偏心T型套管内油水相分离研究

油水两相流经T型管时经常会不可避免地出现相分配不均现象,可以利用这个流动特性来实现两相预分离。结合浅池原理,本研究提出了一种偏心T型套管的新型设计,进一步提高油水分离效果。该分离系统包括上、下两层偏心套管,并通过两个立管相连通,且上外管顶端固接沿轴向延伸的浮油管。流体通过内管底部的狭长开缝在内外管之间流动,浮油通过上外管顶部开孔进入浮油管。这种设计能够降低雷诺数从而易于形成油水分层流动,而且狭长开缝能够极大地降低湍流强度,避免油水分离后重新掺混。文中研究了入口流型、油相速度、水相速度、混合速度以及含油率等因素对分离效率的影响,同时实验结果表明通过控制分流比使分离系统保持稳定良好的工作状态,且浮油管能够进一步提高该系统的分离效率

A thermal load identification method based on physics-guided neural network for honeycomb sandwich structures

The identification of thermal load/thermal shock of aircraft during service is beneficial for collecting information of the service environment and avoiding risks. In the paper, a method based on multivariate information fusion and physics-guided neural network is developed for the inverse problem of thermal load identification of honeycomb sandwich structures. Two thermal feature parameters: temperature gradient and temperature variation rate are used to build the dataset. A 16-layers physics-guided neural network is presented to achieve the predicted results consistent with physical knowledge. In the work, laser irradiation is used as the thermal load, and two laser parameters are to be identified, i.e. spot diameter, power. Simulations and experiments are conducted to verify the effectiveness of the proposed method. The effects of physics-guided loss function and multivariate information fusion are discussed, and it is found that the results based on the proposed method are much better than the results based on the method without physical model. Besides, results based on multivariate information fusion are better than results based on single temperature response. Then, the effects of network models and hyper parameters on the proposed method are also discussed

The mediating effect of personality between schizophrenia and prospective memory

目的 比较精神分裂症患者和正常对照的前瞻记忆差异,探讨人格在精神分裂症和前瞻记忆间的中介效应.方法 采用病例-对照的研究设计,用颜色匹配任务测两组的前瞻记忆成绩,用明尼苏达多项个性测量表简体中文版(MMPI-2)测量两组人格差异.结果 精神分裂症患者和正常对照组的前瞻记忆成绩为(19.29±2.30),(44.74±2.06),差异有统计学意义(t=-3.33,P＜0.01).在对人格的中介效应检验中,MMPI-2中的社会内向量表(Si)和焦虑紧张量表(ANX)的回归系数在依次检验中都显著(P＜0.05),即中介效应显著;对依次检验中只有一个系数有显著的量表采用sobel检验,结果发现两组被试的抑郁量表(D)、精神衰弱量表(Pt)和分裂症量表(Sc)的检验系数差异有统计学意义(P＜0.05),即中介效应也显著.结论 精神分裂症患者的前瞻记忆低于正常对照;MMPI-2所测量的抑郁、精神衰弱、分裂症、社会内向、焦虑紧张的人格特征在精神分裂症和前瞻记忆成绩间起着中介作用

Analysis of photonic crystal and multi-frequency terahertz microstrip patch antenna

In this paper, two-dimensional photonic crystals working at terahertz (THz) frequency is analyzed, a multi-frequency terahertz microstrip patch antenna on photonic crystal substrate is presented and its electromagnetic wave propagation phenomenon is investigated. The proposed antenna can work at five frequency points' scope at terahertz frequency regions, and the radiation efficiency is as high as similar to 96%. The photonic crystal structure of the substrate is used to enhance the gain, directivity and radiation efficiency of the antenna. (C) 2013 Elsevier B.V. All rights reserve

Extraordinary Transmission Based on Deep Perforated Sub-Wavelength Metallic Hole Arrays for Infrared Photodetector

In this paper, a new mode of deep perforated sub-wavelength metallic hole arrays in hexagonal lattice is presented. The transmission spectrum is obtained with Finite-difference time-domain (FDTD) and measured with Fourier infrared spectrometer. In the resonance peak scope, the Electric-field intensity is similar to 80 times larger than that of the incident wave at near field. The resonance of this structure can enhance the near-field intensity and improve the absorption efficiency of photodetector

Ultra-Wideband Multi-Frequency Terahertz Square Microstrip Patch Antenna on Hybrid Photonic Crystal Substrate

In this paper, two-dimensional photonic crystals working at terahertz frequency is investigated, and an ultra-wideband terahertz microstrip patch antenna on hybrid photonic crystal substrate is presented. Microwave Studio software is used to simulate its electromagnetic wave transmission properties. The proposed antenna can work at six frequency points' scope at terahertz frequency regions, and the 10 dB bandwidth is higher than ∼59%. The hybrid photonic crystal structure is able to provided ultra wide stop-band spectrum, in addition to advantages of the traditional photonic crystal structure which can enhance the gain, directivity and radiation efficiency of the antenna

The effect of Ga-doped nanocrystalline ZnO electrode on deep-ultraviolet enhanced GaN photodetector

Two types of GaN-based ultraviolet (UV) photodetectors were fabricated by using NiAu and Ga-doped ZnO (GZO) as electrode materials, respectively. Dark current-voltage and photoresponse characteristics of the devices were investigated. It is found that in addition to the similar to 365 nm cut-off response of GaN, an enhanced responsivity at around 250 nm is achieved for the GZO/GaN photodetectors. Photo absorption measurements provide proof that the efficient deep UV absorption occurs in the solar blind spectral zone. Transmission electron microscopy observations reveal the existence of nanostructures in the GZO thin film. Such nanostructures could be responsible for the deep UV photoresponse