Eilhard Mitscherlich was a German chemist, best remembered today for his discovery of the phenomenon of isomorphism in 1819. Mitscherlich was born at Neuende in the Lordship of Jever, his uncle, Christoph Wilhelm Mitscherlich, professor at the University of Göttingen, was in his day a celebrated scholar. Eilhard Mitscherlich was educated at Jever by the historian Friedrich Christoph Schlosser, in 1811 went to the University of Heidelberg devoting himself to philology, with an emphasis on the Persian language. In 1813 he went to Paris to seek permission to join the embassy which Napoleon I of France was establishing in Persia; the abdication of Napoleon Bonaparte in 1814 put an end to this, Mitscherlich resolved to study medicine in order that he might enjoy that freedom of travel allowed in the East to physicians. He began at Göttingen with the study of chemistry, this so arrested his attention that he gave up his idea to travel to Persia. From his days in Göttingen dates the treatise on certain parts of Eurasian history, compiled from manuscripts found in the university library and published in Persian and Latin in 1814, under the title Mirchondi historia Thaheridarum historicis nostris hucusque incognitorum Persiae principum.
In 1818 Mitscherlich worked in the laboratory of Heinrich Friedrich Link. There he studied phosphates, phosphites and arsenites, was able to confirm the conclusions of Jöns Jakob Berzelius as to their composition, his observation that corresponding phosphates and arsenates crystallize in the same form was the germ from which grew his theory of isomorphism, which theory was published in the proceedings of the Berlin Academy of Sciences in December 1819. In that same year Berzelius suggested Mitscherlich to the Prussian education minister Karl vom Stein zum Altenstein as successor to Martin Heinrich Klaproth at the University of Berlin. Altenstein did not carry out this suggestion, but he obtained for Mitscherlich a government grant to enable him to continue his studies in Berzelius' laboratory at the Karolinska Institutet in Stockholm. Mitscherlich returned to Berlin in 1821, in the summer of 1822 he delivered his first lecture as extraordinary professor of chemistry at the university. In 1823 Mitscherlich was elected as foreign member of the Royal Swedish Academy of Sciences.
In the course of investigating the slight differences discovered by William Hyde Wollaston in the angles of the rhombohedra of the carbonates isomorphous with calcite, Mitscherlich observed that this angle in the case of calcite varied with the temperature. On extending this inquiry to other allotropic crystals, he observed a similar variation, was thus led, in 1825, to the discovery that allotropic crystals, when heated, expand unequally in the direction of dissimilar axes. In the following year he discovered the change, produced by change of temperature, in the direction of the optic axes of selenite, his investigation in 1826, of the two crystalline modifications of sulfur threw much light on the fact that the two minerals calcite and aragonite have the same composition but different crystalline forms, a property which Mitscherlich called polymorphism. In 1833 Mitscherlich made a series of careful determinations of the vapor densities of a large number of volatile substances, confirming the law of Gay-Lussac.
In 1833-34, Mitscherlich investigated the synthesis of diethyl ether from sulfuric acid. Through his careful studies, he realized that the acid was not being consumed during the production of the ether, although the reaction would not proceed unless the acid was present. After reviewing Mitscherlich's findings, Swedish chemist Jöns Jacob Berzelius was led to coin the term "catalysis" for the acceleration or enablement of a chemical reaction by a substance that itself was not consumed in the reaction, he obtained selenic acid in 1827 and showed that its salts are isomorphous with the sulphates, while a few years he proved that the same thing is true of the manganates and the sulfates, of the permanganates and the perchlorates. He investigated the relation of benzene to other derivatives; as related by Gustav Rose Mitscherlich turned away from inorganic chemistry and devoted his attention to organic chemistry, starting out with an investigation of fuel and oil. Mitscherlich kept working on problems of organic chemistry until 1845.
His interest in mineralogy led him to study the geology of volcanic regions, he made frequent visits to the Eifel in an attempt to develop a theory on the cause of volcanism. He did not, publish any papers on the subject, though after his death his notes were arranged and published by J. L. A. Roth in the Memoirs of the Berlin Academy. Mitscherlich was an honorary member of all the great scientific societies, received the gold medal from the Royal Society of London for his discovery of the law of isomorphism, he was one of the few foreign associates of the French Institute. In 1855, Mitscherlichwas elected a Foreign Honorary Member of the American Academy of Arts and Sciences. In December 1861, symptoms of heart disease made their appearance, but Mitscherlich was able to carry on his academic work until December 1862, he died at Schöneberg near Berlin in 1863 and was buried in the St Matthäus Kirchhof Cemetery in Schöneberg close to the gravesites of Gustav Kirchhoff and Leopold Kronecker. Mitscherlich pu
Holzminden is a town in southern Lower Saxony, Germany. It is the capital of the district of Holzminden, it is located on the river Weser, which at this point forms the border with the state of North Rhine-Westphalia. Holzminden is first mentioned in the 9th century as Holtesmeni. However, the name did not at this time refer to the present city, but to the village of Altendorf, the "old village", incorporated into the city in 1922. During the reign of Louis the Pious, monks from the Abbey of Corbie in France came to this part of Germany and founded a daughter house at Hethis in the Solling; as it became clear that this site was unviable it was abandoned, a new monastery, Corbeia nova, opened close to the river. Old documents show; the settlement is believed to have come into being, along with other settlements in the vicinity, in the 6th-7th centuries. Other villages were subsequently abandoned as Holzminden was granted municipal liberties, allowing greater privileges to its inhabitants, attracting new settlers from the surrounding hinterland.
In 1200 the town was brought under the protection of the prince’s castle of Everstein, by 1245 it had received a charter. This was granted by the count of Everstein; the town's coat of arms shows the Everstein lion rampant within the open town gate. From 1408 the town belonged to the Welfen princes. From the 16th century until 1942, Holzminden therefore lay within Brunswick-Lüneburg. In 1640, during the Thirty Years' War, the town was destroyed by the Imperial troops, a blow from which it only recovered; until the 20th century Holzminden remained a provincial town of small holdings. During World War I, Holzminden was the site of a large civilian internment camp on the outskirts of the town, which held up to 10,000 Polish, Russian and French nationals, including women and children. Crafts and farming have long ceased to be the main town's sources of income. Holzminden is now a industrial town. In the late 19th century, Dr Wilhelm Haarmann began developing the scent and flavours industry. In 1874, with Ferdinand Tiemann, he succeeded in synthesising vanillin from coniferyl alcohol.
More products were subsequently developed. The modern successor of their enterprise is the Symrise factory: Holzminden is a centre of the flavour and fragrance ingredient industry, its products being used throughout the world in cosmetic and food manufacture; the large Stiebel Eltron company, which produces heating and hot water products, has its headquarters in Holzminden. Owens-Illinois conducts a glassworks in the town; as a part of the former territory of Brunswick, Holzminden maintains a Protestant tradition. The church of St. Pauls in Altendorf, dating from before 1200, is the oldest of the town's churches. In its unadorned simplicity it offers a serene place for contemplation. Other churches in the town are named after St. Michael, St. Thomas and St. Joseph; the Tilly House of 1609 is located on the Johannis Square. It has a fine Renaissance door. Johann Tserclaes, Count of Tilly, commander of the Imperial forces, is said to have spent a night here; the Reichspräsidentenhaus links the old part of the town with the Hafendamm and was opened in 1929.
The beautiful Glockenspiel is popular, plays well known tunes at set times. The steeple of the Lutheran church has become a symbol of Holzminden; the interior was remodelled in 1577. The Severinsche Haus is a richly decorated house dating from 1683, it is the largest of the bourgeois houses, is decorated with a distinctive weathercock, is known for its slanting floors. There is a good viewing platform on the Emperor William Tower, south of the town; the town museum The doll and toy museum HAWK, the Hochschule für angewandte Wissenschaft und Kunst, was founded in 1831/32 by Friedrich Ludwig Haarmann as the first college of architecture in Germany. The Bauschule is now a prominent feature of the town, many student activities, such as the traditional master's procession, are regular events on the Holzminden calendar. LSH, the Internat Solling, is a private boarding school founded in 1909 as part of an educational reform movement that sought to cultivate "Mind and Hand" equally; the campus occupies large parklike grounds on a western slope of the Solling.
Campe-Gymnasium. A Gymnasium is a top school for emphasizes academic learning and comparable to the British grammar school system or with prep schools in the United States; the other secondary schools are the Johannes-Falk-Schule. There are a Förderschule, Schule an der Weser and Anne-Frank-Schule. Holzminden is twinned with: Leven, Scotland August Hampe, German politician, Minister of Justice of the Braunschweig District. Erwin Böhme, World War I flying ace. Leopold Scherman, architect. Carl Wilhelm Gerberding and founder of Dragoco. Adolf Heusinger, German general and Chairman of the NATO Military Committee. Eberhard Itzenplitz, film director. Ulrich Brinkhoff Photographer and writer Robert Bunsen, chemist. Wilhelm Konrad Hermann Müller, a philologist of Germanic studies. Wilhelm Raabe, nov
Heidelberg University is a public research university in Heidelberg, Baden-Württemberg, Germany. Founded in 1386 on instruction of Pope Urban VI, Heidelberg is Germany's oldest university and one of the world's oldest surviving universities, it was the third university established in the Holy Roman Empire. Heidelberg has been a coeducational institution since 1899; the university consists of twelve faculties and offers degree programmes at undergraduate and postdoctoral levels in some 100 disciplines. Heidelberg comprises three major campuses: the humanities are predominantly located in Heidelberg's Old Town, the natural sciences and medicine in the Neuenheimer Feld quarter, the social sciences within the inner-city suburb Bergheim; the language of instruction is German, while a considerable number of graduate degrees are offered in English. As of 2017, 56 Nobel Prize winners have been affiliated with the university. Modern scientific psychiatry, psychopharmacology, psychiatric genetics, environmental physics, modern sociology were introduced as scientific disciplines by Heidelberg faculty.
1,000 doctorates are completed every year, with more than one third of the doctoral students coming from abroad. International students from some 130 countries account for more than 20 percent of the entire student body. Internationally renowned and ranked among Europe's top universities, Heidelberg is one of the most prestigious universities in the world, a German Excellence University, part of the U15, as well as a founding member of the League of European Research Universities and the Coimbra Group; the university's noted alumni include eleven domestic and foreign Heads of State or Heads of Government. The Great Schism of 1378 made it possible for Heidelberg, a small city and capital of the Electorate of the Palatinate, to gain its own university; the Great Schism was initiated by the election of two popes after the death of Pope Gregory XI in the same year. One successor the other in Rome; the German secular and spiritual leaders voiced their support for the successor in Rome, which had far-reaching consequences for the German students and teachers in Paris: they lost their stipends and had to leave.
Rupert I recognized the opportunity and initiated talks with the Curia, which led to a Papal Bull for foundation of a university. After having received, on 23 October 1385, permission from pope Urban VI to create a school of general studies, the final decision to found the university was taken on 26 June 1386 at the behest of Rupert I, Count Palatine of the Rhine; as specified in the papal charter, the university was modelled after University of Paris and included four faculties: philosophy, theology and medicine. On 18 October 1386 a special Pontifical High Mass in the Heiliggeistkirche was the ceremony that established the university. On 19 October 1386 the first lecture was held. In November 1386, Marsilius of Inghen was elected first rector of the university; the rector seal motto was semper apertus—i.e. "the book of learning is always open." The university grew and in March 1390, 185 students were enrolled at the university. Between 1414 and 1418, theology and jurisprudence professors of the university took part in the Council of Constance and acted as counselors for Louis III, who attended this council as representative of the emperor and chief magistrate of the realm.
This resulted in establishing a good reputation for its professors. Due to the influence of Marsilius, the university taught the nominalism or via moderna. In 1412, both realism and the teachings of John Wycliffe were forbidden at the university but around 1454, the university decided that realism or via antique would be taught, thus introducing two parallel ways; the transition from scholastic to humanistic culture was effected by the chancellor and bishop Johann von Dalberg in the late 15th century. Humanism was represented at Heidelberg University by the founder of the older German Humanistic School Rudolph Agricola, Conrad Celtes, Jakob Wimpfeling, Johann Reuchlin. Æneas Silvius Piccolomini was chancellor of the university in his capacity of provost of Worms, always favored it with his friendship and good-will as Pope Pius II. In 1482, Pope Sixtus IV permitted laymen and married men to be appointed professors in the ordinary of medicine through a papal dispensation. In 1553, Pope Julius III sanctioned the allotment of ecclesiastical benefice to secular professors.
Martin Luther's disputation at Heidelberg in April 1518 made a lasting impact, his adherents among the masters and scholars soon became leading Reformationists in Southwest Germany. With the Electorate of the Palatinate turn to the Reformed faith, Otto Henry, Elector Palatine, converted the university into a calvinistic institution. In 1563, the Heidelberg Catechism was created under collaboration of members of the university's divinity school; as the 16th century was passing, the late humanism stepped beside Calvinism as a predominant school of thought. It developed into a cultural and academic center. However, with the beginning of the Thirty Years' War in 1618, the intellectual and fiscal wealth of the university declined. In 1622, the then-world-famous Bibliotheca Palatina was stolen from the University Cathedral and taken to Rome; the reconstruction e
Göttingen is a university city in Lower Saxony, the capital of the eponymous district. It is run through by River Leine. At the start of 2017, the population was 134,212; the origins of Göttingen lay in a village called Gutingi, first mentioned in a document in 953 AD. The city was founded northwest of this village, between 1150 and 1200 AD, adopted its name. In medieval times the city was a member of hence a wealthy town. Today, Göttingen is famous for its old university, founded in 1734 and became the most visited university of Europe. In 1837, seven professors protested against the absolute sovereignty of the kings of Hanover, its alumni include some well-known historical figures: the Brothers Grimm, Heinrich Ewald, Wilhelm Eduard Weber and Georg Gervinus. German Chancellors Otto von Bismarck and Gerhard Schröder attended law school at the Göttingen University. Karl Barth held his first professorship here; some of the most famous mathematicians in history, Carl Friedrich Gauss, Bernhard Riemann and David Hilbert, were professors at Göttingen.
Like other university towns, Göttingen has developed its own quaint traditions. On the day they are awarded their doctorate degrees, students are drawn in handcarts from the Great Hall to the Gänseliesel-Fountain in front of the Old Town Hall. There they have to kiss the statue of the Gänseliesel; this practice is forbidden, but the law is not enforced. She is considered the most kissed girl in the world. Nearly untouched by Allied bombing in World War II, the inner city of Göttingen is now an attractive place to live with many shops and bars. For this reason, many university students give Göttingen a youthful feel. In 2003, 45 % of the inner city population was only between 30 years of age. Commercially, Göttingen is noted for its production of optical and precision-engineered machinery, being the seat of the light microscopy division of Carl Zeiss, Inc. and a main site for Sartorius AG which specialises in bio-technology and measurement equipment—the region around Göttingen advertises itself as "Measurement Valley".
Unemployment in Göttingen was 12.6% in 2003 and is now 7%. The city's railway station to the west of the city centre is on Germany's main north-south railway. Göttingen has two professional basketball teams. For the 2007-08 season, both teams will play in the 1st division; the origins of Göttingen can be traced back to a village named Gutingi to the immediate south-east of the eventual city. The name of the village derives from a small stream, called the Gote, that once flowed through it. Since the ending -ing denoted "living by", the name can be understood as "along the Gote". Archaeological evidence points towards a settlement as early as the 7th century, it is first mentioned in a document by the Holy Roman Emperor Otto I in 953 AD, in which the emperor gives some of his belongings in the village to the Moritz monastery in Magdeburg. Archaeological findings point to extensive commercial relations with other regions and a developed craftsmanship in this early period. In its early days, Gutingi was overshadowed by Grona documented from the year 915 AD as a newly built fortress, lying opposite Gutingi on a hill west of the River Leine.
It was subsequently used as an Ottonian imperial palace, with 18 visits of kings and emperors documented between 941 and 1025 AD. The last Holy Roman Emperor to use the fortress of Grona, Heinrich II had a church built in the neighbouring Gutingi, dedicated to Saint Alban; the current church building that occupies this site, the St. Albani Church, was built in 1423; the fortress lost its function as a palace in 1025, after Heinrich II died there, having retreated to it in ill health. It was subsequently used by the lords of Grone; the fortress was destroyed by the citizens of Göttingen between 1323 and 1329, razed to the ground by Duke Otto I during his feuds with the city of Göttingen in 1387. With time, a trading settlement started to form at the river crossing of the Leine to the west of the village, from which it took its name, it is this settlement, given city rights. The original village remained recognisable as a separate entity until about 1360, at which time it was incorporated within the town's fortification.
It is the present city was founded between 1150 and 1180, although the exact circumstances are not known. It is presumed that Duke of Saxony and Bavaria, founded the city; the configuration of the streets in the oldest part of the town is in the shape of a pentagon, it has been proposed that the inception of the town followed a planned design. At this time, the town was known by the name Gudingin or Gotingen, its inhabitants obeyed welfish ownership and ruling rights, the first Göttingen burghers are mentioned, indicating that Göttingen was organised as a true city. It was not, however, a Free Imperial City, but subject to the Welf dukes of Brunswick-Lüneburg. Henry the Elder of Brunswick, eldest son of Henry the Lion and brother of the Holy Roman Emperor Otto IV, is given as the lord over Göttingen between 1201 and 1208; the original Welf residency in the town consisted of a farm building and the stables of the Welf dukes, which occupied the oldest part of the city's fortifications built prior to 1250.
In its early days, Göttingen became involved in the conflicts of t
Giessen, spelled Gießen in German (German pronunciation: ], is a town in the German federal state of Hesse, capital of both the district of Giessen and the administrative region of Giessen. The population is 86,000, with 24,000 university students; the name comes from Giezzen, as it was first referred to in 1197, which refers to the position of the town between several rivers and streams. The largest river in Giessen is the Lahn, which divides the town in two parts 50 kilometres north of Frankfurt am Main. In 1969, the town hosted the ninth Hessentag state festival. Giessen came into being as a moated castle in 1152 built by Count Wilhelm von Gleiberg, although the history of the community in the northeast and in today's suburb called "Wieseck" dates back to 775; the town became part of Hesse-Marburg in 1567, passing to Hesse-Darmstadt in 1604. The University of Giessen was founded in 1607. Giessen was included within the Grand Duchy of Hesse created in 1806 during the Napoleonic Wars. After the First World War, it was part of the People's State of Hesse.
During the Second World War, a subcamp of the Buchenwald concentration camp was in the Heil- und Pflegeanstalt Licher Straße. Heavy bombing destroyed about 75 percent of Gießen in 1944, including most of the town's historic buildings, it became part of the modern state of Hesse after the war. In 1977, Giessen was merged with the neighbouring city Wetzlar to form the new city of Lahn. However, this attempt to reorganize the administration was reversed in 1979, it was bounded to Darmstadt between 1945 and 1981 until Giessen was founded on 1 January 1981. A U. S. military base was located in Giessen after the Second World War. The U. S. Army Garrison of Gießen had a population of 800 Americans; the base is a converted German Army Air Field, reflected in some of the buildings including the housing area. A theatre, known as the Keller Theatre, is a converted German Army Officers' Club; as of 28 September 2007, the Giessen Depot and all other U. S. facilities in the greater Giessen area were turned back to local German authorities.
The former U. S. Army buildings were used to house refugees after the large intake of 2016. After the war, the city was twinned with Winchester, UK. Giessen is twinned with: Akademischer Forstgarten Gießen, botanical gardens Botanischer Garten Gießen, established in 1609, is the oldest botanical garden in Germany still at its original location. Old Cemetery, is the resting place of Hugo von Ritgen. Liebig-Museum was established in 1920 to honor the chemist Justus von Liebig. Mathematikum was established in 2002. University of Giessen Rubber Island is a residential area near the Lahn River. Giessen is home to the basketball club Giessen 46ers, five-time champion of the Basketball Bundesliga, its home games take place at the Sporthalle Gießen-Ost. Giessen has an American football team called Giessen Golden Dragons. In Giessen the Catholic Scouts of Europe were founded in 1975. Samuel Adler, a noted rabbi in the United States, attended the University of Giessen Annika Beck, professional tennis player Stefan Bellof, Formula One and Sportscar driver, killed during a race held in Spa-Francorchamps Christa Blanke, founder of Animals' Angels e.
V. Volker Bouffier, politician Georg Büchner studied two years at the University of Gießen Daniel Davari, Iranian footballer. Walter Dornberger, rocket scientist Peter Düttmann, Luftwaffe Ace Landgravine Elisabeth Amalie of Hesse-Darmstadt, Electress Palatine, ancestress of most of today's royals Charles Friedek, triple jumper, gold medallist at the 1999 World Championships in Athletics Adolph Hansen and professor at University of Giessen Fritz Heichelheim, economic historian Juli, rock band Friedrich Kellner, Chief Regional Auditor in Giessen 1948-1950, Chief Justice Inspector of Laubach, where he wrote his secret WWII diary; the Holocaust Research Unit of Justus Liebig University of Giessen has established the Kellner Project Karl Kling, Racing driver and head of Mercedes-Benz Motorsport Jonathan Koch, rower Chris Liebing techno/electronic music producer and DJ Justus von Liebig, professor. The official name of the University of Giessen is now Justus Liebig University Wilhelm Liebknecht, founder of the Social Democratic Party of Germany, was born on March 29, 1826 in Giessen Sigmund Livingston, American lawyer and first president of the Anti-Defamation League Christopher Ludwick Baker General for the American Revolutionary War Army - Philadelphia Wangari Maathai, Nobel Laureate 2004 Alfred Milner, British statesman Demis Nikolaidis, Greek footballer James J. O'Donnell, American scholar and University administrator, born in Giessen Albert Osswald, politician Wilhelm Conrad Röntgen, professor of physics from 1879 until 1888 at the University of Giessen.
He was buried at the "Alte Friedhof", where his tomb can still be found Johann Georg Rosenmüller, professor of theology at the university Til Schweiger, actor and producer. Grew up, went to school and started studying in Giessen Wilhelm Sievers, explorer, professor at the university Henrietta Skelton, social reformer, organizer, lecturer Marie Wittich, opera singer Willy Zschietzschmann, Classical archeologist and author Ernst Dieffenbach
Viktor Meyer was a German chemist and significant contributor to both organic and inorganic chemistry. He is best known for inventing an apparatus for determining vapour densities, the Viktor Meyer apparatus, for discovering thiophene, a heterocyclic compound, he is sometimes referred to as a name used in some of his publications. Viktor Meyer was born in Berlin in 1848, the son of trader and cotton printer Jacques Meyer and mother, Bertha, his parents were Jewish, though he was not raised in the Jewish faith. He was confirmed in a Reform Jewish congregation, he married a Christian woman, Hedwig Davidson, raised his children as such. He entered the gymnasium at the age of ten in the same class as his two-year older brother Richard. Although he had excellent science skills his wish to become an actor was based on his love for poetry. At a visit from his brother Richard, studying chemistry at the University of Heidelberg, he became attracted to chemistry. In 1865, when not yet 17 years old but pushed by his parents, Meyer began studying chemistry at the University of Berlin, the same year that August Wilhelm von Hofmann succeeded Eilhard Mitscherlich as the Chair of Chemistry there.
After one semester, Meyer went to Heidelberg to work under Robert Bunsen, where he heard lectures on organic chemistry by Emil Erlenmeyer. As no research was required under Bunsen at the time, Meyer received his doctorate in 1867, at the age of 19; this opened the doors to a successful career in which he became one of the most important chemists of his time. Meyer stayed one year with Bunsen for an area wide analysis of spring water. Besides this he was able to teach some Ph. D. students. In Berlin he joined the group of Adolf Baeyer, one of his best friends in life, attacking among other problems that of the composition of camphor. At the age of 23 on Baeyer's recommendation, Meyer was engaged by Fehling as his assistant at Stuttgart Polytechnic, but within a year he left to succeed Johannes Wislicenus at Zurich. There he remained for thirteen years, it was during this period that he devised his well-known method for determining vapour densities, carried out his experiments on the dissociation of the halogens.
In 1882, on the death of Wilhelm Weith, professor of chemistry at Zurich University, he undertook to continue the lectures on benzene derivatives, this led him to the discovery of thiophen. In 1885 he was chosen to succeed Hans Hübner in the professorship of chemistry at Göttingen University, where stereo-chemical questions engaged his attention, he died on 8 August 1897. Overworked and overtaxed, Meyer's mental status suffered, leading to several minor and major nervous breakdowns during the last years of his life, he always failed to recover yet continued working. He took pills to fall asleep. In one of his depressions, Meyer decided to take his own life, committed suicide by taking cyanide, he died at the age of 48 during the night of 7–8 August 1897 in Heidelberg. Synthesis of aromatic carboxylic acids from sulfonic acid and formates. Nitroalkanes from alkyl iodides and silver nitrite, used to distinguish 1°, 2°, 3° alcohols, known as the Victor Meyer test. Discovery of nitrolic acids. Development of a method to distinguish primary and tertiary nitroalkanes.
Starting with studying physical chemistry in 1876, Meyer created a new method for determining gas density in 1878. This method allowed him to demonstrate how arsenious oxide vapours corresponded to the formula As4O6, that mercury and cadmium yielded monatomic vapours, that halogen molecules dissociated into atoms on heating, a phenomenon which he studied until his death; the Victor Meyer apparatus measures the volume of a volatilized substance from which the vapor density of the gas can be derived and the relative mass. Proposing glucose is an aldehyde and not a ketone, hereby van't Hoff. Synthesis of aldoximes and ketoximes from hydroxylamine and aldehydes or ketones, hereby discovering a new structural identification and elucidation method. Identification of thiophene as a contaminant in benzene derived from coal. Benzene produced by decarboxylation of benzoic acid did not contain this impurity. First reliable synthesis of pure sulfur mustard Coining of the concepts of stereochemistry and dipole in 1888.
Meyer had always been interested in stereochemical problems and was one of the first ones to instruct his pupils with van't Hoff's theory of asymmetric carbon and the Hantzsch-Werner theory. Discovery of iodoso compounds in 1892 by reacting o-iodobenzoic acid with nitric acid. Observation that ortho-substituted benzoic acid derivatives are esterified with difficulty; this principle is now known as the Victor Meyer esterification law and was discovered in an attempt to esterify o-iodosobenzoic acid. Discovery of iodonium compounds by reacting iodosobenzene. Meyer wrote several notable books: Tabellen zur qualitativen Analyse Pyrochemische Untersuchungen Die Thiophengruppe Chemische Probleme der Gegenwart Ergebnisse und Ziele der Stereochemischen Forschung Lehrbuch der organischen Chemie Digital editions by the University and State Library Düsseldorf Märztage im kanarischen
Geology is an earth science concerned with the solid Earth, the rocks of which it is composed, the processes by which they change over time. Geology can include the study of the solid features of any terrestrial planet or natural satellite such as Mars or the Moon. Modern geology overlaps all other earth sciences, including hydrology and the atmospheric sciences, so is treated as one major aspect of integrated earth system science and planetary science. Geology describes the structure of the Earth on and beneath its surface, the processes that have shaped that structure, it provides tools to determine the relative and absolute ages of rocks found in a given location, to describe the histories of those rocks. By combining these tools, geologists are able to chronicle the geological history of the Earth as a whole, to demonstrate the age of the Earth. Geology provides the primary evidence for plate tectonics, the evolutionary history of life, the Earth's past climates. Geologists use a wide variety of methods to understand the Earth's structure and evolution, including field work, rock description, geophysical techniques, chemical analysis, physical experiments, numerical modelling.
In practical terms, geology is important for mineral and hydrocarbon exploration and exploitation, evaluating water resources, understanding of natural hazards, the remediation of environmental problems, providing insights into past climate change. Geology is a major academic discipline, it plays an important role in geotechnical engineering; the majority of geological data comes from research on solid Earth materials. These fall into one of two categories: rock and unlithified material; the majority of research in geology is associated with the study of rock, as rock provides the primary record of the majority of the geologic history of the Earth. There are three major types of rock: igneous and metamorphic; the rock cycle illustrates the relationships among them. When a rock solidifies or crystallizes from melt, it is an igneous rock; this rock can be weathered and eroded redeposited and lithified into a sedimentary rock. It can be turned into a metamorphic rock by heat and pressure that change its mineral content, resulting in a characteristic fabric.
All three types may melt again, when this happens, new magma is formed, from which an igneous rock may once more solidify. To study all three types of rock, geologists evaluate the minerals; each mineral has distinct physical properties, there are many tests to determine each of them. The specimens can be tested for: Luster: Measurement of the amount of light reflected from the surface. Luster is broken into nonmetallic. Color: Minerals are grouped by their color. Diagnostic but impurities can change a mineral’s color. Streak: Performed by scratching the sample on a porcelain plate; the color of the streak can help name the mineral. Hardness: The resistance of a mineral to scratch. Breakage pattern: A mineral can either show fracture or cleavage, the former being breakage of uneven surfaces and the latter a breakage along spaced parallel planes. Specific gravity: the weight of a specific volume of a mineral. Effervescence: Involves dripping hydrochloric acid on the mineral to test for fizzing. Magnetism: Involves using a magnet to test for magnetism.
Taste: Minerals can have a distinctive taste, like halite. Smell: Minerals can have a distinctive odor. For example, sulfur smells like rotten eggs. Geologists study unlithified materials, which come from more recent deposits; these materials are superficial deposits. This study is known as Quaternary geology, after the Quaternary period of geologic history. However, unlithified material does not only include sediments. Magmas and lavas are the original unlithified source of all igneous rocks; the active flow of molten rock is studied in volcanology, igneous petrology aims to determine the history of igneous rocks from their final crystallization to their original molten source. In the 1960s, it was discovered that the Earth's lithosphere, which includes the crust and rigid uppermost portion of the upper mantle, is separated into tectonic plates that move across the plastically deforming, upper mantle, called the asthenosphere; this theory is supported by several types of observations, including seafloor spreading and the global distribution of mountain terrain and seismicity.
There is an intimate coupling between the movement of the plates on the surface and the convection of the mantle. Thus, oceanic plates and the adjoining mantle convection currents always move in the same direction – because the oceanic lithosphere is the rigid upper thermal boundary layer of the convecting mantle; this coupling between rigid plates moving on the surface of the Earth and the convecting mantle is called plate tectonics. The development of plate tectonics has provided a physical basis for many observations of the solid Earth. Long linear regions of geologic features are explained as plate boundaries. For example: Mid-ocean ridges, high regions on the seafloor where hydrothermal vents and volcanoes exist, are seen as divergent boundaries, where two plates move apart. Arcs of volcanoes and earthquakes are theorized as convergent boundaries, where one plate subducts, or moves, under another. Transform boundaries, such as the San Andreas Fault system, resulted in widespread powerful earthquakes.
Plate tectonics has provided a mechan