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61.
本文研究了广义Ramanujan-Nagell方程的正整数解,利用初等方法,得到了它的所有偶数解,从而部分地解决了该方程的求解问题. 相似文献
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本文采用过硫酸盐氧化树样中的总氮为硝态氮、总磷为磷酸盐,用分光光度法测定总氮量和总磷量,测得结果表明,本法所得精密度和准确度是比较好的,本方法能批量处理样品;省时、省电、省试剂、环境污染少。本法适用于树木中总氮总磷的测量。 相似文献
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We study the classical motion of an atom in the vicinity of an infinite straight wire which carries an oscillating uniform charge. This system has been proposed as a mechanism for trapping cold neutral atoms. The parameters of the problem are the magnitude Q and frequency of oscillation of the charge, the mass M and polarizability of the atom, and the angular momentum L of the atom about the wire. For 0 and 2MQ
2 greater than, but close to, L
2, we prove that the atom's radial motion is periodic (with period 2/), and that the atom moves in a helical path around the wire. For 2MQ
2 L
2 we prove that the atom must either collide with the wire or else escape to infinity in the radial direction. 相似文献
66.
[Cu(L-Ⅱe)(Phen)(H2O)(ClO4)]的合成、结构及稳定性研究 总被引:3,自引:0,他引:3
合成了三元混配配合物[Cu(L-Ile)(Phen)(H_2O)(ClO_4)](L-Ile=L=异亮氨酸,phen=1,10-邻菲咯啉),通过红外光谱、紫外-可见光谱、摩尔电导率、X射线单晶结构分析,对配合物进行了表征。该晶体属单斜晶系,P2_1空间群,晶胞参数:a=1.1704(5)nm,b=0.8090(5)nm,c=2.1822(5)nm,β=98.061(5)°,Z=2,D_x=1.60Mg·m~(-3),R_1=0.0462,wR_2=0.1225。每个配合物分子中Cu(Ⅱ)离子与一个L-Ile(N,O)配体、一个Phen(N,N)配体、一个H_2O(O)配体及一个Cl_O~-(O)形成六配位的畸变八面体构型。本文还用电位滴定法测定了配合物的稳定常数,结果表明,配合物具有高的稳定性。 相似文献
67.
Intramolecular stacking interaction in mixed-ligand complexes containing ATP4- and aromatic N-heterocyclic ligands 总被引:1,自引:0,他引:1
The stability constants of the binary ML2+ and ternary M(ATP)L2- complexes,where L=Iq (isoquinoline) or BIm (benzimidazole) and M=Zn2+ or Cd2+,have been determined by poten-tiometric pH titration in aqueous solution at I=0.1 mol/L (NaClO4),T=25℃.The stability of the ternary complexes characterized by corresponding to the equilibrium M(ATP)2-+ML2+=M(ATP)L2-+M2+ is higher than what would be expected on statistical grounds.The increase may be related to the stacking interaction between the aromatic ring of the ligands L and the purine moiety of ATP4- 1H NMR studies of Zn2+/ATP4-/L confirm the presence of stacking in the ternary complexes.It is concluded that the strength of the intramolecular stacking interaction is dependent on the structure of the aromatic ring of the ligand L and the formation of a metal ion bridge.Possible implications are discussed briefly. 相似文献
68.
The Interaction of three complexes [Cu(phen)(Gly)(H2O)]·ClO4·2.5H2O (1), [Cu(phen)(L-Val)(H2O)]·ClO4 (2) and [Cu(phen)(L-Ile)(H2O)]·ClO4 (3) (phen=1,10-phenanthroline, Gly=glycinate, L-Val=L-valinate, L-Ile=L-isoleucinate) with DNA have been investigated by electronic absorption spectroscopy, ethidium bromide(EB) fluorescence spectroscopy, viscosity and gel electrophoresis measurements. The intensity of maximal absorption peaks from absorption spectra are weakened with dropping DNA into the complexes. The emission intensity of EB-DNA systems in fluorescence spectroscopy have descended 50%, when the data of CCu / CDNA is 30~40. Moreover, the viscosity of DNA increase and then decrease with the increasing of complexes. All of the results indicate that the interaction of complexes with DNA are partial intercalation, and the result of agarose gel electrophoresis show that the complexes can cleave pBR322 DNA in the present of H2O2 / vitamin C. 相似文献
69.
Ternary complex [Cu(L-Ile)(TATP)(H2O)](ClO4)] was synthesized and characterized by molar conductivity, rotational analysis, spectroscopic (IR and UV-Vis) and X-ray diffraction methods, where L-Ile=L-Isoleucine, and TATP=1,4,8,9-tetraazatriphenylene. The complex crystallizes in triclinic space group P1 with two molecules in a unit cell of dimensions a=8.240 3(9) nm, b=11.914 9(13) nm, c=13.436 0(15) nm, α=109.136(2)°, β=101.101(2)°, γ=106.302(2)°. V=1.209 2(5) nm3, Z=2, Dc=1.589 Mg·m-3, μ=1.132 mm-1,R1=0.036 9, wR2=0.098 0. The crystal contains two independent [Cu(L-Ile)(TATP)(H2O)]+ complexes for Cu1 and Cu2, respectively, having essentially the same distorted square-pyramidal structure, where each Cu(Ⅱ) ion is coordinated with two nitrogen atoms of TATP and the amino nitrogen atom and one carboxylate oxygen atom of L-Ile in the equatorial positions and one water oxygen atom at an axial position. Furthermore, the primary studies on the interaction between the complex and calf thymus DNA were also performed by electronic absorption spectroscopy and viscosity methods. CCDC: 244231. 相似文献
70.