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Tytuł:
Zastosowanie spektroskopii 1H NMR do oceny przebiegu biodegradacji zanieczyszczeń węglowodorowych
Application of 1H NMR spectroscopy in assessment of the course of hydrocarbon contaminant biodegradation
Autorzy:
Śliwka, E.
Kołwzan, B.
Kołodziej, K.
Powiązania:
https://bibliotekanauki.pl/articles/237708.pdf
Data publikacji:
2015
Wydawca:
Polskie Zrzeszenie Inżynierów i Techników Sanitarnych
Tematy:
magnetyczny rezonans jądrowy
produkty naftowe
rozkład biologiczny
oczyszczanie gruntu
nuclear magnetic resonance (NMR)
petroleum substances
coal tar
biological degradation
soil treatment
Opis:
Oceniono przydatność techniki spektroskopii 1H NMR do charakterystyki zmian w strukturze chemicznej substancji naftowych (olej napędowy i ropa naftowa) oraz odpadowej smoły gazowniczej zachodzących w procesie ich biodegradacji. Proces biodegradacji prowadzono przez 14 dób, wykorzystując szczepy bakterii wyizolowane z gleby skażonej produktami naftowymi. Skuteczność biodegradacji była zróżnicowana i w przypadku oleju napędowego wynosiła 89%, ropy naftowej – 45% i smoły gazowniczej – 26%. Analiza widm 1H NMR substratów wykazała duże różnice w rozkładzie protonów alifatycznych i aromatycznych między próbkami naftowymi i smołą gazowniczą. Substraty naftowe charakteryzowały się około 3-krotnie mniejszym współczynnikiem aromatyczności (fA=0,12 i 0,14) oraz wzrostem wartości tego parametru w produktach biodegradacji. Potwierdza to obecność w substancjach naftowych składników alifatycznych, łatwo ulegających biodegradacji. Duże różnice wartości parametru fA wskazują, że może być on wykorzystany do różnicowania źródeł zanieczyszczeń węglowodorowych w próbkach środowiskowych. Dodatkową zaletą techniki 1H NMR jest mała ilość analitów potrzebna do analizy oraz fakt, że należy do grupy badań nieniszczących.
Suitability of 1H NMR spectroscopy for evaluation of changes in chemical structure of petroleum substances (diesel and crude oils) and coal tar waste upon their biodegradation was assessed. Biodegradation was carried out for 14 days using bacterial strains isolated from petroleum-contaminated soil. Biodegradation effectiveness varied, amounting to 89% for diesel oil, 45% for crude oil and 26% for coal tar. 1H NMR spectra analysis demonstrated major differences in the distribution of aliphatic and aromatic protons between petroleum samples and coal tar. The aromaticity factor of petroleum substrates was about 3 times lower (fA=0.12 and 0.14) and it increased in the biodegradation products. This confirms presence of aliphatic components, readily biodegradable, in petroleum substances. Major differences in the fA parameter values indicate that it can be used to differentiate between the sources of hydrocarbon contamination in environmental samples. An additional advantage of the 1H NMR technique is a small amount of analyte required for analysis and the non-destructive character of the technique.
Źródło:
Ochrona Środowiska; 2015, 37, 2; 55-60
1230-6169
Pojawia się w:
Ochrona Środowiska
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Molecular Reorientations οf N-n-Hexyltetrachlorophthalimide Studied by $\text{}^1H$ NMR
Autorzy:
Hołderna-Natkaniec, K.
Jurga, K.
Woźniak-Braszak, A.
Walczak, A.
Powiązania:
https://bibliotekanauki.pl/articles/1538203.pdf
Data publikacji:
2010-04
Wydawca:
Polska Akademia Nauk. Instytut Fizyki PAN
Tematy:
07.05.Tp
31.15.E-
33.20.Ea
64.70.K-
76.60.-k
Opis:
The spin-lattice relaxation times $T_{1}$ and the second moment of $\text{}^{1}H$ NMR line have been employed to study the internal dynamics of protons of N-n-hexyl-tetra-chloro-phthali-mides in the temperature range 80-350 K. The model of internal reorientations has been proposed.
Źródło:
Acta Physica Polonica A; 2010, 117, 4; 537-548
0587-4246
1898-794X
Pojawia się w:
Acta Physica Polonica A
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
$\text{}^{1}$H NMR Study of Molecular Dynamics of 4-apyH Cation under High Hydrostatic Pressure
Autorzy:
Medycki, W.
Świergiel, J.
Jakubas, R.
Hołderna-Natkaniec, K.
Powiązania:
https://bibliotekanauki.pl/articles/2043431.pdf
Data publikacji:
2005-07
Wydawca:
Polska Akademia Nauk. Instytut Fizyki PAN
Tematy:
77.84.-s
76.60.-k
Opis:
Polycrystalline [4-NH$\text{}_{2}$C$\text{}_{5}$H$\text{}_{4}$NH] SbCl$\text{}_{4}$ and [4-NH$\text{}_{2}$C$\text{}_{5}$H$\text{}_{4}$NH] SbCl$\text{}_{6}$ have been investigated by proton NMR methods between 120 K and 370 K under hydrostatic pressure of 0.1 and 520 MPa. Reduction in the dipolar second moment is interpreted in terms of cation reorientation. Activation energies characterizing the motion increase with increasing pressure.
Źródło:
Acta Physica Polonica A; 2005, 108, 1; 161-164
0587-4246
1898-794X
Pojawia się w:
Acta Physica Polonica A
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Application of 1H and 31P NMR to topological description of a model of biological membrane fusion Topological description of a model of biological membrane fusion
Autorzy:
Janiak-Osajca, Agnieszka
Timoszyk, Anna
Powiązania:
https://bibliotekanauki.pl/articles/1039735.pdf
Data publikacji:
2012
Wydawca:
Polskie Towarzystwo Biochemiczne
Tematy:
vesicle
topology
fusion
31P-NMR
1H-NMR
Opis:
The process of biological membrane fusion can be analysed by topological methods. Mathematical analysis of the fusion process of vesicles indicated two significant facts: the formation of an inner, transient structure (hexagonal phase - HII) and a translocation of some lipids within the membrane. This shift had a vector character and only occurred from the outer to the inner layer. Model membrane composed of phosphatidylcholine (PC), phosphatidylethanolamine (PE) and phosphatidylserine (PS) was studied. 31P- and 1H-NMR methods were used to describe the process of fusion. 31P-NMR spectra of multilamellar vesicles (MLV) were taken at various temperatures and concentrations of Ca2+ ions (natural fusiogenic agent). A 31P-NMR spectrum with the characteristic shape of the HII phase was obtained for the molar Ca2+/PS ratio of 2.0. During the study, 1H-NMR and 31P-NMR spectra for small unilamellar vesicle (SUV), which were dependent on time (concentration of Pr3+ ions was constant), were also recorded. The presence of the paramagnetic Pr3+ ions permits observation of separate signals from the hydrophilic part of the inner and outer lipid bilayers. The obtained results suggest that in the process of fusion translocation of phospholipid molecules takes place from the outer to the inner layer of the vesicle and size of the vesicles increase. The NMR study has showed that the intermediate state of the fusion process caused by Ca2+ ions is the HII phase. The experimental results obtained are in agreement with the topological model as well.
Źródło:
Acta Biochimica Polonica; 2012, 59, 2; 219-224
0001-527X
Pojawia się w:
Acta Biochimica Polonica
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
_1H NMR spectra of trypsin inhibitors from seeds of Cucurbitaceae plants. Resonance signals of methyl groups.
Autorzy:
Siemion, Ignacy
Sobczyk, Katarzyna
Wilusz, Tadeusz
Polanowski, Antoni
Powiązania:
https://bibliotekanauki.pl/articles/1046025.pdf
Data publikacji:
1984
Wydawca:
Polskie Towarzystwo Biochemiczne
Źródło:
Acta Biochimica Polonica; 1984, 31, 2; 207-215
0001-527X
Pojawia się w:
Acta Biochimica Polonica
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
$\text{}^1H$ NMR on $(Ni_xMn_{1-x})_3[Cr(CN)_6]_2 \cdot nH_2O$
Autorzy:
Bokor, M.
Tompa, K.
Kiss, L.
Zentková, M.
Zentko, A.
Mihalik, M.
Maťaš, S.
Mitróová, Z.
Powiązania:
https://bibliotekanauki.pl/articles/1813831.pdf
Data publikacji:
2008-01
Wydawca:
Polska Akademia Nauk. Instytut Fizyki PAN
Tematy:
72.80.Ga
75.50.Xx
76.60.Lz
Opis:
We report on $\text{}^1H$ NMR of $(Ni_xMn_{1-x})3[Cr(CN)_6]_2 \cdot 15H_2O$ hexacyanochromates, where x changes from 0 to 1. The decay time constants of the free induction decay signals described by an effective spin-spin relaxation time $T_{2eff}$ obtained from M(t) = $M_0 \text{exp}(t//T_{2eff})$ decrease as the local magnetic moments increase produced by the magnetic transition metal ions at the sites of the resonant $\text{}^1H$ nuclei. The recovery of the magnetization in the spin-lattice relaxation time $(T_1)$ experiments was single-exponential.
Źródło:
Acta Physica Polonica A; 2008, 113, 1; 485-488
0587-4246
1898-794X
Pojawia się w:
Acta Physica Polonica A
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Detection of acylglycines in urine by 1H and 13C NMR for the diagnosis of inborn metabolic diseases
Autorzy:
Gryff-Keller, Adam
Kraska-Dziadecka, Anna
Kubica, Dominika
Powiązania:
https://bibliotekanauki.pl/articles/1039667.pdf
Data publikacji:
2012
Wydawca:
Polskie Towarzystwo Biochemiczne
Tematy:
13C NMR
urinalysis
inherited metabolic disease
1H NMR
acylglycine
Opis:
A range of inborn metabolic diseases result in abnormal accumulation of acylglycines in body fluids. Therefore, detection of these metabolites is important for diagnostic purposes. 1H and 13C NMR spectroscopies have successfully been applied for both qualitative and quantitative determinations of various acylglycines in urine samples from patients suffering from metabolic diseases connected with excretion of these compounds. Various acylglycines were identified in test urine samples from 15 patients suffering from five different metabolic diseases, providing information which could be crucial for their diagnoses. The paper reports complete 1H and 13C NMR data of 11 acylglycines, which is essential for this type of NMR analysis of body fluids. NMR spectroscopy has been proven effective in determining the presence as well as the levels of acylglycines in urine. The proposed method is rapid, simple and requires minimal sample treatment.
Źródło:
Acta Biochimica Polonica; 2012, 59, 4; 613-617
0001-527X
Pojawia się w:
Acta Biochimica Polonica
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Synthesis and anticancer evaluation of some coumarin and azacoumarin derivatives
Autorzy:
Bakare, Safyah B.
Powiązania:
https://bibliotekanauki.pl/articles/1849302.pdf
Data publikacji:
2021
Wydawca:
Zachodniopomorski Uniwersytet Technologiczny w Szczecinie. Wydawnictwo Uczelniane ZUT w Szczecinie
Tematy:
Coumarin
azacoumarin
1H-NMR spectrum
13C-NMR spectrum
anticancer
Opis:
Coumarin and its nitrogen analogue 1-aza coumarin are a class of lactones and lactams, respectively, which are indispensable heterocyclic units to both chemists and biochemists. 1-Aza coumarin derivatives, which ultimately metabolize as the corresponding 8-hydroxy coumarins in the biological system are therefore found to be very good anti-inflammatory, anti-cancer, and analgesic agents. A series of hybrid substituted coumarin and azacoumarin-3-carboxylic acid derivatives (8-methoxycoumarin-3-carboxylic acid (4a), 8-methoxyazacoumarin-3-carboxylic acid (4b), 5-bromo-8-methoxycoumarin-3-carboxylic acid (5a), 5-bromo-8-methoxyazacoumarin-3-carboxylic acid (5b), 2-acetoxy-5-bromo-8-methoxyquinoline-3-carboxylic acid (6), and 5,7-di(phenylazo)-8-methoxycoumarin-3-carboxylic acid (7) were synthesized and structurally proved using spectral and elemental analysis data. Substituted coumarin-3-carboxylic acid (4a and 5a) and Substituted azacoumarin-3-carboxylic acid (4b, 5b and 6) were tested for their in vitro cytotoxic activity against MCF-7 and HepG-2 cell lines.
Źródło:
Polish Journal of Chemical Technology; 2021, 23, 2; 27-34
1509-8117
1899-4741
Pojawia się w:
Polish Journal of Chemical Technology
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Investigation of a wide spectrum of inherited metabolic disorders by 13C NMR spectroscopy
Autorzy:
Bal, Dominika
Kraska-Dziadecka, Anna
Gradowska, Wanda
Gryff-Keller, Adam
Powiązania:
https://bibliotekanauki.pl/articles/1040823.pdf
Data publikacji:
2008
Wydawca:
Polskie Towarzystwo Biochemiczne
Tematy:
urine
13C NMR
inherited metabolic disease
1H NMR
marker metabolite
Opis:
High-resolution 1H NMR spectroscopy of body fluids has proved to be very useful in diagnostics of inherited metabolic diseases, whereas 13C NMR remains almost unexploited. In this paper the application of 13C NMR spectroscopy of fivefold concentrated urine samples for diagnosis of selected metabolic diseases is reported. Various marker metabolites were identified in test urine samples from 33 patients suffering from 10 different diseases, providing information which could be crucial for their diagnoses. Spectra were accumulated for 2 h or overnight when using spectrometers operating at 9.4 or 4.7 T magnetic fields, respectively. Interpretation of the measurement results was based on a comparison of the peak positions in the measured spectrum with reference data. The paper contains a table with 13C NMR chemical shifts of 73 standard compounds. The method can be applied individually or as an auxiliary technique to 1H NMR or any other analytical method.
Źródło:
Acta Biochimica Polonica; 2008, 55, 1; 107-118
0001-527X
Pojawia się w:
Acta Biochimica Polonica
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
$\text{}^{1}$H NMR and Rheological Studies of the Calcium Induced Gelation Process in Aqueous Low Methoxyl Pectin Solutions
Autorzy:
Dobies, M.
Kuśmia, S.
Jurga, S.
Powiązania:
https://bibliotekanauki.pl/articles/2043388.pdf
Data publikacji:
2005-07
Wydawca:
Polska Akademia Nauk. Instytut Fizyki PAN
Tematy:
82.70.Gg
87.15.By
87.15.Rn
82.56.-b
87.15.He
83.10.-y
87.15.La
Opis:
The $\text{}^{1}$H NMR relaxometry in combination with water proton spin-spin relaxation time measurements and rheometry have been applied to study the ionic gelation of 1% w/w aqueous low methoxyl pectin solution induced by divalent Ca$\text{}^{2+}$ cations from a calcium chloride solution. The model-free approach to the analysis of $\text{}^{1}$H NMR relaxometry data has been used to separate the information on the static (β) and dynamic (〈τ$\text{}_{c}$〉) behaviour of the systems tested. The $\text{}^{1}$H NMR results confirm that the average mobility of both water and the pectin molecules is largely dependent on the concentration of the cross-linking agent. The character of this dependency (β,〈τ$\text{}_{c}$〉 and T$\text{}_{2}$ vs. CaCl$\text{}_{2}$ concentration) is consistent with the two-stage gelation process of low methoxyl pectin, in which the formation of strongly linked dimer associations (in the range of 0-2.5 mM CaCl$\text{}_{2}$) is followed by the appearance of weak inter-dimer aggregations (for CaCl$\text{}_{2}$ ≥ 3.5 mM). The presence of the weak gel structure for the sample with 3.5 mM CaCl$\text{}_{2}$ has been confirmed by rheological measurements. Apart from that, the T$\text{}_{1}$ and T$\text{}_{2}$ relaxation times have been found to be highly sensitive to the syneresis phenomenon, which can be useful to monitor the low methoxyl pectin gel network stability.
Źródło:
Acta Physica Polonica A; 2005, 108, 1; 33-46
0587-4246
1898-794X
Pojawia się w:
Acta Physica Polonica A
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
IR and 1H NMR spectral studies of some 2-Amino-4-isopropyl-6-methoxy-N-phenylpyrimidine-5-carboxamides: Assessment of substituent effects
Autorzy:
Arulkumaran, R.
Sundararajan, R.
Manikandan, V.
Sathiyendiran, V.
Pazhamalai, S.
Thirunarayanan, G.
Powiązania:
https://bibliotekanauki.pl/articles/412343.pdf
Data publikacji:
2014
Wydawca:
Przedsiębiorstwo Wydawnictw Naukowych Darwin / Scientific Publishing House DARWIN
Tematy:
2-Amino-4-isopropyl-6-methoxy-N-phenylpyrimidine-5-carboxamides
IR spectra
NMR spectra
substituent effects
Opis:
A series of 2-Amino-4-isopropyl-6-methoxy-N-phenylpyrimidine-5-carboxamide compounds have been synthesized from various substituted dithioacetal and guanidine. The purities of these compounds were checked by their physical constants, UV, IR, NMR and MASS spectral data. The IR and 1HNMR spectral data of these compounds have been correlated with Hammett sigma constants, F and R parameters using single and multi-linear regression analysis. From the results of statistical analysis, the effects of substituents on the spectral group frequencies have been discussed.
Źródło:
International Letters of Chemistry, Physics and Astronomy; 2014, 19, 1; 15-25
2299-3843
Pojawia się w:
International Letters of Chemistry, Physics and Astronomy
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Translocation of polysialic acid across model membranes: Kinetic analysis and dynamic.
Autorzy:
Janas, Teresa
Krajiński, Henryk
Timoszyk, Anna
Janas, Tadeusz
Powiązania:
https://bibliotekanauki.pl/articles/1044181.pdf
Data publikacji:
2001
Wydawca:
Polskie Towarzystwo Biochemiczne
Tematy:
polysialic acid
1H-NMR
electrical equivalent circuit
polycation flux
polyanion flux
lipid bilayers
membrane transport
Opis:
Transmembrane translocation of polyion homopolymers takes place in the case of polyanionic polysialic acid (polySia), polyanionic polynucleotides and polycationic polypeptides. The purpose of this work was to determine the role of membrane electrical parameters on the kinetics of polyion translocation, the influence of polysialic acid on ion adsorption on positively charged membrane surface and the dynamics of the phospholipid hydrocarbon chains and choline group by using 1H-NMR. The analysis of polyion translocation was performed by using the electrical equivalent circuit of the membrane for the initial membrane potential equal to zero. The changes in polysialic acid flux was up to 75% after 1 ms in comparison with the zero-time flux. Both a decrease of membrane conductance and an increase of polyion chain length resulted in the diminution of this effect. An increase of praseodymium ions adsorption to positively charged liposomes and an increase of the rate of segmental movement of the -CH2 and -CH3 groups, and the choline headgrup of lipid molecules, was observed in the presence of polySia. The results show that the direction of the vectorial polyion translocation depends both on the membrane electrical properties and the degree of polymerization of the polymer, and that polysialic acid can modulate the degree of ion adsorption and the dynamics of membrane lipids.
Źródło:
Acta Biochimica Polonica; 2001, 48, 1; 163-173
0001-527X
Pojawia się w:
Acta Biochimica Polonica
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Application of 1H-NMR relaxometry to the determination of the water content in clay soils
Zastosowanie metody NMR do określenia wilgotności w gruntach spoistych
Autorzy:
Nartowska, E.
Kozłowski, T.
Kolankowska, M.
Powiązania:
https://bibliotekanauki.pl/articles/402547.pdf
Data publikacji:
2015
Wydawca:
Politechnika Świętokrzyska w Kielcach. Wydawnictwo PŚw
Tematy:
water content
clay soils
NMR methods
FID Signal
wilgotność
grunty spoiste
metody NMR
sygnał FID
Opis:
The NMR technique is widely used in polymer, chemical, and agrifood industries, as well as in many other fields of science and technology. This work presents results from the use of FID (Free Induction Decay) application to determine the water content in clay soil samples. The widely used oven-drying method is time-consuming and precludes using the same sample to another test, because drying process damages the internal structure of soil. Three clay soils, characterized by high surface area, were used in the research and six to eight samples for each soil were tested. The obtained dependence curve between FID Signal Intensities and mass of water was characterized by a high correlation coefficient (R2 = 0.97). The curve can be used to determine the mass of water present in clay soil sample on the basis of FID Signal Intensity. Such approach allows 1H-NMR relaxometry to be applied for the determination of water content in soil samples in a fast and non-destructive way.
Źródło:
Structure and Environment; 2015, 7, 4; 189-193
2081-1500
Pojawia się w:
Structure and Environment
Dostawca treści:
Biblioteka Nauki
Artykuł
Wyświetlanie 1-15 z 37

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