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971.
H.N. Özgüven 《Journal of sound and vibration》1982,85(3):383-395
This paper presents a method for the dynamic analysis of continuously and non-proportionally damped plates in bending modes. The damping can be in the form of constrained or unconstrained layers. The method is an extension of the equivalent dampers method discussed in a previous paper, in which the damping matrix of a discretized plate is replaced by a diagonal equivalent damping matrix. Each diagonal element represents an equivalent damper inserted between the structure and ground. In this method the number of equivalent dampers is reduced so that the receptance matrix of the damped structure can be obtained economically by a direct matrix method. The receptances of two different partially coated plates in transverse directions are computed by the method suggested. The verification of the results is demonstrated by comparison with the experimental values and also with the theoretical values obtained by the equivalent dampers method. The method presented can also be applied to the transverse vibration analysis of plates with discrete damping inserts. 相似文献
972.
A method is described for the determination of fluorine in iron ores, apatites and phosphate rocks, based on ion exchange on Dowex 2-X10 resin, and elution with strong hydrochloric acid. The determination is completed by a modified zirconium-eriochrome cyanine R spectrophotometric procedure. 相似文献
973.
L. Benvegnin A. Jermstad O. Östby E. Monti de Astis F. Holzbach G. Amadio L. Paronetta A. A. Perazzo A. C. Arbrecchi R. Marcille P. Jaulmes L. Ferré P. Archinard L. Espil E. Capt C. Sumuleanu G. Ghimicescu M. V. Ionescu F. Konek E. Wettstein C. Béis E. Peynaud J. Schindler K. Kozák P. Berg G. Schulze A. Heiduschka H. Sommer H. Mohler Internationales Landwirtschaftsinstitut 《Analytical and bioanalytical chemistry》1938,115(3-4):148-158
974.
Özge Yetgin Çetin Hatice Karadeniz Alper Karakaş Serpil Yenisoy-Karakaş 《Journal of Analytical Chemistry》2018,73(6):613-625
The uncertainty of measurement for well-known neurotransmitters like serotonin, noradrenalin and gamma-aminobutyric acid (GABA), glutamate and melatonin hormone with high performance liquid chromatography?fluorescence detection was calculated after the method validation. Two methods were developed for the determination of the neurotransmitters. A derivatization step was performed for the determination of GABA and glutamate. Sensitivity, method detection limit, limit of quantification, linearity, recovery, interday and intraday precision values were calculated. Low detection limit values were obtained especially for the determination of GABA and glutamate. Then, bottom-up approach was used to calculate measurement uncertainty. The critical stages of the method were evaluated. The major sources of the uncertainty budget were calibration curves, stock solution and recovery. The calculated percentage relative uncertainty values for the compounds changed between 10.1 and 16.7. 相似文献
975.
Derya Osmaniye Serkan Levent Cankız Mina Ardıç Özlem Atlı Yusuf Özkay 《Phosphorus, sulfur, and silicon and the related elements》2018,193(4):249-256
Sixteen new 2-(benzothiazol-2-ylthio)-N′-(3-substituted-4-(3,4-substitutedphenyl)thiazol-2(3H)-ylidene)acetohydrazide derivatives (4a-4p) were synthesized. The structures of the synthesized compounds were elucidated using FT-IR, 1H-NMR, 13C-NMR, and HRMS spectral data. Anticancer activity of the compounds 4a-4p against C6 (rat brain glioma) and A549 (human lung adenocarcinoma) cell lines was evaluated by using MTT, inhibition of DNA synthesis, and flow cytometric analysis assays. According to MTT assay, 4a and 4d were found to be the most active compounds against C6 cell line with an IC50 value of 0.03 mM. Moreover, IC50 values of 4a (0.2 mM) and 4d (0.1 mM) against NIH3T3 (mouse embryo fibroblast cell line) were higher than their IC50 values (0.03 mM) against C6 cell line. Accordingly, selectivity of compound 4a against C6 cell line was two-fold higher than that of compound 4d. Flow cytometry analysis showed that these compounds display anticancer activity by inducing apoptosis. As a result, compound 4a has a remarkable anticancer activity and a good selectivity towards C6 cell lines. 相似文献
976.
Cemil Ibis Sibel Sahinler Ayla Şenol Yavuz Hatice Asar Funda Özkök Hakan Bahar 《Phosphorus, sulfur, and silicon and the related elements》2018,193(6):358-362
In this study, S-, S,S- and S,O-substituted novel nitrodiene compounds were synthesized. Cyclization products were formed when difunctional nucleophiles were used. The stereoisomerism of a heterocyclic nitrodiene is discussed with the help of XRD studies. The structures of all compounds were characterized by spectroscopic methods (FT-IR, 1H NMR, 13C NMR, 19F NMR, MS) and microanalysis. 相似文献
977.
Low-cost pistachio shells were used for the production of small pore carbon molecular sieves by the benzene deposition method. The prepared materials were characterized by the Brunauer–Emmett–Teller surface area and scanning electron microscopy. The deposition temperature and the deposition time parameters, which affect the formation of carbon molecular sieves, were examined. The effect of deposition temperature was examined in the range of 700–900°C, while deposition time was examined between 30 and 60?min. The optimum surface area of the carbon molecular sieve prepared by benzene deposition was 895?m2/g at 800°C. The average pore diameter of the carbon molecular sieve was 0.27?nm, principally denoted ultramicropore characteristics. The obtained values of the pore size distributions of the prepared carbon molecular sieves were in the range of 0.26–0.29?nm. 相似文献
978.
A New Table of Binary/Ternary Mixed Covering Codes 总被引:1,自引:0,他引:1
A table of upper bounds for K3,2(n1,n2;R), the minimum number of codewords in a covering code with n1 ternary coordinates, n2 binary coordinates, and covering radius R, in the range n = n1 + n2 13, R 3, is presented. Explicit constructions of codes are given to prove the new bounds and verify old bounds. These binary/ternary covering codes can be used as systems for the football pool game. The results include a new binary code with covering radius 1 proving K2(13,1) 736, and the following upper bound for the football pool problem for 9 matches: K3(9,1) 1356. 相似文献
979.
980.
Emin Özçag 《Proceedings Mathematical Sciences》1998,108(1):41-49
The existence of the neutrix convolution product of distributionx ? r Inx ? andx + ?3 is proved and some convolution products are evaluated. 相似文献