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51.
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In this paper, the L’Hospital rule for evaluating limits of complex matrix functions is introduced. We present some specific examples on certain matrix functions showing the applicability of our approach.  相似文献   
53.
This study addresses the formation of anisotropic compact star models in the background of f(T,(T))gravity(where T and (T) represent the torsion and trace of th...  相似文献   
54.
A simple, rapid, specific and sensitive thin layer chromatographic (TLC) method has been developed for the quantitative estimation of mevalonic acid (MVA) in leaves of medicinal plants; Artemisia annua, Psorelia corylifolia, Vinca rosea, Withania somnifera and Barleria proinites. The assay procedure involved conversion of MVA to its lactone, mevalonolactone (MVAL). Mevalonic acid was extracted from the leaf tissues of plants. Separation of MVAL was carried out on silica gel 60 F254 TLC plates using benzene:acetone (3:2) as the mobile phase. The densitometric determination of MVAL was performed at 600 nm after derivatization with anisaldehyde reagent in absorption–reflectance mode. The method was validated over the linearity range of 100–500 ng spot?1 and correlation coefficient for the calibration curve was >0.99. The average recovery of MVAL, used as internal standard, was higher than 98%. The lower limit of detection was found to be 50 ng spot?1.  相似文献   
55.
Summary The Korteweg-de Vries equation for ion acoustic waves in the presence of weakly relativistic ion streaming velocity is derived in a magnetic plasma. It is found that relativistic effects are important in the solitary wave propagation for both fast and slow modes. Earlier results are reconfirmed. To speed up publication, the authors of this paper have agreed to not receive the proofs for correction.  相似文献   
56.
A general solution of the equilibrium equations is obtained for a half-space with a fixed boundary and arbitrary but axisymmetric distribution of body forces and body couples in the interior of the half-space. Few particular cases have been investigated in detail. The stresses have been obtained at the boundary and the displacements have been obtained in the interior of the half-space. Numerical results have been displayed graphically.
Zusammenfassung Eine allgemeine lösung für Gleichgewicht eines Halbraums mit festem Rand und einer beliebigen, aber antisymmetrischen Verteilung von Körperkräften und Körpermomenten im Inneren wird gefunden. Einige Spezialfälle wurden ansführlich erforscht. Die Spannungen am Rand und die Verschiebungen im Inneren des Halbraums wurden erhalten. Numerische Resultate wurden graphisch dargestellt.
  相似文献   
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In this work, we will report a combined experimental and theoretical study on molecular structure, vibrational spectra, NBO and UV spectral analysis of 2-chlorobenzonitrile (2-ClBN). The FT-IR solid phase (4000-400 cm(-1)), and FT-Raman spectra (3500-50 cm(-1)) of 2-ClBN was recorded. The molecular geometry, harmonic vibrational frequencies and bonding features of 2-ClBN in the ground state have been calculated by using the density functional methods (BLYP, B3LYP) with 6-31G(d,p) as basis set. The assignments of the vibrational spectra have been carried out with the help of normal co-ordinate analysis (NCA) following the Scaled Quantum Mechanical Force Field Methodology (SQMFF). Stability of the molecule arising from hyper conjugative interactions, charge delocalization has been analyzed using natural bond orbital (NBO) analysis. The results show that charge in electron density (ED) in the σ* and π* anti bonding orbitals and E2 energies confirms the occurrence of ICT (Intra molecular Charge Transfer) within the molecule. The UV spectrum was measured in ethanol solution. The energy and oscillator strength calculated by Time-Dependent Density Functional Theory (TD-DFT) results complements with the experimental findings. The calculated HOMO and LUMO energies also confirm that charge transfer occurs within the molecule. Finally calculated results were applied to simulated Infrared and Raman spectra of the title compound which show good agreement with observed spectra.  相似文献   
59.
To satisfy the ever-increasing energy demands, it is of the utmost importance to develop electrochemical materials capable of producing and storing energy in a highly efficient manner. Titanium dioxide (TiO2) has recently emerged as a promising choice in this field due to its non-toxicity, low cost, and eco-friendliness, in addition to its porosity, large surface area, good mechanical strength, and remarkable transport properties. Here, we present titanium dioxide nanoplates/polyvinylidene fluoride (TiO2/PVDF) membranes prepared by a straightforward hydrothermal strategy and vacuum filtration process. The as-synthesized TiO2/PVDF membrane was applied for energy storage applications. The fabricated TiO2/PVDF membrane served as the negative electrode for supercapacitors (SCs). The electrochemical properties of a TiO2/PVDF membrane were explored in an aqueous 6 M KOH electrolyte that exhibited good energy storage performance. Precisely, the TiO2/PVDF membrane delivered a high specific capacitance of 283.74 F/g at 1 A/g and maintained capacitance retention of 91% after 8000 cycles. Thanks to the synergistic effect of TiO2 and PVDF, the TiO2/PVDF membrane provided superior electrochemical performance as an electrode for a supercapacitor. These superior properties will likely be used in next-generation energy storage technologies.  相似文献   
60.
Resin composites have been widely used in dental restoration. However, polymerization shrinkage and resultant bacterial microleakage are major limitations that may lead to secondary caries. To overcome this, a new type of antibacterial resin composite containing ciprofloxacin-loaded silver nanoparticles (CIP-AgNPs) were synthesized. The chemical reduction approach successfully produced CIP-AgNPs, as demonstrated by FTIR, zeta potential, scanning electron microscopy, and ultraviolet-visible (UV-vis) spectroscopy. CIP-AgNPs were added to resin composites and the antibacterial activity of the dental composite discs were realized against Enterococcus faecalis, Streptococcus mutans, and the Saliva microcosm. The biocompatibility of modified resin composites was assessed and mechanical testing of modified dental composites was also performed. The results indicated that the antibacterial activity and compressive strength of resin composites containing CIP-AgNPs were enhanced compared to the control group. They were also biocompatible when compared to resin composites containing AgNPs. In short, these results established strong ground application for CIP-AgNP-modified dental composite resins.  相似文献   
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