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Showing records 37200 to 37224 of 43292. [First] Page: 1 1485 1486 1487 1488 1489 1490 1491 1492 1493 Last
37200. LAPSE:2023.1930
Numerical Study of Factors Affecting Particle Suction Efficiency of Pick-Up Head of a Regenerative Air Vacuum Sweeper
February 21, 2023 (v1)
Subject: Modelling and Simulations
Keywords: computational fluid dynamics (CFD), discrete particle model (DPM), particle removal starting speed, pick-up head, regenerative air vacuum sweeper, suction efficiency
The influence of variable operational conditions affects the performance of particle collection and separation of a regenerative air vacuum sweeper. Therefore, the purpose of this paper was to numerically investigate the factors affecting the particle suction efficiency of the pick-up head. Using computational fluid dynamics (CFD), a model of an integrated pick-up head was developed based on the particle suction process to evaluate the particle removal performance. The realizable k-ε and discrete particle models were utilized to study the gas flow field and solid particle trajectories. The particle structure, sweeping speed, secondary airflow, pressure drop, and distance between the particle suction port and the road surface, as factors that affect the particle removal efficiency, were investigated. The results indicate that the particle suction efficiency increases with decreasing sweeper speed. Furthermore, the particle overall removal efficiency increased with a reduction in the dis... [more]
37201. LAPSE:2023.1929
A Gold Nanoparticle-Based Molecular Self-Assembled Colorimetric Chemosensor Array for Monitoring Multiple Organic Oxyanions
February 21, 2023 (v1)
Subject: Materials
Keywords: chemosensor array, gold nanoparticles, linear discrimination analysis (LDA), multicomponent analysis, organic oxyanions, support vector machine (SVM)
Determination of oxyanions is of paramount importance because of the essential role they play in metabolic processes involved in various aquatic environmental problems. In this investigation, a novel chemical sensor array has been developed by using gold nanoparticles modified with different chain lengths of aminothiols (AET-AuNPs) as sensing elements. The proposed sensor array provides a fingerprint-like response pattern originating from cross-reactive binding events and capable of targeting various anions, including the herbicide glyphosate. In addition, chemometric techniques, linear discrimination analysis (LDA) and the support vector machine (SVM) algorithm were employed for analyte classification and regression/prediction. The obtained sensor array demonstrates a remarkable ability to determine multiple oxyanions in both qualitative and quantitative analysis. The described methodology could be used as a simple, sensitive and fast routine analysis for oxyanions in both laboratory... [more]
37202. LAPSE:2023.1928
Airflow Distributions in a Z Type Centripetal Radial Flow Reactor: Effects of Opening Strategy and Opening Rate
February 21, 2023 (v1)
Subject: Modelling and Simulations
Keywords: opening rate, opening strategy, radial flow reactor, Z-type centripetal
Computational fluid dynamics (CFD) was adopted to investigate the influence of the three-section opening strategy in the Z type centripetal radial flow reactor on the uniformity of the gas flow, which aimed to optimize the opening rate of the reactor. The simulation results showed that as the pore-opening ratio of are 10%, 16% and 29% for three sections from top to bottom of the central channel, the opening rate of the circular channel perforated plate is 10−12%, 21−25% and 30−40% from top to bottom, respectively; the uniformity of the reactor was then achieved. Through the simulation results, it was also found that the change in the opening rate at the center pipe perforated plate had a greater contribution to the gas flow mal-distribution inside the reactor. The contribution of the change in the opening rate of the annular channel perforated plate to the uniformity of the gas flow inside the reactor was smaller than that of the center pipe. Annular channel width should not be smaller... [more]
37203. LAPSE:2023.1927
Water Extract Ameliorates Asthma Severity by Inducing Th2 Cells’ and Pulmonary Epithelial Cells’ Apoptosis via NF-κB/COX-2 Pathway
February 21, 2023 (v1)
Subject: Biosystems
Keywords: apoptosis, asthma severity, Codonopsis laceolata, NF-κB/COX-2 pathway
Asthma is an incurable pulmonary disease with several symptoms, including abnormal breathing, coughing, and sleep apnea, which can lead to death, and the population of asthma patients has been increasing worldwide. There are many adverse effects in current drugs, and thus, we have tried to develop anti-asthmatic agents from natural products such as Codonopsis laceolata. To define the anti-asthmatic effect and the mechanism of Codonopsis laceolata, an animal study was conducted considering different cell counts of BALF, serum IgE levels, morphological changes in the pulmonary system, the Th2 cell transcription factor (GATA-3), and the apoptotic pathway (NF-κB/COX-2). Codonopsis laceolata significantly suppressed the representative asthmatic changes, such as airway remodeling, mucous hypersecretion, epithelial hyperplasia, and inflammatory cell infiltration, in the respiratory system. It suppressed the levels of GATA-3, IL-4, and IL-13. The down-regulation of Th2-related factors, such as... [more]
37204. LAPSE:2023.1926
Vaccine Commercialization: Physiochemical Factors for Optimum Production
February 21, 2023 (v1)
Subject: Energy Systems
Keywords: cultivation process, Mannheimia haemolytica, maximizing yields, minimizing cost, Pasteurella multocida, pasteurellosis, physiochemical factors
spp. are Gram-negative facultative bacteria that cause severe economic and animal losses. Pasteurella-based vaccines are the most promising solution for controlling Pasteurella spp. outbreaks. Remarkably, insufficient biomass cultivation (low cell viability and productivity) and lack of knowledge about the cultivation process have impacted the bulk production of animal vaccines. Bioprocess optimization in the shake flask and bioreactor is required to improve process efficiency while lowering production costs. However, its state of the art is limited in providing insights on its biomass upscaling, preventing a cost-effective vaccine with mass-produced bacteria from being developed. In general, in the optimum cultivation of Pasteurella spp., production factors such as pH (6.0−8.2), agitation speed (90−500 rpm), and temperature (35−40 °C) are used to improve production yield. Hence, this review discusses the production strategy of Pasteurella and Mannheimia species that can potentially be... [more]
37205. LAPSE:2023.1925
Efficient Discrete Element Modeling of Particle Dampers
February 21, 2023 (v1)
Subject: Modelling and Simulations
Keywords: contact stiffness, discrete element method, energy dissipation, GPU computing, particle damping
Particle dampers’ dissipative characteristics can be difficult to predict because of their highly non-linear behavior. The application of such devices in deformable vibrating systems can require extensive experimental and numerical analyses; therefore, improving the efficiency when simulating particle dampers would help in this regard. Two techniques often proposed to speed up the simulation, namely the adoption of a simplified frictional moment and the reduction of the contact stiffness, are considered; their effect on the simulation run-time, on the ability of the particle bed to sustain shear deformation, and on the prediction of the dissipation performance is investigated for different numerical case studies. The reduction in contact stiffness is studied in relation to the maximum overlap between particles, as well as the contacts’ duration. These numerical simulations are carried out over a wide range of motion regimes, frequencies, and amplitude levels. Experimental results are c... [more]
37206. LAPSE:2023.1924
Study on Characteristics and Control Strategy of Diesel Particulate Filters Based on Engine Bench
February 21, 2023 (v1)
Subject: Energy Systems
Keywords: active regeneration, control strategy, diesel engine, DPF, thermocouple temperature sensor
The ignition temperature of a diesel oxidation catalyst (DOC) and the internal temperature-field distribution of the diesel particulate filter (DPF) during active regeneration are investigated during an engine bench test in this study. Based on the dropped to idle (DTI) test, a test method is developed to determine the safe regeneration temperature of the DPF. The results show that when the inlet temperature of the DOC is more than 240 °C, the DOC begins ignition and reaches the target temperature of 600 °C set for active regeneration of DPF; when the inlet exhaust temperature of the DOC is between 240 and 280 °C, a higher injection rate is required to reduce the secondary pollution of HC and thus make the DPF reach the set target temperature as soon as possible. The active regeneration process of the DPF is divided into three stages. During ignition, the temperature of the DPF inlet and outlet increases rapidly and successively. The internal and outlet temperatures of DPF during regen... [more]
37207. LAPSE:2023.1923
Oxidative and Microbial Stability of a Traditional Appetizer: Aubergine Salad
February 21, 2023 (v1)
Subject: Biosystems
Keywords: aubergine salad, bioluminescence, eggplant salad, microbial stability, oil oxidation, tocopherol content
An eggplant-based salad, called aubergine salad (AS), is a traditional appetizer and as such, is quite popular in the Mediterranean area. It is widely produced either on a home scale or on an industrial scale and widely consumed. However, there are cases where preservatives (such as sodium benzoate and potassium sorbate) are added in order to extend the shelf life of the product. In the present study, the stability of this delicatessen against oxidation and microbial spoilage was evaluated, with or without preservatives. The physicochemical properties of the salad were evaluated, along with the tocopherol content, resistance to oxidation, and microbial count. According to the results, it is evident that the induction period of AS is 16% (in the case that preservatives were used) and 26% (in the case without preservatives) increased, compared to a control sample (plain soybean oil). This can be attributed to the increased content in tocopherols, and more specifically to α-tocopherol. Fu... [more]
37208. LAPSE:2023.1922
Tracking Control of a Hyperchaotic Complex System and Its Fractional-Order Generalization
February 21, 2023 (v1)
Subject: Process Control
Keywords: fractional order, hyperchaotic complex system, tracking control
Hyperchaotic complex behaviors often occur in nature. Some chaotic behaviors are harmful, while others are beneficial. As for harmful behaviors, we hope to transform them into expected behaviors. For beneficial behaviors, we want to enhance their chaotic characteristics. Aiming at the harmful hyperchaotic complex system, a tracking controller was designed to produce the hyperchaotic complex system track common expectation system. We selected sine function, constant, and complex Lorenz chaotic system as target systems and verified the effectiveness by mathematical proof and simulation experiments. Aiming at the beneficial hyperchaotic complex phenomenon, this paper extended the hyperchaotic complex system to the fractional order because the fractional order has more complex dynamic characteristics. The influences order change and parameter change on the evolution process of the system were analyzed and observed by MATLAB simulation.
37209. LAPSE:2023.1921
Performance Improvement of H8 Transformerless Grid-Tied Inverter Using Model Predictive Control Considering a Weak Grid
February 21, 2023 (v1)
Subject: Process Control
Keywords: common-mode voltage, H8, leakage current, Model Predictive Control, photovoltaic, transformerless inverter, weak grid
There is increasing utilization of photovoltaic (PV) grid-connected systems in modern power networks. Currently, PV grid-connected systems utilize transformerless inverters that have the advantages of being low cost, low weight, a small size, and highly efficient. Unfortunately, these inverters have an earth leakage current problem due to the absence of galvanic isolation. This phenomenon represents safety and electrical problems for those systems. Recently, the H8 transformerless inverter was introduced to eliminate the earth leakage current. The present study proposes improving the performance of an H8 transformerless inverter using model predictive control (MPC). The inverter was supplied by PV energy and attached to the grid through an LCL filter. During system modeling, the grid weakness was identified. The discrete model of the overall system, including the PV panel, the boost converter, the H8 transformerless inverter, and the controllers, was derived. Then, the introduced H8 tr... [more]
37210. LAPSE:2023.1920
Intensification Insights from Chemical Looping Combustion Using Coal−Biomass Mixtures with Fe-Based Oxygen Carrier
February 21, 2023 (v1)
Subject: Modelling and Simulations
Keywords: Aspen Plus, carbon capture efficiency, CLC, coal/biomass
Chemical looping combustion (CLC) is a modern technology that enables the mitigation of the CO2 concentration without any expense of energy. Experimental evidence shows that combustion of coal/biomass in CLC technology leads to negative carbon emission by replacing the portion of coal with biomass. In the present work, CLC was simulated using a mixture of coal/biomass in CLC; using their different proportions resulted in enhanced CO and CO2 fractions in the fuel reactor. The carbon capture and oxide oxygen fraction were also found to increase with the enhancement of the fuel reactor’s temperature with different proportions of coal/biomass. Increases in the carbon capture efficiency and oxide oxygen fraction of up to 98.86% and ~98%, respectively, were observed within the experimental temperature range. The simulated results of various parameters were predicted and validated with the published experimental results. The stated parameters were also predicted as a function of the different... [more]
37211. LAPSE:2023.1919
Skin-Beautifying Effects of Magnolol and Honokiol Glycosides
February 21, 2023 (v1)
Subject: Materials
Keywords: AGEs (advanced glycation end-products), antiaging, glycation induction model test, honokiol glycoside, magnolol glycoside, skin-beautifying effects
Glycosides have been synthesized using the starting materials magnolol (1) and honokiol (4), isolated from the Japanese white-bark magnolia, and their anti-aging effects on the skin (skin-beautifying effects) have been examined. The advanced glycation end-product (AGE) inhibitory activity test (anti-glycation test) and glycation induction model test, using human-derived dermal fibroblasts, TIG-110 cells, have been conducted to evaluate the anti-aging effects. The synthesized glycoside compounds, 5,5′-di(prop-2-en-1-yl)[1,1′-biphenyl]-2-hydroxy-2′-glucopyranoside (3a), 5,5′-di(prop-2-en-1-yl)[1,1′-biphenyl]-2,2′-diglucopyranoside (3b), 3′,5-di(prop-2-en-1-yl)[1,1′-biphenyl]-4′-hydroxy-2-glucopyranoside (6a) and 3′,5-di(prop-2-en-1-yl)[1,1′-biphenyl]-2,4′-diglucopyranoside (6b), have shown significant anti-glycation activities of less than 0.10 mM in IC50. The glycation induction model test with the fibroblasts, TIG-110 cells, demonstrates that the aforementioned glycosides significantly... [more]
37212. LAPSE:2023.1918
Parallel Reaction Monitoring Mode for Atenolol Quantification in Dried Plasma Spots by Liquid Chromatography Coupled with High-Resolution Mass Spectrometry
February 21, 2023 (v1)
Subject: Materials
Keywords: atenolol, DBS, DPS, dried plasma spot, LC–HRMS, parallel reaction monitoring, PRM
In this study, we reported a rapid, sensitive, robust, and validated method for atenolol quantification in dried plasma spots (DPS) by liquid chromatography with high-resolution mass spectrometry (LC-HRMS) using parallel reaction monitoring mode (PRM). Aliquots of 25 µL human plasma were placed onto Whatman 903 Cards and air-dried. Disks (3.2 mm internal diameter) were punched, and a 100 µL working internal standard solution was added to each sample and then incubated on a shaker for 15 min at 40 °C, followed by rapid centrifugation (10,000× g, 10 s). The supernatant was transferred into 300 µL vials for subsequent LC−HRMS analysis. After chromatographic separation, atenolol and the internal standard were quantified in positive-ion parallel reaction monitoring mode by detection of all target product ions at 10 ppm tolerances. The total time of the analysis was 5 min. The calibration curve was linear in the range of 5−1000 ng/mL with interday and intraday precision levels and biases of... [more]
37213. LAPSE:2023.1917
Neutronic Study on Ac-225 Production for Cancer Therapy by (n,2n) Reaction of Ra-226 or Th-230 Using Fast Reactor Joyo
February 21, 2023 (v1)
Subject: Biosystems
Keywords: (n,2n), Ac-225, fast neutrons, fast reactor, Joyo, Ra-226, targeted alpha therapy, Th-230
Ac-225 has lately drawn considerable attention as a radioisotope for targeted alpha therapy treatment for certain types of prostate, blood-derived, and disseminated cancers, but its supply is limited. Therefore, we investigated the production method of Ac-225 by nuclear transmutation in a fast neutron reactor. The authors investigated irradiation of Ra-226 or Th-230 as a target nuclide in the experimental fast reactor Joyo, owned and operated by Japan Atomic Energy Agency, which has abundant fast neutrons and a large loading region with high heat removal capacity. Ra-226 is in increasing demand as a target nuclide to produce Ac-225. Therefore, as another option, we selected Th-230, which is 50 times more abundant than Ra-226 in natural uranium, as an alternative nuclide. Irradiation of Ra-226 and Th-230 with high energy neutrons above the threshold causes an (n,2n) reaction, producing Ra-225 and Th-229, respectively, which are the parent nuclides of Ac-225. The analyses showed that 47... [more]
37214. LAPSE:2023.1916
Combined Grey Wolf Optimizer Algorithm and Corrected Gaussian Diffusion Model in Source Term Estimation
February 21, 2023 (v1)
Subject: Optimization
Keywords: Gaussian diffusion model, Grey Wolf Optimizer (GWO), hazardous gases leakage, source term estimation (STE), swarm intelligence optimization (SIO)
It is extremely critical for an emergency response to quickly and accurately use source term estimation (STE) in the event of hazardous gas leakage. To determine the appropriate algorithm, four swarm intelligence optimization (SIO) algorithms including Gray Wolf optimizer (GWO), particle swarm optimization (PSO), genetic algorithm (GA) and ant colony optimization (ACO) are selected to be applied in STE. After calculation, all four algorithms can obtain leak source parameters. Among them, GWO and GA have similar computational efficiency, while ACO is computationally inefficient. Compared with GWO, GA and PSO, ACO requires larger population and more iterations to ensure accuracy of source parameters. Most notably, the convergence factor of GWO is self-adaptive, which is in favor of obtaining accurate results with lower population and iterations. On this basis, combination of GWO and a modified Gaussian diffusion model with surface correction factor is used to estimate the emission source... [more]
37215. LAPSE:2023.1915
Real-Time Diagnosis and Fault-Tolerant Control of a Sensor Single Fault Based on a Data-Driven Feedforward-Feedback Control System
February 21, 2023 (v1)
Subject: Process Control
Keywords: data-driven, fault diagnosis, fault-tolerant control, signal processing
Fault diagnosis is studied based on the system type, which facilitates the realization of the engineering configuration and improves the diagnosis efficiency. The fault-tolerant control method is unified based on the concept of fault compensation. According to the dynamic characteristics of the system, the method takes the boundary value of no-fault signal fluctuation as the basis for fault detection, then takes the changing intensity of the solenoid valve control signal after the fault occurs as the fault location basis. Finally, it takes the difference or ratio of the signals before and after the fault occurs as the fault estimation. For the basis of fault separation, the integral value of the fitting equation between the fault signal and time is used as the Eigenvalue of fault type separation to comprehend fault separation. A program is written in C++ and combined with MATLAB/S-Fun function to realize fault tolerance. At the same time, the dynamic model calibration and real-time fau... [more]
37216. LAPSE:2023.1914
Data Driven Model Estimation for Aerial Vehicles: A Perspective Analysis
February 21, 2023 (v1)
Subject: System Identification
Keywords: ARMAX, Box Jenkin’s, non-linear ARX, Output Error, system identification ARX, Unmanned Speed Aerial Vehicle
Unmanned Aerial Vehicles (UAVs) are important tool for various applications, including enhancing target detection accuracy in various surface-to-air and air-to-air missions. To ensure mission success of these UAVs, a robust control system is needed, which further requires well-characterized dynamic system model. This paper aims to present a consolidated framework for the estimation of an experimental UAV utilizing flight data. An elaborate estimation mechanism is proposed utilizing various model structures, such as Autoregressive Exogenous (ARX), Autoregressive Moving Average exogenous (ARMAX), Box Jenkin’s (BJ), Output Error (OE), and state-space and non-linear Autoregressive Exogenous. A perspective analysis and comparison are made to identify the salient aspects of each model structure. Model configuration with best characteristics is then identified based upon model quality parameters such as residual analysis, final prediction error, and fit percentages. Extensive validation to ev... [more]
37217. LAPSE:2023.1913
Extraction of Mathematical Correlations Applied in the Aerodynamic Separation of Solid Particles
February 21, 2023 (v1)
Subject: Process Design
Keywords: correlation coefficient, mathematical equation, Table Curve 3D
This article describes the methodology used to identify the mathematical equation that describes the correlations between the input and output parameters of an experiment. As a technological process, aerodynamic separation was chosen to represent the behavior of a solid particle within an ascending vertical airflow. The experimental data were used to identify two parameters, namely the average linear velocity and the angular velocity. The Table Curve 3D program was used to develop a mathematical equation describing the dependence between the input parameters (the shape and size of the solid particle, as well as the velocity of the airflow) and the monitored parameters. A pyramid-type analysis (following a filtering system, a general equation was determined from a large number of equations that characterize an experimental set mathematically) was designed in order to determine a single mathematical equation that describes the correlation between the input variables and those obtained as... [more]
37218. LAPSE:2023.1912
Adsorbents Used for Microcystin Removal from Water Sources: Current Knowledge and Future Prospects
February 21, 2023 (v1)
Subject: Optimization
Keywords: Adsorption, CyanoHABs, cyanotoxins, microcystins, water sources
The increasing occurrence of toxic cyanobacteria in water sources, driven by climate change and eutrophication, is of great concern worldwide today. Cyanobacterial blooms can negatively affect water bodies and generate harmful secondary metabolites, namely microcystins (MCs), which significantly impair water quality. Various adsorbents used for MC removal from water sources were assessed in this investigation. Activated carbon constitutes the most widely used adsorbent for treating contaminated waters due to its high affinity for adsorbing MCs. Alternative adsorbents have also been proposed and reported to provide higher efficiency, but the studies carried out so far in this regard are still insufficient. The mechanisms implicated in MC adsorption upon different adsorbents should be further detailed for a better optimization of the adsorption process. Certainly, adsorbent characteristics, water pH and temperature are the main factors influencing the adsorption of MCs. In this context,... [more]
37219. LAPSE:2023.1911
A CFD Investigation on the Aerosol Drug Delivery in the Mouth−Throat Airway Using a Pressurized Metered-Dose Inhaler Device
February 21, 2023 (v1)
Subject: Modelling and Simulations
Keywords: aerosol plume, Computational Fluid Dynamics, cone angle, mouth–throat geometry, particle deposition, pressurized metered-dose inhaler
Inhalation therapy involving a pressurized metered-dose inhaler (pMDI) is one of the most commonly used and effective treatment methods for patients with asthma. The purpose of this study was to develop a computational fluid dynamics (CFD) model to characterize aerosol flow issued from a pMDI into a simulated mouth−throat geometry. The effects of air flow rate and cone angle were analyzed in detail. The behaviour of the multiphase flow initiated at the inhaler actuation nozzle and extended through the mouth−throat airway was simulated based on the Eulerian-Lagrangian discrete phase model, with the k-ω model applied for turbulency. We validated our model against published experimental measurements and cover the hydrodynamic aspect of the study. The recirculation we observed at the 90° bend inside the mouth−throat airway resulted in the selective retention of larger diameter particles, and the fluid flow patterns were correlated with drug deposition behaviour. Enhancing air flow rates up... [more]
37220. LAPSE:2023.1910
A Digital Process for Manufacturing Customized Trays for Dental-Whitening Treatments
February 21, 2023 (v1)
Subject: Energy Systems
Keywords: additive technologies, bespoke dental trays, custom design, dental engineering, digital manufacturing, esthetic dentistry, tooth whitening
This study presents an alternative process for designing and manufacturing customized trays for dental-whitening treatments. The process is based on a digitized approach consisting of three main stages: design of a reference model, its manufacturing by AM, and thermoforming of the tray. The aim of the study was to develop a high-performance tray, able to guarantee comfort, safety, and efficacy for whitening treatments. To evaluate the patient’s experience, some tests under real operating conditions were performed. Twenty people carried out a nighttime treatment of 14 days. Each patient was asked to assess the overall level of satisfaction and the comfort of the tray and its ability to retain the gel. Tooth whitening was also determined according to the VITAPAN scale. All patients involved in the study were satisfied and provided positive feedback about comfort and tightness of the tray. At the end of the treatment, 15 out of 20 patients achieved shade A1 on the VITAPAN scale. The mean... [more]
37221. LAPSE:2023.1909
Priority Wise Electric Vehicle Charging for Grid Load Minimization
February 21, 2023 (v1)
Subject: Planning & Scheduling
Keywords: charging priority, electric vehicle, peak load, vehicle to grid (V2G)
The number of Electric vehicle (EV) users is expected to increase in the future. The driving profile of EV users is unpredictable, necessitating the design of charging scheduling protocols for EV charging stations servicing multiple EVs. A large EV charging load affects the grid in terms of peak load demand. Electric vehicle charging stations with solar panels can help to reduce the grid impact of EV charging events. With reference to the increasing number of EVs, new technology needs to be developed for charging station and management to create a stable system for users, and electric utilities. The load of a total EV charge can affect the grid, degrading quality and system stability. In this paper, a charging station scheduling strategy is proposed based on the game theoretic approach. In the proposed strategy, with respect to the grid load demand minimization, charging stations have scheduled EV charging times to prevent sudden peak load on the grid the proposed game theory strategy... [more]
37222. LAPSE:2023.1908
Hydrophobic Ionic Liquids for Efficient Extraction of Oil from Produced Water
February 21, 2023 (v1)
Subject: Materials
Keywords: ionic liquids, liquid–liquid extraction, oil removal, produced water
Produced water contaminated with oil has adverse effects on human health and aquatic life. Providing an efficient method for the removal of oil from produced water is a challenging task. In this study, the effects of carbon chain length and the cation nature of ionic liquids (ILs) on the removal efficiency of oil from produced water were investigated. For this purpose, seven ILs containing the bis (trifluoromethylsulfonyl) imide (NTf2) anion, and various cations such as imidazolium, pyridinium, phosphonium, and ammonium, were employed for the removal of oil from produced water via liquid−liquid extraction. The effects of process parameters such as the initial concentration of oil in produced water, contact time, pH, salinity, phase ratio, and temperature on the removal efficiency of oil were studied and optimized. 1-Decyl-3-methyl-imidazolium bis(trifluoromethylsulfonyl)imide ([C10mim][NTf2]) (IL4) was found to give the highest oil extraction efficiency of 92.8% under optimum condition... [more]
37223. LAPSE:2023.1907
Potential Use of Grape Stems and Pomaces from Two Red Grapevine Cultivars as Source of Oligosaccharides
February 21, 2023 (v1)
Subject: Optimization
Keywords: autohydrolysis, grape pomace, grape stalks, Marselan, oligosaccharides, oligosaccharides, Optimization, prebiotic sugars, response surface methodology, Touriga Nacional
Grape pomace (grape skin and seeds) and stems are major by-products of winemaking, of lignocellulosic nature. The aim of this study was to value grape pomace and stems to produce prebiotic oligosaccharides (OS). Grapes from Touriga Nacional and Marselan cultivars (Vitis vinifera L.) were used for conventional red winemaking. The total of extractives, obtained by sequential extraction with dichloromethane, ethanol, and water, was approx. 64.0% (d.w.) for both pomaces, and 46.2% and 59.5% for Marselan and Touriga Nacional stems, respectively. Lignin contents in Marselan stems (26.4%) and pomace (20.4%) were higher than in Touriga Nacional pomace (19.3%) or stems (17.3%). Polysaccharides (hemicelluloses and cellulose) represented 9 and 8.2% of Marselan and Touriga pomaces, and 22.3 and 18.7% of respective stems. After extractives removal, the pomaces and stems were submitted to a hydrothermal treatment (autohydrolysis) to release oligosaccharides from the hemicellulose fraction. Autohydro... [more]
37224. LAPSE:2023.1906
Characteristics of Ecological Energy Carriers Used in Agricultural Technology
February 21, 2023 (v1)
Subject: Environment
Keywords: atomic emission spectrometry, ecological energy carriers, ecological transmission–hydraulic fluid, environmentally sensitive environments, laboratory test equipment, working fluids
This article focuses on the properties of ecological energy carriers, which are used in agricultural and forestry technology. The aim of the article is to describe the degradation of the working fluid from the point of view of the atomic emission spectrometer, which is used for the purpose of monitoring contaminants and additive elements. The working fluid examined was Shell Naturelle HF-E 46, a universal ecological transmission−hydraulic fluid, which was tested on laboratory test equipment. The laboratory measurement was performed for 200 h, during which the gear hydraulic pump with external gearing was cyclically loaded according to the Vickers standard. The analysis of the transmission−hydraulic fluid was performed after every 50 working hours, where the analysis of the working fluid showed that there were no significant changes in the properties of the working fluid and fluid is suitable for work in agricultural and forestry machines operating in environmentally sensitive environme... [more]
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