30results about How to "Reduce tensile strain" patented technology

A stent (30) formed from cannula and having flexible segments (31) and high hoop strength segments (32) alternating therealong. Longitudinal struts or tie bars (41) interconnect the segments. Minimal length reduction of the strut occurs upon expansion. In the high hoop strength segment (32), struts (37) in a zig-zag configuration (Gianturco Z-stent) are initially parallel in the unexpanded strut condition. In the flexible segment (31), struts (58) extend from a respective C-shaped bend (59) to converge at the opposite ends thereof when unexpanded. In one embodiment, certain adjacent struts (39–41) of the hoop segment are spaced apart by elongated openings or gaps (46, 48) interposed therebetween and interconnected at their respective ends (42, 44) to form a T-shaped strut interconnection (45). The selected width (50, 51) of the first and third struts (54, 57) increases toward the ends (47, 48) of the elongated openings (46, 48) adjacent the strut interconnection (45). This strut width increase about one end of the strut significantly reduces the tensile strain exhibited about the opening end when the stent is radially expanded during manufacture. The tip length (52, 55) of the struts about the interconnection (45) is also adjusted (increased) along with the other C-shaped strut interconnections (59, 71) to further distribute the tensile strain developed during radial expansion.

The invention provides a polypropylene composition and a polypropylene material as well as an application thereof. The polypropylene composition comprises polypropylene, a nucleating agent and an antioxidant, wherein the nucleating agent comprises a crystal form alpha nucleating agent and a crystal form beta nucleating agent, the crystal form alpha nucleating agent is selected from one or more of an inorganic crystal form alpha nucleating agent, a sorbitol nucleating agent and an organic phosphate nucleating agent, and the crystal form beta nucleating agent is selected from one or more of a mixture of binary acid and an II Ath group of metal salts, a rare earth crystal form beta nucleating agent and an amide nucleating agent. The polypropylene material prepared from the polypropylene composition provided by the invention can be used for well integrating effects of relatively low tensile strain, relatively high tensile strength and relatively good heat resistance and long-term creeping strength, and has great industrial application prospects.

A layer structure for a normally-off transistor has an electron-supply layer made of a group-III-nitride material, a back-barrier layer made of a group-III-nitride material, a channel layer between the electron-supply layer and the back-barrier layer, made of a group-III-nitride material having a band-gap energy that is lower than the band-gap energies of the other layer mentioned. The material of the back-barrier layer is of p-type conductivity, while the material of the electron-supply layer and the material of the channel layer are not of p-type conductivity, the band-gap energy of the electron-supply layer is smaller than the band-gap energy of the back-barrier layer. In absence of an external voltage a lower conduction-band-edge of the third group-III-nitride material in the channel layer is higher in energy than a Fermi level of the material in the channel layer.

The invention provides a geotechnical grille for reinforcing highway subgrade, as well as an application method thereof. A grille net is formed by vertically and horizontally weaving high-strength and high-modulus polyvinyl chloride polymers, so as to increase the tensile strength of reinforced belts; an outer layer of the grille is coated with a modified rubber coating; rubber is mixed with anti-aging agent, antioxidant, light screener and other master batches, so as to increase the creep resistance and corrosion resistance of the reinforced belts; surface layers of the longitudinal and transverse reinforced belts of the grille are provided with coil-shaped embossed threads so as to increase friction force with soil; meshes of the grille are round so as to reduce stress concentration and increase the extensibility of the reinforced belts; and nodes of the reinforced belts of the grille are provided with bilateral strengthening columns, so as to stop the slippage between soil body and the grille, increase the shearing resistance of the subgrade, balance settlement and prevent the grille from being pulled out of the subgrade. The geotechnical grille has the advantages that the grille is high in the strength of polymer materials, little in creep because of the modified rubber smeared outside, high in tensile strength and low in tensile strain, and the round meshes, the threads of the reinforced belts and the strengthening columns fully occlude the soil body so as to form a space compound strengthening structure, thereby improving the entire shearing strength and settlement balancing performance of the subgrade.

It relates to a extension workmanship supplementary method, stretching plate material into low end and high end materials with at least one rib being extended on the circumference of the low end material. It also provides a extension mold, with convex and concave mold are of the same shape with high end and low end and at least one boss at the surrounding area of the low end. In this way, it can supplement extension for low end material, strengthening deformation rigidity of it, eliminating partial wrinkling of the parts, reducing flowing resistance, increasing material's flow into high end material of the supplement piece to reduce the stress deformation of the material to eliminate breach.

The invention relates to the technical field of highway roadbed construction, in particular to a construction method based on geonet reinforced roadbed, the geogrid network is made of high-strength and high-modulus polyvinyl chloride polymer vertically and horizontally, and the outer layer of the grid is covered with modified Rubber coating, the rubber is mixed with anti-aging agent, antioxidant and light shielding agent and other masterbatches, the mesh of the geogrid is circular, and there are double-sided reinforcement columns at the joints of the geogrid ribs, and the length of one side is about 3.5cm , There are ring-shaped embossed threads on the surface of the longitudinal and transverse ribs of the grille. In the present invention, the high-strength and high-modulus polyvinyl chloride polymer material has high strength, the outer layer is coated with modified rubber, the creep is small, and it has the properties of high tensile strength and low tensile strain.

The present invention relates to an optical fiber grating-based surrounding rock internal strain monitoring method. According to the method, a bare optical fiber grating sensor, an U-type stainless steel test piece, a metal gasket and an encapsulation steel pipe are adopted to form an optical fiber grating pre-tensioning device; compression strain in surrounding rock measured by the optical fiber grating pre-tensioning device is the decreased tension strain of the optical fiber grating sensor; and the optical fiber grating sensor is always in a tensioned state in a whole monitoring process, and therefore, the accuracy of a measurement result can be ensured, and the survival rate of the fiber grating sensor can be improved.

A buried semiconductor laser exhibiting a reduced dislocation of a contact layer is achieved. A buried semiconductor laser, comprising: an n-type indium phosphide (InP) substrate; an active layer disposed on the n-type InP substrate; block layers provided so as to bilaterally disposed on both sides of the active layer; a clad layer provided so as to cover the active layer and the block layers; and a p-type gallium indium arsenide (InGaAs) contact layer provided on the clad layer, wherein the p-type InGaAs contact layer has a compressive strain.

The invention discloses a red light semiconductor laser based on a GexSi<1-x> variable lattice constant matrix. The laser structurally comprises an N-surface electrode, a germanium substrate, a strainbuffer layer, a germanium-silicon matrix layer, a buffer layer, a lower limiting layer, a lower waveguide layer, a quantum well, a quantum barrier, an upper waveguide layer, an upper limiting layer,a barrier layer, a dielectric film, an ohmic contact layer and a P-surface electrode in sequence from bottom to top. According to the red-light semiconductor laser, the tension strain of the quantum well is reduced while the active region lasing wavelength is shortened, the problem that the active region with large tension strain has many defects in an ultra-short wavelength red-light laser can besolved, and meanwhile, the output power and the photoelectric conversion efficiency of a band laser are also improved.

The invention discloses a stretchable layered thermal camouflage material and a preparation method thereof.The layered thermal camouflage material comprises a carbon material electrode layer, an ionic conductive gel layer and an electrochromic functional layer which are sequentially arranged from bottom to top, and the preparation method comprises the steps that a porous thermoplastic polyurethane fiber membrane is prepared through electrostatic spinning; soaking in an aqueous dispersion of carbon black particles and carboxylated carbon nanotubes, drying to obtain a carbon material electrode layer, adding a waterborne polyurethane aqueous solution and an ionic liquid into water, mixing, coating the surface of the electrode layer with the mixture, and drying to obtain an ionic conductive gel layer; and soaking the porous thermoplastic polyurethane fiber membrane in a mixed solution containing conductive macromolecules, drying, attaching to the gel layer, and packaging to obtain the product. The stretchable layered thermal camouflage material is excellent in tensile property, the tensile strain can reach 460%, the thermal camouflage property of the stretchable layered thermal camouflage material still keeps stable after 5000 times of cyclic stretching recovery under the tensile strain of 60%, and the preparation method is low in cost and high in practicability.

A method and structure are provided for implementing manufacture of a printed circuit board (PCB) with one of an infrared (IR) reflective mask or a novel solder mask to minimize coefficient of thermal expansion (CTE) mismatch between PCB laminate and plated through hole (PTH) copper. At least one of an IR-reflective mask and a solder mask composition for use in IR reflow processes is created such that radiant heat is reflected away from the major portion of the PCB yet permitted to impinge upon the PTHs. The copper within the PTH expands due to radiant heating while the bulk laminate expansion is significantly reduced due to the reflected IR radiation. Consequently, the CTE mismatch is minimized and tensile strain of the copper in the PTH is reduced, providing enhanced reliability.

The invention discloses sulfur-containing furandicarboxylic acid polyester, and relates to the field of biomass-based high polymer materials, and the structural formula of the sulfur-containing furandicarboxylic acid polyester is shown in the specification, n is more than or equal to 5 and less than or equal to 3000, R on the main chain is a disulfide bond, and R is any one of structures shown in the specification. The invention also provides a preparation method of the polyester. The invention has the beneficial effects that the polyester has a unique chemical structure and excellent mechanical properties, and the mechanical property parameters after tabletting and film making are as follows: the breaking strength is 14.7 Mpa, and the elongation at break is 420%.

The invention relates to a novel road base structure, which comprises an upper base layer (3) and a lower base layer (4) and is characterized in that the strength of the base layers is 6.0 to 9.0 MPa;the upper base layer (3) is waste rubber modified cement stabilized macadam; the lower base layer (4) is cement stabilized macadam; the upper base layer (3) is prepared from the following mineral aggregate (by weight): 15%-25% of 10-30 mm macadam, 20%-27% of 10-20 mm macadam, 15%-25% of 5-10 mm macadam, 17%-21% of stone nitrate and 2%-12% of waste rubber powder, wherein cement is added in an amount which is 5-10 percent of the total weight of the mineral aggregate, and the thickness of the upper base layer (3) is 15-25cm; and the lower base layer (4) is prepared from the following mineral aggregate (by weight): 15%-25% of 10-30 mm broken stone, 20%-27% of 10-20 mm broken stone, 15%-25% of 5-10 mm broken stone and 23%-33% of mirabilite, wherein cement is added according to the dosage of 5-7% of the total weight of the mineral aggregate, and the thickness of the lower base layer (4) is 15-25 cm. The structure can reduce the tensile stress and tensile strain of the bottom of the asphaltsurface layer, reduce the sensitivity to wheels, reduce reflection cracks caused by cracking of the lower base layer and reduce cracks of the asphalt surface layer.

A conveyor system for transporting goods has an endless conveyor belt and two support tracks, disposed one above the other, for supporting the conveyor belt. The conveyor belt is formed with a plurality of transverse beams which are spaced apart from one another in a conveying direction of the conveyor belt. Carrying rollers are supported on the transverse beams. The support are formed with carrying cables on which the rollers are supported. The weight of the conveyor belt is transmitted onto the carrying cables.

The invention relates to a full-thickness asphalt pavement structure taking steel wire mesh reinforced asphalt concrete as a base layer, and the pavement structure sequentially comprises a high-rut-resistance asphalt concrete surface layer, a high-rut-resistance asphalt concrete surface layer and a high-rut-resistance asphalt concrete surface layer from top to bottom, the thickness of the high-modulus asphalt concrete bonding layer is 6-15 cm; the thickness of the high-modulus asphalt concrete base layer is 13-22 cm; in the steel wire mesh layer, the diameter of steel wires of a steel wire mesh is 0.8-2.0 mm, and the hole size of the steel wire mesh is between 20 mm * 20 mm and 80 mm * 80 mm; the thickness of the slurry seal layer is 6-10 mm; and the steel wire mesh needs to be subjected to tackifying and roughness increasing treatment. The steel wire mesh is arranged on the slurry seal and located on the lower portion of the pavement structure, the direction of steel wires is consistent with the stress direction of the overlay, the advantage of high tensile strength of steel wire materials can be fully played, fine steel wires are selected, good bond stress can be formed between the asphalt mixture and the steel wires, interlayer defect gaps are reduced, and the strength of the pavement structure is improved.