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排序方式: 共有494条查询结果,搜索用时 93 毫秒
101.
Kaushik P. Seshadreesan Christoph F. Wildfeuer Moochan B. Kim Hwang Lee Jonathan P. Dowling 《Quantum Information Processing》2016,15(3):1025-1042
In two-mode interferometry, for a given total photon number N, entangled Fock state superpositions of the form \((|N-m\rangle _a|m\rangle _b+\mathrm{e}^{i (N-2m)\phi }|m\rangle _a|N-m\rangle _b)/\sqrt{2}\) have been considered for phase estimation. Indeed all such states are maximally mode-entangled and violate a Clauser–Horne–Shimony–Holt (CHSH) inequality. However, they differ in their optimal phase estimation capabilities as given by their quantum Fisher informations. The quantum Fisher information is the largest for the N00N state \((|N\rangle _a|0\rangle _b+\mathrm{e}^{i N\phi }|0\rangle _a|N\rangle _b)/\sqrt{2}\) and decreases for the other states with decreasing photon number difference between the two modes. We ask the question whether for any particular Clauser–Horne (CH) (or CHSH) inequality, the maximal values of the CH (or the CHSH) functional for the states of the above type follow the same trend as their quantum Fisher informations, while also violating the classical bound whenever the states are capable of sub-shot-noise phase estimation, so that the violation can be used to quantify sub-shot-noise sensitivity. We explore CH and CHSH inequalities in a homodyne setup. Our results show that the amount of violation in those nonlocality tests may not be used to quantify sub-shot-noise sensitivity of the above states. 相似文献
102.
Lin Zhao Feng Gao Michel C. Boufadel Thomas King Brian Robinson Kenneth Lee Robyn Conmy 《American Institute of Chemical Engineers》2017,63(11):5222-5234
Modeling the movement of oil released underwater is a challenging task due to limitations in measuring the hydrodynamics in an oil‐water system. In this work, we conducted an experiment of horizontal release of oil without and with dispersant. The model VDROP‐J was used and compared to the model JETLAG, a miscible plume trajectory model. Both models were found to reproduce the oil jet hydrodynamics for oil without and with dispersant. The predicted DSD from VDROP‐J matched closely observation for untreated oil. For oil with dispersant, experimental results have shown evidence that tip streaming occurred. For this purpose, a new conceptual module was developed in VDROP‐J to capture the tip streaming phenomenon and an excellent match was achieved with observation. This study is the first to report tip streaming occurring in underwater oil jets, which should have consequences on predicting the DSD when dispersant are used on an underwater oil release. © 2017 American Institute of Chemical Engineers AIChE J, 2017 相似文献
103.
介绍用甲烷(天然气)直接还原技术使冶炼烟气中SO2生成元素硫的工艺研究。SO2直接还原法分2 步:在高温下用甲烷将部分SO2还原成S和H2S,然后未反应的SO2和H2S发生Claus转化反应生成S。研究发现, 在工业装置中还原反应器宜采用分批甲烷法进料,以避免烟灰的生成;另需严格控制各种物料的相对比例,以确保位于Claus转化系列的硫冷凝器排出的尾气中的H2S/SO2为2,从而优化工艺性能。另外试验发现,在不同的停留时间下,SO2转化率与反应温度的关系曲线变化趋势是相反的,因此必须根据具体的现场条件选择停留时间。Siirtec Nigi公司和Albera硫研究有限责任公司联合开发了一种CH4/SO2还原/Claus/HCRTM工艺,其总硫回收率可达到99%以上。试验确定了一组有价值的化学工程数据,可用于该工艺的工业装置设计。 相似文献
104.
Lei Wang Jie-Hui Huang Jonathan P. Dowling Shi-Yao Zhu 《Quantum Information Processing》2013,12(2):899-906
We present a scheme of quantum information transmission, which transmits the quantum information contained in a single qubit via the quantum correlation shared by two parties (a two-qubit channel), whose quantum discord is non-zero. We demonstrate that quantum correlation, which may have no entanglement, is sufficient to transmit the information needed to reconstruct a quantum state. When the correlation matrix of the two-qubit channel is of full rank (rank three), the information of the qubit (in either a mixed state or a pure state) can be transmitted. The quantum discord of a channel with rank larger than or equal to three is always non-zero. Therefore, non-zero quantum discord is also necessary for our quantum information transmission protocol. The scheme may be useful in remote state tomography and remote state preparation. 相似文献
105.
Residential Building in Australia, 1993-2003 总被引:1,自引:0,他引:1
Robyn Dowling 《Urban Policy and Research》2005,23(4):447-464
The building of new houses is a significant urban activity. The built form, shape and liveability of Australian cities are directly influenced by the actions and characteristics of firms who build new dwellings (apartments and houses). Despite this importance, little is known about the types of firms that build new houses and apartments in Australia. This article provides a detailed analysis of the residential building sector in Australia between 1993 and 2003. Focusing on elements of the sector that have been identified as important for both theoretical and policy reasons, the article presents a fine-grained analysis of industry structure, levels of concentration and the characteristics of the sector's large firms. It finds that differentiations between residential builders across space and by type of dwelling constructed are increasingly important and that large residential builders increasingly share characteristics with firms involved in other property sectors. It suggests that diversified property conglomerates pose new challenges to urban governance and to international theories of residential building. 相似文献
106.
Victoria J. Butler Robyn Branicky Eviatar Yemini Jana F. Liewald Alexander Gottschalk Rex A. Kerr Dmitri B. Chklovskii William R. Schafer 《Journal of the Royal Society Interface》2015,12(102)
Although undulatory swimming is observed in many organisms, the neuromuscular basis for undulatory movement patterns is not well understood. To better understand the basis for the generation of these movement patterns, we studied muscle activity in the nematode Caenorhabditis elegans. Caenorhabditis elegans exhibits a range of locomotion patterns: in low viscosity fluids the undulation has a wavelength longer than the body and propagates rapidly, while in high viscosity fluids or on agar media the undulatory waves are shorter and slower. Theoretical treatment of observed behaviour has suggested a large change in force–posture relationships at different viscosities, but analysis of bend propagation suggests that short-range proprioceptive feedback is used to control and generate body bends. How muscles could be activated in a way consistent with both these results is unclear. We therefore combined automated worm tracking with calcium imaging to determine muscle activation strategy in a variety of external substrates. Remarkably, we observed that across locomotion patterns spanning a threefold change in wavelength, peak muscle activation occurs approximately 45° (1/8th of a cycle) ahead of peak midline curvature. Although the location of peak force is predicted to vary widely, the activation pattern is consistent with required force in a model incorporating putative length- and velocity-dependence of muscle strength. Furthermore, a linear combination of local curvature and velocity can match the pattern of activation. This suggests that proprioception can enable the worm to swim effectively while working within the limitations of muscle biomechanics and neural control. 相似文献
107.
Polyamidoamine prodrugs containing ferrocene derivatives and neridronate were successfully synthesized and characterized by NMR, FTIR, SEM, and EDX analyses. Appearance of characteristic peaks in 1H and 31P NMR or EDX spectra were used to confirm the presence of neridronate or ferrocene in the conjugates and co-conjugates. In vitro evaluation of the new materials revealed improved antimalarial activity, especially for conjugate 5 and corresponding co-conjugate 8, when compared with chloroquine and quinine. Hemolysis studies revealed that synthesized prodrugs had no effect on the integrity of the host red blood cell membrane; a direct effect on the intra-erythrocytic parasite was, however, noted. 相似文献
108.
Claudia Contini Rocío Álvarez Michael O'Sullivan Denis P. Dowling Sean Óg Gargan Frank J. Monahan 《Meat science》2014
An antioxidant active packaging was prepared by coating a citrus extract, consisting of a mixture of carboxylic acids and flavanones, on polyethylene terephthalate trays. The effect of the packaging in reducing lipid oxidation in cooked turkey meat and on meat pH, colour characteristics and sensorial parameters was investigated. An untrained sensory panel evaluated the odour, taste, tenderness, juiciness and overall acceptability of the meat, using triangle, paired preference and quantitative response scale tests. A comparison between the antioxidant effects of the different components of the extract was also carried out. The packaging led to a significant reduction in lipid oxidation. After 2 days of refrigerated storage the sensory panel detected differences in odour and, after 4 days, rated the meat stored in the active packaging higher for tenderness and overall acceptability. Citric acid appeared to be the most important component of the extract with regard to its antioxidant potency. 相似文献
109.
Enda P. Dowling William Ronan Gidon Ofek Vikram S. Deshpande Robert M. McMeeking Kyriacos A. Athanasiou J. Patrick McGarry 《Journal of the Royal Society Interface》2012,9(77):3469-3479
The biomechanisms that govern the response of chondrocytes to mechanical stimuli are poorly understood. In this study, a series of in vitro tests are performed, in which single chondrocytes are subjected to shear deformation by a horizontally moving probe. Dramatically different probe force–indentation curves are obtained for untreated cells and for cells in which the actin cytoskeleton has been disrupted. Untreated cells exhibit a rapid increase in force upon probe contact followed by yielding behaviour. Cells in which the contractile actin cytoskeleton was removed exhibit a linear force–indentation response. In order to investigate the mechanisms underlying this behaviour, a three-dimensional active modelling framework incorporating stress fibre (SF) remodelling and contractility is used to simulate the in vitro tests. Simulations reveal that the characteristic force–indentation curve observed for untreated chondrocytes occurs as a result of two factors: (i) yielding of SFs due to stretching of the cytoplasm near the probe and (ii) dissociation of SFs due to reduced cytoplasm tension at the front of the cell. In contrast, a passive hyperelastic model predicts a linear force–indentation curve similar to that observed for cells in which the actin cytoskeleton has been disrupted. This combined modelling–experimental study offers a novel insight into the role of the active contractility and remodelling of the actin cytoskeleton in the response of chondrocytes to mechanical loading. 相似文献
110.
Robyn Stevens 《Journal of the science of food and agriculture》2008,88(5):745-755
Maize (Zea mays L.) production in sub‐Saharan Africa has historically been constrained by a number of biotic and abiotic factors, including drought, insects, disease, and weeds. New agricultural research involving genomics and molecular markers may assist plant breeders in developing new varieties that will benefit producers and consumers in this region. Over the past few decades, plant breeders have used molecular markers to identify numerous genomic regions affecting maize production and nutritional value. Marker‐assisted selection (MAS) presents the potential to improve the efficiency of plant breeding by allowing for the transfer of these specific genomic regions of interest and accelerating the recovery of the elite parent background. However, to this point, few examples of successful MAS in breeding programs, particularly those with benefits in Africa, have been noted. This review discusses the use of molecular markers in the identification of quantitative trait loci (QTL) affecting the production and nutritional quality of maize, as well as the potential to use the results from the vast number of QTL studies that have been performed in MAS breeding programs. Copyright © 2008 Society of Chemical Industry 相似文献