The effects of orthovanadate on the uptake of sucrose by Ricinus cotyledons and on sucrose-coupled proton influx were measured in order to gain insight into the relationship to the plasma membrane protonpump. Vanadate had no effect on short-term sucrose uptake. In long-term experiments (> 30 min) sucrose uptake was progressively inhibited, but only at high external sucrose concentrations. Vanadate did not affect proton efflux pumping in the absence of sucrose and neither did it change the initial rate of sucrose-coupled proton influx. However, it enhanced the maximal level of sucrose-induced alkalization of the medium at all sucrose concentrations tested. This is interpreted as an inhibiting effect of vanadate on the protonpump that recycles protons during sucrose-proton ...
Peptic ulcer bleeding is a common disease and recurrent bleeding is an independent risk factor of mortality. Infusion with protonpump inhibitors (PPIs) prevents recurrent bleeding after successful...Full Text Available
Homologous to bacteriorhodopsin and even more to proteorhodopsin, xanthorhodopsin is a light-driven protonpump that, in addition to retinal, contains a noncovalently bound carotenoid with a function...Full Text Available
The ntpJ gene, a cistron located at the tail end of the vacuolar-type Na+-ATPase (ntp) operon of Enterococcus hirae, encodes a transporter...Full Text Available
The responses of the vacuolar membrane (tonoplast) proton-pumping inorganic pyrophosphatase (H+-PPase) from oat (Avena sativa L.) roots to changes in Mg2+ and...Full Text Available
In an attempt to establish a relationship between protonpumping and the photocycle intermediates of bacteriorhodopsin, we have studied the effects of pH and temperature of flash-induced protonpumping and the photointermediates O/sub 640/ and M/sub 412/. The relative quantum yield of flash-induced protonpumping is both pH and temperature dependent. It is high in the acid pH range and at low temperatures but decreases in the basic pH range and at high temperatures. The decay of M/sub 412/ is biphasic. The amplitude of the slowly decaying component (M/sup s/) was found to be pH dependent with a pK similar to that of the ..delta..pH. The pH dependence of the fast-decaying component (M/sup f/) is opposite to that of M/sup s/ and ..delta..pH. Like that of M/sup s/, the amplitude of O/sub 640/ is high in the acid pH range, but unlike the amplitude of M/sup s/, it ...
Fourier transform infrared (FTIR) difference spectra have been obtained for the bR----K, bR----L, and bR----M photoreactions in bacteriorhodopsin mutants in which Asp residues 85, 96, 115, and 212 have been replaced by Asn and by Glu. Difference peaks that had previously been attributed to Asp COOH groups on the basis of isotopic labeling were absent or shifted in these mutants. In general, each COOH peak was affected strongly by mutation at only one of the four residues. Thus, it was possible to assign each peak tentatively to a particular Asp. From these assignments, a model for the proton-pumping mechanism of bR is derived, which features proton transfers among Asp-85, -96, and -212, the chromophore Schiff base, and other ionizable groups within the protein. The model can explain the observed COOH peaks in the FTIR difference spectra of bR photointermediates and could also account for other recent results on site-directed mutants of bR.
The authors report that the replacement of Leu-93 in bacteriorhodopsin by Ala (L93A) or Thr (L93T) slows down the photocycle by approximately 100-fold relative to wild-type bacteriorhodopsin. Time-resolved visible absorption spectroscopy and resonance Raman experiments, respectively, show the presence of long-lived O-like and N-like intermediates in the photocycles of the above mutants. We infer the existence of an equilibrium between the N and O intermediates in the photocycles of these mutants. The L93A and L93T mutants exhibit normal protonpumping under continuous illumination, suggesting that the decay of the N and/or O intermediate, and consequently, proton translocation, can be accelerated by the absorption of a second photon. Since the 13-cis----all-trans reisomerization of retinal is completed during the decay of the N and O intermediates, they conclude that the interaction of Leu-93 with retinal is important in ...
OAK B188 The goal of this project is to mimic the energy transduction processes by which photosynthetic organisms harvest sunlight and convert it to forms of energy that are more easily used and stored. The results may lead to new technologies for solar energy harvesting based on the natural photosynthetic process. They may also enrich our understanding and control of photosynthesis in living organisms, and lead to methods for increasing natural biomass production, carbon dioxide removal, and oxygen generation. In our work to date, we have learned how to make synthetic antenna and reaction center molecules that absorb light and undergo photoinduced electron transfer to generate long-lived, energetic charge-separated states. We have assembled a prototype system in which artificial reaction centers are inserted into liposomes (artificial cell-like constructs), where they carry out light-driven transmembrane translocation of hydrogen ions to generate proton motive ...
BACKGROUND: Epinephrine injection is the most common endoscopic therapy for peptic ulcer bleeding. Controversy exists concerning the optimal dose of protonpump inhibitors (PPI) for patients with bleeding peptic ulcers after successful endoscopic therapy. The objective of this study was to determine the optimal dose of PPI after successful endoscopic epinephrine injection in patients with bleeding peptic ulcers. METHODS: A total of 200 peptic ulcer patients with active bleeding or nonbleeding visible vessels (NBVV) who had obtained initial hemostasis with endoscopic injection of epinephrine were randomized to receive omeprazole 40 mg infusion every 6 h, omeprazole 40 mg infusion every 12 h or cimetidine (CIM) 400 mg infusion every 12 h. Outcomes were checked at 14 days after enrollment. RE...
Protonpump inhibitors are highly successful in treating gastroesophageal reflux disease, but a significant proportion of patients have persistent symptoms from weakly or nonacidic reflux. Transient lower esophageal sphincter relaxation (TLESR) represents the dominant mechanism of gastroesophageal reflux and has therefore become the most intensely investigated therapeutic target. The triggering of TLESR involve the vagal pathways and the ?-aminobutyric type B (GABA(B)) and metabotropic glutamate type 5 (mGluR5) receptors. Baclofen is a GABA(B) receptor agonist that is effective in inhibiting TLESR and reducing the number of reflux episodes, but is associated with significant central nervous system (CNS) side effects. The newer GABA(B) agonists, such as AZD9343 and AZD3355, and mGluR5 antag...
A fluidic pump comprises a two-diode pump having a first displacement vessel, a third diode connected to receive output from the two-diode pump through a delivery line and discharge to an outlet, and a second displacement vessel connected to the delivery line. There is a feed tank at a greater height than the two-diode pump, and a drive unit for alternately pressurising and venting the first and second displacement vessels. The drive pressure required to operate the pump can be of the order of half that for a single stage 2-diode pump. (author).
... Treatment of electrical systems for pumped storage plants is not covered in the manual, although much of the information is applicable to pumped ...
The invention deals with a pumping plant for oil filled power cables. An air driven piston type pump is used as primary pump. A PLS (Programmable Logic control System) is used to control the oil flow to the cable(s). Improvements of the pump includes means for ensuring that the pump piston is operated also at low pressure and flow, and means for sealing off the piston rod to ensure maximum life of seals, to facilitate detection of possible leakages and to avoid contamination of the cable oil. 3 figs.
Visual excitation is initiated by the absorption of a photon by the 11-cis retinal chromophore bound within the pigment called rhodopsin. We have used a variety of vibrational spectroscopies to obtain information about the vibrational nuclear dynamics that lead to this efficient photochemical isomerization. The cis-trans isomerization in rhodopsin is complete in only 200 fs. The extreme speed of this process, which is consistent with the {approximately}50 fs lifetime indicated by the spontaneous emission yield, suggests that the photochemistry involves non-stationary states or vibrational coherence. Recent studies have in fact observed vibrationally coherent oscillations of the ground state photoproduct called bathorhodopsin following impulsive excitation of the rhodopsin reactant. This conclusively demonstrates that the isomerization process in rhodopsin is vibrationally coherent. These observations further suggest that the isomerization quantum yield is directly dependent on the ...
Abstract in english Cell death is preceded by severe disruption of inorganic ion homeostasis. Seconds to minutes after an injury, calcium, protons, sodium, potassium and chloride are exchanged between the cell and its environment. Simultaneously, ions are shifted between membrane compartments inside the cell, whereby mitochondria and endoplasmic reticulum play a crucial role. Depending of the type and severity of injury, two mutually exclusive metastable states can be reached, which predict (more) the final outcome. Cells characterized by large increases in cytosolic [Ca2+], [Na+]; and [Mg2+] swell and die by necrosis; alternatively, cells characterized by high [H+]and low [K+], with normal [Na+] and normal to moderate [Ca2+] increases die by apoptosis. The levels of these ions represent central determinants in signaling events leading to cell death. Their movements are explained mechanistically by specific modulation of membrane transport proteins including ...
The strategies employed by oral streptococci to resist the inimical influences of acidification reflect the diverse and dynamic niches of the human mouth. All of the oral streptococci are capable of rapid degradation of sugar to acidic end-products. As a result, the pH value of their immediate environment can plummet to levels where glycolysis and growth cease. At this point, the approaches for survival in acid separate the organisms. Streptococcus mutans, for example, relies on its F-ATPase, to protect itself from acidification by pumpingprotons out of the cells. S. salivarius responds by degrading urea to ammonia and S. sanguis produces ammonia by arginolysis. The mechanisms by which these organisms regulate their particular escape route are now being explored experimentally. The picture that emerges is that the acid-adaptive regulatory mechanisms of the oral streptococci differ markedly from those employed by Gram-negative bacteria. What ...
Beside sucker-rod-type pumps and submersible centrifugal pumps, excentric screw pumps (so-called progressing cavity pumps) belong to standard conveyors in the production of crude oil. The authors of the contribution under consideration present the further development of excentric screw pumps with respect to the reduction of fluid levels in gas wells. This further development is based on a co-operation between the operator (Rohoel Aufsuchungs AG (Gampern, Austria)), the pump supplier (NETZSCH Oilfield Products GmbH (Selb, Federal Republic of Germany)) and the Institute for Process Technologies and Machinery at the University of Erlangen-Nuernberg (Federal Republic of Germany). The authors report on first attempts with the excentric screw pump at Weizberg (Federal Republic of Germany), material investigations at the University of ...
Charge-charge interactions dramatically influence the dissociation and proton transfer reactivity of large multiply protonated ions. In combination with tandem mass spectrometry, proton transfer...Full Text Available
Several compact proton accelerator systems for use in proton therapy have recently been proposed. Of paramount importance to the development of such an accelerator system is the maximum kinetic energy...Full Text Available
A growing number of pumped storage plants installed within the US brings attention to the increasing significance of pumped storage as a source of electrical generation capacity. Because of the special benefits this technology has to offer, hydroelectric pumped storage is an option that many utilities should consider for the supply of new capacity requirements. This article surveys the development and use of pumped storage in the US, and considers the potential for the future development of this technology. Although some of the problems that have occurred on recent projects highlight the role of pumped storage as a technological proving ground, the article puts forth the view that pumped storage is maturing to play a significant role in US electricity supply.
This booklet outlines the position of Manitoba's heat pump market with the objective of promoting the widespread use of geothermal heat pumps in the province. It makes reference to the size of the market, customer satisfaction with heat pumps, and opinion of key players in the industry regarding the heat pump market. The information in this booklet is drawn on market research and lessons learned in Europe and the United States. In October 2001, a group of key stakeholders in Manitoba's heat pump market attended an industry working meeting to address the issues of market barriers, market enablers and market hot buttons. Market barriers include the high cost of geothermal heat pumps, lack of consumer awareness, lack of consistent standards, and public perception that heat pumps are not reliable. Market enablers include the low and stable ...
My assignment on the SP-100 Vacuum Vessel Vacuum System Team was to perform a transient pump down analysis for the vacuum vessel that will house the SP-100 reactor during testing. Pump down time was calculated for air and helium. For all cases the proposed vacuum system will be able to pump down the vessel within the required time. The use of a larger rotary piston pump (DUO250) improves the pump down time by 35 minutes and therefore should be considered. The 6-inch duct for the roughing line is optimal, however, because all cases are well below the 24 hour time frame, the 4-inch duct is sufficient. The use of the single turbomolecular pump during pump down is sufficient. A pump down with helium in the vessel and a helium inleakage delays the time to achieve the base pressure marginally and is acceptable.
Slurry characteristics have a significant impact on centrifugal pump performance. For instance, as particle size increases or the percent solids concentration increases, pump head and efficiency decrease. Therefore, before a slurry pump is selected, it is important to define the slurry characteristics as accurately as possible. The effect of the slurry characteristics on the head and efficiency of the centrifugal pump will be emphasized (the effect on flowrate is less significant). The effect of slurry characteristics is more predominant in smaller pumps (with smaller diameter impellers) than in larger pumps. The data and relationship between the various slurry parameters have been developed from correlations and nomographs published by pump vendors from their field data and test results. The information helps to avoid specifying an ...
The authors propose an integrated indicator of pump-rod couplings that allows both the couplings and the pump operations to be appraised according to the given formula. (Formula provided). The dynamic relationships of rod operations were determined with nomographs. These relationships involve such factors as: the type and size of the sucker-rod string; the pressure load at the equalizer head and its correlation to threshold pressure at pump discharge; pump diameter; the rod weight and construction; and integral reliability indicators.
Limestone slurry needs to move efficiently through a complex process, meaning that selecting the right pumps and valves is critical. The article discusses factors to consider in selecting pumps and values for flue gas desulfurization process in coal-fired power plants. 2 photos.
This paper describes the advent of energy pumped storage plants in France, in connection with nuclear power reactors development and gives detailed specifications of different components (pump turbines, alternators, valves ...). 5 figs., 3 tabs.
In order to reduce the length and to increase the effectiveness of processing, the proposed method for acetic processing of an electric centrifugal well pump calls for covering the pressure line during the curing and periodically starting the pump.
The recent measurements by the BES Collaboration of J/psi decays into a photon and a proton-antiproton pair indicate a strong enhancement at the proton-antiproton threshold not observed in the decays into a neutral pion and a proton-antiproton pair. Is this enhancement due to a proton-antiproton quasi-bound state or a baryonium? A natural explanation follows from a traditional model of proton-antiproton interactions based on G-parity transformation. The observed proton-antiproton structure is due to a strong attraction in the 1S0 state, and possibly to a near-threshold quasi-bound state in the 11S0 wave.
Using the past diffusion trends of four renewable energy technologies for irrigation water pumping in India (SPV pumps, windmill pumps and biogas/producer gas driven dual fuel engine pumps), results of an attempt to project their future dissemination levels, have been presented in this study. The likely contribution of the renewable energy options considered in the study to the projected energy demand for irrigation water pumping in India has been estimated. Estimates of the associated investment requirements taking into account the learning effect have also been presented. (author)
The purpose of the chapter is to explain briefly the various considerations that enter into determining the general layout or arrangement of typical hydroelectric powerplants, pumping plants, and pumped-storage plants. Some of the important factors that affect or determine the location, type, and layout of the plant and the selection of the major items of equipment included in the installation are outlined in this chapter. The first consideration in the design of a powerplant, pumping plant, or pumped-storage plant is that it adequately perform its function and be structurally safe. The structure is also designed to give a pleasing architectural appearance.
The advantages of using heads of around 1000 m in conjunction with underground location of the lower reservoirs for pumped storage plants are described, and the possible layouts, equipment, and construction methods are discussed.
The installation and performance of a water source heat pump in Minnesota are discussed. The operating cost was found to be higher than expected. (MHR)
Simple frameworks have been developed for estimating the utilization potential of: (a) solar photovoltaic (SPV) pumps; (b) windmill pumps; (c) producer gas based dual fuel engine pumps; and (d) biogas based dual fuel engine pumps for irrigation water pumping in India. The approach takes into account factors such as: solar radiation intensity, wind speed, availability of bovine dung and agri-residues, and their alternative uses, ground water requirements for irrigation and its availability, affordability, and propensity of the users to invest in renewable energy devices, etc. SPV pumps are estimated to have the maximum utilization potential in India, followed by windmill pumps. (author)
pumped storage plants; but these must be built as well since there is no correspondence with the pump and turbine operating times governed by normal network ...
We will examine modeling data for various orbits using modeling software and compare this with actual satellite flight result. In particular, we will discuss the contributions of trapped protons to total dose and the effectiveness of shielding.
A new double-null, slotted divertor configuration will be installed for the DIII-D Radiative Divertor Program at General Atomics in late 1996. Four cryocondensation pumps, three new and one existing, will be part of this new divertor. The purpose of the pumps is to provide plasma density control and to limit the impurities entering the plasma core by providing pumping at each divertor strike point. The three new pumps are based on the design of the existing pump, installed in 1992 as part of the Advanced Divertor Program. The pump continues to operate successfully. The new pumps require geometry modifications to the original design. Therefore, extensive modal and dynamic analyses were performed to determine the behavior of these pumps and their helium and nitrogen feed lines during disruption events. Thermal and fluid ...
A new double-null, slotted divertor configuration will be installed for the DIII-D Radiative Divertor Program at General Atomics in late 1996. Four cryocondensation pumps, three new and one existing, will be part of this new divertor. The purpose of the pumps is to provide plasma density control and to limit the impurities entering the plasma core by providing pumping at each divertor strike point. The three new pumps are based on the design of the existing pump, installed in 1992 as part of the Advanced Divertor Program. The pump continues to operate successfully. The new pumps require geometry modifications to the original design. Therefore, extensive modal and dynamic analyses were performed to determine the behavior of these pumps and their helium and nitrogen feed lines during disruption events. Thermal and fluid ...
This technical report describes an outline, features, total energy efficiency, and specifications of binary heat pump system. A closed circuit distributed water heat source heat pump method is employed in the binary heat pump system. Since the circulating water, which is adjusted at a constant temperature, is used as the heat source of the indoor unit, a stable performance can be obtained regardless of outside atmospheric temperature. The binary heat pump system is mainly composed of a center heat pump unit, indoor heat pump unit, heat source water pipes, and circulating pump. The center heat pump unit and the indoor heat pump unit are connected with each other by the heat source water, and each unit can be operated independently. This system is characterized by the simultaneous operation of cooling ...
The main subject of this thesis is the study of the hardronic final state in deep-inelastic electron-proton scattering. Theexperiment described in this thesis is performed with such a high resolution that the substructure of the proton is probed by the electron beam with a resolution of less than 10{sup -15} cm. (orig./HSI).
A balanced application of chemiosmosis to plant mitochondria is presented. Electron transport carriers are sequenced to achieve proton translocation across the inner membrane. The processes of proton translocation, use, and release are integrated to yield a description of the effective proton gradient available for metabolite transport and ATP synthesis. 27 references, 6 figures.
Cross section parameterizations for antiproton production in pp collisions are used to predict the antiproton/proton ratio resulting from a flux of cosmic protons with energy spectral index of 2.6 interacting with a 5 gm/cm/sup 2/ column density of H. (GHT)
The seawater in the intake structure flows into the large pump to with draw excess heat from the turbine steam condenser. In the intake structure of a nuclear power plant, undesirable pump operating characteristics such as vortices, impeller damages and non-uniform pump-approach flow around the pump bells take place frequently due to poorly-arranged intake geometry. In this study, physical modeling test was performed to predict the hydraulic phenomenon, and proposed flow control devices.
Due to their good hydraulic characteristic semi-axial pump turbines are used in the medium head range of pumped storage plants. This paper describes model tests performed on a semiaxial pump turbine model and shows the results of these tests. The aim of the model tests was the optimization of the hydraulic water passage, the measurement of the hydraulic characteristics over the whole operating range, the investigation of the cavitation behaviour, the investigation of the hydraulic forces and torques as well as the proof of the values guaranteed to the customer.
This 2001 edition of the guide to UK renewable energy companies examines the geothermal heat pump sector, and discusses the technology involved, installations of geothermal heat pumps, the activity in the UK market with increased interest in UK geothermal heat pump products from abroad, and developments in the building sector. The UK government's increased support for the industry including its sponsorship of the Affordable Warmth programme, and the future potential of ground source systems are discussed.
This 2001 edition of the guide to UK renewable energy companies examines the geothermal heat pump sector, and discusses the technology involved, installations of geothermal heat pumps, the activity in the UK market with increased interest in UK geothermal heat pump products from abroad, and developments in the building sector. The UK government's increased support for the industry including its sponsorship of the Affordable Warmth programme, and the future potential of ground source systems are discussed.
The theory of reliability is used to develop statistical field data on malfunctions of units of sucker rod well pumps (UShSN). The indices of reliability of the UShSN are applied for establishment of the cause-effect links between the operating factors. Dependences of operating time on the depth of suspension of the pumps, mode of pumping out, degree of flooding of the oil, and twisting of the shafts are established for conditions of specific fields. The obtained relationships can be used in selecting and optimizing the work of the UShSN.
A novel approach to the reliability analysis of a power system with both hydro and pumped storage plants is presented in this paper. The proposed method is based on the concept of peak shaving for the hydro and pumped storage units. Different values of the stored energy of the pumped storage units are employed to demonstrate their effect on the generation reliability of a power system. The proposed scheme has been applied successfully to the reliability analysis of Taiwan power system.
A new double-null, slotted divertor configuration will be installed for the DIII-D Radiative Divertor Program at General Atomics in late 1996. Four cryocondensation pumps, three new and one existing, will be part of this new divertor. The purpose of the pumps is to provide plasma density control and to limit the impurities entering the plasma core by providing pumping at each divertor strike point. The three new pumps are based on the design of the existing pump, installed in 1992 as part of the Advanced Divertor Program. The new pumps require geometry modifications to the original design. Therefore, extensive modal and dynamic analyses were performed to determine the behavior of these pumps and their helium and nitrogen feed lines during disruption events. Thermal and fluid analyses were also performed to characterize the helium two-phase ...
The design of the absorber blocks for internal and external dumping of the SPS proton beam is discussed. In addition, the external target stations for slow and fast extracted proton beams are described.
The authors present some recent measurements on electroweak physics using data collected by the CDF experiment at the Tevatron proton anti-proton collider ({radical}s = 1.96 TeV) at Fermilab.
PurposeTo determine the dosimetric impact of inter-fraction anatomical movements in prostate cancer patients receiving proton therapy.Full Text Available
Background"Nubiotics" are synthetic oligonucleotides and nucleotides with nuclease-resistant backbones, and are fully protonated for enhanced ability to be taken up by bacterial...Full Text Available
The influence of the main factors on device efficiency of pulsed liquid jet pump with gas-liquid piston is analysed, the theoretical equation and its time-averaged solution of pulsed liquid jet pump device efficiency are derived. The theoretical and experimental results show that the efficiency of transmission of energy and mass to use pulsed jet is greatly raised, compared with steady jet, in the same device of liquid jet pump. The calculating results of time-averaged efficiency of pulsed liquid jet pump are approximately in agreement with the experimental results in our and foreign countries
The general types of pumped-storage plants and considerations for determining their need, use, and selection are presented. A brief discussion of TVA's experience on two pumped-storage schemes is included. Pumped-storage plants have become an integral part of many hydropower systems. Most of these systems use pumped-storage plants to meet power requirements during the peak load demands. In any application, large or small, the expected load demand and supply source must be identified to select the best scheme required for the particular system.
This paper presents a new algorithm for the optimal long-range generation planning for a thermal system with pumped-storage plants. The algorithm is based upon the analytical production costing model developed under the assumption of Gaussian probabilistic distribution of random load fluctuations and plant outages. The optimization problem consists of the master problem to determine the annual investment, and the pumped-storage subproblem to determine the optimal pumped-storage operation. The master problem is formulated as a Hamiltonian minimization problem, and the pumped-storage subproblem is solved using the concept of peak-shaving operation on the original load curve.
This paper presents a new algorithm for the optimal long-range generation planning for a thermal system with pumped-storage plants. The algorithm is based upon the analytical production costing model developed under the assumption of Gaussian probabilistic distribution of random load fluctuations and plant outages. The optimization problem consists of the master problem to determine the annual investment, and the pumped-storage subproblem to determine the optimal pumped-storage operation. The master problem is formulated as a Hamiltonian minimization problem, and the pumped-storage subproblem is solved using the concept of peak-shaving operation on the original load curve.
The fastest rate of growth in the space conditioning market has been attributed to the application of geothermal heat pumps to the industrial and commercial markets. The author reviews and provides examples of the three most popular components of a large geothermal heat pump system: geothermal earth coupling, heat pumps and heat exchangers, and building side terminals. These components are applied to three example geothermal installations: a library, an office building, and a school. Examples of energy use before and after the installation of a geothermal space conditioning system are summarized. General design and cost guidelines and comments on the use of geothermal heat pump in these and similar applications are discussed.
In the development of a geothermal heat pump a water source heat pump was connected to a 1-1/2'' water line, 2200' long, buried in an endless loop 10' deep. The system is closed, circulating the same water continuously through the heat pump back to the field again. This water line 10' deep is the geothermal heat source. No matter how cold the air temperature gets on a winter day the water temperature to the heat pump will always be above 45/sup 0/F. This system has efficiently heated our house the past year using no supplemental heat.
The paper deals with the exploitation of the pumped storage plants for the control of the Slovak power system. For that purpose current utilization of pumped storage plants currently in operation was analyzed from the point of view of their part in the operation control of the Slovak power system. The aim of this analysis was to exploit knowledge gained so far for the future outlook up to the year 2010, including the evaluation of the need to construct pumped storage plant Ipel with a weekly storage cycle. (author).
The scope and contents investigate and reviewed are as follows : establishment of study plan and references survey, review of related problems and inservice test standards of safety injection pump in use nuclear power plant, review of the study results in laboratory, the theoretical investigation of temperature rise according to mini-flow rate of pump, mini-flow rate working characteristics of high and low pressure injection pumps at nuclear power plants, setup of testing equipment for measuring ampere, discharge pressure and vibration, selection and behaviors analysis of major parameters concerning pump degradation.
Two mechanical design requirements are defined for the SSC Collider beam tube. First, the vacuum requirement (luminosity lifetime = 150 hrs). It requires the design of a pressure boundary within the cold mass vessel to provide a vacuum tunnel for the proton beam and to minimize the synchrotron radiation gas desorbtion with a suitable material. The Collider beam tube design is under an intensive activity to search for a material that will meet the luminosity requirement without a distributed pump or liner. Second is the tube wall`s resistivity requirement ({sigma}*t = 2E5 {Omega}{sup {minus}1}). For a 4.2 K beam tube the Cu thickness is 100 {mu}m (RRR=30,6.7 T, {sigma}=2E9{Omega}{sup {minus}1}m{sup {minus}1}). The copper yield strength is relatively low in comparison to steel and, therefore, the design of the steel layer is governed by the copper layer yield stress limit. A beam tube subjected to eddy current load in a quenching dipole requires ...
Two mechanical design requirements are defined for the SSC Collider beam tube. First, the vacuum requirement (luminosity lifetime = 150 hrs). It requires the design of a pressure boundary within the cold mass vessel to provide a vacuum tunnel for the proton beam and to minimize the synchrotron radiation gas desorbtion with a suitable material. The Collider beam tube design is under an intensive activity to search for a material that will meet the luminosity requirement without a distributed pump or liner. Second is the tube wall's resistivity requirement ([sigma]*t = 2E5 [Omega][sup [minus]1]). For a 4.2 K beam tube the Cu thickness is 100 [mu]m (RRR=30,6.7 T, [sigma]=2E9[Omega][sup [minus]1]m[sup [minus]1]). The copper yield strength is relatively low in comparison to steel and, therefore, the design of the steel layer is governed by the copper layer yield stress limit. A beam tube subjected to eddy current load in a quenching dipole ...
We discuss the consequence of local duality for elastic scattering, and derive a model-independent equation between structure functions at x ? 1 and elastic electromagnetic form factors. Then the electromagnetic form factors of proton are discussed using the quark-hadron duality theory. We also debate the form factor of proton in a bound state. It may be an effective approach to study the form factor of proton in media.
The cross sections for proton-proton elastic scattering at Fermilab and ISR energies are investigated in the framework of the multiple constituent scattering formalism, including the contributions of the inelastic intermediate states. We find that the higher-order multiple scattering amplitudes are strongly suppressed due to the presence of the inelastic intermediate states. The calculated cross sections reproduce the high energy experimental data fairly well. (author).
Using ab initio (SCF/6-31G) method, mechanisms of proton migrations in methaboric acid dimers have studied. It is shown that in all the dimers considered a cooperative transfer of protons occurs. The calculated values of activation barriers of cooperative proton transfer reactions in the dimers are equal to 28.6 kcal/mol.
In earliest works devoted to proton computed tomography it was shown that the advantage of pCT image reconstruction appears when the energy is close to the Bragg peak region, since the proton passes the object. This effect provided by the Bragg peak makes the computerized tomography with protons possible. However, when decreasing the initial proton energy, with the increase of the irradiation dose, there are two effects that work simultaneously in opposite ways. First, the energy loss of a proton in an object becomes bigger at small initial energy. At the same time decreasing of the proton energy results in the increase of the energy straggling, requiring a larger number of protons. In this work the radiation dose dependence on the proton initial energy was studied using analytical formulas and computer simulations. The ...
In order to improve the measuring efficiency, a 'proton-gamma' coincidence technique in combination with a He-jet tape transport system was proposed and employed to identify the #beta#-delayed proton precursors. The study of #beta#-delayed proton decays near the proton drip line by using the 'proton-gamma' coincidence technique over the last 5 years at the Institute of Modern Physics, Lanzhou, China, was summarized. New #beta#-delayed proton precursors "1"2"1Ce, "1"2"5Nd, "1"2"8Pm, "1"2"9Sm, "1"3"5Gd, "1"3"7Gd, "1"3"9Dy, "1"4"2Ho, and "1"4"9Yb in the rare-earth region along a speculated proton drip line were synthesized and identified for the first time. The #beta#-delayed proton decays of "8"1Zr, "8"5Mo, "8"9Ru, and "9"3Pd in T_z=1/2 series as well as "9"2Rh in T_z=1 series were observed.
A pump down model for a vacuum chamber with a reversibly adsorbed phase is presented. The outgassing equation which predicts the variation of coverage at the wall surface of a vacuum chamber with time is derived. Then the measured and the true outgassing rates are defined. The theoretical measured outgassing rate shows only a very weak dependence for pumping speed. This prediction is opposite to the experimental result that the measured outgassing rate depends significantly on pumping speed. It is discussed that the experimental measured outgassing rate must be described as the product of the effective pumping speed and the measured pressure in the pumped chamber, in which the measured pressure is equivalent to the equilibrium pressure of the wall surface described by the equilibrium adsorption isotherm as a function of the shifted surface coverage {theta}-{delta}{theta} by a small ...
The Electric Power Research Institute has published a report for planners, designers, owners, and operators of hydroelectric pumped-storage plants that records the operation and maintenance knowledge of 35 domestic and foreign pumped-storage projects. The report provides a comprehensive record of practices that have reduced forced outages and shortened scheduled repairs. As time passes and experienced staff retire at pumped-storage plants, many O M lessons are lost. To remedy that situation, EPRI commissioned Morrison-Knudsen Engineers Inc. to prepare a special report. The 348-page publication records the accumulated civil, geotechnical, mechanical, and electrical O M knowledge and experiences of pumped-storage plant staff. It also includes recommendations to planners and designers of future pumped-storage plants and concludes with descriptions of O M experiences reported by plant ...
Purpose: To obtain stabilized operation by preventing over heat in emergency cooling pumps upon accidents of flow regulators. Constitution: A pressure suppression chamber pool and a pressure vessel are communicated to each other with a pipeway and the water in the suppression pool is charged by a charging pump to the pipeway. The pipeway is interposed with an emergency cooling pump so as to feed water in the pipeway to the pressure vessel and a water source and the emergency cooling pumps are connected by way of a closed pipeway. Further, the closed pipeway and the pipeway interposed with the charging pump are communicated to each other by way of a connecting pipeway, to which are interposed an instrument for detecting the increase in the temperature of the emergency cooling pumps due to abnormality in the closed pipe (such as troubles in flow regulators) and ...
To examine the hormonal regulation of the ATP-dependent Ca{sup 2+} pump in the kidneys, the ATP-dependent Ca{sup 2+} uptake by the basolateral membrane vesicles in the renal cortex was measured using radioactive calcium ({sup 45}Ca{sup 2+}) in rats with vitamin D deficiency or rats undergoing thyroparathyroidectomy. The V{sub max} of the Ca{sup 2+} pump activity was increased not only by administering calcitriol, but also by normalizing the serum calcium level in vitamin D-deficient rats. PTH suppressed the Ca{sup 2+} pump activity in normocalcemic vitamin D-deficient rats. Thyroparathyroidectomy did not affect the Ca{sup 2+} pump activity in the kidneys of normal rats. It was concluded that the ATP-dependent Ca{sup 2+} pump activity was depressed by secondary hyperparathyroidism in vitamin D-deficient rats. (author).
To examine the hormonal regulation of the ATP-dependent Ca"2"+ pump in the kidneys, the ATP-dependent Ca"2"+ uptake by the basolateral membrane vesicles in the renal cortex was measured using radioactive calcium ("4"5Ca"2"+) in rats with vitamin D deficiency or rats undergoing thyroparathyroidectomy. The V_m_a_x of the Ca"2"+ pump activity was increased not only by administering calcitriol, but also by normalizing the serum calcium level in vitamin D-deficient rats. PTH suppressed the Ca"2"+ pump activity in normocalcemic vitamin D-deficient rats. Thyroparathyroidectomy did not affect the Ca"2"+ pump activity in the kidneys of normal rats. It was concluded that the ATP-dependent Ca"2"+ pump activity was depressed by secondary hyperparathyroidism in vitamin D-deficient rats. (author).
This paper develops optimal bidding strategies for a pumped-storage plant in a pool-based electricity market. In the competitive regime, when compared to simple hydroelectric generator, profit of the pumped-storage plant is maximized by operating it as a generator when market clearing price is high and as a pump when the price is low. Based on forecasted hourly market clearing price, a multistage looping algorithm to maximize the profit of a pumped-storage plant is developed, considering both the spinning and non-spinning reserve bids and meeting the technical operating constraints of the plant. The proposed model is adaptive for the nonlinear three-dimensional relationship between the power produced, the energy stored, and the head of the associated reservoir. Different operating cycles for a realistic pumped-storage plant are considered and simulation results are reported and ...
This paper reports on hydroelectric pumped storage which is the only proven and most efficient technology available for energy storage. It is used by utilities to provide peak and intermediate power and to optimize overall system performance. Because of increased environmental and regulatory constraints, few acceptable sites, long schedules, and huge financial commitments, large conventional pumped storage plants, are now virtually impossible to build. As an alternative, small modular pumped storage, with project sizes ranging from 25 MW to 200 MW, was created to overcome the difficulties of conventional projects. The modular approach involves standardizing the elements of a pumped storage plant by utilizing specialized siting techniques and optimizing design, equipment, and construction. Compared with conventional pumped storage, the modular design can reduce cost and expedite ...
A HydroSele S seal from James Walker has provided more than two years maintenance-free service at the large Entracque pumped-storage hydroelectric scheme in Italy.
The Underground Hydroelectric Pumped Storage (UHPS) Program Plan describes in detail the planned activities and expected accomplishments in the conduct of UHPS technology development and validation envisioned in the 1976 to 1990 time frame. This document describes the program objectives, implementation strategy, and management methodology. The concept of underground hydroelectric pumped storage is fully directed to application in the electric utility industry. This technology involves using electrical energy generated by base-load plants during off-peak load periods to drive a high-head pump/turbine which pumps water from a lower reservoir to a substantially elevated (upper) reservoir corresponding to a head of 1000 m or so. The upper reservoir is at ground level and the lower reservoir is below ground. Then, during peak-load periods, water in the upper reservoir is allowed to flow to the lower ...
The computer program CNHSPM is listed which predicts heat pump seasonal energy consumption (including defrost, cyclic degradation, and supplementary heat) using steady state rating point performance and binned weather data. (LEW)
Nuclear power plant has several safety features and each safety feature is based on the operation of pumps and valves. Therefore, it is an essential basis for the safety of nuclear power plant to keep operational readiness of pumps and valves by In-Service Test (IST). According to Ministry of Education, Science and Technology (MEST) Bulletin 2008-14, the safety functioned pumps and valves of all nuclear power plants of Korea Hydro and Nuclear Power Co. Ltd.(KHNP) have been tested to verify their performance of safety function. Each safety grade pump has own design requirement and should be tested to identify whether it could meet the requirement. Design requirements and test references of all safety grade pumps of Wolsung Nuclear Power Plant Unit 2 (Wolsung Unit 2) were examined in this study. And the results of the performance test of the pump were also ...
Nuclear power plant has several safety features and each safety feature is based on the operation of pumps and valves. Therefore, it is an essential basis for the safety of nuclear power plant to keep operational readiness of pumps and valves by In-Service Test (IST). According to Ministry of Education, Science and Technology (MEST) Bulletin 2008-14, the safety functioned pumps and valves of all nuclear power plants of Korea Hydro and Nuclear Power Co. Ltd.(KHNP) have been tested to verify their performance of safety function. Each safety grade pump has own design requirement and should be tested to identify whether it could meet the requirement. Design requirements and test references of all safety grade pumps of Wolsung Nuclear Power Plant Unit 2 (Wolsung Unit 2) were examined in this study. And the results of the performance test of the pump were also ...
The article describes control and monitoring concepts in which the delegation of responsibility is becoming more decisive than ever (automation hierarchy), and which are capable of optimized, automatic control of process events in pumped storage plants. 8 refs.
Feb 24, 2000 ... NASA computer experts have been using a supercomputer to improve the NASA/ DeBakey miniature heart assist pump, leading to on-going human ...
Pumped storage plants 20 are a relatively common type.They use a dam to create an upper reservoir ...Some pumped storage plants use the same water turbine and electric generator for both operating periods.That is,
Pumped storage plants are a relatively common type.They use a dam to create an upper reservoir ...Some pumped storage plants use the same water turbine and electric generator for both operating periods.
Bolus infusion of insulin along with a meal is a standard procedure with continuous subcutaneous insulin infusion. Modern insulin pumps allow applying this bolus in four different ways: infusion of...Full Text Available
The alternative to the use of deeper wells through temperature amplification of the geothermal resource by electric heat pumps is explored. Systems in Ephrata, Washington and Chamberlain, South Dakota are explored. (MHR)
A method for recycling laser flashlamp radiation in selected wavelength ranges to decrease thermal loading of the solid state laser matrix while substantially maintaining the pumping efficiency of the flashlamp.
Many pump reliability problems in the Nuclear Power Plants (NPPs) are being attributed to the operation of the pump at flow rates well below its best efficiency point(BEP). Generally, the manufacturer and the user try to avert such problems by specifying a minimum flow, below which the pump should not be operated. Pump minimum flow usually involves two considerations. The first consideration is normally termed the 'thermal minimum flow', which is that flow required to prevent the fluid inside the pump from reaching saturation conditions. The other consideration is often referred to as 'mechanical minimum flow', which is that flow required to prevent mechanical damage. However, the criteria for specifying such a minimum flow are not clearly understood by all parties concerned. Also various factor and information for computing minimum flow are not easily available as considering for ...
BACKGROUNDOff-pump coronary artery bypass (OPCAB) surgery is associated with a hypercoagulable state in which the platelet thrombin receptor, protease-activated receptor-1...Full Text Available
Singlet oxygen generators are multiphase flow chemical reactors used to generate energetic oxygen to be used as a fuel for chemical oxygen iodine lasers. In this paper, a theoretical model of the generator is presented along with its solutions over ranges of parameter space and oxygen maximizing optimizations. The singlet oxygen generator (SOG) is a low-pressure, multiphase flow chemical reactor that is used to produce molecular oxygen in an electronically excited state, i.e. singlet delta oxygen. The primary product of the reactor, the energetic oxygen, is used in a stage immediately succeeding the SOG to dissociate and energize iodine. The gas mixture including the iodine is accelerated to a supersonic speed and lased. Thus the SOG is the fuel generator for the chemical oxygen iodine laser (COIL). The COIL has important application for both military purposes--it was developed by the US Air Force in the 1970s--and, as the infrared beam is readily absorbed by metals, industrial cutting ...
A thermodynamic analysis of a hybrid geothermal heat pump system is carried out. Mass, energy, and exergy balances are applied to the system, which has a cooling tower as a heat rejection unit, and system performance is evaluated in terms of coefficient of performance and exergy efficiency. The heating coefficient of performance for the overall system is found to be 5.34, while the corresponding exergy efficiency is 63.4%. The effect of ambient temperature on the exergy destruction and exergy efficiency is investigated for the system components. The results indicate that the performance of hybrid geothermal heat pump systems is superior to air-source heat pumps.
Due to changed operational conditions and because of the increasing age of several hydro power plant components, there is an increasing risk of damages and the control of degradation mechanisms is of increasing significance. Therefore lifetime considerations for safety relevant components in pumped-storage plants become more and more important. The development of a lifetime management system, in conjunction with monitoring systems and specific surveillance for a group of pumped-storage power plants of different ages and in a wide range of power output is presented. The special focus is on the impact of fatigue strength considerations within this framework. The applied procedure will be described for typical mechanical components in pumped-storage plants exemplarily. (orig.)
A detailed component-based simulation model of a geothermal heat pump system has been calibrated to monitored data taken from a family housing unit located at Fort Polk, Louisiana. The simulation model represents the housing unit, geothermal heat pump, ground heat exchanger, thermostat, blower, and ground-loop pump. Each of these component models was tuned to better match the measured data from the site. These tuned models were then interconnected to form the system model. The system model was then exercised in order to demonstrate its capabilities.
A detailed component-based simulation model of a geothermal heat pump system has been calibrated to monitored data taken from a family housing unit located at Fort Polk, Louisiana. The simulation model represents the housing unit, geothermal heat pump, ground heat exchanger, thermostat, blower, and ground-loop pump. Each of these component models was 'tuned' to better match the measured data from the site. These tuned models were then interconnect to form the system model. The system model was then exercised in order to demonatrate its capabilities.
Innovative new ideas for the construction of homes are described. A thermal energy storage system fireplace and a geothermal heat pump for homes are described.
Late 1994, the Geothermal Heat Pump Consortium (GHPC) was launched as a non-profit collaborative effort between the United States Department of Energy, US electric utilities and the GeoExchange (geothermal heat pump) industry to make ''geothermal heat pumps'' a significant component of the HVAC industry and avoid 1.5 million metric tons of carbon equivalent per year. The goal was to create a self-sustainable GeoExchange market. This report offers a summary of some of the lessons learned and an overview of some of the programs major accomplishments.
All power plant engineers face the problem of peak power demands. Pumped storage plants are used to generate peak load power by pumping up water utilizing off-peak energy of hydrothermal and thermonuclear plants. This is the first accessible text/reference to cover hydroelectric power generation with emphasis on engineering to meet peak power demands by means of pumped storge plants, tidal power plants, and low head power generation. Text covers hydrology, mechanical and electrical equipment, accessories such as penstocks and valves, and civil engineering considerations. Contains descriptions of several existing plants. Includes 200 diagrams and 50 photographs.
All power plant engineers face the problem of peak power demands. Pumped storage plants are used to generate peak load power by pumping up water utilizing off-peak energy of hydrothermal and thermonuclear plants. This is a reference to cover hydroelectric power generation with emphasis on engineering to meet peak power demands by means of pumped storage plants, tidal power plants, and low head power generation. Text covers hydrology, mechanical and electrical equipment, accessories such as penstocks and valves, and civil engineering considerations. Contains descriptions of several existing plants. Includes 200 diagrams and 50 photographs.
A back-up system is provided for a pumping plant or a pressure reservoir system used to maintain insulating oil under pressure in high voltage submarine power cables which includes a gas driven membrane pump to insure a small outflow of oil at a rupture point in the power cable to prevent water from penetrating the cable. The proper operation of the membrane pump is insured by introducing degasified oil at the drive side of the pump during the stand-by and test modes of operation of the back-up system. 11 drawings.
... Propulsive efficiency is equivalent to the product of thrust efficiency and the hull/waterjet interaction efficiency. ... t'waterjet pump Ktorque repeated ...
Steady-state and transient behavior of the longitudinally pumped semiconductor laser is theoretically investigated by using a rate-equation model with distributed gain and photon density. Conditions necessary for bistable operation are derived. Dependencies of such major switching characteristics as turn-on and turn-off powers, delay, and rise times on laser parameters are examined. Influences of spontaneous radiation, impurities, and Auger recombination are studied. The results offer an explanation for the observed nonlinear behavior of face-pumped lasers.
This sheet summarizes information on geothermal heat pumps (GHPs), which extracts heat from the ground in the winter and transfers heat to the ground in the summer. More than 200,000 GHPs are operating in US; they can reduce energy consumption and related emissions by 23 to 44% compared to air-source heat pumps. Opportunities for use of GHPs, requirements, and cost are described. Important terms are defined.
Giving many examples, the contribution shows how pump operators may influence the life, efficiency and overall cost of their pumps. Further, it is shown that both the detection of unfavourable or non-optimal operating conditions and the identification of causes necessitate extensive knowledge and experience. (orig.)
This book includes the latest developments and covers pump performance, selection and operations, materials, seals and packings, effective fluid characteristics, filtration, piping systems, economics, valves, instrumentation, automatic controls, power transmission equipment, pump and pipeline heating, and more. An extensive data section contains formulas, charts, symbols, nomographs, and standard specification documents.
Pumping is one of the means for storing vast quantities of energy. This article analyses its principles and ways of implementation with emphasis on its double aspect, e.g., on the one hand, off-peak power is transferred to the periods of heaviest load and is thus valorized, even when taking into account losses due to poor efficiency of operations in the pumping and turbine modes, and on the other hand, plants have great flexibility in operation, faciliting the permanent fitting of generation to demand.
Experience and technical innovations in power plant engineering have resulted in continuous improvements of operation control, availability and safety of pumped storage plants. Process control is constantly improved as new developments are made in equipment and systems engineering. Plant control concepts with increasingly complex automation hierarchy are described by which pumped storage processes can be controlled optimally, reliably, and automatically.
A new external-PIXE system utilizing a differential pumping technique, which can completely protect the accelerator and vacuum pumps when the exit foil breaks down, has been developed. Applications to analyses of liquid and heavily-outgassing samples were successfully achieved. Also, experiments for evaluating the efficiency of the system were performed and results will be presented. (author)
The data on the multilayer operation of the objects, located in the climatic conditions of the central area of Russia and equipped with the geothermal heat-pumping systems of the heat supply are presented. The results of the analytical studies on evaluating the geothermal heat-pumping systems of the heat supply integration efficiency into the structure of the energy supply system, prevailing in the country, are presented
Ground water ranging in temperature from only 38/sup 0/ to 140/sup 0/F can supply a considerable amount of heat energy when couple with a geothermal or ground-water heat pump. The heat pump's method of operation is examined as well as its performance characteristics. (MHR)
The development of a gas-operated diffusion absorption heat pump for the heating of living spaces is described. By various improvement an energy efficiency of the prototypes of 1.5 was achieved. Structural alterations led to a lower overall height and lower production costs. The CFCs used in electric heat pumps were replaced by environmentally neutral ammonia. Compared with conventional gas heating systems, the CO2 output could be reduced by more than 30%. figs., tabs.
A cryocondensation pump was designed for the baffle chamber of General Atomics DIII-D tokamak and will be installed in the fall of 1992. The purpose of the pump is to study plasma density control by pumping the divertor. The pump is toroidally continuous, approximately 10 m long and located in the lower outer corner of the vacuum chamber of the machine. It consists of a 1 m{sup 2} liquid helium-cooled surface surrounded by a liquid nitrogen-cooled shield to limit the heat load on the helium-cooled surface. The liquid nitrogen-cooled surface is surrounded by a radiation/particle shield to prevent energetic particles from impacting and releasing condensed water molecules. A thermal enhancement coating was applied to the nitrogen shell to lower the maximum temperature of the shell. The coating is non-continuous to keep the toroidal electrical resistance high. The whole pump is ...
In this article, we investigate the "naive non-abelianization" (NNA) contributions of the higher-twist Feynman diagrams to the large-$p_T$ inclusive pion production cross section in proton-proton collisions and present the general formulae for the higher-twist differential cross sections in the case of the running coupling and frozen coupling approaches. We compared the resummed "naive non-abelianization" higher-twist cross sections with the ones obtained in the framework of the frozen coupling approach and leading-twist cross section. The structure of infrared renormalon singularities of the higher twist subprocess cross section and it's resummed expression (the Borel sum) are found. It is shown that the resummed result depends on the choice of the meson wave functions used in the calculations. We discuss the phenomenological consequences of possible higher-twist contributions to the meson production in proton-proton collisions in within NNA ...
This sampling and analysis plan (SAP) identifies characterization objectives pertaining to sample collection, laboratory analytical evaluation, and reporting requirements for vapor samples obtained during the operation of mixer pumps in tank 241-AZ-101. The primary purpose of the mixer pump test (MPT) is to demonstrate that the two 300 horsepower mixer pumps installed in tank 241-AZ-101 can mobilize the settled sludge so that it can be retrieved for treatment and vitrification. Sampling will be performed in accordance with Tank 241-AZ-101 Mixer Pump Test Data Quality Objective (Banning 1999) and Data Quality Objectives for Regulatory Requirements for Hazardous and Radioactive Air Emissions Sampling and Analysis (Mulkey 1999). The sampling will verify if current air emission estimates used in the permit application are correct and provide information for future air permit applications.
The world of antibiotic drug discovery and development is driven by the necessity to overcome antibiotic resistance in common Gram-positive and Gram-negative pathogens. However, the lack of Gram-negative activity among both recently approved antibiotics and compounds in the developmental pipeline is a general trend despite the fact that the plethora of covered drug targets are well-conserved across the bacterial kingdom. Such intrinsic resistance in Gram-negative bacteria is largely attributed to the activity of multidrug resistance (MDR) efflux pumps. Moreover, these pumps also play a significant role in acquired clinical resistance. Together, these considerations make efflux pumps attractive targets for inhibition in that the resultant efflux pump inhibitor (EPI)/antibiotic combination d...
Tata Electric Companies (TEC) are engaged in the generation of hydro and thermal energy. TEC, to minimise backing down of its thermal units in off peak hours and also to at least partially meet the growing deficit in the supply during peak hours is moving to install pumped storage plants (PSPs) utilising off-peak surplus energy for pumping the water from lower pond to the upper pond for subsequent utilisation for power generation during peak hours. In view of some of the infra structural facilities such as storage ponds, water conductor system, transmission lines, etc. being already available, at the existing hydro power stations owned by TEC, the pumped storage units are being proposed within the environs of existing hydro stations, i.e. a 150 MW pumped storage unit at Bhira and a 90 MW pumped storage unit at Bhivpuri. The projects are described and cost estimates is given. ...
An attempt to develop a simple framework for financial evaluation of renewable energy technologies (RETs) such as photovoltaic (PV) pump, windmill pump, biogas and producer gas-driven dual fuel engine pumps for irrigation water pumping has been made. The unit cost of water and unit cost of useful energy delivered by the RETs have been estimated. The monetary benefits that accrued to the end-user have been quantified in terms of the amount of diesel or electricity saved. Financial figures of merit for the investments made in the RETs have been estimated. The effect of fuel price escalation on these measures of financial performance has also been evaluated along with the estimation of the break-even prices of fuels likely to be substituted by RETs. Results of some exemplifying calculations are presented and briefly discussed.
Abstract The purpose of this study was to compare the HL 20 roller pump (Jostra USA, Austin, TX, USA) and Rotaflow centrifugal pump (Jostra USA) on hemodynamic energy production and gaseous microemboli (GME) delivery in a simulated neonatal cardiopulmonary bypass (CPB) circuit under nonpulsatile perfusion. This study employed a simulated model of the pediatric CPB including a Jostra HL 20 heart lung machine (or a Rotaflow centrifugal pump), a Capiox BabyRX05 oxygenator (Terumo Corporation, Tokyo, Japan), a Capiox pediatric arterial filter (Terumo Corporation), and inch tubing. The total volume of the experimental system was 700 mL (500 mL for the circuit and 200 mL for the pseudo neonatal patient). The hematocrit was maintained at 30% using human blood. At the beginning of each trial, a 5 ...
This paper presents a new application in dynamic voltage control based on an older method of voltage regulation. The resulting method is suitable for adoption inn multi-unit pumped storage plants. Inherent operation characteristics of pumped storage plants in the pumping mode can created visible load rejection overvoltages on the transmission and the nearby distribution networks and cause customer complaints. This paper proposes a method in which the on-line units' excitation system impedance compensators are utilized to reduce the magnitude of these overvoltages. This paper presents the theoretical background, computer simulation results, and the field test results at the Pacific Gas and Electric Company's Helms Pumped Storage Plant. This paper should be of interest in the areas of power system planning as well as power system operation.
In this study, a new type of thin, compact, and light weighed diaphragm micro-pump has been successfully developed to actuate liquid by the vibration of a diaphragm. The micro-diaphragm pump with two valves is fabricated in an aluminum case by using highly accurate CNC machine, and the cross-section dimension is 28?mm??5?mm. Both valves and diaphragm are manufactured from PDMS. The amplitude of vibration by a piezoelectric device produces an oscillating flow and alters the chamber volume by the curvature change of a diaphragm. Several experimental set-ups for performance tests in a single micro-diaphragm pump, isothermal flow open system, and a closed liquid cooling system are designed and implemented. The performance of a one-side actuating micro-diaphragm pump is affected by the design ...
The operation of pumped-storage plants (PSP) is based on the daily load variations of power demand. It performs power generation at peak load times during the day, and pumps water up into the reservoir during the off-peak times at night. In the Taipower system in Taiwan, there are two pumped storage plants with ten units. These had a total installed capacity of 2,602 MW or a 12 percent capacity at the end of 1995. The plants were able to reduce system generation costs and improve reliability. A Pumped-Storage Plant Benefit Analysis (PSPBA) program was established using the principle of economic dispatch in 1985. This paper explains the rules of the program, the analysis results of the past 10 years, and a a cost benefit evaluation. It was found that the advantages of PSP are not only in supplying the power for peak load, but also in decreasing the total fuel cost. 5 figs., 4 refs.
Fluidic two diode pumps have been developed for moving highly toxic and for radioactive waste liquors about chemical plant. The pumps have a cylinder into which liquor is initially sucked and then expelled. For situations where no maintenance can be carried out the need has arisen for a fluidic alternator to the solenoid ejector system used on top of the pump cylinder to supply an alternating negative/positive air supply. A fluidic air alternator has been constructed by modifying a small vortex amplifier and inserting an ejector opposite to the throat of the outlet diffuser. The vortex valve ejector is described and performance characteristics are presented. Several developments of the V.V.E. for fluidic pumping and other applications are also reported. (author).
Nonevaporable getters (NEGs) have been extensively studied in the last several years for their sorption properties toward many gases. In particular, an innovative alloy as a thin film by magnetron sputtering was developed and characterized at the European Organization for Nuclear Research. It is composed of Ti-Zr-V and protected by an overlayer of palladium (Pd), according to a technology for which the authors got the licence. NEG-Pd thin films used in combination with ion getter pumps is a simple, easy way to handle pumping devices for ultrahigh and extremely high vacuum applications. To show how to apply this coating technology to the internal surface of different types of ion pumps, the authors carried out several tests on pumps of various shapes, sizes (in terms of nominal pumping speed), and types (diode, noble diode, and triode). Special care was taken during the thermal cycle ...
Versatility of the TRNSYS software program, the ease with which new components can be incorporated into the software, and its application to simulate heat pump systems was discussed. A case history was described in which the package, augmented by the addition of several recent large-scale heat pump projects, was used in calibrating a residential geothermal heat pump system at a military housing project in Fort Polk, LA. The project involved retrofitting over 4000 air source heat pumps with geothermal heat pumps in an energy savings performance contract. The calibration of the component models led to a system model which accurately predicts the performance of the geothermal heat pump. The lessons learned from the calibration exercise were used to help to predict the energy savings from one of the electric feeders at the base which serves some 200 of the 4000+ ...
Under the new name of ``geothermal heat pump``, ground-source heat pumps are currently high in demand in Northern America. In sectors characterized by heating and cold air demand, their advantages can be exploited to the full. For Germany, the end-use-energy substitution potential of geothermal heat pumps has been estimated at 1310-1470 PJ annually. Whether this potential can actually be exploited depends essentially on the development of energy prices, but also on the resourcefulness of plant and heat pump manufacturers in upgrading and cheapening geothermal heat pumps. (orig./RHM) [Deutsch] Unter der neuen Bezeichnung `Geothermal Heat Pump` erlebt die erdgekoppelte Waermepumpe z.Zt. in Nordamerika einen Verbreitungsschub. In dem durch Heiz- und Kuehlbedarf charakterisierten Umfeld kann sie Ihre Vorteile voll nutzen. Fuer Deutschland kommt eine Schaetzung zu ...
Spin-lattice relaxation rates of protein and water protons in dry and hydrated immobilized bovine serum albumin were measured in the range of 1H Larmor frequency from 10 kHz to 30...Full Text Available
Calculations of dose per monitor unit (D∕MU) are required in addition to measurements to increase patient safety in the clinical practice of proton radiotherapy. As in conventional photon and...Full Text Available
Proton and neutron transfer populating low-lying states have been studied in the system {sup 144}Sm+{sup 88}Sr at an energy below the Coulomb barrier. The experimental cross sections for the single proton transfer are well reproduced by DWBA-calculations using spectroscopic information from light ion reactions. The two-proton transfer appears enhanced relative to the uncorrelated sequential transfer of single protons. The same holds for the transfer of proton pairs, the enhancement is kept for the second pair. This is interpreted as a supercurrent between two superfluid nuclear proton-pair wave functions: More mass and charge is transported per time unit in pairs than by single nucleons. Neutron transfer is observed with large cross sections and is found to contribute to the energy loss observed in the transfer reactions. For mixed ...
Proton and neutron transfer populating low-lying states have been studied in the system "1"4"4Sm+"8"8Sr at an energy below the Coulomb barrier. The experimental cross sections for the single proton transfer are well reproduced by DWBA-calculations using spectroscopic information from light ion reactions. The two-proton transfer appears enhanced relative to the uncorrelated sequential transfer of single protons. The same holds for the transfer of proton pairs, the enhancement is kept for the second pair. This is interpreted as a supercurrent between two superfluid nuclear proton-pair wave functions: More mass and charge is transported per time unit in pairs than by single nucleons. Neutron transfer is observed with large cross sections and is found to contribute to the energy loss observed in the transfer reactions. For mixed proton-neutron ...
The measured result of charged multiplicity in cosmic-ray proton induced nuclear reaction from Chinese satellite emulsion is reported. The correlation of shower and heavy particles is discussed and compared with p-emulsion interactions.
The data are analyzed on cumulative antiproton production on Be, Al, Cu, and Ta nuclei induced by 10 GeV protons. The analysis is carried out in the framework of the flucton quark fragmentation model.
Depending on their unique physical properties, proton and heavy ions have taken an irreplaceable role in modern means of tumor treatment. One-step process and two-step process physical models were employed to explain the mechanism of ion energy loss. The transport process of proton and "1"2C in water was simulated by Geant4 toolkit to study the physical properties of ion beam. The calculation results were discussed, which showed the advantages and disadvantages of proton and "1"2C in the medical application. (authors)
Proton production in pA interactions in the kinematically forbidden region is studied using the intranuclear cascade model for the primary proton energies 7.5 and 8.9 GeV/c. The region of secondary-proton kinetic energies above 100 MeV, where the contribution from the post-cascade stages of the interaction is small, is studied. The calculated energy and angular spectra are in good agreement with the experimental ones. The mechanisms of multiple rescattering of particles on the nucleons of the nucleus and ..pi..-meson absorption on a two-nucleon flucton are analyzed. The kinematical ranges where these mechanisms operate are determined.
At the conclusion of polarized proton commissioning in February 1986, protons with an average polarization of 45%, momentum of 21.7 GeV/c, and intensity of 2 x 10/sup 10/ protons per pulse, were extracted to an external polarimeter at the Brookhaven AGS. In order to maintain this polarization, five intrinsic and nearly forty imperfection depolarizing resonances had to be corrected. An apparent interaction between imperfection and intrinsic resonances occurring at very nearly the same energy was observed and the correction of imperfection resonances using ''beat'' magnetic harmonics discovered in the previous AGS commissioning run was further confirmed.
Techniques for studying nuclear structure are reviewed. Examples are given of charge density determinations by electron and proton inelastic scattering. (AIP)
No magnetic monopoles were found in 2.5*10/sup 18/ primary proton- aluminium interactions produced by exposing an aluminium target to the Fermilab 300 GeV/c proton beam. Negative searches have also resulted from exposures of material to electrons at SLAC and from pp interactions at the CERN-ISR. The monopole pair production probability in proton-nucleon collisions is shown to be of order 10/sup -18/ or less, with 95% confidence level, if monopoles have masses less than 12 GeV. (24 refs).
In Korea, the Proton Engineering Frontier Project (PEFP) is building a proton linear accelerator facility with energy up to 100MeV and a beam current of 20mA. In this study, a radiation field after shutdown in the accelerator facility of the PEFP was evaluated for the purpose of the radiation shielding by using MCNPX code. A facility modeling was performed for the accelerator tunnel building, accelerator chain, target rooms and beam experiment hall. And radiation source terms were evaluated in the facility. With this facility, model and radiation source terms, the concentration of 41Ar was evaluated and the cooling time satisfying regulation in Korea was calculated.
The emission of light charged particles from heavy fragments of uranium fission induced by 153-MeV protons is studied. The probability of their emission is 2.7 x 10{sup - 2} per fission event. It is found that these particles affect the distribution of angles of fragment divergence and the angular distribution of heavy fragments with respect to the primary-proton beam. Experimental results suggest that the preequilibrium emission of particles is correlated with fission. Two mechanisms of interaction between 153-MeV protons and uranium nuclei are considered. 13 refs., 10 figs., 1 tab.
This book explores the development, present, and future applications of proton microprobes in the micrometer range. Among the topics discussed: the use of proton beams for analytical purposes; techniques of focusing or collimating ion beams; improving and measuring beam spots; the analytical capabilities of the nuclear microprobe in comparison to other micro techniques; and applications and results by several internationally known microprobe laboratories.
The NuMI beam at Fermilab has delivered over 5 x 10{sup 20} 120 GeV protons to the neutrino production target since the start for MINOS [1] neutrino oscillation experiment operation in 2005. We report on proton beam commissioning and operation status, including successes and challenges with this beam.
An internuclear cascade-evaporation code is used to model energy deposition in thin slabs of silicon. This model shows that protons produce a significant number of events with effective Linear Energy Transfer (LET) greater than 8 MeV cm"2/mg and demonstrates that proton testing of microelectronic components can be an effective way to screen devices for low earth orbit susceptibility to heavy ions.
Radiation therapy has shown definite technical improvement due to application of proton beam irradiation. Clinical results of proton beam therapy also suggested enlargement of indication ranges in radial treatment and decrease of post radiation damages of the treatment of cancers in deep-seated organs. Inprovement of result in cancer therapy could be expected by this treatment technique in the future.
Production of lead-203 by proton irradiation of bismuth metal has been investigated as a replacement method for commercially available lead-203. Targets of bismuth metal (0.1 cm thick) were irradiated for periods of 1-3 hours with 90 MeV protons. After processing of the target, the estimated yield of lead-2-3 was 30 millicuries/microamp.
Isospin-breaking effects in the baryonic sector are studied in the framework of a medium-modified Skyrme model. The neutron-proton mass difference in infinite, asymmetric nuclear matter is discussed. In order to describe the influence of the nuclear environment on the skyrmions, we include energy-dependent charged and neutral pion optical potentials in the s- and p-wave channels. The present approach predicts that the neutron-proton mass difference is mainly dictated by its strong part and that it strongly decreases in neutron matter. (orig.)
Depth dose distributions for protons in the energy range from 2 to 600 MeV have been calculated by Monte Carlo and analytical methods. The dependence on energy of Maximum Dose Equivalent (MDE), quality factor and isotropic factor recommended for practical use are presented. The problems connected with regulation of maximum permissible proton fluxes are discussed. (author).
A large set of data on proton-proton differential cross sections, analyzing powers and the double-polarization parameter A{sub NN} is analyzed employing the Regge formalism. We find that the data available at proton beam momenta from 3GeV/c to 50GeV/c exhibit features that are very well in line with the general characteristics of Regge phenomenology and can be described with a model that includes the {rho}, {omega}, f{sub 2}, and a{sub 2} trajectories and single-Pomeron exchange. Additional data, specifically for spin-dependent observables at forward angles, would be very helpful for testing and refining our Regge model. (orig.)
TiH{sub 2} and TiD{sub 2} thick targets were bombarded with 100 to 200 keV protons. Evidence for nuclear reactions was obtained by means of a surface barrier particle detector. Proton irradiation of TiD{sub 2} produced the following observations: {alpha} particle emission identified as (p, {alpha}) reactions from {sup 11}B and {sup 7}Li impurities in the target at ppm concentrations; and {approx}3 MeV proton and {approx}1 MeV triton emission from secondary D-D reactions caused by elastic scattering of the primary proton with a target deuteron. A 3.9 MeV {alpha} particle peak measured by others was not observed. (author)
Lifetime observations on a group of 358 rhesus monkeys indicate that life expectancy loss from exposure to protons in the energy range encountered in the Van Allen belts and solar proton events is influenced primarily by the dose rather than the energy of radiation. After 24 years, life expectancy losses from similar surface doses of low-LET (138-2300 MeV) and high-LET (32-55 MeV) protons are not significantly different, but the high-LET protons are associated with more deaths in the early years, while the low-LET protons contribute more to mortality in later years. In males, the most significant cause of life shortening is nonleukemia cancers.
The determination of ratio of neutron over proton matrix elements by inelastic proton scattering, for 0{sup +}{yields}2{sup +} transitions, is investigated via the comparison between experimental data and theoretical calculations. Calculations into the context of a macroscopic and a microscopic description are performed for a wide mass range nuclei: {sup 18}O, {sup 30}Si, {sup 32,34}S, {sup 48}Ca, {sup 88}Sr, for which these ratios were determined previously with an independent technique. At that point the choice of the theoretical model may be very critical. It is thus the purpose of this investigation to point out the most suitable model. It is found that in general both theoretical models can be employed for the reliable determination of neutron over proton matrix element ratios.
The determination of ratio of neutron over proton matrix elements by inelastic proton scattering, for 0"+#->#2"+ transitions, is investigated via the comparison between experimental data and theoretical calculations. Calculations into the context of a macroscopic and a microscopic description are performed for a wide mass range nuclei: "1"8O, "3"0Si, "3"2","3"4S, "4"8Ca, "8"8Sr, for which these ratios were determined previously with an independent technique. At that point the choice of the theoretical model may be very critical. It is thus the purpose of this investigation to point out the most suitable model. It is found that in general both theoretical models can be employed for the reliable determination of neutron over proton matrix element ratios.
The portion of the potential energy surface (PES) of acetylacetone relevant for the intramolecular proton transfer reaction is studied using ab initio and DFT methods. The best estimate of the barrier governing proton transfer was found to be 3.4 kcal mol{sup -1} at the MP4(FC)/6-311 + G(2d,2p)//MP2(FC)/6-311 + G(2d,2p) level of theory. Six stationary points on the PES were characterized as well as the reaction paths connecting these points. Special attention paid to the pathway of intramolecular proton transfer reveals that the internal rotation of the methyl group adjacent to the carbonyl group and the proton transfer reaction are consecutive processes.
The LAHET code system calculations and experimental results for proton interactions with an energy <50 MeV are compared. For these energies, the theories behind the LAHET models are not applicable. Three quantities compared are (a) the magnitude of the neutron yield generated through proton interactions, (b) the energy and angular distributions of the resultant neutrons, and (c) the residual nuclei produced by proton interactions (spallation products). The comparisons are for protons incident on iron and copper, except in the case of the energy and angular distributions, which are calculated only for iron. The neutron yields predicted by LAHET agree with published measurements to within 50% for both materials. For iron, the predicted energy and angular distributions agree to within a factor of 3. Finally, the predicted spallation product yields of both materials agree with measurements to within a ...
For charged particle irradiations, the response of an imaging plate (IP) changes around the Bragg peak. Therefore, an appropriate compensation is necessary for the evaluation of dose distribution formed by charged particles such as protons. In this paper, the response of IPs to clinical proton beams is investigated. An experimentally-obtained depth-dose distribution (an ordinary Bragg curve) by a silicon semiconductor detector (SSD) is employed to evaluate the compensation factors as a function of proton penetrating depth, i.e. residual range. A typical dose distribution in a water phantom formed by an L-shaped bolus is measured by IPs and corrected by using the information of those compensation factors; the residual proton range is successfully calculated by the pencil beam algorithm at an arbitrary point. The results show a good agreement with the measurements by the SSD within the rms error of 3.0%.
The proton beam has a unique advantage over the electron and photon beams in that it can give very high radiation dose to the tumor volume, while effectively sparing the neighboring healthy tissue and organs. For the clinical application of the proton beam, it is very important to confirm the location of the proton beam in the patient, preferentially during the treatment. It has been suggested that the range of the proton beam in the patient can be determined by measuring prompt gammas from the proton beam passage. Recently, a prototype prompt-gamma scanning system has been constructed and tested using experimental and therapeutic proton beams. The measurement results for the proton beams of 70 . 230 MeV showed that a clear correlation exists between the distribution of the prompt gammas and the proton beam range. The ...
An attempt to determine lysozyme hydration by employing a proton nuclear magnetic resonance (NMR) spin-echo technique and to correlated such measurements with the 20 "0C sorption equilibrium data is made. Determinations of specific site hydration for lysozyme, as well as proton NMR transverse relaxation rates for five different types of water populations in the lysozyme-water system, are presented over the whole range of lysozyme concentrations. The proton spin-echo NMR results are consistent with a three-component analysis of the sorption isotherm up to 70% water content, above which two additional water populations are identified by 360-MHz proton NMR spin-echoes. On the basis of the proton NMR results, a major component (III) of the lysozyme sorption isotherm is assigned to the water trapped between lysozyem molecules, whose relaxation rate is increased by diffusion barriers. The ...
The hydromechanical effect of hydroelectric stations on zooplankton is customarily regarded as a constantly acting and comparatively harmless factor, since its destruction is inevitable when water masses are passed through hydroelectric stations, but its capacity for restoration is high (i.e., destruction of the zooplankton of the forebay is compensated by its production in the after bay). It is not known how correct such an opinion is, or what is the true balance of losses and reproduction of zooplankton in the forebays and after bays of hydroelectric stations. However, hydroelectric plants of a new type, pumped-storage plants, have been constructed in recent years and others are planned for the Dnieper reservoirs. The operational principle and purpose of these plants is that they employ special vertical turbine-electric pumps that pump water at night from the reservoirs into pumped-storage facilities ...
The paper is concerned with the economic operation of power systems comprising pumped storage and thermal plants. In power systems, pumped storage plants may receive the energy required for pumping water either from the system in which they are integrated or from a neighbouring system. Therefore, two mathematical formulations of the problem are presented depending on the source of energy during pumping. In both cases, the problem is reduced to a non linear optimization problem. Two numerical techniques are suggested for the solution of this optimization problem, namely the Lagrangian Multipliers technique and the Rosen Gradient Projection technique. Numerical examples are presented to demonstrate the techniques. Although the Lagrangian Multipliers technique has the advantage of being a well known technique, however, computer wise, the Rosen Gradient Projection technique proves to be more efficient. The ...
A centrifugal pump was developed for the efficient and reliable transfer of liquid helium in space. The pump can be used to refill cryostats on orbiting satellites which use liquid helium for refrigeration at extremely low temperatures. The pump meets the head and flow requirements of on-orbit helium transfer: a flow rate of 800 L/hr at a head of 128 J/kg. The overall pump efficiency at the design point is 0.45. The design head and flow requirements are met with zero net positive suction head, which is the condition in an orbiting helium supply Dewar. The mass transfer efficiency calculated for a space transfer operation is 0.99. Steel ball bearings are used with gas fiber-reinforced teflon retainers to provide solid lubrication. These bearings have demonstrated the longest life in liquid helium endurance tests under simulated pumping conditions. Technology developed in the project ...
Ground-source heat pump systems (GSHPSs), also referred to as geothermal heat pump systems (GHPSs), have been widely used in residential and commercial buildings for years due to their outstanding energy utilization efficiencies. In this study, an energy and exergy modeling of solar assisted ground-source heat pump systems for residential applications is presented for system analysis and performance evaluation. In this regard, the performance of a solar assisted ground-source heat pump heating system, installed in Solar Energy Institute of Ege University, Izmir, Turkey, is evaluated based on the actual operational data to show how energy and exergy efficiencies values change with the system. The average heating coefficient of performances (as energy efficiencies) of the solar assisted ground-source heat pump (GSHP) unit and the overall system are obtained to be 2.64 and 2.38, ...
One of the principal problems confronting the remediation of Bear Creek Valley is the cleanup of contaminated groundwater. The S-3 Site is one of the locations in the valley where groundwater is most contaminated, and contamination from the S-3 Site has also caused extensive contamination of downgradient groundwater. This groundwater plume, therefore, has a high priority in the Bear Creek Valley remedial process. Pumping and treating groundwater was identified early in the feasibility study as a likely remedial alternative for the S-3 Site groundwater plume. The hydrology and geochemistry of the plume are extremely complex. There is a high degree of uncertainty in the current understanding of how the aquifer will react physically and chemically to pumping, making evaluation of a pump-and-treat alternative impractical at the present time. Before a pump-and-treat alternative can be evaluated, its ...
Using standard microfabrication techniques, it is now possible to construct devices that appear to reliably manipulate electrons one at a time. These devices have potential use as building blocks in quantum computing devices, or as a standard of electrical current derived only from a frequency and the fundamental charge. To date, the error rate in semiconductor 'tuneable-barrier' pump devices, those which show most promise for high-frequency operation, have not been tested in detail. We present high-accuracy measurements of the current from an etched GaAs quantum dot pump, operated at zero source-drain bias voltage with a single ac-modulated gate at 340 MHz driving the pump cycle. By comparison with a reference current derived from primary standards, we show that the electron transfer accuracy is better than 15 parts per million. High-resolution studies of the dependence of the pump current on the ...
This paper presents a novel organization of switch capacitor charge pump circuits based on voltage doubler structures. Each voltage doubler takes a DC input and outputs a doubled DC voltage. By cascading voltage doublers the output voltage increases up to 2 times. A two-phase voltage doubler and a multiphase voltage doubler structures are discussed and design considerations are presented. A simulator working in the Q-V realm was used for simplified circuit level simulation. In order to evaluate the power delivered by a charge pump, a resistive load is attached to the output of the charge pump and an equivalent capacitance is evaluated. To avoid the short circuit during switching, a clock pair generator is used to achieve multi-phase non-overlapping clock pairs. This paper also identifies optimum loading conditions for different configurations of the charge pumps. The proposed ...
Recent research work on adjustable speed pumped storage plants conducted in Japan, the USA and Europe suggests that they have many advantages over fixed-speed plants, and can contribute to power system regulation even in pump mode. This paper describes two types of static frequency converter for such pumped storage plants, especially those with greatly fluctuating heads. The design characteristics and operation of the doubly fed induction machine and the synchronous machine with DC link converter are set out and the devices compared. (UK)
The major details of the inspection and replacement of the bearing journals on each of the four heat transport pumps (HTPs) at Wolsung nuclear generating station in Korea are presented in this paper. Investigation following fracture of one of the journals in 1985 revealed that it was excessively hard. The journal material (ASTM A296 CA 40) is considered to be prone to stress corrosion fatigue if the hardness exceeds Rc 40. In 1986 May, during a planned outage, the HTPs were disassembled, the journals were inspected, found to be excessively hard, and all were replaced. At the same time, the pump to motor couplings were all refurbished to ensure proper alignment.
Pumped storage plants (PSP) enable the storage of energy with rated capacities of order of GW at a single site. Reservoirs allow charging and discharging times of at least hours, sometimes days or even up to several weeks. Short ramp-up times permit the participation in the secondary reserve market as a standing reserve. For bulk energy storage, PSP reach the lowest, specific costs. In the EU27 countries, Norway and Switzerland, a total of 44 GW of pumped storage capacity is installed. The utilisation of PSP strongly correlates with the amount of conventional generation capacity, rather than with topographical options. (orig.)
Originally designed exclusively for peak load covering, pumped storage plants are now faced with new challenges brought about by the deregulation of the electricity market and the substantial growth of wind power capacity. Today's pumped storage plants are started more frequently and often for shorter periods of time. The grid controlling tasks have increased the importance of the role played by this type of power plant and improved sales considerably. But the operational demands have grown substantially as well. This paper discusses the ensuing adaptation of power plant operation as well as options available to power plant operators. (orig.)
The production of polarized negative ion beams by collisional pumping is described. Collisional pumping utilizes repeated charge changing collisions in a thick electron-spin-polarized gas or vapor target to form a polarized fast atom beam. The polarized fast atom beam is then partially converted into a polarized negative ion beam in a vapor target. Analysis is presented for a hydrogen beam passing through either a thick polarized H atom target or a thick polarized alkali target. Large polarizations and large currents may be possible.
The production of polarized negative ion beams by ''collisional pumping'' is described. Collisional pumping utilizes repeated charge changing collisions in a thick electron-spin-polarized gas or vapor target to form a polarized fast atom beam. The polarized fast atom beam is then partially converted into a polarized negative ion beam in a vapor target. Analysis is presented for a hydrogen beam passing through either a thick polarized H atom target or a thick polarized alkali target. Large polarizations and large currents may be possible.
The lateral natural frequency and vibration response analyses of the Large Scale Breeder Reactor (LSBR) primary pump were performed as part of the total dynamic analysis effort to obtain the fabrication release. The special features of pump modeling are outlined in this paper. The analysis clearly demonstrates the method of increasing the system natural frequency by reducing the generalized mass without significantly changing the generalized stiffness of the structure. Also, a method of computing the maximum relative and absolute steady state responses and associated phase angles at given locations is provided. This type of information is very helpful in generating response versus frequency and phase angle versus frequency plots.
This report documents results of a preliminary hazard analysis (PHA) covering the existing Crane Chempump and the new salt well pumping design. Three hazardous conditions were identified for the Chempump and ten hazardous conditions were identified for the new salt well pump design. This report also presents the results of the control decision/allocation process. A backflow preventer and associated limiting condition for operation were assigned to one hazardous condition with the new design.
Geothermal heat pump systems are a promising new energy technology that has shown rapid increase in usage over the past 10 years in the United States. These systems offer substantial benefits to consumers and utilities in energy (kWh) and demand (kW) savings. The purpose of this study was to determine what existing monitored data were available mainly from electric utilities on heat pump performance, energy savings, and demand reduction for residential, school, and commercial building applications. Information was developed on the status of electric utility marketing programs, barriers to market entry, incentive programs, and benefits.
Geothermal heat pump systems are a promising new energy technology that has shown rapid increase in usage over the past ten years in the United States. These systems offer substantial benefits to customers and utilities in energy (kWh) and demand (kW) savings. The purpose of this study was to determine what existing monitored data was available mainly from electric utilities on heat pump performance, energy savings and demand reduction for residential, school, and commercial building applications. Information was developed on the status of electric utility marketing programs, barriers to market penetration, incentive programs, and benefits.
As an application of ART2 neural networks, computer aided monitoring of pump efficiency is successfully examined for an industrial waste-liquid treatment process with measured data of valve openness and liquid flow rates. By running the neural networks in parallel, we confirm that accuracy to detect system changes is good, and the adjustment of classifier parameters is relatively easy. Investigating the resulting classes carefully, frequency of each class is correlated with pump efficiency. The relative amount of variables are also related to the classes. (author)
The use of reversible pump/turbine sets in pumped storage has created a requirement for rapid reversibility. Softstart technology, based on static frequency converters (SFC) has evolved to such an extent that it is now the best choice for serving this purpose, both from a technical and from an economic point of view. The objective of our paper is to give the owners of pumped storage plants and those persons responsible for the selection, the operation or the maintenance of the electrical equipment the necessary insight into the SFC functions, features and all other application related aspects, to facilitate their decision making process. Case studies are included.
The Michigan Electric Coordination Center (MEPCC), operated by Consumers Power and Detroit Edison Companies, has the responsibility for scheduling the Ludington pumped storage plant. Ludington has an extremely large economic effect on the Consumers Power and Detroit Edison Companies' system due to its size (over 1800 MW net demonstrated generating capability). This paper presents a dynamic programming algorithm for scheduling large pumped storage plants and shows how this method can be coordinated with the commitment of the thermal units of the system.
A descriptive model and design procedure for the DC electromagnetic flow coupler is developed based on a quasi-one-dimensional analysis previously developed for the DC electromagnetic pump. It is shown that for a particular flow coupler geometry, the total efficiency and the pressure gradients through the pump and generator depend on two parameters - the Hartmann number and the ratio of the pump flow rate to generator flow rate. Thus, for a fixed Hartmann number the efficiency depends only on the flow ratio. However, for a fixed pressure rise through the pump it is shown that the efficiency depends only on the Hartmann number. Nomographs showing the operating characteristics and critical design points are presented. Example calculations for a full-size unit, suitable for use in a liquid-metal cooled fast breeder reactor, are also discussed using the design nomographs.
Ground thermal energy storage is a means of storing thermal energy underground during the summer and utilizing it during the winter. The main use of such a technology is in the heating, ventilating and air conditioning sector where the ground provides a stable temperature reservoir for a heat pump system. Heat pumps are mechanical systems that provide heating to a space in the winter, and cooling in the summer. They are increasingly popular because the same system provides both heating modes, depending on the direction of the cycle upon which they operate. The stable temperature reservoir allows the heat pump system to run at a higher efficiency. Thermal energy is transmitted to and from the ground by circulation of water through standing column geothermal wells. In commercial applications...
This comprehensive final report for the Swiss Federal Office of Energy (SFOE) presents the results of research done in the third phase of a research project that investigated components for small heat pump systems that use ammonia as a working fluid. The report includes a summary of the findings of the first two phases of the project and goes on to describe tests done with rotary vane and scroll compressors. The aims of the project are discussed and the work done is listed chronologically. The construction and the components of the test installation are described in detail. Also, the heat pump testing facilities at the University of Applied Science in Rapperswil, Switzerland, are described. The results of the measurements made for various temperature gradients are presented in detail and commented on; also, the various types of compressor tested and other heat pump compressors are compared.
Within the cardiac cell, the movements of calcium ions are tightly regulated by a number of regulatory proteins including pumps, and channels. The sarcoplasmic reticulum (SR) is in large part...Full Text Available
This report presents the results of a study on Operation and Maintenance (O M) practices in hydroelectric pumped storage plants. The objective of this project, which was sponsored by EPRI, is to record the practical knowledge on the O M of a number of the domestic and foreign pumped storage plants which has been accumulated by their operating staff. Civil, geotechnical, mechanical and electrical aspects of O M of the thirty-five plants visited are discussed, and some general conclusions, as warranted by the commonality of the problems, are drawn. These conclusions may be useful to the planners and designers of future pumped storage projects. In general, due to their layout, diversity and different modes of operation, the plants have few common problems which, in most cases, are limited to the mechanical and electrical aspects of the plants' operation. The data on plants' specifications, operation and ...
Modern tubular type pumps commonly have lubricated radial bearings which require no compressed water supply and reduce the servicing requirements. Problems that may possibly result from entrained sand in the pumped fluid were solved with the development of ceramic Residur {sup trademark} bearngs in the early eighties. (orig.) [German] In zunehmendem Masse werden Rohrgehaeusepumpen mit foerdermediumgeschmierten Radiallagern ausgestattet, da dies z.B. neben dem Wegfall einer ansonsten notwendigen Druckwasserversorgung auch einen deutlichen reduzierten Wartungsaufwand nach sich zieht. Den Problemen durch eine moegliche Sandbeladung des Foerdermedium wurde bereits durch die Entwicklung der keramischen Residur {sup trademark} -Lager Anfang der 80er Jahre Rechnung getragen. (orig.)
This research report for the Swiss Federal Office of Energy (SFOE) presents the results of a project that examined the feasibility of setting up 'MINERGIE' low-energy-consumption module standards for the production of heat in small residential buildings. The aims of the standards and the basic idea behind the MINERGIE-modules are discussed. The concepts of the modules for heat pumps and wood-fired heating systems and their combination with solar installations are examined, as are their areas of application. The requirements placed on the modules are listed. System concepts, including simple schematics for typical installations, are presented for wood-log, wood-chippings and pellets-fired systems as well as for ground-loop and air-water heat pump systems as well as their solar-aided counterparts. The results of cost-benefit analyses are presented and questions regarding system guarantee and liability are examined.
Congestive heart failure (CHF) is a leading cause of morbidity and mortality. CHF is marked by atrial and ventricular enlargement and reduced cardiac contractility, as well as an association...Full Text Available
Purpose: To eliminate the water level deviation due to the recycling flowrate, as well as enable a stable control to a reference value even upon changes in the recycling flowrate caused by the variation in the opening degree of a minimum flow valve. Constitution: Reactor recycling system comprises a feedwater pump, a flowrate control valve, a reactor water level detector, and a minimum flow line and a minimum flow valve for preventing the overheating of the feedwater pump at a low flowrate. A flowrate compensator is further disposed, in which a recycling flowrate signal is subtracted from a pump flow rate signal and the result is fedback as a compensated pump flowrate signal. This enables the control system to operate at a rapid response for suppressing the effect of the recycling flowrate as external disturbance, whereby the water level in the reactor can be controlled stably to the reference level and ...
This paper presents a new method of extracting biologic particles from a mixture of particles. The method is based on the pumping effect in a p-shaped ultrasonic actuator, which has a gap between its two vibrating metal plates. An adhesive tape is placed at a proper position in the gap. Due to the pumping effect which is induced by the sound field in the gap, the particles with smaller mass and radius in the mixture can be pumped up to reach the adhesive tape; while the ones with larger mass cannot. Therefore, the particles with smaller mass and radius can be extracted from the mixture. A theoretical model which can well explain the operation principle and experimental phenomena is developed. By the experimental results and the theoretical analyses based on the model, the validity of the m...
Many oil-insulated electric power cables are limited by heat buildup caused in part by the low thermal conductivity of the oil. Circulation of the oil is known to reduce the cable temperature, but can lead to excessive pressure buildup on long cables when using conventional pumping methods. An alternate pumping method using distributed electric fields to avoid this pressure buildup is described. Electrohydrodynamic (EHD) pumping was studied both theoretically and experimentally for possible application in underground cable cooling. Theoretical studies included both analytical and finite-element analysis of the flow patterns driven by travelling electric fields. Experimentally, flow rates in a cable-pipe model were measured under a wide variety of operating conditions. Theory and experiment are in agreement for velocities below 10 cm/s, but higher velocities could not be reached in the experiment, due to increased ...
Environmental arsenic is a world-wide health issue, making it imperative for us to understand mechanisms of metalloid uptake and detoxification. The predominant intracellular form is the highly mephitic...Full Text Available
We have developed a liquid jet injector system that can be used for hydrated sample delivery at X-ray Free Electron Laser (XFEL) sources and 3rd generation synchrotron sources. The injector is based on the Gas Dynamic Virtual Nozzle (GDVN), which generates a liquid jet with diameter ranging from 300 nm to 20 {\\mu}m without the clogging problems associated with conventional Rayleigh jets. An improved nozzle design is presented here. A differential pumping system protects the vacuum chamber and an in-vacuum microscope allows observation of the liquid jet for diagnostics while it is being exposed to the X-ray beam. A fiber optically coupled pump laser illuminating the jet is incorporated for pump-probe experiments. First results with this injector system have been obtained at the LCLS.
An exergoeconomic model of a vertical ground-source heat pump residential heating system presented in this study uses exergy and cost energy mass (EXCEM) methods. The data obtained from a ground-source heat pump (GSHP) residential heating system installed at the Solar Energy Institute, Ege University, Turkey, are utilized for calculations at different reference temperature values in the range 0-25{sup o}C. The performance of the geothermal heat pump residential heating system is evaluated to indicate how exergoeconomic parameter values change with system. We also undertake a parametric study to investigate how varying reference temperatures will affect the exergoeconomic analysis of the GSHP system. A correlation between the ratio of thermodynamic loss rate to capital cost and reference state temperature is developed. (author)
The fundamental differences in the type of products sold in both Japan and the US, and some of the reasons for these differences, are outlined. Japan is the largest single country market for residential heat pumps, while the US represents the largest single country market for residential heating equipment. Quite different types and associated features of heat pumps are demanded in the USA and Japan. The term `convenience features`, used to describe the physical characteristics of the user interface device, is explained, as well as the fundamental reasons leading to the particular styles of product sold in each country: (1) product strategy and sales channels, (2) design of housing, (3) climatic factors, and (4) energy costs and distribution. It is stressed that there is no big cooling load in Japan. It is rather the comfort issue that drives the market for heat pumps
W and Z bosons are expected to be produced abundantly at the Large Hadron Collider (LHC). This large dataset and the high LHC energy will allow for detailed studies of their properties in a previously unexplored kinematic domain of low parton momentum fraction and high energy scale thus providing, together with the proton-proton nature of the collisions, new constraints on the parton distribution functions and precise tests of perturbative QCD. First determinations of the W -> lnu and Z -> ll (l = e,mu) production cross sections for proton-proton collisions at sqrt(s) = 7 TeV were performed using about 320/nb of data recorded by the ATLAS experiment at the LHC. The results of these measurements for W and Z bosons for proton-proton collisions at sqrt(s) = 7 TeV are presented. In addition ?rst measurements of the ratio between the W and Z/gamma*-cross sections and of the W -> lnu charge asymmetry are also ...
We have performed a detailed analysis of water clustering and percolation in hydrated Nafion configurations generated by classical molecular dynamics simulations. Our results show that at low hydration levels H2O molecules are isolated and a continuous hydrogen-bonded network forms as the hydration level is increased. Our quantitative analysis has established a hydration level (?) between 5 and 6 H2O/SO3- as the percolation threshold of Nafion. We have also examined the effect of such a network on proton transport by studying the structural diffusion of protons using the quantum hopping molecular dynamics method. The mean residence time of the proton on a water molecule decreases by two orders of magnitude when the ? value is increased from 5 to 15. The proton diffusion coefficient in Nafion at a ? value of 15 is about 1.1x10-5 cm2/s in agreement with experiment. The results provide quantitative ...
Activation has been used for many kinds of useful applications, such as use of the radioisotopes for diagnosis and treatment of cancer, and wear (or corrosion) investigation for using thin layer activation (TLA) technique, etc. But activation also has severe problems for the post-processing of the samples; such as time-loss, inconvenience of sample handling, personal radiation safety, etc. For in-vitro experiments, we observed death of tumor cells by proton irradiation. The use of large activated container material can cause erroneous results in this case. To solve these problems, we studied why the samples were activated and how the level of the activation could be reduced. In proton beam irradiation experiments, the target materials could be defined as the container and sample itself. We could easily reduce activation of container material comparing to activation of sample itself. Therefore, we tried to find less activated container material ...
This article describes acoustic methods used in the in-service inspection of the dams and peripheral concrete structures of the Toktogul, Kurpsai, and Bratsk hydroelectric and pumped storage plants. The tests were conducted to assess the compression strength, elasticity, and tensile strength of the concretes. Comparative evaluations against drill core studies proved the acoustic methods to be sufficiently accurate in predicting aging behavior and loss of mechanical and physical integrity in the concretes.
The brochure reports on the construction and method of operation of heat pumps: - Efficiency and temperature difference - output figure - circuit processes - saving of primary energy - monovalent and bivalent plants - absorber, earth collectors - heat recovery. (HW) [Deutsch] Die Broschuere berichtet ueber den Aufbau und die Wirkungsweise von Waermepumpen: - Wirkungsgrad und Temperaturdifferenz - Leistungszahl - Kreisprozesse - Einsparung von Primaerenergie - monovalente und bivalente Anlagen - Absorber, Erdkollektoren - Waermerueckgewinnung. (HW)
Research commenced in FY 97 to determine the suitability of superplasticized cement-sand grouts for backfilling vertical boreholes used with geothermal heat pump (GHP) systems. The overall objectives were to develop, evaluate and demonstrate cementitious grouts that could reduce the required bore length and improve the performance of GHPs. This report summarizes the accomplishments in FY 98.
The paper sets up a simulation of a geothermal heat pump with a non-azeotropic mixture. The model is modified and verified with experimental data. The results of the simulation show that the systematic model can predict the performance within {+-}12% of the experimental data. As a result, some improvements can be provided on the basis of the simulation platform. (Author)
A project to demonstrate residential heating and cooling with a well-water source heat pump is documented. The system is schematically illustrated and described, and project experience is discussed. The system is capable of using source water as cool as 40/sup 0/F. Project expenses are accounted for. (LEW)
Previous models and evaluation techniques based on the Monte Carlo simulation for the reliability assessment of mixed hydrothermal generation systems are extended. Models for reservoirs on multiple rivers and pumped storage plants are developed. Operating and water management policies are extended to include the relative economical effects of operating alternative sources of generation. These effects and the benefits are described and discussed using an extended IEEE reliability test system. (Author).
Pumped storage plants (PSP) supply up to several GW of power and several ten GWh of capacity. Short start-up times and low start-up costs predestine PSP for the control energy market. Grid charges for PSP endanger the further integration of renewable energy and lead to higher electricity supply costs. Therefore, an amendment of legislation is urgently required. Requirements for building large PSP are met at numerous sites in the low mountain ranges of Germany. (orig.)
This paper suggests how nonlinear periodic optimal control of a pumped storage plant can be realized. The control problem consists in maximization of the plant benefits over an operational period. An optimal control law is proposed, yielding a bang-off-bang mode of operation. An algorithm for numerical solution of the problem was developed, and its effectiveness was demonstrated by simulation experiments.
Interchangeable technology from Flexicon Liquid Filling, a business division of Watson-Marlow Pumps Group, has helped family-run diagnostic reagent manufacturer, Hart Biologicals Ltd, to accommodate business growth with the recent upgrade to a tabletop bottle filling and capping machine. A peristaltic dispensing pump is crucial for succes
This report contains the results of a survey of reactor coolant pump shaft seal reliability. The survey sample is representatively large (approx. = 27% of total US commercial plant population) and includes the three industry seal suppliers (Bingham-Williamette, Byron Jackson, and Westinghouse). Operationally incurred/induced problems and seal redesign parameters are identified. Failure hypotheses in the form of fault trees have been developed to describe the failure mechanisms. Recommendations are made for seal reliability improvement.
Heat pumps can be installed indoors or outdoors. H. Klein investigates which site would be preferable for a one-family house. Advantages and disadvantages with regard to necessary space, noise, maintenance and repair are discussed; heat losses in both cases of installations are dealt with. Mathematic calculation shows that indoor installation is safer and more adequate in terms of energy savings.
This workshop on heat pipes and two-phase capillary pumping loops was organized by the French society of thermal engineers. The 11 papers presented during this workshop deal with the study of thermal performances of heat pipes and on their applications in power electronics (cooling of components), and their use in satellites, aircrafts and trains. (J.S.)
The paper describes a way to control methane that is almost self-sufficient. The Methane Buster extracts methane from longwall mines. The machinery can run virtually unattended and is fuelled by a small proportion of the methane that it extracts. The most popular model is the size of a car and weighs 3000 lbs. With pump inlet sizes varying from 6 to 24 ins. The pumps can handle up to 30,000 CFM. 3 photos.
Within the Westeuropean network of the electric current supply a continuing compensation is necessary with respect to the permanent alterations of capacity and frequency. Pumped-storage plants are of considerable significance to meet these requests. The Schluchseewerk AG, Freiburg/Breisgau, has among others five pumped-storage plants in the southern part of the Black Forest. The conception and the operation of them are described. (orig.).
The Sacramento Municipal Utility District is developing a number of demonstration projects using geothermal heat pumps. This paper discusses some of the barriers and issues that have emerged over the past two years. The most important barriers are: regulatory impediments; high first cost; and a lack of local design and installation infrastructure.
Under coaxial flash lamp pumping the laser efficiency of coumarin-4 in slightly basic ethyl alcohol solution as an active medium has reached a value of 0.14%. That is three times higher than that in the basic aqueous solution. Its tunable wavelength range of laser output has extended from 440 to 510 nm with the maximum at 460 nm.
A description is given of an automatic liquid nitrogen pumping system. Pamping of liquid nitrogen iato cooling traps up to a predetermined level is achieved by an automatically controlled compressed air system. An impontant feature of the equipment is the ability to switch automatically from an empty liquid nitrogen reservoir to a full one. This allows for a much more flexible operation than in conventional systems where the reservoir has to be replaced manually when empty. (auth)
A description of LOOP covers the single point mooring (SPM) system; the offshore pipelines connecting each SPM to the pumping platform; the offshore platform complex, a pumping platform and a control platform; the onshore pipelines; and the Clovelly Dome storage terminal.
The "8"6Kr("3He,n)"8"8Sr and "8"8Sr("3He,n)"9"0Zr reactions were studied to determine whether significant excited 0"+ strength was observed or whether these nuclei exhibited absence of excited state strength generally seen away from shell closures. Various properties of the levels are considered including angular distributions, spins, parities, interference, and enhancement. It is concluded that neither "8"8Sr nor "9"0Zr exhibit the strong proton pairing vibration expected for a closed proton shell nucleus.
Decay sequences based on the 1/2"+[660] proton orbital have been identified in "1"7"1Ta and "1"7"7Re based on spin, parity, and large alignment. This decay sequence is observed higher in energy than predicted in cranking calculations based on modified oscillator potentials. Similarly known 1/2"-[541] decay sequences in these and other neighbouring isotopes are observed lower in energy than predicted. A reduction in the strength of the spin-orbit potential for protons is suggested as a solution to these problem. (orig.).
A calorimetric-time-of-flight (CTOF) technique was used for real-time, high-precision measurement of neutron spectrum at the angle of 175 degrees from the initial proton beam direction, which hits a face plane of a cylindrical iron target of 20 cm in diameter and 25 cm thick. A comparison was performed between the neutron spectra predicted by the MARS and the MCNPX code systems and measured by experiments for 0.4-, 0.6-, 0.8-, 1.0-, and 1.2-GeV protons.
A simple highly efficient procedure has been developed for recovery of thallium radioisotopes from lead and bismuth targets irradiated by 1-GeV protons. The procedure is based on the use of extraction chromatography. The cross-sections have been determined for formation of {sup 200}Pb, {sup 201}Pb, {sup 202m}Pb, and {sup 203}Pb radioisotopes in targets from lead with natural isotopic composition, irradiated by 1-GeV protons.
A simple highly efficient procedure has been developed for recovery of thallium radioisotopes from lead and bismuth targets irradiated by 1-GeV protons. The procedure is based on the use of extraction chromatography. The cross-sections have been determined for formation of "2"0"0Pb, "2"0"1Pb, "2"0"2"mPb, and "2"0"3Pb radioisotopes in targets from lead with natural isotopic composition, irradiated by 1-GeV protons.
Special beam extraction channel is used at INR linac for isotope production. It starts from 160 MeV measuring and matching area of accelerator. This choice of beam extraction enables to direct to the target of isotope complex a proton beam of wide energy range up to 160 MeV. It is important for production of different types of nuclides. The measuring results of proton beam behavior in this region are presented. Required beam forming in 160 MeV measuring and matching area of accelerator and in beam extraction channel is discussed.
A mixture of aminoacids was irradiated by a scattered proton beam, its energy varying from 4 to 6.6 MeV, by doses up to 5 x 10"1"1 proton/cm"2 for studying the potentiality of abiogenic synthesis of biologically important compounds in space. It was ascertained that increase in the radiation dose and reduction of proton energy involve increase in effectiveness both of destruction of the initial aminoacid (tryptophan, tyrosine, glycine) and synthesis of the relevant dipeptide. Essential influence of mineral substrate on abiogenic synthesis of natural nucleotides under the action of diverse energy sources was pointed out
We discuss polarizing a proton beam in a storage ring, either by selective removal or by spin flip of the stored ions. Prompted by recent, conflicting calculations, we have carried out a measurement of the spin-flip cross section in low-energy electron-proton scattering. The experiment uses the cooling electron beam at COSY as an electron target. The measured cross sections are too small for making spin flip a viable tool in polarizing a stored beam. This invalidates a recent proposal to use co-moving polarized positrons to polarize a stored antiproton beam.
Because of limitation on neutron-incident data, it is difficult to obtain global optical model potential for neutrons. In contrast, there are some global optical model potentials for proton in detail. It is interesting to convert the proton-incident global optical potentials into neutron-incident ones. In this study we introduce (N-Z)/A dependent symmetry potential terms into the global proton-incident optical potentials, and then obtain neutron-incident ones. The neutron potentials reproduce total cross sections in an acceptable degree. However, a comparison with potentials proposed by other authors brings about a confused situation in the sign of the symmetry terms. (author).
It is built and tested a transition radiation detector (TRD) to discriminate positrons from protons in the balloon flight TS 93 experiment. It is presented the TRD performance using flight data obtaining a proton-positron rejection factor of the order of 10{sup -3}. During the 24 hour flight, the data in the momentum range 4-50 GeV/c are collected. Using the TRD together with the Silicon calorimeter, it is achieved an overall rejection factor of about 10{sup -5} of positron against the proton background over the entire momentum range.
Recently, organic semiconducting materials have gained a broad interest due to their potential for organic electronic devices such as organic light emitting diode (OLED), organic photovoltaic devices and organic field-effect transistors (OFETs). Optical properties of organic semiconducting materials are important for practical application. For example, the power conversion efficiency of organic photovoltaic devices is mainly affected by absorption properties of organic materials. Proton irradiation is one of the efficient methods to change the optical properties of organic materials. In this paper, we investigate the changes of optical properties of various polymers using the proton irradiation.
The NuMI proton beam at Fermilab currently delivers 120 GeV protons to the neutrino production target with design beam power capability to 400 kW. Upgrade capability to 700 kW is being prepared, with planning toward delivering 2.3 MW beam provided by the Project X accelerator upgrade plan. We report on the system of beam diagnostics and control used in operation of the NuMI beam. Also considered are the steps to provide a robust system for transport and targeting beam of 2 MW and beyond.
Characterization of high temperature superconducting film and bulk samples has been carried out using 2 MeV [alpha]-particle Rutherford backscattering, 2.4 MeV proton elastic scattering, 2.4 MeV proton-induced x-ray emission, 9 MeV proton induced [gamma]-ray emission and 100 MeV iodine elastic recoil detection analysis techniques. The objective was to compare different ion beam based techniques for: (i) compositional analysis; and (ii) consistency of the results obtained for samples prepared using similar preparation methodology. (author).
Decay sequences based on the 1/2/sup +/(660) proton orbital have been identified in /sup 171/Ta and /sup 177/Re based on spin, parity, and large alignment. This decay sequence is observed higher in energy than predicted in cranking calculations based on modified oscillator potentials. Similarly known 1/2/sup -/(541) decay sequences in these and other neighbouring isotopes are observed lower in energy than predicted. A reduction in the strength of the spin-orbit potential for protons is suggested as a solution to these problem.
A feasibility on the development of a high energy proton accelerator to be used for R and D in the nuclear field of korea was studied. The proposed one is a proton linac with parameters of about 1 GeV, 20 mA which can supply enough neutrons by the spallation reaction to drive a subcritical reactor. It= is expected to solve the intrinsic problem in the nuclear field such as safety, nuclear waste, proliferation and resource. The study was carried out through a multi-institutional cooperation of universities, institute and industry for a national consensus. 5 refs., 8 tabs., 8 figs. (author)
A concept of a traveling wave direct energy converter (TWDEC) is developed for 14.7-MeV fusion protons based on the principle of a backward wave oscillator. Separation of fusion protons from thermal ions is accomplished by using ExB ion drift. Energy conversion rate up to 0.87 is attained by applying three-stage modulation of the proton beam. A one-dimensional particle-circuit code is developed to examine self-excitation of the traveling wave and its stability under loading. Electrostatic wave with a fixed frequency is excited spontaneously, and stability of the wave is ensured under loading. (author).
The available experimental data on the (/sup 3/He,n) reaction between the ground states of even-even nuclei and lowest 1/2/sup -/ levels of odd-A nuclei in the Aapprox.=100 region are analyzed in a systematic way by the DWBA. The deduced relative intensities of these two-proton transfers, and their uncertainties, are compared to the predictions of various nuclear models. In particular, the influence of the finite dimension of the configuration space available to the transferred protons, and of the blocking effect of a 2p1/2/sup -/ proton, are examined. (orig.).
The main objective of the present study is twofold: (i) to analyze thermal loads of the geothermally and passively heated solar greenhouses; and (ii) to investigate wind energy utilization in greenhouse heating which is modeled as a hybrid solar assisted geothermal heat pump and a small wind turbine system which is separately installed in the Solar Energy Institute of Ege University, Izmir, Turkey. The study shows 3.13% of the total yearly electricity energy consumption of the modeled system (3568 kWh) or 12.53% of the total yearly electricity energy consumptions of secondary water pumping, brine pumping, and fan coil (892 kWh) can be met by using small wind turbine system (SWTS) theoretically. According to this result, modeled passive solar pre heating technique and combined with geothermal heat pump system (GHPS) and SWTS can be economically preferable to the conventional space heating/cooling systems ...
The trade-off which must be established between the various functions of pumped-storage plants is examined. A compromise between supply security and economic planning can be found only by coordinated planning of pumped-storage units and thermal generation plants. A model used by Electricite de France (EDF) to ensure optimized daily planning of thermal and pumped-storage units is described. The model, called the DEMETER model, ensures the optimization of the daily planning of thermal and pumped-storage plants. The model iterates between two levels: coordination where the prices of the generated energy and the operating reserve are determined to adjust generation to load and keep a sufficient reserve; and decomposition where the schedule of each unit is optimized on the basis of the above prices and taking into account local constraints such as unavailability, and minimum shut down time. The role of EDF ...
The large number of forms and types of pump equipment in common use have different purposes and varying application requirements. This text has been prepared to bring together necessary information for those who are required to select and apply pumps in systems for all kinds of fluids and purposes. It is not a design manual. It limits the discussion of design to those factors which are necessary for an understanding of pump operation. The book contains not only descriptive information of many types of designs, but also the effect of design variation on use, economy, and reliability. Systems, an integral part of application, are discussed, so that the user of such equipment may properly select and install machines to reliably and economically satisfy his requirements. Reading of appropriate sections of the text will indicate possible problems to be avoided, and economics to be gained. The engineering design of ...
The effects of the contrast of the pump field interference pattern, that is, the effectiveness of the dynamic amplitude-phase grid, and various optical arrangements on the lasing efficiency and tuning range of a dynamic distributed-feedback dye laser are investigated. It is shown that the proper choice of prism apex angle, prism material and dye solvent in a laser in the range 400-1000 microns pumped by two beams of different intensity directed through the congruent sides of an isosceles prism in contact with the active medium solution on its third side can lead to optical losses of less than 2% from the boundaries of the prism. Measurements of polymethine dye laser efficiency and tuning range as a function of the relative intensity of the two ruby-laser pump beams reveals that as the contrast of the pump beam interference pattern decreases, the tuning range remains practically constant and the ...
W. Wayne Scott and R. G. Alsmiller, Jr. ABSTRACT. Comparisons of the results obtained for a hypothetical problem with four different proton penetration ...
We develop the formalism of a unified semi-microscopic description of low-energy proton and {alpha}-particle interaction with nuclei. We analyze elastic and inelastic proton scattering at the energy 25.05 MeV and {alpha}-particle scattering at the energy 104 MeV by the {sup 90}Zr nucleus. Information is obtained on differences in the deformation of the proton and neutron distributions. We study the energy dependence of the semi-microscopic {alpha}-particle potential including the energy dependence of the potential geometry.'' We analyze the change in angular distributions of elastically scattered {alpha} particles with increase of energy and the contribution to the scattering cross section from nucleon-nucleon correlations.
The process of radiation induced electron capture by protons or deuterons producing new ultra low momentum neutrons and neutrinos may be theoretically described within the standard field theoretical model of electroweak interactions. For protons or deuterons in the neighborhoods of surfaces of condensed matter metallic hydride cathodes, such conversions are determined in part by the collective plasma modes of the participating charged particles, e.g. electrons and protons. The radiation energy required for such low energy nuclear reactions may be supplied by the applied voltage required to push a strong charged current across a metallic hydride surface employed as a cathode within a chemical cell. The electroweak rates of the resulting ultra low momentum neutron production are computed from these considerations.
The energy spectra and angular distributions of proton emission in a reaction of {sup nat}Fe(n,xp) at a neutron energy of 14.6 MeV are measured by the University of Science and Technology of China multitelescope system. The double-differential cross sections of 16 reaction angles from 25 to 164.5 deg are obtained in this measurement. The statistical errors are reduced largely because of the thick target used. The angular distributions show a slightly energy-dependent forward-backward asymmetry. The angle-integrated proton spectrum is compared with theoretical calculations and other results. The total proton-emission cross section is in fair agreement with the prediction and evaluation.
TiH{sub 2} and TiD{sub 2} thick targets were bombarded with 100 to 200 keV protons or deuterons. Evidence for nuclear reactions was obtained by means of a surface barrier particle detector. Deuteron irradiation of TiD{sub 2} produced these observations: copious {approx}2.5 MeV neutrons and {approx}3 MeV protons from direct D-D reactions; gamma rays from p,{gamma} and n,{gamma} reactions; {approx}14 MeV protons from the secondary d({sup 3}He, p){alpha} reaction; and a signal between {approx}6-12 MeV that Kasagi et al. has tentatively identified as protons from the fusion of three deuterium nuclei. However, this signal has in it a strong interference signal from either neutrons or gamma rays that directly deposit energy in the detector. This interference spectra was measured by placing a thick absorber in front of the detector that stops up to 20 MeV protons, but not gamma rays or ...
Research conducted since the last progress report includes the synthesis and characterization of twenty three novel proton-ionizable crown ether compounds. Metal ion complexation behavior of new and previously-synthesized proton-ionizable crown ether compounds has been probed by solvent extraction and transport across polymer-supported liquid membranes. The behavior of neutral polyether and proton-ionizable polyether ligands in polymeric membrane electrodes has been assessed. Studies of the use of proton-ionizable crown ethers for separation of lithium isotopes were initiated. Also, the thermodynamics of interactions between alkali metal cations and ionized crown ethers have been probed by titration calorimetry. 10 refs., 1 tab.
The behavior of proton transfer facilitated by a novel thiazole derivative, N-methyl-4-(4-phenoxyphenyl)thiazol-2-amine (MPPT), across the water/1,2-dichloroethane (1,2-DCE) interface was investigated electrochemically. The ionic partition diagram for MPPT was obtained from interpretation of the cyclic voltammograms. The apparent partition coefficient of MPPT was evaluated by the shaking-flask method under experimental conditions, while that for the protonated form of MPPT was calculated from its transfer potential obtained from the ionic partition diagram. It was suggested that the mechanism for transfer of MPPT across the water/1,2-DCE) interface depends on the pH of the aqueous phase. The parameters of the facilitated proton transfer across the water/1,2-DCE interface were evaluated as ...
Neutron time-of flight spectra were measured from 90 MeV protons and 140 MeV alpha-particle bombardment of Al, Ni, Zr, and Bi at laboratory angles between 20/sup 0/ and 130/sup 0/. The proton induced neutron spectra reveal three distinct energy regions; a low energy evaporation region, a high-energy region dominated by quasi-free scattering processes and an intermediate-energy region dominated by multi-step, pre-equilibrium processes. In the latter two regions, the spectra show strong angular dependence. The alpha-induced neutron spectra show these same distinct energy regions plus an exponential fall-off above the beam energy per nucleon. The high-energy portions of the forward-angle neutron and proton cross sections are in ratios consistent with the assumption that single nucleon-nucleon scattering dominates. For heavy-mass targets, the low-energy evaporation regions show neutron yields larger than ...
Neutron time-of flight spectra were measured from 90 MeV protons and 140 MeV alpha-particle bombardment of Al, Ni, Zr, and Bi at laboratory angles between 20"0 and 130"0. The proton induced neutron spectra reveal three distinct energy regions; a low energy evaporation region, a high-energy region dominated by quasi-free scattering processes and an intermediate-energy region dominated by multi-step, pre-equilibrium processes. In the latter two regions, the spectra show strong angular dependence. The alpha-induced neutron spectra show these same distinct energy regions plus an exponential fall-off above the beam energy per nucleon. The high-energy portions of the forward-angle neutron and proton cross sections are in ratios consistent with the assumption that single nucleon-nucleon scattering dominates. For heavy-mass targets, the low-energy evaporation regions show neutron yields larger than proton ...
We measured neutron time-of-flight spectra from 90 MeV protons and 140 MeV alpha particles bombarding thin targets of Al, Ni, Zr, and Bi at laboratory angles between 20_0 and 135_0. The low-energy (5 to 45 MeV) portions of the spectra were measured with 5 cm diameter by 5 cm deep NE-213 counters at 1 m flight paths with n-#betta# pulse-shape discrimination. The high-energy (35 to 150 MeV) portions of the spectra were measured with 12.7 cm diameter by 10.2 cm deep NE-102 counters at flight paths of 2.0 to 5.0 m. The proton-induced measured neutron spectra reveal three distinct energy regions: a low-energy evaporation region, a high-energy region dominated by the quasifree scattering process, and an intermediate-energy region dominated by multistep, preequilibrium processes. In the latter two regions, the spectra show strong angular dependence. The alpha-particle induced neutron spectra show these same distinct energy regions plus an exponential ...
By method of transmission electron microscopy and measuring of microhardness the peculiarities of influence of radiation defect clusters on molybdenum radiation hardening along range path of protons with 30 MeV initial energy are studied. Decrease effect of hardening growth value and even its absence depending on irradiation dose in the range of 10-20 MeV proton energies in presence of high density of radiation defect dispersed clusters is revealed. It is shown experimentally that this effect is connected with accumulation of hydrogen up to not very high concentrations (not more than 5x10"-"4 at.%) at the expense of elastic and inelastic proton scattering. 5 refs.; 5 figs.
Proton exchange membrane (PEM) fuel cells are energy sources that have the ... for H2 /02 PEM fuel cells because their catalysts have properties suitable for 0 ...
Doubly decoupled structures in doubly odd deformed nuclei are reexamined and shown to be composed of a pseudo-spin aligned neutron and a decoupled proton. (orig.).
Doubly decoupled structures in doubly odd deformed nuclei are reexamined and shown to be composed of a pseudo-spin aligned neutron and a decoupled proton. (orig.).
A review of the deep-level defects observed in both electron- and proton-irradiated GaAs solar cells is presented. Studies of the effects of periodic and continuous thermal annealing on the radiation-induced electron and hole traps and the recombination parameters in GaAs solar cells were made for a wide range of electron and proton energies, fluence, annealing temperature and annealing time. A refined model for numerical simulations of the displacement damage was developed for computing the defect density and the cell parameters in the electron- and proton-irradiated GaAs solar cells. Excellent agreement was obtained between the calculated values and the experimental data for the proton-irradiated GaAs solar cells. (orig.).
Copper deficiency is associated with impaired brain development and mitochondrial dysfunction. Perinatal copper deficiency was produced in Holtzman rats. In vivo proton NMR...Full Text Available
We study the characteristics of cyclotron wave-particle interaction in a typical hydrogen plasma. The numerical calculations of minimum resonant energy Emin, resonant wave frequency ?, and pitch angle diffusion coefficient D?? for interactions between R-mode/L-mode and electrons/protons are presented. It is found that Emin decreases with ? for R-mode/electron, L-mode/proton and L-mode/electron interactions, but increase with ? for R-mode/proton interaction. It is shown that both R-mode and L-mode waves can efficiently scatter energetic (10 keV-100 keV) electrons and protons and cause precipitation loss at L=4, indicating that perhaps wave-particle interaction is a serious candidate for the ring current decay. (authors)
At a military base in the Southeastern US, an energy services company (ESCO) has proposed to retrofit more than 1,000 family residences with geothermal heat pumps as part of an energy savings performance contract (ESPC). Each residence is to have one heat pump with its own ground heat exchanger consisting of two or more vertical bores. A design firm hired by the ESCO sized the heat pumps to meet peak cooling loads, and sized the borefields to limit the maximum entering water temperature (EWT) to the heat pumps to 95 F (35 C). Because there is some disagreement in the geothermal heat pump industry over the peak temperature to be used for design (some designers and design manuals recommend temperatures as low as 85 F[29 C], while equipment manufacturers and others specify temperatures of 100 F[38 C] or higher) the authors were requested to examine the designs in detail to determine ...
It is shown that elastic scattering data for protons of 100-200 MeV are consistent with an absorptive potential that is stronger in the nuclear interior and of the slightly shorter range than is usually assumend, which is more in agreement with microscopically calcuated potentials. Consequences for certain (p,p') and (e,e'p) reactions are shown. (orig.).
We irradiated proton beams on the ears of rabbits and the Harding-Passey mouse melanoma and observed their morphological change. We used 52 MeV proton beams from the INS-FM cyclotron. We adjusted the energy of the proton beams to be at the plateau part of the Bragg curve, at the half-way point of the Bragg peak, and at the Bragg peak. The amount of radiation was 5000rad in each case. The Harding-Passey mouse melanoma was transplanted into the subcutan of a three week old mouse. In this experiment, we used tumors, the diameter of which grew up to 1.5-2cm in 2-3 weeks after the transplantation. Using the jroscope, we observed both lightly and severely damaged cells. Using proton irradiation with the Bragg peak located at depth of 1mm in the rabbit's ears, we studied the change in the tissue. Irradiated epidermis fell off and was eroded because of radiation damage, but the rear surface of the ...
The thermal stability of diffusion barriers is explored on the basis of Bi films at different expedients of deriving of films. The examinations were conducted on the electrostatic accelerator at KNU of name Karazin V.N. under conditions of an isothermal bakeout directly under a proton beam of 1,85 MeV energy.
Scheme of theoretical method of molecular configuration definition for small organic molecules in solution has been presented. The method bases on measurements of nuclear Overhauser effects for proton-proton interactions and molecular mechanics calculations. 3 refs, 1 fig.
The proton therapy gives an irradiation adapted to the shape and the depth of tumors ( eyes, head and neck) with a millimetric, even sub millimetric precision for the ophthalmological tumors. It is equally an excellent tool for the pediatrics tumors. For numerous treatments in France the proton therapy is associated to the photons treatments (x radiation). however, others physical treatments could modulate the medical offer, such thermal therapy or treatments by ultrasonic waves. (N.C.)
The constancy in excitation energy of the lowest 2/sup +/ state in the Sr isotopes across the N=56 subshell closure is shown to result from a reduction in the 2psub(1/2)-2psub(3/2) proton spin-orbit splitting as the 2dsub(5/2) neutron orbital is filled.
The wavefunction of a particle extends into the classically forbidden barrier region of the potential energy surface. The consequence of this partial delocalisation is the phenomenon of quantum tunnelling, an effect which enables a particle to penetrate a potential barrier of magnitude greater than the energy of the particle. The tunnelling probability is an exponential function of the particle mass. The effect is therefore an important contribution to the behaviour of light atoms, in particular the proton. The hydrogen bond has long been appreciated to be an essential component of many biological and chemical systems, and the proton transfer reaction in the hydrogen bond is fundamental to many of these processes. The proton behaviour in the hydrogen bonds of benzoic acid, acetylacetone and calix-4-arene has been studied. A variety of techniques, both experimental and computational, were adopted for the study of the three ...
It is shown that elastic scattering data for protons of 100-200 MeV are consistent with an absorptive potential that is stronger in the nuclear interior and of the slightly shorter range than is usually assumend, which is more in agreement with microscopically calcuated potentials. Consequences for certain (p,p') and (e,e'p) reactions are shown.
A tiered communications architecture for managing network traffic in a distributed system. Communication between client or control computers and a plurality of hardware devices is administered by agent and monitor devices whose activities are coordinated to reduce the number of open channels or sockets. The communications architecture also improves the transparency and scalability of the distributed system by reducing network mapping dependence. The architecture is desirably implemented in a proton beam therapy system to provide flexible security policies which improve patent safety and facilitate system maintenance and development.
At the beginning of the seventies, physicists discovered a new scale in the matter structure. Protons and neutrons, components of the atomic nucleus, seemed to be constituted by even more elementar particles: the quarks. But while they seemed to move freely inside the protons, it was impossible to isolate one of these quarks. The Nobel Prize for physics rewarded the explanation of this phenomenon (3 pages)
A study of the 150-300 keV proton beam transmission through glass (borosilicate) tapered capillaries with different diameters of the input and output of the capillary was performed. The focusing effect was observed. The areal density of the transmitted beam is enhanced by approximately 20 times. It was shown that changing a taper angle from 0.5 deg to 1.7 deg evidences the increase of the transmission coefficient more than by 300 times keeping the initial energy spectrum of ions. (author)
Purpose: This study presents a dosimetric optimization effort aiming to compare intensity-modulated (IM) X-rays and IM protons in 4 different orbital and paraorbital tumors. These are most challenging targets for standard radiotherapy due to their close relationship with the eyes and related structures. Methods and Materials: A primary orbital lymphoma, an optic nerve meningioma, a sphenoidal ridge meningioma protruding into the orbit, and a pediatric parameningeal paraorbital rhabdomyosarcoma were selected for the purpose of this study. Planning target volumes (PTVs) and organs at risk (OAR) were defined in each patient CT data set for each tumor site. IM X-ray and IM proton three-dimensional treatment plans were implemented. The following total tumor doses were prescribed: 30 Gy for the orbital lymphoma, 54 Gy for both meningiomas, and 50.4 Gy for the rhabdomyosarcoma case. Dose-volume histograms (DVHs) were obtained for all targets and OAR ...
A polarized proton physics run took place during January, 1988, at the Brookhaven AGS. It is the purpose of this paper to review the tune-up period preceding that run. This was the third such run at the AGS; the others occurred in June of 1984 and February of 1986. Some comparisons will be drawn among these. A thorough review of the history and hardware associated with the acceleration of polarized protons at the AGS can be found in the proceedings of the last meeting of this group at Protvino and will not be repeated here. 2 refs., 6 figs., 1 tab.
Peak at 60 deg in angular proton distribution in inelastic pion-carbon interactions is interpreted as generation of Cherenkov gluon radiation in flucton, passing into the shock wave with successive nucleus decay. Investigation of hadron-nuclear interactions with anomalous peak in angular proton distribution can be used as additional means for study both of flucton and mechanism of hadron-nuclear interactions. 5 refs.
A "9"2Mo beam with an energy of E/A=70 MeV has been used to produce new isotopes near the proton drip line. The Michigan State University National Superconducting Cyclotron Laboratory A1200 fragment separator was used to detect the new isotopes "7"8Y, "8"2Nb, "8"5Mo, "8"6Tc, and "8"9","9"0Ru.
A {sup 92}Mo beam with an energy of {ital E}/{ital A}=70 MeV has been used to produce new isotopes near the proton drip line. The Michigan State University National Superconducting Cyclotron Laboratory A1200 fragment separator was used to detect the new isotopes {sup 78}Y, {sup 82}Nb, {sup 85}Mo, {sup 86}Tc, and {sup 89,90}Ru.
Monte Carlo calculations performed to validate observed capture reaction rates of "1"2"9I and "2"3"7Np were in a reasonable agreement with experimental data obtained by the Joint Institute for Nuclear Research. The most significant discrepancy between the measurements and calculations (within a factor of 3) was observed for the NpO_2 sample and Pb target at 3.7 GeV proton energy
"La Universidad de Valencia tiene avanzado el diseno de un acelerador lineal de protones, cuya culminacion depende del compromiso del Consell en sufragar la plantilla que necesitaria el centro para estar operativo" (1 page).
Ksub(#beta#)/Ksub(#alpha#) X-ray intensity ratios have been measured for various elements between Z = 29 and Z = 79 for incident proton energies of 23.6, 32.1 and 43.6 MeV. The results yield no evidence for a variation in ratio with particle energy. (orig.).
The Ksub(#beta#)/Ksub(#alpha# 12) x-ray intensity ratio of the Si K spectrum was measured for proton impact on Si0_2 in the energy range 300-800 keV. An energy dependence of the intensity ratio was found and an explanation is given in terms of multiple ionisation. (author).
Cross sections for elastic scattering of 12 GeV protons from /sup 40/Ca nuclei have been calculated using the flucton model. The influence of the collective flucton nucleon correlations on the calculated cross sections is examined. The calculated cross sections are in significant disagreement with the experimental data. This may be considered as an argument against the flucton model.
Cross sections for elastic scattering of 12 GeV protons from "4"0Ca nuclei have been calculated using the flucton model. The influence of the collective flucton nucleon correlations on the calculated cross sections is examined. The calculated cross sections are in significant disagreement with the experimental data. This may be considered as an argument against the flucton model. (orig.).
Differences of the deformation parameters for the 2"+_1 states of even-even spherical nuclei extracted from electromagnetic excitation #beta#sup(em)_2 and from proton scattering #beta#sup(pp')_2 are discussed. It is found that the ratio #beta#sup(pp')_2/#beta#sup(em)_2 is equal to about unity and that there is a small isotope dependence for several incomplete shell nuclei. (orig.).
The authors present some precision measurements on electroweak physics performed at the Tevatron collider at Fermilab. Namely they report on the boson-pair production cross sections and on triple gauge boson couplings using proton anti-proton collisions collected by the CDF and D0 experiments at the center-of-mass energy of 1.96 TeV. The data correspond to an integrated luminosity of up to 324 pb{sup -1}.
The K"+- and K"-meson cumulative production cross sections are measured at 119"0 in the laboratory system on nuclei Be, Al, Cu and Ta bombarded by 10 GeV protons. Spectra of the K"-mesons consisting of only sea quarks show universal features characteristic of the spectra of cumulative particles, which contain valence quarks. Evidence is obtained for the fact that the energy density in a flucton can exceed the mean nuclear density by an order of magnitude.
Independent calculations of the antiproton-to-proton ratio by Gaisser and Maurer and by Badhwar et al. have produced conflicting results which obscure the interpretation of recent measurements of cosmic ray antiprotons. A detailed reexamination of these calculations has been performed and these differences have been resolved. We find that the first calculation was essentially correct and the reported fluxes of antiprotons are significantly higher than expected for secondary antiprotons in conventional models of cosmic ray propagation, as indicated by other recent calculations.
The available measurements on the cosmic-ray antiproton/proton ratio show an excess of antiprotons above predictions derived in the framework of the standard picture of cosmic-ray origin and propagation. Calculations are performed of the production from collisions of cosmic rays with the interstellar gas under the condition of distributed reacceleration. It could be shown that the calculated antiproton/proton ratio is enhanced compared to that derived from the leaky box model, but it remains difficult to bring it into agreement with the data by reasonable astrophysical assumptions. 15 references.
The work presented in part 1 of this study established that the sorption of anhydrous HX into dehydrated Na{sub 56}Y progresses through a sequence of steps involving HX ionization and charge separation, oxygen framework protonation, formation of {alpha}-cage confined cation-anion contact ion pairs, and proton solvation by HX. A logical extension, which is the subjected of this study, concerns the effect of extraframework alkali metal cation type (M = Li{sup +}, Na{sup +}, K{sup +}, Rb{sup +}, Cs{sup +}) on the sorption process. The question of the acidity of proton-loaded zeolites compared to Broensted acid zeolites is addressed by using probe reactions with weak bases like ethane and cyclopropane. Additional insight into these systems is also obtained from a quantitative comparison of the kinetic and thermodynamic activation parameters for the dehydrohalogenation of proton-loaded zeolites exemplified ...
We examined whether proton magnetic resonance spectroscopy (MRS) could provide accurate information on histological grade and cell proliferation in astrocytomas. We studied 23 patients with astrocytomas: five grade II, 10 grade III and eight with grade IV (glioblastoma multiforme). We performed proton MRS and determined the Ki-67 labeling index (LI), a tumour proliferation marker, in the same areas of the astrocytomas, and examined the statistical relationship between proton MRS and Ki-67 LI. The N-acetylaspartate (NAA)/creatine-phosphocreatine (Cr) and NAA/choline (Cho)-containing compound ratios were always significantly lower and the Cho/Cr ratios significantly higher than those for normal brain. The Cho/Cr ratio correlated positively and the NAA/Cho ratio inversely with Ki-67 LI. These findings suggest that the Cho signal in proton MRS reflects cellular proliferation. In Kaplan-Meier survival ...
Protonic ceramic membrane fuel cells (PCMFCs) based on proton-conducting electrolytes have attracted much attention because of many advantages, such as low activation energy and high energy efficiency. A stable, easily sintered perovskite oxide BaCe_0_._5Zr_0_._3Y_0_._1_6Zn_0_._0_4O_3_-_#delta# (BCZYZ) as electrolyte for proton-conducting solid oxide fuel cells (SOFCs) with Sm_0_._5Sr_0_._5CoO_3_-_#delta# (SSC) composite cathode is investigated. By fabricating thin membrane BCZYZ electrolyte (#approx#20 #mu#m) synthesized by a modified Pechini method on NiO-BCZYZ anode support, PCMFCs are assembled and tested by selecting SSC perovskite cathode with high mixed ionic and electronic conductivities. An open-circuit potential of 1.015 V, a maximal power density of 528 mW cm"-"2, and a low polarization resistance of the electrodes of 0.15 #OMEGA# cm"2 is achieved at 700 "oC. The results indicate that BCZYZ ...
The intensity of erbium up-conversion luminescence could be limited by a saturation effect due to increased pump power. We studied the luminescence saturation of the 550 nm emission on erbium-doped, SiO_2-TiO_2 sol-gel powders under pulsed excitation at 979 and 1532 nm. From the latter, the up-converted luminescence intensity decreased with increasing excitation power, whereas no saturation was observed at 979 nm excitation. We proposed that the saturation effect is determined by the pump power, the erbium content and the lifetime of the corresponding first excited states at different pumping schemes.
In many regions of the world, flooded mines are a potentially cost-effective option for heating and cooling using geothermal heat pump systems. For example, a single coal seam in Pennsylvania, West Virginia, and Ohio contains 5.1 x 1012 L of water. The growing volume of water discharging from this one coal seam totals 380,000 L/min, which could theoretically heat and cool 20,000 homes. Using the water stored in the mines would conservatively extend this option to an order of magnitude more sites. Based on current energy prices, geothermal heat pump systems using mine water could reduce annual costs for heating by 67% and cooling by 50% over conventional methods (natural gas or heating oil and standard air conditioning).
A brief description is given of the physico-chemical parameters characterized a hot water geothermal reservoir and of its exploitation by means of single or coupled (doublet) wells. The technical aspects of geothermal heat to the users is then discussed, beginning with corrosion of materials caused by seven main agents: oxygen, hydrogen sulphide, carbon dioxide, ammonia, hydrogen, sulphates and chlorides. A brief mention is made of scaling due to calcium carbonate, silica and calcium sulphates. The basic components of a geothermal plant for non-electric uses are then discussed: production pumps, surface pipelines, heat exchangers, heat pumps and reinjection pumps. The advantages and disadvantages of the different equipment and materials used in the geothermal sector are also presented. A list is also given of the criteria used in the energy and economic balance of a geothermal operation. (author). 24 refs, 13 figs, 2 tabs.
We study spontaneously generated entanglement (SGE) between two identical multilevel atoms in free space via vacuum-induced radiative coupling. We show that the SGE in two-atom systems may initially increase with time but eventually vanishes in the time scale determined by the excited state lifetime and radiative coupling strength between the two atoms. We demonstrate that a steady-state SGE can be established by incoherently pumping the excited states of the two-atom system. We have shown that an appropriate rate of incoherent pump can help producing optimal SGE. The multilevel systems offer us more chanel to establish entanglement. The system under consideration could be realized in a tight trap or atoms/ions doped in a solid substrate.
Currently the construction of small-scale hydroelectric and pumped storage plants is booming in the USA. The technology is attractive because of its relatively cheap construction methods and operation. Electric utilities are seeing it as a viable source of peaking power and a means of system regulation. Two schemes are described. One is a high-head/small flow river project designed to generate 3.5 MW and is about to come on line having overcome tight environmental and commercial constraints. The second is a pumped-storage project using two man-made reservoirs with an average elevation difference of 1280 ft. It is deemed to be of minimum environmental impact construction and good physical characteristics. Completion is hoped for by 1995 and the plant will deliver 1000 MW. (UK)
Repetitively Q-switched operation of an end-pumped Nd:YAG laser over the range of 200 Hz to 3 kHz using an intracavity chopper is demonstrated. Performance is shown to be comparable to that achieved with an acousto-optic Q switch under similar conditions. The advantages and limitations of the mechanical Q switch are described. Parametric variations of output coupling and pump power lead to an extended empirical description of repetitively Q-switched laser operation. The insertion loss as a function of aperture-edge penetration into the resonator is reported, and a definition of the mechanical Q-switch opening time is provided. Q-switched pulsewidths as short as 35 ns were obtained for the Nd:YAG laser, with a peak power-enhancement factor in excess of 300. PMID:20862099
Purpose: To stably control the reactor water level so as not to cause excess water feeding in a BWR type reactor. Constitution: A flow control valve is disposed to the exit of a feedwater pump for a nuclear reactor and the valve is controlled by a flow regulator to maintain the water level constant in the reactor. A signal from a water level controller is inputted to the flow regulator to thereby control the flow rate control valve. In this case, the flow regulator remains in a saturated state just after the starting of the feedwater pump, in which the pump flowrate is at 100% to result in an excess water feeding condition. In view of the above, a feedback circuit is provided to the flow regulator so that the saturated state is eliminated and the water feeding can be controlled directly from the water level controller. (Kamimura, M.).
During a regular inspection of the Boiler Auxiliaries at one of the Dutch Electricity Production Companies serious cracks were found in the cover and casings of the feed water circulation pumps in two units after 108.000 and 122.000 hours of boiler operation. Kema Laboratories carried out Failure analyses on boat samples at the cracked areas. Corrosion fatigue cracking was found on the inner side of the GS-24CrNiMo325 casing. Shop Weld repairs were carried out using a newly developed mechanized Plasma Welding Technique. The repaired feed water circulation pumps showed no problems alter several years of operation. The costs of repair were substantially lower than the costs of replacement. (orig.) 3 refs.
The invention concerns a device for the energy-saving heating of fuel in the supply pipe to an internal combustion engine to regain energy from the fuel itself, particularly but not exclusively for a Diesel engine. A part of the quantity of heat added to the fuel between the tank and the injection nozzles is given up by excess fuel not to the tank, but to the fuel lifted upstream of the injection pump. The device is characterised by the fact that it has a heat exchanger, which absorbs heat from the fuel at the level of the injection pump or upstream of it, and takes this to the fuel above the injection pump. The heat exchanger is preferably mounted upstream of a filter and close to it. A bridging pipe, which may be integrated in the heat exchanger, permits the heat exchanger to be short-circuited depending on the fuel temperature.
The study discussed relates to the design and development of a process consisting of combining a reversible geothermal heat pump with thermal solar collectors for building heating and cooling and the production of domestic hot water. The proposed process, called GEOSOL, has been installed in a 180 m{sup 2} private residence in 2004. This installation is the subject of long-term experimental follow-up to analyse the energy-related behavior of the installation at all times of the year. In addition, different configurations of this combined system (geothermal heat pump and thermal solar collectors) have been defined and will be simulated numerically using TRNSYS software. A comparative analysis of these different alternative versions will be conducted to determine the best configuration(s) of the GEOSOL process in terms of energy, economical and environmental performances. (author)
The low-power operation of a semiconductor buried-heterostructure Raman laser is reported. We are developing these devices for very wide-band optical communication in the terahertz frequency region. It has a structure with a GaP active layer and Al{sub {ital x}}Ga{sub 1{minus}{ital x}}P cladding layers, which are grown by the temperature-difference method under controlled vapor pressure. By making the stripe width 30--40 {mu}m, we have obtained a threshold pump power of 500 mW. A low-threshold semiconductor Raman laser can be pumped by semiconductor injection lasers. We have measured the optical loss of the waveguide and detected the contribution from scattering and leakage at heterointerfaces.
The objective of this study is to establish a construction plan for vibration analysis system of HANARO's rotating machinery. To achieve this purpose, as a first step, the references related to the vibration analysis system for the rotating machinery were investigated. In addition, to verify the possibility of condition monitoring of the pumps, vibration signals obtained from the vibration monitoring system were analyzed. The results show that using the accelerometers mounted on the bearing locations of the pumps can monitor the current status of the pump such as unbalance, misalignment, and bearing condition. Based on the results of this study, the construction plans for the vibration analysis system of HANARO have been established. The hardware of the vibration analysis system will be installed by the end of this year. It is expected that the developed vibration analysis system can be utilized for the realization ...
Striking differences in differential reflectance and carrier relaxation in In0.4Ga0.6As and In0.4Ga0.6As0.98N0.02 single quantum wells (SQWs) were studied using ultrafast time-resolved photoreflectance. Even with extremely thin SQW of only 60 A within 3000 A wide GaAs confining layers, negative and positive differential reflectance was observed for the excitation photon energy far above the bandgaps at 820 and 880 nm for both samples. Due to absorption by the GaAs confining layer, the peak differential reflectance pumped at 820 nm is an order of magnitude larger than that pumped at 880 nm; and it is larger for InGaAs SQWs than for InGaAsN SQWs. The shorter carrier lifetimes of these samples result from carrier-carrier scattering as pumped at both wavelengths. The longer carrier lifetime as pumped at 880 nm is due to hot phonon decay in InGaAs but may be due to stimulated emission in InGaAsN. The results ...
Investigations of superdense compression touch on such problems as ultrahigh-frequency oscillations of matter in the generation of gravitational waves, the powerful pumping of hard coherent radiation, and the laboratory simulation of stellar interiors. This paper reviews the theory of supercompression and discusses some experiments involving multifoil collision supercompression.
Background and purpose:Diphenyleneiodonium (DPI) is often used as an NADPH oxidase inhibitor, but is increasingly being found to have unrelated side effects. We investigated its...Full Text Available
Japan has upwards of 40 pumped storage plants in operation and new river sites are becoming scarce, but peak demand is still rising. A plant under construction in Okinawa offers a solution: make use of the head between the coastal cliffs and sea level, using seawater as the medium. (author)
Pumped storage plants participate in two structurally different markets: the market for scheduled energy (also known as spot market) and the reserve market. In order to achieve the best possible plant scheduling in terms of revenues the marketing of the available capacity from pumped storage plants needs to be optimised in both markets. Moreover, due to the abilities for providing reserve, pumped storage capacities within an existing power plant portfolio can lead to synergies for the whole portfolio. The optimised combined participation of a power plant in both spot and reserve market as well as the coherent portfolio effect are considered as particular challenges in energy economic assessments, e.g. in the light of investment decisions. Based on an extension project and in cooperation with RWTH Aachen University an optimised combined participation of a power plant in both markets was simulated for the first time, thereby ...
The heating system of the `Centre integre de mecanique industrielle de la Chaudiere`, in Saint-Georges, Quebec, is based on a solar wall and a geothermal heat pump with a glycol/water mixture circulating in 44 wells that are 100 m deep. With installation costs below $25 per sq.m, more than 85 per cent of the heating needs of the 9500 sq.m centre were supplied by geothermal power. The geothermal heat pump is composed of a well field and two 211-kW cooling units, each equipped with four coiled compressors. In winter, heat is pumped from the earth and in summer, a heat exchanger with control valves allows to heat to be dumped back into the earth. The monitoring and simulation of the system proved its efficiency, considering the climatic conditions in Quebec. The annual consumption of geothermal heating is 0.146 GJ per sq.m, which is very low compared to the consumption of electric heating (0.286 GJ per sq.m) or oil heating ...
1. In rat soleus muscle, high frequency electrical stimulation produced a rapid increase in intracellular Na+ (Na+i) content. This was considerably larger in muscles contracting without developing tension...Full Text Available
We investigated the Raman coherence characteristics of a solid hydrogen film deposited on a sapphire substrate held at 5.3 K. Using Raman coherence prepared with two single-frequency pulsed lasers, we generated the multiorder coherent Raman sidebands in solid hydrogen film. The highorder Raman sidebands were obtained under strong pumping intensities (>= 230 MW/cm{sup 2}). The generated anti-Stokes(AS)-Raman sidebands extend from the ultraviolet (292 nm for the AS5 band) to the visible (565 nm for the AS1 band) region. The multiorder Raman sideband generation is found to be due to the parametric coupling of pump and coupling lasers. The frequency conversion efficiency from pumping beams to the first AS-Raman sideband shows a maximum (14 %) at a pumping intensity of 360 MW/cm{sup 2}. From an experiment that makes the multimode probe beam beat with the prepared Raman coherence, we found that the ...
We investigated the Raman coherence characteristics of a solid hydrogen film deposited on a sapphire substrate held at 5.3 K. Using Raman coherence prepared with two single-frequency pulsed lasers, we generated the multiorder coherent Raman sidebands in solid hydrogen film. The highorder Raman sidebands were obtained under strong pumping intensities (? 230 MW/cm2). The generated anti-Stokes(AS)-Raman sidebands extend from the ultraviolet (292 nm for the AS5 band) to the visible (565 nm for the AS1 band) region. The multiorder Raman sideband generation is found to be due to the parametric coupling of pump and coupling lasers. The frequency conversion efficiency from pumping beams to the first AS-Raman sideband shows a maximum (14 %) at a pumping intensity of 360 MW/cm2. From an experiment that makes the multimode probe beam beat with the prepared Raman coherence, we found that the prepared Raman ...
Every day we are witnesses of constantly rapid increase of consumption of Electric energy in R. of Macedonia as so as in the other countries in all the world. This rapid increase of consumption of Electric energy independent of a lot of electrical units, which are applying in human life like: homes, administration and publication objects, as well as in industry. All of this conditions make us to thinking how is possible more rational consumption of electric energy in all areas in human life. One of the possible manners to reduce the consumption of electrical energy for heating and cooling is to use geothermal heat pumps. In this paper will be proposed geothermal heat pump, which is going to use the heat of earth by vertical and horizontal cupper pipe heat exchanger with data from-GHP (Geothermal Heat Pump) NORDIC, factory in Canada. Also, it will be examined all parameters and done comparison with already existing ones. It ...
The key to improving transmission-network security is faster response to contingencies. Now a new breed of pumped-storage plant - designed for ultra-fast response - may soon provide a tool dispatchers can use to improve network security. This type of plant can also substantially increase the effective capacity of existing transmission lines and improve the performance of thermal generating units. The Mt. Hope Waterpower Project, planned for Rockaway Township, NJ, 35 miles west of New York City, lies strategically adjacent to major load centers at the eastern end of the PJM control area and near the interconnection point with the New York Power Pool (NYPP). This location also is in an area deficient in significant generating facilities. Maximum design capacity of the project is 2000 MW, provided by six reversible pump/turbines, each with a nominal 340-MW rating. The upper reservoir, with a surface area of only 60 acres, provides 5000 acre-ft of ...
Isogenic strains containing insertional disruptions of 10 Haemophilus influenzae Rd genes were investigated for their effects on the susceptibility of the organism to various classes...Full Text Available
Recent developments in heat pump technology have made geothermal-based heat exchange systems particularly well-suited for the heating and cooling needs of buildings even in cold climates. The principles of geothermally-coupled heat pump heating and cooling systems were presented. Results of an in-situ study conducted by Hydro-Quebec on the efficiency of the geothermal heat pump system installed at the Saint-Hyacinthe professional school were summarized. This investigation was meant to be a case study of the applicability of these new technologies to the needs of the Quebec market. After the first year of service, the Saint-Hyacinthe system clearly demonstrated its cost effectiveness over conventional systems. It was predicted that geothermal heat pump systems will gain in popularity in Quebec because they can fully meet the heating and cooling needs of public buildings at considerable cost reductions, ...
BackgroundCalcium homeostasis is a known target of several environmental toxicants including lead and mercury.ObjectiveOur goal was to determine...Full Text Available
A multi-faceted research program has been performed to investigate in detail several aspects of free and forced convective cooling of underground electric cable systems. There were two main areas of investigation. The first one, reported in Volume 1, dealt with the fluid dynamic and thermal aspects of various components of the cable system. In particular, friction factors for laminar flow in the cable pipes with various configurations were determined using a finite element technique; the temperature distributions and heat transfer in splices were examined using a combined analytical numerical technique; the pressure drop and heat transfer characteristics of cable pipes in the transitional and turbulent flow regime were determined experimentally in a model study; and full-scale model experimental work was carried out to determine the fluid dynamic and thermal characteristics of entrance and exit chambers for the cooling oil. The second major area of activity, reported in this volume, ...
Electrical power is generated by steam turbines (steam being produced by coal, oil, gas or nuclear reactors), hydro units, gas turbines, internal combustion engines, jet engines, and pumped storage plants. Nuclear Power Plants generate only 15% of the total electrical power in the US. Nuclear Power Plants being cheaper to run are generally base loaded. The pumped-storage and gas turbine plants have ideal characteristics for peaking duty. In the pumping mode, pumped storage plants are used to provide additional system load and in the generating mode, they supply reactive power during peak load demands. Gas turbine plants have higher running costs, but are used as peaking units with a fast start capability. Fossil power plants need a minimum of 1 hour to stabilize expansion in the boiler and turbine generator. Due to a more competitive power supply market due to deregulation, most of the utilizes plan ...
1. This study analyzes the mechanisms involved in the responses to ouabain in cat cerebral and femoral arteries and characterizes the electrogenic Na+ pump present in these vessels. The latter was accomplished...Full Text Available
The dissociation of methylal is investigated using mass spectrometry, combined with a pyrolytic radical source and femtosecond pump probe experiments. Based on preliminary results two reaction paths of methylal dissociation are proposed and discussed. (author) 4 fig., 3 refs.
Object: To smoothly control automatic water supply for realizing stable operation of a nuclear reactor by providing a flow rate limiting signal selection circuit and a preferential circuit in a water supply control device for a nuclear reactor wherein the speed of a recirculation pump may be changed in two-steps. Structure: Opening angle signals for a water supply regulating valve are controlled by a nuclear reactor water level signal, a vapor flow rate signal and a supplied water flow rate signal through an adder and an adjuster in response to a predetermined water level setting signal. When the water in the reactor is maintained at a predetermined level, a selection circuit receives a water pump condition signal for selecting one of the signals from a supplied water rate limiting signal generator generating signals for indicating whether one or two water supply pumps are operated. A low value preferential circuit passes ...
Cyclophilins (Cyps), the intracellular receptors for Cyclosporine A (CsA), are responsible for peptidyl-prolyl cis-trans isomerisation and for chaperoning several membrane proteins. Those functions...Full Text Available
The F1F0 ATPase of Vibrio alginolyticus was cloned from a chromosomal lambda library. The unc operon, which contains the structural genes for the ATPase, was sequenced and shown to have a gene organization...Full Text Available
The merits of single stage absorption heat pumps coupled to simple distillation for effluent treatment are discussed. An experimental integrated absorption heat pump effluent purification system (IAHPEPS) was built and operated with water-lithium bromide as a working mixture. This unit has been used to raise the temperature and hence, the vapour pressure of the impure water contained in one vessel, to the point where pure water vapour will distil from impure effluent solution (tap water or brine) and condense in a second vessel used to collect pure water. Pure effluent production rates of between 0.5 and 4.3 kg h{sup -1} were obtained. The actual coefficient of performance (COP{sub A}) and the heat pump effectiveness varied from 1.1 to 1.4 and 0.58 to 0.72, respectively. The results from the small scale systems indicate the likely results from industrial scale units which could be operated with low quality heat such as ...
The expression of tripartite multidrug efflux pumps such as MexA-MexB-OprM in Pseudomonas aeruginosa contributes to intrinsic resistance to a wide variety of antimicrobials, including...Full Text Available
...limited to, emission control devices, pumps, filters, muck cookers, stills, solvent tanks, solvent containers, water separators...facility that meets the conditions of § 63.320(g). Muck cooker means a device for heating perchloroethylene-laden...
This analysis defines and evaluates the surface water supply system from the existing J-13 well to the North Portal. This system includes the pipe running from J-13 to a proposed Booster Pump Station at the intersection of H Road and the North Portal access road. Contained herein is an analysis of the proposed Booster Pump Station with a brief description of the system that could be installed to the South Portal and the optional shaft. The tanks that supply the water to the North Portal are sized, and the supply system to the North Portal facilities and up to Topopah Spring North Ramp is defined.
Laser optical pumping can be used to produce polarized alkali atom beams or polarized alkali vapor targets. Polarized alkali atom beams can be converted into polarized alkali ion beams, and polarized alkali vapor targets can be used to produce polarized H/sup -/ or /sup 3/He/sup -/ ion beams. In this paper the authors discuss how the polarized alkali atom beams and polarized alkali vapor targets are used to produce polarized ion beams with emphasis on the production of polarized negative ion beams.
This report illustrates how, thanks to the development of a new algorithm for the probabilistic evaluation in a given period (e.g. one week) of the operating costs and risk indices (reliability) of a generation system with energy-constrained units, it has been possible to significantly improve the WAT program, used for many years by ENEL for generation expansion planning studies. In particular, it describes how the annual simulation of the system operation is accomplished, so as to calculate the mean expected values of the yearly operating costs (fuel) and the risk indices, at the same time optimizing the use of hydro resources and pumped-storage plants. (author).
Excitation of the HF electric field in the local plasma resonance region (LPRR) of inhomogeneous plasma by pumping electric field or modulated electron beam results to appearance of the ponderomotive force that presses plasma out of this region. Density cavity is formed in the LPRR due to this field. Further dynamics in this region depends on the plasma properties. For plasma with hot electrons ion-acoustic pulses run away from the cavity. at the local density maximum the new peak of electric field is excited. It results to the formation of new density cavity, etc. For isothermal plasma the density jump is formed.
This letter describes the first lasing experiment of the heterostructure semiconductor Raman laser with lateral confinement of both the Stokes and pump fields. It has a GaP Raman active layer with thickness of 10 ..mu..m and Al/sub 0.1/Ga/sub 0.9/P cladding layers. The stripe of the active layer has been fabricated by a plasma etching technique. Steps should be taken to realize the semiconductor Raman laser pumped by an injection laser, applicable to wideband optical communication.
Why pay for energy when there`s a free stockpile of it right under your feet? With the help of a geothermal heat pump system, one can extract that energy from the ground and put it to good use, lowering heating and cooling costs. From private homes to public schools and fast-food restaurants, an increasing number of establishments are turning to geothermal heat pump systems for space conditioning. Experts say 1998 is already proving to be the best year yet for the technology, and they foresee an even more promising future. Some examples of geothermal energy use are given.
A surface may provide a useful pumping action when able to retain adsorbed gas molecules for the duration of a given experiment. To fulfil this condition at room temperature, strong binding forces, as those resulting from chemical reactions, are required. Materials able to react with gases to form stable chemical compounds are called getters. The two main families of getters (evaporable and non-evaporable, or NEG) are presented and discussed. Special emphasis is placed on the NEG strips currently used for the vacuum systems of particle accelerators, and on the newly developed NEG thin-film coatings, in view of their possible future applications.
In an electromagnetic pump of the present invention for use in circulation of coolants in an LMFBR type reactor, the outer circumference of coil conductors is covered by an insulator retaining cover, and powdery or granular insulator is filled between the coil conductors and the insulator retaining cover. Upon reaching high temperature, elongation of the coil conductors by heat expansion is absorbed by movement of the particles of the powdery insulator thereby preventing excess stresses from exerting on the coil insulator constituted with the insulator retaining cover and the powdery or granular insulator and preventing generation of crackings on the coil insulator. Thus, plant stability is improved. (N.H.).
In clinical applications, it is very important to accurately determine the range of a proton beam in a patient. Recently, a prototype prompt-gamma scanning system, called a prompt-gamma scanner (PGS), has been constructed at Hanyang University in Korea with the collaboration of the Korean national cancer center (NCC), based on a series of Monte Carlo simulations. The PGS system is composed of a prompt-gamma collimator, a CsI(Tl) scintillation detector, a multi-channel analyzer (MCA), a precision movement system, and an integrated readout system. The prompt-gamma collimator is designed to effectively shield high-energy neutrons from the proton beam passage and subsequent capture gammas. The PGS system can be used to scan the distribution of the prompt gammas in the patient from the proton beam passage. The distribution of the prompt gammas can then be used to determine the proton beam range or the distal ...
The results of investigation into a new series of Z-even nuclei - precursors of delayed protons (PDP) -"6"5Ge, "8"9Se, "9"3Kr, "8"1Zr, and "8"5Mo are presented. PDP were obtained by irradiation of targets in the following reactions: Zn(He, 2n) "6"5Ge, 22 MeV; "4"0Ca("3"2S, 2 pn) "1"9Se, 100 MeV; "6"0Ni ("1"60, 3 n), "7"3Kr, 75 MeV; "5"2Cr ("3"2S, 3n)"8"1Zr, 110 MeV; "5"6Fe("3"2S, 3n)"8"5Mo, 120 MeV. The targets (self-sustaining foils of thickness approximately 1.2 mg/cm"2) were placed at an angle of 15 deg to the direction of the ion beam. Upon irradiation targets were moved downwards into a measuring position. The spectra of protons, X and gamma-rays, and also the spectra of p - x, p-#gamma#, x - #gamma# coincidences accompanying the decay of "6"5Ge, "6"9Se,"7"3Kr and "8"1Zr, and "8"5Mo were measured. The measured half-lives are equal, to 31.5+-1.9, 27.3+-0.5, 28.5+-1.1, 6.3+-0.5, and 5.6 +-0.9 s respectively. The experimental spectra are ...
The acid-base behavior of the ground and excited states of Pt(qdt){sub 2}{sup 2{minus}} and Pt(phen)(qdt), where qdt=quinoxaline-2,3-dithiolate and phen = 1,10-phenanthroline, has been studied. The pH-dependent changes in the charge-transfer absorption and emission spectra for both complexes are attributed to protonation of the quinoxalinedithiolate ligand at the imine nitrogen. For Pt(qdt){sub 2}{sup 2{minus}}, single protonation leads to a large red shift (2582 cm{sup {minus}1}) of the low-energy charge-transfer-to-dithiolate absorption band and the emergence of a new red-shifted emission feature at 728 nm. In solutions of pH below 6, a second protonation takes place at the other qdt ligand, yielding Pt-(Hqdt){sub 2}. This neutral complex has been isolated and characterized by {sup 1}H NMR spectroscopy and elemental analyses. The ground-state basicity constants of the two protonation steps have been ...
A geothermal heat pump-assisted heating system is introduced into Changchun City and a survey is conducted to determine if the system may be popularized in this extremely cold region located in the northeastern part of China. In concrete terms, the hot water that circulates through the office building of Changchun Ground Heat Development Co., Ltd., is switched to hot water prepared by a geothermal heat pump. The test continued from December 2000 to March 2001. It is then concluded that heating by geothermal heat pumps will be fully serviceable to Changchun City. Implemented are (1) the shift from the coal fired boiler system to a geothermal heat pump system comprising 16 subterranean heat exchangers for the heating of the office building which is approximately 1000 m{sup 2} large, (2) long-term monitoring of the operating conditions, (3) measurement of subterranean heat exchanger thermal conductivity ...
Using a noneikonal expression for the two-body scattering amplitude, consistent with the proton-nucleon scattering data, the cross-section of the 1.04 GeV-proton elastic scattering on {sup 40}Ca is calculated by the Glauber-Sitenko theoretical scheme in the framework of the coherent density fluctuation model (CDFM) as well as of the independent-particle model (IPM). It is shown that the use of the noneikonal amplitude in the CDFM calculations improves the agreement with the experimental data especially at larger scattering angles in contrast to the case of the independent-particle model. To that end a decisive role play the zero-motion flucton correlations taken into account in the CDFM. (orig.).
Using a noneikonal expression for the two-body scattering amplitude, consistent with the proton-nucleon scattering data, the cross-section of the 1.04 GeV-proton elastic scattering on "4"0Ca is calculated by the Glauber-Sitenko theoretical scheme in the framework of the coherent density fluctuation model (CDFM) as well as of the independent-particle model (IPM). It is shown that the use of the noneikonal amplitude in the CDFM calculations improves the agreement with the experimental data especially at larger scattering angles in contrast to the case of the independent-particle model. To that end a decisive role play the zero-motion flucton correlations taken into account in the CDFM. (orig.).
This report covers the progress made on the title project for the project period. Four major areas of inquiry are being pursued. Advanced solid state NMR methods are being developed to assay the distribution of the various important functional groups that determine the reactivity of coals. Special attention is being paid to methods that are compatible with the very high magic angle sample spinning rates needed for operation at the high magnetic field strengths available today. Polarization inversion methods utilizing the difference in heat capacities of small groups of spins are particularly promising. Methods combining proton-proton spin diffusion with [sup 13]C CPMAS readout are being developed to determine the connectivity of functional groups in coals in a high sensitivity relay type of experiment. Additional work is aimed at delineating the role of methyl group rotation in the proton NMR relaxation behavior of coals.
In a forthcoming paper we describe a new approach to rapidity gap survival (RGS) in the production of high-mass systems (H = dijet, Higgs, etc.) in exclusive double-gap diffractive pp scattering, pp -> p + H + p. It is based on the idea that hard and soft interactions are approximately independent (QCD factorization), and allows us to calculate the RGS probability in a model-independent way in terms of the gluon generalized parton distributions (GPDs) in the colliding protons and the pp elastic scattering amplitude. Here we focus on the transverse momentum dependence of the cross section. By measuring the ''diffraction pattern'', one can perform detailed tests of the interplay of hard and soft interactions, and even extract information about the gluon GPD in the proton from the data.
Elastic and inelastic proton scattering has been measured in inverse kinematics on the unstable nucleus {sup 40}S. A phenomenological DWBA analysis yields a quadrupole deformation parameter {beta}{sub 2} = 0.35 {+-} 0.05 for the 2{sup +}{sub 1} state. Consistent phenomenological and microscopic proton scattering analyses have been applied to all even-even Sulfur isotopes from A = 32 to A = 40. The microscopic analysis used microscopic collective model densities and a modified Jeukenne-Lejeune-Mahaux effective interaction. This analysis suggests the presence of a neutron skin in the heavy sulfur isotopes. The analysis is consistent with normalization values for {lambda}{sub {upsilon}} and {lambda}{sub {omega}} of 0.95 for both the real and imaginary parts of the JLM potential. (author)
Polarization measurements are allowing the electric to magnetic form factor ratio of the proton to be determined with unprecedented precision. Recent results indicate that there is a large deviation from unity in the proton form factor ratio around Q{sup 2}{approx_equal}0.35 GeV{sup 2}. Furthermore, the deviation from unity is attributed to a deviation of the electric form factor from standard fits and calculations. A new, partially completed, experiment will significantly improve the existing data and will determine the presence, if any, of a narrow structure in the form factor ratio. The new measurement, combined with the expected high precision cross section measurements, will allow the extraction of individual form factors with unprecedented accuracy at low Q{sup 2}.
Experimental measurements were made of the production cross sections and energy distributions of gamma rays emitted when the stable targets /sup 88/Sr, /sup 89/Y and /sup 90/Zr are exposed to protons in the energy range 3 to 8 MeV. The data are being analyzed using a recent version of the Uhl statistical model code. One conclusion is that while the gamma-ray strength functions employed reproduce the proton capture cross sections, they do not achieve the same degree of hardness observed in the measured spectra. To do so, their lower energy regions must be modified; such changes, however, do not affect the capture cross sections. 7 references.
The proton and neutron densities, root-mean-square (rms) radii of proton density and neutron density, and neutron skin thickness of "4"-"1"0He, "6"-"1"1Li, and "7"-"1"2Be isotopes are calculated using Skyrme-Hartree-Fock method with SLy4, SLy5, SLy6, and SLy7 force parameters. The evaluated results are compared with experimental data. Also, the results of halo nuclei ("6","8He, "1"1Li, and "1"1Be) are compared with the results of other isotopes for selected nuclei having the same neutron configuration.
The article is devoted to results of fine time structure of particle losses in Tevatron with use of fast beam loss monitors (BLM) based on PIN-diodes. An ultimate goal of the new BLMs is to distinguish losses of protons and antiprotons from neighbor bunches with 132 ns bunch spacing in the Tevatron collider upgrade. The devices studied fit well to the goal as they can recognize even seven times closer - 18.9 ns - spaced bunches` losses in the Tevatron fixed target operation regime. We have measured main characteristics of the BLM as well as studied the proton losses over 10 decades of time scale - from dozen of minutes to dozen of nanoseconds. Power spectral density of the losses is compared with spectra of the proton beam motion.
A sulfonated fluoroalkyl graft polymer (FGP) membrane was prepared as a polymer electrolyte. First, the FGP membrane was grafted with styrene under UV irradiation. The grafted FGP was then sulfonated to functionalize it for proton conductivity. The grafting degree of the membrane increased with increasing grafting time during UV irradiation. The proton conductivity of the membrane increased with increasing grafting degree. The swelling ratio was independent of the grafting time, however, the water uptake increased with increasing grafting degree. Based on these results, it was found that the UV-initiated styrene grafting occurred along the membrane thickness direction. Moreover, the membrane was embedded within the glass fibers of the composite. This composite electrolytic membrane had 1.15 times the proton conductivity of a Nafion 117 membrane.
High temperature proton conductor (HTPC) oxides are attracting extensive attention as electrolyte materials alternative to oxygen-ion conductors for use in solid oxide fuel cells (SOFCs) operating at intermediate temperatures (400-700 "0C). The need to lower the operating temperature is dictated by cost reduction for SOFC pervasive use. The major stake for the deployment of this technology is the availability of electrodes able to limit polarization losses at the reduced operation temperature. This review aims to comprehensively describe the state-of-the-art anode and cathode materials that have so far been tested with HTPC oxide electrolytes, offering guidelines and possible strategies to speed up the development of protonic SOFCs. (topical review)
We compute the corrections from two-photon and {gamma}-Z exchange in parity-violating elastic electron-proton scattering, used to extract the strange form factors of the proton. We use a hadronic formalism that successfully reconciled the earlier discrepancy in the proton's electron to magnetic form factor ratio, suitably extended to the weak sector. Implementing realistic electroweak form factors, we find effects of the order 2%-3% at Q{sup 2} < or approx. 0.1 GeV{sup 2}, which are largest at backward angles and have a strong Q{sup 2} dependence at low Q{sup 2}. Two-boson contributions to the weak axial current are found to be enhanced at low Q{sup 2} and for forward angles. We provide corrections at kinematics relevant for recent and upcoming parity-violating experiments.
A 20-MeV proton accelerator is developed by Proton Engineering Frontier Project (PEFP) at Korea Atomic Energy Research Institute (KAERI). The 20MeV accelerator consists of 50keV proton injector, 3MeV RFQ (Radio frequency Quadrupole), 20MeV DTL (Drift Tube Linac) and 20MeV beam line. The beam profile was measured at the end of the 20MeV beam line with wire scanner. Moreover the beam emittance was calculated from the quad scan method using beam line quadrupole magnets. In this paper, the beam profile measurement results are presented and the emittance measurement from the quad scan method is discussed
as for direct energy conversion in specialized direct electrical energy conversion plants. Figure 1. An energetic (~163KeV) proton and a 11boron nucleus fuse ...
SUMMARYIn voltage-gated sodium, potassium, and calcium channels the functions of ion conduction and voltage sensing are performed by two distinct structural units: the pore domain...Full Text Available
Electrophysiological events are of central importance during the phagocyte respiratory burst, because NADPH oxidase is electrogenic and voltage sensitive. We investigated the recent suggestion that...Full Text Available
Generation of reactive oxygen species by the NADPH oxidase complex is an important bactericidal weapon of phagocytes. Phorbol myristate acetate (PMA) is a potent agonist for this “respiratory...Full Text Available
When oxygen is limiting, animals can ferment glucose via several metabolic pathways varying in energetic efficiency and leading to various end products (such as lactate, succinate, or propionate). Because the pH dependence of H/sup +/ production by fermentation is opposite to that by hydrolysis of adenosine triphosphate formed in the fermentation, the total number of moles of protons generated is always two per mole of fermentable substrate. However, two and three times more adenosine triphosphate can be turned over per mole of protons produced in succinate and propionate fermentations, respectively, than in lactate fermentation. At its limit, this advantage would achieve the same balance between H/sup +/ production and H/sup +/ consumption during ATP cycling that is observed in aerobic metabolism, a situation observed in certain alcohol fermentations. Since proton balance during anaerobiosis is clearly adaptable, we ...
When any new accelerator or storage ring is built that advances the state of the art, the diagnostic system becomes extremely important in tuning the facility to full specification. This paper will discuss the various diagnostic devices planned or under construction for the PSR and their connection into the control system.
Lithium ammonium sulfate (LAS) undergoes a phase transition at Tsub(c1) = 459.5deg K from a paraelectric phase (phase 1) to a ferroelectric phase (phase II) and again at Tsub(c2) = 283deg K to a polar ferroelastic phase (phase III). Proton spin lattice relaxation investigations in the temperature range 480-77deg K at 10 MHz show discontinuous changes in Tsub(1) at the transition temperatures, indicating first order phase transitions. The absence of the slow motion region (#omega#sub(not)tausub(not)>>1) shows that the ammonium ions are reorienting fast enough to keep the resonance absorption line narrow down to liquid nitrogen temperatures. The possibility of a second minimum and a low activation energy, Esub(a) = 2.659 kcal/mole, in phase III suggest the possibility of tunnelling of the protons at low temperatures. The nature of the transitions have been discussed in the light of the available literature. The unusually high activation ...
The ratio of the proton's electric to magnetic form factor, G{sub E}/G{sub M}, can be extracted in elastic electron-proton scattering by measuring cross sections, beam-target asymmetry, or recoil polarization. Separate determinations of G{sub E}/G{sub M} by cross sections and recoil polarization observables disagree for Q{sup 2}>1 (GeV/c){sup 2}. Measurement by a third technique might uncover an unknown systematic error in either of the previous measurements. The beam-target asymmetry has been measured for elastic electron-proton scattering at Q{sup 2} = 1.51 (GeV/c){sup 2} for target spin orientation aligned perpendicular to the beam momentum direction. This is the largest Q{sup 2} at which G{sub E}/G{sub M} has been determined by a beam-target asymmetry experiment. The result, {mu}G{sub E}/G{sub M}=0.884{+-}0.027{+-}0.029, is compared to previous world data.
Amphiphilic block copolymers are synthesized by sulfonation of poly(styrene-b-methyl methacrylate) (PS-b-PMMA) using acetyl sulfate, and are blended with poly(vinylidene fluoride) (PVDF) to prepare a new proton exchange membrane, in which PMMA is miscible with PVDF. The morphology and the transport properties of the membranes are investigated as functions of the degree of sulfonation as well as the blend ratio. Notable transition of phase-separated morphology is observed as the PVDF content of the blend is increased. Both the proton conductivity and the ion-exchange capacity (IEC) of the membrane increase with increasing the degree of sulfonation of PS-b-PMMA, and they are also enhanced as the phase-separated domains of blend membrane are well-ordered. Unlike the Nafion membrane, the proton conductivity of the blend membrane increases up to 90 C, indicating the blend membrane shows better thermal stability than the Nafion ...
A red light-induced, far red reversible stimulation of proton efflux from apical segments of etiolated Avena sativa L. cv. Victory coleoptiles was observed. The acidification...Full Text Available
The quantitative estimation of various trace element concentrations in medicinal plants is necessary for determining their effectiveness in treating various diseases and for understanding their pharmacological action. Elemental concentrations of some selected medicinal plants of north east India was measured by proton induced X-ray emission (PIXE) and proton induced {gamma}-ray emission (PIGE) techniques. PIXE measurements were carried out using 2.4 MeV collimated protons from the 3 MV tandetron accelerator of NCCCM, Hyderabad (India) while the PIGE measurements were carried out using 3 MeV protons from the same accelerator in the same laboratory. Accuracy and precision of the techniques were assured by analyzing certified reference materials in the same experimental conditions. Various elements of biological importance in man's metabolism were found to be present in varying concentrations in ...
It has been discovered that iron(III) chloride complexes supported on activated charcoal oxidize phosphine under normal conditions. The process accelerates as the concentration of the chloride ions and the proton acid increases.
Probabilities of flucton production have been calculated for the 1p-shell nuclei and its modification by the Yastrov method. The results obtained are in a qualitative agreement with the data resulting from the analysis of experiment in an assumption of a flucton mechanism of proton-nuclear inclusive reactions with the production of cumulative particles.
BackgroundTo evaluate the performance of three different advanced treatment techniques on a group of complex paediatric cancer cases.MethodsCT...Full Text Available
W. Wayne Scott. ABSTRClCT. Primary proton and secondary particle doses (both .... W. Wayne Scott and R. G. Alsmiller, Jr., Comparisons of Results Ob- ...
First comprehensive data on the evolution of nucleon resonance photocouplings with photon virtuality Q{sup 2} are presented for excited proton states in the mass range from 1.4 to 2.0 GeV.
A new gadolinium chelating NIR fluorescent molecular probe increases T1 relaxivity of water protons, facilitating combined optical and magnetic resonance imaging.
The LSND (Liquid Scintillator Neutrino Detector) experiment will be performed at LAMPF in the next several years. The main goal of the experiment is to search for {nu}{sub {mu}}-{nu}{sub e} oscillations with high sensitivity; however, an increasingly important by-product of this search is to measure {nu}p {yields} {nu}p elastic scattering and determine the strange quark contribution, {Delta}s, to the spin of the proton. With the 800-MeV proton energy of LAMPF, neutrinos are produced from pion decay-in-flight with an average energy of about 150 MeV. This energy is sufficiently high so that the {nu}p {yields} {nu}p cross section is large and is sufficiently low so that the low Q{sup 2} approximation (Q{sup 2} {much lt} m{sub p}{sup 2}) is valid and the cross section can be expressed in a simple form dependent upon {Delta}s as the only unknown. LAMPF with its 1-mA proton intensity is, therefore, an ideal accelerator to perform ...
The weak interaction between neutrons and protons has never been resolved experimentally. In analogy with the strong NN interaction, the weak NN interaction at low energy can be parametrized in terms of a meson exchange model with parity violating meson-nucleon couplings. Unlike the measured proton-proton weak interaction, the neutron-proton weak interaction is sensitive to the weak pion-nucleon coupling constant H{sub {pi}}{sup 1}. This coupling, which is responsible for the longest-ranged part of the weak NN interaction and is therefore an essential part of any description of weak interactions in nuclei, remains undetermined despite many years of effort. A measurement of the gamma ray directional asymmetry A{sub {gamma}} in the capture of polarized neutrons by parahydrogen has been proposed at Los Alamos National Laboratory. The goal of this experiment is to determine A{sub {gamma}} with a relative standard uncertainty of ...
The mechanism of metabolic energy production by malolactic fermentation in Lactococcus lactis has been investigated. In the presence of L-malate, a proton motive force composed of a membrane potential...Full Text Available
Lactobacillus buchneri ST2A vigorously decarboxylates histidine to the biogenic amine histamine, which is excreted into the medium. Cells grown in the presence of histidine generate both a transmembrane...Full Text Available
Thermophilic propionate-oxidizing, proton-reducing bacteria were enriched from the granular methanogenic sludge of a bench-scale upflow anaerobic sludge bed reactor operated at 55°C with a mixture...Full Text Available
We report a detailed augmented-plane-wave energy-band study and wave-function analysis of stoichiometric PdH which shows that, even though the Fermi surface of PdH is qualitatively similar to that of silver, the simple ''proton model'' is not valid. Instead, the screening of the proton in PdH is found to be larger than in an isolated H atom due, in part, to the formation of a H-Pd bonding band below the bottom of the d-band complex. This result, which is in qualitative agreement with Switendick's earlier calculation, is confirmed by ultraviolet photoemission experiments. A partial density-of-states (DOS) analysis in the energy range spanned by the six valence and conduction bands reveals the quantitative details of the bonding mechanism between the Pd and H constituents. At the Fermi energy, the high Pd d to H s DOS ratio approx. 10.3 is found to be far higher than expected in silver, despite the fact that the Fermi-surface geometry is similar. ...
... ions. MATERIALS AND METHODS Cell Culture Culture of NT2/D1 cells was carried out as described previously (18, 19). NT2 cells were plated at a density of 2. ... ...
The system of the early forecast of radiation hazardous fluxes of solar cosmic rays in space on the basis of the real time neutron monitors data obtained by the NMDB (Neutron Monitor Data Base) network is created. The forecast system is based on a short cut technique of definition of a spectrum of solar protons from the data of the limited number of neutron monitor stations and with a simplified procedure of accounts. It is shown that the results of computations of solar proton spectra with the short-cut technique little differ from spectra obtained with a complete technique at energies less than 5 GeV. Thus the good agreement between derived from the neutron monitor data intensities of solar protons in an energy range of hundreds MeV with the data of direct measurements of solar protons at GOES-11 spacecraft is observed. The maximum of increase on neutron monitors outstrips on several hours (2-10) an ...
In voltage-gated Na+, K+, and Ca2+ channels, four voltage-sensor domains operate on a central pore domain in response to membrane voltage. In contrast, the voltage-gated...Full Text Available
Differential cross sections of elastic scattering of 104 MeV #alpha# particles from "2"0"4,"2"0"6,"2"0"8Pb have been measured with high angular accuracy. The analyses are based on a folding model treating the proton and neutron distributions independently. The proton distributions were taken from precise electron scattering results. The neutron distributions were parametrized by a modified Gaussian the parametrers of which were varied in order to fit the experimental cross sections. The resulting rms radii of the neutron distributions exceed the rms radii of the proton distributions by #DELTA#r=0.22 +- 0.09 fm for "2"0"4Pb, #DELTA#r = 0.19 +- 0.09 fm for "2"0"6Pb, and #DELTA#r = 0.30 +- 0.07 fm for "2"0"8Pb.
Correlations are studied between the power density of Alfv\\'en-cyclotron waves (having frequencies between 0.02 and 2 Hz) and the ratio of the perpendicular and parallel temperature of the protons. The wave power spectrum is evaluated from high-resolution 3D magnetic field vector components, and the ion temperatures are derived from the velocity distribution functions as measured in fast solar wind during the Helios-2 primary mission at radial distances from the Sun between 0.3 AU and 0.9 AU. From our statistical analysis, we obtain a striking correlation between the increases in the proton temperature ratio and enhancements in the wave power spectrum. Near the Sun the transverse part of the wave power is often found to be by more than an order of magnitude higher than its longitudinal counterpart. Also the measured ion temperature anisotropy appears to be limited by the theoretical threshold value for the ion-cyclotron instability. This ...
Compact dielectric wall (DWA) accelerator technology is being developed at the Lawrence Livermore National Laboratory. The DWA accelerator uses fast switched high voltage transmission lines to generate pulsed electric fields on the inside of a high gradient insulating (HGI) acceleration tube. Its high electric field gradients are achieved by the use of alternating insulators and conductors and short pulse times. The DWA concept can be applied to accelerate charge particle beams with any charge to mass ratio and energy. Based on the DWA system, a novel compact proton therapy accelerator is being developed. This proton therapy system will produce individual pulses that can be varied in intensity, energy and spot width. The system will be capable of being sited in a conventional linac vault and provide intensity modulated rotational therapy. The status of the developmental new technologies that make the compact system possible will be reviewed. ...
The membrane properties of isolated cultured microglia have been extensively studied but it is important to understand their properties in situ, where they protect the brain against...Full Text Available
Biosorption of the heavy metal ion Cd{sup 2+} by protonated nonliving brown alga Sargassum fluitans biomass was accompanied by the release of hydrogen protons from the biomass. The uptake of cadmium and the release of proton matched each other throughout the biosorption process. The end-point titration methodology was used to maintain the constant pH 4.0 for developing the dynamic sorption rate. The sorption isotherm could be well represented by the Langmuir sorption model. A mass transfer model assuming the intraparticle diffusion in a one-dimensional thin plate as a controlling step was developed to describe the overall biosorption rate of cadmium ions in flat seaweed biomass particles. The overall biosorption mathematical model equations were solved numerically yielding the effective diffusion coefficient D{sub e} about 3.5 {times} 10{sup {minus}6} cm{sup 2}/s. This value matches that obtained for the desorption process ...
To calibrate channels A1 to A4 for particles with Z >= 1, tests were done on the IBIS accelerator at AERE, Harwell, which gave protons up to 3 MeV. ...
A technique of low-field pulsed proton nuclear magnetic resonance (NMR) spin relaxation is described for assessment of age-related structural changes (dentin and pulp) of human teeth in...Full Text Available
The 1.04 GeV-proton elastic scattering from /sup 40/Ca is studied in the framework of the coherent density fluctuation model (CDFM). The calculations are carried out in the Glauber theoretical scheme with three different charge densities. It is shown that: i) the account of the flucton correlations leads to results considerably different from those obtained in the independent particle Glauber approach (IPGA); ii) in contrast to the case of IPGA the use of a more realistic density improves the agreement of CDPM-results with the experimental data.
The 1.04 GeV-proton elastic scattering from "4"0Ca is studied in the framework of the coherent density fluctuation model (CDFM). The calculations are carried out in the Glauber theoretical scheme with three different charge densities. It is shown that: i) the account of the flucton correlations leads to results considerably different from those obtained in the independent particle Glauber approach (IPGA); ii) in contrast to the case of IPGA the use of a more realistic density improves the agreement of CDPM-results with the experimental data. (orig.).
We studied two-photon exchange for elastic electron-proton scattering at low Q{sup 2}. Compact approximate formulas for the amplitudes were obtained. Numerical calculations were done for Q{sup 2}{<=}0.1 GeV{sup 2} with several realistic form factor parametrizations, yielding similar results. They indicate that the corrections to the magnetic form factor can visibly affect the cross-section and proton radii. For low-Q{sup 2} electron-neutron scattering two-photon exchange corrections were shown to be negligibly small00.
Japan Atomic Energy Research Institute (JAERI) and the High Energy Accelerator Research Organization (KEK) are promoting the joint project integrating both the Neutron Science Project (NSP) of JAERI and the Japan Hadron Facility Project (JHF) of KEK for comprehensive studies on basic science and technology using high-intensity proton accelerator. This document describes the joint project prepared by the Joint Project Team of JAERI and KEK to construct accelerators and research facilities necessary both for the NSP and the JHF at the site of JAERI Tokai Establishment. It was originally written in English and translated into Japanese with some corrections. (author)
Unique measurement of the proton structure function F2 in a wide two-dimensional region of x and Q**2 has been reported. The accessible kinematics covers entire resonance region up to W=2.5 GeV in the Q**2 interval from 0.1 to 4.5 GeV**2. Obtained data allowed for the first time an evaluation of moments of the structure function F2 directly from experimental data as well as an intensive study of the Bloom-Gilman duality phenomenon.
The conceptual design for a cyclotron that could possibly deliver a 10 MW proton beam, presented at the previous ADTT conference, is discussed in comparison with the operational experience gained with 0.9 MW beam power in the upgraded cyclotron facility at PSI that has reached the design goal of 1.5 mA at 590 MeV in 1995. Some critical aspects of the design are e.g. RF power and beam loading, beam loss and activation, space charge effects and bunching. 12 refs., 2 figs., 1 tab.
Surface doping of conjugated polymers is realized by depositing a thin layer of graphene oxide (GO) on top of the polymers. The high proton density and the unique 2D structure of GO facilitate the protonic surface doping of conjugated polymers to achieve high conductivities. This finding represents a new strategy for improving charge transport across the metal/conjugated polymer interface to achieve much improved performance in organic solar cells. (Copyright copyright 2011 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim)
Sol-gel chemistry has a great many potential applications in the preparation of unique electrochemical materials, from non-equilibrium transition metal oxides which may be of use as high energy density electrodes, to high-surface area mixed oxides which may possess high proton conductivity, to novel composite structures consisting of inorganic gels in combination with organic, electronic, and ionic conductors. This paper reviews prior work on proton conduction in gel systems and presents recent work regarding electrode materials prepared by sol-gel methods and inorganic-organic materials.
A method is proposed for the quantitative isolation of radiothallium in gas form from proton-bombarded lead of mass up to 20 g. The molten lead is kept at about 800 K in hydrofluoric-acid vapor (HF/H/sub 2/O approx. = 1) at a reduced pressure (less than or equal to4 Pa). We used 99.9% lead with the U-240 cyclotron at the Nuclear Research Institute, Academy of Sciences of the Ukrainian SSR, or the phasotron at the Join Nuclear Research Institute, which gave protons at 65 and 680 MeV correspondingly.
A method is proposed for the quantitative isolation of radiothallium in gas form from proton-bombarded lead of mass up to 20 g. The molten lead is kept at about 800 K in hydrofluoric-acid vapor (HF/H_2O #approx =# 1) at a reduced pressure (#<=#4 Pa). We used 99.9% lead with the U-240 cyclotron at the Nuclear Research Institute, Academy of Sciences of the Ukrainian SSR, or the phasotron at the Join Nuclear Research Institute, which gave protons at 65 and 680 MeV correspondingly.
The study of imported ceramics found in Beirut and suspected to belong to north Syrian products will provide key evidence for the roles in trade of the various postulated centers in northern Syria and northern Lebanon. It is proposed that a comprehensive range of likely north Syrian products imported to Beirut will be chemically analyzed by PIXE (proton induced X-ray emission) in order to characterize, compare and isolate the various regional production centers that supplied the city from the Persian to Byzantine periods. In this work, we were mainly focusing on the characterization of Amrit products, by using 3 MeV proton beam and Al funny filter, as X-ray absorber.
The RSS collaboration has measured the spin structure functions of the proton and the deuteron at Jefferson Lab using the Hall C HMS spectrometer, a polarized electron beam and a polarized solid target. The asymmetries A and A were measured in the region of the nucleon resonances (0.82 GeV < W < 1.98 GeV) at an average four momentum transfer of Q2 = 1.3 GeV2. The extracted spin structure functions and their kinematic dependence will make a significant contribution in the study of higher-twist effects and polarized duality tests. A description of the experiment and the latest findings of the analysis will be presented.
We analyse data on forward {eta} -meson photoproduction off a proton target and extract the {eta}{yields}{gamma}{gamma} decay width utilizing the Primakoff effect. The hadronic amplitude that enters into our analysis is strongly constrained because it is fixed from a global fit to available {gamma}p{yields}p{eta} data for differential cross-sections and polarizations. We compare our results with present information on the two-photon {eta} -decay from the literature. We provide predictions for future PrimEx experiments at Jefferson Laboratory in order to motivate further studies. (orig.)
Polarized antiprotons produced by spin filtering with an internal polarized gas target provide access to a wealth of single- and double-spin observables, thereby opening a window to physics uniquely accessible with the HESR at FAIR. This includes a first measurement of the transversity distribution of the valence quarks in the proton, and a first measurement of the moduli and the relative phase of the time-like electric and magnetic form factors G{sub E,M} of the proton. In polarized and unpolarized pp-bar elastic scattering open questions like the contribution from the odd charge-symmetry Landshoff-mechanism at large |t| and spin-effects in the extraction of the forward scattering amplitude at low |t| can be addressed.
The proton momentum distributions of (39)K,(40)Ca and (48)Ca are calculated from the model-independent charge distributions obtained from analyses of electron elastic scattering and muonic atoms, and also from the charge distributions calculated from the single-particle potential method in the framework of the flucton model. The sensitivities of the momentum distribution to different regions of the charge distribution are determined. The analysis is extended to the neutron distributions using the single-particle potential method, and the differences between the proton and neutron momentum distributions are examined. The resulting momentum distribution in the case of (40)Ca is used for analyzing the quasielastic electron scattering.
A ''coherent flucton'' nuclear model is proposed which provides for new possibilities for particle scattering studies on nuclei. It is based on the data of nuclear matter density distribution and is used for calculating the ground state energy of Fermi system terminals. The ''coherent flucton'' model is applied to the distribution of 1 GeV protons on "2"8Si, "3"2S, "4"0Ca, "4"8Ca, "5"8Ni, "2"0"8Pb nuclei. The calculations by the model agree well with experimental data.
Neutron spectra measured in the FFTF In-Reactor Thimble (IRT) by proton recoil proportional counters, proton recoil emulsions, and passive dosimeters have been evaluated and compared with each other and with three-dimensionl diffusion theory calculated spectra for the purpose of validating the passive dosimeter spectrum adjustment technique. The least squares data adjustment code, FERRET, was used to combine measured reaction rates, calculated spectra, and dosimeter cross sections, resulting in adjusted spectra and cross sections with uncertainties and correlations that properly account for uncertainties and correlations on the input parameters.
First measurements of inclusive Z production cross sections in muon and electron decay channels at 7 TeV are presented for proton-proton collisions in the Compact Muon Solenoid (CMS) detector at the Large Hadron Collider (LHC). The comparison of the kinematic quantities as well as the studies of selection efficiencies demonstrate a good agreement between simulated events and current data. The measured inclusive cross section for Z($\\gamma^{*}$) production agrees with NNLO QCD cross section calculations and current parton distribution functions.
The damage induced by low-temperature proton irradiation in amorphous Pd/sub 80/Si/sub 20/ prepared by ion implantation is studied via electrical resistivity measurements. Our experimental results concerning the initial damage rate and the resistivity saturation are compared to the results obtained for electron and high energy /sup 16/O irradiation of amorphous Pd/sub 80/Si/sub 20/ quenched from the melt. The resistivity curve is analyzed in terms of irradiation-induced point defects.
The L-subshell and total M-shell X-ray production cross sections of Ta, W, Pt, Au, Pb and Bi have been measured by protons of energy between 0.7 and 2.4 MeV. The obtained results for X-ray production cross sections have been compared with the existing experimental data, prediction of the ECPSSR theory and also with fitted empirical cross sections of Strivay and Weber.
We present recent results obtained in the Toulouse's group that deal with proton to base and nucleoside interactions. We stress the weakness of the sugar part in the nucleoside, i.e. the uridine molecule under scrutiny. Since some parts of the fragmentation spectrum correspond to the fragmentation of a 'pure' uracil molecule, i.e. the RNA base, an 'additivity rule' seems to prevail for the nucleoside, something that still has to be confirmed. Moreover, some results that deal with the secondary electronic emission from uracil are also displayed.
We present results for a complete set of polarization observables for jet production in lepton proton collision, where the final state lepton is not observed. The calculations are carried out in collinear factorization at the level of Born diagrams. For all the observables we also provide numerical estimates for typical kinematics of a potential future Electron Ion Collider. On the basis of this numerical study, the prospects for the transverse single target spin asymmetry are particularly promising. This observable is given by a certain quark-gluon correlation function, which has a direct relation to the transverse momentum dependent Sivers parton distribution.
Atomic L- and M-shell ionization cross sections by protons have been calculated in the plane-wave Born approximation for /sub 79/Au and /sub 92/U with incident energy from 0.1 to 3 MeV with use of relativistic and nonrelativistic Hartree-Slater wave functions. These results are compared with those from the screened hydrogenic model to study the effects of relativity and wave functions. The relativistic and wave-function effects are found to operate in opposite directions. For M/sub 1,2,3/-subshell cross sections, severe cancellations occur between these two factors.
We calculate the electromagnetic form factors of a bound proton. The chiral quark-soliton model provides the quark and antiquark substructure of the proton, which is embedded in nuclear matter. This procedure yields significant modifications of the form factors in the nuclear environment. The sea quarks are almost completely unaffected, and serve to mitigate the valence quark effect. In particular, the ratio of the isoscalar electric to the isovector magnetic form factor decreases by 20% at Q{sup 2}=1 GeV{sup 2} at nuclear density, and we do not see a strong enhancement of the magnetic moment.
PEFP(Proton Engineering Frontier Project) is developing beamlines for various application fields by using the high current 100MeV proton linear accelerator. Beamlines were characterized and categorized by the beam energy, average currents, and irradiation conditions. Among these beamlines the TR104 is designed for the basic science and the research of the aerospace. Before the construction and installation of beamlines, we try to practice and prepare the detail process of installation by the precedent study of TR104 beamline in KAERI site. By this work installation process was checked and confirmed for the same condition of the PEFP site
Energy and angular double-differential cross-section (DDX) data of fragment production reactions by neutrons or protons are very scarce due to experimental difficulties of fragment detection. We adopted a Bragg curve spectrometer (BCS), which is a gridded-ionization chamber that can identify fragments on the basis of the Bragg peak value. We have been developing the BCS for neutron and proton-induced reactions applying the digital waveform analysis technique to obtain better ability of particle discrimination than the analog electronic circuit. (T. Tanaka)
In this work, the chemical transformations induced by 5 keV protons (10{sup 6} ion cm{sup -2}) at the surface of 0.4 {mu}m polyacrylonitrile and polymethacrylonitrile films are analysed by XPS and IRRAS. Spectroscopic changes in both the polymers are globally similar, the most significant feature being a lower relative concentration of nitrogen with respect to carbon closer to the surface. Quantitatively, this change is more marked in the case of polyacrylonitrile which suggests a direct relation with the hydrogen in {alpha} to the nitrile function.
Computational fluid dynamics(CFD) code FLUENT was used to simulate the thermal hydraulic processes occurring in conceptual design of the accelerator-driven subcritical reactor(ADSR) liquid lead target. The purpose of the analysis is to investigate the thermal hydraulic characteristics of liquid lead as ADSR target material with various target geometries and injection locations of proton beam. In the calculation analysis, the local temperature of the liquid lead target rises to the boiling temperature very rapidly. When the proton beam is injected from the bottom of the target system, the duration time to reach the boiling temperature is longer and the temperature distribution is flatter than other cases.
The expected interstellar antiproton spectrum arising from cosmic-ray interactions in the Galaxy is recalculated, and the modulation of both antiprotons and protons is calculated using a two-dimensional modulation model incorporating gradient and curvature drifts and a wavy current sheet as well as the usual diffusion, convection, and energy-loss effects. Significant differences in the antiproton/proton ratio for different solar magnetic field polarities are predicted as well as a 'low-energy' component for antiprotons below about 1 GeV. 28 refs.
The A dependence of cumulative pion production yield cross sections on the basis of the comparison of the data on relative pion yields on Be,C,Al,Ti,Mo and W nuclei at the 159 deg angle laboratory system for the incident proton energy E_0 from 25 to 62 GeV is considered. The regular A dependence on cumulative variable X is noted. The results are compared with the data at E_0< 10 GeV. A possible interpretation of the observed behaviour on the basis of the hypothesis of the flucton mechanism of the pion production in the cumulative region is discussed. 15 refs.; 4 figs.
As the last step of urinary acidification, the inner medullary collecting duct (IMCD) is thought to secrete protons into the tubular lumens by means of a H(+)-translocating adenosinetriphosphatase (H(+)-ATPase). However, recent studies have also shown the existence of Na(+)-H+ exchange activity in IMCD cells. Although the physiological function of the antiporter in IMCD cells is unknown, activation of Na(+)-H+ exchange in other cell-culture systems has been suggested to be closely associated with the process of cell growth. Thus presence of Na(+)-H+ exchange may relate to the growth phase of these cells. To examine intracellular pH (pHi) regulation in growing IMCD cells, we studied proton transport by Na(+)-dependent and Na(+)-independent mechanisms by microfluorimetry using the pHi-sensitive dye 2',7'-bis(carboxyethyl)-5,6-carboxyfluorescein acetoxymethyl ester (BCECF/AM). Actively growing cells, defined by (3H)thymidine ...
An outline of Manitoba Hydro's Earth Power program was presented. Details of the heat pump market in Manitoba were provided, including details of residential and commercial sales. Total residential heat pump sales amounted to 577 units in 2004, equivalent to over $11.2 million in sales. Commercial installations amounted to approximately $12.7 million. An outline of industry players was presented. The goals of Manitoba Hydro were outlined in relation to geothermal energy and the Power Smart program. Their objectives included increasing awareness of geothermal energy, making heat pumps more accessible, and improving industry infrastructure. Other objectives included educating the public about life-cycle cost implications, residential loans and commercial incentives. To date, the residential power loan has provided financing to over 300 Manitoba home owners for installations, with electrical savings of over 1.34 Gwh and ...
In recent years, several larger geothermal heat pump plants for offices or commercial areas have been designed and built in the central region of Germany, mainly in the Rhein-Main area. Systems with borehole heat exchangers (BHE; in the USA the term Vertical Loop is commonly used) as well as with shallow geothermal doublets (groundwater wells) are operational. New solutions had to be found to adapt the technology to certain site constraints, and innovative components such as thermally-enhanced grouting material have been used. This paper reviews the early development of Ground Source Heat Pumps (GSHP) for commercial buildings, gives details on a number of recent plants and discusses problems that arose during their realisation: UEG Wetzlar, a building with chemical laboratories and one of the first examples of direct cooling from BHE; DFS Langen (German Air Traffic Control Headquarters), with 154 BHE for heating and cooling, operating without ...
Norway is a member of Annex 29, 'Ground-Source Heat Pump Systems Overcoming Technical and Market Barriers' (2004-2006), organized under the umbrella of the International Energy Agency (IEA) and the IEA Heat Pump Programme (HPP). The 7 participating countries are Austria (Operating Agent), Canada, Japan, Norway, Spain, Sweden and the USA. The Norwegian participation is financed by ENOVA SF, and SINTEF Energy Research is responsible for planning and carrying out the Norwegian activities. This report provides a status for ground-source heat pump (GSHP) systems in Norway with regard to state-of-the-art technology, installation examples, geological data, costs and market opportunities. A Norwegian Internet home page for ground-source heat pump systems (www.energy.sintef.no/prosjekt/Annex29) is also presented. GSHP systems in Norway are classified as direct systems (groundwater and soil/ground) and indirect ...
Two major developments have given impetus to wider adoption of variable-speed turbine/generators in hydroelectric plants, both essentially environmental: (1) the need for stream-bed stability below river dams, and (2) the need to minimize fish damage. Also, the need to stabilize pumped-storage and generating efficiencies to match extreme changes in head levels has been a driving force. Variable-speed operation in hydro applications is relatively new to North America. In other parts of the world, it has been used in pumped-storage plants since 1971. In the US, and increasing potential exists for variable-speed hydro, considering the 30 pumped-storage plants already in operation and several river plants struggling with high head fluctuations--including four at stations operated by the Bonneville Power Administration. Several modifications to hydro-plant hardware and operating procedures are actively being considered at ...
Energy savings performance contracting (ESPC) is now receiving greater attention as a means of implementing large-scale energy conservation projects in housing. Opportunities for such projects exist for military housing, federally subsidized low-income housing, and planned communities (condominiums, townhomes, senior centers), to name a few. Accurate prior (to construction) estimates of the energy savings in these projects reduce risk, decrease financing costs, and help avoid post-construction disputes over performance contract baseline adjustments. This paper demonstrates an improved method of estimating energy savings before construction takes place. Using an engineering model calibrated to pre-construction energy-use data collected in the field, this method is able to predict actual energy savings to a high degree of accuracy. This is verified with post-construction energy-use data from a geothermal heat pump ESPC at Fort Polk, Louisiana. This method also allows ...
Energy savings performance contracting (ESPC) is now receiving greater attention as a means of implementing large-scale energy conservation projects in housing. Opportunities for such projects exist for military housing, federally subsidized low-income housing, and planned communities (condominiums, townhomes, senior centers), to name a few. Accurate prior (to construction) estimates of the energy savings in these projects reduce risk, decrease financing costs, and help avoid post-construction disputes over performance contract baseline adjustments. This paper demonstrates an improved method of estimating energy savings before construction takes place. Using an engineering model calibrated to pre-construction energy-use data collected in the field, this method is able to predict actual energy savings to a high degree of accuracy. This is verified with post-construction energy-use data from a geothermal heat pump ESPC at Fort Polk, Louisiana. This method also allows ...
Most pumped-storage plants have the capability to operate as synchronous condensers. As such, they can be brought on line very quickly to support system load requirements. However, one of the effects of making a rapid transition from synchronous condenser operation to turbine/governor operation is an initial reverse power flow into the machine. This reverse power flow can be very undesirable at a time when the system is calling for load support. On weak or isolated systems, this reverse power flow can lead to objectionable voltage and frequency dips in the system. With the proper utilization of a static frequency converter (SFC) and its associated controls and auxiliary switchgear systems, the reverse power flow resulting from a transition from synchronous condenser operation can be eliminated. This paper will describe the method by which an SFC system can be used to make this rapid load response in pumped-storage plants without incurring a ...
The Versatile Toroidal Facility (VTF) is a large laboratory plasma machine of 1 meter major radius used to carry out investigations of ionospheric plasma turbulence. Spectral analysis has been performed on plasmas produced by the electron emitters. Interest has focused on the low frequencies below the lower hybrid resonance where ion acoustic and current-convective modes have been observed. Microwaves injected from a 3,000 watt magnetron produce dramatic changes to the low frequency spectrum. First, the parametric decay instability intensifies the ion acoustic modes in the region of plasma heated by the microwaves. Second, the normally dominant current-convective modes are greatly suppressed in the heated region due to the oscillating electric field of the pump wave. When the authors probe beyond the heated region, these two pump wave effects are no longer observed, presumably because the microwaves are denied access to beyond the heated region ...
The K0.5 for intracellular sodium of the two forms of (Na ,K )-ATPase which exist in rat adipocytes has been determined by incubating the cells in the absence of potassium in buffers of varying sodium concentration; these conditions shut off the Na pump and allow sodium to equilibrate into the cell. The activity of (Na ,K )-ATPase was then monitored with YWRb /K pumping which was initiated by adding isotope and KCl to 5 mM, followed by a 3-min uptake period. Atomic absorption and SSNa tracer equilibration were used to determine the actual intracellular (Na ) under the different conditions. The K0.5 values thus obtained were 17 mM for alpha and 52 mM for alpha(+). Insulin treatment of rat adipocytes had no effect on the intracellular (Na+) nor on the Vmax of YWRb /K pumping, but did produce a shift in the sodium ion K0.5 values to 14 mM for alpha and 33 mM for alpha(+). This change in affinity can explain the selective ...
Non-evaporable thin film getters of various compositions have been produced by sputtering. Among about 20 materials which have been studied, the lowest activation temperature (about 180 degree C) has been displayed by a Ti-Zr-V coating obtained from a cathode made of intertwisted elemental wires. In order to optimize the vacuum properties of this film various production parameters, including the substrate temperature during coating, have been varied. The films have been characterized by pumping speed measurement, secondary electron microscopy, and X-ray diffraction. It has been found that the substrate coating temperature affects significantly the activation temperature, the pumping speed and the gas surface capacity. The highest pumping speed values, obtained for substrate coating temperatures of 250 degree C and 300 degree C, are clearly correlated with the increased surface roughness and porosity of the Ti-Zr-V film.
Environmental targets and saving energy have become ones of the world main concerns over the last years and it will increase and become more important in a near future. The world population growth rate is the major factor contributing for the increase in global pollution and energy and water consumption. In 2005, the world population was approximately 6.5 billion and this number is expected to reach 9 billion by 2050 [United Nations, 2008. (www.un.org), accessed on July]. Water supply systems use energy for pumping water, so new strategies must be developed and implemented in order to reduce this consumption. In addition, if there is excess of hydraulic energy in a water system, some type of water power generation can be implemented. This paper presents an optimization model that determines the best hourly operation for 1 day, according to the electricity tariff, for a pumped storage system with water consumption and inlet discharge. Wind ...
A statistical survey is conducted of air pollution in the city of Rome (Italy) due to conventional building space heating systems burning fossil fuels. The survey identifies the annual consumption of the different fuels and the relative amounts of the various pollutants released into the atmosphere by the heating plants, e.g., sulfur and nitrogen oxides, carbon monoxide, etc. Comparisons are then made between the ratios of urban heating plant air pollutants produced per tonne of fuel employed and those for ENEL (Italian National Electricity Board) coal, oil and natural gas fired power plants, in order to demonstrate the better environmental performances of the utility operated energy plants. The building space heating system energy consumption and pollution data are then used in a cost benefit analysis favouring the retrofitting of conventional heating systems with heat pump systems to obtain substantial reductions in energy consumption, heating bills and urban air ...
The Geothermal Heat Pump (GHP) concept was originally developed in the 1940`s. Recently, because of increasing energy costs, utility interest, and the development of simple and durable ground source heat exchangers, GHP`s have gained international attention as a proven means of energy conservation and electrical peak power demand reduction. GHP systems require installation of a buried heat exchanger to utilize the nearly constant ground temperature making them more efficient than conventional air source heat pumps. However, the high installation cost for both residential and commercial applications is a major obstacle to their market penetration. Sandia National Laboratories (SNL) through its sponsors, the Department of Energy (DOE), and the Department of Defense (DOD), has embarked on a research program to find ways to reduce GHP installation costs and improve performance, thereby increasing their market penetration. The major elements of the ...
A multi-faceted research program has been performed to investigate in detail several aspects of free and forced convective cooling of underground electric cable systems. There were two main areas of investigation. The first one reported in this volume dealt with the fluid dynamic and thermal aspects of various components of the cable system. In particular, friction factors for laminar flow in the cable pipes with various configurations were determined using a finite element technique; the temperature distributions and heat transfer in splices were examined using a combined analytical numerical technique; the pressure drop and heat transfer characteristics of cable pipes in the transitional and turbulent flow regime were determined experimentally in a model study; and full-scale model experimental work was carried out to determine the fluid dynamic and thermal characteristics of entrance and exit chambers for the cooling oil. The second major area of activity, reported in volume 2, ...
The integrity of the cables located in the target room is very important in the Fire PSA, because the CDF and CCDP are changed according to the results of a cable integrity that depends on the surrounding gas temperature. The conservative assumptions used in the Fire PSA typically specify that all of the equipment and cables of a room would fail when a fire happens in the room. But the realistic assessment of a fire risk by using a fire simulation tool has become necessary in the Fire PSA as described in the ANS Fire PRA Standard. This paper evaluates the cable integrity of eight pump rooms in the nuclear power plant by using the CFAST zone fire model. The upper layer gas temperature of each room is estimated, and an analysis based on the results of model simulations is used to judge the cable integrity. According to the analysis results, the integrity of the cable located in the upper layer in the pump rooms is maintained without any thermal ...
Based on a collisional-radiative model, an atomic-kinetic calculation of the gains on the 41.8-nm transitions of Pd-like xenon was performed for the plasma produced due to the interaction of a femtosecond laser pulse with gaseous xenon. The gains g(z,{tau}) averaged over the spatial and temporal coordinates were compared with the known gains which had been measured experimentally in Xe{sup 8+}. The amplification was shown to occur under the conditions of ionisation of the working ions, and the time of output radiation saturation depends on the time of Xe{sup 8+} transformation to higher-ionised ions. Our theoretical investigation enables determining the optimal pump parameters, at which the product of the gain g by the active medium length L is about 20, which exceeds the experimental gL value. (active media)
Based on a collisional-radiative model, an atomic-kinetic calculation of the gains on the 41.8-nm transitions of Pd-like xenon was performed for the plasma produced due to the interaction of a femtosecond laser pulse with gaseous xenon. The gains g(z,?) averaged over the spatial and temporal coordinates were compared with the known gains which had been measured experimentally in Xe8+. The amplification was shown to occur under the conditions of ionisation of the working ions, and the time of output radiation saturation depends on the time of Xe8+ transformation to higher-ionised ions. Our theoretical investigation enables determining the optimal pump parameters, at which the product of the gain g by the active medium length L is about 20, which exceeds the experimental gL value. (active media)
In order to match the output capacity of a geothermal heat pump system (GHPS) with the actual load requirement, research has been conducted in searching for suitable adjusting methods for the GHPS and on the subsequent effects on the working parameters of the GHPS. Firstly, several methods are compared, and it is found that the method of adjusting the compressor's rotation speed using a transducer is better than the others. Secondly, this method is experimented on a small scale GHPS at frequencies ranging from 30 to 55 Hz. The analysis of the experimental data reveals the relationships between the compressor frequency and other important parameters, such as coefficient of performance, heat capacity, cool capacity and compressor power input. The conclusions in the paper can serve as some guidance to the load adjustment of GHPS. (Author)
This paper studies the effects of axial heat conduction in boreholes used in geothermal heat pump systems. The axial effects are examined by comparing the results obtained using the finite and infinite line source methods. Using various practical design problems, it is shown that axial effects are relatively important. Unsurprisingly, short boreholes and unbalanced yearly ground loads lead to stronger axial effects. In one example considered, it is shown that the borehole length is 15% shorter when axial conduction effects are considered. In another example dealing with underground water freezing, the amount of energy that has to be removed to freeze the ground is three times higher when axial effects are considered. (author)
A geothermal heat pump (GHP) system with three ground coils was installed in a residence in northern Idaho with a portion of the ground heat exchanger wrapped around the residential septic tank. The septic coil provided a significant portion of the heating for the residence over the heating season. There was no evidence of the septic tank freezing up or failing to properly function. Utilizing a septic tank as a heat source for GHP systems is feasible design option if the septic tank is used on a full-time basis. However, the tank should be surrounded on all sides by a large amount of soil and/or insulated from the ground surface to ensure that ground temperatures near the tank remain warm during the winter.
We present the design of a diagnostic system to measure electron cyclotron absorption at the second harmonic E-mode resonance in the JET pumped divertor plasma. The diagnostic will measure transmission as a function of frequency along one or more sightlines from which the spatial profile of the n_eT_e product will be deduced. The divertor is briefly described, and the electron cyclotron resonance physics relevant to this measurement is reviewed. The problems of measuring transmission using an oversized transmission system are discussed and the chosen measurement technique, a swept frequency interferometer using a coherent radiation source, is described. A prototype of the instrument has been assembled to test the measurement technique. Some data demonstrating the instrument's characteristics are presented. The nonresonant losses, which may affect the interpretation of the measurement, are also discussed. (orig.).
The mapping of the magnetic flux bundle from the center cell to the Plasma Potential Control plates (PPC) on the end fan of the Tandem Mirror Experiment Upgrade (TMX-U), was improved by the addition of trim coils (12,000 amp-turns) on each side of each end fan next to the pump beam magnetic shields. The coils' axes are oriented perpendicular to the machine centerline. These coils made the necessary corrections to the field-line mapping, while keeping the field in the nearby pump beam magnetic shield below the saturation threshold. This paper briefly describes the problem, discusses the design as it evolved, and presents the results of the field testing. A brief description of the improvement in the machine performance is also included.
Ground-water monitoring near the Raft River site was initiated in 1974 by the IDWR. This effort consisted of semiannual chemical sampling of 22 irrigation wells near the Raft River geothermal development area. This program yielded useful baseline chemical data; however, several problems were inherent. For example, access to water pumped from the wells is limited to the irrigation season (April through September). All the wells are not continuously pumped; thus, some wells that are sampled one season cannot be sampled the next. In addition, information on well construction, completion, and production is often unreliable or not available. These data are to be supplemented by establishing a series of monitor wells in the proposed geothermal withdrawal and injection area. These wells were to be located and designed to provide data necessary for evaluating and predicting the impact of geothermal development on the Shallow Aquifer system.
Preliminary studies were preformed to determine whether thermal conductivity of cementitious grouts used to backfill heat exchanger loops for geothermal heat pumps could be improved, thus improving efficiency. Grouts containing selected additives were compares with conventional bentonite and cement grouts. Significant enhancement of grout alumina grit, steel fibers, and silicon carbide increased the thermal conductivity when compared to unfilled, high solids bentonite grouts and conventional cement grouts. Furthermore, the developed grouts retained high thermal conductivity in the dry state, where as conventional bentonite and cement grouts tend to act as insulators if moisture is lost. The cementitious grouts studied can be mixed and placed using conventional grouting equipment.
The kWh model finds the kWh outputs of each plant and reservoir capacities of hydro and pumped storage plants and minimizes the sum of fixed charges for constructing the reservoirs and generating facilities, also the fuel costs of thermal and nuclear plants. It is a linear programming problem whose constants are represented by nonlinear functions of kW running capacity of each plant. The optimal pattern of nuclear and thermal units is found by solving the linear programming problem derived for the pumped storage and hydroplants. Excluding the upper bound constraints, the number of constraint equations are few and do not increase with the number of units, although the number of variables increases. The computing time increases only in proportion to the number of groupings of generating units. Sensitivity analysis can be done easily. The detailed operational behavior of each generating unit can be taken into account.
Object: To minimize the range of the liquid level variation of the cooling system and reduce the time required for the liquid level control by sealing the gas of a cover gas respiration system which acts upon an evaporator and pump overflow column. Structure: In liquid level control by the cover gas pressure of a high-speed reactor secondary cooling system, upon occurrence of a sudden change in the rate of flow of the recirculated liquid, automatic check valves provided in an evaporator and pump overflow column cover gas respiration system are completely or substantially closed, while at the same time the recirculation cooling medium is sucked up and an automatic check valve provided in the overflow system is closed. (Kamimura, M.).
In order to match the output capacity of a geothermal heat pump system (GHPS) with the actual load requirement, research has been carried out in finding the influence of two systematic parameters, the water flow rate inside the condenser and the compressor input frequency on the GHPS operation. Experiments are done on a small-scale GHPS at the water flow rate ranging from 0.054 kg/s to 0.174 kg/s and the frequency from 30 Hz to 55 Hz. The analysis of the experimental data reveals the relationships among the compressor frequency, the water flow rate and other important parameters such as coefficient of performance (COP), heat capacity and compressor power input. The conclusions in the paper can serve as some guidance to the load adjustment of GHPS. (author)
In conventional power plants trash-racks are provided at the intakes to protect the turbines. In pumped storage plants, the draft tube or tailrace must also have trash-racks to protect the units while pumping. Because the loads believed to cause many failures of trash-racks are dynamic in nature, it is important to understand the dynamic characteristics of trash-racks structures in general and a single rack in particular. The classical added-mass solution structure-fluid dynamic interaction is known as an approximate solution procedure. An accurate added-mass approach mixed with implementation in finite element framework is proposed. In this proposal, experimental conclusions, supported by theory, led to presentation of more accurate results in vibration of trash-racks. This numerical solution as a powerful method to solve such a complex problem can be employed to carry out dynamic characteristics of these structures while vibrating in water.
The modeling and optimizing processes of a Ground Coupled Heat Pump (GCHP) with closed Horizontal Ground Heat eXchanger (HGHX) are presented in this paper. After thermal modeling of GCHP including HGHX, the optimum design parameters of the system were estimated by minimizing a defined objective function (total of investment and operation costs) subject to a list of constraints. This procedure was performed applying Genetic Algorithm technique. For given heating/cooling loads and various climatic conditions, the optimum values of saturated temperature/pressure of condenser and evaporator as well as inlet and outlet temperatures of the water source in cooling and heating modes were predicted. Then, for our case study, the design parameters as well as the configuration of HGHX were obtained. Furthermore, the sensitivity analysis of change in the total annual cost of the system and optimum design parameters with the climatic conditions, cooling/heating capacity, and ...
In the process of backward Raman amplification (BRA), the leading layers of the seed laser pulse can shadow the rear layers, thus weakening the effective seeding power and affecting parameters of output pulses in BRA. We study this effect numerically and also analytically by approximating the pumped pulse by the ''*-pulse'' manifold of self-similar solutions. We determine how the pumped pulse projection moves within the *-pulse manifold, and describe quantitatively the effective seeding power evolution. Our results extend the quantitative theory of BRA to regimes where the effective seeding power varies substantially during the amplification. These results might be of broader interest, since the basic equations, are general equations for resonant 3-wave interactions.
This paper presents a new method and newly developed stabilizing equipment to prevent the loss of synchronism of generators in pumped-storage plants from spreading. The proposed method includes functions to estimate the swing of each generator by using on-line generator output sampled at a rate of 600 times per second after an occurrence of disturbance such as fault, faulty equipment and so on, to predict generator swing 200-300 milliseconds ahead and loss of synchronism between generators in pumped-storage plants and those in thermal and nuclear plants, and to decide the number of generators that must be shed to maintain stability. Tokyo Electric Power Co. (TEPCO) installed the newly developed stabilizing equipment based on this method in the power system in June, 1986.
This paper presents a new method and newly developed stabilizing equipment to prevent the loss of synchronism of generators in pumped-storage plants from spreading. The proposed method includes functions to estimate the swing of each generator by using on-line generator output sampled at a rate of 600 times per second after an occurrence of disturbance such as fault, faulty equipment and so on, to predict generator swing 200-300 milliseconds ahead and loss of synchronism between generators in pumped-storage plants and those in thermal and nuclear plants, and to decide the number of generators that must be shed to maintain stability. Tokyo Electric Power Co. (TEPCO) installed the newly developed stabilizing equipment based on this method in the power system in June, 1986.
The scale-down of a liquid mini-pump (order of 10 mm) to a micrometre scale has been attempted using a novel valveless nozzle-diffuser design and new application of an organic physical vapor-deposited membrane. The micropump employs no moving parts other than the membrane and accomplishes the rectification of fluid flow due to pressure recovery differences in the nozzle and diffuser flow directions. More specifically, liquids flow with less resistance (i.e. conduct more fluid) in the diffuser direction than the nozzle direction, for a given pressure differential. At the micrometre scale, the fabrication of the critical nozzle and diffuser elements was performed by focused ion beam (FIB) microlithography of glass slides. Etched slides were sandwiched to make two-dimensional venturis. Sternme and Sternme noted the importance of a lower Reynolds Number linfit on the desired pressure recovery which challenged the fabrication of this pump design at ...
Analysis of the dynamics of the cavity radiation of a coherently pumped correlated emission laser is presented. The phase fluctuation and dephasing are found to affect the time evolution of the two-mode squeezing and intensity of the cavity radiation significantly. The intensity and degree of the two-mode squeezing increase at early stages of the process with time, but this trend changes rapidly afterwards. It is also shown that they increase with phase fluctuation and dephasing in the strong driving limit, however the situation appears to be opposite in the weak driving limit. This essentially suggests that the phase fluctuation and dephasing weaken the coherence induced by a strong driving mechanism so that the spontaneous emission gets a chance. The other important aspect of the phase fluctuation, in this regard, is the relaxation of the time at which the maximum squeezing is manifested as well as the time in which the radiation remains in a squeezed state.
Purpose: To remove excessive driving pressure applied to an unisolated control rod drive by returning excessive coolant to a condensed water storage tank or to the inlet side of a drive water pump using a coolant flow rate control pipe of a control rod driving hydraulic system. Constitution: Excessive water is returned to a condensed water tank while controlling the excessive coolant by a flow control valve in response to variations in the pressure difference between the reactor pressure and the driving water line when the control rods are isolated using a pipe from the outlet side of the drive water pump to the condensed water storage tank. Thus, the control rod to be isolated is prevented form being dropped. (Sekiya, K.).
The conceptual design for MCP to be installed in the integral reactor SMART was carried out. Canned motor pump was adopted in the conceptual design of MCP. Three-dimensional modeling was performed to visualize the conceptual design of the MCP and to check interferences between the parts. The theoretical design procedure for the impeller was developed. The procedures for the flow field and structural analysis of impeller was also developed to assess the design validity and to verify its structural integrity. A computer program to analyze the dynamic characteristics of the rotor shaft of MCP was developed. The rotational speed sensor was designed and its performance test was conducted to verify the possibility of operation. A prototypes of the canned motor was manufactured and tested to confirm the validity of the design concept. The MCP design concept was also investigated for fabricability by establishing the manufacturing procedures. 41 refs., 96 figs., 10 tabs. ...