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Biorefining biological waste to produce eco-friendly fuels and by-products is essential in transitioning from non-renewable energies. However, the analysis of the processes in the laboratory necessitates a substantial investment of both time and money. The present study has developed machine learning (ML) models for evaluating biofuel products through glycerol biorefining for the first time. This study evaluates the performance of different ML algorithms, including recurrent neural network (RNN), random forest (RF), adaptive boosting (AdaBoost), Bayesian ridge (BR), and elastic net linear regression (ENLR). This research by machine learning algorithms can be created the formulas and the models for the hydrogen content (H 2) by the hydrogen production and time, the hydrogen production by the H 2 and time, OLR by PH and time, OLR by the hydrogen production and time, and the hydrogen production by OLR and time. Using the RNN for predicting the future of H 2 , hydrogen production, and OLR with the least error. The best R-Squared for the formulas is between 0.951 and 0.994 with the linear and the polynomial forms (by degrees 2, 3, 4). The best R-Squared for the models is between 0.998 and 0.999 with the linear form. MAEs for the formula and the model of H 2, respectively, are 2.475347126 and 0.46588143, and MAEs for the formula and the model of the hydrogen production, respectively, are 23.44120285 and 7.03283978. MAEs of OLR by PH and OLR by the hydrogen production for formulas and models are 2.095157 and 000001 by PH and 3.148667 and 0.000001 by the hydrogen production. MAEs for the formula and the model of the hydrogen production by OLR, respectively, are 19.025255 and 2.718604. • Development of machine learning models for evaluating biofuel products through glycerol biorefining. • Evaluation of different ML algorithms in predicting hydrogen production, H 2 content, and organic loading rate in the biorefining process. • Creation of formulas and models for H 2 content, hydrogen production, and OLR by various factors. • Use of RNN for predicting the future of H 2 content, hydrogen production, and OLR with the least error. • Best R-Squared for the models is between 0.998 and 0.999 with the linear form. [ABSTRACT FROM AUTHOR]

Load managing and price optimizer are significant elements in triple models and combined cooling, heating, and power (CCHP) models. In this study, a new CCHP model utilizes a fuel cell as the main drive with a heat recovery system, a 5-kW PEMFC pile, a small immersion chiller, a humidifier, and a gas compressor is considered. The system has been assessed regards to environment, thermodynamics, and economics in terms of view. A developed type of Honey Badger Optimizer has been suggested to optimize the effectiveness of the model. The system productivity has been assessed by the exergy, energy, yearly price, and pollutant release decrease. According to model studies, low operating temperatures, high intake gas pressures, and high relative humidity all contribute to improved system efficiency and a reduction in greenhouse gas emissions. Based on simulation data, the electricity efficiency at the final optimized point is found to be 69.77%, which is a significant improvement over the baseline efficiency of 63.3% before optimization. Furthermore, the optimized system resulted in a yearly reduction of greenhouse gas emissions by 1.47e7 g, which represents a notable improvement over the 1.20e7 g reduction achieved by the standard system. • New CCHP model is proposed for a fuel cell as the main drive with heat recovery system. • System is analyzed based on environment, thermodynamics, and economics terms of view. • Developed version of Honey Badger Optimizer to improve the system efficiency. • Productivity is by the energy, exergy, yearly price, and pollutant release decrease. [ABSTRACT FROM AUTHOR]

This article has been retracted: please see Elsevier Policy on Article Withdrawal (https://www.elsevier.com/about/policies/article-withdrawal). Post-publication, the editor discovered suspicious changes in authorship between the original submission and the revised version of this paper. In summary, The author names Baohua Shen (new First Author) and Minghai Li (new Corresponding Author) were added to the revised paper without explanation and without exceptional approval by the journal editor, which is contrary to the journal policy on changes to authorship. The editor reached out to the authors for an explanation, but they failed to provide a satisfactory explanation to these changes. In addition, it appears that Navid Bohlooli was claiming an affiliation with Sun-Life Company, Baku, Azerbaijan. When questioned, the author was unable to provide convincing evidence of the existence and nature of this company. Overall, the editor feels that the findings of the manuscript cannot be relied upon and that the article needs to be retracted. [ABSTRACT FROM AUTHOR]

Integrating a high power source, like a super capacitor (SCAP), and a lithium-ion battery (LIB) for electric vehicle (EV) applications yields achievement improvements, including maximum reliability, long lifetime (LT), small size, and competitive pricing for the overall source. A hybrid energy storage system (ESS) controlled by an intelligent energy management strategy (EMS) may be substantially included in multi-source EV design and development. Therefore, this paper proposes a hybrid chimp optimization algorithm (ChOA) and Levy walk technique to create an optimum EMS. The proposed technique reduces battery power (BP) stress and increases the LT, which is accomplished by using a hybrid ChOA-Levy walk (ChOA-LW) optimization algorithm with a rule-based approach in accordance with understanding the performance of LIB and SCAP. In order to optimize the rule-based EMS's control settings, the latter strategy is suggested. The control approach can be implemented online once the offline optimization procedure is finished. The presented technique is evaluated via simulation and on an experimental platform by means of a power emulator testbed of a LIB/SCAP hybrid ESS. In terms of BP stress and LT, the findings are compared with a conventional rule-based approach and a mono-source containing a regular high-power LIB. Results obtained demonstrate the effectiveness of the suggested technique, which enables the requested performance to be satisfied with better energy utilization. The assessment results also show notable LT improvements for the LIB, an improvement of up to 19% over the mono-source in reference to a conventional single cell LIB. • A hybrid ChOA and Levy walk technique to create an optimum energy management strategy. • Reduce battery power stress and increase the long lifetime of the battery. • Presenting an experimental platform by means of a power emulator testbed of a lithium-ion battery hybrid energy storage system. • An improvement of up to 19% over the mono-source in reference to a conventional single-cell lithium-ion battery. [ABSTRACT FROM AUTHOR]

This study contributes to the modeling and analysis of damping and vibration in the innovative composite sector and annular plates composed of a magnetorheological elastomer (MRE) reinforced with glass fibers. These plates are formed of laminate construction. For the purpose of this investigation, polar orthotropic laminas are used. The generalized Maxwell constitutive law is employed in order to describe the tunable viscoelastic properties of the MR elastomer, including storage and modal loss factor. The application of a magnetic field enables one to exert control over the storage and loss moduli of these materials. In addition, the effective mechanical properties of the MRE composite (MREC) are determined through a modified version of the Voigt micromechanical rule and the Halpin–Tsai rule. In order to define the displacement field of the plate, a hyperbolic higher-order shear deformation approach is used. By adopting Hamilton's principle, one may get the equations describing the motion as well as the relevant boundary and continuity conditions. In order to solve this system of highly coupled partial differential equations (PDEs), the 2D generalized differential quadrature (GDQ) approach is exploited. A comparison was made between the developed model and those available in the literature to validate the accuracy and convergence quality of the solution technique and formulation. A complete investigation is carried out into the influence of the magnetic field on the free-damped response of the MREC sector and annular plates. In addition, the effects of the composite and geometric properties of the structure on the natural frequencies and modal loss factors of the structure have been examined. • Free-damped vibrations of laminated annular and sector plates made of these materials are investigated. • Generalized Maxwell's constitutive model for viscoelastic MRECs is used. • 2-dimensional Chebyshev collocation method is applied. • Mode shape switching phenomenon is explored. [ABSTRACT FROM AUTHOR]

In this paper, the optimum operation of a distribution network in the presence of renewable resources, and a new combined system of liquid carbon dioxide energy storage is investigated. A comprehensive structure is proposed for modeling and optimizing the combination of wind turbine and solar sources with the new energy storage system by considering their converters. Then, a multipurpose structure in the presence of these resources and the new storage resource is presented to overcome the uncertainty of the output power of renewable resources and improve the reliability of the grid. To this end, first, by considering the probabilistic nature of wind and solar resources, a relatively comprehensive modeling of the system is presented. Economic costs, including the cost of setting up units, cost of generation, and emission of these units, are presented as optimization problem. The effects of the storage system on the load curve are investigated and discussed. The proposed objective function is determined based on optimal load distribution and technical constraints. The multi-objective group teaching optimization algorithm is used to solve the microgrid optimal operation problem. The proposed model considering three cases, is successfully implemented on a 33-bus RBTS distribution network. The results indicated that the total cost of the proposed system in the first, second, and third case is decreased by about 2.88%, 21.78% and 21.2% compared to the base case study. The cost reduction in the first case is due to the use of renewable energy sources, and this reduction in the second case is more due to the use of new storage. Finally, in the third case, due to the consideration of uncertainty and reliability index, compared to the second case, the amount of cost has increased slightly, but compared to the main case, there is a significant decrease, which indicates the superiority of the proposed model. [ABSTRACT FROM AUTHOR]

Ethanol production could be enhanced with ethanol removal in situ from the broth, during the experiments of ethanol fermentation coupled with pervaporation by mechanical vapor compression. The yeast cell could continuously grow for long time with cell density of 38 g/L obtained. The byproducts accumulation in the broth led to the culture deterioration of the fermentation and became the main inhibitor against the cell growth. The total flux of the polydimethylsiloxane (PDMS) membrane was in the range of 350 g/m 2 /h and 600 g/m 2 /h. At the downstream of the membrane, part of the permeate vapor under the vacuum condition before the inlet of the vacuum pump was condensed at the first condenser by the running water at the room temperature and the non-condensed vapor enriched with ethanol was compressed to the atmospheric pressure and pumped into the second condenser by the vacuum pump. The vapor in the second condenser was easily condensed into a liquid by air at room temperature since the pressure was increased. Ethanol concentration of over 50wt% could be obtained in the second condenser, which could greatly reduce the amount of the waste water treatment. Recovery of the permeate vapor heat would be achieved by the use of mechanical vapor compression heat pump, which could evidently save energy. [ABSTRACT FROM AUTHOR]

As the IEA reports indicated that nuclear power owns a growing market share, which means that nuclear power plants (NPPs) must be able to respond quickly to grid fluctuations. A good load-following capability is the basic requirement for the flexibility and safety of reactor operation. In order to study the load-following capacity of the molten salt reactor, this study took the liquid fuel molten salt reactor (MSR) as the research object. The system model and power control model were established with RELAP5/MOD4.0 program, which has been implanted with relevant physical properties of molten salt and calculation formula. The response characteristics of the control system under step load change, linear load change and typical daily load-following operation were simulated and analyzed. The results show that MSR has a good load-following capacity under the designed control logic, the core power can respond to the load variation quickly, the power overshoot and temperature overshoot are small, and the operating parameters of the reactor are under a reasonable operating range. The simulation analysis provides the reference for subsequent safety analysis and power control of molten salt reactor. • Inherent characteristics of self-stability and self-regulation of molten salt reactor were reflected. • The designed control strategy can meet the performance requirements of load-following. • The dynamic response of the system is good; the power overshoot and temperature overshoot are small. • The temperature change process is slow and the temperature variation is small during the entire process. [ABSTRACT FROM AUTHOR]

Abstract: We have examined solutions of a polystyrene-polybutadiene pentablock copolymer in n-heptane, a strongly selective solvent for polybutadiene. Small angle neutron scattering from 7 to 15% samples reveals domains about 10nm in radius formed by the association of ∼200 polystyrene blocks. Dynamic light scattering measurements on 8 and 9% samples showed three modes: a fast diffusive mode related to the collective diffusion in semidilute solutions/gels; a relaxational mode related to the local dynamics of polystyrene domains trapped in the gel formed by bridging the domains with the polybutadiene chains; and a very slow diffusive mode. The relaxational dynamics persisted over the entire temperature range, becoming faster with increasing temperature, indicating a decreased microviscosity at higher temperatures. The slow dynamics seems to be connected with heterogeneities in the physical gel due to microsyneresis and almost disappeared above 50°C. Macroscopic phase separation into two liquid phases was observed in a dilute solution of the un-associated copolymer, and into a liquid and gel phase at higher concentrations. The absence of flower-like micelles in dilute solutions and the macroscopic phase seperation suggest that the gels in the pentablock are formed by random association of multiplet domains and not by bridging of micellar domains. [Copyright &y& Elsevier]

A simple method for deposition of CdSe nanocrystals to silicon surfaces using self-assembled monolayers is described. CdSe nanocrystals were first synthesized by using sodium dioctyl sulfosuccinate as surfactant in inverse micellar solution. An obvious 1s–1s absorption peak at 527 nm and narrow width of photoluminescence peak at 552 nm implied a narrow size distribution of CdSe nanocrystals. Then these nanocrystals were assembled on SiO2-coated Si substrate by bifunctional linker molecule (3-mercaptopropyl)-trimethoxysilane (MPS). Auger electron spectroscopy showed that the MPS monolayer has been limited on SiO2-coated Si substrate. The results of atomic force microscopy analysis and contact-angle measurements confirmed that nanocrystals with uniform sizes were bound to MPS-modified substrate through Cd–S covalent bounding. [Copyright &y& Elsevier]

Improved process separation factor and heat integration are two key issues to increase the energy efficiency of ethanol production in a pervaporation membrane bioreactor (PVMBR). A PVMBR with permeate fractional condensation and mechanical vapor compression was developed for energy efficient ethanol production. A condensation model based on the mass balance and thermodynamic equilibrium in the partial vacuum condenser was developed for predicting the purification performance of the permeate vapor. Three runs of ethanol fermentation-pervaporation experiment were carried out and ethanol concentration of higher than 50 wt% could be achieved in the final condensate, with the separation factor of the process for ethanol increased to 20. Ethanol production could be enhanced in the bioreactor and 17.1 MJ of the energy could be produced in per liter of fermentation broth, owing to 27.0 MJ/kg heating value of the recovered ethanol. Compared with the traditional pervaporation process with low temperature condensation for ethanol production, 50% of the energy would be saved in the process. The energy consumption would be further reduced, if the available energy of the permeate vapor was utilized by integrating the mechanical vapor compression heat pump. [ABSTRACT FROM AUTHOR]

An energy efficient pervaporation membrane bioreactor with mechanical vapor compression was developed for ethanol recovery during the process of fermentation coupled with pervaporation. Part of the permeate vapor at the membrane downstream under the vacuum condition was condensed by running water at the first condenser and the non-condensed vapor enriched with ethanol was compressed to the atmospheric pressure and pumped into the second condenser, where the vapor was easily condensed into a liquid by air. Three runs of fermentation–pervaporation experiment have been carried out lasting for 192 h, 264 h and 360 h respectively. Complete vapor recovery validated the novel pervaporation membrane bioreactor. The total flux of the polydimethylsiloxane (PDMS) membrane was in the range of 350 g m −2 h −1 and 600 g m −2 h −1 . Compared with the traditional cold traps condensation, mechanical vapor compression behaved a dominant energy saving feature. [ABSTRACT FROM AUTHOR]

Abstract Mixing system of uranium pebbles and thorium pebbles is compared with thorium blanket system to utilize thorium in Pebble Bed Fluoride Salt-cooled High Temperature Reactor (PB-FHR). A random modeling method is introduced to simulate the pebble mixing system. Cases with different volume fractions of uranium pebbles are researched to find the optimal utilization of uranium and the lower power nonuniformity. It indicates that using thorium in pebble mixing system with 80 vol% uranium pebbles can improve uranium utilization by 10%, while in thorium blanket system it can be increased by 20%. The radial power peak factor in pebble mixing system is about 1.48 while in thorium blanket system is about 1.83. In-pile residence time of thorium pebbles in pebble mixing system is only 4.7 year, while in thorium blanket system is 9 year. Thorium utilization with pebble mixing system in PB-FHR shows a little lower fuel utilization but higher safety and technical feasibility. Highlights • Pseudorandom distribution models of different pebbles are successfully established. • We find the optimal utilization of uranium under 80 vol% uranium pebble. • The radial power peak factor and in-pile residence time of thorium pebble significantly decrease in pebble mixing system. [ABSTRACT FROM AUTHOR]

• Changes in metabolomic and transcriptomic networks of mango endosperm mutants. • Effects on flavor components and synthesis pathways of esters in the mango fruit. • Revealed genes specific accumulation of carotenoid biosynthetic pathway in mango. Targeted transcriptomic and metabonomic analyses were conducted to explore the metabolic basis of amino acids, organic acids, terpenoids, esters and carotenoids in two genotypes of mango cultivars 'Guifei,' an endospermic genotype and a mutant genotype without an endosperm that produce large- and small-sized fruit, respectively, with different flavor metabolite contents. A total of 88 different metabolites were separately identified in the pulp of different-sized mango fruit, including organic acids, amino acids, phenolic acids and saccharides. Seventy-three types of volatile organic compounds (VOCs) were identified in the pulp of different-sized mango fruit based on metabolomics. The major volatile compounds identified were terpenoids, esters and aromatics. p-Mentha-1(7),2‑dien-8-ol, Selina-6-en-4-ol and 1,3-Dimethyl-5-(propen-1-yl) adamantane are major terpenes that play an important role in the aroma of 'Guifei' mango fruits. In addition, p-Mentha-1(7), 2‑dien-8-ol was found in the mutant genotype without endosperm for the first time and had a relatively high concentration in the glycosidically bound form in 'Guifei' mango. Twelve types of carotenes were identified in the pulp of different-sized mango fruits. The carotenoid contents of the two genotypes were significantly different, and β-cryptoxanthin and zeaxanthin were the key metabolites that caused the difference in the total carotenoid content between the examined cultivars. The integrated analysis of carotenoid metabolism data and transcriptome data showed that GGPS, Z-ISO and NCED were the key genes that led to the differences in fruit flavor and carotenoid content of the mango pulp. This study provides new insights into the effects of mutant genotypes on the appearance and intrinsic quality of fruit. [ABSTRACT FROM AUTHOR]

Thorium blanket fuel is investigated in Pebble Bed Fluoride salt-cooled High temperature Reactor (PB-FHR) with 19.9 at% 235 U seed fuel to improve the utilization of uranium fuel. Uranium fuel utilization is optimized with lots of parameters, such as graphite-to-thorium atom ratio (C/Th), graphite-to-uranium atom ratio (C/U), discharge burnup of thorium and uranium, and the dimension of the seed/blanket region. It is found that the equivalent discharge burnup, defined as total released energy over the mass of uranium, could be improved to around 265 MWd/kgU, which is 20% higher than discharge burnup using pure uranium fuel. In equilibrium state, the temperature reactivity coefficients of fuel and coolant are both negative. Other properties such as radial power peak factor, life of reflector, in-pile residence time of thorium pebble and radioactive waste are analyzed. Finally, baseline design parameters are recommended for further thermal-hydraulic analysis and TRISO fuel performance. [ABSTRACT FROM AUTHOR]

• As micronized sand, Copper tailing modifies the particle gradation in concrete. • Copper tailing improves workability, long-term strength and durability of concrete. • Copper tailing promoted homogeneity, microstructure and pore structure of concrete. Preparing concrete with the copper tailing as micronized sand to modify manufactured sand (MS) contributes to both the utilization of copper tailing and improvement on the concrete performance. In this paper, experiments on preparing concrete with copper tailing as micronized sand were investigated. Parallel investigations on the properties, such as compressive strength, elastic modulus, chloride permeability coefficient, dry shrinkage and pore structure as well as heavy metal leachability test of concretes prepared with MS, RS, MR and MC were conducted. The results show that the gradation of MS is optimized by replacing it with 20% copper tailing. MC concrete has better anti-segregation ability and long-term strength development. It is found that MC increases elastic modulus and chloride permeation resistance of concrete, however, the dry shrinkage ratio of MC concrete is the higher than other groups. The ITZ between aggregates and paste of MC concrete become tighter. Although the porosity of concrete is increased in MC concrete, its pore size distribution is refined. Finally, the heavy metal leaching of copper tailing was significantly reduced when copper tailing was immobilized in MC concrete, which could eliminate the environmental impacts from copper tailing. [ABSTRACT FROM AUTHOR]