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Special Issue on Network Pharmacology Modeling for Drug Discovery
Jing Tang
August 3, 2023 (v1)
Subject: Biosystems
During the process of drug discovery, many compounds have exhibited polypharmacological interactions with various biological entities [...]
Multi-Time Scale Economic Dispatch of Integrated Electricity and Natural Gas Systems with Flexibility Constraints Based on Chance-Constrained Programming
Peng Yang, Huilin Cheng, Zhenyu Liu, Jing Zhang, Liangce He, Yujie Liu, Zhigang Lu
August 3, 2023 (v1)
Keywords: chance-constrained programming, flexibility constraints, integrated energy system, multi-time scale, uncertainties
The connection between various energy types in the integrated power and natural gas system has grown stronger in recent years, as has the penetration rate of clean energy. Wind power generation volatility offers a considerable barrier to power system operation. This research provides a multi-time scale economic dispatch model with flexibility limitations to address this issue. Through chance-constrained programming, the equipment flexibility is described by probability functions and predetermined confidence levels in this model, and the generating cost and wind power consumption are improved through day-ahead and intra-day optimal scheduling. Finally, the effectiveness of the proposed model is verified by two case studies of integrated energy systems, where the results show that about 68.0−72.1% wind power curtailment can be effectively reduced while satisfying all load and system safety requirements.
Research Progress on Deep Eutectic Solvents and Recent Applications
Liting Mu, Jinshuang Gao, Qingyu Zhang, Fanyu Kong, Yu Zhang, Zhen Ma, Changhai Sun, Shaochun Lv
August 3, 2023 (v1)
Subject: Materials
Keywords: applications, deep eutectic solvents, properties
In this study, the classification, composition, preparation methods, and performance parameters of deep eutectic solvents (DESs) and their recent applications in natural product extraction, drug delivery systems, trace metal determination, nanomaterial synthesis, and electrochemistry are systematically summarised through the literature of recent decades, using DESs and applications as keywords. The hydrogen bond acceptors (HBA) of DESs are mainly quaternary ammonium salts (e.g., choline chloride) or amphoteric ions (e.g., betaine); the hydrogen bond donors (HBD) are mostly compounds such as urea, polyols, and sugars. Their melting points are related to hydrogen bonding, their polarities are higher than most ionic liquids, and their viscosities are generally in the range of 0.01−5 Pa·s. Compared with traditional organic solvents and conventional ionic liquids, DESs have higher solubility, with their ability to dissolve metal oxides and insoluble drugs, and have good biodegradability. DE... [more]
Determination of Soil Agricultural Aptitude for Sugar Cane Production in Vertisols with Machine Learning
Ofelia Landeta-Escamilla, Alejandro Alvarado-Lassman, Oscar Osvaldo Sandoval-González, José de Jesús Agustín Flores-Cuautle, Erik Samuel Rosas-Mendoza, Albino Martínez-Sibaja, Norma Alejandra Vallejo Cantú, Juan Manuel Méndez Contreras
August 3, 2023 (v1)
Keywords: land use, Machine Learning, soil agricultural aptitude, sugar cane, vertisols
Sugarcane is one of the main agro-industrial products consumed worldwide, and, therefore, the use of suitable soils is a key factor to maximize its production. As a result, the need to evaluate soil matrices, including many physical, chemical, and biological parameters, to determine the soil’s aptitude for growing food crops increases. Machine learning techniques were used to perform an in-depth analysis of the physicochemical indicators of vertisol-type soils used in sugarcane production. The importance of the relationship between each of the indicators was studied. Furthermore, and the main objective of the present work, was the determination of the minimum number of the most important physicochemical indicators necessary to evaluate the agricultural suitability of the soils, with a view to reducing the number of analyses in terms of physicochemical indicators required for the evaluation. The results obtained relating to the estimation of agricultural capability using different numbe... [more]
Fatigue Crack Propagation Behavior and Life Prediction of Welded Joints of SMA490BW Steel for Bogies
Xingyuan Xu, Liyang Xie, Song Zhou, Jinlan An, Yanqing Huang, Dongxia Li
August 3, 2023 (v1)
Keywords: crack propagation, FRANC 3D, life prediction, SMA490BW
In this paper, the precrack propagation behavior of an SMA490BW welded joint in the core zone and heat-affected zone was analyzed through experiments based on the FRANC 3D and ABAQUS cosimulation method, and life prediction of these cracks was also investigated. The results show that the experimental crack propagation path and crack propagation rate in the weld core zone and heat-affected zone agree well with the simulation results, with a small relative error. The life span of the prefabricated crack in the heat-affected zone was higher than that in the core zone. Furthermore, regarding the life prediction results for the two samples, the relative error obtained using FRANC 3D was about 5%, which was verified using the method of joint simulation of crack propagation behavior in the zone simulation and their life prediction with accurate feasibility.
A Quantitative Examination of the Efficiency of a Biogas-Based Cooling System in Rural Regions
Kenan Saka
August 3, 2023 (v1)
Keywords: animal species, biogas-powered cooling system, energy and exergy analysis, methane content, triple-effect absorption cooling system
This study investigates the efficiency of a biogas-powered cooling system through the utilization of energy and exergy calculations. Biogas, which can be generated and stored in small-scale plants as needed, serves as a viable fuel source for absorption cooling systems. The present research focuses on the biogas consumption of a triple-effect absorption cooling system specifically designed to supply a fixed cooling load of 100 kW under varying operational conditions. This study highlights the coefficient of performance and exergetic coefficient of performance values of the system, along with the exergy destruction rates of its individual components, at the optimal temperatures of operation. Furthermore, to determine necessary biogas consumption, this study explores the establishment of dedicated farms for various animal species, ensuring an adequate number of animals for biogas production. The findings reveal a coefficient of performance of 1.78 and an exergetic coefficient of performa... [more]
A Comprehensive Review of Organic Rankine Cycles
José C. Jiménez-García, Alexis Ruiz, Alejandro Pacheco-Reyes, Wilfrido Rivera
August 3, 2023 (v1)
Keywords: microturbines, organic Rankine cycles, Polygeneration, power production, waste heat recovery
It has been demonstrated that energy systems driven by conventional energy sources like fossil fuels are one of the main causes of climate change. Organic Rankine cycles can help to reduce that impact, as they can be operated by using the industrial waste heat of renewable energies. The present study presents a comprehensive bibliographic review of organic Rankine cycles. The study not only actualizes previous reviews that mainly focused on basic cycles operating on subcritical or supercritical conditions, but also includes the analysis of novel cycles such as two-stage and hybrid cycles and the used fluids. Recuperative and regenerative cycles are more efficient than reheated and basic single-stage cycles. The use of two-stage cycles makes it possible to achieve higher thermal efficiencies and net power outputs of up to 20% and 44%, respectively, compared with those obtained with single-stage cycles. Theoretical studies show that hybrid systems, including Brayton and organic Rankine c... [more]
Effects of Varied Forms of Arsenic Stress on Seedling Growth and Arsenic Distribution in Honeysuckle Plants
Xin Yuan, Juntong Zhou, Congnan Peng, Jiaqi Qiao, Shengqi Xia, Yilin Fan, Li Yao, Kailin Qi, Dongliang Chen, Zhiying Guo, Xiaolong Gan, Yaxuan Sun, Xueling Dai, Liangyu Lv, Yizhi Ji, Qing Huo
August 3, 2023 (v1)
Subject: Materials
Keywords: arsenic stress, honeysuckle, micro X-ray fluorescence, physiological indicators
At present, soil arsenic contamination is one of the prominent environmental problems. The arsenic concentration in honeysuckle exceeds the standard levels, thus affecting the quality of traditional Chinese medicine. In this study, the hydroponic method was employed to explore the effect of organic arsenic (dimethyl arsenic) and trivalent inorganic arsenic (NaAsO2) on the growth of honeysuckle plants. The study demonstrated that low concentrations of inorganic arsenic (10−20 mg/L) and 10−50 mg/L organic arsenic had a stimulating effect on the growth of honeysuckle plants. The activities of antioxidant enzymes (peroxidase and catalase) increased correspondingly. However, the antioxidant system in honeysuckle plants was damaged under high concentrations of inorganic arsenic (20−40 mg/L) and 50−70 mg/L organic arsenic. On exposure to 30 mg/L NaAsO2 or 50 mg/L dimethyl arsenic acid for 10 days, the activities of peroxidase and catalase, as well as the malondialdehyde content, increased wit... [more]
Numerical Study of the Effects of Roughness Coupled with Inclination on a Turbulent Flow around an Obstacle
Amine Brahimi, Redha Rebhi, Mounir Alliche
August 3, 2023 (v1)
Keywords: Computational Fluid Dynamics, forced convection, friction, Nusselt numbers, obstacle, roughness
In this study, we simulate the cooling of a microprocessor by thermal convection in three different shapes: a square, a trapezoidal, and a triangular shape. The latter is improved by a variety of types of roughness, including square roughness, triangular roughness Type 1, triangular roughness Type 2, and triangular roughness Type 3. The microprocessors are kept at a constant temperature, the air flow is constant, and the geometry is fixed. The physical phenomenon is simulated by the ANSYS software. The numerical results reported in this study cover the ranges of the obstacle’s angle of inclination, 0°≤θ≤45°, (square obstacles, θ=0°, trapezoidal obstacles, 0°<θ<45°, triangular obstacles, θ=45°) and Reynolds number, 2500≤Re≤10,000. The findings relate to streamlines, dynamic pressure (max), mean velocity, temperature field, mean Nusselt number (Nu/Nu0) profiles, local coefficient of friction (Cf/f0), mean coefficient of friction (f/f0) profiles, mean velocity field with roughness,... [more]
Development of an MCTS Model for Hydrogen Production Optimisation
Vitalijs Komasilovs, Aleksejs Zacepins, Armands Kviesis, Kaspars Ozols, Arturs Nikulins, Kaspars Sudars
August 3, 2023 (v1)
Keywords: control modes, cost optimisation, Hydrogen, Monte Carlo tree search, operation scheduling
Hydrogen has the potential to revolutionize the energy industry due to its clean-burning and versatile properties. It is the most abundant element in the universe and can be produced through a variety of methods, including electrolysis. The widespread adoption of hydrogen faces various challenges, including the high cost of production; thus, it is important to optimise the production processes. This research focuses on development of models for hydrogen production optimisation based on various external factors and parameters. Models based on electricity prices are developed and compared between different market situations. To run hydrogen production more effectively, it is required to use renewable energy sources for the production process. Adding the solar power component to the economic evaluation model outcome is more positive. The Monte Carlo tree search (MCTS) algorithm is adapted to effectively control the electrolysis process. MCTS schedule optimization was performed for a 24 h... [more]
Optimization of Cellulase-Assisted Extraction of Total Flavonoids from Equisetum via Response Surface Methodology Based on Antioxidant Activity
Hongmei Yin, Yuanli Zhang, Tingting Hu, Wen Li, Yang Deng, Xun Wang, Huaqiao Tang, Ling Zhao, Guangwen Yan
August 3, 2023 (v1)
Keywords: antioxidant capacity, cellulase-assisted extraction, Equisetum arvense L., flavonoid compounds, response surface methodology
Flavonoids are one of the most essential compounds in various plants. This study used the cellulase-assisted method to extract flavonoid-enriched antioxidants from Equisetum arvense L. (EAL). According to a three-factor and three-level central composite design, the response surface methodology was used to obtain the maximum total flavonoid yield, thereby providing the most potent antioxidant activity of EAL extracts. The results indicated that the optimal condition for the total flavonoid extraction was 0.52% (base substrate) enzyme concentration and enzymolysis for 50.58 min at 49.03 °C. The extraction rate of flavonoids from horsetail reached 4.88 mg/g under these optimal conditions. The yield was 51.23% higher than that from the traditional solid−liquid extraction method. The highest DPPH-scavenging ability of the extracts obtained under 0.50% enzyme concentration and enzymolysis for 49.41 min at 46.59 °C was 77.36%. HPLC results revealed that the antioxidant substances had diverse... [more]
Numerical Simulation of Pore Pressure Change Caused by Hydrocarbon Generation in Chezhen Sag and Its Influence on Hydrocarbon Accumulation
Mingwen Wang, Gang Luo, Feng Qin, Zonghu Liao, Shuhong Zhou, Nianfa Yang
August 3, 2023 (v1)
Subject: Other
Keywords: Chezhen Sag, hydrocarbon downward migration, numerical simulation, overpressure, upper source-lower reservoir
The pore fluid pressure is important for the generation, migration, and accumulation of hydrocarbons. The Chezhen Sag region in the Bohai Bay Basin is typically characterized by pore fluid overpressure, which is the difference between the pore fluid pressure and the hydrostatic pore pressure. The formation mechanisms of pore overpressure and the accumulation regularity of the “upper source-lower reservoir” type in this region remain unknown. In order to investigate these problems, based on the existing seismic, logging data, and regional tectonic stress environment, we established a two-dimensional finite element model to simulate the fluid−solid coupling processes in the Chegu 25 block of the Chezhen depression. We calculated the abnormal overpressure generated at the source rock during hydrocarbon generation and the processes of hydrocarbon migration and accumulation along the faults and analyzed the dynamic conditions of the hydrocarbon downward accumulation. The results showed that... [more]
Reaction−Diffusion Process for Hydrogels with a Tailored Layer Structure
Yongliang Wang, Yaxin Xu, Yunfei Wang, Baoqiang Li, Chunfeng Wang, Zhidong Han, Ling Weng
August 3, 2023 (v1)
Subject: Materials
Keywords: chitosan, enhanced mechanical property, reaction–diffusion
The architecture of hydrogel composites results in not only synergistic property enhancement but also superior functionality. The reaction−diffusion (RD) process is acommon phenomenon throughout nature which induced ordered structure on a length scale from microscopic to macroscopic. Different from commonly used inorganic salts or oppositely charged nanoparticles for the RD process, a modified RD process was used for layered chitosan hydrogel (L-CH) and layered magnetic chitosan hydrogel (L-MCH). During the modified RD process reported in this paper, the protonated chitosan (CS-NH3+) with iron ions (Fe3+ and Fe2+) was used as an inner-reactant and hydroxide ion (-OH−) was used as an out-reactant. The protonated chitosan (CS-NH3+) not only played the role of an inner-reactant but also the reaction medium which controlled the diffusion behavior of the out-reactant (-OH−). A series of ordered layers were constructed and the ordered layers were parallel with the longitudinal axis. The laye... [more]
CFD Modeling of Phase Change during the Flashing-Induced Instability in a Natural Circulation Circuit
Yixiang Liao, Dirk Lucas
August 3, 2023 (v1)
Keywords: CFD modeling, flashing-induced instability, thermal and mechanical non-equilibrium, thermal phase change model
Flashing-induced instability (FII) has a significant impact on the safe operation of a natural circulation circuit, a phenomenon frequently encountered in the cooling systems of advanced light water reactors. While one-dimensional system codes are commonly used for the engineering design and safety analysis of FII, there is a strong academic interest in understanding the underlying physical mechanisms. To address this, high-resolution computational fluid dynamics (CFD) simulations serve as a valuable tool. However, the current state of CFD modeling for two-phase flows with phase change, which are particularly highly transient fluctuating flashing flows, is still in its early stages of development. In this study, we establish a CFD model that focuses on interphase heat transfer to analyze the phase change during FII. By incorporating experimental data from the literature, we investigate the transient flow field and thermodynamic behavior in the riser of the GENEVA test facility. The stu... [more]
Effect of Mold Flow Channel Parameters on Gas-Assisted Extrusion of Medical Microtubules
Xiaohui Zhang, Xingyuan Huang, Bin Liu, Shiyu Jiang, Shaoyi Ren
August 3, 2023 (v1)
Keywords: flow channel parameters, forming quality, gas-assisted extrusion, medical microtubule, numerical simulation
Due to the complexity of mold flow channel parameters, they have a significant impact on medical microtubule forming quality during the gas-assisted extrusion process. In this paper, the influence mechanism of mold flow channel parameters on medical microtubule forming quality is investigated. First, the multiphase flow model of the medical microtubule gas-assisted extrusion process is established. Then, the numerical solution of medical microtubule extrusion is presented based on Polyflow finite element software. Further, the medical microtubule size, morphology, velocity, pressure, and first normal stress difference under different mold flow channel parameters are compared and analyzed. Finally, the experimental platform for gas-assisted extrusion is built, and the correctness of the numerical simulation is verified by the extrusion experiment. The simulation and experimental results show that under the 15−5 condition, the inner radius, outer radius, and wall thickness of the microtu... [more]
Research Progress and Development Trend of Prognostics and Health Management Key Technologies for Equipment Diesel Engine
Zichang Liu, Cuixuan Zhang, Enzhi Dong, Rongcai Wang, Siyu Li, Yueming Han
August 3, 2023 (v1)
Keywords: data acquisition, data processing, diesel engine, fault diagnosis, health status assessment, prognostics and health management, reliability
The diesel engine, as the main power source of equipment, faces practical problems in the maintenance process, such as difficulty in fault location and a lack of preventive maintenance techniques. Currently, breakdown maintenance and cyclical preventive maintenance are the main means of maintenance support after a diesel engine failure, but these methods require professional maintenance personnel to carry out manual fault diagnosis, which is time-consuming. Prognostics and health management (PHM), as a new technology in the field of equipment maintenance support, has significant advantages in improving equipment reliability and safety, enhancing equipment maintenance support capability, and reducing maintenance support costs. In view of this, when introducing PHM into diesel engine maintenance support, the research progress and development trend of the key technologies of PHM for diesel engines are carried out with the objective of achieving precise maintenance and scientific managemen... [more]
Non-Carcinogenic Risk Assessment for Heavy Metals in the Soil and Rice in the Vicinity of Dabaoshan Mine, South China
Huarong Zhao, Kangming Shi, Jianqiao Qin, Zikang Ren, Guoliang Yang
August 3, 2023 (v1)
Keywords: Dabaoshan mine, hazard quotient, heavy metal, normal QQ plot, paddy soil, rice
Heavy-metal pollution has attracted wide attention in recent years. The problem of heavy-metal pollution in the vicinity of the Dabaoshan mine, the largest polymetallic mine in South China, has attracted widespread attention. In this study, 38 samples of rice and paddy soil near the Dabaoshan mine were collected. The physical and chemical properties of the soil, including Cu, Cd, Zn, Pb, and Ni levels in the soil and rice, were analyzed. The heavy-metal baseline in paddy soil was analyzed by a normal Q−Q plot. The bioaccumulation factor of the rice was calculated. The non-carcinogenic risk of heavy metals was evaluated by calculating the hazard quotient (HQ). Threshold values of Cu, Cd, Zn, Pb, and Ni were 35.01, 0.51, 70.94, 59.78, and 16.34 mg/kg, respectively. The threshold values of Cu, Zn, and Pb were higher than the background value and lower than the secondary value of China’s soil environmental quality standard. The threshold value of Cd was higher than both the background valu... [more]
Torrefaction under Different Reaction Atmospheres to Improve the Fuel Properties of Wheat Straw
Ricardo Torres Ramos, Benjamín Valdez Salas, Gisela Montero Alpírez, Marcos A. Coronado Ortega, Mario A. Curiel Álvarez, Olivia Tzintzun Camacho, Mary Triny Beleño Cabarcas
August 3, 2023 (v1)
Keywords: agricultural residues, Biofuels, non-oxidative torrefaction, oxidative torrefaction, response surface methodology (RSM)
This study aimed to produce biochar with an energy value in the range of sub-bituminous carbon by investigating the effect of oxidative and non-oxidative torrefaction on the torrefaction yield and fuel properties of wheat straw. Three independent variables were considered at different levels: temperature (230, 255, 280, 305 °C), residence time (20, 40, 60 min), and reaction atmosphere (0, 3, 6 vol% O2; N2 balance); and three dependent variables: mass yield, energy yield, and percentage increase in higher heating value (HHV). The results showed that it is possible to produce a sub-bituminous carbon type C biochar using oxidative torrefaction, significantly reducing time and temperature compared with non-oxidative torrefaction. The optimum torrefaction conditions were 287 °C−20 min−6.0% O2, which increased the HHV of wheat straw from 13.86 to 19.41 MJ kg−1. The mass and energy yields were 44.11 and 61.78%, respectively. The physicochemical and fuel properties of the obtained biochar were... [more]
Vibration Scale Model of a Converter Transformer Based on the Finite Element and Similarity Principle and Its Preparation
Hao Wang, Li Zhang, Youliang Sun, Liang Zou
August 3, 2023 (v1)
Keywords: converter transformer, finite element, prototype preparation, similarity model, vibration
A similarity criterion suitable for studying the vibration characteristics of converter transformers is proposed based on comprehensive consideration of geometric dimensions, electric field, magnetic field, force field, sound field, and coupling field interface interactions. By comparing the magnetic field, stress, displacement, sound field distribution, and vibration characteristics of the scale model of the converter transformer with the initial model, the reliability of the similarity criterion was determined. Based on the vibration similarity criterion of the converter transformer, a prototype of the proportional model was designed and manufactured, and vibration signals under no-load and load conditions were tested. These signals correspond to the vibration signals of the iron core and winding in the finite element model, respectively. Through comparative analysis, the reliability of the prototype and the vibration similarity model of the converter transformer has been proven, whi... [more]
A Cost/Benefit and Flexibility Evaluation Framework for Additive Technologies in Strategic Factory Planning
Angela Luft, Sebastian Bremen, Nils Luft
August 3, 2023 (v1)
Keywords: additive manufacturing, factory planning, manufacturing flexibility, mix flexibility, production planning, volume flexibility
There is a growing demand for more flexibility in manufacturing to counter the volatility and unpredictability of the markets and provide more individualization for customers. However, the design and implementation of flexibility within manufacturing systems are costly and only economically viable if applicable to actual demand fluctuations. To this end, companies are considering additive manufacturing (AM) to make production more flexible. This paper develops a conceptual model for the impact quantification of AM on volume and mix flexibility within production systems in the early stages of the factory-planning process. Together with the model, an application guideline is presented to help planners with the flexibility quantification and the factory design process. Following the development of the model and guideline, a case study is presented to indicate the potential impact additive technologies can have on manufacturing flexibility Within the case study, various scenarios with diff... [more]
Stability Analysis and Nonlinear Chatter Prediction for Grinding a Slender Cylindrical Part
Tianyi Sun, Yao Yan
August 3, 2023 (v1)
Keywords: almost-asynchronized nonlinear chatter, continuation algorithm, plunge grinding slender parts, time-delayed regenerative chatter
A cylindrical plunge grinding process was modeled to investigate nonlinear regenerative chatter vibration. The rotating workpiece was a slender Euler−Bernoulli beam, and the grinding wheel was a rigid body moving towards the workpiece at a very low feed speed. A numerical method was proposed to provide the critical boundaries for chatter-free grinding. It was demonstrated that the intersection set surrounded by these critical boundaries was the chatter-free region for the considered parameters. When these parameters were outside of the chatter-free region, the stable grinding process underwent a supercritical Hopf bifurcation, resulting in the loss of the chatter-free behavior and the emergence of periodic chatter motions. Then, the periodic motions of both the grinding wheel and the workpiece were predicted analytically using the method of multiple scales, showing the effect of the regenerative force on the grinding process. We demonstrated that the analytical prediction was valid sin... [more]
Influence of Dielectric Barrier Discharge Plasma Treatment on Corn Starch Properties
Mayara L. Goiana, Fabiano A. N. Fernandes
August 3, 2023 (v1)
Subject: Materials
Keywords: amylopectin, amylose, cold plasma, corn starch
This study evaluated the effects of dielectric barrier discharge (DBD) plasma technology on some physicochemical and structural properties of corn starch. Amylose content, solubility, water absorption index, turbidity, structural relationships, and surface morphology were measured at 100, 200, and 300 Hz excitation frequencies and at 10 and 20 min exposure times. The plasma treatment at 200 Hz and 20 min promoted the most significant modifications in amylose content, solubility, the water absorption index, and surface morphology. Turbidity did not change significantly. The surface of the granule became smoother with the presence of pores. Slight changes were observed in the ordered structure of starch. Plasma changed several physicochemical properties, significantly decreasing the amylose to amylopectin ratio. Plasma treatment at 200 Hz is recommended to increase the amylopectin content in starches.
Experimental Study on Wide-Graded Soil Transport in Unsteady Flow
Tianlong Zhao, Tingsen Ma, Changjing Fu, Chuan Zhang
August 3, 2023 (v1)
Subject: Materials
Keywords: erosion mechanism, overtopping flow, unsteady flow, wide gradation
A special study on the interaction mechanism between flow and soil is of great significance for revealing the macro breaching mechanism of barrier dams. To study the scouring characteristics of wide-graded sediment under different flow conditions, flume scour tests were conducted regarding the grading curve of dam material and the discharge process of the Tangjiashan barrier dam. The results show that: (1) The scouring process of narrow-graded or uniform sediments is the formation and movement of the sand wave, while the scouring mode of wide-graded sediment is mainly the formation, expansion, and movement of the scouring pit. (2) Under the condition of weak unsteady flow, the surrounding and shielding effect of coarse particles on fine particles is obvious, and the erosion resistance of the material is strong. However, under the condition of strong unsteady flow, the erosion resistance is weak. (3) The erosion of wide-graded sediment is mainly caused by slope angle collapse at the ini... [more]
A Novel Inner Wall Coating-Insulated Oil Pipeline for Scale and Wax Prevention
Jing Cao, Wenhai Ma, Weiming Huang, Zhanfei Su, Yunbo Zhu, Jianjun Wang
August 3, 2023 (v1)
Subject: Materials
Keywords: coating material, numerical model, oil pipeline, thermal insulation performance
During the production of deep oil and gas, scaling, waxing, hydrate ice plugging and other problems easily occur. To solve these problems, reducing the temperature loss of oil pipelines is a feasible method. In order to protect the outer wall coating from being damaged and losing its thermal insulation performance, this paper proposes a developed technology for a novel inner wall coating-insulated oil pipeline. A new temperature-resistant and heat-insulating material aerogel was optimized and developed, and it has an extremely low thermal conductivity of less than 0.055 W/m·K. The influence of different coating processes on the thermal insulation coefficient was analyzed, and a novel inner wall coating-insulated oil pipeline was developed. A testing and evaluation platform for its thermal insulation effect was built, and a finite element model was established to analyze the temperature field distribution. When the thickness of the inner coating was 0.5 mm, the thermal insulation effect... [more]
Development of a Lux Meter for the Identification of Liquids in Post-Consumer Polyethylene Terephthalate Bottles for Collection Centers in Mexico
L. A. Ángeles-Hurtado, Juvenal Rodríguez-Reséndiz, Hilda Romero Zepeda, Hugo Torres-Salinas, José R. García-Martínez, Silvia Patricia Salas-Aguilar
August 3, 2023 (v1)
Keywords: ANOVA, automation, classification, illuminance, lux meter, Machine Learning, municipal solid waste, PET, recycling
This article aims to enhance technological advancements in the classification of polyethylene terephthalate (PET) bottle plastic, positively impacting sustainable development and providing effective solutions for collection centers (CC) in Mexico. Three experimental designs and machine learning tools for data processing were developed. The experiments considered three factors: bottle size, liquid volume, and bottle labels. The first experiment focused on determining the sensor distance from post-consumer PET bottles. The second experiment aimed to evaluate the sensor’s detection ability with varying liquid levels, while the third experiment assessed its detection capability for bottle labels. A digital lux meter integrated with a microcontroller was developed to monitor illuminance in post-consumer PET bottles containing liquid as they moved through a conveyor belt at an average rate of three bottles per second. The implemented methodology successfully detected liquids inside transpare... [more]
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