The purpose of this work is to determine the extent to which drill water might be expected to be imbibed by core samples taken from densely welded tuff. In a related experimental study conducted in G-Tunnel, drill water imbibition by the core samples was observed to be minimal. Calculations were carried out with the TOUGH code with the intent of corroborating the imbibition observations. Due to the absence of hydrologic data pertaining directly to G-Tunnel welded tuff, it was necessary to apply data from a similar formation. Because the moisture retentioncurve was not available for imbibition conditions, the drainage curve was applied to the model. The poor agreement between the observed and calculated imbibition data is attributed primarily to the inappropriateness of the drainage curve. Also significant is the value of absolute permeability (k) assumed in the ...
The VE (ventilation) test carried out at the Mont Terri underground laboratory in Switzerland intended to evaluate in situ the behaviour of a consolidated clay formation when subjected to alternate periods of flow of wet and dry air during several months. For that, a 10-m gallery was excavated in the Opalinus Clay formation and carefully instrumented. Before and after a second ventilation phase boreholes were drilled. Samples were taken from the drill cores and were analysed from mineralogical and geochemical points of view. Also, the retentioncurves of these samples were determined in the laboratory following drying paths performed under free volume conditions at 20 degree centigrade, what is the content of this report. Although there are not large differences in the WRC of samples taken from different boreholes, at different distances from the gallery wall or before or after ventilation, those samples taken near the gallery wall and after ...
A series of copolymers based on the cellulose acetate/propionate-g.co-acrylic acid system has been prepared under radiation-induced control. These copolymers have been assessed for their water-retention capacity both in an unmodified state and after ''decrystallization'' or ''neutralization'' treatments. The grafting of acrylic acid onto the cellulose acetate/propionate had little effect on the waterretention power of the cellulose acetate/propionate. However, improvements to the waterretentivity was obtained after ''decrystallization'' procedures had been carried out on the copolymers using selected alkali metal salts with methanol as the continuous medium. The water-retentivity of the copolymers increased with increase in the extent of grafting, though ...
In this paper the diffusion of tritiated water vapor into concrete walls is studied to evaluate tritiated waterretention capacity of a fusion reactor concrete building. Using a model of the tritiated water diffusion determined form experimental results, depth profiles of tritiated water in concrete are calculated in the case of being exposed to air containing tritiated water vapor during the normal operational condition of a fusion reactor. A 0.5-m-thick concrete is sufficient for reactor hall walls from a viewpoint of the tritium containment.
In this paper the diffusion of tritiated water vapor into concrete walls is studied to evaluate tritiated waterretention capacity of a fusion reactor concrete building. Using a model of the tritiated water diffusion determined form experimental results, depth profiles of tritiated water in concrete are calculated in the case of being exposed to air containing tritiated water vapor during the normal operational condition of a fusion reactor. A 0.5-m-thick concrete is sufficient for reactor hall walls from a viewpoint of the tritium containment.
Coal bed natural gas (CBNG) development in the Powder River (PR) Basin produces modestly saline, highly sodic wastewater. This study assessed impacts of wetting four textural groups (0-11%, 12-22%, 23 -33%, and > 33% clay (g clay/100 g soil) x 100%))with simulated PR or CBNG water on waterretention. Soils received the following treatments with each water quality: a single wetting event, five wetting and drying events, or five wetting and drying events followed by leaching with salt-free water. Treated samples were then resaturated with the final treatment water and equilibrated to -10, -33, -100, -500, or -1,500 kPa. At all potentials, soil waterretention increased significantly with increasing clay content. Drought-prone soils lost water-holding capacity between saturation and field ...
The retention of radio-Eu, Go, Cs and Sr, at the tracer level, on raw fibers produced from hemp, linen and Jute plants was investigated. The study was conducted from different media including: sea and tap waters, sodium chloride and nitric acid solutions of different Ph. The percentage retention and elution, on prolonged contact, varied from one element to another depending on conditions. Extraction chromatography columns, using these fibers as supporting material were also experimented. Results were discussed together with possible applications. 7 tabs.
We have studied, by a Monte Carlo simulation code ACAT-DIFFUSE, the fluence-dependence of the amount of retained helium atoms in tungsten carbide at room temperature under helium ion bombardment. The retention behavior may be understood qualitatively in terms of irradiation-dependent diffusion coefficient assumed and range. The emission processes from tungsten carbide under helium ion irradiation derived were compared with each other. We have discussed the retentioncurves for incident energy of 5 keV at incident angles of 0deg and 80deg and of 500 eV at 0deg. The energy spectra of helium atoms reflected from tungsten carbide for incident energy of 500 eV at 0deg and 80deg were compared with those from graphite and tungsten. (author)
Molybdenum dioxo bis acetylacetonate shows a retention of about 31% for both "9"9Mo and "1"0"1Mo, with reactor irradiations at ambient temperature. But its radiolytic stability and resistance to hydrolysis are too low for application to "9"9Mo enrichment. The molybdenum (II) carboxylates and the arene molybdenum (O)tricaronyls show high retentions. These complexes are also air and water sensitive in solution. (orig.).
Radiation modification on liquid retention properties of native cassava starch, gelatinized at 85"0C, by graft copolymerization with acrylonitrile was carried out by mutual irradiation to #gamma#-rays. A thin aluminium foil was used to cover the inner wall of the reaction vessel so that the extent of homo polymer could be reduced to be less than 1.6% with a distilled waterretention value of 665 g/g of the dry weight of the saponified grafted product. Confirmations of graft copolymerization and saponification reactions were made by the infrared spectrophotometric technique. The combined effect of radiation parameters in terms of an irradiation time and a dose rate to the same total dose on the extent of grafting reaction expressed in terms of grafting parameters which directly influenced liquid retention values was evaluated in conjunction with statistical analysis.
The results of the thermo-hydro-mechanical (THM) study of the FEBEX bentonite performed during FEBEX II are presented. The laboratory test program continued in part with the works carried out during FEBEX I, particularly in activities related to tests aimed to the calibration of the models, the acquisition of parameters by back-analysis and the improvement of the knowledge on the behaviour of expansive clays. But the program has also included tests on new areas: investigations about the influence of the microstructure changes in bentonite, of temperature and of the solute concentration on the behaviour of clay. Besides, several tests were proposed in order to understand the unexpected behaviour observed in the mock-up test, towards the end of year 2. Temperature effects on waterretentioncurves in confined and unconfined conditions were determined, and swelling pressure, hydraulic conductivity and swelling and ...
Haemocyanin serves as normal transporter of oxygen in many Arthropods. The oxygen equilibrium curves have been described for the haemocyanins of many Arthropods and Molluscs. Oxygen equilibrium curves of the blood reveal the relationship between the oxygen tension and the percentage saturation of the haemocyanin. The shape of the oxygen equilibrium curves vary in position from sigmoid to hyperbolic in different animals or even undulatory as shown in some chitons. Oxygen equilibrium curves are known to be influenced by pH, temperature and inorganic ions. The effect of environmental pollutants like the heavy metals on the oxygen equilibrium curves of the fresh water crab has not been previously reported. One of the toxic heavy metals with regard to aquatic organisms is lead. Hence the present study was designed to determine the effect of organic and inorganic lead ...
The soil water characteristic curve, h(theta), can be used to estimate a variety of parameters in unsaturated soils. One practical application of h(theta) is its use by DRAINMOD, a drainage model that has been widely used in shallow water table regions, to determine the water table depth¿drainage v...
A study of the effect of a clayey soil modified in situ and ex situ with the cationic surfactant octadecyltrimethylammonium bromide (ODTMA), on the retention of linuron, atrazine and metalaxyl was carried out. Leaching of these compounds was studied in columns of a natural clayey soil and the same clayey soil modified by direct injection of the surfactant in situ, and in columns of a natural sandy soil and the same sandy soil modified by intercalation of a barrier of the clayey soil saturated ex situ with the surfactant. Breakthrough curves indicated the total immobilization of linuron in modified soils and a decrease in the leaching kinetics of atrazine and metalaxyl compared to what was obtained in the natural soil. The results indicate the use of the clayey soil modified in situ or ex s...
We describe a compact ultrafiltration system for the removal of pyrogens and bacteria from water labeled with the stable isotopes of deuterium and oxygen-18. The ultrafiltration system is constructed from readily available commercial components and can achieve complete removal of pyrogens and bacteria from 1L contaminated water within 30 min. By use of our procedure, loss of the isotopically labeled water by retention in the filtration system was minimal. The purified water is suitable for both oral and intravenous administration to healthy human subjects participating in nutrition studies.
Indirect evaporative air coolers that use air-to-air plate-type heat exchangers show good promise (compared with compression air-conditioning systems) of extending the energy savings from arid, low-humidity areas to more widespread climatic conditions. However, no systematic experiment had been done concerning the effect of the wettability of aluminum plates on the effectiveness of the indirect evaporative cooling system. In this study, a testing apparatus was built where only one secondary channel and two primary channels were used so that different surfaces could be easily tested to determine the system`s effectiveness and the heat transfer coefficient. The advantage of this experimental apparatus is that plates of the heat exchanger can be easily changed in the test section instead of fabricating a complete heat exchanger for each test. A dynamic contact analyzer was used to quantitatively measure the wetting properties in terms of advancing and receding contact angles and the ...
A new filtration process using acrylic fiber has been developed which has wide applications in water works, sewage water treatment and waste water treatment facilities. Instead of sand, the common filter media in conventional systems, this new system uses long, fine acrylic fibers. Compared with a conventional system, the filtration speed and suspended solids (SS) retention of the new system have been increased 500% from 120--200 m/d to 400--1,200 m/d and from 2--3 kg/m{sup 2} to 5--20 kg/m{sup 2}, respectively. In addition, the backwash time has been decreased 60%, from 20--30 min to 10 min. As SS retention increase, the empty space between the fibers (fiber void) decreases and pressure drops due to the high filtration rate. Thus the pressure decreases rapidly after a certain period of filtration because of the increased SS retention cause fiber compression. ...
An insulated letter drop plate comprises a back plate having an opening for the mail having two hinges at its upper part to attach a cover to; a frame for retaining a first insulation around its perimeter and around the opening; and suitable insulation. This back plate is also provided with an upper curved extension to cover and conceal said hinges. A cover is provided with two complementary hinges to be articulated with the first hinges on the back plate, and with a frame around the perimeter for the retention of a second insulation. A wire joins the first and second hinges, and a coil spring on the wire keeps the cover normally closed.
Retention kinetics and tissue partition coefficients for "8"5Kr were determined in rats exposed to known concentrations of "8"5Kr gas. The tissue partition coefficients were used to calculate the relative tissue radiation dose, assuming exposure conditions equivalent to the maximum permissible concentration in air (MPC)a. The estimated radiation dose was highest in adrenals and body fat, about twice the dose estimated for the next highest tissue, ovaries. Saturation and desaturation curves show that the contents of the large intestines have a prolonged desaturation time compared to other samples analyzed.
A fusion reactor (such as NET/ITER) which breeds its own tritium fuel requires tritium recovery, purification and separation from the other isotopes. Cyclic adsorption processes are strong candidates for several of the processes involved: amongst other advantages, they promise a low tritium inventory. A good adsorbent for such processes must have high adsorption capacity, high selectivity and very low tritium retention after each cycle. Pure zeolite powder is shown to have an excellent combination of these three properties. However, in practice problems can arise from tritium which is not removed by reactivation. In this paper we show that tritium retention in zeolites can be caused either by water retained in the zeolite structure, which can be removed by ore rigorous activation, or by water tapped on binders in commercial pellets. (orig.).
This report consists of appendices A-F containing the biological data which were collected from Lake Roosevelt, Washington. The data are to be used in the design of a computer model that would predict biological responses of reservoir operations as part of the System Operation Review program. Major components of the model included: Quantification of impacts to phytoplankton, zooplanktons, benthic invertebrates, and fish caused by reservoir drawdowns and low waterretention times; quantification of number, distribution, and use of fish food organisms in the reservoir by season; determination of seasonal growth of fish species as related to reservoir operations, prey abundance and utilization; and quantification of entrainment levels of zooplankton and fish as related to reservoir operations and waterretention times.
The Dowex 50W-X8 and 50W-Xl2 resin samples are both strong acid cation materials in the hydrogen form. Each material has a waterretention capacity characteristic of its respective marketed degree of cross-linking. Dowex 21K gives confirmatory responses to tests for a strong anion exchange resin in the nitrate form. All three resins have the manufacturer's specified ionic type and form, and the Dowex 50W resins have characteristic waterretention capacities. These tests conclude that the ion exchange resins in use in FB-Line meet the approved safety document criteria for cross-linking, ionic form, and resin type.
The Dowex 50W-X8 and 50W-Xl2 resin samples are both strong acid cation materials in the hydrogen form. Each material has a waterretention capacity characteristic of its respective marketed degree of cross-linking. Dowex 21K gives confirmatory responses to tests for a strong anion exchange resin in the nitrate form. All three resins have the manufacturer`s specified ionic type and form, and the Dowex 50W resins have characteristic waterretention capacities. These tests conclude that the ion exchange resins in use in FB-Line meet the approved safety document criteria for cross-linking, ionic form, and resin type.
A field study (1993-96) assessed the benefits of applying unusually high rates of coal fly ash from power plants as a soil amendment to enhance waterretention of soils without adversely affecting growth and marketability of the turf species, centipedegrass (Eremochloa ophiuroides (Munro) Hack.) A Latin Square plot design was employed that included 0 (control, no fly ash applied), 280, 560 and 1120 MgHa {sup -1} application rates of unweathered precipitator fly ash. The fly ash was spread evenly over each plot area, rototilled, and allowed to weather under natural conditions for 8 months before seeding. High levels of soluble salts, indicated by the electrical conductivity of soil extracts, in tandem with an apparent phytotoxic effect from boron, apparently inhibited initial plant establishment as shown by substantially lower germination counts in treated soil. However, plant height and rooting depth were not adversely affected, as were the dry ...
Experiments were conducted with field-grown cotton (Gossypium hirsutum L.) in 1985 and 1986 to determine effects of water deficit on levels of conjugated indole 3-acetic...Full Text Available
Yucca Mountain, Nevada is a potential site for a high-level radioactive-waste repository. Uncertainty and sensitivity analyses were performed to estimate critical factors in the performance of the site with respect to a criterion in terms of pre-waste-emplacement ground-water travel time. The degree of failure in the analytical model to meet the criterion is sensitive to the estimate of fracture porosity in the upper welded unit of the problem domain. Fracture porosity is derived from a number of more fundamental measurements including fracture frequency, fracture orientation, and the moisture-retention characteristic inferred for the fracture domain.
Cement-based composites are widely used in applications which demand long-term service life. One important example is in immobilization matrices for low-level radioactive and other hazardous wastes, which demands long-term retention and durability. The authors describe conductivity measurements of grouts flooded with water and in contact with a sink that consists of pure water. The conductivity measurements were designed and carried out in parallel with present quality verification methods and standard leach tests of the nuclear waste management industry. For the first time, the authors show that the method of replacing intrusive chemical analysis with conductivity measurements of the leaching samples yields equivalent results.
Water protection wetlands aim to reduce nitrogen and phosphorous concentrations either separately or simultaneously. In the latter case, a wetland must contain parts differing clearly in both function and physical condition. In efforts to reduce nitrogen the most important process is denitrification. Phosphorus is deposited with solids and bound to the vegetation and soil in wetlands. As the bulk of the solid and nutrient load comes from catchments during spring floods, wetlands should be designed on the basis of, at least, the average maximum vernal run-off (MHq). Use of higher run-offs, e.g. MHql/10 or MHql/20, in the design without reducing the target retention would require large wetlands. The efficiency of wetlands is constrained by too short retention times and low leachate temperatures. Wetlands established with special environmental support are normally designed on the basis of MHq. The average catchment area of ...
The results of the laboratory studies performed by CIEMAT with the FEBEX bentonite in the context of WP3.2 of the NF-PRO Project and of the Agreement ENRESA-CIEMAT Anexo V are presented and analysed in this report. They refer to the effect of the hydraulic gradient on the permeability of bentonite, the effect of the thermal gradient on the hydration kinetics of bentonite, and the repercussion of temperature on the hydro-mechanical properties of bentonite (swelling, permeability and waterretention capacity). In all the cases the bentonite has been used compacted to densities expected in the engineered barrier of a high-level radioactive waste repository. The existence of threshold and critical hydraulic gradients has been observed, both of them dependent on bentonite density and water pressures. After more than seven years of hydration, the 40-cm high bentonite columns are far from full saturation, the thermal gradient ...
The results of the laboratory studies performed by CIEMAT with the FEBEX bentonite in the context of WP3.2 of the NF-PRO Project and of the Agreement ENRESA-CIEMAT Anexo V are presented and analysed in this report. They refer to the effect of the hydraulic gradient on the permeability of bentonite, the effect of the thermal gradient on the hydration kinetics of bentonite, and the repercussion of temperature on the hydro-mechanical properties of bentonite (swelling, permeability and waterretention capacity). In all the cases the bentonite has been used compacted to densities expected in the engineered barrier of a high-level radioactive waste repository. The existence of threshold and critical hydraulic gradients has been observed, both of them dependent on bentonite density and water pressures. After more than seven years of hydration, the 40-cm high bentonite columns are far from full saturation, the thermal gradient ...
The objective of the project was to develop a welded tubular joint database to assess the fatigue design curves (X and X{prime}) in the American Petroleum Institute design code (API RP2A). Changes in the curve-fitting method and screening criteria (primarily the exclusion of the very thin tubular joints) produced results different from those reported previously. The current results show that the X and X{prime} curves are too conservative and that a new curve should be adopted. The Department of Energy T{prime} curve was found to be consistent with the screened tubular joint air data and is recommended for use in API RP2A. The weldment size effect exponent (n) of 0.25 in the current version of API RP2A was found to be too small, and a higher value of 0.30 consistent with the Department of Energy recommendations is recommended. The fatigue test results for tubular joints tested in air ...
The ORNL high temperature isopiestic apparatus was adapted for adsorption measurements. The quantity of water retained by rock samples taken from three different wells of The Geysers was measured at 150 °C and at 200 °C as a function of pressure in the range 0.00 ≤ p/p0 ≤ 0.98, where p0 is the saturated water vapor pressure. The rocks were crushed and sieved into three fractions of different grain sizes (with different specific surface areas). Both adsorption (increasing pressure) and desorption (decreasing pressure) runs were made in order to investigate the nature and extent of the hysteresis. Additionally, BET surface area analyses were performed by Porous Materials Inc. on the same rock samples using nitrogen or krypton adsorption measurements at 77 K. Specific surface areas and pore volumes were determined. These parameters are important in estimating ...
Different concrete waste packages have been designed by Electricite de France (EDF) for the long-term storage of radioactive Low Level Waste (LLW). Their main function is to confine radionuclides from the biosphere for three hundred years in a near-surface disposal. According to the transport regulations, a Type-B package is needed for some waste like water filters. The water filters from EDF nuclear power plants are encapsulated in mortar and placed in a concrete container. Transport regulations for these containers have required the development of a methodology for safety assessment. The reference scenario of container degradation during transport considers a 9 m drop and a 800"oC fire for 30 min. First, the different chemical and physical processes involved in the containment of radionuclides are analysed. In particular, the radionuclide transport mechanisms in cement-based materials have been reviewed. Secondly, the effects of a container ...
This paper proposes a model to explain tritium release behavior of an irradiated Li_4SiO_4 sample made by Forschungszentrum Karlsruhe. The release curves were obtained in a series of experiments carried out using out-pile temperature programmed desorption techniques in the Kyoto University Reactor (KUR). Tritium release curves obtained for different purge gas compositions (N_2, N_2 + H_2, N_2 + H_2O) were compared for selection of suitable conditions to determine the apparent diffusivity of tritium in a crystal grain of Li_4SiO_4.In the model formation, some mass transfer steps in the bulk of the crystal grain and those on the surface of the grain were taken into account, which were diffusion of tritium in the grain, adsorption and desorption of water on the surface of the grain, two types of isotope exchange reactions, and water formation reaction by the addition of hydrogen to the purge ...
A study of stress corrosion cracking susceptibility of Zircaloy-4 in chloride-containing aqueous methanolic media is presented. The influence of water content is investigated in the 5-100 vol. % water range. The dependence of stress corrosion cracking on potential is evidenced. A close correlation is established with pitting susceptibility determined by a statistical analysis of induction times. A correlation with the repassivation potential is observed in the water-rich solutions. In the low water content solutions, two repassivation curves are determined according to the experimental technique. Pit morphology and fractography show a transition from aqueous to organic media. (author).
This paper examines how robust economic, political, and demographic variables are related to water and air pollution. Employing Bayesian Averaging of Classical Estimates (BACE) for a cross section of 47 countries, 34 variables and 3 proxies for air and water pollution over a period from 1980 to 2000 we confirm the environmental Kuznets curve hypothesis and highlight the relevance of variables that are not directly related to production.
The corrosion rate of low alloy steel SA-508 and carbon steel A-410b in simulated operation and shutdown conditions of pressurized water reactor has been determined Moreover potentiodynamic polarization curves and galvanic effect through coupling of AISI-304 have been carried out under shutdown simulated condition. (Author) 8 refs.
This study revisits the environmental Kuznets curve (EKC) hypothesis for water pollution by using a recent dynamic technique, which is the generalized method of moments (GMM) approach, for a board sample of 97 countries during the period 1980-2001. On a global scale, as we cannot obtain the EKC relationship between real income and biological oxygen demand (BOD) emissions, this paper further classifies these countries into four regional groups - Africa, Asia and Oceania, America, and Europe - to explore whether the different regions have different ECK relationships. The empirical results show evidence of the inverted U-shaped EKC relationships' existence in America and Europe, but not in Africa and Asia and Oceania. Thus, the regional difference of EKC for water pollution is supported. Furthermore, the estimated turning points are, approximately, US$13,956 and US$38,221 for America and Europe, respectively.
This study revisits the environmental Kuznets curve (EKC) hypothesis for water pollution by using a recent dynamic technique, which is the generalized method of moments (GMM) approach, for a board sample of 97 countries during the period 1980-2001. On a global scale, as we cannot obtain the EKC relationship between real income and biological oxygen demand (BOD) emissions, this paper further classifies these countries into four regional groups - Africa, Asia and Oceania, America, and Europe - to explore whether the different regions have different ECK relationships. The empirical results show evidence of the inverted U-shaped EKC relationships' existence in America and Europe, but not in Africa and Asia and Oceania. Thus, the regional difference of EKC for water pollution is supported. Furthermore, the estimated turning points are, approximately, US$13,956 and US$38,221 for America and Europe, respectively.
This study revisits the environmental Kuznets curve (EKC) hypothesis for water pollution by using a recent dynamic technique, which is the generalized method of moments (GMM) approach, for a board sample of 97 countries during the period 1980-2001. On a global scale, as we cannot obtain the EKC relationship between real income and biological oxygen demand (BOD) emissions, this paper further classifies these countries into four regional groups - Africa, Asia and Oceania, America, and Europe - to explore whether the different regions have different ECK relationships. The empirical results show evidence of the inverted U-shaped EKC relationships' existence in America and Europe, but not in Africa and Asia and Oceania. Thus, the regional difference of EKC for water pollution is supported. Furthermore, the estimated turning points are, approximately, US$13,956 and US$38,221 for America and Europe, respectively. (author)
Differential Scanning Calorimetry (DSC) is employed to study the changes in enthalpy of natural rubber latex samples when heated under a controlled temperature program. It is found that the mass normalized areas of the DSC curves between room temperature and 170??C for different latex samples are inversely proportional to the dry rubber content (DRC) of the samples, measured following the weighing and drying method. The changes in total enthalpy of the samples in this temperature range are interpreted as due to the variations in the quantity of water present in the samples. The measurements have been repeated by diluting selected samples with known quantities of water, and it is found that the normalized areas of the DSC curves are directly proportional to the amount of water added to the ...
This document is a summary of the available information on the thermo-hydro-mechanical properties of the bentonite barrier of a high-level radioactive waste repository and of the processes taking place in it during the successive repository operation phases. Mainly the thermal properties, the volume change processes (swelling and consolidation), the permeability and the waterretention capacity are analysed. A review is made of the existing experimental knowledge on the modification of the these properties by the effect of temperature, water salinity, humidity and density of the bentonite, and their foreseen evolution as a consequence of the processes expected in the repository. The compiled evolution refers mostly to the FEBEX (Spain), the MX-80 (USA) and the FoCa (France) bentonite, considered as reference barrier materials in several European disposal concepts. (Author) 102 refs.
This paper deals with the energy required to separate ethanol from an aqueous solution in a distillation column containing a solid phase. The solid phases evaluated consisted of either an amylatious (ground corn) or a cellulose (sugar cane bagasse) absorber whit particle sizes smaller than 4 mm. The water-retention capacity of each solid phase was measured by passing vapors or ethanol-water mixtures through the solid phase. When starting with initial concentrations bellow the azeotropic point, ethanol concentrations up to 99,5% (on corn) and 97,2% (on sugar cane) were achieved. The water content was evaluated potentiometrically (Karl`Fischer). Regarding the 2-4 mm ground corn solid phase column, the energy consumed was estimated to be reduced by 15,6% and 60% (by weight) ethanol-water mixture respectively. (author) 11 refs., 2 figs., 2 tabs
Water injection into a vapor-dominated geothermal reservoir is an effective method of sustaining steam production from the field. Injection puts additional water to the reservoir and raises the prevailing reservoir pressure. This process improves the field`s productivity. However, the increased pressure also increases the waterretention capacity of the reservoir rocks through the effects of adsorption and capillary condensation. Due to the significant costs associated with water injection programs, optimizing injection not only involves maximizing the energy yield from the resource but also the present worth of the project. Two crucial parameters that need to be established are: (1) how much to inject; and, (2) when to inject it. This study investigated the optimal design of these parameters. It was found that comparable energy yield can be attained for injection programs that are ...
It is needless to say that one of the most important roles of the condensate demineralizer in Japanese boiling water reactors (BWR) is to eliminate such impurities during accidental occurrence of sea water leakage from condensate cooling system. Ion exchange resins packed in condensate demineralizer have also been expected to decrease crud, or corrosion products (CP) in condensate water in order to finally reduce activated corrosion products (ACP) in the reactor coolant loop. It is perceived that crud removal ability of a condensate demineralizer has been improved year by year. And we call this phenomenon as `Aging Effect`. Typical property changes of aged cation exchange resin consisted of an increase of waterretention capacity and a change of surface texture. Based on these findings, we formulated a new concept and developed new gel type ion exchange resins for the better crud ...
The present paper explains the curve-fitting method developed as a method to estimate the geothermal equilibrium forming temperature. In the present method, that temperature is estimated by obtaining, by non-linear lest square, the model parameter to minimize the sum of remainders squared between the temperature actually measured after a lapse of certain time from the stoppage of mud water circulation and that calculated on the basis of Middleton model, mathematical model of temperature equilibrium well. In the Horner's plotting method currently in general use, temperature recovery data during a long period of about 120h are required for estimating the geothermal equilibrium forming temperature. However in the curve-fitting method, it is confirmed from the actual well data that the well recovery temperature is estimable from three logging data during 24h after the stoppage of mud water ...
Debris coolability in the lower plenum of the reactor pressure vessel is an important factor for evaluation of debris in-vessel retention. The debris coolability analysis module is developed for the accurate prediction of the safety margin of the present reactor vessels in a severe accident. The module calculates debris spreading and cooling through melting and solidification in combination with a temperature distribution and failure evaluation of the vessel wall. Debris spreading is solved by the explicit method on a quasi-three-dimensional scheme and debris coolability is solved on the basis of natural convection analysis. The calculation for spreading is compared with a water spreading experiment on the floor and the calculation for coolability is compared with a n-octadecane melting experiment in a rectangular vessel. The comparisons show capabilities for predictions of spearhead transportation in the debris spreading process and of melting ...
Debris coolability in the lower plenum of the reactor pressure vessel is an important factor for evaluation of debris in-vessel retention. The debris coolability analysis module is developed for the accurate prediction of the safety margin of the present reactor vessels in a severe accident. The module calculates debris spreading and cooling through melting and solidification in combination with a temperature distribution and failure evaluation of the vessel wall. Debris spreading is solved by the explicit method on a quasi-three-dimensional scheme and debris coolability is solved on the basis of natural convection analysis. The calculation for spreading is compared with a water spreading experiment on the floor and the calculation for coolability is compared with a n-octadecane melting experiment in a rectangular vessel. The comparisons show capabilities for predictions of spearhead transportation in the debris spreading process and of melting ...
In this paper we review and classify the various patterns of isosteric heat versus loading for adsorption of gases on graphitised thermal carbon black at temperatures ranging from below the 3D triple point to temperatures above it, but less than the 3D critical point. We have identified the features of heat curve and highlighted the microscopic origin of these features. The patterns vary with temperature and with the relative strength of the fluid-fluid interaction and solid-fluid interaction. For simple adsorptives (by simple we meant there is no strong association between fluid particles), the heat curve is typified by fluid-fluid attraction and layering phenomena. For adsorptives showing strong association such as water, ammonia and methanol, the heat curve essentially begins below the ...
Relative doses of 75 MeV/u "1"2C ion beam after passing through different thickness of degraders were measured with the double ionization chamber method. The degrader's thickness equalized to penetration depth of the beam in water and its Bragg curve were obtained. The measured Bragg curve is compared with that calculated based on a model set up by the authors. Meanwhile, the inactivation effect of the ion beam passing through different thickness of degraders on melanoma (B_1_6) cells was measured, and the corresponding survival fraction data for B_1_6 cells were acquired
AimsThe efficacy of topical glucocorticosteroids in rhinitis and asthma is likely to depend on drug retention in the airway mucosa. With fluticasone propionate, retention may be...Full Text Available
... Accession Number : AD0749455. Title : Uptake and Retention of Adenine Moiety by Stored Human Red Blood Cells. Descriptive Note : Interim rept.,. ...
The 105-KE and 105-KW Fuel Storage Basins were constructed more than 35 years ago as repositories for irradiated fuel from the K East and K West Reactors. Currently, the basins contain irradiated fuel from the N Reactor. To continue to use the basins as desired, seismic adequacy in accordance with current US Department of Energy facility requirements must be demonstrated. The 105-KE and 105-KW Basins are reinforced concrete, belowground reservoirs with a 16-ft water depth. The entire waterretention boundary, which currently includes a portion of the adjacent reactor buildings, must be qualified for the Hanford Site design basis earthquake. The reactor building interface joints are sealed against leakage with rubber water stops. Demonstration of the seismic adequacy of these interface joints was initially identified as a key issue in the seismic qualification effort. The issue of ...
In preparation for studying the hydrolytic degradation of Estane 5703 in the plastic-bonded explosive PBX 9501, the sorption (solubility) and diffusion of water in PBX 9501 and each of its components are studied experimentally and modeled theoretically. Experiments are reported that measure the weight gain or loss due to a change in the relative humidity (RH). For all of the components, the equilibrium amount of water sorbed per gram of sample is linear in the RH at low relative humidities but curves upwards at higher relative humidities. This behavior is modeled with a water cluster model. Diffusion coefficients are determined by modeling the time dependence of the water concentrations assuming Fickian diffusion, and that fits the data for some of the materials. However, all the samples t...
Purpose Nonpoint sources (NPS) pollution has been an important cause for water quality impairment worldwide. To take the temporal variations of both NPS pollution and in-stream attenuation into consideration, an inverse modeling approach and the load duration curve (LDC) method were combined for variable nutrient total maximum daily load (TMDL) development. Methods Water quality and hydrological parameters were monitored monthly along the ChangLe River system in 2004?2008. The catchment NPS export load (EL) and TMDL for total nitrogen (TN) were estimated by the inverse format of an existing stream nutrient transport equation. The LDC method was used to describe the variability of EL, TMDL, requiring load (RLR) and percent (the ratio between the RLR and the EL, RPR) reduction, and then to s...
This paper investigates the relationship between environmental pollution and economic growth in China based on the environmental Kuznets curve hypothesis, using Chinese provincial data over 1985?2005. Waste gas, waste water and solid wastes are used as environmental indicators and GDP is used as the economic indicator. It is found by panel cointegration test that there is a long-run cointegrating relationship between the per capita emission of three pollutants and the per capita GDP. According to comparisons with the dynamic OLS estimator and the Within OLS estimator, we find that panel cointegration estimation is preferable for all pollutants except for solid wastes. The results also show that all three pollutants are inverse U-shaped, and water pollution has been improved earlier than ga...
The growth kinetics constants and concentration of active attached biomass in an anaerobic fluidized bed which decomposes acetic, propionic and butyric acid were estimated. The mixture of above mentioned fatty acids was supplied to the fluidized bed in the range of hydraulic retention time (HRT) from 0.25 to 2 days. After the effluent reached in a steady state in quality, batch experiments were conducted separately with each fatty acid as a substrate in order to investigate the decomposition characteristics of each substrate by attached biomass. In order to estimate the parameter values of the growth kinetics of the bacteria, batch experiments were also conducted under the completely mixed condition using detached biomass from a support material. The changes of fatty acid concentrations with time were clearly expressed with the Monod growth model. Maximum specific substrate decomposition rates and saturation constants, and active biomass concentrations were ...
The following paragraphs summarize the progress of each research project funded under the WVU Cooperative Agreement during the third quarter of 1997 (July - September 1997). The projects are arranged according to their 1997 WVU task number. WVU Focus Area 1.0: Subsurface Contaminants, Containment and Remediation Task No. 1.1: Project discontinued. Task No. 1.2: Development of Standard Test Protocols and Barrier Design Models for Desiccation Barriers (K. Amininan & S. Ameri): A number of experiments were preformed this period to evaluate the ability of the dried sand-packs to act as a barrier to liquids. Water infiltration tests were done with a constant head, dispersing 80 ml of water, and by adding water in small increments. Results indicate that when the water is spilled over the sand-pack, it has the tendency to channel through the sand-pack, significantly reducing the capacity of the dried zone ...
Two cases of tetracycline ulcers of the oesophagus are reported and compared with thirteen other cases from the literature. In most cases, the patients had taken their capsules with little or no fluid just before going to bed. Some hours later they developed retrosternal pain that was intensified by swallowing. Endoscopy showed sharply demarcated greyish-white areas of mucosal damage which represented layers of stratified squamous cells, separated by oedema, and a dense neutrophilic infiltration of the lamina propria and the muscularis mucosa. Roentgenology was unsuitable to detect the lesions. They healed without complications within one to six weeks. Prolonged retention of the capsules in the oesophagus is thought to cause the mucosal damage. Patients on oral tetracycline or doxycycline treatment should therefore be instructed to take their capsules with a meal or with copious water and not just before going to bed.
The main goal of this research is to delineate the wetting behavior of coal and it subsequent effects on fine coal processing. As both bulk and surface properties of coal are interrelated and have a controlling role on the performance of these processes, a detailed study has been undertaken to correlate their influence on both wetting behavior and the response of coal to flotation and other unit operations encountered in fine coal processing. During the last quarter, the effect of coal rank on waterretention capacity was investigated. The effect of pH on the vacuum flotation yield and the effect of desliming on the film flotation response of coal were also studied. 6 refs., 5 figs.
The solubility behavior of solid residues from the heat treatment of domestic rubbish was examined by simulated precipitation in laboratory lysimeters. The precipitation corresponded to the average amount of rain in West Germany and was applied at different time periods. Specific soil characteristics, the value of k/sub f/ and the waterretention capacity was determined in this way. In parallel with the lysimeter flood ions, extraction (by batch process) was done, in order to find the maximum solubility of the materials used. It was found that for pyrolysis residues from reactor temperatures of 450/sup 0/ to 1000/sup 0/C, a greater solubility was measured than for slag from combustion. The eluates from these residues gave information about the degree of contamination or on the solubility of the measured parameters and materials in organoleptic, physical, organic and inorganic examinations. The concentrations of harmful substances in the eluates ...
Several thin film composite nanofiltration membranes have been prepared by spin coating a sulfonated poly(ether ether ketone) solution on a polyethersulfone support, followed by thermal treatment. The most optimal developed nanofiltration membrane shows a clean water permeance of ~4.5Lm^-^2h^-^1bar^-^1 and a molecular weight cut off (MWCO) of ~500gmol^-^1. No irreversible changes in membrane performance have been observed after prolonged exposure (up to several weeks) of this membrane to solutions with a pH in the range 0-14. Compared to Desal-5-DK, the developed membrane displays a similar water permeance and a higher NaCl retention. In comparison to commercially available pH stable membranes, MPF-34 and NP030P, it reveals a higher water permeance. Permeance and MWCO analysis at varying p...
Because of the environmental hazard of organic solvents such as chlorinated or aromatic hydrocarbons, water soluble and biodegradable substitutes have come into use. It should be assessed how they affect soil and aquifer when spilled in leaks or accidents. This was simulated in a model system using methanol and percolation columns, one filled with material from the unsaturated subsurface and two with different materials from aquifers. The results reveal that a spill of the substitutes can also cause problems. In homogeneous soils and at long retention times until the substance reaches the aquifer, sorption and biological degradation are most likely to prevent contamination of the groundwater. When oxygen supply in the subsurface is insufficient, reducing conditions occur and sulphide is formed. The data show that much more methanol was eliminated than reflected by the consumption of electron acceptors. This indicates that sorption and anabolic ...
The long operating cycle simplified boiling water reactor is a reactor concept that pursues both safety and the economy by employing a natural circulation reactor core without a refueling, a passive decay heat removal, and an integrated building for the reactor and turbine. Throughout the entire spectrum of the design basis accident, the reactor core is kept covered by the passive emergency core cooling system. The decay heat is removed by the conventional active low-pressure residual heat removal system. As for a postulated severe accident, the suppression pool water floods the lower part of the reactor pressure vessel (RPV) in the case when core damage occurs, and the in-vessel retention that keeps the melt inside the RPV is achieved by supplying the coolant. The containment adopts a parallel-double-steel-plate structure similar to a hull structure, which contains coolant between the inner and outer walls to absorb the ...
The NUclear Power Engineering Corporation (NUPEC) has developed IMPACT-SAMPSON code to analyze integral behavior of light water nuclear power plants under severe accident conditions. IMPACT-SAMPSON's distinguishing features include interconnected hierarchical modules and mechanistic models covering a wide spectrum of scenarios ranging from normal operation to severe accident events, and high-speed simulation on parallel processing computers. The integral plant behaviors of typical PWR and BWR under severe accident conditions have been analyzed with the IMPACT-SAMPSON code. The PWR plant analyzed was the three-loop, steel-dry containment type with 2,440 MWt. The AE accident scenario was supposed, that is, LOCA by 6-inch hot leg failure followed by accumulated water injection, but no ECCS and containment spray activation. The BWR plant analyzed was the 3,293 MWt BWR-5, Mark-II containment type. The TQUV accident scenario was supposed, ...
The effect of phosphonate anion (PHOS) on the corrosion of ordinary steel in simulated cooling water has been studied using weight loss, polarization curves and electrochemical impedance spectroscopy measurements. PHOS was studied in the concentration range from 7.5x10^-^5 to 10^-^3M. The results obtained reveal that PHOS perform excellently as corrosion inhibitor for ordinary steel in simulated cooling water. The inhibition efficiency of PHOS was increased with increasing both its concentration and water circulation velocity. These two factors seem to promote the adsorption of phosphorus and oxygen ions on the metal surface, leading to the formation of a protective layer with a greater charge transfer resistance and lower permeability. The inhibition efficiency decreased slightly with tem...
The ECP of construction materials in the water steam circuits of power plants is influenced by many parameters, including: reactions of oxidants, such as O{sub 2} or dissolved copper species; and reactions of reducing species, namely N{sub 2}H{sub 4}. Electrochemical measurements were performed to clarify the role of hydrazine for the open circuit potential in water/steam circuits. Current density electrode potential curves of the electrochemical oxidation of hydrazine and the reduction of oxygen in aqueous solutions were measured as a function of temperature in the range from room temperature to approximately 260{degrees}C. The electrode materials used were platinum, gold and Alloy 800 mod.. In addition, corrosion potentials were measured in water containing oxygen or hydrazine.
The ion mobilities of |"2"1"1At|At(I) in dependence on thiourea (tu) concentration, iodide concentration and a mixture of both ligands were measured by the electromigration method in free electrolytes. An equilibrium model was developed for the characterization of electromigration curves which permitted the calculation of stability constants and ion mobilities of the complexes |AtI|, |AtI_2|"-, |Attu|"+, |Attu_2|"+ and |AtItu| existing in these solutions. Ethanol and water served as solvents. The temperature was 298 K and the ionic strength was about 0.05 mol/dm"3. (author) 16 refs.; 2 figs.
Between December 2001 and May 2004, a ventilation experiment (VE) was performed in the Mont Terri Underground Research Laboratory (URL) and co-financed by the Commission of the European Communities. The objective was to investigate the desaturation of consolidated clay formations in consequence of the ventilation of underground openings of a repository in such a formation. The results of the geoelectric measurements performed in the second phase of the Mont Terri ventilation test can be summarized as follows: Geoelectric tomography has been found suitable for monitoring ventilation-induced saturation changes in the Opalinus clay. During ventilation with dry air a desaturation down to below 50% could be detected in both desaturation cycles. The desaturated zone extends less than 0.5 m into the rock around the microtunnel. During the second resaturation phase, ventilation with humid air led to quick resaturation at the tunnel surface, while resaturation of the rock mass took months. The ...
Between December 2001 and May 2004, a ventilation experiment (VE) was performed in the Mont Terri Underground Research Laboratory (URL) and co-financed by the Commission of the European Communities. The objective was to investigate the desaturation of consolidated clay formations in consequence of the ventilation of underground openings of a repository in such a formation. The results of the geoelectric measurements performed in the second phase of the Mont Terri ventilation test can be summarized as follows: Geoelectric tomography has been found suitable for monitoring ventilation-induced saturation changes in the Opalinus clay. During ventilation with dry air a desaturation down to below 50% could be detected in both desaturation cycles. The desaturated zone extends less than 0.5 m into the rock around the microtunnel. During the second resaturation phase, ventilation with humid air led to quick resaturation at the tunnel surface, while resaturation of the rock mass took months. The ...
Purpose: Hormonal activity causes breast volume to change during the menstrual cycle. One possible cause of this volume change is thought to be due to waterretention or oedema within the tissues. We used magnetic resonance imaging (MRI) to study the variation in breast volume and {sup 1}H Magnetic Resonance Spectroscopy (MRS) to measure T{sub 2} relaxation times which are known to increase with increasing tissue water content. We hypothesised that an increase in breast volume will elevate T{sub 2} relaxation due to the presence of an increased water content within the breast. T{sub 2} Relaxation time and volume were studied in fifteen control subjects and in a cohort of eight patients with cyclical mastalgia in order to determine whether changes in breast volume and T{sub 2} relaxation times differed in controls and patients during menses, ovulation and premenses. Method: Breast volume was determined ...
More than 80% of the people of Nepal are farmers and 90% of the farmers do farming for subsistence. Agricultural productions contribute about 50% of country's GDP. Agricultural sector has been categorized as the top priority sector since many years. The environment of the country has also deteriorated substantially by the unplanned and unscientific use of natural resources such as air, soil, water, air and forest. Fertility of the soil has also been declining and studies show that productions in mountains is decreasing at a rate of 40 Kg/ha. Yr (1). The Terai, a narrow strip of land in the south, is in heavy pressure due to over exploitation and population growth (both natural and migratory). Shallow groundwater (shallow tube wells) is the main source of drinking water in Terai (the lowland region of Nepal). A study conducted by Department of Water Supply and Sewerage (DWSS) showed that more than 55% of Terai tube wells are ...
The objectives of this research were (1) to analyze the transfers of 137Cs and 60Co in a retention pond, with emphasis on aquatic insects and (2) to determine if detectable concentrations of these radionuclides are exported by emerging aquatic insects. We analyzed the radionuclide concentrations in the following components: water solution, bottom sediments, suspended particulate matter, plankton, floating mats of filamentous algae, benthic macroinvertebrates, and emerging aquatic insects. Samples were collected quarterly from June 1981 to April 1982. The lowest concentrations (in picocuries per milliliter) occurred in solution (range: 1.4 X 10(2) to 3.2 X 10(2) for 137Cs and 8.1 X 10(-1) to 2.2 X 10(0) for 60Co). The highest concentrations (in picocuries per gram dry weight) occurred in the sediments (range: 1.5 X 10(4) to 1.1 X 10(8) for 137Cs and 1.0 X 10(2) to 4.3 X 10(6) for 60Co). The primary producers and aquatic insect consumers had ...
The basic relationships of the convolution/superposition dose calculation technique are reviewed, and a modelling technique that can be used for obtaining a satisfactory beam model for a commercially available convolution/superposition-based treatment planning system is described. A fluence energy spectrum for a Co-60 treatment machine obtained from a Monte Carlo simulation was used for modelling the fluence spectrum for a Rokus M machine. In order to achieve this model we measured the depth dose distribution and the dose profiles with a Wellhofer dosimetry system. The primary fluence was iteratively modelled by comparing the computed depth dose curves and beam profiles with the depth dose curves and crossbeam profiles measured in a water phantom. The objective of beam modelling is to build a model of the primary fluence that the patient is exposed to, which can then be used for the calculation of the dose deposited in the ...
High temperature thermochemistry of thoria-urania fuel for Advanced Heavy Water Reactor was investigated. Oxygen potential development within the matrix and distribution behaviors of the fission products (fps) in different phases were worked out with the help of thermodynamic and transport properties of the fps as well as fission generated oxygen and the detailed balance of the elements. Some of the necessary data for different properties were generated in this laboratory while others were taken from literatures. Noting the behavior of poor transports of gases and volatile species in the thoria rich fuel (thoria-3 mol% urania), the evaluation shows that the fuel will generally bear higher oxygen potential right from early stage of burnup, and Mo will play vital role to buffer the potential through the formation of its oxygen rich chemical states. The problems related to the poor transport and larger retention of fission gases (Xe) and volatiles ...
A hose lining process, used widely for underground service structures, such as for city gas, and water and sewerage pipes, was adopted to repair interiors of underground wire raceways, and improvements were made for power cable pipe use, including long size construction, inner diameter assurance, and flame retardation. The sealing hose as a lining material consists of a fabric layer woven by warps of polybutylene terephthalate (PBT) and wefts of combined PBT fibers and glassfibers, the fabric being coated with polyurethane resin on one side. The other side of the fabric is coated with heat hardening resin made of epoxy resin as the main ingredient and aromatic amine as the hardening agent to assure close adhesion of the sealing hose onto the pipe interior. Mimic raceways were used to verify the lining material for its abrasion coefficient, mechanical strength, wear resistance, water cut-off performance, chemical resistance, and shape ...
The ROTAMIX process for the treatment of contaminated soils, developed by GSI Environment of Sherbrooke, Quebec, is described. The technology combines the use of a self-propelled rotary turner with bioactivating nutrients and structuring agents. Results of various trials using this process showed that soils contaminated with pentachlorophenol and heavy petroleum hydrocarbons, substances that do not easily break down, were decontaminated to a level that corresponds to the C criterion of the Quebec Ministry of the Environment. The ROTAMIX process was found to improve solid/liquid/gas exchanges, and increased waterretention capacity of the treated soil. The technology is not constrained by the fine particle concentration that may result from the addition of structuring agents. It produces no leachate water or gaseous emissions. It broadens the range of contaminants that can be treated, including contaminants that resist ...
Under the auspices of the DOE and private industry, considerable progress has been made in: preparation of coal-water fuels; combustion of low-ash coal-based fuel forms; processes to provide deeply-cleaned coal. Developments in advanced beneficiation of coal to meet stringent requirements for low ash and low sulfur can be anticipated to further complicate the problem areas associated with this product. This is attributable to the beneficiated coal being procured in very fine particles with high surface areas, modified surface characteristics, reduced particle size distribution range, and high inherent moisture. Experience in the storage, handling, and transport of highly beneficiated coal has been limited. This is understandable, as quantities of such product are only now becoming available in meaningful quantities. During this reporting period the authors have: developed a suite of empirical tests covering waterretention, ...
Crude oil-polluted soil (five parts of weathered crude oil per 100 parts of soil; equivalent to 50,000 mg oil kg{sup -}1 soil) samples were slurried in deionised water (300% of the waterretention capacity of the soil) and treated with various amounts of natural-rubber processing sludge (nitrogen content 62.15 mgkg{sup -1} and phosphorus contents 8.75 mgkg{sup -1}) in a well-stirred, continuously-aerated tank at 29{sup o}C. Changes in the total hydrocarbon content of the soil sample were determined, using a spectrophotometric technique, as a function of time. The extent of crude oil degradation was markedly higher (by up to 100%) in the sludge-treated soil than in the untreated soil sample. The efficiency of biodegradation of the crude oil hydrocarbons using the slurry-phase technique was compared with that of solid-phase technique. (author)
The thermal-hydraulic performance in periodic frosting conditions is experimentally studied for the parallel-flow parallel-fin heat exchanger, henceforth referred to as a PF{sup 2} heat exchanger, a new style of heat exchanger that uses louvered bent fins on flat tubes to enhance water drainage when the flat tubes are horizontal. Typically, it takes a few frosting/defrosting cycles to come to repeatable conditions. The criterion for the initiation of defrost and a sufficiently long defrost period are determined for the test PF{sup 2} heat exchanger and test condition. The effects of blower operation on the pressure drop, frost accumulation, waterretention, and capacity in time are compared under the conditions of 15 sequential frosting cycles. Pressure drop across the heat exchanger and overall heat transfer coefficient are quantified under frost conditions as functions of the air humidity and air face velocity. The ...
The design of high level radioactive waste (HLW) repositories in deep geological media in which bentonite clay is proposed as a sealing material leads to the need of further studying the behaviour of highly compacted expansive soils when subjected to mechanical, hydraulic and thermal changes. Laboratory tests may help to understand the processes that take place in the clay barrier under simple and controlled conditions and to develop the governing equations. The laboratory tests enable to isolate the different processes, making their interpretation easier, and provide with fundamental data concerning the parameters to be used in the models. The extremely low permeability of these materials, their avidity for water (high suction) and their high swelling capacity make necessary the modification of the conventional laboratory techniques and procedures to determine basic physical parameters. The main hydraulic properties of the barrier to be considered are the ...
The effect of sodium gluconate anion (SG) on the corrosion and scale inhibition of ordinary steel in simulated cooling water has been studied using weight loss, polarisation curves, electrochemical impedance spectroscopy (EIS) and scanning electron microscopy (SEM) techniques. SG was studied in concentration from 10{sup -4} M to 10{sup -1} M. Results obtained reveal that SG perform excellently as corrosion and scaling inhibitor for ordinary steel in simulated cooling water. An increase of SG concentration leads to the increase of the corrosion potential towards the positive direction. The inhibition efficiency was a low temperature dependence. The inhibitor mechanism was treated as an adsorption process according to Langmuir adsorption isotherm. The SEM/EDAX data show that was a corrosion and scale inhibitor.
The effect of sodium gluconate anion (SG) on the corrosion and scale inhibition of ordinary steel in simulated cooling water has been studied using weight loss, polarisation curves, electrochemical impedance spectroscopy (EIS) and scanning electron microscopy (SEM) techniques. SG was studied in concentration from 10-4M to 10-1M. Results obtained reveal that SG perform excellently as corrosion and scaling inhibitor for ordinary steel in simulated cooling water. An increase of SG concentration leads to the increase of the corrosion potential towards the positive direction. The inhibition efficiency was a low temperature dependence. The inhibitor mechanism was treated as an adsorption process according to Langmuir adsorption isotherm. The SEM/EDAX data show that was a corrosion and scale inhi...
The aim of this work was to compare dose calculation algorithm results at orthovoltage energies for a phantom composed of a bone slab in water. The calculation methods investigated were: no correction, ETAR, Batho, convolution/superposition and Monte Carlo. All algorithms calculated depth dose curves in a water phantom within 4% of experiment. However in the bone phantom, differences of over 40% between the No Correction / ETAR / Batho / Convolution and Monte Carlo results in the 1 cm thick bone slab were observed. These differences are predominantly because the algorithms do not account for the differing atomic number of the bone compared to water The increased dose to bone and the tissue adjacent to the bone interface should be considered when treating with orthovoltage photons. Copyright (1998) Australasian Physical and Engineering Sciences in Medicine
Three different magnetic regimes; aerial, surface and buried; each with three different forces, have been used to investigate their effects on the water contents and photosynthetic pigments of sweet basil plants (Ocimum basilicum L.). Two groups of sweet basil seeds, Ocimum basilicum L. have been cultivated, one under normal conditions and the second has been subdivided into three portion (aerial, surface and buried) to examine the effect of different magnetic forces coming from the three directions on the resulted plants. At all directions of magnets, water contents have been significantly affected by the magnetic forces. Chlorophyll A and carotene contents have been affected, as well, according to the three magnetic forces coming from soil surface regime only. Chlorophyll B did not significantly affected by differences magnetic forces in the three regimes, but it is affected by magnetism wherever its direction or force. But all the ...
The CASTOC project addresses environmentally assisted cracking (EAC) phenomena in low alloy steels used for pressure boundary components in both Western type boiling water reactors (BWR) and Russian type pressurised water reactors (VVER). It comprises the four work packages (WP): inter-laboratory comparison test (WP1); EAC behaviour under static load (WP2), EAC behaviour under cyclic load and load transients (WP3); evaluation of the results with regard to their relevance for components in practice (WP4). The use of sophisticated test facilities and measurement techniques for the on-line detection of crack advances have provided a more detailed understanding of the mechanisms of environmentally assisted cracking and provided quantitative data of crack growth rates as a function of loading events and time, respectively. The effect of several major parameters controlling EAC was investigated with particular emphasis on the transferability of the ...
Since microwaves are used in human cancer therapy, information on specific biological effects of microwaves at elevated temperatures is important. To help supply this information, we exposed mammalian cells (CHO) and bacteria (Serratia marcescens) to hyperthermal temperatures (43, 44, and 45/sup o/C for CHO and 48, 49, and 50/sup o/C for the bacteria) with and without microwave irradiation. Temperature control was maintained by a refrigeration-reheat system and high-velocity water recirculation. The 2450-MHz microwave source was operated in a pulsed mode with power density up to 500 mW/cm/sup 2/. As expected, the survival curve slopes for both cell types increased rapidly with temperature, doubling for each degree Celsius. Microwave irradiation produced no significant change in extrapolation number for either cell type. However, survival curves of CHO cells which received microwaves were steeper by a factor of 1.25 than ...
OBJECTIVE--To investigate the cause of post-operative retention of urine in elderly men. DESIGN--Prospective study. SETTING--Northern General Hospital, Sheffield. PATIENTS--32 consecutive men (median...Full Text Available
On the basis of soil losses records during 10 years, three levels of water erosion were established for two soil (Typical Hapludox and Oxic Dystropept) located on high and medium terraces of alluvial flat plain of piedmont in the Eastern Plains in La Libertad Research Center of CORPOICA. Eighteen 3 x 10 m"2 run-off plots were fitted out on a nonrandom arrangement of nine plots by landscape and three soil use and management treatments: zero grazing Brachiaria decumbens pasture for six years, up land rice, soybean and maize rotations for six years and bare soil for 10 years. Soil losses under these treatments allowed to define three degrees of erosion: slight (N_3 moderate (N_2) and severe (N_3) respectively. From each plot soil samples were taken at two depths for physical analyses. infiltration and resistance to cone penetration were measured in the field. Without exception water erosion produced a detrimental effect on soil physical properties ...
The SGTR project has been carried out within the fifth EURATOM Framework Programme (Contract No FIKS-CT-1999-0007). Its main objective was to provide an experimental database and to develop and/or verify models to support definition of accident management measures in the hypothetical case of a Steam Generator tube Rupture (SGTR) sequence. The project addressed both vertical and horizontal steam generator designs. This report summarises the main results obtained in the intermediate scale experimentation that addressed Western type steam generators. The specific goal of this test programme was to investigate aerosol retention in the break stage of the secondary side of a water-empty steam generator. The test matrix consisted of 12 tests that explored the influence of variables such as break type and orientation and inlet gas flow rate. This work was performed in the PECA facility of the Laboratory for Analysis of Safety Systems (LASS). Aerosol ...
According to the present concept, the low and intermediate level wastes generated during the Cernavoda NPP operation will be disposed in a near surface repository. The Saligny site, placed in the NPP protected area, has been proposed for their disposal. Geologically, the main components of this site are the quaternary loess, the Precambrian and Pre-quaternary clays, the Eocene and Barremian limestone. Hydrologically, the site can be divided into a vadose zone down to 45-50 m and three distinct aquifers, two of them in the limestone beds and the third in the lenses of sand and limestone existing in the pre-quaternary clay layer. A large research program for site characterization was initiated in 1996. At present, the site characteristics requested for safety analysis have been experimentally measured on soil samples or calculated by different computer programs. Hundreds of experimental values of the density, porosity, hydraulic conductivity, soil-water ...
The sequential layer-by-layer adsorption of polyanions and polycations to build polyelectrolyte multilayers has triggered enormous interest in their potential uses in a wide range of fields, from photonic to pharmaceutical applications. We show that the conformation of the solvent swollen films - prior to drying - is determined by the initial adsorption conditions, but can be altered ex-situ by exposure to a liquid phase of very high ionic strength. Recently it has been observed that the swelling depends on the charge of the outermost layer. In the PAH/PSS system we saw that assemblies with PSS as the outermost layer swell more than those with PAH outside. A neutron reflectivity study of this effect in addition indicated the existence of two kinds of water, bound with different strength within the films. Beside an unexpected two-step kinetics of swelling, the reflectivity curves of the layers against vacuum before and after re-hydration in ...
The interfacial tension g of the hexane solution of 1H,1H,10H,10H-perfluorodecane-1,10-diol (FC10diol) and 1H,1H,2H,2H-perfluorododecanol (TFC12OH) mixture against water was measured as a function of the total molality m and composition of TFC12OH in the mixture X2 at 298.15K under atmospheric pressure. The interfacial pressure p vs. mean area per adsorbed molecule A curves and the phase diagram of adsorption (PDA) were constructed in order to shed light on the effect of the molecular orientation on the state of and the miscibility of FC10diol and TFC12OH in the adsorbed film. The p vs. A curves demonstrated that the mixed system exhibits three kinds of film states, parallel-condensed, normal-condensed, and multilayer states, depending on m and X2. The PDA indicated that film composition X...
The concept of relative permeability is the key concept in extending Darcy's law for single phase flow through porous media to the two-phase flow regime. Relative permeability functions are needed for simulation studies of two-phase geothermal reservoirs. These are poorly known inspite of considerable theoretical and experimental investigations during the last decade. Since no conclusive results exist, many investigators use ad hoc parametrization, or adopt results obtined from flow of oil and gas (Corey, 1954). It has been shown by Reda and Eaton (1980) that this can lead to serious deficiencies. Sensitivity of the relative permeability curves for prediction of mass flow rate and flowing enthalpy into geothermal wells has been studied by many investigators (e.g. Eaton and Reda (1980), Bodvarsson et al (1980), Sun and Ershagi (1979) etc.). It can be concluded from these studies that the beehavior of a two-phase steam/water reservoir ...
This investigation presents scale-up of a detailed heterogeneous geostatistical model to a full field reservoir simulation model, considering both single and two-phase flow properties. The model represents a typical low permeability Danish North Sea chalk reservoir and includes capillary pressure and saturation end-point variations. Two new up-scaling methods has been investigated, all based on fine scale simulation on a cross section of the geomodel. The first methods assumes piston style behaviour and a coupled viscosity is introduced into the basic Darcy`s equations. The second method is a modification of the JBN method traditionally applied in analysing results from core flooding experiments, which emerged as the most successful and therefore also the recommended method. 1. In addition to the up scaling work we review the Equivalent Radius Method for capillary pressure normalisation with explicit derivation of type functions for Maastrichtian and Danian chalk types. Implementation ...
In large samples, the {gamma}-ray count rate of a prompt gamma neutron activation analysis system is a multi-variable function of the elemental dry composition, density, water content and thickness of the material. The experimental calibration curves require tremendous laboratory work, using a great number of standards with well-known compositions. Although a Monte Carlo simulation study does not avoid the experimental calibration work, it reduces the number of experimental calibration standards. This paper is part of a feasibility study for a PGNAA system for on-line continuous characterisation of cement raw material conveyed on a belt (Oliveira, C., Salgado, J. and Carvalho, F. G. (1997) Optimisation of PGNAA instrument design for cement raw materials using the MCNP code. J. Radioanal. Nucl. Chem. 216(2), 191-198; Oliveira, C., Salgado, J., Goncalves, I. F., Carvalho, F. G. and Leitao, F. (1997a) A Monte Carlo study of the influence of ...
Dams and reservoirs are among one of the most sensitive of all development Project, in terms of pervasiveness of their influence in altering the environmental conditions and resources. In the present study, major dams and reservoir projects are reviewed, from the environmental point of view. Dams and Reservoir projects bring about major changes in the immediate environment, thus affecting public health, settlements, farmlands, roads and historical sites. Impacts on human population and wildlife may be profound. Tropical diseases, involving fresh-water hosts or vectors in their transmission, are often common around new reservoirs. Large lakes create limnological changes, excessive evaporation, seepage, disturbance in water-table and increased tendencies of landslides and earthquakes. Micro climatic changes are possible, such as fog formation, increased cloudiness and modified rainfall-patterns. Retention of sediment results ...
The possibility of a positive agricultural use of flue gas filter ash from brown coal power plants is investigated. The suggested measure is mixing ash dump surfaces with extremely acidic spoil bank soils, which balances the high pH value of the alkaline ash and contributes to improved nutrient and soil sorptive conditions. Optimum quantity of spoil bank sands in the mixture with ash is between 10% and 40%. The optimum quantity must be determined for each type of ash considering improvement of soil chemical conditions and waterretention capacity. Filter ash properties vary widely; the required amount of spoil bank sand added to investigated ash surfaces near 3 brown coal power plants was between 25% and 30% of the mixture. The same favourable soil and ash mixture can be produced by adding 60% to 75% filter ash to acidic raw spoil bank soil surfaces forming a top soil layer in a thickness of minimum 60 cm. Tests of plant growth showed high crop ...
Extensive investigations have been and are being carried out on a stiff clay from an underground research laboratory located at Mol (Belgium) called Boom clay, in the context of research into deep nuclear waste disposal. Suction effects in deep Boom clay block samples were investigated through the characterisation of the waterretention and of the swelling properties of the clay. The data obtained allowed an estimation of the sample initial suction that was reasonably compatible with the in-situ state of stress at a depth of 223 m. The relationship between suction and stress changes during loading and unloading sequences were also examined by running oedometer tests with suction measurements. A rather wide range of the ratio s/sigma 'v (being s the suction and sigma 'v the effective vertical stress) was obtained (0.61 - 1), different from that proposed by Bishop et al; (1974). Finally, the effect of suction release under an isotropic stress ...
A laboratory-scale multi-layer system was developed for the adsorption of PCDD/Fs from gas streams at various operating conditions, including gas flow rate, operating temperature and water vapor content. Excellent PCDD/F removal efficiency (>99.99%) was achieved with the multi-layer design with bead-shaped activated carbons (BACs). The PCDD/F removal efficiency achieved with the first layer adsorption bed decreased as the gas flow rate was increased due to the decrease of the gas retention time. The PCDD/F concentrations measured at the outlet of the third layer adsorption bed were all lower than 0.1ng I-TEQNm-3. The PCDD/Fs desorbed from BAC were mainly lowly chlorinated congeners and the PCDD/F outlet concentrations increased as the operating temperature was increased. In addition, the r...
The ruthenium decontamination factor in Purex process falls quickly with recycles of TBP. So it is necessary to change the chemical states of RuNO complexes in order to improve DF_R_u in the uranium purification cycle. The retention of RuNO complexes in TBP-kerosenelaurohydroxamic acid is observed to be quite large in our previous work. Therefore, water-soluble short chain hydroxamic acid is used as complexing agent to decrease the distribution coefficient of Ru. Hydroxamic acid can transform RuNO complexes into in-extractable species by TBP-kerosene in certain conditions. The result of cascade experiment indicates that the ruthenium decontamination can be increased by a factor of 40-50. Acidity has more influence on the effect of pretreatment. The higher acidity is, the worse the effect will be. The pretreatment is first carried out in low acidic solution, then extractive acidity is increased. In this way, the distribution of Ru can be ...
Reduction of occupational radiation exposure dose in a BWR plant is achieved by an elimination of crud in a BWR primary loop condensate stream by condensate demineralizer. Crud removal by condensate polisher improves year by year, a phenomenon called the Aging Effect of Ion Exchange Resins. The cause of this phenomenon is assumed to be mainly due to changes in the cation resin property becoming more crud adsorptive, where a typical change in physical property of aged cation resin is an increase in waterretention capacity. Assuming that the crud removal efficiency was influenced by a crosslinkage of cation resin, an attempt was made to enhance this removal efficiency by decreasing the crosslinkage and satisfactory results were obtained. As a result, new gel type cation resins were developed with lower crosslinkage and larger surface areas, as compared with conventional gel type resins. The crosslinkage degree of these new cation resins are ...
Reduction of occupational radiation exposure dose in a BWR plant is achieved by an elimination of crud in a BWR primary loop condensate stream by condensate demineralizer. Crud removal by condensate polisher improves year by year, a phenomenon called the Aging Effect of Ion Exchange Resins. The cause of this phenomenon is assumed to be mainly due to changes in the cation resin property becoming more crud adsorptive, where a typical change in physical property of aged cation resin is an increase in waterretention capacity. Assuming that the crud removal efficiency was influenced by a crosslinkage of cation resin, an attempt was made to enhance this removal efficiency by decreasing the crosslinkage and satisfactory results were obtained. As a result, new gel type cation resins were developed with lower crosslinkage and larger surface areas, as compared with conventional gel type resins. The crosslinkage degree of these new cation resins are ...
One method of increasing juvenile fish escapement from net cod-ends is to encourage fish to approach the netting by placing an active stimulating device (ASD) in the cod-end. Two types of ASD were tested inside model cod-ends to generate variable visual stimuli. One was a free-end flag-like net panel and the other consisted of an array of free-ended ropes. Escape responses of juvenile red seabream were observed in a circulating water channel using a cod-end fitted with the ASD, and they were compared with responses to conventional polyethylene multi-ply, high-contrast cod-ends with and without ASD made from either 28- or 43-mm mesh under three light conditions. With the ASD attached, the retention rate was significantly lower, 20%, than for conventional cod-ends except in dim light with 28...
Empty palm fruit bunch fiber (EPFBF), a readily available cellulosic biomass from palm processing facilities, is investigated as a potential carbohydrate source for cellulosic ethanol production. This feedstock was pretreated using ammonia fiber expansion (AFEX) and enzymatically hydrolyzed. The best tested AFEX conditions were at 135??C, 45?min retention time, water to dry biomass loading of 1:1 (weight ratio), and ammonia to dry biomass loading of 1:1 (weight ratio). The particle size of the pretreated biomass was reduced post-AFEX. The optimized enzyme formulation consists of Accellerase (84??L/g biomass), Multifect Xylanase (31??L/g biomass), and Multifect Pectinase (24??L/g biomass). This mixture achieved close to 90% of the total maximum yield within 72?h of enzymatic hydrolysis. Fer...
The multidimensional countercurrent two-phase flow regimes that occur in a pressurized-water reactor (PWR) vessel downcomer during the refill phase of a large-break loss-of-coolant accident are studied using a transparent 1/10 scale model of a PWR vessel. The various flow regimes and their distribution in the downcomer have been identified and mapped for a range of air-water flooding experiments. The two-phase flow patterns that are identified in the downcomer included various types of film flows, droplet flows, countercurrent churn flows and cocurrent flows depending on the flooding condition. Through observation of the two-phase flow dynamics it was deduced that the physical mechanisms associated with the flooding processes could be separated into a liquid entrainment process and a film flow reversal process. In addition to the above exercise, the effect of non-uniform injection of water into the downcomer via different ...
The multidimensional countercurrent two-phase flow regimes that occur in a pressurized-water reactor (PWR) vessel downcomer during the refill phase of a large-break loss-of-coolant accident are studied using a transparent 1/10 scale model of a PWR vessel. The various flow regimes and their distribution in the downcomer have been identified and mapped for a range of air-water flooding experiments. The two-phase flow patterns that are identified in the downcomer included various types of film flows, droplet flows, countercurrent churn flows and cocurrent flows depending on the flooding condition. Through observation of the two-phase flow dynamics it was deduced that the physical mechanisms associated with the flooding processes could be separated into a liquid entrainment process and a film flow reversal process. In addition to the above exercise, the effect of non-uniform injection of water into the downcomer via different ...
SiC has been considered as a primary candidate material for a first wall component in future fusion reactor because it has been claimed that SiC has excellent high-temperature properties, good chemical stability and low activation. However, the behavior of tritium on SiC has not been discussed yet. In this study, tritium trapping capacity on the surface of SiC was experimentally obtained at the temperature range of 25-800 deg. C in consideration of tritium trapping to the experimental system. The capacity, which was independent of the water vapor pressure in the gas phase and the temperature, was determined as about 10{sup 6} Bq/cm{sup 2}. The isotope exchange reaction rate between tritiated water in a gas phase and hydrogen on the surface was quantified at the temperature of 25, 500 and 700 deg. C in consideration of the behavior of tritium trapping at change of experimental condition by the numerical curve fitting method ...
SiC has been considered as a primary candidate material for a first wall component in future fusion reactor because it has been claimed that SiC has excellent high-temperature properties, good chemical stability and low activation. However, the behavior of tritium on SiC has not been discussed yet. In this study, tritium trapping capacity on the surface of SiC was experimentally obtained at the temperature range of 25-800 deg. C in consideration of tritium trapping to the experimental system. The capacity, which was independent of the water vapor pressure in the gas phase and the temperature, was determined as about 10"6 Bq/cm"2. The isotope exchange reaction rate between tritiated water in a gas phase and hydrogen on the surface was quantified at the temperature of 25, 500 and 700 deg. C in consideration of the behavior of tritium trapping at change of experimental condition by the numerical curve fitting method applying ...
In this paper we review and classify the various patterns of isosteric heat versus loading for adsorption of gases on graphitised thermal carbon black at temperatures ranging from below the 3D triple point to temperatures above it, but less than the 3D critical point. We have identified the features of heat curve and highlighted the microscopic origin of these features. The patterns vary with temperature and with the relative strength of the fluid-fluid interaction and solid-fluid interaction. For simple adsorptives (by simple we meant there is no strong association between fluid particles), the heat curve is typified by fluid-fluid attraction and layering phenomena. For adsorptives showing strong association such as water, ammonia and methanol, the heat curve essentially begins below the condensation heat and then approaches it as loading is increased. This is mainly due to the strong hydrogen bonding ...
We have recently introduced several important improvements in the measurement of distillation curves for complex fluids. This new method is a significant improvement over current approaches, with features including a composition-explicit data channel for each distillate fraction (for both qualitative and quantitative analysis), trace chemical analysis of each distillate fraction, and a corrosivity assessment of each distillate fraction. In the present contribution, we present the application of the advanced distillation curve method to a bio-derived crude oil prepared from swine manure. One motivation behind the work was to precisely measure the distillation curve of the oil derived from swine manure with our advanced distillation apparatus and compare the bio-derived oil to traditional petroleum crude oils. Then, the information content of the bio-derived oil distillation was extended further with the composition-explicit ...
A precise admixtures system is needed when using high-volume fly ash concrete as fresh concrete occasionally undergoes rapid slump loss after mixing, which can cause problems with casting, pumping and finishing of the concrete in hot weather. This paper provided details of a study conducted to implement high-volume fly ash concrete technology in India. Different families of admixtures were investigated to determine their water reduction capacities. A set-retarding admixture was used in some of the concrete mixtures in order to determine its efficacy. An Indian Portland cement was used to create a total of 22 different concrete mixtures. Four different fly ashes were used to replace portions of the concrete. The slump of the fresh concrete mixture was monitored for 2 to 3 hours. Unit weight and temperature of the concrete was measured. Specimens were cast in steel moulds in order to determine the compressive strength and unit weight of the hardened concrete. The ...
The aim of this work is to simulate the reduction by hydrogen of the tri-uranium octo-oxide U{sub 3}O{sub 8} (obtained by uranium trioxide calcination) into uranium dioxide. The kinetics curves have been obtained by thermal gravimetric analysis, the hydrogen and steam pressures being defined. The geometrical modeling which has allowed to explain the trend of the kinetics curves and of the velocity curves is an anisotropic germination-growth modeling. The powder is supposed to be formed of spherical grains with the same radius. The germs of the new UO{sub 2} phase appear at the surface of the U{sub 3}O{sub 8} grains with a specific germination frequency. The growth reactivity is anisotropic and is very large in the tangential direction to the grains surface. Then, the uranium dioxide growths inside the grain and the limiting step is the grain surface. The variations of the growth reactivity and of the germination specific ...
Apoptosis is a pattern of cell death involving nuclear pycnosis, cytoplasmic condensation, and karyorrhexis. Apoptosis induced by continuous irradiation with gamma rays (externally given by a 137Cs source) or with beta rays (from tritiated water injected ip) was quantified in the crypts of two portions of mouse bowel, the small intestine and descending colon. The time-course change in the incidence of apoptosis after each type of radiation could be explained on the basis of the innate circadian rhythm of the cells susceptible to apoptotic death and of the excretion of tritiated water (HTO) from the body. For 6-h continuous gamma irradiation at various dose rates (0.6-480 mGy/h) and for 6 h after injection of HTO of various radioactivities (0.15-150 GBq per kg body wt), the relationships between dose and incidence of apoptosis were obtained. Survival curves were then constructed from the curves for dose ...
Computer simulated small-angle neutron scattering curves of spherical poly disperse extruded unilamellar liposomes from saturated 1,2-diacylphosphatidylcholines in the aqueous phase are evaluated by using a multi shell model, which divides the lipid bilayer of liposomes into the polar head group region, and the nonpolar hydrocarbon region consisting of the chains of methylene groups and of the region of methyl groups. In the each of these regions, the coherent neutron scattering length density is supposed to by homogeneous. The evaluation is based on obtaining of radius of gyration from Kratky-Porod plot of small-angle neutron scattering data in the Guinier region of small scattering vector values. From radii of gyration obtained at several different molar fractions N_D_2_O/(N_D-2_O + N_H_2_O) in the aqueous phase (contrasts) and independent volumetric data, the lipid surface area A_L (or the bilayer thickness d_L) and the number of water ...
We performed experimental studies on the convolution/superposition method reported in the former companion paper (Iwasaki in Radiol Phys Technol 4, 2011) using 10-MV X-ray beams from open-jaw-collimated fields. The method uses primary and scatter dose kernels formed for energy bins of X-ray spectra reconstructed as a function of off-axis distance. We made a comparison of calculations and measurements in water phantoms and thorax-like phantoms with respect to percentage depth dose curves, tissue???phantom ratio curves, and dose profiles. We made the dose calculation by taking into account the beam-hardening effect with depth and the off-axis radiation-softening effect. We found that the method could be used, in general, for performing accurate dose calculations.
Full text.Changes in land use and urbanization yield more pressure put on limited soil and water resources, including the risk of pollution with toxic heavy metals. The study area lies in the Bekaa valley totaling about 12753 ha. The valley receives from the west torrential fan deposits and a mixture of colluvial and alluvial material. The principal soil classes are Fluvisols, Cambisols, Regosols, Vertisols and Luvisols. The area is populated and also the most important agricultural part of the plain. Agriculture in the plain is being practiced mainly with cash, field crops and vegetables. The western surrounding area is being used mainly for terraced fruit trees. This Arab-German Technical Cooperation Project (ACSAD-BGR) aimed, following the ISO standards and Eikman-Klocke recommendations, at investigating the nature of the extends of soil pollution by heavy metals in two pilot areas: The central Bekaa-Lebanon and Ghouta-Damascus. Different institutions cooperate ...
An experimental investigation on the air/water counter-current two-phase flow in a horizontal rectangular channel connected to an inclined riser has been conducted. This test-section representing a model of the hot leg of a pressurized water reactor is mounted between two separators in a pressurized experimental vessel. The cross-section and length of the horizontal part of the test-section are (0.25 m x 0.05 m) and 2.59 m, respectively, whereas the inclination angle of the riser is 50 deg. The flow was captured by a high-speed camera in the bended region of the hot leg, delivering a detailed view of the stratified interface as well as of dispersed structures like bubbles and droplets. Countercurrent flow limitation (CCFL), or the onset of flooding, was found by analyzing the water levels measured in the separators. The counter-current flow limitation is defined as the maximum air mass flow rate at which the discharged ...
A new method for the preconcentration and determination of trace amounts of lead at the {mu}g/L level in natural waters has been established based on the formation of the thenoyltrifluoroacetone (TTA) complex with dibenzo-18-crown-6 (DB18C6) by means of synergistic extraction and back-extraction combined with atomic absorption spectrometry (AAS). The effect of various factors (synergism with TTA and DB18C6, shaking time, preconcentration factor, composition of the extracted species, and foreign ions etc.) on the extraction and back-extraction of lead has been investigated in detail. The lead-TTA chelate in o-dichlorobenzene forms a stable adduct with DB18C6 as Pb(TTA){sub 2} DB18C6. The stability constant ({beta}) of the adduct determined by curve fitting method was log {beta} = 4.2. The amount of lead in natural waters such as tap water (Kanazawa University) and Kakehashi river (Komatsu City) ...
Notched and smooth cylindrical plasma nitrided (PN) and quench and tempered (Q and T) steel specimens made of a B-Mn SS2131 ({approx}AISI 15B21H) steel have been exposed to constant amplitude plane reversed bending corrosion fatigue tests (R = -1) at 47 Hz in sea water. S - N curves show that sea water suppresses the fatigue limit and reduces fatigue strength (especially at long lives) of smooth and notched Q and T and PN specimens. Plasma nitriding improves the corrosion fatigue resistance of Q and T specimens; this is associated with the good corrosion resistance of {epsilon} and {gamma}`-phases, the enhancement of corrosion and fatigue by compressive residual stresses, and the consumption of H{sup +} ions during reduction of nitrogen. This improvement is more significant for smooth specimens and for long lives. Notch sensitivity of Q and T and PN specimens decreases with fatigue life. Pitting corrosion, cyclic applied ...
The stability of a solid ice cover subjected to rapidly varying water levels and discharge was investigated. The support from the bank limits the stress in the ice cover and consequently bank contact must be maintained to ensure ice cover stability. An analysis was required of the stability of ice hinges, a flexible connection between a solid ice cover and the riverbank. Phase II and phase III of the research involved a field study of the Peace River, investigating the evolution of ice hinges with water level variation, from initial ice cover cracking parallel to the banks, to a fully developed hinge. A test program of midwinter discharge variations was undertaken to gather specific data and measurements of ice hinge link length, ice thickness, hinge joint behavior, riverbank geometry, and response of ice hinging to water level variation. As a result of the program, concepts developed throughout the study were confirmed, ...
In this report we assessed retrospectively the usefulness of Thallium-201 chloride scintigraphy for diagnosing malignant tumors of the maxillofacial region. Thallium-201 chloride scintigraphy was performed on 74 patients with malignant tumors and 8 patients with benign tumors, and a retention index was calculated from the early and delayed scintigrams (delayed accumulation ratio/ early accumulation ratio). This retention index depended on the blood flow of tumors and the affinity of tumors with Thallium-201 chloride. The retention index was large for malignant tumors (avg.: 1.05) and small for benign tumors (avg.: 0.78). Concerning the degree of malignancy (the histological type and the degree of tumor involvement), the retention index was higher in highly malignant tumors (1.20 for poorly-differentiated tumors and 1.19 for aggressive-involvement-type tumors) and lower for tumors of low malignancy (1.02 ...
The deuterium inventory at JET after 2001-2004 operational campaign has been determined using nuclear reaction analysis (NRA) and secondary ion mass spectrometry (SIMS). A full poloidal set of divertor tiles and a set of outer poloidal limiter (OPL) tiles were analysed providing an estimation for the total deuterium retention of about 66 g. Deuterium is trapped mainly at the inner divertor on horizontal target tile and at the inner divertor louvre area where ?60% of the trapped D is found. The long-term D retention is ?4% of the total D input.
The prevention of subscriber churn through customer retention is a core issue of Customer Relationship Management (CRM). By minimizing customer churn a company maximizes its profit. This paper proposes a hybridized architecture to deal with customer retention problems. It does so not only through predicting churn probability but also by proposing retention policies. The architecture works in two modes: learning and usage.In the learning mode, the churn model learner seeks potential associations from the subscriber database. This historical information is used to form a churn model. This mode also calls for a policy model constructor to use the attributes identified in the churn model to divide all `churners' into distinct groups. The policy model constructor is also responsible for develop...
This study in human volunteers was designed to compare the retention of diethylenetriaminepentaacetic acid (DTPA) in the body after intravenous (i.v.) injection with that following inhalation by using a /sup 14/C labelled tracer. After i.v. injection retention in the blood could be described by three exponential components with half-times of about 1.4 min (approx. 60%). By 24 Ehr more than 99% of the /sup 14/C-DTPA had been excreted in the urine and less than 0.5% remained in the plasma. After inhalation of /sup 14/C-DTPA retention in the lungs could be represented by a single component with a half time of about 75 min. As a consequence the length of time that a therapeutically useful amount of DTPA is retained in the body is approximately twice that following intravenous injection.
Additional measurements have been made of deposition and retention of inhaled radioactively labeled iron oxide aerosols generated by a spinning top aerosol generator.
Dosimetry parameters such as deposition, clearance, retention, and translocation and dissolution of inhaled particles in and to different lung compartments may be important for the persistence of particles...Full Text Available
A case of acute urinary retention due to a vesical leiomyoma is described. This is an unusual presentation and the treatment is discussed.ImagesFull Text Available
The presence of water in export coals increases transport and handling costs. Coarse (+0.5 mm) coal constitutes the majority of the product, and small changes in its final moisture content will have a significant effect on overall product moisture. An on-line moisture monitor was installed on a product belt immediately after a coarse coal centrifuge to continuously measure the moisture content of the coal from a single centrifuge. Basic studies were also conducted with a laboratory centrifuge specifically designed to characterize various coarse coal samples in terms of their waterretention capacity. The moisture of the coarse coal (typically 6 to 9%) was found to vary by at least 1% at a particular plant, and by a number of percentage points between plants. An empirical model has been developed which can explain about 80% of the moisture variation from the 25 samples investigated. The rank of the coals ranged from 0.7 to ...
Vermicomposts as a biofertilizer can be a great option for pond manuring as they never cause any long term harm to the soil like chemical fertilizer. In this study vegetable and horticulture waste was used as an important media for vermiculture. Three separate cemented tanks (6 m{sup 3} each) were used in the system as control tank, vermicompost fertilized tank and inorganic fertilizer manured tank. Monoculture of fish was carried out with cat fish, Clarias batrachus. The produced earthworms were used as fish feed. Regular monitoring of water parameter was conducted in three different ponds. Specifically, the algal biomass variation was quite helpful in analysing the behavior of the ponds. NPK value of soil samples was analyzed intermittently to know the eutrophication level. Despite the hot summer temperature in northern part of India, which is not ideal for fish growth, we have recorded an encouraging growth performance in organic manured pond along with ...
The development of crud removal technology has started with the finding of the resin aging effect that an old ion exchange resin, aged by long year of use in the condensate demineralizer, had an enhanced crud removal capability. It was confirmed that some physical properties such as specific surface area and waterretention capacity were increased due to degradation caused by long year of contact with active oxygens in the condensate water. So, it was speculated that those degradation in the resin matrix enhanced the adsorption of crud particulate onto the resin surface, hence the crud removal capability. Based on this, crud removal resin with greater surface area was first developed. This resin has shown an excellent crud removal efficiency in an actual power plant, and the crud iron concentration in the condensate effluent was drastically reduced by this application. However, the cross-linkage of the cation resin had to ...
The development of crud removal technology has started with the finding of the resin aging effect that an old ion exchange resin, aged by long year of use in the condensate demineralizer, had an enhanced crud removal capability. It was confirmed that some physical properties such as specific surface area and waterretention capacity were increased due to degradation caused by long year of contact with active oxygens in the condensate water. So, it was speculated that those degradation in the resin matrix enhanced the adsorption of crud particulate onto the resin surface, hence the crud removal capability. Based on this, crud removal resin with greater surface area was first developed. This resin has shown an excellent crud removal efficiency in an actual power plant, and the crud iron concentration in the condensate effluent was drastically reduced by this application. However, the cross-linkage of the cation resin had to ...
The chemical thermodynamic concepts used in the calculation of solubility data of silica (quartz) are presented taking into account the PVT characteristics of water. The temperature-dependence trends between the thermodynamically calculated and the experimental quartz solubility data are very similar, but the values are widely different at high temperatures. The experimental solubility, especially along the saturation curve at high temperature and thermodynamic data for silica need to be reevaluated in order to use silica chemistry to understand geological processes. There could exist a wide range of values for silica solubility at a specified temperature, depending upon the amount of water in the reaction vessel. Thus the silica contents in geothermal fluid, in general, cannot be used as a geothermometer to estimate the reservoir temperature. The derivation of a silica geothermometer needs an extra assumption about the ...
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 changes in microstructure of a specially prepared boron nitride (BN) film as a function of film depth were studied by high resolution transmission electron microscopy (HRTEM) and other materials analysis tools. These changes were then correlated to the changes in processing parameters during film growth. The analyzed film was fabricated by the four-step ion-assisted deposition procedure known to be effective in film-stress engineering for the formation and retention of a thick cubic BN (cBN) layer with a three-step buffer-layer deposition. In this deposition, the energy of the ions assisting cBN formation was increased stepwise from 200 to 280, and then to 360 eV [S.F. Wong, C. W. Ong, G.K.H. Pang, K.Z. Baba-Kishi, W. M. Lau, J. Vac. Sci. Technol. A 22 (2004) 676]. The nominal thickness of the cBN layer was 650 nm and that for each of the three buffer layers was about 160 nm. Both the HRTEM and electron diffraction results confirmed that the top cBN layer, with ...
A study has been made of the interaction between graphitized thermal carbon-black and cyclodextrins and a series of 28 derivatives of benzene (benzene, alkyl-, isoalkyl-, dialkyl-, trialkylbenzenes, vinyl-, and allyl-benzene). The specific retention volumes form the basis for a discussion of the mechanism of interaction and drawing conclusions for the practical separation of isomeric compounds. (orig.).
The kinetics of lead distribution was studied in suckling and adult rats 8 days after a single intraperitoneal injection of "2"0"3Pb. Marked differences were observed in the kinetics of lead retention and distribution in suckling as compared to adult rats. The rate of "2"0"3Pb disappearance was lower in the whole body, blood and kidneys, but higher in the liver, while the deposition processes predominated in the brain, femur and teeth of sucklings as compared to adult animals. (auth).
We present high-quality X-ray scattering experiments on pure water taken over a temperature range of 2 to 77 C using a synchrotron beam line at the advanced light source (ALS) at Lawrence Berkeley National Laboratory. The ALS X-ray scattering intensities are qualitatively different in trend of maximum intensity over this temperature range compared to older X-ray experiments. While the common procedure is to report both the intensity curve and radial distribution function(s), the proper extraction of the real-space pair correlation functions from the experimental scattering is very difficult due to uncertainty introduced in the experimental corrections, the proper weighting of OO, OH, and HH contributions, and numerical problems of Fourier transforming truncated data in Q-space. Instead, we consider the direct calculation of X-ray scattering spectra using electron densities derived from density functional theory based on real-space ...
The two-dimensional Eulerian hydrodynamic code 2DE, with the shock initiation of heterogeneous explosive burn model called Forest Fire, is used to model numerically the interaction of jets of steel, copper, tantalum, aluminum, and water with steel, water, and explosive targets. The calculated and experimental critical condition for propagating detonation may be described by the Held V/sup 2/d expression (jet velocity squared times the jet diameter). In PBX 9502, jets initiate an overdriven detonation smaller than the critical diameter, which either fails or enlarges to greater than the critical diameter while the overdriven detonation decays to the C-J state. In PBX 9404, the jet initiates a detonation that propagates only if it is maintained by the jet for an interval sufficient to establish a stable curved detonation front. The calculated penetration velocities into explosives, initiated by a low-velocity jet, are ...
The two-dimensional Eulerian hydrodynamic code 2DE with the shock initiation of heterogeneous explosive burn model called Forest Fire, is used to model numerically the interaction of jets of steel, copper, tantalum, aluminum, and water with steel, water, and explosive targets. The calculated and experimental critical condition for propagating detonation may be described by the Held V/sup 2/d expression (jet velocity squared times the jet diameter). In PBX 9502, jets initiate an overdriven detonation smaller than the critical diameter, which either fails or enlarges to greater than the critical diameter while the overdriven detonation decays to the C-J state. In PBX 9404, the jet initiates a detonation that propagates only if it is maintained by the jet for an interval sufficient to establish a stable curved detonation front. The calculated penetration velocities into explosives, initiated by a low-velocity jet, are ...
In the paper, a fuzzy decision-making methodology is presented to decide the generation schedule of long-term hydrothermal problems with explicit recognition of statistical uncertainties in system production cost data, NO{sub x} emission data, system load demand and hydro reservoir water inflows. In deciding the optimal operation, three objectives operating cost, NO{sub x} emission and unsatisfied load demand over the whole of the planning period are simultaneously minimised. Specific technique is put forth to convert the stochastic models into their deterministic equivalents. The weighted minimax method is used to simulate the tradeoff relation between the conflicting objectives in the non-inferior domain. The fuzzy set theory is exploited to choose the best operating point over the tradeoff curve. An efficient decomposition technique is applied to reduce the complexity of the problem. In each subproblem, thermal generations are obtained by ...
During the water detritiation process most of the tritium inventory is transferred from water into the gaseous phase, then it is further enriched and finally extracted and safely stored. The control of tritium inventory is an acute issue from several points of view: - Financially - tritium is an expensive material; - Safeguard - tritium is considered as nuclear material of strategic importance; - Safety - tritium is a radioactive material: requirements for documented safety analysis report (to ensure strict limits on the total tritium allowed) and for evaluation of accident consequences associated with that inventory. Large amounts of tritium can be stored, in a very safely manner, as metal tritides. A bench-scale experiment of a tritium storage bed with integrated system for in-situ tritium inventory accountancy was designed and developed at ICSI Rm. Valcea. The calibration curve and the detection limit for this ...
Heat transfer tubes of a primary pressurized water cooled (PPWC) in the high temperature engineering test reactor (HTTR) form the reactor pressure boundary of the primary coolant, therefore are important from the viewpoint of safety. To establish inspection techniques for the heat transfer tubes of the PPWC, an automatic inspection system was developed. The system employs a bobbin coil probe, a rotating probe for eddy current testing (ECT) and a rotating probe for ultrasonic testing (UT). Nondestructive test of a half of the heat transfer tubes of the PPWC was carried out by the automatic inspection system during reactor shutdown period of the HTTR (about 55% in the maximum reactor power in this paper). The nondestructive test results showed that the maximum signal-to-noise ratio was 1.8 in ECT. Pattern and phase of Lissajous wave, which were obtained for the heat transfer tube of the PPWC, were different from those obtained for the artificially defected tube. In ...
The most relevant aspects of research and service experience with environmentally-assisted cracking (EAC) of carbon (C) and low-alloy steels (LAS) in high-temperature (HT) water are reviewed, with special emphasis on the primary pressure boundary components of boiling water reactors (BWRs). The main factors controlling the susceptibility to EAC under light water reactor (LWR) conditions are discussed with respect to crack initiation and crack growth. The adequacy and conservatism of the current BWRVIP-60 stress corrosion cracking (SCC) disposition lines (DLs), ASME III fatigue design curves, and ASME XI reference fatigue crack growth curves, as well as of the GE EAC crack growth model are evaluated in the context of recent research results. The operating experience is summarized and compared to the experimental/mechanistic background knowledge. Finally, open questions and possible ...
Finland has some 10 million hectares of peatland, accounting for almost a third of its total area. Macroclimatic conditions have varied in the course of the Holocene growth and development of this peatland, and with them the habitats of the peat-forming plants. Temperatures and moisture conditions have played a significant role in determining the dominant species of mire plants growing there at any particular time, the resulting mire types and the accumulation and deposition of plant remains to form the peat. While in a natural state the mires of Finland have functioned as carbon dioxide sinks throughout the post-glacial period, but the ditching of peatland for forestry and agriculture, amounting to some 5,7 million hectares in Finland, has affected their water balance, especially over the last hundred years, and has thereby altered the quantity and species composition of the mire vegetation. The invasion of trees and woody plants to replace the typical mire plants ...
This paper tests the Environmental Kuznets Curve hypothesis for four local (SOx, NOx, CO, VOC) and two global (CO2, GHG) air pollutants. Using a new panel data set of thirty OECD countries, the paper finds that the postulated inverted U-shaped relationship between income and pollution does not hold for all gases. A meaningful Environmental Kuznets Curve exists only for CO, VOC and NOx, where for CO2 the curve is monotonically increasing. For GHG there is indication of an inverted U-shaped relationship between income and pollution, but still most countries are on the increasing path of the curve and hence the future development of the curve is uncertain. For SOx it was found that emissions follow an U-shaped curve. Based on the empirical results, the paper concludes that the Environmental Kuznets Curve does not hold for all gases, it is ...
This paper tests the Environmental Kuznets Curve hypothesis for four local (SOx, NOx, CO, VOC) and two global (CO2, GHG) air pollutants. Using a new panel data set of thirty OECD countries, the paper finds that the postulated inverted U-shaped relationship between income and pollution does not hold for all gases. A meaningful Environmental Kuznets Curve exists only for CO, VOC and NOx, where for CO2 the curve is monotonically increasing. For GHG there is indication of an inverted U-shaped relationship between income and pollution, but still most countries are on the increasing path of the curve and hence the future development of the curve is uncertain. For SOx it was found that emissions follow an U-shaped curve. Based on the empirical results, the paper concludes that the Environmental Kuznets Curve does not hold for all gases, it is ...
curves are also directly translatable to metal-matrix composites. ..... 4~f4'4 ..... result of learning curve. The most important reduction in cost as a ...
The measuring series was performed from November 1991 through April 1992 in seven drinking-water conditioning plants of the Fichtel mountains area in the north-eastern part of Bavaria, and the results revealed as an annual average a dose of about 1 - 40 WLM. The area of interest is a drinking-water catchment area where the ground water and other water resources include waters particularly rich in radon content, which explains this relatively high dose range. This is why comprehensive, specific local and long-term mearurements were carried out in order to assess the occupational radiation dose in the drinking-water conditioning plants, taking as a model site the conditioning plant of the municipal utilities of Hof in Weissenstadt. These more specific measurements were performed by the Technical Inspectorates (TUeV) of Bavaria and Saxony and the isotope laboratory ...
As wastewater travels through a sewer system it undergoes changes in composition. The changes in composition may be caused by chemical, physical and/or biological processes. At present engineers do not take into consideration the impacts of these processes on the wastewater quality when designing wastewater treatment systems. However, the impact of these processes on the chemical oxygen demand, biochemical oxygen demand, nitrogen and phosphorus content of the wastewater can be significant. In the case of the biological processes, microorganisms present in the water as it travels through the sewer system are similar to those found in an activated sludge process. Given that the microorganism population and the hydraulic retention time often resembles that of an activated sludge process, it would seem only reasonable to look further into the possibility of using sewers as wastewater treatment systems. Furthermore, the plug flow regime of a ...
As a result of the large limestone deposits available in Poland, the low cost of reagent acquisition for the largescale technological use and relatively well-documented processes of flue gas desulfurization (FGD) technologies based on limestone sorbent slurry, wet scrubbing desulfurization is a method of choice in Poland for flue gas treatment in energy production facilities, including power plants and industrial systems. The efficiency of FGD using the above method depends on several technological and kinetic parameters, particularly on the pH value of the sorbent (i.e., ground limestone suspended in water). Consequently, many studies in Poland and abroad address the impact of various parameters on the pH value of the sorbent suspension, such as the average diameter of sorbent particles (related to the limestone pulverization degree), sorbent quality (in terms of pure calcium carbonate [CaCO3] content of the sorbent material), stoichiometric surfeit of CaCO3 in ...
This conference provided a forum for more than 500 delegates from industry, government universities and research centres to share their professional knowledge on research and development that affects all sectors of geotechnical engineering, applied geology and hydrogeology. Accomplishments in the geoenvironmental field were also highlighted. The geotechnical sessions were entitled: pile foundations and load testing; excavations and special foundation issues; reinforced soil and soil-structure interactions; advances in modelling, constitutive issues; advances in modelling, consolidation and other applications; advances in modelling, discrete elements and slope stability; embankments and dams; landfills and barriers; fundamental soil mechanics; soil mechanics and ground movement; GIS and remote sensing; landslides and slopes; cone penetration tests and liquefaction assessment; rock mechanics; engineering geology; geoenvironmental sustainability; oilsand and petroleum geomechanics; and, ...
A preliminary geologic investigation was conducted to determine if Triassic sedimentary rocks of the Sanford basin and Colon cross structure in North Carolina are favorable hosts for uranium deposits. Rocks of adjacent Carolina slate belt were also examined as a potential source of uranium. On the basis of favorability criteria for sandstone-type uranium deposits, and geologic and geophysical investigations of the study area, the most favorable sites for further investigation are (1) at the contacts between the Pekin and Cumnock and between the Pekin and Sanford Formations near the Colon cross structure and (2) at the base of the Jonesboro fault, which lies below the Sanford Formation, northwest of Sanford. The highly weathered granites southeast of the Jonesboro fault were a source of the detritus deposited on the cross structure and may have been a primary source of uranium. Uranium leached from the coarse sediment (Pekin Formation) of the cross structure may have been transported ...
Nitrogen metabolism and protozoa production rate using "1"4C-choline as marker were studied on 9 adult male crossbred (Tharparker x Brown Swiss) rumen fistulated animals divided into 3 groups (A, B and C). All the animals were fed concentrate mixture and wheatstraw. However, groundnut cake (GNC) in concentrate mixture was untreated in group A, 50 per cent formaldehyde treated in group B and 100 per cent formaldehyde treated in group C. Although, DM intake was similar in these groups but water intake was significantly (P<0.05) higher in control group. Total-N, ammonia-N and blood urea were significantly lower in group B and C as compared to group A. Apparent CP digestibility was not affected by addition of formaldehyde treated GNC at 50 and 100 per cent levels. However, N balances increased significantly (P<0.05) due to addition of protected protein in diet. Protozoal pool as well as production rate were significantly (P<0.01) decreased due to formaldehyde ...
The dominant shrubs were sagebrush and spiny hopsage; the herbs were dominated by cheatgrass and Sandberg bluegrass. Spiny hopsage appeared to be vulnerable to burning and also to damage by off-road vehicular traffic. It appears to have little or no ability to reproduce through seedlings; once the existing plants are killed they are not likely to be replaced, even if seed-producing plants are nearby. The only pure stand of spiny hopsage known to exist on the Hanford Site is on and near study plot 2H. Sagebrush, like spiny hopsage, is killed by burning and by heavy vehicles. Sagebrush is capable of reproducing via seeds, indicating that it is an inherently aggressive species with a capacity to reestablish itself if parent plants are in the vicinity to act as seed sources. Alien, annual plants, especially cheatgrass, were a major contributor to the herbaceous canopy cover in plots 3S, 4S, and 5S. However, native perennial grasses, especially Sandberg bluegrass, were a major contributor ...
The germination and growth of Pinus radials Don. plantlets in solid residues deriving from a Kraft pulp industry was evaluated. Plant conditions were monitored by histological studies of roots and shoot-tips, as well as by plant analyses of several essential and non essential elements. The solids employed consisted of ashes, fly-ashes, dregs, grits, primary sludge, brown stock screening rejects and various mixtures of them. Their addition, in a range of combinations to sandy/metamorphic or marine terrace/clay soils, resulted in effective and sustained growth under greenhouse conditions. Low proportions of wastes favored growth in most cases, indicating that they may act as fertilisers. In some experiments, especially in those where waste was added in proportions ranging from 50% to 60%, germination and/or development were slightly affected. Two-year old field experiments have confirmed that in spite of the high pH values, Na ion content or elevated water ...
The Phebus FP project in an international reactor safety project. Its main objective is to study the release, transport and retention of fission products in a severe accident of a Light Water Reactor (LWR). The FPT4 test was performed with a fuel debris bed geometry, to look at late phase core degradation and the releases of low volatile fission products and actinides. Post Test Analyses results indicate that releases of noble gases (Xe, Kr) and high-volatile fission products (Cs, I) were nearly complete and comparable to those obtained during Phebus tests performed with a fuel bundle geometry (FPT1, FPT2). Volatile fission products such as Mo, Te, Rb, Sb were released significantly as in previous tests. Ba integral release was greater than that observed during FPT1. Release of Ru was comparable to that observed during FPT1 and FPT2. As in other Phebus tests, the Ru distribution suggests Ru volatilization followed by fast redeposition in the ...
The Four years of the IMPACT, 'Integrated Modular Plant Analysis and Computing Technology' project Phase 1 have been completed. The verification study of Severe Accident Analysis Code SAMPSON prototype developed in Phase 1 was conducted in two steps. First, each analysis module was run independently and analysis results were compared and verified against separate-effect test data with good results. Test data are as follows: CORA-13 (FZK) for the Core Heat-up Module; VI-3 of HI/VI Test (ORNL) for the FP Release from Fuel Module; KROTOS-37 (JRC-ISPRA) for the Molten Core Relocation Module; Water Spread Test (UCSB) for the Debris Spreading Model and Benard's Melting Test for Natural Convection Model in the Debris Cooling Module; Hydrogen Burning Test (NUPEC) for the Ex-Vessel Thermal Hydraulics Module; PREMIX, PM10 (FZK) for the Steam Explosion Module; and SWISS-2 (SNL) for the Debris-Concrete Interaction Module. Second, with the Simulation Supervisory System, up to ...
Prostate and cervical cancer patients are often treated with external X-ray beams of bi-lateral incidence. Such treatment may incur some dose effect that cannot be predicted precisely in commercial treatment planning systems (TPS) for patients having undergone total hip replacement. This study performs a Monte Carlo (MC) simulation and an analytical calculation (convolution superposition algorithm which is implemented in ADAC TPS) of a 6 MV, 5x5 cm"2 X-ray beam incident into water with the existence of hip prosthesis, e.g. Ti6Al4V and CoCrMo alloy. The results indicate that ADAC TPS cannot precisely account for the scatter and backscatter radiation that a metal hip prosthesis causes. For percent depth dose (PDD) curves, the maximum underdosage of ADAC TPS up to 5 mm above the interface between dense material and water is 5%, 20% and 27% for PDD_B_o_n_e, PDD_T_i and PDD_C_o, respectively. The dose re-buildup, which occurs ...
Spectral absorption properties of total suspended matter (TSM) and colored dissolved organic matter (CDOM) are important for the use of the bio-optical model to estimate water quality parameters. This study aims to investigate the variation in the absorption coefficients of TSM and CDOM of inland waters. A total of 92 water samples were collected from Shitoukoumen Reservoir and Songhua Lake in Northeast China, analyzed for TSM and Chl-a, and measured for the absorption coefficient of TSM, CDOM and total pigments using a laboratory spectrophotometer. The absorption coefficient of TSM has been decomposed for phytoplankton and inorganic sediments. The results show that for Shitoukoumen Reservoir, CDOM has strong absorptions with shallow absorption slopes (i.e., the coefficient S in a(?)=a(?0)exp[-S(?- ?0)]) and large absorption at 355 nm; and for Songhua Lake, CDOM follows similar spectral absorption ...
Whole-body retention and excretion following a single oral dose of radiolabeled lead (/sup 203/Pb) in chronically lead-exposed pregnant BK:W mice were examined over 10-13 days. This was compared with values in similarly treated nonpregnant females and in ip injected females. Whole-body and bone retention were greater in injected than in orally dosed nonpregnant females; gastrointestinal absorption was estimated from this difference. Whole-body retention in the pups was measured at birth and at the end of the experiment. Whole-body retentions in pregnant females and in their pups at birth were significantly raised after treatment at Gestational Day 17, but not after treatment at Gestational Day 11, 14, 20, 23, or 26. Pup body burdens at birth were significantly and positively correlated with maternal retention. Measurement of radioactivity in bone, kidney, brain, heart, and liver of ...
Whole-body retention and excretion following a single oral dose of radiolabeled lead ("2"0"3Pb) in chronically lead-exposed pregnant BK:W mice were examined over 10-13 days. This was compared with values in similarly treated nonpregnant females and in ip injected females. Whole-body and bone retention were greater in injected than in orally dosed nonpregnant females; gastrointestinal absorption was estimated from this difference. Whole-body retention in the pups was measured at birth and at the end of the experiment. Whole-body retentions in pregnant females and in their pups at birth were significantly raised after treatment at Gestational Day 17, but not after treatment at Gestational Day 11, 14, 20, 23, or 26. Pup body burdens at birth were significantly and positively correlated with maternal retention. Measurement of radioactivity in bone, kidney, brain, heart, and liver of ...
[sup 203]Pb-chloride is a promising imaging agent for tumour scanning because of the large retention value for tumour tissue and the small value for normal organs, but the large value for the kidneys and bone is a shortcoming. The retention value of [sup 203]Pb in tumour tissue is larger than that of [sup 201]Tl and smaller than that of [sup 67]Ga. The tumour/inflammatory lesion retention ratio for [sup 203]Pb is very large in comparison with those for [sup 67]Ga and [sup 201]Tl. [sup 203]Pb accumulates to a large extent in viable tumour tissue, and less in necrotic tumour tissue and in inflammatory lesion. (author).
The US National Council on Radiation Protection and Measurements, in collaboration with the International Commission on Radiological Protection, has been developing a biokinetic and dosimetric model for radionuclide-contaminated wounds. The finalised model is described briefly in this paper, together with the scientific basis and application. The multicompartment model uses first-order linear biokinetics to describe the retention and clearance of a radionuclide deposited in a wound site using seven default retention categories. Examples using plutonium nitrate in colloidal form and uranium in metal fragments show the behaviour of the less soluble forms of radionuclides in wounds, in which long-term retention is predicted. Using uranium as an example, the wound model is coupled to a uranium International Commission on Radiological Protection systemic model to predict urinary excretion patterns for different physicochemical ...
Using data on libraries collected by the Association of Research Libraries (ARL) and the Association of College and Research Libraries (ACRL), as well as fall-to-fall retention rates obtained from the Integrated Postsecondary Education Data System (IPEDS) of the National Center for Education Statistics (NCES), this study employs statistical measures of association to analyze the relationship of both library expenditures and number of professional library staff to student persistence. The strongest relationships found were those between student retention and total library expenditures, total library materials costs, and serial costs for institutions categorized as baccalaureate colleges within the Carnegie Classification System. The most significant relationship between persistence and numb...
On efficient glass capillary columns packed with graphitized thermal carbon black (GTCB) the stereoisomers of aromatic and saturated tricyclic hydrocarbons are completely separated and identified. The Henry's adsorption constants of the individual isomers were determined from mixture at different temperatures. Five isomers of perhydroanthracene, five isomers of perhydrofluorene, two isomers of perhydrophenalene, four isomers of perhydroacenaphthene, as well as phenalene, dihydrophenalene, acenaphthene and acenaphthylene were investigated. The increase of the hydrogenization degree of unsaturated tricyclic hydrocarbons reduces the retention. Among the saturated tricyclic isomers the retention becomes shorter with the larger bending of the molecules, i.e. from the molecule having more equatorial bonds to the molecules having more axial connections. The experimentally determined Henry's constants were qualitatively compared with ...
The Rio Grande alluvial floodplain aquifer between El Paso/Juarez and Fort Quitman, Texas has been intensively tilled and irrigated since 1910. Almost since that time, the Rio Grande and its interconnected alluvial aquifer in this stream reach have been affected by excessive salinity problems. Presently, salinity of surface water and groundwater increases from 800 to 2000 mg/L total dissolved solids (TDS) near El Paso, Texas to 2500 to 5500 mg/L TDS near Fort Quitman, Texas, approximately 115 km downstream. Chloride (Cl) and Chloride/Bromide (Cl/Br) ratios increase downstream, with a marked increase in salinity beginning about 45 km below El Paso. Groundwater sampling in an intensively investigated reach of the floodplain aquifer, extending from 35 to 60 km below El Paso identified two distinct water types. The first water type (17 samples) is a relatively dilute groundwater containing 1000 to 2000 mg/L TDS, 250 to 600 ...
The true potential energy curve for the x "1#SIGMA#"+ state of BeO has been calculated using the RKRV method. The dissociation energy of the ground state has been estimated to be 5.15 +- 0.05 eV by the curve-fitting method using the three-parameter potential energy function of Lippincott with an RKRV potential energy curve. (author).
In this paper we present an approximation method for the convolution of two planar curves using pairs of compatible cubic B?zier curves with linear normals (LN). We characterize the necessary and sufficient conditions for two compatible cubic B?zier LN curves with the same linear normal map to exist. Using this characterization, we obtain the cubic spline approximation of the convolution curve. As illustration, we apply our method to the approximation of a font where the letters are constructed as the Minkowski sum of two planar curves. We also present numerical results using our approximation method for offset curves and compare our method to previous results.
The retention indices of cycloalkenes and cycloalkadienes with C/sub 6/-C/sub 13/ rings are determined by gas-liquid chromatography (GLC) on glass capillary columns coated with OV-1 and Ucon LB 550X and by gas-solid chromatrography (GSC) on a microcolumn packed with uncoated graphitized thermal carbon black (GTCB). Structure-retention correlations are derived on using index differences such as H/sup OV/, H/sup GTCB/ and ..delta..I values, considering the differences in the stereochemistry of these compounds. It is shown that the combined application of index increments obtained in GLC and GSC provides more detaled structure informations. The value of the retention index units agree with the most stable conformations of the alicyclic compounds. The high value for the energy equivalent to an index unit (..delta..G/sub I.U./ = 4.18 kJ/mol) confirms that graphitized thermal carbon black causes much stronger dispersive ...
ObjectivesTo examine the strength of the volume–outcome relationship among paramedics, a group of providers that has not been previously studied in this context. By identifying...Full Text Available
This human investigation of lead absorption from the lungs utilized two forms of lead, lead chloride and lead hydroxide; the former was used in picogram amounts and the latter at microgram levels. These two species of lead were selected in an attempt to simulate the range of physicochemical properties found in atmospheric lead (urban air). Aerosols labeled with lead-203 were made of comparable aerodynamic size by using sodium chloride as the deposition-determining aerosol. After brief, mouthpiece exposures, 17 subjects were followed by serial counting with a thoracic array of scintillation detectors and two leg counters. Serial blood samples were also taken. The two exposure groups showed similar total deposition values (23 vs 26%) and the same biological retention halftimes, viz., 22.6 hr. When the retention data were corrected for blood-borne /sup 203/Pb, the biological halftimes for lung lead retention averaged 13.1 and ...
Mucopolysaccharidosis type IIIB (MPS IIIB; Sanfilippo syndrome type B) is a metabolic disorder with devastating clinical characteristics starting in early childhood and leading to premature death. A...Full Text Available
In the past, the fermentation activity of Saccharomyces cerevisiae in substrates with a high concentration of sucrose (HSuc), such as sweet bread doughs, has been linked inversely to invertase activity...Full Text Available
2,3-Dimercaptosuccinic acid (DMSA) is a new orally active heavy metal chelator for the treatment of childhood Pb intoxication on an outpatient basis. The influence of DMSA, as well as other chelating agents, on gastrointestinal 203Pb absorption and whole-body "2"0"3Pb retention was examined. Groups of Sprague-Dawley rats (230-260 g) were gavaged with a solution containing approximately 25 mg/kg Pb [as Pb(NO_3)2] plus 15 microCi "2"0"3Pb. Some groups were then immediately given 0.11 mmol/kg of either DMSA, CaNa2EDTA, D-penicillamine, or BAL by oral gavage, while other groups received the same drugs by ip injection. Control groups received solutions of the drug vehicles po or ip. Whole-body Pb retention and gastrointestinal Pb absorption (whole body retention + urinary Pb excretion) were significantly decreased in rats that received DMSA po. This finding implies that the use of DMSA to treat childhood lead intoxication on an ...
Single doses of lead (trace to 445 mg/kg) were administered per os to suckling and adult mice. Both groups exhibited dose-independent lead retention when doses of 4 to 445 mg/kg were administered. However, developmental differences in the fraction of initial dose (FID) retained were evident for all doses administered. A much larger FID was retained in both age groups following administration of carrier-free /sup 203/Pb. The results are consistent with a mechanism of gastrointestinal lead absorption comprising two or more processes. Developmental differences were also observed in organ lead concentration relative to whole body concentration for kidneys, skull and brain 6 days following lead administration. Lead retentions (relative to whole body retention) in brain and in bone were linearly related to dose of lead administered in both suckling and adult age groups. Though uptake of lead into brain and into femur was observed ...
A review of the literature on chronic inhalation studies in which rats were exposed to mineral fibres at known fibre number concentrations was undertaken to examine the specific roles of fibre length...Full Text Available
A type of electromyographic activity, formerly referred to as "pseudomyotonia", can be recorded from the striated muscle of the urethral sphincter using a concentric needle electrode. There are two...Full Text Available
BackgroundPlastid genome content and protein sequence are highly conserved across land plants and their closest algal relatives. Parasitic plants, which obtain some or all of their...Full Text Available
This paper describes the development of an interactive internet-based cost-estimating tool for commonly used urban storm runoff best management practices (BMP), including: retention and detention ponds, grassed swales, and constructed wetlands. The paper presents the cost data, c...
The Specific Methanogenic Activity (SMA) and sludge biodegradability of an anaerobic sludge depends on various operational and environmental conditions imposed to the anaerobic reactor. However, the effects of hydraulic retention time (HRT), influent COD concentration (COD_inf) and sludge retention time (SRT) on those two parameters need to be elucidated. This knowledge about SMA can provide insights about the capacity of the UASB reactors to withstand organic and hydraulic shock loads, whereas the biodegradability gives information necessary for final disposal of the sludge. (Author)
The doctorate in Counselor Education and Supervision is the terminal degree in the field of counselor education within the U.S. The authors surveyed CACREP-accredited doctoral programs to assess department characteristics, clinical experience and credentials, research experience, and the admission, retention, and evaluation of students. Results indicated that the PhD was a preferable degree to other degree offerings. Programs were found to be diverse in their policies and procedures relating to admissions and retention, time to complete the program, and student expectations. International students and faculty representation was found to be sparse in CACREP-doctoral programs. Implications for future research and practice are offered.
Four /sup 125/I labeled mono- and diamines were prepared and evaluated as potential brain-imaging agents. The diamines are analogues of the previously reported /sup 75/Se labeled diamines, which show high brain uptake and retention. All of the radioiodinated amines display high initial brain uptake in rats after intravenous injection (1.7-2.4% dose/organ). The xylylenediamines show prolonged brain retention (t1/2 approximately 18 h), which is desirable for brain imaging. In contrast, the benzylamine is rapidly cleared from brain tissue (t1/2 approximately 15 min).
The oral administration of 2,3-dihydroxybenzoic acid (DHB) to rats injected intravenously 1 hr previously with "2"3"9Pu citrate caused an increase in urinary excretion of Pu about 8 times that of animals treated with 0.9% NaCl (controls). Liver retention of Pu was decreased from 18% at 2 days in the control animals to 11% in DHB-treated rats. The skeletal retention was similarly reduced from 56% in the control group to 40% in the DHB-treated animals.
Adult and newborn rats were exposed to "2"3"9PuO_2 aerosols of four different size distributions. Rats of both ages were killed at intervals between 1 hr and 60 days postexposure. There were marked age- and particle-related size differences in deposition, although retention was similar throughout. The differences in deposition are attributable to relatively greater deposition of larger particles in the upper respiratory tracts of newborns.
In light water reactors, austenitic stainless steels (SSs) are used extensively as structural alloys in reactor core internal components because of their high strength, ductility, and fracture toughness. However, exposure to high levels of neutron irradiation for extended periods degrades the fracture properties of these steels by changing the material microstructure (e.g., radiation hardening) and microchemistry (e.g., radiation-induced segregation). Experimental data are presented on the fracture toughness and crack growth rates (CGRs) of wrought and cast austenitic SSs, including weld heat-affected-zone materials, that were irradiated to fluence levels as high as {approx} 2x 10{sup 21} n/cm{sup 2} (E > 1 MeV) ({approx} 3 dpa) in a light water reactor at 288-300 C. The results are compared with the data available in the literature. The effects of material composition, irradiation dose, and water chemistry on CGRs ...
This thesis was carried out at Forsmark Nuclear Power Plant. The power plant in Forsmark consists of three boiling water reactors (BWR) which produce about 17% of Swedish electricity. In a BWR the nuclear reactions are used to boil water inside the reactor vessel. The water works both as a coolant and as a moderator and the resulting steam is used directly to run the turbines. A problem when running a BWR at low flow conditions is the density wave oscillations that might occur to the water flow inside the fuel assemblies. These oscillations arise due to the connection between power and flow rate in a heated channel with two-phase flow. In order to improve the stability performance of the channel an orifice plate is placed at the inlet of each fuel assembly. Today these orifice plates have sharp edges and a constant resistance coefficient. Experimental work has been done with progressive orifices, the ...
Precondition for the low-NO operation of gas turbine burners is the generation of as homogeneous as possible a gaseous fuel/air mixture. Such a burner behavior can be achieved by selective adaptation of the flow and injection. A computing model is introduced that calculates the dynamically balanced GASs/droplet flow through numerical solution of the transport equations in a curved orthogonal coordinate system. The feedback reaction of the fuel droplets to the gas phase is considered by source terms and/or sink terms. Test computations were carried out for comparison with analytical solutions from the flow mechanics and validated by comparison with measurement results. Droplet motion and evaporation were checked by means of published experimental results on single droplets. For the validation of the developed computing technique, model tests were carried out with water in place of fuel. It is pointed out that the choice of different parameters ...
New comparative tests on two different types of solar collectors are presented in this paper. A standard glazed flat plate collector and an evacuated tube collector are installed in parallel and tested at the same working conditions; the evacuated collector is a direct flow through type with external compound parabolic concentrator (CPC) reflectors. Efficiency in steady-state and quasi-dynamic conditions is measured following the standard and it is compared with the input/output curves measured for the whole day. The first purpose of the present work is the comparison of results in steady-state and quasi-dynamic test methods both for flat plate and evacuated tube collectors. Besides this, the objective is to characterize and to compare the daily energy performance of these two types of collectors. An effective mean for describing and analyzing the daily performance is the so called input/output diagram, in which the collected solar energy is plotted against the ...
Oxygenated sterol compounds (OSC), when incubated for 1 hr with human erythrocytes in lipoprotein-depleted medium at concentrations of 0.625-5 x 10/sup -5/M, are inserted into the cell membrane and remain there despite subsequent washing of the cells. The insertion results in expansion of the surface area of the red cell ghost membrane, an increase in critical hemolytic volume, and as a consequence, in dimished osmotic fragility of the erythrocytes. This effect is seen with echinocyte-forming as well as with non-echinocyte-forming OSC. Erythrocytes treated with OSC do not differ from control cells with respect to their mean cell volume (MCV) in isotonic solution, water content, ion fluxes, and filterability through polycarbonate filters. The shift of the osmotic fragility curve toward lower NaCl concentrations is proportional to the amount of OSC inserted into the red cell membrane. 7BETA-Hydroxycholesterol, 22-ketocholesterol, and 20 ..cap ...
Two-phase pressure drop and fluctuating static pressures were measured in a small horizontal rectangular channel (hydraulic diameter = 5.44 mm). The two-phase fluid was an air/water mixture at atmospheric pressure tested over a mass flux range of 50 to 2,000 kg/m[sup 2] [center dot] s. Two-phase flow patterns were identified and an objective method was found for determining the flow pattern transition from bubble or plug flow to slug flow. The method is based on an RMS static pressure measurement. In particular, it is shown that the transition is accompanied by a clear and abrupt increase in the RMS pressure when plotted as a function of mass quality. Use of the RMS pressure as a two-phase flow pattern transition indicator is shown to have advantages over pressure-versus-time trace evaluations reported in the literature. The transition is substantiated by a clear local change in slope in the curve of two-phase pressure drop plotted as a ...
The reinforced concrete artificial iced course, constructed first in Japan as a bobsleigh and luge track for the Nagano Olympic Games, has a total extension of 1,700 m and an altitude difference of 113 m. It contains 15 curves and 2 up-grades and is divided into 43 blocks with spans ranging from 20 m to 80 m, all of which consist of lightwall RC members supported by pile foundations. The surface is cooled to -15 centigrade by the cooling pipes embedded in concrete and is iced by spraying water, and iced surface is shaved to make a course. Since the course scarcely has same profiles, the finished wall thickness is secured by fixing wire gauzes on the required positions without using shutterings. As there is not existed concrete satisfying all the required quality, two kinds of concrete were selected for filling in the arrangement of reinforcement and pipes and for surface finishing. Special notice was taken of the accuracy of finished surface. ...
In this paper, we report on the analysis of reverse flow in inverted U-tubes of a steam generator under natural circulation condition. The mechanism of reverse flow in inverted U-tubes of the steam generator with natural circulation is graphically analyzed by using the full-range characteristic curve of parallel U-tubes. The mathematical model and numerical calculation method for analyzing the reverse flow in inverted U-tubes of the steam generator with natural circulation have been developed. The reverse flow in an inverted U-tube steam generator of a simulated pressurized water reactor with natural circulation in analyzed. Through the calculation, the mass flow rates of normal and reverse flows in individual U-tubes are obtained. The predicted sharp drop of the fluid temperature in the inlet plenum of the steam generator due to reverse flow agrees very well with the experimental data. This indicates that the developed mathematical model and ...
The objective was to estimate oral Al bioavailability from tea infusion in the rat, using the tracer 26Al. 26Al citrate was injected into tea leaves. An infusion was prepared from the dried leaves and given intra-gastrically to rats which received concurrent intravenous 27Al infusion. Oral Al bioavailability (F) was calculated from the area under the 26Al, compared to 27Al, serum concentrationxtime curves. Bioavailability from tea averaged 0.37%; not significantly different from water (F=0.3%), or basic sodium aluminum phosphate (SALP) in cheese (F=0.1-0.3%), but greater than acidic SALP in a biscuit (F=0.1%). Time to maximum serum 26Al concentration was 1.25, 1.5, 8 and 4.8h, respectively. These results of oral Al bioavailabilityxdaily consumption by the human suggest tea can provide a si...
An historic Strontianite-type specimen from Strontian, Scotland, UK, was characterized to broaden our knowledge on luminescence properties of common carbonates. These fibrous aggregates are Strontianite (Sr{sub x}Ca{sub 1-x}CO{sub 3}) with circa 6% of CaO, interfacial water, hydrosilicate anions and substitutional divalent cations, e.g., Ca{sup 2+}, Mn{sup 2+}, Fe{sup 2+} in structural Sr{sup 2+} positions. The specimen was analyzed by X-ray Fluorescence Spectrometry (XRF), Environmental Scanning Electron Microscopy coupled with an Energy Dispersive X-ray Spectroscopy (ESEM-EDS) probe, Spatially-resolved Cathodoluminescence under the Scanning Electron Microscope (SEM-CL), Differential-Thermal Analyses (DTA), Thermogravimetry (TG), Thermoluminescence (TL), Radioluminescence (RL) and High Resolution Spectra Thermoluminescence (3DTL), to gain an overview of the spectral emissions, the defect linkages were modified by heating from room temperature (RT) up to 500 deg. ...
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Myocardial time-activity curves can be described by two or more parameters. To establish the optimal curve fitting method 33 myocardial time-activity curves were analyzed with different curve fitting methods: monoexponential, biexponential and monoexponential plus constant. A background correction was not applied. Biexponential curve fitting resulted in redundancy of parameters. Optimal curve fitting was obtained with monoexponential plus constant. The constant represents the background activity together with the stores radiolabelled lipids and the half-time value represents the wash-out of radioiodide from the myocardium. A strong relation was found between the constant and the half-time value: small errors in the determination of the constant (background activity) resulted in considerable errors of the half-time value. It is concluded that optimal analysis of ...
It is expected that the progressive increase of tropospheric trace gases such as CO{sub 2} and O{sub 3} will have a significant impact on agricultural production. The single and combined effects of CO{sub 2} enrichment and tropospheric O{sub 3} on grain quality characteristics in soft red winter wheat (Triticum aestivum L.) were examined in field studies using 3 m in diam. open-top chambers. Wheat cultivars {open_quotes}Massey{close_quotes} (1991) and {open_quotes}Saluda{close_quotes} (1992) were exposed to two CO{sub 2} concentrations (350 vs. 500 {mu}mol CO{sub 2} mol{sup {minus}1}; 12 h d{sup {minus}1}) in combination with two O{sub 3} regimes (charcoal-filtered air vs. ambient air + 40 {plus_minus} 20 nmol O{sub 3} mol{sup {minus}1}, 7 h d{sup {minus}1}; Monday to Friday) from late March until maturity in June. Grain quality characteristics investigated included: test weight, milling and baking quality, flour yield, protein content, softness equivalent, alkaline ...
The leaching of phosphorus (P), nitrogen (N), and radionuclides "2"3"2Th, "2"2"6Ra, "2"2"8Ra, and "4"0K from Joel sands amended with red mud/gypsum (RMG) at 9 rates (0, 2, 4, 8, 16, 32, 64, 128, and 256 t/ha) was measured using columns. Intense leaching conditions (34 mm/day for 12 days) and a high rate of applied P (320 kg/ha as superphosphate) and N (680 kg/ha as ammonium nitrate) were used to simulate extremes of irrigated vegetable production on the Swan Coastal Plain. Addition of the highest rate of RMG (256 t/ha) reduced leaching of fertiliser P and ammonium-nitrogen (NH4-N) by 85% and 50%, respectively, compared with 0 t/ha after 12 days. At 64 t RMG/ha P leaching was reduced 50% compared with 0 t/ha. Nitrate-nitrogen (NO3-N) leaching was not affected by addition of RMG. Reduced leaching of NH4-N was attributed to an increase in cation exchange capacity of the soil with the addition of RMG. Bicarbonate-extractable P in the soil increased with rate of RMG to >50 #mu#g P/g soil ...
X-ray diffraction enhanced imaging (DEI) is applied to inspect internal structures of weakly absorbing low-Z sample. How to extract phase information from raw images measured in different positions of rocking curve is the key problem of DEI. In this paper, we present an effective extraction method called polynomial curve fitting method, in order to extract accurate information angular in a fast speed. It is com- pared with the existing methods such as multiple-images statistical method and Gaussian curve fitting method. The experiments results on a plastic cylinder and a black ant at the Beijing Synchrotron Radiation Facility prove that the polynomial curve fitting method can obtain most approximate refraction-angle values and its computation speed is 10 times faster than the Gaussian curve fitting method. (authors)
The Kyoto Protocol attempts through political negotiations to guide participating industrialized countries' greenhouse gas (GHG) emissions from a positive growing trend, to reach a peak point (or turning point), and then be reduced to a negative growth. That means the relationship between decreasing GHG emissions and economic growth may be described by an inverted-U curve (or called a bell-shaped curve), which is consistent with the concept of the Environmental Kuznets Curve (EKC) hypothesis.This research observed that the economic development and GHG emissions in Economies in Transition (EITs) exhibit a hockey-stick curve trend (or called quasi-L-shape curve), that also generates a lot of "hot air" which is significant to the implementation of the Kyoto Protocol. In addition, through the ...
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... The main goal was the analysis of the Environmental Kuznets Curve hypothesis for the Czech Republic. A paper by Bruha and Scasny, accepted to the European Society of Ecological Economics, ( Lisbon June 2005), analyses driving forces (including economic policy) on ...
The parameters including knot numbers, knot positions and the weights associated with the systematic errors in the cubic spline curve fitting method were discussed. The conditions of using fitting criterion were given as well.
An unexpectedly high probability of collisions between the fission particles and the atoms in an ionization chamber along the entire particle track causes a strong fluctuation of the shapes of the Bragg curves. This fluctuation imposes an upper limit of the charge resolution ..delta..Z/Z which can be achieved.
BackgroundThe receiver operating characteristic (ROC) curve is a fundamental tool to assess the discriminant performance for not only a single marker but also a score function combining...Full Text Available
The tendency of welded joints from 10Kh14AG15 and 10Kh14AG9 steels to pitting corrosion under the conditions of operating blast-furnace gas purification scrubbers has been investigated. Water in scrubbers contains various quantities of chlorides and sulfates, has pH from 6 to 9 and temperature 65-75 deg. The laboratory corrosion tests have been carried out also on samples turned from the heat-affected zone (h.a.z.) of welded plates at 20 and 65 deg. Anode polarization curves have been read from the Vk corrosion potential at potential shifting rate 0.01 V/min. It is established that in most rigid conditions of scrubbers operating pitting corrosion (PC) rate of chrome-manganese nitrogen-containing steel can reach 2.5 mm/year. At high content of chlorides in water the elevated temperature and external tensile stresses intensify PC. The resistance of welded joints to PC when using welding materials on chromonickel molybdenum ...
In July 2005 a new algorithm was released by Varian Medical Systems for the Eclipse planning system and installed in our institute. It is the anisotropic analytical algorithm (AAA) for photon dose calculations, a convolution/superposition model for the first time implemented in a Varian planning system. It was therefore necessary to perform validation studies at different levels with a wide investigation approach. To validate the basic performances of the AAA, a detailed analysis of data computed by the AAA configuration algorithm was carried out and data were compared against measurements. To better appraise the performance of AAA and the capability of its configuration to tailor machine-specific characteristics, data obtained from the pencil beam convolution (PBC) algorithm implemented in Eclipse were also added in the comparison. Since the purpose of the paper is to address the basic performances of the AAA and of its configuration procedures, only data relative to measurements in ...
This article introduces a predictive capability for Hg retention in any Ca-based wet flue gas desulfurization (FGD) scrubber, given mercury (Hg) speciation at the FGD inlet, the flue gas composition, and the sulphur dioxide (SO2) capture efficiency. A preliminary statistical analysis of data from 17 full-scale wet FGDs connects flue gas compositions, the extents of Hg oxidation at FGD inlets, and Hg retention efficiencies. These connections clearly signal that solution chemistry within the FGD determines Hg retention. A more thorough analysis based on thermochemical equilibrium yields highly accurate predictions for total Hg retention with no parameter adjustments. For the most reliable data, the predictions were within measurement uncertainties for both limestone and Mg/lime systems operating in both forced and natural oxidation mode. With the U.S. Environmental Protection Agency's (EPA) Information ...
Up to now the retention of radioactive material for nuclear facilities has been based on the maximum individual dose. The maximum individual dose can locally be lowered considerably by higher dissolution. In general, the collective doses are not lowered by this. In order to set up regulations concerning collective doses, the new recommmendations of the ICRP are very welcome. However, the costs of detriment and the period to be considered have not yet been defined. Therefore there are no fixed methods for carrying out a cost-benefit analysis. Furthermore, for nuclear technology the costs and the effectiveness of the retention of radioactive material for non-realized facilities can only be quoted roughly, which makes a cost-benefit analysis more difficult. A cost-benefit analysis for the retention of radioactive material in nuclear power plants with LWRs and reprocessing plants of the PUREX process has been carried out with ...
Production decline-curve analysis is accepted for prediction of future performance of oil and gas wells and fields. One type of decline-curve analysis involves the hyperbolic-decline-curve equation. The challenge with this equation is to determine simultaneously three parameters. The new method creates a computer spreadsheet containing a set of production data. Then, the specific arrangement of cells and columns containing data and/or formulas allows for statistical fits of the data. Finally, setting-up the nonlinear solver allows for optimization of the three parameters by maximization of the square of the regression coefficient. Eight field cases demonstrated the repeatable and rapid curve-fitting of the method.
In reservoir fluid flow, the situation described by an increase in nonwetting phase saturation followed by an increase in wetting phase saturation causes a relative permeability hysteresis effect that is well known. This paper presents a method which allows the calculation of imbibition relative permeability starting at any saturation. The data required are the drainage curve, the historical maximum non wetting saturation, and a minimum of one additional point on some corresponding experimental imbibition curve. In this development, all imbibition curves are shown to be parallel. Also significant is the fact that the residual nonwetting phase saturation can be calculated without a complete experimental specification of the imbibition curve. 5 refs.
A new method for determining the energy gap of a superconductor using the maximum in the differential conductance curve of electron tunneling spectrum is given in this paper. The V/sub max//kT versus ..delta../kT curve was calculated from tunneling theory. V/sub max/, the voltage of the conductance maximum, can be measured from electron tunneling spectrum. ..delta../kT can be found from this curve, then the energy gap ..delta.. can be calculated. This method is simple, fast and accurate. The accuracy almost approaches that of the curve fitting method.
This largely expository paper first gives an introduction to Hilbert stability and its use in Gieseker's GIT construction of $\\overline{M}_g$. Then I review recent work in this area--variants for unpointed curves that arise in Hassett's log minimal model program, starting with Schubert's moduli space of pseudostable curves, and constructions for weighted pointed stable curves and for pointed stable maps due to Swinarski and to Baldwin and Swinarski respectively. The focus is on the steps at which new ideas are needed. Finally, I list open problems in the area, particularly some arising in the log minimal model program that seem inaccessible to current techniques.
Efficiency calibration curves for different densities and geometries are necessary for activity determination of various environmental samples. Commercially available standards or natural radioactive materials are used for calibration. Potassium compounds are especially suitable, since they can be mixed with unknown samples. It is possible to determine efficiency curve and unknown activity of sample knowing "4"0 K activity. (author).
A new method named 'Bragg curve spectroscopy', based on the Bragg curve of the heavy ion being stopped in a gaseous ionization chamber, has been developed for identifying the particle and measuring its energy. The design of such a chamber and the experience obtained with chamber using various kinds of fast heavy ions are described. In conclusion, several problems to be solved in this method are pointed out.
A new method named 'Bragg curve spectroscopy', based on the Bragg curve of the heavy ion being stopped in a gaseous ionization chamber, has been developed for identifying the particle and measuring its energy. The design of such a chamber and the experience obtained with chamber using various kinds of fast heavy ions are described. In conclusion, several problems to be solved in this method are pointed out. (orig.).
The corrosion behavior of steel in water from certain oil fields with various organic inhibitors was studied by applying potentiodynamic technique at pH 5.9. The inhibitors which were used include 2-methylbenzimidazole (I), 2-mercaptobenzimidazole (II), 2-mercapto-5-methylbenzimidazole (III), and 2-mercaptothiazole (IV). The inhibiting efficiency of the different additives was evaluated from their anodic and cathodic polarization curves at different temperatures. A comparative study of curve fitting procedures using the kinetic thermodynamic model and those utilizing well-known adsorption isotherms was undertaken. Three types of isotherms were used, Langmuir, Frumkin and Flory-Huggins isotherm. The results show that the kinetic-thermodynamic model and Flory-Huggins isotherms are more suitable to fit the data for the four inhibitors, at all applied temperatures. From the values of binding constants, K, the order of inhibitor ...
The interest in radioiodinated diamines stems from their similarity to /sup 125/I-HIPDM and to the 1-dialkvlamino-acyl-4-phenylpiperazines that the authors have previously examined as potential brain imaging agents. In this study they converted the 1-(dialkylaminoacyl)-4-phenylpiperazines to their corresponding 1-(dialkylaminoacyl) analogs via reduction with diborane in THF. Radioiodination at the no-carrier-added level with Na/sup 125/I and chloramine-T gave the final compounds, after chromatographic separation, in 30-50% yields. The tissue distributions were determined in rats at 0.25, and 4 hrs after an i.v. injection of the radiochemical. The results indicated that all of the agents were readily extracted by the brain (1.5-2.5% ID) with brain to blood ratios >20. The structure-distribution relationships for this series were, however, decidedly different from the aminoacyl compounds in that morpholino-derivatives had better uptake and retention than the ...
The interest in radioiodinated diamines stems from their similarity to /sup 125/I-HIPDM and to the 1-dialkvlamino-acyl-4-phenylpiperazines that the authors have previously examined as potential brain imaging agents. In this study they converted the 1-(dialkylaminoacyl)-4-phenylpiperazines to their corresponding 1-(dialkylaminoacyl) analogs via reduction with diborane in THF. Radioiodination at the no-carrier-added level with Na/sup 125/I and chloramine-T gave the final compounds, after chromatographic separation, in 30-50% yields. The tissue distributions were determined in rats at 0.25, and 4 hrs after an i.v. injection of the radiochemical. The results indicated that all of the agents were readily extracted by the brain (1.5-2.5% ID) with brain to blood ratios >20. The structure-distribution relationships for this series were, however, decidedly different from the aminoacyl compounds in that morpholino-derivatives had better uptake and retention than the ...
Three inclined tubular digesters of 13- to 15-litre volume were operated at temperatures between 20 and 30 degrees C with hydraulic retention times of 10-15 days on pig slurry of 10%, 5% and 2.5% Total Solids content. Tube inclination of 16-20 degrees gave no scumming problems. Solids were retained, giving improved gas yields when compared with literature values for conventional stirred digesters. Solids retention is affected by the size of the digester exit and appears to be greater with slurry of low solids content. There is a link between the movement of solids and gas along, and out of, the digester which can lead to unstable oscillating gas production. Tracer studies showed soluble components of the slurry mixed throughout the whole volume of the digester in 25% of the hydraulic retention time or less. Solids moved in well dispersed plug flow. Gas production (both intrinsic and after the addition of acetate) was most ...
In developing new Tc-99m brain perfusion imaging agents for SPECT, a series of BAT (bis-aminoethanethiol) derivatives was prepared. These N/sub 2/S/sub 2/ ligands formed stable and neutral complexes with reduced Tc-99m, either by Sn(II)-PPi or sodium borohydride reduction. The purity of the Tc-99m complexes was >95% (HPLC reverse-phase column, acetonitrile: pH 7.0 buffer, 85:15). The biodistribution in rats was evaluated using I-125 iodoantipyrine (IAP), a free diffusible tracer, as the internal reference. Compounds with a free hydroxyl group (I and IV) showed lower brain uptake, inspite of high P.C.; this may be related to in vivo instability of the complexes. High initial brain uptake was observed for three compounds (II, III and V), however, only compound V (P.C.=384) showed significant brain retention. Planar imaging with compound V in a monkey demonstrated that the compound localized in brain and the retention time was T/sub 1/2/=35 ...
In developing new Tc-99m brain perfusion imaging agents for SPECT, a series of BAT (bis-aminoethanethiol) derivatives was prepared. These N/sub 2/S/sub 2/ ligands formed stable and neutral complexes with reduced Tc-99m, either by Sn(II)-PPi or sodium borohydride reduction. The purity of the Tc-99m complexes was >95% (HPLC reverse-phase column, acetonitrile: pH 7.0 buffer, 85:15). The biodistribution in rats was evaluated using I-125 iodoantipyrine (IAP), a free diffusible tracer, as the internal reference. Compounds with a free hydroxyl group (I and IV) showed lower brain uptake, inspite of high P.C.; this may be related to in vivo instability of the complexes. High initial brain uptake was observed for three compounds (II, III and V), however, only compound V (P.C.=384) showed significant brain retention. Planar imaging with compound V in a monkey demonstrated that the compound localized in brain and the retention time was T/sub 1/2/=35 ...
Retention and/or reincorporation of plant residues increases soil organic nitrogen (N) levels over the long-term is associated with increased crop yields. There is still uncertainty, however, about the interaction between crop residue (straw) retention and N fertilizer rates and sources. The objective of the study was to assess the influence of straw management (straw removed [SRem] and straw retained [SRet]), N fertilizer rate (0, 25, 50 and 75kgNha^-^1) and N source (urea and polymer-coated urea [called ESN]) under conventional tillage on seed yield, straw yield, total N uptake in seed+straw and N balance sheet. Field experiments with barley monoculture (1983-1996), and wheat/barley-canola-triticale-pea rotation (1997-2009) were conducted on two contrasting soil types (Gray Luvisol [Typi...
The fabrication and complete evaluation are described of a dihydropyridine in equilibrium pyridinium salt type redox system for the delivery of radioiodinated agents to the brain. The pivotal intermediate, N-succinimidyl (1-methylpyridinium iodide)-3-carboxylate was prepared by condensation of nicotinic acid and N-hydroxysuccinimide in the presence of dicyclohexylcarbodimide, followed by quaternization of III with methyl iodide. Tissue distribution studies of "1"2"5I-labeled 4-iodoaniline and the redox agents were performed in rats. ["1"2"5I]Iodoaniline initially showed moderate (0.58% dose/gm) brain uptake with subsequent release of the radioactivity from the brain. ["1"2"5I]Iodoaniline, when coupled to a dihydropyridine carrier showed higher uptake and retention in the brain. The ["1"2"5I]iodophenylethyl analogue showed uptake and retention in the brain to be very similar. Apparently the lipophilic agents cross the blood-brain barrier and are ...
The random walk function is a mathematical function derived from studies of the mass transport and flow of diffusible materials through tubes. Approximations to the function were first used some time ago in the field of cardiac tracer dilution curves, but in the absence of rapid and reproducible curve fitting the method never became commonplace. The current study uses the latest curve-fitting techniques and shows how the method may be used with precision in the analysis of time-activity curves from dynamic oesophageal and blood flow studies. The physiological basis of the method is given and parameters obtained which relate to both the rate of flow and the local dispersion of the bolus.
In this effort, the nonlinear responses and stability of a spindle system supported by ball bearings are presented. The dynamics of this system is described by a set of second order differential equations with a nonlinear piecewise smooth force. The Floquet theory is applied to investigate the stability of the periodic solution. Due to the loss of contact between the raceways and balls in the ball bearing, the bending of the frequency response curves switch to the left at the weak resonance region, which is similar to the frequency response curves of a system with a soft spring. With the decrease of the bearing clearance, the bending of the frequency response curves switch to the right, which is similar to the frequency response curves of a system with a hard spring. Increase of the frequency ratio, the bending of frequency response curves transforms from left to right. The route to ...
The present invention concerns a method of evaluating corrosion resistance of a zirconium alloy easily and in a short period of time. An anode polarization curve of the zirconium alloy is measured to obtain an anode polarization curve expressed by logarithm. The curve is converted to a potential-current density curve expressed by absolute values. The peak area in the curve of the converted potential-current density is indicated by numerical values. Further, the corrosion resistance of the zirconium alloy is evaluated based on the peak area converted into the numerical values as a reference. This method is based on the finding that the peak area has a close relation with nodular corrosion resistance, and the corrosion resistance can be judged with respect to a specific zircaloy-2. (T.M.).
An alternative utilization is presented for the gaseous ionization chamber in the detection of energetic heavy ions, which is called Bragg Curve Spectroscopy (BCS). Conceptually, BCS involves using the maximum data available from the Bragg curve of the stopping heavy ion (HI) for purposes of identifying the particle and measuring its energy. A detector has been designed that measures the Bragg curve with high precision. From the Bragg curve the range from the length of the track, the total energy from the integral of the specific ionization over the track, the dE/dx from the specific ionization at the beginning of the track, and the Bragg peak from the maximum of the specific ionization of the HI are determined. This last signal measures the atomic number, Z, of the HI unambiguously.
Thermoluminescence (TL) properties of sphene and epidote are of interest in studies related to their radiation damage. Natural and artificially induced TL of these minerals has, therefore, been investigated. Both minerals exhibit complex glow curves with several overlapping peaks. The Tsub(m) -Tsub(STOP) thermal cleaning procedure has revealed three peaks in the ..gamma.. ray induced glow curve of each mineral. That these peaks obey second order kinetics was indicated by the continuously slanting structure of the Tsub(m)-Tsub(STOP) curve. The TL parameters E and s have been calculated using (i) the initial rise method, and (ii) the glow-peak shape method. In general, the values of E calculated by the first method are found to be higher than those from the second. The TL curve-fitting method is also applied in order to calculate these parameters and to serve as a cross-check on the results.
In view of no satisfactory mathematical model is presently available for the dose-response curve of immunoradiometric assay, a three parameter model based on single binding site mass action law has been derived. A curve fitting method based on similar principle of linear robust regression was designed and a software was prepared for use on IBM personal computers. Experiments revealed that the model is applicable to a variety of IRMA systems as well as to time-resolved immunofluorometric assay of hAFP. When there was outlier(s) of the calibration curve, the average bias of unknown samples obtained with this method is significantly smaller than methods using four parameter logistic model or four parameter single site mass action model.
The thermodynamic characteristics of sorption of the isomeric tricyclo[5.2.1.02.6]decane (tetrahydrodicyclopentadiene, TDCPD) molecules were for the first time determined experimentally and by molecular statistical methods under the conditions of gas-adsorption chromatography on graphitized thermal carbon black and gas-liquid chromatography on stationary liquid phases of different polarities (Apiezon L and Carbowax 20M). The effects of the chemical nature of sorbents on the retention of the TDCPD isomers are considered. A procedure for calculating the thermodynamic characteristics of adsorption of molecules with a complex structure is suggested within the framework of the atom-atom approximation of the semiempirical molecular statistical theory of adsorption for the example of isostructura...
This paper outlines an approach to develop estimates of individual customer contestability using a combined statistical and engineering analysis. The approach is targeted for use for mid-size commercial and industrial customers who are not being considered for individual flexible pricing contracts. Contestability is defined as the potential lost revenue associated with customers leaving the utility or significantly reducing electricity purchases. Contestability is modeled from the customer`s perspective using a two-stage decision process. In the first stage, the customer decides if he will continue to purchase electricity from the utility (referred to as customer retention), and in the second stage, the customer determines the amount of electricity purchased (referred to as load retention). Measures of individual customer contestability will be key factors in developing market segments and new rate offerings in future energy markets.
Four "1"2"5I labeled mono- and diamines were prepared and evaluated as potential brain-imaging agents. The diamines are analogues of the previously reported "7"5Se labeled diamines, which show high brain uptake and retention. All of the radioiodinated amines display high initial brain uptake in rats after intravenous injection (1.7-2.4% dose/organ). The xylylenediamines show prolonged brain retention (t1/2 approximately 18 h), which is desirable for brain imaging. In contrast, the benzylamine is rapidly cleared from brain tissue (t1/2 approximately 15 min).
In developing new brain imaging agents for single photon emission computed tomography (SPECT), we synthesized eleven radioiodinated phenoxyacetic acid derivatives and investigated the relationship between the chemical structure and in vivo characteristics. Biodistribution studies in mice revealed high initial brain uptake for all the compounds. Blood radioactivity level depended markedly upon the chemical stability of the compound. The alpha,alpha-dimethylester derivative, amide derivatives and diamine derivatives, which were stable to hydrolysis, showed low blood activity levels following intravenous administration. Disappearance of the ester and amide compounds from the brain was rapid. However, the diamine derivatives displayed improved retention in the brain. Compounds 3a and 4 possessed the best combination of high brain uptake and sufficient retention to be useful as potential brain imaging radiopharmaceuticals with SPECT devices.
The separation and the mechanism of retention of ion associates of #alpha#-isomers of molybdic and tungstic heteropoly acids (HPA) of phosphorus(5), silicon(4), and germanium(4) with trioctylamine (TOA) on a column (80x3 mm) packed with Diasorb-130-CN (8 #mu#m) were studied in a flow of chloroform-tetrahydrofuran (THF) and chloroform-n-butanol-TOA mixtures with spectrophotometric detection at 320 nm. It is demonstrated that the adsorption of all the studied ion associates proceeds through the displacement THF molecule from the surface of the stationary phase and without the displacement of TOA molecules. Conditions for the separation of phospho- and silicomolybdic HPA and also phospho- and germanolybdic HPA were found. The chromatographic system using silica gel modified with nitrile groups as the stationary phase is of higher selective than that using ummodified silica gel.
Experiments have been reported previously in which lead-212 ions with lead carrier were instilled into the lungs of anaesthetised rabbits. Experiments were also reported in which bismuth-207 chloride was instilled into rabbit lung. To check that the chloride compound was cleared in the same way as ions instilled in isolation, lead-203 chloride has been instilled in three rabbits. Measurements of absorption of ionic lead have been repeated using the radon-222 daughter, lead-214. Rates of clearance from the lung of "2"0"3Pb as the chloride and "2"1"2Pb ions are compared, and retention functions are derived. Clearance from the lung of "2"1"4Pb ions is also shown, and retention functions are derived. (U.K.).
The thermoluminescence (TL), blue stimulated luminescence (BSL) and infrared stimulated luminescence (IRSL) signals of fluorapatite (originating from Durango, Mexico) were measured and found to exhibit strong anomalous fading (AF). The experimentally obtained OSL and IRSL decay curves were transformed into pseudo-linear modulated (pseudo-LM) decay curves. The resulting glow-curve shaped pseudo-LM decay curves were analyzed using a deconvolution analysis, similar to the one used for the glow-curve deconvolution (GCD) of TL glow-curves. It was found that the pseudo-LM OSL and IRSL decay curves consist of two components named fast and slow, respectively, and their individual contribution was estimated. The AF of the remnant TL, BSL and IRSL as a function of the storage time was fitted using the tunneling model equations and the fading rate g, ...
The thermoluminescence (TL), blue stimulated luminescence (BSL) and infrared stimulated luminescence (IRSL) signals of fluorapatite (originating from Durango, Mexico) were measured and found to exhibit strong anomalous fading (AF). The experimentally obtained OSL and IRSL decay curves were transformed into pseudo-linear modulated (pseudo-LM) decay curves. The resulting glow-curve shaped pseudo-LM decay curves were analyzed using a deconvolution analysis, similar to the one used for the glow-curve deconvolution (GCD) of TL glow-curves. It was found that the pseudo-LM OSL and IRSL decay curves consist of two components named fast and slow, respectively, and their individual contribution was estimated. The AF of the remnant TL, BSL and IRSL as a function of the storage time was fitted using the tunneling model equations and the fading rate g, ...
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The objective of this project was to develop new photocatalytic or other innovative process chemistry for the treatment of pink water and related contaminated water.
Macrocephaly was defined as a head measuring larger than 98th percentile. We have evaluated CT findings and head growth curves in 25 infants with large heads. Ten (40%) of 25 infants with large heads were normal developmentally and neurologically. Five (20%) of those were mentally retarded. The other 10 infants (40%) included hydrocephalus (4 cases), malformation syndrome (3 cases), brain tumor (1 case), metabolic disorder (1 case) and degenerative disorder (1 case). Their head growth curves were typed as (I), (II) and (III): Type (I) (excessive head growth curve to 2 SDs above normal); Type (II) (head growth curve gradually approached to 2 SDs above normal); Type (III) (head growth curve parallel to 2 SDs above normal). Ten of macrocephaly with normal psychomotor development were studied clinically and radiologically in details. They were all male. CT pictures of those showed ...
The thermodynamic characteristics of adsorption on the surface of graphitized thermal carbon black at 300 K were determined by the molecular statistical method for three phenylalklylamines. The influence of the intramolecular H-bond on the conformation of the molecules compared with structurally related n-alkyl-benzenes was considered. It was shown that the conformations of the molecules could influence chromatographic retention. Conformational isomers stabilized by intramolecular H-bonds were found to retain their structure in adsorption on graphitized thermal carbon black.
The thermodynamic characteristics of adsorption on the surface of graphitized thermal carbon black at 300 K were determined by the molecular statistical method for three phenylalklylamines. The influence of the intramolecular H-bond on the conformation of the molecules compared with structurally related n-alkyl-benzenes was considered. It was shown that the conformations of the molecules could influence chromatographic retention. Conformational isomers stabilized by intramolecular H-bonds were found to retain their structure in adsorption on graphitized thermal carbon black.
Retention or dispersion of larvae from the spawning grounds has been identified as one of the key processes influencing recruitment success in fish stocks. To examine the potential effects of transport on recruitment. numerical simulations were performed utilizing a three-dimensional physical oceanographic model of the Baltic Sea. Cod larvae were represented as Lagrangian drifters released in the deepwater region of the Bornholm Basin, the main spawning ground for Baltic cod. Simulations were performed for the major spawning seasons of 1993 and 1994. when annual and interannual variability of meteorological forcing was large. The principal goals of the modelling exercise were first to identify the physical processes influencing the demersal distribution of the early life stages and second to describe the transport of the pelagic stages in response to variations in windstress, thereby identifying the meteorological and hydrodynamic mechanisms influencing ...
Introduction:Exposure to secondhand smoke causes premature death and disease in non-smokers and indoor smoke-free policies have become increasingly prevalent worldwide. Although...Full Text Available
Cycling parameters (reversible specific capacity, first-cycle coulombic efficiency, accumulated irreversible capacity, and reversible capacity retention) of hybrid electrodes based on mechanical mixtures of a silicon nanopowder with KS6 and MAG-20 synthetic graphites and binders of varied nature were subjected to an integrated analysis in comparison with graphite electrodes.
Addresses factors affecting rural education in Tasmania (Australia), including population trends, financial support, student enrollment, socioeconomic status of rural residents, and geographic isolation. Issues that need to be addressed include the status of small schools in Tasmania, costs associated with transporting students, staffing, low student retention, and limited availability of special services. (LP)
The synthesis, characterization of M"vO([CH_3CH_2N(CH_2CH_2S)_2](p-S-Ph-COOCH_2-CH_3)) (M:"9"9"mTc: I, Re: II) is presented in this work, where a pendant ester function is attached to the monothiolate ligand. Chemical structure of I is established after chromatographic comparison with II, synthesized in macroscopic amounts. Complex II is fully characterized by classical methods of analysis showing that the compound adopts a distorted trigonal bipyramidal configuration around the metal. The two sulfur atoms of the tridentate ligand and the oxo group form the basal plane, while the remaining nitrogen atom of the tridentate ligand and the sulfur atom of the monothiolate ligand occupy the apices of the bipyramid. In vitro challenge experiments with glutathione (GSH) in neutral aqueous medium demonstrate, that I suffers nucleophilic attack by GSH and thereby transformation to a more hydrophilic daughter metal compound. Formation of the latter depends on time and GSH concentration. Tissue ...
This human investigation of lead absorption from the lungs utilized two forms of lead, lead chloride and lead hydroxide; the former was used in picogram amounts and the latter at microgram levels. These two species of lead were selected in an attempt to simulate the range of physicochemical properties found in atmospheric lead (urban air). Aerosols labeled with lead-203 were made of comparable aerodynamic size (MMAD 0.25 ..mu..m +- 0.1) by using sodium chloride as the deposition-determining aerosol. After brief, mouthpiece exposures, 17 subjects were followed by serial counting with a thoracic array of 12 2-in. scintillation detectors and two 2-in. leg counters, all coupled to single channel analyzers. Serial blood samples were also taken. The two exposure groups showed similar total deposition values (23 vs 26%) and the same biological retention halftimes, viz., 22.6 h. When the retention data were corrected for blood-borne /sup 203/Pb, the ...
The research project for which this is the final report was initiated in 1977 with the following three major objectives: Assess the retention potential for spilled oil within the coastal environments of Alaska's Beaufort Sea; Characterize the morphology and sediments of the Beaufort coast; Determine, as precisely as possible, the annual longshore sediment transport rate.
We report the oxygen, hydrogen, and deuterium effects on nitrogen implantation of stainless steel. Oxygen is absorbed on the surface creating a potential barrier and diminishing the nitrogen retention. Deuterium removes more oxygen from the surface than hydrogen, augmenting the nitrogen chemical potential and yielding faster nitrogen diffusion into the bulk material.
This paper reviews the effects of neutron irradiation on thermal and mechanical properties and bulk tritium retention of armour materials (beryllium, tungsten and carbon). For each material, the main properties affected by neutron irradiation are described and the specific tests of neutron irradiated armour materials under thermal shock and disruption conditions are summarized. Based on current knowledge, the expected thermal and structural performance of neutron irradiated armour materials in the ITER plasma facing components are analysed.
From the alkalised crude extract of Symphytum cordatum (L.) W.K. roots, pyrrolizidine alkaloids (PAs) were extracted as free tertiary bases and polar N-oxides in a merely one-step liquid-liquid partitioning (LLP) in separation funnel and subsequently pre-fractionated by preparative multiple-development (MD) thin-layer chromatography (TLC) on silica gel plates. In this way three alkaloid fractions of different polarities and retention on silica gel plates were obtained as: the most polar N-oxides of the highest retention, the tertiary bases of medium retention, and diesterified N-oxides of the lowest retention. The former fraction was reduced into free bases by sodium hydrosulfite and purified by LLP on Extrelut-NT3 cartridge. It was further analysed together with the two other fractions by high-performance liquid chromatography (HPLC)-ion-trap mass spectrometry with atmospheric pressure chemical ...
Results of tests on the 1 kg/h continuous reactor for the hydroliquefaction of coal are described. The reactor was operated at 415-435 C and 21 MPa using a continuous stirred reactor with a retention time of about 2 hours. All product oils were recovered by distillation. Sub-bituminous coal was found to give the best product yield. Tests using 5% red mud and 3% improved red mud showed significant increases in oil yield. (4 refs.)
Paraspeckles (PSPs) are nuclear bodies associated with the retention in the nucleus of specific mRNAs. Two isoforms of a long noncoding RNA (NEAT1_v1/Menε and NEAT1_v2/Menβ)...Full Text Available
Load-deflection characteristics of alumina and alumino-silicate fibrous blankets were experimentally determined. Load retention and springback capability of combinations of these materials were measured in a 10,000-hour test at surface temperatures of 650 to 1000"0C (1200 to 1832"0F). Experimental results are presented and future testing plans are discussed.
It has been shown for the first time that astatine is capable of undergoing addition reactions to unsaturated hydrocarbons. A new compound of astatine, viz., ethylene astatohydrin, has been obtained, and its retention numbers of squalane, Apiezon, and tricresyl phosphate have been found. The influence of various factors on the formation of ethylene astatohydrin has been studied. It has been concluded on the basis of the results obtained that the univalent cations of astatine in an acidic medium is protonated hypoastatous acid.
Single doses of lead (trace to 445 mg/kg) were administered per os to suckling and adult mice. Both groups exhibited dose-independent lead retention when doses of 4 to 445 mg/kg were administered. However, developmental differences in the fraction of initial dose (FID) retained were evident for all doses administered. A much larger FID was retained in both age groups following administration of carrier-free "2"0"3Pb. The results are consistent with a mechanism of gastrointestinal lead absorption comprising two or more processes. Developmental differences were also observed in organ lead concentration relative to whole body concentration for kidneys, skull and brain 6 days following lead administration. Lead retentions (relative to whole body retention) in brain and in bone were linearly related to dose of lead administered in both suckling and adult age groups. Though uptake of lead into brain and into femur was observed to ...
Uranyl nitrate ("2"3"3U) was retained mainly in lung, skeleton, pelt and kidney 60 days after inhalation exposure. The concentration in lung exceeded that in other tissues. Preliminary results with "2"3"2U indicate retention in lung similar to that of "2"3"3U, at total deposited mass levels of 0.1 #mu#g or less.
Volume 2 of the water resources data for the 1992 water year for Oklahoma consists of record of stage, discharge, and water quality of streams; stage, contents, and water quality of lakes or reservoirs; and water levels of ground-water well. The report contains discharge records for 136 gaging stations; stage and contents for 31 lakes or reservoirs; water quality for 50 gaging stations. Also included are 61 partial-record or miscellaneous streamflow stations and 28 ground-water sites.
Chemical-looping combustion is an indirect combustion technology with inherent separation of the greenhouse gas CO{sub 2}. The feasibility of using NiO as an oxygen carrier during chemical-looping combustion of coal has been investigated experimentally at 800-960{degree}C in the present work. The experiments were carried out in a fluidized bed, where the steam acted as the gasification-fluidization medium. Coal gasification and the reaction of oxygen carrier with the water gas take place simultaneously in the reactor. The oxygen carrier particles exhibit high reactivity above 900{degree}C, and the dry basis concentration of CO{sub 2} in the exit gas of the reactor is nearly 95%. The flue gas composition as a function of the reactor temperature and cyclic reduction number is discussed. At 800-960{degree}C, the dry basis concentration of CO{sub 2} in the flue gas presents a monotonously increasing trend, whereas the dry basis concentration of CO, H{sub 2}, and CH{sub ...
A liquid chromatography tandem mass spectrometry (LC-MS/MS) method was developed for the simultaneous determination of the 10 major components of Da-Cheng-Qi decoction (rhein, emodin, aloe-emodin, chrysophanol, rheochrysidin, naringin, naringenin, hesperidin, magnolol and honokiol) in dog plasma. Plasma samples were spiked with internal standard (ibuprofen), acidified with HCl and extracted twice by liquid-liquid extraction using ethyl acetate. Separation was performed on a YMC-Pack ODS-A C(18) column (5 microm, 150 mm x 4.6 mm) and a C(18) guard column (5 microm, 4.0 mm x 2.0 mm) with methanol-water (92:8, v/v) at a flow rate of 0.3 mL/min. The LC/MS system was operated under the multiple reaction monitoring mode using electrospray ionization in the negative ion mode. All analytes showed good linearity over a wide concentration range (r>0.99). The linear range of the calibration curves was 5000-19.53 ng/mL for rhein; 400-3.13 ng/mL for ...
A new method for the separation and determination of trace amounts of cadmium and zinc in water as their thenoyltrifluoroacetone (TTA) complexes with dibenzo-18-crown-6 (DB18C6) in o-dichlorobenzene has been established by means of synergistic extraction and back-extraction combined with atomic absorption spectrometry. The effect of various factors (synergism with TTA and DB18C6, shaking time, composition of the extracted species, and mutual separation etc.) on the extraction and back-extraction of cadmium and zinc has been in- vestigated. When the mixtures were extracted for 4 min at pH 4.9, only zinc was extracted quantitatively, whereas cadmium remained in the aqueous phase. After the phases were separated, cadmium was again extracted quantitatively at pH 7.5. Then, the two phases were each shaken with 0.05-0.1 mol/l HCl in order to back-extract cadmium and zinc from the organic phases; the ions were determined individually by atomic absorption spectrometry. In ...
As an unconventional surface alloying process, ion implantation has been utilized to improve the active-passive behavior and the pitting resistance of martensitic M50 engineering alloy. In a field simulation study, Cr-implantation only at 150 kev to a fluence of 2 x 10"1"7 ions/cm"2 prevented pitting. The best pitting resistance of the steel was obtained with multiple implantations of Cr and Mo. The intermixing effect of high fluence P-implantation into 304 stainless produced an amorphous surface alloy. The removal of the grain boundaries and the uniformity of the resulting structure had a great influence on corrosion properties. REED analysis indicated that the anodic passive films formed on P-implanted 304 stainless steel at 250 mV (SCE) in 0.5M H_2SO_4 was amorphous. Phosphorus and boron were implanted into 316 stainless steel to study the passivity of 316 stainless. Electrochemical experiments were carried out to evaluate the effects of phosphorus and boron on general and localized ...
Two-phase flow in horizontal parallel channels has been experimentally investigated under fuel cell related operating conditions. Pronounced hysteresis is observed in the pressure drop versus flow characteristic curve when starting from either flooded or dry conditions. When gas is introduced into channels initially filled with water (flooded initial condition), both gas and liquid tend to flow predominantly in one channel at low gas or liquid flow velocities. As the gas flow velocity increases, even distribution of gas and liquid flow in both channels is observed, accompanied with a sudden decrease in the pressure drop. On the other hand, even gas and liquid flow distribution between both channels is found at comparatively lower gas flow velocities when starting with dry-gas flow conditions with liquid introduced into channels filled with gas (stratified flow regime). The flow regimes of this system are visualized in plots of the pressure drop ...
Alloy 600 is used as a material for steam generator tubing in pressurized water reactors(PWR) due to its high corrosion resistance under PWR environment. In spite of its corrosion resistance, stress corrosion cracking(SCC) has occurred on the primary side as well as the secondary side of the tubing. Oxide on steel surfaces in aqueous solution above 100 .deg. C is composed of duplex film structure. Inner layer of the oxide is dense and less porous, which is formed by growth of oxide layer on metal surface. Outer layer of the oxide is loose adhesive, which is formed by dissolution precipitation mechanism. Growth processes occur at the metal/oxide and oxide/electrolyte interfaces and are controlled by transport of the layer forming species through the layer, i.e. by the inward diffusion of oxygen including electrolyte species and the outward diffusion of metal cations. Understanding of basic electrochemical behaviors about anodic dissolution and passivation of bare ...
Donnan dialysis with ion-exchange membranes was studied under various kinds of experimental conditions using ions of different valences. The diffusion coefficients (D{sub d}) of various kinds of ions in the ion-exchange membrane were obtained by curve fitting an equation derived from the mass balance to three kinds of Donnan dialytic experiments. It was found that the value of D{sub d}/D{sub s} using D{sub d} of monovalent ions in Donnan dialysis with a set of monovalent feed ions and bivalent driving ions was 1/175, where D{sub s} represents a diffusion coefficient in solution. D{sub s} was calculated from the Nernst-Einstein equation substituted by the ionic conductance of ions at infinite dilution in water. Using D{sub d} of bivalent ions in Donnan dialysis with the same set led to a D{sub d}/D{sub s} value of 1/438. Moreover, using D{sub d} in Donnan dialysis with the same set, the value of D{sub d}/D{sub e} was kept constant at 0.4 (D{sub ...
A method and apparatus for nuclear borehole logging, and in particular, neutron porosity logging, uses a neutron source, and a pair of spaced lithium detectors, preferably Li"6I crystal or Li"6 doped glass, to detect neutrons emitted from a borehole formation being logged. The spectrum developed by the lithium detectors is processed to remove the gamma ray background radiation and the hydrogen absorption peak, thus allowing a more accurate neutron count. A Gaussian curve is fitted to the neutron peak of the spectrum, the curve eliminating the hydrogen absorption peak. The area under this Gaussian curve represents the neutron count. (author).
This paper presents a new method for the determination of the energy gap of superconductors. The V/sub max//kT versus ..delta../kT curve was calculated from tunneling theory. The maximum voltage in differential conductance V/sub max/ was measured from the electron tunneling spectrum. From V/sub max//kT and the curve, one can easily calculate the energy gap value ..delta... This method is simple, and the accuracy almost approaches that of the curve-fitting method.
This paper presents a new method for the determination of the energy gap of superconductors. The V/sub max//kT versus #DELTA#/kT curve was calculated from tunneling theory. The maximum voltage in differential conductance V/sub max/ was measured from the electron tunneling spectrum. From V/sub max//kT and the curve, one can easily calculate the energy gap value #DELTA#. This method is simple, and the accuracy almost approaches that of the curve-fitting method.
With a computerized curve fitting method the trapping parameters of TLD-100 chips were calculated after #alpha#-, #beta#- and #gamma#-irradiation. The absorption of radiation produces an additional glow peak at 250 deg C, and the dominant one arises at 280 deg C. After the analysis of the glow curves only a little LET-dependence of the trap depths and that of the half widths was detected. The charge densities after irradiation before heating of the taps responsible for the high temperature glow peaks (T>240 deg C) show a LET-dependence. (author).
Condensing curves are presented for a number of two-component mixed hydrocarbon working fluids which are potentially usable in binary geothermal cycles. Performance of geothermal thermodynamic cycles incorporating these fluids has been evaluated under separate cover; two figures summarizing the results of those evaluations have been included here for continuity. The purpose of this report is: first, to document the condensing curves which were used in the mixed fluid cycle analyses, and second, to provide background useful in the preliminary evaluation of heat rejection systems for advanced geothermal electric power plants utilizing mixed hydrocarbon working fluids. Some concluding remarks are presented.
The automatic interpretation of apparent resistivity curves from horizontally layered earth models is carried out by the curve-fitting method in three steps: (1) the observed VES data are interpolated at equidistant points of electrode separations on the logarithmic scale by using the cubic spline function, (2) the layer parameters which are resistivities and depths are predicted from the sampled apparent resistivity values by SALS system program and (3) the theoretical VES curves from the models are calculated by Ghosh's linear filter method using the Zhody's computer program. Two soundings taken over Takenoyu geothermal area were chosen to test the procedures of the automatic interpretation.
... Chem. Res., in press, 2006. 8. Smith, BL, Bruno, TJ, Advanced distillation curve measurement with a model predictive temperature controller. Int. ...
The inverse problem of interpreting the SS 433 optical light curves is solved for a geometrically thick model accretion disk around the compact relativistic object: most likely a black hole.
F4. Totai Cost by System. Two K-l's will be built to assure successful COTS Demos. ...... has started that learning curve.with the Falcon 1 first stage. ...
This paper proves that it is practicable to build a new power model which can work efficiently at night by using a type of fluorescence material. The utilization efficiency of photovoltaic cell is improved by prolonging the actual working hours of the cell within 24 hours. Both theoretical analysis and experiment on this model are carried out, and base on which the current-time curve (I-t curve) is depicted. It shows that the model which applies the fluorescence material to photovoltaic system is available. According to the analysis and comparison between the attenuating curve of the material and I-t curve of the power system, we can conclude that the weak illumination and the mismatch on wavelength are primary reasons for the low current. Finally, several improved measures of this power model for practical application are given, and it is expected to provide a new thought for photovoltaic study. ...
BackgroundMovement regularities are inherently present in automated goal-directed motions of the primate's arm system. They can provide important signatures of intentional behaviours...Full Text Available
... This paper presents our research in neural learning for predicting ... Denote this feature set as F4. ... can be observed that the SOC curves generated by ...
In an effort to explore Diffraction Enhanced Imaging of bone tissue, experiments were performed to determine if it was possible to use Diffraction Enhanced Imaging to detect microdamage in bovine cortical bone. Measurements were made at the National Synchrotron Light Source where pre- and post-fatigue rocking curve widths of the bone were studied. The rocking curve widths were then compared. Since no consistent pattern of narrowing or broadening of the rocking curve emerged, it is likely that the ultra-small-angle X-ray scattering present in the bone overshadowed any additional changes to rocking curve caused by microdamage of the bone. Larger bone structures were able to be visualized which suggests that microdamage may be visualized with a higher resolution detector.
Using the Galaxy as an example, we study the effect of Formula Not Shown force on the rotational curves of gas and plasma in galaxies. Acceptable model for the galactic magnetic field and plausible physical parameters are used to fit the flat rotational curve for gas and plasma based on the observed baryonic (visible) matter distribution and Formula Not Shown force term in the static MHD equation of motion. We also study the effects of varied strength of the magnetic field, its pitch angle and length scale on the rotational curves. We show that Formula Not Shown force does not play an important role on the plasma dynamics in the intermediate range of distances 6?12?kpc from the centre, whilst the effect is sizable for larger r (r?15?kpc), where it is the most crucial.
The nature of the `inner engine' that accelerate and collimate the relativistic flow at the cores of GRBs is the most interesting current puzzle concerning GRBs. Numerical simulations have shown that the internal shocks' light curve reflects the activity of this inner engine. Using a simple analytic toy model we clarify the relations between the observed $ \\gamma $-rays light curve and the inner engine's activity and the dependence of the light curves on the inner engine's parameters. This simple model also explains the observed similarity between the observed distributions of pulses widths and the intervals between pulses and the correlation between the width of a pulse and the length of the preceding interval. Our analysis suggests that the variability in the wind's Lorentz factors arises due to a modulation of the mass injected into a constant energy flow.
... F4 ... Sublethal Toxicity of Nine Pesticides on Olfactory Learning Performances of ... Daphnia and Preparation of Dosage- Mortality Curves for Pesticides ...
We consider the problem of minimal (multiplicative) complexity of polynomial multiplication and multiplication in finite extensions of fields. For infinite fields minimal complexities are known [Winograd,...Full Text Available
We have recently introduced several important improvements in the measurement of distillation curves for complex fluids. This new method is a significant improvement over current approaches, with features including a composition-explicit data channel for each distillate fraction (for both qualitative and quantitative analysis), trace chemical analysis of each distillate fraction, and a corrosivity assessment of each distillate fraction. In the present contribution, we present the application of the advanced distillation curve method to a bio-derived crude oil prepared from swine manure. One motivation behind the work was to precisely measure the distillation curve of the oil derived from swine manure with our advanced distillation apparatus and compare the bio-derived oil to traditional pe...
In this model, without dark matter, the flat rotation curves of galaxies and the mass-to-light ratios of clusters of galaxies are described quantitatively. The hypothesis is that the agent of gravitational...Full Text Available
Computing the topology of an algebraic plane curve $\\mathcal{C}$ means to compute a combinatorial graph that is isotopic to $\\mathcal{C}$ and thus represents its topology in $\\mathbb{R}^2$. We prove that, for a polynomial of degree $n$ with coefficients bounded by $2^\\rho$, the topology of the induced curve can be computed with $\\tilde{O}(n^8(n+\\rho^2))$ bit operations deterministically, and with $\\tilde{O}(n^8\\rho^2)$ bit operations with a randomized algorithm in expectation. Our analysis improves previous best known complexity bounds by a factor of $n^2$. The improvement is based on new techniques to compute and refine isolating intervals for the real roots of polynomials, and by the consequent amortized analysis of the critical fibers of the algebraic curve.
A large Bragg-curve spectrometer has been constructed and tested. The detector has a cylindrical geometry and operates with a homogeneous electric field. Energy resolutions of <0.8% and Z resolutions of Z/..delta..Z=80 have been achieved for eleastically scattered /sup 58/Ni ions. These results demonstrate the suitability of this large solid-angle detector for use in a wide variety of heavy-ion scattering experiments.
A large Bragg-curve spectrometer has been constructed and tested. The detector has a cylindrical geometry and operates with a homogeneous electric field. Energy resolutions of <0.8% and Z resolutions of Z/#DELTA#Z=80 have been achieved for eleastically scattered "5"8Ni ions. These results demonstrate the suitability of this large solid-angle detector for use in a wide variety of heavy-ion scattering experiments. (orig.).
A new method of particle identification of heavy ions through the measurement of the Bragg curve centroid and particle energy has been developed using a gas ionization chamber with a resistive anode layer. Z-resolutions comparable to the conventional ..delta..E-E counter telescope could be rather easily attained.
A new method of particle identification of heavy ions through the measurement of the Bragg curve centroid and particle energy has been developed using a gas ionization chamber with a resistive anode layer. Z-resolutions comparable to the conventional #DELTA#E-E counter telescope could be rather easily attained. (orig.).
A new article identification method based on the measurement of Bragg-curve centroids using a gas-filled ionization chamber has been improved for detection of low-energy particles around 1 MeV per nucleon by introducing a nonuniform distribution of resistance on the anode electrode. Almost the same quality of Z-resolutions as in the conventional ..delta..E-E method could be obtained up to Z=19.
In the present study the Pb content in Bi(2223) phase by regression or curve fitting method are optimized. The best fitting curve can be obtained by the method of least square. To study the effect of Pb content in Pb substituted Bi (2223) superconductors, prepared by solid state reaction method data is obtained. The deviation of T_c from the target value for different Pb content is summarized
Projectilelike fragments following the 80 MeV /sup 16/O+/sup 27/Al reaction have been detected using a Bragg-curve spectroscopy ionization chamber (BCS-IC). The atomic number is deduced from the Bragg-peak amplitude. Nitrogen isotopes are clearly resolved using either range or energy loss data. This is the first application of the BCS method for complete ion identification in a heavy-ion-induced reaction.
Projectilelike fragments following the 80 MeV "1"6O+"2"7Al reaction have been detected using a Bragg-curve spectroscopy ionization chamber (BCS-IC). The atomic number is deduced from the Bragg-peak amplitude. Nitrogen isotopes are clearly resolved using either range or energy loss data. This is the first application of the BCS method for complete ion identification in a heavy-ion-induced reaction.
The macroscopic behavior of magnetostrictive materials results from domain evolutions occurring at a microscopic scale. The author shows how to compute magnetization and magnetostriction curves by appraising the behavior of the underlying microstructures. The method hinges on an averaging device (Young measures), which allows one to pass from the microscopic to the macroscopic scale. He takes into account the kinematical constraints on the accommodation of elastic effects, and he highlights the role of material symmetry in the selection of energetically optimal microstructures.
This article analyses the role of energy intensity and the relationship between CO{sub 2} emissions and primary energy in order to explain the evolution of CO{sub 2} emissions by unit of real GDP. It also distinguishes two different meanings of CO{sub 2} emissions Kuznets curve hypothesis: the weak and the strong sense. It considers the case of Spain in the period 1972-1997 as an example in which there is not any evidence supporting this hypothesis in either sense. (author)
The RKR potential energy curves are constructed for the ground states of diatomic hafnium oxide and thorium oxide. Using Lippincott and Hulburt-Hirschfelder potential function the dissociation energies are estimated by curve fitting method. The H-H potential function was found to give a better fit in both cases. The dissociation energies of hafnium oxide and thorium oxide are estimated as 9.04 #+-# 0.02 eV and 10.34 #+-# 0.01 eV respectively. (author).
Ionization counters employing Bragg curve spectroscopy have been constructed for use in a 4? geometry. These detectors compare very favorably in terms of both energy and charge resolution with small solid angle devices. These detectors have a large dynamic range because they are backed by scintillation detectors, and are thus capable of detecting and identifying particles with energies from 1 MeV/nucleon up to 200 MeV/nucleon.
Ionization counters employing Bragg curve spectroscopy have been constructed for use in a 4{pi} geometry. These detectors compare very favorably in terms of both energy and charge resolution with small solid angle devices. These detectors have a large dynamic range because they are backed by scintillation detectors, and are thus capable of detecting and identifying particles with energies from 1 MeV/nucleon up to 200 MeV/nucleon. (orig.).
Ionization counters employing Bragg curve spectroscopy have been constructed for use in a 4#pi# geometry. These detectors compare very favorably in terms of both energy and charge resolution with small solid angle devices. These detectors have a large dynamic range because they are backed by scintillation detectors, and are thus capable of detecting and identifying particles with energies from 1 MeV/nucleon up to 200 MeV/nucleon. (orig.).
The operation principle, construction and characteristics of the Bragg curve spectroscopy detector (BCS detector) are described. The electric field of the BCS detector is parallel to the particle trajectories. The detector was tested by 8.78 MeV and 6.02 MeV #alpha# particles from a ThC-ThC's source. The energy resolutions are 1.5% and 2.6% respectively for two groups of #alpha# particles, and the charge resolution is 2.7%. Further test experiments with heavy ions will be arranged.
A novel approach is presented to extract relevant parameters associated with the energy loss of ejectiles from nuclear reactions obtained by digitizing the signals of a Bragg curve spectrometer. New and more powerful computational paradigms allow a more thorough pulse-shape analysis. This is fulfilled using a back-propagation artificial neural network as a pattern identifier. The known problem of over-training is discussed.
A computerised curve-fitting method was developed to calculate the trapping parameters in LiF TLD-100 and LiF:Mg, Ti. After irradiation in a "6"0Co field and with X rays emitted at different voltages the TL process is best described by first-order kinetics. A dependence of the trapping parameters on both the concentration of Mg and Ti and photon energy was detected. (author).
A large-acceptance Bragg curve spectrometer with a longitudinal electron collection field and a segmented anode has been constructed and tested. The effects on the charge resolution of the entrance angle and entrance position of the incident particle have been studied. Simulations have been done in order to isolate the contribution to the overall detector performance of the signal-shaping electronics from that of the intrinsic design of the detector. ((orig.))
Water-resources data for the 1993 water year for Minnesota consists of records of stage, discharge and water quality of streams; stage, contents, and water quality of lakes and reservoirs; and water levels and water quality in wells and springs. This volume contains discharge records for 58 gaging stations; stage and contents for 9 lakes and reservoirs; water quality 15 stream stations, 1 lakes station, 1 precipitation station, and water levels for 15 observation wells. Also included are 61 high-flow partial-record stations. Additional water data were collected at various sites, not part of the systematic data collection program and are pulished as miscellaneous measurements.
Water-resources data for the 1991 water year for Minnesota consist of records of stage, discharge and water quality of streams; stage, contents, and water quality of lakes and reservoirs; and water levels and water quality in wells and springs. The volume contains discharge records for 60 gaging stations; stage and contents for 9 lakes and reservoirs; water quality for 18 stream stations, 1 lake station, 22 partial-record sites, 1 precipitation station, 108 wells; and water levels for 119 observation wells. Also included are 59 high-flow partial-record stations. Additional water data were collected at various sites, not part of the systematic data collection program and are published as miscellaneous measurements or low-flow investigations.
In the National Water Plan it is described which measures must be taken to keep the Netherlands safe and livable for future generations and to make use of the chances offered by water.
swimmers in or around the water. Designate a responsible adult who can swim and knows CPR to watch swimmers in or around water. The supervisor should not be involved in any...
The thermodynamic characteristics of sorption of the isomeric tricyclo[5.2.1.02.6]decane (tetrahydrodicyclopentadiene, TDCPD) molecules were for the first time determined experimentally and by molecular statistical methods under the conditions of gas-adsorption chromatography on graphitized thermal carbon black and gas-liquid chromatography on stationary liquid phases of different polarities (Apiezon L and Carbowax 20M). The effects of the chemical nature of sorbents on the retention of the TDCPD isomers are considered. A procedure for calculating the thermodynamic characteristics of adsorption of molecules with a complex structure is suggested within the framework of the atom-atom approximation of the semiempirical molecular statistical theory of adsorption for the example of isostructural norbornane molecules. The procedure involves simultaneous variation of geometric parameters and refinement of the parameters that determine the special features of the ...
In developing new brain imaging agents for single photon emission computed tomography (SPECT), we synthesized eleven radioiodinated phenoxyacetic acid derivatives and investigated the relationship between the chemical structure and in vivo characteristics. Biodistribution studies in mice revealed high initial brain uptake for all the compounds. Blood radioactivity level depended markedly upon the chemical stability of the compound. The #alpha#,#alpha#-dimethylester derivative (1e), amide derivatives (2a-c) and diamine derivatives (3a, b, 4), which were stable to hydrolysis, showed low blood activity levels following i.v. administration. Disappearance of the ester and amide compounds from the brain was rapid. However, the diamine derivatives displayed improved retention in the brain. Compounds 3a and 4 possessed the best combination of high brain uptake and sufficient retention to be useful as potential brain imaging radiopharmaceuticals with ...
In response to the consultation from the National Council on Radiation Protection and Measurements (NCRP) to the International Commission on Radiological Protection (ICRP) committee 2, retention and excretion of 239Pu deposited at wound site were calculated by coupling together the proposed NCRP wound model and the current ICRP systemic model of Pu. The physicochemical forms considered were the soluble form categorized into 'Strong Retention', and the colloidal, particulate and fragmentary forms. The results are summarized as follows. If in soluble form, immediate medical intervention is needed to prevent uptake of radionuclides to body tissues, and prompt wound monitoring is essential for an accurate estimation of the initially deposited radioactivity. If in particulate form, a multi-component exponential equation leads to an overestimation of the absorption rate to blood because of significant lymph node drainage. The committed doses in the ...
The efficacy of external flooding of a reactor vessel as a severe accident management strategy is assessed for an AP600-like reactor design. The overall approach is based on the Risk Oriented Accident Analysis Methodology (ROAAM), and the assessment includes consideration of bounding scenarios and sensitivity studies, as well as arbitrary parametric evaluations that allow the delineation of the failure boundaries. Quantification of the input parameters is carried out for an AP600-like design, and the results of the assessment demonstrate that lower head failure is physically unreasonable. Use of this conclusion for any specific application is subject to verifying the required reliability of the depressurization and cavity-flooding systems, and to showing the appropriateness (in relation to the database presented here, or by further testing as necessary) of the thermal insulation design and of the external surface properties of the lower head, including any applicable coatings. The ...
In accordance with Department of Energy (DOE) Regulations surveys for wetland presence or absence were conducted in September 1996 on the DWI-1630 site (Witherspoon Landfill) located in South Knoxville, Knox County, Tennessee. The DWI-1630 site includes a closed, capped landfill area, areas of past disturbance adjacent to the capped area, and patches of hardwood forest. Wetlands were identified on the landfill cap and in a small bottomland that was formerly used for a retention pond in the southwest corner of the DWI-1630 site. The wetlands identified on the cap are man-induced, atypical situation wetlands. These areas have hydrophytic vegetation and wetland hydrology, but the soils do not have hydric characteristics. Wetland development appears to be due to a combination of the grading or subsidence of the clay landfill cap, the low permeability of the clay fill soil, and the absence of surface drainage outlets from the depressions. These atypical situation ...
Previous work suggests that supplemental ascorbic acid (AA) may inhibit intestinal copper absorption by stabilizing the less absorbable cuprous state. The authors studied copper absorption in healthy men (age 19-32) fed a constant diet with different amounts of ascorbic acid supplements. The 6 men were confined to a metabolic unit for the entire 14 week study. The basal diet consisted of a 7 day rotating menu which provided an average of 2.1 mg Cu/d and was adequate in all other nutrients except AA (5 mg/d). The basal diet was supplemented with either zero, 60, or 600 mg of AA daily, added to grape juice and consumed at each meal. All feces were collected. Blood was taken weekly for monitoring AA and copper status. Copper absorption was determined by both balance and "6"5Cu stable isotope techniques. As determined by fecal Cu excretion, varying intakes of AA between 0.1 to 10 times the RDA had no significant effect on copper retention. This is consistent with the ...
The objective of the study was to investigate neuronal processing during the encoding, retention and retrieval phases of a serial visual working memory task. Particularly, we were interested in how these phases are affected by working memory load and how processing is modulated by methylphenidate. Healthy adults were asked to memorize the order of four, five or six pictures under methylphenidate (20mg) and under placebo while brain electrical activity was recorded. On the performance level, the number of correct responses decreased with increasing working memory load. Concerning brain electrical activity, in the encoding phase P3 amplitudes increased at midline electrodes with increasing memory load while load had no effect in the retention and retrieval phase. Medication neither influenced performance nor the different processing stages significantly. Our data provide evidence that during the encoding phase more attentional resources are ...
A novel bioelectrochemical membrane reactor (BEMR), which takes advantage of a membrane bioreactor (MBR) and microbial fuel cells (MFC), is developed for wastewater treatment and energy recovery. In this system, stainless steel mesh with biofilm formed on it serves as both the cathode and the filtration material. Oxygen reduction reactions are effectively catalyzed by the microorganisms attached on the mesh. The effluent turbidity from the BEMR system was low during most of the operation period, and the chemical oxygen demand and NH(4)(+)-N removal efficiencies averaged 92.4% and 95.6%, respectively. With an increase in hydraulic retention time and a decrease in loading rate, the system performance was enhanced. In this BEMR process, a maximum power density of 4.35 W/m(3) and a current density of 18.32 A/m(3) were obtained at a hydraulic retention time of 150 min and external resister of 100 ?. The Coulombic efficiency was 8.2%. Though the ...
Chiral auxiliaries are promising emerging tools for the asymmetric synthesis of octahedral metal complexes. We recently introduced chiral salicyloxazolines as coordinating bidentate chiral ligands which provide excellent control over the metal-centered configuration in the course of ligand substitution reactions and can be removed afterward in an acid-induced fashion under complete retention of configuration (J. Am. Chem. Soc. 2009, 131, 9602-9603). Here reported is our detailed investigation of this sequence of reactions, affording virtually enantiopure ruthenium polypyridyl complexes. The control of the metal-centered chirality by the coordinated chiral salicyloxazolinate ligand was evaluated as a function of reaction conditions, the employed bidentate 2,2'-bipyridine and 1,10-phenanthroline ligands, and the substituent at the asymmetric 5-position of the oxazoline heterocycle. Most striking was the strong influence of the reaction solvent, with aprotic solvents ...
Six kinds of diamino-dithiol compounds are labelled with "9"9Tc"m by ligands exchange reaction. Their ligands exchange percentage is over 95%. The biodistribution of one of these compounds in mice shows 0.88% brain uptake after two minutes and 0.28% after 15 minutes respectively. Although the brain uptake is lower for this compound, it has longer retention in brain. So, the experiment results are valuable to the design of new brain imaging agent in the future.
In acute intoxication, uranium (U) not only inhibits bone formation but its excretion in urine also causes renal damage. The former effect is ameliorated by tetracycline (TC), probably due to its chelation property, which might also prevent U deposition in bone. Chemical determination of U incorporated in bone and a histological study of the kidneys were performed on animals injected with U and then treated with TC. The results showed that TC was unable to prevent the binding of U to bone while it exacerbated U-induced renal damage.
Radioiodinated ..cap alpha..-bungarotoxin, the venom of Bungarus multicinctus, is commonly used for the detection and quantification of nicotinic acetylcholine receptors (nAChR) and anti-nAChR antibodies. A radioiodination method is described which is simple and yields a fully active product which, after fractionation, has a specific activity tenfold higher (900 Ci/mmol) than those routinely used, resulting in enhanced sensitivity of assays and conservation of material, especially muscle extracts.
Iron alloys and aluminum were nitrogen implanted in a controlled oxygen atmosphere and the role of hydrogen on the surface etching mechanisms studied. The surface composition was analyzed by in situ photoemission electron spectroscopy (XPS). In iron alloys, hydrogen strongly etches oxygen, improving nitrogen retention on the surface. On the other hand, hydrogen removes nitrogen from aluminum surfaces, with a deleterious effect on the nitriding effectiveness. The oxygen removal in iron alloys is associated with the catalytic effect of electrons in d-orbitals and the nitrogen removal in aluminum is associated with a steric effect.
When combining aerosol retention components in the dissolver offgas stream of a reprocessing plant, the behavior both of the individual aerosol filter stages and the overall removal efficiency of all filters connected in series vis-a-vis an aerosol spectrum to be expected must be determined for the benefit of the licensing authority. A fast method of determining removal efficiencies is described, which can also be applied in hot operation. This method was used to demonstrate, with high certainty, decontamination factors of a whole filter train in the range of 10"7.
Forty-three patients with basal and squamous cell carcinomata arising on the pinna were treated radically using a 10 MeV electron beam. The technique and dosage are described and discussed. Primary cancer control with retention of the pinna was achieved in 34 patients. Salvage pinnectomy was performed in four patients for recurrence and one patient for radiation necrosis. Two patients with large primary tumours failed to resolve and died of their disease. The advantages for the patient of the policy of primary radical electron beam therapy are discussed.
Dietary supplements of about 5 g/kg of a number of amino acids increased tissue lead concentrations in newly weaned rats but decreased them in older rats. The retention of both oral and intraperitoneal lead was affected. The uptake of "2"0"3Pb by tissues was reduced when methionine was given in the diet over a period of 5 weeks or when it or ethionine was given by mouth 24 h before the activity was measured. In the liver the fraction of the total activity found in the nuclei and mitochondria was increased by methionine, but in the kidney only the fraction found in nuclei was increased.
The goals of this paper are to describe the fabrication and complete evaluation of a dihydropyridine <- -> pyridinium salt type redox system for the delivery of radioiodinated agents to the brain. Tissue distribution studies of "1"2"5I-labeled 4-iodoaniline and the redox agents were performed in rats. ["1"2"5I]Iodoaniline initially showed moderate brain uptake with subsequent release of the radioactivity from the brain. ["1"2"5I]Iodoaniline, however, when coupled to a dihydropyridine carrier showed significantly higher uptake and retention in the brain. (author).
The adsorption properties of four samples of ..cap alpha..-BN were studied by means of gas chromatography. The particles of ..cap alpha..-BN particles, according to data obtained by electron microscopy, have the shape of thin platelets. A sample of ..cap alpha..-BN prepared from magnesium polyboride was found to be the most nearly homogeneous adsorbent. For a number of n-alkanes, benzene, and alkylbenzenes, data have been obtained on the retention volumes (Henry constants) and the differential heats of adsorption for surface coverages approaching zero. These thermodynamic data on the adsorption showed that ..cap alpha..-BN, like graphitized thermal carbon black, is a nonspecific adsorbent.
This facility has treatment capacity of 12 kg/hr, and is equipped with a furnace, two ceramic filter chambers, each of which hangs inside the 36 ceramic filter elements having mean pore size of 44 #mu#m. Three series of experiments were performed during a period from October 1972 to August 1973. The first was measurement of the change of pressure drop of the primary and the secondary filters after an operation of 52 days (352 hours). The pressure drop of the primary filter did not change during the operation, but the secondary brought a fairly large increment, from 79 to 140 mmAq. The second was measurement of the after-burning effect of the primary filter for the soot and tar in the off-gas. Through the after-burning most of the soot was removed from the off-gas, though the tar was not perfectly taken off. At the secondary filter, some of the tar was burnt, but most of it was caught by the filter as aerosol. The third was measurement of decontamination factors of radioactivities of ...
Southeastern Finland belongs to the area covered by the Weichselian ice sheet, where the release of the ice load caused a rapid isostatic rebound during the postglacial time. While the mean overall apparent uplift is of the order of 2 mm/yr today, in the early Holocene time it was several times higher. A marked decrease in the rebound rate occurred around 8500 BP, however, since then the uplift rate has remained high until today, with a slightly decreasing trend towards the present time. According to current understanding there have neither been temporary increases nor decreases in the rate of uplift during the postglacial time. Even so, it is not known for sure whether there are regional irregularities on the rebound in Finland. Concurrently with land uplift, relative sea-level changes in the Baltic basin were also strongly affected by the global eustatic rise of sea-level. During the early Litorina Sea stage on the southern coast of Finland around 7000 BP, the rise in sea-level ...
Complete text of publication follows. Baikal is an ancient unique lake. The sweet water of Baikal is crystal clean; it concentrates oxygen and contains scarce silicon. This feature is provoked very particular interest for scientists and poses some awkward questions concerning the preservation of Baikal's ecosystem. A profound investigation of fish otholiths, animal teeth, sponges, valves of mollusks and diatom algae provides chronological information, possibility to reconstruct the events proceeding in the environment based on variations of their chemical composition. Because these study objects are small-sized, and some of them are micron-size, application of the electron-probe microanalysis turns to be quite productive. The goal of this study is to disclose performance capabilities of this method while investigating the Baikal flora and fauna. Investigations were performed by devices JCXA-733 and JXA-8200 using the electron microscope and x-ray microprobe modes. ...
This study aims to investigate the difference in the interaction of antimicrobial peptides with two classes of zwitterionic peptides, phosphatidylethanolamines (PE) and phosphatidylcholines (PC). Further experiments were performed on model membranes prepared from specific bacterial lipids, lipopolysaccharides (LPS) isolated from Salmonella minnesota. The structure of the lipid-peptide aqueous dispersions was studied by small-and wide-angle X-ray diffraction during heating and cooling from 5 to 85 C. The lipids and peptides were mixed at lipid-to-peptide ratios 10-10000 (POPE and POPC) or 2-50 (LPS). All experiments were performed at synchrotron soft condensed matter beamline A2 in Hasylab at Desy in Hamburg, Germany. The phases were identified and the lattice parameters were calculated. Alamethicin and melittin interact in similar ways with the lipids. Pure POPC forms only lamellar phases. POPE forms lamellar phases at low temperatures that upon heating transform into a highly ...
An improved process is disclosed for reducing the water content of coal containing bound water by releasing at least a portion of the bound water by maintaining the coal at a temperature from about 220/sup 0/ to about 500/sup 0/ F. in the presence of water at a pressure sufficient to maintain at least portion of the water in a liquid phase for a time sufficient to release at least a portion of the bound water wherein the improvement comprises contacting the coal during such treatment with an active material selected from the group consisting of carboxylic organic acids containing up to about 6 carbon atoms, phenol, phenolic acids and inorganic acids.
In the United States, economic growth increasingly requires that greater volumes of freshwater be made available for new users, yet supplies of freshwater are already allocated to existing users. Currently, water for new users is made available through re-allocation of xisting water supplies-for example, by cities purchasing agricultural water rights. Water may also be made available through conservation efforts and, in some locales, through the development of ''new'' water from non-traditional sources such as the oceans, deep aquifer rackish groundwater, and water reuse.
Jet Propulsion Laboratory. California Institute of Technology. Pasadena, California. Energy and Water Conservation. Steve Rigdon. Facilities Energy Manager ...
This thesis deals with the analysis of dominant loss mechanisms in direct methanol fuel cells (DMFC) and hydrogen fed polymer electrolyte membrane fuel cells (PEFC) by means of experimental characterization and modeling work. Due to different fuels used in these two fuel cell types, the dominant loss mechanisms are different in their nature. All in-situ characterization techniques that are used in this work are based on a novel test fuel cell with embedded reference electrodes. The first part of this work presents a new concept for realizing a reference electrode configuration in a polymer electrolyte membrane fuel cell by means of laser ablation. The laser beam is used to evaporate a small gap into the electrode surface of a catalyst coated membrane (CCM) to isolate the reference electrode from the working/counter electrode (WE/CE). This method enables the simultaneous ablation of the electrodes on both sides of the CCM because the membrane is transparent for the laser beam. ...
The space environment consists of a varying field of radiation particles including high-energy ions, with spacecraft shielding material providing the only major protection to astronauts from harmful exposure. Unlike low-linear energy transfer (LET) {gamma} or X-rays, the presence of shielding does not always reduce the radiation risks for energetic charged particle exposure, since the dose delivered by the charged particle increases sharply as the particle approaches the end of its range, a position known as the Bragg peak. The Bragg curve does not necessarily represent the biological damage along the particle traversal, and the 'biological Bragg curve' is dependent on the energy and the type of the primary particle, and may vary for different biological endpoints. Here we used a unique irradiation geometry to measure the biological response across the Bragg curve in human fibroblasts exposed to ...
The water and steam circuits of steam generators in pressurized-water nuclear power plants are described together with the mechanism of denting, and the corrosion of spacer plates that leads to cracks in tubes by constriction. The different chemical specifications applicable to the water of the secondary circuit of the generators in normal operation and on first commissioning are listed. The results obtained and the measurements of chemical values taken in operation on the water in the secondary circuits of steam generators at Fessenheim and Bugey are presented.
The water and steam circuits of steam generators in pressurized-water nuclear power plants are described together with the mechanism of denting, and the corrosion of spacer plates that leads to cracks in tubes by constriction. The different chemical specifications applicable to the water of the secondary circuit of the generators in normal operation and on first commissioning are listed. The results obtained and the measurements of chemical values taken in operation on the water in the secondary circuits of steam generators at Fessenheim and Bugey are presented.
The growth power-time curves of a strain of petroleum bacteria, B-2, in various kinds of cultures containing different kinds of carbon sources, glucose, n-tetradecane, n-hexadecane and n-octadecane, and different kinds of microemulsions have been determined by using a 2277 Thermal Activity Monitor. The curves showed a single peak for cultures containing a single carbon source, glucose, and two peaks for cultures containing two kinds of carbon sources, glucose and one of the n-alkanes. The first peak indicated that bacteria grew by consuming glucose and the second peak indicated that bacteria grew by consuming n-alkane. The curves were complex when the bacterium grows in a microemulsion culture. According to a kinetic equation of bacterial growth under limited conditions, the rate constants of bacterial growth were obtained. The results showed that the microemulsion culture was more appropriate to bacteria to grow on ...
The Bragg-curve detector of the parallel plate ionization chamber type generates a signal that is a distorted replica of the original Bragg-curve. In result of this distortion, the signal peak height is not only a function of the atomic number of the heavy ion, as it is often stated, but also of the particle mass. This mass effect was studied with the aid of computer simulation, and it was found to be dependent on the Frisch grid to anode gap width and on the detector gas. The charge resolution of the detector is affected very significantly by this mass dependence of the signal peak height. Therefore, a careful selection of the detector gas and the grid to anode gap width is necessary, if good charge resolution over a wide range of heavy ions is required. (orig.).
The difficulty and unstability of the parameter estimation of mass action model for radioimmunoassay are the major obstacles to its application in routine work. A unique robust curve fitting method for the mass action model was introduced. large numbers of simulated data were generated with Monte Carlo method to compare the accuracy and robustness of the robust fitting and the least squre fitting (Marquardt method) of the mass action model. The results demonstrated that the new robusst method significantly increased the accuracy and reliability of data processing with the mass action model. It also markedly reduced the influence of outliers in the fitting of RIA data, and it was always 'convergent'. This robust method could also be applied to other mathematical models which can be transformed into high degree equations and no initial estimates are needed for curve fitting.
It is a traditional method to diagnose electron-cyclotron-resonance (ECR) plasma source, using a single probe to measure the current-voltage curve of the plasma, based on which and theoretic formula the plasma density can be computed. The article adopts a Langmuir probe having a role of emission electrons to measure two different current-voltage curves with and without emission. It is ease to get the plasma potential via the inflexion of the two curves and compute directly various physical quantities by the assistant computer, such as electron temperature, electron/ion density, plasma potential etc. The deviation is about percent 1.8 between the measurement results by traditional and the new method, but the latter has higher efficiency. (authors)
A time-of-flight (TOF) spectrometer has been constructed at the JAERI 20 MV tandem accelerator facility. A position-sensitive start detector, which consists of a thin carbon foil, microchannel plates and a resistive plate, was developed for the TOF measurements through the spectrometer. The time and position resolutions obtained were 120 ps and 0.3 mm for ..cap alpha.. particles from /sup 241/Am, respectively. A two-dimensional position-sensitive detector was also developed to measure the solid angle of the spectrometer and the maximum solid angle obtained was 9.5 msr. As a particle detector a Bragg curve ionization chamber was developed. From the Bragg curves of heavy ions in the detector, energies, ranges and Bragg curve peaks were measured and used for particle identification. The resolving power Z/..delta..Z of the atomic number was about 50.
Enhanced heat transfer in curved rectangular channels depends on at least two geometric factors, the radius of curvature of the duct and the aspect ratio, which is the width/depth ratio of the duct. In this work, an expression for optimum aspect ratio is derived mathematically from a correlation that includes both aspect ratio and bend curvature parameters. Enhancement factors are developed that show optimal, near-optimal, and nonoptimal aspect ratios for curved rectangular ducts. Predicted enhancements are within 25% of published literature results for individual designs, two of which show heat transfer enhancement of 200% over that of a straight duct with turbulent flow. The theoretical maximum enhancement is shown to be about 480% over a straight-duct, turbulent-flow situation. This is not achievable in practice, but near-optimal solutions are achievable, yielding enhancements on the order of 200--300%.
The Bragg-curve detector of the parallel plate ionization chamber type generates a signal that is a distorted replica of the original Bragg-curve. In result of this distortion, the signal peak height is not only a function of the atomic number of the heavy ion, as it is often stated, but also of the particle mass. This mass effect was studied with the aid of computer simulation, and it was found to be dependent on the Frisch grid to anode gap width and on the detector gas. The charge resolution of the detector is affected very significantly by this mass dependence of the signal peak height. Therefore, a careful selection of the detector gas and the grid to anode gap width is necessary, if good charge resolution over a wide range of heavy ions is required.
A noninvasive method is described for estimating local cerebral blood flow (LCBF) and local partition coefficients by means of computed tomographic scanning during inhalation of 30% stable xenon gas in oxygen. Time-dependent xenon concentrations in arterial blood and brain tissue during the wash-in and washout phases are used to calculate partition coefficients and LCBF values by means of a least-squares curve-fitting analysis. Control values for partition coefficient and LCBF obtained from control subjects with minor head trauma in the chronic stage were compatible with those in several past reports, and reproducibility was satisfactory. The theoretic grounds underlying this new method of curve-fitting analysis are discussed.
A noninvasive method is described for estimating local cerebral blood flow (LCBF) and local partition coefficients by means of computed tomographic scanning during inhalation of 30% stable xenon gas in oxygen. Time-dependent xenon concentrations in arterial blood and brain tissue during the wash-in and washout phases are used to calculate partition coefficients and LCBF values by means of a least-squares curve-fitting analysis. Control values for partition coefficient and LCBF obtained from control subjects with minor head trauma in the chronic stage were compatible with those in several past reports, and reproducibility was satisfactory. The theoretic grounds underlying this new method of curve-fitting analysis are discussed.
Internal friction of amorphous Pd/sub 80/Si/sub 20/ metal doped with hydrogen or deuterium was measured with a specially designed apparatus using amorphous metal sheet as a part of the electric oscillating circuit. Two peaks in Q/sup -1/ curve are observed. Applying the peak shift method to the first Snoek-like peak, we can determine the relaxation time from which the microdiffusion coefficient can be calculated. The obtained microdiffusion coefficient is about 10/sup -14/ m/sup 2//s at 200 K, being comparable with the macrodiffusion coefficient obtained from the releasing method. It can, however, not elucidate the hydrogen isotopic effect on the peak temperature of Q/sup -1/ curve, the activation energy for relaxation and the relaxation time from the present work because of the broadness of obtained Q/sup -1/ curve.
A focused ion beam (FIB) is used to accurately sculpt predetermined micron-scale, curved shapes in a number of solids. Using a digitally scanned ion beam system, various features are sputtered including hemispheres and sine waves having dimensions from 1-50 {micro}m. Ion sculpting is accomplished by changing pixel dwell time within individual boustrophedonic scans. The pixel dwell times used to sculpt a given shape are determined prior to milling and account for the material-specific, angle-dependent sputter yield, Y({theta}), as well as the amount of beam overlap in adjacent pixels. A number of target materials, including C, Au and Si, are accurately sculpted using this method. For several target materials, the curved feature shape closely matches the intended shape with milled feature depths within 5% of intended values.
According to the environmental Kuznets curve hypothesis, the relationship between per-capita GDP and per-capita pollutant emissions has an inverted-U shape. This implies that, past a certain point, economic growth may actually be profitable for environmental quality. Most studies on this subject are based on estimating fully parametric quadratic or cubic regression models. While this is not technically wrong, such an approach somewhat lacks flexibility since it may fail to detect the true shape of the relationship if it happens not to be of the specified form. We use semiparametric and flexible nonlinear parametric modeling methods in an attempt to provide more robust inferences. We find little evidence in favour of the environmental Kuznets curve hypothesis. Our main results could be inte...
Many methods have been proposed for the determination of the corrosion current density from polarization curves; the two most commonly used ones are the three-point method and the curve-fitting method. The basis of these methods is a polarization equation that was derived for the complete absence of mass-transport effect or considers the cathodic partial reaction to be under complete mass-transport control. The mixed-control case has been much less investigated, even though this case may quite frequently reflect practical situations. A completely generalized polarization equation is proposed that can be used as a basis for curve-fitting data evaluation under any conditions. This equation was used to determine the error caused by the neglect of mass-transport effect in conventional data evaluation.
From the beginning of the 90s the analysis of the relationships between economic growth and environmental pressures has been influenced by the Environmental Kuznets Curve hypothesis or inverted-U shaped relationship between environmental pressure and per capita income. Following this hypothesis, once achieved certain income level, more economic growth is followed by environmental quality improvement. In this paper, we analyse and discuss the theories that support this hypothesis as well as the empirical evidence on this subject. Further on we analyse the relationship between per capita income and the main environmental pollutants for the case does not support the hypothesis. The empirical evidence shows that economic growth, by itself, does not entail a pollution reduction. (Author) 35 refs.
We have recently introduced several important improvements in the measurement of distillation curves for complex fluids. The modifications include a composition-explicit data channel for each distillate fraction (for both qualitative and quantitative analysis) and corrosivity assessment of each distillate fraction. The composition-explicit information is achieved with a new sampling approach that allows precise qualitative as well as quantitative analyses of each fraction, on the fly. We have applied the new method to a variety of fluids, including simple n-alkanes, rocket propellant, gasoline, jet fuels, and a hydrocarbon fluid made corrosive with dissolved hydrogen sulfide. In the current contribution, we present the application of the advanced distillation curve method to two samples of...
A large acceptance, high stopping power, Bragg curve spectrometer has been developed for use in coincidence experiments with heavy ions. The electron collection fields are radial and position information is obtained from a resistive anode. The detector is 60 cm deep and operates at pressures of up to 2.5 atm of P-10 gas. It is mated to a scattering chamber which allows it to be moved out of plane during coincidence measurements. The detector design was aided by the results of computer simulations of the electron collection process in the detector, and of the signal processing in the electronics. The signals from the Bragg curve spectrometer are recorded in a waveform digitizer and the Bragg peak height, range, position and pileup rejection information are determined from software analysis of the recorded signals. Factors limiting the performance of the detector are discussed, and results obtained with the detector are presented. (orig.).
A large acceptance, high stopping power, Bragg curve spectrometer has been developed for use in coincidence experiments with heavy ions. The electron collection fields are radial and position information is obtained from a resistive anode. The detector is 60 cm deep and operates at pressures of up to 2.5 atm of P-10 gas. It is mated to a scattering chamber which allows it to be moved out of plane during coincidence measurements. The detector design was aided by the results of computer simulations of the electron collection process in the detector, and of the signal processing in the electronics. The signals from the Bragg curve spectrometer are recorded in a waveform digitizer and the Bragg peak height, range, position and pileup rejection information are determined from software analysis of the recorded signals. Factors limiting the performance of the detector are discussed, and results obtained with the detector are presented. (orig.).
Cooling water is sprayed on the outer surface of an upper portion of a container, and a pool is formed by the cooling water flowing down while cooling the container. Further, the cooling water stored in the cooling water pool is recycled by a pump for spraying the cooling water on the outer surface of the upper portion of the container. Sufficient amount of cooling water is supplied for spraying the cooling water to the outer surface of the upper portion of the container so that the outer surface of the container is free from drying and a liquid membrane is formed on the entire surface. The amount of the cooling water is made greater than that of the cooling water evaporated when the entire amount of the heat generate in the reactor core of the reactor is transferred to the cooling ...
Water-resources data for the 1993 water year for Texas are presented in four volumes, and consist of records of stage, discharge, and water quality of streams and canals; and stage, contents, and water quality of lakes and reservoirs; and water levels and water quality of ground-water wells. Volume 3 contains records for water discharge at 134 gaging stations; stage only at 1 gaging stations; stage and contents at 13 lakes and reservoirs; water quality at 81 gaging stations; and data for 30 partial-record and 4 flood-hydrograph partial-record stations. Also included are lists of discontinued surface-water discharge or stage-only stations and discontinued surface-water-quality stations; crest-stage and flood-hydrograph partial-record stations, reconnaissance ...
I present results for the mass spectrum of excited baryons and pentaquarks using overlap fermions and Bayesian curve-fitting method; and magnetic moments and polarizabilities for a variety of hadrons in the background field method.
I present results for the mass spectrum of excited baryons and pentaquarks using overlap fermions and Bayesian curve-fitting method; and magnetic moments and polarizabilities for a variety of hadrons in the background field method.
of first unit and learning curve (LC) factor for hardware, ETR, and WTR recurring cost respectively. ...... 105 FORMAT (12,A6,F4.2,6X.F7 0,F6 OF7 0.12. 2012) ...
The current status of cosmological observations is presented; and the light curves and radiation spectra from supernova SN1987A are used in comparison between expected and observed universal nucleosynthesis and star evolution data./aip/.
This report discusses the following topics: Fusion-fission in light nuclear systems; High-resolution Q-value measurement for the {sup 24}Mg+{sup 24}Mg reaction; Heavy-ion reactions and limits to fusion; and Hybrid MWPC-Bragg curve detector development.
An indicator of when the learning curve reaches a standard is when fuel consumption remains relatively ...... f4 7'tI. 1.i7J43t. F ,oo,. , F17i [ !i ...
The theory that the αβ dimer is the functional unit of cooperativity in hemoglobin has been tested by determination of the oxygen equilibrium curve of stable deoxy dimers, obtained by...Full Text Available
Non-invasive methods are described for estimating local cerebal blood flows (LCBF) and local partition coefficients (Llambda) during inhalation of 30 % stable xenon gas (Xe) in oxygen during CT scanning. After the denitrogenation with pure oxygen breathing, 30 % Xe is inhaled for four minutes to minimize subanesthetic effects with a rubber facemask and the delivery system of Xe. Local time-..delta.. Hounsfield units curve during the Xe wash-in and wash-out phase is utilized in order to calculate Llambda and LCBF using a least squares curve fitting analysis. Calculated Llambda and LCBF with the new method manifested reasonable distribution between the grey and white matters, and reproducibility was excellent in our study. Several case studies of patients with cerebral infarction are presented to demonstrate the characterization of Llambda and LCBF patterns in various tissues and theoretical grounds underlying the new method of ...
Non-invasive methods are described for estimating local cerebal blood flows (LCBF) and local partition coefficients (L#lambda#) during inhalation of 30 % stable xenon gas (Xe) in oxygen during CT scanning. After the denitrogenation with pure oxygen breathing, 30 % Xe is inhaled for four minutes to minimize subanesthetic effects with a rubber facemask and the delivery system of Xe. Local time-#DELTA# Hounsfield units curve during the Xe wash-in and wash-out phase is utilized in order to calculate L#lambda# and LCBF using a least squares curve fitting analysis. Calculated L#lambda# and LCBF with the new method manifested reasonable distribution between the grey and white matters, and reproducibility was excellent in our study. Several case studies of patients with cerebral infarction are presented to demonstrate the characterization of L#lambda# and LCBF patterns in various tissues and theoretical grounds underlying the new method of ...
A novel approach to the Bragg curve spectroscopy is utilized to construct a charged particle detector which makes fragment elemental identification and energy measurement possible. The advantage of the construction includes good timing and spectroscopic properties with a very low energy threshold. ((orig.))
Typical aircraft types supported include F4-Phantom, Tornado, MiG-29 ...... attempt to develop a theoretical explanation for learning phenomena [16]. ..... perspective, a primary reason for this is that an exponential curve approximates ...
Background and Aim: The purpose of this study was to establish for the first time reference curves for body fat levels in a Greek pediatric population aged 7-15y.Methods:...Full Text Available
The purpose of this study was to evaluate the usefulness of dynamic MRI for femoral head perfusion. Objects were 64 femoral heads of 44 normal cases (20-95 years old), 10 cases (33-90 y) of femoral neck fracture and 8 cases (61-86 y) using steroid due to articular rheumatism, nephrosis and other diseases. Siemens 1.0 T Magneton Impact with body array coil was used for dynamic MRI by the fast low-angle shot 2D method for every 17 sec interval. Gd-DTPA was injected intravenously. ROI was defined in the center of femur head and of trochanter to monitor their values for the dynamic curve. Evaluation was done on the ratio of enhancement ratio (ER) in the head/trochanter and on the curve in both heads. In normal cases, the head ER was significantly lower in >60 years old cases. There was neither significant correlation between their head/trochanter ER ratios nor significant difference between their dynamic curves. In fracture ...
Static task intensity–endurance time (ET) relationships (e.g. Rohmert's curve) were first reported decades ago. However, a comprehensive meta-analysis to compare experimentally-observed...Full Text Available
Choice procedures have indicated that the relative reinforcing effectiveness of opioid drugs increases during opioid withdrawal. The demand curve, an absolute measure of reinforcer value, has not been...Full Text Available
The most important developments in gaseous detectors at LNL are reviewed. Some aspects of timing, pulse height and position resolutions of avalanche counters are reported. The experimental work on heavy-ion identification by Bragg curve spectroscopy is summarized.
A highly reliable screening method was developed for the determination of lead in tin plated layers and tin-bismuth plated layers. The contents of lead in the layers of the various samples were determined by inductively coupled plasma optical emission spectrometry. The calibration curve for lead in the tin and tin-bismuth plated layers by using WD-XRF exhibited linear correlation from 130 #mu#g/g to 2070 #mu#g/g. Calibration curve of lead normalized with Pb-L#alpha#/Sn-K#alpha# intensity was more linear, and this method was possible to evaluate very small sample. The calibration curve for lead in the tin plated layers by using ED-XRF was good linearly, but it for lead in the tin-bismuth plated layers was affected by Pb-L#alpha# spectrum and Bi-L#alpha# spectrum overlap each other. It was effective for decreasing affect of Bi-L#alpha# spectrum by using curve fitting method. (author)
the Advanced Distillation Curve, Energy & Fuels, Vol. 22, No. 2, pp. 11041114. http://pubs.acs.org/doi/full/10.1021/ef700562c. Lemmon, E. W., Huber, M. L., ...
Objective: To compare the efficiency of dual energy subtraction and conventional direct digital radiography in signal detecting ability. Methods: 200 plastic balls which were 4 mm in diameter were taken as signals and were placed on a 10 cm thick plastic board and the right upper thorax of a healthy volunteer. The signals were examined by DES and CDR separately and were estimated by 3 radiologists with 5-value-differentiation method. ROC curve analysis was made by ROC kit software. Results: when signals on plastic board were detected by CDR and DES, ROC curve analysis indicated that there was no significant difference (P=0.4851 > 0.05, two-tailed) between the area under the ROC curves of the two methods (Az=0.9931 for CDR and Az=0.9879 for DES). The difference was significant (P=0.0002 <0.01, two-tailed) between the area under the ROC curves of CDR and DES (Az=0.7276 for CDR and Az=0.8561 for ...
subject to a learning curve which should help to lessen the user's time at KSC. An MMSE Payload Handling Fixture has ...... (F4.I ASSlUN IASILlM.ny.CTC I ...
The frequency dependence of the lasing power of a He-Ne laser was studied using the electrooptic effect in a KDP crystal. The gain profile of the power curve was found to differ noticeably between the high-frequency and low-frequency edges. (AIP). (AIP)
Learning curve models have gained widespread acceptance as a technique for analyzing and ...... flight segment in F4 pilots p 163 A91-30966. WILSON, JOHN W . ...
SEG DAVO'24,(F4). 74. IN LARSYS DAVD'i? 75. SE( DAVD 13., (Ft). 76. INl LARSYS jAV) 13 ...... The main premise of the learning curve, or the manufac ...
The chemistries of reactants, plasticizers, solvents and additives in an epoxy paint are discussed. Polyamide additives may play an important role in the absorption of molecular iodine by epoxy paints. It is recommended that the unsaturation of the polyamide additive in the epoxy cure be determined. Experimental studies of water absorption by epoxy resins are discussed. These studies show that absorption can disrupt hydrogen bonds among segments of the polymers and cause swelling of the polymer. The water absorption increases the diffusion coefficient of water within the polymer. Permanent damage to the polymer can result if water causes hydrolysis of ether linkages. Water desorption studies are recommended to ascertain how water absorption affects epoxy paint.
...Species - see CITES Trade of Dangerous Chemicals Transport and Environment U Urban Environment Use of natural resources V Volatile Organic Compounds W Waste Landfills Waste electrical and electronic equipment - see WEEE Waste incineration Waste legislation - reporting Waste management planning Waste oils Waste shipments Waste water - see Urban waste waterWater Bathing Water Drinking water Floods Marine environment Urban waste waterWater Framework Directive WEEE - Waste Electric and Electronic Equipment Wildlife ...
The laminar incompressible hydrodynamically fully developed and thermally developing flow is studied in a curved square duct with four longitudinal fins. The duct is successively subjected to constant wall temperature, to circumferentially uniform temperature and axially linearly or exponentially varying temperature. The local and fully developed Nusselt numbers are examined for various values of the Dean number and it is found that the heat transfer rate increases for high fins. The parameters that affect the entry length are studied and the fluctuations of the local Nu that appear in the entrance region are investigated. Temperature contour plots are presented for the visualization of the temperature field and functional relations for the Nusselt number are proposed in terms of the Dean and Prandtl numbers. (orig.)
The magnon dispersion curve of Gd metal has been determined from first principles by use of augmented-plane-wave energy bands and wave functions. The exchange matrix elements I (k,k') between the 4f electrons and the conduction electrons from the first six energy bands were calculated under the assumption of an unscreened Coulomb interaction. The results are in good overall agreement with experiment provided the I (k,k') are diminished by a constant scale factor of about 2 which may be caused by screening.
Survival curves were constructed from dose-incidence curves for apoptosis in the crypts of mouse small intestine, using the number of apoptotic cells after high doses (N{sub M}) as maximum cell population size. The mean lethal doses (D{sub 0}) for the dose range 0-0.5 Gy were calculated for each time of day. A circadian rhythm in both D{sub 0} and N{sub M} values was detected, indicating that both the number and sensitivity of radiation-induced apoptosis were changing throughout the day. (author).
We obtain the T-duality transformations of space-time spinors (the supersymmetry transformation parameters, gravitinos and dilatinos) of type-II theories in curved backgrounds with an isometry. The transformation of the spinor index is shown to be a consequence of the twist that T-duality introduces between the left- and right-moving local Lorentz frames. The result is then used to derive the T-duality action on Ramond-Ramond field strengths and potentials in a simple way. We also discuss the massive IIA theory and, using duality, give a short derivation of 'mass'-dependent terms in the Wess-Zumino actions on the D-brane world-volumes.
The aim of this paper is to investigate the total ionizing dose (TID) radiation effects on MOS capacitor with nitride/oxide stack gate. The stack gate MOS capacitors are fabricated with 20 nm oxide, 40 nm nitride or 110 nm nitride respectively. Through the analysis of CV curve of the irradiation capacitors, it is found that the degradation of the CV curve is due to a significant increase of interface traps and somewhat smaller oxide charge. It is also shown that the thicker of the nitride, more interface traps and oxide charge will be occurred. (authors)
A car-borne NaI(Tl) spectrometric system was used together with a {sup 137}Cs source to obtain realistic data in the search for unshielded and semi-shielded orphan sources. The potassium-stripped counts (PSC) method was used to estimate the influence by the shielding on the detection ability. A reduction of about 5% in the critical distance was obtained for the semi-shielded source. A curve fitting method was also developed and evaluated. Results from the curve fitting method showed inferior ability to find the source compared to the PSC method. However, it can be a useful complementary tool, for characterisation of the source shielding, and estimation of the distance from the road.
A car-borne NaI(Tl) spectrometric system was used together with a "1"3"7Cs source to obtain realistic data in the search for unshielded and semi-shielded orphan sources. The potassium-stripped counts (PSC) method was used to estimate the influence by the shielding on the detection ability. A reduction of about 5% in the critical distance was obtained for the semi-shielded source. A curve fitting method was also developed and evaluated. Results from the curve fitting method showed inferior ability to find the source compared to the PSC method. However, it can be a useful complementary tool, for characterisation of the source shielding, and estimation of the distance from the road.
The Bragg Curve Spectrometer (BCS) is an ionization chamber long enough to stop particles of interest. Particles enter through the cathode window and leave an ionization track parallel to the electric field. The ionization electrons drift through a Frisch grid and are collected on an anode. The anode current, as a function of time, is split and used as input for two amplifiers, one with a long integration time constant for energy measurement, and one with a short time constant to pick off the maximum ionization or Bragg peak. The Bragg peak, which is proportional to the nuclear charge, is used for particle identification. We have constructed and tested several versions of the BCS. The results are described.
The Bragg Curve Spectrometer (BCS) is an ionization chamber long enough to stop particles of interest. Particles enter through the cathode window and leave an ionization track parallel to the electric field. The ionization electrons drift through a Frisch grid and are collected on an anode. The anode current, as a function of time, is split and used as input for two amplifiers, one with a long integration time constant for energy measurement, and one with a short time constant to pick off the maximum ionization or Bragg peak. The Bragg peak, which is proportional to the nuclear charge, is used for particle identification. We have constructed and tested several versions of the BCS. The results are described.
A practical method to determine the ionic diffusion coefficient and activation energy by using quasielastic light scattering (QELS) is presented. It is shown that a temperature dependence curve of the QELS intensity at a fixed frequency can be well fitted by Jonscher's formula and that the diffusion parameters can be obtained from this curve fitting. This method is successfully applied not only to crystals with high optical quality, as reported earlier, but also to opaque ceramics, which are more important than the crystals from a practical point of view. The composition dependence of the ionic diffusion coefficient is studied in sintered YbSZ to show the usefulness of this method.
A computerised glow curve deconvolution (CGCD) analysis was applied to the main dosimetric peak of #alpha#-Al_2O_3:C in order to study the effects of light on the glow curve shape. It was shown that both the light-induced signal and the light-induced fading effects tend to shift the main dosimetric peak to higher temperatures and at the same time change its shape. Furthermore it was confirmed that the magnitude of the light-induced signal depends on radiation history and, by increasing the duration of light exposure, the magnitude of the light-induced signal reaches a plateau, thereby implying the saturation of the phototransfer process. (author).
We propose a new approach to study Koszul cohomology of general $g^r_d$'s on general curves via degenerations and deformations. As an application of this new method, we prove projective normality for general line bundles $L$ on general curves with $h^1(L)\\le1$ and degree greater than roughly $(5/4)g$. This improves the bound in a classical theorem of Green and Lazarsfeld. Also we give some partial results on vanishing of higher syzygies for line bundles with $h^1(L)=1$.
This research investigates the impact of national culture and several institutional factors on the safety performance of society and establishes statistically significant relationships between those variables. As expected, the research results reveal that some cultural variables such as uncertainty avoidance, gender orientation and institutional variables such as the degree of law avoidance can directly influence the safety performance of the society. The findings also support the inverted u-curve (Safety Kuznet curve) hypothesis indicating even if we expect a negative trend at the beginning stage of industrialization, we can expect a positive trend in safety performance as their income level continues to improve beyond a certain point.
A conical Bragg-curve spectrometer (BCS) has been constructed. The outer case was a molded plastic cone. Printed circuit techniques were used to form an insert with inscribed equipotentials to approximate a 1/r/sup 2/ electric field shape. The charge and energy resolution were measured for elastically scattered beams of 206 MeV /sup 28/Si, 413 and 378 MeV /sup 56/Fe, and 670 MeV /sup 86/Kr ions. Performance of this detector, particularly its charge resolution, is discussed with respect to variation in solid angle.
New industrial Non Destructive Testing requires the development of new probes: technologies such as high spatial resolution probes for small breaking flaws detection or flexible probes for complex curved surfaces inspection. The CEA/LIST has designed and integrated 2 probes to answer industrial's constraints. The first one is based on Giant Magneto-Resistance and is able to detect 50 ?m3 flaws. The second one is based on micro-coils etched on kapton and its flexibility is adapted to curved surfaces inspection. Both are multi-elements probes, allowing fast inspection. This paper presents those new probes, their design and their performances.
SO/sub 2/ concentrations in the Stuttgart air have been measured continuously since 1965. The two measuring points were located at the bottom of the Stuttgart city basin and 900 m east on the side of one of the surrounding hills. Long-term curves of pollutant loads have been established in consideration of meteorological parameters, as well as curves showing the average daily, weekly, and yearly pollution. The information thus gained may help to plan air pollution abatement measures in city planning.
A novel way to extract relevant parameters associated with the outgoing ions from nuclear reactions, obtained by digitizing the signals provided by a Bragg curve spectrometer (BCS) is presented. This allowed the implementation of a more thorough pulse-shape analysis. Due to the complexity of this task, it was required to take advantage of new and more powerful computational paradigms. This was fulfilled using a back-propagation artificial neural network (ANN) as a pattern identifier. Over training of ANNs is a common problem during the training stage. In the performance of the ANN there is a compromise between its size and the size of the training set. Here, this effect will be illustrated in relation to the problem of Bragg Curve (BC) identification. (Author)
The three determination methods of alpha activity ration are described, namely geometric progression method, extrapolation method and curve fitting method. The validity of the geometric progression method is demonstrated in the present work. The "2"3"8Pu/("2"3"9Pu + "2"4"0Pu) evaluated by extrapolation method is compared with that by geometric progression method. Also, the "2"3"8Pu/("2"3"9Pu + "2"4"0Pu)evaluated by curve fitting method is compared with that by geometric progression.
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)
A large acceptance, high stopping power Bragg curve spectrometer has been developed for use in coincidence experiments with heavy ions. The electron collection fields are radial and position information is obtained from a resistive anode. The detector is 60 cm deep and operates at pressures of up to 2.5 atm of P-10 gas. It is mated to a scattering chamber which allows it to be moved out of plane during coincidence measurements. Factors affecting the performance of the detector are discussed, and results obtained with the detector are presented. (orig.).
A large acceptance, high stopping power Bragg curve spectrometer has been developed for use in coincidence experiments with heavy ions. The electron collection fields are radial and position information is obtained from a resistive anode. The detector is 60 cm deep and operates at pressures of up to 2.5 atm of P-10 gas. It is mated to a scattering chamber which allows it to be moved out of plane during coincidence measurements. Factors affecting the performance of the detector are discussed, and results obtained with the detector are presented. (orig.).
It has been reported by the present authors that behavior of tritium release from solid breeder grain is consisted of diffusion in grain, tritium transfer at surface layer and surface reactions on grain surface such as adsorption or isotope exchange reactions. Tritium release curves estimated using the tritium release model gave good agreement with observed tritium release curves from Li{sub 4}SiO{sub 4}, Li{sub 2}ZrO{sub 3} or LiAlO{sub 2}. Tritium release behavior from Li{sub 2}TiO{sub 3} under humid purge gas, dry purge gas and dry purge gas with hydrogen conditions is discussed in this study, tritium release curves using the release model that we proposed previously give a good agreements with experimental tritium release curves. Tritium effective diffusivity in the crystal grain of Li{sub 2}TiO{sub 3} is also estimated in this study using a curve-fitting method applied to the ...
It has been reported by the present authors that behavior of tritium release from solid breeder grain is consisted of diffusion in grain, tritium transfer at surface layer and surface reactions on grain surface such as adsorption or isotope exchange reactions. Tritium release curves estimated using the tritium release model gave good agreement with observed tritium release curves from Li_4SiO_4, Li_2ZrO_3 or LiAlO_2. Tritium release behavior from Li_2TiO_3 under humid purge gas, dry purge gas and dry purge gas with hydrogen conditions is discussed in this study, tritium release curves using the release model that we proposed previously give a good agreements with experimental tritium release curves. Tritium effective diffusivity in the crystal grain of Li_2TiO_3 is also estimated in this study using a curve-fitting method applied to the release curves obtained ...
The Kyoto Protocol attempts through political negotiations to guide participating industrialized countries' greenhouse gas (GHG) emissions from a positive growing trend, to reach a peak point (or turning point), and then be reduced to a negative growth. That means the relationship between decreasing GHG emissions and economic growth may be described by an inverted-U curve (or called a bell-shaped curve), which is consistent with the concept of the Environmental Kuznets Curve (EKC) hypothesis. This research observed that the economic development and GHG emissions in Economies in Transition (EITs) exhibit a hockey-stick curve trend (or called quasi-L-shape curve), that also generates a lot of 'hot air' which is significant to the implementation of the Kyoto Protocol. In addition, through the analysis of single-country time series data and GDP data, this ...
The Kyoto Protocol attempts through political negotiations to guide participating industrialized countries' greenhouse gas (GHG) emissions from a positive growing trend, to reach a peak point (or turning point), and then be reduced to a negative growth. That means the relationship between decreasing GHG emissions and economic growth may be described by an inverted-U curve (or called a bell-shaped curve), which is consistent with the concept of the Environmental Kuznets Curve (EKC) hypothesis. This research observed that the economic development and GHG emissions in Economies in Transition (EITs) exhibit a hockey-stick curve trend (or called quasi-L-shape curve), that also generates a lot of 'hot air' which is significant to the implementation of the Kyoto Protocol. In addition, through the analysis of single-country time series data and GDP data, this ...
This report is a summary of the contribution of nitrogen and phosphorus in the eutrophication process of inland and coastal waters. Special attention was paid to the mechanisms of these nutrients in regulating biological processes and to the methods available in estimating their effects in the eutrophication of water bodies. The report includes five chapters which are entitled: Introduction, which is a general background to the subject with special attention to the requirements of the Finnish Water Act. Phosphorus and nitrogen as factors regulating biological processes. The topics included are: definition of eutrophication, forms of phosphorus and nitrogen and their sources to inland and coastal waters, effects of these nutrients as growth factors of phytoplankton and macrophytes and consequences of eutrophication. Estimation of the effects of phosphorus and nitrogen. The topics discussed from the point ...
This procedure describes the formulation and make-up of Simulated Dilute Water (SOW), a low-ionic-content water to be used for Activity E-20-50, Long-Term Corrosion Studies. This water has an ionic content which is nominally a factor of ten higher than that of representative waters at or near Yucca Mountain. Representative waters were chosen as J-13 well water [Harrar, 1990] and perched water at Yucca Mountain [Glassley, 1996]. J-13 well water is obtained from ground water that is in contact with the Topopah Spring tuff, which is the repository horizon rock. The perched water is located in the Topopah Spring tuff, but below the repository horizon and above the water table. A nominal times ten higher ionic content was chosen to simulate the effect of ionic ...
The study investigates the possibility of enhancing crop water productivity in the parts of Northwest India where groundwater quality is marginal and canal water supply is severely scarce. Soil, Water, Atmosphere and Plant (SWAP) model was calibrated and validated in three farmers' fields with varying canal water availability and groundwater quality in the Kaithal Irrigation Circle of the Bhakra Canal system, Haryana. On the basis of predicted and observed soil water content, pressure heads, salt concentration at 2 week intervals and crop yields, the model was found suitable for use in the region. A few nomographs were prepared to provide a graphical method to predict the effect of different combinations of water quality and depth of water application on crop yield and soil salinity and to...
The research committee of the Atomic Energy Society of Japan on water chemistry standard aims at establishing the private standard of water chemistry of nuclear power plants. The committee gathers up 'BWR water chemistry management manual', 'PWR primary system water chemistry management manual' and 'PWR water chemical analysis standard method', and furthermore aims at the standardization of those in future. Looking back on the committee's activities for the past four years, latest results of research of water chemistry mainly contributing to safe and reliable nuclear power plants were described with the future perspective of water chemistry and a demanded break-through. (T.T.)
Using the Laser-Fluorescence technique, an investigation was made, adopting the standard mix method, on trace uranium concentrations in hot spring water and geothermal water from Lishan region, and in tap water from some major cities in Shanxi province. Totally 40 samples from 27 sites were investigated. Measurement showed that the tap water contains around 10"-"6 g/L of uranium, whose concentrations in both hot spring water and geothermal water are 10"-"5 g/L. Most of samples are at normal radioactive background level, some higher contents were determined in a few samples
In equipment industries, the equipments handling industrial water and pure water are numerous. In power generation including nuclear power generation, water serves as a working medium. Review is made on the experiences in the corrosion of iron and nickel base alloys in high temperature, high pressure water and the results of researches derived from them. Under high temperature and high pressure, carbon steel, low alloy steel, stainless steel and high nickel alloy cause corrosion even in pure water. But in the case of serious corrosion, chlorine, oxygen, alkali and others in water take part. The following matters are described: corrosion by steam; stress corrosion cracking in pure water; corrosion by impurities in high temperature, high pressure pure water, i.e. chlorine ions, dissolved oxygen, and alkali; corrosion under ...
...AquaMagna Water Conditioner and Descaler OCETA Environmental Technology & Business Profiles AQUAMAGNA WATER CONDITIONER AND DESCALER CAT. #03-018 CONTACT: Magna-Tek ...removal high-strength ceramic magnet no energy input The AquaMagna Water Conditioner and Descaler is a non-chemical method of water treatment. The technology uses ... Figure 1: The AquaMagna Water Conditioner and Descaler PROCESS/ PRODUCT APPLICATION: hard water domestic water process water reverse osmosis heat exchangers cooling ... For once-through or recirculating heating or cooling equipment, the AquaMagna descaler improves thermal efficiencies and reduces downtime. Figure 2 illustrates a cross-section ...
This paper presents a novel domestic hot water heater model to be used in a multi-objective demand side management program. The model incorporates both the thermal losses and the water usage to determine the temperature of the water in the tank. Water heater loads are extracted from household load data and then used to determine the household water usage patterns. The benefits of the model are: (1) the on/off state of the water heater and temperature of the water in the tank can be accurately predicted, and (2) it enables the development of water usage profiles so that users can be classified based on usage behaviour. As a result, the amount of ancillary services and peak shaving that can be achieved are accurately predictable and can be maximized without adversely affecting users. (author)
...Tota-MaharajE-Mail: Interests: water and wastewater treatment, environmental engineering and sustainable systems; sustainable water management; sustainable urban drainage systems (SUDS); combined renewable energy applications with reverse osmosis desalination; microbial fuel cells for bioenergy production and treatment of urban wastewater; solar photocatalytic treatment and disinfection of water/wastewater Dr. Simon Toze CSIRO Land and Water, Queensland Bioscience Precinct - St Lucia, 306 Carmody Road, St Lucia QLD 4067,...
Indicators of source water use in different economic branches, water consumption in recycling and recycling-successive water supply in 1980?2006 are analyzed. Trends were identified in variations in specific water consumption in industry, agriculture, and municipal economy. Territorial differentiation of wetness indicators of regional product over federal districts and constituent territories of the RF is shown. Wetness values of gross domestic product in different economies are compared.
Measurements of the retention of /sup 47/Ca and of /sup 203/Pb were made following their administration by intravenous injection. Translocation to bone was measured by ..gamma.. counting the feet of subjects. Uptake by bone of /sup 203/Pb was comparatively slow and extrapolation to the whole skeleton indicated that 20% of the dose has been taken up within 20 days. By time, a similar fraction of the dose has been excreted in urine. Uptake by bone of /sup 47/Ca was about 1.5-2 times the amount excreted in urine. Both the uptake by bone, and its excretion in urine, were more rapid than that of /sup 203/Pb due to the greater attachment of the latter to red blood cells. However, the plasma clearance rate for Pb, like that of Sr, was greater than that of Ca.
Purpose - To sustain competitive advantage, it is necessary to understand consumers and their psychological fears and deliver them a service solution which is best under existing conditions so as to ensure consumer loyalty and retention. This paper seeks to conceptualise and operationalise customer relationship management (CRM) through two component model (operational CRM (OCRM) and analytical CRM (ACRM)), particularly in the healthcare sector. Design/methodology/approach - The relationship between OCRM, based on three patient-staff constructs (physicians, nurses and support staff) and ACRM based on four constructs (satisfaction, repatronization, recommendation and organizational performance) was analysed using confirmatory factor analysis (AMOS). The data for the model were collected from...
Knowledge and awareness of past and future autobiographical events may be mediated by a common system that supports intentional, goal-directed behavior. The purpose of this study was to assess the correspondence of past and future autobiographical thought. In Experiment 1, 300 undergraduates aged 19 years generated and assigned dates to past and f utu re autobiographical events. Thetemporal distribution of past events replicated a power function for retention as has been described in past research. The intention function of future autobiographical events fit the inverse of this same power function, reflecting a temporality of past and future mental time travel centered around the present moment. In Experiment 2, these findings were extended to young, middle-aged, and older groups. These data provide empirical support for the notion that thinking outside of "now" is mediated by a common system, regardless of whether one is thinking about the past or the future. ...
Los Alamos National Laboratory (LANL) and the University of California, San Diego (UCSD) have taken the unprecedented step of creating a collaborative, multi-disciplinary graduate education program and associated research agenda called the Engineering Institute. The mission of the Engineering Institute is to develop a comprehensive approach for conducting LANL mission-driven, multidisciplinary engineering research and to improve recruiting, revitalization, and retention of the current and future staff necessary to support the LANL' s national security responsibilities. The components of the Engineering Institute are (1) a joint LANL/UCSD degree program, (2) joint LANL/UCSD research projects, (3) the Los Alamos Dynamic Summer School, (4) an annual workshop, and (5) industry short courses. This program is a possible model for future industry/government interactions with university partners.
The dimercaptosuccinic acid metronidazole ester (DMSAMe) was synthesized and radiolabeled with 99mTc to form the 99mTc-DMSAMe complex in high yield. The radiochemical purity of the 99mTc-DMSAMe complex was over 90%, as measured by TLC and by HPLC, without any notable decomposition at room temperature over a period of 6?h. Its partition coefficient indicated that it was a lipophilic complex. The tumor cell experiment and the biodistribution in mice bearing S 180 tumor showed that the 99mTc-DMSAMe complex had a certain hypoxic selectivity and accumulated in the tumor with high uptake and good retention. The tumor/blood and tumor/muscle ratios increased with time, suggesting it would be a possible tumor hypoxia imaging agent.
Cu(II)-ATSM continues to be investigated, both in the laboratory and in the clinic, as a tumor hypoxia imaging agent. However, meaningful interpretation of these images requires a more complete understanding of the mechanism by which the tracer is trapped within the cell. Cu(II)-ATSM is a simple molecule and its biochemical interaction with cells is similarly simple, mainly based upon redox chemistry. Here we suggest that the trapping mechanism is biphasic. The first phase is a reduction/oxidation cycle involving thiols and molecular oxygen. This can be followed by interaction with proteins in the mitochondria leading to more permanent retention of the tracer. The uptake mechanism is complicated by this second step because of the changes in the cell resulting from hypoxia, such as an incre...
Abstract This study was undertaken over a 10-month period under environmental conditions within the state of Mato Grosso, Brazil, to evaluate the causes of variation in the technological and thermal properties of raw natural rubber (NR) from different clones of Hevea brasiliensis (GT 1, PR 255, FX 3864, and RRIM 600). These clones were chosen to represent good clones available in Brazil. The technological properties of raw NR were evaluated in terms of their dry rubber content (DRC), Wallace plasticity, plasticity retention index (PRI), and Mooney viscosity. The thermal performance was evaluated with the thermogravimetry (TG)/differential thermogravimetry (DTG) technique. There were significant variations (p < 0.01 and p < 0.05) between clones and tappings for all technological properties,...
Wood-plastic composite (WPC) formation has been studied with simul + styrene system at various compositions of styrene with methanol as the swelling solvent. Effect of additives, e.g. multifunctional monomers (MFM)and oligomers used in very low quantity (1% v/v) on the polymer loading (PL) and tensile strength (TS) of the WPC has been elaborately investigated. Enhanced PL and TS values are observed. Inorganic co-additives like Lithium (Li"+), Copper (Cu"2"+) and acid (H"+) and urea (U) used in combinations with additives (MFM or oligomers) have influenced the results of PL and TS in these systems. Li"+ ion has been a good replacement for H"+ ion; U has substantially enhanced the PL values with retention of the TS values of WPC. Co-additive Cu"2"+ used in these systems can act as a preservative and protective agent for WPC. (Author).
All measurements were made with the NBS high-pressure photoionization mass spectrometer. The fractional of C/sub 5/H/sub 10//sup +/ions in a cyclopentane-cyclohexane mixture were determined as a function of pressure in order to define the fraction of the ions which did charge exchange with cyclohexane; i.e. the fraction which remained cyclic after ionization. The data for mixtures of various compositions (2.5 to 10% cyclohexane) are summarized for measurements performed at 10.62 eV: (a) 292K, > 96% cyclic; 347 K, greater than or equal to 94% cyclic; 386 K, 84 +- 4% cyclic; and 412 K, 78 +- 6% cyclic; entropy, enthalpy, and activation energy were determined; 10.49 eV was obtained as the ionization potential of cyclopentane. 1 figure.
A series of four 125I-labeled 1-substituted-4-phenylpiperazines were prepared and evaluated in rats as potential brain imaging agents. The compounds were labeled using (125I)iodide/chloramine-T or iodine monochloride and isolated in 48-60% radiochemical yields. The tissue distribution studies indicated that a butyrophenone derivative demonstrated the best overall brain-imaging properties. Compared with the compounds having other 1-substituents this agent had a more prolonged retention of activity in the brain and higher brain-to-blood ratios over the 4-h period studied. The in vivo behavior of this agent is comparable to that of radioiodinated N-isopropyl-p-iodoamphetamine, and, because it can be labeled directly via electrophilic methods, it has substantial potential for use in brain imaging with single photon emission computed tomography.
This paper describes new strategies for the brain-specific delivery of radionuclides that can be used to evaluate regional cerebral perfusion by single photon imaging techniques. A description of several examples of interesting new strategies that have recently been reported is presented. A new approach at this institution for the brain-specific delivery of radioiodinated iodophenylalkyl-substituted dihyronicotinamide systems is described which shows good brain uptake and retention in preliminary studies in rats. Following transport into the brain these agents appear to undergo facile intracerebral oxidation to the quaternized analogues which do not recross the intact blood-brain barrier and so are effectively trapped in the brain. 49 refs., 9 figs., 1 tab.
The goals of this paper are to describe new strategies being pursued at several institutions for the brain-specific delivery of radionuclides that can be used to evaluate regional cerebral perfusion by single photon imaging techniques. A comprehensive review of the literature is beyond the scope of these proceedings and our goal is to, therefore, present a description of several examples of interesting new strategies that have recently been reported. In addition, the authors also describe a new approach being pursued at their institution for the brain-specific delivery of radioiodinated iodophenylaklyl-substituted dihydronicotiamide systems which shows good brain uptake and retention in preliminary studies in rats. Following transport into the brain these agents appear to undergo facile intracerebral oxidation to the quaternized analogues which do not cross the intact blood-brain-barrier and are effectively trapped in the brain.
The present study was carried out to exploit the feasibility of using polymeric nanosponges as an alternative carrier for targeting econazole nitrate (EN) to the skin through topical hydrogel formulation. Nanosponges prepared by emulsion solvent diffusion method were evaluated for various physicochemical parameters and in vitro drug release. The nanosponges of EN were discrete free flowing nanosized particles with perforated orange peel like morphology as visualized by SEM. The nanosponge formulated using PVA:EC (3:2) displayed highest in vitro release after 12 ?h in phosphate buffer (pH 6.8) that fitted matrix model. Selected nanosponge was formulated as Carbopol 934 NF hydrogel using varying concentrations of permeation enhancers propylene glycol and N-methyl-2-pyrrolidone. The EN nanosp...
The relevance of the mean retention time (MRT) of particles through the gastrointestinal tract (GIT) is well understood and MRTparticleGIT is an important parameter in digestion models. Solute markers have been used to estimate MRTsoluteGIT (or 'fluid passage') in animals, but the relevance of this measure is less evident and is usually sought in its relation to MRTparticleGIT. The ratio between the two measures indicates the degree of 'digesta washing', with little washing occurring at ratios of 1, aborad washing at ratios >1 (where the solute marker travels faster than the particle marker), and orad (retrograde) washing at ratios <1 (where the solute marker travels slower than the particle marker). We analysed digesta washing in a dataset of 98 mammalian species including man of differen...
The US Department of Energy (DOE) has millions of gallons of high level nuclear waste stored in underground tanks at Hanford, Washington and Savannah River, South Carolina. These tanks will eventually be emptied and decommissioned. This will leave a residue of sludge adhering to the interior tank surfaces that may contaminate groundwaters with radionuclides and RCRA metals. Experimentation on such sludges is both dangerous and prohibitively expensive so there is a great advantage to developing artificial sludges. The US DOE Environmental Management Science Program (EMSP) has funded a program to investigate the feasibility of developing such materials. The following text reports on the success of this program, and suggests that much of the radioisotope inventory left in a tank will not move out into the surrounding environment. Ultimately, such studies may play a significant role in developing safe and cost effective tank closure strategies.
A polymer-based additive that permanently reduces hardness in wood electrical transmission poles treated with a chromated copper arsenate (CCA) preservative, has been developed by a team of IREQ researchers. A three-phase project is being funded by Hydro-Quebec to evaluate the additive's effect on full-size hydro poles subjected to actual climatic conditions. The evaluation project is designed to test the CCA and the additive's degree of retention by analyzing the hardness measurements against climbing tests, and the washing resistance of the chromium, copper and arsenate in the CCA/polymer-additive treatment. CCA-treated poles will be used for reference. Accelerated aging tests to characterize the polymer's resistance to UV rays will also be part of the validation program.
Morphology of castellated Be tiles from the belt limiter exposed to the JET plasma for 56,000 s was examined on both sides of castellated grooves, on plasma-facing and side surfaces of the tiles. The essential results are (i) deuterium retention in the castellated grooves and in other locations is associated with co-deposition of carbon; (ii) the decay length of deposition in the castellation is around 1.5 mm; (iii) no deuterium is detected in bulk Be; (iv) bridging of gaps by molten beryllium occurred but gaps were not filled with Be; (v) on side surfaces of the tiles the formation of BeO layer was detected at a distance of 20 mm and more from the plasma-facing surface. The consequences for a long-term operation of a reactor-class device with several different plasma-facing materials are addressed.
This article presents an orthognathic treatment case after severe apical root resorption of maxillary anterior teeth using anterior segmental osteotomy. This case involved a 20-year-old female with the chief complaint of maxillary protruding and irregularly aligned mandibular anterior teeth. Her medical history showed no allergies or medical problems. The overbite was +3.0mm, and the overjet +3.0mm. After extraction of the four first premolars, a multi-bracket treatment was started. A severe root resorption of the maxillary anterior teeth was found 12 months after active treatment. The maxillary anterior segmental osteotomy was chosen as the compensatory treatment. The total treatment period was 2 years and 7 months. The post-retention panoramic radiograph showed no developmental root reso...
This paper presents a numerical study on the formation history of coalbed methane (CBM) reservoir in the southeast edge of Ordos Basin, China. The coal seams studied belong to the Late Palaeozoic coal-bearing series. These coal seams have a burial history and experienced the process of subsidence, rapid subsidence alternated with uplift and then uplift, sequentially, and underwent the geothermal actions at normal, extremely high, and then normal temperatures, respectively. Coal organic matter of the coal seams matured in the Triassic Period and in the Late Jurassic to Early Cretaceous Period. The results from numerical simulation reveal that CBM reservoir evolution history can be classified into five stages, namely primary, initial, stagnant, active and dissipative stages. In the first (pr...
Lipophilic tertiary amines attached to cylcopentadienyl technetium-99m tricarbonyl (cytectrene) have been prepared with high radiochemical yield and purity. Biodistribution studies in mice showed that [{sup 99m}Tc]-cytectrenes, containing in their structure an N-methylpiperidine, were accumulated in the brain up to 2.8% of injected dose with high brain-to-blood ratios at 15 min p.i. They therefore indicate some potential as brain imaging agents. It has to be pointed out that the N-methylpiperidine ester showed similar biological behaviour as the keto derivatives. This indicates that the conversion to polar metabolite(s) via hydrolysis of the ester group - as described for [{sup 99m}Tc]-ECD -is not essential for brain retention. (Author).
Lipophilic tertiary amines attached to cylcopentadienyl technetium-99m tricarbonyl (cytectrene) have been prepared with high radiochemical yield and purity. Biodistribution studies in mice showed that ["9"9"mTc]-cytectrenes, containing in their structure an N-methylpiperidine, were accumulated in the brain up to 2.8% of injected dose with high brain-to-blood ratios at 15 min p.i. They therefore indicate some potential as brain imaging agents. It has to be pointed out that the N-methylpiperidine ester showed similar biological behaviour as the keto derivatives. This indicates that the conversion to polar metabolite(s) via hydrolysis of the ester group - as described for ["9"9"mTc]-ECD -is not essential for brain retention. (Author).
The thermodynamic characteristics of adsorption (TCA) on the basal face of graphite have been calculated in terms of the semiempirical molecular statistical theory of adsorption for molecules of O-, S-, and Se-containing heteroadamantanes of different structure and isostructural cyclohexane derivatives. The influence of the nature, number, and position of heteroatoms in the adamantane framework on the TCA values was studied in detail, which made it possible to predict the retention of the compounds considered on the surface of graphitized thermal carbon black under the conditions of equilibrium gas adsorption chromatography. The introduction of each subsequent heteroatom into a polyheteroadamantane molecule makes a non-additive contribution to the TCA values. The contributions of various f...
Vaccine-mediated prevention of primary HIV-1 infection at the heterosexual mucosal portal of entry may be facilitated by highly optimised formulations or drug delivery devices for intravaginal (i.vag) immunization. Previously we described hydroxyethylcellulose (HEC)-based rheologically structured gel vehicles (RSVs) for vaginal immunization of an HIV-1 vaccine candidate, a soluble recombinant trimeric HIV-1 clade-C envelope glycoprotein designated CN54gp140. Here we investigated the efficacy of lyophilized solid dosage formulations (LSDFs) for prolonging antigen stability and as i.vag delivery modalities. LSDFs were designed and developed that upon i.vag administration they would reconstitute with the imbibing of vaginal fluid to mucoadhesive, site-retentive semi-solids. Mice were immunize...
The incorporation of additives designed to sacrificially react on the surface of cathode materials of lithium ion batteries has been investigated. Addition of low concentrations of inorganic additives including lithium bisoxalatoborate (LiBOB), lithium difluorooxalatoborate (LiBF{sub 2}(C{sub 2}O{sub 4})), and tetramethoxy titanium (TMTi) to 1 M LiPF{sub 6} in 1:1:1 EC/DEC/DMC improves the capacity retention of Li/Li{sub 1.17}Mn{sub 0.58}Ni{sub 0.25}O{sub 2} cells cycled to 4.9 V vs. Li. Surface analysis of the cathode materials (XPS and IR) suggests that structure of the cathode surface film is modified by the presence of the additives resulting in a decrease in detrimental electrolyte oxidation reactions on the cathode surface. (author)
An aliphatic thiol ligand of CuInS2/ZnS core/shell quantum dots is replaced with a hydroxyl-terminated thiol ligand by utilizing `on-off state' of ligands during growth stage of the quantum dots. After the ligand-exchange, negligible differences were observed on both photoluminescence spectrum and luminescent quantum efficiency. The reason for the high retention of luminescent efficiency comes from no local agglomeration and no surface deterioration of QDs. It is also observed that 70% of initial ligands are exchanged by the replacing ligand, determined by FT-IR and 1H NMR. The proposed method provides the quantum dots with an excellent dispersibility in polar solvents, supported by identical luminescence decay characteristics of the QDs.
Wood usage for cooking and heating is still very relevant in most developing countries especially those of sub-Saharan Africa and many parts of Asia. Therefore, sustainable means of generating it for this and other purposes are necessary bearing in mind the influence of indigenous knowledge/users perspective on any production method regarding success and sustenance. In conformity with this view, questionnaires were administered on 240 respondents in 8 rural communities of Akinyele and Ido Local Government Areas (LGAs) of Oyo State, Nigeria, to elicit information on species that can be used as fuelwood, preferred by the respondents for incorporation into and/or retention in agroforestry plots, out of which 179 (i.e. 75% of the total number of questionnaires administered) were successfully r...
The invention is a mechanism for retaining an electrical transmission line. In one embodiment of the invention it is a system for retaining an electrical transmission line within downhole components. The invention allows a transmission line to be attached to the internal diameter of drilling components that have a substantially uniform drilling diameter. In accordance with one aspect of the invention, the system includes a plurality of downhole components, such as sections of pipe in a drill string, drill collars, heavy weight drill pipe, and jars. The system also includes a coaxial cable running between the first and second end of a drill pipe, the coaxial cable having a conductive tube and a conductive core within it. The invention allows the electrical transmission line to withstand the tension and compression of drill pipe during routine drilling cycles.
Background: This study was conducted to examine the effects of prophylactic misoprostol prior to intrauterine device (IUD) placement in nulliparous women. Study Design: Nulliparous, reproductive-aged women desiring an IUD for contraception were randomized to receive 400 mcg of buccal misoprostol or placebo 90 min prior to IUD insertion. Subjects completed a series of 100-mm visual analogue scales (VAS, anchors: 0=none, 100 mm=worst imaginable) to measure their perceived pain at several times points (anticipated pain, leg positioning, speculum placement, tenaculum placement, IUD insertion, equipment removal and 5 min postinsertion). Secondary outcomes included provider ''ease of placement'' (100-mm VAS, anchors: 0=easy, 100 mm=extremely difficult), side effects and retention of the IUD afte...
An incinerator for the treatment of low-level radioactive solid wastes was installed in Tokai Research Establishment, JAERI, 1966. The incinerator was equipped with a scrubber, cyclone, electrostatic precipitator and HEPA filter. The retention factor (R.F.) of the furnace as well as the decontamination factors (D.F.) of each dust collector were measured using "3"2P as a tracer under various conditions. It was found that the overall D.F. of the incinerator was improved by the increase of the temperature in the furnace, decrease of the off gas flowrate, increase of the charged voltage of the electrostatic precipitator and by the increase of the liquid gas ratio of the scrubber. The overall D.F. of the incinerator (including the R.F. in the furnace) on the standard operating conditions was 9.1x10"6. (auth.).
This work reports a systematic comparative study of the technological properties of natural lattices and rubbers extracted from Hancornia speciosa Gomes and Hevea brasiliensis [(Willd. ex Adr. de Juss.) Muell.-Arg.] (clone RRIM 600) trees from 11 collections in Brazil throughout 2004. Natural rubber latex particle sizes and distributions were quite similar with an average diameter around 1 mm. Molecular weight, Wallace plasticity, and Mooney viscosity values were approximately the same for both rubbers. Fourier transform infrared spectroscopy peaks characteristic of natural rubber were observed for both Hancornia and Hevea. The measured differences in technological properties included lower values for Hancornia dry rubber content, % ash, % nitrogen, and plasticity retention index but highe...
Background, aim, and scope Semi-trailers with load boxes are the most important mode of grain transport by land in the world. Load boxes can be produced with different materials such as: wood, steel, and synthetic material. They are responsible for effectiveness retention and quality of grains during the transport. Among the main aspects to be considered and valued when selecting materials for load boxes are the final mass of the semi-trailer, loss of grains, and mechanical properties. Environmental performance is another important aspect to be taken into account for developing and selecting new materials in this kind of application. This study presents a comparative environmental evaluation of load boxes built from two different materials (a wood panel and a three-layer synthetic (TLS) pa...
Transgenic plants offer advantages for biomolecule production because plants can be grown on a large scale and the recombinant macromolecules can be easily harvested and extracted. We introduced an Aspergillus phytase gene into canola (Brassica napus) (line 9412 with low erucic acid and low glucosinolates) by Agrobacterium-mediated transformation. Phytase expression in transgenic plant was enhanced with a synthetic phytase gene according to the Brassica codon usage and an endoplasmic reticulum (ER) retention signal KDEL that confers an ER accumulation of the recombinant phytase. Secretion of the phytase to the extracellular fluid was also established by the use of the tobacco PR-S signal peptide. Phytase accumulation in mature seed accounted for 2.6% of the total soluble proteins. The enzy...
The solid particle movement in a rotary drum plays an important role in drying processes. The solid distribution in the drum affects the amount of contact surface between the solid and the gas. The retention time of solids influences the time particles can stay in contact with the gas in order to transfer heat and mass. Any heat and mass transfer model for a solid particle dryer must be able to predict solid flowrate and solid hold-up. There have been several reports in the literature regarding the modeling aspects of solid transport in dryers. If the model is developed for model-based control, it must be simple and yet represent dynamics of the system accurately. This paper addresses solid motion modeling and the effects of different variables involved in solid transport phenomena.
In this paper, we propose a bid optimizer for sponsored keyword search auctions which leads to better retention of advertisers by yielding attractive utilities to the advertisers without decreasing the revenue to the search engine. The bid optimizer is positioned as a key value added tool the search engine provides to the advertisers. The proposed bid optimizer algorithm transforms the reported values of the advertisers for a keyword into a correlated bid profile using many ideas from cooperative game theory. The algorithm is based on a characteristic form game involving the search engine and the advertisers. Ideas from Nash bargaining theory are used in formulating the characteristic form game to provide for a fair share of surplus among the players involved. The algorithm then computes the nucleolus of the characteristic form game since we find that the nucleolus is an apt way of allocating the gains of cooperation among the search engine and the advertisers. The ...
Background Microbial water-quality indicators, in high concentrations in sewage, are used to determine whether water is safe for recreational purposes. Recently, the use of these indicators...Full Text Available
The effect of the water-chemical regime (WCR) on damage sustained by heating surfaces of steam generators at NPP is analyzed. It is indicated that phosphate treatment with minimal excesses of phosphates in the steamgenerator water is the most optimal method of managing the WCR regime of horizontal steam generators.
The effect of water stress on patterns of nitrate reductase activity in the leaves and nodules and on nitrogen fixation were investigated in Medicago sativa L. plants watered 1 week...Full Text Available
The reference medium for brachytherapy dose measurements is water. Accuracy of dose measurements of brachytherapy sources is critically dependent on precise measurement of the source–detector...Full Text Available
A model was developed to compute concentration of impurities in the WWER 440 steam generator (SG) secondary water along the tube bundle. Calculated values were verified by concentration values obtained from secondary water sample chemical analysis. (orig.). 2 refs.
A method of measuring the water potential of stored potato tubers (Solanum tuberosum L.) was needed to investigate the relationship of bacterial soft rot in tubers to water potential....Full Text Available
Background and AimsXylem vessels containing gases (embolized) must be refilled with water if they are to resume transport of water through the plant, so refilling is of great importance...Full Text Available
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 ...
Inadequate measures of water quality have been used in many studies of the health effects associated with water supplies in developing countries. The present 1-year epidemiological-microbiological study...Full Text Available