Effect Of Cage Research Articles

The Effect of Cage and Roller Slip on the Measured Defect Frequency Response of Rolling-Element Bearings

The paper reports the effect of cage and roller slip on the measured defect frequency response of rolling-element bearings using high-frequency resonance technique (HFRT) as a survelliance module. The differences in theoretically calculated and experimentally determined defect frequencies have been used to identify percentage cage slip and roller slip in various bearings under no-load and load conditions at different speeds of operation. Various defect frequencies and their energy levels are used to monitor the severity of defects and complex response interactions of rolling elements with inner and outer rings of the bearings. It is shown that negative cage and roller slip is predominant at moderate speed under no-load and load operation. Positive slip is significant at high speed under no-load operation. Negative cage and roller slip is indicated by the presence of outer-race linear defect frequency along with rolling-element defect frequency, whereas positive slip is shown by inner race accompanied with rolling-element defect frequencies. Energy levels of identified defect frequencies are greater under no-load as compared to operation under load for new bearings at all speeds of operation. However, for defective bearings, this pattern is reversed at rated and high speeds of operation. In general, percentage negative cage slip is found to be more than the corresponding roller slip and percentage positive cage slip is less than corresponding roller slip. Under load at rated speed, cage and roller slip is minimum for new bearings. However, the slip is still identified by defect frequency response. The investigations reported in the paper may prove to be a potential tool to diagnose the complex response interactions in rolling-element bearings.

Effect of rib cage and abdominal restriction on total respiratory resistance and reactance.

In 14 healthy male subjects we studied the effects of rib cage and abdominal strapping on lung volumes, airway resistance (Raw), and total respiratory resistance (Rrs) and reactance (Xrs). Rib cage, as well as abdominal, strapping caused a significant decrease in vital capacity (respectively, -36 and -34%), total lung capacity (TLC) (-31 and -27%), functional residual capacity (FRC) (-28 and -28%), and expiratory reserve volume (-40 and -48%) and an increase in specific airway conductance (+24 and +30%) and in maximal expiratory flow at 50% of control TLC (+47 and +42%). The decrease of residual volume (RV) was significant (-12%) with rib cage strapping only. Abdominal strapping resulted in a minor overall increase in Rrs, whereas rib cage strapping produced a more marked increase at low frequencies; thus a frequency dependence of Rrs was induced. A similar pattern, but with lower absolute values, of Rrs was obtained by thoracic strapping when the subject was breathing at control FRC. Xrs was decreased, especially at low frequencies, with abdominal strapping and even more with thoracic strapping; thus the resonant frequency of the respiratory system was shifted toward higher frequencies. Partitioning Rrs and Xrs into resistance and reactance of lungs and chest wall demonstrated that the different effects of chest wall and abdominal strapping on Rrs and Xrs reflect changes mainly of chest wall mechanics.

Distortions of ultrasonic field introduced by the rib cage in echocardiography.

In ultrasonic examination of the heart, the anatomy and motion of heart structures can be observed by placing the ultrasonic transducer over an intercostal window adjacent to the sternum. The ultrasonic beam may be reflected, refracted, or scattered from its path by the ribs and soft tissues before reaching the target of interest. This interaction between the tissues and ultrasound beam, which introduces significant changes in ultrasonic beam characteristics, may result in considerable degradation of the lateral resolution of the ultrasonic system, determined largely by the beam width. In this paper, the effect of rib cage on the beam characteristics is examined. It is shown that the rib cage can produce severe distortions of the ultrasonic beam, namely, asymmetry in beam cross-section, alteration in beam diameter, and deflection of the beam from its central path. It is also demonstrated that this distortion is dependent upon transducer diameter, width of the intercostal window, and transducer angulation relative to the breast plate.

Effect of rib cage on the beam profiles of ultrasonic transducers

In multidimensional echo imaging of the heart, the anatomy and motion of the heart structures can be observed by placing the transducer over the intercostal window. The ultrasonic beam may be scattered, reflected or refracted from its path by the ribs and soft tissues between them. Since beam distortion is directly related to the loss of resolution in pulse‐echo imaging systems, an investigation of the effects of these intervening tissues on the ultrasonic beam characteristics may be useful for establishing criteria for selecting suitable transducers in clinical scanning procedures. In order to address this problem, an automated system for rapid mapping of transducer field based on a microcomputer has been developed in our laboratory. In this paper, we will present the initital results on our investigation of the beam distortions produced by the rib cage in terms of 3‐dimensional display of the intensity contours at various distances from the transducer. Also to be discussed is the effect of transducer angulation in relation to the breast plate on the transmitted ultrasonic beam.

Effect of Cage and Floor Rearing; Dietary Calcium, Phosphorus, Fluoride, and Energy Levels; and Temperature on Growing Turkey Performance, the Incidence of Broken Bones and Bone Weight, and Ash

Performance of female large type turkeys was compared in cages of two sizes and in floor pens. Tests were conducted over the period from 8 or 9 through 18 weeks of age. The smaller cages had two birds per cage and the larger 12, both with .14 m2 floor space per bird. Turkeys raised in the smaller cages had smaller metatarsi with less bone ash and showed a higher incidence of broken bones when slaughtered than those raised in floor pens. Those raised in the larger cages had intermediate weights of metatarsi and bone ash and a low incidence of broken bones.Increasing the calcium level of the diet from .82 to 1.00% had no significant effect on the incidence of broken bones. Addition of 50 ppm of fluoride to the diet increased bone ash but did not decrease the incidence of broken bones. Addition of animal fat to the diet increased weight gain and the incidence of broken bones. Increasing diet phosphorus level from .62 to .71% did not affect weight gain or gain/feed ratio, increased bone ash, and decreased broken bone incidence slightly. Increasing the cage size was the only treatment tested that resulted in near elimination of broken bones in caged turkeys.The small cages were located in two rooms with temperature control. The temperature was controlled at 13 and 23 C in one test, at 16 and 26 C in six tests, and at 19 and 29 C in one test. Weight gain was higher at the cooler temperature in all tests. Gain/feed ratio tended to be higher at the warmer temperature with the two lower temperature pairs tested. Weight gain and gain/feed ratio of the female turkeys in cages was of the same order as noted in commercial production in sheds.

Anharmonic force constants of N 2O from matrix infrared spectra

Infrared spectra of 14N 2 16O, 15N 2 16O, 14N 15N 16O, 15N 14N 16O and 14N 2 18O have been measured with the molecule isolated in a solid N 2 matrix. The wavenumbers of the observed fundamentals, overtones and combinations have been used to determine the force constants in an anharmonic force field which included cubic and quartic force constants. The force constants determined from the matrix data have been compared with the corresponding ones determined from the gas-phase spectra including rotational constants. It is concluded that the effect of the matrix cage may be represented by small (a few per cent) perturbations on the intramolecular force constants determined from the isolated molecule in the gas phase.

The Studies of the Cage Effect of Solvents. VI. The Photolysis of Methylazoethane in n-Heptane

Abstract Methylazoethane was photolyzed in n-heptane in order to study the effect of a solvent cage quantitatively; the results obtained were then compared with those for azomethane and azoethane previously studied. By using styrene as a scavenger for radicals, it was demonstrated that a large fraction (90% at −75°C and 58% at 100°C) of a pair of methyl and ethyl radicals formed by the decomposition of a molecule of methylazoethane combines to form propane or disproportionates to form methane and ethylene in an original solvent cage. The ratio of the rate constant for the disproportionation to that for the combination is small, and it decreases with a rise in the temperature, as was previously found for azoethane. The effect of the temperature on the yields of the products of cage reactions in the present work and in the previous work with azomethane and azoethane shows that the combination of ethyl radicals and the cross-combination of methyl and ethyl radicals in a solution require appreciable activation energies, even if that for the combination of methyl radicals is zero.

Studies of the Cage Effect of Solvents. V. The Photolysis of Azoethane in n-Heptane

Abstract The effect of a solvent cage on the photolysis of azoethane in n-heptane was investigated at 366 mμ, in the temperature range from −75 to 99°C. Among the gaseous products, nitrogen served as a measure of the azoethane decomposed. The other gaseous products were n-butane, ethane and ethylene; these three hydrocarbons accounted for ninety per cent of the decomposition at 0°C. The quantum yield of nitrogen was found to decrease with a lowering of the temperature. The value obtained at 0°C was 0.021. In the presence of a sufficient amount of styrene, which was used as a scavenger for ethyl radicals, the yields of the gaseous hydrocarbons were more or less reduced to constant values; from these the ratio of rate constants for the combination and disproportionation of the geminate ethyl radicals formed by the photolysis in a solvent cage was determined to be kcomb⁄kdisp=11.5exp(−371⁄RT). The fraction of ethyl radicals that reacted in these ways in the solvent cage, before escaping it, was dependent on the temperature; it decreased from 0.838 at −75°C to 0.467 at 99°C. In the absence of styrene, the reactions for ethyl radicals that escaped the original solvent cages were inferred to be hydrogen abstraction, addition, combination and disproportionation.

Effect of Cage versus Floor Rearing on Performance of Egg Laying Type Pullets

In previous report, authors suggested that better development of average body weight of chickens was observed in the cage rearing in comparing to the floor rearing, but there were no significant differences on the mortality in growing period among them. It was also found that birds reared in the multiple cage from 11 to 20 weeks of age should have 0.16-0.18m2 of space per bird.In this trial, effects of cage or floor rearing for growing period on performance in egg laying Period were observed. Strain cross of White Leghorns, White Leghorn (_??_ _??_)×Barred Plymouth Rock (_??_ _??_) and White Leghorn (_??_ _??_)×New Hampshire (_??_ _??_) were used. Each strain cross was divided into three groups: the first group was reared in the multiple cage up to 20 weeks of age; the second and third groups were reared in the multiple cage up to 10 and 6 weeks of age respectively, and then were reared on the floor up to 20 weeks of age. At the beginning of 21 weeks, 45 birds of each group and cross were put in the individual laying cages.Age at the first egg laid was the shortest in the first group notwithstanding the cross, though White Leghorn matured later than other two crosses. Differences between rearing methods and crosses were significant at 5% level. Average egg weight of the first group was heavier than those of other two groups. There were no significant differences on egg production and mortality between rearing methods and strain cross.From these results, authors think that multiple cages may be used for rearing of egg laying type pullets throughout the growing period.

Effect of Cage <i>versus</i> Floor Rearing on Performance of Egg Laying Type Pullets

Effect of Cage <i>versus</i> Floor Rearing on Performance of Egg Laying Type Pullets

Studies of the Cage Effect of Solvent. I. Photolysis of Azomethane in n-Hexane

Abstract Azomethane in n-hexane solution has been decomposed by irradiation of 366 mμ over the temperature range −75 to 80°C, in order to study the effect of the solvent cage on the photolysis. The main products have been found to be nitrogen, methane and ethane. The yield of methane increases, but that of ethane, which amounts to 88% of nitrogen at −75°C, decreases with the rise in temperature. The addition of styrene as a scavenger for methyl radicals in an increasing amount suppresses the formation of methane almost completely, while that of ethane is not affected, indicating that ethane is exclusively formed by the cage combination of an azomethane molecule. The formation of methane is explained by the abstraction of the hydrogen atom from a solvent molecule by methyl radicals that have escaped the original cage. The material balance represented as ((1/2)CH4+C2H6)/N2 is nearly 100% below room temperature, but it falls off slightly at higher temperatures; this may be ascribed to addition reactions of methyl radicals. The quantum yield of photolysis is apparently smaller than unity and falls off with a lowering of the temperature; this probably arises from the cage recombination of the initially formed pair of radicals CH3N2 and CH3, though the former radical is very short-lived.

The Visible Absorption Spectrum of Bromine in Solution

The visible absorption spectrum of bromine was measured in n-hexane (a normal solvent) and in concentrated sulphuric acid (at room temperature and at -70� C.), phosphoric acid, and ethanol (at -70� C.) as associated solvents. The absorption continuum at 4150 A. in the gas is displaced slightly to the red in n-hexane although other normal solvents may displace it to the violet. The displacement to the violet is greater in associated solvents, ranging from 650 cm.-l in sulphuric acid to over 2000 cm.-1 in ethanol. The displacement in sulphuric acid glass at -70� C, is nearly double the value at 18� C. The displacements in associated solvents are explained in terms of the effect of the semi-rigid cage of solvent molecules surrounding each bromine molecule, and the assumption of " solvates " is unnecessary and undesirable. The spectra in solution are between 40 and 70 per cent. more intense than in the gas, about double the increase that would be predicted by Chako's treatment of the effect of Lorentz-Lorenz forces. The differences in the shape and Emax between solutions in sulphuric acid at 18� C. and at -70� C. are due to the different statistical distribution of bromine molecules between the vibrational energy levels.