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Wang, Joseph

Publications and source records attributed to Wang, Joseph.

At least 19 records

Single-atom materials boosting wearable orthogonal uric acid detection

Abstract Uric acid (UA) is a vital biomarker for the diagnosis and management of various health conditions, including cardiovascular diseases, gout, kidney disorders, metabolic syndrome, and wound healing. Despite significant advances in wearable sensor technology, challenges persist in developing wearable sensors that are capable of maintaining high sensitivity, selectivity, and stability. In this study, we present an epidermal sensing platform enhanced with single-atom materials (SAMs) designed for flexible and orthogonal electrochemical detection of UA. We designed and synthesized an SAM with Fe-N 5 active sites to boost the electrochemical sensing signals, integrating it with laser-engraved graphene (LEG) to fabricate a wearable SAM-based UA patch sensor. This design provides superior UA detection performance compared to sensors based on conventional nanomaterials. In addition, we enhanced the detection accuracy and range by using an orthogonal approach that combines direct oxidation through differential pulse voltammetry (DPV) along with parallel biocatalytic amperometric detection. The resulting SAM-based UA orthogonal sensor patch demonstrated exceptional performance in wearable applications through tests measuring sweat UA levels in subjects before and after consuming a purine-rich diet. Graphical Abstract

Ding, Shichao↗

Hyperelastic binder for printed, stretchable electronics

Disclosed are compositions, devices, systems and fabrication methods for stretchable composite materials and stretchable electronics devices. In some aspects, an elastic composite material for a stretchable electronics device includes a first material having a particular electrical, mechanical or optical property; and a multi-block copolymer configured to form a hyperelastic binder that creates contact between the first material and the multi-block copolymer, in which the elastic composite material is structured to stretch at least 500% in at least one direction of the material and to exhibit the particular electrical, mechanical or optical property imparted from the first material. In some aspects, the stretchable electronics device includes a stretchable battery, biofuel cell, sensor, supercapacitor or other device able to be mounted to skin, clothing or other surface of a user or object.

Wang, Joseph↗

Electrochemical devices comprising compressed gas solvent electrolytes

Disclosed are novel electrolytes, and techniques for making and devices using such electrolytes, which are based on compressed gas solvents. Unlike conventional electrolytes, disclosed electrolytes are based on “compressed gas solvents” mixed with various salts, referred to as “compressed gas electrolytes.” Various embodiments of a compressed gas solvent includes a material that is in a gas phase and has a vapor pressure above an atmospheric pressure at a room temperature. The disclosed compressed gas electrolytes can have wide electrochemical potential windows, high conductivity, low temperature capability and/or high pressure solvent properties.

25 ENERGY STORAGE↗

Hyperelastic binder for printed, stretchable electronics

Disclosed are compositions, devices, systems and fabrication methods for stretchable composite materials and stretchable electronics devices. In some aspects, an elastic composite material for a stretchable electronics device includes a first material having a particular electrical, mechanical or optical property; and a multi-block copolymer configured to form a hyperelastic binder that creates contact between the first material and the multi-block copolymer, in which the elastic composite material is structured to stretch at least 500% in at least one direction of the material and to exhibit the particular electrical, mechanical or optical property imparted from the first material. In some aspects, the stretchable electronics device includes a stretchable battery, biofuel cell, sensor, supercapacitor or other device able to be mounted to skin, clothing or other surface of a user or object.

42 ENGINEERING↗

Microneedle arrays for biosensing and drug delivery

Methods, structures, and systems are disclosed for biosensing and drug delivery techniques. In one aspect, a device for detecting an analyte and/or releasing a biochemical into a biological fluid can include an array of hollowed needles, in which each needle includes a protruded needle structure including an exterior wall forming a hollow interior and an opening at a terminal end of the protruded needle structure that exposes the hollow interior, and a probe inside the exterior wall to interact with one or more chemical or biological substances that come in contact with the probe via the opening to produce a probe sensing signal, and an array of wires that are coupled to probes of the array of hollowed needles, respectively, each wire being electrically conductive to transmit the probe sensing signal produced by a respective probe.

47 OTHER INSTRUMENTATION↗

Highly Stable Battery Pack via Insulated, Reinforced, Buckling-Enabled Interconnect Array

This work describes a flexible and stretchable battery pack configuration that exhibits highly stable performance under large deformation up to 100% biaxial stretching. Using stress-enduring printable inks and serpentine interconnects, the new screen-printing route offers an attractive solution for converting rigid battery units into a flexible, stretchable energy storage device. Coin-cell lithium ion batteries are thus assembled onto the island regions of a screen-printed, buckling-enabled, polymer-reinforced interconnect “island-bridge” array. Most of the strain on the new energy-storage device is thus accommodated by the stress-enduring serpentine structures, and the array is further reinforced by mechanically strong “backbone” layers. Battery pack arrays are assembled and tested under different deformation levels, demonstrating a highly stable performance (<2.5% change) under all test conditions. Additionally, a light emitting diode band powered by the battery pack is tested on-body, showing uninterrupted illumination regardless of any degrees of deformation. Moreover, battery-powered devices that are ultrastable under large deformation can be easily fabricated by incorporating different electronics parts such as sensors or integrated circuits on the same platform. Such ability to apply traditionally rigid, bulky lithium ion batteries onto flexible and stretchable printed surfaces holds considerable promise for diverse wearable applications.

36 MATERIALS SCIENCE↗

Kinetic Alfvén Turbulence: Electron and Ion Heating by Particle-in-cell Simulations

Three-dimensional particle-in-cell simulations of the forward cascade of decaying kinetic Alfvén turbulence have been carried out as an initial-value problem on a collisionless, homogeneous, magnetized, electron–ion plasma model with β{sub e}=β{sub i}=0.50 and m {sub i}/m {sub e} = 100, where subscripts e and i represent electrons and ions, respectively. Initial anisotropic narrowband spectra of relatively long-wavelength modes with approximately gyrotropic distributions in k{sub ⊥} undergo a forward cascade to broadband spectra of magnetic fluctuations at shorter wavelengths. Maximum electron and ion heating rates are computed as functions of the initial fluctuating magnetic field energy density ε{sub o} on the range 0.05<ε{sub o}<0.50. In contrast to dissipation by whistler turbulence, the maximum ion heating rate due to kinetic Alfvén turbulence is substantially greater than the maximum electron heating rate. Furthermore, ion heating as well as electron heating due to kinetic Alfvén turbulence scale approximately with ε {sub o}. Finally, electron heating leads to anisotropies of the type T{sub ∥e}>T{sub ⊥e}, where the parallel and perpendicular symbols refer to directions parallel and perpendicular, respectively, to the background magnetic field, whereas the heated ions remain relatively isotropic. This implies that, for the range of ε {sub o} values considered, the Landau wave–particle resonance is a likely heating mechanism for the electrons and may also contribute to ion heating.

79 ASTRONOMY AND ASTROPHYSICS↗

Microneedle arrays for biosensing and drug delivery

Methods, structures, and systems are disclosed for biosensing and drug delivery techniques. In one aspect, a device for detecting an analyte and/or releasing a biochemical into a biological fluid can include an array of hollowed needles, in which each needle includes a protruded needle structure including an exterior wall forming a hollow interior and an opening at a terminal end of the protruded needle structure that exposes the hollow interior, and a probe inside the exterior wall to interact with one or more chemical or biological substances that come in contact with the probe via the opening to produce a probe sensing signal, and an array of wires that are coupled to probes of the array of hollowed needles, respectively, each wire being electrically conductive to transmit the probe sensing signal produced by a respective probe.

59 BASIC BIOLOGICAL SCIENCES↗

Microneedle arrays for biosensing and drug delivery

Methods, structures, and systems are disclosed for biosensing and drug delivery techniques. In one aspect, a^ device for detecting an analyte and/or releasing a biochemical into a biological fluid can include an array of hollowed needles, in which each needle includes a protruded needle structure including an exterior wall forming a hollow interior and an opening at a terminal end of the protruded needle structure that exposes the hollow interior, and a probe inside the exterior wall to interact with one or more chemical or biological substances that come in contact with the probe via the opening to produce a probe sensing signal, and an array of wires that are coupled to probes of the array of hollowed needles, respectively, each wire being electrically conductive to transmit the probe sensing signal produced by a respective probe.

59 BASIC BIOLOGICAL SCIENCES↗

High-Performance Screen-Printed Thermoelectric Films on Fabrics

Printing techniques could offer a scalable approach to fabricate thermoelectric (TE) devices on flexible substrates for power generation used in wearable devices and personalized thermo-regulation. However, typical printing processes need a large concentration of binder additives, which often render a detrimental effect on electrical transport of the printed TE layers. Here, we report scalable screenprinting of TE layers on flexible fiber glass fabrics, by rationally optimizing the printing inks consisting of TE particles (p-type Bi 0.5 Sb 1.5 Te 3 or n-type Bi 2 Te 2.7 Se 0.3 ), binders, and organic solvents. We identified a suitable binder additive, methyl cellulose, which offers suitable viscosity for printability at a very small concentration (0.45–0.60 wt.%), thus minimizing its negative impact on electrical transport. Following printing, the binders were subsequently burnt off via sintering and hot pressing. We found that the nanoscale defects left behind after the binder burnt off became effective phonon scattering centers, leading to low lattice thermal conductivity in the printed n-type material. With the high electrical conductivity and low thermal conductivity, the screen-printed TE layers showed high room-temperature ZT values of 0.65 and 0.81 for p-type and n-type, respectively.

36 MATERIALS SCIENCE↗

ARPA-E: Redefining the Problem to Fine New Solutions

ARPA-E brings together experts from diverse disciplines and industries to frame new ways of looking at the energy challenge. By viewing the problem through a different lens, ARPA-E brings together new capabilities to develop new technology solutions. The DELTA and MONITOR programs illustrate this novel approach well. In this video, Associate Director of Technology Dr. Patrick McGrath discusses how ARPA-E has reframed the challenge of building efficiency with the DELTA program and methane leaks with the MONITOR program differently in order to yield “out of left field” technologies that can lead to transformational gains. The video features two projects – University of California San Diego’s DELTA project and Rebellion Photonics’ MONITOR project.

29 ENERGY PLANNING, POLICY, AND ECONOMY↗

Merging of Thin- and Thick-Film Fabrication Technologies: Toward Soft Stretchable “Island-Bridge” Devices

Soft stretchable thick–thin-film devices are prepared by merging different fabrication technologies with different functional materials. The new “island–bridge” devices rely on screen-printed thick-film island electrodes, connected by thin-film serpentine interconnects. Furthermore, such a hybrid fabrication process enables to realize high-performance stretchable materials toward a new class of soft electronics with new capabilities that cannot be achieved via individual fabrication routes.

36 MATERIALS SCIENCE↗

Particle-in-cell simulations of electron and ion dissipation by whistler turbulence: variations with electron β

Two ensembles of three-dimensional particle-in-cell (PIC) simulations of the forward cascade of decaying whistler turbulence have been carried out on a model of collisionless, homogeneous, magnetized plasma with parameters similar to those of the solar wind near Earth. Initial, relatively isotropic, narrowband spectra of relatively long wavelength modes cascade to anisotropic, broadband spectra of magnetic fluctuations at shorter wavelengths. Electron and ion dissipation rates are computed as functions of the initial electron beta, β{sub e}, over the range 0.1 ≤ β{sub e} ≤ 5.0, where this quantity is varied by changes in the background magnetic field magnitude B{sub o}. Ensemble One holds the value of the dimensionless initial magnetic fluctuation energy density ϵ{sub o} ≡ Σ{sub k} |δB{sub k}|{sup 2}/B{sub o}{sup 2} constant; Ensemble Two follows solar wind observations, imposing the initial condition ϵ{sub o} = 0.20 β{sub e}. In both ensembles, the maximum dissipation rate of the electrons, Q{sub e}, and the maximum dissipation rate of the ions, Q{sub i}, satisfy Q{sub e} ≫ Q{sub i}. In Ensemble One, both dissipation rates scale approximately as β{sub e}{sup −1}, whereas over 0.1 ≤ β{sub e} ≤ 1.0 in Ensemble Two, Q{sub e} is approximately constant while Q{sub i} scales approximately as β{sub e}{sup 1/2}. These results, when combined with conclusions from earlier PIC simulations, suggest that sufficiently long wavelength and sufficiently large-amplitude magnetosonic-whistler turbulence at sufficiently large β{sub e} may heat ions more rapidly than electrons.

79 ASTRONOMY AND ASTROPHYSICS↗

All-Printed, Stretchable Zn-Ag 2 O Rechargeable Battery via Hyperelastic Binder for Self-Powering Wearable Electronics

While several stretchable batteries utilizing either deterministic or random composite architectures have been described, none have been fabricated using inexpensive printing technologies. In this study, the authors printed a highly stretchable, zinc-silver oxide (Zn-Ag 2 O) battery by incorporating polystyrene-block-polyisoprene-block-polystyrene (SIS) as a hyperelastic binder for custom-made printable inks. The remarkable mechanical properties of the SIS binder lead to an all-printed, stretchable Zn-Ag 2 O rechargeable battery with a ≈2.5 mA h cm -2 reversible capacity density even after multiple iterations of 100% stretching. This battery offers the highest reversible capacity and discharge current density for intrinsically stretchable batteries reported to date. The electrochemical and mechanical properties are characterized under different strain conditions. The new stress-enduring printable inks pave ways for further developing stretchable electronics for the wide range of wearable applications.

25 ENERGY STORAGE↗