Investigation on the relationship between macropits and wear particles in a gear fatigue process

In order to provide information about the basic processes involved in the wear of metals, a detailed study has been made of a severe type of wear. The particular system chosen was the wear of brass against a harder material under conditions in which the debris produced is metallic. Using radioactivity methods, transfer of metal between the rubbing surfaces was determined concurrently with measurements of the total wear. In experiments at various loads, the relationship between the rates of transfer and wear was studied. Particle-size distributions of the wear debris were obtained and compared with size distributions of the transferred fragments. It is concluded that wear occurs via a layer of transferred metal and that there is no direct production of loose wear particles. The wear process has at least two distinct stages; namely, the removal of metal from the wearing surface by transfer, and the formation of wear debris from the transferred layer on the opposing member. The magnitude of the applied load determines primarily the scale of the phenomena rather than the rate at which they occur.

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Analysis of Fatigue Process of Rubber Vulcanizates

Rubber Chemistry and Technology ◽

10.5254/1.3545829 ◽

1978 ◽

Vol 51 (2) ◽

pp. 201-214 ◽

Cited By ~ 10

Author(s):

H. Hirakawa ◽

F. Urano ◽

M. Kida

Keyword(s):

Energy Loss ◽

Energy Input ◽

Network Chain ◽

Fatigue Process ◽

Filled Rubber ◽

Linear Relationships ◽

Wide Range ◽

Hysteresis Energy Loss ◽

Number Of Cycles ◽

The Relationship

Abstract The relationship between energy-input and hysteresis energy-loss during repeated deformation was analyzed, with gum and filled-rubber vuloanizates. It was recognized that the hysteresis energy-loss decreases more quickly with repeated deformation than the energy-input does. After a number of cycles both the energy-input and the energy-loss approach constant values. When these values are plotted against strain, curves similar in shape are obtained, regardless of the type of rubber. This is because the network chain is well relaxed. A group of the linear relationships between log W and log H was found with respect to N and λ. Examining the parameters, g1, g2, f1 and f2 as functions of N and λ, simple expressions, (4) and (5), were obtained for both the first deformation and after many cycles. At the latter state the hysteresis ratio tends to be constant in the wide range of λ. Finally, the relation between W and H at fatigue break is expressed with the same form of equation proposed by Grosch for the tensile break at the first extension.

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The Relationship between Wear Phenomena and Wear Particles of Cast Iron

Tetsu-to-Hagane ◽

10.2355/tetsutohagane1955.56.9_1245 ◽

1970 ◽

Vol 56 (9) ◽

pp. 1245-1252

Author(s):

Kazuo KITAGAWA ◽

Fumio SEKI ◽

Masuzo UEDA

Keyword(s):

Cast Iron ◽

Wear Particles ◽

The Relationship

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Development of Tire-Wear Particle Emission Measurements for Passenger Vehicles

Emission Control Science and Technology ◽

10.1007/s40825-020-00181-z ◽

2021 ◽

Vol 7 (1) ◽

pp. 56-62

Author(s):

Yoshio Tonegawa ◽

Sousuke Sasaki

Keyword(s):

Emission Factor ◽

Evaluation Method ◽

Wear Particle ◽

Lateral Acceleration ◽

Vehicle Speed ◽

Wear Particles ◽

Tire Wear ◽

Acceleration Force ◽

The Relationship ◽

Road Study

AbstractIn this study, we aimed to develop a new method for measuring tire-wear particles of less than 2.5 μm generated from vehicle use. We also aimed to devise a method for evaluating the emission factor of tire-wear particles. To develop an evaluation method for tire-wear particles, we examined several factors, such as how tire components in airborne particles collected on a sampling filter were measured, the comparison of tire-wear particles obtained in a laboratory study and an on-road study, a method for measuring tire-wear particles using a test vehicle, and a method for evaluating tire-wear mass using a weighting balance. Measurements of tire-wear particles were carried out using the measurement method proposed herein. The amount of tire wear that the particles generated was almost constant in a vehicle speed range of 20–40 km/h but was influenced by a change in lateral acceleration in the range of 0–0.4G. Furthermore, the relationship between the emission of tire-wear particles and the lateral acceleration force can be shown by a quadratic polynomial. We estimated the emission factor of tire-wear particles by applying the relational equation to the speed profile of the JC08 used in Japanese exhaust gas tests. The emission factor of the test tire used in this study was 3.7 mg/km-vehicle. The ratio of the tire-wear particles to tread wear mass was about 3.3% at PM2.5 and 3.7% at PM10.

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Interstellar gas in the central region of the Galaxy

Symposium - International Astronomical Union ◽

10.1017/s0074180900101032 ◽

1967 ◽

Vol 31 ◽

pp. 239-251 ◽

Cited By ~ 3

Author(s):

F. J. Kerr

Keyword(s):

Central Region ◽

Galactic Plane ◽

Neutral Hydrogen ◽

Continuum Emission ◽

Galactic Centre ◽

Interstellar Gas ◽

Hydrogen Recombination ◽

The Galaxy ◽

Centre Region ◽

The Relationship

A review is given of information on the galactic-centre region obtained from recent observations of the 21-cm line from neutral hydrogen, the 18-cm group of OH lines, a hydrogen recombination line at 6 cm wavelength, and the continuum emission from ionized hydrogen.Both inward and outward motions are important in this region, in addition to rotation. Several types of observation indicate the presence of material in features inclined to the galactic plane. The relationship between the H and OH concentrations is not yet clear, but a rough picture of the central region can be proposed.

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The relationship of the scleractinian corals to the rugose corals

Paleobiology ◽

10.1017/s0094837300025707 ◽

1980 ◽

Vol 6 (02) ◽

pp. 146-160 ◽

Cited By ~ 29

Author(s):

William A. Oliver

Keyword(s):

Critical Points ◽

Scleractinian Corals ◽

Convincing Evidence ◽

Early Triassic ◽

Rugose Corals ◽

History Of ◽

The Subject ◽

Relationship Of ◽

The Relationship ◽

Biologic Factors

The Mesozoic-Cenozoic coral Order Scleractinia has been suggested to have originated or evolved (1) by direct descent from the Paleozoic Order Rugosa or (2) by the development of a skeleton in members of one of the anemone groups that probably have existed throughout Phanerozoic time. In spite of much work on the subject, advocates of the direct descent hypothesis have failed to find convincing evidence of this relationship. Critical points are:(1) Rugosan septal insertion is serial; Scleractinian insertion is cyclic; no intermediate stages have been demonstrated. Apparent intermediates are Scleractinia having bilateral cyclic insertion or teratological Rugosa.(2) There is convincing evidence that the skeletons of many Rugosa were calcitic and none are known to be or to have been aragonitic. In contrast, the skeletons of all living Scleractinia are aragonitic and there is evidence that fossil Scleractinia were aragonitic also. The mineralogic difference is almost certainly due to intrinsic biologic factors.(3) No early Triassic corals of either group are known. This fact is not compelling (by itself) but is important in connection with points 1 and 2, because, given direct descent, both changes took place during this only stage in the history of the two groups in which there are no known corals.

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Choosing a Markov blanket

Behavioral and Brain Sciences ◽

10.1017/s0140525x19002632 ◽

2020 ◽

Vol 43 ◽

Author(s):

Thomas Parr

Keyword(s):

Markov Blanket ◽

Target Article ◽

The Relationship

Abstract This commentary focuses upon the relationship between two themes in the target article: the ways in which a Markov blanket may be defined and the role of precision and salience in mediating the interactions between what is internal and external to a system. These each rest upon the different perspectives we might take while “choosing” a Markov blanket.

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Tinkering with cognitive gadgets: Cultural evolutionary psychology meets active inference

Behavioral and Brain Sciences ◽

10.1017/s0140525x19001018 ◽

2019 ◽

Vol 42 ◽

Author(s):

Paul Benjamin Badcock ◽

Axel Constant ◽

Maxwell James Désormeau Ramstead

Keyword(s):

Evolutionary Psychology ◽

Research Program ◽

Active Inference ◽

Innovative Research ◽

Cognitive Faculties ◽

Cultural Evolutionary ◽

The Relationship

Abstract Cognitive Gadgets offers a new, convincing perspective on the origins of our distinctive cognitive faculties, coupled with a clear, innovative research program. Although we broadly endorse Heyes’ ideas, we raise some concerns about her characterisation of evolutionary psychology and the relationship between biology and culture, before discussing the potential fruits of examining cognitive gadgets through the lens of active inference.

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Radiation Damage, Contrast and Statistics in High Resolution Biological Electron Microscopy

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100068291 ◽

1970 ◽

Vol 28 ◽

pp. 260-261

Author(s):

Robert M. Glaeser

Keyword(s):

High Resolution ◽

Particle Flux ◽

Unit Area ◽

Signal To Noise ◽

Resolution Image ◽

High Resolution Image ◽

Pass Through ◽

Counting Statistics ◽

The Relationship ◽

Picture Element

It is well known that a large flux of electrons must pass through a specimen in order to obtain a high resolution image while a smaller particle flux is satisfactory for a low resolution image. The minimum particle flux that is required depends upon the contrast in the image and the signal-to-noise (S/N) ratio at which the data are considered acceptable. For a given S/N associated with statistical fluxtuations, the relationship between contrast and “counting statistics” is s131_eqn1, where C = contrast; r2 is the area of a picture element corresponding to the resolution, r; N is the number of electrons incident per unit area of the specimen; f is the fraction of electrons that contribute to formation of the image, relative to the total number of electrons incident upon the object.

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