scholarly journals USE OF RESINOUS SUBSTANCES BY THE EARLY NEOLITHIC POPULATION IN THE FOREST-STEPPE ISHIM AREA

2019 ◽  
pp. 5-14
Author(s):  
V.A. Zakh
Keyword(s):  
Visual Analysis ◽  
Combustion Process ◽  
Resin Acids ◽  
Volatile Components ◽  
Forest Steppe ◽  
Ir Absorption ◽  
Early Neolithic ◽  
Absorption Bands ◽  
Porous Substance ◽  
Coniferous Trees

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.

Nevirapine Pharmaceutical Cocrystal: Design, Development and Formulation

2019 ◽  
Vol 9 (3) ◽  
pp. 240-247
Author(s):  
Prabhakar Panzade ◽  
Priyanka Somani ◽  
Pavan Rathi
Keyword(s):  
Dosage Form ◽  
In Vitro Dissolution ◽  
Soluble Form ◽  
Ir Absorption ◽  
Stoichiometric Ratio ◽  
Design Development ◽  
Formulation Development ◽  
Scanning Calorimetry ◽  
Absorption Bands ◽  
Pharmaceutical Cocrystal

Background and Objective: The top approach to deliver poorly soluble drugs is the use of a highly soluble form. The present study was conducted to enhance the solubility and dissolution of a poorly aqueous soluble drug nevirapine via a pharmaceutical cocrystal. Another objective of the study was to check the potential of the nevirapine cocrystal in the dosage form. Methods: A neat and liquid assisted grinding method was employed to prepare nevirapine cocrystals in a 1:1 and 1:2 stoichiometric ratio of drug:coformer by screening various coformers. The prepared cocrystals were preliminary investigated for melting point and saturation solubility. The selected cocrystal was further confirmed by Infrared Spectroscopy (IR), Differential Scanning Calorimetry (DSC), and Xray Powder Diffraction (XRPD). Further, the cocrystal was subjected to in vitro dissolution study and formulation development. Results: The cocrystal of Nevirapine (NVP) with Para-Amino Benzoic Acid (PABA) coformer prepared by neat grinding in 1:2 ratio exhibited greater solubility. The shifts in IR absorption bands, alterations in DSC thermogram, and distinct XRPD pattern showed the formation of the NVP-PABA cocrystal. Dissolution of NVP-PABA cocrystal enhanced by 38% in 0.1N HCl. Immediate release tablets of NVP-PABA cocrystal exhibited better drug release and less disintegration time. Conclusion: A remarkable increase in the solubility and dissolution of NVP was obtained through the cocrystal with PABA. The cocrystal also showed great potential in the dosage form which may provide future direction for other drugs.

The Peopling of the Baraba Forest-Steppe in the Neolithic: Cranial Evidence

2021 ◽  
Vol 49 (1) ◽  
pp. 133-146
Author(s):  
T. A. Chikisheva ◽  
D. V. Pozdnyakov
Keyword(s):  
Local Population ◽  
Principal Component ◽  
Early Holocene ◽  
Russian Plain ◽  
Northern Eurasia ◽  
Forest Steppe ◽  
Early Neolithic ◽  
Population Continuity ◽  
Lake Systems

On the basis of statistical analysis of craniometric data relating to Mesolithic and Neolithic samples from northern Eurasia, we discuss the peopling of the Baraba forest-steppe in the Early Holocene. This region is represented by samples from Sopka-2/1 (early sixth millennium BC), Protoka (late fifth to early fourth millennia BC), Korchugan (early-mid sixth millennium BC), and Vengerovo-2A (late sixth millennium BC). The results of the principal component analysis are interpreted in the context of debates over the role of autochthonous traditions in the Neolithic. During the Preboreal period (10 ka BP), large parts of the Baraba forest-steppe were flooded by the transgression of lake systems during climatic warming. This may have caused depopulation, lasting for at least a millennium. The Early Holocene people of Baraba were an offshoot of Meso-Neolithic populations of the northwestern Russian Plain. On that basis, the Early Neolithic populations of Baraba were formed. Direct population continuity is traceable only through the Chalcolithic. Since the late sixth millennium BC, however, the local population had incorporated migrants from the Pit-Comb Ware area in the central Russian Plain and, indirectly (via the Neolithic Altai), from the Cis-Baikal area.

scholarly journals SOME ASPECTS OF LOWER AND MIDDLE VOLGA POPULATION INTERACTION IN NEOLITHIC AGE

2014 ◽  
Vol 3 (3) ◽  
pp. 13-18
Author(s):  
Konstantin Mihailovich Andreev
Keyword(s):  
Forest Steppe ◽  
Early Neolithic ◽  
Late Neolithic ◽  
Lower Volga ◽  
Neolithic Age ◽  
Middle Volga ◽  
Population Interaction

The article analyses the problem of different Neolitization origins in specified regions. In early Neolithic Age the contacts had a small coverage. Wide-ranging penetration of Lower Volga pin- scratched pottery ornamentation tradition carriers into forest steppe refers to VI and V centuries BC. It was caused by natural and climatic reasons. Up to the late Neolithic Age the influence was one-way - from south to north.

scholarly journals Early Neolithic of Trans-Urals: the contemporary view on historiographic problems

2019 ◽  
Vol 8 (2) ◽  
pp. 200-208
Author(s):  
Vadim Sergeevich Mosin ◽  
Ekaterina Sergeevna Yakovleva
Keyword(s):  
Material Culture ◽  
Statistical Processing ◽  
Forest Steppe ◽  
Early Neolithic ◽  
Decorative Motifs ◽  
Critical Issues ◽  
Source Study ◽  
Bodies Of Evidence ◽  
Radiocarbon Chronology ◽  
Archaeological Cultures

This paper is devoted to the critical issues of historiography and source study in the early Neolithic of the Trans-Urals. The authors consider basic dated monuments in the context of radiocarbon chronology; analyze the established criteria for identifying archaeological cultures and ceramic traditions and types of this period. Based on statistical processing of the ceramics of the forest-steppe Tobol region settlements: Tashkovo 1, Dolgovskoe 3, Kochegarovo 1, Ust-Suerka 4, the authors distinguish some stadial features in the evolving of the material culture of the early Neolithic in the first and second halves of 6 thousand BC. Attention is paid, firstly, to the co-existence of Koshkino and Kozlovo ancientries within the settlements, and, secondly, to the coincidence of a number of characteristics of Koshkino and Kozlovo material culture regarding the morphology of potteries, ornamentation techniques and basic decorative motifs. Within the framework of a sociocultural approach, it is proposed to consider the bodies of evidence as complexes of two coexisting and interacting traditions within one sociocultural space, understood in the source sense as an archaeological culture, instead of dividing them into two independent lines of development. Besides it is emphasized that the problem of the Neolithization of Trans-Urals, on the basis of the available data, at this time cannot be solved plausible.

scholarly journals Изотопные эффекты в спектрах комплексов с водородными связями. Ангармонические расчеты изотопологов комплекса [F(HF)-=SUB=-2-=/SUB=-]-=SUP=---=/SUP=-

2020 ◽  
Vol 128 (8) ◽  
pp. 1077
Author(s):  
В.П. Булычев ◽  
М.В. Бутурлимова ◽  
К.Г. Тохадзе
Keyword(s):  
Basis Set ◽  
Ir Absorption ◽  
Absorption Bands ◽  
Spectral Parameters ◽  
Basis Set Superposition Error ◽  
Band Frequency ◽  
Normal Vibrations ◽  
K Meson ◽  
Anharmonic Interactions ◽  
Good Agreement

The frequencies and intensities of IR absorption bands of symmetric and asymmetric H-bonded complexes [FL1FL2F]- (L1, L2 = K-meson Ka, proton H, deuton D, and triton T) are calculated. The equilibrium configuration and potential energy and dipole moment surfaces of isotopologues [FL1FL2F]- were calculated by the MP2/6-311++G(3df,3pd) method with the basis set superposition error taken into account. The calculations of spectral parameters with allowance for anharmonic interactions of all vibrations were carried out using the second-order vibrational perturbation theory. Variation of Li and L2 masses in wide regions allowed significant changes in the forms of normal vibrations and values of anharmonic interaction constants upon isotopic substitution to be obtained. The trends in the changes of spectral parameters were determined upon transition from one symmetric isotopologue to another and upon transition from symmetric to asymmetric isotopologues. The D-F stretching band frequency predicted for [FHFDF]- is in good agreement with the experimental value. The assignment of this band was improved.

scholarly journals Local vibrational modes of vacancy-oxygen-related complexes at room temperature

2020 ◽  
Vol 56 (4) ◽  
pp. 480-487
Author(s):  
E. A. Tolkacheva ◽  
V. P. Markevich ◽  
L. I. Murin
Keyword(s):  
Absorption Band ◽  
Room Temperature ◽  
Clear Correlation ◽  
Ir Absorption ◽  
Oxygen Impurity ◽  
Interstitial Oxygen ◽  
Vibrational Modes ◽  
Oxygen Defect ◽  
Absorption Bands ◽  
Local Vibrational Modes

The isotopic content of natural silicon (28Si (92.23 %), 29Si (4.68 %) и 30Si (3.09 %)) affects noticeably the shape of IR absorption bands related to the oxygen impurity atoms. In the present work an attempt is undertaken to determine the positions of local vibrational modes (LVMs), related to quasimolecules 28Si16OS29Si and 28Si16OS30Si (OS – substitutional oxygen atom), for the absorption spectra measured at room temperature. An estimation of the isotopic shifts of corresponding modes is done by fitting the shape of the experimentally measured absorption band related to the vacancy–oxygen center in irradiated Si crystals. The LVM isotope shifts are found to be equal 2,2 ± 0.25 cm–1 for 28Si-16OS29Si and 4,3 ± 0,9 см–1 for 28Si-16OS30Si in relation to the basic band due to 28Si-16OS28Si, and the full width at half maximum of the A-center absorption band (28Si-16OS28Si) is 5,3 ± 0.25 cm–1. By means of infrared absorption spectroscopy a clear correlation between the disappearance of the divacancy (V2) in the temperature range 200–275 ºС and appearance of two absorption bands with their maxima at 825.8 and 839.2 cm–1 in irradiated oxygen-rich Si crystals is found. The band positioned at 825.8 cm–1 is assigned to a divacancy-oxygen defect V2O formed via an interaction of mobile V2 with interstitial oxygen (Oi ) atoms. The 839.2 cm–1 band is much more pronounced in neutron irradiated samples as compared to samples irradiated with electrons. We argue that it is related to a trivacancy–oxygen defect (V3O) formed via an interaction of mobile V3 with Oi atoms.

Magneto-Chemical Properties of Some New Ni and Co Rare-Earth Metal Tungstates

2007 ◽  
Vol 128 ◽  
pp. 207-212 ◽  
Author(s):  
Adam Worsztynowicz ◽  
Slawomir M. Kaczmarek ◽  
Elzbieta Tomaszewicz
Keyword(s):  
Rare Earth ◽  
Rare Earth Metal ◽  
Epr Spectroscopy ◽  
Chemical Properties ◽  
Earth Metal ◽  
Temperature Evolution ◽  
Ir Absorption ◽  
Absorption Bands ◽  
Metal Tungstates

New d-electron and rare-earth metal tungstates (CoRE2W2O10; CoRE4W3O16; Co2RE2W3O14 and NiRE2W2O10) were studied by the IR and EPR spectroscopy methods. The IR absorption bands with their maxima can be assigned to the symmetric and asymmetric stretching modes of W-O bonds in the joint of WO6 octahedra and also to the oxygen double WOOW bridge bonds. The wide, unstructured EPR powder spectra of these compounds and their temperature evolution have been analyzed and interpreted.

Method for determining the formation constants of intermolecular H-bonding from IR spectroscopy data

2021 ◽  
pp. 55-58
Author(s):  
N.U. Mulloev ◽  
◽  
N.L. Lavrik ◽  
J.O. Yusypova ◽  
N.A. Majidov ◽  
...  
Keyword(s):  
Optical Density ◽  
Formation Constants ◽  
Butyl Alcohol ◽  
Proton Donor ◽  
Proton Acceptor ◽  
Ir Absorption ◽  
Visible Spectroscopy ◽  
Absorption Bands ◽  
Intermolecular Hydrogen Bonds ◽  
Uv Visible

An experimental method is proposed for determining the efficiency of the formation of intermolecular hydrogen bonds by determining the formation constant of the H-complex (K). The essence of the experiment to determine the value of K is that for one initial concentration of the proton donor, it is necessary to register the change in the optical density at the absorption wavelength of the monomers and the change in the optical density of the complexes of IR absorption bands at two concentrations of the proton acceptor. This approach was tested on the example of the interaction of butyl alcohol (proton donor) with 4-chloromethyl-1.3-dioxolane (proton acceptor). The obtained value of the equilibrium constant was 72.2 M-1. It is concluded that the proposed method for determining the value of K can be used not only in IR, but also in UV-visible spectroscopy.

IR spectra of powder hematite: effects of particle size and shape

Clay Minerals ◽  
1981 ◽  
Vol 16 (4) ◽  
pp. 375-382 ◽  
Author(s):  
Jose L. Rendon ◽  
Carlos J. Serna
Keyword(s):  
Particle Size ◽  
Ir Spectra ◽  
Ir Absorption ◽  
Surface Mode ◽  
Absorption Bands ◽  
Size And Shape ◽  
Ir Absorption Spectra ◽  
Theoretical Predictions ◽  
Particle Size And Shape ◽  
Average Size

AbstractHematites obtained by heating goethite gave different IR absorption spectra depending on the temperature of formation. Hematites formed between 250–600°C consisted of lath-like crystals (average size 0.4 ×0.08 µm) and showed, in accordance with theoretical predictions, very similar IR spectra whose absorption bands could all be assigned to surface mode vibrations. However, significantly different IR spectra were given by hematites formed between 700–950°C, the differences being correlated with variations in the size and shape of the particles. Differences observed in the IR spectra of powder hematite do not therefore justify new names for the mineral, as have been proposed in the literature.

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