![]() PROPELLER ASSEMBLY OF AN AIRCRAFT COMPRISING A GAS GENERATOR AND TWO BLOWERS DEPORTEES
专利摘要:
The invention relates to a propulsion unit (10) for an aircraft, comprising a single gas generator (11) and two blowers (12) rotated by the gas generator (11) and deported on both sides a vertical plane passing through a longitudinal axis (X) of the gas generator, the axes of rotation of the fans extending substantially in the same plane of blowers. According to the invention, the propulsion assembly (10) comprises an air intake fairing (15) formed upstream of a nacelle (25) connecting the blowers, said fairing (15) having between the blowers (12) an air inlet opening (17) extending substantially perpendicularly to the plane of blowers and on either side of this plane, the propulsion assembly further comprising a device for supplying air configured to supply the gas generator (11) with a portion of the incoming air and to draw in the remaining portion of the incoming air a flow of cooling air for cooling elements of the propulsion assembly and / or a wing supporting the propulsion unit. 公开号:FR3043653A1 申请号:FR1560904 申请日:2015-11-13 公开日:2017-05-19 发明作者:Philippe Gerard Chanez;Mathieu Patrick Jean-Louis Lallia;Christian Sylvain Vessot 申请人:SNECMA SAS; IPC主号:
专利说明:
Propulsion unit for an aircraft comprising a gas generator and two remote blowers 1. Field of the invention The present invention relates to the aeronautical field and aims a propulsion assembly comprising at least two blowers driven by a gas generator. 2. State of the art New propulsion assembly architectures comprising at least two remote blowers with respect to a gas generator, most often under the wings of an aircraft, have been proposed to optimize the propulsive efficiency thanks to a high dilution rate or BPR. (for the English designation "Bypass Ratio") while maintaining an acceptable ground clearance and small blowers. The dilution ratio is the ratio between the flow of secondary flow or cold flow through the blower or blowers to generate a thrust and a primary flow or hot flow through the gas generator. Such an architecture provides that the blowers and the gas generator are each arranged in casings more or less contiguous to each other. These housings extend downstream with reference to the flow of gas in the propulsion assembly and the housing of the gas generator is arranged astride the fan casings. Due to the off-axis blowers on the sides of the gas generator, and since the air inlet thereof is disposed in a restricted space between the two blower housings, this space generates a sonic flow, or even supersonic which involves a strong drag altering the performance of the power package. Another disadvantage of this architecture lies in the fact that the air inlet of the gas generator is likely to ingest particles also called foreign bodies such as sand, hail, birds, or others. 3. Objective of the invention The present invention aims to provide a set of propulsion including reducing aerodynamic drag. 4. Presentation of the invention This objective is achieved in accordance with the invention by means of a propulsion assembly of an aircraft, comprising a single gas generator and two blowers rotated by the gas generator and offset on either side of a plane. vertical passing through a longitudinal axis of the gas generator, the axes of rotation of the blowers extending substantially in the same plane of blowers, the propulsion assembly comprising an air intake fairing formed upstream of a nacelle connecting the blowers, said fairing having between the blowers an air inlet opening extending substantially perpendicularly to the plane of blowers and on either side of this plane, the propulsion assembly further comprising a cooling device; an air supply configured to supply the gas generator with a portion of the incoming air and to draw a flow of air into the remaining portion of the incoming air cooling device for cooling elements of the propulsion assembly and / or a wing supporting the propulsion assembly. Thus, this solution achieves the aforementioned objective. The fact of having a ducted air intake, part of a nacelle connecting the two blowers, between the restricted space between the two blowers makes it possible to fill this space or inter-blowing zone subject to strong Machs. This configuration also makes it possible to feed the gas generator while cooling the latter and / or adjacent equipment while penalizing aerodynamic drag as little as possible. According to one characteristic of the invention, the longitudinal axis of the gas generator passes inside the air inlet opening. According to another characteristic of the invention, the blowers have air inlet lips defined in the same plane. According to another characteristic of the invention, the blowers have air inlet lips defined in axially offset and substantially parallel planes. In this way, in a typical configuration where the leading edge of the wing has an arrow with the axis of the fuselage, this arrangement allows a fair distribution of the flow between the inner and outer blowers, particularly during a phase of flight. ascent of the aircraft, avoiding that the incident air entering the blowers is impeded by the leading edge of the wing. Advantageously, but not exclusively, the air inlet opening is situated substantially in the same plane as that defined by the air intake lip of the fan furthest downstream. According to another characteristic of the invention, the air inlet opening is formed in a single part. According to one embodiment of the invention, the air inlet opening is formed of two parts distributed on either side of the fan plane and separated from each other by a wall. According to another characteristic of the invention the air inlet opening or the two air inlet openings is (are) bent (es). This bending makes it possible to adapt to the walls of blowers generally of circular section. According to another characteristic of the invention, the air inlet opening has a symmetry with respect to a vertical plane passing through the longitudinal axis of the gas generator. According to yet another characteristic of the invention, the longitudinal axis of the gas generator is located above the fan plane, and the air supply device comprises an air inlet sleeve feeding the generator of gas, said inlet duct having upstream an inlet duct having an opening located substantially under the plane of blowers. According to yet another characteristic of the invention, the air supply device comprises a ventilation duct situated essentially above the fan plane and from which the flow of cooling air is taken. The invention also relates to an aircraft wing supporting a propulsion assembly according to any one of the above-mentioned characteristics. 5. BRIEF DESCRIPTION OF THE FIGURES The invention will be better understood, and other objects, details, features and advantages thereof will become more clearly apparent on reading the following detailed explanatory description of embodiments of the invention. invention given by way of purely illustrative and non-limiting examples, with reference to the appended diagrammatic drawings in which: FIG. 1 shows a partial front view of an aircraft wing supporting a propulsion unit according to the invention; Figures 2 to 4 are views from below of a wing to which is hung a propulsion assembly, the blowers and the gas generator are arranged according to different embodiments; Figure 5 is a perspective view of a wing supporting a propulsion assembly according to another embodiment of the invention; Figure 6 is a schematic representation of another embodiment of the propulsion assembly according to the invention; Figure 7 is a cross-sectional and diagrammatic view of a propulsion assembly hung under a wing according to another embodiment; and, Figure 8 is a cross-sectional and schematic view of a propulsion assembly according to the invention, showing an embodiment of the air supply device. 6. Description of embodiments of the invention FIG. 1 is a partial view of one of the propulsive wings or lateral wings 1 of lift of an aircraft, and in particular of an aircraft (not represented), implanted in a fuselage of the aircraft. This wing 1 extends in a direction of E-E span from the fuselage and comprises an upper surface 2 said extrados and a lower surface 3 said intrados opposite to a plane comprising the E-E span direction. The intrados and extrados surfaces 2, 3 are connected to each other by a leading edge 4 upstream and a trailing edge 5 downstream of the wing. In the present invention the terms "upstream" and "downstream" are defined relative to the direction of travel of the aircraft. A propulsion assembly 10 supported by each propulsive wing 1 comprises a gas generator 11 of longitudinal axis X substantially parallel to the axis of elongation of the fuselage and two blowers 12 of axes offset relative to a vertical plane passing through the axis of the gas generator. The blowers are arranged on either side of the gas generator. Preferably, but not exclusively, the axes of the blowers are defined in the same PS plane. This plane PS is substantially parallel to the plane in which is defined the direction of wingspan E-E, ie the wing 1 of the aircraft. The blowers 12 are spaced from each other so as to allow the installation of the gas generator 11. The longitudinal axis X of the gas generator 11 may be included in the same plane PS as the axes of the blowers or be offset vertically relative to the plane of the axes of the blowers, which allows closer to the blowers 12 from one another. For this purpose, the gas generator 11 is housed in a housing 13 and the blowers 12 are each disposed in a fan casing 14. The casings 13, 14 are hooked directly to the frame of the wing 1 or via a pylon. The gas generator can be arranged behind the fan casings (see Figure 2) or at least partly between the fan casings (see Figures 3 and 4). The upper part of the housings 13, 14 is arranged substantially in the same plane. This configuration facilitates the attachment of the propulsion unit. In the present invention, the terms "upper" and "lower" are defined with respect to a vertical direction, the aircraft generally being positioned substantially horizontally. The blowers 12 are driven via a power transmission mechanism (not shown) coupled to the shaft of the gas generator or by a gas flow taken from the gas generator. The gas generator 11 comprises from upstream downstream at least one inlet opening 11 e, a compressor, a combustion chamber and a turbine. The casing 13 of the gas generator terminates downstream by a gas ejection nozzle. It can be single or multi stream, single or multi body as needed. The housing 13 of the gas generator has a generally cylindrical shape. The propulsion assembly 10 also comprises an air intake fairing 15 having a front wall 16 provided with an air inlet opening 17 which extends between the blowers 12. The front wall 16 is arranged between the blowers 12 and upstream of the gas generator 11, in a plane transverse to the axis of the gas generator. Moreover, the front wall 16 may have symmetry with respect to the plane PS of the fan shafts. The front wall 16 may also have a symmetry with respect to a median vertical plane passing between the two blowers 12. Specifically, the propulsion assembly 10 includes a nacelle 25 which includes the air intake fairing 15 formed upstream thereof. The nacelle 25 advantageously, but not exclusively, covers the upstream portions of the fan casings 13 as illustrated in FIGS. 2 to 4. In these examples, the nacelle 25 carries the upstream parts of the fan casings and the front wall. 16 is upstream of the gas generator. In FIGS. 5 and 6, the nacelle 25 forms an aerodynamic fairing containing or completely enveloping the blowers and the gas generator, as well as the air inlet opening 17. The air inlet opening 17 is configured to feed at least the gas generator 11. This air inlet opening 17 is disposed between the two blowers 12 and over the entire height of the end wall 16. In other words, the inlet opening air 17 extends on either side of the plane PS blowers containing the axes of rotation of the two blowers. Similarly, the air inlet opening 17 has a symmetry with respect to a vertical plane passing through the longitudinal axis of the gas generator. The air inlet opening is formed in a single part 17 as can be seen in FIGS. 1, 5 and 6. Alternatively and with reference to FIG. 7, the air intake opening is formed of two parts 17, 17 'distributed on either side of the plane PS of blowers and separated from each other by a wall 18. The axis X of the gas generator 11 passes inside the inlet opening 17 or one of the air inlet opening portions 17, 17 '. The air inlet opening 17 has a curved shape so as to fit at least partly in the shape of an interspersing zone which is delimited by air inlet lips 19 surrounding the air inlets of the housings blowers here of circular section. In particular, the air inlet opening 17 has concave portions inwardly facing each other at the location of the fan plane PS. This curved shape may be an hourglass shape or have rounded ends as in the example with reference to Figure 6. Of course, any other form to adapt to the inter-fan zone is conceivable. In FIGS. 2, 4 and 5, the air intake lips 19 of the remote blowers are defined in the same plane AB, which is here substantially perpendicular to the axis of the gas generator. The front wall 16 carrying the air inlet opening 17 is also defined in this plane AB. In Figures 3 and 6, the blowers are axially offset relative to each other so as to follow the arrow that the aircraft wing. In particular, the air intake lips 19 of the remote blowers 12 are defined in BC and CD planes axially offset with respect to one another and substantially parallel. In this example, the planes BC and CD of the lips 19 of air inlet are substantially parallel to each other and perpendicular to the axis of the gas generator. The front wall 16 is defined in the plane of the fan 12 which is located on the side of the free end of the wing. In other words, the air inlet opening 17 is situated substantially in the same plane CD as that defined by the air intake lip of the fan furthest downstream. With reference to FIG. 8, the propulsion assembly further comprises an air supply device configured to feed the gas generator 11 with a portion of the incoming air and to withdraw from the remaining part of the air entering a flow of cooling air for cooling elements of the propulsion assembly and / or a wing supporting the propulsion assembly. For this purpose, the air supply device comprises an air inlet sleeve 20 comprising an inlet duct 21 and a supply duct 22 of the gas generator 11 fed by the inlet duct 21. The latter is oriented along a first axis A1 substantially parallel and offset with respect to the longitudinal axis X of the gas generator. The supply duct 22 is connected to the inlet opening 11e of the gas generator 11 and is oriented along the X axis of the gas generator. The inlet duct 21 has an opening 21 disposed here below the plane PS of blowers. In other words, the inlet duct 21 and the supply duct 22 have an S-shaped axial section, the opening 21a of which is in fluid communication with the lower part of the inlet opening. air 17 and a downstream outlet is in fluid communication with the inlet opening 11e of the gas generator 11. The air supply device also comprises a ventilation duct 23 in fluid communication with the air inlet opening 17. This ventilation duct 23 is situated essentially above the plane PS of blowers. Thus, a part of the air entering the air inlet opening 17 is fed into the ventilation duct 23 from which fresh air is taken to cool elements of the propulsion assembly and is then rejected especially above the primary flow having passed through the gas generator 11. The exhaust air then forms a fluidic protective film to protect the intrados surface 3 of the wing 1 from the excessive heat of the exhaust gas. The other part of the air entering the air inlet opening 17 is fed into the inlet duct 21 as previously described. The ventilation duct 23 is delimited in part by a wall of the inlet duct 21, which wall separates the flow of air entering the ventilation duct 23 into ventilation flows passing along an outer casing of the gas generator. 11. Referring to Figure 7, in which the front wall 16 comprises two air inlet opening portions 17, 17 'separated from each other by a wall 18 constituted by a median portion of the front wall 16, the lower part air intake opening 17 feeds the air inlet sleeve 20, and the upper air inlet opening portion 17 'is configured to supply the ventilation duct 23. In this example, the upper part of the air inlet opening 17 'is located above the median wall 18, while the lower part of the air inlet opening 17 is located below this median wall 18 . Of course, in another configuration of the propulsion assembly not shown, the lower portion of the air inlet opening 17 may be in fluid communication with the ventilation duct, and the upper portion of the inlet opening air 17 'in fluid communication with the air inlet sleeve 20, in which case the gas generator 11 can be arranged substantially under the plane PS blowers of the propulsion assembly. It should be noted that in another embodiment not shown, an air intake sleeve and its supply duct supplying air to the gas generator may be arranged substantially on the same side of the plane of blowers as the generator of gas. A particle deflection device for preventing ingestion of particles by the gas generator may include one or more baffle elements in the path between the opening of the air inlet sleeve and the inlet opening of the gas generator. In this way, the particles whose incident trajectory is directed towards the inlet opening of the gas generator strike an inclined surface of a deflector element, to bounce and deviate their trajectory towards evacuation zones outside this entrance opening.
权利要求:
Claims (11) [1" id="c-fr-0001] A propulsion unit (10) for an aircraft, comprising a single gas generator (11) and two blowers (12) rotated by the gas generator (11) and deported on either side of a vertical plane passing through a longitudinal axis (X) of the gas generator, the axes of rotation of the fans extending substantially in the same plane (PS) of blowers, characterized in that it comprises a fairing (15) input of air formed upstream of a nacelle (25) connecting the blowers, said fairing (15) having between the blowers (12) an air inlet opening (17, 17 ') extending substantially perpendicularly in the plane (PS) of blowers and on either side of this plane, the propulsion assembly (10) further comprising an air supply device configured to feed the gas generator (11) with a part air entering and to withdraw from the remaining part of the incoming air a flow of Cooling air for cooling elements of the propulsion unit and / or a wing (1) supporting the propulsion unit. [2" id="c-fr-0002] 2. Assembly (10) according to claim 1, characterized in that the longitudinal axis (X) of the gas generator passes inside the air inlet opening (17,17 '). [3" id="c-fr-0003] 3. Assembly (10) according to any one of the preceding claims, characterized in that the blowers (12) have air inlet lips (19) defined in the same plane (AB). [4" id="c-fr-0004] 4. Assembly (10) according to any one of claims 1 and 2, characterized in that the blowers (12) have air inlet lips (19) defined in axially offset planes (BC, CD) and substantially parallel. [5" id="c-fr-0005] 5. Assembly (10) according to claim 4, characterized in that the air inlet opening (17) is situated substantially in the same plane as that defined by the lip (19) of the air intake of the blower the most downstream. [6" id="c-fr-0006] 6. Assembly (10) according to any one of the preceding claims, characterized in that the air inlet opening is formed in a single portion (17). [7" id="c-fr-0007] 7. Assembly (10) according to any one of claims 1 to 5, characterized in that the air inlet opening is formed of two parts (17, 17 ') distributed on either side of the plane blowers and separated from each other by a wall (18). [8" id="c-fr-0008] 8. Assembly (10) according to any one of the preceding claims, characterized in that the air inlet opening (17, 17 ') has a symmetry with respect to a vertical plane passing through the longitudinal axis ( X) of the gas generator. [9" id="c-fr-0009] 9. Assembly (10) according to any one of claims 2 to 8, characterized in that the longitudinal axis (X) of the gas generator is located above the plane (PS) of blowers, and the device of air supply comprises an air intake sleeve (20) supplying the gas generator (11), said air intake duct (20) comprising upstream an inlet duct (21) presenting an opening (21a) located substantially under the plane of blowers. [10" id="c-fr-0010] 10. Assembly (10) according to claim 9, characterized in that the air supply device comprises a ventilation duct (23) located substantially above the plane (PS) of blowers and which is taken from the flow of air. cooling air. [11" id="c-fr-0011] 11. Aircraft propellant wing (1), characterized in that it supports a propulsion assembly (10) according to any one of the preceding claims.
类似技术:
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同族专利:
公开号 | 公开日 US20170137135A1|2017-05-18| FR3043653B1|2018-11-09| US10518890B2|2019-12-31|
引用文献:
公开号 | 申请日 | 公开日 | 申请人 | 专利标题 DE1216117B|1961-03-09|1966-05-05|Hawker Siddeley Aviation Ltd|Airplane with swiveling axial fans on the wing| US3229933A|1964-06-05|1966-01-18|Gen Electric|Cruise fan powerplant| US20100011741A1|2007-06-05|2010-01-21|Michael Babu|Gas turbine engine with dual fans driven about a central core axis| US20090229243A1|2008-02-28|2009-09-17|Volker Guemmer|Aircraft propulsion unit in multi-fan design| US20140183296A1|2012-12-31|2014-07-03|United Technologies Corporation|Gas Turbine Engine Having Fan Rotor Driven by Turbine Exhaust and With a Bypass| FR3009028A1|2013-07-23|2015-01-30|Snecma|PROPULSIVE AIRCRAFT SYSTEM WITH AUXILIARY BLOWER DRAINED IN ROTATION BY GEAR AND METHOD FOR PROPULSION THEREOF| US3054577A|1961-02-27|1962-09-18|Forschungszentrums Der Luftfah|Power plant for jet propelled aircraft| US6792745B2|2002-08-09|2004-09-21|The Boeing Company|High bypass multi-fan engine| US7752834B2|2006-10-25|2010-07-13|United Technologies Corporation|Aircraft propulsion systems| US9297270B2|2012-02-29|2016-03-29|United Technologies Corporation|Gas turbine engine driving multiple fans| GB201320988D0|2013-11-28|2014-01-15|Rolls Royce Plc|An aircraft|FR3042010B1|2015-10-05|2018-07-13|Safran Aircraft Engines|AIRCRAFT WITH A MULTI-BLOWING PROPULSIVE ASSEMBLY FIXED UNDER AILE| FR3052743B1|2016-06-20|2018-07-06|Airbus Operations|AIRCRAFT ASSEMBLY COMPRISING PROPULSION ENGINES BY INGESTION OF THE LIMIT LAYER| US10507930B2|2016-11-22|2019-12-17|Rolls-Royce North American Technologies Inc.|Airplane with angled-mounted turboprop engine| US11111029B2|2017-07-28|2021-09-07|The Boeing Company|System and method for operating a boundary layer ingestion fan| US10759545B2|2018-06-19|2020-09-01|Raytheon Technologies Corporation|Hybrid electric aircraft system with distributed propulsion| US10906657B2|2018-06-19|2021-02-02|Raytheon Technologies Corporation|Aircraft system with distributed propulsion|
法律状态:
2016-11-03| PLFP| Fee payment|Year of fee payment: 2 | 2017-05-19| PLSC| Publication of the preliminary search report|Effective date: 20170519 | 2017-10-20| PLFP| Fee payment|Year of fee payment: 3 | 2018-09-14| CD| Change of name or company name|Owner name: SAFRAN AIRCRAFT ENGINES, FR Effective date: 20180809 | 2018-10-24| PLFP| Fee payment|Year of fee payment: 4 | 2019-10-22| PLFP| Fee payment|Year of fee payment: 5 | 2020-10-21| PLFP| Fee payment|Year of fee payment: 6 | 2021-10-20| PLFP| Fee payment|Year of fee payment: 7 |
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申请号 | 申请日 | 专利标题 FR1560904A|FR3043653B1|2015-11-13|2015-11-13|PROPELLER ASSEMBLY OF AN AIRCRAFT COMPRISING A GAS GENERATOR AND TWO BLOWERS DEPORTEES| FR1560904|2015-11-13|FR1560904A| FR3043653B1|2015-11-13|2015-11-13|PROPELLER ASSEMBLY OF AN AIRCRAFT COMPRISING A GAS GENERATOR AND TWO BLOWERS DEPORTEES| US15/346,612| US10518890B2|2015-11-13|2016-11-08|Propulsion assembly for an aircraft, comprising a gas generator and two offset fans| 相关专利
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