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  1. 34 Polish Journal of Chemistry
  2. 10 Bulletin of the Polish Academy of Sciences. Chemistry
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  1. 8 Gryff-Keller A.
  2. 7 Klaja J.
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  4. 5 Molchanov S.
  5. 4 Jarzyna J.
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1
Content available Semi-quantitative analysis study of the impact of microwave treatment on fly ash
Ma Xian Yun, Nie Yi Miao, Guo Jia Le, Chen Yang, Chang Zhen Jia, Wang Ling, Liu Shu Xian, Wang Long
Physicochemical Problems of Mineral Processing
|
2023
|
Vol. 59, iss. 6
art. no. 174897
EN
Pre-processing provides an effective way for fly ash's high value-added utilization. However, the shortcomings of pre-processing methods such as grinding and flotation are apparent with many disadvantages that make it more challenging to use efficiently. Microwave heating helps the SiO2-Al.2O3 bond break, not only can make the structural change of the material can also promote the chemical reaction process. In the article, XRD, SEM, FT-IR, ammonia nitrogen adsorption, and other methods were used to analyze the changes in the properties of fly ash before and after microwave pre-treatment, the change in adsorption performance of fly ash before and after microwave treatment was analyzed. The study found that under microwave conditions of 600 W and 15 min, the adsorption rate of ammonia nitrogen by fly ash reached a maximum of 29.67%. The intensity of mullite and amorphous diffraction peaks decreased after 20 min at 600 W. The Si-O-(Si, Al) and Si-O-(Si) bonds showed significant changes at 15 min and 20 min under 600 W conditions. Based on the results, the microwave conditions were selected at 600 W for different periods, and semi-quantitative analysis was carried out by XRD-Rietveld, infrared peak fitting, and nuclear magnetic resonance. The XRD-Rietveld analysis showed that the amorphous phase content reached 46.18% at 15 min. In the infrared peak fitting, the fitting area at 1300-900 cm-1 and 600-400 cm-1 peaks at 56.92% at 25 min and 17.5% at 15 min, respectively. The silicon-oxygen network's degree of connection and polymerization was reduced after 15 min of microwave treatment for the nuclear magnetic resonance analysis. By combining specific surface area measurements, it was discovered that the maximum specific surface area attained a value of 3.122 m2/g at 15 min.
2
Content available Wzmocnienie sygnału magnetycznego rezonansu jądrowego metodami hiperpolaryzacji jądrowej ze szczególnym uwzględnieniem hiperpolaryzacji indukowanej parawodorem
Jopa Sylwia, Mames Adam, Ratajczyk Tomasz
Wiadomości Chemiczne
|
2022
|
[Z] 76, 11-12
912--942
EN
Nuclear Magnetic Resonance based methods are currently being widely utilized in many fields of science, medicine, and industry. The impressive amount of success that has been made with NMR has been possible because an enormous effort has been expended to improve the low level of NMR sensitivity. However, the issue of low NMR sensitivity is still a serious problem, and NMR still cannot be utilized in many important cases where the concentrations of NMR active species are low-this is why the boosting of the NMR signal is currently one of the most important research fields in the NMR area. Here, the problem of low NMR sensitivity is discussed through the presentation of methodologies aimed at increasing NMR sensitivity and their novel applications. First, a short general overview of the NMR and its sensitivity problem will be presented. Having clearly identified the problem, the main technologies that will be utilized for the improvement of NMR sensitivity will be introduced. First, we will concisely, and with appropriate references, present methodologies that can increase NMR sensitivity via the design of novel superconducting magnets, the application of cryotechnology for the design of noiseless probe heads, and other hardware and software approaches. Next, the most promising and powerful method for NMR signal enhancement which is known as hyperpolarization will be discussed. First, noble gas hyperpolarization and CIDNP will be briefly presented. We will describe the basic mechanism and applications of these methods. Next, our attention will be paid to the DNP approach, and the origin and applications of the DNP effect will be presented, in particular from the point of view of its utilization in medical diagnostics and material sciences. The most extensive part of our discussion will be devoted to the parahydrogen-based methods, which include hydrogenable Parahydrogen Induced Polarization and Signal Amplification by Reversible Exchange. In the introduction to these methods, the properties of hydrogen molecules, which are the main driving forces of PHIP, will be presented. The mechanism of the boosting of NMR signals will be presented for hPHIP and SABRE. The application of these methods will be presented, with the central focus being on their applications in catalysis and medical diagnostics. In the context of medical applications, the hyperpolarization of biorelevant molecules will be presented. Finally, a summary and future prospects for the development of methods of NMR signal enhancement, particularly in the context of hyperpolarization, will be discussed.
3
Content available Monitorowanie metabolizmu komórkowego za pomocą metody spektroskopii NMR
Pudełko-Malik Natalia, Sapeta Monika, Młynarz Piotr
Wiadomości Chemiczne
|
2022
|
[Z] 76, 5-6
323--333
EN
Metabolomics approaches allow systematic identification and quantitation of all metabolites in biological samples analyzes. As already known metabolism is directly or indirectly related to every aspect of cell function, therefore a careful observation of every changes taking place in metabolism, for example endogenous biochemical reaction products, reflectsthe phenotype of any living cell. Monitoring the metabolite profiles using metabolomics technologies, especially nuclear magnetic resonance (NMR) spectroscopy based on cell culture, allows us to evaluate drug efficiency and outcome of experimental therapy, and most importantly, it allows us to monitor the reaction of the model cell lines to a given treatment. The continued development of metabolomic approaches, e.g. analytical technique, or chemometric software, will accelerate the widespread use of metabolomics not only in the clinical field but also in different biological fields. This work presents a use of nuclear magnetic resonance to characterize and understand the cellular metabolome in a wide range of pathophysiological and clinical contexts.
4
Content available Oznaczanie związków fosforu w matrycach roślinnych
Żyszka-Haberecht Beata, Wieczorek Dorota, Lipok Jacek
Wiadomości Chemiczne
|
2021
|
[Z] 75, 7-8
1017--1038
EN
The variety of the chemical forms of phosphorus compounds occurring in plant tissues, accompanied by the complexity of the chemical composition of plants as the analytical matrices, are the reasons why there is no one, the best answer, how those individual substances may be determined qualitatively and quantitatively. Interestingly, if the subject of determination is the total phosphorus content, the spectrum of effective methods and techniques seems to be impressive. However, in case of spectrophotometric measurements and classical variants of absorption (FAAS) or emission (ICP-AES/ ICP-OES) spectrometry techniques, it is necessary at first to isolate various phosphorus forms from the matrix, and then to mineralize them prior determination. The development of combined methods e.g. ETV-ICP- AES or HR-ETAAS, does allow the isolation of the phosphorus analyte and its detection in a kind of “one step” analytical procedure, directly in plant tissues. Similar benefits, while maintaining the sensitivity of determinations, are brought by the use of XRF, SIMS or nanoSIMS - more expensive techniques of imaging the presence of phosphorus in biological matrices. In turn, the application of nuclear magnetic resonance spectroscopy, especially the 31P NMR technique is thought to be the most universal approach. Using this technique and being aware of higher limit of detection, it is possible to determine various plant phosphorus compounds qualitatively and quantitatively, at the same time.
5
Content available Application of low-field NMR in the study of flocculant-aided filtration process of coal tailings
Guo Zhimin, Liang Long, Hu Pengfei
Physicochemical Problems of Mineral Processing
|
2021
|
Vol. 57, iss. 3
1--7
EN
Preconditioning of coal tailings with flocculants is a useful technology to improve filtration performance. In this study, anionic and cationic polyacrylamides were used for the pretreatment coal tailings before filtration. Nondestructive and rapid measurement of the filter cakes of coal tailings at different filtration stages was conducted using a nuclear magnetic resonance (NMR). The transverse relaxation time (T2) results of NMR provided the information concerned the state of water in filter cake, showing that free water entrapped in larger pores was removed mainly during coal tailings filtration, and the pressure in this study cannot remove the inherent moisture of filter cake of coal tailings. The significant increase in the amplitude of T2 value between 0.1 and 1.0 ms revealed that the flocs collapsed into smaller ones with water entrapped in them during filtration. Comparing the NMR results with different flocculants shows that anionic polyacrylamide of 800 g/Mg produced a larger structure in the initial stage of filter cake formation. The final filter cake entrapped more water. The NMR results well validated the filtration experiments.
6
Content available Ocena przydatności wykorzystania geometrycznych parametrów przestrzeni porowej z obrazów tomograficznych w kontekście pomiarów NMR, porozymetrii rtęciowej i porozymetrii helowej
Drabik Katarzyna, Krakowska-Madejska Paulina, Puskarczyk Edyta, Dohnalik Marek
Nafta-Gaz
|
2021
|
R. 77, nr 11
725--735
PL
Głównym celem pracy była ocena przydatności wyników interpretacji ilościowej, uzyskanej z obrazowania wewnętrz­nej struktury próbek skał z wykorzystaniem metody tomografii komputerowej, do szacowania parametrów zbiornikowych takich jak porowatość czy przepuszczalność. W pracy badano zależności korelacyjne pomiędzy parametrami przestrzeni porowej uzyskanymi z analizy obrazów tomografii komputerowej a wynikami standardowych badań laboratoryjnych. Materiał badawczy składał się z próbek piaskowców czerwonego spągowca, facji eolicznej, pobranych z obszaru Niżu Polskiego. Do analiz wybrano kilkadziesiąt próbek skał piaskowców czerwonego spągowca, dla których policzono 69 parametrów. Interpretacja jakościowa i ilościowa polegała na porównaniu parametrów otrzymanych z analizy obrazu tomograficznego z wcześniej uzyskanymi wynikami analiz laboratoryjnych obejmujących następujące metody badawcze: porozymetrię helową (Por.He), spektrometrię jądrowego rezonansu magnetycznego (NMR), porozymetrię rtęciową (Por.Hg) i przepuszczalność absolutną (przepuszcz). Utworzono macierze korelacji dla wszystkich dostępnych parametrów, do pracy wybrano korelacje istotne, o najwyższym współczynniku korelacji liniowej. Zaobserwowano istotne zależności liniowe pomiędzy parametrami wyznaczonymi z analizy obrazów CT i innych metod badawczych. Uzyskano modele pozwalające na szacowanie przepuszczalności, porowatości i zawartości wody nieredukowalnej na podstawie parametrów geometrycznych otrzymanych z obrazów tomograficznych (współczynnik kształtu, charakterystyka Eulera czy powierzchnia właściwa). W efekcie możliwe jest wstępne oszacowanie parametrów petrofizycznych jedynie na bazie wyników z nieniszczącej metody CT. W przypadku obrazowania tomograficznego pełnych rdzeni uzyskane związki pozwalają na wstępną estymację rozkładu porowatości i gęstości objętościowej w całym rdzeniu, co może być pomocne podczas typowania miejsc do poboru próbek rdzeni przeznaczonych do szczegółowych badań laboratoryjnych.
EN
The main purpose of the study was to assess the usefulness of the results of quantitative interpretation of computed tomography (CT) images of rocks’ pore structure for the estimation of reservoir parameters, such as porosity and permeability. This study presents results of correlation analyses between the pore space parameters obtained from the analysis of computed tomography images and the results of standard laboratory tests. The research material consisted of samples representing Rotliegend sandstones of aeolian facies, collected from core material from wells located in the Fore-Sudetic Monocline. Several dozen samples were selected for analysis, for which 69 parameters were calculated. The qualitative and quantitative interpretation consisted in comparing the parameters obtained from the analysis of the tomographic images with the previously obtained results of laboratory analyzes including the following research methods: helium porosimetry (Por.He), nuclear magnetic resonance spectrometry (NMR), mercury porosimetry (Por.Hg) and absolute permeability (let it pass). Correlation matrices for all available parameters were determined, significant correlations with the highest coefficient of linear correlation were selected as a subject of this work. Significant linear relationships were observed between the parameters determined from the analysis of CT images and other research methods. Models that were obtained allowed to estimate the permeability, porosity, and irreducible water content based on geometrical parameters obtained from tomographic images (shape factor, Euler characteristic or specific surface area). The important result of this work is the possibility to estimate petrophysical parameters based on the results of the non-destructive CT method only. In the case of tomographic imaging of whole cores, the obtained results allow for a preliminary estimation of the porosity and volume density distribution in the entire core, which may be helpful in selecting representative samples of core for detailed laboratory tests.
7
Content available remote Efects of high-temperature thermal treatment on the porosity of red sandstone: an NMR analysis
Zhang He, Sun Qiang, Jia Hailiang, Dong Zhihao, Luo Tao
Acta Geophysica
|
2021
|
Vol. 69, no. 1
113--124
EN
High temperatures afect the physical properties of red sandstone seriously, especially the pores. Understanding its mechanism is of great signifcance in coal mining following underground gasifcation, geothermal energy utilization, and the deep burial of nuclear waste. Nuclear magnetic resonance (NMR) was used to detect pore structure characteristics, and scanning electron microscopy (SEM) and polarizing light microscopy (PLM) were used to mechanism of change. The transverse relaxation time (T2) and signal strengths of red sandstone treated at various temperatures were observed by NMR, and then, the pore situation can be obtained, and fnally, the infuence of temperature on the pore structure of red sandstone can be obtained. Microscopic photographs of the pores of red sandstone were obtained by SEM and PLM to assist in explaining the process of microstructural change, especially the infuences of temperature on pore characteristics and grain morphology and distribution. The researches indicate that after the heat treatment of red sandstone at 25–1300 °C, the pore and strength characteristics change in well-defned stages. Before 500 °C, the pore diameters and distribution range increase, but the porosity and internal grain structure do not change signifcantly. At 500–1000 °C, red sandstone micropores contract, mesopores and macropores develop, and strength decreases. After 1000 °C, the grains that comprise sandstone melt and fll many of the pores, decreasing porosity. The proportion of micropores decreases, while mesopores and macropores increase. In addition, a large number of bubbly holes appear in and on the sandstone, presumably caused by gases such as CO2, and water vapor from dehydrating grains. The changes in pore and cementation states with temperature are the main factors afecting the tensile strength of red sandstone.
8
Content available Biotypowanie mikroorganizmów za pomocą spektrometrii mas oraz spektroskopii NMR
Mielko Karolina Anna, Młynarz Piotr
Wiadomości Chemiczne
|
2020
|
[Z] 74, 1-2
57--70
EN
Typing microorganisms is a very important element of laboratory diagnostics. Appropriate recognition of the pathogen and determination of its sensitivity to the drugs used is necessary to start treatment. There are many types of microbial typing. The most popular division is genotypic and phenotypic typing (among which biotyping, antibiotic resistance analysis, and protein profile analysis are the most common) or phagotyping) [1, 2]. Recently, there has been a very rapid development of mass spectrometry techniques as a method for identifying microorganisms [3]. Mass spectrometry (MS) and nuclear magnetic resonance spectroscopy (NMR) are methods that allow the comparison of metabolomic profiles of microorganisms. These are also methods commonly used in metabolomics. Metabolomics is a field of science dealing with the analysis of low-mass compounds characteristic of the studied material [4]. Therefore, the use of metabolomics in microbiology allows to identify and discriminate of microorganisms [5]. Recently, the analyzes also apply to metabolites. Many studies focus on the analysis of volatile organic compounds (VOCs) that allow the analysis of samples directly from the patient without the need for isolation of a single microorganism [6, 7]. Recent studies show many possibilities for the use of NMR spectroscopy. The results of the analysis show that it is also a method that allows the identification and differentiation of strains of microorganisms. Thanks to this method it is also possible to determine the origin of the strain or to indicate its resistance to antibiotics. [10, 11]. Improvement of research algorithms used in metabolomics for biotyping microorganisms may in the future allow for the creation of a fast, accurate and cheap way to identify microorganisms. Proteomic tests using the MS method are very popular, in which protein profiles of strains are analyzed and compared. These studies are mainly conducted using MALDI-TOF MS mass spectrometry. This technique is now quite widely used in microbiological diagnostics [10]. The research confirms the high discrimination power of this method [11].
9
Content available remote Pomiary czasów relaksacji podłużnej i poprzecznej wybranych cieczy z wykorzystaniem skanera EFNMR
Trybus Mariusz
Przegląd Elektrotechniczny
|
2020
|
R. 96, nr 10
115--118
PL
Rezonans magnetyczny (NMR) jest nieinwazyjną i jedną z najbardziej dokładnych technik obrazowania we współczesnej medycynie. W niniejszej pracy przedstawiamy wyniki badań czasu relaksacji podłużnej i poprzecznej wybranych cieczy, uzyskane z wykorzystaniem stanowiska naukowo dydaktycznego EFNMR, wykorzystującego ziemskie pole magnetyczne i jego jednorodność do obrazowania, spektroskopii i pomiarów z wykorzystaniem NMR.
EN
Nucleart magnetic resonance (NMR) is one of the most non-invasive and most accurate imaging techniques in modern medicine. In this paper we present the results of measurements of longitudinal and transverse relaxation of selected liquids, obtained using the EFNMR scanner, using the Earth's magnetic field and its homogeneity for imaging, spectroscopy and NMR measurements.
10
Content available remote Growth and characterization of 4-(((4-aminophenyl)sulfonyl)oxy)-2,3-dihydroxy-4-oxobutanoic acid with Ce3+: for semiorganic nonlinear optical application
Vinoth E., Vetrivel S., Gopinath S., Aruljothi R., Suresh T., Mullai R. U.
Materials Science Poland
|
2020
|
Vol. 38, No. 4
584--593
EN
This work aims at the growth and characterization of novel semi-organometallic nonlinear optical (NLO) crystal 4-(((4- aminophenyl) sulfonyl) oxy)-2,3-dihydroxy-4-oxobutanoic acid (ASODA) with ammonium ceric (II) sulfate dehydrate (ACS). The crystal 4-(((4-aminophenyl) sulfonyl) oxy)-2,3-dihydroxy-4-oxobutanoic acid with Ce3+ (STA) was grown by slow evaporation solution growth technique using deionized water as a solvent. Crystalline system of the grown STA crystal was identified by a single crystal X-ray diffraction study and confirmed as monoclinic crystalline system with non-centrosymmetric space group P21/C. The powder X-ray diffraction study confirmed the purity and crystallinity of the crystal. The presence of functional groups and hydrogen bonds (–O–H–O–) was confirmed by FT-IR spectroscopy. UV-Vis spectra showed that the grown crystal had a low cutoff wavelength at 219 nm. The position of protons and carbons were determined by structural studies based on NMR technique. The grown crystal was thermally stable up to 130 °C and its melting point was 163 °C. The SHG studies were performed by Quanta Ray Model laser source using Kurtz powder technique. The NLO efficiency of the STA crystal was 0.5 times greater than that of standard KDP. The dielectric constant and dielectric loss of the grown crystal were studied at different temperatures. The surface morphology and the particle size of the crystal were determined by FE-SEM technique. From the mechanical studies, it was found that the grown crystal is a soft material.
11
Content available Właściwości fizykochemiczne i funkcjonalne biokompozytów polimerowych
Wiśniewska-Wrona Maria, El Fray Mirosława
Polimery
|
2019
|
T. 64, nr 1
23--33
PL
Otrzymano błony biokompozytowe wytworzone na bazie chitozanu (Chit) i alginianu sodu (Alg) z udziałem substancji leczniczych o działaniu przeciwzapalnym (siarczan cynku) i przeciwbakteryjnym (sulfanilamid). Metodami spektrofotometrii w podczerwieni (FT-IR), magnetycznego rezonansu jądrowego (NMR) oraz różnicowej kalorymetrii skaningowej (DSC) oceniono wpływ zawartości chitozanu i alginianu na budowę chemiczną i temperaturę przemian fazowych biokompozytów. Analiza termiczna wykazała, że dodatek substancji leczniczych do materiałów biokompozytowych wpływa zarówno na obniżenie ich temperatury topnienia, jak i na zmniejszenie entalpii związanej z tą przemianą.
EN
Biocomposite films based on chitosan (Chit) and sodium alginate (Alg) and containing anti-inflammatory (zinc sulfate) and antimicrobial (sulfanilamide) pharmaceutical ingredients were prepared. The effects of variable chitosan and alginate contents on the chemical structure and phase transition temperatures of biocomposites were studied using infrared spectroscopy (FT-IR), nuclear magnetic re­sonance (NMR) and differential scanning calorimetry (DSC). Thermal analysis showed that the addition of pharmaceuticals decreased the melting temperature and melting enthalpy of polymer biocomposites.
12
Content available Determining irreducible water saturation based on well log data and laboratory measurements
Lis-Śledziona Anita, Stadtmüller Marek
Nafta-Gaz
|
2019
|
R. 75, nr 5
239--246
EN
Unconventional resources, explored recently in Poland, require alternative methods of interpretation as the methods used in the conventional reservoir characterization often lead to misleading solutions that differ from the results of field tests and laboratory analyses. This paper presents novel methods of estimating irreducible water saturation in the tight gas sandstones based on the well log data and the results of laboratory analyses, including the NMR results. The first stage of the interpretation included calculating the quartz and shale volume, and calibrating the results with the laboratory measurements (XRD). Respectively, porosity and permeability were calculated and the pore-size distribution was evaluated. Based on porosimetry measurements, there were two porosities determined with pore-sizes below 1 m and above 1 m. Based on the relationships between laboratory NMR results and parameters calculated using well log data, capillary water content and mobile water saturation was estimated. The final stage of the analysis involved the calculation of irreducible water content by the following methods: evaluating the NMR data, using the Hong model lv (Hong et al., 2017), and calculating irreducible water saturation according to Zawisza’s formula, and assuming that irreducible water saturation is related to pore space with pore-diameter below m. Irreducible water saturation identified with critical water saturation is an important parameter which should be taken into account when determining the water saturation. When the Montaron model is used, the critical water saturation values, Sc, are crucial for the correctly calculating the Water Connectivity Index (WCI). The aim of this paper was to assess the suitability of using the results of NMR measurements performed in the tight gas formations in determining irreducible water saturation. The recognition of pore diameters enables to determine the pore space occupied by free hydrocarbons and hydrocarbons stored in “tight”, micro-pore space, the exploitation of which will require the fracturing process.
PL
Prowadzone obecnie w Polsce poszukiwania w skałach o charakterze niekonwencjonalnym wymagają zastosowania alternatywnych metod interpretacyjnych, gdyż metody wykorzystywane w interpretacji złóż konwencjonalnych często prowadzą do rozwiązań sprzecznych z wynikami testów złożowych i analiz laboratoryjnych. W pracy przeanalizowano zawartość wody nieredukowalnej w piaskowcach typu tight, opierając się na profilowaniach geofizyki wiertniczej oraz wynikach analiz laboratoryjnych z uwzględnieniem wyników pomiarów NMR. Pierwszy etap pracy obejmował rozpoznanie składu litologicznego i skalibrowanie objętościowej zawartości kwarcu i minerałów ilastych z wynikami badań XRD. Kolejno wyznaczono przepuszczalność i porowatość badanej formacji oraz oszacowano rozkład wielkości porów budujących przestrzeń porową. Korzystając w wyników pomiarów porozymetrycznych, obliczono także porowatość dla porów o średnicach poniżej i powyżej 1 m. Opierając się na zależnościach pomiędzy wynikami pomiarów NMR oraz parametrami oznaczonymi na podstawie danych geofizyki wiertniczej, oszacowano zawartości poszczególnych rodzajów wód: związanej kapilarnej oraz wolnej. Finalnym etapem analizy było obliczanie zawartości wody nieredukowalnej różnymi metodami: na podstawie badań NMR, korzystając ze wzoru Honga lv (Hong et al., 2017) oraz przyjmując jako zawartość wody nieredukowalnej wartości obliczone wg wzoru Zawiszy. Woda nieredukowalna, utożsamiana z krytycznym nasyceniem wodą, jest ważnym parametrem, którego wartości należy znać i uwzględniać podczas oznaczania współczynnika nasycenia wodą. W przypadku stosowania modelu Montarona w szacowaniu współczynnika nasycenia wodą wartości krytycznego nasycenia wodą Sc są kluczowe dla poprawnego wyznaczenia WCI (water connectivity index) – współczynnika ciągłości przepływu. Celem pracy była ocena przydatności i możliwości wykorzystania wyników pomiarów NMR wykonanych w formacjach typu tight w wyznaczaniu zawartości wody nieredukowalnej. Rozpoznanie wielkości średnic porów pozwala wydzielić potencjalną przestrzeń akumulacji węglowodorów wolnych w złożach konwencjonalnych oraz węglowodorów w formacjach typu tight, których eksploatacja wymagać będzie procesu szczelinowania.
13
Content available Application of surfactant-modified montmorillonite in nitrophenol removal by adsorption
Baysal Gülay
Environment Protection Engineering
|
2019
|
Vol. 45, nr 2
19--33
EN
Quaternary ammonium salts (QASs) such as 1-methyl-di-nonyl-1 phenyl ammonium iodide (QAS1) and 1-methyl-di-dodecyl-1 phenyl ammonium iodide (QAS2) were newly synthesized by complete alkylation reaction for modification of sodium montmorillonite (Mt). The sodium montmorillonite was modified via an ion-exchange reaction with QAS1 and QAS2, and two organoclays, Mt1 and Mt2, have been obtained. The synthesized quaternary ammonium salts were analyzed by nuclear magnetic resonance spectroscopy (NMR). The organoclays (Mt1 and Mt2) were characterized by a range of methods including X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR) and scanning electron microscopy (SEM). The adsorption capacities of the synthesized organo-montmorillonites for the hydrophobic organic pollutant 4-nitrophenol (4-NP) have been evaluated. The distances between the organoclay layers showed a much better opening than that reported in the literature. The results show that the adsorption capacity increased in the order Mt2 > Mt1. The adsorption capacities of Mt1 and Mt2 for 4-NP were 77% and 81%, respectively.
14
Content available Composition of leaf and flower essential oil of Myrica gale L.
Wawrzyńczak Karolina, Jakiel Alicja, Kalemba Danuta
Biotechnology and Food Science
|
2019
|
Vol. 83, nr 1
87--96
EN
Myrica gale L. leaves were collected from two plantations in Poland and flowers from one plantation. Essential oil yield and composition were assessed according to plantation site and leaf development stage. Main components of essential oils were: 1,8-cineole, α-pinene, limonene, selina-3(7)-diene, and (E)-nerolidol. It is proven that senescent leaves are valuable source of essential oil.
15
Content available Synthesis and characterization of high-molar-mass star-shaped poly(l-lactide)s
Michalski A., Łapienis G.
Polimery
|
2018
|
T. 63, nr 7-8
488--494
EN
The synthesis of high-molar-mass linear and 6-arm star-shaped poly(l-lactide)s(PLLA’s) is presented. Dipentaerythritol and benzyl alcohol were used asinitiators and Sn(Oct)2 was applied asa catalyst in the ring-opening polymerization (ROP) of l-lactide (l-LA) carried out at 130 °C. The prepared PLLA’s were characterized by SEC (size exclusion chromatography), 1H NMR (proton nuclear magnetic resonance spectroscopy), DSC (differential scanning calorimetry), and TGA (thermogravimetric analysis). The structure of the obtained star-shaped polymers was confirmed by comparison of the radii of gyration (Rg) determined by SEC for the linear and star macromolecules. The thermal properties of PLLA’s were shown for the wide range of molar masses. Additionally, it was confirmed that Irganox stabilizer has an influence on the thermal stability of PLLA’s.
PL
Przedstawiono syntezę liniowych i 6-ramiennych gwiaździstych poli(l-laktydów)(PLLA) o dużych masach molowych. Polimeryzację z otwarciem pierścienia (ROP) l-laktydu(l-LA) inicjowaną dipentaerytrytem oraz alkoholem benzylowym prowadzono w temperaturze130 °C ­wobec Sn(Oct)2 jako katalizatora. Otrzymane PLLA scharakteryzowano za pomocą SEC (chromatografia żelowa), 1HNMR (spektroskopia magnetycznego rezonansu jądrowego), DSC (różnicowa kalorymetria skaningowa) i TGA (analiza termograwimetryczna). Strukturę otrzymanych polimerów gwiaździstych potwierdzono przez porównanie wyznaczonych w SEC promieni bezwładności (Rg) dla gwiaździstych iliniowych makrocząsteczek. Właściwości termiczne PLLA przedstawiono dla szerokiego zakresu mas molowych. Dodatkowo potwierdzono, że stabilizator Irganox ma wpływ na stabilność termiczną PLLA.
16
Content available Tautomeryzm i aktywność biologiczna β-diketonów, triketonów, β-ketoestrów i β-ketoamidów : mini przegląd
Hansen P. E.
Wiadomości Chemiczne
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2017
|
[Z] 71, 7-8
427--446
EN
The review deals with β-diketones, β-ketoester, β-ketoamides, triketones, their tautomerism and biological activity. In addition, it covers briefly methods to detect tautomerism in particular NMR and deuterium isotope effects on chemical shifts, both primary and secondary. A number of typical systems are treated such as: usnic acid, tetracyclines, piroxicam, curcurmines, humulones, acyltetramic acids and quinolone 3-esters.
17
Content available Profilowanie otworowe z wykorzystaniem zjawiska magnetycznego rezonansu jądrowego i badania NMR na próbkach skalnych dla oceny skał zbiornikowych
Jarzyna J., Maziarka D., Pasek P., Klaja J., Krakowska P., Puskarczyk E.
Przegląd Geologiczny
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2017
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Vol. 65, nr 2
105--108
EN
Results of NMR well logging and laboratory experiments were analyzed. The testing material comprised NMR data from the Upper Jurassic carbonates formation from a well located in the western part of the Carpathian Foredeep. Qualitative analysis of the T1 (longitudinal) and T2 (transverse) distributions from the NMR well logging was performed to illustrate differences in the plots regarding time position and amplitude of peaks in sandstones, carbonates and claystones. Quick identification of the reservoir zones in the borehole section was highlighted. Porosity values from NMR laboratory experiments, helium pycnometer measurements and NMR well logging were compared and the differences were explained emphasizing additional information derived from discrepancies. Permeability was calculated based on the NMR laboratory experiment results comprising free water, capillary-bound water and clay-bound water. NMR permeability calculations were compared with the results of Zawisza formula calculations and results presented by Halliburton Co. The permeability results were different, but the trend of the changes was similar. The analysis shows that NMR logging is very useful in the qualitative and quantitative interpretation of reservoirs despite the difference between the point laboratory results and continuous curves of logging outcomes. The final conclusion is as follows: to complete proper interpretation of very informative NMR laboratory and well logging data the full information about calibration of measurements should be available.
18
Content available Badanie mobilności wody w jabłkach odwadnianych osmotycznie metodą magnetycznego rezonansu jądrowego (NMR)®
Samborska K., Kowalska H., Tylewicz U., Dalla Rossa M.
Postępy Techniki Przetwórstwa Spożywczego
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2017
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Nr 2
20--26
PL
Celem prac przedstawionych w artykule jest analiza wpływu odwadniania osmotycznego (OD) na wymianę masy w jabłkach. W celu określenia zmian w strukturze oraz żywotności komórek użyto jądrowego rezonansu magnetycznego (NMR) oraz mikroskopu fluorescencyjnego. Odwadnianie osmotyczne prowadzono w roztworach sacharozy oraz mieszaninach sacharozy i soków owocowych o ekstrakcie 22 i 65°Brix w temperaturze 45°C. Analiza NMR może być wykorzystywana do określenia obecności i miejsca występowania wody w komórkach tkanki poddanej odwadnianiu osmotycznemu. Informacje te mogą być przydatne w ocenie zmian destrukcji tkanki i zaburzenia jej integralności, a od strony technologicznej do kontroli wymiany masy zachodzącej podczas odwadniania osmotycznego.
EN
The aim of this work presented in the paper is to analysis of the influence of osmotic dehydration (OD) on mass transfer in apples. Fluorescence microscopy and time domain nuclear magnetic resonance (NMR) were respectively used to evaluate cell viability and microstructural changes during osmotic dehydration. The OD of apple was carried out in 22 and 65°Brix sucrose solutions or mixture of sucrose solution and fruit juices at 45°C, for a contact period from 0 to 1440 min. NMR analysis can be used to determine the presence and water state in the dehydrated cells. This information may be useful in assessing changes in tissue destruction and its integrity, and on the technological side to control the mass exchange occurring OD.
19
Content available remote Badania surowicy krwi techniką 1H NMR : podstawowe procedury pomiarowe
Ciszek M., Boguszewicz Ł., Sokół M.
Inżynier i Fizyk Medyczny
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2017
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Vol. 6, nr 2
119--123
PL
Zaburzenie homeostazy organizmu znajduje odzwierciedlenie w zmianach funkcjonalnych, morfologicznych i molekularnych, które z kolei można wykrywać w płynach ustrojowych, na przykład w surowicy krwi. Analizowaniem procesów metabolicznych, identyfikacją zmian profilu metabolicznego zajmuje się metabolomika, a jednym z jej podstawowych narzędzi badawczych jest spektroskopia magnetycznego rezonansu jądrowego wysokiej rozdzielczości HR NMR (High Resolution Nuclear Magnetic Resonance). Techniki HR NMR i metabolomiczna analiza danych coraz częściej znajdują zastosowanie w diagnostyce medycznej i monitoringu leczenia. W tej pracy przedstawiono procedury przygotowania próbek surowicy do pomiarów spektroskopowych, opisano podstawowe sekwencje impulsowe NMR użyteczne w badaniach metabolomicznych oraz wskazano najważniejsze czynniki wpływające na jakość pomiarów.
EN
Disturbances of homeostasis of the organism are reflected in functional, morphological and molecular changes. These systemic alternations can be detected in systemic body fluids, such as blood serum. Metabolomics is emerging as a powerful tool for studying metabolic processes and identifying crucial biomarkers responsible for metabolic characteristics. One of its most commonly used technology is high resolution nuclear magnetic resonance (HR NMR) spectroscopy. HR NMR techniques and metabolomics are increasingly being used in medical diagnostics and treatment monitoring. This paper presents the procedures of preparation of serum samples for spectroscopic measurements, and describes the basic NMR pulse sequences useful in such metabolomics studies; the main factors affecting the quality of the measurement were identified.
20
Content available remote Wymywalność składników z zaczynów popiołowych aktywowanych alkalicznie, wpływ rodzaju popiołu
Varga C., Alonso M. M., Puertas F.
Cement Wapno Beton
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2017
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R. 22/84, nr 2
97--112
PL
Oddziaływanie środowiska kwaśnego na zaczyny z cementu portlandzkiego było przedmiotem szeroko zakrojonych badań, w których wykazano zmiany mikrostruktury rzutujące na spadek wytrzymałości. Jednakże wpływ roztworów agresywnych na aktywowany alkalicznie zaczyn popiołowy nadal nie jest dostatecznie wyjaśniony. Prezentowana praca obejmuje wyniki ługowalności po krótkim czasie dojrzewania (3-21 dni) zaczynów popiołowych aktywowanych alkaliami, poddawanych działaniu 6M roztworu NH4NO3, a następnie ocenie właściwości mechanicznych, w zależności od składu i struktury materiałów wyjściowych. Badano dwa różne zaczyny popiołowe aktywowane alkaliami oraz zaczyn kontrolny sporządzony z cementu portlandzkiego. Stwierdzono, że agresywny 6M roztwór NH4NO3 wywierał o wiele słabszy wpływ na wytrzymałość zaczynu popiołowego aniżeli na wytrzymałość zaczynu kontrolnego. Co więcej, rodzaj i skład popiołu lotnego były czynnikami determinującymi reaktywność tego materiału, jak również jego właściwości mechaniczne i trwałość. Stężenie kationów w ekstrakcie było niewielkie i nie stwierdzono w nim glinu, który występował w głównym produkcie hydratacji – żelu N-A-S-H. Badania metodą magnetycznego rezonansu jądrowego i spektroskopii fourierowskiej w podczerwieni wykazały, że w żel ten, pod wpływem NH4NO3, wzbogaca się w krzem. Równocześnie stwierdzono powstawanie wodorotlenku glinu.
EN
Chemical attack on Portland cement paste in acid media has been widely studied and shown to induce changes in their microstructure that is causing decrease of mechanical strength. The impact of this aggressive solution on alkali-activated fly ash (AAFA) is insufficiently understood, however. This study explored leaching in early age (3-21 day) AAFA pastes in a 6M NH4N03 solution to determine the impact on mechanical behaviour and on the composition and microstructure of the starting material on the process. Two AAFA pastes of different nature and compositions were prepared, along with control OPC pastes. The studies have shown that the aggressive 6M NH4N03 solution had a much more moderate effect on AAFA than on OPC paste strength. Furthermore, the nature and chemical composition of the starting fly-ash was governing their reactivity and hence their mechanical behaviour and durability. Whilst low amounts of cations leached out of the former material, the leachate contained no aluminium, a component found in its main reaction product, N-A-S-H gel. NMR and FTIR studies showed that the post-exposure gels had higher silicon content than the pre-exposure materials. Simultaneously these methods had revealed the formation of aluminium hydroxide.
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