Showing papers by "Ford Motor Company published in 1972"

A debate on the bainite reaction

Abstract: The authors debate three topics central to the controversies which have enveloped the bainite reaction ever since it was first recognized as a distinctive mode of austenite decomposition. These include: “what is bainite?”, “the growth mechanism of the ferritic component of bainite”, and “the sources of bainitic carbide precipitation.” RFH concludes that bainite is the product of a shear transformation. Individual bainite plates are suggested to grow substantially more rapidly than volume diffusion-control allows, but a constraint such as the build-up of volume strain energy limits the extent of their growth. This mechanism of growth ensures extensive supersaturation of bainitic ferrite with respect to carbon. Whether or not carbides precipitate in association with bainite plates and whether the carbide is cementite ore, however, is a complex question in competitive reaction kinetics. New experimental evidence is presented to demonstrate thate carbide precipitated in lower bainite dissolves upon heating above the kinetic-B stemperature in an alloy steel containing 1.5 pct Si. This result is taken to support the existence of the metastable eutectoid reactionγ ⇌ α + e atca 350°C. HIA and KRK define bainite as the product of a nonlamellar eutectoid reaction. On this view, carbide precipitation thus plays an essential, rather than an ancillary role. Development of the Widmanstatten morphology by the ferritic component of bainite is shown to be inessential to the classification of a eutectoid structure as bainite. When this morphology is present, however, it is concluded to grow by the ledge mechanism, without the participation of shear, at rates of the order of or less than those allowed by volume diffusion-control. New experimental evidence is presented to show that the lengthening and thickening kinetics of individual plates within sheaves of upper bainite are consistent with this description. The results of a new calculation indicate that the initial carbon content of bainite plates lies between theα/α + Fe3C) and the extrapolatedα/(α+ γ) phase boundaries, in agreement with expectation from the ledge mechanism of growth.

Carbon Monoxide Balance in Nature

Abstract: Consideration of the steady-state equations for stable carbon monoxide and for radioactive carbon monoxide in the troposphere leads to the conclusion that carbon monoxide is produced at a rate of 5x10(15) grams per year, a value some 25 times greater than the rate of carbon monoxide production from combustion. The concomitant residence time for carbon monoxide is 0.1 year, in agreement with a previous estimate of Weinstock. Hydroxyl radicals are shown to account for both the production of this large amount of carbon monoxide by methane oxidation and for its removal by carbon monoxide oxidation. The average concentration of hydroxyl radicals in the troposphere required to achieve this effect is 2.3x10(6) molecules per cubic centimeter, with a daytime concentration of twice that. Levy and McConnell, McElroy, and Wofsy have deduced concentrations of hydroxyl radicals in the troposphere of the same magnitude from purely photochemical considerations, in support of this model.

Crystal structure of isotactic polypropylene

Abstract: To account for the observed diffraction pattern of a commercial specimen of oriented fibers of isotactic polypropylene in the a modification, the crystal structure is described as belonging to the space group P 21/c but having a certain disorder in the distribution of “up” and “down” chain direction. As a result of this disorder, reflections having the (h + k) sum odd are weaker than in the ideal P 21/c space group, and the structure thus resembles partially the situation in the C 2/c space group where no such order is required or possible. In the specimen studied in this work, best agreement between theory and experiment (R = 0.158) was achieved if it was assumed that in about 25 % of matter the chains were placed in the wrong direction.

The nature of the collagenolytic cathepsin of rat liver and its distribution in other rat tissues.

Abstract: 1. An enzyme present in rat liver extracts degraded insoluble collagen maximally at pH3.5. Collagenolytic activity was more abundant in kidney, spleen and bone marrow and was also present in decreasing concentrations in ileum, lung, heart, skin and muscle. 2. The crude collagenolytic cathepsin was activated by cysteine and dithiothreitol, but not by 2-mercaptoethanol. Iodoacetamide, p-chloromercuribenzoate and 7-amino-1-chloro-3-l-tosylamidoheptan-2-one hydrochloride inhibited the enzyme. Zn(2+), Fe(3+) and Hg(2+) ions were strongly inhibitory, but Ca(2+), Co(2+), Mg(2+) and Fe(2+) ions had little or no effect. EDTA was an activator of the enzyme. Inhibitors of cathepsin B were found to enhance collagenolysis, but phenylpyruvic acid, a cathepsin D inhibitor, inhibited the enzyme. Di-isopropyl phosphorofluoridate had no effect. 3. Collagenolysis at pH3.5 and 28 degrees C was restricted to cleavage of the telopeptide region in insoluble collagen, and the material that was solubilized consisted mostly of alpha-chains. 4. The collagenolytic cathepsin was separated from cathepsins B2 and D by fractionation on Sephadex G-100 and a partial separation from cathepsin B1 was obtained by chromatography on DEAE-Sephadex. 5. The function of the collagenolytic cathepsin in the catabolism of collagen is discussed in relation to the action of the other lysosomal proteinases and the neutral collagenase.

Fuel tank insert for admitting preselected pump nozzles

Abstract: An insert to be positioned within the fuel tank inlet pipe of an automotive vehicle to prevent filling the tank with improper fuels. The insert would permit entry of and delivery from a pump nozzle spout of a predetermined diameter of less, to be used with non-leaded fuels and would preclude entry of and delivery from a larger diameter pump nozzle spout, to be used with leaded fuels. The insert includes a hinged gage having a latch which can be tripped by the smaller diameter nozzle but not by the larger diameter nozzle.

Thermodynamic and Physical Properties of Molten Sodium Polysulfides from Open‐Circuit Voltage Measurements

Abstract: The open-circuit votlage of the cell Na/..beta..-alumina/Na/sub 2/S/sub x//pyrolytic graphite has been measured as a function of temperature and sodium-polysulfide composition. From these data, differential free energy, entropy, and enthalpy values for the potential-determining reaction and the differential free energy of formation for various polysulfide compositions were calculated. The partial differential enthalpy (Hnumber/sub 1/) of adding Na to the polysulfide melt is -47.6 KCAL/MOL independent of melt composition and temperature. The solubility of sulfur in sodium pentasulfide was determined between 280/sup 0/-390/sup 0/C, and the Na/sub 2/S-S phase diagram of Pearson and Robinson was revised in the Na/sub 2/S/sub 2/S range and extended to show the Na-rich border of the miscibility gap. 5 references.

Electromagnetic Hydrodynamics of Liquid Crystals

Abstract: We have developed a set of differential equations which describe the hydrodynamics of a conducting liquid crystal subjected to external electromagnetic fields. The mechanical forces resulting from the interaction of the fields with the liquid are expressed as operations on the Maxwell stress tensor. The use of this description allows a concise statement of the equations of motion. As an example of the validity of the formalism, we rigorously solve the boundary-value problem associated with the Williams domain (vortex) mode in nematic liquids. Using standard constitutive relations, physical boundary conditions, and experimentally measured material $p$-azoxylanisole constants, we quantitatively reproduce the significant experimental observations.

Method of fabricating a precontoured unitized electrical wiring harness

Abstract: A wiring harness comprised of a plurality of conductive wires each encased in a tubular nonconductive thermoplastic sheath and placed in side-by-side alignment, the plurality of conductive wires being precontoured and restrained in such condition by a plurality of transverse hinges formed from said thermoplastic sheathing and interconnecting adjacent wires of said harness. The unitized harness is employed in a wiring system particularly useful in an automotive vehicle; the system has connective blocks for joining the extremeties of said wires with an energy source or for switching purposes, each of said blocks being characterized by contacts effective to penetrate the wire sheathing and make contact with the conductive element, each of said contacts having a portion for receiving remote conductors by simple insertion.

Bumper support and energy absorbing frame system for a motor vehicle

Abstract: This disclosure relates to impact absorbing systems for motor vehicles. In a preferred embodiment, the system includes energy absorbing frame structure and telescopic energy absorbers supporting the vehicle bumper and disposed within the frame front side rails. The frame side rails have corrugated plastically deformable portions. The telescopic energy absorbers function to absorb low level impact loads against the bumper and to support the corrugated frame portions for controlled collapse during high level impact loads.

Carburetor throttle valve positioner

Abstract: One embodiment of a downdraft type carburetor has an idle system discharge port that is straddled by the normal idle speed and closed throttle positions of the throttle valve so as to permit idle speed fuel and air flow in one position and no flow in the other position; a third beyond normal idle, or fast idle speed position is provided for engine startup; another embodiment has a conventional idle system with a transfer port cooperating with the edge of the throttle valve so as to permit normal idle speed fuel and air flow in one position and a less combustible mixture flow in a second position, as well as a third beyond normal idle engine hot start position; the three positions of each embodiment are controled by a servo operatively engaging the throttle valve; the servo operation is controlled by intake manifold vacuum to initially close the throttle valve upon engine shut off, with a subsequent return of the throttle valve to its fast idle position for engine restarting, or to return the throttle valve to a normal idle position upon release of the vehicle accelerator pedal during engine operation.

Detection of OH in the atmosphere using a dye laser

Abstract: Preliminary experiments suggesting the feasibility of using a resonance fluorescence scheme to detect ambient concentrations of OH in the atmosphere (106 molecules/cm3) were carried out using OH concentrations near 1012 molecules/cm3. The P1(1) line of the v = 0 → 1 branch of the lowest electronic transition of OH at 2822 A was resonantly excited with radiation from a doubled dye laser. The subsequent fluorescence from the v = 0 → 0 branch with Δν ≅ 3050 cm−1 was observed to have a fluorescence efficiency of 0.6 × 10−3 in N2 at atmospheric pressure with a 10‐mm partial pressure of H2O. This fluorescence occurs 500 cm−1 away from any strong Raman line in the atmosphere.

Vehicle interior rear view mirror

Abstract: A vehicle rear view mirror the reflective surface of which is a reflective coating on a plurality of vertically extending strips, the lines of intersection of the planes of the strips with the front planar surfaces of the mirror being vertical and the angles which the individual planes of the vertically extending strips make with the planar surface increasing progressively from the center of the mirror towards the side edges of the mirror.

Glass shipping rack

Abstract: A rack for shipping and storing a plurality of individual sheets of glass or the like, and particularly curved automotive glass units. The rack includes resilient brace members which can be adjusted both vertically and horizontally so as to accommodate units of various sizes supported upon edge. The resilient braces and support members have multiplanar surfaces for engaging the units whereby the rack will accommodate a variety of units with different curvatures, dimensions and outlines. Adjustable straps secured to the rack frame at their opposite ends support the top edges of the individual units.

Isokinetic sampling probe

Abstract: A sampling and handling system for the exhaust of an automotive engine whereby emissions flowing through a through-duct are mixed, extracted through an isokinetic probe, and maintained heated until analysis of the sampled gases is completed. A variable speed pump means is utilized to equalize the instantaneous pressure drop through the probe with the instantaneous pressure drop through the exhaust duct.

On vacancy condensation and the origin of dislocations in growth from the melt

Abstract: The formation of dislocations from condensed vacancies has been reexamined. Conditions for transformation of vacancy clusters into dislocation loops are analysed, taking into account an entropy contribution of atoms in the dislocation core. New evidence in the literature for a vacancy concentration beyond that of equilibrium at the advancing solid-liquid interface is used to calculate an excess vacancy concentration trapped in the solid as a function of freezing velocity. This excess leads to an estimation of the nucleation frequency of loops and supports the condensation mechanism as the source for dislocations. The critical stage for dislocation formation in growing crystals is also shown to depend upon the temperature distribution in the solid. Results of this analysis are applied to the formation of dislocations in a general f.c.c. metal, and specifically in lead, aluminium and copper, for which experimental information is available. Striation formation is discussed for these metals; it is co...

Critical flow venturi

Abstract: An apparatus for determining the total mass of exhaust gas constituents emitted from an internal or external combustion engine, the apparatus having a through-flow duct to receive the exhaust gases and into which is introduced dilution air for thorough mixing with the exhaust gases. The apparatus has means for measuring not only the total mixed flow but also the total flow of dilution air introduced to the duct. Unique means is utilized for extracting and measuring a proportional sample of said mixed flow. Collection and measuring apparatus is used to determine the concentration of dilution air constituents as well as the combined concentration of gaseous constituents in the mixed flow. Utilizing the above two flow measurements and the two constituent concentration measurements, the total mass of exhaust gas from the engine is simply determined on a theoretically correct basis.