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41.
High-spin states in 161Er have been studied experimentally via the 150Nd(16O, 5n) reaction at a beam energy of 86 MeV. Three rotational bands built on the 5/2+[642], 3/2-[521], and 11/2-[505] configurations have been extended up to high-spin states, and particularly, the α = -1/2 branch of the ground state 3/2-[521] band has been revised significantly. It is found that signature inversion occurs in the 3/2-[521] band after the band crossing in 161Er. The systematics of the signature inversion associated wit...  相似文献   
42.
The third-order ghost imaging with the second-order intensity correlation is theoretically and experimentally demonstrated.The resolution and visibility of the reconstructed image are discussed,and the relationship between resolution and visibility is analyzed.The theoretical results show that a tradeoff exists between the visibility and resolution of the reconstructed image;the better the image resolution,the worse the image visibility.Numerical simulations are carried out to verify this theory,and a ghost...  相似文献   
43.
Nanorod-like Ce 0.7 Zr 0.3 O 2 solid solutions were synthesized by a sodium dodecyl sulfate-assisted precipi- tation method. The samples were characterized by means of scanning electron microscopy, transmission electron microscopy, X-ray diffraction, Fourier transform infrared spectroscopy, and specific surface area measurement. Typical Ce 0.7 Zr 0.3 O 2 nanorods were 40 nm in average diameter and 450 nm in length, with specific surface area and oxygen storage capacity of 194 m 2 /g and 374 mol/g, respectiv...  相似文献   
44.
In this paper, we consider a degenerate steady-state drift-diffusion model for semiconductors. The pressure function used in this paper is ()(s) = s~α(α > 1). We present existence results for general nonlinear diffhsivities for the degenerate Dirichlet-Neumann mixed boundary value problem.  相似文献   
45.
Ten coumarin derivatives containing(E)-methyl 2-(methoxyimino)-2-phenylacetate were synthesized and bioassayed.The compounds were identified by IR,~1H NMR and elemental analyses.The test results indicated that compound 5j(R~1 is methyl and R~2 is n-C_6H_(13)) was the optimal structure in this paper with good fungicidal activity against CDM(85%) at 6.25 mg/L concentration.  相似文献   
46.
ZnO particles about 200 nm were prepared through a facile hydrothermal method.Compared with single ozonation,the degradation efficiency of phenol increased about 23.7%and the degradation efficiency of intermediates improved about four times in the presence of ZnO at 298 K.In addition,the catalyst had good stability in the ozonation process.The influence of temperature was investigated and it was found that the better catalysis efficiency could be obtained at lower temperature.  相似文献   
47.
Soluble and ordered ladder like polyphenylsilsesquioxane was synthesized by a two-step sol-gel method including hydrolysis and polycondensation. The procedure was monitored by Fourier transform infrared spectroscopy and the presence of the ladder like structure was confirmed by X-ray techniques. 29Si NMR analysis shows a very narrow half peak width(δ<4) at δ -78.866 of the main chain unit C6H5SiO3/2 of polyphenylsilsesquioxane, indicating that the polyphenylsilsesquioxane has ordered ladder like structures ...  相似文献   
48.
Two new compounds with microporous Co3[MnMo9O32].15H2O(1) and Cu3[MnMo9O32].15H2O(2) have been synthesized,and characterized by IR,element analysis,TG and single-crystal X-ray analysis.The structure analyses reveal that compounds 1 and 2 are isostructural.In crystal,the Waugh-type polyoxoanions [MnMo9O32]6-are connected by Co2+ or Cu2+ cations to a 3D open-framework,which possesses channels along the [1 2 2] direction of approximately 8.27 × 11.97 .The photocatalytic performances of compounds 1 and 2 for p...  相似文献   
49.
Rigid trigonal tris(3-pyridylduryl)borane L was synthesized through four steps in good overall yield from readily available 1,2,4,5-tetramethylbenzene and was used to construct two porous cadmium(II) complexes Cd(L)X2.G(X = Cl,Br;G = guset molecules),1(Cd(L)Cl2.EtOH.iPrOH.3H2O) and 2(Cd(L)Br2.MeOH.C7H8.3H2O),under mild reaction conditions.1 and 2 are isostructural and featured with 3D porous metal-organoboron framewoks with rtl topology,in which L acts as a 3-connected node while a dicadmium motif serves as...  相似文献   
50.
Recent precise, elastic numerical solutions to a surface flaw in a plate under remote tension and bending have been compared to arrive at a ‘best estimate’ of the stress-intensity-factor variation along the flaw border. The geometry of the semielliptical surface flaw examined had a depth to length ratio of 0.25 (a/2c=0.25) and 25- and 75-percent relative crack depths (a/t=0.25, 0.75). The analysis methods used to determine the solutions included: Schwarz alternating technique, finite-element method and boundary-integral-equation method. The derived best-estimate curve for the stress-intensity factor is believed within 3 percent of the actual value along the crack front. The best-estimate curve compared well with scarce experimental data (±10 percent). The difference between the best-estimate curve and experiment is thought largely due to differences in geometry and Poisson's ratio.  相似文献   
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