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Showing records 126 to 150 of 1263. [First] Page: 2 3 4 5 6 7 8 9 10 Last
Evaluation of Osmotic Dehydration Process in Plant Tissue with Low-Field Magnetic Resonance Imaging Enhanced with Paramagnetic Ions
Mateusz Suchanek, Zbigniew Olejniczak
November 11, 2020 (v1)
Keywords: courgette, low-field MRI, osmotic dehydration, paramagnetic contrast agent, zucchini
A novel, non-invasive low-field Magnetic Resonance Imaging (MRI) technique for studying the osmotic dehydration process in fruits and vegetables is proposed. A saturated solution of paramagnetic salt is used as both the osmotic substance and the contrast agent for MRI. Using courgette as an example, it is demonstrated that the results obtained by the new method are consistent with the standard mass transport analysis, but additional information about the spatial distribution of osmotic substance within the sample and its evolution in time is provided. The MRI method is much more efficient in terms of experiment time and the amount of biological material needed. Possible extensions of the technique to improve its accuracy are discussed.
Acid Hydrolysis of Olive Tree Leaves: Preliminary Study towards Biochemical Conversion
Soledad Mateo, Pilar Mateo, Marco Barbanera, Cinzia Buratti, Alberto J. Moya
November 11, 2020 (v1)
Keywords: characterization, hemicellulose, hydrolysis, olive tree leaves
Olive tree leaves, an abundant agricultural by-product without enough industrial market outlets, are presented in this study as a relevant resource of available carbohydrates to be chemically treated for monomeric sugar production. Characterization of two main granulometric fractions is the starting point for testing the specific effect and the relevance of three main factors (time, temperature, and sulfuric acid concentration) on diluted acid hydrolysis with respect to oligosaccharides, simple sugars, and fermentation inhibitory compounds production. The selected conditions (100 ∘ C, 90 min, and 6% w/w H 2 SO 4 ) to perform the small scale hydrolytic process, considering response surface methodology (2 3 factorial design with center points), implied production of acetic acid and hydroxymethylfurfural in concentrations not exceeding 1.10 kg m − 3 and 0.25 kg m − 3 , respectively. Thus, these experimental conditions were the reference fra... [more]
A Novel Cysteine-Functionalized MxOy Material as Support for Laccase Immobilization and a Potential Application in Decolorization of Alizarin Red S
Agnieszka Kołodziejczak-Radzimska, Teofil Jesionowski
November 11, 2020 (v1)
Subject: Biosystems
Keywords: Catalysis, decolorization, kinetic, l-cysteine, laccase, SiO2, ZrO2
Immobilization process improves the enzyme properties, like stability, activity, selectivity or specificity. In the study, a novel cysteine-functionalized MxOy (ZrO2, SiO2) material was used as a support for the immobilization of laccase from Trametes versicolor. The proposed matrix was prepared using a simple sol-gel method. The cysteine was introduced during the synthesis of a sample. Additionally, the obtained supports were modified with glutaraldehyde. The basic properties of the prepared cysteine functionalized ZrO2 and SiO2 were determined using spectroscopic, thermal, porous, electrostatic and elemental analysis. Furthermore, the obtained biocatalytic systems were used as catalysts in the oxidation of sulfonic acid. Catalytic and kinetic parameters were determined based on the proposed model reaction. Next, laccase immobilized on ZrO2- and SiO2-based materials were, for the first time, utilized in the decolorization of Alizarin Red S. In that process, the influence of duration,... [more]
A Simplified and Optimized Chemical Mechanism for Combustion of n-Pentane at Atmospheric Pressure
Zhiqun Meng, Jinggang Wang, Jiawen Qi, Chuchao Xiong, Liquan Hou, Jinghui Luo
November 11, 2020 (v1)
Keywords: atmospheric pressure, combustion, n-pentane, optimized mechanism, simplified mechanism
In the present study, the detailed mechanism of n-pentane combustion, including 697 species and 3214 reactions, is first simplified to a mechanism with only 26 species and 134 reactions, which is suitable for the pressure of 1 atm, temperatures of 1000−1600 K, and equivalent ratios of 0.5−1.6. However, when the equivalence ratio is 1.0, in the temperature range of 1000−1100 K, compared with the detailed mechanism, the maximum error of the ignition delay time predicted by the simplified mechanism exceeds 20%. Therefore, based on the method of temperature sensitivity analysis, the simplified mechanism is further utilized through reducing the A-factor of 2HO2 = H2O2 + O2 (−1) and 2HO2 = H2O2 + O2 (−2) by 10 times. By comparing with the detailed mechanism and predicting the ignition delay time, laminar flame speed, species profile, and extinction residence time, it is found that the optimized mechanism has good accuracy in the applicable range, and is fully capable of simulating the combus... [more]
Performance and Kinetics of Bioaugmentation, Biostimulation, and Natural Attenuation Processes for Bioremediation of Crude Oil-Contaminated Soils
Cevat Yaman
November 11, 2020 (v1)
Subject: Biosystems
Keywords: bioaugmentation, bioremediation, biostimulation, crude oil, first-order reaction rate model, Monod model, natural attenuation
Bioremediation of contaminated sites is usually limited due to the inadequate availability of nutrients and microorganisms. This study was conducted to assess the impact of bioaugmentation (BA) and biostimulation (BS) on petroleum hydrocarbon degradation efficiency. In addition, treatment performance and kinetics of different remediation processes were investigated. For this purpose, four tanks containing oil-contaminated soils were tested. Tank 1 was operated as the natural attenuation process. Then, a microbial inoculum and nutrients were added to tank 2 to promote BA and BS. In tank 3, only the BA process was adopted, whereas in tank 4, only the BS process was adopted. After 63 days of operation, the total petroleum hydrocarbon (TPH) in tank 2 was reduced from 1674 to 430 mg/kg, with 74% reduction. Tank 1, tank 3, and tank 4 indicated TPH reductions of 35%, 41%, and 66%, respectively. Microbiological analysis of the inoculum indicated that Alcanivorax was the dominant bacterium. The... [more]
Energy Management Strategy for Fuel Cell and Battery Hybrid Vehicle Based on Fuzzy Logic
Dongxu Li, Bing Xu, Jie Tian, Zheshu Ma
November 11, 2020 (v1)
Keywords: energy management strategy, FCHV, fuzzy logic control, powertrain system, secondary development
In order to improve fuel economy and enhance operating efficiency of fuel cell hybrid vehicles (FCHVs), fuzzy logic control (FLC) strategies are available and suggested for adoption. In this paper, the powertrain of a fuel cell hybrid vehicle is designed and the parameters of the motor, battery, and fuel cell are calculated. The FLC strategy and the power following control (PFC) strategy are designed for the studied FCHV. A secondary development for Advanced Vehicle Simulator (ADVISOR) is implemented based on the standard driving cycles, and a Chinese typical city driving cycle is imported. Simulation results demonstrate that the proposed FLC strategy is more valid and reasonable than the traditional PFC strategy. The proposed FLC strategy affects the vehicle characteristics significantly and contributes to better performance in four aspects: fuel economy, efficiency of battery and fuel cell system, battery state of charge (SOC), and battery life. Hence, the FLC strategy is more suitab... [more]
Lattice Boltzmann Simulation of Ferrofluids Film Boiling
Mohammad Yaghoub Abdollahzadeh Jamalabadi
November 11, 2020 (v1)
Keywords: boiling, ferrofluids, Lattice Boltzmann method, numerical simulation
In the present investigation, two phase film boiling of ferrofluids under an external field delivered around a two-dimensional square cross-section heater was investigated using the lattice Boltzmann technique. The purpose of this work is to find the effect of magnetic field magnitude and direction on the Nusselt number in single and double heater geometry. The improving thermal efficiency in the horizontal and vertical placement of heaters is also presented. The governing equations of mass conservation, momentum conservation, and energy conservation are solved by using a central-moments-based Lattice Boltzmann scheme. The air pocket generated around heater raised incorporating magnetic effects. The heat transfer through this advancement has been explored quantitatively and abstractly. The results shows that with the development in the volumetric applied force at the bubble-fluid interface, the bubble boundary layer thickness around the square heater lessened which cause the Nusselt nu... [more]
A Process-Based Modeling Method for Describing Production Processes of Ship Block Assembly Planning
Dongsu Jeong, Dohyun Kim, Taihun Choi, Yoonho Seo
November 9, 2020 (v1)
Keywords: block assembly planning, process-based modeling, production process, ship production, shipbuilding manufacturing
Ship block assembly planning is very complex due to the various activities and characteristics of ship production. Therefore, competitiveness in the shipbuilding industry depends on how well a company operates its ship block assembly plan. Many shipbuilders are implementing various studies to improve their competitiveness in ship block assembly planning, specifically regarding technology usage, such as modeling and simulation (M&S) and Cyber-Physical Systems (CPS). Although these technologies are successfully applied in some production planning systems, it is difficult to tailor ship production planning systems with flexibility due to unexpected situations. Providing a flexible plan for these production planning systems requires a way to describe and review the organic relationships of ship production processes. In this research, a process-based modeling (PBM) method proposes a novel approach to describing the production process of ship block assembly planning by redefining production... [more]
Green Method Synthesised Graphene-Silver Electrochemical Nanobiosensors for Ethambutol and Pyrazinamide
Rachel Fanelwa AjayI, Siphokazi Tshoko, Yonela Mgwili, Siphamandla Nqunqa, Takalani Mulaudzi, Noluthando Mayedwa, Emmanuel Iwuoha
November 9, 2020 (v1)
Subject: Biosystems
Keywords: cytochrome P450-2D6, Ethambutol, graphene oxide, pyrazinamide, silver nanoparticles, TB drug
A novel nanobiosensor was constructed with graphene oxide (GO) sheets coupled to pear extract-based green-synthesised silver nanoparticles (Ag-NPs) to which cytochrome P450-2D6 (CYP2D6) enzyme was attached. The biosensor was applied in the electrochemical detection of the tuberculosis (TB) treatment drugs, ethambutol (EMB) and pyrazinamide (PZA). The surface morphology of the green-synthesised nanocomposites was studied by performing High-Resolution Transmission Electron Microscopy (HR-TEM) and High-Resolution Scanning Electron Microscopy (HR-SEM). Fourier Transform Infrared Spectroscopy (FTIR) and Raman Spectroscopy were used for structural analysis, while Ultraviolet Visible (UV-Vis) Spectroscopy was used in the optical characterisation of the nanocomposite material. Electrochemical studies on glassy carbon electrode (GCE), which were done by Cyclic Voltammetry (CV), showed that the GO|Ag-NPs||GCE electrode was highly conductive, and thereby indicating its suitability as a platform f... [more]
CFD and Experimental Characterization of a Bioreactor: Analysis via Power Curve, Flow Patterns and k L a
Luis A. Ramírez, Edwar L. Pérez, Cesar García Díaz, Dumar Andrés Camacho Luengas, Nicolas Ratkovich, Luis H. Reyes
November 9, 2020 (v1)
Subject: Biosystems
Keywords: bioreactors, Computational Fluid Dynamics, impellers, mass transfer, oxygen diffusion, stirred tank
Mixing operations in biological processes is of utmost importance due to its effect on scaling-up and heat and mass transfer. This paper presents the characterization of a bench-top bioreactor with different impeller configurations, agitation and oxygen transfer rates, using CFD simulations and experimental procedures. Here, it is demonstrated that factors such as the type of impeller and the flow regime can drastically vary the operation as in the preparation of cultures. It was observed that the bioreactor equipped with a Rushton generates a k L a of 0.0056 s−1 for an agitation velocity and airflow rate of 250 RPM and 5 L/min, respectively. It is suitable result for the dissolved oxygen (DO) but requires a considerable amount of power consumption. It is here where the importance of the agitator’s diameter can be observed, since, in the case of the two propeller types studied, lower energy consumption can be achieved with a smaller diameter, as well as a much smaller shear c... [more]
Numerical Investigation on Coal Combustion in Ultralow CO2 Blast Furnace: Effect of Oxygen Temperature
Zhenfeng Zhou, Qiujie Yi, Ruihao Wang, Guang Wang, Chunyuan Ma
November 9, 2020 (v1)
Keywords: burnout, Coal, oxygen temperature, raceway, TGR-OBF
The cooling effect of room-temperature oxygen in oxygen blast furnaces with top gas recycling (TGR-OBF) delays the coal combustion process. To further explore the oxygen−coal combustion mechanism and intensify coal combustion in TGR-OBF, the effect of oxygen temperature on coal combustion was investigated using computational fluid dynamics (CFD). A three-dimensional model was developed to simulate the lance−blowpipe−tuyere−raceway of TGR-OBF. The effect of oxygen temperature at the same oxygen velocity and mass flow on coal combustion was investigated. Results showed the cooling effect of room-temperature oxygen was weakened, and the coal burnout was greatly increased with the increase in oxygen temperature. In particular, the coal burnout increased from 21.64% to 81.98% at the same oxygen velocity when the oxygen temperature increased from 300 to 500 K. The results provide useful reference for the development of TGR-OBF and coal combustion technology.
Effect of Cambered and Oval-Grooved Roll on the Strain Distribution During the Flat Rolling Process of a Wire
Joong-Ki Hwang
November 9, 2020 (v1)
Subject: Other
Keywords: flat-rolled wire, macroscopic shear bands, normal pressure, roll design, strain inhomogeneity
The effect of the roll design on the strain distribution of the flat surface, lateral spreading, and the strain inhomogeneity of a flat-rolled wire were investigated during the flat rolling process. Oval-grooved and cambered rolls with various radii were applied to the flat rolling process based on a numerical simulation. The effective strain on the flat surface of the wire increased when using a cambered roll due to the highly intensified contact pressure on the flat surface, while the effective strain on the flat surface of the wire decreased when using an oval-grooved roll. Lateral spreading decreased when using an oval-grooved roll because the spread in the free surface area of the wire was highly restricted by the oval-grooved roll shape. In contrast, the spread in the surface area increased when using a cambered roll due to the less-restricted metal flow at the free surface. Accordingly, a cambered roll with a small radius is highly recommended in order to improve the surface qua... [more]
Experimental Study on Pressure Distribution and Flow Coefficient of Globe Valve
Quang Khai Nguyen, Kwang Hyo Jung, Gang Nam Lee, Sung Bu Suh, Peter To
November 9, 2020 (v1)
Subject: Other
Keywords: flow coefficient, globe valve, inherent and installed characteristics, pressure distribution
In this study, the pressure distribution and flow coefficient of a globe valve are investigated with a series of experiments conducted in a flow test loop. The experiments are performed on a three-inch model test valve from an eight-inch ANSI (American National Standards Institute) B16.11—Class 2500# prototype globe valve with various pump speeds and full range of valve openings. Both inherent and installed flow characteristics are measured, and the results show that the flow coefficient depends not only on the valve geometry and valve opening but also on the Reynolds number. When the Reynolds number exceeds a certain value, the flow coefficients are stable. In addition, the pressures at different positions in the upstream and the downstream of the valve are measured and compared with recommendation per ANSI/ISA-75.01 standard. The results show that, in single-phase flow, the discrepancies in pressure between different measurement locations within close range of 10 nominal diameter fro... [more]
Extraction of Phosphorous from a Phosphorous-Containing Vanadium Titano-Magnetite Tailings by Direct Flotation
Junhui Xiao, Chao Chen, Wei Ding, Yang Peng, Tao Chen, Kai Zou
November 9, 2020 (v1)
Subject: Other
Keywords: apatite, direct flotation, phosphorous, vanadium titano-magnetite tailings
In this study, there is 1.42% P2O5 in the P-containing V-Ti magnetite tailings in Miyi Region of China, with the valuable minerals mainly including apatite, and aluminosilicate minerals as the main gangue components. The direction flotation process was used to recover phosphorous from the low-grade phosphorous-bearing V-Ti magnetite tailings. The results showed that an optimized phosphorous concentrate with a P2O5 grade of 31.35% and P2O5 recovery of 88.02% was obtained by flotation process of one roughing, three scavengings, and three cleanings under roughing conditions, which employed pulp pH of 9, grinding fineness of <0.039 mm occupying 90%, flotation concentration of 25%, and dosages of carboxymethylcellulose, oxidized paraffin wax soap, and pine oil of 400 g/t, 300 g/t, and 20 g/t, respectively. Optimized one scavenging, two scavenging, and three scavenging conditions used a pulp pH of 9, and dosages of carboxymethylcellulose, oxidized paraffin wax soap, and pine oil of 200 g/... [more]
Andrographis paniculata Extract Relieves Pain and Inflammation in Monosodium Iodoacetate-Induced Osteoarthritis and Acetic Acid-Induced Writhing in Animal Models
Donghun Lee, Chae Yun Baek, Ji Hong Hwang, Mi-Yeon Kim
November 9, 2020 (v1)
Subject: Biosystems
Keywords: analgesic, Andrographis paniculata, anti-inflammatory, osteoarthritis, pain
Osteoarthritis (OA), being the most prominent degenerative joint disease is affecting millions of elderly people worldwide. Although Andrographis paniculata is an ethnic medicine with a long history of being used as analgesic agent, no study using a monosodium iodoacetate (MIA) model has investigated its potential activities against OA. In this study, experimental OA was induced in rats with a knee injection of MIA, which represents the pathological characteristics of OA in humans. A. paniculata extract (APE) substantially reversed the loss of hind limb weight-bearing and the cartilage damage resulted from the OA induction in rats. Additionally, the levels of serum pro-inflammatory cytokines, such as IL-1β, IL-6, and TNF-α as well as the concentration of matrix metalloproteinases, including MMP-1, MMP-3, MMP-8, and MMP-13 were decreased by APE administration. Acetic acid-induced writhing responses in mice which quantitatively measure pain were significantly reduced by APE. In vitro, AP... [more]
Unsteady Flow Characteristics of Rotating Stall and Surging in a Backward Centrifugal Fan at Low Flow-Rate Conditions
Biao Zhou, Ximing He, Hui Yang, Zuchao Zhu, Yikun Wei, Yan Zhang
November 9, 2020 (v1)
Keywords: centrifugal fan, large eddy simulation, pressure fluctuation, surge, unsteady flow
The steady and unsteady flow characteristics of internal flow in a backward centrifugal fan of double inlet at low flow-rate condition are investigated by computational fluid dynamics in this paper. The investigation aims to reveal insights into generation mechanisms and our physical understanding of the rotating stall and surge. The numerical results mainly demonstrate that, with decreasing flow rate, a large number of vortex flows almost increasingly occupy the internal flow of the impeller. The reverse flow and separation vortices increasingly appear near the outlet of volute, and the internal flow of the impeller is completely blocked by the separated vortex flow at low flow-rate conditions. Results indicate that, due to a synchronization of the impeller rotation and separation vortex, these separated vortices act intensely on the pressure surface of the blade with time evolution, and the interaction between the separated vortices and surface of blade increasingly yields small-scal... [more]
Production of Liquid Milk Protein Concentrate with Antioxidant Capacity, Angiotensin Converting Enzyme Inhibitory Activity, Antibacterial Activity, and Hypoallergenic Property by Membrane Filtration and Enzymatic Modification of Proteins
Arijit Nath, Burak Atilla Eren, Attila Csighy, Klára Pásztorné-Huszár, Gabriella Kiskó, László Abrankó, Attila Tóth, Emőke Szerdahelyi, Zoltán Kovács, András Koris, Gyula Vatai
November 9, 2020 (v1)
Keywords: angiotensin converting enzyme inhibitory activity, antibacterial activity, antioxidant capacity, hypoallergenic property, liquid milk protein concentrate
Liquid milk protein concentrate with different beneficial values was prepared by membrane filtration and enzymatic modification of proteins in a sequential way. In the first step, milk protein concentrate was produced from ultra-heat-treated skimmed milk by removing milk serum as permeate. A tubular ceramic-made membrane with filtration area 5 × 10−3 m2 and pore size 5 nm, placed in a cross-flow membrane house, was adopted. Superior operational strategy in filtration process was herein: trans-membrane pressure 3 bar, retention flow rate 100 L·h−1, and implementation of a static turbulence promoter within the tubular membrane. Milk with concentrated proteins from retentate side was treated with the different concentrations of trypsin, ranging from 0.008−0.064 g·L−1 in individual batch-mode operations at temperature 40 °C for 10 min. Subsequently, inactivation of trypsin in reaction was done at a temperature of 70 °C for 30 min of incubation. Antioxidant capacity in enzyme-treated liquid... [more]
Determination of Vitamins K1, K2 MK-4, MK-7, MK-9 and D3 in Pharmaceutical Products and Dietary Supplements by TLC-Densitometry
Urszula Hubicka, Agnieszka Padiasek, Barbara Żuromska-Witek, Marek Szlósarczyk
November 9, 2020 (v1)
Keywords: dietary supplements and pharmaceutical products, quantification, TLC-densitometry, vitamin D3, vitamin K1, vitamin K2, vitamin K3
Vitamin K is a group of lipophilic molecules. Forms of vitamin K play an essential role in the activation of specific proteins involved in blood clotting cascade or bone metabolism. Another molecule belonging to the fat-soluble vitamins group that also plays an important role in calcium metabolism is vitamin D3. The dietary supplements containing vitamins K and D3 are one of the most frequently consumed by patients. The objective of this work was to develop a simple, fast and sensitive thin-layer chromatography (TLC)-densitometric procedure for the simultaneous quantitative analysis of vitamins K and D3 in pharmaceutical products and dietary supplements. The analysis of vitamins was performed on the silica gel RP-18 F₂₅₄s plates with methanol-ethanol-isopropanol in a volume ratio of 15:1:4 as a mobile phase. The densitometric measurements were made at 254 nm. The method was validated by checking the specificity, linearity, precision, recovery, limit of detection, limit of quantificatio... [more]
Development of a Freeze-Drying Stage for In-Situ µ-CT Measurements
Mathias Hilmer, Sebastian Gruber, Petra Foerst
November 9, 2020 (v1)
Keywords: freeze-drying, in-situ, lyophilization, pore network, sublimation front, X-ray, µ-CT
This paper shows the development of a freeze-drying stage for in-situ μ-CT measurements. The stage can operate in a temperature range of −40 °C up to 70 °C, and a pressure range from atmospheric pressure to 7 Pa at the sample holder. To get the best visualization of the probe, it is fundamental that the materials around the sample holder are not absorbing most of the radiation. For this reason, we built an axial symmetrical stage built out of polyetheretherketon (PEEK). A test of the stage by different freeze-drying experiments with maltodextrin and sucrose particles and solutions demonstrated its suitability to visualize the freeze-drying processes in-situ. It was possible to track the drying front during the process by radiographic and tomographic measurements, as well as to visually resolve the ice crystals and porous structure in tomographic measurements. Using different samples and process parameters, we showed that the freeze-drying stage is not only suitable for in-situ µ-CT mea... [more]
Integrated Biorefinery of Empty Fruit Bunch from Palm Oil Industries to Produce Valuable Biochemicals
Rendra Hakim Hafyan, Lupete K. Bhullar, Shuhaimi Mahadzir, Muhammad Roil Bilad, Nik Abdul Hadi Nordin, Mohd Dzul Hakim Wirzal, Zulfan Adi Putra, Gade Pandu Rangaiah, Bawadi Abdullah
November 9, 2020 (v1)
Keywords: empty fruit bunch, fuzzy analytical hierarchy process, inherent safety, integrated biorefinery, life cycle assessment, multi-objective optimization, palm oil industry, technique for order preference by similarity to ideal solution, Technoeconomic Analysis
Empty fruit bunch (EFB) utilization to produce valuable bio-chemicals is seen as an economical and sustainable alternative to waste management in palm oil industries. This work proposed an integrated biorefinery configuration of EFB valorization considering sustainability pillars—namely, economic, environmental, and safety criteria. Techno-economic analysis, life cycle assessment, and hazard identification ranking methods were used to estimate annual profit, global warming potential (GWP), fire explosion damage index (FEDI), and toxicity damage index (TDI) of the proposed integrated biorefinery. A multi-objective optimization problem was then formulated and solved for simultaneous maximization of profit and minimization of GWP, FEDI and TDI. The resulting Pareto-optimal solutions convey the trade-off among the economic, environmental, and safety performances. To choose one of these optimal solutions for implementation, a combined approach of fuzzy analytical hierarchy process and a tec... [more]
Special Issue: Application of Advanced Oxidation Processes
Ciro Bustillo-Lecompte, Jose Colina-Marquez, Lars Rehmann
November 9, 2020 (v1)
Advanced oxidation processes (AOPs) are nowadays not only considered as a complementary treatment option but as an attractive alternative to conventional methods [...]
Digital Twin for Extraction Process Design and Operation
Lukas Uhlenbrock, Christoph Jensch, Martin Tegtmeier, Jochen Strube
November 9, 2020 (v1)
Keywords: digital twin, green extraction, natural products, phytochemicals, process modeling
Traditional extraction processes of natural product are widespread, especially in regulated industries. Possibilities of extraction development and manufacturing optimization in regulated industries is limited. Regulatory approvals are often based on traditional preparations of phyto-pharmaceuticals. The dependence on traditional processes can result in sub-optimal extraction parameters causing unnecessary costs and product variability. Innovative methods like Quality-by-Design (QbD), including process analytical technology (PAT), open opportunities for manufacturers to cope with regulatory demanded, narrow batch-to-batch variability. In addition, such validated process models represent perfect digital twins which could be utilized for advanced process control and life cycle analysis.
Bioink Temperature Influence on Shear Stress, Pressure and Velocity Using Computational Simulation
J. Carlos Gómez-Blanco, Enrique Mancha-Sánchez, Alfonso C. Marcos, Manuel Matamoros, Antonio Díaz-Parralejo, J. Blas Pagador
November 9, 2020 (v1)
Keywords: bioprinting, bioprinting material, commercial bioink, computational simulation, Fluid Dynamics, level-set, temperature
Bioinks are usually cell-laden hydrogels widely studied in bioprinting performing experimental tests to tune their rheological properties, thus increasing research time and development costs. Computational Fluids Dynamics (CFD) is a powerful tool that can minimize iterations and costs simulating the material behavior using parametric changes in rheological properties under testing. Additionally, most bioinks have specific functionalities and their properties might widely change with temperature. Therefore, commercial bioinks are an excellent way to standardize bioprinting process, but they are not analyzed in detail. Therefore, the objective of this work is to study how three temperatures of the Cellink Bioink influence shear stress pressure and velocity through computational simulation. A comparison of three conical nozzles (20, 22, and 25G) for each temperature has been performed. The results show that shear stress, pressure, and velocity vary in negligible ranges for all combination... [more]
Utilization of Industry 4.0 Related Equipment in Assembly Line Balancing Procedure
Nikola Gjeldum, Bashir Salah, Amanda Aljinovic, Sajjad Khan
November 9, 2020 (v1)
Keywords: assembly line, assembly line balancing, Industry 4.0 related equipment, information and communication technology, production variety
In recent decades, production in high-volume/low-variety batches is replaced with low-volume/high-variety production type. This type of production demands excessive flows of both material and information. Recent advances in information and communication technologies (ICT), together with the concept of cyber-psychical system (CPS) enable the concept of Industry 4.0 (I4.0). In this paper, the performance of I4.0 related equipment implementation is presented in iterative assembly line balancing (ALB) process of a gearbox assembly line. Largest candidate rule method through spreadsheet simulation was used for tasks reallocations, with the objective to minimize the cycle time when the number of stations is fixed. Utilization of human analysts using snap back method for manual data gathering process still shown advantage over I4.0 equipment utilization in manual ALB. The assembly process is performed in the learning factory environment, and it is considered as very close to real industry pro... [more]
Bioavailability of Sulfur from Waste Obtained during Biogas Desulfurization and the Effect of Sulfur on Soil Acidity and Biological Activity
Monika Tabak, Aneta Lisowska, Barbara Filipek-Mazur
November 9, 2020 (v1)
Keywords: elemental sulfur, soil enzymatic activity, sulfate sulfur, sulfur pulp
Sulfur deficiency has been recognized as a limiting factor for crop production in many regions of the world. A 120-day incubation experiment was conducted to assess the effect of the applied waste elemental sulfur on sulfur bioavailability in soil. Four doses of sulfur were applied: 10, 20, 30 and 60 mg S kg−1 dry matter (d.m.) of soil. In order to assess the effect of soil pH adjustment on sulfur oxidation, the research was conducted on two sets of soil samples: one set of soil samples had natural pH, and the second one was limed before sulfur application. Application of waste sulfur slightly affected the soil pH, and increased the content of available sulfur in soil proportionally to sulfur dose. A beneficial effect of waste sulfur application on soil dehydrogenase and catalase activity was found. Liming reduced soil acidity, and significantly increased sulfate content and soil enzymatic activity. Waste elemental sulfur may be an alternative source of sulfur, supplementing the defici... [more]
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