Applications of biological markers in assessing the organic richness of the surface sediments of Suez Gulf,Egypt

The semienclosed Suez Gulf records various signals of high anthropic pressures from surrounding regions and the industrialized Suez countries. The sedimentary hydrocarbons have been studied in six coastal stations located in the Gulf of Suez. Nonaromatic hydrocarbons were analyzed by GC/FID and GC/MS to assess organic content in surface sediments of Suez Gulf, Egypt, depending on alkane, terpane, and sterane biological marker indicators. The results showed that the hydrocarbons are originated from multiple terrestrial inputs, biogenic and pyrolytic. Several ratios hydrocarbons indicated the predominance of petrogenic in combination with biogenic hydrocarbons.     

Method of stochastic prediction of population estimates based on Kendall's birth and death process

"An attempt has been made to incorporate density and time-dependent birth and death rates into the generalized birth and death process given by Kendall (1948). The probability generating function of the process has also been investigated. A simple method of estimating the parameters of the process has been illustrated in the text. The applicability of the method for predicting the population of India, starting from the several deterministic projection figures given for any base year, is also discussed in the text."     

Kinetic investigation of the radical polymerization of N-acryloylpiperidine in solution

The kinetics of free radical polymerizations of N-acryloylpiperidine (NAPi) were studied in benzene (Bz) using 2,2′-azobisisobutyronitrile (AIBN) as initiator. The activation energy was determined to be 111.7 kJ mol^?1. The overall rate of polymerization of the NAPi-AIBN-Bz system at 60°C was investigated as a function of monomer and initiator concentrations. Deviation from normal kinetics was observed with an order of 1.48 with respect to the monomer. The observed dependence of the rate constants k_p/k on monomer concentration could not be explained by the diffusion theory or the theory of electron donor-acceptor (EDA) complexes. The observed data have, however, been satisfactorily interpreted by the ‘hot’ radical theory.     

Effect provenance of organic matters in surface sediments from coastal stations in the Gulf of Suez Gulf,Egypt: An implication from occurrence of triterpanes and steranes fragmentgrams

Effect of provenance of organic matter evaluated through the distribution of occurrence of triterpanes and steranes in surface sediments from coastal stations located in the Gulf of Suez Gulf. The samples have been studied in four coastal stations located in the Gulf of Suez namely: Al–Nasr Oil Company (NPC), West outlet of SOPC, Inlete of SOPC, and El-Sukhna of Loloha Beach. Saturated hydrocarbons were analyzed by gas chromatography–mass spectrometry, to assessing of organic content and maturity level of the sediments. The results showed that the hydrocarbons are originated mainly from predominance of petrogenic and biogenic hydrocarbons with high maturity level.     

In situ preparation of CdS/PVA nanocomposites using gamma radiation

Films of poly(vinyl alcohol)/cadmium sulphide (PVA/CdS) nanocomposite containing various concentrations of Cd²⁺ ions were prepared using gamma radiation at different doses from 50 up to 200 kGy. The UV/VIS spectra revealed that the CdS/PVA nanocomposites showed blue shift for the absorption peak as compared with bulk CdS. As the irradiation dose increased, a gradual red shift in the wavelength accompanying with broadening of the absorption peak was observed. The estimated optical band gap energies and the calculated CdS particle sizes of (PVA/CdS) showed correlation between their values and the variable parameters (irradiation dose and Cd⁺²:S^?2 molar ratio). Transmission electron microscopy images showed that the CdS/PVA nanocomposites were dispersed as spherical CdS nanoparticles with homogeneity at either lower concentration of CdCl₂ or irradiation dose. The nano‐rod structures of CdS was accompanied with small agglomeration at either higher CdCl₂ concentration or irradiation dose. A cubic phase and mixture of cubic and hexagonal phases of the prepared CdS nanoparticles were formed at lower and higher CdCl₂ concentrations, respectively. Fourier Transform Infrared spectra confirmed the coordination of CdS nanoparticles with the hydroxyl groups of PVA matrix. POLYM. ENG. SCI., 55:2583–2590, 2015. © 2015 Society of Plastics Engineers     

Compositions,sources, and ecological risk assessment of poly-aromatic hydrocarbons in surface sediments along the Suez Gulf,Egypt

Poly-aromatic hydrocarbons (PAHs) were analyzed in sediments collected from the Suez Gulf to evaluate the composition, sources, and ecological risk assessment. The highest concentration of total PAHs is recorded in sediments collected from Inlet of Suez Oil Petroleum Company (SOPC), followed by east of the Outlet of SOPC and Outlet of SOPC. While lower concentrations of total PAHs are detected in Suez Beach west of the Outlet of SOPC, from Inlet of Al-Nasr Petroleum Company (NPC). The ratio of ∑LPAHs/∑HPAHs was <1, revealing their pyrogenic sources. The concentration levels of PAHs in the current study were compared to the effect range low (ERL) and the effect range medium (ERM) values for all investigated stations was below the ERL except for Inlet of SOPC. This finding indicated that PAHs in the surface sediments of the studied area have adverse biological effects, which may cause severe adverse biological and acute effects. The high levels of BaP equivalent (BaPE) values east of the Outlet of SOPC indicate that PAHs have relatively high toxicity among all sites. The toxic equivalent (TEQcarc) values of the sediment samples varied from 0.1883 to 1449.286 ng/g TEQ, with the mean value of 144.295 ng/g TEQ; the higher total TEQcarc values were found at 50 m east of the Outlet of SOPC: 1449.286 ng/g TEQ.     

Significance of GC/FT-IR and GC/MS in recognizing the sources of organic materials from sediments along the Suez Gulf Shoreline,Egypt

The present work aims to using the application of GC, GC/MS, UV, and FT/IR spectroscopy organic matters extracted from sedimentary hydrocarbons from six coastal stations located in the Gulf of Suez and proposed to evaluate hydrocarbons in the sediments. The results the origins of hydrocarbons are multiple sources from terrestrial inputs, biogenic, and pyrolytic. Abundance of vascular plant n C₂₃– n C₃₃ alkanes with a high odd-to-even predominance, pristane, and phytane beside nC₂₉/nC₁₇ ratios and the presence of biogenic hopanes indicate the predominance of biogenic in combination with petrogenic hydrocarbons. FT-IR spectroscopic analysis indicates high concentrations of aliphatic hydrocarbons as well as mono- and polynuclear aromatic hydrocarbons are useful tool in organic geochemistry studies. UV analysis for organic matters incorporated in sediments reveals that oil pollutants have considerable amounts of aromatic compounds.     

Modeling Groundwater Flow and Seawater Intrusion in the Coastal Aquifer of Wadi Ham,UAE

Groundwater pumping from Kalbha and Fujairah coastal aquifer of the United Arab Emirates (UAE) has increased significantly during the last two decades to meet the agriculture water demands. Due to the lack of natural replenishment from rainfall and the excessive pumping, groundwater levels have declined significantly causing an intrusion of seawater in the coastal aquifer of Wadi Ham. As a result, many pumping wells in the coastal zone have been terminated and a number of farms have been abandoned. In this paper, MODFLOW was used to simulate the groundwater flow and assess the seawater intrusion in the coastal aquifer of Wadi Ham. The model was calibrated against a five-year dataset of historical groundwater levels and validated against another eleven-year dataset. The effects of pumping on groundwater levels and seawater intrusion were investigated. Results showed that reducing the pumping from Khalbha well field will help to reduce the seawater intrusion into the southeastern part of the aquifer. Under the current groundwater pumping rates, the seawater will continue to migrate inland.     

Evaluation of petroleum hydrocarbons and its impact on organic matters of living organisms in the northwestern Gulf of Suez,Egypt

Abstract

The levels of Total Petroleum Hydrocarbons (TPH) have been reported for ten commercially important fish species from the northwestern Gulf of Suez, Egypt. Target compounds were analytically determined with gas chromatography–flame ionization detector and High-performance liquid chromatography analysis. Results showed that total petroleum hydrocarbon varied from 21700 to 1503100?ng/g wet wt., Argyrops Spinifer showed the highest level of TPH in the muscle tissue followed by Euthynnus affinis 1459800?ng/g wet wt. These data are very important for coming pollution monitoring program to the Suez Gulf. Polycyclic aromatic hydrocarbons (16 PAHs) varied between 81.499 and 5895.608?ng/g wet wt. The diagnostic indices used showed that the hydrocarbons in the area were from both biogenic and anthropogenic sources. Hence, there is need for adequate regulation and control of all activities contributing to the levels of petroleum hydrocarbon in the marine environment for the safety of human, and fish species lives in the area.