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排序方式: 共有556条查询结果,搜索用时 31 毫秒
71.
E. Vardaci A. Di Nitto A. Brondi G. La Rana R. Moro P. N. Nadotchy M. Trotta A. Ordine A. Boiano M. Cinausero E. Fioretto G. Prete V. Rizzi D. Shetty M. Barbui D. Fabris M. Lunardon G. Montagnoli S. Moretto G. Viesti N. Gelli F. Lucarelli G. N. Knyazheva E. M. Kozulin 《The European Physical Journal A - Hadrons and Nuclei》2010,43(2):127-130
72.
Singh PK Kumar DN 《Spectrochimica acta. Part A, Molecular and biomolecular spectroscopy》2006,64(4):853-858
A series of new coordination complexes of cobalt(II), nickel(II) and copper(II) with two new aroylhydrazones, 2-hydroxy-1-naphthaldehyde isonicotinoylhydrazone (H(2)L(1)) and 2-hydroxy-1-naphthaldehyde-2-thenoyl-hydrazone (H(2)L(2)) have been synthesized and characterized by elemental analysis, conductance measurements, magnetic susceptibility measurements, (1)H NMR spectroscopy, IR spectroscopy, electronic spectroscopy, EPR spectroscopy and thermal analysis. IR spectra suggests ligands acts as a tridentate dibasic donor coordinating through the deprotonated naphtholic oxygen atom, azomethine nitrogen atom and enolic oxygen atom. EPR and ligand field spectra suggests octahedral geometry for Co(II) and Ni(II) complexes and a square planar geometry for Cu(II) complexes. 相似文献
73.
The electrical, structural, and photoelectrochemical properties of the polymer electrolyte PEO:NaI/I2 doped with an ionic liquid 1-ethyl 3-methylimidazolium dicyanamide (EMImDCN) have been reported. Incorporation of the ionic
liquid (IL) increases the membrane homogeneity, decreased surface roughness, and enhances the short current (J
sc). Additionally, the doping of IL provides more charge carriers which enhances overall ionic conductivity (σ). The optimized
σ was found at 40 wt.% IL composition. The fabricated DSSC using this new solid electrolyte showed 1.43% efficiency at 100 mW
cm−2. 相似文献
74.
The problem under consideration is a maximization problem over a constraint set defined by a finite number of inequality and equality constraints over an arbitrary set in a reflexive Banach space. A generalization of the Kuhn-Tucker necessary conditions is developed where neither the objective function nor the constraint functions are required to be differentiable. A new constraint qualification is imposed in order to validate the optimality criteria. It is shown that this qualification is the weakest possible in the sense that it is necessary for the optimality criteria to hold at the point under investigation for all families of objective functions having a constrained local maximum at this point 相似文献
75.
Mirgender Kumar Sarvesh Dubey Pramod Kumar Tiwari S. Jit 《Current Applied Physics》2013,13(8):1778-1786
The Silicon–Germanium-on-Insulator (SGOI) and Silicon-on-Insulator (SOI) based MOS structures are spearheading the strained-Si technology. The present work compares the subthreshold characteristics of two short-channel back-gated (BG) strained-Si-on-SGOI (SSGOI) and BG strained-Si-on-Insulator (SSOI) MOSFETs, and provides some solutions to overcome the degradation in subthreshold characteristics with the unrelenting downscaling of the devices. Subthreshold behaviors of the MOS structures are based on surface potential model which is determined by solving the 2D Poisson's equation with suitable boundary conditions by evanescent mode analysis for both of the MOS structures. The closed form expressions for threshold voltage, subthreshold current and subthreshold swing have been derived for symmetrical as well as independent gate operation (IGO). In addition, the Electrostatic integrity (EI) factors for SSOI and SSGOI MOS structures have been estimated and compared with Double-Gate (DG) MOSFET. The numerical simulation results, obtained by ATLAS?, a 2D device simulator from Silvaco, have been used to assess the validity of the models. 相似文献
76.
Sawanta S. Mali Hyungjin Kim Chang Su Shim Pramod S. Patil Chang Kook Hong 《固体物理学:研究快报》2013,7(12):1050-1054
Quaternary kesterite‐type Cu2ZnSnS4 (CZTS) nanoparticles (NPs) were successfully synthesized by a single‐step solvothermal process. Semiconductor CZTS nanoparticles were obtained from ethylene glycol (EG) and CZTS precursor after solvothermal process at 180 °C for 30 h in polyvinylpyrrolidone (PVP) medium. The synthesized CZTS NPs were further annealed at 450 °C in nitrogen atmosphere and used for further characterizations. The CZTS NPs were characterized using X‐ray powder diffraction (XRD), field emission scanning electron microscopy (FESEM), micro Raman spectroscopy, high resolution transmission electron microscopy (HRTEM) and X‐ray photoelectron spectroscopy (XPS). The optical properties of the CZTS NPs were recorded by UV–vis absorption spectroscopy. The results showed that the synthesized CZTS nanoparticles are kesterite‐type CZTS, with good crystallinity and a stoichiometric composition. Moreover, the prepared nanoparticles have a size ranging from 5–7 nm and a band gap of ~1.5 eV.
77.
Rahul Singh Jaya Baghel S. Shukla B. Bhattacharya Pramod K. Singh 《Phase Transitions》2013,86(12):1237-1245
The biopolymer solid electrolyte has been synthesized and characterized. Potassium iodide (KI) has been added in polymer matrix to develop solid polymer electrolyte. Relationships between electrical, ionic transport parameter and mechanism have been studied in detail. Impedance spectroscopy reveals the detailed electrical studies and ion transport mechanism. The ion dissociation factor is compared with a measured dielectric constant at a fixed frequency. The dielectric data are calculated which support the ionic conductivity data. 相似文献
78.
Gan Z Kwak HT Bird M Cross T Gor'kov P Brey W Shetty K 《Journal of magnetic resonance (San Diego, Calif. : 1997)》2008,191(1):135-140
Resistive and resistive-superconducting hybrid magnets can generate dc magnetic fields much higher than conventional superconducting NMR magnets but the field spatial homogeneity and temporal stability are usually not sufficient for high-resolution NMR experiments. Hardware and technique development addressing these issues are presented for high-resolution NMR at magnetic fields up to 40T. Passive ferromagnetic shimming and magic-angle spinning are used effectively to reduce the broadening from inhomogeneous magnetic field. A phase correction technique based on simultaneous heteronuclear detection is developed to compensate magnetic field fluctuations to achieve high spectral resolution. 相似文献
79.
Kavitha Kotthireddy Srikrishna Devulapally Pramod Kumar Dubey Aparna Pasula 《Journal of heterocyclic chemistry》2019,56(3):938-946
A facile, convenient, and adequate method has been developed for the synthesis of novel 5‐amino‐3‐(2‐oxo‐2H‐chromen‐3‐yl)‐7‐aryl‐7H‐thiazolo[3,2‐a]pyridine‐6,8‐dicarbonitriles ( 6 ) by employing 2‐(4‐(2‐oxo‐2H‐chromen‐3‐yl)thiazol‐2‐yl)acetonitrile ( 3 ) as an important precursor. Initially, we have synthesized the target compounds in a stepwise manner and then approached a tandem method to examine the feasibility of one‐pot method. Subsequently, one‐pot three‐component protocol has been established for the synthesis of title compounds by the reaction of 3 with benzaldehyde and malononitrile in refluxing ethanol engender a new six‐membered thiazolo[3,2‐a] pyridine as a hybrid scaffold. Reaction conditions were optimized for this reaction and a broad substrate scope with various aryl and heteroaryl aldehydes make this protocol very practical, attractive, and worthy. Mechanistic aspects for the formation of these compounds were outlined comprehensively. Characterization of these newly synthesized compounds was achieved by means of IR, 1H NMR, 13C NMR, and HRMS. 相似文献
80.
Mahesh B. Muluk Sambhaji T. Dhumal Pramod S. Phatak Naziya N. M. A. Rehman Prashant P. Dixit Prafulla B. Choudhari Ramrao A. Mane Kishan P. Haval 《Journal of heterocyclic chemistry》2019,56(9):2411-2418
In the present study, substituted formylnaphthalenyloxymethyl‐triazolyl‐N‐phenylacetamide derivatives ( 6a – k ) have been designed and synthesized employing click chemistry approach and evaluated for their in vitro antifungal and antibacterial activities. All the newly synthesized compounds were thoroughly characterized by 1H NMR, 13C NMR, and HRMS spectral techniques. Among the screened compounds, 6d , 6e , 6j , and 6k have shown good antifungal and antibacterial activities. Compound 6k has shown very effective antimicrobial activity. We further performed exploratory docking studies on microbial DNA gyrase to rationalize the in vitro biological data and to demonstrate the mechanism of antimicrobial activity. This is the first report to demonstrate the formylnaphthalenyloxymethyl, triazole, and N‐phenylacetamide hybrids as potential antimicrobial agents. 相似文献