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991.
A novel series of fluorine‐containing quinoline hybrid thiosemicarbazide analogues ( 8a–8l ) were synthesized and tested for their biological activities. The antibacterial results demonstrated that compounds 8d and 8l [minimal inhibitory concentration (MIC) 62.5 μg/mL] were shown to have higher biological activity than ampicillin against Escherichia coli. Compound 8b (MIC 25 μg/mL) was shown to have the highest activity than was ampicillin against Staphylococcus aureus. The antifungal results demonstrated that compound 8j (MIC 100 μg/mL) has shown good activity. Most of the targeted compounds have shown potent antimalarial activity. Compounds 8d (0.19 μg/mL), 8g (0.30 μg/mL), 8h (0.36 μg/mL), 8k (0.10 μg/mL), 8l (0.28 μg/mL), 8k (0.10 μg/mL), and 8l (0.28 μg/mL) have notable activity than does the reference drug quinine. Compounds 8d (0.27 μg/mL), 8g (0.30 μg/mL), and 8k (0.17 μg/mL) have shown excellent activity against chloroquine‐resistant strain. The MTT assay performed on peripheral blood lymphocyte cultures showed a high percentage of lymphocyte viability [ 8d (99.64), 8g (99.46), 8h (98.83), and 8k (99.51)] at a maximum dose (10 μg/mL), depicting no cytotoxicity of these compounds on human lymphocytes in vitro. A molecular docking study was performed on Pf‐DHFR‐TS inhibitor. A molecular dynamics study has shown compound 8g to have better affinity with protein. ADME‐Tox and pharmacophore study of synthesized compounds suggested prediction of active site.  相似文献   
992.
At the energy regimes close to Planck scales, the usual structure of Lorentz symmetry fails to address certain fundamental issues and eventually breaks down, thus paving the way for an alternative road map. It is thus argued that some subgroup of proper Lorentz group could stand consistent and might possibly help us to circumvent this problem.It is this subgroup that goes by the name of Very Special Relativity(VSR). Apart from violating rotational symmetry,VSR is believed to preserve the very tenets of special relativity. The gaugeon formalism due to type-I Yokoyama and type-II Izawa are found to be invariant under BRST symmetry. In this paper, we analyze the scope of this invariance in the scheme of VSR. Furthermore, we will obtain VSR modified Lagrangian density using path integral derivation. We will explore the consistency of VSR with regard to these theories.  相似文献   
993.
A traffic model based on the road surface conditions during adverse weather is presented. The surface of a road is affected by snow, compacted snow, and ice, which affects the traffic behavior. In this paper, a new macroscopic traffic flow model based on the transition velocity distribution is proposed which characterizes traffic alignment under adverse weather conditions. Two examples are considered to illustrate the effect of the transition velocity behavior on traffic velocity and density. Simulation results are presented which show that this model provides a more accurate characterization of traffic flow behavior than the well known Payne–Whitham model. The proposed model can be used to reduce accidents and improve road safety during adverse weather conditions.  相似文献   
994.
In the first decade of the 19th century, an English chemist, William Wollaston, invented an arrangement of birefringent prisms that splits a beam of light into two spatially separated beams with orthogonal polarizations. We have constructed similar devices for neutrons using triangular cross-section solenoids and employed them for Spin Echo Scattering Angle Measurement (SESAME). A key difference between birefringent neutron prisms and their optical analogues is that it is hard to embed the former in a medium which has absolutely no birefringence because this implies the removal of all magnetic fields. We have overcome this problem by using the symmetry properties of the Wollaston neutron prisms and of the overall spin echo arrangement. These symmetries cause a cancellation of Larmor phase aberrations and provide robust coding of neutron scattering angles with simple equipment.  相似文献   
995.
Colloid and Polymer Science - Die Oligo-Diamine aus Adipinsäure und 1,6-Diaminohexan H-[B-A] n -B-H (n=1–5) sowie die Oligo-Aminosäuren H-[B-A] n -OH (n=4,5) wurden nach der Methode...  相似文献   
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We report the observation of spatial variation of the bandgap energy of In0.53Ga0.47As in high quality epitaxial samples grown lattice matched to InP. Nine samples grown by three different techniques (LPE, VPE and MBE) were investigated and they all showed this apparently random spatial variation. A bandgap variation as large as 15 meV was observed over distances of the order of 1 mm, an effect corresponding to two percent of bandgap energy.  相似文献   
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