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This paper presents the modeling of the existing crude oil separation process in a system consisting of two rectification columns with side drafts operating at higher pressure. The composition of the crude oil was approximated by a model mixture of hydrocarbons. The installation calculations have been performed for two different model compositions containing 32 and 10 different hydrocarbons. The whole technological process was based on the assumption that the feed stream, containing a model crude oil, was introduced to the first column, and then the other expected products (different petroleum fractions), characterized by their respective boiling points, were collected (side drafts) from the appropriate trays of the distillation columns. The obtained calculation results for both of the model crude oils were compared with the results obtained in the existing petroleum process and discussed from the point of view of their practical applications. The detailed data concerning size, composition, and process parameters for all the streams of the investigated installations, as well as the necessary energy expenditure for each of the columns, have been determined. Moreover, some recommendations are presented for the modeling and optimization of industrial distillation processes of very complex, multi-component systems using simpler model compositions. [ABSTRACT FROM AUTHOR]

Background and Objectives: Hypertension increases the risk of developing atherosclerosis and arterial stiffness, with secondarily enhanced wall stress pressure that damages the artery wall. The coexistence of atherosclerosis and hypertension leads to artery stenosis and microvascular angiopathies, during which the intravascular mechanical hemolysis of red blood cells (RBCs) occurs, leading to increased platelet activation, dysfunction of the endothelium and smooth muscle cells due to a decrease in nitric oxide, and the direct harmful effects of hemoglobin and iron released from the red blood cells. This study analyzed the impact of hypertension and physical exercise on the risk of hemolysis in the left coronary artery. Methods: To analyze many different cases and consider the decrease in flow through narrowed arteries, a flow model was adopted that considered hydraulic resistance in the distal section, which depended on the conditions of hypertension and exercise. The commercial ANSYS Fluent 2023R2 software supplemented with user-defined functions was used for the simulation. CFD simulations were performed and compared with the FSI simulation results. Results: The differences obtained between the FSI and CFD simulations were negligible, which allowed the continuation of analyses based only on CFD simulations. The drops in pressure and the risk of hemolysis increased dramatically with increased flow associated with increased exercise. A relationship was observed between the increase in blood pressure and hypertension, but in this case, the increase in blood pressure dropped, and the risk of hemolysis was not so substantial. However, by far, the case of increased physical activity with hypertension had the highest risk of hemolysis, which is associated with an increased risk of clot formation that can block distal arteries and lead to myocardial hypoxia. Conclusions: The influence of hypertension and increased physical exercise on the increased risk of hemolysis has been demonstrated. [ABSTRACT FROM AUTHOR]

Background/Objective: Atherosclerosis is becoming increasingly common in modern society. Owing to the increasing number of complex angioplasty procedures, there is an increasing need for training in cases where the risk of periprocedural complications is high. Methods: A procedure was developed to obtain three-dimensional (3D) models and printing of blood vessels. The mechanical and optical properties of the printed materials were also examined. Angioplasty and stent implantation were tested, and the phantom was compared with the clinical data of patients who underwent interventional treatment. Both laser techniques and cone-beam computed tomography of the phantoms were used for comparison. Results: The printed material exhibited mechanical parameters similar to those of blood vessel walls. The refractive index of 1.473 ± 0.002 and high transparency allowed for non-invasive laser examination of the interior of the print. The printed models behaved similarly to human arteries in vivo, allowing training in treatment procedures and considering vessel deformation during the procedure. Models with stents can be analyzed using laser and cone-beam computed tomography to compare stents from different manufacturers. Conclusions: The developed methodology allows for simple and time-efficient production of personalized vessel phantoms. [ABSTRACT FROM AUTHOR]

Atherosclerosis affects human health in many ways, leading to disability or premature death due to ischemic heart disease, stroke, or limb ischemia. Poststenotic blood flow disruption may also play an essential role in artery wall impairment linked with hemolysis related to shear stress. The maximum shear stress in the atherosclerotic plaque area is the main parameter determining hemolysis risk. In our work, a 3D internal carotid artery model was built from CT scans performed on patients qualified for percutaneous angioplasty due to its symptomatic stenosis. The obtained stenosis geometries were used to conduct a series of computer simulations to identify critical parameters corresponding to the increase in shear stress in the arteries. Stenosis shape parameters responsible for the increase in shear stress were determined. The effect of changes in the carotid artery size, length, and degree of narrowing on the change in maximum shear stress was demonstrated. Then, a correlation for the quick initial diagnosis of atherosclerotic stenoses regarding the risk of hemolysis was developed. The developed relationship for rapid hemolysis risk assessment uses information from typical non-invasive tests for treated patients. Practical guidelines have been developed regarding which stenosis shape parameters pose a risk of hemolysis, which may be adapted in medical practice. [ABSTRACT FROM AUTHOR]

Wireless Sensor Networks (WSNs) have existed for many years and had assimilated many interesting innovations. Advances in electronics, radio transceivers, processes of IC manufacturing and development of algorithms for operation of such networks now enable creating energy-efficient devices that provide practical levels of performance and a sufficient number of features. Environmental monitoring is one of the areas in which WSNs can be successfully used. At the same time this is a field where devices must either bring their own power reservoir, such as a battery, or scavenge energy locally from some natural phenomena. Improving the efficiency of energy harvesting methods reduces complexity of WSN structures. This survey is based on practical examples from the real world and provides an overview of state-of-the-art methods and techniques that are used to create energyefficient WSNs with energy harvesting.

Molybdenum disulfide (MoS2) is an emerging material with exciting properties. Many consider it an excellent catalyst, particularly for hydrogen evolution reaction. Currently, it is used on a larger scale as a lubricant. The size of MoS2 is a crucial parameter defining its properties. A preparation method that is easily scalable and cheap is currently being sought. A solution might be a wet chemical synthesis method carried out in an impinging jet reactor. The simple design of the reactor and the possibility of continuous operation make this method unique. In this study, the influence of the reactor was investigated using numerical simulations. The S-type reactor showed better mixing and more control over the working conditions than T-type. Therefore, the S-type reactor was chosen as better for nanoparticle synthesis. We also investigated the influence of the process conditions on the size of the precipitated MoS2 particles. The best operating conditions (i.e., Mo concentration of 0.2 mol/m3, reagent flow velocity of 20 mL/min, reaction temperature of 20 °C) were chosen to obtain the smallest particles (~200 µm). Additionally, two different reducing agents were also tested. The use of formic acid allowed obtaining smaller particle sizes but these were less stable than in the case of citric acid. [ABSTRACT FROM AUTHOR]