Mixture Of Mineral Oil Research Articles

Permeation of Mineral Oil Components from Cardboard Packaging Materials through Polymer Films

Mineral oil migration from cardboard packaging into foodstuffs is recognized as a serious problem for the consumers. Within this study, a fast automated method for the determination of mineral oil permeation through barrier films was developed. The method is using 15 defined standard substances representing mineral oil chemistry instead of complex mineral oil mixtures. The developed method can be used for the evaluation of the barrier properties for polymer films regarding mineral oil components from paper and cardboard packaging materials. For all investigated permeants and polymer films, the logarithm of the permeation rates and the logarithm of the vapour pressure result in a linear correlation. The correlation can be used to compare the permeation properties of different barrier films. From the results of this study, it can be concluded that 12 µm oriented polyethylene terephthalate or 15 µm oriented polyamide are effective barriers towards mineral oil components. The barrier effect of pure polyolefin films is negligibly poor because the permeation is too fast and the lag time is in the range of a few hours at 40°C. As a consequence, the migration of mineral oil components from cardboard can be significantly reduced if inner layers of good barrier materials such as polyethylene terephthalate or polyamide are used. Copyright © 2012 John Wiley & Sons, Ltd.

How much formalin is enough to fix tissues?

A total of sixty samples from human breast, uterus, liver, skin and abdominal fat were fixed for 8; 24 and 48 hours at a room temperature of 20 to 22°C with neutral buffered formalin (NBF) with volume to tissue ratios of 1:1; 2:1; 5:1 and 10:1 and manually processed with isopropyl alcohol and mineral oil mixtures. All the slides prepared were evaluated as suitable for diagnostic purposes by nine pathologists from three different Russian histopathology institutions. The microtomy quality differences between the samples was not statistically significant for the different fixation volume ratios tested, but the differences between fixation periods and tissues types were, with 48 hours being the optimum fixation period, with skin and fat the most difficult to infiltrate. Neither the time and volume ratio combinations affected the pH of NBF or the immunostaining for vimentin in uterus or the histochemical periodic acid reaction or reticular demonstration fibers in liver. Fixing tissues with a ratio of NBF volume to tissue volume of 2:1 for 48 hours at 20-22°C was enough to assure a proper fixation and infiltration of the tested tissues and there is no objective reason to expect that other tissues will not behave similarly. It is suggested that in order to obtain good fixation and paraffin wax infiltration in around 10 hours, the fixation with NBF at 2:1 should be at 45°C with pressure and agitation.

Removal of the vanadium impurities from crude TiCl4 with high content of vanadium using a mixture of Al power and white mineral oil

The purification of crude titanium tetrachloride (TiCl4) with vanadium impurities (mainly as VOCl3 and VCl4) was investigated by treatment with a mixture of Al powder and white mineral oil (WMO). L9 orthogonal array and analysis of variance (ANOVA) were applied to determine the optimal condition and most significant factors. In comparison with the conventional purification processes by adding WMO or Al powder alone, with WMO or Al powder as purification agent, the present process showed obvious advantages in saving the reaction time and improving the purification efficiency. Scanning electron microscopy coupled with energy dispersive spectroscopy (SEM-EDS) and X-ray photoelectron spectroscopy (XPS) were further used to measure the residue after purification. The results showed that VOCl3 was converted to insoluble VOCl2 by reduction of TiCl3 through the reaction of Al powder with TiCl4 and active carbon produced from the pyrolytic cracking of WMO.

Muscle sparing in muscle RING finger 1 null mice: response to synthetic glucocorticoids

Skeletal muscle atrophy occurs under a variety of conditions and can result from alterations in both protein synthesis and protein degradation. The muscle-specific E3 ubiquitin ligases, MuRF1 and MAFbx, are excellent markers of muscle atrophy and increase under divergent atrophy-inducing conditions such as denervation and glucocorticoid treatment. While deletion of MuRF1 or MAFbx has been reported to spare muscle mass following 14 days of denervation, their role in other atrophy-inducing conditions is unclear. The goal of this study was to determine whether deletion of MuRF1 or MAFbx attenuates muscle atrophy after 2 weeks of treatment with the synthetic glucocorticoid dexamethasone (DEX). The response of the triceps surae (TS) and tibialis anterior (TA) muscles to 14 days of DEX treatment (3 mg kg(-1) day(-1)) was examined in 4 month-old male and female wild type (WT) and MuRF1 or MAFbx knock out (KO) mice. Following 14 days of DEX treatment, muscle wet weight was significantly decreased in the TS and TA of WT mice. Comparison of WT and KO mice following DEX treatment revealed significant sparing of mass in both sexes of the MuRF1 KO mice, but no muscle sparing in MAFbx KO mice. Further analysis of the MuRF1 KO mice showed significant sparing of fibre cross-sectional area and tension output in the gastrocnemius (GA) after DEX treatment. Muscle sparing in the MuRF1 KO mice was related to maintenance of protein synthesis, with no observed increases in protein degradation in either WT or MuRF1 KO mice. These results demonstrate that MuRF1 and MAFbx do not function similarly under all atrophy models, and that the primary role of MuRF1 may extend beyond controlling protein degradation via the ubiquitin proteasome system.

Toward a Reliable Synthesis of Strontium Ruthenate: Parameter Control and Property Investigation of Submicrometer-Sized Structures

SrRuO3 (SRO) has been studied extensively at the bulk and thin film scales for a variety of applications, such as multilayer devices, field-effect devices, multiferroics, and even ferroelectric random access memory (FeRAM). Conversely, the exploration of SRO nanoscale and submicrometer scale structures in terms of both synthesis and applications has been significantly limited. Herein, we are the first to report on the synthesis of SRO submicrometer-sized particles via a molten-salt method. We have accomplished this by systematically probing experimental parameters such as precursors, type of salt, annealing time, annealing temperature, surfactant, cooling rate, and reaction atmosphere in an effort to predictably control the resulting size, shape, and morphology of the SRO product particles. In particular, by quenching the reaction at a cooling rate of 100 °C/min, we can produce rounded SRO particles averaging 149 ± 100 nm in size. Moreover, with the addition of a mixture of mineral oil in Triton X-100, the final SRO particles are highly faceted, single-crystalline octahedra, averaging 126 ± 45 nm in size. Apart from the choice of molten salt which primarily controls chemical composition of SRO, we have determined the most important experimental parameter for shape and aggregation control is the surfactant, because of a combination of its hydrophobic and hydrophilic characteristics. We have found that the decomposition of the surfactant promotes the formation of SrCO3, which is consistent with the generation of SRO through the reaction of SrCO3 with RuO2. Our successful syntheses have allowed us to explore physical properties, that is, magnetic and electronic, of these submicrometer-sized SRO particles, which are in good agreement with bulk SRO. Furthermore, we have also explored the potential of our as-synthesized particles as effective methanol oxidation reaction (MOR) catalysts for direct methanol fuel cells (DMFCs). Not only are our as-synthesized SRO particles MOR active but also our well-defined faceted octahedra exhibit a 4-fold increase in mass-activity and a 4-fold increase in surface area by comparison with the rounded particles, thereby emphasizing a clear advantage of faceted submicrometer SRO for electrochemical applications.

Property blending relationships for binary mixtures of mineral oil and elektrionised vegetable oil: viscosity, solvent power, and seal compatibility index

ABSTRACTThe present study provides quantitative data on the physicochemical properties of binary mixtures of a special class of bio‐based lubricity additives — elektrionised vegetable oils — with various classes of mineral base oils. A specific emphasis is placed upon viscosity blending relationships, solubility and seal compatibility. Experimental data are rationalised using appropriate theoretical models, which can be readily applied to property blending practice.It is shown that For elektrionised vegetable oil/mineral oil binary systems, viscosity blending calculations can be guided by using Roegiers or Grunberg–Nissan blending equations. The Roegiers equation works especially well for systems showing large deviation from ideal behaviour. Elektrionised vegetable oils can be used as mild solvency improvers for non‐conventional base oils produced by hydrocracking and isodewaxing technology or through gas‐to‐liquid conversion, Elektrion C (Elektrion s.a., Bruxelles, Belgium) being a more potent solvency improver than Elektrion R. Elektrionised vegetable oils demonstrate good seal compatibility in combination with various mineral basestocks. Copyright © 2011 John Wiley & Sons, Ltd.

Bioimpedance Changes in Rats with CCl4-Induced Liver Fibrosis

To characterize the relationship between the stage of hepatic fibrosis and bioimpedance, several electric parameters were estimated in rats with <TEX>$CCl_4$</TEX>-induced liver fibrosis. Thirty three Sprague-Dawley rats were intraperitoneally injected with a <TEX>$CCl_4$</TEX>-mineral oil mixture (1:1, 0.2 mL/100 g) twice a week for 8 weeks. The resistance(R), reactance(X), impedance(Z), and dissipation factor(D) between 1 kHz and 100 kHz were then evaluated in the livers of the rats under pentobarbital anesthesia using an HP4294A Impedance Analyzer. The rats were killed 2, 4, 6, and 8 weeks later, and their livers were classified in accordance with Ishak's scoring system. R, X, and Z changed in accordance with the progression of hepatic fibrosis and the changes were greater at lower frequencies than at higher frequencies. In comparison, the D spectrum was biphasic; D increased initially then decreased with increasing frequency. All of the parameters(R, X, Z, and D) changed in accordance with the stage of fibrosis in the livers, but D changed specifically with the progression of fibrosis. These results indicate that hepatic fibrosis may be evaluated by determining the changes in D.

Tribological Effects of Mineral-Oil Lubricant Contamination with Biofuels: A Pin-on-Disk Tribometry and Wear Study

Use of biodiesel produces engine oil dilution because of unburned biodiesel impinging on cold walls of the combustion chamber, being scrapped to the oil pan, and leading to changes of oil friction, wear and lubricity properties. In this paper, mixtures of SAE 15W-40 oil, which were contaminated by known percentages of the biodiesels from canola oil, peanut oil, soybean oil, and chicken fat, were tested in a pin-on-disk tribometer. A contact was employed of AISI 1018 steel disk and AISI 316 stainless-steel ball for pin material, and friction force and specific wear were measured. Wear on the disk surfaces showed that any degree of mineral-oil dilution by the tested biodiesels reduces the wear protection of engine oil even at small mixture percentages. However, these reductions were not substantially different than those observed for same percentages of dilution of mineral oil by fossil diesel. The tested mixture of oil contaminated with animal fat feedstock (e.g., chicken fat) biodiesel showed the best wear behavior as compared to those for the other tested mixtures (of mineral oil with vegetable feedstock biodiesel dilutions). Obtained results are discussed as baseline for further studies in a renewable energy multidisciplinary approach on biofuels and biolubes.

Development of Model Materials for Physical Forming Simulation of Metals and Alloys

In conjunction with experimental simulation of metal forming, the development of model materials, by which forming simulation can be carried out at a low stress level at room temperature, was performed. The model materials are mixtures of microcrystalline wax, rosin, mineral oil and powder. The flow curves of the model materials show three typical configurations, i.e., work-softening type, steady state deformation type and work-hardening type, which are observed in metals and alloys. The above configurations of the flow curves of the model materials could be changed and controlled by adjusting powder content. The flow curves of the model material could be predicted accurately using the work-hardening rate equation determined in this work. As an application example, experiments on and visio-plasticity analyses of the plane strain backward extrusion of magnesium alloy and its model material, which represent the deformation property of work-softening type materials, were carried out. We confirmed that the material flow and strain conditions in both materials correspond to each other with sufficient accuracy for engineering purpose.

New experimental method of visualizing the electric field due to surface charges on circuit elements

Although static surface charges on circuit elements are of enormous interest, recent papers and textbooks have only discussed the problem theoretically using analytical or numerical approaches. The only well-known experimental method to visualize the structure of electric fields around circuit elements was reported by Jefimenko almost half a century ago. In our paper, we report on a simple method to visualize the electric field produced by static surface charges on current-carrying circuit elements. Our method uses a mixture of PTFE (Teflon) sealant and mineral oil, a copper wire placed in the mixture’s container, and two 6 kV power supplies. We believe that our new method can be used directly in the classroom.

Optimisation of Cosolvent Concentration for Topical Drug Delivery III – Influence of Lipophilic Vehicles on Ibuprofen Permeation

Previously, we have reported the effects of water, ethanol, propylene glycol and various binary and ternary mixtures of these solvents on the permeation of ibuprofen in model membranes and in skin. The present study investigates the influence of lipophilic vehicles on the transport of ibuprofen in silicone membrane and in human skin. The permeation of ibuprofen was measured from mineral oil (MO), Miglyol® 812 (MG) and binary mixtures of MO and MG. The solubility of ibuprofen was 5-fold higher in MG than in MO, however, the permeation of ibuprofen from the pure vehicles and combinations of both was comparable in silicone membrane. Additionally, there were no significant differences in skin permeation for MO and MG vehicles. When the permeation of various hydrophilic and lipophilic vehicles is considered, a trend between flux values for the model membrane and skin is evident (r² = 0.71). The findings suggest that silicone membrane may provide information on qualitative trends in skin permeation for vehicles of diverse solubility and partition characteristics.

Drop Production and Tip-Streaming Phenomenon in a Microfluidic Flow-Focusing Device via an Interfacial Chemical Reaction

Microfluidic flow-focusing technology is used to investigate the effect on drop formation due to the production of a surfactant via an interfacial chemical reaction. The reactants are an aqueous solution of sodium hydroxide (NaOH) and a mixture of oleic acid (C(17)H(33)-COOH) and mineral oil, for the dispersed and continuous phase fluids, respectively, at concentration < or = 5 mM. In the absence of a chemical reaction, the drop shapes remain constant from just after breakup into droplets down at the flow-focusing nozzle until the drops exit the channel. In the presence of the chemical reaction, there is modification of the shape depending on the concentration of reactants. The drop speeds, O(10) mm/s, lengths, O(1-100) microm, and relative displacements, O(100-1000) microm, are measured for a variety of flow conditions with observable trends that correlate with the reaction rate, which we rationalize by using the Damkohler number to characterize drop production and transport in these types of flows.

Quantitative determination of phenol in natural decayed leaves using procaine modified carbon paste electrode surface by cyclic voltammetry

In this research, the amount of phenol in decayed leaves was quantified in aqueous medium by using procaine hydrochloride modified carbon paste electrode. Working electrode was prepared by using homogeneous mixture of graphite powder and mineral oil (80:20%). The mixture was pressed on the electrode surface thus a glassy form was obtained. The electrode surface was modified with procaine hydrochloride in 0.1 M tetrabutylammonium tetrafluoroborate using 100 mV s − 1 scanning rate between −1.7 V and −0.5 V with 50 cycles. After the modification process, the electron transfer becomes easier and faster. For the calibration curve, a series of standard phenol solution between 1.0 × 10 − 3 M and 1.0 × 10 − 8 M was prepared using Britton–Robinson buffer solution at pH 12. The prepared standard solutions were used for the chemical binding of phenol to the modified electrode surface between 0.0 V and + 0.9 V potential range using 100 mV s − 1 scanning rate with 10 cycles. Calibration curve was obtained by plotting concentrations versus peak currents of standard phenol solutions. By using this calibration method, the amount of phenol was determined as 8.33 × 10 − 5 M in natural decayed leaves in BR buffer solution at pH 12. Detection limit was obtained as low as 1.0 × 10 − 8 M.

Physical modelling of pile penetration in clay using transparent soil and particle image velocimetry

A small-scale physical modelling method was developed to study the movement of clay during pile installation. The clay was simulated using a mixture of amorphous silica and mineral oil, which becomes almost transparent when the refractive indices of the oil and the silica are well matched. After adding reflective particles and consolidating the mixture in a transparent container, cylindrical model piles were driven vertically at the centre. A vertical section aligned with the pile centreline was illuminated by a laser light sheet, and a sequence of digital images was recorded. These were analysed using particle image velocimetry, and the complete displacement distribution during the pile installation was obtained. Notwithstanding some discrepancies at shallow depths, the observed displacements generally showed fairly good agreement with the theoretical predictions of the shallow strain path method (SSPM) once the effect of some soil trapped beneath the flat pile tip was taken into account. Normalisation of the horizontal and vertical components of movement employing both the pile length and radius, based on SSPM theory, was shown to be valid. The normalised vertical displacement contours were similar to those published by previous researchers. The results of this study could be used to assess the impact of disturbance due to pile installation on, for example, buried services or archaeology.

Crystal Structures of Progressive Ca2+ Binding States of the Ca2+ Sensor Ca2+ Binding Domain 1 (CBD1) from the CALX Na+/Ca2+ Exchanger Reveal Incremental Conformational Transitions

Na+/Ca2+ exchangers (NCX) constitute a major Ca2+ export system that facilitates the re-establishment of cytosolic Ca2+ levels in many tissues. Ca2+ interactions at its Ca2+ binding domains (CBD1 and CBD2) are essential for the allosteric regulation of Na+/Ca2+ exchange activity. The structure of the Ca2+-bound form of CBD1, the primary Ca2+ sensor from canine NCX1, but not the Ca2+-free form, has been reported, although the molecular mechanism of Ca2+ regulation remains unclear. Here, we report crystal structures for three distinct Ca2+ binding states of CBD1 from CALX, a Na+/Ca2+ exchanger found in Drosophila sensory neurons. The fully Ca2+-bound CALX-CBD1 structure shows that four Ca2+ atoms bind at identical Ca2+ binding sites as those found in NCX1 and that the partial Ca2+ occupancy and apoform structures exhibit progressive conformational transitions, indicating incremental regulation of CALX exchange by successive Ca2+ binding at CBD1. The structures also predict that the primary Ca2+ pair plays the main role in triggering functional conformational changes. Confirming this prediction, mutagenesis of Glu455, which coordinates the primary Ca2+ pair, produces dramatic reductions of the regulatory Ca2+ affinity for exchange current, whereas mutagenesis of Glu520, which coordinates the secondary Ca2+ pair, has much smaller effects. Furthermore, our structures indicate that Ca2+ binding only enhances the stability of the Ca2+ binding site of CBD1 near the hinge region while the overall structure of CBD1 remains largely unaffected, implying that the Ca2+ regulatory function of CBD1, and possibly that for the entire NCX family, is mediated through domain interactions between CBD1 and the adjacent CBD2 at this hinge.

Long-term Use of Antegrade Continence Enema

Source: Yardley IE, Pauniaho S, Baillie CT, et al. After the honeymoon comes divorce: long-term use of the antegrade continence enema procedure. J Pediatr Surg.2009;44(5):1274–1277; doi:10.1016/j.jpedsurg.2009.02.030The antegrade continence enema (ACE) procedure involves the construction of an abdominal wall stoma using the appendix as the conduit from the skin level in the right lower quadrant into the cecum; this allows access for antegrade irrigations on a regular and scheduled basis to provide effective colonic washout in patients with refractory chronic constipation. Investigators from Alder Hey Children’s Hospital in Liverpool, England, sought to determine the long-term use of ACE. All children who had an ACE at a single tertiary care center between 1993 and 1997 were surveyed to determine if they were still using the ACE and, if not, why use had been discontinued.Of the 84 eligible patients, 61 could be contacted. The mean age was 22.4 years (15–35 years) with an average follow-up time of 11 years (8–14 years). Their underlying diagnoses included spina bifida (27), anorectal malformation (18), intractable constipation (11), sacral agenesis (2), trauma or tumor (2), and Hirschsprung’s Disease (1). Thirty-six of the 61 patients (59%) were still using their ACE. In those patients continuing to use their ACE, the overall satisfaction score was 4 (on a scale of 1 to 5, with 5 being very satisfied).Among the 25 patients (41%) who reported discontinuing use of their ACE, 14 stated they had done so because the washouts had proven ineffective for prevention of soiling. Five others described significant pain with washouts, stomal stenosis, or difficulty in using the stoma during pregnancy. Two patients stopped using the ACE because of psychological issues, one because of being disturbed at the appearance of the stoma and one secondary to depression. Two additional patients were unable to comply with the washout regimen, rendering the ACE ineffective. There was no association between diagnosis and non-use. Several individuals reported feeling abandoned on becoming adults and losing the support they had in childhood.The authors conclude that patients discontinue use of the ACE for a variety of reasons and suggest that newer refinements of the surgical procedure may lead to its greater long-term successful use. Most concerning, however, is the high level of discontent with the transitional care arrangements on reaching adulthood.Dr Cavett has disclosed no financial relationship relevant to this commentary. This commentary does not contain a discussion of an unapproved/investigative use of a commercial product/device.The ACE allows the patient to receive effective colonic irrigation via the right colon, thereby promoting cleanout of the entire colon at one time. The colon can then serve as a large reservoir for stool, permitting absence of soiling during the day. The usual regimen involves a mixture of water and either mineral oil or glycerin in volumes and concentrations necessary to obtain washout results.The principal complication of this procedure is painful catheter insertion as a result of stomal stenosis. Mucus leak can be a problem but this is usually temporary during the first several weeks following the surgery. Several changes in the washout regimen are usually necessary before a steady state is reached.2The operation is not terribly complicated and involves constructing a stoma via the tip of the still-attached appendix. An anti-refluxing wrap of cecal wall around the base of the appendix can usually prevent fecal reflux. Much attention must be paid to construction of the stoma itself, interdigitating skin and opened appendiceal lumen in such a way as to allow easy catheterization, yet it must remain fairly flat and dry of mucus.3This group report denotes two important points for surgeons and pediatricians alike. First, we have a good tool available to us when patients need this level of colon washout which cannot be managed with rectal irrigations, and would benefit from an intervention that offers some degree of social acceptance. Second, we must endeavor to provide seamless care as patients with lifelong problems move into the adult world of health care. These patients require ongoing support and care if maintaining continence is to be effective.

Época e princípios ativos para a quebra de dormência de caquizeiro cv. Fuyu

Este trabalho foi realizado com o objetivo de aumentar o período de oferta do caqui 'Fuyu' e buscar alternativas à falta de opções para estimular a brotação, avaliando-se épocas e diferentes princípios ativos na quebra de dormência dos frutos. Os tratamentos testados foram: óleo mineral (OM), cianamida hidrogenada (CH) e a mistura de macro e micronutrientes, em três épocas de aplicação, constituindo-se esquema fatorial com 5 tratamentos e 3 épocas de aplicação. Os tratamentos testados foram: T1-testemunha; T2- 0,5 % OM; T3-: 2 % CH + 0,5 % OM; T4- 1 % micronutrientes + 0,2 % macronutrientes + 0,5 % OM; T5- 2 % micronutrientes + 0,2 % macronutrientes + 0,5 % OM. Avaliaram-se o número de brotos por ramo, a porcentagem de gemas brotadas e o número de ramos com broto, o número e a produção de frutos por planta. A antecipação da época de quebra de dormência provocou a diminuição do número de frutos produzidos na região centro-sul do Paraná. A produção de frutos foi diretamente proporcional à porcentagem de gemas brotadas no primeiro surto de brotação. A aplicação de cianamida hidrogenada promoveu antecipação da brotação e aumento na produção de frutos de caquizeiro; no entanto, a mistura de micronutrientes e óleo mineral não influenciou na brotação e produção de frutos de caquizeiro.

Copolymer-in-oil Phantom Materials for Elastography

Phantoms that mimic mechanical and acoustic properties of soft biological tissues are essential to elasticity imaging investigation and to elastography device characterization. Several materials including agar/gelatin, polyvinyl alcohol and polyacrylamide gels have been used successfully in the past to produce tissue phantoms, as reported in the literature. However, it is difficult to find a phantom material with a wide range of stiffness, good stability over time and high resistance to rupture. We aim at developing and testing a new copolymer-in-oil phantom material for elastography. The phantom is composed of a mixture of copolymer, mineral oil and additives for acoustic scattering. The mechanical properties of phantoms were evaluated with a mechanical test instrument and an ultrasound-based elastography technique. The acoustic properties were investigated using a through-transmission water-substituting method. We showed that copolymer-in-oil phantoms are stable over time. Their mechanical and acoustic properties mimic those of most soft tissues: the Young's modulus ranges from 2.2–150 kPa, the attenuation coefficient from 0.4–4.0 dB.cm –1 and the ultrasound speed from 1420–1464 m/s. Their density is equal to 0.90 ± 0.04 g/cm 3. The results suggest that copolymer-in-oil phantoms are attractive materials for elastography. (E-mail: jennifer.oudry@echosens.com)

Effect of α-tocopherol on carbon tetrachloride intoxication in the rat liver

Carbon tetrachloride (1 ml/kg body weight as a 1:1 mixture of CCl(4) and mineral oil) was orally administered to rats. After 12 h, the activity of plasma ALT (alanine aminotransferase) was significantly higher than that of the control group, and plasma ALT and AST (aspartate aminotransferase) activities significantly increased 24 h after CCl(4) administration. These results indicated that the necrotic process had initiated at about 12 h and developed thereafter. After 6-24 h of CCl(4) administration, the hepatic level of vitamin C, the most sensitive indicator of oxidative stress, decreased significantly, indicating that oxidative stress was significantly enhanced 6 h after CCl(4) intoxication and thereafter. Oral administration of vitamin E (1 ml/kg body weight as a 1:1 mixture of alpha-tocopherol and mineral oil) 12 h before CCl(4) administration caused a significant elevation of liver vitamin E level and ameliorated liver necrosis 24 h after CCl(4) intoxication based on plasma AST and ALT. Vitamin E also significantly restored the hepatic vitamin C concentration 12 and 24 h after CCl(4) intoxication, demonstrating that vitamin E functioned as an antioxidant. The liver vitamin E concentration was not changed by vitamin E supplementation to rats that did not receive CCl(4). This result indicated that vitamin E accumulated in the damaged liver. The activation of JNK, ERK1/2 and p38 MAPK took place 1.5 h after CCl(4) administration. Co-administration of alpha-tocopherol with CCl(4) did not affect these early changes in MAPKs.

An Experimental Study on Wax Removal in Pipes With Oil Flow

Pigging is recognized as one of the most used techniques for removing wax deposits in pipelines. In an earlier paper, the mechanics of wax removal was studied using an experimental setup under dry conditions, i.e., no oil presence. In this study, the pigging experiments are conducted for both regular disk and by-pass disk pigs under flowing conditions. A new test facility was designed and constructed. The test section is 6.1 m (20 ft) long schedule 40 steel pipe with an inner diameter of 0.0762 m (3 in.). A mixture of commercial wax and mineral oil is cast inside the spool pieces for different wax thicknesses and oil contents. The wax breaking and plug transportation forces are investigated separately. The results indicated that the wax breaking force increases as wax thickness increases, and the wax plug transportation force gradient is independent of the wax plug length. In comparison to previous test results, the presence of oil reduced the wax plug transportation force. Experimental results also showed that the wax transport behavior of the by-pass pig is significantly different than that of the regular pig. The by-pass pig allows the oil to flow through the by-pass holes and mobilizes the removed wax in front of the pig resulting in no discernible wax accumulation in front of the pig. Therefore, no measurable transportation force was observed for the by-pass pig tests.