bluuebunny/crossref_metadata_2025_split huggingface dataset:
Design of wear and corrosion resistant PVD‐coatings for magnesium alloys
Authors: Hoche H. , Allebrandt D. , Scheerer H. , Broszeit E. , Berger C. 
Published: April 2007

AbstractAlthough magnesium alloys became popular in the first half of the 20th century, the bad corrosion properties prevented their breakthrough in industrial mass production. Since the technology for the production of high purity alloys was introduced in the 1970s, magnesium alloys became more and more in the focus of industrial attention. Today magnesium alloys are state of the art in structural parts in automotive industry. Despite its outstanding properties like good castability, low density and nearly unlimited availability the negative aspects like weak corrosion and wear behaviour still limit the application of magnesium in industry [1]. So, the only economic solution is the deposition of a coating or a suitable surface treatment which provides both, wear and corrosion resistance. Today, plasma electrolytic anodisations are state of the art [2–5]. They provide acceptable corrosion resistance and protect the magnesium from mechanical damage due to their high hardness. On the other hand, their high porosity limits their use in combination with electrochemically noble materials, leading to galvanic corrosion [6]. In addition, the high surface roughness of the plasma electrolytic anodisations restricts their use in tribological applications, particularly under dry sliding conditions [7].On the other hand, due to the high life time recommendations the application of magnesium in the automotive industries motion component field is a long term process. Nevertheless, there is a quite high industrial interest to apply magnesium in the motion component field in consumer applications like do‐it‐yourself or gardenig. Some examples are motor components of lawnmovers, motor saws or drills. Especially for these fields of application there are quite high demands on the corrosion properties due to undefined storage and the conditions during usage.In order to achieve smooth surfaces with high quality, the PVD technology moves into the centre of interest. Since the 1980s PVD coatings are well established and widely used for different industrial applications, mainly for steel and tool coatings. The authors were the first who carried out serious studies on the development of PVD coatings for magnesium alloys since 1999 [6, 7].The extensive research activities lead to the recent development of a coating system, which provides both, good wear properties as well as good corrosion behaviour.
Bruchanalyse an Hohlgläsern
Authors: Hosemann H.‐J. , Hof P. 
Published: April 2007

AbstractDie Bruchanalyse ist ein wichtiger Bestandteil der Klärung von Schadensfällen von Hohl‐ oder Verpackungsgläsern. Da es sich bei Schadensfällen mit zum Beispiel unter Innen‐Überdruck stehenden Flaschen häufig auch um gesundheitliche Schäden handelt, kommt der Bruchanalyse und der damit verbundenen Ursachenforschung eine große Bedeutung zu. Verschiedene Merkmale auf den Oberflächen von Glasbruchstücken und das gesamte Bruchbild selbst geben Hinweise auf die Rissausbreitungsrichtung, die im Bruchfalle anliegenden Spannungen und auf die Ursache der Spannung. Eine Rekonstruktion der Flasche selbst ist ein weiteres hilfreiches Mittel zur Ursachenforschung. Die Unterschiede der verschiedenen Oberflächenmerkmale werden im Folgenden erläutert. Außerdem werden an hand zum Beispiel von Bruchbildern verschiedener Bruchursachen und ‐mechanismen vorgestellt und diskutiert
Verhalten geschweißter Magnesiumlegierungen unter mechanisch‐korrosiver Komplexbeanspruchung
Authors: Eppel K. , Ellermeier J. , Troßmann T. , Berger C. 
Published: April 2007

AbstractNeben dem weit verbreiteten Einsatz von Magnesium‐Gusslegierungen bieten Magnesium‐Knetlegierungen ein hohes Leichtbaupotenzial insbesondere in der Automobilindustrie. Die Verarbeitung von Walz‐ bzw. Strangpressprodukten aus Magnesiumlegierungen (Profile und Bleche) erfordert geeignete Fügeverfahren zur Verbindung dieser Halbzeuge. Im Rahmen der Realisierung von Leichtbaukonzepten werden hohe Anforderungen an die Werkstoffe und Fügeverfahren gestellt, sodass die Eigenschaften der Verbindungen, sowohl im Hinblick auf Wirtschaftlichkeit und mechanische Festigkeitskennwerte, als auch bezüglich ihres Korrosionsverhaltens, von großem Interesse sind. Beim Schweißen von Magnesiumlegierungen kommt es zu Beeinflussungen der Oberfläche, des Eigenspannungszustandes und des Gefüges. Diese hängen insbesondere von der eingebrachten Wärme ab und sind somit abhängig vom Schweißverfahren und den Verfahrensparametern und beeinflussen das Korrosionsverhalten in der Schweißzone. Es werden Untersuchungen zum Korrosionsverhalten (mit und ohne überlagerte zyklische Belastung) verschiedener Schweißverbindungen von Blechen aus Magnesiumlegierungen (AZ31, AZ61, AZ91) dargestellt, die mittels Plasma‐, Laserstrahl‐, Elektronenstrahlschweißen im Vakuum und an Atmosphäre geschweißt wurden. Dabei werden wesentliche Einflussgrößen auf das Korrosionsverhalten von Magnesium‐Schweißverbindungen dargestellt und Maßnahmen, die zur Verbesserung des Korrosionsverhaltens beitragen können, aufgezeigt.
Intraneural perineurioma of the radial nerve visualized by 3.0 Tesla MRI
Authors: Nguyen Doris , Dyck P. James , Daube Jasper R. 
Published: April 2007

AbstractA progressive radial neuropathy of unknown etiology despite 1.5T magnetic resonance imaging (MRI) and surgical exploration was identified as an intraneural perineurioma by a localized Tinel's sign, an enlarged radial nerve at the spiral groove by 3.0T MRI, and a fascicular biopsy. The distinction between the initial diagnoses of inflammatory, demyelinating polyneuropathy and perineurioma was made by immunohistochemistry and electron microscopy. A slowly progressing, localized mononeuropathy should include perineurioma in the differential diagnosis. Muscle Nerve, 2007
Lower and upper bounds for the degree‐constrained minimum spanning tree problem
Authors: da Cunha Alexandre Salles , Lucena Abilio 
Published: April 2007

AbstractIn this paper, we propose a Lagrangian Non‐Delayed Relax‐and‐Cut algorithm for the Degree‐Constrained Minimum Spanning Tree Problem (DCMSTP). Since degree‐constrained trees are the common vertices of the Spanning Tree and the b‐Matching polytopes, strengthened DCMSTP lower bounds are generated through the use of Blossom Inequalities (BIs). BIs are facet defining for the b‐Matching Polytope and, to the best of our knowledge, have never been used before for DCMSTP. Lagrangian information is also used here, in a Kruskal style algorithm (followed by local search) to obtain valid DCMSTP upper bounds. Whenever optimality could not be proven by Relax‐and‐Cut alone, Lagrangian lower bounds are carried over to a cutting plane algorithm, without the need for solving any separation problem. This is accomplished after identifying, at Relax‐and‐Cut, a small set of attractive Subtour Elimination Constraints and BIs. Computational results, on Euclidean and on random cost DCMSTP instances, indicate that our Relax‐and‐Cut lower bounds either dominate or else are competitive with linear programming and Lagrangian relaxation lower bounds found in the literature. Furthermore, our upper bounds appear competitive with the best in the literature. © 2007 Wiley Periodicals, Inc. NETWORKS, Vol. 50(1), 55–66 2007
Grading gastrointestinal dysplasia and what to call it when you don't know what it is
Authors: Offerhaus GJ 
Published: April 2007

AbstractDysplasia in the gastrointestinal tract is defined as intraepithelial neoplasia (IEN) according to the WHO nomenclature. Neoplastic growth in the gastrointestinal tract evolves through stepwise tumour progression in which consecutive morphological stages are characterized by increasing genetic instability accompanied by specific genetic alterations. Invasive cancer is preceded by non‐invasive precursor stages and the clonal epithelial cell proliferation in these pre‐invasive stages is diagnosed as dysplasia or IEN. Dysplasia is therefore a marker for cancer risk and guides surveillance. Dysplasia is conventionally graded using a two‐tier system and low‐ and high‐grade dysplasia convey different connotations regarding cancer risk. This perspective argues that the critical differential diagnosis is the one between neoplastic and non‐neoplastic epithelial cell proliferations and the relevance of grading dysplasia is questionable. It is furthermore expected that a molecular signature will predict the propensity to invasive carcinoma more accurately than routine histopathology in the near future. Research in this field needs to focus on a combination of biomarkers representing genetic instability, clonal mutations, and genetic clonal divergence. Copyright © 2007 Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd.
The α1 subunit of the sodium pump could represent a novel target to combat non‐small cell lung cancers
Authors: Mijatovic T , Roland I , Van Quaquebeke E , Nilsson B , Mathieu A , Van Vynckt F , Darro F , Blanco G , Facchini V , Kiss R 
Published: April 2007

AbstractWith an overall 5 year survival rate as low as 15% for non‐small cell lung cancer (NSCLC), even with surgical intervention and the use of newer molecules in adjuvant chemotherapy, there is an urgent need for new biological targets and associated novel anti‐cancer agents. The present study was undertaken to evaluate the potential of the Na+/K+‐ATPase α1 subunit as a novel target in NSCLC and revealed that α1 expression is markedly higher in a significant proportion of NSCLC clinical samples compared to normal lung tissue. Furthermore, reduction in α1 expression in A549 NSCLC cells by anti‐α1 siRNA resulted in markedly impaired proliferation and migration of these cancer cells. Finally, of three cardenolides investigated, UNBS1450, which is known to bind to Na+/K+‐ATPase and displays potent anti‐tumour activity in vivo in experimental models of human NSCLCs, is the most potent inhibitor of Na+/K+‐ATPase isozymes (α1β1, α2β1 and α3β1), most strikingly of α1β1. This was reflected in the compound's more potent anti‐proliferative activity in all NSCLC cell lines evaluated (A549, Cal‐12T, NCI‐H727 and A427); the first three of which over‐express α1. The marked impairment in A549 NSCLC cell proliferation and migration, and resulting similar morphology following anti‐α1 siRNA or UNBS1450 treatment, was associated with features of abnormal cytokinesis, mediated in the case of UNBS1450 by disorganization of the actin cytoskeleton. Collectively these data strongly suggest that targeting the Na+/K+‐ATPase α1 using specific cardenolides could represent a novel means to combat certain NSCLCs. Copyright © 2007 Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd.
Transcriptional silencing of the TMS1/ASC tumour suppressor gene by an epigenetic mechanism in hepatocellular carcinoma cells
Authors: Zhang C , Li H , Zhou G , Zhang Q , Zhang T , Li J , Zhang J , Hou J , Liew CT , Yin D 
Published: April 2007

AbstractDNA methylation and histone modifications have emerged as key mechanisms in transcriptional regulation. The target of methylation‐induced silencing 1 (TMS1) is a bipartite protein. Recent studies have indicated that methylation‐associated silencing of TMS1 occurs in many cancers. However, whether and how TMS1 is regulated by epigenetic mechanisms in cancers remains unknown. In this study we showed that methylation of the TMS1 promoter occurred in five of six hepatocellular carcinoma (HCC) cell lines. TMS1 expression was reduced in four HCC cell lines and correlated with methylation status. Furthermore, the TMS1 promoter was completely methylated and mRNA expression was undetectable. TMS1 expression could be restored by 5‐aza‐2′‐deoxycitidine (5‐Aza‐dC) (a DNA methyltransferase inhibitor) or trichostatin A (TSA) (a histone deacetylase inhibitor) alone and the promoter methylation was partially reversible. TSA was more efficient than 5‐Aza‐dC in inducing TMS1 expression, and the combination of 5‐Aza‐dC and TSA resulted in markedly synergistic reactivation of the gene and completely reversed promoter methylation. Interestingly, TMS1 promoter methylation‐associated gene silencing was accompanied by histone H3 Lysine 9 (H3K9) hypoacetylation and trimethylation. 5‐Aza‐dC and/or TSA also had some effect on conversion of methylated to acetylated H3K9 in restoring TMS1. This conversion was dynamic at the TMS1 promoter and a decrease in H3K9 trimethylation preceded an increase in H3K9 acetylation after 5‐Aza‐dC and/or TSA treatment. Our results thus suggest that epigenetic inactivation of TMS1 expression is regulated by promoter hypermethylation and H3K9 modifications in a coordinated way. Copyright © 2007 Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd.
Enhancement of wood/polyethylene composites via compatibilization and incorporation of organoclay particles
Authors: Zhong Yang , Poloso Tony , Hetzer Max , De Kee Daniel 
Published: April 2007

AbstractDespite many advantages of wood–polyethylene composites, the shortcomings of this kind of composite include relatively low modulus, low notched impact resistance, relatively large thermal expansion, as well as substantial creep. In this article, in addition to using maleic anhydride grafted polyethylene as compatibilizer, organoclay was introduced into the polyethylene matrix so as to further enhance the thermal and mechanical performance. First, the influence of maleic anhydride grafted polyethylene type and loading on the morphology and properties of wood/HDPE composites was studied. Then, the effects of organoclay loading and of the compounding procedure on the wood/HDPE composites were investigated. The compatibilization was found to result in better polymer impregnation on the wood, reduced linear thermal expansion coefficients, and significantly improved mechanical properties. Incorporation of organoclay further reduced the thermal expansion and elevated the heat deflection temperature. More compatibilizer is needed to maintain the mechanical properties with the presence of clay. POLYM. ENG. SCI., 47:797–803, 2007. © 2007 Society of Plastics Engineers
The role of plug design in determining wall thickness distribution in thermoforming
Authors: Martin P.J. , Duncan P. 
Published: April 2007

AbstractAn experimental investigation has been carried out into the effects of changes in plug design on the wall thickness distribution of thermoformed products. Plugs were machined with a series of geometrical variations and their effects on the process were measured. The overall results show that the plug has a crucial role in controlling the wall thickness distribution in thermoforming. Larger plugs tend to distribute more material to the base of the product, but the introduction of a small sidewall taper, base radius, or a reduction in plug diameter tend to lead to more balanced distributions. However, larger changes in any of the variables tend to destroy these benefits. It has also been demonstrated that the frictional and thermal properties of the plug are important in determining the deformation response of the sheet material. There is a clear evidence of slip in the sheet during plug contact and, although the cooling effect of the plug appears to be minimal, cooling in the highly deformed regions away from the plug appears to be a significant factor. POLYM. ENG. SCI., 47:804–813, 2007. © 2007 Society of Plastics Engineers
Quantitative description of polychloroprene and piperylene–styrene blend films surface morphology
Authors: Jankauskaitė Virginija , Žukienė Kristina , Petraitienė Stasė 
Published: April 2007

AbstractSurface morphology of polychloroprene (CR) and piperylene–styrene copolymer (PSC) blend films was investigated by atomic force microscopy. The dependence of the blend films surface roughness on PSC content was studied with both fractal and correlation analyses. Gaussian profiles for the height distribution upon blend composition were observed. The topographical images of CR/PSC blends have been characterized by root‐mean‐square roughness, lateral parameter, and fractal dimension values. The analysis showed that quantitative description of surface roughness leads to the differentiation components of polymers blends. Lateral parameter and fractal dimension values of CR films were similar to those of CR/PSC 60/40 wt% blend films. This effect is associated with CR enrichment at the blend film surface. POLYM. ENG. SCI., 47:824–829, 2007. © 2007 Society of Plastics Engineers
Preparation and characterization of rubber‐toughened poly(trimethylene terephthalate)/organoclay nanocomposite
Authors: Mishra Joy K. , Chang Young‐Wook , Choi Nak Sam 
Published: April 2007

AbstractRubber‐toughened poly(trimethylene terephthalate) (PTT)–organoclay nanocomposite (RTPTTCN) was prepared by a melt mixing technique. The rubber‐toughened PTT (RTPTT) was made by blending it with ethylene propylene diene terpolymer (EPDM) and with a small amount of maleated EPDM as a compatibilizer. XRD and TEM analysis indicated that the RTPTTCN forms a partially exfoliated nanocomposite. It was observed from SEM analysis that the clay nanoparticles induced a reduction of rubber particle size in the PTT matrix. Tensile and dynamic mechanical analysis indicated that the clay nanoparticles enhance the stiffness of the RTPTT without adversely affecting its toughness. Melt rheological studies revealed that the nanocomposites exhibited strong shear thinning behavior, and a percolated network of the clay particles was formed. It was also observed from DSC that the clay nanoparticles caused an increase in the nonisothermal crystallization temperature of the PTT. POLYM. ENG. SCI., 47:863–870, 2007. © 2007 Society of Plastics Engineers
Finite element analysis for wavelike flow marks in injection molding
Authors: Kang Sung Yong , Kim Seung Mo , Lee Woo Il 
Published: April 2007

AbstractWavelike flow marks are a kind of surface defect that can arise during the filling stage of the injection molding process. In this study, we performed a numerical analysis using a finite element method to predict the conditions under which flow marks are generated. To simplify the analysis, a two dimensional flow through a channel between two parallel plates was considered. The viscosity of the polymer melt was modeled by the Cross‐WLF equation. For the finite element analysis, a velocity–pressure formulation was used to simultaneously solve the continuity and momentum equations. The calculation domain for the numerical analysis keeps changing with time due to the advancing melt front. To handle the free surface more accurately, a moving grid method was employed. A numerical mesh was generated at each time step using an automatic mesh generation scheme. An analytical model was developed to correlate the effects of process variables to the flow mark geometry. Results of the numerical analysis were compared with the available experimental data. The estimated geometry of the flow marks were in good qualitative agreement with experimental observations. Parametric studies have been performed to examine the effects of various processing conditions and the material properties on flow mark size. POLYM. ENG. SCI., 47:922–933, 2007. © 2007 Society of Plastics Engineers
High strength polyethylene fibers from high density polyethylene/organoclay composites
Authors: Chantrasakul Siripan , Amornsakchai Taweechai 
Published: April 2007

AbstractHigh strength fibers were prepared from high density polyethylene (HDPE)/organically modified montmorillonite (OMMT) composites. X‐ray diffraction study revealed that the composites were of conventional or phase‐separated type. As‐spun composite fibers were found to have higher drawability than as‐spun HDPE fiber. As a result of an increased drawability, fibers with much higher mechanical properties were obtained. The highest modulus and tensile strength obtained in the present study were 38 GPa and 1.7 GPa, respectively. Study of internal morphology suggests that the role of OMMT is to suppress a defect formation and allows the fiber to be drawn to higher draw ratio. Analysis of the mechanical properties of the fibers using a Griffith type relationship suggested that the fibers have much smaller defects and the predicted attainable strength for the fiber is much higher than that previously predicted for melt‐spun and hot drawn fiber. POLYM. ENG. SCI., 47:943–950, 2007. © 2007 Society of Plastics Engineers
Morphology effect on the hydrothermal ageing of a thermoplastic modified epoxy thermoset
Authors: Arribas C. , Sepúlveda L. , Salom C. , Masegosa R.M. , Prolongo M.G. 
Published: April 2007

AbstractThe hydrothermal ageing of an epoxy thermoset modified with different amounts of poly(vinyl acetate), PVAc, was studied by gravimetric analysis, dynamic mechanical thermal analysis, and scanning electron microscopy. Differences in the water uptake process were observed as a function of the PVAc content, these differences were related to the morphology. Samples with nodular morphology, having spheres of thermoplastic dispersed in the epoxy matrix, showed water absorption behavior similar to neat epoxy. However, samples with inverted morphology, in which the thermoplastic formed the continuous phase, were more susceptible to water absorption; they exhibited a continued water uptake that could be described by a two‐stage diffusion model. Samples with inverted morphology showed debonding between phases after hydrothermal ageing. Different dynamic‐mechanical behavior has been found for samples that had epoxy matrix and samples with inverted morphology, both before and after hydrothermal ageing. POLYM. ENG. SCI., 47:960–968, 2007. © 2007 Society of Plastics Engineers
Best starting point to comprehensive process safety education
Authors: Ferjencik Milos 
Published: April 2007

AbstractInstruction in process safety began at the Faculty of Chemical Technology, University of Pardubice, in the nineties. In 1994, a course named the Safety Engineering was formed. We aimed to equip our students with a theory that would orientate them in safety problems during their professional lives. Similar to analogous courses at other universities, the Safety Engineering course tends to follow basic steps of the quantitative risk analysis (QRA). An accident analysis and two basic notions—a system and a hazard—were selected as starting points of the course.But after a few years of experience we felt that the Safety Engineering course did not represent exactly what the majority of our students needed. Although the concept of risk analysis represents a fundamental part of any process safety theory, there is another concept that seems to be essential for professionals involved in the process industry—safety management. We started to recognize that an introduction into comprehensive process safety education should be divided into two stages. The safety management and the risk analysis should represent focal points of the first and the second stages, respectively. Two stage arrangement of the process safety course seems to suit needs of our students better than the previous scheme. After the idea of division of the process safety course had arisen, a new starting point for the comprehensive safety education had to be found. An old approach of Kletz's on “learning from accidents” showed itself to be suitable to fulfill this role most naturally. © 2007 American Institute of Chemical Engineers Process Saf Prog 26:195–202, 2007