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金属配合物中的水簇研究为研究宏观意义上的水以及与蛋白质分子有关的水分子提供了有效途径。本文合成了一个含有阴离子水簇的带状超分子配合物[Co(2,2-bipy)2(N3)2](N3)0.5Cl0.5·2H2O(1,2, 2-bipy=2, 2-联吡啶)。单晶结构解析表明,配合物属于三斜晶系,P-1空间群,晶胞参数为:a=0.822 54(7) nm,b=1.175 58(9) nm,c=1.237 06(10) nm,α=91.379 0(10)°,β=92.151 0(10)°,γ=108.119 0(10)°,V=1.135 27(16) nm3,由一个单核[Co(2,2-bipy)2(N3)2]+配合物阳离子、两个非配位水分子、0.5个游离的叠氮离子和0.5个氯离子组成,叠氮离子和氯离子位置无序,占有率各为50%。两个客体水分子通过强烈的分子间氢键作用形成了环状水四聚体,且与无序的N-3和Cl-通过氢键作用形成了一个[(H2O)4(N3)Cl]2- 阴离子水簇。此外,本文基于密度泛函理论(DFT)对配合物[Co(2,2-bipy)2(N3)2]+阳离子进行了量子化学计算,分析了其单点能和原子电荷,并计算了中心金属离子的氧化态,计算结果与实验相吻合。 相似文献
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采用高效液相色谱-串联质谱(LC-MS/MS)技术建立了医用口罩中全氟辛酸、全氟辛烷磺酸钾、全氟十一酸、全氟十二酸、全氟辛烷磺酸胺、全氟十三酸、全氟十四酸、N-乙基全氟辛烷磺酸胺8种全氟化合物的测定方法。样品以甲醇为溶剂,超声提取,采用C18(150 mm×2.1 mm, 5μm)色谱柱分离,流动相为甲醇和乙酸铵,梯度洗脱,多反应监测(MRM)模式进行分析检测,外标法定量。结果表明:8种全氟化合物的定量限(LOQ,以信噪比>10计)为0.50~1.58μg/kg,在0.5~10μg/L时标准曲线线性关系良好(r>0.9979),样品加标回收率为98.4%~102.3%,相对标准偏差为1.55%~7.44%。该方法前处理简单,回收率高,精密度好,适用于医用口罩中全氟化合物的检测。 相似文献
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By introducing a new tortoise coordinate transformation, we investigate the quantum thermal and non-thermal radiations of a non-stationary Kerr--Newman--de Sitter black hole. The accurate location and
radiate temperature of the event horizon as well as the maximum energy of the non-thermal radiation are derived. It is shown that the radiate temperature and the maximum energy are related to not only the evaporation rate, but also the shape of the event horizon, moreover the maximum energy depends on
the electromagnetic potential. Finally, we use the results to reduce the non-stationary Kerr--Newman black hole, the non-stationary Kerr black hole, the stationary Kerr--Newman--de Sitter black hole, and the static Schwarzshild black hole. 相似文献
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Recent research shows that Hawking radiation from black hole horizon can be treated as a quantum tunneling process, and fermions tunneling method can successfully recover Hawking temperature. In this tunneling framework, choosing a set of appropriate matrices γ^μ is an important technique for fermions tunneling method. In this paper, motivated by Kerner and Man's fermions tunneling method of 4 dimension black holes, we further improve the analysis to investigate Hawking tunneling radiation from a rotating charged black hole in 5-dimensional gauged supergravity by constructing a set of appropriate matrices γ^μ for general covariant Dirac equation. Finally, the expected Hawking temperature of the black hole is correctly recovered, which takes the same form as that obtained by other methods. This method is universal, and can also be directly extend to the other different-type 5-dimensional charged black holes. 相似文献
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Hawking radiation as tunnelling from arbitrarily dimensional Reissner-Nordstrom de Sitter black hole 下载免费PDF全文
This paper extends Parikh-Wilzcek's recent work, which treats the Hawking radiation as a semi-classical tunnelling process from the event horizon of four dimensional Schwarzshild and Reissner-Nordstrom black holes, to that of arbitrarily dimensional Reissner-Nordstrom de Sitter black hole. The result shows that the tunnelling rate is related to the change of Bekenstein-Hawking entropy and the factually radiant spectrum is no longer precisely thermal after taking the dynamical black hole background and energy conservation into account, but is consistent with the underlying unitary theory and then satisfies the first law of the black hole thermodynamics. Meanwhile, in Parikh-Wilzcek's framework, this paper points out that the information conservation is only suitable for the reversible process but in highly unstable evaporating black hole (irreversible process) the information loss is possible. 相似文献
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The Banerjee-Majhi's recent work shows that the Hawking radiation and entropy/area quantum of the black hole horizon (EH) can be well described in the tunneling picture. In this paper, we develop this idea to the case o a de Sitter tunneling from the cosmological horizon (CH), and obtain the Hawking emission spectrum and entropy/area spectroscopy from the CH of the purely de Sitter black hole as well as the Schwarzschild-de Sitter black hole. It i interestingly found that the area of the CH is quantized by A = 4l 2 pl , as was given by Hod for the area quantum of -the EH by considering the Heisenberg uncertainty principle and Schwinger-type emission process. Also, we conclude from our derivation that the entropy/area quantum of the CH is universal in the sense that it is independent of the black hole parameters. This realization implies that, (at least) at a semiclassical level, the de Sitter gravity shares the similar quantum behavior as the usual gravity without presence of a cosmological constant. 相似文献
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<正>The aim of this paper is to investigate the area spectrum of the three-dimensional Godel black hole by using two different methods.The result shows that the area spectrum of the black hole is△A = 8πl_p~2,which confirms the initial proposal of Bekenstein that the area spectrum is independent of black hole parameters and the spacing is 8πl_p~2. 相似文献