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The port of Ténès, located at West of Algiers, is a medium of intense anthropic activities. Its pollution was monitored using a sampling technique. The analysis of the parameters: pH, temperature, electrical conductiv concentration of heavy metals has been carried out by the atomic absorption while scanning the wavelengths varying from 217.0 nm at 228.8 nm. The evolution of the nitrate and nitrite content was obtained by spectrophotometer. Their spatio the Geographic Information System (GIS) software. The high toxicity of seawater is due to the presence of lead and cadmium with concentrations exceeding 60 times the normal value (0.015 mg/l). Moreover, the deficit in D.O aggression is related to the industrial discharges in the port area.

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Knowledge of gas holdup is important for the development of the three-phase fluidized bed reactors. This work concerns the study of the effect of different operating conditions on gas retention in a turbulent bed contactor type 2 (TBC), such as superficial gas and liquid velocities, liquid to gas mass flows ratio (L/G), particle diameter and density, static bed height and free-open area of the supporting grid. The influence of the free area of the packing support grid (φ) on gas holdup was demonstrated and proved. The gas holdup increased to 22.92 % when φ decreased from 0.82 to 0.32. The experimental data (1746) led to the development of two correlations to predict gas holdup, one of which incorporated the ratio (L/G) which is an important design factor for gas-liquid contactors. The predicted results of holdup gas were in good agreement with the experimental data.

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The vibrational spectra of crystalline nitric acid hydrates have been investigated at the periodic ab initio quantum level by using a Gaussian type basis set and the hybrid B3LYP Hamiltonian with CRYSTAL06 code. Using as input the X-ray structures of crystalline nitric acid monohydrate NAM, dihydrate α-NAD and trihydrate β-NAT, the inner coordinates within each unit cell have been optimized. The calculated structures of these atmospherically relevant systems are used in the evaluation of their vibrational normal modes. The obtained theoretical results show in general a good agreement compared to the observed spectra in the range 4000- 600 cm-1 and 200-20 cm-1 for infrared and Low-Frequency Raman spectra, respectively.

In this work, the hydrodynamics of the turbulent bed contractor (TBC) have been studied in terms of bed expansion (Hd/Hst) using a particular approach for the prediction of this important property for the design of such equipment. The study is based on 1604 sets of experimental data of the bed expansion, obtained by varying the operating variables (gas velocity, liquid spray, packing characteristics, static bed height and free opening of the supporting grid. The prediction of the bed expansion necessitates the estimation of gas and liquid holdups. To achieve this, we employed a variety of correlations derived from existing literature, comprising six equations for gas holdup and twenty equations for liquid holdup estimation. Out of a total of 120 cases, bed expansion was estimated, and the accuracy of the model was evaluated by calculating the mean absolute error in percentage (MAPE), root mean square error (RMSE), correlation coefficient (?XY), and explained variance (VECV). This study enabled the identification of suitable correlations for gas and liquid holdups, leading to predictions with acceptable errors. Furthermore, statistical analysis was employed in a subsequent phase of the study to determine the most appropriate correlations for predicting bed expansion among those proposed by various authors.