[en] Scattering functions are calculated for conditions anticipated for D-T plasmas in JET. It is concluded that scattering at millimetre wavelengths may be capable of providing useful information about the alpha particle velocity distribution function, but scattering of CO₂ laser radiation at a wavelength of 10.6 μm will not. The alpha distribution function is most easily determined when the geometry is such as to minimize the effect of the plasma magnetic field. (author). Letter-to-the-editor. 8 refs, 5 figs

[en] Dietary acid or alkali loading was given to rats by providing 150 mM NH₄Cl or 150 mM NaHCO₃ in place of drinking water for 6 days; control animals received 150 mM NaCl. After 6 days, the citrate clearance was 0.04 +/- 0.01 ml/min (mean +/- SE) in the acid-loaded group, 0.9 +/- 0.1 ml/min in the control group, and 2.5 +/- 0.2 ml/min in the alkali-loaded group. At the end of the experiment, the rats were killed, and the Na⁺ gradient-dependent citrate uptake was measured in brush border membrane (BBM) vesicles prepared from each group. At 0.3 min, the [¹⁴C]citrate uptake was 198 +/- 8 pmol/mg protein (mean +/- SE) in the acid-loaded group, 94 +/- 16 pmol/mg protein in the control group, and 94 +/- 13 pmol/mg protein in the alkali-loaded group. The rate of Na⁺-independent (NaCl in medium replaced by KCl) [¹⁴C]-citrate uptake by BBM vesicles was the same for acid-loaded, control, and alkali-loaded animals. Thus, the increased capacity of the proximal tubular BBM to transport citrate from the tubular lumen into the cell interior may be an important factor that contributes to decreased urinary citrate in the presence of metabolic acidosis induced by chronic dietary acid loading

[en] This article describes a novel programmable scaler design. It is highly adaptable and has 32 possible inputs in one unit making it a convenient and cost effective method of providing scalers for large complicated experiments. Programming and reading of the contents is performed over a VME interface. (orig.)

No abstract available

[en] This report presents the results from FY 1998 technical studies conducted by Lawrence Livermore National Laboratory (LLNL) as part of the Hydrology and Radionuclide Migration Program (HRMP) and Underground Test Area (UGTA) project. The HRMP is sponsored by Defense Programs (DP) of the U.S. Department of Energy, Nevada Operations Office (DOE/NV), and supports DP operations at the Nevada Test Site (NTS) through studies of radiochemistry and resource management related to the defense programs mission. Other participating organizations include the Los Alamos National Laboratory (LANL), the United States Geological Survey (USGS), the Desert Research Institute (DRI) of the University of Nevada, the United States Environmental Protection Agency (EPA), and Bechtel-Nevada (BN). The UGTA project is an Environmental Management (EM) activity of DOE/NV that supports a Federal Facilities Agreement and Consent Order between the Department of Energy, the Department of Defense, and the State of Nevada. UGTA's primary function is to address the legacy release of hazardous constituents at the Nevada Test Site, the Tonopah Test Range, and off-Nevada Test Site underground nuclear testing areas. Participating contractors include LLNL (Earth and Environmental Sciences Directorate, Analytical and Nuclear Chemistry Division), LANL, DRI, USGS, BN, HSI-GeoTrans, and IT Corporation. The FY 1998 HRMP and UGTA annual progress report follows the organization and contents of our FY 1997 report (Smith et al., 1998), and includes our results from CY 1997-1998 technical studies of radionuclide migration and isotope hydrology at the Nevada Test Site. During FY 1998, LLNL continued its efforts under the HRMP to pursue a technical agenda relevant to the science-based stockpile stewardship program at DOE/NV. Support to UGTA in FY 1998 included efforts to quantitatively define the radionuclide source term residual from underground nuclear weapons testing and the derivative solution, or hydrologic source term, from radionuclides dissolved in or transported by groundwater. The hydrologic source term is a component of a predicted dose assessment for the five principal NTS testing areas

[en] The in situ distribution of anthropogenic radionuclides in volcanic tuffs was measured using secondary ion mass spectrometry (SIMS). Samples were obtained from boreholes drilled in close proximity to expended underground nuclear test cavities at the Nevada Test Site, USA. SIMS measurements revealed the presence of ²²Na, ¹³⁷Cs, and enriched ²³⁵U/²³⁸U ratios. The radionuclides are distributed heterogeneously and occur at concentrations ranging from 1 to <0.1 ppm. Two processes govern the distribution of radionuclides outside the nuclear test cavity region: the prompt injection of radionuclides along fractures at the time of the nuclear detonation, and the post-test sorption of radionuclides from groundwater. A zone of prompt injection 37 m above the static water table is characterized by the correlated presence of all three radionuclides - in one case, all within a single (60 μm) point of analysis. ¹³⁷Cs is the only radionuclide detected in rocks from the saturated zone. Since these volcanic tuffs are highly zeolitized, containing up to 60 wt% clinoptilolite, it is likely that zeolite minerals control ¹³⁷Cs sorption from groundwater. However, the heterogeneous distribution of radionuclides within the zeolitized samples indicates that micro-fractures in the rock are also important in determining where the radionuclides are deposited. (orig.)

[en] Using the method of LIF we have measured with an average absolute error of 8% rate constants for rotationally inelastic collisions from level j/sub i/ = 8, 22, and 42 to level j/sub f/ = j/sub i/+Δj for Li(₂ (AΣ) colliding with Xe, Ar, and Ne. Values of Vertical BarΔjVertical Bar up to 32 were studied, involving rotational energy charges as large as 1.5 kT and collisions during which the Li₂ molecule rotated as much as 3 rad. These extremes are several times larger than the corresponding values in any previous experimental studies of rotationally inelastic collisions, and present a formidable challenge both to the experimental technique and to any general relationships used to fit the data. Four parameter fits with average deviation from the data of 11% have been found; these fits combine the energy corrected sudden approximation of DePristo et al. with our recently proposed power law-exponential expression for the basis rates k/sub j/→0

[en] The ratio of the proton's elastic electromagnetic form factors, G_Ep/G_Mp, was obtained by measuring P_t and P_ell, the transverse and longitudinal recoil proton polarization components, respectively, for the elastic (rvec e)p → e(rvec p) reaction in the four-momentum transfer squared range of 0.5 to 3.5 GeV². In the single photon exchange approximation, the ratio G_Ep/G_Mp is directly proportional to the ratio P_t/P_ell. The simultaneous measurement of P_t and P_#ell# in a polarimeter reduces systematic uncertainties. The results for the ratio G_Ep/G_Mp show a systematic decrease with increasing Q², indicating for the first time a definite difference in the distribution of charge and magnetization in the proton. The data have been reanalyzed and systematic uncertainties have become significantly smaller than previously published results