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1.
The chemical method has proved to be the most effective mitigating method of wax deposition in petroleum system as it deals with the root cause of wax formation. Most of the commercial chemicals in the industry are very expensive and toxic. This paper aims the use of biodiesel based additives for improving the rheological behavior and pour points of waxy crude from Nigeria field. The biodiesels derived additives gave better performance than the commercial chemical and the seed oils as greatly improvement in rheology and pour point values of the waxy crude were observed  相似文献   
2.
Noninvasive Assessment of Human Gastric Motor Function   总被引:23,自引:0,他引:23  
A noninvasive technique to monitor gastric electrical activity (GEA) and mechanical activity as an aid in assessing gastric motor function is presented. The GEA is measured with ordinary ECG electrodes located on the torso in the region above the stomach. The mechanical activity is recorded through an electrical impedance monitoring device. A study of a mathematical model of the electrically active antral part of the stomach in the body revealed that the waveform of the extracorporeally measured signals can be related to the direction of propagation of the GEA. This feature was confirmed experimentally.  相似文献   
3.
This study reports on an exploratory survey conducted to investigate the use of social media technologies for sharing information. This paper explores the issue of credibility of the information shared in the context of computer-mediated communication. Four categories of information were explored: sensitive, sensational, political and casual information, across five popular social media technologies: social networking sites, micro-blogging sites, wikis, online forums, and online blogs. One hundred and fourteen active users of social media technologies participated in the study. The exploratory analysis conducted in this study revealed that information producers use different cues to indicate credibility of the information they share on different social media sites. Organizations can leverage findings from this study to improve targeted engagement with their customers. The operationalization of how information credibility is codified by information producers contributes to knowledge in social media research.  相似文献   
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We demonstrate that the Ugi reaction enables chemoselective derivatization of biological amines, carboxylic acids, aldehydes, or ketones with a chromophore under one set of reaction conditions, even in the presence of water. Derivatization of neurotransmitters, hormones, disease biomarkers and other metabolites bodes well for systems biology and diagnostic medicine.  相似文献   
6.
The effect of partial substitution of sugar with liquid honey on the pasting properties of cooked dough made from cassava-wheat composite (10:90) flour as well as the sensory preference and shelf stability of its bread was investigated. Sucrose (S) in the bread recipe formulation was substituted with honey (H) at levels 0, 10, 20, 30, 40 and 50%, respectively to give 6 treatments, namely 0H:100S, 10H:90S, 20H:80S, 30H:70S, 40H:60S and 50H:50S. Amylograph pasting properties of the dried crumbs were determined using standard analytical procedures. Fresh bread samples were subjected to sensory evaluation and fungal count during storage (6 days). Peak, final and setback viscosities of bread crumb decreased (32.29 to 25.33, 58.54 to 43.00 and 30.96 to 23.66 RVU), respectively as the level of honey inclusion increased. Honey substitution levels used did not significantly (p > 0.05) affect aroma and texture of the bread samples but composite bread with 20% level of honey substitution was most preferred in terms of colour while composite bread with 30% level of honey substitution was most acceptable in terms of taste and overall acceptability. Fungal count in stored honey-cassava-wheat bread varied significantly (p < 0.05) from 0.6 to 4.0 × 102, 1.0 to 6.9 × 102, 2.2 to 57.0 × 102, 32.0 to 135.7 × 102, 34.0 to 140.0 × 102 and 42.0 to 159.3 × 102) cfu/ml from day 1 to day 6, respectively. From the study, it was concluded that substitution of sugar with honey in dough formulations significantly (p < 0.05) affects dough pasting properties, improves acceptability of the composite bread and reduces staling rate.  相似文献   
7.
In this paper, experimental and numerical studies are made to investigate local thermal equilibrium in a microwave plasma torch at atmospheric pressure for hydrogen and carbon black production from methane dissociation. The microwave induced plasma can be operated up to 2 kW power at 2.45 GHz frequency. Methane is dissociated in argon, air or nitrogen plasma and optical emission spectroscopy is used to characterize the plasma. C2, CN and OH ro-vibrational bands are used for rotational and vibrational temperature estimation while stark broadening of H-line is used for electron temperature calculation. Temperatures are determined at varying operating parameters of microwave power, axial gas flow rate, and methane flow rate. The rotational (heavy particle), vibrational, and electron temperatures are found to be equal to 5000 ± 500 K. The plasma is thus at local thermodynamic equilibrium.  相似文献   
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In this paper, we investigate the extent to which economic, human development endowment, political, and population conditions influence information and communication technology (ICT) capacity in African nations using ordinary least squares. We use five variables to measure ICT capacity: ICT expenditure as a percent of GDP (ICTE), ICT expenditure per capita in US dollars (ICTEP), investment in telecoms with private participation (INVTE), Internet users per 100 people (INTUS), and mobile phone subscribers per 1000 people (MOBPS). Unlike ICT adoption and diffusion that focuses on the use of ICT, ICT capacity measures public and private investments in ICT and the use of ICT. The results indicate that ICT capacity of a nation increases with increased (high) corruption index. Further, ICT investment by the private sector depends mainly on human development factors and is not influenced by the perceptions of corruption about a nation. We present theoretical and practical implications of the findings for developing nations in general and African nations in particular.  相似文献   
10.
The impact of oil price shocks on the macroeconomy has received a great deal of attention since the 1970 s. Initially, many empirical studies found a significant negative effect between oil price shocks and GDP but more recently, empirical studies have reported an insignificant relationship between oil shocks and the macroeconomy. A key feature of existing research is that it applies predominantly to advanced, oil-importing countries. For oil-exporting countries, different conclusions are expected but this can only be ascertained empirically. This study conducts an empirical analysis of the effects of oil price shocks on a developing country oil-exporter—Nigeria. Our findings showed that oil price shocks do not have a major impact on most macroeconomic variables in Nigeria. The results of the Granger-causality tests, impulse response functions, and variance decomposition analysis all showed that different measures of linear and positive oil shocks have not caused output, government expenditure, inflation, and the real exchange rate. The tests support the existence of asymmetric effects of oil price shocks because we find that negative oil shocks significantly cause output and the real exchange rate.  相似文献   
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