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Mathematical Modeling of Optimal Position of Chips on Printed Circuit Board (PCB)
Get PDFThere has been a rapid development of electronic devices and competition among electronic companies to produce smaller and lighter devices with high performance, reliability, and multi-functionality. This results in the adjustment of an increasing number of electronic components called chips. The demand for small shape and size of the devices requires microanalysis in this field. To adjust the maximum number of chips, the space among them should be minimized. However, the problem arises as each of the chips can generate a significant amount of heat, which can degrade the performance of the device, and some chips could be completely damaged due to high temperature. Each component has its own maximum tolerable temperature, and if this temperature exceeds, the component may not function properly or could be damaged completely. Thus, thermal management is an important issue for both electronic components and the board (Printed Circuit Board) where they will be placed. This paper presents the heat distribution on the module, and based on this heat distribution, a modified gradient algorithm has been used to determine the optimal position of the chips on the board. Numerical computations have been performed for a 1D space module, and numerical results are presented graphically for the 1D space module by considering specific configurations and physical properties of chips
Comparative Analysis of Solasodine from in vitro and in vivo Cultures of Solanum nigrum Linn.
Get PDFAn efficient protocol was devised for rapid callus induction of Solanum nigrum Linn. from young leaves. MS medium supplemented with different concentrations IAA (1-3 mg/l) with BAP (0.5 mg/l) and NAA (1-3 mg/l) with BAP (0.5 mg/l) for callus initiation. The growth of the calli derived from leaves increased with time of incubation and remained almost constant after 30 days. For solasodine estimation, the field grown plant part of young leaves and in vitro callus (0.5 g each) were weighed and extracted thrice with methanol and subjected to HPLC. The solasodine content of field grown leaves extracts was 0.0798 mg g-1 whereas the solasodine content in the in vitro callus extracts were 0.142 mg g-1 in 2.5 mgL-1 IAA + 0.5 mgL-1 BAP, followed by 0.1162 mg g-1 in 2 mgL-1 NAA + 0.5 mgL-1 BAP
Partial Purification and Characterization of Bacillus pumilus Xylanase from Soil Source
Get PDFHydrolysis of xylan, the chief type of hemicellulose, is achieved by endo-1,4-β-xylanase and β-xylosidase among other such enzyme complexes. These enzymes are mainly produced by fungi, bacteria, etc. Xylanase finds applications in animal feed, manufacture of bread, beverages, textiles, bleaching cellulose pulp, ethanol, and xylitol production. Xylanase depolymerizes xylan molecules into xylose units, a primary carbon source for bacteria and fungi. In this study, we obtained a bacterial isolate exhibiting good extracellular xylanase activity by screening several soil samples. The bacterium identified was Bacillus pumilus. The isolate produced xylanase demonstrating maximal activity at 35°C and at pH 7.0. Crude extract fractionated by ammonium sulfate precipitation had a specific activity of 0.69 µM min-1 mg-1. Enzyme kinetics and properties were studied by DNS assay method. Xylanase had Km of 4.0 mg ml-1 and Vmax of 0.068 × 10-4 mM min-1 mg-1. Molecular weight of xylanase was 19 kDa as determined on SDS PAGE. The enzyme was partially purified to a fold of 3.79 and a yield of 66%, suggesting the method with fine-tuning could be suitable for scale-up process
Antibacterial Property of Different Medicinal Plants: Ocimum sanctum, Cinnamomum zeylanicum, Xanthoxylum armatum and Origanum majorana
Get PDFCountries like Nepal and India have been using crude plants as medicine since Vedic period. A major part of the total population in developing countries still uses traditional folk medicine obtained from plant resources (Farnsworth 1994). With an estimation of WHO that as many as 80% of worlds population living in rural areas rely on herbal traditional medicines as their primary health care, the study on properties and uses of medicinal plants are getting growing interests. In recent years this interest to evaluate plants possessing antibacterial activity for various diseases is growing (Clark and Hufford, 1993). Based on local use of common diseases and Ethnobotanical knowledge, an attempt has been made to assess the antibacterial properties of selected medicinal plants.VIZ. Ocimum sanctum (Tulsi), Origanum majorana (Ram Tulsi), Cinnamomum zeylanicum (Dalchini), and Xanthoxylum armatum (Timur), for potential antibacterial activity against 10 medically important bacterial strains, namely Bacillus subtilis, Bacillus cereus, Bacillus thuringiensis, Staphylococcus aureus, Pseudomonas spp, Proteus spp, Salmonella Typhi, Escherichia coli, Shigella dysentriae, Klebsiella pneumoniae. The antibacterial activity of ethanol extracts was determined by agar well diffusion method. The plant extracts were more active against Gram-positive bacteria than against Gram-negative bacteria. The most susceptible bacteria were B. subtilis, followed by S. aureus, while the most resistant bacteria were E.coli, followed by Shigella dysenteriae, Klebsiella pneumoniae and Salmonella typhi. From the screening experiment, Origanum majorana showed the best antibacterial activity; hence this plant can be further subjected to isolation of the therapeutic antimicrobials and pharmacological evaluation. The largest zone of inhibition was obtained with Xanthoxylum armatum against Bacillus subtilis (23mm) and the minimum bactericidal concentration (MBC) value of 2.5 mg/l was obtained
Effect of UV-Treatment on the Wettability of Polycarbonate
Get PDFThis paper presents the results of the effect of ultra-violet (UV) radiation treatment on the wettability of polycarbonate surfaces. Two wavelengths of UV radiation, namely 254 nm and 365 nm, were employed in the study. The impact of treatment duration on sample wettability was assessed by measuring contact angles with two different test liquids. The investigation revealed that treatment with shorter wavelength UV radiation resulted in higher wettability compared to treatment with longer wavelength radiation. Furthermore, the total surface free energy of the sample, calculated using a two-liquid model, showed an increase of approximately 7 mJ/m² from the original value of 30 mJ/m² after 25 minutes of treatment with UV radiation at 254 nm
Recycling of Spent Oyster Mushroom Substrate to Recover Additional Value
Get PDFAfter the cultivation of Pleurotus eous, possibilities of reutilization of spent mushroom substrate (SMS) was carried out in form of ingredient for the cultivation of three oyster species, viz., Pleurotus sajor-caju Strain- Malasia, Pleurotus florida Strain-P1 and Pleurotus flabellatus and as fertilizer for growing Spinacea oleracea. As an ingredient, it was mixed properly with fresh wheat straw @ 10,15 and 25 % where 25% SMS supplemented sets showed significant yield and biological efficiency of mushrooms than control. It was recorded 345 gm, 69%; 565 gm, 113% and 525 gm, 105% for Pleurotus sajor-caju Strain- Malasia, Pleurotus florida Strain-P1 and Pleurotus flabellatus respectively. For use as a fertilizer, SMS was infested in to the soil at three different proportions (1, 3 and 5%). It showed quick seed emergence and higher yield than pure soil, however, the yield was recorded significant only in 5% SMS containing sets
Influence of Sewerage Network on Groundwater, Using Radiogenic Isotope Tritium
Get PDFRadiogenic isotope tritium (3H) together with chemical compositions of water was used to discriminate ground water age and recharge areas and probable recharge processes respectively in four valleys of Bangalore. Forty seven (47) grounds and twenty (20) surface water samples were collected to assess the TDS, EC, Salinity and 3H. The groundwater available in four valleys contained high 3H (>1TU), suggesting recent recharge and belong to 100% modern age. Modern recharge in the aquifer is influenced by the sewerage network and as a consequence groundwater contains higher TDS, EC, salinity and 3H
Molecular Confirmation of the Presence of Coliforms in Drinking Water Using Polymerase Chain Reaction
Get PDFColiform bacteria include organisms like Escherichia coli, Enterobacter, Klebsiella, and Citrobacter. They are gram-negative, facultative anaerobic, non-sporulating, and lactose-fermenting organisms. E. coli is used as the indicator organism for detection of fecal contamination of water. Conventional methods for the detection of these Coliforms in water include microbial culture assays in lactose-containing media and enzyme-based assays for the detection of β-galactosidase using chromogenic substrates like ortho-nitrophenyl-β-D-galactopyranoside. These methods are cumbersome with limited specificity. DNA-based molecular techniques like Polymerase Chain Reaction (PCR) are recommended since they are highly specific. In this paper, we report the use of PCR for the amplification of the Lac Z (β-galactosidase encoding) gene to confirm the isolation of Coliform bacteria from drinking water samples. The method could be an effective epidemiological tool to pinpoint the source and contain outbreaks of waterborne disease episodes
Study on Relative Abundance and Distribution of Tiger Prey Base (Ungulates) in Khata Corridor, Bardia National Park
Get PDFThe study provides information on distribution, abundance of wild ungulates and their link to habitat characteristics at a landscape level conservation. Khata Corridor is an important component of Terai Arc Landscape. It is about 9 km long and connects Bardia National Park, Nepal with Katarniaghat Wildlife Sanctuary, India. Relative abundance and distribution of Tiger prey base species (wild ungulates) was studied from mid April to mid June 2008 at Khata Corridor. A total of 127 transects (1 transect=625m, distance between adjacent transect=100m, distance between two parallel transect=100m) containing 2700 circular plots of 10m2 were laid and sampled following Smith et al (1999). A total of 2043 wild ungulates pellets were counted within the sampled area with a mean pellet group abundance of 0.75 pellets per plot. Mean pellet group abundance of Spotted deer, Wild boar, Monkey, Hog deer, Barking deer and Blue bull were 0.63, 0.06, 0.05, 0.02, 0.00 and 0.00 per plot respectively. Species wise ungulate abundance showed that Barking deer was highest in Low Density Mixed Forest, Spotted deer in Grassland, Hog deer in both Grassland and Low Density Mixed Forest, Blue bull only in Low Density Mixed Forest, Monkey in Riverine Forest and Wooded Grassland, and Wild boar in Wooded Grassland. Distribution pattern of wild ungulate species was of Clumped type (S2/a=93.10). Out of four habitat types, flood plains with riverine forest and grasslands were considered important habitats. Khata has been experiencing different levels of degradation also has tremendous conservation potential to ensure long term viability of large mammals (eg. Tigers) if restored and integrated into landscape level conservation plans