omniomni/omni-engineering huggingface dataset:
Douglas Cloudster II. The Douglas Cloudster II was an American prototype five-seat light aircraft of the late 1940s. It was of unusual layout, with two buried piston engines driving a single pusher propeller. Only a single example was built, which flew only twice, as it proved too expensive to be commercially viable.

Design and development

During the early 1940s, Douglas Aircraft Company developed a configuration for high-performance twin-engined aircraft, in which the engines were buried in the fuselage, driving propellers mounted behind a conventional tailplane, in order to reduce drag by eliminating drag inducing objects such as engines from the wing.  This layout was first demonstrated in the Douglas XB-42 Mixmaster bomber, which first flew in 1944, showing a 30% reduction in drag compared with a conventional twin-engined layout, while eliminating handling problems due to asymmetric thrust when flying on one engine.

Owing to the initial success of the XB-42, Douglas adopted this promising new layout for a medium-range airliner, the DC-8 and a five-seat light aircraft suitable for executive or air charter use, the Model 1015 or Cloudster II.

The Cloudster II was a low-winged monoplane with a retractable nosewheel undercarriage. The pilot and four passengers sat in an enclosed cabin well ahead of the unswept, laminar flow wing. Two air-cooled piston engines were buried in the rear fuselage, driving a single eight foot diameter twin-bladed propeller, mounted behind the empennage via driveshafts taken from P-39 fighters. Two air intakes forward of the wing directed cooling air to the engines, which then exhausted beneath the fuselage.

Operational history
The Cloudster II made its maiden flight on March 12, 1947. Although the aircraft's performance and handling were good, it suffered from excessive vibration, and overheated when it was on the ground. Further development was abandoned late in 1947, with the prototype having flown only twice, as the post-war civil flying market had not developed as hoped, while the selling price had risen from an originally planned $30,000 to $68,000, rendering the aircraft commercially unviable.

Specifications

See also

References

Notes

Citations

Bibliography

 Francillon, René J. McDonnell Douglas Aircraft since 1920. London: Putnam, 1979. .

External links

 "5 Passenger Pusher", Popular Science, 1947, p. 35
 Photos - Aerofiles

Abandoned civil aircraft projects of the United States
Cloudster II
1940s United States civil utility aircraft
Twin-engined single-prop pusher aircraft
Low-wing aircraft
Aircraft first flown in 1947
MILMEGA. MILMEGA is a company specializing in designing and manufacturing high-power amplifiers for electromagnetic compatibility (EMC) testing. Headquartered in Ryde on the Isle of Wight in England, MILMEGA mainly provides broadband amplifier products with frequency ranges from  to , with power levels from .

History 

Founded in 1987 by Dr John Yelland, MILMEGA's first design was a contract to deliver a narrow-band amplifier to meet the requirements of a medical product used in the treatment of prostate cancer.

MILMEGA went onto design and manufacture high-power amplifiers for commercial and government applications.

Milmega was first sold in 1997 to an American company.

In 2004, the company was acquired by its management team in a management buyout (MBO) in part financed by venture capital funding from South East Growth Fund.

Since the MBO the company has invested in the field of wide bandgap transistor technologies, specifically, silicon carbide transistor (SiC) and gallium nitride transistor (GaN) technologies.

In 2010, the company centralized its operations at the current factory at Ryde, on the Isle of Wight, and in the same year, launched its Chinese language website.

In February 2012, MILMEGA was purchased by Teseq Holding AG.

In April 2012, MILMEGA received the Queen's Awards for Enterprise for their 80 MHz to 1 GHz range of amplifier.

In January 2014, the Teseq Group was purchased by AMETEK Inc.

Today, MILMEGA's workforce consists of 35 design and production staff.

References 

Companies based on the Isle of Wight
Electrical engineering companies of the United Kingdom
List of educational institutions in Kakinada. Kakinada, the headquarters of Kakinada district in Andhra Pradesh, is a major educational hub, catering to the growing educational needs of the state. Over the past three decades, the city has seen significant growth in the number of residential colleges offering quality secondary education. Kakinada is home to several professional institutions, providing courses in engineering, medicine, information technology, law, and management at both graduate and postgraduate levels.

Jawaharlal Nehru Technological University (JNTU), Kakinada, offers engineering and business programs, while Rangaraya Medical College is regarded as one of the top medical institutions in the state. Additionally, the Andhra University Postgraduate Centre, established in 1977, provides higher education and is situated on a  campus in Thimmapuram, near Kakinada.

Medical College 

 Rangaraya Medical College

Engineering Colleges 
 Aditya Engineering College
 Kakinada Institute of Engineering and Technology

General Colleges 
 P. R. Government College
 Aditya Degree College

Private Unaided Co-Education Colleges 
 Ideal College of Arts and Sciences

University 
 Jawaharlal Nehru Technological University

Schools 
There are more than 600 schools in Kakinada. Some of the important schools are:

 Ashram Public School
 Akshara School

References 

 
Kakinada
Andhra Pradesh-related lists
Wright-Bellanca WB-1. The Wright-Bellanca WB-1 was designed by Giuseppe Mario Bellanca for the Wright Aeronautical corporation for use in record-breaking flights.

Development
The WB-1 was a high-winged monoplane with conventional landing gear and all-wood construction. The landing gear fairings were constructed to extend into wheel pants.

Operational history
The WB-1 was demonstrated at the 1925 Pulitzer Prize Air Races in New York. In the first day's flights, the WB-1 clocked in 121.8 mph in a closed course race. On day two, the WB-1 won, in a payload versus hp and speed efficiency contest, beating a Curtiss Oriole and Sikorsky S-31. In 1926, pilot Fred Becker crashed the overloaded aircraft in a world-record endurance attempt. The aircraft cartwheeled and broke up on a landing attempt.

Specifications (WB-1)

See also

References

External links
San Diego Air & Space Museum Archives

Wright aircraft
Karl-Heinz Streibich. Karl-Heinz Streibich (born 1952) is a German manager who served as chairman of the executive board and chief executive officer of the Germany-based software company Software AG from 2003 until 2018. Prior to that he was deputy chairman and deputy chief executive officer of T-Systems

Early life and education
Streibich was born in Germany. He holds a degree in communications engineering from the Offenburg University, Germany.

Career
Streibich started his career in 1981 at Dow Chemical Company in Rheinmünster, Germany, as a software development engineer. Three years later he joined ITT Industries as product marketing manager then moved to ITT-SEL AG now Alcatel-Lucent as managing director of the PC business. He joined Daimler Benz AG in 1989, where he served several IT-related executive positions before serving as deputy chairman and deputy chief executive officer of Debis Systemhaus facilitating the merger with T-Systems between 2000 and 2002. He is a member of the supervisory board (Aufsichtsrat) at Deutsche Messe AG, and holds several honorary positions, including member of the presidency of the German IT Association BITKOM, co-chairman of the platform “Digital administration and public IT“ within the framework of the German Chancellor's IT summit, and he is a co-founder of the German Software Cluster of Excellence.

From 2003 until 2018 Streibich served as chairman of the executive board and chief executive officer of the Germany-based software company Software AG. In this capacity, he was also responsible for the company's corporate marketing, audit, processes & quality, legal affairs, and corporate communications. Under his leadership, Software AG acquired webMethods for $546 million in cash to add networking software to its product line.

Streibich is the author of the book entitled The Digital Enterprise, published in 2014.

Other activities

Corporate boards 
 Software AG, Member of the Supervisory Board (since 2020)
 Munich Re, Member of the Supervisory Board (since 2019)
 Siemens Healthineers, Member of the Supervisory Board (since 2018)
 Deutsche Telekom, Member of the Supervisory Board (since 2013)
 Dürr AG, Member of the Supervisory Board (2011-2020), Chairman of the Supervisory Board (2018-2020)
 Wittenstein, Member of the Supervisory Board (2017-2019)
 Deutsche Messe, Member of the Supervisory Board (2013-2017)

Non-profit organizations 
 German Cancer Research Center (DKFZ), Member of the Advisory Council
 Senckenberg Nature Research Society, Member of the Board of Trustees

References

1952 births
Living people
Businesspeople from Hesse
Software AG
Enzmann starship. The Enzmann starship is a concept for a crewed interstellar spacecraft proposed in 1964 by Dr. Robert Enzmann. A three million ton ball of frozen deuterium would fuel nuclear fusion rocket engines contained in a cylindrical section behind that ball with the crew quarters. The craft would be about  long overall.

Design 
The ball of frozen deuterium would fuel thermonuclear-powered pulse propulsion units, similar to Project Orion engines. The spacecraft would be assembled in Earth orbit as part of a larger project preceded by interstellar probes and telescopic observation of target star systems. The rest of the spacecraft would be attached behind the ball as a seamless metallic fuel tank. The proposed method of tank construction would be to expand a plastic balloon in space and coat it with metal.

The spacecraft would be modular, and the main living area would be three identical  wide and long cylindrical modules. The Enzmann could function as an interstellar ark, supporting a crew of 200 but with space for expansion.

The Enzmann starship was detailed in the October 1973 issue of Analog, with a cover by space artist Rick Sternbach. The spacecraft described in that issue had some differences compared to the 1960s proposal, such as using a 12,000,000 ton (11,000,000 tonnes) ball of frozen deuterium. Enzmanns have been depicted by many space artists including Don Dixon, David A. Hardy, Syd Mead, Bob Eggleton, and Rick Sternbach.

Sources conflict about the projected speed, perhaps 30% of the speed of light, c, but 9% may be more likely. At 30%, relativistic effects between people on Earth and on the spacecraft, such as time dilation would become more noticeable, such as the shipboard time being less than the Earth observed time.

Overall specifications have varied somewhat, but the design has nuclear pulse engines at the rear, then cylinders for human habitation, then closer the front a large ball of fuel. Early versions were said to have 8 engines and later 24 nuclear rocket engines, which would be powered by the fusing of deuterium into helium-3.  A common feature was that the crew area was replicated 3 times for redundancy, and a common core pillar ran the length of the spacecraft and through the center of each habitation unit.

Further reading 

 G. Harry Stine article in Analog Science Fact & Science Fiction in 1973
 The design featured in cover art for this issue 

 "The Enzman Starship" JBIS

Astronomy Magazine “Slow Boat to Centauri” (1977)

See also
Interstellar travel
Balloon satellite
Project Daedalus

References

External links

The Enzmann Starship: History & Engineering Appraisal
Interstellar travel
1964 in science
Anigre. Anigre is an African hardwood commonly used for plywood, interior furniture, cabinetry, and high-end millwork applications. It is frequently sliced and sold as veneer, although it is available in board form as well. In board form it is used for boat building, general carpentry, and other light construction uses.

Characteristics
It is considered a tropical hardwood with a clear, cylindrical bole to . It can grow to heights of  with typical trunk diameters ranging from . Anigre has a medium texture with closed pores similar to maple. Growth rings aren't always well-defined, and the wood can be rather plain-looking; though certain figure is occasionally present, such as curly or mottled grain. The sapwood and the heartwood are not usually distinguishable.  The heartwood is a light yellowish-brown, sometimes with a pinkish hue. Color tends to darken with age. The quarter figured veneer has become a popular choice for furniture, cabinetry, and decorative architectural applications. It is said to have a faint odor similar to Cedar. In its untreated form Anigre is susceptible to termite and fungi attacks and generally has low durability. Anigre is usually considered easy to work with hand and power tools, although depending on the origin of the wood it can have a high silica content which can dull wood working tools quickly.

Origins
Anigre is often found in tropical East and West Africa, primarily in Cameroon but also in Angola, Congo, Ethiopia, Ghana, Guinea Bissau, Ivory Coast, Kenya, Nigeria, Sierra Leone, Uganda and Zaire. Exportation from Cameroon is prohibited by local laws.

Common names
Anigre, Aningre, Anegre, Aniegre, Aniegré, Aningré, Aningeria, Aninguerie, Mugangu, Muna, Osan, Anegre Blanc, Longhi, Mukaly, Tanganyika Nuss. Common pronunciations vary from Ah-Nee-Grey, Ah-Nee-Gra, Anna-Gra, Anna-Grey, Uh-Nee-Grey.

Scientific names
Anigre hardwood comes from several species in the family Sapotaceae, including Aningeria altissima,  Aningeria pierrei (synonym Aningeria robusta), Aningeria superba, and Gambeya gigantea (synonym Gambeyobotrys gigantea).

References

Wood
Chrysophylloideae
Plant common names
Naval Aircraft Factory TDN. The Naval Aircraft Factory TDN was an early unmanned combat aerial vehicle - referred to at the time as an "assault drone" - developed by the United States Navy's Naval Aircraft Factory during the Second World War. Developed and tested during 1942 and 1943, the design proved moderately successful, but development of improved drones saw the TDN-1 relegated to second-line duties, and none were used in operational service.

Design and development
The development of the radar altimeter and television in the early 1940s made remotely guided bomb- or torpedo-carrying aircraft a practical proposition. In January 1942, the Naval Aircraft Factory was instructed to initiate the development of such an aircraft, with a go-ahead for prototype construction being given in February. A production contract for 100 aircraft was issued in March, with John S. Kean being assigned as TDN-1 project manager, with the aircraft being designed to be capable of using either television or radar guidance. Constructed mainly from wood, the TDN-1 had a fixed tricycle landing gear, and could be fitted with a conventional cockpit in place of its guidance equipment for test flights.

In an example of the use of companies traditionally uninvolved in the aviation industry to reduce interference with higher priority projects, production of the final thirty aircraft was licensed to the Brunswick-Balke-Collender Company, a Michigan-based manufacturer of bowling balls and billiard tables.

Operational history
One hundred production TDN-1 aircraft were ordered in March 1942. Despite being specifically designed to be a simple, low-performance aircraft, and despite proving promising in testing, the type was considered to be too complicated and expensive for use operationally. The improved Interstate TDR was selected for development as an alternative, the majority of TDN-1s being used in the test, liaison and training roles, with some being expended as aerial targets. The TDN-1 is often credited as the first US drone to take off from an aircraft carrier freely (USS Sable). An Airspeed Queen Wasp had already been catapulted from HMS Pegasus in 1937.

Variants and operators
 United States Navy
XTDN-1
Four prototype aircraft powered by Franklin O-300 engines.
TDN-1
Production version of XTDN-1; 100 aircraft produced.

Specifications (TDN-1)

See also

References

Citations

Bibliography

 

 

 
 

Further reading

 

TDR
1940s United States bomber aircraft
Unmanned aerial vehicles of the United States
World War II guided missiles of the United States
High-wing aircraft
Aircraft first flown in 1942
Twin piston-engined tractor aircraft
Aircraft with fixed tricycle landing gear
François Frenkiel. François Naftali Frenkiel (Warsaw, 19 September 1910 – Rockville, Maryland, 9 July 1986) was a physicist and one of the founders of the American Institute of Physics (AIP) journal Physics of Fluids in 1958. He was the editor of Physics of Fluids from its establishment until 1981.

François Frenkiel, received his undergraduate education in Mechanical and Aeronautical Engineering at the University of Ghent, Belgium, and his Ph.D. in physics from the University of Lille in France where he studied under the direction of Kampé de Fériet. He immigrated to the US in 1947 and was associated successively with Cornell University, the U.S. Naval Ordnance Laboratory, the Johns Hopkins University Applied Physics Laboratory and, from 1960 until his retirement, with the David W. Taylor Naval Ship Research and Development Center.

In addition to being the founder and longtime editor of Physics of Fluids, he served on a large number of national and international committees, e.g., to name but a few, the International Union of Theoretical and Applied Mechanics (IUTAM), the U.S. National Committee on Theoretical and Applied Mechanics, and the Division of Fluid Dynamics of the American Physical Society of which he was the chairman and secretary on numerous occasions.

He published extensively in the field of turbulent flows and pioneered the application of high-speed digital computing methods to the measurement of turbulence and the mathematical modeling of urban pollution. He was elected Fellow of the American Physical Society, the American Geophysical Union, and the American Association for the Advancement of Science. Frenkiel retired in 1981 and died on 9 July 1986, in Washington, D.C.

The American Physical Society has named an award in his honor.

Notes

References
 

1910 births
1986 deaths
Fluid dynamicists
Fellows of the American Geophysical Union
Fellows of the American Physical Society
Vietnam Academy of Science and Technology. The Vietnam Academy of Science and Technology (VAST; ) is the largest and most prominent research institute in Vietnam. It was founded on 20 May 1975 as the Vietnam Academy of Science, then subsequently assumed its current name in 2008. Its infrastructure spans Hanoi, Ho Chi Minh City, Hải Phòng, Nha Trang, Đà Lạt, and Huế.

In March 2010, the VAST launched a peer-reviewed open access journal, Advances in Natural Sciences: Nanoscience and Nanotechnology (ANSN). The journal is jointly published with IOP Publishing.

The Vietnam National Satellite Center, renamed the Vietnam National Space Center (VNSC) in July 2017, was founded as a VAST research center on 16 September 2011 to implement space and satellite projects for the government of Vietnam.

Notes

External links
 Vietnam Academy of Science and Technology
 Advances in Natural Sciences: Nanoscience and Nanotechnology

Educational institutions established in 1975
Science and technology in Vietnam
Scientific organizations based in Vietnam
Technical universities and colleges in Vietnam
1975 establishments in Vietnam
Barton decarboxylation. The Barton decarboxylation is a radical reaction in which a carboxylic acid is  converted to a thiohydroxamate ester (commonly referred to as a Barton ester). The product is then heated in the presence of a radical initiator and a suitable hydrogen donor to afford the decarboxylated product. This is an example of a reductive decarboxylation. Using this reaction it is possible to remove carboxylic acid moieties from alkyl groups and replace them with other functional groups. (See Scheme 1) This reaction is named after its developer, the British chemist and Nobel laureate Sir Derek Barton (1918–1998).

Mechanism 
The reaction is initiated by homolytic cleavage of a radical initiator, in this case 2,2'-azobisisobutyronitrile (AIBN), upon heating. A hydrogen is then abstracted from the hydrogen source (tributylstannane in this case) to leave a tributylstannyl radical that attacks the sulfur atom of the thiohydroxamate ester. The N-O bond of the thiohydroxamate ester undergoes homolysis to form a carboxyl radical which then undergoes decarboxylation and carbon dioxide (CO2) is lost. The remaining alkyl radical (R·) then abstracts a hydrogen atom from remaining tributylstannane to form the reduced alkane (RH). (See Scheme 2) The tributyltin radical enters into another cycle of the reaction until all thiohydroxamate ester is consumed.

N-O bond cleavage of the Barton ester can also occur spontaneously upon heating or by irradiation with light to initiate the reaction. In this case a radical initiator is not required but a hydrogen-atom (H-atom) donor is still necessary to form the reduced alkane (RH). Alternative H-atom donors to tributylstannane include tertiary thiols and organosilanes. The relative expense, smell, and toxicity associated with tin, thiol or silane reagents can be avoided by carrying the reaction out using chloroform as both solvent and H-atom donor.

It is also possible to functionalize the alkyl radical by use of other radical trapping species (X-Y + R· -> R-X + Y·). The reaction proceeds due to the formation of the stable S-Sn bond and increasing aromaticity of the thiohydroxamate ester. There is also an overall increase in entropy due to the formation of gas which drives the reaction forward.

See also
 Barton–McCombie deoxygenation
 Hunsdiecker reaction
 Kochi reaction
 Krapcho decarboxylation
 Kolbe electrolysis

References

External links 
 Barton decarboxylation at organic-chemistry.org 
 Barton decarboxylation at themerckindex.cambridgesoft.com 

Organic reactions
Name reactions