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A Comprehensive Prediction Method for Pore Pressure in Abnormally High-Pressure Blocks Based on Machine Learning
Huayang Li, Qiang Tan, Jingen Deng, Baohong Dong, Bojia Li, Jinlong Guo, Shuiliang Zhang, Weizheng Bai
November 30, 2023 (v1)
Subject: Other
Keywords: empirical models, Extra Trees, KNN, LightGBM, Machine Learning, overpressure, pore pressure prediction, Random Forest, well logs
In recent years, there has been significant research and practical application of machine learning methods for predicting reservoir pore pressure. However, these studies frequently concentrate solely on reservoir blocks exhibiting normal-pressure conditions. Currently, there exists a scarcity of research addressing the prediction of pore pressure within reservoir blocks characterized by abnormally high pressures. In light of this, the present paper introduces a machine learning-based approach to predict pore pressure within reservoir blocks exhibiting abnormally high pressures. The methodology is demonstrated using the X block as a case study. Initially, the combination of the density−sonic velocity crossplot and the Bowers method is favored for elucidating the overpressure-to-compact mechanism within the X block. The elevated pressure within the lower reservoir is primarily attributed to the pressure generated during hydrocarbon formation. The Bowers method has been chosen to forecast... [more]
Experimental Investigation of the Relationship of Failure Mode and Energy Dissipation in Grouted Rockbolt Systems under Pullout Load
Shuisheng Yu, Yawei Wang, Honghao Yang, Shucan Lu
November 30, 2023 (v1)
Keywords: energy dissipation, failure mode, grouted rockbolt systems, load transfer, pullout load
In underground engineering, the deformation of surrounding rock caused by “three heights and one disturbance” leads to the failure of grouted rockbolt systems, which causes huge economic losses to the mining industry. The research shows that the failure process of grouted rockbolt systems is the result of energy accumulation and release, but the relationship between failure mode and energy dissipation is rarely studied. Based on this, the load transfer behavior, energy dissipation, failure mode and failure mechanism of the grouted rockbolt systems are investigated from the perspective of energy in this study using the indoor pullout test. Test results show that the load decreases rapidly, and the absorbed energy decreases due to the whole-body splitting crack. The absorbed energy of the specimen in the splitting crack mode is lower than that in the pullout failure mode. When the pullout load reaches its peak, the pullout load of the specimen with split failure mode decreases sharply. M... [more]
Assessment of Triglyceride Droplet Crystallization Using Mixtures of β-Lactoglobulin and Phospholipids as Emulsifiers
Jasmin Reiner, Marian Schwenkschuster, Leon Harnisch, Volker Gaukel, Heike Petra Karbstein
November 30, 2023 (v1)
Subject: Materials
Keywords: dispersion, droplet crystallization, O/W emulsion, phospholipids, triglyceride, β-lactoglobulin
Many applications in the life science and food industries require (semi-)crystalline oil-in-water (O/W) dispersions. Unfortunately, high supercooling and, thus, low temperatures are often needed to induce the crystallization of droplets. As low molecular weight emulsifiers (LMWEs) are able to act as nucleation templates, they might help to decrease the required level of supercooling. Furthermore, proteins and LMWEs are frequently co-formulated to improve the colloidal stability of emulsions and dispersions. Hence, choosing a suitable protein and LMWE mixture would allow for achieving specific product properties for controlling the solid fat content (SFC) and take advantage of the stabilization mechanisms of both emulsifiers. Therefore, this study focuses on the impact of the co-existence of β-lactoglobulin (β-lg) and phospholipids (PLs) LMWEs on the SFC of triglyceride (TAG) droplets at isothermal conditions using a thermo-optical method. When β-lg alone was used as an emulsifier, a ma... [more]
A Study on the Oil-Bearing Stability of Salt-Resistant Foam and an Explanation of the Viscoelastic Phenomenon
Changhua Yang, Zhenye Yu
November 30, 2023 (v1)
Subject: Materials
Keywords: droplet aggregation, foam rheology, foam stability, polymer foam
Foam is a medium-stable system composed of gas and liquid phases, which has the advantages of low density at the gas phase and high viscosity at the liquid phase, and has a wide application in oil and gas field development and mineral flotation, but its special medium-stable system also brings many problems in industry applications. Scientists have carried out extensive analyses and research on the foam stability and bubble-bursting mechanism, which initially clarified the rules of bubble breakage caused by environmental factors such as temperature and pressure, but the mechanism of bubble bursting under the action of internal factors such as liquid mineralization and oil concentration of the films is still not clearly defined. In this paper, we propose a compound salt-resistant foaming agent, investigated the influence of the aggregation and adsorption behavior of oil droplets on the liquid films and boundaries, and established a relevant aggregation and adsorption model with the popu... [more]
Evaluating Fractal Damage and Acoustic Emissions of Soft Rock−Coal Combinations in a Deep Mining Area
Bin Liang, Dong Wang, Yujing Jiang, Xiaoming Sun, Hengjie Luan, Changsheng Wang, Ling Dong, Lugen Chen
November 30, 2023 (v1)
Keywords: acoustic emission, deep mining area, fractal damage, soft rock–coal combinations
Weakly cemented soft rock mines in the Ordos Basin are susceptible to mining disasters, including roof collapse and substantial deformation of surrounding rocks, during coal mining operations. Researching the damage characteristics of structures composed of low-strength “soft rock−coal” combinations is crucial for effectively preventing and controlling disasters in deep soft rock mining. To investigate the fractal damage characteristics of soft rock−coal combinations with different height ratios, uniaxial compression tests were conducted on specimens containing soft rock percentages of 20%, 40%, 50%, 60%, and 80%. The results show that the uniaxial compressive strength and modulus of elasticity of the soft rock−coal combinations increased with increasing proportions of soft rock. The soft rock−coal combination was clearly segmented, and the 40%, 50%, and 60% soft rock−coal combinations had good self-similarity. The fractal dimensions were 2.374, 2.508 and 2.586, which are all within th... [more]
A New Integrated Model for Simulating Adaptive Cycle Engine Performance Considering Variations in Tip Clearance
Jie Wei, Wangzhi Zou, Zhaoyun Song, Baotong Wang, Jiaan Li, Xinqian Zheng
November 30, 2023 (v1)
Keywords: adaptive cycle engine, engine performance simulation, integrated model, multi-fidelity simulation model, tip clearance
The low-fidelity simulation method cannot meet the requirements for predicting the performance of an adaptive cycle engine (ACE), especially when considering tip clearance variations in the compression and expansion systems. The tip clearances of the components of an ACE, such as the adaptive fan and turbine, vary drastically under different operating conditions. Though the tip clearance significantly impacts the engine’s performance, including its thrust and fuel consumption, variations in tip clearance are not considered in traditional ACE simulation models. This paper developed a new integrated model for predicting ACE performance, including multi-fidelity simulation models of the components and a newly developed, simplified model for predicting tip clearance. Specifically, the integrated model consists of a zero-dimensional (0D) engine performance simulation model, a three-dimensional (3D) adaptive fan numerical simulation model, a one-dimensional (1D) low-pressure-turbine (LPT) me... [more]
Numerical Evaluation of the Effect of Buoyancy-Driven Flow on the Migration of Respiratory Droplets
Nan Li, Xiaohong Yan
November 30, 2023 (v1)
Keywords: buoyancy, dispersion, indoor, respiratory droplet, Simulation
The understanding of the impact of buoyancy-driven flow on the migration of respiratory droplets remains limited. To investigate this phenomenon, the Lagrangian−Eulerian approach (k-ε turbulent model and discrete phase model) was employed to analyze the interaction between buoyancy-driven flow and coughing activity. The simulation approach was validated by simulating a jet problem in water. Although this problem describes the jet penetration in water, the governing equations for this problem are the same as those for coughing activity in the air. The results demonstrated that an umbrella-shaped airflow was generated above a person and a temperature stratification existed in the room. The buoyancy-driven flow significantly altered the dispersion pattern of the droplets. Notably, for large droplets with an initial diameter of 100 μm, the flow in the boundary layer led to an increased deposition time by about five times. Conversely, for small droplets with an initial diameter of 20 μm, th... [more]
Effect of Cavitating Hydraulic Elements on Pump Characteristics
Jana Jablonská, Milada Kozubková, Sylva Drábková, Tomáš Blejchař
November 30, 2023 (v1)
Keywords: cavitation, converging-diverging nozzle, NPSH, pump, suction piping
The effective and reliable performance of any pump can be significantly impacted by the piping system design. One of the essential points is the pump suction pipe. Poor design and dimension of the suction piping can lead to cavitation in the pump which affects its head and efficiency. The primary objective is to reduce the hydraulic losses of the suction piping in order to maintain a Net Positive Suction Head required by the pump. Suction piping is recommended to be short and straight, and branch connections, valves and elbows should be avoided, which is not always possible. In addition, cavitation can occur in the actual hydraulic elements installed on the pump suction. This work is focused on the investigation of cavitating hydraulic element in the suction pipe on the pump performance. A converging-diverging nozzle with a circular cross-section was used for this purpose. A straight pipe segment of constant diameter and the same length was used for comparison. Both elements were chara... [more]
Special Issue on “Machine-Learning-Assisted Intelligent Processing and Optimization of Complex Systems”
Xiong Luo, Manman Yuan
November 30, 2023 (v1)
Subject: Optimization
Complex systems and their various characteristics have been widely considered in economic and industrial systems [...]
Prediction Model of Fouling Thickness of Heat Exchanger Based on TA-LSTM Structure
Jun Wang, Lun Sun, Heng Li, Ruoxi Ding, Ning Chen
November 30, 2023 (v1)
Keywords: attention mechanism, deep learning, heat exchanger fouling, neural network, two-layer LSTM
Heat exchangers in operation often experience scaling, which can lead to a decrease in heat exchange efficiency and even safety accidents when fouling accumulates to a certain thickness. To address this issue, manual intervention is currently employed to monitor fouling thickness in advance. In this study, we propose a two-layer LSTM neural network model with an attention mechanism to effectively learn fouling thickness data under different working conditions. The model accurately predicts the scaling thickness of the heat exchanger during operation, enabling timely human intervention and ensuring that the scaling remains within a safe range. The experimental results demonstrate that our proposed neural network model (TA-LSTM) outperforms both the traditional BP neural network model and the LSTM neural network model in terms of accuracy and stability. Our findings provide valuable technical support for future research on heat exchanger descaling and fouling growth detection.
Unveiling the Latest Breakthroughs in Menaquinone-7 Research through Fermentation-Based Production
Aydin Berenjian, Nima Yazdanpanah
November 30, 2023 (v1)
Subject: Biosystems
Keywords: biofilm reactors, fermentation-based production, health benefits, menaquinone-7 (MK-7), optimization of MK-7 biosynthesis
MK-7, like other biological molecules, exists in geometric isomers, including cis and trans forms, among which only the all-trans form holds biological significance. Recent studies have drawn attention to the manifold health advantages linked to the consumption of menaquinone-7 (MK-7). Nonetheless, the scarcity of MK-7 in natural dietary sources underscores the necessity for creating dietary supplements to fulfil daily intake requisites. Obtaining MK-7 involves employing production techniques encompassing solid- or liquid-state fermentation. However, upscaling this process becomes intricate in static fermentation due to challenges in heat and mass transfer. Consequently, the bulk of research on MK-7 synthesis via fermentation has concentrated on the liquid-state approach. To this end, endeavors have been dedicated to refining MK-7 biosynthesis by exploring diverse fermentation media compositions, optimal growth conditions, and even integrating nanobiotechnology methodologies. Innovativ... [more]
Colloidal TiO2 Nanorod Films Deposited Using the MAPLE Technique: Role of the Organic Capping and Absence of Characteristic Surface Patterns
Maura Cesaria, Antonietta Taurino, Pantaleo Davide Cozzoli, Valentina Arima, Anna Paola Caricato
November 30, 2023 (v1)
Subject: Materials
Keywords: elemental/morphological analyses, laser fluence, MAPLE technique, missing MAPLE surface patterns, organic capping, photocatalytic degradation, thin films, TiO2 nanorods
Thin films of titanium dioxide (TiO2) nanocrystals, widely acknowledged for their unique physical-chemical properties and functionalities, are used in disparate technological fields, including photovoltaics, sensing, environmental remediation and energy storage. In this paper, the preparation of thin films consisting of anatase-phase TiO2 nanorods deposited using the matrix-assisted pulsed laser evaporation (MAPLE) technique and their characterization in terms of morphology, elemental composition and wettability are presented and discussed. Particular attention is paid to the effects of the laser fluence, varied over a broad range (F = 25, 50, 100 mJ/cm2), and to the role of the capping surfactants bound to the surface of the nanorod precursors. Whereas increasing fluence favored a partial removal of the surface-bound surfactants, a post-growth UV-light-driven photocatalytic treatment of the films was found to be necessary to reduce the incorporated fraction of organics to a further su... [more]
Evaluation of Potential Factors Affecting Steel Slag Carbonation
Amer Baras, Jiajie Li, Wen Ni, Zahid Hussain, Michael Hitch
November 30, 2023 (v1)
Subject: Materials
Keywords: accelerated carbonation, carbonation curing, steel slag, steel slag carbonations’ influencing factors
Steel slag is a solid waste product generated during the carbonation stage of steelmaking. It has high levels of heavy metals and substantial amounts of free calcium and magnesium oxide, making it unsuitable for use as a cement material. Furthermore, the disposal of steel slag in landfills requires many resources and can seriously contaminate the surrounding environment. One method of reducing its negative environmental impact is carbonation, which involves reacting steel slag with carbon dioxide to form stable minerals. However, many parameters influence the carbonation efficiency of steelmaking slag, including temperature, time, particle size, pressure, CO2 concentration, liquid-to-solid ratio, moisture content, humidity, additives, etc. To this end, this paper comprehensively reviews the most important steel slag carbonation-influencing factors. Moreover, it compares the characteristics from two perspectives based on their causes and effects on carbonation. Finally, this article rev... [more]
Design and Study of a Large-Scale Microwave Plasma Torch with Four Ports
Yedai Hu, Wencong Zhang, Jiahui Han, Huacheng Zhu, Yang Yang
November 30, 2023 (v1)
Keywords: 3D model, four-port microwave source, high microwave efficiency, large-scale MPT
The microwave plasma torch (MPT) has gained popularity in industrial applications due to its high energy density, ionization levels, and high temperature. However, the non-uniform and unstable plasma generated by microwave plasma sources has limited the production of large-scale MPTs. This paper proposes a novel MPT device utilizing a four-port microwave source (2.45 GHz, 4 kW) to address these issues. The improved plasma uniformity and stability are achieved through the new structure, and the microwave efficiency is enhanced by introducing the focusing dielectric in the coupled cavity. Using a 3D electromagnetic field model, microwave plasma model and fluid model, the paper optimizes the geometry and inlet mode of the MPT device. Experimental results show that the novel MPT device can generate a plasma torch with a maximum height of 545 mm, a working range of 10−95 L/min, and a microwave efficiency up to 86%. The proposed device not only competently meets industrial requirements, but... [more]
Photocatalytic Degradation of Neonicotinoid Insecticides over Perlite-Supported TiO2
Vanja Kosar, Ana-Marija Križanac, Ivana Elizabeta Zelić, Stanislav Kurajica, Vesna Tomašić
November 30, 2023 (v1)
Keywords: acetamiprid, design of experiments (DoE), immobilization, perlite-based TiO2, photocatalytic degradation, response surface methodology (RSM)
The aim of this study was to investigate the photocatalytic degradation of the neonicotinoid insecticide acetamiprid in aqueous solution. Experiments were carried out in a 250 mL batch reactor with recirculation of the reaction mixture and using a UVA-LED radiation source with a heterogeneous UVC-modified perlite-based TiO2 photocatalyst. The photocatalytic degradation of acetamiprid was optimized using a Box−Behnken design (BBD) of the response surface methodology (RSM). The variables in the process optimization were catalyst type, volume of the reaction mixture, and light radiation intensity. From the experimental data obtained, the conversions of the photocatalytic reactions, the reaction rate constants, and the mean square deviations were calculated. The experimental results have shown that the conversion of the reaction is significantly affected by the type of catalyst, i.e., the method used to immobilise the photocatalytic layer on the perlite granules. The highest conversions of... [more]
Pump-Controlled AGC Micro-Displacement Position Control of Lithium Battery Pole Strip Mill Based on Friction Model
Kai Wang, Gexin Chen, Tiangui Zhang
November 30, 2023 (v1)
Keywords: electro-hydraulic servo pump control, friction compensation, LuGre model, position control
Electrode roll-forming refers to rolling a battery electrode into a preset thickness through the electro-hydraulic servo pump-controlled hydraulic roll gap thickness automatic control system (known to as pump-controlled AGC). Compared with the motor servo system, the friction problem of the electro-hydraulic servo system is more serious and the friction problem of the actuator itself is very prominent. Moreover, low-speed performance is one of its core indicators, the friction phenomenon is the most abundant during the low-speed stage and the impact on the servo system is also the most obvious. Therefore, for high-performance electro-hydraulic servo control, friction compensation is not only unavoidable, but also a very difficult problem. Aiming to influence the friction on the position control of the pump-controlled system of a lithium battery pole strip mill, the rolling mechanism and process procedure under micro-displacement position control based on the friction model were studied... [more]
Research on Classified Treatment of Electrolytic Zn Anode Slime Based on μ-XRF and Cluster Heatmap
Ruichao Xu, Linhua Jiang, Ning Duan, Guangbin Zhu, Yong Liu, Chao Zhou, Weidong Li, Zhiqiang Li
November 30, 2023 (v1)
Keywords: anode slime, cleaner production, cluster heatmap, Pb-based anode, μ-XRF
The purpose of this research is to have a clearer understanding of the resource value of electrolytic Zn anode slime, explore its fine structure and treat it in a classified manner. In this paper, the composition, content and distribution of Pb, Mn and Zn in electrolytic Zn anode slime during one production cycle were studied under typical working conditions of enterprises, by using the method of μ-XRF combined with mm-XRF. Based on heatmap and cluster analysis, the resource value of anode slime at different points in the electrolytic Zn silting area and the conventional area was evaluated. The research results were as follows: (1) There were two different areas of electrolytic Zn anode slime: the silting area and conventional area. Between these, the silting area accounted for approximately 15% of the total number of anode plates, and there were significant differences between these areas in terms of surface element content, surface morphology, slime thickness and water content. (2) I... [more]
Determination of Ten Plant Growth Regulators in Bean Sprouts by Mixed Solid Phase Extraction Columns Separation and LC-MS/MS
Chenggang Cai, Feng Yao, Chuanpeng Li, Yannan Xiang, Pinggu Wu, Zhengyan Hu, Junlin Wang, Ruiyu Zhu
November 30, 2023 (v1)
Subject: Materials
Keywords: bean sprout, food safety, liquid chromatography/mass spectrometry/mass spectrometry, plant growth regulator
(1) Background: Plant growth regulators (PGRs) can accelerate growth or improve the quality and quantity of bean sprouts but are forbidden to use in bean sprout cultivation, as the sprouting process’s increased chemicals will disturb the PGRs analysis. This article aimed to increase the accuracy and level of sensitivity of the LC-MS/MS method for the simultaneous analysis of 10 PGRs after mixed solid phase extraction (SPE) purification. (2) Methods: An LC-MS/MS detection method for 10 kinds of PGRs was established based on ESI ionization in the positive ion mode for 6-furfurylaminopurine (6-KT), paclobutrazol (PBZ), indole-2-acetic acid (IAA), and indole-3-butyric acid (IBA) and in the negative ion mode for gibberellin A3 (GA3), 2,4-dichlorophenoxy acetic acid (2,4-D), 4-chlorophenoxyacetic acid (4-CPA), forchlorfenuron (FCF), thidiazuron (TDZ), and 6-benzyl adenine (6-BA). (3) Results: The 10 PGR compounds were detected within a concentration range of 1.0−50 ng/mL. The average recover... [more]
A Hybrid Cluster Variational Autoencoder Model for Monitoring the Multimode Blast Furnace System
Chenyu Chen, Jinhui Cai
November 30, 2023 (v1)
Keywords: Gaussian mixture model, multimode blast furnace system, process monitoring, variational autoencoder
Efficient monitoring of the blast furnace system is crucial for maintaining high production efficiency and ensuring product quality. This article introduces a hybrid cluster variational autoencoder model for monitoring the blast furnace ironmaking process which exhibits multimode behaviors. In contrast to traditional approaches, this method utilizes neural networks to learn data features and effectively handles the diverse feature types observed in different production modes. Through the utilization of a clustering process within the hidden layer of the variational autoencoder, the proposed technique facilitates efficient fault detection in the context of multimodal blast furnace data. Based on the variational autoencoder model, this study further establishes a unified monitoring index and defines a method for computing the control limits. The application of the model to real blast furnace data reveals its proficiency in accurately identifying faults across diverse modes; compared with... [more]
Modeling and Cleaning Performance Optimization of Conical Filter Cartridge of Gas Turbine Intake Filter
Jiangang Yi, Jiayi Duan, Rui Yuan, Wen Bo, Xiaolong Ruan
November 30, 2023 (v1)
Keywords: conical filter cartridge, evaluation of ash removal effect, numerical simulation, pulse cleaning
Intake quality is crucial to gas turbines’ operation. The cartridge filter in the gas turbine intake system filters the gas and outputs a highly clean gas into the gas turbine, while pulse cleaning technology ensures the continuous and efficient operation of cartridge filters. While the current cylindrical pleated filter cartridge used in pulse cleaning usually suffers from insufficient upper cleaning, the conical pleated filter cartridge can effectively solve this issue by providing a greater upper cleaning area with significant application prospects. Despite the existing potential, research on conical filter cartridge cleaning performance is limited; thus, this paper aims to investigate the advantages of pulse cleaning using a conical filter cartridge via numerical simulation. Results demonstrate that while the conical filter cartridge enhances the cleaning strength, cleaning uniformity decreases slightly. To address this shortcoming, this paper innovatively proposes a combination of... [more]
Vacuum-Packed Pork Sausages with Modified Casing Added with Orange Peel Extracts: Evaluating In Vitro Antioxidant Activity via Hyperspectral Imaging Coupled with Chemometrics
Chao-Hui Feng
November 30, 2023 (v1)
Keywords: DPPH, flavonoids, multivariate analysis, natural casing, orange wastes
The antioxidant activities (in vitro) of vacuum-packaged dry-cured sausages stored for 1 year, which were treated with varying concentrations of extracts from orange peel (EFOP) in a modification solution, were evaluated using a central composite design. The individual variables: soy lecithin concentration, soy oil concentration, treated time, lactic acid addition, EFOP addition, and dependent variable [i.e., in vitro antioxidant activity] were analyzed by response surface methodology. Among the 32 treatment combinations, treatment 26 (central point) exhibited a higher 2,2-Diphenyl-1-picrylhydrazyl (DPPH) radical scavenging activity compared to the control group (natural hog casing without modification). Spectral pre-treatments were applied to enhance the robustness of the model, and a partial least squares regression model (PLSRM) was fitted. The results of the response surface methodology indicated that the interactive effects of a high [soy lecithin concentration] × a high [EFOP add... [more]
Development of a Design Method for Casing and Tubing Strings under Complex Alternating Loads
Jianjun Wang, Dening Li, Xu Du, Hongjie Li, Shangyu Yang
November 30, 2023 (v1)
Keywords: casing, oil and gas well, pipe string design, tubing
With the escalating intricacy of downhole operational scenarios, encompassing frequent well cycling, acidification, multi-stage fracturing, steam injection, and intensive extraction, the efficacy of traditional casing-string-design methods rooted in strength considerations is progressively unveiling its limitations. Henceforth, it becomes imperative to establish string-design method standards that embrace the entirety of a well’s lifecycle, encompassing the phases of drilling, completion, fracturing, and production operations. Beginning with an analysis of the advantages and limitations of traditional casing-string-design methods, this paper introduces the features of strain and sealing design methods developed for the full lifecycle of the string. The strain design method, a departure from conventional design philosophies, enables the design concept of the controllable deformation of the pipe string. The sealing design method currently stands as the sole standard method for the design... [more]
Extraction and Purification of Kiwifruit Seed Oil Using Three-Phase Partitioning: An Efficient and Value-Adding Method for Agro-Industrial Residue Utilization
Bangfu Liu, Xiufang Li, Qingchun Liu, Zhijian Tan
November 30, 2023 (v1)
Keywords: extraction and separation, kiwifruit seed oil, three-phase partitioning, waste utilization
Kiwifruit seeds are usually discarded as waste in the kiwifruit processing industry. However, kiwifruit seeds are rich in oil, which implies their value as a potential resource. Therefore, three-phase partitioning (TPP) using ammonium sulfate and n-butanol has been developed to extract kiwifruit seed oil (KSO) from discarded kiwifruit seeds. The factors influencing the extraction process have been investigated. The highest extraction yield of 36.06% for KSO was obtained under the following conditions: an extraction time of 18 h, a liquid-solid ratio of 4:1, an amount of ammonium sulfate of 28.5 wt%, and a phase ratio (top phase/bottom phase) of 1/1. The composition of obtained KSO was analyzed by gas chromatography-mass spectrometry (GC-MS), and the results indicated the high content of α-linolenic acid. This simple and low-cost method can be used as an efficient approach for utilizing the value of kiwifruit seeds.
Improving the Process of Product Design in a Phase of Life Cycle Assessment (LCA)
Andrzej Pacana, Dominika Siwiec, Lucia Bednárová, Ján Petrovský
November 30, 2023 (v1)
Subject: Environment
Keywords: design, impact on environment, LCA, life cycle assessment, photovoltaic panel, product, production engineering, quality, relative state scale, weighted sum model
The early phases of product development effect fundamental changes in products throughout their life cycle. Therefore, the objective of the investigation was to develop a simplified model that supports the process of product design simultaneously in terms of qualitative and environmental factors. The model is dedicated to the design phase in the life cycle assessment of the product (LCA). The originality of the model consists in: (i) analysis of customers’ satisfaction from qualitative alternatives of products; (ii) assessments of the environmental impact of these alternatives; (iii) definition of the importance of qualitative and environmental attributes of products; and (iv) prediction of favourable changes in products according to qualitative−environmental levels. The model was tested for photovoltaic panels (PVs). The model is mainly dedicated to small and medium-sized enterprises (SMEs) for support in making decisions in the design phases of products in their life cycles.
Recent Progress in Fill Media Technology for Wet Cooling Towers
Zahra Hashemi, Abdolmajid Zamanifard, Maysam Gholampour, Jane-Sunn Liaw, Chi-Chuan Wang
November 30, 2023 (v1)
Subject: Materials
Keywords: cooling tower, fill configuration, fill material, fill media
Cooling towers are extensively utilized in diverse industries for efficient heat dissipation. Fill media are a critical component, facilitating heat and mass exchange between water and air, impacting overall cooling tower efficiency. Given its vital importance, this study comprehensively reviews recent advancements in fill media technology, illuminating cooling tower technology progress and exploring the effects of different fill media configurations and materials on cooling tower performance. It should be noted that the majority of research is focused on the Range of 2.5 °C to 25 °C and Approach of 1 °C to 9 °C. Through comprehensive analysis and evaluation, the effects of various fill media on heat transfer efficiency, water cooling capacity, and energy consumption are intensively summarized. By understanding these effects, engineers and designers can make rational decisions to optimize cooling tower performance and ensure efficient heat dissipation. Notably, in some reported cases,... [more]
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