A foldable, frameless emergency shelter is constructed from a radial array of bendable yet rigid panels such as of a foamed plastic. Panels have adjoining edges with matching convexly curved profiles. The edges are always held to each other with a flexible fastener such as an adhesive tape. During erection, a flat panel inherently deforms into a curved cylindrical tapered shape enclosing a space. A door and an optional floor are provided. The shelter has a rigid conical cap including holes for guy ropes, a door and an optional window.

Disclosed is a method for urea finishing. A urea solution is subjected to crystallization and, other than in conventional processes, the urea crystals are shaped by exerting mechanical force onto them. Thus, the conventional prilling or granulation finishing steps can be avoided, and so are the corresponding emissions of ammonia and/or dust. The crystallization comprises a flash crystallization. The invention also pertains to the urea particles obtainable by the process, to a urea plant, and to a method of modifying an existing urea plant.

A dosage device for extruding a monocomponent or a bicomponent polymeric product, particularly for an automatic machine for forming a spacer frame, includes a first dosage assembly and a separate second dosage assembly for the dosage and feeding of the product, which can be activated, in a first feeding step and in a third feeding step, alternately so that one of them provides continuity of flow to an extrusion nozzle while the other one is in the reloading step. The first and second dosage assemblies are activated, in a second swapping step that is intermediate with respect to the first and third feeding steps, simultaneously and jointly, one of them having a flow-rate ramp that passes from the steady-state value to zero and the other one complementarily having a flow-rate ramp that passes from zero to the steady-state value.

A method of forming the body portion of a three-dimensional object from a polymerizable liquid by the process of continuous liquid interface printing is described. The body portion has a plurality of contiguous segments, and the process includes advancing a carrier for the object away from a build surface while irradiating a build region between the carrier and build surface in a pattern of advancing and irradiating defined by an operating mode. In the present invention, the operating mode is changed at least once during the formation of the body portion for different contiguous segments of the body portion.

A method of forming a three-dimensional object is described. The method may use a polymerizable liquid, or resin, useful for the production by additive manufacturing of a three-dimensional object, comprising a mixture of (i) a light polymerizable liquid first component, and (ii) a second solidifiable component that is different from said first component.

A method of forming a three-dimensional object is carried out by: (a) providing a carrier and an optically transparent member having a build surface, the carrier and the build surface defining a build region therebetween; (b) filling the build region with a polymerizable liquid, the polymerizable liquid including a mixture of (i) a light polymerizable liquid first component, and (ii) a second solidifiable component that is different from the first component; (c) irradiating the build region with light through the optically transparent member to form a solid polymer scaffold from the first component and also advancing the carrier away from the build surface to form a three-dimensional intermediate having the same shape as, or a shape to be imparted to, the three-dimensional object, and containing the second solidifiable component carried in the scaffold in unsolidified and/or uncured form; and (d) concurrently with or subsequent to the irradiating step, solidifying and/or curing the second solidifiable component in the three-dimensional intermediate to form the three-dimensional object.

Methods of printing a three-dimensional object using co-reactive components are disclosed. Thermosetting compositions for three-dimensional printing are also disclosed.

Methods of printing a three-dimensional object using co-reactive components are disclosed. Thermosetting compositions for three-dimensional printing are also disclosed.

Methods of printing a three-dimensional object using co-reactive components are disclosed. Thermosetting compositions for three-dimensional printing are also enclosed.

A thermoset composite material and composite railroad crosstie fabricated from the thermoset composite material that comprises a substantially homogeneous blend of an amount of vulcanized rubber particles, polyurea binding agent and urea melamine. The thermoset composite material may also contain a granulated silica material. The thermoset composite material may comprise about 30% to about 50% by weight of the vulcanized rubber particles, and it is subjected to compression molding at a predetermined temperature and pressure for a resident time period forming the composite railroad crosstie. The thermoset composite material and railroad crosstie may further comprise a fibrous glass material in the form of unbundled fibers and/or one more glass mats encapsulated within the thermoset composite material. In addition or alternatively, an elongated core insert may be encapsulated in the thermoset composite material.