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

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

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

LORNOXICAM-LOADED NANOSPONGES FOR CONTROLLED ANTI-INFLAMMATORY EFFECT: IN VITRO/IN VIVO ASSESSMENT

Objective: To design a controlled topical delivery system of lornoxicam (LX) in order to enhance skin permeation and treatment efficacy. Nanosponges were selected as a novel carrier for this purpose. Methods: Nanosponges were formulated via the emulsion solvent evaporation method using ethyl cellulose (polymer) and polyvinyl alcohol (surfactant). Nanosponge dispersions were characterized for colloidal properties, entrapment efficiency and in vitro release study. The nanosponge formulation (LS1) was then incorporated into carboxymethyl cellulose sodium hydrogels and evaluated for pH, viscosity and in vitro drug release. Skin irritation was evaluated, and anti-inflammatory activity was assessed via rat hind paw edema method. Results: Nanosponges were in the nano-sized range and attained a uniform round shape with a spongy structure. LS1exhibited the highest LX release after 6 h, so it was incorporated as hydrogel. Formulated hydrogels showed acceptable physicochemical parameters (pH, drug content and rheological properties). Skin irritation testing proved LX-loaded nanosponge hydrogel formulation (G1) to be non-irritant. In vivo study revealed an enhanced anti-inflammatory activity of G1 for 6 h (p<0.001). Conclusion: The developed nanosponge hydrogel is an efficient nanocarrier for improved and controlled topical delivery of LX

Comparison of cognitive function, socioeconomic level, and the health-related quality of life between epileptic patients with attention deficit hyperactivity disorder and without

Background Epilepsy is one of the most common neurological conditions. Attention deficit hyperactivity disorder (ADHD) in children with epilepsy proves to be very common. Both epilepsy and ADHD impair quality of life. We aimed to evaluate cognitive function, socioeconomic level, and quality of life (QOL) among children with ADHD and epilepsy. A total of 100 children were divided into 5 groups (20 children/group) as (I) epilepsy, (II) ADHD with epilepsy, (III) ADHD with EEG changes, (IV) ADHD without EEG changes, and (V) control. Children aged between 6 and 11 years were recruited for this study. Early Childhood Epilepsy Severity Scale (E-Chess), Conners’ Parent Rating Scale (CPRS), Wechsler Intelligence Scale for Children-3rd edition (WISC-III), socioeconomic scale for assessment of social burden and socioeconomic classes, and PedsQL (quality of life measure) assessed. Results Children with ADHD and epilepsy had the lowest PedsQL total scores and lower scores than other groups especially in performance IQ score. The highest percentage of low socioeconomic class (25%) was observed in the group of ADHD with epilepsy and the group of epilepsy. Conclusion ADHD with epilepsy is associated with low performance IQ, poor socioeconomic level, and quality of life. Pediatric Quality of Life Inventory scores show significant correlation with total IQ score in the group of ADHD with epilepsy

Review of multicast QoS routing protocols for mobile ad hoc networks

A Mobile Ad hoc NETwork (MANET) is consisting of a collection of wireless mobile nodes, which form a temporary network without relying on any existing infrastructure or centralized administration. Since the bandwidth of MANETs is limited and shared between the participating nodes in the network, it is important to efficiently utilize the network bandwidth. Multicasting can minimize the link bandwidth consumption and reduce the communication cost by sending the same data to multiple participants. Multicast service is critical for applications that need collaboration of team of users. Multicasting in MANETs becomes a hot research area due to the increasing popularity of group communication applications such as video conferencing and interactive television. Recently, multimedia and group-oriented computing gains more popularity for users of ad hoc networks. So, effective Quality of Service (QoS) multicasting protocol plays significant role in MANETs. In this paper, we are presenting an overview of set of the most recent QoS multicast routing protocols that have been proposed in order to provide the researchers with a clear view of what has been done in this field

FABRICATION OF BIOADHESIVE OCUSERT WITH DIFFERENT POLYMERS: ONCE A DAY DOSE

Objective: The objective of this current study is to fabricate ocuserts to control the drug release from chosen bioadhesive polymeric matrixes to enhance patient compliance. Ciprofloxacin HCl (CFX HCl) was selected as a model drug.Methods: Different bioadhesive polymers with different film forming capabilities namely Hydroxy Propyl Methyl Cellulose (HPMC K4M), Poly Vinyl Alcohol (PVA), Sodium Carboxy Methyl Cellulose (Na CMC), Hydroxy Propyl Cellulose (HPC), Sodium Alginate (Na Alg.), pullulan and Xanthan Gum (XG) in different ratios were used in fabricating ocuserts using solvent-casting technique. Propylene Glycol (PG) was used as a plasticizer to facilitate the fabrication process. Characterization tests of the developed ocuserts were performed as well as bioadhesive tests and in vitro release studies of the incorporated drug. The obtained results were analysed using different release kinetic models. Stability of the selected ocuserts was investigated at 40±0.5 °C and 75±5% Relative Humidity (RH) for three months' storage period. In vivo ocular irritation test was performed to investigate the safety of the formula in rabbits' eyes as well as to test the release profile and thus to estimate In vitro In vivo correlation.Results: All the prepared ocuserts showed the uniformity of film characterization and bioadhesion strength ranged from 240±66 and 158±52dyne/cm2. Selected formula from the in vitro release study tested for in vivo study showed the slow release of ciprofloxacin drug up to 24 h with no signs of eye irritancy. Results for In vitro In vivo correlation showed an excellent correlation with R2 value of 0.9982.Conclusion: PVA based ocuserts proven to be a promising once-daily, effective and safe ocular delivery system of the drug

Issues in location-based multicast routing in manets

Mobile Ad Hoc Networks (MANETs) are an autonomous system of a set of mobile nodes connected by shared wireless links, forming a temporary network without relying on any infrastructure. MANETs characteristics include self-organizing, self-configuring, multihop communication, continuous mobility and strict resource limitation. These characteristics coupled with the characteristics of the wireless communication medium make routing protocols one of the major issues to consider in MANET