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991.
Barry  R.A. 《Electronics letters》1993,29(14):1252-1254
All-optical networks without switches are considered where the signals are routed based on wavelength only. 2 square root (M log/sub 2/( square root (2)M)) wavelengths are shown to be sufficient to build an M*M nonblocking connector without switches and without wavelength changers.<>  相似文献   
992.
993.
The performance of batch and continuous fluidized solids dryers has been modeled, with allowance for diffusional moisture transport in the dense phase particles and for interstitial gas-to-particle mass transfer within the dense phase, as well as for interphase exchange resistance between gas bubbles and the dense phase. Two types of boundary conditions are employed. Variations of the bed temperature and product moisture content in the bed with time are predicted numerically under various batch drying conditions. Exit product moisture contents, bed temperatures and outlet air humidities are also predicted for continuous drying at various mean residence times. The model can be used for homogeneous as well as bubbling fluidized bed drying. It can be used for a wide range of materials, including cereal grains and granular synthetic polymeric materials.  相似文献   
994.
Tests of biocompatibility are obligatory in the development of implants. Use of a polycarbonate transparent rabbit ear is a practical and relatively economical way of observing and documenting progressive interaction between potential prosthetic materials and granulation tissue. Fabrication of the chambers is technically straightforward and the surgical procedure involved in their insertion is simple and minimally invasive.  相似文献   
995.
996.
997.
998.
Oxygen nonstoichiometry in the distorted perovskite BaBiO3 has been studied by thermogravimetric analysis using controlled oxygen pressures. Three distinct regions of nonstoichiometry are observed with composition ranges which narrow as the temperature is lowered. Samples isolated from each region were shown by powder X-ray diffraction to retain the perovskite subcell but show different types of framework distortion. Low temperature reoxidation of the oxygen deficient phases is also described.  相似文献   
999.
1000.
Product constituent losses in ultra high temperature processing were examined with Arrhenius kinetics. An iteration procedure was utilized to develop time-temperature relationships for tubular heating systems. After introduction of the time-temperature relationship into the Arrhenius equation integration was performed to yield relationships representing product constituent losses. Time-temperature conditions for a direct system required to achieve the same losses were determined. A unique condition developed where direct and indirect systems may be designed having equivalent losses, independent of activation energies. An example is demonstrated utilizing whole milk heated by commercially available direct and indirect systems. Losses in five constituents were investigated for fifteen different indirect heating conditions. The mathematical uniqueness of the equivalence is examined.  相似文献   
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