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41.
In this paper, the Moufang-Klingenberg plane over a local alternative ring R of dual numbers is studied. It is shown that its collineation group is transitive on quadrangles. It is therefore shown that
the coordinatization of these Moufang-Klingenberg planes is independent of the choice of the coordinatization quadrangle.
Also, the concept of 6-figures is extended to these Moufang-Klingenberg planes and it is shown that any 6-figure corresponds
to only one inversible m ∈ R. 相似文献
42.
Tomo T Allakhverdiev SI Mimuro M 《Journal of photochemistry and photobiology. B, Biology》2011,104(1-2):333-340
This mini review presents current topics of discussion about photosystem (PS) I and PS II of photosynthesis in the Acaryochloris marina. A. marina is a photosynthetic cyanobacterium in which chlorophyll (Chl) d is the major antenna pigment (>95%). However, Chl a is always present in a few percent. Chl d absorbs light with a wavelength up to 30 nm red-shifted from Chl a. Therefore, the chlorophyll species of the special pair in PS II has been a matter of debate because if Chl d was the special pair component, the overall energetics must be different in A. marina. The history of this field indicates that a purified sample is necessary for the reliable identification and characterization of the special pair. In view of the spectroscopic data and the redox potential of pheophytin, we discuss the nature of special pair constituents and the localization of the enigmatic Chl a. 相似文献
43.
Yekeler E Suleyman E Tunaci A Tunaci M Balci NC Onem K Tunc M Acunas G 《Magnetic resonance imaging》2004,22(9):1193-1199
Contrast-enhanced 3D MR voiding urethrography (CE 3D MRVU) was performed on 5 healthy volunteers and 18 patients with urethral disease. After intravenous injection of 0.3 ml/kg gadolinium, the images of the three consecutive acquisitions of the 3D MRVU technique were obtained during voiding. The raw data were reconstructed on all patients for visual analysis. The image quality of the volunteers was technically sufficient to demonstrate normal urethral anatomy. Contrast-enhanced 3D MR voiding urethrography of the urethral strictures was compared with conventional retrograde urethrography (n = 10) and urethroscopy (n = 12). The urethral pathologies including strictures and other obstructive causes of impaired urethral flow were correctly identified on CE 3D MRVU. 相似文献
44.
A rapid and practical solid sampling electrothermal atomic absorption spectrometric method was described for the determination of lead in scalp hair. Hair samples were washed once with acetone; thrice with distilled-deionized water and again once with acetone and dried at 75 °C. Typically 0.05 to 1.0 mg of dried samples were inserted on the platforms of solid sampling autosampler. The effects of pyrolysis temperature, atomization temperature, the amount of sample as well as addition of a modifier (Pd/Mg) and/or auxiliary digesting agents (hydrogen peroxide and nitric acid) and/or a surfactant (Triton X-100) on the recovery of lead were investigated. Hair samples were washed once with acetone; thrice with distilled-deionized water and again once with acetone and dried at 75 °C. Typically 0.05 to 1.0 mg of dried samples were inserted on the platforms of solid sampling autosampler. The limit of detection for lead (3σ, N = 10) was 0.3 ng/g The addition of modifier, acids, oxidant and surfactant hardly improved the results. Due to the risk of contamination and relatively high blank values, the lead in hair were determined directly without adding any reagent(s). Finally, the method was applied for the segmental determination of lead concentrations in hair of different persons which is important to know when and how much a person was exposed to the analyte. For this purpose, 0.5 cm of pieces were cut along the one or a few close strands and analyzed by solid sampling. 相似文献
45.
Engin?Arslan Mustafa?K.?Ozturk ?zgür?Duygulu Ali?Arslan?Kaya Suleyman?Ozcelik Ekmel?Ozbay 《Applied Physics A: Materials Science & Processing》2009,94(1):73-82
In the present paper, the effect of in-situ substrate nitridation time on crystalline quality of GaN films grown on Si (111)
substrates by metal organic chemical vapor deposition (MOCVD) were investigated. A thin buffer layer of silicon nitride (SiN
x
) with various thicknesses was achieved through the nitridation of substrate at different nitiridation times ranging from
0 to 660 s. The structural characteristics, such as dislocation densities, correlation lengths of columnar crystallites, the
tilt and twist of the mosaic structure, and the angles of rotational disorder, were all studied in detail by using a planar
and cross-sectional view of high resolution transmission electron microscopy (HRTEM) and X-ray diffraction (HRXRD) performed
at different scattering geometries. It was found that the dislocation densities, lateral coherence lengths, vertical coherence
lengths, and the tilt and twist of mosaic blocks in GaN films monotonically varies with the nitridation time. The experimental
findings showed that the nitridation times had more influence on edge dislocation densities than the screw type. 相似文献
46.
Caliskan Suleyman Yildirim Ertan Anakok Deniz Akin Cete Servet 《Journal of Solid State Electrochemistry》2022,26(2):549-557
Journal of Solid State Electrochemistry - In this study, a new amperometric biosensor for creatinine determination was developed. For this purpose, a polypyrrole-polyvinylsulfonate film was... 相似文献
47.
Cu Nanoparticles Electrodeposited at Liquid–Liquid Interfaces: A Highly Efficient Catalyst for the Hydrogen Evolution Reaction
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Emre Aslan Dr. Imren Hatay Patir Prof. Dr. Mustafa Ersoz 《Chemistry (Weinheim an der Bergstrasse, Germany)》2015,21(12):4585-4589
The electrochemical deposition of Cu nanoparticles with an average diameter of approximately 25–35 nm has been reported at liquid–liquid interfaces by using the organic‐phase electron‐donor decamethylferrocene (DMFc). The electrodeposited Cu nanoparticles display excellent catalytic activity for the hydrogen evolution reaction (HER); this is the first reported catalytic effect of Cu nanoparticles at liquid–liquid interfaces. 相似文献
48.
Kupriyanova EV Sinetova MA Markelova AG Allakhverdiev SI Los DA Pronina NA 《Journal of photochemistry and photobiology. B, Biology》2011,103(1):78-86
The gene for β-class carbonic anhydrase (CA), which was designated as cahB1, was cloned from the genomic library of the alkaliphilic cyanobacterium Microcoleus chthonoplastes. The product of the cahB1 gene was expressed in Escherichia coli. The protein revealed high specific activity of CA, which was inhibited with ethoxyzolamide. The maximum activity of the recombinant CA was detected at alkaline pH (~9.0) and its minimum - at neutral pH (~7.0). Western blotting analysis with the antibodies raised against the recombinant CahB1 protein revealed its localization in cell envelopes of M. chthonoplastes. Immunocytochemical localization of the CahB1 in cells confirmed its extracellular location. The newly characterized CahB1 of Microcoleus was similar in amino acid and nucleotide sequences to well known β-CAs of Synechococcus sp. PCC 7942 (IcfA) and Synechocystis sp. PCC 6803 (CcaA), although those CAs were attributed to the carboxysomal shells of cyanobacteria. Previously we have reported β-class CA which was associated with PS II of alkaliphilic cyanobacteria. Here we first report extracellular localization of β-class CA and provide a scheme for its possible involvement in the maintenance of a balance between external sources of inorganic carbon and photosynthesis in extreme environments of soda lakes. 相似文献
49.
Bending of an elastic annular composite plate with a light filler lying on an elastic foundation is considered. The plate
is subjected to local loads. To describe the kinematics of the package, asymmetric across its thickness, the hypotheses of
broken normal is accepted. The reaction of foundation is described based on the Winkler model. A system of equilibrium equations
is constructed, and its exact solution in displacements is found. Numerical solutions for a metal-polymer sandwich plate are
presented.
__________
Translated from Mekhanika Kompozitnykh Materialov, Vol. 43, No. 1, pp. 109–120, January–February, 2007. 相似文献
50.
Asli Baysal Suleyman Akman 《International journal of environmental analytical chemistry》2013,93(2):141-150
Abstract Several aquatic heterogeneous humic-solute fractions with known molecular-size ranges were fractionated further by coupled size-exclusion chromatography (SEC) and polyacrylamide gel electrophoresis (PAGE). The results of SEC-PAGE, obtained for several humic-solute fractions, corresponded reasonably well to the known molecular-size distributions of the dissolved organic matter (DOM). Despite the limited resolving power PAGE appears to offer an alternative coarse method, beside SEC, for fractionation of the heterogeneous humic matter (HM). 相似文献