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Ing. Dr. Leopold Hufnagl 《European Journal of Forest Research》1929,51(1):20-22
Ohne Zusammenfassung 相似文献
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Ing. J. Dobrý Ph.D. Dr. A. Dziurzyński Prof. Dr. V. Rypáček 《Wood Science and Technology》1986,20(2):137-144
Summary The results of respective investigations indicate that during white rot the combustion heat of wood (Qexp (J/g)) remained virtually unchanged and at the greatest extent of decomposition it was in the range also found in non-rotten wood. During brown rot the combustion heat of wood samples increased, beginning at a weight loss of 20–30%. The difference between Qexp and the weighted mean of combustion heat values of isolated chemical wood components (Qcal) were neglectable. If Qexp values measured for each sample were taken as 100%, then Qcal averaged from 101.1–105.6% and from 97.4–108.2% during white and brown rot, respectively. The Qcal calculation error is expressed as coefficient k; it varies depending on the accuracy and selectivity of the separation methods used. 相似文献
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Carla Rohrer Bley Dr Med Vet Hans Blattmann PHD Malgorzata Roos PHD Andrea Sumova Dipl Ing Barbara Kaser-Hotz Dr Med Vet Habil 《Veterinary radiology & ultrasound》2003,44(4):470-475
Radiation treatment requires a precise procedure for interfraction repositioning of the patient. The purpose of this study was to determine the accuracy of our fixation device in treatment position and to evaluate the setup accuracy with two different methods. The positioning data of 19 canine patients with tumors in the head region (oral, nasal, cerebral) treated with photon or proton irradiation were included in this study. The patients were immobilized by means of an individualized fixation device. Focus was set upon interfraction displacement with systematic and random components. In one method, treatment position was evaluated using single plane port radiographs and megavoltage x-rays. In the other method, two orthogonal CT-topograms were acquired to evaluate the precision of positioning of the patient in the immobilization device. Systematic and random displacements were calculated and presented as mean values with corresponding 95% confidence intervals. In spite of a difference between both methods, the positioning seemed to be accurate within the expected range. It seems that a safety margin of 3.7 mm would be enough for both methods to take into account systematic and random position variability in the fixation device, thereby preventing geometric inaccuracies of treatment delivery. The reported immobilization protocol provides accurate patient immobilization for photon and conformal proton radiation therapy. 相似文献
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Ohne Zusammenfassung 相似文献
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Ing. C. Holzschuh 《Journal of pest science》1987,60(5):90-92
The species was found in Lower Austria, causing injury on about fifty trees ofPicea pungens. The introduced pest seems to be as important as in its native area of distribution, harmful especially to ornamental trees. 相似文献