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101.
Macromolecule Loading into Spherical,Elliptical, Star‐Like and Cubic Calcium Carbonate Carriers 下载免费PDF全文
Dr. Bogdan V. Parakhonskiy Dr. Alexey M. Yashchenok Dr. Senem Donatan Dr. Dmitry V. Volodkin Dr. Francesco Tessarolo Prof. Renzo Antolini Prof. Helmuth Möhwald Prof. Andre G. Skirtach 《Chemphyschem》2014,15(13):2817-2822
We fabricated calcium carbonate particles with spherical, elliptical, star‐like and cubical morphologies by varying relative salt concentrations and adding ethylene glycol as a solvent to slow down the rate of particle formation. The loading capacity of particles of different isotropic (spherical and cubical) and anisotropic (elliptical and star‐like) geometries is investigated, and the surface area of such carriers is analysed. Potential applications of such drug delivery carriers are highlighted. 相似文献
102.
Birgit Fuchs Prof. Dr. Gunter Heymann Xuefei Wang Abudukadi Tudi Dr. Lkhamsuren Bayarjargal Dr. Renée Siegel Adrian Schmutzler Prof. Dr. Jürgen Senker Dr. Bastian Joachim-Mrosko Dr. Andreas Saxer Prof. Dr. Zhihua Yang Prof. Dr. Shilie Pan Prof. Dr. Hubert Huppertz 《Chemistry (Weinheim an der Bergstrasse, Germany)》2020,26(30):6851-6861
La3B6O13(OH) was obtained by a high-pressure/high-temperature experiment at 6 GPa and 1673 K. The compound crystallizes in the space group P21 (no. 4) with the lattice parameters a=4.785(2), b=12.880(4), c=7.433(3) Å, and β=90.36(10)°, and is built up of corner- as well as edge-sharing BO4 tetrahedra. It represents the first acentric high-pressure borate containing these B2O6 entities. The compound develops borate layers of „sechser“-rings with the La3+ cations positioned between the layers. Single-crystal and powder X-ray diffraction, vibrational and MAS NMR spectroscopy, second-harmonic generation (SHG) and thermoanalytical measurements, as well as computational methods were used to affirm the proposed structure and the B2O6 entities. 相似文献
103.
We show that a velocity field u satisfying the stationary Navier–Stokes equations on the entire plane must be constant under
the growth condition lim sup |x|−α
|u(x)| < ∞ as |x| → ∞ for some α ∈ [0, 1/7).† Bibliography: 10 titles. 相似文献
104.
The reaction of trifold protected cyclen with fluorinated dinitroarenes yields aryl‐substituted or aryl‐bridged cyclen derivatives in good yield. The two arene nitro groups, necessary for the nucleophilic aromatic substitution, are subsequently selectively reduced to amines and further functionalized by amide formation. As an example, a cyclen derivative bearing a heterocyclic oligoamide with potential DNA binding ability was prepared. 相似文献
105.
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107.
S. Issing F. Fuchs C. Ziereis E. Batke A. Pimenov Y. Vu. Ivanov A. A. Mukhin J. Geurts 《The European Physical Journal B - Condensed Matter and Complex Systems》2010,73(3):353-360
A systematic and detailed study of Raman and infrared active lattice excitations in the orthorhombic multiferroic manganite
Eu1−xYxMnO3 (0 ≤ x ≤ 0.5) was carried out at room temperature. For the infrared active phonon modes the eigenfrequencies, damping constants
and oscillator strengths were analyzed by Fourier-Transform Infrared Spectroscopy in the far infrared frequency range. For
the Raman active phonons the same analysis for eigenfrequencies and damping constants was carried out using Raman spectroscopy
in the range from 200 cm−1 to 700 cm−1. Y doping leads to mode-dependent phonon frequency shifts up to 8%. These are interpreted in terms of the interplay between
the decrease of the reduced ion masses and the axis-dependent change of bond lengths. The latter leads to a bond softening
along the a-axis and a strengthening along the c-axis, for which the highest phonon frequency increase is observed. The application
of both Raman and Infrared Spectroscopy gives us sensitivity not only to symmetry properties via the selection rules but also
to the involvement of different ion types within the unit cell. It is clearly shown that the disorder induced effects are
of minor impact on the lattice properties and solely detected on the rare earth sites. The MnO6 octahedra remain unaffected and show the same behavior as in the stochiometric RMnO3 making Eu1−xYxMnO3 an excellent model system for a quasi-continuous fine-tuning of the lattice parameters relevant for the appearance of multiferroicity. 相似文献
108.
A. Fuchs M. Bender U. Plachetka L. Kock N. Koo T. Wahlbrink H. Kurz 《Current Applied Physics》2008,8(6):669-674
In the past decade nanoimprint has been developed to a serious alternative for next generation lithography (NGL). In this work, the most recent developments of UV-nanoimprint Lithography (UV-NIL) with special emphasis to the work accomplished at AMO and the IHT-RWTH Aachen are reviewed and functional applications demonstrated. Further the potentials of various UV-NIL concepts are evaluated and possible interests in certain application areas are discussed. 相似文献
109.
Michael Bildhauer Martin Fuchs Victor Osmolovskii 《Mathematical Methods in the Applied Sciences》2002,25(2):149-178
We consider the problem of minimizing among functions u:?d?Ω→?d, u∣?Ω=0, and measurable subsets E of Ω. Here fh+, f? denote quadratic potentials defined on Ω¯×{symmetric d×d matrices}, h is the minimum energy of fh+ and ε(u) is the symmetric gradient of the displacement field u. An equilibrium state û, Ê of J(u,E) is called one‐phase if E=?? or E=Ω, two‐phase otherwise. For two‐phase states, σ∣?E∩Ω∣ measures the effect of the separating surface, and we investigate the way in which the distribution of phases is affected by the choice of the parameters h??, σ>0. Additional results concern the smoothness of two‐phase equilibrium states and the behaviour of inf J(u,E) in the limit σ↓0. Moreover, we discuss the case of additional volume force potentials, and extend the previous results to non‐zero boundary values. Copyright © 2002 John Wiley & Sons, Ltd. 相似文献
110.
M. Bildhauer M. Fuchs V. G. Osmolovskii 《Mathematical Methods in the Applied Sciences》2002,25(4):289-308
We consider the problem of minimizing 0<p<1, h∈?, σ>0, among functions u:?d?Ω→?d, u∣?Ω=0, and measurable characteristic functions χ:Ω→?. Here ?+h, ??, denote quadratic potentials defined on the space of all symmetric d×d matrices, h is the minimum energy of ?+h and ε(u) denotes the symmetric gradient of the displacement field. An equilibrium state û, χ?, of I [·,·,h, σ] is termed one‐phase if χ?≡0 or χ?≡1, two‐phase otherwise. We investigate the way in which the distribution of phases is affected by the choice of the parameters h and σ. Copyright 2002 John Wiley & Sons, Ltd. 相似文献