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81.
A right module $M$ over an associative ring $R$ with unity is a $QTAG$-module if every finitely generated submodule of any homomorphic image of $M$ is a direct sum of uniserial modules. This article considers the closure of $h$-pure-$S$-high submodules of $QTAG$-modules. Here, we determine all submodules $S$ of a $QTAG$-module $M$ such that each closure of $h$-pure-$S$-high submodule of $M$ is $h$-pure-$\overline{S}$-high in $\overline{M}$. A few results of this theme give a comparison of some elementary properties of $h$-pure-$S$-high and $S$-high submodules. 相似文献
82.
The densities (ρ), viscosities (η), refractive indices (nD), and speeds of sound (u), of binary mixtures of pyridine with 1-hexanol, 1-heptanol, 1-octanol and 1-decanol, including those of pure liquids, were measured over the entire composition range at 303.15 K and atmospheric pressure. From these experimental data, the values of excess molar volumes (VE), deviations in isentropic compressibilities (Δks), viscosities (Δh), molar refractions (ΔRm), apparent and partial molar volumes (Vf,2 and ), apparent and partial molar compressibilities (Kf,2 and ), of alkanols in pyridine and their corresponding deviations (ΔV and ΔK) were calculated. The variations of these parameters with composition of the mixtures suggest that the strength of interactions in these mixtures follow the order: 1-hexanol>1-heptanol>1-octanol>1-decanol. All the excess and deviation functions were fitted to Redlich-Kister polynomial equation to determine the fitting coefficients and the standard deviations. 相似文献
83.
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
84.
May Lee Low Cheang Wei Chan Pei Ying Ng Ing Hong Ooi Mohd Jamil Maah Soi Moi Chye 《Journal of Coordination Chemistry》2017,70(2):223-241
Three ternary copper(II) complexes, [Cu(phen)(L-phe)Cl]·2H2O, [Cu(phen)(L-leu)Cl]·4½H2O, and [Cu(phen)(L-tyr)Cl]·3H2O, and four binary copper(II) complexes, [Cu(phen)Cl2], Cu(L-phe)2·½H2O, Cu(L-leu)2·½H2O, and Cu(L-tyr)2·H2O (where phen = 110-phenanthroline, L-phe = L-phenylalanine, L-tyr = L-tyrosine, L-leu = L-leucine and Cl- = chloride), were synthesized and characterized by elemental analysis, spectroscopic techniques (FTIR, UV–visible, fluorescence spectroscopy), magnetic susceptibility, molar conductivity, and lipophilicity measurement. X-ray diffraction determination of a single crystal of [Cu(phen)(L-tyr)Cl] showed two independent molecules in the asymmetric unit, each with the same distorted square pyramidal geometry about copper(II). p-Nitrosodimethylaniline assay revealed that the three ternary complexes were better inducers of reactive oxygen species over time than binary complexes, CuCl2, and free ligands. All the copper(II) complexes in this series inhibited the three proteolytic activities in the order Trypsin-like > Caspase-like > Chymotrypsin-like. In terms of anticancer properties, the copper(II)-phen complexes had GI50 values of less than 4 μM against MCF-7, HepG2, CNE1 and A549 cancer cell lines, more potent than cisplatin. 相似文献
85.
Idris Mohd Srivastava Seema Baggi Tulsidas R. Shukla Sudhir Kumar 《平面色谱法杂志一现代薄层色谱法》2010,23(5):339-342
JPC – Journal of Planar Chromatography – Modern TLC - A simple, accurate, and inexpensive high-performance thin-layer chromatography (HPTLC) method has been established for analysis of... 相似文献
86.
Mohd Rafein Zakaria Hidayah Ariffin Suraini Abd-Aziz Yoshihito Shirai 《Polymer Degradation and Stability》2010,95(8):1382-1386
Poly(3-hydroxybutyrate) [P(3HB)] homopolymer and poly(3-hydroxybutyrate-co-3-hydroxyvalerate) [P(3HB-co-3HV)] copolymer was produced by Comamonas sp. EB172 using single and mixture of carbon sources. Poly(3-hydroxyvalerate) P(3HV) incorporation in the copolymer was obtained when propionic and valeric acid was used as precursors. Incorporation of 3HV fractions in the copolymer varied from 45 to 86 mol% when initial pH of the medium was regulated. In fed-batch cultivation, organic acids derived from anaerobically treated palm oil mill effluent (POME) were shown to be suitable carbon sources for polyhydroxyalkanoate (PHA) production by Comamonas sp. EB172. Number average molecular weight (Mn) produced by the strain was in the range of 153-412 kDa with polydispersity index (Mw/Mn) in the range of 2.2-2.6, respectively. Incorporation of higher 3HV units improved the thermal stability of P(3HB-co-3HV) copolymer. Thus the newly isolated bacterium Comamonas sp. EB172 is a suitable candidate for PHA production using POME as renewable and alternative cheap raw materials. 相似文献
87.
88.
Nicolas Droushiotis Uttam Doraswami Douglas Ivey Mohd Hafiz Dzarfan Othman Kang Li Geoff Kelsall 《Electrochemistry communications》2010,12(6):792-795
A phase inversion process was used to co-extrude cerium–gadolinium oxide (Ce0.9Gd0.1O1.95)/NiO–CGO dual-layer hollow fibres (HF), which were then sintered to form, respectively, the electrolyte and high porosity anode precursor of a solid oxide fuel cell (SOFC) with anode inner diameter of 0.8 mm. Graded CGO–lanthanum strontium cobalt ferrite (La0.6Sr0.4Fe0.8Co0.2O3) cathode layers were then painted onto the CGO electrolyte to form a micro-tubular HF-SOFC. With a carefully designed anode current collector, this produced maximum power densities of 1186–5864 W m? 2 at 450–570 °C. High magnification imaging analysis revealed large three-phase boundary regions within the anode, a dense electrolyte layer and clearly highlighted the multiple CGO–LSCF cermet and pure LSCF cathode layers. The performance of the HF-SOFC with a twenty millimetre active length showed no degradation after four thermal cycles between 300 °C and 570 °C. 相似文献
89.
Mohd Marsin Sanagi Mazidatulakmam Miskam Wan Aini Wan Ibrahim Dadan Hermawan Hassan Y. Aboul‐Enein 《Journal of separation science》2010,33(14):2131-2139
A three‐phase hollow fiber liquid‐phase microextraction method coupled with CE was developed and used for the determination of partition coefficients and analysis of selected nitrophenols in water samples. The selected nitrophenols were extracted from 14 mL of aqueous solution (donor solution) with the pH adjusted to pH 3 into an organic phase (1‐octanol) immobilized in the pores of the hollow fiber and finally backextracted into 40.0 μL of the acceptor phase (NaOH) at pH 12.0 located inside the lumen of the hollow fiber. The extractions were carried out under the following optimum conditions: donor solution, 0.05 M H3PO4, pH 3.0; organic solvent, 1‐octanol; acceptor solution, 40 μL of 0.1 M NaOH, pH 12.0; agitation rate, 1050 rpm; extraction time, 15 min. Under optimized conditions, the calibration curves for the analytes were linear in the range of 0.05–0.30 mg/L with r2>0.9900 and LODs were in the range of 0.01–0.04 mg/L with RSDs of 1.25–2.32%. Excellent enrichment factors of up to 398‐folds were obtained. It was found that the partition coefficient (Ka/d) values were high for 2‐nitrophenol, 3‐nitrophenol, 4‐nitrophenol, 2,4‐dinitrophenol and 2,6‐dinitrophenol and that the individual partition coefficients (Korg/d and Ka/org) promoted efficient simultaneous extraction from the donor through the organic phase and further into the acceptor phase. The developed method was successfully applied for the analysis of water samples. 相似文献
90.
Nazim Hasan Hui-Fen Wu Yi-Hsien Li Mohd Nawaz 《Analytical and bioanalytical chemistry》2010,396(8):2909-2919
We introduce a simplified sample preparation method using bare TiO2 nanoparticles (NPs) to serve as multifunctional nanoprobes (desalting, accelerating, and affinity probes) for effective enrichment
of phosphopeptides from microwave-assisted tryptic digestion of phosphoproteins (α-casein, β-casein and milk) in Electrospray
Ionization Mass Spectrometry (ESI-MS) and Matrix Assisted Laser Desorption Ionization Mass Spectrometry (MALDI-MS). The results
demonstrate that TiO2 NPs can effectively enrich and accelerate the digestion reactions of phosphoproteins in aqueous solutions and also from complex
real samples. After the microwave experiments, we directly injected the resulting solutions into the ESI-MS and MALDI-MS systems
for analysis, and excellent sensitivity was achieved without the need for any washing procedure or separation process. The
reasons are attributed to the high binding affinity and selectivity of TiO2 NPs toward phosphopeptides. Thus, phosphopeptides can be adsorbed onto the TiO2 NP surface. The digested or partially digested phosphoproteins can be concentrated onto the TiO2 NP surface. This results in the effective or complete digestion of phosphoproteins in a short period of time (45 s). In addition,
high sensitivity and sequence coverage of phosphopeptide can be obtained using TiO2 NPs as microwave absorbers and affinity probes in MALDI-MS and ESI-MS. This is due to the photocatalytic nature of the TiO2 NPs because the absorption of microwave radiation that can accelerate the activation of trypsin for efficient digestion of
phosphoproteins and enhances the ionization of phosphopeptides. The lowest concentrations detected for ESI-MS and MALDI-MS
were 0.1 μM and 10 fmol, respectively, for α-casein. Comparing the two-step approach of TiO2 NPs with microscale TiO2 particles, the microscale TiO2 particles shows no effect on the microwave-assisted tryptic digestion of phosphoproteins. The current approach offers multiple
advantages, such as great simplicity, high sensitivity and selectivity, straightforward and separation/washing-free technique
for phosphorpeptide enrichment analysis. 相似文献