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排序方式: 共有502条查询结果,搜索用时 15 毫秒
71.
The electrocatalytic reduction of hydrogen peroxide (H2O2) has been studied at nanostructured copper (Cunano) modified glassy carbon (GC/Cunano) electrode in phosphate buffer (pH 7.2). The electrical properties of GC/Cunano modified electrodes were studied by electrochemical impedance spectroscopy (EIS). Surface and electrochemical characterization
were carried out by using atomic force microscopy (AFM) and cyclic voltammetry. A well-defined H2O2 reduction signal, which is due to mediation of a surface active site redox transition exhibits at the GC/Cunano electrode. The Cunano is acting as a bridge without the aid of any other electron mediator, which enables the direct electron transfer between
the modified electrode and the substrate. The results are compared with bulk copper macroelectrode and emphasized the efficiency
of the Cunano modified electrode. Systematic investigations were made to optimize the experimental parameter, such as applied potential
(Eapp) for copper electrodeposition. The calibration curve obtained from chronoamperometric studies was found to be linear in the
range 0.5 to 8.0 μM H2O2 with a detection limit of ca.10 nM (S/N = 3) at the GC/Cunano electrode. The modified electrode is stable for 1 week in phosphate buffer after repetitive measurements. 相似文献
72.
Gloves are one of the most important items in the protective ensemble as they protect hand which is the most frequently burned body part. At present, no international standard or standardized test method is available for analyzing thermal protective performance of gloves exposed to purely radiant heat exposures. In the present work, a systematic approach for developing test setup for radiant heat exposure is proposed using computational fluid dynamics (CFD). A coupled CFD–radiation heat transfer model is first developed and validated with available experimental data. Effects of horizontal and vertical orientations of radiant heaters are then analyzed. Based on this study, an optimized configuration of the experimental setup which results in uniform heat flux distribution throughout the hand under lower level of radiant heat exposure is proposed. Furthermore, effects of different heater temperatures on heat flux distribution are studied. It is found that the proposed configuration works satisfactorily for other higher and lower heat flux levels as well. 相似文献
73.
K.R. Acchutharaman N. Santhosh R. Isaac Daniel Muthu Senthil Pandian P. Ramasamy 《Ceramics International》2021,47(15):21263-21270
Titanium dioxide (TiO2) nanoparticles (NPs) were synthesized through solvothermal route by changing the rate of hydrolysis in the catalytic process. In order to change the hydrolysis rate, the concentration of acetic acid, as additive, was varied as 2 M, 3 M and 4 M. The synthesized NPs were examined by various physico-chemical characterization techniques. The powder X-ray diffraction (PXRD) analysis of the NPs reveals only the anatase phase of TiO2. The spherical shaped morphology of the NPs was observed in the high-resolution transmission electron microscopy (HR-TEM) analysis. The optical behaviour such as absorption, bandgap, diffuse reflectance and photoluminescence (PL) emission of the NPs were studied. The material's nature and behaviors were scrutinized and they were employed as photoanode in dye sensitized solar cell (DSSC) and as electron transport layer (ETL) in carbon-based perovskite solar cell (C-PSC). The charge transfer at the interface of the devices was studied with electrochemical impedance spectroscopy (EIS). The fabricated DSSC and C-PSC show highest power conversion efficiency (PCE) of 6.1% and 10.6%, respectively. The highest current collection was detected in C-PSC and the results are discussed in detail. 相似文献
74.
This study deals with the effect of electric force and magnetohydrodynamics (MHD) of the transient state on natural convection flow past an oscillating vertical plate. In addition to this, thermal radiation and porous media are also examined in the Casson fluid flow. The Poisson-Boltzmann equation is employed to show the electric potential character within the fluid region, which is put into a linear form by the implementation of Debye–Hückel linearization. It is possible to compute the precise solution to the governing equations using the Laplace transform approach. The expression of fluid velocity, fluid concentration, and temperature are exposed graphically, and numerical results for Nusselt and Sherwood numbers are also derived for vital pertinent flow constraints. Increasing electroosmosis parameters strongly boosts fluid velocity. The nonnegative values of the Helmholtz–Smoluchowski velocity highly induce the axial velocity and the negative value decelerates. With increasing radiation strength and Prandtl number, the fluid's temperature distribution diminishes. These more intricate electrokinetic rheological flows associated with electroosmotic separators, such as biomedical absorbers, are illuminated by these models. 相似文献
75.
This paper elucidates Common Mode Voltage (CMV) reduction in transformerless 3-phase 3-level Coupled Inductor Neutral Point (CI-NPC) Clamped Inverter with Hybrid Energy System. The three dimensional Space Vector Pulse Width Modulation (3D-SVPWM) with Nearest State Vector (NSV) is implemented to reduce the CMV by proper selection of medium, large and small vectors in 3D cubic space region. This NSV scheme in addition to CMV reduction, reduces the capacitor voltage balancing issues and minimizes switching losses. The proposed control provides full utilization of dc link voltage with reduced harmonics. This 3-level CI-NPC inverter is energized by hybrid energy source which includes photovoltaic system and wind energy system. The results obtained for the proposed scheme through simulation and experimental setup is compared with the conventional 2D-SVPWM and 3D-SVPWM scheme. From the compared results it is evident that the proposed scheme reduces CMV to a larger extent than 2D and 3D-SVPWM control. The simulation and experimental results are verified using matlab-simulink and FPGA-Spartan-6 controller respectively. 相似文献
76.
Govindaraj Ramasamy Jorge F. Valenzuela 《International Journal of Flexible Manufacturing Systems》2006,18(2):99-119
In this paper, a 2-OPT based procedure is proposed to solve the test-sequencing problem in a serial inspection process. Applications
of these methods are also extended to quiz problems with precedence constraints. Test problems are run on both the heuristic
and the branch and bound methods and the results are reported. An optimal test sequence is found for a real world application,
a radio inspection process, using data obtained from a high volume electronics manufacturer. 相似文献
77.
Sawant Jitendra P. Rajput Rekha Patil Seema Ryu Jungho Patil Deepak Rajaram Kale Rohidas B. 《Journal of Materials Science: Materials in Electronics》2021,32(18):22803-22812
Journal of Materials Science: Materials in Electronics - We report the hydrothermal synthesis of visible light absorbing and direct energy bandgap kesterite-structured Cu2ZnSnS4 (CZTS)... 相似文献
78.
Santhosh N. Acchutharaman K. R. Daniel R. Isaac Pandian M. Senthil Ramasamy P. 《Journal of Materials Science: Materials in Electronics》2022,33(18):14370-14380
Journal of Materials Science: Materials in Electronics - The substitution with mixed cation in perovskite has advantages in improving the overall performance and stability of the perovskite solar... 相似文献
79.
80.
Gunhyu Bae Yoo Sang Jeon Min Jun Ko Yuri Kim Seong-Beom Han Ramar Thangam Wonsik Kim Hee Joon Jung Sungkyu Lee Hyojun Choi Sunhong Min Hyunsik Hong Sangwoo Park Seong Yeol Kim Kapil D. Patel Na Li Jeong Eun Shin Bum Chul Park Hyeon Su Park Jun Hwan Moon Yu Jin Kim Uday Kumar Sukumar Jae-Jun Song Soo Young Kim Seung-Ho Yu Yun Chan Kang Steve Park Seung Min Han Dong-Hwee Kim Ki-Bum Lee Qiang Wei Liming Bian Ramasamy Paulmurugan Young Keun Kim Heemin Kang 《Advanced functional materials》2021,31(37):2103409
Developing materials with the capability of changing their innate features can help to unravel direct interactions between cells and ligand-displaying features. This study demonstrates the grafting of magnetic nanohelices displaying cell-adhesive Arg-Gly-Asp (RGD) ligand partly to a material surface. These enable nanoscale control of rapid winding (“W”) and unwinding (“UW”) of their nongrafted portion, such as directional changes in nanohelix unwinding (lower, middle, and upper directions) by changing the position of a permanent magnet while keeping the ligand-conjugated nanohelix surface area constant. The unwinding (“UW”) setting cytocompatibility facilitates direct integrin recruitment onto the ligand-conjugated nanohelix to mediate the development of paxillin adhesion assemblies of macrophages that stimulate M2 polarization using glass and silicon substrates for in vitro and in vivo settings, respectively, at a single cell level. Real time and in vivo imaging are demonstrated that nanohelices exhibit reversible unwinding, winding, and unwinding settings, which modulate time-resolved adhesion and polarization of macrophages. It is envisaged that this remote, reversible, and cytocompatible control can help to elucidate molecular-level cell–material interactions that modulate regenerative/anti-inflammatory immune responses to implants. 相似文献