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Abstract Unconventional resources, such as heavy oil, are increasingly being explored and exploited due to the declining availability of conventional petroleum resources. Heavy crude oil poses challenges in production, transportation, and refining, due to its high viscosity, low API gravity, and elevated sulfur and metal content. Improving the quality of heavy oil can be achieved through the application of steam injection, which lowers the oil’s viscosity and enhances its flow. However, steam injection alone falls short of meeting the growing demand for higher-quality petroleum products. Catalytic upgrading is therefore being investigated as a viable solution to improve heavy oil quality. This study experimentally investigates the application of two novel catalysts, namely copper-substituted zinc ferrite (ZCFO) synthesized via the sol–gel combustion method and a graphene oxide-based nanocomposite (GO-ZCFO) with different ratios, for catalyzing aquathermolysis reactions in the steam injection process, with the aim of enhancing the in-situ upgrading of heavy oil. These catalysts underwent characterization using X-ray powder diffraction (XRD), Fourier Transform Infrared Spectroscopy (FTIR), and Transmission Electron Microscopy (TEM). Their catalytic performance was assessed utilizing a high-pressure/high-temperature reactor (300 ml), with a comprehensive analysis of the changes in the physical and chemical properties of the heavy oil before and after upgrading. This analysis included measurements of sulfur content, SARA fractions, viscosity, API gravity, and Gas Chromatography (GC) of saturated hydrocarbons and evolved gases. All upgrading experiments, including both catalytic and non-catalytic aquathermolysis processes, were conducted under a reaction time of 6 h, a reaction temperature of 320 °C, and high pressure (86–112 bar). The results indicated that the introduction of the proposed catalysts as additives into the upgrading system resulted in a significant reduction in sulfur content. This, in turn, led to a decrease in resin and asphaltene content, an increase in the content of saturated hydrocarbon, particularly low-molecular-weight alkanes, and ultimately, a reduction in viscosity along with higher API gravity of the crude oil. GO-ZCFO with a weight ratio (50:50) exhibited the best catalytic performance. The heavy crude oil, upgraded with this 50:50 ratio, exhibited significant enhancements, including a 29.26% reduction in sulfur content, a 21.27% decrease in resin content, a 37.60% decrease in asphaltene content, a 46.92% increase in saturated hydrocarbon content, a 66.48% reduction in viscosity, and a 25.49% increase in API gravity. In comparison, the oil upgraded through non-catalytic aquathermolysis showed only marginal improvements, with slight reductions in sulfur content by 5.41%, resin content by 3.60%, asphaltene content by 11.36%, viscosity by 17.89%, and inconsiderable increases in saturated hydrocarbon content by 9.9% and API gravity by 3.02%. The GO-ZCFO, with its high catalytic activity, stands as a promising catalyst that contributes to improving the in-situ upgrading and thermal conversion of heavy crude oil.

Purpose: To evaluate inlay and onlay marginal adapta2on of two different ceramic materials using two intracoronal prepara2on designs. Materials and Methods: An examina2on of the marginal adap2on of two materials--lithium disilicate (LD; IPS e.max CAD) and polymer infiltrated ceramic network material (PICN; Vita Enamic)--and two prepara2on designs, where D1 represents MOD inlay prepara2on with no cusp reduc2on and for D2, in addi2on to the basic MOD prepara2on, the buccal cusps (func2onal cusps) were reduced by 1.5 mm. Four sub-groups (LD-D1, LD-D2, PICN-D1, PICN-D2) were conducted. In total, 40 (n = 40) mandibular molars were used. A stereomicroscope was used to assess the marginal gap before, aWer cementa2on and aWer thermocycling. Values were calculated for the mean, median, SD, minimum, maximum, and 95% CI. Pairwise comparisons using Tukey post-hoc test were performed following an ANOVA significance of P = .05. Results: The results revealed that lithium disilicate showed sta2s2cally significantly higher mean gap distance than PICN material (61 µm to 99 µm). Pairwise comparisons showed that D2 design has sta2s2cally significant higher mean gap values than D1. Conclusions: Both LD and PICN material provided marginal adapta2on within clinical accepted range. PICN material restora2ons provided beer fit than lithium disilicate restora2ons. Cusp coverage has a greater marginal gap compared to conven2onal prepara2on. [ABSTRACT FROM AUTHOR]

The accelerated urbanization in the last decade and population growth in developing countries in the Middle East and North Africa (MENA) region have increased the count of humans exposed to air pollution. This work aims to provide an insight into air quality in the Greater Cairo (GC) area which is one of the largest megacities in the MENA region and is classified as its most polluted city according to the reports of the World Health Organization (WHO). Exploratory data analysis and cluster analysis were used to assess the pollutants data and meteorological data to understand the impacts of weather factors on air quality in GC. According to the results, GC suffers from particle matter of 10 micrometres or less (PM10) pollutants. The annual averages ranged from 97 ± 10 to 203 ± 42 μg/m3. Though short-term exposure to gaseous pollutants did not exceed the limits, the long-term exposures exceeded those in some congested traffic areas. The annual averages ranged from 20 ± 5 to 63 ± 24 μg/m3 for Nitrogen dioxide (NO2) and from 9 ± 3 to 21 ± 5 μg/m3 for sulphur dioxide (SO2). Also, the terrain affects the spatial variation of pollutants observation. There is a negative correlation between the monitoring site elevation and the pollutant concentration.

Understanding the phase behavior and volumetric changes of reservoir fluids throughout the extent of reservoir lifetime are crucially required for effective-commercial oil recoveries. Ideally, reservoir fluid properties are experimentally measured by laboratory experiments known as PVT tests nonetheless, these tests are prohibitive, time-consuming, and required to restrict sampling and transporting procedures. For these discernible reasons, several modeling approaches have been developed. By reviewing the literature, one crucial obstacle that encounters field applicability of most extant models is the selection of input variables. Moreover, a great percentage of extant models employ the results of lengthy experimental tests such as differential gas solubility or even the sample’s chemical composition. Replicability of models’ results using different datasets is also one of the main challenges when employing AI models. Frequently, inadequate descriptions for AI models have been provided in many studies which limits their utility. The inadequate description includes the analysis of ANN model weights and biases besides, the final mathematical model. In this study, a rigorous ANN model with its mathematical model has been implemented to predict oil formation volume factors based on 600 compiled datasets from Egyptian oilfields.A detailed comparison between widely used empirical correlations and the proposed new ANN model is provided in this study. Statistical and graphical analysis depicted the outstanding performance of the new model with R2 = 0.974, ARE = −0.0017%, and AARE = 2.13%. The ANN model provides remarkable sustainable performance compared to local Egyptian empirical correlations and all the other global models.

Abstract A muon collider would enable the big jump ahead in energy reach that is needed for a fruitful exploration of fundamental interactions. The challenges of producing muon collisions at high luminosity and 10 TeV centre of mass energy are being investigated by the recently-formed International Muon Collider Collaboration. This Review summarises the status and the recent advances on muon colliders design, physics and detector studies. The aim is to provide a global perspective of the field and to outline directions for future work.

The interaction between thermal discomfort and air pollution poses significant challenges for human health and environmental well-being. When there is a high level of air pollution, it can worsen thermal discomfort by trapping heat in the atmosphere. This paper aims to study this interaction in arid megacities during different weather events. Weather data and air pollution were utilized to evaluate air quality, thermal discomfort levels, their impact, and their relationship at three separate sites (Qaha, Naser City, and 6th of October City). The ambient air quality is determined by measuring the levels of particulate matter (PM10), nitrogen dioxide (NO2), and sulfur dioxide (SO2). The work included a statistical analysis of the discomfort index (DI) and the air quality index (AQI) for each city and their linkage with the weather. The air quality evaluation revealed that a significant portion of the population in Qaha frequently experienced discomfort and were exposed to unhealthy levels of air pollution. The results show that most of the population in all three cities experience discomfort at least some of the time with varying degrees. In Qaha, 28.97% of the population experiences no discomfort, while 25.41% experiences severe stress. In Nasr City, 32.15% of the population experiences no discomfort, while 20.21% experiences severe stress. The 6th of October City, 33.76% of the population experienced no discomfort, while 16.65% experienced severe stress. Noted that certain months, specifically June to September, are associated with higher levels of discomfort, affecting more than 50% of the population. Seasonal variations in discomfort can be due to a range of factors, including weather, climate, and environmental conditions. The temporal variation in discomfort reflects the challenges people face when transitioning from colder to hotter seasons.

The multiplicity distribution of charged particles produced from proton–proton collisions at energies s = 2.36, 2.76, 5, 7, 8, 10, 13 and 14 TeV were studied in the present work. Furthermore, multiplicity distribution was studied in different pseudorapidity regions ∣η∣ < 0.5, 1, 1.5, 2, and 2.5. KNO scaling was studied at the same pseudorapidity regions. This is valid in the pseudorapidity region ∣η∣ < 0.5, but with increasing pseudorapidity, the violation increases. The influence of MPI and color reconnection in violation of KNO scaling were studied. The relation between mean multiplicity and collisions energy was explored, noted that it increases with the increasing energy of collisions.

Background: Two intra‐coronal preparation designs with varying extensions of cuspal coverage can perform differently regarding their fracture resistance against introral forces. Methods: Two materials (IPS e‐max CAD [EX], VITA ENAMIC [EN]), and two different preparation designs (EX‐D1), (EX‐D2), (EN‐D1), and (EN‐D2) were investigated to compare their fracture resistance. A total of 40 (n = 40) caries free human mandibular molars were used. All the prepared samples were scanned using CEREC Omnicam scanner and the preparations were checked by the software for any sharpness and undercuts before restoration designing and fabrication. All restorations were milled using Cerec MCXL 4.4 milling machine. Duo‐Link resin cement was used for cementation. After thermocycling and chewing simulation, all samples were loaded in the Universal testing machine in order to evaluate fracture resistance of all samples. Results: Fracture resistance testing revealed that e‐max CAD (2134 N) showed statistically significantly higher mean fracture resistance values than Vita Enamic (1728 N). On the other hand, there was no statistically significant difference between mean fracture resistances between the two tested designs. Conclusions: Within the confines of this investigation, it can be said that although preparation design had no appreciable impact on fracture resistance, the CAD/CAM ceramic material utilized did. Clinical Significance: When restoring compound cavitties indirectly; a conservative defect oriented approach should be used. Glass Ceramic are prefered as restorative material. [ABSTRACT FROM AUTHOR]

Heat stress is a substantial environmental challenge that adversely affect health and performance. This study aimed to investigate the effect of advanced short-term dietary supplementation of probiotics or vitamin C on serum biochemical parameters, antioxidant status, and radiographic bone density in heat-stressed rats. A 48 male albino rat were randomly allocated into six groups: Control, Heat stress, Probiotics, Probiotics+Heat stress, Vitamin C, Vitamin C+Heat stress group. Rats in supplementation groups received probiotics or ascorbic acid orally from week 1 to 8. Heat stress groups were subjected to elevated temperature (42±1 °C and relative humidity 65±2%) 60 minutes daily for 4 weeks starting from week 5 to 8, while other groups were maintained under standard laboratory conditions. Heat stress resulted in increased serum ALT, AST, urea and creatinine (P<0.001), decreased calcium, increased phosphorus and osteocalcin (P<0.001), increased serum MDA, decreased TAC (P<0.001), decreased radiographic bone density (P<0.001) compared to other groups. Histopathological examination of liver, kidney and adrenal glands reflected the ongoing heat-stress damage. Administration of probiotics and ascorbic acid demonstrated substantial protection, suggesting their potential efficacy against heat stress. The obtained findings hold promise for the development of novel strategies to enhance heat stress resilience in animals. [ABSTRACT FROM AUTHOR]