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The IR spectra of CDF3 in the solid Ar and N2 matrices were measured and analyzed in the region of the Fermi polyads 2ν4/ν1/2ν2/ν4 + ν5, complicated by a close Fermi resonance ν4/ν3 + ν6. The symmetry lifting effect, observed in the N2 matrix, was found helpful for an accurate assignment of the individual components. The anharmonic calculation of the potential energy surface and the dipole moment function was performed on the MP2/aug-cc-pVTZ level. The unperturbed values of vibrational eigenstates were determined in the region of ν1 (CD stretching vibration) in both matrices. The experimental findings and theoretical analysis are in good agreement. [ABSTRACT FROM AUTHOR]

Research findings can offer data and a theoretical framework for a quantitative examination of the bentonite dehydration mechanism. The reasons for changes in pore’ water under the influence of gamma rays in vacuum and in the presence of oxygen was discussed using TGA and DTA, FT-IR spectroscopy. It was revealed that dehydration and pore characteristics are mutually dependent. A question about the associated evolution of dehydration pore‘s water in nanostructured sodium – bentonite clay under the influence of ionizing rays with and without oxygen has been comparatively studied. The article is devoted to a discussion of how ionizing radiation, passing through nanoclays, produces, or rather begins to produce, chemical effects. It was used Infrared spectroscopy as the method for determining structural responses of natural clay from the Alpoid deposit in the Republic of Azerbaijan, to gamma rays exposure. It was found that under influence of ionizing rays in vacuum obtained hydrogen peroxide. It is of great interest for the study of the dehydration reaction mechanism and its role in formation of H2 under gamma irradiation. [ABSTRACT FROM AUTHOR]

In the present investigation, pure and different concentrations (2%, 4%, 6%, 10%) of Ag-doped Co3O4 nanoparticles have been synthesized by the sonochemical method and subsequent calcination at different high temperatures. Structural, optical, morphological properties and elemental composition of synthesized nanoparticles have been characterized using X-ray diffraction, UV–visible spectroscopy, Fourier transform infrared spectroscopy, Raman spectroscopy, transmission electron microscopy and energy-dispersive X-ray spectroscopy. According to X-ray diffraction results, no peaks related to silver or silver oxide were observed in the diffractograms of doped samples. Blue shift was observed in the absorption curve of Ag-doped Co3O4 nanoparticles compared to undoped Co3O4 nanoparticles. From transmission electron microscopy measurements, 2%, 4% and 6% Ag-doped Co3O4 nanoparticles thermal annealed at 500 °C exhibit sphere-like and irregularly structured morphology, while 10% Ag-doped Co3O4 nanoparticles have a rhombohedral-like, hexagonal and spherical morphology. The dielectric constant value (ɛʹ) was found to decrease with increasing frequency and it can be explained by Maxwell–Wagner model. The value of the dielectric constant increased with increasing of temperature from 25 to 100 °C and the highest value was observed for Ag0.1Co2.9O4/PVA sample at 100 °C temperature. [ABSTRACT FROM AUTHOR]

Gamma-irradiated samples of the polyethylene/CdS+ZnS (PE/CdS+ZnS) composite were studied by electron paramagnet resonance and Fourier infrared spectroscopy methods. Based on the electron paramagnet resonance spectra, the nature of the induced paramagnetic radiation defects and their quantitative dependence on the absorbed dose of gamma radiation are identified. It has been established that the studied polymer composites have a higher radiation resistance in the range of absorption doses D =30-100 kGy compared to pure polymer. The obtained results were confirmed by Fourier infrared spectroscopy, and it was shown that the observed changes are associated with a change in the supramolecular structure of PE/CdS+ZnS irradiated with-quanta. [ABSTRACT FROM AUTHOR]

Introducing of the methyl substituent into the C-C(H)=N moiety of the Schiff bases alters the tautomeric equilibrium in favor of the proton transfer forms in comparison with Schif bases deprived of such substituent and related Mannich bases is demonstrated. Accordingly, a scheme of proton transfer equilibria specific for Schiff bases is proposed, which is in agreement with numerous structural evidences.

The sequences of Fermi resonances νs ≈ 2νb in the IR spectrum of a fluoroform solution (CHF3) in liquefied krypton have been studied. Here, νs is the CH-stretching vibration and νb is the bending vibration. It has been shown that it is necessary to use an extended set of spectroscopic parameters for the correct description of resonant multiplets at a high degree of vibrational excitation. Among other factors, it is necessary to consider the dependence of the anharmonic interaction constant αsbb on the vibrational quantum numbers. The conclusions are generalized for the arbitrary case of the CH-chromophore CHX3. [ABSTRACT FROM AUTHOR]

The sequences of Fermi resonances νs ≈ 2νb in the IR spectrum of a fluoroform solution (CHF3) in liquefied krypton have been studied. Here, νs is the CH-stretching vibration and νb is the bending vibration. It has been shown that it is necessary to use an extended set of spectroscopic parameters for the correct description of resonant multiplets at a high degree of vibrational excitation. Among other factors, it is necessary to consider the dependence of the anharmonic interaction constant αsbb on the vibrational quantum numbers. The conclusions are generalized for the arbitrary case of the CH-chromophore CHX3. [ABSTRACT FROM AUTHOR]

Using Fourier transform IR spectroscopy, the radiation–thermal decomposition of water in the nano-ZrO2 + nano-SiO2 + H2O system in the temperature range of T = 373–673 K under the influence of γ-rays was studied. It is shown that water adsorption in zirconium and silicon nanooxides occurs by the molecular and dissociative mechanisms. Intermediate-active products of the radiation-heterogeneous decomposition of water—zirconium and silicon hydrides, hydroxyl groups—have been registered. The values of the velocities and radiation–chemical yields of molecular hydrogen during the radiolysis of water in the presence of nano-ZrO2 + nano-SiO2 mixtures were determined. It was revealed that the values of the velocities and radiation–chemical yields decrease on going from nano-ZrO2 to nano-SiO2. The stimulating role of radiation in the radiation–thermal decomposition of water in the temperature range of T = 373–673 K is shown. [ABSTRACT FROM AUTHOR]

Using the method of IR Fourier-transform spectroscopy, the radiation decomposition of water in the nano-ZrO2 + nano-SiO2 + H2O system at room temperature (T = 300 K) under the influence of γ-quanta is studied. It is shown that the adsorption of water by the zirconium and silicon nanooxides proceeds by the molecular and dissociative mechanisms. The following intermediate active products of the radiation-heterogeneous decomposition of water are registered: Zr and Si hydrides, and hydroxyl OH groups. It is shown that a change in the ratio of the ZrO2 and SiO2 nanopowders gives rise to a change in the surface profile and in the radiation-chemical yield of molecular hydrogen. [ABSTRACT FROM AUTHOR]

The radiation decomposition of water in a nano-ZrO2 + nano-SiO2 + H2O system at 300 K by the action of gamma radiation has been studied by Fourier transform IR spectroscopy. Water adsorption in the zirconium and silicon nanooxides is attributed to molecular and dissociative mechanisms. Active intermediates in this radiation-induced heterogeneous decomposition of water were detected including zirconium and silicon hydrides and hydroxyl groups. Variation in the ratio of ZrO2 and SiO2 nanopowders was shown to lead to change in their radiation catalytic activity compared to initial ZrO2. [ABSTRACT FROM AUTHOR]

The FTIR spectra of chloroform (Cl3CH) in mixtures with various electron donors (B = CH3CCH, HCCH, NCCD3, ClCD3and CO) have been studied in liquefied Kr. Spectroscopic evidence of weak H-bond formation has been found. The relative stability of some complexes has been evaluated from temperature studies of integrated intensities of vibrational bands attributed to monomer and complex species. A weak red shift of the stretching vibration of chloroform involved in H-bonding with CH3CCH and HCCH having π-electron area was observed. However, in the case of interactions with NCCD3and CO, a weak blue shift was detected. In most of the cases, a noticeable increase in the integrated intensity of the CH stretching band was found. Ab initioMP2/6-311++G(2d,2p) a prioricounterpoise corrected calculations have been performed for a series of Cl3CH and B. Stationary points at the potential energy surface were examined and the structures related to the real minima have been found. The calculations reproduce the majority of experimental results. It has been found that the commonly used correlation between the frequency shift of the CH stretching vibration of the proton donor subunit and the change in CH bond length can fail in the case of the complexes characterized by a weak frequency shift effect. [ABSTRACT FROM AUTHOR]

The IR absorption spectrum of mixtures of CH[sub 4] with Kr in the range 800-6000 cm[sup -1] is studied in the region of the gas-liquid and liquid-crystal phase transitions. It is found that, as the system density increases, the ratio of the ν[sub 4] band intensity to that of the ν[sub 3] band becomes larger and the measured values of the second spectral moment of the ν[sub 4] band become smaller than the corresponding calculated values. The quantum counterpart of the generalized J-diffusion model was used to describe the shape of the ν[sub 3] and ν[sub 4] bands, and the rotational relaxation times of CH[sub 4] in solutions were obtained. It was shown that, as the density increases, a broad 1470-cm[sup -1] band appears in the region of the "forbidden" (induced by a Coriolis interaction) ν[sub 2] band (ν[sub Q] = 1535 cm[sup -1]) detected in a low-density gas. The intensity of this band is appreciably higher than that of the ν[sub 2] band. [ABSTRACT FROM AUTHOR]

We investigate the IR spectra of solutions of R-21,-22,-116, and R-218 in liquid argon at 90K. The frequencies, half-widths, and absolute integral intensities of all of the absorption bands recorded are obtained and interpreted. [ABSTRACT FROM AUTHOR]

The samples obtained by the Hammer method and then doped with 5, 10 and 15 percent gadolinium were studied by the EPR analysis method. The conducted studies were carried out at room temperature. Depending on the degree of addition of gadolinium during the studies an increase in the intensity of the signal and a decrease in the intensity of free radicals were observed. So that, when the amount of gadolinium reaches 15%, the signal of free radicals disappears. The reason for this is that the Gd ion forms a single homogeneous system with the formation of strong bonds between the surface of the graphene oxide sample. In addition, it can be noted that unpaired electrons in the form of free radicals, which are stabilized in the carbon rings in the crystal structure of graphene oxide, cause this connection. [ABSTRACT FROM AUTHOR]

In the present investigation, Cu x Co 3- x O 4 ( x = 0, 0.02, 0.04, 0.06, 0.1) nanoparticles have been synthesized by the sonochemical method and subsequent calcination at high temperature. The synthesized nanoparticles were further characterized using X-ray diffraction, UV-vis spectroscopy, FT-IR spectroscopy, Raman spectroscopy, transmission electron microscopy and energy-dispersive X-ray spectroscopy. The analysis results showed that nanoparticle size, band gap and photocatalytic activity of Cu x Co 3- x O 4 compounds change by altering the Cu doping content. According to the XRD study, no impurity peaks associated with copper or copper oxide phases were observed in the diffractograms of doped samples. The highest degradation of methylene blue dye under visible light was observed in the presence of Cu 0.02 Co 2.98 O 4 nanoparticles and found to be 87.51% after 330 minutes. This value increased with increasing the amount of photocatalyst and with decreasing dye concentration., Competing Interests: There are no conflicts to declare., (This journal is © The Royal Society of Chemistry.)

The IR spectra of CDF3 in the solid Ar and N2 matrices were measured and analyzed in the region of the Fermi polyads 2ν4/ν1/2ν2/ν4 + ν5, complicated by a close Fermi resonance ν4/ν3 + ν6. The symmetry lifting effect, observed in the N2 matrix, was found helpful for an accurate assignment of the individual components. The anharmonic calculation of the potential energy surface and the dipole moment function was performed on the MP2/aug-cc-pVTZ level. The unperturbed values of vibrational eigenstates were determined in the region of ν1 (CD stretching vibration) in both matrices. The experimental findings and theoretical analysis are in good agreement., (© 2023 Author(s). Published under an exclusive license by AIP Publishing.)

Treatment of infected mesh implants of anterior abdominal wall is a complex problem in the absence of a unified approach. Traditional method involving surgical debridement of the site of infection with removal of mesh implant is associated with many risks and potential complications. This review is devoted to peculiarities of paraprosthetic infection, possible preserving the implant and methods of treating wound infection avoiding removal of endoprosthesis. Requirements for preservation of mesh implant and key role of vacuum therapy are emphasized.

Objective: To improve the results of diagnosis and treatment of patients with abdominal injuries through a wider introduction of laparoscopic methods., Material and Methods: We analyzed 3556 patients with concomitant abdominal injuries. All patients had damage to several organs and systems. Laparoscopy was performed in 1962 patients, laparotomy without previous laparoscopy - in 1594 patients., Results: Laparoscopy found no abdominal injuries in 25.7% of patients, other 13.7% of patients required no surgery and follow-up was indicated. In 60.7% of patients, injuries required surgical correction. Among these lesions, 26.6% of injuries were successfully eliminated using laparoscopic approach. In some cases, more than one injury was corrected. Indications for laparotomy were overestimated in 30.2% of patients who underwent open surgery without previous laparoscopy., Conclusion: There is a tendency to decrease in the number of open and laparoscopic procedures for concomitant abdominal trauma over time that is associated with widespread introduction of modern diagnostic methods and accumulation of experience. Laparoscopy should be preferred for diagnosis of abdominal injuries in patients with concomitant trauma and no contraindications. This approach diagnoses no injuries or their mild nature in 39.3% of cases. Moreover, laparoscopy effectively eliminates certain lesions in 26.6% of cases.

Introduction: Most seizures during pregnancy occur in women who already have epilepsy. Rarely, some women may have their first seizure during pregnancy. The purpose of this study was to investigate the clinical features and pregnancy outcomes in women with new-onset epilepsy during pregnancy., Methods: 112 pregnant women with epilepsy were prospectively evaluated at the Education - Therapeutic Clinic of the Azerbaijan Medical University, in the neurological and maternity departments of the Clinical Medical Center in Baku over a six-year period. Women were regularly followed by a neurologist and obstetrician till the end of pregnancy. To determine the recurrence of seizures during the pregnancy and after delivery, the women were followed up at least once per three months for a one year period after delivery. Delivery and perinatal outcomes were compared with those of 277 healthy women in the control group (without epilepsy and without registering chronic diseases)., Results: Of the 112 pregnant women with epilepsy, 12 (10.7%) had their first seizures during the pregnancy: 6 in the 1 st , 4 in the 2 nd , 2 in the 3 rd trimester. Women with new-onset epilepsy had increased risk of cesarean section and perinatal hypoxia in offspring, compared with controls (Odds ratio [OR]: 13.57; 95% confidence interval (CI):2.86-64.31 and OR: 3.61; 95 % CI: 1.06-12.27, respectively). The risks of cesarean section and perinatal hypoxia were not increased in women with new-onset epilepsy compared to women with epilepsy before pregnancy (OR 2.64; 95 % CI 0.54-12.93 and OR 2.18, 95% CI 0.61-7.76, respectively)., Conclusion: In our cohort, women with new-onset epilepsy may have an increased risk of delivery by cesarean section and perinatal hypoxia compared to pregnant controls. The risks were not increased compared to women with epilepsy before pregnancy. Neonatal hypoxia was associated with delivery by cesarean section., (Copyright © 2020 British Epilepsy Association. Published by Elsevier Ltd. All rights reserved.)

Purpose: Epilepsy is a common neurological disorder that may complicate reproductive health. Our aim in this study was to provide prospective ascertainment of obstetric and neonatal outcomes in women with epilepsy and investigate whether the risk of pregnancy, delivery, and neonatal complications differed between women with epilepsy and women without epilepsy., Methods: Pregnant women with epilepsy and women without epilepsy (control group) were prospectively evaluated during the years 2013-2018. They were regularly followed by a neurologist and obstetrician until the end of pregnancy., Results: Delivery and perinatal outcomes were compared between 112 women diagnosed with epilepsy and 277 women without epilepsy. Epilepsy was a significant risk factor for preterm delivery, cesarean section, fetal hypoxia, and Apgar score ≤ 7 at 5 min in offspring (odds ratio (OR) = 2.83, 95% confidence interval (CI) 1.03-7.76; OR = 5.61, 95% CI 3.44-9.14; OR = 1.81, 95% CI 1.08-3.04; OR = 8.12, 95% CI 4.04-16.35, respectively). Seizures during pregnancy had influence on the preference of cesarean section as a mode of delivery (ОR = 3.39; 95% CI 1.40-8.17). The rate of perinatal hypoxia was significantly higher in children born by cesarean section (ОR = 2.84; 95% CI 1.04-7.76). There was no significant difference between women with epilepsy and controls in malformation rate., Conclusions: Women with epilepsy had an increased risk of pregnancy and delivery complications. Cesarean section was associated with an increased risk of complications in offspring.

Objective: To study the features of surgical anatomy of intrahepatic segments of right portal vein., Material and Methods: The results of 260 histological examinations including sectional (n=60) and clinical (n=200) surveys were analyzed. Anatomical analysis implied assessment of organometric characteristics including liver weight, length, width and thickness of right and left lobes, division angles of portal vein, the number of branches, length and diameter of the vessels. Clinical examination was based on analysis of splenoportograms and X-ray direct portal venograms. Patients were divided into three groups according to their body type (dolichomorphic, mesomorphic, brachymorphic)., Results: Anatomical and clinical surveys confirmed the differences in metric characteristics of portal vascular system depending on the body type. There was medial angulation of the median fissure under 70-85º (78.0±3.4°) in dolichomorphic and mesomorphic patients. Right angle between the median fissure and lower liver surface was observed in brachymorphic subjects. Portal vein division into the branches of the first order to the right of the median fissure was found in 49 cases. Median or left-sided division was noted in other cases. In most cases (n=219), right portal vein dichotomously divided into the right paramedian and right lateral branches. Portal trifurcation was detected in 2.3% of cases, medial translocation of the right paramedian branch - in 1.1% of cases., Conclusion: Right liver lobe surgery may be associated with certain technical difficulties due to variable anatomy of the right portal vein. Anatomical and atypical liver resections should be preceded by preoperative identification of individual anatomical variations of the main liver vessels. Contrast-enhanced computed tomography is optimal method for this purpose.

The IR spectra of isoflurane + dimethyl ether mixtures dissolved in liquid Kr are registered at T ~118-160 K. The results obtained at a wide range of relative concentrations suggest the formation of complexes stabilized by non-covalent interactions of H-bond type. Large excess of DME and low temperature favor trimer formation stabilized by interactions between two DME moieties and both CH groups of isoflurane predominantly. Estimations based on ab initio calculation of spectroscopic and thermodynamic parameters confirm the experimental findings., (Copyright © 2019 Elsevier B.V. All rights reserved.)