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Numerical modeling of free-surface flow over a mobile bed with predominantly bedload sediment transport can be done by solving the shallow water and Exner equations using coupled and splitting approaches. The coupled method uses a coupling of the governing equations at the same time step leading to a non-conservative solution. The splitting method solves the Exner and the shallow water equations in a separate manner, and is only capable of modeling weak free-surface and bedload interactions. In the current study, an extended version of a Godunov-type wave propagation algorithm is presented for modeling of morphodynamic systems using both coupled and splitting approaches. In the introduced coupled method the entire morphodynamic system is solved in the form of a conservation law. For the splitting technique, a new wave Riemann decomposition is defined which enables the scheme to be utilized for mild and strong interactions. To consider the bedload sediment discharge within the Exner equation, the Smart and Meyer-Peter & Muller formulae are used. It was found that the coupled solution gives accurate predictions for all investigated flow regimes including propagation over a dry-state using a Courant-Friedrichs-Lewy (CFL) number equal to 0.6. Furthermore, the splitting method was able to model all flow regimes with a lower CFL number of 0.3.

In this study, two treatment steps were performed to completely remove p-nitroaniline (PNA). In the first stage, the catalytic ozonation process (COP) using the synthesized nanoparticles of magnesium–aluminum layered double hydroxide (MgAl-LDH) was applied for pre-treatment. Effective parameters in the COP, including initial pH, initial PNA concentration, catalyst dose, and contact time has been investigated. Response Surface Method)RSM(was applied to optimize process conditions in the COP. The effluent from the COP entered the sequencing batch moving bed biofilm reactor (SBMBBR). The optimum conditions for the COP process were initial PNA concentration: 120 mg/L, pH: 8.25, LDH dose: 750 mg/L, and reaction time: 70 min. Under these conditions, the maximum removal efficiency of PNA, COD, and TOC was about 91.5, 83, and 70%, respectively. The biological reactor was operated under conditions of hydraulic retention time (HRT) of 24 h, pH of 6.5–7, mixed liquor suspended solids attached to bio-carriers (MLSSatt.) of 4700 mg/L, mixed liquor volatile suspended solids attached to bio-carriers (MLVSSatt.) of 3200 mg/L, MLSS of 1000 mg/L, and MLVSS of 880 mg/L. In this study, using the COP/SBMBBR system, the complete PNA analysis and maximum removal efficiency of COD and TOC were about 99 and 97%, respectively.

Context: The fatigue is reported as the most common and annoying symptom in patients with cancer, timely diagnosis, and treatment can significantly influence the treatment and rehabilitation. It is crucial to have an appropriate tool to accurately assess fatigue status. Objectives: Our purpose was to assess psychometric properties of the Persian versions of fatigue scale by Original Scales from the viewpoint of children with cancer (Child Fatigue Scale [CFS]-24 h), their parents (Parent Fatigue Scale [PFS]-24 h), and staff (Staff Fatigue Scale FSF-24 h). Methods: Convenience sampling of the participants was conducted 100, including children with cancer within the age range of 7–12 years, their parents, and caregivers in medical staff. Test–retest reliability and internal consistency were evaluated using intraclass correlation (ICC) and Cronbach's alpha coefficient. Dimensionality was determined by factor analysis. The patients' fatigue was also assessed through visual analog scale-fatigue (VAS-F). Results: Test–retest (ICCCFS = 0.71, ICCPSF = 0.82, and ICCSFS = 0.78) was acceptable with a high level of internal consistency (αCFS = 0.80, αPFS = 0.83, and αSFS = 0.84). Factor analysis identified three, five, and two components for the CFS, PFS, and Staff Fatigue Scale (SFS), respectively. There was moderate correlation between CFS and VAS-F. Conclusions: Results of the current study indicated that CFS in children with cancer, PFS in their parents, and SFS in medical staff were valid and reliable instruments to assess fatigue from the viewpoint of children with cancer along with their parents and medical staff.

In this paper, the structured parameters effect on nonlinear optical properties of CdS/ZnS quantum dot (QD) is studied. The self-consistently solved Schrodinger–Poisson equations obtains the QDs energy eigen values and functions. Then, size effect of QDs on energy levels of the ground and first excited states, matrix element and third-order nonlinear susceptibilities related to intersubband transitions are investigated using the density matrix method. The proposed structure results the large dipole transition and high nonlinear and tunable susceptibilities that are very suitable for implementation of active and passive devices and systems. It has been observed that the structure parameters QDs can manage the amplitude and resonance frequency of the nonlinear third-order susceptibilities.

Dimethyl Ether Waterflooding (DEW) is a promising water-soluble solvent-based EOR technique. Here, we study DEW mechanisms by developing a mathematical model taking into account the swelling and viscosity reduction of oil. Our analyses show that the swelling and viscosity reduction of oil cannot explain the observed increased recovery of DEW in the published core flooding data. Therefore, we define the residual oil saturation as a linear function of DME concentration in the oil phase to fit the model to the experimental data. After model validation against a 1D core flooding experiment, we utilize the model to study the effect of permeability heterogeneity and the injected DME slug size on the recovery of oil from a water-flooded chalk reservoir. We observe a sharp increase in the ultimate recovery when the DME slug size increases from 0.2 to 1.8 pore volume with a DME concentration of 10 wt%. Since DME is an expensive agent, the optimal slug size requires an integrated economic evaluation. We calculate the increased Net Present Value (NPV) of DEW flooding in the heterogeneous chalk reservoirs compared to the conventional water flooding for two scenarios of well completions. By comparing the water breakthrough and DME induced recovery, we conclude that the most economical scenario for the DEW flooding is observed in the reservoirs with the lowest heterogeneity.

Separation of hydrogen gas from the outlet of water-gas shift reactor via palladium membrane was simulated with a two-dimensional computational fluid dynamic model. To study the influence of the geometry of membrane on the separation of hydrogen, four various membrane modules with cylindrical shells and cone tubes were considered. The results showed that the conical membrane module with upper and bottom diameters of 2 mm and 16 mm can potentially have the highest average flux across the other studied cases. To investigate the effect of flow pattern, four various flow patterns were applied to the model and it was found that the counter-current flow pattern has the highest flux across the membrane for the case in which the cross section is reduced along with the length of the membrane. The results also indicated that the change in the cross section of the membrane module can prevent the intensification of the concentration polarization index within the membrane.

Hydrogen storage capacity (HSC) of multilayer graphitic carbon nitride, d-g-C3N4 (d is interlayer spacing), and its palladium nanocomposite, d-Pd@g-C3N4, were investigated using multiscale computational techniques including quantum mechanics calculations and grand canonical Monte Carlo (GCMC) simulation. According to the results, the volumetric HSC of 8-g-C3N4 and 8-Pd@g-C3N4 can reach to DOE target of 30 gH2/L at 177 K, 5.7 MPa, and 177 K, 4.0 MPa, respectively. The gravimetric HSC of 10-g-C3N4 and 12-Pd@g-C3N4 meet the DOE target of 4.5 wt% at 150 K, 3.5 MPa, and 125 K, 4.0 MPa, respectively. The incorporation of Pd atoms enhances the delivery volumetric HSC of 6-, 8-, 10-, and 12-g-C3N4 by 49, 55, 129, and 146%, respectively at 177 K and 0.5 MPa. On the other hand, the incorporation of Pd atoms has a negative effect on the delivery gravimetric HSC of 6- and 8-g-C3N4 and positive effect for 10- and 12-g-C3N4. The estimated isostric heat, Qst, of adsorption is 5.5–8.5 kJ/mol. The maximum value of Qst for both nanoadsorbents belong to those with d = 8 A. The structure of adsorbates and possibility of multilayer adsorption occurrence were also investigated using pair correlation functions and density profiles.

The aim of this research was to investigate the removal efficiency of ciprofloxacin (CPX) from aqueous solutions by a novel semi-fluid Fe/charcoal micro-electrolysis reactor and process optimization using response surface methodology (RSM). Effective factors in the removal process including CPX initial concentration, pH, amount of Fe/charcoal, aeration amount and contact time were investigated. The total organic carbon (TOC) removal was determined under optimum conditions of the reactor. The maximum removal efficiency of 95.5% was obtained in optimal conditions as follow; initial concentration of CPX: 17.27 mg/L, pH: 5.38, Fe/charcoal mass: 22.70 g/300 mL, aeration rate: 4.33 L/min and contact time: 105.36 min. The quadratic equation was obtained with a high degree of fit. TOC concentration in optimal conditions decreased from 16 mg/L to 4 mg/L. As a result of this, the Fe/charcoal semi-fluidized micro-electrolysis reactor has a high efficiency in removing drug compounds such as CPX from aqueous solutions.

The direct insertion of niobium(V) and zirconium (IV) into the ordered cubic pores of Ia3d mesoporous silica, KIT-6, was performed by employing a hydrothermal method and utilizing a versatile structure directing agent, Pluronic P123 triblock copolymer, in n-butanol as co-solvent. The effect of simultaneous incorporation of niobium and zirconium on the acidity of KIT-6 nanomaterial was investigated and compared to Nb-KIT-6 and Zr-KIT-6. The prepared mesoporous Nb Zr/KIT-6 was characterized by N2 porosimetry, TEM, FESEM, XRD, NH3-TPD, FT-IR, and ICP-OES. Results displayed that niobium and zirconium ions were well incorporated into the KIT-6 framework and the entire ordered pore structure has been retained. Incorporation of niobium and zirconium ions enhanced the catalytic activity of KIT-6 as strong acid sites. Eventually, the synthesized Nb Zr/KIT-6 was used as an effective, recyclable and green catalyst for the multi-component, one-pot production of some substituted benzylpyrazolyl coumarins via condensation of phenylhydrazine, ethyl acetoacetate, 4-hydroxycoumarin and various aldehydes under mild solvent-free conditions with fair to excellent yields.

4-Nitroaniline (4-NA) is one of the common pollutants in wastewater. Because of the toxicity, carcinogenicity and mutagenicity, it has been reported as priority pollutants. The purpose of this study was to synthesize ZnO nanoparticles and its immobilization on the surface of stones to study the removal efficiency of 4-NA by the hybrid advanced oxidation process (UV/ZnO/O3). The SEM, TEM and XRD analyzes were used to investigate the physiochemical properties of nanoparticles. The effective parameters on the process including the initial pH of the solution, contact time, dose of immobilized nanoparticles, the initial concentration of 4-NA, were investigated. The kinetics of the degradation reactions were determined. Data analysis was performed using SPSS-16 software. By increasing the catalyst dose from 1 g/L to 3 g/L, the removal efficiency increased from 75% to 92%. The highest 4-NA removal efficiency of 96% was achieved by hybrid advanced oxidation process (UV/ZnO/O3) in optimal conditions including pH: 5–7, the dose of immobilized ZnO: 3 g/L, the initial concentration of 4-NA: 10 mg/L and contact time: 60 min. Therefore, this process is recommended for the removal of resistant and toxic pollutants from aqueous solutions with a relatively high efficiency.

Microbial desalination cell (MDC) is an environmentally friendly technology and a new method for desalination. The aim of this research is to investigate the extent of removal of arsenic (As) from aqueous solutions by MDC. To examine the efficiency of the process, synthetic As were prepared with concentrations of 100–600 μg/L in deionized water. The removal efficiency was examined at retention times of 30–120 min, at psychrophilic, mesophilic, and thermophilic temperatures and dissolved oxygen of 2–6 mg/L. The real water sample of Bardsir region in Kerman as well as the synthetic wastewater sample was experimented with to examine removal efficiency under the optimal conditions. The optimal conditions for removal of As were obtained as 600 mg/L of As, 6 mg/L of dissolved oxygen, temperature of 25–30 °C, and retention time of 120 min. Under these conditions, As removal efficiency in the synthetic samples of As, real water sample of Bardsir region, and synthetic wastewater sample was obtained as 75, 68, and 56%, respectively. Considering the relatively high efficiency of MDC in removal of As and its advantages including being environmentally friendly and saving energy, it is an effective method in removal of As from aqueous solutions.

This study aims at the mathematical optimization by Box-Behnken statistical design, fabrication by ionic gelation technique and in vitro characterization of insulin nanoparticles containing thiolated N- dimethyl ethyl chitosan (DMEC-Cys) conjugate. Then Optimized insulin nanoparticles were loaded into the buccal film, and in-vitro drug release from films was investigated, and diffusion coefficient was predicted. The optimized nanoparticles were shown to have mean particle size diameter of 148nm, zeta potential of 15.5mV, PdI of 0.26 and AE of 97.56%. Cell viability after incubation with optimized nanoparticles and films were assessed using an MTT biochemical assay. In vitro release study, FTIR and cytotoxicity also indicated that nanoparticles made of this thiolated polymer are suitable candidates for oral insulin delivery.

In this paper, the extended finite element method is implemented to model a cracked finite domain in which the surface is subjected to a non-Fourier thermal shock. The dynamic fully coupled thermoelasticity equations based on Lord-Shulman theory are considered. The interaction integral is used to extract the stress intensity factors as well as the implicit version of the Newmark scheme as the time integration method to solve semidiscrete governing equations. The effect of relaxation time on the temperature distribution and stress intensity factors under thermal shock is investigated. Furthermore, secondary heat conduction near the tip of an inclined crack due to the reflection of the thermal wave from its surface and consequently local deviation in temperature and displacement fields is discussed in detail. The propagation of a curved crack under thermal shock is reported, as well.

In this paper, the extended finite element method is implemented to extract stress intensity factors (SIFs) for a stationary crack in an isotropic 2D finite domain under thermal shock. The fully coupled generalized thermoelasticity theory based on Green-Lindsay (G-L) model is considered. The interaction integral is developed to compute the stress intensity factors in which the dissipated part of the strain energy density is accounted to preserve domain-independency of. The Newmark time integration scheme is used to solve semidiscrete governing equations. According to the results, the speed of stress and temperature waves controls the time variations of stress intensity factors especially at early times of the thermal shock.

There are ideas that urban agriculture could assist in creating sustainable cities. However, little information is available on its financial benefits. Integrating Value Engineering (VE), Risk Management (RM) and Multi-Criteria Decision-Making (MCDM) techniques in this research improved the design and economical aspects of a city park based on urban agricultural development. This research was carried out on a part of Chehelbazeh Park in Mashhad, Iran. The base plan was designed based on conventional park design approach, and the proposed agricultural plan was designed by applying urban agricultural approach. In this study, based on the cost-benefit value index, the index of the base conventional plan was 0.86, which is considered uneconomic, and that of the proposed agricultural plan was 4.08. According to the results of this study, using urban agriculture in city landscapes can have high profitability and low risks. In general, VE, RM, and MCDM techniques can be used collectively as valuable tools in the design and maintenance of urban parks to achieve sustainability while making efficient use of the budget. The methodology of this study provides a decision-making framework for urban landscapes and can help policymakers, urban planners, and researchers on planning or designing urban parks in other countries. Also, it makes it easier for urban landscape managers and decision-makers to understand the importance of using fruit trees, vegetables, and other productive plants in urban landscaping.