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Study on Characteristics of Gold Powder with Round Shape for Maki-e  [PDF]
Chieko Narita, Yutaro Shimode, Kazushi Yamada
Materials Sciences and Applications (MSA) , 2015, DOI: 10.4236/msa.2015.610086
Abstract: Maki-e is a traditional Japanese decorative technique that uses the natural lacquer Urushi and metal powders. Currently, there exist only two companies that manufacture metal powder for the purpose of Maki-e, and this research focuses on comparing the material characteristics of the gold powders with round shape manufactured by them. EDS (energy-dispersive X-ray spectroscopy) analysis, image analysis of particle shape before and after Maki-e processing, and color analysis of samples after Maki-e processing were carried out in this research. The study revealed that current gold powders with round shape had almost the same content ratio regardless of the manufacturing company and the powder diameter. In addition, spherical shape and irregular shape were observed in any gold powders, and the aggregates were observed in powder with increasing the powder diameter, while the shape of the aggregates differed with manufacturing companies. Therefore, it was indicated that the aggregates in the powder made by Asano Co., Ltd. had an influence on the particle diameter and its deviation after Maki-e processing. Moreover, the powder in Urushi resin has an influence on the Maki-e appearance because there is a color difference in polished powder, powder in Urushi resin, and Urushi resin.
Effect of Different Eggshell Powder on Appearance of Eggshell Maki-e  [PDF]
Yutaro Shimode, Chieko Narita, Atsushi Endo, Kazushi Yamada
Materials Sciences and Applications (MSA) , 2013, DOI: 10.4236/msa.2013.42016
Abstract:

The Maki-e technique with eggshell powder is one of techniques of Japanese traditional Urushi (Japanese lacquer) crafts. However, this technique is relatively new in the history of Maki-e, and there are no prior researches in terms of materials, structure, and properties. In this research, therefore we have aimed to evaluate the relationship between the eggshell powder sizes, dispersion, and color shade in Maki-e with eggshell powder. The difference between hen’s and quail’s eggshell characteristics and the effect of their powder particle size on appearance of eggshell Maki-e were discussed on the basis of the results of the particle size, circularity, particle number, and RGB value. As a result, it was found that the occupancy of the eggshell powder on the surface depends on not particle number but the particle size, whereas the whiteness of both eggshell powders depends on the particle size.

The Potential Impact of Biofield Energy Treatment on the Physical and Thermal Properties of Silver Oxide Powder
Mahendra Kumar Trivedi, Rama Mohan Tallapragada, Alice Branton, Dahryn Trivedi, Gopal Nayak, Omprakash Latiyal, Snehasis Jana
International Journal of Biomedical Science and Engineering , 2015, DOI: 10.11648/j.ijbse.20150305.11
Abstract: Silver oxide has gained significant attention due to its antimicrobial activities. The purpose of this study was to evaluate the impact of biofield energy treatment on the physical and thermal properties of silver oxide (Ag2O). The silver oxide powder was divided into two parts, one part was kept as control and another part was received Mr. Trivedi’s biofield energy treatment. The control and treated samples were analyzed using X-ray diffraction (XRD), differential scanning calorimetry (DSC), thermogravimetric analysis (TGA), and Fourier transform infrared (FT-IR) spectroscopy. The XRD diffractogram showed that the crystallite size of treated sample was significantly altered on the planes (200), (311), and (220) by 100, 150 and -25% respectively, with respect to control. The DSC result exhibited that the thermal energy required to decompose the silver oxide to silver and oxygen was altered from -12.47 to 71.58% in treated samples as compared to the control. TGA showed that the onset temperature of thermal degradation was reduced from 335°C (control) to 322.4°C. In addition, the rate of weight loss in treated sample was increased by 4.14% as compared to the control. Besides, the FT-IR did not show any alteration in absorption wavenumber of treated sample as compared to the control. Hence, the XRD, DSC and TGA data revealed that the biofield energy treatment has a significant impact on the physical and thermal properties of silver oxide powder. Therefore, the biofield energy treatment might improve the dissolution rate in formulation and bioavailability of treated silver oxide as compared to control.
Nanostructural Features of Silver Nanoparticles Powder Synthesized through Concurrent Formation of the Nanosized Particles of Both Starch and Silver  [PDF]
A. Hebeish,M. H. El-Rafie,M. A. El-Sheikh,Mehrez E. El-Naggar
Journal of Nanotechnology , 2013, DOI: 10.1155/2013/201057
Abstract: Green innovative strategy was developed to accomplish silver nanoparticles formation of starch-silver nanoparticles (St-AgNPs) in the powder form. Thus, St-AgNPs were synthesized through concurrent formation of the nanosized particles of both starch and silver. The alkali dissolved starch acts as reducing agent for silver ions and as stabilizing agent for the formed AgNPs. The chemical reduction process occurred in water bath under high-speed homogenizer. After completion of the reaction, the colloidal solution of AgNPs coated with alkali dissolved starch was cooled and precipitated using ethanol. The powder precipitate was collected by centrifugation, then washed, and dried; St-AgNPs powder was characterized using state-of-the-art facilities including UV-vis spectroscopy, Transmission Electron Microscopy (TEM), particle size analyzer (PS), Polydispersity index (PdI), Zeta potential (ZP), XRD, FT-IR, EDX, and TGA. TEM and XRD indicate that the average size of pure AgNPs does not exceed 20?nm with spherical shape and high concentration of AgNPs (30000?ppm). The results obtained from TGA indicates that the higher thermal stability of starch coated AgNPS than that of starch nanoparticles alone. In addition to the data obtained from EDX which reveals the presence of AgNPs and the data obtained from particle size analyzer and zeta potential determination indicate that the good uniformity and the highly stability of St-AgNPs). 1. Introduction A nanoscale metal is defined as a metal that has a structure in the nanometer size range, usually ranging from 1 to 100?nm. Of these metal nanoparticles, silver nanoparticles (AgNPs) have been by far the most important both from scientific and practical points of view by virtue of their potential use in industrial and other applications [1]. Intensive research has been focused on AgNPs due to their unique optical electronic, [2, 3] catalytic, [4–6], and antimicrobial [7–9] properties which are greatly different from bulk substances. Such properties strongly depend on size and shape of AgNPs as well as on their interactions with the stabilizing agent and the surrounding media in addition to the manner of their preparation. Thus, the controllable synthesis of the nanocrystals is a key challenge to achieve their better applied characteristics [10]. AgNPs have been synthesized using various methods. The physicochemical methods (e.g., ultrasound, templates, and milling process [11–13]), as well as “green” synthesis using microorganisms, enzymes, plants, or plant extracts [14–16] are equally effective, but sometimes they
Comparison of properties of silver-metal oxide electrical contact materials  [PDF]
?osovi? V.,Talijan N.,?ivkovi? D.,Mini? D.
Journal of Mining and Metallurgy, Section B : Metallurgy , 2012, DOI: 10.2298/jmmb111101013c
Abstract: Changes in physical properties such as density, porosity, hardness and electrical conductivity of the Ag-SnO2 and Ag-SnO2In2O3 electrical contact materials induced by introduction of metal oxide nanoparticles were investigated. Properties of the obtained silver-metal oxide nanoparticle composites are discussed and presented in comparison to their counterparts with the micro metal oxide particles as well as comparable Ag-SnO2WO3 and Ag-ZnO contact materials. Studied silvermetal oxide composites were produced by powder metallurgy method from very fine pure silver and micro- and nanoparticle metal oxide powders. Very uniform microstructures were obtained for all investigated composites and they exhibited physical properties that are comparable with relevant properties of equivalent commercial silver based electrical contact materials. Both Ag-SnO2 and Ag- SnO2In2O3 composites with metal oxide nanoparticles were found to have lower porosity, higher density and hardness than their respective counterparts which can be attributed to better dispersion hardening i.e. higher degree of dispersion of metal oxide in silver matrix.
The Effect of Hydrothermal Treatment on Silver Nanoparticles Stabilized by Chitosan and Its Possible Application to Produce Mesoporous Silver Powder  [PDF]
Dang Viet Quang,Nguyen Hoai Chau
Journal of Powder Technology , 2013, DOI: 10.1155/2013/281639
Abstract: Aggregation state of silver nanoparticles dispersed in an aqueous solution greatly varies with storage and treatment conditions. In this study, silver nanoparticles synthesized in chitosan solution by a chemical reduction method were hydrothermally treated at different temperatures. The variation in the aggregation state of silver nanoparticles in the solution was observed by UV-Vis spectroscopy and field emission transmission electron microscopy. Results indicated that a phase transition occurred while silver nanoparticles were hydrothermally treated for 5 h at 100 and ; however, they aggregated and completely precipitated at . Mesoporous silver powder obtained by hydrothermal treatment at was characterized by using X-ray diffraction technique, BET analyzer, and scanning electron spectroscope. 1. Introduction Silver nanoparticles have become the most widely commercialized nanomaterials due to thier unique physicochemical and biological properties [1]. Silver nanoparticles can be synthesized and stabilized in the presence of polymers [2–7] in an aqueous solution or organic solvents. They can also be stabilized in the pores of porous materials where tiny spaces or channels act as spatial hindrance, which inhibits the growth of silver particles [8–11]. The size and shape of silver nanoparticles in porous materials depend on their pore diameters and are almost stable after synthesis, whereas that of silver nanoparticles in solutions is affected by various factors including storing conditions, the type and concentration of stabilizer, the concentration of silver nanoparticles, and synthetic routes. The properties, applicability and efficiency of final products are greatly related to the size, the shape, and the aggregation state of silver nanoparticles. Silver powder has been widely used in catalysis, electronics, chemical industry, and biomedical application [12]. Electronic industry consumes large amounts of silver powder that is usually used as conductive paste [13–16]. Several studies have indicated that mesoporous silver powders with higher porosity and larger surface area engender higher application efficiencies such as reducing firing temperature of conductive film [17], enhancing the resistance of heat exchanger material at ultralow temperature [18], or increasing catalytic activity of an oxidation reaction [19, 20]. Recently, due to the rapid development of electronic industry, it demands a huge amount of high quality silver powder. Thus, scientists have investigated and proposed different methods such as spray pyrolysis [21–23], sonochemical
Comparative study of the morphology and properties of PP/LLDPE/wood powder and MAPP/LLDPE/wood powder polymer blend composites
eXPRESS Polymer Letters , 2010, DOI: 10.3144/expresspolymlett.2010.88
Abstract: In this study, polypropylene (PP)/linear low-density polyethylene (LLDPE) and maleic anhydride grafted polypropylene (MAPP)/LLDPE blend systems were comparatively investigated. The blends and composites contained equal amounts of the two polymers, and the compatibility and miscibility between the two polymers were investigated. Composites with 10, 20 and 30 wt% wood powder (WP), but still with equal amounts of the two polymers, were prepared and investigated. The morphologies, as well as mechanical and thermal properties, of the blends and the blend composites were investigated. The MAPP/LLDPE blend and composites showed better properties than the PP/LLDPE blend and composites as a result of the stronger interfacial interaction between MAPP, LLDPE and WP. The SEM and DSC results of the PP/LLDPE/WP blend composites showed that WP located itself more in the LLDPE phase. In the MAPP/LLDPE/WP composites the WP was in contact with both polymers, although it had a greater affinity for MAPP. The TGA results show that the MAPP/LLDPE blend and composites are more thermally stable than the PP/LLDPE blend and composites.
Study on the Professional Identity of Japanese Traditional Craftspeople: Through Interviews with Maki-e Craftspeople  [PDF]
Chieko Narita, Yutaro Shimode, Kazushi Yamada, Noriyuki Kida
Advances in Anthropology (AA) , 2015, DOI: 10.4236/aa.2015.54022
Abstract: This study focused on the formation process of the professional identity of Maki-e craftspeople, which is one of the Japanese traditional crafts. This study aimed to clarify the professional identity of Maki-e craftspeople by comparing skilled craftspeople and young craftspeople. The participants were four Maki-e craftspeople held in different positions, and semi-structured interviews about the professional identity were conducted. As a result, the three unchangeable aspects of the professional identity of Maki-e craftspeople were shown through this research. Furthermore, the two professional identities of Maki-e craftspeople over the course of the social changes were shown. The knowledge gained from this study is important to achieve greater understanding of career formation in highly specialized occupation.
Physicochemical and Atomic Characterization of Silver Powder after Biofield Treatment
Mahendra Kumar Trivedi, Rama Mohan Tallapragada, Alice Branton, Dahryn Trivedi , Gopal Nayak, Omprakash Latiyal and Snehasis Jana
Bioengineering & Biomedical Science , 2015, DOI: 10.4172/2155-9538.1000165
Abstract: Silver is widely utilized as antimicrobial agent and wound dressing, where its shape, size, surface area, and surface charge play an important role. The aim of present study was to evaluate the impact of biofield treatment on physicochemical and atomic properties of silver powder. The silver powder was divided into two groups, coded as control and treatment. The treatment group received Mr. Trivedi’s biofield treatment. Subsequently, control and treated samples were characterized using particle size analyzer, X-ray diffraction (XRD) and surface area analyser. Particle size data exhibited that particle sizes d10, d50, d90, and d99 (Size, below which 10, 50, 90, and 99% particle are present, respectively) of treated silver powder were substantially reduced up to 95.8, 89.9, 83.2, and 79.0% on day 84 as compared to control. XRD results showed that lattice parameter, unit cell volume, and atomic weight were reduced, whereas density and nuclear charge per unit volume were found to be increased as compared to control. In addition, the crystallite size was significantly reduced up to 70% after biofield treatment on day 105 as compared to control. Furthermore, the surface area of treated silver powder was substantially enhanced by 49.41% on day 68 as compared to control. These findings suggest that biofield treatment has significantly altered the atomic and physicochemical properties which could make silver more useful in antimicrobial applications.
Physicochemical and Atomic Characterization of Silver Powder after Biofield Treatment
Mahendra Kumar Trivedi, Rama Mohan Tallapragada, Alice Branton, Dahryn Trivedi, Gopal Nayak, Omprakash Latiyal, Snehasis Jana
Journal of Bioengineering & Biomedical Science , 2015, DOI: 10.4172/2155-9538.1000165
Abstract: Silver is widely utilized as antimicrobial agent and wound dressing, where its shape, size, surface area, and surface charge play an important role. The aim of present study was to evaluate the impact of biofield treatment on physicochemical and atomic properties of silver powder. The silver powder was divided into two groups, coded as control and treatment. The treatment group received Mr. Trivedi’s biofield treatment. Subsequently, control and treated samples were characterized using particle size analyzer, X-ray diffraction (XRD) and surface area analyser. Particle size data exhibited that particle sizes d10, d50, d90, and d99 (Size, below which 10, 50, 90, and 99% particle are present, respectively) of treated silver powder were substantially reduced up to 95.8, 89.9, 83.2, and 79.0% on day 84 as compared to control. XRD results showed that lattice parameter, unit cell volume, and atomic weight were reduced, whereas density and nuclear charge per unit volume were found to be increased as compared to control. In addition, the crystallite size was significantly reduced up to 70% after biofield treatment on day 105 as compared to control. Furthermore, the surface area of treated silver powder was substantially enhanced by 49.41% on day 68 as compared to control. These findings suggest that biofield treatment has significantly altered the atomic and physicochemical properties which could make silver more useful in antimicrobial applications.
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