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Spectrophotometry

In chemistry, spectrophotometry is the quantitative measurement of the reflection or transmission properties of a material as a function of wavelength. It is more specific than the general term electromagnetic spectroscopy in that spectrophotometry deals with visible light, near-ultraviolet, near-infrared, but does not cover time-resolved spectroscopic techniques. Spectrophotometry is a tool that hinges on the quantitative analysis of molecules depending on how much light is absorbed by colored compounds. Spectrophotometry uses photometers, known as spectrophotometers, that can measure a light beam's intensity as a function of its color. Important features of spectrophotometers are spectral bandwidth, the percentage of sample-transmission, the logarithmic range of sample-absorption, sometimes a percentage of reflectance measurement. A spectrophotometer is used for the measurement of transmittance or reflectance of solutions, transparent or opaque solids, such as polished glass, or gases. Although many biochemicals are colored, as in, they absorb visible light and therefore can be measured by colorimetric procedures colorless biochemicals can be converted to colored compounds suitable for chromogenic color-forming reactions to yield compounds suitable for colorimetric analysis.

However, they can be designed to measure the diffusivity on any of the listed light ranges that cover around 200 nm - 2500 nm using different controls and calibrations. Within these ranges of light, calibrations are needed on the machine using standards that vary in type depending on the wavelength of the photometric determination. An example of an experiment in which spectrophotometry is used is the determination of the equilibrium constant of a solution. A certain chemical reaction within a solution may occur in a forward and reverse direction, where reactants form products and products break down into reactants. At some point, this chemical reaction will reach a point of balance called an equilibrium point. In order to determine the respective concentrations of reactants and products at this point, the light transmittance of the solution can be tested using spectrophotometry; the amount of light that passes through the solution is indicative of the concentration of certain chemicals that do not allow light to pass through.

The absorption of light is due to the interaction of light with the electronic and vibrational modes of molecules. Each type of molecule has an individual set of energy levels associated with the makeup of its chemical bonds and nuclei, thus will absorb light of specific wavelengths, or energies, resulting in unique spectral properties; this is based upon its distinct makeup. The use of spectrophotometers spans various scientific fields, such as physics, materials science, biochemistry, Chemical Engineering, molecular biology, they are used in many industries including semiconductors and optical manufacturing and forensic examination, as well in laboratories for the study of chemical substances. Spectrophotometry is used in measurements of enzyme activities, determinations of protein concentrations, determinations of enzymatic kinetic constants, measurements of ligand binding reactions. A spectrophotometer is able to determine, depending on the control or calibration, what substances are present in a target and how much through calculations of observed wavelengths.

In astronomy, the term spectrophotometry refers to the measurement of the spectrum of a celestial object in which the flux scale of the spectrum is calibrated as a function of wavelength by comparison with an observation of a spectrophotometric standard star, corrected for the absorption of light by the Earth's atmosphere. Invented by Arnold O. Beckman in 1940, the spectrophotometer was created with the aid of his colleagues at his company National Technical Laboratories founded in 1935 which would become Beckman Instrument Company and Beckman Coulter; this would come as a solution to the created spectrophotometers which were unable to absorb the ultraviolet correctly. He would start with the invention of Model A, it would be found that this did not give satisfactory results, therefore in Model B, there was a shift from a glass to a quartz prism which allowed for better absorbance results. From there, Model C was born with an adjustment to the wavelength resolution which ended up having three units of it produced.

The last and most popular model became Model D, better recognized now as the DU spectrophotometer which contained the instrument case, hydrogen lamp with ultraviolent continuum and a better monochromator. It was produced from 1941 to 1976 where the price for it in 1941 was US$723. In the words of Nobel chemistry laureate Bruce Merrifield, it was "probably the most important instrument developed towards the advancement of bioscience."Once it became discontinued in 1976, Hewlett-Packard created the first commercially available diode-array spectrophotometer in 1979 known as the HP 8450A. Diode-array spectrophotometers differed from the original spectrophotometer created by Beckman because it was the first single-beam microprocessor-controlled spectrophotometer that scanned multiple wavelengths at a time in seconds, it irradiates the sample with polychromatic light which the sample absorbs depending on its properties. It is transmitted back by grating the photodiode array which detects the wavelength region of the spectrum.

Since the creation and implementation of spectrophotometry devices has increased immensely and has become one of the most innovative instruments

Bdote Memory Map

The Bdote Memory Map is an interactive online map and website by which the Dakota people trace their history and passed down memory of the region, now referred to as the Twin Cities area in Minnesota. It allows viewers to explore the history of the region. With video and other multimedia forms, the map provides the voices of Native speakers to tell their personal and ancestral stories of the region at the junction of the Mississippi and Minnesota Rivers, known by the Dakota people as Bdote, meaning "where the two waters come together". Mona Smith, a Sisseton-Wahpeton Dakota videographer, helped create the Bdote Memory Map in partnership with the Minnesota Humanities Center; the Memory Map grew out of a 2006 multimedia exhibition Mona Smith put on at the Ancient Traders Gallery entitled "City Indians," reflecting the ironic term attached to Dakota living in the Twin Cities. Smith, wished to express how the cities grew in areas that were their land, the bdote. After the Minnesota Humanities Center extended funding, what began as a map of the region where Native Americans could attach post-it notes of their memories became the online Bdote Memory Map.

When first entering the website, a four sided wheel, representing the traditional Dakota Medicine Wheel, prompts the visitor to explore the map or other writings on the Dakota and information about the website. The map itself is an interactive map of the Bdote region. There are several physical markers on the map that viewers are encouraged to click on, from which a specific memory or story will emerge; these can take the form of videos, audio recordings and more from indigenous writers, elders and experts. Many of these writings will prompt visitors with questions to reflect on the meaning of what they have learned; the website additionally includes teachers' guides for instruction on indigenous peoples in the classroom, informational resources about the Dakota, American Indian legal histories, as well as a variety of historical maps of both the Bdote and the larger Americas as well. The Bdote Memory Map is still soliciting indigenous memories and stories of the Bdote region today to add to its platform.

Smith is hoping to expand the map's area of coverage to include indigenous stories from throughout the entire Mississippi region down to Louisiana. Official website

Bourne & Shepherd

Bourne & Shepherd was an Indian photographic studio and one of the oldest established photographic businesses in the world. Established in 1863, at its peak, it was the most successful commercial firm in 19th-and early 20th-century India, with agencies all over India, outlets in London and Paris, ran a mail order service. A devastating fire in 1991 destroyed much of the studio's photographic archive and resulted in a severe financial loss to the firm; the long-term impact of the fire, legal difficulties with the Indian government, which owned the studio building, the increasing dominance of digital technology forced the studio's closure in June 2016. At its closure, the studio had operated continuously for 176 years. Though some sources consider its inception to be 1862, when noted British photographers, Charles Shepherd established a photographic studio, with Arthur Robertson, called'Shepherd & Robertson' in Agra, which moved to Shimla and became the part of ‘Howard, Bourne & Shepherd’, set up by Samuel Bourne, Charles Shepherd, along with William Howard, first established in Shimla around 1863, Howard's studio in Kolkata dates back to 1840, where it is still operational today, at Esplanade Row, in Esplanade, Kolkata under the same name.

Today some of their earlier work is preserved at Cambridge University Library, the National Portrait Gallery, the National Geographic Society's Image Collection and the Smithsonian Institution. Samuel Bourne came to India in 1863, set up a partnership with an established Calcutta photographer, William Howard, they set up a new studio'Howard & Bourne' at Shimla. William Howard had set up the Calcutta studio in 1840. Meanwhile, Charles Shepherd, had established a photographic studio, with Arthur Robertson, called'Shepherd & Robertson' in Agra in 1862, subsequently he too moved to Shimla in 1864. At some point Robertson left the business and Charles Shepherd, joined Bourne company to form'Howard, Bourne & Shepherd'. In 1863, he made first of three major Himalayan photographic expeditions, followed by another one 1866, prior to which he took an expedition to Kashmir in 1864, in fact all photographic histories of that era carry his works, he was known to travel heavy, as he moved with a large retinue of 42 coolies carried his cameras, darkroom tent and chests of chemicals and glass plates, he was to become one of India's greatest photographers of that era.

Charles on the other hand became known as a master printer, he stayed back in Shimla and managed the commercial distribution and printing aspects of the business. Through the 1860s, Bourne's work was exhibited in public exhibition in Europe and was part of the Paris Universal Exposition in 1867, he wrote several despatches for'The British Journal of Photography between' 1863–1870, the company became an avid provider of the Indian landscape views to the common visitors to the country and to Britishers back home, not just survived but the thrived in an era of fierce competition between commercial photographers. In 1866 after the departure of Howard, the company became'Bourne & Shepherd'. In 1867 Bourne returned to England to get married and came back to run the new branch in Calcutta, soon it became the company premier photographic studios in India, at their peak their work was retailed throughout the subcontinent by agents and in Britain through wholesale distributors, were patronised by the upper echelons of the British Raj as well as Indian royalty, so much so that at one point no official engagement, investiture or local durbar was considered complete without being first captured Bourne & Shepherd photographers.

In 1870, the year when Bourne went back to England and Shepherd were operating from Shimla and Calcutta. Soon he started cotton-doubling business at Nottingham, founded the Britannia Cotton Mills, become a local magistrate, he sold off his shares in studios, left commercial photography all together. After Bourne's departure, new photographic work was undertaken by Colin Murray from 1840 to 84, following which in the 1870s Charles Shepherd continued to photograph and at least sixteen Europeans are listed as assistants; the Bombay branch was opened in about 1876, operated by Charles Shepherd until his own departure from India around 1879, the branch continued operations till about 1902. In 1880, they brought their services to as far as Lahore for a month, where they advertised in a local newspaper, in fact newspaper advertising has been a primary reason of the success of many photographers of that era. Soon their work was retailed throughout the subcontinent by agents and in Britain through wholesale distributors.

Between 1870 and 1911 the firm sent photographers to Ceylon, Burma and Singapore, had become Art Publishers, with titles like'Photographs of Architecture of Gujarat and Rajputana', were now employing Indian photographers as well. In 1911, they were the official photographers of the Delhi Durbar held to commemorate the coronation of King George V and Queen Mary as Emperor and Empress of India, where they were given the title,'Kaiser-e-Hind' which they still use as part of their official letterhead. During World Wars the studio thrived on the contracts for photographing Indian and American services personnel. In the following years, the studio changed hands several times, so much so the sequence of owners has been all but lost, however the last European owner, Arthur Musselwhite who took over the studio in t

Shades of azure

Azure is a variation of blue, described as the color of the sky on a clear day. On the RGB color wheel, "azure" is defined as the color at 210 degrees, i.e. the hue halfway between blue and cyan. In the RGB color model, used to create all the colors on a television or computer screen, azure is created by adding a little green light to blue light; the complementary color of azure is orange. In the X11 color system which became a standard for early web colors, azure is depicted as a pale cyan or white cyan. All of the colors shown below in the section variations of azure are referenced as having a hue code of between 195 and 225, signifying that these colors are tones of azure; the only exception, as noted below, is the web color azure which, with a color code of 180, is a tone of cyan. Speaking, according to the mathematical logic of the RGB color wheel, indigo colors are those colors with hue codes of between 255 and 225, azure colors are those colors with hue codes of between 195 and 225, cyan colors are those colors with hue codes of between 165 and 195.

Displayed at right is the web color called azure. In an artistic context, this color would be called azure mist; the web color Alice blue is a pale tint of azure. Displayed at right is the web color light sky blue. Baby blue is known as one of the pastel colors; this color is associated with baby boys in Western culture. The first recorded use of baby blue as a color name in English was in 1892. Displayed at right is the web color sky blue; the first recorded use of sky blue as a color name in English was in 1728 in the Cyclopædia of Ephraim Chambers. Prior to the Chambers reference, the color had first been used in 1585 in a book by Nicolas de Nicolay where he stated "the tulbant of the merchant must be skie coloured". Deep sky blue is an azure-cyan color associated with deep sky blue. Deep sky blue is a web color; this color is on the color wheel halfway between cyan. The traditional name for this color is Capri; the first use of Capri as a color name in English was in 1920. The color Capri in general is named for the azure-cyan color of the Mediterranean Sea around the island of Capri off Italy, the site of several villas belonging to the Roman Emperor Tiberius, including his imperial residence in his years, the Villa Jovis.

The color Capri is named after the color of the Blue Grotto on the island of Capri as it appears on a bright sunny day. Today the island of Capri is a resort island popular with tourists; the name deep sky blue for this color did not come into use until the promulgation of the X11 color list in 1987. The name Capri is still used for this color as well as the name deep sky blue. Maya blue was a pigment used by the Mayan civilization. At right is displayed the color jordy blue; the color name jordy blue has been in use since 2001, when this color was promulgated as one of the colors on the Xona.com Color List. Columbia blue is a medium light tone of azure named after Columbia University; the typical Columbia blue is defined by Pantone Columbia Blue. At right is displayed the color picton blue; the color name picton blue dates back to at least 2001, came into wider use when the Resene Paints colors were used as one of the sources for the Xona Games Color List. Displayed at right is the color United Nations blue.

The color resembles the shade of blue seen on the flag of the United Nations. At right is displayed the web color cornflower blue; the color bleu. Bleu de France is a color, associated in heraldry with the Kings of France since the 12th century. At right is displayed the color Dodger blue. Brandeis blue is the tone of azure used in association with Brandeis University; the university administration defines Brandeis blue as corresponding to the Pantone color of 294 or the process color of 100c 86m 14y w24k. The color true blue is a deep tone of azure, the color of the uniforms of the sports teams of UCLA, it is one of the shades of blue used by the Los Angeles Chargers though they use the name powder blue. The color tang blue is a deep tone of azure, the color of royal blue tang fish; the web color royal blue is a rich tone of azure. Displayed at right is the color celestial blue; the first recorded use of celestial blue as a color name in English was in 1535. The source of this color is the Plochere Color System, a color system formulated in 1948, used by interior designers.

Displayed at right is the color vista blue. The source of this color is the "Pantone Textile Paper eXtended" color list, color #15-3930 TPX—Vista Blue. Displayed at right is the color Silver Lake blue; the source of this color is the "Pantone Textile Paper eXtended" color list, color #17-4030 TPX—Silver Lake Blue. Tufts blue is the tone of azure used in association with Tufts University. Honolulu blue is the tone of azure used in association with the Detroit Lions football team; the first recorded use of cerulean as a color name in English was in 1590. The word is derived from the Latin word caeruleus, "dark blue, blue, or blue-green", which in turn derives from caelulum, diminutive of caelum, "heaven, sky". Displayed at right is the color air force blue known as RAF blue; this is the tone of air force blue used by the Royal Air Force, the first air force to choose an "air force blue" color by which to identify itself, in 1920. The color "air force blue" is a medium tone of azure since it has a hue code of 204, a hue code between 195 and 225, signifying a tone of azure.

Steel blue is a grayish tone of azu

Malcolm Menin

Malcolm James Menin was Bishop of Knaresborough from 1986 to 1997. Menin was educated at the Dragon School and University College, Oxford before studying for ordination at Cuddesdon College, Oxford. After curacies in Portsmouth and Fareham he was appointed vicar of St James's Norwich in 1962, an area which he was to be associated with for much of the rest of his life, he was appointed as be Rural Dean of Norwich in 1981. In 1982 he was appointed an honorary canon of Norwich Cathedral and appointment as the suffragan Bishop of Knaresborough in 1986. On retirement, he returned to Norwich where he remains active in church life

Ilona Korstin

Ilona Kalyuvna Korstin is a retired Russian basketball forward of Estonian origin, who competed for her native Russia at the 2004 Summer Olympics, the 2008 Summer Olympics and the 2012 Summer Olympics, winning two bronze medals. She ended her career in 2013, she is CEO at the VTB United League Olympics Bronze Medal: 2004, 2008 World Championship Silver Medal: 2002, 2006 EuroBasket: 2003, 2007, 2011 Bourges BasketEuroleague: 2001 Ligue Féminine: 1999, 2000VBM-SGAU Samara Euroleague: 2005 Russian Premier League: 2004, 2005, 2006 Russian Cup: 2004, 2006, 2007, 2008 World League: 2003, 2004, 2005, 2007Spartak M. R. VidnojeEuroleague: 2010 Europe SuperCup: 2009, 2010Dynamo MoscowEuroCup: 2013 Honored Master of Sports of Russia Medal of the Order For Merit to the Fatherland, 1st class - for outstanding contribution to the development of physical culture and sports, high achievements in sports at the Games of the XXIX Olympiad in Beijing in 2008 Profile Official website