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Records Added in August 2019
Records added in August 2019
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Showing records 26 to 50 of 77. [First] Page: 1 2 3 4 Last
Evaluation of the Methane Production Potential of Catfish Processing Wastewater Using Various Anaerobic Digestion Strategies
Mark E. Zappi, Dhan Lord Fortela, Wayne Sharp, Rakesh Bajpai, Daniel Gang, William Holmes, Rafael Hernandez, Emmanuel D. Revellame
August 14, 2019 (v1)
Subject: Biosystems
Keywords: biogas, HCl pretreatment, NaOH pretreatment, nutrient amendment, ozonation
The U.S. catfish industry is a major industry that has been declining over the years due to imports competition and growing operational costs. Catfish processing wastewater management and high energy requirement put a large financial burden on catfish processing facilities. Recovered protein-based solids have provided some value-added co-products, however, more co-products are needed to offset processing costs. Anaerobic digestion is a proven waste treatment method that produces methane, which is an energetic co-product that can be used within the processing facilities. This study was conducted to evaluate the potential of anaerobic digestion as an alternative to the currently used aerobic biotreatment of catfish processing wastewater. Initial assessments indicated the recalcitrance of the full-strength wastewater to anaerobic digestion, yielding only ~4 m3 per ton (U.S.) of input chemical oxygen demand (CODinput). Thus, several strategies were evaluated to improve the methane yield fr... [more]
Degradation Kinetics of Anthocyanins in Sour Cherry Cloudy Juices at Different Storage Temperature
Aneta Wojdyło, Paulina Nowicka, Mirosława Teleszko
August 8, 2019 (v1)
Subject: Biosystems
Keywords: anthocyanins, cloudy juices, color, half-life periods, LC-PDA-ESI-MS QTof, Prunus cerasus L., stability
The aim of this study was to characterize in detail 25 sour cherry cultivars and provide data on their industrial processing into high-quality sour cherry cloudy juices (ScCJ). Anthocyanin composition was identified and quantified by LC-PDA-ESI-MS QTof, UPLC-PDA. Kinetic degradation (k × 103, t1/2, D value) and color (CIE La*b*) were measured before and after 190 days of storage at 4 °C and 30 °C. A total of five anthocyanins, four cyanidins (-3-O-sophoroside, -3-O-glucosyl-rutinoside, -3-O-glucoside, and -3-O-rutinoside) and one peonidin-3-O-rutinoside were detected across all investigated juices. Total anthocyanin content ranged from ~590 to ~1160 mg/L of juice, with the highest levels in Skierka, Nagy Erdigymulscu, Wilena, Wiblek, and Safir cvs., and the lowest in Dradem and Nanaones. During 190 days of storage a significant change was observed in the content of anthocyanins. Their degradation depended rather on the storage conditions (time and temperature) than on the type of antho... [more]
Control of Solvent-Based Post-Combustion Carbon Capture Process with Optimal Operation Conditions
Yih-Hang Chen, Ming-Tien Shen, Hsuan Chang, Chii-Dong Ho
August 8, 2019 (v1)
Keywords: Aspen Custom Modeler®, post-combustion, process control, rate-based model, solvent-based carbon capture
Solvent-based post-combustion carbon capture (PCC) is a mature and essential technology to solve the global warming problem. The high energy consuming issue and the flexible operation required by the power plants inquire about the development of effective control systems for PCC plants. This study proposes the optimal-based control approach that utilizes optimal set-point values for the quality controllers. The five optimal-based control schemes studied all employed L/G (liquid to gas ratio in absorber) as one quality control variable. Performance comparisons with a typical conventional control scheme are conducted employing a rate-based dynamic model for the MEA (monoethanolamine) solvent PCC process developed on a commercial process simulator. Compared to the typical control scheme, the optimal-based control schemes provide faster responses to the disturbance changes from the flue gas conditions and the set-point change of the CO2 capture efficiency, as well as better results in term... [more]
Development and Permeability Testing of Self-Emulsifying Atorvastatin Calcium Pellets and Tablets of Compressed Pellets
Mine Diril, Yesim Karasulu, Miltiadis Toskas, Ioannis Nikolakakis
August 8, 2019 (v1)
Subject: Materials
Keywords: atorvastatin calcium, cytotoxicity, drug release, permeability, self-emulsifying pellets, self-emulsifying tablets
Self-emulsifying pellets (SEPs) of Atorvastatin Calcium (AtrCa) were developed and processed into tablets (SETs). Self-emulsifying drug delivery system (SEDDS) composed of oleic acid, Tween 20, Span 80 and N-Methyl-2-pyrolidone gave great solubility improvement and was used as oil in water emulsion for the preparation of SEPs. Due to the high 60% w/w SEDDS content required to achieve a therapeutic dose in the final tablet form, sonication was necessary to improve fluidity and stability. Colloidal silicon dioxide (CSD) and microcrystalline cellulose (MCC) were the solids in the pellet formulation employed at a ratio 7:3, which enabled production of pellets with high SEDDS content and acceptable friability as well. Emulsions were characterized physico-chemically, SEPs for physical properties and reconstitution, and tablets of compressed pellets for mechanical strength, disintegration into pellets and drug release. SEPs compressed with 30% MCC at 60 MPa gave tablets of adequate strength t... [more]
Optimization of Post Combustion CO2 Capture from a Combined-Cycle Gas Turbine Power Plant via Taguchi Design of Experiment
Ben Alexanda Petrovic, Salman Masoudi Soltani
August 8, 2019 (v1)
Keywords: Aspen Plus, Carbon Dioxide Capture, CCGT, Minitab, Optimization, Taguchi
The potential of carbon capture and storage to provide a low carbon fossil-fueled power generation sector that complements the continuously growing renewable sector is becoming ever more apparent. An optimization of a post combustion capture unit employing the solvent monoethanolamine (MEA) was carried out using a Taguchi design of experiment to mitigate the parasitic energy demands of the system. An equilibrium-based approach was employed in Aspen Plus to simulate 90% capture of the CO2 emitted from a 600 MW natural gas combined-cycle gas turbine power plant. The effects of varying the inlet flue gas temperature, absorber column operating pressure, amount of exhaust gas recycle, and amine concentration were evaluated using signal to noise ratios and analysis of variance. The optimum levels that minimized the specific energy requirements were a: flue gas temperature = 50 °C; absorber pressure = 1 bar; exhaust gas recirculation = 20% and; amine concentration = 35 wt%, with a relative im... [more]
Yield, Phytochemical Constituents, and Antibacterial Activity of Essential Oils from the Leaves/Twigs, Branches, Branch Wood, and Branch Bark of Sour Orange (Citrus aurantium L.)
Mohammad K. Okla, Saud A. Alamri, Mohamed Z.M. Salem, Hayssam M. Ali, Said I. Behiry, Ramadan A. Nasser, Ibrahim A. Alaraidh, Salem M. Al-Ghtani, Walid Soufan
August 8, 2019 (v1)
Subject: Biosystems
Keywords: antibacterial activity, Citrus aurantium, clevenger, essential oils, GC–MS, hydrodistillation, phytochemical
In the present work, essential oils (EOs) extracted from different parts of sour orange Citrus aurantium (green leaves/twigs, small branches, wooden branches, and branch bark) were studied through gas chromatography coupled with mass spectrometry (GC/MS). Furthermore, the EOs in the amounts of 5, 10, 15, 20, and 25 µL were studied for their antibacterial activity against three pathogenic bacteria, Agrobacterium tumefaciens, Dickeya solani, and Erwinia amylovora. The main EO compounds in the leaves/twigs were 4-terpineol (22.59%), D-limonene (16.67%), 4-carvomenthenol (12.84%), and linalool (7.82%). In small green branches, they were D-limonene (71.57%), dodecane (4.80%), oleic acid (2.72%), and trans-palmitoleic acid (2.62%), while in branch bark were D-limonene (54.61%), γ-terpinene (6.68%), dodecane (5.73%), and dimethyl anthranilate (3.13%), and in branch wood were D-limonene (38.13%), dimethyl anthranilate (8.13%), (-)-β-fenchol (6.83%), and dodecane (5.31%). At 25 µL, the EO from... [more]
Global Evolution Commended by Localized Search for Unconstrained Single Objective Optimization
Rashida Adeeb Khanum, Muhammad Asif Jan, Nasser Tairan, Wali Khan Mashwani, Muhammad Sulaiman, Hidayat Ullah Khan, Habib Shah
August 8, 2019 (v1)
Subject: Optimization
Keywords: adaptive differential evolution, evolutionary computation, external archives, global search, hybridization, local search, metaheuristics, Optimization, population minimization
Differential Evolution (DE) is one of the prevailing search techniques in the present era to solve global optimization problems. However, it shows weakness in performing a localized search, since it is based on mutation strategies that take large steps while searching a local area. Thus, DE is not a good option for solving local optimization problems. On the other hand, there are traditional local search (LS) methods, such as Steepest Decent and Davidon−Fletcher−Powell (DFP) that are good at local searching, but poor in searching global regions. Hence, motivated by the short comings of existing search techniques, we propose a hybrid algorithm of a DE version, reflected adaptive differential evolution with two external archives (RJADE/TA) with DFP to benefit from both search techniques and to alleviate their search disadvantages. In the novel hybrid design, the initial population is explored by global optimizer, RJADE/TA, and then a few comparatively best solutions are shifted to the ar... [more]
Comparison of Multi-Objective Evolutionary Algorithms to Solve the Modular Cell Design Problem for Novel Biocatalysis
Sergio Garcia, Cong T. Trinh
August 8, 2019 (v1)
Subject: Optimization
Keywords: constraint-based modeling, metabolic engineering, metabolic network modeling, modular cell, modular design, modularity, MOEA, multi-objective evolutionary algorithms, multi-objective optimization
A large space of chemicals with broad industrial and consumer applications could be synthesized by engineered microbial biocatalysts. However, the current strain optimization process is prohibitively laborious and costly to produce one target chemical and often requires new engineering efforts to produce new molecules. To tackle this challenge, modular cell design based on a chassis strain that can be combined with different product synthesis pathway modules has recently been proposed. This approach seeks to minimize unexpected failure and avoid task repetition, leading to a more robust and faster strain engineering process. In our previous study, we mathematically formulated the modular cell design problem based on the multi-objective optimization framework. In this study, we evaluated a library of state-of-the-art multi-objective evolutionary algorithms (MOEAs) to identify the most effective method to solve the modular cell design problem. Using the best MOEA, we found better solutio... [more]
Effects of Dark Brown Sugar Replacing Sucrose and Calcium Carbonate, Chitosan, and Chitooligosaccharide Addition on Acrylamide and 5-Hydroxymethylfurfural Mitigation in Brown Sugar Cookies
Yung-Shin Shyu, Hsin-I Hsiao, Jui-Yu Fang, Wen-Chieh Sung
August 8, 2019 (v1)
Subject: Biosystems
Keywords: 5-hydroxymethylfurfural, acrylamide, brown sugar cookie, chitooligosaccharide, dark brown sugar
The objective of this study was to evaluate effects of dark brown sugar on acrylamide and 5-hydroxymethylfurfural (HMF) levels in brown sugar cookies. Dark brown sugar was used as a raw material instead of sucrose, and chitosan, chitooligosaccharides, or calcium carbonate were added to investigate their effect on acrylamide and HMF mitigation. The results demonstrated that the higher the content of acrylamide in the dark brown sugar, the higher the amount of acrylamide produced in baked brown sugar cookies. The addition of dark brown sugar significantly increased the diameter and decreased the thickness of cookies, which induced more acrylamide formation. Therefore, the sucrose control cookies were harder and thicker than dark brown sugar cookies. The addition of 1% chitosan, chitooligosaccharide, or calcium carbonate did not reduce the acrylamide formation of the brown sugar cookies. The content of acrylamide and HMF in the sucrose control group was lower than that in dark brown sugar... [more]
Purification of Amygdalin from the Concentrated Debitterizing-Water of Apricot Kernelsusing XDA-1 Resin
Qing-An Zhang, Dong-Dong Wu, Chen-Xi Wei
August 8, 2019 (v1)
Subject: Biosystems
Keywords: amygdalin, apricot kernels, debitterizing water, macroporous resins, macroporous resins, separation
In this study, six macroporous resins were screened on their adsorption and de-adsorption characteristics for the amygdalin in the debitterizing wastewater concentrate (DWC). The results indicate that the XDA-1 resin exerts good adsorption and de-adsorption capacities on the amygdalin. In order to further confirm its feasibility, the factors affecting the capacity of adsorption and de-adsorption, and its adsorption mechanisms were also investigated. The results suggest that the optimum purification conditions were as follows: loading concentration of samples with 78.05 mg/mL, flow rate of 2 mL/min, and de-adsorption with 80% ethanol solution. The recovery rate was 88.75% and the relative content achieved 61.58% after purification by XDA-1 resin. The Freundlich model can be used to describe the entirety of the exothermic and physical adsorption processes. In summary, the conclusion which can be made from this research is that the wastewater generated from the debitterizing of apricot ke... [more]
Molecular Recognition and Cell Surface Biochemical Response of Bacillus thuringiensis on Triphenyltin
Hongling Zhang, Jinshao Ye, Huaming Qin, Xujun Liang, Yan Long
August 8, 2019 (v1)
Subject: Biosystems
Keywords: biodegradation, biosorption, mechanical properties, molecular recognition, Triphenyltin
Triphenyltin (TPT) has severely polluted the environment, and it often coexists with metal ions, such as Cu2+. This paper describes the cell’s molecular recognition of TPT, the interaction between TPT recognition and Cu2+ biosorption, and their effect on cell permeability. We studied the recognition of TPT by Bacillus thuringiensis cells and the effect of TPT recognition on Cu2+ biosorption by using atomic force microscopy to observe changes in cell surface mechanical properties and cellular morphology and by using flow cytometry to determine the cell growth status and cell permeability. The results show that B. thuringiensis can quickly recognize different media. The adhesion force of cells in contact with Tween 80 was significantly reduced to levels that were much lower than that of cells in contact with PBS. Conversely, the cell surface adhesion force increased as TPT became more degraded. B. thuringiensis cells maintained their original morphology after 48 h of TPT treatment. The a... [more]
A Review on Energy Consumption, Energy Efficiency and Energy Saving of Metal Forming Processes from Different Hierarchies
Mengdi Gao, Kang He, Lei Li, Qingyang Wang, Conghu Liu
August 8, 2019 (v1)
Subject: Energy Policy
Keywords: energy consumption, Energy Efficiency, energy-saving, metal forming process, press
Energy efficiency improvement and environmental impact reduction are emerging issues in the manufacturing industry. Aside from cutting, metal forming is also an important process in manufacturing. Metal forming is energy intensive because of the low energy efficiency of the used metal forming press. Although many literature reviews focused on the energy reduction and energy efficiency of machine tools, a comprehensive literature review of metal forming processes remains lacking because of the great difference between cutting machines and forming equipment. In addition, methods for energy efficiency and energy-saving still need to be promoted in metal forming. In this review, a novel hierarchy of the metal forming system was presented to describe the relationship among the equipment, process, and manufacturing system, providing a guideline of methods for energy efficiency and saving in metal forming. Then, existing energy consumption modeling and estimation theories and methods were dis... [more]
Single-Cell Receptor Quantification of an In Vitro Coculture Angiogenesis Model Reveals VEGFR, NRP1, Tie2, and PDGFR Regulation and Endothelial Heterogeneity
Si Chen, P. I. Imoukhuede
August 8, 2019 (v1)
Subject: Biosystems
Keywords: angiogenesis, coculture, endothelial tube formation, fibroblast, NRP, PDGFR, qFlow cytometry, Tie2, tyrosine kinase receptor, VEGFR
Angiogenesis, the formation of new blood vessels from pre-existing ones, is essential for both normal development and numerous pathologies. Systems biology has offered a unique approach to study angiogenesis by profiling tyrosine kinase receptors (RTKs) that regulate angiogenic processes and computationally modeling RTK signaling pathways. Historically, this systems biology approach has been applied on ex vivo angiogenesis assays, however, these assays are difficult to quantify and limited in their potential of temporal analysis. In this study, we adopted a simple two-dimensional angiogenesis assay comprised of human umbilical vein endothelial cells (HUVECs) and human dermal fibroblasts (HDFs) and examined temporal dynamics of a panel of six RTKs and cell heterogeneity up to 17 days. We observed ~2700 VEGFR1 (vascular endothelial growth factor receptor 1) per cell on 24-h-old cocultured HDF plasma membranes, which do not express VEGFR when cultured alone. We observed 4000−8100 VEGFR2 p... [more]
Advantages of Utilizing Population Balance Modeling of Crystallization Processes for Particle Size Distribution Prediction of an Active Pharmaceutical Ingredient
Tamar Rosenbaum, Li Tan, Joshua Engstrom
August 8, 2019 (v1)
Subject: Biosystems
Keywords: active pharmaceutical ingredient, crystallization, particle size control, population balance modeling
Active pharmaceutical ingredient (API) particle size distribution is important for both downstream processing operations and in vivo performance. Crystallization process parameters and reactor configuration are important in controlling API particle size distribution (PSD). Given the large number of parameters and the scale-dependence of many parameters, it can be difficult to design a scalable crystallization process that delivers a target PSD. Population balance modeling is a useful tool for understanding crystallization kinetics, which are primarily scale-independent, predicting PSD, and studying the impact of process parameters on PSD. Although population balance modeling (PBM) does have certain limitations, such as scale dependency of secondary nucleation, and is currently limited in commercial software packages to one particle dimension, which has difficulty in predicting PSD for high aspect ratio morphologies, there is still much to be gained from applying PBM in API crystallizat... [more]
Numerical Study of Pressure Fluctuation and Unsteady Flow in a Centrifugal Pump
Ling Bai, Ling Zhou, Chen Han, Yong Zhu, Weidong Shi
August 8, 2019 (v1)
Keywords: centrifugal pump, numerical simulation, pressure fluctuation, unsteady flow
A pump is one of the most important machines in the processes and flow systems. The operation of multistage centrifugal pumps could generate pressure fluctuations and instabilities that may be detrimental to the performance and integrity of the pump. In this paper, a numerical study of the influence of pressure fluctuations and unsteady flow patterns was undertaken in the pump flow channel of three configurations with different diffuser vane numbers. It was found that the amplitude of pressure fluctuation in the diffuser was increased gradually with the increase in number of diffuser vanes. The lower number of diffuser vanes was beneficial to obtain a weaker pressure fluctuation intensity. With the static pressure gradually increasing, the effects of impeller blade passing frequency attenuated gradually, and the effect of diffuser vanes was increased gradually.
A Model for Optimizing Location Selection for Biomass Energy Power Plants
Chia-Nan Wang, Tsang-Ta Tsai, Ying-Fang Huang
August 8, 2019 (v1)
Keywords: biomass energy, FAHP, FMCDM, MCDM, Optimization, site selection, TOPSIS
In addition to its potential for wave power, wind power, hydropower, and solar power, it can be said that Vietnam is a country with great potential for biomass energy derived from agricultural waste, garbage, and urban wastewater, which are resources widely available across the country. This huge amount of biomass, however, if left untreated, could become a major source of pollution and cause serious impacts on ecosystems (soil, water, and air), as well as on human health. In this research, the authors present a fuzzy multicriteria decision-making model (FMCDM) for optimizing the site selection process for biomass power plants. All of the criteria affecting location selection are identified by experts and literature reviews; in addition, the fuzzy analytic hierarchy process (FAHP) method was utilized so as to identify the weight of all of the criteria in the second stage. Furthermore, the Technique for Order Preference by Similarity to an Ideal Solution (TOPSIS) is applied for ranking... [more]
Gaussian Process-Based Hybrid Model for Predicting Oxygen Consumption in the Converter Steelmaking Process
Sheng-Long Jiang, Xinyue Shen, Zhong Zheng
August 8, 2019 (v1)
Keywords: GPR, oxygen consumption, prediction model, steelmaking
Oxygen is one of the most important energies used in converter steelmaking processes of integrated iron and steel works. Precisely forecasting oxygen consumption before processing can benefit process control and energy optimization. This paper assumes there is a linear relationship between the oxygen consumption and input materials, and random noises are caused by other unmeasurable materials and unobserved reactions. Then, a novel hybrid prediction model integrating multiple linear regression (MLR) and Gaussian process regression (GPR) is introduced. In the hybrid model, the MLR method is developed to figure the global trend of the oxygen consumption, and the GPR method is applied to explore the local fluctuation caused by noise. Additionally, to accelerate the computational speed on the practical data set, a K-means clustering method is devised to respectively train a number of GPR models. The proposed hybrid model is validated with the actual data collected from an integrated iron a... [more]
Enhanced Anaerobic Performances of Kitchen Wastes in a Semi-Continuous Reactor by EDTA Improving the Water-Soluble Fraction of Fe
Yali Liu, Xiaorong Kang, Han Cheng
August 8, 2019 (v1)
Subject: Biosystems
Keywords: EDTA, Fe, kitchen wastes, methane, semi-continuous reactor
The addition of Fe2+ is considered an effective method for increasing methane production, but the added Fe2+ may not be absorbed by anaerobic microorganisms due to complex chemical reactions. In this study, ethylenediaminetetraacetic acid (EDTA) was used as a ligand of Fe2+ (EDTA-Fe) to promote the dissolution of Fe, and the anaerobic performances of kitchen wastes (KWs) in a semi-continuous reactor were studied. The results indicated that the biogas yields and methane contents were enhanced to 594−613 mL·g−1VSadd·d−1 and 63.6−64.4% at an organic loading rate (OLR) of 2.5 gVSadd·L−1·d−1 due to EDTA-Fe addition. Simultaneously, the EDTA-Fe was more effective than Fe2+ in preventing the acidification of KWs with a high OLR (5.0 gVSadd·L−1·d−1). In addition, the sequential extraction results showed that the water-soluble fraction of Fe in the R3 (EDTA-Fe addition) was 1.49-fold of that in the R2 with Fe2+ addition. The contents of coenzymes F420 and F430 were also improved 1.09 and 1.11 t... [more]
Advances in Energy Systems Engineering and Process Systems Engineering in China—A Review Starting from Sargent’s Pioneering Work
Wenhan Qian, Pei Liu, Zheng Li
August 8, 2019 (v1)
Keywords: energy systems engineering, nonlinear programming, Optimization, process design, process systems engineering
Process systems engineering (PSE), after being proposed by Sargent and contemporary researchers, has been fast developing in various domains and research communities around the world in the last couple of decades, with energy systems engineering featuring a typical yet still fast propagating domain, and the Chinese PSE community featuring a typical community with its own unique challenges for applying PSE theory and methods. In this paper, development of energy systems engineering and process systems engineering in China is discussed, and Sargent’s impacts on these two fields are the main focus. Pioneering work conducted by Sargent is firstly discussed. Then, a venation on how his work and thoughts have motivated later researchers and led to progressive advances is reviewed and analyzed. It shows that Sargent’s idea of optimum design and his work on nonlinear programming and superstructure modelling have resulted in well-known methods that are widely adopted in energy systems engineeri... [more]
Syngas Production from Combined Steam Gasification of Biochar and a Sorption-Enhanced Water−Gas Shift Reaction with the Utilization of CO2
Supanida Chimpae, Suwimol Wongsakulphasatch, Supawat Vivanpatarakij, Thongchai Glinrun, Fasai Wiwatwongwana, Weerakanya Maneeprakorn, Suttichai Assabumrungrat
August 8, 2019 (v1)
Keywords: gasification, multi-functional material, sorption-enhanced water–gas shift
This research aims at evaluating the performance of a combined system of biochar gasification and a sorption-enhanced water−gas shift reaction (SEWGS) for synthesis gas production. The effects of mangrove-derived biochar gasification temperature, pattern of combined gasification and SEWGS, amount of steam and CO2 added as gasifying agent, and SEWGS temperature were studied in this work. The performances of the combined process were examined in terms of biochar conversion, gaseous product composition, and CO2 emission. The results revealed that the hybrid SEWGS using one-body multi-functional material offered a greater amount of H2 with a similar amount of CO2 emissions when compared with separated sorbent/catalyst material. The gasification temperature of 900 °C provided the highest biochar conversion of ca. 98.7%. Synthesis gas production was found to depend upon the amount of water and CO2 added and SEWGS temperature. Higher amounts of H2 were observed when increasing the amount of w... [more]
Systems Evaluation through New Grey Relational Analysis Approach: An Application on Thermal Conductivity—Petrophysical Parameters’ Relationships
Saad Ahmed Javed, Aqib Mashood Khan, Wenjie Dong, Adil Raza, Sifeng Liu
August 8, 2019 (v1)
Subject: Other
Keywords: absolute GRA, grey relational analysis, petrophysical parameters, second synthetic GRA, thermal conductivity
The current study introduces a new technique for the analysis of uncertain systems and uncertain processes in geothermics/earth sciences. The method is the second synthetic grey relational analysis (SSGRA) model, which incorporated the advantages of both Deng’s GRA model and the bidirectional absolute GRA model. The SSGRA model has been earlier successfully applied in project management and healthcare systems. The current study is a pioneer in demonstrating the feasibility of the SSGRA model in a geothermal environment. In the current study, the model was used to determine the associations between thermal conductivity and petrophysical parameters in an Algerian reservoir. The results revealed that thermal conductivity is most strongly associated with porosity followed by density and permeability. Their relationships are also discussed. The study concludes with valuable insights about the model and its application in engineering and natural sciences especially when the system contains u... [more]
Manufacturing Process, In Vivo and In Vitro Digestibility Assessment of an Enteral Feeding Product Hydrolyzed from Locally Available Ingredients Using Commercial Enzymes
Nguyen Thi Quynh Hoa, Luu Ngan Tam, Luu Van Thien Phu, Than Van Thai, Duy Chinh Nguyen, Dong Thi Anh Dao
August 8, 2019 (v1)
Keywords: hydrolyzed protein, in vivo digestibility, pepsin digestibility, ready-to-use enteral feeding product, Swiss mice
A ready-for-use enteral feeding product was manufactured based on energy standard mixing using hydrolyzed products from local foods (i.e., loin pork, carrot, pumpkin, soybean, rice, and potato). When compared to enteral foods based on defined ingredients, the manufactured product is more cost-effective, appropriately functional and has similar physicochemical properties. Relative protein digestibility for in vitro value was tested by using enzyme pepsin, pH-drop and pH-stat method with three different enzymes. The product was shown to be easily digested with an in vivo digestibility value of 89.7%. Molecule sizes of components in the product ranged from 3.5 to 8.5 kDa, determined by SDS-PAGE, and the average molecular weight was 1.52 kDa, determined by Gel Permeation Chromatography (GPC) method. In terms of nutritional value, the product achieved a caloric density of 1 kcal/mL, dietary fibers of 1.48 g per 100 mL and provided both oligomeric and monomeric forms of protein. In addition,... [more]
Numerical Determination of RVE for Heterogeneous Geomaterials Based on Digital Image Processing Technology
Lanlan Yang, Weiya Xu, Qingxiang Meng, Wei-Chau Xie, Huanling Wang, Mengcheng Sun
August 8, 2019 (v1)
Subject: Other
Keywords: coefficient of variation, CV, digital image processing, DIP, heterogeneous geomaterials, mechanical properties, representative volume element, RVE
Representative volume element (RVE) is an important parameter in numerical tests of mechanical properties of heterogeneous geomaterials. For this study, a digital image processing (DIP) technology was proposed for estimating the RVE of heterogeneous geomaterials. A color image of soil and rock mixture (SRM) with size of 400 × 400 mm2 taken from a large landslide was used to illustrate the determination procedure of the SRM. Six sample sizes ranging from 40 × 40 mm2 to 240 × 240 mm2 were investigated, and twelve random samples were taken from the binarized image for each sample size. A connected-component labeling algorithm was introduced to identify the microstructure. After establishing the numerical finite difference models of the samples, a set of numerical triaxial tests under different confining pressures were carried out. Results show that the size of SRM sample affects the estimation of the mechanical properties, including compressive strength, cohesion, and internal friction an... [more]
Effect of Heating Oxidation on the Surface/Interface Properties and Floatability of Anthracite Coal
Guoqiang Rong, Mengdi Xu, Dongyue Wang, Xiahui Gui, Yaowen Xing
August 8, 2019 (v1)
Subject: Materials
Keywords: bubble-particle wrap angle, floatability, heating oxidation, induction time, surface/interface properties
Oxidation processes of coal surfaces are both fundamental and interesting from academic and engineering points of view. In this work, we comprehensively analyzed the mechanism of heating oxidation at 200 °C on the surface/interface characters and the floatability of anthracite coal. The variations of surface/interface characters were studied using SEM (scanning electron microscopy), FTIR (Fourier transform infrared spectroscopy), and XPS (X-ray photoelectron spectroscopy). The floatability was further identified using Induction Time and Bubble-Particle Wrap Angle. It was found that, after heating oxidation at 200 °C, both surface ravines and oxygen-containing groups were increased. The degradation of hydroxyl on anthracite could be neglected during the heating, while the oxidation of hydrocarbon chains dominated the balance of hydrophobicity and hydrophilicity on coal surface. The induction time significantly increased from 200 ms to 1200 ms and 2000 ms after 10 h and 20 h of heating o... [more]
Applied Research Towards Industry 4.0: Opportunities for SMEs
Ilaria Zambon, Gianluca Egidi, Fabiano Rinaldi, Sirio Cividino
August 8, 2019 (v1)
Subject: Energy Policy
Keywords: industrial processes, Industry 4.0, job safety, Renewable and Sustainable Energy, SMEs, sustainable development, technologies
Industry 4.0 designates the recent digital revolution in the industrial sector, evolving from the comprehensive networking and automation of all the productive areas. Equipment, machinery, materials and products permit to (i) distinguish dealing out environmental settings and current status via sensors; (ii) join them through fixed software; and (iii) progress production procedures in an exclusive method. Additionally, Industry 4.0 exposes new trials to enterprises, especially small and medium-sized enterprises (SMEs). Firms should advance approaches to (i) achieve chances of innovation and digitalization; (ii) expand their processes; and (iii) define innovative business models. Based on these premises, a well-organized political, legal and infrastructural outline is essential to build up a business having an Industry 4.0 approach. Though bigger firms can get ahead through innovation processes and predicting the potential digitalization risks for their business models, SMEs may be in t... [more]
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