Studies on grafting of acrylic acid onto polypropylene melt‐blown nonwovens induced by electron‐beam preirradiation

We report the graft copolymerization of acrylic acid onto the polypropylene (PP) melt‐blown nonwovens induced by electron beam (EB) preirradiation in this article. The occurrence of the graft copolymerization was confirmed by means of XPS, FTIR, and SEM. The effects of preirradiation dose, monomer concentration, bath ratio, reaction time, and temperature on the graft ratio were investigated. The water conservation, water absorption rate, and K⁺ exchange capacity were also determined on the grafted PP melt‐blown nonwovens, which showed that EB preirradiation‐induced grafting was an effective way to improve the hydrophicility of PP melt‐blown nonwovens. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 102: 4971–4977, 2006     

基于逐次散射法的海洋-大气矢量辐射传输模式

首先推导了粗糙洋面双向偏振反射模型pBRDF(Bidirectional Polarized Reflectance Distribution Function),并将其与SOSVRT(Successive Order of Scattering Radiative Transfer)矢量辐射传输模式耦合,建立了海洋-大气耦合的矢量辐射传输模式,并对该耦合模式的模拟结果与前人模拟结果进行对比,验证了该耦合模式的可靠性与有效性。不同大气和洋面状态、不同高度的主平面内辐射强度和偏振度的模拟结果表明:pBRDF模型可以很好地模拟不同风速下洋面的偏振反射分布特征;洋面在特定角度具有很高的偏振度,并对大气顶的偏振辐射有很大影响。因此,该耦合模式可以更准确地处理辐射光谱在海洋-大气两种介质间的传输问题,对矢量辐射传输、大气遥感问题的研究有重要意义。     

浅谈多媒体教学以信息管理中心为例

高职教育的特点就是以适应社会需要为目标、以培养技术应用能力为主线设计学生的知识、能力、素质结构和培养方案,毕业生应具有基础理论知识适度、技术应用能力强、知识面较宽、素质高等特点.以“应用”为主旨来构建课程和教学内容体系.     

乙烯二聚制高纯丁烯－1技术经济评价

本文对生产高纯度丁烯－１的Ａｌｐｈａｂｎｔｏｌ工艺进行了技术经济评价，认为该工艺条件简单、反应条件温和，而且投资少，所以很适合事在发展中国家应用。     

Effect of structural and electrochemical properties of different Cr-doped contents of Li[Ni1/3Mn1/3Co1/3]O2

Layered Li[Ni_(1−x)/3Mn_(1−x)/3Co_(1−x)/3Cr_x]O₂ materials with x = 0, 0.01, 0.02, 0.03, 0.05 are prepared by a solid-state pyrolysis method. The oxide compounds were calcined with various Cr-doped contents, which result in greater difference in morphological (shape, particle size and specific surface area) and the electrochemical (first charge profile, reversible capacity and rate capability) differences. The Li[Ni_(1−x)/3Mn_(1−x)/3Co_(1−x)/3Cr_x]O₂ powders were characterized by means of X-ray diffraction (XRD), charge/discharge cycling, cyclic voltammetry, and SEM. XRD experiment revealed that the Li[Ni_(1−x)/3Mn_(1−x)/3Co_(1−x)/3Cr_x]O₂ (x = 0, 0.01, 0.02, 0.03, 0.05) were crystallized to well layered -NaFeO₂ structure. The first specific discharge capacity and coulombic efficiency of the electrode of Cr-doped materials were higher than that of pristine material. When x = 0.02, the sample showed the highest first discharge capacity of 241.9 mAh g⁻¹ at a current density of 30 mA g⁻¹ in the voltage range 2.3–4.6 V, and the Cr-doped samples exhibited higher discharge capacity and better cycleability under medium and high current densities at room temperature.     

孤岛油田馆陶组湖相沉积认识及应用

济阳拗陷新近系馆陶组普遍发育河流相的观念由来已久,研究中重点通过连续取芯井的岩芯观察,以及综合利用录井、测井、古生物及相关分析化验资料,运用沉积学理论,丰富和发展了原有孤岛油田馆陶组仅仅普遍发育河流相的沉积观点,认为馆陶组下段不仅发育砾质辫状河沉积,还发育辫状河三角洲-充填型浅水湖泊沉积体系;馆陶组上段初期发育辫状河、曲流河等河流相沉积,中晚期发育浅水三角洲-氧化型浅水湖泊以及浅水振荡湖泊沉积体系.湖相沉积模式在与油田生产密切相关的小层对比和油气勘探中的应用广泛.     

基于STC单片机的焊接摆动器控制系统的设计

介绍了基于STC单片机焊接摆动器控制系统的设计,包括电源模块、单片机控制模块、直流电机脉宽调制(PWM)调速模块、红外线二极管检测与放大电路模块、人机交互模块等系统硬件设计,以及用C语言实现的系统软件设计.该系统能够控制焊枪以特定的预置参数进行摆动并配合一台小车进行流水线操作,从而达到自动焊接过程中的特殊要求.通过现场运行,系统稳定,可靠性高,满足工业现场要求.     

基于模拟退火的AVO无井约束反演

AVO(振幅随入射角变化)反演是一个非线性的组合最优化过程,运用弹性介质模型参数正演生成合成记录,以拟合观测数据。对于没有井资料的地区,结合勘探区域的地质情况对地震数据进行反演,最终得到勘探区域岩石物性参数。采用模拟退火算法进行AVO无井约束反演,对理论模型进行了试算,证明了模拟退火算法在AVO无井约束反演中的可行性。在模拟退火过程中,控制参数选择是重要的一步,要针对所要处理数据进行试验来确定这些参数的合理范围,如果参数选择不当,容易陷入局部极值,得到不理想的结果。     

发展低碳经济对旅游业的要求和影响

阐述了低碳经济和低碳旅游的内涵,认为旅游业作为低污染行业,可在发展低碳经济方面起到引领和示范的作用。分析了低碳经济对旅游主体、旅游客体、旅游媒体的影响。     

基于MATLAB/Simulink的染料敏化太阳能电池输出特性仿真

根据染料敏化太阳能电池(DSSC)的等效电路,应用MATLAB/Simulink工具建立仿真模型,对DSSC的输出伏安特性及输出功率进行仿真,讨论串联电阻和分流电阻对DSSC性能的影响.仿真结果表明,随着串联电阻的增加,开路电压不变,短路电流密度、最大输出功率及填充因子降低;随着分流电阻的增加,开路电压、短路电流密度、...