Effect of sintering temperature on electrical characteristics of ZnO-0.5 mol% V2O5-2 mol% MnO varistors

The effect of sintering temperature on the microstructure and the electrical response of liquid phase sintered ZnO-V2O5 varistor ceramics were analyzed using A.C impedance spectroscopy on samples prepared via conventional solid route. The impedance spectra were analyzed with the help of the model equivalent circuit at high frequencies and another at low frequencies, involving both resistor and constant phase element (CPE). The results indicate a significant contribution of grain boundary resistance to the non-ohmic characteristic of the studied materials.

The products were characterized regarding phase with X-ray diffraction, microstructures with SEM. Electrical characteristics were studied with impedance analysis and current-voltage characterization. In the present investigations studies, have been made on the effect of sintering temperatures (850°C, 900°C, and 950°C) on the microstructure and electrical properties of MnO and MgO doped ZnO-0.5 mol% V2O5 varistor system. The phase composition of samples consists mainly ZnO grains, while Zn2VO4 is the secondary phases. Better varistor performance has been achieved for the samples sintered at 950°C with nonlinear coefficient α=16, breakdown voltage 2513.3 V/mm and leakage current is JL=7.7 × 10-5 A/cm2. SEM analysis of morphology shows that the grain growth increases with increase in sintering temperature.

Usefulness of a nutraceutical diet to improve qol and drugs use in a dog affected by a mast cell tumor: a case report

On October 2014, a 10-years-old male neutered boxer presented to the Wiligelmo Veterinary Clinic of Modena (Italy) for the sudden onset of 3 cutaneous nodular lesions. The first, a large movable lesion, was clearly visible on the dorsal face of the second finger of the right forepaw, which was linked to the paw by means of a tight peduncle. Intriguingly the skin of this lesion resulted intact, neither alopecic nor with signs of dermatitis. The second lesion, on right side of the tail, was subcutaneous, poorly movable and with a blackish, alopecic but not ulcerated skin. The same features characterized the third lesion on the left dorsal side of the gluteus region.

Continuous system of freeze concentration of sucrose solutions: Process parameters and energy consumption

Continuous processes to freeze-concentrate aqueous solutions of sucrose are proposed that integrates the falling film technique, fractionated thawing, and block freeze-concentration. Data reported in our previous studies were used to study the two first techniques. Block freeze concentration tests were performed to recover the solutes present in the diluted fractions.

Starting with a solution with 5% w/w solids, a concentrated liquid with 20% w/w solids and an effluent with 0.3% w/w solutes were obtained. The falling film freeze technique effectively concentrated the sucrose solution. Fractionated thawing increased the recovery of solutes retained in the ice from 39 to 50%. Block freeze concentration increased solute recovery to 95%. A concentration index of 4.0 and a concentration efficiency of 98.5% were obtained by integrating the techniques. Under the assumptions considered in this work, theoretically the energy consumption of the process can reach a value of 10.3 kWh/1000 kg of ice removed, which represents a saving of 30% compared to the energy consumption of the most efficient evaporation systems.

Practicality and importance of selected endothelial dysfunction measurement techniques ‐ Review

The measurement of endothelial dysfunction (ED) has importance in that it indicates the presence of coronary artery disease in addition to acting as a predictor of future adverse events. Various tools, methods, and metrics exist that can provide an indicator of endothelial dysfunction. Given the significance of ED, it is of utmost importance to find a measurement technique that is reliable, while defining a metric providing a framework for an overall system that is practical, accurate, and repeatable. Success would provide a tool for early detection of cardiovascular disease not only moving patients that are currently classified as asymptomatic to symptomatic but also providing a method to monitor efficacy of treatments.

Molecular Identification of Rotylenchulus Reniformis (Nematoda) By Using Its Region of Rdna

Reniform nematode (Rotylenchulus reniformis) is widely distributed in all cotton (Gossypium spp.) grown regions of India. In Reniform nemotode infection, the growth of cotton roots and shoots was reduced at level of more than 8 and 1 nematode per g soil, respectively. DNA-based Molecular identi?cation of Plant parasitic nematode species has been determined by Internal Transcribed spacer (ITS) gene with PCR Techniques. 

The ribosomal DNA (rDNA) is a novel genetic marker and it is a multi-gene family consisting of many copies (100-500 in animals) of genes encoding for three ribosomal components 28S, 5.8S and 18S. Phylogeny is the history of organism lineage as they change through time. It implies that different species arise from previous forms via decent and that all organisms from the smallest microbes to the largest plants and vertebrates were connected by the passage by genes along the branches of the phylogenetic tree that links all the life form. 

Effect of floor cleaners on oxygen consumption and respiratory rate in carassius auratus

Pollution of the water bodies will create physiological stress on the aquatic fauna. Among various forms of pollution in water bodies, detergent pollution has an immediate and detrimental effect. The floor cleaners are household chemical cleaning compounds required in wide range for diverse purposes. In some rivers the concentrations of cleaning products is quite high. The major components of cleaning products such as Surfactants make adverse effects on the aquatic life at very low levels of exposure. Effect of floor cleaners on the consumption of dissolved oxygen by Carassius auratus were determined by using Winkler’s method. The floor cleaners used were Lizol, dettol and lemon grass oil. This study demonstrated that dissolved oxygen consumption in Carassius auratus increases in the presence of floor cleaners. 

Investigation of the optimized dextran-degrading enzyme conditions on the decomposition of different molecular weights of pure dextran using response surface methodology

The elimination of various molecular weights of contaminated dextran in sugar processing is quite complicated, especially using enzymatic decomposition. Many factors including enzyme concentration, retention time, pH, temperature, and sucrose concentration affect enzyme hydrolysis. 

The optimizing conditions of various molecular weights of dextran removal were investigated using response surface methodology. The optimum hydrolyzed conditions of 1,500? G/mL of all molecular weights of pure dextran from the one-factor-at-a-time (OFAT) experiments were: dextranase (Amano Enzyme Inc., Japan) at 5-15 ppmtotal soluble solids for 5-15 min at 50-65? C with pH 4.5-6.5 and sucroseconcentration at 15-25%. The results from the OFAT experiments used a Box-Benhken experimental design with four factors and three levels that achieved fit models that predicted the dextran removal under different conditions of various molecular weights of pure dextran.