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In the past, polyacrylamide hydrogel was a popular choice for breast augmentation filler, and many women underwent mammoplasty with this gel. However, due to frequent complications, the use of polyacrylamide hydrogel in mammoplasty has been banned. Despite this ban, patients experiencing complications still seek medical treatment. The aim of this study was to investigate the fate of the polymer over a defined implantation period. Biopsies of breast implants were obtained from patients with 23 and 27 years of post-mammoplasty. These biopsies were meticulously purified from biological impurities and subjected to analysis using IR spectrometry, liquid chromatography—mass spectrometry, gas chromatography, and differential scanning calorimetry. The findings revealed the presence of polyacrylamide hydrogel residues, along with degradation products, within the infected material. Notably, the low-molecular-weight degradation products revealed via gas chromatography are aggressive and toxic substances capable of inducing chronic inflammation. This study sheds light on the long-term consequences of polyacrylamide hydrogel implantation, highlighting the persistence of harmful degradation products and their role in exacerbating patient complications. [ABSTRACT FROM AUTHOR]

Background. The increasing pollution of natural waters by heavy metals has become a major problem in recent years, so their determination requires separation and pre-concentration techniques. Purpose. Development of a hybrid, sensitive sorption-spectrophotometric method for determining the Zn(II) ion using a polyethylene polyamine polyacrylonitrile (PPF-1) matrix immobilized in alizarin red C. Methodology. Research was carried out using a spectrophotometer, diffuse reflectance spectroscopy, IR spectroscopy and methods of mathematical statistics. Originality. For the first time, alizarin red C (AKS) was immobilized on a modified PPF-1 and a new matrix was used for the effective determination of Zn(II) Findings. The sensitivity of Zn(II) determination by selective immobilized ACS was maximum at 522 nm. The optimal pH for determining Zn(II) is 5.0 at room temperature. The linear range was found to be 6.5-40 mg/L, the detection limit was 0.6 mg/L, and the adsorption percentage was about 97%. [ABSTRACT FROM AUTHOR]

The work is concerned with the study of a relatively new prospective composite material based on basalt fibers. In this work, an attempt has been made to investigate in more depth the structural changes that occur during irradiation of basalt composite samples by gamma ray streams and which affect the mechanical properties. The changes that have occurred during radiation modification have been evaluated by mechanical tests and infra-red spectrum investigations. The impact of the material structure on the elastic properties of the irradiated basalt composite is reasonably assumed. It is discovered that the modification of the material by gamma irradiation leads to an increase in the elastic properties of the basalt composite. At the same time the value of fracture strain decreases. Analysis of the IR spectrum in the high-frequency region showed that the radiation exposure results in continuing polymerization reactions and intermolecular cross-linking. However, when the radiation dose reaches 15 Mrad, there is a reduction in the number of bonds in the low-frequency region of the spectrum, which, according to the authors, corresponds to a breakdown of the aluminum-silicon-oxygen and organo-silicate frameworks. [ABSTRACT FROM AUTHOR]

The interaction of host molecules with water molecules is of primary importance in astrophysical and atmospheric studies. Water-binding interactions continue to attract a broad interest in various fields, especially those related to the formation of assembly structures. Using the physical vapor deposition (PVD) method and a two-beam interferometer with a wavelength of 406 nm, the refractive indices of thin films of a water and nitrogen (argon) mixture were calculated in the range from 15 to 35 K. The results of temperature transformations of the obtained films from a two-beam interferometer, and thermal desorption characteristics from the temperature of condensation to the temperature of evaporation of water (15–180 K), are presented. The relationship between the signal of the interferometer, the refractive index, and the film thickness during glass transition is demonstrated. [ABSTRACT FROM AUTHOR]

The effect of N-layer-by-layer promotion (N = 0, 1, 5, 10 layers) of Co/MgAl2O4 catalysts (MgAl2O4 is aluminum-magnesium spinel with Ssp = 23 m2/g) with glucose on the textural and physicochemical properties of the catalyst was studied. For Co-supported catalysts, the dispersity of cobalt increased significantly after promotion of the MgAl2O4 support with glucose (N > 1). For cobalt catalysts prepared by impregnation of the support with both cobalt nitrate and glucose, the dispersity of cobalt did not change. [ABSTRACT FROM AUTHOR]

The liquid and solid products obtained in the high-temperature extraction of Kaa-Khem coal in supercritical benzene are studied by chemical and physicochemical methods. Possible applications are proposed for the soluble high-molecular components and the solid carbon and ash residues. [ABSTRACT FROM AUTHOR]

The article provides the results of the analysis of methods and instrument equipment for the assessment of quality parameters of retted flax straw and flax fiber. The traditional methods and equipment are presented. The devices developed for flax fiber quality testing used in the Russian Federation, the Republic of Belarus and Ukraine are described. Methods, equipment and modern technologies used to determine the quality of flax fiber in European countries, Canada and the United States are provided. The role of modern developments to improve the efficiency of flax production is noted. Promising methods and devices for determining the main quality indicators are identified. The use of the method of automated forecasting of technological value of fiber flax stalks makes it possible to conduct a comprehensive quality assessment based on morphological and anatomical analysis. Modern capabilities of electronic scanning microscopy provide the control of the chemical composition and structural elements of flax stems at various stages of growth and development, as well as during maceration. The use of infrared spectrometry provides high accuracy in determining humidity, strength, fiber content, and long fiber yield.However, along with high-precision equipment, there is the need for equipment and devices that allow determining the main technological indicators in the field with minimal labor, time and money costs. Research in this direction was previously carried out at the All-Russian Scientific Research Institute of Bast Crops Processing and in Kostroma State Technological University. However, the developments of the scientists were not tested in the production process and were not mass-produced. High speed and objective measurement methods will provide the accurate indicators during the process of maceration and primary processing of retted straw that will increase the technological value and competitiveness of flax fiber.

Introduction. The quality control of a medicinal product needs to be systematically improved in connection with a continuous increase in the requirements for the quality of medicines. When assessing the quality of substances and drugs, the most important indicators are authenticity, the content of the main substance and impurities. This makes it relevant to introduce modern physical and chemical methods of analysis into industrial practice in determining parameters such as authenticity, the content of the main substance and impurities. The choice and applicability of a particular method is possible only when conducting comparative studies on the application of a particular method to solve this problem. The method should preferably be recommended by the Pharmacopoeia, give unambiguous results, and the analysis should not be expensive and affordable. The methods chosen for comparative analysis are well known, but it should be noted that in recent years, instrument-making companies have significantly improved their instrument base and expanded their capabilities. Therefore, one of the objectives of this article is to demonstrate the capabilities of the selected methods for solving the problems of drug quality control using dalargin as an example.Aim. To develop methods for determining the authenticity of the active substance in a substance - Dalargin powder using NMR spectroscopy, IR spectrometry, and Mass spectroscopy. Conduct a comparative analysis of the applicability of the selected methods to solve the problem.Materials and methods. To determine the authenticity of the substance - the powder «Dalargin» used the methods of mass spectrometry, 13C NMR and 1H NMR spectrometry and IR spectrometry.Results and discussions. Methods have been developed for determining the authenticity of the test substance by NMR, IR, and mass spectrometry. A comparative study of the possibilities of the selected methods in solving the problem. Conclusions were drawn about the applicability of the NMR method not only in determining the authenticity of dalargin, but also in solving the problem of determining the content of the main substance and impurities.Conclusion. Authenticity methods have been developed in the substance - Dalargin powder by Mass, IR, and NMR spectrometry. It has been established that 1H NMR spectrometry is a more informative method for authenticating.

The quaternary cyanamide Li2MgSn2(NCN)6 was prepared by a solid‐state metathesis reaction between Li2NCN, MgF2, and SnF4. Its trigonal structure was determined from powder X‐ray diffraction data to be isotypic to that of Li2MnSn2(NCN)6 with P3‾1m symmetry. The new phase is well thought of as being derived from a [NiAs]‐type MNCN structure with Sn2(NCN)32+ corundum‐like layers alternating with Li2Zr(NCN)3‐like Li2Mg(NCN)32− layers. Structural anomalies in the shape of the cyanamide units are addressed via PXRD, IR spectroscopy as well as density‐functional theory, all of them suggesting the presence of N≡C−N2− cyanamide units. [ABSTRACT FROM AUTHOR]

The quaternary cyanamide Li2MgSn2(NCN)6 was prepared by a solid‐state metathesis reaction between Li2NCN, MgF2, and SnF4. Its trigonal structure was determined from powder X‐ray diffraction data to be isotypic to that of Li2MnSn2(NCN)6 with P3‾1m symmetry. The new phase is well thought of as being derived from a [NiAs]‐type MNCN structure with Sn2(NCN)32+ corundum‐like layers alternating with Li2Zr(NCN)3‐like Li2Mg(NCN)32− layers. Structural anomalies in the shape of the cyanamide units are addressed via PXRD, IR spectroscopy as well as density‐functional theory, all of them suggesting the presence of N≡C−N2− cyanamide units. [ABSTRACT FROM AUTHOR]

The oil and gas potential of the southeast of Western Siberia dictates increased attention to plant phytoleimmas from the Naunak and Tyumen formations. The morphological features of fossil plants are often insufficient for distinguishing horizons or formations within sedimentary strata. Infrared (IR) spectroscopy allows revealing new diagnostic features in the structures of phytofossils. It has been established that the structure of the Czekanowskiales phytoleimmas from the Tyumen Formation, in contrast to those from the Naunak Formation, have a greater number of nitrogen bonds of amino acids and an increased number of oxygen and hydrogen bonds with carbon in the form of carboxyl (1690 cm–1), carbonic (1600 cm–1), and methylene (2920 cm–1) compounds. According to the spectral characteristics of the diffuse reflection of bands at 7500, 4000, 3040, 2920, 2860, 2000, 1690, 1600, 1260, 1090 and 1030 cm–1, indicating to some extent the chemical structure of phytofossils (ancient plants) and herbarium (modern plants), carbon and ether bonds in framework compounds (1600, 1260 cm–1) and bonds of inorganic compounds (1090 cm–1), which are an integral part of organic matter, were revealed in the phytoleimmas of horsetail plants. Consequently, the bonds of the structural elements forming the frame tissues of the plant, while decreasing in quantity during fossilization, retain the appearance of the original tissue. [ABSTRACT FROM AUTHOR]

The paper analyzes the structure of Upper Devonian reef strata within Moroshkinsky, Ust-Tsilemsky and Severo-Tebuksky reference sites located in the territory of the Komi Republic and Nenets Autonomous Okrug. Based on the re-interpretation of the materials of geophysical well logging involving lithologic description of core and results of its laboratory studies, a detailed analysis of the structure of Domanic-Famenian part of the profile has been made, and a correlation pattern for deep well profiles has been drawn. As a result of well log correlation, some of the stratigraphic boundaries have been updated, the scope of lithologic and stratigraphic subdivisions has been determined, reference bands with good visibility on geophysical diagrams and easily traceable carbonate formations known to geologists as F1, F2, F3, F4, F5, as well as inter-formation bands, have been specified. The paper contains the results of a geochemical study of the Upper Devonian reef deposits of the wells drilled in the territory of Moroshkinsky, Ust-Tsilemsky and Severo-Tebuksky sites. It presents content distribution of organic carbon, chloroform and alcohol-benzol extracted bitumoids in the rocks of certain well horizons, and describes oil generation potential of the rocks on the basis of pyrolytic data. Based on the comprehensive analysis of the results of laboratory core analysis and materials of production log tests, reservoir quality discrimination has been performed, an evaluation of their quantitative parameters and fluid content has been made. Porosity factor has been selected as the criterion for evaluation of reservoir properties of the rocks. Determination of porosity by neutron gamma-ray logging has been performed following the method of two guide formations using the dependencies developed by JSC KamNIIKIGS. For evaluation of quantitative parameters of carbonate reservoirs, the results of standard core analysis were used: effective porosity, absolute permeability to gas, and volumetric density. The results of the research can be used during prospecting and exploration in the territory of the three reference sites of interest.

In this study, the author set out to determine the chemical composition and possible use of a substance, which remnants were found on a tile fragment made of soft brown shist. This item was discovered in the occupa-tion layer of a Neolithic settlement belonging to the Boborykino culture (Mergen 3), located on the terrace of Lake Mergen in the forest-steppe of the Ishim area (south of Western Siberia). By analogy with the complexes of the Boborykino culture in the Tobol area — Yurtobor 3 (7701 ± 120 BP (UPI 559)) and Tashkovo 1 (7440 ± 60 BP (LE 1534)) — which age was determined using carbon-14 dating, the Mergen 3 settlement can be attributed to the second half of the 7th millennium Cal. BC. The fragment measuring 3.0 × 2.1 × 0.55 cm has a spherical indenta-tion in the centre measuring 2.0×2.0×0.2 cm with a volume of 0.118 cm3 (0.118 ml). The whole item probably had a square shape with rounded and slightly raised edges. A visual analysis of the spot was carried out using an MBS-10 binocular microscope at a magnification of 16×. The analysis revealed a brown substance on the edges of the indentation, which looked like a dark porous carbon-like spot in the centre. These remnants were studied using a Bruker ALPHA FT-IR spectrometer with an Eco-ATR module — a single reflection ATR sampling module equipped with a zinc selenide crystal (ZnSe) that allows you to analyse liquid, solid and powder samples without preliminary sample preparation. The measurements were performed in the wavenumber range of 300–4000 cm-1 at a resolution of 4 cm-1. Some of the most significant absorption bands (709; 975; 1,024; 1,027 cm-1) were ob-served, which characterise vibrations bending and stretching the bonds in the skeleton of an organic molecule containing single С–С and С–О bonds. The obtained spectra are most consistent with the IR absorption spectra of resin acids, in particular, dehydroabietic acid that is present in resin obtained from coniferous trees. Consider-ing the small volume of the above-mentioned substance and the limited of its burning, the author excludes the use of this tile as a lamp, the use of the substance for the preparation of glue that held together the parts of complex tools, as well as the use of the substance for healing wounds and for cosmetic purposes, which involved addi-tional ingredients. Signs of burning indicate the use of the artefact for rituals, in particular for obtaining finely dis-persed soot employed when applying tattoos. The conducted experiment showed that the soot from a burnt drop of fresh resin covered 4 cm2 of the wrist area. Soot formed at the very beginning of the combustion process (probably combustion of volatile components), then the substance was oxidised without noticeable emissions. The remnants of the porous substance on the tile confirm the importance of the moment of resin burning with the abundant production of soot. However, the possibility that there were other unknown areas of application of gali-pot obtained from coniferous trees is not excluded. In any case, it is safe to say that the early Neolithic population living in the Ishim area purposefully used natural resins in their activities.

The processes occurring under the irradiation of FP9120 diazoquinone–novolac resist films on silicon with 60Co γ-rays have been studied by attenuated total reflectance (ATR) FTIR spectroscopy. It has been found that a significant modification of the ATR spectra of the photoresist films was noticeable only at absorbed doses above 200 kGy, and it occurred due to the radiation-induced transformations of methyl, methylene, hydroxymethyl, and phenoxyl groups of phenol–formaldehyde resin and o-naphthoquinone diazide (a photosensitive component). At the same time, the ATR spectra exhibited no signs of the destruction of aromatic fragments in the resist at doses to 300 kGy. In the region of the stretching vibrations of C=O bonds, a decrease in the maximum intensity of a band at ~1700 cm–1 was observed upon irradiation with its simultaneous broadening and shift to the high-energy region by ~30 cm–1 due to a change in the nearest environment of the C=O group. An increase in the absorption band intensity at 1650 cm–1 indicated the accumulation of formaldehyde upon the γ-irradiation of the resist as a result of the fragmentation of hydroxymethyl residues in the phenol–formaldehyde resin. [ABSTRACT FROM AUTHOR]

Abstract Because the maximum temperature reached in the slip zone is significant information for understanding slip behaviors during an earthquake, the maturity of carbonaceous material (CM) is widely used as a proxy for detecting frictional heat recorded by fault rocks. The degree of maturation of CM is controlled not only by maximum temperature but also by the heating rate. Nevertheless, maximum slip zone temperature has been estimated previously by comparing the maturity of CM in natural fault rocks with that of synthetic products heated at rates of about 1 °C s−1, even though this rate is much lower than the actual heating rate during an earthquake. In this study, we investigated the kinetic effect of the heating rate on the CM maturation process by performing organochemical analyses of CM heated at slow (1 °C s−1) and fast (100 °C s−1) rates. The results clearly showed that a higher heating rate can inhibit the maturation reactions of CM; for example, extinction of aliphatic hydrocarbon chains occurred at 600 °C at a heating rate of 1 °C s−1 and at 900 °C at a heating rate of 100 °C s−1. However, shear-enhanced mechanochemical effects can also promote CM maturation reactions and may offset the effect of a high heating rate. We should thus consider simultaneously the effects of both heating rate and mechanochemistry on CM maturation to establish CM as a more rigorous proxy for frictional heat recorded by fault rocks and for estimating slip behaviors during earthquake.

Mass spectrometry with negative-ion electrospray ionization proves the existence of not only monomers of α-lipoic acid (LA) but also its dimers and trimers in the aqueous phase. Upon incubation with ferrous ions (0.1 mM), new mass ions at m/z 261, 467, and 727 appear in the mass chromatogram in the positive ionization mode, and a mass ion at m/z 671 appears in the negative ionization mode. These mass ions are complexes of LA with ferrous ions, formed due to coordination bonds. The presence of complexes depends on the LA concentration. At concentrations of 0.25 to 4.00 mM, four complexes are observed. LA at a concentration of 4 mM (the maximum concentration that can be achieved by dissolving the acid in water) in the presence of 1 mM of hydrogen peroxide and 0.1 mM of Fe2+ inhibits phospholipid oxidation by 25%. Such an effect was not observed at the LA concentrations below 4 mM. At a concentration of 0.06 mM, only one complex with iron ions is formed (m/z 261). We found by IR spectroscopy that in the presence of iron ions and hydrogen peroxide, one or both sulfur atoms in the LA molecule are oxidized by the hydroxyl radical. The results suggest two mechanisms for the implementation of the antioxidant properties of LA: oxidation by a hydroxyl radical and chelation of ferrous ions. [ABSTRACT FROM AUTHOR]

The communication presents the results of a study on the hydrothermal conversion of heavy super-viscous crude oil in presence of Al2O3, Fe2O3, NiCO3, and ZnO nanoparticles at temperatures in the range of 350°С - 375°С and pressure varying from 5.2 MPa to 21 MPa. The general pattern of the super-viscous crude oil hydrothermal conversion refers to an increase of the content of low-boiling compounds and saturated hydrocarbons due to the destruction of the tar-asphaltene substances and the polyaromatic compounds present in the initial oil leading to a decrease of its viscosity. The lowest viscosity of 2.81 Pa×s observed at 10°C is achieved in the presence of Fe2O3 nanoparticles at a temperature of 375°C and pressure of 18 MPa. [ABSTRACT FROM AUTHOR]

Compounds BaLaInO4 and BaLaIn0.9Nb0.1O4.1 with the Ruddlesden–Popper structure, are synthesized. The ability of these phases with respect to hydration is shown. It is demonstrated that doping does not alter the type of proton-containing particles, and three types of energy non-equivalent hydroxyl groups are the only kinds of oxygen−hydrogen groups. It is established that introducing niobium raises the level of hydration with respect to undoped compositions, due to an increase in the fraction of isolated ОН– groups located in a salt block. [ABSTRACT FROM AUTHOR]

The article presents a review of studies carried out mainly by the researchers of the Ufa State Petroleum Technological University, which are aimed at detection of new properties of carbon in such condensed media as petroleum and coal pitches, steels and cast irons. Carbon plays an important role in the industry of construction materials being a component of road and roof bitumen and setting the main mechanical properties of steels. It was determined that crystal-like structures appear in classical glass-like substances – pitches which contain several thousands of individual hydrocarbons of various compositions. That significantly extends the concept of crystallinity. In structures of pitches, the control parameter of the staged structuring process is paramagnetism of condensed aromatic hydrocarbons. Fullerenes were detected in steels and cast irons and identified by various methods of spectrometry and microscopy. Fullerene С60, which contains 60 carbon atoms, has diameter of 0,7 nm and is referred to the nanoscale objects, which have a significant influence on the formation of steel and cast iron properties. It was shown that fullerenes appear at all stages of manufacture of cast irons; they are formed during introduction of carbon from the outside, during crystallization of metal in welded joints. Creation of modified fullerene layers in steels makes it possible to improve anticorrosion and tribological properties of structural materials. At the same time, outside diffusion of carbon from the carbon deposits on the metal surface also leads to formation of additional amount of fullerenes. This creates conditions for occurrence of local microdistortions of the structure, which lead to occurrence of cracks. Distribution of fullerenes in iron matrix is difficult to study as the method is labor-intensive, it requires dissolution of the matrix in the hydrofluoric acid and stage fullerene separation with further identification by spectral methods.

Steels of various purposes are used in the construction industry, for example, as the reinforcement material in reinforced concrete structures. In the oil and gas industry, steel structures are used for storage and transportation of explosive toxic media. In this case the catastrophic damages might take place, that points at insufficiently deep knowledge about the processes running in structural materials when load is applied. Recent studies show that many properties of steel are set at the nanoscale level during crystallization from the molten metal and thermal treatment. To detect and identify fullerenes С60 and С70, which are independent nanoscale objects in steel structure, by various methods requires studying of how these objects influence on formation of steel properties. Iron atoms can serve as a catalyst and, interacting with large aromatic structures or fragments of the graphite planes, they form voluminous fullerene-type structures. The inverse phenomenon, i.e. influence of the formed nanoscale objects on structuring of the iron atoms, is also possible, as fullerene size is comparable with the size of the stable nucleus of the iron crystalline phase. The article discusses the issue of mechanisms of fullerenes formation in steels and cast irons. The most complicated issue in the study is the fullerenes identification by spectral methods as the quantity of released molecules is small. In order to increase the sensitivity of the fullerenes IR-spectrometry method, potassium bromide has been proposed to use. Dried and reduced sediment obtained as a result of dissolving iron matrix in steels is mixed with potassium bromide, the mixture becomes bright-orange. This fact points to presence of bromic fullerenes and to presence of fullerenes in the studied specimens. It is shown that the offered specimen preparation algorithm significantly increases sensitivity of the method.

Aim. To analyze the carbonyl derivatives of 7-((3-thio-4-R-4H-1,2,4-triazole-5-yl)methyl)theophylline their mother substance was synthesized and its interaction with α-haloketones series was carried out. Methods and results. The physical-chemical properties of the obtained compounds have been studied and their structures have been confirmed by elemental analysis, infrared spectrometry, 1H NMR spectrometry, UV spectrophotometry and gas chromatography mass spectrometry. Preliminary computer study of acute toxicity and biological activity has been also carried out. It has been determined that the obtained compounds may exhibit diuretic and analeptic activity and 1,2,4-triazole fragment can theoretically increase it. Conclusion. Preliminary prediction of acute toxicity has showed that the compounds are low-toxic.

In the temperature range 16–100 K, IR spectrometric studies of thermally stimulated transformations in cryocondensed Freon 134a films were carried out. It was found that Freon 134a cryofilms, formed at T = 16 K, under heating range from 70 to 90 K undergo multiple structural transformations of various nature. It was concluded that at a temperature of T g  = 72 K, takes place the glassy state transition to the supercooled liquid (G-SCL). At about T = 78 K, crystallization of SCL begins the state of an orientationally disordered plastic crystal. At a transition temperature T trans  = 80 K, a second quasi-glass transition occurs from the state of the orientation glass to a plastic crystal with an ordered rotational subsystem. Within temperature range 83–85 K, a plastic crystal-monoclinic crystal phase transition takes place. [ABSTRACT FROM AUTHOR]

One of the promising ways of expanding energy resource base is production of combustible gas from coalbeds. The yield of gaseous components from samples of Visean coals of Tatarstan upon thermal impact was studied in this work by combined thermogravimetric and IR spectrometric method. It is demonstrated that methane begins to appear actively at 384-405°C, depending on the test coal sample. In this process, the yield of methane could be as much as 30 wt. % and higher, which confirms the prospect of getting gaseous fuel from Visean coal deposits by thermal impact. [ABSTRACT FROM AUTHOR]

Qualitative studies were performed, and the feasibility of ethanol fluorination by its reactions with anhydrous HF and UF6 was demonstrated. The reaction occurs at temperatures of up to 150°С via replacement of OH groups with probable formation of Freon 161 and substitution of СH groups with the most probable formation of Freon 152. The Freons were identified by IR spectroscopy. The solid reaction products mainly consist of intermediate uranium fluorides. The formation of uranyl fluoride is not proved unambiguously. [ABSTRACT FROM AUTHOR]

Biperiden hydrochloride, (1RS)-1-[(1RS, 2SR, 4RS)-bicyclo[2.2.1]hept-5-en-2-yl]-1-phenyl-3-(piperidin-1-yl)prop an-1-ol hydrochloride, is one of the most efficacious cholinolytics. It is used to treat Parkinson’s disease and various types of muscular spasms and to ameliorate uncoordinated muscular movements that can accompany the use of several tranquilizers [1, 2]. Biperiden appears in the vital and essential drug list that was approved by an order of the RF Government [3]. [ABSTRACT FROM AUTHOR]

In the present work, different types of castor biodiesels were synthesized by using slow pyrolysis process of raw castor oil in the presence of different types of catalysts. These catalysts as anhydrous sodium hydroxide (NaOH), alumina (Al 2 O 3 ), sodium carbonate (Na 2 CO 3 ), potassium hydroxide (KOH) and molecular sieve catalyst zeolite (ZMS-5) combined with anhydrous sodium hydroxide (ZMS-5 combined with NaOH) were used for yielding these biodiesels. So, the effects of variation of the catalyst type and its concentration on both yield of castor biodiesels and the pyrolysis temperature ranges were investigated. It was noticed that through the pyrolysis process, two grades of synthesized biodiesels were obtained in the presence of different types of catalysts. The first at the start of the pyrolysis was yellowish one, termed as Castor Biodiesel Number 1 (CBD1). And the second type was brownish biodiesel, called as Castor Biodiesel Number 2 (CBD2), while the rest was the black and heaviest, termed as bio-mazot. It was found that the highest total yields of biodiesels were obtained in the presence of 1% by volume of both NaOH and ZMS-5 combined with NaOH. Thus, four biodiesels were yielded and termed as CBD1 h , CBD2 h , CBD1 hz , CBD2 hz . And the different physical properties of these four biodiesels were measured according to American Society of Testing Material (ASTM). Also, the chemical compositions of these four biodiesels were determined by using Gas Chromatography Mass (GC-Ms) spectrum as well as the functional groups using Infra-Red (IR) spectrum. In addition, the performance of a single cylinder four stroke direct injection compression ignition engine fueled by two different blends as 5 and 10% by volume of CBD h and CBD hz with gas oil was measured. Thus, the main conclusion was derived from both physical and chemical investigations as well as engine performance that these synthesized biodiesels could be used as a good alternative of gas oil. [ABSTRACT FROM AUTHOR]

This study identified and quantified microplastics in the Bay of Asunción, Paraguay, and its main tributaries. Surface water samples were sieved in duplicate at six locations using stainless-steel sieves (0.3–4.75 mm range), digested employing the Fenton's reaction (Fe-catalysed H 2 O 2 digestion), and floated using NaCl and NaI. Particles were inspected using a microscope and characterized by IR spectrometry. Microplastics were found in all samples; more abundant (p < 0.05) in water from the bay (13.2 ± 13.4 items·m−3) than from the tributaries (1.0 ± 0.5 items·m−3). Most microplastics were common polymers and their abundance was in the order polypropylene > high-density polyethylene > low-density polyethylene, transparent and white. The results were similar to other regional studies and suggested that their main source was single-use packaging, disposed inadequately due to poor garbage collection. [Display omitted] • Two NaCl and NaI flotations recover microplastics from water of tributaries. • Microplastics appear in all samples from the Bay of Asunción, which accumulate them. • Microplastics main sources seemed packaging plastics. • The tributaries discharge around 3 microplastics·m−3 to the Bay. • Transparent and white Polypropylene and Polyethylene fragments predominate. [ABSTRACT FROM AUTHOR]

We proposed a procedure for the IR spectrometric determination of lipid hydroperoxides in biological systems. The main bands in the IR absorption spectra of linoleic acid and its hydroperoxide were identified, and analytical bands suitable for the determination of both compounds in their mixtures were selected. It was demonstrated that tert-butyl hydroperoxide can be used as an external standard for determining fatty acid hydroperoxides. Using the external standard method (calibration curve) for tert-butyl hydroperoxides, we calculated the concentration of linoleic acid hydroperoxide in its mixture with linoleic acid; it agreed with the specified values. Using the developed procedure, we estimated the concentration of hydroperoxide groups in natural cardiolipin. The results were compared to those obtained by an independent method (activated chemiluminescence). [ABSTRACT FROM AUTHOR]

The structure of the glass obtained by incorporation of the residue from reprocessing of the spent extractant, tributyl phosphate, into sodium aluminophosphate glass and the structural state of uranium in this glass were studied by vibration (IR, Raman) and X-ray absorption (XAFS) spectroscopy. An IR and Raman spectroscopic study shows that the structural network of the glasses is formed by ortho- and pyrophosphate groups linked by tetrahedral AlO units. As follows from the XAFS data, uranium is present in the glass in the form of uranyl ions and of separate UO particles. The glass has high hydrolytic durability: The uranium leach rate determined in accordance with GOST (State Standard) R 52 126-2003 is of the order of 10 g cm day. [ABSTRACT FROM AUTHOR]

It has been proven on the example of individual hydrocarbons that IR spectrometry can be used to analyze properties of base oils. A proximate viscosity, viscosity index, and pour point determination method was developed based on quantitative IR spectrometry using the areas of two characteristic peaks and regression analysis for API-classified group 3 and 4 oils. This method can be used for quality control and real-time study of base oils. [ABSTRACT FROM AUTHOR]

The paper examines the influence of moisture and temperature cycles on timber elements reinforced with a wet lay-up system composed of various fibrous materials (carbon, flax) and matrices (epoxy resin, vinyl glue). A multi-scale experimental approach was adopted, including: (i) mechanical characterization of the composite reinforcement systems; (ii) investigation of behavior at the composite-to-timber interface by mechanical bond tests and microstructural analyses; (iii) four-point bending tests on strengthened timber beams. The results highlighted the good performance of natural-fiber composites compared with synthetic ones, and the marked influence of wood moisture content and temperature on bonding. [ABSTRACT FROM AUTHOR]

The adverse effects of microplastics (MP) found in food on the health have recently been recognized as a new source of human health risks. In order to evaluate and minimize them, it is necessary to evaluate the exposure using sensitive and specific methods. The aim of the research was the substantiation of methodological approaches to the identification and quantification of microplastics in food based on the analysis of literature data. Material and methods . Literature selection was carried out using the PubMed international reference database for the period from 2014 to 2023 using keywords corresponding to the context of the research theme. A total of 159 sources were selected, of which 94 original and review papers were included in the review according to the criteria of their relevance to the problem under consideration, scientific reliability and completeness. Results . At present, various approaches have been developed that make it possible to isolate MPs from complex bioorganic matrices (such as, for example, seafood), classify them by chemical composition, and quantify their content through the mass or number of particles. Among the most developed physic-chemical methods for the analysis of MPs are Fourier transform IR spectrometry and Raman microspectrometry, pyrolysis gas chromatography - mass spectrometry, thermogravimetric analysis, as well as approaches based on liquid chromatography, microfluorimetry, analytical scanning and transmission electron microscopy and others. Unsolved problems in the field of MP research in food include the high laboriousness and low performance of the identification technologies used, the lack of reference and standard samples of MP, the complexity of the equipment used, which makes it difficult to use it for routine hygienic control. The issue of the influence of MP aging degree on the results of its qualitative and quantitative determination has not been sufficiently studied. Some hopes in the field of development of rapid analysis of MTs are pinned on the use of aptamers. Conclusion . Existing analytical methods make it possible to determine the content of MPs in environmental objects, but further improvement and validation of these methods is required in relation to the assessment of the content of MPs in various types of food., Competing Interests: The author declares no conflicts of interest., (Copyright© GEOTAR-Media Publishing Group.)

Spectrometry in the visible and IR regions is used to study complex formation in aqueous solutions of rhodanides of bivalent cations Cd, Hg, Ni, Mn, Fe, Zn, and Co. It is found that Cd(II), Hg(II), Ni(II), and Fe(II) coordinate NCS by the thiocyanate type; Zn(II), by the isothiocyanate type; and Co(II) and Mn(II) change their coordination mode depending on the concentration of KNCS in the solution. The effect of the structure of metal rhodanide complexes on the selectivity of Zn(NCS) and Co(NCS)-selective electrodes (SE) is revealed. It is shown that hydrophobic ions of Zn(NCS) and ions (2.0 M)-Co(NCS), at high concentrations of KNCS (2.0 M) exhibit the strongest affinity to the membrane phase of electrodes. This ensures the selective potentiometric determination of zinc and cobalt on their simultaneous presence. [ABSTRACT FROM AUTHOR]

In order to understand plant functioning, plant community composition and terrestrial biogeochemistry it is decisive to study standing root biomass, (fine) root dynamics and interactions below ground. While most plant taxa can be identified by visual criteria above ground, roots show less distinctive features. Furthermore, root systems of neighbouring plants are rarely spatially segregated; thus, most soil horizons and samples hold roots of more than one species necessitating root sorting according to taxa.In the last decades, various approaches, ranging from anatomical and morphological analyses to differences in chemical composition and DNA sequencing were applied to discern species’ identity and biomass below ground. Among those methods, a variety of spectroscopic methods was used to detect differences in the chemical composition of roots. In this review, spectroscopic methods used to study root systems of herbaceous and woody species in excised samples or in situ will be discussed. In detail, techniques will be reviewed according to their usability to discern root taxa, to determine root vitality, and to quantify root biomass non-destructively or in soil cores holding mixtures of plant roots. In addition, spectroscopic methods which may be able to play an increasing role in future studies on root biomass and related traits are highlighted.

Raw or dried gallbladders of cyprinid fish have long been ingested as a traditional medicine in the Asian countries, particularly in China, for ameliorating visual acuity, rheumatism, and general health; however, sporadic poisoning incidences have occurred after their ingestion. The poisoning causes complex symptoms in patients, including acute renal failure, liver dysfunction, paralysis, and convulsions of limbs. The causative substance for the poisoning was isolated, and its basic properties were examined. The purified toxin revealed a minimum lethal dose of 2.6 mg/20 g in mouse, when injected intraperitoneally. The main symptoms were paralysis and convulsions of the hind legs, along with other neurological signs. Liver biopsy of the euthanized mice clearly exhibited hepatocytes necrosis and infiltration of neutrophils and lymphocytes, suggesting the acute dysfunction of the liver. Blood tests disclosed the characteristics of acute renal failure and liver injury. Infrared (IR) spectrometry, fast atom bombardment (FAB) mass spectrometry, and 1H- and 13C-nuclear magnetic resonance (NMR) analysis indicated, a molecular formula of C27H48O8S, containing a sulfate ester group for the toxin. Thus, we concluded that the structure of carp toxin to be 5α-cyprinol sulfate (5α-cholestane-3α, 7α, 12α, 26, 27-pentol 26-sulfate). This indicated that carp toxin is a nephro- and hepato- toxin, which could be the responsible toxin for carp bile poisoning in humans. [ABSTRACT FROM AUTHOR]

A method is developed for determining N-phosphonomethyl glycine (glyphosate) in the oxidation products of N-phosphonomethyl iminodiacetic acid (PMIDA) by IR spectrometry. In the IR spectra of glyphosate and PMIDA characteristic bands at 1562 and 721 cm, respectively, are revealed; based on absorbance at these wavelength, quantitative determination of glyphosate in the presence of PMIDA is possible. For model mixtures a correlation is revealed between the actual glyphosate concentration and the one derived from absorbance at characteristic bands. As shown, NMR (H, P) and IR spectrometry yield comparable results. The method is verified by an analysis of the final product prepared by liquid-phase oxidation of PMIDA to glyphosate using hydrogen peroxide and may be utilized in quality control in its manufacture. [ABSTRACT FROM AUTHOR]

In order to understand plant functioning, plant community composition, and terrestrial biogeochemistry, it is decisive to study standing root biomass, (fine) root dynamics, and interactions belowground. While most plant taxa can be identified by visual criteria above-ground, roots show less distinctive features. Furthermore, root systems of neighboring plants are rarely spatially segregated; thus, most soil horizons and samples hold roots of more than one species necessitating root sorting according to taxa. In the last decades, various approaches, ranging from anatomical and morphological analyses to differences in chemical composition and DNA sequencing were applied to discern species' identity and biomass belowground. Among those methods, a variety of spectroscopic methods was used to detect differences in the chemical composition of roots. In this review, spectroscopic methods used to study root systems of herbaceous and woody species in excised samples or in situ will be discussed. In detail, techniques will be reviewed according to their usability to discern root taxa, to determine root vitality, and to quantify root biomass non-destructively or in soil cores holding mixtures of plant roots. In addition, spectroscopic methods which may be able to play an increasing role in future studies on root biomass and related traits are highlighted. [ABSTRACT FROM AUTHOR]

In the field of thermogravimetric analysis, the evolved gas analysis is a hyphenated technique which allows an easy and rapid identification of the gaseous products resulting from thermodegradation under non-isothermal conditions. In the present paper, the relationships between the Gramm-Schmidt profile (GS) and the DTG curve (d m/d t) will be theoretically analyzed. So, there are two curves which have the extreme points at the same time (temperature) values and which have complementary concavity and convexity. By complex parallel processes, the relationship is more complex from the mathematical point of view. The discussed theoretic cases are connected with the experimental data obtained through the thermal analysis of aminophenazone, glycyrrhetinic acid, amlodipine maleate, verapamil, and a technical polymethane. [ABSTRACT FROM AUTHOR]

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Analysis of gas chromatography-mass spectrometry and IR spectrometry shows that the composition of organic impurities in stream and water bodies of the Tom’ basin depends on natural and anthropogenic factors. The anthropogenic load is especially important, as the organic impurities originating from oil (paraffins, isoparaffins, naphthenes, aromatic hydrocarbons) are predominant; other pollutants of anthropogenic origin are also present (phthalates, carboxylic acids and their esters, phosphates). The composition of organic pollutants dumped into the river from each industrial zone has been analyzed both qualitatively and quantitatively. [ABSTRACT FROM AUTHOR]

Samples collected in a foundry were used to analyze sources of variation and factors influencing the overall accuracy of sampling results. Air samples were analyzed by Fourier Transform Infrared Spectroscopy (FTIR) using NIOSH Method 7602 to study particle size effects, analytical precision, sampling equipment performance, and production factors. The FTIR technique provides accuracy when silica particle size is taken into consideration. In this case, the variability due to analytical factors is small compared with other sources of error. The typical coefficient of variation of the analytical procedure is 0.08; variation associated with sampling reaches 0.21; and interday coefficient of variation can be as high as 0.48. The IR method has advantages over XRD analysis, including cost effectiveness, sensitivity, and a lower detection limit. [ABSTRACT FROM AUTHOR]