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101.
Calaf RE Peña J Paytubi S Blount BC Posada de la Paz M Gelpi E Abian J 《Analytical chemistry》2001,73(16):3828-3837
In 1981, an unknown disease appeared in Spain, the Spanish Toxic Oil Syndrome. Nowadays and despite all efforts, the etiological agent is still unknown. Early studies showed a link between this illness and the consumption of denatured rapeseed oil fraudulently processed and marketed as edible oil. Two families of aniline derivatives present in these oils (fatty acid anilides and acylated phenyl amino propanediol derivatives or PAPs) were found to be good chemical markers of toxic oils. In this work, a new method has been developed to analyze these aniline derivatives in oil samples by HPLC-MS and HPLC-MS/MS with an API source. For their quantification, three different internal standards were used, one for anilides and two for PAPs. Quantification limits were 8 ppm for anilides and 0.2 ppm for PAPs. Anilides and PAPs were found in marker-positive samples at levels up to 50,000 and 330 ppm, respectively. The relative abundance of the different fatty acid anilides and PAPs correlates with the fatty acid composition of the oils. More than 2,600 different samples were analyzed by this method in the most exhaustive screening of suspected toxic oils carried out to date. 相似文献
102.
Seseña S Sánchez-Hurtado I González Viñas MA Palop L 《International journal of food microbiology》2001,67(3):197-205
Trial fermentations were performed using three experimental starter cultures with a view to selecting the most appropriate starter for use in the manufacture of Almagro eggplants. The lactic acid bacterial strains used in the starters had previously been isolated from spontaneous fermentations. The combined action of the obligate heterofermentative species Lactobacillus brevis and the facultative heterofermentative species L. plantarum yielded Almagro eggplants with sensory properties preferred by panelists. Conversely, another obligate heterofermentative species, namely, L. fermentum, present in certain starter formulations tested, appeared to encounter difficulty growing during fermentation and exerted little influence on the sensory characteristics of the eggplants produced. 相似文献
103.
n-Alkane content of intramuscular lipids (Biceps femoris muscle) of the Iberian pig have been determined. Thirty-four pigs, divided into four groups, based in the feeding system (Montanera, fed on acorns and pasture; and Pienso, fed on a concentrate feed) and in the genotype (Iberian pure pigs; and Iberian crossbred with Duroc 50%) were studied. n-Alkane content of intramuscular lipids has not been affected by neither crossbreeding nor feeding, although the analysis of feeds administered to the pigs showed greater n-alkane values in pasture (consumed by animals in montanera), than in acorns and concentrate feed. 相似文献
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The Mig1p repressor from the food yeast Candida utilis has been isolated using a homologous PCR hybridization probe. This probe was amplified with two sets of degenerate primers designed on the basis of highly conserved motifs in the DNA-binding region (zinc-finger domain) from yeast Mig1p and fungi CreA repressors. The cloned gene was sequenced and found to encode a polypeptide of 345 amino acids which shows significant identity with other yeast and fungus repressors in the DNA-binding domain and also with the yeast Mig1 proteins in the C-terminal region (effector domain). The MIG1 repressor gene from C. utilis was able to complement functionally the mig1 mutation of S. cerevisiae. The sequence presented here has been deposited in the EMBL data library under Accession No. AJ277830. 相似文献
106.
采用溶胶-凝胶法制备基于染料吸收原理的光纤化学pH传感膜.通过有机掺杂,获得了对溶液pH具有宽范围动态响应的敏感膜.将四乙氧基硅烷和有机硅单体水解后加入pH指示剂,铺成溶胶-凝胶薄膜.该pH传感器的pH感应范围可达到pH3~11,响应速度3 min,一个月稳定性在RSD<18%. 相似文献
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中国火电厂自动化发展趋势及对策 总被引:16,自引:2,他引:14
110.
有人说,用PPT做课件不够绚,我说不,比如PPT2007里就有非常多的三维图形,配上动画,效果绝对震撼!对,无需动用3DMax,直接用PPT完成。5秒钟制作三维图形在2007中我们可以对所有插入的素材做三维效果(以形状为例)。先介绍一个简单的方法:进入"插入→形状", 相似文献