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961.
Oscillation on the current-voltage curve measured by atomic force microscopy is observed when the distance between the tip and sample is large enough and beyond a critical value. The appearance of the oscillation is attributed to the excitation of electron standing waves between the tip and sample. From the first peak position and the voltage difference between the first two peaks on the current-voltage curve, the value of the work function at the detected point on silver film surface and the distance between the tip and the detected point can be calculated. 相似文献
962.
Potential-time decay curves were used to investigate the passivation of iron in dilute nitric acid solutions of different
concentrations. The effect of sulfate ions on the decay curves was also examined. It was observed that the decay curves formed
an almost flat potential segment ending after reaching the Flade potential (the potential at the end of the plateau). The
duration of the plateau was a function of both the initial holding potential and the acid concentration. The addition of sulfate
ions affected the decay duration without interfering with the Flade potential. This is worth noting in view of the well-known
dependence of the open-circuit potential decay on both pH and on the constituents of the solution.
Received: 26 February 1997 / Accepted: 14 May 1997 相似文献
963.
Yasuhiro Matsuda Yuji Miyazaki Shinji Sugihara Sadahito Aoshima Kazuya Saito Takahiro Sato 《Journal of Polymer Science.Polymer Physics》2005,43(20):2937-2949
Cloud‐point and binodal curves of the LCST type were obtained for aqueous solutions of a thermoresponsive polymer, poly [2‐(2‐ethoxy)ethoxyethyl vinyl ether], poly(EOEOVE). The cloud‐point curve obtained was very flat except in a dilute region, that is the cloud‐point temperature was insensitive to the polymer concentration, resembling the cloud‐point curve for aqueous solutions of poly(N‐isopropylacrylamide). On the other hand, the binodal curve obtained was parabolic, and located within the two‐phase region of the cloud‐point curve. Accompanied with the phase separation, a sharp endothermic peak was observed in a region including the cloud‐point and binodal temperatures. The reciprocal of the osmotic compressibility ?Π/?c obtained by sedimentation equilibrium indicated that water changes from a good to poor solvent for poly(EOEOVE) with increasing temperature. Analyzing the ?Π/?c data by a thermodynamic perturbation theory, we determined the interchain interaction parameters, the hard‐core diameter d and the depth ε of the square‐well potential. Theoretical binodal and endothermic curves calculated by the perturbation theory using the estimated interaction parameters reproduced experimental ones semiquantitatively, but the theoretical binodal disagreed with the experimental flat cloud‐point curve. The disagreement at high concentrations was in the opposite direction to that expected from the sample polydispersity in the molecular weight. © 2005 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys 43: 2937–2949, 2005 相似文献
964.
965.
966.
For it is proven that a (q+1)-set in PG(2,q) having more than nuclei on an irreducible, non-singular cubic curve has to be a line.
Received 30 October 2001. 相似文献
967.
968.
本文在Landes规则化方法基础上提出单试件确定塑性因子法,即只使用单个试件的实验记录P,V和a就可求得材料塑性因子ηpl.其中实时裂纹长度a可以卸载柔度法或物理测量得到.通常规则化方法需一组试件.单试件法可避免多试件存在的尺寸分散性,也可使实验过程简化.文中结合304不锈钢实验进行分析,结果表明单试件法简便、实用、精度较高. 相似文献
969.
Ling Long 《Journal of Number Theory》2004,109(2):299-318
We develop an algorithm to determine a one-parameter family of elliptic curves associated to a one-parameter family of K3 surfaces with generic Picard number 19 by a Shioda-Inose structure. The family of elliptic curves is determined up to an isomorphism and an isogeny. An application to a generalized congruence number problem is also discussed. 相似文献
970.
Geir Ellingsrud Stein Arild Strø mme 《Journal of the American Mathematical Society》1996,9(1):175-193
We outline a strategy for computing intersection numbers on
smooth varieties with torus actions using a residue formula of Bott. As an example, Gromov-Witten numbers of twisted cubic and elliptic quartic curves on some general complete intersection in projective space are computed. The results are consistent with predictions made from mirror symmetry computations. We also compute degrees of some loci in the linear system of plane curves of degrees less than 10, like those corresponding to sums of powers of linear forms, and curves carrying inscribed polygons.
smooth varieties with torus actions using a residue formula of Bott. As an example, Gromov-Witten numbers of twisted cubic and elliptic quartic curves on some general complete intersection in projective space are computed. The results are consistent with predictions made from mirror symmetry computations. We also compute degrees of some loci in the linear system of plane curves of degrees less than 10, like those corresponding to sums of powers of linear forms, and curves carrying inscribed polygons.