Abstract: Disclosed are surface retarder composition and method for etching cementitious materials which achieve a desirable light “acid etch” look without using muriatic (hydrochloric) acid or sand blasting, removing the human health and environmental concerns. Formulations in accordance with embodiments disclosed herein are easier to remove from formwork or molds after demolding than conventional retarder paints. Surface retarders prevent the hydration of cement particles, which allows the uncured layer of paste next to the form to be removed such as by washing with water or other fluids, or by brushing, revealing aggregates. Also disclosed are molded cement and concrete materials or articles exhibiting such light etch.

Abstract: A self-aligning roofing shingle with a shingle body defining a top edge, and at least two spaced locating features proximate the top edge of the shingle body, each locating feature defined by a projection and an indentation, wherein a projection of one shingle in a first course of shingle locates in an indentation of a mating shingle in an adjacent course of shingles.

Abstract: A high voltage DC power distribution system that eliminates static switches and batteries. Flywheel energy storage devices and extremely reliable, high power DC/DC converters provide at a lower cost, more reliable, noise and harmonic free, critical electrical power directly at equipment racks at 48 VDC, 24 VDC, 6 VDC, 2 VDC, or any other desired DC voltage level.

Abstract: A chromium VI reducing composition comprising particles of solid material selected from the group consisting of iron (II) sulfate and tin sulfate, the particles being substantially uniformly dispersed within a liquid carrier. Methods for modifying hydratable cementitious materials using the chromium reducing composition are also disclosed and provide advantages over dry powder or dissolved forms of sulfate compositions when used in cement manufacturing.

Abstract: A gas turbine engine fan blade containment assembly (38) comprising a generally cylindrical, or frustoconical, metal casing (40) which has an inner surface (62), an outer surface (64), an upstream flange (42) and a downstream flange (52). The outer surface (62) of the metal casing (40) is provided with a pattern of blind apertures (66) which extend radially inwardly from the outer surface (62) of the metal casing (40) between the flanges (42,52). The fan blade containment has reduced weight of the metal casing (40) of the fan blade containment assembly (38) for a large diameter turbofan gas turbine engine (10) but has unimpaired stiffness and penetration resistance.

Abstract: A gas turbine engine fan blade containment assembly (38) comprising a generally cylindrical, or frustoconical, metal casing (40) which has an inner surface (62), an outer surface (64), an upstream flange (42) and a downstream flange (52). The outer surface (62) of the metal casing (40) is provided with a pattern of blind apertures (66) which extend radially inwardly from the outer surface (62) of the metal casing (40) between the flanges (42,52). The fan blade containment has reduced weight of the metal casing (40) of the fan blade containment assembly (38) for a large diameter turbofan gas turbine engine (10) but has unimpaired stiffness and penetration resistance.

Abstract: A turbofan gas turbine engine (10) comprises a fan rotor (32) carrying a plurality of radially extending fan blades (34). A fan blade containment assembly (38) surrounds the fan blades (34) and the fan blade containment assembly (34) comprises a generally annular, or frustoconical, cross-section casing (52). At least one corrugated sheet metal ring surrounds the casing (52) wherein the corrugations extend with axial and/or circumferential components.

Abstract: A gas turbine engine fan blade containment assembly (38) comprising a generally cylindrical, or frustoconical, metal casing (40) which has an inner surface (62), an outer surface (64), an upstream flange (42) and a downstream flange (52). The outer surface (62) of the metal casing (40) is provided with a pattern of blind apertures (66) which extend radially inwardly from the outer surface (62) of the metal casing (40) between the flanges (42,52). The fan blade containment has reduced weight of the metal casing (40) of the fan blade containment assembly (38) for a large diameter turbofan gas turbine engine (10) but has unimpaired stiffness and penetration resistance.

Abstract: An internet based system for generating and analysing astrological data in which numerical values representative of relationships between astrological conditions are identified and used in a calculation to determine a quantitative value for an activity type with respect to the astrological data.

Abstract: A turbofan gas turbine engine (10) comprises a fan rotor (32) carrying a plurality of radially extending fan blades (34). A fan blade containment assembly (38) surrounds the fan blades (34) and the fan blade containment assembly (38) comprises a generally cylindrical, or frustoconical, metal casing (40). The casing (40) comprises an annular hook (54) positioned axially upstream of the tip (37) of the fan blade (34). The annular hook (54) extends in a radially inwardly and axially downstream direction from the metal casing (40) towards the tip (37) of the fan blade (34). The metal casing (40) has a containment portion (A) downstream of the annular hook (54) and substantially in the plane of the leading edge of the tip (37) of the fan blade (34). The containment portion (A) of the casing (40) has a greater diameter than the diameter of the casing (40) at the annular hook (54) to restrain upstream movement of a detached fan blade (34).

Abstract: A gas turbine engine fan blade containment assembly (38) comprising a generally cylindrical, or frustoconical, metal casing (40) which has an inner surface (62), an outer surface (64), an upstream flange (42) and a downstream flange (52). The outer surface (62) of the metal casing (40) is provided with a pattern of blind apertures (66) which extend radially inwardly from the outer surface (62) of the metal casing (40) between the flanges (42,52). The fan blade containment has reduced weight of the metal casing (40) of the fan blade containment assembly (38) for a large diameter turbofan gas turbine engine (10) but has unimpaired stiffness and penetration resistance.