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Summary: Most countries have tried to decline fossil fuels dependency by supporting clean energy transition. In light of this, this study investigates the impact of energy security risk (ESR) and geopolitical risk (GPR) on the load capacity factor (LCF) in four fragile countries (Brazil-BRA; India-IND; South Africa-ZAF, Türkiye-TUR). The study applies quantile approaches for the period between 1985/m2 and 2018/m12, which represents the largest amount of accessible data. The results show that (i) at higher quantiles, ESR declines the LCF in IND and ZAF, while it has an increasing impact in BRA and a mixed impact in TUR; (ii) GPR increases the LCF in BRA, ZAF, and TUR at lower and middle quantiles, while GPR decreases ecological quality at higher quantiles in all countries; (iii) ESR and GPR have a causal effect on the LCF across various quantiles; (iv) ESR and GPR are strong predictors of the LCF, but their predictive power varies by quantile and becomes significantly weaker with increasing lags. With these fresh outcomes, the study underlines the significant influence of ESR and GPR in ensuring ecological sustainability across all quantiles and countries. The overall findings of the study emphasize that risks and uncertainties degrade the ecological quality of four fragile countries and that policymakers should turn to clean energy sources in case of an increase in geopolitical and energy risks.

Summary: On the one hand, economies, particularly developing ones, need to grow. On the other hand, climate change is the most pressing issue globally, and nations should take the necessary measures. Such a complex task requires new theoretical and empirical models to capture this complexity and provide new insights. Our study uses a newly developed theoretical framework that involves renewable energy consumption (REC) and total factor productivity (TFP) alongside traditional factors of CO2 emissions. It provides policymakers with border information compared to traditional models, such as the Environmental Kuznets Curve (EKC), being limited to income and population. Advanced panel time series methods are also employed, addressing panel data issues while producing not only pooled but also country-specific results. 20 Renewable Energy Country Attractiveness Index (RECAI) nations are considered in this study. The results show that REC, TFP, and exports reduce CO2 emissions with elasticities of 0.3, 0.4, and 0.3, respectively. Oppositely, income and imports increase emissions with elasticities of 0.8 and 0.3. Additionally, we show that RECAI countries are commonly affected by global and regional factors. Moreover, we find that shocks can create permanent changes in the levels of the factors but only temporary changes in their growth rates. The main policy implication of the findings is that authorities should implement measures boosting TFP and REC. These factors are driven mainly by technological progress, innovation, and efficiency gains. Thus, they can simultaneously reduce emissions while promoting long-run green economic growth, which addresses the complexity mentioned above to some extent.

Summary: Doping effects on the electronic and magnetic properties of Zn1−x(Co,Cr)xO systems are investigated within Local Spin Density Approximation and Hubbard U methods. Based on Density Functional Theory the spin-polarization band structures, density of states for investigated systems are calculated. Systematic analysis of the electronic properties shows that TM-doped ZnO has generated new energy levels in the vicinity of Fermi energy level. From first-principle calculations we obtained Cr-ZnO and Co-ZnO systems are metallic and half-metallic ferromagnetic materials, respectively. The obtained results for Cr-doped ZnO 128- and 192-atom supercell systems show magnetic properties with higher Curie temperature than room temperature. There are large local moments, ∼2.9 and ∼4.2 for Co and Cr dopants, respectively. Magnetic moments are related with two electron defects in the supercell structure and unpaired electrons of transition metal. The ferromagnetic and antiferromagnetic phases and the total energy are obtained for x = 2.08%, 3.125%, 4.16%, 6.25%, 8.3%, 12.5%, and 25% impurity concentrations for doped ZnO.

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.