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The assessment of the physicochemical quality of water intended for irrigation of Oued Méskiana (Oum El Bouaghi) Algeria

Abstract

The aquatic ecosystem of the Meskiana Valley (wilaya of Oum El Bouaghi) covers a large area with a permanent flow and a semi-arid climate characterized by a strong evapotranspiration. In order to determine the Physico-chemical quality, pollution and salinity of the water of the river of Meskiana and more particularly in its downstream part which is exposed to wastewater discharges, analyses were carried out at the level of three sampling points: witness, the upstream (before spill), downstream (after spill)). In order to prevent the risk of alkalization and salinization of soil, the sodium absorption rate (SAR) and the percentage of sodium were determined and represented on the Wilcox and Riverside diagram. The high concentrations of polluting chemical elements and excessive salinity obtained at the downstream site show a high risk of pollution and salinization.

Open access
Biodiversity, Distribution and Ecology of Testate Amoebae (Arcellinida and Euglyphida) from the Bulgarian Black Sea Coast and the related brackish lakes. A Synthesis

Abstract

The studies on the marine and freshwater testate amoebae of the Bulgarian Black Sea littoral and some related coastal brackish lakes are briefly reviewed. So far, a total of 184 species and subspecies of testate amoebae from 18 families and 45 genera from orders of Arcellinida and Euglyphida were published in national and international journals. The underground waters of the Bulgarian marine sand supralittoral are better studied than the related continental lakes. A total of about 45 species of marine interstitial testate amoebae are known, so far, and a big part of them were for the first time described from the Black Sea littoral. It’s interesting to note the presence in the marine underground waters of the Black Sea littoral of many freshwater testate amoebae also, considered by us as eurybionts. That is due of the low and variable salinity of the littoral Black Sea waters during the year. The presence of some psammobiotic testate amoebae as Psammonobiotus lineare and Corythionella georgiana in some related brackish lakes is also of ecological interest. The general conclusion of the present synthesis is that the testate amoebae fauna of the Bulgarian Black Sea coast and the related with it many brackish and freshwater littoral lakes is few known yet and need more active researches.

Open access
Calculated neutron energy dependence of the dose-response of large recombination chamber

Abstract

A model of REM-2-type chamber was modeled with MCNPX code to study the dose-response to monoenergetic neutrons in wide energy range from thermal to 20 MeV for various compositions of gas in the chamber. The energy dependence of the total dose absorbed in the filling gas was compared with the energy dependence of ambient absorbed dose D*(10) and with experimental data. The results of the studies will be useful for designing new, improved generation of recombination chambers.

Open access
Chemical Composition of the Essential Oil of Aerial Parts of Thymus ciliatus (Desf.)

Abstract

The essential oil of the aerial parts of Thymus ciliatus (Desf.) belonging to the Lamiaceae family, was obtained by steam distillation and analyzed by GC-FID and GC-MS. 75 components were identified corresponding to 95.57% of the total oil. The major constituents of the oil were: elemol (6.80%), carvacrol (5.86%), γ-muurolene (5.18%), β-sesquiphellandrene (5.09%), bicyclogermacrene (5.04%), β-pinene (4.49%) and curcumene (4.20%), together with other compounds at relatively low levels: 1,8-cineol (3.66%), β-eudesmol (2.92%), β-bisabolene (2.81%), β-silinene (2.75%), camphor (2.64%), germacrone (2.34%), α-zingiberene (2.12%), δ-cadinene (2.08%), caryophyllene oxide (1.90%), spathulenol (1.88%), □-caryophyllene (1.88%), ar-turmerone (1.79%), α-pinene (1.52%), limonene (1.52%), selina-4,11-diene (1.46%), curzerenone (1.41%), germacrone B (1.37%), bornyl acetate (1.31%), β-farnesene (1.28%), borneol (1.23%), myrtenal (1.16%), zingiberenol (1.15%) and sabinene (1.13%). These results differ from those of previous studies reported on this species collected from other regions of Algeria and Morocco.

Open access
Cost-effective approach to lung cancer risk for a radiological dispersal device (RDD) scenario

Abstract

A release of radioactive material into the environment can lead to hazardous exposure of the population and serious future concerns about health issues such as an increased incidence of cancer. In this context, a practical methodology capable of providing useful basic information from the scenario can be valuable for immediate decisions and future risk assessment. For this work, the simulation of a radiological dispersal device (RDD) filled with americium-241 was considered. The radiation dose simulated by the HotSpot code was used as an input to the epidemiological equations from BEIR V producing the data used to assess the risk of lung cancer development. The methodology could be useful in providing training for responders aimed to the initial support addressed to decision-making for emergency response at the early phase of an RDD scenario. The results from the simulation allow estimating (a) the size of the potentially affected population, (b) the type of protection action considering gender and location of the individuals, (c) the absorbed doses, (d) the matrix of lung cancer incidence predictions over a period of 5 years, and (e) the cost-effectiveness in the initial decision environment.

Open access
The effects of fuel type on control rod reactivity of pebble-bed reactor

Abstract

As a crucial core physics parameter, the control rod reactivity has to be predicted for the control and safety of the reactor. This paper studies the control rod reactivity calculation of the pebble-bed reactor with three scenarios of UO2, (Th,U)O2, and PuO2 fuel type without any modifications in the configuration of the reactor core. The reactor geometry of HTR-10 was selected for the reactor model. The entire calculation of control rod reactivity was done using the MCNP6 code with ENDF/B-VII library. The calculation results show that the total reactivity worth of control rods in UO2-, (U,Th)O2-, and PuO2-fueled cores is 15.87, 15.25, and 14.33%Δk/k, respectively. These results prove that the effectiveness of total control rod in thorium and uranium cores is almost similar to but higher than that in plutonium cores. The highest reactivity worth of individual control rod in uranium, thorium and plutonium cores is 1.64, 1.44, and 1.53%Δk/k corresponding to CR8, CR1, and CR5, respectively. The other results demonstrate that the reactor can be safely shutdown with the control rods combination of CR3+CR5+CR8+CR10, CR2+CR3+CR7+CR8, and CR1+CR3+CR6+CR8 in UO2-, (U,Th)O2-, and PuO2-fueled cores, respectively. It can be concluded that, even though the calculation results are not so much different, however, the selection of control rods should be considered in the pebble-bed core design with different scenarios of fuel type.

Open access
Ethnobotanical study of Belezma National Park (BNP) plants in Batna: East of Algeria

Abstract

The present work focuses on an ethnobotanical study of medicinal plants in the Belezma National Park (BNP), which is located in Batna city. It was conducted to precise on the medicinal plants in the park and gathers all the information on the therapeutic practice used by the local inhabitants of the study area. Using 300 questionnaire cards, ethnobotanical surveys of BNP were conducted during two campaigns (2017 and 2018). The obtained results allowed us to identify 50 medicinal plants used by the population of the region, which are divided into 27 families and 46genus.

The obtained results show both leaves and stems are mostly used for diseases’ treatment in the form of a decoction with a rate of 42.34%. For the treated diseases, the digestive disorders occupy the first place with a rate of 34.01%, followed by uro-genital diseases with a rate of 17.56%, 11.20% for respiratory diseases, 11.84% for orthopedic diseases and 6.23% for cardiovascular.

The founded results could be a database for research on phytochemistry and pharmacology for the national medicinal flora and the population of the BNP region. Also, they constitute a very valuable source of information.

Open access
Green-extraction of essential oil of the species Ruta chalepensis L.: gas chromatography-mass spectroscopy-infra red analysis and response surface methodology optimization

Abstract

The objective of the present study was the optimization of the parameters affecting the hydrodistillation of Ruta chalepensis L. essential oil using response surface design type Box-Behnken. After an appropriate choice of three parameters, 15 experiments were performed leading to a mathematical second-degree model relating the response function (yield of essential oil) to parameters and allowing a good control of the extraction process. The realization of the experiments and data analysis was carried out by response surface methodology (RSM). A deduced second-order polynomial expression was used to determine the optimal conditions necessary to obtain a better essential oil yield. These optimized operating conditions were: a granulometry of 2 mm, a condensation-water flow rate of 3.4 mL/min and an extraction time of 204 min. Analysis of variance (ANOVA) indicates that the generated second-order polynomial model was highly significant with R2=0.9589 and P<0.006. The gas chromatography-mass spectrometry analysis of essential oil extracted from the Ruta chalepensis L. aerial parts revealed the presence of 2-undecanone, 2-nonanone and 2-decanone as major components.

Open access
Influence of biological removal of lactose on the physical and chemical parameters of crude sweet whey

Abstract

The crude sweet whey is an effluent and a co-product of cooked and pressed cheeses and casein, released into the environment without prior treatment (case of Cheese Dairy Sidi Saada, Yellel, Relizane, Algeria) affect the quality of freshwater ecosystems (Oued Mina, Relizane, Algeria).Our study focused on the control of the physical and chemical parameters of crude sweet whey and delactosed whey.The results showed that the applied bioprocess modified the physical and chemical parameters of crude sweet whey such as :density,dry matter,refractive index,viscosity,ash,pH and electrical conductivity, acidity,proteins and lactose; for this purpose these findings depended on the operating conditions, and the composition of the whey put in treatment.

Open access