One‐Dimensional Assemblies of Nanoparticles: Preparation,Properties, and Promise

Nanoparticle (NP) assemblies are of considerable interest for both fundamental research and applications, since they provide direct bridges between nanometer‐scale objects and the macroscale world. Unlike two‐dimensional or three‐dimensional NP assemblies, which have been extensively studied and reviewed, reports on one‐dimensional (1D) NP assemblies are rather rare, even though these assemblies are likely to play critical roles in the improvement of the efficiencies of various electronic, optoelectronic, magnetic, and other devices based on single NPs or their composites. Additionally, 1D assemblies of NPs, i.e., chains, can significantly help in the understanding of a number of biological processes and fundamental quantum mechanics of nanometer‐scale systems. The difficulties are very evident when one wants to realize anisotropic 1D assemblies from presumably isotropic, zero‐dimensional NPs. In this context, the authors present a systemic review of current research on 1D NP assemblies. Their preparation methods are classified and novel characteristics of NP chains, such as collective properties and directional transfer of photons, electrons, spins, etc., are elucidated. Current problems underlying the fundamental research and practical applications of 1D NP assemblies are also addressed.     

纯棉沙滩巾酶氧连续汽蒸退煮漂工艺

通过采用生物酶制剂和正交试验方法，研制出纯棉沙滩巾酶氧连续汽蒸退煮漂一步法绿色加工工艺，从而有效地去除了棉纤维中的天然杂质及织造过程中的浆料等，达到了提高产品质量。缩短生产工序，降低生产成本，减少环境污染的目的。     

英语替代词One的用法探析

英语中的替代是一种避免重复，连接上下文的语法手段。许多词汇可用替代词来替代，而且有些词汇可用作替代词，其中one是用法最多，也是最难把握的。     

基于OTP的移动商务环境下的一种身份认证方案

该文在现有身份认证技术的基础上,基于一次性口令(OTP)认证技术,提出了移动商务环境下的一种身份认证方案。与传统方案相比,该方案考虑了移动商务的安全性要求及移动设备的技术限制,引入服务提供次数作为不确定因素,安全性高,运算量小,实现了通信双方的相互认证。     

Hybrid recommendations for mobile commerce based on mobile phone features

Mobile data communications have evolved as the number of third generation (3G) subscribers has increased. The evolution has triggered an increase in the use of mobile devices, such as mobile phones, to conduct mobile commerce and mobile shopping on the mobile web. There are fewer products to browse on the mobile web; hence, one‐to‐one marketing with product recommendations is important. Typical collaborative filtering (CF) recommendation systems make recommendations to potential customers based on the purchase behaviour of customers with similar preferences. However, this method may suffer from the so‐called sparsity problem, which means there may not be sufficient similar users because the user‐item rating matrix is sparse. In mobile shopping environments, the features of users' mobile phones provide different functionalities for using mobile services; thus, the features may be used to identify users with similar purchase behaviour. In this paper, we propose a mobile phone feature (MPF)‐based hybrid method to resolve the sparsity issue of the typical CF method in mobile environments. We use the features of mobile phones to identify users' characteristics and then cluster users into groups with similar interests. The hybrid method combines the MPF‐based method and a preference‐based method that uses association rule mining to extract recommendation rules from user groups and make recommendations. Our experiment results show that the proposed hybrid method performs better than other recommendation methods.     

一遍完成的平衡布点外存模型简化算法

现存的自适应采样的外存模型简化算法均需要多次读取原模型，算法效率较低。该文给出一种仅仅需要读取原模型一遍的自适应顶点聚类算法－平衡布点算法（Balanced Tilling,BT），用于外存模型简化。其关键思想在于通过表面编码记录模型表面，通过对原模型的二次量化（quadric quantization）得到原模型上的细节分布。该算法可以定位出所有类型的细节区域，而其它一些算法只能定位细节边。细节区域将被进一步细化，而平滑区域将被进一步简化。该算法大大减少了输入输出时间，尤其适合处理超大规模模型。内存需求很小，只与输出模型规模有关。     

轴流涡轮与排气壳扩压段一维耦合设计研究

为探究轴流涡轮耦合排气壳扩压段的一维设计变量选取规律,提高排气壳扩压段的性能,参考现有NRCC叶栅导叶模型,采用自编程序,结合理论分析构建轴流涡轮与排气扩压段耦合的一维设计模型。详细分析耦合设计中影响扩压段的静压恢复系数以及总体性能的因素。研究结果表明：扩压段面积比、平均倾角、扩张角以及壁面摩擦系数等设计参数不仅影响扩压段的静压恢复系数,也影响涡轮的气动效率;本研究模型在面积比为3.5、平均倾角为30°、扩张角δ为5°时整体性能最优;涡轮出口气流的马赫数、叶顶泄漏流以及出口旋流对扩压段的性能有很大影响,出口半径比的增大会使得静压恢复系数降低,因此在耦合设计时应充分考虑涡轮以上参数的选择。     

一维纳米碳在碳基体上生长的研究进展

综述了采用化学气相沉积法在各种碳质基体上生长一维纳米碳的制备方法,阐述了基体的预处理、催化剂、碳源、生长温度等各种因素对产物的影响,简要介绍了在碳基体上生长一维纳米碳的性能和应用.     

情感美学观在魏晋六朝时期文人画与理论作品中的体现

魏晋南北朝时中国传统情感美学观正式形成,对中国美学有着里程碑的纪念意义,对其后世的艺术发展起着深远的影响作用。本文通过对魏晋南北朝绘画作品的品读来体会这个时期画家们纵情任性的审美观。     

基于混合特征的人体动作识别改进算法

运动特征的选择直接影响人体动作识别方法的识别效果.单一特征往往受到人体外观、环境、摄像机设置等因素的影响不同,其适用范围不同,识别效果也是有限的.在研究人体动作的表征与识别的基础上,充分考虑不同特征的优缺点,提出一种结合全局的剪影特征和局部的光流特征的混合特征,并用于人体动作识别.实验结果表明,该算法得到了理想的识别结果,对于Weizmann数据库中的动作可以达到100％的正确识别率.