bluuebunny/crossref_metadata_2025_split huggingface dataset:
Improvement of the bond strength of 4‐META/MMA‐TBB resin to collagen‐depleted dentin
Authors: Soeno Kohyoh , Suzuki Shiro , Taira Yohsuke , Atsuta Mitsuru 
Published: March 2005

AbstractIt has been reported that the tensile bond strength between the 4‐META/MMA‐TBB resin and dentin pretreated with 10% citric/3% ferric chloride solution decreased after immersion in water for 2 years. The current study investigated the effect of an experimental dentin conditioner on the bonding of 4‐META/MMA‐TBB resin to dentin after thermocycling. The experimental conditioner was an aqueous solution of 10% ascorbic acid and 5% ferric chloride (Exp). Human teeth were prepared to expose flat dentin surfaces. These were treated sequentially with 40% phosphoric acid, 10% sodium hypochlorite, and the experimental conditioner. A commercially available dentin conditioner, an aqueous solution of 10% citric/3% ferric chloride (10–3) was used for a control group. Stainless steel rods were bonded to the pretreated dentin surfaces with the use of the 4‐META/MMA‐TBB resin. Tensile bond strengths were determined after 0, 5,000, 10,000, 20,000 themocycles. All data were analyzed by ANOVA, and differences among groups were analyzed by Duncan's new multiple range test (n = 10, p < 0.05). The experimental group showed no significant decrease in bond strength through 20,000 thermocycles, while the control group exhibited significant decrease after 10,000 thermocycles. Mean bond strength of the experimental groups were significantly higher than those of the control group at both 10,000 and 20,000 thermocycles. A hybrid layer could not be identified in SEM micrographs of the experimental groups. 10–3‐conditioned specimen SEMs displayed crack formation between the adhesive resin and a hybrid layer. The experimental dentin pretreatment improved the bond strength of a 4‐META/MMA‐TBB resin to human dentin compared to 10–3 treatment after thermocycling. © 2004 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater 73B: 104–108, 2005
New parallel software (P_Anhar) for anharmonic vibrational calculations: Application to (CH3Li)2
Authors: Gohaud Neil , Begue Didier , Darrigan Clovis , Pouchan Claude 
Published: March 2005

AbstractWe present the development of a new parallel computer code (P_Anhar_v1.0) to calculate the vibrational spectrum of medium size molecules using a variational algorithm. The method is applied to the determination of a complete quartic anharmonic force field (B3LYP/cc‐pVTZ) for methyllithium, leading to a new interpretation of experimental data. © 2005 Wiley Periodicals, Inc. J Comput Chem 26: 743–754, 2005
Prognostic significance of circumferential margin involvement in rectal adenocarcinoma treated with preoperative chemoradiotherapy and low anterior resection
Authors: Luna‐Pérez Pedro , Bustos‐Cholico EfraÍn , Alvarado Isabel , Maffuz Antonio , Rodríguez‐Ramírez Saúl , Gutiérrez de la Barrera Marcos , Labastida Sonia 
Published: March 2005

AbstractIntroductionHistologic examination of circumferential margins is an important predictor of local and distant relapse in non‐radiated rectal cancer. However, for patients who received preoperative chemoradiotherapy this role has not yet been addressed.MethodsFrom January 1995 to December 1997, 61 patients with rectal adenocarcinoma located between 0 and 10 cm from anal verge with invasion into perirectal fat assessed by rectal ultrasound were included. All patients received 45 Gy + bolus infusion of 5‐FU (450 mg/m2/days 1–5, 28–33 of RT); 4–6 weeks later, surgery was performed. Circumferential margin was assessed (<2 mm was considered as positive). Five‐year survival was calculated by Kaplan–Meier method and comparison of groups with log‐rank test. Multivariate Cox regression analysis was performed to find risk factors affecting local control and survival.ResultsThere were 35 males and 26 females, mean age 60.3 years. Twelve patients (19.7%) had circumferential margin involvement. Median follow‐up was 44 months. Overall local recurrence was observed in 6 of 61 patients (9.8%); in patients without circumferential margin involvement this was 8%, whereas it was 16% in those with circumferential margin involvement (P = 0.33). Distant recurrence was observed in 22% of patients without circumferential margin involvement; conversely, it was 58.3% in those with involvement (P = 0.02). Five‐year survival of patients without circumferential resection involvement margin was 81%, while it was 42% in patients with circumferential involvement (P = 0.006).ConclusionsIn patients with rectal cancer treated by preoperative chemoradiation plus total mesorectal excision (TME) and sphincter saving surgery, circumferential margin involvement is associated with high incidence of distant recurrence and cancer‐related death. J. Surg. Oncol. 2005;90:20–25. © 2005 Wiley‐Liss, Inc.
Determination of the acaricide fenbutatin oxide in water samples by automated headspace‐SPME‐GC/MS
Authors: Devos Christophe , Moens Luc , Sandra Pat 
Published: March 2005

AbstractThe analysis of the acaricide fenbutatin oxide (FBTO) having a molecular weight of 1052.66 g mol–1 in water samples by capillary GC/MS after in‐situ derivatization with sodium tetraethylborate (NaBEt4) and headspace‐SPME enrichment is described. Automated SPME is performed at 80°C for 30 min. Detection is carried out in the ion monitoring mode with deuterated triphenyltin (TPhTd15) as internal standard. Good linearity (R 2 = 0.9993) was obtained in the dynamic range 20 to 1000 ng L–1 with a limit of detection of 16 ng L–1 (LOD at 3 S/N ) and a limit of quantitation of 50 ng L–1 (LOQ at 10 S/N ). Intra‐day RSD% for n = 6 was 8.9 at the LOQ level.
Coupling erosion, vegetation and grazing
Authors: Thornes J. B. 
Published: March 2005

AbstractThis paper argues for the replacement of the carrying capacity approach with an approach that emphasizes the stability conditions of the erosion–vegetation–grazing system. Using digital simulation, it is shown that the vegetation stability (temporal and spatial) is a function not only of rainfall, but also of the non‐linear behaviour of the system through its interactions and through the characteristics of the vegetation in determining response to rainfall. A by‐product is the emergence of erosional hot‐spots (bare patches in the vegetation cover). Some implications for grazing management are briefly discussed. Copyright © 2005 John Wiley & Sons, Ltd.
Combining GIS and stochastic simulation to estimate spatial patterns of variation for lead at the Lousal mine, Portugal
Authors: Reis A. P. , Da Silva E. Ferreira , Sousa A. J. , Matos J. , Patinha C. , Abenta J. , Fonseca E. Cardoso 
Published: March 2005

AbstractLousal is one of the many massive sulphide deposits of the Iberian Pyrite Belt. The mine is closed at present, but the heavy metal enriched tailings remain at the surface in the open air. Applying geostatistics to the diagnosis of this potentially contaminated site we aim to assess the quality of the soil. The uncertainty attached to the unknown concentrations of the contaminant was first modelled by a non‐parametric predictor (indicator kriging), and then taken into account in the prediction of the concentrations at unsampled locations by a method of stochastic simulation (p‐field simulation). At each grid node, theNsimulated values resulting from theNequi‐probable simulations were transformed into probabilities of exceeding a regulatory threshold, which allowed assessment of the quality of the soil. The probability maps were then used to identify contaminated areas within the mining field. Copyright © 2005 John Wiley & Sons, Ltd.
Approaches to landcare—a century of soil conservation in Iceland
Authors: Arnalds A. 
Published: March 2005

AbstractOrganized soil conservation in Iceland began in 1907, as a response to severe land degradation and desertification that was threatening the existence of several communities. During the first 75 years, many of the most threatening areas of accelerated soil erosion were fenced and seeded with sand stabilizers. These projects had a high success rate, halting the advancement of sand dunes and other forms of highly accelerated erosion. However, they were limited in scope, and often concentrated on the symptoms of the problems rather than the underlying causes, such as improper grazing management. On a national scale, not enough was being achieved in mitigating the extensive ecosystem degradation. This period of soil conservation in Iceland was characterized by single‐issue, top‐down approaches, a lack of appropriate incentives for soil conservation and weak laws for protection of the rangelands. During the last two decades there has been a gradual shift to more participatory strategies, community involvement, and ecosystem management for multiple benefits. These changes have greatly increased community involvement in projects, stimulated conservation awareness and improved land use. The ties between agricultural policy and soil‐conservation issues are also being strengthened, especially by linking part of governmental subsidies for sheep production to land‐use factors. Copyright © 2005 John Wiley & Sons, Ltd.
Government policies and land degradation in the Middle East
Authors: Nielsen T. T. , Adriansen H. K. 
Published: March 2005

AbstractThe majority of the Middle East is characterized as arid or semiarid and thus susceptible to degradation or even desertification. This paper evaluates long‐term trends in vegetation productivity in the Middle East by means of satellite imagery and discusses the effects of government policies on these trends. Based on yearly estimates of vegetation productivity derived from NDVI, a temporal linear regression model is fitted, pixel by pixel, and the results express the temporal development of vegetation productivity in the region. The results indicate that large‐scale land degradation is not the overall impression in the study area. Approximately 3 per cent of the total area was found to be affected by a marked decline, but only approximately 1 per cent of the total area is affected by significant decreases in vegetation productivity. Three different areas are selected for an in‐depth analysis of the effect of government policies for the trends seen. The three cases—the newly claimed desert lands in Egypt, the marshes in Iraq, and the restructuring process in Israel—are all areas that have undergone significant changes in terms of vegetation productivity over the last twenty years. The results show that these changes are an outcome of government policies rather than local land use practices and these policies can increase or decrease degradation. Copyright © 2005 John Wiley & Sons, Ltd.
Causes and consequences of the Merriespruit and other tailings‐dam failures
Authors: Van Niekerk H. J. , Viljoen M. J. 
Published: March 2005

AbstractOn the night of 22 February 1994, the 31 m high northern wall of the number four tailings dam of the Harmony Gold mine collapsed. The tailings dam is situated 320 m up‐slope of Merriespruit, a suburb of Virginia in the Free State Goldfields of South Africa. More than 2·5 million tonnes of liquefied tailings ripped through the sleeping mining village. Eighty houses were largely swept away and 200 others were severely damaged. Seventeen people were killed.The failure of this tailings dam shocked everybody who followed the unfolding drama of loss of life and destruction of property in the press. At the inquest following the disaster, the judge called this tailings dam a time bomb that was waiting to explode. For the first time in South African history, processed satellite images were allowed as scientific evidence in court. Together with eyewitness reports, all the evidence pointed overwhelmingly to the cause of the failure as being overtopping. The owner, the operator and six of their employees were subsequently found guilty of negligence and heavy fines were imposed.The Merriespruit disaster provided the State and the mining industry with the impetus to ensure the safe disposal of tailings. It also made the mining industry and all those involved with the design and operation of tailings dams take stock of their management and tailing disposal methods. Copyright © 2005 John Wiley & Sons, Ltd.
TiN‐Particle reinforced alumina for unlubricated tribological applications mated with metallic counterbodies
Authors: Poser K. , Rohde M. , Schneider J. , Zum Gahr K.‐H. 
Published: March 2005

AbstractWith respect to the application in unlubricated friction systems like dry clutches a commercially available, slightly porous monolithic alumina was modified using laser irradiation by embedding TiN particles. The materials development was carried out by experimental studies and numerical simulation. Temperature and velocity profiles of the molten alumina and the dispersed TiN particles during laser processing were calculated using a finite volume program (PHOENICS). Tribological properties of the modified ceramics were characterized in unlubricated sliding contact with the grey cast iron GJL‐250 and the steel 100Cr6 using a pin‐on‐disc tribometer. Frictional and wear behaviour were analysed at varied sliding speeds. Commercial alumina and silicon carbide ceramics were used as reference materials.The friction and wear behaviour were determined by mechanical interactions, mainly abrasive processes, material transfer and formation of surface layers from densified wear particles, combined with tribochemical reactions. Sliding pairs with the lasermodified multiphase ceramics showed a greater wear resistance and a greater constancy of the friction coefficient with increasing sliding speed compared to the commercial Al2O3 ceramic.
Influence of surface finish and speed on reciprocating sliding wear of laser modified oxide ceramics in aqueous media
Authors: Peter E. , Zum Gahr K.‐H. 
Published: March 2005

AbstractAlumina and zirconia toughened alumina ceramic were surface modified by alloying with a powder mixture consisting of 3Y‐ZrO2 and SiO2 using a CO2 laser. Tribological properties of the obtained multiphase microstructures were studied using a ring‐on‐plate laboratory tribometer under reciprocating sliding contact in the presence of distilled water, aqueous hydrochloric solution (HCl) and caustic soda (NaOH). Commercially available monolithic alumina ceramic (F99.7) and ZTA ceramic (SN80) were used as reference materials. The results showed a strong effect of surface finish and average sliding speed as well as the different media used on friction and wear. The occurrence of temporary friction peaks was connected with tribochemical reactions and initial surface cavities. Laser surface treatment resulted in ceramics of improved machinability and lower wear intensity compared with the commercial ceramics.
Failure assessment of alumina in unlubricated unidirectional sliding contact
Authors: Tyulyukovskiy E. , Huber N. , Kraft O. 
Published: March 2005

AbstractUsual strength and fatigue experiments for ceramic materials determine the failure behaviour at simple stress states with small stress gradients. Recently, ceramics have been also used in applications like gears and pumps because of their outstanding tribological properties compared to metals. The resulting contact loading causes a multi‐axial inhomogeneous stress state with high stress gradients, which have to be considered in the experimental characterisation and failure prediction. A new method for prediction of the contact strength and contact fatigue behaviour of ceramic components under normal, sliding, and cyclic contact loading has been developed [1]. The method is implemented in a fast Contact Design‐Tool (CDT), that works independent from FEM methods and can be used to assess the lifetime and the failure probability of the loaded ceramic. Results obtained from the Contact Design‐Tool for the friction contact of a continuous variable transmission gear [2] show an exponential dependency of the maximum allowed normal pressure in dependency of the friction coefficient of the system. The results indicate, that contact fatigue under spherical loading of alumina is expected only for radii lower than 15 mm.
Interaction between residual stresses and surface defects in alumina ceramics under tribological loading
Authors: Erbacher T. , Beck T. , Vöhringer O. 
Published: March 2005

AbstractIn the presented research work Al2O3 ceramic plates were subjected to frictional and thermal loadings with the main purpose to investigate typical failure mechanisms of ceramic friction components under such loading conditions. This was done by calculating the local temperatures and stresses using the finite element method and subsequently verifying the model developed using experimental results. By conducting residual stress analyses, 4‐point bending tests, ceramographic analyses and fractographic observations on the ceramic components, a detailed interpretation of the crack initiation and propagation was possible.
Investigation of Al2O3‐ and SSiC‐ceramic under lubricated, reciprocating sliding contact and cavitation erosion
Authors: Dulias U. , Zum Gahr K.‐H. 
Published: March 2005

AbstractTribological performance of alumina and silicon carbide ceramics as well as of the hardened steel 100Cr6 for reference was studied during reciprocating sliding and cavitation erosion in isooctane as substitute of gasoline and in distilled water. It was the aim to characterize effects of surface finish of the specimens and the liquid media on friction, resistance to sliding wear and cavitation erosion. Sliding wear tests were run on the self‐mated ceramics and ceramic/steel pairs under conditions of boundary lubrication using a laboratory tribometer with cylinder‐on‐plate geometry. Vibratory cavitation erosion tests were conducted according to ASTM G 32‐92.High initial surface roughness of coarse ground specimens led to a distinct running‐in period during sliding contact with a transition from high to low values of friction coefficient and wear intensity. Incubation time was reduced with increasing surface roughness in the cavitation tests. Depending on the materials investigated, the type of liquid media showed strong effects both during reciprocating sliding and cavitation erosion.
Advanced probabilistic tools for the uncertainty assessment in failure and lifetime prediction of ceramic components
Authors: Roudi S. , Riesch‐Oppermann H. , Kraft O. 
Published: March 2005

AbstractReliability analysis of ceramic components under stationary or transient loading is generally performed on the basis of a Finite Element stress analysis from which the failure probability according to the multi‐axial Weakest Link theory is calculated with the help of a suitable post‐processing routine. We use the STAU post‐processing routine and the general purpose Finite Element code ABAQUS. Due to scatter in the material parameters, the resulting failure probability is also prone to statistical uncertainties. We present a method of assessing this scatter using so‐called resampling simulation methods. We obtain confidence intervals for the failure probability. For demonstration, the effect of pooling (i.e. grouping of results from different experiments by suitable scaling procedures) on numerical result and scatter of failure probability is shown for fracture of four‐point‐bending specimens. A more applied example deals with a ceramic component in a clutch test bench under thermo‐mechanical frictional loading. For the assessment of the underlying data base uncertainties, Bayesian credibility intervals based on the posterior distribution are presented and provide advantages compared to a conventional maximum likelihood analysis.
Clutches using engineering ceramics as friction material
Authors: Albers A. , Arslan A. , Mitariu M. 
Published: March 2005

AbstractThe experimental and constructive results illustrate that engineering ceramic materials have a high potential in the field of dry running friction systems. According to first estimations, it is possible to build the vehicle clutch 53 % smaller or to transmit up to 180 % higher torque with the same size by an appropriate selection of the system friction pairing and an adequate ceramic design [1, 2]. The friction coefficient characteristic (decreasing friction coefficient above sliding speed) is unfavourable with regard to comfort (self‐induced grab oscillations [3]) of the vehicle clutch. Furthermore, it is important to select the test procedure of the experimental analyses to be as close to the system as possible in order to obtain exact information concerning the target system.
Ceramic components for high pressure gasoline fuel injection pumps
Authors: Häntsche J. P. , Spicher U. 
Published: March 2005

AbstractIn the present project the use of ceramic materials in piston‐cylinder‐systems of high pressure pumps for gasoline direct injection is investigated. The aim is to generate injection pressures of 300 bar with low friction and wear despite of gasoline's poor lubricity and low viscosity. The high resistance of ceramic materials against wear is used to realise these aims.
Continuously variable transmission (CVT) with ceramic components
Authors: Albers A. , Stuffer A. , Bernhardt J. 
Published: March 2005

AbstractContinuously Variable Transmissions (CVTs) are a powerful alternative to automatic gearboxes for passenger cars. Some of these CVTs transmit the power via traction forces through highly loaded lubricated contacts. The aim of the presented work is to increase the capability of this system by means of appropriate engineering ceramics. The modifications are investigated on a machine element test bench. The necessary new tools for the design process and the configuration of the test bench are presented. Measurements show that the desired improvements can be achieved by using engineering ceramics but lifetime requirements have not been met yet.
Development of sialon ceramics for lubricated sliding applications
Authors: Holzer S. , Häntsche J.P. , Spicher U. , Badenheim D. , Oberacker R. , Hoffmann M. J. 
Published: March 2005

AbstractMicrostructural design and characterization of mechanical as well as tribological properties of sialon ceramics are the aim of this work. A potential application for these materials are fuel injection pumps for gasoline engines. The currently used metal parts face severe tribological damage with increasing pumping pressures and thus a replacement is needed. Sialon ceramics offer a wide variety of compositional parameters which allow to tailor microstructure and mechanical properties in order to meet the tribological requirements. Since phase boundaries in the sialon system shift depending on the additive elements used, investigations of the phase relations have been performed for two different sintering additives in order to gain informations about reasonable starting compositions. Then, the ratio of the sialon modifications, the amount of grain boundary phase and the grain morphologies have been correlated with the initial composition and the amount of sintering additives. For high hardness values an increase of the fraction of the α‐sialon modification in mixed α/β‐sialon materials is beneficial. The fracture toughness can be raised by promoting growth of elongated grains. It can be done either by achieving higher β‐sialon fractions in mixed α/β‐sialon ceramics or by sintering with an excess of additive in pure α‐sialon materials. Under lubricated sliding with isooctane, sialon ceramics showed a more advantageous behaviour with regard to friction coefficients and wear than commercial silicon nitride and coarse‐grained alumina.