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991.
992.
Ju H. Choi Alfred Margaryan Ashot Margaryan Frank G. Shi 《Journal of Materials Science》2008,43(3):1109-1113
The dependence of thermo-mechanical, and mechanical properties on various rare earth dopants (RE) including Nd2O3, Er2O3, and Yb2O3 in 0.4MgF2-0.4BaF2-0.1Ba(PO3)2-0.1Al(PO3)3 glasses (MBBA system) is systematically investigated. MBBA system doped with RE dopants presented the potential application
in the field of communication and high power layer system in the previous reports. In this work, it is found that the density
of the doped glass increases with an increasing of RE concentration, which could be understood in terms of cationic field
strength (CFS) effect. The Knoop hardness is found to decrease with the loading time and dopant concentration due to the indentation
size effect (ISE) effect. The observed decrease of thermal expansion coefficient and the increase of glass transition temperature
T
g with increasing dopant concentration are elucidated in terms of the increasing number of strong covalent bonds with increasing
RE dopant concentration. Those results will be of paramount importance before designing optical devices. 相似文献
993.
Frank R. Cichocki Gavin Chen Jack Zhou Meng Deng 《Materials science & engineering. C, Materials for biological applications》2008,28(3):331-335
Bioabsorbable polyglycolide-co-lactide microtubes have been developed for the continuous delivery of fluid medications directly to an operative site. Studies conducted with radio-opaque solution using porcine models indicated that infusion of fluids in the wound site was rapid and complete. The tissue reaction to the microtube was generally characterized as minimal to mild with complete absorption occurring within 56 days postimplantation. Processing–microstructure-property relationships and bio-degradation characteristics of the microtubes are presented. 相似文献
994.
Database views are traditionally described as unmaterialized queries, which may be coincidentally updatable according to some fixed criteria. One of the problems in updating through views lies in determining whether a given view modification can be correctly translated by the system. To define an updatable view, a view designer must be aware of how an update request in the view will be mapped into updates of the underlying relations. Furthermore, because of side effects, the view designer must also be made aware of the effects of isolated updates back into the view. To address this problem, we present a general algorithm that predicts the effects of arbitrary mapping policies. Given an update policy, this algorithm indicates whether a desired update will, in fact, occur in the view and describes all possible side effects it may have, documenting the conditions under which they occur. The algorithm subsumes the results obtained by other view design tools, and generalizes their use to encompass a larger class of views. 相似文献
995.
Frank D. Conforti Jocelyn A. Totty 《International Journal of Food Science & Technology》2007,42(9):1101-1106
The shelf life quality of freshly harvested Golden Delicious apples coated with three individually developed lipid/hydrocolloid coatings was assessed throughout refrigerated storage. The apples were monitored for 8 weeks. The coatings resulted in low internal O2 and the least loss of fruit firmness when compared with the non‐coated apple group. The coated apples had very little starch breakdown, minimum flesh colour development, or loss of titratable acidity content. Soluble solids and fresh weight loss remained unchanged for both the non‐coated and coated groups. Sensory analysis confirmed that the coated apples maintained consistent quality in firmness, crispness and juiciness throughout the storage period. 相似文献
996.
997.
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999.
Anouk de Brauwere Fjo De Ridder Rik Pintelon Jeroen Meersmans Johan Schoukens Frank Dehairs 《Computers & Geosciences》2008,34(12):1781-1790
The past environment is often reconstructed by measuring a certain proxy (e.g. δ18O) in an environmental archive, i.e. a species that gradually accumulates mass and records the current environment during this mass formation (e.g. corals, shells, trees, etc.). When such an environmental proxy is measured, its values are known on a distance grid. However, to relate the data to environmental variations, the date associated with each measurement has to be known too. This transformation from distance to time is not straightforward to solve, since species usually do not grow at constant or known rates. In this paper, we investigate this problem for environmental archives exhibiting a certain periodicity. In practice, the method will be applicable to most annually resolved archives because these contain a seasonal component, e.g. clams, corals, sediment cores or trees. Due to variations in accretion rate the data along the distance axis have a disturbed periodic profile. In this paper, a method is developed to extract information about the accretion rate, such that the original (periodic, but further unknown) signal as a function of time can be recovered. The final methodology is quasi-independent of choices made by the investigator and is designed to deliver the most precise and accurate result. Every step in the procedure is described in detail, the results are tested on a Monte-Carlo simulation, and finally the method is exemplified on a real world example. 相似文献
1000.