273results about "Analysis using electron paramagnetic resonanace" patented technology

The present disclosure provides a method of monitoring a property of a sample, such as a nanoscopic property of the sample. The method comprises the steps of providing a quantum probe having a quantum state and exposing the quantum probe to the sample in a manner such that the property of the sample, in the proximity of the quantum probe, affects quantum coherence of the quantum probe. The method also comprises detecting a rate of quantum decoherence of the quantum probe to monitor the property of the sample. Further the present disclosure provides an apparatus for monitoring a property of a sample.

An electron spin resonance spectrometer includes a bridge to transmit an excitation frequency and to receive a signal frequency; a probe electrically connected to the bridge and comprising: a first conductor in electrical communication with the bridge to transmit the signal frequency to the bridge; a shorting member electrically connected to the first conductor to transmit the excitation frequency to a sample, to produce the signal frequency, and to transmit the signal frequency to the first conductor; and a second conductor electrically connected to the shorting member; and a magnet disposed proximate to the probe.

A sensing probe may be formed of a diamond material comprising one or more spin defects that are configured to emit fluorescent light and are located no more than 50 nm from a sensing surface of the sensing probe. The sensing probe may include an optical outcoupling structure formed by the diamond material and configured to optically guide the fluorescent light toward an output end of the optical outcoupling structure. An optical detector may detect the fluorescent light that is emitted from the spin defects and that exits through the output end of the optical outcoupling structure after being optically guided therethrough. A mounting system may hold the sensing probe and control a distance between the sensing surface of the sensing probe and a surface of a sample while permitting relative motion between the sensing surface and the sample surface.

An n-NV-based gyroscope is provided that includes a diamond structure implanted with a plurality of NV centers, whose nuclear spins form a spin gyroscope. A number of radio-frequency (rf) coils and microwave (μw) co-planar waveguides are fabricated on the diamond structure to provide a sensitive and stable three-axis gyroscope in the solid state while achieving gyroscopic sensitivity by exploiting the coherence time of the 14N nuclear spin associated with the NV centers in the diamond structure combined with the efficient optical polarization and measurement of electronic spin.

A zero-field paramagnetic resonance magnetometer (ZF-PRM) system and method for quickly and efficiently finding and optimizing the zero-field (ZF) resonance is described. In this system and method a magnetic coil is used to apply a magnetic bias field in the direction of the pump beam to artificially broaden the width and maximize the strength of the ZF resonance. By making the ZF resonance easy to detect, the ZF resonance may be found quickly found without the use of additional components and complex algorithms. Once the ZF resonance is found, a compensating magnetic field can be applied to null the magnetic field in the vicinity of the vapor cell in the ZF-PRM, thereby initializing it for operation.

A thin plate of synthetic single crystal diamond material, the thin plate of synthetic single crystal diamond material having: a thickness in a range 100 nm to 50 μιη; a concentration of quantum spin defects greater than 0.1 ppb (parts-per-billion); a concentration of point defects other than the quantum spin defects of below 200 ppm (parts-per-million); and wherein at least one major face of the thin plate of synthetic single crystal diamond material comprises surface termination species which have zero nuclear spin and / or zero electron spin.

Methods and systems for spatially resolved spin resonance detection in a sample of material are disclosed. Also disclosed are methods and systems for spatially resolved impedance measurements in a sample of material. The disclosed methods and samples can be used in screening of plurality of biological, chemical and material samples.

Provided are methods of detecting the presence or amount of a vitamin D metabolite in a sample using mass spectrometry. The methods generally comprise ionizing a vitamin D metabolite in a sample and detecting the amount of the ion to determine the presence or amount of the vitamin D metabolite in the sample. Also provided are methods to detect the presence or amount of two or more vitamin D metabolites in a single assay.

This invention concerns an electronic device for the control and readout of the electron or hole spin of a single dopant in silicon. The device comprises a silicon substrate in which there are one or more ohmic contact regions. An insulating region on top of the substrate. First and second barrier gates spaced apart to isolate a small region of charges to form an island of a Single Electron Transistor (SET). A third gate over-lying both the first and second barrier gates, but insulated from them, the third gate being able to generate a gate-induced charge layer (GICL) in the ESR line substrate beneath it. A fourth gate in close proximity to a single dopant donor gate atom, the dopant atom being encapsulated in the substrate outside the region of the GICL but close enough to allow spin-dependent charge tunnelling between the dopant atom and the SET island under the control of gate potentials, mainly the fourth gate. In use either the third or fourth gate also serve as an Electron Spin Resonance (ESR) line to control the spin of the single electron or hole of the dopant atom. In a further aspect it concerns a method for using the device.

The invention discloses a method for measuring atomic transverse relaxation time based on an electron resonance phase frequency analysis. In a strong-background magnetic field with almost neglected residual magnetization in a magnetic shielding barrel, a swept-frequency signal that has a bandwidth covering a resonance curve and has an amplitude enabling the resonance curve to have a clear curve under low polarizability is applied in a horizontal direction; an optical swing angle signal of a magnetometer is detected and a spectral analysis is carried out on an outputted signal in a polar coordinate system to obtain a phase frequency response function of the magnetometer; the phase frequency response function is fitted to a corresponding theoretical phase frequency curve of the magnetometer to obtain atomic spinning transverse relaxation time. Because the phase angle is a result obtained by quotient processing of a spinning transverse component, the influence of common coefficient fluctuation is suppressed, so that the phase frequency signal expression is more stable by being compared with amplitude-frequency signal expression. Besides, the theoretical phase frequency curve is not affected by the magnetic induction intensity of the transverse magnetic field and the atomic spinning longitudinal relaxation time, so that complexity of data processing can be reduced. Moreover, a lorenz curve widening risk caused by the transverse magnetic field can be eliminated.

A miniaturized instrument and method of using electron spin resonance spectrometry for measuring the degradation of lubricating fluids, and the like, that includes continuously passing a sample of such fluid through a resonating RF microwave cavity resonator during the application therethrough of a uniform slowly varying uniform magnetic field that is rapidly modulated and measuring the resulting phase modulation or amplitude modulation thereof to derive an electron spin resonance signal that directly senses the molecular changes in the fluid sample resulting from fluid degradation during operation of the vehicle, such as peroxy radicals in vehicle engine oil and the like.

The invention belongs to the technical field of preparation of quantum dot nanometer materials, and particularly relates to an aqueous phase synthesis method for transition metal Mn doped ZnSe quantum dots. The method comprises the steps of utilizing inorganic metal water-soluble compounds such as zinc nitrate, manganese chloride and the like and carboxylic acid reagents containing sulfhydryl groups as raw materials, and doping transition metal Mn into ZnSe semi-conductor nano-particles in aqueous solution by a nucleation doping method. The method has the advantages of mild reaction conditions, simple and safe operation, and good repetitiveness, eliminates the toxicity caused by the use of heavy metal elements in the prior quantum dots, and successfully synthesizes non-toxic quantum dots emitting yellow visible light. The quantum dots can be taken as a fluorescent marker to be widely applied to cell and tissue imaging due to low toxicity, and can be applied to in vivo imaging research.

A method of and miniaturized apparatus adapted for in-situ measurement of degradation of automotive fluids and the like by micro-electron spin resonance (ESR) spectrometry, wherein the use of a modulated constant magnetic field in an RF resonating variable frequency microwave cavity resonator through which a fluid sample is passed, enables direct detection of molecular changes in such fluid sample resulting from fluid degradation during use.

Provided is a technique for making two-dimensional magnetic measurement with high sensitivity possible at normal temperature in the atmosphere. The diamond crystal pertaining to the present invention is characterized by having an NV region including a complex (NV center) of nitrogen substituted for a carbon atom and a vacancy adjacent to the nitrogen on or near the surface thereof, the NV region having a donor concentration equal to or greater than the concentration of the NV center, or the crystal in the NV region being the (111) face or a face having an off angle no more than + / -10 degrees of the (111) face, and the principal axis of the NV center being a < 111 > axis orthogonal to the (111) face. Through such a diamond crystal, substantially 100% of the NV center can be placed in a negatively charged state (NV-), the spin state of the NV- center can be aligned in one direction, and ODMR signal peaks also become sharp. Through the sensor array pertaining to the present invention, the NV center generated in the diamond crystal can be maintained in the negatively charged state (NV-).

A diamond crystal according to the present invention has an NV region containing a complex (NV center) of nitrogen substituted with a carbon atom and a vacancy located adjacent to the nitrogen, on a surface or in the vicinity of the surface, wherein the NV region has a donor concentration equal to or higher than the concentration of the NV centers, or a crystal of the NV region is a {111} face or a face having an off-angle that is ±10 degrees or less against the {111} face, and a principal axis of the NV center is a <111> axis that is perpendicular to the {111} face. Such a diamond crystal enables almost 100% of the NV center to be a state (NV−) of having a negative electric charge, and spin states of the NV− centers to be aligned in one direction.

A method for performing magnetic resonance measurements on a sample includes applying a first predetermined number of pulse trains for excitation, each pulse train having a constant amplitude and including a second predetermined number of pulses spaced by a predetermined time interval. The pulse trains are modulated by a bent function. After each pulse, data is sampled. Preferably a square number of pulses is generated being constant in power, and the Walsh transform of the sequence of their phases is constant in power, so that the power of the excitation in time and frequency domain is constant. The method can reduce power requirements and may permit undercutting specific absorption rate (SAR) limits due to the small excitation power necessary to create time signals with reasonable signal to noise ratio.

The invention discloses a method for detecting free radical ration in coal tar. The method comprises the steps of removing moisture in the tar in a high speed centrifuging manner, and preserving a tar sample under low temperature or inert atmosphere; adopting a diamagnetism substance to deliquate DPPH(1,1-Diphenyl-2-picrylhydrazyl radical 2,2-Diphenyl-1-(2,4,6-trinitrophenyl) hydrazyl) to prepare a plurality of DPPH standard samples with different free radical concentrations, carrying out EPR (electron paramagnetic resonance) measurement, carrying out secondary integration on an EPR spectrogram, and recording the corresponding secondary integration area; establishing a standard curve according to the free radical contents of the DPPH standard sample with different free radical concentrations and the secondary integration area of the corresponding EPR spectrogram; and filling the tar sample into a pipe, measuring according to the same EPR measuring condition, carrying out secondary integration on the measured EPR spectrogram, and substituting the secondary integration area into the standard curve so as to obtain the free radical content N. The method provided by the invention can exactly measure free radical content in coal tar, meanwhile, the change of the content of the free radical in the coal tar along with the preservation condition is exactly measured, and the method for detecting ration is provided for the research of the free radical in the coal tar and is very simple and easy.

The invention relates to a method for continuously detecting the smoke discharge, which comprises: a, the smoke of tube is sampled by the sampling detector; b, the sample smoke is fed into heater, to be preheated and fed into the heating measure pool; c, using spectrum analyze technique to measure the density of at least one tested gas or the material which is gas when heated but not gas in normal temperature in the pool. The invention also discloses a relative detecting system. The invention has low error, low cost, and high response speed.

The invention discloses a measurement method and measurement system of zero-field paramagnetic resonance. According to the measurement method, a paramagnetic resonance spectrum of target electrons ismeasured by utilizing an NV color center in a diamond base material as a probe; a zero-field condition is utilized, adverse effects caused by molecule random orientation can be resisted and the Zeemaneffect generated by an external electric field can be eliminated, so that a needed energy grade structure is directly detected. For example, a space structure of a molecule can be obtained through analyzing an electron-electron fine interaction effect; a local polar environment of the molecule can be obtained through analyzing an electron-nuclear spin superfine interaction effect; a precision displacement device, an optical co-focusing device and an NV color center probe are combined, and the precision displacement device and a co-focusing microscopic device can realize accurate finding and detection of the NV color center; the NV color center is a single-electron probe and has a nano-scale resolution capability, so that a nano-scale detection capability is realized.

ESR imaging probe, system, and method are described. The probe is an ex-situ probe, the system comprises the probe and configured for operating the probe, and the method comprises detecting ESR from outside a resonator of the probe. An exemplary embodiment of a probe according to the invention comprises a cooled dielectric resonator, and one sided gradient coils. An exemplary embodiment of the system comprises source current that is configured to supply to the gradient coils currents of up to 100 A in pulses shorter than 1 μsec.

The invention discloses a surface self-assembly gold nanoprobe with the free radical capture performance and a preparing method and the application thereof. The surface self-assembly gold nanoprobe with the high free radical capture performance is prepared by the following steps: the surface of a gold nano-particle is connected with nitrone free radical probe ligand with the structure of formula II by a connexon of the structure of formula I. The nitrone free radical probe ligand is connected with R3 radical group end. The gold nano-particle is connected with sulfhydryl end of the connexon. In formula Ia and formula Ib, R3 is -OH, -NH2 or -COOH, n is equal to 2-11, and n1 is equal to 1-4. In formula IIc, R1 is -P(O)(OC2H5)2, and R2 is OH, COOH or CH2OH. The surface self-assembly gold nanoprobe with the high free radical capture performance can capture free radicals under low concentration and can be applied as an antioxidant.

The invention provides a method for diagnosing soil pollution condition by using earthworm biomarkers, and belongs to the technical field of soil pollution monitoring and control. In the method, artificially cultured earthworm is used as a standard test animal; four oxidative damage test indexes, namely oxygen free radical, malondialdehyde content, protein carboxyl content and reductive glutathione-oxidative glutathione proportion, are used as the biomarkers for diagnosing soil pollution; clean artificial soil is used as standard soil; and the pollution condition of the tested soil can be quickly and sensitively diagnosed by analyzing the difference of the four oxidative damage indexes in vivo of the earthworm after the earthworm is cultured in the clean artificial soil and the tested soil for certain time. The method can be used for comprehensively diagnosing the soil pollution condition and the health degree, and the method has good sensitivity for trace pollutants in the soil and can be used as a monitoring method for soil pollution early warning. Compared with a chemical analysis method, the method has the characteristics of simple operation and low cost.

An instrument and method using electron spin resonance spectrometry for measuring the concentration of airborne soot particles, and the like, that includes continuously passing a sample of exhaust gas through a resonating RF microwave cavity resonator during the application therethrough of a uniform slowly varying uniform magnetic field that is rapidly modulated and measuring the resulting phase modulation or amplitude modulation thereof to derive an electron spin resonance signal that directly senses the concentration of carbon free radicals produced as a result of inefficient combustion of hydrocarbons during operation of the vehicle or boiler. A further invention is the use of this signal for feedback control of the engine or boiler operating parameters to minimize or substantially eliminate particulate matter emissions.

The invention discloses a method for detecting diamond color center spin in a sensing way based on a microwave phase modulation spectroscopy technology. The method comprises the following steps: (1) symmetrically installing a microwave transmitting end (4) and a microwave receiving end (5) at the inner side of a diamagnetic circular ring (8), wherein the microwave transmitting end (4) is connected with a microwave source, and the microwave receiving end (5) is connected with a data acquisition port of a field programmable gate array (FPGA) or a signal input end of an oscilloscope card, or the microwave receiving end (5) is respectively connected with the signal input end of the oscilloscope card and the data acquisition port of the FPGA by a port divider. According to the method, resonance signals of diamond color center atoms are detected in combination of the microwave phase modulation spectroscopy technology, the electronic energy level is excited by using laser, an external magnetic field is scanned, and the change of microwave signals is detected by means of an absorptive action of a diamond color center ground state energy level for a microwave field, so that color center spin information is read. The detection method is simple and convenient and high in accuracy, eliminates the complexity and instability of a light path, and increases the signal-to-noise ratio of atomic magnetic resonance.