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131.
132.
A steam-volatile extract, possessing a strong mushroom-like odour, has been isolated from Agaricus bisporus, the cultivated white mushroom of the mushroom grower. The major volatile components present, viz., 3-methylbutanal, 3-octanone, oct-1-en-3-one, 3-octanol, oct-1-en-3-ol, furfural, benzaldehyde, phenylacetaldehyde and benzyl alcohol, were identified by combined gas chromatography-mass spectrometry, and several other components were either positively or tentatively identified. The properties of the mushroom-like odour of oct-1-en-3-one and of the corresponding alcohol in dilute aqueous solution were examined.  相似文献   
133.
For a linear noisy system assume an estimatehat{beta}of the unknown parameter vector was obtained from a certain past data on inputs and outputs of the system. The prediction of the output for any input vectorxis a linear combination ofxandhat{beta}. The question of concern is: For what - values of the inputs would the error in their predicted outputs be the smallest? It is found that they are the inputs which lie on the fitted plane of the orthogonal regression among the past data of the clean inputs.  相似文献   
134.
Attempts have been made to determine the longitudinal crystal modulus for linear polyethylene by studying the change in the 0 0 2 reflection with load for a series of uniaxially oriented films. The specimens examined covered a wide range of draw ratios, and included a number of ultra high modulus films. In low draw ratio specimens, the assumption of homogeneous stress gave a value for the crystal modulus in good agreement with previous work. The results for the ultra high modulus specimens, on the other hand, were more consistent with continuity of strain, although there were still discrepancies which require further study.  相似文献   
135.
A novel technique is described which enables reliable fracture toughness measurements to be made in impact test on relatively small specimens of a tough polyethylene. Composite specimens have been made in which a tough polyethylene is sandwiched between two layers of a more brittle polyethylene. The overall fracture toughness is interpreted on the basis of simple additivity of the strain energy release rate associated with each of the component layers. Brittle plane strain failures were obtained for specimens in which the relative thickness of the layers was varied over a substantial range and the fracture toughness of each layer determined by suitable extrapolation. The fracture toughness of the brittle layer obtained in this way agreed well with direct measurements on that material.  相似文献   
136.
The effect on oxidation of cyclically stressing a low carbon steel was studied at tempera-tures of 500 and 570°C. It was found that if the cyclic strain was above a threshold value which corresponded to the fracture strain of the surface scale, then the oxide growth rate increased both at 500 and at 570°C. The oxide fracture strains under fatigue conditions were found to be in the range 2.7 - 5.1 x 10-4. The mechanism of the process is discussed in relation to oxidation kinetics and the mechanical properties of the growing surface scales.  相似文献   
137.
Yield and fracture of polyethylene have been studied in torsion tests under superposed hydrostatic pressures. Two ductile-to-brittle transitions have been observed. At high strain rates and pressures, a conventional ductile-to-brittle transition was found with increasing strain rate and pressure. A second ductile-to-brittle transition was observed at low strain rates with decreasing strain rate. The yield stress showed a region of low, relatively constant, rate dependence at low strain rates, high temperatures and low pressures and a second region of higher strain-rate dependence at high strain rates and pressures. In contrast, the fracture stress was found throughout to have a relatively constant strain-rate dependence of intermediate value between those obtained for the yield stress. These features confirmed that failure can be considered as competition between yield and fracture processes. The fracture stress became lower than the yield stress at both high and low strain rates where brittle fracture was observed, with fully ductile behaviour resulting in intermediate conditions where the fracture stress exceeded the yield stress. The pressure, strain rate and temperature dependence of the yield stress was well described by two Eyring processes acting in parallel, both processes being pressure dependent.  相似文献   
138.
112 chronic pain patients (mean age 48.4 yrs) completed the MMPI upon entering either an anesthesiologic or a psychiatric treatment program. Pretreatment MMPI performance was found to be successful in predicting patient outcome an average of 20 mo following treatment, with the K (Test-Taking Attitude), Hypochondriasis, Hysteria, and Masculinity and Femininity scales accounting for most of the variance. The strength of this relationship varied as a function of the measure of outcome and type of treatment received. Substantial MMPI differences were found when Ss with only one part of their body in pain were compared with those with multiple pain complaints. Significant MMPI differences were also found in comparisons based on Ss' sex, type of pain (e.g., head vs back), and type of treatment for which was referred (i.e., psychiatric vs anesthesiologic). Clinical implications of the observed MMPI differences are discussed. Results are seen as demonstrating the value of the MMPI as a clinical and research instrument within this population. (14 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
139.
In this paper the authors describe and analyse results that they obtained by infection of the guinea pig organism carried out by subcutaneous or intratracheal application with five mycobacterial strains, namely Myco bovis BCG-Praha, Myco the H37Ra, Myco Kansasii, Myco fortuitum and Myco smegmatis. At predetermined time intervals following subcutaneously or intratracheally performed infection (on 7th, 16th, 28th and 56th day after infection) transplantation of a Deals' guinea pig sarcoma cell suspension was carried out in guinea pigs by the intraltracheal route. As it appears from the results gained the applied mycobacteria exhibit a partial inhibition of growth od Deals' guinea pig sarcoma cells of different character. From among the utilized strains the Myco bovis BCP-Praha and the Myco tbc H37Ra exhibited the highest, Myco fortuitum and Myco smegmatis the lowest inhibitory activity. Intratracheally performed infections yielded in general better results on the growth inhibition than infections carried out with the same strain but by the subcutaneous route. Furthermore, in the experiments reported on in the present paper the authors could verify their earlier experience, namely that inhibition of growth of sarcoma cells is most pronounced at the time of maximal biological activity (logarithmic phase of multiplication) of the applied mycobacterium.  相似文献   
140.
The influence of tyre inflation pressure on whole-body vibrations transmitted to the operator during the movement of a cut-to-length timber harvester was evaluated. Vibration measurements were taken in three orthogonal (x, y, z) axes at tyre pressure settings of 138, 345 and 414 kPa. Vibration was predominant in the vertical (z) direction with the peak rms acceleration value for the operator seat (0.281 ms(-2)) occurring at approximately 3.2 Hz.The corresponding peak value for the operator cabin chassis was 0.425 m s(-2) at 4 Hz.At 414 kPa, there was potential health risk on the operator for exposures above 8h duration. The vibration total values recorded for the operator seat at the maximum tyre inflation pressure setting were classed as "fairly uncomfortable" (ISO standard 2631-1), and vertical seat vibration transmissibility was highest between 4 and 8 Hz at the 345 kPa tyre pressure setting. The recorded values of WBV were significantly reduced by a reduction in tyre inflation pressure which may therefore be used to moderate the magnitude of WBV on wheeled timber harvesters.  相似文献   
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