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111.
Electrical and photoelectrical behaviour of heterojunctions based on novel oligomeric metal complexes 下载免费PDF全文
Metin Atlan Yusuf Selim Ocak Salih Pasa Hamdi Temel Ahmet Tombak Tahsin Kilicoğlu Kemal Akkilic Murat Aydemir 《应用有机金属化学》2015,29(12):798-804
Naringenin‐based Schiff base ligands with 4‐aminobenzoic hydrazide were obtained as a unilateral form ( L1 ). The ligand was oligomerized by oxidative polycondensation reaction with NaOCl as an oxidant in an aqueous alkaline medium at 90 °C to form a functional oligomer ( L2 ), and its transition metal complexes such as those with Cu(II), Ni(II) and Zn(II) were prepared. The monomer and the oligomeric compounds were characterized using various techniques. Optical and electrical properties of the complexes were also investigated. All compounds showed indirect band gaps and they can be accepted as being in the semiconductor class. Organic–inorganic hybrid devices were obtained using n‐Si inorganic semiconductor and the complexes. The characteristic parameters of the devices were determined using current–voltage (I–V) and capacitance–voltage measurements in the dark. Photoelectrical properties of the devices were investigated using I–V measurements under a solar simulator with an AM1.5 global filter. Copyright © 2015 John Wiley & Sons, Ltd. 相似文献
112.
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114.
In this work, a new polymer resin with a functional groups capable of holding trace metals has been synthesized. The structure of polymer resin has been examined by BET-N2 method analyzer, IR spectrometer, scanning electron microscope (SEM) and elemental microanalyser. The synthesized polymer resin was used for the simultaneous separation and preconcentration of the trace metals from various tea and herbal plants samples. After extraction process, flame atomic absorption spectrometry (FAAS) was used to determine the trace metals. The analytical parameters and solid phase extraction (SPE) performance such as pH, sample volume, flow rates of sample, flow rates of eluent, concentration, volume and type of eluent and effect of interference ions, were investigated. The limits of detection (DL) of the SPE procedure for trace metals, were calculated to be (3s) in the range of 0.9?4.0 μg L?1 (n = 21) and the factors of preconcentration (PF) were obtained at 200 for Cd, Co, Cu, Fe, Ni and Zn, and at 50 for Cr, Mn and Pb ions and the relative standard deviation (RSD) at ≤ 2% (n = 11). 相似文献
115.
116.
The protein environments surrounding the retinal tune electronic absorption maximum from 350 to 630 nm. Hybrid quantum mechanical/molecular mechanical (QM/MM) methods can be used in calculating excitation energies of retinal in its native protein environments and in studying the molecular basis of spectral tuning. We hereby review recent QM/MM results on the phototransduction of bovine rhodopsin, bacteriorhodopsin, sensory rhodopsin II, nonretinal photoactive yellow protein and their mutants. 相似文献
117.
Five new metal complexes [Pd(LH)2] (1), [Pd(L)2Ru2(bpy)4](ClO4)2 (2), [Pd(L)2Ru2(phen)4](ClO4)2 (3), [Pd(L)2Ru2(dafo)4](ClO4)2 (4) and [Pd(L)2Ru2(dcbpy)4](ClO4)2 (5), (where, L = ligand, bpy = 2,2′-bipyridine, phen = 1,10-phenantroline, dafo = 4,5-diazafluoren-9-one and dcbpy = 3,3′-dicarboxy-2,2′-bipyridine) have been isolated and characterized by UV-VIS, FT-IR, 1H NMR, magnetic susceptibility measurements, elemental analysis, molar conductivity, X-ray powder techniques, thermal analyses and their morphology studied by SEM measurements. IR spectra show that the ligand acts in a tetradentate manner and coordinates N4 donor groups of LH2 to PdII ion. The disappereance of H-bonding (O−H···O) in the trinuclear RuII-PdII-RuII metal complexes, the RuII ion centered into the main oxime core by the coordination of the imino groups while the two RuII ions coordinate dianionic oxygen donors of the oxime groups and linked to the ligands of bpy, phen, dafo and dbpy. The X-powder results show that 1 metal complex is indicating crystalline nature, not amorphous nature. Whereas, the X-ray powder pattern of the ligand (LH2) with 2, 3,4 and 5 exhibited only broad humps, indicating its amorphous nature. The catalytic activity of three different complexes were tested in the Suzuki coupling reaction. The 1, 4 and 5 metal complexes catalyse Suzuki coupling reaction between phenylboronic acid and arylbromides affording biphenyls. Also, the thermal results shown that the most stable complex is 1 compound while the less stable is 4 compound. 相似文献
118.
Three novel vic-dioxime ligands containing the 1,8-diamino-3,6-dioxaoctane group, N,N′-(1,8-diamino-3,6-dioxaoctane)-p-tolylglyoxime (L1SL1H4), N,N′-(1,8-diamino-3,6-dioxaoctane)-phenylglyoxime (L2SL2H4), and N,N′-(1,8-diamino-3,6-dioxaoctane)-glyoxime (L3SL3H4) have been prepared from 1,8-diamino-3,6-dioxaoctane with anti-p-tolylchloroglyoxime, anti-phenylchloroglyoxime or anti-monochloroglyoxime. Polynuclear complexes [M(L
x
SL
x
)]
n
or [M(L
x
SL
x
)(H2O)]
n
(x = 1, 2 and 3), where M = CuII, CoII, and NiII, have been obtained with 1:1 metal/ligand ratio. The CuII and NiII poly-metal complexes of these ligands are proposed to be square planar, while also the prepared CoII complexes are proposed to be octahedral with two water molecules as axial ligands. The detection of H-bonding in the [Ni(L1SL1)]
n
, [Ni(L2SL2)]
n
and [M(L3SL3)(H2O)]
n
metal complexes by FT i.r. spectra revealed the square planar or octahedral [MN4·H2O)]
n
coordination of poly-nuclear metal complexes. [MN4]
n
coordination of the [Ni(L1SL1)]
n
and [Ni(L2SL2)]
n
complexes were also determined by 1H-n.m.r. spectroscopy. The ligands and poly-metal complexes were characterized by elemental analyses, FT-i.r., u.v.-vis.,
1H and 13C-n.m.r. spectra, magnetic susceptibility measurements, molar conductivity, cyclic voltammetry, and differential pulse voltammetric
(DPV) techniques. 相似文献
119.
Magnesium porphyrazinate substituted with eight 4-tert-butylphenylthio-groups on the peripheral positions has been synthesized by cyclotetramerization of 1,2-bis(4-tert-butylphenylthio)maleonitrile in the presence of magnesium butanolate. The metal-free derivative was obtained by its treatment with trifluoroacetic acid and further reaction of this product with copper(II) acetate, zinc(II) acetate and cobalt(II) acetate led to the metal porphyrazinates (M = Cu, Zn, Co). These new compounds have been characterized by elemental analysis, together with FT-IR, 1H NMR, UV–Vis spectral data. By using EPR technique, room temperature paramagnetic properties of Cu(II) doped porphyrazine sample as powder and solution forms were measured. The first-derivative EPR signals taken from as powder and solution forms shows that the sample is axially symmetric. The trend g∥ > g⊥ > 2 indicates that the unpaired electron is located mainly in the dx2-y2 orbital (2B1 as ground state). 相似文献
120.
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