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1.
Eng Life Sci ; 24(7): e2300243, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38975019

RESUMO

Shake flask cultivation, a cornerstone in bioprocess research encounters limitations in supplying sufficient oxygen and exchanging gases, restricting its accuracy in assessing microbial growth and metabolic activity. In this communication, we introduce an innovative gas supply apparatus that harnesses the rotational motion of a shaking incubator to facilitate continuous air delivery, effectively overcoming these limitations. We measured the mass transfer coefficient (kLa) and conducted batch cultures of Corynebacterium glutamicum H36LsGAD using various working volumes to assess its performance. Results demonstrated that the gas supply apparatus significantly outperforms conventional silicone stoppers regarding oxygen delivery, with kLa values of 2531.7 h-1 compared to 20.25 h-1 at 230 rpm. Moreover, in batch cultures, the gas supply apparatus enabled substantial improvements in microbial growth, maintaining exponential growth even at larger working volumes. Compared to the existing system, an increase in final cell mass by a factor of 3.4-fold was observed when utilizing 20% of the flask's volume, and a remarkable 9-fold increase was achieved when using 60%. Furthermore, the gas supply apparatus ensured consistent oxygen supply and efficient gas exchange within the flask, overcoming challenges associated with low working volumes. This approach offers a simple yet effective solution to enhance gas transfer in shake flask cultivation, bridging the gap between laboratory-scale experiments and industrial fermenters. Its broad applicability holds promise for advancing research in bioprocess optimization and scale-up endeavors.

2.
Environ Technol ; : 1-13, 2024 Jul 07.
Artigo em Inglês | MEDLINE | ID: mdl-38972296

RESUMO

ABSTRACTThe release of supersaturated total dissolved gas (STDG) from dams has been linked to the development of gas bubble disease, which can ultimately result in the death of fish. In order to minimize the impact of STDG on aquatic ecology, the effect of aeration on mass transfer at the air-liquid interface is taken into account. This paper selects four commonly used aerators to carry out indoor aeration tower experiments under different aeration conditions (aeration aperture, aeration water depth, and aeration volume), exploring aerators that can efficiently promote STDG release. The results indicated that the diaphragm aerator was found to have the greatest effect on STDG release, followed by corundum and spin mix aerator. In contrast, a pinhole aerator was found to have the least beneficial impact on STDG release. The increase in the release coefficient for the diaphragm aerator in comparison to the pinhole aerator is 32%. A prediction model for the aeration system was developed based on the mass transfer mechanism at the gas-liquid interface. The parameters in the model were determined using experimental data, which effectively improved the model's prediction accuracy. The findings of this study may serve as a reference point for the selection of the most suitable aerator in the actual engineering of STDG mitigation by aeration technology.

3.
Sci Rep ; 14(1): 16245, 2024 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-39009602

RESUMO

Chemical bioreactions play a significant role in many of the microfluidic devices, and their applications in biomedical science have seen substantial growth. Given that effective mixing is vital for initiating biochemical reactions in many applications, micromixers have become increasingly prevalent for high-throughput assays. In this research, a numerical study using the finite element method was conducted to examine the fluid flow and mass transfer characteristics in novel micromixers featuring an array of pillars. The study utilized two-dimensional geometries. The impact of pillar configuration on mixing performance was evaluated using concentration distribution and mixing index as key metrics. The study explores the effects of pillar array design on mixing performance and pressure drop, drawing from principles such as contraction-expansion and split-recombine. Two configurations of pillar arrays, slanted and arrowhead, are introduced, each undergoing investigation regarding parameters such as pillar diameter, gap size between pillar groups, distance between pillars, and vertical shift in pillar groups. Subsequently, optimal micromixers are identified, exhibiting mixing efficiency exceeding 99.7% at moderate Reynolds number (Re = 1), a level typically challenging for micromixers to attain high mixing efficiency. Notably, the pressure drop remains low at 1102 Pa. Furthermore, the variations in mixing index over time and across different positions along the channel are examined. Both configurations demonstrate short mixing lengths and times. At a distance of 4300 µm from the inlet, the slanted and arrowhead configurations yielded mixing indices of 97.2% and 98.9%, respectively. The micromixers could provide a mixing index of 99.5% at the channel's end within 8 s. Additionally, both configurations exceeded 90% mixing indices by the 3 s. The combination of rapid mixing, low pressure drop, and short mixing length positions the novel micromixers as highly promising for microfluidic applications.

4.
Environ Technol ; : 1-9, 2024 Jul 13.
Artigo em Inglês | MEDLINE | ID: mdl-39002156

RESUMO

Wet scrubbing technology is an effective emission control technology for marine diesel engines. Nitric oxide (NO) is one of the main component of ship emissions, the sodium persulfate (Na2S2O8) can facilitate the NO mass transfer process to a rapid reaction. Falling film reactors are widely used in rapid gas-liquid reactions, however, the reaction characteristics of denitrification using Na2S2O8 solution in a falling film reactor are not clear, which were investigated in this paper. The factors of NO mass transfer flux were tested with the liquid-gas ratio of 15 L/m3. The effects of solution properties and temperatures on the reaction driving force were studied by calculating the chemical reaction equilibrium constants and Gibbs free energy changes. The results showed that the NO mass transfer flux increased with the increase of temperature, Na2S2O8 concentration, O2 concentration and NO concentration. NO mass transfer flux increased by 41.00% and then decreased by 2.12% as the pH value increased from 7 to 10 and then rising to 12. The Gibbs free energy changes of alkaline solutions were 114.22%-130.99% lower than those of acidic solution at 303-343 K, and the chemical reaction equilibrium constants were higher. Na2S2O8/seawater system has great application potential in marine exhaust gas purification.

5.
Chemosphere ; 363: 142816, 2024 Jul 08.
Artigo em Inglês | MEDLINE | ID: mdl-38986787

RESUMO

3-chloro-4-fluoraniline (FCA) is an important intermediate for the synthesis of antibiotics, herbicides and insecticides, and has significant environmental health hazards. Catalytic hydrogenation technology is widely used in pretreatment of halogenated organics due to its simple process and excellent performance. However, compared with the research of high activity hydrogenation catalyst, the research of efficient utilization of hydrogen source under mild conditions is not sufficient. In this work, micro-nano H2 bubbles are produced in situ by electrolytic water and active metal replacement, and their apparent properties are studied. The result show that the H2 bubbles have a size distribution in the range of 150-900 nm, which can rapidly reduce the REDOX potential of the water and maintain it in a hydrogen-rich state for a long time. Under the action of Pd/C catalyst, atomic hydrogen (H•) produced by dissociative adsorption can sequentially hydrogenate FCA to aniline. The H• utilization ratios of the above two hydrogen supply pathways reach 6.20% and 4.94% respectively, and H2 consumption is reduced by tens of times (≥50 → ≈1.0 mL/min). The research provides technical support for the efficient removal of halogenated refractory pollutants in water and the development of hydrogen economy.

6.
Int J Biol Macromol ; : 133946, 2024 Jul 17.
Artigo em Inglês | MEDLINE | ID: mdl-39029825

RESUMO

The incorporation of active compounds into polymeric matrices using traditional methods has several drawbacks mainly due to the high volatility and thermal sensitivity of these substances. A solution to this problem could be the incorporation of bioactive compounds forming inclusion complexes as a strategy to improve the chemical stability, bioactivity and achieve controlled release. In this work, ß-cyclodextrin/carvacrol inclusion complex was prepared by spray drying to be incorporated into poly(lactic acid) (PLA) and Mater-Bi® films by supercritical CO2 impregnation. The impregnation process was carried out at pressures of 10, 15 and 20 MPa and at 40 °C. Both polymers showed the highest amount of incorporated inclusion complex at 15 MPa, where the percentage of impregnation varied from 0.6 % to 7.1 % in Mater-Bi® and PLA, respectively. Release tests for PLA films impregnated with inclusion complex showed a slow release of the active compound, which did not reach equilibrium after 350 h under the experimental conditions. This prolonged release was not observed in Mater-Bi® due to the lower incorporation of the inclusion complex. The release rate was described herein by a comprehensive phenomenological model considering the decomplexation kinetics combined with the equilibrium and mass transfer expressions.

7.
Sci Rep ; 14(1): 16529, 2024 Jul 17.
Artigo em Inglês | MEDLINE | ID: mdl-39019921

RESUMO

Flue gas emissions are the waste gases produced during the combustion of fuel in industrial processes, which are released into the atmosphere. These identical processes also produce a significant amount of wastewater that is released into the environment. The current investigation aims to assess the viability of simultaneously mitigating flue gas emissions and remediating wastewater in a bubble column bioreactor utilizing bacterial consortia. A comparative study was done on different growth media prepared using wastewater. The highest biomass yield of 3.66 g L-1 was achieved with the highest removal efficiencies of 89.80, 77.30, and 80.77% for CO2, SO2, and NO, respectively. The study investigated pH, salinity, dissolved oxygen, and biochemical and chemical oxygen demand to assess their influence on the process. The nutrient balance validated the ability of bacteria to utilize compounds in flue gas and wastewater for biomass production. The Fourier Transform-Infrared Spectrometry (FT-IR) and Gas Chromatography-Mass Spectrometry (GC-MS) analyses detected commercial-use long-chain hydrocarbons, fatty alcohols, carboxylic acids, and esters in the biomass samples. The nuclear magnetic resonance (NMR) metabolomics detected the potential mechanism pathways followed by the bacteria for mitigation. The techno-economic assessment determined a feasible total capital investment of 245.74$ to operate the reactor for 288 h. The bioreactor's practicability was determined by mass transfer and thermodynamics assessment. Therefore, this study introduces a novel approach that utilizes bacteria and a bioreactor to mitigate flue gas and remediate wastewater.


Assuntos
Biodegradação Ambiental , Biomassa , Reatores Biológicos , Águas Residuárias , Águas Residuárias/microbiologia , Águas Residuárias/química , Reatores Biológicos/microbiologia , Bactérias/metabolismo , Bactérias/crescimento & desenvolvimento , Gases/metabolismo , Espectroscopia de Infravermelho com Transformada de Fourier , Cromatografia Gasosa-Espectrometria de Massas
8.
Sci Rep ; 14(1): 16513, 2024 Jul 17.
Artigo em Inglês | MEDLINE | ID: mdl-39019972

RESUMO

The study of diffusion in biological materials is crucial for fields like food science, engineering, and pharmaceuticals. Research that combines numerical and analytical methods is needed to better understand diffusive phenomena across various dimensions and under variable boundary conditions within food matrices. This study aims to bridge this gap by examining the diffusion of substances through biological materials analytically and numerically, calculating diffusivity and conducting surface analysis. The research proposes a process for sweetening Bing-type cherries (Prunus avium) using sucrose/xylitol solutions and a staining technique utilising erythrosine and red gardenia at varying concentrations (119, 238 and 357 ppm) and temperatures (40, 50 and 60 °C). Given the fruit's epidermis resistance, the effective diffusivities of skin were inferior to those in flesh. Temperature and concentration synergise in enhancing diffusion coefficients and dye penetration within the food matrix (357 ppm and 60 °C). Red gardenia displayed significant temperature-dependent variation (p = 0.001), whereas erythrosine dye remained stable by temperature changes (p > 0.05). Gardenia's effective diffusivities in cherry flesh and skin, at 357 ppm and 60 °C, 3.89E-08 and 6.61E-09 m2/s, respectively, significantly differed from those obtained at lower temperatures and concentrations. The results highlight the temperature-concentration impacts on mass transfer calculations for food colouring processes and preservation methodologies.


Assuntos
Temperatura , Difusão , Frutas/química , Frutas/metabolismo , Eritrosina/química , Sacarose/química , Sacarose/metabolismo
9.
Water Res ; 262: 122101, 2024 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-39032329

RESUMO

Fluorinated pharmaceuticals pollution has become an ever-increasing environmental concern due to its negative impacts. Photoelectrocatalytic (PEC) degradation system is a desirable approach to tackle the pollution problems. However, photogenerated charge separation and interfacial mass transfer are the main bottlenecks for improving the PEC degradation performance. Herein, we report a TiO2 photoanode with tuned (101)/(110) facets in situ grown on a Ti mesh substrate for PEC degradation of fluorinated pharmaceuticals. The exposure of (101) facets facilitates efficient photogenerated charge separation and the desorption of generated •OH radical. Besides, the three-dimensional (3D) architecture of photoanode promotes macroscopic mass transfer. This system performed complete defluorination of 5-fluorouracil and more than 75 % total organic carbon (TOC) removal efficiency. The apparent reaction rate constant of high (101) facet-exposed TiO2 grown on Ti mesh is up to 6.96 h-1, 6‒fold faster than that of photoanode with low (101) facet-exposed TiO2 grown on Ti foil. It is demonstrated that a large-sized PEC system of 1200 cm2 can degrade 100 L of synthetic fluorinated pharmaceutical wastewater with more than 80 % elimination efficiency. This work showcases the facet and substrate modulated strategy of fabricating high-performed photoanode for PEC wastewater purification.

10.
Bioresour Technol ; 405: 130936, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38851597

RESUMO

Microbial fuel cell (MFC) is a promising device for water decontamination and energy generation. However, the correlation between power generation and pollutant degradation has not been clarified. Herein, a ruthenium-activated carbon (Ru-AC) bioanode was constructed for chlorobenzenes (CBs) treatment. The pollutant tolerance was improved by Ru-AC anode, and the minimum removal efficiencies of CB and ortho-dichlorobenzene (o-DCB) reached 75.1 % and 69.3 %, respectively, which were considerably higher than those of other MFCs (16.3 %-39.7 %). Correspondingly, the maximum output voltage reached 360.7 mV for the Ru-AC anode, whereas the values obtained from others reached 45.2-149.6 mV. Interaction models were introduced to quantify the relationship between power generation and pollutant degradation. The conversion of highly toxic chlorophenols to organic acids could be accelerated by boosting the mass and electron transfer, thereby simultaneously enhancing CBs removal and power generation. This work provided important insights into pollutant-powered MFC development.


Assuntos
Fontes de Energia Bioelétrica , Clorobenzenos , Eletrodos , Cinética , Poluentes Químicos da Água , Rutênio/química , Carvão Vegetal/química , Carvão Vegetal/farmacologia , Biodegradação Ambiental , Purificação da Água/métodos
11.
ACS Nano ; 18(27): 17361-17368, 2024 Jul 09.
Artigo em Inglês | MEDLINE | ID: mdl-38913031

RESUMO

Lithium-air batteries (LABs) have aroused worldwide interest due to their high energy density as a promising next-generation battery technology. From a practical standpoint, one of the most pressing issues currently in LABs is their poor rate performance. Accelerating the mass transfer rate within LABs is a crucial aspect for enhancing their rate capability. In this Perspective, we have meticulously analyzed the ion and oxygen transport processes to provide readers with a comprehensive understanding of the mass transfer within LABs. Following this, we have discussed potential misconceptions in the existing literature and propose our recommendations for improving the rate performance of LABs. This Perspective provides a deep insight into the mass transfer process in LABs and offers promising strategies for developing other high-rate metal-O2 batteries.

12.
Micromachines (Basel) ; 15(6)2024 Jun 20.
Artigo em Inglês | MEDLINE | ID: mdl-38930775

RESUMO

Acoustic levitation can provide significant benefits for many fundamental research questions. However, it is important to consider that the acoustic field influences the measurement environment. This work focuses on the dissolution of immobilised drops using acoustic levitation in liquid-liquid systems. Previous work demonstrated that the acoustic field of standing waves impacts mass transfer by affecting the spread of dissolved substances in the continuous phase in two distinct ways: (I) solutes may either pass through nodal planes of the standing waves or (II) not pass. The binary systems examined for case (I) are 1-hexanol-water and 1-butanol-water, and for case (II), n-butyl acetate-water and toluene-water. This work quantifies the intensification effect of acoustic levitation on dissolution for the two types of behaviour, by comparing them with reference measurements of mechanically attached dissolving drops. The system was designed to ensure minimal intensification. The minimum intensification of mass transfer for levitating drops in the used setup of case (I) was 25%, and for case (II), it was 65%, both increasing with decreasing surface-equivalent diameter. With this understanding, acoustic levitation can be used more accurately in the field of mass transfer studies.

13.
Foods ; 13(12)2024 Jun 17.
Artigo em Inglês | MEDLINE | ID: mdl-38928839

RESUMO

This study aims to optimize the frying process of natural porous materials (like potatoes) by enhancing heat and mass transfer phenomena through significant horizontal acceleration values following a spatially periodic pattern that alternates the intensity of inertia forces uniformly across the frying vessel. The generated horizontal inertial forces act complementary to the normal vertical buoyancy force for the creation of agitating convective currents in the oil and for vapor bubbles' departure from the surface of frying objects. The use of an innovative frying device, employing simultaneous rotation around two vertical axes at a different speed in a so-called planetary type of motion, serves to facilitate this production of horizontal acceleration values that allows intensifying the performance of frying. The present investigation examines the impact of rotational speed, along with oil temperature and frying duration, on the water loss and sensory evaluation of fried items. The potato-to-oil ratios typically found in industrial frying operations are employed. The intended outcome is a more energy-efficient frying process, reduced cooking times, and a healthier product due to lower frying temperatures and the consequent decreased formation of harmful compounds. This approach carries substantial implications for food processing, potentially enhancing productivity while limiting operational costs.

14.
ACS Appl Mater Interfaces ; 16(27): 35208-35216, 2024 Jul 10.
Artigo em Inglês | MEDLINE | ID: mdl-38936813

RESUMO

The unsatisfactory oxygen reduction reaction (ORR) kinetics caused by the inherent lean-oxygen marine environment brings low power density for metal-dissolved oxygen seawater batteries (SWBs). In this study, we propose a seawater/electrode interfacial engineering strategy by constructing a hydrophobic coating to realize enhanced mass transfer of dissolved oxygen for the fully immersed cathode of SWBs. Accumulation of dissolved oxygen from seawater to the catalyst is particularly beneficial for improving the ORR performance under lean-oxygen conditions. As a result, SWB assembled with a hydrophobic cathode achieved a power density of up to 2.32 mW cm-2 and sustained discharge at 1.3 V for 250 h. Remarkably, even in environments with an oxygen concentration of 4 mg L-1, it can operate at a voltage approximately 100 mV higher than that of an unmodified SWB. The introduction of a hydrophobic interface enhances the discharge voltage and power of SWBs by improving interfacial oxygen mass transfer, providing new insights into improving the underwater ORR performance for practical SWBs.

15.
Waste Manag ; 186: 35-45, 2024 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-38852375

RESUMO

The active graphite felt (GF) catalytic layer was effectively synthesized through a wet ultrasonic impregnation-calcination method, modified with CB and PTFE, and implemented in a pioneering side-aeration electrochemical in-situ H2O2 reactor. The optimal mass ratio (CB: PTFE 1:4) for the modified cathode catalytic layer was determined using a single-factor method. Operating under optimum conditions of initial pH 5, 0.5 L/min air flow, and a current density of 9 mA/cm2, the system achieved a remarkable maximum H2O2 accumulation of 560 mg/L, with the H2O2 production capacity consistently exceeding 95 % over 6 usage cycles. The refined mesoporous structure and improved three-phase interface notably amplified oxygen transfer, utilization, and H2O2 yield. Side aeration led to an oxygen concentration near the cathode reaching 20 mg/L, representing a five-fold increase compared to the 3.95 mg/L achieved with conventional bottom aeration. In the final application, the reaction system exhibited efficacy in the degradation of landfill leachate concentrate. After a 60-minute reaction, complete removal of chroma was attained, and the TOC degradation rate surpassed 60 %, marking a sixfold improvement over the conventional system. These results underscore the substantial potential of the system in H2O2 synthesis and environmental remediation.


Assuntos
Eletrodos , Peróxido de Hidrogênio , Poluentes Químicos da Água , Peróxido de Hidrogênio/química , Poluentes Químicos da Água/química , Técnicas Eletroquímicas/métodos , Catálise , Grafite/química , Oxigênio/química
16.
J Environ Sci (China) ; 145: 216-231, 2024 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-38844321

RESUMO

Catalytic ozonation is an effective wastewater purification process. However, the low ozone mass transfer in packed bubble columns leads to low ozone utilization efficiency (OUE), poor organic degradation performance, and high energy consumption. Therefore, there is an urgent need to develop efficient supported catalysts that can enhance mass transfer and performance. However, the reaction mechanism of the support on ozone mass transfer remains unclear, which hinders the development of catalytic ozonation applications. In this study, lava rocks (LR)-supported catalysts, specifically CuMn2O4@LR and MnO2Co3O4@LR, were proposed for catalytic ozonation of IBP degradation due to their superior catalytic activity, stability, and high OUE. Addition of CuMn2O4@LR or MnO2Co3O4@LR increased IBP removal efficiency from 85% to 91% or 88%, and reduced energy consumption from 2.86 to 2.14 kWh/m3 or 2.60 kWh/m3, respectively. This improvement was attributed to LR-supported catalysts enhancing mass transfer and promoting O3 decomposition to generate •OH and •O2-, leading to IBP degradation. Furthermore, this study investigated the effects of ozone dose, supporter sizes, and catalyst components on ozone-liquid mass transfer. The results revealed that the size of the supporter influenced stacked porosity and consequently affected ozone mass transfer. Larger-sized LR (kLa= 0.172 min-1) exhibited better mass transfer compared to smaller-sized supports. Based on these findings, it was concluded that both CuMn2O4@LR and MnO2Co3O4@LR are potential catalysts for catalytic ozonation in residual IBP degradation of pharmaceutical wastewater, and LR showed good credibility as a catalyst supporter. Understanding the effects of supporters and active components on ozone mass transfer provides a fundamental principle for designing supported catalysts in catalytic ozonation applications.


Assuntos
Ibuprofeno , Ozônio , Eliminação de Resíduos Líquidos , Poluentes Químicos da Água , Ozônio/química , Catálise , Poluentes Químicos da Água/química , Ibuprofeno/química , Eliminação de Resíduos Líquidos/métodos , Águas Residuárias/química , Purificação da Água/métodos
17.
J Hazard Mater ; 476: 134979, 2024 Jun 19.
Artigo em Inglês | MEDLINE | ID: mdl-38905982

RESUMO

Spatially confined structure exhibits surprising physics and chemistry properties that significantly impact the thermodynamics and kinetics of oxidation reactions. Herein, porous carbons are rationally designed for tunable nanopore structures (micropores, 4.12 % ∼ 91.64 %) and diverse spatial confinement ability, as indicated by their differential enhancement performances in the Fenton oxidation. Porous carbons can alter the characteristics of the charge transport process for accelerating sustainable electron shuttle between hydrogen peroxide and iron species, and thus exhibit long-term performance (17 cycling tests). The positive spatial confinement for boosting Fenton oxidation (charge transport, mass transfer) occurs in nanochannels < 1 nm, while the diminished effect ranges of 1-1.5 nm, and the adverse effect ranges greater than 1.5 nm. The density functional theory calculation provides further support for certifying the promoted charge transport process and spatial confinement for hydroxyl radical inside the confined nanochannel structure (below 1 nm, especially) by the comparatively large electron cloud and the relatively negative adsorption energy, respectively. Coupling nanochannels with the Fenton oxidation greatly utilize hydrogen peroxide, due to spatial nanoconfinement and selective adsorption towards target contaminants. This strategy of deploying nanochannels in catalyst design can be applied for the elaborate construction of efficient nanostructured catalysts for environmental remediation.

18.
Chemosphere ; 362: 142540, 2024 Jun 06.
Artigo em Inglês | MEDLINE | ID: mdl-38851514

RESUMO

The rate of mass transfer of lower molecular weight hydrocarbons (naphtha) from bitumen drops in mature fine tailings of oil sand tailings ponds (OSTPs) may control their bioavailability and the associated rate of GHG production. Experiments were conducted using bitumen drops spiked with o-xylene and 1-methylnaphthalene to determine the mass transfer rate of these naphtha components from bitumen drops. The results were compared to simulations using a multi-component numerical model that accounted for transport in the drop and across the oil-water interface. The results demonstrate rate-limited mass transfer, with aqueous concentrations after 60 days of dissolution that were different than those in equilibrium with the initial drop composition (less for o-xylene and greater for 1-methylnaphthalene). The simulations suggest that mole fractions were unchanged at the center of the drop, resulting in concentration gradients out to the oil-water interface. Numerical simulations conducted using different drop sizes and bitumen viscosities also suggest the potential for persistent naphtha dissolution, where the time required to deplete 80% of the o-xylene and 1-methylnaphthalene mass from an oil drop was estimated to be on the order of months to years for mm-sized drops, and years to decades for cm-sized drops assuming instantaneous biodegradation in the aqueous phase surrounding the bitumen.

19.
Foods ; 13(11)2024 May 25.
Artigo em Inglês | MEDLINE | ID: mdl-38890887

RESUMO

This study investigates the applicability of the Peleg model to the osmotic dehydration of various sweet potato variety samples in sugar beet molasses, addressing a notable gap in the existing literature. The osmotic dehydration was performed using an 80% sugar beet molasses solution at temperatures of 20 °C, 35 °C, and 50 °C for periods of 1, 3, and 5 h. The sample-to-solution ratio was 1:5. The objectives encompassed evaluating the Peleg equation's suitability for modeling mass transfer during osmotic dehydration and determining equilibrium water and solid contents at various temperatures. With its modified equation, the Peleg model accurately described water loss and solid gain dynamics during osmotic treatment, as evidenced by a high coefficient of determination value (r2) ranging from 0.990 to 1.000. Analysis of Peleg constants revealed temperature and concentration dependencies, aligning with previous observations. The Guggenheim, Anderson, and de Boer (GAB) model was employed to characterize sorption isotherms, yielding coefficients comparable to prior studies. Effective moisture diffusivity and activation energy calculations further elucidated the drying kinetics, with effective moisture diffusivity values ranging from 1.85 × 10-8 to 4.83 × 10-8 m2/s and activation energy between 7.096 and 16.652 kJ/mol. These findings contribute to understanding the complex kinetics of osmotic dehydration and provide insights into the modeling and optimization of dehydration processes for sweet potato samples, with implications for food processing and preservation methodologies.

20.
ChemSusChem ; : e202400963, 2024 Jun 26.
Artigo em Inglês | MEDLINE | ID: mdl-38926939

RESUMO

The liquid-phase mass transport is the key factor affecting battery stability. The influencing mechanism of liquid-phase mass transport in the separators is still not clear, the internal environment being a complex multi-field during the service life of lithium-ion batteries. The liquid-phase mass transport in the separators is related to the microstructure of the separator and the physicochemical properties of electrolytes. Here, in-situ local electrochemical impedance spectra were developed to investigate local inhomogeneities in the mass transfer process of lithium-ion batteries. The geometric microstructure of the separator affects the mass transfer process, with a reduction in porosity leading to increased overpotentials. There is a competitive relationship among porosity, tortuosity, and membrane thickness in the geometric parameters of the separator, resulting in a peak of polarization. The resistance of the liquid-phase mass transfer process is positively correlated with the viscosity of the electrolyte, making ion migration difficult due to high viscosity. Polarization is closely related to the electrochemical performance, so a phase diagram of battery performance and inhomogeneous mass transfer was developed to guide the design of the battery. This study provides a guiding basis for the development of high stability lithium-ion batteries.

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