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随着社会的进步和发展,计算机网络通信技术已被应用到实际生活、生产的各个方面,对人们的生活、生产等产生了深刻的影响。为此,文章就计算机通信及网络远程控制技术在实际生活中的应用问题进行了探究,旨在借助先进科技促进社会实现更优质发展。 相似文献
3.
Intermetallic materials are bestowed by diverse ordered superlattice structures together with many unusual properties. In particular, the advent of chemically complex intermetallic alloys (CCIMAs) has received considerable attention in recent years and offers a new paradigm to develop novel metallic materials for advanced structural applications. These newly emerged CCIMAs exhibit synergistic modulations of structural and chemical features, such as self-assembled long-range close-packed ordering, complex sublattice occupancy, and interfacial disordered nanoscale layer, potentially allowing for superb physical and mechanical properties that are unmatched in conventional metallic materials. In this paper, we critically review the historical developments and recent advances in ordered intermetallic materials from the simple binary to chemically complex alloy systems. We are focused on the unique multicomponent superlattice microstructures, nanoscale grain-boundary segregation, and disordering, as well as the various extraordinary mechanical and functional properties of these newly developed CCIMAs. Finally, perspectives on the future research orientation, challenges, and opportunities of this new frontier are provided. 相似文献
4.
《International Journal of Hydrogen Energy》2022,47(34):15189-15197
Oxygen evolution reaction (OER) is a key process involved in many energy-related conversion systems. An ideal OER electrocatalyst should possess rich active sites and optimal binding strength with oxygen-containing intermediates. Although numerous endeavors have been devoted to the modification and optimization of transition-metal-based OER electrocatalysts, they are still operated with sluggish kinetics. Herein, an ion-exchange approach is proposed to realize the structure engineering of amorphous P–CoS hollow nanomaterials by utilizing the ZIF-67 nanocubes as the precursors. The precise structure control of the amorphous hollow nanostructure contributes to the large exposure of surface active sites. Moreover, the introduction of phosphorus greatly modifies the electronic structure of CoS2, which is thus favorable for optimizing the binding energies of oxygenated species. Furthermore, the incorporation of phosphorus may also induce the formation of surface defects to regulate the local electronic structure and surface environment. As a result of this, such P–CoS hollow nanocatalysts display remarkable electrocatalytic activity and durability towards OER, which require an overpotential of 283 mV to afford a current density of 10 mA cm?2, outperforming commercial RuO2 catalyst. 相似文献
5.
《International Journal of Hydrogen Energy》2022,47(69):29771-29780
Conjugated polymers have emerged as a promising class of organic photocatalysts for photocatalytic hydrogen evolution from water splitting due to their adjustable chemical structures and electronic properties. However, developing highly efficient organic polymer photocatalysts with high photocatalytic activity for hydrogen evolution remains a significant challenge. Herein, we present an efficient approach to enhance the photocatalytic performance of linear conjugated polymers by modifying the surface chemistry via introducing a hydrophilic adenine group into the side chain. The adenine unit with five nitrogen atoms could enhance the interaction between the surface of polymer photocatalyst and water molecules through the formation of hydrogen bonding, which improves the hydrophilicity and dispersity of the resulting polymer photocatalyst in the photocatalytic reaction solution. In addition, the strong electron-donating ability of adenine group with plentiful nitrogen atoms could promote the separation of light-induced electrons and holes. As a result, the adenine-functionalized conjugated polymer PF6A-DBTO2 shows a high photocatalytic activity with a hydrogen evolution rate (HER) of 25.21 mmol g?1 h?1 under UV-Vis light irradiation, which is much higher than that of its counterpart polymer PF6-DBTO2 without the adenine group (6.53 mmol g?1 h?1). More importantly, PF6A-DBTO2 without addition of a Pt co-catalyst also exhibits an impressive HER of 21.93 mmol g?1 h?1 under visible light (λ > 420 nm). This work highlights that it is an efficient strategy to improve the photocatalytic activity of conjugated polymer photocatalysts by the modification of surface chemistry. 相似文献
6.
土木工程施工课程作为土木工程及工程管理专业的学科基础课和核心专业课程,在疫情防控期间"停课不停教""停课不停学"的要求下,通过线上平台进行授课。由于土木工程施工课程内容庞杂、综合性强、实践性强,且章节之间关联性较弱,探究既能使学生快速适应,又能保证教学质量的在线教学方法至关重要。以华南某高校土木工程施工课程为例,基于中国大学MOOC、建筑云课、腾讯课堂、QQ群等线上平台讲授教学内容,并运用问卷调查对课程线上教学效果进行评价。结果表明,线上教学为学生提供了丰富灵活的学习方式,显著提高了学生的自主学习能力,扩大了学生的知识面,达到了较好的学习效果。 相似文献
7.
Pengcheng Li Xiuxia Xu Junjie Zhao Pragati Awasthi Xusheng Qiao Jincheng Du Xianping Fan Guodong Qian 《中国稀土学报(英文版)》2022,40(2):169-192
Significant developments have been made in the past few decades for lanthanide(Ln)ions doped fluorosilicate glass-ceramics(Flusi-GCs).As novel generation of luminescence materials with a wide range of applications,Flusi-GCs as a single host combine the advantages of glass and ceramics/crystals as well as fluorides and silicates.In this review,the chemical design principles and experimental procedures of Flusi-GCs are summarized in detail.Flusi-GCs are categorized as those containing PbxCd1-xF2,RF3(R=Y,La,Gd),MF2(M=Ca,Sr,Ba),xMF2-yRF3(R=Y,La-Lu),mAF-nRF3(A=Li,Na,K),KTF3(T=Zn,Mn)and K2 SiF6 nanocrystals(NCs).Theoretical breakthroughs mainly by molecular dynamic(MD)simulation have been recapitulated as efficient routes for composition-design,nano-crystallization-prediction,and performance-optimization of Flusi-GCs containing target fluoride NCs.Essential research progresses pertaining photonic applications have been made in random lasers,communication amplifiers,optical fibers,spectral converters,white light-emitting-diodes(WLEDs),and thermal sensors.In the end,we propose three future research directions for Flusi-GCs. 相似文献
8.
高效率地使用工程车辆是工程项目管理中节约成本的有效方法,无人监管环境下工程车辆的工况识别,是实现工程车辆高效率使用的有效手段。目前以GPS等技术为核心的车辆智能管理系统未对工程车辆进行工况识别,提出一种基于GRU循环神经网络的工程车辆工况识别方法,通过对工程车辆在不同工况下产生的音频信号进行分析,从中提取Mel倒谱系数作为主要特征,构建GRU循环神经网络模型进行训练和识别。实验结果表明,该方法可以实现对工程车辆工况的有效识别。 相似文献
9.
介绍了浙江石油化工有限公司新建的3 Mt/a柴油加氢精制装置,其配套使用中国石化石油化工科学研究院有限公司开发的催化剂级配技术,并实施了可根据原料供应及市场产品需求情况灵活调整切换的2种生产技术方案。1 a的安稳生产运行结果表明:该装置以直馏柴油为主原料,通过分馏塔的馏分切割及其侧线抽出,实现了稳产国Ⅵ柴油并兼产喷气燃料技术方案的工业化应用;在实施以兼产喷气燃料为主的生产技术方案时,通过调整常一线柴油的掺炼量,不仅可以生产含硫量小于10.0 μg/g的精制柴油产品,同时兼产所得到的喷气燃料产品含硫量小于0.5 μg/g,赛波特颜色号值大于30;在实施主产精制柴油组分方案时,通过掺炼质量分数为20%~40%的催化柴油,并使所提炼得到的精制柴油组分含硫量小于6.0 μg/g的前提下,这些精制柴油组分产品既可直接作为满足国Ⅵ柴油产品出厂待售,也可作为柴油调和组分储存待用于产品的进一步优化。 相似文献
10.
生物质基喷气燃料是指全部或大部分来源于生物资源的喷气燃料,符合清洁低碳、安全高效的现代能源体系的要求。以生物质基喷气燃料替代传统石油基喷气燃料有助于我国早日实现“碳达峰、碳中和”的远大目标。在阐述生物质基喷气燃料生产工艺的发展历程及生物质基喷气燃料应用现状的基础上,提出高密度的生物质基喷气燃料是未来喷气燃料的发展方向,具有多环结构的生物质是合成高密度生物质基喷气燃料组分的优质原料;同时,总结了高密度生物质基喷气燃料组分生产工艺的研究进展,展望了生物质基喷气燃料未来的发展及挑战。 相似文献