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151.
152.
Tang Guangxian Shafee Ahmad Nam Nguyen Dang Tlili Iskander 《Journal of Thermal Analysis and Calorimetry》2021,143(6):4249-4260
Journal of Thermal Analysis and Calorimetry - Electrical sensor has been considered in the current attempt. Combination of buoyancy, electric and radiative forces has been included in the governing... 相似文献
153.
In this paper, we investigate the complete moment convergence for dependent linear processes with random coefficients to form 相似文献
154.
Nonlinear Dynamics - This paper presents some dynamical and operational performance of shunt and permanent-magnet DC motors powered by lead–acid batteries for water pumping applications.... 相似文献
155.
Mahboubeh Ghasemian Dazmiri Heshmatollah Alinezhad Zinatossadat Hossaini Ahmad R. Bekhradnia 《应用有机金属化学》2020,34(9):e5731
In this research, Fe3O4/ZnO magnetic core-shell nanoparticles (Fe3O4/ZnO MCNPs) were synthesized through a green method using Petasites hybridus rhizome water extract as a reducing and stabilizing agent. The morphology and size of the Fe3O4/ZnO MCNPs was identified by X-ray diffraction, scanning electron microscopy, and Energy-dispersive X-ray spectroscopy (EDX) analysis. The catalytic activity of the Fe3O4/ZnO MCNPs was evaluated in the efficient and green preparation of pyran derivatives in excellent yield using three-component reactions of dimedone, aldehydes, and malononitrile in ethanol at room temperature. The ability of some synthesized compounds to scavenge the 2,2-diphenyl-1-picrylhydrazyl radical was measured and the results proved this observation. Moreover, the antimicrobial activity of some synthesized compounds was proved by employing the disk diffusion test on Gram-positive and Gram-negative bacteria. The results for the disk diffusion test showed that compounds ( 4c, 4d, 4f and 4g ) prevented bacterial growth. 相似文献
156.
Synthesis,characterization and application of 3‐methyl‐1‐sulfonic acid imidazolium tetrachloroferrate as nanostructured catalyst for the tandem reaction of β‐naphthol with aromatic aldehydes and amide derivatives
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Ardeshir Khazaei Ahmad Reza Moosavi‐Zare Saeed Firoozmand Mohammad Reza Khodadadian 《应用有机金属化学》2018,32(2)
3‐methyl‐1‐sulfonic acid imidazolium tetrachloroferrate {[Msim]FeCl4} was prepared and fully characterized by fourier transform infrared spectroscopy (FT‐IR), X‐ray diffraction (XRD), thermal gravimetric analysis (TGA), differential thermal gravimetric (DTG), field emission scanning electron microscopy (FESEM), energy dispersive X‐ray analysis (EDX) and vibrating sample magnetometer (VSM) and used, as an efficient catalyst, for the tandem reaction of β‐naphthol with aromatic aldehydes and benzamide at 110 °C under solvent‐free conditions to give 1‐amidoalkyl‐2‐naphthols in high yields and very short reaction times. 相似文献
157.
158.
Guan-Yeow Yeap Elango Hrishikesan Yi-Huan Chan Wan Ahmad Kamil Mahmood 《Journal of fluorescence》2017,27(1):105-110
A new chalcone-based probe containing coumarin and naphthol at both ends has been synthesized via aldol condensation. The uniqueness of the newly derived probe can be ascribed to the presence of naphthol and coumarin units acting as binding site and signaling element, respectively. The fluorogenic behaviors toward various anions were investigated. The probe was characterized by various spectroscopic techniques and the in-depth study led to show excellent selectivity and sensitivity for fluoride ions. The hydrogen bonding thus formed with fluoride anion provides remarkable fluorometric responses. The interactions of the probe with fluoride ions were determined by fluorescence, FT-IR and NMR spectroscopic techniques. The exploratory studies by fluorescent spectral changes augur well for the naked-eye sensing applications. 相似文献
159.
Fatemeh Mirghaderi Ahmad Monshi Masoud Kasiri 《Research on Chemical Intermediates》2013,39(8):3901-3910
The preparation of glass-ionomer cements based on the composition of SiO2–Al2O3–CaO–SrO–F and evaluation of their properties is described. Cements were prepared via the sol–gel method and characterized by XRD, BET, SEM, and EDAX analysis. The effect of various concentrations of Sr on in vitro bioactivity of the glass speciments was investigated. In vitro bioactivity of the samples was evaluated by soaking them in simulated body fluid followed by structural characterization using SEM and atomic absorption analysis. A glass specimen with 0.5 mol of Sr exhibited appropriate bioactivity. 相似文献
160.
A novel set of light-responsive polyelectrolytes has been developed and studied, to control and tune surface wettability by introducing various types of substituted R head-groups of azo polyelectrolytes in self-assembled multilayer (SAMU) films. As part of a larger project to develop polymer surfaces where one can exert precise control over properties important to proteins and cells in contact, photo-reversibly, we describe here how one can tune quite reliably the contact angle of a biocompatible SAMU, containing a photo-reversible azo chromophore for eventual directed cell growth. The azo polyelectrolytes described here have different substituted R head-group pairs of shorter-ionized hydrophilic COOH and SO3H, shorter non-ionized hydrophobic H and OC2H5, and larger non-ionized hydrophobic octyl C8H17 and C8F17, and were employed as polyanions to fabricate the SAMU onto silicon substrates by using the counter-charge polycation PDAC. The prepared SAMU films were primarily characterized by measurement of their contact angles with water. The surface wetting properties of the thin films were found to be dependent on the type of substituted R-groups of the azo polyelectrolytes through their degree of ionization, size, hydrophobicity/hydrophilicity, solubility, conformation, and inter-polymeric association and intra-polymeric aggregation. All these factors appeared to be inter-related, and influenced variations in hydrophobic/hydrophilic character to different extents of aggregates/non-aggregates in solution because of solvation effects of the azo polyanions, and were thus manifested when adsorbed as thin films via the SAMU deposition process. For example, one interesting observation is significantly higher contact angles of 79° for SAMU films of larger octyl R groups of PAPEA-C8F17 and PAPEA-C8H17 than for others with contact angles of 64° observed for non-polar R-groups of OC2H5 and H. Furthermore, lower contact angle values of 59° for SAMU films with polar R-groups of COOH and SO3H relative to that of non-polar R-groups are in accordance with their expected order of the hydrophilicity or hydrophobicity. It is possible that the large octyl groups are more effective in shielding the ionic functional groups on the substrate surface, and contributed less to the water drop-molecule interactions with ionic groups of the PDAC and/or AA groups. In addition, higher hydrophobicity of the SAMU films may be due to the incorporation of bulky and hydrophobic groups in these polyelectrolytes, which can produce aggregates on the surfaces of the SAMU films. Through understanding and controlling the complex aggregation behavior of the different substituted R-groups of these azo polyelectrolytes, and hence their adsorption on substrates, it appears possible to finely tune the surface energy of these biocompatible films over a wide range, enhance the photo-switching capabilities of the SAMU films, and tailor other surface properties for the development and application of new devices in diverse areas of microfluidics, specialty coatings, sensors, and biomedical sciences. 相似文献