TMS320VC54x处理器McBSP接口的设计和实现

以低速语音编解码系统为例．介绍了TMS320VC54x数字信号处理器的多通道缓冲串口的软硬件设计，给出了具体的设计思想和实现方法。     

Fluorination of CN x Nanotubes

Abstract

Multiwall CN _x nanotubes have been prepared by thermal decomposition of acetonitrile over Co/Ni catalytic particles. The fluorination of nanotubes was performed at room temperature by using a gaseous mixture of BrF₃ and Br₂. Transmission electron microscopy (TEM) and x‐ray diffraction (XRD) indicated that only the outer shells of CN _x nanotubes were fluorinated, whereas the inner shells remained intact. X‐ray photoelectron spectroscopy (XPS) showed an oxidation of pyridinic‐type nitrogen with tube fluorination.     

Nano-to-macroporous TiO2 (anatase) by cold sintering process

Cold Sintering Process (CSP) was applied on commercial nanopowders to produce nanostructured TiO₂ anatase with nano-to-macro porosity. Nanoporous TiO₂ based materials were obtained by applying CSP at 150 °C and pressures up to 500 MPa on three TiO₂ nanopowders with different specific surface area (s.s.a. = 50, 90 and 370 m²/g), using water as transient aqueous environment. Although TiO₂ is insoluble in water, a density of 68% and s.s.a. = 117 m²/g were achieved from the powder with the highest specific surface area. A post annealing process at 500 °C increased the density up to 73% with a s.s.a. = 59 m²/g, and the crystallites dimensions passed from 110 Å in the powder to 130 Å in CSP material and 172 Å after post annealing. Finally, macroporosity was produced by using thermoplastic polymer beads as sacrificial templates within TiO₂ nanopowder during CSP, followed by a debonding at 500 °C.     

Comparative polyphenolic antioxidant profile and quality of traditional apple cultivars as affected by cold storage

‘Kathista’ and ‘Lortiko’ are regarded as traditional and highly appreciated apple cultivars in Cyprus, yet their postharvest behaviour and phytochemical content are largely unknown. Such fruits were examined for their qualitative traits, phenolic composition and antioxidant capacity after harvest or short, intermediate or extended cold storage and additional ripening at room temperature (RT), using ‘Gala’ as reference cultivar. Total phenolic content was dependent on cultivar and length of cold storage, while hydroxycinnamic acids were always at higher levels compared to total flavonols for all the examined cultivars. No clear trends regarding the influence of cold storage or RT maintenance on fruit antioxidant properties were evident. Overall, quality attributes and polyphenolic content of the traditional apple cultivars were comparable with ‘Gala’ at harvest; thus, they can be considered a good source of nutraceuticals as summer apple cultivars. However, extended cold storage deteriorates fruit behaviour and antioxidant capacity, particularly in ‘Lortiko’ fruit.     

Polynomial filtering for nonlinear stochastic systems with state‐ and disturbance‐dependent noises

This article is concerned with the polynomial filtering problem for a class of nonlinear stochastic systems governed by the Itô differential equation. The system under investigation involves polynomial nonlinearities, unknown‐but‐bounded disturbances, and state‐ and disturbance‐dependent noises ((x,d)‐dependent noises for short). By expanding the polynomial nonlinear functions in Taylor series around the state estimate, a new polynomial filter design method is developed with hope to reduce the conservatism of the existing results. In virtue of stochastic analysis and inequality technique, sufficient conditions in terms of parameter‐dependent linear matrix inequalities (PDLMIs) are derived to guarantee that the estimation error system is input‐to‐state stable in probability. Moreover, the desired polynomial matrix can be obtained by solving the PDLMIs via the sum‐of‐squares approach. The effectiveness and applicability of the proposed method are illustrated by two numerical examples with one concerning the permanent magnet synchronous motor.     

Theoretical prediction of Grüneisen parameter for bulk metallic glasses

The Grüneisen parameter (γ) is of considerable importance to Earth scientists because it sets limitations on the thermo elastic properties of the lower mantle and core. However, there are several formulations of the Grüneisen parameter in frequent use which not only give different values for Grüneisen parameter at ambient pressure but also predict a varying dependence of Grüneisen parameter as a function of compression. The Grüneisen parameter is directly related to the equation of state (EOS), yet it is often the case that both the form of and the EOS are chosen independently of each other and somewhat arbitrarily. In this paper we have assessed some of the more common definitions of the Grüneisen parameter and the EOS's, and have applied them to test the validity of EOS for six different bulk metallic glasses.     

Properties of Auger electrons following excitation of polarized atoms by polarized electrons

In non-relativistic approximation, the most general expression for differential cross sections describing the properties of Auger-electron emission induced in the excitation of polarized atoms by polarized electrons is obtained for the first time. The ways of the application of the general expressions suitable for the specific experimental conditions are outlined by deriving the expressions for the asymmetry parameters and the magnetic dichroism of the angular distribution of the Auger electrons as well as of the angular correlations between the scattered and Auger electrons.     

低温脱硝催化剂研究进展

在传统选择性催化还原技术（SCR）催化剂的基础上,分别以钒-钛系催化剂、固溶体催化剂和新型MnO _x 催化剂为重点介绍了近些年低温SCR催化剂的研究进展,综述了不同活性组分的复合型催化剂的制备方法、元素掺杂、反应机理和抗性等,并通过分析不同复合型催化剂的表征总结了催化剂的性能状况以及低温脱硝效率,着重阐述了新型MnO _x 催化剂所具有的优异脱硝特性,认为通过改性提高新型MnO _x 的抗水抗硫性将会成为该领域未来的发展方向和研究热点,最后介绍了不同负载体对新型MnO _x 催化剂的催化效率的影响规律,发现二氧化钛负载体具有良好的抗水性,三氧化二铝负载体能显著增强催化活性,二氧化铈负载体的热稳定性较好。     

Static and dynamic corrosion behavior of SnO2-doped AZS slip cast refractory in SLS glass

The corrosion behavior of a tin IV oxide-doped AZS-refractory, subject to static and dynamic corrosion testing at 1370˚C in soda-lime-silica glass, was studied considering the effect of the microstructural features on corrosion. The refractory was synthesized by slip cast methods through reaction sintering of alumina and zircon raw materials using SnO₂ as a sintering agent. SnO₂ had a considerable influence in the enhanced alumina/zircon reaction sintering and the subsequently evolved microstructures of an interlocked Zr_(1-x)Sn_(x)O₂ solid solution reinforced alumina-mullite composite. The process kinetics of the refractory corrosion followed reasonably well the predicted dependence on the square root of angular velocity under forced convection corrosion. Glass chemical corrosion and erosion of the refractory, under static and dynamic glass conditions, respectively, revealed the Zr_(1-x)Sn_(x)O₂ solid solution-rich mullite matrix as providing the most corrosion resistance and glass compatibility.