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It is more important to improve and complete the wastewater process in order to reuse and return it to the production line. In this study, the hydrogen peroxide/ozone process (Peroxone) was investigated as a supplementary step in paper mill wastewater treatment to reduce the amount of chemical oxygen demand and remove E. coli. In this regard, using the Box-Behnken Design method based on the response surface method to optimize and investigate the effect of three variables governing the ozonation process, including the amount of hydrogen peroxide consumed (ml), the amount of ozone input (mg/min) and ozonation time (min) were used. The results showed that the amount of ozone and hydrogen peroxide had the greatest effect for reducing COD (up to about 75%). Also, all three variables have played a significant role in increasing the efficiency of the Peroxone process and even completely eliminating E. coli. In determining the optimal conditions, the amount of ozone (146 mg/min), the amount of hydrogen peroxide (2ml) and the duration of ozonation (23 min), the lowest amount of residual COD (73 mg/L) and the highest efficiency (75% removal of E. coli) are predicted. The results showed that due to the interaction of ozone and hydrogen peroxide, the peroxone process performance was less efficient than the ozonation process alone.

In this research, the ozonation process has been used as a supplementary stage of purification to reduce the amount of chemical oxygen demand and remove bacteria, especially E. Coli, from the effluent of the paper industry. Box-Behnken Design statistical method is used to optimize the treatment conditions. In this method, the effect of three variables governing the ozonation process, including the initial pH of the effluent, the amount of input ozone (mg/min) O3 and the duration of ozonation (min) t, was investigated. The results showed that the amount of input ozone and pH had the greatest impact on reducing COD (up to about 80%). Also, the maximum efficiency of the ozonation process for the complete removal of E. Coli was seen in acidic conditions with high amounts of ozone and increasing the duration of ozonation. According to the results, it was found that ozone in molecular form and by direct attack in acidic environments played a role in the destruction of pollutants. Design Expert software was used to determine the optimal conditions, minimize residual COD and maximize the efficiency of the ozonation process. The values of pH=5.2, ozone amount (131mg/min) and duration (23 min) are predicted to reach the lowest residual COD value (48 mg/L) and the highest efficiency (100% removal of E. Coli). According to the investigations carried out in this research, it can be concluded that the use of ozonation process to reduce COD and effectively remove E. Coli from the waste water of paper industry is a promising complementary method.

Background and aim: Co-authorship increases the possibility of visibility of articles and reflection of their findings in the research of others. The aim of the present study was to determine the number of authors and the number of citations of hot papers in the Science Citation Index Expanded (SCI-E) in the Web of Science (WOS). Materials and methods: This quantitative study was conducted using the scientometric approach. The research community consisted of 3,475 hot papers in the field of science in WOS from 2020 to 2021. The Spearman correlation coefficient test was used to examine the relationship between the citations of the articles and the number of authors. Data were collected and analyzed using BibExcel, Excel, and SPSS. Findings: The hot papers showed a wide range, from one to 2718 authors. Moreover, a significant correlation was found between the number of authors and the number of citations of hot papers in the field of science (p= 0.000, n= 3475, r= 0.161). Therefore, statistically, there was a positive correlation between the two variables. Conclusion: Higher scientific collaboration in hot articles increases the number of citations and ultimately increases the visibility of these articles.

In this paper, the thermo-electric, phonon, electronic, and optical properties of the C3N monolayer have been investigated using the Wien2K computational code based on first principles calculations in the framework of the density functional theory. The study of electronic properties shows the behavior of non-magnetic semiconductors with an indirect gap with a value of 0.5 electron volts for this two-dimensional structure. Also, optical properties such as dielectric function, reflection, energy loss function, absorption coefficient, and optical conductivity are calculated. C3N monolayer is optically anisotropic in z and x direction, which according to the refractive index diagram leads to birefringence, which is a key parameter for this compound's linear optical performance. The results provide a fundamental understanding of the design of composite structures used in nanodevices based on two-dimensional advanced materials. The linear response approach along the symmetric points calculates the phonon dispersion diagram. The results indicate the absence of negative modes in the phonon spectrum, indicating that the structure is dynamically stable. Investigating the thermoelectric properties of the C3N monolayer using the semi-classical Boltzmann theory shows that this monolayer has a value coefficient (ZT) close to one at room temperature and temperatures lower than room temperature. As a result, it can be proposed as a candidate for thermoelectric applications.

Many non-classicality indicators are used to measure the quantum effects of different systems. Kenfack's and Sadeghi's non-classicality indicators are introduced regarding the amount of Wigner distribution function's negativities and interferences in phase space quantum mechanics, respectively. Kenfack’s non-classicality indicator is used for cases just in the Wigner representation, whereas Sadeghi’s non-classicality indicator is effectively, applied for some real distribution functions. In this paper, we investigate these non-classicality indicators for the entangled photon number states in the Wigner, Husimi, and Rivier representations. It is shown that for a two-level entangled state, Sadeghi's indicator has more benefits to measure entanglement with respect to Kenfack's indicator. For the two-level entangled state, we also show a correspondence between Sadeghi's non-classicality indicator and the Von Neumann entropy. It is also shown that for the superposition of the squeezed number state and ground number state, the squeezing parameter affects the entanglement feature and Sadeghi's non-classicality indicator increases with the increase of the squeezing parameter.

Using the experimental results and data, the thermodynamic characteristics and thermal analysis of the electrical arc of torch electrodes and energy deposition in the waste-incinerator primary designed chamber were investigated. The temperature of arc in the intermediate electrode which is called the float nozzle was measured at 7000-8000 Kelvin based on the input power of 2 kW. The plasma plume temperature implied to be lower than the arc temperature according to the cold gas flow in the nozzle. The efficiency of energy transferring to the plasma plume is dependent on the geometrical electrode and nozzle design, and gas flow rate. After ten seconds, the chamber temperature was measured at 1193 Kelvin by thermocouple with the performance of electrical elements and plasma torch. The chamber temperature increasing in an adiabatic process was calculated at 1230 Kelvin after this time. According to the isothermal approach, the heat flow rate, and conduction loss calculation, the chamber temperature was obtained at about 900-1000 Kelvin. Using two approaches with inevitable approximations, the calculated temperature ranges for arc and plasma plume energy estimation have reasonable compatibility and this led to the road map of optimization and development for future torch planning and waste-incinerator chamber design.

In this work, considering the moment theory propagation of the laser beam with relativistic intensity in thermal quantum plasma is studied. Using the Maxwell equation and dielectric function obtained by the quantum hydrodynamic model, the mathematical equation for the laser beam width parameter is achieved and solved numerically by the fourth-order Runge-Kutta method. The results show that the stronger self-focusing effect is found in the moment theory compared to paraxial approximation. Also, similar to paraxial approximation, with growing Fermi temperature, plasma density and laser intensity, the oscillation frequency of the beam width parameter increases and focusing length decreases which means improving the self-focusing effect. Furthermore, it is seen that behaviors of the critical radius are not similar in the two theories, as in the moment theory, with increasing laser intensity, critical radius decreases until it becomes independent of the beam intensity, but in the paraxial approximation, the critical radius after a minimum value is enhanced with increasing laser intensity.

Gene expression is known as a phenomenon that shapes human life. This very complex phenomenon is formed from two stages: transcription and translation. In this study, we used the Nose-Hoover thermostat to model the effect of ambient temperature on gene expression since temperature regulates the biological clock of living systems. We have used the Lyapunov exponent approach to investigate the effect of control parameters on gene expression, including the degradation rates of messenger RNA and proteins, and to find critical points (phenomenon boundary limits), mRNA, and protein level boundary values. The rate of degradation in the process of protein synthesis has been investigated with the help of the Lyapunov exponent approach. According to this study, the optimal temperature for the production of mRNA molecules by Escherichia coli bacteria is 306 Kelvin. The study also used the chaos approach to show that the faster the mRNA molecules are degraded, the more they are transcribed, and the more chaotic the system becomes.

Entanglement plays a fundamental role in the field of quantum computing and quantum communication. In real conditions, a physical system is never isolated and inevitably interacts with its surroundings. Temperature is one of these effects that mainly reduces entanglement. In real conditions, the system is at a non-zero temperature, which will lead to a mixed state. Therefore, in the present work, the combined thermal entanglement of electron spin-oscillation in an anisotropic two-dimensional quantum dot is investigated using the negativity criterion. The results show that the combined entanglements are strongly dependent on the changes of the controllable parameters, such as the Rashba parameter and the magnetic field. The thermal entanglement between the spin and the assembly of oscillators is zero at absolute zero temperature and reaches a maximum with increasing temperature and then tends to zero asymptotically. This temperature, at which the amount of entanglement reaches its maximum value, can be controlled by changing the magnetic field and the coupling of the Rashba parameter. These two factors also control the rate of reaching the asymptotic state. These results provide a way to control the degree of entanglement between electron degrees of freedom, which is a fundamental requirement of quantum information processing.

In the last two decades, photonic crystals and structures that are based on them (photonic structures) have been examined and have been widely utilized in various optical applications. In this article, a theoretical and numerical model for the propagation of electromagnetic waves in multilayer dielectric structures is developed. The propagation of ultra-short light pulses in multilayer media and microresonators is investigated, and the energy reflection and transmission coefficients depending on the parameters of the environment and duration of the optical pulse are calculated. A method for calculating the transmission and reflection spectra of one-dimensional photonic crystal based on FDTD modeling with the emission of ultra-short optical pulses is proposed. To calculate the transmission and reflection spectrum of a one-dimensional photonic crystal and to simulate the propagation of ultra-short light pulses, in multilayer dielectric structures and microresonators, based on the numerical solution of Maxwell's equations with the finite difference approximation in the space-time domain, is performed.