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81.
N‐coordinate Pd2+ complexes [PdL2] (L: N‐N‐quinoline‐8‐yl‐R‐benzenesulfonamides) ( 6–10 ) and [PdL2] complexes assembled on multi‐wall carbon nanotubes (MWCNTs) hybrid nanomaterials were fabricated and characterized by various techniques. The [PdL2] impregnated MWCNTs materials ( 11–15 ) were applied as a counter electrode (CE) catalyst for triiodide to iodide reduction reaction in the dye‐sensitized solar cells (DSSC) and investigated electro‐catalytic activities. The MWCNTs‐supported [PdL2] CEs ( 11–15 ) are exhibits as Pt‐free CE with good power conversion efficiencies (PCEs), and compared to platinum and bare MWCNTs CEs and the PCE of bare MWCNTs was clearly improved by means of [PdL2] complexes ( 6–10 ). The DSSCs based on the hybrid counter electrodes (CEs) ( 11–15 ) and bare MWCNTs are indicated a relative efficiency ( ? rel ) of 64.27%, 54.07%, 53.75%, 51.52% 44.82% and 27.27% concerning a Pt CE control device set at 100%. The report emphasizes that [PdL2] impregnated MWCNTs type counter electrodes (CEs) ( 11–15 ) are promising as effectively catalyst in working device design, particularly taking into account the eco‐friendly approach of the hybrids. 相似文献
82.
Ghommem Mehdi Najar Fehmi Arabi Mohamed Abdel-Rahman Eihab Yavuz Mustafa 《Nonlinear dynamics》2020,101(1):271-291
Nonlinear Dynamics - We present a unified model of electrostatic sensors comprising cantilever microbeam resonators in fluid media. The model couples Euler–Bernoulli beam equation to the... 相似文献
83.
The decolorisation process of a synthetic textile dye, direct violet 51, was investigated in an aqueous solution using an electrochemical method in a batch electrochemical cell. Graphite electrodes were used as the anode and cathode for the decolorisation process. The parameters such as applied current, initial pH, solution conductivity, interfering ions, and effect of electrodes were optimised. It was found that the dye with an initial concentration of 20 mg L?1 could be removed after 50 min using a current of 100 mA with colour removal of up to 94 %. The UV-VIS spectra of the dye were analysed prior to and after treatment and these confirmed that the conjugated systems were decomposed at a current of 100 mA. The optimised method was successfully applied to real wastewater samples. 相似文献
84.
Cevher Gündoğdu Hızlıateş Sibel Gülle Yavuz Ergün 《Journal of heterocyclic chemistry》2016,53(1):249-254
The novel heterocyclic compounds that have cycloalk[b]indole moiety bearing spiropiperidinone and spiropiperidinedione ( 3a , 3b , 3c , 5a , 5b , 8a , 8b , and 10a ) were synthesized for the first time. The synthesis of spiropiperidinone and spiropiperidinedione structures was performed by a new method. These compounds are similar to sedative and hypnotic drugs such as methyprylon, glutethimide, and thalidomide. 相似文献
85.
Bahittin Kahveci Musa Özil Selami ?a?maz Yavuz Köysal 《Journal of organometallic chemistry》2007,692(22):4835-4842
New metal-free and metal (Zn, Ni, Cu and Co) phthalocyanines containing 4-(p-fluorophenyl)-3-methyl-4,5-dihydro-1H-1,2,4-triazol-5-one moiety have been prepared from 1-(3,4-dicyanophenyl)-4-(p-fluorophenyl)-3-methyl-4,5-dihydro-1H-1,2,4-triazol-5-one by both conventional and microwave-assisted methods. All of these compounds are soluble in CHCl3, DMF and DMSO. The new compounds have been characterized by elemental analysis, IR, NMR, UV-Vis spectroscopies. The crystal structures of compounds I and II were also determined by the single crystal diffraction technique. 相似文献
86.
Addition reactions of nucleophilic CF3TMS to acyl phosphonates were investigated. Various acyl phosphonates reacted readily with CF3TMS in the presence of K2CO3 in DMF at rt to give 1-alkyl-2,2,2-trifluoro-1-trimethylsilyloxyethylphosphonate in 70-90% yields. When benzoyl phosphonates were used as starting material, after addition of CF3, the formed alcoholate undergoes phosphonate-phosphate rearrangement to form the acyl anion, followed by elimination of F- to give 1-aryldifluoroethenyl phosphates in 87-97% yields. As a representative example, vinylphosphate 6a was converted into 2,2-difluoro-1-phenylethanone 7 with 6 N HCl/EtOH/reflux or CAN/NaOH/MeOH/0 degrees C in 82-90% yields. 相似文献
87.
In this paper, derivation of analytical expressions
for overlap integrals with the same and different screening parameters
of Slater type orbitals (STOs) via the Fourier-transform method
is presented. Consequently, it is relatively easy to express
the Fourier integral representations of the overlap integrals
with same and different screening parameters mentioned as finite
sums of Gegenbauer, Gaunt, binomial coefficients, and STOs. 相似文献
88.
Leyla Gündoğdu Nihan Şen Cevher Gündoğdu Hızlıateş Mustafa Yavuz Ergün 《Journal of fluorescence》2017,27(6):2095-2100
Four new carbazole-oxadiazole derivatives (3a-b, 6a-b) were prepared from the reaction of aromatic aldehydes and carbohydrazides which were synthesized from carbazole aldehydes namely 9-hexyl-9H-carbazole-3-carbaldehyde 1 and 4-(9H-carbazole-9-yl)benzaldehyde 4 and acid hydrazides. The structures of the new derivatives were confirmed by 1H-NMR and FT-IR. The optical properties such as maximum absorption and emission wavelengths (λ; nm), molar extinction coefficients (ε; cm?1 M?1), Stoke’s shifts (ΔλST; nm) and quantum yields (?F), of the carbazole-oxadiazole derivatives were declared in dichloromethane, toluene and tetrahydrofuran solutions. 相似文献
89.
Yavuz Kysal amil Ik Gülay ahin Erhan Palaska 《Acta Crystallographica. Section C, Structural Chemistry》2005,61(9):o542-o544
The structures of N‐ethyl‐3‐(4‐fluorophenyl)‐5‐(4‐methoxyphenyl)‐2‐pyrazoline‐1‐thiocarboxamide, C19H20FN3OS, (I), and 3‐(4‐fluorophenyl)‐N‐methyl‐5‐(4‐methylphenyl)‐2‐pyrazoline‐1‐thiocarboxamide, C18H18FN3S, (II), have similar geometric parameters. The methoxy/methyl‐substituted phenyl groups are almost perpendicular to the pyrazoline (pyraz) ring [interplanar angles of 89.29 (8) and 80.39 (10)° for (I) and (II), respectively], which is coplanar with the fluorophenyl ring [interplanar angles of 5.72 (9) and 10.48 (10)°]. The pyrazoline ring approximates an envelope conformation in both structures, with the two‐coordinate N atom involved in an intramolecular N—H⋯Npyraz interaction. In (I), N—H⋯O and C—H⋯S intermolecular hydrogen bonds are the primary interactions, whereas in (II), there are no intermolecular hydrogen bonds. 相似文献
90.