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At least 1,045 records · Page 58

Acoustic diagnostic system and method for superconducting devices operating in gas or liquid

A novel system and method for detecting a quench of a superconducting conductor and detecting abnormal behavior of a superconducting conductor using acoustic sensor technology in the coolant of a superconducting cable and/or magnet is disclosed. This system and method is not only limited to use for superconductors, but also may be used for any device disposed in liquid and gas. Acoustic sensors are installed along a coolant space of a superconducting conductor and monitor coolant conditions. By monitoring acoustic changes, temperature changes or coolant flow disruption can be detected very quickly by an acoustic sensor array. By disposition of the acoustic sensor array in a coolant flow channel, the acoustic sensor system can quickly detect a local condition, such as the thermal status (temperature) of a superconducting cable and magnet with precise spatial resolution.

75 CONDENSED MATTER PHYSICS, SUPERCONDUCTIVITY AND↗

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↗

Universal liquid sample device and process for high resolution transmission electron microscope imaging and multimodal analyses of liquid sample materials

Liquid sample imaging devices and processes are disclosed for high resolution TEM imaging and multimodal analyses of liquid sample materials in situ under high vacuum that are compatible with standard type TEM chip membranes and TEM sample holders allowing TEM liquid sample imaging to be performed wherever a TEM instrument is accessible and at a substantially reduced cost compared to prior art systems and approaches.

36 MATERIALS SCIENCE↗

Joint Channel Equalization and Symbol Detection for IoT Devices in Severe Multipath Channels

Internet of Things (IoT) devices often transmit very short message blocks without strong error correction coding or pilots for channel equalization. When the transmitted signals encounter a severe multipath channel, the receiver is often unable to equalize the resulting inter-symbol interference (ISI) via traditional methods, leading to a high retransmission rate. This paper proposes a joint channel equalization and symbol detection scheme for this scenario by utilizing the preamble sequence as a training pilot for equalization and the relatively weak cyclic redundancy check (CRC) 8-Dallas code for error correction. By assuming a sparse channel impulse response, the proposed joint channel equalization and symbol detection scheme formulates an l1 norm constrained optimization problem and solves it by a saddle-point algorithm. The proposed algorithm is applied to a set of real-world underwater animal tracking IoT data, and the results show improvement of correct message detection rate from 21:5% to 41:6%.

Jing, Shusen↗

Method and device for using an organic underlayer to enable crystallization of disordered organic thin films

Measurements on organic single crystals reveal remarkable optical and electrical characteristics compared to disordered films but practical device applications require uniform, pinhole-free films. Disclosed herein is a process to reliably convert as-deposited amorphous thin films to ones that are highly crystalline, with grains on the order of hundreds of microns. The disclosed method results in films that are pinhole-free and that possess grains that individually are single crystal domains.

36 MATERIALS SCIENCE↗

CdSexTe1-x /CdTe Devices With Reduced Interface Recombination Through Novel Back Contacts and Doping Strategies

In order to study rear interface recombination in CdSexTe1-x/CdTe solar cells, several back contact structures were fabricated using combinations of tellurium, alumina, amorphous silicon, and indium tin oxide. Film side Time-Resolved Photoluminescence measurements were taken to measure carrier lifetimes and interface recombination at the back interface. We show increasingly improved interface passivation through the subsequent use of alumina, amorphous silicon, and ITO. Additionally, we provide evidence that an arsenic-doped absorber forms a better interface with numerous back contact structures. Reductions in the back interface recombination velocity are shown to correlate with improvements in device external radiative efficiency.

13 HYDRO ENERGY↗

Zinc-iodine secondary energy storage methods, devices, and electrolytes

Disclosed are cathodes having electron-conductive high-surface-area materials, aqueous non-halide-containing electrolytes, secondary zinc-iodine energy storage devices using the same, and methods for assembling the same. The disclosed high-surface-area materials and the aqueous non-halide-containing electrolyte solutions can contribute together to the confinement of the active iodine species in the cathode and to the minimization of shuttle effects and self-discharging. The non-halide-containing electrolyte salts can facilitate preferential adsorption of the iodine species to the cathode material rather than dissolution in the aqueous electrolyte solution, thereby contributing to the confinement of the active iodine species.

25 ENERGY STORAGE↗

Mesoporous nanocrystalline film architecture for capacitive storage devices

A mesoporous, nanocrystalline, metal oxide construct particularly suited for capacitive energy storage that has an architecture with short diffusion path lengths and large surface areas and a method for production are provided. Energy density is substantially increased without compromising the capacitive charge storage kinetics and electrode demonstrates long term cycling stability. Charge storage devices with electrodes using the construct can use three different charge storage mechanisms immersed in an electrolyte: (1) cations can be stored in a thin double layer at the electrode/electrolyte interface (non-faradaic mechanism); (2) cations can interact with the bulk of an electroactive material which then undergoes a redox reaction or phase change, as in conventional batteries (faradaic mechanism); or (3) cations can electrochemically adsorb onto the surface of a material through charge transfer processes (faradaic mechanism).

25 ENERGY STORAGE↗

Thin film CZTSSe photovoltaic device

A method for forming a back contact on an absorber layer in a photovoltaic device includes forming a two dimensional material on a first substrate. An absorber layer including Cu—Zn—Sn—S(Se) (CZTSSe) is grown over the first substrate on the two dimensional material. A buffer layer is grown on the absorber layer on a side opposite the two dimensional material. The absorber layer is exfoliated from the two dimensional material to remove the first substrate from a backside of the absorber layer opposite the buffer layer. A back contact is deposited on the absorber layer.

14 SOLAR ENERGY↗

Highly reliable stacked white organic light emitting device

An organic light emitting device (OLED) is provided that includes a cathode and an anode; a blue emitting layer; and at least two hybrid red/green emitting layers. One of the at least two hybrid red/green emitting layers is a cathode side, red/green emitting layer that is disposed between the cathode and the blue emitting layer. The second of the at least two hybrid red/green emitting layers is an anode side, red/green emitting layer that is disposed between the blue emitting layer and the anode. The OLED emits white light.

42 ENGINEERING↗

Alloy identification device

An electrochemical metal alloy identification device employing electrolytes to measure and identify different potentials of alloys is presented. This includes physical structure, disposables, electrical systems, control circuitry, and algorithms to identify alloys.

36 MATERIALS SCIENCE↗

Photovoltaic devices with encapsulating barrier film

Encapsulated device including a photovoltaic cell and a composite film overlaying at least a portion of the photovoltaic cell, the composite film further including a substrate, a base (co)polymer layer on a major surface of the substrate, an oxide layer on the base (co)polymer layer, and a protective (co)polymer layer derived from a silane precursor compound on the oxide layer.

14 SOLAR ENERGY↗

Microscopy imaging device with advanced imaging properties

Systems, methods and devices are implemented for microscope imaging solutions. One embodiment of the present disclosure is directed toward an epifluorescence microscope. The microscope includes an image capture circuit including an array of optical sensor. An optical arrangement is configured to direct excitation light of less than about 1 mW to a target object in a field of view of that is at least 0.5 mm 2 and to direct epi-fluorescence emission caused by the excitation light to the array of optical sensors. The optical arrangement and array of optical sensors are each sufficiently close to the target object to provide at least 2.5 μm resolution for an image of the field of view.

Ghosh, Kunal↗

Device and method for cache utilization aware data compression

A processing device is provided which includes memory and at least one processor. The memory includes main memory and cache memory in communication with the main memory via a link. The at least one processor is configured to receive a request for a cache line and read the cache line from main memory. The at least one processor is also configured to compress the cache line according to a compression algorithm and, when the compressed cache line includes at least one byte predicted not to be accessed, drop the at least one byte from the compressed cache line based on whether the compression algorithm is determined to successfully compress the cache line according to a compression parameter.

Das, Shomit N.↗

Energy-harvesting chromogenic devices

The present disclosure relates to devices that include a perovskite, where, when a first condition is met, at least a portion of the perovskite is in a first phase that substantially transmits light, when a second condition is met, at least a portion of the perovskite is in a second phase that substantially absorbs light, and the perovskite is reversibly switchable between the first phase and the second phase by reversibly switching between the first condition and the second condition.

Wheeler, Lance Michael↗