材料科学および工学ジャーナル

The present work highlights the influence of gamma-radiation on Cu2InSnS4 (CITS) thin films deposited by spray pyrolysis technique. Irradiation treatment was carried out by different doses (20-40-60-80 and 100 kGy) of γ-radiation using Co60 as source. The physical investigations of samples were demonstrated using energy dispersive X-ray spectrometry (EDX), X-ray diffraction (XRD), Maud software, scanning electron microscopy (SEM), Spectrophotometer and Drop Shape Analysis System. Firstly, XRD patterns reveal a decrement in peak intensities followed by the division of peaks related to (204) and (312) lattice plans after gamma-radiation. All films were crystalized into stannite structure and the crystallites were orientated towards (112) plan. Secondly, EDX spectroscopy reflects an appreciably decrease in Cu, In, Sn and S contents. SEM micrographs clearly show a total morphological modification from nanospherical to pyramidal shapes at 60 kGy, hierarchical rods and lamellar shapes at 100 kGy. Therefore, a special emphasis has been focused on surface wettability of irradiated films, which point out the hydrophilic surface after irradiation. As known, hydrophilic character has a notable beneficial role on photocatalytic activity that may be due to the active surface area and the adsorption of dye. Based on the relationship between hydrophilicity and photocatalysis, we have confirmed experimentally the better capacity of irradiated CITS thin film with 60 kGy to decompose Rhodamine B (RhB) dye under Xenon irradiation. Long-term runs confirm the stability of irradiated CITS with 60 kGy for photocatalytic process after an overall duration for 5h:30 (4 cycles of 120 min each). This result demonstrates that irradiated CITS with 60 kGy may considered as an efficient stable photocatalyst for the remediation of water polluted.

Materials researchers work with different kinds of materials (e.g., metals, polymers, ceramics, fluid precious stones, composites) for a wide scope of uses (e.g., energy, development, gadgets, biotechnology, nanotechnology) utilizing current preparing and revelation standards (e.g., projecting, added substance producing, covering, dissipation, plasma and radiation handling, man-made brainpower, and programmatic experiences).

In today’s world one of the major problems is pollution. In order reduce the pollution we need sustainable solution this sustainability includes socio economical equity. and environmental protection. To achieve sustainable solution, these three issues must be solved. Titanium dioxide blended concrete is the most promising solution for this ever increasing problem. This concrete has the same structural properties to normal concrete but because of the presence of titanium dioxide in the concrete which removes the pollutants effectively. This solution provides a viable option to high traffic volume roads or areas. The smog absorbing or photocatalytic concrete acts as pollution reducer. It means which converts harmful pollutants into harmless pollutants. In our project we are making concrete blocks by replacing the cement with titanium from 0% to 5% and we tested the blocks for compressive strength and smog absorbing test to know the number of pollutants absorbed by the concrete blocks by using Multi Gas Analyser machine and we compare the results with normal concrete.

Metal forming process such as extrusion, rolling, sheet metal forming etc. where the work piece are subjected to finite strain and stress. Metal forming is an ancient art and is a vast subject of closely guarded of secrets in antiquity. In many respects the old craft traditions have been retained until present time. Unfortunately, a series of problem arises when commissioning a new production or when changes made from one well known material to another. Current trends towards adaptive control and flexible manufacturing systems call for more precise definition and understanding of the process. This will ensure much better control over a production, dimension and quality. Practical test to determine the best tool shape and forming condition can be very expensive and wasteful of tool and work piece material. Many cases of simple component forming operations may result in cracking during production or become weakened by high residual stress. In view of above, aluminum sheet metal forming has been active subject for the past three decades and current trends indicate importance of the sheet metal forming operation, since it has applications in automotive and aero industries. Major problem in aluminum sheet metal forming operation were deformability and spring back effect. Deformation errors and spring back effect are dependent on the number of parameters such as die and tool geometry, friction condition, loading condition and anisotropic properties of the metal. Computer modeling of sheet metal forming of aluminum sheet metal will help in predicting deformity error and spring back effect which saves lot of money and time due to the prediction gives accurate results.

This paper discusses a new method to prepare boron doped carbon (CBx) material with some substitutional boron atoms homogeneously distributed in the highly graphitic structure. The chemistry involves a mesophase boron-doped pitch (B-Pitch) prepared by mixing a borane reagent (i.e., dichlorophenylacetylborane) with petroleum pitch at 400°C. The resulting mesophase B-Pitch was further diluted with the starting pitch to adjust its softening temperature and melt viscosity, they are essential during the preparation of C/C composites. A resulting B-Pitch/Pitch blended precursor with 3.3 mol% B content and a softening temperature of 300°C was directly converted to CBx CBx CBx CBx B2O3 surface layer to slow down the oxygen diffusion into the matrix and stability. CBx) CBx at 2300°C under argon atmosphere, showing a char yield of 81%. The presence of a small percentage of B atoms in this B-Pitch/Pitch precursor catalyzes the carbonization/graphitization to form a highly graphitic CBx structure. Compared to synthetic graphite, which is stable in air up to 500°C, the resulting CBx shows higher thermal-oxidative stability. In air at 600°C, no weight loss was observed after 6 hours. At 700°C and 800°C, there was no detectable weight loss for 80 minutes. Evidently, the homogeneous distribution of B atoms in the CBx matrix is essential in continuously providing a protective B2O3 surface layer to slow down the oxygen diffusion into the matrix and delay the thermal/oxidative degradation process. Overall, this new precursor technology may offer the C/C composite manufacturing with reduced pyrolysis cycles and increased thermal/oxidative stability in high temperature applications.

Hollow nanostructured materials have gained attraction due to their advantages in stability, enlarged surface area and enhanced electrochemical performance toward supercapacitors. In this study, we describe the synthesis of hollow polyaniline spheres (HPS) by one pot polymerization process using FeCl3 as a catalyst and H2O2 as oxidizing agents under hydrothermal conditions. The HPS are further activated by using potassium hydroxide (KOH) and heat treatment under N2. The obtained results have demonstrated that activated HPS samples possess unique well- balanced hierarchical porous structure with mesopores and micropores combination. Besides, activated HPS own easy-accessibly large surface area and high conductivity, which can result in ultrafast electrolyte ion transport and endow carbon materials outstanding capacitive performance. Furthermore, the KOH activated HPS exhibits a larger specific surface area of 311 m2 g–1, specific capacitance of 945 F g–1 at scan rate 2 mV s–1, high energy density 126 Wh kgâ??1 at 1 A gâ??1 current density and capacitance retention (96%) after completing 1000 cycles in 1.0 M KOH aqueous solution, indicating that HPS are a promising electrode material for high performance supercapacitor application

One of the basic needs in the defense industry is the manufacturing of thin-slice and high-plasticity pieces, but thin-slice pieces with complex geometric shapes can often not be manufactured by conventional ways or cost more than conventional ones. Usually, the method of manufacturing these pieces is to use the spinning. In addition to quality and precision in size, these pieces must be of high strength, which makes them difficult to manufacture. In this study, spinning with thermal methods in High Temperature Furnace was used to form a bowl. The Hastelloy x alloy was used for fabrication. All tensile, hardness and microstructure tests were performed on the formed part by optical microscopy after forming and heating processes. After completing the process of manufacturing, the quality of its dimensions were also measured by a 3D optical scanner. The Hastelloy x alloy loses its plasticity after 45% cold-working, which significantly reduces elongation and increases hardness. The furnace at 1177°C was used to increase the workability. The use of the furnace results in full recrystallization of the microstructure, reducing the hardness by 62 percent, increasing by 6 times the elongation, and by 40 percent the yield stress, which provides the conditions for further cold work. Experimental examination of surface quality using optical scanners shows that the average thickness distribution obtained for this experiment is 0.13. This value represents only a difference of less than 15% with the value obtained by software 0.15, indicating that the dimension produced is in good agreement with the sample.

Recent innovations in engineered materials have been leveraged to augment the field of flexible electronics. Flexible electronic devices are often lightweight, portable, less expensive, environment friendly, and disposable. Flexible electronics systems require the integration of flexible and stretchable antennas operating in specific frequency bands to provide wireless connectivity, which is necessity in today’s informationoriented society. The markets for flexible wireless devices are rapidly increasing partly due to the demands in wearable and implantable devices for health-monitoring systems and daily-life wireless devices. For this reason, the need for flexible printed antennas has increased in recent years, especially for biomedical applications. This paper focuses on the need for flexible antennas, materials, and processes used for fabricating the antennas, various material properties influencing antenna performance, and specific biomedical applications accompanied by the design considerations. After a comprehensive treatment of the above-mentioned topics, the paper will also focus on inherent challenges and future prospects of flexible antennas. Finally, an insight into the application of flexible antenna on future wireless solutions is discussed

Synthesis of 3-[3-(2,3-dichlrophenyl)prop-2-enyl]-2H-chromen-2-one is a heterocyclic organic crystal using Claisen-Schmidth condensation reaction. Functional group present in the sample was investigated by their vibrational modes using FTIR spectrometer. Thermal stability of crystal was investigated by thermogravimetric analysis. UV absorption of crystal was determined by Shimadzu UV- 1800 spectrometer wavelength range from 400 to 4000cm-1.

Surface defect control is the serious science in semiconductor industry. Surface defects found at the end product of silicon wafer manufacturing are generated by human, fab facility, equipment and process. Generally, the surface defects found on a silicon wafer could be classified as grown-in Crystal Originated Particles (COPs), Surface-Adhered Foreign Particles (SFPs), and Process-Induced Defects (PIDs). Making the correct defect classification by the surface scanning instrument is of paramount because it provides the opportunity for finding defect root cause, which is part of yield enhancement process. This article reveals a novel defect classification approach by optimizing the linear-based channeling and rule-based binning algorithms applied in KLA surface scanning counter, a commercially available surface defect metrology tool.