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941.
Hydroxyapatite coating on porous silicon substrate obtained by precipitation process 总被引:2,自引:0,他引:2
Chen Shaoqiang Zhu Ziqiang Zhu Jianzhong Zhang Jian Shi Yanling Yu Ke Wang Weiming Wang Xiaohua Feng Xiao Luo Laiqiang Shao Li 《Applied Surface Science》2004,230(1-4):418-424
Hydroxyapatite Ca10(PO4)6(OH)2 (HAP) is known as a bioactive and biocompatible material, HAP coatings were used to improve the biocompatible of substrate by many researcher, In this work, HAP thin films on porous silicon (PS) substrates have been prepared by aqueous precipitation method with rapid thermal annealing (RTA) processes. The HAP films had been prepared under the annealing temperature ranging from 300 to 1000 °C. By the measurement of X-ray diffraction (XRD), it was found that for the crystallinity optimization, the heat-treatment at 850–950 °C for 1 h would be favorable. Atomic force microscopy (AFM) and scanning electron microscope (SEM) measurements reveal a dense and smooth surface of the HAP film, and tightly adherence of the coating on porous silicon substrate after sintered. Thus, by this method, porous silicon could be increased its bioactivity and so that could be used in the biomedical area. 相似文献
942.
943.
Quenching of fluorescence from Na(32
P) and K(42
P) atoms by various collision partners was studied at 973 and 1273K. Excited alkali atoms were produced photolytically by excimer
laser light at 193nm. For each collision pair, the appropriate relative velocity was computed and used to evaluate the quenching
cross-section from the measured rate constants. Cross sections for CO2, O2 and N2 are large (10–60Å2) while for Ar, the values are <1 Å2. The results are compared with those of previous investigations as a function of relative velocity. Finally, implications
for combustion diagnostics are briefly discussed.
Received: 29 March 1996 相似文献
944.
945.
We propose a new method for computing multimode wave interactions in towing systems; our method is based on wave splitting
of the equations of a model in such a way that each computational step requires computation for only one mode. The efficiency
of the method is demonstrated by analysis of a concrete towing system with a turning towboat.
Translated fromDinamicheskic Sistermy. Vol. 12, pp. 55–64, 1993. 相似文献
946.
We perform the renewal of a Poisson field at a point on the basis of its values generated by a monotonically increasing curve.
We obtain the best mean-square estimate and its error.
Translated from Ukrainskii Matematicheskii Zhurnal, Vol. 50, No. 9, pp. 1272–1277, September, 1998. 相似文献
947.
We prove theorems that characterize the classes of functions whose best approximations by algebraic polynomials tend to zero
with given order. We construct approximations of solutions of operator-differential equations by polynomials in the inverse
operator.
Translated from Ukrainskii Matematicheskii Zhurnal, Vol. 50, No. 11, pp. 1506–1516, November, 1998. 相似文献
948.
We obtain an exact solution of the problem of the stress-strain state of an elastic piezoelectric half-space acted on by a
rigid elliptic die with a flat base. The axis of symmetry of the body coincides with the direction of the field of preliminary
polarization of the body. The solution is confined to the case of translational displacement of the die. We determine the
quantities that characterize the mechanical and electric fields that arise in the region of contact of the die with the half-space.
Bibliography: 7 titles.
Translated fromTeoreticheskaya i Prikladnaya Mekhanika, No. 28, 1998, pp. 40–52. 相似文献
949.
Zólomy A. Berceli T. Járó G. Hilt A. Marozsák T. 《Optical and Quantum Electronics》1998,30(11-12):969-983
Optical and Quantum Electronics - A new approach for the design and construction of low noise broadband optical receivers is presented utilizing distributed amplification based on hybrid integrated... 相似文献
950.
A. T. Barabanov 《Journal of Mathematical Sciences》1998,90(6):2537-2540
We propose criteria for controllability and observability of stationary systems specified by complex domain models. Conclusions
concerning controllability and observability are made on the basis of coefficients in the corresponding transfer functions.
Translated fromDinamicheskie Sistemy, Vol. 12, pp. 120–126, 1993. 相似文献