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61.
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In this paper, a new channel drop filter in two dimensional photonic crystals with mirror cavities is proposed. In the structure,
three cavities are used. One is used for a resonant tunneling-based channel drop filter. The others are used to realize reflection
feedback in the bus waveguide, which consists of a point defect micro-cavity side-coupled to a waveguide. The simulation results
by using the finite-difference time-domain method conclude 98% output efficiency. 相似文献
64.
Adel A.-H. Abdel-Rahman 《Monatshefte für Chemie / Chemical Monthly》2008,139(3):289-297
Summary. A series of peptide and dipeptide derivatives conjugated with an indazole residue were synthesized. The new compounds were
evaluated in vitro for cytotoxicity against Hepatitis-A virus (HAV-27), Herpes Simplex virus-1 (HSV-1), and Hepatitis-B virus (HBV) and showed moderate to high activity. 相似文献
65.
Summary Binary and ternary complexes of copper(II) with glycyl-L-tyrosine and an amino acid ester were investigated by potentiometric and spectrophotometric techniques. The kinetics of base hydrolysis of the above esters in the presence of copper(II)-glycyl-L-tyrosine complex was studied at 30°C. 相似文献
66.
Self-interstitial interactions causing volume expansion in bcc Fe are studied through an idealized microstructure evolution model in which only self-interstial atoms (SIAs) are inserted. Using a combination of non-equilibrium molecular dynamics simulations and a metadynamics algorithm, meta-stable SIA clusters are observed to nucleate and grow into dislocation loops or localized amorphous phases, both contributing to swelling behavior persisting well beyond the atomistic time scale. A non-monotonic local density variation with dose rate is found and attributed to competing evolutions of different defective structures. 相似文献
67.
68.
Hafedh Hajlaoui Soumaya Arraouadi Emira Noumi Kaïss Aouadi Mohd Adnan Mushtaq Ahmad Khan Adel Kadri Mejdi Snoussi 《Molecules (Basel, Switzerland)》2021,26(12)
Herbs and spices have been used since antiquity for their nutritional and health properties, as well as in traditional remedies for the prevention and treatment of many diseases. Therefore, this study aims to perform a chemical analysis of both essential oils (EOs) from the seeds of Carum carvi (C. carvi) and Coriandrum sativum (C. sativum) and evaluate their antioxidant, antimicrobial, anti-acetylcholinesterase, and antidiabetic activities alone and in combination. Results showed that the EOs mainly constitute monoterpenes with γ-terpinene (31.03%), β-pinene (18.77%), p-cymene (17.16%), and carvone (12.20%) being the major components present in C. carvi EO and linalool (76.41%), γ-terpinene (5.35%), and α-pinene (4.44%) in C. sativum EO. In comparison to standards, statistical analysis revealed that C. carvi EO showed high and significantly different (p < 0.05) antioxidant activity than C. sativum EO, but lower than the mixture. Moreover, the mixture exhibited two-times greater ferric ion reducing antioxidant power (FRAP) (IC50 = 11.33 ± 1.53 mg/mL) and equipotent chelating power (IC50 = 31.33 ± 0.47 mg/mL) than the corresponding references, and also potent activity against 2,2-diphenyl-1-picrylhydrazyl (DPPH) (IC50 = 19.00 ± 1.00 mg/mL), β-carotene (IC50 = 11.16 ± 0.84 mg/mL), and superoxide anion (IC50 = 10.33 ± 0.58 mg/mL) assays. Antimicrobial data revealed that single and mixture EOs were active against a panel of pathogenic microorganisms, and the mixture had the ability to kill more bacterial strains than each EO alone. Additionally, the anti-acetylcholinesterase and α-glucosidase inhibitory effect have been studied for the first time, highlighting the high inhibition effect of AChE by C. carvi (IC50 = 0.82 ± 0.05 mg/mL), and especially by C. sativum (IC50 = 0.68 ± 0.03 mg/mL), as well as the mixture (IC50 = 0.63 ± 0.02 mg/mL) compared to the reference drug, which are insignificantly different (p > 0.05). A high and equipotent antidiabetic activity was observed for the mixture (IC50 = 0.75 ± 0.15 mg/mL) when compared to the standard drug, acarbose, which is about nine times higher than each EO alone. Furthermore, pharmacokinetic analysis provides some useful insights into designing new drugs with favorable drug likeness and safety profiles based on a C. carvi and C. sativum EO mixture. In summary, the results of this study revealed that the combination of these EOs may be recommended for further food, therapeutic, and pharmaceutical applications, and can be utilized as medicine to inhibit several diseases. 相似文献
69.
Synthesis, characterization and properties of novel thermally stable poly(urethane-oxazolidone) elastomers 总被引:2,自引:0,他引:2
Oxazolidone-incorporated polyurethane elastomers based on hydroxyl terminated polycaprolactone, were synthesized and characterized. Reaction of epoxy-terminated polyurethane with isocyanate librated from a blocked polyisocyanate was the strategy followed. The reaction condition was optimized through preparation of model oxazolidones. Epoxy-terminated polyurethanes were prepared from reaction of glycidol with NCO-terminated polyurethane prepolymers and curing agent was synthesized from the reaction of trimethylol propane, toluene diisocyanate and N-methyl-aniline. Incorporation of heterocyclic oxazolidone groups into the polyurethane backbone caused improvements in thermal and mechanical properties. Investigation of structure-property relationship for prepared elastomers showed that the main determining factors for observed properties were crosslink density, crystallinity and content of oxazolidone rings. 相似文献
70.
Nadjette Debbouche Shaher Momani Adel Ouannas Mohd Taib Shatnawi Giuseppe Grassi Zohir Dibi Iqbal M. Batiha 《Entropy (Basel, Switzerland)》2021,23(3)
This article investigates a non-equilibrium chaotic system in view of commensurate and incommensurate fractional orders and with only one signum function. By varying some values of the fractional-order derivative together with some parameter values of the proposed system, different dynamical behaviors of the system are explored and discussed via several numerical simulations. This system displays complex hidden dynamics such as inversion property, chaotic bursting oscillation, multistabilty, and coexisting attractors. Besides, by means of adapting certain controlled constants, it is shown that this system possesses a three-variable offset boosting system. In conformity with the performed simulations, it also turns out that the resultant hidden attractors can be distributively ordered in a grid of three dimensions, a lattice of two dimensions, a line of one dimension, and even arbitrariness in the phase space. Through considering the Caputo fractional-order operator in all performed simulations, phase portraits in two- and three-dimensional projections, Lyapunov exponents, and the bifurcation diagrams are numerically reported in this work as beneficial exit results. 相似文献