连续式PTT工艺

简要介绍了聚对苯二甲酸丙二酯(PTT)的应用、市场和工艺发展。重点分析了间歇式和连续式聚合物工艺的不同及对产品质量的影响。详细介绍了吉玛公司PTT民用长丝的纺丝工艺——冷态工艺加上改性剂。     

Properties of tin/plasma polymer nanocomposites

Thin composite layers (tin in plasma polymer matrix) were prepared in a stainless steel vacuum chamber. An RF powered magnetron with tin target was used to excite the discharge and to activate the monomer species (n-hexane). The gas mixture introduced comprised Ar and n-hexane vapours. The properties of the films and chemical composition were characterized by AFM (surface morphology), TEM and Electron tomography (bulk structure characterization), XPS and FTIR spectroscopy (chemical composition analyses). Current-voltage characteristics were measured to examine the electrical properties of the layers and their dependence on the deposition parameters.     

Trübungsmessung von Lipoproteinen nach Polyanionen-Präzipitation auf dem Autoanalyzer

Turbidity Measurement of Lipoproteins after Polyanion Precipitation in the Autoanalyzer A new method for the diagnosis of fat metabolism disorders is given. Using this method, hyperlipemia are detected by turbidity measurement after selective precipitation of lipoproteins in serum with the aid of polyanions. A comparison of the turbidity measurement with the determination of triglycerides and cholesterol gave a good agreement with a correlation of 95%. Furthermore, it was found that different types of hyperlipemia with increased levels of VLDL and LDL or HDL can be distinguished by selective precipitation of VLDL and LDL with heparine and MgCl₂, and of all the lipoproteins with dextrane sulfate and CaCl₂, respectively.     

Reconstruction of volume data with quadratic super splines

We propose a new approach to reconstruct nondiscrete models from gridded volume samples. As a model, we use quadratic trivariate super splines on a uniform tetrahedral partition. We discuss the smoothness and approximation properties of our model and compare to alternative piecewise polynomial constructions. We observe, as a nonstandard phenomenon, that the derivatives of our splines yield optimal approximation order for smooth data, while the theoretical error of the values is nearly optimal due to the averaging rules. Our approach enables efficient reconstruction and visualization of the data. As the piecewise polynomials are of the lowest possible total degree two, we can efficiently determine exact ray intersections with an isosurface for ray-casting. Moreover, the optimal approximation properties of the derivatives allow us to simply sample the necessary gradients directly from the polynomial pieces of the splines. Our results confirm the efficiency of the quasi-interpolating method and demonstrate high visual quality for rendered isosurfaces.