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81.
ABSTRACT: This study measures the electric conductance and examines the microscopic structure of bamboo shoots, sugarcane, lettuce stem, and mustard stem. The electric conductance readings vary from 0.09 S/m to 0.72 S/m across the stem, and from 0.19 S/m to 0.46 S/m along the stem. The electric conductance along the stem is higher than the electric conductance across the stem in bamboo shoots and sugarcane, while the reverse is true in lettuce stem and mustard stem. The orientation of vascular bundles and the shape of parenchyma cells are proposed to account for the different conductance readings from the same vegetable in different directions. The orientation of vascular bundles appear to influence electric conductance more than the shape of parenchyma cells when both factors are present in the same time. 相似文献
82.
Many short-run studies point to the potential for direct fueling of compression ignition engines with plant oil fuels. There is a much smaller body of work that examines the potential for these fuels in long-run tests that illuminate engine endurance and longevity issues. Generally, longevity studies involving direct fueling of engines with straight plant oils have shown significant impact to the life of the engine, though test results vary widely depending on the oil, engine type, test conditions, and measurement approach. This study utilizes a previously designed modification kit [1] to investigate the longevity implications of directly fueling straight plant oil in an indirect injection (IDI) listeroid type, slow speed stationary engine common in agro-processing applications in developing countries. Specifically this study focuses on the lubrication oil by developing a model to characterize the engine wear and estimate lube oil change frequency. The model is extended to an analysis of the piston rings. Cylinder liner wear, emissions, engine performance, and a visual investigation of several critical engine components are also studied. 相似文献
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84.
López Antonio Montaño Alfredo Garrido Antonio 《Journal of the American Oil Chemists' Society》2005,82(2):129-133
A survey of vitamin E levels in a wide variety of olive-based foodstuffs was conducted. Vitamin E was determined by normal-phase
HPLC. The only form of vitamin E found in all commercial presentations of table olives was α-tocopherol, with an average content
of 3.1 mg/100 g edible portion. A very low content (<0.4 mg/100 g edible portion) of γ-tocopherol was found in most of the
samples analyzed. The main sources of variation of vitamin E were olive cultivars and commercial presentations. Processing
type (Spanish style green olives, directly brined olives, ripe olives) had a limited influence. Irrespective of the elaboration
style, the Gordal cultivar was the poorest with respect to the vitamin E content. On the other hand, all commercial presentations
based on the Hojiblanca cultivar had high contents of vitamin E. The results of this study may be used by the industry for
requirements of nutritional labeling or by nutritionists to estimate vitamin E intakes in diets that include table olives. 相似文献
85.
Alternate oils in fish feeds 总被引:1,自引:0,他引:1
Nearly half of the fish consumed as food worldwide are raised on fish farms rather than caught in the wild, as shown by FAO statistics. The increasing aquaculture of predatory carnivorous fish demands new sources of feed constituents, particularly oils at the moment. Common terrestrial plant oils contain only traces of the long‐chain polyunsaturated fatty acids. In connection with fish feed, especially the lack of n‐3 “marine fatty acids” is obvious. Recommendations on the required amounts of the fatty acids DHA (22:6n‐3) and EPA (20:5n‐3) exist from 1994. When plant oil‐based diets are fed during the growing phase and replaced by a fish oil‐based diet during a period prior to slaughter, most of the beneficial lipid composition of fish in terms of human dietary recommendations is restored. Little attention has been focused on the fish welfare in connection to substitution of dietary oil sources, and studies are still scarce. New fish diets will rely heavily on the use of alternate ingredients such as plant oils also for carnivorous cold‐temperate water fish species. In the future, an addition of synthetic or GMO‐produced “marine” fatty acids is a possible scenario. The aim of this review is to highlight some plant oils used in fish feeds, with special emphasis on compounds other than fatty acids. We also include some results from an ongoing study, where the effect of dietary soy oil on gonad maturation in Atlantic cod (Gadus morhua) is indicated. 相似文献
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87.
为了探究不同油浸变压器受火情况下的火灾动力学过程,搭建了全尺度变压器火灾实验平台,分别针对基于RAPO天然酯植物油和25号变压器油的10 kV油浸变压器开展了外部热源耐火实验。研究结果表明,在同一外部热源条件下,矿物油变压器在受火状态下9 min左右即出现猛烈的喷射火灾现象,喷射出的矿物油品同时导致了大面积的池火和流淌火灾,使得火灾进一步加剧。相比而言,植物油变压器燃烧相对平缓,在24 min左右才出现轻微的喷射火现象,但并未造成明显的火灾加剧,且实验结束后变压器周边残存大量未燃植物油。在燃烧实验中,植物油的温升速率约为0.18 ℃/s,显著低于矿物油的0.24 ℃/s,也进一步说明了植物绝缘油的安全性。从消防安全角度,植物油变压器的火灾安全性远胜于矿物油变压器,具有较好的应用前景。 相似文献
88.
89.
综述了蔬菜生产基地选择所考虑的综合因素、资质和能力、基地的自然条件要求、基地的规模与布局要求、设施设备条件要求、基地人员要求等,并就基地的土壤和基质、灌溉、施肥和肥料、农药的使用、收获、包装和标识、文件与记录、追溯与召回等方面提出管理要求,供蔬菜生产基地的选择和管理参考使用。 相似文献
90.