Abstract: An exhaust treatment system associated with a power source is disclosed. The exhaust treatment system may have a filter located to remove particulate matter from an exhaust flow of the power source. The exhaust treatment system may further have a heat source located to elevate the temperature of the exhaust flow. The exhaust treatment system may also have a first sensor and a second sensor. The exhaust treatment system may further have a controller in communication with the heat source, the first sensor, and the second sensor. The controller may be configured to receive a particulate matter load value and a power source load value and activate the heat source when the particulate matter load value is above a particulate matter load threshold value and the power source load value is below a power source load threshold value that is indicative of the exhaust flow being within an exhaust flow range.

Abstract: Various embodiments of an apparatus, system, and method are disclosed for reducing NOx emissions using ammonia storage on an SCR catalyst. For example, according to one representative embodiment, an apparatus for reducing NOx emissions in an engine exhaust includes a NOx reduction target module that is configured to determine a NOx reduction requirement. The apparatus also includes an ammonia storage module that is configured to determine an ammonia storage modifier. An ammonia target module of the apparatus is configured to determine an ammonia addition requirement. The ammonia target module is communicable in data receiving communication with the ammonia storage module to receive the ammonia storage modifier, which is added to the ammonia addition requirement. The apparatus also includes a reductant target module that is configured to determine a reductant injection requirement that includes an amount of reductant added to the exhaust gas stream to achieve the ammonia addition requirement.

Abstract: Various embodiments of an apparatus, system, and method are disclosed for reducing NOx emissions on an SCR catalyst. For example, according to one representative embodiment, an apparatus for reducing NOx emissions in an engine exhaust includes a NOx reduction target module that is configured to determine a NOx reduction requirement that includes an amount of NOx in the exhaust gas stream to be reduced on a selective catalytic reduction (SCR) catalyst. The apparatus also includes an ammonia target module that is configured to determine an ammonia addition requirement that includes an amount of ammonia added to the exhaust gas stream to achieve the NOx reduction requirement. The apparatus also includes a reductant target module that is configured to determine a reductant injection requirement that includes an amount of reductant added to the exhaust gas stream to achieve the ammonia addition requirement.

Abstract: The present invention relates to an exhaust gas treatment unit for an exhaust system of a combustion engine, in particular of a motor vehicle, includes a housing, a plurality of exhaust gas treatment elements, which are arranged in the housing and through which a parallel flow is possible. The unit further includes an outlet nozzle, which penetrates a side face of the housing, and an outlet space disposed in the housing, whereby the outlet of at least one of the exhaust gas treatment elements opens into the outlet space. The rigidity and/or effectiveness of the exhaust gas treatment unit can be improved by means of a funnel body disposed in the outlet space, and comprising a funnel surface which is permeable to exhaust gas. The funnel body connects an outlet end of one of the exhaust gas treatment elements with the outlet nozzle.

Abstract: An exhaust gas control apparatus (2) for an engine includes a filter case (3) that has an internal space; a filter (4) that is arranged in the filter case (3) and that purifies exhaust gas; and a mat (5) that is arranged, in a compressed state, between the filter case (3) and the filter (4). The filter (4) is arranged in the filter case (3) with a first flange (45) of the filter (4) engaged with the mat (5) and with a second flange (46) engaged with a retainer (6).

Abstract: The invention relates to an automotive drive train having an internal combustion engine (266) that is configured as a three-cylinder engine and a hydrodynamic torque converter device. Said device has a torsional vibration damper consisting of two energy accumulating devices (272, 276) and a converter lockup clutch (268). The turbine wheel (274) is interposed between the two energy accumulating devices (272, 276). According to the invention, ranges of values or ratios for the following parameters are claimed: maximum engine torque Mmot,max (266), spring rate c1 (272), mass moment of inertia J1 (274), spring rate c2 (276), mass moment of inertia J2 (278) and spring rate cGEW of the transmission input shaft (280). The mass moment of inertia J1 should be high between the two energy accumulating devices (272, 276) and masses should be as little as possible between the torsional vibration damper and the transmission input shaft. FIG.

Abstract: A machine, such as a backhoe, has a series of components connected in series and moved by separate hydraulic actuators. A position estimator determines the present position of each component from the load acting on the associated hydraulic actuator and a velocity command for the component. For each component, a function parameter estimator uses the present positions of the components to derive a set of parameters that include a static structure load that the components exert on the associated hydraulic actuator, acceleration and deceleration limits for both directions of component motion, and a control bandwidth for the associated hydraulic actuator. The set of parameters for a given component is used to control the associated hydraulic actuator.

Abstract: A backup system is provided that has a local electric motor and pump for some or all of hydraulic actuators. A local backup hydraulic actuator has two power sources, hydraulic as primary and electrical as backup. During normal operation, the hydraulic actuator receives pressurized fluid from a hydraulic system and the fluid flow to the chambers is controlled by a servo valve. If the hydraulic system fails, the electronic controller detects the failure by observing the signal indicative of the pressure from the pressure sensor, and the controller powers the local hydraulic pump to provide high pressure hydraulic fluid to the hydraulic actuator via the servo valve.

Abstract: A Stirling engine mounted on a vehicle to efficiently absorb and accumulate the kinetic energy of the vehicle at the time of braking, to improve fuel economy during traveling of the vehicle and to increase the braking effect of an engine brake. The Stirling engine for driving the vehicle is provided with an operating condition-changing device which, at the time of braking the vehicle, changes the operating condition of the Stirling engine over to the heat pump operation. The Stirling engine having, for example, two pistons is provided with the phase difference-changing mechanism 6 for changing a relative phase of the piston 1 and the piston 2. When the brake is applied, the phases of the two pistons are changed to effect the heat pump operation using the power from drive wheels of the vehicle. Heat accumulators 5H and 5C are installed in a heating portion 12 and a cooling portion 22 of the Stirling engine.

Abstract: A variable nozzle for a turbocharger includes a plurality of vanes rotatably mounted on a nozzle ring and disposed in a nozzle flow path defined between the nozzle ring and an opposite nozzle wall. Either or both of the faces of the nozzle ring and nozzle wall include(s) at least one step that defines sealing surfaces positioned to be substantially abutted by airfoil surfaces of the vanes in the closed position of the vanes and to be spaced from the airfoil surfaces in positions other than the closed position. This substantial abutment between the airfoil surfaces and the sealing surfaces serves to substantially prevent exhaust gas from leaking past the ends of the airfoil portions. At the same time, clearances between the nozzle ring face and the end faces of the airfoil portions can be sufficiently large to prevent binding of the vanes under all operating conditions.

Abstract: Heat recovery equipment recovers heat from flue gas. The heat recovery equipment includes a power generation plant that drives a steam turbine by superheated steam produced in a boiler, and an exhaust-gas treatment line that treats flue gas output from the boiler. The exhaust-gas treatment line includes a first air preheater, a heat extractor unit, and a dry electrostatic precipitator. The power generation plant includes a condensed water line. The condensed water line includes a condenser, a condensed water heater, and a low-pressure feedwater heater. The condensed water heater heats water condensed by the condenser with the heat recovered by the heat extractor unit.

Abstract: Heat recovery equipment recovers heat from flue gas. The heat recovery equipment includes a power generation plant that drives a steam turbine by superheated steam produced in a boiler, and an exhaust-gas treatment line that treats flue gas output from the boiler. The exhaust-gas treatment line includes a first air preheater, a heat extractor unit, and a dry electrostatic precipitator. The power generation plant includes a condensed water line. The condensed water line includes a condenser, a condensed water heater, and a low-pressure feedwater heater. The condensed water heater heats water condensed by the condenser with the heat recovered by the heat extractor unit.

Abstract: A method and installation are provided for reduction of natural gas from high pressure, such as in a borehole or in a main pipeline down to the pressure valve required for the consumer.

Abstract: An axially staged combustion system is provided for a gas turbine engine comprising a main body structure having a plurality of first and second injectors. First structure provides fuel to at least one of the first injectors. The fuel provided to the one first injector is adapted to mix with air and ignite to produce a flame such that the flame associated with the one first injector defines a flame front having an average length when measured from a reference surface of the main body structure. Each of the second injectors comprising a section extending from the reference surface of the main body structure through the flame front and having a length greater than the average length of the flame front. Second structure provides fuel to at least one of the second injectors. The fuel passes through the one second injector and exits the one second injector at a location axially spaced from the flame front.

Abstract: The invention relates to a burner, in particular a gas turbine burner, comprises: at least one swirler, the swirler having at least one air inlet opening, at least one air outlet opening positioned downstream to the air inlet opening and at least one swirler air passage extending from the at least one air inlet opening to the at least one air outlet opening which is delimited by swirler air passage walls, the air passage walls comprising downstream wall sections adjoining the at least one air outlet opening; and a fuel injection system which comprises fuel injection openings arranged in at least one swirler air passage wall so as to inject fuel into the swirler air passage; in which at least the downstream section of one air passage wall is corrugated.

Abstract: The present application provides a method of operating a dual gas fuel delivery system comprising selecting a manifold and fuel flow split; setting the stroke of a high-energy gas control valve based on the fuel split; measuring the primary manifold nozzle pressure ratio across a primary manifold nozzle outlet; comparing the primary manifold nozzle pressure ratio against a primary manifold specification limit; adjusting the stroke of a primary low energy gas control valve to maintain the pressure ratio across the primary manifold nozzle outlet within the primary manifold specification limit; measuring the secondary manifold nozzle pressure ratio across a secondary manifold nozzle outlet; comparing the secondary manifold nozzle pressure ratio against a secondary manifold specification limit; and adjusting the stroke of a secondary low energy gas control valve to maintain the pressure ratio across the secondary manifold nozzle outlet within the secondary manifold specification limit.

Abstract: Provided herein are, among other things, jet fuel compositions and methods of making and using the same. In some embodiments, the fuel compositions comprise at least a fuel component readily and efficiently produced, at least in part, from a microorganism. In certain embodiments, the fuel compositions provided herein comprise a high concentration of at least a bioengineered fuel component. In further embodiments, the fuel compositions provided herein comprise amorphane.

Abstract: The invention relates to a gas turbine, for energy generation, with a compressor, arranged coaxially to a rotor, mounted such as to rotate, for the compression of an inlet gaseous fluid, at least partly serving for combustion of a fuel in a subsequent annular combustion chamber, with generation of a hot working medium, with an annular diffuser arranged coaxially to the rotor, between the compressor and the annular combustion chamber, for distribution and deflection of the fluid, whereby a part of the fluid is diverted as cooling fluid for the turbine stages after the combustion chamber, by means of a dividing element, arranged in the fluid flow.

Abstract: A gas turbine aircraft engine with power variability is provided. The gas turbine aircraft engine comprises a compressor and a turbine mounted on a common shaft, and, a continuously variable transmission coupled to the shaft for transmitting power to a propulsion load.

Abstract: A shroud suitable for use in a gas turbine engine exhibits substantially uniform thermal growth.

Abstract: Gas turbine engine systems and related methods involving thermally isolated retention are provided. In this regard, a representative method for attaching a gas turbine engine component includes using a fastener, varying in diameter along a length thereof, to prevent a portion of a component from being crimped between surfaces to which the component is attached such that the component moves relative to the surfaces responsive to thermal cycling of a gas turbine engine of which the surfaces and the component are constituent parts.

Abstract: The invention relates to a cooling channel for a component conveying hot gas for the purposes of conveying a coolant along a direction of flow with a dowrnstream and an upstream side, with a plurality of inlet apertures for a coolant, with a number of inlet apertures that vary their configuration at least partly among themselves is arranged at least in one section of the cooling channel. As a result, the heat-transfer coefficient is substantially increased at points particularly requiring cooling and therefore the cooling is substantially improved. The cooling channel is characterized by a particularly low pressure loss.

Abstract: A voltage regulator is configured to receive an input voltage from a power supply, measure a temperature associated with a heat transfer medium, produce an output voltage to drive a thermo-electric cooler, and vary the output voltage in accordance with changes in the measured temperature. Varying the output voltage results in: 1) extracting of heat from the heat transfer medium when the measured temperature is above a threshold value, or 2) supplying of heat to the heat transfer medium when the measured temperature is below a threshold value. The voltage regulator can cap upper and lower bounds of the output voltage to prevent the thermo-electric cooler from reaching its saturation point. The voltage regulator can be configured to produce an output voltage having reduced voltage ripple.

Abstract: The present application is directed to methods and systems for transporting or importing LNG via vessels. Under the present techniques, SRTs, which are equipped with regasification equipment, LNG offloading equipment (e.g. marinized mechanical loading arms), LNG storage tanks, and equipment to transfer natural gas to an import terminal are utilized as temporary interchangeable FSRUs (TIFs). Two or more TIFs in conjunction with transport vessels (e.g. LNGCs) are utilized to transfer LNG between an export terminal and an import terminal. A first of the TIFs is utilized at an import terminal to offload LNG from LNGCs, while the second of the TIFs is utilized as a LNGC, carrying LNG between the export terminal and import terminal. The first of the TIFs may be replaced by the second of the TIFs to maintain operations for the import terminal.

Abstract: A system and method to connect a cryocooler (refrigerator) to a superconducting magnet or cooled object allows for replacement without the need to break the cryostat vacuum or the need to warm up the superconducting magnet or other cooled object. A pneumatic or other type of actuator establishes a thermo-mechanical coupling. The mechanical closing forces are directed perpendicular (cross-axially) to the cryocooler axis and are not applied to the thin wall cryocooler body or to the thin cryostat walls or to the cooled object or to its shield. It is also possible that some of the compressive force be transferred to the cryocooler body. In that case, the extensions are designed so that the forces transferred to the cryocooler thermal stages do not exceed allowable stresses in the cryocooler stage.

Abstract: A cascade refrigeration system, which comprises a top cycle that circulates a first refrigerant, a low cycle that circulates a second refrigerant, and a heat exchanger through which the two cycles interface. The system further comprises a second heat exchanger through which the second refrigerant is superheated by the first refrigerant, while the first refrigerant is simultaneously subcooled by the second refrigerant. The system further comprises a control system that can regulate the amount of superheating of the second refrigerant.

Abstract: Systems and methods for cooling electrical components of an electrical submersible pump in a subterranean well are disclosed. Cooling fluid is delivered from a location proximate ground surface through a conduit to a submerged electrical pump motor in a subterranean well to cool the submerged electrical pump motor.

Abstract: An ice detecting apparatus for a refrigerator comprising and ice maker, a storage container to collect ice from the ice maker, and an ice detecting sensor provided at the ice maker including a transmitting unit to transmit one or more pulses, and a receiving unit to detect the pulses transmitted from the transmitting unit. A controller to determine whether the storage container is full or nearly full based on the pulses detected by the receiving unit among one or more pulses transmitted by the transmitting unit.

Abstract: A method for using refrigerant to check for a leak in a refrigerant system is provided that establishing fluid communication between a refrigerant recovery unit and a refrigerant system. The refrigerant recovery unit passes a refrigerant through the refrigerant recovery unit, compresses the refrigerant utilizing the refrigerant recovery unit, and transfers the compressed refrigerant from the refrigerant recovery unit directly into the refrigerant system. Additional refrigerant is added into the refrigerant system until a desired system pressure is reached, and then the refrigerant system is checked for leaks.

Abstract: A method or apparatus of accessing data includes detecting at least one parameter of a component of a refrigerated container and providing data relating to the at least one parameter to a transmitting computer located on the refrigerated container. The method or apparatus can further include transferring the data from the transmitting computer to a first remote computer located at an off-site location and transferring the data from the first remote computer to a second remote computer located at another off-site location.

Abstract: The invention pertains to a method and apparatus for removing ice layers and/or snow layers and/or dirt layers from the rotor blades of axial fans in cooling installations for refrigerating and/or freezing products. At least one cleaning substance jet is directed toward the rotor blades of an axial fan within certain time intervals in such a way that ice layers and/or snow layers and/or dirt layers are at least separated from the surfaces of the rotor blades and transported away, wherein the rotor blades rotate with nominal speed while cleaning jets act upon their surfaces.

Abstract: An absorptive refrigeration method that employs a refrigerant comprising one or more hydrofluoroolefin or hydrochlorofluoroolefin refrigerants, and an oil selected from the group consisting of a polyalkyene glycol oil, a poly alpha olefin oil, a mineral oil and a polyolester oil.

Abstract: An air conditioner refrigerant circuit performs a cooling operation in which an outdoor heat exchanger functions as a condenser of the refrigerant compressed in a compressor and an indoor heat exchanger functions as an evaporator of the refrigerant condensed in the outdoor heat exchanger. Further, an outdoor expansion valve is disposed at a position that is at once downstream of the outdoor heat exchanger and upstream of a liquid refrigerant communication pipe in the refrigerant flow direction in the refrigerant circuit in the cooling operation, and shuts off the refrigerant flow. A refrigerant detection unit is disposed upstream of the outdoor expansion valve and detects the amount or the amount-related value of refrigerant accumulated upstream of the outdoor expansion valve.

Abstract: A domestic appliance includes an interior that can be illuminated by a light source and is surrounded by walls and a door, wherein the interior is illuminated by the light source from the direction of the door, in particular wherein the door has at least one glass area, light from the light source is coupled into the glass area from the direction of an edge, with the result that the light is at least partially guided in the glass area, and the glass area has elements through which some of the light which is guided in the glass area is conducted into the interior. This manner of illumination prevents articles in the interior from having a silhouetted appearance.

Abstract: A heating/cooling system design enabling one to maintain a superheat level of more than 1 degree F. and up to 10 degrees F., incorporating a specially designed accumulator, optional special oil return means, a specially designed receiver, and, when utilized in a DX geothermal system application, a preferable sub-surface liquid refrigerant transport line insulation design, as well as a design enabling the utilization of at least two compressors to increase heat transfer temperature differentials together with special oil separators.

Abstract: A condensate evaporation device for a refrigerator is provided. The condensate evaporation device includes a refrigerant pipe and a protecting tube. The refrigerant pipe through which the refrigerant flows is installed near bottom of a pan containing condensate that flows out of the storage space so as to be immersed in the condensate. The protecting tube is disposed around at least a part of the refrigerant pipe. The protecting tube surrounds at least a part of the refrigerant pipe that is immersed in the condensate in the pan, such that the condensate does not contact and erode the refrigerant pipe directly. The protecting tube may surround the refrigerant pipe tightly to provide heat exchange between the refrigerant and the condensate via the refrigerant pipe and the protecting tube.

Abstract: In one embodiment, a floor pan assembly for use with an evaporative cooler structure includes a base that has a first height and includes a plurality of preformed first members that are located at select locations around a bottom edge of the base. The assembly also has at least one shim member that intimately engages one of the preformed first members to locally increase the height of the base relative to a ground surface. An upper floor pan is disposed above the base and includes a floor and side walls that define an interior space for collecting fluid, the upper floor pan including at least one drain port.

Abstract: A built-in refrigerator comprising a carcass, in the lower rear area of which a machine compartment is formed. Said machine compartment is closed at least in part by means of a rear wall. The rear wall delimits a first air passage of the machine compartment at the level of a support area of the carcass.

Abstract: An ice maker comprises a frame (15) and a tray (1) pivotable in the frame (15) about an axis. The tray (1) has a plurality of compartments (4) which are arranged in a number of rows and separated from one another by partition walls (3) and is pivotable between an upright setting in which the upper edges of the partition walls (3) extend horizontally, an emptying setting in which the openings of the compartments (4) face downwardly and a tilted setting in which a predetermined water quantity filled into a row of the tray (1, 1?, 1?) in part floods over the upper edges of the partition walls (3) between the compartments (4) of the row whilst after pivotation back into the upright setting the partition walls (3) separate the part quantities, which are distributed to the compartments (4), of the water quantity from one another.

Abstract: A refrigerating device, in particular a refrigerator and/or a freezer cabinet, comprising a heat-insulating housing and a heat-insulating door. At least one component is provided on or in the door, said component being fluidically and/or electrically connected by means of a line to at least one element which is arranged on the housing. The door is articulated to the housing by means of a multilink hinge. A support, which supports the line when the door is open, is provided in the intermediate area between the door and the housing. The invention is characterised in that the inner chamber of the refrigerating device can be almost completely accessed, when a water dispensing unit is provided on the door and even with solid doors.

Abstract: An improved computer cooling apparatus includes: at least one evaporator installed on a surface of at least one heat generating source which is a central processing unit in a computer system unit; a compressor, connected to the evaporator; a condenser, connected to the compressor; an expansion valve, connected between the condenser and the evaporator; a fan, installed on a side of the condenser; and a coolant, circulating among the evaporator, the compressor, the condenser and the expansion valve. The evaporator, compressor, condenser, fan, expansion valve and coolant are used for achieving the effect of quickly dispersing a heat generating source in the computer system unit.

Abstract: An improved computer cooling apparatus includes: a heat absorbing unit, having at least one water cooling block, a pump connected to the water cooling block, and a heat exchanger connected to the pump, and a first working fluid flows through the water cooling block, the pump and the heat exchanger; and a cooling unit, having an evaporator attached onto the heat exchanger, a compressor connected to the evaporator, a condenser connected to the compressor, and an expansion valve connected to the condenser, and a second working fluid flows through the evaporator, the compressor, the condenser and the expansion valve. The heat absorbing unit absorbs a related heat source in a computer, and a cooling unit dissipates the heat to provide a quick way of dispersing the heat source and a better heat dissipating effect.

Abstract: The present invention concerns a cooling or heating system including at least a compressor (10), a coolant tank/accumulator (4), a condenser (11), an inspection glass device with ejector pump (1, 2) for circulation and control of coolant, coolant and a vaporiser (13). The invention is characterised essentially in that the system comprises: a connection (8) to the ejector pump (1, 2), for intake of condensate from the condenser (11), an exit connection (9) from the ejector pump (1, 2), for connection to the vaporiser (13) and means (3) for visually controlling the ejector pump (1, 2). The invention also concerns a device (12) for controlling the coolant of a cooling or heating apparatus.

Abstract: A piece of jewelry to be worn by a wearer, having a spray mechanism mounted on the piece of jewelry, and a reservoir for containing a fluid mounted on the piece of jewelry, to dispense a fluid, such as a fragrance or scent, to the body of the wearer. The manipulation of the reservoir by the wearer actuates the spray mechanism and dispenses fluid from the reservoir.

Abstract: A low cost, crimpless method of stringing beads and article thereof. The method employs tight knots and twists in small diameter, triple strand nylon coated high toughness and high tensile strength austenitic stainless steel wire to retain clasps and position beads and jewels on the wire. The method is dependent upon the size and physical properties of the wire. It improves appearance, eliminates the use of crimping beads and tubes, does not require special tools and is adaptable to right handed, left handed and visually impaired persons.

Abstract: A decorative article such as a bracelet is formed from one or more elastomeric cords and one or more braiding cords. Generally, the elastomeric cords provide a structure around which one or more braiding cords may by arranged, and upon which one or more decorative elements may be threaded. The elastomeric cords allow decorative elements, such as buttons, to be secured to the top surface of a decorative bracelet. In addition, the elastomeric cords allow the bracelet to have a more customized fit and increased durability. The braiding cords are woven around the elastomeric cords, such as in knots. A clasp may be formed from the elastomeric cords. The clasp may accept one or more decorative elements to secure the bracelet in a loop configuration.

Abstract: Disclosed are systems and methods for scoring and separating a glass sheet along a curved trajectory using a laser and optics. The system includes a laser that generates a laser beam, a focusing lens, and a conical optical component such as a conical lens or a reflective conical milTor. The laser directs the laser beam through the focusing lens and conical lens to create a curved score line that is projected onto a glass sheet to create a curved score line, along which the glass sheet can be separated. Optionally, the laser directs the laser beam through the focusing lens towards a conical mirror, off of which the laser beam is reflected toward the glass sheet to create a curved score line.

Abstract: A cradle for a high-temperature fluid delivery system, comprising a shell including a base and two side walls defining a trough, wherein the shell comprises fused zirconia. Fused zirconia provides the high temperature creep-resistance, corrosion resistance and thermal insulation to supported delivery system. The cradle extends system life, increases product quality and reduces costs associated with failure of glass delivery system.

Abstract: A pulling roll for glass manufacture made of a high-temperature millboard material. The millboard includes aluminosilicate refractory fiber, silicate, mica, and kaolin clay. A method of manufacturing a pulling roll also is disclosed, together with a roll produced by the methods disclosed herein. The method includes forming a pulling roll and densifying at least a portion of the pulling roll by exposing the pulling roll to high temperatures.

Abstract: The present invention provides a method for manufacturing an optical fiber comprising the steps of forming a glass body containing a core, preparing a glass tube which will form a cladding portion, inserting the glass body into the glass tube, and collapsing the glass tube with the glass body by heating, wherein the method comprises a step of processing the glass tube such that it has at least one end tapered to which a pull is to be applied. The method may further comprise the steps of cleaning the outer surface of the glass tube, choosing the outer diameter of the glass body and the inner diameter of the glass tube such that the difference between the two diameters is not lower than 1.0 mm but not higher than 10.