MOF-Like 3D Graphene-Based Catalytic Membrane Fabricated by One-Step Laser Scribing for Robust Water Purification and Green Energy Production

Increasing both clean water and green energy demands for survival and development are the grand challenges of our age.Here,we successfully fabricate a novel multifunctional 3D graphene-based catalytic membrane(3D-GCM)with active metal nanoparticles(AMNs)loading for simultaneously obtaining the water purification and clean energy generation,via a“green”one-step laser scribing technology.The as-prepared 3D-GCM shows high porosity and uniform distribution with AMNs,which exhibits high permeated fluxes(over 100 L m^(−2) h^(−1))and versatile super-adsorption capacities for the removal of tricky organic pollutants from wastewater under ultra-low pressure-driving(0.1 bar).After adsorption saturating,the AMNs in 3D-GCM actuates the advanced oxidization process to self-clean the fouled membrane via the catalysis,and restores the adsorption capacity well for the next time membrane separation.Most importantly,the 3D-GCM with the welding of laser scribing overcomes the lateral shear force damaging during the long-term separation.Moreover,the 3D-GCM could emit plentiful of hot electrons from AMNs under light irradiation,realizing the membrane catalytic hydrolysis reactions for hydrogen energy generation.This“green”precision manufacturing with laser scribing technology provides a feasible technology to fabricate high-efficient and robust 3D-GCM microreactor in the tricky wastewater purification and sustainable clean energy production as well.

Effect of Ball Scribing on Iron Loss of CGO and HGO Electrical Steel

The effect of ball scribing on iron loss of conventional grain-oriented ( CGO) and high-permeability grain-oriented ( HGO) electrical steel was investigated. In this paper,ball scribing was achieved by self- designed ball scribing instrument and a computer-controlled system capable of providing high accuracy and automatic measurements was developed for the magnetisation and measurement at high and low flux densities. The results showed that after ball scribing,iron loss of two types of steel ( C711 and H668 ) apparently decreases ( 5. 5% and 8. 2% respectively after 16mm scribing at 1. 2T) ,and at high and low flux densities, CGO and HGO electrical steel performs differently. Through the formation and development of free magnetic poles and secondary magnetic domains due to compressive stress,primary magnetic domain spacing of grain- oriented electrical steel becomes smaller,which reflects as a reduction of iron loss in the macroscopic magnetic properties. Through iron loss formula derivation,the effect of domain refinement on grain-oriented electrical steel was also interpreted.

Effect of Ball Scribing on Power Loss Separation of Fe-3%Si Grain-oriented Silicon Steel

Power loss of Fe-3%Sigrain-oriented silicon steelwas measured after ballscribing with different spacing using a self-designed tool.Three different sections of power loss,including hysteresis loss,abnormalloss,and eddy current loss,were measured and calculated,respectively.The loss variation and ratio were analyzed based on the experimentaldata.At 1.0 T,hysteresis loss of tested steelwith scribing spacing of 8 mm descends by 8.2% compared to samples without scribing,which is similar to the totalloss variation,and abnormalloss descends by 16.8%.At 1.0 T,hysteresis loss ratio of the steelwith scribing spacing of 16 mm ascends from 55.7% to 57.9%,and eddy current loss increases from 17.4% to 24.1%,while abnormalloss descends from 26.9% to 23.7%.The experimentalresults show that the reduction of power loss after scribing is mainly due to decreasing of hysteresis loss and abnormalloss.

High-rate metal-free MXene microsupercapacitors on paper substrates

MXene is a promising energy storage material for miniaturized microbatteries and microsupercapacitors(MSCs).Despite its superior electrochemical performance,only a few studies have reported MXene-based ultrahigh-rate(>1000 mV s^(−1))on-paper MSCs,mainly due to the reduced electrical conductance of MXene films deposited on paper.Herein,ultrahigh-rate metal-free on-paper MSCs based on heterogeneous MXene/poly(3,4-ethylenedioxythiophene)-poly(styrenesulfonate)(PEDOT:PSS)-stack electrodes are fabricated through the combination of direct ink writing and femtosecond laser scribing.With a footprint area of only 20 mm^(2),the on-paper MSCs exhibit excellent high-rate capacitive behavior with an areal capacitance of 5.7 mF cm^(−2)and long cycle life(>95%capacitance retention after 10,000 cycles)at a high scan rate of 1000 mV s^(−1),outperforming most of the present on-paper MSCs.Furthermore,the heterogeneous MXene/PEDOT:PSS electrodes can interconnect individual MSCs into metal-free on-paper MSC arrays,which can also be simultaneously charged/discharged at 1000 mV s^(−1),showing scalable capacitive performance.The heterogeneous MXene/PEDOT:PSS stacks are a promising electrode structure for on-paper MSCs to serve as ultrafast miniaturized energy storage components for emerging paper electronics.

Fabrication of a biomimetic controllable adhesive surface by ultraprecision multistep and layered scribing and casting molding

Wedge-shaped microstructures have the ability to reproduce the excellent adhesive properties of geckos’feet because of their unique anisotropic structure.In particular,the controllability of the wedge-shaped microstructures on adhesion is beneficial to the undisturbed grasp or the capture of space targets.However,the problem currently remains of how to process it efficiently and with high quality.Here a strategy called ultraprecision multistep and layered scribing is proposed for the manufacture of the biomimetic controllable adhesive surface.The results show that the metal master mold prepared based on the manufacturing strategy has not only good surface topography but also high reliability and durability.Furthermore,the controllable adhesive surface of 1.96 cm2,fabricated by the proposed manufacturing strategy,has a normal adhesion of 1.012 N,and the corresponding shear friction and adhesion coefficient are 3.105 N and 4.82,respectively.Additionally,the controllable adhesive surface has been shown to be approximately superhydrophobic and also to possess the properties of controllable adhesion and dynamic adhesion.Also,after 250 adhesion-detachment cycles,the normal adhesion and shear friction only decrease by 5%and 3%,respectively.The research realizes an environmentally friendly and efficient method by which to manufacture a durable metal mold for fabricating a biomimetic controllable adhesive surface,laying a foundation for its effective application in the adherence of space-floating targets.

Effect of Ball Scribing on Magnetic Barkhausen Noise of Grain-oriented Electrical Steel

Effect of ball scribing on magnetic Barkhausen noise （MBN） of conventional grain-oriented （CGO） and high- permeability grain-oriented （HGO） electrical steel was investigated. The results showed that after ball scribing, root mean square of MBN （MBNrms） of CGO electrical steel increased 9.8% with 4 mm scribing spacing at 1.2 T, and that of HGO electrical steel apparently decreased 17.3% with 16 mm scribing spacing at 1.2 T. Through the formation and development of free magnetic poles and secondary magnetic domains due to compressive stress, primary magnetic domain space of grain-oriented electrical steel becomes smaller, which reflects as a variation of MBN in the macroscopic magnetic properties. Through correlation formula derivation of MBNrms and equilibrium distance between domain walls, effect of domain refinement on grain-oriented electrical steel was also interpreted, and optimum equilibrium distance between domain walls was determined.

Efect of Ball Scribing on Relative Permeability of Grain-oriented Electrical Steel

Efect of ball scribing on relative permeability of conventional grain-oriented（CGO） and high permeability grain-oriented（HGO） electrical steel was investigated. The samples were scribed with spacing of 2 mm, 4 mm, 8 mm and 16 mm. The results show that after ball scribing with 16 mm width at 1.0 T, relative permeability of both℃GO and HGO steels was increased by 109% and 80%, respectively. Relative permeability rises as the scribing space increases, with the movement of the peak value of relative permeability to a higher flux density. Relational models describing relative permeability and flux density were constructed with high accuracy based on experimental data. The experimental data curves were analyzed during the magnetizing process.

基于P2P的MMOG兴趣域内多播改进算法

针对SCRIBE在解决基于P2P的巨量多玩家网络游戏兴趣域内多播时,产生的多播效率低、游戏状态数据同步性差问题,提出一种SCRIBE改进多播算法,该算法考虑P2P网络中终端节点在带宽和计算能力上的异构性,同时保证同一组中节点具有共同的兴趣。仿真结果表明,该算法能够在较大程度上减小消息冗余和降低多播延迟,提高游戏状态数据的同步性。

一个基于P2P技术的分布式视频检索系统

分布式视频检索是当前网络环境下信息检索的重要技术和方式之一,能够改善传统视频检索技术的性能。本文在分析已有视频检索系统发展状况的基础之上,利用FreePastry分布式平台以及P2P网络的可扩展性、负载均衡和稳定性,研究构建基于P2P(Peer-to-Peer)的分布式视频检索系统的方法。利用倒排索引技术和模糊查询技术提高视频检索效率。实验结果表明该系统在扩展性、查全率和查询准确率等性能上取得了较好效果。

基于隐含组播转发拓扑结构的应用层组播协议研究

介绍应用层组播协议的分类,然后对基于隐含组播转发拓扑结构的应用层组播协议进行分析、总结,讨论了进一步的研究问题.

Laser scribed graphene for supercapacitors

Supercapacitors,with the merits of both capacitors for safe and fast charge and batteries for high energy storage have drawn tremendous attention.Recently,laser scribed graphene has been increasingly studied for supercapacitor applications due to its unique properties,such as flexible fabrication,large surface area and high electrical conductivity.With the laser direct writing process,graphene can be directly fabricated and patterned as the supercapacitor electrodes.In this review,facile laser direct writing methods for graphene were firstly summarized.Various precursors,mainly graphene oxide and polyimide were employed for laser scribed graphene and the modifications of graphene properties were also discussed.This laser scribed graphene was applied for electrochemical double-layer capacitors,pseudo-capacitors and hybrid supercapacitors.Diverse strategies including doping,composite materials and pattern design were utilized to enhance the electrochemical performances of supercapacitors.Featured supercapacitors with excellent flexible,ultrafinestructured and integrated functions were also reviewed.

EScribe:一种动态路由的Topic发布订阅系统

Scribe是一种经典的基于Topic的发布订阅系统,它通过分布式组播树将Event分发给订阅者.Scribe需要定期维护组播树,因此造成了大量冗余的Event传递和高昂的维护代价.提出一种基于Scribe的增强型Topic发布订阅系统,简称EScribe.EScribe利用布隆过滤器存储Pastry叶子节点的订阅信息,动态地调整下一跳路由.节点维护子树的间隔时间随着节点在组播树中的层次增大而加长.实验结果表明,EScribe大幅减小了冗余Event传递的数量和组播树规模,也明显减小了Event分发和组播树维护的代价.

Scribe最佳节点查找速度优化算法

Scribe提供了一种有效的算法可以较小的计算量查找到最佳节点。然而,该算法在查找的过程中,需要不断地进行网络临近性测量来比较、判断、查找最佳节点,耽误时间。特别是在中国电信和中国网通互联互通问题比较严重的网络环境下,情况会进一步恶化。为了更快地查找到最佳节点,减少最终用户的等待时间,解决应用层组播技术在中国应用的具体问题,充分利用了Scribe节点运行过程中的历史数据和已知的IP地址数据库,优化了Scribe最佳节点查找算法。模拟实验显示,该算法将最佳节点查找速度提高了5%左右。

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In December 2020,the United Nations Educational,Scientific and Cultural Organization(UNESCO)in scribed China's Taijiquan on the Representative List of the In tangible Cultural Heritage of Humanity.

Video Scribe手绘软件在微课制作中的应用——以护理学基础中“马斯洛基本需要层次论”为例

微课是以教学视频为载体,以主题明确的知识点为内容,以短小精悍为特点的一种教学形式。随着信息技术在教学中的广泛应用,基于微课的移动学习、远程学习和在线学习将会越来越普及。就微课的制作,推荐一款制作效果极佳的手绘软件Video Scribe。同时,以护理学基础中"马斯洛基本需要层次论"为例叙述该软件在微课制作中的应用过程及方法。

Friction stir based welding and processing technologies-processes,parameters,microstructures and applications:A review

Friction stir welding [FSW） has achieved remarkable success in the joining and processing of aluminium alloys and other softer structural alloys. Conventional FSW, however, has not been entirely successful in the joining, processing and manufacturing of different desired materials essential to meet the sophis- ticated green globe requirements. Through the efforts of improving the process and transferring the existing friction stir knowledge base to other advanced applications, several friction stir based daughter technologies have emerged over the timeline, A few among these technologies are well developed while others are under the process of emergence. Beginning with a broad classification of the scattered fric- tions stir based technologies into two categories, welding and processing, it appears now time to know, compile and review these to enable their rapid access for reference and academia. In this review article, the friction stir based technologies classified under the categol^J of welding are those applied for join- ing of materials while the remnant are labeled as friction stir processing （FSP） technologies. This review article presents an overview of four general aspects of both the developed and the developing friction stir based technologies, their associated process parameters, metallurgical features of their products and their feasibility and application to various materials. The lesser known and emerging technologies have been emphasized.

Fabrication of Humidity Sensors Based on Laser Scribed Graphene Oxide/SnO Composite Layers

Humidity sensors have been widely applied to detect environment humidity in various fields. However, most of humidity sensors cannot provide performance needed for high sensitivity and fast response. We report one type of capacitive-type humidity sensors composed of laser-scribed graphene(LSG) as sensing electrodes and graphene oxide/tin dioxide(GO/SnO2) as a sensing layer. The LSG is reduced graphene oxide(rGO) electrodes resulted from selective reducing of GO within a GO/SnO2 composite layer by laser scribing method, and the sensing layer is the un-scribed GO/SnO2 composite. The sensor fabrication is a one-step process which is facile and cost-efficient. When a mass ratio of GO:SnO2 in the composite reaches 1:1, the humidity sensor(named as LSG-GS1) has the best properties than other ratios, which exhibits high sensitivity in the range of 11%~97% relative humidity(RH). In addition, the LSG-GS1 also has very quick response/recovery time(20 s for adsorption and 18 s for desorption) when RH changes from 23% to 84%, and very good stability after monitoring for 41 days. Such excellent performances of the humidity sensor can be attributed to synergistic effect of SnO2 and GO within the composite layer.

A Real Space Monster

To hear people talk, there are "black holes" all around us: the U. S.deficit, the Russian economy, the residence of Japan’s Prime Minister.They are found wherever things seem to disappear without leaving a trace.Ever since Princeton physicist John Wheeler coined the term in 1967 to de-scribe an object whose gravily is so powerful that it swallows everythingaround it even light-this bizarre concept, which first emerged from E-