34results about How to "Short pulse time" patented technology

The invention relates to a method for testing mechanical property of a material under the action of stress wave, in particular to a method and a device for measuring dynamic fracture property of a laser shock loading material. The method comprises the following steps of: loading a three-point bent sample (4) with preformed crackles (1) by using shock wave induced by nanosecond-scale laser pulse (8), and detecting the propagation property of the stress wave (17) in the three-point bent sample (4) and the expansion property of the crackles by adopting a method of combining photo-elasticity and moire. The device acquires a high-speed transient photo-elastic image of interaction of the material and the stress wave under the condition of a high loading rate by using a multi-spark camera optical system (13), can clearly observe the propagation of the laser-induced short pulse stress wave (17), and can accurately and reliably acquire the fracture property of the material by processing.

The invention relates to a vacuum diode with high current, small focal spot and long service life. The original diode in a repetition frequency fast-pulse hard X-ray generator is modified, the structure and the material of movable cathode and anode assemblies are improved, a cathode head is made of tungsten nickel copper alloy materials and is seated on a movable support, a conical hole structure inwards forming a sharp end bulge is used for emitting electrons and is aligned with X rays, and an anode target is made of metal tantalum materials and is fixedly arranged on a copper core wire through screw threads. The conical annular cathode structure is improved, the radius of sent plasmas is favorably controlled, dense plasmas can be conveniently obtained, the self pinching condition in the electronic beam transporting process is met, submillimeter beam spots are formed, and the detailed imaging requirement of the pulse imaging field is met.

The invention belongs to the technical field of displacement compressor, and relates to a radial multi-cylinder synchronization rotary compressor. The radial multi-cylinder synchronization rotary compressor comprises a crank shaft driven by a motor, a cylinder and a cylinder cover of a cylinder body, a bearing supporting the crank shaft, a stander and a piston making reciprocating movement in the cylinder body, and is characterized in that at least one set of bidirectional piston and a cylinder corresponding to the bidirectional piston are arranged on the crankshaft driven by the motor and on the same plane vertical to the crankshaft, wherein the bidirectional pistons are distributed circumferentially and are provided with a rotating center respectively. The crank shaft, the cylinder body and the pistons can rotate synchronously along the rotating centers respectively. An intake, an exhaust port, an intake and an exhaust valve are arranged on the cylinder cover or the piston bodies. The radial multi-cylinder synchronization rotary compressor has the advantages of small size, good heat radiating effect, low noise, good air-tightness, high working efficiency and therefore is suitable for spreading application on the same type of compressor.

The invention discloses a high-brightness pulse white-light source exciting system. A focusing lens assembly and an air chamber are sequentially arranged on a light path of laser pulses output by a nanosecond-pulse laser. The laser pulses are focused into the air chamber through the focusing lens assembly, light emitted by generated plasma flame is collected by an optical collecting device, and a high-brightness pulse white-light source is obtained. The collected white light of the high-brightness pulse white-light source exciting system can be used for spectral analysis, imaging, illumination, photoetching, transfer printing and other fields. The high-brightness pulse white-light source exciting system achieves white light output which is short in pulse time, high in instantaneous strength, stable in time and spectral property, and wide in spectral region.

The invention discloses a tungsten probe composite diamond-like coating layer; the coating layer is composed of a tungsten probe matrix, a bottom adhesive layer and a surface layer in sequence, the bottom adhesive layer is metal titanium, and the surface layer is a diamond-like coating layer. The preparation method adopts a negative electrode filter electric arc technology, an ion beam technologyand a vacuum sputtering technology are combined, the composite diamond-like coating layer is deposited on a sample substrate, and the obtained composite diamond-like coating layer has the advantages of high film-substrate bonding strength, low internal stress, low friction coefficient, good uniformity and long wear resistance.

The invention discloses a method for breeding an high-yield ascomycin strain by performing femtosecond laser mutagenesis on streptomyces hygroscopicus ascomycota subspecies and a culture medium preparation method; the method comprises the following steps: at room temperature, mixing mature slant spores of the streptomyces hygroscopicus ascomycota subspecies (ATCC14891) and sterile water to obtain monospore suspension containing 106-107 spores per milliliter; irradiating the spore suspension for 1-10 min by using the titanium sapphire femtosecond laser with centre wavelength of 800 nm, pulse width of 150 fs and frequency of 76 MHz under a irradiation power of 10-30m W; properly diluting the spore suspension, coating on a solid panel to culture, then screening by using a shake flask to obtain a high-yield ascomycin mutation strain. The method provided by the invention has the advantages that the used femtosecond laser mutagenesis method is feasible and safe to operate; the mutation effect is better than that of the traditional physical and chemical mutagenesis method, and the femtosecond laser mutagenesis method has great popularization value in breeding of microorganism pharmaceutical strains; by using the femtosecond laser irradiation to perform the mutagenesis, the high-yield ascomycin mutation strain can be bred. The positive mutation rate of the mutation strain is 5-30%, and fermenting unit is improved by 10-60% in comparison with that of an original strain.

The invention provides a fault current suppression method and system for a double-electrical-port variable-flux motor and a medium, and the double-electrical-port variable-flux memory motor comprises a stator core and a three-phase AC armature winding disposed on the stator core. The three-phase alternating-current armature winding comprises a first armature winding, a second armature winding, a rotor iron core and a demagnetized permanent magnet placed on the rotor iron core, and the two sets of armature windings of the motor are independently controlled; and the electric machine is driven by a controller comprising three-phase inverters including a first inverter and a second inverter, the first inverter being electrically connected to the first armature winding and the second inverter being electrically connected to the second armature winding. Under the condition that a motor system breaks down, the residual healthy alternating-current armature winding and the inverter are reasonably controlled, the fault back electromotive force is reduced, and the fault current is restrained; and the method is suitable for occasions with high fault tolerance requirements, and application objects include but are not limited to high-reliability vehicle driving motors, high-power marine driving motors and high-capacity wind driven generators.

The invention discloses a method for preparing an aluminum-based amorphous layer by jointly adopting hot spraying and electron beam remelting technologies, and relates to the technical field of preparation of an aluminum-based amorphous coating. The method comprises the steps of preparing an Al-Co-Ce alloy, carrying out a gas atomization process on the alloy so as to powder, then utilizing a supersonic speed flame for hot-spraying a substrate surface so as to prepare an Al-Co-Ce alloy protection coating, and finally adopting a high-current pulse electron-beam for carrying out surface modification on the prepared Al-Co-Ce alloy protection coating, wherein the Al-Co-Ce alloy is prepared from 4.0 to 8.0 at percent of Co, 6.0 to 8.0 at percent of Ce and the balance Al. According to the methodfor preparing the aluminum-based amorphous layer by jointly adopting the hot spraying and electron beam remelting technologies provided by the invention, surface modification is carried out on the surface of a hot-spraying coating, so that the amorphous alloy layer with a flat surface and a compact structure is generated, and the corrosion resistance of the hot-spraying coating is improved.

The invention provides an engine air cylinder sleeve-piston ring laser shot blasting method which comprises the following steps: S1, dipping degreasing cotton in absolute ethyl alcohol to wipe the surface of an air cylinder sleeve-piston ring so as to remove oil dirt on the surface of a part; S2, pasting an aluminium foil adhesive tape as an absorption layer on the to-be shot blasted surface of the air cylinder sleeve-piston ring; S3, controlling the water flow, and arranging a restraint layer by spraying deionized water on the absorption layer; and S4, clamping and fixing the air cylinder sleeve-piston ring on the clamp of an operating platform, and adjusting the laser path to start laser shot blasting so as to finish laser shot blasting modeling of the part. According to the engine air cylinder sleeve-piston ring laser shot blasting method, tiny concave pits on a surface subject to shot blasting has an oil storage function to realize an excellent lubricating function and reduce friction loss.

The invention relates to a mass spectrometer and an optical system thereof. The optical system adopts a mass spectrum ion source design based on a solid laser, has the advantages of long service life,short pulse time, small size, high repetition frequency and the like compared with an N2 laser, and is beneficial to improving the resolution of a mass spectrometer and reducing the maintenance frequency. Particularly, according to the optical system, a solid laser, a whole optical path system and a shell are completely fixed to an optical fixing platform, the optical path system is located in the shell, the structure is very stable, and installation and maintenance are convenient. During use, the size of a laser spot can be adjusted by adjusting the distance between a first focusing lens anda collimating lens, so that the invention is convenient to use.

The present invention relates to a point electrowelding welding head for the electronic industry and microelectronic industry. It comprises two parallel electrodes which are made of high-temp. resistant metal material, and combined together and an insulating layer sandwiched between two electrodes, and is characterized by that the said insulating layer is made up by adopting insulating viscose capable of producing fix-connecting adhesion and insulating separation actions simultaneously so as to save insulating rivet, and at the same time, the pointed portions of two parallel electrodes are made into the form of mutual ohmic contact so that it not only can directly weld enamelled wire, but also can obtain good welding effect for welding bare wire, metal sheet and metal tape, etc.

The invention provides a preparation method of a metal interconnection structure. The method comprises that a lower dielectric layer with an interconnection line is provided; an etching terminal detection layer rich in nitrogen, a porous interlayer dielectric layer, a low K buffer layer and a metal hard mask layer are formed on the lower dielectric layer successively; a photoresist layer with an open-mounted pattern is formed on the metal hard mask layer, and the cross sectional width of an opening is greater than that of the interconnection line; the metal hard mask layer and the low K bufferlayer are etched to form an opening structure; femto second laser etching is carried out on the porous interlayer dielectric layer by taking the opening structure as a mask; during detection, when the etching terminal detection layer rich in nitrogen is reached by etching, third etching is carried out, and a nitrogen reduction gas is input in the etching process; after that the interconnection line in the lower portion is exposed, nitrogen is input continuously to over etching the lower dielectric layer further and form an opening structure; and a barrier layer, a crystal seed layer and a metal layer are formed successively in the opening structure, and the metal interconnection structure is formed.

The invention relates to a pulse fiber laser taking a saturable absorber as an intensity modulation device, in particular to the field of lasers. According to the invention, a wavelength division multiplexer is optically connected with a pumping source, an erbium-doped fiber and one end of an output coupler; the other end of the erbium-doped optical fiber, the isolator, the polarization controllerand the optical modulator are optically connected in sequence; the other end of the optical modulator is optically connected with the other end of the output coupler, wherein the saturable absorber of the light intensity modulator is made of iron selenophosphite; and the iron selenophosphite is formed by stacking a plurality of thin layers. Compared with the prior art, the optical modulator prepared from the iron selenophosphate has the advantages that the optical modulator prepared from the iron selenophosphate has excellent light intensity modulation capacity, the pulse time of the pulse optical fiber laser is shorter due to the fact that the iron selenophosphate has a large modulation depth, and the cost of the optical modulator prepared from the iron selenophosphate is lower.

A laser diode device 1 includes a thermally conductive substrate 2 that has a planar surface for dissipating ambient heat, and a plurality of laser diodes 3 situated thereon, each of which includes atleast one epitaxial layer 4 that is situated on a side of the laser diode 3 facing the substrate 2. The laser diodes 2 are each electrically activated via an electrically conductive coating situatedbetween the at least one epitaxial layer 4 and the substrate 2. The substrate 2 includes a plurality of metallized cavities that accommodate the plurality of laser diodes 3 so that the plurality of laser diodes have an essentially uniform height above the substrate.

The invention provides a CO2 cascade ultraviolet Raman laser. High-purity CO2 gas is pumped by adopting quadruplicated frequency 266nm of an Nd: YAG laser, and three main ultraviolet light outputs of276nm, 287nm and 299nm are realized by utilizing cascade stimulated Raman scattering. By using double Raman pools, the energy output of Raman light of each order in the two Raman pools can be respectively regulated and controlled. Raman light output of different energy can be obtained by changing energy, pulse width, light beam quality and polarization state of incident pump light, pressure of CO2gas in the two Raman pools, focusing parameters and lengths of the Raman pools or filling buffer gas in the Raman pools and controlling types and pressure of the buffer gas. The laser has the advantages that the laser is simple in design and convenient to debug, simultaneous output of two atmospheric window pairs (276 nm/287 nm and 287 nm/299 nm) can be achieved, and the energy output values of the three beams of light can be regulated and controlled.