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951.
Daniel K. L. Oi Alex Ling James A. Grieve Thomas Jennewein Aline N. Dinkelaker Markus Krutzik 《Contemporary Physics》2017,58(1):25-52
Bringing quantum science and technology to the space frontier offers exciting prospects for both fundamental physics and applications such as long-range secure communication and space-borne quantum probes for inertial sensing with enhanced accuracy and sensitivity. But despite important terrestrial pathfinding precursors on common microgravity platforms and promising proposals to exploit the significant advantages of space quantum missions, large-scale quantum test beds in space are yet to be realised due to the high costs and lead times of traditional ‘Big Space’ satellite development. But the ‘small space’ revolution, spearheaded by the rise of nanosatellites such as CubeSats, is an opportunity to greatly accelerate the progress of quantum space missions by providing easy and affordable access to space and encouraging agile development. We review space quantum science and technology, CubeSats and their rapidly developing capabilities and how they can be used to advance quantum satellite systems. 相似文献
952.
DanieldenEngelsen 《现代显示》2004,(4):29-32,24
液晶电视的优势使它很可能在本世纪的头十年内推翻CRT在电视市场的霸主地位。然而,那并不意味着真空显示器件将匆忙退出舞台,超薄型CRT会部分地与FPD显示器件在外型薄的优势方面展开竞争。甚至,它可以通过改进结构来显示出FED的特性。 相似文献
953.
Low-power W-band CPWG InAs/AlSb HEMT low-noise amplifier 总被引:1,自引:0,他引:1
Riemer P.J. Buhrow B.R. Hacker J.B. Bergman J. Brar B. Gilbert B.K. Daniel E.S. 《Microwave and Wireless Components Letters, IEEE》2006,16(1):40-42
We present the development of a low-power W-band low-noise amplifier (LNA) designed in a 200-nm InAs/AlSb high electron mobility transistor (HEMT) technology fabricated on a 50-/spl mu/m GaAs substrate. A single-stage coplanar waveguide with ground (CPWG) LNA is described. The LNA exhibits a noise figure of 2.5 dB and an associated gain of 5.6 dB at 90 GHz while consuming 2.0 mW of total dc power. This is, to the best of our knowledge, the lowest reported noise figure for an InAs/AlSb HEMT LNA at 90 GHz. Biased for maximum gain, the single-stage amplifier presents 6.7-dB gain and an output 1-dB gain compression point (P1dB) of -6.7dBm at 90 GHz. The amplifier provides broad-band gain, greater than 5dB over the entire W-band. 相似文献
954.
Jie?Mao Benjamin?Reeves Brendan?Lenz Daniel?Ruscitto Dan?LewisEmail author 《Journal of Electronic Materials》2017,46(11):6319-6332
Differential thermal analysis (DTA) has been conducted on directionally solidified near-eutectic Sn-3.0 wt.%Ag-0.5 wt.%Cu (SAC), SAC \(+\) 0.2 wt.%Sb, SAC \(+\) 0.2 wt.%Mn, and SAC \(+\) 0.2 wt.%Zn. Laser ablation inductively coupled plasma mass spectroscopy was used to study element partitioning behavior and estimate DTA sample compositions. Mn and Zn additives reduced the undercooling of SAC from 20.4\(^\circ \hbox {C}\) to \(4.9^\circ \hbox {C}\) and \(2^\circ \hbox {C}\), respectively. Measurements were performed at cooling rate of \(10^\circ \hbox {C}\) per minute. After introducing 200 ppm \(\hbox {O}_2\) into the DTA, this undercooling reduction ceased for SAC \(+\) Mn but persisted for SAC \(+\) Zn. 相似文献
955.
This paper proposes a hybrid decoupled power flow method for balanced power distribution systems with distributed generation sources.The method formulates the power flow equations in active power and reactive power decoupled form with polar coordinates.Second-order terms are included in the active power mismatch iteration,and constant Jacobian and Hessian matrices are used.A hybrid direct and indirect solution technique is used to achieve efficiency and robustness of the algorithm.Active power correction is solved by means of a sparse lower triangular and upper triangular(LU) decomposition algorithm with partial pivoting,and the reactive power correction is solved by means of restarted generalized minimal residual algorithm with an incomplete LU pre-conditioner.Typical distribution generation models and distribution load models are included.The impact of zero-impedance branches is explicitly modeled through reconfiguring of the adjacent branches with impedances.Numerical examples on a sample distribution system with widespread photovoltaic installations are given to demonstrate the effectiveness of the proposed method. 相似文献
956.
Brenda Long Mary Manning Micheal Burke Bartholomaeus N. Szafranek Giuseppe Visimberga Damien Thompson James C. Greer Ian M. Povey John MacHale Guaylord Lejosne Daniel Neumaier Aidan J. Quinn 《Advanced functional materials》2012,22(4):717-725
A simple, versatile method for non‐covalent functionalization of graphene based on solution‐phase assembly of alkane‐amine layers is presented. Second‐order Møller–Plesset (MP2) perturbation theory on a cluster model (methylamine on pyrene) yields a binding energy of ≈220 meV for the amine–graphene interaction, which is strong enough to enable formation of a stable aminodecane layer at room temperature. Atomistic molecular dynamics simulations on an assembly of 1‐aminodecane molecules indicate that a self‐assembled monolayer can form, with the alkane chains oriented perpendicular to the graphene basal plane. The calculated monolayer height (≈1.7 nm) is in good agreement with atomic force microscopy data acquired for graphene functionalized with 1‐aminodecane, which yield a continuous layer with mean thickness ≈1.7 nm, albeit with some island defects. Raman data also confirm that self‐assembly of alkane‐amines is a non‐covalent process, i.e., it does not perturb the sp2 hybridization of the graphene. Passivation and adsorbate n‐doping of graphene field‐effect devices using 1‐aminodecane, as well as high‐density binding of plasmonic metal nanoparticles and seeded atomic layer deposition of inorganic dielectrics using 1,10‐diaminodecane are also reported. 相似文献
957.
Daniel Dufresne Jose Garrido Manuel Morales 《Methodology and Computing in Applied Probability》2009,11(3):359-383
Several authors have used Fourier inversion to compute prices of puts and calls, some using Parseval’s theorem. The expected
value of max (S – K, 0) also arises in excess-of-loss or stop-loss insurance, and we show that Fourier methods may be used to compute them. In
this paper, we take the idea of using Parseval’s theorem further: (1) formulas requiring weaker assumptions; (2) relationship
with classical inversion theorems for probability distributions; (3) formulas for payoffs which occur in insurance. Numerical
examples are provided.
相似文献
958.
Blaschke Daniel N. Grosse Harald Kronberger Erwin Schweda Manfred Wohlgenannt Michael 《The European Physical Journal C - Particles and Fields》2010,69(3-4):575-579
The European Physical Journal C - Motivated by the success of the non-commutative scalar Grosse–Wulkenhaar model, a non-commutative U ⋆(1) gauge field theory including an... 相似文献
959.
We studied effect of 1-aminoanthracene (1-AMA) binding on the structures of dimeric β lactoglobulin, dimeric odorant binding
protein (OBP) and monomeric α1-acid glycoprotein (lipocalin family proteins) by monitoring fluorescence excitation spectra and measuring fluorescence lifetimes
of the tryptophan residues of the proteins. Results show that binding of 1-AMA to β lactoglobulin and OBP modifies their conformation
even at low probe concentration compared to that of the proteins. Structural modification induces a red shift of the fluorescence
excitation spectra maximum of tryptophan residues accompanied with an increase of the third fluorescence lifetime and a decrease
of its pre-exponential factor. These effects were not observed for α1-acid glycoprotein, probably as the result of carbohydrate presence. These data raise doubts concerning use of 1-AMA as a
probe to study biological properties of β lactoglobulin and OBP. 相似文献