394results about How to "Improve launch performance" patented technology

A semiconductor light emitting element of nitride compound semiconductors excellent in cleavability, heat radiation and resistance to leakage is made by epitaxially grow a nitride compound semiconductor layers on a substrate of sapphire, for example, and thereafter separating the substrate. For separating the substrate, there are a technique using a abruption mechanism susceptible to a stress such as a "lift-off layer" and a recesses on a substrate. A technique using laser light to cause a local dense heat stress at the abruption mechanism is effective. A nitride compound semiconductor obtained by separating the substrate may be used as a new substrate to epitaxially grow high-quality nitride compound semiconductors thereon.

The present invention provides new compositions containing colloidal nanocrystals with high photoluminescence quantum yields, new synthetic methods for the preparation of highly luminescent colloidal nanocrystals, as well as methods to control the photoluminescent properties of colloidal nanocrystals. The new synthetic methods disclosed herein allow photoemission brightness (quantum yield) to be correlated with certain adjustable nanocrystal growth parameters associated with a given synthetic scheme.

Optoelectronic devices and methods for their fabrication having enhanced and controllable rates of the radiative relaxation of triplet light emitters are provided exemplified by organic light emitting devices based on phosphorescent materials with enhanced emission properties. Acceleration of the radiative processes is achieved by the interaction of the light emitting species with surface plasmon resonances in the vicinity of metal surfaces. Non-radiative Förster-type processes are efficiently suppressed by introducing a transparent dielectric or molecular layer between the metal surface and the chromophore. For materials with low emission oscillator strengths (such as triplet emitters), the optimal separation distance from the metal surface is determined, thus suppressing energy transfer and achieving a significant acceleration of the emission rate.

An organic electroluminescent device is provided and includes: a pair of electrodes; and a light emitting layer between the electrodes. The organic electroluminescent device has a layer containing a compound represented by formula (I).L represents a divalent linking group, Q1 and Q2 each independently represents an aromatic or aliphatic heterocycle coordinated to Pt through a nitrogen atom, X1 represents a 6-membered ring containing one or more nitrogen atoms, Q1, Q2, and X1 each independently may have a substituent, X2 represents a sulfur atom, a phosphorus atom, an oxygen atom, or a nitrogen atom, and X3 represents a carbon atom, a sulfur atom, or a phosphorus atom.

The invention provides an adaptive digital pre-distortion technique and device which is suitable for OFDM projector. The device comprises an OFDM baseband signal module for orthogonal frequency division multiplexing technique, a digital pre-distortion synthetic process component, an analog and digital converter DAC, a radio frequency projector, a wideband high power amplifier, i.e., W-HPA, and a feedback circuit. Wherein, a digital pre-distortion internal core, which is structured in polynomial mode, implements pre-distortion process to the digital signals which have undergone signal pre-process; the estimate and uploading to an adaptive digital pre-distortion filter is implemented, based on hybrid algorithm which is the combination of training-sequence-based RLS+LMS algorithm or hybrid algorithm which is the combination of training-sequence-based QRD-RLS+NLMS algorithm. The invention can efficiently reduce the performance degradation of a wideband power amplifier caused by memory effect, improve the projecting performance of a base station system, and improve the linearity and the efficiency of the wideband power amplifier.

Disclosed herein are a composite light-emitting material, which includes two or more light-emitting materials selected from an inorganic phosphor, a semiconductor nanocrystal and an organic dye in which the surfaces of the two or more light-emitting materials are coated; and a light-emitting device comprising the same, so as to improve the luminous efficiency and lifetime.

A multi-channel and multi-carrier Digital Predistortion writing machine of wideband CDMA base station system includes the feedback signal processing channels and at least one multiplexing signal processing channels of multi-carrier base band, of which, each includes the digital base-band peak-clipping frequency processor, digital predistortion processing module, high-intermediate frequency output module and filter, radio frequency access and high power amplifier. The feedback signal processing channel includes the RF feedback channel and A / D converter. The invention uses the base band peak-clipping technology, digital predistortion technology and high-intermediate digital IF technology, to reduce the high cost by the use of the linear power amplifier, and can effectively enhance the launch performance and efficiency of the base station system. The invention does not use the feedback channel switching technology to achieve saving the cost of RF link.

The present invention relates to a cellphone antenna medium placode, in particular to a double frequency cellphone antenna medium placode with asymmetric structure left hand material, wherein, the left hand material has double left hand transmission band which is made by introducing the metal resonant ring of non-equal line space. The present invention uses the double left hand band with the asymmetric structure left hand material to realize effective amplification for the evanescent wave in electromagnetic wave in two power frequency sections of low frequency 900MHz and high frequency 1800MHz in cellphone antenna, and the evanescent wave participates in the radiation and receiving work of the antenna to signal, thereby improving radiation efficiency of the cellphone antenna and gains of the cellphone antenna.

A control device for a direct injection engine includes an identifier for judging whether a catalyst is in its unheated state in which its temperature is lower than its activation temperature, an engine temperature state detector for sensing the temperature state of the engine, and a fuel injection controller for controlling fuel injection from the injector. The fuel injection controller controls an injector in such a way that it makes at least two-step split injection including an earlier injection cycle performed during an intake stroke and a later injection cycle performed in a middle portion of a compression stroke or later when the catalyst is in its unheated state, and the later injection cycle is retarded when the catalyst is still in its unheated state but the engine temperature has become higher than a specified temperature compared to a case where the temperature of the engine is equal to or lower than the specified temperature.

The invention discloses a bent piezoelectric-ceramic low-frequency underwater acoustic transducer comprising a front radiation head, a tail mass block, a front curved beam, a rear curved beam, a front piezoelectric crystal pile, a rear piezoelectric crystal pile, a middle opposite-phase piezoelectric crystal pile, a shell and an output cable, wherein the front curved beam, the rear curved beam, the front radiation head and the tail mass block are respectively stuck on two ends of the piezoelectric crystal piles in a certain mode, and thus the piezoelectric crystal piles are in a 'Z'-shaped bending structure of a zigzag rule shape. The shell is combined with a seal ring to realize underwater sealing. The output cable is characterized in that the leads of the piezoelectric crystal piles are connected to an outer driving source by the tail mass block. In the bent piezoelectric-ceramic low-frequency underwater acoustic transducer, the volume space of the transducer is fully utilized, and the sounding power volume of the transducer is increased; and the longitudinal stretching vibration mode of the piezoelectric crystal piles and the bending vibration mode of the curved beams are fully combined to realize the characteristics of low frequency, light weight and small volume of the underwater acoustic transducer to coexist. The bent piezoelectric-ceramic low-frequency underwater acoustic transducer has the advantages of simple structure, low construction cost and wide application, and is convenient to manufacture and convenient to disassemble.

The invention discloses an antenna system of handheld equipment capable of intelligent switching and a switching method. The antenna system comprises a main antenna, a first MIMO antenna and a second MIMO antenna, wherein the main antenna is arranged at the bottom of the handheld equipment and used for the emitting and the main receiving of a plurality of frequency band signals, the first MIMO antenna is used for the second path receiving of low frequency band signals, the second MIMO antenna is arranged at the bottom of the handheld equipment and used for the second path receiving of high frequency band signals, and a double-pole double-throw switch used for cross switching is arranged between the second MIMO antenna and the main antenna. The antenna system of handheld equipment capable of intelligently switching and the switching method split a traditional full frequency band MIMO antenna into the first MIMO antenna and the second MIMO antenna, the first MIMO antenna is arranged at the top of the handheld equipment, the second MIMO antenna is arranged at the bottom of the handheld equipment, and the second MIMO antenna can be intelligently switched with an original main antenna at the bottom of the handheld equipment. Through the antenna system of handheld equipment capable of intelligently switching and the switching method, the design difficulty of the antenna can be reduced, the high frequency band emitting performance of a mobile is improved, and the problem that when the high frequency band coverage is poor, the uplink capacity is insufficient in handheld state is solved.

The invention discloses a field emission electron source and a preparation method of a carbon nanotube graphene composite structure thereof. The field emission electron source comprises a conductive substrate, a graphene film layer and a carbon nanotube array which is directionally perpendicular to the graphene film layer, wherein the graphene film layer is adhered onto the conductive substrate, and one end of each carbon nanotube in the carbon nanotube array is connected with the graphene film layer to form an integrated structure. The emission capacity and stability of the carbon nanotube array field emission electron source are greatly improved, so that the electron source obtains highly efficient and stable emission current, and can bear extremely high emission current density.

The invention discloses a carbon nano fiber / carbon nanotube heterogenous nano array capable of being used for a field electronic emitter and a preparation method thereof. The preparation method mainly comprises the following steps: (1) taking a silicon single-crystal chip or a glass sheet or a ceramic chip, and the like as a substrate; (2) utilizing magnetic filtration vacuum vapor arc plasma deposition technology or magnetron sputtering technology to deposit a catalyst film on the substrate; (3) performing high-temperature heat treatment on the catalyst film in an ammonia gas reaction chamber; (4) introducing working mixture taking hydrogen as carrier gas and acetylene as reaction gas at high temperature, and synthesizing a directional carbon nanotube array on the substrate subjected to heat treatment; (5) adopting an energy-carrying ion beam or a plasma to process the carbon nanotube, and forming the carbon nano fiber / carbon nanotube heterogenous nano array; and (6) using the carbon nano fiber / carbon nanotube heterogenous nano array to process the field electronic emitter.

The invention discloses an asymmetrical high speed and low power consumption transceiver, which comprises a duplexer (10), an envelope detector (11), a demodulator (12), a digital processor (13), a power amplifier (14), a phase-locked loop frequency synthesizer (15) and a storage (16). On the premise of meeting the requirement of certain sensitivity, the extremely low power consumption wireless receiving function is realized; meanwhile, a transmitter can realize high speed and low power consumption modulation transmission, so that the transceiver can be applied to occasions with ultralow power consumption such as medical wireless implant, medical wireless imaging, wireless sensor networks and the like.

The invention relates to a cold cathode focused X-ray tube, wherein, the tube comprises a cold cathode electron source (14), a focused electrode (7), a vacuum sealed shell body (9), a ray emission window (10), a high-voltage anode target (11) and the like, and is characterized in that the tube also comprises a zinc oxide emission layer (5) attached to the cold cathode electron source (14). In the invention, based on a plane grid electrode structure, the electron source is prepared on the surface of a glass substrate (6) in a silk screen printing manner; the high-voltage anode target (11) is fixed right above the electron source; the electrode is arranged in a ceramic vacuum shell body and connected with an external power supply by electrode leads. The ceramic shell body adopts a segmented sealing method; and a metal focused electrode (7) is arranged above the cold cathode electron source (14), and insulation and sealing with ceramics are carried out to the focused electrodes. The focused electrodes can greatly condense electron beams bombarded on the surface of the anode target so as to realize X-ray emission with high resolution factor.

Optoelectronic devices and methods for their fabrication having enhanced and controllable rates of the radiative relaxation of triplet light emitters are provided exemplified by organic light emitting devices based on phosphorescent materials with enhanced emission properties. Acceleration of the radiative processes is achieved by the interaction of the light emitting species with surface plasmon resonances in the vicinity of metal surfaces. Non-radiative Förster-type processes are efficiently suppressed by introducing a transparent dielectric or molecular layer between the metal surface and the chromophore. For materials with low emission oscillator strengths (such as triplet emitters), the optimal separation distance from the metal surface is determined, thus suppressing energy transfer and achieving a significant acceleration of the emission rate.

This invention provides a process for improving the field emission of an electron field emitter comprised of an acicular emitting substance such as acicular carbon, an acicular semiconductor, an acicular metal or a mixture thereof, comprising applying a force to the surface of the electron field emitter wherein the force results in the removal of a portion of the electron field emitter thereby forming a new surface of the electron field emitter.

The transfer case reduction gearset is often never used for its original intended function, that is, to provide an additional speed reduction (torque amplification) ratio for the powertrain. This concept allows for the increased use of the transfer case gearset components to work in concert with the automatic transmission to increase its ratio spread. This increase in ratio spread will result in improved launch performance for the vehicle by steepening the effective first gear ratio of the automatic transmission. The increase in ratio spread may also provide for reductions in numerical axle ratio of the vehicle thereby improving the fuel economy during normal highway operation. The present invention focuses on a method of shifting the transmission of the vehicle in accordance with the invention which includes providing a transmission connected to a vehicle engine having a predetermined number of gear ratios which are selectable.

The invention provides a multichannel radio-frequency signal control system. The system comprises a multichannel radio-frequency signal emission unit, a power signal receiving unit and a digital signal processing unit, wherein the multichannel radio-frequency signal emission unit is used for providing first radio-frequency signals of multiple channels; the power signal receiving unit is used for receiving a first power signal fed back by the first radio-frequency signal of any channel in the multichannel radio-frequency signal emission unit; the digital signal processing unit is connected with the multichannel radio-frequency signal emission unit and the power signal receiving unit, is used for processing to-be-emitted radio-frequency signals of the multiple channels and transmitting a first base band signal to the multichannel radio-frequency signal emission unit, receives and processes a second power signal received by the power signal receiving unit and then transmits a third power signal to peripheral equipment. According to the multichannel radio-frequency signal control system, the simulation intermediate frequency process is omitted, the signal performance is improved, the modular design is adopted, the number of the channels can be configured flexibly, and the system can meet requirements of magnetic resonance equipment with various field intensities.

The invention discloses a radiation cooling passive cooling fabric and a preparation method thereof, and belongs to the technical field of textile. The radiation cooling passive cooling fabric sequentially comprises an infrared high emission top layer, a sunlight low absorption fabric layer and a sunlight high reflection bottom layer from top to bottom; the infrared high emission top layer is 0.5-0.9 in emissivity on infrared light with the wavelength of 8-13[mu]m; the sunlight low absorption fabric layer is 0.3-0.9 in sunlight emissivity; the sunlight high reflection bottom layer is 0.5-0.9 in sunlight emissivity; and the sunlight low absorption fabric layer is woven by fibers, wherein the cross sections of the fibers are triangular. According to the fabric, through synergic matching of three layers, a high infrared emissivity and strong sunlight reflectivity effect is realized in daytime, and the radiation cooling performance of the material in daytime is improved.

The invention relates to a rhenium tungsten based cathode material and a preparation method thereof and belongs to the technical field of a refractory metal thermal cathode material. BaO, CaO and Al2O3 are loaded in pores of a porous rhenium tungsten base; the rhenium tungsten base is formed by coating tungsten grains by rhenium. The preparation method comprises the following steps: dissolving ammonium perrhenate in water, thereby preparing into a solution; adding tungsten powder into the ammonium perrhenate solution and stirring; drying; resolving and reducing in two steps under the hydrogen atmosphere, thereby obtaining rhenium tungsten powder; and pressing and sintering the rhenium tungsten powder under the hydrogen atmosphere, thereby obtaining a rhenium tungsten base and steeping into a molten barium aluminate calcium salt. The preparation method provided by the invention has the advantages that the preparation process is simple, the introduction of impurity element during the preparation process is avoided, the repeatability is strong, the prepared cathode material is excellent in emitting property, and the ion bombardment resistance of a traditional barium tungsten cathode is enhanced.

The invention relates to an air-coupled capacitive micromachining ultrasonic transducer, a preparation method and application. A transducer array comprises 16 array elements; each array element is formed by multiple sensing units; each sensing unit is structurally formed by an upper electrode 1, a vibrating diaphragm 2, a cavity 3 and a base 5 sequentially from top to bottom; and each base is usedas a lower electrode. The working frequency of the designed transducer is 100kHz to 2MHz. The transducer array is manufactured based on an SOI bonding process; each vibrating diaphragm is made of monocrystalline silicon; each upper electrode is gold or aluminum; an insulating layer 4 is silicon dioxide or silicon nitride; and the array elements of the transducer are divided through etching the low-resistance-silicon bases to form grooves, so that the array with the multiple array elements is formed. According to the air-coupled ultrasonic transducer, an ultrasonic wave in a metal plate or a composite plate is excited through an air coupling manner and is used for nondestructively detecting internal defects of the plate. The transducer is matched with a phased array system, and pulse drivesignals of the array elements are delay-controlled, so that the phase-controlled deflection and the focusing of an acoustic beam are adjusted, and the freedom degree of detecting is increased.

The invention discloses an uplink precoding emitting method and device. When a base station judges that UE (User Equipment) is allowed to automatically up precode, and informs the UE of carrying out uplink precoding emission by adopting an automatic uplink precoding mode. By adopting the invention, the UE can automatically carry out uplink precoding emission, the problem that a codebook selected by an eNode B can not be matched with a channel when uplink sending is carried by adopting a precoding matrix sent by an eNode B simply in the traditional uplink is overcome, therefore, the channel can be well matched, the emission property of an uplink is improved, and system packet error rate is lowered; and if a non-codebook precoding method is adopted, quantization errors of the codebook can be further overcome, the channel is accurately matched, and the property of the uplink is improved.

A hydraulic tensioner applies appropriate tension to an endless power transmitting belt. The hydraulic tensioner includes a plunger body, an oil supply path, a check valve, a relief valve, a pressure maintaining valve interposed in a relief path and a pressure accommodating hole. The hydraulic tensioner is configured such that a path that is branched from the oil supply path for operating the pressure maintaining valve is formed independently of a supply path to the check valve.

The invention discloses a dip-coated barium-tungsten cathode for traveling-wave tubes and a preparation method thereof. The dip-coated barium-tungsten cathode comprises a cathode drum, a cathode spongy body positioned inside the cathode drum. The invention is characterized in that the cathode spongy body is laminated by a tungsten spongy body and a tungsten-rhenium spongy body, wherein the tungsten-rhenium spongy body is coated with a noble metal film on the surface. With the above structure and preparation method, compared with the prior art, the cathode spongy body is a two-layered cathode spongy body laminated by the tungsten spongy body and the tungsten-rhenium spongy body, to replace the single-layer alloy substrate with uniform porosity in the prior art; the consumption of the noble metal Re is reduced; the porosity of the tungsten spongy body is increased; the storage level of cathode salts is increased; and the preferable proportion of the cathode salts allows both the emission behavior and the stability of salts better. With the noble metal Re coating, the cost of target materials is reduced. The consumption of noble metal is greatly reduced while ensuring the maximal emission and long service life of alloy substrate film-coated cathodes. The storage quantity of cathode salts is increased and the service life of cathode is prolonged.

The invention discloses a functional assembly and a mobile terminal. The functional assembly comprises a circuit board, an antenna feed part and a decorative ring fixed on the circuit board; the antenna feed part is used for transmitting and receiving an electromagnetic signal; and the decorative ring is electrically connected with the antenna feed part and the circuit board. By enabling the decorative ring to be electrically connected to the antenna feed part, the decorative ring can be used as a radiator of the antenna, so that the radiation area of the radiator of the antenna is enlarged, and interference of the decorative ring to electromagnetic signal radiation can be avoided; the decorative ring is arranged on the shell of the mobile terminal and exposed outside the mobile terminal,and the decorative ring is used as the radiator of the antenna feed part, so that interference from other components in the mobile terminal to the decorative ring can be reduced; the electromagnetic signal receiving and transmitting capabilities of the mobile terminal are reinforced without an additional structure, so that the communication capability of the mobile terminal can be further improved; and the functions and utilization rate of the decorative ring in the mobile terminal also can be improved.

β-Sialon comprising Eu2+ that is present in a solid solution form in P-sialon represented by Si6-zAlzOzN μm [wherein z is 0.3-1.5], which shows, when excited with light of 450 nm in wavelength, a peak wavelength of fluorescent spectrum of 545-560 nm, a half-value breadth of 55 nm or greater, and an external quantum efficiency of 45% or greater. The p-sialon can be produced by blending at least one kind of oxide selected from aluminum oxide and silicon oxide with silicon nitride and aluminum nitride in such a manner as to give z of 0.3-1.5, further adding thereto a europium compound and a β-sialon powder having an average particle diameter of 5 μm or greater and an average degree of circularity of 0.7 or greater, each in a definite amount, and baking the mixture.

The invention discloses a method for preparing a film system with a secondary electron emission function, belonging to the field of functional film preparation. The method comprises the following steps of: (1) cleaning a vacuum chamber; (2) cleaning a substrate; (3) loading the substrate; (4) vacuumizing the vacuum chamber; (5) cleaning a target material by using plasma; and (6) depositing secondary electron emission films. According to the method, the traditional oxidation process is replaced with a preparation method that multiple layers of composite functional films are deposited, so that the prepared film has the advantages of good compactness, strong adhesion, high secondary electron emission rate and the like.