Structural design

结构设计
  • 文章类型: Journal Article
    包容性设计不会停留在消除物理障碍,如楼梯。它还涉及识别施加感官负担的建筑特征,例如已知可能引起头晕或视觉不适的重复视觉模式。为了评估它们对人体步态及其稳定性的影响,三个重复模式随机点,重复条纹,和重复波(里斯本模式)-在虚拟现实(VR)环境中以彩色和灰度变体显示。使用运动捕捉系统和肌电图(EMG)记录了八名参与者的运动。在所有试验条件下,触地前发现腿部屈肌的肌肉活动显著增加。Further,在所有测试条件下,在摆动阶段观察到横向稳定肌肉的活动增加。使用线性混合模型(LMM)对横向和垂直质心(CoM)偏差进行统计学评估。图案确实导致CoM偏移在垂直方向上而不是在横向方向上的显著增加。这些发现表明抑制和更谨慎的步态风格以及控制策略的变化。此外,我们使用算法估计值和自我报告对诱发的不适进行了量化.基于傅立叶的方法比重复条纹更有利于灰度随机点。颜色度量比随机点更有利于条纹图案。参与者报告说,波浪状的里斯本模式最具破坏性。对于建筑和结构设计,这项研究表明:(1)考虑到高度重复模式对人体视觉运动系统的影响及其行为效应,应谨慎使用;(2)彩色模式应比灰度模式更谨慎使用.
    Inclusive design does not stop at removing physical obstacles such as staircases. It also involves identifying architectural features that impose sensory burdens, such as repetitive visual patterns that are known to potentially cause dizziness or visual discomfort. In order to assess their influence on human gait and its stability, three repetitive patterns-random dots, repetitive stripes, and repetitive waves (Lisbon pattern)-were displayed in a coloured and greyscale variant in a virtual reality (VR) environment. The movements of eight participants were recorded using a motion capture system and electromyography (EMG). During all test conditions, a significant increase in the muscular activity of leg flexor muscles was identified just before touchdown. Further, an increase in the activity of laterally stabilising muscles during the swing phase was observed for all of the test conditions. The lateral and vertical centre of mass (CoM) deviation was statistically evaluated using a linear mixed model (LMM). The patterns did cause a significant increase in the CoM excursion in the vertical direction but not in the lateral direction. These findings are indicative of an inhibited and more cautious gait style and a change in control strategy. Furthermore, we quantified the induced discomfort by using both algorithmic estimates and self-reports. The Fourier-based methods favoured the greyscaled random dots over repetitive stripes. The colour metric favoured the striped pattern over the random dots. The participants reported that the wavey Lisbon pattern was the most disruptive. For architectural and structural design, this study indicates (1) that highly repetitive patterns should be used with care in consideration of their impact on the human visuomotor system and its behavioural effects and (2) that coloured patterns should be used with greater caution than greyscale patterns.
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  • 文章类型: Journal Article
    在本文中,我们提出了无拉伸平面制造方案的优化,形状诱导的金属互连,以简化制造,目的是最大化结构中关于应力和应变的灵活性。硅岛之间的沟槽的形成被积极地用于光刻工艺中,以通过将抗蚀剂旋涂到沟槽中来产生弧形结构。所得的抗蚀剂形式用作金属线的模板,结构在顶部。因为这种弧形有利于这些桥的柔性。通过数值模拟研究了沟槽深度作为应力分布的关键参数。模拟结果表明,金属桥进入沟槽的穿透深度增加,拉伸载荷转化为剪切力Q(x)。这通常会导致结构可能产生的应变增加。对于制造,通过改变旋转速度来优化用抗蚀剂填充沟槽。与理论阻力相比,金属桥的电流-电压测量显示出类似的行为,并且几乎每个结构变化都能够在完整的岛桥阵列中充当柔性电气互连。
    In this paper, we present an optimization of the planar manufacturing scheme for stretch-free, shape-induced metal interconnects to simplify fabrication with the aim of maximizing the flexibility in a structure regarding stress and strain. The formation of trenches between silicon islands is actively used in the lithographic process to create arc shape structures by spin coating resists into the trenches. The resulting resist form is used as a template for the metal lines, which are structured on top. Because this arc shape is beneficial for the flexibility of these bridges. The trench depth as a key parameter for the stress distribution is investigated by applying numerical simulations. The simulated results show that the increase in penetration depth of the metal bridge into the trench increases the tensile load which is converted into a shear force Q(x), that usually leads to increased strains the structure can generate. For the fabrication, the filling of the trenches with resists is optimized by varying the spin speed. Compared to theoretical resistance, the current-voltage measurements of the metal bridges show a similar behavior and almost every structural variation is capable of functioning as a flexible electrical interconnect in a complete island-bridge array.
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  • 文章类型: Journal Article
    共价有机骨架(COF)是具有通过共价键交联的延伸的主链的结晶网络。由于半导体性质和可变的金属配位位点,随着连锁化学的迅速发展,COFs在光催化CO2RR中的应用引起了许多科学家的兴趣。在这篇评论中,综述了可变COFs光催化还原CO2的最新研究进展。在第一部分,我们介绍了CO2RR中使用的COF键的发展,我们讨论了四种机制,包括COFs作为内在光催化剂,具有光敏图案的COF作为光催化剂,金属化COF光催化剂,和COFs与半导体作为异质结光催化剂。然后,我们总结了结构设计的原则,包括功能建筑单元和堆叠模式交换。最后,已经提供了前景和挑战。本综述旨在为具有不同连接的不同COF的设计和合成提供一些指导,各种结构,和不同的堆叠模式,用于有效的CO2光还原。
    Covalent organic frameworks (COFs) are crystalline networks with extended backbones cross-linked by covalent bonds. Due to the semiconductive properties and variable metal coordinating sites, along with the rapid development in linkage chemistry, the utilization of COFs in photocatalytic CO2RR has attracted many scientists\' interests. In this Review, we summarize the latest research progress on variable COFs for photocatalytic CO2 reduction. In the first part, we present the development of COF linkages that have been used in CO2RR, and we discuss four mechanisms including COFs as intrinsic photocatalysts, COFs with photosensitive motifs as photocatalysts, metalated COF photocatalysts, and COFs with semiconductors as heterojunction photocatalysts. Then, we summarize the principles of structural designs including functional building units and stacking mode exchange. Finally, the outlook and challenges have been provided. This Review is intended to give some guidance on the design and synthesis of diverse COFs with different linkages, various structures, and divergent stacking modes for the efficient photoreduction of CO2.
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  • 文章类型: Journal Article
    太阳能界面蒸发是一种有前途且可持续的方法,具有海水淡化和废水处理的巨大潜力。尽管如此,创造持久的连续运行蒸发器提出了一个挑战。受自然自我修复机制的激励,这项研究开发了一种新型的3D混合空气水凝胶,其自我修复效率为89.4%,修复后断裂伸长率为637.7%,具有自我修复能力和持续运营潜力。尤其是,超支化水溶性聚合物(桃胶多糖)的掺入赋予最终的太阳能水蒸发器较低的水蒸发焓,导致精致的SVG3,具有明显的水面结构和扩大的蒸发面积,在1日太阳下实现了2.13kgm-2h-1的蒸汽产生率。值得注意的是,SVG2实现了2.43kgm-2h-1的高蒸发率,同时输入能量为1太阳和6V,在没有电压输入的情况下,显著超过1.96kgm-2h-1的速率。结果表明,电能显著增强和协同SVG,通过结合使用太阳能和电力输入,促进白天和黑夜的连续运行。本研究为太阳能水蒸发多功能水凝胶的战略设计提供了有见地的观点。
    Solar energy interfacial evaporation represents a promising and sustainable approach with considerable potential for seawater desalination and wastewater treatment. Nonetheless, creating durable evaporators for continuous operation presents a challenge. Motivated by natural self-healing mechanisms, this study developed a novel 3D hybrid aero-hydrogel, which exhibited a self-healing efficiency of 89.4 % and an elongation at break post-healing of 637.7 %, featuring self-healing capabilities and continuous operation potential. Especially, the incorporation of hyperbranched water-soluble polymers (peach gum polysaccharide) endow the final solar water evaporators with a lower evaporation enthalpy of water, resulting in that the refined SVG3, with a notable water surface architecture and an expanded evaporation area, achieved a steam generation rate of 2.13 kg m-2 h-1 under 1 Sun. Notably, SVG2 achieved a high evaporation rate of 2.43 kg m-2 h-1 with the combined energy input of 1 Sun and 6 V, significantly surpassing the rate of 1.96 kg m-2 h-1 without voltage input. The results indicate that electrical energy significantly enhances and synergizes with SVG, facilitating continuous operation both day and night through the combined use of solar energy and electrical input. This study offers insightful perspectives for the strategic design of multifunctional hydrogels for solar water evaporation.
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  • 文章类型: Journal Article
    软执行器提供了许多潜在的应用;然而,在实现高驱动力和快速响应速度方面仍然存在挑战。在这项工作中,我们提出的设计,fabrication,并分析了模拟水母水下肌肉运动的软气动双稳态执行器(PBA),以进行喷水推进。从水母喷射推进器和双稳态结构的特点中汲取灵感,我们开发了一种结构简单的弹性带拉伸预弯PBA,低通货膨胀成本,卓越的驾驶性能,和稳定的驱动力输出。通过对水母身体结构和运动的仿生分析,我们把PBA整合成水母一样的原型,使它能够实现喷气推进。为了提高游泳性能,我们介绍了一种类似皮肤的结构,用于将软致动器连接到类似水母的软机器人原型。这种皮肤状结构优化了喷射推进过程中的流体动力学,提高了效率和可操作性。我们的研究进一步分析了水母样原型的游泳性能,表现出3.8厘米/秒的游泳速度(0.32身体长度/秒,BL/s)用于系绳原型,4.7cm/s(0.38BL/s)用于未系绳原型。此外,与水下仿生机器人的其他驱动方法相比,我们展示了水母样原型的显着承载能力和快进游泳性能。这项工作为开发高度敏捷和快速响应的软机器人提供了宝贵的见解,这些软机器人模仿水母的下流肌肉,以实现高效的喷水推进,利用皮肤状结构来提高游泳性能。
    Soft actuators offer numerous potential applications; however, challenges persist in achieving a high driving force and fast response speed. In this work, we present the design, fabrication, and analysis of a soft pneumatic bistable actuator (PBA) mimicking jellyfish subumbrellar muscle motion for waterjet propulsion. Drawing inspiration from the jellyfish jet propulsion and the characteristics of bistable structure, we develop an elastic band stretch prebending PBA with a simple structure, low inflation cost, exceptional driving performance, and stable driving force output. Through a bionic analysis of jellyfish body structure and motion, we integrate the PBA into a jellyfish-like prototype, enabling it to achieve jet propulsion. To enhance the swimming performance, we introduce a skin-like structure for connecting the soft actuator to the jellyfish-like soft robot prototype. This skin-like structure optimizes the fluid dynamics during jet propulsion, resulting in improved efficiency and maneuverability. Our study further analyzes the swimming performance of the jellyfish-like prototype, demonstrating a swimming speed of 3.8 cm/s (0.32 body length/s, BL/s) for the tethered prototype and 4.7 cm/s (0.38 BL/s) for the untethered prototype. Moreover, we showcase the jellyfish-like prototype\'s notable load-bearing capacity and fast-forward swimming performance compared to other driving methods for underwater biomimetic robots. This work provides valuable insights for the development of highly agile and fast responsive soft robots that imitate the subumbrellar muscle of jellyfish for efficient water-jet propulsion, utilizing skin-like structures to enhance swimming performance.
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  • 文章类型: Journal Article
    柔性压阻式传感器在可穿戴设备、电子皮肤,和人机界面由于其有利的特点,包括低功耗,优异的弯曲稳定性,广泛的测试压力范围,和简单的制造技术。随着智能技术的进步,对灵敏度的要求更高,准确度,响应时间,测量范围,和耐候性的压阻式传感器正在兴起。由于聚合物多孔材料和导电相的可设计性,有了更多的多元组合,可以实现更高的灵敏度和更低的检测限,比传统的柔性传感器材料更有前途。基于此,这项工作回顾了利用聚合物多孔材料的柔性压力传感器研究的最新进展。此外,这篇综述从三维多孔柔性基底调节的角度研究了传感器性能的优化和发展,传感材料选择和复合技术,衬底和传感材料结构设计。
    Flexible piezoresistive sensors are in high demand in areas such as wearable devices, electronic skin, and human-machine interfaces due to their advantageous features, including low power consumption, excellent bending stability, broad testing pressure range, and simple manufacturing technology. With the advancement of intelligent technology, higher requirements for the sensitivity, accuracy, response time, measurement range, and weather resistance of piezoresistive sensors are emerging. Due to the designability of polymer porous materials and conductive phases, and with more multivariate combinations, it is possible to achieve higher sensitivity and lower detection limits, which are more promising than traditional flexible sensor materials. Based on this, this work reviews recent advancements in research on flexible pressure sensors utilizing polymer porous materials. Furthermore, this review examines sensor performance optimization and development from the perspectives of three-dimensional porous flexible substrate regulation, sensing material selection and composite technology, and substrate and sensing material structure design.
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  • 文章类型: Journal Article
    设计具有优异综合性能的耐热热固性塑料一直是一个长期的挑战。各种高性能热固性塑料的共固化是一种有效的策略,然而,传统的试错实验发现新材料的研究周期长。在这里,提出了一种两步机器学习(ML)辅助方法来设计由聚酰亚胺(PI)和含硅芳基乙炔(PSA)组成的耐热共固化树脂,也就是说,聚(硅-炔酰亚胺)(PSI)。首先,建立了两种ML预测模型来评估PI的加工性能及其与PSA的相容性。然后,开发了另外两个ML模型来预测共固化PSI树脂的热分解温度和弯曲强度。PSI树脂的最佳分子结构和组成是高通量筛选的。筛选的PSI树脂经过实验验证,具有增强的耐热性,韧性,和可加工性。在这项工作中建立的研究框架可以推广到其他先进的多组分聚合物材料的合理设计。
    Designing heat-resistant thermosets with excellent comprehensive performance has been a long-standing challenge. Co-curing of various high-performance thermosets is an effective strategy, however, the traditional trial-and-error experiments have long research cycles for discovering new materials. Herein, a two-step machine learning (ML) assisted approach is proposed to design heat-resistant co-cured resins composed of polyimide (PI) and silicon-containing arylacetylene (PSA), that is, poly(silicon-alkyne imide) (PSI). First, two ML prediction models are established to evaluate the processability of PIs and their compatibility with PSA. Then, another two ML models are developed to predict the thermal decomposition temperature and flexural strength of the co-cured PSI resins. The optimal molecular structures and compositions of PSI resins are high-throughput screened. The screened PSI resins are experimentally verified to exhibit enhanced heat resistance, toughness, and processability. The research framework established in this work can be generalized to the rational design of other advanced multi-component polymeric materials.
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  • 文章类型: Journal Article
    近年来,个性化诊断和治疗在生物医学和医疗保健领域得到了广泛认可和快速发展。由于灵活性,便携性和出色的兼容性,可穿戴超声(WUS)设备已成为新兴的个性化医疗设备,具有巨大的发展潜力。目前,随着超声换能器的材料和结构设计的不断进步,WUS装置具有改进的性能并且越来越多地应用于医疗领域。在这次审查中,我们提供了WUS设备的设计和结构的概述,从临床应用的角度着眼于它们在各种疾病的诊断和治疗中的应用,然后探讨临床翻译前需要解决的问题。最后,我们总结了WUS设备的开发进展,并讨论了当前面临的挑战和未来的发展方向。总之,WUS设备开创了生物医学的新兴时代,具有巨大的临床前景。
    In recent years, personalized diagnosis and treatment have gained significant recognition and rapid development in the biomedicine and healthcare. Due to the flexibility, portability and excellent compatibility, wearable ultrasound (WUS) devices have become emerging personalized medical devices with great potential for development. Currently, with the development of the ongoing advancements in materials and structural design of the ultrasound transducers, WUS devices have improved performance and are increasingly applied in the medical field. In this review, we provide an overview of the design and structure of WUS devices, focusing on their application for diagnosis and treatment of various diseases from a clinical application perspective, and then explore the issues that need to be addressed before clinical translation. Finally, we summarize the progress made in the development of WUS devices, and discuss the current challenges and the future direction of their development. In conclusion, WUS devices usher an emerging era for biomedicine with great clinical promise.
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  • 文章类型: Journal Article
    开发了一种基于生物可吸收Mg-Nd-Zn-Zr合金的可植入电极,用于下一代射频(RF)组织焊接应用,旨在减少热损伤,提高吻合口强度。镁合金焊条在焊接区域设计了圆柱面(CS)和连续长环(LR)不同的结构特征,并通过有限元分析(FEA)对电热模拟进行了研究。同时,监测组织焊接过程中的温度变化,并通过测量撕脱力和爆裂压力评估焊接组织的吻合强度。FEA结果表明,当将110V的交流电施加到LR电极10s时,焊接区域的平均温度和坏死组织的比例显着降低。在离体组织焊接实验中,LR电极焊接组织的最高温度和平均温度也明显降低,焊接组织的吻合强度明显提高。总的来说,应用LR电极后可获得满足临床要求的理想焊接温度和吻合强度,表明,优化结构设计的Mg-Nd-Zn-Zr合金显示出开发用于下一代射频组织焊接应用的植入式电极的巨大潜力。
    An implantable electrode based on bioresorbable Mg-Nd-Zn-Zr alloy was developed for next-generation radiofrequency (RF) tissue welding application, aiming to reduce thermal damage and enhance anastomotic strength. The Mg alloy electrode was designed with different structural features of cylindrical surface (CS) and continuous long ring (LR) in the welding area, and the electrothermal simulations were studied by finite element analysis (FEA). Meanwhile, the temperature variation during tissue welding was monitored and the anastomotic strength of welded tissue was assessed by measuring the avulsion force and burst pressure. FEA results showed that the mean temperature in the welding area and the proportion of necrotic tissue were significantly reduced when applying an alternating current of 110 V for 10 s to the LR electrode. In the experiment of tissue welding ex vivo, the maximum and mean temperatures of tissues welded by the LR electrode were also significantly reduced and the anastomotic strength of welded tissue could be obviously improved. Overall, an ideal welding temperature and anastomotic strength which meet the clinical requirement can be obtained after applying the LR electrode, suggesting that Mg-Nd-Zn-Zr alloy with optimal structure design shows great potential to develop implantable electrode for next-generation RF tissue welding application.
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  • 文章类型: Journal Article
    非水电解质,通常由金属盐和溶剂化介质组成,是构建可充电电池不可或缺的元素。作为离子电荷的主要来源,盐阴离子的固有特性在确定本体电解质的基本性质方面特别重要,以及所得电极-电解质界面/界面的特征。为了应对新兴应用领域对更好的可充电电池日益增长的需求,盐阴离子的结构设计和改性是非常需要的。这里,锂和其他单价的盐阴离子(例如,钠和钾)和多价(例如,镁,钙,锌,和铝)可充电电池概述。提供了盐阴离子设计的基本考虑因素,特别是涉及不同细胞化学强加的特定要求。回顾了具有代表性盐阴离子的金属盐的历史演变和可能的合成方法。仔细检查了为可充电电池定制阴离子结构的最新进展,适当注意从液体电解质到固体电解质的范式转变,从嵌入到转化/合金化型电极,从锂到其他类型的可充电电池。还讨论了稳健盐阴离子开发中的剩余挑战和关键研究方向。本文受版权保护。保留所有权利。
    Non-aqueous electrolytes, generally consisting of metal salts and solvating media, are indispensable elements for building rechargeable batteries. As the major sources of ionic charges, the intrinsic characters of salt anions are of particular importance in determining the fundamental properties of bulk electrolyte, as well as the features of the resulting electrode-electrolyte interphases/interfaces. To cope with the increasing demand for better rechargeable batteries requested by emerging application domains, the structural design and modifications of salt anions are highly desired. Here, salt anions for lithium and other monovalent (e.g., sodium and potassium) and multivalent (e.g., magnesium, calcium, zinc, and aluminum) rechargeable batteries are outlined. Fundamental considerations on the design of salt anions are provided, particularly involving specific requirements imposed by different cell chemistries. Historical evolution and possible synthetic methodologies for metal salts with representative salt anions are reviewed. Recent advances in tailoring the anionic structures for rechargeable batteries are scrutinized, and due attention is paid to the paradigm shift from liquid to solid electrolytes, from intercalation to conversion/alloying-type electrodes, from lithium to other kinds of rechargeable batteries. The remaining challenges and key research directions in the development of robust salt anions are also discussed.
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