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71.
Huimin Yu Deyu Wang Huanyu Jin Pan Wu Xuan Wu Dewei Chu Yi Lu Xiaofei Yang Haolan Xu 《Advanced functional materials》2023,33(24):2214828
Improving interfacial solar evaporation performance is crucial for the practical application of this technology in solar-driven seawater desalination. Lowering evaporation enthalpy is one of the most promising and effective strategies to significantly improve solar evaporation rate. In this study, a new pathway to lower vaporization enthalpy by introducing heterogeneous interactions between hydrophilic hybrid materials and water molecules is developed. 2D MoN1.2 nanosheets are synthesized and integrated with rGO nanosheets to form stacked MoN1.2-rGO heterostructures with massive junction interfaces for interfacial solar evaporation. Molecular dynamics simulation confirms that atomic thick 2D MoN1.2 and rGO in the MoN1.2-rGO heterostructures simultaneously interact with water molecules, while the interactions are remarkably different. These heterogeneous interactions cause an imbalanced water state, which easily breaks the hydrogen bonds between water molecules, leading to dramatically lowered vaporization enthalpy and improved solar evaporation rate (2.6 kg m−2 h−1). This study provides a promising strategy for designing 2D-2D heterostructures to regulate evaporation enthalpy to improve solar evaporate rate for clean water production. 相似文献
72.
73.
针对昌吉油田吉7井区油藏南部部分油井投产后出现供液能力差、产量递减快、不能持续性生产的现状,开展了氮气辅助化学剂降黏技术的研究与应用。结合吉7井区油藏属性,对降黏剂的适应性进行了评价。实验结果表明,在吉7井区储层温度、矿化度条件下,该降黏剂对稠油具有较好的降黏效果(质量分数1.5%,降黏率75%~85%)。现场应用结果表明:该工艺的应用能够解决油井供液困难、不能连续生产的问题;共实施8井次,累计增油1 011.2t;与未注氮气的油井相比,使用氮气辅助工艺能够起到较为明显的助排作用和控制油井含水上升的作用。 相似文献
74.
75.
本文在流动余辉装置上,利用亚稳态惰性气体原子[He(2~3S)、Ne(~3P_(0,2))、Ar(~3P_(0,2))]与SOCl_2的专能反应,在(230-430nm)波段观察到了产物的发射谱,光谱归属为自由基SO(A~3∏_(2,1,0)→X~3∑~-)的跃迁。对光谱强度分析表明:SO(A→X)的偶极跃迁矩Re随核间距明显地变化。通过拟合,找出了这一变化的关系。另外,本文还计算了SO(A~3∏_0→X~3∑~-)跃迁的Franck-Condon因子。 相似文献
76.
Ruey-Shi Chu Kuan Min Lee 《Antennas and Propagation, IEEE Transactions on》1993,41(10):1464-1469
In a performance monitoring/fault isolation and correction (PM/FIC) system of a phased array antenna, a built-in transmission line embedded in the array aperture is used for signal injection to check the signal flow. The authors present an analysis of electromagnetic coupling between a twin-lead transmission line and a dipole element. An analysis of the coupling between a transmission line and a linear array of dipole elements over a ground plane has also been developed. The calculated data compared with the measured data favorably. A development of microstrip-line signal injectors embedded in an aperture of a 2D array of monopole excited parallel-plate waveguides has also been made. Measurements of the feed and aperture distributions have been made and the measured distributions follow the designed feed distribution closely 相似文献
77.
The spectral coupling characteristics in asymmetrical twin-core optical fibres under fusion tapering are investigated experimentally. It is found that appropriate filtering can be achieved by fusion tapering. It is evident that, with suitable choice of tapering length and fibre parameters, it is possible to fabricate economic all-fibre bandpass filtering devices for various applications.<> 相似文献
78.
The effect of thermal oxidation on the residual stress distribution throughout the thickness of heavily-boron-doped (p+ ) silicon films is studied. The deflection of p+ silicon cantilever beams due to residual stress variation throughout the film thickness is studied for as-diffused and thermally oxidized films. Cantilevers of as-diffused p+ silicon films display a positive curvature (or a negative bending moment), signified by bending up of the beams. Thermal oxidation of the films prior to cantilever fabrication by anisotropic etching modifies the residual stresses in the p+ film, specially in the near-surface region (i.e. the top 0.3 to 0.5 μm for the oxidation times used here), and can result in beams with a negative curvature even when the oxide is removed from the p+ silicon cantilever surface subsequent to cantilever fabrication 相似文献
79.
用微波光电导谱仪无接触、非破坏性地测量了多晶硅的微波光电导谱,推导了由光电导谱计算多晶硅样品的少子扩散长度和表面复合速度的计算方法,并由此算得了样品的少子扩散长度和表面复合速度。测试区域是一个直径为3mm的圆斑。这是一种简便而又准确的测试方法。这样的方法还适用于GaAs薄片材料少子扩散长度的测量和计算。 相似文献
80.
Microring resonator channel dropping filters 总被引:17,自引:0,他引:17
Little B.E. Chu S.T. Haus H.A. Foresi J. Laine J.-P. 《Lightwave Technology, Journal of》1997,15(6):998-1005
Microring resonators side coupled to signal waveguides provide compact, narrow band, and large free spectral range optical channel dropping filters. Higher order filters with improved passband characteristics and larger out-of-band signal rejection are realized through the coupling of multiple rings. The analysis of these devices is approached by the novel method of coupling of modes in time. The response of filters comprised of an arbitrarily large dumber of resonators may be written down by inspection, as a continued fraction. This approach simplifies both the analysis and filter synthesis aspects of these devices 相似文献