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191.
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WYETH Paul 《中国科学B辑(英文版)》2011,(6)
Silks are among the most precious ancient and historic artefacts worldwide. While washing removes the natural gum from the fibres during the fabrication of most silk textiles, for a small proportion of historic silks some or perhaps all of the sericin still remains. This paper investigated the effect of sericin coating on the aging of silk fibroin by means of ATR and tensile testing. The results show that sericin can provide some extent of protection from light and heat aging. However, in high humidity envi... 相似文献
194.
We consider the critical focusing wave equation $(-\partial _t^2+\Delta )u+u^5=0$ in ${\mathbb{R }}^{1+3}$ and prove the existence of energy class solutions which are of the form $$\begin{aligned} u(t,x)=t^\frac{\mu }{2}W(t^\mu x)+\eta (t,x) \end{aligned}$$ in the forward lightcone $\{(t,x)\in {\mathbb{R }}\times {\mathbb{R }}^3: |x|\le t, t\gg 1\}$ where $W(x)=(1+\frac{1}{3} |x|^2)^{-\frac{1}{2}}$ is the ground state soliton, $\mu $ is an arbitrary prescribed real number (positive or negative) with $|\mu |\ll 1$ , and the error $\eta $ satisfies $$\begin{aligned} \Vert \partial _t \eta (t,\cdot )\Vert _{L^2(B_t)} +\Vert \nabla \eta (t,\cdot )\Vert _{L^2(B_t)}\ll 1,\quad B_t:=\{x\in {\mathbb{R }}^3: |x|<t\} \end{aligned}$$ for all $t\gg 1$ . Furthermore, the kinetic energy of $u$ outside the cone is small. Consequently, depending on the sign of $\mu $ , we obtain two new types of solutions which either concentrate as $t\rightarrow \infty $ (with a continuum of rates) or stay bounded but do not scatter. In particular, these solutions contradict a strong version of the soliton resolution conjecture. 相似文献
195.
Zaliya A. Sabirova Marianna M. Danilova Nikolai A. Kuzin Valerii A. Kirillov Vladimir I. Zaikovskii Tamara A. Krieger 《Reaction Kinetics and Catalysis Letters》2009,97(2):363-370
XRD, mercury porosimetry, low-temperature nitrogen adsorption and electron microscopy were used to study peculiarities of
the formation of reinforced composite nickel catalysts. The catalysts were prepared by sintering powdered metallic nickel
with a supported nickel catalyst (GIAP-3 or NIAP-18) applied to a reinforcing stainless steel gauze. It was found that a metal
matrix, in the pores of which supported catalyst particles were distributed, was formed in the composite catalysts. The NIAP-18-based
catalyst exceeded the GIAP-3-based catalyst in activity toward the methane steam reforming. The NIAP-18-based catalyst was
as active as the Cr2O3-doped NIAP-18-based catalyst, but showed a worse coke-resistance. A chromium oxide additive increased the activity of the
GIAP-3-based catalyst. 相似文献
196.
Wolfgang Krieger 《Probability Theory and Related Fields》1969,11(2):98-119
Summary This paper continues the investigations of On Non-Singular Transformations of a Measure Space I. 相似文献
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199.
R. Steiner H.-G. Boyen M. Krieger A. Plettl P. Widmayer P. Ziemann F. Banhart R. Kilper P. Oelhafen 《Applied Physics A: Materials Science & Processing》2003,76(1):5-13
[Fe/B]n ≥2 multilayers were prepared by thermal evaporation, ion-beam sputtering and laser ablation. By applying in situ electron spectroscopies
(UPS, XPS) and monitoring the electrical resistance during layer growth, evidence could be provided for the occurrence of
interface reactions within the range of studied deposition temperatures (77 K ≤T ≤300 K). These reactions result in amorphous
FexB100-x phases, which are spatially restricted to a width of less than 3 nm at the original interface. The amorphicity of the reacted
interlayers was unequivocally proven by additional high-resolution electron microscopy (HRTEM) and their characteristically
changed magnetic properties. Due to the well-defined width of the interface reaction, homogeneous amorphous FexB100-x films can be obtained by reducing the individual Fe and B layer thicknesses to below the above reaction depth, while for
larger thicknesses layer sequences of the crystalline/amorphous/crystalline type will result.
Received: 30 January 2002 / Accepted: 31 January 2002 / Published online: 10 September 2002
RID="*"
ID="*"Corresponding author. Fax: +49-731/502-2963, E-mail: hans-gerd.boyen@physik.uni-ulm.de 相似文献
200.