Abstract: One or more implementations of the present specification provide an invoice access method and apparatus based on a blockchain, and an electronic device. The method includes: generating first ciphertext data by encrypting plaintext data of the target invoice based on a first key corresponding to an invoice issuer; generating second ciphertext data by encrypting the plaintext data of the target invoice based on a second key corresponding to an invoice receiver; adding the first ciphertext data and an user identifier of the invoice issuer to the blockchain as related to one another; and adding the second ciphertext data and an user identifier of the invoice receiver to the blockchain as related to one another.

Abstract: A hydrogen sensor for detecting/quantitating hydrogen and hydrogen isotopes includes a sampling line and a microplasma generator that excites hydrogen from a gas sample and produces light emission from excited hydrogen. A power supply provides power to the microplasma generator, and a spectrometer generates an emission spectrum from the light emission. A programmable computer is adapted for determining whether or not the gas sample includes hydrogen, and for quantitating the amount of hydrogen and/or hydrogen isotopes are present in the gas sample.

Abstract: A hydrogen sensor for detecting/quantitating hydrogen and hydrogen isotopes includes a sampling line and a microplasma generator that excites hydrogen from a gas sample and produces light emission from excited hydrogen. A power supply provides power to the microplasma generator, and a spectrometer generates an emission spectrum from the light emission. A programmable computer is adapted for determining whether or not the gas sample includes hydrogen, and for quantitating the amount of hydrogen and/or hydrogen isotopes are present in the gas sample.

Abstract: An apparatus and method for monitoring diabetes through breath acetone detection and quantitation employs a microplasma source in combination with a spectrometer. The microplasma source provides sufficient energy to produce excited acetone fragments from the breath gas that emit light. The emitted light is sent to the spectrometer, which generates an emission spectrum that is used to detect and quantify acetone in the breath gas.

Abstract: An apparatus and method for monitoring diabetes through breath acetone detection and quantitation employs a microplasma source in combination with a spectrometer. The microplasma source provides sufficient energy to produce excited acetone fragments from the breath gas that emit light. The emitted light is sent to the spectrometer, which generates an emission spectrum that is used to detect and quantify acetone in the breath gas.

Abstract: An apparatus and method for the detection of oxygen using optical fiber based evanescent light absorption. Methylene blue was immobilized using a sol-gel process on a portion of the exterior surface of an optical fiber for which the cladding has been removed, thereby forming an optical oxygen sensor. When light is directed through the optical fiber, transmitted light intensity varies as a result of changes in the absorption of evanescent light by the methylene blue in response to the oxygen concentration to which the sensor is exposed. The sensor was found to have a linear response to oxygen concentration on a semi-logarithmic scale within the oxygen concentration range between 0.6% and 20.9%, a response time and a recovery time of about 3 s, ant to exhibit good reversibility and repeatability. An increase in temperature from 21° C. to 35° C. does not affect the net absorption of the sensor.

Abstract: An atmospheric cold plasma brush was used to treat the surfaces of polymers. The surface properties of plasma-treated polymers were compared to those of the corresponding untreated polymers by static water contact angle measurements. Surface treatment usually resulted in a decrease in the static water contact angle, indicating that the treatment resulted in a higher surface energy and surface wettability compared to the untreated polymer.

Abstract: An apparatus with a narrow slit chamber generates plasma having non-equilibrium characteristics and a brush-like shape at a temperature near room temperature and at a pressure of about one atmosphere. Plasma gas enters the narrow slit chamber. An external power source provides power to electrodes near the exit that excite the plasma gas and produce a plasma jet having a brush-like shape that exits the chamber. The apparatus operates with low power consumption, and the temperature of the plasma is low. Glow-to-arc transitions are prevented using a ballast resistor and appropriate plasma gases with the narrow slit chamber design. The brush-like shaped plasma extends beyond the exit of the chamber, and possesses the reactive features of low-pressure or non-equilibrium plasmas. The plasma brush apparatus can be used for plasma treatment, plasma cleaning, plasma deposition, plasma sterilization, and plasma decontamination of chemical and biological warfare agents.

Abstract: Provided is a novel system for conducting elemental measurements using cavity ring-down spectroscopy (CRDS). The present invention provides sensitivity thousands of times improved over conventional devices and does so with the advantages of low power, low plasma flow rate, and the ability being sustained with various gases.

Abstract: A handheld/portable detector for chemical vapor monitoring includes a housing and a discharge chamber that is established therein. The plasma discharge has a relatively small volume, e.g., in the micro-liter range. A first electrode and a second electrode are disposed within the discharge chamber and a discharge gap is established therebetween. A sample gas tube is in fluid communication with the discharge chamber and provides a sample gas to the discharge chamber. Also, a plasma gas tube is in fluid communication with the discharge chamber and provides a plasma gas thereto. Accordingly, the plasma gas can be used to maintain microplasma discharge between the electrodes and the sample gas can be introduced into the microplasma discharge. A spectrometer optically connected to the handheld/portable detector is used to measure the radiation emitted by the sample gas when subjected to the microplasma discharge.

Abstract: The present invention includes a new, sensitive, rapid, portable, and inexpensive biosensor for detection of biological agents. The inventors develop a mesoporous-chip based biosensor device that is able to detect very low-level pathogens in a relatively short time. This biosensor device is designed in a way that significantly increases the reaction area, and constructed by immobilizing antibodies onto a mesoporous chip surface. The antibody-immobilized mesoporous chip is used as a bioseparator for separation of pathogens or other biological agents when the sample goes through the chip pores. Then an enzyme labeled antibody solution is injected into the chip pores, and a sandwich structure of immuno-complexes (enzyme labeled antibody-biological agent-antibody immobilized on chip) can be formed within the chip pores. The porous chip will also be a bioreactor for catalysis of the enzyme reaction, resulting in easily detected chemical species.

Abstract: An apparatus for creating an atmospheric mini-plasma. The apparatus uses both a plasma support gas and a plasma reactive gas attached to a conduit in communication with a plasma generating region. The plasma generating region is designed with a gas inlet leading to a tube containing two parallel electrodes. The electrodes are attached to a direct current, continuous or pulsed, power supply that provides the electrical potential to create the atmospheric mini-plasma. The atmospheric mini-plasma discharges from the generating region opposite to the gas inlet. As the design of the plasma generating region is relatively small, a plurality of generating regions may be coupled together in an array. The additional feature of a pulsed power supply allows a compact design that is portable for field use.

Abstract: A handheld/portable detector for chemical vapor monitoring includes a housing and a discharge chamber that is established therein. The plasma discharge has a relatively small volume, e.g., in the micro-liter range. A first electrode and a second electrode are disposed within the discharge chamber and a discharge gap is established therebetween. A sample gas tube is in fluid communication with the discharge chamber and provides a sample gas to the discharge chamber. Also, a plasma gas tube is in fluid communication with the discharge chamber and provides a plasma gas thereto. Accordingly, the plasma gas can be used to maintain microplasma discharge between the electrodes and the sample gas can be introduced into the microplasma discharge. A spectrometer optically connected to the handheld/portable detector is used to measure the radiation emitted by the sample gas when subjected to the microplasma discharge.

Abstract: Provided is a novel system for conducting elemental measurements using cavity ring-down spectroscopy (CRDS). The present invention provides sensitivity thousands of times improved over conventional devices and does so with the advantages of low power, low plasma flow rate, and the ability being sustained with various gases.

Abstract: A low-power, plasma source-based, portable molecular light emission generator/detector employing an atmospheric pressure pulsed-plasma for molecular fragmentation and excitation is described. The average power required for the operation of the plasma is between 0.02 W and 5 W. The features of the optical emission spectra obtained with the pulsed plasma source are significantly different from those obtained with direct current (dc) discharge higher power; for example, strong CH emission at 431.2 nm which is only weakly observed with dc plasma sources was observed, and the intense CN emission observed at 383-388 nm using dc plasma sources was weak in most cases. Strong CN emission was only observed using the present apparatus when compounds containing nitrogen, such as aniline were employed as samples. The present apparatus detects dimethylsulfoxide at 200 ppb using helium as the plasma gas by observing the emission band of the CH radical.

Abstract: There has been invented a process for analyzing ambient air in a microwave induced plasma without use of an additional carrier gas. There has also been invented an apparatus for analyzing ambient air, other sample gas, or nebulized and desolvated liquids wherein a novel arrangement of plasma gas and sample gas conduits is used to enhance dependability of the plasma. This apparatus embodiment of the invention has a concentric arrangement of plasma gas and sample gas conduits so as to provide a sheath of plasma gas both within and surrounding the flow of analyte into the plasma region. The microwave plasma torch can either be contained within a sealed housing or can be operated in ambient air at ambient pressures. The microwave plasma torch of this invention is portable and can be operated continuously for real-time analysis of air.

Abstract: Electronic absorption spectroscopy of a polyaniline film deposited on a polyethylene surface by chemical oxidation of aniline monomer at room temperature was used to quantitatively detect ammonia gas. The present optical ammonia gas detector was found to have a response time of less than 15 s, a regeneration time of less than 2 min. at room temperature, and a detection limit of 1 ppm (v/v) for ammonia, with a linear dynamic range from 180 ppm to 18,000 ppm.