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Bulk samples with nominal composition Zn0.95Co0.05O and Zn0.92Co0.05Mn0.03O were fabricated by a solid-state reaction method at 600℃.X-ray diffraction experiment showed that the peaks of secondary phase Co3O4 with a cubic structure were visible in both samples,besides the main peaks of wurtzite structure as ZnO.Magnetization measurement indicated that doping Co alone can induce ferromag- netism in ZnO itself,while the introduction of Mn significantly enhances ferromagnetism.However, both samples showed different magnetic behavior at temperatures below 50 K.It was also noted that ferromagnetic coupling interaction was weakened due to the presence of antiferromagnetic Co3O4.  相似文献   
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Bueh  Cholaw  Shi  Ning  Ji  LiRen  Wei  Jie  Tao  ShiYan 《科学通报(英文版)》2008,53(4):610-623
In this paper, features for the evolution of the East Asia/Pacific (EAP) events and their association with high- and mid-latitude Rossby waves during the Meiyu period are analyzed on the medium-range time scale, it is shown that life cycles of the positive and negative EAP events cannot be simply regarded as "mirror" each other. In the upper troposphere, downward propagations of Rossby wave packets both over high- and mid-latitude regions of Eurasian continent and over the Asian jet region are responsible for generating basic patterns of high- and mid-latitude anomaly centers of the events. In this layer, Rossby wave packets also propagate from the mid-latitude anomaly center to the high-latitude one. In the middle and lower troposphere, the formation of the subtropical anomaly center of the event is mainly attributed to the anomalous convective activity in the tropical Pacific warm pool. The northward Rossby wave energy dispersion from this center is favorable to the enhancement and maintenance of the mid-latitude anomaly center in the same layer. Finally, it might be hypothesized that typical features of the positive and negative EAP events in their mature phase result from the interaction between (or phase-locking of) respective anomalous circulations induced both by quasi-zonal Rossby wave packets embedded in upper troposphere westerly and by quasi-meridional Rossby wave packets in the background flow of the East Asian summer monsoon in the middle and lower troposphere.  相似文献   
3.

For a sample of 411 type II QSOs with redshifts less then 0.3, we use the Balmer decrements to do the reddening correction of the [O III] luminosities and then derive the intrinsic [O III] luminosity function. We find that the host reddening correction of the [O III] 5007 luminosity for type II QSOs cannot be neglected. The median Balmer decrement of Hα/Hβ=4.0 corresponds to an extinction of 0.94 mag for the [O III] 5007 line, which is consistent with the result derived from the median Hβ/Hγ. Comparing the intrinsic luminosity function of type II QSOs with that of type I QSOs, we find that the upper limit of the type II QSO’s fraction in the total QSOs is 80% for type II QSOs with z < 0.3 and 8.6⩽log (L [O III]/L )⩽9.4.

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The in-plane thermal conductivity of the iron-based superconductor Ca10(Pt_(4-δ)As_8)((Fe_(1-x)Pt_x)_2As_2)_5 single crystal("10-4-8", T c= 22 K) was measured down to 80 m K. In a zero field, the residual linear term κ_0/T is negligible, suggesting the nodeless superconducting gaps in this multiband compound. In the magnetic fields, κ_0/T increases rapidly, which mimics the multiband superconductor Nb Se_2 and Lu Ni_2B_2 C with highly anisotropic gap. Such a field dependence of κ_0/T is an evidence for the multiple superconducting gaps with quite different magnitudes or highly anisotropic gap. Compared with the London penetration depth results of the Ca10(Pt_(4-δ)As_8)((Fe_(1-x)Pt_x)_2As_2)_5("10-3-8") compound, the 10-4-8 and 10-3-8 compounds may have a similar superconducting gap structure.  相似文献   
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Fifteen novel 2‐alkylamino‐3‐aryl‐8‐cyano‐5‐methyl‐7‐(methylthio)‐pyrido[4,3‐d]pyrimidin‐4(3H)‐ones 6a , 6b , 6c , 6d , 6e , 6f , 6g , 6h , 6i , 6j , 6k , 6l , 6m , 6n , 6o were designed and have been successfully synthesized via tandem aza‐Wittig and annulation reactions with the corresponding iminophosphoranes 4 , aryl isocyanate, and amines in good yields. Their structures were clearly verified by IR spectroscopy, 1H‐NMR spectroscopy, EI‐MS, and elemental analysis, and in the case of compound 6i , further analyzed by single‐crystal X‐ray diffraction. The preliminary results of an in vivo bioassay showed that some compounds display moderate antifungal activity.  相似文献   
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