A recently proposed moving-boundary model for food isothermal dehydration was applied to analyze the dehydration kinetics of ellipsoidal cocoa beans, characterized by a moderate shrinkage and a non-uniform initial distribution of water content between the core and the shell of the bean. The aim is to predict the influence of air velocity and non-uniformity of the initial water distribution on the dehydration rates, as well as the temporal evolution of the water content in the core and in the shell and of the characteristic lengths of the ellipsoidal bean. The model proved capable of accurately describing the two-phases dehydration process: an initial fast dehydration of the shell, characterized by higher dehydration rates, followed by a slower dehydration of the core, characterized by a linear relationship j d = δ ( T ) X r between the dehydration rate j d and the moisture ratio X r . A shortcut method to estimate the effective water diffusivity D is also p... [more]

A well-known bioseparation technique namely liquid biphasic system (LBS) has attracted many researchers’ interest for being an alternative bioseparation technology for various kinds of biomolecules. The present review begins with an in-depth discussion on the fundamental principle of LBS and this is followed by the discussion on further development of various phase-forming components in LBS. Additionally, the implementation of various advance technologies to the LBS that is beneficial towards the efficiency of LBS for the extraction, separation, and purification of biomolecules was discussed. The key parameters affecting the LBS were presented and evaluated. Moreover, future prospect and challenges were highlighted to be a useful guide for future development of LBS. The efforts presented in this review will provide an insight for future researches in liquid-liquid separation techniques.

Creosote oil, widely used as a wood preservative, is a complex mixture of different polycyclic aromatic compounds. The soil contamination result in the presence of a specific microcosm. The presented study focuses on the most active strains involved in bioremediation of long-term creosote-contaminated soil. In three soil samples from different boreholes, two Sphingomonas maltophilia (S. maltophilia) and one Paenibacillus ulginis (P. ulginis) strain were isolated. The conducted experiments showed the differences and similarities between the bacteria strains capable of degrading creosote from the same contaminated area. Both S. maltophilia strains exhibit higher biodegradation efficiency (over 50% after 28 days) and greater increase in glutathione S-transferase activity than P. ulginis ODW 5.9. However, S. maltophilia ODW 3.7 and P. ulginis ODW 5.9 were different from the third of the tested strains. The growth of the former two on creosote resulted in an increase in cell adhesion to Con... [more]

An advanced algorithm has been developed in order to analyze the performance of re-boiling process of crude oil flowing inside reboilers tubes. The proposed model is composed from Heptane fire heater and a tube array. The heat flux produced from burner is transferred to the crude oil flowing inside the tube. The computational model is composed of two phases—Simulation of fire by using Fire Dynamics Simulator software (FDS) version 5.0 and then a nucleate boiling computation of the crude oil. FDS code is formulated based on CFD (Computational Fluid Dynamics) of fire heater. The thermo-physical properties (such as: thermal conductivity, heat capacity, surface tension, viscosity) of the crude oil were estimated by using empirical correlations. The thermal heat transfer to evaporating two-phase crude oil mixture occur by bubble generation at the wall (nucleate boiling) has been calculated by using Chen correlation. It has been assumed that the overall convective heat transfer coefficient i... [more]

In this work, the cocoa pod husk (CPH) was converted into biochar products at higher carbonization temperatures (i.e., 400−800 °C). The pore and chemical properties of the resulting biochars and its post-leaching biochars by acid washing, including specific surface area, total pore volume, pore size distribution, true density, and scanning electron microscopy-energy dispersive X-ray spectroscopy (SEM-EDS) and Fourier Transform infrared spectroscopy (FTIR) were studied. Based on the pore properties, pyrolysis temperature at around 800 °C seemed to have the most profound impact on the pore development for producing biochar, where its Brunauer−Emmet−Teller (BET) surface area is 101 m2/g. More noticeably, more pores in the CPH-based biochar could be significantly created during the acid-washing, resulting in an increase of BET surface area from 101 to 342 m2/g. According to the data on the EDS and FTIR, the resulting biochars seemed to have oxygen-containing functional groups on the surfac... [more]

Usage of a wide-angle diffuser may result in unfavorable separated flow and a significant diffuser loss. To improve the performance of the diffusers, inserting short splitter vanes is known as a useful method that has been demonstrated experimentally. Regarding the role of the vane in the diffuser flow, Senoo & Nishi (1977) qualitatively explained that the lift force acting on the vane should be a key factor. However, its quantitative verification remains since then. To challenge this issue, numerical simulations of incompressible flow in a wide angle of 28° two-dimensional diffuser with and without a short splitter vane were conducted in the present study. An improvement of pressure-recovery by the vane and oscillatory flows in the diffuser are reasonably reproduced from comparison with the experimental results made by Cochran & Kline (1958). It is also found that the lift force acting on the vane varies periodically in an opposite phase with the detachment point moved back and forth... [more]

Agriculture is one of the leading sectors on the global level contributing to greenhouse gas (GHG) emissions increase. With the utilization of biogas production technology within the agriculture sector, ecological benefits could be achieved, with immediate economic profit. Therefore, to retain economic profit and environmental sustainability, implementation of bioeconomy principles is of key importance. This paper examines four options of digestate treatment, which is identified as one of the highest operational cost for the biogas plant. A simple and robust model in Excel Solver was developed to determine the best solution for minimising GHG emissions and maximise profit for the biogas plant operator, through an upgrade of the plant with digestate treatment technologies. The model was implemented on a case of a Croatian biogas plant and the best solution in terms of GHG reduction and profit increase proved to be fertilizer production (Option 1), through a crystallization process of st... [more]

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 [...]

The following research utilizes Multi-Criteria Decision Making (MCDM) in order to build a business strategy to reduce product costs, improve competitiveness, focus on production planning based on actual operating capacity and flexible adjustment according to the market, maximize the labor productivity of technology workshops, reduce costs and inventory, and focus on producing many petrochemical products and products of high economic value. Selecting the right materials supplier is of paramount importance to the success of the organization as a whole. Supplier evaluation and the selection of a suitable supplier is a complex problem in which the decision maker must consider both qualitative and quantitative factors. Multi-Criteria Decision Making Models are an effective tool used to solve complex selection issues including multiple criteria and options, especially for qualitative variables. Thus, the author proposes an MCDM model including the Supply Chain Operation Reference (SCOR) mode... [more]

The use of humic-like substances, zeolites, various porous oxides (i.e., Al, Fe, or Si oxides), and magnetic nanocomposites in the adsorption of agrochemicals from water was critically reviewed. Firstly, the adsorbents were characterized from the structural, textural, and physico-chemical points of view. Secondly, the fundamental aspects of the adsorption of various agrochemicals on the solids (dependence on pH, kinetics, and isotherm of adsorption) were studied and interpreted on the basis of the adsorbent features. Thirdly, iterative processes of agrochemical removal from water by adsorption on the reported solids were described. In particular, in some cases the residual concentration of agrochemicals in water was lower than the maximum concentration of agrochemicals that the Italian regulations allow to be released in wastewater, surface waters, or sink water.

Offshore floating hybrid wind and wave energy is a young technology yet to be scaled up. A way to reduce the total costs of the energy production process in order to ensure competitiveness in the sustainable energy market is to maximize the farm’s efficiency. To do so, an energy generation and costs calculation model was developed with the objective of minimizing the technology’s Levelized Cost of Energy (LCOE) of the P80 hybrid wind-wave concept, designed by the company Floating Power Plant A/S. A Particle Swarm Optimization (PSO) algorithm was then implemented on top of other technical and decision-making processes, taking as decision variables the layout, the offshore substation position, and the export cable choice. The process was applied off the west coast of Ireland in a site of interest for the company, and after a quantitative and qualitative optimization process, a minimized LCOE was obtained. It was then found that lower costs of ~73% can be reached in the short-term, and th... [more]

Polyphenols, obtained from natural resources, may possess important pharmacological effects. The polyphenolic profiles of the stem extracts of six Ferocactus species (sp.): F. gracilis, F. pottsii, F. herrerae, F. horridus, F. glaucescens, and F. emoryi, were measured using high-performance liquid chromatography (HPLC) with diode-array detection (DAD). Additionally, anticancer, antibacterial, and antifungal activities were examined. Results showed the presence of high to moderate amounts of polyphenols in the extracts (phenolic acids: Protocatechuic acid, 3,4-dihydroxyphenylacetic acid, caffeic acid, and vanillic acid; flavonoids: Rutoside and quercitrin). The highest amounts of 3,4-dihydroxyphenylacetic acid were found in F. glaucescens ((132.09 mg 100 g−1 dry weight (DW)), F. pottsii (75.71 mg 100 g−1 DW), and F. emoryi (69.14 mg 100 g−1 DW) while rutoside content was highest in F. glaucescens (107.66 mg 100 g−1 DW). Maximum antiproliferative activities were observed against HeLa and... [more]

By monitoring the real-time gas production (CO2 and H2) and redox potential at high sampling frequency in continuous culture of Clostridium pasteurianum on glycerol as sole carbohydrate, the self-synchronized oscillatory metabolism was revealed and studied. The oscillations in CO2 and H2 production were in sync with each other and with both redox potential and glycerol in the continuous stirred tank reactor (CSTR). There is strong evidence that the mechanism for this is in the regulation of the oxidative pathway of glycerol metabolism, including glycolysis, and points toward complex, concerted cycles of enzyme inhibition and activation by pathway intermediates and/or redox equivalents. The importance of understanding such an “oscillatory metabolism” is for developing a stable and highly productive industrial fermentation process for butanol production, as unstable oscillations are unproductive. It is shown that the oscillatory metabolism can be eradicated and reinstated and that the pe... [more]

CFD simulation and analysis of the internal flow field of the annular multi-nozzle jet pump are carried out to study the effects of nozzle section geometries on performance of the pump based on the finite volume method and realizable k-ε model. The results show that the square nozzle peak efficiency is 3% higher than that of the circular nozzle and 4.1% higher than that of the triangular nozzle. According to the simulation results, the mixing mechanism of the working fluid and second fluid is analyzed on the basis of the vortex dynamics. The results show the following: the recirculation area and the friction loss of the non-circular nozzle are reduced, and the mixing effect is improved; the streamwise vortex plays a major role in the mixing process and decays to an extremely small value at the end of the throat after attenuating rapidly in the suction chamber; compared with the streamwise vortex, the strength of the spanwise vortex is relatively stronger; the spanwise vortex still fluc... [more]

High rate activated sludge (HRAS) processes have a high potential for carbon and energy recovery from sewage, yet they suffer frequently from poor settleability due to flocculation issues. The process of flocculation is generally optimized using jar tests. However, detailed jar hydrodynamics are often unknown, and average quantities are used, which can significantly differ from the local conditions. The presented work combined experimental and numerical data to investigate the impact of local hydrodynamics on HRAS flocculation for two different jar test configurations (i.e., radial vs. axial impellers at different impeller velocities) and compared the hydrodynamics in these jar tests to those in a representative section of a full scale reactor using computational fluid dynamics (CFD). The analysis showed that the flocculation performance was highly influenced by the impeller type and its speed. The axial impeller appeared to be more appropriate for floc formation over a range of impell... [more]

The chemical composition and properties of seed oils have attracted researchers nowadays. By this meaning, the physicochemical and bioactivity profile of prickly pear seed oil (PPSO) (a product of prickly pear fruits waste) were investigated. Seeds of shelf-grown cactus fruits (Opuntia ficus indica L.) were subjected to analysis. Moisture content (gravimetric analysis), seed content (gravimetric analysis), oil yield (Soxhlet extraction/gravimetric analysis), volatile compounds (HS-SPME/GC-MS), fatty acids profile (GC-FID), in vitro antioxidant activity (DPPH assay), and total phenolic content (Folin-Cioacalteu assay) were determined. Results showed that prickly pear seeds had a moisture content of 6.0 ± 0.1 g/100 g, whereas the oil yield ranged between 5.4 ± 0.5 g/100 g. Furthermore, the PPSO had a rich aroma because of acids, alcohols, aldehydes, esters, hydrocarbons, ketones, and other compounds, with the major volatiles being 2-propenal, acetic acid, pentanal, 1-pentanol, hexanal, 2... [more]

Biochar obtained from sewage sludges are adopted for biogas cleaning. Sewage sludges are treated considering temperature, dwell time, activating agent, heating, and flow rate. The best performances achieved are registered considering the char produced at 400 °C using CO2 as an activating agent with a dwell time of 2 h. The adsorption capacity for the biogas cleaning CH4/CO2/H2S (20 ppm(v)) increased from 1.3 mg/g to 5.9 mg/g with the bed height. Future research with chemical activation processes will be made to improve the adsorption capacity achieved to produce cheaper sorbents than commercial ones.

Curcumin (CUR) has been used since ancient times to treat several ailments as it possesses many pharmacological activities. This study intended to explore the mechanism underlying the protective effects of CUR in remodeling oxidative stress and apoptotic signals in cyclophosphamide (CP)-induced pulmonary injury in albino rats. CUR was administered at a dose of 300 mg/kg/day for 7 days and on the seventh day a single dose of CP (200 mg/kg) was given. Histopathological and ultrastructural examinations of CP-intoxicated rats showed complete alveolar obstruction, thickened inter-alveolar septa, enlarged blood vessels, severe inflammatory edema with pyknotic nuclei, and disappearance of cytoplasmic organelles. Significant increases in caspase-3, malondialdehyde (MDA), and protein carbonyl (PCO) and significant decreases in superoxide dismutase (SOD) and glutathione peroxidase (GPx) were observed. In contrast, rats that received CUR showed clear and empty lumina with single row of pneumocyte... [more]

The propagation of cascading failures of modern power systems is mainly constrained by the network topology and system parameter. In order to alleviate the cascading failure impacts, it is necessary to adjust the original network topology considering the geographical factors, construction costs and requirements of engineering practice. Based on the complex network theory, the power system is modeled as a directed graph. The graph is divided into communities based on the Fast−Newman algorithm, where each community contains at least one generator node. Combined with the islanding characteristics and the node vulnerability, three low-degree-node-based link-addition strategies are proposed to optimize the original topology. A new evaluation index combining with the attack difficulty and the island ratio is proposed to measure the impacts on the network under sequential attacks. From the analysis of the experimental results of three attack scenarios, this study adopts the proposed strategie... [more]

The volatile constituents of the essential oil of local Pelargonium graveolens growing in Egypt was investigated by gas chromatography−mass spectrometry (GC−MS), and the main constituents were citronellol (27.67%), cis-Menthone (10.23%), linalool (10.05%), eudesmol (9.40%), geraniol formate 6.87%, and rose oxide (5.77%), which represent the major components in the obtained GC total ion chromatogram. The structural determination of the main constitutes based on their electron ionization mass spectra have been investigated. The MS of these compounds are absolutely identical in mass values of peaks of fragment ions, where their relative intensities have minor differences. In the spectra of all studied compounds, the observed characteristic ions were [M-H2O]+ and [M-CH3]+. The latter has a structure with m/z 69, 83. Different quantum parameters were obtained using Modified Neglect of Diatomic Overlap (MNDO) semi-empirical method as total energy, binding energy, heat of formations, ionizati... [more]

Ice cream viscosity is one of the properties that most changes during crystallization in scraped surface heat exchangers (SSHE), and its online measurement is not easy. Its estimation is necessary through variables that are easy to measure. The temperature and power of the stirring motor of the SSHE turn out to be this type of variable and are closely related to the viscosity. Therefore, a mathematical model based on these variables proved to be feasible. The development of this mathematical relationship involved the rheological study of the ice cream base, as well as the application of a method for its in situ melting in the rheometer as a function of the temperature, and the application of a mathematical model correlating the SSHE stirring power and the ice cream viscosity. The result was a coupled model based on both the temperature and stirring power of the SSHE, which allowed for online viscosity estimation with errors below 10% for crystallized systems with a 30% ice fraction at... [more]

Mathematical model simulation is a useful method for understanding the complex behavior of a living system. The construction of mathematical models using comprehensive information is one of the techniques of model construction. Such a comprehensive knowledge-based network tends to become a large-scale network. As a result, the variation of analyses is limited to a particular kind of analysis because of the size and complexity of the model. To analyze a large-scale regulatory network of neural differentiation, we propose a contractive method that preserves the dynamic behavior of a large network. The method consists of the following two steps: comprehensive network building and network reduction. The reduction phase can extract network loop structures from a large-scale regulatory network, and the subnetworks were combined to preserve the dynamics of the original large-scale network. We confirmed that the extracted loop combination reproduced the known dynamics of HES1 and ASCL1 before... [more]

The paper presents a practical algorithm of the proportional-internal model control (P-IMC) type that can be applied to control a wide class of processes: Stable proportional processes, integral processes and some unstable processes. The P-IMC algorithm is a suitable combination between the P0-IMC algorithm and the P1-IMC algorithm, which are characterized by a too weak and a too strong impact of the tuning gain on the control action, respectively. The overall controller has five parameters: A tuning parameter K, three model parameters (steady-state gain, settling time, and time delay) and a process feedback gain used only for integral or unstable processes, to turn them into a compensated process (stable and of proportional type). For a step setpoint, the initial value of the compensated process input is approximately K times its final value. Furthermore, for K = 1 , the compensated process input is close to a step shape (step control principle). These properties enable a human... [more]

To implement the quality-relevant monitoring scheme for batch processes with multiple output modes, this paper presents a novel methodology based on stochastic programming. Bringing together tools from stochastic programming and ensemble learning, the developed methodology focuses on the robust monitoring of process quality-relevant variables by taking the stochastic nature of batch process parameters explicitly into consideration. To handle the problem of missing data and lack of historical batch data, a bagging approach is introduced to generate individual quality-relevant sub-datasets, which are used to construct the corresponding monitoring sub-models. For each model, stochastic programming is used to construct an optimal quality trajectory, which is regarded as the reference for online quality monitoring. Then, for each sub-model, a corresponding control limit is obtained by computing historical residuals between the actual output and the optimal trajectory. For online monitoring,... [more]

A solid oxide fuel cell (SOFC) is an electrochemical cell that converts chemical energy into electrical energy by oxidizing fuel. SOFC has high efficiency and cleans oxidation residues. Research has shown the importance of SOFC control. Voltage output control is needed because of nonlinearity, slow dynamics, and proper SOFC operating restrictions. This study aims to design an SOFC simulator with output voltage control to optimize the flow rate of fuel (hydrogen) and air (oxygen). This SOFC simulator is designed based on a microcontroller model. The controller is designed using the fuzzy logic method. Tests show that the output voltage can approach the set point with an average of 340.6 volts. The pressure difference (∆Pressure) between the two gases averaged 4428 Pa, and the fuel/gas flow rate was in the range of 0.7 mol/s. The controller can correct both the output voltage of the SOFC simulator and the difference in gas pressure under 8106 Pa (0.08 atm).