26 research outputs found
Path integral for relativistic oscillators: model of the Klein-Gordon particle in AdS space
Explicit path integration is carried out for the Green's functions of special
relativistic harmonic oscillators in (1+1)- and (3+1)-dimensional Minkowski
space-time modeled by a Klein-Gordon particle in the universal covering
space-time of the anti-de Sitter static space-time. The energy spectrum
together with the normalized wave functions are obtained. In the
non-relativistic limit, the bound states of the one- and three-dimensional
ordinary oscillators are regained.Comment: 23 pages, no figures. Accepted for publication in Eur.Phys.J.
Algebraic treatment of the confluent Natanzon potentials
Using the so(2,1) Lie algebra and the Baker, Campbell and Hausdorff formulas,
the Green's function for the class of the confluent Natanzon potentials is
constructed straightforwardly. The bound-state energy spectrum is then
determined. Eventually, the three-dimensional harmonic potential, the
three-dimensional Coulomb potential and the Morse potential may all be
considered as particular cases.Comment: 9 page
Contribution à l’étude microbiologique des eaux de l’oued Medjerda dans l’extrême Est Algérien : Souk Ahras
La Medjerda constitue l’un des plus importants oueds de l’Est algérien. Les analyses de la flore microbienne des eaux procurées de six stations pendant les périodes humides et sèches de l’année 2009 ont montré que la notion de saison a une influence certaine sur la concentration en germes. Malgré la forte charge en bactéries indicatrices de la contamination fécale (germes totaux, coliformes fécaux, streptocoques fécaux et Clostridium sulfito-réducteurs), les germes pathogènes du genre Salmonella n'ont pas été détectés. L'existence éventuelle de ces germes à l'état viable mais non cultivable constituerait un risque particulier du fait que les bactéries survivant à cet état ne sont pas détectables par les techniques de culture classique. Par ailleurs, les levures et les moisissures sont présentes dans tous les sites étudiés, ce qui rejoint nos conclusions concernant les germes précédemment étudiés. Nos résultats montrent une dégradation importante dans la qualité des eaux de l’oued Medjerda notamment dans les sites 3 (cité Zarouria) et 4 (cité hospitalière).Mots clés : Oued Medjerda – Eau – Environnement – Pollution - Qualité microbiologique.Medjerda is one of the most important oueds in eastern Algeria. During the late wet and dry periods of the year 2009, the microbiological water quality of six stations was studied and showed that the concept of season has some effects on increasing concentration of germs during the dry season compared to the wet season. Despite the heavy load of faecal indicator bacteria (Plate Count, fecal coliforms, faecal streptococci and sulphite-reducing Clostridium), pathogens of Salmonella genus were not detected. The probable existence of these organisms in a viable state but non- cultivable constitutes a particular risk because the bacteria surviving in this state are not detectable by conventional culture techniques. Moreover, the yeasts and molds are present in all sites which join our conclusions regarding the seeds previously studied. The results show a significant impairment of Medjerda water quality especially in sites 3(Zarouria street) and 4 (Hospital street).Keywords : Oued Medjerda – Water – Environment – Pollution - Microbiological quality
Physicochemical Characteristics And Pollen Spectrum Of Some North-East Algerian Honeys
The qualities of seventeen honey samples harvested from the North-East
areas of Algeria were evaluated by determining the pollen spectrum,
pollen number quantity and physicochemical attributes. Pollen analysis
can therefore be useful to determine the geographical and botanical
origin of honeys. The following determinations were carried out: pH,
density, acidity (free, lactone and total), moisture, electrical
conductivity, hydroxymethylfurfural, diastase activity, apparent
sucrose, and proteins. The results obtained in the present study show
the variability of chemical composition of the honey samples. It proved
that nine natural honeys are of blossoming origin; suitable for
consumption and that one (T5 conferred Bougous) can be used with fine
dietetics, it is very rich in pollen which is regarded as protein
source. The remainder, eight honeys, were not in conformity with the
International Regulatory Standards, their sugar contents (Sucrose) and
hydroxymethylfurfural exceeded the International Regulatory Standards
Review by the International Honey Commission, this was probably due to
use of syrup for the over-feeding the bees during the spring. The
sample Bouhachana (G1) had high water content (more than 20%), low
density and electrical conductivity higher than 5 µS/cm, which
makes it likely to undergo fermentation and degradation. Honeys of
Guerguour (T1), Boutheldja (T2) and Bouhadjar (T3) had pH lower than
the European standards concerning the quality control of the foodstuffs
(exp. honey). These samples are fragile; so we cannot preserve them for
a long period. The palynological analysis (qualitative and
quantitative) of the harvested samples in the area, showed the absence
of a honey obtained from only one melliferous plant. All honeys are
polyfloral exits of the several plant species visited by the worker
bees during their blossoming periods. Three families are the most
represented in the groups of pollen of accompaniment (the secondary
pollen ranged between 16-45%) and the pollen considered as rare (minor
pollen 3-15%) in the counted total number of the pollen grains in 10
grams of honey. These forager honey families are: Myrtaceae presented
by the Eucalyptus, Papilionaceae presented by Hedysarum coronarium
which is a forager plant characterized by a very vast surface of
development, and Rosaceae represented by orchard and forest species.The
pollen grain number counted in honeys is very significant (between 80
000 and 24 832 000pollen grain), what makes it possible to classify the
samples analyzed among the categories rich in pollen