• Journal of environmental and Sanitary engineering
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• v.16 no.1
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• pp.72-90
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• 2001

This study was conducted to evaluate desorption efficiencies accuracy and precision by $CS_2$ and thermal desorption method for polar and non-polar organic solvents collected on activated carbon(AC), activated carbon fiber(ACF), carbosieve SIII, materials tested were Methyl alcohol, n-Hexane, Benzene, Trichloroethylene, Methyl isobutyl ketone and methyl cellosolve acetate and six different concentration levels of samples were made. The results were as follows ; 1. Accuracy on kind adsorbent and desorption method was low. In case of $CS_2$ desorption solvent, Overall B and Overall CV on AC and ACF were 43% and 6.63%, respectively. In case of thermal desorption method, accuracy of thermal desorption method appeared higher than solvent desorption method by AC 18.0%, 3.54%, ACF 2.6%, 2.57%, Carbosieve SIII 13.7% and 1.97%, respectively. 2. In the concentration level III, accuracy of thermal desorption method on adsorbent was in order as follow ; ACF > Carbosieve SIII > AC in the methyl alcohol and Carbosieve SIII > ACF > AC in the rest of them all subject material and Concentration levels showed good precision at EPA recommend standard (${\leq}{\;}30%$) 3. DEs by type of organic solvent adsorbent and desorption method are as follows ; In the case that desorption solvent is $CS_2$, DE of Methyl alcohol is AC 47.5%, DE of all materials is ACF about 50%. In the case of thermal desorption method, DE of Methyl alcohol is AC 82.0%, ACF 97.4%, Carbosieve SIII 86.3%. DE of the later case is prominently improved more than one of former. In particular, Except that DE of EGMEA is ACF 88.5%, DE of the rest of it is more than 95% which is recommend standard MDHS 72. With the result of this study, in order to measure various organic solvent occurring from the working environment, in the case of thermal desorption method, we can get the accurate exposure assessment, reduce the cost, and use ACF as thermal desorption sorbent which available with easy.

• Wind and Structures
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• v.23 no.6
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• pp.505-521
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• 2016

The objective of this study is to investigate numerically the effect of building roof shaps on wind flow and pollutant dispersion in a street canyon with one row of trees of pore volume, $P_{vol}=96%$. A three-dimensional computational fluid dynamics (CFD) model is used to evaluate air flow and pollutant dispersion within an urban street canyon using Reynolds-averaged Navier-Stokes (RANS) equations and the Explicit Algebraic Reynolds Stress Models (EARSM) based on k-${\varepsilon}$ turbulence model to close the equation system. The numerical model is performed with ANSYS-CFX code. Vehicle emissions were simulated as double line sources along the street. The numerical model was validated by the wind tunnel experiment results. Having established this, the wind flow and pollutant dispersion in urban street canyons (with six roof shapes buildings) are simulated. The numerical simulation results agree reasonably with the wind tunnel data. The results obtained in this work, indicate that the flow in 3D domain is more complicated; this complexity is increased with the presence of trees and variability of the roof shapes. The results also indicated that the largest pollutant concentration level for two walls (leeward and windward wall) is observed with the upwind wedge-shaped roof. But the smallest pollutant concentration level is observed with the dome roof-shaped.

• Journal of Plant Biotechnology
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• v.7 no.3
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• pp.161-167
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• 2005

Brassinosteroids are steroidal plant hormones and are known to modulate physiological and cellular response in a wide range of plant species. Considerable insights has been achieved of the physiological role of brassinosteroid in Brassica species in the past few years, but their effect on direct organogenesis has not been extensively studied. In this sense, under optimal basal media and growth conditions we tested the cellular and organogenic response of 24-epibrassinolide (EBL) in a variable concentration (0.1 to $5.0\;{\mu}M$) and Zeatin (Z) (1.0 to $100\;{\mu}M$) and their synergic effect on hypocotyl explants of cauliflower and broccoli. The isolated EBL accelerated cell elongation and promotes direct organogenesis. One micromolar EBL + $10\;{\mu}M$ of Z was the most efficient combination for cell elongation, cell differentiation as well as for organogenesis. A suppressing effect on root induction was confirmed for all the tested hormone levels. The general results indicate a synergic effect of EBL-Z and EBL potentates Zeatin activity, at least in certain tissues. Besides de genetic factors, we can speculate that the natural hormone concentration in the explants might affect the responses by application of exogenous growth regulators. Experiments with new plant growth regulators, like brassinolide, are important aiming to maximize or accelerate plant regeneration for in vitro multiplication or for genetic transformation.

• Nutrition Research and Practice
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• v.15 no.2
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• pp.187-202
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• 2021

BACKGROUND/OBJECTIVES: The exposure to sucrose in rats has mimic abnormalities attributed to metabolic syndrome (MetS). The effects of honey bee and "free" glucose and fructose, have not been explored in this context. The aim was to expose Wistar rodents to sucrose solution (SS), honey solution (HS) and fructose/glucose solution (GFS) at 30% to assess their effects. SUBJECTS/METHODS: HS (n = 10), SS (n = 10) and GFS (n = 10) groups were formed. Solutions were ad libitum along 14-weeks. RESULTS: Between solutions consumptions, honey was significantly 42% higher (P = 0.000), while similar consumption was observed among GFS and SS. The feeding pattern of HS consumption was irregular along experiment; while the food intake pattern showed the similar trend among groups along time. Non statistical differences were obtained in any biochemical and anthropometric measure, however, a higher concentration of leptin (721 ± 507 pg/mL), lower concentration of total cholesterol (TC; 48.87 ± 2.41 mg/100 mL), very low density lipoprotein (VLDL; 16.47 ± 6.55 mg/100 mL) and triglycerides (82.37 ± 32.77 mg/100 mL) was obtained in SS group. For anthropometric values, HS showed less total adipose tissue (AT; average 26 vs. 31-33 g) and adiposity index (average 6.11 vs. 7.6). Due to sugar-sweetened beverages consumption increases the risk for the development of chronic diseases; correlations between fluid intake and anthropometric and biochemical parameters were assessed. A moderate correlation was obtained in groups with the weight of total AT and solution intake; for the weight gain in GFS group and for triglycerides in HS and GFS. The highest hepatic tissue damage was observed in SS group with multiple intracytoplasmic vacuoles, atypia changes, moderate pleomorphism and hepatocellular necrosis. CONCLUSIONS: In spite of the significantly higher consumption of HS, biochemical, anthropometrical and histological effects were not remarkably different in comparision to other sweeteners.

• Advances in nano research
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• v.1 no.4
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• pp.193-202
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• 2013

In this article, we present the effects of Ag doping and after-growth thermal annealing on the photoluminescence (PL) and thermoluminescence (TL) behaviors of $SnO_2$ nanoparticles. $SnO_2$ nanoparticles of 4-7 nm size range containing different Ag contents were synthesized by hydrothermal process. It has been observed that the after-growth thermal annealing process enhances the crystallite size and stabilizes the TL emissions of $SnO_2$ nanostructures. Incorporated Ag probably occupies the interstitial sites of the $SnO_2$ lattice, affecting drastically their emission behaviors on thermal annealing. Both the TL response and dose-linearity of the $SnO_2$ nanoparticles improve on 1.0% Ag doping, and subsequent thermal annealing. However, a higher Ag content causes the formation of Ag clusters, reducing both the TL and PL responses of the nanoparticles.

• Journal of Microbiology and Biotechnology
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• v.14 no.2
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• pp.426-429
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• 2004

Eleven fungal strains previously isolated from the Mexican desert were evaluated for their capacity to use catechin as carbon source in submerged cultures. At 2 g/l of catechin, all strains grew better than the control strains, Aspergillus niger Aa-20. Aspergillus niger PSH and Penicillium commune EH2 degraded 79.33％ and 76.35％ with degradation rates of 0.0065 and 0.0074 g/l/h, respectively, when an initial catechin concentration of 3 g/l was used. Obtained results demonstrated the potential biotechnological capacity of these fungal strains to use condensed tannins as carbon source.

• Journal of Microbiology and Biotechnology
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• v.32 no.1
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• pp.64-71
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• 2022

The discarding of wastes into the environment is a significant problem for many communities. Still, food waste can be used for lactic acid bacteria (LAB) growth. Here, we evaluated three growth media equivalent to de Mann Rogosa Sharpe (MRS), using apple bagasse, yeast waste, fish flour, forage oats, and cheese whey. Cell-free supernatants of eight LAB strains were tested for antimicrobial activity against nine indicator microorganisms. The supernatants were also evaluated for protein content, reducing sugars, pH, and lactic acid concentration. Cell-free supernatants from fish flour broth (FFB) LAB growth were the most effective. The strain Leuconostoc mesenteroides PIM5 presented the best activity in all media. L. mesenteroides CAL14 completely inhibited L. monocytogenes and strongly inhibited Bacillus cereus (91.1%). The strain L. mesenteroides PIM5 consumed more proteins (77.42%) and reducing sugars (56.08%) in FFB than in MRS broth (51.78% and 30.58%, respectively). Culture media formulated with agroindustrial wastes positively improved the antimicrobial activity of selected LAB, probably due to the production of antimicrobial peptides or bacteriocins.

• Journal of Environmental Health Sciences
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• v.15 no.2
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• pp.41-49
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• 1989

The assay on microbial dehydrogenase activity by using TTC was investigated. The experimental results are summarized as follows: 1. The TF production was affected by dissolved oxygen. Dissolved oxygen in samples could be effectively removed by adding $Na_{2}SO_{3}$ as reductant prior to incubation. 2. The toxic effect on TF formation was observed at up to 0.1% of final TTC concentration when VSS concentration was 2.7g/l. As the VSS concentration increased the effect decreased. 3. It was clearly revealed that the TF generation rate decreased with increasing VSS concentration. The dilution of sludge could be applicable when VSS level is below 3.5g/l. 4. The TF production of endogenous phase (De) could be used as a measure for the viable fraction of sludge over various sludge ages. The additional TF production (Ds) due to extracellular substrate responded to De, not to VSS concentration.

• Advances in nano research
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• v.3 no.2
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• pp.81-96
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• 2015

Octahedral shaped single crystalline undoped and Ga-doped indium oxide nano-and microcrystals were fabricated using vapor-solid growth process. Effects of Ga doping on the crystallinity, defect structure, and optical properties of the nano-/microstructures have been studied using scanning electron microscopy, microRaman spectroscopy, transmission electron microscopy and cathodoluminescence spectroscopy. It has been observed that incorporation of Ga does not affect the morphology of $In_2O_3$ structures due to its smaller ionic radius, and similar oxidation state as that of In. However, incorporation of Ga in high concentration (~3.31 atom %) causes lattice compression, reduces optical band gap and defect induced CL emissions of $In_2O_3$ nano-/microcrystals. The single crystalline Ga-doped, $In_2O_3$ nano-/microcrystals with low defect contents are promising for optoelectronic applications.

• Korean Chemical Engineering Research
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• v.61 no.1
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• pp.97-108
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• 2023

Two carbonaceous adsorbents CAT and CARBOPAL were tested for reducing the concentration of the three herbicides in water: 2,4-D (2,4-dichlorophenoxyacetic acid), TCP (2,4,6-trichlorophenol) and metolachlor. Textural and chemical characterization of the adsorbents include nitrogen isotherms, FTIR, titration and thermogravimetric analyses. Adsorption was studied in discontinuous adsorption experiments at different pH values. The experimental adsorption isotherms data were fitted to four theoretical models. Adsorbent characterization reveals that CAT has higher micropore area, lower pore diameter and lower acidity than CARBOPAL. The adsorption is a second-order process and the isotherms best fitted to Sips model. The efficiency of the process depends mainly on the charge of the adsorbate for TCP and 2,4-D, but it depends on the charge of the surface for metolachlor. Adsorption capacity is higher on CAT for 2,4-D and TCP (small molecules), and it is higher on CARBOPAL for metolachlor (large molecules). Theoretical calculations clearly support this assumption.