Search results for "PUMP"
showing 10 items of 471 documents
An accurate optical technique for measuring the nuclear polarisation of 3He gas
2010
12 pages; International audience; In the metastability exchange optical pumping cells of our on-site production unit and of our other experimental set-ups, we use a light absorption technique to measure the 3He nuclear polarisation. It involves weak probe beams at 1083 nm, that are either perpendicular or parallel to the magnetic field and cell axis, with suitable light polarisations. When metastability exchange collisions control the populations of the sublevels in the 23S state, absolute values of the 3He ground state nuclear polarisation are directly inferred from the ratio of the absorption rates measured for these probe beams. Our report focuses on the transverse detection scheme for w…
Improving Separation of Oil and Water Using a Novel Coalescing Centrifugal Pump
2017
Abstract A novel centrifugal pump, which increases oil droplet sizes in produced water, has been developed. This paper investigates a concept of pumping pressure optimization with respect to downstream separation efficiency, for the new pump. The investigation shows that the coalescing centrifugal pump always increases the separation efficiency of a downstream hydrocyclone. Furthermore, it is seen that the pumping pressure can be adjusted to maximize the improvement. Experimental results demonstrate how pumping conditions, which minimize the volume fraction of droplets with a diameter smaller than the cut size of the hydrocyclone, maximize the separation efficiency. Finally, it is exemplifi…
Variable Step Size P&O Algorithms for Coalescing Pump/Deoiling Hydrocyclone Produced Water Treatment System
2020
This paper presents three variable step size P&O algorithms for optimizing the separation efficiency of a coalescing pump/deoiling hydrocyclone produced water treatment system. By continuously adjusting the pumping pressure, and subsequently the coalescing effect, the algorithms are used to minimize the oil concentration downstream the hydrocyclone. Due to the variable step size, the algorithms react rapidly to changes in the upstream produced water characteristics, at the same time as they reduce (or eliminate) steady-state oscillations. Based on both simulation and experimental testing, the study discusses advantages and disadvantages of the algorithms.
Methodological approach for evaluating the geo-exchange potential: VIGOR Project
2012
In the framework of VIGOR Project, a national project coordinated by the Institute of Geosciences and Earth Resources (CNR-IGG) and sponsored by the Ministry of Economic Development (MiSE), dedicated to the evaluation of geothermal potential in the regions of the Convergence Objective in Italy (Puglia, Calabria, Campania and Sicily), is expected to evaluate the ability of the territory to heat exchange with the ground for air conditioning of buildings. To identify the conditions for the development of low enthalpy geothermal systems collected and organized on a regional scale geological and stratigraphic data useful for the preparation of a specific thematic mapping, able to represent in a …
Micropollutants removal in an anaerobic membrane bioreactor and in an aerobic conventional treatment plant
2012
The paper expresses an attempt to tackle the problem due to the presence of micropollutants in wastewater which may be able to disrupt the endocrine system of some organisms. These kinds of compounds are ubiquitously present in municipal wastewater treatment plant (WWTP) effluents. The aim of this paper is to compare the fate of the alkylphenols-APs (4-(tert-octyl)) phenol, t-nonylphenol and 4-p-nonylphenol and the hormones (estrone, 17ß-estradiol and 17¿-ethinylestradiol) in a submerged anaerobic membrane bioreactor (SAMBR) pilot plant and in a conventional activated sludge wastewater treatment plant (CTP). The obtained results are also compared with the results obtained in a previous stud…
Reverse Engineering and Redesign of the Impeller of a Submersible Centrifugal Pump
2022
In this work a Reverse Engineering based approach has been implemented aiming to reconstruct the 3D shape of a strongly damaged and no longer usable impeller of a submersible centrifugal pump. After obtaining the 3D model, new designs of the impeller were investigated in terms of structural stability and corrosion resistance by changing the geometry and the material. Obtained results show the used approach can be very useful both to reproduce, by Additive Manufacturing, no longer available spare parts, so allowing to extend the useful life of old machineries and to reduce costs resulting from plant shutdowns, but also to improve the performances of old designs, making use of different mater…
MRI using hyperpolarized noble gases.
1998
The aim of this study was to review the physical basis of MRI using hyperpolarized noble gases as well as the present status of preclinical and clinical applications. Non-radioactive noble gases with a nuclear spin 1/2 (He-3, Xe-129) can be hyperpolarized by optical pumping. Polarization is transferred from circularly polarized laser light to the noble-gas atoms via alkali-metal vapors (spin exchange) or metastable atoms (metastability exchange). Hyperpolarization results in a non-equilibrium polarization five orders of magnitude higher than the Boltzmann equilibrium compensating for the several 1000 times lower density of noble gases as compared with liquid state hydrogen concentrations in…
Continuous glucose monitoring use and glucose variability in very young children with type 1 diabetes (VibRate): A multinational prospective observat…
2021
While data on the efficacy and safety of continuous glucose monitoring (CGM) exist across a broad age spectrum, it is limited in very young children with type 1 diabetes (T1D). We aimed to assess real-world data in this high-risk population, focusing on glycemic variability and metrics beyond HbA1c. A 12-month multi-national, prospective, observational, registry-based cohort study in children with T1D aged 1-7 years compared glucose control using real-time CGM and using fingerstick blood glucose monitoring (BGM) alone. The prespecified primary endpoint was a difference in coefficient of variation (CV) between the CGM users and BGM-only cohort. Among 227 individuals using insulin pumps (42% …
Glycemic Outcome Associated With Insulin Pump and Glucose Sensor Use in Children and Adolescents With Type 1 Diabetes. Data From the International Pe…
2021
OBJECTIVE Insulin delivery methods, glucose-monitoring modalities, and related outcomes were examined in a large, international, diverse cohort of children and adolescents with type 1 diabetes from the Better Control in Pediatric and Adolescent Diabetes: Working to Create Centers of Reference (SWEET) -Registry. RESEARCH DESIGN AND METHODS Participants with type 1 diabetes of >= 1 year, aged <= 18 years, and who had documented pump or sensor usage during the period August 2017-July 2019 were stratified into four categories: injections-no sensor (referent); injections + sensor; pump-no sensor; and pump + sensor. HbA(1c) and proportion of patients with diabetic ketoacidosis (DKA) or severe hyp…
Patients with type 1 diabetes transition from pediatric to adult care in Poland—an example from Silesia
2014
Transition from pediatric to the adult care system is an important issue for diabetes management. The objective was to evaluate the transition of young adults with type 1 diabetes (T1DM) from pediatric to adult diabetes care. Questionnaires were sent to all T1DM patients (166), who left pediatric diabetes care in Katowice, Poland (2003–2007). Analyzed parameters included: date of first visit and visit frequency in adult care, HbA1c (mean and final at pediatric care, HbA1c_M and F respectively, reported in questionnaire – HbA1c_Q), and history of acute complications. 132(82.5 %) responses were received. 96(73 %) patients undertook their first visit at adult clinic ≤3 months after finishing p…