Origin and thermal evolution of Mars

The thermal evolution of Mars is governed by subsolidus mantle convection beneath a thick lithosphere. Models of the interior evolution are developed by parameterizing mantle convective heat transport in terms of mantle viscosity, the superadiabatic temperature rise across the mantle, and mantle heat production. Geological, geophysical, and geochemical observations of the compositon and structure of the interior and of the timing of major events in Martian evolution are used to constrain the model computations. Such evolutionary events include global differentiation, atmospheric outgassing, and the formation of the hemispherical dichotomy and Tharsis. Numerical calculations of fully three-dimensional, spherical convection in a shell the size of the Martian mantle are performed to explore plausible patterns of Martian mantel convection and to relate convective features, such as plumes, to surface features, such as Tharsis. The results from the model calculations are presented

Effects of Dysprosium Oxide Nanoparticles on Escherichia coli

There is increasing interest in the study of dysprosium oxide nanoparticles (nDy2O3) for biomedical applications due to their fluorescence and paramagnetic properties. However, the fate of nDy2O3 and their effects on natural biological systems are a growing concern. This study assessed the toxicity of nDy2O3 on Escherichia coli for concentrations between 0.02 and 2 mg L−1, exposed to three concentrations of NaCl (8500, 850, and 85 mg L−1) and three glucose concentrations (35, 70, and 140 mg L−1). The ranges of these variables were selected to cover manufacturer recommendations of analytical methodologies for toxicity assessment, environmental and industrial nDy2O3 effluent concentrations, and metabolic activity. Two array-based toxicity techniques were used to evaluate the 27 combinations of conditions. Fluorescent dyes (Live/Dead) and respirometric assays were used to measure the undisturbed cell membrane (UCM) and remaining respiration percentage (RRP), respectively. Respirometric tests showed a higher toxic effect than Live/Dead test assays, indicating that metabolic processes are more affected than the physical structure of the cell by exposure to nDy2O3. After exposing the bacteria to concentrations of 2.0 mg L−1 uncoated nDy2O3 for 2 h at 85 mg L−1 NaCl and 140 mg L−1 glucose, the RRP and UCM decreased to 43% and 88%, respectively. Dysprosium ion (Dy+3) toxicity measurement suggested that Dy+3 was the main contributor to the overall toxicity

Solubility of Copper in Milk

The solubilities of copper in sweet whole raw milk held at a constant temperature for 30 minutes were determined for temperatures ranging from 20 degrees Centegrade to 100 degrees Centegrade. Copper sheets of known dimension were totally immersed and agitated in milk for 30 minutes at the specified temperature. Solubility values were determined by difference in weight of the copper sheets and also by determining colorimetrically with potassium ethyl xanthate the copper present in the ash of the milk. Solubilities per unit area increase with rise in temperature up to 80 degrees Centegrade

Impact of vertical high opening nets in Gujarat

Field trials ware conducted with an improved version of V. H- O. net of BOBP in Saurashtra waters by the Gujarat Fisheries Aquatic Sciences Research Station, Veraval. Both the fish catch and value improved. This center has been helping the fisherman to fabricate this modified version of net which Is popularly known as DISCO net to fisherman, The acceptance is total and within last two years 1600 modified V. H. Q. nets ware fabricated at Veraval alone. This paper gives the salient features of modified design and comparative statistic

Optimization of In-situ Electro-oxidation of Formaldehyde by the Response Surface Method

This investigation attempted to study electrochemical oxidation of formaldehyde at lower concentrations. Experiments were carried out in a batch electrochemical reactor using commercially available RuO2 coated titanium and SS as anode and cathode respectively and covering a wide range in operating conditions. Further, the statistical tool Response surface methodology by Box-Behnken design was used to examine the influence of individual parameters on electro-oxidation of formaldehyde, and the quadratic model for formaldehyde removal efficiency was derived. It was observed that the model predictions match well with experimental values with a R2 value of 0.999

Electro oxidation of Malachite Green and Modeling Using ANN

This study involves the electro-oxidation of malachite green, a triphenyl methane dye, extensively used in industries and aquaculture, and later banned in most developed countries because of its potential carcinogenicity, mutagenicity and teratogenicity in mammals. The study is conducted in a batch electro-chemical reactor using the catalytic anode (made of noble oxide coated, RuOx-TiOx, titanium expanded mesh) that mediates the oxidation of organic species by the formation of higher oxidation state oxides of the metal (e.g., RuO2 or IrO2). The operating variables are current density, electrolysis time and initial dye concentration. Complete removal of the dye has been reported by 41 minutes of treatment at a current density of 2.2 A dm–2 for the case of initial dye concentration of 200 mg L–1. The experimental data are modeled using back-propagation artificial neural network. The results were compared with experimental observations, and found that the model predictions adequately match experimental observations. Combination of the factors giving complete removal of the dye has also been commented