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31.
Sabri Cevik Bihter Şaşmaz Cengiz Yenikaya Ferdağ Çolak Musa Sari Orhan Büyükgüngör 《Russian Journal of Inorganic Chemistry》2010,55(4):494-500
The hydrothermal reaction of a mixture of V2O5, VCl3, 2,5-pyridinedicarboxylic acid and diluted H2SO4 for 68 h at 180°C gives a blue colored solution which yields prismatic blue crystals of IV 2 IV O2(SO4)2(H2O)6] (1) in 32% yield (based on V). Complex 1 was investigated by means of elemental analysis (C, H and S), TGA, FT-IR, manganometric titration, Single Crystal X-ray Diffraction Methods and also comparative antimicrobial activities. Crystal data for the compound: monoclinic space group P21/c and unit cell parameters are a = 7.3850(12) Å, b = 7.3990(7) Å, c = 12.229(2) Å, β = 108.976(12)° and Z = 2. Although structure of 1 as a natural mineral has been previously determined, this work covers new preparation method and full characterization of 1 along with comparison of antibacterial activity between 1 and the commercial vanadium(IV) oxide sulfate hydrate compounds, VOSO4 · xH2O (Riedel-de Haën and Alfa Aesar brand names). 1 was evaluated for the antimicrobial activity against gram-positive, gram-negative bacteria, yeasts and mould compared with the commercial VOSO4 · xH2O compounds. 1 showed weak activity against bacteria Bacillus cereus, Nocardia asteroides and yeast Candida albicans. A good antimicrobial activity was recorded against Cirtobacter freundii (15 mm). There are only a few reproducible well-defined vanadium(IV) starting materials to use for exploring the synthesis of new materials. VCl4, VO(acac)2, VOSO4 · xH2O and [V(IV)OSO4(H2O)4] · SO4 · [H2N(C2H4)2NH2] are common starting materials for such applications. In addition to these compounds, 1 can be used as an oxovanadium precursor. 相似文献
32.
Yalcin S Gurler O Akar UT Incirci F Kaynak G Gundogdu O 《Isotopes in environmental and health studies》2011,47(4):438-445
Concentration of (222)Rn was determined in selected natural spring and tap water samples collected during spring and summer seasons from Kastamonu, Turkey. The aim of this work was to produce a map of the radon concentrations in water sources of the province and to determine any potential radiological risk for the local population. Radon measurements were performed by an AlphaGUARD radon gas analyser. The average radon concentrations were found to vary from 0.39±0.02 to 12.73±0.39?Bq?l(-1) for natural springs and from 0.36±0.04 to 9.29±0.45?Bq?l(-1) for tap water in spring, from 0.50±0.09 to 19.21±1.00?Bq?l(-1) for natural springs and from 0.31±0.03 to 13.14±0.38?Bq?l(-1) for tap water in summer. Furthermore, the results are compared with international recommendations and concentrations reported for other countries. Doses resulting from the consumption of these waters were calculated. The effective dose equivalents due to the intake of the (222)Rn present in these waters are expected to range from 0.93 to 32.54?μSv?y(-1) in summer and from 0.80 to 49.09?μSv?y(-1) in spring. 相似文献
33.
In the present paper we introduce a new concept of $A$ -distributional convergence in an arbitrary Hausdorff topological space which is equivalent to $A$ -statistical convergence for a degenerate distribution function. We investigate $A$ -distributional convergence as a summability method in an arbitrary Hausdorff topological space. We also study the summability of spliced sequences, in particular, for metric spaces and give the Bochner integral representation of $A$ -limits of the spliced sequences for Banach spaces. 相似文献
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35.
Murat Cakici Mustafa Catir Semistan Karabuga Hamdullah Kilic Sabri Ulukanli Medine Gulluce Furkan Orhan 《Tetrahedron: Asymmetry》2010,21(16):2027-2031
A simple synthetic method for the preparation of enantiomerically pure (S)-4-aminoquinazoline alcohols from (S)-quinazolinone alcohols by key steps including chlorination, nucleophilic ipso substitution, and deacetylation is presented. Mutagenic and antimutagenic properties of the (S)-4-aminoquinazoline alcohols were investigated by using Salmonella typhimurium TA1535, and Escherichia coli WP2uvrA tester strains at 0.01, 0.1, and 1 μg/plate concentrations. (S)-4-aminoquinazoline alcohols were found to be genotoxically safe at the tested concentrations. Among the tested (S)-4-aminoquinazoline alcohols, the best antimutagenic activity was obtained with a methyl derivative at 0.1 μg/plate dose. 相似文献
36.
Gökhan Alpaslan Mustafa Macit Ahmet Erdönmez Orhan Büyükgüngör 《Structural chemistry》2011,22(3):681-690
The Schiff base compound (Z)-1-((4-phenylamino)phenylamino)methylene)naphthalen-2(1H)-one has been synthesized and characterized by IR, UV–Vis, and X-ray single-crystal determination. Molecular geometry from
X-ray experiment of the title compound in the ground state have been compared using the Hartree–Fock (HF) and density functional
method (B3LYP) with 6−31G(d,p) basis set. Calculated results show that density functional theory DFT and HF can well reproduce
the structure of the title compound. Using the time-dependent density functional theory (TD-DFT) and Hartree–Fock (TD-HF)
methods, electronic absorption spectra of the title compound have been predicted and a good agreement with the TD-DFT method
and experimental ones is determined. The energetic behavior of the title compound in solvent media has been examined using
B3LYP method with the 6−31G(d,p) basis set by applying the polarizable continuum model (PCM). The total energy of the title
compound decreases with increasing polarity of the solvent. In addition, DFT calculations of the title compound, molecular
electrostatic potential (MEP), natural bond orbital analysis (NBO), and non-linear optical (NLO) properties were performed
at B3LYP/6−31G(d,p) level of theory. 相似文献
37.
38.
Preparation and thermal characterization of poly(2‐vinylpyridine) copolymers coordinated to Cr nanoparticles 下载免费PDF全文
In this study, polystyrene‐block‐poly(2‐vinylpyridine), PS‐b‐P2VP, polyisoprene‐block‐poly(2‐vinylpyridne), PI‐b‐P2VP and poly(methyl metacrylate)‐block‐poly(2‐vinylpyridine), PMMA‐b‐P2VP, coordinated to Cr metal were synthesized and characterized by Fourier transform infrared, transmission electron microscopy and direct pyrolysis mass spectrometry techniques. Both thermal degradation mechanism and thermal stability of P2VP blocks were affected by the coordination of Cr nanoparticles to nitrogen of pyridine rings. Thermal decomposition of P2VP blocks was started by loss of pyridine units leaving an unsaturated and/or crosslinked polymer backbone that degraded at relatively high temperatures. Incorporation of Cr metal did not noticeably influence thermal behavior of PS and PI blocks. However, increase in thermal stability of PMMA block was detected and associated with inhibition of the interactions between carbonyl groups of MMA chains with nitrogen atom of pyridine ring as a consequence of coordination to metal. Copyright © 2015 John Wiley & Sons, Ltd. 相似文献
39.
40.
Rogge WF Ondov JM Bernardo-Bricker A Sevimoglu O 《Analytical and bioanalytical chemistry》2011,401(10):3069-3082
As part of the Baltimore PM2.5 Supersite study, intensive three-hourly continuous PM2.5 sampling was conducted for nearly
4 weeks in summer of 2002 and as well in winter of 2002/2003. Close to 120 individual organic compounds have been quantified
separately in filter and polyurethane foam (PUF) plug pairs for 17 days for each sampling period. Here, the focus is on (1)
describing briefly the new sampling system, (2) discussing filter/PUF plugs breakthrough experiments for semi-volatile compounds,
(3) providing insight into phase distribution of semi-volatile organic species, and (4) discussing the impact of air pollution
sampling time on human exposure with information on maximum 3- and 24-h averaged ambient concentrations of potentially adverse
health effects causing organic pollutants. The newly developed sampling system consisted of five electronically controlled
parallel sampling channels that are operated in a sequential mode. Semi-volatile breakthrough experiments were conducted in
three separate experiments over 3, 4, and 5 h each using one filter and three PUF plugs. Valuable insight was obtained about
the transfer of semi-volatile organic compounds through the sequence of PUF plugs and a cut-off could be defined for complete
sampling of semi-volatile compounds on only one filter/PUF plug pair, i.e., the setup finally used during the seasonal PM2.5
sampling campaign. Accordingly, n-nonadecane (C19) with a vapor pressure (vp) of 3.25 × 10−4 Torr is collected with > 95% on the filter/PUF pair. Applied to phenanthrene, the most abundant the PAH sampled, phenanthrene
(vp, 6.2 × 10−5 Torr) was collected completely in wintertime and correlates very well with three-hourly PM2.5 ambient concentrations. Valuable
data on the fractional partitioning for semi-volatile organics as a function of season is provided here and can be used to
differentiate the human uptake of an organic pollutant of interest via gas- and particle-phase exposure. Health effects studies
often relay on PM2.5 exposure measurements taken over 24 h or longer. We found that maximum 3-h concentrations are frequently
two to five times higher than that found for maximum 24-h concentrations, an important aspect when considering that short-term
exposure to higher air pollution levels are more likely to overpower defense mechanisms in the human lung with subsequent
adverse effects even at lower pollutant levels. 相似文献