13 research outputs found

    Perturbation method for linear and non-linear fractional order systems and integral representation for evaluation of integrals

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    In the present work, the authors used the Laplace transform - perturbation method to solve certain linear and non-linear systems of fractional differential and difference equations with constant coefficients with the fractional derivatives in the Caputo sense. We also considered the problems of string vibrations in different cases with fractional damping. Another purpose of this article is to evaluate certain integrals. Illustrative examples are also provided

    Evaluation of the Capability of Carbon Dioxide Greenhouse Gas Absorption Using Nano Bio-Activated Carbon of Crataegus Sanguinea Core

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    BACKGROUND AND OBJECTIVE: Considerable increase in carbon dioxide gas in the Earth's atmosphere has caused several problems such as increasing the temperature of the earth, droughts and sudden changes in the climate. The purpose of this study was to evaluate the capability of carbon dioxide as greenhouse gas absorption using activated nanobiocarbon from the Crataegus Sanguinea core. METHODS: In this experimental study, the carbon dioxide gas penetration time in three subgroups with pressure (5,10,15 bars), flow (5,10,15 ml/min) and temperatures (20,30,60 °C) at concentrations of 0 to 1 gr / ml through a carbon dioxide gas capsule in a fixed bed column filled with 2 g of adsorbent synthesized by a carbon dioxide gas sensor. The synthesized nano-biocarbon adsorbent from the Crataegus Sanguinea Core was pyrolysed at a temperature of 300 ° C and activated at 600 °C. The research data were examined with pseudo -first-order and pseudo-second-order models. FINDINGS: Significant increase in gas infiltration time was observed at 15 bars pressure (86.71±0.09 min, p0.98 on empirical data from absorption. CONCLUSION: The results of the study showed that increasing pressure and decreasing temperature and flow increase the time of carbon dioxide penetration onto synthesized adsorbent

    Pathogen monitoring in indoor systems of tilapia aquaculture in Bafq, Iran

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    In recent years, aquatic diseases have damaged aquaculture industry in different areas of the world. Although tilapias are known as resistant fish against different pathogens, but there are some reports about infectious diseases of tilapia. Tilapia aquaculture in Iran is in the beginning stage. So, planning for hygiene observations and preventing of disease prevalence must be considered. Tilapia hatchery and indoor systems of National Research Center of Saline water Aquatics were monitored for infectious disease from October 2012 to February 2014. Unusual locomotion/feeding or uncommon signs in the shape or body surface of cultured tilapias, fries and eggs or exceed mortalities were mentioned for bacterial, fungal, parasitic or viral pathogens. Infectious agents in this study were bacteria Streptococcus and Edwardsiella, the fungi Penicillium and Aspergillus and parasitic monogeneans Gyrodactylus and Dactylogyrus. No viral agent was diagnosed. Although recorded pathogens were rarely observed during the study but much attention must be paid for hygiene monitoring and instruction performance

    Study on macrobenthic communities in the range of fish cage-culture area (before breeding) in the southern Caspian Sea (Mazandaran coast-Kelarabad)

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    The abundance and biomass of benthic macroinvertebrates were studied in the place of fish cage culture in southern coasts of Caspian sea (Mazandaran waters- kelarabad). The goal of this study was to consider of fish cage culture effects on the abundance and biomass of benthic macroinvertebrates. The sampling was carried out in 3 stations in depth of 20 meter of Kelarabad waters monthly. In this study 7 species were identified belonged to 5 genus of 4 family. Totally 23442 sample of benthic invertebrates were counted that the lowest and highest abundance were in station 1(23.4%) and station 2(46.8%) respectively. The results of stations study showed that the highest abundance and biomass were in stations 2 and 3 with the average of 646 ± 1230.4 n/m^2 and 0.526 ± 1.001 gr/m^2 respectively. This coulld be respectively dependant to not settling of cage (witness station) and appearance of Cerastoderma glaucum because of its large body in station 1. The difference of abundance and biomass between different stations was not significant (p ›0.05). The study on abundance and biomass in different seasons showed that the highest abundance in autumn with the avarage of 888.13 ± 1371.58 n/m^2 belonged to Strblospio gynobranchiata and the highest biomass belonged to C. glaucum which was because of appearance of not native species of polychaeta and also the species with shell covering from bivalvia. The results showed that the specie of S. gynobranchiata from polychaeta including 93.3% of abundance was the dominant specie that could be related to appropriate ecological conditions for living and high adaptability. It was concluded that the abundance and biomass of benthic macroinvertebrates in station 1 was lower than other stations which was related to fish cage culture activity and its effects on benthic macroinvertebrates. So it is suggested that each mariculture activity in southern coasts of Caspian Sea should be carried out with regarding to environmental considerations and performance of comparative evaluation project of environmental effects

    Study on physic-chemical parameters of waters for fish cage culture site selection in the southern of Caspian Sea

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    Marine aquacultures growth require good quality water is leading to high efficiency and low risk to human health. In other words, the water quality is a critical factor to success and failure of the aquaculture industry. The aim of this project is to study water quality and the trophic status at the different depths and layers in the southern Caspian Sea based on environmental parameters and nutrients during three periods (2008, 2009 and 2010-2011) in order the feasibility of fish cage. Results showed that water temperature, transparency, pH, dissolved oxygen were varied 5.50-32.60 ̊C, 3.50- 10.00 m, 7.15-8.80 and 3.18-12.00 mg/l at the different depths and layers, respectively. In addition, The values of NH4^+, NH3, NO^2-, NO3^- and PO4^-3 were 0.001-0.140 mg/l, 0.01-22.63 µg/l, 0.1-21.2 µg/l, 0.001-0.423 mg/l and 0.008-0.071 mg/l, respectively. Inorganic nitrogen (DIN/N), inorganic phosphorous (DIP/P) and total phosphorous (TP) were registerd 0.68-14.75, 0.07-0.68 and 0.01-2.67 µM, respectively. Thermal startification are more important for fish-breeding. Thermal stratification was occurred from depths greater than 20 m in late spring to early fall in the Caspian Sea. Optimum transparency for fish farming cage was considered less than 5 meter which in this study were recorded from 20 to 50 meter depths. The range of the standard of pH and dissolved oxygen for fish farming cage were 7.80-8.50 and >5 mg /l that in current study results of pH and dissolved oxygen were consistent.Various forms of nitrogen (ammonium, nitrite and nitrate ) at the different layers were acceptable and less than the threshold limit of Australia and New Zealand. But, phosphate value was more than threshold limit of Australia and New Zealand at some layers depth during years of 2009 and 2010- 2011. The results of the nutrients compared with data from the reference year (1996-1996 ) in the Caspian Sea was shown that this ecosystem passed oligotrophic status and shifted to mezotrophic and eutrophic condition. In addition, the values of NH4/N, NO3/N and DIP/P compared with eutrophic condition of reference year (2005) showed that Caspian ecosystem was not passed euotrophic condition and it still under mezotrophic status. As a conclusion, it seems that offshore of the Caspian Sea (depths between 20 to 50 meter) were suitable for different species of fish for cage culture. But, since 2000 decayds the Caspian Sea has experienced four times algal bloom (toxic and harmful species) and in recent years a number of other species also has reached to bloom potential and also mezotrophic condition of this ecosystem, it is appropriate that the establishment of fish farming cages carried out as a pilot to more precautionary approach which not lead to environmental disaster

    Integral transform method for solving time fractional systems and fractional heat equation

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    In the present paper, time fractional partial differential equation is considered, where the fractional derivative is defined in the Caputo sense. Laplace transform method has been applied to obtain an exact solution. The authors solved certain homogeneous and nonhomogeneous time fractional heat equations using integral transform. Transform method is a powerful tool for solving fractional singular Integro - differential equations and PDEs. The result reveals that the transform method is very convenient and effective

    Radiographic Findings and Serological Tests for Diagnosis of Helicobacter Pylori Infection in Dyspeptic Patients

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    Abstract Background & aim: With different methods for diagnosing H. pylori infections the aim of this study was to compare barium swallows radiographic findings and serological tests for diagnosis of Helicobacter pylori infection in dyspeptic patients. Methods: In this analytic cross-sectional study, 60 patients with documented gastric or duodenal ulcer, referring to Yasuj Shahid Mofateh Clinic No.2 were randomly selected. For all patients, Serologic testing determining the Helicobacter pylori infection was performed using specific IgG antibody titer. Afterward, barium swallow radiograph was performed on all patients. The results of the diagnostic procedure was evaluated by the indices of sensitivity, specificity, positive predictive value, negative predictive value, the percentage of false positives, the percentage of false negative and true accuracy with 95% confidence interval were analyzed. Results: From a total of 60 serological testing, 37 patients (61.6 %) had positive and 23 (39.4 percent) had negative results. Barium swallows radiography of 7 out of 60 patients (11.7 percent) was positive. Among patients with positive serology, 5 patients had positive and 2 patients had negative results. Barium swallows sensitivity and specificity of serological tests was estimated 13.5 and 91 percent respectively. Conclusion: According to the high specificity percent, barium swallow radiography method can be considered as a confirmatory method in the diagnosis of H. pylori infection. Key words: Helicobacter pylori, serology, barium swallow, specificity, sensitivit
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