45 results about "Fiber type" patented technology

Plied yarns and methods of constructing plied yarns from two different yarns, manufactured using different fibers wherein the plied yarns possess enhanced properties. The yarns developed and described herein are plied yarns, rather than, and in direct contrast to intimately blended yarns. Examples of the fibers and / or yarns utilized in forming the yarns of different fibers described herein, include but are not limited to 100% cotton, Modal, and Lyocell. The yarns described herein can be used for various end uses, including but not limited to formation of terry fabric for use in towels, robes, apparel, and the like.

This invention discloses an improved drafting device for a roving frame, comprising a frame, a fixed roller, a movable roller, an adjusting assembly, and a transmission assembly. The adjusting assembly forms a closed-loop system with a pressure sensor, a hydraulic cylinder, and a controller, employing a PID algorithm to achieve precise control of the pressure between the rollers. The transmission assembly utilizes a spiral bevel gear pair combined with a prism-perforated and progressive spring structure to ensure stable transmission during the lifting and lowering of the movable roller. The device also features adaptive PID parameter adjustment, automatically optimizing control parameters according to fiber type. Compared with traditional technologies, this invention offers higher pressure control accuracy, effectively improving production efficiency and intelligence, while reducing energy consumption and maintenance costs.

The optical fiber type light spot homogenizer comprises a machine frame, a laser source is arranged at one end of the machine frame, a multimode optical fiber corresponding to the laser source is arranged at the other end of the machine frame, the laser source emits a laser beam, the multimode optical fiber receives the laser beam, and the multimode optical fiber is connected with the machine frame. The multi-mode fiber laser is characterized in that the relative refractive index difference section of the inner side of the sunken inner cladding of the multi-mode fiber is in a two-stage step decreasing shape, and the center line of the laser beam and the center of the end face of the multi-mode fiber are aligned and offset in parallel by a section of radial offset. The device is small in size, low in cost, compact in structure, good in homogenization effect and stable in performance, and can be directly seamlessly integrated with an input laser source and an output optical fiber system. The optical fiber type light spot homogenizer assembly and the laser beam shaping system can achieve efficient light spot homogenization within the centimeter-level distance. The system can be applied to a vehicle-mounted laser radar, a vehicle-mounted head-up display, a multimode PON optical splitter, laser medical equipment or laser material processing equipment and the like.

This invention discloses a modified fiber-reinforced composite high-permeability concrete and its preparation method in the field of concrete technology. The concrete comprises the following components: silicate cement, fly ash, coarse aggregate, composite fiber, waterborne polyurethane emulsion, activated biochar, water-reducing agent, composite bacterial solution, photocatalyst, and water. By adding modified polypropylene fiber, modified carbon fiber, waterborne polyurethane emulsion, and activated biochar to the concrete raw materials, this invention enhances the mechanical properties of the concrete, improving its stability, compressive strength, and crack resistance. It also increases the void structure of the concrete, further improving its permeability. Simultaneously, the addition of microbial solution and photocatalyst enhances the self-healing and self-cleaning capabilities of the concrete.

The application provides a winding core spinning device based on a calculus principle and a method and application thereof. The device is provided with a negative pressure air suction port on a special-shaped plate, and a corresponding negative pressure airflow guide assembly is arranged above the negative pressure air suction port. Under the mutual cooperation of the diffusion flow guide hole and the negative pressure air suction mechanism, the spread fiber type short fibers with a certain width and uniformly distributed fiber height parallelism are obtained on the grid ring. Meanwhile, the short fiber sliver, core yarn and winding core yarn form a "y" shape structure in the winding core wrapping area. The core yarn self-rotation drives the short fiber sliver to be tightly wrapped and wound to the outer layer of the core yarn in the winding core wrapping area to form the winding core yarn. Then, the winding core yarn passes through the soft reinforcing winding core part, so that the wrapping layer is tightly attached to the yarn body under the action of temperature and pressure to form a good wrapping effect. The winding core yarn has a compact yarn body and a large core yarn proportion, solves the problems of small wrapping tightness, many wrapping exposed cores and low core yarn proportion of the core-spun yarn on the ring spinning machine, and greatly improves the yarn quality.

One or more aspects of the disclosure provides a nonwoven fabric comprising a single layer in which the single fabric layer comprises a plurality of different fibers in which each fiber type has desired functionality. In one aspect, a system for preparing a nonwoven fabric having a single fabric layer in which the single fabric layer comprises a plurality of different fiber types, is provided. The system includes a spin beam having a zoned distribution plate disposed upstream of a spinneret, the zoned distribution plate includes a plurality of distribution apertures arranged in zones, wherein each zone is configured and arranged to extrude a plurality of polymer streams that are of a different polymer type than polymer streams extruded by an adjacent zone to the spinneret to form a single layer having two or more types of fibers that are of a different type from each other.

The invention belongs to the technical field of organic solvent detection, and relates to a PTR-MS detection method for organic solvent residues in textiles, which adopts temperature programming dynamic thermal desorption combined with near infrared spectroscopy to synchronously characterize fiber types and moisture content, and regulates desorption parameters according to different matrix characteristics. Then, the thermal desorption gas is directly introduced into an ion mobility-proton transfer reaction mass spectrum combined system, by means of the multi-dimensional separation capacity of the collision cross section and the mass-to-charge ratio, a fragment mode is obtained through dynamic collision energy regulation and control, a multi-dimensional spectrogram library is constructed, rapid detection and accurate recognition of isomeride with similar structures and matrix interferents are effectively considered, and the detection accuracy is improved. According to the method, parameters obtained through the previous steps are integrated to form a six-dimensional data set, fiber-solvent interaction parameters and a graph neural network are combined to construct a matrix-dynamic coupling quantitative model, the influence of matrix adsorption / desorption balance and temperature on dynamics is fully considered, and the quantitative error caused by neglecting matrix-dynamic coupling in a traditional external standard / internal standard method is solved.

The utility model belongs to the field of textile machinery, disclose a kind of combined apron for apron type carding machine, it is made of metal apron strip (2) and elastic apron strip (1) compound, both are detachably mounted on same apron framework (3) by installation groove (8), can be realized individually replacement without interfering each other;Elastic apron strip (1) is close to fiber inlet, and metal apron strip (2) is set in the back side of elastic apron strip (1);Metal apron strip (2) is made of metal card clothing rack (4) and metal card clothing rack support (5);Elastic apron strip (1) is made of steel needle (7) implanted on base cloth (6) and base cloth (6).The utility model can be individually replaced metal apron strip, elastic apron strip without interfering each other when the change of fiber type or carding process, effectively open loose and separate impurities at apron inlet, maintain long-term stability of process gauge at the most tight place of outlet gauge, facilitate to obtain higher yield, carding quality.

The invention belongs to the technical field of hydrogen separation, and relates to a hollow fiber type electrically-driven proton exchange membrane hydrogen pump for hydrogen separation / compression, which is characterized in that the hollow fiber type electrically-driven proton exchange membrane hydrogen pump is formed by packaging one or more hollow fiber type proton exchange membrane electrodes, and hydrogen is separated / compressed from hydrogen-containing mixed gas at high purity under external voltage. Due to the hollow fiber type membrane electrode structure, the bundling packaging mode and the excellent pressure resistance, the specific surface area and the integration level of the proton exchange membrane hydrogen pump can be remarkably improved, and the application requirements of light-weight and large-scale hydrogen separation / compression are met.

The application discloses a kind of hybrid fiber reinforced geopolymer concrete dynamic growth factor prediction method and system, it is related to composite material technical field, including: based on the ratio of dynamic peak stress and quasi-static peak stress under given strain rate, obtain initial peak stress growth factor;Based on the ratio of dynamic elastic modulus and static elastic modulus, obtain the dynamic increase coefficient of concrete elastic modulus;In the case where static compression test piece size and dynamic compression test piece size are consistent, analyze the influence of fiber combination mode, fiber type and content and strain rate on the dynamic performance of test piece;Introduce the secondary fitting of fiber characteristic parameter to initial peak stress growth factor, obtain the modified peak stress growth factor;The dynamic increase coefficient of concrete elastic modulus is fitted by linear function, and the modified elastic modulus growth factor and critical strain rate are obtained.The application can accurately predict the dynamic growth factor of hybrid fiber reinforced geopolymer concrete, and then obtain the impact resistance of material.

The application discloses a fiber type horizontal angle indicating device based on a self-collimation principle and a method thereof, and relates to the technical field of horizontal angle indication.The device comprises a light source, a fiber weight module, a light intensity receiving module and a frame.The light source emits a space light which is coupled into the fiber weight module.The fiber weight module converts the direction of the incident light into a vertical downward direction and emits the light to a measured object.The measured object reversely couples the incident light into the fiber weight module.The fiber weight module emits the incident light to the light intensity receiving module.The light intensity receiving module converts the incident light into an electric signal.The frame is used for suspending the fiber weight module.The application is suitable for the installation and debugging process of high-end manufacturing equipment, measuring instruments and scientific test equipment, and provides high-sensitivity horizontal angle indication for the adjustment requirement of the spatial posture of a sensitive element and the high-precision level of the ground.

The invention discloses a resonance type multi-component fiber composite broadband wave-absorbing structure and a preparation method thereof, and belongs to the technical field of radar wave-absorbing material development. The wave-absorbing structure comprises a metal sheet and a wave-absorbing layer. The wave absorbing layer is of a multi-layer structure, and each wave absorbing layer is composed of a base material and a composite fiber absorbing layer on the surface of the base material. The composite fiber absorption layer has a periodic array structure; the periodic array structure comprises a plurality of absorption units, and each absorption unit is formed by connecting a fiber bundle A and a SiCf fiber bundle to form an H shape or a lamp-like shape; the shapes of the absorbing units in the composite fiber absorbing layers of any two adjacent wave absorbing layers are different; the fiber bundle A is selected from at least one of a SiCN fiber bundle and a SiBCN fiber bundle. According to the invention, specific fiber types with remarkable differential dielectric properties are selected to be combined and cooperated with the shape design among multiple layers, so that the wide effective absorption bandwidth and the strong wave-absorbing performance are realized under the condition of small thickness.

The invention provides a shaping control method and equipment under fiber structure characteristics, and relates to the technical field of textile shaping, and the method comprises the steps: obtaining the fiber type and fabric structure information of a pre-shaped textile, connecting a pressurization shaping machine, extracting operation parameters, simulating the deformation of fibers under different process conditions, and optimizing the process by taking the fiber structure stability as a target. And controlling the pressurizing setting machine according to the optimal parameter combination. The technical problems that the pressure parameter and the speed parameter of the pressurization setting machine are not matched with the fiber deformation characteristic, the fiber is easily stretched excessively or the structure is damaged, and the size stability of the set textile is poor are solved, and the effect that the size stability of the set textile is poor by associating the fiber structure characteristic with basic information and combining pressure parameter partitioning and speed parameter partitioning is achieved. The method has the technical effects that the deformation correction loss deviation of fibers under different process conditions is simulated, parameter differentiation is performed on a dry setting mode and a wet setting mode, optimization is performed by taking fiber structure stability maximization as a target, and the size stability of a set textile is improved.

The invention provides a conductive carbon additive as well as a preparation method and application thereof, and relates to the technical field of carbon materials. Specifically, an aqueous solution containing an organic carbon source and an organic nitrogen source is prepared, and a culture solution is obtained after high-temperature sterilization; adding fungus spores into the culture solution, and culturing to obtain hyphae; and sequentially carrying out liquid nitrogen treatment, vacuum freeze drying and high-temperature carbonization treatment on the cleaned mycelia to obtain the fiber type conductive carbon additive. The invention provides a novel fiber-type conductive carbon additive based on biomass derivation, which can effectively overcome the defects that sulfide electrolyte in an all-solid-state battery is easy to oxidize and decompose when being in contact with a traditional conductive carbon additive, the electrode structure stability is poor under the high-activity material content, and the energy density is limited.

The utility model discloses card clothing of a textile carding machine, which belongs to the technical field of textiles and comprises card clothing base cloth, and a steel needle body is arranged above the card clothing base cloth. The debugging assembly is arranged above the card clothing base cloth and can debug the height of the steel needle body according to different fiber processing requirements; through the arrangement of the debugging assembly, when textile processing encounters different fiber types or processing technologies, a worker can debug the angle of the steel needle body only by pulling the adjusting cloth, the higher steel needle is suitable for carding thicker fibers, scattering of fiber agglomeration and improvement of the uniformity of the fibers are facilitated, and for thinner fibers, the adjusting cloth can adjust the angle of the steel needle body only by pulling the adjusting cloth. The lower steel needle can reduce damage to fibers and avoid excessive stretching, and the adjustable angle of the steel needle body ranges from 60 degrees to 150 degrees, so that the textile processing quality can be effectively improved, and different production and processing requirements are met.

The application discloses a resonant multi-component fiber composite broadband wave-absorbing structure and a preparation method thereof, and belongs to the technical field of radar wave-absorbing material development. The wave-absorbing structure comprises a metal sheet and a wave-absorbing layer; the wave-absorbing layer is a multi-layer structure, each layer of the wave-absorbing layer is composed of a base material and a composite fiber absorbing layer on the surface of the base material; the composite fiber absorbing layer has a periodic array structure; the periodic array structure comprises a plurality of absorbing units, each absorbing unit is connected by a fiber bundle A and a SiCf fiber bundle to form an H-shaped or lamp-shaped shape; and the shape of the absorbing units in the composite fiber absorbing layers of any two adjacent layers of the wave-absorbing layer is different; the fiber bundle A is selected from at least one of a SiCN fiber bundle and a SiBCN fiber bundle. According to the application, specific fiber types with significant different dielectric properties are combined and the shape design among the multi-layers is cooperated, so that a relatively wide effective absorbing bandwidth and relatively strong wave-absorbing performance can be realized under a relatively thin thickness.

The present application relates to a kind of silicon carbide fiber composite material rotary body member and its winding forming method, belong to silicon carbide fiber reinforced composite material technical field, to solve the low precision of pre-preg paving technology in prior art, low production efficiency, process difficulty and low product quality, the winding of silicon carbide fiber is difficult to accurately control each parameter, leading to the quality of the rotary body member prepared is poor etc. One of the problems.The method of the present application can design process parameters and fiber path based on CADWIND software according to different component structure parameters, realize the flexibility and adaptability of process. Fiber type, fiber length, fiber quantity and resin parameters can be adjusted according to specific requirements to meet different application scenarios.

This invention belongs to the field of animal fiber processing and testing technology, and relates to a method for controlling the color stripping process and identifying the fiber type of special animal fibers. The method first obtains the initial color parameters, average fineness parameters, and scale contrast parameters of the fiber to be treated, and selects the corresponding process window from a preset color stripping parameter matrix accordingly. Then, it sequentially performs a first-stage reduction release bath pre-stripping, an intermediate water wash, and a second-stage acidic oxidation bath main stripping. During the main stripping process, dual endpoint control is performed using oxidation-reduction potential and online color difference change rate. After stripping, a termination reduction wash is performed, and the stripping response characteristics are output. These response characteristics are then fused with morphological and / or spectral characteristics to achieve the identification of the type of special animal fiber. This invention has the advantages of stable stripping effect, minimal fiber damage, strong process adaptability, and high identification accuracy.

The invention discloses a method for predicting the multilayer stacking height of 3D printing fiber concrete, and the method comprises the following steps: 1, collecting fiber parameters, including a volume fraction, a length-diameter ratio and an orientation factor; step 2, printing a single-layer strip and measuring the height of the actually measured single layer; thirdly, multiple layers are printed at a long interlayer interval, and interlayer bonding loss is obtained through linear fitting of total height-layer number; 4, under the target interlayer interval, measuring a scatter diagram of the first-layer settlement amount changing along with the layer number, and performing linear fitting to obtain a first-layer settlement amount model; 5, establishing a total compression settlement model and a bonding loss model; and step 6, obtaining a stacking height analytic expression of any layer number. According to the 3D printing fiber concrete multi-layer stacking height prediction method, parameters needed by the model are few and can be explained, on-site rapid adaptation is facilitated, and accurate prediction and online correction under different fiber types / mixing amounts and printing time intervals are achieved; the calibration process is short, and the recalculation operability is high.

The application discloses a kind of directional reinforced puncture fabric and its forming method, comprising: step 1: according to the design of fabric directional reinforcement requirement, unit layer includes at least one fiber layer, and the unit layer formed by at least one fiber layer is distributed with fiber in multiple directions, and the volume content ratio of fiber distributed in multiple directions is not all same;Step 2: the fiber layer in the first layer unit layer is sequentially laid in the puncture device and puncture pressurization setting is carried out;Step 3: the fiber layer of remaining unit layer is sequentially carried out puncture pressurization setting according to step 2 until reaching predetermined height;Step 4: the position of puncture needle is replaced by Z direction fiber bundle one by one, and finally three-dimensional fabric is formed.The application utilizes the fiber type, fiber structure, organization structure and fiber layer combination design of fiber layer, realizes the limit promotion of fabric specified single or multiple direction fiber volume content or performance, forms directional reinforced puncture fabric to meet the requirement of material directional high performance.

The utility model relates to a kind of wiping fiber type wire stripping pliers, including wire stripping pliers, the sleeve joint handle sleeve on the handle of wire stripping pliers, at least one handle is connected cleaning assembly, cleaning assembly uses first clean fiber device or second clean fiber device, they all include fixed plate, fixed plate is equipped with the plugboard of plug-in in handle sleeve, cover plate is connected on fixed plate by hinging axle, torsional spring is connected on hinging axle, torsional spring and fixed plate and cover plate correspond with each other, lower cleaning cotton and upper cleaning cotton of corresponding cooperation are connected on fixed plate and cover plate.The utility model has the advantages that: the cleaning assembly used is installed flexibly, can be used by operators with different operation habits, when cleaning fiber, since the area of cleaning cotton is larger, optical fiber is easy to place, then two cleaning cottons are used to extrude optical fiber, optical fiber is wiped, it is convenient to operate, and there is no phenomenon of broken fiber.Owing to the fact that the hand of operator does not directly contact with alcohol, alcohol does not hurt hand, and fiber is cleaned.

The utility model relates to the technical field of wiredrawing equipment, and discloses concrete anti-cracking fiber wiredrawing equipment which comprises a bottom plate, a fiber wiredrawing machine, a cooling structure and a winding structure are respectively mounted on the bottom plate, an adjusting structure is mounted in the cooling structure, the fiber wiredrawing machine is fixedly mounted on one side of the top end of the bottom plate, and the fiber wiredrawing machine is fixedly mounted on the other side of the top end of the bottom plate. According to the adjusting structure, the screw rotates to control the roller to move in the water tank, cellosilk discharged from the fiber drawing machine penetrates through the bottom of the roller through the first guide roller and then is connected to the winding drum through the second guide roller, the cellosilk is cooled by water in the water tank, the temperature of the cellosilk is effectively reduced through water cooling, and the service life of the cellosilk is prolonged. The negative influence of the temperature on the fiber performance is reduced, the mechanical performance and toughness of the fibers are guaranteed, the tension of the fibers can be adjusted by adjusting the position of the roller in the water tank according to different fiber types, different production requirements can be met, the tension and cooling process can be coordinated, and the cooling effect is more uniform.

This invention discloses a dual-modal air-jet control method for foreign fibers in seed cotton, relating to the field of intelligent control technology. The method includes: acquiring target seed cotton and generating a list of foreign fiber types and a list of foreign fiber size distribution characteristics; identifying foreign fiber weight characteristics and generating a list of unit foreign fiber weight information; sampling and analyzing the target seed cotton to generate unit seed cotton weight information; performing air-jet control analysis under dual-air-jet separation modes to generate a first air-jet control model corresponding to the first separation mode and a second air-jet control model corresponding to the second separation mode; locating the first-mode separated foreign fiber weight list and the second-mode separated foreign fiber weight list; generating first-mode air-jet control parameters and second-mode air-jet control parameters; and controlling a seed cotton foreign fiber cleaning machine to sequentially perform air-jet control on the target seed cotton. This invention solves the technical problems of low efficiency and low accuracy in seed cotton foreign fiber cleaning in existing technologies, achieving the technical effect of improving the efficiency and accuracy of seed cotton foreign fiber cleaning.

The application provides a spiral tensile fiber concrete preparation method with high anti-explosion performance, belongs to the field of fiber reinforced concrete, and comprises the following steps: according to the fiber type and mechanical performance parameters, the diameter ratio and wrapping angle of the spiral tensile fiber are predicted based on deep learning, and the spiral tensile fiber is prepared; the spiral tensile fiber is embedded into concrete with different matrix strengths, the negative Poisson's ratio of the spiral tensile fiber is determined after curing, and the concrete matrix strength grade corresponding to the maximum negative Poisson's ratio is recorded; under the concrete matrix strength grade corresponding to the maximum negative Poisson's ratio, a plurality of groups of mixing ratios are generated, the mechanical performance prediction value is obtained based on deep learning according to the spiral tensile fiber characteristic parameters and the mixing ratios, the fitness of the mechanical performance prediction value and the target value is calculated, the matrix mixing ratio is searched based on a genetic algorithm, and the matrix mixing ratio is verified; and the concrete is prepared according to the matrix mixing ratio and the spiral tensile fiber; the preparation system is also provided; and the anti-explosion performance of the concrete is improved.

The application discloses a kind of fiber reinforced geopolymer composite material and its preparation method and application, belong to geopolymer material technical field.The application takes red mud and blast furnace slag as main cementing material, combines bamboo fiber and sisal fiber, constructs plant fiber reinforced geopolymer mortar green composite system, and the influence law of alkali equivalent, fiber type and fiber content on the statics performance of material is systematically analyzed.The difference of the reinforcing effect of bamboo fiber and sisal fiber is compared and studied, and it is found that sisal fiber has more advantages in crack inhibition, energy dissipation toughening and impact resistance performance improvement, which provides a basis for fiber selection of plant fiber reinforced geopolymer material.Combining with SHPB test, drop hammer impact test, the impact resistance performance of plant fiber geopolymer material is systematically evaluated from material, specimen to component level, and the sisal fiber geopolymer material provided by the application has potential application value in impact resistance engineering components.

The invention discloses a carbon fiber modified polyketone composite material and a preparation method thereof, and the preparation method comprises the following steps: mixing polyketone, a compatilizer and an auxiliary agent to obtain a premix; adding the premix into a main feeding hopper of a double-screw extruder, adding the modified short carbon fibers into a hopper of a forced side feeding machine, and carrying out melt extrusion to obtain a carbon fiber modified polyketone composite material; the processing temperature of melt extrusion is as follows: a conveying section is 140-160 DEG C, a melt plasticizing section is 220-235 DEG C, a side material section is 220-230 DEG C, a mixing dispersion section is 220-230 DEG C, an exhaust section is 220-230 DEG C, a metering homogenization section is 220-235 DEG C, and the temperature of a machine head is 180-200 DEG C. According to the application, through a synergistic enhancement strategy of interface bridging and construction of a nanometer material-carbon fiber-POK resin three-dimensional mechanical interlocking network, and through optimization of POK resin type selection, carbon fiber type selection, a carbon fiber coating, a carbon fiber length-diameter ratio and the like, a processing window of polyketone is widened, and the heat resistance of the polyketone is improved.

The utility model belongs to the technical field of acoustic effect adjustment, and particularly relates to an acoustic effect adjusting module which comprises a mounting base. A mounting groove is formed in the mounting base; a plurality of groups of screw holes are formed in the outer side of the mounting base; counter bores are formed in the outer sides of the screw holes; most of the acoustic modules are filled with some fiber materials, after long-term use, fibers are broken, dust escapes into the air, corona is generated, and potential safety hazards are formed, the sound insulation assembly is placed in the mounting groove, and the top of the sound insulation assembly and the mounting base are kept flat, so that the sound insulation effect is improved. And the fiber type material filled in the sound insulation assembly is sealed in the mounting groove, so that the situation of fiber dissipation of the fiber sound absorption material after long-term use is reduced, and the possibility of potential safety hazards is reduced.

The invention discloses a preparation method of an environment-friendly blanket, and relates to the technical field of blanket preparation. Fiber blending; performing ultrasonic-assisted weaving; and performing vacuum freeze drying. According to the invention, a polycaprolactam material and a polyester PET material in the marine waste fishing net are respectively subjected to differential depolymerization by adopting a glycolic acid-citric acid composite system and an ethylene glycol-zinc acetate catalytic system; cotton pulp cellulose is activated by an alkali-urea composite system and then is subjected to graft copolymerization with pretreated soybean protein isolate to prepare plant protein-cellulose composite fibers, and an interweaving weaving process and a vacuum freeze drying process are matched, so that resource utilization of the marine waste fishing net and collaborative optimization of the performance of the fibers for the environment-friendly blanket are realized. The problems of low depolymerization rate, single regenerated fiber type and insufficient functionality of fishing nets made of specific materials due to the fact that a single depolymerization system is mostly adopted for treating marine waste fishing nets in the prior art can be solved.

The invention discloses a hybrid mode-locked fiber laser based on SESAM and NALM mechanisms. The disclosed laser comprises a pump laser, a wavelength division multiplexer, a fiber beam splitter, a nonreciprocal phase shifter, a gain fiber and a fiber type SESAM. The reflective fiber SESAM is inserted into the NALM mode-locked fiber laser, the mode-locked fiber laser with the combined action of two mode-locked mechanisms is achieved, compared with a common mode-locked fiber laser, the mode-locked fiber laser has the advantages of being low in starting threshold value, wide in mode-locked range and low in output noise, and the device is simple in structure, has feasibility of productization and high integration and is suitable for large-scale popularization and application. And meanwhile, the method has universality and can be widely applied to different types of industrial lasers, optical frequency combs and the like.

A method of dissolving an aramid material comprising: arranging aramid material in a solvent, and allowing the aramid to dissolve to produce a aramid solution. Also disclosed is use of a solvent for dissolution of aramid, and an aramid solution comprising para-aramid dissolved in a solvent. Also disclosed a method of producing an aramid solution from a mixed fibre composite material, the method comprising: providing a material comprising fibres of a first fibre type and fibres of a second fibre type, the fibres of the first fibre type comprising aramid, and the fibres of the second fibre type comprising non-aramid; arranging the material in a solvent; and allowing the aramid fibres to dissolve to produce an aramid solution. Further disclosed is a method of making aramid fibres from such solutions. The solvent comprises DMSO, 1.5 wt / wt% to 10 wt / wt% KOH and 1.5 to 10 wt / wt% water.