Analysis and Assessment of the Effects of Corrosive Hydrogen Media on the Stress-Strain State of a Spherical Titanium Alloy Shell

We consider the creation of a mathematical model describing the effect of corrosive hydrogen environment on the stress state of a hollow spherical shell made of titanium alloy grade VT1-0, the load is evenly distributed throughout the shell. The solution of the problem in practice was carried out by two-step method of sequential perturbation of parameters using MatLab and Maple programs. To solve the system of solving differential equations the finite difference method was applied. The solution of the diffusion equation of the aggressive hydrogen medium has been considered and the obtained solution has been compared with the results of the classical theory which does not take into account the aggressive effect of the corrosive medium.

The study results of the filtration process in the ground dams body and its chemical effect on piezometers

The article describes the definition of filtration flow gradients in the dam's body on the example of the Kattakurgan reservoir, the analysis of the reasons for their change in cross-section. Evaluation of the aggressiveness of the filtration flow in the dam's body plays an important role in ensuring the stability of the reservoir dam and its parts. To assess the aggressiveness of the filtration flow in the dam's body, it is necessary to know the action pattern of the filtration water in the reservoir dam and its effect on the elements of the dam. In addition, the chemical composition of the water in the piezometers was analyzed in the laboratory to determine the aggressive effect of sulfate elements on the piezometers and their corrosion. Measures on the observations of systemic piezometers were also mentioned.

Flesh firmness examination of scab-resistant apple varieties in a storage experiment

Of the different physical characteristics of fruits, one of the most essential qualities is flesh firmness, as is an important parameter when selling fresh apples, processing the fruit (processing industry) and during its storage. In the scope of our research, we examined five apple varieties originating from the Derecske horticultural site of KITE cPlc. in 2016. The plantation was planted to be suitable for intensive apple production. Samples were collected at the time of maturity (August-October) of the given variety. The five examined apple varieties (Gaia, Isaaq, Modí, Smeralda and Fujion) are all resistant to apple scab (fungal disease caused by Venturia inaequalis). The two-month storage experiment was conducted at 16-17 °C, which had an aggressive effect on our stored apples. Flesh firmness, weight and diameter were measured on three dates for each of the five apple varieties. Our results were evaluated using IBM SPSS Statistics 20 software. We aimed to compare flesh firmness, weight and diameter of the five apple varieties and their changes during storage. Isaaq (86.34 N/cm2), Modí (94.06 N/cm2) and Fujion (84.90 N/cm2) had outstanding initial flesh firmness results. The Modí apple variety provided the best storage parameters.

Analysis of a Novel Two-Lane Hydrodynamic Lattice Model Accounting for Driver’s Aggressive Effect and Flow Difference Integral

In the actual traffic environment, the driver’s aggressive driving behaviors are closely related to the traffic conditions at the next-nearest grid point at next time step. The driver adjusts the acceleration of the driving vehicle by predicting the density of the front grid points. Considering the driver’s aggressive effect and the relative flow difference integral, a novel two-lane lattice hydrodynamic model is presented in this paper. The linear stability method is used to analyze the current stability of the new model, and the neutral stability curve is obtained. The nonlinear analysis of the new model is carried out by using the theory of perturbations, and the mKdV equation describing the density of the blocked area is derived. The theoretical analysis results are verified by numerical simulation. From the analysis results, it can be seen that the driver’s aggressive effect and the relative flow difference integral can improve the stability of traffic flow comprehensively.

Reducing restraint with clozapine in involuntarily admitted patients with schizophrenia

IntroductionIn the entire world, restraint and seclusion are common interventions in psychiatric in-patient settings due to aggressive behavior.ObjectivesOur objective was to test for the immediate anti-aggressive property of clozapine compared to other antipsychotic treatments in an enriched cohort with high rates of restraint during early hospitalization.MethodsWe present a retrospective chart review in all involuntary admissions with schizophrenia during 2011–2014 in Psychiatry and Neurology Hospital, Brasov, Romania. Timing and number of restraints in addition to clinical, demographic and treatment characteristics were extracted. Based on our earlier observation of clinical efficacy of early, fast titration of clozapine, we tested the hypothesis that clozapine treatment was associated with reduced use of restraint, and with longer restraint-free periods.ResultsIn 115 patients with schizophrenia (age = 39.7 ± 11.1 years; male = 59%) involuntarily admitted due to externalized (74.78%) or self-directed violence (25.22%), restraint was used in 89.6%; with a median duration of 3 hours until restraint past admission. Antipsychotics used immediately after hospitalization included haloperidol (70.4%), clozapine (11.3%), olanzapine (10.4%) and other second-generation antipsychotics (7.9%). Comparison of restraint characteristics favored immediate clozapine use with highly reduced rates of restraint (38.5% vs.95.6%. P < 0.001) and significantly extended hours until restraint ([118 h,24 h, 426 h] vs.[3 h,0.25 h, 48 h]; median; 25th, 75th percentile; P < 0.001) relative to the remaining cohort. These effects remained highly significant after controlling for potential moderators of restraint use in multivariate models.ConclusionsThese retrospective data suggest an early anti-aggressive effect of clozapine during the immediate use of clozapine in highly problematic patients.Disclosure of interestThe authors have not supplied their declaration of competing interest.

A new macro model of traffic flow by incorporating both timid and aggressive driving behaviors

In this paper, a novel macro model is derived from car-following model by applying the relationship between the micro and macro variables by incorporating the timid and aggressive effects of optimal velocity on a single lane. Numerical simulation shows that the timid and aggressive macro model of traffic flow can correctly reproduce common evolution of shock, rarefaction waves and local cluster effects under small perturbation. Also, the results uncover that the aggressive effect can smoothen the front of the shock wave and the timid effect results in local press peak, which means that the timid effect hastens the process of congregation in the shock wave. The more timid traffic behaviors are, the smaller is the stable range. Furthermore, the research shows that the advantage of the aggressive effect over the timid one lies in the fact that the aggressive traffic behaviors can improve the stability of traffic flow with the consideration of incorporating timid and aggressive driving behaviors at the same time.

Crude Oil Corrosion Fatigue of L485MB Pipeline Steel

An investigation was made into the fatigue properties of L485MB (X70) pipeline steel after 13 yr of exploitation as a crude oil pipeline material. Fatigue tests in zero-to-tension loading were carried out (i) in air, (ii) in crude oil, (iii) in a mixture of crude oil with rainwater, and (iv) in water separated from the crude oil phase. The aim of the investigation was to assess the degree of degradation of the fatigue properties of this steel due to the action of environments typical for crude oil processing and transport. The results are not directly comparable to any corrosion fatigue experienced by the crude oil pipeline, since the strain rate for the tests was higher by an order of five than the strain rate observed in typical loading cycles. The results showed that crude oil and a mixture of crude oil with rainwater had no aggressive effect on the steel in the sense of reducing its fatigue characteristics, while the separated water had an aggressive effect.