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1.
Titanium complex greases were prepared by using naphthenic mineral oil and polydimethylsiloxane as the mixed base oil. The effect of polydimethylsiloxane molecular weight and polydimethylsiloxane content in mixed base oil on the physicochemical and tribological properties of titanium complex greases was investigated.As compared to the sole mineral oil-based titanium complex grease, the use of polydimethylsiloxane(H201-350)as a co-base oil increased the dropping point from 310 to 329 °C, decreased the oil separation from 3.7% to 2.3%,reduced the corrosion extent, and obviously improved the tribological properties. When the mixed oil-based titanium complex grease was used as a lubricant, lubricating films of polydimethylsiloxane were probably formed on the surfaces of friction pairs, giving good lubricating property.  相似文献   

2.
Soybean oil, commercial news ink vehicles—consisting of either soy or mineral oil and petroleum resins—and United States Department of Agriculture’s (USDA) 100% modified soy oil-based vehicles were subjected to biodegradation. Soybean oil and each vehicle were inoculated with monocultures and a mixed culture of Aspergillus fumigatus, Penicillium citrinum, and Mucor racemosus. Fermentations were allowed to proceed for 5, 12, and 25 d. Results show that, in 25 d, soy oil was degraded the most, followed by the USDA’s ink vehicles (USDA I–III), Newspaper Association of America’s (NAA) hybrid soy oil-based and commercial mineral oil-based vehicles. Some differences were found in the abilities of the cultures to degrade the different inks. Color did not appear to affect the degradation rate in soy oil, the USDA inks, or the NAA ink but was a factor in the commercial ink. Statistician.  相似文献   

3.
At this research the grease (S0) containing [base lube oil grade 260/290, transformer oil, microcrystalline wax, Polyoxyethylene sorbiton‐mono‐palmitate antioxidant 2,2″methylenebis(4‐methyl‐6‐tertiary‐butyl phenol) anticorrosion] was prepared. To improve its physicochemical & dielectric properties (dielectric constant, dielectric loss, and volume resistivity) and giving it a good electrical insulator property, we add to the wax gel a nonpolar polymer as polyethylene, atactic polypropylene, unplastesized polyvinyl chloride, and plasticized polyvinyl chloride include triisopropyle vinyl phosphate in certain concentration. We conclude that the best insulation properties was achevied by adding atactic polypropyle. © 2010 Wiley Periodicals, Inc. J Appl Polym Sci, 2011  相似文献   

4.
BACKGROUND: In this work, the feasibility of biodegradation and the removal performance of sole and mixed odorous vapors, such as dimethyl disulfide (DMDS), methyl phenyl sulfide (MPS), and ethanethiol (EtSH) in an EtSH‐acclimated biotrickling filter seeded with commercially available B350 microorganisms, were investigated. RESULTS: Removal efficiencies (REs) for DMDS as a sole substrate were evaluated under different inlet concentrations and empty bed residence times (EBRT), 100% RE was achieved at concentration below 0.4 g m?3 at EBRT 110 s. In addition, 100% RE was obtained for binary EtSH and DMDS (3:2) at the same EBRT. According to the Michaelis–Menten type kinetic equation, the maximum removal rates (Vmax) were calculated as 28.7 and 13.9 g m?3 h?1 for DMDS and MPS as sole substrate, respectively, while Vmax was 22.1 and 10.1 g m?3 h?1 for DMDS and MPS in the presence of EtSH and EtSH‐DMDS mixture, respectively. After 5 and 20 days starvation, the re‐acclimation times were only 2 and 8 days, respectively, for the binary system. An EtSH:DMDS:MPS (3:2:1) ternary mixture was removed efficiently by the rebooted system after starvation. CONCLUSION: The proposed system can be applied to cost‐effectively decompose a mixture of volatile organic sulfide compounds at pilot scale. Copyright © 2011 Society of Chemical Industry  相似文献   

5.
Enzymatic methanolysis of refined soybean oil with methanol was investigated using Rhizomucor miehei lipase, Lipozyme RM IM, in n-hexane for reaction times of 30 min. Response surface methodology (RSM) based on three-level, three-factor (variable) face-centered cube design was used for the optimization of methanolysis. The independent variables that affect the methanolysis reaction conducted in n-hexane are temperature (°C), enzyme/oil weight ratio, and oil/methanol molar ratio. A good quadratic model was obtained for the methyl ester production by multiple regression and backward elimination. A linear relationship was observed between the observed and predicted values (R2−0.9635). The effects of temperature and enzyme amount, which affected methyl ester content of the product (response) positively, were significant (P<0.01). The quadratic term of temperature and the interaction term of enzyme amount with temperature affected the response negatively (P<0.01). The interaction term of enzyme amount with substrate mole ratio had a positive effect on the response (P<0.05). Critical conditions for the response at which methyl ester content of the product was 76.9% were determined to be 50°C, 2.37 methanol/oil mole ratio, and 0.09 enzyme/oil weight ratio.  相似文献   

6.
生物相容性钛基复合润滑脂的制备   总被引:1,自引:0,他引:1  
钛基复合润滑脂作为综合性能优良的润滑脂,由于良好的发展前景,近年来得到广泛地关注.本文采用植物油作为基础油,通过改变脂肪酸的种类和反应组分配比制备了一系列不同的润滑脂,在12-羟基硬脂酸、钛酸四异丙脂的质量百分比为70∶15∶10∶10的反应条件下,在160℃高温炼制6h制备了性能优良的生物相容性钛基复合润滑脂.  相似文献   

7.
Waste mixed seashells of Perna viridis, Anadara granosa, Amusium pleuronectes, and Meretrix meretrix, as abundant, low-cost, and nontoxic calcium sources, were used as renewable raw materials in the preparation of a heterogeneous base catalyst for the transesterification of palm oil in refluxed methanol. The new mixed metal compound catalyst was prepared by mixing the calcined seashells with Zn(NO3)2 and Al2O3 in an acidic aqueous solution, followed by calcination at 500°C (ZSA-500). The ZSA-500 catalyst exhibited an enhanced surface area, dispersion, and total basicity compared to the parent calcined seashells. The fatty acid methyl ester (FAME) yield attained over ZSA-500 was 99 wt.% and dropped by 3% after five repetitive uses when the reaction was performed for 3 h at 60°C and ambient pressure with 10 wt.% catalyst and a methanol:oil molar ratio of 30:1. Structural and thermal analysis indicated that the active phases of ZSA-500 had a high stability against the glycerol adsorption as well as the phase transformation to calcium glyceroxides (Ca(C3H7O3)2).  相似文献   

8.
Poly(1-octadecene-co-maleic anhydride) bis behanate ester, poly(1-octadecene-co-maleic anhydride) bis stearate ester, and ethylene glycol bis stearate ester were prepared and their structures were confirmed by IR spectroscopy. Wax gel was prepared from base oil blend (base lube oil grade 260/290, transformer oil) and microcrystalline wax in ratio 2.3 : 1, respectively, in the presence of antioxidant and anticorrosion additives in ratio of 0.1–2%. Atactic polypropylene was added in mixture with the above copolymers and ester to the wax gel in different proportions. Dielectric constant, dielectric loss, and volume resistivity at frequency range of 1–103 kHz 35°C have shown better results than that of wax gel alone. The grease which includes poly(1-octadecene-co-maleic anhydride) bis behanate ester in mixture with atactic polypropylene recorded the best results. © 2012 Wiley Periodicals, Inc. J Appl Polym Sci, 2012  相似文献   

9.
This study describes the synthesis, characterization, and thermal behavior of copolymers of methyl methacrylate (MMA) and Np‐tolyl itaconimide (PTI)/N‐phenyl itaconimide (I). Homopolymerization and copolymerization of N‐(phenyl/p‐tolyl) itaconimide with MMA was carried out by use of various mole fractions of N‐aryl itaconimide in the initial feed from 0.1 to 0.5, using azobisisobutyronitrile as an initiator and tetrahydrofuran as the solvent. The copolymer composition was determined by 1H‐NMR spectroscopy using the proton resonance signals attributed to –OCH3 of MMA (δ = 3.5–3.8 ppm) and the aromatic protons (δ = 7.0–7.5 ppm) of N‐aryl itaconimide. The reactivity ratios of the monomers were found to be r1 (PTI) = 1.33 ± 0.05/r2 (MMA) = 0.24 ± 0.03 and r1 (I) = 1.465 ± 0.035/r2 (MMA) = 0.385 ± 0.005. The molecular weight of the copolymers decreased with increasing mole fraction of N‐aryl itaconimide in the copolymers. Glass‐transition temperature (Tg) and thermal stability of PMMA increased with increasing amounts of itaconimides in the polymer backbone. A significant increase in the percentage char yield at 700°C was observed on incorporation of a low mole fraction of N‐aryl itaconimides. © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 89: 1195–1202, 2003  相似文献   

10.
Dilute solution of a styrene-hydrogenated butadiene copolymer, a viscosity index improver, were studied by static and dynamic light-scattering techniques. In n-hexane (a model solvent for paraffinic oils) and a mineral base oil, aggregation is observed below 30°C. In cyclohexane (a model solvent for napthenic oils) only isolated polymers are present in the whole temperature range. Kinematic viscometric measurements from 20 to 60°C in the mineral oil show a continuous increase of the intrinsic viscosity together with a decrease of kH, the Huggins coefficient, from 2.5 to 0.5. At shear rates between 5000 and 40000s?1, a large shear thinning is observed at room temperature for the polymer in the mineral base oil. This effect progressively disappears as the temperature increases and the suspension becomes Newtonian near 100°C. All results can be interpreted in terms of micelle formation. © 1994 John Wiley & Sons, Inc.  相似文献   

11.
Methyl esters (biodiesel) were produced by the transesterification of cottonseed oil with methanol in the presence of solid acids as heterogeneous catalysts. The solid acids were prepared by mounting H2SO4 on TiO2 · nH2O and Zr(OH)4, respectively, followed by calcining at 823K. TiO2-SO4 2− and ZrO2-SO4 2− showed high activity for the transesterification. The yield of methyl esters was over 90% under the conditions of 230°C, methanol/oil mole ratio of 12:1, reaction time 8 h and catalyst amount (catalyst/oil) of 2% (w). The solid acid catalysts showed more better adaptability than solid base catalysts when the oil has high acidity. IR spectral analysis of absorbed pyridine on the samples showed that there were Lewis and Br?nsted acid sites on the catalysts. Translated from The Chinese Journal of Process Engineering, 2006, 6(4): 571–575 [译自: 过程工程学报]  相似文献   

12.
Rates of sodium bisulfite-initiated polymerization of methyl methacrylate in water were determined in absence and in presence of the metal oxides TiO2 and Cu2O at 30°, 40°, 50°, and 60°C. Cuprous oxide and titanium dioxide enhanced the rate of polymerization and reduced the molecular weight as compared with the figures obtained in absence of oxide, the effect of the former being more pronounced than the latter. With TiO2, the rate was increased from 2.3 to 3.2 × 10?5, while with Cu2O, it was increased to 8.6 × 10?5 mole/l./sec, both at concentrations of 9 g/l. water. The apparent energy of activation for the polymerization of methyl methacrylate between 40°C and 50°C was found to be 15.6 kcal/mole in absence of the metal oxides, and 7.6 kcal/mole and 2.8 kcal/mole in presence of titanium dioxide and cuprous oxide, respectively. The number-average molecular weight was found to decrease slightly with the addition of TiO2 but to decrease greatly when Cu2O was added.  相似文献   

13.
Potential applications for colorants derived from the spalting fungi Chlorociboria aeruginascens, Chlorociboria aeruginosa, Scytalidium cuboideum, and Scytalidium ganodermophthorum are of growing interest across a variety of fields, from wood and textile dyes, to solar cells. Previous research found that these dyes could be carried in natural oils, specifically raw linseed oil, instead of organic solvents, thereby eliminating the toxicity issues surrounding such carriers. In this work, dyes from the aforementioned fungi were extracted, carried in raw linseed oil, and mixed with a range of oil and acrylic paints to determine if the oil carrier was appropriate for delivering the dyes into a paint matrix. The oil-based dyes did not mix evenly with the acrylic paints; however, the acrylic paints maintained the color of the dyes. In contrast, the oil-based paints mixed well with the dyes, but the dyes decolorized (completely lost color) due to the presence of refined linseed oil in the paint base. Artists’ paints do not appear to be compatible with fungal dyes when carried in oil; however, there are still many potential applications for the oil-based dyes, such as wood and textile dyeing.  相似文献   

14.
Binary copolymerization of 4‐methyl‐1,3‐pentadiene (4MPD) with styrene, butadiene and isoprene promoted by the titanium complex dichloro{1,4‐dithiabutanediyl‐2,2′‐bis[4,6‐bis(2‐phenyl‐2‐propyl)phenoxy]}titanium activated by methylaluminoxane is reported. All the copolymers are obtained in a wide range of composition and the molecular weight distributions obtained from gel permeation chromatographic analysis of the copolymers are coherent with the materials being copolymeric in nature. The copolymer microstructure was fully elucidated by means of 1H NMR and 13C NMR spectroscopy. Differential scanning calorimetry shows an increase of glass transition temperature (Tg) with the amount of 4MPD in the copolymers with butadiene and isoprene, while in the copolymers with styrene Tg is increased on increasing the amount of styrene. © 2016 Society of Chemical Industry  相似文献   

15.
In this study, poly(dimethyl siloxane) (PDMS)/poly(vinylidene fluoride) (PVDF), poly(phenyl methyl siloxane) (PPMS)/PVDF, poly(ethoxy methyl siloxane) (PEOMS)/PVDF, and poly(trifluropropyl methyl siloxane) (PTFMS)/PVDF composite membranes were prepared. The different functional compositions of these membranes were characterized by Fourier transform infrared spectroscopy. The surfaces and sections of these membranes were investigated by scanning electron microscopy. The hydrophobicity at the membrane surface was assessed with contact angle measurement. Swelling experiments were carried out to investigate the swelling behavior of these membranes. The composite membranes prepared in this study were used in the pervaporation separation of ethanol/water mixtures, and their separation performances were compared. The results show that the separation performances of these membranes were strongly related to the silicone rubber components and composition, the total fluxes decreased in the following order: PDMS > PPMS > PEOMS > PTFMS. The separation factor followed the following order: PPMS > PEOMS > PDMS > PTFMS (5 wt % ethanol at 40°C). In addition, the effects of the feed temperature (40–70°C) and feed composition (5–20 wt %) on the separation efficiency were investigated experimentally. © 2010 Wiley Periodicals, Inc. J Appl Polym Sci, 2011  相似文献   

16.
Abstract

Para‐substituted 4‐aroyl derivatives of 1‐phenyl‐3‐methyl‐5‐pyrazolones (HX), namely, 1‐phenyl‐3‐methyl‐4‐(4‐fluorobenzoyl)‐5‐pyrazolone (HPMFBP) and 1‐phenyl‐3‐methyl‐4‐(4‐toluoyl)‐5‐pyrazolone (HPMTP) were synthesized and examined with regard to the extraction behavior of multivalent metal ions such as magnesium(II), aluminum(III), titanium(IV), vanadium(V), chromium(III), manganese(II), iron(II), and iron(III) that are present in titania waste chloride liquors. For comparison, studies have also been carried out with 1‐phenyl‐3‐methyl‐4‐benzoyl‐5‐pyrazolone (HPMBP). The results demonstrate that vanadium(V) and iron(III) are extracted into chloroform with 4‐aroyl‐5‐pyrazolones as VO2X · HX and FeX3, respectively. On the other hand, magnesium(II), aluminum(III), titanium(IV), chromium(III), manganese(II), and iron(II) were not found to be extracted into the organic phase. The equilibrium constants of vanadium(V) and iron(III) with various 4‐aroyl‐5‐pyrazolones follow the order HPMFBP>HPMBP>HPMTP, which is in accordance with their pKa values. The selectivity between vanadium(V) and iron(III) increases with increasing hydrochloric acid concentration. Further, it is clear from the results that iron(III) is not getting extracted above 1.0 mol dm?3 hydrochloric acid solution. The electronic and IR spectra of the extracted complexes of vanadium(V) and iron(III) were used to further clarify the nature of the extracted complexes. The potential of these reagents for the selective extraction and separation of vanadium(V) from titania waste chloride liquors has also been discussed.  相似文献   

17.
In this study, polymethacrylate polymers were synthesized by free‐radical polymerization for use as pour point depressants in lubricant oil, and their low‐temperature properties were investigated. Four methacrylate monomers were synthesized by the esterification of methyl methacrylate (MMA) with four kinds of fatty alcohols. The purification step was performed to prepare the pure monomers. Two polymerization experiments were carried out with four kinds of methacrylate monomers obtained previously and MMA. Copolymers, which were made from one kind of monomer and MMA, and terpolymers, which were made from two kinds of monomers and MMA, were prepared. The molecular structures of the synthesized methacrylate monomers and polymethacrylate polymers were verified by 1H‐NMR, and the molecular weight data were obtained by gel permeation chromatography. The pour points of the base oils containing 0.1 wt % polymethacrylate polymers were measured according to ASTM D 97‐93. The pour points of most base oils containing each polymer decreased compared to that of the pure base oil. Particularly, poly(dodecyl methacrylate‐co‐hexadecyl methacrylate‐co‐methyl methacrylate), made of dodecyl methacrylate, hexadecyl methacrylate, and MMA at a molar ratio of 3.5 : 3.5 : 3, showed the best low‐temperature properties. This terpolymer dropped the pour point of the base oil by as much as 23°C, and its yield was 93.5%. © 2010 Wiley Periodicals, Inc. J Appl Polym Sci, 2011  相似文献   

18.
In recent studies, the life span of stroke-prone spontaneously hypertensive (SHRSP) rats was altered by a variety of dietary fats. It was relatively shorter in rats fed canola oil as the sole source of fat. The present study was performed to find out whether the fatty acid profile and the high content of sulfur compounds in canola oil could modulate the life span of SHRSP rats. SHRSP rats (47 d old, n=23/group) were matched by body weight and systolic blood pressure and fed semipurified diets containing 10% canola oil, high-palmitic canola oil, low-sulfur canola oil, soybean oil, high-oleic safflower oil, a fat blend that mimicked the fatty acid composition of canola oil, or a fat blend high in saturated fatty acids. A 1% sodium chloride solution was used as drinking water to induce hypertension. After consuming the diets for 37 d, five rats from each dietary group were killed for collection of blood and tissue samples for biochemical analysis. The 18 remaining animals from each group were used for determining their life span. The mean survival time of SHRSP rats fed canola oil (87.4±4.0 d) was not significantly different (P>0.05) from those fed low-sulfur canola oil (89.7±8.5 d), suggesting that content of sulfur in canola oil has no effect on the life span of SHRSP rats. The SHRSP rats fed the noncanola oil-based diets lived longer (mean survival time difference was 6–13 d, P<0.05) than those fed canola and low-sulfur canola oils. No marked differences in the survival times were observed among the noncanola oil-based groups. The fatty acid composition of the dietary oils and of red blood cells and liver of SHRSP rats killed after 37 d of treatment showed no relationship with the survival times. These results suggest that the fatty acid profile of vegetable oils plays no important role on the life span of SHRSP rat. However, phytosterols in the dietary oils and in liver and brain were inversely correlated with the mean survival times, indicating that the differential effects of vegetable oils might be ascribed, at least partly, to their different phytosterol contents.  相似文献   

19.
TiCl4 immobilization on different compositions of mixed support of MgCl2 · xEB and poly(methyl acrylate-co-1-octene) (PMO; synthesized through ARGET ATRP) resulted in the formation of solid catalysts having variation in incorporation of titanium. The effect of mixed support composition onto the titanium immobilization, catalyst morphology and performance for ethylene polymerizations has been evaluated. The polyethylenes synthesized showed broad to bimodal MWD in GPC and DSC where the broadness was found to be dependent upon the ratio of mixed support MgCl2 · xEB/PMO. The morphological features of PE as elucidated using SEM lead to postulation of polymer formation mechanism.  相似文献   

20.
采用合成酯类油邻苯二甲酸二辛酯作为基础油合成复合锂基润滑脂,并对其进行各项性能指标分析,探究其综合性能及应用。制备的润滑脂具有很高的滴点和胶体安定性及较好的低温性能。热重分析表明将邻苯二甲酸二辛酯制备成脂后,其热稳定性有所提高.低温DSC表明成脂后,其结晶温度与酯油相同,仍然保持较好的低温性能。扫描电镜结果表明润滑脂形成致密的皂纤维结构。  相似文献   

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