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41.
Due to the rapidly growing complexity of VLSI circuits, test methodologies based on delay testing become popular. However, most approaches cannot handle custom logic blocks which are described by logic functions rather than by circuit primitive elements. To overcome this problem, a new path delay test generation algorithm is developed for custom designs. The results using benchmark circuits and real designs prove the efficiency of the new algorithm. The new test generation algorithm can be applied to designs employing intellectual property (IP) circuits whose implementation details are either unknown or unavailable. 相似文献
42.
NMR 1H and 13C spectroscopy was successfully used to monitor the ozonation of wastewaters generated during the steaming treatment of green lumber of beech wood (Fagus sylvatica). A noticeable diminution of signals from aromatic cycle was observed. An increase of the carbonyl and carboxyl group was also noticed. The signals from the carbohydrates were constant after the ozonation. This study clearly suggest that ozonation is an effective means to degrade the phenolic compounds generated during the steam treatment.
NMR- Spektroskopie ozonisierter Abwässer von dampfbehandelter Buche (Fagus silvatica)
Zusammenfassung 1H und 13C NMR-Spektroskopie wurden erfolgreich eingesetzt, um die Ozonisierung von Abwässern, die während der Dampfbehandlung von waldfrischem Buchenschnittholz (Fagus silvatica) entstehen, zu registrieren. Eine deutlich merkbare Verminderung der Signale aromatischer Ringe wurde beobachtet. Eine Zunahme der Carbonyl- und Carboxyl-Gruppen wurde ebenfalls beobachtet. Die Signale der Kohlenhydrate waren nach der Ozonisierung konstant. Diese Untersuchung weist deutlich darauf hin, dass die Ozonisierung eine wirksame Methode zum Abbau phenolischer Komponenten darstellt, die während der Dampfbehandlung entstehen.相似文献
43.
This study implies that 55Mn(n,γ)55Mn monitor reaction may be a convenient alternative comparator for the activation method and thus, it was used for the determination of thermal neutron cross section (TNX) and the resonance integral (RI) of the reaction 152Sm(n,γ)153Sm. The samples of MnO2 and Sm2O3 diluted with Al2O3 powder were irradiated within and without a cylindrical 1 mm-Cd shield case in an isotropic neutron field obtained from the 241Am–Be neutron sources. The γ-ray spectra from the irradiated samples were measured by high resolution γ-ray spectrometry with a calibrated n-type Ge detector. The correction factors for γ-ray attenuation, thermal neutron and resonance neutron self-shielding effects and epithermal neutron spectrum shape factor (α) were taken into account in the determinations. The thermal neutron cross section for 152Sm(n,γ)153Sm reaction has been determined to be 204.8 ± 7.9 b at 0.025 eV. This result has been obtained relative to the reference thermal neutron cross section value of 13.3 ± 0.1 b for the 55Mn(n,γ)56Mn reaction. For the TNX, most of the experimental data and evaluated one in JEFF-3.1, ENDF/B-VI, JENDL 3.3 and BROND 2.0, in general, agree well with the present result. The RI value for 152Sm(n,γ)153Sm reaction has also been determined to be 3038 ± 214 b, relative to the reference value of 14.0 ± 0.3 b for the 55Mn(n,γ)56Mn monitor reaction, using a 1/E1+α epithermal neutron spectrum and assuming Cd cut-off energy of 0.55 eV. In surveying literature, the existing experimental and evaluated data for the RI values are distributed from 1715 to 3462 b. However, when the Cd cut-off energy is defined as 0.55 eV, the present RI value agrees with some previously reported RI values, 3020 ± 163 b by Simonits et al., 3141 ± 157 by Van Der Linden et al., and 2962 ± 54 b by Kafala et al., within the limits of error. 相似文献
44.
Beypazari lignite was extracted with acetonltrile and acetonitrile/HClO4 and electrochemical hydrogenation of the lignite in acetonltrile/LlC104 in the presence of HClO4. was investigated. Controlled potential electrolysis experiments were carried out at -0.5 V vs a Ag/AgCl electrode. Infrared spectra of the products were measured and yields of extraction were determined. Extraction yields In acetonitrile and acetonitrile/HCIO4 were 9 and 17.3 %, respectively. The yield of extractable material did not increased in the electrochemical environment. Acetonltrile extraction produced residual matter with less hydroxyl groups. Stirring the lignite in acetonitrile(HClO4 for 7 hours oxidized both the extract and the residue. The residue seemed to contain less hydroxyl groups than that of the acetonltrile extraction residue and It has new carbonyl and etheric groups that were absent in the original lignite. It was found that the material extracted during electrochemical treatment by acetonitrile/HClO4 was hydrogenated and the coal matrix remained intact. As the quantity of HClO4 consumed in electrolysis was increased the amount of methyl groups in the extract also increased. Higher potentials are probably neccessary to hydrogenate the coal matrix by the electrochemlcally produced hydrogen atoms. 相似文献
45.
This paper describes a dynamic model for PEM electrolyzer based on conservation of mole balance at the anode and the cathode. A further feature of the model is it includes water phenomena, electro-osmotic drag and diffusion, through the membrane. The model considers PEM electrolyzer to be composed of four ancillaries: anode, cathode, membrane and voltage ancillary. Additionally, hydrogen storage dynamics is presented. The developed model is suitable for determining control strategy that will ensure efficient and reliable operation of the electrolyzer. Moreover, the dynamic model can be integrated with renewable energy systems models to design, analyze and optimize sustainable energy systems. The study illustrates the dynamic interactions within a PEM electrolyzer and shows the necessity of the proposed approach of separate ancillaries. 相似文献
46.
Mustafa Karadag Haluk Yücel 《Nuclear instruments & methods in physics research. Section B, Beam interactions with materials and atoms》2008,266(11):2549-2555
The thermal-neutron cross-section and the resonance integral for the 174Yb(n,γ)175Yb reaction were measured by the activation method using a 55Mn monitor as single comparator. Analytical grade MnO2 and Yb2O3 powder samples with and without a cylindrical 1 mm Cd shield box were irradiated in an isotropic neutron field obtained from three 241Am-Be neutron sources. The gamma-ray spectra from the activated samples were measured with a calibrated n-type high-purity Ge detector. The experimental results were corrected for the correction factors calculated for thermal and epithermal neutron self-shielding effects, epithermal neutron spectrum shape and gamma-ray self attenuation. Thus, the thermal neutron cross-section for the 174Yb(n,γ)175Yb reaction is found to be 126.5 ± 6.6 b, relative to that of the 55Mn monitor. The resonance integral value for the 174Yb(n,γ)175Yb reaction is found to be 59.6 ± 8.5 b, at cadmium cut-off energy of a 0.55 eV. Using the measured cadmium ratios of 55Mn and 174Yb, the result for resonance integral of the 174Yb(n,γ)175Yb reaction has also been obtained relative to the reference value of the 55Mn monitor. The present results for the 174Yb(n,γ)175Yb reaction agree well only with the recent experimental ones obtained by Kafala et al. [1] and De Corte and Simonits [2] within uncertainty limits. However, the previously reported experimental data for the thermal neutron cross-section for this reaction are distributed between 24 and 141 b, and similarly the experimental values for the resonance integral value also show a large scatter in the range of 30-69 b. 相似文献
47.
ABSTRACTThe effects of ozone treatment (1 × 10?2 kg m?3, for up to 8 h) on quality parameters of turkey meat were investigated. Ozone was effective in inactivating microorganisms. Approximately 2.9, 2.3 and 1.9 log reductions were achieved in the counts of total aerobic mesophilic bacteria, Enterobacteriaceae and yeast-mold, respectively. Ozone caused significant changes in carbonyl contents, thiobarbituric acid reactive substances, color and pH values of the samples. Water holding capacity and cooking yield of treated samples increased significantly (p < .05). This is the first report demonstrating that quality parameters of turkey breast meat are markedly affected by ozone treatment. 相似文献
48.
This special theme aims to analyze the linkage between service-orientation and electronic markets. On the one hand, questions focus on how service-oriented thinking and service-oriented solutions provide value to electronic markets, and on the other how electronic markets improve the effectiveness of service industries, such as healthcare, telecommunications, logistics, education, and others. While the papers in the special theme section highlight selected aspects of a services-based business transformation, this preface discusses main underlying assumptions of the service evolution, underpins the link between service-orientation and electronic markets, and concludes with some developments on the emerging trans-disciplinary field of service science. 相似文献
49.
Characterization and strain‐energy‐function‐based modeling of the thermomechanical response of shape‐memory polymers 下载免费PDF全文
Shape‐memory polymers (SMPs) are an emerging class of active polymers that can be used on a wide range of reconfigurable structures and actuation devices. In this study, an epoxy‐based SMP was synthesized, and its thermomechanical behaviors were comprehensively characterized. The stress–strain behavior of the SMP was determined to be nonlinear, finite deformation in all regions. Strain‐energy‐based models were used to capture the complicated stress–strain behavior and shape‐recovery response of the SMP. Among various strain energy functions, the stretch‐based Ogden model provided the best fit to the experimental observations. Compared to the sophisticated models developed for SMPs, the strain‐energy‐based model was found to be reliable and much easier to use for practical SMP designs. © 2015 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2015 , 132, 41861. 相似文献
50.
Muge Durmaz Erhan Zor Erdal Kocabas Haluk Bingol Emine G. Akgemci 《Electrochimica acta》2011,56(15):5316
In this study, transfer reactions of alkali and alkaline-earth metal ions across a micro-water/1,2-dichloroethane (1,2-DCE) interface facilitated by a novel calix[4]arene derivative, 5,11,17,23-tetra-tert-butyl-25,27-bis(2′amino-methylpyridine)-26,28-dihydroxy calix[4]arene (APHC4), were investigated by cyclic and differential pulse voltammetry techniques. Well-defined voltammetric behavior was obtained only for K+ ion among the used metal ions. The electrochemical data were used to determine the stoichiometry and the appropriate association constant of the occurring complex between K+ ion and APHC4. The obtained steady-state voltammograms indicated that the facilitated transfer process occurs with a TIC/TID mechanism according to 1:1 stoichiometry. The logarithm of the association constant () of K(APHC4)+ complex in the DCE phase was calculated to be 6.32. Also, the availability of the facilitated transfer for the design of an amperometric screening sensor for K+ ion was evaluated in the range of 50–500 μmol dm−3. 相似文献