Rheology of modified binders under varying doses of WMA additive–Sasobit

Use of warm mix asphalt (WMA) technology to reduce construction temperatures of asphalt mix has gained strong interest worldwide. However, the technology is still in its inception stage in India. Present study evaluated the rheological properties of polymer- and crumb rubber-modified bitumen with various doses of WMA additive Sasobit (1%, 2%, and 3% by binder weight). Frequency sweep and temperature sweep results showed that increase in Sasobit content improved elastic properties of binders. Creep, repeated creep recovery, and multiple stress creep recovery results showed better resistance toward permanent deformation for Sasobit-modified binders in comparison to control binders.     

Thermal degradation of synthetic lubricating oils: Part II – Rheological study

The characterization of thermal degradation process of synthetic lubricating oils, in relation to its rheological properties, was evaluated in this work. Analyses of the dependence of synthetic lubricant viscosity on temperature have been carried out. Synthetic lubricants were degraded at different temperatures and times, in air atmosphere. After thermal degradation, synthetic lubricant oils were characterized by rheological measurements. In general, the increase in degradation temperature led to an increase of the lubricants viscosity for some lubricant samples.     

On predicting properties of explosives – detonation velocity

Abstract

A systematic method of representing an explosive, based on its composition, is presented. This method is used to display performance data for existing explosives, and suggests an alternate definition for oxygen balance and determines compositions that might produce high-performance explosives. A new method for predicting the detonation velocity of a proposed explosive is also presented. This is a simple method that also yields insight into which factors are important in predicting performance.     

Predicting PVT properties of Egyptian crude oils by a modified Soave–Redlich–Kowng equation of state

The study aims to predict the physical properties of Egyptian crude oils using modified Soave–Redlich–Kowng equation of state. The modification was theoretically developed and then performed by using data of 43 black oil samples representing all active oil producing areas of Egypt. The equation enables to predict the bubble-point pressure, oil formation volume factor, gas–oil ratio, oil density, crude oil gravity, gas gravity and gas formation volume factor of black oils with average relative errors ranging from 0.01% to 10.713%.Calculation sensitivity of the proposed MSRKE is determined by testing four oil samples collected from different locations in Egypt and comparing the measured PVT properties with those calculated from MSRKE. These evaluations show an excellent agreement between the measured properties and calculated ones.The estimation of reservoir liquid and gas properties from MSRKE is often needed when detailed laboratory PVT data are not available.     

Variation of the physicochemical properties diesel-biodiesel blends – range 0–100%

Recently biodiesel has become more attractive because it is made from renewable resources. In this study we demonstrate how the proportion of diesel/biodiesel blends determines the qualitative parameters and energy efficiency of the final product. The use of biodiesel in blends with conventional diesel is becoming more and more valuable, based on European directive for use up to 20% biodiesel by 2020. We came to the conclusion that mixtures up 30% Biodiesel gives product within diesel specification limits which is suitable for commercial use. This methodology can be a manual for the production line of mixtures for commercial use.     

Synthesis and properties of soluble poly（aryl ether sulfone ether ketone）s copolymers containing pendant methyl groups

A series of Poly（arly ether sulfone ether ketone）s containing pendant methyl groups were synthesized by the reaction of 4,4＇-[sulfonylbis （1,4-phenylene）dioxy] dibenzoyl chloride （SODBC） with 4,4＇- diphenoxy diphenylsulfone （DPODPS）, 4,4＇- di（2-methylphenoxy） diphenylsulfone （o-Me-DPODPS）, 4,4＇- di（3-methylphenoxy） diphenylsulfone （m-Me-DPODPS）, 4,4＇- di （2,6-bimethylphenoxy） biphenylsulfone（o-Me2-DPODPS） respectively, in a mixture of 1,2-dichloroethane （DCE） and N-methylpyrrolidone （NMP）. These reactions were catalyzed by anhydrous aluminum chloride （AlCl）. The characteristic of copolymers were studied by means of advanced analytical techniques such as FT-IR,1H-NMR, DSC, TGA and WAXD. The results show glass transition temperature （Tg） in the range of 193-206℃, thermally stable in excess of 434℃ and excellent solubility in polar solvents. Methyl-substituted Poly（aryl ether sulfone ketone）s had higher glass transition temperatures, lower initial decomposition temperatures than the unsubstituted ones.     

Droplet digital PCR for routine analysis of genetically modified foods (GMO) – A comparison with real-time quantitative PCR

Droplet digital polymerase chain reaction (ddPCR) has seen increasing applications in recent times, also in the analysis of genetically modified (GM) food and feed samples. While quantitative real-time PCR (qPCR) methods have been traditional mainstays till now, the applicability of ddPCR in routine analysis of GM food and feed has not yet been widely demonstrated. In this work, we applied ddPCR on selected GM-food and feed samples that were recently analyzed on the qPCR platform in inter-laboratory proficiency tests and showed good performance of the ddPCR method. Sometimes GM DNA at different transgene levels, useful as reference material is not readily available. Applying ddPCR, different concentrations of GM material, specifically transgene DNA at different levels (0.1–10%) useful as reference DNA, were generated from 100% non GM material and 100% transgene plant material respectively, and key performance parameters of the ddPCR assay evaluated. DdPCR performed well, indicating its suitability for the production of reference GM materials. In an expanded analysis, DNA extracted from a 100% GM reference soy plant (CV127) was appropriately diluted to low copy numbers and the absolute LOD_95% determined at 2 copies (nominal value), comparing well with various published qPCR assays. In our inhibition studies, ddPCR showed a clear advantage over qPCR in SDS-inhibited samples, while its tolerance to other tested inhibitors was comparable with qPCR. Significantly, the qPCR assays demonstrated more asymmetrical amplification/inhibition with EDTA as inhibitor, with unequal inhibition in reference and transgene reactions, while inhibition was more symmetrical on the ddPCR platform. Finally, a panel of positive reference material with varying GM content from 0.1 to 10% were evaluated on the ddPCR platform and pertinent performance parameters assessed, namely, precision, accuracy and trueness of results, with good performance of the assay.     

Rheological Evaluation and Modeling of Sasobit®-Modified Asphalt Binder at High Temperatures

Warm mix asphalt using Sasobit® (Sasol Wax Company, Sasolburg, South Africa) is a new technology to reduce construction temperatures of asphalt mixes. This article presents the rheological properties of Sasobit-modified asphalt binder at high temperatures using response surface methodology. The results showed that the temperature at which the asphalt binder was blended with Sasobit had no effect on the high-temperature properties of Sasobit-modified asphalt binder, including viscosity and viscosity–temperature susceptibility, at each aging state. All empirical viscosity and aging models of Sasobit-modified asphalt binder follow second-order polynomial trends with test temperature, Sasobit contents, and their interactions at each aging condition.     

Road bitumen's based on the vacuum residue of heavy oil and natural asphaltite: Part II – physical and mechanical properties

This work is devoted to studying the possibility of producing bitumen for road construction by using vacuum residue >420°C of heavy oil of the Ashal'chinskoe field in and natural asphaltite Spiridonovskoe field from Permian deposits in Tatarstan. The effect of natural asphaltite as a solid disperse phase element on the structural and group composition of the residual heavy oil product and its malacometrical qualities (penetration, extensibility, softening point, resistance to aging and adhesion) are revealed. Samples, compounded bitumen production, were carried out by introducing the required amount of the shredded asphaltite to deasphaltizat vacuum residue of heavy oil and heating their mixture to 220°С with vigorous stirring. Changes in the composition and physical and chemical properties of deasphalting the residual heavy oil product, associated with the amount of injected asphaltite, showed the possibility of production of modified bitumen with better adhesion properties that correspond to road bitumen.     

Rutting and moisture resistance evaluation of polyethylene wax–modified asphalt mixtures

One of the methods newly introduced in pavement technology to address environmental concerns and reduce total gas emission is warm mix asphalt (WMA) technology. In this study, polyethylene wax is used to produce WMA mixtures. Although this technology has several positive features, moisture and rutting resistance of WMA mixtures are always questionable. To evaluate moisture and rutting resistance of polyethylene-modified mixtures, indirect tensile strength and dynamic creep tests were used, respectively. Results indicated that polyethylene has positive effect at low compaction temperature on moisture resistance, and also has negative effect on rutting resistance.     

Hydrogenation of aromatic hydrocarbons over nickel–tungsten sulfide catalysts containing mesoporous aluminosilicates of different nature

The hydrogenation of naphthalene, toluene, and 2-methylnaphthalene used as model compounds; the hydrodearomatization of the methylnaphthalene fraction; and the hydrocracking of oil sludge over Ni–W sulfide catalysts supported on BEA/TUD, BEA/SBA-15, and ZSM-5/SBA-15 composites containing SBA-15 and TUD mesoporous silicates have been studied. Catalytic tests have been conducted in an autoclave at 300–400°C and an initial hydrogen pressure of 50–90 atm. It has been found that the highest activity is exhibited by the catalyst based on the ZSM-5/SBA-15 (1) composite prepared by the double-templating synthesis and characterized by a specific surface area of 400 m²/g and an acidity of 409 μmol/g. Thus, in the case of dearomatization of the methylnaphthalene fraction at 300°C and an H₂ pressure of 50 atm, the content of diaromatic compounds has decreased from 99.0 to 53.4%, while the amount of sulfur compounds has decreased almost 15-fold. The hydrocracking of oil sludge over NiW/ZSM-5/SBA-15 (2) at 400°C and an H₂ pressure of 90 atm has led to an increase in the content of light fractions to 52%.     

Preparation of an SBS Latex–Modified Bitumen Emulsion and Performance Assessment

Abstract

For resolving the contradiction of the stability between styrene-butadiene-styrene (SBS)-modified bitumen emulsion and the concentration of SBS, a method of preparing SBS latex is provided in this article. Results showed that SBS latex had good stability properties and performance. The effect of emulsifier concentration on the storage stability showed that the maximum stability of SBS latex–modified bitumen emulsion (SBS-LMBE) was obtained at emulsifier weight concentration 1.0% and addition of SBS latex to bitumen emulsion enhanced the difficulty of emulsification. The effects of SBS latex on bitumen properties showed the penetration decreased, whereas the softening point and ductility at 5°C increased, which means that SBS latex plays a role in improving the properties of bitumen. Compared to the base bitumen, saturate and aromatic of evaporation residue of SBS-LMBE decreased. However, resin and asphaltene increased. Analysis of the relationship between the components and properties of bitumen showed that the components change caused by SBS latex was beneficial to the properties of bitumen. The colloidal index (CI) showed that SBS latex also made the colloidal system more stable.     

Effect of styrene–butadiene–styrene copolymer modification on properties of Saudi bitumen

This research investigates the effects of styrene-butadiene-styrene (SBS) copolymer and other plastomers on the behavior of Saudi bitumen. Three bitumen samples, extracted from three Saudi oil refineries, namely Ras Tanura, Riyadh, and Yanbu, were used in this study. The bitumen samples were mixed with different modifiers in various compositions, forming polymer modified bitumens (PMBs). Elasticity parameters, such as ductility and elastic recovery were measured and evaluated. Characteristics of raw bitumen were analyzed to observe the compatibility of bitumen with SBS and plastomers. Bitumen samples were suitable for SBS modification and SBS PMBs showed superior elasticity behaviors compared to plastomer blends.     

An evaluation of modified silica nanoparticles’ efficiency in enhancing oil recovery of light and intermediate oil reservoirs

The role of nanoparticles in enhancing oil recovery from oil reservoirs is an increasingly important topic of research. Nanoparticles have the properties that are potentially useful for enhanced oil recovery processes, as they are solid and two orders of magnitude smaller than colloidal particles. This paper presents a comparison between the efficiency of modified silica nanoparticles in enhancing oil recovery from two different Iranian light and intermediate oil reservoirs. The mechanisms used to recover additional oil would be oil–water interfacial tension reduction and wettability alteration. Oil phase contact angles and oil–water interfacial tensions were measured in the absence and the presence of nano fluids’ different concentrations (1–4 g/L). Results showed that the interfacial tension reduces dramatically in the presence of nanoparticles for both light and intermediate oil. In addition oil phase contact angle results showed a transformation of rock wettability from water-wet toward oil-wet condition. However, these nanoparticles are more capable in the reduction of the interfacial tension and the alteration of wettability in the case of light oil reservoir. A comparison between recovery results indicated that these nanoparticles are more efficient in light oil reservoirs and produce more incremental amount of oil after primary and secondary processes.     

Effect of the addition of oligo ester on the rheological properties of bitumen grade 80–100

Many problems have emerged in road construction due to insufficient adhesion and elasticity of asphalt layers as road surface. Adding polymer to bitumen can improve and modify asphalt properties. Oligo ester can be used as an additive to improve bitumen properties. Through reaction of recycled polyethylene terephthalate with dipropyleneglycol, oligo ester was produced during the glycolysis process. In this research, oligo ester was fabricated through glycolysis reaction. Then it was added to the bitumen grade 80–100 in 2 and 5 wt%. The end product was evaluated by standard test methods for ductility, softening point, penetration, and thermal behavior was measured by Thermal Gravimetric, Differential Thermal Gravimetric, and Differential Thermal Analysis. The results revealed that the addition of the above polymers to bitumen reduced penetration property and increased softening point and ductility. Also, thermal behavior of bitumen was modified.     

Stability of vegetable based oils used in the formulation of ecofriendly lubricants – a review

Human need for energy is insatiable. ManBackspace use of conventional and unconventional hydrocarbon sources has served human energy requirements but not without associated challenges of renewability, toxicity, depletion, degradability, and environmental hazards. Since a complete substitute for fossilized-energy sources is yet to be realized, one viable options available to man is alternative, renewable, ecofriendly, and biodegradable energy sources – thus, minimizing complete reliance on mineral based energy sources. Lubricants are finding relevance in product processing, transportation, agriculture, and other key sectors of industrial developments as a result of use of machines to aid human operations. While more than 70% of commercially available lubricants are from crude oil/hydrocarbon, commercial formulation of lubricants using vegetable base oils are gaining global interests. Lubricants obtained from bio-based oils are eco-compatible but are widely reported to be thermally and oxidatively unstable, especially when such biolubricants are produced from crude form of vegetable oils. The aim of this review is to reappraise various scholarly works on thermal-oxidative stability of vegetable oils so as to validate their usefulness as potential alternative and renewable sources of energy used in the production of lubricants as against continuous usage of mineral based energy sources which is ecologically non benign.     

Growth of Listeria monocytogenes in salmon roe – A kinetic analysis

The objective of this study was to investigate the growth kinetics of Listeria monocytogenes in unsalted and salted (3%) salmon roe. Growth curves, developed using inoculated samples incubated at constant temperatures between 5 and 30 °C, were analyzed by curve-fitting to the Huang and Baranyi models using the USDA IPMP 2013. The experimental results showed that L. monocytogenes in salted samples exhibited approximately 40% longer lag times than the cells in unsalted samples under the same temperature condition, while the rates of bacterial growth were not affected by the addition of salt. The Ratkowsky square-root (RSR) model, Huang square-root (HSR) model, and an Arrhenius-type model were all shown suitable for evaluating the effect of temperature on specific growth rates. The estimated nominal minimum growth temperature in the RSR model was −0.5 °C, whereas the minimum growth temperature in HSR model was 2.57 °C. The HSR models may be more suitable for describing the temperature effect in salted salmon roe. The lag times of L. monocytogenes were found to change log-linearly with the specific growth rates. The mean h₀ in the Baranyi model was 0.742 in unsalted samples and 1.193 in salted samples, and did not appear to change with temperature in a systematic manner. In summary, kinetic models were developed for examining the effect of temperature on growth of L. monocytogenes in unsalted and salted salmon roe samples. The results may be used by the food industry and regulatory agencies to estimate the growth of L. monocytogenes in salmon roe, and to conduct risk assessments of this microorganism.