scholarly journals STUDYING THE INFLUENCE OF THE TEMPERATURE ON MORPHOLOGY OF CONGLOMERATES FROM COPPER NANOPARTICLES OBTAINED BY ELECTROEROSION DISPERSION

2021 ◽  
Vol 1 (67) ◽  
pp. 38-42
Author(s):  
E. Klikin ◽  
N. Kuvardin ◽  
R. Lavrov
Keyword(s):  
Petroleum Ether ◽  
Copper Nanoparticles ◽  
Visual Observation ◽  
Temperature Factor ◽  
Liquid Media ◽  
Starch Solution ◽  
Size And Shape ◽  
Digital Microscope ◽  
Different Temperatures ◽  
Electroerosion Dispersion

Aim. To obtain conglomerates from copper nanoparticles by the method of electroerosive dispersion in various liquid media (in 1% starch solution, ethanol, acetone, kerosene, petroleum ether) at two different temperatures (negative and room). Assessment of the influence of this factor on the size and shape of the resulting conglomerates. Methods. Methods based on visual observation of the obtained particles using a digital microscope at a magnification of 600x. Results. The results are presented in the form of micrographs of the obtained particles. Conclusions. Conclusions are drawn on the study of the influence of the temperature factor on the morphology (size, shape and ordering) of the resulting conglomerates.

scholarly journals Poly(N-isopropylacrylamide-co-methacrylic acid) microgel stabilized copper nanoparticles for catalytic reduction of nitrobenzene

2015 ◽  
Vol 33 (3) ◽  
pp. 627-634 ◽  
Author(s):  
Zahoor H. Farooqi ◽  
Zonarah Butt ◽  
Robina Begum ◽  
Shanza Rhauf Khan ◽  
Ahsan Sharif ◽  
...  
Keyword(s):  
Copper Nanoparticles ◽  
Methacrylic Acid ◽  
Catalytic Reduction ◽  
Aqueous Media ◽  
Activation Parameters ◽  
Reducing Agent ◽  
Different Temperatures ◽  
Entropy Of Activation ◽  
Micro Reactors

Abstract Poly(N-isopropylacrylamide-co-methacrylic acid) microgels [p(NIPAM-co-MAAc)] were synthesized by precipitation polymerization of N-isopropylacrylamide and methacrylic acid in aqueous medium. These microgels were characterized by dynamic light scattering and Fourier transform infrared spectroscopy. These microgels were used as micro-reactors for in situ synthesis of copper nanoparticles using sodium borohydride (NaBH4) as reducing agent. The hybrid microgels were used as catalysts for the reduction of nitrobenzene in aqueous media. The reaction was performed with different concentrations of cat­alyst and reducing agent. A linear relationship was found between apparent rate constant (kapp) and amount of catalyst. When the amount of catalyst was increased from 0.13 to 0.76 mg/mL then kapp was increased from 0.03 to 0.14 min-1. Activation parameters were also determined by performing reaction at two different temperatures. The catalytic process has been discussed in terms of energy of activation, enthalpy of activation and entropy of activation. The synthesized particles were found to be stable even after 14 weeks and showed catalytic activity for the reduction of nitrobenzene.

scholarly journals Green Synthesis and Characterization of Copper Nanoparticles Using Fortunella margarita Leaves

Polymers ◽  
2021 ◽  
Vol 13 (24) ◽  
pp. 4364
Author(s):  
Rutaba Amjad ◽  
Bismillah Mubeen ◽  
Syed Shahbaz Ali ◽  
Syed Sarim Imam ◽  
Sultan Alshehri ◽  
...  
Keyword(s):  
Copper Nanoparticles ◽  
Color Change ◽  
Metal Oxide Nanoparticles ◽  
Visual Observation ◽  
X Ray Diffraction ◽  
Synthesis Of Nanoparticles ◽  
Characteristic Absorption Peak ◽  
Bluish Green ◽  
Dark Green

The use of biomaterials in the synthesis of nanoparticles is one of the most up-to-date focuses in modern nanotechnologies and nanosciences. More and more research on green methods of producing metal oxide nanoparticles (NP) is taking place, with the goal to overcome the possible dangers of toxic chemicals for a safe and innocuous environment. In this study, we synthesized copper nanoparticles (CuNPs) using Fortunella margarita leaves’ extract, which reflects its novelty in the field of nanosciences. The visual observation of a color change from dark green to bluish green clearly shows the instant and spontaneous formation of CuNPs when the phytochemicals of F. margarita come in contact with Cu+2 ions. The synthesis of CuNPs was carried out at different conditions, including pH, temperature, concentration ratio and time, and were characterized with UV-Vis absorption spectra, scanning electron microscope (SEM) and X-ray diffraction (XRD). The UV-Vis analysis reveals the surface plasmon resonance property (SPR) of CuNPs, showing a characteristic absorption peak at 679 nm, while SEM reveals the spherical but agglomerated shape of CuNPs of the size within the range of 51.26–56.66 nm.

DEVELOPMENT OF TECHNOLOGY FOR ELECTROEROSIVE COPPER NANOPARTICLES FROM WASTE

2016 ◽  
Vol 3 (1) ◽  
pp. 520-524
Author(s):  
Маховицкий ◽  
E. Makhovitskiy ◽  
Агеев ◽  
E. Ageev ◽  
Хорьякова ◽  
...  
Keyword(s):  
Experimental Research ◽  
Copper Nanoparticles ◽  
Copper Wire ◽  
Low Energy ◽  
Energy Costs ◽  
Conductive Material ◽  
Technology Of Production ◽  
Electroerosion Dispersion

One of the most promising methods of processing of practically any conductive material, characterized by relatively low energy costs and environmental cleanliness of the process, is the method of electroerosion dispersion. However, to obtain the electro erosion dispersing of nanoparticles it is necessary to conduct a comprehensive theoretical and experimental research. The article describes the technology of production electroerosion copper nanoparticles from the waste electrical copper wire.

scholarly journals The photometric matching field

1923 ◽  
Vol 104 (725) ◽  
pp. 302-315 ◽  
Keyword(s):  
Experimental Work ◽  
Retinal Image ◽  
Visual Observation ◽  
The State ◽  
Size And Shape ◽  
Standard Work ◽  
Minimum Contrast ◽  
Number Of Factors ◽  
The Common ◽  
Matching Field

The basis of experimental photometry is the power of the eye to judge the equality of illumination in the parts of a photometric field. It is commonly stated that the parts to be equalised should be uniformly illuminated and should be as far as possible placed in immediate juxtaposition, so that the line of separation tends to disappear when equality is reached. (We do not consider for the present the case of photometers employing the equal contrast principle.) Until comparatively recently, however, it was not fully realised that the minimum contrast which is perceptible depends on several conditions amongst the chief of which are :— (1) The brightness of the retinal image of the field. (2) The state of adaptation of the eye. (3) The portion of the retina employed for visual observation. (4) The size and shape of the contrasting patches. The “ standard ” work on the value of the so-called Fechner fraction is that of König and Brodhun who employed a bi-partite field and produced the contrast by a polarisation method. The field was in the form of two superimposed rectangles the height of each subtended 3° at the eye, while the common breadth was 4⅓°. Their results have been examined and recalculated by Nutting, who also examined the value of the unit of brightness employed. Blanchard also described experimental work bearing on the same point. Owing to the number of factors concerned, however, the various conditions obtaining in some of the experiments make the results difficult to compare.

Crystallite size and shape in Twaron fibers heat treated at different temperatures using WAXS

2006 ◽  
Vol 100 (6) ◽  
pp. 4910-4916 ◽  
Author(s):  
Anjana Jain ◽  
S. Abhishek ◽  
Sangappa ◽  
S. S. Mahesh ◽  
R. Somashekar
Keyword(s):  
Crystallite Size ◽  
Size And Shape ◽  
Heat Treated ◽  
Different Temperatures

Investigate Jatropha Oil as New Source of Lubricant Oil

2013 ◽  
Vol 465-466 ◽  
pp. 201-205 ◽  
Author(s):  
Iman Golshokouh ◽  
Samion Syahrullail ◽  
Shahab Shariatmadari ◽  
Farid Nasir Ani
Keyword(s):  
Physical Properties ◽  
Ccd Camera ◽  
Mineral Oil ◽  
Jatropha Oil ◽  
Renewable Source ◽  
Hydraulic Oil ◽  
Lubricant Oil ◽  
Digital Microscope ◽  
Different Temperatures ◽  
American Society

This research investigated the physical properties of Jatropha oil to determine its viability as a clean and renewable source of lubricant oil. The study was performed using a four-ball tribotester, CCD camera, digital microscope and viscosity meter. The experiment was conducted using different temperatures (55, 75 and 105°C). The experiment was conducted of constant parameters as speed; load and time under the American Society for Testing and Materials (ASTM), number D 4172.The data included the evaluation of anti-wear, anti-friction and viscosity of Jatropha oil. To evaluate lubricant ability all results of this research were compared to findings regarding hydraulic oil as a mineral oil-based lubricant. The results showed that, under various temperatures Jatropha oil had better lubricant ability compared to hydraulic mineral oil.

Modulations in Self-Organization Properties of Surfactant in Aqueous Ionic Liquid Media

2020 ◽  
Vol 234 (10) ◽  
pp. 1603-1621
Author(s):  
Harsh Kumar ◽  
Arjuna Katal ◽  
Naval Kishor Rawat
Keyword(s):  
Electrostatic Interactions ◽  
Structural Changes ◽  
Anionic Surfactants ◽  
Sodium Dodecyl ◽  
Aggregation Behavior ◽  
Liquid Media ◽  
Fluorescence Studies ◽  
Thermodynamical Parameters ◽  
Different Temperatures ◽  
Ft Ir

AbstractIonic liquids (ILs) give a wide scope of favorable applications due to their much-upgraded properties. The strong electrostatic interactions between the cationic moiety of IL and the anionic surfactant play a very important role in the assembly of the large aggregates. We have investigated the aggregation behavior of anionic surfactants and IL in aqueous solution. Different temperatures and concentrations of IL have been taken to study the effect on critical micelles concentrations of surfactant. The critical micelle concentration values obtained by conductivity measurements are further confirmed by the fluorescence studies. The method is based on the fit of the experimental obtained raw data of fluorescence spectroscopy to a simple nonlinear category of a Boltzmann type sigmoidal function. Thermodynamical parameters of micellization $\Delta H_{m}^{0}$, $\Delta G_{m}^{0}$ and $\Delta S_{m}^{0}$ have been considered to study the effect of aqueous IL 1-butyl-3-methylimidazolium bromide concentration and temperature on aggregation behavior of surfactant sodium dodecyl sulfate. FT-IR spectra have been studies to verify the structural changes arise in the aqueous IL and surfactant system.

scholarly journals MATHEMATICAL JUSTIFICATION OF NATURAL MINERAL SORBENTS MIXTURE EFFICIENCY FOR LOW MINERALIZED DRAINAGE WATER TREATMENT DEPENDING ON TEMPERATURE

2020 ◽  
Author(s):  
V. A. Suprun ◽  
◽  
M. A. Shiryaeva ◽  
Keyword(s):  
Drainage Water ◽  
Temperature Factor ◽  
Analysis Tool ◽  
Scatter Diagram ◽  
Average Temperature ◽  
Different Temperatures ◽  
Statistical Analysis Tool ◽  
Temperature Parameter ◽  
The Relationship ◽  
Model Water

Purpose: to identify the relationship of sorption of a complex sorbent with a temperature factor and its mathematical substantiation. Material and methods. As a material for the study, a complex sorbent obtained from a mixture of perlite and agroionite in a ratio of 27:73 was used. The experiment was carried out in laboratory conditions at different temperatures. At certain intervals, when measuring the total salinity of the solutions, the temperature parameter was also measured. During the study, the air temperature was measured. For the experiment, a model water of three salinity levels: 3.1; 5; 7 g/l was used. The weighed portions of a mixture of sorbents weighing 27.5 g with model solutions, 300 ml each, were placed in a reservoir. Measurements were carried out after 5; 10; 20; 30 min; 1; 2; 24; 48 h using a HI 8733 conductometer from Hanna. Results. As a result of the study, the dynamics of the salinity of the model water under the action of a complex sorbent was obtained, a scatter diagram was constructed. It is a statistical analysis tool, with the help of which the dependence and the nature of the relationship between the two process parameters are revealed. According to the results obtained, it can be concluded that there is a positive relationship in the experiments performed. The efficiency of the process depends on temperature readings with a slight deviation. Thus, at an average temperature of 26.3 °C, the total mineralization index is lower than at an average temperature of 19.8 °C. Conclusions. By constructing a scatter diagram and a matrix scatter diagram, a nonlinear relationship between sorption by a complex sorbent and the temperature factor was revealed.

A Comparison of the Size and Shape of Radiofrequency Lesions Produced by Different Temperatures Using Straight and Curved Electrodes

2000 ◽  
Vol 39 (2) ◽  
pp. 260 ◽  
Author(s):  
Kee Heon Lee ◽  
Seon Hye Yun ◽  
Hyun Ju Kim ◽  
Bae Hee Jung ◽  
So Young Lim ◽  
...  
Keyword(s):  
Size And Shape ◽  
Different Temperatures ◽  
Radiofrequency Lesions
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