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71.
We study the generalized second law of thermodynamics in the presence of non-interacting magnetic field and new modified Chaplygin gas with FRW universe. In this scenario, we investigate the validity of this law on Hubble, apparent, particle and event horizons. It is found that this law is respected on all horizons for specific values of the model parameters except on the event horizon where it does not hold for short time but remains valid otherwise. Finally, we explore the statefinders and Om diagnostic to check the viability of the present cosmological model.  相似文献   
72.
In the present study, naphthyl acetohydrazide (HL) ligand was prepared and used for the synthesis of new six amorphous transition metal (Co(II), Ni(II), Cu(II), Zn(II), Pb(II), Cd(II)) complexes. All the compounds were characterized by elemental analysis, UV-vis, FT-IR, 1H- and 13C-NMR, and Matrix-Assisted Laser Desorption Ionization (MALDI). The solubilization study was carried out by estimating the interaction between the metal complexes with surfactants viz. sodium stearate (SS) and Cetyltrimethylammonium bromide (CTAB). UV-Visible spectroscopy was employed to determine partitioning and binding parameters, whereas electrical conductivity measurements were employed to estimate critical micellar concentration (CMC), the extent of dissociation, and free energy of micellization. The CT-DNA interaction of synthesized compounds with DNA represents the major groove binding. The synthesized ligand and metal complexes were also tested against bacterial and fungal strains and it has been observed that Cu(II) complex is active against all the strains except Candida albicans, while Cd(II) complex is active against all bacterial and fungal strains except Pseudomonas. Among all compounds, only the Pd(II) complex shows reasonable activity against cervical cancer HeLa cell lines, representing 97% inhibition.  相似文献   
73.
Tin diselenide (SnSe2), as an anode material, has outstanding potential for use in advanced lithium-ion batteries. However, like other tin-based anodes, SnSe2 suffers from poor cycle life and low rate capability due to large volume expansion during the repeated Li+ insertion/de-insertion process. This work reports an effective and easy strategy to combine SnSe2 and carbon nanotubes (CNTs) to form a SnSe2/CNTs hybrid nanostructure. The synthesized SnSe2 has a regular hexagonal shape with a typical 2D nanostructure and the carbon nanotubes combine well with the SnSe2 nanosheets. The hybrid nanostructure can significantly reduce the serious damage to electrodes that occurs during electrochemical cycling processes. Remarkably, the SnSe2/CNTs electrode exhibits a high reversible specific capacity of 457.6 mA h g−1 at 0.1 C and 210.3 mA h g−1 after 100 cycles. At a cycling rate of 0.5 C, the SnSe2/CNTs electrode can still achieve a high value of 176.5 mA h g−1, whereas a value of 45.8 mA h g−1 is achieved for the pure SnSe2 electrode. The enhanced electrochemical performance of the SnSe2/CNTs electrode demonstrates its great potential for use in lithium-ion batteries. Thus, this work reports a facile approach to the synthesis of SnSe2/CNTs as a promising anode material for lithium-ion batteries.  相似文献   
74.

Fukuyama reaction for the synthesis of multifunctional aldehydes, secondary amines and ketones has gained considerable importance in synthetic organic chemistry because of mild reaction conditions. The use of thioesters in both Fukuyama aldehydes and ketones synthesis is highly attractive for organic chemists as they are easily accessible from corresponding carboxylic acids. Fukuyama–Mitsunobu reaction utilizes 2-nitrobenzenesulfonyl (Ns) for the protection/activation/deprotection of primary amines to afford secondary amines in good yields and high enantioselectivities. This review presents recent synthetic developments and applications of Fukuyama reaction for the synthesis of aldehydes, secondary amines and ketones.

Graphic abstract
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75.
In the quest for new drug candidates for the safe treatment of parasitic diseases like leishmaniasis, a series of heteroleptic pentavalent antimonials of the type [SbR3(OOCR′)2] were synthesized and characterized using elemental analysis, Fourier transform infrared spectroscopy and multinuclear (1H and 13C) NMR spectroscopy. The carboxylate moieties are predominantly substituted benzoates with some complexes that fit in acetato or nicotinato ligands. The crystal structures of [Sb(p‐Tol)3(p‐CH3C6H4COO)2], [Sb(p‐Tol)3(3,5‐Cl2C6H3COO)2] and [Sb(p‐Tol)3(3‐nicotinato)2] were determined crystallographically and shown to adopt geometries intermediate between trigonal bipyramidal and square pyramidal, and essentially monomeric with a five‐coordinated Sb center. The leishmanicidal activity was assessed against the Leishmania tropica KWH23 parasite, and the cytotoxicity level was also measured on human macrophage blood cells. It was observed that IC50 of the antimonials was 100‐fold superior as compared with the standard antimonial drug used. Cytotoxicity results showed that these antimonials are highly active even at low concentrations and are biocompatible with human macrophages, making them highly promising drug candidates for further investigation. Copyright © 2016 John Wiley & Sons, Ltd.  相似文献   
76.
Ammonium salts, (NH4)6HPMo11MO40 (M = Ni, Co, Fe), have been investigated for the oxidation of propane, with molecular oxygen, at temperature ranging between 380 °C and 420 °Cafter in-situ pre-treatment performed at two heating rate of 5 or 9 °C/min. They were characterized by BET method, XRD, 31P NMR, UV-Vis and IR techniques. The catalysts were found active in the propane oxidation and selective to propene or acrolein, in particular for samples pre-treated with the heating rate of 9 °C/min.  相似文献   
77.
This study highlights the utility of new pyridinium based cationic surfactants, N-(n-heptyl)-3-methylpyridinium bromide (Py7) and N-(n-nonyl)-3-methylpyridinium bromide (Py9), formed via a single step substitution reaction, for their application towards drugs delivery. Fourier-transform infrared (FT-IR) and nuclear magnetic resonance (NMR) spectroscopic methods have been employed for the characterization of these amphiphiles. Aggregation behavior of the surfactants in solution i.e. the critical micelle concentration (CMC), has been investigated by conductometric and spectrophotometric analyses. The results reveal that the amphiphiles can act as excellent surface active agents due to their low critical micelle concentration (CMC). Furthermore, the interaction of these surfactants with two anionic drugs i.e., Ketoprofen (KP, 2-(3-Benzoylphenyl)propanoic acid) and Diclofenac sodium (DF, Sodium 2-(2,6-dichloranilino) phenylacetate), has been explored below and above the CMC value using UV-visible spectroscopy. The enhanced absorption intensities of both the drugs in the presence of synthesized surfactants indicated stronger interactions between surfactants and drugs molecules.  相似文献   
78.
A new dimeric secoiridoid glycoside, trivially named oleferrugine B ( 1 ), has been isolated from the AcOEt‐soluble part of the MeOH extract of leaves of Olea ferruginea Royle . The structure of the isolated compound was established on the basis of ESI‐MS fragmentation patterns, and 1D‐ and 2D‐NMR techniques, including 1H‐ and 13C‐NMR, HSQC, 1H,1H‐COSY, HMBC, and NOESY experiments, and by comparison with literature data.  相似文献   
79.
Iron nanoparticles of various sizes have been synthesized using the chemical route which involves the preparation of iron bipyridine complexes in presence of different capping agents followed by thermal decomposition at 450°C in inert atmosphere. The bimetallic nanoalloys of Fe with Mg and Pd have also been prepared by following the same route. The resulting nanoparticles have been characterized by EDX-RF, XRD, AFM and 57Fe Mössbauer spectroscopy. The appearance of quadrupole doublets in the Mössbauer spectra of Fe nanoparticles indicates the absence of magnetic interaction and variation in parameters is due to the varying particle size. The Mössbauer spectrum of Fe–Mg2 bimetallic nanoalloy shows two doublets indicating the presence of superparamagnetism. The two doublets can be attributed to change in s-electron density of iron resulting from its two neighboring magnesium atoms. Fe–Pd nanoalloy Mössbauer spectrum is characterized by having a superparamagnetic doublet and a ferromagnetic sextet.  相似文献   
80.
ABSTRACT

In this paper some new classes of two-variable orthogonal functions by using Fourier transforms of two-variable orthogonal polynomials are introduced. Orthogonality relations are obtained by using the Parseval identity. Recurrence relations for new families of orthogonal functions are also presented.  相似文献   
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