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Records added in 2020
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Showing records 51 to 75 of 1263. [First] Page: 1 2 3 4 5 6 7 Last
Heat and Mass Transfer during Lignocellulosic Biomass Torrefaction: Contributions from the Major Components—Cellulose, Hemicellulose, and Lignin
Ken-ichiro Tanoue, Kentaro Hikasa, Yuuki Hamaoka, Akihiro Yoshinaga, Tatsuo Nishimura, Yoshimitsu Uemura, Akihiro Hideno
December 17, 2020 (v1)
Keywords: biomass major components, biomass torrefaction, numerical simulation, packed bed reactor, reaction enthalpy
The torrefaction of three representative types of biomass—bamboo, and Douglas fir and its bark—was carried out in a cylindrical-shaped packed bed reactor under nitrogen flow at 573 K of the reactor wall temperature. As the thermal energy for the torrefaction was supplied from the top and the side of the bed, the propagation of the temperature profile of the bed is a crucial factor for discussing and improving the torrefaction reactor performance. Therefore, the temperature and gas flow rate (vector) profiles throughout the bed were calculated by model simulation so as to scrutinize this point. The measured temperature at a certain representative location (z = 30 mm and r = 38 mm) of the bed was well reproduced by the simulation. The volume faction of the bed at temperatures higher than 500 K at 75 min was 0.89, 0.85, and 0.99 for bamboo, and Douglas fir and its bark, respectively. It was found that the effective thermal conductivity is the determining factor for this difference. The he... [more]
Investigation on Unsteady Flow Characteristics in an Axial-Flow Fan under Stall Conditions
Chenlong Jiang, Mengjiao Li, Enda Li, Xingye Zhu
December 17, 2020 (v1)
Keywords: axial-flow fan, incidence angle, modal and spike disturbance, rotating stall, unsteady flow characteristics, wavelet analysis
Based on Shear Stress Transport (SST) turbulence model for unsteady simulation of an axial-flow fan, this paper studies the time-frequency information in the hump region, and investigates the disturbance information of spike and modal wave under different flow coefficients based on continuous wavelet transform (CWT). The results show that before the hump point, the low-frequency modal wave occupies the main disturbance form and circularly propagates at 1/10 of the rotor speed, and the axial-flow fan does not enter the stall stage; while after the flow coefficient reduces to the hump point, the spike wave with higher frequency replaces the modal wave as the main disturbance mode while the axial-flow fan enters the stall stage. Through in-depth investigation of unsteady flow characteristics under the hump point, it is found that after experiencing the emerging spike, with the sharp increase of incidence angle, some flow distortions appear on the intake surface, and further induce some fl... [more]
Evaluation of Postharvest Processing of Hazelnut Kernel Oil Extraction Using Uniaxial Pressure and Organic Solvent
Gürkan Alp Kağan Gürdil, Abraham Kabutey, Kemal Çağatay Selvi, Čestmír Mizera, David Herák, Adéla Fraňková
December 17, 2020 (v1)
Keywords: bulk hazelnut kernels, heating temperature, mechanical properties, oil efficiency, relaxation process
Uniaxial loading and organic solvent are small-scale oil expression methods used to evaluate the mechanical behavior, oil content, and oil efficiency of oil-bearing materials aimed at designing a low-cost mechanical pressing system. Bulk kernels of pressing height 40 mm were heated from 40 to 60 °C and compressed at maximum force of 60 kN and speeds from 4 to 8 mm/min. Relaxation times between 3 and 12 min were applied to assess the kernel oil efficiency. The kernel oil point was identified at deformation levels between 15 and 25 mm at a speed of 4 mm/min using a litmus test. The kernel oil was analyzed for peroxide value and free fatty acid. Kernel oil content was determined by Soxhlet extraction. Increased speed caused a serration effect on the force−deformation curve leading to lower oil yield. Lower and upper oil point forces at 6.21 ± 0.58 and 10.61 ± 0.71 kN were observed to be useful for predicting the pressure for maximum output oil. The peroxide value and free fatty acid conte... [more]
Application of Theoretical and Experimental Findings for Optimization of Mixing Processes and Equipment
Tomáš Jirout, Dita Jiroutová
December 17, 2020 (v1)
Keywords: agitator, blending, hydrofoil impeller, impeller efficiency, Mixing, particle suspension, pumping capacity
The homogenization of the agitated batch and ensuring the suspension of particles are the most frequently encountered requirements in terms of mixing applications. These operations are affected by the flow of the agitated batch. The geometrical parameters of the mixing system, especially the shape of the agitator blade, affect flow and circulation in the agitated batch. The present work provides a general description of the most common processes in the agitated batch (blending and particle suspension), hydrodynamic parameters (flow in agitated batches, pumping and circulation capacity of impellers) and the geometrical configurations of the mixing equipment (shape of vessel, baffle and impeller, and their mutual arrangement) that influence the process. The dimensionless process characteristics of the agitator were derived by theoretical analysis. These characteristics were applied to evaluate an extensive set of experimental data with various geometric configurations of the mixing equip... [more]
An Overview of Natural Extracts with Antioxidant Activity for the Improvement of the Oxidative Stability and Shelf Life of Edible Oils
Francesca Blasi, Lina Cossignani
December 17, 2020 (v1)
Keywords: edible oils, natural antioxidants, oxidative stability, shelf life, vegetable extracts, waste
Many plant materials, such as fruits and vegetables as well as herbs and spices, represent valuable sources of antioxidants. In recent years, wastes from agriculture and food industrial processes have been shown to be interesting sources for bioactive compound recovery, strongly contributing to the circular economy. Nowadays, because of their possible adverse effects on human health, there is a tendency to replace synthetic antioxidants with natural compounds. This review attempts to critically summarize the current evidence on plant bioactives, extracted from food or waste, added to unsaturated vegetable oils, in order to obtain high added-value products and to ameliorate their oxidative stability and shelf life. The goal of this review is to demonstrate the current status of the research on edible oils added with natural plant bioactives, highlighting new approaches in the field of health-promoting foods.
A Study to Investigate the Mechanical Properties of Recycled Carbon Fibre/Glass Fibre-Reinforced Epoxy Composites Using a Novel Thermal Recycling Process
Sankar Karuppannan Gopalraj, Timo Kärki
December 17, 2020 (v1)
Subject: Materials
Keywords: carbon fibre, compression moulding, glass fibre, manufacturing waste, mechanical properties, thermal recycling
Manufacturing-based carbon fibre-reinforced polymer (CFRP) and glass fibre-reinforced polymer (GFRP) wastes (pre-consumer waste) were recycled to recover valuable carbon fibres (CFs) and glass fibres (GFs), utilising a novel thermal recycling process with a cone calorimeter setup. The ideal conditions to recycle both the fibres occurred at 550 °C in atmospheric pressure. The processing time in the batch reactor to recycle CFs was 20−25 min, and to recycle GFs it was 25−30 min. The recovery rate of the recycled CFs was 95−98 wt%, and for GFs it was 80−82 wt%. Both the recycled fibres possessed a 100−110 mm average length. The resin phase elimination was verified by employing scanning electron microscopy (SEM). Furthermore, the fibres were manually realigned, compression moulded at room temperature, and cured for 24 h by a laminating epoxy resin system. The newly manufactured CFRP and GFRP composites were continuous (uniform length from end to end), unidirectionally oriented (0°), and no... [more]
Online High Performance Genetic Algorithm Based Sliding Mode Control for Controllable Pitch Propeller
Yuchao Wang, Qiusu Wang, Huixuan Fu
December 17, 2020 (v1)
Keywords: chattering-free, controllable pitch propeller, high-performance genetic algorithm, real-time, sliding mode control
During the voyage of a ship, the performance of a controllable pitch propeller (CPP) is severely affected by the changing load demand and ever-present disturbance from ocean waves, which will also result in model uncertainty. In order to improve the performance of the CPP system, an online high-performance genetic algorithm (HPGA)-based sliding mode control (SMC) strategy is proposed. Firstly, the model of the CPP system is obtained according to the manufacturer’s instructions. Then, a chattering-free sliding mode controller (CF-SMC) is designed for the CPP system, after which the parameters in the CF-SMC are optimized with the HPGA method. Finally, the optimized CF-SMC is applied to an experimental setup of a prototype CPP system. In order to validate the effectiveness of the proposed method, it is compared with a proportional-integral-derivative (PID) controller, which is typically applied on real CPP-systems, with results indicating the superiority of the proposed method.
Integrated Control Policy for a Multiple Machines and Multiple Product Types Manufacturing System Production Process with Uncertain Fault
Jia You, Ming Li, Kai Guo, Hao Li
December 17, 2020 (v1)
Keywords: manufacturing system, multiple machines and multiple product types, optimal production control, prioritized hedging point policy, process diagnostics, production capacity planning, uncertain fault
The optimization of production cost has always been a key issue in manufacturing systems; for the single product type manufacturing systems, lots of research studies have proved the validity of the hedging point control policy in production cost control. However, due to the complexity of the multiple machines and multiple product types manufacturing systems with uncertain fault, it is difficult to achieve a good control effect only by using the hedging point control policy. To optimize the total production cost under constantly changing demands, an integrated control policy that combines the prioritized hedging point (PHP) control policy with the production capacity planning during production is proposed, and the decision variables are obtained by a particle swarm optimization (PSO) algorithm. The simulation experiments show the effectiveness of the proposed integrated control policy in production cost control for the multiple machines and multiple product types manufacturing system.
Application of Systems Engineering Principles and Techniques in Biological Big Data Analytics: A Review
Q. Peter He, Jin Wang
December 17, 2020 (v1)
Keywords: biological big data, dynamic analysis, feature engineering, Machine Learning, overfitting, systems engineering
In the past few decades, we have witnessed tremendous advancements in biology, life sciences and healthcare. These advancements are due in no small part to the big data made available by various high-throughput technologies, the ever-advancing computing power, and the algorithmic advancements in machine learning. Specifically, big data analytics such as statistical and machine learning has become an essential tool in these rapidly developing fields. As a result, the subject has drawn increased attention and many review papers have been published in just the past few years on the subject. Different from all existing reviews, this work focuses on the application of systems, engineering principles and techniques in addressing some of the common challenges in big data analytics for biological, biomedical and healthcare applications. Specifically, this review focuses on the following three key areas in biological big data analytics where systems engineering principles and techniques have be... [more]
A Novel Approach for Predicting the Height of Water-Conducting Fracture Zone under the High Overburden Caving Strength Based on Optimized Processes
Tao Hu, Gongyu Hou, Su Bu, Zhen Zhu, Yan Wang, Ziyi Hu, Zixiang Li
December 17, 2020 (v1)
Subject: Other
Keywords: approach based on optimized processes, Brillouin optical time-domain reflectometry (BOTDR), high overburden caving strength, optical fiber strain, overburden, water-conducting fracture zone (WCFZ)
The height of water-conducting fracture zones (WCFZs) is vital for the prevention of water, gas, and roof accidents in coal mines. However, its dynamic evolution law and maximum height are difficult to be obtained by traditional prediction methods, especially for conditions in which there is high overburden caving strength and a thick coal seam. Therefore, taking the 150,313 fully mechanized caving working face in Yingying Coal Mine as a background, according to the principle of optimized processes, a new predicting approach based on the Brillouin optical time-domain reflectometry (BOTDR) is proposed. Firstly, we estimated the height through empirical formula calculation, theoretical analysis, and similar model simulation tests. Secondly, we studied the optimized layout of optical cables in the overburden in detail for predicting the maximum height of the WCFZ and keeping the cables in good performance during field prediction. Thirdly, we researched and optimized the borehole parameter... [more]
Analysis of Chemical and Biochemical Parameters of Petrol-Contaminated Soil after Biostimulation with an Enzyme Reagent
Kornel Curyło, Arkadiusz Telesiński, Grzegorz Jarnuszewski, Teresa Krzyśko-Łupicka, Krystyna Cybulska
December 17, 2020 (v1)
Keywords: dehydrogenases, Fyre-Zyme, hydrocarbons, nitrogen total, organic carbon, phosphatases, soil remediation
This study aimed to assess the effect of petrol and the Fyre Zyme reagent on selected chemical and biochemical properties of loamy sand. The experiment was conducted under laboratory conditions. First, petrol was introduced into the soil at doses of 0 and 50 g k−1dry matter (DM). Next, 6% Fyre-Zyme enzyme reagent solution was added to the samples contaminated and uncontaminated with petrol, in the following combinations: 0 (control), once at 40 cm3 kg−1 DM, twice at 20 cm3 kg−1 DM at two-week intervals, and four times at 10 cm3 kg−1 DM at weekly intervals. Contamination of loamy sand with petrol caused slight changes in the determined chemical parameters and stimulated dehydrogenase activities, but inhibited the activity of phosphatases. The introduction of the enzyme reagent into the soil increased the Corg and Ntot content. The greatest changes were observed in the activity of phosphatases. The receiver operating characteristic (ROC) curves revealed that the application of the enzyme... [more]
The Evolution of Biodiesel Policies in China over the Period 2000−2019
Chao-chen Chung, Yapeng Zhang, Lina Liu, Yixuan Wang, Ziji Wei
December 17, 2020 (v1)
Subject: Energy Policy
Keywords: biodiesel, China, content analysis, policy, policy transitions
The Chinese government launched policies supporting biodiesel production and innovation to meet sustainable energy demands under rapid economic and social development. This study systematically investigates the dynamic transitions of biodiesel policies in China regarding policy contents and policy networks. We performed a content analysis in this study and used NVivo12 software to support the analysis process. The results highlighted some issues. First, the Chinese government supported the development of biodiesel from multiple policy objectives and adopted various policy instruments, eventually transforming biodiesel in China from the first- to second-generation. Second, the State Council was the main institution to promote biodiesel policies, and the National Development and Reform Commission under the State Council burdened most of the responsibilities of policy implementation. Most of the policies were issued at a lower level of administration rather than a higher level of decision... [more]
A Comparison of “Bottom-Up” and “Top-Down” Approaches to the Synthesis of Pt/C Electrocatalysts
Alexandra Kuriganova, Nikita Faddeev, Mikhail Gorshenkov, Dmitri Kuznetsov, Igor Leontyev, Nina Smirnova
December 17, 2020 (v1)
Subject: Materials
Keywords: alternating current, electrocatalysis, electrochemical dispersion, ethanol electrooxidation, fuel cell, nanoparticles, platinum catalyst, polyol process, synthesis method
Three 40 wt % Pt/C electrocatalysts prepared using two different approaches—the polyol process and electrochemical dispersion of platinum under pulse alternating current—and a commercial Pt/C catalyst (Johnson Matthey prod.) were examined via X-ray diffraction (XRD) and transmission electron microscopy (TEM). The stability characteristics of the Pt/C catalysts were studied via long-term cycling, revealing that, for all cycling modes, the best stability was achieved for the Pt/C catalyst with the largest platinum nanoparticle sizes, which was synthesized via electrochemical dispersion of platinum under pulse alternating current. Our results show that the mass and specific electrocatalytic activities of Pt/C catalysts toward ethanol electrooxidation are determined by the value of the electrochemically active Pt surface area in the catalysts.
Magnetic Nanoparticles of Fe3O4 Biosynthesized by Cnicus benedictus Extract: Photocatalytic Study of Organic Dye Degradation and Antibacterial Behavior
Álvaro de Jesús Ruíz-Baltazar, Nestor Méndez-Lozano, Daniel Larrañaga-Ordáz, Simón Yobanny Reyes-López, Marco Antonio Zamora Antuñano, Ramiro Pérez Campos
December 17, 2020 (v1)
Subject: Materials
Keywords: iron oxides, nanoparticles, organic dye degradation, photocatalytic effect antibacterial behavior
Currently, the use of sustainable chemistry as an ecological alternative for the generation of products or processes that are free of a polluting substance has assumed a preponderant role. The aim of this work is to propose a bioinspired, facile, low cost, non-toxic, and environmentally friendly alternative to obtaining magnetic nanoparticles with a majority phase of magnetite (Fe3O4). It is important to emphasize that the synthesis was based on the chemical reduction through the Cnicus benedictus extract, whose use as reducing agent has not been reported in the synthesis of iron oxides nanoparticles. In addition, the Cnicus benedictus is an abundant endemic plant in Mexico with several medicinal properties and a large number of natural antioxidants. The obtained nanoparticles exhibited significant magnetic and antibacterial properties and an enhanced photocatalytic activity. The crystallite size of the Fe3O4 nanoparticles (Fe3O4 NP’s) was calculated by the Williamson-Hall method. The... [more]
Design, Cost Estimation and Sensitivity Analysis for a Production Process of Activated Carbon from Waste Nutshells by Physical Activation
Marcelo León, Javier Silva, Samuel Carrasco, Nelson Barrientos
December 17, 2020 (v1)
Keywords: activated carbon, economic evaluation, nutshell waste, production cost
A conceptual design of an industrial production plant for activated carbon was developed to process 31.25 tons/day of industrial waste nutshells as the raw material and produce 6.6 ton/day of activated carbon using steam as an activation agent. The design considered the cost of the main equipment, the purchase price of the nutshells, basic services, and operation. A sensitivity analysis was developed, considering the price of the finished product and the volume of raw material processing varied up to ±25%. Furthermore, the total annual cost of the product was determined based on the production of 2100 tons/year of activated carbon. Two cash flows were developed and projected to periods of 10 years and 15 years of production, using a tax rate of 27%, a low discount rate (LDR) of 10% per year, and without external financing. For a 10-year production project, the net present value (NPV) was USD 2,785,624, the internal return rate (IRR) 21%, the return on investment (ROI) 25%, and the disc... [more]
A Small RO and MCDI Coupled Seawater Desalination Plant and Its Performance Simulation Analysis and Optimization
Shouguang Yao, Mengting Ji
December 17, 2020 (v1)
Keywords: coupled seawater desalination, membrane capacitive deionization, reverse osmosis, simulation analysis and optimization
To solve the problems of high specific energy consumption and excessive harmful ions in the water production of a small reverse osmosis (RO) plant, a desalination system coupling RO and membrane capacitive deionization (MCDI) is proposed in this study. Aiming at producing two cubic meters per day of fresh water with a salt concentration of less than 280 mg L−1, parameter matching optimization was carried out on two desalination system schemes of one-stage two-section RO and one-stage three-section RO coupled with MCDI. The results were compared with the parameter matching optimization results of the one-stage one-section RO and the one-stage two-section pure RO desalination system. The results show that compared with the pure RO desalination mode, the seawater desalination mode coupled with RO and MCDI reduces the specific energy consumption under the same effluent salt concentration. Moreover, it decreases the feed water pressure in front of the RO membrane, which can reduce the stand... [more]
The Changes of Flavonoids in Honey during Storage
Goran Šarić, Nada Vahčić, Danijela Bursać Kovačević, Predrag Putnik
December 17, 2020 (v1)
Keywords: flavonoids, floral origin, honey, HPLC, marker, storage
The purpose of this study was to determine the changes in the contents of flavonoids that were the most prevalent in acacia and multifloral honey during one year of storage. Samples were stored in transparent glass containers, at room temperature, on open shelves exposed to light during daytime. Eight individual flavonoids identified and quantified using HPLC-Diode Array Detector (DAD) belongs to three subgroups: flavonols (quercetin, luteolin, kaempferol and galangin), total flavanons (hesperetin and pinocembrin) and total flavones (apigenin and chrysin). Obtained results revealed that multifloral honey had more total flavonoids than acacia samples did. On average from all of the samples, multifloral honey had more of quercetin, hesperetin, luteolin, kaempferol and apigenin than acacia honey did. Content of flavonoids increased in samples between the 1st and 6th month of storage and then started to decrease until the 9th month, when they remained relatively constant all the way until... [more]
Plant Extracts as Green Corrosion Inhibitors for Different Metal Surfaces and Corrosive Media: A Review
Alan Miralrio, Araceli Espinoza Vázquez
December 17, 2020 (v1)
Keywords: aluminum, copper, green corrosion inhibition, plant extracts, Steel
Natural extracts have been widely used to protect metal materials from corrosion. The efficiency of these extracts as corrosion inhibitors is commonly evaluated through electrochemical tests, which include techniques such as potentiodynamic polarization, electrochemical impedance spectroscopy, and weight loss measurement. The inhibition efficiency of different extract concentrations is a valuable indicator to obtain a clear outlook to choose an extract for a particular purpose. A complementary vision of the effectiveness of green extracts to inhibit the corrosion of metals is obtained by means of surface characterizations; atomic force microscopy, scanning electron microscopy, and X-ray photoelectron spectroscopy analysis are experimental techniques widely used for this purpose. Moreover, theoretical studies are usually addressed to elucidate the nature of the corrosion inhibitor—metal surface interactions. In addition, calculations have been employed to predict how other organic subst... [more]
Upgrading of Biogas to Methane Based on Adsorption
Jun Liu, Qiang Chen, Peng Qi
December 17, 2020 (v1)
Subject: Materials
Keywords: 13X zeolite, Adsorption, biogas, carbon molecular sieve, methane
Upgrading raw biogas to methane (CH4) is a vital prerequisite for the utilization of biogas as a vehicle fuel or the similar field as well. In this work, biogas yield from the anaerobic fermentation of food waste containing methane (CH4, 60.4%), carbon dioxide (CO2, 29.1%), hydrogen sulfide (H2S, 1.5%), nitrogen (N2, 7.35%) and oxygen (O2, 1.6%) was upgraded by dynamic adsorption. The hydrogen sulfide was removed from the biogas in advance by iron oxide (Fe2O3) because of its corrosion of the equipment. Commercial 13X zeolite and carbon molecular sieve (CMS) were used to remove the other impurity gases from wet or dry biogas. It was found that neither 13X zeolite nor CMS could effectively remove each of the impurities in the wet biogas for the effect of water vapor. However, 13X zeolite could effectively remove CO2 after the biogas was dried with silica and showed a CO2 adsorption capacity of 78 mg/g at the condition of 0.2 MPa and 25 °C. Additionally, 13X zeolite almost did not adsorb... [more]
Experimental Investigation of Primary De-NOx Methods Application Effects on NOx and CO Emissions from a Small-Scale Furnace
Ladislav Lukáč, Miroslav Rimár, Miroslav Variny, Ján Kizek, Peter Lukáč, Gustáv Jablonský, Ján Janošovský, Marcel Fedák
December 17, 2020 (v1)
Keywords: combustion, flue-gas recirculation, furnace, nitrogen oxides, reburning
Nitrogen oxides (NOx) from combustion contribute significantly to atmospheric pollution. An experimental setup was employed to investigate the application of three primary denitrification methods, i.e., reburning (staged combustion), overfiring air (OFA), and flue-gas recirculation (FGR), individually and in combination, combusting natural gas (NG) and propane−butane gas (PBG). Fuel heat inputs of 16 and 18 kW and air excess coefficients of 1.1 and 1.2, respectively, were tested. The highest individual denitrification efficiency of up to 74% was obtained for FGR, followed by reburning and OFA. A denitrification efficiency between 8.9% (reburning + OFA) and 72% (reburning + OFA + FGR) with NG combustion was observed. Using a 20% FGR rate yielded denitrification efficiency of 74% for NG and 65% for PBG and also led to a significant decrease in carbon monoxide (CO) emissions, so this can be recommended as the most efficient denitrification and de-CO method in small-scale furnaces. Reburni... [more]
Enhanced Performance of Microbial Fuel Cells with Anodes from Ethylenediamine and Phenylenediamine Modified Graphite Felt
Egidijus Griškonis, Arminas Ilginis, Ilona Jonuškienė, Laurencas Raslavičius, Rolandas Jonynas, Kristina Kantminienė
December 17, 2020 (v1)
Subject: Biosystems
Keywords: anode modification, diamines, graphite felt, microbial fuel cell, Shewanella putrefaciens, surface power density
A microbial fuel cell (MFC) is a promising renewable energy option, which enables the effective and sustainable harvesting of electrical power due to bacterial activity and, at the same time, can also treat wastewater and utilise organic wastes or renewable biomass. However, the practical implementation of MFCs is limited and, therefore, it is important to improve their performance before they can be scaled up. The surface modification of anode material is one way to improve MFC performance by enhancing bacterial cell adhesion, cell viability and extracellular electron transfer. The modification of graphite felt (GF), used as an anode in MFCs, by electrochemical oxidation followed by the treatment with ethylenediamine or p-phenylenediamine in one-step short duration reactions with the aim of introducing amino groups on the surface of GF led to the enhancement of the overall performance characteristics of MFCs. The MFC with the anode from GF modified with p-phenylenediamine provided app... [more]
Supercritical Antisolvent Process for Pharmaceutical Applications: A Review
Paola Franco, Iolanda De Marco
December 17, 2020 (v1)
Keywords: biomedical field, coprecipitation, drug delivery, micronization, supercritical antisolvent
The supercritical antisolvent (SAS) technique has been widely employed in the biomedical field, including drug delivery, to obtain drug particles or polymer-based systems of nanometric or micrometric size. The primary purpose of producing SAS particles is to improve the treatment of different pathologies and to better the patient’s compliance. In this context, many active compounds have been micronized to enhance their dissolution rate and bioavailability. Aiming for more effective treatments with reduced side effects caused by drug overdose, the SAS polymer/active principle coprecipitation has mainly been proposed to offer an adequate drug release for specific therapy. The demand for new formulations with reduced side effects on the patient’s health is still growing; in this context, the SAS technique is a promising tool to solve existing issues in the biomedical field. This updated review on the use of the SAS process for clinical applications provides useful information about the ac... [more]
The Significance of Natural Product Derivatives and Traditional Medicine for COVID-19
Dongdong Wang, Jiansheng Huang, Andy Wai Kan Yeung, Nikolay T. Tzvetkov, Jarosław O. Horbańczuk, Harald Willschke, Zhibo Gai, Atanas G. Atanasov
December 17, 2020 (v1)
Subject: Biosystems
Keywords: coronavirus, COVID-19, natural products, SARS-CoV, traditional Chinese medicine
Coronavirus disease 2019 (COVID-19) is caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). To date, there have been more than 10 million reported cases, more than 517,000 deaths in 215 countries, areas or territories. There is no effective antiviral medicine to prevent or treat COVID-19. Natural products and traditional medicine products with known safety profiles are a promising source for the discovery of new drug leads. There is increasing number of publications reporting the effect of natural products and traditional medicine products on COVID-19. In our review, we provide an overview of natural products and their derivatives or mimics, as well as traditional medicine products, which were reported to exhibit potential to inhibit SARS-CoV-2 infection in vitro, and to manage COVID-19 in vivo, or in clinical reports or trials. These natural products and traditional medicine products are categorized in several classes: (1) anti-malaria drugs including chloroquine an... [more]
The Importance of Dose Intensity When Administering Cytotoxic Chemotherapy in NSCLC—A Matter as Actual Now as in the Past
Cornelia Nitipir, Cristina Orlov-Slavu, Mihaela Olaru, Andreea Parosanu, Ana-Maria Popa, Cristian Iaciu, Bogdan Catalin Popescu, Maria Alexandra Barbu, Cristina Pirlog, Valentin Calu, Andreea Catarina Popescu, Dragos Bumbacea, Cristian Paleru, Iulian Slavu, Lucian Alecu
December 17, 2020 (v1)
Subject: Biosystems
Keywords: administration, chemotherapy, dose intensity
Lung cancer, as the leading cause of death in oncology is one of the most challenging diseases nowadays. Even after the implementation of checkpoint inhibitors and targeted therapy as a standard of therapy for metastatic disease, the chemotherapy backbone remains essential in the treatment of these patients. This study aimed to evaluate how administration particularities in chemotherapy and toxicity management can influence the outcome. We conducted a retrospective single-institution study, at Elias University Emergency Hospital, Bucharest, Romania, between 2014 and 2018, in a heterogeneous patient population with metastatic non-small cell lung cancer that received combination chemotherapy. The inclusion criteria for this trial were—histological proof of non-small cell lung cancer (NSCLC), stage IV disease, ECOG (Eastern Cooperative Oncology Group) performance status of a maximum of two, treatment with cytotoxic chemotherapy for at least four courses (patients with fewer courses were e... [more]
Continuous Improvement Process in the Development of a Low-Cost Rotational Rheometer
Francisco J. Hernández-Rangel, María Z. Saavedra-Leos, Josefa Morales-Morales, Horacio Bautista-Santos, Vladimir A. Reyes-Herrera, José M. Rodríguez-Lelis, Pedro Cruz-Alcantar
December 17, 2020 (v1)
Keywords: design, quality function deployment, rheometer
The rheological characterization of fluids using a rheometer is an essential task in food processing, materials, healthcare or even industrial engineering; in some cases, the high cost of a rheometer and the issues related to the possibility of developing both electrorheological and magnetorheological tests in the same instrument have to be overcome. With that in mind, this study designed and constructed a low-cost rotational rheometer with the capacity to adapt to electro- and magneto-rheological tests. The design team used the method of continuous improvement through Quality Function Deployment (QFD) and risk analysis tools such as Failure Mode and Effect Analysis (FMEA) and Finite Element Analysis (FEA). These analyses were prepared in order to meet the customer’s needs and engineering requirements. In addition to the above, a manufacturing control based on process sheets was used, leading to the construction of a functional rheometer with a cost of USD $1500.
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