Pub Date : 2023-01-01DOI: 10.26907/2542-064x.2023.1.83-93
L. G. Shaidarova, I. Chelnokova, D. Koryakovtseva, H. Budnikov
The Au–Bi binary system electrodeposited on the surface of a glassy carbon electrode exhibits catalytic activity during the electrooxidation of phenylephrine, paracetamol, and caffeine that enhances the peak currents and decreases overvoltage in the oxidation of organic compounds. The potential difference between the peaks of oxidation on the modified electrode is 400 mV for phenylephrine and paracetamol and 300 mV for phenylephrine and caffeine, respectively. The possibility of simultaneous voltammetric determination of phenylephrine, paracetamol, and caffeine on the glassy carbon electrode modified by the Au–Bi binary system was established. The calibration curve is linear in the concentration range from 5·10–6 to 5·10–3 M. The developed method was tested in the analysis of combined drugs.
{"title":"Electrode with the Electrodeposited Gold–Bismuth Binary System for Voltammetric Determination of Phenylephrine, Paracetamol, and Caffeine","authors":"L. G. Shaidarova, I. Chelnokova, D. Koryakovtseva, H. Budnikov","doi":"10.26907/2542-064x.2023.1.83-93","DOIUrl":"https://doi.org/10.26907/2542-064x.2023.1.83-93","url":null,"abstract":"The Au–Bi binary system electrodeposited on the surface of a glassy carbon electrode exhibits catalytic activity during the electrooxidation of phenylephrine, paracetamol, and caffeine that enhances the peak currents and decreases overvoltage in the oxidation of organic compounds. The potential difference between the peaks of oxidation on the modified electrode is 400 mV for phenylephrine and paracetamol and 300 mV for phenylephrine and caffeine, respectively. The possibility of simultaneous voltammetric determination of phenylephrine, paracetamol, and caffeine on the glassy carbon electrode modified by the Au–Bi binary system was established. The calibration curve is linear in the concentration range from 5·10–6 to 5·10–3 M. The developed method was tested in the analysis of combined drugs.","PeriodicalId":23418,"journal":{"name":"Uchenye Zapiski Kazanskogo Universiteta. Seriya Estestvennye Nauki","volume":null,"pages":null},"PeriodicalIF":0.3,"publicationDate":"2023-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"82858954","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2023-01-01DOI: 10.26907/2542-064x.2023.1.149-157
F. Karataeva, I. Rakhmatullin, N. F. Galiullina, V. Klochkov
The structure and intramolecular mobility of some derivatives of bis(thio)phosphorylated amides in CCl4, CD2Cl2, and CD3CN solutions were examined by 1H and 31P NMR spectroscopy. A comparative analysis of the temperature-dependent 1H and 31P NMR spectra of the studied compounds with symmetric and asymmetric substitution at phosphorus atoms was carried out. Various intramolecular processes were identified – rotation around C-N bonds, conformational transformations of molecules, tautomerism, and phosphorylotropic rearrangement with the formation of various conformational forms. It was shown that a dynamic equilibrium of several forms is reached, with the amide (phosphazo-) form having a clear advantage.
{"title":"Structure and Intramolecular Mobility of Some Derivatives of Bis(thio)phosphorylated Amides in CCL4, CD2CL2, and CD3CN Solutions","authors":"F. Karataeva, I. Rakhmatullin, N. F. Galiullina, V. Klochkov","doi":"10.26907/2542-064x.2023.1.149-157","DOIUrl":"https://doi.org/10.26907/2542-064x.2023.1.149-157","url":null,"abstract":"The structure and intramolecular mobility of some derivatives of bis(thio)phosphorylated amides in CCl4, CD2Cl2, and CD3CN solutions were examined by 1H and 31P NMR spectroscopy. A comparative analysis of the temperature-dependent 1H and 31P NMR spectra of the studied compounds with symmetric and asymmetric substitution at phosphorus atoms was carried out. Various intramolecular processes were identified – rotation around C-N bonds, conformational transformations of molecules, tautomerism, and phosphorylotropic rearrangement with the formation of various conformational forms. It was shown that a dynamic equilibrium of several forms is reached, with the amide (phosphazo-) form having a clear advantage.","PeriodicalId":23418,"journal":{"name":"Uchenye Zapiski Kazanskogo Universiteta. Seriya Estestvennye Nauki","volume":null,"pages":null},"PeriodicalIF":0.3,"publicationDate":"2023-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"78918590","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2023-01-01DOI: 10.26907/2542-064x.2023.2.190-203
L. Lopukhov, A. V. Laikov, I. Salafutdinov, V. Romanova, V. L. Lopukhov, T. Grigoryeva, L. Gaysina, J. Oslopova, D. Safina, I. H. Valeeva, S. Abdulkhakov, R. Faizullin, A. Kiyasov
The effects of acrolein and crotonaldehyde on the health of Russian smokers upon switching to heated tobacco product use were analyzed in a five-day randomized clinical trial. The findings suggest that heated tobacco products significantly reduce exposure to these toxicants, with the adverse effects becoming less pronounced in just one day and comparable to complete cessation of smoking. The dynamics of nicotine intake and metabolism in the smokers who switched to heated tobacco products remained stable throughout the study and was similar to that in the group of regular cigarette smokers. Therefore, our study, which has been performed for the first time among the Russian population, shows that smokers switching to heated tobacco products are less exposed to harmful chemicals like acrolein and crotonaldehyde and thus may be protected against some of the negative health effects often associated with regular cigarettes.
{"title":"Insights into the Health Effects of Acrolein and Crotonaldehyde in Russian Smokers Switching from Regular Cigarettes to Heated Tobacco Products","authors":"L. Lopukhov, A. V. Laikov, I. Salafutdinov, V. Romanova, V. L. Lopukhov, T. Grigoryeva, L. Gaysina, J. Oslopova, D. Safina, I. H. Valeeva, S. Abdulkhakov, R. Faizullin, A. Kiyasov","doi":"10.26907/2542-064x.2023.2.190-203","DOIUrl":"https://doi.org/10.26907/2542-064x.2023.2.190-203","url":null,"abstract":"The effects of acrolein and crotonaldehyde on the health of Russian smokers upon switching to heated tobacco product use were analyzed in a five-day randomized clinical trial. The findings suggest that heated tobacco products significantly reduce exposure to these toxicants, with the adverse effects becoming less pronounced in just one day and comparable to complete cessation of smoking. The dynamics of nicotine intake and metabolism in the smokers who switched to heated tobacco products remained stable throughout the study and was similar to that in the group of regular cigarette smokers. Therefore, our study, which has been performed for the first time among the Russian population, shows that smokers switching to heated tobacco products are less exposed to harmful chemicals like acrolein and crotonaldehyde and thus may be protected against some of the negative health effects often associated with regular cigarettes.","PeriodicalId":23418,"journal":{"name":"Uchenye Zapiski Kazanskogo Universiteta. Seriya Estestvennye Nauki","volume":null,"pages":null},"PeriodicalIF":0.3,"publicationDate":"2023-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"73158469","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2023-01-01DOI: 10.26907/2542-064x.2023.2.231-262
G. Galieva, P. Galitskaya, S. Selivanovskaya
Microorganisms play an important role in the growth and development of a plant throughout its entire life cycle. Recent advances in the methods of molecular biological analysis have expanded our understanding of the composition and functions of plant microbiota (epiphytic, rhizosphere, and endosphere) and the molecular mechanisms associated with specific processes that govern plant-microorganism interactions. This article reviews the types of plant microbial communities, their sources of origin, and species composition, as well as the critical role they play in modulating the plant immune response against phytopathogens, improving the elemental nutrition of plants, scaring away herbivorous animals, producing phytohormones, and enabling plants to thrive under extreme environmental conditions.
{"title":"Plant Microbiome: Origin, Composition, and Functions","authors":"G. Galieva, P. Galitskaya, S. Selivanovskaya","doi":"10.26907/2542-064x.2023.2.231-262","DOIUrl":"https://doi.org/10.26907/2542-064x.2023.2.231-262","url":null,"abstract":"Microorganisms play an important role in the growth and development of a plant throughout its entire life cycle. Recent advances in the methods of molecular biological analysis have expanded our understanding of the composition and functions of plant microbiota (epiphytic, rhizosphere, and endosphere) and the molecular mechanisms associated with specific processes that govern plant-microorganism interactions. This article reviews the types of plant microbial communities, their sources of origin, and species composition, as well as the critical role they play in modulating the plant immune response against phytopathogens, improving the elemental nutrition of plants, scaring away herbivorous animals, producing phytohormones, and enabling plants to thrive under extreme environmental conditions.","PeriodicalId":23418,"journal":{"name":"Uchenye Zapiski Kazanskogo Universiteta. Seriya Estestvennye Nauki","volume":null,"pages":null},"PeriodicalIF":0.3,"publicationDate":"2023-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"89385004","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2023-01-01DOI: 10.26907/2542-064x.2023.1.133-148
A. Khabibrakhmanova, E. S. Rabbanieva, D. Gerasimova, O. Lodochnikova, L. Latypova, A. Kurbangalieva
Novel disulfinyl derivatives based on 3,4-dichloro-2(5H)-furanone, aliphatic dithiols, and monoterpene alcohols were synthesized. Chiral bis-thioethers in the molecules of which the dithiol fragment links two five-membered cycles at C4 atoms were obtained in the reactions of 5(S)-(l-menthyloxy)- and 5(S)-(l-bornyloxy)-2(5H)-furanones with ethane-1,2-dithiol and propane-1,3-dithiol in acetone in basic medium. The action of an excess of m-chloroperoxybenzoic acid (2.0–3.2 equiv.) on bis-thioethers led to the formation of the corresponding mono- and disulfoxides bearing l-menthol or l-borneol fragments at the 5th position of the lactone ring. The methods of column chromatography and fractional recrystallization were used for the isolation of individual products. The structure of the synthesized heterocycles was proved by IR and NMR spectroscopy, and their composition was confirmed by high-resolution mass spectrometry. The molecular structure of the three disulfoxides was characterized by X-ray diffraction analysis.
{"title":"Oxidation of Chiral 2(5H)-Furanone Bis-Thioethers to Disulfoxides","authors":"A. Khabibrakhmanova, E. S. Rabbanieva, D. Gerasimova, O. Lodochnikova, L. Latypova, A. Kurbangalieva","doi":"10.26907/2542-064x.2023.1.133-148","DOIUrl":"https://doi.org/10.26907/2542-064x.2023.1.133-148","url":null,"abstract":"Novel disulfinyl derivatives based on 3,4-dichloro-2(5H)-furanone, aliphatic dithiols, and monoterpene alcohols were synthesized. Chiral bis-thioethers in the molecules of which the dithiol fragment links two five-membered cycles at C4 atoms were obtained in the reactions of 5(S)-(l-menthyloxy)- and 5(S)-(l-bornyloxy)-2(5H)-furanones with ethane-1,2-dithiol and propane-1,3-dithiol in acetone in basic medium. The action of an excess of m-chloroperoxybenzoic acid (2.0–3.2 equiv.) on bis-thioethers led to the formation of the corresponding mono- and disulfoxides bearing l-menthol or l-borneol fragments at the 5th position of the lactone ring. The methods of column chromatography and fractional recrystallization were used for the isolation of individual products. The structure of the synthesized heterocycles was proved by IR and NMR spectroscopy, and their composition was confirmed by high-resolution mass spectrometry. The molecular structure of the three disulfoxides was characterized by X-ray diffraction analysis.","PeriodicalId":23418,"journal":{"name":"Uchenye Zapiski Kazanskogo Universiteta. Seriya Estestvennye Nauki","volume":null,"pages":null},"PeriodicalIF":0.3,"publicationDate":"2023-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"82313973","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2023-01-01DOI: 10.26907/2542-064x.2023.2.204-215
E. V. Uzlova
Neuroglobin (Ngb) is a member of the globin family. Like other globin proteins, it is involved in the maintenance of oxygen homeostasis. Ngb distribution in the normal brain is well known, but its response to pathological injury, such as cerebral ischemia, has not yet been adequately elucidated. One primary reason for this is that ischemic lesions in cerebral tissues have mostly been studied in transgenic organisms. In addition, the available data on Ngb content are limited to a small number of brain structures. This article examines the patterns of changes in Ngb immunoreactivity in neurons from different parts of the rat brain after subtotal cerebral ischemia of varying duration. An immunohistochemical study of Ngb content in 25 brain structures of white male Wistar rats exposed to 30-min and 3-h subtotal cerebral ischemia was performed. A decrease in Ngb content in all structures (especially 3 h after the ischemia onset and in the phylogenetically older parts), temporal mediation, and dependence on the phylogenetic age were revealed. The obtained results further decipher the correlation between the changes in Ngb content and the degree of cerebral ischemic damage, which is necessary to clarify the functions of the studied protein.
{"title":"Neuroglobin Content in Rat Brain Structures after Subtotal Cerebral Ischemia","authors":"E. V. Uzlova","doi":"10.26907/2542-064x.2023.2.204-215","DOIUrl":"https://doi.org/10.26907/2542-064x.2023.2.204-215","url":null,"abstract":"Neuroglobin (Ngb) is a member of the globin family. Like other globin proteins, it is involved in the maintenance of oxygen homeostasis. Ngb distribution in the normal brain is well known, but its response to pathological injury, such as cerebral ischemia, has not yet been adequately elucidated. One primary reason for this is that ischemic lesions in cerebral tissues have mostly been studied in transgenic organisms. In addition, the available data on Ngb content are limited to a small number of brain structures. This article examines the patterns of changes in Ngb immunoreactivity in neurons from different parts of the rat brain after subtotal cerebral ischemia of varying duration. An immunohistochemical study of Ngb content in 25 brain structures of white male Wistar rats exposed to 30-min and 3-h subtotal cerebral ischemia was performed. A decrease in Ngb content in all structures (especially 3 h after the ischemia onset and in the phylogenetically older parts), temporal mediation, and dependence on the phylogenetic age were revealed. The obtained results further decipher the correlation between the changes in Ngb content and the degree of cerebral ischemic damage, which is necessary to clarify the functions of the studied protein.","PeriodicalId":23418,"journal":{"name":"Uchenye Zapiski Kazanskogo Universiteta. Seriya Estestvennye Nauki","volume":null,"pages":null},"PeriodicalIF":0.3,"publicationDate":"2023-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"84175294","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2023-01-01DOI: 10.26907/2542-064x.2023.2.322-339
M.G. Fazlyyyakhmatov, I. N. Shamanov, B. V. Sakharov, N. M. Khasanova, M. Varfolomeev, G. Samosorov, M. Pastukhov
Molecular group composition analysis of mineral oils is helpful to predict the performance of a future lubricant and to assess the compatibility of plasticizer oil with rubbers. The method of pulsed low-frequency NMR relaxation was used to determine the molecular group composition of 11 mineral oil samples, and the ratio of aromatic and non-aromatic hydrocarbons in them was calculated. NMR measurements were performed on a Chromatec-Proton 20M NMR analyzer with a 1H resonance frequency of 20 MHz. The method used consists in recording free induction decay signals, reconstructing the total signal amplitude, estimating the relative signal amplitude per unit mass of the sample, and calculating the proportion of aromatic hydrocarbons in the sample. The results were compared with those obtained by the standard chromatographic method. A high degree of correlation (R2 = 0.99) was observed between the results.
{"title":"Determination of the Aromatics Content in Mineral Oils by LF NMR","authors":"M.G. Fazlyyyakhmatov, I. N. Shamanov, B. V. Sakharov, N. M. Khasanova, M. Varfolomeev, G. Samosorov, M. Pastukhov","doi":"10.26907/2542-064x.2023.2.322-339","DOIUrl":"https://doi.org/10.26907/2542-064x.2023.2.322-339","url":null,"abstract":"Molecular group composition analysis of mineral oils is helpful to predict the performance of a future lubricant and to assess the compatibility of plasticizer oil with rubbers. The method of pulsed low-frequency NMR relaxation was used to determine the molecular group composition of 11 mineral oil samples, and the ratio of aromatic and non-aromatic hydrocarbons in them was calculated. NMR measurements were performed on a Chromatec-Proton 20M NMR analyzer with a 1H resonance frequency of 20 MHz. The method used consists in recording free induction decay signals, reconstructing the total signal amplitude, estimating the relative signal amplitude per unit mass of the sample, and calculating the proportion of aromatic hydrocarbons in the sample. The results were compared with those obtained by the standard chromatographic method. A high degree of correlation (R2 = 0.99) was observed between the results.","PeriodicalId":23418,"journal":{"name":"Uchenye Zapiski Kazanskogo Universiteta. Seriya Estestvennye Nauki","volume":null,"pages":null},"PeriodicalIF":0.3,"publicationDate":"2023-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"84350276","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2023-01-01DOI: 10.26907/2542-064x.2023.1.94-117
A. Kalmykova, E. N. Yakupova, F. Bekmuratova, I. Fitsev, G. Ziyatdinova, Denisovna, PhD Student of A.M Nailevna, Butlerov, Bekmuratova Feruzakhon, Mikhailovich, Ziyatdinova Guzel Kamilevna
Plants of the Lamiaceae family have been used for thousands of years in cooking, as well as phyto- and aromatherapy. Their essential oils are characterized by high antioxidant and other types of biological activities. In our study, the phytochemical profile and quantification of the essential oil components of thyme, marjoram, and sage were analyzed by gas chromatography with mass-spectrometric detection (GC-MSD). The antioxidant properties of the samples were evaluated using total antioxidant parameters (total antioxidant capacity (TAC), ferric reducing power (FRP), antioxidant activity (AOA) towards 2,2-diphenyl-1-picrylhydrazyl (DPPH•), and total phenolics by Folin–Ciocalteu method). The obtained FRP was 46–321-fold lower than TAC, which is consistent with the contents of phenolics identified in the samples. Terpenes, isopropylmethylphenols, and eugenol turned out to be the major components of all essential oils and determined their TAC and AOA. The Folin–Ciocalteu method was applicable to the thyme essential oil only. Its FRP, which is based on the reaction of phenolic antioxidants with electrogenerated ferricyanide ions, agreed well with the total phenolic contents (329 ± 17 and 334 ± 15 mg of carvacrol per mL, respectively). The thyme essential oil had the highest antioxidant parameters, while sage showed the weakest antioxidant properties. Positive correlations (r = 0.8846–0.9964) of the antioxidant parameters were obtained.
{"title":"Evaluation of the Antioxidant Properties and GC-MSD Analysis of Commercial Essential Oils from Plants of the Lamiaceae Family","authors":"A. Kalmykova, E. N. Yakupova, F. Bekmuratova, I. Fitsev, G. Ziyatdinova, Denisovna, PhD Student of A.M Nailevna, Butlerov, Bekmuratova Feruzakhon, Mikhailovich, Ziyatdinova Guzel Kamilevna","doi":"10.26907/2542-064x.2023.1.94-117","DOIUrl":"https://doi.org/10.26907/2542-064x.2023.1.94-117","url":null,"abstract":"Plants of the Lamiaceae family have been used for thousands of years in cooking, as well as phyto- and aromatherapy. Their essential oils are characterized by high antioxidant and other types of biological activities. In our study, the phytochemical profile and quantification of the essential oil components of thyme, marjoram, and sage were analyzed by gas chromatography with mass-spectrometric detection (GC-MSD). The antioxidant properties of the samples were evaluated using total antioxidant parameters (total antioxidant capacity (TAC), ferric reducing power (FRP), antioxidant activity (AOA) towards 2,2-diphenyl-1-picrylhydrazyl (DPPH•), and total phenolics by Folin–Ciocalteu method). The obtained FRP was 46–321-fold lower than TAC, which is consistent with the contents of phenolics identified in the samples. Terpenes, isopropylmethylphenols, and eugenol turned out to be the major components of all essential oils and determined their TAC and AOA. The Folin–Ciocalteu method was applicable to the thyme essential oil only. Its FRP, which is based on the reaction of phenolic antioxidants with electrogenerated ferricyanide ions, agreed well with the total phenolic contents (329 ± 17 and 334 ± 15 mg of carvacrol per mL, respectively). The thyme essential oil had the highest antioxidant parameters, while sage showed the weakest antioxidant properties. Positive correlations (r = 0.8846–0.9964) of the antioxidant parameters were obtained.","PeriodicalId":23418,"journal":{"name":"Uchenye Zapiski Kazanskogo Universiteta. Seriya Estestvennye Nauki","volume":null,"pages":null},"PeriodicalIF":0.3,"publicationDate":"2023-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"73429055","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2023-01-01DOI: 10.26907/2542-064x.2023.2.308-321
R. Kutygin, V. Makoshin
An extensive collection of fossil brachiopods, all assigned to the Wuchiapingian Stage, was recovered from the lower part of the Imtachan Formation along the Ustupnyi Creek (right tributary of the Setorym River) in the Southern Verkhoyanie. It comprises strophalosiids (Strophalosia? aff. vollossovitschi (Fredericks), Strophalosia? sp., Subtaeniothaerus lungersgauzeni Solomina, Marginalosia? magna Abramov et Grigorjeva), spiriferids (Crassispirifer monumentalis Abramov et Grigorjeva, Crassispirifer cf. monumentalis Abramov et Grigorjeva, Crassispirifer sp.), athyridids (Cleiothyridina nikolaevi Grunt, Cleiothyridina sp. 1, Bajtugania sp.), and terebratulids (Marinurnula? aff. mantuanensis (Campbell), Marinurnula? sp.). The identified assemblage is associated with brachiopods from the lower part of the Khalpirki Formation of the Western Verkhoyanie, the appearance of which marks the boundary between the Dulgalakhian and Khalpirkian Regional Stages and also substantiates the lower boundary of the Crassispirifer monumentalis Zone. Single finds of Crassispirifer cf. monumentalis in the lower part of the Middle Imtachan Subformation indicate that the entire lower subformation and the lower part of the middle subformation belong to the C. monumentalis Zone. There are no reliable finds of brachiopods at higher levels of the Imtachan Formation.
{"title":"Brachiopods of the Imtachan Formation in the Upper Permian of the Southern Verkhoyanie, Northeast Russia","authors":"R. Kutygin, V. Makoshin","doi":"10.26907/2542-064x.2023.2.308-321","DOIUrl":"https://doi.org/10.26907/2542-064x.2023.2.308-321","url":null,"abstract":"An extensive collection of fossil brachiopods, all assigned to the Wuchiapingian Stage, was recovered from the lower part of the Imtachan Formation along the Ustupnyi Creek (right tributary of the Setorym River) in the Southern Verkhoyanie. It comprises strophalosiids (Strophalosia? aff. vollossovitschi (Fredericks), Strophalosia? sp., Subtaeniothaerus lungersgauzeni Solomina, Marginalosia? magna Abramov et Grigorjeva), spiriferids (Crassispirifer monumentalis Abramov et Grigorjeva, Crassispirifer cf. monumentalis Abramov et Grigorjeva, Crassispirifer sp.), athyridids (Cleiothyridina nikolaevi Grunt, Cleiothyridina sp. 1, Bajtugania sp.), and terebratulids (Marinurnula? aff. mantuanensis (Campbell), Marinurnula? sp.). The identified assemblage is associated with brachiopods from the lower part of the Khalpirki Formation of the Western Verkhoyanie, the appearance of which marks the boundary between the Dulgalakhian and Khalpirkian Regional Stages and also substantiates the lower boundary of the Crassispirifer monumentalis Zone. Single finds of Crassispirifer cf. monumentalis in the lower part of the Middle Imtachan Subformation indicate that the entire lower subformation and the lower part of the middle subformation belong to the C. monumentalis Zone. There are no reliable finds of brachiopods at higher levels of the Imtachan Formation.","PeriodicalId":23418,"journal":{"name":"Uchenye Zapiski Kazanskogo Universiteta. Seriya Estestvennye Nauki","volume":null,"pages":null},"PeriodicalIF":0.3,"publicationDate":"2023-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"79210811","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2023-01-01DOI: 10.26907/2542-064x.2023.1.49-57
D. Gerasimova, L. V. Frantsuzova, R. Fayzullin, O. Lodochnikova
A theoretical study of the association of phenyl and ortho-substituted aryl derivatives of lactic acid was carried out. Two variants of hydrogen-bonded associates in the gas phase were calculated: non-classical, actually found in the crystals, and simulated classical dimers. The energy advantage of classical dimers and the non-equivalence of diastereotopic electron lone pairs at the carbonyl oxygen atom were shown.
{"title":"Theoretical Study of the Association of Aryl Derivatives of Lactic Acid","authors":"D. Gerasimova, L. V. Frantsuzova, R. Fayzullin, O. Lodochnikova","doi":"10.26907/2542-064x.2023.1.49-57","DOIUrl":"https://doi.org/10.26907/2542-064x.2023.1.49-57","url":null,"abstract":"A theoretical study of the association of phenyl and ortho-substituted aryl derivatives of lactic acid was carried out. Two variants of hydrogen-bonded associates in the gas phase were calculated: non-classical, actually found in the crystals, and simulated classical dimers. The energy advantage of classical dimers and the non-equivalence of diastereotopic electron lone pairs at the carbonyl oxygen atom were shown.","PeriodicalId":23418,"journal":{"name":"Uchenye Zapiski Kazanskogo Universiteta. Seriya Estestvennye Nauki","volume":null,"pages":null},"PeriodicalIF":0.3,"publicationDate":"2023-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"81582274","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
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