摘要:
A radio frequency (RF) data carrier is presented. The RF data carrier comprises at least one diffraction element that has a dimension of the order of a wavelength of RF radiation and is responsive to RF irradiation, the response produced by the diffraction elements in the data carrier being indicative of machine-readable data carried by data carrier.
摘要:
A radio frequency (RF) data carrier and method and system for reading information stored in the data carrier are presented. The data carrier comprises a collection of circuitries defining together a predetermined information code. Each circuitry includes: (a) a code circuit configured to have a certain RF frequency response to a powering signal and thus defining a certain symbol of the predetermined information code, and (b) a delay circuit configured to provide a phase delay of a predetermined value to said powering signal associated with the respective code circuit to thereby define a location of this symbol in the information code. The data carrier further comprises a power unit operable to produce said powering signal to actuate the delay circuit. The power unit comprises at least one inductance coil responsive to alternation of an external magnetic field for generating said powering signal as an electromotive force voltage as a result of intersecting windings of the coil with magnetic flux lines of the external magnetic field.
摘要:
A method and system for producing a liquid fuel comprising: (a) reacting water with a first metal in a first reaction chamber to obtain hydrogen, heat, and an oxide of the first metal; (b) reacting carbon dioxide with a second metal, which is the same or different from the first metal, in a second reaction chamber, which is the same or different from the first reaction chamber, to obtain carbon monoxide, heat, and oxide of the second metal; (c) regenerating said first and second metals from said first and second oxides.
摘要:
Described are methods and systems for producing synthesis gas. In some embodiments, the method includes microbiologically converting biological material to form methane and CO2; and reacting methane and CO2 formed in (a) with water and metal to form synthesis gas. Optionally, the method also includes cutting vegetation; fermenting the vegetation to form biogas comprising methane and CO2; and reacting the biogas with water and metal to form synthesis gas and metal oxide. In some embodiments of the invention, reacted metal is regenerated from metal oxide produced in the reaction. In some embodiments the regeneration comprises reacting the oxide in a bath of boiling zinc.
摘要:
A solar energy system comprises a solar absorber in the form of a solar boiler tank with a lower working liquid region having a liquid inlet and filled with a working liquid capable of boiling under a predetermined pressure, and an upper vapor accumulation region having a vapor outlet for withdrawing from the tank a vapor created in the tank. The system further comprises vapor utilization means associated with the vapor outlet. The solar boiler tank has at least one transparent window to receive and pass towards the working liquid highly concentrated solar radiation. The system also comprises means for controlling the pressure of vapor in the vapor accumulation region to make the working liquid boil at the predetermined pressure.
摘要:
A two layer system for heat energy capture and storage with an upper or lower layer for heat extracting and the other layer for heat transfer. Either layer can function as a phase change material. Heat stored is conducted externally of the system and can be used directly in a converting system, i.e., heat to mechanical or electrical energy or transferred as heat for further applications.
摘要:
A solar radiation concentrating system (1) comprises at least two reflectors (12, 16) successively arranged along an optical path (4) of the system (1) so that a first (12) of the two reflectors (12, 16) reflects the radiation towards a second (16) of the two reflectors (12, 16). The reflectors (12, 16) have such spectral characteristics as to be capable of highly reflecting the radiation in a reflection range of wavelengths and absorbing the radiation in an absorption range of wavelengths, wherein the absorption range of wavelengths of the first reflector (12) substantially includes the absorption range of wavelengths of the second reflector (16).
摘要:
High radiation concentration photovoltaic cell system including at least one optical structure in the form of a three-dimensional body having a first surface adapted to receive thereon photovoltaic cells and a second surface to be, at least indirectly, exposed to light radiation. The body of the optical structure has formed between its first and second surfaces a two-dimensional array of contiguous light radiation concentrators each in the form of an individual prismatic body portion. Each prismatic body portion tapers in two dimensions toward said first surface along the entire length of the concentrator. Each concentrator defines on the first surface a photovoltaic cell-attaching area to be aligned with an active portion of a single photovoltaic cell to be attached thereto. The system may further include at least one separate distantly located solar radiation collecting and/or reflecting sun-tracking device arranged to direct solar radiation to be impinged in two dimensions on the second surface of the entire array of the radiation concentrators.
摘要:
A laser apparatus of the end pumping kind in which an elongated transparent laser element is mounted in spaced relationship within a tubular waveguide which has a highly reflective inner surface. The arrangement is such that, at least along part of the laser element, the optical distances between different points on the surface of the laser element and the inner contour of the waveguide vary.
摘要:
A composite working fluid for a Rankine cycle power plant operating between a boiler temperature and a condenser temperature comprises a mixture of immiscible fluids selected such that the saturated vapor line of the composite fluid in the vicinity of the boiler temperature is generally along a line of substantially constant entropy. As a result, the vapor of the composite working fluid expands from boiler to condenser temperature generally along the saturated vapor line of the composite working fluid. One of the immiscible fluids of the composite working fluid is a "wet" fluid, and one of the immiscible fluids is a "dry" fluid. The "wet" fluid is a polar compound with a molecular weight smaller than the molecular weight of the "dry" fluid, which is a non-polar compound. Preferably, the "wet" fluid is water, and the "dry" fluid is selected from a class comprising hydrocarbons and their halogenated derivatives.