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71.
Two novel oxamidato-bridged Mn[Cu(PMoxd)]3(ClO4)2 (1) Ni[Cu(PMoxd)]3(ClO4)2 (2) tetranuclear complexes were prepared and characterized by i.r., e.p.r., electronic spectra, cyclic voltammograms, and magnetic properties. The magnetic analysis was carried out by means of the theoretical expression of the magnetic susceptibility deduced from the spin Hamiltonian H=−2JSM(SCu1+ SCu2 + SCu3) (M=Mn, Ni), leading to J=−20.4 cm−1; −121.1 cm−1 for complexes (1) and (2) respectively. Magnetic measurements indicate that the overall magnetic behavior of the tetranuclear species are antiferromagnetic.  相似文献   
72.
N-Phosphoryl peptide libraries were constructed by transformation from homo-oligopeptide libraries, which was synthesized by self-assembly of amino acids with the assistance of phosphorus oxychloride. Electrospray ionization mass spectrometry (ESI-MS) was used to monitor the reaction.  相似文献   
73.
合成了一个新配合物[Mn(napn)(CH3OH)2]ClO4 (C26H26 Cl N2O8Mn,Mr = 584.88,H2napn = 双a-萘酚醛缩乙二胺),并测定了其晶体结构。晶体属于三斜晶系,空间群P ,a = 7.813(1),b = 13.025(2),c = 14.089(2) ? = 64.89(3), = 83.98(3), = 78.11(3)海琕 = 1270.16 ?,Z = 2, Dc = 1.529 g/cm3, F(000) = 604, R = 0.0837, wR = 0.1636。锰(Ⅲ)离子的配位构型为拉长的八面体。Schiff碱配体napn2-中的N2O2在赤道平面与锰(Ⅲ)形成四配位,2个CH3OH中的O原子分别在赤道平面两侧轴向位置与锰(Ⅲ)配位。由于Jahn-Teller效应,轴向上的MnO平均键长为2.52 拧A硗猓О写嬖诜肿幽诤头肿蛹淝饧?  相似文献   
74.
研究了酵母核糖核酸(yRNA)在碳纳米管(MWNT)修饰电极上的电化学行为,优化了测定参数,在此基础上建立了一种直接测定yRNA的电分析测试方法。yRNA在碳纳米管修饰电极上于磷酸盐缓冲溶液中在0.758V处产生不可逆的氧化电流峰,峰电流与yRNA的质量浓度在1~10mg/mL之间有良好的线性关系,线性回归方程为:Iρ=0.0813ρ+0.1807,相关系数r为0.9980,检出限为0.6mg/mL。  相似文献   
75.
Assembly of [Ag(CN)2]^- units with M(Ⅱ)-diamine complex cations [Cu(LN-N)2]^2+, where LN-N represents L2-diaminopropane (pn) and ethylenediamine (en), afforded two complexes, [Cu(pn)2][Ag2(CN)4] (1) and [Cu(en)2][Ag3(CN)5] (2), which were characterized by elemental analysis, IR, UV-Vis and ESR spectra. Single crystal X-ray analyses show that these complexes have 2D and 3D architectures through silver-silver interactions and other weak interactions. The luminescence behaviors of the two complexes were also studied by means of emission spectra.  相似文献   
76.
Two compounds, [Co(bpy)2(NiL)](ClO4)2 (1)and {[Co(phen)3](NiL)}(ClO4)2 (2), have been synthesized: (H2L=2,3-dioxo-5,6,14,15-dibenzo-1,4,8,12-tetraazacylotetradeca-7,12-diene, bpy=2,2-bypyridine and phen = 1,10-phenanthroline). Compound (1) contains a discrete binuclear [Co(bpy)2(NiL)]2+ cation, while compound (2) is composed of [Co(phen)3]2+ cations and NiL neutral fragments. The magnetic properties of compound (1) have been dealt with by isotropic one-ion approximation of the CoII ion with a spin--orbit coupling in an Oh symmetry environment. The electronic spectra of these two compounds have also been discussed.  相似文献   
77.
费曼路径积分和霍金蒸发   总被引:2,自引:0,他引:2       下载免费PDF全文
刘辽 《物理学报》1982,31(4):519-524
在本文中,我们采用路径积分方法,证明了我们在不久前提出来的一个猜想,即与具体的时空度规形式无关,任一具有未来视界的静态和稳态时空,都存在霍金蒸发。 关键词:  相似文献   
78.
High molecular weight copoly(ether ketone)s (PEK) based on 4-(4-hydroxyphenyl)-1-phthalazinone (DHPZ)/4,4′-thiobisphenol (TBP)/4,4′-diflourodiphenylketone (DFK) were prepared by nucleophilic substitution polycondensation. The copolymers were characterized by FT- and ^1H-NMR. Thermal properties and solubility of copolymers were studied.  相似文献   
79.
A novel one-dimensional manganese(Ⅱ) complex containing nitronyl nitroxide radical [Mn2(IM2-py)2(Ac)2((μ1.1-N3)(μ1,3-N3) . EtOH]n was synthesized and characterized structurally and magnetically. It crystallizes in the monoclinic space group p21/n. Each Mn(Ⅱ) ion is six-coordinated in a distorted octahedral environment. The two N atoms of the nitronyl nitroxide radical and the two O atoms of acetate ligands are in the equatorial plane, whereas the two different azido bridging ligands are in trans axial position. Mn(Ⅱ) ions are linked by nitrogen atom of μ1,1-azido and oxygen atoms of two carboxy groups to form a Mn-Mn unit. Mn-Mn units are linked by azido ligands through u1,3 bridging style to form a one-dimensional chain. The compound is connected by the coordination bonds,π-π interactions and hydrogen bonds as a three-dimensional structure. Magnetic susceptibility data support that there are stronger antiferromagnetic interactions between the radical and Mn(Ⅱ) ion, weak antiferromagnetic inter  相似文献   
80.
Four new heterotrinuclear complexes have been synthesized and characterized, namely {[Ni(L)2]2[Cu(opba)]}(ClO4)2, where opba denotes o-phenylenebis(oxamato) and L stands for 1,10-phenanthroline(phen) (1), 5-nitro-l,10-phenanthroline(NO2-phen) (2), 2,2′-bipyridyl(bpy) (S) and 4,4′-dimethyl-2,2′-bipyridyl(Me2bpy) (4). The temperature dependence of the magnetic susceptibility of {[Ni(phen)2]2[Cu(opba)]}(ClO4)23H2O has been studied in the 4–300 K range, giving the exchange integral J—109 cm?1. The HMT vs. T plot exhibits a minimum at about 100 K, characteristic of this kind of coupled polymetallic complex with an irregular spin-state structure.  相似文献   
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