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Summary: A set of self-consistent thermodynamic parameters of the GeTe-rich germanium-bismuth tellurides were determined using an electromotive force (EMF) method with a glycerol electrolyte in a temperature range from 300 to 450 K. The solid-phase equilibrium diagram of the GeTe-Bi2Te3-Te system at 400 K was constructed using X-ray diffraction (XRD) and scanning electron miscroscope (SEM) techniques of synthesized electrode alloys, as well as available literature data. It is found that all telluride phases in GeTe-Bi2Te3 pseudo-binary section have a tie-line connection with elemental tellurium. The relative partial thermodynamic functions of GeTe in alloys were calculated using data from EMF measurements of concentration cells relative to the GeTe electrode. These findings together with the corresponding thermodynamic functions of GeTe and Bi2Te3 were used to calculate the relative partial molar functions of germanium in alloys, and also the standard thermodynamic functions of formation and standard entropies of the ternary compounds, namely Ge2Bi2Te5, Ge3Bi2Te6 and Ge4Bi2Te7.

Summary: The present study aimed to investigate the presence of asymmetric stochastic volatility and leverage effects within the Nasdaq-100 index. This index is widely regarded as an important indicator for investors. We focused on the nine leading stocks within the index, which are highly popular and hold significant weight in the investment world. These stocks are Netflix, PayPal, Google, Intel, Microsoft, Amazon, Tesla, Apple, and Meta. The study covered the period between 3 January 2017 and 30 January 2023, and we employed the EViews and WinBUGS applications to conduct the analysis. We began by calculating the logarithmic difference to obtain the return series. We then performed a sample test with 100,000 iterations, excluding the first 10,000 samples to eliminate the initial bias of the coefficients. This left us with 90,000 samples for analysis. Using the results of the asymmetric stochastic volatility model, we evaluated both the Nasdaq-100 index as a whole and the volatility persistence, predictability, and correlation levels of individual stocks. This allowed us to evaluate the ability of individual stocks to represent the characteristics of the Nasdaq-100 index. Our findings revealed a dense clustering of volatility, both for the Nasdaq-100 index and the nine individual stocks. We observed that this volatility is continuous but has a predictable impact on variability. Moreover, apart from Intel, all the stocks in the model exhibited both leverage effects and the presence of asymmetric relationships, as did the Nasdaq-100 index. Overall, our results show that the characteristics of stocks in the model are like the volatility characteristic of the Nasdaq-100 index and can represent it.

Summary: Utilizing ligands based on pyrazole synthesized some transition metal complexes. Selected salts such as Co(CH3COO)2·4H2O, Ni(CH3COO)2·4H2O (in the presence of triethylamine), Cu(CH3COO)2·H2O (in the presence of triethylamine) and CuCl2·2H2O reacted with the ligand (E)-1-(amino(1H-pyrazol-1-yl) methylene) guanidinium chloride in methanol as a solvent. Obtained novel metal complexes characterized using different analyses such as infrared spectroscopy, electrospray ionization mass spectrometry, single-crystal X-ray diffraction, and elemental analysis. Additionally, a novel series of complexes (2a-d) were investigated for their ability to inhibit enzymes. They exhibited highly potent inhibition effect on human carbonic anhydrase I and II (hCA I and II) and α-glycosidase (Ki values are in the range of 7.14 ± 1.97 to 29.34 ± 3.18 µM, 9.86 ± 2.46 to 32.47 ± 4.82 µM, and 2.08 ± 0.11 to 4.03 ± 0.30 µM for hCA I, hCA II, and α-glycosidase, respectively). Indeed, insulin and oral antidiabetic medications are the two mainstays of clinical diabetes treatment. To learn more about the potential of pyrazole-based metal complexes of Cu, Ni, and Co and how successfully they can inhibit hCA I, hCA II, and α-Gly enzymes, molecular docking applications were performed.

Summary: A model of a single-server queuing-inventory system (QIS) with a limited waiting buffer for consumer customers (c-customers) and catastrophes has been developed. When a catastrophe occurs, all items in the system’s warehouse are destroyed, but c-customers in the system are still waiting for replenishment. In addition to c-customers, negative customers (n-customers) are also taken into account, each of which displaces one c-customer (if any). The policy (s, S) is used to replenish stocks. If, when a customer enters, the system warehouse is empty, then, according to Bernoulli’s trials, this customer either leaves the system without goods or joins the buffer. The mathematical model of the investigated QIS is constructed in the form of a continuous-time Markov chain (CTMC). Both exact and approximate methods for calculating the steady-state probabilities of constructed CTMCs are proposed and closed-form expressions are obtained for calculating the performance measures. Numerical evaluations are presented, demonstrating the high accuracy of the developed approximate formulas, as well as the behavior of performance measures depending on the input parameters. In addition, an optimization problem is solved to obtain the optimal value of the reorder point to minimize the expected total cost.

Summary: The essay focuses on the problems that hindered the ghazal genre from developing and how the poet kept the tradition alive in Azerbaijani literature at the start of the 20th century. We used Aliagha Vahid's literary creativity for our project since he lived through this period in Azerbaijan, experienced all of its hardships, and demonstrated the genre's potential by creating poetic imagery of the time in his ghazals. He is an Azerbaijani poet who is revered in the Turkic community as Fuzuli's successor and is credited with saving the ghazal genre in Azerbaijani literature. Analyzing his lyrics provided excellent possibilities to examine the influential factors on all of the Azerbaijani literature at the time. In the study, his creation of new kinds of ghazals with social and political issues while retaining the characteristics of the traditional ghazal genre was investigated. With him, the genre in Azerbaijani literature underwent a new phase. The attempt to eradicate the ghazal from the Azerbaijani literature which has a history of centuries-long history did not succeed as a result of mostly Aliagha Vahid's serious efforts. For this purpose, the poet's historical milieu, the challenges of the repression, his satirical ghazals with a sociopolitical theme, the thematic details of his lyrics, and other issues have been involved in the investigation.

Summary: The electrical and photoelectric properties of anisotype n-Si−p-GaSe heterojunctions obtained as a result of the deposition of a GaSe thin layer on a cold n-Si single crystal substrate by the thermal evaporation method were studied. It was determined that the height of the potential barrier in thermal annealing structures at T = 200°C during t = 3 hours occurs due to the decrease in the density of states of local levels located near the Fermi level in the amorphous layer. The mechanism of photosensitivity in an isotype heterostructures was analyzed and it was found that the photosensitivity of the heterojunction increases as a result of a decrease in the surface density of state at the contact boundary of the components, by thermal means. The spectral distribution of the quantum efficiency in the n-Si – p-GaSe heterojunction was studied and their perspective was determined.

Summary: The radiation oxidation of Be in water at room temperature in the absorbed dose range Dγ = 0.5…180 kGy was studied by radiothermoluminescence (RTL), infrared reflection-adsorption spectroscopy (IRRAS), and electrical conductivity. The participation and role of surface relaxing intermediate-active particles in the dynamics of changes in the oxidation process are considered. Using the RTL method, the role of surface oxygen hole centers generated by γ-irradiation and chemisorbed oxygen in the formation of nanooxide films was experimentally established. The formation of nanooxide films on the surface of Be in water was traced in the IR reflection spectra. The kinetics of radiation oxidation of beryllium has been studied and its radiation passivation has been established. According to the logarithmic dose dependence of the surface resistivity Be, two stages of the oxidation process were revealed. It is shown that the formation of nano oxide films leads to a decrease in the surface electrical conductivity of beryllium by 2 orders of magnitude and an increase in the thickness of oxide films by 1.6 times.

Summary: The studied thermoelectric materials based on Bi2Te3 attracted researches attention, due to thermoelectric properties allow direct conversion between thermal and electrical energy. In this work, we examined the (0001) surfaces for investigated АV 2BVI 3 crystals before and after irradiation implementing the AFM method. We have been studied the fractality of formed nano-objects and resulting in the formation of nanoislands on different scales.

Summary: Azerbaijan is an exporter country of natural resources (oil). Since the main power of modern economy including the future economic progress is human factor, human capital, its knowledge, ability of using technology, transferring oil capital into human capital is a driving factor. That’s why researching the influence of the main indicators of education and state budget allocations for it is a topical issue. The article has researched the relationship of state budget allocation and the main indicators of education and science during 21 years (1996−2017) in the Restate of Azerbaijan. Auto Regressive Distributed Lags has been used as a research model. Besides, stationary tests of variables (Augmented Dickey Fuller, Phillips-Perron, Kwiatkowski-Phillips-Schmidt-Shin) and Pairwise Granger Causality Tests were used. Model stability was studied. Eviews_9 software program was applied for making graphics and calculations. Research has examined that there is a positive dependency between state budget allocation and the main indicators of education. We recommend that state budget allocation for science and education can be increased and used as the intended purpose.