Fabrication and mechanical response of commingled GF/PET composites

The mechanical properties and the response to mechanical load of continuous glass fiber reinforced polyethylene terephthalate (GF/PET) laminates have been characterized. The laminates were manufactured by compression molding stacks of novel woven and warp knitted fabrics produced from commingled yarns. The laminate quality was examined by means of optical and scanning electron microscopy. Few voids were found and the laminate quality was good. Resin pockets occurred in the woven laminates, originating from the architecture of the woven fabric. The strength of the fiber/matrix interface was poor. Some problems were encountered while manufacturing the laminates. These led to fiber misalignment and consequently resulted in tensile mechanical properties that were slightly lower than expected. Flexural failures all initiated as a result of compression, and it is possible that the compression strength of the matrix material, rather than its tensile strength, might limit the ultimate mechanical performance of the composites. Flexural failures for both materials were very gradual. The warp knitted laminates were stronger and stiffer than the woven laminates. The impact behavior was also investigated; the woven laminates exhibited superior damage tolerance compared with the warp knitted laminates.     

The Inhibitive Effect of Traces of SO2 on the Oxidation of Iron

The oxidation of Fe was investigated at 500–700°C in the presence of O₂ with 0–1000 ppm SO₂. The exposures were carried out in a thermobalance and lasted for 24 h. The oxidized samples were investigated by grazing-angle XRD, SEM/EDX, GDOES and XPS. The rate of oxidation of pure iron is slowed down by traces of O₂ in O₂ below 600°C while SO₂ has no effect on oxidation rate at higher temperatures. Exposure to SO₂<600°C resulted in the formation of small amounts of sulfate at the gas/oxide interface. In addition, sulfur, probably sulfide, accumulated at the metal/oxide interface. The influence of SO₂ on oxidation rate is attributed to surface sulfate. The sulfur distribution in the scale is rationalized in terms of the thermodynamic stability of compounds in the Fe–O–S system. Exposure to SO₂ caused the formation of hematite whiskers.     

Using distance transform based algorithms for extracting measures of the fiber network in volume images of paper

Nowadays volume images are frequently used in many applications. Volume images of paper can be analyzed to increase the understanding of the complexity of the fiber network in paper and its effect on the optical and mechanical properties of paper. We show how curve and surface representations of the fiber, the fiber wall, and the fiber lumen can be computed using distance transform based algorithms. These representations are used for easy computation of wall thickness, degree of collapse, fiber length, slenderness ratio, fiber curl, and torsional resistance for the fibers. Free-fiber segments are identified, again using a distance transform based algorithm. Finally, we show tools for qualitative visual inspection of the fibers. The methods are evaluated and illustrated using both sets of synthetic and of real data. In addition to the analysis of the fiber network in paper, they can be used in many other applications where shape analysis of elongated objects is to be performed.     

Supporting Roadmapping of Quality Requirements

Would slightly better performance be significantly more valuable from a market perspective? Would significantly better performance be just slightly more expensive to implement? When dealing with performance, usability, reliability, and so on, you often end up in difficult trade-off analysis. You must take into account aspects such as release targets, end-user experience, and business opportunities. At the same time, you must consider what is feasible with the evolving system architecture and the available development resources.Quality requirements are of major importance in the development of systems for software-intensive products. To be successful, a company must find the right balance among competing quality attributes. How should you balance, for example, investments for improved usability of a mobile phone's phone book and better mobile positioning? In the context of quality requirements, decision making typically combines market considerations and design issues in activities such as roadmapping, release planning, and platform scoping. Models that address requirements prioritization in a market-driven context often emphasize functional aspects. (For a comparison of other relevant techniques with Quper, see the sidebar.) Quper provides concepts for reasoning about quality in relation to cost and value and can be used in combination with existing prioritization approaches.     

Diagnosis and therapeutic management of 18 patients with prostatic abscess

Fifty-one thyroid tumours and tumour-like lesions were analysed for instability at ten dinucleotide microsatellite loci and at two coding mononucleotide repeats within the transforming growth factor beta (TGF-beta) type II receptor (TbetaRII) and insulin-like growth factor II (IGF-II) receptor (IGFIIR) genes respectively. Microsatellite instability (MI) was detected in 11 out of 51 cases (21.5%), including six (11.7%) with MI at one or two loci and five (9.8%) with MI at three or more loci (RER+ phenotype). No mutations in the TbetaRII and IGFIIR repeats were observed. The overall frequency of MI did not significantly vary in relation to age, gender, benign versus malignant status and tumour size. However, widespread MI was significantly more frequent in follicular adenomas and carcinomas than in papillary and Hürthle cell tumours: three out of nine tumours of follicular type (33.3%) resulted in replication error positive (RER+), versus 1 out of 29 papillary carcinomas (3.4%, P = 0.01), and zero out of eight Hürthle cell neoplasms. Regional lymph node metastases were present in five MI-negative primary cancers and resulted in MI-positive in two cases.     

The role of emergency medical services in primary injury prevention. East Carolina Injury Prevention Program

Recent studies have shown a high frequency of genetic hemochromatosis in the Caucasian population. In addition, the well known organ involvement of genetic hemochromatosis was evident; more than 50% of patients develop a typical arthropathy which may result in severe physical disability. Among approximately 5000 patients referred to the rheumatology outpatient clinics of Bad Nauheim and Frankfurt with different rheumatologic diagnoses, 11 patients with typical signs of hemochromatotic arthropathy were identified. In none of those cases had the diagnosis "genetic hemochromatosis" been previously established. These patients had been treated for rheumatoid arthritis and other rheumatologic disorders over several years. All showed severe organ dysfunction due to iron overload, resulting in a reduced life expectancy. This investigation shows that knowledge of the typical signs of hemochromatotic arthropathy could lead to an earlier diagnosis of genetic hemochromatosis which is necessary to prevent the complications of iron overload in those patients.     

The anterior and posterior selective temporal lobe amobarbital tests: angiographic, clinical, electroencephalographic, PET, SPECT findings, and memory performance

The techniques, results, and problems of three types of selective temporal lobe (TL) amobarbital procedures (balloon technique with temporary occlusion of the internal carotid artery distal to the origin of the anterior choroidal artery (acha) [n = 19]; selective anterior catheterization of the acha [n = 20]; and selective catheterization of the peduncular P2-segment of the posterior cerebral artery [n = 5]) are described in a group of 40 patients with medically refractory complex partial seizures of mesial TL origin. Selective amobarbital tests were carried out before surgery to predict the memory deficit after an intended selective amygdalohippocampectomy. The effects of selective anaesthetization of TL were correlated with clinical data, pattern and duration of amobarbital induced EEG changes, and performance on verbal and nonverbal memory tasks measured during the test. In 4 patients the effect of selective amobarbital injection on regional and global metabolism was studied with 18F-FDG-PET, with the PET tracer being injected intravenously immediately after amobarbital. More recently in 2 patients the vascular territory perfused by amobarbital in the acha test was studied with SPECT using 99m Tc ECD injected immediately prior to the amobarbital into the acha. Whereas the PET studies showed a rather widespread and bilateral amobarbital-induced decrease of metabolism, the SPECT studies confirmed the selective distribution of the tracer in the vascular territory of the acha, i.e., in amygdala and hippocampus. The comparison of selective TL amobarbital test performance with postoperative neuropsychological performance showed that the predictive value of this test is rather good for the postoperative verbal memory but underestimates postoperative nonverbal ("figural") memory performance.     

New developments at JET in diagnostics, real-time control, data acquisition and information retrieval with potential application to ITER

In magnetic confinement fusion, the operation of next generation devices will be significantly different compared to present day machines. The duration length of the discharges will require abandoning the traditional paradigm of processing and storing the data after the shot. In fact most information will have to be made available in real-time. The significant issues of machine protection will require more sophisticated and at the same time more robust feedback control schemes. Another very important issue emerged in the last years of JET operation, and which is expected to become more severe in ITER, is the large amount of data to be analysed, which cannot be handled in the most efficient way with traditional methods.In order to prepare for the operation of ITER, some tests are being performed at JET. The capacity of the real-time network has increased in the last years, and many more systems, mainly diagnostics have been connected to it in order to test their reliability and to assess the quality of the information they can provide for feedback control. To reduce the amount of data, a prototype of real-time adaptive data acquisition techniques is being implemented, to adjust the acquisition frequency to the time resolution of the phenomena to be analysed in the plasma. Lossless data compression techniques have been refined and various intelligent signal processing methods have already been implemented to allow an easier and more objective first screening of the data. To allow scientists from wide and diffuse communities to participate in the scientific and technical programme, various innovative tools for remote participation and experimentation are also being actively investigated.     

TEM Investigation of the Microstructure of the Scale Formed on a FeCrAlRE Alloy at 900 °C: The Effect of Y-rich RE Particles

Three oxide features: the thin and smooth protective oxide, reactive element (Ti-, Zr- or Y-rich) particles, and patches of thick oxide surrounding the Y-rich reactive element particles, were observed on a commercial FeCrAlRE alloy, Kanthal AF, exposed at 900 °C. The microstructural development of the patches of thick oxide was investigated on samples exposed for 24 or 168 h in either dry O₂ or O₂ + 40% H₂O. Analytical transmission electron microscopy in combination with site-precision TEM sample preparation by FIB/SEM was used. In all patches a thin but continuous inward growing α-Al₂O₃ layer was formed under a thick outward growing alumina layer, which initially consisted only of γ-Al₂O₃. In dry O₂, transformation of γ-Al₂O₃ (in the outer layer) to α-Al₂O₃ had started during 24 h and a considerable amount of γ-Al₂O₃ had transformed after 168 h. The transformation originated immediately above the inward growing α-Al₂O₃. No such transformation occurred in O₂ + H₂O. The possible effects of the Y-rich RE particles, as well as the effects of water vapour, on the oxidation were discussed.     

Oxidation behavior at 300–1000 °C of a (Mo,W)Si2-based composite containing boride

The oxidation behavior of a (Mo,W)Si₂ composite with boride addition was examined at 300–1000 °C for 24 h in dry O₂. The oxidation kinetics was studied using a thermobalance, and the oxide scales were analyzed using a combination of electron microscopy (SEM/EDX, FIB, BIB) and XRD. Accelerated oxidation was found to occur between 500 °C and 675 °C, with a peak mass gain at 625 °C. The rapid oxidation is attributed to the vaporization of molybdenum oxide that leaves a porous and poorly protective silica layer behind. At higher temperature (700–1000 °C) a protective scale forms, consisting of a dense SiO₂/B₂O₃ glass.