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201.
György Bor 《Journal of organometallic chemistry》1975,94(2):181-188
The molecular structures of (C5H5)2V and (C5H5)2Cr have been determined by gas phase electron diffraction. The best agreement between calculated and experimental curves is obtained for models with eclipsed C5H5 rings (symmetry D5h), but models with staggered rings (symmetry D5d) cannot be definitely ruled out. The MC and CC bond distances are 2.169(4) and 1.431(2) Å respectively in (C5H5)2Cr, and 2.280(5) and 1.434(3) Å respectively in (C5H5)2V. The CH bonds in (C5H5)2Cr are bent 2.9(1.1)° out of the plane of the carbon atoms towards the metal atom.The molecular structures of the known di-π-cyclopentadienyl compounds of the first row transition elements are compared in the light of what is known about their electronic structures. 相似文献
202.
203.
Hüseyin Bor 《Positivity》2013,17(3):677-681
In Bor (C. R. Acad. Sci. Paris, Ser. I 346:391–394, 2008), we have proved a result dealing with $\mid {\bar{N}, p_n, \theta _{n}} \mid _{k}$ summability factors by using a quasi- $\beta $ -power increasing sequence . In this paper, that result has been generalized by using a new class of power increasing sequences , which is a wider calss of sequences, instead of a quasi- $\beta $ -power increasing sequence. Some new results have also been obtained. 相似文献
204.
Hybrid solar cells have been fabricated using perylene monoimide–monoanhydride dyes with nanorod zinc oxide electrodes as electron transporting layers. We have investigated the influence of the spacer alkyl chain length of perylene monoimide–monoanhydride (PMIMA) dyes on the device performance in hybrid solar cells using nanorod zinc oxide electrodes. Nanorod zinc oxide electrodes with 50–150 nm of diameter were synthesized in the presence of PEG400 by using microwave heating method. We observed that the dyes with longer and brunched alkyl chains exhibit higher efficiencies in hybrid solar cells. We report the highest efficiency obtained with zinc oxide nanorods under standard conditions for perylene monoimide–monoanhydride derivative with PMIMA_1 that performs 400 mV open circuit voltage, 2.81 mA/cm2 short-circuit current and 0.59% overall conversion efficiency. 相似文献
205.
Béla Hopp Tomi Smausz Bence Papdi Zsolt Bor András Szabó Lajos Kolozsvári Costas Fotakis Antal Nógrádi 《Applied Physics A: Materials Science & Processing》2008,93(1):45-49
In the production of biosensors or artificial tissues a basic step is the immobilization of living cells along the required
pattern. In this paper the ability of some promising laser-based methods to influence the interaction between cells and various
surfaces is presented.
In the first set of experiments laser-induced patterned photochemical modification of polymer foils was used to achieve guided
adherence and growth of cells to the modified areas: (a) Polytetrafluoroethylene was irradiated with ArF excimer laser (λ=193 nm, FWHM=20 ns, F=9 mJ/cm2) in presence of triethylene–tetramine liquid photoreagent; (b) a thin carbon layer was produced by KrF excimer laser (λ=248 nm, FWHM=30 ns, F=35 mJ/cm2) irradiation on polyimide surface to influence the cell adherence. It was found that the incorporation of amine groups in
the PTFE polymer chain instead of the fluorine atoms can both promote and prevent the adherence of living cells (depending
on the applied cell types) on the treated surfaces, while the laser generated carbon layer on polyimide surface did not effectively
improve adherence.
Our attempts to influence the cell adherence by morphological modifications created by ArF laser irradiation onto polyethylene–terephtalate
surface showed a surface–roughness dependence. This method was effective only when the Ra roughness parameter of the developed
structure did not exceed the 0.1 micrometer value.
Pulsed laser deposition with femtosecond KrF excimer lasers (F=2.2 J/cm2) was effectively used to deposit structured thin films from biomaterials (endothelial cell growth supplement and collagen
embedded in starch matrix) to promote the adherence and growth of cells.
These results present evidence that some surface can be successfully altered to induce guided cell growth. 相似文献
206.
Csaba Vass Károly Osvay Tamás Véső Béla Hopp Zsolt Bor 《Applied Physics A: Materials Science & Processing》2008,93(1):69-73
Submicrometer period fused silica gratings were produced by two-beam interferometric laser-induced backside wet etching technique
(TWIN LIBWE). The fourth harmonic of a Nd:YAG laser beam was spatially filtered in two steps, and the smoothened beam was
split into two parts and interfered at incident angles of 60°, 30°, 14°, and 7.7°, respectively, on the backsides of fused
silica plates that were in contact with a liquid absorber. The periods of the produced fused silica gratings were, respectively,
154 nm, 266 nm, 550 nm, and 990 nm. In the next step, TWIN-LIBWE setup was completed by using a coupling rectangular prism
in order to reach immersion setup, which made possible to fabricate 104 nm period fused silica grating. This is the smallest
laser-generated grating constant in fused silica at present.
The morphology of the etched gratings was characterized by atomic force microscope. Important parameters (modulation depth,
low-pass filtered waviness, quality factor) of the produced gratings were determined. Evolution of the grating parameters
was also studied in the 990 nm case: the dependence of modulation depth, waviness, and quality factor on the number of laser
pulses was investigated. 相似文献
207.
Behnam Ghalei Kazuki Wakimoto Chih Yi Wu Ali Pournaghshband Isfahani Takuma Yamamoto Kento Sakurai Masakazu Higuchi Bor Kae Chang Susumu Kitagawa Easan Sivaniah 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2019,131(52):19210-19216
The effect of organic ligands on the separation performance of Zr based metal–organic framework (Zr‐MOF) membranes was investigated. A series of Zr‐MOF membranes with different ligand chemistry and functionality were synthesized by an in situ solvothermal method and a coordination modulation technique. The thin supported MOF layers (ca. 1 μm) showed the crystallographic orientation and pore structure of original MOF structures. The MOF membranes show excellent selectivity towards hydrogen owing to the molecular sieving effect when the bulkier linkers were used. The molecular simulation confirmed that the constricted pore apertures of the Zr‐MOFs which were formed by the additional benzene rings lead to the decrease in the diffusivity of larger penetrants while hydrogen was not remarkably affected. The gas mixture separation factors of the MOF membranes reached to H2/CO2=26, H2/N2=13, H2/CH4=11. 相似文献
208.
O. Borůvka 《Annali di Matematica Pura ed Applicata》1956,41(1):325-342
Résumé Le présent Mémoire contient la partie analytique d'une théorie des transformations des intégrales des équations différentielles
linéaires ordinaires du second ordre. Il s'agit des équations réelles (a), (A) (p. 327) et des questions de caractère global. La théorie développée gravite autour des propriétés des équations différentielles
non-linéaires du troisième ordre (b), (B) (p. 327). Sont donnés, en particulier, les théorèmes sur l'existence et l'unicité ainsi que les expressions explicites pourles intégrales des équations (b), (B). 相似文献
209.
210.
G. Battiston G. Sbrignadello G. Bor J.A. Connor 《Journal of organometallic chemistry》1977,131(3):445-452
Under suitable conditions, the reaction of allylzinc bromide with a carbonyl compound can be reversible. 相似文献