scholarly journals Growth of SiO2 microparticles by using modified Stὂber method: Effect of ammonia solution concentration and TEOS concentration

2020 ◽  
Author(s):  
Shrestha Bhattacharya ◽  
Aishik Basu Mallick ◽  
Mrinal Dutta ◽  
Sanjay K. Srivastava ◽  
P. Prathap ◽  
...  
Keyword(s):  
Solution Concentration ◽  
Ammonia Solution ◽  
Method Effect ◽  
Teos Concentration

scholarly journals Gd/Sm-Pr Co-Doped Ceria: A First Report of the Precipitation Method Effect on Flash Sintering

Materials ◽  
2019 ◽  
Vol 12 (8) ◽  
pp. 1218 ◽  
Author(s):  
Luca Spiridigliozzi ◽  
Lorenzo Pinter ◽  
Mattia Biesuz ◽  
Gianfranco Dell’Agli ◽  
Grazia Accardo ◽  
...  
Keyword(s):  
Ammonia Solution ◽  
Current Control ◽  
Precipitation Method ◽  
Precipitation Process ◽  
Sintering Behavior ◽  
Method Effect ◽  
Flash Sintering ◽  
Co Precipitation ◽  
First Time ◽  
Flash Event

In this work, ceria-based ceramics with the composition Gd0.14Pr0.06Ce0.8O2-δ and Sm0.14Pr0.06Ce0.8O2-δ, were synthesized by a simple co-precipitation process using either ammonium carbonate or ammonia solution as a precipitating agent. After the calcination, all of the produced samples were constituted by fluorite-structured ceria only, thus showing that both dopant and co-dopant cations were dissolved in the fluorite lattice. The ceria-based nanopowders were uniaxially compacted and consequently flash-sintered using different electrical cycles (including current-ramps). Different results were obtained as a function of both the adopted precipitating agent and the applied electrical cycle. In particular, highly densified products were obtained using current-ramps instead of “traditional” flash treatments (with the power source switching from voltage to current control at the flash event). Moreover, the powders that were synthesized using ammonia solution exhibited a low tendency to hotspot formation, whereas the materials obtained using carbonates as the precipitating agent were highly inhomogeneous. This points out for the first time the unexpected relevance of the precipitating agent (and of the powder shape/degree of agglomeration) for the flash sintering behavior.

The effect of ammonia solution concentration on the synthesis process of MgFe2O4 based on natural iron sand as adsorbent of Pb ions

2020 ◽  
Author(s):  
Eko A. Setiadi ◽  
Nining S. Asri ◽  
Yara A. Wijayanti ◽  
Anggito P. Tetuko ◽  
Perdamean Sebayang
Keyword(s):  
Solution Concentration ◽  
Ammonia Solution ◽  
Synthesis Process ◽  
Natural Iron ◽  
Pb Ions

Synthesis of SnO2 Nanoparticles with Varying Particle Sizes and Morphologies by Hydrothermal Method

2011 ◽  
Vol 415-417 ◽  
pp. 585-589
Author(s):  
Dong Xin Wang ◽  
Xu Jin Bao ◽  
Jing Ming Zhong ◽  
Ben Shuang Sun
Keyword(s):  
Hydrothermal Method ◽  
Tin Oxide ◽  
Heating Temperature ◽  
Great Influence ◽  
Solution Concentration ◽  
Ammonia Solution ◽  
Particle Sizes ◽  
Tin Chloride ◽  
Tin Oxide Nanoparticles ◽  
Xrd Patterns

Using ammonia solution and tin chloride as the precursors: tin oxide nanoparticles with different particle sizes and morphologies were synthesised by varying the concentration, heating temperature and ripening time via hydrothermal method. The particles synthesised were characterised by X-ray diffraction (XRD) and transmission electron microscopy (TEM). The TEM micrographs show that rod-like nanoparticles were synthesised when the SnCl4 solution concentration was less than 1.0 mol/L, which was changed to oval shape when the concentration increased above 2.0 mol/L. Polygonal shaped nanoparticles were observed at 220 °C for 48 hours. It was also found that changing temperature had little effect on the morphology but great influence on the size of the particles, which increased from 10 nm to 120 nm from 160 °C to 220 °C and 12 nm to 55 nm from 6 h to 48 h at 200 °C, respectively. XRD patterns indicated that all of nanoparticles synthesised were tin oxide.

scholarly journals Application of AgNPs/rGO Modified Nylon Fabric in Strain Sensing

2021 ◽  
Vol 2109 (1) ◽  
pp. 012017
Author(s):  
Yongqiang Yang ◽  
Yongsong Tan ◽  
Qun Wang ◽  
Yihu Shu ◽  
Qinsheng Wang ◽  
...  
Keyword(s):  
Silver Nanoparticles ◽  
Graphene Oxide ◽  
Screen Printing ◽  
Strain Sensor ◽  
Solution Concentration ◽  
Ammonia Solution ◽  
Strain Sensing ◽  
Nylon Fabric ◽  
Reduced Graphene ◽  
Different Strains

Abstract The graphene oxide slurry was printed on the pre-stretched and non-pre-stretched nylon fabric by screen printing, and immersed in silver ammonia solution of different concentrations, and then reduced to obtain silver nanoparticles/reduced graphene oxide (AgNPs/rGO) modified nylon fabric with excellent conductivity. The surface morphology of the fabric was observed, and the performances of the fabric sensor that was scraped with graphene oxide slurry between the pre-stretched and non-pre-stretched states were explored. The resistance responses of the nylon fabric finished with different concentrations of silver ammonia solution under different strains (1%, 2%, 3%, 4%, 5%, 10%, 15%, 20%) were investigated. The results showed that the nylon strain sensor was more sensitive and stable when the graphene oxide slurry was scraped in the pre-stretched state, and while the silver ammonia solution concentration was 10 mg/mL, the nylon fabric had maximum sensitivity and lowest hysteresis performance.

Surface Modification of Carbon Electrodes for Supercapacitor Using Ammonia Water

2011 ◽  
Vol 396-398 ◽  
pp. 1265-1268 ◽  
Author(s):  
Ren Qing Wang ◽  
Mei Gen Deng
Keyword(s):  
Surface Modification ◽  
Activated Carbon ◽  
Specific Capacitance ◽  
Carbon Materials ◽  
Solution Concentration ◽  
Ammonia Solution ◽  
Constant Current ◽  
Power Performance ◽  
Ammonia Water ◽  
Constant Current Charge

In this work, activated carbon was modified by ammonia water. Cyclic voltammetry and constant current charge-discharge were used to characterize the electrochemical performance of the samples in 1.0 mol/L Et4NBF4-PC solution. As a result, optimal conditions for surface modification of activated carbon have been examined as an ammonia solution concentration of 5wt.%. Specific capacitance can be improved significantly by surface modification of carbon materials. The specific capacitance of the carbon modified with 5.0wt.% ammonia water reached 114 F/g at a current density of 3.0 mA/cm2, which is 14% higher than that of untreated sample. In addition, the modified carbon materials possess excellent power performance.

Influence of Precursor Solution Concentration on Zinc Oxide Nanostructures by Hydrothermal Growth

2014 ◽  
Vol 875-877 ◽  
pp. 562-566
Author(s):  
Zong Bo Huang ◽  
X.P. Zou ◽  
G.Q. Yang ◽  
X.M. Lv ◽  
C.L. Wei ◽  
...  
Keyword(s):  
Tin Oxide ◽  
Indium Tin Oxide ◽  
Precursor Solution ◽  
Solution Concentration ◽  
Ammonia Solution ◽  
Zinc Nitrate ◽  
Hydrothermal Growth ◽  
Zinc Oxide Nanostructures ◽  
Oxide Nanostructures ◽  
Precursor Solution Concentration

In this paper, various ZnO nanostructures, such as rods, flowers were grown on indium-tin-oxide (ITO) substrates by hydrothermal growth at low temperature, using the different concentrations of equimolar (1:1) zinc nitrate (Zn (NO3)26H2O) and methenamine (C6H12N4) mixed as precursors solution, and adding ammonia solution to control the pH levels. SEM, XRD were utilized to characterize morphologies and crystal structures of ZnO. It was indicated that the concentration of precursor solution leads to the significantly changes in the nanostructured ZnO. The possible growth mechanism is discussed in this work.

Sonocatalyzed Ammonothermal Preparation of Fine Lithium Niobate Powders

2008 ◽  
Vol 55-57 ◽  
pp. 37-40
Author(s):  
A. Rujiwatra ◽  
N. Thammajak ◽  
Y. Chimupala ◽  
Pitak Laoratanakul
Keyword(s):  
Lithium Niobate ◽  
Single Phase ◽  
Fine Powder ◽  
Critical Factor ◽  
Solution Concentration ◽  
Ammonia Solution ◽  
Lithium Nitrate ◽  
Ultrasonic Activation ◽  
Fine Powders ◽  
Single Phase Formation

The so-called sonocatalyzed ammonothermal technique has been developed for the preparation of lithium niobate fine powders from commercially as-received niobium pentoxide and lithium nitrate. The present work shows that the application of ultrasonic activation prior to the ammonothermal treatment can produce a single phase lithium niobate fine powder at a relatively low temperature of 220°C. The influences of Li-precursors, ammonia solution concentration, reaction temperature and time, as well as Li:Nb mole ratio - which is evidentially the most critical factor promoting a single phase formation - are discussed.

Calcium Carbonate Production through Direct Mineral Carbon Dioxide Sequestration

2014 ◽  
Vol 699 ◽  
pp. 1020-1025 ◽  
Author(s):  
Amin Azdarpour ◽  
Radzuan Junin ◽  
Mohammad Asadullah ◽  
Hossein Hamidi ◽  
Muhammad Manan ◽  
...  
Keyword(s):  
Carbon Dioxide ◽  
Particle Size ◽  
Calcium Carbonate ◽  
Reaction Temperature ◽  
Carbon Dioxide Sequestration ◽  
Solution Concentration ◽  
Ammonia Solution ◽  
Carbonate Production ◽  
Calcium Carbonates ◽  
Fgd Gypsum

Mineral carbon dioxide sequestration provides a leakage free and permanent method of CO2 disposal to produce environmentally benign and stable solid carbonates. FGD gypsum as a source of calcium was proposed as the potential feedstock in this study. The purpose of this laboratory study was to investigate the effects of reaction parameters such as CO2 pressure, reaction temperature, particle size, and ammonia solution concentration on calcium carbonate purity through Merseburg process. Increasing the reaction temperature as well as the pressure was very effective in improving the calcium carbonate purity. High purity calcium carbonate was produced when reaction temperature and CO2 was increased to 400 °C and 70 bar, resulting in 93% and 94% purity, respectively. Experimental results showed that reducing particle size was also effective in enhancing the calcium carbonate purity in which the smallest particles produced higher purity calcium carbonates rather than larger particles. The role of ammonia solution on calcium carbonate purity was found to be beneficial in improving the calcium carbonate purity in which increasing the ammonia solution increased calcium carbonate purity significantly in all experiments.

The Precipitation of Si in AlCuSi Thin Films

1973 ◽  
Vol 31 ◽  
pp. 34-35 ◽  
Author(s):  
R. M. Anderson
Keyword(s):  
Electron Microscopy ◽  
Thin Films ◽  
Heat Treatment ◽  
Solid Solution ◽  
Integrated Circuit ◽  
Copper Film ◽  
Solution Concentration ◽  
X Ray ◽  
Silicon Thin Films ◽  
Before And After

Aluminum-copper-silicon thin films have been considered as an interconnection metallurgy for integrated circuit applications. Various schemes have been proposed to incorporate small percent-ages of silicon into films that typically contain two to five percent copper. We undertook a study of the total effect of silicon on the aluminum copper film as revealed by transmission electron microscopy, scanning electron microscopy, x-ray diffraction and ion microprobe techniques as a function of the various deposition methods.X-ray investigations noted a change in solid solution concentration as a function of Si content before and after heat-treatment. The amount of solid solution in the Al increased with heat-treatment for films with ≥2% silicon and decreased for films <2% silicon.

Sign in / Sign up

Export Citation Format

Share Document