391results 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.

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.

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 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 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 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.

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.

β-Sialon comprising Eu²⁺ that is present in a solid solution form in P-sialon represented by Si_6-zAl_zO_zN 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.