252 research outputs found

    Remote Resonant-Circuit Analyte Sensing Apparatus with Sensing Structure and Associated Method of Sensing

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    A resonant sensing apparatus for operative arrangement within a test environment to sense an analyte. A sensing structure is included having an antenna in electrical communication with a resonant circuit and a structural element made of a material that selectively responds to the analyte. This sensing structure will resonate at a particular characteristic resonant frequency in the presence of an applied interrogation electromagnetic field and the analyte upon the occurrence of the selective response. A receiver is used for remotely identifying a value for the characteristic resonant frequency by measuring a plurality of values for electromagnetic emission intensity of the sensing structure taken over an operating range of frequencies. A length of a conductive segment of any component of the resonant circuit may also function as the antenna. A method of sensing an analyte with the sensing structure includes arranging the sensing structure within a test environment and applying an interrogation electromagnetic field causing the sensing structure to resonate. A pre-correlation made between a series of resonant frequency values taken for the sensing structure and a corresponding series of analyte sensing values can be used for the sensing

    Apparatus and Method for Dispersing Nano-Elements to Assemble Device

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    An apparatus for dispersing a first plurality of conductive elongated nano-elements distributed within a carrier-fluid to assemble a conductive device made of a first charge-receptive area of a support surface to which at least one nano-element has attached, including: a nozzle through which the elongated nano-elements are directed such that the nano-elements pass through an electromagnetic field for imparting a preselected charge thereto, and toward at least the first charge-receptive area. The charge-receptive area is given a charge such that it attracts a first end-portion of one of the nano-elements. Also, a method of assembling a conductive device. Steps include: applying a first charge to the first charge-receptive area to attract a first end-portion of at least one nano-element; and dispersing from a nozzle, the plurality of elongated nano-elements distributed within a carrier-fluid initially contained in a reservoir, such that the nano-elements pass through an electromagnetic field for imparting a preselected charge thereto and toward the first charge-receptive area

    Remote magneto-elastic analyte, viscosity and temperature sensing apparatus and associated methods of sensing

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    An analyte, viscosity, or temperature sensing apparatus for operative arrangement within a time-varying magnetic field, including a sensor with an outer surface that is chemically, frictionally, or thermally responsive and adhered to a base magnetostrictive element, and a receiver to measure a first and second value for magneto-elastic emission intensity of the sensor taken at, respectively, a first and second interrogation frequency. A change in mass or a change in material stiffness of the sensor due to the responsiveness, the viscosity and mass density of a fluid therearound, or the temperature, can be identified. The receiver, alternatively, measures a plurality of successive values for magneto-elastic emission intensity of the sensor taken over an operating range of successive interrogation frequencies to identify a value for the sensor's magneto-elastic resonant frequency (a fundamental frequency or harmonic thereof). Several sensors in an ordered array will provide a package of information

    Temperature, Stress, and Corrosive Sensing Apparatus Utilizing Harmonic Response of Magnetically Soft Sensor Element (s)

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    A temperature sensing apparatus including a sensor element made of a magnetically soft material operatively arranged within a first and second time-varying interrogation magnetic field, the first time-varying magnetic field being generated at a frequency higher than that for the second magnetic field. A receiver, remote from the sensor element, is engaged to measure intensity of electromagnetic emissions from the sensor element to identify a relative maximum amplitude value for each of a plurality of higher-order harmonic frequency amplitudes so measured. A unit then determines a value for temperature (or other parameter of interst) using the relative maximum harmonic amplitude values identified. In other aspects of the invention, the focus is on an apparatus and technique for determining a value for of stress condition of a solid analyte and for determining a value for corrosion, using the relative maximum harmonic amplitude values identified. A magnetically hard element supporting a biasing field adjacent the magnetically soft sensor element can be included

    Electrically-Small Low Q Radiator Structure and Method of Producing EM Waves Therewith

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    An electrically small radiator structure for radiating electromagnetic waves having an electrical size, k*a, with a value less than π/2 and above π/20,000 and configured to have at least a first and second magnetic, or electric, dipole element. Dipole elements are preferably oriented such that a source-associated standing energy value for the structure, or Wds(tR), is low, Radiative Q value preferably less than ⅓(k*a)3; and each of the elements, whether paired with respective electric dipole elements, is in electrical communication through a feed circuit to at least one power source. Further, a first dipole pair (or element) oriented orthogonally with respect to a second pair (or element) are in voltage phase-quadrature; the structure is operational at a frequency below 5 GHz; and dipole moments oriented such that the following is generally satisfied: a divergence of the Poynting vector of the pairs with respect to retarded time, namely ∇|t R ·N, has a value less than 1.0. Also, a method of producing electromagnetic waves using an electrically small radiator structure, including configuring the structure to have at least a first and second pair of dipole moments and an electrical size, k*a, with a value less than π/2 and above π/20,000; and powering a first feed area of the first pair and a second feed area of the second pair with at least one source operating at a frequency to radiate the waves

    Magnetoelastic sensing apparatus and method for remote pressure query of an environment

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    A pressure sensing apparatus for operative arrangement within an environment, having: a sensor comprising a hermetically-sealed receptacle, at least one side of which has an flexible membrane to which a magnetically hard element is attached. Enclosed within the receptacle is a magnetostrictive element that vibrates in response to a time-varying magnetic field. Also included is a receiver to measure a plurality of successive values for magneto-elastic emission intensity of the sensor taken over an operating range of successive interrogation frequencies to identify a resonant frequency value for the sensor. Additional features include: (a) the magnetically hard element may be adhered to an inner or outer side of, or embedded within, the membrane; (b) the magnetostrictive element can include one or more of a variety of different pre-formed, hardened regions; (c) the magneto-elastic emission may be a primarily acoustic or electromagnetic emission; and (d) in the event the time-varying magnetic field is emitted as a single pulse or series of pulses, the receiver unit can detect a transitory time-response of the emission intensity of each pulse (detected after a threshold amplitude value for the transitory time-response is observed). A Fourier transform of the time-response can yield results in the frequency domain. Also, an associated method of sensing pressure of an environment is included that uses a sensor having a magnetostrictive element to identify a magneto-elastic resonant frequency value therefore. Using the magneto-elastic resonant frequency value identified, a value for the pressure of the environment can be identified

    Magnetoelastic sensor for characterizing properties of thin-film/coatings

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    An apparatus for determining elasticity characteristics of a thin-film layer. The apparatus comprises a sensor element having a base magnetostrictive element at least one surface of which is at least partially coated with the thin-film layer. The thin-film layer may be of a variety of materials (having a synthetic and/or bio-component) in a state or form capable of being deposited, manually or otherwise, on the base element surface, such as by way of eye-dropper, melting, dripping, brushing, sputtering, spraying, etching, evaporation, dip-coating, laminating, etc. Among suitable thin-film layers for the sensor element of the invention are fluent bio-substances, thin-film deposits used in manufacturing processes, polymeric coatings, paint, an adhesive, and so on. A receiver, preferably remotely located, is used to measure a plurality of values for magneto-elastic emission intensity of the sensor element in either characterization: (a) the measure of the plurality of values is used to identify a magneto-elastic resonant frequency value for the sensor element; and (b) the measure of the plurality of successive values is done at a preselected magneto-elastic frequency

    Self-Organized One-Dimensional TiO

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    We review the use of self-assembled, vertically oriented one-dimensional (1D) titania nanowire and nanotube geometries in several third-generation excitonic solar cell designs including those based upon bulk heterojunction, ordered heterojunction, Förster resonance energy transfer (FRET), and liquid-junction dye-sensitized solar cells (DSSCs)

    Hierarchical Micro/Nano-Porous Acupuncture Needles Offering Enhanced Therapeutic Properties

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    Acupuncture as a therapeutic intervention has been widely used for treatment of many pathophysiological disorders. For achieving improved therapeutic effects, relatively thick acupuncture needles have been frequently used in clinical practice with, in turn, enhanced stimulation intensity. However due to the discomforting nature of the larger-diameter acupuncture needles there is considerable interest in developing advanced acupuncture therapeutical techniques that provide more comfort with improved efficacy. So motivated, we have developed a new class of acupuncture needles, porous acupuncture needles (PANs) with hierarchical micro/nano-scale conical pores upon the surface, fabricated via a simple and well known electrochemical process, with surface area approximately 20 times greater than conventional acupuncture needles. The performance of these high-surface-area PANs is evaluated by monitoring the electrophysiological and behavioral responses from the in vivo stimulation of Shenmen (HT7) points in Wistar rats, showing PANs to be more effective in controlling electrophysiological and behavioral responses than conventional acupuncture needles. Comparative analysis of cocaine induced locomotor activity using PANs and thick acupuncture needles shows enhanced performance of PANs with significantly less pain sensation. Our work offers a unique pathway for achieving a comfortable and improved acupuncture therapeutic effect. © The Author(s) 2016.1
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