摘要:
Systems and devices relating to a biconical antenna. The antenna has a top cone assembly and a bottom cone assembly, each cone assembly being coupled to a dielectric spacer at its apex. Each cone assembly has a cone section and a truncated cone section. The cone section is a cone with an apex which forms the apex of the cone assembly. The truncated cone section is coupled to the cone of the cone section at the cone's rim. The cone has an opening angle which is larger than the opening angle of the truncated cone. The biconical antenna can be fed by way of a coaxial cable with the outer cable feeding the bottom cone assembly and the inner cable feeding the top cone assembly.
摘要:
A method and apparatus for photon counting are disclosed. In an implementation, the present disclosure provides a dynamic-range photon-counting spectrometric sensor for low signal detection embedded in large parasitic background light signal. Rather than using a known forward illuminated imager approach of counting photons directly, embodiments of the present disclosure use a backward illuminated imager approach to generate a burst of electrons based on the photons, and perform photon detection by counting the generated burst of electrons using the plurality of CMOS chip pixels. An electronic circuit, in communication with the CMOS chip pixels, includes a fast clock enabling discrimination between electrons in time. The electronic circuit can be built on the face of a semiconductor wafer on which the CMOS chip pixels are provided.
摘要:
The present invention provides a dielectric resonator antenna comprising: a dielectric resonator; a ground plane, operatively coupled with the dielectric resonator, the ground plane having four slots; and a substrate, operatively coupled to the ground plane, having a feeding network consisting of four microstrip lines; wherein the four slots are constructed and geometrically arranged to ensure proper circular polarization and coupling to the dielectric resonator; and wherein the antenna feeding network combines the four microstrip lines with a 90 degree phase difference to generate circular polarization over a wide frequency band.
摘要:
A multibranched N-doped carbon nanotube (CNT) and the process of production are described. The CNT includes a first-stage stalk having a direction comprising a first-stage base, and a first-stage top opposite to and attached with the first-stage base, at least two second-stage bundles, each of which comprises a second-stage base attached to the first-stage top, and second-stage top opposite to and attached with the second-stage base, and wherein the second-stage bundles branch from the first-stage stalk in substantially the direction of the first stage stalk, and a plurality of third-stage nanotubes each of which comprises a third-stage base attached to the second-stage top, a third-stage top opposite to and attached with the third-stage base, and wherein the plurality of third-stage nanotubes branch from the second-stage bundles.
摘要:
Disclosed herein is a compound having Formula I: or a salt thereof, in which R1, R2 and R3 are as defined herein. Also disclosed are processes to prepare compounds of Formula I and use of compounds of Formula I to prepare stable glassy phases.
摘要:
Methods and systems for presenting document search results to a user. A user enters search terms to be matched with indicators mentioned in documents from a specific corpus of documents. The search results, which are the documents with indicators or content that match the search terms, are provided to the user using a user interface. Each document in the search results are represented by a marker on a map in the user interface. Other indicators which appear with the searched for indicators in the documents are also mapped to the user interface. Documents with similar indicators in their content are clustered together in the map and the markers which represent them are color coded to differentiate them from markers belonging to other clusters.
摘要:
A method for effecting physicochemical transformations and detonation properties in a material using super-compressed detonation includes: providing an insensitive energetic material to be compressed; super-compressing the material by exposure to at least one of a normally or obliquely oriented cylindrical imploding shock wave, generated from a first detonation; effecting transformations from the super-compression in the material including increasing at least material density, structural transformations and electronic energy gap transitions relative to a material unexposed to the super-compression; exposing the super-compressed material to a second detonation; and effecting transformations from the second detonation in the material including increasing at least detonation pressure, velocity and energy density relative to a material unexposed to the super-compression and second detonation.
摘要:
Carbon nanostructures for use as catalyst supports in hydrogen fuel cells are produced by mixing a carbon material with at least one transition metal such as iron and cobalt, subjecting the mixture thus produced to mechanical grinding, e.g. ball milling in a hydrogen atmosphere for a time sufficient for hydrogen to be absorbed into the mixture, and heating the mixture in an inert atmosphere at a temperature sufficient to crystallize at least one of the carbon material and carbide nanocrystals.
摘要:
This invention discloses methods for identifying Francisella tularensis vaccine candidates. It enables identification of novel vaccine candidates and quality assurance for vaccine batches, assessment of protection in vaccinates and identification of the infecting agent in vaccinates. Mice were first vaccinated with Brucella abortus O-polysaccharide (OPS) vaccine. These animals were then given 10 LD50s of F. tularensis live vaccine strain (LVS). Sixty percent (60%) of the vaccinated mice survived the multiple lethal doses. Sera were collected from these surviving mice and the antibodies were used to probe supernatant and cell lysates of live F. tularensis LVS cultures. Several F. tularensis components were identified only by the noted “survivor” antisera. Of these identified proteins, enzyme digestions and chemical oxidation suggest post-translational modifications of some proteins e.g. a 52 kDa glycoprotein, a 45 kDa lipoprotein and a 19 kDa nucleoprotein. The 52 kDa component caused nitrous oxide induction in tissue cultures at low concentrations, cell death at high concentrations. Vaccination with this gave partial protection while addition of other components acted synergistically to give enhanced protection from 250 LD50s of F. tularensis LVS.
摘要:
A portable low frequency underwater acoustic projector having two circular diaphragms separated by a spacer ring with a pair of coils and oscillating masses being located in pipes connected to central opening in two diaphragms, the coils driving these masses in opposite directions. Central openings in each diaphragm have an associated pipe extending outward from the interior of the projector, the pipe having closed outer ends. The interior of the projector being gas filled to provide pressure compensation.