REE bound DNA in natural plant

The binding of rare earth elements (REEs) with nucleic acids in the leaves of fern Dicranopteris dichotoma (DD) has been studied by molecular activation analysis (MAA). The REEs bound DNA (REE-DNA) was obtained from the leaves of DD. The CTAB-based procedure was modified for extraction of total DNA. The purity of DNA was examined by UV spectroscopy. The DNA obtained was separated and determined by agarose gel electrophoresis further. Meanwhile, the contents of eight rare earth elements (La, Ce, Nd, Sm, Eu,Tb, Yb and Lu) in REE-DNA were detected by instrumental neutron activation analysis (INAA). The results showed that REE-DNA with higher purity could be extracted from plant using this method. It was also found that REEs were bound firmly with DNA in the leaves of DD. The molecular weight (MW) of REE-DNA band was about 22 kb in agarose gel electrophoresis.     

活化分析

本文是《分析试验室》定期评述中“活化分析”的第6篇文章,它对我国活化分析领域在2003年6月-2005年12月的工作进展作了较全面的评述。内容包括活化分析方法学及其在生命科学、环境科学、地学和考古、国家安全等领域的应用,并展望了活化分析的发展趋势。     

α-甲基联苯酯类液晶的合成与性质

铁电液晶;相态行为;甲基位阻效应;α-甲基联苯酯类液晶的合成与性质     

Harmonic balance method with alternating frequency/time domain technique for nonlinear dynamical system with fractional exponential

Comparisons of the common methods for obtaining the periodic responses show that the harmonic balance method with alternating frequency/time （HB-AFT） do- main technique has some advantages in dealing with nonlinear problems of fractional exponential models. By the HB-AFT method, a rigid rotor supported by ball bearings with nonlinearity of Hertz contact and ball passage vibrations is considered. With the aid of the Floquet theory, the movement characteristics of interval stability are deeply studied. Besides, a simple strategy to determine the monodromy matrix is proposed for the stability analysis.     

轴上 SCN~-配位的含吡啶基十四元六氮大环配体 Co(Ⅱ)配合物的合成及性能的研究

以2,6-二乙酰吡啶和肼模板缩合制得新的轴上SCN~-配位十四元六氮大环配体(L)的 Co(Ⅱ)配合物[CoL(SCN)_2]·5H_2O.经红外光谱、电子光谱、电导、热分析和元素分析等推定为六配位的畸变八面体构型.配合物的磁矩测定值(3.86 BM)比理论值(5.20 BM)偏低,本文讨论了偏低的原因以及轴配位场强度与中心离子 Co(Ⅱ)高低自旋态的关系.还从电子光谱数据用配位场方法评价出D_q,B,β等数值和谱带的位置,理论值与实验值相当吻合.     

酚氧桥联的铜（Ⅰ）—钒（Ⅴ）双核配合物的合成

近年人们对研究桥联多核配合物的兴趣日益增加,已发现许多金属酶的活性部位均为多核配合物和生物体中许多重要的电子转移过程,也涉及到多核桥联结构。基于含酰胺基配体的生物性能,我们用N,N′-乙二水杨酰胶合铜(II)酸根([Cu(samen)]~(2-))作为阴离子双齿配体合成了一系列双核配合物,[Cu(samen)M(L)_x](M=Cu,x=1;M=Ni,Mn,     

计算非立方配位场中d轨道分裂能的简易图解法

以往,非立方场的理论计算多需采用复杂的数学处理,本文拟推荐一种简易的图解法。一、图解法的基本假设     

土壤-植物体系稀土元素的分异现象

用仪器中子活化分析测定了从同一地点采集的9种不同植物根和叶中8个稀土元素（La,Ce,Nd,Sm,Eu,Tb,Yb和Lu)的含量，研究了稀土元素在植物根、叶及相应母土中的分布特征。结果表明，同一植物的根、叶和母土中稀土分布模式均有较大差异。生长在同一地点不同植物根中稀土分布模式非常相似，而叶中分布规模差别较明显。说明根对单一稀土元素的吸收主要取决于这个元素在土壤中有效态的含量，而在稀土从根到叶的运输和积累过程中出现的分异则由植物自身的结构特征决定。     

LaCl3对轮藻光合色素含量及抗氧化酶活性的影响

研究了LaCl3对轮藻光合色素含量及抗氧化酶活性的影响,La3+浓度分别为0,0.2,1.0和5.0 μmol·L-1.结果表明0.2和5.0 μmol·L-1La3+处理降低了轮藻叶绿素b的含量,5.0 μmol·L-1 La3+处理降低了叶绿素a+b的含量;类胡萝卜素含量在1.0 μmol·L-1 La3+处理组显著高于对照.随着La处理浓度的提高超氧化物歧化酶的活性逐渐升高,处理组谷胱苷肽过氧化物酶活性均显著高于对照,且在1.0 μmol·L-1La处理组达到最大值,0.2和5.0 μmol·L-1 La3+处理将抑制过氧化氢酶活性,其变化规律与叶绿素b相似.实验浓度的La3+处理可能引起了轮藻植株的氧化损伤,作为应激反应,GSH-Px酶活性及类胡萝卜素含量的升高在一定程度上缓解了氧化损伤.     

以氯醌酸二价阴离子为桥联配体的Fe(Ⅲ)-Fe(Ⅲ)和Mn(Ⅱ)-Mn(Ⅱ)双核配合物的合成与磁性

Two new binuclear Fe(Ⅲ)-Fe(Ⅲ) and Mn(Ⅱ)-Mn(Ⅱ) complexes containing the dianions of chloranilic acids (CA) which act as bridging ligand in the complexes, have been synthesized namely [Fe₂(phen)₄(u-CA)](ClO₄)₄·2H₂O and [Mn₂(phen)₄(u-CA)](ClO₄)₂·3H₂O (phen = O-phenanthroline; CA = dianions of chloranilic acids). They have been characterized by elemental analyses, IR, electronic spectra, susceptibility and variable-temperature magnetic susceptibility. The results indicate that there is a antiferromagnetic interaction between metal ions in the complexes at low temperature. The observed data were well fitted to those from a Heisenberg model. The obtained parameters: J= -2.02cm^-1, g = 2.25 for Fe(Ⅲ)-Fe(Ⅲ) complex; J=-5.45cm^-1, g = 2.01 for Mn(Ⅱ)-Mn(Ⅱ) complex.