Have a deep view into what people are curious about.

🔗 Environment 🔗 Biology 🔗 Physics 🔗 Guild of Copy Editors 🔗 Energy 🔗 Chemical and Bio Engineering

Artificial photosynthesis is a chemical process that biomimics the natural process of photosynthesis to convert sunlight, water, and carbon dioxide into carbohydrates and oxygen. The term artificial photosynthesis is commonly used to refer to any scheme for capturing and storing the energy from sunlight in the chemical bonds of a fuel (a solar fuel). Photocatalytic water splitting converts water into hydrogen and oxygen and is a major research topic of artificial photosynthesis. Light-driven carbon dioxide reduction is another process studied that replicates natural carbon fixation.

Research of this topic includes the design and assembly of devices for the direct production of solar fuels, photoelectrochemistry and its application in fuel cells, and the engineering of enzymes and photoautotrophic microorganisms for microbial biofuel and biohydrogen production from sunlight.

🔗 Books 🔗 Alternative Views 🔗 Chemistry 🔗 Psychoactive and Recreational Drugs

PiHKAL: A Chemical Love Story is a book by Dr. Alexander Shulgin and Ann Shulgin, published in 1991. The subject of the work is psychoactive phenethylamine chemical derivatives, notably those that act as psychedelics and/or empathogen-entactogens. The main title, PiHKAL, is an acronym that stands for "Phenethylamines I Have Known and Loved".

The book is arranged into two parts, the first part being a fictionalized autobiography of the couple and the second part describing 179 different psychedelic compounds (most of which Shulgin discovered himself), including detailed synthesis instructions, bioassays, dosages, and other commentary.

The second part was made freely available by Shulgin on Erowid while the first part is available only in the printed text. While the reactions described are beyond the ability of people with a basic chemistry education, some tend to emphasize techniques that do not require difficult-to-obtain chemicals. Notable among these are the use of mercury-aluminum amalgam (an unusual but easy to obtain reagent) as a reducing agent and detailed suggestions on legal plant sources of important drug precursors such as safrole.

🔗 Companies 🔗 Korea 🔗 Food and drink 🔗 Korea/North Korea

Pyongyang (Chosongul: 평양관) is a restaurant chain named after the capital of North Korea, with around 130 locations worldwide. The restaurants are owned and operated by the Haedanghwa Group, an organization of the government of North Korea.

🔗 Maps 🔗 Photography

The Boston Camera, also known as Pie Face and officially classified as the K-42 Camera Model, was a prototype airborne photo reconnaissance camera manufactured for the United States Air Force by Boston University in 1951 and tested on the Convair B-36 and the C-97 Stratofreighter. The model carried on the first ERB-36D (44-92088) had a 6,096-millimetre (240.0 in) focal length, which was achieved using a series of lenses and mirrors. The lens had an f/8 stop and used a 1/400 second shutter speed, and could photograph a golf ball from an altitude of 45,000 feet (14,000 m) feet. The camera used 18-by-36-inch (46 by 91 cm) negatives. The camera was installed aboard Boeing C-97A 49-2592 (not an "RC-97" or "EC-97" as often widely quoted) which was used operationally by the 7405th Support Squadron based at Wiesbaden, West Germany between 1952 and 1962. It was given to the Air Force Museum in 1964, along with a contact print of a golf ball on a course.

In the words of CIA historian Dino Brugioni:

The lens was designed in 1947 by Dr. James Baker for installation in a camera designed by the Boston University Optical Research Laboratory. The camera weighed about three tons, and eight hundred pounds of lead shot were required to balance it. Supposedly, it was first installed and test-flown in an RB-36, then installed as a left-looking oblique camera in an RC-97. The first photo Arthur Lundahl and I saw from this project was of New York City. The aircraft was seventy-two miles away, and yet we could see people in Central Park.

The Boston Camera was plagued with problems that caused it to vibrate and produce smearing on the newspaper-sized negative, so that photo interpreters would see several smeared frames along with several clear ones. It is currently displayed at the National Museum of the US Air Force in Dayton, Ohio.

From the display placard:

This camera, manufactured for the US Air Force by Boston University in 1951, is the largest aerial camera ever built. It was installed in an RB-36D in 1954 and tested for about a year. Later it was used in a C-97 aircraft flying along the air corridor through communist East Germany to Berlin, but a 10,000 ft (3,000 m) altitude restriction imposed by the communists made the camera less useful than at a higher altitude. It was also used on reconnaissance missions along the borders of Eastern European nations. The camera made an 18 x 36 inch negative and was so powerful a photo interpreter could detect a golf ball from an altitude of 45,000 feet (14,000 m). Dr. James Baker of Harvard University designed the camera.

Technical Notes:

Shutter Speed: 1/400 sec

Weight: 6,500 lbs (3 metric ton) (camera and aircraft mount)

🔗 Mathematics

Ramanujan summation is a technique invented by the mathematician Srinivasa Ramanujan for assigning a value to divergent infinite series. Although the Ramanujan summation of a divergent series is not a sum in the traditional sense, it has properties which make it mathematically useful in the study of divergent infinite series, for which conventional summation is undefined.

🔗 United States 🔗 Biography 🔗 Biography/science and academia 🔗 Astronomy 🔗 United States/Arizona 🔗 Astronomy/Solar System

Robert Burnham Jr. (June 16, 1931 – March 20, 1993) was an American astronomer, best known for writing the classic three-volume Burnham's Celestial Handbook. He is the discoverer of numerous asteroids including the Mars crossing asteroid 3397 Leyla, as well as six comets.

Burnham's late years were tragic; he died destitute and alone. However, he is remembered by a generation of deep sky observers for his unique contribution to astronomy, the Celestial Handbook. The main-belt asteroid 3467 Bernheim was named in his honor.

🔗 Musical Instruments

The Siemens Synthesizer (or "Siemens Studio für Elektronische Musik") was developed in Germany in 1959 by the German electronics manufacturer Siemens, originally to compose live electronic music for its own promotional films.

From 1956 to 1967, it had a significant influence on the development of electronic music. Among others, Mauricio Kagel, Henri Pousseur, Herbert Brün and Ernst Krenek completed important electronic works there.

🔗 Military history 🔗 Military history/Fortifications 🔗 Military history/Cold War 🔗 Military history/Balkan military history 🔗 Albania 🔗 Military history/European military history

Concrete military bunkers are a ubiquitous sight in Albania, with an average of 5.7 bunkers for every square kilometer (14.7 per square mile). The bunkers (Albanian: bunkerët) were built during the Hoxhaist government led by the Leader Enver Hoxha from the 1960s to the 1980s, as the government fortified Albania by building more than 750,000 bunkers.

Hoxha's program of "bunkerization" (bunkerizimi) resulted in the construction of bunkers in every corner of the then-People's Socialist Republic of Albania, ranging from mountain passes to city streets. They were never used for their intended purpose during the years that Hoxha governed. The cost of constructing them was a drain on Albania's resources, diverting them away from dealing with the country's housing shortage and poor roads.

The bunkers were abandoned following the dissolution of the communist government in 1992. A few were used in the Insurrection of 1997 and the Kosovo War of 1999. Most are now derelict, though some have been reused for a variety of purposes, including residential accommodation, cafés, storehouses, and shelters for animals or the homeless.

🔗 Environment 🔗 Urban studies and planning 🔗 Chicago 🔗 Illinois

The Tunnel and Reservoir Plan (abbreviated TARP and more commonly known as the Deep Tunnel Project or the Chicago Deep Tunnel) is a large civil engineering project that aims to reduce flooding in the metropolitan Chicago area, and to reduce the harmful effects of flushing raw sewage into Lake Michigan by diverting storm water and sewage into temporary holding reservoirs. The megaproject is one of the largest civil engineering projects ever undertaken in terms of scope, cost and timeframe. Commissioned in the mid-1970s, the project is managed by the Metropolitan Water Reclamation District of Greater Chicago. Completion of the system is not anticipated until 2029, but substantial portions of the system have already opened and are currently operational. Across 30 years of construction, over $3 billion has been spent on the project.

🔗 Java

Java Card is a software technology that allows Java-based applications (applets) to be run securely on smart cards and more generally on similar secure small memory footprint deviceswhich are called “secure elements” (SE). Today, a Secure Element is not limited to its smart cards and other removable cryptographic tokens form factors; embedded SEs soldered onto a device board and new security designs embedded into general purpose chips are also widely used. Java Card addresses this hardware fragmentation and specificities while retaining code portability brought forward by Java.

Java Card is the tiniest of Java platforms targeted for embedded devices. Java Card gives the user the ability to program the devices and make them application specific. It is widely used in different markets: wireless telecommunications within SIM cards and embedded SIM, payment within banking cards and NFC mobile payment and for identity cards, healthcare cards, and passports. Several IoT products like gateways are also using Java Card based products to secure communications with a cloud service for instance.

The first Java Card was introduced in 1996 by Schlumberger's card division which later merged with Gemplus to form Gemalto. Java Card products are based on the specifications by Sun Microsystems (later a subsidiary of Oracle Corporation). Many Java card products also rely on the GlobalPlatform specifications for the secure management of applications on the card (download, installation, personalization, deletion).

The main design goals of the Java Card technology are portability, security and backward compatibility.