Mineral Oil Solution Research Articles

In Vitro Reconstitution of the Actin Cytoskeleton Inside Giant Unilamellar Vesicles.

The actin cytoskeleton, the principal mechanical machinery in the cell, mediates numerous essential physical cellular activities, including cell deformation, division, migration, and adhesion. However, studying the dynamics and structure of the actin network in vivo is complicated by the biochemical and genetic regulation within live cells. To build a minimal model devoid of intracellular biochemical regulation, actin is encapsulated inside giant unilamellar vesicles (GUVs, also called liposomes). The biomimetic liposomes are cell-sized and facilitate a quantitative insight into the mechanical and dynamical properties of the cytoskeleton network, opening a viable route for bottom-up synthetic biology. To generate liposomes for encapsulation, the inverted emulsion method (also referred to as the emulsion transfer method) is utilized, which is one of the most successful techniques for encapsulating complex solutions into liposomes to prepare various cell-mimicking systems. With this method, a mixture of proteins of interest is added to the inner buffer, which is later emulsified in a phospholipid-containing mineral oil solution to form monolayer lipid droplets. The desired liposomes are generated from monolayer lipid droplets crossing a lipid/oil-water interface. This method enables the encapsulation of concentrated actin polymers into the liposomes with desired lipid components, paving the way for in vitro reconstitution of a biomimicking cytoskeleton network.

Peripheral vestibular disease caused by Raillietia auris in a Barzona bull in the USA

AbstractA 2.5‐year‐old Barzona bull presented for right‐sided head tilt and decreased libido of three‐week duration. Video otoscopy of the external ear canal revealed severe erythema, stenosis, purulent debris, necrosis and numerous live Raillietia auris mites. Decontamination via saline lavages, injectable ceftiofur and dexamethasone treatments failed. Topical 10% permethrin solution in mineral oil proved efficacious at killing R. auris mites, and injectable tulathromycin and dexamethasone were administered until resolution of the bacterial otitis; however, the head tilt persisted, and the bull was slaughtered. Systemic administration of ceftiofur was not effective as a sole treatment, and topical antimicrobial treatments were significantly limited per Food Animal Residue Avoidance Databank regulations. Video otoscopy was a useful tool in the rapid diagnosis and management of the otitis. This case highlights the long‐lasting impact of otitis secondary to R. auris mite infestation and the importance of ectoparasite control and rapid treatment of otitis in bovids.

Direct high sensitive determination of elements in gasoline, kerosene, and mineral oil solutions by inductively coupled plasma atomic emission spectrometry (ICP-AES)

Direct ICP-AES analysis of petroleum products, organic solvents and fuels is oftentimes possible only in the mode of radial plasma viewing and requires the use of special sample injection systems, the design of which depends significantly on the physical properties of the sample, in particular, on its volatility and viscosity. Volatile oil fractions and products (naphtha, gasoline), as well as and heavy and viscous oil fractions of and petroleum products (vacuum gas oil, fuel oil, thick lubricating oils) are the most problematic objects of analysis. We consider the possibility of direct analysis of the samples based on gasoline, kerosene and lubricating oils dissolved in kerosene using inductively coupled plasma atomic emission spectrometry (ICP-AES). The possibility of using various configurations of sample injection systems and modes of plasma viewing of vertically located torch for direct analysis of the samples based on kerosene and gasoline is considered. A significant improvement in the sensitivity of determination of the elements in gasoline and kerosene using an axial plasma viewing combined with optimal configurations of sample introduction systems and plasma burning modes is demonstrated.

Facile fabrication of omniphobic PVDF composite membrane via a waterborne coating for anti-wetting and anti-fouling membrane distillation

Omniphobic membranes have been brought to great attention recently regarding the ability to resist both water and low surface tension liquids, thus can be utilized for desalination of saline wastewater containing low surface tension contaminants in membrane distillation (MD). In this study, a facile, environment-friendly, and one-step strategy is developed for fabricating an omniphobic membrane with re-entrant structure and low surface energy by spraying a waterborne coating solution comprising of fluorocarbon surfactant (FS, Zonyl@8867L), fluorinated alkyl silane (FAS), and silicon dioxide nano-particles (SiO2 NPs) onto amino functionalized polyvinylidene difluoride (PVDF) membrane via electrostatic adsorption. As a result, the prepared omniphobic FS/FAS/Si membrane possesses high liquid repellency to water, diiodomethane, mineral oil-in-water emulsion (0.10 % v/v), mineral oil, and SDS solution (0.40 mM) with the contact angle of 164.40 ± 0.95°, 159.12 ± 3.12°, 154.31 ± 3.71°, 153.31 ± 2.09°, and 157.14 ± 3.29°, respectively. Compared to the original PVDF membrane, the omniphobic FS/FAS/Si membrane displays higher rejection (about 99.99%) and superior anti-wetting and anti-fouling characteristics even to the saline feed solution with surfactants, oil pollutants, or hydrophilic organic pollutants in MD process. The results mentioned above verify that the obtained omniphobic FS/FAS/Si membrane has potential application for the desalination of the high saline wastewater containing low surface tension contaminants.

The rheological response of carbonyl iron particles suspended in mineral oil solution of 12-hydroxy stearic acid

In this study, carbonyl iron based magnetorheological fluids (MRFs) with 12-hydroxy stearic acid (12-HSA) oil solutions as carrier were fabricated. Rheological performance of the magnetorheological fluid, including viscosity, yielding, magnetic hysteresis, dynamic modulus as well as thixotropic behavior, was investigated by using a rotational rheometer equipped with a magnetic device. It is found that the 12-HSA gave rise to an increase in the off-state viscosity and shear stress in the absence of magnetic field, indicating gel structure developed in the suspensions. This gel network associating with field-induced particle structure lead a substantial yield stress and dynamic modulus. The hysteresis test validated that the gel like network had a certain effect on maintaining the aggregation structure after removing the magnetic field. Dynamic oscillatory tests showed that 12-HSA solution based MRF exhibits solidlike property in the absence of magnetic field. The dependence of plateau value G′ on magnetic field showed relationship of natural logarithm. Regarding to the thixotropy, a longer recovery progress was observed in 12-HSA solution based MRF due to the restriction of gel network. The sedimentation measurements revealed that the strong flocculation could be formed by 12-HSA and enhances the stability of suspensions.

Sustained Dye Release Using Poly(urea-urethane)/Cellulose Nanocrystal Composite Microcapsules.

The aim of this study is to develop methods to reinforce polymeric microspheres with cellulose nanocrystals (CNCs) to make eco-friendly microcapsules for a variety of applications such as medicines, perfumes, nutrients, pesticides, and phase change materials. Surface hydrophobization treatments for CNCs were performed by grafting poly(lactic acid) oligomers and fatty acids (FAs) to enhance the dispersion of nanoparticles in the polymeric shell. Then, a straightforward process is demonstrated to design sustained release microcapsules by the incorporation of the modified CNCs (mCNCs) in the shell structure. The combination of the mCNC dispersion with subsequent interfacial polyurea (PU) to form composite capsules as well as their morphology, composition, mechanical properties, and release rates were examined in this study. The PU microcapsules embedded with the mCNC were characterized by Fourier transform infrared spectroscopy (FT-IR) and thermogravimetric analysis (TGA). The morphologies of the microcapsules were characterized by optical microscopy (OM) and scanning electron microscope (SEM). The rupture stress and failure behavior of the microcapsules were determined through single-capsule compression tests. Oil-soluble Sudan II dye solution in mineral oil was utilized as a model hydrophobic fill, representing other latent fills with low partition coefficients, and their encapsulation efficiency was measured spectroscopically. The release rates of the encapsulated dye from the microcapsules were examined spectroscopically by both ethanol and 2-ethyl-1-hexanol medium at room temperature. The concentration of released dye was determined by using UV-vis absorption spectrometry (UV-vis). The mCNC embedded poly(urea-urethane) capsules have strong and dense walls, which function as excellent barriers against leakage due to their extended diffusion path length and ensure enough mechanical strength from rupture for handling or postprocessing.

Omniphobic Polyvinylidene Fluoride (PVDF) Membrane for Desalination of Shale Gas Produced Water by Membrane Distillation.

Microporous membranes fabricated from hydrophobic polymers such as polyvinylidene fluoride (PVDF) have been widely used for membrane distillation (MD). However, hydrophobic MD membranes are prone to wetting by low surface tension substances, thereby limiting their use in treating challenging industrial wastewaters, such as shale gas produced water. In this study, we present a facile and scalable approach for the fabrication of omniphobic polyvinylidene fluoride (PVDF) membranes that repel both water and oil. Positive surface charge was imparted to an alkaline-treated PVDF membrane by aminosilane functionalization, which enabled irreversible binding of negatively charged silica nanoparticles (SiNPs) to the membrane through electrostatic attraction. The membrane with grafted SiNPs was then coated with fluoroalkylsilane (perfluorodecyltrichlorosilane) to lower the membrane surface energy. Results from contact angle measurements with mineral oil and surfactant solution demonstrated that overlaying SiNPs with ultralow surface energy significantly enhanced the wetting resistance of the membrane against low surface tension liquids. We also evaluated desalination performance of the modified membrane in direct contact membrane distillation with a synthetic wastewater containing surfactant (sodium dodecyl sulfate) and mineral oil, as well as with shale gas produced water. The omniphobic membrane exhibited a stable MD performance, demonstrating its potential application for desalination of challenging industrial wastewaters containing diverse low surface tension contaminants.

The Study of Chromatography Used In Separation Science

A procedure to determine effective diffusion coefficients of proteins in chromatographic gels, required as model input parameters, is presented. An experimental methodology based on frontal liquid chromatography was combined with a numerical methodology based on a detailed mathematical model describing the chromatographic process including the extra-column dispersion, the dispersion due to the packed bed, the external mass transfer from the bulk phase to the stationary phase, and the diffusive transport within the stationary phase. The procedure has several advantages compared to previously reported methods to determine diffusion coefficients in that no other equipment than an HPLC is required, any class of stationary phases can be investigated as long as the experiments are performed under non-binding conditions, and no modification, e.g., molding of slabs or membranes, to the stationary phase is required. To show the applicability of the procedure, the effective diffusion coefficients of lysozyme, bovine serum albumin, and immunoglobulin γ in Sepharose™ CL-4B were determined and shown to be comparable to those determined by other methods. Molecularly imprinted polymers (MIPs) are man-made polymeric materials with molecular recognition abilities. They mimic the molecular recognition of naturally occurring molecular recognition elements such as receptors and antibodies by binding target molecules by either non-covalent, covalent, or metal-coordinating interactions. Traditionally, MIPs are synthesized in the form of monolithic polymers which are subsequently crushed, ground, and sieved to an appropriate size range. In this thesis, a suspension polymerization method to prepare MIPs in the shape of spherical beads is presented. The method involves suspending a prepolymerization solution in mineral oil, used as the continuous phase. The droplets are transformed into solid spherical beads by free-radical polymerization. The beads have been shown to compare well to the traditional irregularly shaped particles prepared from monoliths. The advantages of the method compared to previously reported methods are the low cost and commercial availability of the continuous phase and the absence of the need for stabilizers for the formation of droplets of pre-polymerization solution in the mineral oil. When compared to the method to prepare particles from monolithic polymers, this method is advantageous due to the spherical shape of the resulting beads and the reduction in time needed to prepare a MIP. When a new MIP is designed, the traditional approach is to use eithera previously reported protocol or rules of thumb based on previous knowledge. This results in non optimized MIPs. The number of possible combinations of monomers, cross-linkers, solvents, and initiators are huge. A full optimization of a MIP formulation therefore requires a large number of experiments. To facilitate the efforts, chemometrics was applied to the work described in this thesis. Three factors (i.e., the amount of monomer, the amount of crosslinker, and the amount of porogen) were chosen as the factors in the model. Multivariate data analysis of the binding to the MIPs indicated how the factors influenced the binding and an optimized MIP composition was identified. The combined use of the suspension polymerization method to produce spherical beads with the application of chemometrics was shown in this thesis to drastically reduce the number of experiments and the time needed to design and optimize a new MIP.

Some Cavitation Properties of Liquids

Cavitation properties of liquid must be taken into consideration in the engineering design of hydraulic machines and hydro devices when there is a possibility that in their operation an absolute pressure in the liquid drops below atmospheric one, and for a certain time the liquid is in depression state. Cold boiling, which occurs at a comparatively low temperature under a reduced absolute pressure within or on the surface of the liquid is regarded as hydrostatic cavitation if the liquid is stationary or as hydrodynamic cavitation, if the liquid falls into conditions when in the flow cross-section there is a sharply increasing dynamic pressure and a dropping absolute pressure. In accordance with the theory of cavitation, the first phase of cavitation occurs when the absolute pressure of the degassed liquid drops to the saturated vapour pressure, and the air dissolved in the liquid, leaving the intermolecular space, is converted into micro-bubbles of combined air and becomes a generator of cavitation “nuclei”. A quantitative estimate of the minimum allowable absolute pressure in a real, fully or partially degassed liquid at which a hydrostatic cavitation occurs is of practical interest. Since the pressure of saturated vapour of a liquid is, to a certain extent, related to the forces of intermolecular interaction, it is necessary to have information on the cavitation properties of technical solutions, including air solution in a liquid, as a solute may weaken intermolecular bonds and affect the pressure value of the saturated solvent vapour. In the experiment to carry out vacuum degassing of liquids was used a hydraulic air driven vacuum pump. The paper presents hydrostatic and hydrodynamic degassing liquid processes used in the experiment. The experimental studies of the cavitation properties of technical liquids (sea and distilled water, saturated NaCl solution, and pure glycerol and as a 49/51% solution in water, mineral oil and jet fuel) enabled us to have an quantitative estimate of the absolute pressure in the allowable technical liquids and solutions, its dependence on the saturated vapour pressure, as well as to define the influence of a degree of the hydrodynamic degassing of liquid and the amount of its solute on the liquid tensile strength. The paper gives a comparative assessment of cavitation properties of liquids. When studying the cavitation properties of solutions it has been found that a level of the allowable absolute pressure in a solution exceeds that of in the solvent. It is suggested that the dissolved solid, liquid or gaseous substances weaken the intermolecular bonds of the solvent and increase the pressure of its saturated vapour.

Methodology for Optical Imaging of NAPL 3D Distribution in Transparent Porous Media

Three-dimensional mapping of non-aqueous phase liquid (NAPL) distribution within saturated porous media is an important issue in bench-scale geo-environmental studies. In this paper, a methodology for optical imaging of 3D multiphase liquid distribution is presented. The natural aquifer is simulated using a transparent soil surrogate that represents the macroscopic behavior of natural sand. To achieve transparency transparent fused quartz grains were saturated with a matched refractive index mineral oil solution that represents the natural aquifer and injected with a green-dyed sucrose solution to simulate dense NAPL contamination. The spatial volume was first estimated and then reconstructed using orthogonal images acquired at the model boundaries at various stages of contamination and remediation. Color space analysis was employed to segment the NAPL zone and transform pixel information into integrated concentration values using a previously published calibration model. The chromatic components CR and a of YCBCR and Lab, respectively, were combined to render the spatial concentration profile. A novel iterative reconstruction algorithm named 3D carving was used to resolve three 2D projections into a 3D model. The results show that the proposed methodology provides better efficacy for NAPL zone reconstruction in comparison with conventional image analysis routines. The technology presented in this paper is a sustainable, fast, accurate, non-intrusive, and inexpensive method for spatial mapping of contamination zones using bench-scale transparent soil models.

Mathematical Modeling of a Dip-Coating Process Using a Generalized Newtonian Fluid. 2. Model Validation and Sensitivity Analysis

Dip coating is a simple, straightforward, and economical technique used in many food industrial applications. The objective of this work was to validate a mathematical model (presented by the authors in a companion paper as Part 1) of the fluid-dynamic variables in a dip-coating process considering that the film-forming fluid behaves as a generalized Newtonian fluid, with data obtained from literature, and to perform a sensitivity analysis. A validation process was carried out using experimental data of average film thickness of different film-forming fluids (commercial milk chocolate, commercial deep-fat frying batters, glycerol/water solutions, sugar/syrup solutions, glycerine/water solutions, mineral oil, and Carbopol solutions). On the basis of the low errors obtained, predictions were considered satisfactory. An extensive examination of the effect of the main process variables, such as τ0, K, n, m, Up, ρ, θ and h, on the velocity profile and the characteristics of the local and average film thickness was established.

Oscillations in light-triggered logic microfluidic circuit

Control of droplets in microfluidic environments has numerous applications ranging from analysis and sample preparation for biomaterials synthesis (Mann and Ozin Nature 382:313–318, 1996) and medical diagnostics (Pipper et al. Nat Med 13:1259–1263, 2007) to photonics (Schmidt and Hawkins Nat Photonics 5:598–604, 2011). Here we study the oscillations present in a microfluidic circuit capable of sorting curable droplets on demand by triggering the circuit with UV-light. Prior to this paper we showed that a simple circuit can self-sort particles and produce a binary output, sorted or rejected stream of particles, based on the hydrodynamic resistance induced by the particles as they flow through the microfluidic channels. We showed that the cross-linking of droplets can modulate the resistance, and demonstrated particle switching by sorting of otherwise identical droplets of uncured and cured photocurable solution immersed in mineral oil solution. Before arriving at the sorting circuit, droplets made of a photocurable solution were illuminated by a UV-light from a mercury lamp, curing them. By tuning the outlet pressures, the switching threshold could be tuned so that uncured droplets were rejected while cured droplets were switched (Raafat et al. μTAS Proc 1826–1828, 2010; Cartas-Ayala et al. Small 9:375–381, 2013). Here we use this system to study the oscillations in this circuit due to particle–particle interactions in the circuit. The circuit oscillation can be used as a counter with a light ON/OFF switch. The circuit behavior agrees well with theoretical predictions of droplet oscillations. Furthermore, the circuit oscillations can be switched on or off by UV-light illumination. This experiment demonstrates switching of particles based on deformability, illustrates the switching of particles by using light, and the possibility of creating new managing schemes for droplets by combining light control with droplet generation-rate control.

Qualidade de ovos de codorna submetidos ou não a tratamento superficial da casca armazenados em diferentes ambientes

Com o objetivo de avaliar a qualidade de ovos de codornas japonesas tratados superficialmente, através de imersão em óleo mineral ou solução de própolis, foram conduzidos experimentos simultâneos em dois ambientes, sem refrigeração (Experimento 1) e com refrigeração (Experimento 2). Para cada experimento, foram selecionados 360 ovos íntegros distribuídos em delineamento inteiramente casualizado em esquema fatorial 3 x 5 (ovos não tratados; ovos imersos em solução de própolis e ovos imersos em óleo mineral, avaliados durante cinco tempos de armazenamento: 7; 14; 21; 28 e 35 dias), cada tratamento foi composto por seis repetições de quatro ovos cada. Os ovos apresentaram aumento da perda de peso, diminuição do peso específico e aumento do peso e do pH da gema, além de redução do pH do albúmen e de seu respectivo peso com o avançar do tempo de estocagem na ausência de refrigeração (Experimento 1), independente se receberam ou não tratamento na casca. Entretanto, o tratamento superficial com óleo mineral promoveu proteção contra essa perda progressiva de peso e diminuição do peso específico, tornando-as menos intensas com o avançar do período de estocagem sem refrigeração. No Experimento 2, a imersão dos ovos em óleo mineral conferiu menor perda de peso, maior peso específico, maior peso de gema e de albúmen durante o armazenamento sob refrigeração. A qualidade de ovos de codornas submetidos a tratamento superficial da casca por imersão em óleo mineral é preservada por até cinco semanas em diferentes ambientes, sem e com refrigeração.

Determination of Na, K, Mg and Ca in biodiesel by LS F AAS and HR-CS F AAS: studies that supported the proposal of the ABNT NBR 15556 norm

Recently, ABNT (Brazilian Association of Technical Standards) has presented a set of norms related to the determination of Na, K, Mg and Ca in biodiesel, recommending procedures similar to those of the European and American norms. However, it has also introduced an alternative norm (ABNT NBR 15556) wherein these 4 elements can be determined by flame atomic absorption spectrometry (F AAS). This work presents the studies that have supported this proposal and compares the performance of linear source equipment with a continuous source one in the application of the norm. Among the optimized factors, the low aspiration rate and the use of mineral oil solution in xylene to adjust the viscosity between samples and calibration solutions are highlighted. Precision tests (repeatability and intermediary precision) have shown adequate values, confirming the robustness of the method. Limits of detection were suitably below the legislation limits. The accuracy was confirmed by recovery tests as well as by the participation in interlaboratory proficiency tests promoted by the National Agency on Oil, Natural Gas and Biofuels (ANP, Brazil). The determination of these 4 elements by F AAS brings evident economic advantages to the producer, once F AAS is less expensive to purchase and maintenance.

Submicron bioactive glass tubes for bone tissue engineering

Herein we describe a method to fabricate submicron bioactive glass tubes using sol–gel and coaxial electrospinning techniques for applications in bone tissue engineering. Heavy mineral oil and gel solution were delivered by two independent syringe pumps during the coaxial electrospinning process. Subsequently, submicron bioactive glass tubes were obtained by removal of poly(vinyl pyrrolidone) and heavy mineral oil via calcination at 600 °C for 5 h. Tubular structure was confirmed by scanning electron microscopy and transmission electron microscopy imaging. We examined the bioactivity of submicron bioactive glass tubes and fibers and evaluated their biocompatibility, using electrospun poly(ε-caprolactone) fibers – a bioinactive material – for comparison. The bioactivity of the glass tubes was examined in a simulated body fluid and they demonstrated the formation of hydroxyapatite-like minerals on both the outer and inner surfaces. In contrast, mineralization only occurred on their surface for bioactive glass solid fibers. Energy-dispersive X-ray data suggested that the bioactive glass tubes had a faster induction of mineral formation than the solid fibers. We demonstrate that the proliferation rate of mouse preosteoblastic MC3T3-E1 cells on bioactive glass tubes was comparable to that on solid fibers. We also show that bioactive glass tubes can be loaded with a model protein drug, bovine serum albumin, and that these structures exhibit delayed release properties. The bioactivity of released lysozyme can be as high as 90.9%. Taken together, these data suggest that submicron bioactive glass tubes could hold great potential for use in bone tissue engineering as well as topical drug or gene delivery.

Development and optimization of a dual-photoinitiator, emulsion-based technique for rapid generation of cell-laden hydrogel microspheres

A growing number of clinical trials explore the use of cell-based therapies for the treatment of disease and restoration of damaged tissue; however, limited cell survival and engraftment remains a significant challenge. As the field continues to progress, microencapsulation strategies are proving to be a valuable tool for protecting and supporting these cell therapies while preserving minimally invasive delivery. This work presents a novel, dual-photoinitiator technique for encapsulation of cells within hydrogel microspheres. A desktop vortexer was used to generate an emulsion of poly(ethylene glycol) diacrylate (PEGDA) or PEGDA-based precursor solution in mineral oil. Through an optimized combination of photoinitiators added to both the aqueous and the oil phase, rapid gelation of the suspended polymer droplets was achieved. The photoinitiator combination provided superior cross-linking consistency and greater particle yield, and required lower overall initiator concentrations compared with a single initiator system. When cells were combined with the precursor solution, these benefits translated to excellent microencapsulation yield with 60–80% viability for the tested cell types. It was further shown that the scaffold material could be modified with cell-adhesive peptides to be used as surface-seeded microcarriers, or additionally with enzymatically degradable sequences to support three-dimensional spreading, migration and long-term culture of encapsulated cells. Three cell lines relevant to neural stem cell therapies are demonstrated here, but this technology is adaptable, scalable and easy to implement with standard laboratory equipment, making it a useful tool for advancing the next generation of cell-based therapeutics.

Mineral Oil–Chitosan Emulsion Coatings Affect Quality and Shelf‐Life of Coated Eggs during Refrigerated and Room Temperature Storage

Effects of mineral oil (MO) and 4 emulsions (prepared with different emulsifier types) of MO and chitosan solution (CH) at a fixed ratio of MO:CH = 25:75 as coating materials in preserving the internal quality of eggs were evaluated during 5 wk at 25 °C and 20 wk at 4 °C. Generally, as storage time increased, Haugh unit and yolk index values decreased whereas weight loss increased. However, MO and/or 4 emulsion coatings minimized the weight loss (<1.5%) and preserved the albumen and yolk quality of eggs (with the final B grade) for at least 3 wk longer than those observed for noncoated eggs at 25 °C. At 4 °C, all coated eggs changed from AA to A grade after 5 wk and they maintained this grade for 10 wk (5 wk longer than that of noncoated eggs). Although refrigeration (4 °C) alone could maintain the B grade of noncoated eggs for up to 20 wk, coating treatments were necessary to keep the weight loss below 2%. Compared with 4 °C, the increasing weight loss showed stronger negative correlation (P < 0.01) with the decreasing Haugh unit (-0.46 to -0.89) and yolk index (-0.36 to -0.89) at 25 °C. The emulsifier type used in this study generally did not affect the internal quality of eggs. Salmonella spp. detection was negative for all coated and noncoated eggs. This study demonstrated that MO and MO:CH emulsion coatings preserved the internal quality, prolonged the shelf-life, and minimized weight loss (<2%) of eggs.

Surfactant dithiophosphates lubricating oil additives

This paper presents a research on the tribological properties and the action mechanisms of surfactant lubricating oil additives, polyalkoxy glycol ammonium salts and O,O,S-triesters of polyalkoxy glycol dithiophosphoric acid. To understand the physicochemical properties of surfactants, polyalkoxy glycol dithiophosphoric acid behaviour both in solution and at metal surfaces are identified and discussed. The STM adsorption on steel surface, four-ball and ball disc tests of friction of water, synthetic and mineral oil solutions studies of these additives are presented. Friction and wear properties are dependent on tribological parameters, chemical structure of the additives and their surface active behaviour in tribological systems. The relationships are presented on the example of additives with different molecular structures and masses.

Proficiency test on the determination of mineral oil in sunflower oil

AbstractFollowing the discovery of mineral oil contamination of Ukrainian sunflower oil in April 2008, the Institute for Reference Materials and Measurements (IRMM) of the European Commission's Joint Research Centre (JRC) was requested by the Directorate General Health and Consumers (DG SANCO) to organise a proficiency test on the determination of mineral oil in sunflower oil. The aim of this test was to evaluate the comparability of analysis results gained by laboratories in the EU and the Ukraine. The organisation of the study and the evaluation of the results were done in accordance with “The International Harmonised Protocol for the Proficiency Testing of Analytical Chemistry Laboratories” and ISO Guide 43. Altogether 62 laboratories from 19 EU member states, Switzerland and the Ukraine subscribed for participation in the study. Four test samples at concentration levels between about 100 and 350 mg/kg, comprising contaminated crude sunflower oil, contaminated refined sunflower oil, and spiked sunflower oil, and a solution of mineral oil in n‐heptane were dispatched to the participants. The participants were asked to determine the mineral oil content of the test samples by application of their in‐house analysis methods. In total, 55 sets of results were reported to the organisers of the study. The performance of laboratories was expressed by z‐scores for the oil samples and by relative bias for the mineral oil solution in n‐heptane. The percentage of successful laboratories in the determination of the mineral oil content of sunflower oil was for all sunflower oil test materials about 80%.

Effect of chain disentanglement on melt crystallization behavior of isotactic polypropylene

Isotactic polypropylene (iPP) with “disentangled” chains was generated through crystallization of iPP from its mineral oil solution. TGA test assured complete removal of mineral oil from iPP precipitates. Time sweep rheological measurements showed the modulus build-up with time indicating the formation of “disentangled” chains in iPP after the sample disentanglement treatment. The “disentangled” chains could preserve for a certain time before completely re-entangled during melting. Crystallization kinetics of iPP with “disentangled” chains was studied by using polarized optical microscope. The growth rate of spherulites in “disentangled” iPP was faster than that in the entangled one.