Thermo-siphon Mock-up Test for the HANARO-CNS

Energy Technology Data Exchange (ETDEWEB)

Choi, Jungwoon; Lee, Kye Hong; Kim, Hark Rho; Kim, Youngki; Kim, Myong Seop; Wu, Sang Ik; Kim, Bong Su

2006-04-15

In order to moderate thermal neutrons into cold neutrons, the liquid hydrogen is selected as a moderator for the HANARO CNS. By the non-nuclear heat load and nuclear heat load induced from collision of gamma-ray, beta-ray, and thermal neutrons, the liquid hydrogen in the moderator cell evaporates and flows into the heat exchanger. This evaporated hydrogen gas is liquefied by the cryogenic helium supplied from the helium refrigeration system,, then flows back to the moderator cell. This is so-called two-phase thermo-siphon. The most important point in the stable thermo-siphon is to have the good balance between the cooling capacity of the HRS and the heat load on the moderator cell so as to maintain the stable two-phase liquid level in the moderator cell. Accordingly, for not only the experience of the cryogenic two-phase thermo-siphon but also setup of the operation procedure, the full-scaled mock-up test has been performed using the liquid hydrogen. Through the test, the stable thermo-siphon establishment is confirmed at the cold normal operation; furthermore, the detail design parameter is validated. On top of the normal operation procedure setup, the abnormal operation procedure is settled based on the understanding the abnormal pressure and temperature transient dynamics in the hydrogen system.

IMPACT OF SIPHONING ACTIVITY AND NATURALLY SUSPENDED PARTICLE LOAD ON MUSSEL KILL by PSEUDOMONAS FLUORESCENS

International Nuclear Information System (INIS)

Daniel Molloy

2003-01-01

Under this USDOE-NETL contract, the bacterium Pseudomonas fluorescens is being developed as a biocontrol agent for zebra mussels. The specific purpose of the contract is to identify biotic and abiotic factors that affect mussel kill. Ingestion of these bacteria by zebra mussels is required to achieve kill, and tests evaluating factors that relate to mussel feeding are contained in this report. Specifically the impact of the following two factors were investigated: (1) Mussel siphoning behavior--In nature, zebra mussels typically have their two shells spread apart and their inhalant siphon tube extended from between their shells for taking food particles into their mantle cavities (Fig. 1). Our tests indicated that there is a direct correlation between mussel siphoning activity and mussel mortality achieved by a bacterial treatment. Therefore, to encourage mussel feeding on bacteria, future pipe treatments within power plants should be carried out using procedures which minimize disturbance to mussel siphoning. 2. Naturally suspended particle loads--Since bacterial cells are lethal only if ingested by mussels, waters containing very high levels of naturally suspended particles might reduce the mortality that can be achieved by a bacterial treatment. If true, this inhibition might occur as a result of particle exclusion, i.e., there could be reduced ingestion of bacterial cells since they represent a reduced percentage of all particles ingested. Our tests indicated that a range of particle concentrations that might naturally exist in a turbid river did not inhibit mussel kill by the bacterial cells, but that an artificially high load of natural particles was capable of causing a reduction in kill. To be conservative, therefore, future pipe treatments should be timed to occur when intake waters have relatively low quantities of naturally suspended particulate matter

IMPACT OF SIPHONING ACTIVITY AND NATURALLY SUSPENDED PARTICLE LOAD ON MUSSEL KILL by PSEUDOMONAS FLUORESCENS

Energy Technology Data Exchange (ETDEWEB)

Daniel Molloy

2003-08-04

Under this USDOE-NETL contract, the bacterium Pseudomonas fluorescens is being developed as a biocontrol agent for zebra mussels. The specific purpose of the contract is to identify biotic and abiotic factors that affect mussel kill. Ingestion of these bacteria by zebra mussels is required to achieve kill, and tests evaluating factors that relate to mussel feeding are contained in this report. Specifically the impact of the following two factors were investigated: (1) Mussel siphoning behavior--In nature, zebra mussels typically have their two shells spread apart and their inhalant siphon tube extended from between their shells for taking food particles into their mantle cavities (Fig. 1). Our tests indicated that there is a direct correlation between mussel siphoning activity and mussel mortality achieved by a bacterial treatment. Therefore, to encourage mussel feeding on bacteria, future pipe treatments within power plants should be carried out using procedures which minimize disturbance to mussel siphoning. 2. Naturally suspended particle loads--Since bacterial cells are lethal only if ingested by mussels, waters containing very high levels of naturally suspended particles might reduce the mortality that can be achieved by a bacterial treatment. If true, this inhibition might occur as a result of particle exclusion, i.e., there could be reduced ingestion of bacterial cells since they represent a reduced percentage of all particles ingested. Our tests indicated that a range of particle concentrations that might naturally exist in a turbid river did not inhibit mussel kill by the bacterial cells, but that an artificially high load of natural particles was capable of causing a reduction in kill. To be conservative, therefore, future pipe treatments should be timed to occur when intake waters have relatively low quantities of naturally suspended particulate matter.

Establishing experimental model of human internal carotid artery siphon segment in canine common carotid artery

International Nuclear Information System (INIS)

Cui Xuee; Li Minghua; Wang Yongli; Cheng Yingsheng; Li Wenbin

2005-01-01

Objective: To study the feasibility of establishing experimental model of human internal carotid artery siphon segment in canine common carotid artery (CCA) by end-to-end anastomoses of one side common carotid artery segment with the other side common carotid artery. Methods: Surgical techniques were used to make siphon model in 8 canines. One side CCA was taken as the parent artery and anastomosing with the cut off contra-lateral CCA segment which has passed through within the S-shaped glass tube. Two weeks after the creation of models angiography showed the model siphons were patent. Results: Experimental models of human internal carotid artery siphon segment were successfully made in all 8 dogs. Conclusions: It is practically feasible to establish experimental canine common carotid artery models of siphon segment simulating human internal carotid artery. (authors)

Comparative studies on the histology and ultrastructure of the siphons of two species of Tellinidae (Mollusca: Bivalvia from Brazil

Directory of Open Access Journals (Sweden)

João E.V.V. Vitonis

2012-06-01

Full Text Available Despite the great importance of the siphons for infaunal bivalves, only a few studies have examined their tissues using histology techniques or scanning electron microscopy. In the present study, the siphons of Tellina lineata Turton, 1819 and Macoma biota Arruda & Domaneschi, 2005 were investigated. The siphon walls are composed by a series of muscle sheets of longitudinal ("L", circular ("C" and radial ("R" fibers, with a clear pattern common to both species: there is a main median longitudinal layer (Lm, and two peripheral circular layers, one inner (Ci and one outer (Co, near the epithelia. A median circular layer (Cm separates an internal (Lmi from an outer (Lmo median longitudinal layer. Further, the Co is split by a thin outer longitudinal layer (Lo, forming Coi and Coo layers, the former being obliquely oriented. Thin radial fibers (R delimit clear packages of Lmi and Lmo fibers. In each siphon, there are six longitudinal nerve cords, running within the Lmi layer, adjacent to the Cm. The inhalant and exhalant siphons of M. biota are very similar in structure, but the Lmo of the exhalant siphon is almost twice as thick as its Lmi, while in the inhalant siphon these layers have similar thicknesses; the Coi is very thick, especially in the exhalant siphon. The inhalant siphon of T. lineata is very similar to that of M. biota, differing only with respect to the thickness of the Coi, which in the former species is not as well developed as in the latter. The Lmo of the exhalant siphon of T. lineata is by far the most developed layer, with the Lmi represented only by uniseriate small cells; in the vicinities of the nerve cords, the Cm is split in two layers. The epithelia of both siphons of M. biota and T. lineata bear ciliated receptors, which were difficult to observe as they were frequently covered with mucus. It was possible to observe that cilia are present in both species, differing in length and in the number per receptor between the

A simplified approach for the computation of steady two-phase flow in inverted siphons.

Science.gov (United States)

Diogo, A Freire; Oliveira, Maria C

2016-01-15

Hydraulic, sanitary, and sulfide control conditions of inverted siphons, particularly in large wastewater systems, can be substantially improved by continuous air injection in the base of the inclined rising branch. This paper presents a simplified approach that was developed for the two-phase flow of the rising branch using the energy equation for a steady pipe flow, based on the average fluid fraction, observed slippage between phases, and isothermal assumption. As in a conventional siphon design, open channel steady uniform flow is assumed in inlet and outlet chambers, corresponding to the wastewater hydraulic characteristics in the upstream and downstream sewers, and the descending branch operates in steady uniform single-phase pipe flow. The proposed approach is tested and compared with data obtained in an experimental siphon setup with two plastic barrels of different diameters operating separately as in a single-barrel siphon. Although the formulations developed are very simple, the results show a good adjustment for the set of the parameters used and conditions tested and are promising mainly for sanitary siphons with relatively moderate heights of the ascending branch. Copyright © 2015 Elsevier Ltd. All rights reserved.

Characterization of a siphonal flow electro-coagulation reactor for the water de-pollution; Caracterisation d'un reacteur d'electrocoagulation a ecoulement siphoide pour la depollution des eaux

Energy Technology Data Exchange (ETDEWEB)

Deffontaines, B.; Deffontaines-Fourez, M.; Thivel, P.X. [Unversite du Littoral - Cote d' Opale, Centre Universitaire Descartes, Lab. d' Etude en Genie Industriel et Management Environnemental, 62 - Longuenesse (France)

2001-07-01

The aim of this study is the establishment of a global quantitative relation between the kinetic and the hydrodynamic of a siphonal flow reactor. First results of the application in dyeing effluents recycling illustrate the reactor performance on the MES abatement and the turbidity of the recycling waters in the production cycle. (A.L.B.)

TNX GeoSiphon Cell (TGSC-1) Phase II Single Cell Deployment/Demonstration Final Report

Energy Technology Data Exchange (ETDEWEB)

Phifer, M.A.

1999-04-15

This Phase II final report documents the Phase II testing conducted from June 18, 1998 through November 13, 1998, and it focuses on the application of the siphon technology as a sub-component of the overall GeoSiphon Cell technology. [Q-TPL-T-00004

Interventional therapy of traumatic pseudoaneurysms in internal carotid artery siphon

International Nuclear Information System (INIS)

Tang Jun; Shang Jianqiang; Chen Jie; Li Fengxin; Liu Yanjun

2007-01-01

Objective: To determine the methods and results of treating traumatic pseudoaneurysms in siphon segment of internal carotid artery (ICA)by interventional therapy. Methods: Twelve cases of traumatic pseudoaneurysms in siphon segment of internal carotid artery were treated. The collateral circulation of Willis circle was observed after DSA. Different methods of treatment were applied according to the collateral circulation of Willis circle. Ten cases were treated by occlusion of ICA completely, 1 case was embolized by guglielmi detachable coil (GDC) only. Results: Nine of 12 treated by occlusion of ICA were cured. In the 3 cases who had poor collateral of Willis circle, one was cured by GDC embolization alone; one died 48 hours later after ICA occlusion though his consciousness and the activity of extremities were normal during the temporary balloon test occlusion (BTO) of ICA. One died during the training to improve the collateral of the Willis circle. Conclusion: ICA embolization is feasible for treatment of traumatic pseudoaneurysms in siphon segment of internal carotid artery after evaluating the collateral circulation of Willis circle. (authors)

Liver Trauma in the Kitchen: Preparing Whipped Cream with a Siphon Is Not without Risk

Directory of Open Access Journals (Sweden)

Jeremy Bourenne

2015-01-01

Full Text Available We report the case of a 36-year-old woman suffering from liver injury caused by the malfunction of a whipped cream siphon. When this patient handled the whipped cream siphon, the screwed metallic upper part of the siphon was suddenly dissociated from its base and came violently striking her right hypochondrium. At first, the severity of injury was underestimated. Subsequently, due to the persistence of pain experienced by the patient, an abdominal CT scan was performed. It highlighted a severe liver injury with rupture of a branch of the hepatic artery. The evolution was favorable after completion of an embolization and a secondary capsular rupture.

Analysis of 3D geometry in the stenosis of internal carotid artery siphon

International Nuclear Information System (INIS)

Xie Sheng; Xiao Jiangxi; Huang Yining; Zhang Chi; Li Deyu; Li Shuyu

2010-01-01

Objective: To identify the differences of 3D geometry of internal carotid artery (ICA) siphon between the controls and patients with ICA siphon stenosis. Methods: The clinical and imaging data of the inpatients under, vent carotid artery MRA in the past three years were collected. All patients were divided into the control group (17 males and 14 females with mean age of 67.5 years) and ICA siphon stenosis group (20 males and 9 females with mean age of 58.6 years). There were 5 smokers and 9 smokers in two groups, respectively. The atheroselerotic predisposing factors were compared between the two groups using chi-square test and paired t-test. In order to extract the 3D geometry of ICA siphon, the MRA data were transferred to PC and processed with the software of Mimics. The average curvature radius (ACR) was calculated and paired t-test was applied to determine the bilateral differences in the controls. According to the stenotic site of ICA siphon, ICA siphon stenosis group was divided into C2 segment stenosis group and C4 segment stenosis group. The differences of ACR among the control group, C2 segment stenosis group and C4 segment stenosis group were compared. In addition, the values of ACR in the stenotic and normal sides were compared with paired t-test in patients with unilateral C2 segment stenosis. Results: No significant differences were found in gender and smoker between the control group and the ICA siphon stenosis group (χ 2 =1.63, P>0.05; χ 2 =1.86, P>0.05). The systolic blood pressure was (146.6±21.3) mm Hg (1 mm Hg=0.133 kPa)and (140.3±17.3) mm Hg respectively in the ICA siphon stenosis group and the control group. The serum glucose level was (5.94±1.89) mmoL/L and (6.79±3.57) mmol/L respectively in two groups. The serum cholesterol level and triglyceride level were (4.57±0.87) mmol/L, (1.34±0.63) mmoL/L and (4.75±1.70) mmol/L, (1.54±0.72) mmol/L respectively in two groups. There were no differences in the atherosclerotic predisposing

Numerical Simulation of a Single-Phase Closed-Loop Thermo-Siphon in LORELEI Test Device

International Nuclear Information System (INIS)

Gitelman, D.; Shenha, H.; Gonnier, Ch.; Tarabelli, D.; Sasson, A.; Weiss, Y.; Katz, M.

2014-01-01

The LORELEI experimental setup in the Jules Horowitz Reactor (JHR) is dedicated for the study of fuel during a Loss of Coolant Accident (LOCA). The main objective of the LORELEI(2) (Light-Water One-Rod Equipment for LOCA Experimental Investigation) is to study the thermal-mechanical behavior of fuel during such an accident and to produce a short half-life fission products source term. In order to study those phenomena, the fuel sample will experience a transient neutron flux field, which in turn will generate a Linear Heat Generation Rate (LHGR) and determine the temperature of the fuel and its cladding, simulating the behavior of the fuel and the cladding during a LOCA accident. In order to reproduce a LOCA-type transient sequence, the experimental test device will be located on a displacement device. The displacement device moves the test device in the flux field in order to generate a representing LHGR in the fuel or temperature of its cladding. The LOCA-type transient sequence has four major features: „h An adiabatic heating of the fuel up to the ballooning and burst occurrence. „h High temperature plateau which will promote clad oxidation. „h Passive precooling by thermal inertia. „h Water re-flooding and quenching. The challenge in the thermo-hydraulic design of the LORELEI test section is in defining a one closed water capsule design that can operate as a thermo-siphon at re-irradiation phase and also can reproduce all LOCA-type transient sequence phases. This design should be validated and verified to fill all safety and regulation requirements. This work aims to investigate fluid flow behavior of a single-phase thermo-siphon in the LORELEI test device, as part of the conceptual design and optimization study. The complexity of the flow field in the LORELEI test device, as a closed-loop thermo-siphon, is due to the opposing forces in the device - buoyancy forces and natural convection flow generated (mainly) by the fuel power in the hot channel

SHRIMP (CRANGON-CRANGON L) BROWSING UPON SIPHON TIPS INHIBITS FEEDING AND GROWTH IN THE BIVALVE MACOMA-BALTHICA (L)

NARCIS (Netherlands)

KAMERMANS, P; HUITEMA, HJ

1994-01-01

The influence of siphon browsing on the feeding behaviour and growth of Macoma balthica, a deposit-feeding bivalve, was studied in three manipulative experiments. Browsing was simulated by removing part of the inhalant siphon with scissors, or studied by exposing the bivalves to shrimps (Crangon

Feasibility study of the thermo-siphon mock-up test

International Nuclear Information System (INIS)

Choi, Jung Woon; Kim, Young Jin; Lee, Kye Hong; Kim, Young Ki; Jeong, Sang Kwon

2004-09-01

Described is the feasibility of the thermo-siphon mock-up test for the HANARO-CNS facility. The purposes of the mock-up tests are discussed in detail as the three concepts: for the detailed design, for the operation of the CNS facility, for the safety assurance of itself. This report considers the two stages of mock-up tests in terms of the experimental schedule and plan. As the first stage, the small-size mock-up test using Argon will be implemented to obtain the experience in the cryogenic fluid and to understand the basic concept of the CNS thermo-siphon. In the second stage, two kinds of mock-up tests are discussed: the full-scale mock-up test using liquid hydrogen or the integrated final test using hydrogen outside the reactor after the full-scale mock-up test using Freon gas. The contents discussed in this report will be the basis or the guide lines for the mock-up test. In addition, the results of the mock-up test will be the foundation for the safe operation of the HANARO-CNS facility

Density-Gradient Mediated Band Extraction of Leukocytes from Whole Blood Using Centrifugo-Pneumatic Siphon Valving on Centrifugal Microfluidic Discs

Science.gov (United States)

Kearney, Sinéad M.; Kilcawley, Niamh A.; Early, Philip L.; Glynn, Macdara T.; Ducrée, Jens

2016-01-01

Here we present retrieval of Peripheral Blood Mononuclear Cells by density-gradient medium based centrifugation for subsequent analysis of the leukocytes on an integrated microfluidic “Lab-on-a-Disc” cartridge. Isolation of white blood cells constitutes a critical sample preparation step for many bioassays. Centrifugo-pneumatic siphon valves are particularly suited for blood processing as they function without need of surface treatment and are ‘low-pass’, i.e., holding at high centrifugation speeds and opening upon reduction of the spin rate. Both ‘hydrostatically’ and ‘hydrodynamically’ triggered centrifugo-pneumatic siphon valving schemes are presented. Firstly, the geometry of the pneumatic chamber of hydrostatically primed centrifugo-pneumatic siphon valves is optimised to enable smooth and uniform layering of blood on top of the density-gradient medium; this feature proves to be key for efficient Peripheral Blood Mononuclear Cell extraction. A theoretical analysis of hydrostatically primed valves is also presented which determines the optimum priming pressure for the individual valves. Next, ‘dual siphon’ configurations for both hydrostatically and hydrodynamically primed centrifugo-pneumatic siphon valves are introduced; here plasma and Peripheral Blood Mononuclear Cells are extracted through a distinct siphon valve. This work represents a first step towards enabling on disc multi-parameter analysis. Finally, the efficiency of Peripheral Blood Mononuclear Cells extraction in these structures is characterised using a simplified design. A microfluidic mechanism, which we termed phase switching, is identified which affects the efficiency of Peripheral Blood Mononuclear Cell extraction. PMID:27167376

The Heat Exchanger for Passive Part ECCS of WWER-1000 on Base of the Thermo siphons

International Nuclear Information System (INIS)

Kirov, V.; Chulkin, O.

2008-01-01

One of NPP's systems providing safe operation is the system of emergency core cooling system (ECCS), which primary function in accidents is to flood the nuclear reactor core and to assure the sub critical condition and core cooling. At injection of cold water in reactor thermal stresses and thermal fatigue in the vessel cladding and constructional materials are arise. Low temperature of the water injected in reactor is a reason of occurrence of these undesirable consequences. Some variants of the water heating in accumulators of ECCS are considered. Now at Ukrainian NPPs the electrical heating in accumulators is used. Electrical heaters create the essential additional loading to diesel generators at imposing of two accidents - the large break and losses of power supplies on own needs. It is offered to use a heater in accumulators that working by a principle two-phase thermal siphon which advantages is: small dimensions, small delay and design reliability. In such heat exchanger the heating medium is a direct steam and the heated up medium is water with boric acid from accumulators of ECCS. Under requirements of the service regulations of ECCS accumulators it is necessary to guarantee injected water heating up to 90 ?? in case of a small break and to 150 ?? in case of the large break. Results of calculations for different external diameters of a tube of thermal siphon which have allowed to define the constructive sizes of heat exchanger, providing necessary conditions for required functioning of passive part ECCS are submitted The calculation and analysis of operating modes of the changed circuit of passive part ECCS for various accidents is carried out. The calculated pressure drop indicates that changes do not have essential influence on system work as a whole. Thus, the submitted decision provides the increase of reliability of ECCS at small and large breaks accidents, i.e. in all modes stipulated by the project.(author)

Commissioning of the Liquid Nitrogen Thermo-Siphon System for NASA-JSC Chamber-A

Science.gov (United States)

Homan, J.; Montz, M.; Ganni, V.; Sidi-Yekhlef, A.; Knudsen, P.; Garcia, S.; Garza, J.

2013-01-01

NASA's Space Environment Simulation Laboratory's (SESL) Chamber A, located at the Johnson Space Center in Houston Texas has recently implemented major enhancements of its cryogenic and vacuum systems. The new liquid nitrogen (LN2) thermo-siphon system was successfully commissioned in August of 2012. Chamber A, which has 20 K helium cryo-panels (or shrouds ) which are shielded by 80 K nitrogen shrouds, is capable of simulating a deep space environment necessary to perform ground testing of NASA s James Webb Space Telescope (JWST). Chamber A s previous system used forced flow LN2 cooling with centrifugal pumps, requiring 200,000 liters of LN2 to cool-down and consuming 180,000 liters per day of LN2 in steady operation. The LN2 system did not have the reliability required to meet the long duration test of the JWST, and the cost estimate provided in the initial approach to NASA-JSC by the sub-contractor for refurbishment of the system to meet the reliability goals was prohibitive. At NASA-JSC's request, the JLab Cryogenics Group provided alternative options in 2007, including a thermo-siphon, or natural flow system. This system, eliminated the need for pumps and used one tenth of the original control valves, relief valves, and burst disks. After the thermo-siphon approach was selected, JLab provided technical assistance in the process design, mechanical design, component specification development and commissioning oversight, while the installation and commissioning operations of the system was overseen by the Jacobs Technology/ESC group at JSC. The preliminary commissioning data indicate lower shroud temperatures, 70,000 liters to cool-down and less than 90,000 liters per day consumed in steady operation. All of the performance capabilities have exceeded the design goals. This paper will outline the comparison between the original system and the predicted results of the selected design option, and the commissioning results of thermo-siphon system.

Commissioning of the Liquid Nitrogen Thermo-Siphon System for NASA-JSC Chamber A

Science.gov (United States)

Homan, J.; Montz, M.; Ganni, V.; Sidi-Yekhlef, A.; Knudsen, P.; Garcia, S.; Garza, J.

2013-01-01

NASA s Space Environment Simulation Laboratory s (SESL) Chamber A, located at the Johnson Space Center in Houston Texas has recently implemented major enhancements of its cryogenic and vacuum systems. The new liquid nitrogen (LN) thermo-siphon system was successfully commissioned in August of 2012. Chamber A, which has 20 K helium cryo-panels (or shrouds ) which are shielded by 80 K nitrogen shrouds, is capable of simulating a deep space environment necessary to perform ground testing of NASA s James Webb Space Telescope (JWST). Chamber A s previous system used forced flow LN cooling with centrifugal pumps, requiring 220,000 liters of LN to cool-down and consuming 180,000 liters per day of LN in steady operation. The LN system did not have the reliability required to meet the long duration test of the JWST, and the cost estimate provided in the initial approach to NASA-JSC by the subcontractor for refurbishment of the system to meet the reliability goals was prohibitive. At NASA-JSC s request, the JLab Cryogenics Group provided alternative options in 2007, including a thermo-siphon, or natural flow system. This system, eliminated the need for pumps and used one tenth of the original control valves, relief valves, and burst disks. After the thermo-siphon approach was selected, JLab provided technical assistance in the process design, mechanical design, component specification development and commissioning oversight, while the installation and commissioning operations of the system was overseen by the Jacobs Technology/ESC group at JSC. The preliminary commissioning data indicate lower shroud temperatures, 68,000 liters to cool-down and less than 91,000 liters per day consumed in steady operation. All of the performance capabilities have exceeded the design goals. This paper will outline the comparison between the original system and the predicted results of the selected design option, and the commissioning results of thermo-siphon system.

Changes to the geometry and fluid mechanics of the carotid siphon in the pediatric Moyamoya disease.

Science.gov (United States)

Jamil, Muhammad; Tan, Germaine Xin Yi; Huq, Mehnaz; Kang, Heidi; Lee, Zhi Rui; Tang, Phua Hwee; Hu, Xi Hong; Yap, Choon Hwai

2016-12-01

The Moyamoya disease is a cerebrovascular disease that causes occlusion of the distal end of the internal carotid artery, leading to the formation of multiple tiny collateral arteries. To date, the pathogenesis of Moyamoya is unknown. Improved understanding of the changes to vascular geometry and fluid mechanics of the carotid siphon during disease may improve understanding of the pathogenesis, prognosis techniques and disease management. A retrospective analysis of Magnetic Resonance Angiography (MRA) images was performed for Moyamoya pediatric patients (MMD) (n = 23) and control (Ctrl) pediatric patients (n = 20). The Ctrl group was composed of patients who complained of headache and had normal MRA. We performed segmentation of MRA images to quantify geometric parameters of the artery. Computational fluid dynamics (CFD) was performed to quantify the hemodynamic parameters. MMD internal carotid and carotid siphons were smaller in cross-sectional areas, and shorter in curved vascular length. Vascular curvature remained constant over age and vascular size and did not change between Ctrl and MMD, but MMD carotid siphon had lower tortuosity in the posterior bend, and higher torsion in the anterior bend. Wall shear stress and secondary flows were significantly lower in MMD, but the ratio of secondary flow kinetic energy to primary flow kinetic energy were similar between MMD and Ctrl. There were alterations to both the geometry and the flow mechanics of the carotid siphons of Moyamoya patients but it is unclear whether hemodynamics is the cause or the effect of morphological changes observed.

Monosynaptic connections made by the sensory neurons of the gill- and siphon-withdrawal reflex in Aplysia participate in the storage of long-term memory for sensitization

OpenAIRE

Frost, William N.; Castellucci, Vincent F.; Hawkins, Robert D.; Kandel, Eric R.

1985-01-01

We have found that in the gill- and siphon- withdrawal reflex of Aplysia, the memory for short-term sensitization grades smoothly into long-term memory with increased amounts of sensitization training. One cellular locus for the storage of the memory underlying short-term sensitization is the set of monosynaptic connections between the siphon sensory cells and the gill and siphon motor neurons. We have now also found that these same monosynaptic connections participate in the storage of the m...

Spectropolarimetric Evidence for a Siphon Flow along an Emerging Magnetic Flux Tube

Energy Technology Data Exchange (ETDEWEB)

Requerey, Iker S.; Cobo, B. Ruiz [Instituto de Astrofísica de Canarias, Vía Láctea s/n, E-38205 La Laguna, Tenerife (Spain); Iniesta, J. C. Del Toro; Suárez, D. Orozco [Instituto de Astrofísica de Andalucía (CSIC), Apdo. de Correos 3004, E-18080 Granada (Spain); Rodríguez, J. Blanco [Grupo de Astronomía y Ciencias del Espacio, Universidad de Valencia, E-46980 Paterna, Valencia (Spain); Solanki, S. K.; Barthol, P.; Gandorfer, A.; Gizon, L.; Hirzberger, J.; Riethmüller, T. L.; Noort, M. van [Max-Planck-Institut für Sonnensystemforschung, Justus-von-Liebig-Weg 3, D-37077 Göttingen (Germany); Schmidt, W. [Kiepenheuer-Institut für Sonnenphysik, Schöneckstr. 6, D-79104 Freiburg (Germany); Pillet, V. Martínez [National Solar Observatory, 3665 Discovery Drive, Boulder, CO 80303 (United States); Knölker, M., E-mail: iker@iac.es [High Altitude Observatory, National Center for Atmospheric Research, P.O. Box 3000, Boulder, CO 80307-3000 (United States)

2017-03-01

We study the dynamics and topology of an emerging magnetic flux concentration using high spatial resolution spectropolarimetric data acquired with the Imaging Magnetograph eXperiment on board the sunrise balloon-borne solar observatory. We obtain the full vector magnetic field and the line of sight (LOS) velocity through inversions of the Fe i line at 525.02 nm with the SPINOR code. The derived vector magnetic field is used to trace magnetic field lines. Two magnetic flux concentrations with different polarities and LOS velocities are found to be connected by a group of arch-shaped magnetic field lines. The positive polarity footpoint is weaker (1100 G) and displays an upflow, while the negative polarity footpoint is stronger (2200 G) and shows a downflow. This configuration is naturally interpreted as a siphon flow along an arched magnetic flux tube.

Aquaponic Growbed Water Level Control Using Fog Architecture

Science.gov (United States)

Asmi Romli, Muhamad; Daud, Shuhaizar; Raof, Rafikha Aliana A.; Awang Ahmad, Zahari; Mahrom, Norfadilla

2018-05-01

Integrated Multi-Trophic Aquaculture (IMTA) is an advance method of aquaculture which combines species with different nutritional needs to live together. The combination between aquatic live and crops is called aquaponics. Aquatic waste that normally removed by biofilters in normal aquaculture practice will be absorbed by crops in this practice. Aquaponics have few common components and growbed provide the best filtration function. In growbed a siphon act as mechanical structure to control water fill and flush process. Water to the growbed comes from fish tank with multiple flow speeds based on the pump specification and height. Too low speed and too fast flow rate can result in siphon malfunctionality. Pumps with variable speed do exist but it is costly. Majority of the aquaponic practitioner use single speed pump and try to match the pump speed with siphon operational requirement. In order to remove the matching requirement some control need to be introduced. Preliminarily this research will show the concept of fill-and-flush for multiple pumping speeds. The final aim of this paper is to show how water level management can be done to remove the speed dependency. The siphon tried to be controlled remotely since wireless data transmission quite practical in vast operational area. Fog architecture will be used in order to transmit sensor data and control command. This paper able to show the water able to be retented in the growbed within suggested duration by stopping the flow in once predefined level.

Application of Self Cleaning Rapid Sand Filter in Water Treatment

Directory of Open Access Journals (Sweden)

Ali Reza Rahmani

2005-08-01

Full Text Available Rapid sand filter is one of the most important units in the water treatment plants. It has some difficulties in operation such as backwashing. For the solving of this problem a rapid sand filter has designed and built with the self-cleaning backwashing system. This system consist of 3 main constituents; one galvanized siphon and two galvanized steel tanks. One of them is used for filtration and the other used for the storage of filtrated water in elevation for backwashing the system. Water enter from upside of the filter through the inlet pipe, and collected from the under drainage pipe. Then filter water conduct to the storage tank and exit from outlet pipe. In the beginning, the head loss was low, but because of bed clogging by suspended solids, it increases gradually to the designed head loss (1.2m. Then the system is outed of the service automatically and the backwash is began. The main data for the design of system selected from the hydraulic rules of siphons and rapid sand filter criteria. After essential calculations it was constructed and was started operation. For the hydraulic studies a known volume of storage tank was selected and the time needed for the fill (in filtration stage and empty (in backwash stage of water volume with volumetric method were measured. In hydraulic studies the filter surface rate (SOR was selected about 5-7.5m3/m2/hr (1.39-2.08 lit/sec and the flow of water in siphon, during the backwashing was measured 8.7 lit/sec. It can be seen that the siphon passes 4-6 times the inlet raw water thus a negative pressure will created in the siphon which causes the water above the sand bed to be discharged automatically and rinse water from elevated tank flow under the sand bed and back wash it. So according to this study self cleaning rapid sand filter is very useful for water filtration, especially in small population community. The construction of system is rapid, simple and economic.

THE LIQUID NITROGEN SYSTEM FOR CHAMBER A; A CHANGE FROM ORIGINAL FORCED FLOW DESIGN TO A NATURAL FLOW (THERMO SIPHON) SYSTEM

International Nuclear Information System (INIS)

Homan, J.; Montz, M.; Ganni, V.; Sidi-Yekhlef, A.; Knudsen, P.; Creel, J.; Arenius, D.; Garcia, S.

2010-01-01

NASA at the Johnson Space Center (JSC) in Houston is presently working toward modifying the original forced flow liquid nitrogen cooling system for the thermal shield in the space simulation chamber-A in Building 32 to work as a natural flow (thermo siphon) system. Chamber A is 19.8 m (65 ft) in diameter and 35.66 m (117 ft) high. The LN 2 shroud environment within the chamber is approximately 17.4 m (57 ft) in diameter and 28 m (92 ft) high. The new thermo siphon system will improve the reliability, stability of the system. Also it will reduce the operating temperature and the liquid nitrogen use to operate the system. This paper will present the requirements for the various operating modes. System level thermodynamic comparisons of the existing system to the various options studied and the final option selected will be outlined. A thermal and hydraulic analysis to validate the selected option for the conversion of the current forced flow to natural flow design will be discussed. The proposed modifications to existing system to convert to natural circulation (thermo siphon) system and the design features to help improve the operations, and maintenance of the system will be presented.

Theoretical analysis and experimental investigation on performance of the thermal shield of accelerator cryomodules by thermo-siphon cooling of liquid nitrogen

Science.gov (United States)

Datta, T. S.; Kar, S.; Kumar, M.; Choudhury, A.; Chacko, J.; Antony, J.; Babu, S.; Sahu, S. K.

2015-12-01

Five beam line cryomodules with total 27 superconducting Radio Frequency (RF) cavities are installed and commissioned at IUAC to enhance the energy of heavy ion from 15 UD Pelletron. To reduce the heat load at 4.2 K, liquid nitrogen (LN2) cooled intermediate thermal shield is used for all these cryomodules. For three linac cryomodules, concept of forced flow LN2 cooling is used and for superbuncher and rebuncher, thermo-siphon cooling is incorporated. It is noticed that the shield temperature of superbuncher varies from 90 K to 110 K with respect to liquid nitrogen level. The temperature difference can't be explained by using the basic concept of thermo-siphon with the heat load on up flow line. A simple thermo-siphon experimental set up is developed to simulate the thermal shield temperature profile. Mass flow rate of liquid nitrogen is measured with different heat load on up flow line for different liquid levels. It is noticed that small amount of heat load on down flow line have a significant effect on mass flow rate. The present paper will be investigating the data generated from the thermosiphon experimental set up and a theoretical analysis will be presented here to validate the measured temperature profile of the cryomodule shield.

Host specificity and coevolution of Flavobacteriaceae endosymbionts within the siphonous green seaweed Bryopsis

OpenAIRE

Hollants, J.; Leliaert, F.; Verbruggen, H.; De Clerck, O.; Willems, A.

2013-01-01

The siphonous green seaweed Bryopsis harbors complex intracellular bacterial communities. Previous studies demonstrated that certain species form close, obligate associations with Flavobacteriaceae. A predominant imprint of host evolutionary history on the presence of these bacteria suggests a highly specialized association. In this study we elaborate on previous results by expanding the taxon sampling and testing for host–symbiont coevolution Therefore, we optimized a PCR protocol to directl...

Raphides in the Uncalcified Siphonous Green Seaweed, Codium minus (Schmidt P. C. Silva

Directory of Open Access Journals (Sweden)

Jeffrey S. Prince

2012-01-01

Full Text Available The vacuole of utricles, the outermost cell layer of the siphonous green seaweed, Codium minus, had numerous single needles and needle bundles. The crystals composing each needle appeared arranged in a twisted configuration, both ends were pointed, and each needle was contained in a matrix or membrane; bundles of needles appeared enclosed by a matrix. Chemical and electron diffraction analysis indicated that the needles consisted of calcium oxalate. This is the first paper on terrestrial plant-like raphides in an alga.

Treatment of carotid-siphon aneurysms by using willis stent-graft: an angiographic and histopathologic study in dogs

International Nuclear Information System (INIS)

Zhu Yueqi; Li Minghua; Xie Jian; Tan Huaqiao; Cheng Yingsheng; Wang Jianbo

2010-01-01

Objective: To establish a carotid siphon aneurysm model in dogs in order to test the mechanical features of a newly-designed Willis covered stent-graft and to investigate the histological reaction of the stent-implanted vessel during a follow-up period of 12 months. Methods: Twenty-four saccular sidewall aneurysms were surgically created in twelve dogs (group A) and 12 carotid siphon aneurysms in another twelve dogs (group B). A Willis stent-graft was implanted in each aneurysm. Angiography was performed immediately after the procedure and 1, 3, 6 and 12 months after the implantation to investigate the aneurysm isolation, endoleak, stent angulation, and the patency or restenosis of the parent artery. Light and scanning electronic microscopy were used to identify aneurysmal sac thrombi, intima hyperplasia and endothelial progress of the stent-loaded arterial segment. Results: In group B, postoperative immediate angiography demonstrated that two aneurysms had mild endoleak and three stents became angulated. Follow-up exam 12 months after the procedure revealed that all previous endoleaks disappeared, one parent artery became occluded and three parent arteries developed mild stenosis (< 50%). In group A, occlusion of parent artery was seen in one and mild stenosis (< 50%) in 2 cases. Electronic microscopy revealed new intima formation in all stents, and all aneurysmal sacs were filled with thrombi. In group B, the endothelialization process was not completed until 12 months after the stent implantation, and a marked correlation existed between endothelial cell arrangement and the hemodynamic orientation. Conclusion: It is feasible to treat carotid-siphon aneurysm in dog with a Willis stent-graft. The complete endothelialization of the covered stent in tortuous vessel takes longer time than that in rather straight vessel. (authors)

The usefulness of esophagography as a screening test for laryngopharyngeal reflux

International Nuclear Information System (INIS)

Kim, Tae Hoon; Chung, Phil Sang

2006-01-01

There are many articles about the role of barium esophagography for the diagnosis of gastroesophageal reflux disease. However, there are only rare articles reporting on laryngopharyngeal reflux disease. The purpose of this study is to evaluate the usefulness of performing esophagography with the water-siphon test as an initial screening test for patients with suspected laryngopharyngeal reflux. From October 2002 to December 2004, barium esophagography with the water-siphon test was performed for 707 patients who had the typical symptoms and telescopic findings of laryngopharyngeal reflux. The results of the 707 esophagograms (the group with laryngopharyngeal reflux) were compared with those of 122 patients who were confirmed as having gastroesophageal reflux upon performing pH-metry (the group with gastroesophageal reflux) and the 324 patients without laryngopharyngeal reflux symptoms (the control group). The results of the water-siphon test were classified into normal, mild, moderate and severe degrees of gastroesophageal reflux. On the water-siphon test for the laryngopharyneal reflux group patients, 71 patients had normal (10.0%), 207 had mild (29.2%), 201 had moderate (28.4%) and 228 had severe (32.2%) degrees of reflux. The positive rates of the water-siphon test were 90.0%, 89.3% and 54.6% for the groups with laryngopharyngeal reflux, gastroesophageal reflux and the control group, respectively. A statistically significant difference was observed between the group with laryngopharyngeal reflux and the control group, and between the group with gastroesophageal reflux and the control group, respectively (ρ < 0.05). Esophagography with the water-siphon test is useful as an initial screening test for laryngopharyngeal reflux disease

The usefulness of esophagography as a screening test for laryngopharyngeal reflux

Energy Technology Data Exchange (ETDEWEB)

Kim, Tae Hoon; Chung, Phil Sang [Dankook University Hospital, Cheonan (Korea, Republic of)

2006-04-15

There are many articles about the role of barium esophagography for the diagnosis of gastroesophageal reflux disease. However, there are only rare articles reporting on laryngopharyngeal reflux disease. The purpose of this study is to evaluate the usefulness of performing esophagography with the water-siphon test as an initial screening test for patients with suspected laryngopharyngeal reflux. From October 2002 to December 2004, barium esophagography with the water-siphon test was performed for 707 patients who had the typical symptoms and telescopic findings of laryngopharyngeal reflux. The results of the 707 esophagograms (the group with laryngopharyngeal reflux) were compared with those of 122 patients who were confirmed as having gastroesophageal reflux upon performing pH-metry (the group with gastroesophageal reflux) and the 324 patients without laryngopharyngeal reflux symptoms (the control group). The results of the water-siphon test were classified into normal, mild, moderate and severe degrees of gastroesophageal reflux. On the water-siphon test for the laryngopharyneal reflux group patients, 71 patients had normal (10.0%), 207 had mild (29.2%), 201 had moderate (28.4%) and 228 had severe (32.2%) degrees of reflux. The positive rates of the water-siphon test were 90.0%, 89.3% and 54.6% for the groups with laryngopharyngeal reflux, gastroesophageal reflux and the control group, respectively. A statistically significant difference was observed between the group with laryngopharyngeal reflux and the control group, and between the group with gastroesophageal reflux and the control group, respectively ({rho} < 0.05). Esophagography with the water-siphon test is useful as an initial screening test for laryngopharyngeal reflux disease.

A One-Dimensional Hydrodynamic and Water Quality Model for a Water Transfer Project with Multihydraulic Structures

OpenAIRE

Yujun Yi; Caihong Tang; Zhifeng Yang; Shanghong Zhang; Cheng Zhang

2017-01-01

The long Middle Route of the South to North Water Transfer Project is composed of complex hydraulic structures (aqueduct, tunnel, control gate, diversion, culvert, and diverted siphon), which generate complex flow patterns. It is vital to simulate the flow patterns through hydraulic structures, but it is a challenging work to protect water quality and maintain continuous water transfer. A one-dimensional hydrodynamic and water quality model was built to understand the flow and pollutant movem...

Design of aquaponics water monitoring system using Arduino microcontroller

Science.gov (United States)

Murad, S. A. Z.; Harun, A.; Mohyar, S. N.; Sapawi, R.; Ten, S. Y.

2017-09-01

This paper describes the design of aquaponics water monitoring system using Arduino microcontroller. Arduino Development Environment (IDE) software is used to develop a program for the microcontroller to communicate with multiple sensors and other hardware. The circuit of pH sensor, temperature sensor, water sensor, servo, liquid crystal displays (LCD), peristaltic pump, solar and Global System for Mobile communication (GSM) are constructed and connected to the system. The system powered by a rechargeable battery using solar energy. When the results of pH, temperature and water sensor are out of range, a notification message will be sent to a mobile phone through GSM. If the pH of water is out of range, peristaltic pump is automatic on to maintain back the pH value of water. The water sensor is fixed in the siphon outlet water flow to detect water flow from grow bed to the fish tank. In addition, servo is used to auto feeding the fish for every 12 hours. Meanwhile, the LCD is indicated the pH, temperature, siphon outlet water flow and remaining time for the next feeding cycle. The pH and temperature of water are set in the ranges of 6 to 7 and 25 °C to 30 °C, respectively.

TNX GeoSiphon Cell (TGSC-1) Phase II Minimum Flushing Velocity Deployment/Demonstration Final Report

Energy Technology Data Exchange (ETDEWEB)

Phifer, M.A.

1999-10-25

The TNX Area is a semi-works facility for the Savannah River Technology Center (SRTC), which is located one-quarter mile from the Savannah river at the Savannah River Site. As the result of TNX operation, groundwater contamination has occurred. The predominant contaminants detected in the flood plain downgradient from TNX are trichloroethylene (TCE) and nitrate.Treatability studies into the applicability of a groundwater remediation system combining GeoSiphon Cell and zero-valent iron technologies for treatment of the TCE-contaminated groundwater at TNX have been conducted. These treatability studies have been conducted by SRTC under the sponsorship of the Environmental Restoration Department.

TNX GeoSiphon Cell (TGSC-1) Phase II Minimum Flushing Velocity Deployment/Demonstration Final Report

International Nuclear Information System (INIS)

Phifer, M.A.

1999-01-01

The TNX Area is a semi-works facility for the Savannah River Technology Center (SRTC), which is located one-quarter mile from the Savannah river at the Savannah River Site. As the result of TNX operation, groundwater contamination has occurred. The predominant contaminants detected in the flood plain downgradient from TNX are trichloroethylene (TCE) and nitrate.Treatability studies into the applicability of a groundwater remediation system combining GeoSiphon Cell and zero-valent iron technologies for treatment of the TCE-contaminated groundwater at TNX have been conducted. These treatability studies have been conducted by SRTC under the sponsorship of the Environmental Restoration Department

The wound response in the siphonous alga Caulerpa simpliciuscula C.Ag.:

International Nuclear Information System (INIS)

Hawthorne, D.B.; Dreher, T.W.; Grant, B.R.

1981-01-01

Following on from a previous study on changes in cytology and fine structure during the wound response in the siphonous green alga Caulerpa simpliciuscula (Dreher, Grant and Wetherbee 1978), changes in the carbon metabolism during in this wound response have been studied. There was a decrease in the rate of photosynthesis and an increase in the rate of respiration immediately on wounding, but rates of both photosynthesis and respiration returned to those of unwounded tissues within 6 hours. Wounding depressed the rate of starch synthesis and sucrose synthesis but increased the rate of synthesis of soluble 1,3 β-glucan, lipid and sulphated polysaccharide. When the flow of carbon from these various compounds was studied by means of pulse chase experiments, it was found that only sucrose and sulphated polysaccharide showed different kinetics in control and wounded tissue. The changes which were observed are consistent with direct involvement of sulphated polysaccharides in the formation of structures formed during the wound healing process. (author)

Well Installation and Sampling Report for Monitoring Wells TCM6 TCM7, and TNX 28D - 40D and GeoSiphon Cell TGSC-2

International Nuclear Information System (INIS)

Nichols, R.L.

1999-01-01

The shallow groundwater and sediments beneath the TNX Area are contaminated with both dissolved and residual chlorinated volatile organic compounds (CVOCs) such as trichloroethylene (TCE), carbon tetrachloride and perchloroethylene (PCE). The Savannah River Technology Center (SRTC) is studying a new technology for remediating CVOCs known as GeoSiphon

Analysis of flow and LDL concentration polarization in siphon of internal carotid artery: Non-Newtonian effects.

Science.gov (United States)

Sharifi, Alireza; Niazmand, Hamid

2015-10-01

Carotid siphon is known as one of the risky sites among the human intracranial arteries, which is prone to formation of atherosclerotic lesions. Indeed, scientists believe that accumulation of low density lipoprotein (LDL) inside the lumen is the major cause of atherosclerosis. To this aim, three types of internal carotid artery (ICA) siphon have been constructed to examine variations of hemodynamic parameters in different regions of the arteries. Providing real physiological conditions, blood considered as non-Newtonian fluid and real velocity and pressure waveforms have been employed as flow boundary conditions. Moreover, to have a better estimation of risky sites, the accumulation of LDL particles has been considered, which has been usually ignored in previous relevant studies. Governing equations have been discretized and solved via open source OpenFOAM software. A new solver has been built to meet essential parameters related to the flow and mass transfer phenomena. In contrast to the common belief regarding negligible effect of blood non-Newtonian behavior inside large arteries, current study suggests that the non-Newtonian blood behavior is notable, especially on the velocity field of the U-type model. In addition, it is concluded that neglecting non-Newtonian effects underestimates the LDL accumulation up to 3% in the U-type model at the inner side of both its bends. However, in the V and C type models, non-Newtonian effects become relatively small. Results also emphasize that the outer part of the second bend at the downstream is also at risk similar to the inner part of the carotid bends. Furthermore, from findings it can be implied that the risky sites strongly depend on the ICA shape since the extension of the risky sites are relatively larger for the V-type model, while the LDL concentrations are higher for the C-type model. Copyright © 2015 Elsevier Ltd. All rights reserved.

Conceptual design and feasibility test of two-phase hydrogen thermal siphon system of CNS in CARR

International Nuclear Information System (INIS)

Bi Qincheng; Chen Tingkuan; Feng Quanke; Du Shejiao; Li Xiaoming; Wei Liang

2004-01-01

Conceptual design of the hydrogen system of cold neutron source (CNS) in China Advanced Research Reactor (CARR) was proposed, and feasibility test was carried out. In order to determine the void fraction in neutron moderator, the circulation ability of the two-phase hydrogen thermal siphon system, and the structure of components of the CNS, the mockup test was performed using Freon-113 as working fluid. To obtain the modeling criterion so that the above experimental results can be applied to the design of CARR, the bubble rising velocities in different liquids were investigated to study the effects of physical properties such as density, viscosity and surface tension on bubble rising velocity, void fraction and circulation ability

Testing of GFL Geosiphon; FINAL

International Nuclear Information System (INIS)

Steimke, J.L.

2001-01-01

A full-scale, transparent replica of a GeoSiphon was constructed in the TFL to test a new concept, using a solar powered vacuum pump to remove accumulated gases from the air chamber. It did not have a treatment cell containing iron filings as do the actual TNX GeoSiphons in the field, but it was accurate in all other respects. The gas generation that is observed in an actual GeoSiphon was simulated by air injection at the inlet of the TFL GeoSiphon. After facility shakedown, three stages of testing were conducted: verification testing, parametric testing and long term testing. In verification testing, the TFL GeoSiphon was used to reproduce a particular test at TNX in which the water flowrate decreased gradually as the result of air accumulation at the crest of a siphon without an air chamber. For this test the vacuum pump was not used and the air chamber was initially filled with air rather than water. Agreement between data from the TNX GeoSiphon and the TFL GeoSiphon was good, which gave confidence that the TFL GeoSiphon was a good hydraulic representation of the TNX GeoSiphon. For the remaining tests, the solar powered vacuum pump and air chamber were used. In parametric testing, steady state runs were made for water flowrates ranging from 1 gpm to 19 gpm, air injection rates ranging from 0 to 77 standard cc/min and outfall line angles ranging from vertical to 60 degrees from vertical. In all cases, the air chamber and vacuum pump removed nearly all of the air and the GeoSiphon operated without problems. In long term testing, the GeoSiphon was allowed to run continuously for 21 days at one set of conditions. During this time the solar cell kept the storage battery fully charged at all times and the control circuit for the vacuum pump operated reliably. The solar panel was observed to have a large excess capacity when used with the vacuum pump. With two changes, the concept of using a solar powered vacuum pump attached to an air chamber should be ready for long

Water column separation in power plant circulating water systems

International Nuclear Information System (INIS)

Papadakis, C.N.

1977-01-01

Power plant circulating water system condensers operate with a siphon. Column separation is a common occurence in such condensers during low pressure transients. The assumptions that no gas evolves from solution leads to very conservative values of maximum pressures upon rejoining of separated column. A less conservative method led to the development of a macroscopic mathematical model including the presence of air and vapor in a cavity which forms at the top of the condenser. The method of characteristics is used to solve the equations. A case study is analyzed to illustrate the applicability of the developed mathematical model and to provide comparisons of the results obtained

Theoretical study on loss of coolant accident of a research reactor

International Nuclear Information System (INIS)

Lee, Kwon-Yeong; Kim, Wan-Soo

2016-01-01

Highlights: • A theoretical model of siphon breaking phenomena was developed. • A general formula using Chisholm coefficient B was proposed. • The safety requirements regarding a loss of coolant accident of research reactors could be found out. - Abstract: Under the design conditions of a research reactor, the siphon phenomenon induced by pipe rupture can cause continuous efflux of water. In order to prevent water efflux, an additional facility is necessary. A siphon breaker is a type of safety facility that can resist the loss of coolant effectively. However, analysis of siphon breaking is complex since it comprises two-phase flow and there are many inputs to be considered. For this reason, we analyzed the experimental results to develop a theoretical model of siphon breaking phenomena. Developed model is based on fluid mechanics and Chisholm model. From Bernoulli’s equation, the velocity and quantity as well as undershooting height, water level, pressure, friction coefficient, and factors related to the two-phase flow could be calculated. The Chisholm model, which is able to analyze the two-phase flow, can predict the results in a manner similar to those obtained from a real-scale experiment, and a general formula using Chisholm coefficient B was proposed in this study. Also, we verified the theoretical model and concluded that it is possible to analyze the siphon breaking. Moreover, the design conditions that can satisfy the safety requirements regarding a loss of coolant accident of research reactors could be found out by using the theoretical model. In conclusion, we propose the theoretical model which can analyze the siphon breaking as real, and it is helpful not only to analyze but also to design the siphon breaker.

Pseudomonas aeruginosa outbreak in a pediatric oncology care unit caused by an errant water jet into contaminated siphons.

Science.gov (United States)

Schneider, Henriette; Geginat, Gernot; Hogardt, Michael; Kramer, Alexandra; Dürken, Matthias; Schroten, Horst; Tenenbaum, Tobias

2012-06-01

We analyzed an outbreak of invasive infections with an exotoxin U positive Pseudomonas aeruginosa strain within a pediatric oncology care unit. Environmental sampling and molecular characterization of the Pseudomonas aeruginosa strains led to identification of the outbreak source. An errant water jet into the sink within patient rooms was observed. Optimized outbreak management resulted in an abundance of further Pseudomonas aeruginosa infections within the pediatric oncology care unit.

Effect of Cervical Siphon of External and Internal Carotid Arteries.

Science.gov (United States)

Singh, Rajani; Tubbs, Richard Shane

2017-10-01

Variant courses, configuration, and branching pattern of the external and internal carotid arteries, especially when curved in S-shape, are important for hemodynamic changes and clinical implications. Therefore, the aim of the study is to report abnormal cervical siphons observed in external and internal carotid arteries to explore clinical significance by review of literature and hemodynamic changes theoretically.The right common carotid artery bifurcated into external and internal carotid arteries at the level of the upper border of thyroid cartilage in a 70-year-old female cadaver. After bifurcation, the external carotid artery underwent severe tortuosity coursing through 5 bends at points A, B, C, D, and E from its origin to termination and 2 bends at A' and B' in internal carotid artery in the cervical region. The angles between inflow and out flow of the blood at the bends were measured and the change in velocity at each bend was computed for both arteries. Hemodynamic changes were calculated, compared and relevant clinical complications were theoretically correlated.The angles of 20°, 30°, 51°, 52°, 60°, and 28°, 48° were formed by 5 bends of external and 2 bends of internal carotid arteries, respectively. The curved courses of these arteries caused reduction in velocity/stasis, turbulence, and low shear stress. Such kinks might cause stroke, ischemia and mistaken for tumors and abscess in imagery leading to or otherwise producing iatrogenic repercussions. This study will be useful for anatomists, clinicians, and radiologists.

The impact of fillers on lineup performance

OpenAIRE

Wetmore, Stacy A.; McAdoo, Ryan M.; Gronlund, Scott D.; Neuschatz, Jeffrey S.

2017-01-01

Filler siphoning theory posits that the presence of fillers (known innocents) in a lineup protects an innocent suspect from being chosen by siphoning choices away from that innocent suspect. This mechanism has been proposed as an explanation for why simultaneous lineups (viewing all lineup members at once) induces better performance than showups (one-person identification procedures). We implemented filler siphoning in a computational model (WITNESS, Clark, Applied Cognitive Psychology 17:629...

Water heating solar system using collector with polycarbonate absorber surface

Energy Technology Data Exchange (ETDEWEB)

Souza, Luiz Guilherme Meira de; Sodre, Dilton; Cavalcanti, Eduardo Jose Cidade; Souza, Luiz Guilherme Vieira Meira de; Mendes, Jose Ubiragi de Lima [Universidade Federal do Rio Grande do Norte (UFRN), Natal, RN (Brazil)], e-mails: lguilherme@dem.ufrn.br, diltonsodre@ifba.edu.br, ubiragi@ct.ufrn.br

2010-07-01

It is presented s solar collector to be used in a heating water for bath system, whose main characteristics are low cost and easy fabrication and assembly processes. The collector absorber surface consists of a polycarbonate plate with an area of 1.5 m{sup 2}. The water inlet and outlet are made of PVC 50mm, and were coupled to a 6mm thick polycarbonate plate using fiberglass resin. A 200 liters thermal reservoir will be used. This reservoir is also alternative. The absorber heating system works under thermo-siphon regimen. Thermal parameters will be evaluated to prove the feasibility of the studied solar heating system to obtain bath water for a four people family. (author)

Hydraulic logic gates: building a digital water computer

Science.gov (United States)

Taberlet, Nicolas; Marsal, Quentin; Ferrand, Jérémy; Plihon, Nicolas

2018-03-01

In this article, we propose an easy-to-build hydraulic machine which serves as a digital binary computer. We first explain how an elementary adder can be built from test tubes and pipes (a cup filled with water representing a 1, and empty cup a 0). Using a siphon and a slow drain, the proposed setup combines AND and XOR logical gates in a single device which can add two binary digits. We then show how these elementary units can be combined to construct a full 4-bit adder. The sequencing of the computation is discussed and a water clock can be incorporated so that the machine can run without any exterior intervention.

Host specificity and coevolution of Flavobacteriaceae endosymbionts within the siphonous green seaweed Bryopsis.

Science.gov (United States)

Hollants, Joke; Leliaert, Frederik; Verbruggen, Heroen; De Clerck, Olivier; Willems, Anne

2013-06-01

The siphonous green seaweed Bryopsis harbors complex intracellular bacterial communities. Previous studies demonstrated that certain species form close, obligate associations with Flavobacteriaceae. A predominant imprint of host evolutionary history on the presence of these bacteria suggests a highly specialized association. In this study we elaborate on previous results by expanding the taxon sampling and testing for host-symbiont coevolution Therefore, we optimized a PCR protocol to directly and specifically amplify Flavobacteriaceae endosymbiont 16S rRNA gene sequences, which allowed us to screen a large number of algal samples without the need for cultivation or surface sterilization. We analyzed 146 Bryopsis samples, and 92 additional samples belonging to the Bryopsidales and other orders within the class Ulvophyceae. Results indicate that the Flavobacteriaceae endosymbionts are restricted to Bryopsis, and only occur within specific, warm-temperate and tropical clades of the genus. Statistical analyses (AMOVA) demonstrate a significant non-random host-symbiont association. Comparison of bacterial 16S rRNA and Bryopsis rbcL phylogenies, however, reveal complex host-symbiont evolutionary associations, whereby closely related hosts predominantly harbor genetically similar endosymbionts. Bacterial genotypes are rarely confined to a single Bryopsis species and most Bryopsis species harbored several Flavobacteriaceae, obscuring a clear pattern of coevolution. Copyright © 2013 Elsevier Inc. All rights reserved.

Performance of a 10-kJ SMES model cooled by liquid hydrogen thermo-siphon flow for ASPCS study

International Nuclear Information System (INIS)

Makida, Y; Shintomi, T; Hamajima, T; Tsuda, M; Miyagi, D; Ota, N; Katsura, M; Ando, K; Takao, T; Tsujigami, H; Fujikawa, S; Hirose, J; Iwaki, K; Komagome, T

2015-01-01

We propose a new electrical power storage and stabilization system, called an Advanced Superconducting Power Conditioning System (ASPCS), which consists of superconducting magnetic energy storage (SMES) and hydrogen energy storage, converged on a liquid hydrogen station for fuel cell vehicles. A small 10- kJ SMES system, in which a BSCCO coil cooled by liquid hydrogen was installed, was developed to create an experimental model of an ASPCS. The SMES coil is conductively cooled by liquid hydrogen flow through a thermo-siphon line under a liquid hydrogen buffer tank. After fabrication of the system, cooldown tests were carried out using liquid hydrogen. The SMES coil was successfully charged up to a nominal current of 200 A. An eddy current loss, which was mainly induced in pure aluminum plates pasted onto each pancake coils for conduction cooling, was also measured. (paper)

Surface wastewater in Samara and their impact on water basins as water supply sources

Science.gov (United States)

Strelkov, Alexander; Shuvalov, Mikhail; Gridneva, Marina

2017-10-01

The paper gives an overview of surface wastewater outlets in Samara through the rainwater sewer system into the Saratov water reservoir and the Samara river. The rainwater sewer system in Samara is designed and executed according to a separate scheme, except for the old part of the city, where surface run-off is dumped into the sewer system through siphoned drain. The rainwater system disposes of surface, drainage, industrial clean-contamined waters, emergency and technology discharges from the city’s heat supply and water supply systems. The effluent discharge is carried out by means of separate wastewater outlets into ravines or directly into the Samara river and the Saratov water reservoir without cleaning. The effluent discharge is carried out through the rainwater sewer system with 17 wastewater outlets into the Saratov water reservoir. In the Samara river, surface runoff drainage and clean-contamined water of industrial enterprises is carried out through 14 wastewater outlets. This study emphasizes the demand to arrange effluent discharge and construction of sewage treatment plants to prevent contamination of water objects by surface run-off from residential areas and industrial territories.

Thermal-hydraulic analysis of loss-of-coolant accident in the JMTR

International Nuclear Information System (INIS)

Sakurai, Fumio; Oyamada, Rokuro

1985-02-01

The reevaluation of the Loss-of-Coolant Accident (LOCA) was required through the process of a safety review for the Japan Materials Testing Reactor (JMTR) core conversion from the high-enriched uranium fuel (Enrichment : 93%) to the medium-enriched uranium fuel (Enrichment : 45%). The following were concluded by thermal-hydraulic analysis of a LOCA caused by a double-ended pipe break in the JMTR primary cooling system. (1) The fuel in the core does not burn-out as long as it is covered with water. (2) A larger siphon break valve (larger than phi60mm) should be installed instead of the present one (phi25mm) on the primary cooling system in order to prevent the core from being uncovered with water in case of a LOCA caused by a double-ended pipe break. The present siphon break valve was installed to keep the core covered with water in case of a LOCA caused by a small pipe rupture. In this analysis, the Siphon Breaker Analysis Code (SBAC) was written in order to analyse the size of the siphon break valve and its accuracy was confirmed to be within 5% through a verification experiment. (author)

A One-Dimensional Hydrodynamic and Water Quality Model for a Water Transfer Project with Multihydraulic Structures

Directory of Open Access Journals (Sweden)

Yujun Yi

2017-01-01

Full Text Available The long Middle Route of the South to North Water Transfer Project is composed of complex hydraulic structures (aqueduct, tunnel, control gate, diversion, culvert, and diverted siphon, which generate complex flow patterns. It is vital to simulate the flow patterns through hydraulic structures, but it is a challenging work to protect water quality and maintain continuous water transfer. A one-dimensional hydrodynamic and water quality model was built to understand the flow and pollutant movement in this project. Preissmann four-point partial-node implicit scheme was used to solve the governing equations in this study. Water flow and pollutant movement were appropriately simulated and the results indicated that this water quality model was comparable to MIKE 11 and had a good performance and accuracy. Simulation accuracy and model uncertainty were analyzed. Based on the validated water quality model, six pollution scenarios (Q1 = 10 m3/s, Q2 = 30 m3/s, and Q3 = 60 m3/s for volatile phenol (VOP and contaminant mercury (Hg were simulated for the MRP. Emergent pollution accidents were forecasted and changes of water quality were analyzed according to the simulations results, which helped to guarantee continuously transferring water for a large water transfer project.

Capturing Flow-weighted Water and Suspended Particulates from Agricultural Canals During Drainage Events.

Science.gov (United States)

Bhadha, Jehangir H; Sexton, Anne; Lang, Timothy A; Daroub, Samira H

2017-11-07

The purpose of this study is to describe the methods used to capture flow-weighted water and suspended particulates from farm canals during drainage discharge events. Farm canals can be enriched by nutrients such as phosphorus (P) that are susceptible to transport. Phosphorus in the form of suspended particulates can significantly contribute to the overall P loads in drainage water. A settling tank experiment was conducted to capture suspended particulates during discrete drainage events. Farm canal discharge water was collected in a series of two 200 L settling tanks over the entire duration of the drainage event, so as to represent a composite subsample of the water being discharged. Imhoff settling cones are ultimately used to settle out the suspended particulates. This is achieved by siphoning water from the settling tanks via the cones. The particulates are then collected for physico-chemical analyses.

Large Diversity of Nonstandard Genes and Dynamic Evolution of Chloroplast Genomes in Siphonous Green Algae (Bryopsidales, Chlorophyta).

Science.gov (United States)

Cremen, Ma Chiela M; Leliaert, Frederik; Marcelino, Vanessa R; Verbruggen, Heroen

2018-04-01

Chloroplast genomes have undergone tremendous alterations through the evolutionary history of the green algae (Chloroplastida). This study focuses on the evolution of chloroplast genomes in the siphonous green algae (order Bryopsidales). We present five new chloroplast genomes, which along with existing sequences, yield a data set representing all but one families of the order. Using comparative phylogenetic methods, we investigated the evolutionary dynamics of genomic features in the order. Our results show extensive variation in chloroplast genome architecture and intron content. Variation in genome size is accounted for by the amount of intergenic space and freestanding open reading frames that do not show significant homology to standard plastid genes. We show the diversity of these nonstandard genes based on their conserved protein domains, which are often associated with mobile functions (reverse transcriptase/intron maturase, integrases, phage- or plasmid-DNA primases, transposases, integrases, ligases). Investigation of the introns showed proliferation of group II introns in the early evolution of the order and their subsequent loss in the core Halimedineae, possibly through RT-mediated intron loss.

Discriminant analysis of maintaining a vertical position in the water

Directory of Open Access Journals (Sweden)

Bratuša Zoran

2015-01-01

Full Text Available Water polo is the only sports game that takes place in the water. During the outplay, a vertical body position with the two basic mechanisms of the leg work - a breaststroke leg kick and an eggbeater leg kick, prevails. Starting from the significance of a vertical position during the game play, the methods of assessing physical preparedness of the athletes of all the categories also include the evaluation of maintaining a vertical position and consequently the load of the leg muscles. The measurements are performed during the maintenance of a vertical position (swimming in place through one of the specified mechanisms of leg work, i.e. a vertical position technique. The aim of this paper was to determine the application of different mechanisms of the leg kicks in maintaining a vertical position with young water polo players in relation to their position. The study included 29 selected junior water polo players (age_15.8 ± 0.8 years; BH_185.2 ± 5.3cm and BW_81.7 ± 7.7kg. The measurements were performed during the tests of swimming in place at the maximum intensity lasting 10 seconds, by the breaststroke and eggbeater leg kicks. The isometric tensiometry tests were used for the measurements. The results were analysed by the application of descriptive statistics, and the kinetic selection characteristic was defined by the application of discriminant analysis. Higher average values were achieved with the breaststroke leg kick technique Fmax, ImpF and RFD (avgFmaxLEGGBK =157.46±19.93N; avgImpF_LEGGBK =45.43±10.64Ns; avgRFD_LEGGBK=337.85±80.73N/s; avgFmaxLBKICK=227.18±49.17N; avgImpF_LBKICK=55.99±14.59Ns; avgRFD_LBKICK=545.47±159.15N/s. After discriminant analysis, the results have shown that the eggbeater leg kick is a selection technique, whereas the force - Fmax is a kinetic selection variable. Based on the obtained results and the analyses performed it may be concluded that a training factor dominant for maintaining a vertical position by

Overexploitation of karst spring as a measure against water scarcity.

Science.gov (United States)

Dimkić, Dejan; Dimkić, Milan; Soro, Andjelko; Pavlović, Dusan; Jevtić, Goran; Lukić, Vladimir; Svrkota, Dragan

2017-09-01

Water scarcity, especially in the hydrologically critical part of the year, is a problem often present in many cities and regions, particularly in arid and sub-arid areas. Climate change and human water demand compound the problem. This paper discusses a climate change adaptation measure-the possibility of karst spring overexploitation, where there is a siphon-shaped cavity inside the mountain. The pilot area is near the city of Niš, where a decreasing precipitation trend has already been observed and is expected to continue in the future. The paper also presents some basic information related to the pilot area and undertaken investigations. The project, successfully implemented in 2004, has provided the city of Niš with an additional amount of 200 l/s of spring water during the most critical part of the year.

The impact of fillers on lineup performance.

Science.gov (United States)

Wetmore, Stacy A; McAdoo, Ryan M; Gronlund, Scott D; Neuschatz, Jeffrey S

2017-01-01

Filler siphoning theory posits that the presence of fillers (known innocents) in a lineup protects an innocent suspect from being chosen by siphoning choices away from that innocent suspect. This mechanism has been proposed as an explanation for why simultaneous lineups (viewing all lineup members at once) induces better performance than showups (one-person identification procedures). We implemented filler siphoning in a computational model (WITNESS, Clark, Applied Cognitive Psychology 17:629-654, 2003), and explored the impact of the number of fillers (lineup size) and filler quality on simultaneous and sequential lineups (viewing lineups members in sequence), and compared both to showups. In limited situations, we found that filler siphoning can produce a simultaneous lineup performance advantage, but one that is insufficient in magnitude to explain empirical data. However, the magnitude of the empirical simultaneous lineup advantage can be approximated once criterial variability is added to the model. But this modification works by negatively impacting showups rather than promoting more filler siphoning. In sequential lineups, fillers were found to harm performance. Filler siphoning fails to clarify the relationship between simultaneous lineups and sequential lineups or showups. By incorporating constructs like filler siphoning and criterial variability into a computational model, and trying to approximate empirical data, we can sort through explanations of eyewitness decision-making, a prerequisite for policy recommendations.

Influence of salt concentration and topographical position on water ...

African Journals Online (AJOL)

Water resource quality (WRQ) is affected by salt concentration and topographical position. Indeed, an increase in salt concentration, which decreases water availability for animal and plant nutrition, and lower altitude, which diminishes the potential for production of hydropower, negatively affects WRQ. Therefore, it is useful ...

Siphon-based turbine - Demonstration project: hydropower plant at a paper factory in Perlen, Switzerland; Demonstrationsprojekt Saugheber - Turbinen. Wasserturbinenanlage Papierfabrik Perlen (WTA-PF)

Energy Technology Data Exchange (ETDEWEB)

NONE

2001-07-01

This final report for the Swiss Federal Office of Energy (SFOE) describes the demonstration project that concerned the re-activation and refurbishing of a very low-head hydropower installation. The functional principles of the siphon-turbine used are explained and the potential for its use at many low-head sites examined. The authors are of the opinion that innovative technology and simple mechanical concepts could be used to reactivate out-of-use hydropower plant or be used to refurbish existing plant to provide increased efficiency and reliability. Various other points that are to be considered when planning the refurbishment of a hydropower plant such as retaining mechanical and hydraulic symmetry in the plant are listed and concepts for reducing operating costs are discussed. Figures on the three runner-regulated turbines installed in Perlen are quoted.

Hydrodynamics of Peristaltic Propulsion

Science.gov (United States)

Athanassiadis, Athanasios; Hart, Douglas

2014-11-01

A curious class of animals called salps live in marine environments and self-propel by ejecting vortex rings much like jellyfish and squid. However, unlike other jetting creatures that siphon and eject water from one side of their body, salps produce vortex rings by pumping water through siphons on opposite ends of their hollow cylindrical bodies. In the simplest cases, it seems like some species of salp can successfully move by contracting just two siphons connected by an elastic body. When thought of as a chain of timed contractions, salp propulsion is reminiscent of peristaltic pumping applied to marine locomotion. Inspired by salps, we investigate the hydrodynamics of peristaltic propulsion, focusing on the scaling relationships that determine flow rate, thrust production, and energy usage in a model system. We discuss possible actuation methods for a model peristaltic vehicle, considering both the material and geometrical requirements for such a system.

Blind prediction of interfacial water positions in CAPRI

NARCIS (Netherlands)

Lensink, Marc F; Moal, Iain H; Bates, Paul A; Kastritis, Panagiotis L; Melquiond, Adrien S J; Karaca, Ezgi; Schmitz, Christophe; van Dijk, Marc; Bonvin, Alexandre M J J; Eisenstein, Miriam; Jiménez-García, Brian; Grosdidier, Solène; Solernou, Albert; Pérez-Cano, Laura; Pallara, Chiara; Fernández-Recio, Juan; Xu, Jianqing; Muthu, Pravin; Praneeth Kilambi, Krishna; Gray, Jeffrey J; Grudinin, Sergei; Derevyanko, Georgy; Mitchell, Julie C; Wieting, John; Kanamori, Eiji; Tsuchiya, Yuko; Murakami, Yoichi; Sarmiento, Joy; Standley, Daron M; Shirota, Matsuyuki; Kinoshita, Kengo; Nakamura, Haruki; Chavent, Matthieu; Ritchie, David W; Park, Hahnbeom; Ko, Junsu; Lee, Hasup; Seok, Chaok; Shen, Yang; Kozakov, Dima; Vajda, Sandor; Kundrotas, Petras J; Vakser, Ilya A; Pierce, Brian G; Hwang, Howook; Vreven, Thom; Weng, Zhiping; Buch, Idit; Farkash, Efrat; Wolfson, Haim J; Zacharias, Martin; Qin, Sanbo; Zhou, Huan-Xiang; Huang, Shen-You; Zou, Xiaoqin; Wojdyla, Justyna A; Kleanthous, Colin; Wodak, Shoshana J

We report the first assessment of blind predictions of water positions at protein-protein interfaces, performed as part of the critical assessment of predicted interactions (CAPRI) community-wide experiment. Groups submitting docking predictions for the complex of the DNase domain of colicin E2 and

Solvation of positive ions in water: the dominant role of water-water interaction

International Nuclear Information System (INIS)

Krekeler, Christian; Site, Luigi Delle

2007-01-01

Local polarization effects, induced by monovalent and divalent positive ions in water, influence (and in turn are influenced by) the large-scale structural properties of the solvent. Experiments can only distinguish this process of interplay in a generic qualitative way. Instead, first-principles calculations can address the question at both the electronic and atomistic scale, accounting for electronic polarization as well as geometrical conformations. For this reason we study the extension of the scales' interconnection by means of first-principle Car-Parrinello molecular dynamics applied to systems of different size. In this way we identify the general aspects dominating the physics of the first solvation shell and their connection to the effects related to the formation of the outer shells and eventually the bulk. We show that while the influence of the ions is extended to the first shell only, the water-water interaction is instead playing a dominant role even within the first shell independently of the size or the charge of the ion. (fast track communication)

A new experimental carotid siphon aneurysm model in canine based on the MR angiography and rapid prototyping technology

International Nuclear Information System (INIS)

Xie Jian; Li Minghua; Tan Huaqiao; Zhu Yueqi; Hu Dingjun; Qiao Ruihua; Fan Chunhua

2009-01-01

Objective: The aim of the experiment is to make an intracranial aneurysm model in canine. Methods: A digital tube was made based on raw magnetic resonance images of the human intracranial carotid artery. Then 6 tubes were made in the 3D rapid prototyping machine and coated with silicone. Finally we isolated the common carotid arteries of 6 canines and made them go through the tubes and anastomosed them end-to-side to get the aneurysm model. Six stents were implanted after one week. Results: Six aneurysm models were successfully made in canines. The parent artery had similar geometry of the human carotid siphon. All the aneurysms and parent arteries were patent in one week's follow-up. One canine died of excessive anesthesia after stenting. Two vascular models kept patent in one month without stenosis. The other 3 had some stenosis on the bends of the vessel. Conclusions: The aneurysm model in the experiment has high flexibility and reliability. The model provides an effective tool for research and testing neurovascular devices. It's also a useful device to train the neuroradiologists and interventional physicians. (authors)

Circulating water pumps for nuclear power stations

International Nuclear Information System (INIS)

Satoh, Hiroshi; Ohmori, Tsuneaki

1979-01-01

Shortly, the nuclear power station with unit power output of 1100 MW will begin the operation, and the circulating water pumps manufactured recently are those of 2.4 to 4 m bore, 840 to 2170 m 3 /min discharge and 2100 to 5100 kW driving power. The circulating water pumps are one of important auxiliary machines, because if they fail, power generation capacity lowers immediately. Enormous quantity of cooling water is required to cool condensers, therefore in Japan, sea water is usually used. As siphon is formed in circulating water pipes, the total head of the pumps is not very high. The discharge of the pumps is determined so as to keep the temperature rise of discharged water lower than 7 deg. C. The quantity of cooling water for nuclear power generation is about 50% more as compared with thermal power generation because of the difference in steam conditions. The total head of the pumps is normally from 8 to 15 m. The circulating water pumps rarely stop after they started the operation, therefore it is economical to determine the motor power so that it can withstand 10% overload for a short period, instead of large power. At present, vertical shaft, oblique flow circulating water pumps are usually employed. Recently, movable blade pumps are adopted. The installation, construction and materials of the pumps and the problems are described. (Kako, I.)

Treatment of carotid siphon aneurysms by use of the Willis stent graft: an angiographic and histopathological study

International Nuclear Information System (INIS)

Zhu, Yue-Qi; Li, Ming-Hua; Xie, Jian; Tan, Hua-Qiao; Wang, Jian-Bo; Cheng, Ying-Sheng

2010-01-01

We designed a carotid siphon (CS) aneurysm model in dogs to test a new stent graft (the Willis covered stent) and compared tissue reaction over 12-month follow-up versus a comparison group with stents implanted in straight vessels. Twenty-four saccular sidewall aneurysms (group A) and 12 CS aneurysms (group B) were created surgically. A Willis stent graft was implanted in each aneurysm. Angiography was performed immediately and at 1-, 3-, 6- and 12-month post-implantation to investigate aneurysm isolation, endoleak, stent angulation, parent artery (PA) patency and restenosis. Light and scanning electron microscopy were used to identify aneurysmal sac thrombi, intima hyperplasia and endothelial progress. Immediate angiography demonstrated mild endoleak in two aneurysms and three stent angulations in group B. Follow-up at 12 months revealed resolved endoleaks, occlusion in one PA and mild stenosis in three in group B. In group A, occlusion occurred in one PA and mild stenosis in two. Light microscopy revealed new intima, and all aneurysm sacs were filled with thrombi. In group B, endothelial progress was complete at 12 months, and closely correlated with haemodynamic changes. Application of a Willis stent graft is a feasible method of treating CS aneurysms, and it exhibits a prolonged endothelial progress compared with that in straight vessels. (orig.)

Ground-Based Global Positioning System (GPS) Meteorology Integrated Precipitable Water Vapor (IPW)

Data.gov (United States)

National Oceanic and Atmospheric Administration, Department of Commerce — The Ground-Based Global Positioning System (GPS) Meteorology Integrated Precipitable Water Vapor (IPW) data set measures atmospheric water vapor using ground-based...

Fast imaging of intermittent electrospraying of water with positive corona discharge

International Nuclear Information System (INIS)

Pongrác, B; Janda, M; Martišovitš, V; Machala, Z; Kim, H H

2014-01-01

The effect of the electrospraying of water in combination with a positive direct current (dc) streamer corona discharge generated in air was investigated in this paper. We employed high-speed camera visualizations and oscilloscopic discharge current measurements in combination with an intensified charge-coupled device camera for fast time-resolved imaging. The repetitive process of Taylor cone formation and droplet formation from the mass fragments of water during the electrospray was visualized. Depending on the applied voltage, the following intermittent modes of electrospraying typical for water were observed: dripping mode, spindle mode, and oscillating-spindle mode. The observed electrospraying modes were repetitive with a frequency of a few hundreds of Hz, as measured from the fast image sequences. This frequency agreed well with the frequency of the measured streamer current pulses. The presence of filamentary streamer discharges at relatively low voltages probably prevented the establishment of a continuous electrospray in the cone–jet mode. After each streamer, a positive glow corona discharge was established on the water filament tip, and it propagated from the stressed electrode along with the water filament elongation. The results show a reciprocal character of intermittent electrospraying of water, and the presence of corona discharge, where both the electrospray and the discharge affect each other. The generation of a corona discharge from the water cone depended on the repetitive process of the cone formation. Also, the propagation and curvature of the water filament were influenced by the discharge and its resultant space charge. Furthermore, these phenomena were partially influenced by the water conductivity. (paper)

Water line positions in the 782–840 nm region

International Nuclear Information System (INIS)

Hu, S.-M.; Chen, B.; Tan, Y.; Wang, J.; Cheng, C.-F.; Liu, A.-W.

2015-01-01

A set of water transitions in the 782–840 nm region, including 38 H 2 16 O lines, 12 HD 16 O lines, and 30 D 2 16 O lines, were recorded with a cavity ring-down spectrometer calibrated using precise atomic lines. Absolute frequencies of the lines were determined with an accuracy of about 5 MHz. Systematic shifts were found in the line positions given in the HITRAN database and the upper energy levels given in recent MARVEL studies. - Highlights: • Cavity ring-down spectra of H 2 16 O, HD 16 O, and D 2 16 O lines in the 782–840 nm region were measured. • Absolute line positions of 80 water lines were determined with an accuracy of about 5 MHz. • The H 2 16 O positions given in HITRAN have a systematic shift of 0.001 cm −1 in the 796–840 nm region. • MARVEL D 2 16 O energies have a systematic deviation of about −0.008 cm −1

Thermal hydraulic considerations and mock-up tests for developing two-phase thermo-siphon loop of CARR-CNS

International Nuclear Information System (INIS)

Shejiao, Du; Qincheng, Bi; Tingkuan, Chen; Quanke, Feng

2005-01-01

The main component of the China Advanced Research Reactor Cold Neutron Source (CARR-CNS), which is under design, is a two-phase thermo-siphon loop of hydrogen. It consists of a condenser, a single tube with counter current flow avoiding flooding and a cylindrical-annulus moderator cell. The mockup tests were carried out using a full-scale loop with Freon-113, to validate the self-regulating characteristics of the loop, void fraction less than 20% in the liquid of the moderator cell and the requirements for establishing the condition under which the inner shell of the moderator cell has only vapor and the outer shell liquid. In the case of these mockup tests the density ratio of liquid to vapor and the volumetric vapor evaporation rate due to heat load are kept the same as those in normal operation of the CARR-CNS. The results show that the loop has the self-regulating characteristics and the inner shell of the moderator cell contains only vapor, the outer shell liquid. The average void fraction of the moderator cell was verified less than 20% under the volumetric vapor generation of 0.65 l/s corresponding to the nuclear heating of 800 W in the case of the liquid hydrogen. The local void fraction in the liquid hydrogen increases with the increase of the loop pressure under the condition of a constant volumetric evaporation

Air pocket removal from downward sloping pipes

NARCIS (Netherlands)

Pothof, I.W.M.; Clemens, F.H.L.R.

2012-01-01

Air-water flow is an undesired condition in water pipelines and hydropower tunnels. Water pipelines and wastewater pressure mains in particular are subject to air pocket accumulation in downward sloping reaches, such as inverted siphons or terrain slopes. Air pockets cause energy losses and an

Measurement and inference of profile soil-water dynamics at different hillslope positions in a semiarid agricultural watershed

Science.gov (United States)

Green, Timothy R.; Erskine, Robert H.

2011-12-01

Dynamics of profile soil water vary with terrain, soil, and plant characteristics. The objectives addressed here are to quantify dynamic soil water content over a range of slope positions, infer soil profile water fluxes, and identify locations most likely influenced by multidimensional flow. The instrumented 56 ha watershed lies mostly within a dryland (rainfed) wheat field in semiarid eastern Colorado. Dielectric capacitance sensors were used to infer hourly soil water content for approximately 8 years (minus missing data) at 18 hillslope positions and four or more depths. Based on previous research and a new algorithm, sensor measurements (resonant frequency) were rescaled to estimate soil permittivity, then corrected for temperature effects on bulk electrical conductivity before inferring soil water content. Using a mass-conservation method, we analyzed multitemporal changes in soil water content at each sensor to infer the dynamics of water flux at different depths and landscape positions. At summit positions vertical processes appear to control profile soil water dynamics. At downslope positions infrequent overland flow and unsaturated subsurface lateral flow appear to influence soil water dynamics. Crop water use accounts for much of the variability in soil water between transects that are either cropped or fallow in alternating years, while soil hydraulic properties and near-surface hydrology affect soil water variability across landscape positions within each management zone. The observed spatiotemporal patterns exhibit the joint effects of short-term hydrology and long-term soil development. Quantitative methods of analyzing soil water patterns in space and time improve our understanding of dominant soil hydrological processes and provide alternative measures of model performance.

Process for cooling waste water

Energy Technology Data Exchange (ETDEWEB)

Rohner, P

1976-12-16

The process for avoiding thermal pollution of waters described rests on the principle of the heat conduction tube, by which heat is conducted from the liquid space into the atmosphere at a lower temperature above it. Such a tube, here called a cooling tube, consists in its simplest form of a heat conducting corrugated tube, made, for example, of copper or a copper alloy or of precious metals, which is sealed to be airtight at both ends, and after evacuation, is partially filled with a medium of low boiling point. The longer leg of the tube, which is bent at right angles, lies close below the surface of the water to be cooled and parallel to it; the shorter leg projects vertically into the atmosphere. The liquid inside the cooling tube fills the horizontal part of the tube to about halfway. A certain part of the liquid is always evaporated in this part. The vapor rising in the vertical part of the tube condenses on the internal wall cooled by the air outside, and gives off its heat to the atmosphere. The condensed medium flows back down the vertical internal wall into the initial position in a continuous cycle. A further development contains a smooth plastic inner tube in an outer corrugated tube, which is shorter than the outer tube; it ends at a distance from the caps sealing the outer tube at both ends. In this design the angle between the vertical and horizontal leg is less than 90/sup 0/. The shorter leg projects vertically from the water surface, below which the longer leg rises slightly from the knee of tube. The quantity of the liquid is gauged as a type of siphon, so that the space between the outer and inner tube at the knee of the tube remains closed by the liquid medium. The medium evaporated from the surface in the long leg of the tube therefore flows over the inner tube, which starts above the level of the medium. Thus evaporation and condensation paths are separated.

Computational Studies of Positive and Negative Streamers in Bubbles Suspended in Distilled Water

KAUST Repository

Sharma, Ashish

2017-01-05

We perform computational studies of nanosecond streamers generated in helium bubbles immersed in distilled water under high pressure conditions. The model takes into account the presence of water vapor in the gas bubble for an accurate description of the chemical kinetics of the discharge. We apply positive and negative trigger voltages much higher than the breakdown voltage and study the dynamic characteristics of the resulting discharge. We observe that, for high positive trigger voltages, the streamer moves along the surface of the gas bubble during the initial stages of the discharge. We also find a considerable difference in the evolution of the streamer discharge for positive and negative trigger voltages with more uniform volumetric distribution of species in the streamer channel for negative trigger voltages due to formation of multiple streamers. We also observe that the presence of water vapor does not influence the breakdown voltage of the discharge but greatly affects the composition of dominant species in the trail of the streamer channel.

Mineralizing urban net-zero water treatment: Field experience for energy-positive water management.

Science.gov (United States)

Wu, Tingting; Englehardt, James D

2016-12-01

An urban net-zero water treatment system, designed for energy-positive water management, 100% recycle of comingled black/grey water to drinking water standards, and mineralization of hormones and other organics, without production of concentrate, was constructed and operated for two years, serving an occupied four-bedroom, four-bath university residence hall apartment. The system comprised septic tank, denitrifying membrane bioreactor (MBR), iron-mediated aeration (IMA) reactor, vacuum ultrafilter, and peroxone or UV/H 2 O 2 advanced oxidation, with 14% rainwater make-up and concomitant discharge of 14% of treated water (ultimately for reuse in irrigation). Chemical oxygen demand was reduced to 12.9 ± 3.7 mg/L by MBR and further decreased to below the detection limit (treatment. The process produced a mineral water meeting 115 of 115 Florida drinking water standards that, after 10 months of recycle operation with ∼14% rainwater make-up, had a total dissolved solids of ∼500 mg/L, pH 7.8 ± 0.4, turbidity 0.12 ± 0.06 NTU, and NO 3 -N concentration 3.0 ± 1.0 mg/L. None of 97 hormones, personal care products, and pharmaceuticals analyzed were detected in the product water. For a typical single-home system with full occupancy, sludge pumping is projected on a 12-24 month cycle. Operational aspects, including disinfection requirements, pH evolution through the process, mineral control, advanced oxidation by-products, and applicability of point-of-use filters, are discussed. A distributed, peroxone-based NZW management system is projected to save more energy than is consumed in treatment, due largely to retention of wastewater thermal energy. Recommendations regarding design and operation are offered. Copyright © 2016 Elsevier Ltd. All rights reserved.

Natural organic matter removal by ion exchange at different positions in the drinking water treatment lane

Directory of Open Access Journals (Sweden)

A. Grefte

2013-01-01

Full Text Available To guarantee a good water quality at the customers tap, natural organic matter (NOM should be (partly removed during drinking water treatment. The objective of this research was to improve the biological stability of the produced water by incorporating anion exchange (IEX for NOM removal. Different placement positions of IEX in the treatment lane (IEX positioned before coagulation, before ozonation or after slow sand filtration and two IEX configurations (MIEX® and fluidized IEX (FIX were compared on water quality as well as costs. For this purpose the pre-treatment plant at Loenderveen and production plant Weesperkarspel of Waternet were used as a case study. Both, MIEX® and FIX were able to remove NOM (mainly the HS fraction to a high extent. NOM removal can be done efficiently before ozonation and after slow sand filtration. The biological stability, in terms of assimilable organic carbon, biofilm formation rate and dissolved organic carbon, was improved by incorporating IEX for NOM removal. The operational costs were assumed to be directly dependent of the NOM removal rate and determined the difference between the IEX positions. The total costs for IEX for the three positions were approximately equal (0.0631 € m−3, however the savings on following treatment processes caused a cost reduction for the IEX positions before coagulation and before ozonation compared to IEX positioned after slow sand filtration. IEX positioned before ozonation was most cost effective and improved the biological stability of the treated water.

College Cafeteria Signage Increases Water Intake but Water Position on the Soda Dispenser Encourages More Soda Consumption.

Science.gov (United States)

Montuclard, Astrid Linn; Park-Mroch, Jennifer; O'Shea, Amy M J; Wansink, Brian; Irvin, Jill; Laroche, Helena H

2017-10-01

To evaluate the effects of improved water location visibility and water dispenser position on the soda dispenser on undergraduate students' beverage choices. Two focus groups with pilot intervention surveys before and after, adding a small sign above the soda dispensers' water button for 6 weeks in a large US university's all-you-can-eat, prepaid dining hall (measured with chi-square tests and logistic and ordinal logistic regression). Focus groups included 15 students. Survey participants included 357 students before and 301 after the intervention. After the intervention, more students reported ever having drunk water with the meal (66.4% to 77.0%; P = .003) and water consumption frequency increased (P = .005). Postintervention, the odds of drinking water increased by 1.57. Preference for other drinks was the main reason for not drinking water. A total of 59% of students had ever changed their preference from water to soda. The clear indication of the water's location increased students' reported water consumption. Further investigation is needed into how a non-independent water dispenser influences students' beverage choice. Clearly labeled, independent water dispensers are recommended. Copyright © 2017 Society for Nutrition Education and Behavior. All rights reserved.

Helicopter crashes into water: warning time, final position, and other factors affecting survival.

Science.gov (United States)

Brooks, Christopher J; MacDonald, Conor V; Baker, Susan P; Shanahan, Dennis F; Haaland, Wren L

2014-04-01

According to 40 yr of data, the fatality rate for a helicopter crash into water is approximately 25%. Does warning time and the final position of the helicopter in the water influence the survival rate? The National Transportation Safety Board (NTSB) database was queried to identify helicopter crashes into water between 1981 and 2011 in the Gulf of Mexico and Hawaii. Fatality rate, amount of warning time prior to the crash, and final position of the helicopter were identified. There were 133 helicopters that crashed into water with 456 crew and passengers. Of these, 119 occupants (26%) did not survive; of those who did survive, 38% were injured. Twelve died after making a successful escape from the helicopter. Crashes with 1 min. However, more than half of fatalities (57%) came from crashes for which the warning time could not be determined. Lack of warning time and how to survive in the water after the crash should be a topic for study in all marine survival/aircraft ditching courses. Investigators should be trained to provide estimates of warning time when investigating helicopter crashes into water.

Micro-distribution of freshwater snails before and after water flow ...

African Journals Online (AJOL)

Bulinus truncatus the intermediate host of Schistosoma haematobium, is widely distributed in modern irrigation schemes in Morocco. These schemes have intermittent irrigation and canals dry out in between irrigation periods. The snail species is therefore associated with the 'siphon boxes' connecting canal segments, ...

Quantitative assessment of Azumiobodo hoyamushi distribution in the tunic of soft tunic syndrome-affected ascidian Halocynthia roretzi using real-time polymerase chain reaction.

Science.gov (United States)

Shin, Yun-Kyung; Nam, Ki-Woong; Park, Kwan Ha; Yoon, Jong-Man; Park, Kyung-Il

2014-11-26

The kinetoplastid parasite, Azumiobodo hoyamushi, is the causative agent of soft tunic syndrome (STS) in ascidians and leads to their mass mortality in Korean waters. This study was conducted to quantify A. hoyamushi density during the development of STS in the tunics of ascidians (Halocynthia roretzi) using real-time polymerase chain reaction (qPCR). The infection intensity of A. hoyamushi, as measured by qPCR, varied depending on the part of the tunic analyzed, as well as the stage of STS development. The highest infection intensity was recorded in the tunics of the siphons. The infection intensity of A. hoyamushi in the siphons was only 2.9 cell/tunic (area, 0.25 cm(2)) or 106.0 cell/gram tunic (GT) in the early phase of STS, but this value increased dramatically to 16,066 cells/tunic (0.25 cm(2)) or 617,004 cell/GT at the time of death. The number of A. hoyamushi parasites increased gradually and their distribution spread from the siphons to the other parts of the tunics. qPCR enabled the quantitation of A. hoyamushi and the results revealed that parasite density increased as STS progressed. In addition, our results suggested that the siphons might function as the portal of entry for A. hoyamushi during infection.

Social Position Influencing the Water Perception Gap Between Local Leaders and Constituents in a Socio-Hydrological System

Science.gov (United States)

Haeffner, Melissa; Jackson-Smith, Douglas; Flint, Courtney G.

2018-02-01

How well city leaders represent their constituents and meet their needs are key concerns in transitioning to local sustainable water governance. To date, however, there is little research documenting the influence of social position between elected leaders who make policy, career staff water managers who design and operate systems and implement policies, and the members of the public whose individual water use behaviors are important drivers of water sustainability outcomes. In this study, we ask: "How does social position explain variation in water perceptions and concerns between different actors in a socio-hydrological system?" Using a mixed method approach with survey and interview data, we explore the ways that positioning within the governance system, geographic context, and citizen engagement in local government mediate perceptions of the urban water system. Regardless of local biophysical water supply conditions, residents showed most concern about future water shortages and high water costs, while their leaders were consistently most concerned about deteriorating local water infrastructure. Further, constituents who received water-related information directly from public utility mailings or served on community committees and boards had perceptions that were more aligned with leaders' concerns. The importance of social structure over natural and built environments in shaping water issue perceptions underscores the value of social analysis in socio-hydrology studies. Further, practitioners looking to increase consensus for a transition to sustainable water governance might work to develop institutional mechanisms to increase opportunities for water user involvement in local water system governance.

Exploring the Legionella pneumophila positivity rate in hotel water samples from Antalya, Turkey.

Science.gov (United States)

Sepin Özen, Nevgün; Tuğlu Ataman, Şenay; Emek, Mestan

2017-05-01

The genus Legionella is a fastidious Gram-negative bacteria widely distributed in natural waters and man made water supply systems. Legionella pneumophila is the aetiological agent of approximately 90% of reported Legionellosis cases, and serogroup 1 is the most frequent cause of infections. Legionnaires' disease is often associated with travel and continues to be a public health concern at present. The correct water management quality practices and rapid methods for analyzing Legionella species in environmental water is a key point for the prevention of Legionnaires' disease outbreaks. This study aimed to evaluate the positivity rates and serotyping of Legionella species from water samples in the region of Antalya, Turkey, which is an important tourism center. During January-December 2010, a total of 1403 samples of water that were collected from various hotels (n = 56) located in Antalya were investigated for Legionella pneumophila. All samples were screened for L. pneumophila by culture method according to "ISO 11731-2" criteria. The culture positive Legionella strains were serologically identified by latex agglutination test. A total of 142 Legionella pneumophila isolates were recovered from 21 (37.5%) of 56 hotels. The total frequency of L. pneumophila isolation from water samples was found as 10.1%. Serological typing of 142 Legionella isolates by latex agglutination test revealed that strains belonging to L. pneumophila serogroups 2-14 predominated in the examined samples (85%), while strains of L. pneumophila serogroup 1 were less numerous (15%). According to our knowledge, our study with the greatest number of water samples from Turkey demonstrates that L. pneumophila serogroups 2-14 is the most common isolate. Rapid isolation of L. pneumophila from environmental water samples is essential for the investigation of travel related outbreaks and the possible resources. Further studies are needed to have epidemiological data and to determine the types of L

Laboratory experiments on the transfer dynamics of plutonium from marine sediments to sea water and to marine organisms

International Nuclear Information System (INIS)

Mo, T.; Lowman, F.G.

1975-01-01

The leachability of 239 240 Pu from a fine contaminated calcareous sediment to aerated open sea water and to anoxic sea water was measured. The distribution coefficient for 239 240 Pu from sediment to sea water was 6.1 x 10 -5 for aerated water and 2.6 x 10 -6 for anoxic water. Experiments on the uptake of 239 240 Pu by the clams Donax denticulatus, and Lucina pectinata, were done in aquaria containing kilogram quantities of sediment from the Bravo Crater at Bikini Atoll. The concentration factor for 239 240 Pu by the soft parts of these clams was about 200. All the plutonium taken up in the soft parts was associated with the gill, mantle and siphon. No plutonium was detected in the adductor muscles or hepatopancreas. The smooth surfaces of the shells of the Donax did not show any detectable plutonium, but the rough shell surfaces of the Lucina concentrated plutonium by a factor of 1.10 x 10 4 over that in the sea water. Marine periphyton cultured on glass plates in an aquarium concentrated 239 240 Pu by a factor of about 7 x 10 3 over that in the sea water. (U.S.)

New approach for control rod position indication system for light water power reactor

International Nuclear Information System (INIS)

Bahuguna, Sushil; Dhage, Sangeeta; Nawaj, S.; Salek, C.; Lahiri, S.K.; Marathe, P.P.; Mukhopadhyay, S.; Taly, Y.K.

2015-01-01

Control rod position indication system is an important system in a nuclear power plant to monitor and display control rod position in all regimes of reactor operation. A new approach to design a control rod position indication system for sensing absolute position of control rod in Light Water Power Reactor has been undertaken. The proposed system employs an inductive type, hybrid measurement strategy providing both analog position as well as digital zone indication with built-in temperature compensation. The new design approach meets single failure criterion through redundancy in design without sacrificing measurement resolution. It also provides diversity in measurement technique by indirect position sensing based on analysis of drive coil current signature. Prototype development and qualification at room temperature of the control rod position indication system (CRPIS) has been demonstrated. The article presents the design philosophy of control rod position indication system, the new measurement strategy for sensing absolute position of control rod, position estimation algorithm for both direct and indirect sensing and a brief account associated processing electronics. (author)

Microbiological effectiveness of household water treatment technologies under field use conditions in rural Tanzania.

Science.gov (United States)

Mohamed, Hussein; Clasen, Thomas; Njee, Robert Mussa; Malebo, Hamisi M; Mbuligwe, Stephen; Brown, Joe

2016-01-01

To assess the microbiological effectiveness of several household water treatment and safe storage (HWTS) options in situ in Tanzania, before consideration for national scale-up of HWTS. Participating households received supplies and instructions for practicing six HWTS methods on a rotating 5-week basis. We analysed 1202 paired samples (source and treated) of drinking water from 390 households, across all technologies. Samples were analysed for thermotolerant (TTC) coliforms, an indicator of faecal contamination, to measure effectiveness of treatment in situ. All HWTS methods improved microbial water quality, with reductions in TTC of 99.3% for boiling, 99.4% for Waterguard ™ brand sodium hypochlorite solution, 99.5% for a ceramic pot filter, 99.5% for Aquatab ® sodium dichloroisocyanurate (NaDCC) tablets, 99.6% for P&G Purifier of Water ™ flocculent/disinfectant sachets, and 99.7% for a ceramic siphon filter. Microbiological performance was relatively high compared with other field studies and differences in microbial reductions between technologies were not statistically significant. Given that microbiological performance across technologies was comparable, decisions regarding scale-up should be based on other factors, including uptake in the target population and correct, consistent, and sustained use over time. © 2015 John Wiley & Sons Ltd.

Soil hydrology of agroforestry systems: Competition for water or positive tree-crops interactions?

Science.gov (United States)

Gerjets, Rowena; Richter, Falk; Jansen, Martin; Carminati, Andrea

2017-04-01

In dry periods during the growing season crops may suffer from severe water stress. The question arises whether the alternation of crop and tree strips might enhance and sustain soil water resources available for crops during drought events. Trees reduce wind exposure, decreasing the potential evapotranspiration of crops and soils; additionally hydraulic lift from the deep roots of trees to the drier top soil might provide additional water for shallow-rooted crops. To understand the above and belowground water relations of agroforestry systems, we measured soil moisture and soil water potential in crop strips as a function of distance to the trees at varying depth as well as meteorological parameters. At the agroforestry site Reiffenhausen, Lower Saxony, Germany, two different tree species are planted, each in one separated tree strip: willow breed Tordis ((Salix viminalis x Salix Schwerinii) x Salix viminalis) and poplar clone Max 1 (Populus nigra x Populus maximowiczii). In between the tree strips a crop strip of 24 m width was established with annual crop rotation, managed the same way as the reference site. During a drought period in May 2016 with less than 2 mm rain in four weeks, an overall positive effect on hydrological conditions of the agroforestry system was observed. The results show that trees shaded the soil surface, lowering the air temperature and further increasing the soil moisture in the crop strips compared to the reference site, which was located far from the trees. At the reference site the crops took up water in the upper soil (sunlight. The two tree species behaved differently. The poplar strips showed more marked diurnal changes in soil water potential, with fast drying during daytime and rewetting during nighttime. We suppose that the rewetting during nighttime was caused by hydraulic lift, which supports passively the drier upper soil with water from the wetter, lower soil layers. This experimental study shows the importance of above- and

Necessary and sufficient liveness condition of GS3PR Petri nets

Science.gov (United States)

Liu, GaiYun; Barkaoui, Kamel

2015-05-01

Structural analysis is one of the most important and efficient methods to investigate the behaviour of Petri nets. Liveness is a significant behavioural property of Petri nets. Siphons, as structural objects of a Petri net, are closely related to its liveness. Many deadlock control policies for flexible manufacturing systems (FMS) modelled by Petri nets are implemented via siphon control. Most of the existing methods design liveness-enforcing supervisors by adding control places for siphons based on their controllability conditions. To compute a liveness-enforcing supervisor with as much as permissive behaviour, it is both theoretically and practically significant to find an exact controllability condition for siphons. However, the existing conditions, max, max‧, and max″-controllability of siphons are all overly restrictive and generally sufficient only. This paper develops a new condition called max*-controllability of the siphons in generalised systems of simple sequential processes with resources (GS3PR), which are a net subclass that can model many real-world automated manufacturing systems. We show that a GS3PR is live if all its strict minimal siphons (SMS) are max*-controlled. Compared with the existing conditions, i.e., max-, max‧-, and max″-controllability of siphons, max*-controllability of the SMS is not only sufficient but also necessary. An example is used to illustrate the proposed method.

Plant roots use a patterning mechanism to position lateral root branches toward available water.

Science.gov (United States)

Bao, Yun; Aggarwal, Pooja; Robbins, Neil E; Sturrock, Craig J; Thompson, Mark C; Tan, Han Qi; Tham, Cliff; Duan, Lina; Rodriguez, Pedro L; Vernoux, Teva; Mooney, Sacha J; Bennett, Malcolm J; Dinneny, José R

2014-06-24

The architecture of the branched root system of plants is a major determinant of vigor. Water availability is known to impact root physiology and growth; however, the spatial scale at which this stimulus influences root architecture is poorly understood. Here we reveal that differences in the availability of water across the circumferential axis of the root create spatial cues that determine the position of lateral root branches. We show that roots of several plant species can distinguish between a wet surface and air environments and that this also impacts the patterning of root hairs, anthocyanins, and aerenchyma in a phenomenon we describe as hydropatterning. This environmental response is distinct from a touch response and requires available water to induce lateral roots along a contacted surface. X-ray microscale computed tomography and 3D reconstruction of soil-grown root systems demonstrate that such responses also occur under physiologically relevant conditions. Using early-stage lateral root markers, we show that hydropatterning acts before the initiation stage and likely determines the circumferential position at which lateral root founder cells are specified. Hydropatterning is independent of endogenous abscisic acid signaling, distinguishing it from a classic water-stress response. Higher water availability induces the biosynthesis and transport of the lateral root-inductive signal auxin through local regulation of tryptophan aminotransferase of Arabidopsis 1 and PIN-formed 3, both of which are necessary for normal hydropatterning. Our work suggests that water availability is sensed and interpreted at the suborgan level and locally patterns a wide variety of developmental processes in the root.

Comparison of Water, Mannitol and Positive Oral Contrast for Evaluation of Bowel By Computed Tomography

Directory of Open Access Journals (Sweden)

Padhmanaban Elamparidhi

2017-10-01

Full Text Available Introduction: Small bowel remains a challenging anatomical site. Imaging approaches like CT-enterography helps in diagnosing non specific clinical presentations and imaging aids in appropriate management. Hence, bowel evaluation by CT requires a oral contrast agent for diagnosing the bowel pathology. Thus, quantitative and qualitative analysis of three oral contrast agents i.e., water, mannitol and positive contrast was done for identification of ideal intraluminal contrast agent. Aim: To assess the performance of mannitol as an endoluminal contrast agent as compared to water and positive contrast in the evaluation of bowel, to compare the distention of bowel with different oral contrasts and also to assess the usefulness of bowel distension in assessment of mural enhancement pattern of bowel. Materials and Methods: A comparative observational study was performed which consisted of 75 patients who were divided into three groups of 25 patients each. Patients in each group were given 1500 ml of oral contrast. Group I was given mannitol, Group II was given water and Group III was given positive contrast. Assessments of bowel distention at various levels and mural enhancement of bowel were studied. Chisquare test was used as test of significance for qualitative data. ANOVA (Analysis of Variance was the test of significance for quantitative data. Results: Bowel distention was excellent in mannitol compared to water and positive contrast. Wall enhancement and mural pattern was better appreciated with mannitol compared to other two contrast agents. Conclusion: Adequate bowel evaluation by CT requires an oral contrast agent which can cause maximal bowel distention, uniform intraluminal attenuation, increased contrast between intraluminal content and bowel wall with no artifacts and adverse effects. Mannitol has all the above characteristic and can be used as ideal neutral oral contrast agent.

Observing Tropospheric Water Vapor by Radio Occultation using the Global Positioning System

Science.gov (United States)

Kursinski, E. R.; Hajj, G. A.; Hardy, K. R.; Romans, L. J.; Schofield, J. T.

1995-01-01

Given the importance of water vapor to weather, climate and hydrology, global humidity observations from satellites are critical. At low latitudes, radio occultation observations of Earth's atmosphere using the Global Positioning System (GPS) satellites allow water vapor profiles to be retrieved with accuracies of 10 to 20% below 6 to 7 km altitude and approx. 5% or better within the boundary layer. GPS observations provide a unique combination of accuracy, vertical resolution (less than or equal to 1 km) and insensitivity to cloud and aerosol particles that is well suited to observations of the lower troposphere. These characteristics combined with the inherent stability of radio occultation observations make it an excellent candidate for the measurement of long term trends.

The effect of blood sample positions in a water phantom at the time of irradiation on the dicentric yield

International Nuclear Information System (INIS)

Inoue, Yoshinori

1995-01-01

Blood samples of man and rabbit, placed at various distances from the surface of a water phantom with a dosimeter were exposed to 250mGy of 60 Co γ-rays. Increases in the dicentric yields in the lymphocytes were observed with increased distances from the surface of the water phantom. As a variation of the dicentric yield with increasing distance in water was found, in the experiment to obtain calibration curves for biological dosimetry, it is recommended that blood samples should be positioned at a constant distance from the surface of a water phantom at the time of irradiation. ICRU REPORT 23 recommends that the calibration measurement be carried out with an ionization chamber positioned at 5cm depth below the surface of a water phantom for 150 kV-10 MV X rays, and 137 Cs and 60 Co γ-rays. As the same reasons which determine a 5cm depth in the recommendation, should be applied to this case, it is desirable that the experiment be carried out with blood samples positioned at 5cm distance from the surface of a water phantom. (author)

Thermodynamic analysis of a new design of temperature controlled parabolic trough collector

International Nuclear Information System (INIS)

Ceylan, İlhan; Ergun, Alper

2013-01-01

Highlights: • This new design parabolic trough collector has been made as temperature control. • The TCPTC system is very appropriate for the industrial systems which require high temperatures. • With TCPTC can provide hot water with low solar radiation. • TCPTC system costs are cheaper than other systems (thermo siphon systems, pomp systems, etc.). - Abstract: Numerous types of solar water heater are used throughout the world. These heaters can be classified into two groups as pumped systems and thermo siphon systems. However, water temperature cannot be controlled by these systems. In this study, a new temperature-controlled parabolic trough collector (TCPTC) was designed and analyzed experimentally. The analysis was made at a temperature range of 40–100 °C, with at intervals of 10 °C. A detailed analysis was performed by calculating energy efficiencies, exergy efficiencies, water temperatures and water amounts. The highest energy efficiency of TCPTC was calculated as 61.2 for 100 °C. As the set temperature increased, the energy efficiency increased as well. The highest exergy efficiency was calculated as 63 for 70 °C. However, as the set temperature increased, the exergy efficiency did not increase. Optimum exergy efficiency was obtained for 70 °C

Drinking Water Quality, Feeding Practices, and Diarrhea among Children under 2 Years of HIV-Positive Mothers in Peri-Urban Zambia

Science.gov (United States)

Peletz, Rachel; Simuyandi, Michelo; Sarenje, Kelvin; Baisley, Kathy; Kelly, Paul; Filteau, Suzanne; Clasen, Thomas

2011-01-01

In low-income settings, human immunodeficiency virus (HIV)-positive mothers must choose between breastfeeding their infants and risking transmission of HIV or replacement feeding their infants and risking diarrheal disease from contaminated water. We conducted a cross-sectional study of children water samples. In a multivariable analysis, factors associated with diarrhea prevalence in children water in the past 2 days (aOR = 4.08, 95% CI = 1.07–15.52), child never being breastfed (aOR = 2.67, 95% CI = 1.06–6.72), and rainy (versus dry) season (aOR = 4.60, 95% CI = 1.29–16.42). Children born to HIV-positive mothers were exposed to contaminated water through direct intake of drinking water, indicating the need for interventions to ensure microbiological water quality. PMID:21813854

Mechanism of Electromagnetic Energy Effects of the Nervous System. Experimental System and Preliminary Results.

Science.gov (United States)

1982-07-01

ESOPHAGUS ABDOMINAL GANG LION SIPHON NERVE .. . BRANCHIAL NERVE ANTERIOR GIZZARD " GENITAL NERVE SPERMATHECA BRANCHIAL GANGLION GENITAL GANGLION -4HAPTO...12 LEFT CONNECTIVE RIGHT CONNECTIVE SIPHON NERVELS9 GENITAL- BRANCHIAL PERICARDIAL NERVE NERVEI ~-.- 1MM-s RIGHT CONNECTIVE LEFT CONNECTIVE VPN...SIPHON LIO NERVE BRANCHIAL GNTL NERVE PERICARDIAL NERVE Figure 4. Map of identified neurons in the abdominal ganglion of Aplyuia californica. *13 was re

A water heating system analysis for rural residences, using solar energy; Analise de um sistema de aquecimento de agua para residencias rurais, utilizando energia solar

Energy Technology Data Exchange (ETDEWEB)

Basso, Luiz H.; Souza, Samuel N.M. de; Siqueira, Jair A.C.; Nogueira, Carlos E.C.; Santos, Reginaldo F. [Universidade Estadual do Oeste do Parana (UNIOESTE), Cascavel, PR (Brazil). Programa de Pos-Graduacao em Engenharia Agricola], emails: melegsouza@yahoo.com, ssouza@unioeste.br, jairsiqueira@unioeste.br, cecn1@yahoo.com.br, rfsantos@unioeste.br

2010-01-15

The awareness of the importance of the environment has stimulated the study of new renewed energy sources and less pollutant. Amongst these sources, solar energy stands alone for being perennial and clean. The use of solar energy in systems of agricultural residential water heating, can complement the economy of electric energy, base of the Brazilian energy matrix. Knowing the factors that influence the operation of a system of water heating by solar energy is important in determining their technical viabilities targeting their distribution in agricultural residences. To evaluate equipment of water heating for solar energy, a prototype was constructed in the campus of Assis Gurgacz College, in Cascavel,State of Parana, Brazil, with similar characteristics to equipment used in residences for two inhabitants, to function with natural circulation or thermo siphon and without help of a complementary heating system. The equipment revealed technical viability, reaching the minimum temperature for shower, of 35 deg C, whenever the solar radiation was above the 3,500 Wh m{sup -2}, for the majority of the studied days. (author)

The Life of a Sponge in a Sandy Lagoon.

Science.gov (United States)

Ilan, M; Abelson, A

1995-12-01

Infaunal soft-bottom invertebrates benefit from the presence of sediment, but sedimentation is potentially harmful for hard-bottom dwellers. Most sponges live on hard bottom, but on coral reefs in the Red Sea, the species Biemna ehrenbergi (Keller, 1889) is found exclusively in soft-bottom lagoons, usually in the shallowest part. This location is a sink environment, which increases the deposition of particulate organic matter. Most of the sponge body is covered by sediment, but the chimney-like siphons protrude from the sediment surface. The sponge is attached to the buried beach-rock, which reduces the risk of dislodgment during storms. Dye injected above and into the sediment revealed, for the first time, a sponge pumping interstitial water (rich with particles and nutrients) into its aquiferous system. Visual examination of plastic replicas of the aquiferous system and electron microscopical analysis of sponge tissue revealed that the transcellular ostia are mostly located on the buried surface of the sponge. The oscula, however, are located on top of the siphons; their elevated position and their ability to close combine to prevent the filtering system outflow from clogging. The transcellular ostia presumably remain open due to cellular mobility. The sponge maintains a large population of bacteriocytes, which contains bacteria of several different species. Some of these bacteria disintegrate, and may be consumed by the sponge.

Particle Image Velocimetry (PIV) Measurements of Suspension-Feeding Velocities

Science.gov (United States)

Du Clos, K.; Jones, I. T.; Carrier, T. J.; Jumars, P. A.

2016-02-01

Active suspension feeders, such as bivalves and tunicates, connect benthic and pelagic ecosystems by packaging suspended matter into larger fecal and pseudofecal particles, greatly enhancing the flux of carbon and nutrients from the water column to the benthos. The volume of water processed by a population of suspension feeders is commonly estimated by scaling up results from experiments that measure the clearance rate (the volume of water cleared of particles per time) of one or a few individual suspension feeders. Clearance rates vary, however, between species, within a species, and over time for a single individual; and the velocity fields produced by suspension feeders are likely to interact in complex ways. We measured the water velocity fields produced by two species of bivalve, Mya arenaria and Mercenaria mercenaria, and the tunicate Ciona intestinalis, using particle image velocimetry (PIV). We used these measurements to calculate flow rates and Reynolds numbers of inhalant and exhalant siphons. We also observed strong entrainment of water by M. arenaria's exhalant siphon jet that may help to explain how the clam avoids depleting the water around it of particles and oxygen as it feeds. We are using these measurements to inform computational fluid mechanics (CFD) models of suspension feeding, allowing us to examine the interactions of flow fields produced by multiple suspension feeders and other effects not quantified by clearance-rate measurements.

Manila clams from Hg polluted sediments of Marano and Grado lagoons (Italy) harbor detoxifying Hg resistant bacteria in soft tissues

International Nuclear Information System (INIS)

Baldi, Franco; Gallo, Michele; Marchetto, Davide; Faleri, Claudia; Maida, Isabel; Fani, Renato

2013-01-01

A mechanism of mercury detoxification has been suggested by a previous study on Hg bioaccumulation in Manila clams (Ruditapes philippinarum) in the polluted Marano and Grado lagoons and in this study we demonstrate that this event could be partly related to the detoxifying activities of Hg-resistant bacteria (MRB) harbored in clam soft tissues. Therefore, natural clams were collected in six stations during two different periods (winter and spring) from Marano and Grado Lagoons. Siphons, gills and hepatopancreas from acclimatized clams were sterile dissected to isolate MRB. These anatomical parts were glass homogenized or used for whole, and they were lying on a solid medium containing 5 mg l −1 HgCl 2 and incubated at 30 °C. A total of fourteen bacterial strains were isolated and were identified by 16S rDNA sequencing and analysis, revealing that strains were representative of eight bacterial genera, four of which were Gram-positive (Enterococcus, Bacillus, Jeotgalicoccus and Staphylococcus) and other four were Gram-negative (Stenotrophomonas, Vibrio, Raoultella and Enterobacter). Plasmids and merA genes were found and their sequences determined. Fluorescence in situ hybridization (FISH) technique shows the presence of Firmicutes, Actinobacteria and Gammaproteobacteria by using different molecular probes in siphon and gills. Bacterial clumps inside clam flesh were observed and even a Gram-negative endosymbiont was disclosed by transmission electronic microscope inside clam cells. Bacteria harbored in cavities of soft tissue have mercury detoxifying activity. This feature was confirmed by the determination of mercuric reductase in glass-homogenized siphons and gills. -- Highlights: ► We isolated Gram-positive and Gram-negative Hg resistant strains from soft tissues of Ruditapes philippinarum. ► We identify 14 mercury resistant strains by 16S rRNA gene sequences. ► Bacteria in siphon and gill tissues of clams were observed by TEM and identified with

Manila clams from Hg polluted sediments of Marano and Grado lagoons (Italy) harbor detoxifying Hg resistant bacteria in soft tissues

Energy Technology Data Exchange (ETDEWEB)

Baldi, Franco [Dipartimento di Scienze Molecolari e Nanosistemi, Cà Foscari University of Venice, Dorsoduro 2137, 30123 Venice (Italy); Gallo, Michele; Marchetto, Davide [Dipartimento di Scienze Molecolari e Nanosistemi, Cà Foscari University of Venice, Dorsoduro 2137, 30123 Venice (Italy); Faleri, Claudia [Department of Environmental Science ‘G. Sarfatti’, University of Siena, 53100 Siena (Italy); Maida, Isabel; Fani, Renato [Dipartimento di Biologia Evoluzionistica, Via Romana, 17, University of Florence, 50125 Florence (Italy)

2013-08-15

A mechanism of mercury detoxification has been suggested by a previous study on Hg bioaccumulation in Manila clams (Ruditapes philippinarum) in the polluted Marano and Grado lagoons and in this study we demonstrate that this event could be partly related to the detoxifying activities of Hg-resistant bacteria (MRB) harbored in clam soft tissues. Therefore, natural clams were collected in six stations during two different periods (winter and spring) from Marano and Grado Lagoons. Siphons, gills and hepatopancreas from acclimatized clams were sterile dissected to isolate MRB. These anatomical parts were glass homogenized or used for whole, and they were lying on a solid medium containing 5 mg l{sup −1} HgCl{sub 2} and incubated at 30 °C. A total of fourteen bacterial strains were isolated and were identified by 16S rDNA sequencing and analysis, revealing that strains were representative of eight bacterial genera, four of which were Gram-positive (Enterococcus, Bacillus, Jeotgalicoccus and Staphylococcus) and other four were Gram-negative (Stenotrophomonas, Vibrio, Raoultella and Enterobacter). Plasmids and merA genes were found and their sequences determined. Fluorescence in situ hybridization (FISH) technique shows the presence of Firmicutes, Actinobacteria and Gammaproteobacteria by using different molecular probes in siphon and gills. Bacterial clumps inside clam flesh were observed and even a Gram-negative endosymbiont was disclosed by transmission electronic microscope inside clam cells. Bacteria harbored in cavities of soft tissue have mercury detoxifying activity. This feature was confirmed by the determination of mercuric reductase in glass-homogenized siphons and gills. -- Highlights: ► We isolated Gram-positive and Gram-negative Hg resistant strains from soft tissues of Ruditapes philippinarum. ► We identify 14 mercury resistant strains by 16S rRNA gene sequences. ► Bacteria in siphon and gill tissues of clams were observed by TEM and identified

76 FR 46282 - Pacific Gas and Electric Company; Notice of Application for Amendment of License and Soliciting...

Science.gov (United States)

2011-08-02

... amendment of flows from FERC if the departure from flows lasts for more than two weeks. PG&E is planning to... the absence of a release from Dinkey Creek Siphon, the flow requirement below the Balch Afterbay Dam... of water around the construction area. It is estimated that the minimum flow requirement of 15 cubic...

Numerical model of simulation for solar collector of water heating; Modelo de simulaco numerica para colector solar de aquecimento de agua

Energy Technology Data Exchange (ETDEWEB)

Silva, A. C. G. C.; Dutra, J. C. C.; Henriquez, J. R.; Michalewicz, J. S.

2008-07-01

Before being installed a solar heater, It must be tested, numerical or experimentally to get his characteristic equation, which is the efficiency curve, plotted as a function on the temperature of entry and solar incident radiation on the collector. In this work was developed a tool for numerical simulation of heating water flat-plate solar collectors. This tool has been developed from a mathematical model which is composed of a system of equations. In the model are included equations of balance energy for the collector, equation of the first law, the law of cooling equation of Newton, convective heat transfer coefficient correlations, equations for calculating the solar incident radiation, and one equation that calculates of the water flow due to the siphon effect. The solution of the equations system was obtained by the multidimensional version of the Newton-Raphson method. the model was validated with experimental data from literature. The results shows, that it is a very interesting tool to simulate efficiency curve of the solar collector. (Author)

Precise determination of the Bragg peak position of proton beams in liquid water

International Nuclear Information System (INIS)

Marouane, Abdelhak; Ouaskit, Said; Inchaouh, Jamal

2011-01-01

The influence of water molecules on the surrounding biological molecules during irradiation with protons is currently a major subject in radiation science. Proton collisions with the water molecules are estimated around the Bragg peak region, taking into account ionization, excitation, charge-changing processes, and energetic secondary electron behavior. The Bragg peak profile and position was determined by adopting a new approach involving discretization, incrementation, and dividing the target into layers, the thickness of each layer being selected randomly from a distribution weighted by the values of the total interaction cross section, from excitation up to ionization of the target and the incident projectile charge exchange. The calculation was carried out by a Monte-Carlo simulation in the energy range 20 ≤ E ≤ 10 8 eV, including the relativistic corrections.

Spectral detection of near-surface moisture content and water-table position in northern peatland ecosystems

Science.gov (United States)

Karl M. Meingast; Michael J. Falkowski; Evan S. Kane; Lynette R. Potvin; Brian W. Benscoter; Alistair M.S. Smith; Laura L. Bourgeau-Chavez; Mary Ellen. Miller

2014-01-01

Wildland fire occurrence has been increasing in peatland ecosystems during recent decades. As such, there is a need for broadly applicable tools to detect and monitor controls on combustion such as surface peat moisture and water-table position. A field portable spectroradiometer was used to measure surface reflectance of two Sphagnum moss-dominated...

Assessment of drinking water quality using ICP-MS and microbiological methods in the Bholakpur area, Hyderabad, India.

Science.gov (United States)

Abdul, Rasheed M; Mutnuri, Lakshmi; Dattatreya, Patil J; Mohan, Dayal A

2012-03-01

A total of 16 people died and over 500 people were hospitalized due to diarrhoeal illness in the Bholakpur area of Hyderabad, India on 6th May 2009. A study was conducted with immediate effect to evaluate the quality of municipal tap water of the Bholakpur locality. The study consists of the determination of physico-chemical properties, trace metals, heavy metals, rare earth elements and microbiological quality of drinking water. The data showed the variation of the investigated parameters in samples as follows: pH 7.14 to 8.72, EC 455 to 769 μS/cm, TDS 303.51 to 515.23 ppm and DO 1.01 to 6.83 mg/L which are within WHO guidelines for drinking water quality. The water samples were analyzed for 27 elements (Li, Be, B, Na, Mg, Al, Si, K, Ca, V, Cr, Mn, Fe, Ni, Co, Cu, Zn, As, Se, Rb, Sr, Mo, Ag, Cd, Sb, Ba and Pb) using inductively coupled plasma-mass spectrometry (ICP-MS). The concentrations of Fe (0.12 to 1.13 mg/L), Pb (0.01 to 0.07 mg/L), Cu (0.01 to 0.19 mg/L), Ni (0.01 to 0.15 mg/L), Al (0.16 to 0.49 mg/L), and Na (38.36 to 68.69 mg/L) were obtained, which exceed the permissible limits of the World Health Organization (WHO) for drinking water quality guidelines. The remaining elements were within the permissible limits. The microbiological quality of water was tested using standard plate count, membrane filtration technique, thermotolerant coliform (TTC), and most probable number (MPN) methods. The total heterotrophic bacteria ranged from 1.0 × 10(5) to 18 × 10(7 )cfu/ml. Total viable bacteria in all the water samples were found to be too numerable to count and total number of coliform bacteria in all water samples were found to be of order of 1,100 to >2,400 MPN index/100 ml. TTC tested positive for coliform bacteria at 44.2°C. All the water samples of the study area exceeded the permissible counts of WHO and that (zero and minimal counts) of the control site (National Geophysical Research Institute) water samples. Excessively high colony numbers indicate

The Development of a Roof Integrated Solar Hot Water System

Energy Technology Data Exchange (ETDEWEB)

Menicucci, David F. [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States). Energy Infrastructure and DER Dept.; Moss, Timothy A. [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States). Solar Technologies Dept.; Palomino, G. Ernest [Salt River Project (SRP), Tempe, AZ (United States)

2006-09-01

The Salt River Project (SRP), in conjunction with Sandia National Laboratories (SNL) and Energy Laboratories, Inc. (ELI), collaborated to develop, test, and evaluate an advanced solar water-heating product for new homes. SRP and SNL collaborated under a Department of Energy Cooperative Research and Development Agreement (CRADA), with ELI as SRP's industry partner. The project has resulted in the design and development of the Roof Integrated Thermal Siphon (RITH) system, an innovative product that features complete roof integration, a storage tank in the back of the collector and below the roofline, easy installation by homebuilders, and a low installed cost. SRP's market research guided the design, and the laboratory tests conducted at SNL provided information used to refine the design of field test units and indicated that the RITH concept is viable. ELI provided design and construction expertise and is currently configured to manufacture the units. This final report for the project provides all of the pertinent and available materials connected to the project including market research studies, the design features and development of the system, and the testing and evaluation conducted at SNL and at a model home test site in Phoenix, Arizona.

Refurbishing the seals of the H2S compressors in the isotopic exchange installations at the Heavy Water Reprocessing Plant. Technical solutions for replacing liquid seals by dry seals

International Nuclear Information System (INIS)

Panait; Adrian; Serban, Viorel; Androne, Marian; Florea, Ioana; Ciocan, George; State, Elena

2004-01-01

pressure required by the dynamic stage is self-supplied by mounting inside a toroidal housing around the driving shaft a mini-rotor fastened to the shaft. The dynamic sub-stage is a micro-compressor or a micro-pump operating in a free-motion regime what supplies re-circulation of only a few percents of the maximal cooling capacity of the micro-installation. The working fluid for the dynamical sub-stage could be either the working gas (H 2 S, for the present case) or a neutral gas (nitrogen, for instance) or else a liquid (water or oil). The static sub-stage is made of elastic elements of siphon type, mounted co-axially with the driving shaft, which in case of a pressure difference between interior and exterior ensures self-sealing by the axial motion of a diaphragm fastened to an end of the siphon. On the opposite side of the diaphragm a gasket is provided which ensures the sealing on a disk fastened on the driving shaft. Two elastic enclosures between the two siphons form by means of which one can control when necessary the enclosure/opening of the sealing. Hence in the new system the oil for sealing is totally eliminated and the adjacent installations for pumping, cooling and cleaning as well. Instead the technological water is used which after ensuring the sealing is directed towards the isotopic exchange column. Hence, it ensures the pressure self-regulation on the dynamical stage thus avoiding automation systems which could lower the reliability of this new system of total sealing

Complex rheological properties of a water-soluble extract from the fronds of the black tree fern, Cyathea medullaris.

Science.gov (United States)

Goh, Kelvin K T; Matia-Merino, Lara; Hall, Christopher E; Moughan, Paul J; Singh, Harjinder

2007-11-01

A water-soluble extract was obtained from the fronds of a New Zealand native black tree fern (Cyathea medullaris or Mamaku in Māori). The extract exhibited complex rheological behavior. Newtonian, shear-thinning, shear-thickening, thixotropic, antithixotropic, and viscoelastic behaviors were observed depending on polymer concentration, shear rate, and shear history. The extract also displayed rod-climbing and self-siphoning properties typical of viscoelastic fluids. Such complex rheological properties have been reported in synthetic or chemically modified polymers but are less frequent in unmodified biopolymers. Although Mamaku extract obtained from the pith of the fern has been traditionally used by the Māori in New Zealand for treating wounds and diarrhea among other ailments, this material has never been characterized before. This study reports on the chemical composition of the extract and on its viscoelastic properties through rotational and oscillatory rheological measurements. Explanations of the mechanism behind the rheological properties were based on transient network models for associating polymers.

Evaluation of tumor invasion in gastric carcinoma with CT using water as an oral contrast agent in prone position

International Nuclear Information System (INIS)

Chung, Jin Il; Lee, Jong Tae; Yoo, Hyung Sik; Lee, Byung Hee; Bae, Jong Yup

1994-01-01

To evaluate the accuracy of CT using water as an oral contrast material in a prone position in determining the depth of tumor invasion in gastric cancer patients. Thirty three patients(19 male, 14 female) with surgically confirmed gastric cancer were studied. We performed CT in a prone position after ingestion of 1 liter of pure water. CT findings were classified into 4 groups by the morphologic appearance of infiltrates in the perigastric fat plane: normal perigastric fat(S0), fine mottled densities(S1), irregular aggregated or liner densities(S2) and direct extension and invasion of tumor into contiguous structures(S3). Also we prospectively compared the CT staging with pathologic T staging according to the TNM systems. The overall accuracy of CT staging in determining the pathologic T factor was 69.6%. As we regarded T1 and T2 lesions as one group on CT, the accuracy of CT staging was increased to 80.2% because of a limitation of CT for distinguishing T1 from T2 lesions. Prone position CT using water as an oral contrast agent is quite accurate in determining the T staging of gastric carcinoma

Emerging organic pollutants in the vadose zone of a soil aquifer treatment system: Pore water extraction using positive displacement.

Science.gov (United States)

Sopilniak, Alexander; Elkayam, Roy; Rossin, Anna Voloshenko; Lev, Ovadia

2018-01-01

Trace organic compounds in effluents, water streams and aquifers are amply reported. However, the mobile pool of Emerging Organic Contaminants (EOCs) in the deep parts of the vadose zone is hard to estimate, due to difficulties in extraction of sufficient quantity of pore water. Here, we present a new methodology for depth profiling of EOCs in pore water by Positive Displacement Extraction (PDE): Pore water extraction from unsaturated soil samples is carried out by withdrawal of soil cores by direct-push drilling and infiltrating the core by organics free water. We show that EOC concentrations in the water eluted in the plateau region of the inverse breakthrough curve is equal to their pore water concentrations. The method was previously validated for DOC extraction, and here the scope of the methodology is extended to pore water extraction for organic pollutants analysis. Method characteristics and validation were carried out with atrazine, simazine, carbamazepine, venlafaxine, O-desmethylvenlafaxine and caffeine in the concentration range of several ng to several μg/liter. Validation was carried out by laboratory experiments on three different soils (sandy, sandy-clayey and clayey). Field studies in the vadose zone of a SAT system provided 27 m deep EOC profiles with less than 1.5 m spatial resolution. During the percolation treatment, carbamazepine remained persistent, while the other studied EOCs were attenuated to the extent of 50-99%.The highest degradation rate of all studied EOCs was in the aerobic zone. EOC levels based on PDE and extraction by centrifugation were compared, showing a positive bias for centrifugation. Copyright © 2017 Elsevier Ltd. All rights reserved.

Factors Affecting Zebra Mussel Kill by the Bacterium Pseudomonas fluorescens

Energy Technology Data Exchange (ETDEWEB)

Daniel P. Molloy

2004-02-24

The specific purpose of this research project was to identify factors that affect zebra mussel kill by the bacterium Pseudomonas fluorescens. Test results obtained during this three-year project identified the following key variables as affecting mussel kill: treatment concentration, treatment duration, mussel siphoning activity, dissolved oxygen concentration, water temperature, and naturally suspended particle load. Using this latter information, the project culminated in a series of pipe tests which achieved high mussel kill inside power plants under once-through conditions using service water in artificial pipes.

Changes in seed oil and protein contents of maize cultivars at different positions on the ear in response to water limitation

Directory of Open Access Journals (Sweden)

Kazem Ghassemi-Golezani

2016-10-01

Full Text Available A field experiment was carried out as split-split plot in 2014 to assess the effects of four irrigation treatments (irrigations after 60, 80, 100 and 120 mm evaporation, respectively on oil and protein changes of maize cultivars (SC704, NS640 and DC303: Late, mid and early maturing cultivars, respectively at different seed positions on the ear (upper, middle and lower positions on the ear. Overall, the highest seed yield was obtained from SC704, followed by NS640 and DC303 cultivars. Seed yield of all cultivars was higher at lower seed position on ear than at middle and upper parts of the ear under different irrigation treatments. The highest oil and protein yields were also recorded for seeds at lower position on the ear. Seed yield of all maize cultivars at various seed positions decreased with increasing irrigation intervals. Oil percentage decreased, but protein percentage increased with decreasing water availability. Water limitation decreased oil and protein yields of maize cultivars. Changes in protein and oil yields of maize cultivars at different seed positions and irrigation treatments were attributed to changes in seed yield.

Model-assisted measurements of suspension-feeding flow velocities.

Science.gov (United States)

Du Clos, Kevin T; Jones, Ian T; Carrier, Tyler J; Brady, Damian C; Jumars, Peter A

2017-06-01

Benthic marine suspension feeders provide an important link between benthic and pelagic ecosystems. The strength of this link is determined by suspension-feeding rates. Many studies have measured suspension-feeding rates using indirect clearance-rate methods, which are based on the depletion of suspended particles. Direct methods that measure the flow of water itself are less common, but they can be more broadly applied because, unlike indirect methods, direct methods are not affected by properties of the cleared particles. We present pumping rates for three species of suspension feeders, the clams Mya arenaria and Mercenaria mercenaria and the tunicate Ciona intestinalis , measured using a direct method based on particle image velocimetry (PIV). Past uses of PIV in suspension-feeding studies have been limited by strong laser reflections that interfere with velocity measurements proximate to the siphon. We used a new approach based on fitting PIV-based velocity profile measurements to theoretical profiles from computational fluid dynamic (CFD) models, which allowed us to calculate inhalant siphon Reynolds numbers ( Re ). We used these inhalant Re and measurements of siphon diameters to calculate exhalant Re , pumping rates, and mean inlet and outlet velocities. For the three species studied, inhalant Re ranged from 8 to 520, and exhalant Re ranged from 15 to 1073. Volumetric pumping rates ranged from 1.7 to 7.4 l h -1 for M . arenaria , 0.3 to 3.6 l h -1 for M . m ercenaria and 0.07 to 0.97 l h -1 for C . intestinalis We also used CFD models based on measured pumping rates to calculate capture regions, which reveal the spatial extent of pumped water. Combining PIV data with CFD models may be a valuable approach for future suspension-feeding studies. © 2017. Published by The Company of Biologists Ltd.

The influence of drought on the water uptake by Scots pines (Pinus sylvestris L. at different positions in the tree stand

Directory of Open Access Journals (Sweden)

Boczoń Andrzej

2015-12-01

Full Text Available Periodically occurring drought is typical for the climate of Poland. In habitats supplied exclusively with rain water, tree stands are frequently exposed to the negative effects of water deficit in the soil. The aim of this study was to examine the water uptake and consumption of two individual Scots pine trees under drought conditions. The trees were located at different positions within the stand and at the time of study were over 150 years old. Soil moisture, availability of soil water and the quantity of water uptake by the individual trees were examined by measuring the water velocity inside the trunks (Thermal Dissipation Probe method.

What Point-of-Use Water Treatment Products Do Consumers Use? Evidence from a Randomized Controlled Trial among the Urban Poor in Bangladesh

Science.gov (United States)

Luoto, Jill; Najnin, Nusrat; Mahmud, Minhaj; Albert, Jeff; Islam, M. Sirajul; Luby, Stephen; Unicomb, Leanne; Levine, David I.

2011-01-01

Background There is evidence that household point-of-use (POU) water treatment products can reduce the enormous burden of water-borne illness. Nevertheless, adoption among the global poor is very low, and little evidence exists on why. Methods We gave 600 households in poor communities in Dhaka, Bangladesh randomly-ordered two-month free trials of four water treatment products: dilute liquid chlorine (sodium hypochlorite solution, marketed locally as Water Guard), sodium dichloroisocyanurate tablets (branded as Aquatabs), a combined flocculant-disinfectant powdered mixture (the PUR Purifier of Water), and a silver-coated ceramic siphon filter. Consumers also received education on the dangers of untreated drinking water. We measured which products consumers used with self-reports, observation (for the filter), and chlorine tests (for the other products). We also measured drinking water's contamination with E. coli (compared to 200 control households). Findings Households reported highest usage of the filter, although no product had even 30% usage. E. coli concentrations in stored drinking water were generally lowest when households had Water Guard. Households that self-reported product usage had large reductions in E. coli concentrations with any product as compared to controls. Conclusion Traditional arguments for the low adoption of POU products focus on affordability, consumers' lack of information about germs and the dangers of unsafe water, and specific products not meshing with a household's preferences. In this study we provided free trials, repeated informational messages explaining the dangers of untreated water, and a variety of product designs. The low usage of all products despite such efforts makes clear that important barriers exist beyond cost, information, and variation among these four product designs. Without a better understanding of the choices and aspirations of the target end-users, household-based water treatment is unlikely to reduce

Thruster allocation for dynamical positioning

NARCIS (Netherlands)

Poppe, K.; van den Berg, J.B.; Blank, E.; Archer, C.; Redeker, M.; Kutter, M.; Hemker, P.

2010-01-01

Positioning a vessel at a fixed position in deep water is of great importance when working offshore. In recent years a Dynamical Positioning (DP) system was developed at Marin [2]. After the measurement of the current position and external forces (like waves, wind etc.), each thruster of the vessel

Capture and characterization of particulate phosphorus from farm drainage waters in the Everglades Agricultural Area

Science.gov (United States)

Bhadha, J. H.; Lang, T.; Daroub, S.

2012-12-01

The buildup of highly labile, organic, phosphorus (P)-enriched sediments in farms canals within the Everglades Agricultural Area (EAA) has been associated with the production of floating aquatic vegetation. During drainage events, these sediments are susceptible to transport and contribute to the overall P load. In order to evaluate the total P load exiting the farm canals, a settling tank experiment was conducted to capture the sediments during drainage events from eight farms. Drainage water was channelized through two 200L polypropylene collection tanks which allowed sediments to settle at the bottom based on its particle size. Water was carefully siphoned out of the tanks and the sediments collected for analyses. A five step P-fractionation process was used to distinguish organic (o) and inorganic (i) forms of P: KCl extractable P, NaOH extractable P, HCl extractable P, and residual P. The KCl-Pi fraction represents the labile Pi that is water soluble and exchangeable (loosely adsorbed); NaOH extractable P represents Fe- and Al- bound inorganic P (NaOH-Pi) and organic P associated with humic and fulvic acids (NaOH-Po). The HCl-Pi fraction includes Ca- and Mg- bound P, while Residue-P represents recalcitrant organic P compounds and P bound to minerals. The sediments were also used to conduct a P-flux study under both aerobic and anaerobic conditions. Our goal is to provide growers with vital information and insight into P loading that will help them in their efforts to reduce off-farm P loads in the EAA.

[A new cause of ocular trauma due to "blast" injury].

Science.gov (United States)

Chiriac, I

1997-01-01

Are presented five observations of ocular trauma caused by blast of plastic siphon-bottles during their loading. Two of them result in eyeball evisceration, in the three others the visual function was kept. We deem necessary the respecting of single use instruction for these plastic containers and possibly--the ban of theirs using like siphon.

Analysis of elemental concentration using ICP-AES and pathogen indicator in drinking water of Qasim Abad, District Rawalpindi, Pakistan.

Science.gov (United States)

Sehar, Shama; Naz, Iffat; Ali, Naeem; Ahmed, Safia

2013-02-01

The present study was conducted to investigate drinking water quality (groundwater) from water samples taken from Qasim Abad, a locality of approximately 5,000 population, situated between twin cities Rawalpindi and Islamabad in Pakistan. The main sources of drinking water in this area are water bores which are dug upto the depth of 250-280 ft in almost every house. The study consists of the determination of physico-chemical properties, trace metals, heavy metals, rare earth elements and microbiological quality of drinking water. The data showed the variation of the investigated parameters in samples as follows: pH 6.75 to 8.70, electrical conductivity 540 to 855 μS/cm, total dissolved solids 325.46 to 515.23 ppm and dissolved oxygen 1.50 to 5.64 mg/L which are within the WHO guidelines for drinking water quality. The water samples were analysed for 30 elements (aluminium, iron, magnesium, manganese, silicon, zinc, molybdenum, titanium, chromium, nickel, tungsten, silver, arsenic, boron, barium, beryllium, cadmium, cobalt, copper, gallium, mercury, lanthanum, niobium, neodymium, lead, selenium, samarium, tin, vanadium and zirconium) by using inductively coupled plasma atomic emission spectroscopy. The organic contamination was detected in terms of most probable number (MPN) of faecal coliforms. Overall, elemental levels were lower than the recommended values but three water bores (B-1, B-6, B-7) had higher values of iron (1.6, 2.206, 0.65 ppm), two water bores (B-1, B-6) had higher values of aluminium (0.95, 1.92 ppm), respectively, and molybdenum was higher by 0.01 ppm only in one water bore (B-11). The total number of coliforms present in water samples was found to be within the prescribed limit of the WHO except for 5 out of 11 bore water samples (B-2, B-3, B-4, B-8, B-11), which were found in the range 5-35 MPN/100 mL, a consequence of infiltration of contaminated water (sewage) through cross connection, leakage points and back siphoning.

DWAF water services IAM strategy positioned within the context of other major national IAM initiatives

CSIR Research Space (South Africa)

Wall, K

2008-05-01

Full Text Available STRATEGY POSITIONED WITHIN THE CONTEXT OF OTHER MAJOR NATIONAL IAM INITIATIVES Nino Manus, Kribbs Moodley, Kevin Wall, Louis Boshoff and Arno Ottermann Department of Water Affairs and Forestry, Private Bag X313, Pretoria 0001. ManusA@dwaf.gov.za P D... into one or other of 9 “solution types”, viz: • Awareness • Finance • Guidelines • HR (i.e. including ski l ls and appointments) • Legal and procurement • Monitoring and evaluation • Management and leadership • Operation and maintenance...

Desalination by very low temperature nuclear heat

International Nuclear Information System (INIS)

Saari, Risto

1977-01-01

A new sea water desalination method has been developed: Nord-Aqua Vacuum Evaporation, which utilizes waste heat at a very low temperature. The requisite vacuum is obtained by the aid of a barometric column and siphon, and the dissolved air is removed from the vacuum by means of water flows. According to test results from a pilot plant, the process is operable if the waste heat exists at a temperature 7degC higher than ambient. The pumping energy which is then required is 9 kcal/kg, or 1.5% of the heat of vaporization of water. Calculations reveal that the method is economically considerably superior to conventional distilling methods. (author)

Position of the academy of nutrition and dietetics: nutrition security in developing nations: sustainable food, water, and health.

Science.gov (United States)

Nordin, Stacia M; Boyle, Marie; Kemmer, Teresa M

2013-04-01

It is the position of the Academy of Nutrition and Dietetics that all people should have consistent access to an appropriately nutritious diet of food and water, coupled with a sanitary environment, adequate health services, and care that ensure a healthy and active life for all household members. The Academy supports policies, systems, programs, and practices that work with developing nations to achieve nutrition security and self-sufficiency while being environmentally and economically sustainable. For nations to achieve nutrition security, all people must have access to a variety of nutritious foods and potable drinking water; knowledge, resources, and skills for healthy living; prevention, treatment, and care for diseases affecting nutrition status; and safety-net systems during crisis situations, such as natural disasters or deleterious social and political systems. More than 2 billion people are micronutrient deficient; 1.5 billion people are overweight or obese; 870 million people have inadequate food energy intake; and 783 million people lack potable drinking water. Adequate nutrient intake is a concern, independent of weight status. Although this article focuses on nutritional deficiencies in developing nations, global solutions for excesses and deficiencies need to be addressed. In an effort to achieve nutrition security, lifestyles, policies, and systems (eg, food, water, health, energy, education/knowledge, and economic) contributing to sustainable resource use, environmental management, health promotion, economic stability, and positive social environments are required. Food and nutrition practitioners can get involved in promoting and implementing effective and sustainable policies, systems, programs, and practices that support individual, community, and national efforts. Copyright © 2013 Academy of Nutrition and Dietetics. Published by Elsevier Inc. All rights reserved.

Effects of water table position and plant functional group on plant community, aboveground production, and peat properties in a peatland mesocosm experiment (PEATcosm)

Science.gov (United States)

Lynette R. Potvin; Evan S. Kane; Rodney A. Chimner; Randall K. Kolka; Erik A. Lilleskov

2015-01-01

Aims Our objective was to assess the impacts of water table position and plant functional type on peat structure, plant community composition and aboveground plant production. Methods We initiated a full factorial experiment with 2 water table (WT) treatments (high and low) and 3 plant functional groups (PFG: sedge, Ericaceae,...

Effects of Position of Rainfed Rice Field in a Toposequence on Water Availability and Rice Yield in Central Java, Indonesia

OpenAIRE

SUGANDA, HUSEIN; PANINGBATAN, E.P; GUERRA, L.C; TUONG, T.P

2003-01-01

The productivity of rainfed rice needs to be increased in order to support the Indonesian Food Security programs, especially rice. Rainfall is one of the main sources of the water availability on the rainfed rice field. This research was conducted from October 2000 to February 2001 at four sites in Central Java Province. The objectives of this research were to study thevariability of water availability that influenced by toposequen's position and to analyze the rice yields due to treatments o...

Methane Occurrence in a Drinking Water Aquifer Before and During Natural Gas Production from the Marcellus Shale

Science.gov (United States)

Saiers, J. E.; Barth-Naftilan, E.

2017-12-01

More than 4,000 thousand wells have punctured aquifers of Pennsylvania's northern tier to siphon natural gas from the underlying Marcellus Shale. As drilling and hydraulic fracturing ramped up a decade ago, homeowner reports of well water contamination by methane and other contaminants began to emerge. Although made infrequently compared to the number of gas wells drilled, these reports were troubling and motivated our two-year, prospective study of groundwater quality within the Marcellus Shale Play. We installed multi-level sampling wells within a bedrock aquifer of a 25 km2 area that was targeted for shale gas development. These wells were sampled on a monthly basis before, during, and after seven shale gas wells were drilled, hydraulically fractured, and placed into production. The groundwater samples, together with surface water samples collected from nearby streams, were analyzed for hydrocarbons, trace metals, major ions, and the isotopic compositions of methane, ethane, water, strontium, and dissolved inorganic carbon. With regard to methane in particular, concentrations ranged from under 0.1 to over 60 mg/L, generally increased with aquifer depth, and, at some sites, exhibited considerable temporal variability. The isotopic composition of methane and hydrocarbon ratios also spanned a large range, suggesting that methane origins are diverse and, notably, shift on the time scale of this study. We will present inferences on factors governing methane occurrence across our study area by interpreting time-series data on methane concentrations and isotopic composition in context of local hydrologic variation, companion measurements of groundwater chemistry, and the known timing of key stages of natural gas extraction.

Influence of water vapour on the height distribution of positive ions, effective recombination coefficient and ionisation balance in the quiet lower ionosphere

Directory of Open Access Journals (Sweden)

V. Barabash

2014-03-01

Full Text Available Mesospheric water vapour concentration effects on the ion composition and electron density in the lower ionosphere under quiet geophysical conditions were examined. Water vapour is an important compound in the mesosphere and the lower thermosphere that affects ion composition due to hydrogen radical production and consequently modifies the electron number density. Recent lower-ionosphere investigations have primarily concentrated on the geomagnetic disturbance periods. Meanwhile, studies on the electron density under quiet conditions are quite rare. The goal of this study is to contribute to a better understanding of the ionospheric parameter responses to water vapour variability in the quiet lower ionosphere. By applying a numerical D region ion chemistry model, we evaluated efficiencies for the channels forming hydrated cluster ions from the NO+ and O2+ primary ions (i.e. NO+.H2O and O2+.H2O, respectively, and the channel forming H+(H2On proton hydrates from water clusters at different altitudes using profiles with low and high water vapour concentrations. Profiles for positive ions, effective recombination coefficients and electrons were modelled for three particular cases using electron density measurements obtained during rocket campaigns. It was found that the water vapour concentration variations in the mesosphere affect the position of both the Cl2+ proton hydrate layer upper border, comprising the NO+(H2On and O2+(H2On hydrated cluster ions, and the Cl1+ hydrate cluster layer lower border, comprising the H+(H2On pure proton hydrates, as well as the numerical cluster densities. The water variations caused large changes in the effective recombination coefficient and electron density between altitudes of 75 and 87 km. However, the effective recombination coefficient, αeff, and electron number density did not respond even to large water vapour concentration variations occurring at other altitudes in the mesosphere. We determined the water

33 CFR 161.20 - Position Report (PR).

Science.gov (United States)

2010-07-01

... 33 Navigation and Navigable Waters 2 2010-07-01 2010-07-01 false Position Report (PR). 161.20 Section 161.20 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED... Report (PR). A vessel must report its name and position: (a) Upon point of entry into a VMRS area; (b) At...

Suction forces generated by passive bile bag drainage on a model of post-subdural hematoma evacuation.

Science.gov (United States)

Tenny, Steven O; Thorell, William E

2018-05-05

Passive drainage systems are commonly used after subdural hematoma evacuation but there is a dearth of published data regarding the suction forces created. We set out to quantify the suction forces generated by a passive drainage system. We created a model of passive drainage after subdural hematoma evacuation. We measured the maximum suction force generated with a bile bag drain for both empty drain tubing and fluid-filled drain tube causing a siphoning effect. We took measurements at varying heights of the bile bag to analyze if bile bag height changed suction forces generated. An empty bile bag with no fluid in the drainage tube connected to a rigid, fluid-filled model creates minimal suction force of 0.9 mmHg (95% CI 0.64-1.16 mmHg). When fluid fills the drain tubing, a siphoning effect is created and can generate suction forces ranging from 18.7 to 30.6 mmHg depending on the relative position of the bile bag and filled amount of the bile bag. The suction forces generated are statistically different if the bile bag is 50 cm below, level with or 50 cm above the experimental model. Passive bile bag drainage does not generate significant suction on a fluid-filled rigid model if the drain tubing is empty. If fluid fills the drain tubing then siphoning occurs and can increase the suction force of a passive bile bag drainage system to levels comparable to partially filled Jackson-Pratt bulb drainage.

Monitoring the impact of urban effluents on mineral contents of water and sediments of four sites of the river Ravi, Lahore.

Science.gov (United States)

Shakir, Hafiz Abdullah; Qazi, Javed Iqbal; Chaudhry, Abdul Shakoor

2013-12-01

We assessed the impact of urban effluents on the concentrations of selected minerals (Cd, Cr, Cu, Fe, Pb, Zn, Mn, Ni, and Hg) in river Ravi before and after its passage through Lahore city. Water and sediment samples were collected from three lowly to highly polluted downstream sites (Shahdera (B), Sunder (C), and Balloki (D)) alongside the least polluted upstream site (Siphon (A)) during high and low river flow seasons. All the mineral concentrations increased up to site C but stabilized at site D, showing some recovery as compared to the third sampling site. The trend of mean mineral concentration was significantly higher during the low than the high flow season at all the sites. The mean Hg concentrations approached 0.14 and 0.12 mg/l at site A which increased (%) up to 107 and 25% at site B, 1,700 and 1,317% at site C, and 1,185 and 1,177% at site D during low and high river flows, respectively. All mineral concentrations were much higher in the sediment than the water samples. Mean Cd (917%), Cr (461%), Cu (300%), Fe (254%), Pb (179%), Zn (170%), Mn (723%), Ni (853%), and Hg (1,699%) concentrations were higher in riverbed sediments sampled from site C in comparison with the sample collected at site A during low flow season. The domestic and industrial discharges from Lahore city have created undesirable water qualities during the low river flow season. As majority of the mineral levels in the river Ravi were higher than the permissible and safe levels, this is of immediate concern for riverine fish consumers and the users of water for recreation and even irrigation. The use of these waters may pose health risks, and therefore, urgent intervention strategies are needed to minimize river water pollution and its impact on fish-consuming communities of this study area and beyond.

Impact of continuous positive airway pressure on the pulmonary changes promoted by immersion in water

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Danize Aparecida Rizzetti

Full Text Available ABSTRACT Objective: To determine whether different levels of CPAP improve the lung volumes and capacities of healthy subjects immersed in water. Methods: This was a randomized clinical trial, conducted between April and June of 2016, involving healthy female volunteers who were using oral contraceptives. Three 20-min immersion protocols were applied: control (no CPAP; CPAP5 (CPAP at 5 cmH2O; and CPAP10 (CPAP at 10 cmH2O. We evaluated HR, SpO2, FVC, FEV1, the FEV1/FVC ratio, peak expiratory flow rate (PEFR, and FEF25-75% at three time points: pre-immersion; 10 min after immersion; and 10 min after the end of each protocol. Results: We evaluated 13 healthy volunteers. The CPAP10 protocol reversed the restrictive pattern of lung function induced by immersion in water, maintaining pulmonary volumes and capacities for a longer period than did the CPAP5 protocol. Conclusions: When the hemodynamic change causing a persistent lung disorder, only the application of higher positive pressures is effective in maintaining long-term improvements in the pulmonary profile.

Impact of continuous positive airway pressure on the pulmonary changes promoted by immersion in water.

Science.gov (United States)

Rizzetti, Danize Aparecida; Quadros, Janayna Rodembuch Borba; Ribeiro, Bruna Esmerio; Callegaro, Letícia; Veppo, Aline Arebalo; Wiggers, Giulia Alessandra; Peçanha, Franck Maciel

2017-01-01

To determine whether different levels of CPAP improve the lung volumes and capacities of healthy subjects immersed in water. This was a randomized clinical trial, conducted between April and June of 2016, involving healthy female volunteers who were using oral contraceptives. Three 20-min immersion protocols were applied: control (no CPAP); CPAP5 (CPAP at 5 cmH2O); and CPAP10 (CPAP at 10 cmH2O). We evaluated HR, SpO2, FVC, FEV1, the FEV1/FVC ratio, peak expiratory flow rate (PEFR), and FEF25-75%) at three time points: pre-immersion; 10 min after immersion; and 10 min after the end of each protocol. We evaluated 13 healthy volunteers. The CPAP10 protocol reversed the restrictive pattern of lung function induced by immersion in water, maintaining pulmonary volumes and capacities for a longer period than did the CPAP5 protocol. When the hemodynamic change causing a persistent lung disorder, only the application of higher positive pressures is effective in maintaining long-term improvements in the pulmonary profile.

The influence of game duration and playing position on intensity of exercise during match-play in elite water polo players.

Science.gov (United States)

Platanou, T; Geladas, N

2006-11-01

In this study, we assessed exercise intensity in 20 water polo games of different duration. The hypothesis that right wing players perform at a higher intensity than back and forward central players was also tested. Thirty water polo players, equally split between three field positions, participated in the study. Initially, their performance-related physiological capabilities were evaluated. Subsequently, during water polo games of short (4 x 7-min periods) or long duration (4 x 9-min periods), heart rate was monitored continuously and blood lactate concentration was measured at the end of each period. Activity patterns were also recorded using a video camera. Mean heart rate over the entire game was 156 +/- 18 beats x min(-1). Overall exercise intensity fluctuated around a value corresponding to the lactate threshold (4.03 +/- 0.96 mmol x l(-1), 86 +/- 5% of peak heart rate) and decreased (P game time (4.22 +/- 1.8 and 3.47 +/- 1.9 mmol x l(-1) in the second and fourth quarter, respectively). During the last 6 min, heart rate was higher (P games of short duration (156 +/- 3 beats x min(-1)) than in games of long duration (152 +/- 8 beats x min(-1)). Video analysis showed that the percentage of time spent in low-intensity activities (i.e. "out of game") was lower (23 vs. 26%), whereas that in high-intensity activities (i.e. "sprinting crawl") was higher (21 vs. 19%), in games of short compared with long duration. No difference was observed among players of various field positions in any of the variables examined. Thus during match-play, games of long duration produced significantly lower heart rate responses than games of short duration, and the physiological response exhibited by the players was not affected by field position. The water polo authorities should consider these results before changing game duration and coaches should prepare their athletes accordingly.

Further development of the spindle seal on reactor valves and development for increasing serviceability

International Nuclear Information System (INIS)

Zilling, H.

1977-01-01

A literature search concerning packing glands for sealing oscillating rods was marginally profitable. In order to design single-wall siphons a programme has been developed, in which by applying boundary conditions such as range, pressure, setting - the distortion tension which occur in each section of the siphon and also its life can be calculated. In the 'serviceability' project records have been kept during the installation of dampers and valves. (orig.) [de

Gastrointestinal tract wall visualization and distention during abdominal and pelvic multidetector CT with a neutral barium sulphate suspension: comparison with positive barium sulphate suspension and with water.

Science.gov (United States)

Oliva, M R; Erturk, S M; Ichikawa, T; Rocha, T; Ros, P R; Silverman, S G; Mortele, K J

2012-01-01

When examining patients with contrast-enhanced multidetector-row CT, we determined if the stomach and small bowel were visualized and distended better with a neutral barium sulphate suspension than with positive barium sulphate suspension or water. After obtaining approval from our institutional review board, 156 patients (women: 84; mean age: 54 yrs) with no history of gastrointestinal tract disease were randomized prospectively to receive orally either 900 ml of neutral (0.1% w/v) barium sulphate suspension (n = 53), 900 ml of positive (2.1% w/v) barium sulphate suspension (n = 53), or 900 ml of water (n = 50), prior to undergoing contrast-enhanced abdominal and pelvic multidetector-row CT. Two independent radiologists evaluated the stomach, and small bowel, for luminal distension and wall visualization, using a five point scale. Results were compared using Kruskal-Wallis and Mann-Whitney U tests. The walls of the stomach, and small bowel were visualized better in patients who were administered neutral barium sulphate suspension than those who were administered either positive barium sulphate suspension (p barium sulphate suspension, the stomach and small bowel were distended better compared to patients administered water (p barium sulphate suspension (p contrast-enhanced abdominal and pelvic multidetector-row CT, orally administered neutral barium sulphate suspension allows the gastrointestinal tract to be visualized and distended better than either positive barium sulphate suspension, or water.

Water hammer

International Nuclear Information System (INIS)

Anon.

1979-01-01

The overall NRC program for the resolution of the water hammer issue is divided into four tasks: water hammer summary reports; revision of CP and OL review procedures; water hammer positions for operating reactors; and water hammer safety studies

Detection device for the failed position in fuels

International Nuclear Information System (INIS)

Tokunaga, Kensuke; Nomura, Teiji; Hiruta, Koji

1985-01-01

Purpose: To detect the failed position of a fuel assembly with ease and safety. Constitution: A fuel assembly is tightly closed in a sipper tube equipped with a gas supply tube and a gas exhaust tube at the upper portion and a purified water injection tube and a draining tube at the lower end. Then, water in the sipper tube is drained to the lower portion of the fuel assembly by the pressure of gases while opening the gas supply tube and the draining tube, and closing the exhaust tube and the injection tube. Then, after closing the gas supply tube and the draining tube while opening theexhaust tube and the injection tube, purified water is injected into the sipper tube from the injection tube to an optional height till the fuel assembly is immersed. Then, after leaving for a predetermined of time, water is sampled and the radioactive material density therein is measured. By changing the injection level of the purified water, since the radioactive material density changes at the failed position, the failed position can be detected with ease. (Sekiya, K.)

Effect of Atmospheric Ions on Interfacial Water

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Chien-Chang Kurt Kung

2014-11-01

Full Text Available The effect of atmospheric positivity on the electrical properties of interfacial water was explored. Interfacial, or exclusion zone (EZ water was created in the standard way, next to a sheet of Nafion placed horizontally at the bottom of a water-filled chamber. Positive atmospheric ions were created from a high voltage source placed above the chamber. Electrical potential distribution in the interfacial water was measured using microelectrodes. We found that beyond a threshold, the positive ions diminished the magnitude of the negative electrical potential in the interfacial water, sometimes even turning it to positive. Additionally, positive ions produced by an air conditioner were observed to generate similar effects; i.e., the electrical potential shifted in the positive direction but returned to negative when the air conditioner stopped blowing. Sometimes, the effect of the positive ions from the air conditioner was strong enough to destroy the structure of interfacial water by turning the potential decidedly positive. Thus, positive air ions can compromise interfacial water negativity and may explain the known negative impact of positive ions on health.

Water calibration measurements for neutron radiography: Application to water content quantification in porous media

Energy Technology Data Exchange (ETDEWEB)

Kang, M., E-mail: kangm@ornl.gov [Department of Earth and Planetary Sciences, University of Tennessee, Knoxville, TN (United States); Chemical and Engineering Materials Division, Oak Ridge National Laboratory, Oak Ridge, TN (United States); Bilheux, H.Z., E-mail: bilheuxhn@ornl.gov [Chemical and Engineering Materials Division, Oak Ridge National Laboratory, Oak Ridge, TN (United States); Voisin, S. [Computational Sciences and Engineering Division, Oak Ridge National Laboratory, Oak Ridge, TN (United States); Cheng, C.L.; Perfect, E. [Department of Earth and Planetary Sciences, University of Tennessee, Knoxville, TN (United States); Horita, J. [Department of Geosciences, Texas Tech University, Lubbock, TX (United States); Warren, J.M. [Environmental Sciences Division, Oak Ridge National Laboratory, Oak Ridge, TN (United States)

2013-04-21

Using neutron radiography, the measurement of water thickness was performed using aluminum (Al) water calibration cells at the High Flux Isotope Reactor (HFIR) Cold-Guide (CG) 1D neutron imaging facility at Oak Ridge National Laboratory, Oak Ridge, TN, USA. Calibration of water thickness is an important step to accurately measure water contents in samples of interest. Neutron attenuation by water does not vary linearly with thickness mainly due to beam hardening and scattering effects. Transmission measurements for known water thicknesses in water calibration cells allow proper correction of the underestimation of water content due to these effects. As anticipated, strong scattering effects were observed for water thicknesses greater than 0.2 cm when the water calibration cells were positioned close to the face of the detector/scintillator (0 and 2.4 cm away, respectively). The water calibration cells were also positioned 24 cm away from the detector face. These measurements resulted in less scattering and this position (designated as the sample position) was used for the subsequent experimental determination of the neutron attenuation coefficient for water. Neutron radiographic images of moist Flint sand in rectangular and cylindrical containers acquired at the sample position were used to demonstrate the applicability of the water calibration. Cumulative changes in the water volumes within the sand columns during monotonic drainage determined by neutron radiography were compared with those recorded by direct reading from a burette connected to a hanging water column. In general, the neutron radiography data showed very good agreement with those obtained volumetrically using the hanging water-column method. These results allow extension of the calibration equation to the quantification of unknown water contents within other samples of porous media.

Positive impacts in soil and water conservation in an Andean region of South America: Case scenarios from a USAID multidisciplinary cooperative project

Science.gov (United States)

The USAID-SANREM-Virginia Polytechnic Institute project has made and continues to make an excellent impact, specifically showcasing the positive results of soil and water conservation (Barrera et al. 2010a; 2010b). This project has strong international cooperation between the USA, Ecuador and Bolivi...

14 CFR 23.523 - Design weights and center of gravity positions.

Science.gov (United States)

2010-01-01

... 14 Aeronautics and Space 1 2010-01-01 2010-01-01 false Design weights and center of gravity... Structure Water Loads § 23.523 Design weights and center of gravity positions. (a) Design weights. The water... water taxi and takeoff run) must be used. (b) Center of gravity positions. The critical centers of...

Diversity and antibiograms of bacterial organisms isolated from samples of household drinking-water consumed by HIV-positive individuals in rural settings, South Africa.

Science.gov (United States)

Samie, A; Mashao, M B; Bessong, P O; NKgau, T F; Momba, M N B; Obi, C L

2012-09-01

Diarrhoea is a hallmark of HIV infections in developing countries, and many diarrhoea-causing agents are often transmitted through water. The objective of the study was to determine the diversity and antibiotic susceptibility profiles of bacterial organisms isolated from samples of household drinking-water consumed by HIV-infected and AIDS patients. In the present study, household water stored for use by HIV-positive patients was tested for microbial quality, and isolated bacterial organisms were analyzed for their susceptibility profiles against 25 different antibiotics. The microbial quality of water was generally poor, and about 58% of water samples (n=270) were contaminated with faecal coliforms, with counts varying from 2 colony-forming unit (CFU)/100 mL to 2.4x10⁴ CFU/100 mL. Values of total coliform counts ranged from 17 CFU/100 mL to 7.9x10⁵/100 mL. In total, 37 different bacterial species were isolated, and the major isolates included Acinetobacter lwoffii (7.5%), Enterobacter cloacae (7.5%), Shigella spp. (14.2%), Yersinia enterocolitica (6.7%), and Pseudomonas spp. (16.3%). No Vibrio cholerae could be isolated; however, V. fluvialis was isolated from three water samples. The isolated organisms were highly resistant to cefazolin (83.5%), cefoxitin (69.2%), ampicillin (66.4%), and cefuroxime (66.2%). Intermediate resistance was observed against gentamicin (10.6%), cefepime (13.4%), ceftriaxone (27.6%), and cefotaxime (29.9%). Levofloxacin (0.7%), ceftazidime (2.2%), meropenem (3%), and ciprofloxacin (3.7%) were the most active antibiotics against all the microorganisms, with all recording less than 5% resistance. Multiple drug resistance was very common, and 78% of the organisms were resistant to three or more antibiotics. Education on treatment of household water is advised for HIV-positive patients, and measures should be taken to improve point-of-use water treatment as immunosuppressed individuals would be more susceptible to opportunistic

Rhizosphere hydrophobicity: A positive trait in the competition for water.

Science.gov (United States)

Zeppenfeld, Thorsten; Balkenhol, Niko; Kóvacs, Kristóf; Carminati, Andrea

2017-01-01

The ability to acquire water from the soil is a major driver in interspecific plant competition and it depends on several root functional traits. One of these traits is the excretion of gel-like compounds (mucilage) that modify physical soil properties. Mucilage secreted by roots becomes hydrophobic upon drying, impedes the rewetting of the soil close to the root, the so called rhizosphere, and reduces water availability to plants. The function of rhizosphere hydrophobicity is not easily understandable when looking at a single plant, but it may constitute a competitive advantage at the ecosystem level. We hypothesize that by making the top soil hydrophobic, deep-rooted plants avoid competititon with shallow-rooted plants. To test this hypothesis we used an individual-based model to simulate water uptake and growth of two virtual plant species, one deep-rooted plant capable of making the soil hydrophobic and a shallow-rooted plant. We ran scenarios with different precipitation regimes ranging from dry to wet (350, 700, and 1400 mm total annual precipitation) and from high to low precipitation frequencies (1, 7, and 14 days). Plant species abundance and biomass were chosen as indicators for competitiveness of plant species. At constant precipitation frequency mucilage hydrophobicity lead to a benefit in biomass and abundance of the tap-rooted population. Under wet conditions this effect diminished and tap-rooted plants were less productive. Without this trait both species coexisted. The effect of root exudation trait remained constant under different precipitation frequencies. This study shows that mucilage secretion is a competitive trait for the acquisition of water. This advantage is achieved by the modification of the soil hydraulic properties and specifically by inducing water repellency in soil regions which are shared with other species.

Rhizosphere hydrophobicity: A positive trait in the competition for water.

Directory of Open Access Journals (Sweden)

Thorsten Zeppenfeld

Full Text Available The ability to acquire water from the soil is a major driver in interspecific plant competition and it depends on several root functional traits. One of these traits is the excretion of gel-like compounds (mucilage that modify physical soil properties. Mucilage secreted by roots becomes hydrophobic upon drying, impedes the rewetting of the soil close to the root, the so called rhizosphere, and reduces water availability to plants. The function of rhizosphere hydrophobicity is not easily understandable when looking at a single plant, but it may constitute a competitive advantage at the ecosystem level. We hypothesize that by making the top soil hydrophobic, deep-rooted plants avoid competititon with shallow-rooted plants. To test this hypothesis we used an individual-based model to simulate water uptake and growth of two virtual plant species, one deep-rooted plant capable of making the soil hydrophobic and a shallow-rooted plant. We ran scenarios with different precipitation regimes ranging from dry to wet (350, 700, and 1400 mm total annual precipitation and from high to low precipitation frequencies (1, 7, and 14 days. Plant species abundance and biomass were chosen as indicators for competitiveness of plant species. At constant precipitation frequency mucilage hydrophobicity lead to a benefit in biomass and abundance of the tap-rooted population. Under wet conditions this effect diminished and tap-rooted plants were less productive. Without this trait both species coexisted. The effect of root exudation trait remained constant under different precipitation frequencies. This study shows that mucilage secretion is a competitive trait for the acquisition of water. This advantage is achieved by the modification of the soil hydraulic properties and specifically by inducing water repellency in soil regions which are shared with other species.

Japanese position paper on sodium-water reaction testing and design

International Nuclear Information System (INIS)

Sato, M.; Hiroi, H.; Tanabe, H.; Miyake, O.; Kuroha, M.; Hoshi, Y.

1984-01-01

PNC has been developing the steam generator with helically coiled heat transfer tube bundle and downcommer tubes for the prototype fast reactor Monju since 1968. To establish the safety design against the sodium-water reaction accident was one of the most important R and D items at the start of the development. PNC started the experimental study initially in the large leak region in 1970. Until now, during twelve years, the experimental studies have been performed, which covers the phenomena from a micro leak to a large one, with the use of the SWAT-1 rig, SWAT-2 loop, SWAT-3 loop, and SWAT-4 rigs. The reliable leak detection system is necessary to minimize the damage by the sodium-water reaction. Two groups of efforts have been paid for developing the detection system. One is to develop the leak detector itself, and another is to grasp the hydrogen transport behavior in the sodium in the steam generator and the secondary piping system. Four sodium loops have been used for the development. The development of computer codes has also progressed in parallel with the sodium-water reaction experiments. Three codes have been accomplished for the design tools against the sodium-water reaction. Through the efforts mentioned above, sufficient experiences were obtained for designing and operating the Monju steam generator system

Do Zebra Mussels Grow Faster on Live Unionids than on Inanimate Substrate? A Study with Field Enclosures

Science.gov (United States)

Hörmann, Leonhard; Maier, Gerhard

2006-05-01

The zebra mussel Dreissena polymorpha has invaded numerous freshwaters in Europe and North America and can foul many types of solid substrates, including unionid bivalves. In field experiments we compared growth rates of dreissenids on live specimens of the freshwater bivalve Anodonta cygnea to growth rates of dreissenids on stones. Dreissena density in the study lake was about 1000 m-2 in most places, Anodonta density approximately 1 m-2 and about 50% of the Anodonta were infested with 10-30 Dreissena . In summer/autumn small dreissenids generally grew faster on live Anodonta than on stones. Similar trends were observed for spring, but differences of growth increments between dreissenids on live Anodonta and stones were usually not significant. Dreissenids settled down or moved towards the ingestion/egestion siphons of Anodonta and ingestion siphons of dreissenids were directed towards siphons of Anodonta . These results suggest that dreissenids can use the food provided by the filter current of the large Anodonta .

The Politics of Scale, Position, and Place in the Governance of Water Resources in the Mekong Region

Directory of Open Access Journals (Sweden)

Louis Lebel

2005-12-01

Full Text Available The appropriate scales for science, management, and decision making cannot be unambiguously derived from physical characteristics of water resources. Scales are a joint product of social and biophysical processes. The politics-of-scale metaphor has been helpful in drawing attention to the ways in which scale choices are constrained overtly by politics, and more subtly by choices of technologies, institutional designs, and measurements. In doing so, however, the scale metaphor has been stretched to cover a lot of different spatial relationships. In this paper, we argue that there are benefits to understanding - and actions to distinguish - issues of scale from those of place and position. We illustrate our arguments with examples from the governance of water resources in the Mekong region, where key scientific information is often limited to a few sources. Acknowledging how actors' interests fit along various spatial, temporal, jurisdictional, and other social scales helps make the case for innovative and more inclusive means for bringing multi-level interests to a common forum. Deliberation can provide a check on the extent of shared understanding and key uncertainties.

Urbanizing rural waters

NARCIS (Netherlands)

Hommes, Lena; Boelens, Rutgerd

2017-01-01

This article studies how urbanization processes and associated rural-urban water transfers in the Lima region (Peru) create water control hierarchies that align the municipal drinking water company, hydropower plants and rural communities on unequal positions. By scrutinizing the history of water

Comparative assessment of the bacterial communities associated with Aedes aegypti larvae and water from domestic water storage containers.

Science.gov (United States)

Dada, Nsa; Jumas-Bilak, Estelle; Manguin, Sylvie; Seidu, Razak; Stenström, Thor-Axel; Overgaard, Hans J

2014-08-24

Domestic water storage containers constitute major Aedes aegypti breeding sites. We present for the first time a comparative analysis of the bacterial communities associated with Ae. aegypti larvae and water from domestic water containers. The 16S rRNA-temporal temperature gradient gel electrophoresis (TTGE) was used to identify and compare bacterial communities in fourth-instar Ae. aegypti larvae and water from larvae positive and negative domestic containers in a rural village in northeastern Thailand. Water samples were cultured for enteric bacteria in addition to TTGE. Sequences obtained from TTGE and bacterial cultures were clustered into operational taxonomic units (OTUs) for analyses. Significantly lower OTU abundance was found in fourth-instar Ae. aegypti larvae compared to mosquito positive water samples. There was no significant difference in OTU abundance between larvae and mosquito negative water samples or between mosquito positive and negative water samples. Larval samples had significantly different OTU diversity compared to mosquito positive and negative water samples, with no significant difference between mosquito positive and negative water samples. The TTGE identified 24 bacterial taxa, belonging to the phyla Proteobacteria, Firmicutes, Actinobacteria, Bacteroidetes and TM7 (candidate phylum). Seven of these taxa were identified in larval samples, 16 in mosquito positive and 13 in mosquito negative water samples. Only two taxa, belonging to the phyla Firmicutes and Actinobacteria, were common to both larvae and water samples. Bacilli was the most abundant bacterial class identified from Ae. aegypti larvae, Gammaproteobacteria from mosquito positive water samples, and Flavobacteria from mosquito negative water samples. Enteric bacteria belonging to the class Gammaproteobacteria were sparsely represented in TTGE, but were isolated from both mosquito positive and negative water samples by selective culture. Few bacteria from water samples were

Optimization of turbine positioning in water distribution networks. A Sicilian case study

Science.gov (United States)

Milici, Barbara; Messineo, Simona; Messineo, Antonio

2017-11-01

The potential energy of water in Water Distribution Networks (WDNs), is usually dissipated by Pressure Reduction Valves (PRVs), thanks to which water utilities manage the pressure level in selected nodes of the network. The present study explores the use of economic hydraulic machines, pumps as turbines (PATs), to produce energy in a small network with the aim to avoid dissipation in favour of renewable energy production. The proposed study is applied to a WDN located in a town close to Palermo (Sicily), where users often install private tanks, to collect water during the period of water scarcity conditions. As expected, the economic benefit of PATs installation in WDNs is affected by the presence of private tanks, whose presence deeply modifies the network from designed condition. The analysis is carried out by means of a mathematical model, which is able to simulate dynamically water distribution networks with private tanks and PATs. As expected, the advantage of PATs' installation in terms of renewable energy recovery is strictly conditioned by their placement in the WDN.

Buffer substitution in malaria rapid diagnostic tests causes false-positive results

Directory of Open Access Journals (Sweden)

Van den Ende Jef

2010-07-01

Full Text Available Abstract Background Malaria rapid diagnostic tests (RDTs are kits that generally include 20 to 25 test strips or cassettes, but only a single buffer vial. In field settings, laboratory staff occasionally uses saline, distilled water (liquids for parenteral drugs dilution or tap water as substitutes for the RDT kit's buffer to compensate for the loss of a diluent bottle. The present study assessed the effect of buffer substitution on the RDT results. Methods Twenty-seven RDT brands were run with EDTA-blood samples of five malaria-free subjects, who were negative for rheumatoid factor and antinuclear antibodies. Saline, distilled water and tap water were used as substitute liquids. RDTs were also run with distilled water, without adding blood. Results were compared to those obtained with the RDT kit's buffer and Plasmodium positive samples. Results Only eight cassettes (in four RDT brands showed no control line and were considered invalid. Visible test lines occurred for at least one malaria-free sample and one of the substitutes in 20/27 (74% RDT brands (saline: n = 16; distilled water: n = 17; and tap water: n = 20, and in 15 RDTs which were run with distilled water only. They occurred for all Plasmodium antigens and RDT formats (two-, three- and four-band RDTs. Clearance of the background of the strip was excellent except for saline. The aspects (colour, intensity and crispness of the control and the false-positive test lines were similar to those obtained with the RDT kits' buffer and Plasmodium positive samples. Conclusion Replacement of the RDT kit's dedicated buffer by saline, distilled water and tap water can cause false-positive test results.

Protection against suspended sand: the function of the branchial membrane in the blue mussel Mytilus edulis

Science.gov (United States)

de Vooys, C. G. N.

2006-09-01

Blue mussels ( Mytilus edulis) living in estuaries have to cope with varying concentrations of suspended sand. Sand flowing through the inhalant siphons comes into the infrabranchial chamber. The inhalant siphon can be partially closed by the branchial membrane. As a result the inward flow decreases, and suspended sand sinks and can be eliminated. Experiments with mussels from three ecologically different locations showed about the same response of the branchial membrane on contact with suspended sand. The presence and function of the branchial membrane appears to be an adaptation of mussels to their estuarine environment.

Position of residues in transmembrane peptides with respect to the lipid bilayer: A combined lipid NOEs and water chemical exchange approach in phospholipid bicelles

International Nuclear Information System (INIS)

Glover, Kerney Jebrell; Whiles, Jennifer A.; Vold, Regitze R.; Melacini, Giuseppe

2002-01-01

The model transmembrane peptide P16 was incorporated into small unaligned phospholipid bicelles, which provide a 'native-like' lipid bilayer compatible with high-resolution solution NMR techniques. Using amide-water chemical exchange and amide-lipid cross-relaxation measurements, the interactions between P16 and bicelles were investigated. Distinctive intermolecular NOE patterns observed in band-selective 2D-NOESY spectra of bicellar solutions with several lipid deuteration schemes indicated that P16 is preferentially interacting with the 'bilayered' region of the bicelle rather than with the rim. Furthermore, when amide-lipid NOEs were combined with amide-water chemical exchange cross-peaks of selectively 15 N-labeled P16 peptides, valuable information was obtained about the position of selected residues relative to the membrane-water interface. Specifically, three main classes were identified. Class I residues lie outside the bilayer and show amide-water exchange cross-peaks but no amide-lipid NOEs. Class II residues reside in the bilayer-water interface and show both amide-water exchange cross-peaks and amide-lipid NOEs. Class III residues are embedded within the hydrophobic core of the membrane and show no amide-water exchange cross-peaks but strong amide-lipid NOEs

Position-dependency of Fuel Pin Homogenization in a Pressurized Water Reactor

Energy Technology Data Exchange (ETDEWEB)

Heo, Woong; Kim, Yonghee [Korea Advanced Institute of Science and Technolgy, Daejeon (Korea, Republic of)

2016-05-15

By considering the multi-physics effects more comprehensively, it is possible to acquire precise local parameters which can result in a more accurate core design and safety assessment. A conventional approach of the multi-physics neutronics calculation for the pressurized water reactor (PWR) is to apply nodal methods. Since the nodal methods are basically based on the use of assembly-wise homogenized parameters, additional pin power reconstruction processes are necessary to obtain local power information. In the past, pin-by-pin core calculation was impractical due to the limited computational hardware capability. With the rapid advancement of computer technology, it is now perhaps quite practical to perform the direct pin-by-pin core calculation. As such, fully heterogeneous transport solvers based on both stochastic and deterministic methods have been developed for the acquisition of exact local parameters. However, the 3-D transport reactor analysis is still challenging because of the very high computational requirement. Position-dependency of the fuel pin homogenized cross sections in a small PWR core has been quantified via comparison of infinite FA and 2-D whole core calculations with the use of high-fidelity MC simulations. It is found that the pin environmental affect is especially obvious in FAs bordering the baffle reflector regions. It is also noted that the downscattering cross section is rather sensitive to the spectrum changes of the pins. It is expected that the pinwise homogenized cross sections need to be corrected somehow for accurate pin-by-pin core calculations in the peripheral region of the reactor core.

The effect of spherical hub-nose position on pressure drop in an oscillating water column system for wave energy conversion

Energy Technology Data Exchange (ETDEWEB)

Taha, Z.; Ahmad, N.; Ghazilla, R.A.R.; Yap, H.J.; Ya, T.Y.T.; Passarella, R.; Hasanuddin, I.; Yunus, M. [Malaya Univ. (Malaysia). Centre for Product Design and Manufacturing; Sugiyono [Malaya Univ., (Malaysia). Centre for Product Design and Manufacturing; Gadjah Mada Univ. (Indonesia). Dept. of Mechanical and Industrial Engineering

2009-07-01

The use of renewable energy sources as an alternative to conventional fuels was discussed with particular reference to ocean wave energy and its potential to contribute to the energy requirements of coastal nations. Ocean wave energy has been harnessed and converted into electricity using processes and technologies that are environmentally sound. The oscillating water column (OWC) system is considered to be among the most promising technology for harnessing wave energy. This paper presented the results of a study that investigated the pressure drop in an OWC system and the effect of spherical hub-nose position in an annular duct. Computational fluid dynamics (CFD) analysis was used under steady flow conditions for several hub-nose positions to determine the characteristic of pressure drop. The study showed that the hub-nose position influenced the pressure drop in the OWC system. The highest value of the pressure drop in this study occurred when the hub-nose was at the position of 0.0 m relative to the end of the converging cone. The pressure drop decreased when the hub-nose position moved away from the end of converging cone. The lowest value occurred at the position of -0.5 m. It was concluded that despite the numerically small change in pressure drop, this phenomenon should be considered in the design process of the OWC system because of the operational condition of the system at low-pressure pneumatic power. The pressure drop actually reduces the amount of energy that will be converted by the air turbine. 9 refs., 2 tabs., 6 figs.

Control of the flow rate in decreasing of the water load of peat production

International Nuclear Information System (INIS)

Anon.

1995-01-01

The retention capacity and control of the flow rate was studied in the Aqua-Peat research. The sedimentation ability of solid matter (peat particles), erosion, migration of the solid matter, and the functioning of the retention pipes located in the strip ditches and the sedimentation basins were measured in the research. Detection was also supplemented by laboratory scale models and by measurements made using them. A model, describing the solid matter erosion and migration on the mire, was compiled on the basis of the results. Migration of the solid matter is possible to reduce by pounding the water into the ditching. So there is more time for particles to settle before migration into watercources. By this method it is possible to reduce the solid matter loads caused by heavy rains and power-flows even by 88 %. If the flow control system is equipped with retainers and settling basins, the solid matter retention capacity can rise up to 93-97 %. The results have shown that the retention pipe retainers play more important role in reduction of solid matter load than sedimentation basins. A follow-up study was made using several types of retainers. A 5 cm thick siphon pipe appeared to be the best. The final selection of the retention pipes has, however, to be made as a compromise between the functioning of the drying process, production possibilities and solid matter retention. (1 ref., 2 figs.)

Estimation of Oxidation Kinetics and Oxide Scale Void Position of Ferritic-Martensitic Steels in Supercritical Water

Directory of Open Access Journals (Sweden)

Li Sun

2017-01-01

Full Text Available Exfoliation of oxide scales from high-temperature heating surfaces of power boilers threatened the safety of supercritical power generating units. According to available space model, the oxidation kinetics of two ferritic-martensitic steels are developed to predict in supercritical water at 400°C, 500°C, and 600°C. The iron diffusion coefficients in magnetite and Fe-Cr spinel are extrapolated from studies of Backhaus and Töpfer. According to Fe-Cr-O ternary phase diagram, oxygen partial pressure at the steel/Fe-Cr spinel oxide interface is determined. The oxygen partial pressure at the magnetite/supercritical water interface meets the equivalent oxygen partial pressure when system equilibrium has been attained. The relative error between calculated values and experimental values is analyzed and the reasons of error are suggested. The research results show that the results of simulation at 600°C are approximately close to experimental results. The iron diffusion coefficient is discontinuous in the duplex scale of two ferritic-martensitic steels. The simulation results of thicknesses of the oxide scale on tubes (T91 of final superheater of a 600 MW supercritical boiler are compared with field measurement data and calculation results by Adrian’s method. The calculated void positions of oxide scales are in good agreement with a cross-sectional SEM image of the oxide layers.

Geostatistical Characteristic of Space -Time Variation in Underground Water Selected Quality Parameters in Klodzko Water Intake Area (SW Part of Poland)

Science.gov (United States)

Namysłowska-Wilczyńska, Barbara

2016-04-01

This paper presents selected results of research connected with the development of a (3D) geostatistical hydrogeochemical model of the Klodzko Drainage Basin, dedicated to the spatial and time variation in the selected quality parameters of underground water in the Klodzko water intake area (SW part of Poland). The research covers the period 2011÷2012. Spatial analyses of the variation in various quality parameters, i.e, contents of: ammonium ion [gNH4+/m3], NO3- (nitrate ion) [gNO3/m3], PO4-3 (phosphate ion) [gPO4-3/m3], total organic carbon C (TOC) [gC/m3], pH redox potential and temperature C [degrees], were carried out on the basis of the chemical determinations of the quality parameters of underground water samples taken from the wells in the water intake area. Spatial and time variation in the quality parameters was analyzed on the basis of archival data (period 1977÷1999) for 22 (pump and siphon) wells with a depth ranging from 9.5 to 38.0 m b.g.l., later data obtained (November 2011) from tests of water taken from 14 existing wells. The wells were built in the years 1954÷1998. The water abstraction depth (difference between the terrain elevation and the dynamic water table level) is ranged from 276÷286 m a.s.l., with an average of 282.05 m a.s.l. Dynamic water table level is contained between 6.22 m÷16.44 m b.g.l., with a mean value of 9.64 m b.g.l. The latest data (January 2012) acquired from 3 new piezometers, with a depth of 9÷10m, which were made in other locations in the relevant area. Thematic databases, containing original data on coordinates X, Y (latitude, longitude) and Z (terrain elevation and time - years) and on regionalized variables, i.e. the underground water quality parameters in the Klodzko water intake area determined for different analytical configurations (22 wells, 14 wells, 14 wells + 3 piezometers), were created. Both archival data (acquired in the years 1977÷1999) and the latest data (collected in 2011÷2012) were analyzed

Gastroesophageal reflux in children: radionuclide gastroesophagography

International Nuclear Information System (INIS)

Blumhagen, J.D.; Rudd, T.G.; Christie, D.L.

1980-01-01

Sixty-five symptomatic infants and children underwent radionuclide gastroesophagography, acid reflux testing, and barium esophagography with water-siphon testing to evaluate the clinical efficacy of the scintigraphic technique in detecting gastroesophageal reflux. After ingesting /sup 99m/Tc sulfur colloid in fruit juice, patients rested beneath the gamma camera for 30 to 60 min while esophageal activity was monitored continuously. By using the acid reflux test as a standard of comparison, the senstivity of radionuclide gastroesophagography was 75%. Because of its physiologic nature, low radiation exposure, and convenience, radionuclide gastroesophagography warrants further evaluation as a screening test for gastroesophageal reflux

Water level monitoring device in nuclear reactor

International Nuclear Information System (INIS)

Miura, Kiyohide; Otake, Tomohiro.

1988-01-01

Purpose: To monitor the water level in a pressure vessel of BWR type nuclear reactors at high accuracy by improving the compensation functions. Constitution: In the conventional water level monitor in a nuclear reactor, if the pressure vessel is displaced by the change of the pressure in the reactor or the temperature of the reactor water, the relative level of the reference water head in a condensation vessel is changed to cause deviation between the actual water level and the indicated water level to reduce the monitoring accuracy. According to the invention, means for detecting the position of the reference water head and means for detection the position in the condensation vessel are disposed to the pressure vessel. Then, relative positional change between the condensation vessel and the reference water head is calculated based on detection sinals from both of the means. The water level is compensated and calculated by water level calculation means based on the relative positional change, water level signals from the level gage and the pressure signals from the pressure gage. As a result, if the pressure vessel is displaced due to the change of the temperature or pressure, it is possible to measure the reactor water level accurately thereby remakably improve the reliability for the water level control in the nuclear reactor. (Horiuchi, T.)

Water Residence Time estimation by 1D deconvolution in the form of a l2 -regularized inverse problem with smoothness, positivity and causality constraints

Science.gov (United States)

Meresescu, Alina G.; Kowalski, Matthieu; Schmidt, Frédéric; Landais, François

2018-06-01

The Water Residence Time distribution is the equivalent of the impulse response of a linear system allowing the propagation of water through a medium, e.g. the propagation of rain water from the top of the mountain towards the aquifers. We consider the output aquifer levels as the convolution between the input rain levels and the Water Residence Time, starting with an initial aquifer base level. The estimation of Water Residence Time is important for a better understanding of hydro-bio-geochemical processes and mixing properties of wetlands used as filters in ecological applications, as well as protecting fresh water sources for wells from pollutants. Common methods of estimating the Water Residence Time focus on cross-correlation, parameter fitting and non-parametric deconvolution methods. Here we propose a 1D full-deconvolution, regularized, non-parametric inverse problem algorithm that enforces smoothness and uses constraints of causality and positivity to estimate the Water Residence Time curve. Compared to Bayesian non-parametric deconvolution approaches, it has a fast runtime per test case; compared to the popular and fast cross-correlation method, it produces a more precise Water Residence Time curve even in the case of noisy measurements. The algorithm needs only one regularization parameter to balance between smoothness of the Water Residence Time and accuracy of the reconstruction. We propose an approach on how to automatically find a suitable value of the regularization parameter from the input data only. Tests on real data illustrate the potential of this method to analyze hydrological datasets.

Cross-well 4-D resistivity tomography localizes the oil-water encroachment front during water flooding

Science.gov (United States)

Zhang, J.; Revil, A.

2015-04-01

The early detection of the oil-water encroachment front is of prime interest during the water flooding of an oil reservoir to maximize the production of oil and to avoid the oil-water encroachment front to come too close to production wells. We propose a new 4-D inversion approach based on the Gauss-Newton approach to invert cross-well resistance data. The goal of this study is to image the position of the oil-water encroachment front in a heterogeneous clayey sand reservoir. This approach is based on explicitly connecting the change of resistivity to the petrophysical properties controlling the position of the front (porosity and permeability) and to the saturation of the water phase through a petrophysical resistivity model accounting for bulk and surface conductivity contributions and saturation. The distributions of the permeability and porosity are also inverted using the time-lapse resistivity data in order to better reconstruct the position of the oil water encroachment front. In our synthetic test case, we get a better position of the front with the by-products of porosity and permeability inferences near the flow trajectory and close to the wells. The numerical simulations show that the position of the front is recovered well but the distribution of the recovered porosity and permeability is only fair. A comparison with a commercial code based on a classical Gauss-Newton approach with no information provided by the two-phase flow model fails to recover the position of the front. The new approach could be used for the time-lapse monitoring of various processes in both geothermal fields and oil and gas reservoirs using a combination of geophysical methods.

Review of design technology of control rod position indicators

International Nuclear Information System (INIS)

Yu, Je Yong; Huh, Hyung; Kim, Ji Ho; Kim, Jong In; Chang, Moon Hee

1999-10-01

An integral reactor SMART is under development at KAERI. The design characteristics of SMART are radically different from those employer in currently operating loop type water reactors in Korea. The objective of this report is to review the design technology of position indicator, and to study the various sensors which can be used in rod position indicator. Design criteria that rod position indicator should satisfy are also examined. Following position indicators are reviewed in this report. 1. Digital positioning indicator (DRPI), 2. Reed switch type position indicator (RSPT), 3. Choke sensor type position indicator, 4. Ultrasonic sensor type position indicator, 5. Comparison of each position indicator. (author)

Carboniferous Psammichnites: Systematic re-evaluation, taphonomy and autecology

Science.gov (United States)

Mángano, M. Gabriela; Rindsberg, Andrew K.

2002-01-01

The ichnogenus Psammichnites Torell 1870 includes a wide variety of predominantly horizontal, sinuous to looped, backfilled traces, characterized by a distinctive median dorsal structure. Though commonly preserved in full relief on upper bedding surfaces, some ichnospecies of Psammichnites may be preserved in negative hyporelief. Psammichnites records the feeding activities of a subsurface animal using a siphon-like device. Several ichnogenera reflect this general behavioral pattern, including Plagiogmus Roedel 1929 and the Carboniferous ichnogenera Olivellites Fenton and Fenton 1937a and Aulichnites Fenton and Fenton 1937b. Based on analysis of specimens from the United States, Spain, and the United Kingdom, three Carboniferous ichnospecies of Psammichnites are reviewed in this paper: P. plummeri (Fenton and Fenton, 1937a), P. grumula(Romano and Meléndez 1979), and P. implexus (Rindsberg 1994). Psammichnites plummeri is the most common Carboniferous ichnospecies and is characterized by a relatively straight, continuous dorsal ridge/groove, fine transverse ridges, larger size range, and non-looping geometric pattern. It represents a grazing trace of deposit feeders. Psammichnites grumula differs from the other ichnospecies of Psammichnitesby having median dorsal holes or protruding mounds. The presence of mounds or holes in P. grumulasuggests a siphon that was regularly connected to the sediment-water interface. This ichnospecies is interpreted as produced by a deposit feeder using the siphon for respiration or as a device for a chemosymbiotic strategy. Psammichnites implexus is characterized by its consistently smaller size range, subtle backfill structure, and tendency to scribble. Although displaying similarities with Dictyodora scotica, P. implexus is a very shallow-tier, grazing trace. Changes in behavioral pattern, preservational style, and bedform morphology suggest a complex interplay of ecological and taphonomic controls in

Position estimation of transceivers in communication networks

Science.gov (United States)

Kent, Claudia A [Pleasanton, CA; Dowla, Farid [Castro Valley, CA

2008-06-03

This invention provides a system and method using wireless communication interfaces coupled with statistical processing of time-of-flight data to locate by position estimation unknown wireless receivers. Such an invention can be applied in sensor network applications, such as environmental monitoring of water in the soil or chemicals in the air where the position of the network nodes is deemed critical. Moreover, the present invention can be arranged to operate in areas where a Global Positioning System (GPS) is not available, such as inside buildings, caves, and tunnels.

Water temperature impacts water consumption by range cattle in winter

Science.gov (United States)

Water consumption and DMI have been found to be positively correlated, which may interact with ingestion of cold water or grazed frozen forage due to transitory reductions in temperature of ruminal contents. The hypothesis underpinning the study explores the potential that cows provided warm drinkin...

Positions of human dwellings affect few tropical diseases near ...

African Journals Online (AJOL)

user

Some factors that possibly affect tropical disease distribution was investigated in about 500 randomize human dwellings. The studied factors include wild animals, domestic animals, wild plants, cultivated plants, nature of soil, nature of water, positions of human dwellings, nature of building material and position of animal ...

Recovering oil from shale

Energy Technology Data Exchange (ETDEWEB)

Leahey, T; Wilson, H

1920-11-13

To recover oil free from inorganic impurities and water, and utilize the oil vapor and tarry matter for the production of heat, shale is heated in a retort at a temperature of not less than 120/sup 0/C. The vapors pass by a pipe into a water jacketed condenser from which the condensate and gas pass through a pipe into a chamber and then by a pipe to a setting chamber from where the light oils are decanted through a pipe into a tank. The heavy oil is siphoned through a pipe into a tank, while the gas passes through a pipe into a scrubber and then into a drier, exhauster and pipe to the flue and ports, above the fire-bars, into the retort. Air is introduced through a pipe, flue, and ports.

Computational Studies of Positive and Negative Streamers in Bubbles Suspended in Distilled Water

KAUST Repository

Sharma, Ashish; Levko, Dmitry; Raja, Laxminarayan L.

2017-01-01

We perform computational studies of nanosecond streamers generated in helium bubbles immersed in distilled water under high pressure conditions. The model takes into account the presence of water vapor in the gas bubble for an accurate description

Turbulence and heat transfer in condensate in drying cylinders at high g-forces. Phase 2; Turbulens och vaermeoeverfoering i kondensat i torkcylindrar vid hoega g-krafter. Fas 2

Energy Technology Data Exchange (ETDEWEB)

Stenstroem, Stig; Ingvarsson, David [Lund Inst. of Tech. (Sweden). Dept. of Chemical Engineering

2006-02-15

During paper drying a condensate layer is formed on the inside surface of the rotating cylinder which acts as resistance for heat transfer through the cylinder. The heat transfer resistance in the condensate layer is mainly dependant on the layer thickness and the turbulence in the layer. Consequently the resistance increases with higher cylinder speeds due to increased centrifugal forces and thus reduced turbulence in the layer. In order to minimize the influence of condensate on the heat transfer process the cylinder used in Phase 1 has been equipped with axial grooves. The aim of the project has been to study the water movement in the cylinder and to investigate how the drying capacity is influenced by condensate accumulating in the grooves rather than moving along the smooth surface of a paper dryer cylinder. This knowledge should be considered preferably before construction of cylinders for new machines. For existing machines with smooth cylinders the importance of axial vertical flanges for improved heat transfer has been investigated. In addition the capacity of stationary siphons has been evaluated. The results are of importance for the manufacturers of paper machines as well as the producing newsprint and printing paper companies. According to the results from the experiments the water flows mainly in the grooves, assuming that the number of grooves and that the dimensions of the grooves are adjusted to the water load. Then the surfaces between the grooves can be considered as completely dry unlike in a smooth cylinder where the surfaces more or less are covered with a thin layer of condensate. Furthermore the centrifugal force helps the water to flow down into the grooves. Consequently a high water flow will rely on a high cylinder speed in order to keep the water flowing into the axial grooves. The computer simulations show that the drying capacity increases with up to 46 % in dryer cylinders provided with axial grooves compared to smooth cylinders

The use of dilute calogen[reg] as a fat density oral contrast medium in upper abdominal computed tomography, compared with the use of water and positive oral contrast media

International Nuclear Information System (INIS)

Ramsay, Duncan W.; Markham, Derrian H.; Morgan, Bruno; Rodgers, Peter M.; Liddicoat, Amanda J.

2001-01-01

AIM: Oral contrast media are commonly given prior to computed tomography (CT) examination of the upper abdomen. Although positive oral contrast media are normally used, there is increasing interest in using negative agents such as water and less commonly fat density products. The aim of this study was to compare a positive oral contrast medium, water, and a diluted emulsion of arachis oil (Calogen[reg], a fat density food supplement) for assessment of the upper abdomen. MATERIALS AND METHODS: Seventy-one patients referred for upper abdominal CT were randomized to receive either 500 ml water, 2% sodium diatrizoate or a dilute suspension of Calogen[reg]. The CT images were scored independently by three radiologists. Distension and anatomical identification was assessed for the stomach, duodenum and jejunum; with anatomical identification recorded for the pancreas, retroperitoneum, liver, gallbladder and spleen. RESULTS: Dilute Calogen[reg] produced a significant improvement (P < 0.01) in distension and anatomical visualization of the stomach and proximal duodenum. Only minimal differences were demonstrated between the three contrast media for visualization of more distal small bowel or identification of the other upper abdominal viscera. Significantly more artifacts were caused by positive contrast media than with the Calogen[reg] mixture. CONCLUSION: A dilute suspension of Calogen[reg] as an oral contrast medium is recommended when disease is suspected within the stomach or proximal duodenum. Ramsay, D.W. et al. (2001)

The exhalant jet of mussels Mytilus edulis

DEFF Research Database (Denmark)

Riisgard, Hans Ulrik; Jørgensen, Bo Hoffmann; Lundgreen, Kim

2011-01-01

shell lengths. Here, we present results of a detailed study of fully open mussels Mytilus edulis in terms of filtration rate, exhalant siphon aperture area, jet velocity, gill area and body dry weight, all as a function of shell length (mean +/- SD) over the range 16.0 +/- 0.4 to 82.6 +/- 2.9 mm...... detailed 2-component velocity distributions near the exhalant siphon in 5 planes parallel to the axis of the jet and the major axis of the oval aperture, and hence estimates of momentum and kinetic energy flows in addition to mean velocity. Data obtained on particles inside the exhalant jet of filtered...

Access to the ophthalmic artery by retrograde approach through the posterior communicating artery for intra-arterial chemotherapy of retinoblastoma

Energy Technology Data Exchange (ETDEWEB)

Pham, Chi-Tuan; Blanc, Raphael; Pistocchi, Silvia; Bartolini, Bruno; Piotin, Michel [Fondation Rothschild Hospital, Department of Interventional Neuroradiology, Paris (France); Lumbroso-Le Rouic, Livia [Institut Curie, Department of Ocular Oncology, Paris (France)

2012-08-15

Intra-arterial infusion of chemotherapy into the ophthalmic artery for treatment of retinoblastoma has been realized after catheterization of the internal carotid and temporary balloon occlusion beyond the orifice of the ophthalmic artery, or more recently after superselective canulation of the ophthalmic artery by a microcatheter. The superselective catheterization of the ophthalmic artery could be cumbersome because of the implantation of the ostium on the carotid siphon or because of the tortuosity of the carotid siphon. We report our experience of using a retrograde approach through the posterior communicating artery that allows a more direct angle of access to the origin of the ophthalmic artery. (orig.)

Experimental fast reactor JOYO MK-III functional test. Primary auxiliary cooling system test

International Nuclear Information System (INIS)

Karube, Koji; Akagi, Shinji; Terano, Toshihiro; Onuki, Osamu; Ito, Hideaki; Aoki, Hiroshi; Odo, Toshihiro

2004-03-01

This paper describes the results of primary auxiliary cooling system, which were done as a part of JOYO MK-III function test. The aim of the tests was to confirm the operational performance of primary auxiliary EMP and the protection system including siphon breaker of primary auxiliary cooling system. The items of the tests were: (Test No.): (Test item). 1) SKS-117: EMP start up test. 2) SKS-118-1: EMP start up test when pony motor running. 3) SKS-121: Function test of siphon breaker. The results of the tests satisfied the required performance, and demonstrated successful operation of primary auxiliary cooling system. (author)

Quantifying the influence of environmental and water conservation attitudes on household end use water consumption.

Science.gov (United States)

Willis, Rachelle M; Stewart, Rodney A; Panuwatwanich, Kriengsak; Williams, Philip R; Hollingsworth, Anna L

2011-08-01

Within the research field of urban water demand management, understanding the link between environmental and water conservation attitudes and observed end use water consumption has been limited. Through a mixed method research design incorporating field-based smart metering technology and questionnaire surveys, this paper reveals the relationship between environmental and water conservation attitudes and a domestic water end use break down for 132 detached households located in Gold Coast city, Australia. Using confirmatory factor analysis, attitudinal factors were developed and refined; households were then categorised based on these factors through cluster analysis technique. Results indicated that residents with very positive environmental and water conservation attitudes consumed significantly less water in total and across the behaviourally influenced end uses of shower, clothes washer, irrigation and tap, than those with moderately positive attitudinal concern. The paper concluded with implications for urban water demand management planning, policy and practice. Crown Copyright © 2011. Published by Elsevier Ltd. All rights reserved.

46 CFR 169.555 - Emergency position indicating radio beacon (EPIRB).

Science.gov (United States)

2010-10-01

... 46 Shipping 7 2010-10-01 2010-10-01 false Emergency position indicating radio beacon (EPIRB). 169.555 Section 169.555 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) NAUTICAL SCHOOLS... Emergency position indicating radio beacon (EPIRB). (a) Each vessel certificated for exposed waters must...

Control rod position fault diagnosis and its software realization of pressurized water reactor

International Nuclear Information System (INIS)

Chang Zhengke; Shao Dinghong

2004-11-01

PLC software is adopted in the Rod Position Monitoring System of QS2NPS. By this software, the position of control rods can be monitored in real time, the abnormal phenomena can be identified immediately, the correctness and timeliness of fault diagnosis are improved remarkably. the identification and recordance of rod position fault, the performance validation of measure channel are realized also. The function and effect of this software are introduced. (authors)

Digital, electromagnetic rod position indicator with compensation

International Nuclear Information System (INIS)

Feilchenfeld, M.M.; Geis, C.G.

1985-01-01

A digital rod position indicator having discrete coils L 0 , L 1 , L 2 ..... spaced along the travel path of an elongate magnetically permeable member stores in digital form compensation signals for automatically adjusting the location relative to the coils at which a digital output signal representative of the position of the end of the elongate member transitions from one code to the next. The appropriate compensation signal is addressed using the digital output signal and a correction factor which takes into account the direction of movement including reversals. Reference is made to the positioning of the control rods in a pressurized water reactor. (author)

Countercurrent air/water and steam/water flow above a perforated plate. Report for October 1978-October 1979

International Nuclear Information System (INIS)

Hsieh, C.; Bankoff, S.G.; Tankin, R.S.; Yuen, M.C.

1980-11-01

The perforated plate weeping phenomena have been studied in both air/water and steam/cold water systems. The air/water experiment is designed to investigate the effect of geometric factors of the perforated plate on the rate of weeping. A new dimensionless flow rate in the form of H star is suggested. The data obtained are successfully correlated by this H star scaling in the conventional flooding equation. The steam/cold water experiment is concentrated on locating the boundary between weeping and no weeping. The effects of water subcooling, water inlet flow rate, and position of water spray are investigated. Depending on the combination of these factors, several types of weeping were observed. The data obtained at high water spray position can be related to the air/water flooding correlation by replacing the stream flow rate to an effective stream flow rate, which is determined by the mixing efficiency above the plate

Jugular venous pooling during lowering of the head affects blood pressure of the anesthetized giraffe

DEFF Research Database (Denmark)

Brøndum, E.; Hasenkam, John Michael; Secher, Niels H.

2009-01-01

How blood flow and pressure to the giraffe's brain are regulated when drinking remains debated. We measured simultaneous blood flow, pressure, and cross-sectional area in the carotid artery and jugular vein of five anesthetized and spontaneously breathing giraffes. The giraffes were suspended...... veins collapsed and blood was returned to the central circulation, and CVP and cardiac output were restored. The results demonstrate that in the upright-positioned, anesthetized giraffe cerebral blood flow is governed by arterial pressure without support of a siphon mechanism and that when the head...... in the upright position so that we could lower the head. In the upright position, mean arterial pressure (MAP) was 193 +/- 11 mmHg (mean +/- SE), carotid flow was 0.7 +/- 0.2 l/min, and carotid cross-sectional area was 0.85 +/- 0.04 cm(2). Central venous pressure (CVP) was 4 +/- 2 mmHg, jugular flow was 0...

Anodic electrode position of cyanometallates as sample preparation for the determination of transition metals from water samples using X-ray fluorescence analysis

International Nuclear Information System (INIS)

Wundt, K.; Duschner, H.; Starke, K.

1978-01-01

The anodic separation of cyanometallates of propanol -2/Water mixtures at high electrical field strengths was developed as new technique for sample preparation. The optimization of the parameters of the system (high voltage applied, current density, separation time and composition of the solution) resulted in quantitative precipitation of the metallates of Fe, Co, Ni, Cu, Zn, Cd and Ag in homogeneous, thin and strong-adhering layer with mass densities of between 1 nmol cm -2 and 1 μmol cm -2 on high-purity aluminium foils. Metals not forming anionic complexes remain in solution with simualtaneous quantitative multielement separation. The described technique is part of a method to determine heavy metal traces in water samples. It comprises the nonspecific sorption on cation exchangers, the elution of the transition metals as cyanometallates, their electrode position on aluminium foil and the determination by X-ray fluorescence analysis. Model experiments illustrate the possible applications of the method. (orig.) [de

Nitrogen Availability Dampens the Positive Impacts of CO2 Fertilization on Terrestrial Ecosystem Carbon and Water Cycles

Science.gov (United States)

He, Liming; Chen, Jing M.; Croft, Holly; Gonsamo, Alemu; Luo, Xiangzhong; Liu, Jane; Zheng, Ting; Liu, Ronggao; Liu, Yang

2017-11-01

The magnitude and variability of the terrestrial CO2 sink remain uncertain, partly due to limited global information on ecosystem nitrogen (N) and its cycle. Without N constraint in ecosystem models, the simulated benefits from CO2 fertilization and CO2-induced increases in water use efficiency (WUE) may be overestimated. In this study, satellite observations of a relative measure of chlorophyll content are used as a proxy for leaf photosynthetic N content globally for 2003-2011. Global gross primary productivity (GPP) and evapotranspiration are estimated under elevated CO2 and N-constrained model scenarios. Results suggest that the rate of global GPP increase is overestimated by 85% during 2000-2015 without N limitation. This limitation is found to occur in many tropical and boreal forests, where a negative leaf N trend indicates a reduction in photosynthetic capacity, thereby suppressing the positive vegetation response to enhanced CO2 fertilization. Based on our carbon-water coupled simulations, enhanced CO2 concentration decreased stomatal conductance and hence increased WUE by 10% globally over the 1982 to 2015 time frame. Due to increased anthropogenic N application, GPP in croplands continues to grow and offset the weak negative trend in forests due to N limitation. Our results also show that the improved WUE is unlikely to ease regional droughts in croplands because of increases in evapotranspiration, which are associated with the enhanced GPP. Although the N limitation on GPP increase is large, its associated confidence interval is still wide, suggesting an urgent need for better understanding and quantification of N limitation from satellite observations.

Neck length and mean arterial pressure in the sauropod dinosaurs.

Science.gov (United States)

Hughes, Stephen; Barry, John; Russell, Jeremy; Bell, Robert; Gurung, Som

2016-04-15

How blood was able to reach the heads of the long-necked sauropod dinosaurs has long been a matter of debate and several hypotheses have been presented. For example, it has been proposed that sauropods had exceptionally large hearts, multiple 'normal' sized hearts spaced at regular intervals up the neck or held their necks horizontal, or that the siphon effect was in operation. By means of an experimental model, we demonstrate that the siphon principle is able to explain how blood was able to adequately perfuse the sauropod brain. The return venous circulation may have been protected from complete collapse by a structure akin to the vertebral venous plexus. We derive an equation relating neck height and mean arterial pressure, which indicates that with a mean arterial pressure similar to that of the giraffe, the maximum safe vertical distance between heart and head would have been about 12 m. A hypothesis is presented that the maximum neck length in the fossil record is due to the siphon height limit. The equation indicates that to migrate over high ground, sauropods would have had to either significantly increase their mean arterial pressure or keep their necks below a certain height dependent on altitude. © 2016. Published by The Company of Biologists Ltd.

Water splitting and the band edge positions of TiO2

Czech Academy of Sciences Publication Activity Database

Deák, P.; Kullgren, J.; Aradi, B.; Frauenheim, T.; Kavan, Ladislav

2016-01-01

Roč. 199, MAY 2016 (2016), s. 27-34 ISSN 0013-4686 R&D Projects: GA ČR GA13-07724S Grant - others:COST(XE) CM1104 Institutional support: RVO:61388955 Keywords : water splitting * rutile * anatase Subject RIV: CG - Electrochemistry Impact factor: 4.798, year: 2016

Comparing microbial water quality in an intermittent and continuous piped water supply.

Science.gov (United States)

Kumpel, Emily; Nelson, Kara L

2013-09-15

Supplying piped water intermittently is a common practice throughout the world that increases the risk of microbial contamination through multiple mechanisms. Converting an intermittent supply to a continuous supply has the potential to improve the quality of water delivered to consumers. To understand the effects of this upgrade on water quality, we tested samples from reservoirs, consumer taps, and drinking water provided by households (e.g. from storage containers) from an intermittent and continuous supply in Hubli-Dharwad, India, over one year. Water samples were tested for total coliform, Escherichia coli, turbidity, free chlorine, and combined chlorine. While water quality was similar at service reservoirs supplying the continuous and intermittent sections of the network, indicator bacteria were detected more frequently and at higher concentrations in samples from taps supplied intermittently compared to those supplied continuously (p supply, with 0.7% of tap samples positive compared to 31.7% of intermittent water supply tap samples positive for E. coli. In samples from both continuously and intermittently supplied taps, higher concentrations of total coliform were measured after rainfall events. While source water quality declined slightly during the rainy season, only tap water from intermittent supply had significantly more indicator bacteria throughout the rainy season compared to the dry season. Drinking water samples provided by households in both continuous and intermittent supplies had higher concentrations of indicator bacteria than samples collected directly from taps. Most households with continuous supply continued to store water for drinking, resulting in re-contamination, which may reduce the benefits to water quality of converting to continuous supply. Copyright © 2013 Elsevier Ltd. All rights reserved.

Water conservation quantities vs customer opinion and satisfaction with water efficient appliances in Miami, Florida.

Science.gov (United States)

Lee, Mengshan; Tansel, Berrin

2013-10-15

During 2006-2007, Miami-Dade County, Florida, USA, provided incentives for low income and senior residents in single family homes for retrofitting with high efficiency fixtures. The participating residences were retrofitted with high-efficiency toilets, showerheads, and aerators. In 2012, a telephone survey was conducted to evaluate the satisfaction of the participants and the associated effects on water conservation practices. This study evaluates the attitudes and opinions of the participants relative to water use efficiency measures and the actual reduction in water consumption characteristics of the participating households. The participant characteristics were analyzed to identify correlations between the socio-demographic factors, program satisfaction and actual water savings. Approximately 65.5% of the survey respondents reported changes in their water use habits and 76.6% reported noticeable reduction in their water bills. The analyses showed that the satisfaction levels of the participants were closely correlated with the actual water savings. The results also showed that satisfaction level along with water saving potential (i.e., implementation of water efficiency devices) or change of water use habits has provided positive synergistic effect on actual water savings. The majority of the participants surveyed (81.3-89.1%) reported positive attitudes for water conservation incentive program and the benefits of the high efficiency fixtures. Copyright © 2013 Elsevier Ltd. All rights reserved.

Analysis of Health Indicators in Two Rural Communities on the Colombian Caribbean Coast: Poor Water Supply and Education Level Are Associated with Water-Related Diseases.

Science.gov (United States)

Ruiz-Díaz, María Stephany; Mora-García, Gustavo José; Salguedo-Madrid, Germán Israel; Alario, Ángelo; Gómez-Camargo, Doris Esther

2017-11-01

Water-related diseases are closely linked with drinking water, sanitation, and hygiene (WASH) indicators, socioeconomic status, education level, or dwelling's conditions. Developing countries exhibit a particular vulnerability to these diseases, especially rural areas and urban slums. This study assessed socioeconomic features, WASH indicators, and water-related diseases in two rural areas of the Colombian Caribbean coast. Most of this population did not finish basic education (72.3%, N = 159). Only one of the communities had a water supply (aqueduct), whereas the other received water via an adapted tanker ship. No respondents reported sewage services; 92.7% ( N = 204) had garbage service. Reported cases of diarrhea were associated with low education levels ( P = 2.37 × 10 -9 ) and an unimproved drinking water supply ( P = 0.035). At least one fever episode was reported in 20% ( N = 44) of dwellings, but the cases were not related to any indicator. The Aedes/ House index (percentage of houses that tested positive for Aedes larvae and/or pupae) was 69%, the container index (percentage of water-holding containers positive for Aedes larvae or pupae) 29.4%, and the Breteau index (number of positive containers per 100 houses in a specific location) was three positive containers per 100 inspected houses. The presence of positive containers was associated with the absence of a drinking water supply ( P = 0.04). The community with poorer health indicators showed greater health vulnerability conditions for acquisition of water-related diseases. In summary, water supply and educational level were the main factors associated with the presence of water-related diseases in both communities.

Comparison of neutral and positive enteral contrast media for MDCT enteroclysis

International Nuclear Information System (INIS)

Aiyappan, Senthil Kumar; Kalra, Naveen; Sandhu, Manavjit Singh; Kochhar, Rakesh; Wig, Jai Dev; Khandelwal, Niranjan

2012-01-01

Objective: To compare neutral and positive enteral contrast media for MDCT enteroclysis (MDCTE) in various small bowel diseases. Materials and methods: 40 patients with suspicion of small bowel diseases were divided randomly into two equal groups. In one group, water was used as neutral enteral contrast and in other group, 2% water soluble iodinated contrast was used as positive enteral contrast. All MDCTE were done on a 16-slice multidetector row CT unit. The findings of MDCTE were compared with the standards of reference. Results: There were 12 cases of abdominal tuberculosis (30%), 5 cases of bowel masses (12%), 4 cases of Crohn's disease (10%), 3 cases of small bowel adhesions (7%), 2 cases of midgut volvulus (5%), 2 cases of segmental enteritis (5%) and 12 of all cases (30%) were normal. There was no statistically significant difference between neutral and positive enteral contrast with regards to bowel distention, contrast reflux and evaluation of duodenum. Abnormal bowel wall enhancement was appreciated only with use of neutral enteral contrast (n = 12). Evaluation of ileocaecal junction was possible in all 20 patients (100%) with positive enteral contrast but in only 17 patients (85%) with neutral enteral contrast. Overall sensitivity and specificity of MDCTE with use of neutral contrast medium (100 and 88% respectively) was greater for evaluation of small bowel diseases, when compared to MDCTE using positive enteral contrast medium (92.8 and 83.3% respectively). Conclusions: Water is a good enteral contrast medium for MDCT enteroclysis examination and allows better evaluation of abnormal bowel wall enhancement. Ileocaecal junction evaluation is better with positive enteral contrast medium.

Sustainable Soil Water Management Systems

OpenAIRE

Basch, G.; Kassam, A.; Friedrich, T.; Santos, F.L.; Gubiani, P.I.; Calegari, A.; Reichert, J.M.; dos Santos, D.R.

2012-01-01

Soil quality and its management must be considered as key elements for an effective management of water resources, given that the hydrological cycle and land management are intimately linked (Bossio et al. 2007). Soil degradation has been described by Bossio et al. (2010) as the starting point of a negative cycle of soil-water relationships, creating a positive, self-accelerating feedback loop with important negative impacts on water cycling and water productivity. Therefore, sustainable soil...

14 CFR 25.523 - Design weights and center of gravity positions.

Science.gov (United States)

2010-01-01

... 14 Aeronautics and Space 1 2010-01-01 2010-01-01 false Design weights and center of gravity... Design weights and center of gravity positions. (a) Design weights. The water load requirements must be...) must be used. (b) Center of gravity positions. The critical centers of gravity within the limits for...

Trace of a water droplet exerted by coulomb force. 2

International Nuclear Information System (INIS)

Sugita, Hideaki; Murakami, Takuro; Nakazawa, Takeshi; Nakasako, Makoto; Yoshimura, Takuma; Osarakawa, Toshihiro

2002-01-01

The movement of water droplets in the air-water separator is based on the principle of the electrostatic precipitator with positive and negative poles. The mechanism of separation is that the water droplets charged negative ions or electrons by corona discharge are collected on the positive pole by Coulomb force operating between the both poles. This paper describes the theoretical analyses that how the movement of a water droplet is affected by Coulomb force in the air-water separator. (author)

Evaluation of accuracy in target positions of multmodality imaging using brain phantom

Energy Technology Data Exchange (ETDEWEB)

Juh, R. H.; Suh, T. S.; Chung, Y. A. [The Catholic University of Korea, Seoul (Korea, Republic of)

2002-07-01

Determination of target positions in radiation therapy or radiosurgery is critical to the successful treatment. It is often difficult to recognize the target position only from single image modality since each image modality has unique image pattern and image distortion problem. The purpose of this study is to evaluate the accuracy of target positions with multimodality brain phantom. We obtained CT, MR, and SPECT scan images with the specially designed brain phantom. Brain phantom consists of brain for images and frame for localization. The phantom was a water fillable cylinder containing 58 axial layers of 2.0 mm thickness. Each layer allows water to permeate various regions to match gray matter to white matter of 1:1 ratio. Localization frame with 5mm inner diameter and 150/160 mm length were attached to the outside of the brain slice and inside of the phantom cylinder. The phantom was filled with 0.16 M CuSO{sub 4} solution for MRI scan, and distilled water for CT and 15mCi (555 MBq) Tc-99m for SPECT. Axial slice images and volume images including the targets and localizer were obtained for each modality. To evaluate the errors in target positions, the position of localization and target balls measured in SPECT were compared with MR and CT. Transformation parameters for translation, rotation and scaling were determined by surface matching each SPECT with MR and CT images. Multimodality phantom was very useful to evaluate the accuracy of target positions among the different types of image modality such as CT, MR and SPECT.

Impact of Yangtze river water transfer on the water quality of the Lixia river watershed, China.

Directory of Open Access Journals (Sweden)

Xiaoxue Ma

Full Text Available To improve water quality and reduce the negative impacts of sudden inputs of water pollution in the Lixia River watershed, China, a series of experimental water transfers from the Yangtze River to the Lixia River were conducted from 2 December 2006 to 7 January 2007. Water samples were collected every six days at 55 monitoring sites during this period. Eight water parameters (water temperature, pH, dissolved oxygen (DO, chemical oxygen demand (COD, potassium permanganate index (CODMn, ammonia nitrogen (NH4+-N, electrical conductivity (EC, and water transparency (WT were analyzed to determine changes in nutrient concentrations during water transfers. The comprehensive pollution index (Pi and single-factor (Si evaluation methods were applied to evaluate spatio-temporal patterns of water quality during water transfers. Water quality parameters displayed different spatial and temporal distribution patterns within the watershed. Water quality was improved significantly by the water transfers, especially for sites closer to water intake points. The degree of improvement is positively related to rates of transfer inflow and drainage outflow. The effects differed for different water quality parameters at each site and at different water transfer times. There were notable decreases in NH4+-N, DO, COD, and CODMn across the entire watershed. However, positive effects on EC and pH were not observed. It is concluded that freshwater transfers from the Yangtze River can be used as an emergency measure to flush pollutants from the Lixia River watershed. Improved understanding of the effects of water transfers on water quality can help the development and implementation of effective strategies to improve water quality within this watershed.

Virtual water and water self-sufficiency in agricultural and livestock products in Brazil.

Science.gov (United States)

da Silva, Vicente de Paulo R; de Oliveira, Sonaly D; Braga, Célia C; Brito, José Ivaldo B; de Sousa, Francisco de Assis S; de Holanda, Romildo M; Campos, João Hugo B C; de Souza, Enio P; Braga, Armando César R; Rodrigues Almeida, Rafaela S; de Araújo, Lincoln E

2016-12-15

Virtual water trade is often considered a solution for restricted water availability in many regions of the world. Brazil is the world leader in the production and export of various agricultural and livestock products. The country is either a strong net importer or a strong net exporter of these products. The objective of this study is to determine the volume of virtual water contained in agricultural and livestock products imported/exported by Brazil from 1997 to 2012, and to define the water self-sufficiency index of agricultural and livestock products in Brazil. The indexes of water scarcity (WSI), water dependency (WDI) and water self-sufficiency (WSSI) were calculated for each Brazilian state. These indexes and the virtual water balance were calculated following the methodology developed by Chapagain and Hoekstra (2008) and Hoekstra and Hung (2005). The total water exports and imports embedded in agricultural and livestock products were 5.28 × 10 10 and 1.22 × 10 10  Gm 3  yr -1 , respectively, which results in positive virtual water balance of 4.05 × 10 10  Gm 3  yr -1 . Brazil is either a strong net importer or a strong net exporter of agricultural and livestock products among the Mercosur countries. Brazil has a positive virtual water balance of 1.85 × 10 10  Gm 3  yr -1 . The indexes used in this study reveal that Brazil is self-sufficient in food production, except for a few products such as wheat and rice. Horticultural products (tomato, onion, potato, cassava and garlic) make up a unique product group with negative virtual water balance in Brazil. Copyright © 2016 Elsevier Ltd. All rights reserved.

A digital position-indication system for control rods

International Nuclear Information System (INIS)

Nishizawa, Yukio; Hayakawa, Toshifumi

1979-01-01

Systems that detect and indicate the position of the control rods that regulate the thermal output of a nuclear reactor play a particularly important role in monitoring its operational status. Conventionally, control rod position indication in pressurized water reactors has been of the analog type, utilizing the principle of the differential transformer. The present digital system was developed with the objective of achieving greater stability, greater accuracy, and higher reliability. The article gives a general description of the system and describes its advantages. (author)

Positioning drive for absorber rods of a nuclear reactor

International Nuclear Information System (INIS)

Acher, H.

1977-01-01

The invention concerns a positioning drive for absorber rods of a nuclear reactor, of a threaded spindle and traveling nut type. In this positioning drive, rollers are provided the nut, which engage with the threads of the spindle and have an axis extending essentially at right angles to the longitudinal axis of the spindle. Three of the rollers are preferably combined in a traveling-nut housing, by means of anti-friction bearing elements. The positioning speed of such mechanical spindle drives can be increased thereby substantially. The invention is of interest particularly for boiling-water reactors. 9 claims, 8 figures

Water quality effects of intermittent water supply in Arraiján, Panama.

Science.gov (United States)

Erickson, John J; Smith, Charlotte D; Goodridge, Amador; Nelson, Kara L

2017-05-01

Intermittent drinking water supply is common in low- and middle-income countries throughout the world and can cause water quality to degrade in the distribution system. In this study, we characterized water quality in one study zone with continuous supply and three zones with intermittent supply in the drinking water distribution network in Arraiján, Panama. Low or zero pressures occurred in all zones, and negative pressures occurred in the continuous zone and two of the intermittent zones. Despite hydraulic conditions that created risks for backflow and contaminant intrusion, only four of 423 (0.9%) grab samples collected at random times were positive for total coliform bacteria and only one was positive for E. coli. Only nine of 496 (1.8%) samples had turbidity >1.0 NTU and all samples had ≥0.2 mg/L free chlorine residual. In contrast, water quality was often degraded during the first-flush period (when supply first returned after an outage). Still, routine and first-flush water quality under intermittent supply was much better in Arraiján than that reported in a previous study conducted in India. Better water quality in Arraiján could be due to better water quality leaving the treatment plant, shorter supply outages, higher supply pressures, a more consistent and higher chlorine residual, and fewer contaminant sources near pipes. The results illustrate that intermittent supply and its effects on water quality can vary greatly between and within distribution networks. The study also demonstrated that monitoring techniques designed specifically for intermittent supply, such as continuous pressure monitoring and sampling the first flush, can detect water quality threats and degradation that would not likely be detected with conventional monitoring. Copyright © 2017 Elsevier Ltd. All rights reserved.

Positive enteric contrast material for abdominal and pelvic CT with automatic exposure control: What is the effect on patient radiation exposure?

Energy Technology Data Exchange (ETDEWEB)

Wang, Zhen J., E-mail: jane.wang@radiology.ucsf.edu [Department of Radiology, University of California San Francisco, 505 Parnassus Avenue, San Francisco, CA 94143-0628 (United States); Chen, Katherine S.; Gould, Robert; Coakley, Fergus V.; Fu Yanjun; Yeh, Benjamin M. [Department of Radiology, University of California San Francisco, 505 Parnassus Avenue, San Francisco, CA 94143-0628 (United States)

2011-08-15

Objective: To assess the effect of positive enteric contrast administration on automatic exposure control (AEC) CT radiation exposure in (1) a CT phantom, and (2) a retrospective review of patients. Materials and methods: We scanned a CT phantom containing simulated bowel that was sequentially filled with water and positive enteric contrast, and recorded the mean volume CT dose index (CTDIvol). We also identified 17 patients who had undergone 2 technically comparable CT scans of the abdomen and pelvis, one with positive enteric contrast and the other with oral water. Paired Student's t-tests were used to compare the mean CTDIvol between scans performed with and without positive enteric contrast. Both the phantom and patient CT scans were performed using AEC with a fixed noise index. Results: The mean CTDIvol for the phantom with simulated bowel containing water and positive enteric contrast were 8.2 {+-} 0.2 mGy, and 8.7 {+-} 0.1 mGy (6.1% higher than water, p = 0.02), respectively. The mean CTDIvol for patients scanned with oral water and with positive enteric contrast were 11.8 mGy and 13.1 mGy, respectively (p = 0.003). This corresponded to a mean CTDIvol which was 11.0% higher (range: 0.0-20.7% higher) in scans with positive enteric contrast than those with oral water in patients. Conclusions: When automatic exposure control is utilized for abdominopelvic CT, the radiation exposure, as measured by CTDIvol, is higher for scans performed with positive enteric contrast than those with oral water.

Investigating the effects of tea, water and a positive affect induction on mood and creativity

NARCIS (Netherlands)

Einöther, S.J.L.; Baas, M.; Rowson, M.; Giesbrecht, T.

2015-01-01

Positive affect has been shown to be predictive of improved creativity. This study investigated the immediate effect of the tea experience on positive affect and creativity, compared to both a neutral and positive control condition. Regular tea drinkers (N = 150) were allocated to three conditions:

Strength, Endurance, Throwing Velocity and in-Water Jump Performance of Elite German Water Polo Players

Directory of Open Access Journals (Sweden)

Zinner Christoph

2015-03-01

Full Text Available The purpose of this study was threefold: 1 to assess the eggbeater kick and throwing performance using a number of water polo specific tests, 2 to explore the relation between the eggbeater kick and throwing performance, and 3 to investigate the relation between the eggbeater kick in the water and strength tests performed in a controlled laboratory setting in elite water polo players. Fifteen male water polo players of the German National Team completed dynamic and isometric strength tests for muscle groups (adductor, abductor, abdominal, pectoralis frequently used during water polo. After these laboratory strength tests, six water polo specific in-water tests were conducted. The eggbeater kick assessed leg endurance and agility, maximal throwing velocity and jump height. A 400 m test and a sprint test examined aerobic and anaerobic performance. The strongest correlation was found between jump height and arm length (p < 0.001, r = 0.89. The laboratory diagnostics of important muscles showed positive correlations with the results of the in-water tests (p < 0.05, r = 0.52-0.70. Muscular strength of the adductor, abdominal and pectoralis muscles was positively related to in-water endurance agility as assessed by the eggbeater kick (p < 0.05; r = 0.53-0.66. Findings from the current study emphasize the need to assess indices of water polo performance both in and out of the water as well as the relation among these parameters to best assess the complex profile of water polo players.

Cold neutron source with self-regulation

International Nuclear Information System (INIS)

Kawai, T.

2003-01-01

A way to increase the cold neutron flux is to cool moderator from where cold neutrons are extracted. Although various kinds of cooling system are considered, the closed thermo-siphon cooling system is adopted in many institutes. The notable feature of this system is to be able to keep the liquid level stable in the moderator cell against thermal disturbances, by using self-regulation, which allows a stable supply of cold neutrons. The main part of the closed thermo-siphon consists of a condenser, a moderator transfer tube and moderator cell, which is called the hydrogen cold system. When an extra heat load is applied to the hydrogen cold system having no flow resistance in a moderator transfer tube, the system pressure rises by evaporation of liquid hydrogen. Then the boiling point of hydrogen rises. The liquefaction capacity of the condenser is increasing with a rise of temperature, because a refrigerating power of the helium refrigerator increases linearly with temperature rise of the system. Therefore, the effect of thermal heat load increase is compensated and cancelled out. The closed thermo-siphon has this feature generally, when the moderator transfer tube is designed to be no flow resistance. The report reviews the concept of self-regulation, and how to design and construct the cold neutron source with self-regulation. (author)

Biofilm bacterial communities in urban drinking water distribution systems transporting waters with different purification strategies.

Science.gov (United States)

Wu, Huiting; Zhang, Jingxu; Mi, Zilong; Xie, Shuguang; Chen, Chao; Zhang, Xiaojian

2015-02-01

Biofilm formation in drinking water distribution systems (DWDS) has many adverse consequences. Knowledge of microbial community structure of DWDS biofilm can aid in the design of an effective control strategy. However, biofilm bacterial community in real DWDS and the impact of drinking water purification strategy remain unclear. The present study investigated the composition and diversity of biofilm bacterial community in real DWDSs transporting waters with different purification strategies (conventional treatment and integrated treatment). High-throughput Illumina MiSeq sequencing analysis illustrated a large shift in the diversity and structure of biofilm bacterial community in real DWDS. Proteobacteria, Firmicutes, Bacteroidetes, Actinobacteria, Nitrospirae, and Cyanobacteria were the major components of biofilm bacterial community. Proteobacteria (mainly Alphaproteobacteria, Betaproteobacteria, and Gammaproteobacteria) predominated in each DWDS biofilm, but the compositions of the dominant proteobacterial classes and genera and their proportions varied among biofilm samples. Drinking water purification strategy could shape DWDS biofilm bacterial community. Moreover, Pearson's correlation analysis indicated that Actinobacteria was positively correlated with the levels of total alkalinity and dissolved organic carbon in tap water, while Firmicutes had a significant positive correlation with nitrite nitrogen.

Social representations of drinking water: subsidies for water quality surveillance programmes.

Science.gov (United States)

Carmo, Rose Ferraz; Bevilacqua, Paula Dias; Barletto, Marisa

2015-09-01

A qualitative study was developed aimed at understanding the social representations of water consumption by a segment of the population of a small town in Brazil. A total of 19 semi-structured interviews were carried out and subjected to a content analysis addressing opinion on drinking water, characteristics of drinking water and its correlation to health and diseases, criteria for water usage and knowledge on the source and accountability for drinking-water quality. Social representations of drinking water predominantly incorporate the municipal water supply and sanitation provider and its quality. The identification of the municipal water supply provider as alone responsible for maintaining water quality indicated the lack of awareness of any health surveillance programme. For respondents, chlorine was accountable for conferring colour, odour and taste to the water. These physical parameters were reported as the cause for rejecting the water supplied and suggest the need to review the focus of health-educational strategies based on notions of hygiene and water-borne diseases. The study allowed the identification of elements that could contribute to positioning the consumers vs. services relationship on a level playing field, enabling dialogue and exchange of knowledge for the benefit of public health.

Benchmarking organic micropollutants in wastewater, recycled water and drinking water with in vitro bioassays.

Science.gov (United States)

Escher, Beate I; Allinson, Mayumi; Altenburger, Rolf; Bain, Peter A; Balaguer, Patrick; Busch, Wibke; Crago, Jordan; Denslow, Nancy D; Dopp, Elke; Hilscherova, Klara; Humpage, Andrew R; Kumar, Anu; Grimaldi, Marina; Jayasinghe, B Sumith; Jarosova, Barbora; Jia, Ai; Makarov, Sergei; Maruya, Keith A; Medvedev, Alex; Mehinto, Alvine C; Mendez, Jamie E; Poulsen, Anita; Prochazka, Erik; Richard, Jessica; Schifferli, Andrea; Schlenk, Daniel; Scholz, Stefan; Shiraishi, Fujio; Snyder, Shane; Su, Guanyong; Tang, Janet Y M; van der Burg, Bart; van der Linden, Sander C; Werner, Inge; Westerheide, Sandy D; Wong, Chris K C; Yang, Min; Yeung, Bonnie H Y; Zhang, Xiaowei; Leusch, Frederic D L

2014-01-01

Thousands of organic micropollutants and their transformation products occur in water. Although often present at low concentrations, individual compounds contribute to mixture effects. Cell-based bioassays that target health-relevant biological endpoints may therefore complement chemical analysis for water quality assessment. The objective of this study was to evaluate cell-based bioassays for their suitability to benchmark water quality and to assess efficacy of water treatment processes. The selected bioassays cover relevant steps in the toxicity pathways including induction of xenobiotic metabolism, specific and reactive modes of toxic action, activation of adaptive stress response pathways and system responses. Twenty laboratories applied 103 unique in vitro bioassays to a common set of 10 water samples collected in Australia, including wastewater treatment plant effluent, two types of recycled water (reverse osmosis and ozonation/activated carbon filtration), stormwater, surface water, and drinking water. Sixty-five bioassays (63%) showed positive results in at least one sample, typically in wastewater treatment plant effluent, and only five (5%) were positive in the control (ultrapure water). Each water type had a characteristic bioanalytical profile with particular groups of toxicity pathways either consistently responsive or not responsive across test systems. The most responsive health-relevant endpoints were related to xenobiotic metabolism (pregnane X and aryl hydrocarbon receptors), hormone-mediated modes of action (mainly related to the estrogen, glucocorticoid, and antiandrogen activities), reactive modes of action (genotoxicity) and adaptive stress response pathway (oxidative stress response). This study has demonstrated that selected cell-based bioassays are suitable to benchmark water quality and it is recommended to use a purpose-tailored panel of bioassays for routine monitoring.

Improving conveyance and distribution efficiency through conversion of an open channel lateral canal to a low pressure pipeline at Al-Hassa Irrigation Project, Saudi Arabia

International Nuclear Information System (INIS)

Aldakheel, Y.; Zeineldin, F.

2007-01-01

This paper describes a field case study on the use of a semi-buried poly-vinyl chloride (PVC) pipeline system in Al-Hassa oasis, Saudi Arabia and its contribution in improving water conservation. Deteriorated concrete canals at Al-Hassa irrigation project, enhanced irrigation water losses, and the annual cost of maintenance became uneconomical for the long term. The PVC pipes easy maintenance, durability, modification and flexibility give them the potential to be an economical alternative to replace a concrete lateral canal, P1H4, at Al-Hassa irrigation project. Due to the availability of PVC pipes at low cost in the Kingdom and their common use in irrigation, they were selected to construct a pipeline, 362 m in length. An energy head, 2.7 m of water, was used in determining the pipeline capacity and its internal diameter, using the continuity equation. Dismantling of the concrete canal and installing of the pipeline took place simultaneously without water stresses to the grown crops. The conveyance and distribution efficiencies increased by 25.3% and 25% respectively due to installation of pipeline. The water use with illegal extra siphons was reduced by 29.2% under the pipeline system. (author)

PH measurement under pressure and at high temperatures; Mesure du pH sous pression et a temperature elevee

Energy Technology Data Exchange (ETDEWEB)

Fournie, R [Commissariat a l' Energie Atomique, Saclay (France). Centre d' Etudes Nucleaires; Le Peintre, M; Mahieu, C [Centre National de la Recherche Scientifique (CNRS), 91 - Gif-sur-Yvette (France)

1961-07-01

In the first part the development and operation of a glass electrode under pressure at room temperature is described. The pressure equilibrium between the inside and outside of the glass membrane several centimetres thick is obtained instantaneously by means of a siphon. The use of a silicone oil as electrical insulator makes possible the working of the glass electrode with the siphon at high pressures (100 kg/cm{sup 2}). In the second part, we determined the pH of various buffer solutions up to 250 deg. C using a cell of our design having two hydrogen electrodes. The values thus obtained for the buffer solutions make it possible to verify and calibrate the pH electrodes independently of the oxido-reduction potential of the medium. In the third part we give the results obtained up to 200 deg. C with the glass electrodes developed in conjunction with the Societe St Gobain. (author) [French] Dans une premiere partie, nous exposons la mise au point et le fonctionnement d'une electrode en verre sous pression a la temperature ordinaire. L'equilibrage instantane de la pression a l'interieur et a l'exterieur de la membrane en verre de quelques diziemes de millimetres d'epaisseur s'effectue par l'intermediaire d'un siphon. L'emploi d'une huile de silicone comme isolant electrique a permis le fonctionnement de l'electrode en verre a siphon sous haute pression (1000 kg/cm{sup 2}). Dans une deuxieme partie, nous avons determine jusqu'a 250 deg. C les valeurs du pH des diverses solutions tampons avec une cellule de notre conception a deux electrodes d'hydrogene. Les valeurs des solutions tampons ainsi obtenues permettent de verifier et d'etalonner les electrodes a pH independantes du potentiel d'oxydo-reduction du milieu. Dans une troisieme partie, nous relatons les resultats obtenus jusqu'a 200 deg. C avec les electrodes en verre mis au point en collaboration avec la Societe Saint-Gobain. (auteur)

Prevailence of Patch Test Positivity with Some Bases

Directory of Open Access Journals (Sweden)

J S Pasricha

1987-01-01

Full Text Available To evaluate the suitability of some chemicals to act as bases for antigens for patch tests, patch tests were performed with these agents in patients having contact dermatitis. Propylene glycol′used as such produced positive reactions in 25 (50% patients of which 12 were 2 + or more, polyethylene glycol 200 produced positive reactions in 9 (18% cases of which 4 cases were 2 + or more, a mixture of liquid paraffin and hard paraffin gave rise to positive reactions in 10 (10% cases 3 of these being 2 +, a mixture of liquid paraffin and bees wax was positive in 14 (14,Yo cases 3 of these being 2 +, yellow petrolatum was positive in 4 (8% cases, one of which was 2 +, white petrolatum was positive in S (6% cases all of these being + reactions only, and glycerol gave rise to a I + reaction in only one (2% caw. In tropical countries, water should be as base for as many antigens as possible for others, a control test with the b must be included.

On the development of inexpensive speed and position tracking system for swimming

DEFF Research Database (Denmark)

Trangbæk, Søren; Rasmussen, Cuno; Andersen, Thomas Bull

2016-01-01

A semi-automated tracking system was developed for the analysis of swimming, using cameras, an LED diode marker, and a red swim cap. Four experienced young swimmers were equipped with a marker and a swim cap and their position and speed was tracked throughout above-water and under-water swimming...

Research Article Special Issue

African Journals Online (AJOL)

pc

2018-02-01

Feb 1, 2018 ... current control [2, 3] and about regulation of the production situation as well ... measuring instruments, and the process parameters of the transport system ... instrumentation malfunction, leakage or unauthorized siphoning of ...

Home Parenteral Nutrition (HPN) Complication Chart

Science.gov (United States)

... Chest pain; coughing; shortness of breath; loss of consciousness. Air siphoned into catheter due to IV tubing ... with the use of long term central venous access devices for HPN. To protect your access, always ...

Characteristics of water infiltration in layered water repellent soils

Science.gov (United States)

Hydrophobic soil can influence soil water infiltration, but information regarding the impacts of different levels of hydrophobicity within a layered soil profile is limited. An infiltration study was conducted to determine the effects of different levels of hydrophobicity and the position of the hyd...

A floating water bridge produces water with excess charge

Science.gov (United States)

Fuchs, Elmar C.; Sammer, Martina; Wexler, Adam D.; Kuntke, Philipp; Woisetschläger, Jakob

2016-03-01

Excess positive and negative Bjerrum-defect like charge (protonic and ‘aterprotonic’, from ancient Greek ἄ'τɛρ, ‘without’) in anolyte and catholyte of high voltage electrolysis of highly pure water was found during the so-called ‘floating water bridge’ experiment. The floating water bridge is a special case of an electrohydrodynamic liquid bridge and constitutes an intriguing phenomenon that occurs when a high potential difference (~kV cm-1) is applied between two beakers of water. To obtain such results impedance spectroscopy was used. This measurement technique allows the depiction and simulation of complex aqueous systems as simple electric circuits. In the present work we show that there is an additional small contribution from the difference in conductivity between anolyte and catholyte which cannot be measured with a conductivity meter, but is clearly visible in an impedance spectrum.

Analysis of Radiosonde Daily Bias by Comparing Precipitable Water Vapor Obtained from Global Positioning System and Radiosonde

Directory of Open Access Journals (Sweden)

Chang-Geun Park

2010-12-01

Full Text Available In this study, we compared the precipitable water vapor (PWV data derived from the radiosonde observation data at Sokcho Observatory and the PWV data at Sokcho Global Positioning System (GPS Observatory provided by Korea Astronomy and Space Science Institute, from 0000 UTC, June 1, 2007 to 1200 UTC, May 31, 2009, and analyzed the radiosonde bias between the day and the night. In the scatter diagram of the daytime and nighttime radiosonde PWV data and the GPS PWV data, dry bias was found in the daytime radiosonde observation as known in the previous study. In addition, for all the rainfall events, the tendency that the wet bias of the radiosonde PWV increased as the GPS PWV decreased and the dry bias of the radiosonde PWV increased as the GPS PWV increased was significantly less distinctive in nighttime than in daytime. The quantitative analysis of the bias and error of the radiosonde PWV data showed that the mean bias decreased in the second year, regardless of nighttime or daytime rainfall, and the non-rainfall root mean square error (RMSE was similar to that of the previous studies, while the rainfall RMSE was larger to a certain extent.

Hydrokinesitherapy in thermal mineral water

Directory of Open Access Journals (Sweden)

Rendulić-Slivar Senka

2013-01-01

Full Text Available The treatment of clients in health spa resorts entails various forms of hydrotherapy. Due to specific properties of water, especially thermal mineral waters, hydrokinesitherapy has a positive effect on the locomotor system, aerobic capabilities of organism and overall quality of human life. The effects of use of water in movement therapy are related to the physical and chemical properties of water. The application of hydrotherapy entails precautionary measures, with an individual approach in assessment and prescription. The benefits of treatment in thermal mineral water should be emphasized and protected, as all thermal mineral waters differ in composition. All physical properties of water are more pronounced in thermal mineral waters due to its mineralisation, hence its therapeutical efficiency is greater, as well.

Coarse-Grained Model for Water Involving a Virtual Site.

Science.gov (United States)

Deng, Mingsen; Shen, Hujun

2016-02-04

In this work, we propose a new coarse-grained (CG) model for water by combining the features of two popular CG water models (BMW and MARTINI models) as well as by adopting a topology similar to that of the TIP4P water model. In this CG model, a CG unit, representing four real water molecules, consists of a virtual site, two positively charged particles, and a van der Waals (vdW) interaction center. Distance constraint is applied to the bonds formed between the vdW interaction center and the positively charged particles. The virtual site, which carries a negative charge, is determined by the locations of the two positively charged particles and the vdW interaction center. For the new CG model of water, we coined the name "CAVS" (charge is attached to a virtual site) due to the involvment of the virtual site. After being tested in molecular dynamic (MD) simulations of bulk water at various time steps, under different temperatures and in different salt (NaCl) concentrations, the CAVS model offers encouraging predictions for some bulk properties of water (such as density, dielectric constant, etc.) when compared to experimental ones.

Assessing Drinking Water Quality and Water Safety Management in Sub-Saharan Africa Using Regulated Monitoring Data.

Science.gov (United States)

Kumpel, Emily; Peletz, Rachel; Bonham, Mateyo; Khush, Ranjiv

2016-10-18

Universal access to safe drinking water is prioritized in the post-2015 Sustainable Development Goals. Collecting reliable and actionable water quality information in low-resource settings, however, is challenging, and little is known about the correspondence between water quality data collected by local monitoring agencies and global frameworks for water safety. Using 42 926 microbial water quality test results from 32 surveillance agencies and water suppliers in seven sub-Saharan African countries, we determined the degree to which water sources were monitored, how water quality varied by source type, and institutional responses to results. Sixty-four percent of the water samples were collected from piped supplies, although the majority of Africans rely on nonpiped sources. Piped supplies had the lowest levels of fecal indicator bacteria (FIB) compared to any other source type: only 4% of samples of water piped to plots and 2% of samples from water piped to public taps/standpipes were positive for FIB (n = 14 948 and n = 12 278, respectively). Among other types of improved sources, samples from harvested rainwater and boreholes were less often positive for FIB (22%, n = 167 and 31%, n = 3329, respectively) than protected springs or protected dug wells (39%, n = 472 and 65%, n = 505). When data from different settings were aggregated, the FIB levels in different source types broadly reflected the source-type water safety framework used by the Joint Monitoring Programme. However, the insufficient testing of nonpiped sources relative to their use indicates important gaps in current assessments. Our results emphasize the importance of local data collection for water safety management and measurement of progress toward universal safe drinking water access.

Genome sequence of a urease-positive Campylobacter lari strain

Science.gov (United States)

Campylobacter lari is frequently isolated from shore birds and can cause illness in humans. Here we report the draft whole genome sequence of an urease-positive strain of C. lari that was isolated in estuarial water on the coast of Delaware, USA....

77 FR 107 - Notice of Preliminary Permit Application Accepted for Filing and Soliciting Comments, Motions To...

Science.gov (United States)

2012-01-03

... underground weholite pipe and an 845-foot-long, 72-inch-diameter underground steel pipe; (3) two Kaplan turbines totaling 2.03 megawatts; (4) a 10-foot-long, 14-foot-wide concrete powerhouse; (5) two siphon...

CNE (Embalse nuclear power plant): probabilistic safety study. Electric power supply. Events sequence

International Nuclear Information System (INIS)

Figueroa, N.

1987-01-01

The plant response to the occurrence of the starting event 'total loss of electric power supply to class IV and class III' is analyzed. This involves the study of automatical actions of safety and process systems as well as the operator actions. The probabilistic evaluation of starting event frequency is performed through fault-tree techniques. The frequency of occurrence 'loss of electric power supply to class IV (λIV = 0.56/year) and the probability of failure to demand of 'reserve' generating groups (Pd III 6.79 x 10 -3 ) contribute to the mentioned frequency. As soon as the starting event occurs, the reactor power must be reduced to 0%, the fuel must be cooled through the thermo siphon and decay heat has to be removed. The events sequence analysis leads to the conclusion that the non shutting down of the reactor with any of the shutdown systems is 'incredible' (10 -6 /year). In all cases the fuel is cooled by building the thermo siphon except when a substantial inventory loss exist due to a closure failure of some valve of pressure and inventory control system. The order of magnitude of the failure of decay heat removal through the steam generators is 4 x 10 -4 . This removal would be assured by the emergency water system. Therefore, the frequency of the sequence of possible core meltdown, when the reactor does not shut down is: λ = 5 x 10 -9 /year and for the failure of heat removal: λ = 2 x 10 -6 /year. (Author)

Frequency of HEV contamination in sewerage waters in Pakistan.

Science.gov (United States)

Ahmad, Tahir; Waheed, Yasir; Tahir, Sadia; Safi, Sher Zaman; Fatima, Kaneez; Afzal, Muhammad Sohail; Farooqi, Zia-ur-Rehman; Qadri, Ishtiaq

2010-12-23

Enteric viruses, including Hepatitis E virus (HEV), are able to persist under environmental conditions and may cause public health problems by contaminating natural and drinking water resources. Routine procedures for monitoring viruses in water samples have not been established for the water microbiology screening panel. Eighty-six raw sewerage samples were collected from the different regions of Islamabad and Rawalpindi, the twin cities of Pakistan. Samples were concentrated for HEV, using a polyethylene glycol-based method followed by viral RNA extraction using a commercial kit-based method. Reverse transcription polymerase chain reaction (RT-PCR) with HEV specific primers was used for the detection of HEV. The present investigation focused on 86 raw sewerage water samples taken from different locations of drainage outlets of Islamabad and Rawalpindi. After careful experimentation, 35 samples were found to be RT-PCR positive.  Nineteen (44.7%) out of 47 samples from Rawalpindi city were HEV positive while 16 (41.02%) out of 39 samples from Islamabad were HEV positive. All positive samples were found in the highly congested areas. The high detection rate of HEV in this study shows that HEV circulates at a relatively high frequency in the sewerage waters in Pakistan. This study is the first report on detection of HEV from sewerage waste water from Pakistan and suggests that HEV might be a potent indicator of viral pollution in environmental specimens.

Soils and water [Chapter 18

Science.gov (United States)

Goran Berndes; Heather Youngs; Maria Victoria Ramos Ballester; Heitor Cantarella; Annette L. Cowie; Graham Jewitt; Luiz Antonio Martinelli; Dan Neary

2015-01-01

Bioenergy production can have positive or negative impacts on soil and water. To best understand these impacts, the effects of bioenergy systems on water and soil resources should be assessed as part of an integrated analysis considering environmental, social and economic dimensions. Bioenergy production systems that are strategically integrated in the landscape to...

Accurate ocean bottom seismometer positioning method inspired by multilateration technique

Science.gov (United States)

Benazzouz, Omar; Pinheiro, Luis M.; Matias, Luis M. A.; Afilhado, Alexandra; Herold, Daniel; Haines, Seth S.

2018-01-01

The positioning of ocean bottom seismometers (OBS) is a key step in the processing flow of OBS data, especially in the case of self popup types of OBS instruments. The use of first arrivals from airgun shots, rather than relying on the acoustic transponders mounted in the OBS, is becoming a trend and generally leads to more accurate positioning due to the statistics from a large number of shots. In this paper, a linearization of the OBS positioning problem via the multilateration technique is discussed. The discussed linear solution solves jointly for the average water layer velocity and the OBS position using only shot locations and first arrival times as input data.

A sub-tank water-saving drinking water station

Science.gov (United States)

Zhang, Ting

2017-05-01

"Thousands of boiling water" problem has been affecting people's quality of life and good health, and now most of the drinking fountains cannot effectively solve this problem, at the same time, ordinary drinking water also has high energy consumption, there are problems such as yin and yang water. Our newly designed dispenser uses a two-tank heating system. Hot water after heating, into the insulation tank for insulation, when the water tank in the water tank below a certain water level, the cold water and then enter the heating tank heating. Through the water flow, tank volume and other data to calculate the time required for each out of water, so as to determine the best position of the water level control, summed up the optimal program, so that water can be continuously uninterrupted supply. Two cans are placed up and down the way, in the same capacity on the basis of the capacity of the container, the appropriate to reduce its size, and increase the bottom radius, reduce the height of its single tank to ensure that the overall height of two cans compared with the traditional single change. Double anti-dry design, to ensure the safety of the use of drinking water. Heating tank heating circuit on and off by the tank of the float switch control, so that the water heating time from the tank water level control, to avoid the "thousands of boiling water" generation. The entry of cold water is controlled by two solenoid valves in the inlet pipe, and the opening and closing of the solenoid valve is controlled by the float switch in the two tanks. That is, the entry of cold water is determined by the water level of the two tanks. By designing the control scheme cleverly, Yin and yang water generation. Our design completely put an end to the "thousands of boiling water", yin and yang water, greatly improving the drinking water quality, for people's drinking water safety provides a guarantee, in line with the concept of green and healthy development. And in the small

A floating water bridge produces water with excess charge

International Nuclear Information System (INIS)

Fuchs, Elmar C; Sammer, Martina; Wexler, Adam D; Kuntke, Philipp; Woisetschläger, Jakob

2016-01-01

Excess positive and negative Bjerrum-defect like charge (protonic and ‘aterprotonic’, from ancient Greek ατερ, ‘without’) in anolyte and catholyte of high voltage electrolysis of highly pure water was found during the so-called ‘floating water bridge’ experiment. The floating water bridge is a special case of an electrohydrodynamic liquid bridge and constitutes an intriguing phenomenon that occurs when a high potential difference (∼kV cm −1 ) is applied between two beakers of water. To obtain such results impedance spectroscopy was used. This measurement technique allows the depiction and simulation of complex aqueous systems as simple electric circuits. In the present work we show that there is an additional small contribution from the difference in conductivity between anolyte and catholyte which cannot be measured with a conductivity meter, but is clearly visible in an impedance spectrum. (paper)

Water management in Germany

International Nuclear Information System (INIS)

Teuber, W.; Bosenius, U.; Henke, J.

1994-03-01

The report was drawn up for the US day on water pollution prevention on 22 March 1994, as a follow-up to the 1992 Rio de Janairo conference on the environment and development, and presented to the International Water Conference in Noordwijk, the Netherlands. It gives a current overview of the foundations and structure, the development, position and points of emphasis for the german water industry. The report illustrates the extent of the success of german measures towards resolving it's water pollution problems, in particular the reduction of contamination. It clarifies the great challenges facing the german water industry in the Nineties, and hence illustrates more long-term goals - which will only be achieved through greater international cooperation. (orig./HP) [de

Water Reserves Program. An adaptation strategy to balance water in nature

Science.gov (United States)

Lopez Perez, M.; Barrios, E.; Salinas-Rodriguez, S.; Wickel, B.; Villon, R. A.

2013-05-01

Freshwater ecosystems occupy approximately 1% of the earth's surface yet possess about 12% of all known animal species. By virtue of their position in the landscape they connect terrestrial and coastal marine biomes and provide and sustain ecosystem services vital to the health and persistence of human communities. These services include the supply of water for food production, urban and ind ustrial consumption, among others. Over the past century many freshwater ecosystems around the world have been heavily modified or lost due to the alteration of flow regimes (e.g. due to damming, canalization, diversion, over-abstraction). The synergistic impacts of land use change, changes in flows, chemical deterioration, and climate change have left many systems and their species very little room to adjust to change, while future projections indicate a steady increase in water demand for food and energy production and water supply to suit the needs of a growing world population. In Mexico, the focus has been to secure water for human development and maximize economic growth, which has resulted in allocation of water beyond available amounts. As a consequence episodic water scarcity severely constrains freshwater ecosystems and the services they provide. Climatic change and variability are presenting serious challenges to a country that already is experiencing serious strain on its water resources. However, freshwater ecosystems are recognized by law as legitimate user of water, and mandate a flow allocation for the environment ("water reserve" or "environmental flows"). Based on this legal provision the Mexican government through the National Water Commission (Conagua), with support of the Alliance WWF - Fundación Gonzalo Río Arronte, and the Interamerican Development Bank, has launched a national program to identify and implement "water reserves": basins where environmental flows will be secured and allocated and where the flow regime is then protected before over

Patient position alters attenuation effects in multipinhole cardiac SPECT.

Science.gov (United States)

Timmins, Rachel; Ruddy, Terrence D; Wells, R Glenn

2015-03-01

Dedicated cardiac cameras offer improved sensitivity over conventional SPECT cameras. Sensitivity gains are obtained by large numbers of detectors and novel collimator arrangements such as an array of multiple pinholes that focus on the heart. Pinholes lead to variable amounts of attenuation as a source is moved within the camera field of view. This study evaluated the effects of this variable attenuation on myocardial SPECT images. Computer simulations were performed for a set of nine point sources distributed in the left ventricular wall (LV). Sources were placed at the location of the heart in both an anthropomorphic and a water-cylinder computer phantom. Sources were translated in x, y, and z by up to 5 cm from the center. Projections were simulated with and without attenuation and the changes in attenuation were compared. A LV with an inferior wall defect was also simulated in both phantoms over the same range of positions. Real camera data were acquired on a Discovery NM530c camera (GE Healthcare, Haifa, Israel) for five min in list-mode using an anthropomorphic phantom (DataSpectrum, Durham, NC) with 100 MBq of Tc-99m in the LV. Images were taken over the same range of positions as the simulations and were compared based on the summed perfusion score (SPS), defect width, and apparent defect uptake for each position. Point sources in the water phantom showed absolute changes in attenuation of ≤8% over the range of positions and relative changes of ≤5% compared to the apex. In the anthropomorphic computer simulations, absolute change increased to 20%. The changes in relative attenuation caused a change in SPS of position-dependent changes were removed with attenuation correction. Translation of a source relative to a multipinhole camera caused only small changes in homogeneous phantoms with SPS changing position-dependent changes in attenuation.

Ribeira do Iguape basin water quality assessment for drinking water supply

International Nuclear Information System (INIS)

Cotrim, Marycel Elena Barboza

2006-01-01

Ribeira do Iguape Basin, located in the Southeast region of Sao Paulo state, is the largest remaining area of Mata Atlantica which biodiversity as rich as Amazon forest , where the readiness of water versus demand is extremely positive. With sparse population density and economy almost dependent on banana agriculture, the region is still well preserved. To water supply SABESP (Sao Paulo State Basic Sanitation Company). Ribeira do Iguape Businesses Unit - RR, uses different types of water supplies. In the present work, in order to ascertain water quality for human consumption, major and minor elements were evaluated in various types of water supply (surface and groundwater's as well as the drinking water supplied). Forty three producing systems were monitored: 18 points of surface waters and treated distributed water, 10 points of groundwater and 15 points of surface water in preserved areas, analyzing 30 elements. Bottom sediments (fraction -1 and 172 μg.g -1 , respectively. Data revealed that trace elements concentration in the sediment were below PEL (Probable Effect Level - probable level of adverse effect to the biological community), exception for Pb in Sete Barras and Eldorado. (author)

Patient position alters attenuation effects in multipinhole cardiac SPECT

International Nuclear Information System (INIS)

Timmins, Rachel; Ruddy, Terrence D.; Wells, R. Glenn

2015-01-01

Purpose: Dedicated cardiac cameras offer improved sensitivity over conventional SPECT cameras. Sensitivity gains are obtained by large numbers of detectors and novel collimator arrangements such as an array of multiple pinholes that focus on the heart. Pinholes lead to variable amounts of attenuation as a source is moved within the camera field of view. This study evaluated the effects of this variable attenuation on myocardial SPECT images. Methods: Computer simulations were performed for a set of nine point sources distributed in the left ventricular wall (LV). Sources were placed at the location of the heart in both an anthropomorphic and a water-cylinder computer phantom. Sources were translated in x, y, and z by up to 5 cm from the center. Projections were simulated with and without attenuation and the changes in attenuation were compared. A LV with an inferior wall defect was also simulated in both phantoms over the same range of positions. Real camera data were acquired on a Discovery NM530c camera (GE Healthcare, Haifa, Israel) for five min in list-mode using an anthropomorphic phantom (DataSpectrum, Durham, NC) with 100 MBq of Tc-99m in the LV. Images were taken over the same range of positions as the simulations and were compared based on the summed perfusion score (SPS), defect width, and apparent defect uptake for each position. Results: Point sources in the water phantom showed absolute changes in attenuation of ≤8% over the range of positions and relative changes of ≤5% compared to the apex. In the anthropomorphic computer simulations, absolute change increased to 20%. The changes in relative attenuation caused a change in SPS of <1.5 for the water phantom but up to 4.2 in the anthropomorphic phantom. Changes were larger for axial than for transverse translations. These results were supported by SPS changes of up to six seen in the physical anthropomorphic phantom for axial translations. Defect width was also seen to significantly increase. The

Position detectors, methods of detecting position, and methods of providing positional detectors

Science.gov (United States)

Weinberg, David M.; Harding, L. Dean; Larsen, Eric D.

2002-01-01

Position detectors, welding system position detectors, methods of detecting various positions, and methods of providing position detectors are described. In one embodiment, a welding system positional detector includes a base that is configured to engage and be moved along a curved surface of a welding work piece. At least one position detection apparatus is provided and is connected with the base and configured to measure angular position of the detector relative to a reference vector. In another embodiment, a welding system positional detector includes a weld head and at least one inclinometer mounted on the weld head. The one inclinometer is configured to develop positional data relative to a reference vector and the position of the weld head on a non-planar weldable work piece.

Emergy evaluation of water utilization benefits in water-ecological-economic system based on water cycle process

Science.gov (United States)

Guo, X.; Wu, Z.; Lv, C.

2017-12-01

The water utilization benefits are formed by the material flow, energy flow, information flow and value stream in the whole water cycle process, and reflected along with the material circulation of inner system. But most of traditional water utilization benefits evaluation are based on the macro level, only consider the whole material input and output and energy conversion relation, and lack the characterization of water utilization benefits accompanying with water cycle process from the formation mechanism. In addition, most studies are from the perspective of economics, only pay attention to the whole economic output and sewage treatment economic investment, but neglect the ecological function benefits of water cycle, Therefore, from the perspective of internal material circulation in the whole system, taking water cycle process as the process of material circulation and energy flow, the circulation and flow process of water and other ecological environment, social economic elements were described, and the composition of water utilization positive and negative benefits in water-ecological-economic system was explored, and the performance of each benefit was analyzed. On this basis, the emergy calculation method of each benefit was proposed by emergy quantitative analysis technique, which can realize the unified measurement and evaluation of water utilization benefits in water-ecological-economic system. Then, taking Zhengzhou city as an example, the corresponding benefits of different water cycle links were calculated quantitatively by emergy method, and the results showed that the emergy evaluation method of water utilization benefits can unify the ecosystem and the economic system, achieve uniform quantitative analysis, and measure the true value of natural resources and human economic activities comprehensively.

Detection and identification of enteroviruses from various drinking water sources in Taiwan

Science.gov (United States)

Hsu, Bing-Mu; Chen, Chien-Hsien; Wan, Min-Tao; Chang, Po-Jen; Fan, Cheng-Wei

2009-02-01

SummaryTwenty-three water samples, including seventeen from surface water reservoirs, three from the raw water of groundwater treatment plants, and three from small water systems, were collected in Taiwan and investigated for the presence of, as well as the species of enteroviruses. RT-PCR was used for the detection of enteroviruses. Results revealed that 23.5% of raw water samples from reservoirs were positive for enteroviruses. In addition, one of the three groundwater samples and two of the three small system water samples were positive for enteroviruses. Water samples that were positive for enteroviruses subsequently were evaluated by real-time PCR. The results indicated that enterovirus concentration in groundwater was lower than that in samples obtained from surface water sources. Enteroviruses were identified by nucleic acid sequencing in the 5'-untranslated regions. Three clusters of enteroviruses were identified as coxsackievirus A2, coxsackievirus A6, and enterovirus 71. The presence of enteroviruses indicates the possibility of waterborne transmission of enteroviruses in Taiwan, if water is not adequately treated.

Numerical analysis of transient pressure variation in the condenser of a nuclear power station

Energy Technology Data Exchange (ETDEWEB)

Wang, Xinjun; Zhou, Zijie; Song, Zhao [Xi' an Jiaotong University, Xi' an (China); Lu, Qiankui; Li, Jiafu [Dong Fang Turbine Co., Ltd, Deyang (China)

2016-02-15

To research the characteristics of the transient variation of pressure in a nuclear power station condenser under accident condition, a mathematical model was established which simulated the cycling cooling water, heat transfer and pressure in the condenser. The calculation program of transient variation characteristics was established in Fortran language. The pump's parameter, cooling line's organization, check valve's feature and the parameter of siphonic water-collecting well are involved in the cooling water flow's mathematical model. The initial conditions of control volume are determined by the steady state of the condenser. The transient characteristics of a 1000 MW nuclear power station's condenser and cooling water system were examined. The results show that at the condition of plant-power suspension of pump, the cooling water flow rate decreases rapidly and refluxes, then fluctuates to 0. The variation of heat transfer coefficient in the condenser has three stages: at start it decreases sharply, then increases and decreases, and keeps constant in the end. Under three conditions (design, water and summer), the condenser pressure goes up in fluctuation. The time intervals between condenser's pressure signals under three conditions are about 26.4 s, which can fulfill the requirement for safe operation of nuclear power station.

Accuracy improvement in the TDR-based localization of water leaks

Directory of Open Access Journals (Sweden)

Andrea Cataldo

Full Text Available A time domain reflectometry (TDR-based system for the localization of water leaks has been recently developed by the authors. This system, which employs wire-like sensing elements to be installed along the underground pipes, has proven immune to the limitations that affect the traditional, acoustic leak-detection systems.Starting from the positive results obtained thus far, in this work, an improvement of this TDR-based system is proposed. More specifically, the possibility of employing a low-cost, water-absorbing sponge to be placed around the sensing element for enhancing the accuracy in the localization of the leak is addressed.To this purpose, laboratory experiments were carried out mimicking a water leakage condition, and two sensing elements (one embedded in a sponge and one without sponge were comparatively used to identify the position of the leak through TDR measurements. Results showed that, thanks to the water retention capability of the sponge (which maintains the leaked water more localized, the sensing element embedded in the sponge leads to a higher accuracy in the evaluation of the position of the leak. Keywords: Leak localization, TDR, Time domain reflectometry, Water leaks, Underground water pipes

Windmills in Danish waters - an investigation of the visual effects related to the positioning of wind turbines on the sea bed

International Nuclear Information System (INIS)

1994-12-01

Investigations have shown that the visual consequences of setting up wind turbines on the sea bed are much greater than those following location on the land. One option is to locate them so far out to sea that they can hardly be seen from the coast but the investigation showed that it is impossible to place them anywhere in Danish coastal waters where they would be out of view from the land. Although it should be possible to locate windmills in coastal waters in such a way that it could be aesthetically acceptable, it is feared that local attitudes could be tentative. The general conditions of significance for evaluating the aesthetic effects of locating wind turbines at sea are described and the main principles of regional planning in coastal areas are explained in addition to the potentials for being able to judge the visual consequences from a viewpoint that is placed out at sea. Various examples of marine positionings of wind turbines at different distances from the coastline are described and evaluated. It is asserted that some Danish marine locations for wind turbines can be found that will have only limited visual consequences. Some of these are near to the coast and a considerable number of wind turbines could be placed there. The document is illustrated with large coloured photographs and maps of Danish coastal areas. (AB)

Development of a robust method for isolation of shiga toxin-positive Escherichia coli (STEC from fecal, plant, soil and water samples from a leafy greens production region in California.

Directory of Open Access Journals (Sweden)

Michael B Cooley

Full Text Available During a 2.5-year survey of 33 farms and ranches in a major leafy greens production region in California, 13,650 produce, soil, livestock, wildlife, and water samples were tested for Shiga toxin (stx-producing Escherichia coli (STEC. Overall, 357 and 1,912 samples were positive for E. coli O157:H7 (2.6% or non-O157 STEC (14.0%, respectively. Isolates differentiated by O-typing ELISA and multilocus variable number tandem repeat analysis (MLVA resulted in 697 O157:H7 and 3,256 non-O157 STEC isolates saved for further analysis. Cattle (7.1%, feral swine (4.7%, sediment (4.4%, and water (3.3% samples were positive for E. coli O157:H7; 7/32 birds, 2/145 coyotes, 3/88 samples from elk also were positive. Non-O157 STEC were at approximately 5-fold higher incidence compared to O157 STEC: cattle (37.9%, feral swine (21.4%, birds (2.4%, small mammals (3.5%, deer or elk (8.3%, water (14.0%, sediment (12.3%, produce (0.3% and soil adjacent to produce (0.6%. stx1, stx2 and stx1/stx2 genes were detected in 63%, 74% and 35% of STEC isolates, respectively. Subtilase, intimin and hemolysin genes were present in 28%, 25% and 79% of non-O157 STEC, respectively; 23% were of the "Top 6″ O-types. The initial method was modified twice during the study revealing evidence of culture bias based on differences in virulence and O-antigen profiles. MLVA typing revealed a diverse collection of O157 and non-O157 STEC strains isolated from multiple locations and sources and O157 STEC strains matching outbreak strains. These results emphasize the importance of multiple approaches for isolation of non-O157 STEC, that livestock and wildlife are common sources of potentially virulent STEC, and evidence of STEC persistence and movement in a leafy greens production environment.

MDEP Common Position CP-EPRWG-03. Common position on EPR containment mixing

International Nuclear Information System (INIS)

2015-01-01

The EPR containment is a new design, different from many typical pressurised water reactor (PWR) containments in that it uses a two room design concept. Equipment rooms immediately surrounding the reactor coolant system (RCS) are isolated from the rest of the containment. Beyond this inner region, personnel access can be provided during certain maintenance tasks. Separation is provided by structures and closed portals to minimise radiation exposure in the accessible space areas. During power operation, the inaccessible areas inside containment experience higher temperatures and radiation than the accessible areas. The EPR design includes a number of features that promotes mixing. Heat transfer to the containment heat sinks is promoted by the CONVECT system. The CONVECT system consists of rupture foils, convection foils, mixing dampers, and related instrumentation and control equipment. Rupture foils and convection foils are placed in the ceiling of each steam generator compartment. More than half of the foils are convection foils. The mixing dampers are located in the lower part of the containment in the in-containment refuelling water storage tank wall above the water level. There are eight of these. Opening of the foils and dampers is designed to set up circulation patterns in both the accessible and inaccessible areas. The rupture foils are passive components which will burst open if the pressure differential on the foils exceeds a predetermined value. The rupture foils burst in either direction. The convection foils which are passive components, are rupture foils placed in a frame. The frame is kept in the closed position by a fusible link. Should temperature rise to a set level, the link will melt with a short delay, and the frame will swing open by gravity. The result is that a convection foil will open on a pressure differential and will also open if the compartment temperature reaches a certain level. The mixing dampers open either on a differential

Safety assessment of greenhouse hydroponic tomatoes irrigated with reclaimed and surface water.

Science.gov (United States)

Lopez-Galvez, Francisco; Allende, Ana; Pedrero-Salcedo, Francisco; Alarcon, Juan Jose; Gil, Maria Isabel

2014-11-17

The impact of reclaimed and surface water on the microbiological safety of hydroponic tomatoes was assessed. Greenhouse tomatoes were irrigated with reclaimed and surface water and grown on two hydroponic substrates (coconut fiber and rock wool). Water samples (n=208) were taken from irrigation water, with and without the addition of fertilizers and drainage water, and hydroponic tomatoes (n=72). Samples were analyzed for indicator microorganisms, generic Escherichia coli and Listeria spp., and pathogenic bacteria such as Salmonella spp. and Shiga-toxigenic E. coli (STEC), using multiplex real-time PCR (RT-PCR) after enrichment. The correlation between climatological parameters such as temperature and the levels of microorganisms in water samples was also determined. In irrigation water, generic E. coli counts were higher in reclaimed than in surface water whereas Listeria spp. numbers increased after adding the fertilizers in both water sources. In drainage water, no clear differences in E. coli and Listeria numbers were observed between reclaimed and surface water. No positive samples for STEC were found in irrigation water. Presumptive positives for Salmonella spp. were found in 7.7% of the water samples and 62.5% of these samples were reclaimed water. Salmonella-positive samples by RT-PCR could not be confirmed by conventional methods. Higher concentrations of E. coli were associated with Salmonella-presumptive positive samples. Climatological parameters, such as temperature, were not correlated with the E. coli and Listeria spp. counts. Tomato samples were negative for bacterial pathogens, while generic E. coli and Listeria spp. counts were below the detection limit. The prevalence of presumptive Salmonella spp. found in irrigation water (reclaimed and surface water) was high, which might present a risk of contamination. The absence of pathogens on greenhouse hydroponic tomatoes indicates that good agricultural practices (GAP) were in place, avoiding the

Forward Model Studies of Water Vapor Using Scanning Microwave Radiometers, Global Positioning System, and Radiosondes during the Cloudiness Intercomparison Experiment

International Nuclear Information System (INIS)

Mattioli, Vinia; Westwater, Ed R.; Gutman, S.; Morris, Victor R.

2005-01-01

Brightness temperatures computed from five absorption models and radiosonde observations were analyzed by comparing them with measurements from three microwave radiometers at 23.8 and 31.4 GHz. Data were obtained during the Cloudiness Inter-Comparison experiment at the U.S. Department of Energy's Atmospheric Radiation Measurement Program's (ARM) site in North-Central Oklahoma in 2003. The radiometers were calibrated using two procedures, the so-called instantaneous ?tipcal? method and an automatic self-calibration algorithm. Measurements from the radiometers were in agreement, with less than a 0.4-K difference during clear skies, when the instantaneous method was applied. Brightness temperatures from the radiometer and the radiosonde showed an agreement of less than 0.55 K when the most recent absorption models were considered. Precipitable water vapor (PWV) computed from the radiometers were also compared to the PWV derived from a Global Positioning System station that operates at the ARM site. The instruments agree to within 0.1 cm in PWV retrieval

European attitudes to water pricing

DEFF Research Database (Denmark)

Jensen, Anne Kejser

2016-01-01

, there is a need for increased understanding of the implementation process and the attitudes towards implementation among the general public. This paper explores the spatial heterogeneity in the public attitude towards internalizing environmental and resource costs in the price of water across the EU regions....... Within an extensive spatial dataset constructed for the purpose, we estimate the effect of individual information levels and affordability concerns on the attitude towards environmental water pricing. Information about water problems is found to have a significant and positive effect on attitudes...

Actual problems of municipal cleaner’s waste waters

Directory of Open Access Journals (Sweden)

Konko¾ová Patrícia

2000-03-01

Full Text Available In paper are evaluated social and economical changes in water economy with emphasis on complex evaluation of municipal cleaner’s waste waters with respect of legislative, position of ownerskip relationskips and financial security of public experiences of water economy.

Long-Term Sensitization Training Primes "Aplysia" for Further Learning

Science.gov (United States)

Cleary, Leonard J.; Byrne, John H.; Antzoulatos, Evangelos G.; Wainwright, Marcy L.

2006-01-01

Repetitive, unilateral stimulation of "Aplysia" induces long-term sensitization (LTS) of ipsilaterally elicited siphon-withdrawal responses. Whereas some morphological effects of training appear only on ipsilateral sensory neurons, others appear bilaterally. We tested the possibility that contralateral morphological modifications may have…

Viewpoint: Expand your career horizons with a position abroad

DEFF Research Database (Denmark)

Harrod, Steven

2017-01-01

It’s job market season again. Are you sticking your toe in the water? Looking for a new challenge? A change of weather? Why not make a big splash and consider a position beyond your country’s borders? Of course, for decades institutions in English-speaking nations have filled their ranks with rec...

One-year Surveillance of Human Enteric Viruses in Raw and Treated Wastewaters, Downstream River Waters, and Drinking Waters.

Science.gov (United States)

Iaconelli, M; Muscillo, M; Della Libera, S; Fratini, M; Meucci, L; De Ceglia, M; Giacosa, D; La Rosa, G

2017-03-01

Human enteric viruses are a major cause of waterborne diseases, and can be transmitted by contaminated water of all kinds, including drinking and recreational water. The objectives of the present study were to assess the occurrence of enteric viruses (enterovirus, norovirus, adenovirus, hepatitis A and E virus) in raw and treated wastewaters, in rivers receiving wastewater discharges, and in drinking waters. Wastewater treatment plants' (WWTP) pathogen removal efficiencies by adenovirus quantitative real-time PCR and the presence of infectious enterovirus, by cell culture assays, in treated wastewaters and in surface waters were also evaluated. A total of 90 water samples were collected: raw and treated wastewaters (treated effluents and ultrafiltered water reused for industrial purposes), water from two rivers receiving treated discharges, and drinking water. Nested PCR assays were used for the identification of viral DNA/RNA, followed by direct amplicon sequencing. All raw sewage samples (21/21), 61.9 % of treated wastewater samples (13/21), and 25 % of ultrafiltered water samples (3/12) were contaminated with at least one viral family. Multiple virus families and genera were frequently detected. Mean positive PCRs per sample decreased significantly from raw to treated sewage and to ultrafiltered waters. Moreover, quantitative adenovirus data showed a reduction in excess of 99 % in viral genome copies following wastewater treatment. In surface waters, 78.6 % (22/28) of samples tested positive for one or more viruses by molecular methods, but enterovirus-specific infectivity assays did not reveal infectious particles in these samples. All drinking water samples tested negative for all viruses, demonstrating the effectiveness of treatment in removing viral pathogens from drinking water. Integrated strategies to manage water from all sources are crucial to ensure water quality.

Global Empowerment of Women in the Water Sector: A Mentoring Program through the Women-Water Nexus

Science.gov (United States)

Schifman, L. A.; Craver, V.

2017-12-01

According to a UNESCO report, women are underrepresented as world's researchers. Similarly, NSF recently reported that women hold less than one-fourth of senior faculty positions in academic institutions and research centers. These numbers are more staggering in countries outside of the U.S. For example, at the Jordan University of Science and Technology in the Middle East (Irbid, Jordan), only 4.6% of tenured positions in the faculty of engineering are women, with no female full professor appointments as of 2015. To address these issues, the Women-Water Nexus (WWN), part of the ASCE Environmental and Water Resources Institute, works to develop an international support network for water treatment and resources women scientists and engineers. We mainly focus on educational and professional development activities in order to increase the representation of women in leadership positions in academia, government, and private organizations. Here, we want to present and recruit mentors for our initiative called "Untapping the Power of Women in Water". The program will specifically be designed to support women in participating and preparing for professional international conferences. Any female researchers, scientists and engineers from the U.S., Turkey, Afghanistan, Jordan, and Kazakhstan could apply to be a mentee in the proposed program. While priority will be given to women in early- and mid-career positions as these types of activities are most valuable for promotion, we will support women across all career levels. The mentees will receive training from WWN mentors either through online tools such as webinars, or in-person workshops at the EWRI conference in Minneapolis, MN Jun 4-7, 2018. This initiative is currently under development and is supported in five countries: The United States, Turkey, Afghanistan, Jordan, and Kazakhstan. This program will promote essential skills for women to actively participate in the discussion and decision-making process related to

Condensate and feedwater systems, pumps, and water chemistry. Volume seven

International Nuclear Information System (INIS)

Anon.

1986-01-01

Subject matter includes condensate and feedwater systems (general features of condensate and feedwater systems, condenser hotwell level control, condensate flow, feedwater flow), pumps (principles of fluid flow, types of pumps, centrifugal pumps, positive displacement pumps, jet pumps, pump operating characteristics) and water chemistry (water chemistry fundamentals, corrosion, scaling, radiochemistry, water chemistry control processes, water pretreatment, PWR water chemistry, BWR water chemistry, condenser circulating water chemistry

The phylogenetic position of the solitary zoanthid genus Sphenopus (Cnidaria: Hexacorallia)

NARCIS (Netherlands)

Reimer, J.D.; Lin, M.; Fujii, T.

2012-01-01

The zoanthid genus Sphenopus (Cnidaria: Anthozoa: Zoantharia), like many other brachycnemic zoanthids, is found in shallow subtropical and tropical waters, but is uniquely unitary (solitary, monostomatous), azooxanthellate, and free-living. With sparse knowledge of its phylogenetic position, this

Quality-assurance results for routine water analysis in US Geological Survey laboratories, water year 1991

Science.gov (United States)

Maloney, T.J.; Ludtke, A.S.; Krizman, T.L.

1994-01-01

The US. Geological Survey operates a quality- assurance program based on the analyses of reference samples for the National Water Quality Laboratory in Arvada, Colorado, and the Quality of Water Service Unit in Ocala, Florida. Reference samples containing selected inorganic, nutrient, and low ionic-strength constituents are prepared and disguised as routine samples. The program goal is to determine precision and bias for as many analytical methods offered by the participating laboratories as possible. The samples typically are submitted at a rate of approximately 5 percent of the annual environmental sample load for each constituent. The samples are distributed to the laboratories throughout the year. Analytical data for these reference samples reflect the quality of environmental sample data produced by the laboratories because the samples are processed in the same manner for all steps from sample login through data release. The results are stored permanently in the National Water Data Storage and Retrieval System. During water year 1991, 86 analytical procedures were evaluated at the National Water Quality Laboratory and 37 analytical procedures were evaluated at the Quality of Water Service Unit. An overall evaluation of the inorganic (major ion and trace metal) constituent data for water year 1991 indicated analytical imprecision in the National Water Quality Laboratory for 5 of 67 analytical procedures: aluminum (whole-water recoverable, atomic emission spectrometric, direct-current plasma); calcium (atomic emission spectrometric, direct); fluoride (ion-exchange chromatographic); iron (whole-water recoverable, atomic absorption spectrometric, direct); and sulfate (ion-exchange chromatographic). The results for 11 of 67 analytical procedures had positive or negative bias during water year 1991. Analytical imprecision was indicated in the determination of two of the five National Water Quality Laboratory nutrient constituents: orthophosphate as phosphorus and

Local positive feedback and the persistence and recovery of fringe Avicennia marina (Forssk.) Vierh. mangroves

NARCIS (Netherlands)

Huisman, T.J.; Langevelde, van F.; Boer, de W.F.

2009-01-01

While mangrove restoration efforts are reasonably successful, failure often occurs in high wave energy situations. Due to differences in wave energy, seedling mortality rates vary strongly with position on the intertidal flat between high water spring and high water neap elevations. However, a local

Estimation of Water Requirements by Livestock in Europe

OpenAIRE

MUBAREKA Sarah; MAES JOACHIM; LAVALLE Carlo; DE ROO Arie

2013-01-01

The Blueprint to Safeguard Europe's Water aims to positively contribute to the European Union's Water Policy through a series of studies to assess the quantity and quality of this precious resource. An important part of that water balance is the accounting of water removed from rivers or aquifers by different sectorial needs. The map series presented here shows the water requirements for the livestock sector. These maps are calculated based on livestock density maps for 2005, normalized...

Conserved water molecules in bacterial serine hydroxymethyltransferases.

Science.gov (United States)

Milano, Teresa; Di Salvo, Martino Luigi; Angelaccio, Sebastiana; Pascarella, Stefano

2015-10-01

Water molecules occurring in the interior of protein structures often are endowed with key structural and functional roles. We report the results of a systematic analysis of conserved water molecules in bacterial serine hydroxymethyltransferases (SHMTs). SHMTs are an important group of pyridoxal-5'-phosphate-dependent enzymes that catalyze the reversible conversion of l-serine and tetrahydropteroylglutamate to glycine and 5,10-methylenetetrahydropteroylglutamate. The approach utilized in this study relies on two programs, ProACT2 and WatCH. The first software is able to categorize water molecules in a protein crystallographic structure as buried, positioned in clefts or at the surface. The other program finds, in a set of superposed homologous proteins, water molecules that occur approximately in equivalent position in each of the considered structures. These groups of molecules are referred to as 'clusters' and represent structurally conserved water molecules. Several conserved clusters of buried or cleft water molecules were found in the set of 11 bacterial SHMTs we took into account for this work. The majority of these clusters were not described previously. Possible structural and functional roles for the conserved water molecules are envisaged. This work provides a map of the conserved water molecules helpful for deciphering SHMT mechanism and for rational design of molecular engineering experiments. © The Author 2015. Published by Oxford University Press. All rights reserved. For Permissions, please e-mail: journals.permissions@oup.com.

ROMANIA: GEOGRAPHICAL AND GEOPOLITICAL POSITION

Directory of Open Access Journals (Sweden)

Ciprian Beniamin Benea

2016-12-01

Romania is identified in population reduction’s number, in missing trust in her successful evolution, falling agriculture and deforestation. All these negative aspects have pushed back Romania from geopolitical point of view. As solution for regaining its geopolitical role, Romanian must have an educated population, which would be conscious about the important connection between geography and education, and between Romania’s geographical position and the needed tools for promoting it from geopolitical point of view. Cough between East and West, Romania belongs to both areas; much more, in the context of climate change, Romania’s land, fresh water, and cheap water transport possibilities on Danube and Black Sea (and well beyond it must be used at their real capacities. Only in that moment Romania’s special geographical position will made Romania an active geopolitical actor, helping Romanians to determine its fate in a sustainable manner.

Experimental Study On Efficiency Of Solar Collector At Nagpur India During Winter

Directory of Open Access Journals (Sweden)

Jayant. V. Madan

2015-08-01

Full Text Available Abstract In this experimental study the active solar water heating direct circulation systems the thermo siphon solar flat plate collector has been tested at Government medical college 21.15N 79.09E Nagpur Maharashtra India. The various data needed are collected from Indian metrological department and during months from November to January i.e. during the winter season the responses from the system has been studied and analyzed. The maximum temperature was obtained was around 70c and the minimum ambient temperature was 18c. The objective of the present work is to evaluate efficiency of flat plate collector in Nagpur region considering these aspects of the flat plate collector both theoretically and experimentally. A test setup is fabricated and experiments conducted to study these aspects.

Range Cattle Winter Water Consumption in Northern Great Plains

Science.gov (United States)

Water consumption and DMI has been found to be positively correlated and may interact to alter range cow productivity. Environmental conditions can have a significant influence on water consumption during the winter. The objective of this study was to determine influences of water and air temperatur...

Side effects after myelography with Dimer Xsup(R) (Iocarmat) with subsequent positioning of the patients in the sitting or lying position

International Nuclear Information System (INIS)

Norstedt, M.

1982-01-01

92 patients were examined after lumbar myelography with the water-soluble contrast medium Iocarmat (Dimer Xsup(R)) in order to find out if side effects have any relation with the patient's position after the myelographic examination. In one group, the patients were laid with their upper part of the body positioned higher while the others were allowed to lie flat. The comparative investigation covering both groups of patients revealed the following results: 1) In 11% of the flat-lying patients there were generalised spasms which was not the case as far as the sitting patients were concerned. This is why the author advises against a flat positioning of the patient. 2) The frequency of headache decreased when the patients were lying flat which, however, does not mean a statistical significance. 3) Other side effects registered (myoclonus, tonic spasm in the legs, paraesthesia, increase in existing root pain and neck pain, nausea and vomiting) occurred in both groups nearly to the same extent, independently of the position of the patient. (orig./MG) [de

Automation of a battery of ion exchange columns for the determination of Pu in biological samples

International Nuclear Information System (INIS)

Jeanmaire, L.; Ballada, J.; Rigaudiere, R.; Patti, F.; Clanet, F.

1967-01-01

The document describes an apparatus allowing ten automatic and simultaneous determination of plutonium by ion exchange resins in urine. The constant flow rate reactants supply is realized by plastic siphons. The different determination phases are controlled by a programmer. (A.L.B.) [fr

Global positioning site environment evaluator

International Nuclear Information System (INIS)

Leffler, S.; Reeser, H.G.; Zaker, E.; Hansen, W.; Sikorski, R.W.

1990-01-01

Development of an innovative, integrated, automated system (Global Positioning Site Environment Evaluator - GPSEETM) for surveying contaminated waste sites is described. This system makes novel use of the Global Positioning System (GPS) satellite constellation for establishing specific locations and current times for surveying radioactive, hazardous, or mixed-waste sites. GPSEE may also be used for waste site contamination surveys after remediation activities to ensure environmental remediation is complete. A base station is established for collecting and recording data and directing field operations for field stations which may be located many miles from the base station. The field operators collect site surveying and contamination data utilizing a variety of chemical and radiological sensors. A major goal for the data collection process is to collect all data utilizing in situ sensors, thereby minimizing the need for collecting soil and water samples. Site contamination data is transmitted electronically to the base station for recording and processing. The GPSEE system is being developed for use at DOE/DOD and a variety of industrial facilities. 3 figs

A 30 m Resolution Surface Water Mask Including Estimation of Positional and Thematic Differences Using Landsat 8, SRTM and OpenStreetMap: A Case Study in the Murray-Darling Basin, Australia

Directory of Open Access Journals (Sweden)

Gennadii Donchyts

2016-05-01

Full Text Available Accurate maps of surface water are essential for many environmental applications. Surface water maps can be generated by combining measurements from multiple sources. Precise estimation of surface water using satellite imagery remains a challenging task due to the sensor limitations, complex land cover, topography, and atmospheric conditions. As a complementary dataset, in the case of hilly landscapes, a drainage network can be extracted from high-resolution digital elevation models. Additionally, Volunteered Geographic Information (VGI initiatives, such as OpenStreetMap, can also be used to produce high-resolution surface water masks. In this study, we derive a high-resolution water mask using Landsat 8 imagery and OpenStreetMap as well as (potential a drainage network using 30 m SRTM. Our approach to derive a surface water mask from Landsat 8 imagery comprises the use of a lower 15% percentile of Landsat 8 Top of Atmosphere (TOA reflectance from 2013 to 2015. We introduce a new non-parametric unsupervised method based on the Canny edge filter and Otsu thresholding to detect water in flat areas. For hilly areas, the method is extended with an additional supervised classification step used to refine the water mask. We applied the method across the Murray-Darling basin, Australia. Differences between our new Landsat-based water mask and the OpenStreetMap water mask regarding positional differences along the rivers and overall coverage were analyzed. Our results show that about 50% of the OpenStreetMap linear water features can be confirmed using the water mask extracted from Landsat 8 imagery and the drainage network derived from SRTM. We also show that the observed distances between river features derived from OpenStreetMap and Landsat 8 are mostly smaller than 60 m. The differences between the new water mask and SRTM-based linear features and hilly areas are slightly larger (110 m. The overall agreement between OpenStreetMap and Landsat 8 water

Structural properties of water around uncharged and charged carbon nanotubes

International Nuclear Information System (INIS)

Dezfoli, Amir Reza Ansari; Mehrabian, Mozaffar Ali; Rafsanjani, Hassan Hashemipour

2013-01-01

Studying the structural properties of water molecules around the carbon nanotubes is very important in a wide variety of carbon nanotubes applications. We studied the number of hydrogen bonds, oxygen and hydrogen density distributions, and water orientation around carbon nanotubes. The water density distribution for all carbon nanotubes was observed to have the same feature. In water-carbon nanotubes interface, a high-density region of water molecules exists around carbon nanotubes. The results reveal that the water orientation around carbon nanotubes is roughly dependent on carbon nanotubes surface charge. The water molecules in close distances to carbon nanotubes were found to make an HOH plane nearly perpendicular to the water-carbon nanotubes interface for carbon nanotubes with negative surface charge. For uncharged carbon nanotubes and carbon nanotubes with positive surface charge, the HOH plane was in tangential orientation with water-carbon nanotubes interface. There was also a significant reduction in hydrogen bond of water region around carbon nanotubes as compared with hydrogen bond in bulk water. This reduction was very obvious for carbon nanotubes with positive surface charge. In addition, the calculation of dynamic properties of water molecules in water-CNT interface revealed that there is a direct relation between the number of Hbonds and self-diffusion coefficient of water molecules

Identification and characterization of steady and occluded water in drinking water distribution systems.

Science.gov (United States)

Tong, Huiyan; Zhao, Peng; Zhang, Hongwei; Tian, Yimei; Chen, Xi; Zhao, Weigao; Li, Mei

2015-01-01

Deterioration and leakage of drinking water in distribution systems have been a major issue in the water industry for years, which are associated with corrosion. This paper discovers that occluded water in the scales of the pipes has an acidic environment and high concentration of iron, manganese, chloride, sulfate and nitrate, which aggravates many pipeline leakage accidents. Six types of water samples have been analyzed under the flowing and stagnant periods. Both the water in the exterior of the tubercles and stagnant water carry suspended iron particles, which explains the occurrence of "red water" when the system hydraulic conditions change. Nitrate is more concentrated in occluded water under flowing condition in comparison with that in flowing water. However, the concentration of nitrate in occluded water under stagnant condition is found to be less than that in stagnant water. A high concentration of manganese is found to exist in steady water, occluded water and stagnant water. These findings impact secondary pollution and the corrosion of pipes and containers used in drinking water distribution systems. The unique method that taking occluded water from tiny holes which were drilled from the pipes' exteriors carefully according to the positions of corrosion scales has an important contribution to research on corrosion in distribution systems. And this paper furthers our understanding and contributes to the growing body of knowledge regarding occluded environments in corrosion scales. Copyright © 2014 Elsevier Ltd. All rights reserved.

Microbiological quality of drinking water of urban and rural communities, Brazil

Directory of Open Access Journals (Sweden)

Giovani Nogueira

2003-04-01

Full Text Available OBJECTIVE: To evaluate the microbiological quality of treated and untreated water samples came from urban and rural communities and to examine the relationship between coliforms occurrence and average water temperature, and a comparison of the rainfall levels. METHODS: A sample of 3,073 untreated and treated (chlorinated water from taps (1,594, reservoir used to store treated water (1,033, spring water (96 and private well (350 collected for routine testing between 1996 and 1999 was analyzed by the multiple dilution tube methods used to detect the most probable number of total and fecal coliforms. These samples were obtained in the region of Maringá, state of Paraná, Brazil. RESULTS: The highest numbers water samples contaminated by TC (83% and FC (48% were found in the untreated water. TC and FC in samples taken from reservoirs used to store treated water was higher than that from taps midway along distribution lines. Among the treated water samples examined, coliform bacteria were found in 171 of the 1,033 sampling reservoirs. CONCLUSIONS: Insufficient treatment or regrowth is suggested by the observation that more than 17% of these treated potable water contained coliform. TC and FC positive samples appear to be similar and seasonally influenced in treated water. Two different periods must be considered for the occurrence of both TC and FC positive samples: (i a warm-weather period (September-March with high percentage of contaminated samples; and (ii cold-weather period (April-August were they are lower. Both TC and TF positive samples declined with the decreased of water temperature.

Microbiological quality of drinking water of urban and rural communities, Brazil

Directory of Open Access Journals (Sweden)

Nogueira Giovani

2003-01-01

Full Text Available OBJECTIVE: To evaluate the microbiological quality of treated and untreated water samples came from urban and rural communities and to examine the relationship between coliforms occurrence and average water temperature, and a comparison of the rainfall levels. METHODS: A sample of 3,073 untreated and treated (chlorinated water from taps (1,594, reservoir used to store treated water (1,033, spring water (96 and private well (350 collected for routine testing between 1996 and 1999 was analyzed by the multiple dilution tube methods used to detect the most probable number of total and fecal coliforms. These samples were obtained in the region of Maringá, state of Paraná, Brazil. RESULTS: The highest numbers water samples contaminated by TC (83% and FC (48% were found in the untreated water. TC and FC in samples taken from reservoirs used to store treated water was higher than that from taps midway along distribution lines. Among the treated water samples examined, coliform bacteria were found in 171 of the 1,033 sampling reservoirs. CONCLUSIONS: Insufficient treatment or regrowth is suggested by the observation that more than 17% of these treated potable water contained coliform. TC and FC positive samples appear to be similar and seasonally influenced in treated water. Two different periods must be considered for the occurrence of both TC and FC positive samples: (i a warm-weather period (September-March with high percentage of contaminated samples; and (ii cold-weather period (April-August were they are lower. Both TC and TF positive samples declined with the decreased of water temperature.

The Morphological Variations of Culex pipiens Larvae (Diptera: Culicidae in Yazd Province, Central Iran

Directory of Open Access Journals (Sweden)

H Dehghan

2010-12-01

Full Text Available "nAbstract "nBackground: Culex pipiens complex shows variations in morphological and biological characters including differ­ent biological forms and has medical and veterinary importance. Because of having morphological variations, some­times it is not easy to separate this species from Cx. quinquefasciatus and Cx. torrentium. The aim of this study was to  identify the  Culex pipiens complex species in order to use in control programs in the future. "nMethods: This study was carried out in two randomly selected rural villages in Yazd County, eastern Iran using dip­ping technique from April to October 2009. The data were analyzed using SPSS software version 16. "nResults: Average of siphon index in fourth-instrar larvae was 3.86±0.03, the minimum and maximum were calculated 2.43 and 5.14, respectively. Siphon/Saddle index was measured as average, minimum and maximum 3.2±0.2, 2.78, and 4.42 respectively. In our study, only 4 specimens had single seta 1 on segments III and VI (2.5% and the remaining beard double seta (97.5%. The maximum 3-6 branches seta 1a-S and 1b-S (95% were observed on siphon. "nConclusion: More populations of Culex pipiens from different areas of Iran need to be studied to gain complete informa­tion about the taxonomy and ecology of the species in the country. "n  "nKeywords: Culex pipiens complex, larvae, taxonomy, Iran

Flashing oscillation in pool water

International Nuclear Information System (INIS)

Takamasa, Tomoji; Kondo, Koichi; Hazuku, Tatsuya

1996-01-01

This paper presents an experimental study of high-pressure saturated water discharging into the pool water. The purpose of the experiment is to clarify the phenomena that occur in blow-down of high-pressure saturated water from the pressure vessel into the water-filled containment in the case of a wall-crack accident or a LOCA in an advanced reactor. The results revealed that a flashing oscillation (FO) occurs when high-pressure saturated water discharges into the pool water, under specified experimental settings. The range of the flashing oscillates between a point very close to and some distance from the vent hole. The pressures in the vent tube and pool water vary according to the flashing oscillation. The pressure oscillation and frequency of flashing position might be caused by the balancing action between the supply of saturated water, flashing at the control volume and its condensation on the steam-water interface. A linear analysis was conducted using a spherical flashing bubble model. The period of the flashing oscillation in the experiments can be explained by theoretical analysis

Slowly biodegradable organic compounds impact the biostability of non-chlorinated drinking water produced from surface water.

Science.gov (United States)

Hijnen, W A M; Schurer, R; Bahlman, J A; Ketelaars, H A M; Italiaander, R; van der Wal, A; van der Wielen, P W J J

2018-02-01

It is possible to distribute drinking water without a disinfectant residual when the treated water is biologically stable. The objective of this study was to determine the impact of easily and slowly biodegradable compounds on the biostability of the drinking water at three full-scale production plants which use the same surface water, and on the regrowth conditions in the related distribution systems. Easily biodegradable compounds in the drinking water were determined with AOC-P17/Nox during 2012-2015. Slowly biodegradable organic compounds measured as particulate and/or high-molecular organic carbon (PHMOC), were monitored at the inlet and after the different treatment stages of the three treatments during the same period. The results show that PHMOC (300-470 μg C L -1 ) was approximately 10% of the TOC in the surface water and was removed to 50-100 μg C L -1 . The PHMOC in the water consisted of 40-60% of carbohydrates and 10% of proteins. A significant and strong positive correlation was observed for PHMOC concentrations and two recently introduced bioassay methods for slowly biodegradable compounds (AOC-A3 and biomass production potential, BPC 14 ). Moreover, these three parameters in the biological active carbon effluent (BACF) of the three plants showed a positive correlation with regrowth in the drinking water distribution system, which was assessed with Aeromonas, heterotrophic plate counts, coliforms and large invertebrates. In contrast, the AOC-P17/Nox concentrations did not correlate with these regrowth parameters. We therefore conclude that slowly biodegradable compounds in the treated water from these treatment plants seem to have a greater impact on regrowth in the distribution system than easily biodegradable compounds. Copyright © 2017 Elsevier Ltd. All rights reserved.

Pharmaceutical compounds in drinking water

Directory of Open Access Journals (Sweden)

Vikas Chander

2016-06-01

Full Text Available Pharmaceutical products and their wastes play a major role in the degradation of environment. These drugs have positive as well as negative consequences on different environmental components including biota in different ways. Many types of pharmaceutical substances have been detected with significant concentrations through various advanced instrumental techniques in surface water, subsurface water, ground water, domestic waste water, municipal waste water and industrial effluents. The central as well as state governments in India are providing supports by creating excise duty free zones to promote the pharmaceutical manufacturers for their production. As a result, pharmaceutical companies are producing different types of pharmaceutical products at large scale and also producing complex non-biodegradable toxic wastes byproducts and releasing untreated or partially treated wastes in the environment in absence of strong regulations. These waste pollutants are contaminating all types of drinking water sources. The present paper focuses on water quality pollution by pharmaceutical pollutants, their occurrences, nature, metabolites and their fate in the environment.

Water Reserves Program. An adaptation strategy to prevent imbalance of water in nature

Science.gov (United States)

Salinas-Rodriguez, S. A.; López Pérez, M.; Barrios Ordóñez, J.; Wickel, B.; Villón Bracamonte, R. A.

2013-12-01

Freshwater ecosystems occupy approximately 1% of the earth's surface yet possess about 12% of all known animal species. By virtue of their position in the landscape they connect terrestrial and coastal marine biomes and provide and sustain ecosystem services vital to the health and persistence of human communities. These services include the supply of water for food production, urban and industrial consumption, among others. Over the past century many freshwater ecosystems around the world have been heavily modified or lost due to the alteration of flow regimes (e.g. damming, canalization, diversion, over-abstraction). The synergistic impacts of land use change, changes in flows, chemical deterioration, and climate change have left many systems and their species very little room to adjust to change, while future projections indicate a steady increase imbalance in water demand for food and energy production and water supply to suit the needs of a growing world population. In Mexico, the focus has been to secure water for human development and maximize economic growth, which has resulted in allocation of water beyond available amounts, and that in many river basins has led imbalance of water in nature. As a consequence episodic water scarcity severely constrains freshwater ecosystems and the services they provide. Climatic change and variability are presenting serious challenges to a country that already is experiencing serious strain on its water resources. However, freshwater ecosystems are recognized by law as legitimate user of water, and mandate a flow allocation for the environment ('water reserve' or 'environmental flows'). Based on this legal provision the Mexican government through the National Water Commission (Conagua), with support of the Alliance WWF - Fundación Gonzalo Río Arronte, and the Interamerican Development Bank, has launched a national program to identify and implement 'water reserves': basins where environmental flows will be secured and

Asexual propagation in the coral reef macroalga Halimeda (Chlorophyta, Bryopsidales) : production, dispersal and attachment of small fragments

NARCIS (Netherlands)

Walters, LJ; Coyer, JA; Hunter, CL; Beach, KS; Vroom, PS

2002-01-01

Siphonous, green macroalgae of the genus Halimeda are ubiquitous and ecologically important in tropical and subtropical marine environments. It has been hypothesized that the abundance of Halimeda on coral reefs is in part due to the ability of this genus to propagate asexually via vegetative

Challenges to Sustainable Safe Drinking Water: A Case Study of Water Quality and Use across Seasons in Rural Communities in Limpopo Province, South Africa

Directory of Open Access Journals (Sweden)

Joshua N. Edokpayi

2018-02-01

Full Text Available Consumption of microbial-contaminated water can result in diarrheal illnesses and enteropathy with the heaviest impact upon children below the age of five. We aimed to provide a comprehensive analysis of water quality in a low-resource setting in Limpopo province, South Africa. Surveys were conducted in 405 households in rural communities of Limpopo province to determine their water-use practices, perceptions of water quality, and household water-treatment methods. Drinking water samples were tested from households for microbiological contamination. Water from potential natural sources were tested for physicochemical and microbiological quality in the dry and wet seasons. Most households had their primary water source piped into their yard or used an intermittent public tap. Approximately one third of caregivers perceived that they could get sick from drinking water. All natural water sources tested positive for fecal contamination at some point during each season. The treated municipal supply never tested positive for fecal contamination; however, the treated system does not reach all residents in the valley; furthermore, frequent shutdowns of the treatment systems and intermittent distribution make the treated water unreliable. The increased water quantity in the wet season correlates with increased treated water from municipal taps and a decrease in the average contaminant levels in household water. This research suggests that wet season increases in water quantity result in more treated water in the region and that is reflected in residents’ water-use practices.

High prevalence of enteric viruses in untreated individual drinking water sources and surface water in Slovenia.

Science.gov (United States)

Steyer, Andrej; Torkar, Karmen Godič; Gutiérrez-Aguirre, Ion; Poljšak-Prijatelj, Mateja

2011-09-01

Waterborne infections have been shown to be important in outbreaks of gastroenteritis throughout the world. Although improved sanitary conditions are being progressively applied, fecal contaminations remain an emerging problem also in developed countries. The aim of our study was to investigate the prevalence of fecal contaminated water sources in Slovenia, including surface waters and groundwater sources throughout the country. In total, 152 water samples were investigated, of which 72 samples represents groundwater from individual wells, 17 samples from public collection supplies and 63 samples from surface stream waters. Two liters of untreated water samples were collected and concentrated by the adsorption/elution technique with positively charged filters followed by an additional ultracentrifugation step. Group A rotaviruses, noroviruses (genogroups I and II) and astroviruses were detected with real-time RT-PCR method in 69 (45.4%) out of 152 samples collected, of which 31/89 (34.8%) drinking water and 38/63 (60.3%) surface water samples were positive for at least one virus tested. In 30.3% of drinking water samples group A rotaviruses were detected (27/89), followed by noroviruses GI (2.2%; 2/89) and astroviruses (2.2%; 2/89). In drinking groundwater samples group A rotaviruses were detected in 27 out of 72 tested samples (37.5%), genogroup I noroviruses in two (2.8%), and human astroviruses in one (1.4%) samples. In surface water samples norovirus genogroup GII was the most frequently detected (41.3%; 26/63), followed by norovirus GI (33.3%; 21/63), human astrovirus (27.0%; 17/63) and group A rotavirus (17.5%; 11/63). Our study demonstrates relatively high percentage of groundwater contamination in Slovenia and, suggests that raw groundwater used as individual drinking water supply may constitute a possible source of enteric virus infections. In the future, testing for enteric viruses should be applied for drinking water sources in waterborne outbreaks

Meteorological applications of a surface network of Global Positioning System receivers

NARCIS (Netherlands)

Haan, de S.

2008-01-01

This thesis presents meteorological applications of water vapour observations from a surface network of Global Positioning System (GPS) receivers. GPS signals are delayed by the atmo¬sphere due to atmospheric refraction and bending. Mapped to the zenith, this delay is called Zenith Total Delay

Relative positions of the hydroxyl and water vapor astrophysical masers

International Nuclear Information System (INIS)

Mader, G.L.

1975-01-01

The 22 GHz H 2 O and the 1.6 GHz OH emission from W3(OH), W49N, W51 and VY Canis Majoris were simultaneously observed with a very long baseline interferometer (VLBI) in order to accurately determine the relative positions of these masering regions in each source. By observing the OH and H 2 O emission simultaneously, the effects of frequency standard instability and of the troposphere were eliminated and the effects of the ionosphere were minimized. The observing and data reduction techniques as well as the modifications to existing equipment and the construction of new equipment are described. The OH observations include the 1665-MHz line in both left and right circular polarization in W49N and W3(OH), the 1667-MHz RCP line in W3(OH), the 1667-MHz LCP line in W49N, and the 1665-MHz LCP line in W51. VY CMa was observed at 1667-MHz RCP and 1612-MHz LCP

Photocatalysis in Generation of Hydrogen from Water

KAUST Repository

Takanabe, Kazuhiro

2015-04-18

Solar energy can be converted by utilizing the thermal or photoelectric effects of photons. Concentrated solar power systems utilize thermal energy from the sun by either making steam and then generating power or shifting the chemical equilibrium of a reaction (e.g., water splitting or CO2 reduction) that occurs at extremely high temperatures. The photocatalytic system contains powder photocatalysts. Each photocatalyst particle should collect sufficient photons from the solar flux to cause the required multielectron reactions to occur. The band gap and band edge positions of semiconductors are the most critical parameters for assessing the suitability of photocatalysts for overall water splitting. The most important requirement when selecting photocatalyst materials is the band positions relative to hydrogen and oxygen evolution potentials. For most photocatalysts, surface modification by cocatalysts was found to be essential to achieve overall water splitting.

Water and tourism on Mediterranean islands

Energy Technology Data Exchange (ETDEWEB)

Igel, Wolf von; Candela, Lucila [Technical Univ. of Catalonia, Barcelona (Spain). Geotechnical Engineering and Geosciences Dept.

2005-07-01

An increased tourism development has taken place in the Mediterranean basin. This has induced some positive and negative consequences over diverse aspects of life and the natural system. One important consequence has been the increasing pressure put on natural resources, namely on fresh water resources. The patterns of water use related to tourism activity that lead to a situation of scarcity of water resources in a Mediterranean islands context are presented. Next are presented the main problems of hydrological, environmental and socio-economic nature that are a consequence of the increasing tourism development and accompanying increasing scarcity of water resources. As one of these main problems is often the insufficient water supply to meet the water demand, a discussion of the pros and cons of the diverse alternatives to increase the water supply and an explanation of some alternatives to control the water demand are presented. (orig.)

Characteristics of pulse corona discharge over water surface

Science.gov (United States)

Fujii, Tomio; Arao, Yasushi; Rea, Massimo

2008-12-01

Production of ozone and OH radical is required to advance the plasma chemical reactions in the NOx removal processes for combustion gas treatment. The corona discharge to the water surface is expected to induce the good conditions for the proceeding of the NO oxidation and the NO2 dissolution removal into water. In order to get the fundamental data of the corona discharge over the water surface, the positive and negative V-I characteristics and the ozone production were measured with the multi needle and the saw-edge type of the discharge electrodes. The pulse corona characteristics were also measured with some different waveforms of the applied pulse voltage. The experiments were carried out under the atmospheric pressure and room temperature. Both the DC and the pulse corona to the water surface showed a stable and almost the same V-I characteristics as to plate electrodes though the surface of water was waved by corona wind. The positive streamer corona showed more ozone production than the negative one both in the DC and in the pulse corona.

Characteristics of pulse corona discharge over water surface

International Nuclear Information System (INIS)

Fujii, Tomio; Arao, Yasushi; Rea, Massimo

2008-01-01

Production of ozone and OH radical is required to advance the plasma chemical reactions in the NOx removal processes for combustion gas treatment. The corona discharge to the water surface is expected to induce the good conditions for the proceeding of the NO oxidation and the NO 2 dissolution removal into water. In order to get the fundamental data of the corona discharge over the water surface, the positive and negative V-I characteristics and the ozone production were measured with the multi needle and the saw-edge type of the discharge electrodes. The pulse corona characteristics were also measured with some different waveforms of the applied pulse voltage. The experiments were carried out under the atmospheric pressure and room temperature. Both the DC and the pulse corona to the water surface showed a stable and almost the same V-I characteristics as to plate electrodes though the surface of water was waved by corona wind. The positive streamer corona showed more ozone production than the negative one both in the DC and in the pulse corona.

Urban water sustainability: an integrative framework for regional water management

Science.gov (United States)

Gonzales, P.; Ajami, N. K.

2015-11-01

Traditional urban water supply portfolios have proven to be unsustainable under the uncertainties associated with growth and long-term climate variability. Introducing alternative water supplies such as recycled water, captured runoff, desalination, as well as demand management strategies such as conservation and efficiency measures, has been widely proposed to address the long-term sustainability of urban water resources. Collaborative efforts have the potential to achieve this goal through more efficient use of common pool resources and access to funding opportunities for supply diversification projects. However, this requires a paradigm shift towards holistic solutions that address the complexity of hydrologic, socio-economic and governance dynamics surrounding water management issues. The objective of this work is to develop a regional integrative framework for the assessment of water resource sustainability under current management practices, as well as to identify opportunities for sustainability improvement in coupled socio-hydrologic systems. We define the sustainability of a water utility as the ability to access reliable supplies to consistently satisfy current needs, make responsible use of supplies, and have the capacity to adapt to future scenarios. To compute a quantitative measure of sustainability, we develop a numerical index comprised of supply, demand, and adaptive capacity indicators, including an innovative way to account for the importance of having diverse supply sources. We demonstrate the application of this framework to the Hetch Hetchy Regional Water System in the San Francisco Bay Area of California. Our analyses demonstrate that water agencies that share common water supplies are in a good position to establish integrative regional management partnerships in order to achieve individual and collective short-term and long-term benefits.

Presence of rotavirus and free-living amoebae in the water supplies of Karachi, Pakistan

Science.gov (United States)

Yousuf, Farzana Abubakar; Siddiqui, Ruqaiyyah; Khan, Naveed Ahmed

2017-01-01

ABSTRACT Rotavirus and pathogenic free-living amoebae are causative agents of important health problems, especially for developing countries like Pakistan where the population has limited access to clean water supplies. Here, we evaluated the prevalence of rotavirus and free-living amoebae (Acanthamoeba spp., Balamuthia mandrillaris, Naegleria fowleri) in drinking water supplies of Karachi, Pakistan. Six water filtration plants that supply drinking water to the population of Karachi were investigated. Additionally, drinking water samples from households were analyzed for the presence of rotavirus and free-living amoebae. Rotavirus was present in 35% of the water samples collected from water filtration plants; however, domestic tap water samples had a prevalence of only 5%. Out of 20 water samples from filtration plants, 13 (65%) were positive for Acanthamoeba spp., and one (5%) was positive for B. mandrillaris. Out of 20 drinking water samples collected from different areas of Karachi, 35% were positive for Acanthamoeba spp. Rotavirus was detected in 5% of the drinking water samples tested. Overall, these findings showed for the first time the presence of rotavirus, in addition to pathogenic free-living amoebae in drinking water supplies of Karachi that could be an important public health risk for the affected population. PMID:28591260

Presence of rotavirus and free-living amoebae in the water supplies of Karachi, Pakistan

Directory of Open Access Journals (Sweden)

Farzana Abubakar Yousuf

Full Text Available ABSTRACT Rotavirus and pathogenic free-living amoebae are causative agents of important health problems, especially for developing countries like Pakistan where the population has limited access to clean water supplies. Here, we evaluated the prevalence of rotavirus and free-living amoebae (Acanthamoeba spp., Balamuthia mandrillaris, Naegleria fowleri in drinking water supplies of Karachi, Pakistan. Six water filtration plants that supply drinking water to the population of Karachi were investigated. Additionally, drinking water samples from households were analyzed for the presence of rotavirus and free-living amoebae. Rotavirus was present in 35% of the water samples collected from water filtration plants; however, domestic tap water samples had a prevalence of only 5%. Out of 20 water samples from filtration plants, 13 (65% were positive for Acanthamoeba spp., and one (5% was positive for B. mandrillaris. Out of 20 drinking water samples collected from different areas of Karachi, 35% were positive for Acanthamoeba spp. Rotavirus was detected in 5% of the drinking water samples tested. Overall, these findings showed for the first time the presence of rotavirus, in addition to pathogenic free-living amoebae in drinking water supplies of Karachi that could be an important public health risk for the affected population.

Theoretical vibrational sum-frequency generation spectroscopy of water near lipid and surfactant monolayer interfaces

Energy Technology Data Exchange (ETDEWEB)

Roy, S.; Gruenbaum, S. M.; Skinner, J. L. [Theoretical Chemistry Institute and Department of Chemistry, 1101 University Ave., University of Wisconsin-Madison, Madison, Wisconsin 53706 (United States)

2014-11-14

Understanding the structure of water near cell membranes is crucial for characterizing water-mediated events such as molecular transport. To obtain structural information of water near a membrane, it is useful to have a surface-selective technique that can probe only interfacial water molecules. One such technique is vibrational sum-frequency generation (VSFG) spectroscopy. As model systems for studying membrane headgroup/water interactions, in this paper we consider lipid and surfactant monolayers on water. We adopt a theoretical approach combining molecular dynamics simulations and phase-sensitive VSFG to investigate water structure near these interfaces. Our simulated spectra are in qualitative agreement with experiments and reveal orientational ordering of interfacial water molecules near cationic, anionic, and zwitterionic interfaces. OH bonds of water molecules point toward an anionic interface leading to a positive VSFG peak, whereas the water hydrogen atoms point away from a cationic interface leading to a negative VSFG peak. Coexistence of these two interfacial water species is observed near interfaces between water and mixtures of cationic and anionic lipids, as indicated by the presence of both negative and positive peaks in their VSFG spectra. In the case of a zwitterionic interface, OH orientation is toward the interface on the average, resulting in a positive VSFG peak.

Observing position and movements in hydrotherapy: a pilot study.

Science.gov (United States)

Stark, Mary Ann; Rudell, Barb; Haus, George

2008-01-01

To observe and describe the positions and movements women choose while immersed in water during the first stage of labor. Descriptive, observational pilot study. A rural community hospital that provided hydrotherapy in labor. Women (N = 7) who intended to use hydrotherapy in labor were recruited prenatally from a midwife-managed practice. For 15 minutes of each hour during the first stage of labor, position and movements of the participants were observed and recorded on a laptop computer. The observational tool was developed for this study from a review of the literature and interviews with nursing experts; 435 observations were recorded. Women were free to choose when and how long to use hydrotherapy and had no restriction on their positions and movements. Only 3 of the 7 participants labored in the tub. Women demonstrated a greater range of positions and movements in the tub than in bed, both throughout labor and during late first-stage labor (7-10 cm of dilatation). Women had more contractions and made more rhythmic movements while in the tub than in bed. Hydrotherapy may encourage upright positions and movements that facilitate labor progress and coping, helping women avoid unnecessary interventions.

Microbiological evaluation of water during the 2011 flood crisis in Thailand

International Nuclear Information System (INIS)

Chaturongkasumrit, Yuphakhun; Techaruvichit, Punnida; Takahashi, Hajime; Kimura, Bon; Keeratipibul, Suwimon

2013-01-01

In 2011, a severe flood occurred in Thailand, covering nearly half the country in water for several months. The contamination of floodwater and subsequent contamination of water for human consumption could have potentially led to a widespread health crisis. However, to date, no study has been conducted to determine the safety of the waters used for human consumption in Thailand during the severe flood. Therefore, we conducted microbiological analysis of 4 kinds of water (floodwater, river water, tap water, and filtered tap water) collected from industrial and residential areas that were damaged due to flooding. Higher net levels of bacteria were found in water with a higher turbidity. No clear trend was observed in the pH value of all 4 water samples. The level of total bacterial contamination in the water samples was estimated by real-time quantitative polymerase chain reaction (PCR). Eleven of the 12 tap water samples and all of the filtered tap water samples had a total bacterial load that exceeded the Thai water quality standards. One of the tap water samples and one of the filtered tap water samples were found to be positive for Shigella sp., although none of the floodwater samples showed detectable levels of this pathogen as determined by PCR analysis. One of the samples of floodwater was also found to be positive for Leptospira sp., but none of the tap water or filtered tap water samples were positive. Most of the tap water samples and all filtered tap water samples were found to be contaminated with Vibrio cholerae. Bacterial contamination in water samples was also analyzed by denaturing gradient gel electrophoresis (DGGE) analysis. These results revealed that several microorganisms were transferred via floodwater to different areas in the central part of Thailand and cross-contaminated between floodwater and water for human consumption. - Highlights: • We investigated the flood impact on the waters used for human consumption. • Higher net levels of

Microbiological evaluation of water during the 2011 flood crisis in Thailand

Energy Technology Data Exchange (ETDEWEB)

Chaturongkasumrit, Yuphakhun; Techaruvichit, Punnida; Takahashi, Hajime; Kimura, Bon [Department of Food Science and Technology, Faculty of Marine Science, Tokyo University of Marine Science and Technology, Tokyo 108-8477 (Japan); Keeratipibul, Suwimon, E-mail: Suwimon.k@chula.ac.th [Department of Food Technology, Faculty of Science, Chulalongkorn University, Phayathai Road, Bangkok 10330 (Thailand)

2013-10-01

In 2011, a severe flood occurred in Thailand, covering nearly half the country in water for several months. The contamination of floodwater and subsequent contamination of water for human consumption could have potentially led to a widespread health crisis. However, to date, no study has been conducted to determine the safety of the waters used for human consumption in Thailand during the severe flood. Therefore, we conducted microbiological analysis of 4 kinds of water (floodwater, river water, tap water, and filtered tap water) collected from industrial and residential areas that were damaged due to flooding. Higher net levels of bacteria were found in water with a higher turbidity. No clear trend was observed in the pH value of all 4 water samples. The level of total bacterial contamination in the water samples was estimated by real-time quantitative polymerase chain reaction (PCR). Eleven of the 12 tap water samples and all of the filtered tap water samples had a total bacterial load that exceeded the Thai water quality standards. One of the tap water samples and one of the filtered tap water samples were found to be positive for Shigella sp., although none of the floodwater samples showed detectable levels of this pathogen as determined by PCR analysis. One of the samples of floodwater was also found to be positive for Leptospira sp., but none of the tap water or filtered tap water samples were positive. Most of the tap water samples and all filtered tap water samples were found to be contaminated with Vibrio cholerae. Bacterial contamination in water samples was also analyzed by denaturing gradient gel electrophoresis (DGGE) analysis. These results revealed that several microorganisms were transferred via floodwater to different areas in the central part of Thailand and cross-contaminated between floodwater and water for human consumption. - Highlights: • We investigated the flood impact on the waters used for human consumption. • Higher net levels of

Demineralised water cooling in the LHC accelerator

CERN Document Server

Peón-Hernández, G

2002-01-01

In spite of the LHC accelerator being a cryogenic machine, it remains nevertheless a not negligible heat load to be removed by conventional water-cooling. About 24MW will be taken away by demineralised water cooled directly by primary water from the LHC cooling towers placed at the even points. This paper describes the demineralised water network in the LHC tunnel including pipe diameters, lengths, water speed, estimated friction factor, head losses and available supply and return pressures for each point. It lists all water cooled equipment, highlights the water cooled cables as the most demanding equipment followed by the radio frequency racks and cavities, and by the power converters. Their main cooling requirements and their positions in the tunnel are also presented.

GPS Position Time Series @ JPL

Science.gov (United States)

Owen, Susan; Moore, Angelyn; Kedar, Sharon; Liu, Zhen; Webb, Frank; Heflin, Mike; Desai, Shailen

2013-01-01

Different flavors of GPS time series analysis at JPL - Use same GPS Precise Point Positioning Analysis raw time series - Variations in time series analysis/post-processing driven by different users. center dot JPL Global Time Series/Velocities - researchers studying reference frame, combining with VLBI/SLR/DORIS center dot JPL/SOPAC Combined Time Series/Velocities - crustal deformation for tectonic, volcanic, ground water studies center dot ARIA Time Series/Coseismic Data Products - Hazard monitoring and response focused center dot ARIA data system designed to integrate GPS and InSAR - GPS tropospheric delay used for correcting InSAR - Caltech's GIANT time series analysis uses GPS to correct orbital errors in InSAR - Zhen Liu's talking tomorrow on InSAR Time Series analysis

Passive anti-frosting surfaces using microscopic ice arrays

Science.gov (United States)

Ahmadi, Farzad; Nath, Saurabh; Iliff, Grady; Boreyko, Jonathan

2017-11-01

Despite exceptional advances in surface chemistry and micro/nanofabrication, no engineered surface has been able to passively suppress the in-plane growth of frost occurring in humid, subfreezing environments. Motivated by this, and inspired by the fact that ice itself can evaporate nearby liquid water droplets, we present a passive anti-frosting surface in which the majority of the surface remains dry indefinitely. We fabricated an aluminum surface exhibiting an array of small metallic fins, where a wicking micro-groove was laser-cut along the top of each fin to produce elevated water ``stripes'' that freeze into ice. As the saturation vapor pressure of ice is less than that of supercooled liquid water, the ice stripes serve as overlapping humidity sinks that siphon all nearby moisture from the air and prevent condensation and frost from forming anywhere else on the surface. Our experimental results show that regions between stripes remain dry even after 24 hours of operation under humid and supercooled conditions. We believe that the presented anti-frosting technology has the potential to help solve the world's multi-billion dollar frosting problem that adversely affects transportation, power generation, and HVAC systems.

Is water age a reliable indicator for evaluating water quality effectiveness of water diversion projects in eutrophic lakes?

Science.gov (United States)

Zhang, Xiaoling; Zou, Rui; Wang, Yilin; Liu, Yong; Zhao, Lei; Zhu, Xiang; Guo, Huaicheng

2016-11-01

Water diversion has been applied increasingly to promote the exchange of lake water and to control eutrophication of lakes. The accelerated water exchange and mass transport by water diversion can usually be represented by water age. But the responses of water quality after water diversion is still disputed. The reliability of using water age for evaluating the effectiveness of water diversion projects in eutrophic lakes should be thereby explored further. Lake Dianchi, a semi-closed plateau lake in China, has suffered severe eutrophication since the 1980s, and it is one of the three most eutrophic lakes in China. There was no significant improvement in water quality after an investment of approximately 7.7 billion USD and numerous project efforts from 1996 to 2015. After the approval of the Chinese State Council, water has been transferred to Lake Dianchi to alleviate eutrophication since December 2013. A three-dimensional hydrodynamic and water quality model and eight scenarios were developed in this study to quantity the influence of this water diversion project on water quality in Lake Dianchi. The model results showed that (a) Water quality (TP, TN, and Chla) could be improved by 13.5-32.2%, much lower than the approximate 50% reduction in water age; (b) Water exchange had a strong positive relationship with mean TP, and mean Chla had exactly the same response to water diversion as mean TN; (c) Water level was more beneficial for improving hydrodynamic and nutrient concentrations than variation in the diverted inflowing water volume; (d) The water diversion scenario of doubling the diverted inflow rate in the wet season with the water level of 1886.5 m and 1887 m in the remaining months was the best water diversion mode for mean hydrodynamics and TP, but the scenario of doubling the diverted inflow rate in the wet season with 1887 m throughout the year was optimum for mean TN and Chla; (e) Water age influenced the effectiveness of water diversion on the

Method for steam generator water level measurement

International Nuclear Information System (INIS)

Srinivasan, J.S.

1991-01-01

This paper describes a nuclear power plant, a method of controlling the steam generator water level, wherein the steam generator has an upper level tap corresponding to an upper level, a lower level, a riser positioned between the lower and upper taps, and level sensor means for indicating water level between a first range limit and a second range limit, the sensor means being connected to at least the lower tap. It comprises: calculating a measure of velocity head at about the lower level tap; calculating a measure of full water level as the upper level less the measure of velocity head; calibrating the level sensor means to provide an output at the first limit corresponding to an input thereto representative of the measure of full level; calculating a high level setpoint equal to the level of the riser less a bias amount which is a function of the position of the riser relative to the span between the taps; and controlling the water level when the sensor means indicates that the high level setpoint has been reached

Yeasts and filamentous fungi in bottled mineral water and tap water from municipal supplies

Directory of Open Access Journals (Sweden)

Mirian Ueda Yamaguchi

2007-01-01

Full Text Available The main objective of this study was to analyse the occurrence of yeasts and filamentous fungi in drinking water as well as to investigate their correlation with the indicator bacteria of faecal pollution. Yeasts were detected in 36.6% and 11.6% of the bottled mineral on water dispensers and tap water samples from municipal system, respectively. Twenty-one (35.0% of bottled mineral water and two (3.3% of tap water samples were positive for filamentous fungi. For bottled mineral water 12 (20.0% of 60 samples were positive for total coliform, compared with 3(5.0%out of 60 samples from tap water. The mineral water from dispensers was more contaminated than tap water. Strains belonging to the genera Candida identified to the species level were C. parapsilosis, C. glabrata and C. albicans. Thus, bottled mineral water from water dispensers and tap water could be considered a possible transmission route for filamentous fungi and yeasts, and could constitute a potential health hazard, mainly to immunocompromised indivuals.O principal objetivo do presente estudo foi avaliar a prevalência de leveduras e fungos filamentosos em água potável, bem como investigar suas correlações com bactérias indicadoras de contaminação fecal. Leveduras foram detectadas em 36,6% e 11,6% das amostras de água mineral de garrafão em dispensadores de água e água de torneira do sistema municipal, respectivamente. Vinte e uma (35,5% das amostras de água mineral de garrafão e duas (3,3% das amostras de água de torneira foram positivas para fungos filamentosos. Para água mineral de garrafão, 12 (20.0% das 60 amostras foram positivas para coliforme total, comparado com 3 (5.0% das 60 amostras de água de torneira. A água coletada de garrafões de água mineral dos dispensadores foi marcadamente mais contaminada que as amostras de água de torneira. Candida spp identificadas ao nível de espécie foram C. parapsilosis, C. glabrata e C. albicans. Como está sendo

Contaminated water treatment

Science.gov (United States)

Gormly, Sherwin J. (Inventor); Flynn, Michael T. (Inventor)

2010-01-01

Method and system for processing of a liquid ("contaminant liquid") containing water and containing urine and/or other contaminants in a two step process. Urine, or a contaminated liquid similar to and/or containing urine and thus having a relatively high salt and urea content is passed through an activated carbon filter to provide a resulting liquid, to remove most of the organic molecules. The resulting liquid is passed through a semipermeable membrane from a membrane first side to a membrane second side, where a fortified drink having a lower water concentration (higher osmotic potential) than the resulting liquid is positioned. Osmotic pressure differential causes the water, but not most of the remaining inorganic (salts) contaminant(s) to pass through the membrane to the fortified drink. Optionally, the resulting liquid is allowed to precipitate additional organic molecules before passage through the membrane.

Detection of shielded radionuclides from weak and poorly resolved spectra using group positive RIVAL

International Nuclear Information System (INIS)

Kump, Paul; Bai, Er-Wei; Chan, Kung-Sik; Eichinger, William

2013-01-01

This paper is concerned with the identification of nuclides from weak and poorly resolved spectra in the presence of unknown radiation shielding materials such as carbon, water, concrete and lead. Since a shield will attenuate lower energies more so than higher ones, isotope sub-spectra must be introduced into models and into detection algorithms. We propose a new algorithm for detection, called group positive RIVAL, that encourages the selection of groups of sub-spectra rather than the selection of individual sub-spectra that may be from the same parent isotope. Indeed, the proposed algorithm incorporates group positive LASSO, and, as such, we supply the consistency results of group positive LASSO and adaptive group positive LASSO. In an example employing various shielding materials and material thicknesses, group positive RIVAL is shown to perform well in all scenarios with the exception of ones in which the shielding material is lead. - Highlights: ► Identification of nuclides from weak and poorly resolved spectra. ► Shielding materials such as carbon, water, concrete, and lead are considered. ► Isotope spectra are decomposed into their sub-spectra. ► A variable selection algorithm is proposed that encourages group selection. ► Simulations demonstrate the proposed method's performance when nuclides have been shielded

Chromosomal location of traits associated with wheat seedling water and phosphorus use efficiency under different water and phosphorus stresses.

Science.gov (United States)

Cao, Hong-Xing; Zhang, Zheng-Bin; Sun, Cheng-Xu; Shao, Hong-Bo; Song, Wei-Yi; Xu, Ping

2009-09-18

The objective of this study was to locate chromosomes for improving water and phosphorus-deficiency tolerance of wheat at the seedling stage. A set of Chinese Spring-Egyptian Red wheat substitution lines and their parent Chinese Spring (recipient) and Egyptian Red (donor) cultivars were measured to determine the chromosomal locations of genes controlling water use efficiency (WUE) and phosphorus use efficiency (PUE) under different water and phosphorus conditions. The results underlined that chromosomes 1A, 7A, 7B, and 3A showed higher leaf water use efficiency (WUE(l) = Pn/Tr; Pn = photosynthetic rate; Tr = transpiration rate) under W-P (Hoagland solution with 1/2P), -W-P (Hoagland solution with 1/2P and 10% PEG). Chromosomes 7A, 3D, 2B, 3B, and 4B may carry genes for positive effects on individual plant water use efficiency (WUE(p) = biomass/TWC; TWC = total water consumption) under WP (Hoagland solution), W-P and -W-P treatment. Chromosomes 7A and 7D carry genes for PUE enhancement under WP, -WP (Hoagland solution with 10% PEG) and W-P treatment. Chromosome 7A possibly has genes for controlling WUE and PUE simultaneously, which indicates that WUE and PUE may share the same genetic background. Phenotypic and genetic analysis of the investigated traits showed that photosynthetic rate (Pn) and transpiration rate (Tr), Tr and WUE(l) showed significant positive and negative correlations under WP, W-P, -WP and -W-P, W-P, -WP treatments, respectively. Dry mass (DM), WUE(P), PUT (phosphorus uptake) all showed significant positive correlation under WP, W-P and -WP treatment. PUE and phosphorus uptake (PUT = P uptake per plant) showed significant negative correlation under the four treatments. The results might provide useful information for improving WUE and PUE in wheat genetics.

Chromosomal Location of Traits Associated with Wheat Seedling Water and Phosphorus Use Efficiency under Different Water and Phosphorus Stresses

Directory of Open Access Journals (Sweden)

Wei-Yi Song

2009-09-01

Full Text Available The objective of this study was to locate chromosomes for improving water and phosphorus-deficiency tolerance of wheat at the seedling stage. A set of Chinese Spring- Egyptian Red wheat substitution lines and their parent Chinese Spring (recipient and Egyptian Red (donor cultivars were measured to determine the chromosomal locations of genes controlling water use efficiency (WUE and phosphorus use efficiency (PUE under different water and phosphorus conditions. The results underlined that chromosomes 1A, 7A, 7B, and 3A showed higher leaf water use efficiency (WUEl = Pn/Tr; Pn = photosynthetic rate; Tr = transpiration rate under W-P (Hoagland solution with1/2P, -W-P (Hoagland solution with 1/2P and 10% PEG. Chromosomes 7A, 3D, 2B, 3B, and 4B may carry genes for positive effects on individual plant water use efficiency (WUEp = biomass/TWC; TWC = total water consumption under WP (Hoagland solution, W-P and -W-P treatment. Chromosomes 7A and 7D carry genes for PUE enhancement under WP, -WP (Hoagland solution with 10% PEG and W-P treatment. Chromosome 7A possibly has genes for controlling WUE and PUE simultaneously, which indicates that WUE and PUE may share the same genetic background. Phenotypic and genetic analysis of the investigated traits showed that photosynthetic rate (Pn and transpiration rate (Tr, Tr and WUEl showed significant positive and negative correlations under WP, W-P, -WP and -W-P, W-P, -WP treatments, respectively. Dry mass (DM, WUEP, PUT (phosphorus uptake all showed significant positive correlation under WP, W-P and -WP treatment. PUE and phosphorus uptake (PUT = P uptake per plant showed significant negative correlation under the four treatments. The results might provide useful information for improving WUE and PUE in wheat genetics.

Transforming Growth Factor ß Recruits Persistent MAPK Signaling to Regulate Long-Term Memory Consolidation in "Aplysia Californica"

Science.gov (United States)

Shobe, Justin; Philips, Gary T.; Carew, Thomas J.

2016-01-01

In this study, we explore the mechanistic relationship between growth factor signaling and kinase activity that supports the protein synthesis-dependent phase of long-term memory (LTM) consolidation for sensitization of "Aplysia." Specifically, we examine LTM for tail shock-induced sensitization of the tail-elicited siphon withdrawal…

78 FR 50340 - Travelers' Information Stations

Science.gov (United States)

2013-08-19

... conveyed through advertising.'' Some broadcasters contended that this would siphon off advertising revenues...-emergency, non-travel-related information would dilute the effectiveness of TIS in assisting travelers and... the field strength of TIS stations may ``not exceed 2 mV/m when measured with a standard strength...

The filtering of raw water with partition system in pool row water for the process

International Nuclear Information System (INIS)

Harahap, Sentot Alibasya; Djunaidi

2003-01-01

The purpose of filtering raw water in the pool is decreasing soluble dirty in the water from Puspiptek PAM also the dirty from the environments. The monitoring of raw water since 1998 that the raw water is not so good in the quality. This partition system use tree type of screen a.i. the opened 10 mm, Mesh 60 and Mesh 100. The down position use a plat with 400 mm higher from the floor of the pool that given support frame from the L profile and strip plate by stainless steel (SS-304), use for deposited the impurities. The filter capability from the monitoring that the filtering result is a good quality, the TDS drop (Total Dissolved Solvent) is 2,5 gram/liter and the water filtering static type is (4 - 8,5) gram/liter

Solar water lifter

Energy Technology Data Exchange (ETDEWEB)

Khandurdyyev, A; Daykhanov, S; Itayev, K I; Kurbanov, N

1982-01-01

A water lifter is described which contains a diaphram pump with working cavity and inlet and outlet valves and solar energy collector filled with easily boiling fluid. In order to improve the degree of use of the solar energy and output, the water lifter additionally contains a bellows arranged in the working cavity of the pump and connected to it and the collector, and a cylinder made of magnetic-soft material with a magnetic valve arranged in it with a rod connected to the bellows, a seat for the valve on the upper end and contact plate interacting with the valve in its lower position.

Managing Water Sustainability: Virtual Water Flows and Economic Water Productivity Assessment of the Wine Trade between Italy and the Balkans

Directory of Open Access Journals (Sweden)

Pier Paolo Miglietta

2018-02-01

Full Text Available The management of natural resources in economic activities has become a fundamental issue when considering the perspective of sustainable development. It is necessary to rethink every process in order to reach efficiency from different points of view, not only environmentally but also economically. Water scarcity is growing because of economic and population growth, climate change, and the increasing water demand. Currently, agri-food represents the most water consumptive sector, and the increasing importance of international trade in this industry puts freshwater issues in a global context that should be analyzed and regulated by sustainable policies. This analysis is focused on virtual water flows and economic water productivity related to the wine trade, and aims to evaluate water loss/savings achieved through bilateral trade relations. The choice fell on Italy, the first wine producer in the world, and the Balkan countries. The latter are new markets for wine production/consumption, in which Italian wines are strongly positioned for different reasons. The results show that, from a national point of view and considering wine trade, Italy exports water in virtual form to the Balkan countries, more than it imports, so that in effect it partially uses its own water resources for the wine supply of the Balkans. The latter, on the other hand, being a net importer of wine, partially depends on Italian water resources and exerts less pressure on their own water basins in the supporting wine supply. We also observed that the wine trade between Italy and the Balkans implies global water savings.

Positive Technologies for Understanding and Promoting Positive Emotions.

Science.gov (United States)

Baños, Rosa María; Carrillo, Alba; Etchemendy, Ernestina; Botella, Cristina

2017-10-26

Information and Communication Technologies (ICTs) have become increasingly present in our lives, and their use has spread considerably. This paper presents a review of the way ICTs can help practitioners and researchers to study, promote, and train positive emotions. It is framed within the field of Positive Technologies: the applied scientific approach to the study of the use of technology to improve the quality of personal experience, with the goal of increasing wellbeing. First, the article presents an introduction to the topic of technologies and positive emotions. Then, it describes how ICTs can aid in monitoring, assessing, promoting, modifying, and training positive emotions. Finally, implications and future directions of the role of Positive Technologies in positive emotions are discussed. The authors conclude that, in the near future, Positive Technologies and the field of positive emotions will interact synergistically, producing an exponential growth in the understanding and promotion of positive emotions.

[Detection of Cryptospordium spp. in environmental water samples by FTA-PCR].

Science.gov (United States)

Zhang, Xiao-Ping; Zhu, Qian; He, Yan-Yan; Jiang, Li; Jiang, Shou-Fu

2011-02-01

To establish a FTA-polymeras chain reaction (FTA-PCR) method in detection of Cryptospordium spp. in different sources of water. The semi automated immunomagnetic separation (IMS) of Cryptospordium oocysts in environmental water samples was performed firstly, and then genomic DNA of Cryptospordium oocysts was extracted by FTA filters disk. Oligonucleotide primers were designed based on the DNA fragment of the 18 S rRNA gene from C. parvum. Plate DNA was amplified with primers in PCR. The control DNA samples from Toxoplasma gondii,Sarcocystis suihominis, Echinococcus granulosus, and Clonorchis sinensis were amplified simultaneously. All PCR products were detected by agar electrophoresis dyed with ethidium bromide. The 446 bp fragment of DNA was detected in all samples of C. parvum, C. andersoni, and C. baileyi, while it was not detected in control groups in laboratory. No positive samples were found from 10 samples collected from tape water in 5 districts of Shanghai City by FTA-PCR. Nine positive samples were detected totally from 70 different environmental water samples, there were 0 out of 15 samples from the source of tape water, 2 out of 25 from the Huangpu River, 5 out of 15 from rivers around the animal farmers, 1 out of 9 from output water of contaminating water treatment factory, 1 out of 6 from the out gate of living contaminating water. The 446 bp fragment was detected from all the amplified positive water samples. FTA-PCR is an efficient method for gene detection of Cryptospordium oocysts, which could be used in detection of environmental water samples. The contamination degree of Cryptospordium oocysts in the river water around animal farms is high.

Using wintergreen oil for mounting mosquito larvae: a safer alternative to xylene.

Science.gov (United States)

Koay, J B; Natasya, N N; Nashithatul, Mag; Ihsanuddin, R; Salleh, F M; Azil, A H

2016-01-01

Permanent mounting of fourth instar mosquito larvae is essential for identifying Aedes spp. This procedure requires extensive exposure to xylene, a clearing agent in the mounting process. We investigated wintergreen oil as a substitute for xylene. Five hundred larvae were mounted on slides to evaluate shrinkage or expansion of specimens after clearing using xylene or wintergreen oil. We examined the ventral brush and siphonal hair tufts for species identification and for preservation of morphological characteristics after clearing specimens in xylene or wintergreen oil. Shrinkage of the length of whole larvae and width of the head, thorax and abdomen after mounting was significantly greater after clearing with xylene than with wintergreen oil. The length of the comb scale nearest the ventral brush was similar for both clearing agents. The clarity of the specimens after mounting was improved by clearing with wintergreen oil, but the integrity of the ventral brush and siphonal hair tufts were similar for both clearing agents.

Feeding habits of whitemouth croaker Micropogonias furnieri (Perciformes: Sciaenidae in Caraguatatuba Bay, southeastern Brazil

Directory of Open Access Journals (Sweden)

Márcia Regina Denadai

2015-06-01

Full Text Available Abstract This study examined the feeding habits of Micropogonias furnieri in Caraguatatuba Bay. Samples were collected monthly between May 2003 and October 2004 by trawling in two areas (southern and northern parts of the bay. The fish were measured and their stomach contents identified. The abundance was compared between areas and among months. M. furnieri was more abundant in the southern area and in the spring of 2003. The population was dominated by small immature individuals. This species had a varied diet, feeding on crustaceans, bivalve siphons, and polychaetes. The ingestion of bivalve siphons may be an opportunistic behavior, due to the presence of a large bank of the bivalve Tivela mactroides in the study area. The high proportion of unidentified organic matter in the stomach corroborates published reports that this species eats continuously and has rapid digestion. These results demonstrate that M. furnieri can be considered a carnivore, with a preference for benthic organisms.

Videoradiography of free jejunal grafts for rehabilitation of speech in laryngectomized patients

International Nuclear Information System (INIS)

Pokieser, P.; Grasl, M.C.; Schima, W.; Uranitsch, K.; Piza-Katzer, H.; Niederle, B.; Ehrenberger, K.; Ekberg, O.; Tscholakoff, D.

1995-01-01

In laryngectomized patients a tracheo-esophageal artificial fistula can be used to achieve air flow from the trachea to the esophagus during speech. A one-way plastic valve is often used for the fistula. A free jejunal graft between the trachea and the esophagus can also be used. To avoid aspiration the transplant is attached to the submental area giving the graft a siphon-like shape. We performed 23 videoradiographic examinations using high-density barium in 14 such patients. The aim was to evaluate the protective function of these grafts against aspiration. Penetration of the bolus and a small amount of residual contrast material in the ascending limb of the graft was a normal finding. If the standard barium bolus reached the descending limb at any time during the examination, this was a sign of aspiration hazard. To avoid aspiration, the vertex of the speech siphon should be higher than the level of the hypopharyngeal anastomosis. (orig.)

Water-controlled wealth of nations.

Science.gov (United States)

Suweis, Samir; Rinaldo, Andrea; Maritan, Amos; D'Odorico, Paolo

2013-03-12

Population growth is in general constrained by food production, which in turn depends on the access to water resources. At a country level, some populations use more water than they control because of their ability to import food and the virtual water required for its production. Here, we investigate the dependence of demographic growth on available water resources for exporting and importing nations. By quantifying the carrying capacity of nations on the basis of calculations of the virtual water available through the food trade network, we point to the existence of a global water unbalance. We suggest that current export rates will not be maintained and consequently we question the long-term sustainability of the food trade system as a whole. Water-rich regions are likely to soon reduce the amount of virtual water they export, thus leaving import-dependent regions without enough water to sustain their populations. We also investigate the potential impact of possible scenarios that might mitigate these effects through (i) cooperative interactions among nations whereby water-rich countries maintain a tiny fraction of their food production available for export, (ii) changes in consumption patterns, and (iii) a positive feedback between demographic growth and technological innovations. We find that these strategies may indeed reduce the vulnerability of water-controlled societies.

Position calibration for the future KM3NeT detector

International Nuclear Information System (INIS)

Motz, Holger

2010-01-01

Deep-sea neutrino telescopes consist of an array of photomultipliers to detect Cherenkov light emitted by neutrino-induced muons and particle showers in the surrounding sea water, allowing for reconstruction of the neutrino direction from position and timing of the Cherenkov photons. Since the photomultipliers are in most cases mounted on flexible structures, e.g. lines, and move with the sea current, a positioning system is required to determine the precise location of each sensor. The positioning system of the ANTARES neutrino telescope is based on acoustic triangulation using hydrophones mounted along the lines in combination with tiltmeters and compasses and provides centimetre precision alignment. For the future KM3NeT detector an Optical Module with integrated Piezo sensors for position calibration is proposed as a cost-effective solution. The performance of this system is tested with several sensors of the AMADEUS project, which is integrated in ANTARES to study the background for acoustic detection of highest energy neutrinos.

A direct method for determining complete positive and negative capillary pressure curves for reservoir rock using the centrifuge

Energy Technology Data Exchange (ETDEWEB)

Spinler, E.A.; Baldwin, B.A. [Phillips Petroleum Co., Bartlesville, OK (United States)

1997-08-01

A method is being developed for direct experimental determination of capillary pressure curves from saturation distributions produced during centrifuging fluids in a rock plug. A free water level is positioned along the length of the plugs to enable simultaneous determination of both positive and negative capillary pressures. Octadecane as the oil phase is solidified by temperature reduction while centrifuging to prevent fluid redistribution upon removal from the centrifuge. The water saturation is then measured via magnetic resonance imaging. The saturation profile within the plug and the calculation of pressures for each point of the saturation profile allows for a complete capillary pressure curve to be determined from one experiment. Centrifuging under oil with a free water level into a 100 percent water saturated plug results in the development of a primary drainage capillary pressure curve. Centrifuging similarly at an initial water saturation in the plug results in the development of an imbibition capillary pressure curve. Examples of these measurements are presented for Berea sandstone and chalk rocks.

On truncated Taylor series and the position of their spurious zeros

DEFF Research Database (Denmark)

Christiansen, Søren; Madsen, Per A.

2006-01-01

A truncated Taylor series, or a Taylor polynomial, which may appear when treating the motion of gravity water waves, is obtained by truncating an infinite Taylor series for a complex, analytical function. For such a polynomial the position of the complex zeros is considered in case the Taylor...

hydrogeochemistry and quality assessment of some ground water ...

African Journals Online (AJOL)

PROF EKWUEME

Waters adversely affected by abnormal concentration of iron tend ... is a reflection of the tectonic and geologic events that occurred over the .... PLATE COUNT. COLONIES. REMARKS. Ninth Mile Corner. Boreholes: Untreated. 70. Positive. 4 colonies after. 24hrs at 370c. Suspicious. Udi water supply. Untreated borehole. 3.

Water balance of goats in Jeneponto - South Sulawesi under sunlight exposure and water restriction

Directory of Open Access Journals (Sweden)

Djoni Prawira Rahardja

2007-10-01

Full Text Available Water balance of 5 does of Kacang goat of Jeneponto was studied under the condition of sunlight exposure and water restriction. The study was conducted in dry season with 4 consecutive treatments of 10 d with 4-5 d of adjustment period between two consecutive treatments: (1 indoor and unrestricted water; (2 indoor and restricted water; (3 10 h outdoor–and unrestricted water; (4 10 h outdoor – restricted water. The maximum air temperature of outdoor was 39.3OC, and it was 30OC in the indoor environment. In all treatments, the animals were placed in the individual crates. The plasma volume of the goats was higher under sunlight exposure, but it decreased by water restriction, while hematocrite value indicated a reverse responses. Sunlight exposure did not significantly decrease the intake and digestion of organic matter, but water restriction affected significantly and this effect was higher under sunlight exposre. The proportions of water loss through every avenue were maintained relatively constant either under water restriction or sunlight exposure in which the respration rate increased significantly. The findings suggest that sunlight exposure with unrestricted water resulted in a positive water balance without a significant change in organic matter intake and utilization. Water restriction resulted in a negative water balance, reducing organic matter intake and utilization. As the adaptive mechanisms, the goat appeared to be able to withstand in the harsh environment of Jeneponto by expanding plasma volume, increasing body temperature and respiration rate.

Modulation of pumping rate by two species of marine bivalve molluscs in response to neurotransmitters: Comparison of in vitro and in vivo results.

Science.gov (United States)

Frank, Dana M; Deaton, Lewis; Shumway, Sandra E; Holohan, Bridget A; Ward, J Evan

2015-07-01

Most studies regarding the neuroanatomy and neurophysiology of molluscan ctenidia have focused on isolated ctenidial tissue preparations. This study investigated how bivalve molluscs modulate their feeding rates by examining the effects of a variety of neurotransmitters, including serotonin, dopamine, and the dopamine agonist apomorphine on both isolated ctenidial tissue and in intact members of two commercially important bivalve species: the blue mussel, Mytilus edulis; and the bay scallop Argopecten irradians. In particular, we examined the effect of changes in: 1) beat of the lateral cilia (in vitro), 2) distance between ctenidial filaments and/or plicae (in vivo), and 3) diameter of the siphonal openings (in vivo) on alteration of bulk water flow through the mantle cavity. Important differences were found between isolated tissue and whole animals, and between species. Drugs that stimulated ciliary beat in vitro did not increase water processing rate in vivo. None of the treatments increased water flow through the mantle cavity of intact animals. Results suggest that A. irradians was primarily modulating lateral ciliary activity, while M. edulis appeared to have a number of ways to control water processing activity, signifying that the two species may have different compensatory and regulatory mechanisms controlling feeding activity. Copyright © 2015 Elsevier Inc. All rights reserved.

Pedotransfer functions to estimate soil water content at field capacity ...

Indian Academy of Sciences (India)

20

Soil water retention, Dry lands, Western India, Pedotransfer functions, Soil moisture calculator. 1. 2. 3. 4 ..... samples although it is known that structure and macro-porosity of the sample affect water retention (Unger ..... and OC content has positive influence on water retention whereas interaction of clay and OC has negative ...

Water-deficit tolerant classification in mutant lines of indica rice

Directory of Open Access Journals (Sweden)

Suriyan Cha-um

2012-04-01

Full Text Available Water shortage is a major abiotic stress for crop production worldwide, limiting the productivity of crop species, especially in dry-land agricultural areas. This investigation aimed to classify the water-deficit tolerance in mutant rice (Oryza sativa L. spp. indica genotypes during the reproductive stage. Proline content in the flag leaf of mutant lines increased when plants were subjected to water deficit. Relative water content (RWC in the flag leaf of different mutant lines dropped in relation to water deficit stress. A decrease RWC was positively related to chlorophyll a degradation. Chlorophyll a , chlorophyll b , total chlorophyll , total carotenoids , maximum quantum yield of PSII , stomatal conductance , transpiration rate and water use efficiency in mutant lines grown under water deficit conditions declined in comparison to the well-watered, leading to a reduction in net-photosynthetic rate. In addition, when exposed to water deficit, panicle traits, including panicle length and fertile grains were dropped. The biochemical and physiological data were subjected to classify the water deficit tolerance. NSG19 (positive control and DD14 were identified as water deficit tolerant, and AA11, AA12, AA16, BB13, BB16, CC12, CC15, EE12, FF15, FF17, G11 and IR20 (negative control as water deficit sensitive, using Ward's method.

Trend of Legionella colonization in hospital water supply.

Science.gov (United States)

D'Alessandro, D; Fabiani, M; Cerquetani, F; Orsi, G B

2015-01-01

In many nosocomial Legionella outbreaks water distribution systems are the most frequent source of infection. Considering the hospital waterline old age, an investigation on colonization by Legionella spp was carried out in order to evaluate the pipeline system weaknesses and to implement environmental preventive measures. From 2004 to 2010, overall 97 samples from the water line were collected. The samples were analyzed according to the italian Legionella spp standard methods; water temperature, pH and residual free chlorine were determined at the time of collection. X2 test, exact-test and t-test were used to compare proportions and means. Overall 28 samples (23.7%) were positive for Legionella spp, and five of them (17.9%) exceeded the threshold level >104 cfu/L. The number of positive samples varied along the years, showing a significant increasing trend (X2 for trend = 11.5; pLegionella spp by comparison to negative ones showed a lower free chlorine concentration (0.08 mg/L vs 0.15 mg/L) and a higher water temperature (46.1° vs 42.7°). Actually the percentage of positive samples decreased significantly with the increasing in free chlorine in the water (X2 for trend = 8.53; pLegionella. All hospital buildings were colonized by Legionella spp, although 80% of samples >104 cfu/L occurred in the C-building. No cases of nosocomial legionellosis were reported during the study period. Hospital water system showed a diffuse colonization by Legionella spp, although the degree of contamination reached the threshold level (>104 cfu/L) only in a small percentage of samples, showing a substantial effectiveness of the control measures applied.

Position displacement effect on the doses in the peripheral head regions

International Nuclear Information System (INIS)

Kortesniemi, M.; Seppaelae, T.; Bjugg, H.; Seren, T.; Kotiluoto, P.; Auterinen, I.; Parkkinen, R.; Savolainen, S.

2000-01-01

Patient positioning is a challenging task in BNCT-treatments due to the use of multiple fields and a static horizontal beam construction. Positioning accuracy of 5 mm is required for acceptable dose delivery within appropriate limits of dose uncertainty (up to 10% of point dose in target volume). The aim of this study was to determine if a patient head position creating a clear gap between the beam port and the head would have a significant effect on the doses to the peripheral regions of the head, e.g. to the eyes. The gamma dose rates were measured in a water filled ellipsoidal phantom with an ionisation chamber (IC). Mn activation wires were used to determine the Mn-55(n, γ) reaction rates. Twelve measurement points were chosen in the phantom and two phantom positions were applied. According to this study the 35 mm position change and the resulting gap has an obvious effect on the peripheral doses in BNCT. The Mn activation reaction rates were on the average 80% higher in the deviation position than in the reference position. Increasing depth from the surface inside the phantom diminished the gamma dose difference between the two positions. Scattering environment changes with position displacement and resulting gap causes differences in neutron fluences and gamma doses. (author)

Detection by PCR of pathogenic protozoa in raw and drinkable water samples in Colombia.

Science.gov (United States)

Triviño-Valencia, Jessica; Lora, Fabiana; Zuluaga, Juan David; Gomez-Marin, Jorge E

2016-05-01

We evaluated the presence of DNA of Giardia, Toxoplasma, and Cryptosporidium by PCR, and of Giardia and Cryptosporidium genera by immunofluorescence antibody test (IFAT), in water samples, before, during, and after plant treatment for drinkable water. We applied this method in 38 samples of 10 l of water taken from each of the water treatment steps and in 8 samples taken at home (only for Toxoplasma PCR) in Quindio region in Colombia. There were 8 positive samples for Cryptosporidium parvum (21 %), 4 for Cryptosporidium hominis (10.5 %), 27 for Toxoplasma gondii (58.6 %), 2 for Giardia duodenalis assemblage A (5.2 %), and 5 for G. duodenalis assemblage B (13.1 %). By IFAT, 23 % were positive for Giardia and 21 % for Cryptosporidium. An almost perfect agreement was found between IFAT and combined results of PCR, by Kappa composite proportion analysis. PCR positive samples were significantly more frequent in untreated raw water for C. parvum (p = 0.02). High mean of fecal coliforms, high pH values, and low mean of chlorine residuals were strongly correlated with PCR positivity for G. duodenalis assemblage B. High pH value was correlated with PCR positivity for C. parvum. Phylogenetic analysis of DNA sequences was possible, showing water and human clinical sequences for Toxoplasma within the same phylogenetic group for B1 repeated sequence. PCR assay is complementary to IFAT assay for monitoring of protozoa in raw and drinkable water, enabling species identification and to look for phylogenetic analysis in protozoa from human and environmental sources.

Timing of warm water refuge use in Crystal River National Wildlife Refuge by manatees—Results and insights from Global Positioning System telemetry data

Science.gov (United States)

Slone, Daniel H.; Butler, Susan M.; Reid, James P.; Haase, Catherine G.

2017-11-21

Managers at the U.S. Fish and Wildlife Service Crystal River National Wildlife Refuge (CRNWR) desire to update their management plan regarding the operation of select springs including Three Sisters Springs. They wish to refine existing parameters used to predict the presence of federally threatened Trichechus manatus latirostris (Florida manatee) in the springs and thereby improve their manatee management options. The U.S. Geological Survey Sirenia Project has been tracking manatees in the CRNWR area since 2006 with floating Global Positioning System (GPS) satellite-monitored telemetry tags. Analyzing movements of these tagged manatees will provide valuable insight into their habitat use patterns.A total of 136 GPS telemetry bouts were available for this project, representing 730,009 locations generated from 40 manatees tagged in the Gulf of Mexico north of Tampa, Florida. Dates from October through March were included to correspond to the times that cold ambient temperatures were expected, thus requiring a need for manatee thermoregulation and a physiologic need for warm water. Water level (tide) and water temperatures were obtained for the study from Salt River, Crystal River mouth, Bagley Cove, Kings Bay mouth, and Magnolia Spring. Polygons were drawn to subdivide the manatee locations into areas around the most-used springs (Three Sisters/Idiots Delight, House/Hunter/Jurassic, Magnolia and King), Kings Bay, Crystal/Salt Rivers and the Gulf of Mexico.Manatees were found in the Crystal or Salt Rivers or in the Gulf of Mexico when ambient temperatures were warmer (>20 °C), while they were found in or near the springs (especially Three Sisters Springs) at colder ambient water temperatures. There was a trend of manatees entering springs early in the morning and leaving in the afternoon. There was a strong association of manatee movements in and out of the Three Sisters/Idiots Delight polygon with tide cycles: manatees were more likely to enter the Three Sisters

Numerical analysis of the fluid dynamics in a natural circulation loop

International Nuclear Information System (INIS)

Angelo, Gabriel

2013-01-01

Natural circulation loops apply to many engineering applications such as: water heating solar energy system (thermo-siphons), thermal management of electrical components (voltage converter), geothermal energy, nuclear reactors, etc. In pressurized water nuclear reactors, known as PWR's, the natural circulation loops are employed to ensure passive safety. In critical situations, the heat transfer will occur only by natural convection, without any external control or mechanical devices. This feature is desired and has been considered in modern nuclear reactor projects. This work consists of a numerical study of the natural circulation loop, located at the Instituto de Pesquisas Energeticas e Nucleares / Comissao Nacional de Energia Nuclear in Sao Paulo, Brazil, in order to establish the flow pattern in single phase conditions. The comparison of numerical results to experiments in transient condition revealed significant deviations for the Zero Equation turbulence model. Intermediate deviations for the Eddy Viscosity Turbulence Equation (EVTE), k - ω, SST e SSG models. And the best results are obtained by the k - ε e DES models (with better results for the k - ε model). (author)

Numerical analysis of the fluid dynamics in a natural circulation loop; Analise numerica da dinamica do escoamento em circuitos de circulacao natural

Energy Technology Data Exchange (ETDEWEB)

Angelo, Gabriel

2013-07-01

Natural circulation loops apply to many engineering applications such as: water heating solar energy system (thermo-siphons), thermal management of electrical components (voltage converter), geothermal energy, nuclear reactors, etc. In pressurized water nuclear reactors, known as PWR's, the natural circulation loops are employed to ensure passive safety. In critical situations, the heat transfer will occur only by natural convection, without any external control or mechanical devices. This feature is desired and has been considered in modern nuclear reactor projects. This work consists of a numerical study of the natural circulation loop, located at the Instituto de Pesquisas Energeticas e Nucleares / Comissao Nacional de Energia Nuclear in Sao Paulo, Brazil, in order to establish the flow pattern in single phase conditions. The comparison of numerical results to experiments in transient condition revealed significant deviations for the Zero Equation turbulence model. Intermediate deviations for the Eddy Viscosity Turbulence Equation (EVTE), k - {omega}, SST e SSG models. And the best results are obtained by the k - {epsilon} e DES models (with better results for the k - {epsilon} model). (author)

Are positive emotions just as "positive" across cultures?

Science.gov (United States)

Leu, Janxin; Wang, Jennifer; Koo, Kelly

2011-08-01

Whereas positive emotions and feeling unequivocally good may be at the heart of well-being among Westerners, positive emotions often carry negative associations within many Asian cultures. Based on a review of East-West cultural differences in dialectical emotions, or co-occurring positive and negative feelings, we predicted culture to influence the association between positive emotions and depression, but not the association between negative emotions and depression. As predicted, in a survey of over 600 European-, immigrant Asian-, and Asian American college students, positive emotions were associated with depression symptoms among European Americans and Asian Americans, but not immigrant Asians. Negative emotions were associated with depression symptoms among all three groups. We also found initial evidence that acculturation (i.e., nativity) may influence the role of positive emotions in depression: Asian Americans fell "in between" the two other groups. These findings suggest the importance of studying the role of culture in positive emotions and in positive psychology. The use of interventions based on promoting positive emotions in clinical psychology among Asian clients is briefly discussed. 2011 APA, all rights reserved

Numerical simulation and structural optimization of the inclined oil/water separator.

Directory of Open Access Journals (Sweden)

Liqiong Chen

Full Text Available Improving the separation efficiency of the inclined oil/water separator, a new type of gravity separation equipment, is of great importance. In order to obtain a comprehensive understanding of the internal flow field of the separation process of oil and water within this separator, a numerical simulation based on Euler multiphase flow analysis and the realizable k-ε two equation turbulence model was executed using Fluent software. The optimal value ranges of the separator's various structural parameters used in the numerical simulation were selected through orthogonal array experiments. A field experiment on the separator was conducted with optimized structural parameters in order to validate the reliability of the numerical simulation results. The research results indicated that the horizontal position of the dispenser, the hole number, and the diameter had significant effects on the oil/water separation efficiency, and that the longitudinal position of the dispenser and the position of the weir plate had insignificant effects on the oil/water separation efficiency. The optimal structural parameters obtained through the orthogonal array experiments resulted in an oil/water separation efficiency of up to 95%, which was 4.996% greater than that realized by the original structural parameters.

Economics of selected water control technologies and their ...

African Journals Online (AJOL)

Using a production function, marginal productivity of farm inputs and benefit-cost analysis, we explore the economics of selected water control technologies. From the production function, all farm inputs, including irrigation water is found to have a significant and positive effect on yield. Marginal value products of farm inputs ...

Density and volume measurements of reprocessing plant feed

International Nuclear Information System (INIS)

Platzer, R.; Carrier, M.; Neuilly, M.; Dedaldechamp, P.

1985-05-01

A theoretical study of the phenomenon of gas bubbles formation within a liquid led to an adaptation of the differential pressure bubbling technique for the measurement of liquid levels and densities in tanks. Experiments, carried out on a 800 liters tank with water and uranyl nitrate solutions had the double aim to study the precision attainable on volume and density measurements and to design a method for corrections of influencing factors. In parallel, procedures for transfer of known volumes through the use of siphons and for tank calibration by liquid level measurement are also investigated. The paper presents the first results obtained so far and the conclusions to be drawn for the elaboration of calibration and exploitation procedures suitables for use in reprocessing plants. The demonstration to transfer mass of solution with an accuracy of 0.1% is made [fr

Magnitude, spatial scale and optimization of ecosystem services from a nutrient extraction mussel farm in the eutrophic Skive Fjord, Denmark

DEFF Research Database (Denmark)

Nielsen, Pernille; Cranford, P. J.; Maar, M.

2016-01-01

Suspended mussel aquaculture has been proposed as a possible mechanism by which to remove excess nutrients from eutrophic marine areas. In this study, seasonal mussel growth and water clarification (through seston and phytoplankton depletion) were studied at a commercial-scale nutrient extractive...... mussel farm in a highly eu - trophic Danish fjord. Spatial variations in mussel biomass were examined throughout the year and no significant differences were detected within the farm. Food depletion by mussels was examined at spatial scales ranging from individuals to the entire farm and surrounding area....... Phytoplankton depletion on the scale of individual mussel loops, determined using the siphon mimic approach, indicated between 27 and 44% depletion of chlorophyll a (chl a). Farm-scale depletion was detected and visualized based on intensive 3D spatial surveys of the distribution of chl a and total suspended...

Flat Top Barge 300 feet Using Portable Dynamic Positioning System

Directory of Open Access Journals (Sweden)

Agoes Santoso

2017-03-01

Full Text Available Portable Dynamic Positioning System has not commonly applied to the ship, especially on barge. Besides for Dynamic Positioning function, the system can be used as ship's main propulsion. By using this system, the ship able to not using anchors because the functions can be performed by the Portable Dynamic System. Therefore, research about the application of Portable Dynamic Positioning System on the ship is conducted. This research aims to design a Flat Top Barge 300feet ship, to determine the specifications of Portable Dynamic Positioning System which is used, and to find out the ship stability which is designed on the empty payload condition and maximum payload. This research designed the ships with main dimensions LWL 90.1 meters, 25 meters wide, 5.5 meters high and 4.2 meters draught. To generate the ship with a maximum speed of 8 knots, it takes four thruster supplied with power 225 kW each, so that the total generated power is 1100 kW. This study analyzes three conditions of the ship stability, there are the condition of full payload, empty payload, and maximum payload. Each payload conditions will be analyzed regarding the large payload and draught water produced. The first is full payload conditions resulting payload in the amount of 5650 ton with a draught on the LCF at 4,181 meters. The second is the large empty payload condition displacement is 2809 ton and water draught on the LCF at 1,591. And the last is maximum payload conditions, resulting payload in the amount of 7450 ton with a draught on the LCF at 4,994 meters.

Correlation between octanol/water and liposome/water distribution coefficients and drug absorption of a set of pharmacologically active compounds.

Science.gov (United States)

Esteves, Freddy; Moutinho, Carla; Matos, Carla

2013-06-01

Absorption and consequent therapeutic action are key issues in the development of new drugs by the pharmaceutical industry. In this sense, different models can be used to simulate biological membranes to predict the absorption of a drug. This work compared the octanol/water and the liposome/water models. The parameters used to relate the two models were the distribution coefficients between liposomes and water and octanol and water and the fraction of drug orally absorbed. For this study, 66 drugs were collected from literature sources and divided into four groups according to charge and ionization degree: neutral; positively charged; negatively charged; and partially ionized/zwitterionic. The results show a satisfactory linear correlation between the octanol and liposome systems for the neutral (R²= 0.9324) and partially ionized compounds (R²= 0.9367), contrary to the positive (R²= 0.4684) and negatively charged compounds (R²= 0.1487). In the case of neutral drugs, results were similar in both models because of the high fraction orally absorbed. However, for the charged drugs (positively, negatively, and partially ionized/zwitterionic), the liposomal model has a more-appropriate correlation with absorption than the octanol model. These results show that the neutral compounds only interact with membranes through hydrophobic bonds, whereas charged drugs favor electrostatic interactions established with the liposomes. With this work, we concluded that liposomes may be a more-appropriate biomembrane model than octanol for charged compounds.

Detecting positive quadrant dependence and positive function dependence

NARCIS (Netherlands)

Janic-Wróblewska, A.; Kallenberg, W.C.M.; Ledwina, T.

2004-01-01

There is a lot of interest in positive dependence going beyond linear correlation. In this paper three new rank tests for testing independence against positive dependence are introduced. The first one is directed on positive quadrant dependence, the second and third one concentrate on positive

Detecting positive quadrant dependence and positive function dependence

NARCIS (Netherlands)

Janic-Wróblewska, A.; Kallenberg, W.C.M.; Ledwina, T.

2003-01-01

There is a lot of interest in positive dependence going beyond linear correlation. In this paper three new rank tests for testing independence against positive dependence are introduced. The first one is directed on positive quadrant dependence, the second and third one concentrate on positive

Enhancement of efficacy of process water monitors in detecting heavy water leak in steam generator blow down lines

International Nuclear Information System (INIS)

Mitra, S.R.; Kohale, S.D.; Parida, B.K.; Gathe, G.D.; Pati, C.K.; Mudgal, B.K.; Niraj; Pawar, S.K.

2006-01-01

The Steam Generator (SG) serves as an interface between primary and secondary cycle in Pressurized Heavy Water Reactor (PHWR). Failure of steam generator tubes result in leaking of active heavy water in the secondary closed loop. In Tarapur Atomic Power Station-3 and 4 (TAPS- 3 and 4), Scintillator detectors are provided to detect on line heavy water leakages in SG and moderator heat exchangers by monitoring Nitrogen-16 ( 16 N) and Oxygen-19 ( 19 O) activities. Efficacy of detection of these activities at designed detector position on SG blow down line in presence of background radiation field is analysed theoretically. The count rate of 19 O and 16 N estimated at the detector position inside Reactor Building (RB) shows that detectors only respond to very high leak rates due to presence of high ambient radiation level even though sensitivity is appreciably good. For detector position in RB in the accessible areas and out side the RE containment, the travel time for the blow down feed water becomes moderately and very long respectively resulting in poor sensitivity. However the results show that wherever background levels is low, the efficacy of leak detection becomes considerably better than the results obtained when detector is placed inside RB. The study was validated during the reactor operation by recording the detector count rates due to prevalent ambient radiation level near to the detectors. Subsequently the detectors were relocated in an area inside RB where relocation was feasible, travel time of the blow down feed water was moderate and the area had an relatively low ambient radiation level. This paper discusses the methodology adopted during the study and results obtained during theoretical estimation and practical validation. (author)

A charge-driven molecular water pump.

Science.gov (United States)

Gong, Xiaojing; Li, Jingyuan; Lu, Hangjun; Wan, Rongzheng; Li, Jichen; Hu, Jun; Fang, Haiping

2007-11-01

Understanding and controlling the transport of water across nanochannels is of great importance for designing novel molecular devices, machines and sensors and has wide applications, including the desalination of seawater. Nanopumps driven by electric or magnetic fields can transport ions and magnetic quanta, but water is charge-neutral and has no magnetic moment. On the basis of molecular dynamics simulations, we propose a design for a molecular water pump. The design uses a combination of charges positioned adjacent to a nanopore and is inspired by the structure of channels in the cellular membrane that conduct water in and out of the cell (aquaporins). The remarkable pumping ability is attributed to the charge dipole-induced ordering of water confined in the nanochannels, where water can be easily driven by external fields in a concerted fashion. These findings may provide possibilities for developing water transport devices that function without osmotic pressure or a hydrostatic pressure gradient.

Improved relationships in eastern Kenya from water interventions and access to water.

Science.gov (United States)

Zolnikov, Tara Rava; Blodgett Salafia, Elizabeth

2016-03-01

Global health interventions focus on providing solutions to unaddressed public health issues in low- and middle-income countries. Providing nearby access to safe drinking water is a primary public health concern and a frequent public health intervention throughout sub-Saharan Africa; access to water eliminates long gathering and transport time and provides an individual with more personal time. Previous research has not reviewed the aspect of time and relationship changes after implemented water interventions. A qualitative phenomenological approach used 52 semistructured interviews to examine relationship experiences among primary water gatherers and their families after receiving nearby access to water. This study took place throughout the historically semiarid eastern region in Kitui, Kenya, where community members have been beneficiaries of various water interventions. Before the water intervention, family members experienced difficulties with irregular meal times and food availability, infrequent family conversations, irritation with lack of bathing and cleanliness, and general discontent without the availability of 1 able-bodied family member. Participants' experiences after implemented water interventions revealed enhanced relationships within household family units; additional personal time was gained and used to rebuild relationships. The newly established relationships included constructive discussions and conversations built around understanding and developing solutions to address economic or individual challenges encountered by the family. This study's findings suggest that relationships significantly improved after households receive access to nearby water. Furthermore, this research provides evidence of an increased need for access to quality water for communities throughout the world to positively contribute to constructive family relationships. (c) 2016 APA, all rights reserved).

Potential uses of high gradient magnetic filtration for high-temperature water purification in boiling water reactors

International Nuclear Information System (INIS)

Elliott, H.H.; Holloway, J.H.; Abbott, D.G.

1979-01-01

Studies of various high-temperature filter devices indicate a potentially positive impact for high gradient magnetic filtration on boiling water reactor radiation level reduction. Test results on in-plant water composition and impurity crystallography are presented for several typical boiling water reactors (BWRs) on plant streams where high-temperature filtration may be particularly beneficial. An experimental model on the removal of red iron oxide (hematite) from simulated reactor water with a high gradient magnetic filter is presented, as well as the scale-up parameters used to predict the filtration efficiency on various high temperature, in-plant streams. Numerical examples are given to illustrate the crud removal potential of high gradient magnetic filters installed at alternative stream locations under typical, steady-state, plant operating conditions

Estimating the Determinants of Residential Water Demand in Italy

OpenAIRE

Giulia Romano; Nicola Salvati; Andrea Guerrini

2014-01-01

The aim of this study was to estimate the determinants of residential water demand for chief towns of every Italian province, in the period 2007–2009, using the linear mixed-effects model estimated with the restricted-maximum-likelihood method. Results confirmed that the applied tariff had a negative effect on residential water consumption and that it was a relevant driver of domestic water consumption. Moreover, income per capita had a positive effect on water consumption. Among measured cli...

Economic aspects of virtual water trade

Science.gov (United States)

Oki, Taikan; Yano, Shinjiro; Hanasaki, Naota

2017-04-01

Although water is rarely traded over long distances by itself, the total weight of the water consumed to produce traded commodities exceeds the weight of any other commodity traded in the world. This concept is known as virtual water trade. Although space-/time-/commodity-based quantification has been conducted extensively, the underlying causes of this peculiar feature have thus far received little exploration. Here, we use estimates of water consumption from a global hydrological model and statistical data related to food trade to elucidate three facts that explain the fundamental nature of virtual water trade with respect to alleviating water scarcity. First, we quantitatively illustrate the unique position of water among commodities based on its unit price and quantity of sales. Water has an extremely low unit price, and a tremendous volume of water is consumed per person each day. Second, we show that rich but water-scarce countries tend to reduce local water consumption by importing virtual water. Third, we demonstrate that nations characterized by net virtual water exports have higher water resources and income per capita and that no countries fall below a certain threshold with respect to both GDP and water resources. These points suggest that the virtual water trade is explained by economic characteristics of water and that sustainable development depends on promoting the co-development of poverty alleviation and water resource development.

Energy requirement assessed by doubly-labeled water method in patients with advanced amyotrophic lateral sclerosis managed by tracheotomy positive pressure ventilation.

Science.gov (United States)

Ichihara, Noriko; Namba, Kazuyoshi; Ishikawa-Takata, Kazuko; Sekine, Kazunori; Takase, Mitsunori; Kamada, Yuko; Fujii, Seigo

2012-10-01

This study aimed to clarify the energy requirement in patients with amyotrophic lateral sclerosis (ALS) undergoing tracheostomy positive pressure ventilation with tracheostomy. Total energy expenditure (TEE) was measured in 10 hospitalized bedridden ALS patients using the doubly-labeled water (DLW) method. The mean TEE/day and TEE/fat- free mass estimated by DLW method were 934 ± 201 kcal/day and 34.8 ± 5.5 kcal/kg/day, respectively. The mean TEE/resting metabolic rate (RMR) was 0.85 when RMR was estimated by the Harris-Benedict equation, 0.91 by Dietary Reference Intake (DRI), and 0.97 by Ganpule's equation using fat-free mass (FFM). The ratios of TEE to measured RMR were 1.05, 1.15 and 1.23 in three patients. In conclusion, multiplying measured RMR by 1.1 to 1.2 is considered to be appropriate to estimate energy need. However, because it is difficult to measure RMR directly in a clinical setting, an appropriate equation for estimating RMR for ALS patient should be developed.

Correction of Pressure Drop in Steam and Water System in Performance Test of Boiler

Science.gov (United States)

Liu, Jinglong; Zhao, Xianqiao; Hou, Fanjun; Wu, Xiaowu; Wang, Feng; Hu, Zhihong; Yang, Xinsen

2018-01-01

Steam and water pressure drop is one of the most important characteristics in the boiler performance test. As the measuring points are not in the guaranteed position and the test condition fluctuation exsits, the pressure drop test of steam and water system has the deviation of measuring point position and the deviation of test running parameter. In order to get accurate pressure drop of steam and water system, the corresponding correction should be carried out. This paper introduces the correction method of steam and water pressure drop in boiler performance test.

Peatland water repellency: Importance of soil water content, moss species, and burn severity

Science.gov (United States)

Moore, P. A.; Lukenbach, M. C.; Kettridge, N.; Petrone, R. M.; Devito, K. J.; Waddington, J. M.

2017-11-01

Wildfire is the largest disturbance affecting peatlands, with northern peat reserves expected to become more vulnerable to wildfire as climate change enhances the length and severity of the fire season. Recent research suggests that high water table positions after wildfire are critical to limit atmospheric carbon losses and enable the re-establishment of keystone peatland mosses (i.e. Sphagnum). Post-fire recovery of the moss surface in Sphagnum-feathermoss peatlands, however, has been shown to be limited where moss type and burn severity interact to result in a water repellent surface. While in situ measurements of moss water repellency in peatlands have been shown to be greater for feathermoss in both a burned and unburned state in comparison to Sphagnum moss, it is difficult to separate the effect of water content from species. Consequently, we carried out a laboratory based drying experiment where we compared the water repellency of two dominant peatland moss species, Sphagnum and feathermoss, for several burn severity classes including unburned samples. The results suggest that water repellency in moss is primarily controlled by water content, where a sharp threshold exists at gravimetric water contents (GWC) lower than ∼1.4 g g-1. While GWC is shown to be a strong predictor of water repellency, the effect is enhanced by burning. Based on soil water retention curves, we suggest that it is highly unlikely that Sphagnum will exhibit strong hydrophobic conditions under field conditions.

Effects of submerged vegetation on water clarity across climates

NARCIS (Netherlands)

Kosten, S.; Lacerot, G.; Jeppesen, E.; Motta Marques, D.M.L.; Nes, van E.H.; Mazzeo, N.; Scheffer, M.

2009-01-01

A positive feedback between submerged vegetation and water clarity forms the backbone of the alternative state theory in shallow lakes. The water clearing effect of aquatic vegetation may be caused by different physical, chemical, and biological mechanisms and has been studied mainly in temperate

Urban Water Management Considering Reclaimed Wastewater and Runoff as a New Water Resource for City of Tehran, Iran

Directory of Open Access Journals (Sweden)

Abedeh Abdolghafoorian

2012-12-01

According to this study, improving wastewater treatment plants and control of water quality in canals and streams in order to substitute these two new resource for freshwater and groundwater have positive environmental and economic effects. The examples of environmental benefits are reducing pollution loads to receiving streams, adjusting increasing water demand and preventing groundwater level drawdown especially in the period of drought. In addition to the environmental benefits, although improving wastewater treatment plants and control of water quality in canals and streams need considerable investments, long usage of these two new recourses is more worthwhile.

Survey on Heterotrophic Bacterial Contamination in Bottled Mineral Water by Culture Method

Directory of Open Access Journals (Sweden)

Essmaeel Ghorbanalinezhad

2014-12-01

Full Text Available Background and Aim: This project focuses on the level of heterotrophic baceria in bottled mineral water which could be a health concern for the elderly, infants, pregnant women and immuno-compromised patients. Materials and Methods: Different brands of bottled water samples were selected randomly and evaluated for their bacteriological quality, using different specific culture media and biochemical tests. Water samples were analyzed within 24 hours of their purchase/collection. Samples were filtered with 0.45 micron and filters were plated in different media. Then media were incubated at 37˚C for 24-48 hours. Results: Morphological study and biochemical tests revealed a number of bacteria in different   brands of  bottled water. Heterotrophic bacteria(Gram positive cocci, Spore forming gram positive bacilli, non spore forming gram positive bacilli, gram negative bacilli, and gram negative coccobacilli; Pseudomonas and Stenotrophomonas counted in 70% of bottled water samples. There were no cases of fecal contamination or the presence of E.coli. Conclusions: Bottled water is not sterile and contains trace amounts of bacteria naturally present or introduced during processing. Testing drinking water for all possible pathogens is complex, time-consuming, and expensive. If only total coliform bacteria are detected in drinking water, the source is probably environmental. Since the significance of non-pathogenic heterotrophic bacteria in relation to health and diseases is not understood, there is an urgent need to establish a maximum limit for the heterotrophic count in the bottled mineral water. Growth conditions play a critical role in the recovery of heterotrophic bacteria in bottled drinking water.

Leptospira Contamination in Household and Environmental Water in Rural Communities in Southern Chile

Directory of Open Access Journals (Sweden)

Claudia Muñoz-Zanzi

2014-06-01

Full Text Available Leptospirosis is a zoonosis of global distribution that affects tropical and temperate areas. Under suitable conditions, Leptospira can survive in water and soil and contribute to human and animal infections. The objective of this study was to describe the presence of pathogenic Leptospira in peri-domestic water samples from rural households in southern Chile. Water samples, including puddles, containers, animal troughs, rivers, canals, and drinking water were collected from 236 households and tested for Leptospira using a PCR assay targeting the lipL32 gene. Evidence of Leptospira presence was detected in all sample types; overall, 13.5% (77/570 samples tested positive. A total of 10/22 (45.5% open containers, 12/83 (14.5% animal drinking sources, 9/47 (19.1% human drinking sources, and 36/306 (19.3% puddles tested positive. Lower income (OR = 4.35, p = 0.003, increased temperature (OR = 1.23, p < 0.001, and presence of dogs (OR = 15.9, p = 0.022 were positively associated with positive puddles. Increased number of rodent signs was associated with positive puddles in the household (OR = 3.22; however, only in the lower income households. There was no association between PCR positive rodents and puddles at the household level. Results revealed the ubiquity of Leptospira in the household environment and highlight the need to develop formal approaches for systematic monitoring.

Detection of Cryptosporidium and Cyclospora Oocysts from Environmental Water for Drinking and Recreational Activities in Sarawak, Malaysia.

Science.gov (United States)

Bilung, Lesley Maurice; Tahar, Ahmad Syatir; Yunos, Nur Emyliana; Apun, Kasing; Lim, Yvonne Ai-Lian; Nillian, Elexson; Hashim, Hashimatul Fatma

2017-01-01

Cryptosporidiosis and cyclosporiasis are caused by waterborne coccidian protozoan parasites of the genera Cryptosporidium and Cyclospora, respectively. This study was conducted to detect Cryptosporidium and Cyclospora oocysts from environmental water abstracted by drinking water treatment plants and recreational activities in Sarawak, Malaysia. Water samples (12 each) were collected from Sungai Sarawak Kanan in Bau and Sungai Sarawak Kiri in Batu Kitang, respectively. In addition, 6 water samples each were collected from Ranchan Recreational Park and UNIMAS Lake at Universiti Malaysia Sarawak, Kota Samarahan, respectively. Water physicochemical parameters were also recorded. All samples were concentrated by the iron sulfate flocculation method followed by the sucrose floatation technique. Cryptosporidium and Cyclospora were detected by modified Ziehl-Neelsen technique. Correlation of the parasites distribution with water physicochemical parameters was analysed using bivariate Pearson correlation. Based on the 24 total samples of environmental water abstracted by drinking water treatment plants, all the samples (24/24; 100%) were positive with Cryptosporidium , and only 2 samples (2/24; 8.33%) were positive with Cyclospora . Based on the 12 total samples of water for recreational activities, 4 samples (4/12; 33%) were positive with Cryptosporidium , while 2 samples (2/12; 17%) were positive with Cyclospora . Cryptosporidium oocysts were negatively correlated with dissolved oxygen (DO).

Drinking water quality assessment and corrosion mitigation in the hospital water supply system of Chacas Village (Peru

Directory of Open Access Journals (Sweden)

Riccardo Bigoni

2014-07-01

Full Text Available Rural hospitals in developing countries often lack appropriate water treatments to assure their water needs. In these facilities, due to water different uses and its use with medical equipment, water quality problems can cause very hazardous situations. In particular, corrosion of water distribution systems is a common issue that can cause unwanted changes in water quality and failures of the distribution system’s pipes. These considerations suggest that a complete monitoring program and water treatments to control and guarantee the water quality would be required in each health-care facility. This study assessed the quality of the water at the rural hospital of Chacas (Peru as measured via specific physical-chemical and microbiological parameters. The results show that the chemical and microbiological qualities of the water generally worsen from catchment to the hospital’s taps. Moreover, this work investigated the effects of a dolomite limestone filter installed to adjust the quality of the water distributed at the hospital and thereby mitigate the water’s corrosiveness. Corrosion indices were calculated to provide useful information on the water’s corrosiveness and positive results were obtained in reducing corrosiveness after the installation of the dolomite filter.

Microporous nano-MgO/diatomite ceramic membrane with high positive surface charge for tetracycline removal.

Science.gov (United States)

Meng, Xian; Liu, Zhimeng; Deng, Cheng; Zhu, Mengfu; Wang, Deyin; Li, Kui; Deng, Yu; Jiang, Mingming

2016-12-15

A novel microporous nano-MgO/diatomite ceramic membrane with high positive surface charge was prepared, including synthesis of precursor colloid, dip-coating and thermal decomposition. Combined SEM, EDS, XRD and XPS studies show the nano-MgO is irregularly distributed on the membrane surface or pore walls and forms a positively charged nano coating. And the nano-MgO coating is firmly attached to the diatomite membrane via SiO chemical bond. Thus the nano-MgO/diatomite membrane behaves strong electropositivity with the isoelectric point of 10.8. Preliminary filtration tests indicate that the as-prepared nano-MgO/diatomite membrane could remove approximately 99.7% of tetracycline in water through electrostatic adsorption effect. The desirable electrostatic property enables the nano-MgO/diatomite membrane to be a candidate for removal of organic pollutants from water. And it is convinced that there will be a great application prospect of charged ceramic membrane in water treatment field. Copyright © 2016 Elsevier B.V. All rights reserved.

Relationship of condylar position to disc position and morphology

Energy Technology Data Exchange (ETDEWEB)

Incesu, L.; Taskaya-Yilmaz, N. E-mail: nergizy@omu.edu.tr; Oeguetcen-Toller, M.; Uzun, E

2004-09-01

Introduction/objective: The purpose of this study was to assess whether condylar position, as depicted by magnetic resonance imaging, was an indicator of disc morphology and position. Methods and material: One hundred and twenty two TMJs of 61 patients with temporomandibular joint disorder were examined. Condylar position, disc deformity and degree of anterior disc displacement were evaluated by using magnetic resonance imaging. Results and discussion: Posterior condyle position was found to be the main feature of temporomandibular joints with slight and moderate anterior disc displacement. No statistical significance was found between the condylar position, and reducing and nonreducing disc positions. On the other hand, superior disc position was found to be statistically significant for centric condylar position. Conclusion: It was concluded that posterior condyle position could indicate anterior disc displacement whereas there was no relation between the position of condyle and the disc deformity.

The tracer function of isotope composition and deuterium excess parameter of water bodies on prospecting for geothermal water: taking the prospecting for geothermal water in Sanjianshui, Sichuan for example

International Nuclear Information System (INIS)

Yang Bo; Yin Guan

2003-01-01

Based on the isotope composition features of water bodies in Sanjiashui area, this paper use the theory of deuterium excess parameter (d) to discuss and cause of formulation, recharge source, removed patch, detained time and dynamics feature on ground water. These discussed problems have far-reaching meaning on evaluating the size of geothermal water, exploited potential of thermal spring and find new thermal spring in neighboring area. We analyze the relation of d and tritium content (T) on different water bodies in Sanjianshui area and draw some conclusions. Firstly, all water bodies in Sanjianshui origin from precipitation. Secondly, precipitation of northwest mountain area that have long removed patch and long detained time is the recharge resource of groundwater in basin. In addition, we demonstrate the possibility of existence of geothermal water in several positions of Sanjianshui area. (authors)

Highly Efficient Photocatalytic Water Splitting over Edge-Modified Phosphorene Nanoribbons.

Science.gov (United States)

Hu, Wei; Lin, Lin; Zhang, Ruiqi; Yang, Chao; Yang, Jinlong

2017-11-01

Two-dimensional phosphorene with desirable optoelectronic properties (ideal band gap, high carrier mobility, and strong visible light absorption) is a promising metal-free photocatalyst for water splitting. However, the band edge positions of the valence band maximum (VBM) and conduction band maximum (CBM) of phosphorene are higher than the redox potentials in photocatalytic water splitting reactions. Thus, phosphorene can only be used as the photocathode for hydrogen evolution reaction as a low-efficiency visible-light-driven photocatalyst for hydrogen production in solar water splitting cells. Here, we propose a new mechanism to improve the photocatalytic efficiency of phosphorene nanoribbons (PNRs) by modifying their edges for full reactions in photocatalytic water splitting. By employing first-principles density functional theory calculations, we find that pseudohalogen (CN and OCN) passivated PNRs not only show desired VBM and CBM band edge positions induced by edge electric dipole layer, but also possess intrinsic optoelectronic properties of phosphorene, for both water oxidation and hydrogen reduction in photocatalytic water splitting without using extra energy. Furthermore, our calculations also predict that the maximum energy conversion efficiency of heterojunction solar cells consisting of different edge-modified PNRs can be as high as 20% for photocatalytic water splitting.

Environmental and socioeconomic benefits and limitations of water harvesting techniques in semiarid regions

Science.gov (United States)

Díaz-Pereira, Elvira; Asunción Romero-Díaz, María; de Vente, Joris

2016-04-01

Under climate change, sustainable management of soil and water resources is increasingly important, especially in rainfed agroecosystems of semiarid environments. Water harvesting refers to a range of techniques for the collection and management of flood or rainwater for domestic and agricultural use and for water retention in natural ecosystems. Water harvesting represents a good example of sustainable management of water resources that contribute to water and food security. However, there are often environmental and socioeconomic constraints for implementation of water harvesting techniques, so each condition asks for a specific solution. Here we aim to highlight the environmental and socioeconomic benefits, requirements and limitations of different water harvesting techniques and to characterize their implications for provisioning, regulating, supporting, and cultural ecosystem services. We reviewed 62 water harvesting techniques for semiarid regions extracted from the WOCAT (World Overview of Conservation Approaches and Technologies) database. We discuss aspects related to: i) human and environmental characteristics, ii) cost-benefit ratio during implementation and maintenance phases, iii) socioeconomic and environmental impacts at local and regional scales, and, iv) impacts on ecosystem services. Our review reveals that water harvesting represents very diverse methods of collecting and managing floodwaters and surface runoff. We grouped techniques as 'floodwater harvesting', 'macro-catchment water harvesting', 'micro-catchment water harvesting', and 'rooftop and courtyard' water harvesting. Almost half of all technologies originates from traditional knowledge. The implementation of water harvesting is generally positive on the short-term, to very positive on the long-term, while its maintenance is very positive at short and long-term. However, perception depends on the type of water harvesting and local conditions. Most relevant socioeconomic benefits from

Aircraft and satellite monitoring of water quality in Lake Superior near Duluth

Science.gov (United States)

Scherz, J. P.; Sydor, M.; Vandomelen, J. F.

1974-01-01

Satellite images and low altitude aerial photographs often show vivid discolorations in water bodies. Extensive laboratory analysis shows that water reflectance, which causes brightness on aerial images, positively correlates to the water quality parameter of turbidity, which on a particular day correlates to suspended solids. Work with low altitude photography on three overcast days and with ERTS images on five clear days provides positive correlation of image brightness to the high turbidity and solids which are present in Lake Superior near Duluth over 50% of the time. Proper use of aerial images would have shown that an $8,000,000 drinking water intake constructed in the midst of this unpotable, turbid water should have been located 6 miles north in clear, usable water. Noise effects such as skylight reflection, atmospheric effects, and depth penetration also must be understood for operational use of remote sensing for water quality monitoring and are considered in the paper.

A modified closed flow through siphon system for the cultivation of marine or estuarine organisms under simulated conditions

Digital Repository Service at National Institute of Oceanography (India)

Nair, K.K.C.; Gopalakrishnan, T.C.; Sankaranarayanan, V.N.; Desai, B.N.

. Some of the principles used in the present modified design have come from the design of Nair et al., (1978) and Nair and Anger (1980) with lot of innovations to improve the working efficiency. The systems designed is protected under Government..., employing the same principles, in place of diarom/algal culture for water treatment, mangrove plants such as Rhizophora apiculata and Kandelia kandal were found very effective for removal of dissolved nutrients and other end products in the culture media...

Changing Planning by Changing Practice: How Water Managers Innovate Through Action

NARCIS (Netherlands)

Wessel, van M.; Buuren, van R.; Woerkum, van C.

2011-01-01

In this study, we show how water managers who were not in strategic decision-making positions strategized in order to innovate water management practice. They undertook actions in order to infuse water management with a pragmatic logic that in their view would be better able to handle complexity.

Environmental Impact Assessment of a Water Transfer Project

Directory of Open Access Journals (Sweden)

Pazoki

2015-07-01

Full Text Available Background Reliable water supplies for drinking and agriculture are some of the objectives for the sustainable development of every country. However, constructed facilities such as dams and irrigation networks and drainage can exert positive and negative effects directly or indirectly on the environment. The environmental impact assessment is a method for identifying the positive and negative effects caused by a plan and suggests performance management best practices aimed at lessening the negative impacts and augmenting the positive ones. Objectives The present study sought to evaluate the environmental impacts of the water transfer project of the Jooban Dam in two phases of preparation and operation. Materials and Methods A checklist containing the positive, negative, short-term, and long-term effects as well as the continuation and probable occurrence of these effects was used. Results The results showed that the negative environmental and social impacts of the project outweighed the positive impacts in terms of type, number, and intensity. Conclusions Unless there are well-thought out strategies for minimizing the undesirable impact on the environment, it is not advisable that such projects be permitted.

Analysis of antenna position measurements and weather station network data during the ALMA long baseline campaign of 2015

Science.gov (United States)

Hunter, Todd R.; Lucas, Robert; Broguière, Dominique; Fomalont, Ed B.; Dent, William R. F.; Phillips, Neil; Rabanus, David; Vlahakis, Catherine

2016-07-01

In a radio interferometer, the geometrical antenna positions are determined from measurements of the observed delay to each antenna from observations across the sky of many point sources whose positions are known to high accuracy. The determination of accurate antenna positions relies on accurate calibration of the dry and wet delay of the atmosphere above each antenna. For the Atacama Large Millimeter/Submillimeter Array (ALMA), with baseline lengths up to 15 kilometers, the geography of the site forces the height above mean sea level of the more distant antenna pads to be significantly lower than the central array. Thus, both the ground level meteorological values and the total water column can be quite different between antennas in the extended configurations. During 2015, a network of six additional weather stations was installed to monitor pressure, temperature, relative humidity and wind velocity, in order to test whether inclusion of these parameters could improve the repeatability of antenna position determinations in these configurations. We present an analysis of the data obtained during the ALMA Long Baseline Campaign of October through November 2015. The repeatability of antenna position measurements typically degrades as a function of antenna distance. Also, the scatter is more than three times worse in the vertical direction than in the local tangent plane, suggesting that a systematic effect is limiting the measurements. So far we have explored correcting the delay model for deviations from hydrostatic equilibrium in the measured air pressure and separating the partial pressure of water from the total pressure using water vapor radiometer (WVR) data. Correcting for these combined effects still does not provide a good match to the residual position errors in the vertical direction. One hypothesis is that the current model of water vapor may be too simple to fully remove the day-to-day variations in the wet delay. We describe possible new avenues of

CATV and the Broadcasters.

Science.gov (United States)

Flanagan, Bill

Competition between cable television systems (CATV) and regular broadcast stations concerns pay-TV and distant signal importation. The pay-TV that CATV provides competes with the networks by "siphoning" away sports and feature films, while the distant signals that CATV imports to a local market "fragment" the local audience and…

Instructional Integration of Disciplines for Promoting Children's Positive Attitudes towards Plants

Science.gov (United States)

Çìl, Emine

2016-01-01

Plants are an integral part of nature. Many plant species in almost any part of the world are under serious threats due to various reasons such as deforestation, pollution--of air, water and soil--caused by industrialisation, overgrazing and rapid population growth. It is likely that people have strong positive attitudes towards conservation of…

Tracking the position of the underwater robot for nuclear reactor inspection

International Nuclear Information System (INIS)

Jeo, J. W.; Kim, C. H.; Seo, Y. C.; Choi, Y. S.; Kim, S. H.

2003-01-01

The tracking procedure of the underwater mobile robot moving and submerging ahead to nuclear reactor vessel for visual inspection, which is required to find the foreign objects such as loose parts, is described. The yellowish underwater robot body tends to present a big contrast to boron solute cold water of nuclear reactor vessel, tinged with indigo by the Cerenkov effect. In this paper, we have found and tracked the positions of underwater mobile robot using the two color information, yellow and indigo. From the horizontal and vertical profiles analysis of the color image, the blue, green, and the gray component have the inferior signal-to-noise characteristics compared to the red component. The center coordinates extraction procedures areas follows. The first step is to segment the underwater robot body to cold water with indigo background. From the RGB color components of the entire monitoring image taken with the color CCD camera, we have selected the red color component. In the selected red image, we extracted the positions of the underwater mobile robot using the following process sequences; binarization, labelling, and centroid extraction techniques. In the experiment carried out at the Youngkwang unit 5 nuclear reactor vessel, we have tracked the center positions of the underwater robot submerged near the cold leg and the hot leg way, which is fathomed to 10m deep in depth. When the position of the robot vehicle fluctuates between the previous and the current image frame due to the flickering noise and light source, installed temporally in the bottom of the reactor vessel, we adaptively adjusted the ROI window. Adding the ROI windows of the previous frame to the current frame, and then setting up the ROI window of the next image frame, we can robustly track the positions of the underwater robot and control the target position's divergence. From these facts, we can conclude that using the red component from color camera is more efficient tracking method

Positive mood broadens visual attention to positive stimuli.

Science.gov (United States)

Wadlinger, Heather A; Isaacowitz, Derek M

2006-03-01

In an attempt to investigate the impact of positive emotions on visual attention within the context of Fredrickson's (1998) broaden-and-build model, eye tracking was used in two studies to measure visual attentional preferences of college students (n=58, n=26) to emotional pictures. Half of each sample experienced induced positive mood immediately before viewing slides of three similarly-valenced images, in varying central-peripheral arrays. Attentional breadth was determined by measuring the percentage viewing time to peripheral images as well as by the number of visual saccades participants made per slide. Consistent with Fredrickson's theory, the first study showed that individuals induced into positive mood fixated more on peripheral stimuli than did control participants; however, this only held true for highly-valenced positive stimuli. Participants under induced positive mood also made more frequent saccades for slides of neutral and positive valence. A second study showed that these effects were not simply due to differences in emotional arousal between stimuli. Selective attentional broadening to positive stimuli may act both to facilitate later building of resources as well as to maintain current positive affective states.

Occurrence, molecular characterization and antibiogram of water quality indicator bacteria in river water serving a water treatment plant

Energy Technology Data Exchange (ETDEWEB)

Okeke, Benedict C., E-mail: bokeke@aum.edu [Department of Biology, Auburn University at Montgomery, P.O. Box 244023, Montgomery, AL 36124 (United States); Thomson, M. Sue [Department of Biology, Auburn University at Montgomery, P.O. Box 244023, Montgomery, AL 36124 (United States); Moss, Elica M. [Department of Natural Resources and Environmental Science, Alabama A and M University, AL 35762 (United States)

2011-11-01

Water pollution by microorganisms of fecal origin is a current world-wide public health concern. Total coliforms, fecal coliforms (Escherichia coli) and enterococci are indicators commonly used to assess the microbiological safety of water resources. In this study, influent water samples and treated water were collected seasonally from a water treatment plant and two major water wells in a Black Belt county of Alabama and evaluated for water quality indicator bacteria. Influent river water samples serving the treatment plant were positive for total coliforms, fecal coliforms (E. coli), and enterococci. The highest number of total coliform most probable number (MPN) was observed in the winter (847.5 MPN/100 mL) and the lowest number in the summer (385.6 MPN/100 mL). Similarly E. coli MPN was substantially higher in the winter (62.25 MPN/100 mL). Seasonal variation of E. coli MPN in influent river water samples was strongly correlated with color (R{sup 2} = 0.998) and turbidity (R{sup 2} = 0.992). Neither E. coli nor other coliform type bacteria were detected in effluent potable water from the treatment plant. The MPN of enterococci was the highest in the fall and the lowest in the winter. Approximately 99.7 and 51.5 enterococci MPN/100 mL were recorded in fall and winter seasons respectively. One-way ANOVA tests revealed significant differences in seasonal variation of total coliforms (P < 0.05), fecal coliforms (P < 0.01) and enterococci (P < 0.01). Treated effluent river water samples and well water samples revealed no enterococci contamination. Representative coliform bacteria selected by differential screening on Coliscan Easygel were identified by 16S ribosomal RNA gene sequence analysis. E. coli isolates were sensitive to gentamicin, trimethoprim/sulfamethazole, ciprofloxacin, vancomycin, tetracycline, ampicillin, cefixime, and nitrofurantoin. Nonetheless, isolate BO-54 displayed decreased sensitivity compared to other E. coli isolates. Antibiotic sensitivity

Occurrence, molecular characterization and antibiogram of water quality indicator bacteria in river water serving a water treatment plant

International Nuclear Information System (INIS)

Okeke, Benedict C.; Thomson, M. Sue; Moss, Elica M.

2011-01-01

Water pollution by microorganisms of fecal origin is a current world-wide public health concern. Total coliforms, fecal coliforms (Escherichia coli) and enterococci are indicators commonly used to assess the microbiological safety of water resources. In this study, influent water samples and treated water were collected seasonally from a water treatment plant and two major water wells in a Black Belt county of Alabama and evaluated for water quality indicator bacteria. Influent river water samples serving the treatment plant were positive for total coliforms, fecal coliforms (E. coli), and enterococci. The highest number of total coliform most probable number (MPN) was observed in the winter (847.5 MPN/100 mL) and the lowest number in the summer (385.6 MPN/100 mL). Similarly E. coli MPN was substantially higher in the winter (62.25 MPN/100 mL). Seasonal variation of E. coli MPN in influent river water samples was strongly correlated with color (R 2 = 0.998) and turbidity (R 2 = 0.992). Neither E. coli nor other coliform type bacteria were detected in effluent potable water from the treatment plant. The MPN of enterococci was the highest in the fall and the lowest in the winter. Approximately 99.7 and 51.5 enterococci MPN/100 mL were recorded in fall and winter seasons respectively. One-way ANOVA tests revealed significant differences in seasonal variation of total coliforms (P < 0.05), fecal coliforms (P < 0.01) and enterococci (P < 0.01). Treated effluent river water samples and well water samples revealed no enterococci contamination. Representative coliform bacteria selected by differential screening on Coliscan Easygel were identified by 16S ribosomal RNA gene sequence analysis. E. coli isolates were sensitive to gentamicin, trimethoprim/sulfamethazole, ciprofloxacin, vancomycin, tetracycline, ampicillin, cefixime, and nitrofurantoin. Nonetheless, isolate BO-54 displayed decreased sensitivity compared to other E. coli isolates. Antibiotic sensitivity pattern

Water exchange traded funds: A study on idiosyncratic risk using Markov switching analysis

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Gurudeo Anand Tularam

2016-12-01

Full Text Available We investigate the relationship between idiosyncratic risk and return among four water exchange traded funds—PowerShares Water Resources Portfolio, Power Shares Global Water, First Trust ISE Water Index Fund, and Guggenheim S&P Global Water Index ETF using the Markov switching model for the period 2007–2015. The generated transition probabilities in this paper show that there is a high and low probability of switching between Regimes 1 and 3, respectively. Moreover, we find that the idiosyncratic risk for most of the exchange traded funds move from low volatility (Regime 2 to very low volatility (Regime 1 and 3. Our study also identify that the beta coefficients are positive and entire values are less than 1. Thus, it seems that water investment has a lower systematic risk and a positive effect on the water exchange traded index funds returns during different regimes.

Evaporation Rate of Water as a Function of a Magnetic Field and Field Gradient

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Peng Shang

2012-12-01

Full Text Available The effect of magnetic fields on water is still a highly controversial topic despite the vast amount of research devoted to this topic in past decades. Enhanced water evaporation in a magnetic field, however, is less disputed. The underlying mechanism for this phenomenon has been investigated in previous studies. In this paper, we present an investigation of the evaporation of water in a large gradient magnetic field. The evaporation of pure water at simulated gravity positions (0 gravity level (ab. g, 1 g, 1.56 g and 1.96 g in a superconducting magnet was compared with that in the absence of the magnetic field. The results showed that the evaporation of water was indeed faster in the magnetic field than in the absence of the magnetic field. Furthermore, the amount of water evaporation differed depending on the position of the sample within the magnetic field. In particular, the evaporation at 0 g was clearly faster than that at other positions. The results are discussed from the point of view of the evaporation surface area of the water/air interface and the convection induced by the magnetization force due to the difference in the magnetic susceptibility of water vapor and the surrounding air.

Evaporation rate of water as a function of a magnetic field and field gradient.

Science.gov (United States)

Guo, Yun-Zhu; Yin, Da-Chuan; Cao, Hui-Ling; Shi, Jian-Yu; Zhang, Chen-Yan; Liu, Yong-Ming; Huang, Huan-Huan; Liu, Yue; Wang, Yan; Guo, Wei-Hong; Qian, Ai-Rong; Shang, Peng

2012-12-11

The effect of magnetic fields on water is still a highly controversial topic despite the vast amount of research devoted to this topic in past decades. Enhanced water evaporation in a magnetic field, however, is less disputed. The underlying mechanism for this phenomenon has been investigated in previous studies. In this paper, we present an investigation of the evaporation of water in a large gradient magnetic field. The evaporation of pure water at simulated gravity positions (0 gravity level (ab. g), 1 g, 1.56 g and 1.96 g) in a superconducting magnet was compared with that in the absence of the magnetic field. The results showed that the evaporation of water was indeed faster in the magnetic field than in the absence of the magnetic field. Furthermore, the amount of water evaporation differed depending on the position of the sample within the magnetic field. In particular, the evaporation at 0 g was clearly faster than that at other positions. The results are discussed from the point of view of the evaporation surface area of the water/air interface and the convection induced by the magnetization force due to the difference in the magnetic susceptibility of water vapor and the surrounding air.

Evaporation Rate of Water as a Function of a Magnetic Field and Field Gradient

Science.gov (United States)

Guo, Yun-Zhu; Yin, Da-Chuan; Cao, Hui-Ling; Shi, Jian-Yu; Zhang, Chen-Yan; Liu, Yong-Ming; Huang, Huan-Huan; Liu, Yue; Wang, Yan; Guo, Wei-Hong; Qian, Ai-Rong; Shang, Peng

2012-01-01

The effect of magnetic fields on water is still a highly controversial topic despite the vast amount of research devoted to this topic in past decades. Enhanced water evaporation in a magnetic field, however, is less disputed. The underlying mechanism for this phenomenon has been investigated in previous studies. In this paper, we present an investigation of the evaporation of water in a large gradient magnetic field. The evaporation of pure water at simulated gravity positions (0 gravity level (ab. g), 1 g, 1.56 g and 1.96 g) in a superconducting magnet was compared with that in the absence of the magnetic field. The results showed that the evaporation of water was indeed faster in the magnetic field than in the absence of the magnetic field. Furthermore, the amount of water evaporation differed depending on the position of the sample within the magnetic field. In particular, the evaporation at 0 g was clearly faster than that at other positions. The results are discussed from the point of view of the evaporation surface area of the water/air interface and the convection induced by the magnetization force due to the difference in the magnetic susceptibility of water vapor and the surrounding air. PMID:23443127

Research Staff | Water Power | NREL

Science.gov (United States)

Research Staff Research Staff Learn more about the expertise and technical skills of the water power research team and staff at NREL. Name Position Email Phone Anstedt, Sheri Professional III-Writer /Editor/Web Content Sheri.Anstedt@nrel.gov 303-275-3255 Baker, Donald Research Technician V-Electrical

Direction of rational use of water at livestock facilities

Science.gov (United States)

Potseluev, A. A.; Nazarov, I. V.

2017-05-01

The article notes the world water shortage problem. Against this background, Russia’s agricultural production is considered, in particular the livestock sector as the main consumer of water resources. The structure of the main technological processes at livestock facilities is given and possible technological damage is indicated in case of the lack of technological processes for servicing animals and poultry with water. The direction of rational use of water based on the introduction of new technical and technological solutions of water supply systems and means is substantiated. Constructive solutions of systems and facilities that help to reduce water consumption are presented, and as well a possible positive effect.

Experimental study on the simple water hammer pump; Kan`igata water hammer pump ni kansuru kenkyu

Energy Technology Data Exchange (ETDEWEB)

Muto, M; Ushiyama, I [Ashikaga Institute of Technology, Tochigi (Japan)

1997-11-25

Outlined herein are experimental results with a water hammer pump. It is a unique pump in that it depends only on potential energy of water to pump-up water. Water flows downwards from a reservoir at a high position into the pump , and is released from the exhaust valve. When velocity of water flowing in the pipe reaches a certain level, hydraulic force exceeds gravity of the exhaust valve to rapidly closes it, which is accompanied by rapid increase in pressure in the pump. High-pressure water flows into the air chamber, after pushing up the lifting valve, to compress air in the chamber. The lifting valve is closed, when pressure in the air chamber exceeds that in the pump, to pump up water in the chamber through the lifting pipe. Closure of the lifting valve produces a negative pressure within the pump, which, together with gravity of the exhaust valve, opens the valve again. The pump lifts water at 1.64l/min under the conditions of head: 3m and lift: 6m at an efficiency of 48.1%. 1 ref., 4 fig., 2 tab.

Factors Stimulating Propagation of Legionellae in Cooling Tower Water

OpenAIRE

Yamamoto, Hiroyuki; Sugiura, Minoru; Kusunoki, Shinji; Ezaki, Takayuki; Ikedo, Masanari; Yabuuchi, Eiko

1992-01-01

Our survey of cooling tower water demonstrated that the highest density of legionellae, ≥104 CFU/100 ml, appeared in water containing protozoa, ≥102 MPN/100 ml, and heterotrophic bacteria, ≥106 CFU/100 ml, at water temperatures between 25 and 35°C. Viable counts of legionellae were detected even in the winter samples, and propagation, up to 105 CFU/100 ml, occurs in summer. The counts of legionellae correlated positively with increases in water temperature, pH, and protozoan counts, but not w...

Molecular cobalt pentapyridine catalysts for generating hydrogen from water

Science.gov (United States)

Long, Jeffrey R; Chang, Christopher J; Sun, Yujie

2013-11-05

A composition of matter suitable for the generation of hydrogen from water is described, the positively charged cation of the composition including the moiety of the general formula. [(PY5Me.sub.2)CoL].sup.2+, where L can be H.sub.2O, OH.sup.-, a halide, alcohol, ether, amine, and the like. In embodiments of the invention, water, such as tap water or sea water can be subject to low electric potentials, with the result being, among other things, the generation of hydrogen.

REMOVING BIOMASS FROM WATER PONDS AND SMALL WATER RESERVOIRS BY USING NON-WOVEN FILTERS

Directory of Open Access Journals (Sweden)

Jakub Nieć

2015-10-01

Full Text Available Small water bodies, for example garden ponds, play many functions in the environment, including biocenotic, hydrological, climatic, sozological, landfill-creative, and aesthetic. Due to their small size, these reservoirs are sensitive to external and internal factors, they are also a common natural contaminants receivers. Nonwoven filters have been investigated for several years as a useful device for treatment of domestic wastewater pre-treated in a septic tank. The aim of this study was to verify the possibility of using this type of filters for water originating from small water body purification. The effectiveness of filters were tested on the water originating from the garden pond, contained high levels of nutrients and intensive algal bloom. Research was carried out on three filters (each filter consisted of four geotextile TS 20 layers. Basic water quality indicators: total suspended solids, turbidity, COD and BOD5, temperature, pH and dissolved oxygen were measured. The research results can be considered as satisfactory in terms of mechanical treatment (removal of turbidity and total suspended solids. An important positive effect of the filters was the oxygenation of the treated water, which is especially important for fish.

Water-energy nexus for urban water systems: A comparative review on energy intensity and environmental impacts in relation to global water risks

International Nuclear Information System (INIS)

Lee, Mengshan; Keller, Arturo A.; Chiang, Pen-Chi; Den, Walter; Wang, Hongtao; Hou, Chia-Hung; Wu, Jiang; Wang, Xin; Yan, Jinyue

2017-01-01

Highlights: •This study quantifies the nexus as energy intensity and greenhouse gas potential. •Baseline water stress and return flow ratio are identified as water risks. •Source water accessibility significantly contributes to variations in the nexus. •Water risks have little impact on the nexus of wastewater systems. •Study on the nexus is suggested to be conducted at regional levels. -- Abstract: The importance of the interdependence between water and energy, also known as the water-energy nexus, is well recognized. The water-energy nexus is typically characterized in resource use efficiency terms such as energy intensity. This study aims to explore the quantitative results of the nexus in terms of energy intensity and environmental impacts (mainly greenhouse gas emissions) on existing water systems within urban water cycles. We also characterized the influence of water risks on the water-energy nexus, including baseline water stress (a water quantity indicator) and return flow ratio (a water quality indicator). For the 20 regions and 4 countries surveyed (including regions with low to extremely high water risks that are geographically located in Africa, Australia, Asia, Europe, and North America), their energy intensities were positively related to the water risks. Regions with higher water risks were observed to have relatively higher energy and GHG intensities associated with their water supply systems. This mainly reflected the major influence of source water accessibility on the nexus, particularly for regions requiring energy-intensive imported or groundwater supplies, or desalination. Regions that use tertiary treatment (for water reclamation or environmental protection) for their wastewater treatment systems also had relatively higher energy and GHG emission intensities, but the intensities seemed to be independent from the water risks. On-site energy recovery (e.g., biogas or waste heat) in the wastewater treatment systems offered a great

Water Isotope framework for lake water balance monitoring and modelling in the Nam Co Basin, Tibetan Plateau

Directory of Open Access Journals (Sweden)

Shichang Kang

2017-08-01

New hydrological insights: A water isotope framework for the Nam Co basin, including the Local Meteoric Water Line, limiting isotopic composition of evaporation and two hypothetical evaporation trajectories, is established. We further applied the isotope mass balance model to estimate the overall isotopic composition of input water to the Nam Co, the evaporation over inputs ratios (E/I for three consecutive years, and the water yields (Wy, depth equivalent runoff at a basin scale. Our results clearly suggest a positive water budget (i.e., E/I < 1, providing another line of evidence that the subsurface leakage from Nam Co is likely. The discrepancy between isotope-based water yields estimations and field-based runoff observations suggest that, compared to the well-studied Nyainqentanglha Mountains and southwestern mountains, the ridge-and-valley landscape in the western highlands and northwestern hogbacks are possibly low yields area, which should draw more research attentions in future hydrological investigations.

Positioning consumption

DEFF Research Database (Denmark)

Halkier, Bente; Keller, Margit

2014-01-01

positionings emerges based on empirical examples of research in parent–children consumption. Positionings are flexible discursive fixations of the relationship between the performances of the practitioner, other practitioners, media discourse and consumption activities. The basic positioning types...... are the practice maintenance and the practice change position, with different sorts of adapting in between. Media discourse can become a resource for a resistant position against social control or for an appropriating position in favour of space for action. Regardless of the current relation to a particular media......This article analyses the ways in which media discourses become a part of contested consumption activities. We apply a positioning perspective with practice theory to focus on how practitioners relate to media discourse as a symbolic resource in their everyday practices. A typology of performance...

Tide dependent seasonal changes in water quality and assimilative capacity of anthropogenically influenced Mormugao harbour water

Digital Repository Service at National Institute of Oceanography (India)

Shirodkar, P.V.; Deepthi, M.; Vethamony, P.; Mesquita, A.M.; Pradhan, U.K.; Babu, M.T.; Verlecar, X.N.; Haldankar, S.R.

Water quality data from Mormugao harbour area at the mouth of Zuari estuary in Goa have been obtained over two tidal cycles monthly for the year 2003 to 2004. R-mode factor analyses of the data indicated strong positive loadings of coliforms...

Effects of supine, prone, and lateral positions on cardiovascular and renal variables in humans

DEFF Research Database (Denmark)

Pump, Bettina; Talleruphuus, Ulrik; Christensen, Niels Juel

2002-01-01

The hypothesis was tested that changing the direction of the transverse gravitational stress in horizontal humans modulates cardiovascular and renal variables. On different study days, 14 healthy males were placed for 6 h in either the horizontal supine or prone position following 3 h of being...... supine. Eight of the subjects were in addition investigated in the horizontal left lateral position. Compared with supine, the prone position slightly increased free water clearance (349 +/- 38 vs. 447 +/- 39 ml/6 h, P = 0.05) and urine output (1,387 +/- 55 vs. 1,533 +/- 52 ml/6 h, P = 0...

Occurrence of Cryptosporidium spp. and Giardia spp. in a public water-treatment system, Paraná, Southern Brazil

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Jonatas Campos Almeida

Full Text Available The purpose of this study was to investigate the occurrence of Cryptosporidium spp. and Giardia spp. in a public water-treatment system. Samples of raw and treated water were collected and concentrated using the membrane filtration technique. Direct Immunofluorescence Test was performed on the samples. DNA extraction using a commercial kit was performed and the DNA extracted was submitted to a nested-PCR reaction (n-PCR and sequencing. In the immunofluorescence, 2/24 (8.33% samples of raw water were positive for Giardia spp.. In n-PCR and sequencing, 2/24 (8.33% samples of raw water were positive for Giardia spp., and 2/24 (8.33% samples were positive for Cryptosporidium spp.. The sequencing showed Cryptosporidium parvum and Giardia duodenalis DNA. In raw water, there was moderate correlation among turbidity, color and Cryptosporidium spp. and between turbidity and Giardia spp.. The presence of these protozoans in the water indicates the need for monitoring for water-treatment companies.

Irradiation capability of Japanese materials test reactor for water chemistry experiments

International Nuclear Information System (INIS)

Hanawa, Satoshi; Hata, Kuniki; Chimi, Yasuhiro; Nishiyama, Yutaka; Nakamura, Takehiko

2012-09-01

Appropriate understanding of water chemistry in the core of LWRs is essential as chemical species generated due to water radiolysis by neutron and gamma-ray irradiation govern corrosive environment of structural materials in the core and its periphery, causing material degradation such as stress corrosion cracking. Theoretical model calculation such as water radiolysis calculation gives comprehensive understanding of water chemistry at irradiation field where we cannot directly monitor. For enhancement of the technology, accuracy verification of theoretical models under wide range of irradiation conditions, i.e. dose rate, temperature etc., with well quantified in-pile measurement data is essential. Japan Atomic Energy Agency (JAEA) has decided to launch water chemistry experiments for obtaining data that applicable to model verification as well as model benchmarking, by using an in-pile loop which will be installed in the Japan Materials Testing Reactor (JMTR). In order to clarify the irradiation capability of the JMTR for water chemistry experiments, preliminary investigations by water radiolysis / ECP model calculations were performed. One of the important irradiation conditions for the experiments, i.e. dose rate by neutron and gamma-ray, can be controlled by selecting irradiation position in the core. In this preliminary study, several representative irradiation positions that cover from highest to low absorption dose rate were chosen and absorption dose rate at the irradiation positions were evaluated by MCNP calculations. As a result of the calculations, it became clear that the JMTR could provide the irradiation conditions close to the BWR. The calculated absorption dose rate at each irradiation position was provided to water radiolysis calculations. The radiolysis calculations were performed under various conditions by changing absorption dose rate, water chemistry of feeding water etc. parametrically. Qualitatively, the concentration of H 2 O 2 , O 2 and

Impact of heated waters on water quality and macroinvertebrate community in the Narew River (Poland

Directory of Open Access Journals (Sweden)

Krolak Elzbieta

2017-07-01

Full Text Available The effect of heated waters from coal-burning power stations on the water parameters and the occurrence of macroinvertebrates depends on the individual characteristics of the river to which the heated waters are discharged. The objective of the study was to assess the impact of heated water from the Ostrołęka Power Station on selected water properties and the macroinvertebrate community in the Narew River. Samples were collected in years: 2013-2016 along two river stretches: upstream and downstream of the canal. The water temperature was higher and the oxygen concentrations were lower at the downstream sites compared to the upstream sites of the canal. The values of conductivity, concentrations of nitrates, phosphates, chlorides and calcium were similar at the sampling sites. A total of 33 families of macrozoobenthos were found. The numbers of families were positively correlated with the temperature and conductivity and negatively correlated with oxygen. The heated waters were found to have no effect on the Shannon-Wiener diversity index. The inflow of heated waters increased the percentage of Gammaridae, represented by species Dikerogammarus haemobaphes (Eichwald, 1841 and decreased the percentage of Chironomidae. The presence of the thermophilous bivalve Sinanodonta woodiana (Lea, 1934 was noted downstream of the canal.

Antibiotic-resistant bacteria in drinking water.

Science.gov (United States)

Armstrong, J L; Shigeno, D S; Calomiris, J J; Seidler, R J

1981-08-01

We analyzed drinking water from seven communities for multiply antibiotic-resistant (MAR) bacteria (bacteria resistant to two or more antibiotics) and screened the MAR bacterial isolates obtained against five antibiotics by replica plating. Overall, 33.9% of 2,653 standard plate count bacteria from treated drinking waters were MAR. Two different raw water supplies for two communities carried MAR standard plate count bacteria at frequencies of 20.4 and 18.6%, whereas 36.7 and 67.8% of the standard plate count populations from sites within the respective distribution systems were MAR. Isolate identification revealed that MAR gram-positive cocci (Staphylococcus) and MAR gram-negative, nonfermentative rods (Pseudomonas, Alcaligenes, Moraxella-like group M, and Acinetobacter) were more common in drinking waters than in untreated source waters. Site-to-site variations in generic types and differences in the incidences of MAR organisms indicated that shedding of MAR bacteria living in pipelines may have contributed to the MAR populations in tap water. We conclude that the treatment of raw water and its subsequent distribution select for standard plate count bacteria exhibiting the MAR phenotype.

Fast reactors. Thermal calculations of annulus application to Phenix

International Nuclear Information System (INIS)

Kung, J.P.; Gama, J.M.

1975-01-01

The gas convection phenomena involved in the annuli of the penetrations of the heat exchanger of the Phenix reactor are analyzed and the calculations performed using the BINIX program developed by GAAA to study the same phenomena are presented. The theory/experience comparison led to a better understanding of thermo-siphon phenomena [fr

Acute and chronic effects of acidic pH on four subtropical frog species

African Journals Online (AJOL)

2016-01-01

Jan 1, 2016 ... responsible for about 90% of the nitrogen oxide (NOx) that is emitted in South ... premier conservation areas, KNP has a mandate to conserve and manage all ... ians, most focused on effects of metals (23%), acid precipitation. (22%) and .... leaves. Excess food was siphoned out of the containers to reduce.

Near-bed gradients in particles and nutrients above a mussel bed in the Limfjorden: influence of physical mixing and mussel filtration

NARCIS (Netherlands)

Petersen, J.K.; Maar, M.; Ysebaert, T.; Herman, P.M.J.

2013-01-01

The aim of this field study was to investigate the role of mussels on near-bed layer characteristics at different hydrodynamic regimes in a micro-tidal system. At Løgstør Broad, the Limfjorden, Denmark, we deployed ‘siphon mimics’ to sample chlorophyll a (chl a), particulate organic carbon (POC) and

Significance of Waterway Navigation Positioning Systems On Ship's Manoeuvring Safety

Science.gov (United States)

Galor, W.

The main goal of navigation is to lead the ship to the point of destination safety and efficiently. Various factors may affect ship realisating this process. The ship movement on waterway are mainly limited by water area dimensions (surface and depth). These limitations cause the requirement to realise the proper of ship movement trajectory. In case when this re requirement cant't fulfil then marine accident may happend. This fact is unwanted event caused losses of human health and life, damage or loss of cargo and ship, pollution of natural environment, damage of port structures or blocking the port of its ports and lost of salvage operation. These losses in same cases can be catas- trophical especially while e.i. crude oil spilling could be place. To realise of safety navigation process is needed to embrace the ship's movement trajectory by waterways area. The ship's trajectory is described by manoeuvring lane as a surface of water area which is require to realise of safety ship movement. Many conditions affect to ship manoeuvring line. The main are following: positioning accuracy, ship's manoeuvring features and phenomena's of shore and ship's bulk common affecting. The accuracy of positioning system is most important. This system depends on coast navigation mark- ing which can range many kinds of technical realisation. Mainly used systems based on lights (line), radionavigation (local system or GPS, DGPS), or radars. If accuracy of positiong is higer, then safety of navigation is growing. This article presents these problems exemplifying with approaching channel to ports situated on West Pomera- nian water region.

Effects of positive end-expiratory pressure on renal function.

Science.gov (United States)

Järnberg, P O; de Villota, E D; Eklund, J; Granberg, P O

1978-01-01

The effects were studied positive end-expiratory pressure (PEEP) on renal function in eight patients with acute respiratory failure, requiring mechanical ventilation. On application of PEEP + 10 cm H2O, central venous pressure increased, systolic blood pressure decreased, urine flow and PAH-clearance were reduced, while inulin clearance remained stable. There was a marked increase in fractional sodium reabsorption and a concurrent decrease in fractional osmolal excretion. Fractional free-water clearance and the ratio UOsm/POsm did change.

Bacteria-free water for automatic washer-disinfectors: an impossible dream?

Science.gov (United States)

Cooke, R P; Whymant-Morris, A; Umasankar, R S; Goddard, S V

1998-05-01

The ability of a new automatic washer-disinfector system (AWDS), fitted with a water filtration system to provide bacteria-free water and so avoid the risk of mycobacterial contamination of fibreoptic bronchoscopes, was examined. Four new Astec 'MP' Safescope washer-disinfectors, with coarse and fine (0.2 micron) filters attached close to the outlet taps, were supplied with non-softened mains water. Water samples from the tank supply and outlet taps were regularly assessed for bacterial quality over a six-month period. Outlet samples were also analysed after fine filter change and purgation with peracetic acid. All bronchoalveolar lavage specimens (BALS) were stained and cultured for mycobacteria. Only 13 out of 53 outlet samples (24%) were culture-negative. There was no improvement after filter change. Residual anti-bacterial effect of peracetic acid lasted up to 48 h following AWDS purgation. No tank samples were bacteria-free. Sixty BALS were processed, two samples were culture-positive and grew M. tuberculosis and one was also smear-positive. Though mycobacterial contamination of bronchoscopes was not evident, the water filtration system was unable to reliably provide sterile rinse water.

False Position, Double False Position and Cramer's Rule

Science.gov (United States)

Boman, Eugene

2009-01-01

We state and prove the methods of False Position (Regula Falsa) and Double False Position (Regula Duorum Falsorum). The history of both is traced from ancient Egypt and China through the work of Fibonacci, ending with a connection between Double False Position and Cramer's Rule.

Structure of the floating water bridge and water in an electric field.

Science.gov (United States)

Skinner, Lawrie B; Benmore, Chris J; Shyam, Badri; Weber, J K R; Parise, John B

2012-10-09

The floating water bridge phenomenon is a freestanding rope-shaped connection of pure liquid water, formed under the influence of a high potential difference (approximately 15 kV). Several recent spectroscopic, optical, and neutron scattering studies have suggested that the origin of the bridge is associated with the formation of anisotropic chains of water molecules in the liquid. In this work, high energy X-ray diffraction experiments have been performed on a series of floating water bridges as a function of applied voltage, bridge length, and position within the bridge. The two-dimensional X-ray scattering data showed no direction-dependence, indicating that the bulk water molecules do not exhibit any significant preferred orientation along the electric field. The only structural changes observed were those due to heating, and these effects were found to be the same as for bulk water. These X-ray scattering measurements are supported by molecular dynamics (MD) simulations which were performed under electric fields of 10(6) V/m and 10(9) V/m. Directional structure factor calculations were made from these simulations parallel and perpendicular to the E-field. The 10(6) V/m model showed no significant directional-dependence (anisotropy) in the structure factors. The 10(9) V/m model however, contained molecules aligned by the E-field, and had significant structural anisotropy.

Positive-Buoyancy Rover for Under Ice Mobility

Science.gov (United States)

Leichty, John M.; Klesh, Andrew T.; Berisford, Daniel F.; Matthews, Jaret B.; Hand, Kevin P.

2013-01-01

A buoyant rover has been developed to traverse the underside of ice-covered lakes and seas. The rover operates at the ice/water interface and permits direct observation and measurement of processes affecting freeze- over and thaw events in lake and marine environments. Operating along the 2- D ice-water interface simplifies many aspects of underwater exploration, especially when compared to submersibles, which have difficulty in station-keeping and precision mobility. The buoyant rover consists of an all aluminum body with two aluminum sawtooth wheels. The two independent body segments are sandwiched between four actuators that permit isolation of wheel movement from movement of the central tether spool. For normal operations, the wheels move while the tether spool feeds out line and the cameras on each segment maintain a user-controlled fixed position. Typically one camera targets the ice/water interface and one camera looks down to the lake floor to identify seep sources. Each wheel can be operated independently for precision turning and adjustments. The rover is controlled by a touch- tablet interface and wireless goggles enable real-time viewing of video streamed from the rover cameras. The buoyant rover was successfully deployed and tested during an October 2012 field campaign to investigate methane trapped in ice in lakes along the North Slope of Alaska.

Positive selection in the leucine-rich repeat domain of Gro1 genes in ...

Indian Academy of Sciences (India)

history during which the main structure of the domain has been conserved such that ... from the column using 100 μL of distilled water. The LRR fragments from the ... ture of the domain and to obtain the best PDB template for mapping positive ...

The Role of Positive Emotions in Positive Psychology: The Broaden-and-Build Theory of Positive Emotions.

Science.gov (United States)

Fredrickson, Barbara L.

2001-01-01

Describes the broaden-and-build theory of positive emotions, situating it within the field of positive psychology. The theory posits that experiences of positive emotions broaden people's momentary thought-action repertoires, which in turn build their enduring personal resources (physical, intellectual, social, and psychological). Reviews…

Ubiquitous positioning

CERN Document Server

Mannings, Robin

2008-01-01

This groundbreaking resource offers a practical, in-depth understanding of Ubiquitous Positioning - positioning systems that identify the location and position of people, vehicles and objects in time and space in the digitized networked economy. The future and growth of ubiquitous positioning will be fueled by the convergence of many other areas of technology, from mobile telematics, Internet technology, and location systems, to sensing systems, geographic information systems, and the semantic web. This first-of-its-kind volume explores ubiquitous positioning from a convergence perspective, of

A Sleep Position Trainer for positional sleep apnea

DEFF Research Database (Denmark)

Laub, Rasmus R; Tønnesen, Philip; Jennum, Poul J

2017-01-01

We tested the effect of the Sleep Position Trainer, a vibrational device, for positional sleep apnea in an open, randomized controlled trial with 101 patients, where 52 patients were allocated to Sleep Position Trainer and 49 patients to a non-treatment control group for 2 months (Part 1). All...... patients were then followed as a cohort for a period of 6 months with use of the Sleep Position Trainer (Part 2). The participants were assessed with polygraphy at entry, and after 2 and 6 months. The mean apnea-hypopnea index supine was 35 per h (SD, 18) in the Sleep Position Trainer group and 38 per h...... (SD, 15) in the control group at entry. In a per protocol analysis, the mean total apnea-hypopnea index at entry and after 2 months in the Sleep Position Trainer group was 18 per h (SD, 10) and 10 per h (SD, 9; P

ENDOR determination of the proton positions around Gd3+ in La(C2H5SO4)3.9H2O

International Nuclear Information System (INIS)

Beer, R. de; Biesboer, F.; Ormondt, D. van

1976-01-01

The water proton positions around Gd 3+ in La(C 2 H 5 SO 4 ) 3 .9H 2 O have been determined by means of ENDOR. The positions of the nearest neighbour water oxygens are discussed on the basis of a superposition model analysis of the ratios b 2 0 /A 2 0 2 >, b 6 6 /b 6 0 and mod(A 6 6 )modA 6 0 . (Auth.)

Prevention measures for avoiding unexpected drifting of marine component in recovery equipment of significant metals from sea water. Positioning and monitoring system for marine component and improvement of its positioning accuracy

Energy Technology Data Exchange (ETDEWEB)

Tamada, Masao; Kasai, Noboru; Seko, Noriaki; Hasegawa, Shin; Takeda, Hayato; Katakai, Akio; Sugo, Takanobu [Japan Atomic Energy Research Inst., Takasaki, Gunma (Japan). Takasaki Radiation Chemistry Research Establishment; Kawabata, Yukiya [Ebara Reseach Co., Ltd., Fujisawa, Kanagawa (Japan); Onuma, Kenji [Mitsubishi Materials Corp., Tokyo (Japan)

2001-11-01

Positioning and monitoring system for marine component in recovery equipment of significant metals from seawater with adsorbent was designed and assembled to avoid unexpected drifting accident. This system which was set on float part of the marine component obtains the positioning data from GPS satellites and sends them to Takasaki and Mutsu establishments through satellite communication. In both establishments, the position data were shown in computer displays. As characteristic test for 20 days in the real sea, 262 data were obtained every 2 hours. The twice of the distance root mean square (2DRMS) was 223.7 m. To improve this performance, three new functions were added to the present firmware. There are to raise positioning resolutions in longitude and latitude from 0.001 to 0.00001 degree, to remove the reflection of GPS signal from sea surface, and to average remaining three positioning data after maximum and minimum data were omitted from continuous five positioning data. The improved system shows the 2DRMS positioning of 15.5 m. This performance is enough to prevent marine component from its drifting accident. (author)

Positive Psychology: Positive Emotions and Emotional Intelegence

OpenAIRE

Miloseva, Lence

2008-01-01

The paper focuses on the and emotional intelligence. We try to answer on some questions regarding the role which positive emotions have in our life’s. The broaden-and-build theory (Fredrickson, 1998; 2001) predicts that positive emotions are useful in several ways. They guide present behavior, by broadening one’s attention and cognition, setting the stage for creative, explorative, and innovative pursuits. As well, positive emotions build personal and social resources to help individuals achi...

A large community outbreak of gastroenteritis associated with consumption of drinking water contaminated by river water, Belgium, 2010.

Science.gov (United States)

Braeye, T; DE Schrijver, K; Wollants, E; van Ranst, M; Verhaegen, J

2015-03-01

SUMMARY On 6 December 2010 a fire in Hemiksem, Belgium, was extinguished by the fire brigade with both river water and tap water. Local physicians were asked to report all cases of gastroenteritis. We conducted a retrospective cohort study among 1000 randomly selected households. We performed a statistical and geospatial analysis. Human stool samples, tap water and river water were tested for pathogens. Of the 1185 persons living in the 528 responding households, 222 (18·7%) reported symptoms of gastroenteritis during the time period 6-13 December. Drinking tap water was significantly associated with an increased risk for gastroenteritis (relative risk 3·67, 95% confidence interval 2·86-4·70) as was place of residence. Campylobacter sp. (2/56), norovirus GI and GII (11/56), rotavirus (1/56) and Giardia lamblia (3/56) were detected in stool samples. Tap water samples tested positive for faecal indicator bacteria and protozoa. The results support the hypothesis that a point-source contamination of the tap water with river water was the cause of the multi-pathogen waterborne outbreak.

Sample intake position and loading rates from nonpoint source pollution

Science.gov (United States)

McGuire, P. E.; Daniel, T. C.; Stoffel, D.; Andraski, B.

1980-01-01

Paired water samples were simultaneously activated from two different vertical positions within the approach section of a flow-control structure to determine the effect of sample intake position on nonpoint runoff parameter concentrations and subsequent event loads. Suspended solids (SS), total phosphorus (TP) and organic plus exchangeable nitrogen [(Or+Ex)-N] were consistently higher throughout each runoff event when sampled from the floor of the approach section as opposed to those samples taken at midstage. Dissolved molybdate reactive phosphorus (DMRP) and ammonium (NH4-N) concentrations did not appear to be significantly affected by the vertical difference in intake position. However, the nitrate plus nitrite nitrogen [(NO3+NO2)-N] concentrations were much higher when sampled from the midstage position. Although the concentration differences between the two methods were not appreciable, when evaluated in terms of event loads, discrepancies were evident for all parameters. Midstage sampling produced event loads for SS, TP, (Or + Ex)-N, DMRP, NH4-N, and (NO3+NO2)-N that were 44,39,35,80,71, and 181%, respectively, of floor sampling loads. Differences in loads between the two methods are attributed to the midstage position, sampling less of the bed load. The correct position will depend on the objective; however, such differences should be recognized during the design phase of the monitoring program.

Water Quality Monitoring of Inland Waters using Meris data

Science.gov (United States)

Potes, M.; Costa, M. J.; Salgado, R.; Le Moigne, P.

2012-04-01

The successful launch of ENVISAT in March 2002 has given a great opportunity to understand the optical changes of water surfaces, including inland waters such as lakes and reservoirs, through the use of the Medium Resolution Imaging Spectrometer (MERIS). The potential of this instrument to describe variations of optically active substances has been examined in the Alqueva reservoir, located in the south of Portugal, where satellite spectral radiances are corrected for the atmospheric effects to obtain the surface spectral reflectance. In order to validate this spectral reflectance, several field campaigns were carried out, with a portable spectroradiometer, during the satellite overpass. The retrieved lake surface spectral reflectance was combined with limnological laboratory data and with the resulting algorithms, spatial maps of biological quantities and turbidity were obtained, allowing for the monitoring of these water quality indicators. In the framework of the recent THAUMEX 2011 field campaign performed in Thau lagoon (southeast of France) in-water radiation, surface irradiation and reflectance measurements were taken with a portable spectrometer in order to test the methodology described above. At the same time, water samples were collected for laboratory analysis. The two cases present different results related to the geographic position, water composition, environment, resources exploration, etc. Acknowledgements This work is financed through FCT grant SFRH/BD/45577/2008 and through FEDER (Programa Operacional Factores de Competitividade - COMPETE) and National funding through FCT - Fundação para a Ciência e a Tecnologia in the framework of projects FCOMP-01-0124-FEDER-007122 (PTDC / CTE-ATM / 65307 / 2006) and FCOMP-01-0124-FEDER-009303 (PTDC/CTE-ATM/102142/2008). Image data has been provided by ESA in the frame of ENVISAT projects AOPT-2423 and AOPT-2357. We thank AERONET investigators for their effort in establishing and maintaining Évora AERONET

Controls on facies and sequence stratigraphy of an upper Miocene carbonate ramp and platform, Melilla basin, NE Morocco

Science.gov (United States)

Cunningham, K.J.; Collins, Luke S.

2002-01-01

Upwelling of cool seawater, paleoceanographic circulation, paleoclimate, local tectonics and relative sea-level change controlled the lithofacies and sequence stratigraphy of a carbonate ramp and overlying platform that are part of a temporally well constrained carbonate complex in the Melilla basin, northeastern Morocco. At Melilla, from oldest to youngest, a third-order depositional sequence within the carbonate complex contains (1) a retrogradational, transgressive, warm temperate-type rhodalgal ramp; (2) an early highstand, progradational, bioclastic platform composed mainly of a temperate-type, bivalve-rich molechfor facies; and (3) late highstand, progradational to downstepping, subtropical/tropical-type chlorozoan fringing Porites reefs. The change from rhodalgal ramp to molechfor platform occurred at 7.0??0.14 Ma near the Tortonian/Messinian boundary. During a late stage in the development of the bioclastic platform a transition from temperate-type molechfor facies to subtropical/tropical-type chlorozoan facies occurred and is bracketed by chron 3An.2n (??? 6.3-6.6 Ma). Comparison to a well-dated carbonate complex in southeastern Spain at Cabo de Gata suggests that upwelling of cool seawater influenced production of temperate-type limestone within the ramp and platform at Melilla during postulated late Tortonian-early Messinian subtropical/tropical paleoclimatic conditions in the western Paleo-Mediterranean region. The upwelling of cool seawater across the bioclastic platform at Melilla could be related to the beginning of 'siphoning' of deep, cold Atlantic waters into the Paleo-Mediterranean Sea at 7.17 Ma. The facies change within the bioclastic platform from molechfor to chlorozoan facies may be coincident with a reduction of the siphoning of Atlantic waters and the end of upwelling at Melilla during chron 3An.2n. The ramp contains one retrogradational parasequence and the bioclastic platform three progradational parasequences. Minor erosional surfaces

Bio-corrosion of water pipeline by sulphate-reducing bacteria in a ...

African Journals Online (AJOL)

This study investigates the presence of SRB in water, in a water pipeline and in the soil near the pipeline at a mining operation, under conditions that would be expected to be stable toward corrosion. Samples of water in pipes showed a high frequency of SRB. Cast iron coupons placed in pipes gave positive results for SRB ...

Private well/spring position paper, Rifle, Colorado, sites

International Nuclear Information System (INIS)

1995-05-01

This report describes the hydrogeochemical relationship between the New and Old Rifle processing sites and 15 domestic wells in their vicinity. The relationship of the domestic wells to the Old and New Rifle tailings sites requires clarification due to recent advances in understanding of Rifle site conceptual models. In order to form a bridge from the Rifle remedial action plan (RAP) and the recent baseline risk assessment to this position paper, several issues require discussion. First, through analysis of long-term ground water level data, the hydraulic gradient between the former tailings and private wells and springs was assessed. Second, in the Rifle RAP there was not a strong emphasis placed on describing regional influences on water quality in the vicinity of the processing sites. This document uses available information coupled with theory of regional ground water flow to describe regional flow systems north of Rifle. Third, the definition of background water quality from the RAP has been refined in several ways. Also, for the recent baseline risk assessment, all alluvial wells used to define background for the sites were located east of Old Rifle. In the RAP, alluvial background wells were also placed between the sites (downgradient of Old Rifle). Two additional wells were installed for the recent baseline risk assessment upgradient of Old Rifle which verified that several of the older wells (RFO-01-0597 and -0598) were in locations representative of background

Want Positive Behavior? Use Positive Language

Science.gov (United States)

Wood, Chip; Freeman-Loftis, Babs

2012-01-01

Positive adult language is the professional use of words and tone of voice to enable students to learn in an engaged, active way. This includes learning social skills. To guide children toward choosing and maintaining positive behaviors, adults need to carefully choose the words and tone of voice used when speaking to them. Learning to use…

Discriminating binding and positioning of amphiphiles to lipid bilayers by {sup 1}H NMR

Energy Technology Data Exchange (ETDEWEB)

Evanics, F. [Department of Chemistry, University of Toronto, UTM, 3359 Mississauga Rd. North Mississauga, Ont., L5L 1C6 (Canada); Prosser, R.S. [Department of Chemistry, University of Toronto, UTM, 3359 Mississauga Rd. North Mississauga, Ont., L5L 1C6 (Canada)]. E-mail: sprosser@utm.utoronto.ca

2005-04-04

The binding and positioning in lipid bilayers of three well-known drugs--imipramine, nicotine, and caffeine--have been studied using {sup 1}H NMR. The membrane model system consisted of 'fast-tumbling' lipid bicelles, in which a bilayered lipid domain, composed of the unsaturated lipid, 1,2-dimyristelaidoyl-sn-glycero-3-phosphocholine (DMLPC) was surrounded by a rim of deuterated detergent-like lipids, consisting of 1,2-dihexanoyl-sn-glycero-3-phosphocholine (DHPC-d22). Binding and immersion depth information was obtained by three experiments. (1) {sup 1}H chemical shift perturbations, upon transfer of the amphiphiles from water to a bicelle mixture, were used to estimate regions of the amphiphiles that interact with the membrane. (2) Water contact to resolvable protons was measured through a Nuclear Overhauser Effect (NOE) between water and resolvable drug and lipid resonances. In the case of both lipids and membrane bound drugs, positive NOEs with large cross-relaxation rates were measured for most resonances originating from the membrane hydrophilic region, while negative NOEs were observed predominantly to resonances in the hydrophobic region of the membrane. (3) {sup 1}H NMR measurements of oxygen-induced (paramagnetic) spin-lattice relaxation rates, which are known to increase with membrane immersion depth, were used to corroborate conclusions based on chemical shift perturbations and water-ligand NOEs.

Visible laser induced positive ion emissions from NaCl nanoparticles prepared by droplet rapid drying

International Nuclear Information System (INIS)

Sun, Mao-Xu; Guo, Deng-Zhu; Xing, Ying-Jie; Zhang, Geng-Min

2012-01-01

Highlights: ► NaCl nanoparticles were firstly prepared by heat induced explosion on silicon wafer. ► We found that laser induced ion emissions from NaCl nanoparticles are more prominent. ► We found that water adsorption can efficiently enhance laser induced ion emissions. ► The ultra-photothermal effect in NaCl nanoparticles was observed and explained. - Abstract: A novel convenient way for the formation of sodium chloride (NaCl) nanoparticles on silicon wafer is proposed by using a droplet rapid drying method. The laser induced positive ion emissions from NaCl nanoparticles with and without water treatment is demonstrated by using a laser desorption/ionization time-of-flight mass spectrometer, with laser intensity well below the plasma formation threshold. It is found that the positive ion emissions from NaCl nanoparticles are obviously higher than that from microsize NaCl particles under soft 532 nm laser irradiations, and water adsorption can efficiently enhance the ion emissions from NaCl nanoparticles. The initial kinetic energies of the emitted ions are estimated as 16–17 eV. The synergy of the ultra-thermal effect in nanomaterials, the defect-mediated multiphoton processes, and the existence of intermediate states in NaCl-water interfaces are suggested as the mechanisms.

Temporal variation in the ecology of Kuramo water, Lagos Nigeria ...

African Journals Online (AJOL)

Temporal variation in the ecology of Kuramo water was studied in the Lagos lagoon complex. Physicochemical parameters and heavy metals concentration were analyzed. Eight sites were marked using the geographical positioning system (GPS model-12). Water chemistry was determined for 8 months and sampling was ...

Triple dividends of water consumption charges in South Africa

Science.gov (United States)

Letsoalo, Anthony; Blignaut, James; de Wet, Theuns; de Wit, Martin; Hess, Sebastiaan; Tol, Richard S. J.; van Heerden, Jan

2007-05-01

The South African government is exploring ways to address water scarcity problems by introducing a water resource management charge on the quantity of water used in sectors such as irrigated agriculture, mining, and forestry. It is expected that a more efficient water allocation, lower use, and a positive impact on poverty can be achieved. This paper reports on the validity of these claims by applying a computable general equilibrium model to analyze the triple dividend of water consumption charges in South Africa: reduced water use, more rapid economic growth, and a more equal income distribution. It is shown that an appropriate budget-neutral combination of water charges, particularly on irrigated agriculture and coal mining, and reduced indirect taxes, particularly on food, would yield triple dividends, that is, less water use, more growth, and less poverty.

A improved tidal method without water level

Science.gov (United States)

Luo, xiaowen

2017-04-01

Now most tide are obtained use water Level and pressure type water gage, but it is difficult to install them and reading is in low accuracy in this method . In view of above-mentioned facts, In order to improve tide accuracy, A improved method is introduced.sea level is obtained in given time using high-precision GNSS buoy combined instantaneous position from pressure gage. two steps are as following, (1) the GNSS time service is used as the source of synchronization reference in tidal measurement; (2) centimeter-level sea surface positions are obtained in real time using difference GNSS The improved method used in seafloor topography survey，in 145 cross points, 95% meet the requirements of the Hydrographic survey specification. It is effective method to obtain higher accuracy tide.

The role of hydrophobic interactions in positioning of peripheral proteins in membranes

Directory of Open Access Journals (Sweden)

Lomize Mikhail A

2007-06-01

Full Text Available Abstract Background Three-dimensional (3D structures of numerous peripheral membrane proteins have been determined. Biological activity, stability, and conformations of these proteins depend on their spatial positions with respect to the lipid bilayer. However, these positions are usually undetermined. Results We report the first large-scale computational study of monotopic/peripheral proteins with known 3D structures. The optimal translational and rotational positions of 476 proteins are determined by minimizing energy of protein transfer from water to the lipid bilayer, which is approximated by a hydrocarbon slab with a decadiene-like polarity and interfacial regions characterized by water-permeation profiles. Predicted membrane-binding sites, protein tilt angles and membrane penetration depths are consistent with spin-labeling, chemical modification, fluorescence, NMR, mutagenesis, and other experimental studies of 53 peripheral proteins and peptides. Experimental membrane binding affinities of peripheral proteins were reproduced in cases that did not involve a helix-coil transition, specific binding of lipids, or a predominantly electrostatic association. Coordinates of all examined peripheral proteins and peptides with the calculated hydrophobic membrane boundaries, subcellular localization, topology, structural classification, and experimental references are available through the Orientations of Proteins in Membranes (OPM database. Conclusion Positions of diverse peripheral proteins and peptides in the lipid bilayer can be accurately predicted using their 3D structures that represent a proper membrane-bound conformation and oligomeric state, and have membrane binding elements present. The success of the implicit solvation model suggests that hydrophobic interactions are usually sufficient to determine the spatial position of a protein in the membrane, even when electrostatic interactions or specific binding of lipids are substantial. Our