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91.
Cemil İbiş Nihal Yilmaz Bozkurt 《Phosphorus, sulfur, and silicon and the related elements》2013,188(3):695-701
Nitrodiene compound 1 was stirred with allylthiol for a long time and compound 3 was obtained. Compound 1 gave bis(thio)substituted 2-nitrodiene compound 4 and tris(thio)substituted 2-nitrodiene compound 5 with 2 moles allylthiol in the presence of NaOH in ethanol. Mono(allylthio)substituted diene compound 3 gave dibutadienyl substituted piperazine compounds with piperazine 6 in CH 2 Cl 2 (or diethylether). Compound 3 gave compound 9 with compound 8 . Compounds 11a-e have been obtained from the reaction of compound 3 with compounds 10a-e . Nach langem Rühren von der Verbindung 1 mit Allylthiol entsteht die Verbindung 3 . Die Verbindung 1 liefert mit zwei Mol von Allylthiol in ethanolischer Natronlunge die bis(thio)substituierte 2-Nitrodienverbindung 4 und tris(thio)substituierte Dienverbindung 5 . Mono(allylthio)substituierte Dienverbindung 3 ergibt mit Piperazine in CH 2 Cl 2 (oder in Ether) die dibutadienylsubstituierte Piperazinverbindung 7 . Die Verbindung 3 liefert mit der Verbindung 8 die Verbindung 9 . Durch die Reaktion von der Verbindungen 10a-c wurden die Verbindungen 11a-e erhalten. 相似文献
92.
Yasemin Soydas Bozkurt Halil Kutuk 《Phosphorus, sulfur, and silicon and the related elements》2013,188(11):2250-2257
Abstract In this study, some N-(p-substituted-arylsulfinyl)phthalimides (1a–1e) were synthesized. The synthesized compounds were examined with respect to their substitution reactions with sodium ethoxide, sodium methoxide, methylamine, and t-butylamine in dioxane. The substituent effect was investigated at 30.0 ± 0.1 °C. The activation entropy was also studied, and negative ΔS≠ values were obtained. Configuration inversions were observed in the substitution reactions. This result is in conformity with the SN2 mechanism. [Supplemental materials are available for this article. Go to the publisher's online edition of Phosphorus, Sulfur, and Silicon and the Related Elements for the following free supplemental resource: Characterization of -(p-Substituted-arylsulfinyl)phthalimides 1a–b.] 相似文献
93.
In this article, we investigated the sequence specific interaction of single (ssDNA) and double stranded (dsDNA) with silver ions (Ag+) with electrochemical methods. We, for the first time, examined the effect of base sequences, base content and physiochemical properties of different DNA sequences on interaction with Ag+ in detail. We used different base contents to show how the composition of nucleic acid influences the electrochemical signals. We first immobilized ssDNA probes on bare graphite electrodes. Then, we showed the sequence effect on oxidation signals of AgDNA complex by sensing Ag+ to the probe coated surfaces to interact with different ssDNA sequences. Furthermore, we investigated the effect of Ag+ on dsDNA. We measured the oxidation signals obtained from Ag+‐ssDNA and Ag+‐dsDNA complex at approximately 0.2 V and 1.0 V (vs Ag/AgCl), respectively with Differential Pulse Voltammetry (DPV). We showed that the oxidation signals of the AgDNA complex obtained from dsDNA‐modified electrodes is higher than the electrodes modified with ssDNA. More importantly, we showed that Ag+‐ssDNA and Ag+ ion‐dsDNA exhibit different electrochemical behaviors. 相似文献
94.
We demonstrated the application of a simple electrode geometry for dielectrophoresis (DEP) on colloidal probes as a form of molecular force spectroscopy in a highly parallel format. The electric field between parallel plates is perturbed with dielectric microstructures, generating uniform DEP forces on colloidal probes in the range of several hundred piconewtons across a macroscopic sample area. We determined the approximate crossover frequency between negative and positive DEP using electrodes without dielectric microstructures-a simplification over standard experimental methods involving quadrupoles or optical trapping. 2D and 3D simulations of the electric field distributions validated the experimental behavior of several of our DEP tweezers geometries and provided insight into potential improvements. We applied the DEP tweezers to the stretching of a short DNA oligomer and detected its extension using total-internal reflection fluorescence microscopy. The combination of a simple cell fabrication, a uniform distribution of high axial forces, and a facile optical detection of our DEP tweezers makes this form of molecular force spectroscopy ideal for highly parallel detection of stretching or unbinding kinetics of biomolecules. 相似文献
95.
K. Baker G. Cantatore S. A. Cetin M. Davenport K. Desch B. Döbrich H. Gies I. G. Irastorza J. Jaeckel A. Lindner T. Papaevangelou M. Pivovaroff G. Raffelt J. Redondo A. Ringwald Y. Semertzidis A. Siemko M. Sulc A. Upadhye K. Zioutas 《Annalen der Physik》2013,525(6):A93-A99
Standard Model extensions often predict low‐mass and very weakly interacting particles, such as the axion. A number of small‐scale experiments at the intensity/precision frontier are actively searching for these elusive particles, complementing searches for physics beyond the Standard Model at colliders. Whilst a next generation of experiments will give access to a huge unexplored parameter space, a discovery would have a tremendous impact on our understanding of fundamental physics. 相似文献
96.
Halay Erkan Bozkurt Selahattin Capan Rifat Erdogan Matem Unal Ridvan Acikbas Yaser 《Research on Chemical Intermediates》2020,46(10):4433-4445
Research on Chemical Intermediates - The detection of organic vapors by chemically based sensors was achieved with macromolecules having convenient molecular cavities. Addressed herein, a... 相似文献
97.
The isoscalar monopole response is studied in doubly magic 208Pb , 100, 132Sn nuclei using the Skyrme HF+RPA model. A low-energy strength is predicted and corresponds to almost pure single-particle excitations. These pure single-particle excitations allow to analyse the splitting of the corresponding spin-orbit partners. A good agreement with the spin-orbit splitting data is found in the case of 208Pb . The experimental width of the giant monopole resonance may hinder the measurement of the soft monopole mode. 相似文献
98.
Synthesis of bistriphenylamine‐ and benzodithiophene‐based random conjugated polymers for organic photovoltaic applications 下载免费PDF全文
Asli Cetin Cagla Istanbulluoglu Serife Ozdemir Hacioglu Sevki Can Cevher Levent Toppare Ali Cirpan 《Journal of polymer science. Part A, Polymer chemistry》2017,55(22):3705-3715
In this study, donor–acceptor random polymers containing benzotriazole acceptor and bistriphenylamine and benzodithiophene donors, P1 and P2 , were successfully synthesized by Stille coupling polymerization. The effect of bistriphenylamine moiety and thiophene π‐conjugated linker on electrochemical, spectroelectrochemical, and optical behaviors of the polymers were investigated. Optoelectronic properties and photovoltaic performance of the polymers were examined under the illumination of AM 1.5G, 100 mW cm?2. The polymers were characterized by cyclic voltammetry, UV‐Vis‐NIR absorption spectroscopy, gel permeation chromatography. HOMO/LUMO energy levels of P1 and P2 were calculated as ?5.47 eV/–3.41 eV and ?5.43 eV/–3.27 eV, respectively. Bulk heterojunction type solar cells were constructed using blends of the polymers (donor) and [6,6]‐phenyl C71 butyric acid methyl ester (PC71BM) (acceptor). Photovoltaic studies showed that the highest power conversion efficiency of these photovoltaic devices were recorded as 3.50% with open circuit voltage; 0.79 V, short circuit current; 9.45 mA cm?2, fill factor; 0.53 for P1 :PC71BM (1:2, w/w) in 3% o‐dichlorobenzene (o‐DCB) solution and 3.15% with open circuit voltage; 0.75 V, short circuit current; 8.59 mA cm?2, fill factor; 0.49 for P2 :PC71BM (1:2, w/w) in 2% chlorobenzene (CB) solution. © 2017 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2017 , 55 , 3705–3715 相似文献
99.
Ali Deliceoğlu Deniz Bozkurt Ebutalib Çelik 《Mathematical Methods in the Applied Sciences》2020,43(15):8317-8326
Flow development and eddy structure in an L-shaped cavity with lids moving in the same directions have been investigated using both tools from topological and numerical methods. In particular, structural bifurcation near a nonsimple degenerate point is investigated by making a local analysis of the velocity field based on a Taylor series expansion. The streamlines of a Hamiltonian vector field system are simplified by using the homotopy invariance of the index theory. A series of bifurcation curves are constructed to determine the sequence of flow structures by which eddies are generated in the L-shaped cavity. 相似文献
100.
Modeling and control of vehicle suspension system are high noteworthy from safety to comfort. In this paper, an analytical
nonlinear half-vehicle model which is included quadratic tire stiffness, cubic suspension stiffness, and coulomb friction
is derived based on fundamental physics. A hybrid fuzzy logic approach which combines fuzzy logic and PID controllers is designed
for reducing the vibration levels of passenger seat and vehicle body. Performances of designed controllers have been evaluated
by numerical simulations. Comparisons with classical PID control, Fuzzy Logic Control (FLC) and Hybrid Fuzzy-PID control (HFPID)
have also been provided. Results of numerical simulations are evaluated in terms of time histories of displacement and acceleration
responses and ride index comparison. A good performance for the Hybrid Fuzzy-PID controller with coupled rules (HFPIDCR) is
achieved in simulation studies despite the nonlinearities. 相似文献