Effects of the compatibilizer PP-g-GMA on morphology and mechanical properties of PP/PC blends

Effects of the compatibilizer polypropylene grafted with glycidyl methacrylate(PP-g-GMA) on the morphology, thermal, rheological and mechanical properties of polypropylene and polycarbonate blends (PP/PC) were studied. It was found that the addition of PP-g-GMA significantly changed their morphology. The mean size of domains reduced from 20 mu m to less than 5 mu m. The dispersed domain size is also strongly dependent upon the content of PP-g-GMA. The interfacial tension of PP/PC/PP-g-GMA (50/30/20) is only about one-tenth of PP/PC (70/30). The crystallization temperature of PP in PP/PC/PP-g-GMA is 5-8 degrees C higher than that of PP in PP/PC blends. Characterization studies based on mechanical properties, differential scanning calorimetry, rheology and morphological evidence obtained by using scanning electron microscopy support the hypothesis that an in-situ copolymer PP-g-PC was formed during the blending process. (C) 1997 Elsevier Science Ltd.

高耐热型系列ABS/PC合金的研制及其应用

介绍了高耐热型、高耐热高抗冲击型及高耐热阻燃型ABS/PC合金的研制和应用。

高耐热型系列ABS/PC合金的研制

介绍了高耐热型、高耐热高抗冲击型及高耐热阻燃型ABS/PC合金的研制和应用。

含核－壳聚合物共混体系PC／PBA－cs－PMMA的研究

将聚碳酸酯（ＰＣ）和聚丙烯酸丁酯－聚甲基丙烯酸甲酯核－壳聚合物（ＰＢＡ－ｃｓ－ＰＭＭＡ），采用密炼机以不同条件机械混合。经力学性能测试、形态结构观察和转变行为表征表明，ＰＣ与ＰＭＭＡ具有一定的相容性，ＰＢＡ－ｃｓ－ＰＭＭＡ能很好地分散在ＰＣ中，当其含量超过１０％，共混物的冲击强度值为ＰＣ的１０余倍，是ＰＣ的良好增韧剂。增韧机理属银纹和剪切屈服共存。

PES／PC共混体系的相容性与力学性能

ＰＥＳ／ＰＣ共混体系的相容性与力学性能姜振华，马荣堂，寇喜春，安立佳（吉林大学化学系长春）（中国科学院长春应用化学研究所长春１３００２２）关键词聚醚砜，聚碳酸酯，共混物，力学性能聚醚砜（ＰＥＳ）是一种性能优异的特种工程塑料，它具有强度高、刚性大、耐热...

ALGORITHM FOR COMPUTER PERCEPTION OF TOPOLOGICAL SYMMETRY

For the exhaustive and irredundant generation of candidate structures in ESESOC (Expert System for the Elucidation of the Structures of Organic Compounds), a new algorithm for computer perception of topological equivalence classes of the nodes (non-hydrog

PC/ABS BLENDS:COMPATIBILIZATION AND MECHANICAL-BEHAVIOR

PC/ABS(M) blends, encompassing the whole composition range between pure PC and ABS(M), were prepared by melt-mixing in a Brabender-like apparatus. Thermal, mechanical and impact tests were performed on compression moulded specimens. Inward Tg shifts were

BIOMIMITICS OF OXIDASE AND OXYGENASE THE ELECTRONIC SPECTRA AND THE OXYGEN UPTAKE KINTICS FOR MPc AND MTPP (M = Fe, Co, Cu, Pc AND TFP - ARE DIANIONS OF PHTHALOCYANIN AND TETRAPHENYLPORPHYRINE, RESPECTIVELY)

The reaction rates of MTPP with oxygen in air are Inas than that with pure oxygen, the ratio is roughly the same as to the partial presence of imygen in air, The influences of S-ligand etbanethiol and O- litand Vc on the above Systems have also been investigated, the former makes the MP hands having more changes and the reaction rate constants becoming greater, the latter has less influence.

氧化和加氧酶的化学模拟 Ⅰ.MPc、MTPP/DMF(M=Fe、Co、Cu、Pc和TPP分别为酞菁和四苯基卟啉环;DMF为N-N′二甲基甲酰胺)体系的电子光谱和吸氧动力学

通过电子光谱法测定MPc的Q_(0-0)带和MTPP的Soret带吸光度随时间的变化,研究了MP在DMF介质中的吸氧动力学,按竞争串行反应机理的处理,表明MP的催化活性有如下关系: MPc>MTPP;Fe>Co>Cu MTPP在空气中的吸氧速率小于在纯氧中的,其比值约相当于空气中的氧分压;研究了含硫配体巯基乙醇和含氧配体抗坏血酸对上述体系的影响,前者使MP谱带发生较大的变化,吸氧速率常数普遍增大,后者的影响较小。

Palaeoenvironmental changes from pollen record in deep sea core PC-1 from northern Okinawa Trough, East China Sea during the past 24 ka

A pollen record of core PC-1 from the northern Okinawa Trough, East China Sea (ECS), provides information on vegetation and climate changes since 24 cal. kaBP. A total of 103 samples were palynologically analyzed at 8 cm intervals with a time resolution of 230 a. Four pollen zones are recognized: zone I (812-715 cm, 24.2-21.1 cal. kaBP), zone II (715-451 cm, 21.1-15.2 cal. kaBP), zone III (451-251 cm, 15.2-10.8 cal. kaBP), zone IV (251-0 cm, 10.8-0.3 cal. kaBP), corresponding to Late MIS 3, Last Glacial Maximum (LGM), deglaciation and Holocene, respectively. The LGM is characterized by the dominance of herbs, mainly Artemisia, and high pollen influx, implying an open vegetation on the exposed continental shelf and a cool and dry climate. The deglaciation is a climate warming stage with Pinus percentage increased and Artemisia percentage decreased and a rapid sea-level rise. The Holocene is characterized by predominance of tree pollen with rapid increase in Castanea-Castanopsis indicating the development of mixed evergreen and deciduous broad-leaved forest and a warm, humid climate. Low pollen influx during the Holocene probably implies submergence of the continental shelf and retreat of the pollen source area. The vegetation indicated by pollen assemblage found in this upper zone is consistent with the present vegetation found in Kyushu, Japan. Originating from the humid mountain area of North Luzon of the Philippines, Tasmania and New Zealand, Phyllocladus with sporadic occurrence throughout PC-1 core probably suggests the influence of Palaeo-Kuroshio Current or intense summer monsoon. The observed changes in Pinus and Herbs percentage indicate fluctuations of the sea level, and high Pinus percentage corresponds to high sea level. Spectrum analysis of the pollen percentage record reveals many millennial-scale periodicities, such as periodicities of 6.8, 3.85 2.2, 1.6 ka.

A new wind vector algorithm for C-band SAR

Ocean wind speed and wind direction are estimated simultaneously using the normalized radar cross sections or' corresponding to two neighboring (25-km) blocks, within a given synthetic aperture radar (SAR) image, having slightly different incidence angles. This method is motivated by the methodology used for scatterometer data. The wind direction ambiguity is removed by using the direction closest to that given by a buoy or some other source of information. We demonstrate this method with 11 EN-VISAT Advanced SAR sensor images of the Gulf of Mexico and coastal waters of the North Atlantic. Estimated wind vectors are compared with wind measurements from buoys and scatterometer data. We show that this method can surpass other methods in some cases, even those with insufficient visible wind-induced streaks in the SAR images, to extract wind vectors.

Algorithm Studies on How to Obtain a Conditional Nonlinear Optimal Perturbation (CNOP)

The conditional nonlinear optimal perturbation (CNOP), which is a nonlinear generalization of the linear singular vector (LSV), is applied in important problems of atmospheric and oceanic sciences, including ENSO predictability, targeted observations, and ensemble forecast. In this study, we investigate the computational cost of obtaining the CNOP by several methods. Differences and similarities, in terms of the computational error and cost in obtaining the CNOP, are compared among the sequential quadratic programming (SQP) algorithm, the limited memory Broyden-Fletcher-Goldfarb-Shanno (L-BFGS) algorithm, and the spectral projected gradients (SPG2) algorithm. A theoretical grassland ecosystem model and the classical Lorenz model are used as examples. Numerical results demonstrate that the computational error is acceptable with all three algorithms. The computational cost to obtain the CNOP is reduced by using the SQP algorithm. The experimental results also reveal that the L-BFGS algorithm is the most effective algorithm among the three optimization algorithms for obtaining the CNOP. The numerical results suggest a new approach and algorithm for obtaining the CNOP for a large-scale optimization problem.

基于PC的一种新型现场总线控制系统

PC性能的不断提高及实时操作系统内核的出现，促使了一种基于PC和现场总线的新型控制系统的诞生。由于该系统成本低，占用空间少，在联网、监控等方面有突出优点，并且PC机性能已经非常可靠，所以它可以取代传统的PLC来完成实时控制任务。为了验证系统的可行性，文章系统地介绍了这类新型控制系统的优点和整体软硬件结构，并对其中一个重要的性能指标——响应时间，进行了详细分析，然后通过一个实际系统——自动传输线系统，验证了这一控制系统的可行性。

基于PC的一种新型现场总线控制系统

PC性能的不断提高及实时操作系统内核的出现,促使了一种基于PC和现场总线的新型控制系统的诞生。由于该系统成本低,占用空间少,在联网、监控等方面有突出优点,并且PC机性能已经非常可靠,所以它可以取代传统的PLC来完成实时控制任务。为了验证系统的可行性,文章系统地介绍了这类新型控制系统的优点和整体软硬件结构,并对其中一个重要的性能指标——响应时间,进行了详细分析,然后通过一个实际系统——自动传输线系统,验证了这一控制系统的可行性。

WAGO750模块与PC机之间的通讯

介绍了一种用于WAGO750-842以太网节点及系列模块与PC机之间的一种通用而又简便的通讯方法,该方法能够使PC机与WAGO750系列模块方便地进行数据交换,从而达到计算机对控制对象进行信息采集和控制输出的目的。该方法已在载人潜水器控制系统中得到成功应用,效果良好。