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21.
In this article, we find elements of the Lucas polynomials by using two matrices. We extend the study to the n-step Lucas polynomials. Then the Lucas polynomials and their relationship are generalized in the paper. Furthermore, we give relationships between the Fibonacci polynomials and the Lucas polynomials. 相似文献
22.
İzzet Amour Morkan Ayşe Uztetik Morkan Çiğdem Tuç Engin Kendi 《Journal of chemical crystallography》2008,38(7):541-545
Abstract Pentacarbonyl(4-methylpyridine)chromium(0) complex was isolated from n-hexane solution as yellow plate-like crystals and characterized by using X-ray crystallography. It crystallizes in the orthorhombic
system with the space group Cmcm and Z = 4. The unit cell parameters are a = 11.737(1) ?, b = 12.857(2) ?, c = 8.465(1) ?. The single crystal X-ray structure of the complex shows that the coordination sphere around the chromium central
atom is slightly distorted octahedron, involving the 4-methylpyridine (4-mp), ligand as a monodentate N-donor ligand and five
carbonyl groups. The four equatorial CO groups in the complex, with the Cr–C2 distance of 1.886 Ǻ, are slightly bent away
from the 4-methylpyridine ligand with the N–Cr–C2 angle of 91.69°. The pyridine ring plane makes an angle of 135.17° with
the Cr–N–CO bond axis. The thermal analysis (differential thermal analysis and thermal gravimetry) and IR spectra of the complex
indicated that the compound undergoes complete decomposition to form the Cr2O3 as the final decomposition product.
Index Abstract The crystal structure of pentacarbonyl(4-methylpyridine)chromium(0) complex has been determined and its thermal behavior has
also been studied.
相似文献
23.
Ionics - This study is related to the development of a highly sensitive and selective electrode for the electroanalysis of dicofol (DCF) by the modification of a glassy carbon electrode (GCE) with... 相似文献
24.
Jin Li Dr. Lei Wang Jinrong Li Yujie Shao Ziang Liu Dr. Guangzhe Li Prof. Dr. Engin U. Akkaya 《Chemistry (Weinheim an der Bergstrasse, Germany)》2022,28(34):e202200506
Naphthalene endoperoxides are known as convenient sources of singlet oxygen (O2, 1Δg), which is the major product of endoperoxide cycloreversion reaction. However, their potential as carriers of ground-state molecular oxygen (O2, 3Σg) similar to artificial oxygen carriers remains largely unexplored. This is due to the extreme reactivity and cytotoxic effects of the released singlet oxygen. We now report that a compound with a bimodular design, which incorporates an endoperoxide and an efficient physical quencher of singlet oxygen, 1,4-diazabicyclo[2.2.2]octane (DABCO), produces exclusively ground-state molecular oxygen. This result, coupled with the fact that oxygen release rates from endoperoxides are highly amenable to fine-tuning in a very broad range, and open to targeting by ligand attachment, raises the potential of these compounds far above any comparable chemical, or even biochemical sources. In cell culture experiments, we showed that the addition of the endoperoxide-quencher conjugate can enhance and sustain cell proliferation. 相似文献
25.
Paul T. Beurskens M. Kolenbrander J. H. Noordik V. Parthasarathi Engin Kendi 《Journal of chemical crystallography》1986,16(4):459-465
The structure of the title compound C21H22O3, was determined by X-rays.Minr=322.4, monoclinic, space groupP21/a,a=11.960(2),b=14.275(3),c=10.858(2) Å,=103.20(2)°,V
c
=1804.8 Å3,Z=4,D
x
=1.223 Mg m–3. CuK radiation (graphite crystal monochromator,=1.54184 Å),(CuK)=6.53 cm–1,F(000)=688, T=290 K. Final conventionalR factor=0.050,R
w
=0.069 for 1679 unique reflections and 284 variables. The structure was solved usingMultan. 相似文献
26.
Detection of Variation in Long-Term Micropropagated Mature Pistachio via DNA-Based Molecular Markers
Hülya Akdemir Veysel Suzerer Engin Tilkat Ahmet Onay Yelda Ozden Çiftçi 《Applied biochemistry and biotechnology》2016,180(7):1301-1312
Determination of genetic stability of in vitro-grown plantlets is needed for safe and large-scale production of mature trees. In this study, genetic variation of long-term micropropagated mature pistachio developed through direct shoot bud regeneration using apical buds (protocol A) and in vitro-derived leaves (protocol B) was assessed via DNA-based molecular markers. Randomly amplified polymorphic DNA (RAPD), inter-simple sequence repeat (ISSR), and amplified fragment length polymorphism (AFLP) were employed, and the obtained PIC values from RAPD (0.226), ISSR (0.220), and AFLP (0.241) showed that micropropagation of pistachio for different periods of time resulted in “reasonable polymorphism” among donor plant and its 18 clones. Mantel’s test showed a consistence polymorphism level between marker systems based on similarity matrices. In conclusion, this is the first study on occurrence of genetic variability in long-term micropropagated mature pistachio plantlets. The obtained results clearly indicated that different marker approaches used in this study are reliable for assessing tissue culture-induced variations in long-term cultured pistachio plantlets. 相似文献
27.
Remote‐Controlled Release of Singlet Oxygen by the Plasmonic Heating of Endoperoxide‐Modified Gold Nanorods: Towards a Paradigm Change in Photodynamic Therapy 下载免费PDF全文
Dr. Safacan Kolemen Dr. Tugba Ozdemir Dayoung Lee Gyoung Mi Kim Tugce Karatas Prof. Juyoung Yoon Prof. Engin U. Akkaya 《Angewandte Chemie (International ed. in English)》2016,55(11):3606-3610
The photodynamic therapy of cancer is contingent upon the sustained generation of singlet oxygen in the tumor region. However, tumors of the most metastatic cancer types develop a region of severe hypoxia, which puts them beyond the reach of most therapeutic protocols. More troublesome, photodynamic action generates acute hypoxia as the process itself diminishes cellular oxygen reserves, which makes it a self‐limiting method. Herein, we describe a new concept that could eventually lead to a change in the 100 year old paradigm of photodynamic therapy and potentially offer solutions to some of the lingering problems. When gold nanorods with tethered endoperoxides are irradiated at 808 nm, the endoperoxides undergo thermal cycloreversion, resulting in the generation of singlet oxygen. We demonstrate that the amount of singlet oxygen produced in this way is sufficient for triggering apoptosis in cell cultures. 相似文献
28.
Simultaneous Identification of Spectral Properties and Sizes of Multiple Particles in Solution with Subnanometer Resolution 下载免费PDF全文
Assist. Prof. Engin Karabudak Dr. Emre Brookes Dr. Vladimir Lesnyak Prof. Dr. Nikolai Gaponik Prof. Dr. Alexander Eychmüller Johannes Walter Dr. Doris Segets Prof. Wolfgang Peukert Dr. Wendel Wohlleben Assoc. Prof. Borries Demeler Prof. Dr. Helmut Cölfen 《Angewandte Chemie (International ed. in English)》2016,55(39):11770-11774
We report an unsurpassed solution characterization technique based on analytical ultracentrifugation, which demonstrates exceptional potential for resolving particle sizes in solution with sub‐nm resolution. We achieve this improvement in resolution by simultaneously measuring UV/Vis spectra while hydrodynamically separating individual components in the mixture. By equipping an analytical ultracentrifuge with a novel multi‐wavelength detector, we are adding a new spectral discovery dimension to traditional hydrodynamic characterization, and amplify the information obtained by orders of magnitude. We demonstrate the power of this technique by characterizing unpurified CdTe nanoparticle samples, avoiding tedious and often impossible purification and fractionation of nanoparticles into apparently monodisperse fractions. With this approach, we have for the first time identified the pure spectral properties and band‐gap positions of discrete species present in the CdTe mixture. 相似文献
29.
Palladium‐catalyzed Suzuki reaction using 1,3‐dialkylbenzimidazol‐2‐ylidene ligands in aqueous media
smail
zdemir Yetkin Gk Nevin Gürbüz Engin etinkaya Bekir etinkaya 《Heteroatom Chemistry》2004,15(6):419-423
From readily available starting compounds, six functionalized 1,3‐dialkylbenzimidazolium salts ( 2a–c and 4a–c ) have been prepared and characterized by conventional spectroscopic methods and elemental analyses. A highly effective, easy to handle, and environmentally benign process for palladium‐mediated Suzuki cross‐coupling was developed. The in situ prepared three‐component systems Pd(OAc)2/1,3‐dialkylbenzimidazolium chlorides and Cs2CO3 catalyze quantitatively the Suzuki cross‐coupling of deactivated aryl chlorides. © 2004 Wiley Periodicals, Inc. Heteroatom Chem 15:419–423, 2004; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/hc.20034 相似文献
30.
Engin Asav 《Talanta》2009,78(2):553-987
In this study, a new biosensor based on the inhibition of tyrosinase for the determination of fluoride is described. To construct the biosensor tyrosinase was immobilized by using gelatine and cross-linking agent glutaraldehyde on a Clark type dissolved oxygen (DO) probe covered with a teflon membrane which is sensitive for oxygen. The phosphate buffer (50 mM, pH 7.0) at 30 °C were established as providing the optimum working conditions. The method is based on the measurement of the decreasing of dissolved oxygen level of the interval surface that related to fluoride concentration added into reaction medium in the presence of catechol. Inhibitor effect of fluoride results in decrease in dissolved oxygen concentration. The biosensor response depends linearly on fluoride concentration between 1.0 and 20 μM with a response time of 3 min.In the characterization studies of the biosensor some parameters such as reproducibility, substrate specificity and storage stability were carried out. From the experiments, the average value (x), Standard deviation (S.D) and coefficient of variation (C.V %) were found as 10.5 μM, ± 0.57 μM, 5.43%, respectively for 10 μM fluoride standard. 相似文献