Enhanced heterogeneous ferrioxalate photo-fenton degradation of reactive orange 4 by solar light

A combined homogeneous and heterogeneous photocatalytic decolourisation and degradation of a chlorotriazine Reactive azo dye Reactive Orange 4 (RO4) have been carried out using ferrous sulphate/ ferrioxalate with H₂O₂ and TiO₂-P25 particles. Solar/ferrous/H₂O₂/TiO₂-P25 and solar/ferrioxalate/H₂O₂/TiO₂-P25 processes are found to be more efficient than the individual photo-Fenton and solar/TiO₂-P25 processes. A comparison of these two processes with UV/ferrous/H₂O₂/TiO₂-P25 and UV/ferrioxalate/H₂O₂/TiO₂-P25 reveals that ferrioxalate is more efficient in solar light whereas ferrous ion is more efficient in UV light. The experimental parameters such as pH, initial H₂O₂, Fe²⁺, ferrioxalate and TiO₂-P25 concentration strongly influenced the dye removal rate in solar processes. The optimum operating conditions of these two combined processes are reported.     

A novel nanostructured iron oxide-gold bioelectrode for hydrogen peroxide sensing

Fe(3)O(4) nanoparticles covalently linked to a gold electrode have been used for immobilizing catalase (CAT) enzyme to sense the presence of various concentrations of H(2)O(2). These nanoparticles ranging from 20 to 30 nm were synthesized by thermal co-precipitation of ferric and ferrous chlorides. SEM and XRD have been used for morphological and structural characterization of Fe(3)O(4) nanoparticles. CAT enzyme was linked covalently to the surface of iron oxide using carbodiimide in phosphate buffer (pH 7.4) at 4?°C. The enzyme-iron oxide link was confirmed by FT-IR spectroscopy. Sensing studies carried out using cyclic voltammetry showed a linear response of the CAT/nano Fe(3)O(4)/Au bioelectrode towards H(2)O(2) between 1.5 and 13.5 μM with a very sharp response time of 2 s.     

Estimation of wind power availability in Tamil Nadu

Eleven years' daily wind speed data at 21 locations in the state of Tamil Nadu, India were analysed to assess the available wind power potential using Weibull distribution under two different methods. The mean wind speed varied from 1.0 to 5.0 m/s dividing the state into four regions. Judged by mean and standard deviation of available wind power, six locations have been identified as possible sites for a wind energy system.     

As(V) removal using carbonized yeast cells containing silver nanoparticles

The present study involves the development of adsorbent containing silver nanoparticles for arsenate removal using silver reducing property of a novel yeast strain Saccharomyces cerevisiae BU-MBT-CY1 isolated from coconut cell sap. Biological reduction of silver by the isolate was deduced at various time intervals. The yeast cells after biological silver reduction were harvested and subjected to carbonization at 400 °C for 1 h and its properties were analyzed using Fourier Transform Infra-Red spectroscopy, X-ray diffraction, scanning electron microscope attached with energy dispersive spectroscopy and transmission electron microscope. The average size of the silver nanoparticles present on the surface of the carbonized silver containing yeast cells (CSY) was 19 ± 9 nm. The carbonized control yeast cells (CCY) did not contain any particles on its surface. As(V) adsorption efficiency of CCY and CSY was deduced in batch mode by varying parameters like contact time, initial concentration, and pH. Desorption studies were also carried out by varying the pH. The experimental data were fitted onto Langmuir and D-R Isotherms and Lagergren and pseudo second order kinetic models. The CSY was more efficient in arsenate removal when compared to CCY.     

SoftUDC: a software-based data center for utility computing

Utility computing aims to aggregate server, network, and storage systems into a single, centrally managed pool of resources. SoftUDC, a virtual machine monitor, lets applications and administrative domains share physical resources while maintaining full functional isolation.     

CO2 laser processing for reducing core loss of cold-rolled grain-oriented silicon steel

Non-contact processing technique involving the use of CW and pulsed CO₂ laser irradiation has been used for reducing the core loss of cold-rolled grain-oriented silicon steel. Laser scribing perpendicular to the rolling direction resulted in a refinement of domain wall spacing which subsequently reduced the loss of silicon steel. It was found that laser irradiation was more effective in a specimen with higher magnetic induction (Hi-B) and the loss was reduced by more than 10% under optimum conditions of the laser irradiation and the scribing speed. Since laser processing is a non-contact technique, it can be easily applied to the production line of the silicon steel.     

Construction of a pseudolarynx after laryngectomy and radical neck dissection. A preliminary report

Oxytocin analogues which combine high oxytocic activities with negligible antidiuretic and pressor activities have been studied. [4-Threonine,7-glycine]oxytocin, [1-(L-2-hydroxy-3-mercaptopropionic acid),4-threonine,7-glycine]oxytocin, and [1-(L-2-hydroxy-3-mercaptopropionic acid)]oxytocin were found to possess the following specific biological activities respectively: rat uterotonic, 270 +/- 10, 337 +/- 23, 1542 +/- 0.4; rat antidiuretic, 0.002 +/- 0.0008, 0.048 +/- 0.005, 40.3 +/- 2.4. The results are analyzed from a conformation-activity viewpoint in a continued attempt to evaluate the scope and limitations of this approach in comparison to structure-activity studies.     

Low-Temperature Chemical Vapor Deposition Tungsten Carbide Coatings for Wear/Erosion Resistance

A new chemical vapor deposition (CVD) process has been developed to deposit hard coatings, containing tungsten carbide, at temperatures below 500°C. These coatings, which have been applied to both ferrous and nonferrous alloys, exhibit excellent resistance to wear and erosion. The coatings comprise a mixture of tungsten and the tungsten carbide, the latter being present as W₂C, W₂C + W₃C, or W₃C. The coatings' composition and properties can be controlled by varying the CVD process parameters. The unique lamellar, fine-grained microstructures of these coatings contribute to their good tribological properties.     

Room-temperature forming limit diagram and tensile behaviour up to 200° C of an AI-Ca-Zn superplastic alloy

The forming limit diagram and strain distribution under punch stretching at room temperature of an AI-Ca-Zn (superplastic) alloy have been evaluated. Tensile behaviour up to 200° C is reported. The fracture surfaces have been examined by scanning electron microscopy and the results are analysed to support the failure criterion proposed earlier by Marciniaket al.     

Chloridization beneficiation of ilmenite

Chloridization is a potential method of beneficiating ilmenite. Studies on beneficiation of ilmenite were carried out by using titanium chloride as the chloridizing agent in a laboratory scale fluidized bed reactor. Experiments were conducted on 1, 10, and 36 grams per batch scale, and the effect of the various rate determining steps on conversion was studied. Treated particles of ilmenite were examined for chemical composition, surface properties, and structural changes. The paper presents the experimental results on the chloridization treatment of natural and oxidized ilmenite.