Stress-Dependent Optical Extinction in Low-Pressure Chemical Vapor Deposition Silicon Nitride Measured by Nanomechanical Photothermal Sensing.

Understanding optical absorption in silicon nitride is crucial for cutting-edge technologies like photonic integrated circuits, nanomechanical photothermal infrared sensing and spectroscopy, and cavity optomechanics. Yet, the origin of its strong dependence on the film deposition and fabrication process is not fully understood. This Letter leverages nanomechanical photothermal sensing to investigate optical extinction κ at a 632.

Functionalization of three-dimensional epitaxial graphene with metal nanoparticles.

We demonstrate the first successful functionalization of epitaxial three-dimensional graphene with metal nanoparticles. The functionalization is obtained by immersing three-dimensional graphene in a nanoparticle colloidal solution. This method is versatile and demonstrated here for gold and palladium, but can be extended to other types of nanoparticles.

Characterization of Surface Modifications in Oxygen Plasma-Treated Teflon AF1600.

We explore the surface properties of Teflon AF1600 films treated by oxygen plasma with various procedure parameters. Contact angle (CA) measurements, scanning electron microscopy (SEM), atomic force microscopy (AFM), and X-ray photoelectron microscopy (XPS) are employed to investigate the wetting behavior, surface topography, and chemical composition, respectively. While the etched thickness reveals a linear relationship to the applied plasma energy, the surface presents various wetting properties and topographies depending on the plasma energy: low advancing and zero receding CA (1 kJ), super high advancing and zero receding CA (2-3 kJ), and super high advancing and high receding CA (≥4.

Photothermal Microscopy and Spectroscopy with Nanomechanical Resonators.

In nanomechanical photothermal absorption spectroscopy and microscopy, the measured substance becomes a part of the detection system itself, inducing a nanomechanical resonance frequency shift upon thermal relaxation. Suspended, nanometer-thin ceramic or 2D material resonators are innately highly sensitive thermal detectors of localized heat exchanges from substances on their surface or integrated into the resonator itself. Consequently, the combined nanoresonator-analyte system is a self-measuring spectrometer and microscope responding to a substance's transfer of heat over the entire spectrum for which it absorbs, according to the intensity it experiences.

Nanomechanical Photothermal Near Infrared Spectromicroscopy of Individual Nanorods.

Understanding light-matter interaction at the nanoscale requires probing the optical properties of matter at the individual nanoabsorber level. To this end, we developed a nanomechanical photothermal sensing platform that can be used as a full spectromicroscopy tool for single molecule and single particle analysis. As a demonstration, the absorption cross-section of individual gold nanorods is resolved from a spectroscopic and polarization standpoint.

The Impact of Surface Discontinuities on MEMS Thermal Wind Sensor Accuracy.

A 2D calorimetric flow transducer is used to study distortions of the flow velocity field induced by small surface discontinuities around the chip. The transducer is incorporated into a matching recess of a PCB enabling wire-bonded interconnections to the transducer. The chip mount forms one wall of a rectangular duct.

Transduction of Single Nanomechanical Pillar Resonators by Scattering of Surface Acoustic Waves.

One of the challenges of nanoelectromechanical systems (NEMS) is the effective transduction of the tiny resonators. Vertical structures, such as nanomechanical pillar resonators, which are exploited in optomechanics, acoustic metamaterials, and nanomechanical sensing, are particularly challenging to transduce. Existing electromechanical transduction methods are ill-suited as they put constraints on the pillars' material and do not enable a transduction of freestanding pillars.

Nanoelectromechanical Infrared Spectroscopy with In Situ Separation by Thermal Desorption: NEMS-IR-TD.

We present a novel method for the quantitative analysis of mixtures of semivolatile chemical compounds. For the first time, thermal desorption is integrated directly with nanoelectromechanical infrared spectroscopy (NEMS-IR-TD). In this new technique, an analyte mixture is deposited via nebulization on the surface of a NEMS sensor and subsequently desorbed using heating under vacuum.

Intermodal coupling spectroscopy of mechanical modes in microcantilevers.

Atomic force microscopy (AFM) is highly regarded as a lens peering into the next discoveries of nanotechnology. Fundamental research in atomic interactions, molecular reactions, and biological cell behaviour are key focal points, demanding a continuous increase in resolution and sensitivity. While renowned fields such as optomechanics have marched towards outstanding signal-to-noise ratios, these improvements have yet to find a practical way to AFM.

Mask assistance to colorimetric sniffers for detection of Covid-19 disease using exhaled breath metabolites.

According to World Health Organization reports, large numbers of people around the globe have been infected or died for Covid-19 due to the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). Researchers are still trying to find a rapid and accurate diagnostic method for revealing infected people by low viral load with the overriding goal of effective diagnostic management. Monitoring the body metabolic changes is known as an effective and inexpensive approach for the evaluation of the infected people.

Germanium nanowire microbolometer.

Near-infrared detection is widely used for nondestructive and non-contact inspections in various areas, including thermography, environmental and chemical analysis as well as food and medical diagnoses. Common room temperature bolometer-type infrared sensors are based on architectures in them range, limiting miniaturization for future highly integrated 'More than Moore' concepts. In this work, we present a first principle study on a highly scalable and CMOS compatible bolometer-type detector utilizing Ge nanowires as the thermal sensitive element.

Temperature Dependence of Water Contact Angle on Teflon AF1600.

In this work, we investigate the change of contact angle (CA) of a water droplet during evaporation on a Teflon AF1600 surface in the temperature range between 20 and 80 °C under standard laboratory conditions. An almost constant initial CA and a significant increase of the stabilized CA have been observed. The results reveal a temperature-dependent CA change, mainly due to water adsorption on the solid surface.

Enzymeless voltammetric sensor for simultaneous determination of parathion and paraoxon based on Nd-based metal-organic framework.

The aim of this work is to fabricate a sensitive and novel enzymeless electrochemical sensor for the simultaneous determination of parathion and paraoxon using the Nd-UiO-66@MWCNT nanocomposite. For this purpose, Neodymium (Nd) was introduced into a Universitetet i Oslo (UiO-66) structure to construct Nd-UiO-66 and then, adding multi-walled carbon nanotubes to the Nd-UiO-66 to increase the electrocatalytic activity and surface area of the obtained composite. The Nd-UiO-66@MWCNT has numerous advantages like excellent conductivity, tunable texture, and large surface area and can be used as a distinctive structure for the construction of modified glassy carbon electrode (GCE) to enhance the charge-transfer and the efficiency of electrochemical sensors.

Construction and application of a novel electrochemical sensor for trace determination of uranium based on ion-imprinted polymers modified glassy carbon electrode.

In the present work, a novel electrochemical sensor modified glassy carbon electrode with ion-imprinted polymers (IIP-GCE) was applied for uranyl ions (UO) determination. Surface modifier was synthesized through precipitation polymerization method, using acrylic acid as a monomer, benzoyl peroxide (BPO) as initiator, and trimethylolpropane triacrylate (TMPTA) as cross-linker. A new uranyl-trans-3-(3-pyridyl) acrylic acid complex was employed, serving as an active and specific site on the synthesized modifier.

Robust Pressure Sensor in SOI Technology with Butterfly Wiring for Airfoil Integration.

Current research in the field of aviation considers actively controlled high-lift structures for future civil airplanes. Therefore, pressure data must be acquired from the airfoil surface without influencing the flow due to sensor application. For experiments in the wind and water tunnel, as well as for the actual application, the requirements for the quality of the airfoil surface are demanding.

Disposable Paper-Based Biosensors for the Point-of-Care Detection of Hazardous Contaminations-A Review.

The fast detection of trace amounts of hazardous contaminations can prevent serious damage to the environment. Paper-based sensors offer a new perspective on the world of analytical methods, overcoming previous limitations by fabricating a simple device with valuable benefits such as flexibility, biocompatibility, disposability, biodegradability, easy operation, large surface-to-volume ratio, and cost-effectiveness. Depending on the performance type, the device can be used to analyze the analyte in the liquid or vapor phase.

Optical Angular Sensor for Space Applications.

This paper describes a silicon/glass sensing structure for axial angle measurements. The presented optical angular sensor can statically measure the angle of any apparatus depending on the torsion of the optical component against the sensor housing. Core element of the sensor is an optical medium with an etched structure, which diffracts light from an LED according to the Fresnel equation.

Multi-scale characterisation of a ferroelectric polymer reveals the emergence of a morphological phase transition driven by temperature.

Ferroelectric materials exhibit a phase transition to a paraelectric state driven by temperature - called the Curie transition. In conventional ferroelectrics, the Curie transition is caused by a change in crystal symmetry, while the material itself remains a continuous three-dimensional solid crystal. However, ferroelectric polymers behave differently.

Electrochemiluminescent biosensor for ultrasensitive detection of lymphoma at the early stage using CD20 markers as B cell-specific antigens.

Herein, by taking advantage of the special binding of an aptamer to the membrane surface of a B cell and accumulation of the positive charges of a nanocomposite, including luminol-chitosan-platinum nanoparticles (L-Cs-Pt NPs), on the negatively charge of the aptamer phosphate backbone, a sensitive, simple, selective and rapid strategy for the detection of lymphoma cells by a new label-free electrogenerated chemiluminescence (ECL) aptasensor has been introduced. With increasing concentrations of B lymphoma cells, the nanocomposite detaches from the aptamer, leading to a decrease in the ECL of a luminol and HO system. With high loading of luminol and Pt NPs on a chitosan, together with the electrocatalytic effect of Pt NPs, enhanced sensitive detection of cancer cells with a limit of detection of 31 cells/mL was achieved.

Nanoelectromechanical Position-Sensitive Detector with Picometer Resolution.

Subnanometer displacement detection lays the solid foundation for critical applications in modern metrology. In-plane displacement sensing, however, is mainly dominated by the detection of differential photocurrent signals from photodiodes, with resolution in the nanometer range. Here, we present an integrated nanoelectromechanical in-plane displacement sensor based on a nanoelectromechanical trampoline resonator.

Ultrathin 2 nm gold as impedance-matched absorber for infrared light.

Thermal detectors are a cornerstone of infrared and terahertz technology due to their broad spectral range. These detectors call for efficient absorbers with a broad spectral response and minimal thermal mass. A common approach is based on impedance-matching the sheet resistance of a thin metallic film to half the free-space impedance.

Evaluation of Microfluidic Ceiling Designs for the Capture of Circulating Tumor Cells on a Microarray Platform.

The capture of circulating tumor cells (CTCs) is still a challenging application for microfluidic chips, as these cells are rare and hidden in a huge background of blood cells. Here, different microfluidic ceiling designs in regard to their capture efficiency for CTCs in model experiments and more realistic conditions of blood samples spiked with a clinically relevant amount of tumor cells are evaluated. An optimized design for the capture platform that allows highly efficient recovery of CTCs from size-based pre-enriched samples under realistic conditions is obtained.

Electrochemical biosensors for the detection of lung cancer biomarkers: A review.

Cancer is one of the most widespread challenges and important diseases, which has the highest mortality rate. Lung cancer is the most common type of cancer, so that about 25% of all cancer deaths are related to the lung cancer. The lung cancer is classified as two different types with different treatment methodology: the small cell lung carcinoma and nonsmall cell lung carcinoma are two categories of the lung cancer.

FEM-Analysis of 2D Micromachined Flow Transduers based on aGe-Thermistor Arrays and a Double Bridge Readout.

This paper reports on a design and simulation study aiming at high-accuracy 2D micromachined thermal flow transducers. The scope is restricted to micromachined devices featuring a square-shaped membrane incorporating central symmetric thin-film devices. A microthermistor array probed spatial excess temperature variations while the main heat supply was alternatively established by optional heating resistors or by pronounced self-heating of the thermistor devices.