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21.
Light-weight robots are advantageous considering the low energy consumption and the low material cost. However, in light-weight structures significant oscillations can occur which make the control very challenging. Objective of this research is end-effector trajectory tracking of a parallel manipulator with flexible links. Hereby, only the manipulator's drives are used, and no additional actuation on the flexible bodies is considered. For accurate trajectory tracking, feedforward control of the manipulator is used based on inverse dynamics and servo-constraints, combined with feedback control of the drive positions. (© 2016 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim) 相似文献
22.
Polymer brushes orthogonally derivatized with oxotitanium and nitrilotriacetate-Fe(III) groups enrich both mono- and multi-phosphorylated peptides for mass spectrometry analysis. 相似文献
23.
We report a steady-state theory for the evaluation of electrostatic interactions between identical or dissimilar spherical soft multi-layered (bio)particles, e.g. microgels or microorganisms. These generally consist of a rigid core surrounded by concentric ion-permeable layers that may differ in thickness, soft material density, chemical composition and degree of dissociation for the ionogenic groups. The formalism allows the account of diffuse interphases where distributions of ionogenic groups from one layer to the other are position-dependent. The model is valid for any number of ion-permeable layers around the core of the interacting soft particles and covers all limiting situations in terms of nature of interacting particles, i.e. homo- and hetero-interactions between hard, soft or entirely porous colloids. The theory is based on a rigorous numerical solution of the non-linearized Poisson-Boltzmann equation including radial and angular distortions of the electric field distribution within and outside the interacting soft particles in approach. The Gibbs energy of electrostatic interaction is obtained from a general expression derived following the method by Verwey and Overbeek based on appropriate electric double layer charging mechanisms. Original analytical solutions are provided here for cases where interaction takes place between soft multi-layered particles whose size and charge density are in line with Deryagin treatment and Debye-Hückel approximation. These situations include interactions between hard and soft particles, hard plate and soft particle or soft plate and soft particle. The flexibility of the formalism is highlighted by the discussion of few situations which clearly illustrate that electrostatic interaction between multi-layered particles may be partly or predominantly governed by potential distribution within the most internal layers. A major consequence is that both amplitude and sign of Gibbs electrostatic interaction energy may dramatically change depending on the interplay between characteristic Debye length, thickness of ion-permeable layers and their respective protolytic features (e.g. location, magnitude and sign of charge density). This formalism extends a recent model by Ohshima which is strictly limited to interaction between soft mono-shell particles within Deryagin and Debye-Hückel approximations under conditions where ionizable sites are completely dissociated. 相似文献
24.
Inhibition of corrosion of commercial mild steel in presence of tetrazole derivatives in acid medium
V. Violet Dhayabaran I. Sharmila Lydia J. Princy Merlin P. Srirenganayaki 《Ionics》2004,10(1-2):123-125
The inhibitive influence of tetrazole derivatives namely, 1-(91-acridinyl)-5-(4′-aminophenyl) tetrazole, 1-(9′-acridinyl)-5-(4′-hydroxy phenyl) tetrazole and 1-(9′-acridinyl)-5-(4′-chlorophenyl)
tetrazole on the corrosion of commercial mild steel in 1 N hydrochloric acid medium was studied by weight loss method. The
monolayer adsorption has been confirmed by fitting the data to the Langmuir adsorption isotherm. Weight loss studies have
been carried out at 303K, 318K and 333K. Thermodynamic parameters like heat of adsorption, activation energy and free energy
change have been calculated. The maximum inhibition of efficiency of tetrazole derivatives, 1-(9′-acridinyl)-5-(4′-amoinophenyl)
tetrazole, 1-(9′acridinyl)-5-(4′-hydroxyphenyl) tetrazole and 1-(9′-acridinyl)-5-(4′-Chlorphenyl) tetrazole was found to be
60.59%, 89.00% and 92.74, respectively.
Paper presented at the 2nd International Conference on Ionic Devices, Anna University, Chennai, India, Nov. 28–30, 2003. 相似文献
25.
V. Violet Dhayabaran J. Princy Merlin I. Sharmila Lydia R. Shanthi R. Sivaraj 《Ionics》2004,10(3-4):288-290
The influence of Fluorescein in conjunction with calcium oxide on the corrosion of Aluminium in 1.0 N NaOH was studied by
galvanostatic studies and weight loss studies. It has been found that the inhibition of corrosion of aluminium increased with
the increasing concentration of the inhibitor. The maximum inhibition efficiency of fluorescein alone was found to be 30.80%.
However, the addition of calcium oxide increased the maximum inhibition efficiency to 53.71%. The corrosion process was found
to be under the anodic control, in the presence or in the absence of inhibitor. The inhibition was found to be mixed type.
Paper presented at the 2nd International Conference on Ionic Devices, Anna University, Chennai, Inida, Nov. 28–30, 2003. 相似文献
26.
The change in reflectivity of a transporming sample of V3Si between 19 and 11.5 K exhibits not only the expected superconducting gap behavior (at 4 < ?ω < 6 meV) but unusual structure between 6 and 25 meV. One possible cause is the Holstein absorption process which would indicate an unexpected peak in the phonon parameter α2F at 6 ± 2 meV. Data at 19 and 30 K show that no change in reflectivity due to the structural transformation (~ 21 K) occurs to within ≈ over the same energy range. 相似文献
27.
Esters and chlorides of oxalic mono-esters can be estimated volumetrically. After saponification precipitation is carried out by means of a calcium chloride solution, the excess of which is measured by chelatometry. 相似文献
28.
We discuss the assignment made in a previous paper by D. Hulin and C. Benoit à la Guillaume concerning one of the lines observed in the photoluminescence of EuO. We present further experimental evidence which discards the involvement of magnons in the luminescence process. 相似文献
29.
Franoise Lambert Michel Ellenberger Louis Merlin Yves Cohen 《Magnetic resonance in chemistry : MRC》1975,7(6):266-273
The proton magnetic resonance spectra of catechol, epinephrine, dopamine, synephrine, tyramine and amphetamine have been analysed by computer simulation. The chemical shifts and coupling constants are discussed, with their molecular implications. Convenient parameters are introduced for the additivity of substituent effects on chemical shifts of aromatic protons. The additivity rule of coupling constants is extended to these compounds. 相似文献
30.
The radiochemical purity of the113
mIn-DTPA complex is determined by two methods whose principle is different: filtration on ‘Sephadex” gel, and ascending paperchromatography.
The two techniques give slightly different values for non-complexed indium; any way less than 5% mean value. They show that
the reproducibility of the method used to prepare the compound is satisfactory.
相似文献