79results about How to "Lower peak temperature" patented technology

The invention relates to the technical field of soldering pastes, in particular to a halogen-free tin-bismuth-copper soldering paste and a preparation method thereof. A soldering flux of the halogen-free tin-bismuth-copper soldering paste consists of the following components in percentage by weight: 20 to 40 percent of polymerized rosin, 1 to 6 percent of rosin amine, 4 to 8 percent of thixotropic agent, 5 to 10 percent of organic acid, 5 to 10 percent of organic amine, 1 to 5 percent of antioxidant, 0.5 to 3 percent of surfactant and an organic solvent. The halogen-free tin-bismuth-copper soldering paste is mainly characterized by adopting the organic acid and the organic amine serving as activating agents and comprising no halogens at all, so not only the solderability is not reduced, but also the expansion rate and the insulation resistance value of the soldering paste are improved, and simultaneously the corrosivity of residues after soldering to a base material is reduced and the service life of the soldering paste is prolonged; and particularly, the peak temperature of the soldering paste during soldering is lower in favor of reducing the thermal damages to electronic components.

The invention discloses a nozzle of a combustion chamber of a miniature gas turbine, relates to the gas turbine technology, and in particular to a small size fluid fuel nozzle used in a combustion chamber of a 100 kW level miniature gas turbine. The nozzle consists of three parts which are a fuel oil passage, a fuel air passage and an air channel at the root of a burner, comprehensively utilizes the advantages of pneumatic nebulization and pressure atomization, and is a combined type high performance pneumatic atomizing nozzle. The nozzle of the invention has the characteristics that: the nozzle adopts a conventional processing method to realize excellent atomization of the fuel in small scale space, so as to meet the requirement for the quality of fuel atomization under a quite wide burden of the combustion chamber of the miniature gas turbine; the nozzle can avoid burnout and overcomes the defect of nozzle blockage caused by high temperature coking of the fuel; meanwhile, the nozzle can make the fuel in the combustion chamber to be combusted more fully and reduce discharge of pollutants such as smoke black and so on.

The invention relates to the technical field of clean gas burning, in particular relates to a gas burner with low NOX, which aims to further reduce the pollutants, especially the generating amount of NOX caused by the gas burner, and simultaneously improves the efficiency of a whole boiler. The gas burner disclosed by the invention integrates the technologies of enhancement of the mixing of gas and combustion air, graded and sectioned burning, burning of thick gas and thin gas, smoke circulation and the like, and can enhance the mixing of the gas and the combustion air so as to achieve the beneficial effects that the burning is reinforced, the peak value temperature of burning flame is reduced, and further the excess air coefficient of the burning is reduced, and the pollutants such as NOX and the like can be reduced to be minimum.

Thermal energy exposed at the outer surface of an information handling system housing is managed by spreading the thermal energy across the housing X and Y axes while restricting heat transfer from the housing at the Z axis. For example, a graphene outer surface couples to an aerogel substrate strengthened by a carbon fiber laminate. The graphene spreads thermal energy that escapes through the housing across the housing outer surface to limit the impact of thermal energy at any particular location, such as proximate to the location of a processor.

The invention relates to an overlap welding method using an ultrathin aluminum-steel compound transition joint. The method comprises the steps of: pre-welding treatment; and a method of welding aluminum first and then welding steel during welding. The patent provides the welding method of welding aluminum first and then welding steel. As the heat conductivity coefficient of aluminum is about 3 times that of iron. Heat dissipation of an aluminum-steel interface is facilitated if aluminum is welded first, and the peak temperature of the aluminum-steel interface in the welding process is reduced, so that continuous welding is guaranteed, and meanwhile, the aluminum-steel interface of the ultrathin aluminum-steel compound transition joint is not peeled off.

The invention discloses a hierarchical heat driving floor planning and layout method which comprises the following steps of: firstly, arranging a plurality of modules according to a power sequence, and forming a module sequence; secondly, grouping the module sequence from front to back according to an area sum, dividing into a plurality of module layer groups with approximately equal area sum; thirdly, establishing an analysis heat mold for calculating the average temperature of the module groups; fourthly, acquiring a power distribution constraint graph of each module group; and fifthly, sequentially arranging the module groups above a heat dissipating device at the bottom layer according to the power density, the sequence from big to small and the respective power distribution constraint graph. In the method, a three-dimensional layout problem is converted to a two-dimensional layout problem, thereby avoiding putting a high-power density device in a pile of vertical regions, realizing power density balanced distribution in vertical and horizontal directions, efficiently reducing the hot spot amount and optimizing the chip area and the interconnecting wire length.

The present disclosure concerns a lighting device (100) comprising a light source (1) and a light guide plate (2). The light guide plate (2) is disposed at a distance (D1) from the emitter surface (1a) with an air gap (3) therebetween. A side reflector (4) surrounds the emitter surface (1a) of the light source and bounds the gap (3) between the emitter surface (1a) and the light entry surface (2a). The side reflector (4) comprises a tapered reflection surface (4a) adjacent the emitter surface (1a) and facing the light entry surface (2a). The tapered reflection surface (4a) is disposed at a tapering angle (β) towards the light entry surface (2a). The tapering angle (β) is configured such that any light emitted by the emitter surface (1a) within the opening angle (Φ) of the light source (1) is not reflected by the reflection surface (4a) before being received for the first time by the light entry surface (2a).

The invention discloses a thermal-sensing and low-energy consumption task scheduling method oriented to a heterogeneous MPSoC system. The method comprises the following steps: converting a heterogeneous multi-processor supporting multiple frequencies into a virtual multi-processor model only supporting a fixed frequency; distributing the task with the dependency relation to the virtual processor by using a heuristic algorithm; computing peak temperature of the system under the current task distribution; computing the accomplishment time of the task under the current task distribution; verifying this task distribution satisfies a constraint condition of the time and the task dependency relation; and updating a undistributed task queue, the task queue distributed to each virtual processor, and the task execution time of each virtual processor. Under the constraint of the task expiration deadline, the task priority and the chip peak temperature, the system energy consumption is optimizedthrough the thermal-sensing energy-saving scheduling algorithm; the algorithm determines the task distributed to each processor and the working efficiency of each task, thereby effectively computing the low energy-consumption task scheduling solution.

The invention relates to a laser-electric arc two-heat source weak coupling welding method for high-nitrogen steel. Firstly, energy density of laser beams is reduced by means of an optical regulationand control technology; then, the energy density of a composite heat source is reduced by means of two-heat source weak coupling effect; and more importantly, the weak coupling effect is capable of changing the flowing speed and direction of a molten pool and reducing the peak temperature of the molten pool, so that nitrogen precipitation of base metal is reduced, reabsorption of molten pool liquid metal on precipitated nitrogen is improved, discharge of redundant nitrogen is accelerated, and pore-free welding seams are formed finally. The comprehensive mechanical property of splice is improved, and the problems that the welding pores of the high-nitrogen steel are difficult to inhibit and the consistency of the performance of the splice is poor in the prior art are solved. The method hasthe advantages of high welding speed and good welding seam quality and the production efficiency and product quality are improved; and the problems of multiple welding seam pores, poor comprehensive performance and complex welding process in the related art are solved, the product quality is improved, the production cost is reduced, the welding process is simple, and high automation degree is achieved.

The invention provides a three-dimensional composite oxide catalyst for removing NO and coal smoke particles simultaneously and a preparation method and application thereof.The preparation method comprises the steps that under the stirring condition, a cerium source, an iron source and a zirconium source are dissolved in an organic solvent, the mixture is stirred to be uniform at the temperature of 20 DEG C to 45 DEG C, and a precursor solution is formed; a template agent is weighed and added to the precursor solution to be dipped, and then suction filtration and drying are carried out; solids obtained through drying are heated in a heating furnace for the first time and heat preservation is carried out, and then the solids obtained through drying are heated for the second time and heat preservation is carried out, and the three-dimensional composite oxide catalyst is obtained.The three-dimensional composite oxide catalyst is a cerium, iron and zirconium composite oxide, and the composition of the catalyst is Ce0.9-xFexZr0.1O2, wherein x ranges from 0.1 to 0.4.According to the catalyst, the temperature at which the coal smoke particles are combusted to be converted into CO2 and the temperature for NO conversion can be reduced to the same range, meanwhile, the NO conversion rate is increased, and the activity of catalytic coal smoke combustion is improved.

A quench protection apparatus includes a number N of superconducting coils and a heater matrix. The number N of superconducting coils are electrically coupled in series. The heater matrix module includes the number N of heater units. The number N of heater units is electrically coupled in parallel with the number N of superconducting coils respectively. A number M of the heater units each includes at least the number N of heaters. Each superconducting coil is thermally coupled with at least one heater of each of the number M of the heater units. The number of N-M of the heater units each includes at least one heater. Each of the number M of superconducting coils correspondingly coupled with the number M of the heater units is thermally coupled with at least one heater of each of the number N-M of the heater units. A superconducting magnet system protected by above quench protection apparatus is also provided.

A method of constraining a Safe Operating Area (SOA) locus for a power semiconductor device during operation of the power semiconductor device placed between a power source and a load, the method including: taking a voltage measurement across the load (VLOAD); selecting a scalar for scaling the voltage measurement taken across the load (VLOAD); and constructing a control voltage for controlling the power semiconductor device with a control circuit according to the voltage measurement taken across the load (VLOAD) multiplied by the scalar so as to constrain an output voltage of the power semiconductor. <filename>

The invention provides a method for preparing ultrathin crystalline silicon double-sided solar cell. The method comprises steps of: firstly thinning a polycrystalline silicon substrate to 90-120[mu]mat 18-25 degrees centigrade for 2000-2300s by using a mixed solution of HF, H2O2 and an additive, wherein a textured structure is formed on the surface of the substrate during the thinning process; preparing a PN junction by roll diffusion, and using ultrasonic atomization of phosphoric acid, thereby being nontoxic and nonpolluting, and achieving a uniform diffusion junction; and disposing siliconnitride antireflection layers on the front and back sides of the substrate; finally forming finger electrodes on the front and back sides by a silk-screen printing and sintering process. The method is suitable for the production technology of polycrystalline silicon 90-120[mu]m thick. Compared with a method for preparing a conventional polycrystalline silicon cell 180[mu]m thick, the method can reduce the thickness of the cell under the premise of ensuring a fragmentation rate, ensures battery efficiency, is simple in process, and low in cost. The method also solves the problem that the thincell is likely to be bent and is fragile, and can be industrialized by experimental verification.

The invention relates to a power semiconductor technology, in particular to a low-junction-temperature and high-voltage-resistance GaN heterojunction field effect transistor. According to the low-junction-temperature and high-voltage-resistance GaN heterojunction field effect transistor provided by the invention, an AlN region is mainly inserted into a barrier layer to reduce a channel peak valveelectric field, so that the aims of increasing the voltage resistance and reducing the heat dissipation are realized. Furthermore, AlN with a good heat-conducting property is used as a passivation layer of a device, so that the current collapse is favorably inhibited and the effect of accelerating heat dissipation is also realized. The low-junction-temperature and high-voltage-resistance GaN heterojunction field effect transistor has the excellent effects that reverse voltage resistance of the device is improved, output properties of the device are improved and the channel temperature of the device is reduced, so that dangers caused by the current collapse and a self-heating effect are inhibited. The invention is especially applicable to the GaN heterojunction field effect transistor witha high-voltage-resistance capability and low channel temperature.

The invention discloses a reflow soldering method for improving device thermal expansion deformation. The reflow soldering method comprises the following steps: an SMT steel net is prepared, solder paste is printed for a PCB through the SMT steel net, and the PCB printed with the solder paste is sent into a placement machine to be subjected to SMT placement; the PCB subjected to placement is put into a reflow furnace, and heated nitrogen is introduced into the reflow furnace; primary heating is conducted, and the heating speed is smaller than or equal to 2 DEG C/s; heat preservation is conducted, the rotating speed of a fan at an upper air opening is increased, and the rotating speed of a fan at a lower air opening keeps unchanged; secondary heating is conducted, and the heating speed is smaller than or equal to 2 DEG C/s; reflow soldering is conducted; temperature decreasing for cooling is conducted, and soldering is completed; and subsequent detecting is conducted. The peak value temperature of reflow soldering can be lowered, thus the process window index (PWI) is increased, the good soldering hot melting effect is generated, the temperature difference between components and thePCB is reduced, and the problems of pseudo soldering and deformation caused by the too large temperature difference are avoided.

The invention discloses a welding method for a cold plate component. The cold plate component comprises a cold plate substrate, a cold plate cover, a hot bent pipe, and thermal conductive fingers. Thewelding method comprises the following steps of: step (1). nickel plating, to be specific, plating the interior of a first groove of the cold plate substrate, the interior of a second groove of the cold plate cover, the middle position of the hot bent pipe, each end of the hot bent pipe and each thermal conduction finger with nickel to form nickel layers; step (2). applying tin, to be specific, applying a layer of solder paste to each of the nickel layers in step (1); step (3). assembling, to be specific, inserting the hot bent pipe into the first groove of the cold plate substrate and the second groove of the cold plate cover, respectively embedding the two ends of the hot bent pipe into one thermal conductive finger, thereby forming a cold plate assembly; and step (4). heating, to be specific, putting the cold plate assembly in step 3) into a reflow oven for reflow soldering. The cold plate component is subjected to nickel plating and tin applying surface treatment, so that metal parts on the cold plate component can be soldered by adopting low temperature tin-lead solder to ensure the thermal conductivity and welding quality of the cold plate component.

The invention relates to a CAN bus-based medical X-ray high voltage generator control system, which comprises a console MCU module, a high voltage generator and a bulb tube connected in sequence, wherein the high voltage generator comprises a power interface module, a rotary anode driving module, a high voltage loop control module, a large-small focal filament power module, an AEC shooting control module, an IBS perspective control module, a high voltage inverter and a transformer; the console MCU module, the power interface module, the rotary anode driving module, the high voltage loop control module, the large-small focal filament power module, the AEC shooting control module and the IBS perspective control module are mutually connected via the CAN bus; and the high voltage inverter and the transformer are respectively connected with the high voltage loop control module and the bulb tube. Compared with the prior art, the system has the advantages of flexibility, reliability, low cost, good system performance and the like.