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Ashed tree samples from sound and decayed Norway spruce ( (L.) H. Karst.) were studied by means of fast neutron activation analysis, and for comparison, also by X-ray fluorescence analysis. In fast neutron activation analysis, the following elements were detected: (Na), Mg, Al, Si, K, Ca, Mn, Rb, Sr and Ba, and according to the results of the X-ray fluorescence method the elements present in the wood samples were: K, Ca, Mn, Rb, Sr and Ba. A general diminishing was revealed by both methods in most elemental concentrations studied, with exception of K and Rb, when going from a sound tree to a decayed one. The use of the ratio of the amounts of potassium to calcium as an indication of the degree of decay is therefore proposed.Picea abies

Cluster deposited Pd films exhibit ferromagnetism in the temperature range from 1.8 to 400 K. The magnetization properties are found to be dependent on the film thickness. The varying morphology of the resulting Pd film with respect to thickness suggests that cluster size, deposition energy, and substrate type are crucial for the resulting film magnetization. This is demonstrated by the characteristic ferromagnetic hysteresis with the temperature dependent saturation magnetization, remanence, and coercivity of palladium nanocluster aggregates. The temperature dependence of the saturation magnetization, remanence, and coercivity of Pd nanoclusters were measured using an ultra-high-sensitive magnetometer based on a superconducting quantum interference device, and the morphology of the samples was analyzed by tunneling electron microscopy. [ABSTRACT FROM AUTHOR]

Czochralski- and float-zone- grown silicon detectors were irradiated with 2 to 5 MeV protons. Capacitance-voltage (CV) measurements served to deduce the effective doping profiles and current-voltage (IV) measurements served to obtaining information on irradiation-induced deep levels. The CV measurements show that the proton-induced net space charge is positive or negative depending on the energy of the bombarding ion. The commonly employed nonionizing energy loss hypothesis was tested with the low energy proton regime and prominent previously unobserved deviations from predictions were noted. [ABSTRACT FROM AUTHOR]

Silicon particle detectors made on Czochralski and float zone silicon materials were irradiated with 7 and 9 MeV protons at a temperature of 220 K. During the irradiations, the detectors were biased up to their operating voltage. Specific values for the fluence and flux of the irradiation were found to cause a sudden breakdown in the detectors. We studied the limits of the fluence and the flux in the breakdown as well as the behavior of the detector response function under high flux irradiations. The breakdown was shown to be an edge effect. Additionally, the buildup of an oxide charge is suggested to lead to an increased localized electric field, which in turn triggers a charge carrier multiplication. Furthermore, we studied the influences of the type of silicon material and the configuration of the detector guard rings. [ABSTRACT FROM AUTHOR]

After irradiation with 7 and 9 MeV protons, activation-induced effects were encountered in measurements of current-voltage (IV) and capacitance-voltage (CV) characteristics for Czochralski and float-zone grown silicon particle detectors prepared on printed circuit boards with copper electrodes. With the present detector construction, the 30Si(p,n)30P and 63Cu(p,n)63Zn reactions induce dominant interference in such measurements. The daughter nuclides are positron emitters with half-lives of 2.5 and 38.5 min, respectively, and the slowing down of the emitted positrons generates a significantly large concentration of electron-hole pairs in the detector volume increasing the leakage current level and decreasing the breakdown voltage. The observed time-dependent characteristics were verified by modeling the activation of the detector structure and the resulting leakage current. As a result, the electrical measurements cannot be performed immediately after irradiation due to silicon activation, and, generally, materials becoming easily activated should be avoided in the detector concept. [ABSTRACT FROM AUTHOR]

Diffusion of implanted 7Be in Si1-xGex (x=0.20,0.65,1.00) systems has been studied under intrinsic conditions in the temperature range of 460–720 °C by the modified radiotracer technique. Arrhenius-type behavior with activation enthalpies of 2.0 eV for Ge and 2.5 eV for the Si–Ge alloys was noted. Unexpectedly, the diffusivity of beryllium is higher in the Si0.80Ge0.20 material than in Si0.35Ge0.65 which is discussed in terms of possible prevailing diffusion mechanisms. It is proposed that Be diffusion in Si1-xGex systems is dissociative mechanism dominated for germanium rich materials and the kick-out (or interstitialcy) mechanism dominates in silicon rich materials. [ABSTRACT FROM AUTHOR]

The stopping powers of polycarbonate for protons of energy 0.6-5.9 MeV and α particles of energy 2.0-24.0 MeV have been measured in a transmission experiment employing thin-foil targets. The essence of the novel experimental method employed in the present measurements is to record both projectile energy and time of flight while constantly alternating measurements with and without the target foil in place. The accuracies of the proton data and α-particle data range from 2.0% to 3.0% and 2.2% to 2.7%, respectively. All of the resulting measurements were analyzed in terms of modified Bethe-Bloch theory in order to extract values of the target mean excitation energy (I) and Barkas-effect parameter (b). The composite results for the two projectiles are that I = 71.52 eV and b = 1.13, the former value lying about one standard deviation below the additivity value and the latter value lying about one standard deviation below the expected value of 1.4 ± 0.1. Previous measurements of the stopping power of polycarbonate for [sup 7]Li ions were analyzed by the same method, but with the inclusion of an effective charge parameter (δ). The proton and α-particle data, with a few lower-energy points included, were analyzed for a three-parameter fit, also. Results for the three projectiles studied indicate both internal consistency and agreement with expectations based on modified Bethe-Bloch theory. [ABSTRACT FROM AUTHOR]

Purpose: Medication-related problems and declined functional capacity are closely associated factors among older people. The purpose of this study is to describe the procedure of interprofessional medication assessment in home care context and the baseline characteristics of the study population. Methods: The FIMA study was a randomized, controlled intervention study comparing general practitioner-led interprofessional medication assessment and usual care. Patients' chronic diagnoses and medication use as well as physical and cognitive functions were investigated. Performance in daily activities, use of care services and help from family and relatives, self-rated health and health-related quality of life, and adverse effects commonly related to medication were assessed. Results: The home care patients (n = 512) had significant disease burden and functional limitations. The mean number of all medicines was 15 and that of regularly taken medicines 10. The majority of patients (87%) had excessive polypharmacy. The most commonly used (97%) ATC medicine class was nervous system medicines. Clinically relevant (class C or D SFINX record) drug–drug interactions were seen in 74% of the patients. The most frequent risks of adverse effects were risk of bleeding (66%), constipation (58%) and orthostatism (54%) occurring in over half of the patients. Medicines affecting renal function were used by 85% of the patients. Conclusions: There is an evident need and justification for medication assessments in home care. In most cases, home care patients fulfill the criteria for regular medication assessments. [ABSTRACT FROM AUTHOR]

Investigates the elastic scattering of [sup12]carbon, [sup14]nitrogen, [sup16]oxygen ions by sulfur near the non-Rutherford energy threshold below 21 megaelectronvolts. Analysis of the decreasing elastic scattering cross sections with increasing angle above a threshold energy and smooth oscillations; Function of high-enery heavy-ion beams in Rutherford backscattering spectrometry; Factors considered to predict the non-Rutherford energy threshold.

Presents a study which investigated the elastic scattering cross sections for [sup12]C, [sup14]N and [sup32]S ion bombardment below 70 megaelectronvolt at various recoil angles. Review of related literature; Brief background on elastic recoil detection spectrometry; Description of the experimental setup; Results and discussion.

Focuses on the measurement of the cross section for elastic scattering of protons through the use of natural copper (Cu), molybdenum (Mo), silver (Ag) and tin (Sn) near the Coulomb barrier. Determination of the threshold energies; Identification of those threshold energies ascertained; Experimental cross section ratios given for the elements of Cu, Mo, Ag and Sn; Information on the film thicknesses.

Studies defect formation and annealing behavior of InP implanted by low-energy 15N ions. Results of the implantation of ions into III-V compound semiconductors; Explanation of the experiment used in this study; Results of the experiment.