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Biswas A Sharma BK Willett JL Advaryu A Erhan SZ Cheng HN 《Journal of agricultural and food chemistry》2008,56(14):5611-5616
An environmentally friendly water-based pathway to form the azide derivatives of soybean oil and fatty esters is reported. This entails first the formation of epoxides and then the azidization of the epoxides. The azidization reaction is carried out at high yields in water with only a small amount of an ionic liquid as a catalyst. The distribution of azide and alcohol functionalities on the fatty acid moiety is approximately random. This reaction has been applied to methyl oleate, methyl linoleate, soybean oil, and methyl soyate. The resulting structures have been studied by NMR. 相似文献
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A. Singh Brajendra A. Nath B.C. Deka 《The Journal of Horticultural Science and Biotechnology》2013,88(6):551-555
SummaryStrawberry (Fragaria ananassa Duch.) is a rich source of minerals, vitamins, and anti-oxidants, and has a unique flavour and aroma. However, there is little information on the genetic variability and inheritance of mineral elements in strawberry. This is important as it can influence the selection of better genotypes and suitable breeding approaches for improvements in the nutritional quality of fruit. The objectives of the present study were, therefore, to estimate the variability, inheritance, and inter-relationships of mineral elements, to identify mineral-rich and productive genotypes, and to suggest suitable breeding approaches. A significant genotypic mean square for all the minerals studied indicated sufficient variation among genotypes. Our results also indicated that the effect of genotype on the mineral content of fruit was stronger than that of environment. Six genotypes, namely ‘Ofra’, ‘Sweet Charlie’, ‘Elista’, ‘Festival’, ‘Camarosa’, and ‘Douglas’ were found to have higher mineral contents as well as better fruit yields, and therefore could be useful in further breeding programmes. N, K, Ca, Mg, Fe, Mn, Zn, and Cu contents, together with fruit yield, could be improved by selection and hybridisation as these traits showed high heritability (> 80%) and high genetic advance as a percentage of the mean (> 40%), while recurrent selection was suitable for increasing P contents, which showed moderate heritability (> 79.81%) and low genetic advance as a percentage of the mean (> 33.86%). Moreover, Mg and N contents could be used as reliable tools with which to identify the most productive and mineral-rich genotypes, as indicated by correlation and path analysis. Studies on such genetic estimates will increase our understanding of the inheritance of mineral contents and affect the design of crop improvement strategies. 相似文献
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Erhan SZ Sharma BK Liu Z Adhvaryu A 《Journal of agricultural and food chemistry》2008,56(19):8919-8925
The environment must be protected against pollution caused by lubricants based on petroleum oils. The pollution problem is so severe that approximately 50% of all lubricants sold worldwide end up in the environment via volatility, spills, or total loss applications. This threat to the environment can be avoided by either preventing undesirable losses, reclaiming and recycling mineral oil lubricants, or using environmentally friendly lubricants. Vegetable oils are recognized as rapidly biodegradable and are thus promising candidates as base fluids in environment friendly lubricants. Lubricants based on vegetable oils display excellent tribological properties, high viscosity indices, and flash points. To compete with mineral-oil-based lubricants, some of their inherent disadvantages, such as poor oxidation and low-temperature stability, must be corrected. One way to address these problems is chemical modification of vegetable oils at the sites of unsaturation. After a one-step chemical modification, the chemically modified soybean oil derivatives were studied for thermo-oxidative stability using pressurized differential scanning calorimetry and a thin-film micro-oxidation test, low-temperature fluid properties using pour-point measurements, and friction-wear properties using four-ball and ball-on-disk configurations. The lubricants formulated with chemically modified soybean oil derivatives exhibit superior low-temperature flow properties, improved thermo-oxidative stability, and better friction and wear properties. The chemically modified soybean oil derivatives having diester substitution at the sites of unsaturation have potential in the formulation of industrial lubricants. 相似文献
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Sharma BK Adhvaryu A Perez JM Erhan SZ 《Journal of agricultural and food chemistry》2005,53(8):2961-2968
The biodegradable properties and lubricating ability of greases depend on both the base oil and the thickener. Mineral oils are the most widely used lubricant base fluids due to their inherent lubricity and low cost, but recent environmental awareness has forced consideration of the use of biodegradable fluids such as vegetable oils and certain synthetic fluids in grease formulations. This study presents data on the thermo-oxidation behavior and tribology of biodegradable greases formulated with soybean oil and different compositions of metal soap thickener. The composition of thickener has been varied by using fatty acids with different degrees of unsaturation and fatty acids of different chain lengths. The improvement of thermo-oxidation and tribological properties as a result of changing thickener/base oil ratio and the antioxidative effect of some suitable additives have also been evaluated. 相似文献
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Sharma BK Adhvaryu A Perez JM Erhan SZ 《Journal of agricultural and food chemistry》2006,54(20):7594-7599
Vegetable oils have significant potential as a base fluid and a substitute for mineral oil for grease formulation. This paper describes the preparation of biobased grease with high oxidative stability and a composition useful for industrial, agriculture/farming equipment, and forestry applications. The process utilizes more oxidatively stable epoxy vegetable oils as the base fluid, metal-soap thickener, and several specialty chemicals identified to address specific applications. Performance characteristics of greases used for industrial and automotive applications are largely dependent on the hardness and the oxidative stability of grease. Grease hardness was determined using standard test methods, and their oxidative stabilities were determined using pressurized differential scanning calorimetry and rotary bomb oxidation tests. Wear data were generated using standard test methods in a four-ball test geometry. Results indicate that grease developed with this method can deliver at par or better performance properties (effective lubrication, wear protection, corrosion resistance, friction reduction, heat removal, etc.) than existing mineral oil-based greases currently used in similar trades. Therefore, developed greases can be a good substitute for mineral oil-based greases in industrial, agriculture, forestry, and marine applications. 相似文献
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Bio-based additives are desirable commodities due to their eco-friendly nature. These additives can demonstrate physical and chemical properties comparable to those of conventional mineral oil-based products. Sulfur incorporated triacylglycerol can function as an antiwear/antifriction additive for lubricants. The synthesis of four useful hydroxy thio-ether derivatives of vegetable oils, from commercially available epoxidized soybean oil and common organic thiols, is reported in this paper. The common thiols used herein were 1-butanethiol, 1-decanethiol, 1-octadecanethiol, and cyclohexyl mercaptan. Currently, there is no reported literature describing the synthesis of hydroxy thio-ether derivatives of vegetable oil. The reaction was monitored, and products were confirmed by NMR and FTIR spectroscopies. Experimental conditions involving various thiols, solvent, catalyst amount, time, and temperature were optimized for research quantity and laboratory scale-up. The synthetic process retains the vegetable oil structure, eliminates polyunsaturation in the molecule, and adds polar functional groups on triacylglycerol. These products can be used as agriculturally-based antiwear additives for lubricant applications. 相似文献
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A. Kumaresan K. M. Bujarbaruah K. A. Pathak Brajendra T. Ramesh 《Tropical animal health and production》2010,42(4):569-577
The purpose of the present study was to study the soil–plant–animal continuum in subtropical hilly areas. Soil (n?=?96), fodder (n?=?96), and blood serum samples from dairy cattle (n?=?120) were collected from eight districts of Mizoram, a hilly state in India. The samples were digested using diacid mixture (HNO3:HClO4; 10:4) and analyzed for macro (Ca, P, Mg, Na, and K) and micro (Cu, Co, Mn, Fe, and Zn) mineral concentrations. The macro and micro mineral concentrations varied among the different districts. The correlation values between fodder and cattle were significant for all the minerals studied except for P and K. The correlation value between fodder and cattle was highly significant (P?<?0.01) for Ca (0.878), Mg (0.88), Cu (0.885), and Zn (0.928). However, such correlations were not observed between the mineral levels in cattle and mineral levels in soil except for Ca (0.782). Equations developed in the present study for prediction of Ca (R 2?=?0.797), Mg (R 2?=?0.777), Zn (R 2?=?0.937), Fe (R 2?=?0.861), and Cu (R 2?=?0.794) had significant R 2 values. Further, it is inferred that dairy cattle reared under smallholder production system were deficient in most of the minerals and supplementation of required minerals is essential for optimum production. 相似文献
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Biswas A Sharma BK Vermillion K Willett JL Cheng HN 《Journal of agricultural and food chemistry》2011,59(7):3066-3070
This paper describes the preparation of a new type of branched vegetable oil and its methyl ester that involves the formation of acetonides. A facile and environmentally friendly synthesis has been found to produce acetonides that entails the use of ferric chloride as a catalyst and is conducted at room temperature. The products have been fully characterized with the help of model compounds, including elemental analysis, infrared (IR) spectroscopy, nuclear magnetic resonance (NMR), and gas chromatography-mass spectrometry (GC-MS). 相似文献
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Sharma BK Liu Z Adhvaryu A Erhan SZ 《Journal of agricultural and food chemistry》2008,56(9):3049-3056
Vegetable oils are promising candidates as substitutes for petroleum base oils in lubricant applications, such as total loss lubrication, military applications, and outdoor activities. Although vegetable oils have some advantages, they also have poor oxidation and low temperature stability. One of the ways to address these issues is chemical modification of fatty acid chain of triglyceride. We report a one-pot synthesis of a novel class of chemically modified vegetable oils from epoxidized triacylglycerols and various anhydrides. In an anhydrous solvent, boron trifluoride etherate is used as catalyst to simultaneously open the oxirane ring and activate the anhydride. The reaction was monitored and products confirmed by NMR, FTIR, GPC, and TGA analysis. Experimental conditions were optimized for research quantity and laboratory scale-up (up to 4 lbs). The resultant acyl derivatives of vegetable oil, having diester substitution at the sites of unsaturation, have potential in formulation of industrial fluids such as hydraulic fluids, lubricants, and metal working fluids. 相似文献
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