Head-to-head polymers: 33. Bromination of cis-1,4-polybutadiene to head-to-head poly(vinyl bromide)

Cis-1,4-polybutadiene (PB) in a 0.5% solution of a solvent mixture of dichloromethane and 1,2-dibromoethane or tetrahydrofuran was quantitatively brominated with elemental bromine at 0°C under careful exclusion of oxygen to head-to-head poly(vinyl bromide). Partially brominated PB has a structure of random or block sequences of butadiene units in the polymer depending on the bromination solvent but shows no stereospecificity in the CHBrCHBr-dyads. Partially brominated PB with block structure showed a microphase-separated morphology over a wide range of composition. Microphase separation is less pronounced for the more random structure of butadiene units. I.r and ¹³C n.m.r. spectroscopy of the partially brominated PB was used to follow the progress of the bromination.     

基于剪切带扩展法的海底斜坡稳定性分析

简介剪切带扩展法（SBP）的原理及其在海底滑坡稳定性分析的应用;以舟山六横岛典型海底斜坡为分析案例,开展基于高斯函数的SBP和极限平衡法（LEM）斜坡稳定性对比分析研究;进行SBP输入参数对剪切带扩展系数R的敏感度分析. 研究结果显示,对于斜坡剪切带破坏长度,当剪切带扩展系数R不大于1时,LEM与SBP得到的滑坡滑裂面区域一致,当R大于1时,SBP计算得到的最终滑动区域比LEM计算得到的区域大;在斜坡发生滑动破坏区域SBP比LEM计算得到的安全系数低;地震影响因素和土体特征位移对R的影响较大.     

响应面分析法优化山楂叶中黄酮的提取工艺

响应面分析法优化山楂叶中黄酮的提取工艺,以黄酮粗提取率为指标,采用乙醇回流法提取。通过单因素试验及响应面分析,研究了提取温度、液固比、乙醇体积分数和提取时间4个主要因素对山楂叶中黄酮粗提取率的影响。采用Box-Behnken中心组合设计和响应面分析法,建立了回归方程的预测模型,确定最佳提取条件为液固比29 mL/g ,乙醇体积分数68％,提取温度64℃,提取时间34 min ,在此条件下黄酮粗提取率为3．07％。试验结果与模型预测值基本相符,因此,该工艺可应用于山楂叶中黄酮的提取。     

Solid Ink Laser Patterning for High-Resolution Information Labels with Supervised Learning Readout

Tagging, tracking, or validation of products are often facilitated by inkjet-printed optical information labels. However, this requires thorough substrate pretreatment, ink optimization, and often lacks in printing precision/resolution. Herein, a printing method based on laser-driven deposition of solid polymer ink that allows for printing on various substrates without pretreatment is demonstrated. Since the deposition process has a precision of <1 µm, it can introduce the concept of sub-positions with overlapping spots. This enables high-resolution fluorescent labels with comparable spot-to-spot distance of down to 15 µm (444,444 spots cm⁻²) and rapid machine learning-supported readout based on low-resolution fluorescence imaging. Furthermore, the defined thickness of the printed polymer ink spots can be used to fabricate multi-channel information labels. Additional information can be stored in different fluorescence channels or in a hidden topography channel of the label that is independent of the fluorescence.     

化学反应速率的计算机数据登录及处理系统

介绍一种计算机数据登录及处理系统，主要用于测定忆醇乙酯皂化反应速率常数的实验。     

异地计算机教学与训练系统的结构模型研究

异地计算机教学与训练系统就是利用计算机网络环境，向分布在异地的授课者和学习者提供一种模拟面对面教学和训练的虚拟环境。     

单片机在洗衣机偏心检测中的应用

介绍了利用MC68HC908AB32单片机对滚筒洗衣机衣物偏心量进行检测的方法。详细说明了硬件组成和工作原理，举例分析了有关程序。     

"抢渡长江"问题数学建模及求解分析

对“抢渡长江”问题进行了分析，建立了一种函数极值的数学模型，分析了解题思路和初等求解方法．     

计及LCA碳排放的源荷双侧合作博弈调度研究

为实现新型电力系统的低碳经济目标,提出一种计及生命周期评价(lifecycleassessment, LCA)的源荷双侧合作博弈优化调度模型。首先,考虑灵活可调度的柔性负荷,构建含热电联产机组、燃气锅炉、电转气等设备的源荷双侧合作运行框架。然后,运用LCA方法分析源荷双侧中不同能源链的温室气体排放,并结合碳交易机制,建立碳交易成本计算模型。最后,基于合作博弈策略,建立以源荷合作联盟总成本最小为目标的源荷双侧协同运行优化模型,并利用改进的Shapley值法对成员合作收益进行分配。算例分析表明,所提模型有利于降低系统运行的总成本、减少系统碳排放量、提升可再生能源消纳量,有效促进系统低碳经济的发展。