Abstract: Disclosed is an offline/online signature system including a key distribution center (KDC) and a signature end, wherein the KDC includes a key generating module, an offline signature module, and a verification module; and the signature end includes an online signature module and a verification module. The key generating module generates a temporary signature required for online signature, and transmits the result to a sensor node for storage. The online signature module generates a signature for a specific message; and the verification module includes a processor and a public key transformation component, wherein the processor transmits the signature to the public key transformation component and determines whether the signature is valid.

Abstract: Provided are a polymer containing S,S-dioxide-dibenzothiophene in backbone chain with content-adjustable triarylamine end groups, and a preparation method and an application thereof. Triarylamines hole-transport small molecules are introduced into the polymer end group, and a content of the triarylamine end groups can be adjusted by controlling a polymer molecular weight, so that the polymer has better electron-transport and hole-transport capabilities, and charge carrier transport can be balanced, so that more exciton recombination takes place effectively, thus improving the luminous efficiency and stability of the polymer. The polymer is prepared by a Suzuki polymerization reaction and does not require synthesis of new monomers. The polymer material is used for preparing highly effective and stable monolayer devices, and is dissolved directly in an organic solvent, then spin-coated, ink-jet printed, or printed to form a film.

Abstract: Disclosed are an AlGaN/GaN heterojunction HEMT device compatible with a Si-CMOS process and a manufacturing method therefor. The device comprises: an AlGaN/GaN heterojunction epitaxial layer, a passivation layer, a gate dielectric layer, a gold-free gate electrode and gold-free source and drain electrodes. The AlGaN/GaN heterojunction epitaxial layer comprises a substrate, a nitride nucleating layer, a nitride buffer layer, a GaN channel layer, an AlGaN intrinsic barrier layer and an AlGaN heavily-doped layer from bottom to top in sequence; the AlGaN heavily-doped layer generates charges by an ionized donor so as to compensate for a surface acceptor level of a semiconductor, thus suppressing a current collapse; and ohmic contact with an electrode is formed by low-temperature annealing; and the gold-free electrode prevents Au from polluting a Si-CMOS process line.

Abstract: A manufacturing technique of ultra-wideband high gain optical fibers and devices is disclosed, including: (1) manufacturing a gain fiber, which is a composite structural optical fiber, having a core composed of a plurality of sets of sector structures distributed symmetrically or a plurality of concentric ring structures. The core is composed of at least two kinds of rare-earth-ion-doped glass, and luminescence centers are located in different sector or ring structure regions; and (2) constructing a fiber laser: using the gain fiber, selectively exciting rare earth ions in different regions in the core by controlling a shape of pump light spot, and combining with fiber grating pairs to realize a tunable laser output. The present disclosure can manufacture gain fibers with high-gain and ultra-wideband characteristics by combining the design of the fiber structure and the control of the light field of the pump light.

Abstract: Provided is a matrix type double parallel capillary tube shock absorber with a variable system natural frequency, wherein on a pipeline between oil supply ports of an upper oil compartment (14) and a lower oil compartment (16), a capillary tube parallel type damping associated section and a capillary tube parallel type system natural frequency associated section are successively connected from top to bottom; the capillary tube parallel type damping associated section comprises four capillary tubes connected in parallel, with each capillary tube being connected in series with a solenoid valve so as to control the operation of the capillary tube; the capillary tube parallel type system natural frequency associated section comprises four capillary tubes connected in parallel, and each of the four capillary tubes is connected in series with a solenoid valve so as to control the operation of the capillary tube; the diameter of the smallest capillary tube of the frequency adjustment section is much larger than the

Abstract: A filtering antenna element and a dual-band filtering antenna array using filtering antenna elements for mutual coupling suppression have been disclosed. The filtering antenna element comprises a feeding element, a sub-substrate, a sup-substrate and an air gap between the sub-substrate and the sup-substrate. A stacked patch is fabricated on a top surface of the sub-substrate, a driven patch and a ground plane are fabricated on a top surface and a bottom surface of the sub-substrate. An asymmetric E-slot is arranged on the driven patch and a shorting pin is inserted into the sub-substrate for generating radiation nulls in stopbands. The dual-band filtering antenna array is compact and needs no feeding network with an isolation of 35 dB, and is suitable for potential base station applications.

Abstract: The present invention provides a double freeform-surface lens with uniform color temperature including an incident free surface, an emergent freeform-surface and a side connecting face. The side connecting face is a side wall connecting the incident freeform-surface and the emergent freeform-surface. Aiming at impacts of using the single lens on color temperature upon LED light distribution, the double freeform-surface lens is designed, which is fabricated from a transparent optical material. The transparent material is PC or PMMA or optical glass. The double freeform-surface lens is capable of controlling a light distribution angle, and light spots obtained have uniform color temperature.

Abstract: The present invention discloses a saury Maillard peptide with antihyperuricemic activity and its preparation method and application, with the method comprising the following steps: mincing a saury, adding water, heating, agitating, adjusting a pH value to 4.2, separating by centrifugation, and collecting the precipitate; adding water, proteases and amino acids to the precipitate, adjusting a pH value to 7.0, hydrolyzing, adding a reducing sugar to cause a reaction, centrifuging and collecting a supernatant which is saury Maillard peptide; and spray drying the peptide liquid to obtain a dry powder. The method of the present invention realizes the continuous action of enzymolysis and Maillard reaction to prepare the Maillard peptide, not only simplifying the production process, shortening the production cycle, and reducing the production costs, but also significantly enhancing the antihyperuricemic activity of the produced Maillard peptide.

Abstract: An enhancement-mode GaN-based HEMT device on Si substrate and a manufacturing method thereof. The device includes a Si substrate, an AlN nucleation layer, AlGaN transition layers, an AlGaN buffer layer, a low temperature AlN insertion layer, an AlGaN main buffer layer, an AlGaN/GaN superlattice layer, an GaN channel layer, and an AlGaN barrier layer. Both sides of a top end of the HEMT device are a source electrode and a drain electrode respectively, and a middle of the top end is a gate electrode. A middle of the AlGaN barrier layer is etched through to form a recess, and a bottom of the recess is connected to the GaN channel layer. A passivation protective layer and a gate dielectric layer are deposited on the bottom of the recess, and the gate electrode is located above the dielectric layer.

Abstract: The invention discloses a durable super-hydrophobic fabric and a preparation method thereof. The preparation method comprises the following steps: soaking a fabric into a mixed solution of tetraethoxysilane and hydroxy-terminated polydimethylsiloxane; taking out the fabric and then placing it into a closed container filled with a hydrochloric acid solution and above the liquid level of the hydrochloric acid solution; reacting for 0.5-2 h under the temperature of 30-60 DEG C. to give the durable super-hydrophobic fabric. The fabric prepared according to the invention has a water drop surface static contact angle of more than 150° such that the water drop is easy to roll on the surface of the fabric, and has excellent chemical stability and mechanical durability. In addition, the preparation process is simple and pollution-free.

Abstract: A zero-valent iron pillared montmorillonite repair material relates to the field of environmental functional materials. A preparation method thereof is mainly to obtain the zero-valent iron pillared montmorillonite repair material by reducing hydroxyl-iron pillared montmorillonite at high temperature in a mixed atmosphere of hydrogen and nitrogen, and mainly includes: (1) preparation of Na-montmorillonite; (2) preparation of a polyhydroxy-iron pillared solution; (3) preparation of hydroxy-iron pillared montmorillonite; and (4) obtaining the zero-valent iron pillared montmorillonite repair material by means of high-temperature reduction-calcination in the mixed atmosphere of hydrogen and nitrogen. The zero-valent iron pillared montmorillonite repair material can be used for removing degradation-resistant organic pollutants, and degrading organics into small molecular organics by means of peroxymonosulfate (PMS).

Abstract: The present invention discloses a vertical structure nonpolar LED chip on a lithium gallate substrate and a preparation method therefor. According to the method, LED epitaxial wafers are grown on a lithium gallate substrate, wherein the LED epitaxial wafers comprise a GaN buffer layer grown on the lithium gallate substrate, a non-doped GaN layer on the GaN buffer layer, an n-type doped GaN thin film on the non-doped GaN layer, an InGaN/GaN quantum well on the n-type doped GaN thin film and a p-type doped GaN thin film on the InGaN/GaN quantum well. Then, electrode patterns are prepared on the surfaces of the LED epitaxial wafers by the steps of spin coating, photoetching, developing and cleaning, and an electrode metal is sequentially deposited on the upper surfaces of the epitaxial wafers. Then, the LED epitaxial wafers are transferred to a copper substrate.

Abstract: A treatment method for resource recycling of hexavalent chromium-containing residues is provided. This method comprises steps as follows: 1) adding water to the hexavalent chromium-containing residues and mixing uniformly; 2) adding mineralizers to a solution obtained in step 1) and stirring sufficiently to obtain a mixed liquid; and the mineralizers are sodium chlorate, sodium perchlorate and hydrochloric acid; 3) treating the mixed liquid by a hydrothermal method or direct heating; 4) after the heating treatment, naturally cooling a solid-liquid mixture to room temperature for holding; 5) separating solid residues and a chromium-containing supernatant, and washing filtered residues with water and then drying; and 6) recycling a chromium-containing solution for returning to a work section, or for a treatment of recycling chromium.

Abstract: The present invention belongs to the field of titanium alloy materials, and disclosed are a high-strength and low-modulus ?-type Si-containing titanium alloy, a preparation method therefor and the use thereof. The preparation method involves: preparing an alloy component with, in atomic percentage, 60-70% of Ti, 10-20% of Nb, 5-15% of Zr, 1-10% of Ta and 1-5% of Si and using sponge titanium, sponge zirconium, a tantalum-niobium intermediate alloy and silicon as raw materials, and then uniformly smelting the alloy component to obtain a solidified ingot; then, subjecting the resulting ingot to high temperature plastic deformation with a deformation temperature of 800-900° C.

Abstract: A method for manufacturing thin-specification high-Ti wear-resistant steel NM450 comprises the steps of preparing melted iron in a blast-furnace, preprocessing the melted iron, smelting the melted iron in a converter, refining the melted steel in a LF furnace, refining the melted steel in a RH furnace, conventional slab continuous casting, heating the slab in a heating furnace, dephosphorizing the slab by high-pressure water, heating the slab in a hot continuous rolling mill, performing ultra fast cooling, reeling, flattening, heating, quenching, tempering and finishing.

Abstract: The invention discloses a preparation method of a WC cemented carbide with adjustable alignment of plate-shape grains. According to the theoretical composition of the cemented carbide, the weighed W powder is composed of two raw W materials with significantly different particle sizes in a certain mass ratio. Also graphite powder and Co powder are weighed. W—C—Co powder is subjected to planetary ball milling with controlled process parameters; then, after plasma-assisted ball milling, W—C—Co composite powder composed of small-sized lamellar W sheets and large-sized lamellar W sheet is obtained; Finally dense cemented carbide containing plate-shape WC grains is obtained by press molding of the ball milled power and in-situ carbonization through sintering at a high temperature. The invention not only provides simple preparation process with low energy consumption, but also can regulate the degree of orientated alignment of the plate-shape WC in the sintered block.

Abstract: A novel sweat absorbing textile electrode comprises a textile electrode body and an electrical coupling member, the textile electrode body comprising a conductive foam and a conductive fabric wrapped around the conductive foam, the electrical coupling member being fixed on the conductive fabric; wherein a through hole is provided on the conductive fabric on the side in contact with the human skin. The textile electrode has a light weight, small size and soft texture. It fits on the skin, has good air permeability, and is capable to absorb sweat, which can prevent short circuit between electrodes caused by sweat and be used for collecting bioelectrical signal when sweat comes out from human body. It may also be applied in bioelectrical signal monitoring in high temperature, high humidity environment, and during daily exercise.

Abstract: The present invention provides a method for micro-grinding tip-accurately induced brittle fracture forming of a curved mirror surface. The method includes the steps of: grinding a surface of an optical glass material by means of a V-shaped tip of a diamond grinding wheel to form a V-shaped microgroove having a groove micro-tip; setting two supporting points with a distance of L therebetween on one side of the optical glass material where the microgroove is machined, providing a loading pressing head having a horizontal deviation distance of l between a loading point and the groove micro-tip on the other side of the optical glass material, and allowing the loading pressing head to perpendicularly apply a loading force F onto the optical glass material with a loading speed of ?, and forming a penetrated smooth curved mirror surface within 0.3 millisecond via the loading point of the loading force F and under induction of the groove micro-tip.

Abstract: A reinforced compound concrete beam-column joint containing demolished concrete lumps and a construction method are disclosed. The steel strip stirrups configured to constrain column longitudinal reinforcements of the reinforced compound concrete column containing demolished concrete lumps and the steel connection sheets with grooves are arranged in joint at positions of the upper and lower beam longitudinal reinforcements of the reinforced compound concrete beam containing demolished concrete lumps. The steel strip stirrups abut against the column longitudinal reinforcements. The steel connection sheets are welded to the steel strip stirrups. One end of the short steel bars with threads at one end is welded into the grooves of the steel connection sheets, and the other end is connected to the beam longitudinal reinforcement via a steel sleeve. The joint prevents the beam longitudinal reinforcements from passing through the joint and thus causing reinforcements congestion.

Abstract: The present invention provides a GaN-based microwave power device with a large gate width and manufacturing method thereof. The device includes an AlGaN/GaN heterojunction epitaxial layer, a first dielectric layer overlying the AlGaN/GaN heterojunction epitaxial layer, a strip-like source electrode, a drain electrode distributed in a shape of a fishbone, an annular gate electrode, a second dielectric layer separating upper and lower electrodes, and an interconnect metal electrode pad. The GaN-based microwave power device with the large gate width prepared according to the present invention, has a small phase shift of the signals, a small parasitic capacitance of the device, a high signal gain, high power added efficiency and a high output power. At the same time, the manufacturing process of the device is simple, the chip area is saved, and the device has a good repeatability.