Journal of Material Sciences & Engineering

Organo-gels with a series of biscarbamates as gelators were prepared using microwave (MW) heating source as well as conventional heating. Biscarbamates with alkyl side chain lengths varying from C5 to C18 were used, with six solvents having dipole moments ranging from 0.07 to 4.3 D. The minimum gelation concentration and the time required for dissolution were significantly reduced with MW heating with benzonitrile, compared to the conventional heating for all the side chain lengths of the biscarbamates. While such reduction was pronounced with benzonitrile and dimethyl sulfoxide with large dipole moments, the time required for dissolution increased with MW heating (compared to the conventional) in the case of xylene and toluene with small dipole moments. Thus, MW is effective with solvents possessing large dipole moments. Although the gels consist of fibers using both methods, an inherent orientation of these fibers was seen with MW heating.

In this study, we report on the synthesis of a new AB3-type compound LaZr2Mn4Ni5 (with a content of 40 wt %) at room temperature during 5h of mechanical alloying. This compound was synthesized from the two binary compounds LaNi5 (CaCu5-type structure, P6/mmm space group) and ZrMn2-Laves phase (MgZn2-type structure, P63/mmc space group) in order to take advantage of the hydrogen absorption properties of these two types of intermetallic compounds. Structural properties were investigated using X-ray diffraction (XRD). The surface morphology of the cycled electrode was observed by a scanning electron microscope (SEM). The electrochemical properties of the LaZr2Mn4Ni5–based alloy were determined using the chrono-potentiometry method. The experimental results indicate that the discharge capacity reaches a maximum value of 300 mAh/g. Solid-gaz reaction shows that this compound is able to form the LaZr2Mn4Ni5H13 hydride at room temperature at an absorption plateau pressure of about 7 bar.

Polymer gels based on polyaspartic acid (PAsp) and polyacrylic acid (PAA) have been synthesised using ethylene glycol dimethylacrylate (diacrylate-EGDMA) and Trimethylolpropane triacrylate (Triacrylate-TMPTA) as cross-linkers. Swelling behaviour of these polymers has been studied in different solutions like glucose, saline and water. The swelling behaviour of these polymers has also been studied under different pH conditions. The swelling capacity has also been analysed under load to have an idea of the gel strength (Absorbency under Load-AUL). Best absorbing characteristics, as indicated by the swelling behaviour, have been observed in case of polymer gels synthesized with EGDMA. Polymers with maximum PAsp have shown maximum superabsorbent properties in case of EGDMA as a cross-linker. However, with TMPTA as a cross-linker molar mass ratio of 1:2 polyaspartic acid: acrylic acid have shown better results. These polymers have better superabsorbent characteristics. TMPTA based polymers have shown better properties under load than EGDMA These polymers can be used as smart polymers for various applications e,g., drug delivery, materials for wound dressings, etc as they have shown varying behaviour in different conditions. The structure of the polymers has been studied by FTIR (Fourier Transform Infrared spectroscopy) and NMR (Nuclear Magnetic Resonance Spectroscopy). The surface morphology has further supported the results.

Thermal barrier coating (TBC) system is used in both aero engines and other gas turbines offer oxidation protection to super alloy substrate component. In the present work, it shows the ability of a new fabrication technique to develop rapidly new coating composition and microstructure. The compact powder were prepared by powder metallurgy method involving powder mixing and the bond coat was synthesized through the application of spark plasma sintering (SPS) at 1100°C, 1050°C and 1100°C to produce a fully dense 94%) Ni22Cr11Al bulk samples. The influence of sintering temperature on hardness of Ni22Cr11Al done by micro vickers hardness tester was investigated. And oxidation test were carried out at 1100°C for 20 hr, 40 hr and 100 hr. The resulting coat was characterised with Optical microscopy, Scanning electron microscopy (SEM) and X-ray diffraction (XRD). Micro XRD analysis after the oxidation test revealed the formation of protective oxides and non-protective oxides.

In this study, Polyaniline-ignimbrite (PAN-IB) which is a novel nanocomposite material consisting of electrically conductive Polyaniline (PAn) polymer and Ignimbrite (IB) natural insulating material was synthesized chemically using KIO3 as a radical initiator in aqueous media with conventional radical polymerization method. The synthesized nanocomposites including ignimbrite with various monomer-ignimbrite percentages were monitored with scanning electron microscopy (SEM) and structural characterizations were examined with FTIR spectroscopy. Thermogravimetric analysis (TGA), particle size analysis with dynamic light scattering, magnetic susceptibility and conductivity measurements were also examined for all synthesized composites. With making a composite with aniline, the conductivity of ignimbrite (3 × 10-7 Scm-1) reached to 2.7 × 10-5 Scm-1. However increasing the ratio of monomer which is added to ignimbrite did not make a significant change on conductivity of the resulting composite.

Embolization is a minimally invasive treatment that specifically blocks the arterial blood flow into a target blood vessel bed, which is usually a benign or malignant tumor. The aim of the procedure is to shrink the tumor and/or to retard its growth. Embolization the injection of embolic particles via a catheter tube, of which the tip has been navigated carefully (under X-ray guidance) into an arterial branch that exclusively feeds the tumor, and no surrounding healthy tissues. Most of the clinical experience with embolization relates to treatment of leiomyomata (benign tumors growing in the wall of the uterus). There is solid evidence that catheter-based embolization of leiomyomata provides a fully acceptable therapeutic alternative for much more demanding surgical procedures (i.e., hysterectomy and myomectomy). Embolization offers much faster recovery, possible options to become pregnant, and considerable cost saving. There are several commercial brands of embolization agents, suitable to treat leiomyomata. We hypothesized, some years ago, that these products are suboptimal, and that embolization of leiomyomata may be improved further through better engineering of the embolic particles. We developed injectable radiopaque polymer microspheres, which can be monitored during and after the embolization procedure. The embolic microbeads are X-ray traceable, and this has been achieved without compromising other essential properties, such as structural stability and excellent biocompatibility. Herein, we describe new the features of the new embolic microspheres, as observed in preclinical experiments and in the first clinical cases. It is mentioned briefly that this work became an example of successful translation: it has led to a new medical device (Class-IIB) that is now CE-certified and commercially available throughout Europe.

World always asks for compact and effective equipment. For that we need suitable materials. Now think about the thinnest material which has extraordinary properties. Graphene is real two dimensional material. It has lots of useful properties like conductivity, high strength and good flexibility. This Material has lots of potential, but still there is no more researches occupied on Graphene. This research paper is about to introduce the Graphene to the present world and to shows the impotency of Graphene in future. But question arise that which type of equipment or machines need a Graphene, where we can use Graphene to increase the effectiveness of equipment. It has carbon as raw material so it is cheap, eco-friendly and sustainable. It is much stronger, transparent and good conductive material which can use in Conductors, Transistor, Heat spreader and Interconnect wires of Integrated circuits, super capacitors and also useful as micro sensor and actuator. In future with use of Graphene composite, we will able to make space elevator of 36000 km altitude. But still it has some challenges that we have to solve. Challenges like, High prize at this moment (1 cm2 = 3700 rupees), Sensitive to environment with no effective passivation, High quality thin films still lacking of reproducibility, Large scale transfer of films still irreproducible, Sheet resistance still too high, No band gap which a transistor requires (turn off problems). This paper give you total overview of the all basic information require using Graphene in the future. This paper has all basic information regarding to every properties of the Graphene. Here all properties are equally justified on the bases of application too.

This study was conducted to characterize the extracellular polymeric substances (EPS) produced by growing Cloacibacterium normanense in wastewater sludge alone and fortified crude glycerol. The EPS highest concentration of 17.5 g/L was produced using 25 g/L sludge suspended solids supplemented with 25 g/L of crude glycerol. Galactose and Glucose was the main compound of EPS produced with or without crude glycerol, respectively. EPS FTIR spectra revealed a variation in the different functional groups such as amines, carboxyl, and hydroxyl groups for EPS produced. Different functional groups were observed in the EPS produced with or without glycerol. The EPS exhibited kaolin flocculation activity up to 95% and was stable at high temperature. The high viscosity bioflocculant properties of EPS make it suitable for potential industrial applications

One-dimensional nanostructures are of particular interest in nanoelectronics because of the ease with which they can be utilized in fabricating nanodevices where their long axis facilitates contact to the structure, while the short axis preserves the quantized nature of electronic levels. It is therefore desirable to synthesize precisely controlled semiconductor and metal nanowires to study their properties. With much advancement achieved in producing high quality and appreciably controlled semiconductor nanowires, approaches to precisely control the dimensions of metal nanowires still needs to be explored. Here, we have investigated room-temperature sensing properties of these gold nanowires for hydrogen, ethanol and NH3. The sensitivity and selectivity of the wires for sensing different gases are explored. The sensing devices were fabricated by drop-casting the nanowire dispersion over pre-patterned electrodes ultimately paving the path for cost effective applications of these nanowires. Simple chemical routes and solution processing techniques has been utilized for their subsequent device applications. The driving force behind the solution processed devices is their low cost, large device area, physical flexibility and compatibility with the existing technologies.

Frequent use of various types of green composite in different applications has led to the great development in material science technology. Coconut shell which is generally considered waste material is been analysed here to get its desired properties and characteristics. Basically composite particles are studied using various macroscopic and microscopic approach and with various advance techniques like Scanning electron microscopy (SEM), Water absorption and Thickness swelling test, Thermal analysis, Thermo Gravimetric analysis (TGA) and Differential thermal analysis (DTA). In our work we have focused on the thermal analysis of coconut shell particles using TGA and DTA technology and finally the conclusion is made regarding the feasibility of using Coconut Shell Particle in Application of green composites.

This work aims at determination of optimum drilling process design for hybrid structures of polymer composites over titanium alloy in order to reach the needed quality and cost effectiveness for the aerospace industry. A set of experiments are designed to investigate the effects of process variables on the required torques and thrust forces and quality of the drilled holes. Surface response methodology is used to analyze the results. Process maps are introduced based on the experimental results and the optimum conditions for producing quality holes. Evaluation of the presented approach for process design is conducted using carbon fiber reinforced epoxy (IM7/977-3) composites over 6Al-4V titanium alloy (AB1) structure. The proposed study helps in approving the effectiveness of the new approach and in exploring the global optimum drilling parameters for damage free production of aerospace hybrid structures.

In this paper we present results of transport critical current density (Jc) at 20 K and 4.2 K, irreversible magnetic field (Birr), upper critical field (Bc2), critical temperature (Tc), pinning force (Fp), scanning pinning force scaling results (Fp/Fpmax and B/Birr) and electron microscope (SEM) images of un-doped MgB2 wires of 0.63 mm diameter. All wires were annealed at pressures ranging from 0.1 MPa to 1 GPa for 15 min between 680°C to 740°C. SEM images show that 1 GPa pressure yields small grains, higher MgB2 material density, and small voids. The results obtained by a physical properties measurement system (PPMS) show that high pressure (1 GPa) and 700°C annealing slightly decreases Tc above 27 K and increases Tc and Birr below 25 K. Un-doped MgB2 wire annealed in 1 GPa for 15 min at 680°C at has a 20 K, 4.5 T Jc of 100 A/mm2 in and a Birr of 7 T. At 4.2 K, this wire has Jc of 100 A/mm2 at 10.5 T. Scaling results show that the dominant pinning mechanism is point pinning for undoped MgB2 wires under 1 GPa pressure and annealed at 680°C (at 20 K).

This article focus on the study of Transition or Back wall Temperature behavior in PAN based composite materials with and without Silicon Carbide filler was investigated. PAN fabric is one of the most useful reinforcement materials in the composites, its major use being the manufacture of components in aerospace, automotive and missile technology. In this study, PAN carbon fabric laminates were prepared by Hand lay-up technique with and without Silicon Carbide filler. The experimental work was done on studying the Transition or Back wall Temperature characterization and ablative studies through Oxy-acetylene testing. The study results revealed that it exhibits the better thermal protection shield in PAN based Silicon Carbide filler laminate compared without adding filler material. However, the ablation rate study results were exhibits better erosion rate of CP laminate with Sic filler for thermal insulation.

Rapid Advancement in the field of advance Biocomposite has attracted large number of researchers to diagnose and expand the use of light weighted and environment friendly materials for various applications. In this work, depolymerized natural rubber (DNR) was prepared and used as toughening agents for epoxy resin and almond shell particles are filled in modified epoxy resin as reinforcing material. Further, different tests including Tensile Test, Compression Test, Hardness Test, Impact Test etc. were performed to diagnose the effect of various weight percentage (wt%) of composition of blended DNR for achieving maximum toughness and then its effect on treatment with different weight percentage of Almond Shell Particle. Results were analyzed and finally the conclusion is made based on the experiments.

This study investigated the use of polymer derived from oleic acid for coating iron oxide nanoparticles. The purpose of this study was to provide the magnetic nanoparticles an appropriate surface for stabilization in organic solution. The magnetic nanoparticles coated were produced by mixing of the polymer solution with the ferromagnetic fluid by mechanical stir, followed by magnetic separation. These nanoparticles generated a core-shell behavior, in which the core provides the magnetic properties and the external layer formed by the polymer. The interaction between iron nanoparticles and oleic acid polymer occurred by the affinity of carboxylic group. This interaction makes the nanoparticles hydrophobic, moving to the organic media. The carbon content of the coated nanoparticles was approximately 14%, when analyzed by scattering electron microscopy (SEM–EDX), and 12%, when analyzed by Elemental Analysis of carbon, hydrogen and nitrogen. This percentage confirms the presence of the polymer on the surface of magnetic nanoparticles. The average diameter of the coated and uncoated nanoparticles obtained by transmission electron microscopy was around 13 nm and 11 nm and the average diameter of crystallite by X-ray diffraction was around 8 nm and 12 nm respectively. Averaging all this values we obtain 11 ± 2 nm. The thermogravimetric analysis showed the degradation temperatures starting from 200°C to 500°C, attributed to the polymer, and another one degradation temperature between 650-750ºC, relative to the polymer-nanoparticles interaction. Furthermore, the vibrating sample magnetometer indicated that coated nanoparticles remain magnetic, with increasing saturation magnetization value, when a magnetic field was applied.

\r\n

The surface behaviors of monolayers of the poly(itaconate) derivatives, poly(dibenzyl itaconate) (PDBzI) and poly(monobenzyl itaconate) (PMBzI), at the air-water interface were investigated at 298 K on an aqueous subphase at pH 5.7 and 3.0. The monolayer characteristics of PDBzI and PMBzI were studied and compared in terms of surface pressure-area (-A) isotherms, surface compressional modulus-surface pressure (Cs-1-π) curves, static elasticity-surface concentration curves (-), hysteresis phenomena and phase images observed with a Brewster angle microscope (BAM.). The results showed that PMBzI and PDBzI gave rise to stable monolayers and that the isotherms presented pseudoplateau regions at different surface pressure values independent of pH. The PMBzl pseudoplateau region may because a change in the lateral packing of the chains. The PDBzl pseudoplateau region is attributed to a phase transition. The morphology of these monolayers was studied by Brewster angle microscopy (BAM). The surface pressure was expressed in terms of the scaling laws as function of surface concentrations. It can be concluded that the air-water interface was a poor solvent for both studied polymers. The degree of hydrophobicity of the polymers was estimated by determining the surface energy values based on wettability measurements.

Influence of neutron irradiation on reactor pressure vessel (RPV) steel degradation are examined with reference to the possible reasons of the substantial experimental data scatter and furthermore -nonstandard (non-monotonous) and oscillatory embrittlement behavior. In our glance this phenomenon may be explained by presence of the wavelike recovering component in the embrittlement kinetics. We suppose that the main factor affecting steel anomalous embrittlement is fast neutron intensity (dose rate or flux), flux effect manifestation depends on state-of-the-art fluence level. At low fluencies radiation degradation has to exceed normative value, then approaches to normative meaning and finally became sub normative. Data on radiation damage change including through the ex-service RPVs taking into account chemical factor, fast neutron fluence and neutron flux were obtained and analyzed. In our opinion controversy in the estimation on neutron flux on radiation degradation impact may be explained by presence of the wavelike component in the embrittlement kinetics. Therefore flux effect manifestation depends on fluence level. At low fluencies radiation degradation has to exceed normative value, then approaches to normative meaning and finally became sub normative. As a result of dose rate effect manifestation peripheral RPV’s zones in some range of fluencies have to be damaged to a large extent than situated closely to core. Moreover as a hypothesis we suppose that at some stages of irradiation damaged metal have to be partially restored by irradiation i.e. neutron bombardment. Nascent during irradiation structure undergo occurring once or periodically transformation in a direction both degradation and recovery of the initial properties. According to our hypothesis at some stagem(s) of metal structure degradation neutron bombardment became recovering factor. Therefore self-recovering section of RPV steel radiation embrittlement kinetics is an indication of material smart behavior. As a result oscillation arise that intern lead to enhanced data scatter. Disclosure of the steel degradation oscillating is a sign of the steel structure cyclic self-recovery transformation as it take place in self-organization processes. This assumption has received support through the discovery of the similar “anomalous” data in scientific publications and by means of own additional experiments. Data obtained stimulate looking-for ways to management of the structural steel radiation stability (for example, by means of nano-structure modification for radiation defects annihilation intensification) for creation of the intelligent self-recovering material. Expected results: - radiation degradation theory and mechanisms development, - more adequate models of the radiation embrittlement elaboration, - methods and facility development for usage data of the accelerated materials irradiation for forecasting of their capacity for work in realistic (practical) circumstances of operation, - search of the ways for creating of the stable under neutron irradiation self-recovery smart materials.