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针对稀土离子具有特征颜色的P507-RECL3萃取分离体系,给出一种基于稀土离子颜色特征识别的组分含量检测方法。首先,通过对稀土离子颜色特征随组分含量的不同而呈现不同变化的分析,表明稀土组分含量与其颜色特征之间存在一定关系。为定量描述组分含量与颜色特征之间的关系,提取H分量直方图作为其颜色特征,并计算其一阶矩统计值,使抽象的颜色特征数值化,最后,利用最小二乘法拟合组分含量与H分量一阶矩统计值之间的函数关系,建立了分段拟合模型,并对模型的有效性进行了验证。结果表明,在单一组分占主要含量时,相对误差能控制在2%以内,具有较高的检测精度,为稀土组分含量的在线检测提供一种新的途径。 相似文献
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基于LS-SVM的稀土萃取组分含量软测量 总被引:1,自引:0,他引:1
为了解决稀土萃取分离过程元素组分含量在线检测的难题, 提出了稀土萃取过程组分含量的一种最小二乘支持向量机(LS-SVM)软测量方法. 利用量子粒子群算法来优化LS-SVM的参数及核函数参数. 仿真结果表明, 所提出的软测量方法是有效的, 比已有的神经网络软测量方法能更好的实现稀土萃取过程中元素组分含量的在线估计. 相似文献
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采用解析电子轰击质谱对电弧法合成的稀土富勒烯衍生物的提取液进行了质谱分析,有效地检测到富勒烯,稀土富勒烯单电荷、双电荷的分子离子峰。利用同位素贡献确证了某些稀土富勒烯的生成。采用高电流瞬间解析样品,使得谱图中的谱峰强度更加真实地反应出提取液中各组分的相对含量。 相似文献
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稀土萃取分离过程自动控制研究现状及发展趋势 总被引:9,自引:2,他引:9
在简要描述稀土萃取分离生产过程的基础上,综述了目前国内外稀土萃取分离过程中稀土元素成分在线检测的方法、装置及其应用现状;稀土串级萃取分离生产过程的计算机流程模拟以及稀土萃取生产过程的自动控制方法、技术及其应用现状.指出了稀土元素组分含量的软测量方法,以综合生产指标为目标的稀土萃取分离生产过程优化控制方法以及由生产过程管理系统和过程控制系统两层结构组成的稀土萃取分离生产过程综合自动化系统已成为稀土萃取分离生产过程自动化未来发展的方向. 相似文献
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稀土生物效应研究(Ⅰ) 总被引:11,自引:1,他引:10
采用ICP-MS及FPLC等技术研究了正常人血浆中稀土含量及其物种分布。结果表明,正常人血浆中含有妆胆的稀土,每种稀土含量与其天然丰度一致;稀土物种主要集中于大分子蛋白组分中,与免疫球蛋白G(IgG)、运铁蛋白(Tf)、血清白蛋白(Alb)等均有作用,其中Tf结合稀土量较多。 相似文献
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采用ICPMS及FPLC等技术研究了正常人血浆中稀土含量及其物种分布.结果表明,正常人血浆中含有痕量的稀土(总量为14133μg/L),每种稀土含量与其天然丰度一致;稀土物种主要集中于大分子蛋白组分中,与免疫球蛋白G(IgG)、运铁蛋白(Tf)、血清白蛋白(Alb)等均有作用,其中Tf结合稀土量较多 相似文献
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利用浸渍法制备稀土改质催化剂,用于废食用油脂催化裂解的裂解气催化改质。考察了催化剂活性组分含量、硅铝比、焙烧温度、改质反应温度对产物组成、烯烃含量及收率的影响。得最佳条件:ZSM-5作为催化剂载体,催化剂活性组分镧稀土含量为6%,催化剂焙烧温度为550℃,改质反应温度为360℃。在最佳条件下催化改质,燃料油烯烃含量降低了34.3%,汽油含量提高了14.36%,轻柴油含量提高了1.67%,重柴油含量下降了6.72%,重油含量下降了2.2%,燃料油总收率提高了7.12%,油品质显著提高。 相似文献
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Uroš Grošelj Mojca Žorž Amalija Golobič Branko Stanovnik Jurij Svete 《Tetrahedron》2013,69(52):11092-11108
A new and simple synthesis of novel N-protected methyl 5-substituted-4-hydroxypyrrole-3-carboxylates, which exist in equilibrium with their 4-oxo tautomers, has been developed in two steps starting from N-protected α-amino acids. The key intermediates are enaminones, which can also be isolated, characterized, and used for the construction of other functionalized heterocycles, before they spontaneously decompose to pyrrole products. 4-Hydroxypyrroles are prone to partial aerial oxidation but can be efficiently alkylated or reduced to stable polysubstituted pyrrolidine derivatives. 相似文献
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The chemoselectivity in the intramolecular CH insertion of various diazosulfonamides has been experimentally studied. The results reveal that the aliphatic 1,4-, 1,5-, or 1,6-C(sp3)?H insertions of diazosulfonamides are not accessible, while the aromatic 1,5-C(sp2)?H insertion can be realized specifically by adjusting the diazo-adjacent group. In addition, the general chemoselectivities in the intramolecular CH insertions of diazosulfonyl compounds are summarized. Generally, diazosulfones undergo both aromatic 1,5-C(sp2)?H and aliphatic 1,5- and 1,6-C(sp3)?H insertions, while diazosulfonates undergo aliphatic 1,5- and 1,6-C(sp3)?H insertions. However, diazosulfonamides only undergo aromatic 1,5-C(sp2)?H insertion. 相似文献
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N-Heterocyclic carbene-palladacyclic complexes 3 were successfully achieved in a one-pot procedure under mild conditions. The structure of 3a was unambiguously confirmed by X-ray single crystal diffraction and it was an active catalyst in the Buchwald-Hartwig amination and α-arylation of ketones even at very low catalyst loadings (0.01?mol%). 相似文献
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Shashikant U. Dighe Surya K. Samanta Shivalinga Kolle Sanjay Batra 《Tetrahedron》2017,73(17):2455-2467
An efficient iodine-mediated oxidative Pictet-Spengler reaction in dimethyl sulphoxide (DMSO) using terminal alkynes as the 2-oxoaldehyde surrogate for the synthesis of aryl (9H-pyrido[3,4-b]indol-1-yl)methanones is described. The scope of the protocol includes the total synthesis of Fascaplysin, Eudistomins Y1 and Y2. The methodology is extended for preparing pyrrolo[1,2-a]-quinoxaline and indolo[1,5-a]quinoxaline derivatives. The utility of 1-aroyl-β-carbolines was demonstrated by performing palladium-catalyzed β-carboline directed ortho-C(sp2)-H functionalization of the phenyl ring with thiomethyl (SMe) group using DMSO as source and for accessing 4-aryl-canthin-6-ones. 相似文献
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In this Letter, we described a facile method for constructing fused bicyclic 1-arylpyrazol-5-one ring system. We employed various methylene-containing carboxylic acids as the substrates and proved that the pyrazolone ring closure requires activated methylene group in intermediate II. Accordingly, a series of structurally diversified, fused bicyclic 1-arylpyrazol-5-ones was prepared in moderate to high yields using the requisite substrates. 相似文献
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An efficient approach to the synthesis of highly congested di, penta and hexacyclic pyrazoles as well as imidazole fragment containing novel heterocyclic molecule has been developed through a carbanion induced transformation of suitably functionalized 2H-pyran-2-ones, benzo[h]chromene and thiochromeno[4,3-b]pyrans. Due to the presence of fluorescence, we report their prime application metal sensor as off/on switching in ferric ions. 相似文献
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Synthesis of substituted pyrrolo[1,2-a]pyrazines and pyrazino[1,2-a]indoles from the Morita-Baylis-Hillman derivatives of acrylates via saponification followed by Curtius reaction is described. 相似文献
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用正丁胺作为碳源,采用射频辉光放电制备碳膜,选用激光染料R6G和聚乙二醇混合液作为蒸气源,采用单源热蒸发,在蒸发室与染料同时沉积得到混合膜,用拉曼光谱和红外光谱分析了碳膜的结构和键合方式,分析表明:碳膜中存在胺基团和氢原子.混合膜的荧光谱测量结果表明,认为正丁胺对染料荧光谱的影响是因为胺基和氢原子的存在. 相似文献
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An efficient tandem approach for the selective synthesis of 4,5-dihydroimidazo[1,5-a]quinoxalines 6a–g and imidazo[1,5-a]quinoxalines 7a–h by the reaction of 2-imidazolyl anilines 4a–c with aryl aldehydes 5a–k under mild reaction conditions is described. Introduction of electron releasing alkyl groups in substrates 4a–b was found to be instrumental for the success of the reaction. 相似文献
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The Diels-Alder reactivity of 1,2-heteroborines (H4C4B(H)X, X?=?NH, PH, AsH; O, S, Se) has been computationally explored by means of Density Functional Theory (DFT) calculations. The influence of the HB?=?X fragment on the reactivity of the system has been quantitatively analyzed in detail by means of the so-called Activation Strain Model (ASM) of reactivity. It is found that the interaction between these species and the dienophile is significantly stronger than that computed for their all-carbon isoelectronic counterpart, benzene. In addition, the strain energy plays a key role in the observed reactivity trends. The role of the aromaticity strength of these heteroarenes on the reactivity is also assessed. 相似文献