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1.
Graphene multilayers have been prepared by mechanical method based on milling graphite in high efficient attritor mill. The
results showed that the best dispersion media is ethanol, and 10 hours of intensive milling proved to be the most efficient
way to separate the graphite layers as it was shown by scanning electron microscopy and X-ray diffraction measurements.
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2.
Chiral aminosulfonamides containing imidazolium group were used as ligands for the ruthenium(II)-catalyzed asymmetric transfer
hydrogenation of prochiral ketones in ionic liquid, affording good to excellent conversions and enantiomeric excesses. The
catalytic system could be easily recovered and reused several times.
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4.
Pavel Diviš Roman Szkandera Hana Dočekalová 《Central European Journal of Chemistry》2010,8(5):1105-1109
The influence of pH, ionic strength and selected natural ligands on the measurement of mercury by the diffusive gradients
in thin films technique (DGT) using recently introduced sorption gels was determined. Sorption gels containing Chelex 100,
Spheron-Thiol, Duolite GT73 and modified Iontosorb AV resins were investigated, with the sorption capacity determined for
all used sorption gels. The minimum DGT measurable concentrations were calculated from 3 times the standard deviation of mercury
amount in unexposed sorption gels.
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5.
6.
Zhen-Yu Jiang Ji-Rong Wu Li Li Xi-Huai Chen Guo-Qiao Lai Jian-Xiong Jiang Yixin Lu Li-Wen Xu 《Central European Journal of Chemistry》2010,8(3):669-673
Lewis acid-assisted Br?nsted acid (LBA) catalysis was proposed for the iron-catalyzed Friedel-Crafts alkylation of indoles
with chalcones. This proposal was supported by the ESI-MS and cyclic voltammetry. The addition of acac to the iron-catalyzed
Friedel-Crafts alkylation of indoles with chalcones created a powerful catalytic system, which makes the alkylation reactions
occur easily under mild conditions.
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7.
Ramin Ghorbani-Vaghei Seyedeh Mina Malaekehpour 《Central European Journal of Chemistry》2010,8(5):1086-1089
N,N,N,’N’-Tetrabromobenzene-1,3-disulfonamide [TBBDA] is found to be a reusable catalyst for efficient synthesis of various amidoalkyl
naphthols from β-naphthol, aromatic aldehydes and urea in good to high yields under solvent-free conditions.
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8.
Rayna Bryaskova Nelly Georgieva Dimitar Peshev 《Central European Journal of Chemistry》2010,8(5):1053-1058
Polyvinyl alcohol (PVA) and tetraethoxysilane (TEOS) hybrid materials were prepared by sol-gel methods and tested as matrices
for immobilization of Trichosporon cutaneum R57, capable of removing cadmium and copper ions from aqueous solutions. A kinetic model was applied and the effects of matrix
TEOS content on the copper and cadmium uptake equilibria and rate constants were investigated.
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9.
Gréta Gergely Ferenc Wéber István Lukács Levente Illés Attila L. Tóth Zsolt E. Horváth Judit Mihály Csaba Balázsi 《Central European Journal of Chemistry》2010,8(2):375-381
Hydroxyapatite (HAp) was successfully produced from recycled eggshell, seashell and phosphoric acid. The phases obtained depended
on the ratio of calcined eggshell/ seashell to phosphoric acid, the calcination temperature and the mechanochemical activation
method (ball milling or attrition milling). The HAp structures were characterized by X-ray diffraction, scanning electron
microsopy and infrared spectroscopy. Attrition milling was more effective than ball milling, yielding nanosize, homogenous
and pure Hap.
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10.
Mehdi Ghandi Parham Asgari Abuzar Taheri Alireza Abbasi 《Central European Journal of Chemistry》2010,8(4):899-905
One-pot, three-component condensation of 2-hydroxybenzaldehyde derivatives, primary amines with alkyl isocyanides is reported.
N-alkyl-2-(2-hydroxyphenyl)-2-iminoacetamide derivatives are generated presumably via the preliminary formation of N, N′-disubstituted benzo[b]furan-2,3-diamines and subsequent oxidation with molecular oxygen.
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11.
Yevgen Karpichev Hubert Matondo Illia Kapitanov Oleksandr Savsunenko Marc Vedrenne Verena Poinsot Isabelle Rico-Lattes Armand Lattes 《Central European Journal of Chemistry》2012,10(4):1059-1065
A simple and efficient protocol for the preparation of a series of N-alkyl-3-boronopyridinium salts is described which requires exposure of 3-pyridineboronic acid neopentylglycol ester and corresponding alkyle halide to microwave irradiation followed by boronic ester hydrolysis. The technique employed drastically reduces the reaction time and prevents thermal degradation and the formation of side products. Water solutions of the obtained boronopyridinium salts are shown to be stable at room temperature in wide pH range as well as in the presence of hydrogen peroxide at pH 10.0 for 72 h. 相似文献
12.
Ivan M. Savic Goran S. Nikolic Ivana M. Savic Milorad D. Cakic 《Central European Journal of Chemistry》2010,8(5):1078-1085
Bioactive copper complexes with pullulan or dextran oligosaccharides are the subject of intensive research mainly because
of their possible application in veterinary and human medicine. The thermal stability and stability under oxidative conditions
of the Cu(II) complexes with reduced low-molar pullulan or dextran were investigated in this paper, using a conductometric
method. The influence of ligand constitutions on the stability of the complexes was examined on the basis of ligand property.
Forced degradation studies were performed on bulk sample of complexes by using heat (25, 40 and 60°C) and an oxidation agent
(0.1, 0.5, 1.0 and 10.0% v/v hydrogen peroxide). It can be concluded, according to the results obtained (by examining conductivity
during the forced degradation studies), that Cu(II) complexes show a large pharmaceutical stability for both tests.
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13.
Titania layers obtained by a sol-gel technique doped with redox mediator, Meldola’s Blue, were employed for construction of
a new NADH senor. Optimization of preparation process as well as experimental conditions affecting the response of the sensor
were examined. Under optimal conditions NADH could be determined in the wide linear range from 90 to 2300 μM with detection
limit 12 μM and a high sensitivity 12.5 nA μM−1. The usefulness of developed sensor was preliminarily checked in determination of NADH forming during enzymatic oxidation
of ethanol catalyzed by alcohol dehydrogenase (ADH).
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14.
Nadezhda Rangelova Lachezar Radev Sanchi Nenkova Isabel M. Miranda Salvado Maria H. Vas Fernandes Michael Herzog 《Central European Journal of Chemistry》2011,9(1):112-118
Methylcellulose (MC) / SiO2 organic / inorganic hybrid materials have been prepared from MC and methyltriethoxysilane or ethyltrimethoxysilane, and characterized
by XRD, FTIR and AFM. XRD showed peak shifts. FTIR shows intermolecular hydrogen bonding between MC and SiO2. AFM depicts surface roughness which depends on the silica precursor and MC content.
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15.
Iwona Binkowska Włodzimierz Gałęzowski Arnold Jarczewski 《Central European Journal of Chemistry》2010,8(3):582-586
Proton transfer reactions rates between carbon acids 1-nitro-1-(4-nitrophenyl)ethane (NPNE), 2-methyl-1-nitro-1-(4-nitrophenyl)propane
(MNPNP)) and phosphazenes (BEMP, BTPP, P1-t-Oct) in tetrahydrofuran have been measured, and the activation parameters were determined. The results are compared with
those previously obtained for P1-t-Bu phosphazene, guanidines and amidines.
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16.
The Diels-Alder reaction between cyclopentadiene and dienophiles in deanol derivatives containing bis(trifluoromethylsulfonyl)imide
anion as media have been studied. The effect of the substituents attached to the cation on the endo:exo selectivity as well
as the reaction yield have been evaluated in the absence and presence of Lewis acid catalyst - Y(OTf)3. Catalytic activity of metal triflates and the recycling of chosen catalytic systems have also been investigated
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17.
Santosh S. Katkar Pravinkumar H. Mohite Lakshman S. Gadekar Balasaheb R. Arbad Machhindra K. Lande 《Central European Journal of Chemistry》2010,8(2):320-325
A rapid and an efficient one-pot method for the synthesis of quinoxalines catalysed by ZnO-beta zeolite at room temperature
is described. This environmentally benign method provides several advantages over methods that are currently employed such
as a simple work-up, mild reaction conditions, good to excellent yields, and a process to recover and reuse the catalyst for
several cycles with consistent activity.
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18.
Irena Baranowska Sylwia Magiera Jacek Baranowski 《Central European Journal of Chemistry》2011,9(6):972-981
The aim of this paper is to optimize and validate a high performance liquid chromatography (HPLC) method for separation and
quantification of five isoflavones. A statistical central composite design was used to separate all peaks. These multivariate
procedures were efficient in determining the optimal separation condition using resolution, capacity factor, asymmetry and
number of theoretical plates.
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19.
Silica gel was chemically modified with Congo red and characterized by Fourier transform infrared spectroscopy, elemental
and thermogravimetric analysis. The pH-sensitive immobilized Congo red retains the same properties as its solution counterpart
and could be applied as solid indicator. The functionalized silica gel was also employed to extract different cations from
water solutions. The concentration of cations extracted was determined by inductively coupled plasma optical emission spectrometry.
The solid support is able to selectively extract silver and copper from water solutions and retains its properties after treatment
with different organic and inorganic solvents.
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20.
Jorge García-Barrasa José M. López-de-Luzuriaga Miguel Monge 《Central European Journal of Chemistry》2011,9(1):7-19
Chemical methods provide an easy way to synthesize silver nanoparticles (Ag NPs) in solution. These metal nanoparticles have
a great potential for biomedical applications as an antibacterial, antifungal, and antiviral agent or in wound healing. The
adjustment of the parameters involved in these reactions permits a precise control over the size, shape, monodispersity, and
the surfaces of the nanoparticles. These nanoparticles are being used in the design of new hybrid organic-inorganic or inorganic
nanomaterials for biomedical applications.
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