Archives-September 2013

Void fraction measurements are made by the gamma radiation method in crude oil-water two phase flow. To measure the void fraction, the required gamma-ray source and the strength of the source is experimentally found for oil-water two phase flow using Cs137.This is achieved by the empty small plastic tubes were used for simulating the void fraction through the mixture. The obtained results show that, the void fraction value increase with the source count rate by the NaI (Tl) counter.

Plant extracts are excessively used as corrosion inhibitors. Plant extracts contain a variety of organic compounds such as alkaloids, flavonoids, tannins, cellulose and polycyclic compounds. The compounds with hetero atoms-N, O, S, P coordinate with (corroding) metal atom or ion consequently forming a protective layer on the metal surface, that prevents corrosion. These serve as cheaper, readily available, renewable and environmentally benign alternatives to costly and hazardous corrosion inhibitors .This study reports screening of phytoconstituents and also reports the influence of the addition of Pongamia pinnata (L.) Pierre leaves extract on the corrosion inhibition of mild steel in 2.0 M H2SO4 solution using the Mylius thermometric technique. Results of the study revealed that Pongamia pinnata (L.) Pierre. leaves act as corrosion inhibitor for mild steel in the acidic medium. The addition of 0.1 M potassium chloride, potassium bromide and potassium iodide to the inhibitor enhanced the inhibition efficiency. The order of reactivity of halide ions is of the order KI > KBr > KCl. The inhibition efficiency increased 58 % to 78 % at a concentration of 0.1 M KI and 5.0 % of inhibitor concentration. The values of adsorption of Pongamia pinnata (L.) Pierre leaves extract onto the mild steel surface show that the process is spontaneous.

Pen is a product, which has used by each and every person. There are various brands of pen in the market of different types of price, colour, design, grip, attractive ink, attractive body, etc. So the pen market is full of competition where the consumer possesses vast variety of choice to select his/her brand which depends on their perception. It is very difficult to find the consumer perception about pen, even though the present study tried to find how the consumer purchase and prefer the brand, what factors influence the purchase of preferred brand of pen? The technique of data collection is through questionnaire. The sampling technique used for this project is convenience sampling. A closed ended with suitable scaling, open ended questions and discussion with the respondents was used to collect the required primary data. In this survey primary data were collected through interview schedule and mall intercept. Statistical tool used for analysing the data are cross- tabulation, Chi-Square- Goodness of Fit, Friedman Test.

We have synthesis manganese sulfide nano-crystalline (n-MnS) powder using manganese acetate and thiourea, trisodium citrate, from chemical route at different pH. The formation of MnS has been confirmed with help of infrared (IR) spectroscopy by observing bands corresponding to the multi phonon absorption. We have also observed the IR bands at 1403 and 1560 cm-1 due to symmetric and asymmetric stretching of COO of the capped sodium citrate at MnS nano-crystalline particles. The Size of crystal is determined as 3-5 nm with the help of X-ray diffraction. We also deposited the thin film of MnS on glass substrate from the solution using self- aggregation approach. The film thickness is measured as 366 nm with profile meter. The optical band gap is calculated as 3.1-3.5 eV. Its value is found to depend on pH. We also measured dark and photo- conductivity at different temperatures.

The next paper shows the successful case of an strategic management model based in competences, used by the organization AIESEC to be implemented in small and medium enterprises located in Guadalajara’s metropolitan zone, all this, with the main purpose of improving in those areas where the firm has the opportunity to grow and become more competitive.

Over the last three decades of the 20th century, gross domestic product per capita, exponential growth in mobile technology and population growth were the main drivers of increases in global warming and climate change. Industrial revolution and electronics, information and communication technology products have altered the landscape of modern society in countless ways, in office, at home and on mobility. However, they have created and added a new source of heat generation and emission into environment due to consumer electronics products. In spite of recent studies indicating possible threats to global climate, there is no long term data available on the amount of heat generated, emitted and dissipated into environment by cell phones. The aim of this research work is to experimentally measure the heat generated by cell phones during on(sleep/Idle) mode, Rx and Tx modes. The experiments were conducted using specially fabricated four decimal digit temperature measurement test instrument. Population and cell phones projections for India, China, USA and the whole world were also included in this research work for 2050. An attempt is made to indicate amount of heat generated, emitted and dissipated into environment by India, China, USA and entire world by cellular mobiles at present and projections for 2050.

Experiments were conducted to assess the relatedness of different subfamilies of Erebidae family using RAPD-PCR technique. The genomic DNA of thirteen different species of Erebidae moths belonging to different subfamilies of Erebinae, Calpinae and Hypocalinae were subjected to RAPD-PCR analysis. A total of 300 bands were scored with five RAPD primers, of which 291 were polymorphic bands while 9 were monomorphic bands; the percentage of polymorphism was 97%. Dendrogram revealed that the thirteen species were grouped into three major clusters and four subclusters.

A variable frequency and variable phase function generator with three outputs of (1) reference f_O (2) lead phase f_O + Æ₁ and (3) lag  phase f_O - Æ₂, is described in this paper. The leading phase difference Æ₁ is continuously adjustable over 0 to 180^o by an input control voltage V_C1 and the lagging phase difference Æ₂ is also continuously adjustable over 0 to -180^o by an another input control voltage V_C2, independent of frequency of operation of the function generator which can be set by a third control input dc voltage –V_I

The in vitro antibacterial activity of flavonoid and alkaloid extracts of various plant parts of V. negundo and A. paniculata was investigated using Disc Diffusion Assay against four Gram negative (E. aerogens, R. planticola, A. tumefaciens and K. pneumoniae) and one Gram positive bacteria (B. subtilis). Minimum inhibitory concentration of the extracts was evaluated by micro broth dilution method, while minimum bactericidal concentrations were determined by sub culturing the relevant samples. The extracts exhibited antimicrobial activities with zones of inhibition ranging from 9 to 23.5 mm. A. tumefaciens was found to be most susceptible organism in the investigation against which all the extracts showed positive response. Stem free flavonoid extract of V. negundo and stem bound flavonoid extract of A. paniculata was recorded as most active extract as it showed significant zone of inhibition against all the tested pathogens. The range of MIC and MBC was recorded 1.25-0.039mg/ml. Results of the present study reveal that extracts of both the selected plants are showing great antimicrobial potential against tested pathogen, and may be exploited for future antibacterial drugs.

Geophysical investigations are increasingly applied to urban planning development for mapping and monitoring. Vertical electric sounding method and seismic refraction technique were used in Imam Khomeini International Airport (IKIA) Iran, in an attempt to define the subsurface structure, variation in thickness and strength of layers and also, determine the earthquake prone zones in the area. Distribution of electrical resistivity indicated that the study area can be divided into two parts of northern-southern or northeast-southwest. The fine grain silt, clay, marble and chalk deposits with low resistivity are created thick layers in southern and southwest parts of area. In depths 30, 50, 100 and 150 m we are faced to change in soil materials, in the other word change in layer composition mainly occurred at these depths. Also, the real and vast aquifer cannot be considered for this site and just local small mounding of groundwater in some positions such as northern part of area, in deep old alluvial deposits can be guessed. It seems that fault or discontinuity is passed from northwest to the southeast of the study area and is caused the change in geology and sedimentary conditions. According to Iranian Seismic Code (Standard 2800), most of the land around the airport are in class 2 and 3 and the future construction in this region will be required to comply with the standard design principles.