bluuebunny/crossref_metadata_2025_split huggingface dataset:
Comparison of water measurement results in polyol ester‐based lubricating fluids determined by the coulometric karl fischer method and a thin‐film polymer capacitive water sensor
Authors: Farooq Kal , Fowler Rob 
Published: July 2006

AbstractField samples of MIL‐PRF‐23699 and DOD‐L‐85734, both polyol ester‐based fluids, were evaluated for water concentration by the coulometric Karl Fischer (KF) method according to ASTM D 6304 and with a prototype thin‐film polymer capacitance‐based sensor at Naval Air Systems Command (NAVAIR). The NAVAIR KF results showed a consistent negative bias, 190 ppm on average, compared to the results obtained with the water sensor. Since the calibration of the water sensor was performed by the sensor manufacturer using a different KF instrument and reagent/co‐solvent system, the ∼190 ppm negative bias probably reflects the difference in KF results between sensor manufacturer and NAVAIR. A limited round robin test, involving several laboratories using different instruments, reagents, solvents, and techniques, showed that water concentrations determined by the KF method can vary significantly from laboratory to laboratory. A larger round robin test was conducted to assess more accurately the variability in water measurement results. The results of the two round robin tests show that the particular KF instrument, reagents/solvents, and procedures being utilised by the various participating laboratories lead to a KF measurement variability of 20–30% for polyol ester‐based lubricating fluids. The results show that it is possible to obtain ∼190 ppm difference, observed between the water sensor and KF measurements at NAVAIR, between two laboratories. The results of the round robin tests showed a maximum repeatability of 9%. The significant difference between the repeatability and reproducibility indicates that there is potential for improved reproducibility of KF measurements through standardisation of, for example, instrument type, reagent/solvent system, test method, and laboratory procedure. Further work is required to determine the optimum KF test parameters for polyol.
Scratch properties of poly(methyl methacrylate) surfaces: The time‐temperature dependence of friction and hardness
Authors: Gauthier C. , Schirrer R. 
Published: July 2006

AbstractViscoelastic‐viscoplastic behaviour is usually not taken into account in models describing the scratch properties of polymeric surfaces. In the case of a standard indentation test with stationary tip, the elastic‐plastic boundary and the boundary of the region being subjected to hydrostatic pressure beneath the tip are understood. Such well‐known models have been used in this study to understand the geometry of the groove left on the surface of a viscoelastic‐viscoplastic body by a moving diamond tip. A new apparatus was built that can control the velocity of the tip over the range 1 μm/s to 15 mm/s, at several different temperatures from −10 to +100°C. The material used was a commercial grade of cast poly(methyl methacrylate) (PMMA). The normal and tangential loads and groove size were used to evaluate the dynamic hardness, which behaved like a stress‐ and temperature‐activated process. The values for the activation energy and volumes of the dynamic hardness and of the interfacial shear stress were in good agreement with the mechanical properties usually attributed to PMMA.
Analysis of microstructure and wear of ZnA112Pb alloy used in low‐speed bushing applications
Authors: Jingpei Xie , Wenyan Wang , Yinmin Tu , Aiqin Wang 
Published: July 2006

AbstractWear experiments on ZnAl12Pb alloy and Pb‐based Babbitt alloy (Zch PB16‐16‐2) have been carried out under identical conditions. The wear behaviour of the alloys has been investigated using scanning electron microscopy and surface profile analysis. The results show that ZnAl12Pb alloy is a good material for bushing or bearing applications, and the wear resistance of ZnAl12Pb alloy is better than that of Pb‐based Babbitt alloy.
Improving the wear life of a cocoa spray‐drying unit
Authors: Arda T. , Salman S. , Yukler I. , Unal H. 
Published: July 2006

AbstractIn the chocolate production process, the moisture content of ground cocoa is removed in a spray‐drying unit, in which wet cocoa is pumped through a high‐pressure pump. Wear occurs in this high‐pressure pump, which can cause problems in the system. Originally, valves and beds were made of AISI 316 Ti austenitic stainless steel, and their average wear life was less than 280 h, obviously too short for use in industrial production. The aim of the research reported in this paper was to investigate ways to increase the wear life of these parts. In this respect six different materials were tested. Valves and beds were produced from four different steels and two powder metals. The steel parts were hardened by heat treatment. All the parts were electroplated with CrN or TiN. Wear life tests were carried out, and it was shown that AISI M2 high‐speed steel valves and beds gave the longest wear lives.
Comparison of vickers V‐104C and 20VQ5 vane pump wear rates for various water‐glycol hydraulic fluids
Authors: Totten George E. , Webster G. M. , Bishop Roland J. 
Published: July 2006

AbstractWork is currently under way within the ASTM D.02 N.07 ‘Hydraulic Fluid Testing’ Committee to evaluate the potential of replacing the Vickers V‐104C vane pump with a newer, more current model 20VQ5 vane pump for use in an updated ASTM D 2882 standard and other national standards. All the round robin work conducted within the Committee thus far has involved the use of non‐aqueous hydraulic oils. Although there are some significant inter‐laboratory reproducibility problems, it appears that the overall ranking of these hydraulic oils by most laboratories appears to be consistent. To further evaluate the potential utility of replacing the Vickers V‐104C pump with the 20VQ5 pump, a series of different water‐glycol hydraulic fluid formulations with significantly different wear rates were evaluated using a ‘modified’ ASTM D 2882 testing procedure. The results showed that expected catastrophic pump failures, which occurred with the V‐104C pump, not only did not occur with the 20VQ5 pump, but the relative orders of wear rates for some of the fluids were also different.
Lubrication in helical gears
Authors: Mordukhovich G. , Anderson N. 
Published: July 2006

AbstractIn this paper, a method to determine elastohydrodynamic film thickness in helical gears is developed by combining the Dowson‐Higginson elastohydrodynamic lubrication (EHL) formulation with helical gear geometry and kinematics. Comparisons are made with traditional gear film thickness models. This analysis is then used to characterise the film thickness and lambda ratio in an automotive planetary gearset. Methods to measure surface roughness in fine‐pitch gears are described.
Molecular dynamics simulation of the contact process in AFM surface observations
Authors: Shimizu J. , Zhou L. , Eda H. 
Published: July 2006

AbstractIn the present work, several molecular dynamics simulations have been performed to clarify dynamically the contact mechanism between the specimen surface and probe tip in surface observations by an atomic force microscope (SFM) or friction force microscope (FFM). In the simulation, a three‐dimensional model is proposed where the specimen and the probe are assumed to consist of monocrystalline copper and rigid diamond or a carbon atom, respectively. The effect of the cantilever stiffness of the AFM/FFM is also taken into consideration. The surface observation process is simulated on a well‐defined Cu{100} surface. From the simulation results it has been verified that the surface images and the two‐dimensional atomic‐scale stick‐slip phenomenon, just as is the case for real AFM/FFM surface observations, can be detected from the spring force acting on the cantilever. From the evaluation of the behaviour of specimen surface atoms, the importance of the specimen stiffness in deciding the cantilever properties can also be understood. The influence of the probe tip shape on the force images is also evaluated. From the results it can be verified that the behaviour of the specimen surface atoms as well as the solid surface images in AFM/FFM surface observations can be understood using the molecular dynamics simulation of the model presented.
A new method to simulate the elastic interactions in the tribosystems of a multi‐bar mechanism
Authors: Oprisan Cezar , Olaru Dumitru N. , Leohchi Dumitru 
Published: July 2006

AbstractThis paper presents a new method and criterion for predicting the occurrence of the interruption of a kinematic joint contact in a multi‐bar mechanism. The method is based on the elastic interactions in the tribosystems of the joints with imposed clearances. The method was used in a four‐bar mechanism with clearance in the joint formed from the coupler and the rocker. The analytical results were experimentally confirmed by measurement of the acceleration of the rocker.
Comparison of boundary lubrication films formed under four‐ball friction test conditions with different AW/EP Additives‐an X‐ray photoelectron spectroscopy study
Authors: Unnikrishnan R. , Christopher J. , Jain M. C. , Martin V. , Srivastava S. P. 
Published: July 2006

AbstractThe antiwear and extreme‐pressure properties of six different types of additive (molybdenum dialkyldithiophosphate, dibenzyl disulphide, molybdenum dialkyldithiocarbamate, zinc dialkyldithiophosphate, chlorinated paraffin wax, and triaryl phosphate) were evaluated by standard four‐ball friction and wear tests. This was followed by scanning electron microscopy (SEM), X‐ray photoelectron spectroscopy (XPS), and X‐ray photoelectron imaging (XPI) analyses of the worn surfaces to determine the structure of the boundary lubrication film and the mechanism of the tribochemical reaction occurring during the friction process. The presence of the additives in the base oil significantly increased the weld load and drastically reduced the wear‐scar diameter, suggesting antiwear and extreme‐pressure properties of the additives. The enhanced antiwear and loadcarrying capacity of the additive‐containing oils was attributed to the formation of a complex boundary lubrication film formed between the surfaces during the friction process as a result of the tribochemical reaction. The antiwear and extreme‐pressure properties of the additives were explained based on the XPS data. The studies indicated that the lubricating properties of the additives depend on their chemical nature and reactivity with metal surfaces.
Influence of test parameters on tribological measurements ‐ results from international round robin tests
Authors: Woydt Mathias , Ebrecht Johannes 
Published: July 2006

AbstractA series of cooperative interlaboratory tests (‘round robins’) was conducted in 1997, 1998, 1999, 2000, and 2001 by the DIN 51834 Working Group on Tribological Tests in Translatory Oscillation Apparatus. Statistical analysis of these results showed the influence of cleaning solvent, machine model, and evaluation criteria on the tribological properties of the lubricants tested. Coefficients of friction and wear results were ranked according to the effects of ten different cleaning solvents, where isopropanol gave the lowest values and isoparaffin solvents the highest. The effect of machine model on coefficients of friction varied from about 0.2 to 0.9% of the average. Wear results were not affected. The tests also showed that the seizure criteria and methods of measuring wear required in the test procedure do not provide a suitable measure of the tribological properties of certain lubricants.
Approximate Formula for the Contact between Truncated Surfaces and Frictional Characteristics of a Journal Bearing in Mixed Lubrication
Authors: Nonogaki M. , Nakahara T. 
Published: July 2006

AbstractThis paper presents an approximate formula for the contact of a non‐Gaussian distribution of truncated surfaces, which is useful for mixed lubrication theory, and gives a method for the determination of the truncation parameters in this formula from a measured roughness profile. Using this approximate formula for a contact, the approximate formula for the friction coefficient of a journal bearing in mixed lubrication, which was previously proposed by the authors, is modified for truncated surfaces, and the frictional characteristics are demonstrated for various parameters of truncated roughness using the modified formula.
Optimisation of Industrial Tribological Systems with the Pin‐on‐Disc Tribometer Method
Authors: Randall N. X. 
Published: July 2006

AbstractThe purpose of tribology is to improve the service life and efficiency of machines and their elements. This paper describes certain tests that can be done on a modified pin‐on‐disc apparatus to match in‐service conditions more closely. The three examples considered incorporate a liquid heating function, a reciprocating modification to allow for linear sliding rather than circular sliding, and a modification to allow the simulation of different lubrication regimes.
Influence of lubricant on gear failures — test methods and application to gearboxes in practice
Authors: Michaelis Klaus , Hoehn Bernd‐Robert , Oster Peter 
Published: July 2006

AbstractBase oil type, oil viscosity, and additive type and content have a strong influence on typical gear failures. As it is not possible to quantify the influence of a lubricant on load‐carrying capacity simply from a knowledge of the physical or chemical oil data, many test methods have been developed for the evaluation of mechanical—technological lubricant properties. Simple low‐cost bench test methods often show poor correlation with practice. From both experience and systematic investigation, it can be seen that testing of gear lubricants can be performed adequately only in gear test rigs using specified test gear geometry.The standard FZG back‐to‐back gear test rig has been developed over many years and improved for different types of gear failure simulation. The standard FZG oil test A/8.3/90 is widely used for the evaluation of the scuffing properties of industrial gear oils. Automotive gear oils of GL4 level can be tested in the step test A10/16.6R/90, and axle oils of GL5 level in the shock test S‐A10/16.6R/90. For slow‐speed regimes, the C/0.05/90:120/12 wear test can be used. The influence of lubricants on the micropitting performance of gears can be evaluated in the GF‐C/8.3/90 micropitting test. Different pitting tests are available, as single‐stage (PT‐C/9:10/90) or load spectrum (PT‐C/LLS:HLS/90) tests.The aim of this paper is to describe the influence of the lubricant on the different failure modes in gears, how to quantify this effect in adequate test methods, and how to introduce the results of such tests as determining values of the lubricant into load‐carrying capacity rating methods.
Vacuum tribological behaviour of self‐lubricating quasicrystalline composite coatings
Authors: Garc de Blas F. J. Ía , Román A. , de Miguel C. , Longo F. , Muelas R. , Agüero A. 
Published: July 2006

AbstractHigh‐temperature‐resistant self‐lubricating coatings are needed in space vehicles for components that operate at high temperatures and/or under vacuum. Thick composite lubricant coatings containing quasicrystalline alloys as the hard phase for wear resistance can be deposited by a thermal spray technique. The coatings also contain lubricating materials (silver and BaF2CaF2 eutectic) and NiCr as the tough component. This paper describes the vacuum tribological properties of TH103, a coating of this type, with a very good microstructural quality. The coating was deposited by high‐velocity oxygen fuel spraying and tested under vacuum using a pin‐on‐disc tribometer. Different loads, linear speeds, and pin materials were studied. The pin scars and disc wear tracks were characterised using a combination of scanning electron microscopy and energy dispersive spectrometry. A minimum mean steady friction coefficient of 0.32 was obtained when employing an X750 Ni superalloy pin in vacuum conditions under 10 N load and 15 cm/s linear speed, showing moderate wear of the disc and low wear of the pin.
Power allocation and call admission control in multi‐class traffic DS‐CDMA systems with imperfect power control
Authors: Park Min Kyu , Oh Seong Keun , Lee Chaewoo 
Published: July 2006

AbstractWe deal with power allocation (PA) and call admission control (CAC) under imperfect power control (IPC) in the reverse link of direct sequence‐code division multiple access systems for supporting multi‐class traffic. First, we briefly review the optimum PA scheme under perfect power control (PPC) and the CAC scheme subject to an outage constraint on the total composite received power. Then, we analyze the outage degradation due to the power control error when the optimum reference power levels under PPC are used. In order to mitigate the outage degradation, we would modify the reference power levels by incorporating a call dropping strategy and an outage‐lowering strategy into the optimum PA scheme under PPC. Also, we derive a constraint inequality to determine the reverse link capacity under IPC. Finally, through numerical analyses, we compute the modified reference power levels under IPC and evaluate the reverse link capacity under IPC. Copyright © 2006 John Wiley & Sons, Ltd.
Characteristics of sensory DRG neurons innervating the wrist joint in rats
Authors: Kuniyoshi Kazuki , Ohtori Seiji , Ochiai Nobuyasu , Murata Ryo , Matsudo Takashi , Yamada Toshiyuki , Ochiai Satoko Shiozawa , Moriya Hideshige , Takahashi Kazuhisa 
Published: July 2006

AbstractBackground: Wrist pain can be the result of trauma, or inflammatory processes such as arthritis or synovitis. There is evidence that sensory nerve fibers are present in the wrist joints of animals and humans; however, the sensory innervation pattern of the wrist, as well as the types of nerves innervating it, have not been clarified. The purpose of this study was to characterize the types of sensory dorsal root ganglion (DRG) neurons innervating the wrist joint in the rat.Methods: In this study, retrograde neurotransport was combined with lectin affinity histochemistry and immunohistochemistry to characterize DRG neurons innervating the wrist joint in rats. We used 3 markers: calcitonin gene‐related peptide (CGRP) as a marker of small, peptide‐containing neurons associated with inflammatory pain; the glycoprotein binding the isolectin from Griffonia simplicifolia (IB4) for small, non‐peptide‐containing neurons related to transmission of pain following nerve injury; and neurofilament 200 (NF200) for small and large myelinated fibers. IB4‐binding and CGRP‐containing neurons are typically involved in pain sensation, whereas NF200 is associated with pain and proprioception.Results: Neurons innervating the wrist joints, retrogradely labeled with fluoro‐gold (FG), were distributed throughout DRGs from C6 to T1. Of all of the FG labeled neurons, the percentage of NF200 immunoreactive (IR) neurons and CGRP‐IR neurons were 26% and 45%, respectively. The percentage of IB4‐binding neurons was 3%, significantly less than the ratio of CGRP‐IR neurons to the total FG labeled neurons.Conclusion: Under physiological conditions in rats, DRG neurons transmit several types of sensation from the wrist joint including proprioception and pain. Most of the labeled neurons were CGRP‐IR peptide containing neurons. It is likely that these neurons are the predominant afferents for inflammatory pain signals from the wrist. Because peptide‐containing neurons are associated with inflammatory pain, it is likely that the inflammation in the wrist joint causes wrist joint pain.
Relationships between the frequency of farmed Atlantic salmon, Salmo salar L., in wild salmon populations and fish farming activity in Norway, 1989–2004
Authors: Fiske Peder , Lund Roar A. , Hansen Lars P. 
Published: July 2006

Abstract
In Norway, there have been restrictions on salmon farming in several fjords to reduce the potential negative impact on important stocks of wild Atlantic salmon. Little is known about the incidence of escaped farmed salmon in fisheries and broodstocks relative to the extent of fish farming in nearby areas. In this study, we analysed data on the incidence of escaped farmed Atlantic salmon in angling catches and broodstock fisheries in rivers for a 16-year period (1989–2004). These data were weighted using official catch statistics and combined at the county level, and the incidence of escapees was correlated with both the stock of farmed salmon in net pens and the reported number of escapees in different Norwegian counties. Our results indicate a significant positive correlation between the incidence of escaped farmed salmon in the rivers at the county level and the intensity of salmon farming, measured as the number of farmed salmon in net pens, suggesting that protection areas may reduce the impact of escapees in salmon populations nearby.
Blood splash from different diathermy instruments during tonsillectomy
Authors: Hanna B C , Thompson P , Smyth C , Gallagher G 
Published: July 2006

Objective: To compare the potential risk of blood contamination of the surgeon's conjunctiva during tonsillectomy using disposable bipolar diathermy and reusable monopolar diathermy.Design: A prospective, single-blind, randomized, controlled trial.Methods: Elective tonsillectomy was performed using either disposable bipolar diathermy or reusable monopolar diathermy. The operating surgeon wore a ViewsafeTM protective eyeshield which was later examined under an operating microscope by a blinded observer and the number of blood spots counted.Results: One hundred and sixty-eight patients were enrolled. The relative risk of conjunctival contamination of the surgeon using disposable bipolar diathermy was 2.8 times that with reusable monopolar diathermy (chi-squared test, p < 0.0005). A previous history of peritonsillar abscess and additional adenoidectomy were associated with increased blood splatter.Conclusion: The use of disposable bipolar diathermy for haemostasis during tonsillectomy poses a greater risk of conjunctival contamination for the surgeon than using reusable monopolar diathermy.
Early supraglottic cancer: how extensive must surgical resection be, if used alone?
Authors: Dünne A A , Davis R K , Dalchow C V , Sesterhenn A M , Werner J A 
Published: July 2006

Objectives: Two centre based evaluations of oncologic results of endoscopic resection of supraglottic cancer without post-operative irradiation.Patients and methods: Twenty-six patients with clinical T1 (n=5) or T2 (n=21) primary squamous cell carcinomas of the supraglottic larynx and with N0 (n=24) or N1 (n=2) neck disease were treated by endoscopic supraglottic laryngectomy coupled with neck dissection(s). Endoscopic resection was standardized whereas neck dissections (NDs) varied from classical modified radical ND to selective ND of levels I to IV.Results: Pathologically, three T2 patients were upstaged to T3, four N0 patients to N1 and one N2 patient down-staged to N1. Within an average of 42 months, there were no local failures and only one regional failure.Conclusions: Endoscopic resection of T1 and T2 supraglottic cancer without post-operative irradiation achieved good oncological results. No patients with lateralized primary cancers were found to have contralateral cancer on pathological evaluation from bilateral dissections.