The objective of this study is to determine the influence of soil physico-chemical factors on the spatial distribution of matorrals in the plain from Remchi to Béni-Saf located in the western region of Algeria. T...The objective of this study is to determine the influence of soil physico-chemical factors on the spatial distribution of matorrals in the plain from Remchi to Béni-Saf located in the western region of Algeria. This study informs us of the relationships that soil can have on the diversity of matorrals. On the bioclimatic level, the region is characterized by semi-aridity accentuating the phenomena of thérophysation. Soil analyzes carried out using known methods (Stokes Particle Size Method, Electrometric Method for pH, 1/5 Extract Method for Electrical Conductivity, Bernard Calcium Method for CaCO3, Anne Method for Organic Carbon). The results show a textural diversity;sandy-muddy “Remchi”, sandy “Rachgoun 1 and Rechgoun 2”, not far from Béni-Saf. The low clay content (Remchi: Profile 1: Horizon 1: Clays 10%, Profile 2: Horizon 1: Clays 16%, Profile 3: Horizon 1: Clays 5%, Rechgoun: Profile 1: Horizon 1: Clays 3%, Profile 3: Horizon 1: 2% Clays and Horizon 2: 3% Clays) leads to poor structural stability leading to degradation of the soil surface through erosion. The latter is revealed by the presence of small erosion claws visible on these rough slopes or almost.展开更多
In this work, we are interesting in the measurement of thermal conductivity (on the surface and in-depth) of Porous silicon by the micro-Raman spectroscopy. This direct method (micro-Raman spectroscopy) enabled us to ...In this work, we are interesting in the measurement of thermal conductivity (on the surface and in-depth) of Porous silicon by the micro-Raman spectroscopy. This direct method (micro-Raman spectroscopy) enabled us to develop a systematic means of investigation of the morphology and the thermal conductivity of Porous silicon oxidized or no. The thermal conductivity is studied according to the parameters of anodization and fraction of silicon oxidized. Thermal transport in the porous silicon layers is limited by its porous nature and the blocking of transport in the silicon skeleton what supports its use in the thermal sensors.展开更多
We consider in this research an age-structured alcoholism model.The global behavior of the model is investigated.It is proved that the system has a threshold dynamics in terms of the basic reproduction number(BRN),whe...We consider in this research an age-structured alcoholism model.The global behavior of the model is investigated.It is proved that the system has a threshold dynamics in terms of the basic reproduction number(BRN),where we obtained that alcohol-free equilibrium(AFE)is globally asymptotically stable(GAS)in the case R_(0)≤1,but for R_(0)>1 we found that the system persists and the nontrivial equilibrium(EE)is GAS.Furthermore,the effects of the susceptible drinkers rate and the repulse rate of the recovers to alcoholics are investigated,which allow us to provide a proper strategy for reducing the spread of alcohol use in the studied populations.The obtained mathematical results are tested numerically next to its biological relevance.展开更多
文摘The objective of this study is to determine the influence of soil physico-chemical factors on the spatial distribution of matorrals in the plain from Remchi to Béni-Saf located in the western region of Algeria. This study informs us of the relationships that soil can have on the diversity of matorrals. On the bioclimatic level, the region is characterized by semi-aridity accentuating the phenomena of thérophysation. Soil analyzes carried out using known methods (Stokes Particle Size Method, Electrometric Method for pH, 1/5 Extract Method for Electrical Conductivity, Bernard Calcium Method for CaCO3, Anne Method for Organic Carbon). The results show a textural diversity;sandy-muddy “Remchi”, sandy “Rachgoun 1 and Rechgoun 2”, not far from Béni-Saf. The low clay content (Remchi: Profile 1: Horizon 1: Clays 10%, Profile 2: Horizon 1: Clays 16%, Profile 3: Horizon 1: Clays 5%, Rechgoun: Profile 1: Horizon 1: Clays 3%, Profile 3: Horizon 1: 2% Clays and Horizon 2: 3% Clays) leads to poor structural stability leading to degradation of the soil surface through erosion. The latter is revealed by the presence of small erosion claws visible on these rough slopes or almost.
文摘In this work, we are interesting in the measurement of thermal conductivity (on the surface and in-depth) of Porous silicon by the micro-Raman spectroscopy. This direct method (micro-Raman spectroscopy) enabled us to develop a systematic means of investigation of the morphology and the thermal conductivity of Porous silicon oxidized or no. The thermal conductivity is studied according to the parameters of anodization and fraction of silicon oxidized. Thermal transport in the porous silicon layers is limited by its porous nature and the blocking of transport in the silicon skeleton what supports its use in the thermal sensors.
基金supported by DGESTR of Algeria No.COOL03UN130120200004.
文摘We consider in this research an age-structured alcoholism model.The global behavior of the model is investigated.It is proved that the system has a threshold dynamics in terms of the basic reproduction number(BRN),where we obtained that alcohol-free equilibrium(AFE)is globally asymptotically stable(GAS)in the case R_(0)≤1,but for R_(0)>1 we found that the system persists and the nontrivial equilibrium(EE)is GAS.Furthermore,the effects of the susceptible drinkers rate and the repulse rate of the recovers to alcoholics are investigated,which allow us to provide a proper strategy for reducing the spread of alcohol use in the studied populations.The obtained mathematical results are tested numerically next to its biological relevance.
