首页 | 本学科首页   官方微博 | 高级检索  
相似文献
 共查询到20条相似文献,搜索用时 78 毫秒
1.
不同金属离子与色氨酸作用的荧光光谱研究   总被引:2,自引:0,他引:2  
研究了不同金属离子对色氨酸的荧光强度的影响。结果表明,在一定条件下当达到一定浓度时,Cu(Ⅱ),Fe(Ⅲ),Mo(Ⅵ)对色氨酸的荧光有猝灭作用,而此时Zn(Ⅱ),Mn(Ⅱ),Cr(Ⅲ),Co(Ⅱ),Ca(Ⅱ)和Na(Ⅰ)则对色氨酸的荧光几乎没有影响。  相似文献   

2.
可见光谱法研究核酸酶P1与氯化铜(Ⅱ)的相互作用   总被引:1,自引:0,他引:1  
首次采用VIS与酶活性测定的方法,研究了溶液中核酸酶P1与无机氯化铜(Ⅱ)(CuCl2)的直接相互作用。结果发现:在水溶液中核酸酶P1活性中心的Zn(Ⅱ)离子可被外加氯化铜(CuCl2)中的Cu(Ⅱ)部分诱导、交换出来,而Cu(Ⅱ)进入酶的活性中心,形成相应“Cu(Ⅱ)-P1”酶衍生物,并随着溶液pH值的变化,形成酶的衍生物结构亦随之变化,相应地也影响了酶的催化活性。  相似文献   

3.
采用VIS和ICP及酶活性测定等方法,研究铜锌超氧歧化酶(Cu2ZnSOD)与组氨酸钴(Ⅱ)〖Co(His)〗的直接相互作用及外加组氨酸钴(Ⅱ)、磷酸盐对此类相互作用的影响。结果发现,水溶液中原酶活性中心Cu(Ⅱ)和Zn(Ⅱ)离子可被外加的组氨酸钴(Ⅱ)部分诱导,交换出来,而Co(His)。中的Co(Ⅱ)进入酶的活性中心,形成“Co-SOD”酶衍生物各组分,并相应影响了酶的催化活性。与此同时,外加  相似文献   

4.
铜锌超氧化物歧化酶与色氨酸钴(Ⅱ)的相互作用   总被引:1,自引:1,他引:0  
采用VIS、ICP及酶活性测定等方法,研究铜锌超氧歧化酶(Cu2Zn2SOD)与色氨酸钴(Ⅱ)(Co(Trp)^n)的直接相互作用以及外加色氨酸钴(Ⅱ)的量、溶液pH值对此类相互作用的影响。结果发现:在水溶液中原酶活性中心处的Zn(Ⅱ)离子可被外加的色氨酸钴(Ⅱ)部分诱导、交换出来,而溶液中外加的Co(Trp)^n中的Co(Ⅱ进入酶的活性中心,形成“Co-SOD”酶衍生物,并相应影响了酶的催化活性  相似文献   

5.
由氟哌酸与Ni(Ⅱ)、Cu(Ⅱ)、Zn(Ⅱ)的硝酸盐合成了三个未见报道的固态配合物,并用元素分析、摩尔电导、红外光谱、热重分析表征了它们的组成和性质。  相似文献   

6.
采用VIS和 ICP及酶活性测定等方法,研究铜锌超氧歧化酶(Cu2Zn2SOD)与组氨酸钴(Ⅱ)[Co(His)n] 的直接相互作用及外加组氨酸钴(Ⅱ)、磷酸盐对此类相互作用的影响。结果发现,水溶液中原酶活性中心的Cu(Ⅱ)和Zn(Ⅱ)离子可被外加的组氨酸钴(Ⅱ)部分诱导、交换出来,而Co(His)n 中的Co(Ⅱ)进入酶的活性中心,形成“Co-SOD”酶衍生物各组分,并相应影响了酶的催化活性。与此同时,外加组氨酸钴(Ⅱ)及磷酸盐对此类相互作用有着重要的影响  相似文献   

7.
Mn(Ⅱ),Co(Ⅱ)与HSA相互作用的荧光光谱研究   总被引:5,自引:0,他引:5  
用荧光光谱法研究了生理pH和等离子点(pH=5.30)时Mn(Ⅱ)、Co(Ⅱ)与HSA的相互作用。根据Forste非辐射能量转移理论,得到了不同pH时Mn(Ⅱ)、Co(Ⅱ)在HSA中的第一强结合位置与Trp-214残基间的距离。这一结果远大于文献报道值,根据Mn(Ⅱ)、Co(Ⅱ)在HSA中的结合部位及HSA的畴结构对这一显著差异进行了讨论。  相似文献   

8.
我们首次发现的铜锌超氧歧化酶(Cu2Zn2SOD)与氨基酸等发生直接相互作用的现象,是一种前人未研究过的重要的生化新现象[1]。在此新发现的基础上,本文用ICP,VIS,NMR和酶活性测定等方法,又从不同角度拓展研究了Cu2Zn2SOD酶与两类不同化合物,即无机氯化钴(CoCl2)、有机组氨酸钴(Co(Ⅱ)(His)n)的直接相互作用,发现酶活性中心金属离子同样与外加的这两类不同化合物发生相互作用,相应地影响了酶的催化活性。还发现Co(Ⅱ)(His)n比CoCl2与酶相互作用更强、更快,Co(Ⅱ)(His)n中的Co(Ⅱ)更易进入酶中,更影响了酶的催化活性。  相似文献   

9.
叶绿素a锰(Ⅲ)和叶绿素a锰(Ⅱ)的合成和光谱   总被引:5,自引:0,他引:5  
叶绿素a锰(Ⅲ)(Mn(Ⅲ)-Chl-a)由脱镁叶绿素(Pheo-a)和醋酸锰(Ⅱ)合成而得,用反相高效液相色谱法分离纯化,叶绿素a锰(Ⅱ)(Mn(Ⅱ)-Chl-a)用Na2S2O4还原时绿素a锰(Ⅲ)获得,研究了它们的元素分析(EA),紫外可见吸附光谱(UV-Vis)和傅里叶红外吸收光谱(FT-IR)证明了此二种配合物的合成,并给出了(Mn(Ⅲ)-Chl-a)与(Mn(Ⅱ)-Chl-a)的组成分  相似文献   

10.
本文首次合成了过渡金属Co(Ⅱ)、Ni(Ⅱ)、C(Ⅱ)与喹啉-2,3-二甲酰胺形成的三种固体配合物。  相似文献   

11.
Pichler  T.  Knupfer  M.  Golden  M.S.  Fink  J.  Winter  J.  Haluska  M.  Kuzmany  H.  Keshavarz-K  M.  Bellavia-Lund  C.  Sastre  A.  Hummelen  J.C.  Wudl  F. 《Applied Physics A: Materials Science & Processing》1997,64(3):301-305
\chem{Rb_1C_{60}} and dimerised using electron energy-loss spectroscopy in transmission. From the excitation spectra a reduced density of states is observed for polymerized . This is in contrast to and can be explained by the different type of \squt{doping} and by the different bonding between the fullerene molecules in the two systems. Additional information about the optical properties was obtained from the low energy loss function. Using a Kramers-Kronig analysis, the dielectric function, (), and the optical conductivity, (), have been derived. and the onset of the spectral weight have been compared between the polymer, the dimer and . This onset of spectral weight is found to be at and for o- and for , respectively. Received: 28 October 1996/Accepted: 13 December 1996  相似文献   

12.
本文在40℃下制得了5-氯水杨醛,使其与硫脲缩合合成了一种含N、O、S的新型Schiff碱配体,该配体与铜(Ⅱ),锌(Ⅱ)能形成稳定的配合物,其组成,结构已由元素分析和红外光谱所表征。  相似文献   

13.
Using the noncentral embedded atom model potential recently proposed by Besson and Morillo for bulk alloys (), we performed computer simulations to predict the ground-state configurations of and clusters (). The computed structures of clusters are in general agreement with such theoretical results as have been obtained by density functional calculations (i.e. for ). The results for Fe-rich clusters show surface segregation of Al, which is in keeping with the findings of a previous study of clusters. Received 29 April 1999  相似文献   

14.
Ab initio calculations of the total dielectronic recombination (DR) rate coefficient of Ni-like barium () and tungsten () in the ground state have been performed using the HULLAC atomic code package. Resonant and nonresonant stabilizing radiative transitions are included. Collisional transitions following electron capture are neglected. The present level-by-level calculations include the DR contributions of all of the levels (over 17000) in the Cu-like inner-shell excited configurations 3d 9 4ln'l' (), 3p 5 3d 10 4ln'l' (), and 3s3p 6 3d 10 4ln'l' (). For both ions, the configuration complexes with a hole in the 3p inner shell contribute almost 10% to the total DR rate coefficient, while the complexes with a hole in the 3s inner shell contribute about 1%. The converging contributions of the 3d 9 4ln'l' (n' > 9) configurations are evaluated by applying the complex-by-complex extrapolation method and are found to comprise up to about 20% of the total DR rate coefficients throughout a wide electron temperature range. The total DR rate coefficients are fitted to an easy-to-use analytic expression which reproduces the original data with an accuracy of about 2% or better in a very wide temperature range. Received: 1 February 1999  相似文献   

15.
A new series of lead (II) complexes have been synthesized with Schiff bases derived from isatins and amino acids. These ligands act as bidentate species and coordinate to the metal atom through the azomethine nitrogen and carboxylate oxygen atom via deprotonation. The synthesized complexes have been characterized by elemental analysis, conductance measurements, and molecular weight determinations. The mode of bonding of the complexes has been suggested on the basis of infrared, UV-visible, and 1H- and 13C-NMR spectroscopy, and probable structures have been assigned to these complexes. Few representative ligands and metal complexes have also been screened for their antifungal and antibacterial activities. Molecular modeling and analysis for bond lengths and bond angles have also been carried out for one of the representative compound, [Pb(L3)2], to substantiate the proposed structures.  相似文献   

16.
运用G98W ,采用Lanl2dz基组 ,对茂金属配合物 [(eat5 C5H4R)Mo(CO) 3 ]2 (R :SiMe3 ,Si2 Me5)进行从头算研究 ,探讨配合物结构单元的稳定性、分子轨道能量、原子净电荷布居规律 ,以及一些前沿分子轨道的组成特征等 ,结果表明 ,标题配合物结构在能量上是稳定的 ,作为结构单元而存在 .  相似文献   

17.
Several functionalized β-diketones and their europium complexes have been synthesized and characterized. The UV-Vis absorption, photoluminescent spectra, thermal and electrochemical properties of these complexes were investigated. The thermal analysis shows that the complexes have good thermal stability. By introducing the number of extended phenyl rings we succeeded in obtaining europium complexes with extremely high photoluminescent quantum yield (PLQY) in solution due to strong site isolation effect.  相似文献   

18.
李改枝  红霞 《光谱实验室》2001,18(3):394-397
本文系统地研究了EDTA,NTA,CyDTA,TTHA与镨,钕,钐,铕,锹,铒络合物的可见光吸收光谱及三阶导数光谱,并以Nd,Ho-TTHA体系测定了混合稀土氧化物中的Nd,Ho,首次以Sm-DTPA体系的三阶导数我谱成功地进行了纯氧化镧中杂质氧化钐的测定。  相似文献   

19.
钕、钐-邻苯二甲酸-1,10-邻菲咯啉配合物的合成及谱学性质   总被引:14,自引:0,他引:14  
合成了稀土钕、钐的邻苯二甲酸 1,10 邻菲咯啉二元、三元配合物 ,通过元素分析、1HNMR、中红外光谱、差热 热重分析 ,确定了配合物的组成为RE2 L3 ·2H2 O ,RE2 L3 phen·2H2 O(RE :稀土离子 ,L :邻苯二甲酸根 ,phen :1,10 邻菲咯啉 ) ,讨论了配合物的谱学性质 ,并对配合物的远红外光谱、拉曼光谱进行了归属研究。  相似文献   

20.
The Pd(II) and Pt(II) complexes with two dibasic tridentate ligands viz. o-vanillin thiosemicarbazone and o-vanillin-4-phenylthiosemicarbazone, have been synthesized and characterized on the basis of their elemental analysis, magnetic susceptibility, conductance, ir and electronic spectral and thermogravimetric data. The presence of chlorine atom in the coordination sphere imparts a square planar geometry to these complexes having the general formula [M (L) Cl]. The mixed ligand complexes of the type [M (L) py. H2O] have also been prepared employing pyridine as an additional heterocyclic base. The complexes are square pyramidal and the presence of chlorine, water molecules is revealed by the study of their thermograms supported by the presence of relevant bands in their ir spectra. Suitable structures have been assigned to these binary and ternary complexes.  相似文献   

设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号