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Records Added in April 2023
Records added in April 2023
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276. LAPSE:2023.35214
Preparation and Magneto-Structural Investigation of High-Ordered (L21 Structure) Co2MnGe Microwires
April 28, 2023 (v1)
Subject: Materials
Keywords: Heusler alloys, L21 and B2 phases structure, magneto-structural characterization, microwires, secondary phases
We used the Taylor−Ulitovsky technique to prepare nanocrystalline Co2MnGe Heusler alloy glass-coated microwires with a metallic nucleus diameter of 18 ± 0.1 µm and a total diameter of 27.2 ± 0.1 µm. Magnetic and structural studies were carried out to determine the fundamental magneto-structural characteristics of Co2MnGe glass-coated microwires. XRD revealed a well-defined nanocrystalline structure with an average grain size of about 63 nm, lattice parameter a = 5.62 and a unique mixture of L21 and B2 phases. The hysteresis loops measured at different temperatures indicated a well-known ferromagnetic behavior for the reduced remanent, where a monotonic increasing in the reduced remanent and saturation magnetization occurs. The coercivity shows anomalous behavior compared to the Co2Mn-based glass-coated microwires. The magnetization curves for field cooling and field heating (FC−FH) demonstrate a considerable dependence on the applied magnetic field, ranging from 50 Oe to 20 kOe. Intern... [more]
277. LAPSE:2023.35213
Integrated a Fused Silica Capillary Cell and In Situ Raman Spectroscopy for Determining the Solubility of CO2 in n-Decane and n-Decane + n-Hexane System
April 28, 2023 (v1)
Subject: Materials
Keywords: CO2 solubility, n-decane, n-decane + n-hexane, Raman spectroscopy
Understanding the solubility of CO2 is critical for implementing CO2-enhanced oil recovery (CO2-EOR). In this work, the solubility of CO2 in n-decane in a temperature range between 303.15 K and 353.15 K and pressures up to 15 MPa was measured using a fused silica capillary cell with in situ Raman spectroscopy. A semi-empirical CO2 solubility prediction model was obtained according to the experimental results. In order to improve the solubility of CO2 in n-decane, the solubility of CO2 in n-decane and co-solvent n-hexane (3% wt) mixture was also comparatively investigated. The results indicated that the solubility of CO2 in n-decane was 1.6355~64.0084 mol/kg. The data from the prediction model were in good agreement with the experimental data, and the mean relative deviation was 3.65%, indicating that the prediction model could be used to predict the solubility of CO2 in n-decane under different conditions. The solubility of CO2 in n-decane + n-hexane system ranged from 1.0127 mol/kg to... [more]
278. LAPSE:2023.35212
Temporal and Spatial Distribution Characteristics of Microplastics and Their Influencing Factors in the Lincheng River, Zhoushan City, China
April 28, 2023 (v1)
Subject: Environment
Keywords: basin development index, microplastics, river entering the ocean, spatial and temporal variation
Microplastics (MPs), a new type of pollutant, pose a significant threat to the environment at high concentrations. One of the primary sources of MPs in the ocean is river runoff, highlighting the need to investigate the spatial and temporal variations of MPs in rivers that flow into the sea, as well as their contributing factors. In this study, we analyzed MPs distribution and their influence factors in the Lincheng River, China. The Lincheng is the second largest river in Zhoushan island that directly flows into the ocean. MPs in the river water and sediments were detected during the wet season (July 2021), the dry season (November 2021) and the typhoon season (September 2021), and MPs were present in all reaches of the river. The abundance of MPs in the river was moderate compared to other studies, with the river water exhibiting a concentration of 15 ± 2.64 n/L and the sediment containing 318.24 ± 49.53 n/kg of MPs. In surface water, the most commonly found MP was blue man-made cell... [more]
279. LAPSE:2023.35211
A Novel Ascorbic Acid Based Natural Deep Eutectic Solvent as a Drilling Mud Additive for Shale Stabilization
April 28, 2023 (v1)
Subject: Other
Keywords: clay mineralogy, drilling fluid, ionic liquids, NADES, shale swelling
During drilling, almost 70% of wellbore instability issues result from the encountering of shale formations. Various additives such as salts, silicates, and polymers are used in water-based mud to enhance its shale-inhibition capability; however, such additives have certain limitations. Lately, ionic liquids and deep eutectic solvents (DES) have been used by various research groups as shale inhibitors in drilling fluid due to their biodegradability and efficacy. However, their popularity faded when a natural derivative of DES, i.e., Natural Deep Eutectic solvent (NADES), came into the picture. This research utilizes the in-house-prepared Ascorbic acid and Glycerine (AA:Gly)-based NADES as a drilling fluid additive for shale inhibition and compares its efficacy with counterpart inhibitors such as KCl, imidazolium-based ionic liquid, and Choline Chloride-based DES. The results show that 3% NADES improved the overall Yield point to Plastic viscosity ratio, with a 39.69% decline in mud cak... [more]
280. LAPSE:2023.35210
Flow-Induced Vibration of a Reversed U-Shaped Jumper Conveying Oil-Gas Two-Phase Flow
April 28, 2023 (v1)
Subject: Process Monitoring
Keywords: flow pattern evolution, flow-induced vibration, fluid–structure interaction, gas–liquid two-phase flow, reversed U-shaped jumper
Subsea jumpers connecting the underwater wellhead and nearby manifold commonly undergo flow-induced vibration (FIV) due to the spatially frequent alteration in the flow direction, velocity, pressure and phase volume fraction of the oil−gas two-phase flow, potentially leading to fatigue damage. This paper reports the numerical results of the FIV of a reversed U-shaped jumper excited by gas−liquid two-phase flow, which evolves from the initial slug flow with a fixed gas−liquid ratio of 1:2 when transporting through the jumper. The FIV response and flow pattern evolution are examined with a gas flow rate of Qg = 4−12 kg/s and a liquid flow rate of QL = 96−288 kg/s. When the gas−liquid flow passes through the jumper, the flow regime subsequently presents the slug flow, bubble flow, churn flow and imperfect annular flow. The out-of-plane response frequency coincides with the pressure fluctuation frequency for the four connecting bends, suggesting the fluid−structure interaction (FSI). Never... [more]
281. LAPSE:2023.35209
Optimization of Partially Hydrolyzed Polyacrylamide (HPAM) Utilized in Water-Based Mud While Drilling
April 28, 2023 (v1)
Subject: Materials
Keywords: aging, drilling mud, HPAM, Optimization, rheology, thermal aging
Water-soluble polymers are becoming increasingly important in various applications, such as stabilizer fluids and drilling muds. These materials are used as viscosifiers and filtration control agents, flocculants, and deflocculants due to their superior properties in increasing viscosity and gelling ability in the presence of crosslinkers. In general, studying the rheological behavior of drilling fluids is of paramount importance to ensure successful well drilling operations. Partially hydrolyzed polyacrylamide is one of the polymers widely used in water-based muds. The main objective of this study is to optimize the rheological properties of drilling muds through a characterization study of various parameters, including rheological behavior, viscosity, temperature (23 °C, 40 °C, and 60 °C), salinity using KCl and NaCl contents, aging, pH, solubility, and structural analysis using infrared of partially hydrolyzed polyacrylamide. The study aims to demonstrate the importance of using pol... [more]
282. LAPSE:2023.35208
Adversarial Training Collaborating Multi-Path Context Feature Aggregation Network for Maize Disease Density Prediction
April 28, 2023 (v1)
Subject: Food & Agricultural Processes
Keywords: adversarial training, context feature aggregation, maize disease, patch embedding
Maize is one of the world’s major food crops, and its yields are closely related to the sustenance of people. However, its cultivation is hampered by various diseases. Meanwhile, maize diseases are characterized by spots of varying and irregular shapes, which makes identifying them with current methods challenging. Therefore, we propose an adversarial training collaborating multi-path context feature aggregation network for maize disease density prediction. Specifically, our multi-scale patch-embedding module uses multi-scale convolution to extract feature maps of different sizes from maize images and performs a patch-embedding operation. Then, we adopt the multi-path context-feature aggregation module, which is divided into four paths to further extract detailed features and long-range information. As part of the aggregation module, the multi-scale feature-interaction operation will skillfully integrate rough and detailed features at the same feature level, thereby improving predictio... [more]
283. LAPSE:2023.35207
Extension of the Equilibrium Stage Model to Include Rigorous Liquid Holdup Calculations for Reactive Distillation
April 28, 2023 (v1)
Subject: Modelling and Simulations
Keywords: liquid holdup modelling, Reactive Distillation, reactive tray design
An extension of the equilibrium stage model to improve its applicability to reactive distillation is presented. The significant aeration of the liquid holdup on trays leads to the amount of clear liquid present being significantly less than the volume available. Tray hydraulic correlations are incorporated by leveraging the existing inside-out algorithm to rigorously calculate the liquid holdup on distillation trays, turning this parameter into an additional model output and eliminating the need to estimate this parameter beforehand. Application of this extended model shows that the aeration of the liquid holdup cannot be neglected for systems where the reaction kinetics limit the reactive productivity, and leads to column designs where additional reactive trays are needed to provide adequate reactive capacity. The workflow of this model provides a more robust path to obtaining reactive distillation column and tray designs that comply with liquid holdup requirements and tray hydraulic... [more]
284. LAPSE:2023.35206
Experimental Study on Mechanical Properties of Automatic Anchoring Preloaded Energy Absorbing Anchor Rods
April 28, 2023 (v1)
Subject: Materials
Keywords: anchor design, energy absorbing anchor, mechanical properties, roadway support, rock burst
In order to enhance the anti-impact mechanical properties of the roadway support system, an automatic anchoring pre-tightening energy absorbing anchor composed of rod body, tray, constant resistance energy absorber, energy-absorbing casing bulging block, pre-tightening force warning washer, and nut and anchorage force warning stopper was designed and developed for the special requirements of rock burst roadway support. The anchor can automatically judge the anchoring force and pre-tightening force of the anchor, and also has the functions of energy absorption and early warning. The static load tensile test and impact test are used to study the mechanical properties of the energy absorbing anchor, such as the displacement distance, energy absorption, and impact time, and they are then compared with the mechanical properties of the conventional anchor. It is concluded that under static load, the yielding distance of the energy absorbing anchor is 1.67 times that of conventional anchor. T... [more]
285. LAPSE:2023.35205
Experimental Optimization of High-Temperature-Resistant and Low Oil—Water Ratio High-Density Oil-Based Drilling Fluid
April 28, 2023 (v1)
Subject: Energy Systems
Keywords: anti-collapse, deep shale gas, high density, horizontal well, low Oil—Water ratio, oil-based drilling fluid
Problems such as well loss and collapses in deep shale gas drilling are most often due to the development of cracks in the shale formation, resulting in significant leaks of drilling fluid, the sticking and burrowing of drilling tools, and other engineering accidents. In addition, the horizontal sections of wells are very long and issues of friction, rock transport, and formation contamination loom large. As a result, the performance of drilling fluids directly affects drilling efficiency, engineering accident rates, and reservoir protection effects. We first analyze the mechanisms of each emulsifier in an oil-based drilling fluid formulation and the filtration reduction mechanisms, taking into account the collapse-prone and abnormally high-pressure characteristics of shale formations. We undertake an experimental evaluation and optimization of polymeric surfactants, such as primary and secondary emulsions for high-performance oil-based drilling fluids. The design of rigid and deformab... [more]
286. LAPSE:2023.35204
A Bootstrap-Based Tooth Surface Errors Statistics Methodology for Batch Hypoid Gears after Heat Treatment
April 28, 2023 (v1)
Subject: Numerical Methods and Statistics
Keywords: bootstrap, heat treatment, hypoid gears, statistics scheme, tooth surface errors
In the manufacturing and production of hypoid gears, it is a necessary key problem to improve the tooth surface heat treatment precision and production efficiency of the hypoid gears. How to use advanced statistical theory and methods to evaluate the whole batch machining quality of the tooth surface after heat treatment is particularly urgent. In this connection, for the same batch of hypoid gears with the same gear material, numerical control gear milling method, and heat treatment specifications, a bootstrap-based statistics scheme of tooth surface errors after heat treatment is proposed in this paper. The bootstrap statistics model of the tooth surface errors for the batch hypoid gears is established. The bootstrap probability eigenvalues and confidence intervals of the measurement sequence points on the tooth surface errors are solved, and the optimizing selection of the single sampling numbers and the repeated sampling times is completed. On this basis, by applying the cubic NURB... [more]
287. LAPSE:2023.35203
Analysis of the Influence of Micro-Pore Structure on Oil Occurrence Using Nano-CT Scanning and Nuclear Magnetic Resonance Technology: An Example from Chang 8 Tight Sandstone Reservoir, Jiyuan, Ordos Basin
April 28, 2023 (v1)
Subject: Materials
Keywords: dynamic occurrence, nano CT scanning, nuclear magnetic resonance, pore size, tight oil, tight sandstone
The micro-pore structure of a tight sandstone reservoir remarkably impacts the occurrence characteristics of the tight oil. The micro-pore structure of the Jiyuan Chang 8 tight sandstone reservoir in the Ordos Basin was examined in this research using a core physical property test, an environmental scanning electron microscope, thin section identification, and high-pressure mercury intrusion. Using nano-CT scanning and nuclear magnetic resonance technologies, representative core samples were chosen for studies evaluating the tight oil occurrence statically and dynamically. The micro-pore structure effect of a tight sandstone reservoir on the occurrence of tight oil was investigated, and the occurrence of tight oil in the reservoir forming process was discussed. It was significant to the study of tight oil in the reservoir forming process in Ordos Basin. Findings indicated that the Chang 8 reservoir in Jiyuan, Ordos Basin has poor physical properties and exhibits a high degree of hetero... [more]
288. LAPSE:2023.35202
Fixed Bed Batch Slow Pyrolysis Process for Polystyrene Waste Recycling
April 28, 2023 (v1)
Subject: Energy Systems
Keywords: plastic waste, polystyrene, pyrolysis oil, slow pyrolysis, thermochemical conversion
This study evaluates the potential of recycling polystyrene (PS) plastic wastes via a fixed bed (batch) slow pyrolysis reactor. The novelty lies in examining the reactor design, conversion parameters, and reaction kinetics to improve the process yield, activation energy, and chemical composition. PS samples were pyrolyzed at 475−575 °C for 30 min under 10−15 psi. Process yield and product attributes were evaluated using different methods to understand PS thermal degradation characteristics better. The results show that PS decomposition started within 2 min from all temperatures, and the total decomposition point of 97% at 475 °C at approximately 5 min. Additionally, analytical results indicate that the average necessary activation energy is 191 kJ/mol. Pyrolysis oil from PS was characterized by gas chromatography−mass spectrometry. The results show that styrene was produced 57−60% from all leading oil compounds (i.e., 2,4-diphenyl-1-butene, 2,4,6-triphenyl-1-hexene, and toluene), and 4... [more]
289. LAPSE:2023.35201
Reactor Temperature Control Based on Improved Fractional Order Self-Anti-Disturbance
April 28, 2023 (v1)
Subject: Process Control
Keywords: fractional order, reactor, self-disturbance control, temperature control
In the chemical industry, a reactor is an absolutely necessary container. The fact that its dynamic qualities are nonlinear and unknown, however, is what causes the temperature to deviate from the value that was specified. As a result, the typical PID control cannot fulfill the prerequisites of the production process. A new nonlinear function is presented to replace the function that was previously used, and a temperature controller that is based on better fractional order active disturbance rejection is devised. On the basis of a new fractional order temperature detector (FOTD), a new fractional order equilibrium state observer (FOESO), and nonlinear function, an improved fractional order active disturbance rejection controller has been developed. A model of the reactor was created, and the dynamic properties of temperature control were investigated. By simulation and experimentation, it was demonstrated that the strategy has a number of benefits and is effective. In this approach, th... [more]
290. LAPSE:2023.35200
Thermal-Mechanical Analysis of a Metro Station’s Concrete Structure
April 28, 2023 (v1)
Subject: Materials
Keywords: concrete structure of a metro station, cracking prediction, temperature stress, thermal-mechanical analysis
The problem of temperature variation in mass concrete construction is a crucial problem in civil engineering. The problems of the temperature field, damaged areas, and the cracking of the structure during the construction process of concrete pouring are analyzed in this paper. An elastic and damaged constitutive model for concrete and a fully coupled analysis method for analyzing the temperature-stress field was proposed to simulate and predict the construction process of a concrete structure in a metro station. The influence of different concrete compositions and material properties was not taken into account in this study. The results show that the temperature-stress complete coupling analysis method can be applied to the calculation and analysis of cracking in a concrete structure that is caused by internal temperature variations during the pouring process of complex concrete structures. An efficient method and research approach is proposed by this study to analyze the damage and cr... [more]
291. LAPSE:2023.35199
Comparison Study on the Water-to-Biomass Ratio in Hydrothermal Carbonization of Fresh Seaweed
April 28, 2023 (v1)
Subject: Materials
Keywords: Biomass, hydrochar, moisture content, waste seaweed, water to biomass ratio
Upgrading wet biomass to char via hydrothermal carbonization is a promising method to produce valuable resources for adsorption of organic impurities. In this work, a fresh green seaweed, Ulva pertusa, was investigated to demonstrate the effects of pre-drying and pre-washing on the process and the hydrochar production. Surface moisture and bound moisture were found to affect this process. Hydrochar produced from fresh seaweed with additional water showed similar adsorption capacity to fresh seaweed without additional water and 38% higher than hydrochar from soaked dry seaweed. This was supported by FTIR spectra analysis, which showed that these hydrochars produced from fresh seaweed without additional water have the highest proportion of carboxyl functional groups.
292. LAPSE:2023.35198
Textural, Rheological, and Sensory Modifications in Oaxaca Cheese Made with Ultrasonicated Raw Milk
April 28, 2023 (v1)
Subject: Materials
Keywords: high-intensity ultrasound, microstructure, Oaxaca cheese, sensory acceptability, textural properties
In this research, we evaluated the effects of different frequencies (25 and 45 kHz) and times (15 and 30 min) of high-intensity ultrasound (HIU) applied to fresh raw milk on the textural properties of Oaxaca cheese. When HIU was applied for 15 min, the cheese melting time was reduced by up to 23.4 s compared to the control. The cheeses produced with ultrasonicated milk at 45 kHz presented larger melting and exudate areas. They were softer, but consumer acceptability was lower. Frequencies of 25 and 45 kHz (15 or 30 min) reduced the temperature of the solid−liquid transition by 1.9−3.6 °C and 0.6−1.8 °C, respectively, compared to controls. Consequently, the melting time in ultrasonicated cheese was significantly reduced. The strands were perfectly aligned and well organized in the direction of stretching with 25 kHz ultrasonication. In addition, these cheeses were more consistent, chewy, and rubbery. Consequently, they were preferred and more accepted in flavor, aroma, and texture, with... [more]
293. LAPSE:2023.35197
Thermal Stability, Kinetic Analysis, and Safe Temperature Assessment of Ionic Liquids 1-Benzyl-3-Methylimidazolium Bis (Trifluoromethylsulfonyl) Imide for Emerging Building and Energy Related Field
April 28, 2023 (v1)
Subject: Materials
Keywords: building polymer, green solvents, thermal hazard, thermochemical reactivity, thermogravimetric analysis
Ionic liquids are molten salts that possess excellent chemical and thermal stability. Due to their inherent qualities in green chemistry, ionic liquids have been identified as potential substitutes for traditional organic solvents. These useful physical and chemical properties lead to some promising applications in fields such as building polymer engineering alternative materials and renewable energy technologies. Although they are classified as green solvents, these new solvents exist in a high-temperature environment, which is related to thermochemical reactivity and safety; there are few related studies. To analyze the possible high-temperature application environment of ionic liquids in the future, we analyzed the new ionic liquid 1-Benzyl-3-methylimidILlium bis (trifluoromethylsulfonyl) imide ([BZMIM][TF2N]), which lacks thermal analysis basis. This study used thermogravimetric analysis as the basis of the reaction model. We calculated the thermal hazard, kinetics, and parameter a... [more]
294. LAPSE:2023.35196
Pore Distribution Characteristics of Different Lithofacies Shales: Evidence from Scanning Electron Microscopy
April 28, 2023 (v1)
Subject: Materials
Keywords: Dongying Sag, lacustrine shale, pore morphology, pore size, scanning electron microscopy
To disclose the pore distribution characteristics of different lithofacies lacustrine shales, ten samples collected from the Shahejie Formation, Dongying Sag, Bohai Bay Basin, China, were examined using argon ion beam milling−scanning electron microscopy (SEM). A quantitative method was adopted to characterize shale pore distributions based on the SEM images. Mercury intrusion capillary pressure was employed to determine the pore throat size distributions of the shales. The SEM images indicated that in shale reservoirs, interparticle pores at the edges of brittle particles and intraparticle pores in clay mineral aggregates primarily contribute to the reservoir spaces and that in calcite-rich shales, dissolution pores provide secondary reservoir space. Among the morphologies of dissolution, intraparticle, and interparticle pores, the morphology of the dissolution pores is the simplest, followed by those of intraparticle and interparticle pores in that order. Clay and felsic minerals pri... [more]
295. LAPSE:2023.35195
Microstructure, Wear Resistance and Corrosion Performance of Inconel 625 Layer Fabricated by Laser/Ultra-High Frequency (UHF) Induction Hybrid Deposition
April 28, 2023 (v1)
Subject: Materials
Keywords: corrosion resistance, laser deposition, microstructure, ultra-high frequency (UHF) induction heat, wear resistance
In order to avoid microstructure degradation caused by low frequency induction heat in laser-induction hybrid deposition, this paper proposes a laser/ultra-high frequency (UHF) induction hybrid deposition method. Microstructure observation is carried out to reveal the effect of UHF induction heat on the microstructure of the deposited layer. Results indicate that the laser-UHF induction hybrid deposited layer, under a current density of 1.14 × 108 A/m2, exhibits a finer microstructure and fewer Laves phases than that of the laser deposited layer. As the current density increases from 1.01 × 108 A/m2 to 1.14 × 108 A/m2, the microstructure of the laser-UHF induction hybrid deposited layer is significantly refined; however, as the current density further increases, the microstructure is only slightly further refined, since the enhanced thermal effect, along with the increasing current density, may help grain growth. Wear test demonstrates that the laser-UHF induction hybrid deposited laye... [more]
296. LAPSE:2023.35194
Techniques Used for Bond Strengthening of Sub-Standard Splices in Concrete: A Review Study
April 28, 2023 (v1)
Subject: Process Design
Keywords: bond failure, bond strength, bonded length, CFRP, confinement, insufficient lap splice length, jacketing, RC members, review, strengthening methods, UHPC
Bar splicing is considered an essential part of the construction process of reinforced concrete (RC) due to the ease of installation in construction, transportation constraints, and restricted length of reinforcing bars. Splices serve the primary role of joining reinforcement bars in standard RC elements such as columns, walls, beams, slabs, and joints. Bond behavior between the bars and the concrete is one of the fundamental qualities required for appropriate RC structure design and analysis, as it affects serviceability and ultimate limit states. The most common failure found in lap splice locations is debonding, which occurs at the splice region and insufficient lapped length is considered as the primary cause because of design or construction mistakes, design by outmoded code, and natural catastrophes. As a result, strengthening existing substandard splices in RC structures is critical. The purpose of this research is to analyze and summarize experimental strengthening solutions fo... [more]
297. LAPSE:2023.35193
Hydroxypropyl-β-Cyclodextrin-Glycerol-Assisted Extraction of Phenolics from Satureja montana L.: Optimization, Anti-Elastase and Anti-Hyaluronidase Properties of the Extracts
April 28, 2023 (v1)
Subject: Biosystems
Keywords: cosmeceutical extracts, cyclodextrin-glycerol-assisted extraction, luteolin-7-O-glucoside, rosmarinic acid, Satureja montana, ultrasound-assisted extraction
A green method for hydroxypropyl-β-cyclodextrin-glycerol-assisted extraction (HCGAE) of bioactive phenolics from S. montana, Lamiaceae was optimized using Box-Behnken design and response surface methodology and compared conventional water/ethanol-based extraction. The procedure was aimed at obtaining extracts with the maximum content of total phenols (TP), flavonoids (TF), dihydroxycinnamic acids (TDCA), rosmarinic acid (RA), and luteolin 7-O-glucoside (LG). The impact of glycerol content (0−70%), 2-hydroxypropyl-β-cyclodextrin content (0−0.4 mmol), temperature (20−70 °C), herbal material weight (0.3−0.8 g), extraction duration (5−25 min), and ultrasound power (144−720 W) on the extraction efficiency was analyzed. Four extracts with maximum amounts of target phenols, OPT-TP (5.93 mg/mL), OPT-TDCA-RA (4.17 mg/mL and 1.16 mg/mL, respectively), OPT-TF (0.99 mg/mL), and OPT-LG (0.28 mg/mL) were prepared. Comparison of the content of TDCA, TF, RA, and LG with those obtained in water/ethanol... [more]
298. LAPSE:2023.35192
Benefits and Limitations of Artificial Neural Networks in Process Chromatography Design and Operation
April 28, 2023 (v1)
Subject: Materials
Keywords: artificial neural networks, chromatography modeling, hybrid models, Machine Learning, mixed-mode chromatography, parameter estimation
Due to the progressive digitalization of the industry, more and more data is available not only as digitally stored data but also as online data via standardized interfaces. This not only leads to further improvements in process modeling through more data but also opens up the possibility of linking process models with online data of the process plants. As a result, digital representations of the processes emerge, which are called Digital Twins. To further improve these Digital Twins, process models in general, and the challenging process design and development task itself, the new data availability is paired with recent advancements in the field of machine learning. This paper presents a case study of an ANN for the parameter estimation of a Steric Mass Action (SMA)-based mixed-mode chromatography model. The results are used to exemplify, discuss, and point out the effort/benefit balance of ANN. To set the results in a wider context, the results and use cases of other working groups a... [more]
299. LAPSE:2023.35191
On the Energy Performance and Energy Saving Potential of the Pharmaceutical Industry: A Study Based on the Italian Energy Audits
April 28, 2023 (v1)
Subject: Energy Policy
Keywords: energy audits (EAs), Energy Efficiency, energy management, energy performance improvement actions (EPIA), energy performance indicators (EnPI), energy transition, pharmaceutical industry, specific energy consumption (SEC)
The growing attention towards environmental sustainability in the pharmaceutical industry and increased awareness of the potential for improving energy performance are justified by the fact that the sector is energy intensive. However, the variety of the processes and the lack of data about production and energy consumption make it difficult to calculate Energy Performance Indicators (EnPIs) as much as to list Energy Performance Improvements Actions (EPIAs). This work elaborates data, such as final energy consumption and site characteristics, from 84 mandatory Italian Energy Audits (EAs) to calculate the mean and standard deviation of site-level EnPIs. Additionally, the suggested and implemented EPIAs are analyzed to describe achieved and potential savings. The results show what follows. In the typical pharmaceutical plant, around 70% of energy is used in auxiliary services, and its use is not related to production. For this reason, EnPIs calculated both with respect to mass production... [more]
300. LAPSE:2023.35190
Combustion Chamber Optimization for Dual-Fuel Biogas−Diesel Co-Combustion in Compression Ignition Engines
April 28, 2023 (v1)
Subject: Modelling and Simulations
Keywords: 3D-CFD analysis, biogas, bowl optimization, dual fuel, injection, micro-cogeneration
Micro-cogeneration with locally produced biogas from waste is a proven technique for supporting the decarbonization process. However, the strongly variable composition of biogas can make its use in internal combustion engines quite challenging. Dual-fuel engines offer advantages over conventional SI and diesel engines, but there are still issues to be addressed, such as the low-load thermodynamic efficiency and nitrogen oxide emissions. In particular, it is highly desirable to reduce NOx directly in the combustion chamber in order to avoid expensive after-treatment systems. This study analyzed the influence of the combustion system, especially the piston bowl geometry and the injector nozzle, on the performance and emissions of a dual-fuel diesel−biogas engine designed for micro-cogeneration (maximum electric power: 50 kW). In detail, four different cylindrical piston bowls characterized by radii of 23, 28, 33 and 38 mm were compared with a conventional omega-shaped diesel bowl. Moreov... [more]

