31results about How to "Improve performance loss" patented technology

The present invention provides relates to an exhaust gas purifying catalyst. The objective of the invention is to provide the exhaust gas purifying catalyst through which exhaust gas purifying performance, OSC performance, and pressure loss are optimized. The catalyst has a substrate and two or more catalyst coating layers formed on the substrate, wherein the uppermost catalyst coating layer comprises an OSC material having a pyrochlore-type structure, an OSC material having a faster oxygen storage-release rate than that of the OSC material having a pyrochlore-type structure, and a precious metal catalyst containing at least Rh. In the uppermost catalyst coating layer, the content of the OSC material having a pyrochlore-type structure is 30 g / L to 50 g / L, based on the volume of the substrate, and the content of the OSC material having a faster oxygen storage-release rate than that of the OSC material having a pyrochlore-type structure is 36 g / L to 72 g / L, based on the volume of the substrate.

The present invention is a demodulation method and system based on the dynamic threshold judgment of QPSK modulation that the frame synchronization code is implicit in the information code, which is different from the fixed format of the synchronization symbol plus the data symbol of the traditional data frame. Sequencing is implicit in the modulation and demodulation process. When modulating at the sending end, the amplitude of the signal is modulated by using the synchronization code sequence, so that the synchronization code sequence is implied in the information sequence. When demodulating at the receiving end, the signal corresponding to the synchronization code sequence is extracted from the received signal, and the method of correlation detection can be used to realize the frame synchronization of the system. After the synchronization is achieved, the received signal is coherently demodulated, and a dynamic threshold judgment The method makes a judgment and restores the original information bits. The transmission rate of the system is improved by embedding the frame synchronization code in the modulation, and the dynamic threshold judgment is used in the demodulation to improve the bit error rate performance of the demodulation.

The invention provides a method for improving the quality of a broadcasting service in a mobile communication network, which is invented to solve the problem that the quality of the broadcasting service in the prior cellular mobile communication network cannot be guaranteed. The method comprises the following steps: testing the received power strength of a broadcasting service channel in a service coverage region, and determining the location of a region in which the received power strength of the broadcasting service channel does not reach an expected value; if the region not reaching the expected value is positioned on the edge of the service region, superposing a beamformed broadcasting service channel with a different frequency or a different time slot which bears the same service on the basis of the prior signals in the service coverage region; and if the region not reaching the expected value is not positioned on the edge of the service region, performing joint adjustment of thepower of the broadcasting service channels of a plurality of cells in the service coverage region. The method can select different adjusting modes according to the location characteristics of the region not reaching the standard and improves broadcasting service signals by power compensation or multi-element antenna beamforming.

The invention discloses a preparation method of conductive glass fibers with cuprous sulfide as a conductive layer and belongs to the field of preparation of composite conductive fibers. According to the method, firstly, glass fibers which are washed clean are subjected to hydroxylation treatment in a hydrochloric acid solution and soaked in a silk fibroin aqueous solution, crosslinking is performed through glutaraldehyde, and accordingly, firm silk fibroin layers are formed on surfaces of the glass fibers; finally, copper sulfate pentahydrate and sodium thiosulfate are taken as raw materials and subjected to a chemical reaction, and then cuprous sulfide is produced on surfaces of the glass fibers. With the adoption of the method, adsorption of metal sulfides on the surfaces of the glass fibers is effectively improved, the interface adhesion is high, and the method has the advantages that the preparation process condition is easy to guarantee, the cost is saved, the conductive performance of the fibers is excellent and the like.

The present invention relates to a catalyst for exhaust gas purification. [Problem] An object of the present invention is to provide a catalyst for exhaust gas purification which optimizes OSC performance and pressure loss. [Solution] A catalyst for exhaust gas purification, which has a substrate and two or more catalyst coatings formed on the substrate, wherein the uppermost catalyst coating contains: an OSC material having a pyrochlore structure, oxygen An OSC material whose absorption and emission rate is faster than that of an OSC material having a pyrochlore structure, and a noble metal catalyst containing at least Rh; The material capacity is 30g / L-50g / L, and the content of the OSC material whose oxygen absorption and release rate is faster than the OSC material having a pyrochlore structure is 36g / L-72g / L relative to the above-mentioned base material capacity.

The invention provides a preparation method of cuprous sulfide / carboxylation chitosan / glass fiber composite conductive fiber. An alkali-free glass fiber is immersed in an aqueous hydrochloric acid solution, and is sufficiently rinsed with water and dried to obtain a hydroxylated glass fiber after soaking; the hydroxylated glass fiber is immersed in a carboxylation chitosan aqueous solution, and then is taken out after soaking and the taken hydroxylated glass fiber is immersed into a glutaraldehyde solution, is taken out and is sufficiently rinsed with water and dried to obtain carboxylation chitosan surface modified glass fiber; the carboxylation chitosan surface modified glass fiber is put into a copper sulfate pentahydrate aqueous solution, and is added into a sodium thiosulfate aqueous solution after soaking, then the soaked carboxylation chitosan surface modified glass fiber is taken out and rinsed with water and dried after reaction to obtain the cuprous sulfide / carboxylation chitosan / glass fiber composite conductive fiber. The process is used for preparing the conductive glass fiber, the equipment investment expense is low, the operation is simple, the reaction condition is mild, the applicability is strong, the treatment effect is good, the fiber performance loss is low, the fiber quality is reliable, the environment pollution is alleviated and the method is suitable for industrial production.

The invention discloses a method for removing valence electrons of graphene. The method includes the following steps that oxidized graphene and a valence electron remover are sequentially added into a solvent, the mixture is dispersed and mixed to be uniform through ultrasonic treatment, the solvent is removed, and an oxidized graphene / valence electron remover mixture is obtained; the oxidized graphene / valence electron remover mixture is put in mixed gas flow of inert gas and carbon dioxide / water steam for activation, the gas flow is switched into a boron-bearing gas-state compound, heat is preserved for 5-24 hours at the temperature of 150-230 DEG C, the material is cooled to room temperature, and the graphene with the valence electrons removed is obtained. The valence electrons between layers of the graphene are removed through catalysis of doping elements, the intermolecular force between the layers of the graphene is reduced, stacking and compounding between the slice layers of the graphene are avoided accordingly, the characteristic that the graphene attract is changed, the problem that the graphene is clustered in oil is effectively solved, and the situation that the performance of graphene is lost due to stacking and compounding of the slice layers in the using process is relieved.

The invention discloses a receiving performance optimization method and device for an optical communication system, wherein the method comprises the steps of: demodulating and analyzing the signals received by a receiver to obtain information of an error code; regulating the working point of the receiver based on the information of the error; and carrying out feedback control to the receiver. In the method disclosed by the invention, the receiver is controlled by the information relevant to the error code; the information of error code primarily used for correcting and alarming is jointed to the control to the receiver of the optical communication system, so that the transmission performance of the optical communication system can be greatly improved.

The invention provides an OFDM-MFSK underwater acoustic communication technology based on packet signal to noise ratio (SNR) confidence coefficient. A transmitting end performs two-diversity modulation on the information and adds chirp signals at the head and the tail of one frame of data; a receiving end performs detection on a frame preamble signal to finish the data interception and the doppler factor estimation, and performs the doppler compensation on the received data; the demodulation is performed on each data symbol, and the diversity signals are combined according to a combining way of the packet SNR confidence coefficient; and finally the demodulation is performed on the data after the diversity combination. By using the frequency diversity technology, the performance loss caused by the channel serious frequency selectivity influence of the OFDM-MFSK underwater acoustic communication system is effectively compensated, and the SNR of the combined signal is improved by proposing the diversity signal combination way based on the packet SNR confidence coefficient.

The invention discloses a method for preparing cuprous sulfide / polyethyleneimine / fiberglass composite conductive fiber. The method comprises the steps of conducting surface treatment on fiberglass with vacuum plasmas; immersing the plasma treated fiberglass in a polyethyleneimine aqueous solution, and then conducting rinsing with water and drying to obtain fiberglass with surface modified by polyethyleneimine; placing the fiberglass with surface modified by polyethyleneimine in a copper sulfate pentahydrate aqueous solution, adding a sodium thiosulfate aqueous solution after soaking, taking fiber out after reaction, and conducting rinsing with water and drying to obtain the cuprous sulfide / fiberglass composite conductive fiber. When the method is used for preparing conductive fiberglass, equipment investment is low, operation is easy, reaction conditions are mild, adaptability is high, treatment effect is good, fiber performance loss is low, quality is reliable, and environment pollution can be reduced. The method is suitable for industrial production.

The invention discloses a method for preparing electrically conductive glass fibers by adopting plasma-assisted preprocessing. The method comprises the following steps: firstly, cleaned glass fibers are subjected to vacuum plasma processing, and surface hydroxylation of the glass fibers is realized; then the glass fibers are soaked in a silk fibroin solution and subjected to crosslinking through glutaraldehyde, so that a firm silk fibroin layer is formed on the surfaces of the glass fibers; finally, copper sulfate pentahydrate and sodium thiosulfate are taken as raw materials to produce copper(I) sulfide on the surfaces of the glass fibers with a chemical reaction method. The method has the advantages that adsorption of metal sulfide on the surfaces of the glass fibers is improved effectively, the interfacial adhesion is strong, preparation process conditions are easy to implement, the cost is saved, the electrical conductivity of the fibers are excellent and the like.