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1.
Sevim Akyuz Meric Bakiler Liljana Andreeva Biljana Minceva-Sukarova 《Journal of inclusion phenomena and macrocyclic chemistry》2004,48(1-2):25-29
Hofmann-type modified clathrate hosts containing 2- or 3-chloropyridine molecules attached to metal (II) tetracyanocadmate frame, with a given formula: M(Clpy)2Cd(CN)4 where M = Mn, Ni or Cd; Clpy = 2- or 3-chloropyridine, have been synthesised for the first time. Their FT-IR spectra are reported in the 400–4000 cm-1 region. All the vibrational modes of coordinated Clpy are characterised. The spectral features of the compounds studied are found to be similar to each other indicating that they have analogous structures. The coordination effect on the Clpy modes is analyzed. 相似文献
2.
The molecular structures and vibrational spectra of the three isomers of pyridinecarboxamide (picolinamide, nicotinamide, isonicotinamide) were calculated with the Density Functional Theory (DFT) method using the B3LYP function and the 6-31++G(d,p), Z2PolX, Z3PolX basis sets. The calculations were performed by using the Gaussian98W packet program set. The total energy distributions (TED) of the vibrational modes of these molecules were calculated by using the Scale 2.0 program and the vibrational modes of the molecules were determined. The Scaled Quantum Mechanical (SQM) method was used in the scaling procedure. In the experimental part of the study, the solid phase FT-IR and Micro Raman spectra of the three isomers of pyridinecarboxamide have been recorded in the range of 4000-650 and 1200-100 cm−1, respectively. The calculated wavenumbers were compared to the corresponding experimental values. As a result, the observed bands of the three isomers of pyridinecarboxamide were assigned with good accuracy. 相似文献
3.
Sibel Topuz Buket Alpertunga 《International journal of environmental analytical chemistry》2013,93(9):787-795
A rapid and selective method for the simultaneous determination of triazine herbicides (atrazine, its degradation product desethylatrazine, simazine, prometryn, terbutryn) and N-methylcarbamate insecticides (propoxur, carbaryl and methiocarb) in surface water has been developed. A 0.5 L of the water sample was preconcentrated by passage through a 1 g C18 solid-phase extraction cartridge. The retained compounds were eluted with 5 mL of methanol from the cartridge. The pesticides were separated and quantified by reversed-phase high-performance liquid chromatography with UV diode-array detection. Analytical separation was performed using a concave gradient elution with acetonitrile and water on a C18 column. Prometryn and terbutryn were determined at 240 nm; propoxur, methiocarb at 204 nm and the others at 220 nm. Recoveries varied from 85 to 102% over concentrations at 0.025 and 0.2 µg L?1. The limits of detection for the compounds investigated are in the range of 0.005-0.012 µg L?1. 相似文献
4.
Yasin Ugur Kayran Dilsat Ozkan‐Ariksoysal Burcin Tezcanli Buket Kosova Mehmet Ozsoz 《Electroanalysis》2013,25(12):2668-2676
In this study, for the first time a model electrochemical kit was constructed for the detection of a functional polymorphism in catechol‐O‐methyl transferase (COMT) gene which is important for diagnosis of neuropsychiatric disorders as Alzheimer disease. The disposable pencil graphite electrode (PGE) is designed as a “kit” and the probe DNA covered PGE can detect single nucleotide polymorphisms (SNPs) from real samples based on the guanine oxidation signal even after 5 months of kit preparation (150 days durability).The detection limit (S/N=3) of the biosensor was calculated as 1.18 pmol of synthetic target sequence and 6.09×105 molecules of real samples in 30 min detection time. 相似文献
5.
Avcıbaşı Uğur Türkyarar Taner Karadağ Ayşegül Bakan Buket Yavaşoğlu Nefise Ülkü Karabay Kuşat Kevser Akgöl Sinan Gülcemal Derya Tekin Volkan Müftüler Fazilet Zümrüt Biber Topal Gökcen Parlak Yasemin Gümüşer Fikriye Gül 《Journal of Radioanalytical and Nuclear Chemistry》2021,329(2):511-525
Journal of Radioanalytical and Nuclear Chemistry - The aim of this study is the synthesis of a novel 99mTc-labeld graft polymer and the biological evaluation of its in vitro and in vivo properties.... 相似文献
6.
A modified electrode was fabricated by electrochemically deposition of Pt nanoparticles on the multiwall carbon nanotube covered glassy carbon electrode (Pt nanoparticles decorated MWCNT/GCE). A higher catalytic activity was obtained to electrocatalytic oxidation of ascorbic acid, dopamine, and uric acid due to the enhanced peak current and well‐defined peak separations compared with both, bare and MWCNT/GCE. The electrode surfaces were characterized by scanning electron microscopy (SEM), X‐ray diffraction (XRD) and electrochemical impedance spectroscopy (EIS). Individual and simultaneous determination of AA, DA, and UA were studied by differential pulse voltammetry. The detection limits were individually calculated for ascorbic acid, dopamine, and uric acid as being 1.9×10?5 M, 2.78×10?8 M, and 3.2×10?8 M, respectively. In simultaneous determination, LODs were calculated for AA, DA, and UA, as of 2×10?5 M, 4.83×10?8 M, and 3.5×10?7 M, respectively. 相似文献
7.
Murat Aydemir Nermin Meric Akın Baysal Bahattin Gümgüm Mahmut Toğrul Yılmaz Turgut 《Tetrahedron: Asymmetry》2010,21(6):703-710
Hydrogen-transfer reduction processes are attracting increasing interest from synthetic chemists in view of their operational simplicity. The new chiral C2-symmetric ligands N,N′-bis-[(1S)-1-sec-butyl-2-O-(diphenylphosphinite)ethyl]ethanediamide, 1 and N,N′-bis-[(1S)-1-phenyl-2-O-(diphenylphosphinite)ethyl]ethanediamide, 2 and the corresponding ruthenium complexes 3 and 4 have been prepared and their structures have been elucidated by a combination of multi-nuclear NMR spectroscopy, IR spectroscopy, and elemental analysis. 1H–31P NMR, DEPT, 1H–13C HETCOR, or 1H–1H COSY correlation experiments were used to confirm the spectral assignments. The catalytic activity of complexes 3 and 4 in transfer hydrogenation of acetophenone derivatives by iso-PrOH has also been studied. Under optimized conditions, these chiral ruthenium complexes serve as catalyst precursors for the asymmetric transfer hydrogenation of acetophenone derivatives in iso-PrOH and act as excellent catalysts, giving the corresponding chiral alcohols in 99% yield and up to 75% ee. This transfer hydrogenation is characterized by low reversibility under these conditions. 相似文献
8.
Pharmaceutical residues in environmental waters and wastewater: current state of knowledge and future research 总被引:4,自引:0,他引:4
Pollution from pharmaceuticals in the aquatic environment is now recognized as an environmental concern in many countries.
This has led to the creation of an extensive area of research, including among others: their chemical identification and quantification;
elucidation of transformation pathways when present in wastewater-treatment plants or in environmental matrices; assessment
of their potential biological effects; and development and application of advanced treatment processes for their removal and/or
mineralization. Pharmaceuticals are a unique category of pollutants, because of their special characteristics, and their behavior
and fate cannot be simulated with other chemical organic contaminants. Over the last decade the scientific community has embraced
research in this specific field and the outcome has been immense. This was facilitated by advances in chromatographic techniques
and relevant biological assays. Despite this, a number of unanswered questions exist and still there is much room for development
and work towards a more solid understanding of the actual consequences of the release of pharmaceuticals in the environment.
This review tries to present part of the knowledge that is currently available with regard to the occurrence of pharmaceutical
residues in aquatic matrices, the progress made during the last several years on identification of such compounds down to
trace levels, and of new, previously unidentified, pharmaceuticals such as illicit drugs, metabolites, and photo-products.
It also tries to discuss the main recent findings in respect of the capacity of various treatment technologies to remove these
contaminants and to highlight some of the adverse effects that may be related to their ubiquitous existence. Finally, socioeconomic
measures that may be able to hinder the introduction of such compounds into the environment are briefly discussed. 相似文献
9.
Buket Benek Gursoy 《Linear algebra and its applications》2011,435(7):1626-907
We consider the spectral properties of matrix polynomials over the max algebra. In particular, we show how the Perron-Frobenius theorem for the max algebra extends to such polynomials and illustrate the relevance of this for multistep difference equations in the max algebra. We also present a number of inequalities for the largest max eigenvalue of a matrix polynomial. 相似文献
10.