Thermal-hydraulics analysis can be used to determine location and magnitude of leaks inside a pressurized water reactor (PWR) containment, as required by plant technical specifications. The major advantage of this detection method is that it minimizes radiation exposure of maintenance personnel because most of the leakdetection process is performed from the control room outside the containment. In addition, such a program allows for the elimination of pipe whip restraints and jet impingement shields, eliminating costs for maintenance of these supports and shields in older plants and lowering construction costs for new plants. Previously, only simple single-node containment models were used for determining leakage magnitude. This paper presents a more sophisticated multinode approach for determining the magnitude and location. The resulting sensitivities to leak ...
Recent advances in elastic-plastic fracture mechanics have made it possible to assess the stability of cracks in ductile piping systems. These technological developments have been used by Ontario Hydro as the nucleus of an approach for demonstrating that CANDU primary heat transport piping systems will not break catastrophically; at worst they would leak at a detectable rate. This leak-before-break approach has been taken on the Darlington nuclear generating station as a design stage alternative to the provision of pipe whip restraints on large diameter, primary heat transport system piping. Positive conclusions reached via this approach are considered sufficient to exclude the requirement to provide protective devices, such as pipe whip restraints. In arriving at the proposed leak-before-break approach a review of current and proposed leak-before-break licensing positions of other ...
The Steam Generator (SG) serves as an interface between primary and secondary cycle in Pressurized Heavy Water Reactor (PHWR). Failure of steam generator tubes result in leaking of active heavy water in the secondary closed loop. In Tarapur Atomic Power Station-3 and 4 (TAPS- 3 and 4), Scintillator detectors are provided to detect on line heavy water leakages in SG and moderator heat exchangers by monitoring Nitrogen-16 (16N) and Oxygen-19 (19O) activities. Efficacy of detection of these activities at designed detector position on SG blow down line in presence of background radiation field is analysed theoretically. The count rate of 19O and 16N estimated at the detector position inside Reactor Building (RB) shows that detectors only respond to very high leak rates due to presence of high ambient radiation level even though sensitivity is ...
The Candu 6 reactor assembly consists of an array of 380 pressure tubes, which are installed horizontally in a large cylindrical vessel, the Calandria, containing the low pressure heavy water moderator. The pressure tube is located inside calandria tube and the annulus between these tubes, which forms a closed loop with CO{sub 2} gas recirculating, is called the Annulus Gas System (AGS). It is designed to give an alarm to the operator even for a small pressure tube leak by a very sensitive dew point meter so that he can take a preventive action for the pressure tbe rupture incident. To judge whether the operator action time is enough or not in the design of Wolsung 2, 3, and 4, the Leak Before Break (LBB) assessment is required for the analysis of the pressure tube failure accident. In order to provide the required data for the LBB assessment of Wolsung Units 2, 3, 4, a series of leak ...
The Steam Generator (SG) serves as an interface between primary and secondary cycle in Pressurized Heavy Water Reactor (PHWR). Failure of steam generator tubes result in leaking of active heavy water in the secondary closed loop. In Tarapur Atomic Power Station-3 and 4 (TAPS- 3 and 4), Scintillator detectors are provided to detect on line heavy water leakages in SG and moderator heat exchangers by monitoring Nitrogen-16 ("1"6N) and Oxygen-19 ("1"90) activities. Efficacy of detection of these activities at designed detector position on SG blow down line in presence of background radiation field is analysed theoretically. The count rate of "1"9O and "1"6N estimated at the detector position inside Reactor Building (RB) shows that detectors only respond to very high leak rates due to presence of high background even though sensitivity is ...
The W-259 project will provide upgrades to the 2706-T/TA Facility to comply with Federal and State of Washington environmental regulations for secondary containment and leakdetection. The project provides decontamination activities supporting the environmental restoration mission and waste management operations on the Hanford Site.
This report describes a study to evaluate methods for locating leaks of dielectric fluid from buried high-voltage cable systems. Two primary types of leak location systems were investigated: (1) systems that will rapidly isolate the leak within a manhole section, typically 1000-m long on a feeder that might be 30-km long; and (2) systems that will then pinpoint the location of the leak. Rapid leak isolation was accomplished by developing an enhanced conductivity oil probe which allows the injection of a small quantity of conductive oil and which indicates the path of the oil as it drifts downstream in the direction of the leak. Two methods for pinpointing the leak were proven. The more successful method was the use of trained leak location dogs which were found to have far better sensitivity than instruments and which ...
During unit wise conditioning of unit 8, the vacuum started deteriorating inside the tube after a spark. The RGA reading was taken and it was found out that residual gas inside tube was sulphur hexafluoride. A leak was detected in second tube of unit number eight in between electrode 6 to 8. Leak was sealed with the sealant. Again leak check was done and no leak was found. The tank was closed and conditioning was started again. During the same unit number eight conditioning, leak developed again followed by a spark. So the damaged tube was replaced with a new accelerator tube. During the installation time the alignment of the machine was taken care. Again leak checking was done and the tube was baked properly. The tank was closed again and this particular unit was conditioned for about four days. The maximum voltage it has attained was 1.1 ...
Wolsung nuclear power plant has experienced four occasions of reactor shutdown owing to heavy waterleaks since its commercial operation. Among these heavy waterleaks, only one case was acute and brought about reactor shutdown but the other cases listed below were chronic and repaired after manual reactor shutdown. (author). 4 tabs., 10 figs.
It is estimated that more than 180.000 kilometres of onshore pipelines will be installed between now and 2012. According to the US Federal Office of Pipeline Safety report (1968-97), the average pipeline suffers one leak per year every 400 miles. This equates to a total of 180 expected leaks per year for a new pipeline alone. Sensornet's continuous real-time Digital LeakDetection monitoring solution has the reach, precision and the speed to provide complete, continuous real-time knowledge (author)
This paper discusses the remote plugging of leaks in inaccessible pipework, with main reference to small leaks which frequently appear in ancillary cooling water circuits of nuclear reactors. Initially developed to cure problems of the pre-stressed concrete pressure vessels of UK reactors, the ZORIC sealant has been used to repair leaking biological shield pipework on six CANDU reactors. ZORIC is based on a water-soluble epoxy resin and an aqueous suspension of a refined mineral clay. This paper describes the evolution of the sealant, the qualification and testing program, and their application to CANDU reactor systems. 2 refs., 6 figs.
The performance of steam generator tubes in water-cooled nuclear power reactors has been reviewed for 1979. Tube failures occurred at 38 of the 93 reactors surveyed. Causes of these failures and procedures designed to deal with them are described. The defect rate was twice that in 1978 but still lower than the two previous years. Methods being employed to detect defects include increasing use of multifrequency eddy-current testing and a trend to full-length inspection of all tubes. To reduce the incidence of tube failures by corrosion, plant operators are turning to full-flow condensate demineralization and more leak-resistant condenser tubes. (author).
This paper presents a unique method, currently under evaluation, that can continuously track pipeline operation providing essentially instantaneous responses to leaks or ruptures without causing a pressure drop or energy loss. Using the highly linear characteristics of a very accurate and repeatable meter and then correlating it to a second identical unit, a dynamic leakdetection system is planned that can be retrofitted on existing pipelines without a major construction effort nor destroying the integrity of the existing transmission line. Initial tests performed on a crude oil transmission line verified the equipment's performance and established that the repeatability limits are sufficient to continue development of the concept.
Through a comprehensive and aggressive research program Consolidated Edison Company of New York, Inc. (Con Edison) has designed, developed, and installed several new products to address the environmental impact of dielectric fluid from pipe-type cable systems. These include: On Line LeakDetection, Leak Location, Retractable Flow Direction Indicator, Full Stop Joints, and Transition Joints. This paper describes the application of the aforementioned products on the Con Edison underground transmission system.
The T Plant facilities in the 200-West Area of the Hanford site were constructed in the early 1940s to produce nuclear materials in support of national defense activities. T Plant includes the 271-T facility, the 221-T facility, and several support facilities (eg, 2706-T), utilities, and tanks/piping systems. T Plant has been recommended as the primary interim decontamination facility for the Hanford site. Project W-259 will provide capital upgrades to the T Plant facilities to comply with Federal and State of Washington environmental regulations for secondary containment and leakdetection. This document provides an advanced conceptual design concept that complies with functional requirements for the T Plant Secondary Containment and LeakDetection upgrades.
Eight years ago, corrosion and tube denting seriously threatened the reliability and design life of steam generators, especially for closed loop arrangements in pressurized water reactors (PWRs). Concentrated research by the Steam Generator Owners Group (SGOG) diagnosed the causes and produced effective solutions, notably guidelines for water chemistry control in the secondary loop. The guidelines recommend specific levels of water impurities and remedial actions to prevent cooling-waterleaks in the condenser, prevent air leaks, limit corrosion product buildup, and remove some impurities while neutralizing others. Continued research in SGOB-II is investigating intergranular corrosion and stress corrosion cracking. 3 figures.
Eight years ago, corrosion and tube denting seriously threatened the reliability and design life of steam generators, especially for closed loop arrangements in pressurized water reactors (PWRs). Concentrated research by the Steam Generator Owners Group (SGOG) diagnosed the causes and produced effective solutions, notably guidelines for water chemistry control in the secondary loop. The guidelines recommend specific levels of water impurities and remedial actions to prevent cooling-waterleaks in the condenser, prevent air leaks, limit corrosion product buildup, and remove some impurities while neutralizing others. Continued research in SGOB-II is investigating intergranular corrosion and stress corrosion cracking. 3 figures.
Pipeline leakdetection technologies can be classified according to their specificity, such as their application to offshore or onshore installations or to multi-phase or single-phase flow regimes. They can also be classified according to the technology on which they are based. Available technologies can be categorized into the following 4 groups: (1) compensated mass balance, solving steady state equations which model a specific pipeline, known as real time mode (RTM), (2) the same as group 1, but solving transient equations, known as real time transient model (RTTM), (3) pressure wave behavior, and (4) statistical modeling. Hybrids schemes can also be found. Effective leakdetection systems are needed to address the increasing transformation of very large crude cargo (VLCC) ships into floating production, storage and offloading (FPSO) systems. These operations make use of short and large diameters ...
A scheme is presented for the generation of entangled states for two cavity mirrors. In the scheme each mirror initially in a vacuum state interacts with a weak coherent field, resulting in a photon-number dependent kick. The detection of a photon leaking from the cavities collapses the two mirrors to an entangled state.
Leak-before-break (LBB) analyses for circumferentially cracked pipes are currently being conducted in the nuclear industry to justify elimination of pipe whip restraints and jet impingement shields which are present because of the expected dynamic effects from pipe rupture. The application of the LBB methodology frequently requires calculation of leak rates. These leak rates depend on the crack-opening area of a through-wall crack in the pipe. In addition to LBB analyses, which assume a hypothetical flaw size, there is also interest in the integrity of actual leaking cracks corresponding to current leakage detection requirements in NRC Regulatory Guide 1.45, or for assessing temporary repair of Class 2 and 3 pipes that have leaks as are being evaluated in ASME Section 11. This study was requested by the NRC to review, evaluate, and refine current analytical ...
During the summer of 2003, a gastroenteritis outbreak spread throughout a holiday resort in central Italy. Fecally contaminated groundwater and seawater were leaking into the non–drinking-water...Full Text Available
The development and successful application of a unique leak sealant formulation comprised of a mixture of graded, hollow ceramic microspheres, surface oxidized aluminum powder and saturated gibbsite suspension is described. The project was undertaken to address the escalating leakage from up to 15 small weld defects in the water reflector vessel, an integral component of the NRU (National Research Universal) reactor calandria. The reflector surrounds the reactor core with a neutron reflecting blanket of light water. Injection of the sealant is typically done with the reactor shutdown and the water reflector system operating normally, but can also be performed with the reactor at full power. The procedure is simple and effective. Individual treatments of as little as 125 ml of sealant (10 ppm in the 12,500 L system) have yielded leak reductions exceeding 2000 L/day. The accumulated ...
Encapsulation of a unique isotopic blend of krypton and xenon gas employs a special application of laser technology. The encapsulated gas is then used as the primary medium for detection and identification of failed nuclear fuel rods. The use of gas tagging as a means of detecting and identifying failed nuclear fuel rods has been successfully demonstrated and used by the Argonne National Laboratory, Experimental Breeder Reactor (EBR-2) Project, and the Westinghouse Hanford Company (WHC), Fast Flux Test Facility (FFTF) Fast Breeder Reactor Program. The Power Reactor and Nuclear Fuel Development Corporation (PNC) of Japan has selected this leakdetection system for use in their MONJU Prototype Reactor fuel assemblies. The MONJU reactor is almost identical in design to the highly successful FFTF reactor, which is currently in standby status.
The loss of seal of the H9 channel in vacuum, freeing the entire cross section of the front part, leads to a fast leak that progresses rapidly. The effect of depressurizing the reflector can leads to shutdown of the shutdown rod pumps. The source changer associated with the channel fills completely before the valve closes. All of the leakwater remains contained within the source changer containment. After the valves open, cooling of the fuel element is handled by natural convection, requiring a reversal of the flow between the plates. This changeover, which takes place at a relatively low pressure level, could lead to local boiling in the fuel element. Consequently, irreversible transformations cannot be excluded as possibilities for the fuel element and even for the control rod. Subsequently, the can is refilled with heavy water with establishment of the usual pressure levels.
A significant amount of X-rays were detected as a leakage from some of the Crooke`s tubes which were used in the teaching of science at junior and senior high schools in Japan. We measured the leaked dose of X-rays from the Crooke`s tubes with ionizing chambers, film badges and TLDs. The maximum leaked dose at 5cm distance from those tubes was estimated 143mSv/h. The effective energy of leaked X-rays was 19.3keV. The maximum dose of students exposed during the teaching of science were estimated 0.15mSv per experiment, which exceeded the value recommended in the ICRP publication 36. (author)
It is imperative to use a leak-proof container for counting liquid sample to prevent contamination of costly gamma detectors. A sealant that ensures no leak is reported. It is a vinyl adhesive sealant used for household purposes, marketed by Gloucester Co., Inc, Franklin, MA under the trade name of Phenoseal (translucent variety). This sealant was superior to other sealants studied because it cures quickly, peels off easily after counting, and contains no detectable radioactivity. This sealant has been thoroughly tested and successfully employed it in the routine analysis of environmental liquid samples. (author)
This paper presents the experience faced by people who works in PETROBRAS Business Unit (UN-RNCE), located in Rio Grande do Norte Province, Brazil, during the implementation of a pipeline leakdetection system. That application involved nine multiphase oil pipelines distributed along several production facilities. Because of the emergency after the leakage that polluted the Guanabara bay and due to the two phases and multi phases pipelines characteristics, the UN-RNCE decided to apply the Pressure Point Analysis (PPA) technology in order to detect leakages. It is a statistical method for leakdetection e uses a very simple instrumentation which facilitates the installation and maintenance. However, in order to get the best performance of the system, it is necessary to know thoroughly the whole process and have a fast and reliable SCADA system for long distance communication. Finally ...
Recently, the leak-before-break (LBB) concept has been used successfully to eliminate some pipe whip restraints, snubbers and jet impingement shields from the primary reactor cooling system piping of pressurized water reactors. This has resulted in substantial savings in maintenance costs, reductions in radiation exposure of plant service personnel, and has enhanced the overall safety of nuclear power plants. This study provides guidelines to utilities in expanding the application of the LBB concept to additional pipe systems and it couples the concept with hardware optimization. Seven high energy piping systems were investigated for technical feasibility in using the LBB concept. The results indicate that some of these seven lines are good candidates for the leak-before-break application.
With an objective to detect gas leaking from an underground gas pipeline, discussions have been given on a method which utilizes acoustic characteristics of leakage. On leaking sound generated from damaged portions, the form of damaging was hypothesized as pinholes, and spectra of leaking sounds from holes with different diameters were measured. The dominant frequency decreases as the hole diameter increases, while it is in a region of relatively high frequency of 1 kHz or higher. However, detection from the ground surface was impossible when cover soil has thickness from 0.5 to 1.5 m. In an experiment to measure leaking sound inside the pipe, pressure in the pipe was adjusted to 0.02 atm which is a standard pressure for a low-pressure pipe, and the sound was measured when the hole diameters were varied. In any of the results obtained by varying the hole ...
In allusion to the explosion of a urea reactor took place in a fertilizer plant at Pingyin, Shandong, China, a series of evidence collection and inspection jobs which includes collecting operation condition and parameters, sampling the explosion fracture, reactor body apart from explosion fracture, and leakdetection medium and its hangover, etc., had been carried out firstly. Based on these jobs, farther analysis and computation work has been done to the structural and materials characteristics and the operation condition of the urea reactor, including compositions, metallographic phases, tensile properties, impact energy, strain ageing characteristics, and fracture toughness of the urea reactor steels, the compositions of leakdetection medium and its hangover in the urea reactor, and ex...
Purpose: To permit accurate detection of sodium leakage by distinguishing between variations in the overflow tank level due to changes in sodium temperature accompanying changes in the power level or operating state of a liquid metal sodium cooled fast breeder, and a reduction in power level due to duct leakage. Constitution: The volume of sodium in the primary cooling system is roughly estimated from the temperatures of hot and cold legs, and the duct leak preset level with respect to the sodium liquid level within an overflow tank when the plant is normal is varied according to the state of the plant. More particularly, the volume of sodium within the overflow tank is calculated on the basis of a signal representing the liquid level detected by a liquid level gauge in the overflow tank and a signal representing the temperature detected by hot leg and cold leg thermometers, thereby obtaining the preset ...
This spring, Newfoundland will send off a floating production, storage and offloading (FPSO) vessel to the offshore Terra Nova field. The Terra Nova will proceed southeast through Bull Arm, then northeast out of Trinity Bay, then heads southeast to the Jeanne d'Arc Basin on the Grand Banks. The Terra Nova is expected to produce 115,000 barrels of oil per day for six years, when it reaches full capacity. The consortium, headed by Petro-Canada as senior ownership partner and operator, built an environment protection program into every aspect of the project. Some of the features of the environment protection program include glory holes excavated on the ocean floor for the protection of production equipment from icebergs, to a flare stack on the platform, which has four legs to provide stability in rough seas. The FPSO was designed to withstand sea ice, icebergs, and severe winter storms. Flow lines are also protected, and in the event that a line is damaged, sea ...
Piping systems transporting high-pressure fluid will release a large amount of energy, leading to whipping of the broken pipe as well as impingement of the ejecting fluids on adjacent structures if they fracture unstably. Postulation of such an event in design of piping systems in nuclear power plants often requires various counter measures such as installation of pipe whip restraints or jet impingement shields to prevent such damage. One of the approaches to justify exclusion of unstable fracture from the design conditions is leak-before-break (LBB) analysis. In order to demonstrate LBB behavior, it is necessary to prove that in the presence of a part-through wall flaw in the pipe, this flaw will not grow through the wall under fatigue loading and is stable (level 2 LBB) and that the leak of fluid through the penetration is detected by leakdetection systems before unstable ...
Prepared to make housing project managers, maintenance engineering staff, and designers and architects of HUD - assisted and HUD - insured housing projects and mobile home parks aware of their responsibilities under the Natural Gas Pipeline Safety Act, this handbook provides technical guidance for the reduction of gas leaks and the handling of gas leak incidents in residential areas. The hazards of natural gas, concern over gas safety in residential areas, applicable codes and standards, and sources of information and help are reviewed, along with maintenance and engineering considerations relating to gas pipe failures, the detection of gas leaks, appliance servicing, and pipe installation, repair, and replacement. Housing management considerations are also examined, with attention to recordkeeping and reporting, emergency contingency planning, tenant education, staff qualifications and training, and ...
The leak before break (LBB) concept is difficult to apply to a structure with a thin tube that is immersed in a water environment. A heat exchanger in a nuclear power plant is such a structure. The present paper addresses an application of the LBB concept to a heat exchanger in a nuclear power plant. The minimum leaked coolant amount containing the radioactive material which can activate the radiation detector device installed near the heat exchanger is assumed. The postulated initial flaw size that cannot grow to the critical flaw size within the time period to activate the radiation detector is justified. In this case, the radiation detector can activate the warning signal caused by coolant leakage from initially postulated flaws of the heat exchanger. The nuclear plant can safely shutdown when this occurs. Since the postulated initial flaw size can not grow to the critical flaw size, the structural integrity of the heat ...
On February 1, 1984, the US Nuclear Regulatory Commission issued Generic Letter 84-04 on the subject of postulated pipe breaks in pressurized water reactor (PWR) primary coolant loops, opening the way for pipe-whip restraint exemptions. The letter substitutes the leak-before-break (LBB) criteria for the double-ended guillotine break regarding PWR primary reactor coolant system (RCS) piping and asymmetric blowdown loads. The LBB criterion refers to the fact that a piping flaw will leak before it breaks. The current requirement to provide pipe-whip restraints is applied within the plant to all high-energy piping with a potential for damaging structures, systems, and components essential to safe reactor shutdown. This includes primary RCS piping 30 in. and larger as well as smaller piping systems. A study was performed to evaluate the applicability of the LBB criteria proposed in NUREG-1061 to the latter set. The costs and ...
An independent investigation of pipe welding leaks from the Low-Level Waste 2 (LLW2) Skid-B System for the possibilities of improper welding (IW), microbiologically influenced corrosion (MIC), sensitization, chloride pitting corrosion (CPC), and intergranular stress corrosion cracking (IGSCC) was conducted. The results show the prevailing mechanisms that caused the leaks are identified as IW, CPC, and the improper selection of weld filler material for the base metals in an environment of the North Plateau underground water. These is no evidence of MIC, sensitization, or IGSCC. The chloride pitting corrosion mechanism that took place at all the welds are also described. All the pipelines were replaced with polyvinyl chloride (PVC) for cost saving and the LLW2 Skid B System has been successfully operating since 1999. This report summarizes the findings and recommendations associated with preventive measures for future ...
Problem areas in BWRs, PWRs and PHWRs, from the viewpoint of chemistry, and the problem of fission product release in nuclear reactors are discussed. These problem areas are : fuel performance, off-normal water chemistry due to condenser leaks, the transport and deposition of the activated corrosion and fission products, denting in steam generators (in the case of PWRs), ingress of air in the cover gas helium and consequent radiolysis of D_2O in the moderator circuit (in the case of PHWRs). (M.G.B.).
... Deepwater Horizon leak in the Gulf of Mexico, the Haitian earthquake and subsequent response, release of information by WikiLeaks, the Icelandic ...
Although the Federal Facility Agreement (FFA) addresses the entire Oak Ridge Reservation, specific requirements are set forth for the liquid low-level radioactive waste (LLLW) storage tanks and their associated piping and equipment, tank systems, at ORNL. The stated objected of the FFA as it relates to these tank systems is to ensure that structural integrity, containment and detection of releases, and source control are maintained pending final remedial action at the site. The FFA requires that leaking LLLW tank systems be immediately removed from service. It also requires the LLLW tank systems that do not meet the design and performance requirements established for secondary containment and leakdetection be either upgraded or replaced. The FFA establishes a procedural framework for implementing the environmental laws. For the LLLW tank systems, this framework requires the specified plans and ...
The defects localization in power cables follows several steps: identification, pre-localization and precise localization. Pre-localization methods, other than echo-metry, are presented first: bridge methods, particular case of low voltage networks, future perspectives. Then, the precise localization methods are described: magneto-acoustic method, audible frequencies method. The particular case of underwater and high-voltage cables is considered too (oil and gas leaksdetection). (J.S.)
The Japan Atomic Energy Research Institute has conducted a piping reliability test program to demonstrate the safety and reliability of light water reactor primary piping. In this program, pipe fatigue test, leak-before-break (LBB) verification test and pipe rupture test were carried out to examine the integrity of piping, to verify the LBB and to demonstrate the effectiveness of protective measures against jet impingement and pipe whip loads under a pipe rupture event.In the pipe fatigue test, a procedure to predict the fatigue crack growth was developed, and the integrity of piping during the plant service life was evaluated. In the LBB verification test, the pipe fracture test and the leak rate test were performed to verify the LBB in the primary piping.In the pipe rupture test, the influence of jet impingement on the target disk and the deformation behavior of whipping pipe and restraint were investigated. Using the ...
Upon request by the Science and Technology Agency of Japanese Government, the Japan Atomic Energy Research Institute has conducted Piping Reliability Test Program to demonstrate the safety and reliability of light water reactor primary pipings. In this report, the results of the program are summarized. In the test program, pipe fatigue tests, Leak-Before-Break (LBB) verification tests and pipe rupture tests were carried out to examine the integrity of pipings, to verify the LBB concept and to demonstrate the effectiveness of the protective measures against jet impingement and pipe whip under pipe rupture event, respectively. In the pipe fatigue tests, a procedure to predict the fatigue crack growth was developed and the integrity of piping during plant service life was demonstrated. In the LBB verification tests, pipe fracture tests and leak rate tests were performed using cracked pipes. Based on the test results, LBB in ...
A study has been conducted on the statistics of detected neutrons that leaked from four subcritical reflected, enriched-uranium assemblies, to explore the feasibility of developing a criticality warning system based on neutron noise analysis. Studies were conducted on three possible discriminators, i.e., three signatures that might be used to discriminate among assemblies of various multiplications. The noise analysis techniques studied performed well enough in deeply subcritical situations to deserve testing in an applications environment. They have a good chance of detecting changes in reactivity that are potentially dangerous. One can expect sharpest results when doing comparisons, i.e., when comparing two records, one taken in the past under circumstances known to be normal and one taken now to search for change.
After a brief review of the degradations occurring on tubes of Inconel 600 in steam generators of PWR power stations emphasis is put on the conditioning of the secondary water and more particularly on the condensate treatment in the units of Doel which work on heavily polluted brackish water. The important role of non-destructive testing and eddy-current testing is also pointed out, method developed by Laborelec. The operational experience shows that Belgian stations are nearly not concerned by the degradations mostly found in power stations in other countries which shows the efficiency of the conditioning of the secondary water. On the other hand, other problems have occurred, resulting from: damage caused by foreign objects; fouling of tube before commissioning, cracking of bends and at the limit of the dudgeoning and leaking plugs. (AF).
Cesium recovery from the polluted layers in the 1/3 scale hydrogen negative ion source for LHD-NBI system has tested. It was found, that the cesium recovery can be produced by additional discharges as from the cesium layer, aged by tungsten and residual gas, so as from the cesium layers, polluted by an occasional waterleak. The highest cesium recovery to NI production was produced by a xenon arc, while glow discharge and arcing in hydrogen were less effective. The mechanism of recovery is the ejection of cesium from the underlying enriched layer by the arc and its transport to the surface. (author)
In the safety assessment of a potential repository for spent nuclear fuel, it is important to assess the consequences of a hypothetical leak of radionuclides through the seabed and into a waterborne transport phase. Radionuclides adsorbed to sediment particles may be transported great distances through the processes of sedimentation and resuspension. This study investigates the transport patterns of sediment particles of two different sizes, released in the Forsmark and Laxemar area. The results show that the closed waters around Forsmark to a higher degree makes the particles stay in the area close to the release points
Characterization and performance testing of a prototype DWPF Melter No.2 Dome Heater Bus Bar are described. The prototype bus bar was designed to address the design features of the existing system which may have contributed to waterleaks on Melter No.1. Performance testing of the prototype revealed significant improvement over the existing design in reduction of both bus bar and heater connection maximum temperature, while characterization revealed a few minor design and manufacturing flaws in the bar. The prototype is recommended as an improvement over the existing design. Recommendations are also made in the area of quality control to ensure that critical design requirements are met.
Hepatobiliary scintigraphy is the only non-invasive technique providing real-time assessment of hepatocytes function and bile progression from the liver to the intestine; for this reason it is of great importance in the study of jaundice and many other disorders of the liver and the biliary tract in children. Ultrasonography is the initial method of evaluating the intra- and extrahepatic bile ducts dilatation: the differential diagnosis between biliary atresia and neonatal hepatitis cannot however be done without hepatobiliary scintigraphy. Cystic fibrosis patients also require hepatobiliary scintigraphy; liver and biliary tract disease can really occur independently of the underlying disease severity and the presence of steatorrhoea. Hepatobiliary imaging in children who have undergone liver transplantation is of major importance; it can assess vascularity, parenchymal function biliary drainage, possible presence of a bile leak and obstruction; it has very good ...
The leakage behavior of containments beyond design conditions and knowledge of failure modes is required for evaluation of mitigation strategies for severe accidents, risk studies, emergency preparedness planning, and siting. These studies are directed towards assessing the risk and consequences of severe accidents. An accident sequence analysis conducted on a Boiling Water Reactor (BWR), Mark I (MK I), indicated very high temperatures in the dry-well region, which is the location of the majority of electrical penetration assemblies. Because of the high temperatures, it was postulated in the ORNL study that the sealants would fail and all the electrical penetration assemblies would leak before structural failure would occur. Since other containments had similar electrical penetration assemblies, it was concluded that all containments would experience the same type of failure. The results of this study, however, show that this conclusion does ...
The solar central receiver at the Barstow Pilot Plant is a once-through steam boiler consisting of vertical arrays of Alloy 800 tubes. Water/steam leaks associated with tube bends near the receiver outlet were observed after 16 service months. The leaks resulted from through-wall cracks localized in the crown of tube bends operating in the temperature range from 550 to 650/sup 0/C. Initiation occurred on the ID (steam side) of the tube and propagated transgranular through the tube wall. Cracking was axial and circumferential; in general, the circumferential cracks were more severe than the axial cracks. Thick oxide layers showed on the ID of the receiver tubes; a 25-..mu..m thick oxide layer had formed on tubing which operated at 650/sup 0/C. In addition, an enhanced oxidation layer was observed along a narrow band in the crown of the tube. This band was up to five times thicker than the oxide elsewhere in the tube. All ...
Implementation of Noble Metal Chemical Application (NMCA) in a Boiling Water Reactor (BWR) requires injection of a noble metal compound while the reactor is idle at hot shutdown conditions. In order to minimize outage time, utilities are very pro-actively finding ways to reduce the number of critical path tasks. One of these tasks is to remove some containment vessel drywell head bolts during the NMCA idle time. This, thereby, saves the utilities outage time, or they can perform other tasks as desired. Using design basis conditions and state-of-the-art analytical techniques, detailed finite element stress analyses of the closure region are performed. Two acceptance criteria are evaluated. The first is that contained within Section III of the ASME Code for allowable stresses. The second relates to leak tightness, i.e., with bolt removal the joint must still remain leak tight. This paper describes the activities performed to ...
ambassador in Mexico, Carlos Pascual, does he still have your confidence after the WikiLeaks scandals? (In Spanish.) SECRETARY CLINTON: Well, I deeply regret the WikiLeaks...
Object: To limit the discharge amount of reactor water in a primary system at the time of scram to prevent excessive outflow of reactor water outside the system. Structure: A signal from an upper limit position indicator detects the fact that control rods are completely inserted when the reactor is urgently stopped and the detection signal causes a valve in an outflow line of the discharge water from a control rod driving mechanism to be closed to limit the amount of discharge flown into the scram discharge vessel, thus preventing outflow of reactor water in the primary system after the scram has been initiated. (Kamimura, M.).
The paper-insulated low-pressure oil-filled cable invented in 1917 has been used throughout the world as the major cable system for voltages from 33kV to 525kV and experimentally to 1100kV. The proven reliability of the design is amply demonstrated by the cables installed in the early 1930s still currently in service. The inherent design of an oil-filled cable requires that the low viscosity oil is retained within a lead or aluminium sheath. Changes in oil volume due to changes in ambient temperature and load are accommodated by oil reservoirs which maintain the cable oil pressure within design limits. A microprocessor monitoring system that allows early detection and quick location of oil leaks from high voltage oil-filled cables is described.
analysis of NaMBT in ethylene glycol-water solutions with high accuracy. It reduces analysis time, requires smaller samples, and is able to detect extremely ...
Solid-phase extraction and gas chromatography with electron-capture detection has been used for sensitive, simple, and reliable analysis of carfentrazone-ethyl residues in water. Carfentrazone-ethyl was enriched by use of multiwalled carbon nanotubes (MWCNT), a new adsorptive material. Several conditions affecting recovery of the analyte, for example polarity and volume of eluents, pH of water samples, and sample volume, were studied. Recovery from fortified samples, linear range, and limit of detection were evaluated. The results showed that MWCNT are an efficient SPE adsorbent for preconcentration of carfentrazone-ethyl in water. Under the optimized SPE conditions, recovery of carfentrazone-ethyl from fortified water was 81.49?91.08%, with RSD from 1.66 to 8.21%. The limits of detection ...
Among the numerous free-living amoebae (FLA) of soil and water habitats, certain species belonging to two genera Acanthamoeba and Naegleria are facultative parasites of man.They cause disease called primary amoebic meningoencephalitis where history of contact with water was recorded in most of the cases especially with Naegleria species. The present work aimed to search for presence of free-living amoebae in the water and trials for its control by Ultraviolet-radiation (UV-radiation). Samples from different water sources were examined for the presence of free-living amoebae. These samples were cultured on non-nutrient agar streaked with bacteria. Amoebae were detected and identified by means of their morphological characters. Twelve positive cases of one hundred and twenty examined samples could be detected. The positive samples were exposed to different doses ...
Integrated Leakage Rate Test (ILRT) of containment system plays a very important role in safety of a Nuclear Power Plant. Containment system constitutes the last physical barrier to release of radioactivity from the core and is called upon to mitigate the consequences of not only accidents within the design basis, but also some of the highly unlikely severe accidents. Hence, leak tightness of containment becomes uttermost priority for the safety of plant personnel and public. The containment and associated ESFs are tested before the first criticality and there after periodically during service. The pre-operational integrated leakage rate is carried out at LOCA based design pressure, at periodic test pressure and at some intermediate pressure points to assess the leakage characteristics. This paper summarizes the various requirements and activities relevant to the ILRT of the Indian Pressurized Heavy Water Reactor (PHWR) containment system. ...
The Fast Flux Test Facility (FFTF) is a liquid-metal-cooled, fast neutron test reactor located on the Hanford Site. A dual computer system has been developed to monitor the reactor cover gas to detect and characterize any fuel or test pin fission gas releases. The system acquires gamma spectra data, identifies isotopes, calculates specific isotope and overall cover gas activity, presents control room alarms and displays, and records and prints data and analysis reports. The Fission Gas Monitor System (FGMS) integrates commercially available hardware and software, providing a reliable and easily maintained system. The design provides extensive automation of previous manual operations, reducing the need for operator training and minimizing the potential for operator error. The dual nature of the system allows either system A or B to be taken out of service for periodic tests or maintenance without interrupting the overall system performance. A control room color ...
Ophir Corporation was awarded a contract by the U. S. Department of Energy, National Energy Technology Laboratory under the Project Title ''Airborne, Optical Remote Sensing of Methane and Ethane for Natural Gas Pipeline LeakDetection'' on October 14, 2002. This second six-month technical report summarizes the progress made towards defining, designing, and developing the hardware and software segments of the airborne, optical remote methane and ethane sensor. The most challenging task to date has been to identify a vendor capable of designing and developing a light source with the appropriate output wavelength and power. This report will document the work that has been done to identify design requirements, and potential vendors for the light source. Significant progress has also been made in characterizing the amount of light return available from a remote target at various distances from the light source. A ...
Most palladium thin film based hydrogen gas sensors have response and recovery times that are too long to make them useful in vehicular and stationary gas leakdetection applications. In contrast, a palladium-silver thin film based microcantilever (MC) hydrogen gas microsensor is reported herein with near ideal response characteristics for use in these hydrogen economy related applications. Specifically, 3-10 second response and recovery times have been measured for these sensors in contrast to previous sensor response measurements of several to tens of minutes using Pd thin film and MC based sensing techniques. The much reduced response times observed in the present study are attributed to a wet chemical Pd-Ag thin film deposition technique and a gas conditioning protocol that produces a highly nanostructured, porous film that rapidly adsorbs and desorbs H2, allowing rapid equilibration with the H2 concentration in the surrounding air. The wet ...
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 largest outbreak of cryptosporidiosis reported in the United Kingdom, involving 575 confirmed cases (of which 474 met an agreed case definition), occurred in the county of Devon during August and September of 1995. The descriptive epidemiology supports the hypothesis that the outbreak was associated with the consumption of cold tap water in the area served by a particular water treatment works. Cryptosporidium oocysts were detected in treated water samples at the time of the outbreak. Although the epidemiological analysis provided strong circumstantial evidence of a waterborne outbreak, the data were not recorded in a manner that made them admissible in criminal proceedings taken by the Drinking Water Inspectorate against the water company involved. The need to carry out an analytical study in conjunction with the identification and characterisation of the ...
The 1993 Petroleum Hydrocarbons Conference was comprised of 3 days of technical presentations within the following topic areas: pollution prevention and cost control; development of remediation levels; free-phase and dissolved hydrocarbon contamination management; investigation and analysis of petroleum hydrocarbons; applications of computer modeling for remediation; design and implementation of bioventing; design and implementation of air sparging; soil vapor extraction as a remediation technique; and ground water remediation using natural bacteria. In addition, more than 100 leading companies in the ground water and petroleum industries participated in the Conference Exposition in which a variety of equipment and services for preventing, detecting and remediating ground water contaminated by petroleum hydrocarbons and other organic chemicals was showcased. Individual papers have been processed ...
In General Electric's design of the Simplified Boiling Water Reactor (SBWR), The depressurization valves (DPV) are installed in the reactor pressure boundary: four are connected to the reactor vessel by means of nozzles, and two more are located on the main steam pipes (one DPV for each line), which act during particular transients and/or loss of coolant accidents (LOCA), consequently providing the reactor vessel with a safe quick depressurization system. Once the vessel is de pressurised, the passive gravity-driven cooling system (GDCS) starts to operate, permitting the injection of water required for continuous core cooling. DPVs are leak tight, with welded flaps, actuated by a [striker[hammer***] which is activated by an explosive mixture. The dynamic loads that open these valves include, in addition to those produced by steam (typical in any thermodynamic transient with open/close valves), other important loads that are ...
Before the implementation Water Framework directive, it was usual to forget that a good environment protection of the receiving waters needs a correct and coordinated operation of the subsystems of the water cycle, specially sewerage system, WWTP and receiving waters. This explains that most of the countries have focused their efforts in the treatment of dry weather flows forgetting the management of wet weather flows. Actually the idea that a sewerage system or a WWTP can not be planned or managed independently without considering the effects on the receiving waters is commonly accepted because not only each one of these systems must work correctly but also it is required a minimum impact in the receiving waters of the sewerage and WWTP overflows in dry and wet weather. All these links will affect the management strategy of the sewerage system (storm ...
region, and we think that's a win-win for all of us. MODERATOR: I want to talk about WikiLeaks. Do you think that WikiLeaks has contributed to the decline of American influence in...
Apr 25, 2010... oil per day were leaking from an oil well in the Gulf of Mexico in late April, following an explosion at an offshore drilling rig on April 20, 2010. ...
... sensitive and classified US Government information, a notable recent example being the unlawful release of classified US documents by WikiLeaks ...
The approach estimating the leak probability of flanged joint due to the destruction of fastening studs is described. The mentioned approach consists of two stages. The probability of destroying one stud is calculated at the first stage, and the probability of different combination interpositions of intact and destroyed studs is calculated at the second one. The probability calculation of leak in the area of collector cover of steam generator PGV-1000 is used as an example of developed approach
Radionuclide techniques have commonly been used to assess ventriculovenous shunt function, cerebrospinal fluid dynamics, and for the diagnosis of cerebrospinal fluid leaks. All of these techniques were utilized in this unusual case of retrograde migration of a ventriculoatrial catheter into the neck, with cutaneous fistulization and CSF leak. (orig.).
A new method of pinpointing dielectric fluid leaks on pipe-type and self-contained cables using perfluorocarbon tracer (PFT) is presented. The method has successfully been used on the Con Edison transmission system to locate leaks of dielectric fluid on both types of cables. Application of the PFT technique does not require feeder deenergization and provides major advantages over the conventional method of freeze and pressure testing. Description of the method and results of field application are presented in the paper.
The Nuclear Safety Commission acknowledged the policy of the Agency of Natural Resources and Energy to cope with these important matters on August 8, 1984. The main contents of the investigation and deliberation were as follows, As to the prevention of the occurrence of fires, the prevention of the leak and spread of inflammable liquid and gas, the installation of protective relays and so on, the use of incombustible materials and aseismatic design and the installation of lightning arresters. As to the detection of fires and fire fighting, the proper selection and arrangement of fire detectors and extinguishers, the extinguishers which do not harm the safety function of structures and equipment, and the extinguishers which are not affected by natural phenomena. As to the reduction of the effect of fires, the proper installation of fire walls and extinguishers, and the high temperature shut off of nuclear reactors which is never hampered by any ...
Drums is an acronym for Dynamic Rating and Underground Monitoring System, with specific application to high-pressure pipe-type cable systems which are the predominant means of underground electric power transmission in the United States. The primary objective of this EPRI-sponsored feasibility study was to establish the technical feasibility of seven DRUMS functions and two novel DRUMS communication schemes. The seven DRUMS functions which monitor the system's vital and measurable parameters in real time and perform system diagnostics in the event of component deterioration, malfunction or failure are: Real Time Current Monitoring and Rating; LeakDetection and Location; Fault Location; Pothead Monitoring; Oil Monitoring; Pipe Protection; and Splice Monitoring. The two DRUMS communication schemes are internal to the pipe cable system. Mechanical Communication will use pressure pulses to transmit data along the system, while the ...
Throughout the DOE complex there are numerous facilities that handle hazardous and radioactive waste solutions. Due to the hazardous constituents of the mixed waste, secondary containment of tank systems and their ancillary piping, in accordance with Resource Conservation and Recovery Act, is a concern for such existing facilities. The Idaho Division of Environmental Quality was petitioned in 1990 for an Equivalent Device determination regarding secondary containment of waste lines embedded in interior concrete walls. The petition was granted; however, it expires in 1996. To address the secondary containment issue, additional studies were undertaken. One study verified the hypothesis that an interior wall pipe leak would follow the path of least resistance through the naturally occurring void found below a rigidly supported pipe and pass into an adjacent room where detection could occur, before any significant deterioration of the concrete ...
A new type of ionization chamber with levitated electrode has been developed. In this ionization chamber, an ion-collection electrode levitates in the air without getting any physical support from the insulator. The electrode is charged by an electrostatic charger without physical contact. The charge of the electrode is read out at a Faraday cage periodically at a given time interval without physical contact. Because its electrode levitates, the ionization chamber produces no background current caused by leaks or piezo current. In addition, as the charging of its electrode and the read-out of its charge are carried out without physical contact, no irregular charge or contact potential difference due to the chattering between electrode and contact point occurs. Through experiments, it was found that this ionization chamber was able to measure the {gamma}-ray dose such as the environmental radiation with a high degree of sensitivity. The minimum ...
With the fire accident in Browns Ferry nuclear power plant as a turning point, the regulation against fire has been strengthened more strictly as seen in the regulatory guide of the United States Nuclear Regulatory Commission. Fire of cables is caused by either the ignition of a cable itself or spread of fire to cables. The aspect of fire is divided into the local ignition and combution and the fire extension and prepagation because of the line-shaped configuration of cables. This report describes the prevention of the spread of fire. As the materials for the prevention of fire spread, fire spread-preventing paint ''Dannekka'', sealant ''Danseal P and L'', and fire prevention tape ''FD tape'' are reported, and the testing method and the results are described in detail. ''Dannekka'' is classified into the solvent dispersion type and the water dispersion type. It may be coated with brush or by spraying. Seal material is required not only to be flame preventive but ...
Bobbin-coil-type eddy current probes, which are conventionally used for nondestructive inspection of steam generator tubes in pressurized-water-type nuclear power plants, have poor detectability for circumferential flaws. Hence a new type of eddy current probe was proposed to detect effectively the magnetic flux component disturbed by a flaw and thus to eliminate the flaw direction dependency on the flaw detectability. In the course of development of the proposed method, structures of the probe were investigated based on the measurement of magnetic fields induced by exciting flat coils with several shapes. The new type of probe proposed here consists of differential pick-up coils detecting magnetic flux and exciting coils having a parallelogrammic shape, and its structure was fabricated experimentally in order to detect flaws independently of their directions. ...
Xylem failure via gas embolism (cavitation) induced by water stress was investigated in the palm Rhapis excelsa (Thumb.) Henry. Xylem embolism in excised stems and petioles was detected...Full Text Available
A two-step polymerase chain reaction (PCR) procedure with two nested pairs of primers specific for the yadA gene of Yersinia enterocolitica was developed. The PCR assay identified all common pathogenic...Full Text Available
A microemulsion comprised of water, Brij 78, pentanol and styrene into which PPO and bis-MSB had been dissolved was prepared. Polymerization of the styrene resulted in a suspension of fluor-containing polystyrene nanoparticles (<100 nm). After a concentration step, the aqueous nanosuspension was able to detect {sup 14}C with counting efficiencies over 50% of those of a commercially available scintillation cocktail. Monte Carlo calculations demonstrated that the size and concentration of the nanoparticles were appropriate for optimum detection efficiency.
Conventional eddy current bobbin probes are known to be ineffectual in detecting circumferential cracks in tubing. Multi-pancake and/or rotating pancake probes are required to detect circumferential cracks. It has recently been demonstrated in CANDU steam generator tubes, with deformation, ferromagnetic deposits, and copper deposits, that multi-channel probes with transmit-receive (T/R) coils are superior to those using surface impedance coils. Unlike rotating probes, the design of a new probe denoted as C3 permits fast, single-scan inspection of a full-length tube at inspection speeds comparable to conventional bobbin probes. Since 1992, the probe has been used routinely for steam generator in-service inspection at 4 CANDU plants. Defective tubes have been plugged and the units returned to service, and they continue to operate without leaks. This paper describes the basic features of T/R surface probes. Two-dimensional ...
Conventional eddy current bobbin probes are known to be ineffectual in detecting circumferential cracks in tubing. Multi-pancake and/or rotating pancake probes are required to detect circumferential cracks. It has recently been demonstrated in CANDU steam generator tubes, with deformation, ferromagnetic deposits, and copper deposits, that multi-channel probes with transmit-receive (T/R) coils are superior to those using surface impedance coils. Unlike rotating probes, the design of a new probe denoted as C3 permits fast, single-scan inspection of a full-length tube at inspection speeds comparable to conventional bobbin probes. Since 1992, the probe has been used routinely for steam generator in-service inspection at 4 CANDU plants. Defective tubes have been plugged and the units returned to service, and they continue to operate without leaks. This paper describes the basic features of T/R surface probes. Two-dimensional ...
The US DOE manages the safe storage of approximately 650,000 tons of depleted uranium hexafluoride remaining from the Cold War. This slightly radioactive, but chemically active, material is contained in more than 46,000 steel storage cylinders that are located at Oak Ridge, Tennessee; Paducah, Kentucky; and Portsmouth, Ohio. Some of the cylinders are more than 40 years old, and approximately 17,500 are considered problem cylinders because their physical integrity is questionable. These cylinders require an annual visual inspection. The remainder of the 46,000-plus cylinders must be visually inspected every four years. Currently, the cylinder inspection program is extremely labor intensive. Because these inspections are accomplished visually, they may not be effective in the early detection of leaking cylinders. The inspection program requires approximately 12--14 full-time-equivalent (FTE) employees. At the cost of approximately $125K per FTE, ...
Since the mid-1990s, nuclear power plants in Korea have experienced wall thinning, leaks, and ruptures of secondary side piping caused by flow-accelerated corrosion (FAC). The pipe failures have increased as operating time progresses. In order to prevent the FAC-induced pipe failures and to develop an effective FAC management strategy, KEPRI and KOPEC have conducted a study for developing systematic FAC management technology for secondary side piping of all Korean nuclear power plants. As a part of the study, FAC analyses were performed using the CHECWORKS code. The analysis results were used to select components for inspection and to determine inspection intervals on each nuclear power plant. This paper describes the introduction of the FAC analysis method and the wall thinning trend analysis results by reactor type, system, and water treatment amine. This paper also represents the site application feasibility for secondary side piping ...
The authors present arguments against nuclear energy and pro renewable energy sources. Thus, the water used in Uranium mining and primary ore processing becomes contaminated in long lived radioisotopes and so a threat for local ecosystems and communities. Then, during the fabrication, enrichment, and handling of nuclear fuel the workers are exposed to radiations and dangerous accidental radioactive leaks can occur. But, by far, the most menacing aspect of nuclear power exploitation remains the human errors in operating the nuclear plants which can result in major accidents like that from Chernobyl which spread radioactivity all over the Europe. The equipment used in nuclear facilities which is highly contaminated as well as the burned fuel implies transportation and long term storage which also present high risks. The major advantage of the nuclear energy consists in its very low environment impact and its null contribution to the greenhouse ...
RELAP5 (Reactor Excursion and Leak Analysis Program) is a system code developed at the Idaho National Environmental and Engineering Laboratory for thermal hydraulic analysis of nuclear reactors. The code RELAP5 is widely used for safety analysis studies of commercial nuclear power plants. However, recent released version of RELAP5/3.2 and over present significant capabilities for analysis of nuclear reactor research systems. As a contribution to the assessment of RELAP5/3.3 for research reactor safety analysis, experimental data from the University of Massachusetts Lowell Research Reactor UMLRR are used. The UMLRR is a 1 MW, light water moderated and cooled, graphite-reflected, open-pool type research reactor. This paper presents the development and the validation of a UMLRR-RELAP model using experimental data. For this purpose, a series of experiments were performed for benchmarking RELAP5 calculations for research reactor systems. As a result ...
Several types of corrosion have damaged alloy 600 tubing in the secondary side of steam generators. The types of corrosion include wastage, denting, intergranular attack, stress corrosion, erosion-corrosion, etc. The environments which cause attack may originate from leaks of cooling water into the condensate, etc. When the contaminated feedwater is pumped into the generator, the impurities may concentrate first 200 to 400 fold in the bulk water, depending on the blowdown, and then further to saturation and dryness in heated tube support plate crevices. Characterization of local solution chemistries is the first step to predict and correct the type of corrosion that can occur. The pH is of particular importance because it is a major factor governing the rate of corrosion reactions. The pH of a solution at high temperature is not the same as the ambient temperature, since ionic dissociation constants, solubility and ...
Benchmark calculations for SCALE4.4 CSAS6 module have been performed for 31 UO{sub 2} fuel, 15MOX fuel and 10 metal material criticality experiments and then calculation biases of the SCALE 4.4 CSAS6 module have been revealed to be 0.00982, 0.00579 and 0.02347, respectively. When CSAS6 is applied to the criticality safety analysis for the mockup facility in which several kinds of nuclear material components are included, the calculation bias of CSAS6 is conservatively taken to be 0.02347. With the aid of this benchmarked code system, criticality safety analyses for the mockup facility at normal and hypothetical accidental conditions have been carried out. It appears that the maximum K{sub eff} is 0.28356 well below than the critical limit, K{sub eff}=0.95 at normal condition. In a hypothetical accidental condition, the maximum K{sub eff} is found to be 0.73527 much lower than the subcritical limit. For another hypothetical accidental condition the nuclear material ...
Spectrophotometric method, using a ratio-recording ultraviolet-absorption spectrophotometer, permits analysis of NaMBT in ethylene glycol-water solutions with high accuracy. It reduces analysis time, requires smaller samples, and is able to detect extremely small concentrations of mercaptobenzothiazole.
This book provides discusses recent developments in oil pollution control instrumentation. Some of the topics covered are as follows: 1. Technical requirements of the IMCO International Performance and Test Specification A393x concerning oil content meters; and 2. Oil in waterdetection; and 3. Methods for the disposal of recovered oil and oily sludge; and 4. Oil content monitoring at ballast water treatment facilities and offshore production platforms.
A method based on the collection of [sup 99]Tc from 500 l sea water samples by anion exchange and further extraction of TcO[sub 4][sup -] into 5% triisooctylamine-xylene has been improved to include a decontamination factor 6.5x10[sup 5] for uranium. The detection limit for [sup 99]Tc is thereby reduced to 3 mBq/m[sup 3].
Nuclear energy provides a third of Europe's electricity with nearly no greenhouse-gas emissions. Sustained efforts are now being conducted to harmonize regulations all over Europe through WENRA and to converge on technical nuclear safety practices within the TSO network ETSON (European Technical Safety Organizations Network). In CANDU type NPP the tritiated water occurs by the neutron bombardment of deuterium. The tritiated water vapors imply health hazard (in the critical organs of the body the water presents a 10 day average biological half-life) and the early detection in nuclear plants of tritium emissions is important because the tritiated water vapors have the same characteristics as of atmospheric water vapors. By detecting tritiated vapors, the monitoring system ensures the following objectives: (a) indicates levels of tritium ...
Liquid Zone Control (LZC) System is a 'first-of-its-kind' reactivity control device, designed and implemented at TAPP-3 and 4. The system provides zonal and bulk power control. The system consists of fourteen Zone Control Compartments (ZCCs) containing demineralised light water as neutron absorber. Reactivity control is achieved by varying the level of water in the compartments bi-directionally. Six in-core zircaloy assemblies, housing the fourteen ZCCs and an elaborate process system constitute the LZC system. Measurement of water levels in the ZCCs is done using helium bubbler method. Reliability of ZCC water level measurement is of paramount importance. Commissioning and operating the new system trouble free was a challenge, considering the complex nature of the system. While commissioning the system, level measurement of one of the ZCCs (ZCC - 1) was found erratic and inconsistent. Methodologies ...
A water trap system based on a thermoelectric cooling device is employed to remove a major fraction of the water from air samples, prior to analysis of these samples for chemical composition, by a variety of analytical techniques where water vapor interferes with the measurement process. These analytical techniques include infrared spectroscopy, mass spectrometry, ion mobility spectrometry and gas chromatography. The thermoelectric system for trapping water present in air samples can substantially improve detection sensitivity in these analytical techniques when it is necessary to measure trace analytes with concentrations in the ppm (parts per million) or ppb (parts per billion) partial pressure range. The thermoelectric trap design is compact and amenable to use in a portable gas monitoring instrumentation.
Real-time neutron radiography was demonstrated to be a viable and useful tool in studying water flow in unsaturated media. The experiment was designed to test the method for following water flow. The wetting front advance, water-flow patterns, and neutron attenuation density were observed in a 7.7-cm diameter sand column. The advance was fit with a simple i = A t/sup B/ equation yielding an excellent correlation. Theoretical calculations presented estimate the minimum and maximum detectablewater content in various sizes of columns. The ability of real-time neutron radiography to allow both qualitative and quantitative spatial and time measurements to be made in an nonintrusive manner was demonstrated.
Real-time neutron radiography was demonstrated to be a viable and useful tool in studying water flow in unsaturated media. The experiment was designed to test the method for following water flow. The wetting front advance, water-flow patterns, and neutron attenuation density were observed in a 7.7-cm diameter sand column. The advance was fit with a simple i = A t/sup B/ equation yielding an excellent correlation. Theoretical calculations presented estimate the minimum and maximum detectablewater content in various sizes of columns. The ability of real-time neutron radiography to allow both qualitative and quantitative spatial and time measurements to be made in an nonintrusive manner was demonstrated.
Many mines and processing facilities are in remote, difficult to access areas, or are in areas where access is limited or restricted for national reasons. In a joint project with Canada Centre for Remote Sensing, the Canadian Safeguards Support Program is investigating utility of multi- and hyperspectral remote sensing for remotely inspecting such site. With a view to eventually using the hyperspectral satellite data now coming available, airborne data over uranium and copper mine tailings and uranium processing facilities in northern Canada were acquired. The objective of this work is to demonstrate that multispectral and hyperspectral data can provide complementary and supplementary information to high-resolution panchromatic imagery for the following safeguards applications: Inspection aids (up-to-date maps of remote locations), change detection, evaluation of member state declarations, monitoring of reactor, mining and processing facility operations, and ...
The proposed portable device is suitable for radon surveys in water-bearing strata. It allows a complete transfer in activated charcoal canisters of radon dissolved in water collected with a 0.61 bottle. The detection is performed in laboratory with a low background {gamma}-ray spectrometer utilizing 3{sup x}3{sup N}aI({tau}I) scintillator only after about ten hours. This time is necessary to let radon be uniformly distributed within the activated charcoal.
The bibliography contains citations concerning the pitting corrosion of copper and copper alloys, in different media, with some references to methods for protecting against such corrosion. Included are factors contributing to the onset of pitting corrosion. Emphasis is placed on exposure to water, especially in tubing for heat exchangers and water conduits. Many of the citations present studies on exposure to sea water. Some references pertain to the detection of pitting corrosion in installations and the evaluation of the degree of pitting present. (Contains 250 citations and includes a subject term index and title list.)
ObjectivesObjectives Not AvailableDescriptionTo determine the effects of water penetration on the burst strength of filament wound composite pipes which have been damaged by impact and then subjected to long term pressurisation with sea water. ~%~ To monitor and characterise the damage and effects of sea water penetration using ultrasonic NDT. To determine the burst strength of bonded composite pipe joints with and without defects and to see whether the defects can be detected using ultrasonic NDT. [continued...
For location of leakage at district heating pipelines several techniques are available today. If there is no wire bound lead monitoring system installed, the DH company has to apply mobile methods for detection and location and if possible characterization of leakage. Most mobile methods available today are restricted in application and often they cause supply disconnections, especially the location of very small leaks is difficult. The Institute for Environmental, Safety and Energy Technology (UMSICHT) has tested a new developed method that can be executed by own employees of DH companies that can be realised parallel to normal supply mode, and that is able to locate and characterize even very small leakages. (orig.) [Deutsch] Zur Lecksuche an Fernwaermeleitungen stehen verschiedene Techniken zur Verfuegung. Wurde beim Bau der Fernwaermetrasse kein drahtgebundenes Ueberwachungssystem eingebaut, ist der Netzbetreiber auf mobile Lecksuchmethoden ...
This invention concerns a hydraulic braking system for loads subjected to impacts and vibrations. These double acting telescopic type hydraulic braking systems possess significant drawbacks linked to possibly important hydraulic leaks due to (a) the use of many dynamic seals in such appliances and (b) the effects of the environment of the system on these seals, particularly when employed in nuclear power stations where the seals reach significant temperatures and are subjected to radiation. Under this invention a remedy is suggested to such drawbacks by integrating means to offset automatically the leaks and the accumulation of hydraulic fluid expansions, as well as facilities to show if such leaks have occurred.
that needs to change is the ambiguity in the laws themselves. QUESTION: The issue of WikiLeaks raised? DEPUTY ASSISTANT SECRETARY BAER: It was not. It was raised by the students....
Vacuum pressure standards of the orifice-flow type require known gas flows of 10/sup -6/ mol/s (10/sup -2/ atm cm/sup 3//s at 0 /sup 0/C) and less. Known gas flows can also be used to calibrate ''standard'' leaks by comparing the pressures generated when flows from the leak and the flowmeter are alternately passed through a constant conductance. Two constant-pressure, piston displacement flowmeters developed at the National Bureau of Standards are described that can generate flows between 10/sup -6/ and 10/sup -10/ mol/s with an estimated uncertainty of 0.8% to 2%. Comparisons of the flowmeters with alternate calibration techniques, and repeated low-range leak and vacuum gauge calibrations, have been used to confirm the estimated uncertainty and random errors of the flowmeter.
Sources of industrial emissions of 1,3-butadiene are discussed both by process (production, consumers) and type (equipment leaks, point sources). Quantification of the emissions are presented, as reported...Full Text Available
for cyber issues? Did you decide to establish this position because of the WikiLeaks incident? DR. SLAUGHTER: No. No, that decision was actually taken nearly a year ago,...
site for reference information. Other recipients include Google's Translator, WikiLeaks, The ICUN Red List of Threatened Species, and the Public Library of Science (PLOS)....
AIM:The study compares the efficiency, side effects and complications of autologous blood pleurodesis with talcum powder and tetracycline.MATERIALS...Full Text Available
A simple enantioselective HPLC method was developed for measuring carfentrazone-ethyl enantiomers. The separation and determination was accomplished on an amylose tris[(S)-a-methylbenzylcarbamate] (Chiralpak AS) column using n-hexane/ethanol (98:2, v/v) as mobile phase at a flow rate of 1.0 mL/min with UV detection at 248 nm. The effects of mobile-phase composition and column temperature on the enantioseparation were discussed. The accuracy, precision, linearity, LODs, and LOQ of the method were also investigated. LOD was 0.001 mg/kg in water, 0.015 mg/kg in soil and wheat, with an LOQ of 0.0025 mg/kg in water and 0.05 mg/kg in soil and wheat for each enantiomer of carfentrazone-ethyl. SPE was used for the enrichment and cleanup of soil, water, and wheat samples. Recoveries for two enantio...
In this work, a water-soluble polymer, polyethylenimine (PEI) was used for the simultaneous separation and preconcentration of trace Cu and Mn prior to their determination by flame atomic absorption spectrometry. For this purpose, the sample and the PEI solution were mixed and the metal-bound polymer was precipitated by adding acetone. The precipitate was separated and dissolved in a minimum amounts of water and aspirated into a flame AAS. By increasing the ratio of the volumes of sample to water used in dissolving the precipitate, the analyte elements were concentrated as needed. The sorption is quantitative in the pH ?6. Detection limits were 5.2 ?g/L for Cu and 5.4 ?g/L for Mn. This method is simple, fast and precise.
Effect of water injection/draining on elastic waves penetrating through cracks is examined by measuring elastic waves before, during, and after the injection/draining of water into/from cracks in presence in granite. Two blocks of rock, with their crack-containing surfaces in contact with each other, are placed in a vessel, and water injection/draining is done through a hole on a vessel bottom side so that water will penetrate into the cracks. When the blocks are dry, there is almost no contact between the cracks, and so no crack penetrating waves are observed. Crack penetrating waves are produced when water is injected, and the position of the receiver sensing the penetrating waves changes as the water level rises. When the water level is lowered from the high water level, the waveform changes again as the level ...
In the quest to understand the ultimate nature of WIMPs, we propose the use of a hybrid detection technique: cylinders filled with liquefied noble gasses, acting as targets, are immersed inside a tank of Gd-doped ultra-pure water that provides an active and efficient veto against neutrons. The evaluation of the background rejection capabilities and physics potential of this instrument have been carried out through a full GEANT4 simulation, assuming the detector will be located at the Canfranc underground laboratory (in the Spanish Pyrenees). Our results compare very favourably with existing or planned experiments in the field. This technique is scalable and will allow to reach target masses of few tonnes in the next future.
Soil gas, soil, and water were assessed for organic and inorganic constituents at the former 19th Street landfill at Fort Gordon, Georgia, from February to September 2010. Passive soil-gas samplers were analyzed to evaluate organic constituents in the hyporheic zone and flood plain of a creek and soil gas within the estimated boundaries of the former landfill. Soil and water samples were analyzed to evaluate inorganic constituents in soil samples, and organic and inorganic constituents in the surface water of a creek adjacent to the landfill, respectively. This assessment was conducted to provide environmental constituent data to Fort Gordon pursuant to requirements of the Resource Conservation and Recovery Act Part B Hazardous Waste Permit process. The passive soil-gas samplers deployed in the water-saturated hyporheic zone and flood plain of the creek adjacent to the former landfill indicated the ...
This study highlights a methodology to detect the transplanting operation of wetland rice at a regional scale using SSM/I brightness temperature in frequencies like 19, 37 and 85 GHz with vertical polarization. A cloud removal algorithm was used to make weekly composites of the brightness temperature, which were used to estimate the soil wetness index (SWI). Flooding of rice fields with water for transplanting induces very high change in SWI due to contrasting dielectric constant of water (80) and soil (4). Different weather conditions and fractional wet area under the footprint of sensor affect SWI, hence absolute value of SWI was not adequate. Therefore, multi-year SWI anomaly was used to generate a threshold value of SWI change to detect when SWI change between two consecutive weeks was...
Among pharmaceuticals and personal care products released into the aquatic environment, antibiotics are of particular concern, because of their ubiquity and health effects. Although scientists have recently paid more attention to the threat of antibiotics to coastal ecosystems, researchers have often focused on relatively few antibiotics, because of the absence of suitable analytical methods. We have therefore developed a method for the rapid detection of 36 antibiotic residues in coastal waters, including tetracyclines (TCs), sulfanilamides (SAs), and quinolones (QLs). The method consists of solid-phase extraction (SPE) and liquid chromatography-tandem mass spectrometry (LC-MS/MS) analysis, using electrospray ionization (ESI) in positive mode. The SPE was performed with Oasis HLB and Oasi...
About ten years ago microbiologically influenced corrosion manifested on stainless steel pipes used with river water for cooling a chemical plant. The pipe material was similar to Type 316 L. After only six weeks of operation pinhole leaks occurred nearly simultaneously at several welded joints of the pipe. The material degradation was simulated in laboratory and field corrosion tests. Microbiologically influenced corrosion failures also appeared on the pipes of a tubular heat exchanger of duplex steel Type 31803 and on carbon and stainless steel pipes in industrial waste water purification plants after these plants had been modernized with a biological purification unit. The basics of microbiologically influenced corrosion phenomena and typical corrosion failures of pipes will be described. (orig.) [German] Vor etwa zehn Jahren sind in einer neu errichteten chemischen Produktionsanlage an einer mit Flusswasser ...
A cryocondensation pump was designed for the baffle chamber of General Atomics DIII-D tokamak and will be installed in the fall of 1992. The purpose of the pump is to study plasma density control by pumping the divertor. The pump is toroidally continuous, approximately 10 m long and located in the lower outer corner of the vacuum chamber of the machine. It consists of a 1 m{sup 2} liquid helium-cooled surface surrounded by a liquid nitrogen-cooled shield to limit the heat load on the helium-cooled surface. The liquid nitrogen-cooled surface is surrounded by a radiation/particle shield to prevent energetic particles from impacting and releasing condensed water molecules. A thermal enhancement coating was applied to the nitrogen shell to lower the maximum temperature of the shell. The coating is non-continuous to keep the toroidal electrical resistance high. The whole pump is supported off the water-cooled vacuum vessel wall. Supports for the ...
Conditions of the separation and detection of organic and inorganic anions by gradient ion chromatography and suppressed conductivity detection were studied, and the procedure of gradient elution was optimized. A detection limit of 1 x 10{sup -3} {mu}g x L{sup -1} was obtained using the pre-concentrated column and most relative standard deviations obtained in the determination of seven organic and inorganic anions were below 5%. This method was proved to be simple, rapid and accurate for the separation and determination of low-molecular-weight organic acids and inorganic anions and could be applied in the analysis of the samples from water and steam systems of thermal power plants with satisfactory results. (orig.)
A controlled field pilot has been developed in Bozeman, Montana, USA, to study near surface CO2 transport and detection technologies. A slotted horizontal well divided into six zones was installed in the shallow subsurface. The scale and CO2 release rates were chosen to be relevant to developing monitoring strategies for geological carbon storage. The field site was characterized before injection, and CO2 transport and concentrations in saturated soil and the vadose zone were modeled. Controlled releases of CO2 from the horizontal well were performed in the summers of 2007 and 2008, and collaborators from six national labs, three universities, and the U.S. Geological Survey investigated movement of CO2 through the soil, water, plants, and air with a wide range of near surface detection techniques. An overview of these results will be presented.
The activated charcoal treatment in the field of the water treatment is applied to water supply, sewage, industrial water supply and industrial sewage, etc.. Its main treatment effects are (1) decolorization, (2) removal of odorous substance, (3) removal of organic material which is detected as COD or BOD, (4) removal of harmful substance, (5) removal of substance which could generate muddness and tarnish and (6) removal of organic material which affects the succeeding high degree treatment badly, etc.. Many actual application examples in the above fields have been reported. As the most recent topic, a big amount of the demand of activated charcoal is expected in the treatment of water supply. Chlorine which is used as disinfectant during the water purification process generates organic halogen compounds such as trihalomethane through the reaction with precursor ...
Many thermoluminescent materials has been developed and used for photon personal dosimetry but no one has all desired characteristics alone. These characteristics include robustness, high sensitivity, energy photon independence, large range of photon energy detection, good reproducibility, small fading and simple glow curve with peaks above 150 deg C. Calcium Sulfate Dysprosium doped (CaSO{sub 4}:Dy) phosphor Thermoluminescent Dosimeter (TLD) has been used by many laboratories, mainly in Brazil and India. Another interesting phosphor is Calcium Fluoride (CaF{sub 2}). These phosphor advantages begin to be more required and its disadvantages have became more apparent, in a global market more and more competitive. These phosphors are used in environmental and area monitoring, once they present more sensibility than other phosphors, like LiF:Mg. Theirs mainly disadvantage is a strong energetic dependence response, which must be corrected for theirs application in the ...
Many electric power utilities are currently employing machine condition monitoring technologies as a means of reducing forced outages and controlling repair costs. These condition monitoring technologies are a set of {open_quotes}tools{close_quotes} to help maintenance and operations personnel identify and repair machinery problems before catastrophic failure occurs. In this way, the analysis of this data becomes a vital link in the daily operation of the plant. Machinery vibration analysis, machinery balancing and alignment, motor current testing, periodic thermography surveys, analysis of lubrication oil samples, performance monitoring, chemistry monitoring, ultrasonic leakdetection surveys, and non-destructive inspections are some of the technologies available to perform this condition monitoring. However, even for a small or medium size plant, the sheer volume of data provided by applying all or some of these technologies can be ...
Historical information about the F-Area Railroad Crosstie Pile is limited. The unit is believed to have been a borrow area for earth fill that began receiving railroad crossties during the 1960s. The number of crossties at the unit began to increase significantly in 1984 when major repair of the SRS rail system was initiated. An estimated 100,000 used railroad crossties have accumulated at the unit since 1984. In an effort to determine the impact of the railroad crossties on the environment a total of 28 soil samples were collected from four test borings in March of 1991. Sample depths ranged from ground surface to 21.5 feet. Three of the borings were extended to the water table and groundwater samples were collected, one in an upgradient ``background`` area, and two downgradient from the unit. Few analytes were reported above detection limits. Test results are summarized in Section 4.0 and analytes not detected are ...
Historical information about the F-Area Railroad Crosstie Pile is limited. The unit is believed to have been a borrow area for earth fill that began receiving railroad crossties during the 1960s. The number of crossties at the unit began to increase significantly in 1984 when major repair of the SRS rail system was initiated. An estimated 100,000 used railroad crossties have accumulated at the unit since 1984. In an effort to determine the impact of the railroad crossties on the environment a total of 28 soil samples were collected from four test borings in March of 1991. Sample depths ranged from ground surface to 21.5 feet. Three of the borings were extended to the water table and groundwater samples were collected, one in an upgradient background'' area, and two downgradient from the unit. Few analytes were reported above detection limits. Test results are summarized in Section 4.0 and analytes not ...
The optimum conditions of complex formation of rhenium(IV) with acetylacetone in water-ethanol medium were found, and a spectrophotometric method for determining rhenium with limit of detection 0.1 ..mu..g/ml was proposed. Rhenium can be determined in the presence of a 1000-fold excess of molybdenum. The procedure was tested on model solutions and used for the determination of rhenium in alloys.
A rapid and accurate method for the direct simultaneous determination of nitrate and nitrite is proposed. The method is applied to the determination of nitrate and nitrite in rainwater and wastewater without preliminary separation. The determinations are performed by a CPA matrix method with ultraviolet spectrophotometric detection. The results obtained are in agreement with those obtained by conventional methods for the determination of nitrate and nitrite.
Radon concentration measurement in the ground can be used for the prospecting for uranium and earthquake prediction. Some results of radon concentration measurement in the soil are presented here. The moisture condensation at the detector surface can affect on the detection efficiency. Due to this problem we tested a few filter papers on water permeability. The ratio of track densities on solid state nuclear track detector (SSNTD) in the open and the closed diffusion chamber is also determined. (author)
Brief summaries are given of research carried out in the following areas: absorption spectroscopy of titanium, niobium, and molybdenum in uranium alloys; atomic absorption spectroscopy of selenium in stainless steel, computer program improvements for spectrophotometer control, and detection of beryllium in stack gases; electrolysis for inactivation of bacteria in cooling-tower water; improved solvent analysis by gas chromatography; sequential radionuclide separation for various sample matrices; progress on an electron microprobe analyzer; and miscellaneous projects.
Purpose: To obtain stabilized operation by preventing over heat in emergency cooling pumps upon accidents of flow regulators. Constitution: A pressure suppression chamber pool and a pressure vessel are communicated to each other with a pipeway and the water in the suppression pool is charged by a charging pump to the pipeway. The pipeway is interposed with an emergency cooling pump so as to feed water in the pipeway to the pressure vessel and a water source and the emergency cooling pumps are connected by way of a closed pipeway. Further, the closed pipeway and the pipeway interposed with the charging pump are communicated to each other by way of a connecting pipeway, to which are interposed an instrument for detecting the increase in the temperature of the emergency cooling pumps due to abnormality in the closed pipe (such as troubles in flow regulators) and outputting control signals and an ...
The aim of the paper is to review the role of interventional radiology in the management of hemodialysis vascular access and complications in renal transplantation. The evaluation of patients with hemodialysis vascular access is complex. It includes the radiology/ultrasound (US) evaluation of the peripheral veins of the upper extremities with venous mapping and the evaluation of the central vein prior to the access placement and radiological detection and treatment of the stenosis and thrombosis in misfunctional dialysis fistulas. Preoperative screening enables the identification of a suitable vessel to create a hemodynamically-sound dialysis fistula. Clinical and radiological detection of the hemodynamically significant stenosis or occlusion demands fistulography and endovascular treatment. Endovascular prophylactic dilatation of stenosis greater than 50% with associated clinical abnormalities such as flow-rate reduction is warranted to ...
A silicon capacitive accelerometer was fabricated to detect subsurface elastic waves by using micromachining technology. Characteristics required for it call for capability of detecting acceleration with amplitudes from 0.1 to 1 gal and flat amplitude characteristics in frequency bands of 10 Hz to several kHz. For the purpose of measuring transition phenomena, linear phase characteristics in the required bands must be guaranteed, cross sensitivity must be small, and resistance to water, pressure and heat is demanded. Sensitivity of the sensor is determined finally by noise level in a detection circuit. The sensor`s minimum detection capability was 40 mgal in the case of the distance between a weight and an electrode being 3 {mu}m. This specification value is a value realizable by the current micromachining technology. Dimensions for the weight and other members were decided with the ...
Rats were exposed to lead (Pb) before or after weaning. For preweaning exposures, nursing dams received 0.2% Pb acetate(1090 ppm Pb) in drinking water. Offspring treated after weaning consumed the same concentration. Tapwater served as the control fluid. Pre-post treatments were distributed among four experimental groups of 10 rats each: tap water-tap water, Pb-tap water, tap water-Pb, Pb-Pb. Operant behavior training began on Postnatal Day 58. Animals performed on a multiple reinforcement schedule of food presentation consisting of fixed-interval, fixed-ratio, and time out components.Statistical analyses of experimental sessions 4 to 11 (Postnatal Days 72 to 79) revealed that postweaning exposure significantly lengthened the median interval (interresponse time) between consecutive responses on both the interval and ratio schedules. Preweaning exposure alone tended to produce a ...
The first Russian reprocessing facility, known as RT-1 (located at PA-Mayak in Ural region) was started on the radiochemical plant base in 1977. Nowadays RT-1 is the sole operating reprocessing plant in Russia. The main features of RT-1 is its broad spectrum of reprocessing spent nuclear fuels (SNF). The following spent fuel types are reprocessed: -) SNF from PWR reactors (WWER-440) and FB reactor (BN-600); -) SNF of transport ship reactors; -) production reactors SNF; -) research reactor spent nuclear fuel. The world-known technological processes are used at RT-1, but there are the following distinctive features. First, the universality of the three technological lines which allows not only the reprocessing of various SNF kinds, but also to implement the combined reprocessing of some types of them. Secondly, extraction of neptunium during SNF reprocessing which is used to implement its separate storage and for radioisotope production. Thirdly, target enrichment of recycled uranium is ...
The first Russian reprocessing facility, known as RT-1 (located at PA-Mayak in Ural region) was started on the radiochemical plant base in 1977. Nowadays RT-1 is the sole operating reprocessing plant in Russia. The main features of RT-1 is its broad spectrum of reprocessing spent nuclear fuels (SNF). The following spent fuel types are reprocessed: -) SNF from PWR reactors (WWER-440) and FB reactor (BN-600); -) SNF of transport ship reactors; -) production reactors SNF; -) research reactor spent nuclear fuel. The world-known technological processes are used at RT-1, but there are the following distinctive features. First, the universality of the three technological lines which allows not only the reprocessing of various SNF kinds, but also to implement the combined reprocessing of some types of them. Secondly, extraction of neptunium during SNF reprocessing which is used to implement its separate storage and for radioisotope production. Thirdly, target enrichment of recycled uranium is ...
A compact cesium deposition system was used for direct deposition of cesium atoms and ions onto the inner surface of the 1/3 scale Hydrogen Negative Ion Source for the LHD-NBI system. A small, well defined amount of cesium deposition in the range of 3-200 mg was tested. Negative ion extraction and acceleration were carried out both in the pure hydrogen operation mode and in the cesium mode. Single Cs deposition of 3-30 mg to the plasma chamber have produced temporary 2-5 times increases of H-yield, but the yield was decreased within several discharge pulses to the previous steady-state value. Two consecutive 30 mg depositions done within a 3-5 hours/60 shot interval, produced a similar temporary increase of H-beam, but reached a larger H-yield steady-state value. Deposition of larger 0.1-0.2 g Cs portions with a 20-120 hours/150-270 shot interval improved the H-yield for a long (2-5 days) period of operation. Directed depositions of Cs to the various walls of the plasma chamber showed ...
The secondary side corrosion of steam generator tubes is the main degradation of components in operating power plants, strongly impacted by chemistry. This is why EDF has largely studied the chemical parameters in its 56 PWRs which might influence corrosion development. The results of 168 hideout returns of chemical species performed on the French plants allowed to draw conclusions on where chemical species are likely to concentrate in steam generators and on the influence of several contaminants on corrosion processes: sodium, chloride, phosphate, organic compounds, etc... Based on laboratory studies and plants feedback, new chemistry specifications were established and are now applied to EDF units to minimize corrosion and operating costs and to provide a good availability while maintaining an excellent safety. Boric acid is added in the secondary water of the 10 oldest units with Inconel 600 MA tubing, highly sensitive to intergranular stress corrosion cracking. ...
Since 1984 the thermal-hydraulic code ATHLET has been also applied for the analyses of LOCA and transients in VVER plants. The specific design of these plants especially of the steam generator design requires a specific modelling of the phenomena which may occur under LOCA and transient conditions in these plants. Differences in design compared to the design of western reactors have been briefly listed. Specific phenomena occurring under small leak accidents are shortly described. The consideration of the simulation of the boiler-condenser mode illustrates the modelling requirements for a code which may be applied to the prediction of such a thermal-hydraulic behaviour. Facing the lack of experimental data, the reliability of the simulation has been discussed by means of plausibility studies based on the momentum balance for steam and water. In summary: The VVER reactors differ in design compared to reactors of western design. The VVER design, ...
Presented in this report are the quantitative and qualitative aspects of the more than 5,800 applications of Grafoil on-plant. The subject all-graphite product was originally made by the Union Carbide Corporation. Its utilization in the forms of valve packing, gasketing and sealant tapes for leak repair and prevention on-plant since March 1970 is marked with typical zero-leak results. For all practical purposes, the successful results with Grafoil implementation indicate an unqualified control of leakage problems that began in 1967 with the V-11 and V-12 valves in the primary system of N Reactor. Meaningfully, the accruals of savings with existing and future applications shall continue to be incalculable in personnel exposure, maintenance, and capital. Inherent in the savings are the devised methodology and innovative developments coordinately employed in resolving the leak repair problems.
Leakage after oesophageal anastomosis or perforation remains a challenge for the surgeon. Traditional management has been operative repair or intensive conservative management. Both treatments are...Full Text Available
especially since your attack several years ago. I was wondering, in the wake of WikiLeaks, what the Estonians can help the U.S. with in terms of developing an - as...
QUESTION: You've already had one trip where you went to deal with fallout from WikiLeaks. You are visiting a couple of places where the leaders were quoted saying some very...
IntroductionPersistent lymphatic drainage following retroperitoneal lymph node dissection for testicular tumor is an uncommon complication.Case presentationWe...Full Text Available
As the IC Information Sharing Executive (IC ISE), my main focus today concerns classified information--and, in particular, information that is derived from intelligence sources and methods, or information that is reflected in the analytic judgments and as...
efforts to work with other countries to solve shared problems. U.S. Condemns Alleged WikiLeaks Disclosures November 29, 2010: President Obama and Secretary of State Hillary Rodham...
The Fast Flux Test Facility (FFTF) is a liquid-metal-cooled test reactor located on the Hanford Site. The FFTF is the only reactor of this type designed and operated with the intent of meeting the licensing requirements of the Nuclear Regulatory Commission (NRC). Unique characteristics of the FFTF that present special challenges related to leak rate testing include thin wall containment vessel construction, cover gas systems that penetrate containment, and a low-pressure design basis accident. The successful completion in 1986 of the third FFTF Integrated Leak Rate Test (ILRT) five days ahead of schedule and 10% under budget was a major achievement for the Westinghouse Hanford Company. The success of this operational safety test was due in large part to a special local area network (LAN) of three IBM PC/XT computers that monitored the sensor data, calculated the containment vessel leak rate, and displayed test results. The ...
The recent online publication of classified defense documents by the organization WikiLeaks and subsequent reporting by the New York Times and other news media have focused attention on whether such publication violates U.S. criminal law. The Attorney Gen...
The recent online publication of classified defense documents and diplomatic cables by the organization WikiLeaks and subsequent reporting by the New York Times and other news media have focused attention on whether such publication violates U.S. criminal...
AIM: To compare 2 different types of covered esophageal nitinol stents (Ultraflex and Choostent) in terms of efficacy, complications, and long-term outcome.METHODS: A retrospective review of...Full Text Available
Feb 11, 1983 ... Kenmore cooktop stove, three. Saxophone, used only two years,. Executive wood desk, 36" x 72", minutes to NASA, $435/me. plus wagon, ...
A fast and simple flow-through optosensor was designed and characterized for the direct screening of four tetracycline (TCC) antibiotics (tetracycline, oxytetracycline, chlortetracycline and doxycycline) in water and bovine milk samples. The proposed optosensor provides rapid binary yes/no overall responses, being appropriate for the screening of this family of antibiotics above or below a pre-set concentration threshold. The experimental set-up is based on a flow-injection manifold coupled on-line to a phosphorescence detector. Aliquots of the samples are pretreated with Eu(III) to form room temperature phosphorescent metal chelates and injected in the flow manifold. Those chelates are then on-line retained on a conventional flow-cell (packed with polymeric Amberlite XAD-4 particles) which is placed inside the cell holder of the phosphorimeter. After the emission is registered, the antibiotic-metal complexes are eluted from the packed resin with 1 M HCl (for milk ...
This study presents results from Monte Carlo radiation transport calculations aimed at characterizing a novel methodology being developed to detect partial defects in Pressurized Water Reactor (PWR) spent fuel assemblies (SFAs). The methodology uses a combination of measured neutron and gamma fields inside a spent fuel assembly in an in-situ condition where no movement of the fuel assembly is required. Previous studies performed on single isolated assemblies resulted in a unique base signature that would change when some of the fuel in the assembly is replaced with dummy fuel. These studies indicate that this signature is still valid in the in-situ condition enhancing the prospect of building a practical tool, Partial Defect Detector (PDET), which can be used in the field for partial defect detection.
In the present study we quantified the residues of organophosphorus (e.g. ethion and chlorpyrifos), organochlorine (e.g. heptachlor, dicofol, ?-endosulfan, ?-endosulfan, endosulfan sulfate) and synthetic pyrethroid (e.g. cypermethrin and deltamethrin) pesticides in made tea, fresh tea leaves, soils and water bodies from selected tea gardens in the Dooars and Hill regions of West Bengal, India during April and November, 2006. The organophosphorus (OP) pesticide residues were detected in 100% substrate samples of made tea, fresh tea leaves and soil in the Dooars region. In the Hill region, 20% to 40% of the substrate samples contained residues of organophosphorus (OP) pesticides. The organochlorine (OC) pesticide residues were detected in 33% to 100% of the substrate samples, excluding the w...
Abstract Bioluminescent bacteria have been used for many years for biotoxicological analysis. One of the main concerns with this microorganism is the low experimental repeatability when subjected to external factors. The aim of the present study was to obtain accurate, sensitive, and repeatable measurements with stable signals (during the detection and over days) for application in a water-analysis device for the detection of pollutants. Growth conditions were tested and optimized. An optimal freeze-drying procedure for the constitutive bioluminescent bacteria Vibrio fischeri and Photobacterium phosphoreum was developed. The luminescence stability after rehydration was also investigated. Freeze drying was found to be a critical process in survival and signal stability of luminescent bacter...
The results of a study on the application of remote sensing and geophysical methods for the detection and monitoring of acid mine drainage (AMD) are summarized, with emphasis on those that appear most suitable. The study consisted of a literature review, an information survey of users and suppliers, and discussions with various experts. Space-borne sensors, airborne sensors, airborne videography and digital frame cameras, spectroradiometers, radar, and photographic data are considered. Geophysical methods are effective for measurement of sulphides, areas of active chemical oxidation, acid mine drainage, and contaminated ground water movement. The popularity and effectiveness of various geophysical methods are rated for AMD applications. 25 refs., 1 fig., 3 tabs.
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 ...
This paper proposes a self-optimized coverage coordination scheme for two-tier femtocell networks, in which a femtocell base station adjusts the transmit power based on the statistics of the signal and the interference power that is measured at a femtocell downlink. Furthermore, an analytic expression is derived for the coverage leakage probability that a femtocell coverage area leaks into an outdoor macrocell. The coverage analysis is verified by simulation, which shows that the proposed scheme provides sufficient indoor femtocell coverage and that the femtocell coverage does not leak into an outdoor macrocell.
Steam generator tube denting is primarily caused by build-up of corrosion products at the tubesheet and the tube support plates. The mechanism of dent growth and the identification of tubes which should be removed from service have been studied. The practical outcome has been to prevent in-service tube leaks and to avoid unnecessary plugging of large numbers of tubes. A finite element study of tubesheet deformation (of pulled leaking tubes from reactors) was undertaken. Profilometry results for characterizing dents are given. Although several modifications have been made the high resolution profilometry system performance and the results obtained have proved satisfactory. (U.K.).
This report presents the record of the workshop Water Treeing and Aging.'' The workshop was held in Phoenix, Arizona on December 9--11, 1990 and was sponsored by the Distribution Program of the Electrical Systems Division of the Electric Power Research Institute (EPRI). Attendance at the workshop was by invitation only. Twenty two attendees from seven countries, from universities, research organizations, electric utilities and polymeric materials suppliers took part in this workshop. The workshop was designed to assess progress in the understanding of water treeing phenomena and polymeric cable insulation aging since the last meeting of a similar forum of experts, which was organized by the Office of Exploratory Research of EPRI in December 1985. The objective of the present workshop was to assess progress and to provide direction for further studies in this field. The discussions covered a wide range of subjects including ...
Synthetic musks are used in many consumer products for their pleasant odor and their binding affinity for fabrics. In the early 1990s, polycyclic musks were reported to occur in air, water, sediment, wildlife, and humans from many European countries. Concentrations of polycyclic musks, particularly 1,3,4,6,7,8-hexahydro-4,6,6,7,8,8-hexamethyl-cyclopenta-[?]-2-benzopyr an (HHCB) and 7-acetyl-1,1,3,4,4,6-hexamethyl-1,2,3,4-tetrahydronapthalene (AHTN), have been reported to increase over time in the environment. In this study, concentrations of musks in water, sediment, fish, and mussel were determined from three locations along the upper Hudson River. HHCB and AHTN were detected in water (n?=?5; 3.95?25.8 and 5.09?22.8?ng/L, respectively), sediment (n?=?3; 72.8?388 and 113?544?ng/g, dry weig...
Finding environmentally friendly and cost-effective methods to remediate soils contaminated with polycyclic aromatic hydrocarbons (PAHs) is currently a major concern of researchers. In this study, a series of small-scale semi-continuous extractions - with and without in situ wet oxidation - were performed on soils polluted with PAHs, using subcritical water (i.e. liquid water at high temperatures and pressures, but below the critical point) as the removal agent. Experiments were performed in a 300 mL reactor using an aged soil sample. To find the desorption isotherms and oxidation reaction rates, semi-continuous experiments with residence times of 1 and 2 h were performed using aged soil at 250 deg. C and hydrogen peroxide as oxidizing agent. In all combined extraction and oxidation flow experiments, PAHs in the remaining soil after the experiments were almost undetectable. In combined extraction and oxidation no PAHs could be ...
A highly reliable control rod drive mechanism (CRDM) installed inside the reactor vessel has developed for use of an advanced marine reactor. This CRDM contributes to compactness and simplicity of the reactor system, and it can eliminate the possibility of a rod ejection accident. The CRDM works in the high temperature and high pressure water - 310degC and 12 MPa, the same atmosphere as the primary loop. Driving force is produced by a synchronous motor with the rotor of a permanent magnet, which has been developed. An innovative latch mechanism using separable ball nuts can latch driving shaft connecting the control rod and de-latch it for scram. The rod position detector using a magnetostrictive wire type sensor on the principle of Wiedeman effect has been developed, accuracy of which is verified to have a detecting error within 1.2 mm. Ball bearings for thrust and radial supports in rotation have been developed to be capable of working under ...
Previous experiments in fast critical assemblies demonstrated a method of determining reactivity from power spectral density measurements with /sup 252/Cf. This method determines reactivity from properties of the reactor only at the subcritical state of interest, thus it does not require a calibration near delayed criticality. The interpretation of the measured data to obtain reactivity does not require knowledge of the relative or absolute values of the source intensity, knowledge of the detection efficiencies, or knowledge of the detection instrumentation frequency responses. An experiment was performed at the Pool Critical Assembly to evaluate the possibility of /sup 252/Cf source driven neutron noise spectral density measurements in light water moderated reactors. This experiment showed that using commercially available detectors, such measurements can be performed in a reasonable time, that is, the measurement of the ...
Eight different viruses, suspended in drinking water, were examined for their ability to be inactivated by microwaves from a microwave oven. Up to a virus content of 10/sup 5/ TCID/sub 50//ml inactivation was successful within a few minutes of microwave treatment and occurred in parallel to the heat stability of the viruses. Evidence for direct effects of microwaves on viruses could not be detected. 7 of the viruses studied were inactivated rapidly when temperatures of 50 to 65/sup 0/C under microwave treatment were reached in the flowing water, while a bovine parvovirus was only inactivated by temperatures above 90/sup 0/C. The advantages of a thermal virus-decontamination of fluids and material by microwaves are discussed.
This paper summarizes an investigation carried out on Polish terrain occupied by Russian Federation military troops. The investigation identified natural environmental devastation, pollution, and contamination. Quantitative estimation of the devastation and its economic evaluation are provided. The results of the investigation are as follows: 406 ha have been contaminated by petrochemical products; 22.7 ha are chemically polluted; and 6,500 ha of underground water, as well as 17.5 ha of surface water, cannot be classified. On 15,300 ha the soil has been degraded, of which landfills comprise an area of 98 ha. No toxic warfare agents have been detected, nor any radioactivity levels exceeding those characteristic of the given region.
Sales of iodized table salt (household use, bulk containers) have been flat in Germany since 1996/1997. Nevertheless, the amount of iodide excreted with the urine has been steadily increasing in the German population since 1993. We investigated the beverage iodine levels as possible source of the increased input of iodine into the food chain. No systematic studies on this topic have yet been carried out in Germany. A total of 510 samples were drawn from large grocery discounters who supply all German states with their products (35% fruit and vegetable juices, 35% beers, 10% pooled milk and yoghurt drinks, 10% mineral water, 10% soda). (1) Water-based beverage samples are prepared by solid-phase extraction and iodine concentration is determined by HPLC and electrochemical detection, (2) the...
Diffusion magnetic resonance imaging (MRI) has become an important tool in the radiologic diagnosis of diseases of the brain as it measures molecular motion of water that characterizes the microstructure of tissues. Its most important clinical use to date is the early detection of cerebral ischemia by revealing the ischemic injury shortly after vessel occlusion and simultaneously providing therapy-relevant information on the tissue at risk. Furthermore, diffusion MRI is diagnostically promising in other diseases of the brain and is thus increasingly becoming part of routine clinical protocols in the diagnosis of tumors, inflammation, trauma, demyelination, dysmyelination and neurodegeneration. Although abnormalities of diffusion are generally not pathognomonic, diffusion MRI affords information about tissue changes for specific disorders that complements information obtained with standard MR techniques and frequently shows pathology earlier. In ...
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 ...
The sub-criticality monitoring system has been developed for criticality safety control in nuclear fuel handling plants. In the past experiments performed with the Deuterium Critical Assembly (DCA), it was confirmed that the detection of sub-criticality was possible to k{sub eff} = 0.3. To investigate the applicability of the method to more generalized system, experiments were performed in the light-water-moderated system of the modified DCA core. From these experiments, it was confirmed that the prompt decay constant ({alpha}), which was a index of the sub-criticality, was detected between k{sub eff} = 0.623 and k{sub eff} = 0.870 and the difference of 0.05 - 0.1{Delta}k could be distinguished. The {alpha} values were numerically calculated with 2D transport code TWODANT and monte carlo code KENO V.a, and the results were compared with the measured values. The differences between calculated and measured values were proved ...
A sensitive and rapid automated method has been developed for the selective analysis of acid extractable sulfide in environmental samples by combining gas dialysis separation techniques with methylene blue detection procedures. Acid extractable sulfide is separated from the sample matrix by the gas dialysis membrane and subsequently trapped in a dilute sodium hydroxide receiving stream. This stream is reacted with N,N-dimethyl-p-phenylenediamine and ferric chloride to produce methylene blue which is then quantitated colorimetrically at 660 nm. For standards and nonturbid environmental samples, there is good agreement between the results obtained by this procedure and the standard methylene blue method. The effect of interferences on the accurate determination of sulfide by both methods was also examined and it was found that cupric ions significantly interfered with sulfide estimation. To obtain adequate sulfide recoveries in tap water and ...
In this study, a miniature fiber-optic radiation detector has been developed using a water-equivalent organic scintillator for electron beam therapy dosimetry. Usually, two kinds of light signals such as fluorescent and Cherenkov lights are generated in a fiber-optic radiation detector when a high-energy electron beam is irradiated. The fluorescent light signal is produced in the scintillator and is transmitted through a plastic optical fiber to a remote light-measuring device such as a PMT or a photodiode. The Cherenkov light could be also produced in the plastic optical fiber itself and be detected by a light-measuring device. Therefore, it could cause problems or limit the accuracy of the detection of a fluorescent light signal that is proportional to dose. The objectives of this study are to measure, characterize and eliminate Cherenkov light generated in a plastic optical fiber used as a component of a fiber-optic ...
The effect of dissolved oxygen and copper on denting corrosion at 280/sup 0/C in solutions of NaCl at pH 9 with ammonia was investigated using a packed tube/support plate crevice in a laboratory simulation. The onset of corrosion was detected with a hydrogen analyzer sensitive to 0.2 ppB. In the absence of copper, rapidly rising hydrogen concentrations were detected only when the product of the chloride and oxygen concentrations were detected only when the product of the chloride and oxygen concentrations in the boiler-water exceeded 25 (ppM)/sup 2/, but at these high concentrations, unheated low-carbon steel surfaces in the system were as sensitive to corrosion as the heated crevice. When copper metal was present in the feed system, corrosion of the heated crevice occurred in the absence of oxygen, provided the copper had previously been exposed to dissolved oxygen. Dosing hydrazine into the feedwater ...
We report on the detection of SiO and water masers toward a newly found bipolar nebula, IRAS 19312+1950. This object exhibits extreme red IRAS color log (F25/F12)=0.5 and log (F60/F25)=0.7 and a nebulosity having a size of about 30" extended to the South-West in the 2MASS near-infrared image. Toward this object, we have detected emission from the H2O 6(1,6)-5(2,3) transition, the SiO J=1-0, v=1 and 2, and J=2-1, v=1 transitions, and the SO 2(2)--1(1) and H13CN J=1-0 transitions. The thermal lines of SO and H13CN are shifted by about 12 km/s in radial velocity with respect to the maser lines, indicating that thermal emission comes from the background molecular cloud. However, the SiO J=2-1, v=2 spectrum shows another component of SiO emission separated by 26 km/s from the main component, that might be formed in a rotating or expanding shell.
Surveys for interior wetland birds at mine-associated emergent wetlands on coal surface mines in southern Illinois detected one state threatened and two state endangered species. Breeding by least bittern (Ixobrychus exilis) and common moorhen (Gallinula chloropus) was confirmed. Regional assessment of potential wetland bird habitat south of Illinois Interstate 64 identified a total of 8,109 ha of emergent stable water wetlands; 10% were associated with mining. Mine-associated wetlands with persistent hydrology and large expanses of emergent vegetation provide habitat that could potentially compensate for loss of natural wetlands in Illinois.
Apparatus and a method of introducing a primary fuel, which may be a coal water slurry, and a high combustion auxiliary fuel, which may be a conventional diesel oil, into an internal combustion diesel engine comprises detecting the load conditions of the engine, determining the amount of time prior to the top dead center position of the piston to inject the main fuel into the combustion chamber, and determining the relationship of the timing of the injection of the auxiliary fuel into the combustion chamber to achieve a predetermined specific fuel consumption, a predetermined combustion efficiency, and a predetermined peak cylinder firing pressure. 19 figures.
This bibliography contains citations concerning the control and mitigation of radon pollution in homes and commercial buildings. Citations cover radon transport studies in buildings and soils, remedial action proposals on contaminated buildings, soil venting, building ventilation, sealants, filtration systems, water degassing, reduction of radon sources in building materials, and evaluation of existing radon mitigation programs including their cost effectiveness. Analysis and detection of radon and radon toxicity are covered in separate published bibliographies. (Contains 129 citations fully indexed and including a title list.).
Lanthanide-ion doped oxide nanoparticles were functionalized for use as fluorescent biological labels. These nanoparticles are synthesized directly in water which facilitates their functionalization, and are very photostable without emission intermittency. Nanoparticles functionalized with guanidinium groups act as artificial toxins and specifically target sodium channels. They are individually detectable in cardiac myocytes, revealing a heterogeneous distribution of sodium channels. Functionalized oxide nanoparticles appear as a novel tool particularly well adapted to long-term single-molecule tracking.
The transfer of fish from field to laboratory facilities or their propagation in closed or restricted systems frequently results in bacterial infection and ultimately large-scale mortality. In attemps to alleviate this problem, we have added tetracycline hydrochloride to the water prophylactically (pretreating tanks before wild fish were added) and therapeutically (treating tanks after bacterial outbreaks were detected.) In the present study, we examined the effect of tetracyline hydrochloride on the critical thermal maximum (CTM) of the common shiner (Notropis cornutus).
The foils of various materials were irradiated with "6"0Co with an activity of 11,538 TBq. The minimum radiation dose was 25 kGy. Changes in chemico-physical properties were evaluated by infrared spectroscopy and were not detected after irradiation with 25 kGy. Packing foils were subjected to the following tests: mechanical tests, tests of weld strength, tests of impact resistance, free fall tests, permeability tests for water vapour and microbiological tests. The results of all tests were tabulated. The tests showed that the foils are impermeable for microorganisms and provided the welds are airtight the packed products remain sterile. (J.P.).
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 ...
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 ...
Optimum analytical conditions of the aluminium ion were established by flow injection analysis. Eriochrome Cyanine R(ECR) dye reacts with the aluminium ion at pH 6.0 form a complex that exhibits maximum absorption at 535 nm. Reaction condition including the mixing and the reaction coil length, the concentration and the pH of the buffer solution, temperature, and injection loop volume were optimized to introduce this reaction into flow injection analysis. The results were as follows. A mixing coil length of 0.5 m and a reaction coil length of 4.0 m, the pH 6.0 and 1M of acetate buffer solution, the ECR concentration of 0.56 mM, the reaction temperature of 40 .deg. C, the injection loop volume of 300 #mu#L were chosen as optimum conditions. Under these conditions the detection limit of the aluminium ion was less than 0.05 mg/L and the repeatability was better than 1%. A sampling frequency of 24 times for an hour was achieved. Interfering ions such as F"-, HPO_4"2"-, ...
Census and environmental surveillance information on waterfowl that use the Hanford Site 200 Area waste water ponds are described and evaluated. Physical features of the ponds are discussed in relation to their use and suitability for waterfowl. Seasonal distributions observed for the years 1971 through 1974 indicate that the highest use by waterfowl occurs during the spring and fall migratory periods. Base population estimates are 300 to 400 resident waterfowl with a few tens of pairs nesting during the summer. Environmental surveillance data on "1"3"7Cs in muscle tissue are presented for the years 1971 through 1977. Comparisons are made between Columbia River and waste water pond waterfowl, between waterfowl groups, and among ponds. Waterfowl collected from ponds frequently have easily detected levels of "1"3"7Cs in muscle tissue. However, those waterfowl collected from the Columbia River seldom show a "1"3"7Cs level ...
This paper elucidates morphological characteristics, reproduction forms and ecological characteristics of Plectus sp. and Rhabditis sp. which are most frequently detected nematodes separated from tap water. The paper also discussed experimentally establishment of cultivating conditions for these nematodes, and behavior and reproduction characteristics of nematodes under widely ranging conditions of temperatures, bacteria concentrations and pH. Plectus sp. grows in hermaphroditic individuals, while Rhabditis sp. grows only in female. An LE culture medium can cultivate nematodes that appear in tap water, and is suitable for subculture of nematodes. Conditions of temperatures from 20{degree}C to 25{degree}C, pH and inoculated concentration of bacteria at 10{sup 8} cell {center_dot} ml{sup -1} are suitable for reproduction of Plectus sp. and Rhabditis sp. Plectus sp. and Rhabditis sp. prefer mild temperatures for reproduction, ...
In an existent emergency reactor core cooling device, if a ruptures should occure in a pipeline of a gravitational dropping type reactor core cooling system pool (GDCS) due to some or other causes, a portion of GDCS pool water was flown out of the ruptured port and could not be used for reactor core cooling. Then, a difference pressure detector is disposed to a GDCS pipeline at the inlet of a reactor pressure vessel. When it is judged by the detector, that coolants flow to the outside of the injection pipeline, an injection value disposed to the GDCS pipeline is closed by the difference pressure signal. Even if a rupture should occur on the side of the pressure vessel at downstream to the check value of the GDCS pipeline, since backflow is caused at the pressure container inlet of the GDCS pipeline with the rupture port, the rupture is detected by the difference pressure detector to close the injection valve. Therefore, loss of the GDCS pool ...
A rapid extraction procedure has been developed for speciation of arsenic in chicken tissue. Water, methanol-water (1:1), and methanol-chloroform (1:1) were tested as extraction media. Individual use of an ultrasonic bath, a microwave oven, or an ultrasonic probe was not sufficient for quantitative recovery of As(III), dimethylarsinate, monomethylarsonate, As(V), and arsenobetaine in spiked samples of chicken tissue. A new extraction procedure using a methanol-water mixture and a microwave oven then an ultrasonic probe enabled extraction of the arsenic species in 7 min with efficiencies ranging from 80 to 100%. HPLC-UV-HG-AFS was used for the determinations. The extraction procedure was 100% efficient when applied to real samples of chicken tissue. AsB (48{+-}5 {mu}g As kg {sup -1}) and one containing-arsenic feed additive, Nitarsone (227{+-}5 {mu}g As kg {sup -1}) were detected. (orig.)
Extra-fine powdered activated charcoal has been used as stationary phase (coating layer) in solid-phase microextraction (SPME). The efficiency and reliability of the prepared device have been investigated for the extraction of some volatile organic compounds such as benzene, toluene, ethylbenzene and xylene isomers (BTEX) from the headspace of water samples. Monitoring of the extracted compounds and further quantitative analysis of the real samples have been performed by capillary GC-FID. Effects of several factors such as temperature, addition of salt, and stirring speed on extraction efficiency and exposure time have been studied. Under optimum conditions, extraction recoveries for these compounds from 50 mL water were >95%. The calibration graphs were linear in the range 5 to 10{sup 4} pg mL{sup -1} and the detection limit for each BTEX compound was 1.5-2 pg mL{sup -1}. The results obtained by use of this porous layer ...
Possible threats against the leak tightness of the reactor containments, due to pipe whips from hypothetical pipe ruptures in the steam- and feedwater systems, have been investigated for Forsmark 3/Oskarshamn 3, Ringhals 1, Oskarshamn 1 and Barsebaeck 2/Oskarshamn 2. Based on available drawings, such as installation drawings and isometric views of pipes, the pipe systems have been put together in new drawings with their bracing supports and containment walls. This inventory shows that pipe whips can occur on a number of places on the containments walls after hypothetical pipe ruptures in the steam- and main feedwater systems. In order to find out whether these pipe whips are real threats against the leak tightness, further analysis needs to be made but are out of the scope of this investigation.
Methodology based on probabilistic fracture mechanics (PFM) is finding increasing acceptability in demonstrating safety of Nuclear Power Plant (NPP) piping. In PFM, the methods of fracture mechanics and reliability theory are combined for assessing the reliability of components, which contain cracks. In this work, reliability assessment of Tarapur Atomic Power Plant (TAPP) 3-4 Primary Heat Transport (PHT) piping is done using PFM. Monte Carlo simulation with stratified sampling is used as a variance reduction technique. PFM model assumes a pre-existing circumferential surface crack before the start of plant operation. The crack grows in size during the lifetime of the plant due to the fatigue loading. This part-through wall crack having escaped hydro-test and pre-service inspection, may result in either a through wall flaw (leak) or may lead to the rupture of the piping. R6 method is used as failure criteria. Steam generator inlet (SGI), steam generator outlet ...
Studies were conducted to examine the pressure on fluid-filled cables of electric power transmission networks in the event of an oil leak. Transition splices between paper-insulated oil-impregnated cable systems (PILC) and solid dielectric cable is difficult to perform. A proper PILC is composed of a means to contain oil within the cable structure and to keep moisture out. A failure of the cable joint could occur if an oil leak dries out the paper. Since oil pressure in most PILC cables is high, strong mechanical means must be devised to contain the oil within the cable. Resin systems, heat shrink systems and wiped lead sleeves to reseal the PILC cable over the splice, are among the methods used to stop an oil leak. A system has been designed using an EPDM tube contained under mechanical pressure; it has proven to be effective over a wide range of pressure conditions. Test results utilizing this system were presented. 1 ...
Site studies for CANDU type NPP began in a careful manner since 1982 as a first part of the Nuclear Power Plant Romanian Program adopted by political and governmental authorities at the time. A team was charged to develop all packages of the necessary main studies. The first Romanian NPP CANDU 6 type reactor gone to erection on Cernavoda site, planned to have 5 units and, like Wolsong NPP, applied the same design for the nuclear island. For the BOP parts the ANSALDO-GE project was applied with a thorough concern about requirements raised by connection to NSP. The first mission of design and research multi-branch team was to adapt the NPP Cernavoda project having an open water cooling circuit 'once-through' to the new parameters of a close recirculation water cooling circuit. Also, the structural design was re-evaluated for the case of soft foundation strata instead of hard rock ones. The close recirculation water cooling ...
The overall goal of the proposed project is to explore the use of partitioning tracers to characterize dense nonaqueous phase liquids (DNAPLs) in aquifer systems. Bulk-phase partitioning tracers will be investigated to detect and determine DNAPL saturation, while interface partitioning tracers will be investigated to measure the area of the DNAPL-water interface. The specific objectives that will be addressed to accomplish this goal are: (1) Investigate the use of partitioning tracers to detect and determine both the saturation and interfacial area of DNAPLs in saturated porous media. (2) Investigate the effect of rate-limited mass transfer on the transport behavior of partitioning tracers. (3) Investigate the effect of porous-media heterogeneity on the transport behavior of partitioning tracers. (4) Develop and evaluate mathematical models capable of simulating the transport of partitioning tracers in complex systems. This ...
As characterization of artificial cracks formed underground by using the water pressure fracturing method, experiments have been carried out to detect relationship of pressurization and S-wave propagation time with the polarizing direction dependence. Openings are created when pressure in the vicinity of the artificial cracks increases greater than reopening pressure of micro cracks. Elastic wave velocity decreases in this region because of water in the opened micro cracks. Anisotropy is created in the S-wave propagation velocity due to influence from anisotropic reopening region when the artificial cracks are pressurized, and is separated into two components which polarize orthogonally with each other (micro splitting). Field experiments conducted at the Higashi-hachimantai field were analyzed by using wavelet transform. It was possible to detect the S-wave arrival time at high accuracy, and the ...
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Carbon steel is frequently used to construct concentrated sulphuric acid storage tanks. This paper discussed the corrosion performance of carbon steel tanks and outlined the underlying mechanisms responsible for major corrosion modes. Analyses of hydrogen grooving and dilute acid corrosion failure mechanisms were presented. Recent corrosion-induced leak failures were also discussed. The use of anodic protection and organic coatings as a corrosion control measure was also evaluated. The results of laboratory studies that were conducted to understand corrosion-induced failures showed that carbon steel electrodes exhibited transpassive corrosion at relatively high anodic potentials, while stainless steel electrodes exhibited transpassive corrosion at anodic potentials less than 1 V. It was concluded that corrosion-induced leaks can be prevented by using anodic protection and baked phenolic coating technologies. 23 refs., 9 figs.
This patent describes an electrodeless lamp. It comprises: a microwave cavity; a source of microwaves in communication with the cavity; a lamp envelope containing a plasma-forming medium mounted within the microwave cavity; a gas manifold for feeding gas to at least one gas passageway for directing a stream of gas to the outer surface of the envelope; a gas leak passageway leading from the gas manifold; a conductive mesh assembly for retaining microwaves within the cavity and permitting light to be emitted from the cavity. The assembly including gas flow blocking means for preventing the flow of gas through the gas leak passageway when the screen is in place in the lamp; and means for shutting off the source of microwaves when the gas pressure in the manifold drops below a predetermined value.
Studies conducted at the Pacific Northwest National Laboratory (PNNL) in Richland, Washington have focused on developing and evaluating the reliability of nondestructive testing (NDT) approaches for coarse-grained stainless steel reactor components. The objective of this work is to provide information to the United States Nuclear Regulatory Commission (NRC) on the utility, effectiveness and limitation of NDT techniques as related to inservice testing of primary system piping components in pressurized water reactors. We examined cast stainless steel pipe specimens containing thermal and mechanical fatigue cracks located close to the weld roots and having inner and outer diameter surface geometrical conditions that simulate several water reactor primary piping configurations. In addition, segments of vintage centrifugally cast piping were examined to characterize the inherent acoustic noise and scattering caused by grain structures and to ...
Nitrite was measured in atmospheric liquid phase samples between 1998 and 2005 to investigate the heterogeneous formation of nitrous acid in the lower atmosphere, as well as to assess the quality of water recovered from dew. The samples were collected during ground-based cloud field experiments at different German mountain sites (Brocken, Schmucke, and Hohenpeissenberg) and at a site south of the Bordeaux urban area (France). Concentrations found in Bordeaux dew samples (up to 2800 ?gl-1) are comparable to those found elsewhere in urban fog and dew water and considerably higher than those detected in cloud water or rain. Particulate nitrite (and nitrate) as well as HNO2 (HNO3) data in air masses from a foothill site of Mt. Schmucke, before involved in cloud processing, are also presented. In clouds at Mt. Brocken, both the interstitial HNO2 gas and the aqueous phase nitrite concentration have been ...
Current work presents the results of more than 100 measurements of 222Rn activity in drinking water collected at artesian bores at Curitiba region during the period of 2008 - 2009. The measurements were performed at the Laboratory of Applied Nuclear Physics of the Federal University of Technology in cooperation with the Nuclear Technology Development Center (CDTN) of Brazilian Nuclear Energy Committee (CNEN). Experimental setup was based on the Professional Radon Monitor (ALPHA GUARD) connected to specific kit of glass vessels Aqua KIT through the air pump. The equipment was adjusted with air flow of 0.5 L/min. The 222Rn concentration levels were detected and analyzed by the computer every 10 minutes using the software DataEXPERT by GENITRON Instruments. Collected average levels of 222Rn concentration were processed taking into account the volume of water sample and its temperature, atmospheric pressure and the total volume ...
Stabilized austenitic steels can suffer intercrystalline stress corrosion cracking under BWR water conditions. This experience of the last three years, which is important for German nuclear power station technology, has resulted from the discovery of cracks, which were detected in pipework made from titanium-stabilized 1.4541 charged with hot reactor water in six boiling water reactors and in core components made from niobium-stabilized 1.4550 of one BWR plant. Remedies to the pipework have been found by applying optimized materials and fabrication procedures and also by improving water chemistry conditions. (orig.) [Deutsch] Stabilisierte austenitische Staehle koennen unter SWR-Reaktorwasser-Bedingungen interkristalline Spannungsrisskorrosion (IKSpRK) erleiden. Diese fuer die deutsche Kernkraftwerkstechnik bedeutsame Erfahrung der letzten drei Jahre ergab sich aus Rissbefunden, die ...
A procedure for the determination of carboxylic acids (benzoic and C{sub 8}-C{sub 16} aliphatic acids) in oxidised engine oils is described. It is based on a simple and selective derivatisation of the acids with a fluorescent label 9-anthracene-methanol followed by reverse-phase separation on an ODS column with a water-acetonitrile-tetrahydrofuran (20:40:40 by volume) mobile phase and post-column reaction with bis(2,4-dinitrophenyl) oxalate and hydrogen peroxide. The chemiluminiscence emission from the reaction was monitored using a lamina flow-through detector. Analysis of oxidised oils showed that although there was quenching of chemiluminiscence emission by the oil matrix, the acids could be determined over the range 0-0.4% (m/v) in the oil with a detection limit of 0.013% (m/v) (130 pmol on-column with a 20 {mu}l injection) for lauric acid. 8 figs., 2 tabs., 17 refs.
The tidal motion of the ocean water through the ambient magnetic field, generates secondary electric field. This motionally induced electric field can be detected in the sea or inland and has a potential for electrical soundings of the Earth. A first goal of the paper is to gain an understanding of the global distribution of the electric signal due to tidal ocean flow. We simulate the electric signals for two tidal constituents - lunar semidiurnal (M2) and diurnal (O1) tides. We assume a realistic Earth's conductivity model with a surface thin shell and 1-D mantle underneath. Simulations demonstrate that in some coastal regions the amplitudes of the electric field can reach 100 mV/km and 10 mV/km for M2 and O1 tides respectively. The changes of lithosphere resistance produce detectable changes in the tidal electric signals. We show that our predictions are in a good agreement with observations.
An average of 9 million gallons per day of oil-contaminated ballast water off loaded from tankers are treated at the Alyeska Pipeline Service Company Ballast Water Treatment Facility at the terminus of the Trans-Alaska Pipeline in Port Valdez, Alaska. This paper focuses on the results of 2 Prince William Sound Regional Citizens' Advisory Council monitoring programs which detail changes in the chemical composition of treated ballast water as it moves from tankers through the facility and subsequently traces the effluent hydrocarbons into the receiving environment of Port Valdez. The treatment facility involves gravity separation tanks, dissolved air flotation cells and biological treatment tanks. Effluent containing traces of volatile aromatics, including benzene, toluene, ethylbenzene and xylenes, low levels of oil, saturated hydrocarbons and polycyclic aromatic hydrocarbons is being continuously discharged to Port ...
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.
A new on-line monitoring system has been developed for pitting corrosion monitoring of carbon steel tubes in cooling water systems. This monitoring system was found to be quite sensitive to the microbiological activity relating to pitting corrosion on a real-time basis. The value of galvanic current indicates the performance level of pitting corrosion inhibition even in biocide application. In addition, the changes in the galvanic current provide indicative information about the effectiveness in microbiological control program, even when the pressure drop measurement indicates no biofilm formation. It can be also useful in detecting a microbiological control upset. In this paper, an introduction of the new monitoring system as a microbiological control effectiveness monitor and the field test results are discussed.
The population of the hyporheic interstice and moss cushions by meso- and macroinvertebrates as found at the three measuring points along the Alte Riefensbeek and the Grosse Soese, respectively, in the period from March 1987 to May 1988 is studied and evaluated together with chemical measurements performed between 1987 and 1990. The six measuring points are positioned along an acidification gradient ranging from non-acid to severely acidified. Chemical and biological paramerters are studied with regard to their suitability as indicators of acidification. A model is presented which decribes the influence of abiotic anthropogenic and natural factors on invertebrate species diversity and populations and which can serve as a basis for the calculation of critical deposition burdens. (orig.).
In this work, a highly-sensitive polymeric membrane ion selective electrode for determination of tetracycline was constructed by using molecularly imprinted polymer (MIP) particles as quasi-ionophore. The water-compatible MIP particles targeting tetracycline were synthesized with tetracycline as a template molecule, methacrylic acid as a functional monomer, ethylene glycol dimethacrylate as a cross-linker, 2,2?-azobisisobutyronitrile as an initiator and lanthanum ion as a mediator. Benefited from the distinctive performance of the quasi-ionophore and the optimized composition of the membrane and the inner filling solution, the lower detection limit of the electrode was decreased to about 1 ? 10?8 mol/l. It exhibited a good electrode slope 59.8 mV/decade near the theoretical Nernstian one, ...
A headspace gas chromatographic (GC) method, which can be automated, has been developed for determination of methyl bromide. This method has been applied to wheat, flour, cocoa, and peanuts. Samples to be analyzed are placed in headspace sample vials, water is added, and the vials are sealed with Teflon-lined septa. After an appropriate equilibration time at 32 degrees C, the samples are analyzed within 10 h. A sample of the headspace is withdrawn and analyzed on a gas chromatograph equipped with an electron capture detector (ECD). Methyl bromide levels were quantitated by comparison of peak area with a standard. The standard was generated by adding a known amount of methyl bromide to a portion of the matrix being analyzed and which was known to be methyl bromide free. The detection limit of the method was 0.4 ppb. The coefficient of variation (CV) was 6.5% for wheat, 8.3% for flour, 3.3% for cocoa, and 11.6% for peanuts.
This study has confirmed large seasonal and daily variations of Rn in soil gas, developed models for the effects of temperature and moisture on air-water Rn partition, inhibited Rn diffusion from wet soil into sparse large air-filled pores and effects of diffusion into bedrock, demonstrated that organic matter is a major host for 226Ra in soils and that organic-bound Ra largely determines the proportion of 222Rn emanated to pore space, shown that in contrast 220Rn is emanated mainly from 224Ra in Fe-oxides, detected significant disequilibrium between 226Ra and 238U in organic matter and in some recent glacial soils, demonstrated by computer models that air convection driven by temperature differences is expected in moderately permeable soils on hillsides.
This study has confirmed large seasonal and daily variations of Rn in soil gas, developed models for the effects of temperature and moisture on air-water Rn partition, inhibited Rn diffusion from wet soil into sparse large air-filled pores and effects of diffusion into bedrock, demonstrated that organic matter is a major host for 226Ra in soils and that organic-bound Ra largely determines the proportion of 222Rn emanated to pore space, shown that in contrast 220Rn is emanated mainly from 224Ra in Fe-oxides, detected significant disequilibrium between 226Ra and 238U in organic matter and in some recent glacial soils, demonstrated by computer models that air convection driven by temperature differences is expected in moderately permeable soils on hillsides.
Due to shortage of fresh water resources, the vegetation of the eastern region of the United Arab Emirates (UAE) has experienced a series of declines resulting from salinization of groundwater, which is the major source of irrigation. To assess these changes, field measurements combined with Thematic Mapper (TM) and Enhanced Thematic Mapper Plus (ETM+) based Soil Adjusted Vegetation Index (SAVI) were analysed. TM and ETM+ images from two dates, 1987 and 2000 were acquired to enable the computation of the greenness anomalies for three sites in the eastern region, Fujairah, Kalba and Hatta. The results show an overall increase in agricultural area, associated with a severe decrease in vegetation greenness and health conditions, particularly in the Kalba study area. The SAVI values decreased ...
On Oct. 24, 2005, Hurricane Wilma, a category 5 storm, made landfall at Cape Romano, Florida. Three days later, the Center for Robot-Assisted Search and Rescue at the University of South Florida deployed an iSENYS helicopter and a prototype unmanned water surface vehicle, AEOS-1, to survey damage in parts of Marco Island, 14 km from landfall. The effort was the first known use of unmanned sea surface vehicles (USVs) for emergency response and established their suitability for the recovery phase of disaster management by detecting damage to seawalls and piers, locating submerged debris (moorings and handrails), and determining safe lanes for sea navigation. It provides a preliminary domain theory of postdisaster port and littoral inspection with unmanned vehicles for use by the human-robot ...
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When steam generator tube denting was identified, steps were taken to retard the rate of corrosion and to develop corrective measures if possible. Techniques were developed to determine the exact shapes of the tubes, and procedures were devised to analyze resulting strain and operating stresses. Tube plugging criteria were established, and in twelve years of operation, there has been only one instance of a forced outage due to a tube leak.
This paper dealt with the identification of possible damaging mechanism of the collector of the WWER 440 steam generator, cracking of primary collectors, corrosion damage of the protective coat of the primary collector circumferential weld, cracking of breathing space in the region of blinding effect by corrosion and strain, leaking of disassembling joint of the primary collector lid and with the integrity of heat exchanging tubes.
The U. S. Department of Energy (DOE) is required by Comprehensive Environmental Response, Compensation, and Liability Act of 1980 regulations to develop a conceptual understanding of potential contaminant releases from the Hanford Site based on an evaluation of existing data and known historical practices. Polychlorinated biphenyls (PCBs) are one environmental contaminant potentially released through leaks, spills, or disposal. This document presents a summary of selected relevant existing information, including environmental studies and Hanford Site analytical data.
A technique has been developed for joining a large calcium fluoride crystal to a stainless-steel flange by means of a silver transition ring. The process involves both vacuum brazing using a copper-silver alloy and air brazing using silver chloride. This paper describes the procedure used in fabricating a high-vacuum leak-tight calcium fluoride window assembly.
This paper outlines aspects of the procedures adopted within Nuclear Electric plc for the assessment of Leak before Break arguments and the consequences arising from leakage and/or pipe failure. Only new aspects are considered such as creep, leakage, temperature and over pressure assessments and pipe whip. 7 refs.
This report provides a concise summary of the information collected and analyzed regarding the leak characteristics which define them as applicable candidates for pressure activated sealant technology. This information covers Office of Pipeline Safety reported incidents from 1985 to 1997 and was collected from existing data sources as well as operator and service company input.
This paper reports on the protection of opening that are exposed to the environment in nuclear facilities which presents an almost overwhelming engineering challenge. Intakes and outflows must permit the passage of large volumes of air or water without impeding their flow, and they are often exposed to corrosive salt and chemicals. An intrusion detection sensor that is intended to protect these openings must be capable of operating reliably under environmentally harsh conditions, and at the same time either provide a physical delay barrier or attach to an existing barrier. A new fiber optic sensor technology has now been developed specifically for protecting environmentally exposed openings. This sensor uses a fiber optic cable embedded in a neoprene rubber frame which is reinforced with Kevlar threads or braided steel cable. The sensor is configured in a mesh pattern with openings sufficiently large to permit air or water ...
Helically coiled tubes of steam generators (SG) in FBR are boundaries between sodium and water/steam. Therefore, to assure the integrity of tubes, it is necessary to inspect the tubes nondestructively for in service or after a sodium-water reaction accident. In order to make it possible to conduct in-service inspection of SG tubes, we have studied on eddy current probes and probe inserting methods. As for the probe inserting method, IHI designed a fluid driving type which consists of a model probe and signal cable with float balls and driven by air pressure force. Presented in this paper is the authors' report, which describes the fluid driving type as an effective method to insert an eddy current probe into helically coiled tubes. The outline of the test results is as follows: 1. It was possible to insert the probe into 65 meter length helically coiled tubes. 2. We could detected, as anticipated, a defect (outer ...
Quantitative trait loci (QTL) for growth traits, water use efficiency and tolerance/resistance against metals and herbivores have been identified. A hybrid F2 population originating from a cross between a Salix dasyclados-clone (SW901290) and a S. viminalis-clone ('Jorunn') was used for the different studies in this project. The growth response was analyzed in a greenhouse experiment with two water treatments, normal and drought. In addition, three field experiments with contrasting soils and climates were established. QTL specific for each treatment or field environment but also QTL stable over the treatments or field environments were detected. Each QTL explained from 8 to 29 % of the phenotypic variation depending on trait, treatment or field environment. Clusters of QTL for different traits were mapped indicating a common genetic base or tightly-linked QTL. Stable QTL identified for dryweight can be ...
A measurement of environmental radioactivity in Tokyo was started from 1974. We have been executing fixed time and fixed point observation since 1983 in Tokyo continuously. Measurement item is rain water, airborne dust, activated sludge at sewage treatment plants and external dose rate. Measurement data from 1983 to 1995 is reported in this paper. Moreover, we have been carried out the measurement of radon concentration in air from 1988 to 1991 in different types of residental buildings. The measurement results of rain water, airborne dust, external dose rate were approximately a background level respectively except for the Chernobyl nuclear power plant accident. Radionuclides used as radiopharmaceuticals were detected in the activated sludge at every sewage treatment plant but its concentration was lower than concentration limit in Japan. From a result of radon concentration measurements, there were no place which exceeds ...
This report discusses the development of transition metal oxide semiconductors for photoelectrolysis of water. More specifically, it involves preparation of TiO/sub 2/ films by sputtering and evaluating their physicochemical characteristics primarily as they relate to the behaviour of the films as photoanodes. Impedance, photoelectrochemical, and photoconduction properties of TiO/sub 2/ films sputtered in pure O/sub 2/ onto heated substrates have been determined as a function of O/sub 2/ pressure during sputtering, film thickness, Pt overcoating, and cathodic treatment. The capacitance data before cathodic treatment are of the form expected. The capacitance is essentially independent of potential, while for potentials increasingly cathodic of this value, the capacitance increases very rapidly. Cathodic treatment alters the impedance characteristics of the films but leads to either no detectible change in their photoelectrochemical properties or ...
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 ...
Leakage of CO{sub 2} and displaced brine from geologic carbon sequestration (GCS) sites into potable groundwater or to the near-surface environment is a primary concern for safety and effectiveness of GCS. The focus of this study is on the estimation of the probability of CO{sub 2} leakage along conduits such as faults and fractures. This probability is controlled by (1) the probability that the CO{sub 2} plume encounters a conductive fault that could serve as a conduit for CO{sub 2} to leak through the sealing formation, and (2) the probability that the conductive fault(s) intersected by the CO{sub 2} plume are connected to other conductive faults in such a way that a connected flow path is formed to allow CO{sub 2} to leak to environmental resources that may be impacted by leakage. This work is designed to fit into the certification framework for geological CO{sub 2} storage, which represents vulnerable resources such as potable groundwater, ...
For the study of radiation biology and its application to radiotherapy, the double differential cross section of electron emission from water vapor induced by 6.0 MeV alpha particle beam is measured. The energy spectra of electrons ranging 7- 10000 eV are detected by the electrostatic analyzer and micro channel plate. The measurements are made at angles between 20 and 160 degrees. With use of this data set, the radial dose distribution in water is calculated by using KURBUC code. It is the Monte Carlo type code of the electron transport process, where the track of the electron is simulated through each individual interactions including elastic scattering, ionization cross section and total excitation cross section in case that electrons with certain energy are put in the liquid-density water. In order to understand the effect of radiation when the particle flux is injected in the human body like ...
A novel continuous powder introduction microwave-induced plasma atomic emission spectrometry method (CPI-MIP-AES) has been developed for trace determination of metals in ground and tap water samples after preconcentration on activated carbon. The experimental setup consisted of integrated rectangular cavity TE_1_0_1 and vertically positioned plasma torch. The technical arrangement of the sample introduction system has been designed based on the fluidized bed concept. The satisfactory signal stability required for sequential analysis was attained owing to the vertical plasma configuration, as well as the plasma gas flow rate compatibility with sample introduction flow rate. The elements of interest (Cd, Cu, Cr, Fe, Mn, Pb, Zn) were preconcentrated in a batch procedure at pH 8-8.5 after addition of activated carbon and then, after filtering and drying of the activated carbon suspension, introduced to the MIP by the CPI system. An enrichment factor of about 1000-fold ...
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 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 ...
It has been concluded by geologists that a significant amount of hydrogen is stored as point defects in nominally anhydrous minerals. Determination of the amount of hydrogen bound in these minerals is a step towards determining the total water content of the earth mantle as well as comprehending its internal water cycle. The possibility to measure hydrogen in thin geological samples by elastic p-p scattering has been investigated at the Lund Nuclear Microprobe. In this work the development of the experimental procedure and standardisation of data analysis is described. Special emphasis has been put into doing the data analysis as simple as possible and at the same time applicable to all sorts of thin samples, even those of unknown nature. A special annular surface barrier detector composed of two insulated detector halves, which are read out simultaneously, is used to detect the recoiled proton and the scattered proton in ...
White spot syndrome virus (WSSV) is the causative agent of the white spot disease of shrimp. Penaeus monodon were captured from Muttukadu Estuary in Chennai, India, transported to the laboratory and maintained in an aerated system with continuous water circulation-biofiltration. WSSV-free P. monodon were challenged by feeding them only once with WSSV-infected tissues of P. monodon. Cumulative mortality (100%) of the infected individuals was determined. Tissues from infected and uninfected shrimp such as muscles, hepatopancreas, heart, gills and eye tissues (100mg of each) and haemolymph (50 microl) were subjected to SDS-PAGE. In infected muscle tissue, six newly expressed proteins were detected. In infected haemolymph, four new proteins and three intensely expressed high molecular weight proteins were observed. Three intensely expressed high molecular weight proteins were detected in infected heart tissue and two new ...
We present deep images of dust continuum emission at 450, 800, and 850 micron of the dark cloud LDN 1689N which harbors the low-mass young stellar objects (YSOs) IRAS 16293-2422A and B (I16293A and I16293B) and the cold prestellar object I16293E. Toward the positions of I16293A and E we also obtained spectra of CO-isotopomers and deep submillimeter observations of chemically related molecules with high critical densities. To I16293A we report the detection of the HDO 1_01 - 0_00 and H2O 1_10 - 1_01 ground-state transitions as broad self-reversed emission profiles with narrow absorption, and a tentative detection of H2D+ 1_10 - 1_11. To I16293E we detect weak emission of subthermally excited HDO 1_01 - 0_00. Based on this set of submillimeter continuum and line data we model the envelopes around I16293A and E. The density and velocity structure of I16293A is fit by an inside-out collapse model, yielding a sound speed of ...
The Helium and Lead Observatory (HALO) is a supernova neutrino detector under development for construction at SNOLAB. It is intended to fulfill a niche as a long term, low cost, high livetime, and low maintenance, dedicated supernova detector. It will be constructed from 80 tonnes of lead, from the decommissioning of the Deep River Cosmic Ray Station, and instrumented with approximately 384 meters of {sup 3}He neutron detectors from the final phase of the SNO experiment. Charged- and Neutral-Current neutrino interactions in lead expel neutrons from the lead nuclei making a burst of detected neutrons the signature for the detection of a supernova. Existing neutrino detectors are mostly of the water Cerenkov and liquid scintillator types, which are primarily sensitive to electron anti-neutrinos via charged-current interactions on the hydrogen nuclei in these materials. By contrast, the large neutron excess of a heavy nucleus ...
The R and D were carried out of a detecting system for measurement of data on the bottom of geothermal well, data transmission and signal processing, and an analysis system for well drilling trajectory control and well assessment while geothermal well drilling based on the data obtained by the detecting system. The paper reported the results of the technology development in fiscal 1996. In the development of the detecting system, improvement/design were conducted on a mud pulse generator constituting sonde, well bottom signal processing equipment, mode switch and inclined information sensor, and the system equivalent to the actual one was manufactured to conduct a running test at high temperature/pressure. Moreover, a test to confirm heat resistance of electronic parts was made for further improvement in heat resistance of the sonde, in order to obtain the data. In the development of an analysis system, conducted were ...
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The compost bioreactor ('anaerobic cell') components of three composite passive remediation systems constructed to treat acid mine drainage (AMD) at the former Wheal Jane tin mine, Cornwall, UK were studied over a period of 16 months. While there was some amelioration of the preprocessed AMD in each of the three compost bioreactors, as evidenced by pH increase and decrease in metal concentrations, only one of the cells showed effective removal of the two dominant heavy metals (iron and zinc) present. With two of the compost bioreactors, concentrations of soluble (ferrous) iron draining the cells were significantly greater than those entering the reactors, indicating that there was net mobilisation (by reductive dissolution) of colloidal and/or solid-phase ferric iron compounds within the cells. Soluble sulfide was also detected in waters draining all three compost bioreactors which was rapidly oxidised, in contrast to ferrous iron. Oxidation ...
The proton beam has an advantage of the sharp dose falloff in dose distribution called Bragg peak while conventional radiation therapy modalities such as photons exhibit considerable amount of exit dose. To take advantage of this property it is important to know the exact location of the distal dose falloff. An error can cause overdose to the normal tissue or underdose to the tumor volume. The only way of finding out the dose distribution in-situ in particle therapy is to measure the gammas produced by nuclear reactions with tissue materials. Two kinds of gammas can be used: one is prompt gamma and the other is coincident gamma from the positron-emission isotopes. We chose to detect prompt gammas, and developed a prompt gamma scanning system (PGS). The proton beams of the proton therapy facility at National Cancer Center were used. The gamma distribution was compared to the dose distribution measured by an ionization chamber at three different energies of 100, 150, ...
We present a thorough analysis of single atom detection using optical cavities. The large set of parameters that influence the signal-to-noise ratio for cavity detection is considered, with an emphasis on detunings, probe power, cavity finesse and photon detection schemes. Real device operating restrictions for single photon counting modules and standard photodiodes are included in our discussion, with heterodyne detection emerging as the clearly favourable technique, particularly for detuned detection at high power.
The history of explosives vapor detection includes almost every detection strategy known to man. Initial attempts to utilize these techniques were dismal failures. However, with the development of the Electron Capture Detector (ECD), the first promising detection of explosives vapors became possible. The present commercial explosives detectors detect the higher vapor pressure materials but not the whole spectrum. This paper describes the basic properties of explosives molecules and our research to utilize these properties for increased detection sensitivity.
In areas where radiation dose monitoring has not been performed, it is essential to use material available in the environment be able to rapidly assess doses to individuals for immediate emergency medical care or for general estimation of the radiological consequences. It was shown that certain types of telephone cards containing microchips have the potential to be used as individual radiation dosimeters in emergency situations to detect doses over 250 mGy by luminescence measurements. In order to understand the dosimetric properties of chip cards, the components obtained from INFINIEON Company at various stages of production were used for luminescence measurements. It is found that the protecting layer used above the chips so called 'globe top' is the main source of radiation induced signal in chip cards. The globe top produced by INFINIEON at that stage is found to contain SiO2 and Epoxy. In order to improve the dosimetric properties of the chip cards, the raw ...
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.
A Norwegian Research Program on Improved Oil Recovery (IOR) in North Sea reservoirs was launched in 1992. Microbial methods, applied in this context, is a part of this program. The scope, the methodological approach, and results from the three first years are presented. Water profile control, using biomass to block high permeable zones of a reservoir, has been investigated using nitrate-reducing bacteria in the injected sea water as plugging agents. Emphasis has been put on developing a process that does not have disadvantages secondary to the process itself, such as souring and impairment of the overall injectivity of the field. Data from continuous culture studies indicate that souring may successfully be mitigated by adding nitrite to the injected seawater. The morphology and size of generic-nitrate-reducing seawater bacteria have been investigated. Screening of growth-promoting nutrients has been carried out, and some sources were ...
The commercial solid phase microextraction (SPME) fibers are not stable enough in organic solvent and tend to swell and strip off from the silica fiber in the high performance liquid chromatography (HPLC) mobile phase, and therefore the application of SPME coupled online with HPLC is limited. In this study, an SPME fiber coated with single walled carbon nanotubes (SWCNTs), prepared by means of electrophoretic deposition, was coupled on line to HPLC for the determination of four endocrine-disrupting compounds, i.e. bisphenol A (BPA), estrone (E(1)), 17?-ethynylestradiol (EE(2)) and octylphenol (OP), in aqueous samples. The results showed that the SWCNTs coating on the prepared fiber did not swell and strip off from the platinum fiber throughout the experiment, thus indicating a high resistance to the HPLC mobile phase, the mixture of water and acetonitrile. The SWCNTs fiber had similar (for OP) or higher (for BPA, EE(2) and E(1)) extraction efficiencies than the ...
Polychlorinated n-alkanes (PCAs) are group of chemicals manufactured by chlorination of liquid n-paraffin or paraffin wax that contain 30 to 70% chlorine by weight. Large amounts of PCAs are widely used as plasticizers for vinyl chloride, lubricants, paints, and flame retardants and number of other industrial applications. Annual global production of PCAs is approximately 300 kilo tones, with a majority having medium-carbon-chain (C14-C19) length. According to the investigation made by Kagaku Kogyo Nippon-Sha, the annual consumption of PCAs in Japan was about 83,000 tons in between 1986-2001. Short-carbon-chain (C10-C13) has been placed on the Priority Substance List under Canadian Environmental Protection Act and on the Environmental Protection Agency Toxic Release Inventory in the USA due to its potential to act as tumor promoters in mammals. Data on environment levels of PCAs is meager, nevertheless, PCAs have been measured at relatively high concentrations in biota from Sweden, ...
The thermal dissolver, the main reactor of the SRC unit, has suffered a recurring problem. Specifically, it has been observed that whenever the reactor vessel is cooled to below 400/sup 0/F, its bottom head gasket leaks. An analysis of the thermal stress induced in the gasket, owing to transients across the bottom head flange, was sought. The analysis was facilitated by judiciously dividing a symmetric section of the reactor into 79 differential elements. Heat balances have been developed around each element. A numerical technique, the backward finite-difference approach, was employed to obtain the thermal behavior across the bottom head flange as a function of reactor heat-up time. The analysis performed affords an explanation for the failure of the gasket. Based on results of this work, recommendations have been suggested to provide the gasket and bolt stress requirements that are necessary to avoid leaks due to temperature changes.
The Time Projection Chamber (TPC) magnet at LBL and its compensation solenoids are adiabatically stable superconducting solenoid magnets. The cryogenic system developed for the TPC magnet is discussed. This system uses forced two-phase tubular cooling with the two cryogens in the system. The liquid helium and liquid nitrogen are delivered through the cooled load by forced tubular flow. The only reservoirs of liquid cryogen exist in the control dewar (for liquid helium) and the conditioner dewar (for liquid nitrogen). The operation o these systems during virtually all phases of system operation are described. Photographs and diagrams of various system components are shown, and cryogenic system data are presented in the following sections: (1) heat leaks into the TPC coil package and the compensation solenoids; (2) heat leaks to various components of the TPC magnet cryogenics system besides the magnets and control dewar; (3) the control dewar and ...
Various pollution abatement measures available to combat oil spills were reviewed with emphasis on biodegradation. Microorganisms naturally found in soils and groundwater can efficiently degrade a variety of organic contaminants. For certain sites, local temperature allows the microorganisms to reduce the contaminant concentrations without human intervention. In April 1994, a diesel fuel leak was found at a telecommunication station located in a park. The leak had already contaminated the surrounding soil. The first step of the clean-up procedure was to excavate the contaminated soil, followed by an evaluation to determine the extent of the remaining contamination. It was concluded that by using natural attenuation the deforestation of the remaining affected area could be prevented. In this instance, the natural attenuation process is expected to take five years for completion. 4 refs., 1 tab., 1 fig.
The fourth in a series of international Leak-Before-Break (LBB) Seminars supported in part by the US Nuclear Regulatory Commission was held at the National Central Library in Taipei, Taiwan on May 11 and 12, 1989. The seminar updated the international polices and supporting research on LBB. Attendees included representatives from regulatory agencies, electric utilities, nuclear power plant fabricators, research organizations, and academic institutions. Regulatory policy was the subject of presentations by Mr. G. Arlotto (US NRC, USA) Dr. B. Jarman (AECB, Canada), Dr.P. Milella (ENEA-DISP, Italy), Dr. C. Faidy (EDF/Septen, France ), and Dr. K. Takumi (NUPEC, Japan). A paper by Mr. K. Wichman and Mr. A. Lee of the US NRC Office of Nuclear Reactor Regulation is included as background material to these proceedings; it discusses the history and status of LBB applications in US nuclear power plants. In addition, several papers on the supporting research programs ...
Scaling criteria for a natural-circulation loop are examined. The present state of knowledge of scaling to obtain similarity during single- and two-phase flow conditions in a closed loop are reviewed, and an alternative development of two-phase similarity parameters is presented. The loop scaling criteria are the results of analyses in which flow from one component to another is considered. In this work, boundary conditions for the closed loop are developed to obtain scaling criteria for leak flow, injection flow, and heat loss to ambient. The leak scaling criteria are specialized for modeling approaches using prototypic fluid at prototypic or reduced pressures. The derived scaling parameters are examined for their application to two existing scaled test facilities: the Multi-Loop Integral System Test (MIST) facility at Babcock and Wilcox, and the UMCP 2 x 4 facility at the University of Maryland College Park. The heat loss similarity analysis ...
The purpose was to compare the findings of multi-detector computed tomography (MDCT) in prosthetic valve disorders using the operative findings as a gold standard. In a 3-year period, we prospectively enrolled 25 patients with 31 prosthetic heart valves. MDCT and transthoracic echocardiography (TTE) were done to evaluate pannus formation, prosthetic valve dysfunction, suture loosening (paravalvular leak) and pseudoaneurysm formation. Patients indicated for surgery received an operation within 1 week. The MDCT findings were compared with the operative findings. One patient with a Bjoerk-Shiley valve could not be evaluated by MDCT due to a severe beam-hardening artifact; thus, the exclusion rate for MDCT was 3.2% (1/31). Prosthetic valve disorders were suspected in 12 patients by either MDCT or TTE. Six patients received an operation that included three redo aortic valve replacements, two redo mitral replacements and one Amplatzer ductal occluder occlusion of a ...
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.
Results of an evaluation of 18 different products that can be used as waterstops in hydraulic dams to minimize or eliminate leaks at construction joints, were discussed. The materials were tested for permeability and adherence at 23, 15 and 5 degrees C. A two-component polyurethane resin product was found to be the one that best fulfilled the evaluation criteria. It was also found that the successful injection of a borehole depends not only on selecting the product with the best performance characteristics, but also on the technique used. Hence the preparation of the resin and the pressure at which it is injected are important performance criteria. 5 refs., 6 photos, 4 figs.
The second international conference on containment design and operation included sessions on the following topics: performance and regulatory requirements; radionuclide behaviour; severe accident design and analysis; operation, maintenance, leaking and aging of containment systems; thermal hydraulic behaviour of containment systems; hydrogen mixing and mitigation; design methods and concepts; code validation; structural analysis and response tests; passive safety systems; aerosol behaviour; containment reliability, integrity, and risk assessment; hydrogen deflagration and detonation. Due prominence was given to CANDU and other PHWR reactors. The individual papers have been abstracted separately.
Radioactive "1"4C sucrose was found to be an ideal marker for microleakage because it did not penetrate tooth tissue, dental cement, or mounting resin. The main finding is that the adhesive cements--the glass-ionomer and polycarboxylate--are significantly more effective at preventing microleakage than are the traditional phosphate cements--silicate and zinc phosphate. The differences can be as high as two orders of magnitude. The adhesive cements provide almost perfect and reliable seals. By contrast, the nonadhesive cements are erratic sealants with most of the restorations leaking.
To improve operational safety of the fuel channel for Wolsung units the recommended primary heat transport system (PHTS) operating guidelines were developed, which provides a safe operation window in terms of pressure and temperature to maintain fuel channel integrity, which is similar to pressure-temperature curves used for primary pressure boundary integrity in PWRs and deterministic Leak-Before Break (LBB) analyses were conducted using recent understanding of delayed hydride cracking (DHC) mechanism. In addition, a comparative assessment of LBB analysis was made using the procedures of Fitness For Service Guidelines(FFSG) for pressure tubes rev. 0 and rev. 1.
This paper presents the results of a model for the impact of potential contamination produced by radionuclide leaking due to long-term physical, chemical and hydrogeological processes occurring in a LILW repository and in the natural environment. The analysis contains a deterministic and also a probabilistic approach for uncertainty assessment. The input function, i.e., the source term was evaluated by using AMBER code and the entire analysis was accomplished by using GOLDSIM, a powerful tool to support probabilistic simulation in management and decision-making in engineering and science. The results obtained were compared to previous simulations and uncertainty analyses (FEHM). (authors)
The ubiquitous presence of mobile communication devices and the continuous development of mo- bile data applications, which results in high level of mobile devices' activity and exchanged data, often transparent to the user, makes privacy preservation an important feature of mobile telephony systems. We present a formal analysis of the UMTS Authentication and Key Agreement protocol, using the applied pi-calculus and the ProVerif tool. We formally verify the model with respect to privacy properties. We show a linkability attack which makes it possible, for individuals with low-cost equipment, to trace UMTS subscribers. The attack exploits information leaked by poorly designed error messages.
Plans, engineering parameters, and some test results for several FFTF core and primary sodium circuit instrument systems are presented. The systems discussed include temperature, flow, pressure, leak detectors, level sensors, fuel failure monitoring, sodium impurity analysis and cover gas monitors. Since many of these instruments are similar to those used in other fast reactors around the world, only a brief description is presented for these systems. Results of recent demonstration tests of the FFTF Under-Sodium Viewing and Ranging system are also presented. (U.K.).
A fuel plate examination was conducted in the hot cell and canal to determine the possible failure modes for three plates leaking fission products. The plates were irradiated in the Extended Life Aluminide Fuel (ELAF) program in support of university research reactor goals to increase the limits presently allowed. The examination indicated pitting corrosion to be the failure mode. Other failure modes such as: (a) nonbonded swelling, (b) excessive fuel swelling, and (c) overheating of the plates were not observed.
The role of robotics and remote handling equipment in future nuclear power plant maintenance activities is discussed in the context of artificial intelligence applications. Special requirements manipulators, control systems, and man-machine interfaces for nuclear applications are noted. Tasks might include inspection with cameras, eddy current probes, and leak detectors; the collection of material samples; radiation monitoring; and the disassembly, repair and reassembly of a variety of system components. A robot with vision and force sensing and an intelligent control system that can access a knowledge base is schematically described. Recent advances in image interpretation systems are also discussed.
The role of robotics and remote handling equipment in future nuclear power plant maintenance activities is discussed in the context of artificial intelligence applications. Special requirements manipulators, control systems, and man-machine interfaces for nuclear applications are noted. Tasks might include inspection with cameras, eddy current probes, and leak detectors; the collection of material samples; radiation monitoring; and the disassembly, repair and reassembly of a variety of system components. A robot with vision and force sensing and an intelligent control system that can access a knowledge base is schematically described. Recent advances in image interpretation systems are also discussed.
Waste tank W-12 is a tank in the ORNL Low-Level Liquid Waste (LLLW) system that collected waste from Building 3525. Because of a leaking flange in the discharge line from W-12 to the evaporator service tank (W-22) and continual inleakage into the tank from an unknown source, W-12 was removed from service to comply with the Federal Facilities Agreement requirement. The initial response was to decontaminate the valve pit between tank W-12 and the evaporator service tank (W-22) to determine if personnel could enter the pit to attempt repair of the leaking flange. Preventing the spread of radioactive contamination from the pit to the environment and to other waste systems was of concern during the decontamination. The drain in the pit goes to the process waste system; therefore, if high-level liquid waste were generated during decontamination activities, it would have to be removed from the pit by means other than the available liquid waste ...
Full text.Surficial sediment samples were collected from seventeen springs distributed all over Lebanon (east, west, north and south). Concentrations of metals Ca, Fe, Mn, Ni, Cu, Cr, Zn and Pb were determined by energy dispersive x-ray fluorescence technique. Irradiation was done by the radioisotope source Cd-109 and the detection by an EG and G Si(Li) detector. These analysis was done in attempt to assess the impact of anthropogenic sources on ground water quality. Metals concentration in sediment were found to be (Ca:0.05-47%, Fe:0.24-4.2%, Cr:
Pyrethroid pesticides occur in urban creek sediments at concentrations acutely toxic to sensitive aquatic life. To better understand the source of these residues, runoff from residential neighborhoods around Sacramento, California was monitored over the course of a year. Pyrethroids were present in every sample. Bifenthrin, found at up to 73 ng/L in the water and 1211 ng/g on suspended sediment, was the pyrethroid of greatest toxicological concern, with cypermethrin and cyfluthrin of secondary concern. The bifenthrin could have originated either from use by consumers or professional pest controllers, though the seasonal pattern of discharge from the drain was more consistent with professional use as the dominant source. Stormwater runoff was more important than dry season irrigation runoff in transporting pyrethroids to urban creeks. A single intense storm was capable of discharging as much bifenthrin to an urban creek in 3 h as that discharged over 6 months of ...
Abstract in english The tegument surface of the adult schistosome, bounded by a normal plasma membrane overlain by a secreted membranocalyx, holds the key to understanding how schistosomes evade host immune responses. Recent advances in mass spectrometry (MS), and the sequencing of the Schistosoma mansoni transcriptome/genome, have facilitated schistosome proteomics. We detached the tegument from the worm body and enriched its surface membranes by differential extraction, before subjecting t (more) he preparation to liquid chromatography-based proteomics to identify its constituents. The most exposed proteins on live worms were labelled with impearmeant biotinylation reagents, and we also developed methods to isolate the membranocalyx for analysis. We identified transporters for sugars, amino acids, inorganic ions and water, which confirm the importance of the tegument plasma membrane in nutrient acquisition and solute balance. Enzymes, including phosphohydrolases, ...
KM3NeT is a future deep-sea research infrastructure hosting a neutrino telescope with a volume of at least one cubic kilometer to be constructed in the Mediterranean Sea. The experiment aims to detect high-energy cosmic neutrinos using a 3D array of optical modules to collect the Cherenkov light induced by charged particles in the water. Upward going muons and showers produced in neutrino interactions with the surrounding matter will allow the search and study of possible sources of extra-terrestrial neutrinos. The design of optical modules makes an important impact on the performance and cost of the KM3NeT project. Several different optical module configurations are under consideration; based on glass pressure spheres containing: a large (10 in.) hemispherical photomultiplier tube (with a multi-anode version as an option); 25-31 3 in. photomultiplier tubes, or a crystal scintillator-based hybrid device (X-HPD). The features and advantages of ...
The paper reported on an experiment on measurement of concentration of highly concentrated coal slurry using microwaves carried out at Miike coal preparation works. The purpose of the experiment was to investigate applicability of microwave moisture content measurement of slurry of a mixture of coal and coal particles and to use it to the control of process such as coal preparation and processing. In the experiment, a method for measuring the slurry concentration was adopted in which the container filled with highly concentrated coal slurry was irradiated with microwaves and the damping of strength of the penetrating microwaves was detected. As a result of the experiment, it was found out that there was a big correlation between the capacitive concentration of slurry and the damping ratio of microwaves. When irradiating slurry with microwaves of 1GHz frequency, a big correlation between the concentration and the damping ratio was seen in capacitive concentration of ...
Traditional laboratory diffusion experiments in rock material are time consuming, and quite small samples are generally used. Electrical conductivity measurements, on the other hand, provide a fast means for examining transport properties in rock and allow measurements on larger samples as well. Laboratory measurements using electrical conductivity give results that compare well to those from traditional diffusion experiments. The measurement of the electrical resistivity in the rock surrounding a borehole is a standard method for the detection of water conducting fractures. If these data could be correlated to matrix diffusion properties, in-situ diffusion data from large areas could be obtained. This would be valuable because it would make it possible to obtain data very early in future investigations of potentially suitable sites for a repository. This study compares laboratory electrical conductivity measurements with in-situ resistivity ...
Gas transmission pipelines are susceptible to both internal (gas side) and external (soil side) corrosion attack. Internal corrosion is caused by the presence of salt laden moisture, CO{sub 2}, H{sub 2}S, and perhaps O{sub 2} in the natural gas. Internal corrosion usually manifests itself as general corrosion. However, the presence of chlorides in entrained water also can lead to pitting corrosion damage. The electrochemical noise technique can differentiate general from localized corrosion and provide estimates of corrosion rates without external perturbation of the corroding system. It is increasingly being applied to field and industrial installations for in situ corrosion monitoring. It has been used here to determine its suitability for monitoring internal and external corrosion damage on gas transmission pipelines. Corrosion measurements were made in three types of environments: (1) aqueous solutions typical of those found within gas pipelines in equilibrium ...
This study evaluates the correlation between transplanted Asiatic clam and indigenous community responses to acid mine drainage and nutrient loading in first-to-third-order streams, by comparing the toxicological endpoints of clam survival and growth with benthic macro-invertebrate community indices as community responses to both acid mine drainage and nutrient loading. Clam survival was found to be positively correlated with water column pH and negatively correlated with conductivity and metal concentrations. There was also a positive correlation with the relative abundance of the macro-invertebrate Ephemeroptera, the most sensitive taxonomic group, to acid mine drainage in this watershed. No correlation was found between clam growth and acid mine drainage inputs, but there was evidence of positive correlation with nitrate concentrations and the relative abundance of collector-filterer functional feeding groups. These results suggest that clam growth is related to ...
A combination of /sup 18/O-labeling experiments and kinetic studies to clarify the nonenzymatic hydrolytic pathways of adenosine 5'-triphosphate (ATP) at pH values ranging from 0 to 8.3 has been used in this experiment. In 1 N and 0.1 N HCl, the data are consistent with the hypothesis that hydrolysis occurs by addition-elimination, with initial attack 93% ..gamma.. and 7% ..beta..; both lead only to ADP + P/sub i/. In the subsequent hydrolysis of the ADP to AMP + P/sub i/, attack is 83% ..beta.. and 17% ..cap alpha... At pH 8.3, the data are consistent with the hypothesis that hydrolsysis occurs by elimination-addition. Over the entire pH range studied, no oxygen exchange between water and ATP, ADP, or P/sub i/ was detected. Nonenzymatic hydrolysis and isotopic analysis of the resultant P/sub i/ comprise a preferred means of assaying the isotopic enrichment of (..gamma..-/sup 18/O)ATP to be used in studies of enzymatic processes.
A new spectrofluorimetric method was developed for the determination of trace amount of nicotinamide adenine dinucleotide phosphate (NADP). Using europium (Eu{sup 3+})-tetracycline (TC) complex as a fluorescent probe, in the buffer solution of pH 7.60. NADP can remarkably enhance the fluorescence intensity of the Eu{sup 3+}-TC complex at {lambda} = 612 nm and the enhanced fluorescence intensity of Eu{sup 3+} ion is in proportion to the concentration of NADP. Optimum conditions for the determination of NADP were also investigated. The dynamic range for the determination of NADP is 4.4 x 10{sup -7} to 2.2 x 10{sup -6} mol l{sup -1} with detection limit of 6.9 x 10{sup -8} mol l{sup -1}. This method is simple, practical and relatively free interference from coexisting substances and can be successfully applied to determination of NADP in synthetic water samples and in serum samples. Moreover, the enhancement mechanisms of the fluorescence ...
New physical objects, ispalators based on free soap films, exhibit persistent flows of the soap solution in open and closed volumes in air with additions of gases of the C_8F_1_8 type (p = 20 Torr) at temperature drops on the films of the order of tenths and hundredths of kelvin. The flows move continuously at a velocity of 5 - 20 cm s"-"1. It is found that the parts of an inclined ispalator film show anomalous behaviour upon heating: their weight increases and they move downward over the film, whereas the unheated parts of the film move upward. Continuous radial vortex flows accompanied by the formation and washing of the regions of a thin black film are observed on circular films in closed volumes upon their uniform external cooling by evaporating water for 5 - 10 hours. The rapid flows make film ispalators the efficient heat carriers, which operate at small temperature drops (tenths and hundredths of kelvin) and surpass copper in the amount of thermal energy ...
In this study, growth measurements of fatigue cracks in air and various simulated media for steam turbines were made by means of rupture-mechanical methods. In this connection, it was detected that even pure water leads to a clear increase in the fatigue crack rates of low-pressure rotor steels. In this connection, it was striking to observe that the crack propagation velocities at 100"0C were higher than at 160"0C. It is probable that the kinetics of the film formation at the crack tip was of importance. The inhibiting effect of the alkaline solutions is explained by the increasing stability of a film of Fe(OH)_2 at an increased pH value. Neither the frequency response nor the fractographic result indicate an influence of the stress crack corrosion. This can be explained by the fact that the incubation period (= the period to initiate an intercrystalline crack caused by stress crack corrosion at a transcrystalline fatigue crack tip) in the ...
A novel method for the determination of metoclopramide (MCP) using electrogenerated chemiluminescence (ECL) is presented. A tris(2,2prime-bipyridyl)dichlororuthenium(II) (Ru(bpy)32+)-doped silica (RuDS) nanoparticle/perfluoinated ion-exchange resin (Nafion) with nanocomposite membrane modified glassy carbon electrode (GCE) is used. The Ru(bpy)32+ encapsulation interior of the silica nanoparticle maintains its electrochemical activities and also reduces Ru(bpy)32+ leaching from the silica matrix when immersed in water due to the electrostatic interaction. The analytical performance of this ECL sensor for MCP is shown in detail. Under optimal experimental conditions, it has good linearity in the concentration range from 2x10-8mol/L to 1x10-5mol/L (R=0.9989) with a detection limit of 7x10-9mo...
This paper indicates first that the base content in desert soil is by far much higher than that in soils in moist areas, that salts with the higher solubility to water have their deposition depth greater, and that the organic content is extremely low. The paper also describes the experiments to verify that the desert soil contains soil lumps with a diameter of about several millimeters, which function effectively to form the long term survival locations for microorganisms. Desert soil containing soil lumps and the one removed of lumps by pulverizing them into powder were prepared as test specimens, which were left submerged. It was confirmed that the velocity of decomposing the organics and the mechanical strength in the latter soil are obviously inferior to those in the former soil. Additional remarks are given that when the desert soil environment is changed the microorganisms get more active appreciably and that certain kinds of mold fungi and green algae were ...
Penicillium crustosum is common in food and feed both in subtropical and temperate regions. Recently, it has also been found occurring frequently in glacier ice, sea ice and sea water of Arctic regions of Svalbard. The aim of the study was to compare isolates of the same fungal species from widely different habitats and geographic regions to see if the nutritional physiology and the profile of secondary metabolites were consistent or depended on the isolation source. All 121 strains examined produced the following families of secondary metabolites: penitrems (100%), roquefortines (100%), terrestric acids (99.2%) and viridicatols (100%), whereas 81 of 83 Arctic isolates additionally produced andrastin A. However, only 8 of 38 non-Arctic isolates produced detectable andrastin A. The quantitative profiles of 96 strains were compared using cluster, principal component and correspondence analyses. There was no clear grouping of Arctic versus ...
The oceanic phytoplancton productivity may essentially influence the total rate of the atmospheric CO{sub 2} absorption by the ocean - that is, a considerable amount of CO{sub 2} will be taken-up in the 50 micrometers thick layer near the air-sea interface. Even if phytoplancton production constitutes only 5% of the total oceanic biota production, this will increase the rate of CO{sub 2} absorption more than twice compared with the present estimates. The reason is that metabolic activity of phytoplancton leads to the emergence in a thin scin (50 micrometers, the average size of phytoplancton cells) layer near the water surface of an additional minimum in the CO{sub 2} partial pressure profile and of an additional maximum of {Delta} {sup 13}C in the same area. These two extremums cannot be detected if the corresponding characteristics are averaged over any microscopic area in the well mixing layer that is more than 1 meter deep, which is usually ...
A reactor-neutrino experiment, Daya Bay, has been proposed to determine the least-known neutrino mixing angle theta_13 using electron antineutrinos produced at the Daya Bay nuclear power complex in China. Daya Bay is an international collaboration with institutions from China, the United States, the Czech Republic, Hong Kong, Russia, and Taiwan. The experiment will use eight identical detectors deployed at three different locations optimized for monitoring the antineutrino rates from the six reactors and for detecting any rate deficit and spectral distortion near the first oscillation maximum. The overburden of the under ground experimental halls, connected with tunnels, ranges from about 250 to 900 meters-water-equivalent so that the cosmogenic background is small compared to the number of observed antineutrino events. Civil construction of tunnels and experimental facilities is planned to start in 2007, with detector construction beginning in ...
Organic waste, as a main constituent of municipal solid waste, has as well as solid biomass a high potential for biogas generation. Despite the importance of biogas generation from these materials, the availability of large-scale biogas processes lacks behind the demand. A newly developed double-stage solid-liquid biogas process, consisting of an open hydrolysis stage and a fixed-bed methane reactor, allows the biogas production from almost all biodegradable solid waste and renewable resources like maize, grass, sugar cane, etc. Furthermore, residues from industrial processes, like the glycerine waste water from biodiesel production, can also be converted into biogas successfully. Due to the strong separation of hydrolysis and methanation, the process is extremely stable. No malfunction has been detected so far. The open hydrolysis releases CO_2 and allows oxidation of sulfur. Consequently, the biogas has a high methane (>72%) and low H_2S ...
We have conducted an investigation to determine the occurrence and distribution of erionite, a potential carcinogen, at Yucca Mountain, Nevada. Using x-ray powder diffraction techniques yielding detection limits to below 0.05 wt %, we positively identified erionite in only 3 out of 76 bulk and 12 fracture samples investigated. The three erionite-bearing samples (J12-620/630, UE-25aNo.1-1296.2, and USW G4-1314) all occur above the static water level in clay/zeolite-rich horizons near the top of vitrophyres. Erionite occurs as trace amounts of less than 1 wt % in the whole rock, although it may occur locally in significant amounts as fracture fillings (e.g., UE-25aNo.1-1296.2 where it comprises approximately 45 wt % of the fracture filling material). All three occurrences appear to be extremely isolated cases since erionite was not detected in neighboring samples. Erionite at Yucca Mountain apparently formed only in localized ...
In 1996, the National Marine Fisheries Service and the University of Washington completed the fourth year of a multi-year study to estimate survival of juvenile salmonids (Oncorhynchus spp.) passing through dams and reservoirs on the Snake River. Actively migrating smolts were collected near the head of Lower Granite Reservoir and at Lower Granite Dam, tagged with passive integrated transponder (PIT) tags, and released to continue their downstream migration. Individual smolts were subsequently detected at PIT-tag detection facilities at Lower Granite, Little Goose, Lower Monumental, McNary, John Day and Bonneville Dams. Survival estimates were calculated using the Single-Release (SR) and Paired-Release (PR) Models. Timing of releases of tagged hatchery steelhead (O. mykiss) from the head of Lower Granite Reservoir and yearling chinook salmon (O. tshawytscha) from Lower Granite Dam in 1996 spanned the major portion of their juvenile migrations. ...
The detection, in European steam generators, of intergranular stress corrosion cracking initiating from the primary side (PWSCC) and the somewhat similar detection of intergranular stress corrosion (IGSCC) and intergranular corrosion (IGA) initiated from the secondary side in Japanese steam generators has led to a growing awareness of the potential for such corrosion forms in United States PWR steam generators. What had been a minor occurrence at several units is now a cause of concern and repair measures at more than 30 sites in the United States, and in some cases, is the major cause of steam generator unavailability. The United States nuclear utilities and EPRI formed the first Steam Generator Owners' Group (SGOG) in 1977 in response to the prospect of continued denting corrosion. The occasional appearance of PWSCC, IGSCC and IGA in domestic steam generators was not a sufficient cause for initiating an extensive research program in SGOG I. ...
Determination, uptake and distribution of various ions such as alkali metals in three different parts (leaf, stem and root) and seeds of radish (Kaiware daikon) were examined using flame emission spectrometry and ICP-AES. In order to examine the influence of concentration alkali metal ion concentration in the radish culture solution on the uptake and distribution of these metals, the radish was grown at pH 5.6 in solutions containing alkali metal chloride at concentrations ranging from 10{sup -5} to 10{sup -1} mol dm{sup -3}. When the radish were grown in culture solution with alkali metal ions of low concentrations (10{sup -5} and 10{sup -4} mol dm{sup -3}), Na, K, Rb and trace Li were detected in leaves, stems and roots while Cs was scarcely detected. However, the contents of Na, K, Li in these organs were the same as those in radish cultivated in pure water. An increase of Rb uptake was observed with an increased Rb ...
A small-sized inexpensive carbon dioxide gassensor was prepared using LiTi2 (PO4)3 +0.2Li3PO4 as lithium-ion conductive, solid electrolyte and its detectability and the effects of co-existing gases were examined. The above compound was obtained by the method where a powdery mixture of Li2CO3, TiO2, (NH4)H2PO4 and Li3PO3 was molded in the presence of a sintering assistant, subjected to hydrostatic press, and sintered. Measurements were made on the relation between CO2 concentration and the electromotive force of the CO2 sensor made of the compound and the influence of concentration of coexisting NO2, SO2 or CH4 on the electromotive force. The results are summarized as follows. A linear relation exists between the electromotive force and the CO2 concentration in the range from 80ppm to 1% to show a good agreement between theoretical and experimental results. Coexistence of NO2 the range of 100-4500ppm has no influence on the electromotive force. Coexistence of ...
Behavioral detection of a low-frequency (40 Hz) vibratory dipole at source distances of 1.5–24 cm was measured by classically conditioned respiratory suppression in goldfish (Carassius...Full Text Available
Bone metastases of an Ewing's sarcoma were detected by magnetic resonance imaging (MRI), when bone scan, CT and plain films were still normal. This is due to the ability of MRI to detect intramedullary metastases before involvement of the cortex. (Auth.).
Since current microbiology methods are not suitable to detect Clostridium perfringens in formalin-fixed, paraffin-embedded tissue samples, we developed a PCR assay to detect toxin-encoding...Full Text Available
Denaturing high-performance liquid chromatography (DHPLC) has been used extensively to detect genetic variation. We used this method to detect and identify Yersinia pestis KIM5 ciprofloxacin-resistant...Full Text Available
This work describes the radon in soil gas measurements performed during the last two years in cooperation between the Laboratory of Applied Nuclear Physics of the Federal University of Technology (UTFPR), the Nuclear Technology Development Center (CDTN) and the Institute of Radiation Protection and Dosimetry (IRD) from the Brazilian Nuclear Energy Commission (CNEN). Following previously concluded measurements of radon concentration in dwellings and the measurements of 222Rn activity in drinking water collected at artesian bores of Curitiba urban area, present step of activities has been dedicated to measurements of radon concentration in soil gas. Experimental setup was based on the Professional Radon Monitor (ALPHA GUARD) connected to specially developed for such measurements Soil Gas Probe through the air pump and filter system. After the Probe was inserted, the ground has been tamped down around the probe, to prevent air from moving vertically along the outside ...
Field studies were conducted May 28-June 1, 1979, to determine the chemical composition and physical behavior of discharges from an offshore gas drilling rig in the central basin of Lake Erie. The drilling operation was observed for four days, from rig jackup to the circulation of mud through the borehole after drilling had been completed. Resuspension studies using nephelometry, supplemented with chemical analyses, indicated little resuspension of lake bottom materials or release of metals to the water column during rig jack-up. Portions of the turbidity plumes generated during drilling were buoyant. Three surface turbidity plumes were mapped with nephelometry to a point at which particulate concentrations reached background levels in the Lake. Detectable plumes were approx. 400 to 1500 m in length and had maximum widths < 230 m. A chemical survey conducted in the plume during early gas shows indicated that discharged inorganic chemical ...
The use and application of remote sensing data for monitoring the environmental impacts of open cast lignite mining in Eastern Germany is described. This investigation is based on the digital analysis of several Landsat-TM and ERS-1 data sets acquired from 1989 to 1994. The characteristics of the imagery enable quantitative analysis of different open cast mine features, such as waste, water bodies, change of land use, reclamation processes and estimation of vegetation cover in the affected areas. On the basis of the Maximum Likelihood Classification of Landsat Thematic Mapper (TM) data the open cast mining areas were separated into bare open cast areas and areas of less and dense vegetation. The bare open cast areas were classified with respect to type of different sediments and the vegetation was seperated into different classes according to the age of the vegetation and the density cover. Apart from these, water bodies within the mining areas ...
A study on oxygen-plasma treatment of ink-jet paper is presented. Paper was exposed to a weakly ionized, highly dissociated oxygen plasma with an electron temperature of 5 eV, a positive-ion density of 8 x 1015 m-3 and a density of neutral oxygen atoms of 5 x 1021 m-3. Optical emission spectroscopy (OES) was applied as a method for detection of the reaction products during the plasma treatment of the paper. OES spectra between 250 and 1000 nm were measured continuously during the plasma treatment. The wettability of the samples before and after the plasma treatment was determined by measuring the contact angle of a water drop. The appearance of the surface-functional groups was determined by using high-resolution x-ray photoelectron spectroscopy (XPS), while changes in the surface morphology were monitored with scanning electron microscopy (SEM). Already after 1 s of the plasma treatment the surface, which was originally hydrophobic, changed to ...
Dissolved humic substances (humic and fulvic acids) occur in surface waters and groundwaters in concentrations ranging from less than 1 mg(C)/L to more than 100 mg(C)/L. Humic substances are strong complexing agents for many trace metals in the environment and are also capable of forming stable soluble complexes or chelates with radionuclides. Concentrations of humic materials as low as 1 mg(C)/L can produce a detectable increase in the mobility of some actinide elements by forming soluble complexes that inhibit sorption of the radionuclides onto rock materials. The stability of trace metal- or radionuclide-organic complexes is commonly measured by an empirically determined conditional stability constant (K'), which is based on the ratio of complexed metal (radionuclide) in solution to the product concentration of uncomplexed metal and humic complexant. Larger values of stability constants indicate greater complex stability. The ...
Alkaline promoted active carbon supported iron catalysts are very active in the oxidative dehydrogenation of ethylbenzene to styrene in the presence of carbon dioxide. The best results were obtained at 550 C for a Li-promoted catalyst with a conversion of ethylbenzene of 75% and a selectivity towards styrene of nearly 95%. These results are better than those obtained with industrial catalysts which perform the dehydrogenation process with an excess of water. The main product of the dehydrogenation reaction with CO{sub 2} was styrene, but the following by-products were detected - benzene and toluene. The selectivity towards toluene was always higher than towards benzene. We observed also the formation of carbon monoxide and water, which were produced with a constant molar ratio of about 0.8. The weight of the catalysts increased up to 20% during the reaction due to deposition of carbon. Using a too large excess of CO{sub 2} ...
Anionic complexes of transition metals were stabilized in aqueous solutions containing high concentrations of various short-chain quaternary ammonium salts. Compounds with longer paraffin chains were effective in much less concentrated solution. Complex ions were detected spectrophotometrically. FeCl/sub 4//sup -/, which is usually formed in concentrated HCl, was the predominant Fe(III) complex in 30 m choline chloride containing only 0.12 M HCl. A yellow transitory Tc(VII) chloro-addition intermediate, formed in the reduction of TcO/sub 4//sup -/ by concentrated HCl, was stabilized when the solution also contained 25 m choline chloride. Its spectrum, as well as the isolation of an already known Tc(VII) bipyridyl complex, is reported. Concentrated organic electrolytes also stabilized Tc(V) oxide halides against disproportionation and Tc(IV) hexahalides against hydrolysis. Halochromates of Cr(VI) were formed and stabilized in dilute acid containing quaternary ...
Analytical expressions that describe the dependence of slopes and amplitudes of the scatter distribution functions (SDF) on source depth and media density are used to estimate a scatter component in SPECT projection data. Since the ratio of detected scattered to total photons (S/T), SDF amplitude and slope depend strongly on line source length (SL) used to obtain SDFs, we compared estimated scattered components using SDFs, obtained for lengths of 2-21 cm. At 10 cm source depth, S/T changes from 0.19 to 0.36 when SL changes from 2 to 21 cm. Scatter amplitude`s dependence on source depth (d) in water was described by 6.38e{sup -0.186d} for a 2 cm and 16.15e{sup -0.129d} for a 21 cm SL. Slope was described by 0.292d{sup -0.601} for a cm SL and by 0.396d{sup -0.82} for a 21 cm SL. The estimated scatter components are compared with simulated SPECT projection data obtained with Monte Carlo modeling of six hot spheres placed in a cylindrical ...
Three blocks of non-welded tuff, one nominally one cubic foot (trial block) and the other two, nominally one cubic metre (1 m{sup 3}), were excavated from the Busted Butte Test Facility on the Nevada Test Site and transported to the Atomic Energy of Canada Limited Whiteshell Laboratories in Pinawa, Manitoba. The trial block and one of the 1-m{sup 3} blocks were used for unsaturated flow experiments. The remaining 1-m{sup 3} block is being used for saturated flow experiments and will be reported on separately. After a vertical flow of synthetic transport solution was set up under unsaturated conditions, a suite of conservative and chemically reactive radionuclide tracers was injected at volumetric flow rates of 20 mL/hr in the trial block, and 10 mL/hr in the 1-m{sup 3} block. The duration of the migration experiment in the trial block was 87 days, while the migration experiment in the 1-m{sup 3} block was continuing after 600 days. Results obtained from the migration experiment in the ...
Arsenic was predominantly present as inorganic arsenite in the fronds of the hyperaccumulator Chinese brake. - Arsenic speciation is important not only for understanding the mechanisms of arsenic accumulation and detoxification by hyperaccumulators, but also for designing disposal options of arsenic-rich biomass. The primary objective of this research was to understand the speciation and leachability of arsenic in the fronds of Chinese brake (Pteris vittata L.), an arsenic hyperaccumulator, with an emphasis on the implications for arsenic-rich biomass disposal. Chinese brake was grown for 18 weeks in a soil spiked with 50 mg As kg"-"1 as arsenate (AsO_4"3"-), arsenite (AsO_3"3"-), dimethylarsinic acid (DMA), or methylarsonic acid (MMA). Plant samples were extracted with methanol/water (1:1) and arsenic speciation was performed using high performance liquid chromatography coupled with atomic fluorescence spectrometry. The impacts of air-drying on arsenic species and ...
Here we describe the fabrication, optimization, and application of a microfluidic device that integrates microdialysis (MD) sampling, microchip electrophoresis (ME), and electrochemical detection...Full Text Available
on this technology has beenproposedas a payload on SpaceStation Freedom to be launched in the near future [1]. Direct detection 4-ary pulse position modula- ...
Due to the serovar diversity in Haemophilus (H.) parasuis, it is difficult to develop a universal serological method for detection of this pathogen....Full Text Available
Microcalcifications in mammogram have been mainly targeted as a reliable earliest sign of breast cancer and their early detection is vital to improve its prognosis. Since their size is very small and may be easily overlooked by the examining radiologist, computer-based detection output can assist the radiologist to improve the diagnostic accuracy. In this paper, we have proposed an algorithm for detecting microcalcification in mammogram. The proposed microcalcification detection algorithm involves mammogram quality enhancement using multirresolution analysis based on the dyadic wavelet transform and microcalcification detection by fuzzy shell clustering. It may be possible to detect nodular components such as microcalcification accurately by introducing shape information. The effectiveness of the proposed algorithm for microcalcification ...
Palladium chloride films have been found to be useful as ... when suitably prepared palladium chlo- ride films are exposed ... Like the palladium chloride ( PdCl2) ...
BackgroundAutofluorescence bronchoscopy is more sensitive than conventional bronchoscopy for detecting early airway mucosal lesions. Decreased specificity can lead...Full Text Available
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 Wendelstein 7-X (W7-X) modular stellarator is under construction at the Max-Planck-Institut fur Plasmaphysik in Greifswald, Germany. The W7-X magnet system contains 70 coils made up from helium cooled superconducting cables in aluminium alloy (EN AW-6063) jackets. Several hundred connections of the jacket to the cable joints are made by aluminium-to-aluminium welds. Due to geometrical and thermal boundary conditions these welds cannot be accomplished free from defects. Microscopic analyses of the welds show that a variety of small flaws such as cracks and pores develop during welding. The welds have thus to be dimensioned accordingly, and appropriate weld qualification, investigation and testing has to be done in order not to jeopardise the structural integrity and leak tightness. The ...
Aim: To evaluate the usefulness of routine laboratory parameters in the decision to treat refractory cardiac arrest patients with extracorporeal life support (ECLS). Methods: Sixty-six adults with witnessed cardiac arrest of cardiac origin unrelated to poisoning or hypothermia undergoing cardiopulmonary resuscitation without return of spontaneous circulation (duration: 155min [120-180], median, [25-75%-percentiles]) were included in a prospective cohort-study. ECLS was implemented under cardiac massage, using a centrifugal pump connected to a hollow-fiber membrane-oxygenator, aiming to maintain ECLS flow >=2.5l/min and mean arterial pressure >=60mmHg. Results: Forty-seven of 66 patients died within 24h from multiorgan failure and massive capillary leak. Of 19/66 patients who survived >=24h...
Seventy-one patients with intestinal injury secondary to pelvic irradiation had predominantly large bowel lesions. Seventeen cases were treated conservatively and 54 came to surgery, 28 patients having more than one operation. Following this essentially salvage surgery there were more ileal than colonic anastomotic leaks. Thirty-four patients died during the follow-up period (2-12 years), 19 from recurrent malignancy, and nine as a result of continuing radiation effects. Seventy per cent of the patients who had a radiation fistula died as a result of malignancy. Of 42000 cases of pelvic malignancy treated by irradiation over the decade 1972-1982, surgical referrals for complications constituted 1.7%, with an overall radiation-related mortality of 0.2%. It is our opinion that colostomy alone has little part to play in this condition, and a policy based on excisional surgery is suggested.
We examine the short-term price behaviour of three, size-conditioned Indian stock market indices, in response to informational shocks. A standard mean-adjusted returns model as well as the GJR-GARCH specification point towards underreaction to negative events in the medium and small capitalization indices. Also, the pre-event coefficients are generally negative and statistically significant, regardless of the sign of the shock, thus ruling out information leaks. We uncover a stable abnormal volatility pattern which increases monotonically a few days before the shock before suddenly decreasing in magnitude on the event day and beyond. We suggest uncertainty avoidance as a potential explanation of these features. The results are fairly robust across alternative event selection procedures, ti...
UO/sub 2/ definitely leaked past the O-ring in three of the tests confirming the major results of the previous work. Continuous leakage at these levels may require additional precautions under present regulatory policies. The mechanism and the time and particle size dependence for the leakage are not known, but there is some indication leakage is more likely at low temperatures. It is possible leakage is due to movement of the O-ring during temperature or pressure cycling at the beginning or end of a test. The radiotracer method involves less labor and is much less susceptible to contamination than the previous method. Future work will investigate leakage past lubricated O-rings and time dependence of leakage. 1 reference, 1 table.
This paper reviews different helium-cooled first wall and blanket designs; and compares the selection of structural materials. The authors found that the solid breeder, SiC-composite material option generates the lowest amount of induced radioactivity and afterheat and has the highest temperature capability. When combined with the direct cycle gas turbine system, it has the potential to be the most economical fusion system and can compete with advanced fission reactors. When compared to martensitic steel and V-alloy, SiC-composite is the least developed of these three structural materials, a focused development effort will be needed. Fundamental research has begun in addressing the issues of optimized composite materials, irradiation effects, leak tightness and low activation braze materials. Development of helium-cooled high heat flux components and further development of the direct cycle gas turbine system will also be needed.
In many drug dispensing devices, such as syringes and inhalers, an elatomeric gasket is used to prevent the formulation from leaking from the chamber. During device actuation, the seal is subjected to friction, which in turn causes its deformation and can cause unintentional leakage, thus dose variability. Additionally, friction of seal is responsible for a host of potential problems such undue effort required for actuation and potential wear. The mechanism of friction generation in the seal conjunction is complex, arising from adhesion of rubber in contact with the moving interface, viscous action of a thin film of fluid and deformation of seal asperities. Therefore, the first step in understanding the conjunctional behaviour of rubber seals is a fundamental study of mechanisms of frictio...
Material degradation of pressure tubes, which are the most important components in CANDU fuel channel, can only be evaluated by removing and examining them(material surveillance). This study aimed at establishment of overall evaluation technology including the evaluation of the material degradation for the integrity of pressure tubes of Wolsung units. Material tests for pressure tubes were performed as follows; (1) Evaluation on life limiting factors of pressure tubes (2) Review on leak-before-break and integrity maintenance technology of pressure tubes (3) Survey on selection criteria for tubes to be inspected and on related regulations for material surveillance (4) Analysis of material surveillance test procedure (5) Basic examinations of Wolsung unit 1 pressure tube material(TEM, texture, chemical component etc) (6) Manufacture of test equipments and test (DHCV, hydriding, grip and tensile specimen etc). 23 figs, 6 tabs, 59 refs. (Author).
The presence of an extraneous light gas must be taken into account in consideration of centrifugal separation of uranium isotopes, when there is inevitable leakage of such a gas through the gas sealant and/or leaking in from the atmosphere. Consideration is first given to the influence of the presence of the light gas on the maximum separative power. Then the basic equation for isotope separation containing a light gas is derived from Hirschfelder's diffusion equations. This equation is solved and the separative performance is expressed in terms of the shape factor and reflux parameter. The formulas for expressing the flow configurations of the gases are obtained for a simple model in which inflow and outflow prevail throughout the centrifuge. The corresponding equation for a model in which the gases flow in two concentric thin streams is also derived. It is concluded that the influence provided by the presence of a light gas is quite significant if the gas ...
The Fast Flux Test Facility (FFTF) is a 400 MW(th) sodium cooled reactor and is the largest test reactor of its type in the world. It was designed and is being operated to serve two purposes: gaining liquid metal system experience and serving as a test bed for fuels and materials. During test operations it is possible that cladding breaches and escape of fission gas to the reactor cover gas region can occur. To identify the source of such a leak all 78 fuel pin assemblies contain ''gas tag'' with a unique ''tag'' mixture in each assembly. The mass spectrometric identification of tag isotope ratios makes possible rapid location and thus faster removal (if required) of breached test pins.
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 ...
The nature and relationship of methane to coal mines is discussed and sources of information are outlined. Methods of gas analysis in general and methods for the detection of methane in use in coal mines are described. Methods of remote detection of gases and those that have application for use in underground coal mining operations are discussed. The report represents recommendations on remote methane detection systems that may find application in underground coal mines. (20 refs.)
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.
Samples of fat coal-E, its roof sandstone-A and blind coal-W from two coal mines in Hebei Province of China were brought to the laboratory to study the features of infrared thermal images and radiation temperature in the course of uni-axial load and uni-axial cycle load. To check the results of infrared remote sensing detection, two other methods, acoustic emission detection and electrical resistance detection were also used. The AGA-782 thermalvision detected change of the temperature field of the samples` surfaces. The study showed that: (1) coal rocks and sandstone in the course of loading have three types of infrared thermal image features and three types of infrared radiation temperature features; (2) infrared detection is comparable with acoustic emission detection and electrical resistance detection. Generally, the infrared ...
{sup 60}Co is produced as an activation product and is present in the low-level aqueous radioactive waste released from the La Hague plant. At present, the concentration in the sea (non filtered at 0.45 {mu}m) at the Goury site are close to or even below, the detection limit: 0.2 mBq.l{sup -1}. The {sup 60}Co speciation depends on the type of effluent considered: in the effluent A ('active'), the cobalt is in the form of a stable trivalent complex; in the effluent V (to be checked), the cobalt is in majority (50% of the activity release) in the form of particles (>0.45 {mu}m), and then in the form of two soluble species: ionic divalent (Co{sup 2+}) and some stable complexes. The evolution of the reprocessing techniques used does not affect the speciation. So, since the nuclear reprocessing plant started at the La Hague plant in 1966, the chemical species discharged in the sea shows time variation related to the evolution of the type of ...
The paper present the results of the study on D.U. (depleted uranium) contamination in the environment and possible effects on animal healths in the region o f Bujanovac. Samples of soil, feed, leaves, grass, lichen, moss, honey and water were collected randomly in 2003/2004 in the vicinity of the target area (500-1000 m) and 5 km from the target area. Activity of the radionuclides ({sup 226}Ra, {sup 232}Th, {sup 40}K, {sup 210}Pb, {sup 238}U, {sup 235}U, {sup 137}Cs, {sup 7}Be) in soils, grass, lichen, moss and honey was determined on Hp Ge detector (Canberra, relative efficiency 23%) by standard gamma spectrometry. Total alpha and beta activity in water was determined on proportional alpha/beta counter (Canberra 2400, efficiency for alpha emitters 11%, efficiency for beta emitters 30%). Non significantly higher values of concentrations of {sup 226}Ra, {sup 232}Th, {sup 238}U and {sup 235}U were measured in the immediate vicinity of the ...
Environmental monitoring data were collected at and around the Area 3 and Area 5 Radioactive Waste Management Sites (RWMSs) at the Nevada Test Site. These data are associated with radiation exposure, air, groundwater, meteorology, vadose zone, subsidence, and biota. This report summarizes the 2006 environmental data to provide an overall evaluation of RWMS performance and to support environmental compliance and performance assessment (PA) activities. Some of these data (e.g., radiation exposure, air, and groundwater) are presented in other reports (U.S. Department of Energy, 2006; Warren and Grossman, 2007; National Security Technologies, LLC, 2007). Direct radiation monitoring data indicate that exposure levels around the RWMSs are at or below background levels. Air monitoring data at the Area 3 and Area 5 RWMSs indicate that tritium concentrations are slightly above background levels. There is no detectable man-made radioactivity by gamma spectroscopy, and ...
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 ...
The Institute of Energetic and Nuclear Research - IPEN is a research and development institution, located in a densely populated area, in the city of Sao Paulo. The nuclear fuel cycle was developed from the Yellow Cake to the enrichment and reconversion at IPEN. After this phase, all the technology was transferred to private enterprises and to the Brazilian Navy (CTM/SP). Some plants of the fuel cycle were at semi-industrial level, with a production over 20 kg/h. As a research institute, IPEN accomplished its function of the fuel cycle, developing and transferring technology. With the necessity of space for the implementation of new projects, the uranium hexafluoride (UF{sub 6}) production plant was chosen, since it had been idle for many years and presented potential leaking risks, which could cause environmental aggression and serious accidents. This plant decommission required accurate planning, as this work had not been carried out in Brazil before, for this ...
During the Bruce A Nuclear Generating Station (BNGS-A) Unit 1 1997 planned outage, a dew point search method identified a leak in one steam generator(SG) tube. Subsequently, the tube was inspected with all available eddy current probes and removed for examination. The initial inspection results and metallurgical examination of the removed tube confirmed that the leak was due to intergranular attack/stress corrosion cracking (IGA/SCC) emanating from the secondary side of the tube at the top of the tubesheet location. Subsequently, eddy current and ultrasonic indications were found at the top of the tubesheet of other Alloy 600 SG tubes. To investigate the source of the indications and to validate the inspection probes, sections of 40 tubes with various levels of damage were removed. The metallurgical examination of the removed sections showed that both secondary side and primary side initiated, circumferential, stress corrosion cracking and ...
Since the integrity of the containment penetrations was confirmed under accident management (AM) conditions in the former test, failure criteria tests and aerosol trapping tests were carried out using low-voltage modules and flange gaskets of an actual plant under severe accident (SA) conditions, without AM. The safety margin for failure temperature of the penetrations and the credit for fission product (FP) aerosol trapping effect along the leakage paths of the degraded penetrations were evaluated in the present tests. Failure temperature of the penetrations ranged from 270 to 300degC for low-voltage modules and 300 to 350degC for flange gaskets under 0.4 to 1.0 MPa conditions. Pressure dependency on failure temperature was small. This means that the safety margin of failure temperature under AM condition is more than 70degC. By introducing a equivalent leak area for the damaged test pieces, total leak area was estimated which was smaller than ...
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 ...
Aim: Compounds such "9"9"mTc-MDP and "9"9"mTc-HEDP are used regularly in bone scintigraphy for metastasis detection. The therapeutics properties of beta emitter radionuclides like "1"5"3Sm, "1"6"6Ho and "1"7"7Lu has been widely reported in literature being "1"7"7Lu the less developed for medical applications. With the purpose of study different radiopharmaceuticals alternatives, for metastasis bone palliation, we have evaluated, on a comparative basis, the labeling of "1"5"3Sm-MDP, "1"5"3Sm-HEDP, "1"6"6Ho-MDP, "1"6"6Ho-HEDP, "1"7"7Lu-MDP and "1"7"7Lu-HEDP from the exhibited radionuclidic purity and biological distribution point of view. Material and Methods: The radionuclides were produced at La Reina Research Reactor, Chilean Nuclear Energy Commission. The radionuclidic purity was determined by gamma-Ray spectrometry. The labeling was accomplished with MDP (Plenum) and HEDP synthesized in-house. The in-vitro affinity of labeled compounds to the mineral bone matrix ...
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 ...
A new surveillance system for Oil-Filled cable, which can provide continuous monitoring, using a newly developed optical gas sensor that can detect the concentration of the gas dissolved in the oil with extremely high sensitivity has been developed. It was proved that the degree of deterioration of the insulating oil can be detected by measuring C{sub 2}H{sub 2} and CH{sub 4} by investigating the relation between the degree of deterioration and amount of combustible gas generated. In order to detect extremely small amounts of gas, a new gas detecting method using absorption line of the gas using a frequency modulated technique has been developed. The gas detection ability was also confirmed by examination using a 66 kV of cable and the possibility of detection at an early stage is expected.
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)
This Waste Management Plant (WMP) for the Bear Creek Valley Treatability Study addresses waste management requirements for the Oak Ridge Y-12 Plant. The study is intended to produce treatment performance data required to design a treatment system for contaminated groundwater. The treatability study will consist of an evaluation of various treatment media including: continuous column tests, with up to six columns being employed to evaluate the performance of different media in the treatment of groundwater; an evaluation of the denitrifying capacity and metal uptake capacity of a wetland system; and the long-term denitrifying capacity and metal uptake capacity of algal mats. The Sampling and Analysis Plan (SAP) covers the project description, technical objectives, procedures, and planned work activities in greater detail. The Health and Safety Plan (HASP) addresses the health and safety concerns and requirements for the proposed sampling activities. This WMP identifies the types and ...
Aqueous deoxyhemoglobin solutions (2 mg/ml) were gamma-irradiated by a "6"0Co source in the presence of methanol, ethanol, 1-butanol and t-butanol under N_2O or argon. The effects of the interaction of the particular alcohol radical species with hemoglobin were determined according to the detected spectral alterations in the visible range. The amounts of stable final products in the form of methemoglobin (MetHb) and the sum of hemichromes and cholehemichromes (Hemichr) were estimated in irradiated preparations. For preparations irradiated under N_2O, the radiation yield for MetHb formation was three-fold lower in the presence of ethanol and 1-butanol [G(MetHb) = 0.33[ compared with preparations irradiated in the presence of t-butanol or without alcohol [G(MetHb) = 1.00[. The yield of hemichromes and cholehemichromes in preparations irradiated under N_2O increased in the order: ethanol (G = 0.38), 1-butanol (B = 0.52), t-butanol (G = 0.59), and in the absence of ...
Due to the large number of chemicals in commerce without adequate toxicity characterization data, coupled with an ineffective federal policy for chemical management in the United States, many states are grappling with the challenge to identify toxic chemicals that may pose a risk to human health and the environment. Specific populations (e.g., children, elderly) are particularly sensitive to these toxic chemicals. In 2008, the Children's Safe Product Act (CSPA) was passed in Washington State. The CSPA included specific requirements to identify High Priority Chemicals (HPCs) and Chemicals of High Concern to Children (CHCCs). To implement this legislation, a methodology was developed to identify HPCs from authoritative scientific and regulatory sources on the basis of toxicity criteria. Another set of chemicals of concern was then identified from authoritative sources, based on their potential exposure to children. Exposure potential was evaluated by identifying chemicals ...
Japan Atomic Energy Research Institute (JAERI) and High Energy Accelerator Research Organization (KEK) are promoting construction plan of Material-Life Science Facility, which is consisted of Muon Science Facility and Neutron Scattering Facility, in order to open up the new science fields. The Neutron Scattering Facility will be utilized for advanced fields of Material and Life science using high intensity neutrons generated by the spallation reaction induced by injecting a 1 MW pulsed proton beam onto a mercury target. Design of the spallation mercury target system is in progress to obtain good neutron performance keeping high reliability and safety. The target material is mercury. As a result of the spallation reaction, large amount of radioactive spallation products are to be contained in the mercury. Therefore to establish the safety of the target system, transient behaviors of the system during anticipated events should be well understood. The safety protection system and an ...
In association with excavation of the No. 135 steam producing well in the Onikubi geothermal power plant in Miyagi Prefecture, shapes of production zones and drilling-induced fracture (DIF) were acquired from the borehole televiewer (BHTV) data. The BHTV logging shoots sound waves onto well walls of wells filled with fluid and detects the reflection waves to investigate the state of the well walls. Vertical fracture with opening lengths from 2 to 3 m were found at depths of about 1232 m and 1312 m. Water run-off has occurred at a depth of about 1312 m during the excavation, to which these vertical fractures might have contributed possibly. In depths of about 1232 m and 1312 m, fractures inclining toward north-east direction and south-west direction are predominant. Some fractures in the depth of about 1333 m incline toward east-south-east direction and west-north-west direction. Fracture inclination azimuth in all of the present logging ...
This paper describes estimation of a stress field in the earth`s crust in the Kakkonda geothermal field. Formation micro imager (FMI) logging known as a crack detecting logging was performed in the well WD-1. This FMI logging has made observation possible on cracks along well axis thought to indicate size and direction of the crust stress, and drilling-induced tensile fractures (DTF). It was verified that these DTFs are generated initially in an azimuth determined by in-situ stress (an angle up to the DTF as measured counterclockwise with due north as a starting point, expressed in {theta}) in the well`s circumferential direction. It was also confirmed that a large number of cracks incline at a certain angle to the well axis (an angle made by the well axis and the DTF, expressed in {gamma}). The DTF is a crack initially generated on well walls as a result of such tensile stresses as mud pressure and thermal stress acting on the well walls during well excavation, ...
Nuclear analytical techniques were applied to determine the elemental compositions of suspended and bottom sediments, collected at different sites in Haiphong harbor area (North Viet nam). The study was aimed at: 1/Understanding the origin of the sediment filling up the access channel and causing large expenditures for dredging operations. 2/Determining the background concentrations of trace elements in sediment. This would allow to detect in the future any pollution caused by the discharge of industrial wastes in the water due to the growing industrialization of the area. 3/Identifying the elements, which can be served as activatable tracers in sediment transport studies. The results obtained for the concentrations of nearly 30 elements show rather similar elemental compositions, reflecting a common origin of the sediments taken from different locations in the harbour area. The results could not allow to identify the pathway of the sediment ...
While underground power transmission lines have become to use CV cables as the mainstream, existing facilities still use OF cables. Factors of OF cable deterioration include heat cycles during operation and surge intrusion. As a method to diagnose this deterioration in insulation, characteristics tests are performed by collecting insulation oil in a cable connection box. The insulation oil collection work has been done conventionally with the power line stopped to prevent danger from induction voltage. A power uninterruptible oil collection tool was developed recently. The tool consists mainly of an insulator made of epoxy resin, wherein a connection box connector is rotated and loosened by operating an insulating operation rod, with the structure not contacted directly with metallic sheath, so that insulation oil can go through the oil collecting tool and gets collected. Discussions were given on the tool to be capable of collecting samples for analyzing water ...
High concentrations of Cs-137 were detected in the muscles of Walleye Pollack (Theragra chalcogramm) collected from Kitamiyamato banks (sampling on 25 Jul. 2000), Kamui area (16 Oct. 2000) and Niigata coasts (31 Jan. 2001). The concentrations were 0.35 #+-# 0.01, 0.41 #+-# 0.01, and 0.63 #+-# 0.02 Bq/kg-wet, respectively. The average concentration in our past investigations was about 0.25 #+-# 0.01 Bq/kg-wet. Samples from other areas, the coat of Kushiro (8 May 2001), North Tishima (13 Nov. 2000) and the Sea of Okhotsk (6 May 2001), had the average concentrations. There were no such high concentrations of Cs-137 in other fish species collected from Kitamiyamato banks, Kamui area, and Niigata coasts. Fish samples with high concentrations all make the migration in the north of Japan sea. These results would indicated that samples took in Cs-137 elements from sea-water or foods on the migration route. Cs-137 concentrations in muscles of walleye ...
A quantitative comparison of tissue distribution and excretion of an orally administered sublethal dose of [3H]diacetoxyscirpenol (anguidine) was made in rats and mice 90 min, 24 hr, and 7 days after treatment. Total recoveries of 95-100% were obtained. Approximately 90% of the dose was excreted in urine and feces during the first 24 hr with a feces:urine ratio of about 1:4.5 in both species. Carcass and tissue radioactivity dropped rapidly during the first 24 hr but remained relatively constant at low, but detectable, levels over the course of the experiment. Few substantive interspecies differences were noted in tissue distribution. At 90 min the highest percentage of dose was in tissues involved in sequestering diacetoxyscirpenol because of high body water/lipid content or the absorption, metabolism, or excretion of the toxin. The rank order of these tissues was generally stable over the course of the experiment. When data were expressed as ...
Acidic constituents in crude oil are associated with the formation of stable emulsions during production and present a challenge for efficient oil recovery and processing. Acid molecules, including naphthenic acids and acidic sulfur in crude oil cause corrosion in refineries and pipelines. Naphthenic acids are also significant because of their surface activity and marginal water solubility, so that they may leach to wastewaters and cause adverse environmental effects. Acidic components of oil are not limited to carboxylic acids but also molecules that contain sulfur and nitrogen. As such, an improved understanding of the chemistry and physics of petroleum at the molecular level is needed in order to understand the range of problems associated with acidic oil components and to design better solutions. The applications of negative-ion electrospray ionization (ESI) Fourier transform ion cyclotron resonance mass spectrometry (FT-ICR MS) for speciation of acidic oil ...
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 data channel: gas chromatography-mass spectrometry (GC-MS), ...
This report is a compilation of the calendar year 2003 groundwater sampling results from the Area 5 Radioactive Waste Management Site, Nevada Test Site. Wells Ue5PW-1, Ue5PW-2, and Ue5PW-3 were sampled semi-annually for the required analytes: pH, specific conductance, total organic carbon (TOC), total organic halides (TOX), tritium, and major cations/anions. Results from all samples collected in 2003 were within established criteria. These data indicate that there has been no measurable impact to the uppermost aquifer from the Resource Conservation and Recovery Act (RCRA) regulated unit within the Area 5 Radioactive Waste Management Site and confirm that any previous detections of TOC and TOX were false positives. Contamination indicator data are presented in control chart and tabular form with investigation levels indicated. Gross water chemistry data are presented in graphical and tabular form. There were no major changes noted in the ...
...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.
BackgroundEpilepsy is a common neurological disorder characterized by recurrent electrophysiological activities, known as seizures. Without the appropriate detection strategies,...Full Text Available
A commercially available synthetic nucleic acid probe (SNAP) conjugated to alkaline phosphatase was compared with standard culture techniques for detecting Campylobacter species. The SNAP was able to...Full Text Available
This paper discusses the possible detection of magnetic monopoles and monopole tachyons. Topics considered include insects, astrophysics, general relativity theory, plants, and biotechnology. The paper was presented at an international symposium on non-conventional energy technology.
To understand the function of edges in perception of moving objects, we defined four questions to answer. Is the focus point in visual motion detection of a moving object: (1) the body or the edge of...Full Text Available
Dental caries continues to be a common chronic disease among various population groups. Patient care can be improved with detection at the earliest stage. However, current techniques do not...Full Text Available
PurposeSatisfaction of search (SOS) occurs when an abnormality is missed because another abnormality has been detected. This research studied whether the severity...Full Text Available
A rapid, sensitive, and simple method was developed to detect the sapstain fungi Ophiostoma piceae and O. quercus in stained wood. By using microwave heating for DNA...Full Text Available
We have evaluated the performance of two rapid, low-cost methods for the detection of ofloxacin (OFX) resistance with 95 Mycobacterium tuberculosis isolates from countries with high...Full Text Available
Data on a technique for the detection of antigen from arthropod vectors in a dot immunobinding assay are presented. In this system, antigen present in the vector was first solubilized in sodium dodecyl...Full Text Available
Randomly amplified polymorphic DNA (RAPD) analysis and the PCR assay were used in combination with dilution plating on a semiselective medium to detect and enumerate propagules of Trichoderma...Full Text Available
... detected (and reported) as a by-product of MRM screening (MS/MS) targeted by Law or Rule ... detected (and reported) as a by-product of MRM screening (MS/MS) targeted by Law or Rule ...
A latex agglutination (LA) test was evaluated for the detection of human rotaviruses in stool specimens. Both antiserum and immunoglobulin G (IgG)-sensitized latex particles were used, with IgG-coated...Full Text Available
A real-time immunoquantitative PCR (iqPCR) method for detection of Staphylococcus aureus enterotoxin B (SEB) was developed and evaluated using both pure cultures and foods. The assay...Full Text Available
PurposeThe aim of this investigation was to exploit lens-specific glycated crystallins as an immunogen to detect human glycated crystallins and their circulating autoantibodies in...Full Text Available
SynopsisEarly detection of late onset neonatal sepsis, prior to obvious and potentially catastrophic clinical signs, is an important goal in neonatal medicine. Sepsis causes a...Full Text Available
With the advent of dense maps of human genetic variation, it is now possible to detect positive natural selection across the human genome. Here we report an analysis of over 3 million polymorphisms...Full Text Available
The genetic systems of bacteria that have the ability to use organic pollutants as carbon and energy sources can be adapted to create bacterial biosensors for the detection of industrial pollution....Full Text Available
OBJECTIVE: To evaluate the commercial microparticle enzyme immunoassay (MEIA), Abbott IMx Select Chlamydia, for the detection of Chlamydia trachomatis in women and to compare its performance with endocervical...Full Text Available
We compared MRSA Select to mannitol-salt agar with 8 μg/ml cefoxitin for the detection of methicillin-resistant Staphylococcus aureus (MRSA) from 6,199 clinical...Full Text Available
The aim of this study was to evaluate a nitrate reductase assay (NRA) performed on smear-positive sputa for the direct detection of rifampin resistance in Mycobacterium tuberculosis....Full Text Available
The direct detection of pyrazinamide resistance in Mycobacterium tuberculosis is sufficiently difficult that many laboratories do not attempt it. Most pyrazinamide resistance is caused...Full Text Available
Endocervical swabs from 212 women and urethral swabs from 100 men were tested by the routine methods for McCoy cell culture and simultaneously by a novel enzyme amplified immunoassay test to detect...Full Text Available
We have discovered interstellar rubidium by observing the resonance line of Rb I at 7800 A toward zeta Oph. This is the heaviest element yet detected within the interstellar medium, and our detection of this element is important for understanding the history of nucleosynthesis in the solar neighborhood.
Objectives. We investigated increases in diarrheal illness detected through syndromic surveillance after a power outage in New York City on August 14, 2003.Methods....Full Text Available
A serodiagnostic test has been developed for the detection of Plasmodium falciparum in infected blood. Using parasite antigens and infected red blood cells from in vitro...Full Text Available
A serological trapping technique for detecting rotaviruses is described which involves coating electron microscope grids with protein A and specific rotavirus antiserum. The presence of a layer of antibodies...Full Text Available
The dielectrophoretic (DEP) crossover method has been applied to the detection of cell responses to toxicants. Time and dose responses of the human cultured leukemia (HL-60) line were measured...Full Text Available
PCR was used with the primer pair VANS1-NS21 to detect the arbuscular mycorrhizal fungus Glomus intraradices (commercial inoculum source) on roots of lettuce, zinnia, leek, pepper, and endive plants....Full Text Available
A sensitive assay based on the polymerase chain reaction for the detection of Ockelbo virus RNA was developed. Two primer pairs from the gene coding for the E2 glycoprotein were chosen. By use of a...Full Text Available
Colonies of toxin-producing Pasteurella multocida were detected with peroxidase-labeled monoclonal antibodies by a membrane assay. Examination of the specificity of the assay with 29 P. multocida cultures...Full Text Available
Since bearing is in wide use as basic parts for rotary machines, detection and diagnosis of its defects are important in practical use. To discriminate defect portions by early detection of roller bearing flaking, the conventional parameter method using peakedness is poor. Thus to directly obtain difference in waveform, the new method was applied to such detection which uses KDI as the scale of a difference in waveform, and a most neighborhood classification rule based on KDI. The detection and discrimination abilities of this method was studied mainly in experiment. The experiment used a bench scale rotor and a supporting bearing, and attempted detection and discrimination of no flaking, outer ring flaking and inner ring flaking. As a result, this method could detect and discriminate fine flaking which was never detected by conventional ...
Real-time PCR has the potential to streamline detection and identification of Cryptosporidium spp. in human clinical samples. In the present...Full Text Available
A nonmammalian test system for germ-cell mutagenesis has been developed by using the Japanese medaka fish. We describe a system for detecting DNA alterations in F1 progeny descended from the gamma-irradiated...Full Text Available
Background/AimsThe findings of several recent studies suggest that antinuclear antibodies (ANAs) are frequently detected in patients with acute hepatitis A (AHA). However, the clinical...Full Text Available
In this paper the authors prove a uniqueness theorem for the electric detection of cavities in a three dimensional solid from Cauchy data measured on the surface. The cavities, finite in number, are assumed to be insulating. The surfaces of the cavities are assumed to be smooth on the complement of a set that is, in some sense, negligible. (orig.)
Discrete masses are commonly detected during mammographic screening and most such lesions are benign. For lesions without pathognomonically benign imaging features that are still regarded likely to...Full Text Available
We prepared polyclonal antibody specific to Mycoplasma pneumoniae and examined the conditions influencing the ability of an indirect immunofluorescence test to detect the specific antigen in respiratory...Full Text Available
A sensitive and specific detection method was developed for Xanthomonas hyacinthi; this method was based on amplification of a subsequence of the type IV fimbrial-subunit gene fimA...Full Text Available
There is no gold standard diagnostic test for the detection of bovine cryptosporidiosis. Infection is usually highest in 2-week-old calves, and these calves also excrete high numbers of oocysts. These...Full Text Available
BackgroundThe commonest pathogenic DMD changes are intragenic deletions/duplications which make up to 78% of all cases and point mutations (roughly 20%) detectable...Full Text Available
We proposed a faster pedigree-based generalized multifactor dimensionality reduction algorithm, called PedG-MDR II (PII), to detect gene-gene interactions underlying complex traits. Inherited...Full Text Available
A duplex TaqMan real-time RT-PCR assay was developed for the detection of California (CAL) serogroup viruses and Cache Valley virus (CVV), for use in human surveillance. The targets selected...Full Text Available
Synthetic complementary oligonucleotides are useful hybridization probes for the detection of mRNAs and genes encoding proteins for which only a partial amino acid sequence is known. Usually this involves...Full Text Available
number Fax (501) 228-3600 (501) 228-3601 Surface Water Data Information Requests Bill Baldwin (501) 228-3602 Surface Water General Information Jaysson Funkhouser (501) 228-3663...
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
In order to reduce the air concentration of (sup 3)H in the reactor buiIding of Wolsung Heavy Water Reactor, a computer code for estimation of adsorption behavior was programmed based on an equation derived for analysis of water vapor adsorption, and a ba...
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
By the time of primary 21st century, water hyacinth had become a serious environmental problem in China. Water hyacinth contributes to the major part of ecological hazards from the invasion of foreign...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
average bulk water temper ature rise, OF bulk water temperature at elevation z, OF bulk water temperature in channels 0 and 1, O F film temperature, OF ...
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
The design and material characteristics of garter spring were summarized and Nondestructive detection techniques of garter spring were also described. In particular, Eddy current testing of loose type garter spring was used in Wolsung unit 1 and was described in detail. The inspection technique of tight type garter spring has not been established and all candidated techniques were investigated in order to choose the possible detection technique. Candidated nondestructive techniques including RFEC, PEC, Magnetic technique using GMR sensor, AE, Guided Wave technique, and high frequency ultrasonic technique, are summarized for evaluating the detectability of tight garter spring.
Sep 16, 2010 ... Taking military operations as an example, there is evidence that stress-related behavioral disorders and mental conditions such as anxiety, ...
Thermal neutron beam from the TNRF of JRR-3M was utilized for detection of mice lung cancer in vivo. Both the static and real-time neutron imaging were tried. Very strong thermal neutron beam is necessary to detect lung cancers because small changes are hidden by the very large attenuation of thermal neutron beam by the hydrogens in the tissues. The detection was successfully performed. Especially, the Super Eye of Hamamatsu Photonics contributed very effectively. Bone marrows and cartilages were also shown clearly. If an efficient and compact neutron source will become available in future, this method will grow up as a powerful tool for biomedical application. (author).
This invention relates to new phosphor materials and to combinatorial methods of synthesizing and detecting the same. In addition, methods of using phosphors to generate luminescence are also disclosed.
THMs are disinfection by-products (DBPs) generated during water chlorination. Concentration of individual and total THMs, depends on treatment process and THMs precursors level. ATLL water utility has two DWTP (Llobregar and Ter) that produce and supply drinking water to Barcelona and regional area. This work studies the levels of THMs along the ATLL distribution system (450 km). Although, no differences were observed along water pipes system, changes of water resource and mix procedures were related. (Author) 12 refs.
In a supercritical water-cooled reactor, property of water changes significantly around the critical point. It is expected that irradiation and change of water property will affect the chemistry and material corrosion. Deep understanding of interactions between supercritical water and materials under irradiation is important. However, comprehensive data on radiolysis, kinetics, corrosion and thermodynamics have not been obtained due to the severe experimental condition. To get such data by experiments and computer simulations, a national program funded by Ministry of Education, Culture, Sports, Science and Technology (MEXT) has been started since December 2002. (author)
In this paper the diffusion of tritiated water vapor into concrete walls is studied to evaluate tritiated water retention 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 water retention 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, we first discuss the detection of supernova neutrino on Earth. Then we propose a possible method to acquire information about $\\theta_{13}$ smaller than $1.5^\\circ$ by detecting the ratio of the event numbers of different flavor supernova neutrinos. Such an sensitivity cannot yet be achieved by the Daya Bay reactor neutrino experiment.
The neutron detector is cased in a metal envelop and has one detector with a very sensitive fission chamber and a second detector with a fission chamber less sensitive that the first one and a boron coated ionisation chamber for reducing gamma radiation detection.
A method is provided for detecting pathological macromolecules in a patient. The method is comprised of the following: obtaining body fluid from the patient; pretreating the body fluid; subjecting the pretreated body fluid to size-exclusion chromatography to create an excluded fluid; and analyzing the excluded fluid to detect macromolecules having a predetermined molecular weight. The method also allows for comparing elution spectra with reference spectra of suspect pathologic proteins.
The indirect detection of particle dark matter (DM) is based on the search for anomalous components in cosmic rays (CRs) due to the annihilation of DM pairs in the galactic halo, on the top of the standard astrophysical production. These additional exotic components are potentially detectable at Earth as spectral distortions for the various cosmic radiations: $\\chi + \\chi \\to q \\bar{q}, W^+ W^-, ... \\to \\bar{p}, \\bar{D}, e^+ \\gamma and \
ORNL has developed the technology to detect hidden explosives in luggage using X ray and neutron detection devices. The Federal Aviation Administration has ordered the airlines to buy and install Thermal Neutron Analysis (TNA) units. The combined pulsed-neutron and X-ray interrogation inspection (CPNX) system developed at ORNL uses less radioactive materials as well as being more sensitive to weapons, electronic devices and plastic explosives.
We sequenced 16S rRNA genes from the vaginal swab contents of a postmenopausal woman with asymptomatic bacterial vaginosis (BV). Sequences from Atopobium vaginae were the most commonly detected. In a survey of 35 other postmenopausal women, this organism was detected in 44% with BV but not in any subjects deemed healthy. PMID:15071062
Surveillance of a population, such as a weapon stockpile, is needed to discover manufacturing defects as well as deterioration as the population ages. This article considers the risks of sampling rates for surveillance from three perspectives: detection probability of defects in a proportion of a population with pass/fail data, detection of a trend in a defective proportion of the population with pass/fail data, and detection of a trend with quantitative degradation measurements. Understanding of these risks will help the decision maker choose a sampling rate to protect against such problems of a specified size at a tolerable risk.
Ground water is treated in the Czech Republic so that small water tanks are built above each water source to serve the primary ground water treatment; water so pretreated is then concentrated in large basins for subsequent treatment. Some water tanks where the first contact of the ground water with air takes place were selected as sites predisposed to radon accumulation. The examination was carried out near the town of Jihlava, where the bedrock contains slightly elevated radium concentrations. The average radon concentrations lay within the region of 2-4 kBq/m"3; the instantaneous values, however, exhibited appreciable periodical variations during the day. The relatively high radon concentrations will not pose a marked hazard for the personnel because the employees only reside at the sites in question for 10 to 15 minutes within 2 days, not ...
... Marine transport and oil disposal by boats and Matadi pose threats in the region. When the water ... Marine transport and oil disposal by boats and Matadi pose threats in the region. When the water ... ...
Using air as a carrier gas is common in humidification?dehumidification desalination processes. A computer program was written using mass and energy balances for modeling the process behavior. The parameters considered in this work were inlet air and fresh water recycle temperatures, inlet air flow rate, saline water and fresh water recycle flow rates, and saline water to air flow ratio. Results of simulation showed that increasing inlet air and fresh water recycle flow rate increases fresh water production. It was also found that heating the inlet air to humidification column or cooling the inlet water to dehumidification column increases the production rate but increasing water to air flow ratio in a humidifier leads to a lower production rate. The predicted effects of the parameters on ...
ObjectiveTo evaluate the effect of moderate aerobic physical activity in water on fetal cardiotocography patterns in sedentary pregnant women.MethodIn...Full Text Available
The very low-pressure expansion tank of the title invention is connected to the water in the central heating installation via a connecting pipe with a pump and valves on one side, and on the other side the tank is connected via a connecting pipe with valve to the tap water mains, so that the supply of water can be regulated automatically. Within the expansion tank contact with the outside air is not possible because of an air/water separating floater. By means of recording and control (also remote) of the contents of the expansion tank, the installation pressure and the quantity of supplied water from the expansion tank and the tap water mains, failures and water damage are prevented. 4 figs.