In this work, the electrochemical oxidation on boron-doped diamond of synthetic wastes polluted with surfactant sodium dodecylbenzenesulfonate (SDBS) has been studied. Results show that SDBS can be ...successfully removed with this technology inside different current densities and concentration ranges. The oxidation of the SDBS seems to occur in two main sequential steps: the first is the rapid degradation of SDBS, and the final is the less efficient oxidation of aliphatic intermediates to carbon dioxide. The nature of supporting electrolyte (NaCl, Na
2SO
4 and K
3PO
4) influences on the efficiency of the electrochemical oxidation process. The treatment of the NaCl solution seems to be more efficient in the chemical oxygen demand (COD) removal, while the sulphate and specially the phosphate media improve the TOC removal. However, in spite of this observation, chemical oxidation of SDBS by different types of oxidants cannot explain alone the results of the electrochemical oxidation with diamond anodes. This suggests that the synergistic effect of the different oxidation mechanisms that occurs into the electrochemical cell (direct oxidation and mediated oxidation by hydroxyl radicals and by oxidants formed from the electrolyte) is the responsible of the great efficiencies obtained with this technology in the treatment of organics.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UL, UM, UPCLJ, UPUK
► Central Beam Column (CBC) structure is introduced in a staged construction of a large underground. ► Settlement control over an underground Metro station in Tehran is investigated using 3D FE ...analysis. ► Cases of system with, without CBC and of an improved ground by consolidation grouting are compared. ► CBC is a reliable and effective way in controlling settlement and stress concentration in supports. ►CBC as a controlled and permanent structure, is more reliable and durable support in its life time.
The ground surface settlement caused by underground excavation is an important matter in urban development. The settlement control of large span underground station in Tehran Metro is investigated using a full three-dimensional (3-D) finite element analysis. A method of underground construction by increasing the rigidity of the supporting system using Central Beam Column (CBC) structure is introduced. In construction of large underground space, effect of presence of CBC structure is compared to a case without CBC structure. The CBC structure increases the rigidity of supports and decrease the stress concentration and displacement in supporting system. It generally decreases the soil deformation above the underground space resulting in smaller ground surface settlement.
Influence of spacing of central columns and their dimensions on the magnitude of settlement are also investigated in this study. Effect of ground improvement of Tehran soil by consolidation grouting on ground surface settlement and stress distribution in supporting system is modeled and analyzed. It can be concluded that in an urban area over a large underground spaces (e.g., underground metro stations) with relatively low overburden similar to northern Tehran, CBC structure can be very effective and reliable measure in controlling and reducing the surface settlement and the stress concentration on initial supporting system.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UL, UM, UPCLJ, UPUK
Depression is a mental disorder that highly associated with immune system. Therefore, this study compares the serum concentrations of IL-21, IL-17, and transforming growth factor β (TGF-β) between ...patients with major depressive disorder and healthy controls.
Blood samples were collected from 41 patients with major depressive disorder and 40 healthy age-matched controls with no history of malignancies or autoimmune disorders. The subjects were interviewed face to face according to DSM-IV diagnostic criteria. Depression score was measured using completed Beck Depression Inventory in both groups. The serum concentrations of IL-21, IL-17, and TGF-β were assessed using ELISA.
The mean score of Beck Depression score in the patient and control groups was 35.4±5.5 and 11.1±2.3. IL-17 serum concentrations in the patients and the control group were 10.03±0.6 and 7.6±0.6 pg/mL, respectively (P=0.0002). TGF-β level in the patients group was significantly higher than compare to the control group; 336.7±20.19 vs. 174.8±27.20 pg/mL, (P<0.0001). However, the level of IL-21 was not statistically different between the two groups 84.30±4.57 vs. 84.12±4.15 pg/mL (P>0.05).
Considering pro-inflammatory cytokines, current results support the association of inflammatory response and depressive disorder. So, it seems that pro-inflammatory factors profile can be used as indicator in following of depression progress and its treatment impacts.
Today, research on healthcare logistics is an important challenge in developing and developed countries, especially when a pandemic such as COVID-19 occurs. The responses required during such a ...pandemic would benefit from an efficiently designed model for robust and sustainable healthcare logistics. In this study, we focus on home healthcare logistics and services for planning the routing and scheduling of caregivers to visit patients’ homes. Due to the need for social distancing during the COVID-19 pandemic, these services are highly applicable for reducing the growth of the epidemic. In addition to this challenge, home healthcare logistics and services must be redesigned to meet the standards of a triple bottom line approach based on sustainable development goals. A triple bottom line approach finds a balance between economic, environmental, and social criteria for making a sustainable decision. Although, recently, the concept of green home healthcare has been studied based on the total cost and green emissions of home healthcare logistics and services, as far as we know, no research has been conducted on the formulation of a triple bottom line approach for home healthcare logistics and services. To achieve social justice for caregivers, the goal of balancing working time is to find a balance between unemployment time and overtime. Another contribution of this research is to develop a scenario-based robust optimization approach to address the uncertainty of home healthcare logistics and services and to assist with making robust decisions for home healthcare planning. Since our multi-objective optimization model for sustainable and robust home healthcare logistics and services is more complex than other studies, the last novel contribution of this research is to establish an efficient heuristic algorithm based on the Lagrangian relaxation theory. An initial solution is found by defining three heuristic algorithms. Our heuristic algorithms use a symmetric pattern for allocating patients to pharmacies and planning the routing of caregivers. Then, a combination of the epsilon constraint method and the Lagrangian relaxation theory is proposed to generate high-quality Pareto-based solutions in a reasonable time period. Finally, an extensive analysis is done to show that our multi-objective optimization model and proposed heuristic algorithm are efficient and practical, as well as some sensitivities are studied to provide some managerial insights for achieving sustainable and robust home healthcare services in practice.
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IZUM, KILJ, NUK, PILJ, PNG, SAZU, UL, UM, UPUK
Abstract A split-plot experiment was conducted in a randomized complete block design with three replications in two cropping years at Mazandaran Rice Research Institute to study cultivation and ...irrigation regimes. The main factor is three-level irrigation regimes, permanent irrigation throughout the day (T1), irrigation two days after water disappears from the soil (T2) and permanent soil saturation (T3) the second factor is three-level cultivation methods., Plowless cultivation (W1), stack 60 cm (W2), and stack 80 cm (W3). Based on the results obtained from the combined analysis, the effect of the year was significant in terms of rainfall, productivity 2, number of tillers, number of empty grains, 1000-grain weight, percentage of the crushed grain, and white rice yield. The effect of the main factor was significant for all traits except productivity 1 and plant height. Based on the results of comparing the mean effect of year × treatment, four treatments, without plowing with permanent irrigation throughout the day in the first and second year of the experiment, cultivation without plowing with irrigation two days after water disappears from the soil in the second year of experiment and cultivation without Plowing with permanent saturated irrigation in the first and second years of the experiment was identified in terms of grain yield as suitable planting methods with appropriate irrigation regimes. Based on the results obtained from the polygon view in different years of the experiment, T3W1, T3W2, and T1W1 treatments can be suggested as desirable treatments in terms of irrigation regimes and cultivation methods in this rice cultivar. According to the ranking diagram of treatments based on traits in the years of experimentation, T1W1, T2W2 and T1W3 were introduced as the most desirable treatments for cultivating this rice cultivar.
Resumo Um experimento de parcelas subdivididas foi conduzido em um delineamento de blocos completos casualizados com três repetições em dois anos de cultivo no Mazandaran Rice Research Institute para estudar os regimes de cultivo e irrigação. O principal fator são os regimes de irrigação em três níveis, irrigação permanente ao longo do dia (T1), irrigação dois dias após o desaparecimento da água do solo (T2) e saturação permanente do solo (T3); o segundo fator são os métodos de cultivo em três níveis: cultivo sem arado (W1), empilhar 60 cm (W2) e empilhar 80 cm (W3). Com base nos resultados obtidos na análise combinada, o efeito do ano foi significativo em termos de precipitação pluviométrica, produtividade 2, número de perfilhos, número de grãos vazios, peso de 1.000 grãos, porcentagem de grãos triturados e rendimento de arroz branco. O efeito do fator principal foi significativo para todas as características, exceto produtividade 1 e altura de planta. Com base nos resultados da comparação do efeito médio ano x tratamento, quatro tratamentos, sem aração com irrigação permanente ao longo do dia no primeiro e segundo ano do experimento, cultivo sem aração com irrigação dois dias após o desaparecimento da água do solo no segundo ano de experimento e cultivo sem aração com irrigação saturada permanente no primeiro e segundo ano do experimento, foi identificado em termos de produtividade de grãos como métodos de plantio adequados com regimes de irrigação adequados. Com base nos resultados obtidos na visão poligonal em diferentes anos do experimento, os tratamentos T3W1, T3W2 e T1W1 podem ser sugeridos como tratamentos desejáveis em termos de regimes de irrigação e métodos de cultivo nessa cultivar de arroz. De acordo com o diagrama de classificação dos tratamentos baseados em características nos anos de experimentação, T1W1, T2W2 e T1W3 foram introduzidos como os tratamentos mais desejáveis para o cultivo dessa cultivar de arroz.
The aim of this survey was to investigate the main reasons for extraction of permanent teeth, and its correlation with age, gender, education level, smoking habits, and time of last dental visit, ...family income, and professions in Kabul, Afghanistan.
The study proposal was approved by Research Ethics Committee of Khatam AL Nabieen and was conducted over a period of 5 months; its population consisted 594 patients, aged 10-70 years, who underwent extraction. The frequency distribution was calculated using X
test, ANOVA and
-test for differences in mean number of patients.
A total of 594 patients underwent extraction. The highest rate (53.8%) of extraction occurred for those 21-40 years old. Females compromised 51.3% of patients. Two hundred (33.6%) patients were uneducated. Tooth loss due to caries was 30.1%; patient-request was 18.3%; impacted teeth was 14.4%. Other causes were periodontal reasons, failed root canal therapy (RCT), Tooth mobility, and Root fractures.
The result of this survey indicated that caries, patient request, and impaction were the leading reasons for tooth extraction. The majority of patients were uneducated, and had insufficient family income. Most of the patients were housewives and laborers.
In the present study, cellulose acetate/graphene oxide (CA/GO) composite nanofibers were prepared via the electrospinning method to remove Cr(VI) ions from aqueous solution via adsorption process in ...a batch mode. The impact of adsorption parameters, including contact time, pH, Cr(VI) concentration, and temperature was investigated to obtain the optimum conditions for the uptake of maximum Cr(VI) ions from water within a short time. The kinetic data of Cr(VI) adsorption were well fitted by pseudo-first-order and pseudo-second-order kinetic models, whereas Redlich-Peterson, Langmuir and Freundlich, isotherm models were used to describe the equilibrium data of Cr(VI) adsorption by the CA/GO nanofibers. The effect of temperature on the adsorption capacity of Cr(VI) ions using the nanofibers indicated that the higher temperatures were favorable for higher adsorption of Cr(VI) ions using the nanofibers. The thermodynamic parameters results indicated the spontaneous and endothermic of Cr(VI) sorption nature using the CA/GO nanofibrous adsorbent. The maximum monolayer adsorption capacity of nanofibers toward Cr(VI) ions sorption was 422.3 mgg
−1
which was comparable with other adsorbents. The reusability of composite nanofibers was carried out for five adsorption–desorption cycles. The obtained results exhibited the high capability of CA/GO nanofibrous adsorbents for Cr(VI) ions sorption from actual wastewater.
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DOBA, EMUNI, FIS, FZAB, GEOZS, GIS, IJS, IMTLJ, IZUM, KILJ, KISLJ, MFDPS, NLZOH, NUK, OILJ, PILJ, PNG, SAZU, SBCE, SBJE, SBMB, SBNM, SIK, UILJ, UKNU, UL, UM, UPUK, VKSCE, ZAGLJ
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•Effects of induced healing process on fracture properties were studied.•Different fracture criteria were considered to quantify induced healing efficacy.•Induced healing indices at ...different heating-healing cycles were calculated.•Extension of fatigue life under induced healing was evaluated.•Correlation between crack properties under induced healing was evaluated.
This research presents effects of induced heating-healing process on fracture properties and life extension of asphalt mixtures. Induced heating-healing technique is an innovative technique to repair damages and heal cracks in asphalt mixtures, implementing an external electromagnetic field to raise temperature of asphalt mixture. Temperature rising results in melting and flowing of asphalt binder between crack edges, healing cracks, and recovering internal strength of asphalt mixture lost during service life. Previous researchers considered different criteria to quantify induced healing efficiency in asphalt concrete, resulting in substantial differences. Nevertheless, conclusions presented by previous researchers are not comparable due to different materials, heating, healing, and testing conditions. Hence, a further study is needed to identify induced healing effectiveness based on asphalt mixtures form different binder grades. In this study, activated carbon modified and unmodified asphalt binders were utilized to prepare asphalt mixtures. Then, a cyclic heating-healing scenario under semi-circular bending (SCB) test was conducted at intermediate and low temperatures. Values of the fracture criteria (i.e., peak load, stress intensity factor, stiffness, strain energy, critical strain energy release rate, and fracture energy) were quantified at each cycle. Besides, extensions of fatigue and thermal fatigue lives obtained via induced healing process were characterized. Comparing results of modified and unmodified mixtures indicates that activated carbon significantly improves efficacy of induced healing. Additionally, induced healing process leads to different effects on different crack features. Moreover, induced healing efficiencies obtained based on fatigue and thermal fatigue extensions are approximately similar to that of peak load criterion. This study indicates that to evaluate effects of induced heating-healing process on improvement of different mechanical behaviors in asphalt mixtures over service life, corresponding crack property (criteria) needs to be considered.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
There are many novel applications of space-time decoupled least squares and Galerkin formulations that simulate wave propagation through different types of media. Numerical simulation of stress wave ...propagation through viscoelastic medium is commonly carried out using the space-time decoupled Galerkin weak form in site response problem, etc. In a recent investigation into accuracy of this formulation in simulating elastic wave propagation, it was shown that the diffusive and dispersive errors are greatly reduced when space-time coupled least squares formulation is used instead in variational form. This paper investigates convergence characteristics of both formulations. To this end, two test cases, which are site response and impact models for viscoelastic medium, are employed, one dominated by dispersive and the other by diffusive numerical error. Convergence studies reveal that, compared to the commonly used space-time decoupled Galerkin and the coupled least squares formulation has much lower numerical errors, higher rates of convergence, and ability to take far larger time increments in the evolution process. In solving such models, coefficient matrices would require updating after each time step, a process that can be very costly. However large time steps allowed by cLs are expected to be a significant feature in reducing the overall computational cost.
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FZAB, GIS, IJS, KILJ, NLZOH, NUK, OILJ, SBCE, SBMB, UL, UM, UPUK
This paper deals with the analysis of free vibration and biaxial buckling of double-magneto-electro-elastic nanoplate-systems (DMEENPS) subjected to initial external electric and magnetic potentials, ...using nonlocal plate theory. It is supposed that the two nanoplates are bonded with each other using a visco-Pasternak medium, and are also limited to the external elastic substrate. Hamilton's variational principle is applied to acquire the partial differential equations of motion and corresponding boundary conditions for three modes (out-of-phase, in-phase and one nanoplate fixed) and solved analytically to determine clear closed-form phrase for complex natural frequencies natural frequencies and buckling loads. Numerical examples are performed to demonstrate the changes of the vibration frequency and buckling load ratio (NLL) of DMEENP against to different values of the nonlocal parameters, initial external electric and magnetic potentials, aspect ratio, damping and transverse stiffness coefficients of the viscoelastic foundation, shear stiffness coefficient of Pasternak medium, length to thickness ratio, nanoplate thickness and higher modes. Also, the effect of biaxial compression ratio on the buckling load is investigated. Results of this study show that considering the interaction between two Magneto-electro-elastic nanoplates lead to achieving greater frequencies and biaxial buckling loads. Moreover, the influences of the nonlocal parameter become more pronounced when the half wave number, initial external electric potential and aspect ratio increase, while the effect of the length to thickness ratio and initial external magnetic potential has the opposite trend.
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•The effects of various parameters on the frequencies and buckling load ratio are discussed.•The frequency and buckling load ratio decreased by increasing the external electric potential.•The frequency and buckling load ratio increased by increasing the external magnetic potential.•The vibration frequency significantly decreases by increasing damping coefficient.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UL, UM, UPCLJ, UPUK, ZRSKP
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