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排序方式: 共有800条查询结果,搜索用时 788 毫秒
791.
Thanh-Tung Duong Ta Quoc Tuan Dang Viet Anh Dung Nguyen Van Quy Dinh-Lam Vu Man Hoai Nam Nguyen Duc Chien Soon-Gil Yoon Anh-Tuan Le 《Current Applied Physics》2014,14(12):1607-1611
Polyaniline nanowires (PANI NWs) were deposited onto fluorine-doped tin oxide (FTO) glass substrate using the cyclic voltammetric method with aniline monomer precursor in HCl aqueous solution. The secondary oxidation peak plays an important role in polymerization of aniline monomer and the optimization of catalytic activity of PANI-based counter electrodes was achieved by controlling the number of cycles. The photovoltaic performance of the dye-sensitized solar cells (DSSCs) with PANI NWs counter electrodes (CEs) was optimized at 4th cycles, and then following parameters were obtained: Jsc = 17.2 mA cm−2, Voc = 0.71 V, FF = 59.3%, and efficiency (η) = 7.24%. While, Jsc = 14.7 mA cm−2, Voc = 0.77 V, FF = 70.6%, and efficiency (η) = 7.98% in cells with Pt CEs. The PANI NWs were attractive as an alternative CEs for the low-cost DSSCs instead of Pt. 相似文献
792.
Khai Ern Lee Imran Khan Norhashimah Morad Tjoon Tow Teng Beng Teik Poh 《Journal of solution chemistry》2013,42(1):27-43
The viscometric properties of novel magnesium electrolyte–polyacrylamide composite polymers in aqueous solutions were investigated using response surface methodology. Independent factors such as concentration of the magnesium electrolyte (magnesium chloride and magnesium hydroxide), concentration of polyacrylamide, and the solution temperature were taken into account for viscometric modeling. Experiments were carried out according to central composite design, which includes factorial, central and axial points of the factors. Solution viscosity was taken as the response variable. A polynomial model for the viscometric properties was developed using ANOVA and non-linear regression analysis, and the R2 values are 0.9995 and 0.9996 for aqueous solutions of magnesium chloride–polyacrylamide (MCPAM) and magnesium hydroxide–polyacrylamide (MHPAM) composite polymers, respectively. Two diagnostic plots have been constructed to validate the developed models for the natural logarithm of viscosity of aqueous solutions of the MCPAM and MHPAM composite polymers. The least-squares values show that the developed models are adequate for predictive purposes. TEM was used to investigate the morphological properties of MCPAM and MHPAM composite polymers. Magnesium chloride was impregnated into the polyacrylamide chain while magnesium hydroxide was just adsorbed on the surface of the polyacrylamide chain. 相似文献
793.
The effect of combined treatment of antimicrobial coatings and γ-radiation on reduction of food pathogens such as Listeria monocytogenes, Escherichia coli, and Salmonella Typhimurium was evaluated in broccoli florets. Broccoli florets were inoculated with pathogenic bacteria at 106 CFU/g. Inoculated florets were then coated with methylcellulose-based coating containing various mixtures of antimicrobial agents: organic acids (OAs) plus lactic acid bacteria metabolites (LABs), OA plus citrus extract (CE), OA plus CE plus spice mixture (SM), and OA plus rosemary extract (RE). Coated florets were irradiated with various doses (0–3.3 kGy), and microbial analyses were used to calculate the D10 value and radiosensitive relative. The coating containing OA plus CE was the most effective formulation for increasing the sensitization of Escherichia coli by 2.4 times as compared to the control without the antimicrobial coating. For Salmonella Typhimurium, coating containing OA plus LAB was the most effective formulation, increasing radiosensitivity by 2.4 times as well. All antimicrobial coatings had almost the same effect of increasing the sensitivity of Listeria monocytogenes (from 1.31 to 1.45 times) to γ-irradiation. 相似文献
794.
X-ray absorption and resonance Raman spectroscopies show that CmlA, the β-hydroxylase of the chloramphenicol biosynthetic pathway, contains a (μ-oxo)-(μ-1,3-carboxylato)diiron(III) cluster with 6-coordinate iron centers and 3 - 4 His ligands. This active site is found within a unique β-lactamase fold and is distinct from those of soluble methane monooxygenase and related enzymes that utilize a highly conserved diiron cluster with a 2-His-4-carboxylate ligand set within a 4-helix bundle motif. These structural differences may have an impact on the nature of the activated oxygen species of the reaction cycle. 相似文献
795.
A drive-free vibratory gyroscope 总被引:1,自引:0,他引:1
Computational and analytical works have shown that certain coupling schemes can lead to significant enhancements in sensitivity, accuracy, and lower costs for a wide range of sensor devices whose output and performance depends directly on the ability of individual units to generate stable limit cycle oscillations. Vibratory gyroscopes are very good candidates for this new paradigm as their accuracy and sensitivity are directly dependent on the ability of a driving signal to produce and maintain oscillations with stable amplitude, phase, and frequency. To achieve higher accuracy, we show proof of concept of a novel scheme: a drive-free coupled gyroscope system in which the coupling alone can lead to self-regulated limit cycle oscillations in the drive- and sense-axes with stable constant amplitude and phase-locking. 相似文献
796.
Pham Loi Vu 《Journal of Nonlinear Mathematical Physics》2018,25(3):399-432
The results of inverse scattering problem associated with the initial-boundary value problem (IBVP) for the Korteweg–de Vries (KdV) equation with dominant surface tension are formulated. The necessary and sufficient conditions for given functions to be the left- and right-reflection coefficients of the scattering problem are established. The time-dependence t, t > 0 of each element of the scattering matrix s(k,t) is found in respective sector of the k-spectral plane by expansion formulas which are constructed from the known initial and boundary conditions of the IBVP. Knowing the right-reflection coefficient calculated from the elements of s(k,t), we solve the Gelfand–Levitan–Marchenko (GLM) equation in the inverse problem. Then the solution of the IBVP is expressible through the solution of the GLM equation. The asymptotic behavior at infinity of time of the solution of the IBVP is shown 相似文献
797.
Shafket Rasool Quoc Viet Hoang Doan Van Vu Chang Eun Song Hang Ken Lee Sang Kyu Lee Jong-Cheol Lee Sang-Jin Moon Won Suk Shin 《Journal of Energy Chemistry》2022,(1):236-245
Design and synthesis of low bandgap(LBG) polymer donors is inevitably challenging and their processability from a non-halogenated solvent system remains a hurdle to overcome in the area of highperformance polymer solar cells(PSCs).Due to a high aggregation tendency of LBG polymers,especially diketopyrrolopyrrole(DPP)-based polymers coupled with bithiophenes in the polymer backbones,their widespread adoption in non-ha logena ted solvent-processed PSCs has been limited.Herein,a novel LBG DPP-based... 相似文献
798.
The purpose of this paper is to discuss basic results of boundary value problems of fractional differential equations (BVP-FDEs) via the concept of Caputo fractional derivative with respect to another function with the order . The existence and uniqueness results of a solution for BVP-FDEs are discussed by utilizing Banach fixed point theorem and Schaefer's fixed point theorem. We also provide new sufficient conditions to guarantee the Hyers-Ulam stability and the Hyers–Ulam–Rassias stability of BVP-FDEs. Furthermore, some concrete examples to consolidate the obtained results are also considered. 相似文献
799.
Marcel Tintelott Tom Kremers Anabel Mernitz Sven Ingebrandt Vivek Pachauri Xuan Thang Vu Uwe Schnakenberg 《Electroanalysis》2023,35(4):e202200332
A simple equivalent electrical circuit is used to obtain the physical parameters of electrical circuit elements from measured electrochemical impedance spectra. This model consists of four circuit elements with a clear physical meaning for each of the elements. Compared to complex models with multiple constant phase elements or Warburg impedances, our model is suitable for extracting physical values for important electrode parameters with low errors. The feasibility of the model was shown by investigating pure metal or polymer-coated electrodes. Here, gold electrodes were coated either with Poly(3,4-ethylenedioxythiophene):poly(styrenesulfonate) (PEDOT : PSS), Polypyrrole:poly(styrenesulfonate) (PPy : PSS), or (PEDOT/PPy) : PSS by means of electropolymerization. The model could demonstrate the ionic-electronic differences such as the ion accessibility of the differently coated electrodes. To prove the correctness of the model, the obtained results were compared to the literature. 相似文献
800.
Let Δ be a one-dimensional simplicial complex. Let be the Stanley–Reisner ideal of Δ. We prove that for all and all intermediate ideals J generated by and some minimal generators of , we have 相似文献