Pas de deux of electricity and magnetism: an interview with Sang-Wook Cheong

Materials can be ferroelectric, having a spontaneous electric polarization that can be reversed by an external electric field, or they can be ferromagnetic, exhibiting spontaneous magnetization that is switchable by an applied magnetic field. However, until the 1960s, scientists did not expect that these two ferroic properties could co-exist in a single material. Today, materials exhibiting more than one of the primary ferroic properties are called multiferroics. Here, the primary ferroic properties can be ferroelectricity, ferromagnetism, antiferromagnetism, ferroelasticity, ferrotoroidicity or others. Basically, the multiferroic effect originates from the simultaneous breaking of space inversion and time-reversal symmetries. Multiferroics can be imagined as a pas de deux of electricity and magnetism. Recently, National Science Review interviewed Professor Sang-Wook Cheong from Rutgers University, who is one of the pioneering scientists in this field. Cheong talked about the multiferroics field, which has been fast developing since the early 2000s. His introductions and opinions on diverse multiferroic materials and potential multiferroic devices, as well as future research directions, may provide a useful resource for researchers both inside and outside the multiferroic research field.     

高等院校教材选用制度探析

本文通过分析目前高校教材选用工作中存在的问题,结合自己工作实践、总结、探析、提出了以下几点提高教材选用质量的建议和措施;制定具体、规范的教材选用制度、建立教材信息平台、强化教材管理队伍,开展教材选编研究。本文通过分析目前高校教材选用工作中存在的问题,结合自己工作实践、总结、探析、提出了以下几点提高教材选用质量的建议和措施;制定具体、规范的教材选用制度、建立教材信息平台、强化教材管理队伍,开展教材选编研究。     

基于全生命周期理论的严寒地区建筑低碳发展潜力初探——以吉林省长春市为例

节约能源是我国的基本国策,在我国目前经济建设高速发展的情况下,建筑用能也在不断提高,这对我国能源供应和环境保护造成了巨大压力。建筑行业作为我国的耗能大户,并且是节能潜力最大的用能领域[1],逐渐成为节能工作关注的热点和重点。本文在全生命周期理论的基础上,以长春市典型的居住建筑和公共建筑为例,结合能耗模型的建立和计算,分析两种不同建筑类型在其生命周期不同阶段的能源消耗及其对环境产生的影响,探讨采取国家《节能减排综合性工作方案》中建筑节能措施后对建筑物所带来的低碳发展潜力。最后得出:在建筑过程节能方面,应注重建材循环使用所带来的能源效益;而在建筑使用节能方面,则应置力于提高能源的使用效率。     

Intrinsically flexible displays: key materials and devices

Continuous progress in flexible electronics is bringing more convenience and comfort to human lives. In this field, interconnection and novel display applications are acknowledged as important future directions. However, it is a huge scientific and technical challenge to develop intrinsically flexible displays due to the limited size and shape of the display panel. To address this conundrum, it is crucial to develop intrinsically flexible electrode materials, semiconductor materials and dielectric materials, as well as the relevant flexible transistor drivers and display panels. In this review, we focus on the recent progress in this field from seven aspects: background and concept, intrinsically flexible electrode materials, intrinsically flexible organic semiconductors and dielectric materials for organic thin film transistors (OTFTs), intrinsically flexible organic emissive semiconductors for electroluminescent devices, and OTFT-driven electroluminescent devices for intrinsically flexible displays. Finally, some suggestions and prospects for the future development of intrinsically flexible displays are proposed.     

二十一世纪初的材料科学技术

根据目前材料科学技术的动态 ,提出以下观点 :信息时代的信息功能材料仍是最活跃的领域 ;能源功能材料将取得实破性进展 ;生物材料在生命科学的带动下将有很大发展 ;智能材料与智能系统将得到更多的关注 ;随着资源的枯竭 ,环境的恶化 ,环境材料将日益受到重视 ;高性能结构材料的研究与开发是永恒的主题 ;材料制备工艺及测试方法是制约材料能否得到广泛应用的重要因素 ;纳米材料科学技术将成为 2 1世纪初最活跃的领域 ;2 1世纪将逐步实现按需设计材料。最后对不同类型材料的发展前景作了简要估计。     

Research policy and industrial materials

Many of the materials required by industry are similar to energy: resources are finite and the lifetime of the now known reserves varies. There is a need for R&D in this area if the trouble-free future operation of industry is to be safeguarded. There are many avenues R&D can, and should, follow - methods of exploration and extraction, recycling, better use of materials - which can postpone the emergence of scarcity. Much before this point is reached, the material becoming scarce will or should be substituted. This article suggests a method for selecting those materials in this very wide field which are likely to cause problems earlier than others. The dynamic nature of reserves, as known at present, is recognised; nevertheless, they are treated as a guide for relative adequacy.Life expectation and the arbitrarily estimated substitutability of 36 major materials are assessed; there are 15 among them with relatively short life expectation and/or whose replacement has not been solved or is difficult. These are surveyed in more detail. Some other aspects which may affect R&D requirements are also treated briefly. The manifold nature of the problems leads to the question of whether there is a need for some kind of an internationally institutionalised coordination.     

生物纳米材料的进展与前景

在过去几年中,生物纳米材料的理论与实验研究已成为人们关注的焦点,特别是核酸与蛋白质的生化、生物物理、生物力学、热力学与电磁学特征及其智能复合材料已成为生命科学与材料科学的交叉前沿。目前,纳米生物芯片材料、仿生材料、纳米马达、纳米复合材料、界面生物材料、纳米传感器与药物传递系统等方面已取得很大进展。本文主要对这些材料的研究、开发及应用情况进行了综述,并探讨了生物纳米材料的发展前景。     

情报视角下的高端人才评价体系构建及实证研究

[目的/意义]高端人才是现代社会国家竞争、城市竞争的核心要素。从情报的研究视角出发,构建了高端人才评价体系并进行了实践验证,以期为当前双创背景下高端人才的选拔使用提供一种科学可靠、客观公平的遴选方法。[方法/过程]立足情报学的研究视角,运用大数据搜集、文献库检索、情报分析、专家咨询与综合评价法等构建了包括3个维度18项指标的高端人才评价体系,并将其在超导材料领域进行了实践验证。[结果/结论]结果表明,基于情报视角构建的高端人才评价体系具有科学可靠性,可作为高端人才选拔使用的一种基本评价方法,其评价结果可在参考专家意见的基础上,作为人才引进、学术交流专家推荐、项目评审专家推荐的选择参考依据。     

Multiple UAV formations delivery task planning based on a distributed adaptive algorithm

In this paper, six-rotor UAVs are used in the field of distribution to realize the delivery of materials arriving the demand point by UAVs. Due to the small load capacity of the six-rotor UAV, in response to actual demand, the UAV group will be used to complete the delivery task. Considered to be close to the real requirements, trajectory constraints and dynamic obstacles are established in the trajectory planning based on group perception range. In order to better deal with dynamic obstacles and related constraints, this paper designs a distributed adaptive algorithm based on individual decision-making and group decision-making. Individual decision-making is embodied in the intelligence and adjustment of UAVs, involving actor-critic methods, artificial potential field method ideas and probability finite state machines; group decision-making is embodied in the leadership mechanism and joint decision-making; self-adaptation is embodied in the adaptive adjustment of UAV level in group. In order to avoid collisions between UAV groups, a conflict resolution algorithm is designed. Through simulation analysis, the distributed adaptive algorithm proposed in this paper can not only satisfy all constraints, avoid dynamic obstacles stably, and complete tasks with small fluctuations, but also obtain the most successful decision-making UAV in the group. This article further analyzes and discusses the relevant parameters in the algorithm, and obtains the optimal parameter ranges in individual decision-making and group decision-making.     

3D打印技术在建筑领域的应用及问题探析

我国对于作为第三次工业革命最具代表性技术之一的3D打印技术还处于探索阶段。针对材料选择、尺寸限制、安全性检验等阻碍推进3D打印技术在我国建筑领域应用的重大障碍,通过对3D打印技术在建筑领域适用性的分析及国内外的应用现状对比,从全寿命的角度出发梳理3D打印技术在决策阶段、实施阶段和使用阶段存在的问题,提出3D打印技术未来的发展方向,可以分成全尺寸打印、分段打印后现场装配和群组机器人打印3种模式;并建议未来进一步从材料、机器设备、标准体系、先进性技术、与传统建造方式协同发展等方向进行研究,促进3D打印技术在建筑领域中广泛应用。     

Black boxes on wheels: research challenges and ethical problems in MEA-based robotics

Robotic systems consisting of a neuron culture grown on a multielectrode array (MEA) which is connected to a virtual or mechanical robot have been studied for approximately 15 years. It is hoped that these MEA-based robots will be able to address the problem that robots based on conventional computer technology are not very good at adapting to surprising or unusual situations, at least not when compared to biological organisms. It is also hoped that insights gained from MEA-based robotics can have applications within human enhancement and medicine. In this paper, I argue that researchers within this field risk overstating their results by not paying enough attention to fundamental challenges within the field. In particular, I investigate three problems: the coding problem, the embodiment problem and the training problem. I argue that none of these problems have been solved and that they are not likely to be solved within the field. After that, I discuss whether MEA-based robotics should be considered pop science. Finally, I investigate the ethical aspects of this research.     

“变废为宝”--创设多彩高效的美术课堂

各种质感的废旧材料能引起中小学生学习手工制作的兴趣,激发学生的创造欲望,培养良好的节能环保意识。本文主要针对《美术课程标准》中提出：“在美术学习过程中,激发创造精神,发展美术实践能力”,结合设计应用和综合探索的学习领域展开研究。尝试各种工具、用生活中的各种废旧材料,体验美术活动的乐趣,在应用废旧材料制作过程中提高学生的创造能力与审美能力,激发学生兴趣,挖掘学生的创新潜能,从而培养学生“变废为宝”的艺术创作能力。将许多潜在着被回收和利用的废弃物,用我们的慧思巧手去将它们“化腐朽为神奇”。     

有机硅-丙烯酸树脂共聚方法述评

有机硅具有低表面张力，低玻璃化温度、良好的耐水、耐温、耐候等性能，这些优越性能为有机硅在高分子材料科学中的应用起着极为重要的作用。然而，由于有机硅的成本高、附着力及成膜性能较差，使它的进一步应用受到限制。鉴于此，许多有机硅工作者利用丙烯酸类物质对有机硅进行改性，不仅可以改善有机硅的缺点，而且还可以赋予这种复合材料许多新的性能。近年来，随着有机硅-丙烯酸树脂共聚物研究的不断深入，各种聚合方法也不断涌现。本文将以有机硅-丙烯酸树脂复合材料的类型为基础，对其中一些主要聚合方法的原理、优、缺点以及应用进行了比较详细的述评。     

北京新材料科研成果转化状况与政策建议

新材料、信息技术与生命科学并称为21世纪的三大关键技术,是高新技术发展的基础和先导.北京虽然拥有得天独厚的新材料科研资源,但由于长期以来以新材料规模化制造为发展方向,大量科研成果难以被有效转化.本文利用SWOT分析方法,对北京新材料科研成果转化的内部优势、劣势和外部机会、威胁进行了剖析,构建了北京新材料科研成果转化战略矩阵,并对北京新材料科研成果转化战略调整提出了政策建议.     

Hierarchically structured porous materials: synthesis strategies and applications in energy storage

To address the growing energy demands of sustainable development, it is crucial to develop new materials that can improve the efficiency of energy storage systems. Hierarchically structured porous materials have shown their great potential for energy storage applications owing to their large accessible space, high surface area, low density, excellent accommodation capability with volume and thermal variation, variable chemical compositions and well controlled and interconnected hierarchical porosity at different length scales. Porous hierarchy benefits electron and ion transport, and mass diffusion and exchange. The electrochemical behavior of hierarchically structured porous materials varies with different pore parameters. Understanding their relationship can lead to the defined and accurate design of highly efficient hierarchically structured porous materials to enhance further their energy storage performance. In this review, we take the characteristic parameters of the hierarchical pores as the survey object to summarize the recent progress on hierarchically structured porous materials for energy storage. This is the first of this kind exclusively to survey the performance of hierarchically structured porous materials from different porous characteristics. For those who are not familiar with hierarchically structured porous materials, a series of very significant synthesis strategies of hierarchically structured porous materials are firstly and briefly reviewed. This will be beneficial for those who want to quickly obtain useful reference information about the synthesis strategies of new hierarchically structured porous materials to improve their performance in energy storage. The effect of different organizational, structural and geometric parameters of porous hierarchy on their electrochemical behavior is then deeply discussed. We outline the existing problems and development challenges of hierarchically structured porous materials that need to be addressed in renewable energy applications. We hope that this review can stimulate strong intuition into the design and application of new hierarchically structured porous materials in energy storage and other fields.     

The 2006 Benjamin Franklin Medal in Chemistry presented to Samuel J. Danishefsky, Ph.D.

Organic synthesis of natural products began in 1828 with Wohler's synthesis of urea, the first time a substance derived from a living organism had been produced by combining inorganic materials. Progress in the field was slow at first, due to the limited purification and analytical methods. Advances in those areas gave rise to rapid progress in synthesis, as chemists could now focus their energies on devising new approaches to the preparation of increasingly complex molecules. While it is possible to prepare many molecules by using known chemistry in new combinations, real progress has been the result of keen insight and creativity on the part of only a few individuals.Professor Samuel J. Danishefsky established himself early on as a leader in this field when he recognized that a well-known ring forming reaction could be greatly extended by adding chemical functionality to one of the components. He then found that these new reactive components could react with heretofore unreactive components to produce new rings containing oxygen atoms both in the ring and as attachments to the ring. These products were very similar to naturally occurring sugars. Danishefsky realized that he could develop this chemistry further to produce precisely defined polysaccharides as well. Some of these polysaccharides occur on the surface of cancer cells. Using the chemistry he developed, he was able to prepare these cancer cell markers, and after combining them with certain proteins, showed that the resulting molecules behaved as cancer vaccines. Several have entered clinical trial.Danishefsky has synthesized many other natural products, but he is particularly interested in those that may be useful in treating cancer. His syntheses allow for the modification of the final product in ways that improve both safety and efficacy. Several of these compounds have also entered clinical trials. Thus his work has not only advanced the art and science of organic synthesis, but stands to make dramatic advances in the treatment of cancer as well.     

基于中国知网数据库的中国深潜技术文献研究

基于1980—2018年间研究中国深潜技术的811篇文献数据,运用文献计量、支持向量机(SVM)聚类分析以及可视化分析等方法,对中国深潜技术领域研究热点、热点年度变化、研究机构、作者及合作网络等情况进行综合分析。研究显示:中国深潜技术领域总体上受到持续关注,2010年以来文献数量呈现爆发性增长态势;研究热点集中在导航与通信、结构、控制等系统技术方面,对材料、生命支持(仅适用载人深潜器)等系统技术方面研究不足;军队系统与高校为研究主力,但合作研究未形成规模效应。     

全球高超声速技术发展态势分析

高超声速技术是未来航空航天领域的制高点,具有重要的战略性和前瞻性意义。文章采用文献计量/综述、国内外官方机构/权威网站调研等方法对全球高超声速技术发展态势进行分析。研究发现,针对高超声速技术的研究主要集中在军事领域,其中动力推进技术、制导与控制技术、新型材料和热防护技术等是该领域的研究重点方向。通过梳理各国研发态势发现,未来涉及高超声速武器研发的相关核心技术仍是研究的重点,同时各国正加快优先布局高超声速防御系统,加强与合作国在技术研发、联合防空和导弹防御等方面的合作,以提升地区防御力和威慑力。     

基于专利分析的富锂锰基正极材料应用趋势

使用PatSnap平台对全球富锂锰基正极材料相关领域的专利进行检索收集、查全、查重处理后得到分析样本,对样本进行整体概况分析、专利权人及发明人分析、技术分析,得到专利地图及专利高频关键词,剖析全球富锂锰基正极材料相关领域的发展现状和研究进展,对技术发展趋势进行预测。研究对我国高能量密度正极材料应用领域技术创新及专利策略具有重要意义。     

非晶合金材料发展趋势及启示

金属材料的发展与人类文明和进步息息相关。非晶合金材料是一类原子结构长程无序,具有独特优异性能的新型金属材料。近年来,非晶合金材料的研发、相关科学问题的研究、在高新技术领域的应用得到快速发展,并对金属材料的设计和研发、结构材料、绿色节能材料、磁性材料、催化材料、信息材料等领域产生深刻的影响。为此,文章在回顾非晶合金材料研究和研发历史过程的基础上,分析了当前其学科的前沿科学问题、发展方向,以及我国在该领域发展的问题、机遇和挑战,并提出相应的启示和建议,以期为加快新金属材料的发展,特别是在高新技术领域的应用提供管窥之见。