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481.
S. F. Hachicha S. Barrek T. Skanji H. Zarrouk Z. G. Ghrabi 《Chemistry of Natural Compounds》2009,45(3):304-308
In the present study analyses concerning the composition of vitamin E, sterols, triglycerides, and fatty acids of three Teucrium species (Teucrium alopecurus, T. nabli, and T. polium) seed oil were performed. Linoleic, linolenic, and palmitic were the major fatty acids. The oil was characterized by a high
amount of phytosterol, wherein clerosterol, sitosterol, and stigmasterol are the main constituents. The amount of tocopherol
is nearly 550 mg/kg of oil, with α-tocopherol as the major isomer. Information concerning the composition of Teucrium seed oil is very important for evaluating the therapeutic effect of this oil.
Published in Khimiya Prirodnykh Soedinenii, No. 3, pp. 261–264, May–June, 2009. 相似文献
482.
483.
Investigation of agglomerated Cu seed on Cu oxidation after chemical mechanical planarization 总被引:1,自引:0,他引:1
After chemical mechanical planarization (CMP), the reason which caused the formation of Cu-oxide defects at the interface between Cu deposit and TaN barrier layer has been studied. The experimental results of atomic force microscopy, secondary ion mass spectroscopy, X-ray diffraction demonstrated that the agglomeration phenomenon was found on Cu seed in the thickness of only 10 nm, thus resulting in the electrodeposited Cu film with more abundant C impurities at Cu/TaN interface and lower (1 1 1)/(2 0 0) ratio compared to the thick one (30 nm). Therefore it caused the Cu deposit with poor corrosion resistance and then the Cu-oxide defects were easily formed after CMP. As a result, the correlation between Cu-oxide defects at the Cu/TaN interface and the agglomeration on Cu seed layer was proposed herein. 相似文献
484.
《Analytical letters》2012,45(11):2049-2067
Abstract The interactions of aqueous solutions of chlorine with some fruit acids (citric acid, DL-malic acid, arid L-tartaric acid) at different pH values were studied. Diethyl ether extraction followed by GC/MS analysis indicated that a number of mutagens (certain chlorinated propanones and chloral hydrate) are present as major products in some of these samples. A number of fruit juices (orange, grape, apple, pineapple, and grapefruit) were also treated with aqueous solutions of chlorine at their pH values. The products were analyzed by GC/MS. The same mutagens that were formed by the pure acids (citric acid and DL-malic acid) were identified as major products in ether extracts of these samples. Another mutagen, dichloroacetonitrile, was also identified as a minor product in some of these juice samples. All of the major products observed in the chlorination of all five fruit juices are potentially derived from reactions of aqueous solutions of chlorine with citric or malic acid and with trace amounts of acetaldehyde and acetone in the juices. The minor product, dichloroacetonitrile, is likely derived from the chlorination of certain amino acids in the fruit juices. 相似文献
485.
基于DCT算法的种子点相位解包算法 总被引:4,自引:1,他引:3
移相干涉术由于其高精度被广泛应用在光学元件的面形测量上,而由移相算法得到的相位数据被包裹在[-π,π]之间。基于区域生长理论的相位解包算法(种子点法)可以高精度地实现连贯区域的相位解包,基于离散余弦变换的最小二乘解包(DCT)算法可以实现矩形区域的相位解包,而实际测量中,经常会碰到被测件的有效区域为非矩形的分离区域。因此,在分析前两种算法优缺点的基础上,提出了基于DCT算法的种子点相位解包算法。首先运用DCT算法对整个包裹相位进行解包,然后运用种子点法分别解包各分离区域,再通过DCT算法求得的种子点干涉级次实现各分离区域解包相位的统一。实验结果表明,该方法克服了种子点法和DCT算法的缺点,可以准确、快速地实现分离区域干涉图包裹相位的解包,且比这两种算法具有更好的稳定性和更高的精度。 相似文献
486.
研究了在铁磁(NiFe)/反铁磁(FeMn)双层膜之间,交换偏置的形成过程和热稳定性,特别是NiFe/FeMn的交换偏置作用与FeMn层晶粒尺寸的关系.和以前作者不同的是,本文方法采用非磁性Ni-Fe-Cr合金作缓冲层材料,改变Cr的含量就可以获得不同晶粒尺寸的反铁磁FeMn层.实验表明,晶粒尺寸较小的FeMn产生较强的铁磁/反铁磁交换偏置场;但是,对于较大晶粒的FeMn层,出现交换偏置作用所要的临界厚度较小.这符合Mauri提出的理论模型.交换偏置场的热稳定性实验表明,具有较大晶粒尺寸的FeMn层给出较
关键词:
交换偏置
热稳定性
反铁磁
晶粒尺寸 相似文献
487.
M. Hidalgo J. Y. Cavaill J. Guillot A. Guyot J. Perez R. Vassoille 《Journal of Polymer Science.Polymer Physics》1995,33(11):1559-1572
Polystyrene (PS) (1)/Poly (n-butyl acrylate (BA)/amide type functional monomer) (2) structured latex particles were prepared through emulsion polymerization varying the hydrophilicity of the functional monomer employed. The second-stage polymerization kinetics, the size and morphology of latex particles, and the location of the functional groups in the final latexes were studied, in order to relate them to the thermomechanical properties of films cast from these latexes. It has been shown that, as expected, increasing the hydrophobicity leads to a better homogeneity in the copolymer formed during the second-stage polymerization, while the more hydrophilic functional monomer partly homopolymerizes in a separate phase. However, the functionalization by all the monomers used in this work, prevents the PS seed particles to form a continuous skeleton (percolated network). Further heat treatments at 140°C do not lead to the formation of a continuous PS phase as for pure BA/pure PS two-stage particles. In addition, some thermally induced crosslinking effects are discussed in relation with the functional monomer location within the particles. © 1995 John Wiley & Sons, Inc. 相似文献
488.
Summary Separation of dansyl and di-dansyl derivatives of amino acids present in natural products (corn seed flour, wheat flour fraction
gliadine) is described. Problems with coelution of derivatization by-products and reagent with some dansyl amino acids (DNS-AA)
were solved. A preconcentration step after derivatization of real sample is described. DNS-AA peak areas for different varieties
of corn seed flour were compared. Di-dansyl histidine is not separated from di-dansyl lysine and didansyl tyrosine. Additional
separation mechanisms have to be introduced to achieve separation of these three species. 相似文献
489.
大孔吸附树脂对葡萄籽原花青素的吸附研究 总被引:14,自引:0,他引:14
对8种大孔吸附树脂对葡萄籽原花青素的吸附洗脱性能进行了筛选实验,并选择其中几种树脂研究其对葡萄籽原花青素的吸附特性及机理,发现NKA树脂是比较好的吸附剂。 相似文献
490.
将分形理论和计算机图象纹理分析技术移植到微生物发酵研究中,对菌落和菌丝本形态的定量描述了探讨,并利用菌种的分维特征作为筛选高产菌株的直观指标,有效地提高了菌种筛选工作的效率与准确度,探讨了沃氏底物霉菌转化的工艺过程,并以生物全息观念与分形理论为依托,在分形尺度上对生物体形态及其发育过程进行了描述,建立起菌体生长的形态动力学模型,并与生长(浓度)动力学模型相结合,设计出可判别理论最佳投料点的酶活描述 相似文献