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921.
荧光钙探针试剂及其在生物分析中的应用 总被引:2,自引:0,他引:2
本文评论了荧光钙探针试剂合成、性质、结构和生物分析应用方面的进展。各种典型的荧光钙探针试剂均已分别加以讨论。 相似文献
922.
本文用反相高效液相色谱法研究了铁、钴,钯-3,5-diBr-PADAT-SLS体系。在pH5.5的HAc-NaAc介质中,七种金属离子可与试剂生成配合物。用Spherisorb 5 ODS柱,含有4.02×10~(-2)mol/L KCl和0.06mol/L pH3.0HAc-NaAc甲醇/乙腈/水(83/0.5/16.5)溶液作为流动相,分离出了Fe~(2+)、Co~(2+)和Pd~(2+)配合物。对分离机理进行了初步研究。建立了铁、钴、钯的同时测定的HPLC-光度法。用于对虾饵料中铁、钴的测定,结果令人满意。 相似文献
923.
合成了18种内-α-取代-α-甲基双环[2,2,1]庚烷-2-基甲醇(Ⅰ)。测定了所有化合物的折光率(或熔点)、质谱、红外光谱、~1H核磁共振谱、气相色谱的保留时间和薄层色谱的比移值。评定了它们的香气,并与相应的内-α-取代-α-甲基双环[2,2,1]-5-庚烯-2-基甲醇(Ⅱ)系列化合物的香气进行了比较,初步探讨了结构与香气的关系。 相似文献
924.
近年来对溶剂革取过程中有机相形成微乳状液的研究正引起人们的重视同,我们曾用付里叶变换红外光谱法研究过钢皂及钾皂2一乙基已基股酸单·2一乙基已基酯(简写为NaA及KA下同)加水形成微乳状液的过程,观察到P二0,P-0-C,P-0-HH-0-H和0-H等基团吸收谱带频率或强度的变化[‘剑.本文进一步对#、销和钾三种碱金属皂化2一乙基已基胁酸单一2一乙基已基酯有机相微乳状液的形成及其红外光谱作深入研究.1实验部分五.1样品的制备问将金属捏、销和钾各置于2一乙基巴基磷酸单一2一乙基已基酯(以HA表示,下同)一正庚烷中加热回流… 相似文献
925.
TiO2(B) nanowires and TiO2 anatase nanowires were synthesized by the hydrothermal processing in 10 M NaOH aq. at 150 °C followed by the post-heat treatment at 300-800 °C. As-synthesized Na-free titanate nanowires (prepared by the hydrothermal treatment and repeated ion exchanging by HCl (aq.) were transformed into TiO2(B) structure with maintaining 1-D morphology at 300-500 °C, and further transformed into anatase structure at 600-800 °C with keeping 1-D shape. At 900 °C, they transformed into rod-shaped rutile grains. Microstructure of these 1-D TiO2 nanomaterials is reported. 相似文献
926.
927.
As a special substance between isolated molecules and condensed phase, clusters have drawn more and more attention by theoreticians and experimentalists. The protonated rare gas cluster is one kind of simplest clusters, which can be looked on as the simplest solution composed of the simplest solute, proton, and the simplest solvent, rare gas. The study on such a system can help us to know more about the complex condensed matter. However, the information for the molecular properties of protonat… 相似文献
928.
Jian-bin Zhang De-zhu Ma Hua Zhong Xiao-lie Luo Department of Polymer Science Engineering University of Science Technology of China Hefei China 《高分子科学》2000,(6):569-572
The surface morphology of free-surface PCL ringed spherulites was investigated by using atomic forcemicroscopy. The spherulites were obtained by crystallization of PCL/PVC blends of different compositions. It was found thatthe ringed spherulite exhibited regularly fluctuating rings on its surface. Compared with the bright-dark ring pattern of thespherulite under a polarizing microscope, it was proved that the optical characteristics of the ringed spherulite underpolarizing microscope coincided with its surface characteristics. The bright rings in polarizing micrographs of the spherulite coincided with the convex rings on its surface, while the dark rings coincided with the concave rings. 相似文献
929.
Bogumil Brzezinski Zbigniew Rozwadowski Teresa Dziembowska Georg Zundel 《Journal of Molecular Structure》1998,440(1-3):73-79
Three di-Schiff bases of 2-hydroxy-5-methyl-isophthalaldehyde with 4-R-anilines (R=H, CH3, OCH3) and their 1:1 complexes with HClO4 were studied by FT-IR, 1H, and 13C NMR spectroscopy in acetonitrile and [2H3]acetonitrile solutions, respectively. In di-Schiff bases intramolecular OH…N hydrogen bonds have been detected; however, they show no proton polarizability. Hydrogen-bonded systems with fast proton fluctuation and large proton polarizability have been found in the 1:1 complexes of di-Schiff bases with HClO4. 相似文献
930.
The new Pd(II), Pt(II), Re(V), Mo(VI) and W(VI) complexes of 2-hydroxynicotinic acid (H2nicO), trans-[PdCl(HnicO)(PPh3)2]·0.75CH3CN (1), K[PdCl(HnicO)2]·H2O (2), [Pd(HnicO)2(bipy)] (3), cis-[PtCl(HnicO)(PPh3)2]·0.75CH3OH·0.5H2O (4), [PtCl(HnicO)(bipy)] (5), cis-[ReOI2(HnicO)(PPh3)] (6), Na2[Mo2O6(HnicO)2]·5H2O (7), Na2[Mo4O12(HnicO)2]·2H2O (8) and Na2[W2O6(HnicO)2]·5H2O (9) have been prepared. The crystal structures of 1 and 4, were determined by X-ray diffraction and show the HnicO− ligand coordinated to palladium or platinum through the nitrogen atom only. Infrared, Raman, 1H and 13C{1H} NMR spectroscopic data for the complexes are presented and are in agreement with the crystallographic results. 相似文献