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Andreas Mark Nicolas Helfricht Astrid Rauh Matthias Karg Georg Papastavrou 《Small (Weinheim an der Bergstrasse, Germany)》2019,15(43)
The colloidal probe technique, which is based on the atomic force microscope, revolutionizes direct force measurements in many fields, such as interface science or biomechanics. It allows for the first time to determine interaction forces on the single particle or cell level. However, for many applications, important “blind spots” remain, namely, the possibility to probe interaction potentials for nanoparticles or complex colloids with a soft outer shell. Definitely, these are colloidal systems that are currently of major industrial importance and interest from theory. The here‐presented novel approach allows for overcome the aforementioned limitations. Its applicability has been demonstrated for 300 nm sized carboxylate‐modified latex particles as well as sub‐micron core–shell particles with a soft poly‐N‐isopropylacrylamide hydrogel shell and a rigid silica core. For the latter, which until now cannot be studied by the colloidal probe technique, determined is the temperature dependency of electrosteric and adhesion forces has been determined on the single particle level. 相似文献
994.
Josie Dzifa Akua Parrianen Andreas Papageorgiou Simon Doyle Enzo Pascale 《Journal of Low Temperature Physics》2018,193(3-4):113-119
We present the first published results of near-infrared single-photon detection in aluminium lumped element kinetic inductance detectors (LEKIDs). Using aluminium as a well-understood material that follows conventional superconductor theory, we discuss and validate a model that describes the energy-resolving performance of a LEKID to single-photon absorption events. We also discuss data analysis techniques used to extract single-photon detections from noisy data. We measure an energy resolution of 662 meV for a 1550 nm photon source which is in close agreement to our model predictions for this non-optimised device limited by generation–recombination noise. 相似文献
995.
Determining and keeping track of a material’s mechanical performance is very important for safety in the aerospace industry. The mechanical strength of alloy materials is precisely quantified in terms of its stress–strain relation. It has been proven that frequency-domain photothermoacoustic (FD-PTA) techniques are effective methods for characterizing the stress–strain relation of metallic alloys. PTA methodologies include photothermal (PT) diffusion and laser thermoelastic photoacoustic ultrasound (PAUS) generation which must be separately discussed because the relevant frequency ranges and signal detection principles are widely different. In this paper, a detailed theoretical analysis of the connection between thermoelastic parameters and stress/strain tensor is presented with respect to FD-PTA nondestructive testing. Based on the theoretical model, a finite element method (FEM) was further implemented to simulate the PT and PAUS signals at very different frequency ranges as an important analysis tool of experimental data. The change in the stress–strain relation has an impact on both thermal and elastic properties, verified by FEM and results/signals from both PT and PAUS experiments. 相似文献
996.
OR Spectrum - This paper deals with a special vehicle routing problem with backhauls where customers may want to receive items from a depot and, at the same time, return items back to the depot.... 相似文献
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Milica Košević Srecko Stopic Andreas Bulan Jürgen Kintrup Reiner Weber Jasmina Stevanović Vladimir Panić Bernd Friedrich 《Advanced Powder Technology》2017,28(1):43-49
Synthesis and subsequent deposition of sub-micron spherical RuO2/TiO2 particles onto titanium were performed by continuous process in two connected reactors, exclusively applied for this purpose. Synthesis of particles was achieved by ultrasonic spray pyrolysis method in the first reactor. The deposition of thus produced RuO2/TiO2 onto an expanded titanium substrate was performed at 500 °C afterwards in the second, specially constructed, reactor equipped by high-voltage electrostatic field. Basic electrochemical properties of the obtained RuO2/TiO2 particles were checked in a form of the coating on Ti deposited from the suspension of the material produced in the first reactor. Thus prepared anode was investigated by cyclic voltammetry (CV), polarization measurements in O2 (OER) and Cl2 (CER) evolution and the accelerated stability test in diluted chloride solution. The morphology and composition of the deposited RuO2/TiO2 were checked by scanning electron microscopy/energy dispersive X-ray spectroscopy analysis. Analysis of the results obtained for OER and CER showed that Tafel slopes for these reactions were in accordance with the values for this kind of material. The CV response was of usual characteristics too. The accelerated stability test revealed acceptable anode stability. 相似文献
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Dielectrophoresis‐Assisted Integration of 1024 Carbon Nanotube Sensors into a CMOS Microsystem 下载免费PDF全文
Florent Seichepine Jörg Rothe Alexandra Dudina Andreas Hierlemann Urs Frey 《Advanced materials (Deerfield Beach, Fla.)》2017,29(17)
Carbon‐nanotube (CNT)‐based sensors offer the potential to detect single‐molecule events and picomolar analyte concentrations. An important step toward applications of such nanosensors is their integration in large arrays. The availability of large arrays would enable multiplexed and parallel sensing, and the simultaneously obtained sensor signals would facilitate statistical analysis. A reliable method to fabricate an array of 1024 CNT‐based sensors on a fully processed complementary‐metal‐oxide‐semiconductor microsystem is presented. A high‐yield process for the deposition of CNTs from a suspension by means of liquid‐coupled floating‐electrode dielectrophoresis (DEP), which yielded 80% of the sensor devices featuring between one and five CNTs, is developed. The mechanism of floating‐electrode DEP on full arrays and individual devices to understand its self‐limiting behavior is studied. The resistance distributions across the array of CNT devices with respect to different DEP parameters are characterized. The CNT devices are then operated as liquid‐gated CNT field‐effect‐transistors (LG‐CNTFET) in liquid environment. Current dependency to the gate voltage of up to two orders of magnitude is recorded. Finally, the sensors are validated by studying the pH dependency of the LG‐CNTFET conductance and it is demonstrated that 73% of the CNT sensors of a given microsystem show a resistance decrease upon increasing the pH value. 相似文献