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61.
板锥网壳结构是一种受力性能合理 ,技术经济效益良好的新型空间结构形式。对板锥网壳结构的自振特性及其影响因素进行了系统分析研究 ,并与普通双层网壳结构进行比较 ,得出了可应用于工程实践的重要结论 相似文献
62.
Herein, we report an efficient process for preparing monodisperse Au@SiO2 nanoparticles using homogeneous shaking and without the use of surface‐coupling silane agents or large stabilizers. The resulting pure‐silica surface of the Au@SiO2 nanoparticles is very important for straightforward surface functionalization with different functional groups via well‐established silica surface chemistry. Subsequent covalent bioconjugation of the aldehyde‐functionalized Au@SiO2 nanoparticles with various biomolecules is successfully employed to make robust nanoprobes for fast, colorimetric DNA and protein detection based on the sequence‐specific hybridization properties of DNA and the specific binding affinity between proteins, respectively. 相似文献
63.
Stavros Lalas John Tsaknis Konstantinos Sflomos 《European Journal of Lipid Science and Technology》2003,105(1):23-31
The oil from Moringa stenopetala seeds variety Marigat from the island Kokwa was extracted using 3 different procedures including cold press (CP), extraction with n‐hexane and extraction with a mixture of chloroform:methanol (1:1) (CM). The yield of oil was 35.7% (CP) to 44.9% (CM). The density, refractive index, colour, smoke point, viscosity, acidity, saponification value, iodine value, fatty acid methyl esters, sterols, tocopherols (by high‐performance liquid chromatography), peroxide value, Eequation/tex2gif-stack-1.gif at 232 nm and the susceptibility to oxidation measured by the Rancimat method were determined. The oil was found to contain high levels of unsaturated fatty acids, especially oleic (up to 76.40%). The dominant saturated acids were behenic (up to 6.01%) and palmitic (up to 6.21%). The oil was also found to contain high levels of β‐sitosterol (up to 52.19%%of total sterols), stigmasterol (up to 16.53% of total sterols) and campesterol (up to 14.26% of total sterols). α‐, β‐ and δ‐tocopherols were detected up to levels of 98.00, 44.50 and 82.41 mg/kg of oil, respectively. The reduction of the induction period (at 120 °C) of M. stenopetala seed oil ranged from 29.4% to 54.7% after degumming. The M. stenopetala seed oil showed high stability to oxidative rancidity. The results of all the above determinations were compared with those of a commercial virgin olive oil and Moringa oleifera seed oil. 相似文献
64.
Chris S. McDonald 《Software》1987,17(10):685-700
Command interpreters under the UNIX operating system typically employ the syntax and semantics of imperative programming languages. Many of the advantages that functional programming languages hold over imperative languages can be incorporated in a functional command interpreter. Unfortunately, functional command interpreters to date have used the syntax of Backus's FP. The advantages of command expressiveness and composition have not been appreciated. A powerful functional command interpreter, fsh, that overcomes many of the deterrents of previous functional command interpreters is presented. Much of the unnecessary complexity of existing UNIX command interpreters is avoided by following the functional paradigm. fsh has been implemented under the UNIX 4.2BSD and System V operating systems. 相似文献
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Nuchanart Suealek Thipaporn Tharavanij Robert M. Hackman Carl L. Keen Roberta R. Holt Benjapun Burawat Ammara Chaikan Rattana Tiengtip Panadda Rojpibulstit 《European Journal of Lipid Science and Technology》2021,123(2):2000126
The potential cardiovascular benefit of virgin olive oil (VOO) is widely recognized. However, the use of VOO at very high cooking temperatures makes these oils poorly suited for many Asian dishes. The use of tea seed oil (TSO) is increasing in Thailand, with TSO having a higher smoke point than VOO. The current study examines the effects of daily TSO intake in healthy adults. In a randomized, single-blind crossover design, 12 men consumed for 3 weeks 40 g day−1 of food prepared with either TSO or VOO as a cooking oil. Plasma lipids, thiobarbituric acid reactive substances (TBARS), and oxidant defense enzyme activities are measured before and after each 3-week intervention period. Gas chromatography analysis of TSO and VOO demonstrates that both oils are equally high in monounsaturated fatty acid. The dietary incorporation of TSO and VOO for three weeks reduces low-density lipoprotein cholesterol (LDL-C) concentrations by 15% and 13%, respectively; with total cholesterol (TC) levels lowered by 10% in both groups. No significant changes in TBARS or antioxidant enzyme activity is observed. These results support the concept that Thai TSO can be utilized as a suitable and healthy alternative oil for high-temperature cooking in many Thai and Asian diets. Practical Applications: Tea seed oil from Camellia oleifera grown in Thailand has been recently reported to favorably lower lipid profiles in hamsters fed a high-fat diet in a manner similar to feeding refined olive oil or grapeseed oil. A pilot crossover trial is conducted to compare the effects of three weeks of daily intake of either TSO or VOO in healthy human adults. Consumption of both oils produced significant reductions in TC and LDL-C. Thai TSO leads to favorable lipid profiles and is a reasonable choice for many Thai and Asian food recipes. 相似文献
68.
在转炉炼钢过程中,石灰快速溶解对转炉高效脱磷具有十分重要的意义,石灰溶解过程中熔渣/石灰界面处形成的2CaO·SiO2产物层被认为是阻碍石灰溶解的关键因素。制备了具有两种不同CO2含量的部分煅烧石灰石,采用浸泡法研究了部分煅烧石灰石在转炉初渣中的溶解行为,并与纯石灰、石灰石的溶解行为进行比较。结果表明,石灰石溶解时在液态熔渣中CaO的传质系数为石灰的2.1倍,残留CO2质量分数为10%的部分煅烧石灰石的传质系数高达石灰石的6.7倍。在CO2质量分数为0~43.5%时,石灰的溶解速率先增大后减小。石灰溶解过程中形成的2CaO·SiO2层严重阻碍了FeOx的扩散,从而减缓了石灰的溶解。与石灰不同,石灰石分解产生的CO2能够破坏2CaO·SiO2层并破坏自身结构,有利于熔渣的渗透,这也适用于残留CO2的部分煅烧石灰石。制备纯石灰的过程中为了确保石灰芯部完全煅烧,因此极易导致石灰外表面发生过烧,而制备部分煅烧石灰石能在一定程度上解决表面过烧的问题。此外,与石灰石相比,部分煅烧石灰石由于表面是石灰外壳,溶解初期其表面附近的炉渣温降相对更低,能够避免溶解初期出现停滞阶段。在转炉富余热量有限的情况下,部分煅烧石灰石的石灰替换比高于石灰石,这取决于部分煅烧石灰石中的CO2残留量。 相似文献
69.
针对于PASSATGP雾灯壳体模具结构设计进行了探讨。采用了先进的热流道技术,可以缩短加工周期,提高加工质量,节约材料,降低成本。 相似文献
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