Abstract: A geopolymer composite binder is provided herein, the composite binder including (i) at least one fly ash material having less than or equal to 15 wt % of calcium oxide; (ii) at least one gelation enhancer; and (iii) at least one hardening enhancer having a different composition from a composition of the at least one fly ash material.

Abstract: Three pumpable geopolymer compositions for well sealing application is disclosed herein. One pumpable geopolymer composition comprises: (i) less reactive aluminosilicate; (ii) more reactive aluminosilicate; (iii) alkaline silicate activator solution with a very low SiO2/M2O. Another pumpable geopolymer composition comprises: (i) less reactive aluminosilicate; (ii) more reactive aluminosilicate; (iii) alkaline silicate-free activator solution that may contain an alkali salt; and (iv) powdered alkali silicate glass. The third pumpable geopolymer composition comprises (i) less reactive aluminosilicate; (ii) more reactive aluminosilicate; (iii) alkaline low silicate activator solution; and (iv) powdered alkali silicate glass.

Abstract: An engine assembly includes an engine control unit, an internal combustion engine having an exhaust, a turbine driven in use by said exhaust, and an energy storage mechanism for storing energy recovered from said exhaust by said turbine, wherein the engine control unit is operable to vary the rate of storing energy in the energy storage mechanism.

Abstract: A geopolymer composite binder is provided herein, the composite binder including (i) at least one fly ash material having less than or equal to 15 wt % of calcium oxide; (ii) at least one gelation enhancer; and (iii) at least one hardening enhancer having a different composition from a composition of the at least one fly ash material.

Abstract: A geopolymer composite ultra high performance concrete (GUHPC), and methods of making the same, are provided herein, the GUHPC comprising: (a) a binder comprising one or more selected from the group consisting of reactive aluminosilicate and reactive alkali-earth aluminosilicate; (b) an alkali activator comprising an aqueous solution of metal hydroxide and metal silicate; and (c) one or more aggregate.

Abstract: An engine assembly includes an engine control unit, an internal combustion engine having an exhaust, a turbine driven in use by said exhaust, and an energy storage mechanism for storing energy recovered from said exhaust by said turbine, wherein the engine control unit is operable to vary the rate of storing energy in the energy storage mechanism.

Abstract: A geopolymer composite ultra high performance concrete (GUHPC), and methods of making the same, are provided herein, the GUHPC comprising: (a) a binder comprising one or more selected from the group consisting of reactive aluminosilicate and reactive alkali-earth aluminosilicate; (b) an alkali activator comprising an aqueous solution of metal hydroxide and metal silicate; and (c) one or more aggregate.

Abstract: Provided in one embodiment is a method of charactering a fly ash composition, comprising determining a reactivity of the fly ash composition in a solution. The applicability of the findings to low water-to-solid ratios for the process of geopolymerization for the relationship between the amounts of fly ash reacted, and the compressive strength of a geopolymer cement is also described.

Abstract: An optical network comprises a transmitter node (1), a receiver node (4) and an optical fiber (3) for transmitting an optical wavelength-division multiplex signal having payload channels and a supervisory channel between the nodes (1, 4). At least one of the nodes has an amplifier (8, 13) which is passed by the multiplex signal. The transmitter node (1) has a source (11) for the supervisory channel and a multiplexer (12) for combining the payload channels and the supervisory channel in order to form the optical wavelength-division multiplex signal, and the receiver node (4) has a sink (16) for the supervisory channel and a demultiplexer (14) for separating the wavelength division multiplex signal into supervisory and the payload channels.

Abstract: A component for an optical communication network comprises a source (6) for an optical communication signal, an output port (11) for outputting the optical communication signal on an optical transmitting fiber (1), a light sensor (14; 15) and an optical circulator (9) for transmitting the optical communication signal from the source (6) to the output port (11) and for transmitting light reflected or received from outside at the output port (11) to the light sensor (14; 15). The light sensor (14, 15) has an evaluation circuit (13) connected to it for detecting a time delay between a time marker of a light signal from the source and the corresponding time marker of the light arriving at the light sensor (14; 15).

Abstract: A cooling system for an internal combustion engine 1 is disclosed in which an electronically controlled flow control valve 9 is used to control the flow of coolant exiting the engine 1. The electronically controlled flow control valve 9 is able to control the cooling of the engine 1 irrespective of the speed at which a pump 2 used to urge coolant to flow into the engine 1 is rotated by a drive belt 3 connected to an output 4 from the engine 1.

Abstract: An internal combustion engine is provided having at least one cylinder bore for slidingly supporting a piston, the cylinder bore wall of the at least one cylinder of the engine having pockets formed therein for retaining lubricant to reduce friction between the cylinder bore wall and piston. The pockets are elongate and have axes which are substantially parallel to the axis of the cylinder bore. The pockets are located at a first region supporting the piston when the piston is at its top dead center position. A method of making the cylinder is also provided.

Abstract: A variable displacement internal combustion engine having selectively disabled cylinders, the engine including two turbochargers each having a turbine and a compressor, an exhaust system connecting the turbines of both turbochargers to all the engine cylinders, and valving within the exhaust system for selectively directing exhaust gases to flow through one, the other or both turbocharger exhaust turbines, the valving being controlled in dependence upon the number of deactivated cylinders.

Abstract: Treatment of a radioactive waste stream is provided by adding sodium hydroxide (NaOH) and/or potassium hydroxide (KOH) together with a rapidly dissolving form of silica, e.g., fumed silica or fly ash. Alternatively, the fumed silica can be first dissolved in a NaOH/KOH solution, which is then combined with the waste solution. Adding a binder that can be a mixture of metakaolin (Al2O3.2SiO2), ground blast furnace slag, fly ash, or other additives. Adding an “enhancer” that can be composed of a group of additives that are used to further enhance the immobilization of heavy metals and key radionuclides such as 99Tc and 129I. An additional step can involve simple mixing of the binder with the activator and enhancer, which can occur in the final waste form container, or in a mixing vessel prior to pumping into the final waste form container, depending on the particular application.

Abstract: A cooling system for an internal combustion engine is disclosed in which the supply of coolant to a cylinder block 6 is controlled independently of the coolant supply to a cylinder head 10 so that the temperatures of the cylinder block 6 and the cylinder head 10 can be optimised to produce improved performance and economy.

Abstract: A cooling system for an internal combustion engine 1 is disclosed in which an electronically controlled flow control valve 9 is used to control the flow of coolant exiting the engine 1. The electronically controlled flow control valve 9 is able to control the cooling of the engine 1 irrespective of the speed at which a pump 2 used to urge coolant to flow into the engine 1 is rotated by a drive belt 3 connected to an output 4 from the engine 1.

Abstract: An L-band EDFA may have three amplifier stages. In the first stage, a high power 980 nm laser is used to generate C-band ASE noise which is used to pump the erbium doped fiber of the second stage. The second stage fiber is arranged as a plug-in module which connects between a first stage isolator and a mid-stage loss between the second and third stages. The desired gain of the amplifier is obtained by selecting a plug-in module with a length of fiber that will give the desired amplifier output power for a given input power.