Preferencje help
Widoczny [Schowaj] Abstrakt
Liczba wyników

Znaleziono wyników: 14

Liczba wyników na stronie
first rewind previous Strona / 1 next fast forward last
Wyniki wyszukiwania
Wyszukiwano:
w słowach kluczowych:  spektroskopia w podczerwieni z transformacją Fouriera
help Sortuj według:

help Ogranicz wyniki do:
first rewind previous Strona / 1 next fast forward last
EN
The paper presents the results of the analysis of selected physicochemical parameters of engine oils after their use. The oils were obtained both from urban buses belonging to the fleet of a municipal transport company in Lublin, Poland but also from the city of Pardubice in the Czech Republic. Five samples of 10W40 semi-synthetic oil and four samples of 5W30 synthetic oil were tested. Kinematic viscosity at 40°C and 100°C, oxidation, nitration, sulfonation, total acid number (TAN), total base number (TBN), remaining antiwear additives, water content and glycol content, were assessed using infrared spectroscopy (FTIR). The tests were performed on the basis of the ASTM E2412-10 standard. The article also presents the exceedance of the limit values results for the selected parameters. The results of the research can be used in optimizing the engine oil change interval so that the decision to replace the oil is justified both in economic and technical terms, taking into account the need to maintain the service life of the bus.
EN
Purpose Silica/silicate scale is a significant problem, especially in oilfield production during Alkaline Surfactant Polymer (ASP) flooding, where chemical inhibitors are the preferred method to prevent them. In this study, the effect of inhibitor vinyl sulfonated copolymer (VS-Co) on silica/silicate scale formation was analysed using X-Ray Diffraction (XRD) and Fourier-transform infrared spectroscopy (FTIR). Design/methodology/approach The functional group type of VS-Co are sulfonate ions, SO3-, and these interact in the scaling process. Bulk-inhibited scaling brine tests were conducted at 60°C and pH 8.5. During these tests, the silicon brine (with VS-Co) representing the inhibited ASP leachate was mixed with a magnesium brine representing the connate water to replicate reservoir conditions during ASP flooding. The samples tested in this study were non-inhibited Si/Mg mixed brine of 60 ppm Mg2+ and 940 ppm Si4+ (60Mg:940Si) as a blank, and inhibited 60Mg:940Si mixture with various VS-Co concentrations of 20 ppm, 50 ppm, and 100 ppm. The inhibition efficiency of the VS-Co was determined, followed by the characterisation study of the silica/silicate scale deposited from both test conditions. Findings The IR spectra of all 60Mg:940Si samples show a similar peak at 1050 cm-1 to 1080 cm-1, attributed to a Si-O covalent bond and a band at 790 cm-1 to 800 cm-1 showing the presence of Si-O-Si stretching. XRD patterns produced a broad scattering peak for all samples at 2θ of 24° showing that the samples are amorphous silica. For tests of high Mg2+ in the brine mix, 900Mg:940Si, a mix of crystalline silica and crystalline magnesium silicate was produced. Based on these results, it can be concluded that the scale formed even with 100 ppm of VS-Co present. Further studies are required to address how to mitigate scale formation effectively in the future. Research limitations/implications Based on the research conducted, we can conclude that the VS-Co alone could not significantly inhibit the formation of silica/silicate scale even at the highest concentration (100 ppm) of VS-Co. However, having VS-Co present caused an alteration in IR spectra frequency which requires further investigation to assess how best to develop the inhibiting properties of the VS-Co product. The application of nanoparticles and their successful stories spark the interest of authors in searching for an efficient method of managing the silica/silicate scale where the modification of potential scale inhibitor (SI) with nanoparticles may be able to improve the inhibition efficiency towards the silicate/silicate scale. Practical implications The presence of VS-Co in the scaling brine only slightly inhibits the Mg2+ ion (initially comes from connate water) from reacting. It is worth further investigation on how this VS-Co can make it happen. Hence, the functional groups responsible for this may be altered by adding other functional groups to provide a synergistic effect in preventing this silica/silicate scale; or by modifying the VS-Co with nanoparticles to improve their adsorption/desorption capacity. Originality/value The newly developed technique in analysing the inhibition mechanism of a chemical inhibitor using various spectroscopic analysis is promising where an alteration in the spectra may provide proof of the chemical’s inhibition efficiency.
EN
The present study reports an easy eco-friendly, cost efficient, and rapid method for the synthesis of silver nanoparticles (Ag NPs) using palm sprouts as reducing cum capping agent. Green synthesis of silver nanoparticles was successfully performed using palm sprouts plant extract via a simple and cheaper eco-friendly method. Palm sprouts extract reduces silver nitrate to silver nanoparticles. The resulting materials were analyzed by Fourier-transform infrared spectroscopy (FTIR), Scanning Electron Microscopy (SEM), and X-ray Diffraction (XRD) analysis. FT-IR spectrum confirms the presence of various functional groups in the active biomolecules, it acts as a capping agent for the nanoparticles. The morphology of this sample was analyzed through SEM and the presence of silver was confirmed accordingly. The green synthesized Ag NPs exhibited an excellent antibacterial activity against E. coli and P. aeruginosa and B. subtilis and S. aureus besides imparting efficient antimicrobial activity against pathogenic bacteria as well.
EN
This paper presents a structural analysis of various methods to produce bacterial cellulose (BC) from Nata de Coco (Acetobacter xylinum). BC sheet, BC chem and BC mech powders were successfully prepared using oven drying, chemical and mechanical treatment. The X-ray diffraction (XRD), Fourier transform infrared (FTIR) spectroscopy, and field emission scanning electron microscopy (FESEM) were used to analyze the structure of prepared BC. The structure of bacterial cellulose was compared with the structure of commercial microcrystalline cellulose (MCC) and cotton fabric. The XRD results showed that the BC sheet sample had the highest degree of crystallinity (81.76%) compared to cotton cellulose (75.73%). The crystallite size of cotton was larger than the BC sheet, with the value of 6.83 ηm and 4.55 ηm, respectively. The peaks in the FTIR spectra of all BC were comparable to the commercial MCC and cotton fabrics. FESEM images showed that the prepared BC sheet, BC mech, and BC chem had an almost similar structure like commercial MCC and cotton fabric. It was concluded that simple preparation of BC could be implemented and used for further BC preparation as reinforcement in polymer composites, especially in food packaging.
PL
Niniejszy artykuł zawiera analizę struktury celulozy bakteryjnej (BC) wytworzonej z Nata de Coco (Acetobacter xylinum) różnymi metodami. Folia BC i proszki BC chem oraz BC mech zo -stały wytworzone poprzez suszenie w piecu, obróbkę chemiczną i mechaniczną. Do oceny struktury celulozy bakteryjnej stosowano dyfrakcję rentgenowską (XRD), spektroskopię Fouriera w podczerwieni (FTIR) i skaningową mikroskopię elektronową z emisją polową (FESEM). Strukturę celulozy bakteryjnej porównano ze strukturą handlowej celulozy mikrokrystalicznej (MCC) i tkaniny bawełnianej. Wyniki XRD wykazały, że najwyższy stopień krystaliczności miała próbka arkusza BC (81,76%) w porównaniu z celulozą bawełnianą (75,73%). Wielkość krystalitów bawełny była większa niż folii BC i wynosiła, odpowiednio, 6,83 ηm oraz 4,55 ηm. Piki widm FTIR wszystkich otrzymanych form celulozy bakteryjnej były porównywalne z komercyjnymi tkaninami bawełnianymi i z celulozy mikrokrystalicznej. Zdjęcia FESEM folii BC oraz proszków BC mech i BC chem również były podobne do komercyjnej MCC i tkaniny bawełnianej. Stwierdzono, że z wykorzystaniem prostych technik można otrzymać BC, która może być stosowana jako wzmocnienie w kompozytach polimerowych, w szczególności w opakowaniach do żywności.
EN
Purpose: There are several advantages of using a biological technique to produce nanoparticles versus a chemical method. The primary goal of this work is to characterize and biologically synthesize titanium dioxide (TiO2) nanoparticles from Cynodon dactylon. The characterization has experimented with UV-Vis Spectroscopy, EDX analysis, SEM, XRD, and FTIR. Design/methodology/approach: The suggested study uses a simple biological technique to accomplish the systematic biological synthesis of TiO2 nanoparticles utilizing Cynodon dactylon plant extract and titanium tetra isopropoxide as a precursor. UV-Vis spectroscopy, Scanning Electron Microscopy (SEM), Fourier Transform Infrared Spectroscopy (FTIR), and X-Ray Diffraction (XRD) are used to confirm the fabrication of the TiO2 nanoparticles. The plant extract as well as titanium-based nanoparticles of the herb, Cynodon dactylon will be tested for its antibacterial activity against human pathogens. This eco-friendly technique for nanoparticle synthesis is straightforward and adaptable to major commercial manufacturing and technological applications. Findings: Cynodon dactylon biosynthesis of TiO2 nanoparticles is efficient, nutrition dependent, does not employ hazardous compounds, and happens at neutral pH levels. The antibacterial study results show that TiO2 nanoparticles synthesized using Cynodon dactylon have good antibacterial properties. TiO2 nanoparticle method of action against bacteria is unknown. This is an alternative process for synthesising TiO2 nanoparticles, apart from other chemical protocols, since this is quick and non-toxic. The antimicrobial property of biologically synthesized TiO2 nanoparticles against Escherichia coli, Staphylococcus aureus, and Acinetobacter baumannii was tested at four different doses of 15 μl/mg, 25 μl/mg, 50 μl/mg, and 75 μl/mg. The present results revealed the 75 μl/mg concentration got the highest zone of inhibition (15, 13, 15 mm) for Acinetobacter baumannii, Staphylococcus aureus, and Escherichia coli. Research limitations/implications: Many nanoparticles smaller than 100 nm are firmly agglomerated with each other in the study. TiO2 nanoparticles absorb in the UV region of 200 to 400 nm. XRD measurements confirmed the presence of TiO2 nanoparticles in the biologically produced sample. In our work, EDX was used to confirm the existence of Ti after its synthesis by Cynodon dactylon. Practical implications: The biosynthesized TiO2 nanoparticles utilizing Cynodon dactylon plant extracts exhibit a good potent antibacterial activity. The proposed results showed that the TiO2 nanoparticles are well suited for biomedical applications. Originality/value: The suggested research identifies several eco-friendly, biological, and cost-effective procedures for manufacturing nano-coated herbal products. The agar well diffusion technique was used to assess antibacterial activities toward test pathogens such as Acinetobacter baumannii, Staphylococcus aureus, and Escherichia coli.
EN
Compostable biodegradable plastics are an ecological alternative to traditional products based on petroleum derivatives, whose post-use waste may pollute the natural environment. Modern polymer materials show the functional properties of plastics obtained by conventional methods, but they also may be degraded as a result of biochemical transformations in composting. This allows such materials to be included in the scheme of the currently implemented circular economy, which does not generate post-consumer waste. This paper presents methods for the assessment of the biodegradation process of selected agricultural nonwovens produced from commercial PLA 6252D polylactide, supplied by Nature Works® LLC, USA. The agricultural nonwovens tested, obtained by the spun-bond technique, were characterised by different degrees of crystallinity in the range from 11.1% to 31.4%. Biodegradation tests were carried out as simulated aerobic composting while maintaining constant environmental conditions in accordance with test procedures based on PN-EN/ISO standards using the method of sample mass loss determination. Gel chromatography (GPC/SEC) and FTIR spectroscopy were also applied to assess the degree of biodegradation. The aim of this study was to evaluate the effect of the crystallinity of nonwoven made of PLA 6252 D on its degradation in a compost environment.
PL
Kompostowalne tworzywa biodegradowalne są ekologiczną alternatywą dla tradycyjnych produktów opartych na pochodnych ropy naftowej, zalegających i zanieczyszczających środowisko naturalne w formie odpadów poużytkowych. Nowoczesne materiały polimerowe wykazują właściwości użytkowe tworzyw sztucznych otrzymywanych metodami konwencjonalnymi a ponadto ulegają utylizacji na drodze przemian biochemicznych w wyniku kompostowania. Pozwala to na wpisanie się takich materiałów w schemat obecnie pożądanej gospodarki cyrkularnej, która nie generuje odpadów poużytkowych. W niniejszej pracy przedstawiono metody badań biorozkładu wybranych agrowłóknin wytworzonych z komercyjnego polilaktydu PLA 6252D firmy Nature Works® LLC, USA. Badane agrowłókniny otrzymane techniką spun-bonded charakteryzowały się różnymi stopniami krystaliczności w zakresie od 11.1% do 31.4%. Badania biodegradacyjnie prowadzono w procesie symulowanego kompostowania aerobowego z zachowaniem stałych warunków środowiskowych zgodnie z procedurami badawczymi na podstawie norm PN-EN/ISO z wykorzystaniem metody wyznaczania ubytku masy. Do oceny stopnia biodegradacji zastosowano również technikę chromatografii żelowej (GPC/SEC) oraz spektrofotometrię FTIR. Celem pracy było określenie wpływu krystaliczności włóknin wytworzonych z PLA 6252 D na rozkład w środowisku kompostowym.
EN
The aim of this research was to identify optimum values of the colorfastness properties of sustainable dyes on cotton fabrics. Sustainable dyes are ecofriendly, biodegradable, economical and easily attainable from natural sources. The findings of this research established that good colourfastness properties of cellulosic fibres could be obtained using sustainable natural dyes. Experiments were carried out on 100% cotton voile fabrics of plain weave using four types of natural dyes: strawberry dye, beetroot dye, rose dye and China rose dye. Strawberry dye reacted with the cellulose of the cotton in an alkaline condition to form a stable covalent bond amid the dye and cellulose and showed outstanding colour fastness properties. The required experiments were conducted using the standard specified by ASTM and AATCC as stated in this paper. The colour strength properties, colour intensity properties, colour absorbency properties and colorfastness properties were investigated using a reflectance spectrophotometer and “Agilent Cary 630 FTIR Instrument” as stated in this paper. A sample dyeing machine – “Pad Dye Pad Steam” was used in this research to dye the cotton fabrics with sustainable natural dyes. The colorfastness properties were investigated using grey scale test results, and the colour strength and absorbency properties were tested using the spectrophotometer and FTIR instruments. The peak values of the FTIR instrument guaranteed the existence of the colourant or chromophore present in the dyestuffs, and exposed the best colourfastness properties. The findings of this research could be beneficial to personnel involved in textile industries who are in charge of dyeing cotton fabrics with natural dyes as well as controlling their colourfastness properties and colour intensity properties.
PL
Celem badań było określenie optymalnych wartości właściwości trwałości koloru barwników naturalnych na tkaninach bawełnianych. Naturalne barwniki są przyjazne dla środowiska, biodegradowalne, ekonomiczne i łatwo dostępne z naturalnych źródeł. Wyniki tych badań wykazały, że dobre właściwości trwałości koloru włókien celulozowych można uzyskać przy użyciu trwałych naturalnych barwników. Eksperymenty przeprowadzono na tkaninach woalowych w 100% bawełnianych o splocie płóciennym przy użyciu czterech rodzajów barwników naturalnych: barwnika truskawkowego, buraczkowego, różowego i chińskiego różowego. Barwnik truskawkowy przereagował z celulozą bawełny w środowisku zasadowym, tworząc stabilne wiązanie kowalencyjne między barwnikiem i celulozą i wykazał wyjątkową trwałość koloru. Wymagane eksperymenty przeprowadzono przy użyciu standardu określonego przez ASTM i AATCC. Właściwości trwałości koloru zbadano za pomocą wyników testu w skali szarości, a siłę koloru i właściwości absorpcyjne zbadano za pomocą spektrofotometrii w podczerwieni (FTIR).
EN
Biochar has been extensively studied in the aspect of amendment of compacted sandy/clayed soils, whereas its application as amendment in expansive soil is rare. Hydraulic and mechanical properties of biochar-amended expansive soil especially impacts of drying–wetting cycles have been rarely investigated. Aiming at construction of sponge city, straw biochar-amended expansive soil and the control soil (i.e., without biochar) are subjected to drying–wetting cycles in this study. During drying–wetting cycles, energy-dispersive spectrometer and Fourier transform infrared (FTIR) spectroscopy analyses were conducted to investigate microchemical composition including. Pore size distribution and microstructure were measured using nitrogen gas-adsorption technique and scanning electron microscope, respectively. Further, changes in soil water retention curve, void ratio, crack intensity factor (CIF, i.e., ratio of cracked section area to the total soil area) and shear strength were also determined. It is found that there is no diference in water retention capacity between various soils for near-saturated samples. Under high suction, however, more water could be retained within mesopores of biochar-amended soil. FTIR analysis indicates that biochar-amended expansive soil shows stronger chemical bonding, irrespective of them being subjected to drying–wetting cycles. The weak alkalinity of straw biochar results from its main chemical composition (i.e., calcium carbonate). It is noteworthy that straw biochar improves soil water retention capacity, which further restrains desiccation cracks. Cohesion of biochar–soil composite is also improved due to chemical bonding. Aiming at green roofs, straw biochar could be promising option for expansive soil amendment technically and economically.
9
PL
W artykule przedstawiono nową metodę pobierania materiału do przygotowania próbek w analizie FTIR, którą można wykorzystać do określenia postępu karbonatyzacji betonu. Uzyskane wyniki porównano ze stosowaną do tej pory metodą wiercenia próbki. Przeprowadzono analizę dwóch mieszanek betonu samozagęszczalnego. Badane próbki miały postać typowych sześciennych kostek oraz gruzu betonowego. Próbki były przechowywane przez 56, 112 i 168 dni w komorze karbonatyzacyjnej. Jednocześnie wykonano analizę termiczną TG/DTA. Uzyskane wyniki potwierdziły zalety zaproponowanej metody.
EN
The paper presents a new sampling method for the FTIR analysis, which might be used for the determination of the concrete carbonation progress.The obtained results were compared with the existing drillng method. In the research two self-compacting concretes were used. The tested samples were cubicones and concrete crushed rubble. Samples were kept for 56, 112 and 168 days in the carbonation chamber. To verify the obtained results, thermal analysis – TG/DTA was carried out for samples stored for 168 days in CO2 environment. The achieved results of thermal analysis, confirmed advantages of the proposed sampling method.
PL
W niniejszym artykule przedstawiono wyniki badań dotyczących wpływu tlenku grafenu (GO) i zredukowanego tlenku grafenu (rGO) na wybrane właściwości strukturalne wodorozcieńczalnej żywicy akrylowej. Ocenie poddano również właściwości aplikacyjne lakieru tj. grubość i połysk. Analiza strukturalna powłok otrzymanych z wodorozcieńczalnej żywicy akrylowej z dodatkiem GO lub rGO wykazała równomierny rozkład pochodnych grafenu w warstwie wierzchniej oraz brak spękania i łuszczenia. Badania za pomocą spektroskopii w podczerwieni z transformacją Fouriera (FTIR) nie ujawniły pików powstałych w wyniku reakcji chemicznej i procesu sieciowania spoiwa lakieru z GO lub rGO.
EN
This paper presents the results of research concerning the influence of graphene oxide (GO) and reduced graphene oxide (rGO) on selected structural properties of water-borne acrylic resin. The application properties of the lacquer, i.e. the thickness and the specular gloss were also evaluated. Structural analysis of coatings obtained from water-borne acrylic resin with the addition of GO or rGO showed an even distribution of graphene derivatives in a top layer and no cracking or flaking. The FTIR analysis did not reveal any signals resulting from the chemical reaction and the crosslinking process of the lacquer binder with GO or with rGO.
PL
Spektroskopia podczerwieni z transformacją Fouriera oferuje szybkie i tanie rozwiązanie w niedestrukcyjnej analizie różnego rodzaju produktów spożywczych. Próbki mogą być analizowane bezpośrednio, co wpływa na ograniczenie kosztów poprzez zaoszczędzenie czasu i odczynników. Nawet substancje niejednorodne mogą być analizowane bez specjalnego przygotowania.
EN
Fourier Transform Near lnfrared (FT-NIR) spectroscopy offers a fast and cost-effective solution for the non-destructive analysis of various food and feed samples for quality control applications. The samples can be analyzed directly, saving costs by reducing time and reagent use. Even inhomogeneous materials can be analyzed without sample preparation.
PL
Przedstawiono wyniki badań nad mody fika ej ą po wierzchni węgli aktywnych serii CWZ wodnym 25 % roztworem amoniaku w temperaturze pokojowej . Modyfikacja wodą amoniakalna prowadzi do utworzenia na powierzchni wQgli grup funkcyjnych zawierających azot, co potwierdzono wynikami analiz powierzchni badanych węgli aktywnych metodą spektroskopii w podczerwieni z transformacjąFouriera (FTIR) oraz spektroskopii fotoelektronów rentgenowskich (XPS). Dodatkowym potwierdzeniem zajścia modyfikacji oraz źródłem informacj i na temat trwałości utworzonych w strukturze węgli powierzchniowych grup funkcyjnych zawierających azot były wyniki analiz TPD-FTIR. Jak stwierdzono, ogrzewanie próbek węgli modyfikowanych w zakresie temperatur 300-550°C prowadzi do wydzielania się amoniaku z wprowadzonych grup powierzchniowych. Wykonane pomiary adsorpcj i z fazy wodnej na uzyskanych węglach aktywnych, potwierdziły podwyższenie zdolności adsorpcyjnych węgli wobec fenolu jako reprezentatywnego zanieczyszczenia wód o charakterze kwaśnym.
EN
Results of modification of CWZ series activated carbons with aqueous ammonia at room temperature is described. As confirmed with both Fourier-transform infrared spectroscopy (FTIR) and X-ray pholoelectron spec-troscopy (XPS), mentioned modification results in formation of nitrogen-containing surface groups on the surface of researched activated carbons. Performed additionally temperature-programmed desorption (TPD) coupled with FTIR proved incorporation of nitrogen to the carbons structure and gave an information about thermal stability of the surface groups. As found, heating of the modified carbons at temperature ranging from 300 to 550°C causes destructive decomposition of the N-containing groups with evolution of ammonia. The modified activated carbons showed increased adsorption of phenol from water.
PL
W artykule przedstawiono wyniki badań utleniania folii z polietylenu małej gęstości (PELD), zarówno w całej objętości materiału jak i w warstwie wierzchniej, zachodzącego pod wpływem modyfikowania promieniami gamma. Do tych badań zastosowano spektroskopię w podczerwieni z transformacją Fouriera (FTIR) oraz spektroskopię fotoelektronową (XPS). Stwierdzono, że wraz ze wzrostem dawki promieniowania następuje wzrost utleniania folii PELD zarówno w jej wnętrzu jak i w warstwie wierzchniej. Produktami tego procesu są głównie grupy ketonowe, aldehydowe, kwasowe i estrowe. Zawartość tlenu w warstwie wierzchniej badanej folii wzrasta w przybliżeniu liniowo wraz ze wzrostem dawki promieniowania. Jest ona ponad dwudziestotrzykrotnie większa w warstwie wierzchniej folii modyfikowanej dawką 150 kGy niż w warstwie wierzchniej folii niemodyfikowanej.
EN
The results of low-density polyethylene (PELD) film oxidation occuring in the polymer bulk and surface layer during gamma irradiation were presented. Fourier transform infrared spectroscopy (FTIR) and X-ray photoelectron spectroscopy (XPS) measurements were performed. It has been established that the bulk oxidation and surface layer oxidation of PELD film increases with the increase of radiation dose and the oxygen occurs mainly in ketone, aldehyde, carboxylic acid and ester groups. It has been shown that oxidation degree of surface layer of PELD film increases almost linearly with the increase of radiation dose and is over twenty three times higher for modified 150 kGy dose PELD film as compared to the nonmodified PELD film.
first rewind previous Strona / 1 next fast forward last
JavaScript jest wyłączony w Twojej przeglądarce internetowej. Włącz go, a następnie odśwież stronę, aby móc w pełni z niej korzystać.