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The boron occupies an important place on contributions and its usage is getting widespread. Although the use of boron-added mineral oils serves to reduce friction, environmental risks can not be totally removed. It is necessary to improve the properties of biological oils used for additives so that they can compete with mineral oils technically. In the study, the use of liquid boron as an additive for engine lubrication oil together with vegetable oil was investigated experimentally in two diesel engines. Experiments were first carried out using mineral lubrication oil in the engine, and then the experiments were repeated using mineral base oil with additives in the second engine with the same technical characteristics as the first engine. Basically, the study was performed in the fields of engine performance (torque, power, consumption per hour, specific fuel consumption) and exhaust emissions (CO, CO2, HC, O2, SO2, NOx). As a result, it was concluded that the engine, in which boron and mineral oil with wild mustard oil were used, provided more significant fuel saving than in the engine with additive-free mineral oil, and no significant change was seen in the engine performance, also they showed similarities in terms of exhaust emissions. [ABSTRACT FROM AUTHOR]

For the development of national industry green environmental protection, the use of zinc dialkyl dithiophosphate (ZDDP) should be reduced in the process of mechanical lubrication, two novel borate esters, SS-(5-disulfanyl-1,3,4-thiadiazol-2-yl) O-(6-stearoyl-1,3,6,2-dioxazaborocan-2-yl) carbono(dithioperoxoate) (BNSD) and 6-stearoyl-1,3,6,2-dioxazaborocan-2-yl stearate (BNCD), were synthesized and characterized by FT-IR and TGA. Tribological performance of ZDDP, BNSD and BNCD as a multifunctional additive in synthetic ester base oil were investigated under different loads using a MR-S10 four-ball and MFT-3000 friction and wear test machine. A scanning electron microscope and laser scanning confocal microscope were used to observe worn scar surface morphology of the balls. The chemical compositions of worn surface were analyzed by X-ray photoelectron spectroscopy and the tribofilm of the worn surface was observed by transmission electron microscope. The TGA curves showed that BNSD and BNCD had a better thermal stability than ZDDP. BNSD exhibits excellent anti-wear and friction-reducing properties, the PB value is increase to 784 N when the optimized concentration is 0.3% the minimum WSD of BNSD-based lubricant is approximately 0.52 mm and decreased by 35% compared with the base oil. A protective tribofilm of the ball steel was analyzed by XPS and TEM, which revealed that B2O3 and Fe2B constitute the triboilm and about 5 nm. Therefore, BNSD could be a candidate as anti-wear and friction-reducing agent in lubricants instead of ZDDP. [ABSTRACT FROM AUTHOR]

The proposed work deals with the investigation of magnetorheological based minimum quantity lubrication of graphene oxide (GO) based jojoba oil as bio-lubricant on machinability and tool wear mechanism of turning Monel K500 alloy. Experiments were carried out for dry, flooded, minimum quantity lubrication (MQL) and magnetorheological (MR–MQL) conditions using medium duty lathe. The process parameters include the cutting speed 95, 110, 125 m/min, feed rate 0.050, 0.075, 0.1 mm/rev and depth of cut 0.25, 0.50, 0.75 mm for the output responses such as surface roughness, cutting temperature and tool flank wear. The results indicated that GO-based bio-lubricant MR–MQL reduced coefficient of friction (COF) of 0.051 and wetting angle of 6°, as well as improved machining performance such as cutting temperature of 145 °C, the surface roughness of 0.614 µm, flank wear of 0.18 mm with enhanced lubrication regime under extreme wear conditions. [ABSTRACT FROM AUTHOR]

Carbon nanospheres, copper nanoparticles and their composite Cu@C having copper nanoparticles embedded in carbonaceous material were synthesized hydrothermally. The analytical techniques; powder X-ray diffraction(XRD), field emission scanning electron microscopy(FE-SEM) with energy-dispersive X-ray spectroscopy(EDX), transmission electron microscopy/high- resolution transmission electron microscopy(TEM/HR-TEM), Raman and X-ray photoelectron spectroscopy (XPS) have been employed for their characterization. Tribological behavior of blends of the synthesized additives with paraffin oil has been investigated on a four-ball lubricant tester using ASTM D4172 and ASTM D5183 at 0.1% w/v concentration. Comparative activity of the base oil and the blends has been adjudicated considering the experimental data for mean wear scar diameter (MWD), coefficient of friction (COF), load-carrying capacity and wear rates collected from the above standard tests. The admixture-containing nanohybrid, Cu@C appears to show the best activity followed by that of copper nanoparticles and then carbon spheres. The relative activity of different admixtures is verified by atomic force microscopy(AFM) and scanning electron microscopy(SEM) with EDX results of the wear pathway. The EDX spectrum of Cu@C shows the existence of copper together with carbon on the wear scar surface confirming their contribution in the formation of in situ tribofilm. Thus, these additives may be approved for enhancing lubrication. [ABSTRACT FROM AUTHOR]

The purpose of this paper is to evaluate carbon spheres as a green lubricant additive in 5W30 engine oil to reduce friction and wear. Carbon spheres with a diameter of ∼400 nm are synthesized from glucose by using a hydrothermal process. Lubrication is studied using a ball-on-disk tribometer by measuring the friction coefficient and wear in the boundary lubrication regimes. The worn surfaces were analyzed by Raman spectroscopy. Carbon spheres are found to be stably dispersed at 0.5 wt% concentration in base oil. The experiments revealed that carbon spheres are effective in reducing both friction and wear when lubricating by using base oil. Raman results show that the enhanced tribological performance is owing to a carbon-rich boundary film, the formation of which is attributed to the deposit of carbon particles during the sliding process. [ABSTRACT FROM AUTHOR]

Thirty-one hydrazides were selected as isosteres and other analogs when five phosphates were used as templates by an isosteric exchange from phosphate group (PO4) to hydrazide group (CONHN). Their tribological properties of the lubricant modified with 1% hydrazide or phosphate additives were tested under 98 N load in three base oils, respectively. About 40% of the isosteres showed an acceptable deviation of ±5% relative to the template. The phosphate template molecules and hydrazide isosteres have better tribological properties in triisodecyl trimellitate than trimethylolpropane trioleate or di(2-ethylhexyl) adipate. Especially, most of the other hydrazide analogs have better antiwear property because of the same CONHN group as the isostere. CoMFA and CoMSIA models were used to discuss the dependency of molecular structure. The models show that the higher the structural similarity between the base oil and the additive, the more synergy the molecular force field in a lubricant, which may ameliorate the antiwear or friction-reduction properties. Surface analysis of the worn disc specimen also shows similarity between a template and an isostere by Scanning Electron Microscopy, EDS, and Raman spectra. [ABSTRACT FROM AUTHOR]

Hydro distilled essential oil of the aerial parts of Caryopteris incana harvested from Zhejiang province, China was analyzed by gas chromatography-mass spectrometry (GC/MS). Thirty-nine components were identified and the principal compounds in the essential oil were 4-terpineol (13.5 %), 1-octen-3-ol (12.3 %), myrtenol (8.8 %), and α-cadinol (8.5 %). Three active compounds (α-cadinol, myrtenol, 4-terpineol) were isolated and identified from the essential oil based on bioactivity-directed fractionation. The essential oil and its isolates, myrtenol and 4-terpineol exhibited fumigant activity against the red flour beetles, Tribolium castaneum with LC50 values of 2.2, 5.6, and 0.5 mg/l, respectively. The essential oil and the three constituents, α-cadinol, myrtenol, and 4-terpineol also displayed contact toxicity against T. castaneum with LC50 values of 30.7, 123.4, 29.7, and 21.3 μg/adult, respectively. The study indicates that the essential oil of C. incana and its isolated constituents have the potential to be developed to natural insecticides for the control of grain storage insects. [ABSTRACT FROM AUTHOR]

Homopolymer of rice bran oil and its copolymer with dodecyl acrylate and styrene were synthesized and characterized by spectral (NMR, IR), thermogravimetric analysis and gel permeation chromatographic methods. Performance of these polymers was evaluated by standard ASTM methods in base oil and showed very effective as pour point depressants and viscosity modifiers. Biodegradability of all these polymers was tested which showed excellent results. A comparison of their performances has also been evaluated and reported. The copolymers showed biodegradability in addition to the multifunctional additive performance (PPD and VM), and so are considered as being more useful in field applications compared to the existing conventional additives. [ABSTRACT FROM AUTHOR]

Carbonium ion can be generated easier when low-carbon alcohols are added to hydrocracking tail oil, which initiate the cracking reaction of macromolecular n-paraffin. So the yield of lube oil base oil increases, while that of paraffin decreases, but the total yield of the two products increases. When the low-carbon alcohol is added to the raw oil for non-hydrodewaxing reaction of hydrocracking tail oil, the pour point of lubricating oil base oil declines, the flash point and the viscosity increases slightly, and the distillation range of paraffin declines slightly, but the properties of products changes little, so they can meet the actual production requirements of the factory. By examining the influence of low-carbon alcohol on the yield and properties of lubricating oil base oil and paraffin, tert-butyl alcohol is an ideal chain initiator, and the most suitable addition is 1.0 w%. [ABSTRACT FROM AUTHOR]

Re-refining of used lubricating oil has appeared as a valuable technique to re-refining of used engine and industrial oils. This paper focused on the vacuum distillation thin wiped film evaporation technique of used lubricating oil recycling. The whole process consists of dehydration, gas oil evaporation, thin wiped film evaporation and clay treatment. The produced base oils are in group I through determination of sulfur contents, percentage of saturate compounds and viscosity indexes. The obtained results are practicable with most of the American Society for Testing and Materials (ASTM) properties and reduced most of worn metals in the refined base oils. [ABSTRACT FROM AUTHOR]

Concern over environment, safety and cost encourages development of separating edible oils by an aqueous process. An advanced pilot method of separating peanut oils based on aqueous extraction was established in this study, which used 1.5:10 liquid-to-peanut seed kernel slurry ratio with addition of 1 g sodium chloride/100 g slurry, agitation at 64℃. It recovered 96.1 ± 0.2% peanut oils with their quality met Chinese national standard for first class refined oil and the dried residue can be directly used in food industry. No waste was produced during aqueous extraction of oil. Conditions affecting the efficiency of aqueous extraction were verified. [ABSTRACT FROM AUTHOR]

This paper first introduces the structure and working principle of a 2D piston pump invented by the research team that the authors are involved with. Afterward, the mechanism of the churning losses caused by the pump's moving parts, which are rotating in oil, is carefully studied by building up mathematical models and using CFD simulations. A test rig is set up to estimate the churning losses of the moving parts by monitoring the torque at different rotational speeds. The analytical results indicated that the torque of the churning losses increased with the increase of the rotational speed. In addition, the experimental data of the churning losses were consistent with the solutions from both the conducted mathematical models and CFD simulations before the rotational speed reached 8000 rpm. However, when the rotational speed exceeded 8000 rpm, the experimental data showed an apparent difference from the calculated ones. Based on the changes in the oil temperature and noise, this difference might be due to cavitation or turbulence. As a result, the churning losses that took place in the 2D high-speed piston pump need to be further studied, especially when the pump is driven by a high-speed motor. [ABSTRACT FROM AUTHOR]

Asphaltene precipitation from crude oil in underground reservoirs and on ground facilities is one of the major problems in a large portion of oil production units around the world. Many scaling equations and intelligent predictive models using the artificial neural network (ANN) are proposed in the literature but none of them can be applied when crude oil is diluted with any types of paraffin. In this study, feed forward artificial neural network is used for prediction of the amount of asphaltene precipitated weight percent of diluted crude oil with paraffin based on titration tests data from published literature. Trial and error method is utilized to optimize the artificial neural network topology in order to enhance its strength of generalization. The results showed that there is good agreement between experimental and predicted values. This predictive model can be applied to estimate the amount of asphaltene precipitated weight percent when the crude oil is diluted with paraffin and to avoid experimental measurement that is time-consuming and requires expensive experimental apparatus as well as complicated interpretation procedure. [ABSTRACT FROM AUTHOR]

Metal oxide nanoparticles of different nature have been used in different fields such as therapeutics, biomarkers, tribology or environmental remediation, among others. Besides, the surface modification of such nanoparticles is of particular interest to bring designed functions. In this paper we describe the synthesis of CuO nanoparticles with two different geometries (spherical and prolate) and decorated with long alkyl chains in order to use as dye removers by adsorption and/or photo-degradation of a persistent model dye (Congo Red) and as lubricant additives to improve the tribological performance of base lubricant oils. Alkyl-functionalized CuO nanoparticles demonstrated a high stability in oily suspensions and an improvement in the friction reducing the CoF ca. 26%; the alkyl-decorated nanoparticles showed also higher adsorption kinetics for Congo Red than the neat ones following a pseudo-second-order trend, although with lower adsorption efficiency. The synthesis, surface modification and physic-chemical characterization of spherical and prolate CuO nanoparticles are described as well as their applications as lubricant additives and Congo Red photocatalytic removal. [ABSTRACT FROM AUTHOR]

One of the severe problems in all the oil production stages from the pore walls of the reservoir rocks to the wellhead, transfer pipelines, and production units of a large portion of the world's hydrocarbon reservoirs, is asphaltene precipitation and deposition from crude oil on solid surfaces. In this article, least squares support vector machine optimized by coupled simulated annealing is employed for estimation of the amount of asphaltene precipitated weight percent of diluted crude oil with paraffin based on titration tests data from a recently published article. The results indicated that there is an excellent correlation between predicted and experimental values with an average absolute relative deviation percent, mean square error, and a determination coefficient of 0.0727%, 0.0242, and 0.9972, respectively. The developed predicting model can be applied to estimate the amount of asphaltene precipitated when the crude oil is diluted with paraffin and to eschew experimental titration test that is tedious and time-consuming. [ABSTRACT FROM AUTHOR]

Polyurethanes (PU) foams with titanium particles (Ti) were prepared with castor oil (CO) and isophorone diisocyanate (IPDI) as polymeric matrix, and 1, 3 and 5 wt.% of Ti. Composites were physicochemically and mechanically characterized and their biocompatibility assessed using human dental pulp stem cells (HDPSC). PU synthesis was confirmed by FTIR, but the presence of Ti was detected by RAMAN, X-ray diffraction (peak at 2θ = 40.2°) and by EDX-mapping. Materials showed three decomposition temperatures between 300 °C and 500 °C and their decomposition were not catalyzed by Ti particles. Compressive modulus (164–846 kPa), compressive strength (12.9–116.7 kPa) and density (128–240 kg/m3) tend to increase with Ti concentration but porosity was reduced (87% to 80%). Composites' foams were fully degraded in acid and oxidative media while remained stable in distilled water. HDPSC viability on all composites was higher than 80% up to 14 days while proliferation dropped up to 60% at 21 days. Overall, these results suggest that these foams can be used as scaffolds for bone tissue regeneration. [ABSTRACT FROM AUTHOR]

This study aimed to evaluate the hydrolysis of rapeseed oil using pyrrolidonium ionic liquids as catalysts under atmospheric pressure. The process parameters were optimized using a sequence of experimental protocols to evaluate the effects of ionic liquid loading, dosage of emulsifier, weight ratios of substrates, temperature and time. The results demonstrated that the ranking of catalytic activity of ionic liquids is N-methyl-2-pyrrolidonium hydrogen sulfate salt ([HNMP]HSO4)>1-(3-sulfonic acid) propyl-2-pyrrolidonium hydrogen sulfate salt ([C3SO3Hnhp]HSO4)>2-pyrrolidonium hydrogen sulfate salt ([Hnhp]HSO4). In a batch reactor, the hydrolysis reaction conditions in the presence of [HNMP]HSO4 were investigated and optimized as follows: catalyst loading of 20% (based on the weight of oil), oil/water weight ratio of 1:2, emulsifier loading dosage of 4 wt % (based on the weight of oil), hydrolysis temperature of 100°C, and hydrolysis time of 30 h. The catalytic performance of this ionic liquid remained excellent even after reuse five times. [ABSTRACT FROM AUTHOR]

Poly(urethane-ether-amide) (PUIEtA) nanocomposite coatings on mild steel were prepared by using corn oil, isosorbide and isophorone diisocynate and fumed silica. The syntheses steps were confirmed by FTIR, 1H NMR and 13C NMR spectroscopy techniques. The morphology of PUIEtA nanocomposite coating was studied by SEM-EDX, that confirmed the presence of nanosilica and thermal behavior was studied by DSC/TGA analysis. The anticorrosion performance of PUIEtA coating systems on mild steel, exposed to 3.5 wt% NaCl solution, was evaluated using electrochemical impedance spectroscopy. Scratch hardness, pencil hardness, adhesion, and bending test were performed in order to investigate the performance of nanocomposite coating on mild steel substrate. It was found that PUIEtA-fumed silica nanocomposite coating could provide much better protection than PUIEtA. PUIEtA-3 nanocomposite coating can be safely used up to 200 °C. [ABSTRACT FROM AUTHOR]

The present study was aimed at preparing and evaluating levocetirizine (LCZD) loaded emulgel containing tamanu oil and sericin for atopic dermatitis (AD) therapy. The emulgel envisaged topical delivery of LCZD utilising natural antioxidants for superior therapeutic outcomes when compared with other conventional therapy. Tamanu oil based microemulsion (ME) was optimised utilising Box-Behnken design (BBD). The OPT-ME displayed globule size 379.5 ± 2.33 nm, polydispersity index 0.284, drug loading 0.41 ± 0.01% w/w, entrapment efficiency 94.34 ± 2.11% w/w and drug release 86.24 ± 4.90% respectively over a period of 24 h. The optimised formulation (OPT-ME) was further incorporated into sericin gel to form emulgel (LSE). In vivo pharmacodynamic studies revealed enhanced therapeutic potential of emulgel in terms of reduced scratching frequency and erythema score when compared with conventional gel. The superior therapeutic potential was further witnessed through histopathological and biochemical studies. The emulgel can be an alternative appropriate dosage form for the treatment of AD. [ABSTRACT FROM AUTHOR]

In a previous study we obtained reference values of solubility parameter of two Brazilian crude oils based on asphaltene flocculation data. In this work, these reference values were compared to those obtained by nine models available in the literature and oil compatibility data were experimentally obtained to enhance the modeling evaluation. These evaluations allowed to select models to predict asphaltene stability and oil compatibility. As a result, only our method along with three other methods can accurately predict the experimental results of the compatibility between oil mixtures, and the conclusion is that usually recommended models are not the best choice. [ABSTRACT FROM AUTHOR]

Foaming tendency of turbine oil is diverse due to the variance in turbine oil components, including the type and content of additives and base oils. A common amine phosphate (AP) was investigated as an anti-wear additive in turbine oil. According to ASTM D892, the AP exhibited severe foam accumulation when blended with five kinds of polyol esters, respectively. There is a positive correlation between foam accumulation volume and elasticity modulus. Moreover, adding 0.02 wt% defoamer (T921) could reduce foam accumulation volume and elasticity modulus effectively. [ABSTRACT FROM AUTHOR]

Through three decades of conflict, food rations delivered through the public distribution system (PDS) have remained the largest safety net among Iraq's population. Reforming the PDS continues to be politically challenging, notwithstanding the system's import dependence, economic distortions, and unsustainable fiscal burden. The oil price decline of mid-2014 and recent efforts to rebuild and recover have put PDS reform back on the agenda. The government needs to find an effective way to deliver broad benefits from a narrow economic base reliant on oil. The study described here adopts a mixed demand approach to analysing household consumption patterns for the purpose of assessing plausible reform scenarios and estimating the direction and scale of the associated welfare costs and transfers. It finds that household consumption of PDS items is relatively inelastic to changes in price, particularly among the poor. The results suggest that any one-shot reform will have sizeable adverse welfare impacts and will need to be preceded by a well-targeted compensation mechanism. To keep welfare constant, subsidy removal in urban areas, for example, would require the poorest and richest households to be compensated for, respectively, 74 per cent and nearly 40 per cent of their PDS expenditures. [ABSTRACT FROM AUTHOR]

Four new azo compounds namely, 2-(sec-butyl)-4-((4-methoxyphenyl)diazenyl) phenyl-4-(hexyloxy)benzoate (I6a), 2-(sec-butyl)-4-(p-tolyldiazenyl)phenyl-4-(hexyloxy) benzoate (I6b), 4-((4-bromophenyl)diazenyl)-2-(sec-butyl)phenyl 4-(hexyloxy)benzoate (I6c) and 2-(sec-butyl)-4-((4-nitrophenyl)diazenyl)phenyl 4-(hexyloxy)benzoate (I6d) were synthesized. Their structure elucidated via Elemental Analysis, FT-IR, 1H-NMR and Mass Spectroscopy. Their mesophase behavior was investigated by Differential Scanning Calorimetry (DSC). They were tested as antioxidants for local base oil. The efficiency of them was investigated via monitoring the oxidation reaction through the change in total acid number (TAN) and viscosity. The obtained results showed that, the efficiency of these compounds was ranked as follows I6d > I6c > I6b > I6a. [ABSTRACT FROM AUTHOR]

Gas-to-liquid (GTL) products are synthetic hydrocarbons produced from natural gas using a catalytic process known as the Fischer-Tropsch process. This process yields a synthetic crude oil that consists of saturated hydrocarbons which can subsequently be refined to a range of products analogous to those obtained from petroleum refining. However, in contrast to their petroleum-derived analogs, GTL products are essentially free of unsaturated or aromatic compounds and do not contain any sulfur-, oxygen-, or nitrogen-containing compounds. Under new chemical substance notification requirements, an extensive testing program covering the entire portfolio of GTL products has been undertaken to assess their hazardous properties to human health and environment. The results of these studies have been summarized in a two-part review. Part 1 provides an overview of the mammalian toxicity hazardous properties of the various GTL products. This second part of the review focuses on the aquatic, sediment, terrestrial, and avian toxicity studies which assess the ecotoxicological hazard profile of the GTL products. Many challenges were encountered during these tests relating to dosing, analysis and interpretation of results. These are discussed with the intent to share experiences to help inform and shape future regulatory mandates for testing of poorly soluble complex substances. As was the case with the mammalian toxicology review, there were a few cases where adverse effects were found, but overall the GTL products were found to exert minimal adverse ecotoxicological effects and these were less severe than effects observed with their conventional, petroleum-derived analogs. [ABSTRACT FROM AUTHOR]

The oxidative stability of three base lubricating oils of different grades light, medium and heavy oils (B1, B2 and B3, respectively) was studied at oxidative times 50, 100 and 150 hours. The quality of base oils under investigation were evaluated on the basis of total acid number, vaporization loss, kinematic viscosity and quantity of sludge formed. Also, the chemical composition of the studied lubricating oils was achieved via capillary gas chromatography. The comparative study of the oxidative performance of the base oils showed that the higher degrees of heavy oil than light one. The increase in the oxidation time led to increases of the evaporation loss and lubricant viscosity. Analysis of a lubricant's oxidation stability therefore contributes to a better understanding of its effectiveness under normal operating conditions and its suitability for formulating automotive lubricants. The aim of this work is the study the Potential life of lubricant oils inside engine motor at different oxidative times in view of their oxidation stability. [ABSTRACT FROM AUTHOR]

In this paper, flocculation and adsorption have been used as an efficient combination for the regeneration of used rolling oil. Polyethyleneimine (PEI) incorporated with polyacrylamide (PAM) as flocculant for treating used rolling oil was examined. The effect of dosages of PEI and PAM was investigated experimentally. The research of a percolation refined adsorption process using different adsorbent materials (silica gel, alumina, and activated carbon) was evaluated. The physical properties and hydrocarbon composition of regenerate oil become similar to the base rolling oil. In addition, the flocculation and adsorption mechanism was also explored. [ABSTRACT FROM AUTHOR]

According to ISO 13357, the filterability of different turbine base oils is measured. It is found that the dry filterability of eight kinds of base oil is better than 100, but there are great differences in the wet filterability, which is significantly lower than respective dry filterability. The relationships between the difference of the filterability and the oil/water interfacial tension are investigated. The results show that the cause of the difference between dry and wet filterability is the hydrogen bonds and the oil/water interfacial tension for the same oil. As for the base oil with ISO viscosity grades (VG) 32, the wet filterability increases with the increase of the oil/water interface tension. On the other hand, the base oil with ISO VG 68, there is no significant correlation between oil/water interface tension and wet filterability. [ABSTRACT FROM PUBLISHER]

Gas-to-liquid (GTL) products are synthetic hydrocarbons produced from natural gas using a Fischer–Tropsch process. This process yields a synthetic crude oil that consists of saturated hydrocarbons, primarily linear alkanes, with increasing amounts of branched (methyl-groups) alkanes as the chains get longer. In addition, small amounts of cycloalkanes (branched cyclopentanes and cyclohexanes) may be formed as the polymerization reaction prolongs. This synthetic crude can subsequently be refined to a range of products very similar to petroleum refining. However, in contrast to their petroleum-derived analogs, GTL products are essentially free of unsaturated or aromatic constituents and also no sulfur-, oxygen-, or nitrogen-containing constituents are present. From a regulatory perspective, GTL products are new substances which require extensive testing to assess their hazardous properties. As a consequence, a wide range of GTL products, covering the entire portfolio of GTL products, have been tested over the past few years in a wide variety of toxicological studies, including reproductive and prenatal development toxicity studies. This review provides an overview of the hazardous properties of the various GTL products. In general, the data collected on GTL products provide strong proof that they exert minimal health effects. In addition, these data provide supporting evidence for what is known on the mechanisms of mammalian toxicology of their petroleum-derived analogs. In the few cases where adverse effects were found for the GTL substances, these were usually less severe than the adverse effects observed with their petroleum-derived analogs. [ABSTRACT FROM PUBLISHER]

Copolymers of different concentration of decyl acrylate and 1-decene with rice bran oil were prepared and their characterization was carried out by spectral (NMR, IR), thermogravimetric, and gel permeation chromatography analysis. Performance evaluation of them in lube oil indicates that the polymers effectively act as pour point depressant and viscosity modifier. The viscosity index and pour point values depend on the nature of mineral base oils, polymer type, and also on the concentration of the additives in solution. Biodegradability test was also carried out and as anticipated, the rice bran oil–copolymers showed excellent biodegradable nature among the additives. [ABSTRACT FROM AUTHOR]

A new type of hyper-dispersant was designed and successfully synthesized by free radical solution polymerization method to improve the dispersing performance of nano-copper in base oil. The microstructures of the product were characterized by means of x-ray diffraction (XRD), Fourier transformation infrared spectrometry (FTIR), and transmission electron microscopy (TEM). The hyper-dispersant as modifier was chemically bonded to nano-copper via strong chemical interaction. The influences of nano-copper modified by hyper-dispersant on the lipophilic degree and wettability were investigated. It was found that the modified nano-copper had the best dispersion performance in base oil, and the optimum amount of hyper-dispersant was 8 wt%. The tribological behavior showed that modified copper nanoparticles possessed excellent friction-reduction and antiwear properties. Meanwhile, the extreme pressure property of the base oil was also improved strikingly. And the maximum non-seizure load (PB) of base oil was improved by 27% at the point of 0.1 wt%. [ABSTRACT FROM PUBLISHER]

A stable ester was synthesized to overcome the ester hydrolysis problem during the drilling of oil or gas wells using a conventional ester-based drilling fluid. The thermal and hydrolytic stability of the produced ester was high owing to the transesterification method employed in this study. The reaction was performed using 2-ethylhexanol and methyl laureate esters in the presence of sodium methoxide as a catalyst. In order to obtain the optimum synthesis conditions, a response surface methodology (RSM) was appraised based on the central composite design (CCD). The optimum conditions were determined as follows: 0.6 wt.% catalyst, 70°C reaction temperature, 1:1.5 molar ratio, and 11.5 min of reaction time. The results of 77 wt.% 2-ethylhexyl ester (2-EH) illustrated a high agreement between the experimental and RSM models. The reaction product contained 77 wt.% 2-EH and 23% 2-ethylhexanol. The kinematic viscosity was 5 mm2/s at 40°C and 1.5 mm2/sec at 100°C; the specific gravity was 0.854, flash point was 170°C, and pour point was −7°C. The produced product showed similar properties to the available commercial product. However, it was observed that the mud formulation using the synthesized base oil had superior rheological properties at 121°C. [ABSTRACT FROM AUTHOR]

Solvent neutral 100 (SN-100), SN-150, SN-500, and SN-650 base oils have been investigated by electrochemical impedance spectroscopy (EIS). The investigation has been followed in the frequency range of 100 kHz to 1 mHz. The results indicate that in all cases upon decrease of frequency, the impedance (Z) will be raised up. Also obtained data designates that at each applied frequency, Z values vary in the order: SN-100 < SN-150 < SN-500 < SN-650. In all cases, plots of phase angle versus log of frequency are nearly peak shaped. Based on the composition of base oils, the possible reasons for the different observations has been discussed. The equivalent circuit consists of a parallel constant phase element and polarized resistance (Rct), in series with solution resistance (Rs). Linear correlation has been observed between Rctand viscosity at 40 or 100°C, as well as log Rctand viscosity index or specific gravity. [ABSTRACT FROM AUTHOR]

Homopolymer of myristyl acrylate was prepared by microwave assisted free radical polymerization method using BZP as initiator with variation of time at a fixed power without any solvent. Characterization of the polymers was done by IR, NMR, and viscometric analysis. Additive performances of each of them (pour point depressant [PPD] and viscosity modifier [VM]) for lubricating oil (lube oil) were also evaluated by standard ASTM methods. A comparison of their performances has also been reported. The molecular weights of the polymers were determined from viscosity measurements in toluene at 313 K and thermal stability was measured by thermogravimetric analysis. [ABSTRACT FROM AUTHOR]

Homopolymer of acrylate of a mixture of myristyl (C14), dodecyl (C12), and decyl (C10) alcohols in 2:1:1 molar ratio was synthesized by two different ways, microwave-assisted method and thermal method using benzoyl peroxide as initiator. The polymers were characterized by spectroscopic (NMR, IR) and viscometric analysis. Performances of each of them as a pour point depressant and viscosity modifier for lubricating oil (lube oil) were also evaluated by standard ASTM methods. Oil thickening property of the polymers has also been investigated and reported here. Thermal stability of the polymers was determined by thermogravimetric analysis. [ABSTRACT FROM AUTHOR]

Poly (L-lactic acid) (PLLA) microspheres were prepared by a solvent evaporation method based on an oil/water emulsion. The effect of the mass ratio of PLLA and poly(vinyl alcohol) (PVA) on the formation of the microspheres was discussed, and the influence of extraction speed of dichloromethane on the microsphere morphology was also studied. Moreover, the influences of the PLLA concentration and the volume ratio of water phase to dichloromethane phase were investigated. The results showed that stable microspheres can be obtained under the conditions that the mass ratio of PLLA to PVA is 20:1. Porous microspheres were obtained under faster evaporating speed of dichloromethane. The microsphere size increased with increasing PLLA concentration. The microsphere size also increased with the increase of the volume ratio of water phase to dichloromethane phase. [ABSTRACT FROM AUTHOR]

Silica nanoparticles (SiO2 NPs) synthesized by the sol–gel approach were engineered for size and surface properties by grafting hydrophobic chains to prevent their aggregation and facilitate their contact with the phase boundary, thus improving their dispersibility in lubricant base oils. The surface modification was performed by covalent binding of long chain alkyl functionalities using lauric acid and decanoyl chloride to the SiO2 NP surface. The hybrid SiO2 NPs were characterized by scanning electron microscopy, transmission electron microscopy, Fourier transform infrared spectroscopy, simultaneous differential thermal analysis, nuclear magnetic resonance and dynamic light scattering, while their dispersion in two base oils was studied by static multiple light scattering at low (0.01% w/v) and high (0.50%w/v) concentrations. The nature of the functional layer and the functionalization degree seemed to be directly involved in the stability of the suspensions. The potential use of the functional SiO2 NPs as lubricant additives in base oils, specially designed for being used in hydraulic circuits, has been outlined by analyzing the tribological properties of the dispersions. The dendritic structure of the external layer played a key role in the tribological characteristics of the material by reducing the friction coefficient and wear. These nanoparticles reduce drastically the waste of energy in friction processes and are more environmentally friendly than other additives. [ABSTRACT FROM AUTHOR]