1000 resultados para Interleukine-8


Relevância:

20.00% 20.00%

Publicador:

Resumo:

We present the synthesis of the AgLnMo(2)O(8) oxides with Ln = La-Nd, Sm, Gd, Tb and Y. These compounds represent a scheelite-related structure type characterized by MoO42- tetrahedrons. The IR spectra show three transmittance bands in the region of 1000-400 cm(-1), which correspond respectively to the nu(1), nu(2), and nu(3) modes of the tetrahedral MoO42- groups. All of AgLnMo(2)O(8) are insulator materials at room temperature. The temperature dependence of the magnetic susceptibilities of AgLnMo(2)O(8) (Ln = Ce-Nd, Sm, Gd, Tb) show Curie-Weiss Law behaviors with two anomalies occurring at low temperature, whereas AgLaMo2O8 and AgYMo2O8 both exhibit diamagnetic properties as expected. The magnetic moments at room temperature fit very well with those corresponding to rare earth sesquioxides. This suggests that rare earth ions exist in +3 oxidation state in all AgLnMo(2)O(8) compounds.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

LnCl(3) reacted with C6H5CH2C5H4Na in THF (tetrahydrofuran) in the ratio 1.1 at room temperature for 1 h giving C(6)H(5)CH(2)C(6)H(4)LnCl(2) . nTHF, which reacted with C8H8K2/THF and the crystals obtained were recrystallized in DME to yield the title complex. The crystal structure of (C8H8) Ln (C6H5CH2C5H4). DME was determined revealing that the Gd complex has one conformation. One benzylcyclopentadienyl (eta(5)), one cyclooctatetraenyl (eta(8)) and the two oxygen atoms of DME (dimethoxyethane) are coordinated to Gd with the effective coordination number of 10.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

制备了钴(Ⅱ)邻菲咯啉、8-羟基喹啉配合物/Y型分子筛;利用元素分析、TG-DTA、SEM、UV-Vis、BET及XRD等方法确定了分子筛笼中金属配合物的生成及其晶体结构;考察了实验参数对苯酚转化率及产物选择性的影响。

Relevância:

20.00% 20.00%

Publicador:

Resumo:

制备了铁邻菲咯啉、8-羟基喹啉配合物/Y型分子筛(简记为FePhen/Y,FeO_x/Y).用元素分析,TG-DTA,UV-Vis,IR,SEM,BET,及XRD等方法确定了分子筛笼中金属配合物的生成及其晶体结构,考察了实验参数对苯酚转化率及产物选择性的影响.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

制备了铬(Ⅲ)邻菲咯啉、8-羟基喹啉配合物/Y型分子筛,利用元素分析、SEM、UV-Vis、BET及XRD等方法确定了分子筛笼中金属配合物的生成及其晶体结构,考察了实验参数对苯酚转化率及产物选择性的影响。

Relevância:

20.00% 20.00%

Publicador:

Resumo:

We present the synthesis of AgLnMo(2)O(8) compounds with Ln = La-Nd and Sm. These compounds represent a scheelite-type structure characterized by MoO4- tetrahedrons. IR spectra show five absorption peaks in the region of 1000-400cm(-1), around 800cm(-1) and 400cm(-1), which correspond to the modes of the tetrahedral MoO42- groups. All of AgLnMo(2)O(8) (Ln = La-Nd and Sm) oxides are dielectric materials at room temperature. The temperature dependence of the magnetic susceptibility ofAgLnMo(2)O(8) (Ln = Ce-Nd and Sm) shows Curie-Weiss law behavior from 100K to 300K. This indicates that both Ce and Pr exist in +3 oxidation state in AgLnMo(2)O(8). For AgLaMo2O8, diamagnetic properties are found as expected.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

In this paper, the luminescence properties of Eu3+ and Dy3+ in the oxyapatites M(2)RE(8)(SiO4)(6)O-2 (M=Mg, Ca; RE=Y, Gd, La) were studied. The spectral characters of Eu3+ were discussed in relation to the crystal structure. The dependence of the red-to-orange intensity ratio and the position of the charge transfer band of Eu3+ and the yellow-to-blue intensity ratio of Dy3+ together with their fluorescence intensities (I-R for Eu3+ and I-Y for Dy3+) On the M(2+) and the substitution of BO45- and PO43- for SiO44- was discussed. Finally, the concentration quenching of Dy3+ luminescence was reported.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

本文研究了镥-Ferron-表面活性剂三元荧光体系的荧光特性,各种表面活性剂中以溴化十六烷基三甲铵的增敏效果最佳,与相应的二元体系相比较,灵敏度提高近10倍。镥的测定下限可达8.8ng/ml。本法与P_(507)萃取色谱分离法相结合可用于天然混合稀土氧化物中痕量镥的测定,结果较满意。

Relevância:

20.00% 20.00%

Publicador:

Resumo:

研究并比较了十二烷基苯磺酸钠(SDBS)对Bi(Ⅱ)-、Pb(Ⅰ)-8-羟基喹哪啶,Cu(Ⅰ)-、Cd(Ⅰ)-、Zn(Ⅰ)-乙二胺体系示波极谱电流的增敏效果,和对峰电位的影响及有关试验。表明SDBS只对能形成螯合阳离子者起增敏作用,其增敏程度则受SDBS在电极表面与相应螯合阳离子是形式缔合物,还是因超载静电吸引产生诱导吸附作用所制约。前者最佳可增敏达60余倍,后者最佳可增敏10余倍。

Relevância:

20.00% 20.00%

Publicador:

Resumo:

物质的硬度作为一个物理量已被广泛运用于各种研究领域。硬度测量在各种机械试验法中是最迅速、最经济的一种方法,而且材料硬度值与其它机械性能有一些相当精确的相应关系。有关硬度的各种测试方法已发展相当完善。同时,人们对硬度的微观机制也曾作了许多

Relevância:

20.00% 20.00%

Publicador:

Resumo:

自1969年首次报道稀土环辛四烯基化合物Eu(C_8H_8)和Yb(C_8H_8)的合成以来,相继合成K[Ln(C_8H_8)_2],[Ln(C_8H_8)Cl·2THF]_2和[Ln(C_8H_8)·2THF]等,还报

Relevância:

20.00% 20.00%

Publicador:

Resumo:

The tetranuclear nearly-linear complex (eta-8-C8H8)Er(mu-eta-8-C8H8)K(mu-eta-8-C8H8)Er(mu-eta-8-C8H8)K(THF)4 (THF = tetrahydrofuran) is first synthesised by the reaction of benzylcyclopentadienyl erbium dichloride (PhCH2C5H4)ErCl2.3THF with cyclooctatetraenyl potassium K2C8H8 in 1:1 molar ratio in THF; a single crystal X-ray study has shown that the complex has the tetralayer-sandwich structure and that the adjacent Er3+ and K+ ions are bridged by eta-8-cyclooctatetraenyl group.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

LnCL3 reacts with NaC5H5 and K2C8H8 to yield the complexes (eta-5-C5H5)Ln(eta-8-C8H8).nTHF (Ln = Pr, Nd, n = 2; Ln = Gd, n = 1) and LnCl3 reacts with KC9H7 and K2C8H8 to yield the complexes (eta-5-C9H7)Ln(eta-8-C8H8).2THF (Ln = Pr, Nd; eta-5-C9H7 = indenyl); crystallography reveals (eta-5-C5H5)Pr(eta-8-C8H8).2THF and (eta-5-C9H7)Pr(eta-8-C8H8).2THF not to possess the parallel ring sandwich structure.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

我们在晶体化学键的研究中得出这样的结论,晶体硬度正象其他宏观量一样,是其微观特性的宏观反映,我们通过对一些晶体的研究比较,给出了AB型晶体化学键参数和硬度之间的定量关系一经验公式,并对六十多种晶体的硬度进行了计算,结果和实验测定值符合很