties.Research limitations/implications: Significant changes in microstructure after extrusion were observed. Alloy with addition of lanthanum had an excellent electrical conductivity close to the conductivity of pure silver. Mechanical properties examination after annealing gave grounds to conclude that also this alloy had increased properties stability at elevated temperature.Practical implications: Alloy with addition of lanthanum after further investigations could be considered as a material for producing electric or electronic parts which are designed to work in environment of elevated temperature or with a risk of temperature changes.Originality/value: The paper shows properties stability in new designed silver alloy with addition of lanthanum. Wire made of this material could be easy produced with examined methods, without any annealing process. Having stable properties and excellent electrical conductivity this alloy could be considered as a material for producing advanced electrical or electronic equipment.
Preparation of Silver- and Zinc-Doped Mullite-Based Ceramics Showing Anti-Bacterial Biofilm Properties  [PDF]
Suhair Saleh,Mutasem O. Taha,Randa N. Haddadin,Duá Marzooqa,Hamdallah Hodali
Molecules , 2011, DOI: 10.3390/molecules16042862
Abstract: Zinc- and silver-doped mullite ceramic discs were prepared and tested as potentially resistant materials against bacterial adhesion and biofilm formation. Elemental analysis and X-ray diffraction studies showed that zinc ions were incorporated in the structural framework of the mullite, while silver ions remained outside the mullite crystal lattice, which allowed their slow (0.02 ppm/24 hours) leaching into the surrounding aqueous environment. In agreement with this behavior, silver-doped mullite showed potent resistance against surface attachment of Pseudomonas aeruginosa, while on the other hand, zinc-doped mullite failed to stop bacterial attachment.
LaZnB5O10, the first lanthanum zinc borate  [cached]
Zhi-Wei Jiao,Ru-Ji Wang,Xiao-Qing Wang,De-Zhong Shen
Acta Crystallographica Section E , 2010, DOI: 10.1107/s1600536809050922
Abstract: Lanthanum zinc pentaborate, LaZnB5O10, was synthesized by flux-supported solid-state reaction. It is a member of the LnMB5O10 (Ln = rare earth ion and M = divalent metal ion) structure type. The crystal shows a three-dimensional structure constructed from two-dimensional {[B5O10]5 }n layers with the lanthanum (coordination number nine) and zinc (coordination number six) ions filling in the interlayers.
Intermetallic combination of lanthanum and silver nanoparticles prepared by vacuum deposition
镧与真空沉积银纳米粒子的金属间化合

Xu Bei-Xue,Wu Jin-Lei,Hou Shi-Min,Zhang Xi-Yao,Liu Wei-Min,Xue Zheng-Quan,Wu Quan-De,
许北雪
,吴锦雷,侯士敏,张西尧,刘惟敏,薛增泉,吴全德

物理学报 , 2002,
Abstract: The tendency of intermetallic combination between silver and lanthanum is analyzed based on the Hume Rothery rule, and the possibility of forming intermetallic compounds between silver and lanthanum in vacuum deposition is analyzed according to the condition of vacuum deposition. The X ray photoelection spectroscopy method is used to analyze the thin films of silver and lanthanum formed by vacuum deposition. The results confirm the existence of intermetallic compounds between silver and lanthanum.
Spectroscopy of vanadium (III) doped gallium lanthanum sulphide chalcogenide glass  [PDF]
M. Hughes,R. J. Curry,H. Rutt,D. Hewak
Physics , 2014, DOI: 10.1063/1.2432280?
Abstract: Vanadium doped gallium lanthanum sulphide glass (V:GLS) displays three absorption bands at 580, 730 and 1155 nm identified by photoluminescence excitation measurements. Broad photoluminescence, with a full width half maximum (FWHM) of 500 nm, is observed peaking at 1500 nm when exciting at 514, 808 and 1064 nm. The fluorescence lifetime and quantum efficiency at 300 K were measured to be 33.4 us and 4 % respectively. From the available spectroscopic data we propose the vanadium ions valence to be 3+ and be in tetrahedral coordination The results indicate potential for development of a laser or optical amplifier based on V:GLS.
Lead and silver extraction from waste cake from hydrometallurgical zinc production
DUSAN D. STANOJEVIC,MILOS B. RAJKOVIC,DRAGAN V. TOSKOVIC,MILANA A. TOMIC
Journal of the Serbian Chemical Society , 2008,
Abstract: This paper presents the experimental results of the extraction of lead and silver from a lead–silver waste cake obtained in the process of hydrometallurgical zinc production. While controlling the pH value, the lead–silver cake was leached at a temperature close to boiling point in different concentrations of aqueous calcium chloride solutions. The experiments were performed applying different ratios between the mass of cake and the volume of the leaching agent under different durations of the process. It was concluded that at the optimal process parameters (pH 2.0–2.5; CaCl2 concentration, 3.6 mol dm-3; temperature, 95 °C; solid/liquid ratio, 1:5), the leaching efficiency of lead and silver could reach the approximate value of 94 %. Applying the same optimal process parameters, the method was applied to the leaching of a lead–silver cake in a magnesium chloride solution, but with significantly lower efficiencies. The results show that leaching of lead and silver in a calcium chloride solution could be a prospective method for increasing the recovery of lead and silver during hydrometallurgical zinc production.
Synthesis of Silver-Doped Zinc Oxide Nanocomposite by Pulse Mode Ultrasonication and Its Characterization Studies  [PDF]
T. Siva Vijayakumar,S. Karthikeyeni,S. Vasanth,Arul Ganesh,G. Bupesh,R. Ramesh,M. Manimegalai,P. Subramanian
Journal of Nanoscience , 2013, DOI: 10.1155/2013/785064
Abstract: The synthesis of silver-doped zinc oxide (Ag:ZnO) nanocomposite material was achieved using a simple chemical coprecipitation method, in which 0.2?M zinc chloride and 0.001?M silver nitrate coprecipitated with 25% ammonia solution by pulse mode dispersion using ultrasonicator. The obtained silvery white precipitate was dried overnight at 110°C in hot air oven, and the powder was collected. The resulted Ag:ZnO nanocomposite was structurally and optically characterized using various techniques. The X-ray diffraction (XRD) pattern clearly showed the presence of crystalline Ag:ZnO particles. Further, UV-Vis spectrophotometer and fourier transform infrared spectroscopy (FT-IR) results showed the presence of Ag:ZnO nanocomposite at specific wavelengths. The scanning electron microscopy (SEM) and transmission electron microscopy (TEM) analysis confirm that the synthesized Ag:ZnO nanocomposite material was truncated nanorod in shape and has 48 to 226?nm size in diameter. 1. Introduction Zinc oxide (ZnO) is an important industrial material, because it has an inorganic and semiconducting material with inherent properties that share its structure as wurtzite [1]. ZnO nanocomposite has attracted interest because of its optical properties. These particles are transparent to visible light, but they absorb UV-light. ZnO has attracted intensive research effort for its unique properties and versatile applications in transparent electronics, chemical sensors, and spin electronics [2–8]. A variety of metal oxides like zinc oxide, titanium dioxide (TiO2), and silicon dioxide (SiO2) and different techniques such as chemical coprecipitation [9, 10], sol-gel process [11, 12] chemical vapour deposition [13], thermal decomposition [14, 15], hydrothermal synthesis [16, 17], solid-state reaction [18], spray pyrolysis [19], vapour-liquid-solid method [20], and microemulsion precipitation [21–23] have been used so far. Hingorani et al. also reported the synthesis of ZnO nanoparticles (NPs) and it was the first study using reverse microemulsion in the early 1990s [24, 25]. Synthesis process of Ag:ZnO nanocomposite plays a key role in governing size, morphology, and its properties of nanocomposite through dispersion method (pulse mode), using ultrasonication [26]. The main objective of synthesis is to produce particles only in nanorod structure for various toxicity and biological application studies. There are different doping agents like P [27], N [28], As [29], Li [30], Sb [31–34], and Ag [35]. Among these, we have taken Ag as doping agent. Because the nature of Ag ions is simple
Growth of silver nanoclusters embedded in soda glass matrix  [PDF]
P. Gangopadhyay,P. Magudapathy,R. Kesavamoorthy,B. K. Panigrahi,K. G. M. Nair,P. V. Satyam
Physics , 2004, DOI: 10.1016/j.cplett.2004.03.055
Abstract: Temperature-controlled-growth of silver nanoclusters in soda glass matrix is investigated by low-frequency Raman scattering spectroscopy. Growth of the nanoclusters is ascribed to the diffusion-controlled precipitation of silver atoms due to annealing the silver-exchanged soda glass samples. For the first time, Rutherford backscattering measurements performed in this system to find out activation energy for the diffusion of silver ions in the glass matrix. Activation energy for the diffusion of silver ions in the glass matrix estimated from different experimental results is found to be consistent.
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