分布式储能应用模式及优化配置综述

为促进新能源的发展,解决大规模分布式电源（Distributed Generation, DG）直接接入配电网和负荷急剧增长对电网规划及运行带来的问题与潜在威胁。分布式储能技术得到了广泛应用,由于其具有快速功率吞吐能力、控制精度高、安装灵活、多主体利益等特点,可从根本上保障配电网供电的安全与稳定性。介绍了分布式储能的发展状况,根据其接入位置在分布式电源侧、中低压配电网侧和用户与微网侧详细归纳了近年来国内外各种分布式储能应用模式的研究成果,重点就其位置和容量的选择问题总结了分布式储能优化配置的各类数学模型及优化算法。并结合分布式储能在配置过程中存在的问题,对其发展趋势进行了展望。     

Saliency guided self-attention network for pedestrian attribute recognition in surveillance scenarios

Pedestrian attribute recognition is often considered as a multi-label image classification task. In order to make full use of attribute-related location information, a saliency guided sel-attention network ( SGSA-Net) was proposed to weakly supervise attribute localization, without annotations of attribute-related regions. Saliency priors were integrated into the spatial attention module ( SAM ). Meanwhile,channel-wise attention and spatial attention were introduced into the network. Moreover, a weighted binary cross-entropy loss ( WCEL) function was employed to handle the imbalance of training data. Extensive experiments on richly annotated pedestrian ( RAP) and pedestrian attribute ( PETA) datasets demonstrated that SGSA-Net outperformed other state-of-the-art methods.     

Face aging with pixel-level alignment GAN

Applied Intelligence - Face aging is of great significance in cross-time identity verification problem. However, there is still a huge gap between the synthesized face image and the real face in...     

Effects of Ti and Mn Co-substitution on P4mm BiFeO3: An Ab Initio Calculation

Tetragonal BiFeO₃ (BFO), which has a giant spontaneous polarization, has attracted a great deal of attention recently. In this paper, we systematically study the structural, magnetic, electronic and optic properties of BFO, BiFe_0.75Mn_0.25 O ₃ (BFMM), and BiFe_0.75Ti_0.125Mn_0.125 O ₃ (BFMT). Results show that doping Ti and Mn into the Fe sites increases the c/a ratio and enhances the magnetization of BiFeO₃ from 0 to 5 μ_B. The crystal symmetry changes from orthogonality to tetragonality with half of the Mn atoms being replaced by Ti in BiFe_0.75Mn_0.25 O ₃, which suppresses the energy splitting of the Mn 3d orbitals and thus enlarge the band gap to 1.21 eV for BiFe_0.75Ti_0.125Mn_0.125 O ₃. Our calculated Bader charge and charge density difference show that the smallest volume of BiFe_0.75Mn_0.25 O ₃ arises from the strong Mn–O bonds in BiFe_0.75Mn_0.25 O ₃. Further investigations indicate similar optical behaviors for BiFeO₃ and BiFe_0.75Ti_0.125Mn_0.125 O ₃. However, BiFe_0.75Mn_0.25 O ₃ exhibits strong absorption in the infrared region for the transition from O 2p to Mn \({e_{g}^{2}}\) and \(t_{2g}^{3}\).     

Reprogrammable Assembly of Molecular Motor on Solid Surfaces via Dynamic Bonds

Controllable assembly of molecular motors on solid surfaces is a fundamental issue for providing them to perform physical tasks. However, it can hardly be achieved by most previous methods due to their inherent limitations. Here, a general strategy is designed for the reprogrammable assembly of molecular motors on solid surfaces based on dynamic bonds. In this method, molecular motors with disulfide bonds can be remotely, reversibly, and precisely attached to solid surfaces with disulfide bonds, regardless of their chemical composition and microstructure. More importantly, it not only allows encoding geometric information referring to a pattern of molecular motors, but also enables erasing and re‐encoding of geometric information via hemolytic photocleavage and recombination of disulfide bonds. Thus, solid surfaces can be regarded as “computer hardware”, where molecular motors can be reformatted and reprogramed as geometric information.     

船舶舱室正压排烟方案优化及仿真分析

本文主要针对船舶模拟舱室的正压排烟进行研究,以期为现代船舶的消防建设提供参考,将烟控区抽离建模如下文图一,设计正交排烟方案,由实验结果的极差分析得到最优的正压排烟方案即:风速15m/s,出口开度1.2m,进口开度0.3m。针对最优方案,由Fluent仿真分析得到:烟气聚集的地方,温度要高于周围,旋涡的存在导致烟气的滞留,说明针对烟气流动路径的研究将有利于排烟效果的改善。     

Mechanical and Reaction Properties of Al/TiH2/PTFE under Quasi‐Static Compression

TiH₂ is introduced into Al/PTFE reaction system for the first time. In order to study the mechanical and reaction properties of Al/TiH₂/PTFE composites, five kinds of mixtures with different TiH₂ contents and the contrasting TiH₂/PTFE mixture are prepared. The true stress–strain curves and reaction phenomena are recorded during the quasi‐static compression experiments; The reaction residues are analyzed with XRD to understand the reaction mechanism. The results show that the introduction of TiH₂ can significantly influence the strength of the composites; With the increasing of TiH₂ content, the mechanical strength is firstly increase and then decrease; When the content is the same, the reinforcing effect of TiH₂ particles on PTFE matrix is greater than that of Al. Violent reaction are observed in the four Al/TiH₂/PTFE composites with the content of TiH₂ below 20%, but not in TiH₂/PTFE. Furthermore, compared with Al/PTFE material, special flames are found during the reaction of composites with TiH₂, which become even more obvious with the increasing of TiH₂ content. The material reaction mechanism denotes that the high temperature of the crack tip result in the reaction of Al and PTFE, which activates TiH₂ to release hydrogen and generate TiC, resulting TiH₂ to fully release its energy.

     

Patterning of Discotic Liquid Crystals with Tunable Molecular Orientation for Electronic Applications

The large‐area formation of functional micropatterns with liquid crystals is of great significance for diversified applications in interdisciplinary fields. Meanwhile, the control of molecular alignment in the patterns is fundamental and prerequisite for the adequate exploitation of their photoelectric properties. However, it would be extremely complicated and challenging for discotic liquid crystals (DLCs) to achieve the goal, because they are insensitive to external fields and surface chemistry. Herein, a simple method of patterning and aligning DLCs on flat substrates is disclosed through precise control of the formation and dewetting of the capillary liquid bridges, within which the DLC molecules are confined. Large‐area uniform alignment occurs spontaneously due to directional shearing force when the solvent is slowly evaporated and programmable patterns could be directly generated on desired substrates. Moreover, the in‐plane column direction of DLCs is tunable by slightly tailoring their chemical structures which changes their self‐assembly behaviors in liquid bridges. The patterned DLCs show molecular orientation–dependent charge transport properties and are promising for templating self‐assembly of other materials. The study provides a facile method for manipulation of the macroscopic patterns and microscopic molecular orientation which opens up new opportunities for electronic applications of DLCs.     

Nontoxic engineered virus nanofibers as an efficient agent for the prevention and detection of fungal infection

Nano Research - Candida albicans (C. albicans) infection has a high mortality rate in immunocompromised patients. Owing to the inefficiency of the current diagnostic system and the absence of...     

TiAl合金表面TiAlCrY/YSZ涂层高温长时间服役性能

TiAl合金具有低密度、高比强度的优异性能,是一种潜在的航空发动机用结构材料。TiAl合金的服役温度范围为700～900℃,在其表面制备高温热防护涂层可以进一步提高服役温度。本研究采用等离子喷涂技术在TiAl合金表面制备了新型TiAlCrY/YSZ涂层,并与传统的NiCrAlY/YSZ热障涂层进行高温长时间服役性能对比研究。结果发现, TiAlCrY/YSZ涂层在1100℃空气环境中服役300 h保持完好,表现出良好的高温性能,而NiCrAlY/YSZ涂层在1100℃的服役寿命不足100 h。显微分析结果表明, TiAlCrY黏结层表面会形成一层连续且致密的TGO,其主要成分为Al2O3,与YSZ涂层的界面兼容性良好。并且TGO在1100℃空气环境中服役300 h后,厚度仍<8μm。以上研究表明,与传统NiCrAlY/YSZ热障涂层相比, TiAlCrY/YSZ更适合作为TiAl合金表面的高温热防护涂层。