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941.
This study has demonstrated that the non-contact acoustical transducer is a reasonable sensor for reflecting the road roughness profile, and the procedure is much faster in detecting the road surface roughness as compared to other measurement devices. Thus, it is a very promising sensor with regard to road roughness measurement. Furthermore, the ISO may be employed to classify the road grade. However, the assumed linearity in the PSD on a log-log graphical representation may not be true in reality, especially in the lower frequency band. Therefore, a new approach to classify road surface roughness is to be developed. 相似文献
942.
Mohamed Lamei El-Mallah 《Journal of Algebra》1983,80(2):314-322
Let A denote a prehilbert absolute valued real algebra such that (x, x, x) = 0 for all x ε A; for this algebra we obtain the same results we have previously obtained for the flexible absolute valued algebra. Our main theorem is: A has a finite dimension 1, 2, 4 or 8, and is isotopic to
or C. One of the results concerning the isomorphism between A and
, C*,
or C shows that if for every two idempotents e1 and e2 in
, then A is isomorphic to
, C*,
or C. The example of infinite dimensional Hilbert absolute valued algebra given by Urbanik and Wright indicates that the assumption, (x, x, x) = 0 for all x ε A, is essential. 相似文献
943.
The dynamics of the photofragmentation of H2S in the first continuum has been investigated at laser wavelengths 193, 222 and 248 nm. The HS fragments are produced mainly in υ = 0, as expected, but a non-negligible part of the HS radicals produced are vibrationally excited. The distribution of the vibrationally excited radicals peaks at υ = 3 or 4 at 193 nm and at υ = 2 at 222 nm. From the angular distribution of the H fragments it can be concluded that the anisotropy parameter β decreases with increasing wavelength. These results can be explained by a predissociation mechanism. Excitation in the first continuum takes place from the 1A1 ground state to the bound 1B1 state. This state is predissociated by a repulsive 1A2 state producing electronically ground-state H and HS fragments, of which the HS fragments can be vibrationally excited, resulting in a bimodal vibrational distribution. The increase of β with increasing wavelength is caused by a non-negligible lifetime in the 1B1 state. 相似文献
944.
945.
Mohga M. Eid Mohamed A. Badawy Yehia A. Ibrahim 《Journal of heterocyclic chemistry》1983,20(5):1255-1258
Benzo[h]quinoline-5,6-dione condenses with semicarbazide and its derivatives regioselectively at the 6-position and the products cyclize into the corresponding condensed 1,2,4-triazines. Reactions of the obtained triazines with a variety of reagents are described. 相似文献
946.
A method is described for the determination of 10–100 nmole of methanal and 20–150 nmole of ethanal and propanal. The method is based on the oxidation of aldehydes to the corresponding acids by mercuric ion which in turn is reduced to elemental mercury, followed by cold-vapour atomic absorption spectrometry. Calibration plots were constructed between the concentration of each aldehyde and absorbance, while the calibration from the conventional cold vapour procedure was used for total aldehydes determination. The method is selective and can be used for aldehyde determination in the presence of ketones, acetals, alcohols, acids, esters, ethers, organic chlorides and epoxides. This simple method is characterised by 98–102% recoveries and standard deviations of 3%. 相似文献
947.
Nosrat Mustafa Abed Ebtisam Abdel Aziz Hafez Nadia Sobhy Ibrahim Mohamed Elsaid Mustafa 《Monatshefte für Chemie / Chemical Monthly》1985,116(2):223-228
The behaviour of 3,5-diamino-4-phenylazopyrazole toward a variety of reagents is reported. Several new 3,5-diaminopyrazole derivatives as well as amino derivatives of fused pyrazoles have been prepared.
Untersuchungen an 3,5-Diaminopyrazol-Derivaten
Zusammenfassung Es wird über das Verhalten von 3,5-Diamino-4-phenylazopyrazol gegenüber verschiedenen Agentien berichtet. Es wurden sowohl einige neue 3,5-Diaminooyrazol-Derivate als auch einige Aminoderivate von kondensierten Pyrazolen dargestellt.相似文献
948.
Photodynamic Treatment of Rheumatoid and Inflammatory Arthritis 总被引:4,自引:0,他引:4
949.
Diacyl chlorides react with dialkylcyanamide in the presence of a Lewis acid to give amino-substituted bis-1,3,5-oxadiazinium salts in excellent yields. A mechanism leads to the formation of the product has been postulated. All new compounds have been characterized by 1H-nmr, 13C-nmr, ir-spectroscopy and elemental analysis. 相似文献
950.
Abd el Sadek el Meligy Mahmoud Ahmed el Sherbini 《Zeitschrift für Angewandte Mathematik und Physik (ZAMP)》1959,10(5):474-477
Zusammenfassung Die Absorptionsbanden der Alkalihalogenidkristalle werden auf Elektronen zurückgeführt, die an leeren Gitterstellen eingefangen sind. Als Feld wird ein bei kleinen Distanzen horizontal abgeschnittenes Coulomb-Feld angesetzt. Die Eigenwerte werden im ganzen Energiebereich aus einer genauen Reihenentwicklung der Lösungen der Schrödinger-Gleichung bestimmt. 相似文献