Records with Subject: Other
Showing records 1 to 25 of 210. [First] Page: 1 2 3 4 5 Last
Effects of Low-Temperature Drying with Intermittent Gaseous Chlorine Dioxide Treatment on Texture and Shelf-Life of Rice Cakes
Timilehin Martins Oyinloye, Won Byong Yoon
May 22, 2020 (v1)
Subject: Other
Keywords: cutting analysis, image processing, intermittent ClO2 drying, microbial growth model
We investigated the effect of chlorine dioxide (ClO2) under low temperature drying to suppress rice cake stickiness during the cutting process by initiating the onset of retrogradation until the stickiness is minimized for shelf-life extension. The intermittent ClO2 application at low-temperature drying was conducted at 10 °C for different drying periods (0, 6, 12, 18, and 24 h). Texture analysis showed significant differences with increasing values of hardness (901.39 ± 53.87 to 12,653 ± 1689.35 g) and reduced values of modified adhesiveness (3614.37 ±578.23 to 534.81 ± 89.37 g). The evaluation of rice cake stickiness during the cutting process revealed an optimum drying period of 18 h with no significant difference (p ≤ 0.05) compared to the 24 h drying process. Microbial contamination during the drying process increased, with microbial load from 6.39 ± 0.37 to 7.94 ± 0.29 CFU/g. Intermittent ClO2 application at 22 ppm successfully reduced the microbial load by 63% during drying proc... [more]
Ketone Solvent to Reduce the Minimum Miscibility Pressure for CO2 Flooding at the South Sumatra Basin, Indonesia
Adi Novriansyah, Wisup Bae, Changhyup Park, Asep K. Permadi, Shabrina Sri Riswati
May 22, 2020 (v1)
Subject: Other
Keywords: alcohol, CO2 flooding, ketone, minimum miscibility pressure, vanishing interfacial tension
This paper experimentally analyzes the chemical additives, i.e., methanol and ethanol, as alcohol solvents, and acetone as a ketone solvent, and the temperature influencing the minimum miscibility pressure (MMP) that is essential to design miscible CO2 flooding at an oil field, the South Sumatra basin, Indonesia. The experiments were designed to measure CO2-oil interfacial tension with the vanishing interfacial tension (VIT) method in the ranges up to 3000 psi (208.6 bar) and 300 degrees Celsius. The experiment results show that lower temperatures, larger solvent volumes, and the acetone were effective in reducing MMP. The acetone, an aprotic ketone solvent, reduced MMP more than the methanol and the ethanol in the CO2-oil system. The high temperature was negative to obtain the high CO2 solubility into the oil as well as the lower MMP. The experimental results confirm that the aprotic ketone solvent could be effective in decreasing the MMP for the design of miscible CO2 flooding at the... [more]
Influence of Fluid Properties on Intensity of Hydrodynamic Cavitation and Deactivation of Salmonella typhimurium
Moein Talebian Gevari, Ayhan Parlar, Milad Torabfam, Ali Koşar, Meral Yüce, Morteza Ghorbani
May 22, 2020 (v1)
Subject: Other
Keywords: bacteria deactivation, hydrodynamic cavitation, microfluidics, Salmonella typhimurium, water treatment
In this study, three microfluidic devices with different geometries are fabricated on silicon and are bonded to glass to withstand high-pressure fluid flows in order to observe bacteria deactivation effects of micro cavitating flows. The general geometry of the devices was a micro orifice with macroscopic wall roughness elements. The width of the microchannel and geometry of the roughness elements were varied in the devices. First, the thermophysical property effect (with deionized water and phosphate-buffered saline (PBS)) on flow behavior was revealed. The results showed a better performance of the device in terms of cavitation generation and intensity with PBS due to its higher density, higher saturation vapor pressure, and lower surface tension in comparison with water. Moreover, the second and third microfluidic devices were tested with water and Salmonella typhimurium bacteria suspension in PBS. Accordingly, the presence of the bacteria intensified cavitating flows. As a result,... [more]
Study on the Stability of Produced Water from Alkali/Surfactant/Polymer Flooding under the Synergetic Effect of Quartz Sand Particles and Oil Displacement Agents
Bin Huang, Chen Wang, Weisen Zhang, Cheng Fu, Haibo Liu, Hongwei Wang
May 18, 2020 (v1)
Subject: Other
Keywords: ASP oil displacement agent, oil droplet stability, oil–water interface, produced water system, quartz sand particle
With the wide application of ASP (alkali/surfactant/polymer) flooding oil recovery technology, the produced water from ASP flooding has increased greatly. The clay particles carried by crude oil in the process of flow have a synergetic effect with oil displacement agents in the produced water, which increases the treatment difficulty of produced water. The stability of produced water is decided by the stability of oil droplets in the ASP-flooding-produced water system. The oil content, Zeta potential, interfacial tension and oil droplet size are important parameters to characterize the stability of produced water. In this paper, the changes of the oil content, Zeta potential, interfacial tension and oil droplet size of ASP flooding oily wastewater under the synergetic effect of different concentrations of quartz sand particles and oil displacement agents were studied by laboratory experiments. The experimental results show that the negatively charged quartz sand particles can absorb ac... [more]
Experimental Study on the Effect of ASP Flooding on Improving Oil Recovery in Low Permeability Reservoirs Based on a Partial Quality Tool
Bin Huang, Xinyu Hu, Cheng Fu, Quan Zhou
May 18, 2020 (v1)
Subject: Other
Keywords: ASP flooding, low permeability oil layer, maximum injection pressure, oil recovery, partial quality tool
In order to solve the problem of the poor oil displacement effect of high molecular weight alkali/surfactant/polymer (ASP) solution in low permeability reservoirs, Daqing Oilfield uses a partial quality tool to improve the oil displacement effect in low permeability reservoirs. In the formation, the partial quality tool degrades the polymer through active shearing action, reducing the molecular weight of the polymer, to improve the matching degree to the low permeability oil layer and the oil recovery. In order to study the ability of the partial quality tool to improve the oil displacement effect, the matching degree of high molecular weight ASP solution to low permeability cores is studied, and the ability of quality control tools to change the molecular weight is studied. Then, experimental research on the pressure and oil displacement effect of high molecular weight ASP solution before and after the actions of the partial quality tool is carried out. The results show that ASP solut... [more]
Experimental Study and Application of Rheological Properties of Coal Gangue-Fly Ash Backfill Slurry
Yumin Wang, Yucheng Huang, Yuxin Hao
May 8, 2020 (v1)
Subject: Other
Keywords: backfill mining, fly ash, gangue, rheological properties
From the perspective of resource recovery and environmental protection, coal gangue-fly ash cemented backfill coal mining has become an important direction for the green development of coal mines in recent years. Analysis of the rheological parameters of backfill slurry is the basic principle to design a backfill pipeline system. Coal gangue-fly ash backfill slurry has a mass concentration of 76% to 79% and a maximum particle size 20 mm. Therefore, it is difficult to use conventional rheometers for experimental analyses of the rheological parameters of such fluids. We developed a rheometer for high-concentration coal gangue backfill slurry (HCGS rheometer) based on the coal gangue-fly ash backfill practice of Gonggeying Mine, and analyzed the rheological properties of the backfill slurry. The experimental results showed that the Reynolds number of the coal gangue-fly ash backfill slurry was much smaller than the critical Reynolds number, indicating the flow state in the pipeline was la... [more]
Effects of Wall Ventilation on the Shock-wave/Viscous-Layer Interactions in a Mach 2.2 Intake
Humrutha Gunasekaran, Thillaikumar Thangaraj, Tamal Jana, Mrinal Kaushik
April 14, 2020 (v1)
Subject: Other
Keywords: boundary layer, cavity, porosity, Schlieren flow visualization technique, shock wave, static pressure, wall ventilation
In order to achieve proficient combustion with the present technologies, the flow through an aircraft intake operating at supersonic and hypersonic Mach numbers must be decelerated to a low-subsonic level before entering the combustion chamber. High-speed intakes are generally designed to act as a flow compressor even in the absence of mechanical compressors. The reduction in flow velocity is essentially achieved by generating a series of oblique as well as normal shock waves in the external ramp region and also in the internal isolator region of the intake. Thus, these intakes are also referred to as mixed-compression intakes. Nevertheless, the benefits of shock-generated compression do not arise independently but with enormous losses because of the shockwave and boundary layer interactions (SBLIs). These interactions should be manipulated to minimize or alleviate the losses. In the present investigation a wall ventilation using a new cavity configuration (having a cross-section simil... [more]
Correction: Koşucu, M.M., et al. Hydrodynamic and Hydrographic Modeling of Istanbul Strait. Processes 2019, 7, 710
Mehmet Melih Koşucu, Mehmet Cüneyd Demirel, V.S. Ozgur Kirca, Mehmet Özger
April 14, 2020 (v1)
Subject: Other
We were not aware of an error made in the proofreading phase; therefore, we wish to make the following correction to Figure 1b from this paper [...]
The Demulsification Properties of Cationic Hyperbranched Polyamidoamines for Polymer Flooding Emulsions and Microemulsions
Yangang Bi, Zhi Tan, Liang Wang, Wusong Li, Congcong Liu, Zhantao Wang, Xiangchen Liu, Xinru Jia
April 1, 2020 (v1)
Subject: Other
Keywords: cationic hyperbranched polymers, demulsifiers, interfacial tension, microemulsion, polymer-flooding emulsion, turbidity
Polymer flooding emulsions and microemulsions caused by tertiary oil recovery technologies are harmful to the environment due to their excellent stability. Two cationic hyperbranched polyamidoamines (H-PAMAM), named as H-PAMAM-HA and H-PAMAM-ETA, were obtained by changing the terminal denotation agents to H-PAMAM, which was characterized by 1H NMR, FT-IR, and amine possession, thereby confirmed the modification. Samples (300 mg/L) were added to the polymer flooding emulsion (1500 mg/L oil concentration) at 30 °C for 30 min and the H-PAMAM-HA and H-PAMAM-ETA were shown to perform at 88% and 91% deoil efficiency. Additionally, the increased settling time and the raised temperature enhanced performance. For example, an oil removal ratio of 97.7% was observed after dealing with the emulsion for 30 min at 60 °C, while 98.5% deoil efficiency was obtained after 90 min at 45 °C for the 300 mg/L H-PAMAM-ETA. To determine the differences when dealing with the emulsion, the interfacial tension, ζ... [more]
Evaluation of Thermal Effects on the Bioactivity of Curcumin Microencapsulated with Porous Starch-Based Wall Material Using Spray Drying
Chenwei Huang, Shengwen Wang, Huaiwen Yang
April 1, 2020 (v1)
Subject: Other
Keywords: color attribute, encapsulated curcumin, free radical scavenging activity, oven heating, spray drying
Curcumin was microencapsulated by porous starch using a spray dryer with a particle size between 1.5 and 2.0 µm and subjected to water bath (40−100 °C) and oven heating (150−200 °C) in comparison to non-encapsulated samples. The minimum possible encapsulation rate ranged from 26.75 to 52.23%. A reasonable thermal stability was observed after water bath heating with regard to 2,2-diphenyl-1-picrylhydrazyl free radical (DPPH) scavenging activity. On the other hand, the increase in oven heating temperature caused significant alterations compared with the control samples (p < 0.05). The encapsulated particles subjected to oven heating at 170 °C demonstrated serious collapse. The DPPH scavenging activity of non-encapsulated curcumin was significantly reduced (p < 0.05) from 48.94% ± 3.72% (control, 0 °C) to 40.42% ± 2.23% (oven heating, 160 °C); however, remained stable for the encapsulated samples (51.18% ± 4.86%−50.02% ± 1.79%) without significant difference (p < 0.05). The ABTS... [more]
Methane Emission Reduction Enhanced by Hydrophobic Biochar-Modified Soil Cover
Beibei Wu, Beidou Xi, Xiaosong He, Xiaojie Sun, Qian Li, Quanyi Ouche, Hongxia Zhang, Chennan Xue
March 25, 2020 (v1)
Subject: Other
Keywords: biocover, hydrophobic biochar, landfill cover, methane
The microbial oxidation of CH4 in biochar-modified soil cover is considered a potent option for the mitigation of emissions from old landfills or sites containing wastes full of low CH4 generation rates. The mechanism of methane oxidizing bacteria (MOB) can be enhanced by amending the landfill cover soil with biochar, which is recalcitrant to biological degradation and can adsorb CH4 while facilitating the growth and activity of MOB within its porous structure. However, the increase in the permeability coefficient and water content of the cover due to the addition of biochar also affects the methane removal efficiency. A hydrophobic biochar modified by KH-570 was employed to reduce the water content and to promote the diffusion and oxidation of CH4 in the cover. Several series of small-scale column tests were conducted to quantify the CH4 oxidation properties of the landfill cover soil amended with biochar and hydrophobic biochar under different levels of exposed CH4 concentrations (5%... [more]
Comprehensive Environmental Impact Assessment of a Combined Petroleum Coke and Natural Gas to Fischer-Tropsch Diesel Process
Thomas A. Adams II
March 13, 2020 (v1)
Subject: Other
In this study, a well-to-wheels life cycle assessment was conducted to determine the environmental impacts from disposing of petroleum coke by converting it into liquid fuel. Specifically, three processes for converting petroleum coke and natural gas to Fischer Tropsch diesel were investigated, both with and without carbon capture and sequestration (CCS). Impact categories were calculated using the EPA’s TRACI 2.1 US-Canada 2008 midpoint method in SimaPro software. In addition, the impact of grid emissions on the overall process was assessed using two representative Canadian locations with high (Alberta) and low (Ontario) grid emissions. The results of each impact category were compared among the designs and against conventional petroleum and oil-sands derived diesel. Key findings showed that the proposed designs when operated using CCS in the low-emissions-grid location had lower life cycle GHG emissions than conventional petroleum and oil-sands derived diesel. Nevertheless, the vario... [more]
Acknowledgement to Reviewers of Processes in 2019
Processes Editorial Office
March 12, 2020 (v1)
Subject: Other
The editorial team greatly appreciates the reviewers who have dedicated their considerable timeand expertise to the journal’s rigorous editorial process over the past 12 months, regardless ofwhether the papers are finally published or not [...]
Comparison of Steel Manufacturing Off-Gas Utilization Methods via Life Cycle Analysis
Lingyan Deng, Thomas Adams
March 4, 2020 (v1)
Subject: Other
Keywords: Blast furnace gas, Coke oven gas, Combined cycle power plant, Life Cycle Analysis, Methanol production, SimaPro
This is a submission of source file of the life cycle analysis of steel manufacturing off-gas utilization systems using SimaPro V9. It includes five locations: Ontario, the USA, Finland, Mexico, and China.
Solid-State Anaerobic Digestion of Dairy Manure from a Sawdust-Bedded Pack Barn: Moisture Responses
Eunjong Kim, Seunghun Lee, Hyeonsoo Jo, Jihyeon Jeong, Walter Mulbry, Shafiqur Rhaman, Heekwon Ahn
February 24, 2020 (v1)
Subject: Other
Keywords: biogas, dairy manure, methane, moisture content, solid-state anaerobic digestion
Bedded pack manure has long been considered an unsuitable feedstock for conventional anaerobic digestion systems due to its high solids content. However, solid-state anaerobic digestion (SS-AD) provides an opportunity to generate methane from such high-solids feedstocks. This study was conducted to determine the influence of moisture content on the digestion of bedded pack dairy manure using SS-AD. Mixtures of sawdust bedding and dairy manure were prepared with moisture contents (MCs) of 70, 76, and 83% and digested at 37 °C for 85 days. The performance of digesters containing manure at 83% MC was 1.3 to 1.4-fold higher than that of digesters containing 70% MC manure in terms of volatile solids (VS) reduction and biogas production. VS reduction rates were 55 to 75% and cumulative methane yield ranged from 64 to 90 NmL (gVS)−1. These values are lower than those from SS-AD of fresh manure and this is likely due to the partial decomposition of biodegradable materials during the two to thr... [more]
Assessment of the Usefulness of the Twin-Screw Press in Terms of the Pressing Efficiency and Antioxidant Properties of Apple Juice
Kamil Wilczyński, Zbigniew Kobus, Rafał Nadulski, Marek Szmigielski
February 12, 2020 (v1)
Subject: Other
Keywords: antioxidant activity, ascorbic acid, hardness, mechanical properties, polyphenols, texture, twin-screw press
The paper presents the possibility of applying a twin-screw press for juice extraction from apples with different textural properties. The research was carried out with six different varieties; namely, Granny Smith, Modi, Ligol, Lobo, Boscop and Szampion. During the experiment, the following properties were measured: texture properties, pressing yield and polyphenolic content; and ascorbic acid content and antioxidant activity both in raw apples and apple juice. Based on the analysis, three hardness levels of apples can be distinguished, impacting the course of juice pressing in a twin-screw press (low hardness below 30 N, medium hardness 30−50 N and high hardness 50 N). The study showed that only high hardness apples are suitable for pressing on a twin-screw press. The mechanism by which texture properties influence the juice pressing process in the studied press was explained. It was further demonstrated that the hardness of apples has a positive impact on the degree of extraction of... [more]
Experimental Study on the Effect of Polymer Injection Timing on Oil Displacement in Porous Media
Leiting Shi, Shijie Zhu, Zhidong Guo, Wensen Zhao, Xinsheng Xue, Xiao Wang, Zhongbin Ye
February 12, 2020 (v1)
Subject: Other
Keywords: Buckley–Leverett equation, heavy oil, microscopic displacement, optimum polymer injection timing, residual oil distribution
It has been proven that polymer injection at early times is beneficial to offshore heavy oil recovery. It is of significant importance to optimize the polymer injection timing and decide the residual oil distribution after polymer flooding. Aiming at a specific offshore heavy oil reservoir in Bohai, China, the optimum polymer injection timing is investigated through laboratory experiments. The influence of polymer injection timing on oil displacement and remaining oil distribution is analyzed by combining macroscopic and microscopic flooding experiments. The results reveal that the optimum polymer injection timing should be close to the water breakthrough, i.e., just before the waterflooding front reaches the outlet of the core. In addition, the waterflooding front position is analytically solved by using the Buckley−Leverett method and verified by experimental results, which supply an approach to predict the polymer injection timing. When polymer is injected before the waterflood fron... [more]
Application and Mechanism of Sludge-Based Activated Carbon for Phenol and Cyanide Removal from Bio-Treated Effluent of Coking Wastewater
Yali Liu, Han Cheng, Yueting He
February 12, 2020 (v1)
Subject: Other
Keywords: activated carbon, adsorption kinetics, coking wastewater, municipal sludge
The toxic pollutants phenol and cyanide in the bio-treated effluent of coking wastewater still need advanced treatment to meet environmental requirements. In this study, activated carbon prepared from municipal sludge and bamboo waste (SBAC) was used for simultaneous adsorption of phenol and cyanide from bio-treated effluent of coking wastewater. The results showed that the optimum removal efficiencies of volatile phenol (69.7%) and total cyanide (80.1%) were observed at a SBAC dosage of 8 g/L, a pH value of 8.0, and a contact time of 80 min. The physical and chemical properties of SBAC were analyzed using Brunauer−Emmett−Teller (BET) surface area (SBET), scanning electron microscopy (SEM), and Fourier transform infrared (FTIR) spectroscopy. SBAC had high SBET (289.58 m2/g) and rich mesoporous structure (average pore diameter of 3.688 nm), and carboxylic groups on SBAC surfaces were enhanced due to the addition of bamboo waste. In addition, a kinetic model of pseudo-first-order fitted... [more]
Synthesis of the Hydrophobic Cationic Polyacrylamide (PADD) Initiated by Ultrasonic and its Flocculation and Treatment of Coal Mine Wastewater
Xin Qi, Junling Liu, Cheng Wang, Shiyao Li, Xiang Li, Yicong Liang, Khan Sarfaraz
February 12, 2020 (v1)
Subject: Other
Keywords: cationic polyacrylamide, coal mine wastewater, floc characteristics, flocculation, turbidity removal, ultrasonic initiation
In this study, a new type of hydrophobic cationic polyacrylamide P (AM-DMC-DABC) (PADD) was synthesized by ultrasonic (US)-initiated polymerization, which is used for the separation and removal of coal mine wastewater. The acrylamide (AM), methacryloyloxyethyl trimethyl ammonium chloride (DMC) and acryloyloxyethyl dimethylbenzyl ammonium chloride (DABC) were used as monomers to prepare). The factors that affecting the US initiated polymerization of PADD were analyzed. Fourier transform infrared spectroscopy (FT-IR), 1H nuclear magnetic resonance (1H NMR) and scanning electron microscopy (SEM) were used to characterize the chemical structure, thermal decomposition performance and surface morphology of the polymers. FT-IR and 1H NMR results showed that PADD was successfully synthesized. In addition, irregular porous surface morphology of PADD were observed by SEM analysis. Under the optimum conditions (pH = 7.0, flocculant dosage = 16.0 mg/L), the excellent flocculation performance (turb... [more]
Study of the Affinity Law of Energy and Cavitation Characteristics in Emergency Drainage Pumps at Different Rotating Speeds
Weidong Cao, Jiayu Mao
January 19, 2020 (v1)
Subject: Other
Keywords: affinity, cavitation, emergency drainage pump, rotating speed
The affinity law is widely used in pump design and experiments. The applicability of the affinity law in an emergency drainage pump at different rotating speeds was studied. Experiments and numerical simulation through ANSYS CFX (Computational Fluid Dynamics X) 15.0 software were used to research the affinity law characteristics. Results show that the simulation of characteristics is basically consistent with the experimental curves. In small flow rate conditions, due to the existence of obvious differential pressure between the pressure side and the suction side in the impeller blade tip area, the leakage flow occurs at the tip clearance, which collides with the main stream at the inlet and generates vortices at the leading edge of the impeller. The tip leakage flows of the pump at four different rotating speeds were compared, and it was found that the tip leakage increased with increasing rotation speed, and at the same rotation speed, the tip leakage flow was large in the small flow... [more]
Systematic Separation and Purification of Alkaloids from Euchresta tubulosa Dunn. by Various Chromatographic Methods
Wei-Xin Li, Huan Wang, Ai-Wen Dong
January 7, 2020 (v1)
Subject: Other
Keywords: alkaloids, chemical structures, chromatographic methods, Euchresta tubulosa Dunn., systematic separation
High-speed countercurrent chromatography (HSCCC) and silica gel column chromatography were used to separate and purify alkaloids from Chinese herbal medicine Euchresta tubulosa Dunn. The purpose of this study is to provide a system mode for rapid separation of alkaloids from natural products. In the experiment, the eluent of silica gel column chromatography was screened by thin layer chromatography (TLC) to obtain four components with different polarity. Then, the two-phase solvent systems of different components were selected and purified by HSCCC. Four alkaloids with relatively high content were obtained by this mode successfully, including matrine (28 mg), oxymatrine (32 mg), N-formyl cytisine (24 mg), and cytisine (58 mg). The purity was higher than 91% by high performance liquid chromatography−ultraviolet (HPLC-UV) and their chemical structures were identified by nuclear magnetic resonance (NMR) and electron ionization mass spectrometry (EI-MS). The results showed that the combina... [more]
Experimental Study on Spray Breakup in Turbulent Atomization Using a Spiral Nozzle
Ondřej Krištof, Pavel Bulejko, Tomáš Svěrák
January 7, 2020 (v1)
Subject: Other
Keywords: droplet size, droplet velocity, gas absorption, spiral nozzle, spray atomization
Spiral nozzles are widely used in wet scrubbers to form an appropriate spray pattern to capture the polluting gas/particulate matterwith the highest possible efficiency. Despite this fact, and a fact that it is a nozzle with a very atypical spray pattern (a full cone consisting of three concentric hollow cones), very limited amount of studies have been done so far on characterization of this type of nozzle. This work reports preliminary results on the spray characteristics of a spiral nozzle used for gas absorption processes. First, we experimentally measured the pressure impact footprint of the spray generated. Then effective spray angles were evaluated from the photographs of the spray and using the pressure impact footprint records via Archimedean spiral equation. Using the classical photography, areas of primary and secondary atomization were determined together with the droplet size distribution, which were further approximated using selected distribution functions. Radial and tan... [more]
Perfume Encapsulation via Vapor Induced Phase Separation
Mario Ammendola, Raul Rodrigo Gomez, Ricard Garcia Valls
January 2, 2020 (v1)
Subject: Other
Keywords: cellulose acetate, encapsulation, fragrance, sustainable, VIPS
In this study we explored the implementation of the vapor induced phase separation (VIPS) to produce cellulose acetate microcapsules for the encapsulation of a complex mix of fragrances. VIPS is a technique used for membrane preparation, but barely mentioned for microencapsulation. We compared the products from VIPS and a more common microencapsulation process, the immersion precipitation technique (IPS). The capsules prepared via VIPS show a core-shell structure with a thin polymeric shell surrounding the internally empty space, conversely to those produced via IPS, showing an incomplete spherical morphology. This can be attributed to a better control of the precipitation rate of the encapsulation material in the non-solvent thanks to the longer exposition time to the vapor. The activity and encapsulation efficiency of the capsules, obtained through TGA analysis, reached a maximum of ≈75% and ≈90%, respectively. Moreover, a growing trend between the initial active concentration and th... [more]
Evolution of High-Viscosity Gas−Liquid Flows as Viewed Through a Detrended Fluctuation Characterization
J. Hernández, D. F. Galaviz, L. Torres, A. Palacio-Pérez, A. Rodríguez-Valdés, J. E. V. Guzmán
December 16, 2019 (v1)
Subject: Other
Keywords: detrended fluctuation analysis, heavy oils, high-viscosity, two-phase flow
We characterize the long-term development of high-viscosity gas−liquid intermittent flows by means of a detrended fluctuation analysis (DFA). To this end, the pressures measured at different locations along an ad hoc experimental flow line are compared. We then analyze the relevant time-series to determine the evolution of the various kinds of intermittent flow patterns associated with the mixtures under consideration. Although no pattern transitions are observed in the presence of high-viscosity mixtures, we show that the dynamical attributes of each kind of intermittence evolves from one point to another within the transport system. The analysis indicates that the loss of a long-range correlation between the pressure responses are due to the discharge processes.
The Effect of Fines on Hydraulic Conductivity of Lawrencepur, Chenab and Ravi Sand
Tanveer Ahmed Khan, Khalid Farooq, Mirza Muhammad, Mudasser Muneer Khan, Syyed Adnan Raheel Shah, Muhammad Shoaib, Muhammad Asif Aslam, Syed Safdar Raza
December 16, 2019 (v1)
Subject: Other
Keywords: fines, fluid, permeability, sand, soil, transport
The amount of fines in sand greatly influence the permeability of sandy soils. Thus, this research was conducted to study the effect of plastic and non-plastic fines on the permeability of three types of sands (Lawrencepur sand, Chenab sand and Ravi sand). For this purpose, plastic and non-plastic fines were collected from different location of Lahore. Samples were prepared by mixing plastic and non-plastic fines into each type of sand separately, in amounts ranging from 0% to 50% with increments of five percent. Overall 63 samples were prepared. Sieve analysis and hydrometric analysis were performed to obtain particle size distribution for each sample. Atterberg’s limits were also determined and each sample was classified according to the Unified Soil Classification System (USCS). Compaction tests were performed on all samples as per the procedure in a standard Proctor test. The test samples were compacted in permeability molds with optimum moisture contents to obtain the density, as... [more]
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