Archives-September 2011

An aqueous extract of Piper Nigrum. L (PNL) has been prepared as a corrosion inhibitor to control the rate of corrosion. This compound has been investigated as corrosion inhibitor at room temperature for preventing mild steel corrosion in Citric acid medium at different molar concentration by weight loss method and by adsorption isotherm. The result showed that the corrosion inhibition efficiency of this aqueous extract of PNL was found to vary with different molar acid concentration. Also, it was found that the corrosion inhibition behavior of PNL is greater in 1M Citric acid than 2M Citric acid due to aggressive nature of acid. So PNL can be used as a good inhibitor for preventing mild steel material. The surface analysis study confirms the corrosion of the mild steel and its inhibition by the inhibitor Piper Nigrum.L.

In the present study, the mosquito density of three selected sites of Dindigul district viz., Sempatti, Chinnalapatti and J.K.Patti was surveyed. The results of the study indicate the presence of 10 species of mosquitoes which are grouped under four genera namely Aedes, Anopheles, Armigeres and Culex. The numbers of mosquitoes collected belonging to various species were low with an exception of Culex quinquefasciatus. The diversity measures (Shannon’s and Simpson’s) shows slight variation among the three selected sites studied. The Shannon’s index for Chinnalapatti is slightly higher (1.883) when compared to Sempatti and J.K.Patti (1.804 and 1.804). The Simpson’s index for Chinnalapatti is slightly higher (0.7994) when compared to Sempatti and J.K.Patti (0.7677 and 0.7579). In the study period, the maximum density of the mosquito population noted in the month of July and October. The minimum density of mosquito population obtained in the month of September.

Impulse noise is the major factor that affects the image during signal acquisition and transmission. Here an efficient simple edge preserving denoising technique is used to remove the impulse noise. To avoid the possible misdetection this technique does not affect the noise free pixel. It uses different directional edges to preserve the edge information. The experimental result shows excellent performances in terms of quantitative evaluation and visual quality. The design cost is also low because it needs only two line memory buffer and less computational complexity.

Image segmentation is the process of dividing images according to its characteristics like color and objects present in the images. The general segmentation problem involves the partitioning of a given image into a number of homogeneous segments, such that the union of any two neighbouring segments yields a heterogeneous segment. This can further be used for surgical planning, to avoid open surgery. The techniques used are namely gray scaling, edge detection, contrast enhancement, watershed segmentation and finally marking the region of interest. Comparision of different edge detection techniques based on peak signal to noise ratio and root mean square error is performed. Finally Watershed segmentation uses the intensity as a parameter to segment the whole image data set. The results show that Watershed Segmentation can successfully segment a tumor. All the mentioned modules and techniques have been implemented in MATLAB environment for the brain tumor detection using input MR images and the part of modules like edge detection, thresholding and high pass filter are also implemented in FPGA using Verilog in Xilinx environment, the advantage being speed enhancement and re-configurability.

Liposomes are an important colloidal carrier system for controlled drug delivery. However some highly hydrophilic small molecules are difficult to entrap into liposomes and store stably, resulting in poor encapsulation efficiency and fast leakage. In present study, Docetaxel was used as a model drug that was loaded into chitosan nanoparticles and the encapsulated into liposomes by ethanol injection method (EIM). The vesicular systems were characterized for particle size, zeta potential, Transmission Electron Microscopy (TEM) and evaluated for encapsulation efficiency and in vitro release. The Lip-Np was composed of Hydrogenated Soya phosphatidylcholine, Cholesterol, EPG and Chitosan with average diameter of 207.8nm and zeta potential of +21.7mv. The entrapment efficiency was above 90% in Chitosan coated (Lip-Np). The release rate of docetaxel from Chitosan coated Lip-Np was more than 90% after 72h.

The diversity of Noctuid moths of the Nilgiri, an important International Biosphere in the Western Ghats of South India, was studied in four different places namely Coonoor, Doddabedda, Kothagiri and Ooty in the Nilgiri Biosphere and Kodaikanal. The data obtained between January 2009 (140 species) and December 2010 revealed the presence of 154 species of Noctuid moths classified under 85 genera and 23 subfamilies. Total number of taxa and individuals of Noctuid moths were found maximum in the year 2010.

Biomass is a renewable energy source refers to living and recently dead biological materials that can reduce green house effect and clean surroundings. To estimate tree biomass individually from imagery, it is necessary to clarify the relationship between attributes of stand structure obtained by field measurement and remote sensing image.This study was carried out to estimate tree biomass in Universiti Putra Malaysia (UPM) campus. Five plots were established (40 m x 40 m) and all trees with diameters at breast high (dbh) more than 30 cm , tree height and canopy size were measured. Each trees biomass were calculated by non-destructive method. Results show that tree volume is ranged from 1.75 m3 to 24.73 m3, wood density is ranged from 0.99 t/m3 to 14.10 t/m3. The overall wood densities for five plots (30 trees) are 23.35 t/m3. Meanwhile the biomass estimated is 7,644 t/ha. Study demonstrate strong correlations (p < 0.05) between field measurement and IKONOS tree canopy estimates (r2 = 0.95). The results obtained from the analysis are encouraging especially canopy measurement where it can be incorporated to the existing mensuration models. Estimating tree biomass through satellite images are recommended because remote sensing through image processing has potential to estimate biomass in large area.

Development of molecular markers for various desirable traits related to disease resistance, drought tolerance, compact canopy, higher yield, etc hold great potential for crop improvement of Casuarina equisetifolia L. This work focuses on the analysis of genetic relationship between 24 first generation colones of C. equisetifolia. Total genomic DNA was isolated by CTAB method and amplified with random oligonucleotide primers (Ten arbitrary 10-mer primers from Oberon Technologies Primer, USA) using PCR. The polymorphic bands were detected on agarose gels. Each random primer used in this study produced distinct bands. These were used for the final analysis. Six primers (OPM-05, OPM-13, OPB-18, OPE-06, OPE-07 and OPE-08) yielded 39 scorable bands. These bands were then constructed using the RAPD distance v1.04 package. Following this, SHAN method in NTSYSpc v2.02 was used to generate a pair wise distance matrix between various clones of C. equisetifolia. The highest genetic similarity co-efficient value (0.91) was observed between clones APSKLM-25 and APVSP-14 while the lowest co-efficient value (0.04) was seen between clones APKKD-11 and APKKD-9. The RAPD study was helpful to establish clonal identify.

In present study oilseeds were collected from different parts of Marathwada region and screened on different media for the incidence of different fungal species. Thirty fungal species were found to be associated with oilseeds. A study was also conducted to determine the antifungal activity of essential oils and gums of some medicinal plants against storage fungi. Eucalyptus oil and gum of Terminalia arjuna, Acacia Arabica and Butea monosperma inhibited the growth of storage fungi.

This research deals with Low Cycle Fatigue (LCF) tests for three types of polymers, polyvinylchloride (PVC), polyoxymethy (POM), and polyamide (PA). The tensile test results showed that advantage cannot be taken from u y ratio and strain hardening coefficient (n) to estimate polymers behaviour under LCF test. There was a similarity in polymers behaviour with metals in the aspect of total strain, elastic strain and plastic strain curves with total cyclic number (2N). Fatigue strength exponent (b) and fatigue ductility exponent (c) for the polymers recorded values within metals limits. POM polymer showed less softening and greater transition life (NT). PA polymer exhibits sensitivity to external stress concentration in terms of reduction of transition life (NT). Softening behaviour of PA polymer increases with lower value of the notch radius.