A Case Study to Evaluate the Role of Basiluses in Producing Biosurfactant and the Feasibility of MEOR

Bibi Hakimeh oilfield consists of more than 145 oil producing wells. Its Oligomiocene Asmari reservoir is dominantly made of limestone. The act of a reverse fault on the north flank of Bibi-Hakimeh Field caused a significant thickness reduction in Gachsaran formation in the way that in some drilled wells, members No. 2, 3, 4, 5 and 6 of Gachsaran cap rock have been totally eliminated. This causes locating Asmari reservoir in a shallower level and therefore lowers reservoir temperature in the North flank already have made the reservoir suitable for a microbiological enhanced recovery. The long term production of this reservoir caused a significant reservoir pressure drop. Therefore; the recovery has been performed using Basilus with Ex-Situ method. In this case study, the feasibility of surfactant production in several oil wells has been accomplished. A high temperature resistant Basilus has been selected to evaluate the production ability of biosurfactant. This bacterium has been chosen after performing all morphological, biochemical and genetic studies. This bacteria shows a good resistance against the temperature in such manner that its emulsification, surface tension and inter surface tension abilities do not change after 15 min in an autoclave process at 120° C. In the next step, the temperature, pH, Carbon, N2 and other factors have been optimized for biosurfactant                                     production. Considering the lithology of the reservoir using this type of bacterium. This can be a good way to produce lipopithidic biosurfactant by Ex-Situ method in Asmari to enhance oil recovery. The basilus, which has good resistance against temperature and acts well in pressurized environments, can be considered as a good candidate for tertiary enhanced oil recovery process. The best method to produce basilus in B5 is the Formislink method

Evaluation of corneal higher order aberrations in normal topographic patterns

Purpose: This study reports the characteristics of corneal higher order aberrations (HOAs) in eyes with normal topographic pattern using the Pentacam scheimpflug system. Methods: In this prospective, observational, comparative study, 165 eyes of 97 patients separated into five groups based on corneal topographic patterns were enrolled. All eyes received a comprehensive ophthalmologic examination including corneal tomographic analysis with the Pentacam system. Keratometry, corneal cylinder, and corneal aberrometric data were recorded and analyzed. Root mean square values (RMS) were calculated for corneal HOAs up to the 6th order, total coma, total trefoil, total spherical aberration, total tetrafoil, and higher order astigmatism. Evaluation of these data to discriminate between the five groups was assessed using the analysis of variance test by Generalized Estimation Equation Linear Model. Results: Corneal HOAs were found to be significantly higher for Asymmetric Bow Tie and Irregular groups than other groups (p = <0.001). RMS of total coma aberration (Z3-1, Z31, Z5-1, Z51) were significantly greater in the Asymmetric Bow Tie pattern than others, and RMS of total Spherical aberration (Z40, Z60) was significantly higher in the Irregular pattern than other groups (p = <0.001). The results of our study demonstrate that a tendency toward significant higher values of trefoil, tetrafoil, and higher order astigmatism in Irregular pattern (all p < 0.05). Significantly higher amounts of 3rd order RMS in Asymmetric Bow Tie group and 4th to 6th order RMS in Irregular pattern group were other outcomes of our study (p = <0.001). Conclusions: Based on results in this study, there were a good correlation between corneal topographic pattern and corneal HOAs in normal eyes. These results indicate that the corneal HOAs values are largely determined by the topographic patterns. A larger sample size would perhaps have been beneficial to yield in more accurate outcomes. © 2016 Iranian Society of Ophthalmology

Application of semi-rigid composite permeable pavements in road network

Use of Permeable Paving Systems (PPS) in road transport networks has been gaining more attention due to benefits such as minimising surface run-off, decreasing the risk of flash flooding and reducing pollutants deposited in waterways. Simultaneously the increasing stockpiles of waste tyre and its non-biodegradable nature leading to negative environmental impacts and associated hazards have posed increased attention to seek innovative sustainable solutions for reducing tyre stockpiles. Crumb rubber has enhanced properties that allow it to be a suitable substitution for rock aggregate in PPS. By using mixtures of tyre and rock aggregates and engineered level of binders the flexibility of PPS can be optimized based on the application to accommodate differential settlements thus reducing degradation and cracking commonly observed in conventional permeable pavement systems. This can ultimately lead to an increase in serviceability and minimising costly maintenance works and more importantly expand the range of applications permeable pavements can be used in. This study reports on the mechanical behaviour of a range of semi-rigid PPS products incorporating tyre crumbs for surface paving with high drainage capability for mitigation of storm-water run-off. The transient stiffness-deformation behaviour of a range of permeable pavement systems with varying tyre crumb content and binder type under variable loadings was investigated. In the first step, different mixing ratios of crushed rocks (rigid aggregate) and tyre crumbs (soft aggregate) were tested in the laboratory to find the optimum mixtures fit for different applications. Constraint modulus and shear wave velocity tests were carried out to establish the mixtures which their performance changes from rigid-type to soft-type with varying pressure level. Results of this step provide an insight into the formation of force chains in the mixtures ultimately providing the most formidable mix ratio resulting in transitional soft to rigid behaviour. In the next step different binder types (polyurethane based) and percentages were added to selected blends to investigate the performance of polymer bonded tyre-rock aggregates under static and dynamic loads. Test results suggest that the quality of binder only shows its impact for tyre contents higher than 30%. In blends with higher tyre contents the force chains mostly pass through tyre aggregates and hence the deformation of tyre aggregates puts more strain on binder film causing the lower grade binders to fail. Same low grade binders show satisfactory results when tested with mixtures up to 30% tyre content. Preliminary test results suggest that the optimum mixture of tyre and rock aggregate with the right binder type and ratio can produce a permeable pavement system suitable for car parks and other lightly trafficked areas including pedestrian footpaths

Flexural beam fatigue strength evaluation of crushed brick as a supplementary material in cement stabilized recycled concrete aggregates

In recent years, efforts have been made by various researchers to explore the sustainable use of Construction and Demolition (C&D) materials as a construction material in civil engineering applications. Recycled crushed brick is a commonly found material from demolition activities and works to date on this material in pavement applications have been limited to its usage in unbound pavement layers. This research was undertaken to evaluate the performance of crushed brick as a supplementary material in cement stabilized recycled concrete aggregates. An extensive suite of tests were undertaken on the crushed brick and recycled concrete aggregate blends stabilized with 3% cement. The laboratory evaluation comprised pH, plasticity index, foreign materials content, particle size distribution, linear shrinkage, California Bearing Ratio, modified Proctor compaction, Repeated Load Triaxial test, Unconfined Compressive Strength Test and Flexural Beam Tests. The cement stabilized blends with up to 50% crushed brick content and 3% cement were found to have physical properties, which comply with the local state road authority requirements. The results of Repeated Load Triaxial tests indicated the Recycled Crushed Aggregate/Crushed Brick (RCA/CB) blends performed well with 50% Crushed Brick (CB) content just on the border line for bound pavement material. Unconfined Compression Strengths met the minimum requirement for 7 days of curing for all blends, while the 28 day strength of the blends also improved significantly. The results of the flexural beam tests were noted to be consistent with past works with cement stabilized quarry produced crushed rock products. The modulus of rupture and flexural modulus for all the cement-stabilized blends were found to be consistent with the previous works, which indicate that these blends are suitable for applications such as cement-stabilized pavement subbases. The fatigue life was also within the range that has been previously reported for quarry materials. The cement-stabilized blends with crushed brick as a supplementary material with up to 50% brick content and 3% cement were found to have physical and strength properties, which would comply with road authority requirements

A qualitative exploration of the factors associated with initiation to methamphetamine use in Iran

Background: Crystal (methamphetamine) is a strong stimulant of addictive substances that affects the central nervous system. The consumption of this substance is increasing among teenagers and adult young people in the country. In this matter, one of the practical and important ways to its control is to identify the factors leading to its first use. Thus this paper, explores the factors related to the first crystal use in Golestan province, Iran. Methods: In a qualitative study, 19 crystal users were recruited in the study conducted in Golestan province by snowball sampling from DIC (Drop-In Center) in addiction treatment centers. The interviews were mostly carried out individually with the participants; only one interview was conducted in an addiction treatment camp in the form of a group-focused discussion. Data analysis was implemented through content analysis in MAXQDA 10 software. Results: The mean age of the participants was 35.05 ± 6.06 years with a range of 23�46 years. Meanwhile, the mean of crystal use period was 7.42 (SD: 3.61) and a range of 1�14 years. Based on the obtained data, the reasons for first crystal use could be categorized in six; 1: �crystal use to other drugs rehabilitation�; 2: �Lack of awareness of the addictive nature of crystal�; 3: �stimulating curiosity in public with crystal-use friends�, 4: affordable and convenient use�, 5: �anti-sleeping effects and increasing work efficiency�, and 6: �therapeutic and other misconceptions��. Conclusions: The results indicated that crystal is mostly abused to opium rehabilitation. The lack of awareness and misconceptions about this substance can lead people to crystal use. Therefore, designing public health interventions to increase awareness about negative consequences of crystal use is fundamental to prevent people from abusing it. We suggest designing public health program to promote awareness about health risks of crystal and modifying related misconceptions. Finally, the government can establish policies to mandate sale tax for crystal producers and reduce easy access to crystal especially among youth. © 2020, The Author(s)