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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
Extension of Critical Difference for Product Comparison. Application to Tobacco Products

Summary

The differences or equivalence of products depend on various sources of variability like analytical methods, manufacturing processes, agricultural practices and environmental conditions. In addition, the capacity to compare and discriminate accurately two products is impacted by the number of characteristics considered for the comparison. Previously, it has been shown that a comparison of two products can be performed using the critical difference (CD), because it takes into consideration both the variability of measurements and laboratories. However, some additional sources of variability need to be added in the comparison when products were not manufactured at the same period of time or in the same factory. Here, an extended critical difference is proposed including manufacturing process variability according to the number of samples and batches collected for each product. The general formula and specific cases corresponding to different situations (one vs two labs, short vs long periods of time, same vs different periods of time, one vs several batches) are given.

Open access
Fabrication and Characterisation of ZnO Thin Film by Sol–Gel Technique

Abstract

We investigated the structural and optical properties of zinc oxide (ZnO) thin film as the n-type semiconductor. In this work, the sol–gel method used to fabricate ZnO thin film on glass substrate with 0.5 mol/l of zinc acetate dehydrates. The crystals quality of the thin film analyzed by X-ray diffraction and the optical transmittance was carried out by an ultraviolet-visible spectrophotometer. The DRX analyses indicated that ZnO film have polycrystalline nature and hexagonal wurtzite structure with (002) preferential orientation and the measured average crystallite size of ZnO of 207.9 nm. The thin film exhibit average optical transparency about 90 %, in the visible region, found that optical band gap energy was 3.282 eV, the Urbach energy also was calculated from optical transmittance to optimal value is 196.7 meV.

Open access
Gas Chromatography-Tandem Mass Spectrometry Method for Selective Detection of 2-Nitropropane in Mainstream Cigarette Smoke

Summary

Although 2-nitropropane is a potentially harmful compound present in cigarette smoke, there are few fully-validated, modern methods to quantitate it in mainstream cigarette smoke. We developed an isotope dilution gas chromatography-tandem mass spectrometry (ID-GC-MS/MS) method for the detection of 2-nitropropane in mainstream cigarette smoke. The vapor fraction of mainstream cigarette smoke was collected in inert polyvinyl fluoride gas sampling bags and extracted with hexanes containing isotopically labeled internal standard, then purified and concentrated via solid-phase extraction using a normal phase silica adsorbent and a 100% dichloromethane eluant. This method is sensitive enough to measure vapor phase 2-nitro-propane concentrations in the nanogram range, with a 19 ng per cigarette method limit of detection. Product variability estimated from the analysis of 15 cigarette products yielded relative standard deviations ranging from 5.4% to 15.7%, and estimates of precision from two quality control products yielded relative standard deviations of 9.49% and 14.9%. Under the Health Canada Intense smoking regimen, 2-nitropropane in machine-generated mainstream smoke from 15 cigarette products ranged from 98.3 to 363 ng per cigarette.

Open access
Germanium Gradient Optimization for High-Speed Silicon Germanium Hetero-Junction Bipolar Transistors

Abstract

The effect of germanium trapezoidal profile shape on the direct current (DC) current gain (β F), cut-off frequency (f T) and maximum oscillation frequency (f MAX) of silicon-germanium (SiGe) hetero-junction bipolar transistors (HBTs) has been investigated. The energy balance (EB), hydrodynamic (HD) and drift-diffusion (DD) physical transport models in SILVACO technology computer aided design (T-CAD) simulator were used. It was found that the current gain values using energy balance model are higher than hydrodynamic and much higher than those corresponding to drift-diffusion. Moreover, decreasing the germanium gradient slope towards the collector side of the base enhances the maximum oscillation frequencies using HD and EB models whilst, they remain stable for DD model.

Open access
GPR Application for Risks Detection in Subsurface Engineering Construction Projects

Abstract

The aim of this work is to study and explore the causes of the landslide in different locations using Ground Penetrating Radar (GPR) technology. GPR uses the electromagnetic method related the high-frequency pulse that used widely in various field. The experimental study focused on the investigation of the landslide in the road by GPR method with antenna 200 MHz. The landslides become serious problems and required various technique and methods to investigate it in several places. GPR measurements present a useful technique for studies and investigation of the problem. The GPR can be categorized in the first place as an experimental method surveys landslide depths were recognized at 1-10 m below the natural terrain level. The results obtained revealed the causes of landslides on the road.

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
Integrated Management - a Basic Component for Building a Quality System in Construction

Abstract

From ancient times, mankind needed organization and coordination to be able to carry out its projects. Thus, over time, as requirements grew larger, it naturally emerged the necessity, development and improvement, of the skills of manager, coordinator, of a project team.

The paper develops the integrated management concept and tries to apply it for quality system management in construction.

This paper uses the method of the synthesis of the studied documents to demonstrate the necessity to implement integrated management.

Open access
Interpretation of the Miocene fossils in the Strymon basin in Northern Greece to determine their habitat

Abstract

The sedimentary sequences of the upper Miocene in the Strymon basin in Northern Greece are composed of sedimentary rocks and are separated on an entirely new lithostratigraphic shape. Fossil-fauna has been collected from specific parts of the described geological sections, which mainly include mollusks from Bivalvia and Gastropoda. From laboratory research on the micro-fauna and micro-flora a number of taxonomic units of Foraminifera were determined and representatives of Actinozoa, Bryozoa, Crinoidea, Ostracoda, Otolithus, Diatomeae and Charophyta were found, which give a more-complete biostratigraphical image of the sediments. Based on these investigations with the use of the biofacial analysis, through the study of palaeoecology data of the fossils, three basic types of palaeohabitat and development of organisms were identified and a new palaeogeographic interpretation of the depositional environments in the Miocene basin is given.

Open access