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81.
82.
The effects of nitric oxide (NO) annealing on conventional thermal oxides are reported in this letter. The oxide thickness increase, resulting from NO annealing, is found to be only a few angstroms (<0.5 nm) and independent on the initial oxide thickness. Furthermore, both the electrical and physical characteristics are improved. This technique is expected to achieve sub-5 nm high quality ultrathin dielectric films for the applications in EEPROM's and ULSI 相似文献
83.
The resistance to slow crack growth (SCG) was measured in binary blends of high density polyethylene (HDPE) and 5–10% concentrations of model ethylene-butene random copolymers by measuring the time to failure (tf) under a constant stress intensity. An increase of tf with the addition of the copolymer if the copolymer could crystallize and the increase was greater the higher branch density. The copolymer with 117 branches/1000C could not crystallize and therefore its blend had a tf that was less than that of the HDPE. The fracture energies of the blends as determined by their resistance to SCG were compared with the energy by rapid fracture, Jc, as previously measured by Rhee and Crist. It is concluded that SCG is more sensitive to variations in the microstructure than is rapid fracture and that the differences in SCG behavior can be qualitatively explained in terms of the differences in microstructure of the blends. ©1995 John Wiley & Sons, Inc. 相似文献
84.
An analytic solution of a class of boundary-value problems of mathematical physics describing the transport of a mixture in the atmosphere is considered. To solve these problems we apply the substitution method and the Fourier method. The solution of a boundary problem describing the process of contamination of the atmosphere by various substances is presented in the form of a series. The result obtained is useful for the solution of problems concerning the protection of the atmosphere.Translated fromVychislitel'naya i Prikladnaya Matematika, No. 69, pp. 87–90, 1989. 相似文献
85.
This study introduces a method for automated analysis of the standard solid-meal gastric emptying test. The purpose was to develop a diagnostic tool to characterize more reproducibly abnormalities of solid-phase gastric emptying. The processing of gastric emptying is automated using geometrical moments that are invariant to scaling, rotation, and shift. Twenty subjects were studied. The first step was to obtain images of the stomach using a nuclear gamma camera immediately after the subject had eaten a radio-labeled meal. The second step was to process and analyze the images by a recently developed automated gastric emptying analysis (AGEA) method, which determines the gastric contour and the geometrical properties include such parameters as area, centroid, orientation, and moments of inertia. Statistical tests showed that some of the moments were sensitive to the patient's gastric status (normal versus abnormal). The difference between the normal and abnormal patients became noticeable approximately 1 h after meal ingestion. 相似文献
86.
B. Kubica M. Tuteja-Krysa Z. Szeglowski 《Journal of Radioanalytical and Nuclear Chemistry》1996,213(6):411-418
Sorption studies of Ra, Ba, Fr and Cs on nickel hexacyanoferrate(II) composite ion exchanger from hydrochloric acid and EDTA solutions are presented. 相似文献
87.
88.
Chemistry of Natural Compounds - The epigeal part ofArtemisia santolina Schrenk has yielded a new sesquiterpene lactone, artesin, C14H22O3, having the structure... 相似文献
89.
V. E. Blokhin Z. Yu. Kokoshko L. V. Kireeva E. V. Pushkareva 《Chemistry of Heterocyclic Compounds》1969,5(4):554-555
The divinyl, diallyl, and dipropargyl esters of pyridine-2,4-, pyridine-2,6-, and quinoline-2,4-dicarboxylic acids and the divinyl and dipropargyl esters of pyridine-2,5-dicarboxylic acid have been synthesized. 相似文献
90.
This preliminary study presents the experimental results concerning the concentrations of selected radionuclides (238U, 232K, 226Ra, 232Th) in Af?in-Elbistan, Çan, Çay?rhan, Erzurum, Göynük, Kangal, Orhaneli, Saray, Seyitömer, Soma, Tunçbilek, Yata?an and Yeniköy lignites, which are primarily utilized as fuel for thermal power plants in Turkey. Gamma-spectrometry of 39 representative lignite samples gave results with the following concentration ranges: 8 to 296 Bq/kg for 238U, 3 to 79 Bq/kg for 232Th, 17 to 360 Bq/kg for 40K, and 5 to 130 Bq/kg for 226Ra. The 238U results reported here are higher than other literature values for various world coals, earth's crust and world average. 相似文献