Encapsulation of disperse dye by phase separation technique using poly(styrene‐maleic acid)

C.I. disperse dye blue 60 was encapsulated by poly(styrene‐maleic acid) using phase separation technique, followed by the preparation of the encapsulated disperse dye dispersion. The effects of process conditions on particle size of the dispersion were investigated. The results showed that the particle size of the encapsulated disperse dye dispersion was small, and the stability was excellent when mass ratio of poly(styrene‐maleic acid) to disperse dye (R_p/d), dropping speed of phase separation agent (D_s), disperse dye content in dispersion (C_d), and dispersing time (D_t) were about 20%, 7 mL/min, 5–7.5%, and 1.5 h, respectively. Transmission electron microscope (TEM), zeta potentials, and contact angle indicated that C.I. disperse dye blue 60 was successfully encapsulated by poly(styrene‐maleic acid). © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2011     

Boron‐dependent microstructural evolution,thermal stability,and crystallization of mechanical alloying derived SiBCN

Amorphous boron‐rich SiBCN were prepared by high‐energy ball‐milling of the mixtures of Si, graphite, h‐BN, and inorganic boron, which acted as extra boron source. The solid‐state amorphization, thermal stability, and crystallization of the boron‐rich SiBCN were studied in detail. It was suggested that mechanical alloying can drive solid‐state amorphization but also can be an initiation step for the nucleation of nanocrystals. The amorphous networks of Si‐C, C‐B, C‐C, C‐N, B‐N, and C‐B‐N bonds are detected by XPS; however, solid‐state NMR further confirms the formation of a new chemical environment around B atoms, BC₃. The increases in boron content improve the thermal stability of SiBCN ceramics but weaken their oxidation resistance. Nano‐SiC crystallizes first while BN(C) forms subsequently. Boron promoting SiC crystallization may result from the reduced hindering effects of B‐N‐C nanodomains that retard SiC crystallization.     

氯丁橡胶244与天然胶共混性能研究

摘要:本文主要研究了硫化体系和补强体系对氯丁橡胶与天然胶共混时性能的影响,其中主要涉及到氧化锌、氧化镁、普通硫磺、DM作为硫化体系以及碳黑N550和白炭黑作为补强体系时对共混胶料物理机械性能的影响。经过研究发现：氧化锌：氧化镁：普通硫磺：DM硫化促进剂=6：3：5：0.3时,扯断强度能达到：23.18MPa,硫磺对硫化胶料绍尔硬度的影响最大,硫化时间为60min时得到的物理机械性能最好,碳黑N550为40份、白炭黑为20份时,硫化胶料的物理机械性能最好。     

超高分子量聚乙烯（UHMWPE）冻胶丝在拉伸初级阶段的结构演变

聚乙烯在白油中溶胀后形成半稀液,经双螺杆挤出机、纺丝箱等,通过凝胶纺丝技术获得冻胶丝,再经连续拉伸得到 UHMWPE 纤维。采用扫描电子显微镜（SEM）、小角和宽角 X 射线散射（SAXS 、WAXS）测试分析,建立了纤维在拉伸初级阶段结构演变过程的模型。结果表明,在 110 ℃（接近熔点的温度）连续拉伸,片晶向纤维晶转变的过程首先是拉伸诱导结晶的过程。随着拉伸持续,晶体被破坏,分子链被不断拉出晶体块并充分展开,最终形成伸直链纤维。     

交直流电压下油纸绝缘典型缺陷的局部放电特征

油纸绝缘局部放电问题受到业内普遍关注,为探究在交直流复合电压下的局部放电特征,该文搭建测量平台,并设计气隙、悬浮、柱板沿面和针板放电4种油纸绝缘典型缺陷的放电模型.结合这4种局部放电的实验结果,分析发现:在不同的复合电压比例下,4种典型缺陷局部放电会发生不同的变化,前3种缺陷平均放电量在起始阶段与直流分量呈现负向变化的...     

基于门控循环单元与误差修正的短期负荷预测

针对负荷预测模型迭代训练过程中存在误差积累的问题,提出结合叠式双向门控循环单元（SBiGRU）、完整自适应噪声集成经验模态分解（CEEMDAN）和误差修正的组合预测模型. 建立SBiGRU模型学习在气温、日期类型影响下负荷序列的时序特征,误差特征体现在SBiGRU模型预测产生的误差序列中;使用CEEMDAN算法将误差序列分解为数个本征模态函数（IMF）分量与趋势分量,对每项分量再次建立SBiGRU模型进行学习与预测,并对各分量的预测值进行序列重构,得到误差的预测结果;对预测结果进行求和以修正误差. 模型评估结果表明,组合模型的预测准确精度为98.86%,与SBiGRU、BiRNN、支持向量回归等方法相比,该模型具有更好的精度.     

求解一阶线性递推问题二分法的稳定性分析和误差估计

对求解一阶线性递推问题的串行算法和二分法进行了稳定性分析和误差估计，证明了串行算法与奇偶二分法，对半二分法和变间距二分法都是数值稳定的，并给出了这些算法的数值计算结果的误差估计。     

集值映射下向量优化的最优性条件

研究了赋范空间中具有相依导数和切导数的集值映射的最优化问题。建立了集值映射的约束资格，给出了问题（ＶＰ）具Ｋｕｈｎ－Ｔｕｃｋｅｒ的充分条件和必要条件。     

连铸矩形坯二次冷却水系统的工艺方案

以上钢三厂1#连铸机二次冷却系统改造为研究对象，应用连铸工艺理论，结合该厂多年实际生产经验研制了矩形坯连铸机二次冷却水系统的工艺方案，其中配水模式的确定、配水参数的处理充分体现出工程化的思想．经一年半的实际生产验证，本方案是成功的，给工厂带来了良好的经济效益．     

构件结构性能两套检验荷载的衔接

预制混凝土构件结构性能检验,要使试验检验的结论科学和准确,试验过程就必须严谨有序。为此,事先应有一个试验方案,预先对加载值作出严密的规划,结合本单位实际的试验条件,还应把检验内容的试验做法具体化,落实为一个完整的试验方案,也就是加载检验方案,以便在试验过程中有所遵循,避免出错。