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31.
32.
Modular Self‐Assembling Peptide Platform with a Tunable Thermoresponsiveness via a Single Amino Acid Substitution 下载免费PDF全文
《Advanced functional materials》2018,28(35)
The introduction of a stimulus‐responsive property is an effective way to increase the applicability of functional materials in the field of nanobiotechnology. Herein, a peptide platform is devised for constructing elastin‐like peptide amphiphiles (ELPAs) that exhibit a temperature‐responsiveness that can be easily tuned via a single N‐terminal amino acid substitution at the final step of peptide synthesis. Due to the modular property of peptides, the platform based on a miniaturized elastin‐like peptide (MELP) can be conjugated with various bioactive peptide sequences in diverse macromolecular topologies. First, the MELP platform is coupled with a short linear RGD peptide. The ELPAs of the peptide conjugates exhibit rapid aggregation (coacervation) and retard disaggregation in response to heating and cooling, respectively. Second, the platform is grafted with an α‐helical guest peptide in a lariat‐type structure, which forms ELPAs that undergo faster disassembly than the ELPAs without the guest peptide in response to temperature increases. Interestingly, the critical temperatures for the thermoresponsive behaviors are commonly dependent on the hydrophobic and aromatic properties of the N‐terminal amino acid residues. These results suggest that this peptide platform possesses great potential for use in the development of smart materials in wide‐ranging applications related to temperature change. 相似文献
33.
Fewer Defects in the Surface Slows the Hydrolysis Rate,Decreases the ROS Generation Potential,and Improves the Non‐ROS Antimicrobial Activity of MgO 下载免费PDF全文
Nemanja Anicˇić Marija Vukomanović Tilen Koklicˇ Danilo Suvorov 《Small (Weinheim an der Bergstrasse, Germany)》2018,14(26)
Magnesium oxide (MgO) is recognised as exhibiting a contact‐based antibacterial activity. However, a comprehensive study of the impact of atomic‐scale surface features on MgO's antibacterial activity is lacking. In this study, the nature and abundance of the native surface defects on different MgO powders are thoroughly investigated. Their impacts on the hydrolysis kinetics, antibacterial activity against Escherichia coli (ATCC 47076), Staphylococcus epidermidis and Pseudomonas aeruginosa and the reactive oxygen species (ROS) generation potential are determined and explained. It is shown that a reduction in the abundance of low‐coordinated oxygen atoms on the surface of the MgO improves its resistance to both hydrolysis and antibacterial activity. The ROS generation potential, determined in‐situ using a fluorescence microplate assay and electron paramagnetic resonance spectroscopy, is not an inherent property of the studied MgO, rather it is a side product of hydrolysis (only for the most highly defected MgO particles) and/or a consequence of the MgO/bacteria interaction. The evaluation of the mutual correlations of the hydrolysis, the antibacterial activity and the ROS generation, with their origin in the surface defects' peculiarities, led to the conclusion that the acid/base reaction between the MgO surface and the bacterial wall contributes considerably to the MgO's antibacterial activity. 相似文献
34.
为快速、精确地从云制造平台资源池中搜索到满足用户需求的资源,实现资源与需求的高效匹配,提出了一种资源需求高效匹配策略。首先,建立了资源与需求的形式化描述模型,在此基础上,采用改进的K-means聚类算法按基本信息进行聚类,对云服务池中的资源进行预处理,形成多个资源簇;其次,计算用户需求与各资源簇聚类中心基本信息的相似度,确立备选资源簇;最后,再分别从资源的状态信息、功能信息和服务信息3个方面对备选资源簇中的备选资源进行筛选匹配。实例分析和研究结果表明:与已有的匹配方法相比,该方法在保持较高匹配精度的同时具有更高的匹配效率。 相似文献
35.
36.
针对目前部分水文要素监测工作中还存在大量人工记载、计算、录入,成果出错率较高,时效性低, 监测业务融合度不够和内部管理难度大等方面的问题,深度融合互联网技术和水文监测业务,开展“互联网 + 水文监测”研究,设计并开发分局水文监测综合管理平台是十分必要的。深入分析水文监测各项业务流程,打造水文监测在线业务流、数据流和管理流,结合程序开发语言和互联网技术,完成惠州水文监测综合管理平台设计。平台在 2020 年 6 月东江流域洪水中进行实际应用,结果表明:平台实现水文监测要素人工作业无纸化、 自动化、智能化,进一步提高水文监测工作效率和信息化水平,具有很好的推广应用前景。 相似文献
37.
Advances in the field of medical sciences and medical technology, and
present-day challenges, such as an aging population, rising medical expenses, and
lifestyle-related diseases, have collectively catalyzed a research ecosystem termed
“smart wellness.” This article describes the establishment of a smart wellness service platform designed to empower individuals to create a sense of balance in
their lives. Step-by-step details include service model, design, and architectural
considerations. As a proof of concept, implementation details of a Health
Improvement and Management Systems (HIMS) Hub, a Smart Wellness Service
Platform deployed in six cities in South Korea, are presented. An on-site survey
conducted in Busan Metropolitan City reveals the percentage of satisfied users to
be 91.3%. Furthermore, data gathered from 27,236 physical evaluations of users
from a Busan city center over the period of April 2013 to May 2018 reveal that
males and females in their 50s and 60s account for the highest number of participants, while males in their 70s have a higher rate of participation than females
in the same age group. 相似文献
38.
《Ceramics International》2022,48(18):25808-25815
The harmless disposal of lead paste in the spent lead-acid batteries (LABs) remains an enormous challenge in traditional pyrometallurgical recycling. Here, we introduced a hydrometallurgical method for the recycling of the spent LABs’ waste to obtain the β-PbO as a novel zinc ion batteries (ZIBs) active material. The obtained β-PbO exhibits ultra-flat charge/discharge voltage platforms (0.21 mV/(mAh g?1)) and stable specific capacity. During the charge/discharge, the β-PbO spontaneously triggers the formation of (ZnSO4)[Zn(OH)2]3·5H2O (ZHS) micro-sheets as a surface passivation layer. Moreover, the ex-situ X-ray spectra reveal that the reversible phase transformation occurs between PbSO4 and Pb with the assistance of ZHS by adjusting the PH value on the electrode-electrolyte interface. The synergistic two-phase-reaction mechanism generates ultra-flat voltage platforms upon the charge/discharge. This “energy-saving and environment-friendly” recycling route eliminates the major source of emission of pollution particulates/gases compared to the traditional pyrometallurgical recycling, while at the same time replacing energy-consuming and environmentally detrimental processes of synthesis of current ZIBs cathodes. 相似文献
39.
为保证漂浮式风电场在环境载荷复杂的海洋环境中稳定正常工作,以半潜式平台为研究对象,建立了基于Umarine Semi Submersible平台的阵列式风电场。通过FORTRAN程序语言求解气动载荷,采用水动力学软件AQWA,基于辐射/绕射理论并结合有限元方法,研究了风波耦合作用下半潜式平台时频动态响应。结果表明:阵列半潜式平台漂浮式风电场可有效提升平台抗首摇、横摇能力;固定悬链线可降低平台横荡运动幅值与纵荡响应;共用系泊系统的阵列平台机舱振动稳定性更佳。 相似文献
40.
This paper presents a novel method to evaluate the characteristics of the spherical hydrostatic supporting system for the floated inertial platform in dynamic environments. This hydrostatic supporting system consists of eight suspension pads fixed on the inner sphere. The force model for each single suspension pad is established. The dynamic equations for the inner sphere are also derived from the geometrical configuration. The stable time and stable deviation of the inner sphere in different dynamic environments are calculated. The results show that the hydrostatic supporting system can make the inner sphere resistant to the vehicle acceleration effectively and omnidirectionally. 相似文献