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961.
Quantum sensing,using quantum properties of sensors,can enhance resolution,precision,and sensitivity of imaging,spectroscopy,and detection.An intriguing question is:Can the quantum nature(quantumness)of sensors and targets be exploited to enable schemes that are not possible for classical probes or classical targets?Here we show that measurement of the quantum correlations of a quantum target indeed allows for sensing schemes that have no classical counterparts.As a concrete example,in the case that the second-order classical correlation of a quantum target could be totally concealed by non-stationary classical noise,the higher-order quantum correlations can single out a quantum target from the classical noise background,regardless of the spectrum,statistics,or intensity of the noise.Hence a classical-noise-free sensing scheme is proposed.This finding suggests that the quantumness of sensors and targets is still to be explored to realize the full potential of quantum sensing.New opportunities include sensitivity beyond classical approaches,non-classical correlations as a new approach to quantum many-body physics,loophole-free tests of the quantum foundation,et cetera. 相似文献
962.
Harikishore Amaravadhi Chong Sherilyn Shi Min Ragunathan Priya Bates Roderick W. Grüber Gerhard 《Molecular diversity》2021,25(1):517-524
Molecular Diversity - Mycobacteria have shown enormous resilience to survive and persist by remodeling and altering metabolic requirements. Under stringent conditions or exposure to drugs,... 相似文献
963.
翼型绕翼流动对风力机整机性能产生重要影响.本文基于大涡模拟方法,得到风力机翼型非定常转捩流动.通过对压力流场的动态模态分解(DMD)分析,发现翼型层流分离泡的生成和发展为流动主要非定常特征,且该特征具有主要频率.预估得到高增长率T-S扰动波频率与DMD模态频率接近,发现高频变化的分离泡由边界层分离点下游不远处的T-S扰动波诱导K-H不稳定性而主导,以及中低频的DMD模态表现为T-S扰动波所引起的湍流结构.对比不同攻角下的DMD分解结果,发现上表面分离泡会逐渐向前移动,长度变短;而下表面分离泡略微后移,长度变化不大. 相似文献
964.
Novel CMOS image sensor pixel to improve charge transfer speed and efficiency by overlapping gate and temporary storage diffusing node 下载免费PDF全文
A novel CMOS image sensor(CIS) pinned photodiode(PPD) pixel, named as O-T pixel, is proposed and investigated by TCAD simulations. Compared with the conventional PPD pixel, the proposed pixel features the overlapping gate(OG)and the temporary storage diffusing(TSD) region, based on which the several-nanosecond-level charge transfer could be achieved and the complete charge transfer from the PPD to the floating node(FD) could be realized. And systematic analyses of the influence of the doping conditions of the proposed processes, the OG length, and the photodiode length on the transfer performances of the proposed pixel are conducted. Optimized simulation results show that the total charge transfer time could reach about 5.862 ns from the photodiode to the sensed node and the corresponding charge transfer efficiency could reach as high as 99.995% in the proposed pixel with 10 μm long photodiode and 2.22 μm long OG. These results demonstrate a great potential of the proposed pixel in high-speed applications. 相似文献
965.
Martin Robinson Chong Luo Patrick E. Farrell Radek Erban Apala Majumdar 《Liquid crystals》2017,44(14-15):2267-2284
We study nematic equilibria on a square with tangent Dirichlet conditions on the edges, in three different modelling frameworks: (i) the off-lattice Hard Gaussian Overlap and Gay–Berne models; (ii) the lattice-based Lebwohl–Lasher model; and the (iii) two-dimensional Landau-de Gennes model. We compare the modelling predictions, identify regimes of agreement and in the Landau-de Gennes case, find up to 21 different equilibria. Of these, two are physically stable. 相似文献
966.
JPC – Journal of Planar Chromatography – Modern TLC - In this study, three active components, namely, kaempferol, scopoletin, and vanillic acid, in the ethyl acetate extract of the herb... 相似文献
967.
网络日志数据作为亿万消费者的意图数据库,为研究消费者需求波动提供了有效的量化指标,研究以北京市二手房为例,首先构建网站浏览日志数据与房地产成交量的关联模型,根据用户购房意图对网站进行分类,以不同类型房产网站的浏览次数(PV)、用户数(UV)等数据衡量购房者的关注及需求波动,构建房产成交量的先行、一致和滞后指数并对其关系进行检验,构建的房产指数是对现有指标体系的补充,为房地产开发商、普通购房者、政府相关管理部门提供决策指导和参考依据. 相似文献
968.
主要研究Clifford分析中hypergenic函数的边值问题A(y)Ψ*+f(y)+B(y)Ψ*-f(y)=G(y)L(Ψ*+f(y),Ψ*-f(y)).首先讨论hypergenic拟Cauchy型积分的相关性质;其次利用Schauder不动点原理证明了非线性边值问题解的存在性;最后利用压缩映射原理证明了线性边值问题解的存在唯一性. 相似文献
969.
970.
E. A. Podorozhko G. R. Ul’yabaeva V. E. Tikhonov A. V. Grachev L. V. Vladimirov Yu. A. Antonov N. R. Kil’deeva V. I. Lozinsky 《Colloid Journal》2017,79(1):94-105
The microstructure of complex and composite poly(vinyl alcohol) (PVA) cryogels containing water-soluble chitosan hydrochloride (ChHC) of dispersed particles of water-insoluble chitosan base (Ch), respectively, has been studied by optical microscopy and attenuated total reflection FTIR spectroscopy. The macroporous morphology of cryogels has been studied using preparations in the form of thin (~10 μm) sections and discs 1 mm thick. The introduction of non-gelling additives (NaCl and ChHC) into an initial PVA solution causes significant changes in the size and shapes of macropores in the complex cryogels formed by freezing–defrosting, as compared with the pores in the samples obtained under the same conditions without additives. The reasons for the changes are the process of phase segregation and the influence of low- and high-molecular-weight electrolytes on crystallization of ice, which plays the role of a porogen upon cryotropic gelation of aqueous PVA solutions. As a result of an alkaline treatment of the complex cryogels, which transforms ChHC into Ch, microcoagulation of chitosan yields discrete, almost spherical, particles with sizes of about 1–5 μm. IR spectral studies have shown that concentration gradients of the gelling and nongelling polymers arise along the thickness of the gel discs, with PVA concentration prevailing near the lower surface and ChHC or Ch concentration dominating near the upper surface of the disc. 相似文献