An ergonomics study of thumb movements on smartphone touch screen

This study investigated the relationships between thumb muscle activity and thumb operating tasks on a smartphone touch screen with one-hand posture. Six muscles in the right thumb and forearm were targeted in this study, namely adductor pollicis, flexor pollicis brevis, abductor pollicis brevis (APB), abductor pollicis longus, first dorsal interosseous (FDI) and extensor digitorum. The performance measures showed that the thumb developed fatigue rapidly when tapping on smaller buttons (diameter: 9 mm compared with 3 mm), and moved more slowly in flexion–extension than in adduction–abduction orientation. Meanwhile, the electromyography and perceived exertion values of FDI significantly increased in small button and flexion–extension tasks, while those of APB were greater in the adduction–abduction task. This study reveals that muscle effort among thumb muscles on a touch screen smartphone varies according to the task, and suggests that the use of small touch buttons should be minimised for better thumb performance.     

皂化膜萃取法制备环烷酸钕的研究

提出了一种在室温条件下 ,皂化膜萃取法合成稀土橡胶主催化剂环烷酸钕的新工艺 ,并对其影响因素和反应机理进行了研究。采用皂化萃取工艺 ,可提高Nd3 +的利用率 ,并可根据皂化率任意控制游离酸浓度。采用膜萃取工艺可减少环烷酸钕中的含水量 ,制得的环烷酸钕具有良好的二烯烃定向聚合活性。     

Kinetic study of the curing behavior of bismaleimide modified with diallylbisphenol A

The curing kinetics of bismaleimide modified with diallylbisphenol A were investigated for different ratios of 1,1′‐(methylene di‐4,1‐phenylene) bismaleimide and diallylbisphenol A with differential scanning calorimetry. Multiheating‐rate and isothermal methods were used to study the kinetics of the curing process. The results indicated that the activation energy changed with the extent of conversion. The activation energy obtained by the multiheating‐rate method was higher than that obtained by the isothermal method. Two kinetic models (autocatalytic and nth‐order) were successfully used to model the curing process. © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 90: 2229–2240, 2003     

UHMWPE/LDPE复合材料拉伸破坏的声发射特性研究(Ⅱ)

本文续“UHMWPE/LDPE复合材料拉伸破坏的声发射特性研究(Ⅰ)”,进一步研究了UHMWPE/LDPE复合材料拉伸破坏的声发射特性,具体研究了[0°]、[90°]在拉伸破坏过程中声发射参数特征,并对拉伸破坏机理进行了初步的研究。     

Gemini表面活性剂的结构特点及在采油中的应用

文章简要地介绍了Gemini表面活性剂的结构特点；从表面活性剂的作用原理出发，介绍了Gemini表面活性剂的优良性能：如表面张力、泡沫力、润湿力、优异的协同效应、耐温抗盐性等；在此基础上，阐述了该类表面活性剂在油田三次采油上的应用前景。     

塔板结构参数对负荷性能曲线的影响

通过对板式塔流体力学性能的分析，找出了板式塔塔板结构参数对负荷性能图中负荷性能曲线的影响关系，可用于指导板式塔的优化设计和改造。     

水泥厂CDM项目开发

清洁发展机制（cDM）的开发，有利于发达国家温室气体减排任务的实现，又有利于发展中国家的技术进步。文章简要介绍了CDM的基本概念和申报CDM项目应满足的条件，重点介绍了水泥行业开发CDM项目的潜力及其相应的方法学和适用条件：同时还介绍了CDM的开发进程和效益分析。     

注射成型模具排气槽的设计

塑料注射成型模具的排气方式和排气槽结构直接影响塑料制品质量。介绍了塑料注射成型模具的排气方式、排气槽设计经验以及切实可行的排气方案和排气槽结构。     

Effect of Cr3C2 on Valence-Electron Structure and Plasticity of Rim Phase in Ti(C,N)-Based Cermets

Based on the empirical electron theory of solids and molecules, the valence-electron structure (VES) of the rim phase in Ti(C,N)-based cermets was calculated, and the relationship between the VES and plasticity was determined. The results indicated that the plasticity of the rim phase in a Ti(C,N)-based cermet could be defined using the sum of the n _a values for the covalent bonds, and that chromium dissolution in the rim phase improved the plasticity of the rim phase. Moreover, a series of experiments showed that adding Cr₂C₃ to a typical Ti(C,N)-based cermet strengthened the interface. Based on those results, a Ti(C,N)-based cermet with added Cr₃C₂ was manufactured; the new cermet had more than twice the transverse rupture strength of a typical cermet.