148 research outputs found

    A Rapid Method of Crude Oil Analysis Using FT-IR Spectroscopy

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    This study determines the viability of the use of Fourier Transform Infrared (FTIR) spectroscopy as a substitute to traditional petroleum geochemical methods for crude oil characterisation. IR spectra of Crude oil sample containing a mixture of both degraded (sample 151) and non-degraded (sample 145) oils at different concentrations were determined. The IR fingerprints agree with results obtained from GC analysis. Partial least square regression analysis was used to predict saturates for omitted mixtures (10 and 80% 151) and also saturates of five other samples (i.e. 145, 149, 172, H1 and AL10) within acceptable error limits. It therefore, follows, that although some improvements might still need to be made, FTIR spectroscopy can indeed be a viable, simple, cheaper and faster technique of crude oil characterisation compared with the traditional fractionation methods.Keywords: FTIR-ATR spectroscopy; GC-MS; Partial least squares (PLSR). Rapid analysis

    Thermoplastic nanofluidic devices for biomedical applications

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    This review presents an overview of recent advancements in the fabrication, surface modification and applications of thermoplastic nanofluidic devices

    Preliminary Phytochemical Screening and Proximate Analyses of Leaf Extracts of Newbouldia laevis (Boundary Tree)

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    This work is designed to enrich the available scientific data on the phytochemistry and nutrient content of N. laevis leaves. The method of cold maceration was used in the extraction by serial exhaustive extraction method. The phytochemical screening of Newbouldia laevis was using through controlled experiment. Qualitative phytochemical screening and proximate analyses of Newbouldia laevis was studied using extracts of n-hexane, ethyl acetate, acetone and methanol which were obtained extract from powdered plant part. The extracts were subjected to qualitative phytochemical screening using standard procedure and the results shows that all the phytochemicals screened for were revealed in various leaf extracts. Alkaloids and flavonoids are present in all the extracts except ethyl acetate that did not show the presence of alkaloids. Only phlobatannins and tannins were absent in all the extract, steroid is present only in acetone. The proximate analysis revealed the nutritional composition of Newbouldia laevis to be 6.03% of moisture, 7.96% of ash, 9.81% of crude protein, 16.50% of fat, 33.40%. The diversity of phytochemical present suggested that N. laevis could serve as a source of drugs. Keywords: Newbouldia laevis, phytochemistry, Nutrient

    The Effect of Kelvin Effect on the Equilibrium Effective Radii and Hygroscopic Growth of Atmospheric Aerosols

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    In this paper we extracted microphysical properties of six types of atmospheric aerosols from Optical Properties of Aerosols and Clouds (OPAC) and numerically analyzed the analytical expressions for the changes in the equilibrium relative humidity (RH), effective radius, effective hygroscopic growth, the magnitudes and fractional changes in the effective radii  and the effective hygroscopic growth on the effects of surface tension (the Kelvin effect) on ambient atmospheric aerosols. The expressions were applied to two - one parameter models. We discovered from the analysis of the data extracted that, to the lowest order error, the change in the equilibrium RH, effective radii and effective hygroscopic growth depend on the compositions of the aerosols. From the two models used, we also discovered that the fractional changes in the ambient RH, effective radii and effective hygrosocopic growth, also depend on the aerosols compositions. Finally, we discovered that the magnitude of the Kelvin effect and its consequences on the atmospheric aerosols depend on the hygroscopicity of the aerosols. Keywords: Kelvin effect, effective radius, effective hygroscopic growth, atmospheric aerosols, ambient Relative Humidity

    Magnetic properties of X-Pt (X=Fe,Co,Ni) alloy systems

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    We have studied the electronic and magnetic properties of Fe-Pt, Co-Pt and Ni-Pt alloy systems in ordered and disordered phases. The influence of various exchange-correlation functionals on values of equilibrium lattice parameters and magnetic moments in ordered Fe-Pt, Co-Pt and Ni-Pt alloys have been studied using linearized muffin-tin orbital method. The electronic structure calculations for the disordered alloys have been carried out using augmented space recursion technique in the framework of tight binding linearized muffin-tin orbital method. The effect of short range order has also been studied in the disordered phase of these systems. The results show good agreements with available experimental values.Comment: 21 pages, 4 eps figures, accepted for publication in Journal of Physics Condensed Matte

    Avaliação de girassol e forrageiras tropicais perenes em cultivo consorciado.

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    O objetivo deste trabalho foi avaliar a produtividade de girassol e o rendimento forrageiro de capins Brachiaria brizantha cultivares Xaraés e Piatã e o Panicum maximum cultivar Massai em plantios consorciados e solteiros com girassol BRS 122. O ensaio foi implantado no Campo Experimental do Gorutuba, em Janaúba, região Norte de Minas Gerais. Para análise dos dados das forrageiras, foi utilizado um delineamento em blocos casualizados (DBC), no esquema de parcelas subdivididas, com três tratamentos e cinco repetições, tendo na parcela a forrageira e na subparcela a presença ou não do girassol. Para análise dos dados do girassol, foi utilizado um DBC com cinco tratamentos e cinco repetições,com as médias submetidas ao teste de Tukey a 5% de significância. Verificou-se a produção média de massa seca total de 5.916,6 kg/ha para as forrageiras em consórcio e de 13.534,7 kg/ha em plantio solteiro. As produções de grãos de girassol solteiro foram, em média, de 2.399,5 kg/ha e, em sistema de consórcio com as forrageiras, de 1.649,1 kg/ha. Os índices de Uso Eficiente da Terra (UET) foram de 1,12 para o consórcio com o Xaraés, 1,22 para o Piatã e 1,19 para o Massai. Nas condições deste ensaio, o consórcio com forrageiras perenes reduziu em 27% a produtividade média de grãos de girassol. Considerando os índices de UET e como alternativa para atender à demanda por biocombustíveis em regiões que apresentem vocação para pecuária, o plantio consorciado de girassol e capins pode ser recomendado aos produtores como forma de diversificação de produtos e de renda por meio da intensificação da produção vegetal em uma mesma área no período chuvoso.bitstream/CNPMS-2010/22653/1/Bol-19.pd

    An Ill Wind? Climate Change, Migration, and Health

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    Background: Climate change is projected to cause substantial increases in population movement in coming decades. Previous research has considered the likely causal influences and magnitude of such movements and the risks to national and international security. There has been little research on the consequences of climate-related migration and the health of people who move

    Leadership and Entrepreneurship: Preliminary Validation of Covenant Entrepreneurial Effectiveness Scale

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    Attaining and maintaining leadership in any field of human endeavour requires regular valid measurement and evaluation. The latter is the quest of Psychometrics. The core objective of this study, therefore, was to develop and attempt preliminary validation of the Covenant Entrepreneurial Effectiveness Scale [CEES], a monitoring device for entrepreneurs. The CEES was based on Schumpeter’s theory of Innovation in entrepreneurship and Leibenstein’s theory of entrepreneurship, combined with current observations of SMEs in a developing economy. The core research questions were: What are the internal consistency reliabilities of the CEES? What are the discriminant validity indices of the CEES? One hundred and ninety-four (194) small scale entrepreneurs were randomly sampled from Ado-Odo Ota local government area in Ogun State, Nigeria. There were 128 males and 66 females with age ranging from 20-65 years. The mean and standard deviation of their age were 38.05 and 8.56 respectively. The responses to the CEES were analysed with Cronbach alpha, Guttman Split-half and Spearman-Brown coefficients and independent student t-test. The results showed that the CEES has significant internal consistency reliability (0.755), splithalf reliability (0.742) and discriminant validities for entrepreneurs who were differentiated on Gender (t=2.75, p=0.007), Age (t=2.003, p=0.048), House (t=5.68, p=0.0) Car (5.89, p=0.0) and Annual Profit (t=3.432, p=0.001). It was recommended that the CEES be administered on SMEs in other parts of the globe to further ascertain its reliability and validity for regular monitoring and evaluation, to catalyse entrepreneurial leadership
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