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91.
92.
A series of quench tests on hollow cylindrical specimens made of the machinable ceramic, Pyrophyllite, has been performed. The specimens consistently fractured with two diametrically opposite longitudinal cracks. Finite element analysis indicates that the primary crack occurred at the stage when the strain energy of the cylinder reached its maximum during the thermal transient process, while the secondary crack was caused by stress waves generated following the primary crack. This is supported by experimental observation of the time of fracture and the crack morphology. The work reported here helps to shed light on the fracture criterion for brittle cylindrical components under transient thermal and dynamic loadings.  相似文献   
93.
94.
This is a study on the loss-grief reaction and coping behavior of a mother whose child died of brain tumor. The researcher used field methods to collect data and analyze observations of mother-nurse interaction. The results showed that this mother had self-blame depression, and guilt feelings and affected the whole family. With the help of nurses and various supportive resources the mother was finally able to go through the grieving process smoothly.  相似文献   
95.
Decyl isonicotiniate and decyl nicotiniate permit a rapid extraction of palladium(II) from its hydrochloride solutions. Decyl picoliniate is not a suitable extractant. 4-Octylphenylamine can act as a phase transfer catalyst when its concentration in the organic phase is at least 2·5 × 10?4 M . It seems that the interfacial adsorption of pyridine carboxylates and of 4-octylphenylamine is not the decisive phenomenon in palladium(II) extraction. The negligible protonation of the pyridine-type extractants and the phase transfer catalysis explains well the quick extraction of palladium(II) with the commercial and highly hydrophobic extractant ACORGA CLX-50.  相似文献   
96.
The effect of addition of 3 g/L of commercially available transglutaminase preparation to protein extracts obtained from mechanically recovered poultry meat was studied. The content of free thiol groups (–SH), thermal drip and gel texture were determined. After pre-incubation at 7–8 °C for 1, 3, 5 and 24 h, the samples were subjected to one-step heating at 50, 60, 70 and 80 °C and two-step heating at 50/80, 55/80 and 60/80 °C. The addition of preparation and the extension of pre-incubation time led to decrease of free -SH groups content. After heating, the number of thiol groups decreased, the texture was improved, but thermal drip from gels increased. The amount of –SH groups in gel extracts subjected to one-step heating decreased with simultaneous increase of mechanical strength of gels. Protein gels subjected to two-step heating exhibited higher firmness than gels subjected to one-step heating. Thus, the 3 g/L addition of transglutaminase preparation in combination with one-step thermal processing at 70 °C and pre-incubation for 3 h contributed to improvement of texture properties of model gels and low thermal drip.  相似文献   
97.
Discusses the Dutch health system, focusing on the increasing number of clinical psychologists who are offering their services to the public as private practitioners. This move toward primary health care given by the "first-line psychologist" results from a generalistic frame of reference in which a wide range of psychic, psychosocial, and psychosomatic difficulties are treated with a time-limited framework. In this way, the clinical psychologist contributes to changing the habits and lifestyles of a broad population. Responses to the system are encouraging, and the government has begun to respond positively to the system. (5 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
98.
We describe RTblob, a high speed vision system that detects objects in cluttered scenes based on their color and shape at a speed of over 800 frames/s. Because the system is available as open-source software and relies only on off-the-shelf PC hardware components, it can provide the basis for multiple application scenarios. As an illustrative example, we show how RTblob can be used in a robotic table tennis scenario to estimate ball trajectories through 3D space simultaneously from four cameras images at a speed of 200 Hz.  相似文献   
99.
100.
Crease surfaces describe extremal structures of 3D scalar fields. We present a new region-growing-based approach to the meshless extraction of adaptive nonmanifold valley and ridge surfaces that overcomes limitations of previous approaches by decoupling point seeding and triangulation of the surface. Our method is capable of extracting valley surface skeletons as connected minimum structures. As our algorithm is inherently mesh-free and curvature adaptive, it is suitable for surface construction in fields with an arbitrary neighborhood structure. As an application for insightful visualization with valley surfaces, we choose a low frequency acoustics simulation. We use our valley surface construction approach to visualize the resulting complex-valued scalar pressure field for arbitrary frequencies to identify regions of sound cancellation. This provides an expressive visualization of the topology of wave node and antinode structures in simulated acoustics.  相似文献   
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