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Records Added in July 2023
Records added in July 2023
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26. LAPSE:2023.36381
Synthesis, Molecular Docking, Molecular Dynamics Studies, and In Vitro Biological Evaluation of New Biofunctional Ketoprofen Derivatives with Different N-Containing Heterocycles
July 13, 2023 (v1)
Subject: Numerical Methods and Statistics
Keywords: 1,2,3,4-tetrahydroisoquinoline, 1,2,3,4-tetrahydroquinoline, hybrid molecules, in vitro biological activity, ketoprofen, molecular docking, molecular dynamics, piperidine, pyrrolidine
Herein, we report the synthesis of four new hybrid molecules between ketoprofen or 2-(3-benzoylphenyl)propanoic acid and N-containing heterocyclic compounds, such as piperidine, pyrrolidine, 1,2,3,4-tetrahydroquinoline, and 1,2,3,4-tetrahydroisoquinoline. The obtained hybrid compounds were fully characterized using 1H- and 13C-NMR, UV-Vis, and HRMS spectra. Detailed HRMS analysis is provided for all novel hybrid molecules. The compounds were assessed for their in vitro anti-inflammatory and antioxidant activity. The lipophilicity of the hybrids was determined, both theoretically (cLogP) and experimentally (RM). The affinity of the compounds to the human serum albumin was assessed in silico by molecular docking study using two software, and the stability of the predicted complexes was evaluated by molecular dynamics study. All novel hybrids have shown very good HPSA activity, statistically close when compared to the reference—quercetin. The molecular docking confirmed the obtained in vi... [more]
27. LAPSE:2023.36380
Development of Tea Tree Oil Based Nanoemulgel Loaded with Azithromycin for Enhancing the Antibacterial Activity
July 13, 2023 (v1)
Subject: Biosystems
Keywords: anti-bacterial activity, Azithromycin, emulgel, nanoemulgel, tea tree oil
Azithromycin (AZ) is an azalide macrolide antibiotic that is frequently employed for treating bacterial skin infections. It suffers from limited oral bioavailability, which results from incomplete absorption or extensive first-pass metabolism. Therefore, preparing azithromycin formulations for topical administration is highly recommended to avoid first-pass metabolism and to boost the concentration of the drug on the skin. The objective of our investigation was to formulate and evaluate the efficacy of AZ-loaded nanoemulgel as an antimicrobial drug. The physical appearance, spreadability, viscosity, particle size, in vitro drug release, ex vivo permeation investigations, and antimicrobial efficiency of the prepared formulations were evaluated. The prepared formulation loaded with AZ exhibited good physical quality. AZ-loaded nanoemulgel had a greater ex vivo drug permeation across rabbit skin than other formulations (AZ-loaded gel and AZ-loaded emulgel), revealing improved drug permeat... [more]
28. LAPSE:2023.36379
Optimal Control of Technological Processes
July 13, 2023 (v1)
Subject: Process Control
Keywords: features of technological objects, maximum stability of linear systems, pure delay, robustness
The paper formulates conditions under which the roots closest to the imaginary axis (critical roots) of the characteristic equation of a linearized system are real for the maximum possible degree of stability of the closed-loop control system of a technological process with pure delay. For the parameters of the controllers corresponding to the maximum degree of stability, these roots are multiples. Their multiplicity order is one more than the number of coefficients in the transfer function of the controller. It is demonstrated that for a typical technological control object, these conditions are satisfied for all “serial” control laws. This allowed for obtaining analytical expressions for optimal settings and limiting degrees of stability as functions of object parameters for typical dynamic characteristics of technological processes. The paper considers the problem of robust stability for control systems with an object containing pure delay. It has been proven that in the maximum sta... [more]
29. LAPSE:2023.36378
Effects of Bio-Coal Briquette for Residential Combustion on Brown Carbon Emission Reduction
July 13, 2023 (v1)
Subject: Environment
Keywords: bio-coal briquette, BrC, combustion, residential solid fuel
Biomass burning is an important source of brown carbon (BrC) which poses high-risk threats to human health and the environment. In this study, bio-coal briquette (coal mixed with biomass), a promising solid fuel for residential combustion, is proven to be a clean fuel which can effectively reduce BrC emission. First of all, an orthogonal experiment with three factors and three levels on the physical property of bio-briquette was carried out to identify the optimal preparation conditions including the ratio of biomass to anthracite, particle size and molding pressure. Then a combustion experiment of the bio-coal briquetted was implemented in a simulated residential combustion system. BrC emission factors (EFs) were calculated based on the detected black carbon (BC) concentration by an aethalometer, and other optical characteristics for organic components of extract samplers, such as mass absorption efficiency (MAE) and absorption angstrom index (AAE), were also explored. Lastly, composi... [more]
30. LAPSE:2023.36377
Investigation on Water Invasion Mode and Remaining Oil Utilization Rules of Fractured-Vuggy Reservoirs: A Case Study of the Intersection Region of S99 Unit in Tahe Oilfield
July 13, 2023 (v1)
Subject: Modelling and Simulations
Keywords: fractured-vuggy reservoir, numerical simulation, source-sink quantitative analysis, streamline sweep, water breakthrough mode, water invasion
Fractured-vuggy reservoirs are a new target in carbonate oil and gas exploration and development. Because of well-developed reservoir bodies, including fractures and caverns, bottom water invasion can be observed in oilfield development, with low utilization efficiency of crude oil in the reservoir. Accordingly, this study focused on the intersection region of the S99 unit of the Tahe fractured-vuggy reservoirs. Based on seismic data, the reservoir bodies can be divided into three types—caverns, fractures, and broken solution pores. Using the same location condition assignment algorithm, four single-type models are fused into a multi-scale discrete three-dimensional geological model of fractured and cavernous reservoirs, and the corresponding fractured-vuggy reservoir model was established for numerical simulation. The single-well historical fitting precision exceeded 85%. Furthermore, the development can be divided into four stages—initial stage of production, peak production stage, l... [more]
31. LAPSE:2023.36376
Latest Advances in Thermal Energy Storage for Solar Plants
July 13, 2023 (v1)
Subject: Energy Systems
Keywords: solar energy plant, storage, thermal energy system
To address the growing problem of pollution and global warming, it is necessary to steer the development of innovative technologies towards systems with minimal carbon dioxide production. Thermal storage plays a crucial role in solar systems as it bridges the gap between resource availability and energy demand, thereby enhancing the economic viability of the system and ensuring energy continuity during periods of usage. Thermal energy storage methods consist of sensible heat storage, which involves storing energy using temperature differences; latent heat storage, which utilizes the latent heat of phase change materials; and thermochemical heat storage, which utilizes reversible chemical reactions through thermochemical materials. The objective of this review paper is to explore significant research contributions that focus on practical applications and scientific aspects of thermal energy storage materials and procedures. For each type of storage, different materials have been examine... [more]
32. LAPSE:2023.36375
Experimental Investigation on Pressure-Control Characteristics of Liquid Hydrogen Tank Based on Active and Passive Thermodynamic Venting System Technology
July 13, 2023 (v1)
Subject: Process Control
Keywords: active and passive pressure control, liquid hydrogen, TVS, ullage pressure
Pressure control while minimizing the mass loss of liquid hydrogen is one of the key technologies required for the long-term storage of cryogenic propellants in microgravity in space, and the use of a thermodynamic venting system (TVS) has been considered as an effective means to solve this problem. In order to investigate the characteristics of pressure control by TVS technology, a cryogenic test platform for liquid hydrogen that integrated active and passive TVS was set up, a spray-bar exchanger and vapor-cooling screen were used to eliminate thermal stratification and realize the reuse of cold energy. Ten pressure-control tests using passive TVS (PTVS), mixing and active TVS (ATVS) strategies with heating powers of 0 W, 40 W and 80 W, were carried out. The single cycle time under different strategies, the effect of heating power on single cycle time, and the comparison of volume of the venting GH2 in different tests were analyzed in detail, the research showed that TVS technology co... [more]
33. LAPSE:2023.36374
The Application of Photovoltaic-Electric Spring Technology to Rural Power Grids
July 13, 2023 (v1)
Subject: Process Control
Keywords: electric spring, photovoltaic system, photovoltaic-grid-connected, PI control strategy, rural power, voltage fluctuations
Rural power grids are essential for rural development, impacting the lives of farmers, the agricultural economy, and the overall efficiency of agricultural production. To ensure the reliable operation of these grids, finding ways to provide high-quality power is imperative. In recent years, the penetration rate of distributed photovoltaic (PV) in the distribution network has been increasing. When the output of PV and load are not matched, the voltage fluctuation of the network affects the safe and stable operation of the distribution network. In this study, we propose that the stable operation of rural power grids can be achieved by employing a photovoltaic-electric spring (PV-ES) device. A state space model of PV-ES is established and a single PV-ES voltage control method, based on a PI controller, is proposed, taking a rural user household with a monthly power consumption of about 120 access to distributed power supply as an example. We analyzed the device’s effectiveness in addressi... [more]
34. LAPSE:2023.36373
Accelerating SARS-CoV-2 Vaccine Development: Leveraging Novel Hybrid Deep Learning Models and Bioinformatics Analysis for Epitope Selection and Classification
July 13, 2023 (v1)
Subject: Biosystems
Keywords: COVID-19, deep learning, epitope, transformers, vaccine
It is essential to use highly antigenic epitope areas, since the development of peptide vaccines heavily relies on the precise design of epitope regions that can elicit a strong immune response. Choosing epitope regions experimentally for the production of the SARS-CoV-2 vaccine can be time-consuming, costly, and labor-intensive. Scientists have created in silico prediction techniques based on machine learning to find these regions, to cut down the number of candidate epitopes that might be tested in experiments, and, as a result, to lessen the time-consuming process of their mapping. However, the tools and approaches involved continue to have low accuracy. In this work, we propose a hybrid deep learning model based on a convolutional neural network (CNN) and long short-term memory (LSTM) for the classification of peptides into epitopes or non-epitopes. Numerous transfer learning strategies were utilized, and the fine-tuned method gave the best result, with an AUC of 0.979, an f1 score... [more]
35. LAPSE:2023.36372
Effect of Freeze−Thaw Cycles on Physicochemical and Functional Properties of Ginger Starch
July 13, 2023 (v1)
Subject: Materials
Keywords: C-type crystal structure, freeze–thaw cycles, functional starch, ginger starch, oil holding capacity
Ginger (Zingiber officinale Roscoe.) starch is a waste product generated during the extraction of bioactive compounds from ginger. This study aimed to treat ginger starch with different freeze−thaw cycles and explore the effect on the functional components, physicochemical properties, and structural properties of ginger starch. The results of the study showed that as the number of freeze−thaw cycles increased, the content of resistant starch, amylose, total starch, and recrystallization in ginger starch increased significantly (p < 0.05). Freeze-dried ginger starch exhibited a C-type crystal structure in the X-ray diffraction pattern. The Fourier-transform infrared spectroscopy results also showed that the value of A1047/1022 increased, indicating that the freeze−thaw cycle would increase the degree of starch recrystallization. In terms of physical and chemical properties, compared with gelatinized starch, freeze−thawed starch had low swelling power, high solubility, low peak viscos... [more]
36. LAPSE:2023.36371
IMODBO for Optimal Dynamic Reconfiguration in Active Distribution Networks
July 13, 2023 (v1)
Subject: Energy Management
Keywords: IMODBO, K-means++, network reconfiguration, renewable energy sources, voltage fluctuations
A dynamic reconfiguration method based on the improved multi-objective dung beetle optimizer (IMODBO) is proposed to reduce the operating cost of the distribution network with distributed generation (DG) and ensure the quality of the power supply, while also minimizing the number of switch operations during dynamic reconfiguration. First, a multi-objective model of distribution network dynamic reconfiguration with the optimization goal of minimizing active power loss and voltage deviation is established. Secondly, the K-means++ clustering algorithm is used to divide the daily load of the distribution network into periods. Finally, using the IMODBO algorithm, the distribution network is reconstructed into a single period. The IMODBO algorithm uses the chaotic tent map to initialize the population, which increases the ergodicity of the initial population and solves the problem of insufficient search space. The algorithm introduces an adaptive weight factor to solve the problem of the alg... [more]
37. LAPSE:2023.36370
An Efficient and Improved Coronavirus Herd Immunity Algorithm Using Knowledge-Driven Variable Neighborhood Search for Flexible Job-Shop Scheduling Problems
July 13, 2023 (v1)
Subject: Planning & Scheduling
Keywords: adaptive mutation, coronavirus herd immunity algorithm, flexible job-shop scheduling, multi-population, variable neighborhood search
By addressing the flexible job shop scheduling problem (FJSP), this paper proposes a new type of algorithm for the FJSP. We named it the hybrid coronavirus population immunity optimization algorithm. Based on the characteristics of the problem, firstly, this paper redefined the discretized two-stage individual encoding and decoding scheme. Secondly, in order to realize the multi-scale search of the solution space, a multi-population update mechanism is designed, and a collaborative learning method is proposed to ensure the diversity of the population. Then, an adaptive mutation operation is introduced to enrich the diversity of the population, relying on the adaptive adjustment of the mutation operator to balance global search and local search capabilities. In order to realize a directional and efficient neighborhood search, this algorithm proposed a knowledge-driven variable neighborhood search strategy. Finally, the algorithm’s performance comparison experiment is carried out. The mi... [more]
38. LAPSE:2023.36369
Using Lean-and-Green Supersaturated Poly-Factorial Mini Datasets to Profile Energy Consumption Performance for an Apartment Unit
July 13, 2023 (v1)
Subject: Energy Systems
Keywords: apartment unit energy screening, energy consumption, entropic mutual information, main effect plot, partial least squares, performance improvement, supersaturated datasets
The Renovation Wave for Europe initiative aspires to materialize the progressive greening of 85−95% of the continental older building stock as part of the European Green Deal objectives to reduce emissions and energy use. To realistically predict the energy performance even for a single apartment building is a difficult problem. This is because an apartment unit is inherently a customized construction which is subject to year-round occupant use. We use a standardized energy consumption response approach to accelerate the setting-up of the problem in pertinent energy engineering terms. Nationally instituted Energy Performance Certification databases provide validated energy consumption information by taking into account an apartment unit’s specific shell characteristics along with its installed electromechanical system configuration. Such a pre-engineered framework facilitates the effect evaluation of any proposed modifications on the energy performance of a building. Treating a vast bu... [more]
39. LAPSE:2023.36368
Production Capacity Variations of Horizontal Wells in Tight Reservoirs Controlled by the Structural Characteristics of Composite Sand Bodies: Fuyu Formation in the Qian’an Area of the Songliao Basin as an Example
July 13, 2023 (v1)
Subject: Process Control
Keywords: capacity difference evaluation, composite sand body structure, control factors, Fuyu reservoir
In order to improve the combined exploitation efficiency of horizontal and vertical wells, and given the fact that the complex and varied spatial structure of sand bodies in the Fuyu oil layer in the Qian’an area of Songliao Basin leads to significant differences in production characteristics of horizontal wells, the sand body types and internal spatial structure are finely dissected according to the theory of configuration analysis, and the internal spatial structure is divided into three configuration styles: spatial clipping type, overlapping type, and separation type. Then, by comparing the productivity characteristics of horizontal wells with different configurations of sand bodies, combined with the analysis of fluid flow law under horizontal well volume fracturing, a main fracture−fracture network−matrix coupled fluid flow model in a tight reservoir based on composite sand body configuration is established. Combined with the actual volume fracturing the horizontal well area, the... [more]
40. LAPSE:2023.36367
A Novel Energy-Intensity Model Based on Time Scale for Quasi-Continuous Production in Iron and Steel Industry
July 13, 2023 (v1)
Subject: Numerical Methods and Statistics
Keywords: energy-intensity model, quasi-continuous production, time scale, workpiece valid weight
Energy intensity is an important assessment indicator of energy consumption. Unfortunately, the traditional energy intensity model (TEIM) has obvious limitations when applied to quasi- continuous production process, especially for small time scales (STS). Therefore, a novel energy intensity model (NEIM) has been established in this study. The NEIM includes three main stages. Firstly, the statistical period and time scale have been determined. Secondly, the concept of workpiece valid weight has been proposed for a given time scale. Then the specific calculation method has also been established. Thirdly, a NEIM has been suggested according to the definition of energy intensity. The application results for a reheating furnace show that the NEIM’s effectiveness has been verified via comparison with the TEIM for large time scale (LTS) and critical time scale (CTS), whereas the NEIM still has validity at STS. Additionally, calculation results for the NEIM reflect more trend information at LT... [more]
41. LAPSE:2023.36366
A Method for Predicting Surface Finish of Polylactic Acid Parts Printed Using Fused Deposition Modeling
July 13, 2023 (v1)
Subject: Optimization
Keywords: adaptive particle swarm optimization algorithm, fused deposition modeling, K-nearest neighbor algorithm, multi-category prediction, surface finish
Accurately predicting the surface finish of fused deposition modeling (FDM) parts is an important task for the engineering application of FDM technology. So far, many prediction models have been proposed by establishing a mapping relationship between printing parameters and surface roughness. Each model can work well in its specific context; however, existing prediction models cannot meet the requirements of multi-factor and multi-category prediction of surface finish and cope with imbalanced data. Aiming at these issues, a prediction method based on a combination of the adaptive particle swarm optimization and K-nearest neighbor (APSO-KNN) algorithms is proposed in this paper. Seven input variables, including nozzle diameter, layer thickness, number of perimeters, flow rate, print speed, nozzle temperature, and build orientation, are considered. The printing values of each specimen are determined using an L27 Taguchi experimental design. A total of 27 specimens are printed and experim... [more]
42. LAPSE:2023.36365
A Study of the Effect of Freeze−Thawing by Liquid Nitrogen on the Mechanical and Seepage Characteristics of Coal with Different Moisture Content Values
July 13, 2023 (v1)
Subject: Materials
Keywords: Coal, coal seams, deep low permeability, gas permeation, mechanical, seepage, water content
In order to study the effect of freezing and thawing of liquid nitrogen on the mechanical and seepage characteristics of coal rock with different water content values, conventional triaxial loading tests on freeze−thawed coal samples with different water content values were carried out using non-contact digital image processing technology. The research results showed that with the same water content, the peak strength of a liquid nitrogen freeze−thawed coal sample was smaller than that of a non-freeze−thawed coal sample, and the Poisson’s ratio was larger than that of the non-freeze−thawed coal sample; compared with the non-freeze−thawed coal sample, the strain fluctuation and concentration in the stages of compression density, elasticity, yield, and damage were weakened after freeze−thawing by liquid nitrogen, but the local stress concentration was more obvious; the non-freeze−thawed coal sample mainly showed single shear damage, and the damage fissures were inclined fissures with sma... [more]
43. LAPSE:2023.36364
CFD Simulation on Pressure Profile for Direct Contact Condensation of Steam Jet in a Narrow Pipe
July 13, 2023 (v1)
Subject: Modelling and Simulations
Keywords: direct contact condensation, dynamic pressure, pressure profile, stable steam jet, thermal hydraulic
In the published experimental results, it has been observed that when high-speed steam spurt into the subcooled waterflow, the total pressure along the axial direction at trailing edge of the steam plume shows a pressure-lift. To reveal the mechanism behind this phenomenon, this study utilizes a particle model to investigate the pressure profile of steam jet condensation in subcooled water flow in a narrow pipe. A numerical model based on the Eulerian−Eulerian multiphase model has been developed to accurately simulate the characteristics of pressure profile along the axial direction. The model’s validity is established by comparing the steam plume shape and temperature profiles with the experimental data. By analyzing the total pressure profile of the axis and the contours of gas volume fraction, it is found that there exists a pressure-lift phenomenon at trailing edge of the steam plume. The dynamic pressure of the water also shows a pressure-lift at this position, so it can be inferr... [more]
44. LAPSE:2023.36363
Reclamation Potential of Onsite Wastewater Post-Treatment with Microalgae: Chemical Elements Perspective
July 13, 2023 (v1)
Subject: Environment
Keywords: algae, circular technology, decentralized sewerage systems, fertilizer, irrigation, nature-based solutions, onsite wastewater treatment, resource recovery
Algae-based wastewater treatment is a promising technology with various applications for excess biomass such as biofertilizer production or valuable elements extraction. The benefits of the technology have been discussed for larger wastewater treatment plants (WWTPs), but the use of microalgae in decentralized wastewater treatment has been barely reported. The current study screens the possible resource recovery potential of onsite technology, which adds algae-based post-treatment to the conventional biological treatment of domestic wastewater. The effluent from the onsite sequencing batch reactor (SBR) of a household was further processed in laboratory conditions using an SBR technology with two local monocultures of algae—Klebsormidium nitens (Kützing) Lokhorst and Tetradesmus obliquus (Turpin) M. J. Wynne. The decant and the generated algal biomass were analyzed in terms of their element content. The post-treated effluent has a slightly better quality for irrigation purposes than th... [more]
45. LAPSE:2023.36362
Special Issue: Application of Proteomics and Enzyme Technologies in Foods
July 13, 2023 (v1)
Subject: Food & Agricultural Processes
This Special Issue entitled “Application of Proteomics and Enzyme Technologies in Foods” explores the latest progress and perspectives on the development and application of enzyme technologies, proteomics, and bioprocessing in the context of food science [...]
46. LAPSE:2023.36361
Fermentation of Menaquinone-7: The Influence of Environmental Factors and Storage Conditions on the Isomer Profile
July 13, 2023 (v1)
Subject: Biosystems
Keywords: bioactivity, environmental factors, Fermentation, menaquinone-7 isomer profile, storage conditions
Menaquinone-7 (MK-7) provides significant health gains due to its excellent pharmacokinetic properties. However, MK-7 occurs at low concentrations in mainstream foods, heightening the demand for nutritional supplements. MK-7 exists as geometric isomers, and only all-trans MK-7 is bioactive. Exposure to certain environments impacts the isomer profile. Knowledge of these factors and their influence on the isomer composition is important, as the efficacy of fermented MK-7 end products is solely determined by the all-trans isomer. This investigation aimed to evaluate the short- and long-term effect of atmospheric oxygen, common temperatures, and light on the isomer profile. From the short-term study, it was ascertained that MK-7 is moderately heat-stable but extremely light-sensitive. The stability of all-trans MK-7 was then examined during 8 weeks of storage at a low temperature with minimal oxygen exposure in the absence of light. Negligible change in the all-trans MK-7 concentration occ... [more]
47. LAPSE:2023.36360
A Review of the Efficiency Improvement of Hydraulic Turbines in Energy Recovery
July 13, 2023 (v1)
Subject: Energy Systems
Keywords: Box–Behnken design, efficiency, energy recovery optimization, hydraulic turbines, NSGA-II genetic algorithm
Turbine energy recovery is a process energy saving technology, and understanding turbine efficiency has important operational and economic benefits for the operator of a power plant. There are three main areas of research into turbine energy efficiency: the structural performance of the turbine itself, the configuration of the recovery device and the regulation of operating conditions. This paper summarizes recent research advances in hydraulic turbine energy efficiency improvement, focusing on the design factors that can affect the overall efficiency of a hydraulic turbine. To quantify the impact of these factors, this paper investigates the effects of surface roughness, flow rate, head and impeller speed on overall efficiency. Methods for optimizing improvements based on these design factors are reviewed, and two methods, the Box−Behnken Design method and the NSGA-II genetic algorithm, are described with practical examples to provide ideas for future research.
48. LAPSE:2023.36359
Developing a Hybrid Algorithm Based on an Equilibrium Optimizer and an Improved Backpropagation Neural Network for Fault Warning
July 13, 2023 (v1)
Subject: Process Monitoring
Keywords: BP neural network, deep learning, enhanced equilibrium optimizer, fault warning
In today’s rapidly evolving manufacturing landscape with the advent of intelligent technologies, ensuring smooth equipment operation and fostering stable business growth rely heavily on accurate early fault detection and timely maintenance. Machine learning techniques have proven to be effective in detecting faults in modern production processes. Among various machine learning algorithms, the Backpropagation (BP) neural network is a commonly used model for fault detection. However, due to the intricacies of the BP neural network training process and the challenges posed by local minima, it has certain limitations in practical applications, which hinder its ability to meet efficiency and accuracy requirements in real-world scenarios. This paper aims to optimize BP networks and develop more effective fault warning methods. The primary contribution of this research is the proposal of a novel hybrid algorithm that combines a random wandering strategy within the main loop of an equilibrium... [more]
49. LAPSE:2023.36358
Quinine: Redesigned and Rerouted
July 13, 2023 (v1)
Subject: Biosystems
Keywords: cerebral malaria, intranasal route, nanostructured lipid carriers, parasitemia reduction, quinine hydrochloride, severe malaria, solidified reverse micellar solutions
Quinine hydrochloride (QHCl) has remained a very relevant antimalarial drug 400 years after its effectiveness was discovered. Unlike other antimalarials, the development of resistance to quinine has been slow. Hence, this drug is to date still used for the treatment of severe and cerebral malaria, for malaria treatment in all trimesters of pregnancy, and in combination with doxycycline against multidrug-resistant malaria parasites. The decline in its administration over the years is mainly associated with poor tolerability due to its gastrointestinal (GIT) side effects such as cinchonism, complex dosing regimen and bitter taste, all of which result in poor compliance. Hence, our research was aimed at redesigning quinine using nanotechnology and investigating an alternative route for its administration for the treatment of malaria. QHCl nanosuspension (QHCl-NS) for intranasal administration was prepared using lipid matrices made up of solidified reverse micellar solutions (SRMS) compris... [more]
50. LAPSE:2023.36357
Numerical Simulation of Optimized Step-Wise Depressurization for Enhanced Natural Gas Hydrate Production in the Nankai Trough of Japan
July 13, 2023 (v1)
Subject: Energy Systems
Keywords: gas production, Nankai Trough, nature gas hydrate, step-wise depressurization
The utilization of natural gas hydrates as an alternative energy source has garnered significant attention due to their proven potential. Despite the successful offshore natural gas hydrate production tests, commercial exploitation has not been achieved. This study aims to enhance the understanding of gas production behavior through simulations from a single vertical well in the Nankai Trough and assess the effectiveness of the step-wise depressurization method for gas production using TOUGH + HYDRATE. The simulation results showed that the effective permeability for the water phase decreased as the hydrates were decomposed, and the invasion of the pore water from the underburden eliminated this effect. Compared with the direct depressurization method, the step-wise depressurization method significantly increased the cumulative gas production by more than 10% and mitigated the rapid generation of gas and water production during the moment of depressurization. The results also indicated... [more]