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Records with Type: Published Article
3101. LAPSE:2023.36419
Interfacial Electron Transfer and Synergistic Effects on NiCo(CA)@M Microbars That Boost the Alkaline Oxygen Evolution Reaction
August 2, 2023 (v1)
Subject: Materials
Keywords: composite, electrocatalysis, metal-organic frameworks, oxygen evolution reaction, water splitting
The development of oxygen evolution reaction electrocatalysts with a low cost, high activity, and strong stability is of great significance to the breakthrough of energy conversion technology. Herein, a composite material (NiCo(CA)@M) was obtained by growing nickel-cobalt nanoparticles on MIL-88A in situ by a simple two-step solvent thermal method. The results show that NiCo(CA)@M composite has rich active sites, and the formation of the composite induces charge redistribution between NiCo(CA) and MIL-88A, effectively reducing the reaction energy barrier, while growth in situ was conducive to the improvement of material stability. Impressively, the NiCo(CA)@M catalyst achieved a current density of 10 mA cm−2 in alkaline electrolyte required an overpotential of only 270 mV and the Tafel slope was 69 mV dec−1. At the same time, the NiCo(CA)@M catalyst had excellent stability at a current density of 10 mA cm−2, and after the 16 h i-t test, the catalyst still had 91.1% current density rete... [more]
3102. LAPSE:2023.36418
Distribution Characteristics of Heavy Metals in Different Particle Size Fractions of Chinese Paddy Soil Aggregates
August 2, 2023 (v1)
Subject: Environment
Keywords: heavy metals, leachability, paddy soil, particle size fraction, soil aggregates
In recent years, the migration and transformation of heavy metals (HMs) in soil has become a hot issue. Soil particle size has an important effect on the environmental behavior of HMs in soil. The distribution of HMs in soil is strongly affected by the size of a soil aggregate. In this study, paddy samples in both cultivated and uncultivated soils were collected from Anhui Province, China. The soils were sieved into six particle size fractions (diameters of >4000, 4000−2000, 2000−1000, 1000−250, 250−53, and 4000 μm particles. Moreover, the concentrations of Cd, Cr, Pb, and As were elevated in cultivated paddy soils compared to uncultivated soils. The accumulation of HMs in all paddy soils increased with decreasing particle size. Although the smallest particle size fractions accounted for only 5.65−17.28%, they provided the highest distribution factor (DF) of Cr (1.35), As (1.25), Cd (1.28), and Pb (1.38). The highest contributions of HMs came from the coarser fractions (>2000 μm); howe... [more]
3103. LAPSE:2023.36417
Intelligent Temperature Control of a Stretch Blow Molding Machine Using Deep Reinforcement Learning
August 2, 2023 (v1)
Subject: Modelling and Simulations
Keywords: deep learning, intelligent temperature control, reinforcement learning, stretch blow molding
Stretch blow molding serves as the primary technique employed in the production of polyethylene terephthalate (PET) bottles. Typically, a stretch blow molding machine consists of various components, including a preform infeed system, transfer system, heating system, molding system, bottle discharge system, etc. Of particular significance is the temperature control within the heating system, which significantly influences the quality of PET bottles, especially when confronted with environmental temperature changes between morning and evening during certain seasons. The on-site operators of the stretch blow molding machine often need to adjust the infrared heating lamps in the heating system several times. The adjustment process heavily relies on the personnel’s experience, causing a production challenge for bottle manufacturers. Therefore, this paper takes the heating system of the stretch blow molding machine as the object and uses the deep reinforcement learning method to develop an i... [more]
3104. LAPSE:2023.36416
Application of Improved Artificial Immune System Algorithm Based on Applied Mathematics for Optimization of Manpower Allocation in Construction Engineering
August 2, 2023 (v1)
Subject: Energy Systems
Keywords: construction engineering, human resource allocation, mathematical model, NAIS algorithm
The outbreak of the COVID-19 pandemic has led construction companies to prioritize the intelligent and optimal scheduling of human resources in construction projects to reduce costs. This study addresses the problem of heterogeneity in human resource scheduling in construction projects, presents a mathematical model with generic human resources as an example, proposes an improved artificial immune system (NAIS) algorithm to solve the problem, and verifies its effectiveness. Experimental results show that the NAIS algorithm achieves the optimal duration of 9 days in just 2 s using the Matrix Laboratory (MATLAB), which is significantly faster than mathematical optimization technique software (CPLEX), thus confirming the feasibility of the NAIS algorithm. Additionally, the average PD values for the NAIS algorithm, calculated for different worker counts, skills, and the number of tasks, were lower compared to the comparison algorithm. Overall, the NAIS algorithm effectively addresses the h... [more]
3105. LAPSE:2023.36415
Influence of Rapeseed Oil on Extruded Plant-Based Meat Analogues: Assessing Mechanical and Rheological Properties
August 2, 2023 (v1)
Subject: Materials
Keywords: extrusion, meat analogues, oil, pea protein, soy protein
Successfully replacing meat with plant-based options will require not only replicating the texture of muscular fibres, but also imitating the taste, aroma, and juiciness of meat as closely and realistically as possible. This study examines the impact of rapeseed oil on the textural properties of meat analogues. Pea protein and soy protein are chosen as model systems to assess the effect of rapeseed oil. Optical, mechanical, and rheological characterisation tests are conducted to investigate the oil droplet distribution, the gel strength, Young’s modulus, and the length of the LVE region. The hypothesis is that oil droplets will act as active fillers in the protein matrix, and thus, diminish the strength of the protein gel network. The results of this study show that rapeseed oil droplets act as inactive fillers, as they are not bound to both examined protein matrices. Soy protein extrudates display minimal changes, while pea protein extrudates are significantly affected by the addition... [more]
3106. LAPSE:2023.36414
Analysis Method of Full-Scale Pore Distribution Based on MICP, CT Scanning, NMR, and Cast Thin Section Imaging—A Case Study of Paleogene Sandstone in Xihu Sag, East China Sea Basin
August 2, 2023 (v1)
Subject: Process Control
Keywords: CT cylinder model, CT scan, full-scale pore distribution, mercury withdrawal, NMR, tortuosity index
Using different experimental methods, the pore radius ranges vary greatly, and most scholars use a single experiment to study pore structure, which is rarely consistent with reality. Moreover, the numerical models used in different experiments vary and cannot be directly compared. This article uniformly revised all experimental data into a cylinder model. Quantitative analysis of the full-scale pore distribution is established by mercury withdrawal−CT data, and semi-quantitative distribution is obtained by mercury−NMR−cast thin section imaging. In this paper, we introduce the tortuosity index (τ) to convert the CT ball-and-stick model into a cylinder model, and the pore shape factor (η) of the cast is used to convert the plane model into the cylinder model; the mercury withdrawal data is applied to void the influence of narrow throat cavities, and the NMR pore radius distribution is obtained using the mercury-T2 calibration method. Studies have shown that the thickness of bound water i... [more]
3107. LAPSE:2023.36413
Development of a Novel Hydrodynamic Sequencing Batch Reactor for Landfill Leachate Treatment by Shortcut Biological Nitrogen Removal
August 2, 2023 (v1)
Subject: Food & Agricultural Processes
Keywords: hydrodynamic model, nitrite accumulation, nitrogen removal, oxygen transfer rate, wastewater treatment
This study introduced an alternative shortcut biological nitrogen removal (SBNR) process for landfill leachate treatment by developing a novel hydrodynamic sequencing batch reactor (H-SBR). The reactor could enhance the oxygen transfer rate (OTR) and nitrite accumulation ratio (NAR) by modifying internal hydrodynamic turbulence intensity. The average chemical oxygen demand (COD) and total nitrogen (TN) concentrations introduced into the reactor were 660 and 250 mg L−1, respectively, and the average removal efficiencies were 93% (COD) and 96% (TN). The effect of geometric parameters on oxygen transfer was estimated by performing a hydrodynamic model and a nonlinear least square analysis. After correcting the constants (α and β) of mass transfer coefficients (KLa) to values of 0.7361 and 1.2639, the model data fit the experiment well with an R-squared value of 0.99. The OTR improved by up to 30%, and hence, increased the NAR by up to 20% with a reduction of about 0.5 kg N kW−1 for power... [more]
3108. LAPSE:2023.36412
Design of Intelligent Nonlinear H2/H∞ Robust Control Strategy of Diesel Generator-Based CPSOGSA Optimization Algorithm
August 2, 2023 (v1)
Subject: Energy Systems
Keywords: diesel generator, intelligent optimization, robust control, speed and excitation control
In today’s human society, diesel generators (DGs) are widely applied in the human energy and electricity supply system due to its technical, operational, and economic advantages. This paper proposes an intelligent nonlinear H2/H∞ robust controller based on the chaos particle swarm gravity search optimization algorithm (CPSOGSA), which controls the speed and excitation of a DG. In this method, firstly, establish the nonlinear mathematical model of the DG, and then design the nonlinear H2/H∞ robust controller based on this. The direct feedback linearization and the H2/H∞ robust control theory are combined and applied. Based on the design of the integrated controller for DG speed and excitation, the system’s performance requirements are transformed into a standard robust H2/H∞ control problem. The parameters of the proposed solution controller are optimized by using the proposed CPSOGSA. The introduction of CPSOGSA completes the design of an intelligent nonlinear H2/H∞ robust controller f... [more]
3109. LAPSE:2023.36411
Dynamical Simulation, Sensitivity, and Productivity Analysis of a Light-Photoacclimation Model for Microalgae-Based Carbohydrate Production in Continuous Photobioreactors
August 2, 2023 (v1)
Subject: Biosystems
Keywords: carbohydrate pool, dynamic simulation, microalgae, photoacclimation model, photobioreactors, productivity, sensitivity
The world’s human population is increasing as is the demand for new sustainable sources of energy. Accordingly, microalgae-based carbohydrates for biofuel production are being considered as an alternative source of raw materials for producing biofuels. Microalgae grow in photobioreactors under constantly changing conditions. Models improve our understanding of microalgae growth. In this paper, a photoacclimated model for continuous microalgae cultures in photobioreactors was used to study the time-varying behavior and sensitivity of solutions under optimal productivity conditions. From the perspective of dynamic simulation in this work, light intensity was found to play an influential role in modifying metabolic pathways as a cell stressor. Enhancing carbohydrate productivity by combining nutritional deficiency and light intensity regulation modeling strategies could be helpful to optimize the process for the highest yield in large-scale cultivation systems. Under the proposed simulati... [more]
3110. LAPSE:2023.36410
Study on the Coalescence-Induced Jumping of Droplets with Different Radii on Superhydrophobic Surface
August 2, 2023 (v1)
Subject: Modelling and Simulations
Keywords: coalescence-induced jumping, critical radius ratio, molecular dynamics simulations, superhydrophobic surfaces, unequal radii
The phenomenon of droplet coalescence and jumping has received increasing attention due to its potential applications in the fields of condensation heat transfer and surface self-cleaning. Basic research on the process and mechanism of coalescence-induced droplet jumping has been carried out, and some universal laws have been established. However, it is found that the focus of these studies is based on two identical droplets, and the coalescence-induced jumping with different radii is rarely investigated, which is commonly encountered in nature. Therefore, it is essential to proceed with the research of coalescence and jumping of droplets with unequal radii. In this paper, molecular dynamics (MD) simulations are performed to reveal the effects of radius ratio and radius of small droplets on jumping velocity. The results show that as the increasing of radius ratio with an unchanged small droplet radius of 8.1 nm, the jumping velocity increases then decreases, which indicates there is an... [more]
3111. LAPSE:2023.36409
Effects of Surfactant Characteristics on Fuel Properties of Emulsions of Alternative Engine Fuel through the Phase Inversion Method
August 2, 2023 (v1)
Subject: Energy Systems
Keywords: emulsion fuel, fast cooling process, kinematic viscosity, mean droplet size, phase inversion temperature, surfactant characteristics
Emulsions that mix two or more immiscible phases are broadly applied in pharmaceutics, chemistry, and industries. The phase inversion temperature (PIT) method is an emulsifying approach to preparing an emulsion with low energy consumption and cheap equipment. The effects of surfactant characteristics and processes of cooling or heating on the fuel properties of emulsions composed of silicone oil by the emulsifying method, such as mean droplet sizes of the de-ionized water phase, were considered herein. The application of the silicone oil emulsion as engine fuel was first evaluated. The results show that the emulsions added with the polyol surfactant mixture appeared to have a larger mean water-droplet size, a larger number of dispersed water droplets, a wider range of dispersed-water sizes, and lower kinematic viscosity than those with Brij 30 surfactant. Increasing the surfactant concentration of either Tween 20 mixed with Span 80 or Brij 30 surfactant increased kinematic viscosity an... [more]
3112. LAPSE:2023.36408
Application of Micro-Seismic Monitoring in Post-Fracturing Evaluation of Shale Gas: A Case Study of Well X from Puguang Area, China
August 2, 2023 (v1)
Subject: Energy Systems
Keywords: fracture network, micro-seismic monitoring, multi-stage fracturing, shale gas
Multi-stage fracturing of horizontal wells is an indispensable technology to create complex fracture networks, which can unlock production potential and enable commercial productivity for shale gas with low porosity and permeability. Real-time monitoring of fracture networks is essential for adjusting key parameters, mitigating fracturing risks, and achieving optimal fracturing effects. Micro-seismic monitoring technology accurately captures and describes the development of fracture networks by detecting micro-seismic waves generated through rock ruptures, providing valuable insights into the evaluation of post-fracturing. In this study, we first introduced the basic parameters of well X that were obtained by laboratory experiments and logging interpretation, including porosity, gas-bearing properties, mineral composition, rock mechanics, and crustal stress. Then, the hydraulic fracturing scheme was designed on the basis of the geological engineering characteristics of well X. Finally,... [more]
3113. LAPSE:2023.36407
Experimental Study on the Damage and Failure Characteristics of High-Temperature Granite after Liquid-Nitrogen Cooling
August 2, 2023 (v1)
Subject: Materials
Keywords: damage, high-temperature granite, hot dry rock, liquid-nitrogen cooling
To analyze the influence of liquid-nitrogen cooling on the damage and failure of high-temperature granite, granite samples were heated to 150~600 °C for natural cooling and liquid-nitrogen cooling treatment. Brazilian splitting tests were carried out as the samples returned to room temperature, and basic tensile and energy evolution parameters were obtained. Acoustic emission signal parameters during loading were recorded. The experimental results showed that the heating process caused damage to the granite samples, and liquid-nitrogen cooling further increased the degree of damage. Specifically, the ultrasonic velocity of liquid-nitrogen-cooled samples was lower than that of naturally cooled samples at each heating temperature. With an increase in heating temperature, the AE ring-down counts of liquid-nitrogen-cooled samples were higher than that of naturally cooled samples. At the same heating temperature, the dissipated energy of naturally cooled samples was greater than that of liq... [more]
3114. LAPSE:2023.36406
The Investigation of Two-Phase Expansion Performance with Indicator Diagram in a Twin-Screw Expander
July 13, 2023 (v1)
Subject: Energy Systems
Keywords: low grade heat, twin-screw expander, two-phase expansion, waste heat recovery
Volumetric expanders are proven to be more suitable for small-scale waste heat recovery applications because of their simplicity, reliability, lower rotational speed and lower cost. Unlike turbines, volumetric expanders can work in the two-phase fluid state, which broadens their application fields. To investigate the two-phase performance of volumetric expanders, a specific twin-screw expander was chosen and modeled. The leakage loss and the suction pressure loss were primary concerns in this research. The two-phase expansion process in the expander is presented in detail using the developed mathematical model with an indicator diagram. The influence of several factors, including inlet vapor quality, rotational speed and intake pressure, are investigated. The influence mechanism of the vapor phase and the liquid phase on expander performance is clarified. In brief, this paper presents an illustrative understanding of the two-phase expansion process in twin-screw expanders.
3115. LAPSE:2023.36405
Numerical Investigations of Heat Transfer and Fluid Flow Characteristics in Microchannels with Bionic Fish-Shaped Ribs
July 13, 2023 (v1)
Subject: Process Design
Keywords: bionic ribs arrangement, heat transfer, microchannel, numerical simulation, thermal boundary layers
Microchannel cooling technology is an effective method to solve local thermal stacking. In this paper, four innovative microchannels with bionic fish-shaped rib arrangements (CM-O, CM-R, CM-H, and CM-G) are designed by imitating geese and fish clusters. The heat transfer and flow characteristics of the microchannels are simulated numerically at different Reynold’s numbers (Re = 200 − 1600). The liquid water temperature and flow field in the four innovative microchannels with bionic ribs are analyzed. The results show that the ribs’ arrangement has an influence on the thermal performance of microchannels. Compared to the smooth microchannel (CM), the of the Nu microchannels with the bionic fish-shaped ribs increases by 33.00−53.26% while the fave increases by 28.63−34.93% at Re = 1200. The vortices around the ribs are clearly observed which improves the temperature gradient. The performance evaluation criterion (PEC) of CM-H is higher than that of the others. This indicates that the rib... [more]
3116. LAPSE:2023.36404
Synthesis and Biological Evaluation of α-Tocopherol Derivatives as Potential Anticancer Agents
July 13, 2023 (v1)
Subject: Biosystems
Keywords: apoptosis, cancer, mitocans, vitamin E derivatives, α-tocopheryl succinate (α-TS), α-tocopheryloxyacetic acid (α-TEA)
α-Tocopheryl succinate (α-TS) and α-tocopheryloxyacetic acid (α-TEA) are potent inducers of apoptosis in cancer cells and efficient suppressors of tumors in experimental model cancer cell lines. They exhibit selective cytotoxicity against tumor cells and very limited or no toxicity toward nonmalignant cells. In the present work, a series of new α-tocopherol derivatives were synthesized as analogs of α-TS and α-TEA. The cytotoxic activity of obtained compounds was tested using three human cancer cell lines, including chronic lymphoblastic leukemia (CEM), breast adenocarcinoma (MCF7), cervical adenocarcinoma (HeLa), and normal human fibroblasts (BJ). The introduction of an alkyl substituent into the ether-linked acetic acid moiety in α-TEA increased anticancer activity. α-Tocopheryloxy-2-methylpropanoic acid with two additional geminal methyl groups was more active against CEM cells compared to α-TEA and non-toxic to normal cells. In order to acquire a deeper understanding of the biologi... [more]
3117. LAPSE:2023.36403
Observer-Based Control of Inductive Wireless Power Transfer System Using Genetic Algorithm
July 13, 2023 (v1)
Subject: Electricity & Electrical Devices
Keywords: eigenstructure assignment, Genetic Algorithm, linear quadratic regulator, wireless power transfer
In this paper, we studied the feedback stabilization of an inductive power transfer system based on available output measurement. The proposed controller relies on a full-order state observer in order to estimate the unmeasured state. The control design problem is challenging due to the large dimension of the closed-loop system, which requires too many tuning parameters to be determined when conventional control methods are employed. To solve this issue, we propose an LQR methodology based on a genetic algorithm such that the weighing coefficients of the cost function matrices can be automatically computed in an optimized manner. The proposed approach combines the method of eigenstructure assignment and the LQR technique in order to design both the controller and the observer gain matrices. The design methodology provides a systematic way to compute the parameters of the LQR technique for a wireless power transfer system in an optimized manner, which can be a useful design tool for man... [more]
3118. LAPSE:2023.36402
Thermo-Hydraulic Management System Employing Single-Phase Water Flow through Microchannels with Micro-Inserts Added Aiming for Performance Improvement
July 13, 2023 (v1)
Subject: Energy Systems
Keywords: friction factor, heat transfer performance, micro-inserts, microchannel, pressure drop, thermal performance factor
A microchannel heat exchanger effectively evacuates heat from a confined space. This paper attempts to gain insight into the combinatorial repercussions of simultaneously coupling two factors that affect a microchannel’s performance, of which channel size and micro-insert complexity are the two main contributors. With water as the working fluid, an ANSYS-based numerical analysis was carried out for two distinct channel sizes, 1 and 2 mm, both with and without micro-inserts. The Reynolds numbers varied between 125 and 4992 and between 250 and 9985 for the 1 and 2 mm channels, respectively. For the 2 mm diameter channel, adding micro-inserts raised the overall pressure drop with increased Reynolds number. The inclusion of micro-inserts increased the pressure drop in the 1 mm channel at first, and thereafter the pressure drop decreased. Incorporating micro-inserts into the channel resulted in enhanced heat transfer. The trade-off between enhanced heat transfer performance and a larger pre... [more]
3119. LAPSE:2023.36401
Novel Copper Oxide Phyto-Nanocatalyst Utilized for the Synthesis of Sustainable Biodiesel from Citrullus colocynthis Seed Oil
July 13, 2023 (v1)
Subject: Energy Systems
Keywords: biocatalyst, colocynth, green fuel, non-edible feedstock, Renewable and Sustainable Energy
The green chemistry method for nanocatalyst synthesis along with environmentally feasible non-edible sources are promising alternatives to fossil fuels. The current study focuses on the synthesis of copper oxide phyto-nanocatalyst and the identification of a new renewable feedstock, Citrullus colocynthis, to reduce environmental pollution. The highest biodiesel yield (95%) was obtained under optimum conditions of a 1:8 oil-to-methanol ratio and reaction temperature of 85 °C for 120 min with a 0.365 wt% catalyst concentration. The phyto-nanocatalyst was synthesized using seed oil cake after extracting oil with the salt of copper (copper oxide). The catalyst was then subjected to various analyses, namely, EDX, FT-IR, SEM, and XRD. The catalyst was proved to be efficient and effective after being reused five times and still there was a very small difference in biodiesel yield. All the analyses also show sustainable and stable results. Thus, copper oxide phyto-nanocatalyst with non-edible... [more]
3120. LAPSE:2023.36400
Temperature−Electrokinetic Co-Driven Perfluorooctane Sulfonic Acid (PFOS) Adsorption on Geo-Adsorbents
July 13, 2023 (v1)
Subject: Process Control
Keywords: adsorption kinetics, adsorption thermodynamics, electrokinetic, electroosmotic flow, PFOS, temperature
Per- and polyfluoroalkyl substances (PFAS) have concerned the public due to their worldwide distribution and the threat they pose to drinking water safety and human health. Temperature and DC field-induced electroosmotic flow (EOF) are powerful tools to regulate organic contaminant adsorption and control PFOS (as a typical PFAS) transport in porous media. However, the co-driven mechanisms of temperature−electrokinetic transport of contaminants are still unclear. Here, we investigated the synergistic mechanisms of temperature−electrokinetic co-driven PFOS adsorption on zeolite and activated carbon as model geo-adsorbents. We found that DC fields increased PFOS adsorption on activated carbon by up to 19.8%, while they decreased PFOS adsorption on zeolite by up to 21.4%. Increasing the temperature decreased the adsorption of PFOS by activated carbon and zeolite. The temperature and electrokinetic synergistically drive EOF velocity to control PFOS adsorption. Synergistic mechanisms of temp... [more]
3121. LAPSE:2023.36399
A Feasibility Study on the Use of Injection Molding Systems for Mass Production of 100W Class Wind Turbine Blades
July 13, 2023 (v1)
Subject: Energy Systems
Keywords: injection molding, mass production, Moldflow, small wind turbine
A feasibility study on the mass production of a small wind turbine blade using an injection molding process was conducted. The blade was divided into three sections suitable for injection molding, and the mold was designed and analyzed using Moldflow CAE S/W. The optimal feedstock material was selected through comparison and analysis of three candidate materials. A mold was manufactured to test the injection molding process and evaluate related parameters. The resulting blade was assembled with other components, and a generator was installed to assess its durability, safety, and performance under various conditions. The results indicated the feasibility of producing a blade for a small wind turbine through injection molding, which predicted higher productivity and lower costs compared to traditional manufacturing methods that rely heavily on manual labor.
3122. LAPSE:2023.36398
Comparison and Analysis of Several Quantitative Identification Models of Pesticide Residues Based on Quick Detection Paperboard
July 13, 2023 (v1)
Subject: System Identification
Keywords: data averaging, image processing, pesticide residue, prediction model, RGB color model
Pesticide residues have long been a significant aspect of food safety, which has always been a major social concern. This study presents research and analysis on the identification of pesticide residue fast detection cards based on the enzyme inhibition approach. In this study, image recognition technology is used to extract the color information RGB eigenvalues from the detection results of the quick detection card, and four regression models are established to quantitatively predict the pesticide residue concentration indicated by the quick detection card using RGB eigenvalues. The four regression models are linear regression model, quadratic polynomial regression model, exponential regression model and RBF neural network model. Through study and comparison, it has been shown that the exponential regression model is superior at predicting the pesticide residue concentration indicated by the rapid detection card. The correlation value is 0.900, and the root mean square error is 0.106.... [more]
3123. LAPSE:2023.36397
Optimization Design of an Intermediate Fluid Thermoelectric Generator for Exhaust Waste Heat Recovery
July 13, 2023 (v1)
Subject: Optimization
Keywords: intermediate fluid, Optimization, power deviation, thermoelectric generator
The intermediate fluid thermoelectric generator (IFTEG) represents a novel approach to power generation, predicated upon the principles of gravity heat pipe technology. Its key advantages include high-power output and a compact module area. The generator’s performance, however, is influenced by the variable exhaust parameters typical of automobile operation, which presents a significant challenge in the design process. The present study establishes a mathematical model to optimize the design of the IFTEG. Our findings suggest that the optimal module area sees substantial growth with an increase in both the exhaust heat exchanger area and the exhaust flow rate. Interestingly, the optimal module area appears to demonstrate a low sensitivity to changes in exhaust temperature. To address the challenge of determining the optimal module area, this study introduces the concept of peak power deviation. This method posits that any deviation from the optimal module area results in an equivalent... [more]
3124. LAPSE:2023.36396
A Review of Third Generation Solar Cells
July 13, 2023 (v1)
Subject: Energy Systems
Keywords: dye-sensitized, organic photovoltaics, Perovskite, quantum dot, Shockley–Queisser limit, tandem solar cells, third generation
Third-generation solar cells are designed to achieve high power-conversion efficiency while being low-cost to produce. These solar cells have the ability to surpass the Shockley−Queisser limit. This review focuses on different types of third-generation solar cells such as dye-sensitized solar cells, Perovskite-based cells, organic photovoltaics, quantum dot solar cells, and tandem solar cells, a stacked form of different materials utilizing a maximum solar spectrum to achieve high power conversion efficiency. Apart from these solar cells, other third-generation technologies are also discussed, including up-conversion, down-conversion, hot-carrier, and multiple exciton. This review provides an overview of the previous work in the field, alongside an introduction to the technologies, including their working principles and components. Advancements made in the different components and improvements in performance parameters such as the fill factor, open circuit voltage, conversion efficienc... [more]
3125. LAPSE:2023.36395
Comparative Analysis of Paddy Harvesting Systems toward Low-Carbon Mechanization in the Future: A Case Study in Sri Lanka
July 13, 2023 (v1)
Subject: Environment
Keywords: combine harvesting, effective field capacity, greenhouse gas emissions, manual harvesting, reaper harvesting
In this study, three paddy harvesting systems, manual harvesting of paddy (MHP), reaper harvesting of paddy (RHP), and combine harvesting of paddy (CHP), were evaluated considering field capacities, field efficiencies, time and fuel consumption, mechanization indices, greenhouse gas emissions, straw availability, and direct and indirect costs. Field experiments were conducted in the North Central Province of Sri Lanka. The effective field capacity, field efficiency and fuel consumption of the combine harvester were 0.34 hah−1, 60.8%, and 34.1 Lha−1, respectively, and those of the paddy reaper were 0.185 hah−1, 58.2%, and 3.8 Lha−1, respectively. The total time consumed by MHP, RHP, and CHP were 76.05 hha−1, 39.76 hha−1, and 2.94 hha−1, respectively. The highest energy utilization was recorded by the CHP, at 1851.09 MJha−1, while MHP recorded the lowest at 643.20 MJha−1. The direct cost of the MHP was 1.50 and 1.52 times higher than those of the CHP and RHP, respectively. MHP recorded t... [more]
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