Wet-electrochemical growth of CdTe layers for photovoltaic applications

Journal of Materials Science: Materials in Electronics - Cadmium telluride (CdTe) thin films have been prepared using a low-cost potentiostatic electrochemical technique from an aqueous...     

Comparitive investigation of performance and emission features of methanol,ethanol, DEE,and nanopartilces as fuel additives in diesel-biodiesel blends

The usage of biodiesel blends is restricted due to its low fuel consumption and high thermal NOx. The current study exhibits the usage of four different fuel additives methanol, ethanol, diethyl ether, and NiO nanoparticles in Neem biodiesel blend (NB25) to shore up the usage of neem oil methyl ester. Performance and emission experimentation of a compression-ignition engine fueled with NB25 having fuel additives were conducted at varying injection opening pressures (180, 210, and 240 bar) and static injection timings (19°, 23°, and 27° bTDC). The results indicate that when NiO fuel additives were doped in the NB25 blend, high peaks of NOx were found with betterment in performance features with a lower CO and HC emission.     

Real-time investigation on photocatalytic oxidation of gaseous methanol with nanocrystalline WO3-TiO2 composite films

Here we report on our investigation on photocatalytic oxidation (PCO) of gaseous methanol with WO₃-TiO₂ composite films. WO₃ and WO₃-TiO₂ composite thin films were prepared by drop casting method. PCO of gaseous methanol and hydrogen generation process on platinum loaded WO₃-TiO₂ composite thin films in high vacuum were investigated using a home-made reactor with a six-channel quadrupole mass spectrometer at real-time scale under UVA (300-400 nm) light illumination.In the case of Pt loaded WO₃ thin films, PCO of gaseous methanol proceeds through intermediates viz. formaldehyde, CO and finally to CO₂ and H₂. PCO of gaseous methanol occurs via direct hole transfer over Pt loaded WO₃ thin films. On the other hand, PCO of gaseous methanol over Pt loaded WO₃-TiO₂ composite thin films proceeds with competitive direct and indirect hole transfer reactions. Our real-time analysis of gas phase photocatalysis realized the identification of direct and indirect hole transfer processes and the reaction intermediates thereof.     

Anatomy of a rapid pressure swing adsorption process performance

A detailed numerical study of the individual and cumulative effects of various mass, heat, and momentum transfer resistances, which are generally present inside a practical adiabatic adsorber, on the overall separation performance of a rapid pressure swing adsorption (RPSA) process is performed for production of nearly pure helium gas from an equimolar binary (N₂ +He) gas mixture using 5 A zeolite. Column bed size factor (BSF) and helium recovery (R) from the feed gas are used to characterize the separation performances. All practical impediments like column pressure drop, finite gas‐solid mass and heat transfer resistances, mass and heat axial dispersions in the gas phase, and heats of ad(de)sorption causing nonisothermal operation have detrimental impacts on the overall process performance, which are significantly accentuated when the total cycle time of a RPSA process is small and the product gas helium purity is high. These impediments also prohibit indefinite lowering of BSF (desired performance) by decreasing process cycle time alone. © 2015 American Institute of Chemical Engineers AIChE J, 61: 2008–2015, 2015     

In vivo characteristics and localisation of carotenoid pigments in psychrotrophic and mesophilic Micrococcus roseus using photoacoustic spectroscopy

The mesolimbic dopaminergic system (MDS) has been shown to be implicated in feeding behaviors. The present experiment was conducted to examine the effects of the sensory properties of food ingested on MDS activity. Microdialysis coupled to high-performance liquid chromatography with electrochemical detection was employed to measure the extracellular levels of dopamine (DA) and its main metabolites (DOPAC and HVA) in the nucleus accumbens of freely moving rats. During microdialysis sessions rats had access or not to powdered foods varying in palatability: short cakes as highly palatable (HP) food and regular chow as low palatable (LP) food. In the absence of food, there were no alterations in extracellular levels of DA, DOPAC, and HVA. During feeding, DA rose significantly with a greater rise for the HP than the LP food. Levels of DOPAC and HVA only reached significance with the HP food. The results indicate that the MDS is activated on ingestion of food, and suggest that MDS activity is related to the rewarding properties of foods.     

Modeling of heat recovery from a steam‐gas mixture in a high‐temperature sorption process

A high pressure condenser is considered to remove water vapor as well as recover heat from the desorbed steam—CO₂ gas mixture in a novel sorption enhanced reaction process. It is possible to have water condensation at the gas side as well as water evaporation at the coolant water side because of large temperature difference between the hot and cold side. A model of heat and mass transfer and phase change was developed to understand the complex phenomena associated with the simultaneous condensation and evaporation taking place in the unit. A finite difference method was used to solve the boundary value problem. Additional insight was obtained by describing the operating lines and equilibrium condition in an enthalpy diagram. The model was used to explore the performance in terms of the heat recovery. The heat recovery was best at the beginning of the process when the superheated steam was generated. © 2011 American Institute of Chemical Engineers AIChE J, 2012     

Efficiency of Nitrogen Desorption from LiX Zeolite by Rapid Oxygen Purge in a Pancake Adsorber

A nonequilibrium, nonisothermal, nonisobaric model was used for numerical simulation of the efficiency of N₂ desorption from a LiX zeolite column by rapid purge with O₂ in a pancake adsorber. The key parameters included desorption time, adsorbent particle size, and the adsorber length to diameter ratio. The efficiency was found to be a complex function of these variables.     

Enhanced gas sensitivity in TiO2 nanoneedles grown on upright SnO2 nanoplates

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MALDI-TOF mass spectrometry analysis of amphipol-trapped membrane proteins

Amphipols (APols) are amphipathic polymers with the ability to substitute detergents to keep membrane proteins (MPs) soluble and functional in aqueous solutions. APols also protect MPs against denaturation. Here, we have examined the ability of APol-trapped MPs to be analyzed by matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF-MS). For that purpose, we have used ionic and nonionic APols and as model proteins (i) the transmembrane domain of Escherichia coli outer membrane protein A, a β-barrel, eubacterial MP, (ii) Halobacterium salinarum bacteriorhodopsin, an α-helical archaebacterial MP with a single cofactor, and (iii, iv) two eukaryotic MP complexes comprising multiple subunits and many cofactors, cytochrome b(6)f from the chloroplast of the green alga Chlamydomonas reinhardtii and cytochrome bc(1) from beef heart mitochondria. We show that these MP/APol complexes can be readily analyzed by MALDI-TOF-MS; most of the subunits and some lipids and cofactors were identified. APols alone, even ionic ones, had no deleterious effects on MS signals and were not detected in mass spectra. Thus, the combination of MP stabilization by APols and MS analyses provides an interesting new approach to investigating supramolecular interactions in biological membranes.