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101.
In this paper, we study the applicability of the iterative asynchronousalgorithms to systems of first order differential equations.These algorithms can be implemented on monoprocessors as wellas on multiprocessors, therefore this study extends Picard'smethod and opens a future perspective for treating differentialsystems in a parallel and asynchronous manner using multiprocessors 相似文献
102.
103.
This paper describes an O.R. approach designed to assist management in the task of identifying and subsequently quantifying potential areas for improvement in the effectiveness of maintenance. It is argued that the information commonly collected and made available to management is inadequate when compared against the true information requirements associated with this process. A survey technique incorporating the collection and analysis of subjective data was designed as a means by which to overcome this shortcoming. This approach is described within the context of two industrial case studies. The results obtained from the case studies are discussed in detail, together with problems which arose in practice with regard to the design and implementation of the methods described. 相似文献
104.
105.
Christopher A Reid Brendan EL Adams Damian Myers Terence J O'Brien David A Williams 《BMC neuroscience》2008,9(1):59
Background
Excitotoxicity occurs in a number of pathogenic states including stroke and epilepsy. The adaptations of neuronal circuits in response to such insults may be expected to play an underlying role in pathogenesis. Synchronous neuronal firing can be induced in isolated hippocampal slices and involves all regions of this structure, thereby providing a measure of circuit activity. The effect of an excitotoxic insult (kainic acid, KA) on Mg2+-free-induced synchronized neuronal firing was tested in organotypic hippocampal culture by measuring extracellular field activity in CA1 and CA3. 相似文献106.
Haddou EL Ghazi Anouar Jorio Izeddine Zorkani Mohamed Ouazzani-Jamil 《Optics Communications》2008,281(12):3314-3319
Electroluminescence (EL) properties of InxGa1−xN/AlyGa1−yN/GaN/SiC diode were studied. The spectral range for which EL spectra were recorded is 1–3.5 eV. Room temperature EL was obtained for forward bias (3.18 V, 220 μA) at 446.067 nm (blue luminescence band), 606.98 nm (yellow luminescence band) and 893.84 nm (Infrared luminescence band). The EL temperature dependence shows that, BL band is mostly given by e–h recombination corresponding to indium composition equal to 0.17 ± 0.01 and 0.14 ± 0.02 obtained theoretically and experimentally, respectively. The yellow band is generally weak and absent at low temperature. The IRL band is more consistent with the DAP recombination and could be explained by the thermal activation of Mg states. The luminescence bands shift to lower energies is due probably to the larger potential fluctuations effect. 相似文献
107.
108.
E. H. EL Kinani 《International Journal of Theoretical Physics》2000,39(6):1457-1462
We review the R-deformed Heisenberg algebra and its Fock space representation.We construct the R-deformed quantum mechanics in N dimensions, and proposea new R-deformed Virasoro algebra. 相似文献
109.
Jorge Ruiz‐Olles Petr Slavik Nicole K. Whitelaw David K. Smith 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2019,131(13):4217-4222
1,3:2,4‐Dibenzylidene‐d ‐sorbitol (DBS), a simple, commercially relevant compound, was found to self‐assemble as a result of intermolecular noncovalent interactions into supramolecular gels in deep eutectic solvents (DESs) based on choline chloride combined with alcohols/ureas. DBS formed gels at a loading of 5 % w/v. Rheology confirmed the gel‐like nature of the materials, electron microscopy and X‐ray diffraction indicated underpinning nanofibrillar DBS networks, and differential scanning calorimetry showed the DES nature of the liquid‐like phase was retained. The ionic conductivities of the gels were similar to those of the unmodified DESs, thus proving the deep eutectic nature of the ionic liquid‐like phase. Gelation was tolerant of ionic additives Li+, Mg2+, and Ca2+; the resulting gels had similar conductivities to electrolyte dissolved in the native DES. The low‐molecular‐weight gelator DBS is thus a low‐cost additive that forms gels in DESs from readily available constituents, with conductivity levels suitable for practical applications. 相似文献
110.
Nor EL Houda Tahiri Hamza Saghrouchni Noureddine Hamamouch Mostafa El Khomsi Abdulhakeem Alzahrani Ahmad Mohammad Salamatullah Lyoussi Badiaa Lalla Aicha Lrhorfi 《Molecules (Basel, Switzerland)》2022,27(23)
During the postharvest period, citrus fruits are exposed to Penicillium italicum, Penicillium digitatum, and Geotrichum candidum. Pesticides such as imazalil (IMZ), thiabendazole (TBZ), orthophenylphenol (OPP), and guazatine (GUA) are commonly used as antifungals. Glyphosate (GP) is also used in citrus fields to eliminate weed growth. The sensitivity of fungal pathogens of citrus fruit to these pesticides and 1,8-cineole was evaluated, and the effect of GP on the development of cross-resistance to other chemicals was monitored over a period of 3 weeks. IMZ most effectively inhibited the mycelial growth and spore germination of P. digitatum and P. italicum, with minimum inhibitory concentrations (MICs) of 0.01 and 0.05 mg/mL, respectively, followed by 1,8-cineole, GP, and TBZ. 1,8-Cineole and GP more effectively inhibited the mycelial growth and spore germination of G. candidum, with minimum inhibitory concentrations (MICs) of 0.2 and 1.0 mg/mL, respectively, than OPP or GUA. For the spore germination assay, all substances tested showed a total inhibitory effect. Subculturing the fungal strains in culture media containing increasing concentrations of GP induced fungal tolerance to GP as well as to the fungicides. In soil, experiments confirmed that GP induced the tolerance of P. digitatum to TBZ and GP and the tolerance of P. italicum to IMZ, TBZ, and GP. However, no tolerance was recorded against 1,8-cineole. In conclusion, it can be said that 1,8-cineole may be recommended as an alternative to conventional fungicides. In addition, these results indicate that caution should be taken when using GP in citrus fields. 相似文献