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101.
Elmar K. Tschegg Stefan Herndler Patrick Weninger Michael Jamek Stefanie Stanzl-Tschegg Heinz Redl 《Materials science & engineering. C, Materials for biological applications》2008,28(8):1203-1208
A testing method has been developed to characterize stiffness and permanent deformation of bone-implant systems. The system consists of an artificial tibia with simulated distal fracture stabilized by an unreamed intramedullary nail. This system was loaded with three different sequences at 2 Hz, each consisting of 40,000 sinusoidal cycles, simulating clinical relevant loading conditions. Evaluation of the results showed a stiffness of 2782 N/mm with a standard deviation of 311 N/mm and a permanent deformation of 0.64 mm with a standard deviation of 0.21 mm. The locking screws broke exclusively during the third loading sequence starting with the most proximal of the distal screws. The study provides a standard technique for biomechanical testing and a comparison of different bone/implant-systems avoiding the variability of cadaver bone tests. 相似文献
102.
103.
The drive in data storage technology towards utilizing magnetic films with lower magnetostriction (to reduce the magnetoelastic energy term) and reduced thickness has resulted in the requirement for more sensitive, reliable, and easy-to-use tools to monitor magnetostriction. A measurement tool based on an in-plane rotating and saturating magnetic field and laser-beam-deflection technique, which is able to meet these requirements, is described. The tool developed offers high accuracy, large dynamic range, long-term stability, simple sample insertion, and a fast, easy measurement procedure. With this tool, the measurement of small magnetostriction coefficients of thin soft-magnetic films can become a simple, fast, and reliable procedure, thus helping the development of magnetic thin-film production processes and routine composition control 相似文献
104.
105.
Cover Picture: Selective Inhibitors of the Protein Tyrosine Phosphatase SHP2 Block Cellular Motility and Growth of Cancer Cells in vitro and in vivo (ChemMedChem 5/2015) 下载免费PDF全文
106.
Wang Y. Bartelt H. Ecke W. Moerl K. Lehmann H. Schroeder K. Willsch R. Kobelke J. Rothhardt M. Spittel R. Shan L. Brueckner S. Jin W. Tan X. Jin L. 《Photonics Technology Letters, IEEE》2010,22(3):164-166
107.
The tetrasaccharide 4, a substructure of ganglioside GQ1balpha, shows a remarkable affinity for the myelin-associated glycoprotein (MAG) and was therefore selected as starting point for a lead optimization program. In our search for structurally simplified and pharmacokinetically improved mimics of 4, antagonists with modifications of the core disaccharide Galbeta(1-3)GalNAc, as well as the terminal alpha(2-3)- and the internal alpha(2-6)-linked neuraminic acid were synthesized and tested in target-based binding assays. Compared to the reference tetrasaccharide 4, the most potent antagonist 17 exhibits a 360-fold improved affinity. Furthermore, pharmacokinetic parameters such as stability in the cerebrospinal fluid, logD and permeation through the BBB indicate the drug-like properties of antagonist 17. 相似文献
108.
Tatiana A. Kolesnikova Dmitry A. Gorin Paulo Fernandes Stefanie Kessel Gennady B. Khomutov Andreas Fery Dmitry G. Shchukin Helmuth Möhwald 《Advanced functional materials》2010,20(7):1189-1195
A water suspension of nanocomposite microcapsules with embedded ZnO nanoparticles in the capsule shell is reported. The microcapsule morphology is characterized by confocal microscopy, TEM, SEM, and AFM before and after ultrasound treatment. A remarkably high capsule sensitivity to ultrasound is evidenced, and it is observed to grow with increasing number of ZnO nanoparticle layers in the nanocomposite shell. This effect is correlated with the mechanical properties of microcapsules measured with AFM. 相似文献
109.
Nashwa Abo Elneel Erkan Aksoy Dietmar Schroeder 《Analog Integrated Circuits and Signal Processing》2010,64(3):249-259
A novel adaptable analog/digital converter (ADC) that combines analog/digital conversion and entropy-coding for integrated
data compression and low-power operation is reported. The converter has high flexibility of operation in terms of adaptable
resolution, conversion rate and input signal statistics. This feature allows to adaptively react to changes of the situation
and to put the device in each case into the optimum configuration. The ADC has been realized in a 0.6 μm CMOS technology with
a peak resolution of 12 bit and 200 kS/s maximum sampling rate. A comprehensive power model of the converter is presented
that reflects precisely the power consumption determined from experiments. The model is very useful for optimizing the converter
configuration in the node of a wireless sensor network for specific situations. A feasible real-life application is demonstrated. 相似文献
110.
Adolf Heißner Stefanie Schmidt Burkhardt von Elsner 《Journal of the science of food and agriculture》2005,85(4):539-548
Covering the soil with plastic film is an important method to modify soil temperature and improve the conditions for plant growth. For the optimal use of films in horticulture, it is necessary to quantify this effect, which depends particularly on the optical properties of the film. Five films, used mainly for soil covering in asparagus cultivation, were tested by measuring the soil temperature as well as the transmittance and reflectance in the short‐ and long‐wavelength bands: ‘Taschenfolie schwarz/weiß’, a film with black and white surfaces and pockets for fastening; ‘Antitaufolie’, a film with anti‐condensation coating, ‘Solartherm plus Folie’, a film with black top and transparent sides; ‘MaterBi Folie’, a biodegradable film; and ‘Thermoplus Folie’, a black polyethylene with transparent sides. All films were produced in Germany. The temperature measurements were carried out under controlled irradiation (short‐wavelength band) and ambient temperature conditions in the laboratory: first, 182 W m?2 and 11 °C at a depth of 0.4 m, and second, 340 W m?2 at 20 °C. A significant relationship between the temperature increase or decrease by covering the soil with the film and the calculated apparent quantities of the reflectance in the short and long‐wavelength band was derived (r2 = 0.85, n = 12). Furthermore, first tests with a physical model were carried out to obtain basic information, which should be used in the development of strategies for film management in the field. Copyright © 2004 Society of Chemical Industry 相似文献