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1.
We propose a test of nonlocality for continuous variables using a two-mode squeezed state as the source of nonlocal correlations and a measurement scheme based on conditional homodyne detection. Both the Clauser-Horne-Shimony-Holt and the Clauser-Horne inequality are constructed from the conditional homodyne data and found to be violated for a squeezing parameter larger than r approximately 0.48.  相似文献   
2.
We derive two classes of multimode Bell inequalities under local realistic assumptions, which are violated only by the entangled states negative under partial transposition in accordance with the Peres conjecture. Remarkably, the failure of local realism can be manifested by exploiting wave and particle correlations of readily accessible continuous-variable states, with very large violation of inequalities insensitive to detector efficiency, which makes a strong case for a loophole-free test.  相似文献   
3.
Park  Hyunchul 《Potential Analysis》2022,57(2):283-303
Potential Analysis - We investigate the 3rd term of the spectral heat content for killed subordinate and subordinate killed Brownian motions on a bounded open interval D = (a,b) in a real line when...  相似文献   
4.

Objective

The objective was to determine imaging features that distinguish small (≤3cm) solid pancreatic adenocarcinoma, neuroendocrine tumor (NET) and solid pseudopapillary tumor (SPT) on gadoxetic-acid-enhanced magnetic resonance imaging (MRI) and diffusion-weighed imaging (DWI).

Materials and methods

Twenty-four adenocarcinomas, 10 NETs and 8 SPTs were retrospectively included. Two radiologists analyzed morphologic features, signal intensity of the tumors on MR images including DWI (b=800) and dynamic enhancement pattern with consensus. Tumor-to-parenchyma ratio and tumor apparent diffusion coefficients (ADCs) were quantitatively assessed.

Results

All adenocarcinomas had an ill-defined margin and irregular shape, and more frequently had pancreatic duct dilatation compared with other tumors (P<.05). All SPTs and all but one of the adenocarcinomas (95.8%) had no arterial enhancement with progressively increased enhancement, whereas seven NETs (70%) had arterial enhancement with progressively decreased enhancement (P<.01). The mean value of tumor-to-parenchyma ratio on arterial and portal phases was significantly higher for NETs, and the mean value of tumor ADCs was significantly lower for SPTs than for other tumors (P<.05).

Conclusions

Gadoxetic-acid-enhanced MRI may aid in differentiation between small adenocarcinomas, NETs and SPTs based on morphologic features with dynamic enhancement pattern in adenocarcinomas, dynamic enhancement pattern with tumor-to-parenchyma ration on arterial and portal phases in NETs, and dynamic enhancement pattern with lower ADC value in SPTs.  相似文献   
5.
In our study, the physical properties of (TiO2) x (SiO2)1?x , including band-gap, band-offset, and thermal stability and the electrical properties of band-engineered SiO2/(TiO2) x (SiO2)1?x tunnel barrier stacks, including the tunneling current and charge-trapping characteristics for applications to nonvolatile memory devices were investigated. It was observed that the band-gap and band-offset of (TiO2) x (SiO2)1?x can be controlled by adjustment in the composition of the (TiO2) x (SiO2)1?x films. Ti-silicate film with TiO2:SiO2 cycle ratio of 1:5 was maintained in an amorphous phase, even after annealing at 950 °C. The tunneling current of the band-engineered SiO2/(TiO2) x (SiO2)1?x stacked tunnel barrier was larger than that of a single SiO2 barrier under a higher external bias, while the tunneling current of a SiO2/(TiO2) x (SiO2)1?x stacked tunnel barrier under a lower external bias was smaller. Charge-trapping tests showed that the voltage shift for SiO2/(TiO2) x (SiO2)1?x is slightly larger than that for single SiO2.  相似文献   
6.
7.
Various heterogeneous zinc glutarate (ZnGA) catalysts were synthesized in solvent systems of various polarities from zinc acetate dihydrate and glutaric acid with and without the aid of an amphiphilic block copolymer, poly(ethylene glycol‐b‐propylene glycol‐b‐ethylene glycol) (PE6400), as a template. The presence of the PE6400 template and the polarity of the solvent significantly affected the morphology, particle size, surface area, and crystallinity of the resulting catalyst. However, all the catalysts had the same crystal lattice unit cell structure and similar surface compositions. The surface compositions of the catalysts were quite different from those of conventionally prepared ZnGA catalysts, that is, those prepared from zinc oxide and glutaric acid in toluene. All these characteristics of the catalysts influenced the ZnGA‐catalyzed copolymerization of carbon dioxide and propylene oxide. The catalytic activities of the catalysts in this copolymerization depended primarily on their surface area and secondarily on their crystallinity; a larger surface area and a higher crystallinity resulted in higher catalytic activity. Of the catalysts that we prepared, the ZnGA catalyst that was prepared in ethanol containing 5.5 wt % water with the PE6400 template, ZnGA‐PE3, exhibited the highest catalytic activity in the copolymerization. The catalytic activity of ZnGA‐PE3 was attributed to its wrinkled petal bundle morphology, which provided a large surface area and high crystallinity. © 2005 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 43: 4079–4088, 2005  相似文献   
8.
The degree of entanglement in an open quantum system varies according to how information in the environment is read. A measure of this contextual entanglement is introduced based on quantum trajectory unravelings of the open system dynamics. It is used to characterize the entanglement in a driven quantum system of dimension 2 x infinity where the entanglement is induced by the environmental interaction. A detailed mechanism for the environment-induced entanglement is given.  相似文献   
9.
10.
In this paper, we study the asymptotic behavior, as the time t goes to zero, of the trace of the semigroup of a killed relativistic α-stable process in bounded C 1,1 open sets and bounded Lipschitz open sets. More precisely, we establish the asymptotic expansion in terms of t of the trace with an error bound of order t 2/α t ?d/α for C 1,1 open sets and of order t 1/α t ?d/α for Lipschitz open sets. Compared with the corresponding expansions for stable processes, there are more terms between the orders t ?d/α and t (2?d)/α for C 1,1 open sets, and, when α∈(0,1], between the orders t ?d/α and t (1?d)/α for Lipschitz open sets.  相似文献   
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