双重引发POE官能化及其增韧PA66的研究

采用双螺杆加工过程中的机械力引发同时添加引发剂的双重引发方法,研究了引发剂的用量、螺杆转速和接枝反应温度对马来酸酐接枝POE产物的接枝率、熔融指数的影响.对单纯采用引发剂引发方法和引发剂与机械力双重引发方法所得接枝产物增韧PA66的效果也进行了比较.     

尼龙6/POE/粘土纳米复合材料的形态、结构及性能研究

采用熔融方法制备了PA 6/POE/粘土纳米复合材料.PA 6/POE/粘土纳米复合材料具有良好的力学性能,其缺口冲击强度比PA 6有显著提高.研究结果表明,有机粘土剥离于PA 6基体中,POE相以岛状结构均匀分散于PA 6基体中;PA 6/POE/粘土纳米复合材料的储能模量比PA 6的低,并且随着有机粘土含量的增加而降低.PA 6/POE/粘土纳米复合材料的玻璃化转变温度(Tg)随着粘土含量的增加而升高,具有良好的热稳定性.     

一种新的分数阶记忆多项式预失真器

该文针对由记忆多项式设计的功率放大器预失真系统,提出了一种新的分数阶记忆多项式预失真器。提出预失真多项式是在常用记忆多项式基础上,通过去掉偶数阶项增加分数阶项以提高线性化性能。文中给出了分数阶记忆多项式的表达式,并给出了相应的系数估计算法。仿真分析表明,针对Wiener-Hammerstein和记忆多项式模型的功率放大器,在两种典型记忆多项式预失真的基础上可以分别得到10 dB和8 dB的带外谱抑制增益。相应的FPGA实现表明该预失真多项式总体硬件资源增加的代价并不高,易于在实际系统中应用。     

从新型聚酰胺树脂PA9T的开发看树脂品种牌号的创新

耐热性聚酰胺树脂ＰＡ９Ｔ的开发源于市场的需求,开发从大分子设计着手,得到配套基础化学品技术的支撑。为提高产品的创新能力,建议从切实加强市场调查,重视基础研究入手。     

细旦锦纶66弹力丝生产工艺探讨

介绍了16dtex／5f锦纶66弹力丝的生产设备、所用原料及工艺参数,着重介绍了纺丝工艺及后拉伸加弹工艺的控制。     

黑色锦纶6POY纺丝工艺

介绍了在进口锦纶高速纺生产线上生产４０ ｄｔｅｘ／１０ｆ 黑色锦纶６ ＰＯＹ 的生产工艺,并对切片及色母粒质量、纺丝温度、熔体过滤、侧吹风、上油、卷绕工艺进行讨论。     

CsCDPK6, a CsSAMS1-Interacting Protein,Affects Polyamine/Ethylene Biosynthesis in Cucumber and Enhances Salt Tolerance by Overexpression in Tobacco

S-adenosylmethionine synthetase (SAMS) plays a crucial role in regulating stress responses. In a recent study, we found that overexpression of the cucumber gene CsSAMS1 in tobacco can affect the production of polyamines and ethylene, as well as enhancing the salt stress tolerance of tobacco, but the exact underlying mechanisms are elusive. The calcium-dependent protein kinase (CDPK) family is ubiquitous in plants and performs different biological functions in plant development and response to abiotic stress. We used a yeast two-hybrid system to detect whether the protein CDPK6 could interact with SAMS1 and verified their interaction by bimolecular fluorescence complementation (BiFC) and co-immunoprecipitation (Co-IP) assays. To further explore the function of cucumber CDPK6, we isolated and characterized CsCDPK6 in cucumber. CsCDPK6 is a membrane protein that is highly expressed under various abiotic stresses, including salt stress. It was also observed that ectopic overexpression of CsCDPK6 in tobacco enhanced salt tolerance. Under salt stress, CsCDPK6-overexpressing lines enhanced the survival rate and reduced stomatal apertures in comparison to wild-type (WT) lines, as well as lowering malondialdehyde (MDA) and hydrogen peroxide (H₂O₂) contents and causing less relative electrolyte leakage. Moreover, repression of CsCDPK6 expression by virus-induced gene silencing (VIGS) in cucumber seedling cotyledons under salt stress increased ethylene production and promoted the transformation from putrescine (Put) to spermidine (Spd) and spermine (Spm). These findings shed light on the interaction of CsSAMS1 and CsCDPK6, which functions positively to regulate salt stress in plants.     

Toughening PA1010 with a functionalized saturated polyolefin elastomer

Polyamide (PA)1010 is blended with a saturated polyolefin elastomer, ethylene‐α‐olefin copolymer (EOCP). To improve the compatibility of PA1010 with EOCP, different grafting rates of EOCP with maleic anhydride (MA) are used. The reaction between PA1010 and EOCP‐g‐MA during extrusion is verified through an extraction test. Mechanical properties, such as notched Izod impact strength, elongation at break, etc., are examined as a function of grafting rate and weight fraction of elastomer. It was found that in the scale of grafting rate (0.13–0.92 wt %), 0.51 wt % is an extreme point for several mechanical properties. Elastomer domains of PA1010/EOCP‐g‐MA blends show a finer and more uniform dispersion in the matrix than that of PA1010/EOCP blends. For the same grafting rate, the average sizes of elastomer particles are almost independent on the contents of elastomer, but for different grafting rates, the particle sizes are decreased with increasing grafting rate. The copolymer formed during extrusion strengthens the interfacial adhesion and acts as an emulsifier to prevent the aggregation of elastomer in the process of blending. © 2000 John Wiley & Sons, Inc. J Appl Polym Sci 77: 928–933, 2000     

SFZ7-31500/66型变压器缺陷分析及事故防范措施

通过对浦东变2号主变压器烧损后的检测和油、气样色谱分析,确定了变压器故障类型为内部高温放电。该故障变压器经解体检查,发现设计及制造工艺均存在缺陷。鉴于系统内有多台同型号变压器仍在运行,为防止发生类似事故,提出加强变压器绕组变形测试、有针对性调整变压器运行规程等4项事故防范措施。     

聚丙烯接枝物反应挤出增容PP/PA6共混物的形态结构

采有PP熔融接枝MAH和不饱和羧酸混合单体通过反应挤出增容PP/PA6共混物，研究了增容共混物的形态结构。SEM、TEM观察表明，接枝物能明显降低共混物的分散相尺寸，改善体系的分散状况，提高共混物两相的相容性；增容共混物的两相界面结合改善，相界面变得模糊。WAXD、DSC测试表明，用该接枝物增容后的共混物，组分的Xc下降，分散相微晶尺才减小。研究结果表明该接枝物是PP/PA6共混体系的有效增容剂。