Multivariate statistical analysis for monitoring the hydrocarbon potentiality of the source rocks in the North Western Desert,Egypt

The authors aimed to examine a multivariate statistical analysis approach for monitoring the hydrocarbon potentiality of source rocks in the North Western Desert to recognize the potentiality of source rocks and subsequently investigate the maturation level of the proven potential source formations for oil preservation. To achieve this aim, they applied multivariate statistics analysis (principle component analysis [PCA], cluster analysis, and correlation coefficient) and Rock-Eval pyrolysis analyses. The results showed that both PCA and cluster analyses have showed two types of source rocks. The first is classified as poor to fair source rock and immature to marginally mature source rock, the second is considered as fair to good source rock and mature to post mature source rock. PCA extracted two independent factors, which explained 81.87% of the total variance. The first type of source rock was responsible for 50% of the total variance and was best represented by variables TOC, S2, OI, and R_o, and the second one was responsible for 31.65% of the total variance and was represented by the HI variable. Pearson correlation coefficient showed a significant positive correlation between TOC and S2 or R_o. A positive correlation between S2 and HI or OI and also between OI and R_o was observed, while no significant correlation was noticed between HI and R_o.     

More IMPATIENT: A gridding-accelerated Toeplitz-based strategy for non-Cartesian high-resolution 3D MRI on GPUs

Several recent methods have been proposed to obtain significant speed-ups in MRI image reconstruction by leveraging the computational power of GPUs. Previously, we implemented a GPU-based image reconstruction technique called the Illinois Massively Parallel Acquisition Toolkit for Image reconstruction with ENhanced Throughput in MRI (IMPATIENT MRI) for reconstructing data collected along arbitrary 3D trajectories. In this paper, we improve IMPATIENT by removing computational bottlenecks by using a gridding approach to accelerate the computation of various data structures needed by the previous routine. Further, we enhance the routine with capabilities for off-resonance correction and multi-sensor parallel imaging reconstruction. Through implementation of optimized gridding into our iterative reconstruction scheme, speed-ups of more than a factor of 200 are provided in the improved GPU implementation compared to the previous accelerated GPU code.     

Prospective and retrospective reports of mood states before relapse to substance use.

In a prospective design, it was predicted that the role of negative mood in precipitating relapses and crises among alcohol-dependent Ss would be greater when assessed with retrospective mood ratings than when assessed by prospective mood ratings because of Ss' attributional biases. This hypothesis was not supported. Support was found, however, for a relationship between negative bias and the amount of negative mood assessed at the time the retrospective report was given. As has been previously found, the most frequent precipitant of relapses and crises in this study was negative emotional states. Female Ss were more likely to report interpersonal and less likely to report intrapersonal determinants than male Ss. Minor relapses were more likely to be precipitated by social pressure and less likely to be related to negative emotions than major relapses. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Oil:Oil Correlation for Some Oil Fields in the North Western Part of the Western Desert, Egypt

Physical and specific geochemical analyses are used in detail for the petroleum geochemical studies to permit the correlation of six crude oil samples from Western Desert Egypt. Different analytical techniques, including liquid chromatographic separation, gas chromatography, and gas chromatography-mass spectrometry (GC-MS), were used to characterize the oil samples. The oils were identified using oil characterization parameters including specific gravity (°API), sulfur content, distribution of n-alkanes, carbon preference index (CPI), pristane/phytane ratio, isoprenoid/n-alkane ratios, and detailed biological marker analysis. All these parameters showed that the studied oil samples are correlated with each other, where they are similar in their oil type maturation and source depositional environments.     

Electrochemical determination of niobium cathode as an efficient electrocatalyst for hydrogen generation in acidic media

Hydrogen gas (H₂) is notified as a renewable energy carrier. It is wanted to discover a low-cost electrocatalyst for the hydrogen evolution reaction (HER) to substitute the high-cost Pt in electrolysis cell. Niobium electrocatalyst nominated to substitute noble materials for electrocatalytic H₂ production and its electrochemical manner was estimated in H₂SO₄ acid of various concentrations utilizing a steady-state polarization and electrochemical impedance spectroscopy (EIS). The influences of acid concentration, cathodic potential and temperature on the H₂ creation were examined. The outcomes display that HER on Nb electrode proceeds by the Volmer-Heyrovsky mechanism. EIS tests, under open circuit and under cathodic polarization, were performed and the fitting has been done utilizing a suggested model for the electrode/electrolyte interface. Apparent activation energies (E_a) were estimated to be ca. 10.5 kJ mol^?1 for the HER on Nb. Thus, Nb is a good electrocatalyst for the cathodic H₂ manufacturing.     

Source rock potentiality of Middle Jurassic–Lower Cretaceous of wells,North Western Desert,Egypt

The source rock potentiality of Middle Jurassic–Lower Cretaceous source rocks in Meleiha area was investigated through total organic carbon (TOC), R_o%, and pyrolysis analysis for 38 cutting samples collected from six wells. Also, the geochemical burial history profile to estimate the timing of hydrocarbon generation and expulsion of source rocks was constructed. The result revealed that the main hydrocarbon of source rocks, for the Middle Jurassic (Khatatba Fm.), is mainly mature, and has good capability for producing oil till present time. Lower Cretaceous source rocks (Alam El Bueib Fm.) are mature, derived from mixed organic sources, and have fair to good capability to generate gas and oil. Kharita Formations immature source rocks originating from terrestrial origin and have poor to fair potential to produce gas.     

Passively Q-switched erbium-doped fibre laser using cobalt oxide nanocubes as a saturable absorber

We demonstrate a Q-switched Erbium-doped fibre laser (EDFL) utilizing cobalt oxide (Co₃O₄) nanocubes film based saturable absorber (SA) as a passive Q-switcher. Co₃O₄ nanocubes are embedded into a polyethylene oxide film to produce a high nonlinear optical response, which is useful for SA application. It has saturation intensity and modulation depth of 3 MW/cm² and 0.35%, respectively. The proposed laser cavity successfully generates a stable pulse train where the pulse repetition rate is tunable from 29.8 to 70.92 kHz and the pulse-width reduces from 10.9 to 5.02 μs as the 980 nm pump power increases. This result indicates that the Co₃O₄ is excellent for constructing an SA that can be used in producing a passively Q-switched fibre laser operating at a low pump intensity. To the best of our knowledge, this is the first demonstration of Co₃O₄ film based fibre laser.     

Oil: Source rock correlations of Al Baraka oil field,Komombo basin,South Egypt: An implication from biomarkers characteristics

The objectives of this study are the correlation between the oil samples recovered from the Lower Cretaceous reservoirs and Lower and Upper Cretaceous source rocks. The investigated biomarkers of five oils indicated the oils were derived from mixed marine and terrigenous (lacustrine) organic matter and deposited under suboxic to anoxic conditions. These oils were also generated from source rocks of high thermal maturity at the peak oil window. So, based on the molecular indicators of organic source input,depositional environment and maturity parameters of oils and extracts, we can conclude that the oil recovered from Al Baraka oil field were derived from Lower Cretaceous source rocks especially KomOmbo (B) source rocks where it reached the oil window. Furthermore, we can indicate that the other lower Cretaceous formations as Abu Ballas Formation will have the opportunity to generate and expel oil at the deeper part of the basin as shown in the eastern part of the basin.     

Electroplated Zn–Ni nanocrystalline alloys as an efficient electrocatalyst cathode for the generation of hydrogen fuel in acid medium

Energy conversion and renewable energy are the valuable research fields for the future of the energy. Synthesis of electroplated thin film of low cost elements and their alloys is promising nanomaterials for energy conversion. Electroplating of Zn–Ni alloys were performed using natural products such as cysteine and gluconate under direct current and ultrasound waves. The morphological and crystalline structures of the electroplated Zn–Ni alloys were examined using scanning electron microscopy, SEM, and X-ray diffraction techniques, XRD. The chemical composition of the electroplated Zn–Ni alloys was determined using energy dispersive X-ray analysis, EDX. The morphological structures of electroplated Zn–Ni alloys changed from smooth to coral reef-like and granular structures with the increase of Zn wt%. Electrocatalysis of the hydrogen evolution reaction using the electroplated Zn–Ni alloys was studied in 0.5 M H₂SO₄ medium by the cathodic polarization and electrochemical impedance spectroscopy, EIS. The electroplated Zn–9.5Ni cathode of cubic γ-brass arrangement exhibits the highest rate of hydrogen evolution reaction.     

Effective treatment for environmental enhancing the performance of undesirable agro-waste in production of carbon nanostructures as adsorbent

The work in this article deals with enhancing the performance of rice straw (RS) for production of carbon nanostructures (CNSs), as aqueous phase adsorbents, as well as benefit solution for disposing of this undesirable waste and for avoiding the environmental risk from burning. In this respect, controlling the constituents of RS by enzymatic treatment, followed by hydrothermal treatment and carbonization was carried out. The benefit role of the performed treatments was supported via comparing these CNSs with those obtained from RS pretreated by chemical pulping processes; moreover, literature reported CNSs. Results deduced from SEM and TEM analyses showing that, the two investigated CNSs samples have different surface morphologies and comprised of graphitic carbons as nodules and multi-layer graphene sheets. The investigated RS-based CNSs own numerous of oxygen-containing functional groups with low specific surface area and high mesopore volume; thus, they exhibited high iodine number of 959 and 863 mg/g, respectively. The CNSs from hydrochar of peroxidase treated RS has higher uptake to methylene blue (MB) dye (358 mg/g) than that produced from hydrochar of cellulase treated RS (202 mg/g), this may be related to its unique nanostructure. Both values are higher than that of reported CNSs, which obtained from chemical pulping processes (~ 54–119 mg/g). The adsorption of MB dye is well-fitted with Langmuir and described by pseudo-second order kinetic model.