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排序方式: 共有299条查询结果,搜索用时 46 毫秒
1.
Robert G. Surbella III Korey P. Carter Trevor D. Lohrey Dallas Reilly Mark Kalaj Bruce K. McNamara Jon Schwantes Rebecca J. Abergel 《Chemistry (Weinheim an der Bergstrasse, Germany)》2020,26(61):13819-13825
A new uranyl containing metal–organic framework, RPL-1 : [(UO2)2(C28H18O8)] . H2O (RPL for Radiochemical Processing Laboratory), was prepared, structurally characterized, and the solid-state photoluminescence properties explored. Single crystal X-ray diffraction data reveals the structure of RPL - 1 consists of two crystallographically unique three dimensional, interpenetrating nets with a 4,3-connected tbo topology. Each net contains large pores with an average width of 22.8 Å and is formed from monomeric, hexagonal bipyramidal uranyl nodes that are linked via 1,2,4,5-tetrakis(4-carboxyphenyl)benzene (TCPB) ligands. The thermal and photophysical properties of RPL-1 were investigated using thermogravimetric analysis and absorbance, fluorescence, and lifetime spectroscopies. The material displays excellent thermal stability and temperature dependent uranyl and TCPB luminescence. The framework is stable in aqueous media and due to the large void space (constituting 76 % of the unit cell by volume) can sequester organic dyes, the uptake of which induces a visible change to the color of the material. 相似文献
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Soft robots are bio-inspired, highly deformable robots with the ability to interact with workpieces in a manner that complements their hard robot counterparts. To develop practical applications and reproducible designs of soft robots, new models are necessary to describe their kinematics and dynamics. In the present work, we describe experimental and numerical investigations of a popular pneumatically-actuated soft continuum arm. These works enable us to derive constitutive relations and develop a rod model for large deformations of the arm that faithfully describes its bending behavior. We show how the resulting non-classical constitutive relation can be defined either through experiments or through quasi-static finite element simulations. With the help of this relation, the resulting rod model can be used to study the dynamics of the soft robot arm in a fast and tractable manner. (© 2016 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim) 相似文献
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Vladimir Gubala Jonathan Siegrist Ruairi Monaghan Brian O’Reilly Ram Prasad Gandhiraman Stephen Daniels David E. Williams Jens Ducrée 《Analytica chimica acta》2013
Herein a simple analytical method is presented for the characterization of biomolecule adsorption on cyclo olefin polymer (COP, trade name: Zeonor®) substrates which are widely used in microfluidic lab-on-a-chip devices. These Zeonor® substrates do not possess native functional groups for specific reactions with biomolecules. Therefore, depending on the application, such substrates must be functionalized by surface chemistry methods to either enhance or suppress biomolecular adsorption. This work demonstrates a microfluidic method for evaluating the adsorption of antibodies and oligonucleotides surfaces. The method uses centrifugal microfluidic flow-through chips and can easily be implemented using common equipment such as a spin coater. The working principle is very simple. The user adds 40 L of the solution containing the sample to the starting side of a microfluidic channel, where it is moved through by centrifugal force. Some molecules are adsorbed in the channel. The sample is then collected at the other end in a small reservoir and the biomolecule concentration is measured. As a pilot application, we characterized the adsorption of goat anti-human IgG and a 20-mer DNA on Zeonor®, and on three types of functionalized Zeonor: 3-aminopropyltriethoxysilane (APTES) modified surface with mainly positive charge, negatively charged surface with immobilized bovine serum albumin (BSA), and neutral, hydrogel-like film with polyethylene glycol (PEG) characteristics. This simple analytical approach adds to the fundamental understanding of the interaction forces in real, microfluidic systems. This method provides a straightforward and rapid way to screen surface compositions and chemistry, and relate these to their effects on the sensitivity and resistance to non-specific binding of bioassays using them. In an additional set of experiments, the surface area of the channels in this universal microfluidic chip was increased by precision milling of microscale trenches. This modified surface was then coated with APTES and tested for its potential to serve as a unique protein dilution feature. 相似文献
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In the 1950s and 1960s, Charles F. Taylor designed and tested various prototype one-wheeled vehicles. These machines were
stabilized and steered using gyroscopes. In this paper, a simple model of a one-wheeled vehicle is presented and analyzed.
This analysis explains the ability of these machines to exhibit stable steady motions.
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Norman R. Reilly 《Semigroup Forum》2009,78(1):157-182
It is shown that, within the class of Rees-Sushkevich varieties that are generated by completely (0-) simple semigroups over
groups of exponent dividing n, there is a hierarchy of varieties determined by the lengths of the products of idempotents that will, if they fall into
a group ℋ-class, be idempotent. Moreover, the lattice of varieties generated by completely (0-) simple semigroups over groups
of exponent dividing n, with the property that all products of idempotents that fall into group ℋ-classes are idempotent, is shown to be isomorphic
to the direct product of the lattice of varieties of groups with exponent dividing n and the lattice of exact subvarieties of a variety generated by a certain five element completely 0-simple semigroup. 相似文献