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Short course on St-02 applications of isotope dilutions and isotopic measurements

Description: This short course includes information on these topics and subtopics: (I) Nuclear Properties: (A) Historic roots; (B) Nomenclature; (C) Nuclear Stability and abundance; (D) Uses of isotopic techniques; (II) Instrumentation: (A) Sources; (B) Mass resolving elements; (C) Detectors; (III) Making Isotopic Measurements by ICP-MS: (A) Deadtime Correction; (B) Mass Discrimination; (C) Signal /Noise considerations; (IV) Applications and examples: (A) Isotope dilution; (B) Double Spike; (C) Biological Application; (D) Environmental Application; (E) Geological.
Date: January 5, 1998
Creator: Miller, P.
Partner: UNT Libraries Government Documents Department

Stable isotope applications in biomolecular structure and mechanisms. A meeting to bring together producers and users of stable-isotope-labeled compounds to assess current and future needs

Description: Knowledge of biomolecular structure is a prerequisite for understanding biomolecular function, and stable isotopes play an increasingly important role in structure determination of biological molecules. The first Conference on Stable Isotope Applications in Biomolecular Structure and Mechanisms was held in Santa Fe, New Mexico, March 27--31, 1994. More than 120 participants from 8 countries and 44 institutions reviewed significant developments, discussed the most promising applications for stable isotopes, and addressed future needs and challenges. Participants focused on applications of stable isotopes for studies of the structure and function of proteins, peptides, RNA, and DNA. Recent advances in NMR techniques neutron scattering, EPR, and vibrational spectroscopy were highlighted in addition to the production and synthesis of labeled compounds. This volume includes invited speaker and poster presentations as well as a set of reports from discussion panels that focused on the needs of the scientific community and the potential roles of private industry, the National Stable Isotope Resource, and the National High Magnetic Field Laboratory in serving those needs. This is the leading abstract. Individual papers are processed separately for the database.
Date: December 1, 1994
Creator: Trewhella, J.; Cross, T.A. & Unkefer, C.J.
Partner: UNT Libraries Government Documents Department

Autoradiographic enhancement of polaroid film. Final report, 18 April--17 October 1978

Description: SRI International has investigated the application of radiotracer photographic image enhancement (PIE) techniques to increase the photographic speed of three Polaroid Films. SRI has a state-of-the art capability in the field of nondestructive photographic image enhancement of original negatives. These procedures have successfully increased optical density, contrast, and resolution of photographic imagery, and thereby increased the information derivable from original negatives.
Date: November 1, 1978
Creator: Manning, R.G. & Pettijohn, R.R.
Partner: UNT Libraries Government Documents Department

AMS beyond 2000

Description: The occasion of this conference, the Sixth International Conference on Accelerator Mass Spectrometry, falls sixteen years after the remarkable triple simultaneous discovery of this powerful isotopic measurement. In the interval since the Fifth Conference in Paris in 1991, new facilities of both large and small size have become fully operational, achieving impressive gains in both measurement throughput and precision. The purpose of this short review is to extrapolate from recent gains and experience and to project the status of the field beyond the coming millennial date. AMS achieved instant application in archaeology and the geosciences and its early growth was stimulated by the excitement caused by the early results. The ability to obtain an accurate radiocarbon date with a sample one thousand times smaller than possible with scintillation or gas counting, the ability to trace {sup 14}CO{sub 2} in sea water with a similar thousand fold shrinkage in sample size, and the wide utility of {sup 10}Be, {sup 26}Al, {sup 36}Cl, and {sup 129}I as tracers and chronometers of erosion, hydrology and paleoclimate were sufficient to drive the partial conversion of existing accelerators and the construction of new dedicated ones. These applications remain the core of the present field and continue to justify its growth. The past few years, however, have seen developments in new fields. Biomedicine, chemical kinetics, materials science, forensic dosimetry, and arms control/counter proliferation have been explored. These applications have varying promise and will influence development of AMS programs in new ways in the future.
Date: December 28, 1993
Creator: Davis, J. C.
Partner: UNT Libraries Government Documents Department

Applications of geochemistry to problems in geothermal injection

Description: Conventional reservoir engineering studies have, in the past, dealt mainly with interpretation of pressure transient effects in a reservoir. Present-day techniques can be used in many reservoirs to forecast with some reliability the probability, magnitude and timing of pressure interference among wells. However, forecasting fluid breakthrough from an injection well to a production well in geologically complex geothermal reservoirs is not presently possible with any reliability, and forecasting thermal breakthrough is even more difficult. In addition, the chemical effects of injection are poorly understood at present, and it is not possible to predict beforehand the full range of scaling and aquifer plugging problems that may be encountered. This report discusses development of chemical tracers specifically designed for geothermal applications so that breakthrough of injectate can be detected early, and field and laboratory studies on the chemical interactions among reservoir fluids, reservoir rocks and injected fluids so that these interactions can be quantified and models developed for predicting any degradation (or enhancement) of permeability.
Date: February 1, 1985
Creator: Wright, P.M.
Partner: UNT Libraries Government Documents Department

Tracer diffusion in an ordered alloy: application of the path probability and Monte Carlo methods

Description: Tracer diffusion technique has been extensively utilized to investigate diffusion phenomena and has contributed a great deal to the understanding of the phenomena. However, except for self diffusion and impurity diffusion, the meaning of tracer diffusion is not yet satisfactorily understood. Here we try to extend the understanding to concentrated alloys. Our major interest here is directed towards understanding the physical factors which control diffusion through the comparison of results obtained by the Path Probability Method (PPM) and those by the Monte Carlo simulation method (MCSM). Both the PPM and the MCSM are basically in the same category of statistical mechanical approaches applicable to random processes. The advantage of the Path Probability method in dealing with phenomena which occur in crystalline systems has been well established. However, the approximations which are inevitably introduced to make the analytical treatment tractable, although their meaning may be well-established in equilibrium statistical mechanics, sometimes introduce unwarranted consequences the origin of which is often hard to trace. On the other hand, the MCSM which can be carried out in a parallel fashion to the PPM provides, with care, numerically exact results. Thus a side-by-side comparison can give insight into the effect of approximations in the PPM. It was found that in the pair approximation of the CVM, the distribution in the completely random state is regarded as homogeneous (without fluctuations), and hence, the fluctuation in distribution is not well represented in the PPM. These examples thus show clearly how the comparison of analytical results with carefully carried out calculations by the MCSM guides the progress of theoretical treatments and gives insights into the mechanism of diffusion.
Date: January 1, 1984
Creator: Sato, Hiroshi; Akbar, S.A. & Murch, G.E.
Partner: UNT Libraries Government Documents Department

Therapeutic radionuclides: Making the right choice

Description: Recently, there has been a resurgence of interest in nuclear medicine therapeutic procedures. Using unsealed sources for therapy is not a new concept; it has been around since the beginnings of nuclear medicine. Treatment of thyroid disorders with radioiodine is a classic example. The availability of radionuclides with suitable therapeutic properties for specific applications, as well as methods for their selective targeting to diseased tissue have, however, remained the main obstacles for therapy to assume a more widespread role in nuclear medicine. Nonetheless, a number of new techniques that have recently emerged, (e.g., tumor therapy with radiolabeled monoclonal antibodies, treatment of metastatic bone pain, etc.) appear to have provided a substantial impetus to research on production of new therapeutic radionuclides. Although there are a number of new therapeutic approaches requiring specific radionuclides, only selected broad areas will be used as examples in this article.
Date: August 1, 1996
Creator: Srivastava, S.C.
Partner: UNT Libraries Government Documents Department

Chemical tracers in Hybla Gold working room. Final report

Description: Chemical tracers were placed in the working room for the Hybla Gold event to aid in diagnosing flow of high-energy gases down expanding pipes leading from the room. If post-shot reentry is made, the tracers could provide valuable knowledge concerning pipe closure, mixing of gases from various locations, and volume of gas flow into various sizes of pipes.
Date: January 1, 1978
Creator: Killian, B.G. & McQueen, J.H.
Partner: UNT Libraries Government Documents Department

Survey of immunoassay techniques for biological analysis

Description: Immunoassay is a very specific, sensitive, and widely applicable analytical technique. Recent advances in genetic engineering have led to the development of monoclonal antibodies which further improves the specificity of immunoassays. Originally, radioisotopes were used to label the antigens and antibodies used in immunoassays. However, in the last decade, numerous types of immunoassays have been developed which utilize enzymes and fluorescent dyes as labels. Given the technical, safety, health, and disposal problems associated with using radioisotopes, immunoassays that utilize the enzyme and fluorescent labels are rapidly replacing those using radioisotope labels. These newer techniques are as sensitive, are easily automated, have stable reagents, and do not have a disposal problem. 6 refs., 1 fig., 2 tabs.
Date: October 1, 1986
Creator: Burtis, C.A.
Partner: UNT Libraries Government Documents Department

Sandia National Laboratories ASCOT (atmospheric studies in complex terrain) field experiment, September 1980

Description: During the period September 8 through September 25, 1980, Sandia National Laboratories, Division 4774, participated in a series of experiments held in the Geysers area of California. These experiments, aimed at providing data on nighttime drainage flow in complex terrain, were intended to provide a reliable basis for mathematical flow modeling. Tracers were released at several points on a valley rim and sampled by a large number of stations at ground level. Sandia's contribution was to make it possible to derive vertical tracer profiles. This was done by taking air samples from a captive balloon at chosen altitudes between the surface and 450 meters above ground.
Date: April 1, 1982
Creator: Woods, R.O.
Partner: UNT Libraries Government Documents Department

Determination of the location and connectivity of fractures in metamorphic rock with in-hole tracers

Description: In-hole tracer tests were used in a geohydrologic investigation of metamorphic rock at the Savannah River Plant near Aiken, SC to locate water-transmitting fractures and to determine the connectivity of these fractures between boreholes. Only after development of a conceptual model of the fracture occurrence and connection could the proper methods of analysis for the hydraulic parameters be selected. In-hole tracers were used to locate fractures in a borehole and supplemented other methods, such as core inspection, geophysical logs, borehole wall imaging techniques, dry drilling, and packer tests. The first three of these do not necessarily investigate fluid-transmitting fractures. In the study of the connectivity of fractures between boreholes, the in-hole tracer techniques supplemented determinations by the rapidity of hydraulic response and the use of between-well tracer tests. In hydraulically transmissive rock, fractures were located by changes in the velocity of the tracer pulse in response to adding fluid to the well. In virtually impermeable rock, the movement of the tracer pulse in the rock was normalized to the movement of another tracer pulse in the cased portion of the well because the movement was so slow that direct measurement was difficult. Connectivity of fractures between boreholes was determined by placing an in-hole tracer in one hole and measuring the movement induced by pumping a nearby borehole. From this test, it was determined that the fractures were interlacing, and single fractures did not extend from one borehole directly to the other.
Date: January 1, 1979
Creator: Marine, I.W.
Partner: UNT Libraries Government Documents Department

A tracer-based model for heat transfer in a hot dry rock reservoir

Description: A model for heat transfer in a Hot Dry Rock (HDR) geothermal reservoir is developed which predicts produced fluid thermal performance based on the tracer-determined residence time distribution and an estimated value of fracture porosity. The tracer response is modeled as flow through several paths of highly fractured rock. Fracture porosity is used to convert fluid volumes to rock volumes, which is necessary to model the heat sweep. The produced fluid response is the mixing cup average of the individual path temperatures. The model adequately represents the measured thermal response of an HDR reservoir operated at the Fenton Hill NM HDR geothermal site in the late 1970's. Application to the current Fenton Hill reservoir predicts a rapid initial thermal drawdown of about 50/sup 0/C, followed by a very slow thermal decline thereafter. The model is most sensitive to fracture porosity, and less so to the flow path geometry used to match the tracer response.
Date: January 1, 1987
Creator: Robinson, B.A. & Jones, G.F.
Partner: UNT Libraries Government Documents Department

Using chemically reactive tracers to determine temperature characteristics of geothermal reservoirs

Description: The rates of most chemical reactions are very sensitive to temperature, and this property can be used to measure temperature patterns in geothermal reservoirs. Two approaches are considered: reverse-flush and flow-through. Both of these can indicate thermal drawdown faster than the measurement of produced-fluid temperature. The reverse-flush approach is more difficult to carry out and interferes more with normal operation, but it gives the earlier indication of thermal drawdown and yields more information when using a single reaction. In both approaches, injecting a suite of reactants can yield bivariate time-temperature distributions which give temperature distributions as functions of fluid residence time. Applications to Hot Dry Rock systems are considered throughout the paper. Results of early kinetics studies of candidate tracer reactions also are reported.
Date: January 1, 1984
Creator: Robinson, B.A.; Tester, J.W. & Brown, L.F.
Partner: UNT Libraries Government Documents Department

The use of tracers to analyze the effects of reinjection into fractured geothermal reservoirs

Description: This paper discusses the use of tracers as a reservoir engineering tool in fractured geothermal reservoirs. The principle concern in injecting cooler spent fluids into a fractured reservoir is that the fluids may move through high permeability channels and return to the production wells after contacting a relatively small volume of rock. As a consequence of this rapid transport, the fluids will be only partially reheated and after a short period time will effectively mine the heat from the limited volume of rock. The production wells will then experience a rapid and premature reduction in thermal output. Tracers can be used to infer the existence of high mobility conduits between injection and production wells and to monitor chemical changes of an injected fluid. Since tracer arrival precedes thermal breakthrough, tracer tests are a very useful forecasting tool.
Date: January 1, 1987
Creator: Horne, R.N.; Johns, R.A.; Adams, M.C.; Moore, J.N. & Stiger, S.G.
Partner: UNT Libraries Government Documents Department

Tritium AMS for biomedical applications

Description: We are developing {sup 3}H-AMS to measure {sup 3}H activity of mg-sized biological samples. LLNL has already successfully applied {sup 14}C AMS to a variety of problems in the area of biomedical research. Development of {sup 3}H AMS would greatly complement these studies. The ability to perform {sup 3}H AMS measurements at sensitivities equivalent to those obtained for {sup 14}C will allow us to perform experiments using compounds that are not readily available in {sup 14}C-tagged form. A {sup 3}H capability would also allow us to perform unique double-labeling experiments in which we learn the fate, distribution, and metabolism of separate fractions of biological compounds.
Date: August 1, 1993
Creator: Roberts, M. L.; Velsko, C. & Turteltaub, K. W.
Partner: UNT Libraries Government Documents Department

Variables effecting ozone treatment of physical-chemical effluent

Description: The treatment of raw sewage from an on-site apartment area was investigated in a series of laboratory experiments in which changes in turbidity, pH, total organic carbon, chemical oxygen demand, and, in some cases, biochemical oxygen demands were determined. Raw sewage, but mainly the effluent following physical-chemical treatment, was examined for improvement in discharge quality by ozone treatment in combination with oxygen sparging, ionizing gamma radiation from /sup 60/Co heating, acidifying, and several other variables. The average composition of the raw sewage was a TOC of 125 ppM (range from 65 to 240), COD of 190 ppM (range from 85 to 475), turbidity of 145 J. U. (range from 60 to 350), and pH of 7.3 (range from 6.5 to 8.4). Physical chemical treatment usually consisted of the addition of CaO (to pH 11) and FeCl/sub 3/ as a coagulant aid in an inclined tube followed by course filtration; typical treatment time was 15 minutes giving an average reduction in TOC and COD of 40 to 60%. Subsequent treatment was usually performed with 200 cm/sup 3/ samples of the effluent in fine and course fritted bubblers. The combination of radiation plus ozone gave the largest reduction of TOC and COD. In one experiment, 15 minutes of treatment followed by 30 minutes of irradiation and ozonation reduced the raw sewage TOC from 95 to 14 ppM carbon and COD from 150 to 6 ppM oxygen. (auth)
Date: November 1, 1973
Creator: Dietz, R.N.; Pruzansky, J. & Steinberg, M.
Partner: UNT Libraries Government Documents Department

EOCR building wake effects on atmospheric diffusion. Technical memo

Description: A series of 22 simultaneous releases of three gaseous tracers was conducted around the EOCR test reactor building at the Idaho National Engineering Laboratory in SE Idaho. Hourly average gaseous tracer concentrations were sampled on several concentric sampling arcs and at a limited number of elevated locations. Winds and temperatures were measured on a nearby 30mm tower. Complete data appendices provide tracer concentration measurements, temperatures, winds and detailed wind statistics, derived diffusion statistics, and plots and analyses.
Date: January 1, 1981
Creator: Start, G.E.; Hukari, N.F.; Sagendorf, J.F.; Cate, J.H. & Dickson, C.R.
Partner: UNT Libraries Government Documents Department

Advective diffusive/dispersive transport in geochemical processes

Description: Comprehensive understanding of chemical transport in response to fluid flow and diffusion in geologic processes requires thermodynamic and transport properties of a wide variety of aqueous species at the temperature and pressure of interest, as well as mass transfer computer codes that provide simultaneously for fluid flow, diffusion, dispersion, homogeneous chemical reactions, and mineral solubilities. As a result of research carried out with support from DOE in prior years of this grant, considerable progress has been made in developing computer codes to calculate advective-dispersive-diffusional transport at both high and low pressures and temperatures. These codes have become highly sophisticated, but their application to geochemical processes is limited by the availability of thermodynamic and transport data for the major solute species in the aqueous phase. Over the past three years, research has been directed primarily toward characterizing the thermodynamic behavior of concentrated supercritical aqueous electrolyte solutions and predicting the diffusion coefficients of organic species in oil field brines. Related research has been concerned with characterizing the growth rate of hydrothermal alteration zones and assessing the relative importance of aqueous diffusion and heterogeneous reactions at mineral surfaces in geochemical processes. 103 refs., 12 figs.
Date: May 28, 1991
Creator: Helgeson, H.C.
Partner: UNT Libraries Government Documents Department

6-Acetyldihydrohomopterin and sepiapterin affect some GTP cyclohydrolase I's and not others

Description: The first enzyme in pteridine biosynthesis, GTP cyclohydrolase I, is a likely site for regulation of pteridine biosynthesis to occur. GTP cyclohydrolase I responds to hormonal treatment and is found altered in a variety of mice with genetically based neurological and immunological disorders. Genetic loci can greatly modify the activity of GTP cyclohydrolase: Punch mutant in Drosophila hph-1 in mouse and atypical phenylketonuria in human. This report examines the ability of Ahp and sepiapterin to alter the activity of GTP cyclohydrolase I from mouse liver, rat liver and Drosophila head. 20 refs., 2 tabs.
Date: January 1, 1988
Creator: Jacobson, K.B. & Manos, R.E.
Partner: UNT Libraries Government Documents Department

Analysis of five-spot tracer tests to determine reservoir layering

Description: This report presents a computer algorithm for determining the degree of heterogeneity among the layers of a reservoir. The algorithm uses the equations developed by Brigham and Smith that predict the behavior of a tracer slug flowing in a five-spot injection pattern. To illustrate the use and potential problems in the application of this algorithm, examples are presented using five sets of simulated field test data. One example using actual field data is also presented.
Date: September 1, 1978
Creator: Yuen, D.L.; Brigham, W.E. & Cinco-L, H.
Partner: UNT Libraries Government Documents Department

State-of-the-art report summarizing techniques to determine residual oil saturation and recommendations on the requirements for residual oil saturation research and development

Description: An investigation was conducted on the residual oil saturation (ROS) measurement techniques developed during the last fifteen years. Knowledge of precise ROS measurements is required for EOR project planning. The advantages, limitations, and problems of each one of the techniques are presented in tabulated form. Also, some of the possible improvements in the measurement techniques for the residual oil saturation are summarized. The following residual oil saturation techniques are discussed: core analyses, well logging, backflow tracer tests, material balance and well testing, newly developed gravity log methods, and interwell residual oil saturation measurements. Several aspects left to be improved in both instrumentations and data interpretation on pressure coring, back-flow tracer tests, well logging, material balance calculations, well testing, and interwell ROS measurements are presented. A nuclear magnetism log-inject-log method is proposed in which the need for porosity measurement for determining residual oil saturation is eliminated. 91 refs., 3 tabs.
Date: May 1, 1986
Creator: Chang, M.M. & Maerefat, N.L.
Partner: UNT Libraries Government Documents Department