bluuebunny/crossref_metadata_2025_split huggingface dataset:
The shear rheology of thin compressed liquid films
Authors: Bair S 
Published: October 2002

Thin liquid films at elevated pressures have a unique property. A sufficiently high shear stress can be generated in steady shear without encountering the thermal softening limit or interfacial slip that it is possible to observe, in low molecular weight liquids, various non-Newtonian effects ordinarily thought to be reserved for high polymers. These include shear thinning, viscoelasticity and cohesive failure. The relevant rheology literature is reviewed. Only the properties of the continuum are addressed here, omitting near-surface effects. Within the last 10 years in particular, both experiment and molecular simulation have shown that many analogies may be made between lubricants and liquid polymers when allowance is made for the much shorter relaxation time of the low molecular weight liquid. Shear thinning, elasticity and liquid failure are all aspects of the shear response of thin films of low molecular weight liquids at elevated pressures.
Full-field interferometric measurement of head-tape contact spacing
Authors: Swain R , Baugh E , Talke F E 
Published: October 2002

Interferometry is the preferred measurement method for the contact spacing of the head-tape interface, due to its ease of use and high accuracy. Full-field techniques provide spacing data at all points in the field of view as opposed to a single measurement point. Dynamic interferometric measurement necessitates the use of a strobed illumination source, and thus prohibits the alteration of the fringe field to resolve the ill-constrained nature of the analysis problem. In addition, the head-tape contact problem is further complicated by the low phase gradient in the region of head-tape contact, which is often large in comparison to the field of view. In this paper two algorithms are compared which do not require alteration of the fringe field and therefore can easily be applied to the dynamic head-tape interface. The first technique is a two-dimensional implementation of a biquadratic fit to the fringe extremes, while the second is a pseudo-spatial heterodyne technique using the two-dimensional Fourier transform. Theoretical implementation and results are presented.
Surface engineering of titanium alloys for wear protection
Authors: Bloyce A 
Published: October 2002

This paper describes the reasons for the generally poor tribological behaviour of titanium alloys. It describes surface engineering processes currently used in the protection of titanium alloy surfaces against wear including plasma spraying, physically vapour-deposited coatings, electrolytic and electroless plating, ion implantation and anodizing. The advantages and disadvantages of the various processes are indicated and typical components treated by these processes are described. Thermochemical processes and energy beam alloying surface engineering processes applied to titanium alloys are described in greater detail. Contemporary research and development in these areas are described, particularly where the objective is the production of surface hardening to depths comparable with those used in conventional transmission materials such as in nitrided steels.
Correction for pressure dependence of the refractive index in measurements of lubricant film thickness with image analysis
Authors: Marklund O , Gustafsson L 
Published: October 2002

The lubricant film thickness between contacting bodies may be determined from interferograms by image analysis. Look-up tables employed in the analysis are obtained from calibration interferograms of contacts of bodies of known shape. Calibration and measurement interferograms are, however, obtained under different pressure conditions and, since the refractive index of lubricants is pressure dependent, the use of look-up tables can introduce significant errors (in the range of 10 per cent). In this paper it is shown that a straightforward correction for this error is available. In an iterative procedure the uncorrected film thickness is first determined through looking up tables. This allows the pressure distribution over the contact to be calculated and a corrected refractive index may then be obtained. The corrected refractive index in turn allows a corrected film thickness to be calculated. This procedure can be followed iteratively. After two iterations the corrections have been found to be of the same order as the resolution yielded by the method, as has been implemented.
The modelling and simulation of vehicle handling Part 4: Handling simulation
Authors: Blundell M V 
Published: October 2002

This is the last in a series of four papers (Parts 1 to 4) looking at the application of computer-based analysis methods to model vehicles and simulate vehicle handling. The material contained in these papers is based on a study carried out in order to investigate the influence of suspension and tyre modelling on the outputs predicted by vehicle handling simulations. The papers deal with analysis methods, vehicle modelling, tyre modelling (which appeared in the previous two Issues) and handling simulation. In this paper an example of a vehicle handling simulation based on a high-speed lane change manoeuvre is presented. The effects of suspension modelling on the accuracy of simulation outputs is discussed on the basis of results obtained using the four vehicle models described in Part 2 of this series. Measured outputs such as lateral acceleration and roll angle are compared with measurements taken from the vehicle during the same manoeuvre on the proving ground. The influence of the tyre models described in Part 3 on the simulation outputs is shown. The effects of vehicle and tyre modelling on computer simulation time are also summarized. The paper concludes by demonstrating how a simple vehicle and tyre model can be used to carry out sensitivity studies varying vehicle and tyre design parameters.
A study of the effects of the lower index methods on ADAMS sparse tableau formulation for the computational dynamics of multi-body mechanical systems
Authors: Orlandea N V 
Published: October 2002

This paper studies the effects of reducing the index of the original ADAMS (automatic dynamic analysis of mechanical systems) formulation. For this, a pilot computer program MECH-SIM (MECHanical SIMulations) was developed on the basis of the original ADAMS attributes such as sparse tableau formulation (STF) and backward difference formula (BDF) [1]. The STF implemented in the original ADAMS computer program uses differential and algebraic equations (DAE). In the new formulation it eliminates the three relations connecting the body angular velocities and the angular momentum. It also reformulates the implicit force equations by substituting their functions directly into the corresponding differential equations of motion. The above reduction maintains a reasonable number of equations when the geometric constraints stabilize the velocity and/or the acceleration constraints. A method is found to measure ‘the drift’ allowed by the velocity or acceleration constraints. This permits the use of constraints stabilization only ‘when needed’. Consequently, the BDF error control improves maintenance of the efficiency of the method. The pilot computer program MECH-SIM incorporates these improvements. The program was used to test the numerical accuracy and efficiency on mechanical systems used in agricultural mechanization, industrial equipment and auto suspensions. Hence, such results can be extended to the modern ADAMS computer program.
Efficient modelling and analysis for crankshaft three-dimensional vibrations under firing conditions
Authors: Okamura H , Morita T 
Published: October 2002

The three-dimensional vibrations of an engine crankshaft system under firing conditions were investigated by simple modelling and analysis using the dynamic stiffness matrix method (DSMM). In the analyses, the authors took account of the dynamic behaviour of cylinder block, oil film and torsional damper. To simplify the analyses, the crankshaft was idealized by a set of jointed structures consisting of simple round rods and simple beam blocks of rectangular cross-section. The main journal bearings were idealized by a set of linear springs and dash-pots, and the flywheel was modelled by finite elements. Then the dynamic stiffness matrix (DSM) was derived in closed form for each constituent member. To eliminate the complicated finite element method (FEM) analysis for a cylinder block of complicated structure [1,2], the authors derived the dynamic stiffness matrix from the inverse matrix of the compliance matrix. Here, the compliance matrix was derived in analytical form from the modal parameters obtained from a series of hammering tests. Finally, the dynamic stiffness matrix was constructed for the total engine system consisting of the crankshaft system and the cylinder block. The three-dimensional vibrations of the crankshaft system and cylinder block surface vibrations near the main bearings under firing conditions were calculated for an automobile diesel engine in which five kinds of solid pulley, each with different masses and moments of inertia, and a torsional damper were attached to the crankshaft. The calculated results were compared with the experimental results.
The effects of exhaust gas recirculation on diesel combustion and emissions
Authors: Ladommatos N , Abdelhalim S , Zhao H 
Published: October 2002

An investigation was conducted with the aim of identifying and quantifying the effects of exhaust gas recirculation (EGR) on diesel engine combustion and exhaust emissions. Five effects of EGR were identified and investigated experimentally: the reduction in oxygen supply to the engine, participation in the combustion process of carbon dioxide and water vapour present in the EGR, increase in the specific heat capacity of the engine inlet charge, increased inlet charge temperature and reduction in the inlet charge mass flowrate arising from the use of hot EGR. The experimental methodology developed allowed each one of these effects to be investigated and quantified separately. The investigation was carried out on a high-speed, direct injection diesel engine, running at an intermediate speed and load. A limited number of tests were also conducted in an optically accessible diesel engine, which established the effects of EGR on local flame temperature. Finally, tests were conducted with simulated EGR being used additionally to the engine air supply. This contrasts with the conventional use of EGR, whereby EGR replaces some of the air supplied to the engine. It was found that the first effect of EGR (reduction in the oxygen flowrate to the engine) was substantial and resulted in very large reductions in exhaust NOx at the expense of higher particulate emissions. The second and third effects (participation of carbon dioxide and water vapour in the combustion process and increase in the charge specific heat capacity) were almost insignificant. The fourth effect (higher inlet charge temperature) increased both exhaust NOx and particulate emissions. The fifth effect (reduction in the inlet charge due to thermal throttling) reduced NOx but raised particulate emission. Finally, when EGR was used additionally to the inlet air charge (rather than displacing air), substantial reductions in NOx were recorded with little increase in particulate emission.
Predictions of tumble and turbulence in four-valve pentroof spark ignition engines
Authors: Achuth M , Mehta P S 
Published: October 2002

A predictive model for tumble charge motion and turbulence in four-valve pentroof engines has been developed. The model formulation is based on a mean flow analysis of tumble motion in conjunction with k-∊ turbulence equations. All major phenomena, including fluid shear, affecting mean vortex behaviour and turbulence generation are included. The predictions are made for both intake and compression periods of the engine cycle. The model predictions have been compared with earlier analytical investigations in two engines and are found to be in good qualitative and quantitative agreement. The distinct stages characterizing mean vortex and its turbulence have been identified in this work. Further, the mechanism responsible for turbulence enhancement through tumble has been synthesized and related to these stages. A preliminary parametric study with intake valve lifts and pentroof angles is carried out to demonstrate the capability of the model in design studies. It is revealed that a large-angled pentroof retains significant vortex structures even at top dead centre. In an optimized geometry, these structures may play a role in improving overall mass burn rates. The chamber geometry is found to have a significant influence on bulk motion and turbulence levels at ignition. The intake system, however, influences the formation of tumble vortices during the intake stroke.
Novel Method to Prepare Organosilane Monolayers on Solid Substrate
Authors: Kojio Ken , Tanaka Keiji , Takahara Atsushi , Kajiyama Tisato 
Published: October 2002

Abstract
A novel and convenient method to prepare organosilane monolayers was proposed. Pure water was put onto a cleaned silicon wafer and then a toluene solution of n-trichloro(octadecyl)silane (OTS) was spread on it. X-ray photoelectron spectroscopy and atomic force microscopic observation revealed that an OTS monolayer was successfully formed on the solid substrate after the water was evaporated. The static water contact angle of the silicon wafer covered with the OTS monolayer was 105°. Molecular aggregation states of the OTS monolayer were examined by electron diffraction, Fourier transform infrared spectroscopic, X-ray reflectivity, and grazing incidence X-ray diffraction measurements. The prepared OTS monolayer was in a two-dimensional hexagonal crystalline state at 293 K and alkyl chains of the OTS molecules were oriented normal to the surface. Also, the alkyl chains in the monolayer were highly ordered, although the experimental procedure for the monolayer preparation was quite simple. The development of this novel method to prepare a low energy surface will contribute to the material science as well as having industrial applications.
Reaction of HP(OC6H4NH)2 with n-BuLi and then with EX (E = Me, SiMe3, GeMe3, SnMe3, Cp(CO)2Fe, Cp(CO)ICo; X = Cl, I), Leading to Selective Deprotonation and Substitution
Authors: Kubo Kazuyuki , Nakazawa Hiroshi , Ogitani Yukihiro , Miyoshi Katsuhiko 
Published: October 2002

Abstract
The reaction of HP(OC6H4NH)2 with n-BuLi yielded the amide anion, HP(OC6H4NH)(OC6H4N−), with selective deprotonation at the nitrogen atom. Subsequent treatment of the anion with MeI yielded P-methylated phosphoranes: MeP(OC6H4NH)2 and MeP(OC6H4NH)(OC6H4NMe). In contrast, the reaction of the amide with ECl (E = SiMe3, GeMe3, SnMe3) led exclusively to N-substituted phosphoranes: HP(OC6H4NH)(OC6H4NE) and HP(OC6H4NH)2. In the corresponding reaction with (η5-C5H5)(CO)2FeCl, the anion was converted into a P-metalated phosphorane, (η5-C5H5)(CO)2Fe{P(OC6H4NH)2}, whereas the reaction with (η5-C5H5)(CO)CoI2 yielded an N-metalated phosphorane, HP(OC6H4NH)(OC6H4N{Co(η5-C5H5)(CO)I}]. The reason for such selectivity was discussed.
Isolation, X-ray Structural Characterization, and Reactivities of Diiodosamarium(II) Complexes Bearing Amide Compounds as Ligands
Authors: Nishiura Masayoshi , Katagiri Kosuke , Imamoto Tsuneo 
Published: October 2002

Abstract
The structures of diiodosamarium(II) complexes with amide compounds have been investigated basing on single crystal X-ray structural analyses. The reaction of [SmI2(thf)2] with 2 equivalents of tetramethylurea (TMU) gave [SmI2(thf)2(tmu)2] (1). The three different kinds of ligands in 1 attach to the samarium atom in a trans orientation. [SmI2(thf)2] reacted with 4 equivalents of 1,3-dimethyl-2-imidazolidione (DMI) to afford [SmI2(dmi)4] (2), forming a typical hexa-coordinated octahedral structure. Diiodosamarium complex containing four N,N-dimethylacetamide (DMA) ligands [SmI2(dma)4] (3) was prepared by treatment of [SmI2(thf)2] with 4 equivalents of DMA. The reaction of [SmI2(thf)2] with 6 equivalents of 1,3-dimethyl-3,4,5,6-tetrahydro-2-(1H)-pyrimidinone (dimethylpropyleneurea (DMPU)) gave [Sm(dmpu)6]I2 (4) quantitatively. This complex experiences a unique coordination fashion, in which six DMPU ligands coordinate to the samarium atom to overlap each other. [SmI2(dmpu)3(thf)] (5) was isolated from the reaction of [SmI2(thf)2] with 2 equivalents of DMPU. The reducing ability of these complexes was evaluated by reactions with benzylacetone or 9-haloanthracene. The structural analyses and reactivity studies of these complexes indicate that DMPU and DMA ligands are the most effective among the amide compounds to enhance the reducing ability of samarium diiodide.
Synthesis and Structural Characterization of Di-μ-Phenoxo-Bridged Dinuclear Iron(III) Complexes with Ferromagnetic or Weak Antiferromagnetic Coupling
Authors: Mikuriya Masahiro , Kakuta Yoshihisa , Nukada Ryoji , Kotera Takanori , Tokii Tadashi 
Published: October 2002

Abstract
Dinuclear phenoxo-bridged iron(III) complexes with N-salicylidene-2-hydroxy-5-bromobenzylamine (H2La), N-salicylidene-2-hydroxy-5-chlorobenzylamine (H2Lb), and N-salicylidene-2-hydroxybenzylamine (H2Lc): [Fe2(La)2(CH3CO2)2] (1), [Fe2(La)2(C6H5CO2)2] (2), [Fe2(La){(CH3)3CCO2}2] (3), [Fe2(La)2{(C6H5O)2PO2}2] (4), [Fe2(La)2(CH3COCHCOCH3)2] (5), [Fe2(Lb)2(CH3CO2)2] (6), and [Fe2(Lc)2(CH3CO2)2] (7), have been synthesized and characterized by measurements of the infrared and electronic spectra as well as the magnetic susceptibilities. Single-crystal X-ray analysis has revealed that all of the complexes are dinuclear iron(III) complexes having a dinuclear iron(III) core bridged by two phenoxo-oxygen atoms of the Schiff-base ligands. The magnetic-susceptibility data show that a ferromagnetic interaction is operative within a dinuclear core in 1–4, 6, and 7 with J values ranging from 0.17(5) to 1.56(15) cm−1, whereas an antiferromagnetic coupling is operative in 5 with a J value of −9.24(6) cm−1. The magnetic properties are discussed in relation to the crystal structures.
Novel Chiral Fluorescent Labeling Reagent —4-Substituted 7H-benzo[de]benzoimidazo[2,1-a]isoquinolin-7-ones—
Authors: Nakaya Ken-ichi , Funabiki Kazumasa , Shibata Katsuyoshi , Matsui Masaki 
Published: October 2002

Abstract
(R)-4-(2-Hydroxy-1-phenylethylamino)-7H-benzo[de]benzoimidazo[2,1-a]isoquinolin-7-one was used as a fluorescent labeling reagent for Naproxen. The excitation and emission maxima of this reagent were observed at λ 453 and 508 nm in acetonitrile, respectively. This reagent reacted with racemic Naproxen in the presence of dicyclohexylcarbodiimide to afford the corresponding diastereomers, which were nicely separated in HPLC. The detection limit (S/N &gt; 3) of Naproxen was ca. 5 fmol.
Channel selection methods for Infrared Atmospheric Sounding Interferometer radiances
Authors: Rabier Florence , Fourrié Nadia , Chafäi Djalil , Prunet Pascal 
Published: October 2002

AbstractAdvanced infrared sounders will provide thousands of radiance data at every observation location. The number of individual pieces of information is not usable in an operational numerical weather‐prediction context, and we have investigated the possibilities of choosing an ‘optimal’ subset of data. These issues have been addressed in the context of optimal linear estimation theory, using simulated Infrared Atmospheric Sounding Interferometer data. Several methods have been tried to select a set of the most useful channels for each individual atmospheric profile. These are two methods based on the data resolution matrix, one method based on the Jacobian matrix, and one iterative method selecting sequentially the channels with largest information content. The Jacobian method and the iterative method were found to be the most suitable for the problem. The iterative method was demonstrated to always produce the best results, but at a larger cost than the Jacobian method. To test the robustness of the iterative method, a variant has been tried. It consists in building a mean channel selection aimed at optimizing the results over the whole database, and then applying to each profile this ‘constant’ selection. Results show that this ‘constant’ iterative method is very promising, with results of intermediate quality between the ones obtained for the optimal iterative method and the Jacobian method. The practical advantage of this method for operational purposes is that the same set of channels can be used for various atmospheric profiles. Copyright © 2002 Royal Meteorological Society.
Saudi Arabia: Petroleum Industry Review
Authors: Shammas Pierre 
Published: October 2002

A comprehensive review is provided of Saudi Arabia's petroleum industry covering oil and gas exploration and production, refining, oil and gas trade, marketing and Saudi overseas investments. Profiles of key Saudi decision makers are provided. A statistical appendix includes data from the start of oil production in Saudi Arabia in 1938. Part I Geological potential Part II The Saudi energy economy Part III Production capacity Part IV The oil refining sector Part V Exports and logistics Part VI Overseas petroleum industry investments Part VII The decision makers Part VIII Statistical Appendix; Reserves, Production, Exports, Prices 1950 to 1999.
Sound Insulation of Multi-Storey Houses — A Summary of Finnish Impact Sound Insulation Results
Authors: Sipari Pekka 
Published: October 2002

Evidently a wooden house can be built so that modern requirements for both airborne and impact sound insulation are met with sufficient margins. However, low-frequency impact sounds produced by walking may be either audible to the building occupants or felt by them as non-audible vibrations. It is clear that the present rating methods and also perhaps the tapping machine are inadequate where wooden floors are concerned, because the results may be subjectively confusing. The present situation, where internationally there are several rating systems leading to different numerical results for the same building element, needs to be addressed. Existing methods should be developed into a single international method covering all types of floors. The question of how to rate low-frequency (32-100 Hz) footfall noises, which may not be simulated adequately by a tapping machine and rated with present methods, must be considered as a special problem separate from the general rating system. It is generally recommended to add to the mass and stiffness of the wooden floor (for example, by adding a concrete layer) to improve its overall vibration and impact sound insulation behaviour. Such floors are believed to better satisfy the requirements of building occupants.