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21.
HA Mook DM Paul BC Sales LA Boatner L Cussen 《Canadian Metallurgical Quarterly》1988,38(16):12008-12010
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Y. Romanyshyn S. Guimond H. Kuhlenbeck S. Kaya R. P. Blum H. Niehus S. Shaikhutdinov V. Simic-Milosevic N. Nilius H.-J. Freund M. V. Ganduglia-Pirovano R. Fortrie J. Döbler J. Sauer 《Topics in Catalysis》2008,50(1-4):106-115
Oxidation catalysts are modeled by oxide single crystals, thin oxide films, as well as supported oxide nanoparticles. We characterize the surface of those materials using a variety of surface sensitive techniques including scanning tunneling microscopy and spectroscopy, photoelectron spectroscopy, infrared spectroscopy, and thermal desorption spectroscopy. We find temperature dependent structural transformations from V2O5(001) to V2O3(0001) via V6O13(001). V2O3(0001) is found to be vanadyl terminated in an oxygen ambient and it loses the vanadyl termination after electron bombardment. It is shown that the concentration of vanadyl groups controls the selectivity of the methanol oxy-dehydrogenation towards formaldehyde. A proposal for the mechanism is made. The results on single crystalline thin films are compared with similar measurements on deposited vanadia nanoparticles. The experimental results are correlated with theoretical calculations and models. 相似文献
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Raab W. Bruels N. Hachmann U. Harnisch J. Ramacher U. Sauer C. Techmer A. 《Design & Test of Computers, IEEE》2003,20(1):8-15
New generations of automobiles will include driver assistance systems requiring powerful, low-cost processors to handle video/camera applications and to enable fast, convenient application development. Shrinking feature sizes on processors already in development will bring substantial increases in system speed and functionality. 相似文献
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JK Kang SW Lee MW Baik BC Son YK Hong CK Jung KH Ryu 《Canadian Metallurgical Quarterly》1998,14(7):297-301
Accurate assessment and replacement of blood loss and fluid-electrolyte deficit during craniosynostosis repair is difficult owing to patient size and the diversity of surgical technique. Forty-three patients undergoing primary craniosynostosis repair over a 10-year period were studied retrospectively to determine blood loss and fluid deficit and to assess blood transfusion practices during both intraoperative and postoperative periods. Blood loss was calculated on the basis of estimated red cell mass (ERCM) and fluid-electrolyte imbalance was investigated with blood samplings. Blood transfusion was considered appropriate if the postoperative or posttransfusion ERCM was within 12% of the preoperative value. Estimated fluid requirement (EFR) was used in 4 ml kg(-1) h(-1) except for neonates. Intraoperatively, 80% of all patients were appropriately managed with respect to blood transfusion and EFR. Postoperatively only 20% of the patients receiving transfusions were transfused appropriately. In 23.3% of these patients (10/43) unexpected respiratory distress developed immediately after their recovery from the anesthesia. With the measurement of estimated blood volume and allowable blood loss, appropriate transfusion could be achieved for the successful treatment of the primary craniosynostosis. 相似文献
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M Patel RF Kaltenbach DA Nugiel RJ McHugh PK Jadhav LT Bacheler BC Cordova RM Klabe S Erickson-Viitanen S Garber C Reid SP Seitz 《Canadian Metallurgical Quarterly》1998,8(9):1077-1082
Cyclic urea SD146, a potent HIV protease inhibitor bearing a flat resistance profile, possessed poor solubility and bioavailability, which precluded further development of the compound. In an effort to improve upon the pharmacokinetic profile of the compound, several analogs modified at the P1/P1' residues were prepared and evaluated. Several of those compounds displayed significant improvement of physical properties. 相似文献
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