Heat Shrink Research Articles

Mixed particles separation based on a cylindrical microfluidic centrifuge

This paper presents a novel cylindrical centrifuge designed to separate microspheres and cells. The polyvinylidene-fluoride tubes with heat shrink characteristics were used to encapsulate helix microchannels. Numerical simulations were employed to analyze and design the channel helix structure (with five annular loops, 2 mm pitch and 20 mm cylinder diameter). Then, The inertial focusing of microspheres (with diameters of 10, 15 and 20 µm) and the freshwater microalgae (i.e. Haematococcus pluvialis) in the cylindrical centrifuge were studied experimentally. As the particle size increased, the focusing position moved toward the center line of the flow channel, and the focus degree tended to decrease. When the flow rate increased, the focus position barely changed, but the focus degree increased significantly. A quantitative study of the centrifuge efficiency revealed that when the initial concentration was 104 particles ml−1 and the flow rate was at its optimal 1.7 ml min−1, the centrifugal efficiency (CE) values of 10 µm, 15 µm, 20 µm microspheres, and H. pluvialis, were 98.8%, 87.8%, 70.8% and 64.6%, respectively. The CE is inversely proportional to the microsphere size and the initial concentrations. Compared with the other two centrifuges (the cavity-vortex and planar spiral), the cylindrical centrifuge design and manufacturing process have a simplicity that provides low cost, efficient sample handling, and effective separation of microspheres and biological cells.

Variable Shape Tooling for Composite Manufacturing: A Systematic Review

The choice of material, manufacturing process, and molding tool significantly affects the quality, environmental impact, and cost efficiency of composite components. Producing one-piece hollow profiles with smooth inner surfaces and undercuts presents major challenges for conventional mold concepts. There is yet no thorough review of shape-variable mandrels in composite manufacturing to be found in the literature. This paper provides an overview of research on shape memory polymers and other shape-variable materials used in tooling applications for composite manufacturing. This work covers shape memory, heat shrink, and other deformable tooling concepts that enable the production of one-piece Type V pressure vessels, air intake ducts, or curved struts and tubes. A systematic literature review in combination with a state-of-the-art open-source active learning tool ASReview is conducted. Fifteen relevant studies were identified. Research on shape-variable tooling is mainly conducted by three research groups in the USA and the PRC. The tooling is mostly made of unreinforced thermosets, especially styrene-based ones. Thermoplastic resins are less common, and reinforcements limit the usable elongation in the temporary shape. The shape variability is either a shape memory and/or a softening process, which, in all studies, is activated by heating. Release agents are widely used to ease demolding. No ecological or economical assessment of the manufacturing methods was conducted in the reviewed studies. Three fields for further research that could be identified are as follows: (1) thorough ecological end economical assessment of shape-variable mandrels in comparison with conventional tooling; (2) thermoplastic shape memory polymer mandrels; and (3) further investigation of simulation capabilities for shape memory mandrels.

Special at-rich sequence-binding protein 2 and its role in healing of the experimental mandible bone tissue defect filling with a synthetic bone graft material and electrical stimulation impact.

Aim: The purpose of the study was to identify the role of SATB2 in healing of the experimental mandible bone tissue defect filling with a synthetic bone graft material and electrical stimulation impact. Materials and Methods: An experiment was carried out on 48 mature male rats of the WAG population, which were divided into 4 groups. Each group included 12 experimental animals. Group 1 included rats that were modeled with a perforated defect of the lower jaw body. Group 2 included animals that were modeled with a perforated defect similar to group 1. In animals, a microdevice for electrical action was implanted subcutaneously in the neck area on the side of the simulated bone defect. The negative electrode connected to the negative pole of the battery was in contact with the bone defect. The battery and electrode were insulated with plastic heat shrink material. Group 3 included rats that were modeled with a perforated defect similar to previous groups, the cavity of which was filled with synthetic bone graft "Biomin GT" (RAPID, Ukraine). Group 4 included animals that were modeled with a perforated defect similar to groups 1-3, the cavity of which was filled with synthetic bone graft "Biomin GT" (RAPID, Ukraine). The simulation of electrical stimulation was the same as in group 2. The material for the morphological study was a fragment of the body of the lower jaw from the zone of the perforated defect. Immunohistochemical study was performed using rabbit anti-human SATB2 monoclonal antibody. Results: In the regenerate filling the defect in the bone tissue of the lower jaw of rats, there was an increase in SATB2 expression under conditions of electrical stimulation; filling the defect with a synthetic bone graft material; simultaneous filling the defect with a synthetic bone graft material and electrical stimulation. The most pronounced expression of SATB2 was observed under conditions of simultaneous filling the defect with a synthetic bone graft material and electrical stimulation; minimally expressed - in conditions of filling the defect with a synthetic bone graft material; moderately expressed - under conditions of electrical stimulation. In the regenerate, in cases of all treatment methods, SATB2 was expressed by immune cells, fibroblastic differon cells, osteoblasts, and in case of electrical stimulation, also by adipocytes, vascular pericytes and endothelial cells, epidermis. Conclusions: The activation of SATB2 expression identified by the authors is one of the mechanisms for stimulating reparative osteogenesis under the conditions of electrical stimulation; filling the defect with a synthetic bone graft material; simultaneous filling the defect with a synthetic bone graft material and electrical stimulation.

Finger joint aligned flat tube folding structure for robotic glove design

Pneumatic soft actuators have been widely considered the safest actuation technology for use in wearable rehabilitation robots. For soft robotic gloves, researchers commonly put soft extending or bending actuators on dorsal fingers to assist hand flexion. In this research, we propose a novel pre-folded flat tube actuator (PFTA) to assist finger flex into a pre-set bending angle or contact force. The PFTA has three folds, aligned with each of the finger joint. Different from other soft actuators, the PFTA exerts bending torque directly on each finger joint without large actuator deformation. The PFTA made of heat shrink flat tube has a small profile, with low cost, easy fabrication, and high safety. When actuated, the PFTA has the tendency to unfold as well, we call this effect as unfolding flat tube actuation. This effect is characterized by a range of bending angles and input air pressures in which four distinct response regimes were observed. They are defined as shearing, collapsing, creasing, and flattening regimes. Similarly, experimental characterization of PFTAs is also conducted to evaluate the level of joint flexion assistance based on which design guidelines for robotic gloves are recommended. Finally, we build PFTAs on a soft wearable glove and demonstrate their capability in assisting the grasping operations of various object shapes.

Multifilament HTS Cables to Reduce AC Loss: Proof-of-Concept Experiments and Simulation

Reducing AC losses of HTS is essential for AC application since it can lower the constraint on the cryogenic cooling demand. Several studies have reported that the manufacturing of multi-filament HTS cables can reduce AC loss. However, large coupling losses were identified in the existing cables, due to the existence of coupled copper or soldering layers. We report in this paper a novel way to develop multi-filament HTS cables, mainly focusing on suppressing the coupling losses by reducing the contact resistivity within the HTS cables. Heat shrink tubes are used to directly insulate narrow HTS filaments into a cable structure. Sample cables were made with 4 mm and 2 mm wide HTS strips. Both transport losses and total AC losses in a rotational magnetic field were measured to quantify the AC loss reduction for the multi-filament HTS cables. The measurements were used to validate the modelling results, and to predict AC loss reduction for 1 mm wide HTS cable. The results showed loss reduction up to around 90% in the 1mm wide HTS cable compared with 4 mm cable. As a result, the proposed multi-filament HTS cables will have promising applications in reducing AC loss.

Plasmonic gold dogbone nanorattles sniff out trace molecules through surface enhanced Raman scattering.

In this study, a highly sensitive and efficient surface-enhanced Raman spectroscopy (SERS) substrate was developed using Au dogbone nanorattles (Au-DBNRTs) deposited on a 3D wrinkled polymeric heat shrink film. The plasmonic structures of Au-DBNRTs, which possess a solid gold dogbone-shaped core and a thin, porous gold shell, and Au nanorod nanorattles (Au-NRNRTs), which have a rod-shaped core, were synthesized and their SERS performance was evaluated. Au-DBNRTs exhibited better Raman signal enhancement. The substrate was used to detect the pesticide thiabendazole with a limit of detection of up to 10-8 M. The unique optical properties and geometry of the Au-DBNRT nanoparticles, which have portruding corners in the vicinity of the metal shell, along with the shrinkage of the film after heat treatment, led to the creation of a 3D surface morphology, resulting in the generation of plasmonic electromagnetic hot spots. The fabricated substrate achieved an enhancement factor of 2.77 × 1010 for BDT, and the detection limit was 10-13 M. The current work offers a simple, cost-effective, and sensitive SERS substrate design that has great potential for sensing and detecting trace analytes.

MORPHOLOGICAL CHARACTERISTICS OF REPARATIVE OSTEOGENESIS IN THE RATS LOWER JAW UNDER THE CONDITIONS OF USING ELECTRICAL STIMULATION.

Aim: The purpose of the study was to identify the morphological features of reparative osteogenesis in the rats lower jaw under the conditions of using electrical stimulation. Materials and Methods: An experiment was conducted on 24 mature male rats of the WAG population. Two groups were formed. Group 1 included 12 rats that were modeled with a perforated defect of the lower jaw body. Group 2 included 12 animals that were modeled with a perforated defect similar to group 1. In animals, a microdevice for electrical action was implanted subcutaneously in the neck area on the side of the simulated bone defect (a temporary Videx AG 4 battery; a constant sinusoidal electric current of an unchanging nature 1 milliampere, frequency 30 W). The negative electrode connected to the negative pole of the battery was in contact with the bone defect. The battery and electrode were insulated with plastic heat shrink material. Morphological and statistical methods were used. Results: The positive effect of electrical stimulation on reparative osteogenesis was due to a decrease in the severity of hemodynamic disorders, activation of angiogenesis in granulation tissue, which was one of the components of the regenerate that filled the bone defect, matured and turned into connective tissue; stimulation of the proliferative potential of fibroblastic cells and cells with osteoblastic activity in granulation tissue; increasing the proliferative potential of osteoblastic elements of bone tissue bordering the cavity; stimulation of macrophage cells and processes of cleansing the bone cavity from fragments of a blood clot and alteratively changed tissues; formation of clusters of adipocytes in the loci of connective and granulation tissue of the regenerate; the process of metaplasia of connective tissue into bone tissue; an increase of the foci of hematopoiesis in the intertrabecular spaces of lamellar bone tissue. Conclusions: A comprehensive clinical and experimental study conducted by the authors proved that electrical stimulation activates the reparative osteogenesis in the lower jaw, which occurs through direct osteogenesis and does not finish on the 28th day of the experiment.

Tracking, Erosion and Morphological Study of Heat Shrink Anti Tracking Tubes

Components of Medium Voltage (MV) cable network are very much vulnerable under operational stresses and ageing. Heat Shrinkable Anti-Tracking Tube (HSATT), an integral part of the Joints and terminations of the MV cable network system is used to cover and safeguard the power cable joints. In cable system joint and termination are the weakest but the critical part and fail easily under stress. The most threatening source of HSATT failure is electrical tracking. Electrical tracking develops when a conducting path across the HSATT formed under electric stress due to surface discharge. Arcs created from this surface discharge phenomenon burn the HSATT and create carbonized tracks in the long run. This paper reports the electrical tracking performance of three commercially available HSATT samples. Crosslinked polyethylene (XLPE) is the key ingredient for heat shrinkable materials. Electrical tracking using the inclined-plane tracking (IPT) method develops from surface discharge activity followed by erosion under wet and contaminated conditions. So, the material under IPT test faced electrical, environmental and thermal stresses. Among these three HSATT samples two samples failed to withstand these three dimensional stress factors. Dielectric breakdown strength and volume resistance tests were carried out to cross examine the IPT results and the results are identical. The morphology has been studied to understand the failure mechanism of HSATT samples. A morphological model is presented to scrutinize the IPT test failure mechanism and the rate of erosion propagation in the HSATT samples.

Flexible and heat-resistant polyphenylene sulfide ultrafine fiber hybrid separators for high-safety lithium-ion batteries

Separators play a critical role in the safety and electrochemical performance of lithium-ion batteries (LIBs). However, the commercial polyolefin-based separators encounter poor thermal stability and flame retardance, which have aroused severe safety issues. Herein, a flexible and heat-resistant porous separator based on sea-island polyphenylene sulfide (PPS) ultrathin fiber and glass nanofiber (GNF) network is rationally designed and successfully fabricated. This hierarchical network is bound via hot pressing and modification of silane coupling agent (γ-3-glycidoxypropyltrimethoxy silane, γ-GPS), endowing the separator with high flexibility and excellent mechanical performance. Also, this novel composite separator features distinguished thermal stability (without any heat shrink at 250 °C for 30 min) and flame retardant properties, guaranteeing the safety of the battery. Due to the inherent polarity and porous structure, the as-prepared PPS-mGNFs separator achieves a small contact angle (18.2°) of liquid electrolyte (LiPF6) and a high electrolyte uptake (253%), implying much better electrolyte wettability than the commercial polyolefin separator. In addition, the LIB integrated with PPS-mGNFs separator exhibits excellent discharge capacity, C-rate performance and cycling performance. This facile and promising strategy provides a platform for the large-scale fabrication of high-performance and safe LIB separators.

Molecular dynamics study on the effect of external electric field on thermal properties of ammonia/copper nano-refrigerant in a nanochannel equipped with different types of cavities

Optimizing and increasing the efficiency of heat transfer systems was one of the main challenges for engineers and designers in recent years. Therefore, the use of nanoparticles in base fluids is known as a passive method to improve heat transfer and shrink heating and cooling systems. In this research, the heat transfer of copper nanoparticles with ammonia refrigerant in a nanochannel was investigated by molecular dynamics simulation. The results show that, with increasing the electric field frequency from 0.1 1/ps to 0.5 1/ps, the phase change time increases from 2 ns to 3 ns and the thermal conductivity decreases from 0.76 W/m.K to 0.72 W/m.K. Also, the effect of the different cavities (hermetic, spherical, and cube shape) in the nanochannel on the atomic and thermal behavior of the simulated atomic samples is investigated. The results show that the maximum thermal conductivity of the sample with a cubic cavity is 0.80 W/m.K. The particle phase change value and the phase change time of samples with hermitic, spherical, and cube atomic cavities are obtained 65, 66, and 68%, and 2.88, 2.87, and 2.85 ns, respectively.

Influence of Tool Holder Types on Vibration in Rough Milling of AZ91D Magnesium Alloy.

The article presents the results of an analysis of the influence of the technological parameters related to tool holder types on the vibrations occurring during the milling of AZ91D magnesium alloy. Magnesium alloys are very low-density materials and, therefore, are increasingly being considered as replacement materials for the more commonly used aluminium alloys. The tool used in the study was a carbide end mill with TiAlN coating, clamped in three different types of tool holder: ER collet, heat shrink, and Tendo E hydraulic. The milling tests used straight toolpaths at varied cutting speeds and feed per tooth values. Based on the vibration displacement and acceleration signals recorded during the machining tests, the following were analysed: maximum value, amplitude, and root mean square (RMS) value of the vibrations. As part of the study, composite multiscale entropy (CMSE) analysis was also performed, describing the level of disorderliness of the obtained vibration signals. The increase in machining parameters caused an increase in the values characterising the displacement and acceleration of the vibrations. It was noted that multiscale entropy might be an important parameter describing the vibration signal (both displacement and acceleration).

Use of accelerometer technology for individual tracking of activity patterns, metabolic rates and welfare in farmed gilthead sea bream (Sparus aurata) facing a wide range of stressors

The biosensor technology has the potential to revolutionize the aquaculture industry, but the selection of tagging method, operational mode (stand-alone vs. wireless systems) and telemetry technology ultimately depends on life species, life stage and research question. In particular, AEFishBIT is a small and stand-alone device composed of a tri-axial accelerometer, a microprocessor, a battery and a RFID tag that was designed to be externally attached to the operculum. This unique location serves to provide simultaneous measurements of activity patterns (signals of x- and y-axes) and respiratory frequency (z-axis signal) processed by on-board algorithms. The validity of measurements was initially proved in exercised fish in a swim tunnel respirometer, and its use as a reliable tool for the individual monitoring of whole-organism traits in free-swimming gilthead sea bream was tested herein in fish facing a wide range of biotic and abiotic stressors. The impact of the tagging method, based on the use of monel piercing fish tags with a flexible heat shrink polyethylene ring, was also evaluated and no signs of growth impairment, operculum damage or gill lamellae haemorrhage were found 10 days post-tagging. The autonomy of the device was 6 h of continuous recording with re-programmable lag times and recording schedules of 2 min windows at regular intervals along the experimental period (2–8 days). Such procedure underlined a negative linear correlation between fasting weight loss and operculum breaths, becoming respiratory frequency a reliable indicator of basal metabolic rates. Biosensing signals also highlighted the more continuous physical activity and increased respiratory rates of young fish when comparisons were made between one- and three-year old fish. Also, AEFishBIT measurements evidenced a generalized increase of respiratory frequency during severe hypoxia (2–3 ppm), but the individuals classified as proactive fish also shared an increased physical activity for supporting escape reactions in a milieu with low oxygen availability. Likewise, we also observed an overall increase of physical activity with the decrease of tank space availability, which can contribute to establish stricter criteria of welfare in farmed fish. Finally, the reduction of respiratory frequency was a consistent diagnostic marker of the progression of parasitic enteritis in experimentally infected fish with the myxozoan Enteromyxum leei. Altogether, this work constitutes the proof of concept of the use of biosensor technology as a reliable tool for an individual whole-organism behavioural profiling of farmed fish at laboratory scale, contributing to improve animal welfare and productivity of aquaculture industry.

Design & analysis of multiple operational tool holder with considering the plain drilling & boring operation under maximum torque conditions

Abstract The quality with computer features is greatly influenced by the movement of machine resulting from process of cutting. Most publications ignore the influence of the person in charge of the tools; this paper considers the dynamic performance of the entire cutting system consisting of a spindle, tool holder, tool and tools. Therefore the vibration performance research is performed to describe the hot and efficient state of the competitive equipment storage technology, namely heatshrink (HS) and hydraulic (HE) expansion. It is shown that HE has higher levels of HS. Therefore, HE has shown good features, 10% higher productivity and up to 300% accessibility of tools. High quality during high performance cutting, good gravity quality of the whole system, built with functionality, tool, tool holder, cracks and machine structure are essential. Available ways to improve the performance of machine tools focus solely on the reduction of directing spindles and machine tool properties, ignoring the influence of the person in charge of the tools, considers different technologies for handling tools, focusing on their influence on the production and life of the tool. Due to the simple limitations of the parameters for making the machine structure model, most of the simulation models available ignore the technical impact of the tool contrast. However, due to the technical differences between the many techniques of assembling the tool, a major impact on the operation of the process machine should be considered. This will lead to different vibration symptoms, which directly affect the quality of operation, as well as the production of digestive processes and the health of the tool. In this the analysis of Tool head for torsional load & Analysis of Tool Holder under the action of axial load is carried out.

A Non-Enzymatic Electrochemical Sensor Using a Wrinkled Gold Film on Shrink Polymer

A non-enzymatic electrochemical uric acid (UA) sensor based on heat-shrinkable polymer was fabricated via a simple and low-cost method without any complex electrode modification for the first time. We sputtered a gold electrode on the heat-shrinkable polymer with shadow masks, taking advantage of the heat shrinkage properties of the polymer to obtain a novel wrinkled gold electrode surface, then detected the UA concentration in aqueous conditions by square wave voltammetry. The performance of the shrink sensor, which was specific to the sensitivity and linearity, improved greatly compared with those non-shrinking ones. The accuracy and long-term stability of tests were also carried out, indicating a more accurate and stable sensor was achieved. Notably, a selectivity enhancement towards glucose interferent was experimentally observed. The selectivity coefficient decreased considerably after the heat shrink process, from −1.28 to −2.6. A new theoretical proposal related to reaction rate suppression was discussed, employing electrostatic shield effect between the wrinkled gold surface and biomolecules with different electrochemical reaction nature. It is a very simple but effective way to monitor UA concentration and the possible reaction control functions of the wrinkled surface can be rationally projected to tailor the electrode properties.

Magnetohydrodynamic nonlinear mixed convection flow of reactive tangent hyperbolic nano fluid passing a nonlinear stretchable surface

The intent of this paper is to unravel the transport of a nonlinear mixed convection tangent hyperbolic nanofluid along a nonlinear stretchable sheet in the neighbourhood of a stagnation point. The impacts of magnetohydrodynamic, thermophoresis, Brownian motion and activation energy together with non-uniform heat source associated with varying thermal conductivity are scrutinized. The outlining transport equations are mutated into a system of nondimensional ordinary differential equations by the use of similarity transformations and then tackled with the Runge–Kutta Fehlberg coupling shooting method. The impact of all essential parameters in respect of the dimensionless quantities are graphically exhibited and deliberated. The significant consequences of the investigation are that increment in the Darcy with magnetic term declines the flow velocity while that uplift the fluid temperature. The skin friction factor triggers a considerable increase with the power-law exponent and magnetic field parameters. The intensity of heat and mass transfer shrink with hike in the values of the thermophoresis parameter. The vetting of the numerical solution is done with earlier related studies in the limiting position and presented in tabular form showing perfect correlation.

Comparison of apparatus and methods for tactile marking of polymeric films with Braille alphabet

This article analyzes contact and non-contact methods for local heat treatment of heat shrink films in tactile marking devices. The characteristics of polymeric film heating processes under heat transfer from metal stamps and laser emitters were investigated. The article contains diagrams obtained by differential scanning calorimetry of polymeric heat shrink film exposed to thermal effect of different tactile marking devices. The article also describes stereometry of Braille elements obtained by using a metal stamp and a laser emitter.

Heat-shrinking DNA nanoparticles for in vivo gene delivery

The particle size of a PEG-peptide DNA nanoparticle is a key determinant of biodistribution following i.v. dosing. DNA nanoparticles of <100 nm in diameter are sufficiently small to cross through fenestrated endothelial cells to target hepatocytes in the liver. In addition, DNA nanoparticles must be close to charge-neutral to avoid recognition and binding to scavenger receptors found on Kupffer cells and endothelial cells in the liver. In the present study, we demonstrate an approach to heat shrink DNA nanoparticles to reduce their size to <100 nm to target hepatocytes. An optimized protocol heated plasmid DNA at 100 °C for 10 min resulting in partial denaturation. The immediate addition of a polyacridine PEG-peptide followed by cooling to room temperature resulted in heat-shrunken DNA nanoparticles that were ~70 nm in diameter compared with 170 nm when heating was omitted. Heat shrinking resulted in the conversion of supercoiled DNA into open circular to remove strain during compaction. Heat-shrunken DNA nanoparticles were stable to freeze-drying and reconstitution in saline. Hydrodynamic dosing established that 70 nm heat-shrunken DNA nanoparticles efficiently expressed luciferase in mouse liver. Biodistribution studies revealed that 70 nm DNA nanoparticles are rapidly and transiently taken up by liver whereas 170 nm DNA nanoparticles avoid liver uptake due to their larger size. The results provide a new approach to decrease the size of polyacridine PEG-peptide DNA nanoparticles to allow penetration of the fenestrated endothelium of the liver for the purpose of transfecting hepatocytes in vivo.

Surface Hydrophobicity in Medium Voltage Terminations

The surface hydrophobicity in medium voltage terminations is studied in this paper to see if the performance of aged heat shrink terminations could be improved. Terminations which are used inside of unheated outdoor enclosures can often be subjected to leakage currents and surface discharges along the insulating surface if the environmental conditions inside the enclosure become harsh. The discharge phenomena on the insulating surface is generally not critical but continuous electrical activity on the surface could eventually lead to a flashover or breakdown as the materials age. The effect of surface hydrophobicity was studied by comparing the performance of heat shrink terminations over a longer time in operation. Improvements were done to aged heat shrink indoor terminations which already had signs of discharge occurrence on the termination surfaces. The results indicate that the performance of these aged terminations improved simply by increasing the surface hydrophobicity of the original installation. The improvement can be done by applying a silicone coating on the termination surface. This solution offers a convenient method for improving the performance of aged heat shrink terminations used in unheated outdoor enclosures.

Time domain dielectric response of field grading sleeves subjected to high humidity and temperatures

It is experienced that MV XLPE cable links including heat shrink cable joints can have a high electrical conductivity compared to the XLPE cable insulation. The field grading sleeve included in the joint design is proposed to be responsible for the reduced insulation resistance and is therefore studied in this paper. New field grading sleeves are aged in the laboratory at temperatures up to 150 °C in both dry and humid conditions. The degree of ageing is determined by DSC measurements, the mechanical properties are determined by tensile strength testing, and the electric properties are characterized by time domain dielectric response measurements. The results show that after only a few days above the melting point of 104 °C the tensile strength of the material is strongly reduced. The electrical conductivity is strongly dependent on the degree of thermal ageing of the sleeve material but also the water content. The combination of significant thermal degradation and a high water content results in particularly high conductivity values. It is shown that the increase of the conductivity after ageing at 150 °C for 15 days is five orders of magnitude for wetted field grading sleeves measured at 30 °C.

Conductive Electrochemically Active Lubricant‐Infused Nanostructured Surfaces Attenuate Coagulation and Enable Friction‐Less Droplet Manipulation

AbstractMicro/nanostructured materials and lubricant‐infused surfaces, both inspired from structures found in nature, are ideally suited for developing self‐cleaning and high surface area transducers for biosensing. These two classes of bio‐inspired technologies are integrated to develop lubricant‐infused electrodes designed to reduce biofouling. Chemical vapor deposition is used to create self‐assembled monolayers of fluorosilane on gold‐modified prestrained polystyrene substrates. After heat shrinking of the substrate, a lubricant is applied to produce a lubricant‐infused nanostructured gold wrinkled surface with hydrophobic properties. These electrically conductive surfaces demonstrate high water contact (≈150°) and low sliding angles (&lt;5°). Moreover, combining these surfaces with passive magnetic actuators enables the actuation of super‐paramagnetic microdroplets in frictionless and open channel conditions without needing full droplet submersion in an immiscible fluid. The fabricated nanostructured surfaces resist protein adhesion in a human plasma coagulation assay and significantly prolong clotting times and retain electrical conductivity, which is essential for electrical sensing applications. The developed hybrid interfaces are expected to have a wide range of applications in biosensing and biological sample preparation involving complex clinical and environmental samples.