In the junction capacity calculation methods the passenger car unit has a very important effect, because heavy vehicle traffic flow can only be counted with passenger car unit. Since not the proper passenger car unit values are used in the current practice, the results of junction capacity calculations cannot be regarded as correct, either. This research is focused on finding an answer as to whether the results are more precise if models with three junctions are examined rather than models with one junction.
An automated device for the analysis of uranium is described. The analyser comprises a sample transfer system, a neutron counter,
a microprocessor and a teletype. A set of 100 samples, 14 ml of maximum volume, is analysed without manual intervention. The
capacity is 45 samples per hour. Using a 10 g sample the detection limit is 0.06 ppm and uranium concentrations of 1 ppm can
be determined with a precision of better than ±5%. The only source of systematic error is thorium the sensitivity of thorium
being 2.3% of that of uranium. Results for USGS standard rocks are reported and the cost of the analysis is discussed.
Authors:Gábor Skaliczki, M. Weszl, K. Schandl, T. Major, M. Kovács, J. Skaliczki, H. Redl, M. Szendrői, K. Szigeti, D. Máté, Cs Dobó-Nagy, and Zs Lacza
Purpose: The clinical demand for bone grafting materials necessitated the development of animal models. Critical size defect model has been criticized recently, mainly for its inaccuracy. Our objective was to develop a dependable animal model that would provide compromised bone healing, and would allow the investigation of bone substitutes. Methods: In the first group a critical size defect was created in the femur of adult male Wistar rats, and a non-critical defect in the remaining animals (Groups II, III and IV). The defect was left empty in group II, while in groups III and IV a spacer was interposed into the gap. Osteoblast activity was evaluated by NanoSPECT/CT imaging system. New bone formation and assessment of a union or non-union was observed by μCT and histology. Results: The interposition model proved to be highly reproducible and provided a bone defect with compromised bone healing. Significant bone regeneration processes were observed four weeks after removal of the spacer. Conclusion: Our results have shown that when early bone healing is inhibited by the physical interposition of a spacer, the regeneration process is compromised for a further 4 weeks and results in a bone defect during the time-course of the study.
A novel technique for the determination of Pt and Au at low concentrations is described. The method involves /K/ X-ray spectrometry preceded by fast neutron activation of the stable isotopes of the elements of interest. A full appraisal of the technique is presented for the analysis of small powdered samples. The sensitivity was optimized by employing a detector that was particularly effective at energies below 150 keV. The investigation formed the basis of a feasibility study which was utilized to establish if the application could be developed for the routine off-line determination of Pt and Au. We show that the method does not necessarily depend on the sample matrix, and that it proves to be a strong rival to conventional activation analysis.
This paper is meant to re-examine the relative (and, at some points, absolute) chronology of some Early Greek changes of the occlusive phonemes (i.e. devoicing of Proto-Indo-European voiced aspirates, assibilation and palatalizations) and to point out some apparent questions and problems concerning the occlusive system as a whole.
A method for simultaneous determination of uranium and thorium based on the deviation of their fission cross-section curves has been developed. Using a D-T neutron generator two different neutron spectra were produced with and without moderator around the target. The detection limits were found to be 0.044 mg and 0.25 mg in the presence of a moderator, while for fast neutrons 0.017 mg and 0.037 mg for uranium and thorium, respectively.
In the present paper the method of the equivalent differential-operator equation has been applied in the study of the existence
and asymptotic representation of periodic solutions of autonomous systems of the form