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蔬菜是烹饪中用得最为广泛的大宗原料,它既可以作为菜肴的主料,也可以作配料,还有的可以作为调料来用。蔬菜之所以具有各种鲜艳的色泽,是因为其自身含有丰富的色素。(1)叶绿素:叶绿素是形成蔬菜颜色的色素,而菠菜、油菜、韭菜、青菜等所含叶绿素比较多。(2)胡萝卜素、叶黄素、番茄红素:它们是形成蔬菜中黄色、红色、橙色的几种色素,尤其是在胡萝卜、番茄、红辣椒当中含量丰富。(3)花青素:花青素是形成蔬菜红色、蓝色、紫色等颜色的色素,比如心里美萝卜、茄子的紫黑色,苋菜的紫红色,都是由花青素构成的。大家都知道,蔬菜在加工和烹调的过程中,其自身的色素 相似文献
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The title compound (13,27-dimethyl-3,6,9,17,20,23-hexaazatricyclo-[23.3.1.1^11,15]-triaconta-1 (29),2,9,11,13,15(30), 16,23,25,27- decaene-29,30-diol-N^3, N^6, N^9, O^29, O^30)-bis (nitrato-O,O')-europium (Ⅲ) nitrate hydrate ([EuL(NO3)2](NO3)·H2O, L denotes the macrocyclic ligand) was prepared and characterized by elemental analysis, infrared spectra, and electrospray mass spectra. Its crystal and molecular structure was determined by X-ray diffraction. The crystal crystallized in the monoclinic system, space group C2/c with a=2.3757 (4) nm, b=1.4302(3) nm, c=1.9584(3) nm, β=91.654(5)°, M=818.60, V=6.651(2) nm^3, Z=8, D=1.635 g/cm, F(000)=3312, R=0.0542, wR=0.1045. The central ion Eu^3+ was nine-coordinated in the coordinaton geometry of a distorted tricapped trigonal prism. The macrocycle was coordinated through two oxygen and three nitrogen atoms. Two nitrate are chelate in the opposite positions of the macrocycle, the third nitrate being ionic. At room temperature, excitation of the title complex gave rise to the characteristic emissions of the Eu^3+ ion. 相似文献
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文章将渐进成形的思想融入到传统的管件电磁胀形工艺中,提出管件电磁渐进成形的新工艺,即采用小尺寸线圈,通过移动多次成形的方式成形长管件。提出了适合于管件电磁渐进胀形工艺的顺序耦合数值模拟方法,并与一次放电、两次放电、三次放电的实验结果进行对比,模拟结果与3组实验数据均吻合。采用数值模拟的方法,进一步研究重叠率和成形顺序对管件变形均匀性的影响,研究结果表明,重叠率为50%、成形顺序为b→c→a时,可获得最佳的成形均匀性。电磁渐进成形技术应用于管件胀形工艺中具有可行性,对实际生产具有指导意义。 相似文献
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合成了2,3,7,8,12,13,17,18-八苄硫基四氮杂卟啉的Co(Ⅱ)、Zn(Ⅱ)配合物,对其进行了元素分析、紫外可见光谱和红外光谱表征,并考察了配体及配合物的循环伏安性质,初步讨论了三个化合物电氧化还原的机理. 相似文献