33 research outputs found
Thin film nanocomposite membranes of PIM-1 and graphene oxide/ZIF-8 nanohybrids for organophilic pervaporation
In this work, thin film nanocomposite (TFN) membranes of super-glassy polymer PIM-1 containing zeolitic imidazolate framework-8 (ZIF-8)/graphene oxide (GO) composites (ZG) have been prepared by dip-coating onto water pre-impregnated polyvinylidene fluoride (PVDF) substrates. Higher flux and improved separation factors as compared to bare PIM-1 thin film composite (TFC) membranes have been achieved in organophilic pervaporation; for an aqueous feed solution with 5 wt% of butanol at 65 °C, a total permeate flux of 7.9 ± 0.69 kg m-2h-1 and a separation factor (ßBtOH/H2O) of 29.9 ± 1.99 have been obtained with a TFC membrane containing 0.5 wt% of ZG filler. The pervaporation separation index (PSI) of this membrane (228 kg m-2h-1) is amongst the highest values reported in the literature. This excellent performance is attributed to the formation of a defect-free PIM-1 active layer (<1 µm) and the hydrophobic nature of the ZG fillers. © 2022 The Author
The Effects of Dunaliella tertiolecta, Tetraselmis suecica and Nannochloropsis oculata as Food on the Growth, Survival and Reproductive Characteristics of Artemia urmiana
Abstract Artemia is the most widespread live food used in the production of different stages of many aquaculture organisms. It is a non-selective filter feeding organism. Generally, microalgae are the most favorable feeds for Artemia, particularly when the algal species have suitable size, digestibility and nutrient values. This study was performed to compare the efficiency of three microalgae namely Dunaliella tertiolecta, Tetraselmis suecica and Nannochloropsis oculata for growth, survival and reproduction efficiency of Artemia urmiana in laboratory conditions. Artemia cysts were harvested from Urmia Lake and hatched according to standard methods. Live microalgae were cultured using the f/2 culture medium. Artemia survival was determined in treatments on days 8, 11, 14, 17 and 20. The results indicated a significant difference (P<0.01) among three microalgae in terms of growth, survival rates and reproduction characteristics in A.urmiana. In spite of higher length growth of A.urmiana fed on N.oculata than T.suecica but survival and reproduction in A.urmiana fed on T.suecica was better than the first treatment. In general, D.tertiolecta was more efficient than T.suecica and N.oculata on A.urmiana, hence, it is preferred for feeding A.urmiana
Effects of environmental factors on the growth and development of Astacous leptodactylous in Aras River and its Reservoir
In order to study plankton population composition and species diversity in different regions of Aras Rivers and the evident reservoir sampling was performed monthly from determined sampling sites from April 2007 to March 2008. Sampling was conducted in Reservoir Lake by a PVC pipe with 2.25 m length and 5 cm diameter by columnar method. Besides, in more dipper (>5 m) sites, sampling conducted from bottom to surface with 1-m intervals (layer sampling) by a 2-liter Ruttner type sampler. In river due to water flow sampling was conducted by a scaled measure. Phytoplankton sampling was performed by 1-liter bottles. Zooplankton was sampled by filtering of 30 L through 55- micron plankton net. These samples were then transferred into bottles and sampling date and the name of station were attached on the bottles. Then, the samples were fixed immediately and transported to laboratory. It should be mentioned some physical parameters were determined in situ. Also, a 1liter and another 2-liter water were collected to determine chlorophyll a and chemical factors respectively. Samples were preserved in dark and cold place for a week. The upper layers (without phytoplankton) were removed and the lower layer (with phytoplankton) was sampled into 5-ml chambers. The enumeration and identification was performed by a Nikon TS100 inverted microscope with ×400 (Phytoplankton) and ×200 (Zooplankton) magnification according to Utermohl (1958) method. About 50 fields were enumerated for each sample. The comparison of physicochemical and biological factors with standard criterion indicated that the presence of a fertile plain, agricultural growth, drought and higher water demand in recent years, as well as, higher population density, the Nakhjavan city location and sewage water flows into the Aras reservoir, the lake is going to be an eutroph lake. Sampling of crayfish was performed from 5 sampling sites seasonally. Aras reservoir freshwater crayfish biomass was sampled in 1391, by putting 100 funnel-shaped nets. At each site one row nets composed of 20 nets were put by rocks, connecting robe and boat. Twenty four hours later, total freshwater cray fish was sampled (at least 300 crayfish was randomly sampled from each site). The samples were transported to laboratory and their sex, sex percentage, biometric characteristics including length, weight were recorded. Length and weight groups were estimated totally and for males and females in each season. The average total length and weight were 106.43 ± 7.94 mm and 35.81 ± 10.86 gr respectively which both are lower than West-Azarbaijan fisheries criterion. In this study only 18.99 percent contained a length higher than exporting level (120 mm). Yet, only 16.46 percent of harvesting had higher than 50 g (exporting level). With regard to data, freshwater shrimp (Astacus leptodactylus) in Aras dam reservoir stock has reduced. In general, male-female ratio was high. The comparison of growth equations confirms that males had higher weights than equal females. In recent years, the freshwater crayfish harvesting has been declined due to increased harvesting and over loading of nutrients into the lake
The Comparison of the culture operation of Artemia franciscana and parthenogenetic species on the sidelines of Qom Salt Lake
Qom Province with an area of 11,238 km^2 , surrounds about 0.68%of the country area and almost situated in the center of the country and enjoys a hot and dry climate . Because of the unique flora and fauna of the region especially the salt pools - hoze- Sultan and salt lakes enjoys a certain ecosystem in the country. Research has done in different parts of Iran and Qom province regarding the Artemia culture in salt lands that showed a great potential in the country and Qom province. The aim of this study that was held in order of Qom fisheries institute and environmental protection organization of that province and scientific leadership of Iranian Artemia Research Center, was the culture of Qom native Artemia and Artemia franciscana ( foreign species ) across Qom salt lake and determining the prevalence of cultured species in this region for this purpose, site selection and climatic and topographic data collection was held at 5 regions of Qom province. This regions were included margins of salt lake, and hoze sultan, shams abad drainage, railway station, and freshwater culture farm at the north east of Qom salt lake. margins of salt lake, and hoze sultan, were suitable for Artemia investment due to suitable climate and vast area, but they had problems in terms of technical facilities and access to areas . Also, the rail way station and plantation industry had dehydration problems. Therefore, after reviewing the field of agricultural water taken along the 45 km of Kashan and Qom Salt Lake were selected for the project because of the salty ecosystem similar to the lake, presence of salt water drainages downstream of the farm , technical facilities and a large area , soil texture and easy access to the area . For this purpose, six pools with 50 square meters near the reservoir pool available were constructed and 70 g native Artemia cysts of Qom and 23/3 g cysts of Artemia franciscana were hatched in Zooks of 10 liters for each pool ea of 50 square meters under standard condition (salinity 35 ppt pH =8, light lux 2000 and temperature 28°C). By calculating the useful volume of water for culture (112 cubic meters) and Hatching efficiency for native Artemia of Qom (40,000) and Artemia franciscana (120,000), the number of 25 nauplii per liter equal to the 2.8 million nauplii were released to each pool with size 4 × 12 m and high slope with area of 50 meter in the floor and 273 meters in the surface . Non- biological and biological studies, including algae and water analysis and population assessments were performed regularly in pools every 2 weeks. the culture period were from July to mid- October, 2009 for a period of 3/5 months. The results of algal study revealed more abundance of Cholestrium, Navicula, Nitzshia algae during culture period (105 days), that Amphora, etraselmis, Cymbella, Senedesmus, Dscillatoria, Gomphonema genera were observed, too. The results of water parameters analysis revealed that they should preserve at salinity 40–50 ppt, pH 8, water hardness 7000- 9000 mg. the results of population assessment showed a larger amounts of female broods of Qom Artemia at days 15,30 and 90 of culture with average number of 120.3, 68.8 and 29.5 per liter, respectively, comparing to Artemia franciscana with average number of 28.8, 17.5 and 7.7 per liter that was significant (p<0.05). The results indicated the greater development and adaptation of native Artemia of Qom at the culture ecosystem of Qom (Kesht va Sanaat Ab Shirin farm at the northeast of Qom salt lake). Harvesting of Artemia biomass of native Qom with the amount of 30 kg/100m^2 showed the production of native Artemia is relatively economic and during culture period (105 days) the mean cyst production for native Qom Artemia and Artemia franciscana were 193 and 123.5 individuals/liter, respectively. It can be concluded that native Qom Artemia enjoys a greater adaptation in growth and development with the arid ecosystem of the region and can be used as a valuable biologic stock in culturing purposes and developing native Artemia strains of the country and investments in construction of Artemia culture pilots in salt areas situated at Qom salt lake
Molecular barcoding of the Aras reservoir alga Microcystis aeruginosa (Kützing) Kützing 1846 by ITS-2 gene
Today, due to population increase and anthropogenic activities together with sewage and agricultural waste water entrance, aquatic ecosystems have been exposed to high pollutions. Phytoplankton is a group of water floating algae that have crucial roles in providing nutrients and oxygen for other organisms, nitrogen and CO_2 fixation. These organisms are considered as primary producers in aquatic ecosystems. They are found in various water habitats all over the world, affected by environmental variables such as pH, light and temperature and used for determination of water pollution degree and quality. Phytoplankton composition and density may be used as a complementary indicator of water trophy state. Phytoplankton communities indicate short and long term variations of aquatic systems. One of the most obvious problems in freshwater ecosystems is algal bloom or over growth of some blue- green algae which can decrease oxygen, and in some cases bring about toxin excretion and fish and human kills. In addition, many of bloom forming cyanobacteria produce secondary metabolites which can create sever poisoning in mammals including human. The genus Microcystis is a key bloom forming cyanobacteria in aquatic ecosystems. Populations of this genus form intense blooms in water bodies that has attracted more attentions in recent years. Various species of this alga have been distributed in stagnant and eutroph freshwater around the world. Microcystis has been defined by genetic criteria such as 16S rRNA molecular sequencing, but its classification in levels lower than genus is unclear and the presence of its classical morphospecies is doubtful. However, this genus creates sever blooms in eutrophic waters all over the world and many species produce toxins. Therefore, identification of its natural diversity in the levels lower than genus has high importance. However, several characteristics of Microcystis morphotypes which are classified a traditional species, actually are present and observed in different regions of the world. At present, they can be considered as morphospecies that belong to one genotype and have similar ecology. These traditional species with definite phenotypic and ecophysiological characteristics cannot be eliminated completely. Their identification is essential for ecological and ecotoxicological studies. Interistic transcribed separator (ITS) gene is a section of genome which is located between 16s rRNA and 23s genes. This gene has more heterogeneity than 16s rRNA; so it is used to identify many genera of cyanobacteria. The Aras reservoir located in the north-west of Iran plays important roles as fisheries, drinking and agricultural water supply and recreational activities in the region. The present thesis was undertaken to: analyze the Microcystis sp. populations by molecular methods such as ITS in Aras Reservoir. Samples for molecular analysis were collected from 10 sampling sites on 18 August 2013. Samples for molecular study of Microcystis were collected from two different depths (surface and 1 m depth) and transferred to laboratory without any treatments. Microscopic images of Microcystis were sent to professor Komárek and was confirmed
Determination of permitable distance between coldwater culture farms with common water supply in pirdanan river of West Azarbaijan
Regarding the increase in world population and decrease in fish stock, there is an urgent need to aquaculture practices. Coldwater fish culture is aiming at production and providing a part of protein needs of the country and a way reaching to self- sufficiency and preserve the water resources. Recently, multi- purpose use of water resources potential and especially the rivers of west Azarbaijan, for example, construction of fish farms at upstream of permanent rivers in order to make optimum use of the resources and the increase in employment has been considered . The waste water of these pools is usually discharged into the rivers. Regarding to increased production per unit area due to water resources and cold water fish culture restrictions to use regional facilities and fish farm construction, it is nessacery to determine limits between 2 farms. In this study with the goal of evaluation of the impacts of trout farm effluents on water quality parameters of Pirdanan River, the factors of water current, temperature, pH, EC, TDS, TSS, DO, BOD_5, NH_3, N-NO_2, N-NO_3, TP P-PO_4 according to standard methods were determined montly during 2014-2015 . Sampling sites were entrance, exit of Maroofi trout farm and the distances of 700, 1400, 2100 and 2800 m after the farm exit. Seasonal sampling of macro invertebrates from mentioned sites was conducted using stone leaching. The family and genus of macro invertebrates were identified using identification keys and abundance of macro invertebrate phylums for each site was determined. The results revealed that the values for water current, EC, TDS, TSS, N-NO_3 were significant. the values of water temperature, BOD5, TDS, TSS, N-NO^3- , N-NO^2-, NH_3, P-PO^4- , NH4+, N-NH3 were increased in site 2 compare to site 1 in all months and gradually in the river and its self- purification were decreased. In this study, 4 phylums, 4 classes, 7orders and 14 families of macroinvertbrates were identified from Pirdanan River. Ephemeroptera had the highest abundance in site 4; while Diptera had the highest abundance in site 2 (exit). Regarding that most of Diptera macro invertebrates were from Chironomidae, so it can be concluded that site 2 was the most pollutant site and sites 5 and 6 were more suitable condition. Therefore, considering the physic- chemical factors and macro inverteberates indices, 2100 m from entrance, (site 5) is recommended compliance with veterinary organization rules and other conditions of aquatic engineering, environmental and water operation standards
Determination of optimum dosage of Ovaprim injectionon artificial spawning efficiency of Esox lucius
This project was conducted to goal of optimum dosage determination of ovaprim injection to artificial spawning efficiency of Esox lucius. The research implemented by 4 treatments with 3 replicates for each ones. 3 female and 6 male brooders injected in each replicate. The animals in 1, 2 and 3 treatments injected by 10, 20 and 30 µg/kg BW, respectively, and 4th treatment as a control injected with 4 mg/kg BW pituitary gland extract. Average weight of brooders were 1361±521, 1376±954, 1009±160 and 1100 ±422 g in 1, 2, 3 and 4 treatments in females and 689±145, 734±197, 547±118 and 794±238 g in males, respectively. In addition, positive response percent to hormone injection were measured 77.8 ±19.24 , 88.9 ± 19.24 , 55.5 ±50.91 and 55.5 ± 19.24 % in 1, 2, 3 and 4 treatments in female and 94.4 ± 9.58, 88.9 ±19.26 , 83.3±28.86 and 88.9 ± 19.26 % in male brooders, respectively, but there was no significant different between all of treatments (p<0.05). Incubation period from fertilization till hatching step in 7 to 15 ˚C was 5 to 10 days with average of 7±1.5 days. Fertilization content was in 1 to 4 treatments measured 87.1±10, 88.04±7.7, 83.9±5.2 and 72.4±19.7 %, respectively and also the treatments didn’t show any different significantly together (p<0.05). Average percentage of eyed eggs 66.6±15.9 in treat 1, 61.2±22.3 in treat 2, 58.3±10.7 in treat 3 and 56.1±15.04 in treat 4, without any significant different between of them (p<0.05). Hatching of eggs mean were measured 27.41±19.8 in treat 1, 39.53±26.9 in treat 2, 95.18±5.6 in treat 3 and 26.78±12.4 in treat 4, and significant different observed between of them too (p<0.05).In the other hand, mean percent of larvae with active feeding in these treatments were measured 18.77±14.6, 20.1±8.51, 55.6±11.6 and 14.51±7.72 as the treatments had significant different (p<0.05). Also, the best temperature and dosage injection of ovaprim hormone was 9 to 12.5 ˚C and 20µg/kg BW, respectively. The end of trial, from 103740 larvae introduced to earthen pond obtained 8000 fingerlings with weight of 2.68±0.6 g and length of 6.96±0.51 cm
Thin film nanocomposite membranes of superglassy PIM-1 and amine-functionalised 2D fillers for gas separation
Loss of free volume over time (i.e. aging) is the main hurdle towards the commercial use of super glassy polymers for gas separation membranes. Aging takes place at a much faster rate in polymeric thin films, with permeability reductions of over 50% in only a few days. In this work 2D reduced holey graphene oxide (rHGO) nanosheets containing amine groups were added into thin films of the super-glassy polymer of intrinsic microporosity PIM-1. At filler loadings of 1 wt% of rHGO-tris(4-aminophenyl)amine, the CO2 permeance after 1 year of physical aging was 846 ± 37 GPU, which remained very close to that of the fresh membrane tested right after preparation (1050 ± 70 GPU), and was double that of 1 year-aged purely PIM-1 thin film composite membranes (432 ± 4 GPU). Membranes with lower filler concentrations of 0.1 wt% showed CO2 permeance values of 604 ± 34 GPU after 1 year of aging, but they aged quite rapidly; the initial CO2 permeance values of the fresh thin film nanocomposite (TFN) membrane at filler loading of 0.1 wt% was 3351 ± 662 GPU. The aging behaviour was also investigated in several tens of micrometres thick membranes (up to 2 years) for filler loadings of 0.1 wt% and the gas separation performance showed similar tendencies to that of thin films; leading to higher CO2 permeability without sacrificing CO2/CH4 selectivity
Spatial distribution of cutaneous anthrax in western Iran from 2009 to 2016: Geographic information system mapping for predicting risk of anthrax outbreaks
To explore the spatial accumulation of diseases and their aggravating factors are essential in all public health. This study attempts to use geographic information system (GIS) to provide more information about the incidence and future of anthrax. Methods: Patients were diagnosed with anthrax in Kurdistan Province from 2009 to 2016. Data was then exported into ArcGIS software version 9 and the required layers for years and areas were added.Final map for each year was drawn up, pointing out the hot spots and predicting its future pattern. Results: Most cases were reported in females (57 cases, 54.80 ), and the lower body limbs were most affected (63 cases, 60.57). The highest numbers of incidences were related to the cities of Marivan, Saqez and Divandareh, with more concentration in the central parts of the province, rather than borderline areas. The highest percentage of the probable incidence of the disease was in Sanandaj (57.74) with a potential susceptible area of 1 729.12 km2 and then in Saqez (54.36) with a potential area of 2 422.4 km2. Conclusions: A vast area of Kurdistan Province is high risk for new cases of anthrax. Therefore, it is important to scale up the surveillance system in the province. © 2020 Asian Pacific Journal of Tropical Medicine Produced by Wolters Kluwer- Medknow. All rights reserved