In today's business environments, the high importance of economic benefits and environmental impacts of using scrapped products has caused most companies to move to designing the closed loop supply ...chain network. This paper considers the closed loop supply chain network design problem under hybrid uncertainty, while there are two sources of uncertainty for most parameters, thus require fortifying of the robustness of the decision. The first source is that some uncertain parameters may be based on the future scenarios which are considered according to the probability of their occurrence. The second source is that the values of these parameters in each scenario are usually imprecise and can be specified by possibilistic distributions. In this case, the best robust decision has some additional properties in terms of mean value and variability of the objective function. We introduced two types of the variability named scenario variability and possibilistic variability. Possibility theory is used to choose a solution in such a problem and a novel robust fuzzy stochastic programming approach is proposed that has significant advantages. The performance of the proposed model is also compared with that of other models in term of the mean cost and variability by simulation.
Many studies have been conducted on hospital solid waste management (HSWM) throughout the world, especially developing countries. This interdisciplinary study aims to summarize the available ...knowledge on the health and environmental risks of hospital solid waste (HSW) and also, develop a dynamic associational assessment among hospital solid waste generation rate (HSWGR), hospital solid waste composition (HSWC), gross domestic product (GDP) per capita, and environmental performance index (EPI) in some developing countries for the first time. The results of this study showed that researchers from India, China, Pakistan, Brazil, and Iran had found more evidence about the health, economic, and environmental issues in HSW than the other developing countries. The literature showed that the highest and lowest reported HSWGR (in national average level) belonged to Ethiopia (6.03) and India (0.24) kg bed −1 day−1, respectively. It has also been shown that all studied countries except Serbia, have higher levels of hazardous waste in their HSWC, based on the WHO's standard. Furthermore, the quantity and quality of HSW in developing countries depend on the service provided by the hospital, type of hospital, HSWM system, and the level of regional economic and culture. The association analysis showed that the EPI and GDP per capita of developing countries were significantly (p-value <0.05) associated with HSWGR, non-hazardous HSW, and hazardous HSW by the Spearman coefficients equal to 0.389, 0.118, −0.118, and 0.122, 0.216, and −0.346, respectively. However, it can be concluded that GDP per capita and EPI have a weak correlation with hazardous HSW and non-hazardous HSW. Moreover, HSW has many hazardous health and environmental risks such as dioxin and furan, that must be controlled and managed through implementing programs and policies based on sustainable development. As a final point, we believed that the present study can be considered to be a guide for future studies on HSWM in developing countries.
•Hospital waste is one of the most threating issue for health and the environment.•Developing countries are more vulnerable to hospital waste threats.•The main elements of hospital waste management in developing countries are reviewed.•The main threats of hospital waste management in developing countries are highlighted.
The cotton‐derived nanoalkalinecellulose (NAC) flocculated on the Fe3O4‐nanoparticles was analytically characterized as Fe3O4@NAC. With the 1:5.7 weight ratio for organic:inorganic and the ...base‐capacity equal to 7.5 mmol HO−/g, the Fe3O4@NAC represented a catalytic advantage in the room‐temperature one‐pot pseudo‐multicomponent synthesis of tetra‐hydrodipyrazolopyridines (THDPPs) in water. Mechanistic monitoring supported no requisite to acid/base catalyst in the first phase for rapid formation of intermediate 3‐methylpyrazolone (A) by Knorr reaction of the ethylacetoacetate with hydrazine hydrate in water at room temperature. Alternatively, Fe3O4@NAC showed catalytic roles in the further reaction phases in synthesis of THDPPs from the A. Excellent base capacity, hydrogen‐bonding performance, and stability due to no significant activity loss and leaching after five reaction cycles are advantages of this organometallic catalyst.
The cotton‐derived nanoalkalinecellulose (NAC) immobilized on the Fe3O4 nanoparticles was analyzed as the Fe3O4@NAC core–shell. With the base capacity ~ 7.5 mmol HO−/g, Fe3O4@NAC represented a catalytic superiority in two dissimilar pseudo‐multicomponent (p‐MC) synthesis of tetra‐hydrodipyrazolopyridines (THDPPs) in water at room temperature. While mechanistic studies revealed no need of any catalyst for the first reaction phase to Knorr synthesis of 3‐methyl‐pyrazolone, Fe3O4@NAC catalyzed further phases of p‐MC synthesis of THDPPs from the 3‐methyl‐pyrazolone. No leaching of this organometallic catalyst was confirmed.
We created AA2024–AA1050 and AA2024–AA1050/0.005 vol.% Al
2
O
3
nanocomposites by six accumulative roll bonding (ARB) process cycles. We used AA2024 and AA1050 sheets with a thickness of 0.7 mm and ...plate-shaped alumina nanoparticles to create a composite. The two AA1050 and one AA2024 sheets (among the two AA1050 sheets) were ARB-ed up to six cycles with and without adding alumina nanoparticles. Also, a sample of the AA1050 without composite making was ARB-ed up to six cycles. We aged some composites after the ARB process in the furnace at 110, 150, and 190 °C. This project performed SEM, TEM, and EDS-MAP analyses, tensile strength, microhardness, and Pin-on-Disc tests to study the ARB-ed sheets. The results of the tensile tests showed that the tensile strength of AA2024–AA1050 created by the six cycles ARB process was two times more than primary AA1050. Also, the wear resistance of this composite was 74% more than six cycles ARB-ed the AA1050. Using 0.005 vol.% alumina nanoparticles in AA2024–AA1050 composite improved its wear resistance by 30%. In the following, the aging process caused an improvement in tensile strength and total elongation of AA2024–AA1050/Al
2
O
3
nanocomposites.
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•MNPs@C mesoporous composite was prepared, characterized and its adsorptive/catalytic performance was assessed.•Dye removal efficiency of adsorption Fenton, UV-Fenton and sono-Fenton ...processes was compared.•The removal efficiency was in accordance to the following order: UV-Fenton>US-Fenton>Fenton>adsorption.•MNPs@C shows high adsorption capacity, high reusability and stability and low iron leaching.
Textile wastewater was treated using an enhanced simultaneous adsorption/oxidation process with magnetic nanoparticles-functionalized carbon (MNPs@C) and H2O2, UV and ultrasonic (US). Both film- and pore-diffusion affect adsorption mechanisms were included in the adsorption process. The dye adsorption was enhanced by oxidative degradation in the present of H2O2 with the suitability in order of UV-Fenton>US-Fenton>Fenton. Catalytic potential of 47% was observed for MNPs@C/H2O2/UV system. For UV-Fenton system 94.8% removal of dye with minimal iron leaching was observed after 5 times of recycle. Increasing catalytic activity of MNPs@C on direct red 16 (DR16) degradation follows the order of PMS>PS>H2O2.
The present study aimed to model and optimize the dimethyl phthalate (DMP) degradation from aqueous solution using UV
C
/ Na
2
S
2
O
8
/Fe
2+
system based on the response surface methodology (RSM). A ...high removal efficiency (97%) and TOC reduction (64.2%) were obtained under optimum conditions i.e. contact time = 90 min, SPS concentration = 0.601 mM/L, Fe
2+
= 0.075 mM/L, pH = 11 and DMP concentration = 5 mg/L. Quenching experiments confirmed that sulfate radicals were predominant radical species for DMP degradation. The effect of CO
3
−
on DMP degradation was more complicated than other aquatic background anions. The possible pathway for DMP decomposition was proposed according to HPLC and GC–MS analysis. The average oxidation state (AOS) and carbon oxidation state (COS) values as biodegradability indicators demonstrated that the UV
C
/SPS/Fe
2+
system can improve the bioavailability of DMP over the time. Finally, the performance of UV
C
/SPS/Fe
2+
system for DMP treatment in different aquatic solutions: tap water, surface runoff, treated and raw wastewater were found to be 95.7, 88.5, 80.5, and 56.4%, respectively.
Graphical abstract
Case I: (a) In mild climate condition, traffic loading causes initiation and propagation of micro-cracks in asphalt concrete. (b) These distresses can be partially healed under the microwave heating ...imposed by external electromagnetic radiation that is referred to as microwave healing. Case II: (c) In extreme climate condition (e.g., rainy, snowy and cold), moisture and freeze-thaw damages cause asphalt binder to become stiff, loss of adhesion between asphalt binder and aggregate particles and loss of cohesion within asphalt binder. The combination of these factors with traffic loading results in extended micro-cracks and damages in asphalt concrete. (d) These damages can be partially healed through microwave heating/healing process with less efficiency, in comparison with Case I.
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•The effects of moisture and freeze-thaw damages on microwave heating/healing process were examined.•Cyclic fracture-healing scenario was conducted to impose mechanical damage.•The concurrent effects of mechanical, moisture and freeze-thaw damages were investigated.•The moisture and freeze-thaw damages decreased microwave healing efficiency.•The freeze-thaw damages have shown the highest adverse effects on microwave healing process.
Microwave heating/healing is a kind of maintenance technique to repair micro-cracks in asphalt mixes. This method was conducted mostly on unaged materials, and the effects of moisture and freeze-thaw damages have not completely been studied. The fluidity of the asphalt binder, accomplished by heating, increases the ability of binder to fill micro-cracks and heal the asphalt mixes. Moisture and freeze-thaw damage increase the modulus of asphalt binder resulting decrease of fluidity of material. In contrast, moisture and freeze-thaw damages could reduce the ability of mixes to heal. In this research, mixes were prepared using neat and activated carbon modified asphalt binders. In order to assess the microwave heating properties, mixes were subjected to different levels of moisture and freeze-thaw conditions. The microwave heating performance was investigated under electromagnetic radiation. It was found that activated carbon is a proper binder-based additive that increases electromagnetic absorption of asphalt mixes. Indirect Tensile (IDT) and Semi-Circular Bending (SCB) specimens were fabricated, and different levels of moisture and freeze-thaw cycles were applied. For quantification of microwave healing capability of damaged asphalt concrete mixes, the cyclic fracture-healing tests were conducted on IDT and SCB specimens. Individual and combined effects of mechanical damage, fracture temperature, notch length, moisture, and freeze-thaw cycles on microwave healing performance of asphalt concrete mixes were investigated. Results showed that moisture and freeze-thaw damages have adverse effects on microwave healing performance of asphalt concrete mixes. Increased critical factors caused further detrimental effects on microwave healing performance of mixes.
The plasma membrane of eukaryotic cells is commonly believed to contain ordered lipid domains. The interest in understanding the origin of such domains has led to extensive studies on the phase ...behavior of mixed lipid systems. Three-component phase diagrams, composed of a high melting temperature (Tm) lipid, cholesterol, and a low Tm lipid have been valuable in studying lipid phase behavior. However, developing phase diagrams over the entire composition space and with precise tie-lines requires significant experimental effort. In this study, a machine learning approach was used to predict the Tm of lipids and generate phase diagrams from lipid mixtures. First, artificial neural network (ANN) was used for the prediction of Tm. The network was trained using available Tm data and was able to generate Tm values that closely matched literature results for its testing dataset. This model was then used to predict the Tm for lipids that have not yet been experimentally tested. Then, random forests (RF) and support vector machines (SVM) were trained and tested for their ability to predict a test three-component phase diagram. The model from the RF algorithm was able to generate a diagram that closely matched published results. This model was then used to generate phase diagrams for lipid mixtures at various temperatures and various degrees of unsaturation. This machine learning approach to the generation of lipid phase diagrams has the potential to save significant time and resources in studies of lipid phase behavior.
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•Machine learning approaches can be used to predict lipid phase behavior.•An artificial neural network accurately predicted lipid transition temperatures.•A random forest model predicted 3-component phase diagrams of lipid mixtures.•Predicted phase diagrams closely matched published results.•Effect of changes in temperature and lipid chemistry on phase diagrams is studied.
The optimization of distributed generation technologies and storage systems are essential for a reliable, cost-effective, and secure system due to the uncertainties of Renewable Energy Sources (RESs) ...and load demand. In this study, two algorithms, the Multi-Objective Particle Swarm Optimization (MOPSO) and the Non-Dominant Sorting Genetic Algorithm II (NSGA-II) were utilized to design five different case studies (CSs) (photovoltaic (PV)/wind turbine (WT)/battery/diesel generator (DG), PV/WT/battery/fuel cell (FC)/electrolyzer (EL)/hydrogen tank (HT), PV/WT/battery/grid-connected, PV/WT/battery/grid-connected with Demand Response Program (DRP), and PV/WT/battery/electric vehicle (EV)) to minimize life cycle cost (LCC), loss of power supply probability (LPSP), and CO2 emissions. In fact, different backups are provided for (PV/WT/battery), which is considered as the base system. Further, the uncertainties in RES and load were modeled by the Taguchi method, and Monte Carlo simulation (MCS) was used to model the uncertainties in EV to achieve accurate results. In addition, in CS4, a Demand Response Program (DRP) based on Time-of-Use (TOU) price is considered to study the effect on the number of specific components and other parameters. Finally, the simulation results verify that the NSGA-II calculation provides accurate and reliable outcomes compared to the MOPSO method, and the PV/WT/battery/EV combination is the most suitable option among the five designed scenarios.
•Proposing optimal size and comparison of diverse backups for PV/WT/battery system.•Using MOPSO and NSGA-II optimization algorithms considering TOU DRP.•Modeling the uncertainty of EV parameters using the MCS approach.•Modeling the uncertainty of renewable units and loads using the Taguchi method.•Modeling the optimization problem using the LCC, LPSP, and CO2 emissions indices.
In this work, nanoporous WO3 was formed by anodization in oxalic acid. Various oxalic acid concentrations (0.01–0.4 M) and anodization times (1–240 min) on the formation of nanoporous WO3 were ...investigated. Uniform nanoporous WO3 with pore diameter size of 70 nm and pore wall thickness of 19 nm was produced by using 0.05 M oxalic acid and 120 min anodization time. Meanwhile, a partially porous structure or film dissolution occurred on the samples prepared using other oxalic acid concentrations and anodization times. In addition to the nanoporous layer, a compact layer embedded with nanobubbles was formed underneath the nanoporous layer. The as-anodized nanoporous film was amorphous and it transformed to monoclinic WO3 after annealing in argon (Ar) and nitrogen (N2) gases. N was doped into WO3 after annealing in N2 and it suppressed the grain growth. The N-doped WO3 which possesses thinner pore wall showed higher electrochromic current density value than the film annealed in Ar.
•Uniform nanoporous WO3 was formed by anodization in 0.05 M oxalic acid for 120 min.•A compact layer embedded with nanobubbles was formed underneath nanoporous layer.•N was doped into WO3 after annealing in N2 and it suppressed the grain growth.•N-doped WO3 showed higher electrochromic current density than film annealed in Ar.
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