World Journal of Nano Science and Engineering

Journal Information
ISSN / EISSN : 2161-4954 / 2161-4962
Published by: Scientific Research Publishing, Inc. (10.4236)
Total articles ≅ 139
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Rajapakshe Babilage Sanjitha Dilan Rajapakshe, Gonapala Deniyage Madhusha Chathurangi Gonapaladeniya, Charith Anuruddha Thennakoon, Prabath Nilan Gunasekara, Nirosh Siriwardene, Sudath Annasiwatte, Sayuri Sammanani Niyangoda, Rajapakse Mudiyanselage Gamini Rajapakse
World Journal of Nano Science and Engineering, Volume 12, pp 1-11; https://doi.org/10.4236/wjnse.2022.121001

Abstract:
Galvanization is the process of applying a protective zinc coating to iron or steel to prevent rusting. In the batch hot-dip galvanizing process, large amounts of wastes originate in liquid, solid and gaseous forms. Acidic waste containing iron and zinc ions is produced due to the cleaning of steel prior to zinc coating, which is considered the galvanizing acid waste. The galvanizing effluent used was collected from LTL Galvanizers Pvt. Ltd., Sapugaskanda, Sri Lanka, and converted into antimicrobial hematite (α-Fe2O3) nanoparticles. These nanoparticles were synthesized using a chemical precipitation method. X-Ray Diffraction (XRD) and Scanning Electron Microscopy (SEM) were used to characterize the nanomaterials produced. Two pathogenic bacteria and one pathogenic fungus were used to analyze the antimicrobial activity of the nanomaterials. All the samples showed excellent antibacterial and antifungal properties. And the material can inhibit the growth of both Gram-positive and Gram-negative bacteria. According to the SEM images, some of the hematite particles were around 100 nm in size or less, which confirms that the describing method is viable in synthesizing hematite nanostructures. As shown in the XRD, the major diffraction peak, located at 2θ of 35.617° (110) in addition to minor peaks at 24.87° (012), 33.07° (104), 42.08° (113), 51.18° (024), 53.52° (116) and, 57.46° (018) confirm the spinel structure of iron oxide (α-Fe2O3). The estimated average crystallite size of the nanomaterial is calculated to be 36.74 nm. The durability of the manufactured nanomaterial is excellent. This method is a time-efficient, environmentally friendly, cost-effective and industrially viable way to manufacture antimicrobial hematite (α-Fe2O3) nanomaterials from a galvanizing effluent.
Olfat El Sayed, Inas Battisha, Abdelilah Lahmar, Mimon El Marassi
World Journal of Nano Science and Engineering, Volume 11, pp 25-43; https://doi.org/10.4236/wjnse.2021.112002

Abstract:
Barium titanate tin oxides BaTi0.9Sn0.1O3 referred to as (BTSO) doped with 0.5Er3+ and co-doped with (0.75 and 1) Yb3+ ions, were prepared using a modified sol-gel method and calcinated at 1050˚C in the air for 4 h. The influence of the selected rare earth element on the structure morphology, dielectric properties behavior was investigated. From TEM micrographs, it has appeared that the particles have a spherical shape with a small size in nanoscale. The average particle size is determined both by TEM and XRD diffraction was found to be in agreement and within the range between 45.9 and 57.7 nm. The effects of Lanthanide incorporation on the evolution of these nano-crystalline structures were followed by XRD and (FTIR). The XRD patterns give rise to a single perovskite phase, while the tetragonality was found to decrease gradually with Er3+ and Er3+/Yb3+ ions, respectively. FTIR results showed enhancement of the crystallinity and the absence of carbonates upon increasing Yb3+ ions concentration from 0.75 up to 1 mol%. The dielectric and conductivity properties were found to be enhanced by the nature and the concentration of the lanthanide element (Er3+, Yb3+) in the BTSO host lattice. The Curie temperature (Tc) shifted to a lower value from 117 for BTSO: 0.5Er to 93 for BTSO: 0.5Er/1Yb and the permittivity ε’ increased from 3972 to 6071, so BTSO: 0.5Er/1Yb good crystalline material candidate for capacitors application due to its higher permittivity.
Élcio Nogueira
World Journal of Nano Science and Engineering, Volume 11, pp 1-24; https://doi.org/10.4236/wjnse.2021.111001

Abstract:
The work’s objective is to analyze the influence of the saturation temperature of the R134a refrigerant on the thermal performance of a shell and tube type condenser, with water and aluminum oxide (Al2O3) nanoparticles flowing into the tube. For analysis, the heat exchanger is subdivided into three regions: subcooled liquid, saturated steam, and superheated steam. The shell and tube heat exchanger assumed as the basis for the study has 36 tubes, with rows of 4 tubes in line and three passes into the tube in each region. The parameters used to analyze the performance are efficiency and effectiveness, through variations of quantities such as saturation temperature, the nanofluid’s mass flow rate, fraction in the nanoparticles’ volume, and the number of passes in the tube in each region of the heat exchanger. The obtained results demonstrate that the efficiency is relatively high in all the analyzed situations. In each saturation temperature, the effectiveness can be increased by introducing fractions of nanoparticles in the water or increasing the number of passes in the tube.
Ken-Ichi Saitoh, Naoya Hanashiro
World Journal of Nano Science and Engineering, Volume 11, pp 45-68; https://doi.org/10.4236/wjnse.2021.113003

Abstract:
We formulate a macroscopic particle modeling analysis of metallic materials (aluminum and copper, etc.) based on theoretical energy and atomic geometries derivable from their interatomic potential. In fact, particles in this framework are presenting a large mass composed of huge collection of atoms and are interacting with each other. We can start from cohesive energy of metallic atoms and basic crystalline unit (e.g. face-centered cubic). Then, we can reach to interparticle (macroscopic) potential function which is presented by the analytical equation with terms of exponent of inter-particle distance, like a Lennard-Jones potential usually used in molecular dynamics simulation. Equation of motion for these macroscopic particles has dissipative term and fluctuation term, as well as the conservative term above, in order to express finite temperature condition. First, we determine the parameters needed in macroscopic potential function and check the reproduction of mechanical behavior in elastic regime. By using the present framework, we are able to carry out uniaxial loading simulation of aluminum rod. The method can also reproduce Young’s modulus and Poisson’s ratio as elastic behavior, though the result shows the dependency on division number of particles. Then, we proceed to try to include plasticity in this multi-scale framework. As a result, a realistic curve of stress-strain relation can be obtained for tensile and compressive loading and this new and simple framework of materials modeling has been confirmed to have certain effectiveness to be used in materials simulations. We also assess the effect of the order of loadings in opposite directions including yield and plastic states and find that an irreversible behavior depends on different response of the particle system between tensile and compressive loadings.
Hebatalrahman A. Hebatalrahman, Saaid I. Zaki
World Journal of Nano Science and Engineering, Volume 10, pp 37-50; https://doi.org/10.4236/wjnse.2020.103004

Abstract:
In recent years, the world of science has started to produce advanced materials and technology in the nanoscale, which known as nanotechnology. The use of nanotechnology has become wide spread in all branches of science, one of the important branches is the field of transportation. The application of nanotechnology in pavements showed great promise and the potential to change commonly used materials, which makes transportation more efficient, smart looking, stronger and durable that all lead to the extension of their life cycle of the roads. So, there is an essential need to prepare advanced nanotechnology tools and detection systems contain very recent instruments needed for nanotechnology studies, since the physical, chemical and biological properties of the material at nanoscale differ in fundamental and valuable ways from that at normal scale. In this work the different techniques in measuring and detection techniques in nanotechnology will be discussed the method of operation and accuracy of each technique will be evaluated, the main applications of each technique in industrial and construction field will be evaluated.
Soonmin Ho, Munir Hayet Khan
World Journal of Nano Science and Engineering, Volume 10, pp 1-13; https://doi.org/10.4236/wjnse.2020.101001

Abstract:
Oil palm is known as Elaeis guineensis, found in Africa, South East Asia and China. Oil palm shell is used to prepare activated carbon because of high carbon content, high surface area, highly developed porosity and low price. During the physical activation, carbonization occurs in order to create porosity in the raw material. Literature review indicated that carbon material was impregnated with chemical agents such as phosphoric acid, potassium hydroxide, sulphuric acid, sodium hydroxide and zinc chloride in chemical activation process. Experimental results showed that the obtained activated carbon was used in hydrogen storage purpose, supercapacitor, gases and liquid phase adsorption process. On the other hand, oil palm shell was used in manufacturing lightweight concrete because of lighter and will not produce toxic substance. The bulk density and compressive strength of oil palm shell-based concrete were 500 - 600 kg/m3 and more than 25 MPa, respectively.
Ana P. Mousinho, Ronaldo D. Mansano, Nelson Ordonez
World Journal of Nano Science and Engineering, Volume 10, pp 27-35; https://doi.org/10.4236/wjnse.2020.102003

Abstract:
In this work, was obtained metallic decorated, single wall Carbon Nanotubes (SWCNTs) using High Density Chemical Vapor Deposition (HDPCVD) system on chromium thin films on a silicon wafers substrate. The characteristics of this deposition method are capacity of the segregation of metallic nanoparticlesas seed for the SWCNT growing. Use of magnetic particle decorated carbon nanotubes increases the applications in magnetic devices, magnetic memory, and magnetic oriented drug delivery. The CNTs’ spectra show a unique emission band, but due to the presence of the chromium, the spectra obtained in this work showed many bands that are related to the CNTs with different diameters. The CNTs obtained by the HDPCVD system are highly aligned and showed metallic features. Results of this work proved the possibility of obtaining the controlled deposition of aligned single-walled CNTs forest films decorated with chromium and suggested future studies in magnetic devices applications.
Luiz Carlos Cordeiro Junior, Élcio Nogueira
World Journal of Nano Science and Engineering, Volume 10, pp 14-26; https://doi.org/10.4236/wjnse.2020.101002

Abstract:
A theoretical analysis of the influence of the flow of a coolant containing silver nanoparticle (Ag) in an automotive radiator is presented. The coolant fluid is composed of water or an aqueous solution of Ethylene-Glycol (EG50%) and silver nanoparticles. Ethylene glycol (EG) has been used in automobile radiators for many years due to its compatibility with metals and its anti-cooling properties. Silver nanoparticles are being incorporated into the development of high-precision surgical equipment. It is shown that the rate of heat transfer increases significantly using silver nanoparticles and ethylene glycol and water. There is a maximum for heat exchange between fluids in all analyzed coolant flows—the maximum moves to higher airflow rates when the coolant flow rate is increased. However, the energy dissipation in the stream also increases, but the relationship between the energy dissipated in the flow and the energy transferred in the form of heat is low, which justifies the use of silver nanoparticles and ethylene glycol, or silver nanoparticles and water as a coolant in the automotive vehicle radiator.
World Journal of Nano Science and Engineering, Volume 09, pp 15-24; https://doi.org/10.4236/wjnse.2019.92002

Abstract:
This computational research study analyzes the increase of the specific charge capacity that comes with the reduction of the anisotropic volume expansion during lithium ion insertion within silicon nanowires. This research paper is a continuation from previous work that studied the expansion rate and volume increase. It has been determined that when the lithium ion concentration is decreased by regulating the amount of Li ion flux, the lithium ions to silicon atoms ratio, represented by x, decreases within the amorphous lithiated silicon (a-LixSi) material. This results in a decrease in the volumetric strain of the lithiated silicon nanowire as well as a reduction in Maxwell stress that was calculated and Young’s elastic module that was measured experimentally using nanoindentation. The conclusion as will be seen is that as there is a decrease in lithium ion concentration there is a corresponding decrease in anisotropic volume and a resulting increase in specific charge capacity. In fact the amplification of the electromagnetic field due to the electron flux that created detrimental effects for a fully lithiated silicon nanowire at x = 3.75 which resulted in over a 300% volume expansion becomes beneficial with the decrease in lithium ion flux as x approaches 0.75, which leads to a marginal volume increase of ~25 percent. This could lead to the use of crystalline silicon, c-Si, as an anode material that has been demonstrated in many previous research works to be ten times greater charge capacity than carbon base anode material for lithium ion batteries.
Diganta Dutta, Roman Schmidt, Samodha C. Fernando, Indrani Ghosh Dastider
World Journal of Nano Science and Engineering, Volume 09, pp 1-14; https://doi.org/10.4236/wjnse.2019.91001

Abstract:
Atomic force microscopy (AFM) is a device that is used for not only high-resolution imaging but also used for measuring forces. It is possible to quantify the surface density change for both colloid and nano probe as well as silica surface. By changing the quantity of ions within a potassium chloride solution, it then becomes possible to evaluate the quantity of ions that attach themselves to AFM colloid probe, nano probe and silica samples. In this study, the force was measured between AFM probes and silica surface in different ionic concentrations. Two different types of AFM probe were used: a colloid probe with a radius of 500 nano-meters and a nano probe with a radius of 10 nano-meters. This study is focused on measuring how the force magnitude, especially electrical double layer force, varied between the two types of probes by changing ionic concentrations. For all test trials, the results agreed with the electrical double layer theory. Although the micron probe was almost an exact match for all ranges, the nano probe was closest within its short-range forces. This is attributed to the formula use when analyzing the electrical double layer force. Because the formula was originally calculated for the micron probe, the shape and size of the nano probe created too many variables for an exact match. Along with quantifying the forces, this experiment allowed for an observation of Van der Waals force making it possible to calculate the Hamaker constant. Conclusively, all results show that the obtained surface charge density increases as the ionic concentration increases. In addition, through the comparison of the results obtained from the nano-sized probe and the micron-sized probe, it was concluded that nano size probe mapped higher surface charge density above the silica surface than the micron-sized probe under the same conditions.
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