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21.
A.D. Linde 《Nuclear Physics B》1983,216(2):421-445
In this paper we study kinetics of the first-order phase transitions in gauge theories with spontaneous symmetry breaking. A general theory of the decay of the metastable phase (false vacuum) at a finite temperature is developed. A number of concrete examples are considered, which will make it possible to study kinetics of phase transitions in a wide class of theories without complicated computer calculations. 相似文献
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23.
Temperature dependence of coupling constants and the phase transition in the Coleman-Weinberg theory
A.D. Linde 《Physics letters. [Part B]》1982,116(5):340-342
It is shown that the temperature dependence of the effective Higgs boson coupling constants leads to a considerable modification of the theory of the SU(5) Coleman-Weinberg phase transition. 相似文献
24.
van de Grampel RD Ming W Gildenpfennig A van Gennip WJ Laven J Niemantsverdriet JW Brongersma HH de With G van der Linde R 《Langmuir : the ACS journal of surfaces and colloids》2004,20(15):6344-6351
In this paper, we investigate the surface properties of a series of copolymers of perfluoroalkyl methacrylate (CH2 = C(CH3)COOCH2CnF(2n + 1), n = 1, 6, or 10) and methyl methacrylate (MMA) and of blends of perfluorooctyl-end-capped poly(methyl methacrylate) (PMMA) and pure PMMA. The introduction of perfluoroalkyl groups significantly lowers the polymer surface energy as determined by the acid-base approach. X-ray photoelectron spectroscopy (XPS) confirms a higher fluorine concentration in the surface region (the outer 3.8 nm) as compared to in the bulk. The fluorine density in the outermost atomic layer is quantitatively determined by low-energy ion scattering (LEIS). A linear relationship is found between the fluorine density in the outermost atomic layer and the surface energy of the partially fluorinated polymethacrylates, irrespective of the length of the perfluoroalkyl chain. This linearity confirms Langmuir's "principle of independent surface action". Deviation from this linear relationship exists for both highly and sparsely fluorinated polymethacrylates and can be ascribed to the local (surface) ordering of the fluorinated tails and MMA units, respectively. This study may offer one further step toward a deeper understanding of the correlations between macroscopic surface properties and microscopic surface chemical composition. 相似文献
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26.
N. A. Inogamov Yu. V. Petrov S. I. Anisimov A. M. Oparin N. V. Shaposhnikov D. von der Linde J. Meyer-ter-Vehn 《JETP Letters》1999,69(4):310-316
Recent experiments have utilizied high-power subpicosecond laser pulses to effect the ultrafast heating of a condensed material
to temperatures far above the critical temperature. Using optical diagnostics it was established that a complicated density
profile with sharp gradients, differing substantially from an ordinary rarefaction wave, forms in the expanding heated matter.
The present letter is devoted to the analysis of the expansion of matter under the conditions of the experiments reported
by D. von der Linde, K. Sokolowski-Tinten, and J. Bialkowski, Appl. Surf. Science 109/110, 1 (1996); K. Sokolowski-Tinten, J. Bialkowski, A. Cavalleri et al., Proc. Soc. Photo-Opt. Instum. Eng. 3343, 46 (1998); and, K. Sokolowski-Tinten, J. Bialkowski, A. Cavalleri et al., Phys. Rev. Lett. 81, 224 (1998). It is shown that if the unloading adiabat passes through the two-phase region, a thin liquid shell filled with
low-density two-phase matter forms in the expanding material. The shell moves with a constant velocity. The velocity in the
two-phase material is a linear function of the coordinate (flow with uniform deformation), and the density is independent
of the coordinate and decreases with time as t
−1.
Pis’ma Zh. éksp. Teor. Fiz. 69, No. 4, 284–289 (25 February 1999) 相似文献
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28.
利用溶液聚合和成酰胺反应合成了多功能梳状两亲性共聚物,聚(甲基丙烯酸-co-甲基丙烯酸十八酯)-(乙醇胺-乙二胺叶酸)(PSM-EE-FA).用红外光谱(FTIR),核磁共振(1H-NMR)及凝胶渗透色谱(GPC)表征了该聚合物的结构及分子量分布.实验结果证明合成了该聚合物,其数均分子量(Mn)为28600,多分散性为1.375.用该两亲梳状聚合物包覆油溶性CdSe/ZnS量子点,通过相转移作用,得到水溶性靶向量子点(PSM-EE-FA-QDs).该水溶性量子点溶液具有较好的稳定性.通过紫外-可见(UV-Vis)及荧光发射光谱分析对该量子点的光学性质进行研究.结果表明,PSM-EE-FA-QDs的紫外-可见光谱及荧光发射光谱峰形与原量子点基本一致.由于量子点表面聚合物层的形成,峰位发生少量红移.该量子点水溶液的荧光强度是原量子点氯仿溶液的98%,荧光产率是原量子点氯仿溶液的95%.动态光散射(DLS)及透射电镜(TEM)测试结果表明水溶性量子点分布均匀.合成的水溶性量子点不但光学性能稳定,而且聚合物及水溶性量子点的合成方法较为简便. 相似文献
29.
Skrodzka E Łapa A Linde BB Rosenfeld E 《The Journal of the Acoustical Society of America》2011,130(4):2186-2194
Similarities and differences in vibrational behavior of two guitars having a symmetric Torres bracing pattern and an asymmetric pattern forming a lattice on a soundboard are investigated by means of the modal analysis technique and laser Doppler vibrometry (LDV) measurements. Instruments are investigated before and after a bridge and strings assembling (i.e., they are incomplete or complete). The bracing pattern and the absence/presence of the bridge and strings have some effect on modal frequencies and mode shapes. The bracing pattern does not affect the sequence of at least first three low frequency mode shapes of incomplete/complete instruments but affects their modal frequencies. Depending on frequency, the bridge behaves either as a rigid or a flexible structure. 相似文献