Two-phase slug flow measurement using ultra-sonic techniques in combination with T-Y junctions

The accurate measurement of multiphase flows of oil/water/gas is a critical element of oil exploration and production. Thus, over the last three decades; the development and deployment of in-line multiphase flow metering systems has been a major focus worldwide. Accurate measurement of multiphase flow in the oil and gas industry is difficult because there is a wide range of flow regimes and multiphase meters do not generally perform well under the intermittent slug flow conditions which commonly occur in oil production. This thesis investigates the use of Doppler and cross-correlation ultrasonic measurements made in different high gas void fraction flow, partially separated liquid and gas flows, and homogeneous flow and raw slug flow, to assess the accuracy of measurement in these regimes. This approach has been tested on water/air flows in a 50mm diameter pipe facility. The system employs a partial gas/liquid separation and homogenisation using a T-Y junction configuration. A combination of ultrasonic measurement techniques was used to measure flow velocities and conductivity rings to measure the gas fraction. In the partially separated regime, ultrasonic cross-correlation and conductivity rings are used to measure the liquid flow-rate. In the homogeneous flow, a clamp-on ultrasonic Doppler meter is used to measure the homogeneous velocity and combined with conductivity ring measurements to provide measurement of the liquid and gas flow-rates. The slug flow regime measurements employ the raw Doppler shift data from the ultrasonic Doppler flowmeter, together with the slug flow closure equation and combined with gas fraction obtained by conductivity rings, to determine the liquid and gas flow-rates. Measurements were made with liquid velocities from 1.0m/s to 2.0m/s with gas void fractions up to 60%. Using these techniques the accuracies of the liquid flow-rate measurement in the partially separated, homogeneous and slug regimes were 10%, 10% and 15% respectively. The accuracy of the gas flow-rate in both the homogeneous and raw slug regimes was 10%. The method offers the possibility of further improvement in the accuracy by combining measurement from different regimes

Miconazole Nitrate based cubosome hydrogels for topical application

Cubosomes are discrete, sub-micron, nano-structured particles of bicontinuous cubic liquid crystalline phase. Cubosomes consist of honeycombed (cavernous) structures separating two internal aqueous channels and a large interfacial area. They are the biocompatible novel approach for the drug delivery system. The controlled release application of these nanoparticles is of a great significance in cosmeceutical and pharmaceutical fields. The present study is concerned with the design and evaluation of a novel nano-particulate system; cubosomes, loaded with miconazole nitrate (MN); which is used as antifungal agent. Cubosome dispersions were formulated by emulsification technique using different concentrations of a lipid phase monoolein and the nonionic surfactant, Poloxamer 407. The prepared cubosomal dispersions were characterized regarding dimensional distribution, particle size, and in vitro drug release. The optimum formulae were incorporated in a CMC or HPMC based hydrogels, to form cubosomal hydrogels (cubogels). The cubogels were characterized regarding in vitro release of (MN), viscosity and pH. A comparison between the cubogels and a commercially available product, Miconaz® cream, was carried out to judge their efficacy. The drug release from the commercial preparation was lower than all the prepared nano-emulsion based gel formulations. G1 and G8 showed highest drug release percent (100%) after 8 hours, in contrast the marketed formulation released (44.8%) of the drug after 8 hrs. The in vitro Miconazole nitrate release data were fitted to Korsmeyerpeppa's release model. The formulation exhibited non-fickian transport with zero order kinetics. Formulae G1, G8 and G10, that showed both small droplet size and highest extent of drug release, were microbiologically evaluated against Candida albicans (C. albicans) using agar cup diffusion method. The selected formulae showed superior antimycotic activity compared to the commercially available formulation

Miconazole Nitrate based cubosome hydrogels for topical application

Cubosomes are discrete, sub-micron, nano-structured particles of bicontinuous cubic liquid crystalline phase. Cubosomes consist of honeycombed (cavernous) structures separating two internal aqueous channels and a large interfacial area. They are the biocompatible novel approach for the drug delivery system. The controlled release application of these nanoparticles is of a great significance in cosmeceutical and pharmaceutical fields. The present study is concerned with the design and evaluation of a novel nano-particulate system; cubosomes, loaded with miconazole nitrate (MN); which is used as antifungal agent. Cubosome dispersions were formulated by emulsification technique using different concentrations of a lipid phase monoolein and the nonionic surfactant, Poloxamer 407. The prepared cubosomal dispersions were characterized regarding dimensional distribution, particle size, and in vitro drug release. The optimum formulae were incorporated in a CMC or HPMC based hydrogels, to form cubosomal hydrogels (cubogels). The cubogels were characterized regarding in vitro release of (MN), viscosity and pH. A comparison between the cubogels and a commercially available product, Miconaz® cream, was carried out to judge their efficacy. The drug release from the commercial preparation was lower than all the prepared nano-emulsion based gel formulations. G1 and G8 showed highest drug release percent (100%) after 8 hours, in contrast the marketed formulation released (44.8%) of the drug after 8 hrs. The in vitro Miconazole nitrate release data were fitted to Korsmeyerpeppa's release model. The formulation exhibited non-fickian transport with zero order kinetics. Formulae G1, G8 and G10, that showed both small droplet size and highest extent of drug release, were microbiologically evaluated against Candida albicans (C. albicans) using agar cup diffusion method. The selected formulae showed superior antimycotic activity compared to the commercially available formulation

Heterogeneous wireless networks for smart grid distribution systems: Advantages and limitations

Supporting a conventional power grid with advanced communication capabilities is a cornerstone to transferring it to a smart grid. A reliable communication infrastructure with a high throughput can lay the foundation towards the ultimate objective of a fully automated power grid with self-healing capabilities. In order to realize this objective, the communication infrastructure of a power distribution network needs to be extended to cover all substations including medium/low voltage ones. This shall enable information exchange among substations for a variety of system automation purposes with a low latency that suits time critical applications. This paper proposes the integration of two heterogeneous wireless technologies (such as WiFi and cellular 3G/4G) to provide reliable and fast communication among primary and secondary distribution substations. This integration allows the transmission of different data packets (not packet replicas) over two radio interfaces, making these interfaces act like a one data pipe. Thus, the paper investigates the applicability and effectiveness of employing heterogeneous wireless networks (HWNs) in achieving the desired reliability and timeliness requirements of future smart grids. We study the performance of HWNs in a realistic scenario under different data transfer loads and packet loss ratios. Our findings reveal that HWNs can be a viable data transfer option for smart grids. 2018 by the authors. Licensee MDPI, Basel, Switzerland.Acknowledgments: This work was made possible by the United Arab Emirates University UPAR Grant No. 31N226.Scopu

Energy absorption capability of thin-walled aluminium tubes under crash loading

This paper investigates the interaction of design factors such as tube thickness, tube length, and tube cross-sectional aspect ratio, along with friction and impacting mass on crashworthiness parameters such as specific energy absorption contact time, peak force and crush distance. The impact velocity is assumed to be constant at 15 m/s. The focus is on rectangular aluminium tubes and the analysis was carried out by using a validated finite element model. The analysis shows that the factors are not independent of each other and there is some degree of interaction between them. It was found that the trigger mechanism is a very important design factor to be included in the design of thin-walled tubes for energy absorption applications. The effect of the friction coefficient was found to be insignificant and finally, based on the interactions, it can be concluded that the most effective design would be a larger tube with small wall thickness, and a larger aspect ratio to avoid buckling.Universiti Tenaga Nasional, Malaysi

Mapping curie point depth of the west African Craton from satellite magnetic data and its implication for diamond exploration

The main objective of this work is to map the Curie depth of the West African Craton (WAC) using satellite magnetic data with the aim to provide first order evaluation, within this vast territory, for the spatial association between Curie-depth surface and known kimberlite locations. Taking into account Clifford's rule, the first and foremost exploration guideline for diamond exploration is the existence of a sufficiently thick lithosphere that expected to have a low surface heat flow. The Curie depth is closely related to the surface heat-flow conditions and lithosphere thickness. In actual fact, the only few regions that have sufficient density of surface heat flow measurements corroborate the association of these conditions with the diamond resources. To better explore in an efficient way the spatial relationship between the Curie depth and known diamondiferous primary sources within the WAC, we used GIS-based weights of evidence method to provide a quantitative analysi

An Evaluation of the Effect of a Mentoring Program on Eighth-Grade Students

The purpose of this applied dissertation study was to determine the effect of a mentoring program, the 5000 Role Models of Excellence Project, on eighth-grade graduation rates of minority male students at one middle school in South Florida. An achievement gap exists between minority and majority male students in this school district indicating a need for an intervention program for those minority males at risk of dropping out of school. Such a program would serve minority males by providing a positive role model in their lives. The 5000 Role Models of Excellence Project was utilized at this middle school in South Florida to assist minority students in forming positive relationships as they transitioned to high school. For this study, 20 parents and 20 mentors from one middle school were surveyed about their satisfaction with the program. Students were surveyed about their perceptions of the program and its impact. Students’ graduation rates were obtained from official school records and broken down by ethnicity. Students and parents were encouraged to continue their participation in the mentoring program, which provided the participants with additional resources in and out of school. The results of the study revealed improvement in graduation rates among minority male eighth-grade students enrolled in the 5000 Role Models of Excellence Project as compared to minority male eighth-grade students who did not participate in the mentoring program. Parents and mentors reported that the program assisted the students in achieving better academic and conduct grades in school. The study demonstrated the positive impact of the project on eighth-grade minority males in one middle school in Florida

Influence of the analysis technique on estimating hepatic iron content using MRI

Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/134998/1/jmri25317.pdfhttp://deepblue.lib.umich.edu/bitstream/2027.42/134998/2/jmri25317_am.pd

Performance Study on a Window Type Air Conditioner Condenser Using Alternative Refrigerant R407C

In this work, a performance study was achieved on air cooled condenser of an air-conditioning unit. An experimental investigation was carried out on two condenser designs aided by a controlled environmental zone, which was designed and constructed for the current study. The effect of ambient air temperature on the condenser performance was studied by varying the controlled zone air temperature from 30 to 50oC. The first design is a four circuits 5/16" tube diameter condenser and the second is an eight circuits design with the same diameter. The experimental results showed that, an increase in the ambient air temperature has a negative effect on COP due to the decrease in the overall heat rejected, yet has a positive effect on refrigerant side pressure drop