Showing papers on "Liquid paraffin published in 2015"

Ultrathin MoS2 Nanosheets with Superior Extreme Pressure Property as Boundary Lubricants.

Abstract: In this paper, a new kind of oil-soluble ultrathin MoS2 nanosheets is prepared through a one-pot process. A superior extreme pressure property, which has not been attained with other nano-additives, is discovered when the nanosheets are used as lubricant additives. The as-synthesized MoS2 nanosheet is only a few atomic layers thick and tens of nanometers wide, and it is surface-modified with oleylamine so it can be well dispersed in oil or lubricant without adscititious dispersants or surfactants. By adding 1 wt% ultrathin MoS2 nanosheets, at the temperature of 120 °C, the highest load liquid paraffin can bear is tremendously improved from less than 50 N to more than 2000 N. Based on the tribological tests and analysis of the wear scar, a lubrication mechanism is proposed. It is believed that the good dispersion and the ultrathin shape of the nanosheets ensure that they can enter the contact area of the opposite sliding surfaces and act like a protective film to prevent direct contact and seizure between them. This work enriches the investigation of ultrathin MoS2 and has potential application in the mechanical industry.

Organogel as durable anti-icing coatings

Abstract: A durable organogel anti-icing material via swelling cross-linked poly(dimethylsiloxane) with liquid paraffin is reported. The surface of the organogel is covered by a thin released layer of paraffin due to the osmotic pressure, which acts as a lubricant and reduces the ice adhesion greatly. Results show that the ice adhesion on the surface of the organogel is as small as 1.7±1.2 kPa (at −30°C) and the low ice adhesion remains even when the temperature is lowered to −70°C. The surface with lubricating liquid paraffin layer exhibits excellent durability, as it shows an ultralow ice adhesion after 35 cycles of icing/deicing and 100 days of exposure in ambient environment.

Doped quantum dot@silica nanocomposites for white light-emitting diodes

Abstract: This work reports the use of a near-UV-LED chip in combination with blue, green-yellow and red emitting doped ZnSe QD@silica nanocomposites to construct a novel WLED with reduced scattering and no reabsorption. Blue, green-yellow and red emitting Cu or Mn doped ZnSe QDs with enlarged Stokes shifts and similar absorption peaks (360–410 nm) were synthesized in liquid paraffin in order to solve the reabsorption problem and also obtain balanced white emission spectra. Silica shells were then coated onto the doped QDs, allowing for the refractive index of the nanocomposites to be tailored while simultaneously improving their compatibility with the epoxy resin. The transparent doped ZnSe QD@SiO2/epoxy composite was then used as a light conversion and encapsulant material in combination with the near-UV-LED chip to fabricate the WLED. This fabricated WLED demonstrated high luminous efficiency and good color chromatics stability, suggesting that WLEDs based on highly fluorescent doped ZnSe QD@silica nanocomposites in combination with near-UV-LED chips may prove to be promising candidates for alternative light sources.

Laxatives for the management of constipation in people receiving palliative care

Abstract: BACKGROUND: This article describes the second update of a Cochrane review on the effectiveness of laxatives for the management of constipation in people receiving palliative care. Previous versions were published in 2006 and 2010 where we also evaluated trials of methylnaltrexone; these trials have been removed as they are included in another review in press. In these earlier versions, we drew no conclusions on individual effectiveness of different laxatives because of the limited number of evaluations. This is despite constipation being common in palliative care, generating considerable suffering due to the unpleasant physical symptoms and the availability of a wide range of laxatives with known differences in effect in other populations. OBJECTIVES: To determine the effectiveness and differential efficacy of laxatives used to manage constipation in people receiving palliative care. SEARCH METHODS: We searched the Cochrane Central Register of Controlled Trials (CENTRAL; The Cochrane Library), MEDLINE, EMBASE, CINAHL and Web of Science (SCI & CPCI-S) for trials to September 2014. SELECTION CRITERIA: Randomised controlled trials (RCTs) evaluating laxatives for constipation in people receiving palliative care. DATA COLLECTION AND ANALYSIS: Two authors assessed trial quality and extracted data. The appropriateness of combining data from the studies depended upon clinical and outcome measure homogeneity. MAIN RESULTS: We identified five studies involving the laxatives lactulose, senna, co-danthramer, misrakasneham, docusate and magnesium hydroxide with liquid paraffin. Overall, the study findings were at an unclear risk of bias. As all five studies compared different laxatives or combinations of laxatives, it was not possible to perform a meta-analysis. There was no evidence on whether individual laxatives were more effective than others or caused fewer adverse effects. AUTHORS' CONCLUSIONS: This second update found that laxatives were of similar effectiveness but the evidence remains limited due to insufficient data from a few small RCTs. None of the studies evaluated polyethylene glycol or any intervention given rectally. There is a need for more trials to evaluate the effectiveness of laxatives in palliative care populations. Extrapolating findings on the effectiveness of laxatives evaluated in other populations should proceed with caution. This is because of the differences inherent in people receiving palliative care that may impact, in a likely negative way, on the effect of a laxative.

Synthesis and tribological properties of oil-soluble copper nanoparticles as environmentally friendly lubricating oil additives

Abstract: Purpose – The purpose of this paper is to synthesize oil-soluble copper (Cu) nanoparticles modified with free phosphorus and sulfur modifier and investigate its tribological properties as environment-friendly lubricating oil additives. Design/methodology/approach – To improve the anti-oxidation properties of these nanoparticles, two kinds of surface modifiers, oleic acid and oleylamine were used simultaneously. The morphology, composition, structure and thermal properties of as-synthesized Cu nanoparticles were investigated by means of transmission electron microscopy, X-ray powder diffraction, Fourier transform infrared spectrometry and differential thermal and thermogravimetric analysis. The tribological properties of as-synthesized Cu nanoparticles as an additive in liquid paraffin were evaluated with a four-ball friction and wear tester. Findings – It has been found that an as-synthesized Cu nanoparticle has a size of 2-5 nm and can be well dispersed in organic solvents. Tribological properties evalua...

Sustainable and hydrolysis-free dyeing process for polylactic acid using nonaqueous medium

Abstract: A sustainable and hydrolysis-free dyeing process was developed for polylactic acid (PLA) fibers. PLA is a biobased alternative to petroleum based polyethylene terephthalate (PET), which is the most widely used textile fiber. However, the hydrolytic degradation of PLA fibers under the conventional aqueous dyeing conditions limited its applications in textile industry. A new solvent dyeing process was developed using liquid paraffin as a nonaqueous dyeing medium. High quality dyed PLA fabrics were obtained without consuming water and auxiliaries. Minimal strength loss of dyed fibers was achieved by postheat setting treatment. The 3R principle (reduce, reuse, and recycle) was implemented to ensure the environmental friendliness of solvent dyeing process. The result of a 9-cycle reuse sequence demonstrated excellent color consistency of dyed PLA fabrics. The sustainability of our new dyeing process was quantified in the framework of environmental-health-social impact. The dyeing process sustainability index i...

Continuous generation of alginate microfibers with spindle-knots by using a simple microfluidic device

Abstract: We developed a simple microfluidic-based method to fabricate calcium alginate microfibers with spindle-knots A co-axial type microfluidic device installed with a micropipette at its outlet was used with a sodium alginate solution as the continuous phase and liquid paraffin as the dispersed phase We examined the effect of the micropipette, its diameter, the dispersed phase to the continuous phase flow rate ratio and the physical properties of the oil used as the dispersed phase on the formation of the knots, the width and height of the knot, the interval between two adjacent knots, and the diameter of the fiber Use of the micropipette is crucial to successful formation of the knots, as the oil phase microdroplets are deformed when flowing through it and retract after flowing out of it The height and width of the knot increase and the interval decreases with increasing the flow rate ratio and the microdroplet diameter The viscosity of the oil phase plays an important role in the successful formation of the knots The alginate fibers with spindle-knots exhibit water collection capability This method is expected to be used for the fabrication of other types of fibers with spindle-knots

The role of oxidative stress on carotene production by Blakeslea trispora in submerged fermentation.

Abstract: In aerobic metabolism, reactive oxygen species (ROS) are formed during the fermentation that can cause oxidative stress in microorganisms. Microbial cells possess both enzymatic and non-enzymatic defensive systems that may protect cells from oxidative damage. The antioxidant enzymes superoxide dismutase and catalase are the two key defensive enzymes to oxidative stress. The factors that induce oxidative stress in microorganisms include butylated hydroxytoluene (BHT), hydrogen peroxide, metal ions, dissolved oxygen tension, elevated temperature, menadione, junglone, paraquat, liquid paraffin, introduction to bioreactors of shake flask inocula and synthetic medium sterilized at initial pH 11.0. Carotenes are highly unsaturated isoprene derivatives. They are used as antioxidants and as coloring agents for food products. In fungi, carotenes are derived via the mevalonate biosynthesis pathway. The key genes in carotene biosynthesis are hmgR, ipi, isoA, carG, carRA and carB. Among microorganisms, Βlakeslea trispora is the main microorganism used for the production of carotenes on the industrial scale. Currently, the synthetic medium is considered the superior substrate for the production of carotenes in a pilot plant scale. The fermentation systems used for the production of carotenes include shake flasks, stirred tank fermentor, bubble column reactor and flat panel photobioreactor. This review summarizes the oxidative stresses in microorganisms and it is focused on the current status of carotene production by B. trispora including oxidative stress induced by BHT, enhanced dissolved oxygen levels, iron ions, liquid paraffin and synthetic medium sterilized at an initial pH 11.0. The oxidative stress induced by the above factors increases significantly the production of carotenes. However, to further reduce the cost of carotene production, new biotechnological methods with higher productivity still need to be explored.

Preparation and tribological properties of organically modified graphite oxide in liquid paraffin at ultra-low concentrations

Abstract: In recent years, two-dimensional (2-D) materials have attracted more and more attentions due to their 2-D anisotropy and special physicochemical properties. In this work, hexadecyltrimethoxysilane (HDTMS) and octyltrimethoxysilane (OTMS) were employed to modify graphite oxide (GO) nanosheets for potential applications as lubricating oil additives. The organically modified GO nanosheets were characterized by FTIR, XRD, TGA, UV-vis spectroscopy and SEM, which indicated that HDTMS and OTMS had successfully entered the GO layers. Furthermore, the tribological properties of liquid paraffin containing HDTMS and OTMS modified GO were investigated by a four-ball friction testing machine. The results show that ultra-low concentration (0.008 wt%, the optimal value) of HDTMS or OTMS modified GO in liquid paraffin can reduce the friction coefficients of the mixtures by 34.0% and 15.5% respectively. HDTMS, which possesses longer alkyl chains, is better for improving the organic compatibilities and helps GO nanosheets to exfoliate more significantly and disperse in paraffin more homogeneously, thus corresponding to better effectiveness in decrease the friction coefficient.

Multilayer Three-Dimensional Structure Made of Modified Stainless Steel Mesh for in Situ Continuous Separation of Spilled Oil

Abstract: A multilayer three-dimensional (3D) structure made of hydrophobic stainless steel mesh has been designed for in situ continuous oil/water separation. The hydrophobic stainless steel mesh was prepared via a facile and environmental friendly method by etching with FeCl3 solution and coating with n-octadecylthiol. The as-prepared mesh allows oils (gasoline, diesel oil, engine oil) and organic solvents (hexane, liquid paraffin) to pass through and repels water. A separation device equipped with the multilayer 3D structure can continuously separate the aforementioned oils from oil–water mixtures. The separation efficiency of continuous separation is more than 99.0 wt % and shows little decrease after 10 cycles.

Extraction of Ce(IV) from sulphuric acid solution by emulsion liquid membrane using D2EHPA as carrier

Abstract: In order to provide a potential method for extracting Ce(IV), the extraction of Ce(IV) from sulphuric acid solution by an emulsion liquid membrane using D2EHPA as a carrier was investigated. The ELM system consisted of sulfonated kerosene as diluent, Span 80 as surfactant, liquid paraffin as intensifier and hydrochloric acid containing hydrogen peroxide as the inner aqueous solution. The influences of various parameters on the extraction of Ce(IV) were investigated. The optimum conditions for Ce(IV) extraction can be summarized as follows: D2EHPA concentration, 12% (v/v); Span 80 concentration, 2–3% (v/v); liquid paraffin concentration, 2–4% (v/v); hydrochloric acid concentration in the internal phase, 4–5 mol l−1; hydrogen peroxide concentration, 0.02 mol l−1; volume ratio of membrane phase to internal phase (Roi), 1.5; external phase acidity, 0.4–0.5 mol l−1; volume ratio of external phase to membrane phase (Rwe), 2; extraction time, 15 min; and stirring speed, 250 rpm. Experiments in which Ce(IV) was separated from RE(III) were then carried out under the optimum conditions, and the results indicated that the system is extremely selective for Ce(IV). The mechanism of Ce(IV) extraction has also been discussed. The loss for the experimental process was within 3%. The results reveal that the ELM method is a clean and cost-effective process for the extraction of Ce(IV) from sulphuric acid solution.

Effect of Some Levels of Cardamom, Clove and Anise on Hepatotoxicity in Rats Caused by CCL 4

Abstract: The aim of this study was to investigate the effect of three levels of cardamom, clove and anise on rats suffering from hepatotoxicity. Fifty five male albino rats (Sprague Dawley Strain) used in this study, the rats divided into eleven groups. The first and second groups fed on basal diet as a control negative and positive groups. The third, fourth and fifth groups were fed on basal diet containing (2%, 4% and 6% cardamom, respectively), the sixth, seventh and eighth groups were fed on basal diet containing (2%, 4% and 6% clove, respectively), the ninth, tenth and eleventh groups were fed on basal diet containing (2%, 4% and 6% anise, respectively). On the 27 day of the experiment, all animals, except the negative control group was administered subcutaneous injection 20% CCl in liquid paraffin oil at a dose 5 ml/kg body weight to induce 4 hepatotoxicity in rats. During the experimental period (28 days), the diets consumed and body weights were recorded twice weekly, at the end of the experiment period, the rats were fasted overnight, then the rats were anaesthetized and sacrificed and the blood samples were collected from the aorta. The blood samples were centrifuged and serum was separated to determine some biochemical parameters. Results showed that, feeding rats on basal diet and injected with CCl (control positive group) induced non-significant changes in 4 fed intake and body weight gain %, while liver and kidney weights, liver enzymes, lipid profile, except HDL-c, glucose and kidney functions increased significantly increase p?0.5, as compared to the rats fed on basal diet in the first main group (control negative group). Treating rats which suffer from hepatotoxicity with the three levels from (cardamom, clove and anise) decreased body weight gain%, liver and kidney weights/body weight%, serum AST, ALT, ALP, cholesterol, triglycerides, LDL-c, VLDL-c, uric acid, urea nitrogen, creatinine, glucose, while HDL-c increased. The highest improvement in these parameters recorded for the group which treated with the high level of clove (6%). In conclusion, the results of this study demonstrate that clove, cardamom and anise increased antioxidant activity and improved hepatotoxicity of rats.

Anti-wrinkle eye cream and preparation method thereof

Abstract: The invention belongs to the technical field of cosmetics, and particularly relates to an anti-wrinkle eye cream and a preparation method thereof The anti-wrinkle eye cream is prepared from the following raw materials: liquid paraffin, glycerinum, propylene glycol, polydimethylsiloxane, caprylic acid/capric triglyceride, a glycerol acrylate/acrylic copolymer, cetostearyl alcohol, PEG-20 methl glucse sesquistearate, C20-22 alcohol phosphate, a PVM/MA copolymer, hydroxyethylurea, nicotinamide, polyacrylamide, methl glucse sesquistearate, a lactobacillus/balausta fermented product extract, arctic alidrys siliquosa essence, starfish essence, a radix ophiopogonis extract, a watercress extract, hydrolyzed rice protein, butyrospemum parkii, carbomer, triethanolamine and the like The anti-wrinkle eye cream is good in permeability and easy to absorb; the elasticity of eye week skin is enhanced; the dryness and relaxation phenomena are improved; the damaged cells or the cells in nutrient deficiency are repaired; the skin aging is obviously delayed; the eye week skin restores into fullness and roundedness; and bright and shining eyes are regained

Interfacial and emulsifying properties of soybean peptides with different degrees of hydrolysis.

Abstract: In this study, the effects of the degree of hydrolysis on the interfacial and emulsifying properties of soybean peptides were evaluated based on surface and interfacial tension, dynamic light scattering (DLS), and freeze-fracture transmission electron microscopy (FF-TEM) analyses. Of the five evaluated soybean peptides (SP95, SP87, SP75, SP49, and SP23), those with higher degrees of hydrolysis (SP95 and SP87) did not exhibit noticeable surface-active properties in water, whereas those with relatively low degrees of hydrolysis (SP75, SP49, and SP23) exhibited remarkable surface tension-lowering activity. The latter set (SP75, SP49, and SP23) also formed giant associates with average sizes ranging from 64.5 nm to 82.6 nm above their critical association concentration (CAC). Moreover, SP23 with the lowest degree of hydrolysis exhibited excellent emulsifying activity for soybean oil, and FF-TEM analysis demonstrated that the emulsions were stabilized by a lamella-like multilayer peptide structure on the oil droplets that prevented coagulation. The peptide with the lowest degree of hydrolysis (SP23) was effective not only for soybean oil emulsification, but also for the emulsification of liquid paraffin and silicon oil that are generally difficult to emulsify.

Preparation of monodispersed CuS nanocrystals in an oleic acid/paraffin system

Abstract: Well-dispersed CuS nanocrystals were synthesized through a simple hot injection approach using cupric oxide and elemental sulfur as the precursors in an oleic acid/liquid paraffin system. The structural, morphological and optical properties of the as-prepared nanocrystal CuS samples were characterized by transmission electron microscopy, X-ray diffraction, X-ray photoelectron spectroscopy, ultraviolet-visible and near-infrared spectrophotometry, and room-temperature photoluminescence (RT-PL). The band gap of the CuS samples were estimated from the ultraviolet-visible spectra. The formation mechanism of monodispersed CuS nanocrystals in an oleic acid/liquid paraffin system was proposed. The cleaning agents have an important influence on the final morphology of the CuS nanocrystals, and pure hexagonal covellite CuS NCs can be obtained by controlling the ratio of Cu2+ : S2− = 1 : 1. The as-prepared CuS nanocrystals with the narrow band gap reveal dramatically broad absorption bands in the visible-light and near-infrared (NIR) region, exhibiting promising applications in photovoltaic cells, electrochemical sensors and photocatalysts.

Fabrication of pH sensitive microcapsules using soft templates and their application to drug release

Abstract: A method based on soft templates for pH sensitive microcapsule fabrication was developed using a layer-by-layer assembly technique. Toluene-in-water emulsion droplets were first stabilized by a surfactant sodium dodecyl benzene sulfonate (SDBS). Poly(diallyldimethyl ammonium chloride) modified latex beads were then adsorbed onto the droplet surfaces to make the emulsion more rigid. PSS (poly(sodium 4-styrenesulfonate))/PDDA (poly(diallyldimethyl ammonium chloride)) was assembled alternately onto the emulsion surface to form the microcapsules. Zeta potential analyzer, scanning electron microscopy (SEM), transmission electron microscopy (TEM), FT-IR, and fluorescence microscopy were used to characterize the samples. The toluene droplet templates were removed by ethanol upon heating. Fluorescein, as the water-soluble model drug, was loaded into the microcapsules. Its release behaviors were investigated as a function of wall thickness and pH. The maximum release percentage 61% was obtained after 36 hours at 37 °C at pH 7 with one double layer capsule. The capsule itself is nontoxic, while 5-fluorouracil (5-FU) loaded capsules killed 64.18% SK-RC-2 cells at a concentration of 17 μM at pH 7, which shows the great potential of this type of microcapsule in cancer chemotherapy. Olive oil and liquid paraffin were used to replace the toluene for forming soft templates in order to obtain microcapsules which are suitable for loading hydrophobic drugs. Sudan-1 was chosen as a hydrophobic model drug and 25% release was obtained after 36 hours at 37 °C.

The effects of sesame oil on the prevention of amiodarone-induced phlebitis.

Abstract: Background: Phlebitis is the most common complication associated with peripheral intravenous infusion of amiodarone. The purpose of this study is to determine the effects of sesame oil on the prevention of amiodarone‑induced phlebitis. Materials and Methods: This is a double‑blind randomized controlled trial. Thirty‑six patients hospitalized in a coronary care unit were randomly allocated into two groups using a convenience sampling method. Following peripheral intravenous cannulation, five drops of pure sesame oil were applied to the skin within a 10 cm radius of the infusion site prior to the administration of amiodarone in the intervention group. Sesame oil was rubbed on the skin at the infusion site every 6 h in the 24‑h period of amiodarone infusion. In the control group, liquid paraffin, used as a placebo, was rubbed on the skin at the infusion site of amiodarone. Both groups were monitored for the development of phlebitis and its degree within the 24‑h period of amiodarone infusion as well as 6 h after its administration. The incidence of phlebitis was confirmed and recorded by an assessor who was blind to the two groups. Data were analyzed using Statistical Package for Social Science (SPSS) version 18, and descriptive and inferential statistics such as Chi‑square test, Kaplan–Meier, Hazard ratio, independent t‑test, and Fisher’s exact test. Results: There was a statistically significant difference between the two groups in their catheter survival after 30 h and 10 min (P < 0.001). Over 60% of the patients (61.1%) in the intervention group did not show any sign of phlebitis, while 16.7% and 22.2% of the patients manifested signs of grade 2 and 3 phlebitis, respectively. In the control group, 22.2% of the patients showed no signs of phlebitis, while 5.6%, 27.8%, and 44.4% of the patients exhibited signs of grade 2, 3, and 4 phlebitis, respectively. The statistical analysis showed significant differences in the degree of phlebitis (P = 0.006) and the onset of phlebitis development (P < 0.001) between the two groups. Conclusions: It is recommended to apply sesame oil topically to the infusion site of amiodarone so as to reduce the rate of the development of amiodarone‑related phlebitis. Key words: Amiodarone, Iran, phlebitis, sesame oil

Modified fluororubber sealing gasket used for engine and preparation method of modified fluororubber sealing gasket

Abstract: The invention discloses a modified fluororubber sealing gasket used for an engine. The modified fluororubber sealing gasket comprises, by weight, 50-70 parts of maleic anhydride modified fluororubber, 20-30 parts of polyether urethane rubber, 10-20 parts of polypropylene, 5-15 parts of methyl vinyl silicone rubber, 1-3 parts of titanate coupling agents TMC-TTS, 0.8-1.6 parts of dicumyl peroxide, 1-3 parts of potassium peroxodisulfate, 1-3 parts of 2-thiol group benzimidazole, 5-8 parts of magnesium hydrate, 20-30 parts of polytetrafluoroethylene fiber, 5-10 parts of carbon fiber, 5-10 parts of ceramic fiber, 5-15 parts of white carbon black, 8-17 parts of talcum powder, 1-3 parts of anti-ageing agents, 1-3 parts of triphenyl phosphate, 1-3 parts of dibutyl phthalate, 1-2 parts of stearic acid, 0.5-1.5 parts of liquid paraffin and 1-3 parts of naphthenic oil. The invention further discloses a preparation method of the modified fluororubber sealing gasket. The product has good shock absorption performance and a good mechanical property, and the preparation method is simple.

Rosmarinus officinalis L. extract and some of its active ingredients as potential emulsion stabilizers: a new approach to the formation of multiple (W/O/W) emulsion.

Abstract: Nowadays, novel topical formulations loaded with natural functional actives are under intense investigations. Therefore, the aim of our study was to evaluate how the rosemary extract and some of its active ingredients [rosmarinic acid (RA), ursolic acid (UA) and oleanolic acid (OA)] affect technological characteristics of multiple emulsion. Formulation has been prepared by adding investigated solutions (10%) in water/oil/water (W/O/W) multiple emulsion consisting of different lipophilic phases: olive oil and liquid paraffin, with 0.5% emulsifying agent (complex of sodium polyacrylate and polysorbate 20) under constant stirring with mechanical stirrer at room temperature. The emulsion parameters were evaluated using centrifugation test, freeze–thaw cycle test, microscopical and texture analyses. Rosemary's triterpenic saponins UA and OA showed the highest emulsion stabilizing properties: they decreased CI from 3.26% to 10.23% (p < 0.05). According to obtained interfacial tension data, the effect of...