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121.
Mollah Md. Aslam Usha Rownok Jahan Tasnim Sanjida Ahmed Kawsar 《Optical and Quantum Electronics》2020,52(9):1-16
Optical and Quantum Electronics - A complex studies of optoelectronics, non-linear optical and laser stimulated piezoelectric features of chalcogenide powder-like chalcogenide crystals pure and... 相似文献
122.
Mishra A. Jahan CS A. Kesarwani S. Raval H. Kumar S. Meena J. 《The European Physical Journal A - Hadrons and Nuclei》2019,55(6):1-8
The European Physical Journal A - In this paper, we investigated the spectroscopy of heavy tetraquarks through a relativistic diquark-antidiquark model. To this aim, the two-bosonic Klein-Gordon... 相似文献
123.
Shama Sehar Iffat Naz Abdul Rehman Wuyang Sun Saleh S. Alhewairini Muhammad Nauman Zahid Adnan Younis 《应用有机金属化学》2021,35(1)
Herein, two‐shaped cerium oxide nanoparticles (NPs), that is, spherical and cubical, were synthesized through hydrothermal approach by tuning reaction temperatures. The morphology and structural and chemical composition of both samples were characterized by transmission electron microscopy (TEM), high‐resolution TEM (HRTEM), X‐ray diffraction (XRD), and X‐ray photoelectron spectroscopy (XPS), respectively. Both types of NPs were subjected to photodegradation of industrial dye, methylene blue, under dark, sunlight, and UV irradiation, and their recyclability and reusability were also assessed. Besides, the effect of pH, concentration of NPs, and dye on degradability was also analyzed. The cubical‐shaped NPs demonstrated superior degradation of ~70% under UV irradiation than the spherical ones (<50%). The antibacterial activities of both NPs were also examined, and cubical‐shaped NPs were found to exhibit superior antimicrobial potential (zone of inhibition [ZOI]: 25.75 ± 0.25, 18.83 ± 0.76, 15.75 ± 0.66, and 15.75 ± 0.25 mm) in comparison with the spherical ones (ZOI: 19.41 ± 0.94, 14.25 ± 0.66, 12.58 ± 1.01, and 9.91 ± 1.01 nm) for Escherichia coli, Pseudomonas aeruginosa, Bacillus subtilis, and Staphylococcus aureus respectively with reduced growth and viable count. This difference in performance may be attributed to the higher surface areas of cubical‐shaped NPs and higher content of oxygen vacancies. The results presented in this study suggest that cubical NPs are excellent candidates for treating industrial wastewater with greater reproducibility. Moreover, they can be used as active growth inhibitors against different microorganisms and thus can be extremely useful in developing medical devices and to design various antimicrobial systems. 相似文献
124.
Cerium(III) chloride is found to be an highly efficient catalyst for the addition of aldehydes, β-naphthol and cyclic 1,3-dicarbonyl compounds/Meldrum's acid via a multicomponent reaction. The easy availability of starting materials, novel and eco-friendly procedure makes this strategy more useful for the preparation of tetrahydrobenzo[a]-xanthen-11-one, and benzo[f]chromen-3-one derivatives. 相似文献
125.
The nonlinear propagation of the dust-acoustic bright and dark envelope solitons in an opposite polarity dusty plasma(OPDP) system(composed of non-extensive q-distributed electrons, iso-thermal ions, and positively as well as negatively charged warm dust) has been theoretically investigated. The reductive perturbation method(which is valid for a small, but finite amplitude limit) is employed to derive the nonlinear Schr¨odinger equation. Two types of modes, namely, fast and slow dust-acoustic(DA) modes, have been observed. The conditions for the modulational instability(MI) and its growth rate in the unstable regime of the DA waves are significantly modified by the effects of non-extensive electrons, dust mass, and temperatures of different plasma species, etc. The implications of the obtained results from our current investigation in space and laboratory OPDP medium are briefly discussed. 相似文献
126.
127.
As a generalization of the facet ideal of a forest, we define monomial ideal of forest type and show that monomial ideals of forest type are pretty clean. As a consequence, we show that if I is a monomial ideal of forest type in the polynomial ring S, then Stanley's decomposition conjecture holds for S/I. The other main result of this article shows that a clutter is totally balanced if and only if it has the free vertex property, and which is also equivalent to say that its edge ideal is a monomial ideal of forest type or is generated by an M sequence. 相似文献
128.
Electrocatalytically active graphene-porphyrin MOF composite for oxygen reduction reaction 总被引:1,自引:0,他引:1
Pyridine-functionalized graphene (reduced graphene oxide) can be used as a building block in the assembly of metal organic framework (MOF). By reacting the pyridine-functionalized graphene with iron-porphyrin, a graphene-metalloporphyrin MOF with enhanced catalytic activity for oxygen reduction reactions (ORR) is synthesized. The structure and electrochemical property of the hybrid MOF are investigated as a function of the weight percentage of the functionalized graphene added to the iron-porphyrin framework. The results show that the addition of pyridine-functionalized graphene changes the crystallization process of iron-porphyrin in the MOF, increases its porosity, and enhances the electrochemical charge transfer rate of iron-porphyrin. The graphene-metalloporphyrin hybrid shows facile 4-electron ORR and can be used as a promising Pt-free cathode in alkaline Direct Methanol Fuel Cell. 相似文献
129.
A novel electrode was prepared by forming TiO2 thin films using a commercially available TiO2 powder (Degussa P25) on graphite plates for water photoelectrocatalytic decontamination. In addition to, for the first time the photoelectrochemical degradation of 3,4‐dichlorophenol was investigated. The effects of applied potential, pH, and initial 3,4‐dichlorophenol concentration on the photoelectrocatalytic (PEC) degradation of 3,4‐dichlorophenol using ultraviolet (UV) illuminated TiO2/graphite (TiO2/C) thin film electrode was examined and discussed. Also, direct photolysis (DP), electrochemical oxidation (EC), photocatalytic (PC) and photoelectrocatalytic (PEC) degradation of 3,4‐dichlorophenol were compared. Results show that the best responses for PEC are obtained at applied potential 1.2 V versus reference electrode, pH 8.0 and initial 3,4‐dichlorophenol concentration 6.7 mg L?1. 相似文献
130.
Poly(o‐aminophenol) (POAP) was formed by successive cyclic voltammetry in monomer solution in the presence of sodium dodecyl sulfate (SDS) on the surface of a carbon paste electrode (CPE). Ni(II) ions were incorporated into the electrode by immersion of the polymeric modified electrode having amine groups in 0.1 M Ni(II) ion solution. Electrochemical study of this modified electrode shows a good redox behavior of the Ni(III)/Ni(II) couple. The electrocatalytic oxidations of glucose and other carbohydrates at the surface of the Ni/SDS‐POAP/CPE were studied in a 0.1 M NaOH solution. Compared to POAP/CPE, the SDS‐POAP/CPE significantly enhanced the catalytic efficiency of Ni ions for carbohydrates oxidation. Finally, using chronoamperometric method, the catalytic rate constants (k) for carbohydrates were calculated. 相似文献