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排序方式: 共有7454条查询结果,搜索用时 31 毫秒
91.
Shaoting Lin Yueying Yang Jiahua Ni Yoichiro Tsurimaki Xinyue Liu Baoyang Lu Yaodong Tu Jiawei Zhou Xuanhe Zhao Gang Chen 《Advanced functional materials》2021,31(36):2103551
Surface wetting prevents surface fogging on transparent materials by facilitating filmwise condensation with specific chemistry, but suffers from material and geometry selectivity. Extreme environments associated with high humidity and mechanical loading further limit their anti-fogging persistence. Here, a stretchable anti-fogging tape (SAT) that can be applied to diverse transparent materials with varied curvatures for persistent fogging prevention is reported. The SAT consists of three synergistically combined transparent layers: i) a stretchable and tough layer with large elastic recovery, ii) an endurant anti-fogging layer insensitive to ambient humidity, and iii) a robustly and reversibly adhesive layer. The SAT maintains high total transmittance (>90%) and low diffuse transmittance (<5%) in high-humidity environments, under various modes of mechanical deformations, and over a prolonged lifetime (193 days tested so far). Two applications are demonstrated, including the SAT-adhered eyeglasses and goggles for clear fog-free vision, and the SAT-adhered condensation cover for efficient solar-powered freshwater production. 相似文献
92.
93.
The canonical problem of a grounded dielectric slab with a truncated upper conductor and a dielectric cover layer is solved by the Wiener-Hopf technique. The method yields the value of the reflection coefficient at the open edge and the equivalent edge admittance. Numerical results show that the presence of a cover layer increases both the conductance and the susceptance. An increase in the value of edge conductance corresponds to an increase in the radiated power and surface-wave power. An increase in the value of the susceptance corresponds to an increase in the fringing capacitance at the edge. This results in a reduction of the physical length of a resonant rectangular patch. On the basis of Wiener-Hopf analysis it is seen that the space-wave power and the power carried by the surface wave are separated from the total radiated power. The numerical results show that the radiation efficiency decreases with an increase in the cover layer thickness 相似文献
94.
95.
96.
97.
In this paper we show that pseudomorphically strained heterostructures of InAs
x
P1−x
/InP may be an alternative to lattice-matched heterostructures of In1−x
Ga
x
As
y
P1−y
/InP for optoelectronic applications. We first studied the group-V composition control in the gas-source molecular beam epitaxy
(GSMBE) of the GaAs1-x
P
x
/GaAs system. Then we studied GSMBE of strained InAs
x
P1−x
/InP multiple quantum wells with the ternary well layer in the composition range 0.15 <x < 0.75. Structural and optical properties were characterized by high-resolution x-ray rocking curves, transmission electron
microscopy, absorption and low-temperature photoluminescence measurements. High-quality multiple-quantum-well structures were
obtained even for highly strained (up to 2.5%) samples. The achievement of sharp excitonic absorptions at 1.06, 1.3 and 1.55μm at room temperature from InAs
x
P1−x
/InP quantum wells suggests the possibility of long-wavelength optoelectronic applications. 相似文献
98.
99.
One of the main drawbacks of orthogonal frequency division multiplexing (OFDM) is the high peak‐to‐average power ratio (PAPR) of the transmitted OFDM signal. Partial transmit sequence (PTS) technique can improve the PAPR statistics of an OFDM signal. As ordinary PTS technique requires an exhaustive search over all combinations of allowed phase factors, the search complexity increases exponentially with the number of sub‐blocks. In this paper, we propose a novel PTS technique with reduced complexity that each level inverts twice of phase factor bits from previous level. Then we also use initial random phase sequence to find the better search way of PAPR reduction. Numerical results show that the proposed method can achieve significant reduction in search complexity with little performance degradation. Copyright © 2006 John Wiley & Sons, Ltd. 相似文献
100.
Graphene‐semiconductor nanocomposites, considered as a kind of most promising photocatalysts, have shown remarkable performance and drawn significant attention in the field of photo‐driven chemical conversion using solar energy, due to the unique physicochemical properties of graphene. The photocatalytic enhancement of graphene‐based nanocomposites is caused by the reduction of the recombination of electron‐hole pairs, the extension of the light absorption range, increase of absorption of light intensity, enhancement of surface active sites, and improvement of chemical stability of photocatalysts. Recent progress in the photocatalysis development of graphene‐based nanocomposites is highlighted and evaluated, focusing on the mechanism of graphene‐enhanced photocatalytic activity, the understanding of electron transport, and the applications of graphene‐based photocatalysts on water splitting, degradation or oxidization of organic contaminants, photoreduction of CO2 into renewable fuels, toxic elimination of heavy metal ions, and antibacterial applications. 相似文献