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41.
42.
The correlation between neutron-to-proton yield ratio (Rnp) and neutron skin thickness (δnp) in neutron-rich projectile induced reactions is investigated within the framework of the Isospin-Dependent Quantum Molecular Dynamics (IQMD) model. The density distribution of the Droplet model is embedded in the initialization of the neutron and proton densities in the present IQMD model. By adjusting the diffuseness parameter of neutron density in the Droplet model for the projectile, the relationship between the neutron skin thickness and the corresponding Rnp is obtained. The results show strong linear correlation between Rnp and δnp for neutron-rich Ca and Ni isotopes. It is suggested that Rnp may be used as an experimental observable to extract δnp for neutron-rich nuclei, which is very interesting in the study of the nuclear structure of exotic nuclei, the equation of state (EOS) of asymmetric nuclear matter and neutron-rich matter in astrophysics, etc. 相似文献
43.
Bogdan Kaźmierczak Kazimierz Piechór 《Mathematical Methods in the Applied Sciences》2011,34(3):325-337
We study traveling wave solutions to a system of four non‐linear partial differential equations, which arise in a tissue interaction model for skin morphogenesis. Under the assumption that the strength of attachment of the epidermis to the basal lamina is sufficiently large, we prove the existence and uniqueness (up to a translation) of traveling wave solutions connecting two stationary states of the system with the dermis and epidermis cell densities being positive. We discuss the problem of the minimal wave speed. Copyright © 2010 John Wiley & Sons, Ltd. 相似文献
44.
Yanhui Chen Ganji Zhong Benjamin S. Hsiao Zhongming Li 《Journal of Polymer Science.Polymer Physics》2013,51(22):1618-1631
The structure evolution of the oriented layer (skin) and unoriented layer (core) from injection‐molded isotactic polypropylene samples upon uniaxial drawing is probed by in situ synchrotron X‐ray scattering. The X‐ray data analysis approach, called “halo method”, is used to semiquantitatively identify the transformation process of crystal phase upon uniaxial drawing. The results verify the validation of the stress‐induced crystal fragmentation and recrystallization process in the deformation of the injection‐molded samples under different temperatures. Furthermore, the end of strain softening region in the engineering stress‐strain curves explicitly corresponds to the transition point from the stress‐induced crystal fragmentation to recrystallization process. Basically, the skin and core layers of the injection‐molded parts share the similar deformation mechanism as aforementioned. The stretching temperature which dramatically affects the relative strength between the entanglement‐induced tie chains and the adjacent crystalline lamellae determines the crystal structural evolution upon drawing. © 2013 Wiley Periodicals, Inc. J. Polym. Sci., Part B: Polym. Phys. 2013, 51, 1618–1631 相似文献
45.
Two components of conductor topography can impact conductor loss for signals in the GHz frequency range: conductor–ceramic interface roughness and conductor edge angle. This study is an experimental investigation of the influence of these conductor topographies on conductor loss in microstrip circuits produced by thick‐film technology. The aluminum nitride ceramic substrates have different surface roughnesses due to different surface finish processes. The substrate surfaces were characterized using conventional and length‐scale fractal analysis. The conductor–ceramic interface was measured with a contact profilometer. The conductor edge angle and conductor edge profile were measured optically. It was found that there is a direct correlation between conductor loss and conductor edge angle, whereas there is an inverse correlation between loss and substrate roughness or relative length of the conductor–ceramic interface. This is the opposite result to the conventional expectation of surface roughness effects on conductor loss. There is also a negative correlation between conductor edge angle and surface roughness or relative length. The loss behavior can be explained by the interaction of the conductor paste with the surfaces during processing. The paste tends to spread more on the smoother surfaces, and thus creates an elongated edge of diminishing cross‐section and a small edge angle. This leads to greater conductor loss. Copyright © 2009 John Wiley & Sons, Ltd. 相似文献
46.
回顾国内外小腿前外侧岛状皮瓣的研究成果,总结了小腿前外侧岛状皮瓣的应用解剖学基础和临床应用,讨论了目前报道的小腿前外侧岛状皮瓣修复小腿下段皮肤缺损的优缺点,并对优化该皮瓣在临床上的应用提出了展望. 相似文献
47.
DSC measurements on full thickness mice skin 总被引:1,自引:0,他引:1
Highly lipophilic basic drugs, the antiestrogens AE1 and AE2 shall be delivered transdermally. DSC as an additional tool in
combination with classic investigation techniques should be used to clarify permeation enhancement. Skin treatment with pure
solvents, polyethyleneglycol (PG) and dimethylisosorbide (DMI), slightly changed the phase transition temperatures. Formulations
containing lauric acid markedly shifted these transitions to lower temperatures, indicating a lipid-fluidising action of lauric
acid. In those cases an additional endothermic peak was observed around 40°C, which is attributed to the melting of crystalline
lauric acid. Since the DSC program started at -20°C, it is very likely that lauric acid in the skin samples crystallized.
A formulation of polyethyleneglycol and lauric acid leads to significantly higher deposition of lauric acid into the skin,
in opposition to dimethylisosorbide/lauric acid formulation. These findings correspond to the results from our in-vitro permeation
studies, where a significantly higher transdermal steady-state flux of lauric acid from polyethyleneglycol-formulation in
comparison to dimethylisosorbide-formulation was observed. By this unique combination of polyethyleneglycol and lauric acid,
the barrier is obviously modified in a way, which allows the highly lipophilic antiestrogens to permeate easily through the
skin. So, from this formulation steady-state fluxes of AE-1 were observed, representing approximately the same value compared
to the unhindered permeation through skin without stratum corneum. The grade of temperature shift on the skin lipids to lower
temperatures can be correlated with softening effects and the enhancement potential of the formulation.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
48.
Stefano Longhi 《Annalen der Physik》2023,535(11):2300291
Strongly-correlated systems in non-Hermitian models are an emergent area of research. Herein, a non-Hermitian Hubbard model is considered, where the single-particle hopping amplitudes on the lattice are not reciprocal, and provide exact analytical results of the spectral structure in the two-particle sector of Hilbert space under different boundary conditions. The analysis unveils some interesting spectral and dynamical effects of purely non-Hermitian nature and that deviate from the usual scenario found in the single-particle regime. Specifically, a spectral phase transition of the Mott-Hubbard band on the infinite lattice is predicted as the interaction energy is increased above a critical value, from an open to a closed loop in complex energy plane, and the dynamical dissociation of doublons, i.e., instability of two-particle bound states, in the bulk of the lattice, with a sudden revival of the doublon state when the two particles reach the lattice edge. Particle dissociation observed in the bulk of the lattice is a clear manifestation of non-Hermitian dynamics arising from the different lifetimes of single-particle and two-particle states, whereas the sudden revival of the doublon state at the boundaries is a striking burst edge dynamical effect peculiar to non-Hermitian systems with boundary-dependent energy spectra, here predicted for the first time for correlated particles. 相似文献
49.
Neutron skin thickness of 90Zr and symmetry energy constrained by charge exchange spin-dipole excitations
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The charge exchange spin-dipole (SD) excitations of \begin{document}$ ^{90} $\end{document} ![]()
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Zr are studied using the Skyrme Hartee-Fock plus proton-neutron random phase approximation with SAMi-J interactions. The experimental value of the model-independent sum rule obtained from the SD strength distributions of \begin{document}$ ^{90} $\end{document} ![]()
![]()
Zr(p, n)\begin{document}$ ^{90} $\end{document} ![]()
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Nb and \begin{document}$ ^{90} $\end{document} ![]()
![]()
Zr(n, p)\begin{document}$ ^{90} $\end{document} ![]()
![]()
Y is used to deduce the neutron skin thickness. The neutron skin thickness \begin{document}$ \Delta r_{np} $\end{document} ![]()
![]()
of \begin{document}$ ^{90} $\end{document} ![]()
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Zr is extracted as \begin{document}$ 0.083\pm0.032 $\end{document} ![]()
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fm, which is similar to the results of other studies. Based on the correlation analysis of the neutron skin thickness \begin{document}$ \Delta r_{np} $\end{document} ![]()
![]()
and the nuclear symmetry energy J as well as its slope parameter L, a constraint from the extracted \begin{document}$ \Delta r_{np} $\end{document} ![]()
![]()
leads to the limitation of J to \begin{document}$ 29.2 \pm 2.6 $\end{document} ![]()
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MeV and L to \begin{document}$ 53.3 \pm 28.2 $\end{document} ![]()
![]()
MeV. 相似文献
50.
Aparna L. Joshi Pratiksha H. Roham Rooth Mhaske Mahadev Jadhav Kavitha Krishnadas Amol Kharat 《Natural product research》2015,29(23):2261-2264
Calotropis procera (family: Asclepiadaceae) contains cardiac glycosides which are cytotoxic to cancer cells. The extracts of C. procera have been reported to be cytotoxic to many cancer cell lines and this is the first report against the human skin melanoma cells (SK-MEL-2). The SK-MEL-2 cells treated with C. procera methanolic extract (CPME) were analysed for growth inhibition and apoptosis. The exposure of phosphatidylserine in apoptotic SK-MEL-2 was analysed by using the Annexin-V FITC flow cytometry method. In CPME-treated SK-MEL-2 cells, 19.6% of apoptotic and 58.3% dead cells were observed. The 15.97% and 15.85% of early apoptotic cells were found at 20 μg/mL of the ouabain and paclitaxel, respectively. Active caspases, nuclear degradation confirmed apoptotic SK-MEL-2 cells in time- and dose-dependent manner. The cell cycle analysis shows that CPME treated cells halt at G2/M phase. Significant cytotoxic activity of CPME against SK-MEL-2 may be attributed to its high cardenolide content. 相似文献