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51.
Wipf P  Maciejewski JP 《Organic letters》2008,10(19):4383-4386
Reductive cyclization of epoxides tethered to substituted anilines and aminopyridines in the presence of 3 mol % of titanocene dichloride and stoichiometric manganese metal promotes a radical annulation to form 3,3-disubstituted indolines and azaindolines.  相似文献   
52.
A new, flexible and selective protocol for the synthesis of new organofunctional silicon dendrons of the general formula EtOSi(CH2CH2SiMe2CH2CH2SiMe2R)3 (where R is an amine or epoxy substituent) has been developed. The title compounds have been efficiently obtained via Karstedt platinum‐catalysed hydrosilylation and linked to a glass surface. Modified solid supports are successfully applied in immobilization of proteins, especially monoclonal antibodies against a wide range of antigens. Copyright © 2015 John Wiley & Sons, Ltd.  相似文献   
53.
The paper deals with the Engineering Design that is a general methodology of a design process. It is assumed that a designer has to solve a design task as an inverse problem in an iterative way. After each iteration, a decision should be taken on the information that is called a centre of integration in a systematic design system. For this purpose, poly-optimal solutions may be used. The poly-optimization is presented and contrasted against the Multi Attribute Decision Making, and a set of the poly-optimal solutions is defined. Then Mechatronics is defined and its characteristics given, to prove that mechatronic design process vitally needs CAD tools. Three examples are quoted to demonstrate a key role of the poly-optimization in the mechatronic design.  相似文献   
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55.
A typical composition consisting of a low-molecular commercial epoxy resin based on bisphenol A and aliphatic polyamine hardener: triethylenetetramine was modified by replacing a part of the composition with up to 15 wt.% of low molecular weight bis(glycidylpropyl)- or bis(aminopropyl)-tetramethyldisiloxane. The reactivity of the compositions and basic properties of the resulting epoxy polymers, including glass transition temperature, storage modulus, thermal stability, impact and bending strengths, Brinell hardness, and flammability (limiting oxygen index) were evaluated.  相似文献   
56.
Paper is devoted to the solvability analysis of variational equations obtained by linearization of the Euler-Poisson equations for the symmetric rigid body with a fixed point on the equatorial plain. In this case Euler-Poisson equations have two pendulum like particular solutions. Symmetric heavy top is integrable only in four famous cases. In this paper is shown that a family of cases can be distinguished such that Euler-Poisson equations are not integrable but variational equations along particular solutions are solvable. The connection of this result with analysis made in XIX century by R. Liouville is also discussed.  相似文献   
57.
This paper presents an approach to the control system design of seat suspension systems for the active vibration attenuation. The paper presents the studies of the active vibration control strategy based on the reverse dynamics of force actuator and the primary controller. The multi-criteria optimization procedure is utilized in order to calculate the primary controller settings which subsequently define the vibro-isolation characteristics of active suspensions. As an example of the proposed control system design, the seat with a pneumatic suspension is investigated and its vibro-isolation properties are shaped by an appropriate selection of the controller settings.  相似文献   
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59.
The paper deals with an original control algorithm for semi-active and active suspension that are often used in automotive systems. The developed procedure assists in finding the structure of control system, which consists of the primary controller and calculates the desired active force. Then the desired force has to be approximately achieved by the semi-active or active element with calculated input signal using the inverse model. (© 2015 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim)  相似文献   
60.
Thermal analysis combined with mass spectrometry was applied to radiocarbon dating procedures (age determination of carbon-containing samples). Experiments carried out under an oxygen atmosphere were used to determine carbon content and combustion range of soil and wood samples. Composition of the shell sample and its decomposition were investigated. The quantification of CO2 formed by the oxidation of carbon was done by the application of pulse thermal analysis. Experiments carried out under an inert atmosphere determined the combustion range of coal with CuO as an oxygen source. To eliminate a possible source of contamination in the radiocarbon dating procedures the adsorption of CO2 by CuO was investigated. This revised version was published online in August 2006 with corrections to the Cover Date.  相似文献   
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