Nuclear magnetic resonance was first described and measured in molecular beams by Isidor Rabi in 1938. In 1944, Rabi was awarded the Nobel Prize in Physics for this work. In 1946, Felix Bloch and Edward Mills Purcell expanded the technique for use on liquids and solids. They shared the Nobel Prize in Physics in 1952 for this discovery.
Purcell had worked on the development of radar during World War II at the Massachusetts Institute of Technology's Radiation Laboratory. His work during that project on the production and detection of radio frequency power and on the absorption of such RF power by matter laid the background for Rabi's discovery of NMR.
Rabi, Bloch, and Purcell noticed that magnetic nuclei, like H and P, could absorb RF energy when placed in a magnetic field of a strength specific to the identity of the nuclei. When this absorption occurs, the nucleus is described as being "in resonance". Different atomic nuclei within a molecule resonate at different (radio) frequencies for the same magnetic field strength. The observation of such magnetic resonance frequencies of the nuclei present in a molecule allows any trained user to discover essential, chemical and structural information about the molecule.
After World War II, the development of NMR as a technique in analytical chemistry and biochemistry happened at the same time as the development of electromagnetic technology and advanced electronics and their introduction into civilian use. In the 1960s, William Lipscomb was a pioneer in using NMR to study chemical structures. He worked out how to look at NMR data to tell what atoms are connected together in a molecule. This is called chemical shift.
Herbert A. Hauptman
Herbert Aaron Hauptman (February 14, 1917 – October 23, 2011) was an American mathematician. He won a Nobel Prize. He made a mathematical method to find a molecular structures based on the X-ray patterns of crystallized materials. With Jerome Karle, he won the 1985 Nobel Prize in Chemistry.
He was born in New York City. He was the oldest child of Israel Hauptman and Leah Rosenfeld, and of Jewish descent.
Hauptman was interested in science and mathematics from an early age. He studied at Townsend Harris High School. He graduated from the City College of New York (1937). He earned an M.A. degree in mathematics from Columbia University in 1939. He married Edith Citrynell on November 10, 1940, and had two daughters.
After World War II, he began working together with Jerome Karle, a physical chemist, at the Naval Research Laboratory in Washington, D.C.. He also enrolled in the Ph.D. program at the University of Maryland, College Park. They used their mathematics and physical chemistry skills to solve the phase problem of X-ray crystallography. By 1955, he had received his Ph.D. in mathematics, and they had worked out the direct methods in X-ray crystallography. Their 1953 article, "Solution of the Phase Problem I. The Centrosymmetric Crystal", contained the main ideas, the most important of which was the introduction of probabilistic methods.
In 1970 he joined the Medical Foundation of Buffalo, becoming its Research Director in 1972. At this time he developed the neighborhood principle and extension concept. These theories were further developed during the following years.
Hauptman who was an atheist, signed with 21 other Nobel laureates the Humanist Manifesto in 2003.
Viking program
The Viking program was a NASA mission that sent two spacecraft to the planet Mars. These spacecraft were called Viking 1 and Viking 2. Each spacecraft was made of an orbiter and a lander. The orbiters took pictures of Mars from their orbit and sent information to Earth. The landers gathered scientific data on the surface of the planet.
Both Viking spacecraft were launched in 1975 and both reached Mars in 1976. Scientists chose landing places for both landers from the pictures that the orbiters had taken. Then the landers were released from the orbiters and they went down to their landing places. The orbiters continued to take pictures while the landers studied the surface of the planet and did other things. All of the spacecraft, including both orbiters and both landers, kept working for longer than they had been planned to. Eventually, they broke down. Viking 2 Orbiter stopped working in 1978, Viking 1 Orbiter and Viking 2 Lander in 1980, and Viking 1 Lander in 1982.
The Viking program was the most expensive and difficult mission ever sent to Mars. The program cost a total of US$1 billion. The program was very successful. Most of the knowledge about Mars until the late 1990s came from the Viking mission.
Piculet
The piculets are a subfamily of small woodpeckers which are mostly in tropical South America, with just three Asian and one African species.
Like true woodpeckers, piculets have large heads, long tongues to get their insect prey and zygodactyl feet, with two toes pointing forward, and two backwards. However, they lack the stiff tail feathers that woodpeckers use when climbing trees. They are more likely to perch on a branch rather than an upright trunk.
They eat insects and grubs mainly from decaying wood. They re-use woodpecker holes for nesting, rather than making their own holes. The eggs are white, as with many hole nesters.
There are 30 species in all. It is known that they split off from mainstream woodpeckers in the middle Miocene about 15 million years ago (mya). Splits between the three genera happened about 7.9 mya.
Typically these birds have grey or dull green upperparts and dark-streaked white underparts.
Fallin' for You
"Fallin' for You" is a song by the recording artist Colbie Caillat. The song was released June 29, 2009 as the lead single off her album "Breakthrough", which was also released in 2009. The lyrics speak of someone falling for a guy with whom they are friends.
Moulting
Moulting (or molting) is the manner in which an animal routinely casts off part of its body (usually the outer layer or covering) at particular times of year, or at specific points in its life cycle. Moulting is also known as sloughing, shedding, or for some species, ecdysis.
Moulting can involve the epidermis (skin), and hair, fur, wool, or other external layer. In some species, other body parts may be shed, for example, wings in some insects. Examples include old feathers in birds, old hairs in mammals (especially dogs and other canidae), old skin in reptiles, and the entire exoskeleton in arthropods.
In arthropods, such as insects, arachnids and crustaceans, moulting is the shedding of the exoskeleton (or shell).
This process of moulting is called ecdysis. It is the defining feature of a whole group of invertebrates, the clade Ecdysozoa. This group includes the arthropods, nematodes, velvet worms, horsehair worms, rotifers, tardigrades and Cephalorhyncha. Since the cuticles of these animals often forms an inelastic exoskeleton, it is shed during growth and a new, larger covering is formed. Amongst fossils, trilobites and eurypterida used ecdysis.
Ecdysis is part of the whole process of metamorphosis. The different stages (called 'instars') and the development of new 'apparatus' (such as sense organs) is necessary as the creature moves from one form to another. The new exoskeleton is initially soft but hardens after the moulting of the old exoskeleton.
Detention (imprisonment)
Detention is a depriving of liberty of a person by the authority of a government or a country, usually the police. Such depriving liberty is allowed only in the case that the person can considered to have committed a crime. Other depriving liberty is called arbitrary detention and prohibited by article 9 of the Universal Declaration of Human Rights and International Covenant on Civil and Political Rights. And even detention is done legally, the person must be treated with humanity and respected the person's dignity according to the Convention against Torture.
Charles III of Spain