In recent years, due to increasing energy requirements and special attention to the issue of carbon, hydrogen fuel has become an efficient alternative to energy carriers. The aim of this article is to present and investigate of a novel solar-driven hydrogen generation process. The introduced hybrid energy system (HES) is comprised of a solid oxide electrolyzer (SOE), solar photovoltaic (SPV) modules, and solar dish collectors (SDCs). Further, since one of the most attractive utilizations of hydrogen fuel is as a fuel cell's fuel, the present HES suggests that hydrogen fuel be injected into molten carbonate fuel cell (MCFC) to convert it into useful electrical and thermal energies. Finally, the electrical energy obtained from HES is stored via a relatively new hybrid storage system (i.e., pumped hydro and compressed air (PHCA) storage system) for peak and night hours. Therefore, the considered HES in the present study can generate electrical and thermal power, hydrogen fuel and oxygen gas, and store electricity. Although some publications on solar-driven hydrogen generation process are available, there is no study on proposed HES of the present article that considers both energy production and storage. In other words, the components embedded in the proposed HES are developed in such a way that the relationships between them are novel. According to the numerical simulation, it was found that the electrical energy production rate and electrical efficiency of HES are almost 183.1 kWh/day and 33.6 %, respectively. HES can also produce approximately 3.9 kg of hydrogen fuel per day. Moreover, the storage system size for storing the electricity yielded from the considered HES should be nearly 29.9 m³ (at n = 1.2). Also, the storage efficiency of the energy cycle is 59.1 %. The considered process is investigated under different effective parameters in order to identify their effectiveness.
In this work, the dynamical behaviors of the Jimbo-Miwa equation that describes certain interesting (3 + 1)-dimensional waves in physics but does not pass any of the conventional integrability tests are studied. One-, two-, and three-M-lump waves are constructed successfully. Interactions between one-M-lump and one-soliton wave, between one-M-lump and two-soliton wave as well as between two-M-lump and one-soliton solution are reported. Also, complex multi-soliton, solutions are offered. The simplified Hirota's method and a long-wave method are used to construct these types of solutions. The velocity of a one-M-lump wave is studied. Straight Lines of travel for M-lump waves are also reported. To our knowledge, all gained solutions in this research paper are novel and not reported beforehand. Moreover, the gained solutions are presented graphically in three dimensions to better understand the physical phenomena of the suggested equation.
Contact between languages has been going on for centuries. Languages are not immune to linguistic exchanges. The lexicons of these languages have been greatly influenced by the various languages with which they have come into contact. The exchanges of these languages are under the influence of political, social, economic, touristic and cultural relations, with countries having one or more different languages. And lexical units from other languages are called in French LOANS (des EMPRUNTS). The lexicon continues to grow, mimicking the development of the whole society. The causes of borrowing are linked to different sociocultural and sociolinguistic conditions. Some borrowings are used in technical fields, such as sport, music, and cooking, to designate a foreign word that does not exist in the language system of the so-called target language, by copying and pasting these words, such as football, crescendo, and hamburger. That is to say, we borrow a word from a source language to fill the gap in the target language. Other borrowings come from the globalization of languages, such as the word weekend which already exists in French in the form end of week. French, like almost all languages in the world, has borrowed lexical units from other languages. The issue of borrowings that interests us here is that of contact between French and Kurdish, and French and Arabic.
This work aims to detect the associations of C-peptide and the homeostasis model assessment of beta-cells function (HOMA2-B%) with inflammatory biomarkers in pregnant-women in comparison with non-pregnant women. Sera of 28 normal pregnant women at late pregnancy versus 27 matched age non-pregnant women (control), were used to estimate C-peptide, triiodothyronine (T3), and thyroxin (T4) by Enzyme-linked-immunosorbent assay (ELISA), fasting blood sugar (FBS) by automatic analyzer Biolis 24i, hematology-tests by hematology analyzer and the calculation of HOMA2-B% and homeostasis model assessment of insulin sensitivity (HOMA2-S%) by using C-peptide values instead of insulin. The comparisons, correlations, regression analysis tests were performed by the software of statistical package for the social sciences (SPSS). In pregnant women group, HOMA2-B%, T3, T4, white blood cell (WBC), MID cells, granulocytes (GRAN) increased significantly (p-values˂0.05), while C-peptide level raised about 11% compared to control. Lymphocytes, red blood cells (RBC), platelets (PLT) and hemoglobin (HGB) decreased significantly (p-values˂0.05). Lymphocytes predicted both HOMA2-B% and C-peptide level during pregnancy (R2 =0.516, p ˂0.0004; R2=0.31, p ˂0.009 respectively). Prediction of HOMA2-B% and C-peptide levels by lymphocytes account clarifies that the adaptation in beta-cells might be a part of the defense system mechanism of the body against oxidative stress, and this highlights new insight on the proliferation of beta-cells during pregnancy and insulin sensitivity.
This study investigates the Hamiltonian amplitude equation by using the generalized exponential rational function method. As a result, a variety of soliton solutions have been established with different wave structures such as optical exponential, dark, singular, periodic, periodic-singular, and hyperbolic solutions. 2D and 3D graphics of certain acquired solutions are drawn with the help of computer program. By picking appropriate values for the free parameters in the obtained solutions, the physical phenomena for these obtained solutions are graphically studied and depicted.
In this study, we investigate a system of equations based on ion sound and Langmuir waves equations using a generalized exponential rational function, and a new technique named as a modified generalized exponential rational function method. The concept of the new approach is to modify the generalized exponential rational function method. To evaluate the efficiency of the new scheme, we applied the two methods to the given system of equations, and we chose the same values of the parameters in all families, as well as we presented the difference between the solutions in the result and the discussion section. One might easily conclude that the new approach is quite effective and successful in seeking the exact solutions of the nonlinear differential equations. As a result, we have identified a variety of new families of exact travel wave solutions. In addition, we plotted 2D, 3D and contour graphs for some reported solutions by choosing the suitable parameters values.
Heart Disease (HD) is often regarded as one of the deadliest human diseases. Therefore, early prediction of HD risks is crucial for prevention and treatment. Unfortunately, current clinical procedures for diagnosing HD are costly and often require an expert level of intervention. In response to this issue, researchers have recently developed various intelligent systems for the automated diagnosis of HD. Among the developed approaches, those based on artificial neural networks (ANNs) have gained more popularity due to their promising prediction results. However, to the authors’ knowledge, no research has attempted to exploit ANNs for feature extraction. Hence, research into bridging this gap is worthwhile for more excellent predictions. Motivated by this fact, this research proposes a new approach for HD prediction, utilizing a pre-trained Deep Neural Network (DNN) for feature extraction, Principal Component Analysis (PCA) for dimensionality reduction, and Logistic Regression (LR) for prediction. Cleveland, a publicly accessible HD dataset, was used to investigate the efficacy of the proposed approach (DNN + PCA + LR). Experimental results revealed that the proposed approach performs well on both the training and testing data, with accuracy rates of 91.79% and 93.33%, respectively. Furthermore, the proposed approach exhibited better performance when compared with the state-of-the-art approaches under most of the evaluation metrics used.
Extensive work on InAs quantum dots grown on GaAs substrates has been reported in the literature. However, research in the use of different substrate materials such as silicon to achieve an ideal and full integration of photonic and electronic systems is still a challenge. In this work we have investigated the effect of the substrate material (Si and GaAs) and strain reducing layer on the optical properties of InAs quantum dots for possible applications in laser devices grown by Molecular Beam Epitaxy. Two InAs quantum dots structures with similar active regions grown on GaAs and Si substrates using strain reducing layer consisting of InAs QDs/6 nm In0.15Ga0.85As have been investigated. Atomic Force Microscopy, Transmission Electron Microscopy, and photoluminescence have been used for the characterization of the samples. We have observed a red shift of the InAs QD photoluminescence peak energy for the sample grown on Si substrate as compared to the sample grown on GaAs substrate, which was associated with residual biaxial strain from the Si/GaAs heterointerface. This red-shift of the photoluminescence peak energy is accompanied by a broadening of the photoluminescence spectrum from ∼31 meV to a value of ∼46 meV. This broadening is attributed to the quantum dots size inhomogeneity increase for samples grown on Si substrate. This result open new insights for the controlling the emission of InAs quantum dots for photonic devices integration using Si substrates.
In the era of digitalization, the number of electronic text documents has been rapidly increasing on the Internet. Organizing these documents into meaningful clusters is becoming a necessity by using several methods (i.e., TF-IDF, Word Embedding) and based on documents clustering. Document clustering is the process of dynamically arranging documents into clusters such that the documents contained within a cluster are very similar to those contained inside other clusters. Due to the fact that traditional clustering algorithms do not take semantic relationships between words into account and therefore do not accurately represent the meaning of documents. Semantic information has been widely used to improve the quality of document clusters by grouping documents according to their meaning rather than their keywords. In this paper, twenty-five papers have been systematically reviewed that are published in the last seven years (from 2016 to 2022) linked to semantic similarities which are based on document clustering. Algorithms, similarity measures, tools, and evaluation methods usage have been discussed as well. As result, the survey shows that researchers used different datasets for applying semantic similarity-based clustering regarding the text similarity. Hereby, this paper proposes methods of semantic similarity approach-based clustering that can be used for short text semantic similarity included in online laboratories repository.
The Jacobi elliptic function expansion method is one of the most powerful tools for exploring exact solutions of nonlinear partial differential models, which is used in this work to characterize the interaction between one long longitudinal wave and one short transverse wave propagation in a generalized elastic medium. First, we applied a wave transform to the proposed system of equations and obtained an ordinary differential equation. We obtain the values of involved free parameters after performing necessary operations, then substitute the obtained values to the ordinary differential equation by considering the constructed solutions to the ordinary and then to the partial differential equation. As a result, different structures of solutions are constructed such as solitary dark–bright, dark, bright, singular, trigonometric function, Jacobi elliptic function, and hyperbolic function solutions. In order to illustrate the tsunami and tidal oscillations, we draw 3D surfaces and 2D graphics for the obtained solutions by giving a specific value for the involved parameters under the given conditions.
The [3+2] cycloaddition (32CA) reaction of N-methyl-C-(4-hydroxylphenyl) nitrone 1 and maleic anhydride 2 has been investigated using molecular electron density theory (MEDT) at the MPWB95/6-311++G(d,p) computational level. This 32CA reaction undergoes two stereo- and stereoisomeric reaction paths to form two different products 3 and 4. An electron localization function (ELF) study predicts that the N-methyl-C-(4-hydroxylphenyl) nitrone 1 has a zwitterionic character and it takes place through a one-step mechanism, with activation enthalpies in between 17.48 and 23.41 kJ mol⁻¹ in the gas phase. The CDFT indices are used to forecast the global electron density flux from the strong nucleophilic N-methyl-C-(4-hydroxylphenyl) nitrone 1 to the electrophilic maleic anhydride 2. These exergonic 32CA reactions have negative Gibbs free energy along the endo and exo stereochemical routes. The endo stereochemical process is favored over the exo stereochemical pathway due to the increased thermodynamic stability of the cycloadduct. Bonding evolution theory (BET) predictions for the endo and exo routes indicate a one-step process with early transition states, which is consistent with the ELF topological investigation at the transition states.
Due to the importance and efficiency of heat transfer in industrial equipment, studying refrigerants to improve their efficiency in heating or cooling attracted much attention. In this paper, the molecular dynamic (MD) simulation method is employed to study refrigerant nano-oils' heat transfer capability inside an aluminium nanochannel. In the first part, the effects of oil type, including ester and hydrocracked, on thermal behaviour. The thermal performance of simulated samples is examined by changing the heat flux (HF) and thermal conductivity (TC). The results reveal that after 10 ns, the TC of the oils based on ester and hydrocracked reached 0.14 and 0.33 W/m.K, and the HF reached 511 and 793 W/m², respectively. The obtained numerical results indicate a better thermal behavior for hydrocracked oil, which can also transfer more heat. Therefore, the hydrocracked has been chosen as the based oil for the rest of the research. On the other hand, different percentages of hybrid nanoparticles of Cu and Fe3O4 nanoparticles and carbon nanotubes are added to the hydrocracked oil. By increasing the nanoparticles’ percentage from 1 to 4%, the HF increased from 792 and 911 W/m², and the TC also raised from 0.40 and 0.52 W/m.K. According to the results, adding the hybrid nanoparticles into the oil sample improved its thermal behavior. It is hoped that the results obtained in this research be useful and applicable in the industry field.
In nanozyme-based assays, increasing enzymatic activity is very desirable for enhancing sensitivity and lowering the detection limit. In this study, novel Mn doped cobalt oxide nanosheets ([email protected]3O4 NSs) were synthesized by hydrothermal process. The obtained [email protected]3O4 possessed enhanced dual-enzyme mimetic, oxidase and peroxidase, and can catalytically oxidize of 3, 3′, 5, 5′-tetramethylbenzidine (TMB), to blue product of oxidized TMB. The enzyme kinetics were well-described mathematically using a common Michaelis-Menten and Lineweaver Burk model. The enzyme kinetics constant (Km) was found to be 0.15 mM, which is relatively low comparing with pure Co3O4 nanosheets (0.35 mM) and natural enzyme HRP (0.434 mM). Therefore, the efficient colorimetric method was achieved for determination of H2O2 and ascorbic acid. The limit of detection (LOD) of H2O2 was 8.0 μM and the linear range was 20–200 μM based on direct turn on of the peroxidase-like activity of [email protected]3O4. While, for ascorbic acid detection based on turn-off approach, the linearity range for the ascorbic acid was 1–8 μM with LOD of 0.4 μM. Moreover, the colorimetric system exhibited good stability and selectivity toward the detection of ascorbic acid effectively in real samples (vitamin C tablets) with satisfactorily accuracy and precision.
Nanochannels (NCs) are hopeful structures for mass transfer (MT) and heat transfer (HT) procedures in actual usages. Prior reports displayed the atomic behavior of various fluids inside perfect NCs. This examination uses the molecular dynamics simulation (MDS) approach to examine the impact of obstacle numbers on argon flow inside Platinum-based NCs. Simulation outputs were presented by calculating physical quantities like temperature (T), potential energy(PE), density (D)/temperature (T)/velocity (V) profiles, and interaction energy(IE). MDS results show that as the number of obstacles (N.Os) increases, the maximum D increases from 0.093 to 0.099 atom/Å³. The maximum V decreases from 0.0031 to 0.0025 Å/ps by the expansion of the N.Os. The maximum T decreases from 329.46 to 318.43 K. By the N.Os increments, the fluid particles' oscillations (FP) and their temperature also decrease. This mechanism can reduce the temperature in the HT process. In addition, with the enhancement of the N.Os from 1 to 4, the IE increases from -60.52 to 70.86 - eV. This increase in IE can reduce the atomic stability of platinum NCs. This behavior reduces the lifetime of NCs in heat/mass transfer processes. Therefore, it is expected that with the outcomes of the current examination and the control of the N.Os, we will be able to optimize the various processes like MT and HT for industrial purposes.
Various fluids are implemented for mass/heat transfer procedures in industrial applications. These structures' behavior inside the metallic nanochannels (NCs) in the presence of the obstacle was described. To this end, the Molecular Dynamics Simulation (MDS) method is performed by the LAMMPS package. The various atomic forces in defined structures are defined using Universal Force Field (UFF) and Embedded Atom Model (EAM). In addition, physical parameters such as temperature (T), potential energy (PE), Radial Distribution Function (RDF), profiles of density (D)/velocity(V)/T, position histogram, trajectory lines, and interaction energy are reported for nanofluid (NF) behavior description. MDS results display the equilibrium of Ar (as fluid) and Pt (as NC) in the presence of obstacles after t=20 ns. Also, our simulations predict that the obstacles increase/decrease the average values of fluid adsorption/mobility inside the NC.
Objective This study aimed to investigate the breakthrough infection rate and safety profile of the AstraZeneca vaccine. Methods The breakthrough COVID-19 infection rate was defined as a positive polymerase chain reaction test 14 days after the vaccine dose. Safety was assessed as local reactions and systemic events that occurred within 14 days of receiving vaccine doses. Results The average age of the 265 participants was 43.85 years and 169 (63.77%) were male. . After the second dose, 18 (6.71%) participants contracted the infection. The SARS-CoV-2 delta variant was responsible for all infections but no participants required hospitalisation. We found significant correlations between post-vaccination IgG levels and post-vaccination infection (P = 0.001; odds ratio [OR] = 0.959; 95% Confidence interval [CI]: 0.944–0.974), and between a history of previous infection and post-vaccination infection rates (P = 0.005; OR = 0.1; 95%CI:0.009–0.6). IgG levels were significantly higher in women than in men (P = 0.006) and in patients who developed side effects after vaccination than in those without side effects (P = 0.04). A significant association was found between a history of COVID-19 infection prior to vaccination and IgG levels (P = 0.001). Conclusions The vaccine is effective in preventing severe disease, with few side effects.
The boiling process is an efficient and effective transfer of heat. Generally, different parameters such as temperature, pressure, external forces, etc., amend the nanofluid's pool boiling heat transfer (PBHT) rate. The present article uses molecular dynamics (MD) simulation to study the efficacy of different external forces(Efs) and heat fluxes (HF) on the atomic and PBHT of water/Fe nanofluid (NF). This study is performed in a microchannel (MC) with Fe-walls. The atomic behavior of the simulated structure is examined using the change in maximum temperature (T), velocity(v), and density(D), and the PBHT is studied by the phase change time (PCT) and HF. Results show that the maximum of the T, V, and D increase with increasing the EF and heat flux. Numerically, with increasing EF from 0.001 to 0.005 eV/Å, the maximum od D, maximum of V, and maximum of T increase from 0.033 atom/Å³, 0.038 Å/fs, and 789 K to 0.034 atom/Å³, 0.039 Å/fs, and 900 K, respectively. Also, the result appears that the transferred HF increases by improving the applied EF, and the PCT reduces from 0.33 to 0.32 ns. So, the PBHT in the NF is improved with increasing EF. On the other hand, the increase in external HF led to a reduction in the PCT (from 0.33 to 0.21 ns).
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