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1.	Sepehri, Sobhan, 1986, et al. (författare) Volume-amplified magnetic bioassay integrated with microfluidic sample handling and high-Tc SQUID magnetic readout 2018 Ingår i: APL Bioengineering. - : AIP Publishing. - 2473-2877. ; 2:1 Tidskriftsartikel (refereegranskat)abstract A bioassay based on a high-Tc superconducting quantum interference device (SQUID) reading out functionalized magnetic nanoparticles (fMNPs) in a prototype microfluidic platform is presented. The target molecule recognition is based on volume amplification using padlock-probe-ligation followed by rolling circle amplification (RCA). The MNPs are functionalized with single-stranded oligonucleotides, which give a specific binding of the MNPs to the large RCA coil product, resulting in a large change in the amplitude of the imaginary part of the ac magnetic susceptibility. The RCA products from amplification of synthetic Vibrio cholera target DNA were investigated using our SQUID ac susceptibility system in microfluidic channel with an equivalent sample volume of 3 μl. From extrapolation of the linear dependence of the SQUID signal versus concentration of the RCA coils, it is found that the projected limit of detection for our system is about 1.0 e5 RCA coils (0.2e−18 mol), which is equivalent to 66 fM in the 3 μl sample volume. This ultra-high magnetic sensitivity and integration with microfluidic sample handling are critical steps towards magnetic bioassays for rapid detection of DNA and RNA targets at the point of care.
2.	Chen, Zhe, et al. (författare) Nano-scale characterization of white layer in broached Inconel 718 2017 Ingår i: Materials Science & Engineering A: Structural Materials: Properties, Microstructure and Processing. - Amsterdam : Elsevier BV. - 0921-5093 .- 1873-4936. ; 684, s. 373-384 Tidskriftsartikel (refereegranskat)abstract The formation mechanism of white layers during broaching and their mechanical properties are not well investigated and understood to date. In the present study, multiple advanced characterization techniques with nano-scale resolution, including transmission electron microscopy (TEM), transmission Kikuchi diffraction (TKD), atom probe tomography (APT) as well as nano-indentation, have been used to systematically examine the microstructural evolution and corresponding mechanical properties of a surface white layer formed when broaching the nickel-based superalloy Inconel 718.TEM observations showed that the broached white layer consists of nano-sized grains, mostly in the range of 20–50 nm. The crystallographic texture detected by TKD further revealed that the refined microstructure is primarily caused by strong shear deformation. Co-located Al-rich and Nb-rich fine clusters have been identified by APT, which are most likely to be γ′ and γ′′ clusters in a form of co-precipitates, where the clusters showed elongated and aligned appearance associated with the severe shearing history. The microstructural characteristics and crystallography of the broached white layer suggest that it was essentially formed by adiabatic shear localization in which the dominant metallurgical process is rotational dynamic recrystallization based on mechanically-driven subgrain rotations. The grain refinement within the white layer led to an increase of the surface nano-hardness by 14% and a reduction in elastic modulus by nearly 10% compared to that of the bulk material. This is primarily due to the greatly increased volume fraction of grain boundaries, when the grain size was reduced down to the nanoscale.
3.	Eivazihollagh, Alireza, et al. (författare) On chelating surfactants : Molecular perspectives and application prospects 2019 Ingår i: Journal of Molecular Liquids. - : Elsevier BV. - 0167-7322 .- 1873-3166. ; 278, s. 688-705 Tidskriftsartikel (refereegranskat)abstract Chelating agents, molecules that very strongly coordinates certain metal ions, are used industrially as well as in consumer products to minimize disturbances and increase performance of reactions and applications. The widely used sequestering agents, nitrilotriacetic acid (NTA), ethylenediaminetetraacetic acid (EDTA) and diethylenetriaminepentaacetic acid (DTPA) belong to this branch of readily water-soluble compounds. When these chemical structures also have hydrophobic parts, they are prone to adsorb at air-water interfaces and to self-assemble. Such bifunctional molecules can be called chelating surfactants and will have more extended utilization prospects than common chelating agents or ordinary ionic surfactants. The present review attempts to highlight the fundamental behavior of chelating surfactants in solution and at interfaces, and their very specific interactions with metal ions. Methods to recover chelating surfactants from metal chelates are also described. Moreover, utilization of chelating surfactants in applications for metal removal in environmental engineering and mineral processing, as well as for metal control in the fields of biology, chemistry and physics, is exemplified and discussed.
4.	Decrop, Deborah, et al. (författare) Single-step manufacturing of femtoliter microwell arrays in a novel surface energy mimicking polymer 2015 Ingår i: 18th International Conference on Solid-State Sensors, Actuators and Microsystems (IEEE TRANSDUCER 2015). - : IEEE. Konferensbidrag (refereegranskat)abstract We report a novel polymer material formulation and stamp-molding technique that enable rapid single-step manufacturing of hydrophilic-in-hydrophobic microwell arrays. We developed a modified thiol-ene-epoxy polymer (mOSTE+) formulation that mimics the surface energy of its mold during polymerization. The polymer inherits the surface energy from the mold through molecular self-assembly, in which functional monomers self-assemble at the interface between the liquid prepolymer and the mold surface. Combining this novel mOSTE+ material with a stamp-molding process leads to simultaneous surface energy mimicking and micro-structuring. This method was used to manufacture microwells with hydrophilic bottom and hydrophobic sidewall, depressed in a surrounding hydrophobic surface. The microwell arrays were successfully tested for the self-assembly of 62’000 femtoliter-droplets. Such femtoliter droplet arrays are useful for, e.g., digital ELISA and single cell/molecule analysis applications.
5.	Surendiran, Pradheebha, et al. (författare) Solving Exact Cover Instances with Molecular-Motor-Powered Network-Based Biocomputation 2022 Ingår i: ACS Nanoscience Au. - : American Chemical Society (ACS). - 2694-2496 .- 2694-2496. Tidskriftsartikel (refereegranskat)abstract Information processing by traditional, serial electronic processors consumes an ever-increasing part of the global electricity supply. An alternative, highly energy efficient, parallel computing paradigm is network-based biocomputation (NBC). In NBC a given combinatorial problem is encoded into a nanofabricated, modular network. Parallel exploration of the network by a very large number of independent molecular-motor-propelled protein filaments solves the encoded problem. Here we demonstrate a significant scale-up of this technology by solving four instances of Exact Cover, a nondeterministic polynomial time (NP) complete problem with applications in resource scheduling. The difficulty of the largest instances solved here is 128 times greater in comparison to the current state of the art for NBC.
6.	Pardon, Gaspard, 1983- (författare) From Macro to Nano : Electrokinetic Transport and Surface Control 2014 Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract Today, the growing and aging population, and the rise of new global threats on human health puts an increasing demand on the healthcare system and calls for preventive actions. To make existing medical treatments more efficient and widely accessible and to prevent the emergence of new threats such as drug-resistant bacteria, improved diagnostic technologies are needed. Potential solutions to address these medical challenges could come from the development of novel lab-on-chip (LoC) for point-of-care (PoC) diagnostics.At the same time, the increasing demand for sustainable energy calls for the development of novel approaches for energy conversion and storage systems (ECS), to which micro- and nanotechnologies could also contribute.This thesis has for objective to contribute to these developments and presents the results of interdisciplinary research at the crossing of three disciplines of physics and engineering: electrokinetic transport in fluids, manufacturing of micro- and nanofluidic systems, and surface control and modification. By combining knowledge from each of these disciplines, novel solutions and functionalities were developed at the macro-, micro- and nanoscale, towards applications in PoC diagnostics and ECS systems.At the macroscale, electrokinetic transport was applied to the development of a novel PoC sampler for the efficient capture of exhaled breath aerosol onto a microfluidic platform.At the microscale, several methods for polymer micromanufacturing and surface modification were developed. Using direct photolithography in off-stoichiometry thiol-ene (OSTE) polymers, a novel manufacturing method for mold-free rapid prototyping of microfluidic devices was developed. An investigation of the photolithography of OSTE polymers revealed that a novel photopatterning mechanism arises from the off-stoichiometric polymer formulation. Using photografting on OSTE surfaces, a novel surface modification method was developed for the photopatterning of the surface energy. Finally, a novel method was developed for single-step microstructuring and micropatterning of surface energy, using a molecular self-alignment process resulting in spontaneous mimicking, in the replica, of the surface energy of the mold.At the nanoscale, several solutions for the study of electrokinetic transport toward selective biofiltration and energy conversion were developed. A novel, comprehensive model was developed for electrostatic gating of the electrokinetic transport in nanofluidics. A novel method for the manufacturing of electrostatically-gated nanofluidic membranes was developed, using atomic layer deposition (ALD) in deep anodic alumina oxide (AAO) nanopores. Finally, a preliminary investigation of the nanopatterning of OSTE polymers was performed for the manufacturing of polymer nanofluidic devices.
7.	Das, Atanu Kumar, et al. (författare) Applications of organic-based nanocomposites in corrosion protection 2023 Ingår i: Nanocomposites-Advanced Materials for Energy and Environmental Aspects. - : Elsevier. - 9780323997041 ; , s. 579-590 Bokkapitel (övrigt vetenskapligt/konstnärligt)abstract Corrosion protection is one of the utmost aims for the reduction of maintenance costs with higher production for the industry. The conventional toxic chromate-based coating is an environmental concern, which has led researchers to develop an organic-based coating with higher anticorrosive performance. The incorporation of nanocomposite increases the adhesion capability of the coating to the metal surface leading to protecting the metal from corrosion. Nanocomposites have novel mechanical and electrochemical properties. The type of nanocomposites depends on the type of nanostructured filler. The performance of nanocomposite coating depends on the types of nanoparticles and additives, the concentration of the dispersed particles, and the mixing processes. In this chapter, nanocellulose-based nanocomposites, their synthesis, and performance against corrosion protection have been discussed. The potential of these nanocomposites as corrosion inhibitors has been pointed out as well.
8.	Sun, Rui, et al. (författare) Highly Porous Amorphous Calcium Phosphate for Drug Delivery and Bio-Medical Applications 2020 Ingår i: Nanomaterials. - : MDPI. - 2079-4991. ; 10:1 Tidskriftsartikel (refereegranskat)abstract Amorphous calcium phosphate (ACP) has shown significant effects on the biomineralization and promising applications in bio-medicine. However, the limited stability and porosity of ACP material restrict its practical applications. A storage stable highly porous ACP with Brunauer–Emmett–Teller surface area of over 400 m2/g was synthesized by introducing phosphoric acid to a methanol suspension containing amorphous calcium carbonate nanoparticles. Electron microscopy revealed that the porous ACP was constructed with aggregated ACP nanoparticles with dimensions of several nanometers. Large angle X-ray scattering revealed a short-range atomic order of <20 Å in the ACP nanoparticles. The synthesized ACP demonstrated long-term stability and did not crystallize even after storage for over 14 months in air. The stability of the ACP in water and an α-MEM cell culture medium were also examined. The stability of ACP could be tuned by adjusting its chemical composition. The ACP synthesized in this work was cytocompatible and acted as drug carriers for the bisphosphonate drug alendronate (AL) in vitro. AL-loaded ACP released 25% of the loaded AL in the first 22 days. These properties make ACP a promising candidate material for potential application in biomedical fields such as drug delivery and bone healing.
9.	Das, Atanu Kumar, et al. (författare) Natural Fiber-based Nanocomposites as Corrosion Inhibitors 2022 Ingår i: Anticorrosive Nanomaterials. - Cambridge : Royal Society of Chemistry (RSC). ; :56, s. 191-206 Bokkapitel (övrigt vetenskapligt/konstnärligt)abstract Corrosion constitutes one of the troublesome issues in different industries,Â i.e., automotive, marine, construction, oil and gas. Protection from corrosion aims at reducing maintenance costs with higher production for the industry. Due to high toxicity, chromate-based coatings remain an environmental concern. This has necessitated the development of an organic-based coating with higher anti-corrosive performance. The adhesion capability of coating on metal surfaces can be improved through the incorporation of nanocomposites, which in turn can protect the metal from corrosion. Owing to their novel mechanical and electrochemical properties, types of nanocomposites dictate the types of nanostructured filler. The inclusion of cellulose nanocrystal (CNC) in epoxy-Zn rich coating shows better anti-corrosive performance for mild steel. In addition, silver nanoparticles and chitosan-based nanocomposite coating can protect mild steel from corrosion. However, the performance of the nanocomposite coating depends on the types of nanoparticles and additives, the concentration of the dispersed particles and mixing processes. In this chapter, the use of natural fiber-based nanocomposites in corrosion protection, and their synthesis and performance have been discussed. Alongside this, the potential of natural fiber-based nanocomposites for corrosion protection has been pointed out.
10.	Mellin, Pelle, 1985-, et al. (författare) Nano-sized by-products from metal 3D printing, composite manufacturing and fabric production 2016 Ingår i: Journal of Cleaner Production. - Sweden : Elsevier. - 0959-6526 .- 1879-1786. ; 139, s. 1224-1233 Tidskriftsartikel (refereegranskat)abstract Recently, the health and environmental perspective of nano-materials has gained attention. Most previous work focused on Engineered Nanoparticles (ENP). This paper examines some recently introduced production routes in terms of generated nano-sized by-products. A discussion on the hazards of emitting such particles and fibers is included. Fine by-products were found in recycled metal powder after 3D printing by Selective Laser Melting (SLM). The process somehow generated small round metal particles (~1e2 mm) that are possibly carcinogenic and respirable, but not small enough to enter by skin-absorption. With preventive measures like closed handling and masks, any health related effects can be prevented. The composite manufacturing in particular generated ceramic and carbonaceous particles that are very small and respirable but do not appear to be intrinsically toxic. The smallest features in agglomerates were about 30 nm. Small particles and fibers that were not attached in agglomerates were found in a wide range of sizes, from 1 μm and upwards. Preventive measures like closed handling and masks are strongly recommended. In contrast, the more traditional production route of fabric production is investigated. Here, brushing residue and recycled wool from fabric production contained few nano-sized by-products.
11.	Schodek, Daniel L, et al. (författare) Nanomaterials, nanotechnologies and design : an introduction for engineers and architects 2016 Bok (övrigt vetenskapligt/konstnärligt)
12.	Palo-Nieto, Carlos, 1985-, et al. (författare) Functionalization of cellulose nanofibrils to develop novel ROS-sensitive biomaterials 2023 Ingår i: Materials Advances. - : Royal Society of Chemistry. - 2633-5409. ; 4:6, s. 1555-1565 Tidskriftsartikel (refereegranskat)abstract Wood derived cellulose nanofibrils (CNFs) have emerged as an interesting material for biomedical applications. Functionalization of the nanofibrils with bioactive molecules is a potent tool to tailor CNF materials for specific applications in biomedicine. The present work proposes the functionalization of CNFs with a reactive oxygen species (ROS)-sensitive oligopeptide to develop a novel CNF-based material for the treatment of medical conditions associated with high levels of ROS such as chronic wounds. Oligoproline peptides of two different lengths (5 and 10 proline units) were covalently incorporated onto the CNF surface, several water-based chemical approaches were explored and the reaction conditions to maximize peptide substitution and the degree of fibre crosslinking were optimized. The chemical structure, degree of peptide substitution, degree of fibre crosslinking, surface morphology and ROS-sensitivity of the oligoproline–CNF materials were characterized. Double-crosslinked CNF hydrogels (Ca2+–oligoproline–CNF) were further prepared and the ability of the hydrogels to protect cells from an oxidative environment was investigated in vitro with human dermal fibroblasts, as a first evaluation of the potential of the novel CNF material to be used in chronic wound therapies. Optimization of the reaction conditions resulted in a degree of peptide substitution of 102 ± 10 μmol g−1 CNF irrespective of the oligoproline length and a degree of crosslinking of 55–80% depending on the number of proline units. The results showed that the oligoproline covalently attached to CNFs via carbodiimide chemistry maintained its ability to respond to ROS and that the responsiveness in terms of viscoelastic properties depended on the length of the oligopeptide, with the hydrogel being more responsive when functionalized with 10 proline units compared with 5 proline units. Furthermore, the double crosslinked Ca2+–oligoproline–CNF hydrogels promoted the survival of human dermal fibroblasts exposed to high levels of ROS. This study is the first one to provide an insight into the development of ROS-sensitive materials based on CNFs and opens up possibilities for further investigation on the use of these novel materials in chronic wound care.
13.	Grabowski, Alexander, 1993 (författare) VCSEL Equivalent Circuits and Silicon Photonics Integration 2022 Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract The vertical-cavity surface-emitting laser (VCSEL) is a light source of great importance for numerous industrial and consumer products. The main application areas are datacom and sensing. The datacom industry uses GaAs-based VCSELs for optical interconnects, the short-reach fiber optical communication links used to transfer large amounts of data at high rates between units within data centers and supercomputers. In the area of sensing, VCSELs are largely used in consumer products such as smart phones (e.g. face ID and camera auto focus), computer mice, and automobiles (e.g. gesture recognition and LIDAR for autonomous driving). In this work, an advanced physics-based equivalent circuit model for datacom VCSELs has been developed. The model lends itself to co-design and co-optimization with driver and receiver ICs, thereby enabling higher data rate transceivers with bandwidth limited VCSELs and photodiodes. The model also facilitates an understanding of how each physical process within the VCSEL affects the VCSEL static and dynamic performance. It has been applied to study the impact of carrier transport and capture on VCSEL dynamics. The work also includes micro-transfer-printing of GaAs-based single-mode VCSELs on silicon nitride photonic integrated circuits (PICs). Such PICs are increasingly used for e.g. compact and highly functional bio-photonic sensors. Transfer printing of VCSELs enables the much-needed on-PIC integration of power efficient light sources. The bottom-emitting VCSELs are printed above grating couplers on the PIC and optical feedback is used to control the polarization for efficient coupling to the silicon nitride waveguide. Wavelength tuning, as required by the bio-sensing application, is achieved by direct current modulation.
14.	Ottonello Briano, Floria (författare) Mid-infrared photonic devices for on-chip optical gas sensing 2019 Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract Gas detection is crucial in a wide range of fields and applications, such as safety and process control in the industry, atmospheric sciences, and breath diagnostics. Optical gas sensing offers some key advantages, compared to other sensing methods such as electrochemical and semiconductor sensing: high specificity, fast response, and minimal drift.Wavelengths between 3 and 10 μm are of particular interest for gas sensing. This spectral range, called the mid-infrared (mid-IR), is also known as the fingerprint region, because several gas species can be identified by their sharp absorption lines in this region. The most relevant mid-IR-active gases are the trace gases carbon dioxide (CO2), methane (CH4), carbon monoxide (CO), ammonia (NH3), and nitrous oxide (N2O). They are greenhouse gases, contributing to global warming. They are waste products of human activities and widely used in agriculture and industry. Therefore, it is crucial to accurately and extensively monitor them. However, traditional optical gas sensors with a free-space optical path configuration, are too bulky, power-hungry, and expensive to be widely adopted.This thesis presents mid-IR integrated photonic devices that enable the on-chip integration of optical gas sensors, with a focus on CO2 sensing. The reported technologies address the fundamental sensor functionalities: light-gas interaction, infrared light generation, and infrared light detection. The thesis introduces a novel mid-IR silicon photonic waveguide that allows a light path as long as tens of centimeters to fit in a volume smaller than a few cubic millimeters. Mid-IR CO2 spectroscopy demonstrates the high sensing performance of the waveguide. The thesis also explores the refractive index sensing of CO2 with a mid-IR silicon photonic micro-ring resonator.Furthermore, the thesis proposes platinum nanowires as low-cost infrared light sources and detectors that can be easily integrated on photonic waveguides. Finally, the thesis presents a large-area infrared emitter fabricated by highs-peed wire bonding and integrated in a non-dispersive infrared sensor for the detection of alcohol in breath.The technologies presented in this thesis are suited for cost-effective mass production and large-scale adoption. Miniaturized integrated optical gas sensors have the potential to become the main choice for an increasingly broad range of existing and new applications, such as portable, distributed, and networked environmental monitoring, and high-volume medical and consumer applications.
15.	Rebolledo Salgado, Israel, 1992, et al. (författare) Active Feedback Stabilization of Super-efficient Microcombs 2023 Ingår i: 2023 Conference on Lasers and Electro-Optics Europe & European Quantum Electronics Conference (CLEO/Europe-EQEC). - : Institute of Electrical and Electronics Engineers (IEEE). - 2833-1052. - 9798350345995 Konferensbidrag (refereegranskat)abstract We report the long-term operation of a super-efficient microcomb. We use the soliton power to maintain a fixed pump detuning. The microcomb operates over 25 hours using a thermal control in a packaged module.
16.	Sattari, Amir, 1980-, et al. (författare) INDUSTRIAL NANOPARTICLES HEALTH RISKS AND ADVANTAGES OF A DECENT INDUSTRIAL VENTILATION SYSTEM IN REDUCING THE RELATED RISKS 2012 Ingår i: INDUSTRIAL NANOPARTICLES HEALTH RISKS AND ADVANTAGES OF A DECENT INDUSTRIAL VENTILATION SYSTEM IN REDUCING THE RELATED RISKS. ; , s. -6 Konferensbidrag (refereegranskat)abstract With the fast-growing use of nanoparticles (NPs) in a wide range of production and manufacturing processes, and great health and environmental risks associated to NPs, it is important to treat the industry-produced NPs in a proper way. Ventilation of industrial workplaces lies within the concept of sustainability challenges for the development of nanoproducts. Due to the decreased grain size of material to nano limits and thus the appearance of either new or changed properties, health risk of workers in such environments is critical concerning the complicated and unknown characteristics of nanoparticles. There is great evidence over the past few years that ultrafine particles and especially NPs in the breathing air are strong toxins. Different mitigation measures for air-borne nanoparticles in industrial workplaces are substitution, engineering controls such as ventilation and provision of personal protective equipment. In this paper selection criteria for ventilation systems and different ventilation methods (hood ventilation and global enclosure/room ventilation systems) as engineering controls of nanoparticles within industrial enclosures will be reviewed. Novel methods for improvement of ventilation efficiency in general and industrial work places with an eye on ventilation of nanoparticles will be presented.
17.	Santos Andrade, Tatiana, 1991, et al. (författare) Low platinum fuel cell as enabler for the hydrogen fuel cell vehicle 2024 Ingår i: Journal of Power Sources. - 0378-7753. ; 598 Tidskriftsartikel (refereegranskat)abstract In this work, the design and modeling of a fuel cell vehicle using low-loading platinum catalysts were investigated. Data from single fuel cells with low Pt-loading cathode catalysts were scaled up to fuel cell stacks and systems, implemented in a vehicle, and then compared to a commercial fuel cell vehicle. The low-loading Pt systems have shown lower efficiency at high loads compared to the commercial systems suggesting less stable materials. However, the analysis showed that the vehicle comprising low-loading Pt catalysts achieves similar or higher efficiency compared to the commercial fuel cell vehicle when being scaled up for the same number of cells. When the systems were scaled up for the same maximum power as the commercial fuel cell vehicle, all the low-loading Pt fuel cell systems showed higher efficiencies. In this case, more cells are needed, but still, the amount of Pt is significantly reduced compared to the commercial one. The high-efficiency results can be associated with the vehicle's power range operation that meets the region where the low-loading Pt fuel cells have high performance. The results suggested a positive direction towards the reduction of Pt in commercial fuel cell vehicles supporting a cost-competitive clean energy transition based on hydrogen.
18.	Kustanovich, Kiryl, 1987 (författare) Integration of Surface Acoustic Wave and Microfluidic Technologies for Liquid-Phase Sensing Applications 2019 Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract This thesis discusses a new concept for construction of a novel SAW in-liquid sensor employing surface acoustic wave resonance (SAR) in a one-port configuration. In this concept, the reflective gratings of a one-port SAW resonator are employed as mass loading-sensing elements, while the SAW transducer is protected from the measurement environment, reducing power losses significantly. Microfluidic technologies have developed during the last decades into versatile platforms for miniaturized analytical devices. The devices are small, low cost, capable of multi-step automation resulting in fast turnaround, and allow reducing the amount of reagent and sample consumption, while maintaining a precise control over the environment. In this context, small, cheap and efficient sensors capable of in-liquid operation within microfluidic devices are in a great demand. The introduction of acoustic wave technology onto lab-on-a-chip platforms provides sensing capability that meets these criteria, and allows for an extended set of functions to be implemented, e.g., fast fluidic actuation, contact-free particle manipulation, sorting, and others. A resonant SAW sensor topology embedded in a polydimethylsiloxane (PDMS) microfluidic analyte delivery system was fabricated and characterized. Designs with the best performance were identified, and initial measurements in a liquid environment are discussed. In comparison to a delay-line topology, the proposed one-port resonant configuration features improved sensitivity, while offering better electrical performance and smaller size, which allows for wafer-scale fabrication and facilitates integration. Following optimization, sensing performance was evaluated by means of different assays, and multiparametric sensing was demonstrated by sharing of sensor components for simultaneous SAR sensing and electrochemical impedance spectroscopy in different frequency bands. This technological advancement may open pathways to new analytical instrumentation. The small sensor footprint, low energy consumption, and simple two-wire readout facilitate the integration in hand-held “lab on a chip” assay devices, the construction of sensing arrays for parallel sample processing, and the implementation of wireless data transfer schemes.
19.	Apaydin, Dogukan, 1991, et al. (författare) Optically Pumped UVC Photonic Crystal Surface-Emitting Laser 2023 Konferensbidrag (övrigt vetenskapligt/konstnärligt)abstract Photonic crystal surface-emitting lasers (PCSELs) are a new type of semiconductor lasers that offer a high optical output power while maintaining single-mode operation and a low divergence angle. Such devices rely upon the in-plane optical feedback from a two-dimensional photonic crystal and feature out-of-plane emission of the modes with zero group velocity at the photonic band edges by diffraction. Since the demonstration of the first PCSEL [1], the concept has been implemented in standard semiconductor materials with the demonstration of highperforming infrared and blue-emitting lasers [2, 3]. Extending the laser operation to shorter emission wavelengths would be a major breakthrough as such lasers would be of high interest for disinfection, material processing, curing, and medical treatments.
20.	Koptyug, Andrey, 1956-, et al. (författare) Electron Beam Melting: from Shape Freedom to Materials Properties Control at Macro- and Microscale 2021 Ingår i: Proceedings of the THERMEC 2020, Graz, Austria. - : Trans Tech Publications. ; , s. 755-759 Konferensbidrag (refereegranskat)abstract Electron beam melting (EBM) is one of the constantly developing powder bed fusion (PBF) additive manufacturing technologies (AM) offering advanced control over the manufacturing process. Freedom of component shapes is one of the AM competitive advantages already used at industrial and semi- industrial scale. Development of the additive manufacturing today is targeting both widening of the available materials classes, and introducing new enabling modalities. Present research is related to the new possibilities in tailoring different material properties within additively manufactured components effectively adding “fourth dimension to the 3D-printing”. Specific examples are given in relation to the electron beam melting, but majority of the conclusions are valid for the laser-based PBF techniques as well. Through manipulating beam energy deposition it is possible to tailor quite different material properties selectively within each manufactured component, including effective material density as well as thermal, mechanical, electrical and acoustic properties. It is also possible to acquire by choice both metal-metal composite and completely alloyed material, when blends of precursor powder are used together with the beam energy manipulation.
21.	Fu, Qilin, 1986- (författare) High dynamic stiffness nano-structured composites for vibration control : A Study of applications in joint interfaces and machining systems 2015 Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract Vibration control requires high dynamic stiffness in mechanical structures for a reliable performance under extreme conditions. Dynamic stiffness composes the parameters of stiffness (K) and damping (η) that are usually in a trade-off relationship. This thesis study aims to break the trade-off relationship.After identifying the underlying mechanism of damping in composite materials and joint interfaces, this thesis studies the deposition technique and physical characteristics of nano-structured HDS (high dynamic stiffness) composite thick-layer coatings. The HDS composite were created by enlarging the internal grain boundary surface area through reduced grain size in nano scale (≤ 40 nm). The deposition process utilizes a PECVD (Plasma Enhanced Chemical Vapour Deposition) method combined with the HiPIMS (High Power Impulse Magnetron Sputtering) technology. The HDS composite exhibited significantly higher surface hardness and higher elastic modulus compared to Poly(methyl methacrylate) (PMMA), yet similar damping property. The HDS composites successfully realized vibration control of cutting tools while applied in their clamping interfaces.Compression preload at essential joint interfaces was found to play a major role in stability of cutting processes and a method was provided for characterizing joint interface properties directly on assembled structures. The detailed analysis of a build-up structure showed that the vibrational mode energy is shifted by varying the joint interface’s compression preload. In a build-up structure, the location shift of vibration mode’s strain energy affects the dynamic responses together with the stiffness and damping properties of joint interfaces.The thesis demonstrates that it is possible to achieve high stiffness and high damping simultaneously in materials and structures. Analysis of the vibrational strain energy distribution was found essential for the success of vibration control.
22.	Das, Atanu Kumar, et al. (författare) Developments of nanocomposites in supercapacitor applications 2023 Ingår i: Nanocomposites-Advanced Materials for Energy and Environmental Aspects. - : Elsevier. - 9780323997041 Bokkapitel (övrigt vetenskapligt/konstnärligt)abstract Energy demand is increasing due to the development of modern society. The use of electronic devices including portable ones is increasing gradually. Thus it is influencing the development of supercapacitors for energy storage due to their 10â€“100 times higher energy storage capacity. At the same time, the implication of biobased material is being considered as environmentally friendly. Cellulose is the most abundant natural renewable biomaterial. Nanocellulose obtained from cellulose possesses special mechanical and electrochemical properties that are being applied for the fabrication of supercapacitors, such as their low-cost and high conductivity and their inexpensive and environment-friendly natures. The development strategy and performance are discussed for better understanding. The work undertaken on improving the fabrication of supercapacitors from cellulose-based nanocomposites will also be summarized.
23.	Das, Atanu Kumar, et al. (författare) Nanocomposites in energy storage applications 2023 Ingår i: Nanocomposites-Advanced Materials for Energy and Environmental Aspects. - : Elsevier BV. - 9780323997041 ; , s. 175-187 Bokkapitel (övrigt vetenskapligt/konstnärligt)abstract The development of energy storage devices for the growing energy demand is a prerequisite for modern society. Specific characteristics, i.e., thermal, electrochemical, and mechanical properties, of nanocomposites are essential for their application in energy storage appliances. Biobased nanocomposites are being considered environmentally friendly. Nanocellulose, lignin, and chitosan are obtained from an abundant source of natural renewable materials. Using them in developing batteries and supercapacitors has great potential for a sustainable supply of energy. Nanocellulose and the lignin-based electrode have shown excellent electrochemical properties for application in a battery. Nanocellulose, lignin, and chitosan-based electrode have also exhibited excellent electrochemical properties for their utilization in supercapacitors. In addition, their low-cost, high conductivity, and environment-friendly nature are being considered for the preparation of energy storage devices. In this chapter, the development strategy and performance of batteries and supercapacitors obtained from biobased nanocomposites have been discussed.
24.	Lin, Yen-Ku, et al. (författare) A versatile low-resistance ohmic contact process with ohmic recess and low-temperature annealing for GaN HEMTs 2018 Ingår i: Semiconductor Science and Technology. - : IOP Publishing. - 1361-6641 .- 0268-1242. ; 33:9 Tidskriftsartikel (refereegranskat)abstract Deeply recessed ohmic contacts for GaN-based high electron mobility transistors (HEMTs) are demonstrated. It is shown that low-resistance ohmic contacts can be achieved with recessing beyond the AlGaN Schottky barrier where the ohmic contacts are formed on the sidewall of the recess. This makes the process versatile and relatively insensitive to the exact recess depth. The ohmic contact is based on a gold-free metallization scheme consisting of a Ta/Al/Ta metal stack requiring a low-temperature annealing. Important parameters for this type of ohmic contact process include the metal coverage, slope of the etched sidewall, bottom Ta-layer thickness, as well as annealing temperature and duration. The optimized contact resistance is as low as 0.24 Omega mm after annealing at 575 degrees C. Moreover, this sidewall contact approach was successfully implemented on different epitaxial heterostructures with different AlGaN barrier thickness as well as with and without AlN exclusion layer. All the samples exhibited excellent contact resistances in a wide range of recess depths. The Ta-based, sidewall ohmic contact process is a promising method for forming an ohmic contact on a wide range of GaN HEMT epitaxial designs.
25.	Cantatore, Valentina, 1986, et al. (författare) Towards multifunctional coating in the boron-doped graphene/copper system 2017 Ingår i: Carbon. - : Elsevier BV. - 0008-6223. ; 115, s. 375-379 Tidskriftsartikel (refereegranskat)abstract A route to achieve multi-functional graphene coating is explored. Chemical bonding between copper substrate and coating results if the graphene is a priori boron doped. After pair-wise binding of boron sites to the Cu(111) surface, co-existence of pseudo-gap property in the graphene subsystem and a metallic density of states in the Cu subsystem at the common Fermi energy emerges. Apparently a paradox is that the two subsystems preserve and even recover their individual integrities upon formation of surface chemical bonds. Sensor capabilities are inferred. Employing pyridine as test molecule, conditioned ability of a nucleophile to offer competitive dative bonding, with the sub-strate, for boron sites is demonstrated. It is shown to occur for the case of half coverage and for adsorption to boron atoms originally bound to the on-top site on Cu(111). The ability of complementary boron sites to compensate for loss of binding between on-top site and boron, resulting from said bonding to the incoming nucleophile, is emphasized. Multifunctional substrate-coating system for catalysis as well as enhanced sensitization is inferred.

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