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11.
Influences of the bag constant on the properties of hybrid stars are investigated by using relativistic mean field theory and the MIT bag model to describe the hadron phase and quark phase in the interior of neutron stars, respectively. Our results indicate that the onset of hadron-quark phase transition is put off and the appearance of hyperon species is increased with the increase in bag constant. As a result, the hybrid star equation of state for a mixed phase range stiffens whereas that of the quark phase range softens, and the gravitational mass as well as the corresponding radius of hybrid stars are increased obviously. The gravitational mass of a hybrid star is increased from 1.42 M (M is solar mass) to 1.63 M and the corresponding radius is changed from 9.1 km to 12.2 km when the bag constant (B1/4) is increased from 170 MeV to 200 MeV. It is interesting to find that hybrid star equations of state become non-smooth when the TM2 parameter sets in the framework of relativistic mean field theory used to describe the hadronic matter, and consequently, the third family of compact stars appear in the mass-radius relations of hybrid stars in the narrow scope of the bag constant from 175 MeV to 180 MeV. These show that the choice of the bag constant in the MIT bag model has significant influence on the properties of hybrid stars.  相似文献   
12.
Design of object surveillance system based on enhanced fish-eye lens   总被引:1,自引:0,他引:1  
A new method is proposed for the object surveillance system based on the enhanced fish-eye lens and the high speed digital signal processor (DSP). The improved fish-eye lens images an ellipse picture on the charge-coupled device (CCD) surface, which increases both the utilization rate of the 4:3 rectangular CCD and the imaging resolution, and remains the view angle of 183° The algorithm of auto-adapted renewal background subtraction (ARBS) is also explored to extract the object from the monitoring image. The experimental result shows that the ARBS algorithm has high anti-jamming ability and high resolution, leading to excellent object detecting ability from the enhanced elliptical fish-eye image under varies environments. This system has potential applications in different security monitoring fields due to its wide monitoring space, simple structure, working stability, and reliability.  相似文献   
13.
Xu N  Zhu J  Lu D  Zhou X  Peng X  Du J 《Physical review letters》2012,108(13):130501
Quantum algorithms could be much faster than classical ones in solving the factoring problem. Adiabatic quantum computation for this is an alternative approach other than Shor's algorithm. Here we report an improved adiabatic factoring algorithm and its experimental realization to factor the number 143 on a liquid-crystal NMR quantum processor with dipole-dipole couplings. We believe this to be the largest number factored in quantum-computation realizations, which shows the practical importance of adiabatic quantum algorithms.  相似文献   
14.
The magnetic reversal mechanism has been determined within a micromagnetic model reliably for a two-phased magnetic nanosystem,with the formulae for nucleation fields derived analytically.It is found that the nucleation field HN decreases uniformly as the size of the soft phase Ls increases whereas it increases with the size of the hard phase Lh.The analysis shows that whilst the effect of Lh could be ignored in most cases,where the nucleation field is dominated by the Ls and the calculation could be signif...  相似文献   
15.
cis-Neonicotinoid, in which the nitro and cyano pharmacophore point to the same position relative to the heteroaromatic moiety, is a further extension of the neonicotinoid library. While seeking new cis-neonicotinoid candidates, a series of tetrahydroimidazo[1,2-a]pyridinone derivatives were synthesized by reactions of nitromethylene analogs with itaconic anhydride. All the compounds were confirmed by 1H NMR, 13C NMR, and high-resolution mass spectroscopy. The target compounds had excellent insecticidal activities against cowpea aphids (Aphis craccivora) and brown planthopper (Nilaparvata lugens). Against armyworm, most of the compounds showed moderate activities. Interestingly, compound 12p was active against Tetranychus cinnabarinus. The synthesized compounds displayed good insecticidal activities against different insect species, which might provide useful guidance for further design of cis-neonicotinoid candidates.

[Supplementary materials are available for this article. Go to the publisher's online edition of Synthetic Communications® for the following free supplemental resource(s): Full experimental and spectral details.]  相似文献   

16.
In this paper,we calculate the production of a charged top pion in association with a W boson via gg fusion at CERN's Large Hadron Collider in the context of the topcolor assisted technicolor model.We find that the total cross section of pp→gg→W~(±)π_t~(■) is several dozen femtobarns with reasonable values of the parameters,and the total cross section of pp→W~(±)π_t~(■) can reach a few hundred femtobarns when we consider the sum of the contributions of these two parton subprocesses,gg→W~(±)π_t~(■) and b→W~...  相似文献   
17.
湿化学反应法制备了CaCuxMn3-xMn4 O12(x=0.2,0.4,0.6,0.8,1.0,1.2,1.4)系列材料的前驱体,然后通过高温烧结做成样品,进一步丰富了这类样品的研究内容.X射线衍射表明掺杂Cu2+在x=0.2到x=1.4范围内这些材料都能够成单相.通过Rietveld全谱拟合的方法分析,结果表明随掺...  相似文献   
18.
Here we report a simple and scalable method to fabricate high performance thin-film field-effect transistors(FETs) with high yield based on chemically functionalized single-walled carbon nanotubes(SWNTs) by organic radical initiators.The UV-Vis-NIR spectra,Raman spectra and electrical characterization demonstrated that metallic species in CoMoCat 65 and HiPco SWNTs could be effectively eliminated after reaction with some organic radical initiators.The effects of the substrate properties on the electrical pr...  相似文献   
19.
The present work examines the predictive capability of a two-fluid CFD model that is based on the kinetic theory of granular flow in simulating dilute-phase turbulent liquid–particle pipe flows in which the interstitial fluid effect on the particle fluctuating motion is significant. The impacts of employing different drag correlations and turbulence closure models to describe the fluid–particle interactions (i.e. drag force and long-range interaction) are examined at both the mean and fluctuating velocity l...  相似文献   
20.
Vapor-liquid phase equilibrium data of tertpentanol in carbon dioxide were measured at temperatures of 313.4,323.4,333.5 and 343.5 K and in the pressure range of 4.56 11.44MPa.The phase equilibium apparatus used in the work was a variable-volume high-pressure cell.The experimental data were reasonably correlated with Peng-Robinson equation of state(PR-EOS) together with van der Waals-2 two-parameter mixing rules.Henry's Law constants and partial molar volumes of CO2 at infinite dilution were estimated with ...  相似文献   
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