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1.
Two new mixed-ligands lanthanide coordination polymers, [Ln(Ac)(ip)(H2O)2]·0.5H2O (Ln=La (1); Ln=Eu (2); Ac=acetate; ip=isophthalate) have been synthesized under hydrothermal condition. Single-crystal X-ray analyses show that complexes 1 and 2 are three-dimensional structure in which lanthanide ions are bridged by monocarboxylate ligand, acetate or dicarboxylate ligand, isophthalate. And the central lanthanide ions, La3+ and Eu3+, are both nine-coordinate with oxygen atoms. The thermogravimetric analysis was carried out to examine the thermal stability of the title complexes. And the photoluminescence property of complex 2 was also investigated. 相似文献
2.
A novel assay of γ-globulin (γ-IgG) with a sensitivity at the nanogram level is proposed based on the measurement of enhanced resonance light-scattering (RLS) signals resulting from the interaction of functionalized nano-HgS with γ-globulin. At pH 5.03, the RLS signals of functionalized nano-HgS were greatly enhanced by γ-globulin in the region of 200-700 nm characterized by the peak around 362 nm. Linear relationship can be established between the enhanced RLS intensity and γ-globulin concentration in the range of 10-140 ng ml−1. The limit of detection is 2.71 ng ml−1. Based on this, a new direct quantitative determination method for γ-globulin in blood serum samples without separation of human serum albumin (HSA) is established. The contents of γ-IgG in blood serum samples were determined with recovery of 95.7-102.5% and R.S.D. of 1.6-2.4%. This method is proved to be very sensitive, rapid, simple and tolerance of most interfering substances. 相似文献
3.
Wen-Bin Lee Shin-Chu Suen Ting-Ting Jong Fung-E Hong Jyh-Horung Chen
Hann-Jenn Lin
Lian-Pin Hwang
《Journal of organometallic chemistry》1993,450(1-2):63-66meso-Tetraphenylporphyrinatothallium(III) cyanide, Tl(tpp)(CN), was previously assumed to be monomeric and has been confirmed by X-ray analysis to exist as two independent molecules in one asymmetric unit. This unit displays two square-pyramidal coordination geometries for the thallium atoms with the cyano ligand coordinated to both Tl atoms. It crystallizes in the triclinic space group P
, with a 10.003(3), b 16.231(7), c 21.277(8) Å, 89.98(3), β 90.57(3), γ 90.31(3)°' and z = 4. The structure was solved by direct methods. A total of 7995 unique reflections having I > 3σ(I) was measured with an automated diffractometer and used to refine the crystal structure to a conventional R factor of 6.05 %. The thallium-cyanide distances are 2.140(14) Å (for thallium(I)) and 2.277(14) Å (for thallium(2)) respectively, with thallium(1) situated 0.908 Å above the porphyrin ring and thallium(2) located 1.027 Å below the ring. IR and NMR spectroscopy p rovide complementary methods for investigation of the CN ligand. The characteristic band observed at 2160 cm−1 in the FTIR spectrum is assigned to the CN stretching in the Tl(tpp)(CN) complex. The 13C resonance of axial cyano ligand is observed with a pulse delay of 3.5 s at 24°C at 139.2 ppm (with 1J(205Tl-13C) 5394 and 1J(203Tl-13C) 5344 Hz). This observation disagrees with the conclusion, drawn from previous work, in that an exchange process involving the apical ligand explains the invisibility due to line broadening at 35°C of the 13C signal. 相似文献
4.
5.
The relation between the total variation of classical field theory and the multisymplectic structure is shown. Then the multisymplectic structure and the corresponding multisymplectic conservation of the coupled nonlinear Schrodinger system are obtained directly from the variational principle. 相似文献
6.
Oscillation of coercivity between positive and negative in MnxGe1-x:H ferromagnetic semiconductor films 下载免费PDF全文
Amorphous MnxGe1-x :H ferromagnetic semiconductor films prepared in mixed Ar with 20% H2 by magnetron cosputtering show global ferromagnetism with positive coercivity at low temperatures. With increasing temperature, the coercivity of MnxGe1-x :H films first changes from positive to negative, and then back to positive again, which was not found in the corresponding MnxGe1-x and other ferromagnetic semiconductors before. For Mn0.4Ge0.6 :H film, the inverted Hall loop is also observed at 30 K, which is consistent with the negative coercivity. The negative coercivity is explained by the antiferromagnetic exchange coupling between the H-rich ferromagnetic regions separated by the H-poor non-ferromagnetic spacers. Hydrogenation is a useful method to tune the magnetic properties of MnxGe1-x films for the application in spintronics. 相似文献
7.
This paper analytically investigates the interaction of light
filaments generated by a femtosecond laser beam in air. It obtains the
Hamiltonian of a total laser field and interaction force between two
filaments with different phase shifts and crossing angles. The
property of the interaction force, which leads the attraction or
repulsion of filaments, is basically dependent on the phase shift
between filaments. The crossing angle between two filaments can only
determine the magnitude of the interaction force, but does not
change the property of the force. 相似文献
8.
通过水热法,在黑磷(BP)纳米片表面生长FeOOH纳米材料,制备出FeOOH/BP纳米复合材料。作为电化学析氧反应(OER)催化剂,该复合材料在20 mA·cm-2时的过电位仅为191 mV,Tafel斜率为49.9 mV dec-1;在循环1 000圈后,过电位仅仅增加了3 mV,且循环过程中元素价态不变,表现出优秀的稳定性。纳米FeOOH负载于BP表面,客观上能隔断氧气对BP的氧化,保护BP的载流子传导性能。同时,生长的FeOOH颗粒尺度小,结晶性弱,这有利于丰富其活性位点,增大活性面积。 相似文献
9.
Wen-Xing Yang Ai-Xi Chen Ting-Ting Zha Yanfeng Bai Ray-Kuang Lee 《Central European Journal of Physics》2014,12(10):737-743
We demonstrate the generation of two-mode continuous-variable (CV) entanglement in a V-type three-level atom trapped in a doubly resonant cavity using a microwave field driving a hyperfine transition between two upper excited states. By numerically simulating the dynamics of this system, our results show that the CV entanglement with large mean number of photons can be generated even in presence of the atomic relaxation and cavity losses. More interestingly, it is found that the intensity and period of entanglement can be enhanced significantly with the increasing of the atomic relaxation due to the existence of the perfect spontaneously generated interference between two atomic decay channels. Moreover, we also show that the entanglement can be controlled efficiently by tuning the intensity of spontaneously generated interference and the detuning of the cavity field. 相似文献
10.
以3-硝基邻苯二甲酸和咪唑及2,2′-联吡啶为配体构筑了2种配合物[Zn2(npa)2(Im)4](1)和[Cd2(npa)2(2,2′-bipy)2(H2O)2]·2H2O(2)(npa2-=3-硝基邻苯二甲酸根,Im=咪唑,2,2′-bipy=2,2′-联吡啶)。用元素分析、红外光谱对其进行了表征,并用单晶X-射线衍射测定了配合物的晶体结构;测定了配合物1和2的热稳定性。2个配合物均为双核分子,具有M2C8O4十四元大环结构。配合物1的双核单元通过分子间氢键形成3D网络结构,配合物2的双核单元通过分子间氢键和π-π堆积形成2D层状结构。 相似文献