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41.
A new ternary composite of 1T-molybdenum disulfide, hexagonal tungsten trioxide, and reduced graphene oxide (M-W-rGO) is synthesized by using a one-pot hydrothermal process. The synergetic effect of 1T-MoS2 and hexa-WO3 nanoflowers improves the electrochemical performance for supercapacitors by inducing additional active sites and hexagonal tunnels, respectively, which lead to high storage capacity and easy transfer of electrolyte ions. The ternary M-W-rGO composite has a high specific capacitance of 836 F g−1 at 1 A g−1, which is nearly twice that of binary composites of M-rGO and W-rGO with high capacitance retention of 86.35 % after 3000 cycles at a high current density of 5 A g−1. This study provides a new ternary composite that can be used as an electrode material for high-performance supercapacitors.  相似文献   
42.
Khan  Jehangir  Sadia  Maria  Shah  Syed Wadood Ali  Naz  Robina  Ali  Faiz 《Journal of fluorescence》2021,31(6):1759-1770
Journal of Fluorescence - The ligand 2,6-bis(E)-4-methylbenzylidine)-cyclohexan-1-one sensor has been synthesized as a fluorescence-on sensor/probe for the trace level detection of chromium III...  相似文献   
43.
Simple, isocratic and rapid RP‐HPLC method has been developed for the simultaneous analysis of gemifloxacin and H2‐receptor antagonists i.e. Cimetidine, Famotidine and Ranitidine, in bulk, pharmaceutical formulation and human serum. Separation was achieved on the RP‐Mediterranea column [C18 (250 × 4.6 mm, 5 μ)] at ambient temperature using mobile phase consisting of acetonitrile: methanol: water (20:28:52 v/v/v pH 2.8 adjusted by phosphoric acid). Flow rate was 1.0 mL/min with an average operating pressure of 180 kg/cm2. Gatifloxacin (GATI) was used as an internal standard (IS). Quantitation was achieved with UV detection at 221, 256 and 267 nm, respectively. Linear calibration curves, at concentration ranges of 0.05‐37.5 μgmL‐L with a correlation coefficient of ±0.9994. The detection and quantification limits were in the ranges of 0.023‐0.250 μgmL‐L and 0.071‐0.756 μgmL‐L, respectively. Friedman's and Student's t‐test were applied to correlate these results. Method was validated in terms of selectivity, linearity, precision, robustness, recovery, limits of detection and quantitation and is applicable to the routine analysis of GFX and H2‐receptor antagonists, alone or in combination.  相似文献   
44.
Russian Journal of Coordination Chemistry - We have reported synthesis of complex [Rh(COD)(L{Me})Cl] (III), where L{Me} (II) is N-(1-methylpyridin-4(1H)-ylidene)benzamide and COD is...  相似文献   
45.
In this paper we construct the conservation laws for the Camassa–Holm equation, the Dullin–Gottwald–Holm equation (DGH) and the generalized Dullin–Gottwald–Holm equation (generalized DGH). The variational derivative approach is used to derive the conservation laws. Only first order multipliers are considered. Two multipliers are obtained for the Camassa–Holm equation. For the DGH and generalized DGH equations the variational derivative approach yields two multipliers; thus two conserved vectors are obtained.  相似文献   
46.
47.
The present investigation deals with the interaction of 2-aminopyridine, 3-aminopyridine, and 4-aminopyridine with chromium and manganese ferrocyanides. Chromium ferrocyanide possesses better adsorbing properties than manganese ferrocyanide. Maximum uptake was observed at neutral pH (pH 7.0). The adsorption data obtained at neutral pH are fitted in a Langmuir adsorption isotherm. The adsorption behavior of the aminopyridines studied follows the order 3-aminopyridine >4-aminopyridine >2-aminopyridine. The infrared spectral studies of adsorption adducts indicate that adsorption takes place through interactions between the adsorbate molecule and the outer divalent metal ion of metal ferrocyanides. From these studies, it is clear that metal ferrocyanides and metal ions play a major role in the stabilization of organic molecules through their surface activity in the prebiotic environment. Copyright 2000 Academic Press.  相似文献   
48.
Six oleanane‐type triterpenoid esters were isolated from the golden flowers of Tagetes erecta. Spectral studies characterized their structures as 3‐O‐[(9Z)‐hexadec‐9‐enoyl]erythrodiol ( 1 ), 11α,12α:13β,28‐diepoxyoleanan‐3β‐yl (9Z)‐hexadec‐9‐enoate ( 2 ), 13β,28‐epoxyolean‐11‐en‐3β‐yl (9Z)‐hexadec‐9‐enoate ( 3 ), 28‐hydroxy‐11‐oxoolean‐12‐en‐3β‐yl (9Z)‐hexadec‐9‐enoate ( 4 ), 3‐O‐[(9Z‐hexadec‐9‐enoyl]‐β‐amyrin ( 5 ), and 11‐oxoolean‐12‐en‐3β‐yl (9Z)‐hexadec‐9‐enoate ( 6 ). Compounds 1 – 4 and 6 are new natural products, while the known 5 was isolated for the first time from the genus Tagetes, from which only one triterpenoid has earlier been obtained. Aerial oxidation (autoxidation) converted amyrin 1 into 2 – 4 and transformed amyrin 5 into 6 . The configuration of 1 – 6 and an autoxidation mechanism (Scheme) involving the formation of the intermediate 11α‐hydroxyolean‐12‐ene derivatives 1b and 5b on thermal decomposition of the labile 11α‐OOH derivatives 1a and 5a , respectively, under neutral conditions are discussed. For the first time, the reactivity of the allylic H? C(11) bond of triterpenoids of type 1 and 5 toward aerial oxidation was observed. The long‐chain ester group at C(3) of 1 and 5 may be responsible for their labile nature, as β‐amyrin ( 7 ), erythrodiol ( 8 ), and ursolic acid were found to be inert toward autoxidation.  相似文献   
49.
Anisotropic silver nanoparticles (NPs) were successfully employed to color the wool fabrics in this study. The modified wool fabrics exhibited brilliant colors due to the localized surface plasmon resonance (LSPR) properties of silver NPs. The colors of wool fabrics altered with the morphologies of silver NPs. These modified wool fabrics were characterized by scanning electron microscopy (SEM) and X-ray photoelectron spectroscopy (XPS). The results indicated that anisotropic silver NPs were effectively assembled on the surface of wool fibers when the solution pH and temperature was about 4 and 40°C, respectively. This assembling of silver NPs on the wool fibers was realized by the electrostatic interaction between wool fibers and silver NPs. This technique was also applied to gold NPs. The fabrics treated with anisotropic silver NPs showed high antibacterial activity against the bacteria of Escherichia coli. This study opens a new approach to color and functionalize conventional textile materials.  相似文献   
50.
1,6-Bis(benzimidaz-2-yl)-3,4-dithiahexane ligand (L) and its mercury halide complexes were prepared and characterised. The elemental analysis, molecular conductivity, FT-Raman, FT-IR (mid, far), 1H, 13C NMR and geometry optimization in MOPAC using MNDOd parameter on CACHE, prove the existence of neutral, mononuclear and the distorted tetrahedral [Hg(L)X2] complexes. In all the three complexes, the ligand acts as a chelating bidentate, through two of the bridging sulphur atoms and together with the monodentate coordination of the two anionic halide ligands to the metal centre forming a possible 4-coordinate compounds. The antimicrobial activities of free ligand, its hydrochlorinated salt, mercury halides and the complexes are evaluated using disk diffusion method in dimethyl sulfoxide (DMSO) as well as the minimal inhibitory concentration (MIC) dilution method, against 10 bacteria. The obtained results from disk diffusion method are assessed in side-by-side comparison with those of Penicillin-g, Ampicillin, Cefotaxime, Vancomycin, Oflaxacin and Tetracyclin well-known antibacterial agents. The results from dilution procedure are compared with Gentamycin as antibacterial and Nystatin as antifungal. The antifungal activities are reported on five yeast cultures namely Candida albicans, Kluyveromyces fragilis, Rhodotorula rubra, Debaryomyces hansenii and Hanseniaspora guilliermondii, and the results are referenced with Nystatin, Ketaconazole and Clotrimazole, commercial antifungal agents. In most cases, the compounds show broad-spectrum (Gram+ & Gram bacteria) activities that are comparatively, slightly less active or equipotent to the antibiotic and antifungal agents in the comparison tests.  相似文献   
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