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1.
In this paper, we obtain coupled fixed point results on complex partial metric space under contractive condition. An example to support our result is presented.  相似文献   
2.
A new phase in the MnII–SeIV–MoVI–O system, Mn(MoO3)(SeO3)(H2O) (1), has been hydrothermally synthesized with a high yield (82%), and characterized by IR, TG-DSC, magnetism measurement and single crystal X-ray diffraction. The structure of Mn(MoO3)(SeO3)(H2O) features a complicated 3D network composed of the 1D molybdenum(VI) oxide chains and the 1D manganese(II) selenite chains interconnected via Se–O–Mo and Mn–O–Mo bridges. It is stable up to approximately 340 °C, and losses water molecule at 340 °C, then release SeO2 at about 420 °C. The result of magnetic property measurements has indicated that there exist antiferromagnetic interactions between Mn(II) centers. Photocatalysis experimental result illustrates that the compound exhibits good photocatalytic performance for degradation of RhB under visible light irradiation.  相似文献   
3.
《Polyhedron》2005,24(16-17):2557-2561
The single-crystal X-ray structure of the single-molecule magnet [Mn12O12(O2CC6H4-2-CH3)16(H2O)4] · CH2Cl2 · 2H2O (complex 1) is reported. Complex 1 is a new example of a “Jahn–Teller isomer”, since it has two Mn(III) ions with abnormally oriented Jahn–Teller elongation axes. Complex 1 has a lower activation energy (Ueff = 29 K) for magnetization reversal relative to other reported [Mn12O12] type molecules (e.g., Ueff = 70 K for Mn12Ac). Single-crystal low temperature magnetization measurements are reported that confirm that complex 1 is a single-molecule magnet. High-field electron paramagnetic resonance measurements were performed on a single crystal to give the spin Hamiltonian parameters.  相似文献   
4.
Woodfordia fruticosa (L.) Kurz is a widely used plant in traditional medicine systems. The tribal communities of Amarkantak, Madhya Pradesh (India) are using this plant for the treatment of general weakness, blood related complications like blood deficiency, blood purification and for the treatment of symptoms related to sickle cell disease (SCD). SCD is a genetic disease with life threatening complications. In the absence of any drugs without any side effects, the alternative plant based therapies that may either reduce/ reverse the sickling of the red blood cells can be safe and effective therapeutic agents. We evaluated W. fruticosa extracts for phytoconstituents, anti-oxidant and anti-inflammatory properties. Anti-sickling properties of the extracts were evaluated by estimation of reverse sickling, polymerization inhibition and osmotic fragility assays. Chemical profiling of the methanol extract was done using LC-MS analysis. Phytochemicals such as alkaloids, steroids, tannin, and saponins were present in all the extracts. Methanol extract displayed maximum reversal (66 ± 1%) of sickled Red blood Cells (RBC) and significantly inhibited Hb polymerization. The hexane and methanol extracts led to minimum hemolysis of sickled RBC in the osmotic fragility assays. Total tannin (365 ± 2.4 TAE) content was highest in acetone extract, while the total flavonoid and phenolic content (156.9 ± 2.0 QE) and (113.7 ± 0.7 GAE) were highest in methanol extract. The methanol extract displayed minimum IC50 (8.1 ± 1.5) in 2, 2-diphenylpicrylhydrazyl (DPPH) while the acetone extract had minimum IC50 (215.8 ± 5.7) in 2,2′-azino-bis 3-ethylbenzothiazoline-6-sulfonic acid (ABTS) assay. The hexane extract displayed maximum Ferric reducing anti-oxidant power (FRAP) value (1.5 ± 0.5 mM Fe(II)/mg dry weight) that were higher than methanol and aqueous extracts (1.45 ± 0.1, 1.45 ± 0.05 mM Fe(II)/mg dry weight). The methanol extract provided maximum RBC protection from hemolysis (73.8 ± 0.8%). Maximum Lipoxygenase (LOX) inhibition was observed by the acetone and methanol extracts at 400 μg/mL while the hexane extract displayed maximum Xanthine oxidase (XO) inhibition (57.0 ± 0.5%). LC-MS profiling of the methanol extract identified several secondary metabolites that might be responsible for the observed activities. The results validate the traditional use of W. fruticosa and present us with potential compounds for further development of novel anti sickling agents.  相似文献   
5.
6.
Russian Journal of Organic Chemistry - A dicarboxylate-based fluorescent receptor has been synthesized for the recognition of the guanidinium ion and guanidine-containing biomolecules in aqueous...  相似文献   
7.
Abstract

In the present paper, we discuss the approximation properties of Durrmeyer-Stancu type variant of Jain operators with the modified forms of the Beta basis functions. We establish some direct results, which include the asymptotic formula, the error estimation in terms of the modulus of continuity and weighted approximation. Also, we construct a King modification of these operators which preserves the test functions e0 and e1.  相似文献   
8.
Plant extracts are one of the best possible sources of bioactive molecules, and are being used globally as an antioxidants and natural antimicrobial compounds. In current study, Schefflera vinosa leaves extract was prepared through Soxhlet extraction procedure using methanol and chloroform as solvents. The extract was investigated for total antioxidant, phenolic and flavonoid contents, free radical scavenging and antimicrobial activities. The free radical scavenging activities were evaluated through 2,2- diphenyl-1-picrylhydrazyl (DPPH), 2,2′-azino-bis-3-ethylbenzotiazolin-6-sulfonic acid (ABTS) and Ferric-reducing/ antioxidant power (FRAP) assay. The antimicrobial activity of extract was determined through poisoned food method. The methanolic extract has exhibited high antioxidant, phenolic, and flavonoid activities compared to chloroform extract. Similarly, free radical scavenging activities (ABTS, DPPH and FRAP) were higher in methanolic extract. Further, Fourier-Transform Infrared Spectroscopy (FTIR) used to determine the functional group and Gas chromatography-mass spectrometry (GC–MS) to elucidate volatile composition of the crude extract. Different functional group like N-H, O-H, C-O, C-N, C-H, C=O, C≡C and C-O-H presence indicate the existence of many metabolites in the extracts. GC–MS study identified 61 compounds and subsequently, these molecules were screened virtually using DockThor. Furthermore, antimicrobial study was confirmed against rice pathogens like Magnaporthe oryzae (M. oryzae) and Xanthomonas oryzae pv. oryzae (Xoo). Molecular docking study further suggested that phytomolecules (3-Isopropoxy-1,1,1,7,7,7-hexamethyl-3,5,5-tris (trimethylsiloxy) tetrasiloxane, and 2-Methoxy-5-methylthiophene) targets Histone Deacetylase (HDAC) of M. oryzae and Peptide Deformylase (PDF) of Xoo, which could inhibit their growth. Hence, this study indicated that Schefflera vinosa extracts could be an important ingredient as an antioxidant as well as antimicrobial agent against rice pathogens.  相似文献   
9.
《Current Applied Physics》2014,14(6):905-908
Monodisperse indium oxide (In2O3) nanoparticles (NPs) with the average diameter of 11 nm were prepared by a solvothermal method. The In2O3 NPs were characterized by X-ray diffraction, Raman and transmission electron microscopy. The intrinsic nature of ferromagnetism in In2O3 NPs has been established with the experimental observation of magnetic hysteresis loop. Photoluminescence and UV–visible studies were employed to evidence the presence of oxygen vacancies and revealed that the oxygen vacancies contribute to the ferromagnetism. The origin of ferromagnetism in In2O3 NPs may be due to exchange interactions among localized electron spin moments resulting from oxygen vacancies.  相似文献   
10.
《Polyhedron》2003,22(14-17):2375-2380
Iron (II), cobalt (II) and nickel (II) complexes of 2,6-bis(pyrazol-3-yl)pyridine (bpp) with [Cr(C2O4)3]3− have been prepared. They were characterised by single-crystal X-ray diffraction, magnetic susceptibility measurements and thermal gravimetric analyses. All three compounds are isostructural and they are formed by isolated [MII(bpp)2]2+ and [Cr(C2O4)3]3− complexes and free ClO4 . As expected, only the salt [Fe(bpp)2]2[Cr(C2O4)3]ClO4·5H2O shows a thermal spin transition with transition temperature (T1/2) around 375 K that is correlated to the loss of water molecules.  相似文献   
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