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1.
International Journal of Theoretical Physics - Quantifying the quantumness of ensembles is a vital and practical task in quantum information theory. In this paper, we quantify the quantumness of...  相似文献   
2.

Uncertainty relation is a core issue in quantum mechanics and quantum information theory. We introduce modified generalized Wigner-Yanase-Dyson (MGWYD) skew information and modified weighted generalized Wigner-Yanase-Dyson (MWGWYD) skew information, and establish new uncertainty relations in terms of the MGWYD skew information and MWGWYD skew information.

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3.
For zeolite catalysts, the regulation of active site and pore structure plays an important role in the enhancement of their catalytic performance. In this work, a one-pot and organic template-free co-regulation route is proposed to straightforwardly synthesize basic mesoporous ZSM-5 zeolites with adjustable alkaline-earth metal species. The synthesis pathway combines two decisive strategies: 1) the seed-induced interface assembly growth method and 2) the acidic co-hydrolysis/condensation of aluminosilicate species and alkaline-earth metal (e.g., Mg, Ca, Sr, or Ba) sources. It is interesting that the mesoporous structure was self-evolved through particle-attached seed-interfacial crystallization without the assistance of any template. Meanwhile, the incorporation of alkaline-earth metals species is homogeneous and highly dispersed in the solid products during the whole crystallization process, and finally generate the superior basicity. Catalysis tests of the as-synthesized samples displayed their novel performance in the typical base reaction of Knoevenagel condensation, even for bulky substrates owing to the enhanced diffusion arising from the meso/microporous network. This finding opens new possibilities for facile, cost-effective, and environmentally friendly synthesis of mesoporous high-silica zeolites with tunable acid/base properties, and deepens our understanding of the particle-attached crystallization.  相似文献   
4.
5.
This study was to validate the feasibility of using a magnetic resonance imaging-guidewire (MRIG) for intravascular 3.0 T MR imaging of deep-seated arterial walls of large animals. The functionality of a 0.032-in. MRIG was evaluated and the signal-to-noise ratio (SNR) was calculated. Then, MRI of ten iliofemoral arteries of six pigs was acquired by MRIG and surface coil. The difference in the SNRs of the arterial walls between different coils was compared. Histology examined the potential thermal injuries of the imaged vessels. The MRIG functioned with the 3.0 T MR scanner. The average SNR of the arterial walls was significantly higher with the MRIG than with the surface coils (76.22 ± 34.76 vs. 12.63 ± 4.25, P < 0.01). Histology showed no evidence of thermal injuries at the vessel walls. This study validated the feasibility of generating intravascular 3.0 T MRI of deep-seated arterial walls in large animals, which should facilitate the translation of this technique from 1.5 to 3.0 T MR scanner.  相似文献   
6.
The chemical composition, crystalline structure, surface morphology and photoluminescence spectra of Na-doped ZnO thin films with different heat treatment process were investigated by X-ray photoelectron spectroscopy, X-ray diffraction, atomic force microscopy and a fluorescence spectrometer. The results show that preferred orientation, residual stress, average crystal size and surface morphology of the thin films are strongly determined by the preheating temperature. The effects of preheating temperature on microstructure and surface morphology have been discussed in detail. The photoluminescence spectra show that there are strong violet & UV emission, blue emission and green emission bands. The violet & UV emission is ascribed to the electron transition from the localized level below the conduction band to the valence band. The blue emission is attributed to the electron transition from the shallow donor level of oxygen vacancies to the valence band, and the electron transition from the shallow donor level of interstitial zinc to the valence band. The green emission is assigned to the electron transition from the level of ionized oxygen vacancies to the valence band.  相似文献   
7.
A bright white organic light-emitting diode (OLED) has been successfully fabricated in which a greenish-white emitting host Bis-(2-(2-hydroxyphenyl) benzothiazole)zinc (Zn(BTZ)2) is doped with an orange-red fluorescent dye 5,6,11,12-tetraphenylnaphthacene (rubrene). The pure white light emission with CIE coordinates of (0.341, 0.334) is achieved at the driving voltage of 20 V, and the corresponding luminance and external quantum efficiency are 4000 Cd/m2 and 0.63%. On the other hand, the pure red, green, and blue (RGB) emissions are obtained from the white OLED combined well with RGB custom-built optical color filters (CFs) with peaks at 616, 556, and 456 nm, respectively. Moreover, based upon the color mixture principles, we build a model of multi-color display mixed by the pure RGB emissions under the controllable bias.  相似文献   
8.
非球面和梯度折射率在眼光学成象中的作用   总被引:9,自引:9,他引:0  
赵秋玲  王肇圻  张春书 《光子学报》2002,31(11):1409-1412
在Gullstrand-Le Grand眼模型的基础上,构造不同的眼光学模型,分别研究了角膜非球面、晶状体非球面和昌状体折射率在眼光学成象中的作用.通过比较各模型系统的Zernike标准多项式系数,分析了非球面和梯度折射率对眼光光系统各象差的影响.同时研究了不同模型调制传递函数的特性.  相似文献   
9.
It is demonstrated that the shapes and magnitudes of DNA writhe can be precisely manipulated solely through maneuvering the nucleotide sequence of DNA and without the assistance of topoisomerases.  相似文献   
10.
红外双波段双层谐衍射光学系统设计   总被引:9,自引:0,他引:9  
范长江  王肇圻  吴环宝  张梅 《光学学报》2007,27(7):266-1270
将谐衍射透镜应用在传统红外单波段佩茨瓦尔(Petzval)物镜上,设计得到工作波段处于3.4~4.2μm和8~11μm的红外双波段单层谐衍射光学系统。但单层谐衍射元件的衍射效率只在设计波长处衍射效率最高,随着波长相对设计中心波长向两侧偏离,主衍射级次的衍射效率逐渐下降。为提高含单层谐衍射元件光学系统的衍射效率,基于双层衍射元件衍射效率表达式研究了双层谐衍射元件的结构优化,给出了优化方法。设计出佩茨瓦尔型红外双波段双层谐衍射光学系统,其在3.4~4.2μm和8~11μm两个工作波段的衍射效率均达到90%以上,相比含有单层谐衍射面的光学系统衍射效率有了很大提升,提高了像面衬比度,完善了系统成像质量。  相似文献   
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