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81.
Let G
1 and G
2 be locally compact groups and let ω
1 and ω
2 be weight functions on G
1 and G
2, respectively. For i = 1, 2, let also C
0(G
i
, 1/ω
i
) be the algebra of all continuous complex-valued functions f on G
i
such that f/ω
i
vanish at infinity, and let H: C
0(G
1, 1/ω
1) → C
0(G
2, 1/ω
2) be a separating map; that is, a linear map such that H(f)H(g) = 0 for all f, g ∈ C
0(G
1, 1/ω
1) with fg = 0. In this paper, we study conditions under which H can be represented as a weighted composition map; i.e., H(f) = φ(f ℴ h) for all f ∈ C
0(G
1, 1/ω
1), where φ: G
2 → ℂ is a non-vanishing continuous function and h: G
2 → G
1 is a topological isomorphism. Finally, we offer a statement equivalent to that h is also a group homomorphism. 相似文献
82.
Madjid Abdeli Naghi Parvini Ahmadi Rasoul Azari Khosroshahi 《Journal of Solid State Electrochemistry》2010,14(7):1317-1324
The inhibiting behavior of Nile Blue and Indigo Carmine organic dyes on mild steel corrosion was evaluated in 1 M HCl solution,
separately, by weight loss, potentiodynamic polarization, and electrochemical impedance spectroscopy techniques. Results show
that the inhibition efficiency (%IE) increases with the increasing concentration of Indigo Carmine up to 9.65 × 10−05 M (%IE ~ 98) and Nile Blue up to 1.08 × 10−04 (%IE ~ 75–80). Good agreement was found between the results obtained from the different techniques used. Polarization curves
indicate that the inhibition of the both inhibitors is of a mixed anodic–cathodic nature, and Langmuir isotherm is found to
be an accurate isotherm describing the adsorption behavior. The inhibition mechanism of the inhibitors involves chemisorption
interaction between the inhibitor and the mild steel. The inhibition efficiency for both inhibitors decreased by the rising
temperature in the range of 25–55 °C, and these results verified the chemisorption behavior of both the inhibitors. 相似文献
83.
In this article we transform a large class of parabolic inverse problems into a nonclassical parabolic equation whose coefficients
consist of trace type functionals of the solution and its derivatives subject to some initial and boundary conditions. For
this nonclassical problem, we study finite element methods and present an immediate analysis for global superconvergence for
these problems, on basis of which we obtain a posteriori error estimators.
This research was supported in part by the Shahid Beheshti University, the National Basic Research Program of China (2007CB814906),
the National Natural Science Foundation of China (10471103 and 10771158), Social Science Foundation of the Ministry of Education
of China (Numerical methods for convertible bonds, 06JA630047), Tianjin Natural Science Foundation (07JCYBJC14300). 相似文献
84.
Wu Huawei Beni Mahdi Hashemi Moradi Iman Karimipour Arash Kalbasi Rasoul Rostami Sara 《Journal of Thermal Analysis and Calorimetry》2020,139(4):2791-2799
Journal of Thermal Analysis and Calorimetry - Steam generation is an essential process in steel production. Saturated steam is used in the cold-rolling mills of sample steel company to raise the... 相似文献
85.
Amir Sadeghi R. Khosroshahi Z. Sadeghian 《Journal of Surface Investigation: X-ray, Synchrotron and Neutron Techniques》2011,5(1):186-192
Ni and Ni-nano-TiO2 composite coatings with various amounts of TiO2 in electrolyte, on low carbon steel, have been prepared from Watts-bath using electrodeposition process. The morphological,
mechanical, corrosion and hydrogen permeation characteristics of Ni and Ni-nano-TiO2 coatings were studied and compared with each other. The results revealed that, existence of nano-TiO2 particles in Ni matrix improved the microstructure as well as microhardness, whereas increasing particle incorporation from
4.33 to 7.62 vol % concluded to microhardness enhancement. The corrosion behavior of Ni and Ni-nano-TiO2 composite coatings with various amount of particle content was studied by the anodic polarization curves in 5% H2SO4 solution at room temperature. It was seen Ni-nano-TiO2 composite coatings exhibited higher corrosion resistances comparing to pure Ni coating and corrosion protection improved
with increasing nano-TiO2 in coatings. In addition to the corrosion and engineering properties, comparison of hydrogen permeation characteristics of
the Ni coating was made with Ni-nano-TiO2 composite coating through Devanthan-Stachurski hydrogen permeation test. From the resulting data analysis, Ni-nano-TiO2 composite coating was seen not only to provide longer life under corroding media, but also reduces greatly the risk of the
substrate being exposed to hydrogen permeation when compared to electrodeposited Ni coating. 相似文献
86.
Design of a novel optical sensor for determination of trace amounts of copper by UV–visible spectrophotometry in real samples
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Eslam Pourbasheer Somayeh Morsali Zhila Azari Mohammad Ali Karimi Mohammad Reza Ganjali 《应用有机金属化学》2018,32(3)
A new optical chemical sensor is established for sensitive and selective spectrophotometric detection of copper based on the immobilization of 3‐(2‐methyl‐2,3‐dihydro‐1,3‐benzothiezol‐2‐yl)‐2H‐chromen‐2‐one on a triacetylcellulose membrane. Copper ions react with the immobilized ligand and cause an increase in the absorption of the membrane at 550 nm in universal buffer solution at pH = 6. The effects of pH, indicator concentration and reaction time on the immobilization of the ligand were studied. This optode exhibits a linear range of 7.0 × 10?7 to 1 × 10?4 mol l?1 of copper ion concentration with a limit of detection of 3.0 × 10?7 mol l?1. The response time of the newly designed optode is within 3 min. The effect of different possible interfering species was investigated and it was found that the sensor has very good selectivity. The proposed sensor benefits from advantages such as low cost, high stability, low detection limit, fast response time, reproducibility, relatively long lifetime, and good selectivity for Cu2+ ion determination among a large number of alkali, alkaline earth, transition and heavy metal ions. The sensor can readily be regenerated with thiourea solution and its response is reversible and reproducible (relative standard deviation < 1.4%). The proposed optode was applied successfully for the determination of Cu(II) in various samples. 相似文献
87.
88.
The effect of Sn dopant on crystal structure and photocatalytic behavior of nanostructured titania thin films 总被引:2,自引:0,他引:2
Behzad Koozegar Kaleji Rasoul Sarraf-Mamoory Kazuya Nakata Akira Fujishima 《Journal of Sol-Gel Science and Technology》2011,60(2):99-107
In this study, preparation of Sn doped (0–30 mol % Sn) TiO2 dip-coated thin films on glazed porcelain substrates via sol–gel process have been investigated. The effects of Sn content
on the structural, optical, and photo-catalytic properties of applied thin films have been studied by X-ray diffraction (XRD),
Raman spectroscopy, scanning electron microscopy (SEM), field emission SEM (FE-SEM), and high resolution transmission electron
microscopy (HR-TEM). Surface topography and surface chemical state of thin films were examined by atomic force microscope
(AFM) and X-ray photoelectron spectroscopy (XPS). XRD patterns showed an increase in peak intensities of the rutile crystalline
phase by increasing the Sn dopant. The prepared Sn-doped TiO2 photo-catalyst films showed optical absorption edge in the visible light area and exhibited excellent photo-catalytic ability
for degradation of methylene blue solution under UV irradiation. The result shows that doping an appropriate amount of Sn
can effectively improve the photo-catalytic activity of TiO2 thin films, and the optimum dopant amount is found to be 15 mol%. The Sn4+ dopants substituted Ti4+ in the lattice of TiO2 and increased surface oxygen vacancies and the surface hydroxyl groups. TEM results showed small increase in planar spacing
(was detected by HR-TEM caused by Sn dopants in titania based crystals). 相似文献
89.
Khalid Kiani David J. T. Hill Firas Rasoul Michael Whittaker Llewellyn Rintoul 《Journal of polymer science. Part A, Polymer chemistry》2007,45(6):1074-1083
RAFT mediated grafting of poly(t‐butyl acrylate) onto the surface of a commercial poly(ethylene‐co‐propylene), Elpro, has been carried out using initiation by 60Co γ‐radiation at 298 and 273 K. The polymerizations were in bulk monomer and using the RAFT agent 1‐phenylethyl phenyldithioacetate. The rates of homopolymerization and grafting were found to decrease with increasing RAFT agent concentration, indicating that both polymerization processes involve participation of the RAFT agent. There was good agreement between the predicted and experimental molecular weights of the homopolymer that had a narrow polydispersity. The poly(t‐butyl acrylate) grafts were hydrolyzed by trifluoroacetic acid to form poly(acrylic acid) grafts, which could either be further functionalized or used to control the surface polarity of the Elpro. ATR‐FTIR spectroscopy was used to characterize the grafts and Raman spectroscopy was used to assess the depth of the grafts. The water contact angle for the Elpro surface grafted with poly(acrylic acid) was found to be linearly dependent on the amount of the graft present. The living nature of the grafted chains was demonstrated by the addition of a second block of polystyrene. © 2006 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 45: 1074–1083, 2007 相似文献
90.
G. Pluvinage Z. Azari N. Kadi I. Dlouhý V. Kozk 《Theoretical and Applied Fracture Mechanics》1999,31(2):33
A deterministic approach is used to analyze cleavage failure near the notch root by application of a local fracture criterion. Micromechanism of fracture is assessed using finite element calculations. Two ferritic microstructures have been selected; they differ significantly in the carbide thickness as the fracture data scattered widely. Local damage zones are calculated from the normal stress distributions and compared with those from the notch root to the location of failure initiation. To this end, the static three-point bend Charpy V-notch specimens were used. Microfractography identifies the local damage zone distances and their locations with reference to the prevailing microstructures. 相似文献