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Lunar Orbiter program

The Lunar Orbiter program was a series of five unmanned lunar orbiter missions launched by the United States from 1966 through 1967. Intended to help select Apollo landing sites by mapping the Moon's surface, they provided the first photographs from lunar orbit and photographed both the Moon and Earth. All five missions were successful, 99 percent of the lunar surface was mapped from photographs taken with a resolution of 60 meters or better; the first three missions were dedicated to imaging 20 potential manned lunar landing sites, selected based on Earth-based observations. These were flown at low-inclination orbits; the fourth and fifth missions were devoted to broader scientific objectives and were flown in high-altitude polar orbits. Lunar Orbiter 4 photographed the entire nearside and nine percent of the far side, Lunar Orbiter 5 completed the far side coverage and acquired medium and high resolution images of 36 preselected areas. All of the Lunar Orbiter spacecraft were launched by Atlas-Agena-D launch vehicles.

The Lunar Orbiters had an ingenious imaging system, which consisted of a dual-lens camera, a film processing unit, a readout scanner, a film handling apparatus. Both lenses, a 610 mm narrow angle high resolution lens and an 80 mm wide angle medium resolution lens, placed their frame exposures on a single roll of 70 mm film; the axes of the two cameras were coincident so the area imaged in the HR frames were centered within the MR frame areas. The film was moved during exposure to compensate for the spacecraft velocity, estimated by an electro-optical sensor; the film was processed and the images transmitted back to Earth. During the Lunar Orbiter missions, the first pictures of Earth as a whole were taken, beginning with Earth-rise over the lunar surface by Lunar Orbiter 1 in August, 1966; the first full picture of the whole Earth was taken by Lunar Orbiter 5 on 8 August 1967. A second photo of the whole Earth was taken by Lunar Orbiter 5 on 10 November 1967; the Boeing-Eastman Kodak proposal was announced by NASA on 20 December 1963.

The main bus of the Lunar Orbiter had the general shape of a truncated cone, 1.65 m tall and 1.5 m in diameter at the base. The spacecraft was composed of three decks supported by an arch; the equipment deck at the base of the craft held the battery, flight programmer, inertial reference unit, Canopus star tracker, command decoder, multiplex encoder, traveling-wave tube amplifier, the photographic system. Four solar panels were mounted to extend out from this deck with a total span across of 3.72 m. Extending out from the base of the spacecraft were a high gain antenna on a 1.32 m boom and a low-gain antenna on a 2.08 m boom. Above the equipment deck, the middle deck held the velocity control engine, propellant and pressurization tanks, Sun sensors, micrometeoroid detectors; the third deck consisted of a heat shield to protect the spacecraft from the firing of the velocity control engine. The nozzle of the engine protruded through the center of the shield. Mounted on the perimeter of the top deck were four attitude control thrusters.

Power of 375 W was provided by the four solar arrays containing 10,856 n/p solar cells which would directly run the spacecraft and charge the 12 A·h nickel-cadmium battery. The batteries were used during the brief periods of occultation. Propulsion for major maneuvers was provided by the gimballed velocity control engine, a hypergolic 100 pound-force thrust Marquardt Corp. rocket motor. Three axis stabilization and attitude control were provided by four one lb-force nitrogen gas jets. Navigational knowledge was provided by five sun sensors, the Canopus star sensor, the inertial navigation system. Communications were via a 10 W transmitter and the directional one meter diameter high-gain antenna for transmission of photographs, a 0.5 W transmitter and omnidirectional low-gain antenna for other communications. Both transmitters operated in the S band at about 2295 MHz. Thermal control was maintained by a multilayer aluminized Mylar and Dacron thermal blanket which enshrouded the main bus, special paint and small heaters.

The photographic system was provided by Eastman Kodak and it was derived from a system, provided by the National Reconnaissance Office, designed for the U-2 and SR-71 reconnaissance planes. The camera used two lenses to expose a wide-angle and a high-resolution image on the same film; the wide-angle, medium resolution mode used an 80 mm F 2.8 Xenotar lens manufactured by Schneider Kreuznach of West Germany. The high-resolution mode used a 610 mm F 5.6 Panoramic lens manufactured by the Pacific Optical Company. The photographic film was developed in-orbit with a semidry process, it was scanned by a photomultiplier for transmission to Earth; this system was adapted under permission of the NRO from the SAMOS E-1 reconnaissance camera, built by Kodak for a short-lived USAF near-realtime satellite imaging project. The Air Force had offered NASA several spare cameras from the KH-7 GAMBIT program, but authorities became concerned over security surrounding the classified cameras, including the possibility of images of the Moon giving away their resolution.

Some proposals were made that NASA not publish the orbital parameters of the Lunar Orbiter probes so that the resolution of the images could not be calculated through their altitude. In the end, NASA's existing camera systems, while lower resolution, proved to be adequate for the needs of the mission; as a backup for Lunar Orbiter program, NASA and the NRO cooperated on the Lunar Mapping and Survey System

Vortex (Star Trek: Deep Space Nine)

"Vortex" is the 12th episode of the third season of the American science fiction television series Star Trek: Deep Space Nine. A visitor from the Gamma Quadrant, whom Odo arrests for murder and must extradite, claims he has met a Changeling before. During a business transaction between unscrupulous bar operator Quark and a pair of Miradorn twins, a visitor from the Gamma Quadrant, attempts to steal a valuable item. Odo intercedes, but not before one of the twins is killed. Odo takes Croden into custody, while Ah-kel, vows vengeance. Croden makes several comments to Odo regarding Changelings; this piques Odo's interest. Croden claims there were once shape-shifters on his homeworld, who were persecuted and driven off the planet, he claims to know of a place where they still exist, tried to tempt Odo by offering to bring him to this colony. Odo is dubious of Croden's stories until Croden shows him a necklace with a stone that changes shape. Dr. Bashir examines it and tells Odo that, given its composition, it could be distantly related to Odo.

Croden's homeworld demands his return, Commander Sisko sends Odo to return him. Ah-Kel intimidates Quark into revealing that Odo has taken Croden to the Gamma Quadrant, he pursues them to exact vengeance on Croden. In the runabout shuttle, Croden tells Odo that he was a political prisoner on his home planet, most of his family was killed by the government; when Ah-Kel appears in pursuit, Odo is forced to release Croden to assist in evading Ah-Kel's ship. Croden navigates the Chamra Vortex, an asteroid field filled with unstable pockets called toh-maire, lands on a planet he claims contains the Changeling colony. On the surface, Croden's eagerness reignites Odo's doubt. Odo demands the truth of Croden's stories. Croden reveals that he has never met a Changeling. Croden uses the stone to open a chamber he had left on the planet's surface, containing his daughter, whom he had put into stasis. Ah-Kel fires on the planet. A falling rock incapacitates Croden carries him back to the ship. In the Vortex, Odo tricks Ah-Kel into firing on a pocket of toh-maire.

Croden decides to answer for his crime on his homeworld and asks Odo to care for his daughter. Croden gives Odo his necklace containing the Changeling stone as a sign of thanks. In 2015, Geek.com recommended this episode as "essential watching" for their abbreviated Star Trek: Deep Space Nine binge-watching guide. P. Farrand, Nitpicker's Guide for Deep space Nine Trekkers New York: Dell: 52 - 55 Vortex on IMDb "Vortex" at TV.com Vortex at Memory Alpha Vortex at StarTrek.com

Hammett equation

The Hammett equation in organic chemistry describes a linear free-energy relationship relating reaction rates and equilibrium constants for many reactions involving benzoic acid derivatives with meta- and para-substituents to each other with just two parameters: a substituent constant and a reaction constant. This equation was developed and published by Louis Plack Hammett in 1937 as a follow-up to qualitative observations in a 1935 publication; the basic idea is that for any two reactions with two aromatic reactants only differing in the type of substituent, the change in free energy of activation is proportional to the change in Gibbs free energy. This notion does not follow from elemental thermochemistry or chemical kinetics and was introduced by Hammett intuitively; the basic equation is: log ⁡ K K 0 = σ ρ relating the equilibrium constant, K, for a given equilibrium reaction with substituent R and the reference K0 constant when R is a hydrogen atom to the substituent constant σ which depends only on the specific substituent R and the reaction constant ρ which depends only on the type of reaction but not on the substituent used.

The equation holds for reaction rates k of a series of reactions with substituted benzene derivatives: log ⁡ k k 0 = σ ρ. In this equation k0 is the reference reaction rate of the unsubstituted reactant, k that of a substituted reactant. A plot of log for a given equilibrium versus log for a given reaction rate with many differently substituted reactants will give a straight line; the starting point for the collection of the substituent constants is a chemical equilibrium for which both the substituent constant and the reaction constant are arbitrarily set to 1: the ionization of benzoic acid or benzene carboxylic acid in water at 25 °C. Having obtained a value for K0, a series of equilibrium constants are now determined based on the same process, but now with variation of the para substituent—for instance, p-hydroxybenzoic acid or p-aminobenzoic acid; these values, combined in the Hammett equation with K0 and remembering that ρ = 1, give the para substituent constants compiled in table 1 for amine, ethoxy, methyl, bromine, iodine and cyano substituents.

Repeating the process with meta-substituents afford the meta substituent constants. This treatment does not include ortho-substituents; the σ values displayed in the Table above reveal certain substituent effects. With ρ = 1, the group of substituents with increasing positive values—notably cyano and nitro—cause the equilibrium constant to increase compared to the hydrogen reference, meaning that the acidity of the carboxylic acid has increased; these substituents stabilize the negative charge on the carboxylate oxygen atom by an electron-withdrawing inductive effect and by a negative mesomeric effect. The next set of substituents are the halogens, for which the substituent effect is still positive but much more modest; the reason for this is that while the inductive effect is still negative, the mesomeric effect is positive, causing partial cancellation. The data show that for these substituents, the meta effect is much larger than the para effect, due to the fact that the mesomeric effect is reduced in a meta substituent.

With meta substituents a carbon atom bearing the negative charge is further away from the carboxylic acid group. This effect is depicted in scheme 3, where, in a para substituted arene 1a, one resonance structure 1b is a quinoid with positive charge on the X substituent, releasing electrons and thus destabilizing the Y substituent; this destabilizing effect is not possible. Other substituents, like methoxy and ethoxy, can have opposite signs for the substituent constant as a result of opposing inductive and mesomeric effect. Only alkyl and aryl substituents like methyl are electron-releasing in both respects. Of course, when the sign for the reaction constant is negative, only substituents with a negative substituent constant will increase equilibrium constants; because the carbonyl group is unable to serve a source of electrons for -M groups, for reactions involving phenol and aniline starting materials, the σp values for electron-withdrawing groups will appear too small. For reactions where resonance effects are expected to have a major impact, a modified parameter, a modified set of σp– constants may give a better fit.

This parameter is defined using the ionization constants of para substituted phenols, via a scaling factor to match up the values of σp– with those of σp for "non-anomalous" substituents, so as to maintain comparable ρ values: for ArOH ⇄ ArO– + H+, we define σ p − = 1 2.11 log 10 ⁡. The carbonyl carbon of a benzoic acid is at a nodal position and unable to serve as a sink for +M groups, thus for reactions involving carbocations at the α-position, the σp values for electron-donating groups will appear insufficiently negative. Based on similar considerations, a set of σp+ constants give better fit for

Great Flinders Football League

The Great Flinders Football League is an Australian rules football competition based in the Eyre Peninsula region of South Australia, Australia. It is an affiliated member of the South Australian National Football League. In 2006 Ramblers Football Club were premiers; the Great Flinders Football League began in 1911 with founding clubs including Cummins, Cummins Ramblers, Mount Hope, Rovers and Yallunda Flat. List of recent premiers of GFFL. Country footy Encyclopedia of South Australian country football clubs / compiled by Peter Lines. ISBN 9780980447293 South Australian country football digest / by Peter Lines ISBN 9780987159199

Tumbok

Tumbok is a 2011 Filipino horror film starring Cristine Reyes and Carlo Aquino produced by Viva Films. A married couple inherits a condo unit, unknown to them the area resides in a negative energy convergence area, which made the inhabitants unlucky. Cristine Reyes as Grace Carlo Aquino as Ronnie Ryan Eigenmann as Mark Ara Mina as Rita Jao Mapa as Benjie DJ Durano as Ward LJ Moreno as Lumen Wendy Valdez as Lizet Malou de Guzman as Elsie Ana Capri as Idang Abby Bautista as Isay Dino Imperial as Gio Francheska Salcedo as Yumi Box Office: 10.53 million List of ghost films Official website Tumbok on IMDb

Buccal nerve

The buccal nerve is a nerve in the face. It is a branch of the mandibular nerve and transmits sensory information from skin over the buccal membrane and from the second and third molar teeth. Not to be confused with the buccal branch of the facial nerve which transmits motor information to the buccinator muscle, it courses between the two heads of the lateral pterygoid muscle, underneath the tendon of the temporalis muscle, under the masseter muscle to connect with the buccal branches of the facial nerve on the surface of the buccinator muscle. Small branches of the buccal nerve innervate the lateral pterygoid muscle, it gives sensory branches to the cheek. The facial nerve has buccal branches, which carry motor innervation to the buccinator muscle, a muscle of facial expression; this follows from the trigeminal supplying all muscles of mastication and the facial supplying all muscles of facial expression. Buccal nerve block is indicated for procedures involving the mucosa adjacent to the posterior molar teeth, such as the placement of a rubber dam clamp.

The injection site is distal and buccal to the third molar, with the needle penetrating 1-2mm as the nerve lies directly below the mucosa. A buccal nerve block is carried out after an inferior alveolar nerve block for specific procedures, such as extraction of mandibular molar teeth. "Nerve, buccal." Stedman's Medical Dictionary, 27th ed.. ISBN 0-683-40007-X Gray's Anatomy: The Anatomical Basis of Clinical Practice.. ISBN 0-443-07168-3Specific Anatomy figure: 27:03-03 at Human Anatomy Online, SUNY Downstate Medical Center MedEd at Loyola GrossAnatomy/h_n/cn/cn1/cnb3.htm lesson4 at The Anatomy Lesson by Wesley Norman cranialnerves at The Anatomy Lesson by Wesley Norman