Yanshan University

A ceramic tool material, in particular with piezoelectric effect and a preparation method thereof, and a cutting tool. The ceramic tool material includes the following raw materials by weight: 30-70 parts of matrix material, 30-70 parts of piezoelectric material, 5-10 parts of binder, and 10-20 parts of reinforcing phase and can be made into cutting tools. The cutting tool has a piezoelectric effect and excellent mechanical properties and can convert the cutting force signal into the charge signal during machining. By collecting charge signals, a cutting force can be measured and ceramic cutting tool condition can be monitored. Cutting force measurement function and high mechanical properties are integrated. A ceramic tool material with piezoelectric effect can measure the cutting force on the premise by meeting the cutting performance requirements.

A dispersion-compensation microstructure fiber uses pure silica glass as the background material. It includes the core, the first-type defects, the second-type defects and the cladding. The air holes in the fiber cross section are arranged in the equilateral triangle lattice with the same adjacent air-hole to air-hole spacing. The core is formed by omitting 1 air hole. The first-type defects are formed by the 6 air holes locating at the vertices of hexagonal third-layer porous structure surrounding the core and their surrounding background material. The second-type defects are formed by the air holes in the first air-hole layer surrounding each first-type defect and their surrounding background material. The second-type defects act as the porous structure to surround the first-type defects and the fundamental defect modes, and can also combine with the first-type defects to act as the core of the second-order defect modes.

A photocurable composite hydrogel matrix precursor, a preparation method thereof and a scaffold with same. The photocurable composite hydrogel matrix precursor includes gelatin methacrylate, sodium alginate, sodium carboxymethyl cellulose and chondroitin sulfate, where the mass ratio of a photoinitiator to the gelatin methacrylate to the sodium alginate to the sodium carboxymethyl cellulose to the chondroitin sulfate is (0.2-0.3):(8-10):(1-3):(0.6-0.8):(0.05-0.07). By adoption of the precursor, a cell-loaded printing hydrogel scaffold can be obtained through an extrusion-based 3D bio-printing technology, and the scaffold is controllable in form, good in moldability, high in precision, and has good stability; the biocompatibility and bioactivity are high, so that a good growing environment can be provided for fibroblasts; and the preparation process is simple and can be completed within a short time, moreover, the porosity and mechanical performance of the 3D printing hydrogel scaffold can be adjusted by adjusting the raw material ratio.

The present application discloses a conductive high-strength diamond/amorphous carbon composite material and a preparation process thereof. The diamond/amorphous carbon composite material is composed of an amorphous carbon continuous phase and multiple separate diamond phases embedded in the amorphous carbon continuous phase, wherein the diamond phases exhibit an ordered sp3 hybrid state, and the amorphous carbon continuous phase exhibits a disordered sp2 hybrid state. The present application further discloses a process for preparing the above diamond/amorphous carbon composite material. The process comprises using sp3 carbon powder or glassy carbon as a raw material to obtain the above-mentioned material by sintering. The diamond/amorphous carbon composite material shows good electrical conductivity, good electrical discharge machining ability, good chemical stability and light weight, and has broad application prospects in aerospace, automobile industry and biomedical equipment.

A copper oxide with a hollow porous structure, a preparation method therefor, and a use thereof are provided. The copper oxide with a hollow porous structure is of a hollow octahedral structure, and has a size of 200-400 nm and a specific surface area of 23.5-79.6 m 2 /g, where the surface of the octahedron is composed of copper oxide nanoparticles having a size of 14-33 nm, and pore structures are formed among the copper oxide nanoparticles. The copper oxide with the hollow porous structure has good conductivity, high hydrophilicity and good catalytic performance, can substantially reduce the detection potential and greatly improve the detection sensitivity and the anti-interference performance when used for the electrochemical detection of pesticides.

A rail welding transition material resistant to stress corrosion damage and preparation method thereof, belonging to the technical field of welding transition materials. The rail welding transition material resistant to stress corrosion damage includes the following components in mass percentage: 0.02-0.04 percent (%) of Carbon (C), Silicon (Si)≤0.20%, 6.5-7.0% of Manganese (Mn), 11.0-11.5% of Nickel (Ni), 17.6-18.0% of Chromium (Cr), 2.1-2.4% of Molybdenum (Mo), 0.02-0.04% of Nitrogen (N), 0.05-0.15% of Niobium (Nb), 0.05-0.15% of Vanadium (V), Phosphorus (P)≤0.015%, Sulfur(S)≤0.010%; with the balance being Ferrum (Fe).

The present disclosure relates to metal material casting-rolling forming technology, and specifically to a casting-rolling method and apparatus based on a multi-layer heterogeneous composite roll sleeve. By alternately arranging a plurality of metal components on the composite roll sleeve and adjusting distribution of the metal components in the composite roll sleeve according to structural parameters and process parameters of the monometallic metals and layered metal composite materials, a layer thickness of the metal components at different radial positions of the composite roll sleeve is determined based on the solidification range of monometallic metals and the offset of the solidification point position in the heat transfer process of layered metal composite materials. This can significantly improve forming quality of strips.

The present invention relates to the field of robotic arm teleoperation technology, and specifically to a construction method and system for real-time teleoperation of a dual arm and hand robot based on vision guidance, which includes setting up a first experimental platform, acquiring pose information of the dual arm and hand robot and a homogeneous transformation matrix of an end joint and transforming a first coordinate system; setting up a second experimental platform; performing calibration by a plurality of cameras and transforming a second coordinate system; obtaining spatial transformation pose information of the end joint of the robotic arm under a tracking state, reading finger pose data, and performing real-time following. The real-time teleoperation system of the present disclosure includes a control system host, an operation glove, an optical locator, a positioning coordinate plate, a marker ball tool, and a dual arm and hand robot. The present disclosure introduces a method of identifying the marker ball tool by the optical locator into the teleoperation control of the dual arm and hand robot, which is more accurate and faster. Meanwhile, the method of remotely controlling the robotic arm by an operator wearing the operation gloves can provide better human-machine interaction function.

Disclosed in the present invention is a preparation method for an anisotropic Nd 2 Fe 14 B/α-Fe bulk nanocrystalline composite permanent magnet material. The preparation method comprises the following steps: preparing a master alloy; crushing the master alloy into bulks, and, by means of a melt rapid quenching method, preparing amorphous ribbons; grinding the amorphous ribbons to obtain amorphous powder; cold-pressing the powder into bulks; and placing the bulks into a stainless steel mold, and heating and then rolling same, the stainless steel mold being of a plate-shaped structure, and a chamber for accommodating the bulks being formed in the stainless steel mold along the thickness direction thereof. The present invention presses the NdFeB amorphous powder into bulks, embeds same in the stainless steel mold, and performs rolling at a temperature below a crystallization temperature, so as to achieve high-temperature amorphous material crystallization.

A ceramic tool with integrated temperature sensing and cutting functions and preparation method and application thereof. The ceramic tool comprises a ceramic matrix, a positive thermoelectric layer and a negative thermoelectric layer being provided on two surfaces of the ceramic matrix; the ceramic matrix being formed by sintering a first matrix material, a first binding agent and a first reinforcing phase, and the thermoelectric layer being formed by sintering of a thermoelectric material; the first matrix material comprises one or more of Al 2 O 3 , Si 3 N 4 and CBN; the first binding agent comprises one or more of Mo, Ni, Co, W and Cr; the first reinforcing phase comprises one or more of TiC, WC, SiC, MgO, Cr 2 O 3 , TiO 2 and ZrO 2 ; the thermoelectric material for the positive thermoelectric layer comprises ZrB 2 and SiC; the thermoelectric material for the negative thermoelectric layer comprises ZrB 2 , SiC, and graphite.