WorldWideScience

Sample records for cadarache swimming pool reactor

  1. Swimming pool cleaner poisoning

    Science.gov (United States)

    Swimming pool cleaner poisoning occurs when someone swallows this type of cleaner, touches it, or breathes in ... The harmful substances in swimming pool cleaner are: Bromine ... copper Chlorine Soda ash Sodium bicarbonate Various mild acids

  2. Grundfoss: Chlorination of Swimming Pools

    DEFF Research Database (Denmark)

    Hjorth, Poul G.; Hogan, John; Andreassen, Viggo

    1998-01-01

    Grundfos asked for a model, describing the problem of mixing chemicals, being dosed into water systems, to be developed. The application of the model should be dedicated to dosing aqueous solution of chlorine into swimming pools.......Grundfos asked for a model, describing the problem of mixing chemicals, being dosed into water systems, to be developed. The application of the model should be dedicated to dosing aqueous solution of chlorine into swimming pools....

  3. ITER at Cadarache; ITER a Cadarache

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2005-06-15

    This public information document presents the ITER project (International Thermonuclear Experimental Reactor), the definition of the fusion, the international cooperation and the advantages of the project. It presents also the site of Cadarache, an appropriate scientifical and economical environment. The last part of the documentation recalls the historical aspect of the project and the today mobilization of all partners. (A.L.B.)

  4. The Pool Is Not Just for Swimming

    Science.gov (United States)

    Metzker, Andrea

    2004-01-01

    Participating in water fitness workouts is one way to benefit one's health at very little cost. If the pool at a school is used only for swimming, then the benefits of having one barely causes a ripple. When the properties of water and how humans react to water are understood and applied to water activity programs, health benefits and enjoyment…

  5. Strategies for chemically healthy public swimming pools

    DEFF Research Database (Denmark)

    Hansen, Kamilla Marie Speht

    of the strategies which can be used to achieve microbiological safe water with low levels of DBPs to ensure healthy environment for bathers. There are different approaches to achieve healthy environment in public swimming pools which in this thesis are divided into three strategies: alternatives to chlorination...

  6. [Infections transmitted in swimming pools].

    Science.gov (United States)

    von Suzani, C; Hazeghi, P

    1976-01-01

    Public swimmingpools can be the source of infections due to micro-organism such as mycobacterium balnei, adeno and enteroviruses, the virus of plantar warts and molluscum contagiosum, the TRIC-Agent of swimmingpool-conjonctivitis and pathogenic fungi. The transmission of trichomonas vaginalis is considered unlikely-Water of pools, supposed to present satisfactory qualities by standard controls, was found to contain pathogenic staphylococci and pseudomonas aeruginosa. Effective preventive measures include the continuous recording of the redox-potential of the water, limiting the number of visitors to pool design specifications, better desinfection of sanitary installations, regular maintenance of technical equipment including frequent backwashing of filters and exclusion of visitors with communicable disease.

  7. Swimming Pools, Swimming pools, licensed - name, address, contact, volume, Published in 2006, Iowa Dept. of Public Health.

    Data.gov (United States)

    NSGIC GIS Inventory (aka Ramona) — This Swimming Pools dataset, was produced all or in part from Published Reports/Deeds information as of 2006. It is described as 'Swimming pools, licensed - name,...

  8. Alternative heating of a municipal swimming pool

    Energy Technology Data Exchange (ETDEWEB)

    Lazzarin, R.

    1982-03-01

    Swimming pools require great amounts of energy at low temperature levels. Therefore the application of alternative heating systems is very suitable. Four different systems are taken into account: compression heat pump, absorption heat pump, motor driven heat pump with thermal recovery, and a combined system. A short thermodynamic analysis is carried out in order to evaluate operating savings. Initial cost estimates demonstrate the advantages of each proposed solution over the conventional system.

  9. Disinfection byproducts in swimming pool: occurrences, implications and future needs.

    Science.gov (United States)

    Chowdhury, Shakhawat; Alhooshani, Khalid; Karanfil, Tanju

    2014-04-15

    Disinfection of swimming pool water is essential to deactivate pathogenic microorganisms. Many swimming pools apply chlorine or bromine based disinfectants to prevent microbial growth. The chlorinated swimming pool water contains higher chlorine residual and is maintained at a higher temperature than a typical drinking water distribution system. It constitutes environments with high levels of disinfection by-products (DBPs) in water and air as a consequence of continuous disinfection and constant organic loading from the bathers. Exposure to those DBPs is inevitable for any bather or trainer, while such exposures can have elevated risks to human health. To date, over 70 peer-reviewed publications have reported various aspects of swimming pool, including types and quantities of DBPs, organic loads from bathers, factors affecting DBPs formation in swimming pool, human exposure and their potential risks. This paper aims to review the state of research on swimming pool including with the focus of DBPs in swimming pools, understand their types and variability, possible health effects and analyze the factors responsible for the formation of various DBPs in a swimming pool. The study identifies the current challenges and future research needs to minimize DBPs formation in a swimming pool and their consequent negative effects to bathers and trainers.

  10. Chemical contaminants in swimming pools: Occurrence, implications and control.

    Science.gov (United States)

    Teo, Tiffany L L; Coleman, Heather M; Khan, Stuart J

    2015-03-01

    A range of trace chemical contaminants have been reported to occur in swimming pools. Current disinfection practices and monitoring of swimming pool water quality are aimed at preventing the spread of microbial infections and diseases. However, disinfection by-products (DBPs) are formed when the disinfectants used react with organic and inorganic matter in the pool. Additional chemicals may be present in swimming pools originating from anthropogenic sources (bodily excretions, lotions, cosmetics, etc.) or from the source water used where trace chemicals may already be present. DBPs have been the most widely investigated trace chemical contaminants, including trihalomethanes (THMs), haloacetic acids (HAAs), halobenzoquinones (HBQs), haloacetonitriles (HANs), halonitromethanes (HNMs), N-nitrosamines, nitrite, nitrates and chloramines. The presence and concentrations of these chemical contaminants are dependent upon several factors including the types of pools, types of disinfectants used, disinfectant dosages, bather loads, temperature and pH of swimming pool waters. Chemical constituents of personal care products (PCPs) such as parabens and ultraviolet (UV) filters from sunscreens have also been reported. By-products from reactions of these chemicals with disinfectants and UV irradiation have been reported and some may be more toxic than their parent compounds. There is evidence to suggest that exposure to some of these chemicals may lead to health risks. This paper provides a detailed review of various chemical contaminants reported in swimming pools. The concentrations of chemicals present in swimming pools may also provide an alternative indicator to swimming pool water quality, providing insights to contamination sources. Alternative treatment methods such as activated carbon filtration and advanced oxidation processes may be beneficial in improving swimming pool water quality.

  11. Allegheny County Public Swimming Pool, Hot Tub, and Spa Inspections

    Data.gov (United States)

    Allegheny County / City of Pittsburgh / Western PA Regional Data Center — Public swimming pool, hot tub, and spa facilities are licensed and inspected once each year to assure proper water quality, sanitation, lifeguard coverage and...

  12. Health impact of disinfection by-products in swimming pools

    Directory of Open Access Journals (Sweden)

    Cristina M. Villanueva

    2012-12-01

    Full Text Available This article is focused on the epidemiological evidence on the health impacts related to disinfection by-products (DBPs in swimming pools, which is a chemical hazard generated as an undesired consequence to reduce the microbial pathogens. Specific DBPs are carcinogenic, fetotoxic and/or irritant to the airways according to experimental studies. Epidemiological evidence shows that swimming in pools during pregnancy is not associated with an increased risk of reproductive outcomes. An epidemiological study suggested an increased risk of bladder cancer with swimming pool attendance, although evidence is inconclusive. A higher prevalence of respiratory symptoms including asthma is found among swimming pool workers and elite swimmers, although the causality of this association is unclear. The body of evidence in children indicates that asthma is not increased by swimming pool attendance. Overall, the available knowledge suggests that the health benefits of swimming outweigh the potential health risks of chemical contamination. However, the positive effects of swimming should be enhanced by minimising potential risks.

  13. Inorganic Chemical Composition of Swimming Pools in Amman-Jordan

    Directory of Open Access Journals (Sweden)

    Bety Saqarat

    2012-10-01

    Full Text Available Monitoring was carried out during summer 2011 in three types of swimming pools in Amman-Jordan. Thirty six water samples, collected from three users type of swimming pools (adults, family and infants, were examined for its major ionic composition (HCO3-, Cl-, NO3-, SO4=, Ca+2, Mg+2, Na+, K+ and PO4+4 in addition to its BOD and COD content. All of the examined samples from the swimming pools water were acceptable according to the local and WHO standards. The type and number of users as well as the maintenance of the swimming pool water influenced the water quality. The results showed that there was a noticeable increase in NO3, PO4 and Cl than other ions. All of the examined samples from the swimming pools water were acceptable according to the local and WHO standards and although the water of the infant’s users changed frequently, it showed the highest concentration of most of the parameters and Adults’ pool showed the lowest.

  14. Sanitary Conditions of Public Swimming Pools in Amman, Jordan

    Directory of Open Access Journals (Sweden)

    Ashraf Abu Aqoulah

    2008-09-01

    Full Text Available This study was carried out in the summer of 2005 and investigated all of active public swimming pools (85 out of 93 in Amman, the capital of Jordan. The aim of this study was to find out if these swimming pools are in compliance with Jordanian Standards for Swimming Pools Water (JS 1562/2004. The pools were surveyed against the water microbial quality and other physicochemical parameters indicated in the standards. Two samples from each pool were collected for microbial analysis and pools monitoring were carried out during the afternoon of the weekends when the pools are most heavily used. The results indicated overall poor compliance with the standards. Compliance of the pools water to the microbial parameters was 56.5%, for residual chlorine 49.4%, for pH 87.7%, water temperature 48.8%, and bathing load 70.6%. The results also indicated that water microbial quality deteriorated with time. Multivariate analysis showed significant association of water contamination with time of sample collection, residual chlorine, water temperature and load of swimmers. The poor compliance was attributed to lack of proper disinfection, staff training, proper maintenance, and timely inspection.

  15. Sanitary Conditions of Public Swimming Pools in Amman, Jordan

    Directory of Open Access Journals (Sweden)

    Ashraf Abu Aqoulah

    2007-12-01

    Full Text Available This study was carried out in the summer of 2005 and investigated all of active public swimming pools (85 out of 93 in Amman, the capital of Jordan. The aim of this study was to find out if these swimming pools are in compliance with Jordanian Standards for Swimming Pools Water (JS 1562/2004. The pools were surveyed against the water microbial quality and other physicochemical parameters indicated in the standards. Two samples from each pool were collected for microbial analysis and pools monitoring were carried out during the afternoon of the weekends when the pools are most heavily used. The results indicated overall poor compliance with the standards. Compliance of the pools water to the microbial parameters was 56.5%, for residual chlorine 49.4%, for pH 87.7%, water temperature 48.8%, and bathing load 70.6%. The results also indicated that water microbial quality deteriorated with time. Multivariate analysis showed significant association of water contamination with time of sample collection, residual chlorine, water temperature and load of swimmers. The poor compliance was attributed to lack of proper disinfection, staff training, proper maintenance, and timely inspection.

  16. Cryptosporidium and Giardia in Swimming Pools, Atlanta, Georgia

    Centers for Disease Control (CDC) Podcasts

    2008-05-29

    In this podcast, Dan Rutz speaks with Dr. Joan Shields, a guest researcher with the Healthy Swimming Program at CDC, about an article in June 2008 issue of Emerging Infectious Diseases reporting on the results of a test of swimming pools in the greater Atlanta, Georgia area. Dr. Shields tested 160 pools in metro Atlanta last year for Cryptosporidium and Giardia. These germs cause most recreational water associated outbreaks.  Created: 5/29/2008 by Emerging Infectious Diseases.   Date Released: 5/29/2008.

  17. Acanthamoeba species in Swimming Pools of Cairo, Egypt.

    Directory of Open Access Journals (Sweden)

    Ahmad Al-Herrawy

    2014-06-01

    Full Text Available The free-living amoebae Acanthamoeba spp. have been recognized as etiologic agents of amoebic encephalitis, keratitis, otitis, lung lesions and other skin infections mainly in immuno-compromised individuals. The purpose of this study is to detect the presence of Acanthamoeba in swimming pools in Egypt using a polymerase chain reaction (PCR method.Water samples were collected from 10 different swimming pools in Cairo, Egypt. Samples were cultured on non-nutrient agar for the detection of Acanthamoeba isolates that were confirmed by PCR amplification using genus specific primers. The molecularly confirmed Acanthamoeba isolates were morphologically identified to the species level.Members of genus Acanthamoeba were detected in 49.2% of the examined swimming-pool water samples. Morphologically, six Acanthamoeba species were isolated from the examined swimming pool water namely A. polyphaga, A.castellanii, A. rhysodes, A. mauritaniensis, A. royreba and A. triangularis. All the identified species of Acanthamoeba were molecularly confirmed to be related to the genus Acanthamoeba.The isolated species of Acanthamoeba could provoke variable degrees of infections to the swimmers. The culture method is cheaper and easier than PCR techniques that are faster for the detection of free-living amoebae.

  18. [Swimming pool lung -- extrinsic allergic alveolitis or mycobacterial disease?].

    Science.gov (United States)

    Koschel, D; Pietrzyk, C; Sennekamp, J; Müller-Wening, D

    2006-05-01

    There have been several recent reports of pulmonary disease resulting from exposure to Mycobacterium avium complex in indoor hot tubs. The disease is thought to be due either to infection or extrinsic allergic alveolitis (EAA). In this report we describe the case of a patient who developed episodes of fever, dyspnea and cough 4-6 hours after cleaning his indoor swimming pool. A diagnosis of EAA was made on finding a restrictive lung function pattern with gas exchange abnormalities, a predominant lymphocytosis in the bronchoalveolar lavage, diffuse ground-glass opacities in the lower lobes on high-resolution computer tomography, and specific IgG antibody activity to the swimming pool water. There was no precipitin reaction or specific IgG antibody activity to microbes extracted from the water. Interestingly, the water contained Mycobacterium avium complex (MAC) in huge amounts and in this case the histopathological features of the lung biopsy specimens differed from those seen in typical EAA, but were similar to those described in "hot tub lung" caused by mycobacteria. Solely by avoidance of cleaning the swimming pool, without any pharmacological treatment, the patient recovered completely within three months. To the best of our knowledge, this is the first report of EAA possibly associated with MAC exposure in a swimming pool environment.

  19. Predicting bromide incorporation in a chlorinated indoor swimming pool.

    Science.gov (United States)

    Chowdhury, Shakhawat; Mazumder, Abu Jafar; Husain, Tahir

    2016-06-01

    The water in and air above swimming pools often contain high levels of disinfection byproducts (DBPs) due to chemical reactions between chlorine- or bromine-based disinfectants and organic/inorganic matter in the source water and released from swimmers. Exposure to these DBPs, though inevitable, can pose health threats to humans. In this study, DBPs in tap water (S1), and water from a chlorinated indoor swimming pool before (S2) and after swimming (S3) were measured. The brominated species constituted the majority of DBPs formed in S1, S2, and S3. Trihalomethanes (THMs) in S3 was 6.9 (range 2.9-11.1) and 1.4 (range 0.52-2.9) times those in S1 and S2, respectively; and the haloacetic acids (HAAs) in S3 was 4.2 (range 2.5-7.5) and 1.2 (range 0.6-2.6) times those in S1 and S2, respectively. The mean THMs in air above the swimming pool before (S2-A) and after swimming (S3-A) were 72.2 and 93.0 μg/m(3), respectively, and their ranges were 36.3-105.8 and 44.1-133.6 μg/m(3), respectively. The average percentages of bromide incorporation (BI) into THMs in S1, S2, and S3 were 3.0, 9.3, and 10.6 %, respectively; and the BI into HAAs in S1, S2, and S3 were 6.6, 12.0, and 12.2 %, respectively. Several models were trained for predicting the BI into THMs and HAAs. The results indicate that additional information is required to develop predictive models for BI in swimming pools.

  20. Swimming pool attendance and respiratory symptoms and allergies among Dutch children

    NARCIS (Netherlands)

    Jacobs, J.H.; Fuertes, E.; Krop, E.J.M.; Spithoven, J.; Tromp, P.; Heederik, D.J.J.

    2012-01-01

    Objectives: To describe associations among swimming, respiratory health, allergen sensitisation and Clara cell protein 16 (CC16) levels in Dutch schoolchildren. Trichloramine levels in swimming pool air were determined to assess potential exposure levels. Methods: Respiratory health and pool attenda

  1. Swimming pool attendance and respiratory symptoms and allergies among Dutch children

    NARCIS (Netherlands)

    Jacobs, J.H.; Fuertes, E.; Krop, E.J.M.; Spithoven, J.; Tromp, P.; Heederik, D.J.J.

    2012-01-01

    OBJECTIVES To describe associations among swimming, respiratory health, allergen sensitisation and Clara cell protein 16 (CC16) levels in Dutch schoolchildren. Trichloramine levels in swimming pool air were determined to assess potential exposure levels. METHODS Respiratory health and pool attendanc

  2. Study of Fungal Contamination of Indoor Public Swimming Pools

    Directory of Open Access Journals (Sweden)

    H Nanbakhsh

    2004-06-01

    Full Text Available Fungi are found in different environments with variable distribution patterns depending on various factors. The aim of this study was determination of fungal contaminants in public swimming pools in Uromia, Iran. The fungal contaminations of four indoor swimming pools were studied by using membrane filtration and swab sampling method. Samples were collected by a manual plastic pump, in a 200 ml sterilized bottle. All samples were collected within 2 hours and then transferred to the laboratory. A total of 384 samples including water and environmental surfaces were collected and tested for the presence of fungi in different seasons within one year. In addition to the above information, some physical and chemical parameters such as temperature, residual chlorine, pH, turbidity of water and the number of swimmers were studied. Findings indicated that, the average temperature, pH, residual chlorine and turbidity of water in the swimming pools within one year were: 29.9°C, 8.1, 0.6 ppm and 0.8 NTU respectively. The most common fungi recovered were as follows: Asepergillus Spp. 56.25%, Candida spp. 22.9%, Rhizopus spp. 4.16 %, other filamentous fungi 16.6% and other yeast species 2.8%. The fungi such as Alternaria, Cladosporium, Philophora and Trichophyton mentagrophytis were isolated from dressing room, bathing room and other places out of pools. According to these results and previous studies on pools, it has been indicated that contamination by fungi in the pools is not significant in water and environment. Presence of dermatophytic fungus from dressing room is probably due to human contact.

  3. Analysis of swimming pool accidents resulting in spinal cord injury.

    Science.gov (United States)

    Green, B A; Gabrielsen, M A; Hall, W J; O'Heir, J

    1980-04-01

    This paper is a summary of a study of 72 cases of swimming-pool accidents resulting in serious injuries with the potential of permanent disability. Sixty-four of the 72 cases resulted in spinal cord injuries, 57 of which involved quadriplegic lesions. The authors observed that the majority of these injuries resulted from a lack of good judgement and common sense rather than from intoxication or pool structural deficiencies. Also of note was the lack of appropriate first-aid and extrication rendered, as well as the absence of uniform treatment and care received by the majority of the patients.

  4. Comparison of heat recovery systems in public indoor swimming pools

    Energy Technology Data Exchange (ETDEWEB)

    Lazzarin, R.M. [Istituto di Ingeneria Gestionale, Universita di Padova (Italy); Longo, G.A. [Istituto di Fisica Tecnica, Universita di Padova (Italy)

    1996-07-01

    The heating of swimming pools can be expensive in terms of energy costs and energy-saving measures which are much more effective than the simple recovery of the exhausted air are recommended. A new open-cycle absorption system is presented here, operating by chemical dehumidification on the exhausted air. It allows important energy savings of the same order as the motor-driven heat pump systems, although its technology is in principle simpler and cheaper. (Author)

  5. Report transparency and nuclear safety 2007 CEA Cadarache; Rapport transparence et securite nucleaire 2007 CEA Cadarache

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2007-07-01

    This report presents the activities of the CEA Center of Cadarache for the year 2007. The actions concerning the safety, the radiation protection, the significant events, the release control and the environmental impacts and the wastes stored on the center are discussed. More especially the report discusses the beginning of the RJH reactor construction, the fourth generation reactors research programs, the implementing of la Rotonde the new radioactive wastes management installation, the renovation of the LECA. (A.L.B.)

  6. Stade NPP. Dismantling of the reactor pool

    Energy Technology Data Exchange (ETDEWEB)

    Scharf, Daniel; Dziwis, Joachim [E.ON Anlagenservice GmbH Nukleartechnik, Gelsenkirchen (Germany); Kemp, Lutz-Hagen [KKW Stade GmbH und Co. oHG, Stade (Germany)

    2012-11-01

    Within the scope of the 4{sup th} partial decommissioning permission of Stade NPP the activated and contaminated structures of the reactor pool had to be dismantled in order to gain a completely non-radioactive reactor pool area for the subsequent clearance measurement of the reactor building. In order to achieve the aim it was intended to remove the activated pool liner sheets, its activated framework and several contaminated ventilation channels made of stainless steel, the concrete walls of the reactor pool entirely or in parts depending on their activation level, as well as the remaining activated carbon steel structures of the reactor pool bottom. Embedded in the concrete walls there were several highly contaminated excore tubes and the contaminated pool top edge, which were intended to be removed to its full extent. The contract of the Stade NPP initiated reactor pool dismantling project had been awarded to E.ON Anlagenservice GmbH (EAS) and its subsupplier sat. Kerntechnik GmbH for the concrete dismantling works and was performed as follows. In order to minimize the radiation level in the main working area in accordance with the ALARA principle, the liner sheets and middle parts of its framework were removed by means of angle grinders first, as they were the most dose rate relevant parts. As a result the primary average radiation level in the reactor pool (measured in a distance of 500 mm from the walls) was lowered from 40 {mu}Sv/h to less than 2 {mu}Sv/h. After the minimization of the radiation level in the working area the main dismantling step started with the cutting of the reactor pool walls in blocks by means of diamond rope cutters. Once a concrete block was cut out, it was transported into the fuel pool by means of a crane and crane fork, examined radiologically, marked area by area and segmented to debris by means of an electrical excavator with a hydraulic chisel. Afterwards the debris and carbon steel parts were fractioned and packed for further

  7. Inquiry in the public interest, held at Cadarache into the construction of the reactor 'Jules Horowitz' and the problems related to the public dialogue; L'enquete d'utilite publique sur la creation du 'reacteur Jules Horowitz' a Cadarache et la participation locale

    Energy Technology Data Exchange (ETDEWEB)

    Bottiglioni, F

    2007-07-15

    In this paper are presented the main points of the inquiry taken by an official board into the demand of the Cea to create a new research tool, the 'Jules Horowitz Reactor', in its research center of Cadarache. The increasing involvement of the people in the decision-making procedures dealing with important projects is summed up, so as the distinctive features of the different regulations that frame the public participation are stressed. Some improvements are suggested to carry through next inquiries faster and more easily. The participation of the public has been low: only 11 people or associations have left their remarks to the inquiry members despite the large audience that attended the different meetings and debates organized on the issue by the CNDP (national board for public debate)

  8. Improved swimming pool achieves higher reproducibility and sensitivity to effect of food components as ergogenic AIDS.

    Science.gov (United States)

    Ishihara, Kengo; Yamada, Ayumi; Mita, Yukiko; Goto, Ayako; Ishimi, Tomoe; Mabuchi, Haruko; Inoue, Kazuo; Fushiki, Tohru; Yasumoto, Kyoden

    2009-06-01

    A previously developed current swimming pool for mice has been used to evaluate many food components that enhance endurance exercise performance. In this article, to improve reproducibility, reliability and sensitivity of this assay system, we improved the spout part to generate a uniform current and divided the pool into six lanes to avoid physical interference between swimming mice. The stability of the current flow was assessed by measuring the surface current speed and water volume from the spout part. Maximum swimming times of ddY and BALB/c mice were measured to assess the reproducibility of the maximum swimming time. The improvement in sensitivity compared to the original equipment was estimated under three physiological conditions: low carbohydrate diet feeding, low blood hemoglobin level, and carbohydrate supplementation during exercise. The new spout part improved uniformity and quick adjustment of surface current, yielding an increase of workload in a stepwise manner during swimming. Exercise workload was increased in proportion to surface current speed, as evidenced by cadence of kicks and serum lactic acid levels. The improved swimming pool showed higher reproducibility of swimming time until fatigue (pswimming time was improved in the swimming pool. The improved swimming pool yielded higher sensitivity for low carbohydrate diet feeding (pswimming pool. The improvement of the swimming pool achieved higher sensitivity and reproducibility in assessing various diet and food components compared to the original swimming pool.

  9. Evaluation and Treatment of Swimming Pool Avoidance Exhibited by an Adolescent Girl with Autism

    Science.gov (United States)

    Rapp, John T.; Vollmer, Timothy R.; Hovanetz, Alyson N.

    2005-01-01

    We evaluated and treated swimming pool avoidance that was exhibited by a 14-year-old girl diagnosed with autism. In part, treatment involved blocking for flopping (dropping to the ground) and elopement (running away from the pool) and access to food for movements toward a swimming pool. Treatment also involved reinforcement for exposure to various…

  10. Incidence of otitis externa following swimming pool attendance--a case study in 6 indoor pools

    Energy Technology Data Exchange (ETDEWEB)

    Borneff, M.; Geyer, G.

    1982-08-01

    A bacteriological study of the microflora in the auditory meatus of patients with otitis externa after swimming in correlation to the water flora was done during winter 80/81. Six indoor-pools (monthly controls ahead had proven unobjectionable water quality) were analyzed daily, while all swimmers were asked to come for otologic examination whenever symptoms of otitis externa appeared. In a control group without otitis externa the auditory canal was inspected and swabs were taken immediately after swimming. The results indicate, that a short term contamination of the ear canal is possible by swimming in water of unobjectionable quality; this however does not necessarily lead to clinical appearances. Since the incidence of otitis externa in our study (0.01%) was not higher than the morbidity rate in nonswimmers, the data support the concept of the multiplex etiology for otitis externa.

  11. Swimming Lessons: Learning, New Materialisms, Posthumanism, and Post Qualitative Research Emerge through a Pool Poem

    Science.gov (United States)

    McKnight, Lucinda

    2016-01-01

    This article shifts from the formal learning spaces of school and university to an Australian public swimming pool to playfully engage some of the dilemmas that recent theory poses for curriculum studies. The article enacts multiple diffractions (Barad, 2007) as theory becomes swimming and swimming becomes theory, and ideas and movements are…

  12. Energy conservation strategies for sports centers: Pt. B. Swimming pools

    Energy Technology Data Exchange (ETDEWEB)

    Trianti-Stourna, E.; Theofylaktos, C.; Santamouris, M.; Lazaropoulou, G.; Papanikolaou, N. [Athens Univ. (Greece). Dept. of Applied Physics; Spyropoulou, K. [Spyropoulou and Associares, Architects and Planners, Athens (Greece); Droutsa, K.; Balaras, C.A.; Asimakopoulos, D.N. [IMPAE, National Observatory of Athens (Greece)

    1998-04-01

    This paper summarizes the results from a number of energy audits and the analysis performed in order to improve indoor conditions and optimize energy use, in Hellenic indoor swimming pools, performed for the European Commission, in the framework of the SAVE program. The aim of this work was to investigate the technical, functional and administrative obstacles for energy conservation in sports centers (including sports halls) and to propose practical and cost-effective solutions for improving their energy efficiency, indoor thermal and visual comfort throughout the year. The work concentrated on retrofitting of existing buildings, although the proposed design and management principles could also be followed in new projects in the area of sports and recreation facilities. (orig.)

  13. Analysis of enterovirus and adenovirus presence in swimming pools in Cyprus from 2007-2008.

    Science.gov (United States)

    Bashiardes, S; Koptides, D; Pavlidou, S; Richter, J; Stavrou, N; Kourtis, C; Papageorgiou, G T; Christodoulou, C G

    2011-01-01

    An analysis was carried out to determine the presence of enteroviruses and adenoviruses in public swimming pools in Cyprus. The effectiveness of the commonly implemented disinfection procedure of chlorination was confirmed by determination of bacteriological markers. Analysis of viral presence was carried out by sampling random swimming pools from the five major cities in Cyprus during a period of 21 months spanning from April 2007 to December 2008. A 10 I sample was taken from each swimming pool to be tested and was subsequently concentrated via membrane filtration using a new methodological approach for virus elution. Concentrated samples were analysed using of a Real Time Polymerase Chain Reaction (PCR) TaqMan probe based approach to detect the presence of enteroviruses and adenoviruses. Over the period of 21 months a total of 126 swimming pools were sampled and analysed. In four swimming pools enteroviruses were detected, in one pool echovirus 18 was identified, in two pools echovirus 30 was identified and in one other pool poliovirus Sabin 1 was identified. Similarly, in four swimming pools adenoviruses were detected, in all four adenovirus 41 was identified. Bacteriological marker analysis showed that 98% of pools complied with Cyprus regulations.

  14. Bacteriological Assessment of Water Quality of Public Swimming Pools in the Accra Metropolis, Ghana

    Directory of Open Access Journals (Sweden)

    George A. Pesewu

    2015-04-01

    Full Text Available Water is essential for life and in most parts of the world including Ghana it is used for various activities such as drinking, bathing and recreational purposes. The objective of this study was to assess the bacteriological quality of swimming pools’ water in the Accra Metropolis. Five swimming pools were selected randomly and a research team visited the pools to collect water samples and at the same time administer short questionnaires about the characteristics of the pools. The average number of swimmers, swimming bathing loads, average age group of pool users, methods of disinfection, type of chlorine used, recycling, and treatment of the water before and after use were investigated. During the visit, water samples were collected for total coliform, Escherichia coli, Pseudomonas aeruginosa and Staphylococcus aureus counts using the Membrane Filtration (MF method and cultured on chromogenic media. Most (60% of the selected swimming pools had a bathing load≤20 per day. The operators of the pools disinfect their pools’ water with chorine but majority (60% of the pool operators chlorinated their pools manually with powdered chlorine. The 20 water samples investigated show that 48% of swimming pools water was contaminated with S. aureus, 30.4% with Ps. aeruginosa , 20.9% with total coli form and 0.7% with E. coli. The E. coli count found in this study was very low indicating that the selected swimming pools were not feacally polluted at the time of sampling. It is recommended that future studies should use large sample sizes.

  15. Survey of bacterial contamination of environment of swimming pools in Yazd city, in 2013

    Directory of Open Access Journals (Sweden)

    Hossein Jafari Mansoorian

    2015-09-01

    Full Text Available Background: Infections are readily transmitted as a result of bacterial contamination of swimming pools. Therefore, hygiene and preventing the contamination of swimming pools is of particular importance. The objective of this study was to determine the amount of bacterial contamination in indoor pools of Yazd in 2013. Methods: In this descriptive and analytical study, all indoor swimming pools of Yazd (12 pools were evaluated during the spring and summer of 2013, in terms of bacterial contamination. In order to determine contamination, a sterile cotton swab was used for sampling. On average, 45 samples were taken from different surfaces in each pool (shower, dressing room, sitting places in sauna, platforms and around the pool. In total, about 540 samples from all pools were tested for bacterial contamination. Results: The results show that from 540 samples, bacterial contamination was observed in about 93 samples (17.22%; and was seen more in showers, edges of the pool and jacuzzis, and the slippers used in swimming pools. The most important isolated bacteria types were E. coli, Actinobacteria, Pseudomonas alcaligenes, Pseudomonas aeruginosa and Klebsiella pneumonia. Conclusion: The results indicate the presence of bacterial contamination on the surface of these places. It is recommended that health authorities should pay more attention to cleaning and disinfecting surfaces around the pool, showers, dressing rooms etc, to prevent infectious disease transfer as a result of contact with contaminated swimming pool surfaces.

  16. Mathematical modelling and simulation of the thermal performance of a solar heated indoor swimming pool

    Directory of Open Access Journals (Sweden)

    Mančić Marko V.

    2014-01-01

    Full Text Available Buildings with indoor swimming pools have a large energy footprint. The source of major energy loss is the swimming pool hall where air humidity is increased by evaporation from the pool water surface. This increases energy consumption for heating and ventilation of the pool hall, fresh water supply loss and heat demand for pool water heating. In this paper, a mathematical model of the swimming pool was made to assess energy demands of an indoor swimming pool building. The mathematical model of the swimming pool is used with the created multi-zone building model in TRNSYS software to determine pool hall energy demand and pool losses. Energy loss for pool water and pool hall heating and ventilation are analyzed for different target pool water and air temperatures. The simulation showed that pool water heating accounts for around 22%, whereas heating and ventilation of the pool hall for around 60% of the total pool hall heat demand. With a change of preset controller air and water temperatures in simulations, evaporation loss was in the range 46-54% of the total pool losses. A solar thermal sanitary hot water system was modelled and simulated to analyze it's potential for energy savings of the presented demand side model. The simulation showed that up to 87% of water heating demands could be met by the solar thermal system, while avoiding stagnation. [Projekat Ministarstva nauke Republike Srbije, br. III 42006: Research and development of energy and environmentally highly effective polygeneration systems based on using renewable energy sources

  17. Occurrence and human exposure of parabens and their chlorinated derivatives in swimming pools.

    Science.gov (United States)

    Li, Wenhui; Shi, Yali; Gao, Lihong; Liu, Jiemin; Cai, Yaqi

    2015-11-01

    As an emerging group of endocrine-disrupting chemicals, parabens have attracted growing attention due to their potential effects on human health. In the present study, the occurrence and distribution of eight parabens, four chlorinated parabens, and their common hydrolysis product, p-hydroxybenzoic acid (PHBA), were investigated in 39 swimming pools in Beijing, China. Methyl paraben and propyl paraben were the predominant compounds in swimming pools, accounting for 91.2 % of the total parabens. It is noteworthy that octyl paraben, a paraben with longer chain, was firstly detected in this study. There were several factors affecting the levels of parabens among the 39 swimming pools. The concentrations of parabens and chlorinated derivatives detected in indoor pools (144 ng L(-1)) were roughly 20-fold higher than those in outdoor pools (6.78 ng L(-1)). Hotel pools appear to present higher level of target compounds (361 ng L(-1)) than that in health club (228 ng L(-1)), municipal (130 ng L(-1)), school (75.6 ng L(-1)), and community pools (63.0 ng L(-1)). Moreover, the level of these compounds in pools during weekends (174 ng L(-1)) was much higher than that during weekdays (52.3 ng L(-1)). The dynamics of target compounds were also investigated to provide a general trend of the level of parabens in a school indoor swimming pool during a 14-week period. Human exposure assessment was conducted to estimate the potential risk of exposure to parabens and their chlorinated derivatives in swimming pools. Considering the total exposure dose of multiple parabens, human exposure to parabens from the water of swimming pools is negligible. However, the threat of these parabens to children in swimming pool should be concerned.

  18. Disinfection by-product formation of UV treated swimming pool water

    DEFF Research Database (Denmark)

    Spiliotopoulou, Aikaterini; Hansen, Kamilla Marie Speht; Andersen, Henrik Rasmus

    2015-01-01

    Water samples from 3 indoor swimming pool facilities were tested to evaluate UV-induced effects on swimming pool water chemistry. Concentration change of several DBPs was investigated in experiments including medium pressure UV treatment with and without chlorine and post-UV chlorination. Post...... could be replicated by performing the DBP formation assay with higher chlorine concentrations to simulate extended chlorination. Post-UV chlorination of water from a swimming pool that continuously uses UV treatment to control combined chlorine could not induce secondary formation of DBPs...

  19. Water treatment in public swimming pools - reduction of energy consumption; Vandbehandling i svoemmebade - reduktion af energiforbrug

    Energy Technology Data Exchange (ETDEWEB)

    Hammerich, H.; Radisch, N. (Ramboell, Koege (Denmark)); Olesen, Jens Christian (Gladsaxe Sportscenter, Gladsaxe (Denmark)) (and others)

    2010-04-15

    Measurements were made in five public swimming baths, and energy savings were achieved using new filters, pumps, water treatment control depending on bather load, etc. In a 50 metre pool, electricity consumption for water treatment decreased by 50%, and in a hot-water/paddling pool, electricity consumption decreased by 30-40% while still maintaining satisfactory water quality - even during periods of heavy bather load. In another swimming bath, ventilation electricity consumption was reduced by 15%. The results will e.g. be used to revise the Danish executive order on swimming pools and water quality to allow bather load-dependent water circulation. (ln)

  20. Energy saving with heat pumps in indoor swimming pools; Energiebesparing met warmtepompen in overdekte zwembaden

    Energy Technology Data Exchange (ETDEWEB)

    Langreck, J. [Colibri, Vaals (Netherlands)

    1997-01-01

    The article is based on the results of a study in which heat pumps and heat recovery equipment for indoor swimming pools are compared. By means of an average, reference indoor swimming pool the effects of energy savings and costs of different combinations of equipment are compared. It is concluded that more energy can be saved by a heat pump than by a heat recovery installation, although the payback period is longer for heat pumps. In all cases, an individual optimization of the total system for a specific swimming pool is decisive for the success of the energy saving investment costs. 3 figs., 1 ill., 2 tabs.

  1. Genotoxic Effects in Swimmers Exposed to Disinfection By-products in Indoor Swimming Pools

    Science.gov (United States)

    Kogevinas, Manolis; Villanueva, Cristina M.; Font-Ribera, Laia; Liviac, Danae; Bustamante, Mariona; Espinoza, Felicidad; Nieuwenhuijsen, Mark J.; Espinosa, Aina; Fernandez, Pilar; DeMarini, David M.; Grimalt, Joan O.; Grummt, Tamara; Marcos, Ricard

    2010-01-01

    Background Exposure to disinfection by-products (DBPs) in drinking water has been associated with cancer risk. A recent study (Villanueva et al. 2007; Am J Epidemiol 165:148–156) found an increased bladder cancer risk among subjects attending swimming pools relative to those not attending. Objectives We evaluated adults who swam in chlorinated pools to determine whether exposure to DBPs in pool water is associated with biomarkers of genotoxicity. Methods We collected blood, urine, and exhaled air samples from 49 nonsmoking adult volunteers before and after they swam for 40 min in an indoor chlorinated pool. We estimated associations between the concentrations of four trihalomethanes (THMs) in exhaled breath and changes in micronuclei (MN) and DNA damage (comet assay) in peripheral blood lymphocytes before and 1 hr after swimming; urine mutagenicity (Ames assay) before and 2 hr after swimming; and MN in exfoliated urothelial cells before and 2 weeks after swimming. We also estimated associations and interactions with polymorphisms in genes related to DNA repair or to DBP metabolism. Results After swimming, the total concentration of the four THMs in exhaled breath was seven times higher than before swimming. The change in the frequency of micronucleated lymphocytes after swimming increased in association with higher exhaled concentrations of the brominated THMs (p = 0.03 for bromodichloromethane, p = 0.05 for chlorodibromomethane, p = 0.01 for bromoform) but not chloroform. Swimming was not associated with DNA damage detectable by the comet assay. Urine mutagenicity increased significantly after swimming, in association with the higher concentration of exhaled bromoform (p = 0.004). We found no significant associations with changes in micronucleated urothelial cells. Conclusions Our findings support potential genotoxic effects of exposure to DBPs from swimming pools. The positive health effects gained by swimming could be increased by reducing the potential health

  2. [Swimming pool suction injury: etiology, profylaxis and management].

    Science.gov (United States)

    Škach, J; Kašák, P; Šrám, J

    2015-01-01

    Swimming pool suction injuries are unique and rare with a substantive risk of fatal consequences. Little children under the age of 8 are the most frequent victims with serious injuries. Drownings of different seriousness are also a usual part of accidents. The case of a 19 year old man trapped in the gluteal area by a unsecured suction drainage hole illustrates the uniqueness of this problem in an interesting way. Prophylactic arrangements are well known but the problem is with their strict application. Fatal causes excluding drowning include hypovolemic shock from the sudden redistribution of intersticial fluid and blood and also the evisceration of the bowel and other abdominal organs. Localised often bizarre and large swellings and sufusions can be treated nonoperatively in the vast majority of cases. For the prevention of these injuries it is important to inform the public and increase their awareness to these injuries. It is also crucial for the correct management of these injuries a deeper awareness of this issue and a sharing of experiences and solutions with other experts.Key words: vacuum - accident - entrapment - compartment syndrome.

  3. Measurement of Chloroform in Swimming Pools' Waters and Swimmers’ Blood

    Directory of Open Access Journals (Sweden)

    S Shegefti

    2009-12-01

    Full Text Available "nBackground: A new microextraction method named dispersive liquid-liquid microextraction (DLLME for determination of chloroform in pool water and blood of swimmers after swimming is described."nMethods: This method was performed based on coupling dispersive liquid-liquid microextraction (DLLME with gas chromatog­raphy-mass spectrometry (GC-MS. Methanol and trichloroethylenes were used as the disperser solvent and the extrac­tion solvents, respectively. The volumes of these solvents were optimized for pool water by central composite design. The study involved three indoor swimming pools and nine swimmers."nResults: Chloroform concentration of pool water was 118-135 µg L-1 and of blood ranged from 1.26 to 1.66 µg L-1."nConclusion: Indoor swimming pools are closed environments presenting detectable levels of trihalomethanes (THMs. Chloro­form (CHCl3 is the most represented THMs. Therefore, the presence of CHCl3 may be considered representative of the THMs. The new method DLLME was applied for determination of CHCl3 in pool water and blood of swimmers after swim­ming inside the indoor swimming pool. The method was optimized by experimental design. Chloroform concentra­tions in the specified pool waters were 135, 124, 118 µg L-1.

  4. The IRSN Institute of radiation protection and nuclear safety Cadarache Center; L'IRSN Institut de Radioprotection et de Surete Nucleaire Centre de Cadarache

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2002-07-01

    The research programs of the IRSN in the Cadarache Center concern the nuclear safety (reactor safety, nuclear fuels behavior during accidents, fires in nuclear installations), the protection and the control of radioactive materials, the human and the environment protection. The programs are presented and discussed. This presentation includes also the regional impact of the Institute at Cadarache (economical impact, relations with the universities and international meetings). (A.L.B.)

  5. Occurrence and health risk assessment of halogenated disinfection byproducts in indoor swimming pool water.

    Science.gov (United States)

    Hang, Chen; Zhang, Beibei; Gong, Tingting; Xian, Qiming

    2016-02-01

    Swimming pool disinfection byproducts (DBPs) have become a concern in many countries all over the world. In this study, the concentrations of several categories of DBPs, including trihalomethanes (THMs), haloacetic acids (HAAs), haloacetonitriles (HANs), haloketones (HKs) and trichloronitromethane (TCNM), in 13 public indoor swimming pools in Nanjing, China were determined, the correlations between DBPs and water quality parameters as well as between different DBP categories were evaluated, and the health risks of the DBPs to human were examined. The results indicate that the DBP levels in the swimming pools in Nanjing were relatively high, with HAAs as the most dominant category, followed by THMs, HANs, HKs and TCNM sequentially. Bromochloroacetic acid (BCAA), trichloromethane (TCM), dichloroacetonitrile (DCAN), and 1,1,1-trichloropropanone (1,1,1-TCP) were the most dominant species among HAAs, THMs, HANs, and HKs, respectively. For all the different categories of DBPs, the concentrations in the pool disinfected with ozonation/chlorination were lower than those in the pool disinfected with chlorination. The DBP levels were generally not affected by the number of swimmers and the DBP levels on different dates were relatively stable. Besides, the chlorine residual seemed to be a critical concern in most of the swimming pools in this study. Moreover, there were some correlations between DBPs and water quality parameters as well as between different DBP categories. It is to be noted that the predicted cancer and health risks of the DBPs in these swimming pools were generally higher than the regulatory limits by USEPA, and thus DBPs in these swimming pools should be concerned.

  6. Laboratory studies on the effect of ozonation on THM formation in swimming pool water

    DEFF Research Database (Denmark)

    Hansen, Kamilla Marie Speht; Spiliotopoulou, Aikaterini; Cheema, Waqas Akram

    2015-01-01

    Water samples from indoor swimming pool were ozonated at different pH values to evaluate the effect of pH on decomposition of ozone in swimming pool water. Furthermore, drinking and pool water were repeatedly ozonated followed by chlorination to evaluate THM formation. Decomposition of ozone...... was not affected by pH in the range relevant to swimming pools (pH 6.8 – 7.8) and a half-life time at 10-12 min was obtained. Repeating the ozonation, the decomposition of ozone increased at the second dose of ozone added (t½,2=8 min) and then decreased again at the third and fourth dose of ozone (t½,3=17 min; t...... chlorine for drinking water as lower TTHM formation occurred than in non-ozonated samples. For pool water, a higher TTHM formation was observed in ozonated than non-ozonated pool water. Thus, it was observed that ozone reacts markedly different in swimming pool water from the known pattern in drinking...

  7. Analytic Assessment of Microbial Water Quality in Public Swimming Pools of Tehran in 2013

    Directory of Open Access Journals (Sweden)

    A Beiki

    2016-06-01

    Full Text Available Background and objectives: Swimming is one of the most popular sport fields and entertainments that has considerable benefits for human health, but on the other hand microbial water contamination in swimming pools through transmission and spread of infectious diseases is a significant threat against public health. In this study, microbial water quality of all public swimming pools in Tehran were assessed and effective factors on microbial water quality were analyzed. Materials and Methods: This cross-sectional study with the analytical approach was performed in 2013. The whole public swimming pools in Tehran were inspected and water samples were taken for measurement of microbial indicators including thermotolerant coliforms, heterotrophic plate count (HPC, and physicochemical parameters affecting the microbial water quality including turbidity, free residual chlorine and pH and an integrated swimming pool microbial water quality index were used to describe the overall situation. Operational parameters with probable effects on microbial water quality were checked through inspection using a checklist. Results: The assessment of the swimming pool microbial water quality indicated that the compliance rates of thermotolerant coliforms and HPC were 91.4 and 84.5%, respectively. Compliance rates of free residual chlorine, turbidity, Ph, and temperature were also obtained to be 82.7, 45.5, 85.6, and 65.4% respectively. Based on the integrated swimming pool microbial water quality index, the proportions of swimming pools with excellent and good microbial water quality were 39.6 and 50.4% respectively and the others had not proper microbial water quality. The parameters of water free residual chlorine and turbidity, swimmer density, water recirculation period, dilution amount, cleaning, usage rates of shower and disinfection basin and operation of water treatment systems had significant effects on the microbial indicators (P<0.05. Conclusion: The study

  8. Study of the Pollution Condition of Swimming Pools in Sari City for the Staphylococcus aureus

    Directory of Open Access Journals (Sweden)

    Z Yousefi

    2009-11-01

    Full Text Available "nBackgrounds and Objectives: Swimming pools water if not disinfected properly can be one of the infection sources of different microorganisms such as staphylococcus. This study is to aware the authorities and users about the conditions existed in sheltered swimming pools in Sari and to believe the contamination of the water there, related to the existence of staphylococcus aureus. "nMaterials and Method: In this descriptive study 32 specimens collected randomly from 15 swimming pools in action during three months from 60 cm deep under specific conditions in sterile containers and taken to the laboratory of health college in 2 hrs and were analyzed for the contamination from staphylococcus aureus and some other parameters like temperature, pH, chlorine residual and opacity on the basis of microbiological and standard methods. "nResult: Results showed an average temperature of 27.08 degree Celsius, PH=7.6, average chlorine residual 1 mil/l and opacity average was 77 NTU % and the highest contamination from staphylococcus aureus (29.3 % in C and the lowest (10.19 % was observed in D swimming pool. Furthermore this analysis showed that in 90% of specimens there was a direct relationship between the ratio of chlorine residual, times of swimming, water temperature and the number of staphylococcus. "nConclusion: Swimming pools water if not disinfected properly can be one of the infection sources of different microorganisms such as staphylococcus. Some suggestions inorder to optimization of the swimming pools condition presented in this paper.

  9. Determination of Monochloroacetic Acid in Swimming Pool Water by Ion Chromatography-Conductivity Detection

    Directory of Open Access Journals (Sweden)

    Maria Pythias B. Espino

    2013-02-01

    Full Text Available In this study, an analytical method involving ion chromatography with conductivity detection was developed and optimized for the determination of monochloroacetic acid in swimming pool water. The ion chromatographic method has a detection limit of 0.02 mg L-1 and linear range of 0.05 to 1.0 mg L-1 with correlation coeff icient of 0.9992. The method is reproducible with percent RSD of 0.052% (n=10. The recovery of monochloroacetic acid spiked in different water types (bottled, tap and swimming pool water ranged from 28 to 122%. In dilute solutions, chloride and bromide were simultaneously analyzed along with monochloroacetic acid using the optimized method. Chloride and bromide have detection limits of 0.01 to 0.05 mg L-1, respectively. The usefulness of the ion chromatographic method was demonstrated in the analysis of monochloroacetic acid in swimming pool water samples. In such highly-chlorinated samples, an Ag/H cartridge was used prior to the ion chromatographic determination so as to minimize the signal due to chloride ion. Monochloroacetic acid was detected in concentrations between 0.020 and 0.093 mg L-1 in three of the six swimming pool water samples studied. The presence of monochloroacetic acid in the swimming pool water samples suggests the possible occurrence of other disinfection by-products in these waters.

  10. Determination of Monochloroacetic Acid in Swimming Pool Water by Ion Chromatography-Conductivity Detection

    Directory of Open Access Journals (Sweden)

    Maria Pythias B. Espino

    2013-12-01

    Full Text Available In this study, an analytical method involving ion chromatography with conductivity detection was developed and optimized for the determination of monochloroacetic acid in swimming pool water. The ion chromatographic method has a detection limit of 0.02 mg L-1 and linear range of 0.05 to 1.0 mg L-1 with correlation coeff icient of 0.9992. The method is reproducible with percent RSD of 0.052% (n=10. The recovery of monochloroacetic acid spiked in different water types (bottled, tap and swimming pool water ranged from 28 to 122%. In dilute solutions, chloride and bromide were simultaneously analyzed along with monochloroacetic acid using the optimized method. Chloride and bromide have detection limits of 0.01 to 0.05 mg L-1, respectively. The usefulness of the ion chromatographic method was demonstrated in the analysis of monochloroacetic acid in swimming pool water samples. In such highly-chlorinated samples, an Ag/H cartridge was used prior to the ion chromatographic determination so as to minimize the signal due to chloride ion. Monochloroacetic acid was detected in concentrations between 0.020 and 0.093 mg L-1 in three of the six swimming pool water samples studied. The presence of monochloroacetic acid in the swimming pool water samples suggests the possible occurrence of other disinfection by-products in these waters.

  11. Monitoring organic loading to swimming pools by fluorescence excitation–emission matrix with parallel factor analysis (PARAFAC)

    DEFF Research Database (Denmark)

    Seredynska-Sobecka, Bozena; Stedmon, Colin; Boe-Hansen, Rasmus

    2011-01-01

    Fluorescence Excitation–Emission Matrix spectroscopy combined with parallel factor analysis was employed to monitor water quality and organic contamination in swimming pools. The fluorescence signal of the swimming pool organic matter was low but increased slightly through the day. The analysis...... revealed that the organic matter fluorescence was characterised by five different components, one of which was unique to swimming pool organic matter and one which was specific to organic contamination. The latter component had emission peaks at 420nm and was found to be a sensitive indicator of organic...... loading in swimming pool water. The fluorescence at 420nm gradually increased during opening hours and represented material accumulating through the day....

  12. A risk assessment of Pseudomonas aeruginosa in swimming pools: a review.

    Science.gov (United States)

    Rice, Scott A; van den Akker, Ben; Pomati, Francesco; Roser, David

    2012-06-01

    Despite routine monitoring and disinfection, treated swimming pools are frequently contaminated with the opportunistic pathogen Pseudomonas aeruginosa, which can represent a significant public health threat. This review was undertaken to identify the current understanding of risk factors associated with pool operation with respect to P. aeruginosa. The ecology and factors that promote growth of P. aeruginosa in the pool environment are complex and dynamic and so we applied a systematic risk assessment approach to integrate existing data, with the aim to improve pool management and safety. Sources of P. aeruginosa, types of infections, dose responses, routes of transmission, as well as the efficacy of current disinfectant treatments were reviewed. This review also highlights the critical knowledge gaps that are required for a more robust, quantitative risk assessment of P. aeruginosa. Quantitative risk management strategies have been successfully applied to drinking water systems and should similarly be amenable to developing a better understanding of the risk posed by P. aeruginosa in swimming pools.

  13. Safety belt promotion at community swimming pools :effects of policy, rewards, prompts, and education

    OpenAIRE

    Gilmore, Michael Richard

    1990-01-01

    Data on safety belt use were collected at two swimming pools over three consecutive summers. The impact of several variables upon safety belt use was examined. First, an Intervention Program (IP) was designed, comprised of Promotional, Reward, and Feedback components. Second, an Awareness/Education (AE) strategy was introduced to children enrolled in swim lessons. Third, belt use was examined before and after a mandatory safety belt use law (BUL) was enacted in Virginia. The moderating ef...

  14. Production of various disinfection byproducts in indoor swimming pool waters treated with different disinfection methods.

    Science.gov (United States)

    Lee, Jin; Jun, Myung-Jin; Lee, Man-Ho; Lee, Min-Hwan; Eom, Seog-Won; Zoh, Kyung-Duk

    2010-11-01

    In this study, the concentrations of disinfection byproducts (DBPs), including trihalomethanes (THMs; chloroform, bromodichloromethane, dibromochloromethane, and bromoform), haloacetic acids (HAAs; dichloroacetic acid and trichloroacetic acid), haloacetonitriles (HANs; dichloroacetonitrile, trichloroacetonitrile, bromochloroacetonitrile, and dibromoacetonitrile), and chloral hydrate (CH) were measured in 86 indoor swimming pools in Seoul, Korea, treated using different disinfection methods, such as chlorine, ozone and chlorine, and a technique that uses electrochemically generated mixed oxidants (EGMOs). The correlations between DBPs and other environmental factors such as with total organic carbon (TOC), KMnO(4) consumption, free residual chlorine, pH, and nitrate (NO(3)(-)) in the pools were examined. The geometric mean concentrations of total DBPs in swimming pool waters were 183.1±2.5μg/L, 32.6±2.1μg/L, and 139.9±2.4μg/L in pools disinfected with chlorine, ozone/chlorine, and EGMO, respectively. The mean concentrations of total THMs (TTHMs), total HAAs (THAAs), total HANs (THANs), and CH differed significantly depending on the disinfection method used (P<0.01). Interestingly, THAAs concentrations were the highest, followed by TTHMs, CH, and THANs in all swimming pools regardless of disinfection method. TOC showed a good correlation with the concentrations of DBPs in all swimming pools (chlorine; r=0.82, P<0.01; ozone/chlorine; r=0.52, P<0.01, EGMO; r=0.39, P<0.05). In addition, nitrate was positively correlated with the concentrations of total DBPs in swimming pools disinfected with chlorine and ozone/chlorine (chlorine; r=0.58; ozone/chlorine; r=0.60, P<0.01), whereas was negative correlated with the concentrations of total DBPs (r=-0.53, P<0.01) in the EGMO-treated pools.

  15. Optimal pH in chlorinated swimming pools - balancing formation of by-products

    DEFF Research Database (Denmark)

    Hansen, Kamilla Marie Speht; Albrechtsen, Hans-Jørgen; Andersen, Henrik Rasmus

    2013-01-01

    In order to identify the optimal pH range for chlorinated swimming pools the formation of trihalomethanes, haloacetonitriles and trichloramine was investigated in the pH-range 6.5–7.5 in batch experiments. An artificial body fluid analogue was used to simulate bather load as the precursor for by.......7 or lower. An optimal pH range for by-products formation in swimming pools was identified at pH 7.0–7.2. In the wider pH range (pH 6.8–7.5) the effect on by-product formation was negligible. Swimming pools should never be maintained at lower pH than 6.8 since formation of both haloacetonitriles...

  16. Particles in swimming pool filters – Does pH determine the DBP formation?

    DEFF Research Database (Denmark)

    Hansen, Kamilla Marie Speht; Willach, Sarah; Mosbæk, Hans

    2012-01-01

    The formation was investigated for different groups of disinfection byproducts (DBPs) during chlorination of filter particles from swimming pools at different pH-values and the toxicity was estimated. Specifically, the formation of the DBP group trihalomethanes (THMs), which is regulated in many...... or initial free chlorine concentrations the particles were chlorinated at different pH-values in the relevant range for swimming pools. THM and HAA formations were reduced by decreasing pH while HAN formation increased with decreasing pH. Based on the organic content the relative DBP formation from...

  17. Fungal Contamination of Indoor Public Swimming Pools, Ahwaz, South-west of Iran

    Directory of Open Access Journals (Sweden)

    A Rafiei

    2010-09-01

    Full Text Available "nBackground: Using public swimming pools during different seasons and poor health behavior could be responsible in transmis­sion of fungal disease through pool water and its environment. Therefore, this research was conducted to investi­gate fungal agents of indoor public swimming pools of Ahwaz, capital city of Khouzestan Province, south-west of Iran."nMethods: Ten indoor swimming pools of Ahwaz were investigated during two seasons for 6 months. Water specimens were col­lected by pump and environment samples including shower-bath area, margin of pool walls, dressing rooms, and slip­pers, by sterile carpet pieces. All specimens were cultured in SC and SCC culture media and fungal agents identification were based on macroscopic, microscopic characteristic and complement tests when it was necessary. Data analyzing was per­formed using SPSS version 13 for descriptive analyzing."nResults: A total of 593 samples were collected from different parts of pools. Interestingly in 13 samples from environ­mental places, dermatophytes were isolated as follows: Trichophyton mentagrophytes, T. rubrum, T. verrucosum and Epidermo­phyton floccosum 5, 4, 3 and 1 cases respectively. Ten cases of dermatophytes were isolated from floor of dressing area. Three hundred seventy two saprophytic fungi species and 32 yeasts were recovered from water and environment sur­faces samples. Aspergillus, Penicillium and Mucor were the most common isolated saprophytic fungi."nConclusion: Existence of saprophytic fungi and yeast in pools water seems to be an indicator of their resistance to detergent agents. In addition, yeast water contamination could be from swimmers. Dermatophytes isolation from pools environment ar­eas and foot washing sink, reveals the importance of public swimming pools in disease transmission. Because dressing places are being used by all of the swimmers, take care of hygienic discipline in these places should be noted by health pol­icy markers.

  18. Occurrence and simulation of trihalomethanes in swimming pool water: A simple prediction method based on DOC and mass balance.

    Science.gov (United States)

    Peng, Di; Saravia, Florencia; Abbt-Braun, Gudrun; Horn, Harald

    2016-01-01

    Trihalomethanes (THM) are the most typical disinfection by-products (DBPs) found in public swimming pool water. DBPs are produced when organic and inorganic matter in water reacts with chemical disinfectants. The irregular contribution of substances from pool visitors and long contact time with disinfectant make the forecast of THM in pool water a challenge. In this work occurrence of THM in a public indoor swimming pool was investigated and correlated with the dissolved organic carbon (DOC). Daily sampling of pool water for 26 days showed a positive correlation between DOC and THM with a time delay of about two days, while THM and DOC didn't directly correlate with the number of visitors. Based on the results and mass-balance in the pool water, a simple simulation model for estimating THM concentration in indoor swimming pool water was proposed. Formation of THM from DOC, volatilization into air and elimination by pool water treatment were included in the simulation. Formation ratio of THM gained from laboratory analysis using native pool water and information from field study in an indoor swimming pool reduced the uncertainty of the simulation. The simulation was validated by measurements in the swimming pool for 50 days. The simulated results were in good compliance with measured results. This work provides a useful and simple method for predicting THM concentration and its accumulation trend for long term in indoor swimming pool water.

  19. Seasonal dynamics of water and air chemistry in an indoor chlorinated swimming pool.

    Science.gov (United States)

    Zare Afifi, Mehrnaz; Blatchley, Ernest R

    2015-01-01

    Although swimming is known to be beneficial in terms of cardiovascular health, as well as for some forms of rehabilitation, swimming is also known to present risks to human health, largely in the form of exposure to microbial pathogens and disinfection byproducts (DBPs). Relatively little information is available in the literature to characterize the seasonal dynamics of air and water chemistry in indoor chlorinated swimming pools. To address this issue, water samples were collected five days per week from an indoor chlorinated swimming pool facility at a high school during the academic year and once per week during summer over a fourteen-month period. The samples were analyzed for free and combined chlorine, urea, volatile DBPs, pH, temperature and total alkalinity. Membrane Introduction Mass Spectrometry (MIMS) was used to identify and measure the concentrations of eleven aqueous-phase volatile DBPs. Variability in the concentrations of these DBPs was observed. Factors that influenced variability included bather loading and mixing by swimmers. These compounds have the ability to adversely affect water and air quality and human health. A large fraction of the existing literature regarding swimming pool air quality has focused on trichloramine (NCl₃). For this work, gas-phase NCl₃ was analyzed by an air sparging-DPD/KI method. The results showed that gas-phase NCl₃ concentration is influenced by bather loading and liquid-phase NCl₃ concentration. Urea is the dominant organic-N compound in human urine and sweat, and is known to be an important precursor for producing NCl₃ in swimming pools. Results of daily measurements of urea indicated a link between bather load and urea concentration in the pool.

  20. Detection of free living amoebae, Acanthamoeba and Naegleria, in swimming pools, Malaysia.

    Science.gov (United States)

    Init, I; Lau, Y L; Arin Fadzlun, A; Foead, A I; Neilson, R S; Nissapatorn, V

    2010-12-01

    This study reports the detection of Acanthamoeba and Naegleria species in 14 swimming pools around Petaling Jaya and Kuala Lumpur, Malaysia. Sampling was carried out at 4 sites (the platforms (P), wall (W), 1 meter from the wall (1) and middle (2)) of each swimming pool. These free living amoebae (FLA) were detected under light and inverted microscopes after being cultured on the surface of non-nutrient agar lawned with Escherichia coli. Acanthamoeba species were detected in higher number of culture plates from all sampling sites of all the swimming pools. While Naegleria, were detected in fewer culture plates at 3 sampling sites (absent at site P) of 8 swimming pools. This suggested that the thick double-walled cysts of Acanthamoeba were more resistant, thus remaining viable in the dry-hot areas of the platforms and in chlorinated water of the swimming pools whereas Naegleria cysts, that are fragile and susceptible to desiccation, preferred watery or moist areas for growth and proliferation. The prevalence of both FLA was highest at site W (76.2%), followed by site 1 (64.7%), lowest at site 2 (19.4%), and could be detected at all 3 sampling levels (top, middle and bottom) of these 3 sites. The surface of site W might act as a bio-film that accumulated all kinds of microbes providing sufficient requirement for the FLA to develop and undergo many rounds of life cycles as well as moving from top to bottom in order to graze food. Other factors such as human activities, the circulating system which was fixed at all swimming pools, blowing wind which might carry the cysts from surroundings and the swimming flagellate stage of Naegleria could also contribute to the distribution of the FLA at these sampling sites. Both FLA showed highest growth (80.4%) at room temperature (25-28 ºC) and lesser (70.0%) at 37 ºC which might be due to the overgrowth of other microbes (E. coli, fungi, algae, etc). While at 44 ºC, only Acanthamoeba species could survive thus showing that

  1. Cancer risk assessment from exposure to trihalomethanes in tap water and swimming pool water

    Institute of Scientific and Technical Information of China (English)

    PANYAKAPO Mallika; SOONTORNCHAI Sarisak; PAOPUREE Pongsri

    2008-01-01

    We investigated the concentration of trihalomethanes (THMs) in tap water and swimming pool water in the area of the Nakhon Path-om Municipality during the period April 2005-March 2006.The concentrations of total THMs,chloroform,bromodichloromethane,dibromochloromethane and bromoform in tap water were 12.70-41.74,6.72-29.19,1.12-11.75,0.63-3.55 and 0.08-3.40 μg/L,respectively,whereas those in swimming pool water were 26.15-65.09,9.50-36.97,8.90-18.01,5.19-22.78 and ND-6.56 μg/L,respectively.It implied that the concentration of THMs in swimming pool water was higher than those in tap water,particularly,brominated-THMs.Both tap water and swimming pool water contained concentrations of total THMs below the standards of the World Health Organization (WHO),European Union (EU) and the United States Environmental Protection Agency (USEPA) phase Ⅰ,but 1 out of 60 tap water samples and 60 out of 72 swimming pool water samples contained those over the Standard of the USEPA phase Ⅱ.From the two cases of cancer risk assessment including Case Ⅰ Non-Swimmer and Case Ⅱ Swimmer,assessment of cancer risk of non-swimmers from exposure to THMs at the highest and the average concentrations was 4.43×10-5 and 2.19×10-5,respectively,which can be classified as acceptable risk according to the Standard of USEPA.Assessment of cancer risk of swimmers from exposure to THMs at the highest and the average concentrations was 1.47×10-3 and 7.99×10-4,respectively,which can be classified as unacceptable risk and needs to be improved.Risk of THMs exposure from swimming was 93.9%-94.2% of the total risk.Cancer risk of THMs concluded from various routes in descending order was:skin exposure while swimming,gastro-intestinal exposure from tap water intake,and skin exposure to tap water and gastro-intestinal exposure while swimming.Cancer risk from skin exposure while swimming was 94.18% of the total cancer risk.

  2. Secondary formation of disinfection by-products by UV treatment of swimming pool water

    DEFF Research Database (Denmark)

    Spiliotopoulou, Aikaterini; Hansen, Kamilla Marie Speht; Andersen, Henrik Rasmus

    2015-01-01

    be replicated by performing the DBP formation assay with higher chlorine concentrations to simulate extended chlorination. Post-UV chlorination of water from a swimming pool that continuously uses UV treatment to control combined chlorine could not induce secondary formation for most DBPs. Concurrence...

  3. Swimming Pool Water Treatment Chemicals and/or Processes. Standard No. 22.

    Science.gov (United States)

    National Sanitation Foundation, Ann Arbor, MI.

    Chemicals or processes used or intended for use, in the treatment of swimming pool water are covered. Minimum public health limits or acceptability in regard to toxicity, biocidal effectiveness, and chemical behavior and analysis are presented. The appendices give guidelines to the scientific and statistically sound evaluations to determine the…

  4. Color Fringes Bordering Black Stripes at the Bottom of a Swimming Pool

    Science.gov (United States)

    Fuster, Gonzalo; Rojas, Roberto; Slüsarenko, Viktor

    2016-09-01

    We have observed a nice example of chromatic dispersion due to refraction in water, in the form of color fringes bordering the black stripes that exist at the bottom of a swimming pool. Here we give a qualitative description of the phenomenon, explaining the role of the black stripes and the dispersive index of refraction of water.

  5. Photolytic removal of DBPs by medium pressure UV in swimming pool water

    DEFF Research Database (Denmark)

    Hansen, Kamilla Marie Speht; Zortea, R.; Piketty, A.;

    2013-01-01

    Medium pressure UV is used for controlling the concentration of combined chlorine (chloramines) in many public swimming pools. Little is known about the fate of other disinfection by-products (DBPs) in UV treatment. Photolysis by medium pressure UV treatment was investigated for 12 DBPs reported ...

  6. Centrifugal Pumps for Swimming Pools. National Sanitation Foundation Standard Number 17.

    Science.gov (United States)

    National Sanitation Foundation, Ann Arbor, MI. Committee for Swimming Pool Equipment Standards.

    The pumps discussed herein are intended to be used for recirculating water in swimming pools, both public and private. Included are the basic components which may be a part of a pump such as the housing, strainer, impeller, valves, and such other parts as are attached or a part of the pump as supplied by the manufacturer. This standard is intended…

  7. "You Can Feel Them Looking at You": The Experiences of Adolescent Girls at Swimming Pools.

    Science.gov (United States)

    James, Kandy

    2000-01-01

    Explored constraints experienced by Australian high school girls when using public swimming pools, noting strategies they developed to negotiate these constraints. Data from focus groups and individual interviews indicated that embarrassment affected frequency and quality of participation. To reduce self-consciousness, some girls developed…

  8. Combined UV treatment and ozonation for the removal of by-product precursors in swimming pool water

    DEFF Research Database (Denmark)

    Cheema, Waqas Akram; Kaarsholm, Kamilla Marie Speht; Andersen, Henrik Rasmus

    2017-01-01

    Both UV treatment and ozonation are used to reduce different types of disinfection by-products (DBPs) in swimming pools. UV treatment is the most common approach, as it is particularly efficient at removing combined chlorine. However, the UV treatment of pool water increases chlorine reactivity...... and the formation of chloro-organic DBPs such as trihalomethanes. Based on the similar selective reactivity of ozone and chlorine, we hypothesised that the created reactivity to chlorine, as a result of the UV treatment of dissolved organic matter in swimming pool water, might also be expressed as increased...... for a new treatment method for swimming pools....

  9. Bioanalytical and chemical evaluation of disinfection by-products in swimming pool water.

    Science.gov (United States)

    Yeh, Ruby Y L; Farré, Maria José; Stalter, Daniel; Tang, Janet Y M; Molendijk, Jeffrey; Escher, Beate I

    2014-08-01

    Pool water disinfection is vital to prevent microbial pathogens. However, potentially hazardous disinfection by-products (DBP) are formed from the reaction between disinfectants and organic/inorganic precursors. The aim of this study was to evaluate the presence of DBPs in various swimming pool types in Brisbane, Australia, including outdoor, indoor and baby pools, and the dynamics after a complete water renewal. Chemical analysis of 36 regulated and commonly found DBPs and total adsorbable organic halogens as well as in vitro bioassays targeting cytotoxicity, oxidative stress and genotoxicity were used to evaluate swimming pool water quality. Dichloroacetic acid and trichloroacetic acid dominated in the pool water samples with higher levels (up to 2600 μg/L) than the health guideline values set by the Australian Drinking Water Guidelines (100 μg/L). Chlorinated DBPs occurred at higher concentrations compared to tap water, while brominated DBPs decreased gradually with increasing pool water age. Biological effects were expressed as chloroacetic acid equivalent concentrations and compared to predicted effects from chemical analysis and biological characterisation of haloacetic acids. The quantified haloacetic acids explained 35-118% of the absorbable organic halogens but less than 4% of the observed non-specific toxicity (cytotoxicity), and less than 1% of the observed oxidative stress response and genotoxicity. While the DBP concentrations in Australian pools found in this study are not likely to cause any adverse health effect, they are higher than in other countries and could be reduced by better hygiene of pool users, such as thorough showering prior to entering the pool and avoiding urination during swimming.

  10. An Investigation on Physicochemical and Microbial Water Quality of Swimming Pools in Yazd

    Directory of Open Access Journals (Sweden)

    M Dehvari

    2012-08-01

    Full Text Available Introduction: Disrespect of health regulations and proper disinfection of water and swimming pools is effective in incidence of health problems and transfer of infectious diseases to swimmers. The aim of this research was to investigate water of swimming pools in Yazd city and compare the results with national standards. Methods: In this study, 11 active covered swimming pools of Yazd city were sampled as census. Parameters of temperature, pH, amount of free and Combined chlorine residual, turbidity, alkalinity, hardness, the population of heterotrophic bacteria, Staphylococcus aureus, Pseudomonas aeruginosa, fecal streptococci, and fecal coliforms were studied. Sampling has been conducted every two weaks for 3 months and samples were analyzed under standard procedures. Results: In this research, amount of pH in 84.73%, free residual chlorine in 44.18%, Combined residual chlorine in 72.45%, alkalinity in19.82%, turbidity in 86.36%, hardness in 57.18% and temperature in 13.73% Samples were desirable. The fecal streptococci bacteria was not shown in all the swimming pools and population of heterotrophic bacteria, Staphylococcus aureus, Pseudomonas aeruginosa and fecal coliforms in 56.73%, 93.27%, 79.36% and 91.45% cases were desirable, respectively. Statistical analysis indicated that there is a direct relationship between Water turbidity and population of heterotraphic bacteria. Conclusion: According to the results, the parameters of heterotrophic bacteria population, also the alkalinity and temperature had the least compliant with the standards that shows the necessity for continuous monitoring of physical, chemical and microbial parameters and also control of filtration and disinfection of water condition of swimming pools.

  11. Photolytic removal of DBPs by medium pressure UV in swimming pool water.

    Science.gov (United States)

    Hansen, Kamilla M S; Zortea, Raissa; Piketty, Aurelia; Vega, Sergio Rodriguez; Andersen, Henrik Rasmus

    2013-01-15

    Medium pressure UV is used for controlling the concentration of combined chlorine (chloramines) in many public swimming pools. Little is known about the fate of other disinfection by-products (DBPs) in UV treatment. Photolysis by medium pressure UV treatment was investigated for 12 DBPs reported to be found in swimming pool water: chloroform, bromodichloromethane, dibromochloromethane, bromoform, dichloroacetonitrile, bromochloroacetonitrile, dibromoacetronitrile, trichloroacetonitrile, trichloronitromethane, dichloropropanone, trichloropropanone, and chloral hydrate. First order photolysis constants ranged 26-fold from 0.020 min(-1) for chloroform to 0.523 min(-1) for trichloronitromethane. The rate constants generally increased with bromine substitution. Using the UV removal of combined chlorine as an actinometer, the rate constants were recalculated to actual treatment doses of UV applied in a swimming pool. In an investigated public pool the UV dose was equivalent to an applied electrical energy of 1.34 kWh m(-3) d(-1) and the UV dose required to removed 90% of trichloronitromethane was 0.4 kWh m(-3) d(-1), while 2.6 kWh m(-3) d(-1) was required for chloral hydrate and the bromine containing haloacetonitriles and trihalomethanes ranged from 0.6 to 3.1 kWh m(-3) d(-1). It was predicted thus that a beneficial side-effect of applying UV for removing combined chlorine from the pool water could be a significant removal of trichloronitromethane, chloral hydrate and the bromine containing haloacetonitriles and trihalomethanes.

  12. Volatile disinfection byproducts resulting from chlorination of uric acid: implications for swimming pools.

    Science.gov (United States)

    Lian, Lushi; E, Yue; Li, Jing; Blatchley, Ernest R

    2014-03-18

    Cyanogen chloride (CNCl) and trichloramine (NCl3) are important disinfection byproducts in chlorinated swimming pools. However, some unknowns exist regarding the precursors of their formation. In this study, uric acid is shown to be an efficient precursor to formation of CNCl and NCl3. The molar yields of CNCl and NCl3 were observed to be as high as 44% (pH = 6.0, chlorine/precursor molar ratio [Cl/P] = 6.4) and 108% (pH = 7.0, Cl/P = 30), respectively, both being strong functions of Cl/P, pH, and temperature. Analysis of swimming pool water samples, combined with the results of experiments involving chlorination of uric acid, and chlorination of body fluid analog mixtures, indicated that uric acid chlorination may account for a large fraction of CNCl formation in swimming pools. Moreover, given that uric acid introduction to pools is attributable to urination, a voluntary action for most swimmers, these findings indicate important benefits to pool water and air chemistry that could result from improved hygiene habits on the part of swimmers.

  13. New halogenated disinfection byproducts in swimming pool water and their permeability across skin.

    Science.gov (United States)

    Xiao, Feng; Zhang, Xiangru; Zhai, Hongyan; Lo, Irene M C; Tipoe, George L; Yang, Mengting; Pan, Yang; Chen, Guanghao

    2012-07-01

    Chlorine is widely used for disinfecting public swimming pool water. The disinfectant chlorine, protecting swimmers from pathogenic infection in swimming, may be responsible for some adverse effects on swimmers' skin and health. In this study, numerous new halogenated disinfection byproducts (DBPs) in chlorinated pool water were detected with a powerful precursor ion scan method using electrospray ionization triple quadrupole mass spectrometry, with or without preseparation with ultra performance liquid chromatography. These new pool DBPs were demonstrated to be mainly halo(nitro)phenols, resulting from chlorination of human body substances (such as urine) in the presence of bromide. Among these new DBPs, 2,4-dibromophenol, 2,4-dichlorophenol, 2-bromophenol, 2,6-dibromo-4-nitrophenol, 2-bromo-6-chloro-4-nitrophenol, and 2,6-dichloro-4-nitrophenol were fully identified or confirmed. For 2,4-dibromophenol, 2,4-dichlorophenol and 2-bromophenol with pure standard compounds available, their permeability values across human skin were measured to be 0.031, 0.021, and 0.023 cm/h, respectively. The effects of chlorine on human skin were also investigated. The interaction of chlorine with epidermis was found to generate many new halogenated DBPs as well as common DBPs; the corneous layer was observed to become rough and even form larger pores after chlorine interaction. It is recommended that swimmers should avoid urinating in pools, and avoid prolonged swimming to reduce chlorine contact and prevent accelerated permeation of DBPs across skin.

  14. Convective cooling in a pool-type research reactor

    Science.gov (United States)

    Sipaun, Susan; Usman, Shoaib

    2016-01-01

    A reactor produces heat arising from fission reactions in the nuclear core. In the Missouri University of Science and Technology research reactor (MSTR), this heat is removed by natural convection where the coolant/moderator is demineralised water. Heat energy is transferred from the core into the coolant, and the heated water eventually evaporates from the open pool surface. A secondary cooling system was installed to actively remove excess heat arising from prolonged reactor operations. The nuclear core consists of uranium silicide aluminium dispersion fuel (U3Si2Al) in the form of rectangular plates. Gaps between the plates allow coolant to pass through and carry away heat. A study was carried out to map out heat flow as well as to predict the system's performance via STAR-CCM+ simulation. The core was approximated as porous media with porosity of 0.7027. The reactor is rated 200kW and total heat density is approximately 1.07+E7 Wm-3. An MSTR model consisting of 20% of MSTR's nuclear core in a third of the reactor pool was developed. At 35% pump capacity, the simulation results for the MSTR model showed that water is drawn out of the pool at a rate 1.28 kg s-1 from the 4" pipe, and predicted pool surface temperature not exceeding 30°C.

  15. Convective cooling in a pool-type research reactor

    Energy Technology Data Exchange (ETDEWEB)

    Sipaun, Susan, E-mail: susan@nm.gov.my [Malaysian Nuclear Agency, Industrial Technology Division, Blok 29T, Bangi 43200, Selangor (Malaysia); Usman, Shoaib, E-mail: usmans@mst.edu [Missouri University of Science and Technology, Nuclear Engineering, 222 Fulton Hall 301 W.14th St., Rolla 64509 MO (United States)

    2016-01-22

    A reactor produces heat arising from fission reactions in the nuclear core. In the Missouri University of Science and Technology research reactor (MSTR), this heat is removed by natural convection where the coolant/moderator is demineralised water. Heat energy is transferred from the core into the coolant, and the heated water eventually evaporates from the open pool surface. A secondary cooling system was installed to actively remove excess heat arising from prolonged reactor operations. The nuclear core consists of uranium silicide aluminium dispersion fuel (U{sub 3}Si{sub 2}Al) in the form of rectangular plates. Gaps between the plates allow coolant to pass through and carry away heat. A study was carried out to map out heat flow as well as to predict the system’s performance via STAR-CCM+ simulation. The core was approximated as porous media with porosity of 0.7027. The reactor is rated 200kW and total heat density is approximately 1.07+E7 Wm{sup −3}. An MSTR model consisting of 20% of MSTR’s nuclear core in a third of the reactor pool was developed. At 35% pump capacity, the simulation results for the MSTR model showed that water is drawn out of the pool at a rate 1.28 kg s{sup −1} from the 4” pipe, and predicted pool surface temperature not exceeding 30°C.

  16. Swimming Pools, Points indicating locations of public swimming pools in the City of Baltimore, MD, Published in 2008, 1:2400 (1in=200ft) scale, City of Baltimore.

    Data.gov (United States)

    NSGIC GIS Inventory (aka Ramona) — This Swimming Pools dataset, published at 1:2400 (1in=200ft) scale, was produced all or in part from Published Reports/Deeds information as of 2008. It is described...

  17. Swimming Pools, File name = RECREATION. Swimming pools are a portion of this dataset. http://www.harfordcountymd.gov/gis/Index.cfm, Published in 2007, 1:1200 (1in=100ft) scale, Harford County Government.

    Data.gov (United States)

    NSGIC GIS Inventory (aka Ramona) — This Swimming Pools dataset, published at 1:1200 (1in=100ft) scale, was produced all or in part from Orthoimagery information as of 2007. It is described as 'File...

  18. Outbreaks of Short-Incubation Ocular and Respiratory Illness Following Exposure to Indoor Swimming Pools

    Science.gov (United States)

    Bowen, Anna B.; Kile, James C.; Otto, Charles; Kazerouni, Neely; Austin, Connie; Blount, Benjamin C.; Wong, Hong-Nei; Beach, Michael J.; Fry, Alicia M.

    2007-01-01

    Objectives Chlorination destroys pathogens in swimming pool water, but by-products of chlorination can cause human illness. We investigated outbreaks of ocular and respiratory symptoms associated with chlorinated indoor swimming pools at two hotels. Measurements We interviewed registered guests and companions who stayed at hotels X and Y within 2 days of outbreak onset. We performed bivariate and stratified analyses, calculated relative risks (RR), and conducted environmental investigations of indoor pool areas. Results Of 77 guests at hotel X, 47 (61%) completed questionnaires. Among persons exposed to the indoor pool area, 22 (71%) of 31 developed ocular symptoms [RR = 24; 95% confidence interval (CI), 1.5–370], and 14 (45%) developed respiratory symptoms (RR = 6.8; 95% CI, 1.0–47) with a median duration of 10 hr (0.25–24 hr). We interviewed 30 (39%) of 77 registered persons and 59 unregistered companions at hotel Y. Among persons exposed to the indoor pool area, 41 (59%) of 69 developed ocular symptoms (RR = 24; 95% CI, 1.5–370), and 28 (41%) developed respiratory symptoms (RR = 17; 95% CI, 1.1–260) with a median duration of 2.5 hr (2 min–14 days). Four persons sought medical care. During the outbreak, the hotel X’s ventilation system malfunctioned. Appropriate water and air samples were not available for laboratory analysis. Conclusions and relevance to professional practice Indoor pool areas were associated with illness in these outbreaks. A large proportion of bathers were affected; symptoms were consistent with chloramine exposure and were sometimes severe. Improved staff training, pool maintenance, and pool area ventilation could prevent future outbreaks. PMID:17384776

  19. Material selection of safety-relevant components in indoor swimming pools

    Energy Technology Data Exchange (ETDEWEB)

    Faller, M.; Richner, P. [Swiss Federal Laboratories for Materials Testing and Research (EMPA), Ueberlandstrasse 129, CH-8600 Duebendorf (Switzerland)

    2003-05-01

    Suspended ceilings in indoor swimming pools are safety-relevant components. As was demonstrated by the collapses of the ceiling of the Uster (CH) indoor swimming pool (1985) and again at Steenwijk (NL, 2001) greater attention has to be paid to selecting suitable materials and inspecting the state of such components. Our findings according to corrosion of metal fastening components of more than 150 indoor swimming pools in Switzerland are reported. The corrosion behaviour of stainless steels and galvanized steels are compared and discussed including newer results from the literature. (Abstract Copyright [2003], Wiley Periodicals, Inc.) [German] Deckenabhaengungen in Hallenbaedern sind sicherheitsrelevante Bauteile. Der Wahl des geeigneten Werkstoffs und der Zustandskontrolle dieser Bauteile muessen - wie die Ereignisse des Deckeneinsturzes im Hallenbad Uster (CH, 1985) und erneut in Steenwijk (NL, 2001) zeigten - eine hohe Aufmerksamkeit gewidmet werden. Untersuchungsresultate in korrosionschemischer Hinsicht von metallischen Befestigungselementen in ueber 150 Hallenbaedern in der Schweiz werden vorgestellt. Das Korrosionsverhalten der nichtrostenden Staehle und verzinkter Staehle wird verglichen und unter Beruecksichtigung neuer Resultate aus der Literatur diskutiert. (Abstract Copyright [2003], Wiley Periodicals, Inc.)

  20. Prevalence and Antimicrobial-Resistance of Pseudomonas aeruginosa in Swimming Pools and Hot Tubs

    Directory of Open Access Journals (Sweden)

    Jonathan K. Lutz

    2011-02-01

    Full Text Available Pseudomonas aeruginosa is an important opportunistic pathogen in recreational waters and the primary cause of hot tub folliculitis and otitis externa. The aim of this surveillance study was to determine the background prevalence and antimicrobial resistance profile of P. aeruginosa in swimming pools and hot tubs. A convenience sample of 108 samples was obtained from three hot tubs and eight indoor swimming pools. Water and swab samples were processed using membrane filtration, followed by confirmation with polymerase chain reaction. Twenty-three samples (21% were positive for P. aeruginosa, and 23 isolates underwent susceptibility testing using the microdilution method. Resistance was noted to several antibiotic agents, including amikacin (intermediate, aztreonam, ceftriaxone, gentamicin, imipenem, meropenem (intermediate, ticarcillin/clavulanic acid, tobramycin (intermediate, and trimethoprim/sulfamethoxazole. The results of this surveillance study indicate that 96% of P. aeruginosa isolates tested from swimming pools and hot tubs were multidrug resistant. These results may have important implications for cystic fibrosis patients and other immune-suppressed individuals, for whom infection with multidrug-resistant P. aeruginosa would have greater impact. Our results underlie the importance of rigorous facility maintenance, and provide prevalence data on the occurrence of antimicrobial resistant strains of this important recreational water-associated and nosocomial pathogen.

  1. FEASIBILITY STUDY OF USING COMPLEX OF HYDROGEN PEROXIDE AND SILVER FOR DISINFECTING SWIMMING POOL WATER AND ITS ENVIRONMENT

    Directory of Open Access Journals (Sweden)

    R. Nabizadeh ، N. Samadi ، Z. Sadeghpour ، M. Beikzadeh

    2008-10-01

    Full Text Available In this research the application of Nanosil containing hydrogen peroxide and silver was studied in disinfecting swimming pool water and it's Environment. The effect of the disinfectant on Candida albicans (ATCC No. 10231, Aspergillus niger (ATCCNo. 16404, Pseudomonas aeruginosa (ATCC No. 9027, Serratia marcescens (PTCC No. 1111, Klebsiella pneumoniae (ATCC No. 10031 and Staphylococcus aureus (ATCC No. 29737 was evaluated. The main objective of this experiment was to determine the effective dose of Nanosil which could be used for disinfecting the environment of swimming pools and other surface area. Then, the effectiveness of Nanosil was studied in two private and one public swimming pools. Heterotrophic plate count, thermotolerant coliforms, Pseudomonas aeruginosa and Staphylococcus aureus were monitored as the target microorganisms in disinfection practice According to the result of this study, it is recommended to apply the Nanosil with the concentration of ≥3% (30000 mg/L for contact time of 30 min or more for practical disinfection in swimming pools environment. The application of Nanosil in real conditions of two private and one public swimming pools indicated that the acceptable microbial quality is also achievable if the disinfectant residual concentration would be as high as 20 mg/L in swimming pool water.

  2. Photolytic removal of DBPs by medium pressure UV in swimming pool water

    Energy Technology Data Exchange (ETDEWEB)

    Hansen, Kamilla M.S. [Department of Environmental Engineering, Technical University of Denmark (Denmark); Zortea, Raissa [Department of Land, Environment and Geotechnology Engineering, Polytechnic University of Turin (Italy); Piketty, Aurelia [Institute of Chemistry, Industrial and Chemical Engineering and Technology (INP-ENCIACET), National Polytechnic Institute of Toulouse (France); Vega, Sergio Rodriguez [Chemical Engineering, Complutense University of Madrid (Spain); Andersen, Henrik Rasmus, E-mail: Henrik@ndersen.net [Department of Environmental Engineering, Technical University of Denmark (Denmark)

    2013-01-15

    Medium pressure UV is used for controlling the concentration of combined chlorine (chloramines) in many public swimming pools. Little is known about the fate of other disinfection by-products (DBPs) in UV treatment. Photolysis by medium pressure UV treatment was investigated for 12 DBPs reported to be found in swimming pool water: chloroform, bromodichloromethane, dibromochloromethane, bromoform, dichloroacetonitrile, bromochloroacetonitrile, dibromoacetronitrile, trichloroacetonitrile, trichloronitromethane, dichloropropanone, trichloropropanone, and chloral hydrate. First order photolysis constants ranged 26-fold from 0.020 min{sup −1} for chloroform to 0.523 min{sup −1} for trichloronitromethane. The rate constants generally increased with bromine substitution. Using the UV removal of combined chlorine as an actinometer, the rate constants were recalculated to actual treatment doses of UV applied in a swimming pool. In an investigated public pool the UV dose was equivalent to an applied electrical energy of 1.34 kWh m{sup −3} d{sup −1} and the UV dose required to removed 90% of trichloronitromethane was 0.4 kWh m{sup −3} d{sup −1}, while 2.6 kWh m{sup −3} d{sup −1} was required for chloral hydrate and the bromine containing haloacetonitriles and trihalomethanes ranged from 0.6 to 3.1 kWh m{sup −3} d{sup −1}. It was predicted thus that a beneficial side-effect of applying UV for removing combined chlorine from the pool water could be a significant removal of trichloronitromethane, chloral hydrate and the bromine containing haloacetonitriles and trihalomethanes. - Highlights: ► UV irradiation is able to degrade all 12 investigated disinfection by-products. ► Bromine species are easier to remove than their chlorinated analogues. ► UV dose used for combined chlorine was comparable with doses required for DBP removal. ► Significant removal of some disinfection by-products in swimming pools is indicated.

  3. Mapping Neglected Swimming Pools from Satellite Data for Urban Vector Control

    Science.gov (United States)

    Barker, C. M.; Melton, F. S.; Reisen, W. K.

    2010-12-01

    Neglected swimming pools provide suitable breeding habit for mosquitoes, can contain thousands of mosquito larvae, and present both a significant nuisance and public health risk due to their inherent proximity to urban and suburban populations. The rapid increase and sustained rate of foreclosures in California associated with the recent recession presents a challenge for vector control districts seeking to identify, treat, and monitor neglected pools. Commercial high resolution satellite imagery offers some promise for mapping potential neglected pools, and for mapping pools for which routine maintenance has been reestablished. We present progress on unsupervised classification techniques for mapping both neglected pools and clean pools using high resolution commercial satellite data and discuss the potential uses and limitations of this data source in support of vector control efforts. An unsupervised classification scheme that utilizes image segmentation, band thresholds, and a change detection approach was implemented for sample regions in Coachella Valley, CA and the greater Los Angeles area. Comparison with field data collected by vector control personal was used to assess the accuracy of the estimates. The results suggest that the current system may provide some utility for early detection, or cost effective and time efficient annual monitoring, but additional work is required to address spectral and spatial limitations of current commercial satellite sensors for this purpose.

  4. Effect of selection of pH in swimming pool on formation of chlorination by-products

    DEFF Research Database (Denmark)

    Hansen, Kamilla Marie Speht; Willach, Sarah; Mosbæk, Hans;

    2011-01-01

    Chlorine is used as disinfection agent in public swimming pools, but also reacts with organic matter in the water forming chlorinat ed disinfection by-products. In order to evaluate the effect of choice of pHsetpoint in the pool we investigated the effect of chlorination of artificial body fluid...

  5. Biologically active carbon filtration for haloacetic acid removal from swimming pool water.

    Science.gov (United States)

    Tang, Hao L; Xie, Yuefeng F

    2016-01-15

    A biologically activate carbon (BAC) filter was continuously operated on site for the treatment of haloacetic acids (HAAs) in an outdoor swimming pool at an average empty bed contact time (EBCT) of 5.8 min. Results showed that BAC filtration was a viable technology for direct removal of HAAs from the pool water with a nominal efficiency of 57.7% by the filter while the chlorine residuals were 1.71 ± 0.90 mg/L during the study. THMs and TOC were not removed and thus were not considered as indicators of the effectiveness of BAC filtration. Increased EBCT in the range of 4.5 and 6.4 min led to improved HAA removal performance, which could be best fit by a logarithmic regression model. BAC filtration also affected the HAA speciation by removing more dichloroacetic acid (DCAA) than trichloroacetic acid (TCAA), resulting in a lower ratio of DCAA/TCAA in the filtered effluent. However, the observation of an overall constant ratio could be attributable to a complex formation and degradation mechanism occurring in swimming pools.

  6. Photolysis of inorganic chloramines and efficiency of trichloramine abatement by UV treatment of swimming pool water.

    Science.gov (United States)

    Soltermann, Fabian; Widler, Tobias; Canonica, Silvio; von Gunten, Urs

    2014-06-01

    Trichloramine, one of the three inorganic chloramines (mono-, di- and trichloramine), is a problematic disinfection by-product in recreational pool water since it causes skin and eye irritations as well as irritations of the respiratory tract. The most commonly used chloramine mitigation strategy in pool water is UV treatment. Experiments with membrane inlet mass spectrometry (MIMS) confirmed that inorganic chloramines are effectively degraded by UV irradiation with low-pressure (LP) and medium-pressure (MP) mercury lamps (apparent quantum yields (QY): NH2Cl = 0.50 (LP) and 0.31 (MP) mol einstein(-1), NHCl2: 1.06 (LP) and 0.85 (MP) mol einstein(-1)). Trichloramine showed the fastest depletion with a quantum yield slightly above 2 mol einstein(-1) in purified (LP and MP) and pool water (MP). This high quantum yield can partly be explained by reactions involving OH radicals (purified water) and the reaction of trichloramine with moieties formed during UV irradiation of pool water. The presence of free chlorine affects trichloramine degradation (QY: ∼1.5 mol einstein(-1)) since it scavenges OH radicals and competes with trichloramine for reactive species (e.g. organic amines). Measurements in a pool facility revealed that the installed UV reactors degraded trichloramine by 40-50% as expected from laboratory experiments. However, trichloramine reduction in the pools was less pronounced than in the UV reactors. Model calculations combining pool hydraulics with formation/abatement of trichloramine showed that there was a fast trichloramine formation in the pool from the residual chlorine and nitrogenous precursors. The main factors influencing trichloramine concentrations in pool water are the free chlorine concentration and the UV treatment in combination with the recirculation rate through the water treatment system.

  7. Solar swimming pool heating plants self-constructed with ribbed pipes

    Energy Technology Data Exchange (ETDEWEB)

    Pfenning, R.

    The solar absorber suitable for self-construction consists of ribbed pipes which can be joined together to units of any size with the help of simple plug connections. By using especially developed ribbed pipes for absorbing the insolation an increased surface and, moreover, a greater stability can be achieved. The material used for the ribbed pipes is a special polypropylene which is UV stable and resistant against all chemicals occurring in swimming pool water. The same is valid for the rubber parts of the plug connections which are made of EPDM.

  8. Pseudomonas aeruginosa in Swimming Pool Water: Evidences and Perspectives for a New Control Strategy

    Directory of Open Access Journals (Sweden)

    Marco Guida

    2016-09-01

    Full Text Available Pseudomonas aeruginosa is frequently isolated in swimming pool settings. Nine recreational and rehabilitative swimming pools were monitored according to the local legislation. The presence of P. aeruginosa was correlated to chlorine concentration. The ability of the isolates to form a biofilm on plastic materials was also investigated. In 59.5% of the samples, microbial contamination exceeded the threshold values. P. aeruginosa was isolated in 50.8% of these samples. The presence of P. aeruginosa was not correlated with free or total chlorine amount (R2 < 0.1. All the isolates were moderate- to strong-forming biofilm (Optical Density O.D.570 range 0.7–1.2. To control biofilm formation and P. aeruginosa colonization, Quantum FreeBioEnergy© (QFBE, FreeBioEnergy, Brisighella, Italy, has been applied with encouraging preliminary results. It is a new, promising control strategy based on the change of an electromagnetic field which is responsible for the proliferation of some microorganisms involved in biofilm formation, such as P. aeruginosa.

  9. Isolation and identification of Acanthamoeba spp. from thermal swimming pools and spas in Southern Brazil.

    Science.gov (United States)

    Fabres, Laura Fuhrich; Rosa Dos Santos, Sayonara Peixoto; Benitez, Lisianne Brittes; Rott, Marilise Brittes

    2016-03-01

    Free-living amoebae (FLA) are widely distributed in soil and water. A few number of them are implicated in human disease: Acanthamoeba spp., Naegleria fowleri, Balamuthia mandrillaris and Sappinia diploidea. Species of Acanthamoeba can cause keratitis and brain infections. In this study, 72 water samples were taken from both hot tubs and thermal swimming pools in the city of Porto Alegre, RS, Brazil, to determine the presence of Acanthamoeba in the water as well as perform the phenotypic and genotypic characterization of the isolates. The identification of the isolates was based on the cysts morphology and PCR amplification using genus-specific oligonucleotides. When the isolates were submitted to PCR reaction only 8 were confirmed as belonging to the genus Acanthamoeba. The sequences analysis when compared to the sequences in the GenBank, showed genotype distribution in group T3 (12,5%), T5 (12,5%), T4 (25%) and T15 (50%). The results of this study confirmed the presence of potentially pathogenic isolates of free living amoebae in hot swimming pool and spas which can present risks to human health.

  10. Decommissioning of the pool reactor Thetis in Ghent, Belgium

    Energy Technology Data Exchange (ETDEWEB)

    Cortenbosch, Geert; Mommaert, Chantal [Bel V, Brussels (Belgium); Tierens, Hubert; Monsieurs, Myriam; Meierlaen, Isabelle; Strijckmans, Karel [Ghent Univ. (Belgium)

    2016-11-15

    The Thetis research pool reactor (with a nominal power of 150 kW) of the Ghent University was operational from 1967 till December 2003. The first phase of the decommissioning of the reactor, the removal of the spent fuel from the site, took place in 2010. The cumulative dose received was only 404 man . μSv. During the second phase, the transition period between the removal of the spent fuel in 2010 and the start of the decommissioning phase in March 2013, 3-monthly internal inspections and inspections by Bel V, were performed. The third and final decommissioning phase started on March 18, 2013. The total dose received between March 2013 and August 2013 was 1561 man . μSv. The declassification from a Class I installation to a Class II installation was possible by the end of 2015. The activated concrete in the reactor pool will remain under regulatory control until the activation levels are lower than the limits for free release.

  11. What's in the pool? A comprehensive identification of disinfection by-products and assessment of mutagenicity of chlorinated and brominated swimming pool water

    NARCIS (Netherlands)

    Richardson, S.D.; Demarini, D.M.; Kogevinas, M.; Fernandez, P.; Marco, E.; Lourencetti, C.; Balleste, C.; Heederik, D.; Meliefste, K.; McKague, A.B.; Marcos, R.; Font-Ribera, L.; Grimalt, J.O.; Villanueva, C.M.

    2010-01-01

    BACKGROUND: Swimming pool disinfectants and disinfection by-products (DBPs) have been linked to human health effects, including asthma and bladder cancer, but no studies have provided a comprehensive identification of DBPs in the water and related that to mutagenicity. OBJECTIVES: We performed a com

  12. Secondary formation of disinfection by-products by UV treatment of swimming pool water.

    Science.gov (United States)

    Spiliotopoulou, Aikaterini; Hansen, Kamilla M S; Andersen, Henrik R

    2015-07-01

    Formation of disinfection by-products (DBPs) during experimental UV treatment of pool water has previously been reported with little concurrence between laboratory studies, field studies and research groups. In the current study, changes in concentration of seven out of eleven investigated volatile DBPs were observed in experiments using medium pressure UV treatment, with and without chlorine and after post-UV chlorination. Results showed that post-UV chlorine consumption increased, dose-dependently, with UV treatment dose. A clear absence of trihalomethane formation by UV and UV with chlorine was observed, while small yet statistically significant increases in dichloroacetonitrile and dichloropropanone concentrations were detected. Results indicate that post-UV chlorination clearly induced secondary formation of several DBPs. However, the formation of total trihalomethanes was no greater than what could be replicated by performing the DBP formation assay with higher chlorine concentrations to simulate extended chlorination. Post-UV chlorination of water from a swimming pool that continuously uses UV treatment to control combined chlorine could not induce secondary formation for most DBPs. Concurrence for induction of trihalomethanes was identified between post-UV chlorination treatments and simulated extended chlorination time treatment. Trihalomethanes could not be induced by UV treatment of water from a continuously UV treated pool. This indicates that literature reports of experimentally induced trihalomethane formation by UV may be a result of kinetic increase in formation by UV. However, this does not imply that higher trihalomethane concentrations would occur in pools that apply continuous UV treatment. The bromine fraction of halogens in formed trihalomethanes increased with UV dose. This indicates that UV removes bromine atoms from larger molecules that participate in trihalomethane production during post-UV chlorination. Additionally, no significant

  13. Heated indoor swimming pools, infants, and the pathogenesis of adolescent idiopathic scoliosis: a neurogenic hypothesis

    Directory of Open Access Journals (Sweden)

    McMaster Marianne E

    2011-10-01

    Full Text Available Abstract Background In a case-control study a statistically significant association was recorded between the introduction of infants to heated indoor swimming pools and the development of adolescent idiopathic scoliosis (AIS. In this paper, a neurogenic hypothesis is formulated to explain how toxins produced by chlorine in such pools may act deleteriously on the infant's immature central nervous system, comprising brain and spinal cord, to produce the deformity of AIS. Presentation of the hypothesis Through vulnerability of the developing central nervous system to circulating toxins, and because of delayed epigenetic effects, the trunk deformity of AIS does not become evident until adolescence. In mature healthy swimmers using such pools, the circulating neurotoxins detected are chloroform, bromodichloromethane, dibromochloromethane, and bromoform. Cyanogen chloride and dichloroacetonitrile have also been detected. Testing the hypothesis In infants, the putative portals of entry to the blood could be dermal, oral, or respiratory; and entry of such circulating small molecules to the brain are via the blood-brain barrier, blood-cerebrospinal fluid barrier, and circumventricular organs. Barrier mechanisms of the developing brain differ from those of adult brain and have been linked to brain development. During the first 6 months of life cerebrospinal fluid contains higher concentrations of specific proteins relative to plasma, attributed to mechanisms continued from fetal brain development rather than immaturity. Implications of the hypothesis The hypothesis can be tested. If confirmed, there is potential to prevent some children from developing AIS.

  14. Characterization of a virulent Leptospira interrogans strain isolated from an abandoned swimming pool.

    Science.gov (United States)

    Forster, Karine M; Hartwig, Daiane D; Seixas, Fabiana K; McBride, Alan J A; Monte, Leonardo G; Recuero, Ana Lúcia C; Brod, Claudiomar S; Hartleben, Cláudia P; Amaral, Marta; Dellagostin, Odir A

    2013-01-01

    Pathogenic Leptospira spp. are the etiological agents of leptospirosis, an important disease of both humans and animals. In urban settings, L. interrogans serovars are the predominant cause of disease in humans. The purpose of this study was to characterize a novel Leptospira isolate recovered from an abandoned swimming pool. Molecular characterization through sequencing of the rpoB gene revealed 100% identity with L. interrogans and variable-number tandem-repeat (VNTR) analysis resulted in a banding pattern identical to L. interrogans serogroup Icterohaemorrhagiae, serovar Copenhageni or Icterohaemorrhagiae. The virulence of the strain was determined in a hamster model of lethal leptospirosis. The lethal dose 50% (LD50) was calculated to be two leptospires in female hamsters and a histopathological examination of infected animals found typical lesions associated with severe leptospirosis, including renal epithelium degeneration, hepatic karyomegaly, liver-plate disarray and lymphocyte infiltration. This highly virulent strain is now available for use in further studies, especially evaluation of vaccine candidates.

  15. Should children be SCUBA diving?: Cerebral arterial gas embolism in a swimming pool.

    Science.gov (United States)

    Johnson, Valerie; Adkinson, Cheryl; Bowen, Mariya; Ortega, Henry

    2012-04-01

    Cerebral arterial gas embolism (CAGE) is a well-known serious complication of self-contained breathing apparatus (SCUBA) diving. Most serious complications of SCUBA diving occur in adults because most of SCUBA divers are adults. However, young age is an independent risk factor for injury in SCUBA diving and shallow-water SCUBA diving is the riskiest environment for CAGE. We present a case of a 10-year-old boy who developed CAGE while taking SCUBA diving lessons in a university swimming pool. This case illustrates the potential danger of SCUBA diving for children who lack understanding of the physics of diving as well as the often unappreciated risk of shallow-water SCUBA diving. Our intent is to educate providers of primary care to children, so that they may appropriately advise parents about SCUBA diving, and to educate providers of emergency care to children, so that they will recognize this uncommon but serious emergency condition.

  16. Secondary formation of disinfection by-products by UV treatment of swimming pool water

    Energy Technology Data Exchange (ETDEWEB)

    Spiliotopoulou, Aikaterini [Water ApS, Farum Gydevej 64, 3520 Farum (Denmark); Department of Environmental Engineering, Technical University of Denmark, Miljøvej, Building 113, 2800 Kongens Lyngby (Denmark); Hansen, Kamilla M.S., E-mail: kmsh@env.dtu.dk [Department of Environmental Engineering, Technical University of Denmark, Miljøvej, Building 113, 2800 Kongens Lyngby (Denmark); Andersen, Henrik R. [Department of Environmental Engineering, Technical University of Denmark, Miljøvej, Building 113, 2800 Kongens Lyngby (Denmark)

    2015-07-01

    Formation of disinfection by-products (DBPs) during experimental UV treatment of pool water has previously been reported with little concurrence between laboratory studies, field studies and research groups. In the current study, changes in concentration of seven out of eleven investigated volatile DBPs were observed in experiments using medium pressure UV treatment, with and without chlorine and after post-UV chlorination. Results showed that post-UV chlorine consumption increased, dose-dependently, with UV treatment dose. A clear absence of trihalomethane formation by UV and UV with chlorine was observed, while small yet statistically significant increases in dichloroacetonitrile and dichloropropanone concentrations were detected. Results indicate that post-UV chlorination clearly induced secondary formation of several DBPs. However, the formation of total trihalomethanes was no greater than what could be replicated by performing the DBP formation assay with higher chlorine concentrations to simulate extended chlorination. Post-UV chlorination of water from a swimming pool that continuously uses UV treatment to control combined chlorine could not induce secondary formation for most DBPs. Concurrence for induction of trihalomethanes was identified between post-UV chlorination treatments and simulated extended chlorination time treatment. Trihalomethanes could not be induced by UV treatment of water from a continuously UV treated pool. This indicates that literature reports of experimentally induced trihalomethane formation by UV may be a result of kinetic increase in formation by UV. However, this does not imply that higher trihalomethane concentrations would occur in pools that apply continuous UV treatment. The bromine fraction of halogens in formed trihalomethanes increased with UV dose. This indicates that UV removes bromine atoms from larger molecules that participate in trihalomethane production during post-UV chlorination. Additionally, no significant

  17. Cervical spine injuries resulting from diving accidents in swimming pools: outcome of 34 patients.

    Science.gov (United States)

    Borius, Pierre-Yves; Gouader, Ismail; Bousquet, Philippe; Draper, Louisa; Roux, Franck-Emmanuel

    2010-04-01

    Cervical spine injuries after diving into private swimming pools can lead to dramatic consequences. We reviewed 34 patients hospitalized in our center between 1996 and 2006. Data was collected from their initial admission and from follow-up appointments. The injuries were sustained by young men in 97% (mean age 27) and the majority happened during the summer (88%). Fractures were at C5-C7 in 70%. American Spinal Injury Association class (ASIA) on admission was A for 8 patients, B for 4, C for 4, D for 1, and E for 17. There were 23 surgical spine stabilizations. Final ASIA class was A for 6 patients, B for 1, C for 3, D for 5, and E for 18. The mean duration of hospitalization was 21.3 days in our neurosurgical center (mean overall cost: 36,000 Euros/patient) plus 10.6 months in rehabilitation center for the 15 patients admitted who had an ASIA class A to C. Mean overall direct cost for a patient with class A is almost 300,000 Euros, compared to around 10,000 Euros for patients with class D and E. In addition, a profound impact on personal and professional life was seen in many cases including 11 divorces and 7 job losses. Dangerous diving into swimming pools can result in spinal injuries with drastic consequences, including permanent physical disability and a profound impact on socio-professional status. Moreover, there are significant financial costs to society. Better prevention strategies should be implemented to reduce the impact of this public health problem.

  18. Sleeping Beauty. Revitalisation of the old indoor swimming pool Heidelberg; Sleeping Beauty. Revitalisierung des alten Hallenbads Heidelberg

    Energy Technology Data Exchange (ETDEWEB)

    Paul, Jochen

    2010-07-01

    Since its closure before nearly 30 years due to safety aspects, the monument protected indoor swimming pool in Heidelberg (Federal Republic of Germany) dilapidated appreciably. Only after moving away of the local council from its demand of the wet use, an investor could be found.

  19. Natural and mixed convection in the cylindrical pool of TRIGA reactor

    Science.gov (United States)

    Henry, R.; Tiselj, I.; Matkovič, M.

    2017-02-01

    Temperature fields within the pool of the JSI TRIGA MARK II nuclear research reactor were measured to collect data for validation of the thermal hydraulics computational model of the reactor tank. In this context temperature of the coolant was measured simultaneously at sixty different positions within the pool during steady state operation and two transients. The obtained data revealed local peculiarities of the cooling water dynamics inside the pool and were used to estimate the coolant bulk velocity above the reactor core. Mixed natural and forced convection in the pool were simulated with a Computational Fluid Dynamics code. A relatively simple CFD model based on Unsteady RANS turbulence model was found to be sufficient for accurate prediction of the temperature fields in the pool during the reactor operation. Our results show that the simple geometry of the TRIGA pool reactor makes it a suitable candidate for a simple natural circulation benchmark in cylindrical geometry.

  20. Protocol of actuation before occurrence of 'molluscum contagiosum' for use in public swimming pools

    Directory of Open Access Journals (Sweden)

    Juan Francisco Sánchez Pérez

    2008-12-01

    Full Text Available The main objective is to develop a protocol for the disinfection of episodes of Molluscum contagiosum and establish an objective indicator. Molluscum contagiosum is a virus of Poxviridae Family. This virus produces a common infection in children that occurs when they come into direct contact with a lesion or with contaminated objects. In November 2008 is received at the Servicio de Sanidad Ambiental (Dirección General de Salud Pública, Consejería de Sanidad y Consumo, Comunidad Autónoma de la Región de Murcia a telephone call from the Epidemiology Service, which reported the existence of about 12-15 cases of children affected by Molluscum contagiosum. In addition, they indicated us that the suspicions fell on the Municipal Pool Cover Alhama de Murcia. Immediately we contacted the responsible staff and we send them a protocol developed with information from several sources. The analysis of articles used for water activities showed absence of Molluscum contagiosum. We selected "absence of molds and yeasts” as indicator. All this coincided with the disappearance of the cases. Months later, in March 2009 we detected new cases of children affected in another pool in the town of Alcantarilla. Due to the success of the methodology used in the earlier incident we performed the same actions and we obtained the same results. The protocol developed by this Service is effective to avoid the occurrence of more cases. We propose the “absence of molds and yeasts” as an indicator to evaluate the presence of Molluscum contagiosum. Coinciding with the update of the rules of public swimming pools in our Region we have introduced an article that indicates that the objects used for water activities must be disinfected after each use.

  1. [Free-living amoebae in the Grenoble area swimming pool water. Influence of th "winter-summer" use and of the sterilising procedure (author's transl)].

    Science.gov (United States)

    Grillot, R; Ambroise-Thomas, P

    1980-01-01

    An epidemiological study concerning the search for and identification of free-living amoebae has been carried out on swimming pool water in the Grenoble area. Eleven establishments were surveyed over a period of one year, by taking samples of water every month. The results obtained show that the positive nature of the samples and the nature of the isolated species are influenced by the two factors being studied: The rhythm of the "Summer-Winter" use of swimming pools and the nature of the sterilising procedure, chlorine, bromine and ozone. The current sterilising conditions of the swimming pool water are discussed.

  2. Prevalence of Ocular, Respiratory and Cutaneous Symptoms in Indoor Swimming Pool Workers and Exposure to Disinfection By-Products (DBPs

    Directory of Open Access Journals (Sweden)

    Guglielmina Fantuzzi

    2010-03-01

    Full Text Available The objective of this cross-sectional study was to investigate the prevalence of self-reported respiratory, ocular and cutaneous symptoms in subjects working at indoor swimming pools and to assess the relationship between frequency of declared symptoms and occupational exposure to disinfection by-products (DBPs. Twenty indoor swimming pools in the Emilia Romagna region of Italy were included in the study. Information about the health status of 133 employees was collected using a self-administered questionnaire. Subjects working at swimming pools claimed to frequently experience the following symptoms: cold (65.4%, sneezing (52.6%, red eyes (48.9% and itchy eyes (44.4%. Only 7.5% claimed to suffer from asthma. Red eyes, runny nose, voice loss and cold symptoms were declared more frequently by pool attendants (lifeguards and trainers when compared with employees working in other areas of the facility (office, cafe, etc.. Pool attendants experienced generally more verrucas, mycosis, eczema and rash than others workers; however, only the difference in the frequency of self-declared mycosis was statistically significant (p = 0.010. Exposure to DBPs was evaluated using both environmental and biological monitoring. Trihalomethanes (THMs, the main DBPs, were evaluated in alveolar air samples collected from subjects. Swimming pool workers experienced different THM exposure levels: lifeguards and trainers showed the highest mean values of THMs in alveolar air samples (28.5 ± 20.2 µg/m3, while subjects working in cafe areas (17.6 ± 12.1 µg/m3, offices (14.4 ± 12.0 µg/m3 and engine rooms (13.6 ± 4.4 µg/m3 showed lower exposure levels. Employees with THM alveolar air values higher than 21 µg/m3 (median value experienced higher risks for red eyes (OR 6.2; 95% CI 2.6–14.9, itchy eyes (OR 3.5; 95% CI 1.5–8.0, dyspnea/asthma (OR 5.1; 95% CI 1.0–27.2 and blocked nose (OR 2.2; 95% CI 1.0–4.7 than subjects with less exposure. This study confirms

  3. Characterization of a virulent Leptospira interrogans strain isolated from an abandoned swimming pool

    Directory of Open Access Journals (Sweden)

    Karine M. Forster

    2013-01-01

    Full Text Available Pathogenic Leptospira spp. are the etiological agents of leptospirosis, an important disease of both humans and animals. In urban settings, L. interrogans serovars are the predominant cause of disease in humans. The purpose of this study was to characterize a novel Leptospira isolate recovered from an abandoned swimming pool. Molecular characterization through sequencing of the rpoB gene revealed 100% identity with L. interrogans and variable-number tandem-repeat (VNTR analysis resulted in a banding pattern identical to L. interrogans serogroup Icterohaemorrhagiae, serovar Copenhageni or Icterohaemorrhagiae. The virulence of the strain was determined in a hamster model of lethal leptospirosis. The lethal dose 50% (LD50 was calculated to be two leptospires in female hamsters and a histopathological examination of infected animals found typical lesions associated with severe leptospirosis, including renal epithelium degeneration, hepatic karyomegaly, liver-plate disarray and lymphocyte infiltration. This highly virulent strain is now available for use in further studies, especially evaluation of vaccine candidates.

  4. Detection and quantification of human adenovirus genomes in Acanthamoeba isolated from swimming pools

    Directory of Open Access Journals (Sweden)

    RODRIGO STAGGEMEIER

    2016-01-01

    Full Text Available ABSTRACT Acanthamoeba is the most common free-living environmental amoeba, it may serve as an important vehicle for various microorganisms living in the same environment, such as viruses, being pathogenic to humans. This study aimed to detect and quantify human adenoviruses (HAdV in Acanthamoebas isolated from water samples collected from swimming pools in the city of Porto Alegre, Southern Brazil. Free-living amoebae of the genus Acanthamoeba were isolated from water samples, and isolates (n=16 were used to investigate the occurrence of HAdVs. HAdV detection was performed by quantitative real-time polymerase chain reaction (qPCR. HAdVs were detected in 62.5% (10/16 of Acanthamoeba isolates, ranging from 3.24x103 to 5.14x105 DNA copies per milliliter of isolate. HAdV viral loads found in this study are not negligible, especially because HAdV infections are associated with several human diseases, including gastroenteritis, respiratory distress, and ocular diseases. These findings reinforce the concept that Acanthamoeba may act as a reservoir and promote HAdV transmission through water.

  5. Preliminary Requirement of Hot Pool Free Surface Level from PGSFR Reactor Head

    Energy Technology Data Exchange (ETDEWEB)

    Koo, Gyeonghoi; Joo, Hyeongkook [Korea Atomic Energy Research Institute, Daejeon (Korea, Republic of)

    2014-05-15

    The sensitivity study on structural integrity evaluations are carried out to make a decision of a hot pool free surface location from the reactor head for a preliminary designed reactor enclosure system. To do this, the thermal stress evaluations for a reactor vessel are carried out for a steady state normal operating condition with detailed heat transfer analyses through the reactor enclosure system. From these results, the preliminary design requirement of a hot pool free surface location from the reactor head is established to be 2.0m. From the sensitivity studies on the structural integrity evaluations for a steady state condition, the preliminary distance from the hot pool free surface to the reactor head is determined to be 2.0m same as a conceptual design. More detailed structural analyses for a reactor enclosure system will be carried out as a PGSFR structural design goes forward in detail.

  6. Swimming Pools, Published in 2010, 1:1200 (1in=100ft) scale, Salisbury Wicomico County Department of Planning, Zoning & Community Development.

    Data.gov (United States)

    NSGIC GIS Inventory (aka Ramona) — This Swimming Pools dataset, published at 1:1200 (1in=100ft) scale, was produced all or in part from Orthoimagery information as of 2010. Data by this publisher are...

  7. Swimming Pools, Part of our City of Hutchinson polygon building footprint layer, Published in 2006, 1:600 (1in=50ft) scale, City of Hutchinson.

    Data.gov (United States)

    NSGIC GIS Inventory (aka Ramona) — This Swimming Pools dataset, published at 1:600 (1in=50ft) scale, was produced all or in part from Orthoimagery information as of 2006. It is described as 'Part of...

  8. ‘Right now, Sophie *swims in the pool?!’: Brain potentials of grammatical aspect processing

    Directory of Open Access Journals (Sweden)

    Monique eFlecken

    2015-11-01

    Full Text Available We investigated whether brain potentials of grammatical aspect processing resemble semantic or morpho-syntactic processing, or whether they instead are characterized by an entirely distinct pattern in the same individuals. We studied aspect from the perspective of agreement between the temporal information in the context (temporal adverbials, e.g., Right now and a morpho-syntactic marker of grammatical aspect (e.g., progressive is swimming. Participants read questions providing a temporal context that was progressive (What is Sophie doing in the pool right now? or habitual (What does Sophie do in the pool every Monday?. Following a lead-in sentence context such as Right now, Sophie…, we measured ERPs time-locked to verb phrases in four different conditions, e.g., (a is swimming (control; (b *is cooking (semantic violation; (c *are swimming (morpho-syntactic violation; or (d?swims (aspect mismatch; …in the pool. The collected ERPs show typical N400 and P600 effects for semantics and morpho-syntax, while aspect processing elicited an Early Negativity (250-350 ms. The aspect-related Negativity was short-lived and had a central scalp distribution with an anterior onset. This differentiates it not only from the semantic N400 effect, but also from the typical (LAN (Left Anterior Negativity, that is frequently reported for various types of agreement processing. Moreover, aspect processing was not accompanied by a clear P600 modulation.We argue that the specific context for each item in this experiment provided a trigger for agreement checking with temporal information encoded on the verb, i.e., morphological aspect marking. The aspect-related Negativity obtained for aspect agreement mismatches reflects a violated expectation concerning verbal inflection (in the example above, the expected verb phrase was Sophie is X-ing rather than Sophie X-s in condition d. The absence of an additional P600 for aspect processing suggests that the mismatch did not

  9. Effects of medium-pressure UV lamps radiation on water quality in a chlorinated indoor swimming pool.

    Science.gov (United States)

    Cassan, Delphine; Mercier, Béatrice; Castex, Françoise; Rambaud, André

    2006-03-01

    The aim of our study was to determine the impact of medium-pressure UV lamps radiation on water quality in a chlorinated indoor swimming pool. An indoor swimming pool was equipped with two medium-pressure UV lamps. We collected eight samples of water daily over a four-weeks period and measured total and free chlorine, pH, water temperature, bacteriological parameters, total organic carbon and trihalomethanes. During the first week, which served as control, medium-pressure UV lamps were turned off. During the next three weeks, medium-pressure UV lamps were kept on 24 h per day. The third week, we reduced the level of the injected chlorine into water, and the last week we also reduced the water renewal volume by 27%. Our results showed that bacteriological parameters remained within allowable french limits. When medium-pressure UV lamps were kept on, total, free and active chlorine levels were significantly increased (P<0.001), whereas combined chlorine level were significantly decreased (P<0.001 and P<0.05, respectively). The levels of chloroform and bromodichloromethane were significantly increased when medium-pressure UV lamps were kept on (P<0.001), whereas chlorodibromomethane and bromoform levels significantly decreased (P<0.05 and P<0.001, respectively). The additional formation of chloroform and bromodichloromethane may be explained by the increase in active chlorine and by radicalizing mechanisms initiated by UV radiation.

  10. Criticality safety calculations of the Soreq research reactor storage pool

    Energy Technology Data Exchange (ETDEWEB)

    Caner, M.; Hirshfeld, H.; Nagler, A.; Silverman, I.; Bettan, M. [Soreq Nuclear Research Center, Yavne 81800 (Israel); Levine, S.H. [Penn State University, University Park 16802 (United States)

    2001-07-01

    The IRR-l spent fuel is to be relocated in a storage pool. The present paper describes the actual facility and summarizes the Monte Carlo criticality safety calculations. The fuel elements are to be placed inside cadmium boxes to reduce their reactivity. The fuel element is 7.6 cm by 8.0 cm in the horizontal plane. The cadmium box is effectively 9.7 cm by 9.7 cm, providing significant water between the cadmium and the fuel element. The present calculations show that the spent fuel storage pool is criticality safe even for fresh fuel elements. (author)

  11. Speech by Prime Minister Francois Fillon. Visit of the Jules Horowitz experimental reactor works on the Commissariat a l'Energie et aux Energies Alternatives site. Cadarache, May 3, 2010; Discours du Premier ministre Francois FILLON Cadarache, lundi 3 mai 2010. Visite du chantier du Reacteur experimental Jules Horowitz sur le site du Commissariat a l'Energie Atomique et aux Energies Alternatives

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2010-07-01

    In this speech, the French Prime Minister evokes the present context, the importance of strategic technologies, and the challenge of investing in these technologies within a context of reduction of public expenses. He comments the decision of his government to finance research and education activities in different domains, and more specifically in the energy sector with this fourth generation Jules Horowitz experimental reactor. He recalls that the nuclear sector has always been very important to the eyes of the successive French governments, and outlines how this reactor will contribute to reactor operational optimization, lifetime extension and safety, nuclear fuel development, etc.

  12. Solar thermal activation study of the Land of Hessen. Study on solar options for municipal swimming pools, gymnasia and sports centers in Hessen. Solarthermische Aktivierungsstudie Hessen. Studie zur solaren Eignung von kommunalen Freibaedern sowie Turn- und Sporthallen in Hessen

    Energy Technology Data Exchange (ETDEWEB)

    1994-09-01

    This study is to give communities and districts in the Land of Hessen a decision aid on whether solar service water or pool water heating would be an economically efficient alternative in numerical swimming pools or sports centers. (orig.)

  13. Microbiological quality of swimming-pool waters in the province of Badajoz (Spain); Calidad microbiologica de las aguas de piscina en la provinca de Badajoz

    Energy Technology Data Exchange (ETDEWEB)

    Villalba Doblas, A. M.; Ambel Carracedo, M. P.; Cobos Rodriguez, J. G.

    2006-07-01

    The object of the actual work is to evaluate the microbiological quality of swimming pool waters in the province of Badajoz, 79 samples in 33 cities, according to criteria required by the Decreto 54/2002 of the Comunidad Autonoma of Extremadura. the work describes the possible origins of the pollution in the swimming-pool waters and the risks. The parameters analyzed were Termotolerant Coliforms, Faecal streptococci, S. aureus, P. aerogenes, Sulphate reducing bacteria and Salmonella spp. Results show that 62% of these fulfil microbiological quality criteria. the presence of Sulphate reducing bacteria was found in 24% of the samples, and P. aerogenes was detected in 16% of them. (Author) 20 refs.

  14. Evaluation of the Pseudalert/Quanti-Tray MPN Test for the Rapid Enumeration of Pseudomonas aeruginosa in Swimming Pool and Spa Pool Waters.

    Science.gov (United States)

    Sartory, David P; Brewer, Megan; Beswick, Agnieszka; Steggles, Darron

    2015-12-01

    This study assessed the performance of a new most probable number test (Pseudalert/Quanti-Tray) for the enumeration of Pseudomonas aeruginosa from swimming pool and spa pool waters by comparing it to the international and national membrane filtration-based culture methods for P. aeruginosa: ISO 16266:2006 and UK The Microbiology of Drinking Water-Part 8 (MoDW Part 8) which both use Pseudomonas CN agar. The comparison was based on the calculation of mean relative differences between the two methods conducted according to ISO 17994:2014. Using both routine pool water samples (149 from 8 laboratories) and artificially contaminated samples (309 from 7 laboratories), paired counts from each sample and enumeration method were analysed. For routine samples, there were insufficient data for a conclusive assessment, but the data do indicate at least equivalent performance of Pseudalert/Quanti-Tray to the reference methods. For the artificially contaminated samples, the data also did not result in a statistically conclusive assessment but did indicate potentially better performance of Pseudalert/Quanti-Tray. Combining the data from the routine samples and artificially contaminated samples resulted in an ISO 17994 outcome that the two methods were not statistically significantly different. Thus, the Pseudalert/Quanti-Tray method is an acceptable alternative to ISO 16266 and MoDW Part 8. The Pseudalert/Quanti-Tray method has the advantage in that it does not require confirmation testing, and of providing confirmed counts within 24-28 h incubation compared to 40-48 h or longer for the ISO 16266 and MoDW Part 8 methods.

  15. Radiological performance of hot water layer system in open pool type reactor

    Directory of Open Access Journals (Sweden)

    Amr Abdelhady

    2013-06-01

    Full Text Available The paper presents the calculated dose rate carried out by using MicroShield code to show the importance of hot water layer system (HWL in 22 MW open pool type reactor from the radiation protection safety point of view. The paper presents the dose rate profiles over the pool surface in normal and abnormal operations of HWL system. The results show that, in case of losing the hot water layer effect, the radiation dose rate profiles over the pool surface will increase from values lower than the worker permissible dose limits to values very higher than the permissible dose limits.

  16. Evolution of the implementation level of self-monitoring programmes for outdoor swimming pools in Araba/Álava

    Directory of Open Access Journals (Sweden)

    Raquel Hernández García

    2012-12-01

    Full Text Available The main aim of this study was to carry out an assessment of the implementation level of the self-monitoring programme for outdoor swimming pools in Araba/Álava over a six-year period (2006-2011. For this purpose, inspections were carried out using checklists based on technical guidelines designed to unify criteria and assess the different plans within each self-monitoring programme, including the following: 1. Water Treatment and Monitoring; 2. Water analysis; 3. Cleansing and Disinfection; 4. Safety, Best Practices and User information; 5. Inspection and Maintenance; 6. Pest control; 7. Suppliers, Products and Services. Consensus-based assessments of each plan were also used to objectively evaluate the facilities and the level of implementation of the self-monitoring programme.

  17. The risk of contracting infectious diseases in public swimming pools: a review

    Directory of Open Access Journals (Sweden)

    Zsófia Barna

    2012-12-01

    Full Text Available A review of pathogenic microorganisms presenting risk of infection in pool based artificial recreational water venues is extracted from the available scientific literature. The microorganisms are grouped both according to their way of spread and their survival and growth strategies and their characteristics relevant for the pool and spa based recreation are discussed. In order to put the proposed risks on a solid basis, among others a ten year excerpt of the waterborne disease statistics of the Centers for Disease Control and Prevention (CDC is used throughout the article.

  18. Cost estimates of operating onsite spent fuel pools after final reactor shutdown

    Energy Technology Data Exchange (ETDEWEB)

    Rod, S R

    1991-08-01

    This report presents estimates of the annual costs of operating spent fuel pools at nuclear power stations after the final shutdown of one or more onsite reactors. Its purpose is to provide basic spent fuel storage cost information for use in evaluating DOE's reference nuclear waste management system, as well as alternate systems. The basic model of an independent spent fuel storage installation (ISFSI) used in this study was based on General Electric Corporation's Morris Operation and was modified to reflect mean storage capabilities at an unspecified, or generic,'' US reactor site. Cost data for the model came from several sources, including both operating and shutdown nuclear power stations and existing ISFSIs. Duke Power Company has estimated ISFSI costs based on existing spent fuel storage costs at its nuclear power stations. Similarly, nuclear material handling facilities such as the Morris Operation, the West Valley Demonstration Project, and the retired Humbolt Bay nuclear power station have compiled spent fuel storage cost data based on years of operating experience. Consideration was given to the following factors that would cause operating costs to vary among pools: (1) The number of spent fuel pools at a given reactor site; (2) the number of operating and shutdown reactors onsite; (3) geographic location; and (4) pool storage capacity. 10 ref., 6 figs., 7 tabs.

  19. 3-dimensional thermohydraulic analysis of KALIMER reactor pool during unprotected accidents

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Yong Bum; Hahn Do Hee

    2003-01-01

    During a normal reactor scram, the heat generation is reduced almost instantaneously while the coolant flow rate follows the pump coastdown. This mismatch between power and flow results in a situation where the core flow entering the hot pool is at a lower temperature than the temperature of the bulk pool sodium. This temperature difference leads to thermal stratification. Thermal stratification can occur in the hot pool region if the entering coolant is colder than the existing hot pool coolant and the flow momentum is not large enough to overcome the negative buoyancy force. Since the fluid of hot pool enters IHXs, the temperature distribution of hot pool can alter the overall system response. Hence, it is necessary to predict the pool coolant temperature distribution with sufficient accuracy to determine the inlet temperature conditions for the IHXs and its contribution to the net buoyancy head. Therefore, two-dimensional hot pool thermohydraulic model named HP2D has been developed. In this report code-to-code comparison analysis between HP2D and COMMIX-1AR/P has been performed in the case of steady-state and UTOP.

  20. Dynamic real-time monitoring of chloroform in an indoor swimming pool air using open-path Fourier transform infrared spectroscopy.

    Science.gov (United States)

    Chen, M-J; Duh, J-M; Shie, R-H; Weng, J-H; Hsu, H-T

    2016-06-01

    This study used open-path Fourier transform infrared (OP-FTIR) spectroscopy to continuously assess the variation in chloroform concentrations in the air of an indoor swimming pool. Variables affecting the concentrations of chloroform in air were also monitored. The results showed that chloroform concentrations in air varied significantly during the time of operation of the swimming pool and that there were two peaks in chloroform concentration during the time of operation of the pool. The highest concentration was at 17:30, which is coincident with the time with the highest number of swimmers in the pool in a day. The swimmer load was one of the most important factors influencing the chloroform concentration in the air. When the number of swimmers surpassed 40, the concentrations of chloroform were on average 4.4 times higher than the concentration measured without swimmers in the pool. According to the results of this study, we suggest that those who swim regularly should avoid times with highest number of swimmers, in order to decrease the risk of exposure to high concentrations of chloroform. It is also recommended that an automatic mechanical ventilation system is installed to increase the ventilation rate during times of high swimmer load.

  1. An insight of disinfection by-product (DBP) formation by alternative disinfectants for swimming pool disinfection under tropical conditions.

    Science.gov (United States)

    Yang, Linyan; Schmalz, Christina; Zhou, Jin; Zwiener, Christian; Chang, Victor W-C; Ge, Liya; Wan, Man Pun

    2016-09-15

    Sodium hypochlorite (NaClO) is the most commonly used disinfectant in pool treatment system. Outdoor pools usually suffer from the strong sunlight irradiation which degrades the free chlorine rapidly. In addition, more pools start to adopt the recirculation of swimming pool water, which intensifies the disinfection by-product (DBP) accumulation issue. Given these potential drawbacks of using NaClO in the tropical environment, two alternative organic-based disinfectants, trichloroisocyanuric acid (TCCA, C3Cl3N3O3) and bromochlorodimethylhydantoin (BCDMH, C5H6BrClN2O2), were investigated and compared to NaClO in terms of their self-degradation and the formation of DBPs, including trihalomethanes (THMs) and haloacetic acids (HAAs), under simulated tropical climate conditions. The result reveals that halogen stabilizer, TCCA, had the advantages of slower free chlorine degradation and lower DBP concentration compared to NaClO, which makes it a good alternative disinfectant. BCDMH was not recommended mainly due to the highly reactive disinfecting ingredient, hypobromous acid (HBrO), which fails to sustain the continuous disinfection requirement. Total disinfectant dosage was the main factor that affects residual chlorine/bromine and THM/HAA formation regardless of different disinfectant dosing methods, e.g. shock dosing (one-time spiking) in the beginning, and continuous dosing during the whole experimental period. Two-stage second-order-kinetic-based models demonstrate a good correlation between the measured and predicted data for chlorine decay (R(2) ≥ 0.95), THM (R(2) ≥ 0.99) and HAA (R(2) ≥ 0.83) formation. Higher temperature was found to enhance the DBP formation due to the temperature dependence of reaction rates. Thus, temperature control of pools, especially for those preferring higher temperatures (e.g. hydrotherapy and spa), should take both bather comfort and DBP formation potential into consideration. It is also observed that chlorine competition

  2. Design guide for Category III reactors: pool type reactors. [US DOE

    Energy Technology Data Exchange (ETDEWEB)

    Brynda, W J; Lobner, P R; Powell, R W; Straker, E A

    1978-11-01

    The Department of Energy (DOE) in the ERDA Manual requires that all DOE-owned reactors be sited, designed, constructed, modified, operated, maintained, and decommissioned in a manner that gives adequate consideration to health and safety factors. Specific guidance pertinent to the safety of DOE-owned reactors is found in Chapter 0540 of the ERDA Manual. The purpose of this Design Guide is to provide additional guidance to aid the DOE facility contractor in meeting the requirement that the siting, design, construction, modification, operation, maintenance, and decommissioning of DOE-owned reactors be in accordance with generally uniform standards, guides, and codes which are comparable to those applied to similar reactors licensed by the Nuclear Regulatory Commission (NRC). This Design Guide deals principally with the design and functional requirement of Category III reactor structures, components, and systems.

  3. Overview of pool hydraulic design of Indian prototype fast breeder reactor

    Indian Academy of Sciences (India)

    K Velusamy; P Chellapandi; S C Chetal; Baldev Raj

    2010-04-01

    Thermal hydraulics plays an important role in the design of liquid metal cooled fast breeder reactor components, where thermal loads are dominant. Detailed thermal hydraulic investigations of reactor components considering multi-physics heat transfer are essential for choosing optimum designs among the various possibilities. Pool hydraulics is multi-dimensional in nature and simple one-dimensional treatment for the same is often inadequate. Computational Fluid Dynamics (CFD) plays a critical role in the design of pool type reactors and becomes an increasingly popular tool, thanks to the advancements in computing technology. In this paper, thermal hydraulic characteristics of a fast breeder reactor, design limits and challenging thermal hydraulic investigations carried out towards successful design of Indian Prototype Fast Breeder Reactor (PFBR) that is under construction, are highlighted. Special attention is paid to phenomena like thermal stratification, thermal stripping, gas entrainment, inter-wrapper flow in decay heat removal and multiphysics cellular convection. The issues in these phenomena and the design solutions to address them satisfactorily are elaborated. Experiments performed for special phenomena, which are not amenable for CFD treatment and experiments carried out for validation of the computer codes have also been described.

  4. System for reducing heat losses from indoor swimming pools by use of automatic covers. Final report, October 1, 1993--September 30, 1995

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1996-01-01

    This final report is an account of the principal activities of Lof Energy Systems, Inc. in a two-year project funded by the Energy Related Inventions Program (ERIP) of the U.S. Department of Energy. The primary objective has been the development of a fully practical and economical system for saving energy in indoor swimming pools by use of motorized covers. The goal is wide-spread use of a fully developed product, in institutional swimming pools. Four major tasks, depicted in the accompanying Performance Schedule, have been completed, and one other has been initiated and its completion committed. Principal accomplishments have been the selection and improvement of cover materials and designs, lengthening and strengthening of reels and improvements in motorized components and their control, design and installation of pool covers in full scale demonstration and evaluation of fully developed commercial system, preparation and dissemination of manuals and reports, finalization of arrangements for Underwriters Laboratory certification of products, and final report preparation and submission. Of greatest significance has been the successful demonstration of the fully developed system and the verification and reporting by an energy consultant of the large savings resulting from pool cover use. Probably the best evidence of success of the DOE-ERIP project in advancing this invention to a commercial stage is its acceptance for sale by the Lincoln Equipment Company, a national distributor of swimming pool supplies and equipment. A copy of the relevant page in the Lincoln catalog is included in this report as Annex A. Representatives of that company now offer Tof motorized pool cover systems to their pool owner customers. In addition to the plans for securing UL certification the company expects to continue making design improvements that can increase system reliability, durability, and cost-effectiveness.

  5. Fuel Burnup and Fuel Pool Shielding Analysis for Bushehr Nuclear Reactor VVER-1000

    Science.gov (United States)

    Hadad, Kamal; Ayobian, Navid

    Bushehr Nuclear power plant (BNPP) is currently under construction. The VVER-1000 reactor will be loaded with 126 tons of about 4% enriched fuel having 3-years life cycle. The spent fuel (SF) will be transferred into the spent fuel pool (SPF), where it stays for 8 years before being transferred to Russia. The SPF plays a crucial role during 8 years when the SP resides in there. This paper investigates the shielding of this structure as it is designed to shield the SF radiation. In this study, the SF isotope inventory, for different cycles and with different burnups, was calculated using WIMS/4D transport code. Using MCNP4C nuclear code, the intensity of γ rays was obtained in different layers of SFP shields. These layers include the water above fuel assemblies (FA) in pool, concrete wall of the pool and water laid above transferring fuels. Results show that γ rays leakage from the shield in the mentioned layers are in agreement with the plant's PSAR data. Finally we analyzed an accident were the water height above the FA in the pool drops to 47 cm. In this case it was observed that exposure dose above pool, 10 and 30 days from the accident, are still high and in the levels of 1000 and 758 R/hr.

  6. 上海市游泳场所安全管理的现状及对策%Safety Management Status of the Swimming Pools in Shanghai

    Institute of Scientific and Technical Information of China (English)

    沈伟

    2014-01-01

    以上海市拥有经营游泳项目行政许可的游泳场所为研究对象,采用问卷调查等方法,调查游泳场所数量、分布、人口与场所比例、类型、活动人数等基本情况;分析游泳场所管理结构和现状;调查游泳场所安全保障状况,结果显示当前各中心城区之间和郊区之间的每万人拥有游泳场所数量相比较存在着较大差距,分布不均衡;大型水上娱乐游泳场所较少;救生员将近缺少3成左右;救生员的休息环境有3成左右感觉较差,救生员有上岗排班制度,但有5成救生员没有执行交接岗制度等问题,并据此提出对策建议。%Taking the Shanghai swimming pools that have the administrative license as the subjects and by the method of questionnaire, the author made a survey of the basic information of the pools, such as the number, location, proportion of the population to pools, category, number of the swimmers, etc. The management structure and status of the swimming pools were analyzed and the security measures of the pools were investigated. The result shows that the locations of the swimming pools are unbalanced. There is a great gap between the number of the swimming pools per ten thousand people in the urban areas and that in the suburbs. The number of the large-scale water amusement park is not enough. Another 30 percent of the lifeguards are needed. And about 30 percent of the lifeguards have a bad feeling toward the lounges for rest. There is a job scheduling system for the lifeguards, but half of the lifeguards do not follow the work-handover system. Suggestions are put forward.

  7. Inspection of state of spent fuel elements stored in RA reactor spent fuel storage pool

    Energy Technology Data Exchange (ETDEWEB)

    Aden, V.G.; Bulkin, S.Yu.; Sokolov, A.V. [Research and Development Institute of Power Engineering, Moscow (Russian Federation); Matausek, M.V.; Vukadin, Z. [VINCA Institute of Nuclear Science, Belgrade (Yugoslavia)

    1999-07-01

    About five thousand spent fuel elements from RA reactor have been stored for over 30 years in sealed aluminum barrels in the spent fuel storage pool. This way of storage does not provide complete information about the state of spent fuel elements or the medium inside the barrels, like pressure or radioactivity. The technology has recently been developed and the equipment has been manufactured to inspect the state of the spent fuel and to reduce eventual internal pressure inside the aluminum barrels. Based on the results of this inspection, a procedure will be proposed for transferring spent fuel to a more reliable storage facility. (author)

  8. Detectability prediction for a thermoacoustic sensor in the breazeale nuclear reactor pool

    Energy Technology Data Exchange (ETDEWEB)

    Smith, James [Idaho National Laboratory, Idaho Falls, ID (United States); Hrisko, Joshua [Idaho National Laboratory, Idaho Falls, ID (United States); Garrett, Steven [Idaho National Laboratory, Idaho Falls, ID (United States)

    2016-03-01

    Laboratory experiments have suggested that thermoacoustic engines can be in- corporated within nuclear fuel rods. Such engines would radiate sounds that could be used to measure and acoustically-telemeter information about the op- eration of the nuclear reactor (e.g., coolant temperature or uxes of neutrons or other energetic particles) or the physical condition of the nuclear fuel itself (e.g., changes in temperature, evolved gases) that are encoded as the frequency and/or amplitude of the radiated sound [IEEE Measurement and Instrumen- tation 16(3), 18-25 (2013)]. For such acoustic information to be detectable, it is important to characterize the vibroacoustical environments within reactors. Measurements will be presented of the background noise spectra (with and with- out coolant pumps) and reverberation times within the 70,000 gallon pool that cools and shields the fuel in the 1 MW research reactor on Penn State's campus using two hydrophones, a piezoelectric projector, and an accelerometer. Sev- eral signal-processing techniques will be demonstrated to enhance the measured results. Background vibrational measurement were also taken at the 250 MW Advanced Test Reactor, located at the Idaho National Laboratory, using ac- celerometers mounted outside the reactor's pressure vessel and on plumbing will also be presented. The detectability predictions made in the thesis were validated in September 2015 using a nuclear ssion-heated thermoacoustic sensor that was placed in the core of the Breazeale Nuclear Reactor on Penn State's campus. Some features of the thermoacoustic device used in that experiment will also be revealed. [Work supported by the U.S. Department of Energy.

  9. Review of fuel assembly and pool thermal hydraulics for fast reactors

    Energy Technology Data Exchange (ETDEWEB)

    Roelofs, Ferry, E-mail: roelofs@nrg.eu; Gopala, Vinay R.; Jayaraju, Santhosh; Shams, Afaque; Komen, Ed

    2013-12-15

    Highlights: • Literature review of fuel assembly and pool thermal hydraulics for fast reactors. • Experiments and state-of-the-art simulations. • For wire wrapped fuel assemblies RANS for complete fuel assembly is state-of-the-art, LES serves reference. • For pool thermal hydraulics, typically 5 to 20 million computational volumes are used in RANS simulations. • Gas entrainment analyses are extremely demanding as in addition they request multiphase modelling. -- Abstract: Liquid metal cooled reactors are envisaged to play an important role in the future of nuclear energy production because of their possible efficient use of uranium and the possibility to reduce the volume and lifetime of nuclear waste. Thermal-hydraulics is recognized as a key scientific subject in the development of such reactors. Two important challenges for the design of liquid metal fast reactors (LMFRs) are fuel assembly and pool thermal hydraulics. The heart of every nuclear reactor is the core, where the nuclear chain reaction takes place. Heat is produced in the nuclear fuel and transported to the coolant. LMFR core designs consist of many fuel assemblies which in turn consist of a large number of fuel rods. Wire wraps are commonly envisaged as spacer design in LMFR fuel assemblies. For the design and safety analyses of such reactors, simulations of the heat transport within the core are essential. The flow exiting the core is made up of the outlets of many different fuel assemblies. The liquid metal in these assemblies may be heated up to different temperatures. This leads to temperature fluctuations on various above core structures. As these temperature fluctuations may lead to thermal fatigue damage of the structures, an accurate characterization of the liquid metal flow field in the above core region is very important. This paper will provide an overview of state-of-the-art evaluations of fuel assembly and pool thermal hydraulics for LMFRs. It will show the tight interaction

  10. SPARC fast reactor design : Design of two passively safe metal-fuelled sodium-cooled pool-type small modular fast reactors with Autonomous Reactivity Control

    OpenAIRE

    Lindström, Tobias

    2015-01-01

    In this master thesis a small modular sodium-cooled metal-fuelled pool-type fast reactor design, called SPARC - Safe and Passive with Autonomous Reactivity control, has been designed. The long term reactivity changes in the SPARC are managed by implementation of the the Autonomous Reactivity Control (ARC) system, which is the novelty of the design. The overall design is mainly based on the Integral Fast Reactor project (IFR), which experimentally demonstrated the passive safety characteristic...

  11. E-SCAPE: A scale facility for liquid-metal, pool-type reactor thermal hydraulic investigations

    Energy Technology Data Exchange (ETDEWEB)

    Van Tichelen, Katrien, E-mail: kvtichel@sckcen.be [SCK-CEN, Boeretang 200, 2400 Mol (Belgium); Mirelli, Fabio, E-mail: fmirelli@sckcen.be [SCK-CEN, Boeretang 200, 2400 Mol (Belgium); Greco, Matteo, E-mail: mgreco@sckcen.be [SCK-CEN, Boeretang 200, 2400 Mol (Belgium); Viviani, Giorgia, E-mail: giorgiaviviani@gmail.com [University of Pisa, Lungarno Pacinotti 43, 56126 Pisa (Italy)

    2015-08-15

    Highlights: • The E-SCAPE facility is a thermal hydraulic scale model of the MYRRHA fast reactor. • The focus is on mixing and stratification in liquid-metal pool-type reactors. • Forced convection, natural convection and the transition are investigated. • Extensive instrumentation allows validation of computational models. • System thermal hydraulic and CFD models have been used for facility design. - Abstract: MYRRHA (Multi-purpose hYbrid Research Reactor for High-tech Applications) is a flexible fast-spectrum research reactor under design at SCK·CEN. MYRRHA is a pool-type reactor with lead bismuth eutectic (LBE) as primary coolant. The proper understanding of the thermal hydraulic phenomena occurring in the reactor pool is an important issue in the design and licensing of the MYRRHA system and liquid-metal cooled reactors by extension. Model experiments are necessary for understanding the physics, for validating experimental tools and to qualify the design for the licensing. The E-SCAPE (European SCAled Pool Experiment) facility at SCK·CEN is a thermal hydraulic 1/6-scale model of the MYRRHA reactor, with an electrical core simulator, cooled by LBE. It provides experimental feedback to the designers on the forced and natural circulation flow patterns. Moreover, it enables to validate the computational methods for their use with LBE. The paper will elaborate on the design of the E-SCAPE facility and its main parameters. Also the experimental matrix and the pre-test analysis using computational fluid dynamics (CFD) and system thermal hydraulics codes will be described.

  12. Identification of Mycobacterium marinum 65 kD heat shock protein gene by polymerase chain reaction restriction analysis from lesions of swimming pool granuloma

    Institute of Scientific and Technical Information of China (English)

    2006-01-01

    Background Nontuberculous mycobacterium (NTM) had been reported to cause cutaneous infections which are difficult to interpret due to the variability of the clinical manifestations. Among NTM infections, Mycobacterium marinum (M. marinum) are mostly seen to cause skin infection. It is therefore important to establish a rapid approach for detection and identification of M. marinum from lesions of patients with suspected M. marinum infections. Methods Specimens were obtained from 5 patients with swimming pool granuloma. DNA was extracted and polymerase chain reaction (PCR) was performed. PCR products were digested with Hae III and BstE II, then analysed by pattern restriction analysis to detect heat shock protein (hsp) 65 kD gene. Results The 65 kD hsp gene was found in all specimens from patients with swimming pool granuloma. PCR restriction analysis (PRA) identified all 5 samples to be M. marinum infections, and the result was consistent with that of routine bacteriological identification. The lesions subsided or markedly improved upon treatment. Conclusions PRA is a sensitive, specific and rapid method in identification of mycobacteria. Application of this method will be helpful for early diagnosis of mycobacterial skin infections.

  13. The reactor Cabri; La pile cabri

    Energy Technology Data Exchange (ETDEWEB)

    Ailloud, J.; Millot, J.P. [Commissariat a l' Energie Atomique, Cadarache (France). Centre d' Etudes Nucleaires

    1964-07-01

    It has become necessary to construct in France a reactor which would permit the investigation of the conditions of functioning of future installations, the choice, the testing and the development of safety devices to be adopted. A water reactor of a type corresponding to the latest CEA constructions in the field of laboratory or university reactors was decided upon: it appeared important to be able to evaluate the risks entailed and to study the possibilities of increasing the power, always demanded by the users; on the other hand, it is particularly interesting to clarify the phenomena of power oscillation and the risks of burn out. The work programme for CABRI will be associated with the work carried out on the American Sperts of the same type, during its construction, very useful contacts were made with the American specialists who designed the se reactors. A brief description of the reactor is given in the communication as well as the work programme for the first years with respect to the objectives up to now envisaged. Rough description of the reactor. CABRI is an open core swimming-pool reactor without any lateral protection, housed in a reinforced building with controlled leakage, in the Centre d'Etudes Nucleaires de Cadarache. It lies alone in the middle of an area whose radius is 300 meters long. Control and measurements equipment stand out on the edge of that zone. It consumes MTR fuel elements. The control-safety rods are propelled by compressed air. The maximum flow rate of cooling circuit is 1500 m{sup 3}/h. Transient measurements are recorded in a RW330 unit. Aims and work programme. CABRI is meant for: - studies on the safety of water reactors - for the definition of the safety margins under working conditions: research of maximum power at which a swimming-pool reactor may operate with respect to a cooling accident, of local boiling effect on the nuclear behaviour of the reactor, performances of the control and safety instruments under

  14. The application of computational fluid dynamics and small-scale physical models to assess the effects of operational practices on the risk to public health within large indoor swimming pools.

    Science.gov (United States)

    Lewis, Lowell; Chew, John; Woodley, Iain; Colbourne, Jeni; Pond, Katherine

    2015-12-01

    Swimming pools provide an excellent facility for exercise and leisure but are also prone to contamination from microbial pathogens. The study modelled a 50-m × 20-m swimming pool using both a small-scale physical model and computational fluid dynamics to investigate how water and pathogens move around a pool in order to identify potential risk spots. Our study revealed a number of lessons for pool operators, designers and policy-makers: disinfection reaches the majority of a full-scale pool in approximately 16 minutes operating at the maximum permissible inlet velocity of 0.5 m/s. This suggests that where a pool is designed to have 15 paired inlets it is capable of distributing disinfectant throughout the water body within an acceptable time frame. However, the study also showed that the exchange rate of water is not uniform across the pool tank and that there is potential for areas of the pool tank to retain contaminated water for significant periods of time. 'Dead spots' exist at either end of the pool where pathogens could remain. This is particularly significant if there is a faecal release into the pool by bathers infected with Cryptosporidium parvum, increasing the potential for waterborne disease transmission.

  15. The radionuclides of primary coolant in HANARO and the recent activities performed to reduce the radioactivity or reactor pool water

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Minjin [HANARO Research Reactor Centre, Korea Atomic Energy Research Inst., Taejon (Korea, Republic of)

    1998-10-01

    In HANARO reactor, there have been activities to identify the principal radionuclides and to quantify them under the normal operation. The purposes of such activities were to establish the measure by which we can reduce the radioactivity of the reactor pool water and detect, in early stage, the abnormal symptoms due to the leakage of radioactive materials from the irradiation sample or the damage of the nuclear fuel, etc. The typical radionuclides produced by the activation of reactor coolant are N{sup 16} and Ar{sup 41}. The radionuclides produced by the activation of the core structural material consist of Na{sup 24}, Mn{sup 56}, and W{sup 187}. Of the various radionuclides, governing the radiation level at the pool surface are Na{sup 24}, Ar{sup 41}, Mn{sup 58}, and W{sup 187}. By establishing the hot water layer system on the pool surface, we expected that the radionuclides such as Ar{sup 41} and Mn{sup 56} whose half-life are relatively short could be removed to a certain extent. Since the content of radioactivity of Na{sup 24} occupies about 60% of the total radioactivity, we assumed that the total radiation level would be greatly reduced if we could decrease the radiation level of Na{sup 24}. However the actual radiation level has not been reduced as much as we expected. Therefore, some experiments have been carried out to find the actual causes afterwards. What we learned through the experiments are that any disturbance in reactor pool water layer causes increase of the pool surface radiation level and even if we maintain the hot water layer well, reactor shutdown will be very much likely to happen once the hot water layer is disturbed. (author)

  16. Actinide neutron induced cross section measurements using the oscillation technique in the Minerve reactor

    Energy Technology Data Exchange (ETDEWEB)

    Bernard, B.; Leconte, P.; Gruel, A.; Antony, M.; Di-Salvo, J.; Hudelot, J.P.; Pepino, A.; Lecluze, A. [CEA Cadarache, DEN/CAD/DER/SPRC/LEPh, 13 - Saint-Paul-lez-Durance (France)

    2009-07-01

    CEA is deeply involved research programs concerning nuclear fuel advanced studies (actinides, plutonium), waste management, the scientific and technical support of French PWR reactors and EPR reactor, and innovative systems. In this framework, specific neutron integral experiments have been carried out in the critical ZPR (zero power reactor) facilities of the CEA at Cadarache such as MINERVE, EOLE and MASURCA. This paper deals with MINERVE Pool Reactor experiments. MINERVE is mainly devoted to neutronics studies of different reactor core types. The aim is to improve the knowledge of the integral absorption cross sections of actinides (OSMOSE program), of new absorbers (OCEAN program) and also for fission Products (CBU program) in thermal, epithermal and fast neutron spectra. (authors)

  17. Post shut-down decay heat removal from nuclear reactor core by natural convection loops in sodium pool

    Energy Technology Data Exchange (ETDEWEB)

    Rajamani, A. [Department of Mechanical Engineering, Indian Institute of Technology Madras, Chennai 600036 (India); Sundararajan, T., E-mail: tsundar@iitm.ac.in [Department of Mechanical Engineering, Indian Institute of Technology Madras, Chennai 600036 (India); Prasad, B.V.S.S.S. [Department of Mechanical Engineering, Indian Institute of Technology Madras, Chennai 600036 (India); Parthasarathy, U.; Velusamy, K. [Nuclear Engineering Group, Indira Gandhi Centre for Atomic Research, Kalpakkam 603102 (India)

    2016-05-15

    Highlights: • Transient simulations are performed for a worst case scenario of station black-out. • Inter-wrapper flow between various sub-assemblies reduces peak core temperature. • Various natural convection paths limits fuel clad temperatures below critical level. - Abstract: The 500 MWe Indian pool type Prototype Fast Breeder Reactor (PFBR) has a passive core cooling system, known as the Safety Grade Decay Heat Removal System (SGDHRS) which aids to remove decay heat after shut down phase. Immediately after reactor shut down the fission products in the core continue to generate heat due to beta decay which exponentially decreases with time. In the event of a complete station blackout, the coolant pump system may not be available and the safety grade decay heat removal system transports the decay heat from the core and dissipates it safely to the atmosphere. Apart from SGDHRS, various natural convection loops in the sodium pool carry the heat away from the core and deposit it temporarily in the sodium pool. The buoyancy driven flow through the small inter-wrapper gaps (known as inter-wrapper flow) between fuel subassemblies plays an important role in carrying the decay heat from the sub-assemblies to the hot sodium pool, immediately after reactor shut down. This paper presents the transient prediction of flow and temperature evolution in the reactor subassemblies and the sodium pool, coupled with the safety grade decay heat removal system. It is shown that with a properly sized decay heat exchanger based on liquid sodium and air chimney stacks, the post shutdown decay heat can be safely dissipated to atmospheric air passively.

  18. Characterization of radioactive contaminants and water treatment trials for the Taiwan Research Reactor's spent fuel pool.

    Science.gov (United States)

    Huang, Chun-Ping; Lin, Tzung-Yi; Chiao, Ling-Huan; Chen, Hong-Bin

    2012-09-30

    There were approximately 926 m(3) of water contaminated by fission products and actinides in the Taiwan Research Reactor's spent fuel pool (TRR SFP). The solid and ionic contaminants were thoroughly characterized using radiochemical analyses, scanning electron microscopy equipped with an energy dispersive spectrometer (SEM-EDS), and inductively coupled plasma optical emission spectrometry (ICP-OES) in this study. The sludge was made up of agglomerates contaminated by spent fuel particles. Suspended solids from spent ion-exchange resins interfered with the clarity of the water. In addition, the ionic radionuclides such as (137)Cs, (90)Sr, U, and α-emitters, present in the water were measured. Various filters and cation-exchange resins were employed for water treatment trials, and the results indicated that the solid and ionic contaminants could be effectively removed through the use of filters and cation exchange resins, respectively. Interestingly, the removal of U was obviously efficient by cation exchange resin, and the ceramic depth filter composed of diatomite exhibited the properties of both filtration and adsorption. It was found that the ceramic depth filter could adsorb β-emitters, α-emitters, and uranium ions. The diatomite-based ceramic depth filter was able to simultaneously eliminate particles and adsorb ionic radionuclides from water.

  19. Spectacular energy technology: Panorama-Sauna Holzweiler. KfW funds indoor swimming pools as 'process heat'; Energetisch spektakulaer: Panorama-Sauna Holzweiler. KfW foerdert Schwimmbaeder als 'Prozesswaerme'

    Energy Technology Data Exchange (ETDEWEB)

    Meissner, Rolf

    2008-11-15

    The ''Panorama-Sauna'' at Grafschaft is a big indoor swimming pool and Sauna centre in a rural region not far from Cologne and Koblenz. The charm of this spectacular solar project is in its minimalism. Conventional solar thermal power systems, in contrast, tend to be complex and prone to failure. (orig.)

  20. Effect of ozonation of swimming pool water on formation of volatile disinfection by-products - A laboratory study

    DEFF Research Database (Denmark)

    Hansen, Kamilla Marie Speht; Spiliotopoulou, Aikaterini; Cheema, Waqas Akram;

    2016-01-01

    byproducts during subsequent chlorination. The ozone reaction was observed to behave according to first order kinetics. For tap water half-life was 4 min whilst polluted and unpolluted pool water exhibited half-life of 8 and 11 min, respectively. When ozonation dosage was repeated half-life of ozone...

  1. Trihalometanos en el agua de piscinas en cuatro zonas de España participantes en el proyecto INMA Trihalomethanes in swimming pool water in four areas of Spain participating in the INMA project

    Directory of Open Access Journals (Sweden)

    Laia Font-Ribera

    2010-12-01

    Full Text Available Objetivo: La natación es uno de los deportes más practicados en España, por personas de todas las edades y condiciones físicas. También es una vía de exposición a subproductos de la desinfección, compuestos potencialmente tóxicos. Su concentración en el agua de las piscinas no está legislada y es poco conocida. El objetivo de este trabajo es describir la concentración de trihalometanos en el agua de piscinas de los municipios de cuatro cohortes del estudio INMA. Métodos: En julio de 2009 se analizaron los trihalometanos en el agua de piscinas (n=27 de Asturias, Granada, Valencia y Sabadell. Resultados: La concentración media de trihalometanos totales fue de 42,7µg/l (desviación estándar [DE]=19,1 en las piscinas interiores y de 151,2µg/l (DE=80,7 en las exteriores, predominando siempre el cloroformo. Granada tuvo los valores más bajos. Conclusión: La concentración de trihalometanos en el agua de piscinas presenta una gran variabilidad. Las piscinas exteriores tienen valores más altos, superando mayoritariamente los límites legales establecidos para el agua de consumo.Objective: Swimming is one of the most widely practiced sports in Spain among people of all ages and physical conditions. This activity is also a source of exposure to disinfection by-products (DBP, which are potentially toxic. The DBP concentration in swimming pool water is not regulated and is poorly known. The aim of this study was to describe trihalomethane concentrations in swimming pool water in the municipalities of four cohorts of the INMA project. Methods: In July 2009, trihalomethanes were analyzed in water from 27 swimming pools in Asturias, Granada, Valencia and Sabadell. Results: The mean total trihalomethane concentration was 42.7µg/L (standard deviation [SD]=19.1 in indoor pools and 151.2µg/L (SD=80.7 in outdoor pools. In all pools, the most abundant trihalomethane was always chloroform. The lowest levels were found in Granada. Conclusion

  2. Effect of pH on the formation of disinfection byproducts in swimming pool water – Is less THM better?

    OpenAIRE

    Hansen, Kamilla Marie Speht; Willach, Sarah; Antoniou, Maria; Mosbæk, Hans; Albrechtsen, Hans-Jørgen; Andersen, Henrik Rasmus

    2012-01-01

    This study investigated the formation and predicted toxicity of different groups of disinfection byproducts (DBPs) from human exudates in relation to chlorination of pool water at different pH values. Specifically, the formation of the DBP groups trihalomethanes (THMs), haloacetic acids (HAAs), haloacetonitriles (HANs) and trichloramine (NCl3), resulting from the chlorination of body fluid analog, were investigated at 6.0 ≤ pH ≤ 8.0. Either the initial concentration of active chorine or free ...

  3. 2001-2012年张家港市游泳池水水质监测分析%Analysis and monitoring on water quality of swimming pools in Zhangjiagang City from 2011-2012

    Institute of Scientific and Technical Information of China (English)

    曹莉莉; 陈祝军

    2013-01-01

    目的 了解张家港市游泳池水水质的卫生状况,旨在预防疾病传播,规范游泳场所卫生管理.方法 依据国家有关卫生规范、卫生标准和检验方法,对游泳池水进行采样检验.结果 2011-2012年共采集游泳池池水95批次(211份水样),全部合格的有58批次,合格率为61.0%.样品不合格项目主要是尿素和游离性余氯.结论 张家港市游泳池水水质的卫生状况较差,需加强对经营管理者的业务技能培训,加强公共卫生知识的宣传教育,同时加强监督检测工作.%[Objective]To investigate the sanitary condition of water quality of swimming pools in Zhangjiagang City, prevent the disease transmission, and standardize the health management in swimming places. [Methods]The swimming pool water was sampled and detected according to the related national hygiene specification, hygiene standard and detection method. [Results]A total of 95 batches (211 water samples) were collected from swimming pools during 2011-2012, and 58 batches were qualified. The unqualified indexes mainly included urea and free residual chlorine. [ Conclusion] The sanitary condition of swimming pool water in Zhangjiagang City is not satisfactory. It needs to reinforce the skill training among managers, strengthen the education of public health knowledge, and improve the inspection and detection.

  4. Experimental evaluation of a heat pump for the water-supply heating of a public swimming pool

    Science.gov (United States)

    López, R.; Vaca, M.; Terres, H.; Lizardi, A.; Morales, J.; Chávez, S.

    2017-01-01

    In this work the analysis of the thermodynamic behavior of heat pumps (HP) which supply the energy needed in the public pool at the Aquatic Center of Azcapotzalco was performed. There are 18 installed HP’s but only those needed to provide the energy required are alternately activated. The evaluation was conducted during May and June of 2015. We selected one of the HP to implement temperature and pressure gauges at the inlet and outlet of the compressor. The measurements were made every day at three times, 6:30, 13:00 and 18:00 hours. In a period of 24 hours, 1 000 L evaporated, there was no variation registered overnight, since the pool was covered with plastic to avoid loss of the fluid. The heat pump provided 150 kW to maintain the water temperature at the right level of operation, namely 28 °C. The coefficients of performance (COP) of the HP were 6.39 at 6:30, 7.42 at 13:00 and 7:32 at 18:00 hrs., values which are very close to the one provided by the manufacturer.

  5. The noncondensable gas effects on loss-of-coolant accident steam condensation loads in boiling water reactor pressure suppression pool

    Energy Technology Data Exchange (ETDEWEB)

    Kukita, Y.; Namatame, K.; Shiba, M.; Takeshita, I.

    1983-11-01

    The noncondensable gas effects on the loss-ofcoolant-accident-induced steam condensation loads in the boiling water reactor pressure suppression pool have been investigated with regard to experimental data obtained from a large-scale multivent test program. Previous studies have noted that the presence of the noncondensable gas (air), which initially fills the containment drywell space, stabilizes the direct-contact condensation in the pressure suppression pool and hampers onset of the chugging phenomenon, which induces most significant steam condensation load onto the pool boundary. This was found to be true for the tests with relatively small-break diameters, where the maximum steam mass fluxes in the vent pipe were lower than the upper threshold value for the onset of chugging. However, in the tests with the maximum vent steam mass fluxes moderately higher than the chugging upper threshold value, early depletion of the noncondensable gas tended to result in significant stabilization of steam condensation accompanied by an excursion of temperature of pool water surrounding the vent pipe outlets, which led to a delayed onset of chugging. Due to this combined influence of the noncondensable gas and nonuniform pool temperature, and due to dependence of magnitude of chugging load on the vent steam mass flux, the peak magnitude of the steam condensation load appearing in a blowdown can be very sensitive to the initial and break conditions.

  6. 2012年夏季北京市西城区游泳池水卫生状况分析%Analysis on sanitary conditions of swimming pool water in Xicheng District of Beijing in the summer of 2012

    Institute of Scientific and Technical Information of China (English)

    张晓雪; 李若岚; 李博洋; 程亚杰; 张振伟; 王巍

    2013-01-01

    目的 通过了解2012年夏季北京市西城区游泳池水质卫生状况,为进一步提高游泳池水质提供依据.方法 2012年5--9月对辖区内学校附属、酒店附属、经营类3种不同类型的游泳馆进行监测,每家游泳馆每月采集水样2件,每月监测1次,连续5个月,监测项目包括pH值、浑浊度、尿素、细菌总数、大肠菌群和游离性余氯6项指标.结果 2012年夏季西城区游泳池水共监测水样140件,游泳池水质总体合格率较低,为50.00%.余氯指标合格率仅为55.71%,影响总体合格率.pH值、浑浊度、大肠菌群合格率为100%,尿素、细菌总数的合格率分别为85.71%,95.00%.学校附属、酒店附属、经营类3种不同类型场所的游泳池水合格率不同,经过卡方检验,差异有统计学意义(x2=28.289,P<0.01).学校附属游泳池水质状况最好,经营性类型的游泳池水合格率最低.结论 该区游泳场馆应建立正确净化、消毒程序,及时补充新水,加强监督管理和游泳场馆管理人员培训,保障游泳池水质.%[Objective]To understand the water quality of swimming pools in Xicheng District of Beijing in the summer of 2012, provide scientific evidence for improving water quality of swimming pools. [ Methods ] Three different types of swimming places, which included school affiliated, hotel affiliated and business swimming pools, were monitored from May to September 2012. 2 samples were collected from every swimming place every month, and were monthly monitored for 5 months. The test items included pH value, turbidity, urea, total bacterial count, Coliform group count and free residual chlorine. [Results] A total of 140 water samples were tested in the summer of 2012, and the total qualified rate was low (50.00% ). The qualified rate of residual chlorine was only 55.71% , which affected the total qualified rate. The qualified rates of pH value, turbidity and Coliform group count were 100% , while the

  7. Hygienic evaluation on the construction project of an artificial swimming pool in Shenzhen City%深圳市某人工游泳场所建设项目卫生学评价

    Institute of Scientific and Technical Information of China (English)

    严燕; 钟红霞; 谢敏灵; 姜立民

    2013-01-01

    目的 对深圳市某人工游泳场所进行建设项目卫生学评价,为卫生行政部门卫生许可审核提供技术依据.方法 依照卫生学评价通则对游泳场所进行卫生学调查、卫生工程分析,并检测游泳池水水质卫生指标.结果 该新建人工游泳场所建设项目的选址、总平面布局、功能分区、建筑物卫生学、卫生设施及消毒措施、卫生管理措施等基本符合有关卫生标准.5份游泳池水各7个检测项目的检测结果均合格,合格率为100%.结论 通过建设项目卫生学评价,较好地预防和控制了该人工游泳场所可能存在的健康危害因素.应大力推广公共场所建设项目卫生学评价工作.%[Objective]To cany out the hygienic evaluation of the construction project of an artificial swimming pool in Shenzhen City, provide the technical evidences for hygiene supervision. [Methods] According to the general rule of hygienic evaluation, the hygienic investigation and sanitary engineering analysis were conducted in swimming pool, and the health indexes of swimming pool water were tested. [Results]The site selection, overall layout, sectorization, structural hygiene, sanitary facilities and disinfection measures, as well as health management measures of the construction project of new artificial swimming pool met the requirements of the national laws and regulations. Among 5 samples of swimming pool water, all of 7 indexes accorded with national standards, and the qualified rates were 100%. [ Conclusion ] The possible health risk factors in this artificial swimming pool have been effectively prevented and controlled by the hygiene evaluation, so it is recommended that hygienic evaluation of the construction project should be popularized energetically.

  8. Effect of pH on the formation of disinfection byproducts in swimming pool water – Is less THM better?

    DEFF Research Database (Denmark)

    Hansen, Kamilla Marie Speht; Willach, Sarah; Antoniou, Maria

    2012-01-01

    This study investigated the formation and predicted toxicity of different groups of disinfection byproducts (DBPs) from human exudates in relation to chlorination of pool water at different pH values. Specifically, the formation of the DBP groups trihalomethanes (THMs), haloacetic acids (HAAs......), haloacetonitriles (HANs) and trichloramine (NCl3), resulting from the chlorination of body fluid analog, were investigated at 6.0 ≤ pH ≤ 8.0. Either the initial concentration of active chorine or free chlorine was kept constant in the tested pH range. THM formation was reduced by decreasing pH but HAN, and NCl3...... formation was investigated and found to follow the same pH dependency as without bromide present, with the overall DBP formation increasing, except for HAAs. Estimation of genotoxicity and cytotoxicity of the chlorinated human exudates showed that among the quantified DBP groups, HAN formation were...

  9. Effect of pH on the formation of disinfection byproducts in swimming pool water--is less THM better?

    Science.gov (United States)

    Hansen, Kamilla M S; Willach, Sarah; Antoniou, Maria G; Mosbæk, Hans; Albrechtsen, Hans-Jørgen; Andersen, Henrik R

    2012-12-01

    This study investigated the formation and predicted toxicity of different groups of disinfection byproducts (DBPs) from human exudates in relation to chlorination of pool water at different pH values. Specifically, the formation of the DBP groups trihalomethanes (THMs), haloacetic acids (HAAs), haloacetonitriles (HANs) and trichloramine (NCl(3)), resulting from the chlorination of body fluid analog, were investigated at 6.0 ≤ pH ≤ 8.0. Either the initial concentration of active chorine or free chlorine was kept constant in the tested pH range. THM formation was reduced by decreasing pH but HAN, and NCl(3) formation increased at decreasing pH whereas the formation of HAAs remained constant. Under our experimental conditions, the formation of NCl(3) (suspected asthma inducing compound) at pH = 6.0 was an order of magnitude higher than at pH = 7.5. Furthermore, the effect of the presence of bromide on DBP formation was investigated and found to follow the same pH dependency as without bromide present, with the overall DBP formation increasing, except for HAAs. Estimation of genotoxicity and cytotoxicity of the chlorinated human exudates showed that among the quantified DBP groups, HAN formation were responsible for the majority of the toxicity from the measured DBPs in both absence and presence of bromide.

  10. Irradiation Scheme Design of 14C Production on 49-2 Reactor

    Institute of Scientific and Technical Information of China (English)

    SUN; Zheng; LIU; Xing-min; XU; Zhi-long; ZHANG; Ya-dong

    2012-01-01

    <正>14C is a radioisotope of carbon, it is widely used in pharmacy, medical treatment, agriculture, reconnoiter and archaeology. 49-2 research reactor is a swimming pool style reactor which has operated for more than 40 years. The application of 49-2 reactor includes the radio nuclides production. Therefore, the technical scheme on 14C irradiation in 49-2 reactor should be prepared elaborately.

  11. Feynman-alpha technique for measurement of detector dead time using a 30 kW tank-in-pool research reactor

    CERN Document Server

    Akaho, E H K; Intsiful, J D K; Maakuu, B T; Nyarko, B J B

    2002-01-01

    Reactor noise analysis was carried out for Ghana Research Reactor-1 GHARR-1, a tank-in-pool type reactor using the Feynman-alpha technique (variance-to-mean method). Measurements made at different detector positions and under subcritical conditions showed that the technique could not be used to determine the prompt decay constant for the reactor which is Be reflected with photo-neutron background. However, for very low dwell times the technique was used to measure the dead time of the detector which compares favourably with the value obtained using the alpha-conventional method.

  12. Investigation on water sanitary condition of swimming pools in Shijiazhuang in the Summer of 2011%2011年夏季石家庄市游泳池水质卫生状况调查

    Institute of Scientific and Technical Information of China (English)

    陈凤格; 白萍; 郭占景

    2012-01-01

    目的 了解石家庄市游泳池水质卫生状况和游泳场所的卫生管理情况,为防止传播疾病、保障游泳者的身体健康提供依据.方法 根据《石家庄市2011年公共场所卫生重点监督检查方案》及《公共场所卫生管理条例实施细则》,2011年石家庄市疾病预防控制中心与市卫生监督局共同对市区内所辖游泳池进行了监督采样,石家庄市负责对水样进行化验.结果 游离性余氯、尿素、细菌总数、大肠菌群、pH值、浑浊度的合格率依次为52.0%、81.2%、85.7%、94.1%、97.6%、100.0%;室内与室外游泳池合格率分别为41.5%和28.3%;专业型、生活小区型和附属型游泳池合格率分别为48.7%、27.1%和20.2%.结论 应进一步加强对石家庄市游泳池的监督和管理,确保广大游泳爱好者有安全卫生的游泳环境.%Objective To understand the water sanitary condition of swimming pools and health management of swimming pools in Shijiazhuang City, and provide basis for preventing disease transmission and protecting the health of swimmers. Method According to Key Supervision and Inspection Program for Public Places Health in Shijiazhuang City in 2011 and Implementation Rules of Regulations on Health Administration of Public Places, Shijiazhuang Center for Disease Control and Prevention and Health Supervision Bureau took samples from each swimming pool together, and Shijiazhuang CDC was responsible for laboratory testing of the samples. Results The qualified rates of free residual chlorine, urea, total bacteria, coliform bacteria, pH value and turbidity were 52. 0% , 81. 2% , 85. 7% , 94. 1% , 97.6% and 100. 0% , respectively. The qualified rates of indoor and outdoor swimming pools were 41. 5% and 28. 3% , respectively; and the qualified rates of professional, residental and subsidiary swimming pools were 48.1% , 27. 1% and 20. 2% , respectively. Conclusion We should further strengthen the supervision and

  13. An Innovative Passive Residual Heat Removal System of an Open-Pool Type Research Reactor with Pump Flywheel and Gravity Core Cooling Tank

    Directory of Open Access Journals (Sweden)

    Kwon-Yeong Lee

    2015-01-01

    Full Text Available In an open-pool type research reactor, the primary cooling system can be designed to have a downward flow inside the core during normal operation because of the plate type fuel geometry. There is a flow inversion inside the core from the downward flow by the inertia force of the primary coolant to the upward flow by the natural circulation when the pump is turned off. To delay the flow inversion time, an innovative passive system with pump flywheel and GCCT is developed to remove the residual heat. Before the primary cooling pump starts up, the water level of the GCCT is the same as that of the reactor pool. During the primary cooling pump operation, the water in the GCCT is moved into the reactor pool because of the pump suction head. After the pump stops, the potential head generates a downward flow inside the core by moving the water from the reactor pool to the GCCT and removes the residual heat. When the water levels of the two pools are the same again, the core flow has an inversion of the flow direction, and natural circulation is developed through the flap valves.

  14. The Swimming Pool (oil painting)

    Institute of Scientific and Technical Information of China (English)

    1998-01-01

    Chen Xi was born in 1968 in Chongqing City, Sichuan Province. In 1991, she graduated with a Bachelor’s degree from the Oil Painting Department of the Central Academy of Fine Arts. Her paintings are soaked through with her mixed emotions towards urban life. The city, the concentrated mirror of human civilization, drives the human race further and further away from mother nature Molded ever more strictly by the socialization process, human beings live more and more like commodities. The ever-shrink-

  15. Neutron activation analysis at the Livermore pool-type reactor for the environmental research program. [Identification of trace element contaminants

    Energy Technology Data Exchange (ETDEWEB)

    Ragaini, R.C.; Heft, R.E.; Garvis, D.

    1976-07-02

    Instrumental neutron activation analysis is a technique of trace analysis using measurements of radioactivity induced in the sample by exposure to a source of neutrons. The induced activity is measured by the emitted gamma radiation. Each gamma emitter can then be identified by the energy of the photopeaks produced as the nuclide decays and by the half-life of the neutron-induced activity. A complex computer program GAMANAL has been used to accomplish the major tasks of nuclide identification and quantification. The nuclide data output from GAMANAL is processed by a second computer code NADAC, which develops elemental abundance data from disintegration rates observed. The methods are those employed at the Livermore Pool-Type Reactor in support of the environmental research trace element analysis program. Among the procedures described and discussed are sample preparation, irradiation, analysis, and application of the technique.

  16. Concept of a BNCT line with in-pool fission converter at MARIA reactor in Swierk

    Science.gov (United States)

    Pytel, Krzysztof; Andrzejewski, Krzysztof; Golnik, Natalia; Osko, Jakub

    2009-01-01

    BNCT facility in the Institute of Atomic Energy in Otwock-Swierk is under construction at the horizontal channel H2 of the research reactor MARIA. Measurements of the neutron energy spectrum performed at the front of the H2 experimental channel, have shown that flux of epithermal neutrons (above 10 keV) at the BNCT irradiation port was below 109 n cm-2 s-1 i.e. it was too low to be directly used for the BNCT treatment. Therefore, a fission converter will be placed between the reactor core and the periphery of the graphite reflector of MARIA reactor. The uranium converter will be powered by the densely packed EK-10 fuel elements with 10% enrichment. Preliminary calculations have shown that the total neutron flux in the converter will be about 1013 n cm-2 s-1 and flux of epithermal neutrons at the entrance to the filter/moderator of the beam will be about 2·1013 n cm-2 s-1.

  17. Reactors

    CERN Document Server

    International Electrotechnical Commission. Geneva

    1988-01-01

    This standard applies to the following types of reactors: shunt reactors, current-limiting reactors including neutral-earthing reactors, damping reactors, tuning (filter) reactors, earthing transformers (neutral couplers), arc-suppression reactors, smoothing reactors, with the exception of the following reactors: small reactors with a rating generally less than 2 kvar single-phase and 10 kvar three-phase, reactors for special purposes such as high-frequency line traps or reactors mounted on rolling stock.

  18. Water Quality Evaluation of Swimming Pools Based on Back Propagation Neural Network%应用反向传播(BP)神经网络模型综合评价游泳场所水质

    Institute of Scientific and Technical Information of China (English)

    黄丽红; 王小川; 陈仁杰

    2013-01-01

    [Objective] To build a water quality evaluation model based on back propagation (BP) neural network for better water hygiene management of the swimming pools in Shanghai.[Methods] Based on the exports' proposed standards of water quality grading for swimming pools,random samples were selected.A BP neural network was adopted for training and modeling.The established model was then applied to rapid evaluation of water quality grade of swimming pools in Changning District,Shanghai.[Results] With the help of BP neural network,the prediction accuracy of the water quality evaluation model was up to 95.2% for the training data.Among the water samples from swimming pools in Changning District in 2009,no severe water.pollution was found and more than half (54.44%) of the water samples were at general grade.There were more lightly polluted samples from the community clubs than from the sports institutes and the star-rated hotels.The quality of samples taken from sports institutes was higher than those from the star-rated hotels and the community clubs.[Conclusion] The accuracy of the BP neural network model is high for water quality evaluation.Except for the water sampled from the community clubs' swimming pools,the quality of water in swimming pools of Shanghai Changning District is at a general acceptable level.%[目的]应用反向传播(back-propagation,BP)神经网络模型,构建游泳场所水质综合评价模型,为加强游泳场所水质的卫生管理和保障游泳者的身体健康提供相关依据. [方法]运用专家评价的游泳场所水质分级标准并根据随机数产生样本,使用BP神经网络进行训练与建模.将建立好的BP神经网络模型用于上海市长宁区游泳场所快速水质等级判断. [结果]构建的基于BP神经网络的游泳场所水质综合评价模型对训练数据的预测准确率达到95.2%.2009年上海市长宁区游泳场所水样中,无重度污染水样.水质一般的

  19. Results of a large scale neutron spectrometry and dosimetry comparison exercise at the Cadarache moderator assembly

    Energy Technology Data Exchange (ETDEWEB)

    Thomas, D.J.; Naismith, O.F.; Taylor, G.C. [National Physical Lab., Teddington (United Kingdom); Chartier, J.-L.; Posny, F. [CEA Centre d`Etudes de Fontenay-aux-Roses, 92 (France). Inst. de Protection et de Surete Nucleaire; Klein, H. [Physikalisch-Technische Bundesanstalt, Braunschweig (Germany)

    1997-09-01

    Eurados Working Group 7 recently organised a large-scale comparison of neutron spectrometry and dosimetry measurements at the IPSN/SDOS laboratory of the CEA Cadarache Research Centre in France. A large number of participants took part with a range of instruments including spectrometers, tissue-equivalent proportional counters, personal dosemeters, and survey instruments. The neutron field used for the exercise was a primarily low energy neutron spectrum similar to those which have been measured recently around nuclear facilities. This paper presents the results of the measurements and attempts to draw conclusions about the accuracy attainable with the various devices, their advantages and drawbacks, and potential problems. (author).

  20. Influence of high permeability disks in an axisymmetric model of the Cadarache dynamo experiment

    CERN Document Server

    Giesecke, A; Stefani, F; Gerbeth, G; Léorat, J; Herreman, W; Luddens, F; Guermond, J -L

    2011-01-01

    Numerical simulations of the kinematic induction equation are performed on a model configuration of the Cadarache von-K\\'arm\\'an-Sodium dynamo experiment. The effect of a localized axisymmetric distribution of relative permeability {\\mu} that represents soft iron material within the conducting fluid flow is investigated. The critical magnetic Reynolds number Rm^c for dynamo action of the first non-axisymmetric mode roughly scales like Rm^c({\\mu})-Rm^c({\\mu}->infinity) ~ {\\mu}^(-1/2) i.e. the threshold decreases as {\\mu} increases. This scaling law suggests a skin effect mechanism in the soft iron disks. More important with regard to the Cadarache dynamo experiment, we observe a purely toroidal axisymmetric mode localized in the high permeability disks which becomes dominant for large {\\mu}. In this limit, the toroidal mode is close to the onset of dynamo action with a (negative) growth-rate that is rather independent of the magnetic Reynolds number. We qualitatively explain this effect by paramagnetic pumping...

  1. The solar heating system of the sport centre 'Guillamo Swimming Pool' in Sierre, Switzerland; Installation solaire thermique. Complexe sportif de la piscine de Guillamo - Rapport final

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2008-07-01

    This illustrated report for the Swiss Federal Office of Energy describes the refurbishment and the extension of the sport centre 'Guillamo Swimming Pool' in Sierre, Switzerland. The original building built in 1978 included three swimming pools (two indoor and one small outdoor). In 2005 a three-room fitness centre, a wellness centre and a bar were added to the compound and the old building and technical installations refurbished. At the same time a 591 m{sup 2} solar collector array was added. Unglazed selective solar absorbers were mounted on the 5{sup o} tilted flat roof. They insure at the same time the water tightness of the roof, a feature that lead to a significant cost reduction of the project. Before 2005 the natural gas consumption of the centre was 1.3 to 1.7 GWh/year. After the construction work the consumption was about 1.6 GWh, including a contribution of 0.06 GWh from the solar collectors. This last figure is disappointing. The reasons for this are mainly attributed by the authors to a very poor integration of the solar collectors into the conventional heat generation and distribution system, which do not enable the solar collectors to deliver the heat quantity they should. Changes should be made on the hydraulics of the whole system and on the control algorithms and settings.

  2. Geneva 24 Hours Swim

    CERN Multimedia

    2003-01-01

    The 18th edition of the Geneva 24 hours swim competition will take place at the Vernets Swimming Pool on the 4th and 5th of October. More information and the results of previous years are given at: http://www.carouge-natation.com/24_heures/home_24_heures.htm Last year, CERN obtained first position in the inter-company category with a total of 152.3 kms swam by 45 participants. We are counting on your support to repeat this excellent performance this year. For those who would like to train, the Livron swimming pool in Meyrin is open as from Monday the 8th September. For further information please do not hesitate to contact us. Gino de Bilio and Catherine Delamare

  3. Geneva 24 hours swim

    CERN Multimedia

    2003-01-01

    The 18th edition of the Geneva 24 hours swim competition will take place at the Vernets Swimming Pool on the 4th and 5th of October. More information and the results of previous years are given at: http://www.carouge-natation.com/24_heures/home_24_heures.htm Last year, CERN obtained first position in the inter-company category with a total of 152.3 kms swam by 45 participants. We are counting on your support to repeat this excellent performance this year. For those who would like to train, the Livron swimming pool in Meyrin is open as from Monday the 8th September. For further information please do not hesitate to contact us. Gino de Bilio and Catherine Delamare

  4. The RES reactor, a test reactor for naval propulsion; Le reacteur d'essais RES, reacteur d'essais de la propulsion navale

    Energy Technology Data Exchange (ETDEWEB)

    Pivet, S. [CEA Bruyeres-le-Chatel, 91 (France); Minguet, J.L. [AREVA-Technicatome, 13 - Aix en Provence (France)

    2005-07-01

    The RES, the new test reactor for naval propulsion, will replace the RNG that nears the end of its operating life after 30 years in service. The main asset of a land-based installation is to provide an in-core instrumented reactor while the on-board system must stay as simple as possible for robustness reasons. The objective of the RES is fivefold: 1) to foresee and help solving problems likely to happen on on-board reactor, 2) to validate nuclear fuels and reactor systems for naval propulsion, 3) to validate reactor system and equipment for the Barracuda submarine program, 4) to upgrade the on-ground facility located at Cadarache, and 5) to provide the Cea with a new capacity for the storing of spent fuels from naval propulsion systems and from Cea research reactors. The RES facility is made of 2 parts: one that houses the reactor and the other that is dedicated to the handling on spent fuels, their examination through a gamma spectrometry bench and their storing in a pool. The RES facility is scheduled to open in 2009. (A.C.)

  5. Emission and transmission tomography systems to be developed for the future needs of Jules Horowitz material testing reactor

    Energy Technology Data Exchange (ETDEWEB)

    Kotiluoto, Petri [VTT Technical Research Centre of Finland, P.O.Box 1000, FI-02044 VTT (Finland)], E-mail: petri.kotiluoto@vtt.fi; Wasastjerna, Frej; Kekki, Tommi [VTT Technical Research Centre of Finland, P.O.Box 1000, FI-02044 VTT (Finland); Sipilae, Heikki; Banzuzi, Kukka [Oxford Instruments Analytical Oy, Nihtisillankuja 5, P.O.Box 85, FI-02631 Espoo (Finland); Kinnunen, Petri; Heikinheimo, Liisa [VTT Technical Research Centre of Finland, P.O.Box 1000, FI-02044 VTT (Finland)

    2009-08-01

    The new 100 MW Jules Horowitz material testing reactor will be built in Cadarache, France. It will support, for instance, research on new types of innovative nuclear fuel. As a Finnish in-kind contribution, 3D emission and transmission tomography equipment will be delivered for both the reactor and the active component storage pool. The image reconstruction of activities inside the used nuclear fuel will be based on gamma spectrometry measurements. A new type of underwater digital X-ray linear detector array is under development for transmission imaging, based on GaAs and direct conversion of X-rays into an electrical signal. A shared collimator will be used for both emission and transmission measurements. Some preliminary design has been performed. For the current design, the expected gamma spectrometric response of a typical high-purity germanium detector has been simulated with MCNP for minimum and maximum source activities (specified by CEA) to be measured in future.

  6. Progressive Increase in Disinfection Byproducts and Mutagenicity from Source to Tap to Swimming Pool and Spa Water: Impact of Human Inputs.

    Science.gov (United States)

    Daiber, Eric J; DeMarini, David M; Ravuri, Sridevi A; Liberatore, Hannah K; Cuthbertson, Amy A; Thompson-Klemish, Alexis; Byer, Jonathan D; Schmid, Judith E; Afifi, Mehrnaz Z; Blatchley, Ernest R; Richardson, Susan D

    2016-07-01

    Pools and spas are enjoyed throughout the world for exercise and relaxation. However, there are no previous studies on mutagenicity of disinfected spa (hot tub) waters or comprehensive identification of disinfection byproducts (DBPs) formed in spas. Using 28 water samples from seven sites, we report the first integrated mutagenicity and comprehensive analytical chemistry of spas treated with chlorine, bromine, or ozone, along with pools treated with these same disinfectants. Gas chromatography (GC) with high-resolution mass spectrometry, membrane-introduction mass spectrometry, and GC-electron capture detection were used to comprehensively identify and quantify DBPs and other contaminants. Mutagenicity was assessed by the Salmonella mutagenicity assay. More than 100 DBPs were identified, including a new class of DBPs, bromoimidazoles. Organic extracts of brominated pool/spa waters were 1.8× more mutagenic than chlorinated ones; spa waters were 1.7× more mutagenic than pools. Pool and spa samples were 2.4 and 4.1× more mutagenic, respectively, than corresponding tap waters. The concentration of the sum of 21 DBPs measured quantitatively increased from finished to tap to pool to spa; and mutagenic potency increased from finished/tap to pools to spas. Mutagenic potencies of samples from a chlorinated site correlated best with brominated haloacetic acid concentrations (Br-HAAs) (r = 0.98) and nitrogen-containing DBPs (N-DBPs) (r = 0.97) and the least with Br-trihalomethanes (r = 0.29) and Br-N-DBPs (r = 0.04). The mutagenic potencies of samples from a brominated site correlated best (r = 0.82) with the concentrations of the nine HAAs, Br-HAAs, and Br-DBPs. Human use increased significantly the DBP concentrations and mutagenic potencies for most pools and spas. These data provide evidence that human precursors can increase mutagenic potencies of pools and spas and that this increase is associated with increased DBP concentrations.

  7. Successful scaling-up of self-sustained pyrolysis of oil palm biomass under pool-type reactor.

    Science.gov (United States)

    Idris, Juferi; Shirai, Yoshihito; Andou, Yoshito; Mohd Ali, Ahmad Amiruddin; Othman, Mohd Ridzuan; Ibrahim, Izzudin; Yamamoto, Akio; Yasuda, Nobuhiko; Hassan, Mohd Ali

    2016-02-01

    An appropriate technology for waste utilisation, especially for a large amount of abundant pressed-shredded oil palm empty fruit bunch (OFEFB), is important for the oil palm industry. Self-sustained pyrolysis, whereby oil palm biomass was combusted by itself to provide the heat for pyrolysis without an electrical heater, is more preferable owing to its simplicity, ease of operation and low energy requirement. In this study, biochar production under self-sustained pyrolysis of oil palm biomass in the form of oil palm empty fruit bunch was tested in a 3-t large-scale pool-type reactor. During the pyrolysis process, the biomass was loaded layer by layer when the smoke appeared on the top, to minimise the entrance of oxygen. This method had significantly increased the yield of biochar. In our previous report, we have tested on a 30-kg pilot-scale capacity under self-sustained pyrolysis and found that the higher heating value (HHV) obtained was 22.6-24.7 MJ kg(-1) with a 23.5%-25.0% yield. In this scaled-up study, a 3-t large-scale procedure produced HHV of 22.0-24.3 MJ kg(-1) with a 30%-34% yield based on a wet-weight basis. The maximum self-sustained pyrolysis temperature for the large-scale procedure can reach between 600 °C and 700 °C. We concluded that large-scale biochar production under self-sustained pyrolysis was successfully conducted owing to the comparable biochar produced, compared with medium-scale and other studies with an electrical heating element, making it an appropriate technology for waste utilisation, particularly for the oil palm industry.

  8. Neutronics and thermohydraulics of the reactor C.E.N.E. Part II; Analisis neutronico y termohidraulico del reactor C.E.N.E. Parte II

    Energy Technology Data Exchange (ETDEWEB)

    Caro, R.

    1976-07-01

    In this report the analysis of neutronics thermohydraulics and shielding of the 10 HWt swimming pool reactor C.E.N.E is included. In each of these chapters is given a short description of the theoretical model used, along with the theoretical versus experimental checking carried out, whenever possible, with the reactors JEN-I and JEN-II of Junta de Energia Nuclear. (Author) 11 refs.

  9. Neutronics and thermohydraulics of the reactor C.E.N.E.-Part I; Analisis neutronico y termohidraulico del reactor C.E.N.E. Parte I

    Energy Technology Data Exchange (ETDEWEB)

    Caro, R.; Ahnert, C.; Naudin, A. E.; Martinez Fanegas, R.; Minguez, E.; Rovira, A.

    1976-07-01

    In this report the analysis of neutronics (both statics and kinetics), of the 10 MWt swimming pool reactor C.E.N.E, is included. In each of these chapters is given a short description of the theoretical model used, along with the theoretical versus experimental checking, carried out, whenever possible, with the reactors JEN-I and JEN-II of Junta de Energia Nuclear. (Author) 11 refs.

  10. KROTOS FCI experimental programme at CEA Cadarache: new features and status

    Energy Technology Data Exchange (ETDEWEB)

    Bonnet, J.M.; Bullado, Y.; Journeau, C.; Fouquart, P.; Piluso, P.; Sergeant, C.; Magallon, D. [CEA-Cadarache, DTN/STRI/LMA, Bat 708, BP1, 13108 Saint Paul lez Durance cedex (France)

    2005-07-01

    Full text of publication follows: KROTOS facility has been operated by the European Commission at JRC-Ispra for many years until 1999 as part of the FARO/KROTOS programme. The programme had to be stopped at JRC due to new EC priorities, and an agreement was concluded with CEA to transfer the KROTOS facility and know-how to Cadarache to continue investigating the pending FCI issues. By this agreement, CEA became owner of the facility. The main objective of the KROTOS programme at CEA Cadarache is understanding the role of melt properties in steam explosion propagation and energetics and, in particular, steam explosion behaviour of prototypical corium melts. Possible influence of physicochemical processes on explosiveness will also be explored. Actually, analysis of alumina debris produced at Ispra have shown that formation of metastable phases and chemical reaction with water at high temperature may play a significant role in enhancing heat transfer to water in the explosion phase. In order to reach the objective, steam explosion experiments are performed in well characterised conditions for a large spectrum of conditions and melt compositions of interest for both in- and ex-vessel situations. A trigger is applied as a rule. Advanced technology and instrumentation is used to reduce uncertainties on initial conditions and characterise the various phases of an explosion, with emphasis on high energy X-ray cinematography to qualify pre-mixing. This advanced instrumentation will enable the measurement of detailed variables to consolidate the qualification of the FCI codes. The use of high energy X-rays made it necessary to construct a new building to house the facility and its components. The facility should newly become operative early 2005. Main improvements with respect to Ispra concern melt delivery, hydrogen measurement and X-ray imaging. Preliminary studies have demonstrated that identification of the pre-mixture-water interface and coherent melt jet core, and

  11. A model for the analysis of loss of decay heat removal during loss of coolant accident in MTR pool type research reactors

    Energy Technology Data Exchange (ETDEWEB)

    Bousbia-salah, Anis [Dipartimento di Ingegneria Meccanica, Nucleari e della Produzione, Facolta di Ingegneria, Universita di Pisa, Via Diotisalvi, 2, 56126 Pisa (Italy)]. E-mail: b.salah@ing.unipi.it; Meftah, Brahim [Division Reacteur - Centre de Recherche Nucleaire Draria (CRND), BP 43 Sebala DRARIA - Algiers (Algeria); Hamidouche, Tewfik [Laboratoire des Analyses de Surete, Centre de Recherche Nucleaire d' Alger (CRNA), 02 Boulevard Frantz Fanon, B.P. 399, 16000 Algiers (Algeria)]. E-mail: thamidouche@comena-dz.org; Si-Ahmed, El Khider [Laboratoire des Ecoulements Polyhpasiques, Universite des Sciences et de la Technologie d' Alger, Algiers (Algeria)

    2006-03-15

    During a loss of coolant accident leading to total emptying of the reactor pool, the decay heat could be removed through air natural convection. However, under partial pool emptying the core is partially submerged and the coolant circulation inside the fuel element could no more be possible. Under such conditions, a core overheat takes place, and the thermal energy is essentially diffused from the core to its periphery by combined thermal radiation and conduction. In order to predict fuel element temperature evolution under such conditions a mathematical model is performed. The model is based on a 3D geometry and takes into account a variety of core configurations including fuel elements (standard and control), reflector elements and grid plates. The homogeneous flow model is used and the fluid conservation equations are solved using a semi-implicit finite difference method. Preliminary tests of the developed model were made by considering a series of hypothetical accidents. In the current framework a loss of decay heat removal accidents in the IAEA benchmark open pool MTR-type research reactor is considered. It is shown that in the case of a low core immersion height no water boiling is observed and the fuel surface temperature rise remains below the melting point of the aluminium cladding.

  12. Web application for the control and management of radioprotection equipment in the Cadarache centre; Application WEB pour le controle et la gestion des appareils de radioprotection sur le centre de Cadarache

    Energy Technology Data Exchange (ETDEWEB)

    Anon.

    2010-07-01

    The author describes a web 2-type application which has been developed for the periodic calibration controls of radioprotection equipment in Cadarache. This application aims at offering an easy and immediate and even remote access to information, at selecting information with respect to uses (radioprotection department, administrator, and so on), at securing and safeguarding homogeneous data, at editing control statistics. The different functionalities are briefly presented with their displayed interface

  13. Activities for extending the lifetime of MINT research reactor

    Energy Technology Data Exchange (ETDEWEB)

    Bokhari, Adnan; Kassim, Mohammad Suhaimi [Malaysian Inst. for Nuclear Technology Research (MINT), Bangi, Kajang (Malaysia)

    1998-10-01

    MINT TRIGA Reactor is a 1-MW swimming pool nuclear reactor commissioned in June 1982. Since then, it has been used for research, isotope production, neutron activation, neutron radiography and manpower training. The total operating time till the end on September 1997 is 16968 hours with cumulative total energy release of 11188 MW-hours. After more than fifteen years of successful operation, some deterioration in components and associated systems has been observed. This paper describes some of the activities carried out to increase the lifetime and to reduce the shutdown time of the reactor. (author)

  14. 游泳水上训练计划计算机管理软件的设计与实现%Design and realization of software wizard for swimming pool training plan

    Institute of Scientific and Technical Information of China (English)

    白慕炜; 沈宇鹏; 张晓琳

    2012-01-01

    科学有效的游泳水上训练计划地制定和实施对提高游泳训练水平至关重要。目前,国内教练员训练计划制定和管理大都处于纸笔和word文档层次。本研究以ACCESS2003作为底层数据库,采用DELPH17.0编程,研制开发了游泳水上训练计划计算机管理软件。该软件具有辅助教练员完成训练计划制定、训练负荷统计、训练数据计算等多种功能,可帮助教练员制定、修改、查询及打印训练计划,可按年度、周期等自定义时间统计训练负荷。软件的开发弥补了国内还没有同类软件的不足,具有原创性价值,能帮助教练员在制定训练计划前掌握训练负荷信息,并在训练计划实施后,通过软件对训练负荷的统计有效的对训练计划进行评估和改进,从而提高游泳训练科学化和信息化管理水平。%The establishment and implementation of an effective and scientific training plan is of much importance for raising swimming training level. Most coaches in China establish and manage athletes training plan with traditional written documents. By taking ACCESS 2003 as database, this study adopted DELPHI 7.0 program to develop a software wizard for swimming pool training, with which the coaches could formulate, change, search and print training plans, as well as calculate training load at a user - defined term. Also, the software made up for the lack of such software in China. With the software, the coaches could learn about the training load before formulating a plan and evaluate and improve the plan after load calculation, so as to improve the management of swimming training scientifically.

  15. The RES Reactor. A test reactor for the French naval propulsion

    Energy Technology Data Exchange (ETDEWEB)

    Pivet, Sylvestre [CEA, Centre de Cadarache, F-13108 Saint Paul lez Durance (France); Minguet, Jean-Luc [AREVA-Technicatome, BP17, 91192 Gif-sur-Yvette (France)

    2006-07-01

    In the Cadarache nuclear research centre the French Atomic Energy Commission (CEA) operates, with the support of TECHNICATOME as nuclear operator, the experimental facilities which are necessary for the French naval propulsion program. Since the sixties these facilities have brought a large contribution to the development and to the technical support for the nuclear propulsion; they have been used also to train the French Navy operators. The last experimental reactor, the RNG, is now at the end of its life cycle after thirty years of a profitable operation. A replacement reactor is needed to sustain any evolution of the naval propulsion reactors as well as to guarantee a safe operation and a high level of availability of the existing onboard reactors. The aim of the RES program is namely to build such a test facility. Its construction program started in 2003. By the year 2009 the RES reactor will take over the mission of the RNG. We present hereafter: - A brief history of the French experimental reactors built in support to the naval propulsion, - The needs of the naval propulsion and the related objectives of the RES program, - The corresponding architecture and main characteristics of the RES facility, - The current status of the RES construction. The contents of the paper is as follows: 1. Introduction; 2. History of the French nuclear propulsion experimental reactors; 3. Needs of the naval propulsion and related objectives of the RES reactor; 4. RES architecture and main characteristics; 4.1. The pool module; 4.2. The reactor module; 4.3. The RES reactor, an innovative concept; 5. Realisation status; 6. Conclusion. To summarize, from the year 2009 the RES will be an efficient facility available for irradiation and qualification programs. Its large experimental capabilities will allow relevant fuel and core irradiations. This will give access to a real progress in the knowledge of fuel and core physics as well as in the related simulation tools. This reactor

  16. The use and evolution of the CEA research reactors; Utilisation et evolution des reacteurs de recherche du C.E.A

    Energy Technology Data Exchange (ETDEWEB)

    Rossillon, F.; Chauvez, C. [Commissariat a l' Energie Atomique, Saclay (France). Centre d' Etudes Nucleaires

    1964-07-01

    the behaviour of organic liquids under irradiation. The equipments of Melusine are now being modernized. Siloe, another swimming-pool reactor, has been operating at 15 MW since the end of 1963. The performances achieved constitute a considerable progress in the field of swimming-pool reactors, since the fluxes obtained with Siloe are in the same order of magnitude than those which needed till now a tank type structure, whose numerous disadvantages in the fitting of experiments are well known. Siloe will be used mostly in the study of structural materials, graphites, refractory fissile materials, and for solid state physics. The reactor Pegase, in service in the Cadarache Nuclear Centre since 1963, is intended solely for testing full-scale fuel elements of EDF and EL 4 types. The current programme, for the eight loops of the reactor, covers the elements for the reactors EDF 2, EDF 3 and EL 4. New loops are in the course of being studied for the fuel elements of the EDF 4 and EDF 5 reactors. The general line of the CEA programmes has shown up the considerable need for fast neutron irradiations. The reactor Osiris which is in the course of being constructed will serve to complement the CEA's equipment in this field and at the same time fill the gap which will be left in the near future in the Centre de Saclay by the closing down of EL 2. Osiris is a light water reactor whose special structure will allow it to function at 50 MW without the disadvantages usually associated with the presence of a heavy waterproof tank. This reactor, which should be put into service in 1966, is mainly intended for the investigation of structural materials, graphite and refractory fuels; it will also serve to increase the production of high specific activity isotopes, and to develop activation analysis techniques. (authors) [French] Les auteurs examinent successivement les differents reacteurs de recherche en service dans les Centres du Commissariat a l'Energie Atomique. Ils

  17. Application of passive energy conservation technique to a constant temperature indoor swimming pool%被动节能在某室内恒温游泳池中的应用

    Institute of Scientific and Technical Information of China (English)

    胡晨炯; 屈国伦; 胡婧; 林心关; 王飞; 刘后根; 常先问

    2012-01-01

    Introduces the natural ventilation system into the swimming pool design and determines the air inlet and outlet scheme based on CFD simulation results. Gives the logic decision conditions of natural ventilation operation, natural ventilation plus mechanical ventilation operation and air conditioning operation. Calculates the annual ventilation operation hours using the meteorological parameters of a typical year in Guangzhou and analyses the energy saving effect of ventilation operation by annual energy consumption simulation.%在该恒温游泳池设计中引入了自然通风系统,结合CFD模拟结果确定了进排风方案.给出了自然通风、自然通风与机械通风联合运行和空调运行的逻辑判-定条件.采用广州市典型气象年的气象资科计算了全年通风运行时间,并通过全年能耗模拟分析了其节能效益.

  18. Scaled Facility Design Approach for Pool-Type Lead-Bismuth Eutectic Cooled Small Modular Reactor Utilizing Natural Circulation

    Energy Technology Data Exchange (ETDEWEB)

    Park, Sangrok; Shin, Yong-Hoon; Lee, Jueun; Hwang, Il Soon [Seoul National University, Seoul (Korea, Republic of)

    2015-10-15

    In low carbon era, nuclear energy is the most prominent energy source of electricity. For steady ecofriendly nuclear energy supply, Generation IV reactors which are future nuclear reactor require safety, sustainability, economics and non-proliferation as four criteria. Lead cooled fast reactor (LFR) is one of these reactor type and Generation IV international forum (GIF) adapted three reference LFR systems which are a small and movable systems with long life without refueling, intermediate size and huge electricity generation system for power grid. NUTRECK (Nuclear Transmutation Energy Center of Korea) has been designed reactor called URANUS (Ubiquitous, Rugged, Accident-forgiving, Non-proliferating, and Ultra-lasting Sustainer) which is small modular reactor and using lead-bismuth eutectic coolant. To prove natural circulation capability of URANUS and analyze design based accidents, scaling mock-up experiment facility will be constructed. In this paper, simple specifications of URANUS will be presented. Then based on this feature, scaling law and scaled facility design results are presented. To validate safety feature and thermodynamics characteristic of URANUS, scaled mockup facility of URANUS is designed based on the scaling law. This mockup adapts two area scale factors, core and lower parts of mock-up are scaled for 3D flow experiment. Upper parts are scaled different size to reduce electricity power and LBE tonnage. This hybrid scaling method could distort some thermal-hydraulic parameters, however, key parameters for experiment will be matched for up-scaling. Detailed design of mock-up will be determined through iteration for design optimization.

  19. Vortices revealed: Swimming faster

    Science.gov (United States)

    van Houwelingen, Josje; van de Water, Willem; Kunnen, Rudie; van Heijst, Gertjan; Clercx, Herman

    2016-11-01

    Understanding and optimizing the propulsion in human swimming requires insight into the hydrodynamics of the flow around the swimmer. Experiments and simulations addressing the hydrodynamics of swimming have been conducted in studies before, including the visualization of the flow using particle image velocimetry (PIV). The main objective in this study is to develop a system to visualize the flow around a swimmer in practice inspired by this technique. The setup is placed in a regular swimming pool. The use of tracer particles and lasers to illuminate the particles is not allowed. Therefore, we choose to work with air bubbles with a diameter of 4 mm, illuminated by ambient light. Homogeneous bubble curtains are produced by tubes implemented in the bottom of the pool. The bubble motion is captured by six cameras placed in underwater casings. A first test with the setup has been conducted by pulling a cylinder through the bubbles and performing a PIV analysis. The vorticity plots of the resulting data show the expected vortex street behind the cylinder. The shedding frequency of the vortices resembles the expected frequency. Thus, it is possible to identify and follow the coherent structures. We will discuss these results and the first flow measurements around swimmers.

  20. The JHR reactor: a multipurpose asset for materials; Le reacteur RHJ: polyvalence au service des materiaux

    Energy Technology Data Exchange (ETDEWEB)

    Iracane, D.; Yvon, P. [CEA Saclay, Dir. de l' Energie Nucleaire, 91 - Gif sur Yvette (France)

    2007-07-01

    The creeping obsolescence of experimental irradiation reactors around the world, in the European Union in particular, means that the Jules Horowitz Reactor (JHR), due to be commissioned by CEA in 2014, at Cadarache, is an essential addition, whether it be for the investigation of materials, or of novel fuels. Its capabilities extend beyond the requirements of investigations relating to fourth-generation systems. (authors)

  1. Rapport d'étude : La perception des risques majeurs par les riverains du CEA de Cadarache

    OpenAIRE

    Lopez, Alexia; Régner, Isabelle; Schleyer-Lindenmann, Alexandra

    2015-01-01

    Ce rapport d'étude vient répondre aux interrogations de son commanditaire, la CLI (Commission Local d'Information) du CEA (Commissariat à l'énergie Atomique) de Cadarache. Il s'organise en trois partie : une première partie établit un état des lieux des connaissances des risques majeurs par les habitants. Les risques majeurs officiellement recensés sont : le risque feu de forêt, le risque inondation, le risque sismique, le risque de mouvement de terrain, le risque de rupture de barrage, et le...

  2. 用于池式快堆系统分析的钠池三维模型开发%Development of Three-Dimensional Sodium Pool Model for System Analysis of Pool-Type Liquid Metal Fast Breeder Reactor

    Institute of Scientific and Technical Information of China (English)

    隋丹婷; 陆道纲; 张盼

    2012-01-01

    由于池式快堆钠池内的热工水力学特性对反应堆的安全运行有重要影响,本文采用基于交错网格的SIMPLE算法开发直角坐标系和柱坐标系下钠池三维计算软件.应用CFX软件进行验证之后,完成了三维流场分析程序与系统分析软件SAC-CFR的耦合,并用耦合后的程序分析日本文殊快堆45%功率稳态运行工况上腔室内的流场分布,初步验证了堆芯上腔三维化的SAC-CFR用于系统分析的有效性,为进一步开发事故模型、非能动余热排出系统模型做准备.%As the thermal-hydraulic characteristic in sodium pool is crucial for safety operation of liquid metal fast breeder reactor (LMFBR), a three-dimensional sodium pool thermal-hydraulic analysis code was developed based on SIMPLE algorithm on stagger grid under Cartesian coordinates and cylindrical coordinates. After the validation with CFX, coupling between the analysis code and SAC-CFR was completed) and then the coupled code was applied to the flow field analysis in upper plenum of Monju Plant at 45% thermal power steady-state operation condition, which preliminary shows the effectiveness of the system analysis with coupled code and makes preparations for further development of accident analysis model and passive residual heat removal system.

  3. Fuel shuffling optimization for the Delft research reactor

    Energy Technology Data Exchange (ETDEWEB)

    Geemert, R. van; Hoogenboom, J.E.; Gibcus, H.P.M. [Delft Univ. of Technology, Interfaculty Reactor Inst., Delft (Netherlands); Quist, A.J. [Delft Univ., Fac. of Applied Mathematics and Informatics, Delft (Netherlands)

    1997-07-01

    A fuel shuffling optimization procedure is proposed for the Hoger Onderwijs Reactor (HOR) in Delft, the Netherlands, a 2 MWth swimming-pool type research reactor. In order to cope with the fluctuatory behaviour of objective functions in loading pattern optimization, the proposed cyclic permutation optimization procedure features a gradual transition from global to local search behaviour via the introduction of stochastic tests for the number of fuel assemblies involved in a cyclic permutation. The possible objectives and the safety and operation constraints, as well as the optimization procedure, are discussed, followed by some optimization results for the HOR. (author)

  4. Swimming Droplets

    Science.gov (United States)

    Maass, Corinna C.; Krüger, Carsten; Herminghaus, Stephan; Bahr, Christian

    2016-03-01

    Swimming droplets are artificial microswimmers based on liquid droplets that show self-propelled motion when immersed in a second liquid. These systems are of tremendous interest as experimental models for the study of collective dynamics far from thermal equilibrium. For biological systems, such as bacterial colonies, plankton, or fish swarms, swimming droplets can provide a vital link between simulations and real life. We review the experimental systems and discuss the mechanisms of self-propulsion. Most systems are based on surfactant-stabilized droplets, the surfactant layer of which is modified in a way that leads to a steady Marangoni stress resulting in an autonomous motion of the droplet. The modification of the surfactant layer is caused either by the advection of a chemical reactant or by a solubilization process. Some types of swimming droplets possess a very simple design and long active periods, rendering them promising model systems for future studies of collective behavior.

  5. The Effective Convectivity Model for Simulation and Analysis of Melt Pool Heat Transfer in a Light Water Reactor Pressure Vessel Lower Head

    Energy Technology Data Exchange (ETDEWEB)

    Tran, Chi Thanh

    2009-09-15

    Severe accidents in a Light Water Reactor (LWR) have been a subject of intense research for the last three decades. The research in this area aims to reach understanding of the inherent physical phenomena and reduce the uncertainties in their quantification, with the ultimate goal of developing models that can be applied to safety analysis of nuclear reactors, and to evaluation of the proposed accident management schemes for mitigating the consequences of severe accidents. In a hypothetical severe accident there is likelihood that the core materials will be relocated to the lower plenum and form a decay-heated debris bed (debris cake) or a melt pool. Interactions of core debris or melt with the reactor structures depend to a large extent on the debris bed or melt pool thermal hydraulics. In case of inadequate cooling, the excessive heat would drive the structures' overheating and ablation, and hence govern the vessel failure mode and timing. In turn, threats to containment integrity associated with potential ex-vessel steam explosions and ex-vessel debris uncoolability depend on the composition, superheat, and amount of molten corium available for discharge upon the vessel failure. That is why predictions of transient melt pool heat transfer in the reactor lower head, subsequent vessel failure modes and melt characteristics upon the discharge are of paramount importance for plant safety assessment. The main purpose of the present study is to develop a method for reliable prediction of melt pool thermal hydraulics, namely to establish a computational platform for cost-effective, sufficiently-accurate numerical simulations and analyses of core Melt-Structure-Water Interactions in the LWR lower head during a postulated severe core-melting accident. To achieve the goal, an approach to efficient use of Computational Fluid Dynamics (CFD) has been proposed to guide and support the development of models suitable for accident analysis. The CFD method, on the one hand

  6. 300#堆燃料组件运行历史数据库%Database of Operation History for Fuel Elements in Swimming Pool Research Reactor 300

    Institute of Scientific and Technical Information of China (English)

    陈炜; 蒋砚伟

    2006-01-01

    为了配合ORIGEN2计算原始数据准备,采用Microsoft Access建立300#堆运行历史数据库.简化后只用一个表记录反应堆的运行历史.每盒燃料组件的表单只记录其经历的装载历史,最多不超过20条.表单之间用字段"装载ID"联接.对统计和录入中可能出现的两类错误,各建立一个查询,用于自动检索错误.对每盒燃料组件,建立查询,根据组件装载历史表单从总反应堆运行历史表单中采集数据,并将数据以文件文件形式输出,用编制的运行历史数据处理程序,将数据转换为0RIGEN2计算需要的运行历史输入数据.

  7. Web software for the control and management of radiation protection devices in the Cadarache site; Application WEB pour le controle et la gestion des appareils de radioprotection sur le centre de Cadarache

    Energy Technology Data Exchange (ETDEWEB)

    Beltritti, F. [CEA Cadarache 13108 St Paul lez Durance Cedex (France)

    2010-07-01

    This series of slides presents how to use a new software dedicated to the management of the periodical controls that have to be performed on the equipment involved in radiation protection. This software is ready to be dispatched on the CEA site of Cadarache. This software gives information on: the device to be controlled, the controls that have to be performed, the procedures to follow to make the test, the equipment necessary for the test particularly the need for radioactive sources, the maintenance of the device, the previous measurements and in the end the device's conformity. An evaluation of the conformity of all the devices present in a building or an area or of a particular type can be easily obtained. (A.C.)

  8. Strategies for chemically healthy public swimming pools

    OpenAIRE

    Hansen, Kamilla Marie Speht; Andersen, Henrik Rasmus; Albrechtsen, Hans-Jørgen; Mosbæk, Hans

    2013-01-01

    I Danmark er offentlige svømmebade en vigtig mulighed for rekreative aktiviteter og fysisk træning samt et redskab for genoptræning. Tilsætning af klor anvendes altid til at kontrollere vand¬kvaliteten og hindre spredning af infektioner mellem badende. Klor oxiderer vandforureningen fra de badende, hvilket holder bassinvandet rent, men der dannes klorerede desinfektions¬biprodukter. Der er identificeret mere end 100 klorbiprodukter i svømme¬bads¬vand, hvor nogle har vist sig at være genotoksi...

  9. Proposal of novel method of continuous monitoring of possible fuel failure of a pool-type reactor

    Energy Technology Data Exchange (ETDEWEB)

    Sasaki, K. [Rikkyo University, Nishi-Ikebukuro, Toshima-ku, Tokyo (Japan). College of Science; Hayashi, S.A.; Matsura, T. [Rikkyo University, Nagasaka, Yokosuka (Japan). Institute for Atomic Energy

    1997-10-01

    During the course of studies on fuel failure detection, we have found that the bubbling of a gas such as nitrogen into a reactor coolant water effectively purges the dissolved fission rare gases ({sup 89}Kr, T{sub 1/2}=3.15 min, and {sup 138}Xe, T{sub 1/2}=14.08 min) and that the respective daughter nuclides ({sup 89}Rb, T{sub 1/2}=15.15 min and {sup 138}Cs, T{sub 1/2}=33.41 min) are detected in the washing water of the collected gas mixture. The detected activity depends on the time of standing between sampling and washing of the gas, and the dependence agreed well with the theoretical prediction from the consecutive radioactive decay for both pairs ({sup 89}Kr-{sup 89}Rb, and {sup 138}Xe-{sup 138}Cs). Based on these findings, we have recently constructed a semi-continuous fuel monitoring system, which consists of an automatic and intermittent gas sampler (1 litre bottles) and a bottle conveying unit. After standing for a definite time, bottled gas is shaken with a small amount of water, and the activity of the water is measured. This system operates satisfactorily, but the whole system involves several sophisticated steps so that is rather costly. Quite recently we have got an idea of a simpler, more economical, fully automated continuous system. The system consists in principle only of a large cylinder with packing materials just as in a fractional distiller. On the top of the cylinder there are an inlet of washing water and an outlet of the gas, and at the bottom there are an inlet of the collected gas from the coolant and an outlet of the washing water. The whole system can be operated fully automatically and continuously, with continuous feeding of bubbling gas into the reactor coolant. This has not yet been experimentally tested at present, and in this presentation, information about the setup parameters such as the flow rate of the bubbling gas, the volume of the cylinder and vacant space, the flow rate of the washing water, etc. are reported

  10. The Good, the Bad, and the Volatile - Can We Have Both Healthy Pools and Healthy People?

    Science.gov (United States)

    Given the popularity of swimming for recreation and sport, it is remarkable that we are only in the early stages of understanding swimming pool chemistry, human exposure(s), and potential health risks. This is partly due to the complexity of swimming pool water chemistry, which i...

  11. Is swimming during pregnancy a safe exercise?

    DEFF Research Database (Denmark)

    Juhl, Mette; Kogevinas, Manolis; Andersen, Per Kragh;

    2010-01-01

    BACKGROUND: Exercise in pregnancy is recommended in many countries, and swimming is considered by many to be an ideal activity for pregnant women. Disinfection by-products in swimming pool water may, however, be associated with adverse effects on various reproductive outcomes. We examined...... the association between swimming in pregnancy and preterm and postterm birth, fetal growth measures, small-for-gestational-age, and congenital malformations. METHODS: We used self-reported exercise data (swimming, bicycling, or no exercise) that were prospectively collected twice during pregnancy for 74......,486 singleton pregnancies. Recruitment to The Danish National Birth Cohort took place 1996-2002. Using Cox, linear and logistic regression analyses, depending on the outcome, we compared swimmers with physically inactive pregnant women; to separate a possible swimming effect from an effect of exercise...

  12. Simulation of decay heat removal by natural convection in a pool type fast reactor model-ramona-with coupled 1D/2D thermal hydraulic code system

    Energy Technology Data Exchange (ETDEWEB)

    Kasinathan, N.; Rajakumar, A.; Vaidyanathan, G.; Chetal, S.C. [Indira Gandhi Centre for Atomic Research, Kalpakkam (India)

    1995-09-01

    Post shutdown decay heat removal is an important safety requirement in any nuclear system. In order to improve the reliability of this function, Liquid metal (sodium) cooled fast breeder reactors (LMFBR) are equipped with redundant hot pool dipped immersion coolers connected to natural draught air cooled heat exchangers through intermediate sodium circuits. During decay heat removal, flow through the core, immersion cooler primary side and in the intermediate sodium circuits are also through natural convection. In order to establish the viability and validate computer codes used in making predictions, a 1:20 scale experimental model called RAMONA with water as coolant has been built and experimental simulation of decay heat removal situation has been performed at KfK Karlsruhe. Results of two such experiments have been compiled and published as benchmarks. This paper brings out the results of the numerical simulation of one of the benchmark case through a 1D/2D coupled code system, DHDYN-1D/THYC-2D and the salient features of the comparisons. Brief description of the formulations of the codes are also included.

  13. RJH, a new test reactor in Europe; Le RJH - un nouveau reacteur d'essai en europe

    Energy Technology Data Exchange (ETDEWEB)

    Iracane, D. [CEA Saclay, Dir. de l' Energie Nucleaire (DEN), 91 - Gif sur Yvette (France)

    2005-07-01

    Material test reactors (MTR) are now ageing in Europe and they cannot secure the experimental needs over next decades. In this context, a new MTR, named Jules Horowitz reactor (RJH), operated as an international user-facility, is under development on the Cea's site of Cadarache (France). The design studies will end in 2007, the construction stage will follow and RJH commissioning is scheduled in 2014. Its construction costs are estimated to 500 million euros. RJH is a pool reactor of 100 MWth, its core will be inserted in a pressurized vessel with a primary circuit assuring water flow through forced convection. The core inlet-outlet temperature is about 25-40 Celsius degrees. RJH core is designed to use a high density - low enrichment UMo nuclear fuel (8 gU/cm{sup 3}, enrichment rate: 19.75%). Experimental devices located in the core will benefit from neutron fluxes ranging from 2.5 10{sup 14} n/cm{sup 2}.s to 5.10{sup 14} n/cm{sup 2}.s (E > 1 MeV). RJH is designed to manage simultaneously 10 experiments in the core and as many in the reflector. (A.C.)

  14. Reactor

    Science.gov (United States)

    Evans, Robert M.

    1976-10-05

    1. A neutronic reactor having a moderator, coolant tubes traversing the moderator from an inlet end to an outlet end, bodies of material fissionable by neutrons of thermal energy disposed within the coolant tubes, and means for circulating water through said coolant tubes characterized by the improved construction wherein the coolant tubes are constructed of aluminum having an outer diameter of 1.729 inches and a wall thickness of 0.059 inch, and the means for circulating a liquid coolant through the tubes includes a source of water at a pressure of approximately 350 pounds per square inch connected to the inlet end of the tubes, and said construction including a pressure reducing orifice disposed at the inlet ends of the tubes reducing the pressure of the water by approximately 150 pounds per square inch.

  15. Evaluation of the aptitude for the service of the pool of the TRIGA Mark III reactor of the National Institute of Nuclear Research of Mexico; Evaluacion de la aptitud para el servicio de la piscina del reactor TRIGA Mark III del Instituto Nacional de Investigaciones Nucleares de Mexico

    Energy Technology Data Exchange (ETDEWEB)

    Merino C, J.; Gachuz M, M.; Diaz S, A.; Arganis J, C.; Gonzalez R, C.; Nava G, T.; Medina R, M.J. [Departamento de Sintesis y Caracterizacion de Materiales del ININ, A.P. 18-1027, 11801 Mexico D.F. (Mexico)

    2001-07-01

    This work describes the evaluation of the structural integrity of the pool of the TRIGA Mark III reactor of the National Institute of Nuclear Research of Mexico, which was realized in July 2001, as an element to determine those actions for preventive and corrective maintenance which owner must do it for a safety and efficient operation of the component in the next years. (Author)

  16. Protocol of actuation before occurrence of 'molluscum contagiosum' for use in public swimming pools Protocolo de actuación ante la aparición de casos de molusco contagioso en piscinas de uso público

    Directory of Open Access Journals (Sweden)

    José Ángel Bautista Cotorruelo

    2008-12-01

    Full Text Available The main objective is to develop a protocol for the disinfection of episodes of Molluscum contagiosum and establish an objective indicator. Molluscum contagiosum is a virus of Poxviridae Family. This virus produces a common infection in children that occurs when they come into direct contact with a lesion or with contaminated objects. In November 2008 is received at the Servicio de Sanidad Ambiental (Dirección General de Salud Pública, Consejería de Sanidad y Consumo, Comunidad Autónoma de la Región de Murcia a telephone call from the Epidemiology Service, which reported the existence of about 12-15 cases of children affected by Molluscum contagiosum. In addition, they indicated us that the suspicions fell on the Municipal Pool Cover Alhama de Murcia. Immediately we contacted the responsible staff and we send them a protocol developed with information from several sources. The analysis of articles used for water activities showed absence of Molluscum contagiosum. We selected "absence of molds and yeasts” as indicator. All this coincided with the disappearance of the cases. Months later, in March 2009 we detected new cases of children affected in another pool in the town of Alcantarilla. Due to the success of the methodology used in the earlier incident we performed the same actions and we obtained the same results. The protocol developed by this Service is effective to avoid the occurrence of more cases. We propose the “absence of molds and yeasts” as an indicator to evaluate the presence of Molluscum contagiosum. Coinciding with the update of the rules of public swimming pools in our Region we have introduced an article that indicates that the objects used for water activities must be disinfected after each use.El objetivo principal fue elaborar un protocolo de actuación para el caso de episodios de infección de molusco contagioso y un indicador objetivo, que nos permita hacer un seguimiento. El virus del molusco contagioso

  17. Jules Horowitz Reactor, basic design

    Energy Technology Data Exchange (ETDEWEB)

    Bergamaschi, Y.; Bouilloux, Y.; Chantoin, P.; Guigon, B.; Bravo, X.; Germain, C.; Rommens, M.; Tremodeux, P

    2003-07-01

    Since the shutdown of the SILOE reactor in 1997, the OSIRIS reactor has ensured the needs regarding technological irradiation at CEA including those of its industrial partners and customers. The Jules Horowitz Reactor will replace it. It has the ambition to provide the necessary nuclear data and maintain a fission research capacity in Europe after 2010. This capacity should be service-oriented. It will be established in Cadarache. The Jules Horowitz reactor will also: - represent a significant step in term of performances and experimental capabilities, - be designed with a high flexibility, in order to satisfy the current demand from European industry, research and be able to accommodate future requirements, - reach a high level of safety, according to the best current practice. This paper will present the main functionalities and the design options resulting from the 'preliminary design' studies. (authors)

  18. Efeitos de oito semanas de treinamento de natação no limiar anaeróbio determinado na piscina e no ergômetro de braço Effect of eight weeks of swimming training on the anaerobic threshold determined in the swimming pool and by arm ergometer

    Directory of Open Access Journals (Sweden)

    Fabrizio Caputo

    2002-02-01

    Full Text Available O objetivo deste estudo foi analisar os efeitos do treinamento de natação na intensidade do limiar anaeróbio (LAn, determinado na piscina e no ergômetro de braço, verificando se este pode ser utilizado para avaliar os efeitos do treinamento em nadadores. Participaram do estudo sete nadadores de ambos os sexos, com nível de performance regional, que foram submetidos aos seguintes testes, antes e após oito semanas de treinamento: 1 dois tiros de 400m, um a 85% e outro a 95% do máximo, com coleta de 25mil de sangue do lóbulo da orelha no 1º, 3º e 5º minuto após cada tiro, para posterior análise do lactato sanguíneo (YSI 1500; 2 teste contínuo progressivo realizado no ergômetro de braço (UBE 2462 Cybex, com carga inicial de 33,3W e incrementos de 16,6W a cada três minutos até a exaustão voluntária, com coleta de sangue ao final de cada estágio. Um grupo controle de indivíduos não ativos (n = 9, que se manteve sedentário, realizou somente o procedimento 2 no mesmo intervalo de tempo. O LAn na natação (NLAn e no ergômetro de braço (BLAn foi encontrado através de interpolação linear, considerando uma concentração fixa de lactato de 4mM e 3,5mM, respectivamente. Os resultados demonstram diferença significante para o grupo treinado, entre o pré (130,4 ± 20,4W e o pós-teste (137,7 ± 17,9W para o BLAn. Porém, não foi encontrada diferença significante para o NLAn (1,09 ± 0,1m.s-1 e 1,13 ± 0,1m.s-1, p = 0,06. No grupo controle não foi encontrada diferença para o BLAn entre o pré (93,2 ± 11,5W e o pós-teste (87,7 ± 7,2W. Pode-se concluir através desses dados que a determinação do LAn no ergômetro de braço é útil para detectar adaptações na capacidade aeróbia de nadadores com nível de performance regional.The objective of this study was to analyze the effect of swimming training on the intensity corresponding to the anaerobic threshold (AnT determined in the swimming pool and by arm ergometer, and

  19. Coccomyxa actinabiotis sp. nov. (Trebouxiophyceae, Chlorophyta), a new green microalga living in the spent fuel cooling pool of a nuclear reactor.

    Science.gov (United States)

    Rivasseau, Corinne; Farhi, Emmanuel; Compagnon, Estelle; de Gouvion Saint Cyr, Diane; van Lis, Robert; Falconet, Denis; Kuntz, Marcel; Atteia, Ariane; Couté, Alain

    2016-10-01

    Life can thrive in extreme environments where inhospitable conditions prevail. Organisms which resist, for example, acidity, pressure, low or high temperature, have been found in harsh environments. Most of them are bacteria and archaea. The bacterium Deinococcus radiodurans is considered to be a champion among all living organisms, surviving extreme ionizing radiation levels. We have discovered a new extremophile eukaryotic organism that possesses a resistance to ionizing radiations similar to that of D. radiodurans. This microorganism, an autotrophic freshwater green microalga, lives in a peculiar environment, namely the cooling pool of a nuclear reactor containing spent nuclear fuels, where it is continuously submitted to nutritive, metallic, and radiative stress. We investigated its morphology and its ultrastructure by light, fluorescence and electron microscopy as well as its biochemical properties. Its resistance to UV and gamma radiation was assessed. When submitted to different dose rates of the order of some tens of mGy · h(-1) to several thousands of Gy · h(-1) , the microalga revealed to be able to survive intense gamma-rays irradiation, up to 2,000 times the dose lethal to human. The nuclear genome region spanning the genes for small subunit ribosomal RNA-Internal Transcribed Spacer (ITS) 1-5.8S rRNA-ITS2-28S rRNA (beginning) was sequenced (4,065 bp). The phylogenetic position of the microalga was inferred from the 18S rRNA gene. All the revealed characteristics make the alga a new species of the genus Coccomyxa in the class Trebouxiophyceae, which we name Coccomyxa actinabiotis sp. nov.

  20. An Account of Oak Ridge National Laboratory's Thirteen Research Reactors

    Energy Technology Data Exchange (ETDEWEB)

    Rosenthal, Murray Wilford [ORNL

    2009-08-01

    The Oak Ridge National Laboratory has built and operated 13 nuclear reactors in its 66-year history. The first was the graphite reactor, the world's first operational nuclear reactor, which served as a plutonium production pilot plant during World War II. It was followed by two aqueous-homogeneous reactors and two red-hot molten-salt reactors that were parts of power-reactor development programs and by eight others designed for research and radioisotope production. One of the eight was an all-metal fast burst reactor used for health physics studies. All of the others were light-water cooled and moderated, including the famous swimming-pool reactor that was copied dozens of times around the world. Two of the reactors were hoisted 200 feet into the air to study the shielding needs of proposed nuclear-powered aircraft. The final reactor, and the only one still operating today, is the High Flux Isotope Reactor (HFIR) that was built particularly for the production of californium and other heavy elements. With the world's highest flux and recent upgrades that include the addition of a cold neutron source, the 44-year-old HFIR continues to be a valuable tool for research and isotope production, attracting some 500 scientific visitors and guests to Oak Ridge each year. This report describes all of the reactors and their histories.

  1. A Swimming Competition

    Institute of Scientific and Technical Information of China (English)

    邹成兵; 邓新华

    2004-01-01

    Last Sunday, there was a swimming competition in our school. It had been a short time since I learned how to swim. Mr. Zhang, our PE teacher, said I had a gift in swimming and that competing in the game would help build up my confidence and courage. With his encouragement,I signed up for the swimming race.

  2. PROPERTIES OF SWIMMING WATER

    Directory of Open Access Journals (Sweden)

    Tayfun KIR

    2004-10-01

    Full Text Available Swimming waters may be hazardous on human health. So, The physicians who work in the facilities, which include swimming areas, are responsible to prevent risks. To ensure hygiene of swimming water, European Swimming Water Directive offers microbiological, physical, and chemical criteria. [TAF Prev Med Bull 2004; 3(5.000: 103-104

  3. PROPERTIES OF SWIMMING WATER

    OpenAIRE

    Tayfun KIR; Zakir COBANOÐLU

    2004-01-01

    Swimming waters may be hazardous on human health. So, The physicians who work in the facilities, which include swimming areas, are responsible to prevent risks. To ensure hygiene of swimming water, European Swimming Water Directive offers microbiological, physical, and chemical criteria. [TAF Prev Med Bull 2004; 3(5.000): 103-104

  4. No gender difference in peak performance in ultra-endurance swimming performance - analysis of the 'Zurich 12-h Swim' from 1996 to 2010.

    Science.gov (United States)

    Eichenberger, Evelyn; Knechtle, Beat; Rüst, Christoph Alexander; Christoph, Alexander Rüst; Knechtle, Patrizia; Lepers, Romuald; Rosemann, Thomas

    2012-10-31

    The aims of the study were to [1] investigate the performance trends at the 'Zurich 12-h Swim' in Switzerland from 1996 to 2010; and [2] determine the gender difference in peak performance in ultraendurance swimming. In total, 113 male and 53 female swimmers competed in this indoor ultraendurance event while swimming in a heated pool. The number of male participants significantly increased (r² = 0.36, P = 0.04) over time while the participation of females remained unchanged (r² = 0.12, P = 0.26). In the age group swimming performances (P swim performances remained unchanged across the years. Females are able to achieve a similar swim performance in an indoor ultra-endurance swim event of ~40 km. Further studies are needed to investigate whether females are able to achieve similar or even better performances than males in openwater ultra-swimming events such as 'Channel Swimming'.

  5. EFFECTS OF THREE FEEDBACK CONDITIONS ON AEROBIC SWIM SPEEDS

    Directory of Open Access Journals (Sweden)

    Pedro Pérez Soriano

    2009-03-01

    Full Text Available The purpose of this study was twofold: (a to develop an underwater chronometer capable to provide feedback while the athlete is swimming, as well as being a control tool for the coach, and (b to analyse its feedback effect on swim pace control compared with feedback provided by the coach and with no feedback, in 25 m and 50 m swimming pools. 30 male swimmers of national level volunteer to participate. Each swimmer swam 3 x 200 m at aerobic speed (AS and 3 x 200 m just under the anaerobic threshold speed (AnS, each swam repetition with a different feedback condition: chronometer, coach and without feedback. Results (a validate the chronometer system developed and (b show that swimmers pace control is affected by the type of feedback provided, the swim speed elected and the size of the swimming pool

  6. Teaching Sodium Fast Reactor Technology and Operation for the Present and Future Generations of SFR Users

    OpenAIRE

    Christian, Latge; Rodriguez, Gilles; Baque, Francois; Leclerc, Arnaud; Martin, Laurent; Vray, Bernard; Romanetti, Pascale

    2011-01-01

    International audience; This paper provides a description of the education and training activities related to sodium fast reactors, carried out respectively in the French Sodium and Liquid Metal School (ESML) created in 1975 and located in France (at the CEA Cadarache Research Centre), in the Fast Reactor Operation and Safety School (FROSS) created in 2005 at the Phenix plant, and in the Institut National des Sciences et Techniques Nucle'aires (INSTN). It presents their recent developments an...

  7. Swimming Safely (A Minute of Health with CDC)

    Centers for Disease Control (CDC) Podcasts

    2014-05-22

    Almost 4,000 people die from drowning each year in the U.S. You can also get sick at the pool. This podcast discusses swimming pool safety tips.  Created: 5/22/2014 by MMWR.   Date Released: 5/22/2014.

  8. SWIMMING CLASSES IN JUNIOR HIGH SCHOOL STUDENTS’ OPINION

    Directory of Open Access Journals (Sweden)

    Grzegorz Bielec

    2013-02-01

    Full Text Available The role of modern physical education is not only to develop motor abilities of the students, but most of all prevent them from epidemic youth diseases such as obesity or postural defects. Positive attitudes to swimming as a long-life physical activity, instilled in adolescence should be beneficial in adult life. The group of 130 boys and 116 girls of 7th grade junior high school (mean age 14.6 was asked in the survey to present their opinion of obligatory swimming lessons at school. Students of both sexes claimed that they liked swimming classes because they could improve their swimming skills (59% of answers and because of health-related character of water exercises (38%. 33% of students regarded swimming lessons as boring and monotonous, and 25% of them complained about poor pool conditions like chlorine smell, crowded lanes, too low temperature. Majority of the surveyed students saw practical role of swimming in saving others life.

  9. Laryngoscopy during swimming

    DEFF Research Database (Denmark)

    Walsted, Emil S; Swanton, Laura L; van van Someren, Ken

    2017-01-01

    that precipitates their symptoms. This report provides the first description of the feasibility of performing continuous laryngoscopy during exercise in a swimming environment. The report describes the methodology and safety of the use of continuous laryngoscopy while swimming. Laryngoscope, 2017....

  10. ARC Code TI: Swim

    Data.gov (United States)

    National Aeronautics and Space Administration — Swim is a software information service for the grid built on top of Pour, which is an information service framework developed at NASA. Swim provides true software...

  11. SAFETY AND MANAGEMENT OF SWIMING POOLS

    Directory of Open Access Journals (Sweden)

    Cemal GÜNDOĞDU

    2008-04-01

    Full Text Available In this study,it was investigated the situation related to the safety and management of swimming pools belongs to municipality This study was planned to determine the present situation related to the safety and management of open,half-olympic and closed swimming pools which are especially used for sports activities,to find out the deficiencies in practise and to overcome these.Our study included totally 80 open,closed,olympic, half-olympic public swimming pools(the pools that belongs to municipality,private administration and university,the colleges connected to the ministry of education, Military schools and police college.In our research,search,natural observation and meeting methods were used.In accordance with this aim the checklist questions,which were prepared for health and safety controls in swimming pools, were tested on the people by face-to-face meeting method. While the statistical evaluation of the available results were being done,frequency and percentage dispersion obtained from checklist was found.It was found that the 52 % of the training and lifeguard choise of the pools in Turkey,64 % of the emergency action equipment,71 % of the signs and signboards for the safety of the pool,75 % of the pool edge and its surroundings are not suitable for the standards and that these threaten the swimmers health importantly.Consequently,we are in the opinion that the pool staff should receive the periodical training about the first aid and using emergency situation equipment.And it is necessary that the Ministry Responsible for sports,Ministry of Interior,Ministry of Health,Ministry of Tourism be cooperate with water sports federations and the related civil society organizationsKey Words: .

  12. Development of Pool-type Sodium-cooled Fast Reactor System Analysis Code%池式钠冷快堆系统分析程序开发

    Institute of Scientific and Technical Information of China (English)

    王晋; 张东辉; 胡文军

    2016-01-01

    针对池式钠冷快堆的特点,在对快堆系统的水力模型、热工模型和中子动力学模型进行详细分类和建模的基础上,利用 FORTRAN95语言开发了可用于池式钠冷快堆事故分析的系统分析程序(FASYS程序)。以中国实验快堆为计算对象对FASYS程序模型进行了初步验证,所获得的结果和试验值与其他系统程序计算值符合良好,证明了所开发的系统分析程序的正确性。%According to the characteristics of pool‐type sodium‐cooled fast reactor ,and with the fast reactor hydraulic model , thermal model and neutron kinetics model thoroughly classified and developed ,a fast reactor system analysis code (FASYS code) was developed by FORTRAN95 language for pool‐type sodium‐cooled fast reactor acci‐dent analysis .Transient conditions in CEFR were calculated with FASYS code and the results were used for code validation .The calculation results are consistent with the test data and other fast reactor system analysis code results , and the correctness of the FASYS code is proved .

  13. Going with the flow or swimming against the tide: should children with central venous catheters swim?

    Science.gov (United States)

    Miller, Jessica; Dalton, Meghan K; Duggan, Christopher; Lam, Shirley; Iglesias, Julie; Jaksic, Tom; Gura, Kathleen M

    2014-02-01

    Children who require long-term parenteral nutrition (PN) have central venous catheters (CVCs) in place to allow the safe and effective infusion of life-sustaining fluids and nutrition. Many consider recreational swimming to be a common part of childhood, but for some, the risk may outweigh the benefit. Children with CVCs may be at increased risk of exit site, tunnel, and catheter-related bloodstream infections (CRBSIs) if these catheters are immersed in water. The purpose of this review is to evaluate the current literature regarding the risk of infection for patients with CVCs who swim and determine if there is consensus among home PN (HPN) programs on this controversial issue. A total 45 articles were reviewed and 16 pediatric HPN programs were surveyed regarding swimming and CVCs. Due to the limited data available, a firm recommendation cannot be made. Recreational water associated outbreaks are well documented in the general public, as is the presence of human pathogens even in chlorinated swimming pools. As a medical team, practitioners can provide information and education regarding the potential risk, but ultimately the decision lies with the parents. If the parents decide swimming is worth the risk, they are encouraged to use products designed for this use and to change their child's dressing immediately after swimming. Due to our experience with a fatal event immediately after swimming, we continue to strongly discourage patients with CVCs from swimming. Further large and well-designed studies regarding the risk of swimming with a CVC are needed to make a strong, evidence-based recommendation.

  14. Effect of the starting and turning performances on the subsequent swimming parameters of elite swimmers.

    Science.gov (United States)

    Veiga, Santiago; Roig, Andreu

    2017-03-01

    In the present research, we examined the effect of the starting and turning performances on the subsequent swimming parameters by (1) comparing the starting and turning velocities with the swimming parameters on the emersion and mid-pool segments and (2) by relating the individual behaviour of swimmers during the start and turns with subsequent behaviour on each swimming lap. One hundred and twelve 100 m performances on the FINA 2013 World Swimming Championships were analysed by an image-processing system (InThePool 2.0®). At the point of the start emersion, the swimming parameters of the 100-m elite swimmers were substantially greater than the mid-pool parameters, except on the breaststroke races. On the other hand, no diminution in the swimming parameters was observed between the turn emersion and the mid-pool swimming, except on the butterfly and backstroke male races. Changes on the surface swimming kinematics were not generally related to the starting or turning parameters, although male swimmers who develop faster starts seem to achieve faster velocities at emersion. Race analysts should be aware of a transfer of momentum when swimmers emerge from underwater with implications on the subsequent swimming kinematics, especially for male swimmers who employ underwater undulatory techniques.

  15. The Pool with the Movable Bottom

    Science.gov (United States)

    American School and University, 1977

    1977-01-01

    A major diagnostic, therapeutic, educational, and training center for the handicapped has under construction a swimming pool with a floor that will rise to deck level to enable handicapped persons to roll their wheel chairs on and then float free as the floor is lowered. (Author/MLF)

  16. Vernal Pools

    Data.gov (United States)

    California Department of Resources — This is a polygon layer representing existing vernal pool complexes in California's Central Valley, as identified and mapped by Dr. Robert F. Holland. The purpose of...

  17. Swimming and the heart.

    Science.gov (United States)

    Lazar, Jason M; Khanna, Neel; Chesler, Roseann; Salciccioli, Louis

    2013-09-20

    Exercise training is accepted to be beneficial in lowering morbidity and mortality in patients with cardiac disease. Swimming is a popular recreational activity, gaining recognition as an effective option in maintaining and improving cardiovascular fitness. Swimming is a unique form of exercise, differing from land-based exercises such as running in many aspects including medium, position, breathing pattern, and the muscle groups used. Water immersion places compressive forces on the body with resulting physiologic effects. We reviewed the physiologic effects and cardiovascular responses to swimming, the cardiac adaptations to swim training, swimming as a cardiac disease risk factor modifier, and the effects of swimming in those with cardiac disease conditions such as coronary artery disease, congestive heart failure and the long-QT syndrome.

  18. Experimental investigation of heat transfer during severe accident of a Pressurized Heavy Water Reactor with simulated decay heat generation in molten pool inside calandria vessel

    Energy Technology Data Exchange (ETDEWEB)

    Prasad, Sumit Vishnu, E-mail: svprasad@barc.gov.in; Nayak, Arun Kumar, E-mail: arunths@barc.gov.in

    2016-07-15

    Highlights: • Scaled test facility simulating the calandria vessel and calandria vault water of PHWR with simulated decay heat was built. • Experiments conducted with simulant material at about 1200 °C. • Experimental result shows that melt coolability and growth rate of crust thickness are affected by presence of decay heat. • No gap was observed between the crust and vessel on opening. • Result shows that vessel integrity is intact with presence of water inside water tank in both cases. - Abstract: The present study focuses on experimental investigation in a scaled facility of an Indian PHWR to investigate the coolability of molten corium with simulated decay heat in the simulated calandria vessel. Molten borosilicate glass was used as the simulant due to its comparable heat transfer characteristics similar to prototypic material. About 60 kg of the molten material was poured into the test section at about 1200 °C. Decay heat in the melt pool was simulated using four high watt heaters cartridges, each having 9.2 kW. The temperature distributions inside the molten pool, across the vessel wall thickness and vault water were measured. Experimental results obtained are compared with the results obtained previously for no decay heat case. The results indicated that presence of decay heat seriously affects the coolability behaviour and formation of crust in the melt pool. The location and magnitude of maximum heat flux and surface temperature of the vessel also are affected in the presence of decay heat.

  19. Swimming Orientation for Preschoolers.

    Science.gov (United States)

    Smith, Mary Lou

    1990-01-01

    Techniques which are designed to dispel fears and promote confident learning are offered to preschool swimming instructors. Safety, class organization, water games, and class activities are discussed. (IAH)

  20. Creatine supplementation and swim performance: a brief review.

    Science.gov (United States)

    Hopwood, Melissa J; Graham, Kenneth; Rooney, Kieron B

    2006-03-01

    Nutritional supplements are popular among athletes participating in a wide variety of sports. Creatine is one of the most commonly used dietary supplements, as it has been shown to be beneficial in improving performance during repeated bouts of high-intensity anaerobic activity. This review examines the specific effects of creatine supplementation on swimming performance, and considers the effects of creatine supplementation on various measures of power development in this population. Research performed on the effect of creatine supplementation on swimming performance indicates that whilst creatine supplementation is ineffective in improving performance during a single sprint swim, dietary creatine supplementation may benefit repeated interval swim set performance. Considering the relationship between sprint swimming performance and measurements of power, the effect of creatine supplementation on power development in swimmers has also been examined. When measured on a swim bench ergometer, power development does show some improvement following a creatine supplementation regime. How this improvement in power output transfers to performance in the pool is uncertain. Although some evidence exists to suggest a gender effect on the performance improvements seen in swimmers following creatine supplementation, the majority of research indicates that male and female swimmers respond equally to supplementation. A major limitation to previous research is the lack of consideration given to the possible stroke dependant effect of creatine supplementation on swimming performance. The majority of the research conducted to date has involved examination of the freestyle swimming stroke only. The potential for performance improvements in the breaststroke and butterfly swimming strokes is discussed, with regards to the biomechanical differences and differences in efficiency between these strokes and freestyle. Key PointsCreatine supplementation does not improve single sprint

  1. Espacio Pool

    OpenAIRE

    2013-01-01

    Espacio Pool es un grupo abierto de usuarios vinculados a la Facultad de Bellas Artes UCM que actúa sobre los márgenes que la circundan. Toma su nombre de los estanques vacíos ubicados en los jardines de la cafetería, y elige el término anglosajón por sus connotaciones relativas a lo participativo y autogestionado. Su objetivo es habitar los espacios de “vacuidad” para que sean efectivos y permutadores. Espacio Pool organiza la celebración de encuentros a partir de la construcción de disposit...

  2. 多孔介质方法在池式快堆系统分析软件SAC-CFR三维钠池计算模型中的应用%Application of Porous Medium Method on Three-Dimensional Sodium Pool Model for Pool-Type Fast Reactor System Analysis Code SAC-CFR

    Institute of Scientific and Technical Information of China (English)

    隋丹婷; 陆道纲; 任丽霞; 刘一哲

    2012-01-01

    为准确分析池式快堆热钠池内的热工水力学特性,在已开发出的用于池式快堆系统分析的钠池三维计算模型的基础上,应用多孔介质方法建立钠池内中间热交换器、主泵、事故热交换器及屏蔽柱模型,完成了含有多孔介质模型和复杂几何边界的钠池三维计算模型开发.将该模型嵌入池式快堆系统分析软件SAC-CFR后,分析了中国实验快堆在稳态运行和紧急停堆工况下钠池内的流场分布,初步证明了所采用的多孔介质模型的合理性,为下一步非能动余热排出系统模型的开发做准备.%To simulate the fluid dynamic and thermal characteristics in sodium pool accurately , newly three-dimensional hot pool analysis model with porous medium model and complex geometry was developed after incorporating the porous model of penetration components into three-dimensional model developed already for system analysis of pool-type fast reactor. Penetration components include intermediate heat exchanger, primary pump, decay heat exchanger, and radial shielding. After coupling with the system analysis code SAC-CFR, the newly coupled code was applied to analyze the flow field in hot pool under steady-state operation condition and after scram. The agreement between the computational flow field and the geometry of hot pool shows the effectiveness of porous medium model, which makes preparations for further development of passive residual heat removal system.

  3. Safe operation and maintenance of research reactor

    Energy Technology Data Exchange (ETDEWEB)

    Munsorn, S. [Reactor Operation Division, Office of Atomic Energy for Peace, Chatuchak, Bangkok (Thailand)

    1999-10-01

    The first Thai Research Reactor (TRR-1) was established in 1961 at the Office of Atomic Energy for Peace (OAEP), Bangkok. The reactor was light water moderated and cooled, using HEU plate-type with U{sub 3}O{sub 8}- Al fuel meat and swimming pool type. The reactor went first critical on October 27, 1962 and had been licensed to operate at 1 MW (thermal). On June 30, 1975 the reactor was shutdown for modification and the core and control system was disassemble and replaced by that of TRIGA Mark III type while the pool cooling system, irradiation facilities and other were kept. Thus the name TRR-1/M1' has been designed due to this modification the fuel has been changed from HEU plate type to Uranium Zirconium Hydride (UZrH) Low Enrichment Uranium (LEU) which include 4 Fuel Follower Control Rods and 1 Air Follower Control Rod. The TRR-1/M1 went critical on November 7, 1977 and the purpose of the operation are training, isotope production and research. Nowadays the TRR-1/M1 has been operated with core loading No.12 which released power of 1,056 MWD. (as of October 1998). The TRR-1/M1 has been operated at the power of 1.2 MW, three days a week with 34 hours per week, Shut-down on Monday for weekly maintenance and Tuesday for special experiment. The everage energy released is about 40.8 MW-hour per week. Every year, the TRR-1/M1 is shut-down about 2 months between February to March for yearly maintenance. (author)

  4. The pool chlorine hypothesis and asthma among boys.

    LENUS (Irish Health Repository)

    Cotter, A

    2012-01-31

    Swimming pool sanitation has largely been concerned with the microbiological quality of pool water, which is normally treated using a number of chlorine products. Recent studies have pointed to the potential hazards of chlorine by-products to the respiratory epithelium, particularly in indoor, poorly ventilated, pools. The aim of our study was to elucidate whether chronic exposure to indoor chlorinated swimming pools was associated with an increased likelihood of the development of asthma in boys. METHODS: The subjects were boys aged between 6 and 12 years. Data was collected by means of parental responses to a standardized asthma questionnaire (ISAAC: International Study of Asthma and Allergies in Childhood), supplemented with additional questions regarding frequency of attendance, number of years attendance, whether the child is a swimming team member. The questionnaire return rate was 71\\/% (n = 121). 23 boys were excluded on the basis that they had asthma before they started swimming (n = 97). There was a significant association between number of years a boy had been swimming and the likelihood of wheezing in the last 12 months (p = 0.009; OR = 1.351; 95% CI = 1.077-1.693) and diagnosed asthma (p = 0.046; OR = 1.299; 95% CI = 1.004-1.506). The greater the number the number of years a boy had been attending an indoor, chlorinated pool, the greater the likelihood of wheezing in the last 12 months or "had asthma". Age, parental smoking habits and being a swimming team member had no association with any of the asthma variables examined. Swimming pool attendance may be a risk factor in asthma in boys.

  5. Independent Swimming for Children with Severe Physical Impairments.

    Science.gov (United States)

    Grosse, Susan J.; McGill, Christine D.

    1979-01-01

    Techniques are described for teaching severely physically disabled persons to swim. Approaches begin with a discussion of water adjustment progression and proceed through achieving breath control, mobility, developing movement in a supine position, and developing recovery. The conclusion addresses such final steps toward independence as pool entry…

  6. Technology of Anodization of Aluminum Pool Shell for Nuclear Reactor in Oxalic Acid Solution%草酸溶液中铝池壳的阳极氧化技术

    Institute of Scientific and Technical Information of China (English)

    白新德; 白光美; 郭金梁; 陈鹤鸣; 马春来; 彭德全; 董铎; 钟大辛; 陆金法; 郭宝华; 周昕

    2004-01-01

    A lot of experiments about the anodization of A0 pure aluminum in oxalic acid solution were carried out. The technology parameters were decided, including the anode current density, the oxidization time and the temperature of the electrolyte solution. During the anode oxidization of the pool shell, some special key technologies were solved, including the oxidization technology of large equipment, the technology of the treatment with layer by layer and sealing with thin plastic films, the selection of the power, the circular cooling of the electrolyte solution, etc. Treating the whole pool shell with such measures, the abilities of the corrosion-proof and protection were greatly improved. The nuclear reactor has run for 37 years (from 1964 to 2001), by now the oxidization film on the surface of the pool shell is still bright. It can confirm that treating of the whole pool shell is successful and necessary, which can provide the help and reference for building the same model nuclear reactors.%清华大学核能研究院屏蔽实验反应堆池壳用A0纯铝制成,并于1964年对池壳进行了全部阳极氧化处理.至2001年,反应堆运行了37年,池壳表面仍然有一层发亮的氧化膜,与国内外同类型的未经阳极氧化处理的反应堆相比较,说明氧化膜极好地保护了池壳.该反应堆池壳容积大于50 m3.表面积达100 m2,把这样大的铝制设备在完全安装完毕后进行全部表面阳极氧化处理,在处理工艺上是很困难的.本文阐明了解决这些问题的方法.对A0纯铝在草酸中的阳极氧化做了许多实验,获得了A0纯铝在3%(w/%)草酸中的阳极氧化的基本规律,并确定了最终的工艺参数.包括氧化电流密度,氧化时间和电解液的温度.在铝池壳的阳极氧化过程中解决了许多关键的工艺:如大型工件阳极氧化工艺、氧化机制、性能;分层处理与薄膜密封技术;电源的选择;电解液的循环冷却;氧化膜的质量检测等.

  7. Measurement of the Residual Stresses and Investigation of Their Effects on a Hardfaced Grid Plate due to Thermal Cycling in a Pool Type Sodium-Cooled Fast Reactor

    Directory of Open Access Journals (Sweden)

    S. Balaguru

    2016-01-01

    Full Text Available In sodium-cooled fast reactors (SFR, grid plate is a critical component which is made of 316 L(N SS. It is supported on core support structure. The grid plate supports the core subassemblies and maintains their verticality. Most of the components of SFR are made of 316 L(N/304 L(N SS and they are in contact with the liquid-metal sodium which acts as a coolant. The peak operating temperature in SFR is 550°C. However, the self-welding starts at 500°C. To avoid self-welding and galling, hardfacing of the grid plate has become necessary. Nickel based cobalt-free colmonoy 5 has been identified as the hardfacing material due to its lower dose rate by Plasma Transferred Arc Welding (PTAW. This paper is concerned with the measurement and investigations of the effects of the residual stress generated due to thermal cycling on a scale-down physical model of the grid plate. Finite element analysis of the hardfaced grid plate model is performed for obtaining residual stresses using elastoplastic analysis and hence the results are validated. The effects of the residual stresses due to thermal cycling on the hardfaced grid plate model are studied.

  8. Sand swimming lizard: sandfish

    CERN Document Server

    Maladen, Ryan D; Kamor, Adam; Goldman, Daniel I

    2009-01-01

    We use high-speed x-ray imaging to reveal how a small (~10cm) desert dwelling lizard, the sandfish (Scincus scincus), swims within a granular medium [1]. On the surface, the lizard uses a standard diagonal gait, but once below the surface, the organism no longer uses limbs for propulsion. Instead it propagates a large amplitude single period sinusoidal traveling wave down its body and tail to propel itself at speeds up to ~1.5 body-length/sec. Motivated by these experiments we study a numerical model of the sandfish as it swims within a validated soft sphere Molecular Dynamics granular media simulation. We use this model as a tool to understand dynamics like flow fields and forces generated as the animal swims within the granular media. [1] Maladen, R.D. and Ding, Y. and Li, C. and Goldman, D.I., Undulatory Swimming in Sand: Subsurface Locomotion of the Sandfish Lizard, Science, 325, 314, 2009

  9. Development of System Analysis Code for Pool-Type Fast Reactor Under Transient Operation%池式快堆系统瞬态分析软件开发

    Institute of Scientific and Technical Information of China (English)

    陆道纲; 隋丹婷

    2012-01-01

    为实现快堆系统分析软件国产化,在已开发的适用于稳态计算的池式快堆系统分析软件SAC-CFR的基础上,进一步开发了系统各部件的瞬态模型、控制系统和保护系统模型、瞬态工况热工水力学的求解逻辑,完成瞬态计算功能的开发.通过对日本文殊快堆45%功率汽机跳闸工况进行建模分析,验证了SAC-CFR用于系统瞬态分析的有效性,为进一步开发非能动余热排出系统分析模型打下了基础.%Aiming at developing system analysis code independently, the system analysis code for pool-type fast reactor in China (SAC-CFR) under transient operation was developed with further development of component transient model, plant control and protection system model, calculation logic for system transient thermal-hydraulic analysis based on the former SAC-CFR version applicable to steady state analysis. The transient started from turbine trip test at 45 % thermal output in the Monju Plant was analyzed with the developed SAC-CFR. A good agreement between the calculated results and the test data was obtained. SAC-CFR is now ready to incorporate passive residual heat removal model for China Experimental Fast Reactor.

  10. CREATINE SUPPLEMENTATION AND SWIM PERFORMANCE: A BRIEF REVIEW

    Directory of Open Access Journals (Sweden)

    Melissa J. Hopwood

    2006-03-01

    Full Text Available Nutritional supplements are popular among athletes participating in a wide variety of sports. Creatine is one of the most commonly used dietary supplements, as it has been shown to be beneficial in improving performance during repeated bouts of high-intensity anaerobic activity. This review examines the specific effects of creatine supplementation on swimming performance, and considers the effects of creatine supplementation on various measures of power development in this population. Research performed on the effect of creatine supplementation on swimming performance indicates that whilst creatine supplementation is ineffective in improving performance during a single sprint swim, dietary creatine supplementation may benefit repeated interval swim set performance. Considering the relationship between sprint swimming performance and measurements of power, the effect of creatine supplementation on power development in swimmers has also been examined. When measured on a swim bench ergometer, power development does show some improvement following a creatine supplementation regime. How this improvement in power output transfers to performance in the pool is uncertain. Although some evidence exists to suggest a gender effect on the performance improvements seen in swimmers following creatine supplementation, the majority of research indicates that male and female swimmers respond equally to supplementation. A major limitation to previous research is the lack of consideration given to the possible stroke dependant effect of creatine supplementation on swimming performance. The majority of the research conducted to date has involved examination of the freestyle swimming stroke only. The potential for performance improvements in the breaststroke and butterfly swimming strokes is discussed, with regards to the biomechanical differences and differences in efficiency between these strokes and freestyle

  11. Radioactivity and radioprotection: the every day life in a nuclear installation. Press tour at CEA/GRENOBLE 18 november 1999; Radioactivite et radioprotection: la vie quotidienne dans une installation nucleaire. Voyage de presse au Centre CEA/CADARACHE 18 novembre 1999

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1999-11-01

    In the framework of the public information, this paper gives a general information on the radioactivity and the radioprotection at the CEA/Cadarache center. A first part is devoted to a presentation of the radioactivity with definitions and radiation effects on the human being and the environment. An other part presents the radioprotection activities and regulations. The last part deals with specific activities of the CEA/Cadarache: the CASCAD installations for spent fuels storage, the LECA Laboratory for the Examination of Active Fuels and a dismantling installation for big irradiated objects. Historical aspects of the CEA/Cadarache are also provided. (A.L.B.)

  12. Achieving compliance with pool fencing legislation in New Zealand: how much progress has been made in 10 years?

    Science.gov (United States)

    Gulliver, Pauline; Chalmers, David; Cousins, Kimberley

    2009-09-01

    The objective of this study was to assess current levels of enforcement and compliance with the Fencing of Swimming Pools Act 1987, and to determine if enforcement activity and compliance has changed since 1997. A postal questionnaire was sent to all of 73 territorial authorities in New Zealand. Main outcome measures include number and rates of swimming pools (per 1000 dwellings and per 1000 population); mean number of building consents and code compliance certificates issued for pools per territorial authority; mean number of pool inspections made per territorial authority; and the proportion of pools complying with the requirements of the Act. There was around a 9% increase in the prevalence of domestic swimming pools in New Zealand, from 46 pools/1000 dwellings in 1997 to 50 pools/1000 dwellings in 2006 was observed. There has been a 65% increase in the proportion of pools reported as complying with the Act. The proportion of authorities reporting a programme of re-inspection for domestic swimming pools increased from 28% in 1997 to 63% in 2006. There has also been an increase in the proportion of domestic swimming pools recorded as complying with the Act. Finally, a considerable improvement in the enforcement and monitoring activities of territorial authorities in New Zealand was found.

  13. Calculating the accumulative neutron fluence rate of Al alloy on upper link chest of Swimming Pool Research Reactor-300%300#研究堆寿期内上联箱铝材中子注量分析

    Institute of Scientific and Technical Information of China (English)

    冯琦杰; 刘耀光; 杨万奎; 张松宝; 石炳元; 杨锐

    2015-01-01

    材料在辐照过程中所受的中子注量是辐照性能研究中的一个重要参数.上联箱铝材作为300#研究堆关键结构材料,经历了从反应堆首次临界到退役的全过程,极具材料辐照效应研究价值.为获取整个反应堆运行寿期内的上联箱中子注量水平,须克服堆芯装载变化频繁与堆芯不断扩大装载两大关键难点,故提出了堆芯归并等效计算方法.通过该方法的成功应用,得到了300#研究堆寿期内上联箱铝材的中子注量,并进行了误差分析.

  14. Fast neutron spectrum in the reflector of swimming pool reactor behind metallics slabs; Spectre des neutrons rapides dans le reflecteur d'une pile a eau legere derriere des ecrans metalliques

    Energy Technology Data Exchange (ETDEWEB)

    Brousse, J.C. [Commissariat a l' Energie Atomique, Grenoble (France). Centre d' Etudes Nucleaires

    1970-07-01

    The large perturbations of fast neutron spectrum were measured behind lead, aluminium and iron slabs in the Siloette reflector at the CENG. The neutron slowing down is chiefly depending of the inelastic reaction. The reaction cross section increases with energy; a spectrum softening is deduced. This is verified. We tried to determine the spectrum shape by calculation to fit the measurements. Calculations were firstly made in unidimensional geometry by the NIOBE transport equation resolution code and by the SANE Monte-Carlo code. The results does not agree with the experimental determined values. Finally a semi-empirical method for studying a tridimensional geometry was chosen. We have obtained calculation results in a perfect agreement with measurements. The method is described. (author) [French] Les experiences realisees dans le reflecteur de la pile a eau legere SILOETTE du CENG avec des ecrans de plomb, d'aluminium et de fer, nous ont permis de caracteriser les deformations importantes du spectre des neutrons rapides par ces materiaux. Nous avons verifie que la loi de ralentissement preponderante est la reaction de diffusion inelastique dont la section efficace croit avec l'energie, ce qui entraine un amollissement du spectre. Nous avons cherche a determiner par le calcul la trace des spectres de neutrons rapides correspondant aux points de mesure. Les premiers calculs effectues en geometrie unidimensionnelle a l'aide d'un code de resolution de l'equation du transport (NIOBE) et d'un code de Monte-Carlo (SANE) nous ont donne des resultats imparfaits. On a alors choisi une methode de calcul approche capable d'etudier une geometrie tridimensionnelle. Cette methode nous a donne des resultats de calcul qui s'approchaient a quelques pour cent des resultats experimentaux. La methode est decrite. (auteur)

  15. Healthy Swimming/Recreational Water

    Science.gov (United States)

    ... Now Available! Q&A with Missy Franklin: Olympic Gold Medalist and Healthy Swimming Champion New Report on ... enter your email address: Enter Email Address Submit Button What's this? Healthy Swimming Swimmers Health Benefits of ...

  16. Bioinspired swimming simulations

    Science.gov (United States)

    Bergmann, Michel; Iollo, Angelo

    2016-10-01

    We present a method to simulate the flow past bioinspired swimmers starting from pictures of an actual fish. The overall approach requires i) a skeleton graph generation to get a level-set function from pictures; ii) optimal transportation to obtain the velocity on the body surface; iii) flow simulations realized with a Cartesian method based on penalization. This technique can be used to automate modeling swimming motion from data collected by biologists. We illustrate this paradigm by simulating the swimming of a mackerel fish.

  17. Simulations of optimized anguilliform swimming.

    Science.gov (United States)

    Kern, Stefan; Koumoutsakos, Petros

    2006-12-01

    The hydrodynamics of anguilliform swimming motions was investigated using three-dimensional simulations of the fluid flow past a self-propelled body. The motion of the body is not specified a priori, but is instead obtained through an evolutionary algorithm used to optimize the swimming efficiency and the burst swimming speed. The results of the present simulations support the hypothesis that anguilliform swimmers modify their kinematics according to different objectives and provide a quantitative analysis of the swimming motion and the forces experienced by the body. The kinematics of burst swimming is characterized by the large amplitude of the tail undulations while the anterior part of the body remains straight. In contrast, during efficient swimming behavior significant lateral undulation occurs along the entire length of the body. In turn, during burst swimming, the majority of the thrust is generated at the tail, whereas in the efficient swimming mode, in addition to the tail, the middle of the body contributes significantly to the thrust. The burst swimming velocity is 42% higher and the propulsive efficiency is 15% lower than the respective values during efficient swimming. The wake, for both swimming modes, consists largely of a double row of vortex rings with an axis aligned with the swimming direction. The vortex rings are responsible for producing lateral jets of fluid, which has been documented in prior experimental studies. We note that the primary wake vortices are qualitatively similar in both swimming modes except that the wake vortex rings are stronger and relatively more elongated in the fast swimming mode. The present results provide quantitative information of three-dimensional fluid-body interactions that may complement related experimental studies. In addition they enable a detailed quantitative analysis, which may be difficult to obtain experimentally, of the different swimming modes linking the kinematics of the motion with the forces

  18. Keila Tervisekeskus. Ujula = Keila Health Club. Swimming Pool / Ain Padrik

    Index Scriptorium Estoniae

    Padrik, Ain, 1947-

    2001-01-01

    Projekteerija: Arhitektuuribüroo Künnapu & Padrik. Arhitektid Ain Padrik ja Kristi Alamaa, sisearhitekt Sirje Männik. Konstruktsioonid: Jaan Laks, A-Grupp. Ujulas on võistlus- ja lastebassein, suvel on avatud välibassein. 5 ill.: I korruse plaan, ristlõige, vaated

  19. Infections Unlikely to be Spread Through Swimming Pools

    Science.gov (United States)

    ... lice, MRSA (methicillin-resistant Staphylococcus aureus ), and pin worm are unlikely to be spread through the use ... boils) that may be: Mistaken for spider bites Red, swollen, painful, warm to the touch, and have ...

  20. Multi purpose research reactor

    Energy Technology Data Exchange (ETDEWEB)

    Raina, V.K. [Research Reactor Design and Projects Division, Bhabha Atomic Research Centre, Mumbai 400085 (India)]. E-mail: vkrain@magnum.barc.ernet.in; Sasidharan, K. [Research Reactor Design and Projects Division, Bhabha Atomic Research Centre, Mumbai 400085 (India); Sengupta, Samiran [Research Reactor Design and Projects Division, Bhabha Atomic Research Centre, Mumbai 400085 (India); Singh, Tej [Research Reactor Services Division, Bhabha Atomic Research Centre, Mumbai 400085 (India)

    2006-04-15

    At present Dhruva and Cirus reactors provide the majority of research reactor based facilities to cater to the various needs of a vast pool of researchers in the field of material sciences, physics, chemistry, bio sciences, research and development work for nuclear power plants and production of radio isotopes. With a view to further consolidate and expand the scope of research and development in nuclear and allied sciences, a new 20 MWt multi purpose research reactor is being designed. This paper describes some of the design features and safety aspects of this reactor.

  1. Investigación de un brote respiratorio agudo por exposición a cloro gas en una piscina pública Investigation of an outbreak of acute respiratory illness due to exposure to chlorine gas in a public swimming pool

    Directory of Open Access Journals (Sweden)

    Diego Almagro Nievas

    2008-06-01

    Full Text Available Se diseñó un estudio de casos y controles para investigar el accidente químico ocurrido en una piscina pública en el verano de 2005 y describir los factores ambientales responsables, analizar el efecto del cloro gas y valorar la evolución clínica y funcional del aparato respiratorio. Las intervenciones fueron las siguientes: inspecciones ambientales, encuesta epidemiológica (variables sociodemográficas, ubicación en el momento del accidente, olor percibido y seguimiento clínico y espirométrico de la función respiratoria. Se encuestaron 65 casos y 48 controles. El suceso se produjo al mezclar accidentalmente ácido clorhídrico e hipoclorito sódico, lo que generó cloro gas. Los síntomas predominantes fueron tos y disnea. El riesgo de enfermar en niños era 10 veces mayor si tenían una enfermedad respiratoria previa y 4 veces superior si estaban a una distancia inferior a 40 m del lugar del accidente. Todos los casos evolucionaron hacia la curación, excepto uno que tenía antecedentes asmáticos.A case-control study was designed to investigate a chemical accident that occurred in a swimming-pool in the summer of 2005. The aim was to describe the environmental factors involved in the accident, to assess the effect of chlorine gas on the respiratory system, and to perform a clinical and spirometric follow-up. The following interventions were carried out: environmental inspection, epidemiologic survey (including sociodemographic variables, location at the time of the accident, perception of an abnormal smell, and clinical and spirometric outcomes to assess respiratory function. Sixty-five cases and 48 controls were identified and interviewed. The accident was produced by accidental admixture of hydrochloric acid with sodium hypochlorite resulting in chlorine gas release. The main clinical symptoms were dyspnea and cough. The risk of becoming ill was 10-fold higher in children with a previous lung disease and was 4-fold higher when

  2. Analysis by the Monte Carlo method of doses around the pool of storage of the control rods irradiated in a BWR reactor; Analisis mediante el metodo de Monte Carlo de las dosis alrededor de la piscina de almacenamiento de las barras de control irradiadas en un reactror BWR

    Energy Technology Data Exchange (ETDEWEB)

    Rodenas, J.; Gallardo, S.

    2011-07-01

    The control rods of a boiling water reactor (BWR) are subject to a neutron flux and thus become activated during their stay in the reactor core. Activation occurs especially in the stainless steel components and impurities. The activity generated results in a dose around the bar, while it le unimportant in the reactor, but to be taken into account when removed f ron it. The bars drawn are stored on hangers placed in the storage pools of spent fuel f ron the plant. Each hanger 12 accommodates control rods and are arranged so that at least three meters of water abode the heads of the control rods. The dose received by potentially exposed workers who are in the vicinity of the storage must be calculated to ensure adequate protection of the came. This dose can be decreased significantly by changing the arrangement of the bars on hangers.

  3. Hawaii ESI: POOLS (Anchialine Pool Points)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This data set contains sensitive biological resource data for anchialine pools in Hawaii. Anchialine pools are small, relatively shallow coastal ponds that occur...

  4. LMFBR type reactor

    Energy Technology Data Exchange (ETDEWEB)

    Kawakami, Hiroto

    1995-02-07

    A reactor container of the present invention has a structure that the reactor container is entirely at the same temperature as that at the inlet of the reactor and, a hot pool is incorporated therein, and the reactor container has is entirely at the same temperature and has substantially uniform temperature follow-up property transiently. Namely, if the temperature at the inlet of the reactor core changes, the temperature of the entire reactor container changes following this change, but no great temperature gradient is caused in the axial direction and no great heat stresses due to axial temperature distribution is caused. Occurrence of thermal stresses caused by the axial temperature distribution can be suppressed to improve the reliability of the reactor container. In addition, since the laying of the reactor inlet pipelines over the inside of the reactor is eliminated, the reactor container is made compact and the heat shielding structures above the reactor and a protection structure of container walls are simplified. Further, secondary coolants are filled to the outside of the reactor container to simplify the shieldings. The combined effects described above can improve economical property and reliability. (N.H.).

  5. Status and some safety philosophies of the China advanced research reactor CARR

    Energy Technology Data Exchange (ETDEWEB)

    Luzheng Yuan [China Inst. of Atomic Energy, Beijing, BJ (China). Reactor Engineering Research and Design Dept.

    2001-07-01

    The existing two research reactors, HWRR (heavy water research reactor) and SPR (swimming pool reactor), have been operated by China Institute of Atomic Energy (CIAE) since, respectively, 1958 and 1964, and are both in extending service and facing the aging problem. It is expected that they will be out of service successively in the beginning decade of the 21{sup st} century. A new, high performance and multipurpose research reactor called China advanced research reactor (CARR) will replace these two reactors. This new reactor adopts the concept of inverse neutron trap compact core structure with light water as coolant and heavy water as the outer reflector. Its design goal is as follows: under the nuclear power of 60MW, the maximum unperturbed thermal neutron flux in peripheral D{sub 2}O reflector not less than 8 x 10{sup 14} n/cm{sup 2}. s while in central experimental channel, if the central cell to be replaced by an experimental channel, the corresponding value not less than 1 x 10{sup 15} n/cm{sup 2}. s. The main applications for this research reactor will cover RI production, neutron scattering experiments, NAA and its applications, neutron photography, NTD for monocrystaline silicon and applications on reactor engineering technology. By the end of 1999, the preliminary design of CARR was completed, then the draft of preliminary safety analysis report (PSAR) was submitted to the relevant authority at the end of 2000 for being reviewed. Now, the CARR project has entered the detail design phase and safety reviewing procedure for obtaining the construction permit from the relevant licensing authority. This paper will only briefly introduce some aspects of safety philosophy of CARR design and PSAR. (orig.)

  6. Pool Rules: A Survival Guide for Parents and Children

    Science.gov (United States)

    Grosse, Susan J.

    2008-01-01

    In most sports and physical activities rules are present to facilitate participation, outlining courtesy during play as well as establishing guidelines for keeping any competition fair. In contrast, rules for appropriate behavior in swimming pools serve a much more important purpose--that of ensuring health and safety for all participants.…

  7. The evolution of doses in the IEA-R1 reactor environment and tendencies based on the current results; Evolucao das doses no ambiente do Reator IEA-R1 e tendencias com base nos resultados atuais

    Energy Technology Data Exchange (ETDEWEB)

    Toyoda, Eduardo Yoshio

    2016-11-01

    The IPEN / CNEN-SP have a Nuclear Research Reactor-NRR named IEA-R1, in operation from 1957. It is an open swimming pool reactor using light water as shielding, moderator and as cooling, the volume of this pool is 273m{sup 3}.Until 1995 the reactor operated daily at a power of 2,0 MW. From June of that year, after a few safety modifications the reactor began operating in continuous way from Monday to Wednesday without shutdown totalizing 64 hours per week and the power was increased to 4,5MW also. Because of these changes, continuous operation and increased power, workers' doses would tend to increase. In the past several studies were conducted seeking ways to reduce the workers' doses. A study was made on the possibility to introduce a shielding at the top of the reactor core with a hot water layer. Studies have shown that a major limitation for operating a reactor at high power comes from the gamma radiation emitted by the sodium-24. Other elements such as magnesium-27, aluminum-28, Argon-51, contribute considerably to the water activity of the pool. The introduction of a hot water layer on the swimming pool would form a layer of surface, stable and free of radioactive elements with a 1.5m to 2m thickness creates a shielding to radiation from radioactive elements dissolved in water. Optimization studies proved that the installation of the hot layer was not necessary for the regime and the current power reactor operation, because other procedures adopted were more effective. From this decision the Radiological Protection Reactor Team, set up a dose assessment program to ensure them remained in low values based on principles established in national and international standards. The purpose of this paper is to analyze the individual doses of OEI (Occupationally Exposed Individual), which will be checked increasing doses resulting from recent changes in reactor operation regime and suggested viable safety and protection options, in the first instance to

  8. Calculation to experiment comparison of SPND signals in various nuclear reactor environments

    Energy Technology Data Exchange (ETDEWEB)

    Barbot, Loic; Radulovic, Vladimir; Fourmentel, Damien [CEA, DEN, DER, Instrumentation, Sensors and Dosimetry Laboratory, Cadarache, F-13108 St-Paul-Lez-Durance, (France); Snoj, Luka [Jozef Stefan Institute, Jamova cesta 39, SI-1000 Ljubljana, (Slovenia); Tarchalski, Mikolaj [National Centre for Nuclear Research, ulica Andrzeja Soltana 7, 05-400 Otwock (Swierk), (Poland); Dewynter-Marty, Veronique [CEA, DEN, DANS, DRSN, SIREN, LESCI, Saclay, F-91191 Gif sur Yvette, (France); Malouch, Fadhel [CEA, DEN, DANS, DM2S, SERMA, Saclay, F-91191 Gif sur Yvette, (France)

    2015-07-01

    In the perspective of irradiation experiments in the future Jules Horowitz Reactor (JHR), the Instrumentation Sensors and Dosimetry Laboratory of CEA Cadarache (France) is developing a numerical tool for SPND design, simulation and operation. In the frame of the SPND numerical tool qualification, dedicated experiments have been performed both in the Slovenian TRIGA Mark II reactor (JSI) and very recently in the French CEA Saclay OSIRIS reactor, as well as a test of two detectors in the core of the Polish MARIA reactor (NCBJ). A full description of experimental set-ups and neutron-gamma calculations schemes are provided in the first part of the paper. Calculation to experiment comparison of the various SPNDs in the different reactors is thoroughly described and discussed in the second part. Presented comparisons show promising final results. (authors)

  9. Nuclear Reactors

    Energy Technology Data Exchange (ETDEWEB)

    Hogerton, John

    1964-01-01

    This pamphlet describes how reactors work; discusses reactor design; describes research, teaching, and materials testing reactors; production reactors; reactors for electric power generation; reactors for supply heat; reactors for propulsion; reactors for space; reactor safety; and reactors of tomorrow. The appendix discusses characteristics of U.S. civilian power reactor concepts and lists some of the U.S. reactor power projects, with location, type, capacity, owner, and startup date.

  10. Determination of the exposition rapidity in the level 49.90 of the reactor building for the decrease in the water level of the spent fuel pool; Determinacion de la rapidez de exposion en el nivel 49.90 del edificio del reactor por la disminucion en el nivel de agua de la alberca de combustible gastado

    Energy Technology Data Exchange (ETDEWEB)

    Mijangos D, Z. E.; Herrera H, S. F.; Cruz G, M. A.; Amador C, C., E-mail: zoedelfin@gmail.com [Comision Federal de Electricidad, Central Nucleoelectrica Laguna Verde, Subgerencia de Ingenieria, Km 44.5 Carretera Cardel-Nautla, 91476 Laguna Verde, Alto Lucero, Veracruz (Mexico)

    2014-10-15

    The fuel assemblies storage in the nuclear power plant of Laguna Verde (NPP-L V) represents a crucial aspect, due to the generated dose by the decay heat of the present radio-nuclides in the assemblies retired of the reactor core, after their useful life. These spent assemblies are located inside the spent fuel pool (SFP), in the level 49.90 m in the Reload Floor of the Reactor building of NPP-L V. This leads to the protection at personnel applying the ALARA (As Low As Reasonably Achievable) criteria, fulfilling the established dose criteria by the Regulator Body the Comision Nacional de Seguridad Nuclear y Salvaguardias (CNSNS). Considering the loss scenario of the cooling system of the SFP, in which the SFP water vaporizes, is important to know the water level in which the limit of effective dose equivalent is fulfilled for the personnel. Also, is important for the instrumentation of the SFP, for the useful life of the same instruments. In this work is obtained the exposition rapidity corresponding to different water levels of SFP in the Reload Floor of NPP-L V, to identify the minimum level of water where the limit of effective dose equivalent is fulfilled of 25 rem s to the personnel, established in the Article 48 of the General Regulation of Radiological Safety of CNSNS and the Chapter 50 Section 67 of the 10-Cfr of Nuclear Regulatory Commission in USA. The water level is also identified where the exposition rapidity is of 15 m R/hr, being the value of the set point of the area radiation monitor D21-Re-N003-1, located to 125 cm over the level 49.90 meters of the Reload Floor of NPP-L V. (Author)

  11. Stirring by swimming bodies

    Energy Technology Data Exchange (ETDEWEB)

    Thiffeault, Jean-Luc, E-mail: jeanluc@math.wisc.ed [Department of Mathematics, University of Wisconsin - Madison, 480 Lincoln Dr., Madison, WI 53706 (United States); Institute for Mathematics and Applications, University of Minnesota - Twin Cities, 207 Church Street S.E., Minneapolis, MN 55455 (United States); Childress, Stephen [Courant Institute of Mathematical Sciences, New York University, 251 Mercer Street, New York, NY 10012 (United States)

    2010-07-26

    We consider the stirring of an inviscid fluid caused by the locomotion of bodies through it. The swimmers are approximated by non-interacting cylinders or spheres moving steadily along straight lines. We find the displacement of fluid particles caused by the nearby passage of a swimmer as a function of an impact parameter. We use this to compute the effective diffusion coefficient from the random walk of a fluid particle under the influence of a distribution of swimming bodies. We compare with the results of simulations. For typical sizes, densities and swimming velocities of schools of krill, the effective diffusivity in this model is five times the thermal diffusivity. However, we estimate that viscosity increases this value by two orders of magnitude.

  12. Mixing by Swimming Algae

    CERN Document Server

    Guasto, Jeffrey S; Gollub, J P; Pesci, Adriana I; Goldstein, Raymond E

    2009-01-01

    In this fluid dynamics video, we demonstrate the microscale mixing enhancement of passive tracer particles in suspensions of swimming microalgae, Chlamydomonas reinhardtii. These biflagellated, single-celled eukaryotes (10 micron diameter) swim with a "breaststroke" pulling motion of their flagella at speeds of about 100 microns/s and exhibit heterogeneous trajectory shapes. Fluorescent tracer particles (2 micron diameter) allowed us to quantify the enhanced mixing caused by the swimmers, which is relevant to suspension feeding and biogenic mixing. Without swimmers present, tracer particles diffuse slowly due solely to Brownian motion. As the swimmer concentration is increased, the probability density functions (PDFs) of tracer displacements develop strong exponential tails, and the Gaussian core broadens. High-speed imaging (500 Hz) of tracer-swimmer interactions demonstrates the importance of flagellar beating in creating oscillatory flows that exceed Brownian motion out to about 5 cell radii from the swimm...

  13. Going for a Swim

    Science.gov (United States)

    Covington, Savannah

    2016-01-01

    Is anything more refreshing than going for a nice, long swim? The math scenarios presented in this article will take the reader back to hot summer days and remind the reader what a cool dip in the water feels like. Solving these problems is enjoyable and encourages the solver to think of the many ways that math is all around--even in the middle of…

  14. Woman Swims Atlantic

    Institute of Scientific and Technical Information of China (English)

    贾庆文

    2009-01-01

    Jennifer Figge pressed her toes into the Caribbean sand, excited and exhausted as she touched land this week for the first time in almost a month. Reaching a beach in Trinidad, she became the first woman on record to s,Mm across the Atlantic Ocean-a dream she'd had since the early 1960s, when a stormy trans-Atlantic flight got her thinking she could wear a life vest and swim the rest of the way if needed.

  15. Determination of the solids retainment effectiveness of disposable swim diapers.

    Science.gov (United States)

    Maas, Richard P; Patch, Steven C; Berkowitz, Jacob F; Johnson, Holly D

    2004-06-01

    In light of recent and increasing incidences of pathogenic E. coli outbreaks at public bathing facilities attributable to non-toilet-trained infants and toddlers, many such facilities are restricting water contact for this age group. A number of manufacturers are now offering disposable "swim diapers," which claim to effectively retain fecal material under typical pool play conditions. The study reported here examined the solids retention effectiveness of three major brands of swim diapers as well as of conventional disposable diapers, under simulated water play conditions. Swim diapers of all three brands exhibited an approximately equal fine-solids retention capability of about 98 to 99 percent over 30 minutes of water immersion activity. Conventional disposable diapers invariably fell down or came apart during the experiments, resulting in very limited solids retention. This study indicates that commercially available swim diapers represent a vast improvement in reducing the potential for fecal material release in public pool facilities, but that some release will still generally occur with these products.

  16. Radio-transmitted electromyogram signals as indicators of swimming speed in lake trout and brown trout

    DEFF Research Database (Denmark)

    Thorstad, E.B.; Økland, F.; Koed, Anders

    2000-01-01

    Swimming speed and average electromyogram (EMG) pulse intervals were highly correlated in individual lake trout Salvelinus namaycush (r(2)=0.52-0.89) and brown trout Salmo trutta (r(2)=0.45-0.96). High correlations were found also for pooled data in both lake trout (r(2)=0.90) and brown trout...... of the Ema stock (r(2)=0.96) and Laerdal stock (r(2)=0.96). The linear relationship between swimming speed and average EMG pulse intervals differed significantly among lake trout and the brown trout stocks. This successful calibration of EMGs to swimming speed opens the possibility of recording swimming...... speed of free swimming lake trout and brown trout in situ. EMGs can also be calibrated to oxygen consumption to record energy expenditure. (C) 2000 The Fisheries Society of the British Isles...

  17. The launching of the construction of the Jules Horowitz Reactor; Lancement de la construction du reacteur de recherche Jules Horowitz

    Energy Technology Data Exchange (ETDEWEB)

    Anon

    2007-03-15

    In March 2007 the French deputy minister of industry has officially launched the construction of the new research reactor called Jules Horowitz (RJH) on the Cea site of Cadarache. RJH, that is due to operate in 2014, will be used to study the aging process of irradiated materials in any type of reactors, the behaviour of new nuclear fuels irradiated in different configurations and scenarios, and to produce radionuclides for nuclear medicine and high-quality doped silicon for the electronics industry. The investment that reaches 500 million euros is dispatched between Cea (50%), EDF (20%), Areva (10%) and foreign contributors (20%). (A.C.)

  18. Influence of mobile games on the process of teaching of students that can not swim

    Directory of Open Access Journals (Sweden)

    Strelnykov G.L.

    2012-02-01

    Full Text Available Considered direction in teaching of students to swimming in terms 25 meter pool. 30 students took part in an experiment. The place of mobile games in the process of teaching of novices is certain. Information of results of testing of level of physical preparedness of students is presented. Positive influence of mobile games on the process of mastering of skills of swimming and co-operations on water is marked. Forms and methods of mastering of skills and conduct in water are offered. The motive mode and forms of organization of educational process of not able to swim students is recommended.

  19. Modeling evaporation from spent nuclear fuel storage pools: A diffusion approach

    Science.gov (United States)

    Hugo, Bruce Robert

    Accurate prediction of evaporative losses from light water reactor nuclear power plant (NPP) spent fuel storage pools (SFPs) is important for activities ranging from sizing of water makeup systems during NPP design to predicting the time available to supply emergency makeup water following severe accidents. Existing correlations for predicting evaporation from water surfaces are only optimized for conditions typical of swimming pools. This new approach modeling evaporation as a diffusion process has yielded an evaporation rate model that provided a better fit of published high temperature evaporation data and measurements from two SFPs than other published evaporation correlations. Insights from treating evaporation as a diffusion process include correcting for the effects of air flow and solutes on evaporation rate. An accurate modeling of the effects of air flow on evaporation rate is required to explain the observed temperature data from the Fukushima Daiichi Unit 4 SFP during the 2011 loss of cooling event; the diffusion model of evaporation provides a significantly better fit to this data than existing evaporation models.

  20. Examining self-training procedures in leisure swimming.

    Science.gov (United States)

    J Potdevin, Francois; Normani, Clement; Pelayo, Patrick

    2013-01-01

    general health benefits whereas people aged from 20 to 30 appears to be concerned about a global health benefits and a body shape effects.Excepted middle age people, recreational swimmers have low control quality of their session even if they have a good skill level. This suggests to improve health strategy education and swimming pool environment.

  1. Microbiological Analysis in Three Diverse Natural Geothermal Bathing Pools in Iceland

    OpenAIRE

    Thorolfsdottir, Berglind Osk Th.; Marteinsson, Viggo Thor

    2013-01-01

    Natural thermal bathing pools contain geothermal water that is very popular to bathe in but the water is not sterilized, irradiated or treated in any way. Increasing tourism in Iceland will lead to increasing numbers of bath guests, which can in turn affect the microbial flora in the pools and therefore user safety. Today, there is no legislation that applies to natural geothermal pools in Iceland, as the water is not used for consumption and the pools are not defined as public swimming pools...

  2. Creatine supplementation and swimming performance.

    Science.gov (United States)

    Leenders, N M; Lamb, D R; Nelson, T E

    1999-09-01

    The purpose of this study was to determine if oral creatine (CR) ingestion, compared to a placebo (PL), would enable swimmers to maintain a higher swimming velocity across repeated interval sets over 2 weeks of supplementation. Fourteen female and 18 male university swimmers consumed a PL during a 2-week baseline period. Using a randomized, double-blind design, during the next 2 weeks subjects consumed either CR or PL. Swimming velocity was assessed twice weekly during 6 X 50-m swims and once weekly during 10 X 25-yd swims. There was no effect of CR on the 10 X 25-yd interval sets for men and women and no effect on the 6 X 50-m interval sets for women. In contrast, for men, CR significantly improved mean overall swimming velocity in the 6 X 50-m interval after 2 weeks of supplementation, whereas PL had no effect. Although ineffective in women, CR supplementation apparently enables men to maintain a faster mean overall swimming velocity during repeated swims each lasting about 30 s; however, CR was not effective for men in repeated swims each lasting about 10 - 15 s.

  3. Nutrition considerations for open-water swimming.

    Science.gov (United States)

    Shaw, Gregory; Koivisto, Anu; Gerrard, David; Burke, Louise M

    2014-08-01

    Open-water swimming (OWS) is a rapidly developing discipline. Events of 5-25 km are featured at FINA World Championships, and the international circuit includes races of 5-88 km. The Olympic OWS event, introduced in 2008, is contested over 10 km. Differing venues present changing environmental conditions, including water and ambient temperatures, humidity, solar radiation, and unpredictable tides. Furthermore, the duration of most OWS events (1-6 hr) creates unique physiological challenges to thermoregulation, hydration status, and muscle fuel stores. Current nutrition recommendations for open-water training and competition are either an extension of recommendations from pool swimming or are extrapolated from other athletic populations with similar physiological requirements. Competition nutrition should focus on optimizing prerace hydration and glycogen stores. Although swimmers should rely on self-supplied fuel and fluid sources for shorter events, for races of 10 km or greater, fluid and fuel replacement can occur from feeding pontoons when tactically appropriate. Over the longer races, feeding pontoons should be used to achieve desirable targets of up to 90 g/ hr of carbohydrates from multitransportable sources. Exposure to variable water and ambient temperatures will play a significant role in determining race nutrition strategies. For example, in extreme environments, thermoregulation may be assisted by manipulating the temperature of the ingested fluids. Swimmers are encouraged to work with nutrition experts to develop effective and efficient strategies that enhance performance through appropriate in-competition nutrition.

  4. Design and construction of an irradiation apparatus with controlled atmosphere and temperature for radiation damage evaluation of nuclear materials in the IEA-R1 research reactor

    Energy Technology Data Exchange (ETDEWEB)

    Lucki, Georgi; Silva, Jose Eduardo Rosa da; Castanheira, Myrthes; Terremoto, Luis Antonio Albiac; Teodoro, Celso Antonio; Silva, Antonio Teixeira e; Damy, Margaret de Almeida [Instituto de Pesquisas Energeticas e Nucleares (IPEN), Sao Paulo, SP (Brazil)]. E-mail: glucki@ipen.br

    2005-07-01

    A material irradiation apparatus CIMAT (Capsula de Irradiacao de Materiais) with controlled temperature and atmosphere is described. The device was specifically designed to perform experiments inside the core of the IEA-R1 swimming pool reactor and allows fast neutron (E=1 MeV) irradiations of multiple miniature metallic samples at temperature between 100 deg C and 500 deg C, in Argon or Helium atmosphere to inhibit corrosion. The aim of CIMAT is to make a comparative assessment of Radiation Embrittlement (RE) on the AS 508 cl.3 steel, of different origins (ELETROMETAL-Brazil and VITCOVICE-Chekia) used in Pressure Vessels (PV) of PWR, for fluence of 10 exp 19 nvt at 300 C, by means of mechanical post irradiation evaluation. Previous characterization of non-irradiated samples of these materials is presented. In situ electrical and magnetic measurements, at high temperatures, are foreseen to be made with this apparatus. Extensive temperature stability and leak-tightness tests performed in the reactor swimming pool have proven the CIMAT to be intrinsically safe and operational. (author)

  5. Neutron flux parameters for k{sub 0}-NAA method at the Malaysian nuclear agency research reactor after core reconfiguration

    Energy Technology Data Exchange (ETDEWEB)

    Yavar, A.R. [School of Applied Physics, Faculty of Science and Technology, University Kebangsaan Malaysia (UKM), Bangi, Selangor 43600 (Malaysia); Sarmani, S. [School of Chemical Sciences and Food Technology, Faculty of Science and Technology, University Kebangsaan Malaysia (UKM), Bangi, Selangor 43600 (Malaysia); Wood, A.K. [Analytical Chemistry Application Group, Industrial Technology Division, Malaysian Nuclear Agency (MNA), Bangi, Kajang, Selangor 43000 (Malaysia); Fadzil, S.M. [School of Applied Physics, Faculty of Science and Technology, University Kebangsaan Malaysia (UKM), Bangi, Selangor 43600 (Malaysia); Masood, Z. [Analytical Chemistry Application Group, Industrial Technology Division, Malaysian Nuclear Agency (MNA), Bangi, Kajang, Selangor 43000 (Malaysia); Khoo, K.S., E-mail: khoo@ukm.m [School of Applied Physics, Faculty of Science and Technology, University Kebangsaan Malaysia (UKM), Bangi, Selangor 43600 (Malaysia)

    2011-02-15

    The Malaysian Nuclear Agency (MNA) research reactor, commissioned in 1982, is a TRIGA Mark II swimming pool type reactor. When the core configuration changed in June 2009, it became essential to re-determine such neutron flux parameters as thermal to epithermal neutron flux ratio (f), epithermal neutron flux shape factor ({alpha}), thermal neutron flux ({phi}{sub th}) and epithermal neutron flux ({phi}{sub epi}) in the irradiation positions of MNA research reactor in order to guarantee accuracy in the application of k{sub 0}-neutron activation analysis (k{sub 0}-NAA).The f and {alpha} were determined using the bare bi-isotopic monitor and bare triple monitor methods, respectively; Au and Zr monitors were utilized in present study. The results for four irradiation positions are presented and discussed in the present work. The calculated values of f and {alpha} ranged from 33.49 to 47.33 and -0.07 to -0.14, respectively. The {phi}{sub th} and the {phi}{sub epi} were measured as 2.03 x 10{sup 12} (cm{sup -2} s{sup -1}) and 6.05 x 10{sup 10} (cm{sup -2} s{sup -1}) respectively. These results were compared to those of previous studies at this reactor as well as to those of reactors in other countries. The results indicate a good conformity with other findings.

  6. The Effects of Swimming Goggles on Swimming Performances

    OpenAIRE

    "荒井, 康夫; "アライ, ヤスオ"; YASUO", "ARAI

    1982-01-01

    "Children in swimming tend to have some fear on water due to the factors such as obstruction of breathing, blocking of vision, and changes in body equilibrium affected by buoyance. It is said that about a 5-month period is needed in order to overcome the fear in kindergarten kids during swimming instruction. The purpose of the present study was to investigate the effect of swimming goggles as a teaching aid in order to avoid the fear due to blocking vision. Ten children, 4 boys and 6 girls, i...

  7. The science of pooling

    Energy Technology Data Exchange (ETDEWEB)

    Gilbert, E.

    1995-10-01

    The pooling of data from radon studies is described. Pooling refers to the analysis of original data from several studies, not meta-analysis in which summary measures from published data are analyzed. A main objective for pooling is to reduce uncertainty and to obtain more precise estimates of risk than would be available from any single study.

  8. Pool scrubbing models for iodine components

    Energy Technology Data Exchange (ETDEWEB)

    Fischer, K. [Battelle Ingenieurtechnik GmbH, Eschborn (Germany)

    1996-12-01

    Pool scrubbing is an important mechanism to retain radioactive fission products from being carried into the containment atmosphere or into the secondary piping system. A number of models and computer codes has been developed to predict the retention of aerosols and fission product vapours that are released from the core and injected into water pools of BWR and PWR type reactors during severe accidents. Important codes in this field are BUSCA, SPARC and SUPRA. The present paper summarizes the models for scrubbing of gaseous Iodine components in these codes, discusses the experimental validation, and gives an assessment of the state of knowledge reached and the open questions which persist. The retention of gaseous Iodine components is modelled by the various codes in a very heterogeneous manner. Differences show up in the chemical species considered, the treatment of mass transfer boundary layers on the gaseous and liquid sides, the gas-liquid interface geometry, calculation of equilibrium concentrations and numerical procedures. Especially important is the determination of the pool water pH value. This value is affected by basic aerosols deposited in the water, e.g. Cesium and Rubidium compounds. A consistent model requires a mass balance of these compounds in the pool, thus effectively coupling the pool scrubbing phenomena of aerosols and gaseous Iodine species. Since the water pool conditions are also affected by drainage flow of condensate water from different regions in the containment, and desorption of dissolved gases on the pool surface is determined by the gas concentrations above the pool, some basic limitations of specialized pool scrubbing codes are given. The paper draws conclusions about the necessity of coupling between containment thermal-hydraulics and pool scrubbing models, and proposes ways of further simulation model development in order to improve source term predictions. (author) 2 tabs., refs.

  9. Effect of Beetroot Juice Supplementation on Aerobic Response during Swimming

    Directory of Open Access Journals (Sweden)

    Marco Pinna

    2014-01-01

    Full Text Available The beneficial effects of beetroot juice supplementation (BJS have been tested during cycling, walking, and running. The purpose of the present study was to investigate whether BJS can also improve performance in swimmers. Fourteen moderately trained male master swimmers were recruited and underwent two incremental swimming tests randomly assigned in a pool during which workload, oxygen uptake (VO2, carbon dioxide production (VCO2, pulmonary ventilation (VE, and aerobic energy cost (AEC of swimming were measured. One was a control swimming test (CSW and the other a swimming test after six days of BJS (0.5l/day organic beetroot juice containing about 5.5 mmol of NO3−. Results show that workload at anaerobic threshold was significantly increased by BJS as compared to the CSW test (6.3 ± 1 and 6.7 ± 1.1 kg during the CSW and the BJS test respectively. Moreover, AEC was significantly reduced during the BJS test (1.9 ± 0.5 during the SW test vs. 1.7 ± 0.3 kcal·kg−1·h−1 during the BJS test. The other variables lacked a statistically significant effect with BJS. The present investigation provides evidence that BJS positively affects performance of swimmers as it reduces the AEC and increases the workload at anaerobic threshold.

  10. Socioeconomic environment, availability of sports facilities, and jogging, swimming and gym use.

    Science.gov (United States)

    Pascual, Cruz; Regidor, Enrique; Martínez, David; Elisa Calle, M; Domínguez, Vicente

    2009-06-01

    The aim of the study was to evaluate the association of the availability of sports facilities and socioeconomic environment with jogging, swimming and gym use in Spain. The indicators of availability of sports facilities were the number of swimming pools and the number of gyms per 10,000 population. The indicators of socioeconomic environment were average provincial income and provincial unemployment rate. The number of sports facilities was not related with either swimming or gym use and the indicators of socioeconomic environment were not associated with swimming in either sex, or with gym use in men. The findings of this study do not support the hypotheses proposed in previous investigations to explain the consistent relation between socioeconomic environment and lack of physical activity.

  11. Ageing implementation and refurbishment development at the IEA-R1 nuclear research reactor: a 15 years experience

    Energy Technology Data Exchange (ETDEWEB)

    Cardenas, Jose Patricio N.; Ricci Filho, Walter; Carvalho, Marcos R. de; Berretta, Jose Roberto; Marra Neto, Adolfo, E-mail: ahiru@ipen.b, E-mail: wricci@ipen.b, E-mail: carvalho@ipen.b, E-mail: jrretta@ipen.b, E-mail: amneto@ipen.b [Instituto de Pesquisas Energeticas e Nucleares (IPEN/CNEN-SP), Sao Paulo, SP (Brazil)

    2011-07-01

    IPEN (Instituto de Pesquisas Energeticas e Nucleares) is a nuclear research center established into the Secretary of Science and Technology from the government of the state of Sao Paulo, and administered both technically and financially by Comissao Nacional de Energia Nuclear (CNEN), a federal government organization under the Ministry of Science and Technology. The institute is located inside the campus of the University of Sao Paulo, Sao Paulo city, Brazil. One of major nuclear facilities at IPEN is the IEA-R1 nuclear research reactor. It is the unique Brazilian research reactor with substantial power level suitable for application with research in physics, chemistry, biology and engineering, as well as radioisotope production for medical and other applications. Designed and built by Babcok-Wilcox, in accordance with technical specifications established by the Brazilian Nuclear Energy Commission, and financed by the US Atoms for Peace Program, it is a swimming pool type reactor, moderated and cooled by light water and uses graphite and beryllium as reflector elements. The first criticality was achieved on September 16, 1957 and the reactor is currently operating at 4.0 MW on a 64h per week cycle. Since 1996, an IEA-R1 reactor ageing study was established at the Research Reactor Center (CRPq) related with general deterioration of components belonging to some operational systems, as cooling towers from secondary cooling system, piping and pumps, sample irradiation devices, radiation monitoring system, fuel elements, rod drive mechanisms, nuclear and process instrumentation and safety operational system. Although basic structures are almost the same as the original design, several improvements and modifications in components, systems and structures had been made along reactor life. This work aims to show the development of the ageing program in the IEA-R1 reactor and the upgrading (modernization) that was carried out, concerning several equipment and system in the

  12. System Wide Information Management (SWIM)

    Science.gov (United States)

    Hritz, Mike; McGowan, Shirley; Ramos, Cal

    2004-01-01

    This viewgraph presentation lists questions regarding the implementation of System Wide Information Management (SWIM). Some of the questions concern policy issues and strategies, technology issues and strategies, or transition issues and strategies.

  13. Swim pressure of active matter

    Science.gov (United States)

    Takatori, Sho; Yan, Wen; Brady, John; Caltech Team

    2014-11-01

    Through their self-motion, all active matter systems generate a unique ``swim pressure'' that is entirely athermal in origin. This new source for the active stress exists at all scales in both living and nonliving active systems, and also applies to larger organisms where inertia is important (i.e., the Stokes number is not small). Here we explain the origin of the swim stress and develop a simple thermodynamic model to study the self-assembly and phase separation in active soft matter. Our new swim stress perspective can help analyze and exploit a wide class of active soft matter, from swimming bacteria and catalytic nanobots, schools of fish and birds, and molecular motors that activate the cellular cytoskeleton.

  14. Amoeboid swimming in a channel

    CERN Document Server

    Wu, Hao; Hu, W -F; Thiébaud, M; Rafaï, S; Peyla, P; Lai, M -C; Misbah, C

    2016-01-01

    Several micro-organisms, such as bacteria, algae, or spermatozoa, use flagellum or cilium activity to swim in a fluid. Many other organisms use rather ample shape deformation, described as amoeboid, to propel themselves, either crawling on a substrate or swimming. Many eukaryotic cells were believed to require an underlying substratum to migrate (crawl) by using ample membrane deformation (like blebbing). There is now an increasing evidence that a large variety of cells (including those of the immune system) can migrate without the assistance of focal adhesion, and can perform swimming as efficiently as crawling. This paper deals with a detailed analysis of amoeboid swimming in a confined fluid, by modeling the swimmer as an inextensible membrane deploying local active forces. The swimmer exhibits a rich behavior: it can settle into a straight trajectory in the channel, or can navigate from one wall to the other, depending on confinement. Furthermore, the nature of the swimmer is found to be affected by the c...

  15. Fluid dynamics: Swimming across scales

    Science.gov (United States)

    Baumgart, Johannes; Friedrich, Benjamin M.

    2014-10-01

    The myriad creatures that inhabit the waters of our planet all swim using different mechanisms. Now, a simple relation links key physical observables of underwater locomotion, on scales ranging from millimetres to tens of metres.

  16. Is paramecium swimming autonomic?

    Science.gov (United States)

    Bandyopadhyay, Promode R.; Toplosky, Norman; Hansen, Joshua

    2010-11-01

    We seek to explore if the swimming of paramecium has an underlying autonomic mechanism. Such robotic elements may be useful in capturing the disturbance field in an environment in real time. Experimental evidence is emerging that motion control neurons of other animals may be present in paramecium as well. The limit cycle determined using analog simulation of the coupled nonlinear oscillators of olivo-cerebellar dynamics (ieee joe 33, 563-578, 2008) agrees with the tracks of the cilium of a biological paramecium. A 4-motor apparatus has been built that reproduces the kinematics of the cilium motion. The motion of the biological cilium has been analyzed and compared with the results of the finite element modeling of forces on a cilium. The modeling equates applied torque at the base of the cilium with drag, the cilium stiffness being phase dependent. A low friction pendulum apparatus with a multiplicity of electromagnetic actuators is being built for verifying the maps of the attractor basin computed using the olivo-cerebellar dynamics for different initial conditions. Sponsored by ONR 33.

  17. The Association between Anthropometric Variables, Functional Movement Screen Scores and 100 m Freestyle Swimming Performance in Youth Swimmers

    OpenAIRE

    Daisy Bond; Laura Goodson; Samuel W. Oxford; Nevill, Alan M.; Michael J. Duncan

    2015-01-01

    This study examined the association between anthropometric variables, Functional Movement Screen (FMS) scores and 100 m freestyle swimming performance in early adolescent swimmers. Fifty competitive, national level, youth swimmers (21 males, 29 females, mean age ± SD = 13.5 ± 1.5 years, age range 11–16 years) performed an “all-out” 100 m freestyle (front crawl) swim as fast as they could in a 50 m pool. A median divide for 100 m timed swim was also used to divide the sample into faster or slo...

  18. An unadjusted 25 group neutron cross section set for fast reactor core calculations from JENDL-2 library

    Energy Technology Data Exchange (ETDEWEB)

    Devan, K.; Gopalakrishnan, V.; Lee, S.M. [Nuclear Data Section Indira Ganhi Centre for Atomic Research, Tamilnadu (India)

    1994-12-31

    We have created a 25 group neutron cross section set (IGCJENDL) for nuclides of interest to LMFBRs from the Japanese Evaluated Nuclear Data Library - Version 2 (JENDL-2) in the format of French adjusted Cadarache Version 2 set (1969). The integral validation of IGCJENDL set was done by analyzing nine fast critical assemblies proposed by Cross Section Evaluation Working Group (CSEWG). The calculated integral parameters agreed reasonably well with the reported measured values. It is found that this set predicts the integral parameters, k-eff in particular, close to that predicted by adjusted CARNAVAL IV (French) or BNAB-78 (Russian) sets, for a 1200 MWe theoretical benchmark, representing a large power reactor.

  19. Nutrition for swimming.

    Science.gov (United States)

    Shaw, Gregory; Boyd, Kevin T; Burke, Louise M; Koivisto, Anu

    2014-08-01

    Swimming is a sport that requires considerable training commitment to reach individual performance goals. Nutrition requirements are specific to the macrocycle, microcycle, and individual session. Swimmers should ensure suitable energy availability to support training while maintaining long term health. Carbohydrate intake, both over the day and in relation to a workout, should be manipulated (3-10 g/kg of body mass/day) according to the fuel demands of training and the varying importance of undertaking these sessions with high carbohydrate availability. Swimmers should aim to consume 0.3 g of high-biological-value protein per kilogram of body mass immediately after key sessions and at regular intervals throughout the day to promote tissue adaptation. A mixed diet consisting of a variety of nutrient-dense food choices should be sufficient to meet the micronutrient requirements of most swimmers. Specific dietary supplements may prove beneficial to swimmers in unique situations, but should be tried only with the support of trained professionals. All swimmers, particularly adolescent and youth swimmers, are encouraged to focus on a well-planned diet to maximize training performance, which ensures sufficient energy availability especially during periods of growth and development. Swimmers are encouraged to avoid rapid weight fluctuations; rather, optimal body composition should be achieved over longer periods by modest dietary modifications that improve their food choices. During periods of reduced energy expenditure (taper, injury, off season) swimmers are encouraged to match energy intake to requirement. Swimmers undertaking demanding competition programs should ensure suitable recovery practices are used to maintain adequate glycogen stores over the entirety of the competition period.

  20. Swimming and Persons with Mild Persistant Asthma

    Directory of Open Access Journals (Sweden)

    Mirjana Arandelovic

    2007-01-01

    Full Text Available The aim of our study was to analyze the effect of recreational swimming on lung function and bronchial hyperresponsiveness (BHR in patients with mild persistent asthma. This study included 65 patients with mild persistent asthma, who were divided into two groups: experimental group A (n = 45 and control group B (n = 20. Patients from both groups were treated with low doses of inhaled corticosteroids (ICS and short-acting β2 agonists salbutamol as needed. Our program for patients in group A was combined asthma education with swimming (twice a week on a 1-h basis for the following 6 months. At the end of the study, in Group A, we found a statistically significant increase of lung function parameters FEV1 (forced expiratory volume in 1 sec (3.55 vs. 3.65 (p < 0.01, FVC (forced vital capacity (4.27 vs. 4.37 (p < 0.05, PEF (peak expiratory flow (7.08 vs. 7.46 (p < 0.01, and statistically significant decrease of BHR (PD20 0.58 vs. 2.01 (p < 0.001. In Group B, there was a statistically significant improvement of FEV1 3.29 vs. 3.33 (p < 0.05 and although FVC, FEV1/FVC, and PEF were improved, it was not significant. When Groups A and B were compared at the end of the study, there was a statistically significant difference of FVC (4.01 vs. 4.37, FEV1 (3.33 vs. 3.55, PEF (6.79 vs.7.46, and variability (p <0.001, and statistically significantly decreased BHR in Group A (2.01 vs. 1.75 (p < 0.001. Engagement of patients with mild persistent asthma in recreational swimming in nonchlorinated pools, combined with regular medical treatment and education, leads to better improvement of their parameters of lung function and also to more significant decrease of their airway hyperresponsiveness compared to patients treated with traditional medicine

  1. Skin-friction drag analysis from the forced convection modeling in simplified underwater swimming.

    Science.gov (United States)

    Polidori, G; Taïar, R; Fohanno, S; Mai, T H; Lodini, A

    2006-01-01

    This study deals with skin-friction drag analysis in underwater swimming. Although lower than profile drag, skin-friction drag remains significant and is the second and only other contribution to total drag in the case of underwater swimming. The question arises whether varying the thermal gradient between the underwater swimmer and the pool water may modify the surface shear stress distribution and the resulting skin-friction drag acting on a swimmer's body. As far as the authors are aware, such a question has not previously been addressed. Therefore, the purpose of this study was to quantify the effect of this thermal gradient by using the integral formalism applied to the forced convection theory. From a simplified model in a range of pool temperatures (20-30 degrees C) it was demonstrated that, whatever the swimming speeds, a 5.3% reduction in the skin-friction drag would occur with increasing average boundary-layer temperature provided that the flow remained laminar. However, as the majority of the flow is actually turbulent, a turbulent flow analysis leads to the major conclusion that friction drag is a function of underwater speed, leading to a possible 1.5% reduction for fast swimming speeds above 1m/s. Furthermore, simple correlations between the surface shear stress and resulting skin-friction drag are derived in terms of the boundary-layer temperature, which may be readily used in underwater swimming situations.

  2. Swimming and other activities: applied aspects of fish swimming performance

    Science.gov (United States)

    Castro-Santos, Theodore R.; Farrell, A.P.

    2011-01-01

    Human activities such as hydropower development, water withdrawals, and commercial fisheries often put fish species at risk. Engineered solutions designed to protect species or their life stages are frequently based on assumptions about swimming performance and behaviors. In many cases, however, the appropriate data to support these designs are either unavailable or misapplied. This article provides an overview of the state of knowledge of fish swimming performance – where the data come from and how they are applied – identifying both gaps in knowledge and common errors in application, with guidance on how to avoid repeating mistakes, as well as suggestions for further study.

  3. Water Evaporation in Swimming Baths

    DEFF Research Database (Denmark)

    Hyldgård, Carl-Erik

    This paper is publishing measuring results from models and full-scale baths of the evaporation in swimming baths, both public baths and retraining baths. Moreover, the heat balance of the basin water is measured. In addition the full-scale measurements have given many experiences which are repres......This paper is publishing measuring results from models and full-scale baths of the evaporation in swimming baths, both public baths and retraining baths. Moreover, the heat balance of the basin water is measured. In addition the full-scale measurements have given many experiences which...... are represented in instructions for carrying out and running swimming baths. If you follow the instructions you can achieve less investments, less heat consumption and a better comfort to the bathers....

  4. The mouse forced swim test.

    Science.gov (United States)

    Can, Adem; Dao, David T; Arad, Michal; Terrillion, Chantelle E; Piantadosi, Sean C; Gould, Todd D

    2012-01-29

    The forced swim test is a rodent behavioral test used for evaluation of antidepressant drugs, antidepressant efficacy of new compounds, and experimental manipulations that are aimed at rendering or preventing depressive-like states. Mice are placed in an inescapable transparent tank that is filled with water and their escape related mobility behavior is measured. The forced swim test is straightforward to conduct reliably and it requires minimal specialized equipment. Successful implementation of the forced swim test requires adherence to certain procedural details and minimization of unwarranted stress to the mice. In the protocol description and the accompanying video, we explain how to conduct the mouse version of this test with emphasis on potential pitfalls that may be detrimental to interpretation of results and how to avoid them. Additionally, we explain how the behaviors manifested in the test are assessed.

  5. Synchronised Swimming of Two Fish

    CERN Document Server

    Novati, Guido; Alexeev, Dmitry; Rossinelli, Diego; van Rees, Wim M; Koumoutsakos, Petros

    2016-01-01

    We study the fluid dynamics of two fish-like bodies with synchronised swimming patterns. Our studies are based on two-dimensional simulations of viscous incompressible flows. We distinguish between motion patterns that are externally imposed on the swimmers and self-propelled swimmers that learn manoeuvres to achieve certain goals. Simulations of two rigid bodies executing pre-specified motion indicate that flow-mediated interactions can lead to substantial drag reduction and may even generate thrust intermittently. In turn we examine two self-propelled swimmers arranged in a leader-follower configuration, with a-priori specified body-deformations. We find that the swimming of the leader remains largely unaffected, while the follower experiences either an increase or decrease in swimming speed, depending on the initial conditions. Finally, we consider a follower that synchronises its motion so as to minimise its lateral deviations from the leader's path. The leader employs a steady gait while the follower use...

  6. Swimming as a limit cycle

    CERN Document Server

    Jacobs, Henry O

    2012-01-01

    Steady swimming can be characterized as both periodic and stable. These characteristics are the very definition of limit cycles, and so we ask "Can we view swimming as a limit cycle?" In this paper we will find that the answer is "yes". We will define a class of dissipative systems which correspond to the passive dynamics of a body immersed in a Navier-Stokes fluid (i.e. the dynamics of a dead fish). Upon performing reduction by symmetry we will find a hyperbolically stable fixed point which corresponds to the stability of a dead fish in stagnant water. Given a periodic force on the shape of the body we will invoke the persistence theorem to assert the existence of a loop which approximately satisfies the exact equations of motion. If we lift this loop with a phase reconstruction formula we will find that the lifted loops are not loops, but stable trajectories which represent regular periodic motion reminiscent of swimming.

  7. Surface Waters Information Management System (SWIMS)

    Data.gov (United States)

    Kansas Data Access and Support Center — The Surface Waters Information Management System (SWIMS) has been designed to meet multi-agency hydrologic database needs for Kansas. The SWIMS project was supported...

  8. Pressurized Water Reactor Nuclear Power Plant Spent Fuel Pool Spray System Design%压水堆核电站乏燃料池喷淋系统设计

    Institute of Scientific and Technical Information of China (English)

    苏夏

    2013-01-01

      第三代非能动压水堆核电站AP1000中首次为乏燃料池设置了喷淋系统,在超设计基准事故或恐怖袭击导致乏燃料池水排空时,为乏燃料提供冷却。喷淋系统设计中的两个重要指标是喷淋覆盖面积和单位面积有效喷淋流量。设计者应基于喷嘴性能试验结果,根据乏燃料池结构尺寸和乏燃料特性,确定喷淋流量、喷嘴数量和布置方式等参数,完成系统设计,提供足够冷却流量。%  Spray system of spent fuel pool is first designed in AP1000, it can provide spray water to cool the spent fuel in a beyond design basis event or a terror attack that drains the pool. The two most important factors of spray system are the coverage pattern and the effective flow density. The spray flowrate, the nozzle number and their location should be designed based on the spray nozzle test results, the spent fuel pool structure and the spent fuel character to achieve the intent of providing enough cooling.

  9. H Reactor

    Data.gov (United States)

    Federal Laboratory Consortium — The H Reactor was the first reactor to be built at Hanford after World War II.It became operational in October of 1949, and represented the fourth nuclear reactor on...

  10. OPPORTUNITIES FOR PSYCHO-MOTOR SKILLS DEVELOPMENT IN CHILDREN WITH DOWN SYNDROME - ADAPTED SWIMMING -

    Directory of Open Access Journals (Sweden)

    Chera-Ferrario B.

    2012-12-01

    Full Text Available Sport activities have a beneficial effect on the mind and body of any type of person. The benefits of sport are even more evident in children with Down Syndrome, who exhibit a general delay in neuro-motor structures. Our aim was to develop the psycho-motor skills in children with Down Syndrome through adapted swimming exercises. We believe that our involvement in adapted swimming for children with Down Syndrome may help develop certain aspects of psycho-motor abilities. The swimming took place with 6 Down Syndrome children from the Special Needs School in Targoviste, for a period of six months and the children being assisted by volunteer students from the Valahia University Department of Sport in Targoviste.The most important result was the children's delight in coming to the pool and taking part in the swimming lessons. Through the methods and exercises used and the devoted involvement of the volunteers, the children developed great levels of trust and courage and learned to swim using only aids. After performing motor skill tests on the children, we observed a general growth in the motor skills monitored.Continuation of the adapted swimming is very important in order to mobilize the skills obtained and continue development of psycho-motor abilities.

  11. 36 CFR 327.5 - Swimming.

    Science.gov (United States)

    2010-07-01

    ... 36 Parks, Forests, and Public Property 3 2010-07-01 2010-07-01 false Swimming. 327.5 Section 327.5 Parks, Forests, and Public Property CORPS OF ENGINEERS, DEPARTMENT OF THE ARMY RULES AND REGULATIONS... Swimming. (a) Swimming, wading, snorkeling or scuba diving at one's own risk is permitted, except...

  12. 36 CFR 331.10 - Swimming.

    Science.gov (United States)

    2010-07-01

    ... 36 Parks, Forests, and Public Property 3 2010-07-01 2010-07-01 false Swimming. 331.10 Section 331.10 Parks, Forests, and Public Property CORPS OF ENGINEERS, DEPARTMENT OF THE ARMY REGULATIONS..., KENTUCKY AND INDIANA § 331.10 Swimming. Swimming is prohibited unless authorized in writing by the...

  13. 43 CFR 423.36 - Swimming.

    Science.gov (United States)

    2010-10-01

    ... 43 Public Lands: Interior 1 2010-10-01 2010-10-01 false Swimming. 423.36 Section 423.36 Public Lands: Interior Regulations Relating to Public Lands BUREAU OF RECLAMATION, DEPARTMENT OF THE INTERIOR... Swimming. (a) You may swim, wade, snorkel, scuba dive, raft, or tube at your own risk in Reclamation...

  14. Undulatory fish swimming : from muscles to flow

    NARCIS (Netherlands)

    Müller, U.K.; Leeuwen, van J.L.

    2006-01-01

    Undulatory swimming is employed by many fish for routine swimming and extended sprints. In this biomechanical review, we address two questions: (i) how the fish's axial muscles power swimming; and (ii) how the fish's body and fins generate thrust. Fish have adapted the morphology of their axial musc

  15. PDA: Pooled DNA analyzer

    Directory of Open Access Journals (Sweden)

    Lin Chin-Yu

    2006-04-01

    Full Text Available Abstract Background Association mapping using abundant single nucleotide polymorphisms is a powerful tool for identifying disease susceptibility genes for complex traits and exploring possible genetic diversity. Genotyping large numbers of SNPs individually is performed routinely but is cost prohibitive for large-scale genetic studies. DNA pooling is a reliable and cost-saving alternative genotyping method. However, no software has been developed for complete pooled-DNA analyses, including data standardization, allele frequency estimation, and single/multipoint DNA pooling association tests. This motivated the development of the software, 'PDA' (Pooled DNA Analyzer, to analyze pooled DNA data. Results We develop the software, PDA, for the analysis of pooled-DNA data. PDA is originally implemented with the MATLAB® language, but it can also be executed on a Windows system without installing the MATLAB®. PDA provides estimates of the coefficient of preferential amplification and allele frequency. PDA considers an extended single-point association test, which can compare allele frequencies between two DNA pools constructed under different experimental conditions. Moreover, PDA also provides novel chromosome-wide multipoint association tests based on p-value combinations and a sliding-window concept. This new multipoint testing procedure overcomes a computational bottleneck of conventional haplotype-oriented multipoint methods in DNA pooling analyses and can handle data sets having a large pool size and/or large numbers of polymorphic markers. All of the PDA functions are illustrated in the four bona fide examples. Conclusion PDA is simple to operate and does not require that users have a strong statistical background. The software is available at http://www.ibms.sinica.edu.tw/%7Ecsjfann/first%20flow/pda.htm.

  16. Physical and energy requirements of competitive swimming events.

    Science.gov (United States)

    Pyne, David B; Sharp, Rick L

    2014-08-01

    The aquatic sports competitions held during the summer Olympic Games include diving, open-water swimming, pool swimming, synchronized swimming, and water polo. Elite-level performance in each of these sports requires rigorous training and practice to develop the appropriate physiological, biomechanical, artistic, and strategic capabilities specific to each sport. Consequently, the daily training plans of these athletes are quite varied both between and within the sports. Common to all aquatic athletes, however, is that daily training and preparation consumes several hours and involves frequent periods of high-intensity exertion. Nutritional support for this high-level training is a critical element of the preparation of these athletes to ensure the energy and nutrient demands of the training and competition are met. In this article, we introduce the fundamental physical requirements of these sports and specifically explore the energetics of human locomotion in water. Subsequent articles in this issue explore the specific nutritional requirements of each aquatic sport. We hope that such exploration will provide a foundation for future investigation of the roles of optimal nutrition in optimizing performance in the aquatic sports.

  17. Hydrodynamics of freely swimming flagellates

    Science.gov (United States)

    Dolger, Julia; Nielsen, Lasse Tor; Kiorboe, Thomas; Bohr, Tomas; Andersen, Anders

    2016-11-01

    Flagellates are a diverse group of unicellular organisms forming an important part of the marine ecosystem. The arrangement of flagella around the cell serves as a key trait optimizing and compromising essential functions. With micro-particle image velocimetry we observed time-resolved near-cell flows around freely swimming flagellates, and we developed an analytical model based on the Stokes flow around a solid sphere propelled by a variable number of differently placed, temporally varying point forces, each representing one flagellum. The model allows us to reproduce the observed flow patterns and swimming dynamics, and to extract quantities such as swimming velocities and prey clearance rates as well as flow disturbances revealing the organism to flow-sensing predators. Our results point to optimal flagellar arrangements and beat patterns, and essential trade-offs. For biflagellates with two symmetrically arranged flagella we contrasted two species using undulatory and ciliary beat patterns, respectively, and found breast-stroke type beat patterns with equatorial power strokes to be favorable for fast as well as quiet swimming. The Centre for Ocean Life is a VKR Centre of Excellence supported by the Villum Foundation.

  18. Sports Medicine Meets Synchronized Swimming.

    Science.gov (United States)

    Wenz, Betty J.; And Others

    This collection of articles contains information about synchronized swimming. Topics covered include general physiology and cardiovascular conditioning, flexibility exercises, body composition, strength training, nutrition, coach-athlete relationships, coping with competition stress and performance anxiety, and eye care. Chapters are included on…

  19. Shape Optimization of Swimming Sheets

    Energy Technology Data Exchange (ETDEWEB)

    Wilkening, J.; Hosoi, A.E.

    2005-03-01

    The swimming behavior of a flexible sheet which moves by propagating deformation waves along its body was first studied by G. I. Taylor in 1951. In addition to being of theoretical interest, this problem serves as a useful model of the locomotion of gastropods and various micro-organisms. Although the mechanics of swimming via wave propagation has been studied extensively, relatively little work has been done to define or describe optimal swimming by this mechanism.We carry out this objective for a sheet that is separated from a rigid substrate by a thin film of viscous Newtonian fluid. Using a lubrication approximation to model the dynamics, we derive the relevant Euler-Lagrange equations to optimize swimming speed and efficiency. The optimization equations are solved numerically using two different schemes: a limited memory BFGS method that uses cubic splines to represent the wave profile, and a multi-shooting Runge-Kutta approach that uses the Levenberg-Marquardt method to vary the parameters of the equations until the constraints are satisfied. The former approach is less efficient but generalizes nicely to the non-lubrication setting. For each optimization problem we obtain a one parameter family of solutions that becomes singular in a self-similar fashion as the parameter approaches a critical value. We explore the validity of the lubrication approximation near this singular limit by monitoring higher order corrections to the zeroth order theory and by comparing the results with finite element solutions of the full Stokes equations.

  20. Swimming bacteria in liquid crystal

    Science.gov (United States)

    Sokolov, Andrey; Zhou, Shuang; Aranson, Igor; Lavrentovich, Oleg

    2014-03-01

    Dynamics of swimming bacteria can be very complex due to the interaction between the bacteria and the fluid, especially when the suspending fluid is non-Newtonian. Placement of swimming bacteria in lyotropic liquid crystal produces a new class of active materials by combining features of two seemingly incompatible constituents: self-propelled live bacteria and ordered liquid crystals. Here we present fundamentally new phenomena caused by the coupling between direction of bacterial swimming, bacteria-triggered flows and director orientations. Locomotion of bacteria may locally reduce the degree of order in liquid crystal or even trigger nematic-isotropic phase transition. Microscopic flows generated by bacterial flagella disturb director orientation. Emerged birefringence patterns allow direct optical observation and quantitative characterization of flagella dynamics. At high concentration of bacteria we observed the emergence of self-organized periodic texture caused by bacteria swimming. Our work sheds new light on self-organization in hybrid bio-mechanical systems and can lead to valuable biomedical applications. Was supported by the US DOE, Office of Basic Energy Sciences, Division of Materials Science and Engineering, under the Contract No. DE AC02-06CH11357.

  1. What’s In the Pool? (A Cup of Health with CDC)

    Centers for Disease Control (CDC) Podcasts

    2013-05-30

    As summer approaches, more and more people will head to the pool, but dangers lurk in the form of waterborne diseases. In this podcast, Michele Hlavsa discusses ways to avoid waterborne diseases while swimming.  Created: 5/30/2013 by MMWR.   Date Released: 5/30/2013.

  2. 76 FR 62605 - Virginia Graeme Baker Pool and Spa Safety Act; Interpretation of Unblockable Drain

    Science.gov (United States)

    2011-10-11

    ... 19, 2008. The VGB Act's purpose is to prevent suction entrapment by swimming pool and spa drains and...; Suction-limiting vent system; Gravity drainage system; Automatic pump shut-off system; Drain disablement.... A ] drain is ``unblockable'' if the suction outlet, including the sump, has a perforated (open)...

  3. A simplified model of decontamination by BWR steam suppression pools

    Energy Technology Data Exchange (ETDEWEB)

    Powers, D.A.

    1997-05-01

    Phenomena that can decontaminate aerosol-laden gases sparging through steam suppression pools of boiling water reactors during reactor accidents are described. Uncertainties in aerosol properties, aerosol behavior within gas bubbles, and bubble behavior in plumes affect predictions of decontamination by steam suppression pools. Uncertainties in the boundary and initial conditions that are dictated by the progression of severe reactor accidents and that will affect predictions of decontamination by steam suppression pools are discussed. Ten parameters that characterize boundary and initial condition uncertainties, nine parameters that characterize aerosol property and behavior uncertainties, and eleven parameters that characterize uncertainties in the behavior of bubbles in steam suppression pools are identified. Ranges for the values of these parameters and subjective probability distributions for parametric values within the ranges are defined. These uncertain parameters are used in Monte Carlo uncertainty analyses to develop uncertainty distributions for the decontamination that can be achieved by steam suppression pools and the size distribution of aerosols that do emerge from such pools. A simplified model of decontamination by steam suppression pools is developed by correlating features of the uncertainty distributions for total decontamination factor, DF(total), mean size of emerging aerosol particles, d{sub p}, and the standard deviation of the emerging aerosol size distribution, {sigma}, with pool depth, H. Correlations of the median values of the uncertainty distributions are suggested as the best estimate of decontamination by suppression pools. Correlations of the 10 percentile and 90 percentile values of the uncertainty distributions characterize the uncertainty in the best estimates. 295 refs., 121 figs., 113 tabs.

  4. Vitamin D Pooling Project

    Science.gov (United States)

    The Vitamin D Pooling Project of Rarer Cancers brought together investigators from 10 cohorts to conduct a large prospective epidemiologic study of the association between vitamin D status and seven rarer cancers.

  5. Micro- and nanorobots swimming in heterogeneous liquids.

    Science.gov (United States)

    Nelson, Bradley J; Peyer, Kathrin E

    2014-09-23

    Essentially all experimental investigations of swimming micro- and nanorobots have focused on swimming in homogeneous Newtonian liquids. In this issue of ACS Nano, Schamel et al. investigate the actuation of "nanopropellers" in a viscoelastic biological gel that illustrates the importance of the size of the nanostructure relative to the gel mesh size. In this Perspective, we shed further light on the swimming performance of larger microrobots swimming in heterogeneous liquids. One of the interesting results of our work is that earlier findings on the swimming performance of motile bacteria in heterogeneous liquids agree, in principle, with our results. We also discuss future research directions that should be pursued in this fascinating interdisciplinary field.

  6. Effects of In-Water Passive Recovery on Sprint Swimming Performance and Heart Rate in Adolescent Swimmers

    Directory of Open Access Journals (Sweden)

    Rafael A. Casuso

    2014-12-01

    Full Text Available The aim of the present study is to test the hypothesis that sprint swimming performance is enhanced by in-water passive recovery (IN after sprint swimming bouts in well-trained adolescent swimmers. Using a randomized crossover study design, twelve well-trained adolescent swimmers performed two tests at the swimming pool after preliminary testing. They performed 5 bouts of 100m all-out swimming separated by 5 minutes of passive rest. Their individual in- or out-of-water passive recovery condition was randomized on the first day. In their second visit to the swimming pool the opposite recovery condition was indicated. More than 60% of the subjects which rested in-water were faster in the 5th bout when compared to the OUT group. However, no significant differences were found in blood lactate when IN and OUT were compared. After the first bout peak heart rate (HR peak was lower in subsequent bouts for IN recovery when compared with OUT (p < 0.001. Thus, coaches and researchers should take into account that IN passive recovery may decrease loss of performance and diminish HR peak during sprint swimming bouts. This is particularly important given the use that many coaches give to HR as a tool in daily training.

  7. Stress corrosion (Astm G30-90 standard) in 08x18H10T stainless steel of nuclear fuel storage pool in WWER reactors; Corrosion bajo esfuerzo (Norma ASTM G30-90) en acero inoxidable 08x18H10T de piscinas de almacenamiento de combustible nuclear en reactores V.V.E.R

    Energy Technology Data Exchange (ETDEWEB)

    Herrera, V.; Zamora R, L. [Centro de Estudios Aplicados al Desarrollo Nuclear (Cuba)

    1997-07-01

    At the water storage of the irradiated nuclear fuel has been an important factor in its management. The actual pools have its walls covered with inoxidable steel and heat exchangers to dissipate the residual heat from fuel. It is essential to control the water purity to eliminate those conditions which aid to the corrosion process in fuel and at related components. The steel used in this research was obtained from an austenitic inoxidizable steel standardized with titanium 08x18H10T (Type 321) similar to one of the two steel coatings used to cover walls and the pools floor. the test consisted in the specimen deformation through an U ply according to the Astm G30-90 standard. The exposition of the deformed specimen it was realized in simulated conditions to the chemical regime used in pools. (Author)

  8. Repairing liner of the reactor; Reparacion del liner del reactor

    Energy Technology Data Exchange (ETDEWEB)

    Aguilar H, F. [ININ, 52045 Ocoyoacac, Estado de Mexico (Mexico)

    2001-07-15

    Due to the corrosion problems of the aluminum coating of the reactor pool, a periodic inspections program by ultrasound to evaluate the advance grade and the corrosion speed was settled down. This inspections have shown the necessity to repair some areas, in those that the slimming is significant, of not making it can arrive to the water escape of the reactor pool. The objective of the repair is to place patches of plates of 1/4 inch aluminum thickness in the areas of the reactor 'liner', in those that it has been detected by ultrasound a smaller thickness or similar to 3 mm. To carry out this the fuels are move (of the core and those that are decaying) to a temporary storage, the structure of the core is confined in a tank that this placed inside the pool of the reactor, a shield is placed in the thermal column and it is completely extracted the water for to leave uncover the 'liner' of the reactor. (Author)

  9. Development of two-dimensional hot pool model

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Yong Bum; Hahn, H. D

    2000-05-01

    During a normal reactor scram, the heat generation is reduced almost instantaneously while the coolant flow rate follows the pump coast-down. This mismatch between power and flow results in a situation where the core flow entering the hot pool is at a lower temperature than the temperature of the bulk pool sodium. This temperature difference leads to thermal stratification. Thermal stratification can occur in the hot pool region if the entering coolant is colder than the existing hot pool coolant and the flow momentum is not large enough to overcome the negative buoyancy force. Since the fluid of hot pool enters IHX{sub s}, the temperature distribution of hot pool can alter the overall system response. Hence, it is necessary to predict the pool coolant temperature distribution with sufficient accuracy to determine the inlet temperature conditions for the IHX{sub s} and its contribution to the net buoyancy head. Therefore, in this study two-dimensional hot pool model is developed instead of existing one-dimensional model to predict the hot pool coolant temperature and velocity distribution more accurately and is applied to the SSC-K code.

  10. Assessment of short-distance breaststroke swimming performance with critical velocity.

    Science.gov (United States)

    Abe, Daijiro; Tokumaru, Hiroaki; Niihata, Shigemitsu; Muraki, Satoshi; Fukuoka, Yoshiyuki; Usui, Sachio; Yoshida, Takayoshi

    2006-01-01

    For high-velocity running or swimming, the relationship between velocity (v) and its sustainable duration (t) can be described by a hyperbolic relationship: (v - Vcrit)·t = D', where Vcrit is termed critical velocity, and D' is defined as a curvature constant of the hyperbolic curve. The purposes of this study were to examine whether the Vcrit could be applied to evaluate short-distance breaststroke swimming performance and to evaluate the relative contribution of D' in short-distance swimming performance. Eleven male swimmers performed a series of time trials corresponding to 75, 100, and 150-m in an indoor 50-m swimming pool. The observed records were calculated into average velocities of each event to determine Vcrit and D'. After the determination of Vcrit and D', all subjects performed 50-m time trial on another day. A maximal anaerobic power test using cycle ergometer was also performed in the laboratory. The average velocity of the 50-m time trial significantly correlated with the obtained Vcrit, but not with D'. D' was significantly correlated with the residual error, calculated from the regression analysis for the relationship between Vcrit and the average velocities of 50-m time trial. A cluster analysis showed that most of the subjects were classified as Vcrit dependency when performing 50-m time trial. Those results indicated that Vcrit could be applied to evaluate short-distance swimming performance, and it determined around 80% of the short-distance breaststroke swimming performance. Key PointsFor high-velocity running or swimming, the relationship between velocity (v) and its sustainable duration (t) can be described by a hyperbolic relationship: (v - Vcrit)·t = D', where Vcrit is termed critical velocity, and D' is defined as a curvature constant of the hyperbolic curve. The D' contributed only around 20% of the breaststroke swimming performance even in a short-distance event.Critical velocity determined around 80% of 50-m breaststroke swimming

  11. Can polish university female students swim?

    Directory of Open Access Journals (Sweden)

    Podstawski Robert

    2013-06-01

    Full Text Available Background and aim of the work: There are only few studies in Polish and foreign literature providing solid information on swimming skills of university students. The aim of the study carried out at the University of Warmia & Mazury in Olsztyn was to determine swimming skills of Polish university female students starting their studies. Material and methods: The study was conducted in 2012 on 298 female students of the 1 st year course, at the age of 19 – 20. Anonymous questionnaire was used in the research. Results: It has been shown that almost 72% of the women could not swim at all, and 26% swam poorly. Within the group of women able to swim, the greatest percentage was set by women using classical style (49% and “their own” one (27% and only 13% of the students used crawl, 9% - back stroke and 2% - butterfly style. Of all the women declaring swimming abilities, the biggest percentage (16% could cover the distance of only 20 – 50 m; fewer students (6% covered the distance of 50 – 100 m; and 5% could swim only 20 m. Only a marginal number of students (2% could cover the distance from 100 to 1000 m; none could swim more than 1000 m. Conclusions: The study showed a very pessimistic picture of swimming skills of Polish university female students in respect of the number of women able to swim, their knowledge of swimming styles, and the length of the covered distance.

  12. Swimming versus swinging in spacetime

    CERN Document Server

    Guéron, E; Matsas, G E A; Gueron, Eduardo; Maia, Clovis A. S.; Matsas, George E. A.

    2006-01-01

    Wisdom has recently unveiled a new relativistic effect, called ``spacetime swimming'', where quasi-rigid free bodies in curved spacetimes can "speed up", "slow down" or "deviate" their falls by performing "local" cyclic shape deformations. We show here that for fast enough cycles this effect dominates over a non-relativistic related one, named here ``space swinging'', where the fall is altered through "nonlocal" cyclic deformations in Newtonian gravitational fields. We expect, therefore, to clarify the distinction between both effects leaving no room to controversy. Moreover, the leading contribution to the swimming effect predicted by Wisdom is enriched with a higher order term and the whole result is generalized to be applicable in cases where the tripod is in large red-shift regions.

  13. Team swimming in ant spermatozoa.

    Science.gov (United States)

    Pearcy, Morgan; Delescaille, Noémie; Lybaert, Pascale; Aron, Serge

    2014-06-01

    In species where females mate promiscuously, competition between ejaculates from different males to fertilize the ova is an important selective force shaping many aspects of male reproductive traits, such as sperm number, sperm length and sperm-sperm interactions. In eusocial Hymenoptera (bees, wasps and ants), males die shortly after mating and their reproductive success is ultimately limited by the amount of sperm stored in the queen's spermatheca. Multiple mating by queens is expected to impose intense selective pressure on males to optimize the transfer of sperm to the storage organ. Here, we report a remarkable case of cooperation between spermatozoa in the desert ant Cataglyphis savignyi. Males ejaculate bundles of 50-100 spermatozoa. Sperm bundles swim on average 51% faster than solitary sperm cells. Team swimming is expected to increase the amount of sperm stored in the queen spermatheca and, ultimately, enhance male posthumous fitness.

  14. Effects of in-water passive recovery on sprint swimming performance and heart rate in adolescent swimmers.

    Science.gov (United States)

    Casuso, Rafael A; Martínez-López, Emilio; Hita-Contreras, Fidel; Ruiz-Cazalilla, Irene; Cruz-Díaz, David; Martínez-Amat, Antonio

    2014-12-01

    The aim of the present study is to test the hypothesis that sprint swimming performance is enhanced by in-water passive recovery (IN) after sprint swimming bouts in well-trained adolescent swimmers. Using a randomized crossover study design, twelve well-trained adolescent swimmers performed two tests at the swimming pool after preliminary testing. They performed 5 bouts of 100m all-out swimming separated by 5 minutes of passive rest. Their individual in- or out-of-water passive recovery condition was randomized on the first day. In their second visit to the swimming pool the opposite recovery condition was indicated. More than 60% of the subjects which rested in-water were faster in the 5th bout when compared to the OUT group. However, no significant differences were found in blood lactate when IN and OUT were compared. After the first bout peak heart rate (HR peak) was lower in subsequent bouts for IN recovery when compared with OUT (p recovery may decrease loss of performance and diminish HR peak during sprint swimming bouts. This is particularly important given the use that many coaches give to HR as a tool in daily training. Key pointsIn-water passive recovery minimizes the loss of performance during high intensity swimmingMaximal HR is significantly reduced by in-water recoveryCoaches should take this information into account when using HR to control swimming intensityFuture research should study long-term effects induced by in-water passive recovery.

  15. Reactor Physics

    Energy Technology Data Exchange (ETDEWEB)

    Ait Abderrahim, A

    2001-04-01

    The Reactor Physics and MYRRHA Department of SCK-CEN offers expertise in various areas of reactor physics, in particular in neutronics calculations, reactor dosimetry, reactor operation, reactor safety and control and non-destructive analysis of reactor fuel. This expertise is applied in the Department's own research projects in the VENUS critical facility, in the BR1 reactor and in the MYRRHA project (this project aims at designing a prototype Accelerator Driven System). Available expertise is also used in programmes external to the Department such as the reactor pressure steel vessel programme, the BR2 reactor dosimetry, and the preparation and interpretation of irradiation experiments by means of neutron and gamma calculations. The activities of the Fuzzy Logic and Intelligent Technologies in Nuclear Science programme cover several domains outside the department. Progress and achievements in these topical areas in 2000 are summarised.

  16. Synchronized Swimming of Two Fish

    Science.gov (United States)

    Koumoutsakos, Petros; Novati, Guido; Abbati, Gabriele; Hejazialhosseini, Babak; van Rees, Wim

    2015-11-01

    We present simulations of two, self-propelled, fish-like swimmers that perform synchronized moves in a two-dimensional, viscous fluid. The swimmers learn to coordinate by receiving a reward for their synchronized actions. We analyze the swimming patterns emerging for different rewards in terms of their hydrodynamic efficiency and artistic impression. European Research Council (ERC) Advanced Investigator Award (No. 2-73985-14).

  17. Experiments and Characterization of the Two-Phase Flow Driven Particulate Debris Spreading in the Pool

    OpenAIRE

    Konovalenko, Alexander; Basso, Simone; Kudinov, Pavel

    2014-01-01

    Melt fragmentation, quenching and long term coolability in a deep pool of water under reactor vessel are employed as a severe accident mitigation strategy in several designs of light water reactors. Success of the strategy is contingent upon effectiveness of natural circulation in removing the decay heat generated by the porous debris bed. Geometrical configuration of the bed is one of the factors which affect coolability of the bed. Boiling and two-phase turbulent flows in the pool serve as ...

  18. Cetacean Swimming with Prosthetic Limbs

    Science.gov (United States)

    Bode-Oke, Ayodeji; Ren, Yan; Dong, Haibo; Fish, Frank

    2016-11-01

    During entanglement in fishing gear, dolphins can suffer abrasions and amputations of flukes and fins. As a result, if the dolphin survives the ordeal, swimming performance is altered. Current rehabilitation technques is the use of prosthesis to regain swimming ability. In this work, analyses are focused on two dolphins with locomotive impairment; Winter (currently living in Clearwater Marine Aquarium in Florida) and Fuji (lived in Okinawa Churaumi Aquarium in Japan). Fuji lost about 75% of its fluke surface to necrosis (death of cells) and Winter lost its tail due to amputation. Both dolphins are aided by prosthetic tails that mimic the shape of a real dolphin tail. Using 3D surface reconstruction techniques and a high fidelity Computational Fluid Dynamics (CFD) flow solver, we were able to elucidate the kinematics and hydrodynamics and fluke deformation of these swimmers to clarify the effectiveness of prostheses in helping the dolphins regain their swimming ability. Associated with the performance, we identified distinct features in the wake structures that can explain this gap in the performance compared to a healthy dolphin. This work was supported by ONR MURI Grant Number N00014-14-1-0533.

  19. Nutritional recommendations for synchronized swimming.

    Science.gov (United States)

    Robertson, Sherry; Benardot, Dan; Mountjoy, Margo

    2014-08-01

    The sport of synchronized swimming is unique, because it combines speed, power, and endurance with precise synchronized movements and high-risk acrobatic maneuvers. Athletes must train and compete while spending a great amount of time underwater, upside down, and without the luxury of easily available oxygen. This review assesses the scientific evidence with respect to the physiological demands, energy expenditure, and body composition in these athletes. The role of appropriate energy requirements and guidelines for carbohydrate, protein, fat, and micronutrients for elite synchronized swimmers are reviewed. Because of the aesthetic nature of the sport, which prioritizes leanness, the risks of energy and macronutrient deficiencies are of significant concern. Relative Energy Deficiency in Sport and disordered eating/eating disorders are also of concern for these female athletes. An approach to the healthy management of body composition in synchronized swimming is outlined. Synchronized swimmers should be encouraged to consume a well-balanced diet with sufficient energy to meet demands and to time the intake of carbohydrate, protein, and fat to optimize performance and body composition. Micronutrients of concern for this female athlete population include iron, calcium, and vitamin D. This article reviews the physiological demands of synchronized swimming and makes nutritional recommendations for recovery, training, and competition to help optimize athletic performance and to reduce risks for weight-related medical issues that are of particular concern for elite synchronized swimmers.

  20. Use of employments on swimming in pulling in and restoration microcycles in the training process of the highly skilled sportsmen of the highly skilled heavy weight sambo wrestlers

    Directory of Open Access Journals (Sweden)

    Zakorko I.P.

    2013-01-01

    Full Text Available Expedience of the use of the sporting and health swimming is grounded in precontest preparation of the highly skilled sportsmen unarmed self-defence. 10 sportsmen took part in research (weight over 90 kg. Offered to recommendation on the use of swimming in renewal of sportsmen after the competition and trainings loadings. On employments, swimming was utillized a method crawl on a breast and by a method breast-stroke. Length of path of pool is 25 meters. The level of influence of trainings is set on swimming of different orientation on the general consisting of the sportsman unarmed self-defence of context of preparation and renewal during the specialized competition activity. It is recommended in training on swimming to utillize overcoming at full pelt of cutting-off 250 meters in the mode to 5 minutes (time of competition fight is in the fight of sambo-5 of minutes.

  1. Reactor safeguards

    CERN Document Server

    Russell, Charles R

    1962-01-01

    Reactor Safeguards provides information for all who are interested in the subject of reactor safeguards. Much of the material is descriptive although some sections are written for the engineer or physicist directly concerned with hazards analysis or site selection problems. The book opens with an introductory chapter on radiation hazards, the construction of nuclear reactors, safety issues, and the operation of nuclear reactors. This is followed by separate chapters that discuss radioactive materials, reactor kinetics, control and safety systems, containment, safety features for water reactor

  2. Reactor operation

    CERN Document Server

    Shaw, J

    2013-01-01

    Reactor Operation covers the theoretical aspects and design information of nuclear reactors. This book is composed of nine chapters that also consider their control, calibration, and experimentation.The opening chapters present the general problems of reactor operation and the principles of reactor control and operation. The succeeding chapters deal with the instrumentation, start-up, pre-commissioning, and physical experiments of nuclear reactors. The remaining chapters are devoted to the control rod calibrations and temperature coefficient measurements in the reactor. These chapters also exp

  3. The Jules Horowitz reactor (JHR), a European material testing reactor (MTR), with extended experimental capabilities

    Energy Technology Data Exchange (ETDEWEB)

    Ballagny, A.; Bergamaschi, Y.; Bouilloux, Y.; Bravo, X.; Guigon, B.; Rommens, M.; Tremodeux, P. [CEA Cadarache, Dir. de l' Energie Nucleaire DEN, 13 - Saint-Paul-lez-Durance (France)]|[CEA Saclay Dir. de l' Energie Nucleaire DEN, 91 - Gif sur Yvette (France)

    2003-07-01

    The Jules Horowitz Reactor (JHR) is the European MTR (Material Testing Reactor) designed to provide, after 2010, the necessary knowledge for keeping the existing power plants in operation and to design innovative reactors types with new objectives such as: minimizing the radioactive waste production, taking into account additional safety requirements, preventing risks of nuclear proliferation... To achieve such an ambitious objective. The JHR is designed with a high flexibility in order to satisfy the current demand from European industry, research and to be able to accommodate future requirements. The JHR will offer a wide range of performances and services in gathering, in a single site at Cadarache, all the necessary functionalities and facilities for an effective production of results: e.g. fuel fabrication laboratories, preparation of the instrumented devices, interpretation of the experiments, modelling. The JHR must rely on a top level scientific environment based on experts teams from CEA and EC and local universities. With a thermal flux of 7,4.10{sup 14} ncm{sup -2} s{sup -1} and a fast flux of 6,4.10{sup 14} ncm{sup -2}s{sup -1}, it is possible to carry out irradiation experiments on materials and fuels whatever the reactor type considered. It will also be possible to carry out locally, fast neutron irradiation to achieve damage effect up to 25 dpa/year. (dpa = displacement per atom.) The study of the fuels behavior under accidental conditions, from analytical experiments, on a limited amount of irradiated fuel, is a major objective of the project. These oriented safety tests are possible by taking into account specific requirements in the design of the facility such as the tightness level of the containment building, the addition of an alpha hot cell and a laboratory for on line fission products measurement. (authors)

  4. Annual report on JEN-1 reactor; Informe periodico del Reactor JEN-1 correspondiente al ano 1971

    Energy Technology Data Exchange (ETDEWEB)

    Montes, J.

    1972-07-01

    In the annual report on the JEN-1 reactor the main features of the reactor operations and maintenance are described. The reactor has been critical for 1831 hours, what means 65,8% of the total working time. Maintenance and pool water contamination have occupied the rest of the time. The maintenance schedule is shown in detail according to three subjects. The main failures and reactor scrams are also described. The daily maximum values of the water activity are given so as the activity of the air in the reactor hall. (Author)

  5. The Future of Pooling.

    Science.gov (United States)

    Young, Peter C.; Fone, Martin

    1997-01-01

    Discusses seven propositions underlying the strategies that insurance pools can, will, and must pursue: (1) risk management versus risk financing; (2) elimination of windfall advantages; (3) the maintenance of market-dominant status; (4) cost leadership; (5) client focus; (6) innovation and diversification; and (7) leadership challenges. A sidebar…

  6. Swimming kinematics of the Florida manatee (Trichechus manatus latirostris): hydrodynamic analysis of an undulatory mammalian swimmer.

    Science.gov (United States)

    Kojeszewski, Tricia; Fish, Frank E

    2007-07-01

    The submerged swimming of the Florida manatee (Trichechus manatus latirostris), a subspecies of the West Indian manatee, was studied by filming individuals as they swam rectilinearly in a large pool at several rehabilitation centers. The swimming was analyzed using videography to detail the kinematics in conjunction with a hydromechanical model to determine the power output (P(t)) and propulsive efficiency (eta(p)). Manatees swam at velocities of 0.06-1.14 m s(-1). Locomotion was accomplished by undulation of the body and caudal fluke. Undulatory locomotion is a rapid and relatively high-powered propulsive mode involved in cruising and migrating by a variety of swimmers. Manatees displayed an undulatory swimming mode by passing a dorso-ventrally oriented traveling wave posteriorly along the body. The propulsive wave traveled at a higher velocity than the forward velocity of the animal. The frequency of the propulsive cycle (f) increased linearly with increasing swimming velocity (U). Amplitude at the tip of the caudal fluke (A) remained constant with respect to U and was 22% of body length. P(t) increased curvilinearly with U. The mean eta(p), expressing the relationship of the thrust power generated by the paddle-shaped caudal fluke to the total mechanical power, was 0.73. The maximum eta(p) was 0.82 at 0.95 m s(-1). Despite use of a primitive undulatory swimming mode and paddle-like fluke for propulsion, the manatee is capable of swimming with a high efficiency but lower power outputs compared with the oscillatory movements of the high-aspect ratio flukes of cetaceans. The swimming performance of the manatee is in accordance with its habits as an aquatic grazer that seasonally migrates over extended distances.

  7. Experimental Investigation and Analysis on Temperature Distribution in Water Pool of External Reactor Vessel Cooling System%压力容器外部冷却系统冷却水池温度场的实验研究及分析

    Institute of Scientific and Technical Information of China (English)

    李永春; 李飞; 程旭; 杨燕华

    2013-01-01

    压力容器外部非能动冷却系统采用换料水池作为冷却水源。在浮升力驱动的自然循环流动作用下,冷却水池内会逐渐出现热分层现象。本实验基于先进压水堆压力容器外部冷却系统模拟装置REPEC实验回路,通过测量实验系统内冷却水箱的温度场空间分布,对冷却水池的热分层与混合现象、发展规律和主要影响因素进行了实验分析。结果表明:实验水箱内温度场分布差异主要表现在高度方向;循环流量是影响热分层的重要参数,而水箱工质初始温度的影响非常微弱;针对本实验的无量纲一维瞬态温度场方程分析表明,水箱内温度场的发展规律主要受对流传热控制。%In the external reactor vessel passive cooling system ,the refueling water pool is used as the heat trap .Driven by buoyancy force ,thermal stratification phenomena occur spontaneously in the pool . T he thermal stratification and mixing phenomena , development process and main influencing factors in the refueling water pool with the REPEC test facility were studied .The experimental results show that the temperature distribution in the experimental water tank varies with height ,the circulation flow is one of the most important factors w hich influence the thermal stratification process in the water tank ,and the effect of initial water temperature is negligible .The analysis result of the 1-D non-dimensional transient temperature field equation show s that the development of the temperature field in the water tank is mainly controlled by convective heat transfer .

  8. Evolución del grado de implantación de programas de autocontrol en las piscinas de temporada en Araba/Álava Evolution of the implementation level of self-monitoring programmes for outdoor swimming pools in Araba/Álava Evolução do grau de implementação de programas de autocontrolo em piscinas sazonais em Araba/Álava

    Directory of Open Access Journals (Sweden)

    Arantza Armentia Álvarez

    2012-12-01

    Full Text Available El objetivo principal de este estudio ha sido realizar una valoración de la evolución del grado de implantación de programas de autocontrol en las piscinas descubiertas de Araba/Álava durante seis años (2006-2011. Para ello, en las inspecciones se cumplimentaron protocolos de comprobación basados en instrucciones técnicas, elaboradas para aunar criterios y valorar los diferentes planes del Programa de autocontrol (Estos planes son: 1. Tratamiento y vigilancia del agua; 2. Análisis del agua; 3. Limpieza y desinfección; 4. Seguridad, buenas prácticas e información al usuario; 5. Revisión y mantenimiento; 6. Control de plagas; 7. Proveedores, productos y servicios. Además, se usó una valoración consensuada de cada plan, con el fin de valorar objetivamente las instalaciones y la implantación del autocontrol.The main aim of this study was to carry out an assessment of the implementation level of the self-monitoring programme for outdoor swimming pools in Araba/Álava over a six-year period (2006-2011. For this purpose, inspections were carried out using checklists based on technical guidelines designed to unify criteria and assess the different plans within each self-monitoring programme, including the following: 1. Water Treatment and Monitoring; 2. Water analysis; 3. Cleansing and Disinfection; 4. Safety, Best Practices and User information; 5. Inspection and Maintenance; 6. Pest control; 7. Suppliers, Products and Services. Consensus-based assessments of each plan were also used to objectively evaluate the facilities and the level of implementation of the self-monitoring programme.Este estudo teve como objectivo principal realizar uma avaliação da evolução do grau de implementação de programas de auto controlo nas piscinas descobertas de Álava durante um período de seis anos (2006-2011. Nesse sentido, foram realizadas inspeções técnicas respeitando protocolos assentes em listas de verificação, destinados a unificar

  9. The Swim Pressure of Active Matter

    Science.gov (United States)

    Brady, John; Takatori, Sho; Yan, Wen

    2015-03-01

    Through their self-motion, active matter systems generate a unique ``swim pressure'' that is entirely athermal in origin. This new source for the active stress exists at all scales in both living and nonliving active systems, and also applies to larger organisms where inertia is important. Here we explain the origin of the swim stress and develop a simple thermodynamic model to study the self-assembly and phase separation in active soft matter. Our new swim stress perspective may help analyze and exploit a wide class of active soft matter, from swimming bacteria and catalytic nanobots, schools of fish and birds, and molecular motors that activate the cellular cytoskeleton.

  10. Reactor Neutrinos

    OpenAIRE

    Soo-Bong Kim; Thierry Lasserre; Yifang Wang

    2013-01-01

    We review the status and the results of reactor neutrino experiments. Short-baseline experiments have provided the measurement of the reactor neutrino spectrum, and their interest has been recently revived by the discovery of the reactor antineutrino anomaly, a discrepancy between the reactor neutrino flux state of the art prediction and the measurements at baselines shorter than one kilometer. Middle and long-baseline oscillation experiments at Daya Bay, Double Chooz, and RENO provided very ...

  11. The comparison of immobility time in experimental rat swimming models.

    Science.gov (United States)

    Calil, Caroline Morini; Marcondes, Fernanda Klein

    2006-09-27

    Rat swimming models have been used in studies about stress and depression. However, there is no consensus about interpreting immobility (helplessness or adaptation) in the literature. In the present study, immobility time, glucose and glycogen mobilization, corticosterone and the effect of desipramine and diazepam were investigated in two different models: swimming stress and the forced swimming test. Immobility time was lower in swimming stress than in the forced swimming test. Both swimming models increased corticosterone levels in comparison with control animal levels. Moreover, swimming stress induced higher corticosterone levels than the forced swimming test did [F(2,14)=59.52; pswimming stressswimming testswimming stress in comparison with the forced swimming test and control. The immobility time was recorded and measured in another group treated with desipramine and diazepam in two protocols: a single session of forced swimming test or swimming stress and two sessions (pre- and retest) of forced swimming model or swimming stress. Desipramine decreased the immobility time in the forced swimming test in both the single [F(2,25)=20.63; pswimming session, without changes in the swimming stress model. Diazepam increased the immobility time in the swimming stress but not in the forced swimming test during the single [F(2,26)=11.24; p=0.0003] and retest sessions [F(2,38)=4.17; p=0.02]. It was concluded that swimming stress and the forced swimming test induced different behavior, hormonal and metabolic responses and represented different situations to the animal.

  12. A Comparative Analysis of Swimming Styles in Competitive Swimming

    Science.gov (United States)

    von Loebbecke, Alfred; Mittal, Rajat; Gupta, Varun; Mark, Russell

    2007-11-01

    High-fidelity numerical simulations are being used to conduct a critical evaluation of swimming strokes in competitive swimming. We combine computational fluid dynamics (CFD), laser body scans, animation software, and video footage to develop accurate models of Olympic level swimmers and use these to examine contrasting styles of the dolphin kick as well as the arm strokes in back and front crawl stroke. In the dolphin kick, the focus is on examining the effects of Strouhal number, kick amplitude, frequency, and technique on thrust production. In the back stroke, we examine the performance of the so called ``flat stroke'' versus the ``deep catch,'' The most important aspect that separates the two major types of back stroke is the alignment or angle of attack of the palm during the stroke. In one style of front crawl arm stroke, there is greater elbow joint flexion, shoulder abduction and sculling whereas the other style consists of a straight arm pull dominated by simple shoulder flexion. Underlying the use of these two styles is the larger and more fundamental issue of the role of lift versus drag in thrust production and we use the current simulations to examine this issue in detail.

  13. Undulatory swimming in viscoelastic fluids

    CERN Document Server

    Shen, Xiaoning

    2011-01-01

    The effects of fluid elasticity on the swimming behavior of the nematode \\emph{Caenorhabditis elegans} are experimentally investigated by tracking the nematode's motion and measuring the corresponding velocity fields. We find that fluid elasticity hinders self-propulsion. Compared to Newtonian solutions, fluid elasticity leads to 35% slower propulsion speed. Furthermore, self-propulsion decreases as elastic stresses grow in magnitude in the fluid. This decrease in self-propulsion in viscoelastic fluids is related to the stretching of flexible molecules near hyperbolic points in the flow.

  14. Delayed Gamma Measurements in Different Nuclear Research Reactors Bringing Out the Importance of the Delayed Contribution in Gamma Flux Calculations

    Energy Technology Data Exchange (ETDEWEB)

    Fourmentel, D.; Radulovic, V.; Barbot, L.; Villard, J-F. [Alternative Energies and Atomic Energy Commission, CEA, DEN, DER, Instrumentation Sensors and Dosimetry Laboratory, Cadarache, 13108 Saint- Paul-Lez-Durance (France); Zerovnik, G.; Snoj, L. [Reactor Physics Department, Jozef Stefan Institute, SI-1000 Ljubljana (Slovenia); Tarchalski, M.; Pytel, K. [National Centre for Nuclear Research A. Soltana 7, 05-400 Swierk (Poland); Malouch, F. [Alternative Energies and Atomic Energy Commission - CEA, DEN, DM2S, Saclay, 91191, Gif-sur-Yvette (France)

    2015-07-01

    Neutron and gamma flux levels are key parameters in nuclear research reactors. In Material Testing Reactors, such as the future Jules Horowitz Reactor, under construction at the French Alternative Energies and Atomic Energy Commission (CEA Cadarache, France), the expected gamma flux levels are very high (nuclear heating is of the order of 20 W/g at 100 MWth). As gamma rays deposit their energy in the reactor structures and structural materials it is important to take them into account when designing irradiation devices. There are only a few sensors which allow measurements of the nuclear heating ; a recent development at the CEA Cadarache allows measurements of the gamma flux using a miniature ionization chamber (MIC). The measured MIC response is often compared with calculation using modern Monte Carlo (MC) neutron and photon transport codes, such as TRIPOLI-4 and MCNP6. In these calculations only the production of prompt gamma rays in the reactor is usually modelled thus neglecting the delayed gamma rays. Hence calculations and measurements are usually in better accordance for the neutron flux than for the gamma flux. In this paper we study the contribution of delayed gamma rays to the total MIC signal in order to estimate the systematic error in gamma flux MC calculations. In order to experimentally determine the delayed gamma flux contributions to the MIC response, we performed gamma flux measurements with CEA developed MIC at three different research reactors: the OSIRIS reactor (MTR - 70 MWth at CEA Saclay, France), the TRIGA MARK II reactor (TRIGA - 250 kWth at the Jozef Stefan Institute, Slovenia) and the MARIA reactor (MTR - 30 MWth at the National Center for Nuclear Research, Poland). In order to experimentally assess the delayed gamma flux contribution to the total gamma flux, several reactor shut down (scram) experiments were performed specifically for the purpose of the measurements. Results show that on average about 30 % of the MIC signal is due to

  15. CERN Electronics Pool presentations

    CERN Multimedia

    2011-01-01

    The CERN Electronics Pool has organised a series of presentations in collaboration with oscilloscope manufacturers. The last one will take place according to the schedule below.   Time will be available at the end of the presentation to discuss your personal needs. The Agilent presentation had to be postponed and will be organised later. -     Lecroy: Thursday, 24 November 2011, in 530-R-030, 14:00 to 16:30.

  16. Swim pressure: stress generation in active matter.

    Science.gov (United States)

    Takatori, S C; Yan, W; Brady, J F

    2014-07-11

    We discover a new contribution to the pressure (or stress) exerted by a suspension of self-propelled bodies. Through their self-motion, all active matter systems generate a unique swim pressure that is entirely athermal in origin. The origin of the swim pressure is based upon the notion that an active body would swim away in space unless confined by boundaries-this confinement pressure is precisely the swim pressure. Here we give the micromechanical basis for the swim stress and use this new perspective to study self-assembly and phase separation in active soft matter. The swim pressure gives rise to a nonequilibrium equation of state for active matter with pressure-volume phase diagrams that resemble a van der Waals loop from equilibrium gas-liquid coexistence. Theoretical predictions are corroborated by Brownian dynamics simulations. Our new swim stress perspective can help analyze and exploit a wide class of active soft matter, from swimming bacteria to catalytic nanobots to molecular motors that activate the cellular cytoskeleton.

  17. A method for determining critical swimming velocity.

    Science.gov (United States)

    Takahashi, S; Wakayoshi, K; Hayashi, A; Sakaguchi, Y; Kitagawa, K

    2009-02-01

    The purpose of this study was to determine whether the critical swimming velocity (Vcri) estimated by the swimming velocity for a distance of 300 m at maximal effort breaststroke reflects the maximal lactate steady state (MLSS). Twelve trained swimmers swam 50 m, 300 m and 2 000 m at maximal effort for determination of Vcri that averaged 1.167 +/- 0.045 m . sec (-1). Since Vcri was equivalent to 90.5 % of the mean swimming velocity over the distance of 300 m at maximal effort, the swimming velocity obtained by multiplying the swimming velocity for the distance of 300 m of each subject by 90.5 % was taken to be 100 % of the predicted critical swimming velocity (Vcri-pred). Then, in an MLSS test, the subjects were instructed to swim breaststroke 2 000 m (5 x 400 m) at three constant velocities (98 %, 100 %, and 102 % of Vcri-pred), interrupted by four short rest periods from 30 to 45 seconds for blood sampling and heart rate measurement. As a result, the blood lactate concentration at 100 % Vcri-pred showed a higher steady state than the slow velocity, but at high velocity did not show the steady state. In conclusion, we can accurately estimate the Vcri for breaststroke by a one-time 300-m maximal effort swimming test.

  18. Swim Pressure: Stress Generation in Active Matter

    Science.gov (United States)

    Takatori, S. C.; Yan, W.; Brady, J. F.

    2014-07-01

    We discover a new contribution to the pressure (or stress) exerted by a suspension of self-propelled bodies. Through their self-motion, all active matter systems generate a unique swim pressure that is entirely athermal in origin. The origin of the swim pressure is based upon the notion that an active body would swim away in space unless confined by boundaries—this confinement pressure is precisely the swim pressure. Here we give the micromechanical basis for the swim stress and use this new perspective to study self-assembly and phase separation in active soft matter. The swim pressure gives rise to a nonequilibrium equation of state for active matter with pressure-volume phase diagrams that resemble a van der Waals loop from equilibrium gas-liquid coexistence. Theoretical predictions are corroborated by Brownian dynamics simulations. Our new swim stress perspective can help analyze and exploit a wide class of active soft matter, from swimming bacteria to catalytic nanobots to molecular motors that activate the cellular cytoskeleton.

  19. Swimming and muscle structure in fish

    NARCIS (Netherlands)

    Spierts, I.L.Y.

    1999-01-01

    In this series of studies the relations between swimming behaviour of fish in general and extreme swimming responses in particular (called fast starts or escape responses) and the structure and ontogeny of the muscle system was investigated. Special attention was paid to relate functional difference

  20. How to swim with sharks: a primer.

    Science.gov (United States)

    Cousteau, Voltaire

    2011-08-01

    Swimming with the sharks is neither enjoyable nor exhilarating, and it is not an acknowledged sport. Some individuals, however, must swim by virtue of their occupation. If such an individual finds himself or herself in shark-infested waters, this article provides useful guidelines for survival.

  1. Swimming Motility Reduces Deposition to Silica Surfaces

    Energy Technology Data Exchange (ETDEWEB)

    Lu, Nanxi [Univ. of Illinois, Urbana-Champaign, IL (United States); Massoudieh, Arash [The Catholic Univ. of America, Washington, DC (United States); Liang, Xiaomeng [The Catholic Univ. of America, Washington, DC (United States); Hu, Dehong [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Kamai, Tamir [Agricultural Research Organization, Bet Dagan (Israel); Ginn, Timothy R. [Univ. of California, Davis, CA (United States); Zilles, Julie L. [Univ. of Illinois, Urbana-Champaign, IL (United States); Nguyen, Thanh H. [Univ. of Illinois, Urbana-Champaign, IL (United States)

    2015-01-01

    The role of swimming motility on bacterial transport and fate in porous media was evaluated. We present microscopic evidence showing that strong swimming motility reduces attachment of Azotobacter vinelandii cells to silica surfaces. Applying global and cluster statistical analyses to microscopic videos taken under non-flow conditions, wild type, flagellated A. vinelandii strain DJ showed strong swimming ability with an average speed of 13.1 μm/s, DJ77 showed impaired swimming averaged at 8.7 μm/s, and both the non-flagellated JZ52 and chemically treated DJ cells were non-motile. Quantitative analyses of trajectories observed at different distances above the collector of a radial stagnation point flow cell (RSPF) revealed that both swimming and non-swimming cells moved with the flow when at a distance of at least 20 μm from the collector surface. Near the surface, DJ cells showed both horizontal and vertical movement diverging them from reaching surfaces, while chemically treated DJ cells moved with the flow to reach surfaces, suggesting that strong swimming reduced attachment. In agreement with the RSPF results, the deposition rates obtained for two-dimensional multiple-collector micromodels were also lowest for DJ, while DJ77 and JZ52 showed similar values. Strong swimming specifically reduced deposition on the upstream surfaces of the micromodel collectors.

  2. Energetics of swimming of schooling fish

    DEFF Research Database (Denmark)

    Steffensen, John Fleng

    2012-01-01

    Soc for experimental Biol Annual Meeting - Salzburg 2012 John F. Steffensen (University of Copenhagen, Denmark) When a fish school swims through the water, every individual consumes a certain amount of oxygen, which means that less will be available for the trailing fish in the school. In 1967 Mc......Farland and Moss reported that the oxygen saturation decreased approximately 30% from the front to the rear of an approximately 150-m long school of mullets swimming in normoxic water. They also observed that the decline in oxygen saturation at the rear resulted in the school disintegrating into smaller separate...... schools. Oxygen consumption of swimming fish increases exponentially or as a power function with respect to swimming speed, and hence the decrease in oxygen saturation through the school is related to the swimming speed of the school. A model describing the oxygen saturation in a fish school from front...

  3. Enhanced active swimming in viscoelastic fluids

    CERN Document Server

    Riley, Emily E

    2014-01-01

    Swimming microorganisms often self propel in fluids with complex rheology. While past theoretical work indicates that fluid viscoelasticity should hinder their locomotion, recent experiments on waving swimmers suggest a possible non-Newtonian enhancement of locomotion. We suggest a physical mechanism, based on fluid-structure interaction, leading to swimming in a viscoelastic fluid at a higher speed than in a Newtonian one. Using Taylor's two-dimensional swimming sheet model, we solve for the shape of an active swimmer as a balance between the external fluid stresses, the internal driving moments, and the passive elastic resistance. We show that this dynamic balance leads to a generic transition from hindered rigid swimming to enhanced flexible locomotion. The results are physically interpreted as due to a viscoelastic suction increasing the swimming amplitude in a non-Newtonian fluid and overcoming viscoelastic damping.

  4. Effects of 4 weeks of creatine supplementation in junior swimmers on freestyle sprint and swim bench performance.

    Science.gov (United States)

    Dawson, Brian; Vladich, Todd; Blanksby, Brian A

    2002-11-01

    To determine whether 4 weeks of oral creatine (Cr) supplementation could enhance single freestyle sprint and swim bench performance in experienced competitive junior swimmers, 10 young men and 10 young women (x age = 16.4 +/- 1.8 years) participated in a 27-day supplementation period and pre- and posttesting sessions. In session 1 (presupplementation testing), subjects swam one 50-m freestyle and then (after approximately 5 minutes of active recovery) one 100-m freestyle at maximum speed. Blood lactate was measured before and 1 minute after each swim trial. Forty-eight hours later, height, mass, and the sum of 6 skinfolds were recorded, and a Biokinetic Swim Bench total work output test (2 x 30-second trials, with a 10-minute passive recovery in between) was undertaken. After the pretests were completed, participants were divided into 2 groups (n = 10, Cr; and n = 10, placebo) by means of matched pairs on the basis of gender and 50-m swim times. A Cr loading phase of 20 g x d(-1) for 5 days was then instituted, followed by a maintenance phase of 5 g x d(-1) for 22 days. Postsupplementation testing replicated the presupplementation tests. Four weeks of Cr supplementation did not influence single sprint performance in the pool or body mass and composition. However, 30-second swim bench total work scores for trial 1 and trial 2 increased after Cr (p swimmers, but it did enhance swim bench test performance.

  5. Steam-air mixture condensation in a subcooled water pool

    Science.gov (United States)

    Norman, Timothy Linhurst

    2007-12-01

    In any conceptual reactor design under postulated accidental conditions, one parameter that is considered as being highly ranked in determining the thermal-hydraulic conditions of the reactor safety components is the system pressure. To obtain a satisfactory prediction of steam partial pressure, within reasonable uncertainty in the gas space of a confined SP (suppression pool) bounded to the steam source of the break flow, one must establish a means by which local phenomena associated with steam direct contact condensation in the subcooled water pool can be fully addressed to predict the global component thermal response. For this purpose a scaled down, reduced pressure, suppression pool was designed and built to study condensation and mixing phenomena. The scaled test facility represented an idealized trapezoidal cross section, 1/10 sector of the SP with scaled height ratio of 1/4.5 and volume ratio of 1/400. The design and test conditions were based on a hierarchical scaling principle that preserves the transfer of mass, momentum, energy and condensation phenomena. Distributed thermocouples within the pool provided a means to quantify the pool thermal response. The test loop was not only instrumented with thermocouples for monitoring pool stratification but also with high speed photography for flow visualization from which to build a comprehensive database to identify the regions of the pool that were thermally stratified or mixed. Data were obtained for different pool initial subcooling and steam/air mixture flow rates. Dimensionless boundary maps were plotted from several experimental runs of pure steam injection to determine conditions when the pool transits from being homogeneously mixed to being thermally stratified. Steam-air mixture injection cases for single horizontal venting indicated that above a pool temperature of 40°C with airmass flow rates below 0.1 g/s the pool can attain thermal stratification. Models of a single phase liquid

  6. Preliminary Calculation on a Spent Fuel Pool Accident using GOTHIC

    Energy Technology Data Exchange (ETDEWEB)

    Park, Jaehwan; Choi, Yu Jung; Hong, Tae Hyub; Kim, Hyeong-Taek [KHNP-CRI, Daejeon (Korea, Republic of)

    2015-10-15

    The probability of an accident happening at the spent fuel pool was believed to be quite low until the 2011 Fukushima accident occurred. Notably, large amount of spent fuel are normally stored in the spent fuel pool for a long time compared to the amount of fuel in the reactor core and the total heat released from the spent fuel is high enough to boil the water of the spent fuel pool when the cooling system does not operate. In addition, the enrichment and the burnup of the fuel have both increased in the past decade and heat generation from the spent fuel thereby has also increased. The failure of the cooling system at the spent fuel pool (hereafter, a loss-of-cooling accident) is one of the principal hypothetical causes of an accident that could occur at the spent fuel pool. In this paper, the preliminary calculation of a loss-of-cooling accident was performed. In this paper, the preliminary calculation of a loss-of cooling accident was performed with GOTHIC. The calculation results show boiling away of water in the spent fuel pool due to the loss-of-cooling accident and similar thermal performance of the spent fuel pool with previous research results.

  7. 76 FR 47436 - Virginia Graeme Baker Pool and Spa Safety Act; Incorporation by Reference of Successor Standard

    Science.gov (United States)

    2011-08-05

    ... addition to multiple drains, UL 1563 requires that the suction fittings be installed with separation on... Consumer Product Safety Commission (``Commission,'' ``CPSC,'' or ``we'') finds the successor drain cover... prevent drain entrapment and child drowning in swimming pools and spas. The VGB Act requires that...

  8. Jules Horowitz Reactor, a new irradiation facility: Improving dosimetry for the future of nuclear experimentation

    Energy Technology Data Exchange (ETDEWEB)

    Gregoire, G.; Beretz, D.; Destouches, C. [CEA, DEN, DER/SPEX, F-13108 Saint-Paul-lez-Durance (France)

    2011-07-01

    Document available in abstract form only, full text of document follows: The Jules Horowitz Reactor (JHR) is an experimental reactor under construction at the French Nuclear Energy and Alternative Energies Commission (CEA) facility at Cadarache. It will achieve its first criticality by the end of 2014. Experiments that will be conducted at JHR will deal with fuel, cladding, and material behavior. The JHR will also produce medical radio-isotopes and doped silicon for the electronic industry. As a new irradiation facility, its instrumentation will benefit from recent improvements. Nuclear instrumentation will include reactor dosimetry, as it is a reference technique to determine neutron fluence in experimental devices or characterize irradiation locations. Reactor dosimetry has been improved with the progress of simulation tools and nuclear data, but at the same time the customer needs have increased: Experimental results must have reduced and assessed uncertainties. This is now a necessary condition to perform an experimental irradiation in a test reactor. Items improved, in the framework of a general upgrading of the dosimetry process based on uncertainty minimization, will include dosimeter, nuclear data, and modelling scheme. (authors)

  9. THE EFFECTS OF CREATINE LONG-TERM SUPPLEMENTATION ON MUSCLE MORPHOLOGY AND SWIMMING PERFORMANCE IN RATS

    Directory of Open Access Journals (Sweden)

    Sena Erdal

    2009-12-01

    Full Text Available Creatine (Cr has been shown to increase the total muscle mass. The purpose of this study was to investigate the effect of Cr supplementation on muscle morphology and swimming performance, using an animal model. Each rat was subjected to exercise 15-minute period daily for the 12 weeks. The rats were randomly divided into four groups: no Cr supplementation (CON, no Cr supplementation and incomplete food intake (lacking lysine and methionine in diet for rats (INCO, Cr supplementation 1 g·kg-1·day-1 (CREAT-I and Cr supplementation 2 g·kg-1·day-1 (CREAT-II. Three months later, all groups adult rats exercised in swimming pool chambers. Swimming time was recorded as minute for each rat. Following swimming performance period, the animals were killed by cervical dislocation and the gastrocnemius and diaphragm muscles were dissected. Serial slices of 5-7 μm were allocated paraffin wax and histochemical staining procedure of cross-sections was carried out with heamatoxylin-eosin technics. All groups gained body weight at the end of 12 weeks but there was no statistical difference among them. Swimming time values were statistical difference between CREAT-II and CON group as well as between CREAT-I and CON group (p < 0.05. In the INCO group was determined increased connective tissue cell of the muscle sample. In contrast, in the CREAT-I and CREAT-II group, the basic histological changes were large-scale muscle fibers and hypertrophic muscle cells. These results suggest that long-term creatine supplementation increased the number of muscle fibers and enhanced endurance swimming performance in rats

  10. Krill (Meganyctiphanes norvegica) swim faster at night

    KAUST Repository

    Klevjer, Thor A.

    2011-05-01

    Krill are key members in marine food webs, and measurement of swimming speed is vital to assess their bioenergetic budgets, feeding, and encounters with predators. We document a consistent and marked diel signal in swimming speed of krill in their natural habitat that is not related to diel vertical migration. The results were obtained using a bottom-mounted, upward-looking echo sounder at 150-m depth in the Oslofjord, Norway, spanning 5 months from late autumn to spring at a temporal resolution of ~1–2 records s−1. Swimming speed was assessed using acoustic target tracking of individual krill. At the start of the registration period, both daytime and nocturnal average swimming speeds of Meganyctiphanes norvegica were ~ 3.5 cm s−1 (~ 1 body lengths ([bl] s−1) in waters with oxygen concentrations of ~ 15–20% O2 saturation. Following intrusion of more oxygenated water, nocturnal average swimming speeds increased to ~ 10 cm s−1 (~ 3 bl s−1), i.e., more than double that of daytime swimming speeds in the same period. We hypothesize that krill activity during the first period was limited by oxygen, and the enhanced swimming at night subsequent to the water renewal is due to increased feeding activity under lessened danger of predation in darkness.

  11. Swimming behavior of selected species of Archaea.

    Science.gov (United States)

    Herzog, Bastian; Wirth, Reinhard

    2012-03-01

    The swimming behavior of Bacteria has been studied extensively, at least for some species like Escherichia coli. In contrast, almost no data have been published for Archaea on this topic. In a systematic study we asked how the archaeal model organisms Halobacterium salinarum, Methanococcus voltae, Methanococcus maripaludis, Methanocaldococcus jannaschii, Methanocaldococcus villosus, Pyrococcus furiosus, and Sulfolobus acidocaldarius swim and which swimming behavior they exhibit. The two Euryarchaeota M. jannaschii and M. villosus were found to be, by far, the fastest organisms reported up to now, if speed is measured in bodies per second (bps). Their swimming speeds, at close to 400 and 500 bps, are much higher than the speed of the bacterium E. coli or of a very fast animal, like the cheetah, each with a speed of ca. 20 bps. In addition, we observed that two different swimming modes are used by some Archaea. They either swim very rapidly, in a more or less straight line, or they exhibit a slower kind of zigzag swimming behavior if cells are in close proximity to the surface of the glass capillary used for observation. We argue that such a "relocate-and-seek" behavior enables the organisms to stay in their natural habitat.

  12. The Productive Ligurian Pool

    CERN Document Server

    Casella, E; Couvelard, X; Caldeira, R M A

    2011-01-01

    In contrast with the behavior of the eddies in the open-ocean, the sub-mesoscale eddies generated in the constricted Ligurian Basin (NW Mediterranean), are unproductive but their combined effect, arranged in a rim-like fashion, contributes to the containment of a Productive Ligurian Pool (PLP). Data de- rived from MODIS satellite sensor showed persistent higher chlorophyll con- centrations in the centre of the basin, concurrent with high EKE values in its surroundings, derived from AVISO altimetry merged products. This sug- gested that this 'productive pool' is maintained by the intense (sub)mesoscale eddy activity in the rim. Numerical realistic experiments, using a Regional Ocean Model System, forced by MERCATOR and by a high-resolution COSMO- l7 atmospheric model, also showed that most of the sub-mesoscale eddies, during 2009 and 2010, are concentrated in the rim surrounding the basin, contributing to the formation of a basin-scale cyclonic gyre. We hypothesized that the interaction between eddies in the r...

  13. Swimming of the Honey Bees

    Science.gov (United States)

    Roh, Chris; Gharib, Morteza

    2016-11-01

    When the weather gets hot, nursing honey bees nudge foragers to collect water for thermoregulation of their hive. While on their mission to collect water, foragers sometimes get trapped on the water surface, forced to interact with a different fluid environment. In this study, we present the survival strategy of the honey bees at the air-water interface. A high-speed videography and shadowgraph were used to record the honey bees swimming. A unique thrust mechanism through rapid vibration of their wings at 60 to 150 Hz was observed. This material is based upon work supported by the National Science Foundation under Grant No. CBET-1511414; additional support by the National Science Foundation Graduate Research Fellowship under Grant No. DGE-1144469.

  14. The critical velocity in swimming.

    Science.gov (United States)

    di Prampero, Pietro E; Dekerle, Jeanne; Capelli, Carlo; Zamparo, Paola

    2008-01-01

    In supra-maximal exercise to exhaustion, the critical velocity (cv) is conventionally calculated from the slope of the distance (d) versus time (t) relationship: d = I + St. I is assumed to be the distance covered at the expense of the anaerobic capacity, S the speed maintained on the basis of the subject's maximal O(2) uptake (VO2max) This approach is based on two assumptions: (1) the energy cost of locomotion per unit distance (C) is constant and (2) VO2max is attained at the onset of exercise. Here we show that cv and the anaerobic distance (d (anaer)) can be calculated also in swimming, where C increases with the velocity, provided that VO2max its on-response, and the C versus v relationship are known. d (anaer) and cv were calculated from published data on maximal swims for the four strokes over 45.7, 91.4 and 182.9 m, on 20 elite male swimmers (18.9 +/- 0.9 years, 75.9 +/- 6.4 kg), whose VO2max and C versus speed relationship were determined, and compared to I and S obtained from the conventional approach. cv was lower than S (4, 16, 7 and 11% in butterfly, backstroke, breaststroke and front crawl) and I (=11.6 m on average in the four strokes) was lower than d (anaer). The latter increased with the distance: average, for all strokes: 38.1, 60.6 and 81.3 m over 45.7, 91.4 and 182.9 m. It is concluded that the d versus t relationship should be utilised with some caution when evaluating performance in swimmers.

  15. SWIM EVERYDAY TO KEEP DEMENTIA AWAY

    Directory of Open Access Journals (Sweden)

    Nirmal Singh

    2005-03-01

    Full Text Available A sound mind resides in a sound body. Many individuals with an active lifestyle show sharp mental skills at an advanced age. Regular exercise has been shown to exert numerous beneficial effects on brawn as well as brain. The present study was undertaken to evaluate the influence of swimming on memory of rodents. A specially designed hexagonal water maze was used for the swimming exposures of animals. The learning and memory parameters were measured using exteroceptive behavioral models such as Elevated plus-maze, Hebb-Williams maze and Passive avoidance apparatus. The rodents (rats and mice were divided into twelve groups. The swimming exposure to the rodents was for 10- minute period during each session and there were two swimming exposures on each day. Rats and mice were subjected to swimming for -15 and -30 consecutive days. Control group animals were not subjected to swimming during above period. The learning index and memory score of all the animals was recorded on 1st, 2nd, 15th, 16th, 30th and 31st day employing above exteroceptive models. It was observed that rodents that underwent swimming regularly for 30- days showed sharp memories, when tested on above behavioral models whereas, control group animals showed decline in memory scores. Those animals, which underwent swimming for 15- days only showed good memory on 16th day, which however, declined after 30-days. These results emphasize the role of regular physical exercise particularly swimming in the maintenance and promotion of brain functions. The underlying physiological mechanism for improvement of memory appears to be the result of enhanced neurogenesis.

  16. 76 FR 58401 - Safety Zone; Swim Around Charleston, Charleston, SC

    Science.gov (United States)

    2011-09-21

    ... Zone; Swim Around Charleston, Charleston, SC in the Federal Register (76 FR 38586). We received no... SECURITY Coast Guard 33 CFR Part 165 RIN 1625-AA00 Safety Zone; Swim Around Charleston, Charleston, SC... temporary moving safety zone during the Swim Around Charleston, a swimming race occurring on waters of...

  17. Swimming and feeding of mixotrophic biflagellates

    DEFF Research Database (Denmark)

    Dölger, Julia; Nielsen, Lasse Tor; Kiørboe, Thomas

    2017-01-01

    Many unicellular flagellates are mixotrophic and access resources through both photosynthesis and prey capture. Their fitness depends on those processes as well as on swimming and predator avoidance. How does the flagellar arrangement and beat pattern of the flagellate affect swimming speed...... with variable position next to a no-slip sphere. Utilizing the observations and the model we find that puller force arrangements favour feeding, whereas equatorial force arrangements favour fast and quiet swimming. We determine the capture rates of both passive and motile prey, and we show that the flow...

  18. Quiet swimming at low Reynolds number

    DEFF Research Database (Denmark)

    Andersen, Anders Peter; Wadhwa, Navish; Kiørboe, Thomas

    2015-01-01

    The stresslet provides a simple model of the flow created by a small, freely swimming and neutrally buoyant aquatic organism and shows that the far field fluid disturbance created by such an organism in general decays as one over distance squared. Here we discuss a quieter swimming mode......-Stokeslet model of a swimming organism which uses breast stroke type kinematics is an example of such a quiet swimmer. We show that the fluid disturbance in both the near field and the far field is significantly reduced by appropriately arranging the propulsion apparatus, and we find that the far field power laws...

  19. Analysis of the MEX-15 multipurpose reactor using SRAC code system

    Energy Technology Data Exchange (ETDEWEB)

    Alonso V, G. [ININ, 52045 Ocoyoacac, Estado de Mexico (Mexico)

    1992-12-15

    The MEX-15 is a conceptual design of a Multipurpose Reactor with thermal power of 15 MW and this reactor is pool type with fuel plates U{sub 3}0{sub 8}-Al of low enrichment uranium. This report presents the static calculation for the MEX-15 reactor using SRAC code system and was developed under the collaboration agreement between ININ-JAERI in Research Reactor Technology Development Division of Department of Research Reactor in Tokai Research Establishment. (Author)

  20. Measurement of hydrodynamic force generation by swimming dolphins using bubble DPIV.

    Science.gov (United States)

    Fish, Frank E; Legac, Paul; Williams, Terrie M; Wei, Timothy

    2014-01-15

    Attempts to measure the propulsive forces produced by swimming dolphins have been limited. Previous uses of computational hydrodynamic models and gliding experiments have provided estimates of thrust production by dolphins, but these were indirect tests that relied on various assumptions. The thrust produced by two actively swimming bottlenose dolphins (Tursiops truncatus) was directly measured using digital particle image velocimetry (DPIV). For dolphins swimming in a large outdoor pool, the DPIV method used illuminated microbubbles that were generated in a narrow sheet from a finely porous hose and a compressed air source. The movement of the bubbles was tracked with a high-speed video camera. Dolphins swam at speeds of 0.7 to 3.4 m s(-1) within the bubble sheet oriented along the midsagittal plane of the animal. The wake of the dolphin was visualized as the microbubbles were displaced because of the action of the propulsive flukes and jet flow. The oscillations of the dolphin flukes were shown to generate strong vortices in the wake. Thrust production was measured from the vortex strength through the Kutta-Joukowski theorem of aerodynamics. The dolphins generated up to 700 N during small amplitude swimming and up to 1468 N during large amplitude starts. The results of this study demonstrated that bubble DPIV can be used effectively to measure the thrust produced by large-bodied dolphins.

  1. A Single-Unit Design Structure and Gender Differences in the Swimming World Championships

    Science.gov (United States)

    Pushkar, Svetlana; Issurin, Vladimir B.; Verbitsky, Oleg

    2014-01-01

    Four 50 meter male/female finals - the freestyle, butterfly, breaststroke, and backstroke - swum during individual events at the Swimming World Championships (SWCs) can be defined in four clusters. The aim of the present study was to use a single-unit design structure, in which the swimmer was defined at only one scale, to evaluate gender differences in start reaction times among elite swimmers in 50 m events. The top six male and female swimmers in the finals of four swimming stroke final events in six SWCs were analyzed. An unpaired t-test was used. The p-values were evaluated using Neo-Fisherian significance assessments (Hurlbert and Lombardi, 2012). For the freestyle, gender differences in the start reaction times were positively identified for five of the six SWCs. For the backstroke, gender differences in the start reaction times could be dismissed for five of the six SWCs. For both the butterfly and breaststroke, gender differences in the start reaction times yielded inconsistent statistical differences. Pooling all swimmers together (df = 286) showed that an overall gender difference in the start reaction times could be positively identified: p = 0.00004. The contrast between the gender differences in start reaction times between the freestyle and backstroke may be associated with different types of gender adaptations to swimming performances. When the natural groupings of swimming stroke final events were ignored, sacrificial pseudoreplication occurred, which may lead to erroneous statistical differences. PMID:25414754

  2. A Single-Unit Design Structure and Gender Differences in the Swimming World Championships

    Directory of Open Access Journals (Sweden)

    Pushkar Svetlana

    2014-10-01

    Full Text Available Four 50 meter male/female finals - the freestyle, butterfly, breaststroke, and backstroke - swum during individual events at the Swimming World Championships (SWCs can be defined in four clusters. The aim of the present study was to use a single-unit design structure, in which the swimmer was defined at only one scale, to evaluate gender differences in start reaction times among elite swimmers in 50 m events. The top six male and female swimmers in the finals of four swimming stroke final events in six SWCs were analyzed. An unpaired t-test was used. The p-values were evaluated using Neo-Fisherian significance assessments (Hurlbert and Lombardi, 2012. For the freestyle, gender differences in the start reaction times were positively identified for five of the six SWCs. For the backstroke, gender differences in the start reaction times could be dismissed for five of the six SWCs. For both the butterfly and breaststroke, gender differences in the start reaction times yielded inconsistent statistical differences. Pooling all swimmers together (df = 286 showed that an overall gender difference in the start reaction times could be positively identified: p = 0.00004. The contrast between the gender differences in start reaction times between the freestyle and backstroke may be associated with different types of gender adaptations to swimming performances. When the natural groupings of swimming stroke final events were ignored, sacrificial pseudoreplication occurred, which may lead to erroneous statistical differences

  3. Synaptic vesicle pools: an update

    Directory of Open Access Journals (Sweden)

    Annette Denker

    2010-10-01

    Full Text Available During the last few decades synaptic vesicles have been assigned to a variety of functional and morphological classes or pools. We have argued in the past (Rizzoli SO and Betz WJ, 2005, Synaptic vesicle pools, Nat. Rev. Neurosci. 6, 57-69 that synaptic activity in several preparations is accounted for by the function of three vesicle pools: the readily releasable pool (docked at active zones and ready to go upon stimulation, the recycling pool (scattered throughout the nerve terminals and recycling upon moderate stimulation, and finally the reserve pool (occupying most of the vesicle clusters and only recycling upon strong stimulation. We discuss here the advancements in the vesicle pool field which took place in the ensuing years, focusing on the behavior of different pools under both strong stimulation and physiological activity. Several new findings have enhanced the three-pool model, with, for example, the disparity between recycling and reserve vesicles being underlined by the observation that the former are mobile, while the latter are fixed. Finally, a number of altogether new concepts have also evolved such as the current controversy on the identity of the spontaneously recycling vesicle pool.

  4. Multifunctional reactors

    NARCIS (Netherlands)

    Westerterp, K.R.

    1992-01-01

    Multifunctional reactors are single pieces of equipment in which, besides the reaction, other functions are carried out simultaneously. The other functions can be a heat, mass or momentum transfer operation and even another reaction. Multifunctional reactors are not new, but they have received much

  5. Muscle dynamics in fish during steady swimming

    DEFF Research Database (Denmark)

    Shadwick, RE; Steffensen, JF; Katz, SL

    1998-01-01

    SYNOPSIS. Recent research in fish locomotion has been dominated by an interest in the dynamic mechanical properties of the swimming musculature. Prior observations have indicated that waves of muscle activation travel along the body of an undulating fish faster than the resulting waves of muscular...... position in swimming fish. Quantification of muscle contractile properties in cyclic contractions relies on in vitro experiments using strain and activation data collected in vivo. In this paper we discuss the relation between these parameters and body kinematics. Using videoradiographic data from swimming...... constant cross-section of red muscle along much of the body suggests that positive power for swimming is generated fairly uniformly along the length of the fish....

  6. Optimal Strouhal number for swimming animals

    CERN Document Server

    Eloy, Christophe

    2011-01-01

    To evaluate the swimming performances of aquatic animals, an important dimensionless quantity is the Strouhal number, St = fA/U, with f the tail-beat frequency, A the peak-to-peak tail amplitude, and U the swimming velocity. Experiments with flapping foils have exhibited maximum propulsive efficiency in the interval 0.25 < St < 0.35 and it has been argued that animals likely evolved to swim in the same narrow interval. Using Lighthill's elongated-body theory to address undulatory propulsion, it is demonstrated here that the optimal Strouhal number increases from 0.15 to 0.8 for animals spanning from the largest cetaceans to the smallest tadpoles. To assess the validity of this model, the swimming kinematics of 53 different species of aquatic animals have been compiled from the literature and it shows that their Strouhal numbers are consistently near the predicted optimum.

  7. Can phoretic particles swim in two dimensions?

    CERN Document Server

    Sondak, David; Heng, Siyu; Vinsonhaler, Rebecca; Lauga, Eric; Thiffeault, Jean-Luc

    2016-01-01

    Artificial phoretic particles swim using self-generated gradients in chemical species (self-diffusiophoresis) or charges and currents (self-electrophoresis). These particles can be used to study the physics of collective motion in active matter and might have promising applications in bioengineering. In the case of self-diffusiophoresis, the classical physical model relies on a steady solution of the diffusion equation, from which chemical gradients, phoretic flows and ultimately the swimming velocity, may be derived. Motivated by disk-shaped particles in thin films and under confinement, we examine the extension to two dimensions. Because the two-dimensional diffusion equation lacks a steady state with the correct boundary conditions, Laplace transforms must be used to study the long-time behavior of the problem and determine the swimming velocity. For fixed chemical fluxes on the particle surface, we find that the swimming velocity ultimately always decays logarithmically in time. In the case of finite Pecl...

  8. Muscle function and swimming in sharks.

    Science.gov (United States)

    Shadwick, R E; Goldbogen, J A

    2012-04-01

    The locomotor system in sharks has been investigated for many decades, starting with the earliest kinematic studies by Sir James Gray in the 1930s. Early work on axial muscle anatomy also included sharks, and the first demonstration of the functional significance of red and white muscle fibre types was made on spinal preparations in sharks. Nevertheless, studies on teleosts dominate the literature on fish swimming. The purpose of this article is to review the current knowledge of muscle function and swimming in sharks, by considering their morphological features related to swimming, the anatomy and physiology of the axial musculature, kinematics and muscle dynamics, and special features of warm-bodied lamnids. In addition, new data are presented on muscle activation in fast-starts. Finally, recent developments in tracking technology that provide insights into shark swimming performance in their natural environment are highlighted.

  9. Large pool LMFBR design. Final report. Volume 1

    Energy Technology Data Exchange (ETDEWEB)

    Wett, J. F.; Churchill, J. R.

    1979-03-01

    The design effort reported is an extension on past design effort and continuous concentration on those parts of the nuclear island unique to a commercial size pool type LMFBR. In particular, the work covers the reactor vessel, deck, rotating plugs, upper and lower internals, internal plenum separator system, IHX, pumps, cold traps, intermediate system layout, containment/confinement system, plot plan, and residual heat removal systems. Preliminary thermal, hydraulic, stress, and system analyses are also presented.

  10. Brazilian multipurpose reactor

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2014-07-01

    The Brazilian Multipurpose Reactor (RMB) Project is an action of the Federal Government, through the Ministry of Science Technology and Innovation (MCTI) and has its execution under the responsibility of the Brazilian National Nuclear Energy Commission (CNEN). Within the CNEN, the project is coordinated by the Research and Development Directorate (DPD) and developed through research units of this board: Institute of Nuclear Energy Research (IPEN); Nuclear Engineering Institute (IEN); Centre for Development of Nuclear Technology (CDTN); Regional Center of Nuclear Sciences (CRCN-NE); and Institute of Radiation Protection and Dosimetry (IRD). The Navy Technological Center in Sao Paulo (CTMSP) and also the participation of other research centers, universities, laboratories and companies in the nuclear sector are important and strategic partnerships. The conceptual design and the safety analysis of the reactor and main facilities, related to nuclear and environmental licensing, are performed by technicians of the research units of DPD / CNEN. The basic design was contracted to engineering companies as INTERTHECNE from Brazil and INVAP from Argentine. The research units from DPD/CNEN are also responsible for the design verification on all engineering documents developed by the contracted companies. The construction and installation should be performed by specific national companies and international partnerships. The Nuclear Reactor RMB will be a open pool type reactor with maximum power of 30 MW and have the OPAL nuclear reactor of 20 MW, built in Australia and designed by INVAP, as reference. The RMB reactor core will have a 5x5 configuration, consisting of 23 elements fuels (EC) of U{sub 3}Si{sub 2} dispersion-type Al having a density of up to 3.5 gU/cm{sup 3} and enrichment of 19.75% by weight of {sup 23{sup 5}}U. Two positions will be available in the core for materials irradiation devices. The main objectives of the RMB Reactor and the other nuclear and radioactive

  11. Morphology of drying blood pools

    Science.gov (United States)

    Laan, Nick; Smith, Fiona; Nicloux, Celine; Brutin, David; D-Blood project Collaboration

    2016-11-01

    Often blood pools are found on crime scenes providing information concerning the events and sequence of events that took place on the scene. However, there is a lack of knowledge concerning the drying dynamics of blood pools. This study focuses on the drying process of blood pools to determine what relevant information can be obtained for the forensic application. We recorded the drying process of blood pools with a camera and measured the weight. We found that the drying process can be separated into five different: coagulation, gelation, rim desiccation, centre desiccation, and final desiccation. Moreover, we found that the weight of the blood pool diminishes similarly and in a reproducible way for blood pools created in various conditions. In addition, we verify that the size of the blood pools is directly related to its volume and the wettability of the surface. Our study clearly shows that blood pools dry in a reproducible fashion. This preliminary work highlights the difficult task that represents blood pool analysis in forensic investigations, and how internal and external parameters influence its dynamics. We conclude that understanding the drying process dynamics would be advancement in timeline reconstitution of events. ANR funded project: D-Blood Project.

  12. Jules Horowitz Reactor: Organisation for the Preparation of the Commissioning Phase and Normal Operation

    Energy Technology Data Exchange (ETDEWEB)

    Estrade, J.; Fabre, J. L.; Marcille, O. [French Alternative Energies end Atomic Energy Commission, Provence (France)

    2013-07-01

    The Jules Horowitz Reactor (JHR) is a new modern Material Testing Reactor (MTR) currently under construction at CEA Cadarache research centre in the south of France. It will be a major research facility in support to the development and the qualification of materials and fuels under irradiation with sizes and environment conditions relevant for nuclear power plants in order to optimise and demonstrate safe operations of existing power reactors as well as to support future reactors design. It will represent also an important research infrastructure for scientific studies dealing with material and fuel behaviour under irradiation. The JHR will contribute also to secure the production of radioisotope for medical application. This is a key public health stake. The construction of JHR which started in 2007 is going-on with target of commissioning by the end of 2017. The design of the reactor provides modern experimental capacity in support to R and D programs for the nuclear energy for the next 60 years. In parallel to the facility construction, the preparation of the future staff and of the organisation to operate the reactor safely, reliably and efficiently is an important issue. In this framework, many actions are in progress to elaborate: Ο the staffing and the organisational structure for the commissioning test phases and also for normal operation, Ο the documentation in support to the reactor operation (safety analysis report, general operating rules, procedures, instructions, ···), Ο the maintenance, in service and periodic test programs, Ο staff training programs by using dedicated facilities (simulator, ···) Ο commissioning test programs for ensuring that the layout of systems and subcomponents is completed in accordance with the design requirements, the specification performances and the safety criteria. These commissioning tests will also be helpful for transferring the knowledge on the installed systems to the operating group. This paper gives the

  13. Disinfection by-products and microbial contamination in the treatment of pool water with granular activated carbon.

    Science.gov (United States)

    Uhl, W; Hartmann, C

    2005-01-01

    For swimming pools, it is generally agreed that free chlorine levels have to be maintained to guarantee adequate disinfection. Recommended free chlorine levels can vary between 0.3 and 0.6 mg/L in Germany and up to 3 mg/L in other countries. Bathers introduce considerable amounts of organic matter, mainly in the form of such as urine and sweat, into the pool water. As a consequence, disinfection byproducts (DBPs) are formed. Regulations in Germany recommend levels of combined chlorine of less than 0.2 mg/L and levels of trihalomethanes (THMs) of less than 20 microg/L. Haloacetic acids (HAAs), haloacetonitriles (HANs), chloropicrin and chloral hydrate are also detected in considerable amounts. However, these compounds are not regulated yet. Swimming pool staff and swimmers, especially athletes, are primarily exposed to these byproducts by inhalation and/or dermal uptake. In Germany, new regulations for swimming pool water treatment generally require the use of activated carbon. In this project, three different types of granular activated carbon (GAC) (one standard GAC, two catalytic GACs) are compared for their long time behaviour in pool water treatment. In a pilot plant operated with real swimming pool water, production and removal of disinfection byproducts (THMs, HAAs, AOXs), of biodegradable substances (AOC), of bacteria (Pseudomonas aeruginosa, Legionella, coliforms, HPC) as well as the removal of chlorine and chloramines are monitored as function of GAC bed depth. Combined chlorine penetrates deeper in the filter bed than free chlorine does. However, both, free and combined chlorine removal efficiencies decrease over the time of filter operation. The decreases of removal efficiencies are also observed for parameters such as dissolved organic carbon, spectral absorption coefficient, adsorbable organic carbon and most of the disinfection byproducts. However, THMs, especially chloroform are produced in the filter bed. The GAC beds were contaminated microbially

  14. Are there limits to swimming world records?

    Science.gov (United States)

    Nevill, A M; Whyte, G P; Holder, R L; Peyrebrune, M

    2007-12-01

    The purpose of this article was to investigate whether swimming world records are beginning to plateau and whether the inequality between men and women's swimming performances is narrowing, similar to that observed in running world records. A flattened "S-shaped curve" logistic curve is fitted to 100-m, 200-m, and 400-m front-crawl world-record swimming speeds for men and women from 1 May 1957 to the present time, using the non-linear least-squares regression. The inequality between men and women's world records is also assessed using the ratio, Women's/Men's world record speeds. The results confirm that men and women's front-crawl swimming world-record speeds are plateauing and the ratio between women's and men's world records has remained stable at approximately 0.9. In conclusion, the logistic curves provide evidence that swimming world-record speeds experienced a period of "accelerated" growth/improvements during the 1960 - 1970s, but are now beginning to plateau. The period of acceleration corresponded with numerous advances in science and technology but also coincided with the anecdotal evidence for institutionalised doping. Also noteworthy, however, is the remarkably consistency in the women's/men's world record ratio, circa 0.9, similar to those observed in middle and long distance running performances. These finding supports the notion that a 10 % gender inequality exists for both swimming and running.

  15. Swimming Vorticella convallaria in various confined geometries

    Science.gov (United States)

    Sotelo, Luz; Lee, Donghee; Jung, Sunghwan; Ryu, Sangjin

    2014-11-01

    Vorticella convallaria is a stalked ciliate observed in the sessile form (trophont) or swimming form (telotroch). Trophonts are mainly composed of an inverted bell-shaped cell body generating vortical feeding currents, and a slender stalk attaching the cell body to a substrate. If the surrounding environment is no longer suitable, the trophont transforms into a telotroch by elongating its cell body into a cylindrical shape, resorbing its oral cilia and producing an aboral cilia wreath. After a series of contractions, the telotroch will completely detach from the stalk and swim away to find a better location. While sessile Vorticella has been widely studied because of its stalk contraction and usefulness in waste treatment, Vorticella's swimming has not yet been characterized. The purpose of this study is to describe V. convallaria's swimming modes, both in its trophont and telotroch forms, in different confined geometries. Using video microscopy, we observed Vorticellae swimming in semi-infinite field, in Hele-Shaw configurations, and in capillary tubes. Based on measured swimming displacement and velocity, we investigated how V. convallaria's mobility was affected by the geometry constrictions. We acknolwedge support from the First Award grant of Nebraska EPSCoR.

  16. Limit cycle dynamics in swimming systems

    Science.gov (United States)

    Finkel, Cyndee; von Ellenrieder, Karl

    2013-11-01

    An experimental apparatus was constructed to model basic features expected in the flow about a freely swimming fish. A D-shaped cylinder is used to represent the body and an oscillating foil, the tail. The swimming system is suspended in a constant freestream flow. A closed loop PI controller is used to maintain a set point, stream-wise location. The system is released from multiple downstream and upstream locations and permitted to swim to the set point. The Strouhal number measured when the swimming system achieves a constant forward swimming speed is compared to values observed in nature. The results suggest that self-regulation passively selects the Strouhal number and that no other external sensory input is necessary for this to happen. This self-regulation is a result of a limit cycle process that stems from nonlinear periodic oscillations. Phase plane analyses are used to examine the synchronous conditions due to the coupling of the foil and wake vortices. It is shown that the phase locking indices depend on the Strouhal number and approach a frequency locking ratio of about 0 . 5 . The results suggest that Strouhal number selection in steady forward natural swimming is the result of a limit cycle process and not actively controlled by an organism.

  17. Reactor vessel

    OpenAIRE

    Makkee, M.; Kapteijn, F.; Moulijn, J.A

    1999-01-01

    A reactor vessel (1) comprises a reactor body (2) through which channels (3) are provided whose surface comprises longitudinal inwardly directed parts (4) and is provided with a catalyst (6), as well as buffer bodies (8, 12) connected to the channels (3) on both sides of the reactor body (2) and comprising connections for supplying (9, 10, 11) and discharging (13, 14, 15) via the channels (3) gases and/or liquids entering into a reaction with each other and substances formed upon this reactio...

  18. After swimming one goes on the ice. Multifunctional complex of sports and leisure uses energetic synergies; Nach dem Schwimmen geht's aufs Eis. Multifunktionaler Sport- und Freizeitkomplex nutzt energetische Synergien

    Energy Technology Data Exchange (ETDEWEB)

    Jaeger, Frank Peter [Redaktionbuero Archikontext, Berlin (Germany); Vonseelen, Tanja

    2012-11-01

    In Lentpark (Cologne, Federal Republic of Germany) skating and swimming are combined in one building - an unusual combination of use with tradition in Cologne. Recently the bureau Schulitz Architecture + Technology (Braunschweig, Federal Republic of Germany) designed the completed new building of the ice ring and swimming hall. The new building develops the energetic synergies of the coexistence of ice preparation and water heating. The new building was commissioned by KoelnBaeder GmbH (Cologne, Federal Republic of Germany) and is a unique of modern skating arena with spectacular ice overhead way, swimming pool and sauna in Europe.

  19. NUCLEAR REACTOR

    Science.gov (United States)

    Miller, H.I.; Smith, R.C.

    1958-01-21

    This patent relates to nuclear reactors of the type which use a liquid fuel, such as a solution of uranyl sulfate in ordinary water which acts as the moderator. The reactor is comprised of a spherical vessel having a diameter of about 12 inches substantially surrounded by a reflector of beryllium oxide. Conventionnl control rods and safety rods are operated in slots in the reflector outside the vessel to control the operation of the reactor. An additional means for increasing the safety factor of the reactor by raising the ratio of delayed neutrons to prompt neutrons, is provided and consists of a soluble sulfate salt of beryllium dissolved in the liquid fuel in the proper proportion to obtain the result desired.

  20. Reactor Neutrinos

    Directory of Open Access Journals (Sweden)

    Soo-Bong Kim

    2013-01-01

    Full Text Available We review the status and the results of reactor neutrino experiments. Short-baseline experiments have provided the measurement of the reactor neutrino spectrum, and their interest has been recently revived by the discovery of the reactor antineutrino anomaly, a discrepancy between the reactor neutrino flux state of the art prediction and the measurements at baselines shorter than one kilometer. Middle and long-baseline oscillation experiments at Daya Bay, Double Chooz, and RENO provided very recently the most precise determination of the neutrino mixing angle θ13. This paper provides an overview of the upcoming experiments and of the projects under development, including the determination of the neutrino mass hierarchy and the possible use of neutrinos for society, for nonproliferation of nuclear materials, and geophysics.

  1. Chemical Reactors.

    Science.gov (United States)

    Kenney, C. N.

    1980-01-01

    Describes a course, including content, reading list, and presentation on chemical reactors at Cambridge University, England. A brief comparison of chemical engineering education between the United States and England is also given. (JN)

  2. Microbiological analysis in three diverse natural geothermal bathing pools in Iceland.

    Science.gov (United States)

    Thorolfsdottir, Berglind Osk Th; Marteinsson, Viggo Thor

    2013-03-14

    Natural thermal bathing pools contain geothermal water that is very popular to bathe in but the water is not sterilized, irradiated or treated in any way. Increasing tourism in Iceland will lead to increasing numbers of bath guests, which can in turn affect the microbial flora in the pools and therefore user safety. Today, there is no legislation that applies to natural geothermal pools in Iceland, as the water is not used for consumption and the pools are not defined as public swimming pools. In this study, we conducted a microbiological analysis on three popular but different natural pools in Iceland, located at Lýsuhóll, Hveravellir and Landmannalaugar. Total bacterial counts were performed by flow cytometry, and with plate count at 22 °C, 37 °C and 50 °C. The presence of viable coliforms, Enterococcus spp. and pseudomonads were investigated by growth experiments on selective media. All samples were screened for noroviruses by real time PCR. The results indicate higher fecal contamination in the geothermal pools where the geothermal water flow was low and bathing guest count was high during the day. The number of cultivated Pseudomonas spp. was high (13,000-40,000 cfu/100 mL) in the natural pools, and several strains were isolated and classified as opportunistic pathogens. Norovirus was not detected in the three pools. DNA was extracted from one-liter samples in each pool and analyzed by partial 16S rRNA gene sequencing. Microbial diversity analysis revealed different microbial communities between the pools and they were primarily composed of alpha-, beta- and gammaproteobacteria.

  3. Microbiological Analysis in Three Diverse Natural Geothermal Bathing Pools in Iceland

    Directory of Open Access Journals (Sweden)

    Berglind Osk Th. Thorolfsdottir

    2013-03-01

    Full Text Available Natural thermal bathing pools contain geothermal water that is very popular to bathe in but the water is not sterilized, irradiated or treated in any way. Increasing tourism in Iceland will lead to increasing numbers of bath guests, which can in turn affect the microbial flora in the pools and therefore user safety. Today, there is no legislation that applies to natural geothermal pools in Iceland, as the water is not used for consumption and the pools are not defined as public swimming pools. In this study, we conducted a microbiological analysis on three popular but different natural pools in Iceland, located at Lýsuhóll, Hveravellir and Landmannalaugar. Total bacterial counts were performed by flow cytometry, and with plate count at 22 °C, 37 °C and 50 °C. The presence of viable coliforms, Enterococcus spp. and pseudomonads were investigated by growth experiments on selective media. All samples were screened for noroviruses by real time PCR. The results indicate higher fecal contamination in the geothermal pools where the geothermal water flow was low and bathing guest count was high during the day. The number of cultivated Pseudomonas spp. was high (13,000–40,000 cfu/100 mL in the natural pools, and several strains were isolated and classified as opportunistic pathogens. Norovirus was not detected in the three pools. DNA was extracted from one-liter samples in each pool and analyzed by partial 16S rRNA gene sequencing. Microbial diversity analysis revealed different microbial communities between the pools and they were primarily composed of alpha-, beta- and gammaproteobacteria.

  4. The Association between Anthropometric Variables, Functional Movement Screen Scores and 100 m Freestyle Swimming Performance in Youth Swimmers

    Directory of Open Access Journals (Sweden)

    Daisy Bond

    2015-01-01

    Full Text Available This study examined the association between anthropometric variables, Functional Movement Screen (FMS scores and 100 m freestyle swimming performance in early adolescent swimmers. Fifty competitive, national level, youth swimmers (21 males, 29 females, mean age ± SD = 13.5 ± 1.5 years, age range 11–16 years performed an “all-out” 100 m freestyle (front crawl swim as fast as they could in a 50 m pool. A median divide for 100 m timed swim was also used to divide the sample into faster or slower groups. Height, body mass, skinfolds and limb lengths were also assessed. Maturation was calculated by proxy using anthropometric measures and participants also undertook the FMS as a measure of functional performance. Backwards linear regression indicated a significant model (p = 0.0001, Adjusted R2 = 0.638 explaining 63.8% of the variance in swim performance with total sum of skinfolds, upper leg length, lower leg length, hand length and total height significantly contributing to the model. Swimmers who were classed as fast had lower total sum of skinfolds (p = 0.005 and higher total FMS score (p = 0.005 compared to their slower peers. In summary, this study indicates that anthropometric variables significantly explained the variance in 100 m freestyle swimming performance in youth swimmers.

  5. Reactor Neutrinos

    OpenAIRE

    Lasserre, T.; Sobel, H.W.

    2005-01-01

    We review the status and the results of reactor neutrino experiments, that toe the cutting edge of neutrino research. Short baseline experiments have provided the measurement of the reactor neutrino spectrum, and are still searching for important phenomena such as the neutrino magnetic moment. They could open the door to the measurement of coherent neutrino scattering in a near future. Middle and long baseline oscillation experiments at Chooz and KamLAND have played a relevant role in neutrin...

  6. PHYSIOLOGICAL, BIOMECHANICAL AND ANTHROPOMETRICAL PREDICTORS OF SPRINT SWIMMING PERFORMANCE IN ADOLESCENT SWIMMERS

    Directory of Open Access Journals (Sweden)

    Evelin Lätt

    2010-09-01

    Full Text Available The purpose of this study was to analyze the relationships between 100-m front crawl swimming performance and relevant biomechanical, anthropometrical and physiological parameters in male adolescent swimmers. Twenty five male swimmers (mean ± SD: age 15. 2 ± 1.9 years; height 1.76 ± 0.09 m; body mass 63.3 ± 10.9 kg performed an all-out 100-m front crawl swimming test in a 25-m pool. A respiratory snorkel and valve system with low hydrodynamic resistance was used to collect expired air. Oxygen uptake was measured breath-by-breath by a portable metabolic cart. Swimming velocity, stroke rate (SR, stroke length and stroke index (SI were assessed during the test by time video analysis. Blood samples for lactate measurement were taken from the fingertip pre exercise and at the third and fifth minute of recovery to estimate net blood lactate accumulation (?La. The energy cost of swimming was estimated from oxygen uptake and blood lactate energy equivalent values. Basic anthropometry included body height, body mass and arm span. Body composition parameters were measured using dual-energy X-ray absorptiometry (DXA. Results indicate that biomechanical factors (90.3% explained most of 100-m front crawl swimming performance variability in these adolescent male swimmers, followed by anthropometrical (45.8% and physiological (45.2% parameters. SI was the best single predictor of performance, while arm span and ∆La were the best anthropometrical and physiological indicators, respectively. SI and SR alone explained 92.6% of the variance in competitive performance. These results confirm the importance of considering specific stroke technical parameters when predicting success in young swimmers.

  7. Experimental investigation of particulate debris spreading in a pool

    Energy Technology Data Exchange (ETDEWEB)

    Konovalenko, A., E-mail: kono@kth.se [Division of Nuclear Power Safety, Royal Institute of Technology (KTH) , Roslagstullsbacken 21, Stockholm 106 91 (Sweden); Basso, S., E-mail: simoneb@kth.se [Division of Nuclear Power Safety, Royal Institute of Technology (KTH) , Roslagstullsbacken 21, Stockholm 106 91 (Sweden); Kudinov, P., E-mail: pkudinov@kth.se [Division of Nuclear Power Safety, Royal Institute of Technology (KTH) , Roslagstullsbacken 21, Stockholm 106 91 (Sweden); Yakush, S.E., E-mail: yakush@ipmnet.ru [Institute for Problems in Mechanics of the Russian Academy of Sciences, Ave. Vernadskogo 101 Bldg 1, Moscow 119526 (Russian Federation)

    2016-02-15

    Termination of severe accident progression by core debris cooling in a deep pool of water under reactor vessel is considered in several designs of light water reactors. However, success of this accident mitigation strategy is contingent upon the effectiveness of heat removal by natural circulation from the debris bed. It is assumed that a porous bed will be formed in the pool in the process of core melt fragmentation and quenching. Debris bed coolability depends on its properties and system conditions. The properties of the bed, including its geometry are the outcomes of the debris bed formation process. Spreading of the debris particles in the pool by two-phase turbulent flows induced by the heat generated in the bed can affect the shape of the bed and thus influence its coolability. The goal of this work is to provide experimental data on spreading of solid particles in the pool by large-scale two-phase flow. The aim is to provide data necessary for understanding of separate effects and for development and validation of models and codes. Validated codes can be then used for prediction of debris bed formation under prototypic severe accident conditions. In PDS-P (Particulate Debris Spreading in the Pool) experiments, air injection at the bottom of the test section is employed as a means to create large-scale flow in the pool in isothermal conditions. The test section is a rectangular tank with a 2D slice geometry, it has fixed width (72 mm), adjustable length (up to 1.5 m) and allows water filling to the depth of up to 1 m. Variable pool length and depth allows studying two-phase circulating flows of different characteristic sizes and patterns. The average void fraction in the pool is determined by video recording and subsequent image processing. Particles are supplied from the top of the facility above the water surface. Results of several series of PDS-P experiments are reported in this paper. The influence of the gas flow rate, pool dimensions, particle density

  8. How fast does a seal swim? Variations in swimming behaviour under differing foraging conditions.

    Science.gov (United States)

    Gallon, Susan L; Sparling, Carol E; Georges, Jean-Yves; Fedak, Michael A; Biuw, Martin; Thompson, Dave

    2007-09-01

    The duration of breath-hold dives and the available time for foraging in submerged prey patches is ultimately constrained by oxygen balance. There is a close relationship between swim speed and oxygen utilisation, so it is likely that breath-holding divers optimise their speeds to and from the feeding patch to maximise time spent feeding at depth. Optimal foraging models suggest that transit swim speed should decrease to minimum cost of transport (MCT) speed in deeper and longer duration dives. Observations also suggest that descent and ascent swimming mode and speed may vary in response to changes in buoyancy. We measured the swimming behaviour during simulated foraging of seven captive female grey seals (two adults and five pups). Seals had to swim horizontally underwater from a breathing box to a submerged automatic feeder. The distance to the feeder and the rate of prey food delivery could be varied to simulate different feeding conditions. Diving durations and distances travelled in dives recorded during these experiments were similar to those recorded in the wild. Mean swim speed decreased significantly with increasing distance to the patch, indicating that seals adjusted their speed in response to travel distance, consistent with optimality model predictions. There was, however, no significant relationship between the transit swim speeds and prey density at the patch. Interestingly, all seals swam 10-20% faster on their way to the prey patch compared to the return to the breathing box, despite the fact that any effect of buoyancy on swimming speed should be the same in both directions. These results suggest that the swimming behaviour exhibited by foraging grey seals might be a combination of having to overcome the forces of buoyancy during vertical swimming and also of behavioural choices made by the seals.

  9. Calculation of absorbed doses to water pools in severe accident sequences

    Energy Technology Data Exchange (ETDEWEB)

    Weber, C.F. [Oak Ridge National Lab., TN (United States)

    1991-12-01

    A methodology is presented for calculating the radiation dose to a water pool from the decay of uniformly distributed nuclides in that pool. Motivated by the need to accurately model radiolysis reactions of iodine, direct application is made to fission product sources dissolved or suspended in containment sumps or pools during a severe nuclear reactor accident. Two methods of calculating gamma absorption are discussed - one based on point-kernal integration and the other based on Monte Carlo techniques. Using least-squares minimization, the computed results are used to obtain a correlation that relates absorbed dose to source energy and surface-to-volume ratio of the pool. This correlation is applied to most relevant fission product nuclides and used to actually calculate transient sump dose rate in a pressurized-water reactor (PWR) severe accident sequence.

  10. Conceptual design for the superconducting magnet system of a pulsed DEMO reactor

    Energy Technology Data Exchange (ETDEWEB)

    Duchateau, J.-L., E-mail: jean-luc.duchateau@cea.fr [CEA/IRFM, 13108 St. Paul lez Durance Cedex (France); Hertout, P.; Saoutic, B.; Magaud, P.; Artaud, J.-F.; Giruzzi, G.; Bucalossi, J.; Johner, J.; Sardain, P.; Imbeaux, F.; Ané, J.-M.; Li-Puma, A. [CEA/IRFM, 13108 St. Paul lez Durance Cedex (France)

    2013-10-15

    Highlights: ► A 1D design approach of a pulsed DEMO reactor is presented. ► The main CS and TF conductor design criteria are presented. ► A typical major radius for a 2 GW DEMO is 9 m. ► A typical plasma magnetic field is 4.9 T. ► The pulse duration is 1.85 h for an aspect ratio of 3. -- Abstract: A methodology has been developed to consistently investigate, taking into account main reactor components, possible magnet solutions for a pulsed fusion reactor aiming at a large solenoid flux swing duration within the 2–3 h range. In a conceptual approach, investigations are carried out in the equatorial plane, taking into account the radial extension of the blanket-shielding zone, of the toroidal field magnet system inner leg and of the central solenoid for estimation of the pulsed swing. Design criteria are presented for the radial extension of the superconducting magnets, which is mostly driven by the structures (casings and conductor jacket). Typical available cable current densities are presented as a function of the magnetic field and of the temperature margin. The magnet design criteria have been integrated into SYCOMORE, a code for reactor modeling presently in development at CEA/IRFM in Cadarache, using the tools of the EFDA Integrated Tokamak Modeling task force. Possible solutions are investigated for a 2 GW fusion power reactor with different aspect ratios. The final adjustment of the DEMO pulsed reactor parameters will have to be consistently done, considering all reactor components, when the final goals of the machine will be completely clarified.

  11. Solar energy system demonstration project at Wilmington Swim School, New Castle, Delaware

    Science.gov (United States)

    1980-01-01

    A solar energy system located at the Wilmington Swim School, New Castle, Delaware is described. The system was designed for a 40 percent heating and a 30 percent hot water solar contribution serving the heat loads in the following order: space heat - new addition, domestic water - entire facility, and pool heating - entire facility. On a cost basis for 2920 hours of operation, the heat reclaimed would cost $969.66 annually if provided by gas at 3.79 per million Btu's. At 5.5 centers per kwh, heat recovery costs of $481.80 percent a net savings of $487.86 annually.

  12. Cooling Performance of Natural Circulation for a Research Reactor

    Energy Technology Data Exchange (ETDEWEB)

    Park, Suki; Chun, J. H.; Yum, S. B. [Korea Atomic Energy Research Institute, Daejeon (Korea, Republic of)

    2015-10-15

    This paper deals with the core cooling performance by natural circulation during normal operation and a flow channel blockage event in an open tank-in-pool type research reactor. The cooling performance is predicted by using the RELAP5/ MOD3.3 code. The core decay heat is usually removed by natural circulation to the reactor pool water in open tank-in-pool type research reactors with the thermal power less than several megawatts. Therefore, these reactors have generally no active core cooling system against a loss of normal forced flow. In reactors with the thermal power less than around one megawatt, the reactor core can be cooled down by natural circulation even during normal full power operation. The cooling performance of natural circulation in an open tank-in-pool type research reactor has been investigated during the normal natural circulation and a flow channel blockage event. It is found that the maximum powers without void generation at the hot channel are around 1.16 MW and 820 kW, respectively, for the normal natural circulation and the flow channel blockage event.

  13. Sandia National Laboratories Medical Isotope Reactor concept.

    Energy Technology Data Exchange (ETDEWEB)

    Coats, Richard Lee; Dahl, James J.; Parma, Edward J., Jr.

    2010-04-01

    This report describes the Sandia National Laboratories Medical Isotope Reactor and hot cell facility concepts. The reactor proposed is designed to be capable of producing 100% of the U.S. demand for the medical isotope {sup 99}Mo. The concept is novel in that the fuel for the reactor and the targets for the {sup 99}Mo production are the same. There is no driver core required. The fuel pins that are in the reactor core are processed on a 7 to 21 day irradiation cycle. The fuel is low enriched uranium oxide enriched to less than 20% {sup 235}U. The fuel pins are approximately 1 cm in diameter and 30 to 40 cm in height, clad with Zircaloy (zirconium alloy). Approximately 90 to 150 fuel pins are arranged in the core in a water pool {approx}30 ft deep. The reactor power level is 1 to 2 MW. The reactor concept is a simple design that is passively safe and maintains negative reactivity coefficients. The total radionuclide inventory in the reactor core is minimized since the fuel/target pins are removed and processed after 7 to 21 days. The fuel fabrication, reactor design and operation, and {sup 99}Mo production processing use well-developed technologies that minimize the technological and licensing risks. There are no impediments that prevent this type of reactor, along with its collocated hot cell facility, from being designed, fabricated, and licensed today.

  14. Sex differences associated with intermittent swim stress.

    Science.gov (United States)

    Warner, Timothy A; Libman, Matthew K; Wooten, Katherine L; Drugan, Robert C

    2013-11-01

    Various animal models of depression have been used to seek a greater understanding of stress-related disorders. However, there is still a great need for novel research in this area, as many individuals suffering from depression are resistant to current treatment methods. Women have a higher rate of depression, highlighting the need to investigate mechanisms of sex differences. Therefore, we employed a new animal model to assess symptoms of depression, known as intermittent swim stress (ISS). In this model, the animal experiences 100 trials of cold water swim stress. ISS has already been shown to cause signs of behavioral depression in males, but has yet to be assessed in females. Following ISS exposure, we looked at sex differences in the Morris water maze and forced swim test. The results indicated a spatial learning effect only in the hidden platform task between male and female controls, and stressed and control males. A consistent spatial memory effect was only seen for males exposed to ISS. In the forced swim test, both sexes exposed to ISS exhibited greater immobility, and the same males and females also showed attenuated climbing and swimming, respectively. The sex differences could be due to different neural substrates for males and females. The goal of this study was to provide the first behavioral examination of sex differences following ISS exposure, so the stage of estrous cycle was not assessed for the females. This is a necessary future direction for subsequent experiments. The current article highlights the importance of sex differences in response to stress.

  15. Switching of swimming modes in Magnetospirillium gryphiswaldense

    CERN Document Server

    Reufer, Mathias; Schwarz-Linek, Jana; Martinez, Vincent A; Morozov, Alexander N; Arlt, Jochen; Trubitsyn, Denis; Ward, Bruce; Poon, Wilson C K

    2013-01-01

    The microaerophilic magnetotactic bacterium Magnetospirillum gryphiswaldense swims along magnetic field lines using a single flagellum at each cell pole. It is believed that this magnetotactic behavior enables cells to seek optimal oxygen concentration with maximal efficiency. We analyse the trajectories of swimming M. gryphiswaldense cells in external magnetic fields larger than the earth's field, and show that each cell can switch very rapidly (in < 0.2 s) between a fast and a slow swimming mode. Close to a glass surface, a variety of trajectories was observed, from straight swimming that systematically deviates from field lines to various helices. A model in which fast (slow) swimming is solely due to the rotation of the trailing (leading) flagellum can account for these observations. We determined the magnetic moment of this bacterium using a new method, and obtained a value of (2.0 $\\pm$ 0.6) $\\times$ $10^{-16}$ Am$^2$. This value is found to be consistent with parameters emerging from quantitative fi...

  16. Quercetin alters energy metabolism in swimming mice.

    Science.gov (United States)

    Wu, Jianquan; Gao, Weina; Wei, Jingyu; Yang, Jijun; Pu, Lingling; Guo, Changjiang

    2012-10-01

    Quercetin has been demonstrated to be effective in increasing physical endurance in mice and humans. However, the mechanisms involved are not fully understood. In this study, male Kunming mice were fed a diet containing 0.1% quercetin for 14 days before swimming for 60 min. The overall serum metabolic profile was investigated by a ¹H nuclear magnetic resonance-based metabolomic approach. Serum glucose, lactate, nonesterified fatty acids (NEFA), and nonprotein nitrogen (NPN), as well as hepatic and muscular glycogen were measured biochemically. The results of metabolomic analysis showed that swimming induced a significant change in serum metabolic profile. Relative increases in the levels of lactate, alanine, low-density lipoprotein-very low-density lipoprotein, and unsaturated fatty acids, and decreases in choline, phosphocholine, and glucose were observed after swimming. With quercetin supplementation, these changes were attenuated. The results of biochemical assays were consistent with the data obtained from metabolomic analysis, in that serum NEFA was increased while lactate and NPN decreased after exposed to quercetin in swimming mice. Similar change in NEFA was also found in liver and gastrocnemius muscle tissues. Our current findings suggest that quercetin alters energy metabolism in swimming mice and increased lipolysis may contribute to the actions of quercetin on physical endurance.

  17. Sink or Swim in the Labor Pool: Determinants and Consequences of Teenage Employment

    Science.gov (United States)

    Voloshin, Irina

    2012-01-01

    A majority of all high school students engage in the labor force by the time they complete their senior year. Few studies have investigated the long-term educational trajectories of student workers after high school graduation. Even fewer research studies have concerned themselves with ascriptive stratification patterns of the teenage labor…

  18. Operating experiences with rotary air-to-air heat exchangers: hospitals, schools, nursing homes, swimming pools

    Energy Technology Data Exchange (ETDEWEB)

    Pearson, R.J.

    1976-01-01

    Systems utilizing rotary air-to-air heat exchangers are discussed. Basic considerations of use (fresh air requirements, system configurations, cost considerations), typical system layout/design considerations, and operating observations by engineers, staff and maintenance personnel are described.

  19. Simulation of power excursions - Osiris reactor; Simulation des excursions de puissance - pile Osiris

    Energy Technology Data Exchange (ETDEWEB)

    Pascouet, A. [Commissariat a l' Energie Atomique, Saclay (France). Centre d' Etudes Nucleaires

    1964-07-01

    Following the experimental work accomplished in the U.S.A. on Borax 1 and SPERT 1 and the accident of SL 1, the 'Commissariat a l'Energie Atomique' started a research program about the safety of its own swimming Pool reactors, with regard to power excursions. The first research work led to the design of programmed explosive charges, adapted to the simulation of a power excursion. This report describes the application of these methods to the investigation of Osiris safety. (author) [French] A la suite des essais effectues aux U.S.A. sur BORAX 1 et SPERT 1 et de l'accident survenu a SL 1, le Commissariat a l'Energie Atomique a lance un programme d'etudes sur la surete de ses reacteurs piscines vis-a-vis des excursions de puissance. Les premieres etudes ont abouti A la mise au point de charges programmees capables de simuler une excursion de puissance. On trouvera dans le present rapport l'application de ces methodes a l'etude de la surete d'OSIRIS. (auteur)

  20. Development of Scaling Approach for Prediction of Terminal Spread Thickness of Melt Poured into a Pool of Water

    OpenAIRE

    Konovalenko, Alexander; Kudinov, Pavel

    2012-01-01

    Corium melt stabilization and long term cooling in a pool of water located beneath reactor vessel is adopted in several existing designs of light water reactors (LWRs) as an element in severe accident (SA) mitigation strategy. At certain conditions of melt release into the pool (e.g. large ratio of the vessel breach size to the pool depth), liquid melt can spread under water and reach a coolable configuration. Coolability of the melt is contingent on terminal spread thickness of the melt laye...

  1. Rank Pooling for Action Recognition.

    Science.gov (United States)

    Fernando, Basura; Gavves, Efstratios; Oramas M, Jose Oramas; Ghodrati, Amir; Tuytelaars, Tinne

    2017-04-01

    We propose a function-based temporal pooling method that captures the latent structure of the video sequence data - e.g., how frame-level features evolve over time in a video. We show how the parameters of a function that has been fit to the video data can serve as a robust new video representation. As a specific example, we learn a pooling function via ranking machines. By learning to rank the frame-level features of a video in chronological order, we obtain a new representation that captures the video-wide temporal dynamics of a video, suitable for action recognition. Other than ranking functions, we explore different parametric models that could also explain the temporal changes in videos. The proposed functional pooling methods, and rank pooling in particular, is easy to interpret and implement, fast to compute and effective in recognizing a wide variety of actions. We evaluate our method on various benchmarks for generic action, fine-grained action and gesture recognition. Results show that rank pooling brings an absolute improvement of 7-10 average pooling baseline. At the same time, rank pooling is compatible with and complementary to several appearance and local motion based methods and features, such as improved trajectories and deep learning features.

  2. Respiratory Function and Changes in Lung Epithelium Biomarkers after a Short-Training Intervention in Chlorinated vs. Ozone Indoor Pools

    Science.gov (United States)

    Fernández-Luna, Álvaro; Gallardo, Leonor; Plaza-Carmona, María; García-Unanue, Jorge; Sánchez-Sánchez, Javier; Felipe, José Luis; Burillo, Pablo; Ara, Ignacio

    2013-01-01

    Background Swimming in indoor pools treated with combined chemical treatments (e.g. ozone) may reduce direct exposure to disinfection byproducts and thus have less negative effects on respiratory function compared to chlorinated pools. The aim of this study is to analyze the effects of a short-term training intervention on respiratory function and lung epithelial damage in adults exercising in indoor swimming pool waters treated with different disinfection methods (chlorine vs. ozone with bromine). Methods Lung permeability biomakers [surfactant protein D (SP-D) and Clara cell secretory protein (CC16) in plasma] and forced expiratory volumes and flow (FEV1, FVC and FEF25–75) were measured in 39 healthy adults. Thirteen participants swam during 20 sessions in a chlorinated pool (CP), 13 performed and equivolumic intervention in an ozone pool (OP) and 13 were included in a control group (CG) without exposition. Results Median plasma CC16 levels increased in CP swimmers (4.27±3.29 and 6.62±5.51 µg/L, p = 0.01, pre and post intervention respectively) while no significant changes in OP and CG participants were found. No significant changes in median plasma SP-D levels were found in any of the groups after the training period. FVC increased in OP (4.26±0.86 and 4.43±0.92 L, pchlorinated treated pools. PMID:23874631

  3. Experimental determination of nuclear parameters for RP-0 reactor core; Determinacion experimental de los parametros nucleares para el nucleo tipo MTR del reactor nuclear RP-0

    Energy Technology Data Exchange (ETDEWEB)

    Cajacuri, Rafael A. [Sao Paulo Univ., SP (Brazil). Inst. de Fisica

    2000-07-01

    In the nuclear reactor for investigations RP-0 which is in Lima, Peru, that is a open pool class reactor with 1 to 10 watts of power and as a nuclear fuel uranium 238 enriched to 20% constituted by elements of Material Testing Reactor fuel class. This has reflectors of graphite and moderator of water demineralized. In 1996/1997 was measured in this reactor the following parameters: position of the control bar that make critic the reactor, critic height of moderator, excess of reactivity of the nucleus, parameter of reactivity for vacuum, parameter of reactivity for temperature, reactivity of its control bar, levels of doses in the reactor. (author)

  4. Undulatory swimming in fluids with polymer networks

    CERN Document Server

    Gagnon, D A; Arratia, P E

    2013-01-01

    The motility behavior of the nematode Caenorhabditis elegans in polymeric solutions of varying concentrations is systematically investigated in experiments using tracking and velocimetry methods. As the polymer concentration is increased, the solution undergoes a transition from the semi-dilute to the concentrated regime, where these rod-like polymers entangle, align, and form networks. Remarkably, we find an enhancement in the nematode's swimming speed of approximately 65% in concentrated solutions compared to semi-dilute solutions. Using velocimetry methods, we show that the undulatory swimming motion of the nematode induces an anisotropic mechanical response in the fluid. This anisotropy, which arises from the fluid micro-structure, is responsible for the observed increase in swimming speed.

  5. Undulatory swimming in shear-thinning fluids

    CERN Document Server

    Gagnon, David A; Arratia, Paulo E

    2014-01-01

    The swimming behaviour of microorganisms can be strongly influenced by the rheology of their fluid environment. In this manuscript, we experimentally investigate the effects of shear-thinning viscosity on the swimming behaviour of an undulatory swimmer, the nematode Caenorhabditis elegans. Tracking methods are used to measure the swimmer's kinematic data (including propulsion speed) and velocity fields. We find that shear-thinning viscosity modifies the velocity fields produced by the swimming nematode but does not modify the nematode's speed and beating kinematics. Velocimetry data show significant enhancement in local vorticity and circulation, and an increase in fluid velocity near the nematode's tail, compared to Newtonian fluids of similar effective viscosity. These findings are in good agreement with recent theoretical and numerical results.

  6. The swimming mechanics of Artemia Salina

    Science.gov (United States)

    Ruiz-Angulo, A.; Ramos-Musalem, A. K.; Zenit, R.

    2013-11-01

    An experimental study to analyze the swimming strategy of a small crustacean (Artemia Salina) was conducted. This animal has a series of eleven pairs of paddle-like appendices in its thorax. These legs move in metachronal-wave fashion to achieve locomotion. To quantify the swimming performance, both high speed video recordings of the legs motion and time-resolved PIV measurements of the induced propulsive jet were conducted. Experiments were conducted for both tethered and freely swimming specimens. We found that despite their small size, the propulsion is achieved by an inertial mechanism. An analysis of the efficiency of the leg wave-like motion is presented and discussed. A brief discussion on the mixing capability of the induced flow is also presented.

  7. Effects of hydrodynamic interactions in bacterial swimming.

    Science.gov (United States)

    Chattopadhyay, Suddhashil; Lun Wu, Xiao

    2008-03-01

    The lack of precise experimental data has prevented the investigation of the effects of long range hydrodynamic interactions in bacterial swimming. We perform measurements on various strains of bacteria with the aid of optical tweezers to shed light on this aspect of bacterial motility. Geometrical parameters recorded by fluorescence microscopy are used with theories which model flagella propulsion (Resistive force theory & Lighthill's formulation which includes long range interactions). Comparison of the predictions of these theories with experimental data, observed directly from swimming bacterium, led to the conclusion that while long range inetractions were important for single polar flagellated strains (Vibrio Alginolyticus & Caulobacter Crescentus), local force theory was adequate to describe the swimming of multi-flagellated Esherichia Coli. We performed additional measurements on E. Coli minicells (miniature cells with single polar flagellum) to try and determine the cause of this apparent effect of shielding of long range interactions in multiple flagellated bacteria.

  8. Undulatory Swimming in Fluids with Polymer Networks

    Science.gov (United States)

    Gagnon, David; Shen, Xiaoning; Arratia, Paulo

    2013-11-01

    In this talk, we systematically investigate the motility behavior of the nematode Caenorhabditis elegans in polymeric solutions of varying concentration using tracking and velocimetry methods. As the polymer concentration is increased, the solution undergoes a transition from the semi-dilute to the concentrated regime, where these rod-like polymers entangle, align, and form networks. Remarkably, we find an enhancement in the nematode's swimming speed of approximately 65 percent in concentrated solutions compared to semi-dilute solutions. Using velocimetry methods, we show that the undulatory swimming motion of the nematode induces an anisotropic mechanical response in the fluid. This anisotropy, which arises from the fluid micro-structure, is responsible for the observed increase in swimming speed. This work was supported by NSF CAREER (CBET) 0954084.

  9. Flow analysis of C. elegans swimming

    Science.gov (United States)

    Montenegro-Johnson, Thomas; Gagnon, David; Arratia, Paulo; Lauga, Eric

    2015-11-01

    Improved understanding of microscopic swimming has the potential to impact numerous biomedical and industrial processes. A crucial means of analyzing these systems is through experimental observation of flow fields, from which it is important to be able to accurately deduce swimmer physics such as power consumption, drag forces, and efficiency. We examine the swimming of the nematode worm C. elegans, a model system for undulatory micro-propulsion. Using experimental data of swimmer geometry and kinematics, we employ the regularized stokeslet boundary element method to simulate the swimming of this worm outside the regime of slender-body theory. Simulated flow fields are then compared with experimentally extracted values confined to the swimmer beat plane, demonstrating good agreement. We finally address the question of how to estimate three-dimensional flow information from two-dimensional measurements.

  10. Estimating energy expenditure during front crawl swimming using accelerometers

    DEFF Research Database (Denmark)

    Nordsborg, Nikolai Baastrup; Espinosa, Hugo G.; Van Thiel, David H

    2014-01-01

    The determination of energy expenditure is of major interest in training load and performance assessment. Small, wireless accelerometer units have the potential to characterise energy expenditure during swimming. The correlation between absorbed oxygen versus flume swimming speed and absorbed...

  11. A Study of a Mechanical Swimming Dolphin

    Science.gov (United States)

    Fang, Lilly; Maass, Daniel; Leftwich, Megan; Smits, Alexander

    2007-11-01

    A one-third scale dolphin model was constructed to investigate dolphin swimming hydrodynamics. Design and construction of the model were achieved using body coordinate data from the common dolphin (Delphinus delphis) to ensure geometric similarity. The front two-thirds of the model are rigid and stationary, while an external mechanism drives the rear third. This motion mimics the kinematics of dolphin swimming. Planar laser induced florescence (PLIF) and particle image velocimetry (PIV) are used to study the hydrodynamics of the wake and to develop a vortex skeleton model.

  12. Instabilities in the Swimming of Bacteria

    Science.gov (United States)

    Riley, Emily; Lauga, Eric

    2016-11-01

    Peritrichously flagellated bacteria, such as E. coli and B. subtillis, have flagella randomly distributed over their body. These flagella rotate to generate a pushing force that causes the cell to swim body first. For changes in direction these flagella return to their randomly distributed state where the flagella point in many different directions. The main observed state of swimming peritrichously flagellated bacteria however is one where all their flagella gathered or bundled at one end of the body. In this work we address this problem from the point of view of fluid-structure interactions and show theoretically and numerically how the conformation of flagella depends on the mechanics of the cell.

  13. Swimming Efficiency of Bacterium Escherichia Coli

    CERN Document Server

    Chattopadhyay, S; Wu, X L; Yeung, C; Chattopadhyay, Suddhashil; Moldovan, Radu; Yeung, Chuck

    2005-01-01

    We use in vivo measurements of swimming bacteria in an optical trap to determine fundamental properties of bacterial propulsion. In particular, we determine the propulsion matrix, which relates the angular velocity of the flagellum to the torques and forces propelling the bacterium. From the propulsion matrix dynamical properties such as forces, torques, swimming speed and power can be obtained from measurements of the angular velocity of the motor. We find significant heterogeneities among different individuals even though all bacteria started from a single colony. The propulsive efficiency, defined as the ratio of the propulsive power output to the rotary power input provided by the motors, is found to be 0.2%.

  14. Solar energy system demonstration project at Wilmington Swim School, New Castle, Delaware. Final report

    Energy Technology Data Exchange (ETDEWEB)

    None

    1980-07-01

    This document is the Final Report of the Solar Energy System located at the Wilmington, Swim School, New Castle, Delaware. This active solar system is composed of 2,700 square feet of Revere liquid flat plate collectors piped to a 2,800 gallon concrete storage tank located below ground near the building. A micro-computer based control system selects the optimal applications of the stored energy among space, domestic water and pool alternatives. The controlled logic is planned for serving the heat loads in the following order: space heat-new addition, domestic water-entire facility, and pool heating-entire facility. A modified trombe wall passive operation the active system will bypass the areas being served passively. The system was designed for a 40 percent heating and a 30 percent hot water solar contribution.

  15. Ion-swimming speed variation of Vibrio cholerae cells

    Indian Academy of Sciences (India)

    Anindito Sen; Ranjan K Nandi; Amar N Ghosh

    2005-09-01

    In the present work we report the variation in swimming speed of Vibrio cholerae with respect to the change in concentration of sodium ions in the medium. We have also studied the variation in swimming speed with respect to temperature. We find that the swimming speed initially shows a linear increase with the increase of the sodium ions in the medium and then plateaus. The range within which the swimming speed attains saturation is approximately the same at different temperatures.

  16. Conditioned ethanol aversion in rats induced by voluntary wheel running, forced swimming, and electric shock: an implication for aversion therapy of alcoholism.

    Science.gov (United States)

    Nakajima, Sadahiko

    2004-01-01

    This study was planned to demonstrate rats' acquisition of aversion to ethanol solution consumed before voluntary running, forced swimming, or electric shock delivery. Wistar rats under water deprivation were allotted to four groups of eight rats each, and all rats were allowed to drink 5% ethanol solution for 15 min. Immediately after the ethanol drinking, rats of Group Run were put into the individual running wheels for 15 min, those of Group Swim were put into the individual swimming pools for 15 min, those of Group Shock received electric shocks for 15 min (15 0.45-mA shocks of 0.7s with the intershock interval of 1 min) in the individual small chambers, and those of Group Control were directly returned back to the home cages. This procedure was repeated for six days, followed by a two-day choice test of ethanol aversion where a bottle containing 5% ethanol solution and a bottle of tap water were simultaneously presented for 15 min. In the test, Groups Run, Swim, and Shock drank ethanol solution significantly less than tapwater, while Group Control drank both fluids equally. The effects of running, swimming, and shock were equivalent. The successful demonstration of acquired ethanol aversion induced by exercise (running and swimming) or shock in rats suggests an avenue for clinical application of exercise and shock treatments for human alcoholics, though there are many issues to be resolved before the practical use.

  17. 77 FR 14700 - Safety Zones; Swim Around Charleston, Charleston, SC

    Science.gov (United States)

    2012-03-13

    ... notice regarding our public dockets in the January 17, 2008, issue of the Federal Register (73 FR 3316... SECURITY Coast Guard 33 CFR Part 165 RIN 1625-AA00 Safety Zones; Swim Around Charleston, Charleston, SC... establish temporary moving safety zones during the Swim Around Charleston, a swimming race occurring on...

  18. 76 FR 38586 - Safety Zone; Swim Around Charleston, Charleston, SC

    Science.gov (United States)

    2011-07-01

    ... Federal Register (73 FR 3316). Public Meeting We do not now plan to hold a public meeting. But you may... SECURITY Coast Guard 33 CFR Part 165 RIN 1625-AA00 Safety Zone; Swim Around Charleston, Charleston, SC... establish a temporary moving safety zone during the Swim Around Charleston, a swimming race occurring...

  19. 78 FR 54583 - Safety Zone; Swim Around Charleston, Charleston, SC

    Science.gov (United States)

    2013-09-05

    ..., telephone 202-366-9826. SUPPLEMENTARY INFORMATION: Table of Acronyms DHS Department of Homeland Security FR... SECURITY Coast Guard 33 CFR Part 165 RIN 1625-AA00 Safety Zone; Swim Around Charleston, Charleston, SC... temporary moving safety zone during the Swim Around Charleston, a swimming race occurring on waters of...

  20. 13 CFR 120.1706 - Pool Originator's retained interest in Pool.

    Science.gov (United States)

    2010-01-01

    ... 13 Business Credit and Assistance 1 2010-01-01 2010-01-01 false Pool Originator's retained interest in Pool. 120.1706 Section 120.1706 Business Credit and Assistance SMALL BUSINESS ADMINISTRATION... Pools § 120.1706 Pool Originator's retained interest in Pool. The Pool Originator must retain...

  1. Sonochemical Reactors.

    Science.gov (United States)

    Gogate, Parag R; Patil, Pankaj N

    2016-10-01

    Sonochemical reactors are based on the generation of cavitational events using ultrasound and offer immense potential for the intensification of physical and chemical processing applications. The present work presents a critical analysis of the underlying mechanisms for intensification, available reactor configurations and overview of the different applications exploited successfully, though mostly at laboratory scales. Guidelines have also been presented for optimum selection of the important operating parameters (frequency and intensity of irradiation, temperature and liquid physicochemical properties) as well as the geometric parameters (type of reactor configuration and the number/position of the transducers) so as to maximize the process intensification benefits. The key areas for future work so as to transform the successful technique at laboratory/pilot scale into commercial technology have also been discussed. Overall, it has been established that there is immense potential for sonochemical reactors for process intensification leading to greener processing and economic benefits. Combined efforts from a wide range of disciplines such as material science, physics, chemistry and chemical engineers are required to harness the benefits at commercial scale operation.

  2. Fission product concentration evolution in sodium pool following a fuel subassembly failure in an LMFBR

    Energy Technology Data Exchange (ETDEWEB)

    Natesan, K.; Velusamy, K.; Selvaraj, P.; Kasinathan, N.; Chellapandi, P.; Chetal, S.; Bhoje, S. [Indira Gandhi Center for Atomic Research, Kalpakkam (India)

    2003-07-01

    During a fuel element failure in a liquid metal cooled fast breeder reactor, the fission products originating from the failed pins mix into the sodium pool. Delayed Neutron Detectors (DND) are provided in the sodium pool to detect such failures by way of detection of delayed neutrons emitted by the fission products. The transient evolution of fission product concentration is governed by the sodium flow distribution in the pool. Transient hydraulic analysis has been carried out using the CFD code PHOENICS to estimate fission product concentration evolution in hot pool. k- {epsilon} turbulence model and zero laminar diffusivity for the fission product concentration have been considered in the analysis. Times at which the failures of various fuel subassemblies (SA) are detected by the DND are obtained. It has been found that in order to effectively detect the failure of every fuel SA, a minimum of 8 DND in hot pool are essential.

  3. PFOS affects posterior swim bladder chamber inflation and swimming performance of zebrafish larvae.

    Science.gov (United States)

    Hagenaars, A; Stinckens, E; Vergauwen, L; Bervoets, L; Knapen, D

    2014-12-01

    Perfluorooctane sulphonate (PFOS) is one of the most commonly detected perfluorinated alkylated substances in the aquatic environment due to its persistence and the degradation of less stable compounds to PFOS. PFOS is known to cause developmental effects in fish. The main effect of PFOS in zebrafish larvae is an uninflated swim bladder. As no previous studies have focused on the effect of PFOS on zebrafish swim bladder inflation, the exact mechanisms leading to this effect are currently unknown. The objective of this study was to determine the exposure windows during early zebrafish development that are sensitive to PFOS exposure and result in impaired swim bladder inflation in order to specify the mechanisms by which this effect might be caused. Seven different time windows of exposure (1-48, 1-72, 1-120, 1-144, 48-144, 72-144, 120-144h post fertilization (hpf)) were tested based on the different developmental stages of the swim bladder. These seven time windows were tested for four concentrations corresponding to the EC-values of 1, 10, 80 and 95% impaired swim bladder inflation (EC1=0.70 mg L(-1), EC10=1.14 mg L(-1), EC80=3.07 mg L(-1) and EC95=4.28 mg L(-1)). At 6 days post fertilization, effects on survival, hatching, swim bladder inflation and size, larval length and swimming performance were assessed. For 0.70 mg L(-1), no significant effects were found for the tested parameters while 1.14 mg L(-1) resulted in a reduction of larval length. For 3.07 and 4.28 mg L(-1), the number of larvae affected and the severity of effects caused by PFOS were dependent on the time window of exposure. Exposure for 3 days or more resulted in significant reductions of swim bladder size, larval length and swimming speed with increasing severity of effects when the duration of exposure was longer, suggesting a possible effect of accumulated dose. Larvae that were only exposed early (1-48 hpf) or late (120-144 hpf) during development showed no effects on the studied endpoints

  4. Healthy Swimming Is a Partnership Effort

    Science.gov (United States)

    Grosse, Susan J.

    2009-01-01

    While one cannot control the water chemistry, he/she can control personal hygiene and facility cleanliness. Giardia and cryptosporidium (crypto) are only two of the many recreational water illnesses (RWIs) that can turn happy swim memories into serious illness situations. In this article, the author discusses three factors that determine how…

  5. Anaerobic critical velocity in four swimming techniques.

    Science.gov (United States)

    Neiva, H P; Fernandes, R J; Vilas-Boas, J P

    2011-03-01

    The aim of this study was to assess critical velocity in order to control and evaluate anaerobic swimming training. 51 highly trained male swimmers performed maximal 15, 25, 37.5 and 50 m in the 4 swimming techniques to determine critical velocity from the distance-time relationship. Anaerobic critical velocity was compared with 100 m swimming performance and corresponding partials. Complementarily, 9 swimmers performed a 6×50 m (4 min interval) training series at front crawl individual anaerobic critical velocity, capillary blood lactate concentrations being assessed after each repetition. The mean±SD values of anaerobic critical velocity and its relationship with the 100 m event were: 1.61±0.07 (r=0.60, p=0.037), 1.53±0.05 (r=0.81, p=0.015), 1.33±0.05 (r=0.83, p=0.002), and 1.75±0.05 (r=0.74, p=0.001), for butterfly, backstroke, breaststroke and front crawl, respectively. However, differences between anaerobic critical velocity and performance were observed (with exception of the second half of the 100 m swimming events in breaststroke and butterfly). Lactate concentration values at the end of the series were 14.52±1.06 mmol.l (-1), which suggests that it was indeed an anaerobic training set. In this sense, anaerobic critical velocity can be used to prescribe anaerobic training intensities.

  6. Low Reynolds number swimming and controllability

    Directory of Open Access Journals (Sweden)

    Alouges F.

    2013-12-01

    Full Text Available The modeling of swimming at the micro scale, either for biological understanding of microorganisms’ motility, e.g. bacteria, or for the conceptual building of small mechanisms capable of underwater displacement, involves low Reynolds number flows. This paper is a short review of recent links unveiled by the author and his collaborators between this problem and control theory.

  7. Swimming of the pea crab (Pinnotheres pisum)

    NARCIS (Netherlands)

    Versteegh, C.P.C.; Muller, M.

    2014-01-01

    Aquatic organisms have to deal with different hydrodynamic regimes, depending on their size and speed during locomotion. The pea crab swims by beating the third and fourth pereiopod on opposite sides as pairs. Using particle tracking velocimetry and high-speed video recording, we quantify the kinema

  8. Accumulation of swimming bacteria near an interface

    Science.gov (United States)

    Tang, Jay; Li, Guanglai

    2012-11-01

    Microbes inhabit planet earth over billions of years and have adapted to diverse physical environment of water, soil, and particularly at or near interfaces. We focused our attention on the locomotion of Caulobacter crescentus, a singly flagellated bacterium, at the interface of water/solid or water/air. We measured the distribution of a forward swimming strain of C. crescentus near a surface using a three-dimensional tracking technique based on dark field microscopy and found that the swimming bacteria accumulate heavily within a micrometer from the surface. We attribute this accumulation to frequent collisions of the swimming cells with the surface, causing them to align parallel to the surface as they continually move forward. The extent of accumulation at the steady state is accounted for by balancing alignment caused by these collisions with rotational Brownian motion of the micrometer-sized bacteria. We performed a simulation based on this model, which reproduced the measured results. Additional simulations demonstrate the dependence of accumulation on swimming speed and cell size, showing that longer and faster cells accumulate more near a surface than shorter and slower ones do. The overarching goal of our study is to describe interfacial microbial behavior through detailed analysis of their motion. We acknowledge support by NSF PHY 1058375.

  9. Assisted and resisted sprint training in swimming.

    Science.gov (United States)

    Girold, Sébastien; Calmels, Paul; Maurin, Didier; Milhau, Nicolas; Chatard, Jean-Claude

    2006-08-01

    This study was undertaken to determine whether the resisted-sprint in overstrength (OSt) or the assisted-sprint in overspeed (OSp) could be efficient training methods to increase 100-m front crawl performance. Thirty-seven (16 men, 21 women) competition-level swimmers (mean +/- SD: age 17.5 +/- 3.5 years, height 173 +/- 14 cm, weight 63 +/- 14 kg) were randomly divided into 3 groups: OSt, OSp, and control (C). All swimmers trained 6 days per week for 3 weeks, including 3 resisted or assisted training sessions per week for the groups OSt and OSp respectively. Elastic tubes were used to generate swimming overstrength and overspeed. Three 100-m events were performed before, during, and after the training period. Before each 100-m event, strength of the elbow flexors and extensors was measured with an isokinetic dynamometer. Stroke rate and stroke length were evaluated using the video-recorded 100-m events. In the OSt group, elbow extensor strength, swimming velocity, and stroke rate significantly increased (p < 0.05), while stroke length remained unchanged after the 3-week training period. In the OSp group, stroke rate significantly increased (p < 0.05) and stroke length significantly decreased (p < 0.05) without changes in swimming velocity. No significant variations in the C group were observed. Both OSt and OSp proved to be more efficient than the traditional training program. However, the OSt training program had a larger impact on muscle strength, swimming performance, and stroke technique than the OSp program.

  10. Can phoretic particles swim in two dimensions?

    Science.gov (United States)

    Sondak, David; Hawley, Cory; Heng, Siyu; Vinsonhaler, Rebecca; Lauga, Eric; Thiffeault, Jean-Luc

    2016-12-01

    Artificial phoretic particles swim using self-generated gradients in chemical species (self-diffusiophoresis) or charges and currents (self-electrophoresis). These particles can be used to study the physics of collective motion in active matter and might have promising applications in bioengineering. In the case of self-diffusiophoresis, the classical physical model relies on a steady solution of the diffusion equation, from which chemical gradients, phoretic flows, and ultimately the swimming velocity may be derived. Motivated by disk-shaped particles in thin films and under confinement, we examine the extension to two dimensions. Because the two-dimensional diffusion equation lacks a steady state with the correct boundary conditions, Laplace transforms must be used to study the long-time behavior of the problem and determine the swimming velocity. For fixed chemical fluxes on the particle surface, we find that the swimming velocity ultimately always decays logarithmically in time. In the case of finite Péclet numbers, we solve the full advection-diffusion equation numerically and show that this decay can be avoided by the particle moving to regions of unconsumed reactant. Finite advection thus regularizes the two-dimensional phoretic problem.

  11. Intermittent Swimming with a Flexible Propulsor

    Science.gov (United States)

    Akoz, Emre; Zeyghami, Samane; Moored, Keith

    2016-11-01

    Some animals propel themselves by using an intermittent swimming gait known as a burst-and-glide or a burst-and-coast motion. These swimmers tend to have a more pronounced pitching of their caudal fins than heaving leading to low non-dimensional heave-to-pitch ratios. Recent work has shown that when this ratio is sufficiently low the efficiency of an intermittently heaving/pitching airfoil can be significantly improved over a continuously oscillating airfoil. However, fish that swim with an intermittent gait, such as cod and saithe, do not have rigid fins, but instead have highly flexible fins. To examine the performance and flow structures of an intermittent swimmer with a flexible propulsor, a fast boundary element method solver strongly coupled with a torsional-spring structural model was developed. A self-propelled virtual body combined with a flexible-hinged pitching airfoil is used to model a free-swimming animal and its flexible caudal fin. The duty cycle of the active to the coasting phase of motion, the torsional spring flexibility and the forcing frequency are all varied. The cost-of-transport and the swimming speed are measured and connected to the observed wake patterns. Supported by the Office of Naval Research under Program Director Dr. Bob Brizzolara, MURI Grant Number N00014-14-1-0533.

  12. Swimming in air-breathing fishes.

    Science.gov (United States)

    Lefevre, S; Domenici, P; McKenzie, D J

    2014-03-01

    Fishes with bimodal respiration differ in the extent of their reliance on air breathing to support aerobic metabolism, which is reflected in their lifestyles and ecologies. Many freshwater species undertake seasonal and reproductive migrations that presumably involve sustained aerobic exercise. In the six species studied to date, aerobic exercise in swim flumes stimulated air-breathing behaviour, and there is evidence that surfacing frequency and oxygen uptake from air show an exponential increase with increasing swimming speed. In some species, this was associated with an increase in the proportion of aerobic metabolism met by aerial respiration, while in others the proportion remained relatively constant. The ecological significance of anaerobic swimming activities, such as sprinting and fast-start manoeuvres during predator-prey interactions, has been little studied in air-breathing fishes. Some species practise air breathing during recovery itself, while others prefer to increase aquatic respiration, possibly to promote branchial ion exchange to restore acid-base balance, and to remain quiescent and avoid being visible to predators. Overall, the diversity of air-breathing fishes is reflected in their swimming physiology as well, and further research is needed to increase the understanding of the differences and the mechanisms through which air breathing is controlled and used during exercise.

  13. Swimming overuse injuries associated with triathlon training.

    Science.gov (United States)

    Bales, James; Bales, Karrn

    2012-12-01

    Most triathlon overuse injuries occur due to the running and cycling aspects of the sport. By nature of swimming being a non-weight-bearing sport, triathletes have a tendency to use swimming for rehabilitation and recovery. Swimming has a significantly lower injury rate than the other 2 disciplines in a triathlon. Most triathletes use the freestyle stroke, because it is typically the first stroke learned, it is for many the fastest stroke, and by lifting the head the freestyle stroke allows triathletes to sight their direction, which is important in open water swimming. During the freestyle stroke, the shoulder undergoes repetitive overhead motion, and shoulder pain is the most common and well-documented site of musculoskeletal pain in competitive swimmers. It is felt that the pathologic process is attributable to repetitive overhead motion causing microtrauma in the shoulder from either mechanical impingement or generalized laxity or both. Without sufficient rest and recovery, the development of inflammation and pain may result. Depending on the age of the triathlete and the exact etiology of the shoulder pain, treatment options range from nonsurgical to surgical in nature.

  14. The Effect of Pregnant Rat Swimming on Hypoxia-Inducible Factor-1α Levels of Neonatal Lung

    Directory of Open Access Journals (Sweden)

    Hajizade A

    2012-03-01

    Full Text Available Background: Uterine environment and fetal period can profoundly affect health of the neonat. Hypoxia-inducible factor-1α (HIF-1α is a transcription factor that regulates cellular stress responses and its activity is essential in both embryogenesis and postnatal life. The aim of the present study was to investigate the effects of maternal swimming on rat Pups' HIF-1α levels as a key regulator of oxygen in lungs.Methods: Sixteen female Wistar rats weighing 180- 200 grams were acclimated to a new environment consisting of equal light-darkness cycle and ad lib access to chow and adapted to the stress caused by water for two weeks. The rats were divided into two swimming and control groups. Swimming training began on the first day of pregnancy in a pool and continued for 3 weeks (1 h/day, 5 days/wk. Pups' lungs were removed two days after birth and their HIF-1α concentration was determined with enzyme-linked immunosorbent assay (ELISA. Statistical analysis of the data was done using independent t-test. A p-value smaller than 0.05 was considered statistically significant. Results: Swimming lead to a significant (P<0.001 increase in the Pups' lung HIF-1α levels compared with the control group. Although 3-wk period of swimming training, showed no significant increase in weight and also lung weight of newborns. Thus it can be concluded that swimming endurance training in pregnancy, can be considered as appropriate alternative in order to embryos development. Conclusion: Our research suggests that HIF-1α level is an essential element for the development of the lungs of embryos. Moreover, further studies on the lung HIF-1α levels at post-natal period with different modes of exercise will provide more clear insight into the mechanisms of the findings resulting from this study.

  15. Locomotor activity during the frenzy swim: analysing early swimming behaviour in hatchling sea turtles.

    Science.gov (United States)

    Pereira, Carla M; Booth, David T; Limpus, Colin J

    2011-12-01

    Swimming effort of hatchling sea turtles varies across species. In this study we analysed how swim thrust is produced in terms of power stroke rate, mean maximum thrust per power stroke and percentage of time spent power stroking throughout the first 18 h of swimming after entering the water, in both loggerhead and flatback turtle hatchlings and compared this with previous data from green turtle hatchlings. Loggerhead and green turtle hatchlings had similar power stroke rates and percentage of time spent power stroking throughout the trial, although mean maximum thrust was always significantly higher in green hatchlings, making them the most vigorous swimmers in our three-species comparison. Flatback hatchlings, however, were different from the other two species, with overall lower values in all three swimming variables. Their swimming effort dropped significantly during the first 2 h and kept decreasing significantly until the end of the trial at 18 h. These results support the hypothesis that ecological factors mould the swimming behaviour of hatchling sea turtles, with predator pressure being important in determining the strategy used to swim offshore. Loggerhead and green turtle hatchlings seem to adopt an intensely vigorous and energetically costly frenzy swim that would quickly take them offshore into the open ocean in order to reduce their exposure to near-shore aquatic predators. Flatback hatchlings, however, are restricted in geographic distribution and remain within the continental shelf region where predator pressure is probably relatively constant. For this reason, flatback hatchlings might use only part of their energy reserves during a less vigorous frenzy phase, with lower overall energy expenditure during the first day compared with loggerhead and green turtle hatchlings.

  16. Experimental Study on the Thermal Stratification in a Pool Boiling with a Horizontal Heat Source

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Seok; Ryu, Sung Uk; Euh, Dong-Jin; Song, Chul-Hwa [KAERI, Daejeon (Korea, Republic of)

    2015-05-15

    Thermal stratification is formed in horizontal fluid layers with different temperatures, where the warmer fluid layers are situated above the cooler fluid layers. Thermal stratification phenomena are common in pool type reactor systems, such as the liquid-salt cooled advanced high temperature reactor (AHTR) and liquid-metal cooled fast reactor systems such as the sodium fast reactor (SFR). Thermal stratification is increasingly encountered in large pools that are being used as heat sinks in the new generation of advanced reactors. The small-scale pool test was conducted to investigate the thermal stratification phenomena that occurred during the heat-up of a water in a pool. Because turbulence and boiling models affect the natural convection significantly, it is important to obtain local information regarding the fluid velocity and void distribution to determine the relevant physical models. To understand the flow phenomena inside a pool, a non-intrusive technique is adopted to measure the flow velocity field. In this study, the 2D particle image velocimetry (PIV) measurement technique is used to determine the fluid velocity vector field of single- and/or two-phase natural convection flow and thermal stratification in a pool. Detailed velocity measurements using the 2D PIV measurement technique were conducted to investigate single- and/or two-phase natural convection flow and thermal stratification in a pool boiling. In this study, the two-dimensional velocity vector fields as the water temperature increased were experimentally acquired in a pool that contained a horizontal heater rod. The experimental results indicate a large natural convection flow at the region above the heater rod and thermal stratification at the region below the heater rod. The flow of the opposite direction to each other was shown in the region between the heater rod and the thermal boundary layer. This flow pattern will contribute to maintain the thermal stratification and retard the water

  17. Present state of the liner of the reactor; Estado actual del liner del reactor

    Energy Technology Data Exchange (ETDEWEB)

    Aguilar H, F.; Raya A, R.; Mazon R, R. [ININ, 52045 Ocoyoacac, Estado de Mexico (Mexico)

    2001-07-15

    When being presented to work the operation personnel of the reactor, on Monday January 10, 1983, they noticed that the reactor pool was overflowing of water and the floor of the room was partially flooded. The personnel proceeded to revise the feedwater systems to the pool, the Emergency Cooling System of the core and that of Water of Reinstatement, was found that the passing valve of this last it was lightly open. It was discovered that the water that was flooded in the floor of the room it came from the relief valves of the ports TW-1 and RW-2 and of three glides that were in the Thermal Column area. It was proceeded to lower the one level of water of the pool to their normal position and it was clean the water flooded in the salts. (Author)

  18. Swimming fluctuations of micro-organisms due to heterogeneous microstructure

    Science.gov (United States)

    Jabbarzadeh, Mehdi; Hyon, YunKyong; Fu, Henry C.

    2014-10-01

    Swimming microorganisms in biological complex fluids may be greatly influenced by heterogeneous media and microstructure with length scales comparable to the organisms. A fundamental effect of swimming in a heterogeneous rather than homogeneous medium is that variations in local environments lead to swimming velocity fluctuations. Here we examine long-range hydrodynamic contributions to these fluctuations using a Najafi-Golestanian swimmer near spherical and filamentous obstacles. We find that forces on microstructures determine changes in swimming speed. For macroscopically isotropic networks, we also show how the variance of the fluctuations in swimming speeds are related to density and orientational correlations in the medium.

  19. Temperature dependent fission product removal efficiency due to pool scrubbing

    Energy Technology Data Exchange (ETDEWEB)

    Uchida, Shunsuke, E-mail: suchida@iae.or.jp [Institute of Applied Energy, 1-14-2, Nishi-Shimbashi, Minato-ku, Tokyo 105-0003 (Japan); Itoh, Ayumi; Naitoh, Masanori; Okada, Hidetoshi; Suzuki, Hiroyuki [Institute of Applied Energy, 1-14-2, Nishi-Shimbashi, Minato-ku, Tokyo 105-0003 (Japan); Hanamoto, Yukio [KAKEN, Inc., 1044, Hori-machi, Mito 310-0903 (Japan); Osakabe, Masahiro [Tokyo University of Marine Science & Technology, Koutou-ku, Tokyo 135-8533 (Japan); Fujikawa, Masahiro [Japan Broadcasting Corporation, 2-2-1, Jinnan, Shibuya-ku, Tokyo 150-8001 (Japan)

    2016-03-15

    Highlights: • Pool temperature effects on the FP removal were not clearly concluded in the previous publications. • It was confirmed that the removal efficiency decreased with temperature around the boiling point. • A modified empirical formula for FP removal was proposed as a function of sub-cooling temperature. • DF could be predicted with an accuracy within a factor of 2 with the proposed formula. - Abstract: The wet-well of boiling water reactors plays important roles not only to suppress the pressure in the primary containment vessel due to steam scrubbing effects during severe accidents but also to mitigate release of radioactive fission products (FP), aerosols and particulates, into the environment. The effects of steam scrubbing in the wet-well on FP removal have been well studied and reported by changing major parameters determining the removal efficiencies, e.g., aerosol diameters, submergence (depth of scrubbing nozzles) and steam/non-condensable gas volume fraction. Unfortunately, the effects of pool temperature on the FP removal were not clearly concluded in the previous publications, though it would be easily expected that boiling in the pool resulted in reduced aerosol removal efficiency. In order to determine the temperature effects on FP removal efficiency, amounts of cesium in aerosols released from scrubbing pool were measured by changing pool temperature in mini and medium scale scrubbing experiments, and then, it was confirmed that the removal efficiency clearly decreased with temperature around the boiling point. Then, a modified empirical formula to express the FP removal around the boiling point temperature was proposed as a function of sub-cooling temperature by applying the effective steam volume fraction, which was designated as the volume ratio of condensed steam in the pool versus the sum of input steam and non-condensable gas. By comparing the measured removal efficiency with the calculated, it was validated that the

  20. Optimal swimming strategies in mate searching pelagic copepods

    DEFF Research Database (Denmark)

    Kiørboe, Thomas

    2008-01-01

    Male copepods must swim to find females, but swimming increases the risk of meeting predators and is expensive in terms of energy expenditure. Here I address the trade-offs between gains and risks and the question of how much and how fast to swim using simple models that optimise the number...... of lifetime mate encounters. Radically different swimming strategies are predicted for different feeding behaviours, and these predictions are tested experimentally using representative species. In general, male swimming speeds and the difference in swimming speeds between the genders are predicted...... and observed to increase with increasing conflict between mate searching and feeding. It is high in ambush feeders, where searching (swimming) and feeding are mutually exclusive and low in species, where the matured males do not feed at all. Ambush feeding males alternate between stationary ambush feeding...

  1. Favourable impact of regular swimming in young people with haemophilia: experience derived from 'Desafio del Caribe' project.

    Science.gov (United States)

    Boadas, A; Osorio, M; Gibraltar, A; Rosas, M M; Berges, A; Herrera, E; Gadea, S; Gutiérrez, M Á; Salazar, F; Ruiz-Sáez, A

    2015-01-01

    Swimming is beneficial for persons with haemophilia (PWH) providing good maintenance of the cardiovascular and musculoskeletal system and improving many psychological characteristics. In the Desafío del Caribe Project, young PWH from Venezuela and Mexico took part in an open water competition in the Gulf of Mexico under a multidisciplinary team supervision. Eight severe haemophilia A, two moderate haemophilia A, one severe haemophilia B and two moderate haemophilia B subjects were included. Haematological, musculoskeletal and psychological evaluations were carried out before and during training for the competition. Training program included physical exercise routines and swimming practices that alternated between pools and open water. Swimmers had coverage with factor concentrates before pool and open water trainings. In physiatric evaluations, the Hemophilia Joint Health Score (HJHS) was used. The objective of the psychology area was to analyse self-esteem, precompetition anxiety, coping mechanisms and relaxation levels. The need of factor prophylaxis before intense trainings was confirmed. In the musculoskeletal system a decrease of elbow pain as well as an increase of muscle strength in the ankles were observed. In the psychological area significant differences between the first and second test in self-esteem levels, cognitive anxiety and group cohesion were found. PWH must be provided with orientation and encouragement to practice swimming regularly. High competition exercise must be supervised by a multidisciplinary team which must evaluate the pros and cons of the activity to make relevant recommendations.

  2. Synaptic vesicle pools and dynamics.

    Science.gov (United States)

    Alabi, AbdulRasheed A; Tsien, Richard W

    2012-08-01

    Synaptic vesicles release neurotransmitter at chemical synapses, thus initiating the flow of information in neural networks. To achieve this, vesicles undergo a dynamic cycle of fusion and retrieval to maintain the structural and functional integrity of the presynaptic terminals in which they reside. Moreover, compelling evidence indicates these vesicles differ in their availability for release and mobilization in response to stimuli, prompting classification into at least three different functional pools. Ongoing studies of the molecular and cellular bases for this heterogeneity attempt to link structure to physiology and clarify how regulation of vesicle pools influences synaptic strength and presynaptic plasticity. We discuss prevailing perspectives on vesicle pools, the role they play in shaping synaptic transmission, and the open questions that challenge current understanding.

  3. Patent pools: Intellectual property rights and competition

    NARCIS (Netherlands)

    Rodriguez, V.

    2010-01-01

    Patent pools do not correct all problems associated with patent thickets. In this respect, patent pools might not stop the outsider problem from striking pools. Moreover, patent pools can be expensive to negotiate, can exclude patent holders with smaller numbers of patents or enable a group of major

  4. Summary of Research on Interactive Safety Analysis Program of Pool Type SFR

    Institute of Scientific and Technical Information of China (English)

    2011-01-01

    The aim of the project was to develop an interactive safety analysis program of pool type sodium cooled fast reactors (SFR), based on a French system code OASIS. The function and physical model of the program should be verified by the application on CEFR design.

  5. Numerical analysis on pool boiling using user defined function

    Energy Technology Data Exchange (ETDEWEB)

    Ryu, Sung Uk; Jeon, Byong Guk; Kim, Seok; Euh, Dong-Jin [Korea Atomic Energy Research Institute, Daejeon (Korea, Republic of)

    2015-10-15

    PAFS (passive auxiliary feedwater system) adopted in the APR+ (Advanced Power Reactor Plus) of Korea is one such application. When PAFS is activated with an actuation signal, steam from the steam generator passes through heat exchanger tubes submerged in a water tank of the PAFS. Outside these heat exchanger tubes, nucleate boiling phenomena appears. In the present work, a numerical study is reported on three-dimensional transient state pool boiling of water having an immersed heat source. The velocity vector fields during the decrease in the water level are numerically investigated in a pool, and the accuracy of the results is checked by comparing the experimental results conducted using the PIV techniques by Kim et al. These numerical results can be used as basic research data for an analysis and prediction of the natural circulation phenomena in the cooling tank of the passive safety system in a nuclear power plant.

  6. Biomechanical analysis of the swim-start: a review.

    Science.gov (United States)

    Vantorre, Julien; Chollet, Didier; Seifert, Ludovic

    2014-05-01

    This review updates the swim-start state of the art from a biomechanical standpoint. We review the contribution of the swim-start to overall swimming performance, the effects of various swim-start strategies, and skill effects across the range of swim-start strategies identified in the literature. The main objective is to determine the techniques to focus on in swimming training in the contemporary context of the sport. The phases leading to key temporal events of the swim-start, like water entry, require adaptations to the swimmer's chosen technique over the course of a performance; we thus define the swim-start as the moment when preparation for take-off begins to the moment when the swimming pattern begins. A secondary objective is to determine the role of adaptive variability as it emerges during the swim-start. Variability is contextualized as having a functional role and operating across multiple levels of analysis: inter-subject (expert versus non-expert), inter-trial or intra-subject (through repetitions of the same movement), and inter-preference (preferred versus non-preferred technique). Regarding skill effects, we assume that swim-start expertise is distinct from swim stroke expertise. Highly skilled swim-starts are distinguished in terms of several factors: reaction time from the start signal to the impulse on the block, including the control and regulation of foot force and foot orientation during take-off; appropriate amount of glide time before leg kicking commences; effective transition from leg kicking to break-out of full swimming with arm stroking; overall maximal leg and arm propulsion and minimal water resistance; and minimized energy expenditure through streamlined body position. Swimmers who are less expert at the swim-start spend more time in this phase and would benefit from training designed to reduce: (i) the time between reaction to the start signal and impulse on the block, and (ii) the time in transition (i.e., between gliding and leg

  7. Dynamic simulation of accidental closure of intermediate heat exchanger isolation valve in a pool type LMFBR

    Energy Technology Data Exchange (ETDEWEB)

    Natesan, K., E-mail: natesan@igcar.gov.in [Reactor Engineering Group, Indira Gandhi Centre for Atomic Research, Kalpakkam (India); Kasinathan, N.; Velusamy, K.; Selvaraj, P.; Chellapandi, P.; Chetal, S.C. [Reactor Engineering Group, Indira Gandhi Centre for Atomic Research, Kalpakkam (India)

    2011-04-15

    Research highlights: > Thermal hydraulic analysis closure of sleeve valve in the primary circuit of FBR is discussed. > Numerical modeling of hydraulics in the primary and secondary sodium circuits is presented. > Aspects related to event management are discussed. - Abstract: In a pool type liquid metal cooled fast breeder reactor (LMFBR), core and other internals such as pumps, heat exchangers are immersed in a pool of sodium. Heat exchange from primary sodium circuit (pool) to secondary sodium circuit (loop) is through four intermediate heat exchangers (IHX) immersed in primary sodium pool. Each IHX is provided with a sleeve valve at its primary sodium inlet window for the purpose of isolating the shell side of IHX from the sodium pool. With such a provision, an inadvertent partial or complete closure of a sleeve valve of one of the IHX during normal operation of the reactor has been considered as a design basis event for the reactor. One dimensional transient thermal hydraulic models of the primary and secondary sodium circuits have been developed to study the thermal hydraulic consequences of such an event. The main areas of concern in the plant and the availability of safety parameters for the detection of the event have been evaluated.

  8. One-Dimensional Analysis of Thermal Stratification in AHTR and SFR Coolant Pools

    Energy Technology Data Exchange (ETDEWEB)

    Haihua Zhao; Per F. Peterson

    2007-10-01

    Thermal stratification phenomena are very common in pool type reactor systems, such as the liquid-salt cooled Advanced High Temperature Reactor (AHTR) and liquid-metal cooled fast reactor systems such as the Sodium Fast Reactor (SFR). It is important to accurately predict the temperature and density distributions both for design optimation and accident analysis. Current major reactor system analysis codes such as RELAP5 (for LWR’s, and recently extended to analyze high temperature reactors), TRAC (for LWR’s), and SASSYS (for liquid metal fast reactors) only provide lumped-volume based models which can only give very approximate results and can only handle simple cases with one mixing source. While 2-D or 3-D CFD methods can be used to analyze simple configurations, these methods require very fine grid resolution to resolve thin substructures such as jets and wall boundaries, yet such fine grid resolution is difficult or impossible to provide for studying the reactor response to transients due to computational expense. Therefore, new methods are needed to support design optimization and safety analysis of Generation IV pool type reactor systems. Previous scaling has shown that stratified mixing processes in large stably stratified enclosures can be described using one-dimensional differential equations, with the vertical transport by free and wall jets modeled using standard integral techniques. This allows very large reductions in computational effort compared to three-dimensional numerical modeling of turbulent mixing in large enclosures. The BMIX++ (Berkeley mechanistic MIXing code in C++) code was originally developed at UC Berkeley to implement such ideas. This code solves mixing and heat transfer problems in stably stratified enclosures. The code uses a Lagrangian approach to solve 1-D transient governing equations for the ambient fluid and uses analytical or 1-D integral models to compute substructures. By including liquid salt properties, BMIX++ code is

  9. Comparison of swim recovery and muscle stimulation on lactate removal after sprint swimming.

    Science.gov (United States)

    Neric, Francis B; Beam, William C; Brown, Lee E; Wiersma, Lenny D

    2009-12-01

    Competitive swimming requires multiple bouts of high-intensity exercise, leading to elevated blood lactate. Active exercise recovery has been shown to lower lactate faster than passive resting recovery but may not always be practical. An alternative treatment, electrical muscle stimulation, may have benefits similar to active recovery in lowering blood lactate but to date is unstudied. Therefore, this study compared submaximal swimming and electrical muscle stimulation in reducing blood lactate after sprint swimming. Thirty competitive swimmers (19 men and 11 women) participated in the study. Each subject completed 3 testing sessions consisting of a warm-up swim, a 200-yard maximal frontcrawl sprint, and 1 of 3 20-minute recovery treatments administered in random order. The recovery treatments consisted of a passive resting recovery, a submaximal swimming recovery, or electrical muscle stimulation. Blood lactate was tested at baseline, after the 200-yard sprint, and after 10 and 20 minutes of recovery. A significant interaction (p swimming recovery were significantly lower at 10 minutes (3.50 +/- 1.57 mmol.L-1) and 20 minutes (1.60 +/- 0.57 mmol.L-1) of recovery than either of the other 2 treatments. Electrical muscle stimulation led to a lower mean blood lactate (3.12 +/- 1.41 mmol.L-1) after 20 minutes of recovery compared with passive rest (4.11 +/- 1.35 mmol.L-1). Submaximal swimming proved to be most effective at lowering blood lactate, but electrical muscle stimulation also reduced blood lactate 20 minutes postexercise significantly better than resting passive recovery. Electrical muscle stimulation shows promise as an alternate recovery treatment for the purpose of lowering blood lactate.

  10. A Correlational Analysis of Tethered Swimming, Swim Sprint Performance and Dry-land Power Assessments.

    Science.gov (United States)

    Loturco, I; Barbosa, A C; Nocentini, R K; Pereira, L A; Kobal, R; Kitamura, K; Abad, C C C; Figueiredo, P; Nakamura, F Y

    2016-03-01

    Swimmers are often tested on both dry-land and in swimming exercises. The aim of this study was to test the relationships between dry-land, tethered force-time curve parameters and swimming performances in distances up to 200 m. 10 young male high-level swimmers were assessed using the maximal isometric bench-press and quarter-squat, mean propulsive power in jump-squat, squat and countermovement jumps (dry-land assessments), peak force, average force, rate of force development (RFD) and impulse (tethered swimming) and swimming times. Pearson product-moment correlations were calculated among the variables. Peak force and average force were very largely correlated with the 50- and 100-m swimming performances (r=- 0.82 and -0.74, respectively). Average force was very-largely/largely correlated with the 50- and 100-m performances (r=- 0.85 and -0.67, respectively). RFD and impulse were very-largely correlated with the 50-m time (r=- 0.72 and -0.76, respectively). Tethered swimming parameters were largely correlated (r=0.65 to 0.72) with mean propulsive power in jump-squat, squat-jump and countermovement jumps. Finally, mean propulsive power in jump-squat was largely correlated (r=- 0.70) with 50-m performance. Due to the significant correlations between dry-land assessments and tethered/actual swimming, coaches are encouraged to implement strategies able to increase leg power in sprint swimmers.

  11. Modeling vertical loads in pools resulting from fluid injection. [BWR

    Energy Technology Data Exchange (ETDEWEB)

    Lai, W.; McCauley, E.W.

    1978-06-15

    Table-top model experiments were performed to investigate pressure suppression pool dynamics effects due to a postulated loss-of-coolant accident (LOCA) for the Peachbottom Mark I boiling water reactor containment system. The results guided subsequent conduct of experiments in the /sup 1///sub 5/-scale facility and provided new insight into the vertical load function (VLF). Model experiments show an oscillatory VLF with the download typically double-spiked followed by a more gradual sinusoidal upload. The load function contains a high frequency oscillation superimposed on a low frequency one; evidence from measurements indicates that the oscillations are initiated by fluid dynamics phenomena.

  12. Flexible Conversion Ratio Fast Reactor Systems Evaluation

    Energy Technology Data Exchange (ETDEWEB)

    Neil Todreas; Pavel Hejzlar

    2008-06-30

    Conceptual designs of lead-cooled and liquid salt-cooled fast flexible conversion ratio reactors were developed. Both concepts have cores reated at 2400 MWt placed in a large-pool-type vessel with dual-free level, which also contains four intermediate heat exchanges coupling a primary coolant to a compact and efficient supercritical CO2 Brayton cycle power conversion system. Decay heat is removed passively using an enhanced Reactor Vessel Auxiliary Cooling System and a Passive Secondary Auxiliary Cooling System. The most important findings were that (1) it is feasible to design the lead-cooled and salt-cooled reactor with the flexible conversion ratio (CR) in the range of CR=0 and CR=1 n a manner that achieves inherent reactor shutdown in unprotected accidents, (2) the salt-cooled reactor requires Lithium thermal Expansion Modules to overcme the inherent salt coolant's large positive coolant temperature reactivity coefficient, (3) the preferable salt for fast spectrum high power density cores is NaCl-Kcl-MgCl2 as opposed to fluoride salts due to its better themal-hydraulic and neutronic characteristics, and (4) both reactor, but attain power density 3 times smaller than that of the sodium-cooled reactor.

  13. EP BICYCLE POOL - VIGNETTES 2002

    CERN Multimedia

    EP-SMI Help Desk

    2002-01-01

    The vignettes (insurance certificates) for 2002 become obligatory from 1 June. If you have a bicycle from the EP Pool, please bring it to the EP-SMI Help Desk (Building 124) on any working day up to 31 May between 8h.30 - 12h.00 or 13h.30 - 17h.30. EP-SMI Help Desk

  14. Male silver eels mature by swimming

    Directory of Open Access Journals (Sweden)

    Spaink Herman P

    2008-07-01

    Full Text Available Abstract Background If European silver eels are prevented from reproductive migration, they remain in a prepubertal stage by dopaminergic inhibition of pituitary activity. Because this inhibition is likely a requirement for an extended female growth stage, we tested if it is sex-specific by subjecting both sexes to stimulation by GnRHa (Gonadotropin-Releasing Hormone agonist – injection or 3-months swimming in seawater. Results In contrast to females, males showed a two- to three-fold higher LHβ (luteinising hormone β subunit – expression, a three- to five-fold higher GSI (Gonadosomatic index and induced spermatogenesis when compared with the untreated control group. Conclusion Dopaminergic inhibition is thus not effective in males and swimming results in natural maturation, probably via GnRH-release.

  15. Dynamics of swimming bacteria at complex interfaces

    CERN Document Server

    Lopez, Diego

    2014-01-01

    Flagellated bacteria exploiting helical propulsion are known to swim along circular trajectories near surfaces. Fluid dynamics predicts this circular motion to be clockwise (CW) above a rigid surface (when viewed from inside the fluid) and counter-clockwise (CCW) below a free surface. Recent experimental investigations showed that complex physicochemical processes at the nearby surface could lead to a change in the direction of rotation, both at solid surfaces absorbing slip-inducing polymers and interfaces covered with surfactants. Motivated by these results, we use a far-field hydrodynamic model to predict the kinematics of swimming near three types of interfaces: clean fluid-fluid interface, slipping rigid wall, and a fluid interface covered by incompressible surfactants. Representing the helical swimmer by a superposition of hydrodynamic singularities, we first show that in all cases the surfaces reorient the swimmer parallel to the surface and attract it, both of which are a consequence of the Stokes dip...

  16. Feeding, Swimming and Navigation of Colonial Microorganisms

    Science.gov (United States)

    Kirkegaard, Julius; Bouillant, Ambre; Marron, Alan; Leptos, Kyriacos; Goldstein, Raymond

    2016-11-01

    Animals are multicellular in nature, but evolved from unicellular organisms. In the closest relatives of animals, the choanoflagellates, the unicellular species Salpincgoeca rosetta has the ability to form colonies, resembling true multicellularity. In this work we use a combination of experiments, theory, and simulations to understand the physical differences that arise from feeding, swimming and navigating as colonies instead of as single cells. We show that the feeding efficiency decreases with colony size for distinct reasons in the small and large Péclet number limits, and we find that swimming as a colony changes the conventional active random walks of microorganism to stochastic helices, but that this does not hinder effective navigation towards chemoattractants.

  17. Swimming dynamics of the Lyme disease spirochete

    Science.gov (United States)

    Vig, Dhruv K.; Wolgemuth, Charles W.

    2013-01-01

    The Lyme disease spirochete, Borrelia burgdorferi, swims by undulating its cell body in the form of a traveling flat-wave, a process driven by rotating internal flagella. We study B. burgdorferi ’s swimming by treating the cell body and flagella as linearly elastic filaments. The dynamics of the cell are then determined from the balance between elastic and resistive forces and moments. We find that planar, traveling waves only exist when the flagella are effectively anchored at both ends of the bacterium and that these traveling flat-waves rotate as they undulate. The model predicts how the undulation frequency is related to the torque from the flagellar motors and how the stiffness of the cell body and flagella affect the undulations and morphology. PMID:23215618

  18. Analysis on the LODHR Event during Refueling Pool Operation

    Energy Technology Data Exchange (ETDEWEB)

    Cho, Dong Hyun; Huh, Jae Young; Lee, Gyu Cheon; Kim, Shin Whan [KEPCO E and C, Inc., Daejeon (Korea, Republic of)

    2015-10-15

    In this paper, the analysis is performed to evaluate the time to core uncovery and core damage as well as the time to core boiling. To analyze thermal hydraulic behaviors during refueling pool operation, RELAP5/MOD3.3 is used adopting the Henry-Fauske (H-F) critical flow model. The input modeling method adopts the method of SFP. The purpose of the analysis is to study the major results and T-H behaviors regarding to safety aspect during LODHR event at the refueling pool operation. In the present low power and shutdown (LPSD) probabilistic safety assessment (PSA) thermal hydraulic (T-H) analysis for dealing with various different plant operational states (POSs), the T-H analysis for the duration of refueling pool operation is omitted as it is considered less severe procedure during overhaul period for optimized power reactor 1000 (OPR1000). Instead only spent fuel pool analysis has been performed representing refueling operation mode (operation mode 6). However, in NUREG-1449, the NRC staff identified twelve technical issues that warrant further evaluation regarding shutdown and low power operation at U.S commercial nuclear power plants. One of issues identified for further evaluation is to evaluate the effect of PWR upper internals, that is, the PWR upper internals may inhibit water in the refueling pool from entering the core during a loss of decay heat removal event (LODHR). Per a commission paper (SECY-91-283) which reported progress to date on the evaluation, the NRC staff requested to address this safety issue by performing a quantitative and qualitative analysis. An analysis of LODHR was performed for advanced power reactor 1400 (APR1400) but it was focused to evaluate the initiation time of core boiling. As the results of the analysis for the LODHR during refueling pool operation, even though the core boiling is occurred in 15 minutes, there is enough water to cover the core and it prevents the core from damaging. The time is taken more than 4 days until the

  19. Passive swimming in viscous oscillatory flows

    Science.gov (United States)

    Jo, Ikhee; Huang, Yangyang; Zimmermann, Walter; Kanso, Eva

    2016-12-01

    Fluid-based locomotion at low Reynolds number is subject to the constraints of Purcell's scallop theorem: reciprocal shape kinematics identical under a time-reversal symmetry cannot cause locomotion. In particular, a single degree-of-freedom scallop undergoing opening and closing motions cannot swim. Most strategies for symmetry breaking and locomotion rely on direct control of the swimmer's shape kinematics. Less is known about indirect control via actuation of the fluid medium. To address how such indirect actuation strategies can lead to locomotion, we analyze a Λ -shaped model system analogous to Purcell's scallop but able to deform passively in oscillatory flows. Neutrally buoyant scallops undergo no net locomotion. We show that dense, elastic scallops can exhibit passive locomotion in zero-mean oscillatory flows. We examine the efficiency of swimming parallel to the background flow and analyze the stability of these motions. We observe transitions from stable to unstable swimming, including ordered transitions from fluttering to chaoticlike motions and tumbling. Our results demonstrate that flow oscillations can be used to passively actuate and control the motion of microswimmers, which may be relevant to applications such as surgical robots and cell sorting and manipulation in microfluidic devices.

  20. Swimming and feeding of mixotrophic biflagellates

    Science.gov (United States)

    Dölger, Julia; Nielsen, Lasse Tor; Kiørboe, Thomas; Andersen, Anders

    2017-01-01

    Many unicellular flagellates are mixotrophic and access resources through both photosynthesis and prey capture. Their fitness depends on those processes as well as on swimming and predator avoidance. How does the flagellar arrangement and beat pattern of the flagellate affect swimming speed, predation risk due to flow-sensing predators, and prey capture? Here, we describe measured flows around two species of mixotrophic, biflagellated haptophytes with qualitatively different flagellar arrangements and beat patterns. We model the near cell flows using two symmetrically arranged point forces with variable position next to a no-slip sphere. Utilizing the observations and the model we find that puller force arrangements favour feeding, whereas equatorial force arrangements favour fast and quiet swimming. We determine the capture rates of both passive and motile prey, and we show that the flow facilitates transport of captured prey along the haptonema structure. We argue that prey capture alone cannot fulfil the energy needs of the observed species, and that the mixotrophic life strategy is essential for survival.

  1. Do resonating bells increase jellyfish swimming performance?

    Science.gov (United States)

    Hoover, Alexander; Miller, Laura

    2013-11-01

    A current question in swimming and flight is whether or not driving flexible appendages at their resonant frequency results in faster or more efficient locomotion. It has been suggested that jellyfish swim faster and/or more efficiently when the bell is driven at its resonant frequency. Previous work has modeled the jellyfish bell as a damped harmonic oscillator, and this simplified model suggests that work done by the bell is maximized when force is applied at the resonant frequency of the bell. We extend the idea of resonance phenomena of the jellyfish bell to a fluid structure interaction framework using the immersed boundary method. We first examine the effects of the bending stiffness of the bell on its resonant frequency. We then further our model with the inclusion of a ``muscular'' spring that connects the two sides of a 2D bell and drives it near its resonant frequency. We use this muscular spring to force the bell at varying frequencies and examine the work done by these springs and the resulting swimming speed. We finally augment our model with a flexible, passive bell margin to examine its role in propulsive efficiency.

  2. Desipramine restricts estral cycle oscillations in swimming.

    Science.gov (United States)

    Contreras, C M; Martínez-Mota, L; Saavedra, M

    1998-10-01

    1. Desipramine (DMI) is a tricyclic antidepressant which reduces the immobility in rats forced to swim; however, it is unknown whether estral cycle phases impinge on DMI actions on immobility in daily swimming tests during several weeks. 2. In female wistar rats, vaginal smears taken before testing defined four estral phases. Afterwards, the authors assessed the latency for the first period of immobility in five-min forced swim tests practiced on 21-day DMI (DMI group), 21-day washout saline given after a 21-day DMI treatment (washout-saline group), or non-treated rats (control group). 3. We observed a longer latency for the first period of immobility in proestrus-estrus from the control and washout-saline groups. The 21-day treatment with DMI (2.1 mg/kg i.p., once a day) significantly (p estral cycle phase. 4. It is concluded that proestrus-estrus relates to increased struggling behavior. DMI enhances struggling behavior independently of hormonal state.

  3. Swimming and feeding of mixotrophic biflagellates

    Science.gov (United States)

    Dölger, Julia; Nielsen, Lasse Tor; Kiørboe, Thomas; Andersen, Anders

    2017-01-01

    Many unicellular flagellates are mixotrophic and access resources through both photosynthesis and prey capture. Their fitness depends on those processes as well as on swimming and predator avoidance. How does the flagellar arrangement and beat pattern of the flagellate affect swimming speed, predation risk due to flow-sensing predators, and prey capture? Here, we describe measured flows around two species of mixotrophic, biflagellated haptophytes with qualitatively different flagellar arrangements and beat patterns. We model the near cell flows using two symmetrically arranged point forces with variable position next to a no-slip sphere. Utilizing the observations and the model we find that puller force arrangements favour feeding, whereas equatorial force arrangements favour fast and quiet swimming. We determine the capture rates of both passive and motile prey, and we show that the flow facilitates transport of captured prey along the haptonema structure. We argue that prey capture alone cannot fulfil the energy needs of the observed species, and that the mixotrophic life strategy is essential for survival. PMID:28054596

  4. Measurement of photon flux with a miniature gas ionization chamber in a Material Testing Reactor

    Energy Technology Data Exchange (ETDEWEB)

    Fourmentel, D., E-mail: damien.fourmentel@cea.fr [CEA, DEN, DER, Instrumentation Sensors and Dosimetry Laboratory, Cadarache, F-13108 St-Paul-Lez-Durance (France); Filliatre, P.; Villard, J.F.; Lyoussi, A. [CEA, DEN, DER, Instrumentation Sensors and Dosimetry Laboratory, Cadarache, F-13108 St-Paul-Lez-Durance (France); Reynard-Carette, C. [Aix-Marseille Université, LISA EA 4672, cedex 20, Marseille 13397 (France); Carcreff, H. [CEA, DEN, DRSN, Saclay, F-91191 Gif-sur-Yvette (France)

    2013-10-01

    Nuclear heating measurements in Material Testing Reactors (MTR) are crucial for the design of the experimental devices and the prediction of the temperature of the hosted samples. Nuclear heating in MTR materials (except fuel) is mainly due to the energy deposition by the photon flux. Therefore, the photon flux is a key input parameter for the computer codes which simulate nuclear heating and temperature reached by samples/devices under irradiation. In the Jules Horowitz MTR under construction at the CEA Cadarache, the maximal expected nuclear heating levels will be about 15 to 18 W g{sup −1} and it will be necessary to assess this parameter with the best accuracy. An experiment was performed at the OSIRIS reactor to combine neutron flux, photon flux and nuclear heating measurements to improve the knowledge of the nuclear heating in MTR. There are few appropriate sensors for selective measurement of the photon flux in MTR even if studies and developments are ongoing. An experiment, called CARMEN-1, was conducted at the OSIRIS MTR and we used in particular a gas ionization chamber based on miniature fission chamber design to measure the photon flux. In this paper, we detail Monte-Carlo simulations to analyze the photon fluxes with ionization chamber measurements and we compare the photon flux calculations to the nuclear heating measurements. These results show a good accordance between photon flux measurements and nuclear heating measurement and allow improving the knowledge of these parameters.

  5. Emergency reactor core cooling water injection device for light water reactor

    Energy Technology Data Exchange (ETDEWEB)

    Oda, Junro.

    1994-05-13

    A reactor pressure vessel is immersed in pool water of a reactor container. A control valve is interposed to a water supplying pipelines connecting pool water and a pressure vessel. A valve actuation means for opening/closing the control valve comprises a lifting tank. The inner side of the lifting tank and the inner side of the pressure vessel are connected by a communication pipeline (a syphon pipe) at upper and lower two portions. The lifting tank and the control valve are connected by a link mechanism. When a water level in the pressure vessel is lowered, the water level in the lifting tank is lowered to the same level as that in the pressure vessel. This reduces the weight of the lifting tank, the lifting tank is raised, to open the control valve by way of a link mechanism. As a result, liquid phase in the pressure vessel is in communication with the pool water, and the pool water flows down into the pressure vessel to maintain the reactor core in a flooded state. (I.N.).

  6. Experiments of ECCS strainer blockage and debris settling in suppression pools

    Energy Technology Data Exchange (ETDEWEB)

    Hecker, G.E.; Johnson, A.B.; Murthy, P.; Padmanabhan

    1996-03-01

    If a rupture occurs in a nuclear power station pipe that leads to or from the reactor pressure vessel, the resultant Loss of Coolant Accident (LOCA) would initiate a chain of events involving complex flow phenomena. In a Boiling Water Reactor (BWR), the steam or liquid pipe break pressurizes the dry well, forcing the inert containment gases and steam through downcomers into the suppression pool, thoroughly mixing any particulates and pipe insulation debris carried with the gas flow to the pool. As the steam flow decreases, its unsteady condensation at the end of the downcomers (Condensation Oscillation and Chugging) produces continued water motion in the suppression pool and downcomers. During the blowdown event, high pressure and then low pressure pumps automatically start injecting water from the suppression pool into the reactor to keep its temperature under control. Proper functioning of this Emergency Core Cooling System (ECCS) is critical for the first 30 minutes or so, before operators have time to consider and align alternative sources of cooling water. A major concern for proper operation of the ECCS is the effect of fragmented insulation and plant particulates on the head loss at pump suction strainers. Sufficient loss could exceed the NPSH margin, causing cavitation with a resultant loss of pump capacity and longevity. The bead loss increases with the mass of debris accumulated on the pump strainers, which in turn is dependent on the debris concentration versus time in the suppression pool. This paper describes two sets of experiments that quantified the strainer head loss. One set of experiments considered the mixing and settling of fibrous insulation debris and fine iron oxide particles in the suppression pool during and after chugging. These tests used a reduced scale facility which duplicated the kinetic energy per unit water volume to define the concentration of the actual materials in the pool versus time.

  7. Building Restoration of Historic Pool in Bolesławiec: Assumptions, Design, Realization

    Science.gov (United States)

    Dudzik, Rafał

    2016-09-01

    The present elaboration describes realization of project task, entitled: "Retrieving old function in historic swimming pool, at 52 Zgorzelecka street in Bolesławiec", it has an influence with taking into consideration the most important problem on ultimate form of rebuilding, on base of present project done by the author of article, as being producer and planner at the same time. It emphasizes architectonic questions in text, concerning forming area, however, it omits solutions of numerous engineering problems (e. g. isolation and draining, etc.). Work project started at the end of 2010 and finished in February of year 2012. Object is in the course of final construction works.

  8. Operation experience of the Indonesian multipurpose research reactor RSG-GAS

    Energy Technology Data Exchange (ETDEWEB)

    Hastowo, Hudi; Tarigan, Alim [Multipurpose Reactor Center, National Nuclear Energy Agency of the Republic of Indonesia (PRSG-BATAN), Kawasan PUSPIPTEK Serpong, Tangerang (Indonesia)

    1999-08-01

    RSG-GAS is a multipurpose research reactor with nominal power of 30 MW, operated by BATAN since 1987. The reactor is an open pool type, cooled and moderated with light water, using the LEU-MTR fuel element in the form of U{sub 3}O{sub 8}-Al dispersion. Up to know, the reactor have been operated around 30,000 hours to serve the user. The reactor have been utilized to produce radioisotope, neutron beam experiments, irradiation of fuel element and its structural material, and reactor physics experiments. This report will explain in further detail concerning operational experience of this reactor, i.e. reactor operation data, reactor utilization, research program, technical problems and it solutions, plant modification and improvement, and development plan to enhance better reactor operation performance and its utilization. (author)

  9. 36 CFR 3.17 - What regulations apply to swimming areas and beaches?

    Science.gov (United States)

    2010-07-01

    ... swimming areas and beaches? 3.17 Section 3.17 Parks, Forests, and Public Property NATIONAL PARK SERVICE... and beaches? (a) The superintendent may designate areas as swimming areas or swimming beaches in... flotation devices, glass containers, kites, or incompatible activities in swimming areas or swimming...

  10. The Physiology and Mechanics of Undulatory Swimming: A Student Laboratory Exercise Using Medicinal Leeches

    Science.gov (United States)

    Ellerby, David J.

    2009-01-01

    The medicinal leech is a useful animal model for investigating undulatory swimming in the classroom. Unlike many swimming organisms, its swimming performance can be quantified without specialized equipment. A large blood meal alters swimming behavior in a way that can be used to generate a discussion of the hydrodynamics of swimming, muscle…

  11. Hybrid adsorptive membrane reactor

    Science.gov (United States)

    Tsotsis, Theodore T. (Inventor); Sahimi, Muhammad (Inventor); Fayyaz-Najafi, Babak (Inventor); Harale, Aadesh (Inventor); Park, Byoung-Gi (Inventor); Liu, Paul K. T. (Inventor)

    2011-01-01

    A hybrid adsorbent-membrane reactor in which the chemical reaction, membrane separation, and product adsorption are coupled. Also disclosed are a dual-reactor apparatus and a process using the reactor or the apparatus.

  12. D and DR Reactors

    Data.gov (United States)

    Federal Laboratory Consortium — The world's second full-scale nuclear reactor was the D Reactor at Hanford which was built in the early 1940's and went operational in December of 1944.D Reactor ran...

  13. Hybrid adsorptive membrane reactor

    Science.gov (United States)

    Tsotsis, Theodore T.; Sahimi, Muhammad; Fayyaz-Najafi, Babak; Harale, Aadesh; Park, Byoung-Gi; Liu, Paul K. T.

    2011-03-01

    A hybrid adsorbent-membrane reactor in which the chemical reaction, membrane separation, and product adsorption are coupled. Also disclosed are a dual-reactor apparatus and a process using the reactor or the apparatus.

  14. The fluid dynamics of swimming by jumping in copepods

    DEFF Research Database (Denmark)

    Jiang, Houshuo; Kiørboe, Thomas

    2011-01-01

    Copepods swim either continuously by vibrating their feeding appendages or erratically by repeatedly beating their swimming legs resulting in a series of small jumps. The two swimming modes generate different hydrodynamic disturbances and therefore expose the swimmers differently to rheotactic...... limited and temporally ephemeral owing to jump-impulsiveness and viscous decay. In contrast, continuous steady swimming generates two well-extended long-lasting momentum jets both in front of and behind the swimmer, as suggested by the well-known steady stresslet model. Based on the observed jump-swimming...... kinematics of a small copepod Oithona davisae, we further showed that jump-swimming produces a hydrodynamic disturbance with much smaller spatial extension and shorter temporal duration than that produced by a same-size copepod cruising steadily at the same average translating velocity. Hence, small copepods...

  15. Upward swimming of a sperm cell in shear flow

    Science.gov (United States)

    Omori, Toshihiro; Ishikawa, Takuji

    2016-03-01

    Mammalian sperm cells are required to swim over long distances, typically around 1000-fold their own length. They must orient themselves and maintain a swimming motion to reach the ovum, or egg cell. Although the mechanism of long-distance navigation is still unclear, one possible mechanism, rheotaxis, was reported recently. This work investigates the mechanism of the rheotaxis in detail by simulating the motions of a sperm cell in shear flow adjacent to a flat surface. A phase diagram was developed to show the sperm's swimming motion under different shear rates, and for varying flagellum waveform conditions. The results showed that, under shear flow, the sperm is able to hydrodynamically change its swimming direction, allowing it to swim upwards against the flow, which suggests that the upward swimming of sperm cells can be explained using fluid mechanics, and this can then be used to further understand physiology of sperm cell navigation.

  16. Upward swimming of a sperm cell in shear flow.

    Science.gov (United States)

    Omori, Toshihiro; Ishikawa, Takuji

    2016-03-01

    Mammalian sperm cells are required to swim over long distances, typically around 1000-fold their own length. They must orient themselves and maintain a swimming motion to reach the ovum, or egg cell. Although the mechanism of long-distance navigation is still unclear, one possible mechanism, rheotaxis, was reported recently. This work investigates the mechanism of the rheotaxis in detail by simulating the motions of a sperm cell in shear flow adjacent to a flat surface. A phase diagram was developed to show the sperm's swimming motion under different shear rates, and for varying flagellum waveform conditions. The results showed that, under shear flow, the sperm is able to hydrodynamically change its swimming direction, allowing it to swim upwards against the flow, which suggests that the upward swimming of sperm cells can be explained using fluid mechanics, and this can then be used to further understand physiology of sperm cell navigation.

  17. Swimming of Vorticella in two-dimensional confinements

    Science.gov (United States)

    Sotelo, Luz; Park, Young-Gil; Jung, Sunghwan; Ryu, Sangjin

    2015-03-01

    Vorticellais a ciliate observed in the stalked sessile form (trophont), which consists of an inverted bell-shaped cell body (zooid) and a slender stalk attaching the zooid to a substrate. Having circular cilia bands around the oral part, the stalkless zooid of Vorticella can serve as a model system for microorganism swimming. Here we present how the stalkess trophont zooid of Vorticella swims in two-dimensional confined geometries which are similar to the Hele-Shaw cell. Having harvested stalkless Vorticella zooids, we observed their swimming in water between two glass surfaces using video microscopy. Based on measured swimming trajectories and distributions of zooid orientation and swimming velocity, we analyzed how Vorticella's swimming mobility was influenced by the geometry constraints. Supported by First Award grant from Nebraska EPSCoR.

  18. Swimming speeds of filaments in nonlinearly viscoelastic fluids

    CERN Document Server

    Fu, Henry C; Powers, Thomas R; 10.1063/1.3086320

    2010-01-01

    Many microorganisms swim through gels and non-Newtonian fluids in their natural environments. In this paper, we focus on microorganisms which use flagella for propulsion. We address how swimming velocities are affected in nonlinearly viscoelastic fluids by examining the problem of an infinitely long cylinder with arbitrary beating motion in the Oldroyd-B fluid. We solve for the swimming velocity in the limit in which deflections of the cylinder from its straight configuration are small relative to the radius of the cylinder and the wavelength of the deflections; furthermore, the radius of the cylinder is small compared to the wavelength of deflections. We find that swimming velocities are diminished by nonlinear viscoelastic effects. We apply these results to examine what types of swimming motions can produce net translation in a nonlinear fluid, comparing to the Newtonian case, for which Purcell's "scallop" theorem describes how time-reversibility constrains which swimming motions are effective. We find that...

  19. Reactor pulse repeatability studies at the annular core research reactor

    Energy Technology Data Exchange (ETDEWEB)

    DePriest, K.R. [Applied Nuclear Technologies, Sandia National Laboratories, Mail Stop 1146, Post Office Box 5800, Albuquerque, NM 87185-1146 (United States); Trinh, T.Q. [Nuclear Facility Operations, Sandia National Laboratories, Mail Stop 0614, Post Office Box 5800, Albuquerque, NM 87185-1146 (United States); Luker, S. M. [Applied Nuclear Technologies, Sandia National Laboratories, Mail Stop 1146, Post Office Box 5800, Albuquerque, NM 87185-1146 (United States)

    2011-07-01

    The Annular Core Research Reactor (ACRR) at Sandia National Laboratories is a water-moderated pool-type reactor designed for testing many types of objects in the pulse and steady-state mode of operations. Personnel at Sandia began working to improve the repeatability of pulse operations for experimenters in the facility. The ACRR has a unique UO{sub 2}-BeO fuel that makes the task of producing repeatable pulses difficult with the current operating procedure. The ACRR produces a significant quantity of photoneutrons through the {sup 9}Be({gamma}, n){sup 8}Be reaction in the fuel elements. The photoneutrons are the result of the gammas produced during fission and in fission product decay, so their production is very much dependent on the reactor power history and changes throughout the day/week of experiments in the facility. Because the photoneutrons interfere with the delayed-critical measurements required for accurate pulse reactivity prediction, a new operating procedure was created. The photoneutron effects at delayed critical are minimized when using the modified procedure. In addition, the pulse element removal time is standardized for all pulse operations with the modified procedure, and this produces less variation in reactivity removal times. (authors)

  20. Examining Self-Training Procedures in Leisure Swimming

    OpenAIRE

    J. Potdevin, Francois; Normani, Clement; Pelayo, Patrick

    2013-01-01

    This study investigated contents of training sessions from 387 regular swimmers involved in a recreational workout without supervision. We did use multiple correspondences analysis in order to identify self-trained swimmers typology in a sample from a social networking website, focusing on swimming practice. Self-reported parameters (n = 12) were age, gender, practice frequency, supervision in physical activity experiment, main training target, main reason for swimming choice, swimming sessio...

  1. On the Swimming of \\textit{Dictyostelium} amoebae

    CERN Document Server

    Bae, Albert

    2010-01-01

    Traditionally, the primary mode for locomotion of amoeboid cells was thought to be crawling on a substrate. Recently, it has been experimentally shown that \\textit{Dictostelium} amoeba and neutrophils can also swim in a directed fashion. The mechanisms for amoeboid crawling and swimming were hypothesized to be similar. In this letter, we show that the shape changes generated by a crawling \\textit{D. discoideum} cell are consistent with swimming.

  2. The effect of gait on swimming in viscoelastic fluids

    CERN Document Server

    Elfring, Gwynn J

    2015-01-01

    In this paper, we give formulas for the swimming of simplified two-dimensional bodies in complex fluids using the reciprocal theorem. By way of these formulas we calculate the swimming velocity due to small-amplitude deformations on the simplest of these bodies, a two-dimensional sheet, to explore general conditions on the swimming gait under which the sheet may move faster, or slower, in a viscoelastic fluid compared to a Newtonian fluid.

  3. Determination of local boiling in light water reactors by correlation of the neutron noise; Determination de l'ebullition locale dans les reacteurs a eau legere par correlation du bruit neutronique

    Energy Technology Data Exchange (ETDEWEB)

    Zwingelstein, G. [Commissariat a l' Energie Atomique, Saclay (France). Centre d' Etudes Nucleaires

    1968-07-01

    The power limit of swimming-pool type reactors depends on the phenomenon of the appearance of burn-out. In order to determine this limit we have attempted to detect the local boiling which usually occurs before the burn out. Local boiling has been simulated by an electrically heated plate placed in the core of the reactor Siloette. The study of local boiling, which is based on the properties of the correlation functions for the neutron noise of detectors placed in the core, shows that a privileged frequency occurs in the power spectrum of the noise. It is intended in the future to determine the influence of various parameters on this characteristic frequency. (author) [French] La limitation de la puissance des reacteurs nucleaires de type piscine est due au phenomene d'apparition de 'burn out'. Pour determiner cette limitation, nous nous sommes proposes dans ce rapport de detecter l'ebullition locale qui apparait generalement avant le 'burn out'. L'ebullition locale a ete simulee par une plaque chauffee electriquement et placee dans le coeur du reacteur SILOETTE. L'etude de l'ebullition locale, qui est basee sur les proprietes des fonctions de correlation du bruit neutronique de detecteurs places clans le coeur, fait apparaitre une frequence privilegiee dans le spectre de puissance du bruit. On envisage dans l'avenir, de determiner l'influence des divers parametres sur cette frequence caracteristique. (auteur)

  4. The muon system of the Daya Bay Reactor antineutrino experiment

    Energy Technology Data Exchange (ETDEWEB)

    An, F.P. [Institute of Modern Physics, East China University of Science and Technology, Shanghai (China); Institute of High Energy Physics, Beijing (China); Balantekin, A.B. [University of Wisconsin, Madison, WI (United States); Band, H.R. [Department of Physics, Yale University, New Haven, CT (United States); University of Wisconsin, Madison, WI (United States); Beriguete, W.; Bishai, M. [Brookhaven National Laboratory, Upton, NY (United States); Blyth, S. [Department of Physics, National Taiwan University, Taipei (China); National United University, Miao-Li, Taiwan (China); Brown, R.E. [Brookhaven National Laboratory, Upton, NY (United States); Butorov, I. [Joint Institute for Nuclear Research, Dubna, Moscow Region (Russian Federation); Cao, G.F.; Cao, J. [Institute of High Energy Physics, Beijing (China); Carr, R. [California Institute of Technology, Pasadena, CA (United States); Chan, Y.L. [Chinese University of Hong Kong (Hong Kong); Chang, J.F. [Institute of High Energy Physics, Beijing (China); Chang, L. [Institute of Physics, National Chiao-Tung University, Hsinchu, Taiwan (China); Chang, Y. [National United University, Miao-Li, Taiwan (China); Chasman, C. [Brookhaven National Laboratory, Upton, NY (United States); Chen, H.S. [Institute of High Energy Physics, Beijing (China); Chen, H.Y. [Institute of Physics, National Chiao-Tung University, Hsinchu, Taiwan (China); Chen, Q.Y. [Shandong University, Jinan (China); Chen, S.J. [Nanjing University, Nanjing (China); and others

    2015-02-11

    The Daya Bay experiment consists of functionally identical antineutrino detectors immersed in pools of ultrapure water in three well-separated underground experimental halls near two nuclear reactor complexes. These pools serve both as shields against natural, low-energy radiation, and as water Cherenkov detectors that efficiently detect cosmic muons using arrays of photomultiplier tubes. Each pool is covered by a plane of resistive plate chambers as an additional means of detecting muons. Design, construction, operation, and performance of these muon detectors are described.

  5. Criticality safety of the ET-RR-1 new spent fuel storage pool

    Energy Technology Data Exchange (ETDEWEB)

    Massoud, E.; Sallam, O.H.; Amin, E

    2001-03-01

    A new ET-RR-1 spent fuel storage pool is now under construction on the reactor site at Inshass. In addition, the pool is designed to accommodate spent fuel of MTR type as well. Criticality safety of this pool for the different fuel types has been evaluated as a function of U{sup 235} loading. The effect of fuel element separation (rows and columns) on the eigenvalue has been studied. As a conservative assumption, the pool is assumed to be filled with fresh fuel. The eigenvalue considering a realistic degree of fuel burn-up was determined in order to determine the safety margin. The calculations have been carried out using the code packages of the National Center for Nuclear Safety and Radiation Control.

  6. A Consensual Linear Opinion Pool

    CERN Document Server

    Carvalho, Arthur

    2012-01-01

    We propose a pooling method to aggregate expert opinions. Intuitively, it works as if the experts were continuously updating their opinions in order to accommodate the expertise of others. Each updated opinion takes the form of a linear opinion pool, where the weight that an expert assigns to a peer's opinion is inversely related to the distance between their opinions. In other words, experts are assumed to prefer opinions that are close to their own opinions. We prove that such an updating process leads to consensus, i.e., the experts all converge towards the same opinion. Further, we show that if experts are rewarded using the quadratic scoring rule, then the above mentioned assumption follows naturally. We empirically demonstrate the efficacy of our method using real-world data.

  7. Swimming exercise: impact of aquatic exercise on cardiovascular health.

    Science.gov (United States)

    Tanaka, Hirofumi

    2009-01-01

    Swimming is an exercise modality that is highly suitable for health promotion and disease prevention, and is one of the most popular, most practiced and most recommended forms of physical activity. Yet little information is available concerning the influence of regular swimming on coronary heart disease (CHD). Exercise recommendations involving swimming have been generated primarily from unjustified extrapolation of the data from other modes of exercise (e.g. walking and cycling). Available evidence indicates that, similarly to other physically active adults, the CHD risk profile is more favourable in swimmers than in sedentary counterparts and that swim training results in the lowering of some CHD risk factors. However, the beneficial impact of regular swimming may be smaller than land-based exercises. In some cases, regular swimming does not appear to confer beneficial effects on some CHD risk factors. Moreover, swimming has not been associated with the reduced risks of developing CHD. Thus, extrapolation of research findings using land-based exercises into swimming cannot be justified, based on the available research. Clearly, more research is required to properly assess the effects of regular swimming on CHD risks in humans.

  8. Sustainability of common pool resources

    Science.gov (United States)

    Timilsina, Raja Rajendra; Kamijo, Yoshio

    2017-01-01

    Sustainability has become a key issue in managing natural resources together with growing concerns for capitalism, environmental and resource problems. We hypothesize that the ongoing modernization of competitive societies, which we refer to as “capitalism,” affects human nature for utilizing common pool resources, thus compromising sustainability. To test this hypothesis, we design and implement a set of dynamic common pool resource games and experiments in the following two types of Nepalese areas: (i) rural (non-capitalistic) and (ii) urban (capitalistic) areas. We find that a proportion of prosocial individuals in urban areas is lower than that in rural areas, and urban residents deplete resources more quickly than rural residents. The composition of proself and prosocial individuals in a group and the degree of capitalism are crucial in that an increase in prosocial members in a group and the rural dummy positively affect resource sustainability by 65% and 63%, respectively. Overall, this paper shows that when societies move toward more capitalistic environments, the sustainability of common pool resources tends to decrease with the changes in individual preferences, social norms, customs and views to others through human interactions. This result implies that individuals may be losing their coordination abilities for social dilemmas of resource sustainability in capitalistic societies. PMID:28212426

  9. Pool power control in remelting systems

    Science.gov (United States)

    Williamson, Rodney L.; Melgaard, David K.; Beaman, Joseph J.

    2011-12-13

    An apparatus for and method of controlling a remelting furnace comprising adjusting current supplied to an electrode based upon a predetermined pool power reference value and adjusting the electrode drive speed based upon the predetermined pool power reference value.

  10. The warm pool in the Indian Ocean

    Digital Repository Service at National Institute of Oceanography (India)

    Vinayachandran, P.N.; Shetye, S.R.

    The structure of the warm pool (region with temperature greater than 28 degrees C) in the equatorial Indian Ocean is examined and compared with its counterpart in the Pacific Ocean using the climatology of Levitus. Though the Pacific warm pool...

  11. Effects of intraspecific variation in reproductive traits, pectoral fin use and burst swimming on metabolic rates and swimming performance in the Trinidadian guppy (Poecilia reticulata).

    Science.gov (United States)

    Svendsen, Jon C; Banet, Amanda I; Christensen, Rune H B; Steffensen, John F; Aarestrup, Kim

    2013-09-15

    There is considerable intraspecific variation in metabolic rates and locomotor performance in aquatic ectothermic vertebrates; however, the mechanistic basis remains poorly understood. Using pregnant Trinidadian guppies (Poecilia reticulata), a live-bearing teleost, we examined the effects of reproductive traits, pectoral fin use and burst-assisted swimming on swimming metabolic rate, standard metabolic rate (O2std) and prolonged swimming performance (Ucrit). Reproductive traits included reproductive allocation and pregnancy stage, the former defined as the mass of the reproductive tissues divided by the total body mass. Results showed that the metabolic rate increased curvilinearly with swimming speed. The slope of the relationship was used as an index of swimming cost. There was no evidence that reproductive traits correlated with swimming cost, O2std or Ucrit. In contrast, data revealed strong effects of pectoral fin use on swimming cost and Ucrit. Poecilia reticulata employed body-caudal fin (BCF) swimming at all tested swimming speeds; however, fish with a high simultaneous use of the pectoral fins exhibited increased swimming cost and decreased Ucrit. These data indicated that combining BCF swimming and pectoral fin movement over a wide speed range, presumably to support swimming stability and control, is an inefficient swimming behaviour. Finally, transition to burst-assisted swimming was associated with an increase in aerobic metabolic rate. Our study highlights factors other than swimming speed that affect swimming cost and suggests that intraspecific diversity in biomechanical performance, such as pectoral fin use, is an important source of variation in both locomotor cost and maximal performance.

  12. Reactor and method of operation

    Science.gov (United States)

    Wheeler, John A.

    1976-08-10

    A nuclear reactor having a flattened reactor activity curve across the reactor includes fuel extending over a lesser portion of the fuel channels in the central portion of the reactor than in the remainder of the reactor.

  13. Related activities on management of ageing of Dalat Research Reactor

    Energy Technology Data Exchange (ETDEWEB)

    Pham Van Lam [Reactor Dept., Nuclear Research Institute, Dalat (Viet Nam)

    1998-10-01

    The Dalat Nuclear Research Reactor (DNRR) is a pool type research reactor which was reconstructed in 1982 from the previous 250 kW TRIGA-MARK II reactor. The reactor core, the control and instrumentation system, the primary and secondary cooling systems as well as other associated systems were newly designed and installed. The renovated reactor reached its initial criticality in November 1983 and attained its nominal power of 500 kW in February 1984. Since then DNRR has been operated safely. Retained structures of the former reactor such as the reactor aluminum tank, the graphite reflector, the thermal column, the horizontal beam tubes and the radiation concrete shielding are 35 years old. During the recent years, in-service inspection has been carried out, the reactor control and instrumentation system were renovated due to ageing and obsolescence of its components, reactor general inspection and refurbishment were performed. Efforts are being made to cope with ageing of old reactor components to maintain safe operation of the DNRR. (author)

  14. 7 CFR 1032.7 - Pool plant.

    Science.gov (United States)

    2010-01-01

    ... 7 Agriculture 9 2010-01-01 2009-01-01 true Pool plant. 1032.7 Section 1032.7 Agriculture... Handling Definitions § 1032.7 Pool plant. Pool plant means a plant, unit of plants, or system of plants as specified in paragraphs (a) through (f) of this section, or a plant specified in paragraph (i) of...

  15. 7 CFR 1033.7 - Pool plant.

    Science.gov (United States)

    2010-01-01

    ... 7 Agriculture 9 2010-01-01 2009-01-01 true Pool plant. 1033.7 Section 1033.7 Agriculture... Handling Definitions § 1033.7 Pool plant. Pool plant means a plant, unit of plants, or system of plants as specified in paragraphs (a) through (f) of this section, or a plant specified in paragraph (j) of...

  16. 7 CFR 1124.7 - Pool plant.

    Science.gov (United States)

    2010-01-01

    ... 7 Agriculture 9 2010-01-01 2009-01-01 true Pool plant. 1124.7 Section 1124.7 Agriculture... Regulating Handling Definitions § 1124.7 Pool plant. Pool plant means a plant, unit of plants, or a system of plants as specified in paragraphs (a) through (f) of this section, but excluding a plant specified...

  17. 7 CFR 1126.7 - Pool plant.

    Science.gov (United States)

    2010-01-01

    ... 7 Agriculture 9 2010-01-01 2009-01-01 true Pool plant. 1126.7 Section 1126.7 Agriculture... Handling Definitions § 1126.7 Pool plant. Pool plant means a plant specified in paragraphs (a) through (d) of this section, a unit of plants as specified in paragraph (e) of this section, or a plant...

  18. 7 CFR 1131.7 - Pool plant.

    Science.gov (United States)

    2010-01-01

    ... 7 Agriculture 9 2010-01-01 2009-01-01 true Pool plant. 1131.7 Section 1131.7 Agriculture... Handling Definitions § 1131.7 Pool plant. Pool Plant means a plant or unit of plants specified in paragraphs (a) through (e) of this section, but excluding a plant specified in paragraph (g) of this...

  19. 7 CFR 1007.7 - Pool plant.

    Science.gov (United States)

    2010-01-01

    ... 7 Agriculture 9 2010-01-01 2009-01-01 true Pool plant. 1007.7 Section 1007.7 Agriculture... Handling Definitions § 1007.7 Pool plant. Pool plant means a plant specified in paragraphs (a) through (d) of this section, a unit of plants as specified in paragraph (e) of this section, or a plant...

  20. 7 CFR 1005.7 - Pool plant.

    Science.gov (United States)

    2010-01-01

    ... 7 Agriculture 9 2010-01-01 2009-01-01 true Pool plant. 1005.7 Section 1005.7 Agriculture... Handling Definitions § 1005.7 Pool plant. Pool plant means a plant specified in paragraphs (a) through (d) of this section, a unit of plants as specified in paragraph (e) of this section, or a plant...