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911.
The paper is devoted to the study of the Aubin/Lipschitz-like property and the isolated calmness of a particular non-monotone generalized equation arising in electronics. The variational and non-smooth analysis is applied in the theory of non-regular electrical circuits involving electronic devices like ideal diodes, practical diodes, DIACs, silicon controlled rectifiers (SCR), and transistors. We also discuss the relationship of our results to the ones using classical techniques from (smooth) analysis and provide a simulation for several simple electrical circuits which are chosen in order to cover the most common non-smooth elements in electronics. The simulations of the electrical circuits discussed in this paper are performed by using Xcos (a component of Scilab). 相似文献
912.
van Howe J Lee JH Zhou S Wise F Xu C Ramachandran S Ghalmi S Yan MF 《Optics letters》2007,32(4):340-342
We demonstrate soliton self-frequency shift of more than 12% of the optical frequency in a higher-order mode solid, silica-based fiber below 1300nm. This new class of fiber shows great promise for supporting Raman-shifted solitons below 1300nm in intermediate energy regimes of 1 to 10nJ that cannot be reached by index-guided photonic crystal fibers or air-core photonic bandgap fibers. By changing the input pulse energy of 200fs pulses from 1.36 to 1.63nJ we observe Raman-shifted solitons between 1064 and 1200nm with up to 57% power conversion efficiency and compressed output pulse widths less than 50fs. Furthermore, due to the dispersion characteristics of the HOM fiber, we observe redshifted Cerenkov radiation in the normal dispersion regime for appropriately energetic input pulses. 相似文献
913.
Carbazole represents as a promising template for cancer treatment as it exists in the skeleton of numerous man-made and natural anticancer agents. In this regard, new sets of novel functionalized pyrazolo[3,4-d][1,2,3]triazin-4-ones 6a-e and 10a-e , pyrazolo[1,5-a]pyrimidines 16a,b and imidazo[1,2-b]pyrazoles 20a,b and 23a-c having carbazole moiety were efficiently synthesized, characterized, and mechanistically discussed. They were also evaluated against three human cancer cell lines (HCT-116, HepG-2, and MCF-7) and one standard human cell line (REP1) for their in vitro anticancer activity. The results declared that seven compounds 10d , 10e , 12b , 12d , 12e , 16a , and 23a had potent anticancer activity, having IC50 values in the range 2.97 to 10.31 μM. The most effective compounds 10d and 10e inhibited the growth of all screened cancer cell lines and did not reveal human toxicity. 相似文献
914.
Lipika Ray Samir Barman Hemant Nanavati Prasenjit Ghosh 《Journal of organometallic chemistry》2007,692(20):4259-4269
Synthesis, structures, and catalysis studies of gold(I) complexes of N-heterocyclic carbenes namely, a di-O-functionalized [1-(2-hydroxy-cyclohexyl)-3-(acetophenone)imidazol-2-ylidene], a mono-O-functionalized [1-(2-hydroxy-cyclohexyl)-3-(benzyl)imidazol-2-ylidene] and a non-functionalized [1,3-di-i-propyl-benzimidazol-2-ylidene], are reported. Specifically, the gold complexes, [1-(2-hydroxy-cyclohexyl)-3-(acetophenone)imidazol-2-ylidene]AuCl (1c), [1-(2-hydroxy-cyclohexyl)-3-(benzyl)imidazol-2-ylidene]AuCl (2c), and [1,3-di-i-propyl-benzimidazol-2-ylidene]AuCl (3b), were prepared from the respective silver complexes 1b, 2b, and 3a by treatment with (SMe2)AuCl in good yields following the commonly used silver carbene transfer route. The silver complexes 1b, 2b, and 3a were synthesized from the respective imidazolium halide salts by the reactions with Ag2O. The N-heterocyclic carbene precursors, 1-(2-hydroxy-cyclohexyl)-3-(acetophenone)imidazolium chloride (1a) and 1-(2-hydroxy-cyclohexyl)-3-(benzyl)imidazolium chloride (2a), were synthesized by the direct reactions of cyclohexene oxide and imidazole with chloroacetophenone and benzyl chloride respectively. The gold (1c, 2c, and 3b) and the silver (3a) complexes along with a new O-functionalized imidazolium chloride salt (1a) have been structurally characterized by X-ray diffraction. The structural studies revealed that geometries around the metal centers were almost linear in these gold and silver complexes. The gold (1c, 2c, and 3b) complexes efficiently catalyze ring-opening polymerization (ROP) of l-lactide under solvent-free melt conditions producing polylactide polymer of moderate to low molecular weights with narrow molecular weight distributions. 相似文献
915.
The solid state interaction of mono and macromolecular thiols at a disulfide heterocycle is shown to provide a versatile pathway for their speciation. 相似文献
916.
Zard SZ 《Organic & biomolecular chemistry》2007,5(2):205-213
New routes to organofluorine derivatives based mostly on the powerful xanthate radical transfer technology are described. A special emphasis is placed on the synthesis of trifluoromethyl-substituted structures, including trifluromethyl ketones and fluorinated aromatic and heteroaromatic substances of interest to the pharmaceutical and agrochemical industries. 相似文献
917.
Nine sesquiterpenes and eight flavonoids were isolated from Zingiber spectabile for the first time. Structures were determined by spectroscopic methods. The major compound zerumbone (1) was found to be the most active (IC(50) 13 microg mL(-1)) in cell growth inhibitory assay against colon carcinoma SW480 cells. 相似文献
918.
The dynamics of bound water and ions present in the minor groove of a dodecamer DNA has been decoupled from that of the long-range twisting/bending of the DNA backbone, using the minor groove binder Hoechst 33258 as a fluorescence reporter in the picosecond-resolved time window. The bound water and ions are essential structural components of the minor groove and are destroyed with the destruction of the minor groove when the dodecamer melts at high temperatures and reforms on subsequent cooling of the melted DNA. The melting and rehybridization of the DNA has been monitored by the changes in secondary structure using circular dichroism (CD) spectroscopy. The change in the relaxation dynamics of the DNA has been studied with picosecond resolution at different temperatures, following the temperature-dependent melting and rehybridization profile of the dodecamer, using time-resolved emission spectra (TRES). At room temperature, the relaxation dynamics of DNA is governed by a 40 ps (30%) and a 12.3 ns (70%) component. The dynamics of bound water and ions present in the minor groove is characterized by the 40 ps component in the relaxation dynamics of the probe bound in the minor groove of the dodecamer DNA. Analyses of the TRES taken at different temperatures show that the contribution of this component decreases and ultimately vanishes with the destruction of the minor groove and reappears again with the reformation of the groove. The dynamical behavior of bound water molecules and ions of a genomic DNA (from salmon testes) at different temperatures is also found to be consistent with that of the dodecamer. The longer component of approximately 10 ns in the DNA dynamics is found to be associated with the long-range bending/twisting of the DNA backbone and the associated counterions. The transition from bound water to free water at the DNA surface, indicative of the change in the hydration number associated with each base pair, has also been ascertained in the case of the genomic DNA at different temperatures by employing densimetric and acoustic techniques. 相似文献
919.
Bouazza Fahsi Kouider Halim Benrahou Baghdad Krour Abdeloauhed Tounsi Samir Benyoucef E Abbas Adda Bedia 《Acta Mechanica Solida Sinica》2011,24(6):519-526
In this paper, the effect of time-dependent deformations (such as shrinkage and creep) on the interfacial stresses between an RC beam and FRP plate is presented. For this end, a closed-form solution for such stresses in externally FRP plated RC beams including creep and shrinkage effects is presented. The developed model is formulated to predict the interfacial stresses at time ‘t’, in which the RC beams have been already subjected to creep and shrinkage effects. The adherend shear deformations have been included in the present theoretical analysis by assuming a parabolic shear stress through the thickness of the RC beam and the FRP panel. Contrary to some existing studies, the assumption that both RC beam and FRP panel have the same curvature is not used in the present investigation. This research is helpful for the understanding on mechanical behavior of the interface and design of the FRP-RC hybrid structures. 相似文献
920.
Zhao Z Husainy S Stoudemayer CT Smith GD 《Physical chemistry chemical physics : PCCP》2011,13(39):17809-17817
The reactive uptake of NO(3) by particles containing four unsaturated fatty acid species was studied for the first time in a flow tube reactor coupled to a chemical ionization mass spectrometer (CIMS). Using a mixed-phase relative rates technique, the reactive uptake coefficients, γ(part), were determined to be (0.27 ± 0.06) for oleic acid (OA), (0.53 ± 0.12) for linoleic acid (LA), (0.72 ± 0.17) for linolenic acid (LNA), and (1.01 ± 0.18) for conjugated linoleic acid (CLA) in N(2) bath gas. In the presence of 20% O(2), their uptake coefficients are (0.31 ± 0.09) for OA, (0.55 ± 0.12) for LA, (0.78 ± 0.17) for LNA, and (1.08 ± 0.17) for CLA. All the uncertainties are 2σ and represent precision only. The products of the NO(3) reactions with these organic particles were studied in the presence and absence of O(2) using CIMS. It was found that the detected yields and compositions of the products were substantially different with or without O(2). Based on the observed products and general gas-phase chemistry of NO(3) radicals, a reaction mechanism is proposed for NO(3) reactions with unsaturated organic particles. The atmospheric implications of the heterogeneous chemical processes involving NO(3) are also discussed. 相似文献