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101.
The development of well-organized and low-priced photoelectrocatalysts for the clean and efficient water splitting reaction is crucial. In this context, novel nitrogen-doped graphene quantum dots (N-GQDs) with high photoluminescence and upconversion emission have been synthesized as excellent light harvester. Subsequently, ordered hierarchical TiO? nanowires were decorated with upconversion N-GQDs as a photoanode by a simple preparation method to improve the photocatalytic performance in the visible and near-infrared (NIR) regions of solar light, not otherwise absorbable by bare TiO? nanostructures. Moreover, the enhancement of charge transfer efficiency and electron–hole separation according to the energy states of N-GQDs and TiO? are considered for the improved photocatalytic performance of water splitting. N-GQDs/TiO2 shows superior photoelectrocatalytic (PEC) performance, achieving a photocurrent density of 3.0 mA.cm?2 in 1.0 M KOH solution, which is eight times that of unmodified TiO? at an applied voltage of 1.23 V vs. RHE. The high stability and photoelectrocatalytic activity of oxygen evolution reaction in the presence of newly synthesized N-GQDs are confirmed by chronoamperometry, open-circuit potential measurement, and electrochemical impedance spectroscopy. The as-fabricated photoanode provides an increased solar light harvesting from UV–Vis to NIR due to the application of newly synthesized upconversion GQDs, which increase energy conversion with an appealing perspective. 相似文献
102.
Ionics - A simple and rapid electrochemical method developed for the detection of trace amounts of morphine (MO) at the surface of modified pencil graphite electrode (PGE) with multiwall carbon... 相似文献
103.
Recently, a new statistical mechanic-based equation of state has been proposed by Mohsen-Nia and Modarress [M. Mohsen-Nia, H. Modarress, Chem. Phys. 336 (2007) 22–26] for associating pure fluids. The new association equation of state (AEOS) was successfully applied to calculate the saturated properties of water, methanol, and ammonia. In this work, the new proposed AEOS is used to evaluate the (vapour + liquid) equilibrium (VLE) of 25 associating pure compounds and the adjusted parameters are reported. The new AEOS is also extended to mixtures containing associating and non-associating compounds. The calculated saturated properties of the pure compounds are compared with those calculated by other AEOSs. The results of VLE calculation for various binary mixtures such as: alcohol/hydrocarbon, alcohol/CO2, alcohol/aromatic-hydrocarbons, and the quaternary system (H2O/CH4/CO2/H2S) indicate the capability of the new proposed AEOS for associating pure and mixture calculations. 相似文献
104.
G. Rezaei Behbehani A. A. Saboury L. Barzegar O. Zarean J. Abedini M. Payehghdr 《Journal of Thermal Analysis and Calorimetry》2010,101(1):379-384
The interaction of myelin basic protein (MBP) from the bovine central nervous system with divalent nickel ion was studied
by isothermal titration calorimetry at 37 and 47 °C in Tris buffer solution at pH = 7. The new solvation model was used to
reproduce the heats of MBP + Ni2+ interaction over the whole Ni2+ concentrations. It was found that MBP has three identical and independent binding sites for Ni2+ ions. The intrinsic dissociation equilibrium constant and the molar enthalpy of binding are 89.953 μM, −14.403 kJ mol−1 and 106.978 μM, −14.026 kJ mol−1 at 37 and 47 °C, respectively. The binding parameters recovered from the new solvation model were correlated to the structural
changes of MBP due to its interaction with nickel ion interaction. It was found that in the low and high concentrations of
the nickel ions, the MBP structure was destabilized. 相似文献
105.
Zafer Mahmoud Vahab Nekoukar Mohammad Rezaei 《Mathematical and Computer Modelling of Dynamical Systems: Methods, Tools and Applications in Engineering and Related Sciences》2020,26(3):268-299
ABSTRACT 6-RSS Stewart-Gough parallel manipulator contains six crank-rod limbs connecting the base and moving platforms to each other, forming a 6DOF manipulator. In this paper, we introduce a novel decoupled inverse dynamic model for this manipulator based on the Force Distribution Algorithm. The performance of the proposed model was evaluated in tracking a complex trajectory (of multiple segments with simultaneous translational and rotational motions) using feedback-linearization control in the joint space and compared with that of the Lagrangian inverse dynamic model. Results showed that this model leads to a better performance in feedback-linearization control, especially when the reference trajectory is quantized, and with less calculation burden in comparison with the Lagrangian model. The control system employing both models showed robustness against payload uncertainty on the moving platform (150% of the moving platform’s mass). The performance assessment and the robustness approval were performed in simulation using a Simscape model specifically built for this purpose in the Simulink environment. 相似文献
106.
Shahram Rezaei 《Archiv der Mathematik》2018,110(6):563-572
Let R be a commutative Noetherian ring, \({\mathfrak {a}}\) an ideal of R, M a finitely generated R-module, and \({\mathcal {S}}\) a Serre subcategory of the category of R-modules. We introduce the concept of \({\mathcal {S}}\)-minimax R-modules and the notion of the \({\mathcal {S}}\)-finiteness dimension and we will prove that: (i) If \({\text {H}}_{\mathfrak {a}}^{0}(M), \cdots ,{\text {H}}_{\mathfrak {a}}^{n-1}(M)\) are \({\mathcal {S}}\)-minimax, then the set \(\lbrace \mathfrak {p}\in {\text {Ass}}_R( {\text {H}}_{\mathfrak {a}}^{n}(M)) \vert R/\mathfrak {p}\notin {\mathcal {S}}\rbrace \) is finite. This generalizes the main results of Brodmann–Lashgari (Proc Am Math Soc 128(10):2851–2853, 2000), Quy (Proc Am Math Soc 138:1965–1968, 2010), Bahmanpour–Naghipour (Proc Math Soc 136:2359–2363, 2008), Asadollahi–Naghipour (Commun Algebra 43:953–958, 2015), and Mehrvarz et al. (Commun Algebra 43:4860–4872, 2015). (ii) If \({\mathcal {S}}\) satisfies the condition \(C_{\mathfrak {a}}\), then This is a formulation of Faltings’ Local-global principle for the \({\mathcal {S}}\)-minimax local cohomology modules. (iii) \( \sup \lbrace i\in {\mathbb {N}}_{0} \vert {\text {H}}_{\mathfrak {a}}^{i}(M) \text { is not } {\mathcal {S}}\text {-minimax} \rbrace = \sup \lbrace i\in {\mathbb {N}}_{0} \vert {\text {H}}_{\mathfrak {a}}^{i}(M) \text { is not in } {\mathcal {S}} \rbrace \).
相似文献
$$\begin{aligned} f_{\mathfrak {a}}^{{\mathcal {S}}}(M):=\inf \lbrace f_{\mathfrak {a}R_{\mathfrak {p}}}(M_{\mathfrak {p}}) \vert \mathfrak {p}\in {\text {Supp}}_R(M/ \mathfrak {a}M) \text { and } R/\mathfrak {p}\notin {\mathcal {S}} \rbrace \end{aligned}$$
$$\begin{aligned} f_{\mathfrak {a}}^{{\mathcal {S}}}(M)= \inf \lbrace i\in {\mathbb {N}}_{0} \vert {\text {H}}_{\mathfrak {a}}^{i}(M) \text { is not } {\mathcal {S}}\hbox {-}minimax\rbrace . \end{aligned}$$
107.
Shahram Rezaei 《印度理论与应用数学杂志》2018,49(3):383-396
We prove some results concerning minimaxness and finiteness of local homology modules and by Matlis duality we extend some results for the minimaxness and finiteness of local cohomology modules. We introduce the concept of C-minimax R-modules, and we discuss the maximum and minimum integers such that local homology and local cohomology modules are C-minimax. As a consequence, we find minimum integers such that local homology and local cohomology modules are of finite length. 相似文献
108.
Kamal Alizadeh Behrooz Rezaei Bozorgmehr Maddah 《Central European Journal of Chemistry》2010,8(2):392-395
The two successive steps acidity constants of three azo dye derivatives D1–D3, were determined by a spectrophotometric method
using 0.10 M KNO3 as supporting electrolyte in water solvent. The electronic spectra of the compounds were recorded in the course of their
pH-metric titration with a standard base solution. The protolytic equilibrium constants can be solved very satisfactorily
from absorbance data, by combining the data obtained in the spectrometric determinations with graphic methods as the absorbance
diagrams. An A-diagram shows the relative absorbance changes at two wavelengths as a function of the pH. For a one-step system,
the absorbance at any wavelength must be proportional to the absorbance at any other wavelength, so an A-diagram for all wavelength
combinations for such a system must be linear (rank, s=1). However, if a system is governed by two or more equilibria, the
A-diagrams corresponding to multi-step titrations will change direction every time a new equilibrium becomes dominant in the
system. Analysis of the each uniform sub-region can then be used in evaluating of the corresponding equilibrium. A-diagrams
for all wavelength combinations suggest that these systems have the rank two(s=2). The results revealed that the Ka(1) and Ka(2) values of different azo dyes follow the order D3>D2>D1.
相似文献
109.
Various aryl aldehydes underwent prompt one pot conversion into the corresponding nitriles in high yields by reacting with hydroxylamine hydrochloride supported on melamine formaldehyde under microwave irradiation in the presence of ammonium acetate as catalyst. 相似文献
110.
On the supercyclicity and hypercyclicity of the operator algebra 总被引:1,自引:0,他引:1
Let B(X) be the operator algebra for a separable infinite dimensional Hilbert space H, endowed with the strong operator topology or *-strong topology. We give sufficient conditions for a continuous linear mapping L : B(X) →B(X) to be supercyclic or ,-supercyclic. In particular our condition implies the existence of an infinite dimensional subspace of supercyclic vectors for a mapping T on H. Hypercyclicity of the operator algebra with strong operator topology was studied' by Chan and here we obtain an analogous result in the case of *-strong operator topology. 相似文献