Synthesis of Several Micrometer-Size Cu Particles by a Green Wet Reduction Method

2014 ◽  
Vol 711 ◽  
pp. 210-213
Author(s):  
Jun Ho Hwang ◽  
Jong Hyun Lee
Keyword(s):  
Particle Size ◽  
Chemical Process ◽  
Reduction Method ◽  
Average Particle Size ◽  
Reducing Agent ◽  
Average Particle ◽  
Effective Agent ◽  
Powder Samples ◽  
Wet Chemical ◽  
Micrometer Size

Several micrmeter-size Cu powders were synthesized by a simple and green wet-chemical process. Moreover, changes in particle size are examined with different synthesis temperatures and amounts of gelatin reducing agent. All powder samples synthesized in this study were indexed as a Cu phase despite the synthesis was performed in air. The particle size decreased with increasing the gelatin content in principle, indicating that gelatin is an effective agent in suppressing aggregation between synthesized particles. The smallest average particle size was 1.53 μm.

scholarly journals Effects Of Process Parameters On Cu Powder Synthesis Yield And Particle Size In A Wet-Chemical Process

2015 ◽  
Vol 60 (2) ◽  
pp. 1247-1250 ◽  
Author(s):  
Y.M. Shin ◽  
J.-H. Lee
Keyword(s):  
Particle Size ◽  
Ascorbic Acid ◽  
Chemical Process ◽  
Average Particle Size ◽  
Average Particle ◽  
Distilled Water ◽  
Water Mixture ◽  
Powder Synthesis ◽  
Wet Chemical ◽  
Synthesis Yield

Abstract This study presents a simple wet-chemical process to prepare several micron-size Cu powders. Moreover, changes in powder synthesis yield and particle size are examined with different solvents, synthesis temperatures, and amounts of reducing agent during the synthesis. As a reducing agent and capping agent, L-ascorbic acid and polyvinyl pyrrolidone were used, respectively. The yields in distilled water or an ethylene glycol (EG)/distilled water mixture were higher than that in EG alone, and the yield increased with increasing temperature owing to a lower Δ Gred value. Increasing the L-ascorbic acid concentration also increased the yield. The Cu powder synthesized in 3 h at 90°C in distilled water with 272.8 mM of L-ascorbic acid showed the lowest average particle size of 2.52 μm, indicating mechanisms of short burst nucleation and reduced growth via the increased reduction rate of Cu ions. It is estimated that the nucleation step was nearly completed within 10 min in this system. The Cu powders synthesized in an ethylene glycol/distilled water mixture presented an average particle size of 3.76 μm and the highest yield of 87.9%.

scholarly journals Biosynthesis and Characterization of ZnO Nanoparticles with Extract of Green Seaweed Caulerpa sp.

2017 ◽  
Vol 19 (1) ◽  
pp. 17
Author(s):  
Rodiah Nurbaya Sari ◽  
Nanda Saridewi ◽  
Shofwatunnisa Shofwatunnisa
Keyword(s):  
Particle Size ◽  
Zno Nanoparticles ◽  
Functional Group ◽  
Reduction Method ◽  
Average Particle Size ◽  
Group Analysis ◽  
Average Particle ◽  
Green Seaweed ◽  
Functional Group Analysis

Biosynthesis and characterization of ZnO Nanoparticles by the reduction method have been performed. This study aims to determine the ability of Caulerpa sp. as a reducing agent and stabilizer. Extract Caulerpa sp. was reacted with Zn(CH3COO)2.2H2O solution in variation concentration of 0.05, 0.1, and 0.15 M and the pH of the solution was conditioned with NaOH 0.1 M added became 7, 8, 9. Characterization of ZnO nanoparticles was performed for functional group analysis (FTIR), surface morphology and particle distribution (SEM), knowing the phase type (XRD), and particle size and particle size (PSA). The result of phase analysis by XRD shows that the synthesis of ZnO nanoparticles using green seaweed extract Caulerpa sp. has been successfully performed with the formation of the optimum ZnO nanoparticles 0.15 M at pH 8. The ZnO nanoparticles had a relatively similar particle size distribution with an average particle size of 370.72 nm. Based on FTIR results it was known that the compound suspected to act as a bioreductor and stabilizer agent in the synthesis of ZnO nanoparticles was a protein

THE MANUFACTURING OF NIOBIUM POWDER BY HUNTER PROCESS

2010 ◽  
Vol 17 (02) ◽  
pp. 223-228
Author(s):  
JAE-SIK YOON
Keyword(s):  
Particle Size ◽  
Reaction Temperature ◽  
Average Particle Size ◽  
Reduction Process ◽  
Reducing Agent ◽  
Raw Material ◽  
Average Particle ◽  
Metallothermic Reduction ◽  
Niobium Powder ◽  
Yield Rate

Niobium powder was fabricated by metallothermic reduction process using K2NbF7 as the raw material, KCl and KF as the diluents and Na as the reducing agent. The apparatus for the experiment was designed and built specifically for the present study. Varying properties of niobium powder depending on reaction temperature and excess of reducing agent were analyzed. The niobium particle size increased significantly as the reduction temperature increased from 993 to 1093 K. The particle size was fairly uniform at a given reaction temperature, varying from 0.2 μ m to 50 nm depending on the reaction temperature. The yield of niobium powder increased from 58 to 83% with an increase in reaction temperature. The average particle size of niobium powder was improved from 70 nm to 0.2 μ m with the increase in the amount of Na excess. In addition, the yield rate of Nb powder was 82% in the 5% excess sodium.

scholarly journals Effect of ZrB2 Particle Size on Pressureless Sintering of ZrB2 - ß-Sic Composites

2019 ◽  
Author(s):  
Rosa Maria da Rocha ◽  
Frank Ferrer Sene ◽  
Mariah de Oliveira Juliani ◽  
Caroline Oliveira Davi
Keyword(s):  
Particle Size ◽  
Flexural Strength ◽  
Average Particle Size ◽  
Theoretical Density ◽  
Average Particle ◽  
Pressureless Sintering ◽  
High Melting Temperature ◽  
Powder Samples ◽  
Effect Of Particle Size ◽  
Sic Composites

Zirconium diboride is an ultra high temperature ceramic material that leads this emerging class of materials because of its distinct combination of properties, including high melting temperature (> 3000 °C) and the lowest theoretical density (6.09 g·cm-3) among the borides. This combination of properties makes ZrB2 candidate for airframe leading edges on sharp-bodied reentry vehicles. In this work, the effect of particle size of ZrB2 on the pressureless sintering of ZrB2-SiC composites was studied, using ZrB2 powder with average particle size of 2.6 and 14.2µm. Four different vol% concentration of ß-SiC (0, 10, 20 and 30 vol%) were added to as-received and planetary milled ZrB2 powder. Samples were pressureless sintered at 2050 °C/1h in argon atmosphere. The reduction of initial ZrB2 particle size led to composites with better results of densification, mechanical properties and oxidation resistance regardless ß-SiC addition, showing relative densities around 92.5 %Theoretical Density (Td) and flexural strength and microhardness around 260 MPa and 17.5 GPa, respectively. Composites processed with as-received ZrB2 powder showed increasing in densification and flexural strength with the SiC content increasing. Relative density varied from 74.7 to 90.8 %TD and flexural strength from 102 to 241 MPa, for 0 and 30 vol% of SiC, respectively.

Controlled Preparation and Characterization of Titanium Series Functional Pigment and its Application in Coatings

2017 ◽  
Vol 726 ◽  
pp. 308-315
Author(s):  
Yu Deng ◽  
Jian Xun Zheng ◽  
Qiang Qiang Wang ◽  
Wei Bo Yang ◽  
Song Song Zhang
Keyword(s):  
Particle Size ◽  
Size Distribution ◽  
Average Particle Size ◽  
Average Particle ◽  
Test Results ◽  
Data Logging ◽  
Powder Samples ◽  
Lower Temperature ◽  
Controlled Preparation

In our recent work, we synthesize several spherical rutile TiO2 powders with different average particle size though hydrothermal method using TiCl4 under lower temperature in a shorter reaction period. Afterwards, solar heat-reflection coatings were prepared by using the TiO2 as pigment. The TiO2 powders were characterized by XRD to determine the phase of crystal. The morphology and particle size were observed by using SEM, and the spectral reflectance of the powder samples and coatings were measured using UV/VIS/NIR spectrophotometer. In order to measure the temperature on the back of coatings, the self-assembled equipment which consisted of solar lamps and surface temperature sensors connected to a data logging system was invented. The test results showed that the shape, average particle size and size distribution were closed-packed state and a bigger mean particle size had higher reflectance intensity. Meanwhile, the reflectance was closely connected to the particle size distribution. Actually, the coatings dispersed TiO2 powder with desired size distribution had excellent performance.

scholarly journals Influence of Mn2+ Concentration and UV Irradiation Time on the Luminescence Properties of Mn-doped ZnS Nanocrystals

2009 ◽  
Vol 19 (1) ◽  
pp. 33-38
Author(s):  
Tran Minh Thi
Keyword(s):  
Particle Size ◽  
Uv Irradiation ◽  
Single Phase ◽  
Irradiation Time ◽  
Average Particle Size ◽  
Average Particle ◽  
X Ray Diffraction ◽  
Wet Chemical Method ◽  
Wet Chemical ◽  
Mn Doped

ZnS:Mn were prepared by wet chemical method with Mn doping concentration from 0 at% to 12 at%. The structure and particle size of the obtained powders were measured by X-ray diffraction (XRD) and scanning electron microscopy (SEM) and shown that all samples are single phase with sphalerite crystal structure and average particle size of about 5 - 7 nm. The dependence of Mn2+ ions doped concentration, and UV irradiation time on the luminescent intensity of ZnS:Mn nanocrystals was discussed.

Size-Controlled Synthesis of Magnetite Nanoparticles from Iron Acetate by Thermal Decomposition

2012 ◽  
Vol 217-219 ◽  
pp. 256-259 ◽  
Author(s):  
Hui Ping Shao ◽  
Yi Ming Tan ◽  
Tao Lin ◽  
Zhi Meng Guo
Keyword(s):  
Thermal Decomposition ◽  
Particle Size ◽  
Magnetite Nanoparticles ◽  
Average Particle Size ◽  
Reducing Agent ◽  
Average Particle ◽  
Controlled Synthesis ◽  
Average Size ◽  
Size Controlled

Magnetite nanoparticles with an average particle size ranging from 4.2 to 34.2 nm were synthesized by thermal decomposition of iron(II) acetate with and without a reducing agent. While in the presence of reducing agent, magnetite nanopartices with an average size of 4.2 nm and 12.6 nm were synthesized by varying the amounts of the surfactants. While in the absence of the reducing agent, magnetite nanoparticles with an average size of 26.4 nm and 34.2 nm were prepared.

scholarly journals Pengaruh Variasi Konsentrasi HCl Pada Pembentukan Nanosilika Berbasis Batu Apung

2019 ◽  
Vol 7 (2) ◽  
pp. 161-168
Author(s):  
Lusi Vusfita Sari ◽  
◽  
Posman Manurung ◽  
Yanti Yulianti ◽  
◽  
...  
Keyword(s):  
Particle Size ◽  
Chemical Composition ◽  
Amorphous Phase ◽  
Average Particle Size ◽  
Powder Sample ◽  
Average Particle ◽  
A Value ◽  
Powder Samples ◽  
Solgel Method ◽  
Hcl Concentration

The aims of this research is to determine the effect of variation concentration of HCl on chemical composition, phase formed, and particle size on pumice powder. Nanosilica is made using the solgel method with NaOH concentration 4 M, H2SO4 5 M and variation concentration of HCl 0,5; 0,75; 1; 1,25 dan 1,5 M. The XRF results showed the greatest chemical composition value in the silica pumice powder sample with a value of 77.80%. This value is higher after synthesis at the highest chemical composition value in the nanosilica sample 1,25 M HCl concentration of 87.05%. The XRD results show a diffractogram of pumice powder samples formed by anorthite and albite phases while in the nanosilica sample 1,25 M HCl concentrates are debated with the amorphous phase. The TEM results show particle size of nanosilic sample 1,25 M HCl concentration is 5 nm with average particle size (12.02 ± 3.23) nm.

Determination of grinding parameters of fenugreek seed

1970 ◽  
Vol 26 (1) ◽  
pp. 16 ◽  
Author(s):  
S Balasubramanian ◽  
Rajkumar Rajkumar ◽  
K K Singh
Keyword(s):  
Particle Size ◽  
Energy Consumption ◽  
Moisture Content ◽  
Specific Energy ◽  
Feed Rate ◽  
Average Particle Size ◽  
Specific Energy Consumption ◽  
Average Particle ◽  
Fenugreek Seeds ◽  
Fenugreek Seed

Experiment to identify ambient grinding conditions and energy consumed was conducted for fenugreek. Fenugreek seeds at three moisture content (5.1%, 11.5% and 17.3%, d.b.) were ground using a micro pulverizer hammer mill with different grinding screen openings (0.5, 1.0 and 1.5 mm) and feed rate (8, 16 and 24 kg h-1) at 3000 rpm. Physical properties of fenugreek seeds were also determined. Specific energy consumptions were found to decrease from 204.67 to 23.09 kJ kg-1 for increasing levels of feed rate and grinder screen openings. On the other hand specific energy consumption increased with increasing moisture content. The highest specific energy consumption was recorded for 17.3% moisture content and 8 kg h-1 feed rate with 0.5 mm screen opening. Average particle size decreased from 1.06 to 0.39 mm with increase of moisture content and grinder screen opening. It has been observed that the average particle size was minimum at 0.5 mm screen opening and 8 kg h-1 feed rate at lower moisture content. Bond’s work index and Kick’s constant were found to increase from 8.97 to 950.92 kWh kg-1 and 0.932 to 78.851 kWh kg-1 with the increase of moisture content, feed rate and grinder screen opening, respectively. Size reduction ratio and grinding effectiveness of fenugreek seed were found to decrease from 4.11 to 1.61 and 0.0118 to 0.0018 with the increase of moisture content, feed rate and grinder screen opening, respectively. The loose and compact bulk densities varied from 219.2 to 719.4 kg m-3 and 137.3 to 736.2 kg m-3, respectively.  

Formulating SLN and NLC as Innovative Drug Delivery Systems for Non-Invasive Routes of Drug Administration

2020 ◽  
Vol 27 (22) ◽  
pp. 3623-3656 ◽  
Author(s):  
Bruno Fonseca-Santos ◽  
Patrícia Bento Silva ◽  
Roberta Balansin Rigon ◽  
Mariana Rillo Sato ◽  
Marlus Chorilli
Keyword(s):  
Drug Delivery ◽  
Particle Size ◽  
Drug Release ◽  
Drug Loading ◽  
Average Particle Size ◽  
Delivery Systems ◽  
Average Particle ◽  
Minor Importance ◽  
Routes Of Administration ◽  
Non Invasive

Colloidal carriers diverge depending on their composition, ability to incorporate drugs and applicability, but the common feature is the small average particle size. Among the carriers with the potential nanostructured drug delivery application there are SLN and NLC. These nanostructured systems consist of complex lipids and highly purified mixtures of glycerides having varying particle size. Also, these systems have shown physical stability, protection capacity of unstable drugs, release control ability, excellent tolerability, possibility of vectorization, and no reported production problems related to large-scale. Several production procedures can be applied to achieve high association efficiency between the bioactive and the carrier, depending on the physicochemical properties of both, as well as on the production procedure applied. The whole set of unique advantages such as enhanced drug loading capacity, prevention of drug expulsion, leads to more flexibility for modulation of drug release and makes Lipid-based nanocarriers (LNCs) versatile delivery system for various routes of administration. The route of administration has a significant impact on the therapeutic outcome of a drug. Thus, the non-invasive routes, which were of minor importance as parts of drug delivery in the past, have assumed added importance drugs, proteins, peptides and biopharmaceuticals drug delivery and these include nasal, buccal, vaginal and transdermal routes. The objective of this paper is to present the state of the art concerning the application of the lipid nanocarriers designated for non-invasive routes of administration. In this manner, this review presents an innovative technological platform to develop nanostructured delivery systems with great versatility of application in non-invasive routes of administration and targeting drug release.

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