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51.
以金属Cu(Ⅱ),Ni(Ⅱ),Cd(Ⅱ)为中心离子,分别合成2-(2-吡啶基)苯并噻唑为配体的配合物,其中得到了以Cu(Ⅱ)为中心离子的晶体,并培养出了单晶.该配合物是五配位的三斜晶系,上述金属配合物都能与DNA结合,并能有效断裂DNA链,可以通过与癌症细胞的DNA发生解旋DNA的作用从而引起癌症细胞DNA的损伤,使癌细胞的DNA在复制和转录的过程中受到阻碍,从而阻止癌细胞的生长和分裂,并导致癌细胞的死亡.为其在药物开发和分子生物学中的应用提供了有价值的信息. 相似文献
52.
Xiangling Zhu 《Numerical Functional Analysis & Optimization》2013,34(7-8):881-893
The boundedness and compactness of the generalized weighted composition operator on weighted Bergman spaces are discussed. 相似文献
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54.
《Comptes Rendus Physique》2016,17(5):565-577
It is common for dispersion curves of damped periodic materials to be based on real frequencies as a function of complex wavenumbers or, conversely, real wavenumbers as a function of complex frequencies. The former condition corresponds to harmonic wave motion where a driving frequency is prescribed and where attenuation due to dissipation takes place only in space alongside spatial attenuation due to Bragg scattering. The latter condition, on the other hand, relates to free wave motion admitting attenuation due to energy loss only in time while spatial attenuation due to Bragg scattering also takes place. Here, we develop an algorithm for 1D systems that provides dispersion curves for damped free wave motion based on frequencies and wavenumbers that are permitted to be simultaneously complex. This represents a generalized application of Bloch's theorem and produces a dispersion band structure that fully describes all attenuation mechanisms, in space and in time. The algorithm is applied to a viscously damped mass-in-mass metamaterial exhibiting local resonance. A frequency-dependent effective mass for this damped infinite chain is also obtained. 相似文献
55.
56.
A. Lushchik M. Kirm I. Kudryavtseva C. H. Lushchik I. Martinson V. Nagirnyi 《辐射效应与固体损伤》2013,168(6-12):537-543
The processes of multiplication of electronic excitations (MEE), connected with the creation of secondary excitons or electron-hole (e-h) pairs by hot conduction electrons, are realized in wide-gap metal halides and oxides. In oxides, secondary e-h pairs can be also formed by 27-40 v eV photons due to L 1 VV Auger transitions (with the participation of 2s oxygen holes). The excitation spectra of luminescence and the creation spectra of electron F centres or hole V centres have been measured for Na 6 Al 6 Si 6 O 24 (NaI) 2x sodalites and MgO:Be, respectively, at 8-80 v K. A high local density of excitations has been revealed under MEE conditions in KBr and Br sodalites with self-trapping excitons and holes. 相似文献
57.
π-complemented algebras are defined as those (not necessarily associative or unital) algebras such that each annihilator ideal is complemented by other annihilator ideal. For a given semiprime algebra A, we discuss the π-complementation of the unitisation algebra A 1 of A. Moreover, if in addition the multiplication algebra ?(A) of A is also semiprime, we study the π-complementation in the algebras ?(A) and ??(A) (the multiplication ideal of A). In associative setting, we prove that A is π-complemented if and only if ??(A) is π-complemented, and that A 1 π-complemented if and only if ?(A) is π-complemented. 相似文献
58.
Agota Figula 《代数通讯》2013,41(1):444-468
We prove that each 3-dimensional connected topological loop L having a solvable Lie group of dimension ≤5 as the multiplication group of L is centrally nilpotent of class 2. Moreover, we classify the solvable non-nilpotent Lie groups G which are multiplication groups for 3-dimensional simply connected topological loops L and dim G ≤ 5. These groups are direct products of proper connected Lie groups and have dimension 5. We find also the inner mapping groups of L. 相似文献
59.
用水热合成和常温合成法分别制备了以锌离子和铜离子为主体、1,2,4-苯三甲酸和4,4’-联吡啶为配体的两种金属有机配合物材料,并考察了其对多环芳烃(PAHs)的吸附性能。用粉末衍射仪(XRD)、热重分析仪(TGA)、傅里叶红外光谱仪(FT-IR)、扫描电镜仪(SEM)和比表面积测试仪(BET)表征了材料的组成、形貌、热稳定性和吸附等性能。结果表明,两种配合物具有较好的热稳定性和吸附能力;PAHs在两种配合物材料上的吸附动力学均符合假二级动力学模型,吸附行为均符合Langmuir方程,且两种配合物对PAHs吸附量随着配合物用量的增加而增大。此外,两种配合物材料对10种PAHs均能有效富集吸附,且吸附具有选择性。通过对该金属有机配合物材料进一步优化有望作为色谱固定相使用。 相似文献
60.
Vladimir N. Makhov Cheslav Lushchik Marco Kirm Wei-Ping Zhang Jing-Tai Zhao 《Journal of luminescence》2009,129(12):1711-1714
Luminescence properties of Lu2O3:Eu3+ and Lu2O3:Tb3+ nanocrystalline powders with the particle size varying from 46 to 6 nm were studied under excitation by synchrotron radiation in the photon energy range (up to ∼22.5 eV) covering the region where the processes of multiplication of electronic excitation occur. It was found that the excitation spectra of Tb3+ emission from all Lu2O3:Tb3+ nanopowders have similar behavior, whereas the shape of the excitation spectra of Eu3+ emission from Lu2O3:Eu3+ nanopowders strongly depends on the particle size. The difference in the behavior of Lu2O3:Eu3+ and Lu2O3:Tb3+ nanophosphor systems was explained by different mechanisms of the energy transfer from the host to Eu3+ or Tb3+ ions (either the hole or electron recombination mechanism, respectively), which are differently influenced by losses of electronic excitations near the particle surface. 相似文献