Bimolecular Recombination Reactions: Low Pressure Rates in Terms of Time-Dependent Survival Probabilities, Total J Phase Space Sampling of Trajectories, and Comparison with RRKM Theory

We consider the bimolecular formation and redissociation of complexes using classical trajectories and the survival probability distribution function P(E,J,t) of the intermediate complexes at time t as a function of the energy E and total angular momentum quantum number J. The P(E,J,t) and its deviation from single exponential behavior is a main focus of the present set of studies. Together with weak deactivating collisions, the P(E,J,t) and a cumulative reaction probability at the given E and J can also be used to obtain the recombination rate constant k at low pressures of third bodies. Both classical and quantum expressions are given for k in terms of P(E,J,t). The initial conditions for the classical trajectories are sampled for atom−diatom reactions for various (E,J)’s using action-angle variables. A canonical transformation to a total J representation reduces the sampling space by permitting analytic integration over several of the variables. A similar remark applies for the calculation of the density of states of the intermediate complex ρ and for the number of states N* of the transition state as a function of E and J. The present approach complements the usual approach based on the rate of the reverse reaction, unimolecular dissociation, and the equilibrium constant. It provides results not necessarily accessible from the unimolecular studies. The formalism is applied elsewhere to the study of nonstatistical aspects of the recombination and redissociation of the resulting ozone molecules and comparison with RRKM theory

A new approach for solving nonlinear Thomas-Fermi equation based on fractional order of rational Bessel functions

In this paper, the fractional order of rational Bessel functions collocation method (FRBC) to solve Thomas-Fermi equation which is defined in the semi-infinite domain and has singularity at $x = 0$ and its boundary condition occurs at infinity, have been introduced. We solve the problem on semi-infinite domain without any domain truncation or transformation of the domain of the problem to a finite domain. This approach at first, obtains a sequence of linear differential equations by using the quasilinearization method (QLM), then at each iteration solves it by FRBC method. To illustrate the reliability of this work, we compare the numerical results of the present method with some well-known results in other to show that the new method is accurate, efficient and applicable

Comparison of mathematical models and artificial neural networks for prediction of drying kinetics of mushroom in microwave vacuum dryer

Drying characteristics of button mushroom slices were determined using microwave vacuum drier at various powers (130, 260, 380, 450 W) and absolute pressures (200, 400, 600, 800 mbar). To select a suitable mathematical model, 6 thin-layer drying models were fitted to the experimental data. The fitting rates of models were assessed based on three parameters; highest R2, lowest chi square () and root mean square error (RMSE). In addition, using the experimental data, an ANN trained by standard back-propagation algorithm, was developed in order to predict moisture ratio (MR) and drying rate (DR) values based on the three input variables (drying time, absolute pressure, microwave power). Different activation functions and several rules were used to assess percentage error between the desired and the predicted values. According to our findings, Midilli et al. model showed a reasonable fitting with experimental data. While, the ANN model showed its high capability to predict the MR and DR quite well with determination coefficients (R2) of 0.9991, 0.9995 and 0.9996 for training, validation and testing, respectively. Furthermore, their predictions Mean Square Error were 0.00086, 0.00042 and 0.00052, respectively

Uncertainty analysis of a test bed for calibrating voltage transformers vs.Temperature

The paper addresses the evaluation of the uncertainty sources of a test bed system for calibrating voltage transformers vs. temperature. In particular, the Monte Carlo method has been applied in order to evaluate the effects of the uncertainty sources in two different conditions: by using the nominal accuracy specifications of the elements which compose the setup, or by exploiting the results of their metrological characterization. In addition, the influence of random effects on the system accuracy has been quantified and evaluated. From the results, it emerges that the choice of the uncertainty evaluation method affects the overall study. As a matter of fact, the use of a metrological characterization or of accuracy specifications provided by the manufacturers provides respectively an accuracy of 0.1 and 0.5 for the overall measurement setup

Real particle geodesics and thermodynamics of a black hole in Regular Schwarzschild-Anti de Sitter space-time

In this work, we illustrate the geodesics of real particles obtained numerically in a Regular Schwarzschild Anti-de Sitter (RSch-AdS) space-time. The behavior of these geodesics are considered depending on variation of effective parameters such as mass distribution, angular momentum and cosmological constant. Also, using the laws of thermodynamics of black holes, we will study and discuss some aspect of black hole (BH) described by this spacetime such as temperature, entropy, heat capacity and Gibbs free energy.Comment: 22 pages, 26 figure

Association of Serum Leptin with Prognostic Factors in Breast Cancer

Background: Nowadays, cytokines such as Leptin and adiponectin are introduced as prognostic factors which, according to some studies, are also associated with body mass index. This study aimed to determine serum leptin level and its relationship with prognostic factors in breast cancer patients.Methods: This case–control study was conducted in the oncology department of Tohid Hospital, Sanandaj, Iran, between 2019 and 2020. Hundred new cases of breast cancer patients with histological evidence were enrolled in this study. Additionally, 100 age-and BMI-matched healthy individuals were recruited as the control group. The serum leptin level was measured using the ELISA method.Results: Serum leptin levels were significantly higher in breast cancer patients compared to the control group (21.68 ± 9.16 vs 11.89 ± 4.45; p < 0.001). There was no significant relationship between plasma leptin levels with ER, PR, and HER2 expressions (p > 0.05). Also, no significant associations were noted between leptin levels and grading and disease staging (p > 0.05).Conclusion: The study found that leptin is higher in breast cancer patients than in healthy individuals, however, it did not prove that leptin is a predictive or prognostic factor.Keywords: leptin, breast cancer, staging, gradin

Effects of thermal cycles on interfacial pressure in MV cable joints

The use of medium voltage cable joints is mandatory when dealing with power cable faults and the installation of new lines. However, such an accessory is among the top causes of faults among the grid. To this purpose, one of the quantities monitored to understand the causes of such faults is the interfacial pressure between the insulating layers of the cable joint. In this work, the interfacial pressure between Cross-linked polyethylene (XLPE) and silicon rubber has been evaluated when the cable joint experiences thermal cycles. From the results, the pressure variation caused by the thermal cycles is demonstrated. Such a phenomenon may be connected to the generation of voids and weak spots that accelerate cable joint ageing. Therefore, proper comments and conclusions are drawn

The Effect of Transcranial Direct Current Stimulation on Relapse, Anxiety, and Depression in Patients With Opioid Dependence Under Methadone Maintenance Treatment: A Pilot Study

Background and Objective: Patients under methadone maintenance therapy (MMT) are susceptible to several complications including mental disturbances and risk of relapse. The present study was designed to evaluate the effects of tDCS on relapse, depression, and anxiety of opioid-dependent patients under methadone maintenance treatment (MMT). Methods: It was a randomized-clinical trial that conducted among 27 male patients referred to the outpatient addiction clinic of Ibn-e-Sina psychiatric hospital in Mashhad from July 2018 to May 2019. Participants were allocated to two treatment groups including intervention and sham groups. The intervention group received seven sessions of tDCS, in the F3 (cathode) and F4 (anode) areas of the brain, each one lasts 20 min, in two consecutive weeks. Depression, anxiety, and stress scale-21 (DASS-21) were measured before, during, and after the intervention in patients under MMT. Relapse on the morphine, cannabis, and methamphetamine was screened by urine dipstick tests of morphine, cannabis, and methamphetamine. Results: Depression, anxiety, and stress of participants were significantly reduced in the intervention group compared with the control after the seventh session of tDCS (P < 0.001, P=0.01, and P=0.01, respectively). In addition, the relapse rate showed no significant changes between the two groups (P=0.33). Conclusion: Overall, our study demonstrated that depression, anxiety, and stress of participants were significantly reduced after the seventh session of tDCS, but did not affect on the relapse rate. Therefore, it can be applied as a safe and effective technique to relieve mental disorder among receiving MMT. Clinical Trial Registration: http://www.irct.ir, identifier IRCT20180604039979N1. © Copyright © 2020 Sadeghi Bimorgh, Omidi, Ghoreishi, Rezaei Ardani, Ghaderi and Banafshe