bluuebunny/crossref_metadata_2025_split huggingface dataset:
Systematic review of extracellular vesicle‐based treatments for lung injury: are EVs a potential therapy for COVID‐19?
Authors: Khalaj Kasra , Figueira Rebeca Lopes , Antounians Lina , Lauriti Giuseppe , Zani Augusto 
Published: August 2020

ABSTRACTSevere COVID‐19 infection results in bilateral interstitial pneumonia, often leading to acute respiratory distress syndrome (ARDS) and pulmonary fibrosis in survivors. Most patients with severe COVID‐19 infections who died had developed ARDS. Currently, ARDS is treated with supportive measures, but regenerative medicine approaches including extracellular vesicle (EV)‐based therapies have shown promise. Herein, we aimed to analyse whether EV‐based therapies could be effective in treating severe pulmonary conditions that affect COVID‐19 patients and to understand their relevance for an eventual therapeutic application to human patients. Using a defined search strategy, we conducted a systematic review of the literature and found 39 articles (2014–2020) that reported effects of EVs, mainly derived from stem cells, in lung injury models (one large animal study, none in human). EV treatment resulted in: (1) attenuation of inflammation (reduction of pro‐inflammatory cytokines and neutrophil infiltration, M2 macrophage polarization); (2) regeneration of alveolar epithelium (decreased apoptosis and stimulation of surfactant production); (3) repair of microvascular permeability (increased endothelial cell junction proteins); (4) prevention of fibrosis (reduced fibrin production). These effects were mediated by the release of EV cargo and identified factors including miRs‐126, −30b‐3p, −145, −27a‐3p, syndecan‐1, hepatocyte growth factor and angiopoietin‐1. This review indicates that EV‐based therapies hold great potential for COVID‐19 related lung injuries as they target multiple pathways and enhance tissue regeneration. However, before translating EV therapies into human clinical trials, efforts should be directed at developing good manufacturing practice solutions for EVs and testing optimal dosage and administration route in large animal models.
Validation of the model for predicting VAC RTD photonics
Authors: Shasurin V D , Vetrova N A , Kuimov E V 
Published: August 2020

AbstractThis paper discusses the processes of current transfer in resonant tunneling diodes during the transition from the region of positive differential conductivity to the region of negative differential conductivity. The behavior features of the self-consistent potential and tunnel transparency coefficient in the region of peak stresses are demonstrated.
Properties of the thermoplastic starch/polylactic acid blends compatibilized by hyperbranched polyester
Authors: Mesias R , Murillo E A 
Published: August 2020

Abstract
With the aim of to contribute to the employ of new compatibilizing agent and to the preparation of biodegradable materials, in this study were obtained thermoplastic starch/polylactic acid blends and was evaluated the compatibilizing effect of a hyperbranched polyester polyol of second generation modified with polylactic acid in these blends. The blends were prepared in a torque rheometer. In all cases the weight ratio of thermoplastic starch/polylactic acid was 50/50 wt%. The proportions of the compatibility were 5 wt%, 10 wt% 15 wt%, and 20 wt% regard to the total amount of thermoplastic starch and polylactic acid. The blends were characterized by infrared, thermogravimetric, differential scanning calorimetry, X-ray diffraction, scanning electron microscopy and rheological analyses. Torque value decreased with the proportion of compatibilizing. Therefore, the compatibilizing also acted as plasticizing. By infrared analysis was observed that the increasing on the compatibilizing content enhanced the intensity of the signals corresponding to OH and C=O groups. By X-ray diffraction and differential scanning calorimetry analyses was observed a reduction of the crystallinity of the blends obtained with compatibilizing. By rheological analysis was evidenced the formation of a microstructure, which is able to elastically deform.
Evaluation of the methyl violet sorption capacity in waters with a bentonite based geopolymer material
Authors: López J A , Montaño A M , González C P , Medina L 
Published: August 2020

Abstract
In this study, bentonite geopolymer was used as a sorbent to remove methyl violet in aqueous solutions. Several parameters such as pH, sorbent dose and initial sorbate concentration were evaluated. The greater sorption effectiveness of bentonite geopolymer is observed at pH 2-3, and the greater sorption capacity of methyl violet by bentonite geopolymer occurs when the sorbent/sorbate ratio decreases. The study of sorption kinetics showed that the data fit the pseudo-second order model, where much of the sorption occurs during the first hour of contact, it was shown that the process prefers diffusion between pores. Sorption was adjusted to the isotherm of Langmuir, which indicated that the sorption is preferentially in monolayer. bentonite geopolymer proved to be an excellent candidate for removal of methyl violet in aqueous bodies.
Effects of synthesis conditions on sorption capacity methylene blue of coal gangue based geopolymer
Authors: Pinto L F , López J A , Montaño A M , González C P 
Published: August 2020

Abstract
In this work, coal gangue from the department of Cesar, Colombia, was used in the synthesis of a geopolymer by alkaline activation. The effect of the variation of the geopolymerization temperature and of four parameters on the composition of the activating solution was evaluated: SiO2/Al2O3, SiO2/Na2O, NaOH concentration and amount of H2O2. The geopolymer was characterized structurally by X-Ray diffraction and Fourier transform infrared spectroscopy. The sorption properties of methylene blue in aqueous solutions of geopolymer were studied through ultraviolet-visible spectrophotometry. Effects of various parameters such as pH value, geopolymer dose and initial concentration on the sorption capacity were studied. The adsorption kinetics and adsorption isotherm fitted well with the pseudo-second order model and Langmuir model, respectively. In the kinetic study it was evidenced that the adsorption equilibrium time was reached quickly, therefore this material constitutes a viable alternative for water decontamination.
Resilience in successful math and physics students
Authors: Rojas-Suárez J P , Vergel Ortega M , Gallardo Pérez H J 
Published: August 2020

AbstractResilience refers to the student’s ability to overcome emotional periods caused by adverse situations. In this sense, research aims to evaluate the relationship between academic performance in mathematics and physics and school success in higher education students. The research is framed within a quantitative, descriptive-comparative and micro-sociological methodological approach developed with data from primary sources. Data collection was transectional and the sample was 1500 students. The Wagnild and Young resilience scale was used. The results show that there is an important relationship between the level of demand, the application of mathematics and physics, abstraction and academic performance. Students develop emotional resilience skills that allow them to improve their quality of life. In conclusion, resilience is significantly related to all strengths of character, as well as to positive acceptance of change and personal competence. It was identified that, while resilience helps students to be more tolerant and to better understand what is happening in their environment, it is precisely in these challenges that the strengths of high educational performance are manifested. Successful students demonstrate skills in formal thinking, creative thinking, applying mathematics, physics and resilience, all of which impact on their quality of life.
Exploitation of chips and scrap aluminum through physical processes for the development of aluminum sheets and bars
Authors: Perez-Rangel N Y , Florez-Solano E , Hoyos Palacio L M 
Published: August 2020

Abstract
Colombia manufactures metals such as iron and aluminum, which consume a lot of energy to carry out these processes. There are many techniques to recycle metals and other elements to reduce the amount of energy in manufacturing processes, since smelting is generated with already manufactured materials, as in the case of aluminum, which uses recycled products such as soft drinks and beer cans. In addition, there is another type of scrap metal, such as aluminum shavings generated by machining processes, with an amount that varies from a small percentage to 70-90% of the original part. This project seeks to transform the aluminum shavings through physical processes with the application of temperature in aluminum material to be used again. The process begins with the collection of chips from mechanical workshops, in this case, from the machine tool laboratories of the “Universidad Francisco de Paula Santander, Ocaña, Colombia”. Standard procedures will be carried out before the casting process by developing firing curves and phase diagrams of aluminum, where the research focuses on generating aluminum metal to be used again in the laboratories of the same university.
Development of an automated system for the determination of thermal conductivity in granular materials
Authors: Espinel-Blanco E , Arévalo-Ruedas J H , Florez-Solano E 
Published: August 2020

Abstract
In many devices such as refrigerators, ovens, industrial kitchens, integrated circuits among others, where heat transfer is involved, it is important to know the thermal behavior of the material and the geometric model (cylindrical, spherical, etc.), with which such equipment will be built, to subsequently perform analysis of the parameters evaluated and thus enhance their efficiency. For this reason, it is important to know variables such as thermal conductivity, wall thickness, material, and geometry for new generation equipment. As a result, this work involved the construction of a test bench for the analysis of thermal conductivity in insulating materials, which began with the selection of the components that made up the device, such as resistors, types of thermocouples, specimen geometry, sensors, and finally, the construction of a data acquisition and analysis control system using Arduino and Labview. Subsequently, a device was obtained to measure the temperature in the cylindrical walls with different granular materials. This project was developed in an innovative way, where the thermal behavior of non-pure agglomerated granular materials will generate research in the study area, with the purpose of implementing it in different projects in which heat transfer is involved.
Comparative experimental analysis of thermodynamic performance of heat pipe and water in glass solar collectors
Authors: Rolon Ortiz H A , Krenzinger A , Ferreira C , Prieb C 
Published: August 2020

Abstract
Solar energy plays an important role in the alternative energy mix. Solar thermal energy is used in many processes such as domestic water heating, pasteurization, desalination, ambient heating and power generation. There are many devices designed to make use of the radiation coming from the Sun. Evacuated tube solar collectors are one of them. They can be classified according to the employed heat transfer mechanism: direct transfer (water in glass) and indirect transfer (heat pipe). This ongoing work aims to characterize both types of collectors and make an experimental comparative of the thermodynamic performance under the environmental conditions of Porto Alegre, Brazil. An experimental rig was set up with two collectors, one water-in-glass and the other a heat pipe type. Both collectors were connected in series on a tilted plane, together with a global radiation sensor and temperature sensors on interest points namely: inputs and outputs of collectors, air temperature and storage tank. These sensors were connected to a data logger system. Preliminary results show that the heat pipe collector has an average efficiency of 20% superior to the water-in-glass collector.
Numerical simulation of coarse particle pipeline transportation based on Eulerian Lagrangian model
Authors: Wang Sibo , Ding Xuewen , Wang Jin 
Published: August 2020

Abstract
In this paper, based on the Eulerian Lagrangian model, the non-phase change flow process of the coarse particle slurry in the horizontal pipeline is studied. The particle motion state is tracked, the dynamic characteristics of the coarse particle slurry in the pipeline transportation are explored, and the resistance characteristics of the pipeline and the operation stability under different conditions are analyzed. The comparison of the results of velocity distribution, concentration distribution and pressure curve with the empirical formula and experimental data shows that the simulation results are in good agreement with the calculation results of wasp formula and the experimental values of Roco&Balakrishnam, and the simulation can better describe the flow characteristics in the basin. In addition, the flow characteristics of particles are further analyzed according to the key factors such as the flow stability, the transition process and the critical deposition velocity of particles in different positions of the pipeline.
Study on Pollutant Emission in a Natural Draft Dry Cooling tower with Flue Gas Injection based on LES
Authors: Zhou Ying , Xu Haihong , Xu Zhen , Ding Li 
Published: August 2020

Abstract
This study investigated the Computational Fluid Dynamics (CFD) simulation of pollutant emission in a natural draft dry cooling tower (NDDCT) with flue gas injection. In order to predict the diffusion and distribution characteristics of the pollutant more accurately, Large Eddy Simulation (LES) was applied to predict the flow field and pollutant concentration field and compared with Reynolds Average Navier-Stokes (RANS). The relationship between pollutant concentration pulsation and velocity pulsation is emphatically analyzed. The results show that the maximum value of LES is about 43 times that of RANS for the prediction of pollutant concentration in the inner shell of cooling tower. Compared with RANS, LES can simulate flow field pulsation with a smaller scale and higher frequency.
Analysis of the Influence of Cyclone Structure Characteristics on Combustion Chamber Performance
Authors: Xiang Wenwei , Liu Jiang , Weng Peifen , Fu Zaiguo 
Published: August 2020

Abstract
The cyclone is an important part of the combustion chamber of the gas turbine and has a direct impact on the combustion performance in the combustion chamber. Therefore, it is of great value to study the structural characteristics of the cyclone. This paper firstly analyses the structural characteristics of cyclone that have the greatest impact on the performance of the combustion chamber through the relevant data and the structural parameters of the actual combustion chamber. Then appropriately simplifies the structure of the combustion chamber, designing a F-class combustion chamber with cyclone. Numerical simulation method is compared with the actual combustion chamber data to verify whether the design of the cyclone meets the requirements, thus preliminary determining the blade installation structure and the number of blades of the combustion chamber cyclone. In the end, using the model combustion chamber as a blueprint, adjust the blade characteristics of the cyclone for different installation angles (40°, 45°, and 50°) and the number of blades (6, 8, and 10). The combustion chamber model is simulated to determine that the flow field of the combustion chamber is the best when the angle is 45°and the number of blades is 8.
Numerical study on the heat transfer performance of a novel spray tower
Authors: Zhu Shengkui , Zhu Qunzhi 
Published: August 2020

Abstract
In order to reduce the moisture content of flue gas in coal-fired power plants, this paper puts forward a novel spraying system with upward spraying and downward gas flow (ST-UD). And the heat and mass transfer models of ST-UD in fluent were validated against experiment data. Then orthogonal simulation experiment was carried out to get the relationship between the four influence factors and the two evaluation indices. Through the range analysis and trend analysis, it can be found that the influence degree and the influence trend of factors on evaluation indices. The conclusion of this paper provides a reference for the heat-transfer performance optimization of other spray towers.
Structural Design and Numerical Simulation of FDM Molding Chamber Based on Thermal-Fluid-Structure Coupling
Authors: Liu Yajie , He Bing , Chen Pengfei 
Published: August 2020

Abstract
Four different design of FDM molding chamber with hot air circulation were proposed to meet the requirements of temperature uniformity of FDM rapid prototyping equipment. Fluid and solid domain model of FDM molding chamber was established by finite numerical simulation method in order to analyze the influence of the heating rod, blower, air inlet and outlet position on the temperature uniformity and air flow. The results show that the temperature uniformity and air velocity evenness are highest when the heating rod is located on both sides of the molding chamber, the blower is lied at the bottom, the air inlet is located above the left side, and the air outlet is above the right side. And the temperature uniformity is up to 99%. FDM molding chamber prototype was developed according to the simulation results. Air flows evenly, and temperature uniformity is as high as 97.66%, which verified the accuracy and effectiveness of the simulation results deeply.
Research on the Method of Improving the Flow Field Quality in the Elbow of the Water Flow Standard Device Based on the CFD Numerical Calculation Method
Authors: Li Haiyang , Li Xuejing , Zhang Ping , Liu Yiping , Yao Xinhong , Zhang Jinming 
Published: August 2020

Abstract
To solve the problems of secondary flow, turbulent vortex, and instability of the flow field in the elbow of the water flow standard device, some 3D geometric models of the elbow were established, and the flow field numeral calculations of the elbows were carried out based on the 3D models. The study shows that appropriately increasing the turning angle and the number of deflectors has a significant effect on improving the flow field quality in the elbow. While it is not obvious that the effect of increasing the thickness of the deflector on the flow field quality, and which may increase the requirements for the power source of the standard device. It is concluded that the elbow with a 135°turning angle and 2 pieces deflectors may be the optimal choice.
Rising Characteristics of a Methane Bubble under Different Conditions: A CFD Study
Authors: Mulbah Christian , Mao Ning , Zhang Wei , Yongphet Piyaphong 
Published: August 2020

Abstract
For a methane (CH4) bubble rising in liquid, knowledge of bubble rising characteristics is crucial for the comprehension of methane dissolution rate and the inter-phase mass transfer. Here, the investigation of a methane bubble was performed using the computational fluid dynamics (CFD) technique and the volume of fluid (VOF) two-phase model. The deionized water of 13 MPa and 5°C was used as the carrier of the rising bubble. Bubbles with diameters ranging from 3.0–6.0 mm were selected. The results show that the bubble instantaneous liquid velocity distribution and the wake structure manifest unique characteristics under such a high-pressure and low-temperature condition. The bubbly flow involves complicated vortex structures. Moreover, the bubble velocity is relatively low relative to those obtained under general conditions. A non-dimensional analysis of the bubble behavior indicates that the results obtained here deviate significantly from available results obtained under general conditions. The bubble diameter significantly influences the drag coefficient.
Numerical simulation of the gas–liquid two-phase flow in aeration tank based on different multiphase models
Authors: Guo Jinnan , Dong Liang , Liu Jiawei 
Published: August 2020

Abstract
In this paper, the Eulerian model and Mixture model are used to study the free surface, internal flow and mass transfer in the aeration tank. The two multiphase models affect the liquid velocity, internal flow and oxygen mass transfer coefficient (kLa) of the tank. Eulerian model than the Mixture model significantly higher simulates the liquid velocity near the impeller, and the range of the main longitudinal circulation vortex is smaller than Mixture model. The error between the simulated kLa of Eulerian model and the experimental value is smaller than Mixture model. The results show that the Eulerian model is more suitable for the simulation of the gas–liquid two-phase flow in the aeration tank.
Numerical Study on Gas Transport in Shale Kerogen with Adsorption Effect Using LBM
Authors: Peng Zhigao 
Published: August 2020

Abstract
Gas transport and storage mechanism in gas reservoirs with complex pore size distribution play a key role in gas production. In the nano-scale, during the process of density disturbance caused by depressurization development, notable output gas collides with the wall as they convey along the channel. The continuum assumption of fluid flow is therefore invalid, and taking the influence of particles to collide with solid walls into account is necessary. The effective viscosity and slip boundary conditions were introduced in the simulation. Meanwhile, because of the adsorption effect is one of the most important intrinsic properties of shale, the impact of surface adsorption on the solid wall by using Langmuir adsorption kinetics was also involved in our investigation. In this work, a unified LB model was developed for gas multiple transports and surface adsorption in nanopores. In the model, the double distribution function was employed for a coupled bulk flow and gas diffusion model. The model is valid within the range of the continuum regime to the transition regime and has been verified by the analytical solution and the results of some previously published works. The results show that (1) the driven force of the fluid, the combination coefficient of slippage and the Knudsen number of the flow have an impact on the adsorption rate, (2) adsorption effect only directly influence the local small region of the solid surface, and the induced concentration gradient makes the global concentration variation, (3) once acting the surface adsorption on the boundary, the flux falls more significant as Knudsen number increases.
Waste recycling as an aspect of the transition to a circular economy
Authors: Rumyantseva A , Rumyantseva E , Berezyuk M , Plastinina J 
Published: August 2020

Abstract
A necessary condition for a successful transition to a circular or closed economy is the creation of sufficient capacity for sorting and recycling of production and consumption waste. According to experts, annually more than 10 million tons of tires go out of use in the world, only in Russia every 4–5 years the increase in used tires will be about 2 million tons, which creates serious environmental and economic problems. This research is aimed at solving the problem of recycling accumulated and formed waste tires. The article provides a comparative analysis of tire recycling methods, proves the choice of pyrolysis method and estimates the environmental and economic efficiency of the project of a plant for processing used tires by pyrolysis.