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In order to increase the wettability between carbon fiber and aluminum matrix, pure nickel was applied as coating on carbon fiber. And scanning electron microscopy was used to characterize the microstructure of the coating, fiber and matrix. The tensile tests of carbon fiber and aluminum matrix were done to examine how the behavior of nickel layers with variation of applied pressure make an effect on the mechanical properties of composites. As the applied pressure increases, nickel layers were resolved into the aluminum matrix and ultimate tensile strength of the composite decreased. This was due to premature fracture of the reaction layer acting as a surface notch.

The existing accelerator facility at the Max-Planck-Institute in Heidelberg consists of a 12 MV tandem Van de Graaff accelerator, a post-accelerator and a heavy ion cooler storage ring TSR. Many experiments at the TSR, especially laser cooling, are limited by the low current delivered by the MP tandem. A new injector consisting of a high current source, two RFQs and eight seven-gap resonators will increase the currents for singly charged ions by up to three orders of magnitude. In a second phase, an ECR source for highly charged ions will be added and the high current injector will be used in combination with the Heidelberg heavy ion post-accelerator. This new system will deliver beams up to uranium with energies above the Coulomb barrier of the heaviest elements. In this paper the design and the status of the project are presented.

Mushrooms are popular both as food and as a source of natural compounds of biopharmaceutical interest. Some mushroom-derived compounds such as beta-glucan have been shown to be immunostimulatory; this study explores the anti-inflammatory properties of hispidin analogues derived from the mushroom, Inonotus xeranticus. We sought to identify the molecular mechanism of action of these hispidin analogues by determining their effects on lipopolysaccharide (LPS)-mediated inflammatory responses in a macrophage cell line.The production of inflammatory mediators was determined by Griess assay, reverse transcription-PCR and ELISA. The inhibitory effect of davalliactone on LPS-induced activation of signalling cascades was assessed by western blotting, immunoprecipitation and direct kinase assay.In activated RAW264.7 cells, davallialactone strongly downregulated LPS-mediated inflammatory responses, including NO production, prostaglandin E2 release, expression of proinflammatory cytokine genes and cell surface expression of co-stimulatory molecules. Davallialactone treatment did not alter cell viability or morphology. Davallialactone was found to exert its anti-inflammatory effects by inhibiting a signalling cascade that activates nuclear factor kappa B via PI3K, Akt and IKK, but not mitogen-activated protein kinases. Treatment with davallialactone affected the phosphorylation of these signalling proteins, but not their level of expression. These inhibitory effects were not due to the interruption of toll-like receptor 4 binding to CD14. In particular, davallialactone strongly inhibited the LPS-induced phosphorylation and kinase activity of Src, implying that Src may be a potential pharmacological target of davallialactone.Our data suggest that davallialactone, a small molecule found in edible mushrooms, has anti-inflammatory activity. Davallialactone can be developed as a pharmaceutically valuable anti-Src kinase agent.

Ginsenosides, or ginseng saponins, are biologically active ingredients of Panax ginseng. Accumulating evidence suggests that ginsenosides can alleviate pain from injections of noxious chemicals, such as capsaicin [Nah et al. (2000)]. In this study we examined the effects of ginsenoside Rc on the capsaicin-induced inward current in Xenopus oocytes that expresses the vanilloid receptor 1 (VR1). Ginsenoside Rc enhanced the capsaicin-induced inward current in a concentration-dependent and reversible manner, but ginsenoside Rc itself elicited no membrane currents. The VR1 antagonist capsazepine almost completely blocked the inward current that was elicited by capsaicin plus ginsenoside Rc. We also tested the effect of seven other fractionated ginsenosides (i.e., Rb1, Rb2, Rd, Re, Rf, Rg1, and Rg2) in addition to ginsenoside Rc. We found that six of them significantly enhanced the inward current that is induced by capsaicin with the following order of potency: RcRfRg1 approximately RdRb2Rb1. These results show the possibility that the in vivo effect of ginsenosides against capsaicin-induced pain is derived from their modulation of the VR1 channel function.

According to an irradiation damage model, the profile of an implanted ion at temperatures great enough for diffusion to occur will depend on the defect sink density in the material. To test this model, pure silicon wafers were prepared with high and low defect densities. These wafers were implanted with about 5 × 1019 As +2 m 2 at − 196, 300, and 600°C. After implanting the profiles were measured using Rutherford backscattering spectroscopy and secondary ion mass spectroscopy. The observed spreading of the As-profile contradicts initial theoretical predictions.

High temperature chlorine contaminated environments may be encountered in a number of modern industrial and energy conversion systems. Such environments have been shown to be extremely severe from a corrosion control standpoint. Rather little information is available on the corrosion properties of alloys in these environments, and the bulk of this information has been obtained in shortterm tests (24 hours or less). This paper will report the results of a series of high temperature corrosion tests performed on superalloys for periods up to 400 hours in an oxidizing environment consisting of argon containing 20 pet oxygen and 0.25 pct chlorine at 900 ° C.

Silicon is believed to be an almost perfectly brittle material with cleavage occurring on {111} planes. In such a material at room temperature cleavage is expected to occur prior to any dislocation nucleation. This behavior suggests that cleavage fracture may be used to produce usable flat surfaces. Attempts to show this have failed. Such fractures produced in semiconductor silicon tend to occur on planes of variable orientation resulting in surfaces with a poor surface finish. In order to learn more about the mechanisms involved in fracture of silicon we began a HREM study of hardness indent induced fractures in thin samples of oxidized silicon.Samples of single crystal silicon were oxidized in air for 100 hours at 1000°C. Two pieces of this material were glued together and 500 μm thick cross-section samples were cut from the combined piece. The cross-section samples were indented using a Vicker's microhardness tester to produce cracks. The cracks in the samples were preserved by thinning from the back side using a combination of mechanical grinding and ion milling.