Application of Co3O4-based materials in electrocatalytic hydrogen evolution reaction: A review

Environmental pollution and energy shortage make the development of clean energy more and more urgent. As a kind of clean renewable energy, hydrogen have attracted great attentions in recent years. Recently, Co₃O₄-based materials have emerged as promising candidates for electrocatalytic hydrogen evolution reaction (HER), due to their attractive electrocatalytic activity, low cost as well as the electrochemical durability, which make it attract widely attentions. In this review, we summarize the application of Co₃O₄-based materials in electrocatalytic HER, including pure Co₃O₄, the doped Co₃O₄ and the Co₃O₄-based composite materials. Furthermore, the strategies to enhance their electrocatalytic performance are summarized and discussed, such as morphological engineering, doping, as well as compositing with other materials. Finally, the limitation and challenges of Co₃O₄-based materials for HER, as well as their prospects for future research, are proposed. We believe that this review will be helpful for scientists to seek promising HER electrocatalytic materials.     

Synthesis and properties of block and graft waterborne polyurethane modified with α,ω‐bis(3‐(1‐methoxy‐2‐hydroxypropoxy)propyl)polydimethylsiloxane and α‐N,N‐dihydroxyethylaminopropyl‐ω‐butylpolydimethylsiloxane

In this study, α,ω‐bis(3‐(1‐methoxy‐2‐hydroxypropoxy)propyl)polydimethylsiloxane and α‐N,N‐dihydroxyethylaminopropyl‐ω‐butylpolydimethylsiloxane were used to prepare block and graft waterborne polyureathane–polysiloxane copolymer dispersions. α,ω‐bis(3‐(1‐methoxy‐2‐hydroxypropoxy)propyl)polydimethylsiloxane was synthesized by hydrosilylation, methoxylation and equilibrium reactions; α‐N,N‐dihydroxyethylaminopropyl‐ω‐butylpolydimethylsiloxane was synthesized via hydroxyl protection, alkylation, anionic ring‐opening polymerization, hydrosilylation, and deprotection. Block and graft waterborne polyurethane–polysiloxane copolymer dispersions were prepared by the reaction of poly(propylene glycol) (PPG), toluene diisocyanate (TDI), 2,2‐dimethylol propionic acid (DMPA), 1,4‐butanediol (BDO), α,ω‐bis(3‐(1‐methoxy‐2‐hydroxypropoxy)propyl)polydimethylsiloxane, and α‐N,N‐dihydroxy‐ethylaminopropyl‐ω‐butylpolydimethylsiloxane. The water absorption of block and graft waterborne polyurethane–polysiloxane copolymer films decreased from 163.9 to 40.2% and 17.3%, respectively, when percent of polysiloxane (w/w) increased from 0 to 5%, and the tensile strength of the block waterborne polyurethane–polysiloxane copolymer films decreased while the tensile strength of graft waterborne polyurethane–polysiloxane copolymer films increased with increase of percent of polysiloxane. For graft waterborne polyurethane–polysiloxane films, the tensile strength would decrease when percent of polysiloxane was more than 3%. POLYM. ENG. SCI., 54:805–811, 2014. © 2013 Society of Plastics Engineers     

儿童实体交互叙事系统的游戏化设计策略研究

游戏是儿童玩耍天性的直接体现。游戏既可以吸引儿童参与活动,还能够促使儿童在活动中开展合作。因此,本研究尝试将游戏元素引入儿童实体交互叙事系统,以丰富儿童“讲故事”的行为和过程。引入游戏设计中的MDA(Mechanics,Dynamics,Aesthetics)游戏化结构模型,为儿童实体交互叙事系统提供设计策略与指导,并将游戏元素、游戏机制和游戏体验这3个关键模块代入面向儿童的实体交互叙事系统中。通过MDA游戏化结构模型对系统建构的指导,分析相关研究案例,提出儿童实体交互叙事系统中的游戏化设计策略。     

Comparison of three-dimensional reconstruction approaches for anthropometry in apparel design

The anthropometry is the fundamental knowledge for apparel design. While quite a few techniques have been developed for this purpose, it also becomes an obstacle for conducting a customized apparel design. Not only because most of them are expensive but they are also not quite clarified in their accuracy, speed, implement, and complexity. This article investigates three existing anthropometric approaches including two-dimensional–three-dimensional (2D-3D) mapping, point-cloud approach, and dense-reconstruction approach. With conducting three experiments in terms of these approaches, 3D reconstructive model have been built and then used for anthropometry. The results in this study have addressed the aforementioned issues; in particular, the accuracy and reliability of the anthropometric measurements built on these three approaches have been clarified. There are two main contributions out from this study. The first one is the provision of several references for users or customers to select anthropometric approaches in different apparel design scenarios. The second one is the provision of the fundamental knowledge of anthropometry for the development of conducting a customized apparel design online.     

基于设计奖项获奖案例的设计知识建模研究

为实现设计奖项获奖案例中的优秀设计知识的有效重用,对获奖案例中的设计知识类别和表示方式进行研究。通过分析设计奖项获奖案例中的设计知识内涵;引入本体概念,根据本体的四元组模型构建获奖案例中设计知识的本体结构。以中国设计智造大奖(DIA)中智慧城市服务平台类获奖案例为例,通过语言逻辑学、语义研究等方法对获奖案例的设计知识进行概念、本体属性、概念关系的描述和定义,从而搭建设计奖项知识(DAK)模型,并借助OWL语言和知识图谱等方式实现智慧城市服务平台类获奖案例中设计知识的语义表示。提出一种基于本体的设计奖项获奖案例知识模型,为设计奖项中的优秀设计知识储存、管理、重用提供理论支持和实践参考。     

基于机器视觉的柔性包装袋喷码缺陷检测研究

目的 针对传统喷码检测方法计算量大、字符区域定位不显著、识别准确率较低等不足,提出一种基于机器视觉的柔性包装袋喷码缺陷检测方法。方法 以柔性包装袋上喷码图像为研究对象,以滤波抑噪、阈值处理等技术对图像进行预处理,运用YOLO-V3网络模型对字符区域进行定位,并采用阈值和非极大值抑制算法提高喷码区域定位的显著性,通过改进AlexNet网络结构、运用多特征融合运算等方法,获取更为丰富的图像卷积特征,实现字符串的整体识别,从而提高喷码缺陷识别的准确率。结果 将YOLO-V3联合改进AlexNet的检测方法与传统喷码检测方法进行对比,结果表明,所设计喷码缺陷检测方法的分类准确率达到99.39%。结论 基于机器视觉的柔性包装袋喷码缺陷检测方法在模型计算量、字符区域定位显著性和字符识别准确率都有一定的优势,并有效解决了字符串整体识别的问题。     

融入新媒体技术的视觉传达设计

目的 探究新媒体技术的发展给视觉传达设计所带来的机遇与挑战,并从融合视角深入挖掘两者的相关性及具体的发展路径。方法 以新媒体艺术的产生为背景,探讨其给人们的生活所带来的全新体验和巨大变化,借此引出新媒体艺术对视觉传达设计的重要作用及影响,接着以新媒体中视觉传达设计的情感性、互动性、多维性特征为基点,分析新媒体艺术与视觉传达设计融合的必要性和未来发展趋势,最后分别从广告设计、标志设计逐一展开深入细致的分析,探究新媒体技术与视觉传达设计的具体结合方式。结论 新媒体依靠新的科技成果结合数字技术给视觉传达设计带来了新的发展机遇,其所呈现的艺术设计效果达到了传统设计无法实现的艺术效果,既给受众带来了高品质的视觉、感官享受,又以此为支撑,有效带动了整个媒体艺术产业的健康发展。     

High-pressure xenon detector development at Constellation Technology Corporation

Xenon-filled ionization detectors, due to their high atomic number fill gas (Z=54), moderate densities (∼0.3–0.5 g/cm³) and good energy resolution (2–4% at 662 keV), fill an important niche between more familiar technologies such as NaI(Tl) scintillators and germanium detectors. Until recently, difficulties with obtaining sufficient xenon purity, reducing microphonic sensitivity, and developing low-noise electronics compatible with small ionization signals have hampered the development of this nuclear detection field. Constellation Technology Corporation, whose experience with xenon detectors goes back to the mid 1990s, has made significant progress in these areas and has developed a commercial line of detectors with active volumes ranging from small (35 g Xe) to large (1400 g Xe). Current applications for Constellation's detectors are principally in the area of defense (Unmanned Aerial Vehicles and Advanced Spectroscopic Portals), but as awareness of this technology grows, it will surely find applications in a much expanded range of fields.     

A comparative study of tactile paving design standards in different countries

Tactile paving is a system of textured ground surface indicators found on public environments to assist blind and visually impaired persons to distinguish locations and directions, identify potential hazards, and then to move and reach expected destinations. The design of tactile paving is different from those of many public facilities because tactile paving is mainly used by blind and visually impaired persons. Although tactile paving was invented several decades ago it is only recently that it has been widely implemented in many cities, yet criticism on its unsatisfactory design for its particular users as well as other people is still frequently heard. One of the critical comments is the lack of a good standard. This paper reviews the history and development of tactile paving. By reviewing particular characteristics of tactile paving and the needs of blind and visually impaired persons, this paper discusses the importance of a standard for tactile paving. This paper then compares different tactile paving design standards in several selected countries. Focusing on the factors of type, pattern and color in constituting the standards of tactile paving, this paper tries to identify the problems of tactile paving in China, and then gives some suggestions and insights for consideration and further investigation.