979 resultados para CAST MG-ZN


Relevância:

20.00% 20.00%

Publicador:

Resumo:

研究了稀土离子对肌质网(Ca~(2+)+MG~(2+))-ATP酶活性的影响及其作用机制,结果表明,低浓度Gd~(3+)对肌质网膜上(Ca~(2+)+Mg~(2+)),ATP酶有激活作用,较高浓度Gd~(3+)抑制其活性,Gd~(3+)抑制纯化酶的活性,低浓度Gd~(3+)对磷脂酸(FA)、心磷脂(CL)重组酶有激活作用,而对磷脂酰胆碱(PC)、磷脂酰胆碱(PC)与磷脂酰乙醇胺(Pe)混合物(PC/PE)及磷脂酰丝氨酸(PS)重组酶无激活作用,低浓度Tb~(3+)对肌质网膜与纯化酶上Ca~(2+)结合位点的影响不同。

Relevância:

20.00% 20.00%

Publicador:

Resumo:

Alkaline earth (Mg, Ca. Sr) yttrium silicate oxyapatites doped with Eu3+ show red luminescence with comparable intensity. In this system of phosphors, the Eu3+ ions enter 4f sites and 6h sites simultaneously according to the fluorescence spectra, in which

Relevância:

20.00% 20.00%

Publicador:

Resumo:

钙钛矿型复合氟化物ABF_3(A=Li,Na,K,Rb;B=Mg,Ba,Zn等)是固体可调谐激光的优良基质材料,人们对其辐照损伤已有较多研究,但其中关于BaLiF_3的研究相对较少,特别是用ESR方法研究BaLiF_3的辐照损伤尚未见报道.近年来,人们在适应新的高能粒子加速器需求的新型无机闪烁材料的过程中发现BaLiF_3具有一定的应用前景,在这一应用中对材料的抗辐照性能有很高的要求.本文报道了用ESR方法研究BaLiF_3微晶受X射线和γ射线

Relevância:

20.00% 20.00%

Publicador:

Resumo:

以Mg(NO3)2、Ca(NO3)2、Eu(NO3)3、Bi(NO3)3、LiNO3和Si(OC2H5)4为反应物,采用溶胶-凝胶法,在比较低的温度下,首次合成0.701moIMgO-0.175molCaO-1.25moISiO2∶0.06molEu(3+),0.002moIBi(3+)(加入Li+作为电荷补偿剂)发光体。得到了最佳合成条件。研究了由溶胶向凝胶转变和凝胶向发光晶体的转变过程。探讨了发光体在不同激发波长激发下的发光特性以及在激活剂、敏化剂不同掺杂量下的发光行为。讨论了在(Mg(a)O-SiO2基质中Bi(3+)对Eu(3+)的能量传递和敏化作用。

Relevância:

20.00% 20.00%

Publicador:

Resumo:

[Si(W2O7)(6)](8-) pillared LDH structure hydroxides were synthesized by the method of restructuring of the thermally decomposed hydrotalcite-like compounds for Zn-Al and Mg-Al oxide systems. [P(W2O7)(6)](8-) pillared Ni-Al LDH structure hydroxide was synt

Relevância:

20.00% 20.00%

Publicador:

Resumo:

本文利用键子式方程和有效价电子电荷的概念详细计算了立方钙钛矿型KMF_3(M=Mg、Mn、Co、Ni、Zn)晶体的化学键参数,键性,晶体中离子的半径及离子的电子极化率,结果发现,F离子在晶体中产生形变,形变行为和F的极化率以及化学键的共价性有相同的规律。

Relevância:

20.00% 20.00%

Publicador:

Resumo:

本文研究了长白山自然保护区大气降水(雨水或雪水)中的多元素分析。采用ICP-AES法测定水中的K、Na、Ca、Mg、Mn、Fe、Sr、Ba、Cu、Zn、Ni和V等元素,用干扰系数法对光谱干扰进行修正。为该地区天气环境背景值和大气污染现状提供了富贵资料。

Relevância:

20.00% 20.00%

Publicador:

Resumo:

本文用差示扫描量热(DSC)、热重(TG)和红外光谱法研究了标题配合物(简记为C_9M)的热稳定性和固—固相变.讨论了中心金属离子对热稳定性和相变的影响.发现其热稳定性依C_9Co>C_9Mn>C_9Zn>C_9Cu降低.固—固相变数目、相变温度和相变的有序—无序效应主要取决于中心金属离子的种类。Zn组配合物总相变的无序效应比Cu组高,在高温相为完全无序相。C_9Zn配合物低温相变(285K)主要来源于链间相互作用和堆积态的有序—无序变化.高温相为“链熔化”态.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

本文用循环伏安法发现了中性载体ETH129(N,N,N′,N′-四环己基-3-氧杂-戊二酰胺)在水/硝基苯界面推动H~+,Li~+,Na~+,Zn~(2+),Mg~(2+),Cn~(2+)的离子转移,对推动离子转移过程的机理进行了探讨,测定了相应离子的扩散系数和其配合物的稳定常数。

Relevância:

20.00% 20.00%

Publicador:

Resumo:

本文从静态和动态两个方面探讨了各种实验条件对新型分离富集剂吸附能力的影响。结果表明:在静态条件下,Cd~(2+)和Zn~(2+)的吸附平衡时间为1h,Pb~(2+)和Cu~(2+)为1.5h;富集剂对上述几种离子的吸附速度的顺序是:Pb~(2+)>Cu~(2+)>Zn~(2+)>Cd~(2+);当[Mg~(2+)]<200mg/L,[Ca~(2+)<400mg/L,[K~+]<350mg/L时,此三种金属离子不会干扰对Cu~(2+)的吸附。对于动态吸附,当吸附剂用量为0.1g(对Hg~(2+)),或0.15g(对Cu~(2+)),pH为0.3—8(对Hg~(2+)),3~8(对Cu~(2+))及流速>7mL/min(对Hg~(2+)),或≤10mL/min(对Cu~(2+))时,本富集剂可完全吸附上述两种物质。另外,此富集剂的饱和吸附量为巯基棉的3—20倍,具有很高的吸附能力和很好的稳定性。

Relevância:

20.00% 20.00%

Publicador:

Resumo:

Epitaxial crystallization of high-density polyethylene (HDPE) on isotactic polypropylene (iPP) in solution-cast films has been investigated by electron microscopy. The specimen-tilt technique of electron microscopy has been used to study the structural relationship between HDPE and iPP crystals. HDPE exhibits different crystalline morphologies in the two basic types of iPP spherulite textures, cross-hatched and lathlike regions. In the former, the crystallographic c axis of HDPE lamellae is in the film plane, while in the latter, the c axis of HDPE crystallites is at an angle of about 50-degrees with the normal of the film. In both structural regions of iPP, however, the contact planes of epitaxial growth are (0 1 0) for iPP and (1 0 0) for HDPE.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

Thin films of PSt/PMAA and PEO-PSt-PEO block polymers were deposited on a polystyrene substrate by solution adsorption (with or without solvent treatment), and the film surfaces were characterized by means of XPS. Direct solvent - casting of PEO-PSt-PEO from benzene solutions resulted in PSt-rich surfaces, whereas PMAA richer surfaces were obtained for PSt/PMAA films cast from DMF solutions. Moreover, solvent treatment after casting had profound effect on the film surface composition. Treatment with water markedly increased the surface concentration of polar PEO segments. In the case of PSt-PMAA block polymers, the PSt content on the surface increased in the order of water < ethanol < cyclohexane < petroleum ether, the last-named giving films with almost pure PSt surface. It is well worth noticing that the bulk composition had little to do with the surface composition for both PSt/PMAA and PEO-PSt-PEO block polymers within the composition range investigated when subsequent solvent treatment was applied.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

对18例克山病患者及43例健康人心肌 Ba、Ca、Cd、Co、Cr、Cu、Fe、K、Mg、Mn、Na、P、Ti、Zn 和 Se 含量的两个均值向量进行了比较,结果表明其差异非常显著(P<0.01)。对应分析取最大的两个特征根(其和超过全部特征根之和的85%)绘成二维图,可见:克山病组与健康组分界明确;Se、Zn、Cu、P、Mg 和 K 与健康组关系密切;Ca、Co 和 Na 与克山病组关系密切;Ba、Fe、Mn、Ti、Cd 和 Cr 似乎与两组关系都不密切。

Relevância:

20.00% 20.00%

Publicador:

Resumo:

本文介绍了我们研制的稀土作为微量添加元素的中等强度Al-Zn-Mg合金,对其制备工艺、性能和稀土的作用进行了研究和讨论。研究表明,该合金具有强度较高,高温塑性好,可焊性优良等特点,适用锻压,挤压等变形加工。可望在交通车辆等方面获得应用。

Relevância:

20.00% 20.00%

Publicador:

Resumo:

明胶是感光工业基本原料之一,其质量的好坏直接影响照像性能,因此对明胶中的杂质进行分析研究具有重要的实际意义。本文采用火焰原子吸收光谱法测定明胶中Mg、Ca、Cu、Fe四个元素。明胶样品经灰化除去有机成分后进行酸溶,然后定容到