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1.
Compared to the lubricants made of petroleum, vegetable-based lubricants are much more biodegradable but inferior in many other technical characteristics. The basestock typically contributes to more than 80% of lubricant and must meet performance criteria in such aspects as cleanliness, viscometric properties, volatility, oxidative and hydrolytic stability, deposit forming tendencies, solvency, miscibility or compatibility with system elastomers and other. For vegetable-based lubricants, oxidative stability and low temperature problems are considered the most critical. Thin film oxidation test was used to compare oxidative stabilities. Vegetable oils appear an order of magnitude less stable than mineral oils or synthetic biodegradable basestocks, such as isoalkyl adipates or poly alphaolefins. Low temperature performance of vegetable oils, namely pour points and cold storage, was also problematic. These problems can only partially be relieved by lubricant additives, thus vegetable oils have to be modified chemically to eliminate sites susceptible to oxidation and to disrupt formation of crystals at low temperatures.  相似文献   

2.
As important supplementary to major edible oils, comparative chemical advantages of minor edible oils decide their development and usage. In this study, chemical composition of 13 kinds of specific edible vegetable oils were investigated. The comparative advantages of chemical compositions of these edible oils were obtained as follows: (1) camellia, tiger nut and almond oil were rich in oleic acid, the contents of which accounted for 79.43%, 69.16% and 66.26%, respectively; (2) safflower oil contained the highest content of linoleic acid (76.69%), followed by grape seed (66.85%) and walnut oil (57.30%); (3) perilla seed, siritch, peony seed and herbaceous peony seed oil were rich in α-linolenic acid (59.61%, 43.74%, 40.83% and 30.84%, respectively); (4) the total phytosterol contents of these oils ranged from 91.46 mg/100 ​g (camellia oil) to 506.46 mg/100 ​g (siritch oil); and (5) The best source of tocopherols was sacha inchi oil (122.74 mg/100 ​g), followed by perilla seed oil (55.89 mg/100 ​g), peony seed oil (53.73 mg/100 ​g) and herbaceous peony seed oil (47.17 mg/100 ​g). The comparative advantages of these specific edible oils indicated that they possess the high potential nutritional values and health care functions.  相似文献   

3.
In this paper, it was aimed to obtain disposable medical textiles having antibacterial and wound healing properties, as well as biological adaption. For this purpose, the St. John’s Wort oil and flax seed oil were ozonated, and the oils were capsulated with arabic gum. The produced ozonated oils were characterized through FTIR and TGA analyses, as well as the properties of antibacterial, wound healing, and biological adaption were investigated. The produced microcapsules were examined via optical microscope and FTIR. The characterized microcapsules of the ozonated oils were applied to the textiles with padding method. After the applications, the fabrics were researched with SEM and FTIR analyses; in addition the antibacterial and wound healing properties and biological adaption of the textiles were also investigated. The results showed that the St. John’s Wort oil and flax seed oil were successfully ozonated and microcapsulated. The microcapsules of the oils could be applied to the fabric samples with the determined application recipe. The ozonated oils and the fabric samples applied microcapsules of the ozonated oils gained high antibacterial and wound healing property. In addition, the fabric samples were produced as having biological adaptation.  相似文献   

4.
Multiple novel vegetable oil-based polyols were synthesized from the reaction-addition to epoxidized soybean oil (ESBO) by a series of acid acyl moieties derived from vegetable oils. The acid acyl moieties were linoleic acid (LA), ricinoleic acid (RC), ricinoleic acid estolide (RC estolide) and hydrolyzed bodied soybean oil (HBSBO). LA and RC were commercially available but RC estolide and HBSBO were synthesized by enzymatic catalytic reactions. In the reaction-addition, ESBO was heated with the acid acyl moieties at 170 °C, atmospheric pressure without any catalyst and solvent. The synthesized vegetable oil-based polyols had acid numbers less than 10 (mg KOH/g), hydroxy numbers of 82–152 (mg KOH/g), and hydroxyl equivalent weights of 370–680. The polyols made from RC estolide and HBSBO had improved numbers of OH equivalent weight comparing to the numbers from alkoxyl hydroxyl soybean oil which is widely used commercial soy-based polyols.  相似文献   

5.
The oxidative stability indices (OSI) of several vegetable oils were determined at 110°C. Meadowfoam oil, Limnanthes alba, was found to be the most stable oil with an OSI time of 67.3 h for refined oil and 246.9 h for crude oil. Other oils with good oxidative stabilities were refined high oleic sunflower and crude jojoba oil (Simmondsia chinensis) with OSI times of 49.8 and 34.5 h respectively. The unusually high OSI time of crude meadowfoam oil could not be attributed to its tocopherol content since refining did not significantly alter the tocopherol content, but significantly reduced the stability. A relationship of iodine value to antioxidant was developed for vegetable oils; however, this linear relationship did not account for the unusually high oxidative stability of meadowfoam oil. Binary mixtures of vegetable oils were also examined for enhanced oxidative stability. Small amounts of crude meadowfoam oil gave enhanced oxidative stability in mixtures with jojoba, triolein and castor oils. Triolein/crude meadowfoam oil mixtures showed the most dramatic improvements in OSI time with a 5% (w/w) addition of crude meadowfoam causing a 21-fold increase in the OSI time. Meadowfoam mixtures with jojoba improved the OSI time of jojoba from 31.1 to 52.7 h, when 10% crude meadowfoam oil was added. A study of oxidative stability with respect to olefin position showed that the Δ5 double bond was the most stable by more than an order of magnitude. The oxidative stability of meadowfoam FAMEs at 90°C gave an OSI time of 4.9 h which was the same as methyl erucate and methyl petroselenate, but less than methyl oleate which had an OSI time of 14.8 h. However, when methyl 5-eicosenoate was isolated in high purity (monoene >96%) and tested, it gave an OSI time of 69.4 h.  相似文献   

6.
Epoxidised Jatropha seed, Khaya seed and rubber seed oils were prepared at 29 °C by using peracetic acid generated in situ by reacting glacial acetic acid and hydrogen peroxide. The barium, cadmium and lead soaps of the epoxidised oils are prepared by metathesis in aqueous alcohol solution. The effects of the epoxidised vegetable oils and their metal soap derivatives on the rate of the thermal degradation of polyvinyl chloride and on the viscosity of the polymer samples degraded at 190 °C were studied. The effectiveness of the additives (epoxidised oils and their metal soaps) in stabilising polyvinyl chloride against thermal degradation was assessed by comparing the kinetic and viscosity data obtained for the degradation of the polymer in the presence of the additives with corresponding values obtained in the absence of the additives. It was found that the additives retard the rate of degradation and reduce the extent of polymer chain scission associated with the thermal degradation of polyvinyl chloride. The metal soaps of the epoxidised oils were found to be generally more effective than the epoxidised oils in stabilising polyvinyl chloride against thermal degradation.  相似文献   

7.
基于主要农艺性状及AFLP分子标记技术,对40份入选菜用大豆品种进行遗传多样性评价,为拓宽菜用大豆种质资源基础及新品种选育提供理论依据。研究结果表明,基于农艺性状及品质性状的聚类将40份材料划分为3个类群;AFLP标记数据聚类将40个材料划分为3个AGs(AFLP-based groups)分子类群,且聚类结果与材料的地理来源无关。另外,8对AFLP引物共扩增出30条多态性条带,平均每对引物3.75个等位变异;品种间的遗传相似系数变化范围为0.3704-0.9998,平均值变化范围为0.5980-0.7924,总体平均值为0.7094,说明供试材料间的遗传相似系数较高,遗传差异较小,因此必须进一步加强菜用大豆种质资源的筛选和创新工作。  相似文献   

8.
花生脂肪酸组分的遗传效应研究   总被引:12,自引:1,他引:12  
采用Griffing列杂交设计模式对花生主要脂肪酸组分进行Hayman遗传分析。结果表明,O/L比值及油酸,亚油酸,棕榈酸,硬脂酸,山嵛酸含量等性状均符合“加性-显性”模型,以加性效应为主并表现部分显性遗传。亲本各性状的显,隐性基因频率,正负效应基因比例,显、隐性基因的方向均不同。O/L比值,油酸,亚油酸,棕榈酸,山嵛酸的遗传力较高,早代即可进行严格选择。鲁花10号和辐8707含有较多控制O/L比值及油酸含量的隐性增效基因,强盗花生和ICG6848含有较多控制亚油酸含量的显性增效基因,因此可作为高O/L比值及高营养品质育种的亲本。  相似文献   

9.
The characterization of the essential oil profile together with the sensory analysis of five samples of oregano, four of which cultivated in different areas of Sicily and one of commercial origin, have been carried out. The Sicilian cultivated samples belong to Origanum vulgare ssp. hirtum (Link) Béguinot (syn. O. heracleoticum L.), the most typical Sicilian oregano species. The essential oils, obtained by hydrodistillation, have been analysed by GC-FID-MS. On the whole, 53 compounds representing more than 98% of the oils have been fully characterized. The four cultivated samples showed a very similar chemical profile, thymol and γ-terpinene being the main compounds followed by p-cymene, α-terpinene, carvacrol and thymol methyl ethers, myrcene and carvacrol. The commercial sample, instead, showed a different profile, with carvacrol largely being the main component (>77%), followed by p-cymene, γ-terpinene and thymol, in that order.According to the chemical composition, the sensory profile of the Sicilian oregano samples proved fairly homogenous, whereas different results were obtained for the commercial sample. Indeed, the intensity of sensory attributes “typical oregano flavour” and off-flavour are similar for the four cultivated samples; instead the commercial sample has less freshness and a lower typical oregano flavour, associated with a higher level of off-flavour.  相似文献   

10.
Five different Glu-B1 HMW-GS patterns were identified among a collection of diverse durum wheat genotypes grown in 2001 in two locations in western Canada. The durum wheat lines exhibited a wide range of dough and gluten strength characteristics as measured by alveograph and 2 g mixograph parameters, gluten index (GI), and protein composition as measured by unextractable polymeric protein (UPP) content and the ratio of high-molecular weight (HMW) glutenin subunits (GS) to low-molecular weight (LMW) GS. HMW-GS subunits patterns represented within the genotypes were 6+8, 7+8, 7+16, 14+15 and 20. Two of the genotypes expressed Glu-A1 HMW-GS 2* in combination with other HMW-GS. Approximately 95% of the durum genotypes were γ-gliadin 45 types. Analysis of variance indicated that genotype was a greater source of variation in all measurements than was growing location, with the exception of protein content which showed less variation contributed by genotype and more contributed by location than for other quality parameters. UPP was strongly associated with all strength measurements. All of the γ-gliadin 42 types were low in UPP and weak. Among the γ-gliadin 45 types, those possessing HMW-GS 20 were typically in the lower half of the UPP and strength range. There was no clear evidence of an association between any of the other HMW-GS patterns and gluten strength. The majority exhibited HMW to LMW-GS ratios that were within the relatively narrow range of 0.15–0.25, yet there were wide variations in dough strength among genotypes within that range. Increasing proportions of HMW-GS resulting in ratios of greater than 0.30 were generally associated with weak dough and gluten and low UPP content.  相似文献   

11.
The genetic variation in the nutrient composition and anti-nutritional factors of 17 vegetable soybean genotypes were determined and a wide variation in protein %, total phosphorus (TPi) and available phosphorus (AP) was found among these genotypes. Variations in Ca, K, Fe, Mn, and Cu were also documented. Variation was also found for trypsin inhibitor (TI) activity and Phytate (PA) content. A highly significant and negative correlation (r=–0.533,P<0.01) was observed between TI and total protein. Strong positive correlation (r=0.90) was also found between TPi and AP. Several genotypes (Sooty, Emperor, Wilson-5, PI 416771, PI 417322) showed good nutritional potential and can be used in the breeding program. High protein %, TPi, and minerals are desirable qualities for vegetable-type soybeans that make it as food with high nutrient density. Studies on the nutritional evaluation of immature vegetable type soybean seeds at different reproductive stages are also underway.Agricultural Research Station Journal Article Series No. 172. The use of any trade name varieties, and/or vendors does not imply the exclusion of other products or vendors that may also be suitable.  相似文献   

12.
A wild crop of athalakkai was identified, and the majornutrients of its fruits were assessed. South Indian recipes, poriyal,fry, pulikulambu, pickle, and vadagam, were prepared using athalakkai.Product acceptabilities were evaluated by a panel of 10 trained housewives using a 9, point hedonic scale. It was observed that athalakkai containshigher amounts of calcium, potassium, sodium and vitamin C than bittergourd (Momordica charantia L). It was also observed that athalakkaihad a high crude fiber (6.42 g/100 g) content. The recipes prepared fromathalakkai were highly acceptable. This research suggests the need to exploitthis wild vegetable commercially through its increased use. Howeverresearch should be conducted to identify the antinutritional factors and theeffect of processing on these factors.  相似文献   

13.
Lignin residues are available in large amounts as kraft lignin from chemical pulping processes. This lignin is mainly incinerated in recovery boilers. The recovery boilers are often the bottle-necks in the overall pulping process when pulp production increases are desired. Through cross-flow nano-filtration of the black liquor from kraft pulping, a low-molecular weight lignin fraction can be removed thus decreasing the organic load on the recovery boilers. The low-molecular weight lignin fraction furthermore exhibit different characteristics compared to other commercial kraft lignins and represents a new raw material source in novel applications.The low-molecular weight lignin was used together with a vegetable oil to produce a new hydrophobic lignin derivative similar to suberin. The lignin and the lignin derivative was analysed with FT-IR, UV–vis and SEC. The ability of the product to make paper surfaces hydrophobic was also evaluated.The results demonstrate the possibility to make a suberin-like lignin derivative that is potentially of interest in paper-coating applications due to its capability to interact well with wood fibres and make paper hydrophobic.  相似文献   

14.
Crude vegetable oil obtained by solvent extraction from rubber seed (Hevea brasiliensis) and breadfruit (Artocarpus altilis) were subjected to alkali refining (neutralisation), degumming and bleaching. At each stage of refining, the crude and the refined oil were analysed for their physical and chemical characteristics notably specific gravity, moisture and volatile matter content, saponification, iodine values, peroxide value, unsaponifiable matter, fatty acids and free fatty acids. Results showed an improvement in the quality of the oil after refining. Refining decreased the free fatty acids and peroxide value, which are some of the characteristics that determine stability. There was a very slight decrease in saponification value and unsaponifiables matter after refining. Refining did not have much effect on the fatty acid composition except slight nonconsistent decreases in saturated and unsaturated fatty acids. There was no decrease in iodine value.  相似文献   

15.
16.
Choice of the shortening ingredient in bread products has functionality effects and health implications. Little information is available on effects of various shortening ingredients on palatability and acceptability. The objective of the current study was to compare the acceptability of yeast-leavened wheat breads containing shortenings containing predominantly saturated fatty acids (coconut oil), monounsaturated fatty acids (canola oil) or unsaturated fatty acids (unhydrogenated soybean oil). Breads were prepared using a standardized formula and method. These were evaluated by a 16-member, semi-trained panel for color, flavor, texture, tenderness and overall acceptability using a seven-point hedonic scale. No significant differences in color and texture were defined; however, canola oil bread was judged significantly superior to soybean oil bread in flavor, and both of these breads were found to be significantly superior to coconut oil bread in flavor, tenderness, and overall acceptability.  相似文献   

17.
Fatty acid analyses of seed lipids were performed for 28 populations representing three widely distributed Cuphea species. Locality and climatic data for all samples were also compiled. The objectives of this study were to examine the extent of variation in seed oil composition among the wild populations, and to discover any patterns of relationship between fatty acid composition of seed oils and environmental factors. While we found the dominant fatty acid in the oil of each species remained consistent over the environmental and geographical ranges of the samples in the present study, variation as high as 30.6% in the amount of the dominant fatty acid produced was observed. Correlation analysis between fatty acid composition and the individual environmental factors of latitude, elevation or temperature showed no consistent pattern of influence. However, when considered together, the interaction of all three, and especially latitude and elevation, contributed significantly to the variation among populations. Environmental data at microhabitat level and through controlled environmental experiments will be needed for more precise understanding of factors affecting Cuphea seed oil composition at the population level.  相似文献   

18.
Grassland systems frequently exhibit small‐scale botanical and structural heterogeneity with pronounced spatio‐temporal dynamics. These features present particular challenges for sensor applications, in addition to limitations posed by the high cost and low spatial resolution of many available remote‐sensing (RS) systems. There has been little commercial application of RS for practical grassland farming. This article considers the developments in sensor performance, data analysis and modelling over recent decades, identifies significant advances in RS for grassland research and practice and reviews the most important sensor types and corresponding findings in research. Beside improvements of single sensor types, the development of systems with complementary sensors is seen as a very promising research area, and one that will help to overcome the limitations of single sensors and provide better information about grassland composition, yield and quality. From an agronomic point of view, thematic maps of farm fields are suggested as the central outcome of RS and data analysis. These maps could represent the relevant grassland features and constitute the basis for various farm management decisions at strategic, tactical and operational levels. The overarching goal will be to generate low cost, appropriate and timely information that can be provided to farmers to support their decision‐making.  相似文献   

19.
The hydrodistilled essential leaves and stems oils of Orthosiphon stamineus Benth were analysed by GC–MS/MS. Sixty nine compounds representing 97.6 and 97.4% of the total leaves and stems oils, respectively were identified, of which β-caryophyllene (24.0 and 35.1%), α-humulene (14.2 and 18.4%), β-elemene (11.1 and 8.5%), 1-octen-3-ol (8.2 and 7.0%), β-bourbonene (3.4 and 3.0%), β-pinene (2.1 and 1.7%), caryophyllene oxide (1.6 and 2.2%), camphene (1.6 and 1.3%) and limonene (1.2 and 1.1%) were the major compounds. Thus, the monoterpenes and sesquiterpenes were the predominant portions of the oils. Essential oils and methanol extract of O. stamineus and the derived fractions of hexane, chloroform, and ethyl acetate were tested for anti-fungal activity, which was determined by disc diffusion and minimum inhibitory concentration (MIC) determination methods. The oils, methanol extract and derived fractions of methanol extract displayed great potential of anti-fungal activity as a mycelial growth inhibitor against the tested phytopathogenic fungi such as Botrytis cinerea, Rhizoctonia solani, Fusarium solani, Colletotricum capsici and Phytophthora capsici, in the range of 49.3–70.3% and minimum inhibitory concentration ranging from 500 to 1000 μg/ml.  相似文献   

20.
The composition and quality of edible tender stems or cladodes of 3 Prickly Pear Cactus species (Opuntia amyclaea, O. ficus-indica, and O. inermis) were studied at different stages of development. This traditional Mexican vegetable is called nopalitos in Spanish and cactus leaves in English. Cladodes harvested when 20 cm in length have the following average composition per 100 g: 91.7 g of water, 1.1 g of protein, 0.2 g of lipid, 1.3 g of ash, 1.1 g of crude fiber, 4.6 g of complex carbohydrates and 0.82 g of simple sugars, 12.7 mg of ascorbic acid and 28.9 µg of carotenes. The cladode's juice has an average pH of 4.6, 0.45% titratable acidity and 6.9% soluble solids. The components which varied most during development of the cladodes were: carotenes, acidity and total carbohydrates which increased, and protein and crude fiber (acid-detergent) which decreased. The nutritive value of the tender cladodes in the stages of growth at which they are commonly harvested and consumed (15 to 25 cm long weighing 50 to 80 g per stem), was similar for the 3 species.  相似文献   

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