Fatigure is observed to be one of the major reasons for failure of mechnical components subjected to cyclic load. Micro-alloying of steel is usually done in order to improve its fatigue strength. Micro-alloyed steel contains small quantity of alloying elements such as niobium, vanadium, molybdenum, zirconium, titanium, boron, and rare-earth metals. Motivation of the present work is to find the exact number of cycles to failure for a given stress. The fatigue curve can be described by Gatts equation, exponential function and hyperbolic function. The exactness of each method is checked by three stress level analysis. Gatts equation is a better tool to describe the fatigue curve at high levels of stresses which is near to ultimate stress.

The numerical investigation emphasizes on studying the heat transfer characteristics when a high velocity air jet impinges upon a flat plate having constant heat flux. Numerical analysis has been conducted by solving conservation equations of momentum, mass and energy with two equations based k- e turbulence model to determine the wall temperature and Nu of the plate considering the flow to be incompressible. It was found from the investigation that the heat transfer rate increases with the increase of Reynolds number of the jet (Rej). It was also found that there is an optimum value for jet distance to nozzle diameter ratio (H/d) for maximum heat transfer when all the other parameters were kept fixed. Similar results as above were found when two jets of air were used instead of one jet keeping the mass flow rate constant. For a two jets case it was also found that heat transfer rate over the surface increases when the jets are inclined outward compared to vertical and inward jets and also there exists an optimum angle of jet for maximum heat transfer. Further investigation was carried out for different jetto-jet separation distance for a twin jet impingement model where it was noted that heat transfer is more distributed in case of larger values of L and the rate of heat transfer increases as the separation between the jet increases till a certain point after which the rate of heat transfer decreases.

Pineapple leaf fiber waste carbon, modified with 3% KMnO4, was used for Ca2+ removal from aqueous solution. The effects of contact time, loading, water hardness, and isotherms on Ca2+ adsorption were studied. The results show that the Ca2+ ion removal by pineapple leaf fiber waste carbon could be improved by modification with KMnO4. The adsorption would reach equilibrium state at about 60 min for a water source with hardness values of 40-200 mg/dm3. Increases in total hardness (40 to 200 mg/dm3) lead to a decrease in Ca2+ ion removal efficiency (90.05% to 37.65%) and an increase in Ca2+ ion adsorption capacity at equilibrium (4.37 mg/g to 8.95 mg/g). The Ca2+ removal efficiencies increase with increasing loading of modified waste carbon. The equilibrium data were fitted well by both the Langmuir isotherm and the Freundlich isotherm. For the Langmuir isotherm model, the values of the maximum Ca2+ adsorption capacity and Langmuir constant being 2.81 mg/g and 0.9262 dm3/g, respectively. On the other hand for the Freundlich isotherm model, the KF and n values are 1.374 dm3 (1/n) mg (1-1/n)/g and 4.671, respectively. These results indicate that modified pineapple fiber waste carbon is a material with high Ca2+ ion adsorption capacity, heterogeneity, and high affinity.

The aim of this paper is to focus on the effect of cryogenic treatment on the microstructure, mechanical and wear properties of Al 6061 and Al 8011. The first objective was to understand the degree to which wear behaviour has shown improvement with aluminium grades being treated cryogenically on the specimens. To conduct wear test Aluminium experimental investigation has been carried out on aluminium alloys with cryogenic coolants. The cryogenic coolant has increased the wear resistance properties of aluminium upto 25% when compared to wear of non-cryogenically treated aluminium. The cryogenic treatment was carried out under three different timings for three different rpm’s under varying loads. The paper also studies the micro structural changes under these varying conditions. The experimental investigation of the paper concludes that cryogenically treated aluminium shows increase in wear resistance of nearly 25%.

The transcription factor, Regulatory Factor X, 6 (RFX6), is almost exclusively found in pancreatic islets where it maintains the functional identity of ß-cells. It regulates insulin secretion directly by binding to the insulin promoter and indirectly by altering the expression of components of the voltage-gated ion channels. In order to better understand the mechanics of this binding, the present study describes the over expression and purification of the human RFX6 DNA binding region (RFX6 DBR) in a prokaryotic system. Using the pET28a(+) vector and E.coli host systems, a C-terminal His-tagged, 11kDa recombinant RFX6 DBR was expressed and purified. The identity of the protein was confirmed by Western blot analysis. The RFX6 DBR is able to bind to a 450bp insulin (INS) promoter segment in vitro with an approximately 4x108 molar excess of protein required for the short-lived binding of protein to DNA. The basic molecular characterization of the RFX6 DNA binding region whose mutation causes certain forms of neonatal and type 2 diabetes, is reported here for the first time. The present study could have implications in understanding RFX6 as a target of pharmacological intervention.

We develop new approach to produce carbon nanostructures, by using biomass as precursor, hydrothermal pretreatment and microwave pyrolysis as preparative methods. The crystallography and surface functionalities of carbon sheets were analyzed based on x-ray diffraction and FTIR data. The electrical conductivity was examined by using Kelvin methods. The electrochemical behavior tests were carried out upon binderies carbon pellet using cyclic voltammetry method of three electrodes system. FTIR analysis showed that the existence of C=C in aromatic of carbon vibration in 1100 – 1300 cm-1, carboxyl – carboxylate bonding vibration in 1600 cm-1, O-C=O and O-C=N bending vibration in 1600 – 2500 cm-1 and hydroxyl-carboxyl bond. XRD analysis showed that the hydrothermal treatment eliminated the character of the basal plane of carbon. The crystal structure of carbon was only detected for edge plane (002). The carbon has 0.039 Scm-1 of electrical conductivity. The shapes of voltammograms were relatively rectangular which meant that carbon electrode underwent dominantly non-faradaic or electrical double layer process. All voltammograms showed the existence of electrical double layer characteristic ranging from 10.3 to 23.2 mFg-1. The highest electrical current can be obtained using base electrolyte (KOH).

Highly porous KOH–activated carbon was successfully synthesized from rice husk by chemical activation with KOH. The products were characterized by IR, SEM, and BET. The response surface methodology (RSM) was employed to determine the optimum fabrication conditions of AC with respect to the simultaneous effects of activation temperature (T), impregnation rate (IR) and activation time (t) to maximize the yield of activated carbon and removal efficiency of Ni2+. The optimum synthesis conditions were T = 522 oC, IR = 1.3 and t = 360 min with a maximum AC yield of 28.5 % and a maximum Ni2+ removal of 28.5 %. The results indicated that highly porous structure, high surface area as well as the surface functional groups are key impacts in the adsorptive capacity of activated carbons for Ni2+.

The amorphous carbon thin films of 500 nm thickness was deposited on Si (100) and stainless steel (SS) substrates by filtered cathodic vacuum arc (FCVA) technique. The 100 nm chromium interlayer was deposited by R.F. magnetron sputtering system to improve the adhesion strength between the substrate and the film. The Raman study showed the broad peak ~1560 cm-1 indicating the amorphous carbon. The AFM studies revealed the smooth morphology of the films with small surface roughness. The wear studies indicated the low friction coefficient of ~0.14. The carbon films prepared on stainless steel indicated the upper critical load of 11 N and the hardness value of 27 GPa a with the young’s modulus of 240 GPa.

Concrete is the most sought after material due to increase in construction activities and infrastructural developments. Availability of natural sand is decreasing thereby increase in the cost of construction. In the present work undertaken, an attempt has been made to give an alternative to natural sand. Optimization of replacement of natural sand with manufactured sand in concrete, durability studies such as water absorption, rapid chloride permeability test, sorptivity, acid resistance, alkaline resistance, impact resistance and abrasion resistance of M40 and M50 grades of concrete have been studied with manufactured sand as fine aggregate and compared the results with the conventional sand concrete. The results shows that there is an increase in the durability properties up to 70 % level of replacements of sand with manufactured sand as fine aggregate and for 100 % use of manufactured sand also gives the better durability than the conventional sand concrete.

A simple bio-template assisted ultrasound synthesis method is followed for the preparation of pure and Dy3+ (1-11 mol %) doped MgSiO3 nanophosphors. Various experimental parameters influences in controlling the shape, size and morphology of the obtained products. The final product is well characterized by powder X-ray diffraction (PXRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM) and photoluminescence (PL). It is noticed that the morphology of the product was highly dependent on the surfactant (mimosa pudica) concentration, sonication time, pH and sonication power. The formation mechanism for various micro/nano superstructures is proposed. The characteristic photoluminescence peaks are observed at 484, 574 and 666 nm due to the electronic transitions 4 F9/2 ? 6Hj (j=15/2, 13/2, 11/2) of Dy3+ ions upon excited at wavelength of 350 nm [6H15/2 ? 6 P7/2 (4M15/2)]. The photometric studies indicate that the obtained phosphors may be promising compounds in white light emitting diodes (wLED’s). The present synthesis route is rapid, environmentally benign, cost effective and useful for industrial applications such as solid state lighting and display devices.

NA

The solar chimney is a passive device that is applied to enhance room ventilation. The chimney could be vertical or inclined. The chimney inclination angle and air inlet opening position are important parameters that greatly affects flow pattern and ventilation rate inside the room. In this study, the effect of air inlet opening position and chimney inclination angle on air change per hour and air flow pattern inside the room was numerically investigated. A numerical simulation using CFD code was used to predict flow pattern. Then the results were compared with published experimental measurements. Find out the effect of air inlet opening position and inclination angle of chimney on mass flow rate at outlet of the chimney.