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71.
72.
以FeCl3为铁源, 葡萄糖为碳源, 钛酸四丁酯为钛源, 采用水热法制备了磁载光催化剂Fe3O4/C/TiO2, 用TEM、EDX、VSM、XRD和IR对Fe3O4/C/TiO2的粒径、形貌和物相等进行了表征。研究了该催化剂对三氯苯酚的降解性能, 探讨了其重复使用的可能性, 用荧光光谱法推测了可能的反应机理。结果表明该材料结合了光催化与可再生的优点, 1 g·L-1 Fe3O4/C/TiO2在18 W紫外灯下, 50 min内可将三氯苯酚降解97.9%以上, 6次循环使用后降解率仍保持在95.1%, 降解过程中有羟基自由基生成。  相似文献   
73.
We first convert the angular Teukolsky equation under the special condition of τ ≠ 0, s ≠ 0, m=0 into a confluent Heun differential equation (CHDE) by taking different function transformation and variable substitution. And then according to the characteristics of both CHDE and its analytical solution expressed by a confluent Heun function (CHF), we find two linearly dependent solutions corresponding to the same eigenstate, from which we obtain a precise energy spectrum equation by constructing a Wronskian determinant. After that, we are able to localize the positions of the eigenvalues on the real axis or on the complex plane when τ is a real number, a pure imaginary number, and a complex number, respectively and we notice that the relation between the quantum number l and the spin weight quantum number s satisfies the relation l=∣s∣+ n, n=0, 1, 2···. The exact eigenvalues and the corresponding normalized eigenfunctions given by the CHF are obtained with the aid of Maple. The features of the angular probability distribution (APD) and the linearly dependent characteristics of two eigenfunctions corresponding to the same eigenstate are discussed. We find that for a real number τ, the eigenvalue is a real number and the eigenfunction is a real function, and the eigenfunction system is an orthogonal complete system, and the APD is asymmetric in the northern and southern hemispheres. For a pure imaginary number τ, the eigenvalue is still a real number and the eigenfunction is a complex function, but the APD is symmetric in the northern and southern hemispheres. When τ is a complex number, the eigenvalue is a complex number, the eigenfunction is still a complex function, and the APD in the northern and southern hemispheres is also asymmetric. Finally, an approximate expression of complex eigenvalues is obtained when n is greater than ∣s∣.  相似文献   
74.
The energy spectrum of the Manning-Rosen potential including centrifugal term in higher dimensions is presented by exact quantization rule approach. The result is compared with that by proper quantization rule method. It is found that the latter is better than that of the exact quantization rule. We find that the interdimensional degeneracy exists for the states in different dimensions. For the special case D = 3, the results agree well with those obtained by other methods.  相似文献   
75.
Two new steroids, named 4α,22-dimethyl-Cholest-22-en-3β-ol (1) and 4α-methyl-Cholest-7,22-dien-3β-ol (2), along with two known steroids, were isolated from the soft coral Sinularia brassica. The structures of the new compounds were determined on the basis of extensive spectroscopic data (MS, (1)H and (13)C NMR, (1)H-(1)H COSY, (13)C-(1)H COSY, HMBC and NOESY) analysis.  相似文献   
76.
In this work, we study the position and momentum information entropies of multiple quantum well systems in fractional Schrödinger equations, which, to the best of our knowledge, have not so far been studied. Through a confining potential, their shape and number of wells (NOW) can be controlled by using a few tuning parameters; we present some interesting quantum effects that only appear in the fractional Schrödinger equation systems. One of the parameters denoted by the Ld can affect the position and momentum probability densities if the system is fractional (1 < α < 2). We find that the position (momentum) probability density tends to be more severely localized (delocalized) in more fractional systems (ie, in smaller values of α). Affecting the Ld on the position and momentum probability densities is a quantum effect that only appears in the fractional Schrödinger equations. Finally, we show that the Beckner Bialynicki-Birula-Mycieslki (BBM) inequality in the fractional Schrödinger equation is still satisfied by changing the confining potential amplitude Vconf, the NOW, the fractional parameter α, and the confining potential parameter Ld .  相似文献   
77.
The irreducible bases in the icosahedral groupspace are calculated explicitly by reducing the regularrepresentation. The symmetry-adapted bases of the systemwith I or I h symmetry can becalculated easily and generally by applying those irreduciblebases to wavefunctions of the system, if they are notvanishing. As examples, the submatrices of the HuckelHamiltonians for carbon-60 and carbon-240 arerecalculated by the irreducible bases.  相似文献   
78.
The existing theory of decoy-state quantum cryptography assumes that the dark count rate is a constant, but in practice there exists fluctuation. We develop a new scheme of the decoy state, achieve a more practical key generation rate in the presence of fluctuation of the dark count rate, and compare the result with the result of the decoy-state without fluctuation. It is found that the key generation rate and maximal secure distance will be decreased under the influence of the fluctuation of the dark count rate.  相似文献   
79.
We apply the finite key analysis to the decoy state quantum key distribution scheme and obtain a practical key rate. By simulating an practical experiment setups and the Vacuum + Weak decoy state method, we show that both the key rate and maximal secure distance are reduced when the finite key analysis is considered.  相似文献   
80.
TMPTA红外激光光聚合的实时动力学研究   总被引:5,自引:0,他引:5  
采用实时FTIR研究了在红外激光照射下,阳离子菁染料-有机硼络合物1,3,3,1',3',3'-六甲基-11-氯-10,12-亚丙基吲哚三碳菁-正丁基三苯基硼引发的三羟甲基丙烷三丙烯酸酯(TMPTA)的光聚合反应动力学.研究发现,随激光功率的提高,单体的聚合速度与双键转化率均有显著提高.在临界浓度以下,引发剂的含量增加可以加快光聚合反应速率.样品厚度的增加明显降低双键转化率与聚合速度.计算结果表明,该体系的量子聚合效率为41.8mol/einstein.在17.0mW/cm2激光照射下TMPTA最高双键转化率可以达到80%.  相似文献   
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