Structural optimization

结构优化
  • 文章类型: Journal Article
    具有复杂形态的无定形碳材料,可变碳层结构,丰富的缺陷,和可调孔隙率作为钾离子电池(PIBs)的阳极是有利的。合成无定形碳材料通常涉及碳质前体的热解。尽管如此,仍然缺乏通过前驱体配方实现无定形碳多方面结构优化的研究。在这里,氮掺杂的无定形碳纳米管(NACNTs)衍生自钴基金属有机骨架(CMOF)和石墨碳氮化物(g-CN)的新型复合前体。在前体中添加g-CN优化了无定形碳的结构,例如形态,层间间距,氮掺杂,和孔隙度。因此,NACNT表现出显著改善的电化学性能。在100mA/g和1000mA/g的电流密度下循环后,NACNTs的比容量分别增加了194%和230%,达到346.6mAh/g和211.8mAh/g,分别。此外,NACNTs阳极与用于全电池评估的有机阴极匹配。全电池在100mA/g的电流密度下达到106mAh/g的高比容量,保持阴极半电池的比容量的90.5%。该研究为无定形碳的多方面结构优化以提高钾离子的储存能力提供了有价值的参考。
    Amorphous carbon materials with sophisticated morphologies, variable carbon layer structures, abundant defects, and tunable porosities are favorable as anodes for potassium-ion batteries (PIBs). Synthesizing amorphous carbon materials typically involves the pyrolysis of carbonaceous precursors. Nonetheless, there is still a lack of studies focused on achieving multifaceted structural optimizations of amorphous carbon through precursor formulation. Herein, nitrogen-doped amorphous carbon nanotubes (NACNTs) are derived from a novel composite precursor of cobalt-based metal-organic framework (CMOF) and graphitic carbon nitride (g-CN). The addition of g-CN in the precursor optimizes the structure of amorphous carbon such as morphology, interlayer spacing, nitrogen doping, and porosity. As a result, NACNTs demonstrate significantly improved electrochemical performance. The specific capacities of NACNTs after cycling at current densities of 100 mA/g and 1000 mA/g increased by 194 % and 230 %, reaching 346.6 mAh/g and 211.8 mAh/g, respectively. Furthermore, the NACNTs anode is matched with an organic cathode for full-cell evaluation. The full-cell attains a high specific capacity of 106 mAh/gcathode at a current density of 100 mA/g, retaining 90.5 % of the specific capacity of the cathode half-cell. This study provides a valuable reference for multifaceted structural optimization of amorphous carbon to improve potassium-ion storage capability.
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  • 文章类型: Journal Article
    为了放大辐射壳的位移,提出了一种双壳IV型曲面水声换能器。通过Ansys有限元模拟,研究了换能器在不同阶段的振动模式以及在空气和水中的谐波响应特性,实现了水声换能器的带宽发射。通过优化每个组件的尺寸,换能器的谐振频率为740Hz,最大电导率为0.66mS,最大发射电压响应为130dB。根据优化后的参数,制造了纵向声换能器原型,在无回声池中进行了物理测试。得到的谐振频率为750Hz,最大电导率为0.44mS,最大发射电压响应为129.25dB,最大线性尺寸为250毫米,与虚拟样机的仿真值相匹配,满足预期要求。
    To amplify the displacement of the radiation shell, a double-shell type-IV curved hydroacoustic transducer was proposed. Through Ansys finite element simulation, the vibration modes of the transducer in different stages and the harmonic response characteristics in air and water were studied, and the bandwidth emission of the hydroacoustic transducer was achieved. By optimizing the size of each component, the resonant frequency of the transducer is 740 Hz, the maximum conductivity was 0.66 mS, and the maximum transmitting voltage response was 130 dB. According to the optimized parameters, a longitudinal acoustic transducer prototype was manufactured, and a physical test was conducted in an anechoic pool. The obtained resonant frequency was 750 Hz, the maximum conductivity was 0.44 mS, the maximum transmitting voltage response was 129.25 dB, and the maximum linear dimension was 250 mm, which match the simulated value of the virtual prototype and meet the expected requirements.
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  • 文章类型: Journal Article
    声学致动纳米机械磁电(ME)天线代表了一种有前途的新技术,与传统天线相比,可以将天线尺寸显着减小1-2个数量级。然而,目前的ME天线面临着天线增益低、工作带宽窄等挑战,限制其工程应用。在本文中,我们通过结构优化来提高ME天线的带宽和辐射性能,利用理论分析和数值模拟。我们的发现表明,优化环形ME天线的内径可以提高磁层的平均应力,与圆形ME天线相比,提高了辐射性能和带宽。我们建立了ME天线辐射性能的优化模型,并使用COMSOLMultiphysics进行了形状优化仿真。多物理场优化的结果与应力集中理论一致,证明了ME天线的辐射性能和带宽与磁性膜的平均应力之间的强相关性。厚度振动模式中的谐振频率被确定为170MHz。此外,与相同尺寸的圆形ME天线结构相比,形状优化可以将带宽提高104%。
    The acoustically actuated nanomechanical magnetoelectric (ME) antennas represent a promising new technology that can significantly reduce antenna size by 1-2 orders of magnitude compared to traditional antennas. However, current ME antennas face challenges such as low antenna gain and narrow operating bandwidth, limiting their engineering applications. In this paper, we enhance the bandwidth and radiation performance of ME antennas through structural optimization, leveraging theoretical analysis and numerical simulations. Our findings indicate that optimizing the inner diameter of the ring-shaped ME antenna can elevate the average stress of the magnetic layer, leading to improved radiation performance and bandwidth compared to circular ME antennas. We establish an optimization model for the radiation performance of the ME antenna and conduct shape optimization simulations using COMSOL Multiphysics. The results of the Multiphysics field optimization align with the stress concentration theory, demonstrating a strong correlation between the radiation performance and bandwidth of the ME antenna with the average stress of the magnetic film. The resonant frequency in the thickness vibration mode is determined to be 170 MHz. Furthermore, shape optimization can enhance the bandwidth by up to 104% compared to circular ME antenna structures of the same size.
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  • 文章类型: Journal Article
    考虑到低镍不锈钢的高强度和优异的生物相容性,本文的重点是使用有限元分析(FEA)结合响应面法(RSM)对由该材料制成的血管支架进行优化设计。目的是在保持薄的支架壁厚的同时实现支架的期望的压缩阻力。支架支撑单元宽度(H)的参数,支柱宽度(W),选择厚度(T)作为输入参数,而从有限元分析获得的输出参数包括压缩载荷,等效塑性应变(PEEQ),轴向缩短率,径向反冲率,和金属覆盖率。利用RSM的BoxBehnken设计(BBD)建立了输入参数和输出参数的数学模型。模型方程在约束条件下求解,和最佳结构参数,即H,W,T,最终确定为0.770毫米,0.100mm,和0.075毫米。在这种情况下,支架的压缩载荷达到目标值0.38N/mm;支架扩张导致的PEEQ较小;轴向缩短,径向反冲,和金属覆盖指数都在所需范围内最小化。
    Considering the high strength and excellent biocompatibility of low-nickel stainless steel, this paper focused on optimizing the design of a vascular stent made from this material using finite element analysis (FEA) combined with the response surface methodology (RSM). The aim is to achieve the desired compressive resistance for the stent while maintaining a thin stent wall thickness. The parameters of the stent\'s support unit width (H), strut width (W), and thickness (T) were selected as input parameters, while the output parameters obtained from FEA included the compressive load, the equivalent plastic strain (PEEQ), axial shortening rate, radial recoil rate, and metal coverage rate. The mathematical models of input parameters and output parameters were established by using the Box Behnken design (BBD) of RSM. The model equations were solved under constrained conditions, and the optimal structural parameters, namely H, W, and T, were finally determined as 0.770 mm, 0.100 mm, and 0.075 mm respectively. In this situation, the compression load of the stent reached the target value of 0.38 N/mm; the PEEQ resulting from the stent expansion was small; the axial shortening, radial recoil, and metal coverage index were all minimized within the required range.
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  • 文章类型: Journal Article
    坏死性凋亡是受调节的坏死性细胞死亡的一种形式,已被证实在多种自身免疫性疾病如类风湿性关节炎(RA)和牛皮癣的发病机理中起关键作用。坏死凋亡抑制剂的开发可能为这些自身免疫性疾病的治疗提供有希望的治疗策略。在这里,从内部命中的化合物1开始,我们系统地进行了结构优化,以发现具有良好药代动力学特征的有效坏死凋亡抑制剂.所得化合物33是人I2.1细胞(IC50<0.2nM)和鼠Hepa1-6细胞(IC50<5nM)的有效坏死抑制剂。进一步的靶标鉴定表明,化合物33是具有良好选择性的受体相互作用蛋白激酶1(RIPK1)的抑制剂。此外,化合物33也表现出良好的药代动力学特征(T1/2=1.32h,Sprague-Dawley大鼠的AUC=1157ng·h/mL)。分子对接和分子动力学模拟证实化合物33可以高亲和力结合RIPK1。计算机模拟ADMET分析证明化合物33具有良好的药物相似性特征。总的来说,化合物33是发现抗生育药物的有希望的候选药物。
    Necroptosis is a form of regulated necrotic cell death and has been confirmed to play pivotal roles in the pathogenesis of multiple autoimmune diseases such as rheumatoid arthritis (RA) and psoriasis. The development of necroptosis inhibitors may offer a promising therapeutic strategy for the treatment of these autoimmune diseases. Herein, starting from the in-house hit compound 1, we systematically performed structural optimization to discover potent necroptosis inhibitors with good pharmacokinetic profiles. The resulting compound 33 was a potent necroptosis inhibitor for both human I2.1 cells (IC50 < 0.2 nM) and murine Hepa1-6 cells (IC50 < 5 nM). Further target identification revealed that compound 33 was an inhibitor of receptor interacting protein kinase 1 (RIPK1) with favorable selectivity. In addition, compound 33 also exhibited favorable pharmacokinetic profiles (T1/2 = 1.32 h, AUC = 1157 ng·h/mL) in Sprague-Dawley rats. Molecular docking and molecular dynamics simulations confirmed that compound 33 could bind to RIPK1 with high affinity. In silico ADMET analysis demonstrated that compound 33 possesses good drug-likeness profiles. Collectively, compound 33 is a promising candidate for antinecroptotic drug discovery.
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  • 文章类型: Journal Article
    为解决康复训练手套中软执行器的应用要求,并结合人体工程学要求,我们设计了一个带有弯曲和伸长模块的分段软执行器。该致动器可以实现手指关节的独立或耦合运动。
    建立了关节执行器的有限元模型,以比较具有不同结构形式的执行器的驱动性能。通过数值计算分析了结构尺寸参数对执行器弯曲特性和端部输出力的影响。然后基于这些分析改进设计。
    本研究中设计的关节执行器与标准快速气动网络结构相比,弯曲角度增加了71%。影响驾驶性能的关键因素包括约束层的厚度,腔室的内壁厚度,腔室高度,腔室宽度,腔室间距,腔室长度,和房间的数量。改进后,关节执行器的弯曲角度增加了60.6%,输出力增加了145.9%,表明显著改善。
    这项研究设计并改进了一种用于手部康复训练的软执行器,实现独立和耦合的关节运动。弯曲角度,弯曲形状,软执行器的关节驱动力满足手指康复训练的要求。
    UNASSIGNED: To address the application requirements of soft actuators in rehabilitation training gloves, and in combination with ergonomic requirements, we designed a segmented soft actuator with bending and elongation modules. This actuator can achieve independent or coupled movements of the finger joints.
    UNASSIGNED: A finite element model of the joint actuator was established to compare the driving performance of actuators with different structural forms. Numerical calculations were used to analyze the effects of structural size parameters on the bending characteristics and end output force of the actuator. The design was then refined based on these analyses.
    UNASSIGNED: The joint actuator designed in this study demonstrated a 71% increase in bending angle compared to the standard fast pneumatic network structure. Key factors affecting the driving performance include the thickness of the constraint layer, the inner wall thickness of the chamber, chamber height, chamber width, chamber spacing, chamber length, and the number of chambers. After improvements, the bending angle of the joint actuator increased by 60.6%, and the output force increased by 145.9%, indicating significant improvement.
    UNASSIGNED: This study designed and improved a soft actuator for hand rehabilitation training, achieving independent and coupled joint movements. The bending angle, bending shape, and joint driving force of the soft actuator meet the requirements for finger rehabilitation training.
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  • 文章类型: Journal Article
    植入血管中的生物可降解聚合物支架的临床性能受到不均匀降解的影响。应力分布在聚合物降解中起着重要作用,局部应力集中导致支架过早断裂。数值模拟结合体外实验验证可以准确描述降解过程并进行结构优化。与传统设计手法相比,基于代理模型的优化更科学有效。设计并优化了三种支架结构,以降解过程中的有效工作时间为优化目标。采用有限元方法模拟了支架的降解过程。采用代理模型来建立设计参数与降解性能之间的函数关系。所提出的功能模型准确地预测了各种支架的降解性能。优化后的支架结构表现出改善的降解性能,Kriging模型表现出了较好的优化效果。本研究为优化可生物降解聚合物支架的结构设计以提高其降解性能提供了一种新的方法。
    The clinical performance of biodegradable polymer stents implanted in blood vessels is affected by uneven degradation. Stress distribution plays an important role in polymer degradation, and local stress concentration leads to the premature fracture of stents. Numerical simulations combined with in vitro experimental validation can accurately describe the degradation process and perform structural optimization. Compared with traditional design techniques, optimization based on surrogate models is more scientifically effective. Three stent structures were designed and optimized, with the effective working time during degradation as the optimization goal. The finite element method was employed to simulate the degradation process of the stent. Surrogate models were employed to establish the functional relationship between the design parameters and the degradation performance. The proposed function models accurately predicted the degradation performance of various stents. The optimized stent structures demonstrated improved degradation performance, with the kriging model showing a better optimization effect. This study provided a novel approach for optimizing the structural design of biodegradable polymer stents to enhance degradation performance.
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  • 文章类型: Journal Article
    CelangulinV是一种新型的植物源杀虫剂,具有显著的生物活性和独特的分子靶标,但其复杂的多元醇酯结构阻碍了其在农业中的广泛应用。发现celangulinV具有更简单的结构和增强的生物活性的新类似物,我们发起了一个旨在简化其结构和评估杀虫功效的研究项目。在这项研究中,通过基于结构的合理设计方法设计了一系列新颖的1-四氢萘酮衍生物,并通过简单的方法合成。测定了目标化合物对Mythimnaseparata(M.分离),小菜蛾,还有Rhapalosiphumpadi.结果表明,与celangulinV相比,大多数合成的化合物表现出优异的活性。化合物6.16的杀虫活性比celangulinV对M.separata的胃毒性高102倍。此外,某些化合物对分离分枝杆菌表现出显著的接触毒性,在celangulinV的结构优化研究中以前没有报道过的发现。分子对接分析表明,化合物6.16与V-ATPaseH亚基的结合袋与celangulinV相同。这项研究为植物源农药的结构优化提供了新的见解。
    Celangulin V is a novel botanical insecticide with significant bioactivity and a unique molecular target, but its complex polyol ester structure hinders its broader application in agriculture. To discover new analogues of celangulin V with a simpler structure and enhanced biological activities, we initiated a research project aimed at simplifying its structure and assessing insecticidal efficacy. In this study, a series of novel 1-tetralone derivatives were designed via a structure-based rational design approach and synthesized by a facile method. The biological activities of the target compounds were determined against Mythimna separata (M. separata), Plutella xylostella, and Rhopalosiphum padi. The results revealed that most of the synthesized compounds exhibited superior activities compared to celangulin V. Remarkably, the insecticidal activity of compound 6.16 demonstrated 102-fold greater stomach toxicity than celangulin V against M. separata. In addition, certain compounds showed significant contact toxicity against M. separata, a finding not reported previously in the structural optimization studies of celangulin V. Molecular docking analysis illustrated that the binding pocket of compound 6.16 with the H subunit of V-ATPase was the same as celangulin V. This study presents novel insights into the structural optimization of botanical pesticides.
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  • 文章类型: Journal Article
    本文基于全球层面的证据,讨论了数字经济(DE)对碳排放的影响。具体来说,基于2010-2020年80个国家的面板数据,建立了DE测度指标,并运用System-GMM模型评估了DE对碳排放的影响。结果表明:(1)DE的发展显著促进了碳减排。(2)DE的发展通过技术进步显著促进了碳减排,结构优化,(3)监管质量和金融发展对DE对碳减排的促进作用具有积极的调节作用;(4)欧洲和北美国家的DE对碳减排的促进作用强于其他国家的DE。与发展中国家的DE相比,发达国家的DE对碳减排有较强的促进作用。此外,本文还发现制度差异会影响DE的碳减排效果。根据结果,本文建议全球各国政府应促进DE的发展,促进国际合作,以增强DE在促进碳减排中的推动作用。
    This paper discusses the influence of the digital economy (DE) on carbon emissions based on evidence at the global level. Specifically, based on the panel data from 80 countries from 2010 to 2020, this paper creates a DE measurement index and uses the System-GMM model to assess the influence of DE on carbon emissions. The results show that: (1) The development of DE significantly promotes carbon emissions reduction. (2) The development of DE significantly promotes carbon emissions reduction through technological advancement, structural optimization, and educational enhancement; (3) Regulatory quality and financial development play a positively moderating role in DE\'s promoting effect on carbon emissions reduction; (4) DE of European and North American nations have stronger promoting effect on carbon emissions reduction than DE of other countries. Compared to DE of developing countries, DE of developed countries has a stronger promoting effect on carbon emissions reduction. Additionally, this paper also finds that institutional differences can impact the carbon emission reduction effects of DE. Based on the results, this paper suggests that governments globally should promote the development of DE and foster international cooperation to enhance DE\'s driving role in promoting carbon emissions reduction.
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  • 文章类型: Journal Article
    土地利用变化深刻影响了全球环境动态。黄河(YR)作为世界第五长河,由于其广泛的流域面积,极大地促进了区域社会和经济的增长,使其成为关键的全球参与者。确保生态稳定,协调土地利用需求,对黄河流域(YRB)的未来土地分配模式进行建模将有助于在土地利用功能及其空间设计优化之间取得平衡,特别是在水和沙子管理方面。在这项研究中,我们使用多目标遗传算法(MOGA)和PLUS模型来模拟1990年至2020年YRB土地利用的几种不同未来,并预测其在2030年的空间格局。对YRB土地利用变化的时空演变分析表明,建设用地扩张是景观格局和结构变化以及生态退化的主要驱动力。气候变化也有助于流域面积的扩大。另一方面,多场景模拟,受特定目标的约束,揭示了经济发展主要体现在建设用地扩张上。同时,草地和林地是支持该地区生态健康的重要支柱,增加未利用土地的开发成为该地区实现可持续发展的潜在途径。通过阐明人类活动对土地利用的影响并在各种政策约束下合理化土地资源分配,本研究可作为其他大型流域长期增长的模板。
    Land use changes have profoundly influenced global environmental dynamics. The Yellow River (YR), as the world\'s fifth-longest river, significantly contributes to regional social and economic growth due to its extensive drainage area, making it a key global player. To ensure ecological stability and coordinate land use demand, modeling the future land allocation patterns of the Yellow River Basin (YRB) will assist in striking a balance between land use functions and the optimization of its spatial design, particularly in water and sand management. In this research, we used a multi-objective genetic algorithm (MOGA) with the PLUS model to simulate several different futures for the YRB\'s land use between 1990 and 2020 and predict its spatial pattern in 2030. An analysis of the spatiotemporal evolution of land use changes in the YRB indicated that construction land expansion is the primary driver of landscape pattern and structure changes and ecological degradation, with climate change also contributing to the expansion of the watershed area. On the other hand, the multi-scenario simulation, constrained by specific targets, revealed that economic development was mainly reflected in land expansion for construction. At the same time, grassland and woodland were essential pillars to support the region\'s ecological health, and increasing the development of unused land emerged as a potential pathway towards sustainable development in the region. This study could be used as a template for the long-term growth of other large river basins by elucidating the impacts of human activities on land use and rationalizing land resource allocation under various policy constraints.
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