Micromechanical cantilevers were validated for the detection of antibody peptide interactions. For this purpose, gold-coated microcantilevers were chemically functionalized with an analog of the myc-tag decapeptide. Chemoselective covalent coupling of the peptide to the gold surface occurred via the sulfhydryl-group of a C-terminal cystein residue. In order to verify the surface functionalization by epifluorescence microscopy, a carboxyfluorescein reporter group was attached to the N-terminus. Binding of an anti-myc-tag antibody caused a bending of the microcantilever, resulting from a change in surface stress. The bending was recorded optically from the deflection of a laser beam. In order to compensate for bending due to nonspecific interactions, a nonfunctionalized cantilever serving as a reference was measured in parallel. A charge coupled device camera served as a position-sensitive detector, enabling the parallel and simultaneous detection of signals from an array of microcantilevers. The results validate microcantilevers for the label-free detection of antibody peptide interactions at physiological solvent conditions.

This paper systematically analyzes linear oscillators, e.g., spring-mass-damper systems or RLC-circuits that are controlled by an extension of a phase-locked loop (PLL). These systems are often used in measurement applications where the stability and dynamics directly influence the measurement quality. Therefore, a description of the control loop in terms of phase signals is sought. However, the classical oscillator turns into a highly nonlinear system when it is formulated in amplitude/phase-variables of its input and output signals. Up to now, there were made either ab-initio assumptions of slowly varying parameters or trial-and-error designs. The novel approach proposed in this paper derives a universally valid description in state space form which enables the use of standard methods of nonlinear system theory. Using this description, the stability of phase controlled oscillators is analyzed by means of Lyapunov functions. A linearization is applied in order to effectively design the controller and optimize the closed-loop dynamics. Simulations with the original nonlinear systems are conducted to justify the linear approach. Thereby, two application scenarios are under consideration: Tracking of the desired target value (target phase shift) and resonance tracking (changes of the system parameters). It is found that including the phase dynamics of the oscillator significantly improves the description of the closed-loop behavior. Finally, the results are validated experimentally for an application measuring the viscosity of fluids.

For the development of all‐solid‐state batteries (ASSBs), it is of major importance to identify scalable process routes, to define limits of the processing technologies, and to investigate how the electrochemical performance can be influenced by the manufacturing process. Herein, two scalable and sustainable production chains are presented, extrusion‐ and direct calendaring of composite cathode granules, which are suitable for industrial series production. Both process routes start with a melt granulation step to desagglomerate the carbon black to homogenize the cathode components. By adjusting the granulation process parameters the process time and, thus, the production costs can be reduced. The polymer solid electrolyte distribution induced by the process shows a considerable influence on the rate capability of the ASSB cells. The manufactured pouch cells reach ≈140 mAh g−1 at 0.1C and 75/50 mAh g−1 at 1C discharge rate and 80 °C for extruded‐calendered and directly calendered electrodes, respectively, which is comparable to other recent publications on laboratory scale.

Variational integrators are modern time-integration schemes based on a discretization of the underlying variational principle. They thus skip the direct formulation and time discretization of partial differential equations. In mechanics, Hamilton's Principle is approximated by an action sum whose variation should be equal to zero, resulting in discrete Euler-Lagrange Equations or equivalently in discrete Position-Momentum Equations. Variational integrators are, by design, structure preserving (symplecticity) and show excellent long-time behavior. In order to consider the coupling between mechanical and thermal quantities, Hamilton's principle is extended by using the notion of thermacy as thermal analogue to mechanical displacements. From this variational formulation, a variational integrator using the generalized trapezoidal rule is constructed exemplarily. A thermoelastic double pendulum with heat conduction serves as a model problem.

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This article describes the results of experimental evaluation of capabilities of a pin-force mathematical model for guided wave generation and sensing in elastic beam-like structures using MFC piezoelectric elements. It is found that the model provides an adequate and convenient tool for fast parametric study of wave excitation and propagation at a frequency range of practical interest. The model is tested against both MFC and laser vibrometer-based signal measurements; the upper frequency limits of applicability for both sensing methods are demonstrated.

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<p>From previous studies it is evident that decoupled simulations lack the ability to capture certain coupled effects, such as the Noordbergum effect or the Mandel-Cryer effect in a hydraulic-mechanical context. Thus, for detailed simulations of geotechnical or geological system, coupled simulations are usually chosen. For example, thermal-hydraulic-mechanical (THM) coupled systems, and even chemical and biological couplings (THMCB), are considered in simulations used to assess barrier integrity over long time spans in the context of geological waste disposal.</p><p>This paper is restricted to coupled hydraulic-mechanical (HM) systems. A monolithic approach is both stable and accurate for strongly coupled systems. However, as site-scale models of geological disposal facilities are also large in spatial dimensions, it is worth to investigate how staggered methods may cut down the computational costs. The fixed-stress split appears to be a promising approach for staggered schemes in terms of stability, consistency, accuracy, and efficiency.</p><p>While adding another iteration level in comparison to monolithic schemes, staggered schemes allow for lower-order approximation spaces, whereas monolithic schemes require Taylor-Hood elements resulting in a larger number of degrees of freedom per element. Both coupling schemes are implemented in the the open-source finite-element (FE) software OpenGeoSys and used to simulate a large-scale model, which is oriented towards a real site in planning in Russia. Simulation results are compared in terms of accuracy, coupling effects and performance.</p>