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SUMMARY / RELATED TOPICS

Filtration

Filtration is a physical, biological or chemical operation that separates solid matter and fluid from a mixture with a filter medium that has a complex structure through which only the fluid can pass. Solid particles that cannot pass through the filter medium are described as oversize and the fluid that passes through is called the filtrate. Oversize particles may form a filter cake on top of the filter and may block the filter lattice, preventing the fluid phase from crossing the filter, known as blinding; the size of the largest particles that can pass through a filter is called the effective pore size of that filter. The separation of solid and fluid is imperfect. Filtration occurs both in engineered systems. Filtration is used to separate particles and fluid in a suspension, where the fluid can be a liquid, a gas or a supercritical fluid. Depending on the application, either one or both of the components may be isolated. Filtration, as a physical operation is important in chemistry for the separation of materials of different chemical composition.

A solvent is chosen. By dissolving the mixture in the chosen solvent, one component will go into the solution and pass through the filter, while the other will be retained; this is one of the most important techniques used by chemists to purify compounds. Filtration is important and used as one of the unit operations of chemical engineering, it may be combined with other unit operations to process the feed stream, as in the biofilter, a combined filter and biological digestion device. Filtration differs from sieving. In sieving, particles that are too big to pass through the holes of the sieve are retained. In filtration, a multilayer lattice retains those particles that are unable to follow the tortuous channels of the filter. Oversize particles may form a cake layer on top of the filter and may block the filter lattice, preventing the fluid phase from crossing the filter. Commercially, the term filter is applied to membranes where the separation lattice is so thin that the surface becomes the main zone of particle separation though these products might be described as sieves.

Filtration differs from adsorption, where it is not the physical size of particles that causes separation but the effects of surface charge. Some adsorption devices containing activated charcoal and ion exchange resin are commercially called filters, although filtration is not their principal function. Filtration differs from removal of magnetic contaminants from fluids with magnets, because there is no filter medium. Commercial devices called ‘magnetic filters’ are sold, but the name reflects their use, not their mode of operation. In biological filters, oversize particulates are trapped and ingested and the resulting metabolites may be released. For example, in animals, renal filtration removes waste from the blood, in water treatment and sewage treatment, undesirable constituents are removed by absorption into a biological film grown on or in the filter medium, as in slow sand filtration. There are many different methods of filtration. Separation is achieved by some form of interaction between the substance or objects to be removed and the filter.

The substance, to pass through the filter must be a fluid, i.e. a liquid or gas. Methods of filtration vary depending on the location of the targeted material, i.e. whether it is dissolved in the fluid phase or suspended as a solid. There are several filtration techniques depending on the desired outcome namely, hot and vacuum filtration; some of the major purposes of getting the desired outcome are, for the removal of impurities from a mixture or, for the isolation of solids from a mixture. Hot filtration method is used to separate solids from a hot solution; this is done in order to prevent crystal formation in the filter funnel and other apparatuses that comes in contact with the solution. As a result, the apparatus and the solution used are heated in order to prevent the rapid decrease in temperature which in turn, would lead to the crystallization of the solids in the funnel and hinder the filtration process. One of the most important measures to prevent the formation of crystals in the funnel and to undergo effective hot filtration is the use stemless filter funnel.

Due to the absence of stem in the filter funnel, there is a decrease in the surface area of contact between the solution and the stem of the filter funnel, hence preventing re-crystallization of solid in the funnel, adversely affecting filtration process. Cold Filtration method is the use of ice bath in order to cool down the solution to be crystallized rather than leaving it out to cool it down in the room temperature; this technique results to the formation of small crystals as opposed to getting large crystals by cooling the solution down at room temperature. Vacuum Filtration technique is most preferred for small batch of solution in order to dry out small crystals; this method requires a Büchner funnel, filter paper of smaller diameter than the funnel, Büchner flask, rubber tubing to connect to vacuum source. Two main types of filter media are employed in laboratories: a surface filter, a solid sieve which traps the solid particles, with or without the aid of filter paper (e.g. Büchner funnel, Belt filter, Rotary vacu

Konstantinos Bakopoulos

Konstantinos Th. Bakopoulos was a Greek General in the Hellenic Army who took part in the Balkan Wars, played a crucial conciliatory role in Greek military politics during the 1930s and distinguished himself in the fight against the Nazis during World War II. In 1943 he was imprisoned in German concentration camps until the end of the war in 1945. K. Th. Bakopoulos was born in 1889 near Tripoli, Province of Arkadia, his parents and Vassiliki, had fourteen children, of whom Konstantinos was the eleventh. His father Theodoros was mayor of Korythion-Mantinias in the Province of Arkadia, his grandfather Nikolaos had been mayor of the same village. On June 26, 1912, Bakopoulos graduated from the Military Academy as a Second Lieutenant of the Artillery. By the beginning of World War II, he had attained the rank of Lt. General and was given command of the Army Section of Eastern Macedonia — a crucial post for the defense of the Nation. In 1912-3, General Bakopoulos fought in the Balkan Wars. In the mid-1930s, he distinguished himself as an impartial Military Commander of Athens, as follows: after the “1935 officers’ attempted coup d’état” on March 1, he served as ex-officio Presiding Judge at the Court Martial of the leaders accused of organizing the revolt.

Although these officers were found guilty, Bakopoulos was able to contribute to relative unity within the army by resisting heavy political pressure by the monarchists to condemn the accused to death. The monarchists in command disapproved of this act of clemency but, in time, they did recognize the need for peace in the army; those were troubled times. On December 7, 1935 Bakopoulos was appointed Minister and Governor General of the Island of Crete in the government of Konstantinos Demertzis - a position he held until March 14, 1936. In the second government of Demertzis Bakopoulos was appointed Deputy Minister of the Interior on March 23, three weeks before the Prime Minister’s sudden death on April 13, 1936. On that same date Ioannis Metaxas received the mandate from King George to form a new government and on April 16 he received a Vote of Confidence from the Parliament with 241 votes for, 16 against and 4 abstentions. Bacopoulos was appointed Deputy Minister of the Interior in that parliamentary government of Prime Minister I.

Metaxas. However, Metaxas proclaimed a dictatorship on August 4. On August 5, 1936, Bacopoulos left the government, his democratic and conciliatory leadership, as described above and in other politico-military situations, has since been hailed on both sides of the then-highly polarized military/political spectrum of Monarchists vs Republicans. At the beginning of World War II, General Bakopoulos was Commanding Officer of the Eastern Macedonia Army Section. At that time, he was in charge of the so-called Metaxas Line, a series of about 20 forts along the Greek-Bulgarian border, he and his men, against all odds repelled an invading German infantry army during fierce battles that lasted several days, including the now-renowned battle at Fort Rupel. The Germans invaded Greece on April 6, 1941, after the collapse of the Greek resistance east of the Axios River, they entered Greece from Yugoslavia, overrun by Hitler’s army. The attack on the Metaxas Line was launched from Bulgaria and was supported by artillery and bomber aircraft.

Both Greeks and Germans suffered heavy losses. Meanwhile, the German 2nd Panzer Division advanced through Yugoslav territory into Greece, headed East, south of the Metaxas Line defenses and captured Thessaloniki on April 9, thus TSAM was cut off from the mainland. Only did Bakopoulos negotiate an honourable surrender of his troops in order to save his men and prevent the bombing of the vital port city of Thessaloniki; this surrender was decided after Bakopoulos received authorization from General Alexandros Papagos, Head of the High Military Command in Athens. The battle of the Metaxas Line together with other acts of resistance against the Italian attempted invasion and the German occupation are celebrated annually with school parades and Greek media coverage. A characteristic assessment of the battle of the Metaxas Line and Fort Rupel, as well as the role of General Bakopoulos to save his men and to prevent the bombing of Thessaloniki is given by Konstantinos I. Despotopoulos, ex president of the Athens/Greek Academy.

See mention by K. I. Despotopoulos of Bakopoulos’ role in “The refusal of submission”. At 5:30 a.m. July 25, 1943 Bakopoulos was arrested by the Gestapo, along with four other top-ranking Greek generals, for planning and organizing military and civilian resistance to the Nazi occupation, they were deported to various concentration camps in Germany, where they were interned for two years as hostages, until their release by the Fifth U. S. Army at the end of the war. For additional details on Konstantinos Th. Bakopoulos and further insight into Nazi diplomatic and military tactics, consult his book "The Imprisonment of the Five Gen

Reader's Digest National Word Power Challenge

The Reader's Digest National Word Power Challenge was an annual vocabulary competition in the United States for youth in sixth, seventh, or eighth grade. It was sponsored by Reader's Digest magazine. Competition began at school level. Teachers gave students 25-question multiple-choice tests. Classroom winners competed with other classroom winners from the same grade to determine the school-wide grade-level champion; the school champion took a multiple-choice test which determined the top 100 students in the state. The top 100 students were invited to a state competition, where they were given 25 multiple-choice questions to determine the top ten; the top ten went through a few rounds of questions to determine the state champion. The state champion advanced to national competition. Students from every state, Washington, D. C. and one student from a Department of Defense school got to compete at national level. The students took a 25-question multiple-choice test, with the top ten scorers going on to compete in a nationally televised event.

The moderator was a celebrity. All students at the state level received treat bags; the top 10 students at the state level received Reader's Digest books. All students at the national level received treat bags. All state winners were offered free trips to the location of the national competition. Scholarships were awarded at the national level: First place: $25,000 Second place: $15,000 Third place: $10,000 In 2007, the RDNWPC website stated that the competition would not be held for the 2007-2008 year; the Reader's Digest website no longer mentions the RDNWPC. National Vocabulary Championship Scripps National Spelling Bee

Arab Mountain Fire Observation Station

The Arab Mountain Fire Observation Station is a historic fire observation station located on Mount Arab at Piercefield in St. Lawrence County, New York; the station includes a 40-foot-tall, steel frame lookout tower erected in 1918, an observers cabin built about 1948, a trace of the foundation of the original cabin, a structure used as a root cellar in the 1940s, the foot trail. The tower is a prefabricated structure built by the Aermotor Corporation and provided a front line of defense in preserving the Adirondack Forest Preserve from the hazards of forest fires, it was listed on the National Register of Historic Places in 2001. The Fire Towers of New York

Juiced (book)

Juiced: Wild Times, Rampant'Roids, Smash Hits & How Baseball Got Big is a 2005 book by Jose Canseco and his personal account of steroid usage in Major League Baseball. The book is autobiographical, it focuses on Canseco's days as a major leaguer, his marriages, his daughter, off-field incidents including his barroom brawl in 2001; the book deals with anabolic steroids, drawing upon the personal experiences of Canseco. He takes personal credit for introducing steroids to baseball and names former teammates Mark McGwire, Juan González, Rafael Palmeiro, Iván Rodríguez, Jason Giambi as fellow steroid users, he believes he was blackballed by baseball when Bud Selig decided that the league needed to be cleaned up. One of Juiced's central precepts is that steroid use is not in and of itself a bad thing, as long as the person is being monitored by a physician and the dosages are small. Canseco believes that steroids cannot only improve the game of baseball but improve and lengthen lives and that more research needs to be done on the topic.

Canseco claims to discredit many of the myths regarding steroids, asserting that they do not break down a person's body if used and can help a person recover from injuries. During the A&E Network's one-hour documentary, Jose Canseco: The Last Shot, Canseco said he "regrets mentioning players. I never realized this was going to blow up and hurt so many people." Canseco discusses his relationship with Madonna, claiming that she was infatuated with him and that he was never interested in her. Canseco details his opinions on different managers, including Tony La Russa, Joe Torre, Dusty Baker. Canseco claims. MLB wanted him discredited because he was "the godfather of steroids" and could be damaging to the game. Canseco claims that, when he was arrested for domestic violence for fighting with his first wife, the two were arguing while driving on the highway, that he accidentally hit her car. Canseco discusses his life on the road relating to women. Although Canseco accused Roger Clemens of steroid use, he extolls Clemens' apparent marital fidelity, saying that Clemens was "one of the few baseball players I know who never cheated on his wife."

However, reports of an alleged Clemens affair with country singer Mindy McCready surfaced in 2008, followed by allegations of four other extramarital affairs. Canseco says that he met his second wife at a Hooters in Ohio. Canseco claims to have once run a 3.9 second 40-yard dash, which would be the fastest time recorded. Banned substances in baseball Vindicated

Manuel dos Santos (swimmer)

Manuel dos Santos Junior is a former Brazilian swimmer, former world record holder and a bronze medalist in 100-metre freestyle at the Olympic Games in Rome in 1960. At 4 years of age, Manoel spent months in a hospital, recovering from recurrent threats of pneumonia and similar diseases, that his body suffered, his father saw in swimming the salvation of that drama. Before completing eleven years old, in early 1950, Manoel was studying in Rio Claro, in the Gymnasium Koelle, a German college; the boy found himself away from his family, which he saw only on holidays and "holy week", when he took the train to the western state. There in Rio Claro, the rigid routine of the college, Manoel fits well with the swimming program. In a 20-meter pool, under the guidance of Bruno Buch, his first master, he began to train and make the team gym; the strongest swimmer of the group was a boy three years older than Manoel, named João Gonçalves Filho, future champion and South American record holder in the backstroke and an athlete in various sports, who participated in various Olympic Games.

In 1955, Manoel dos Santos approached the national top. He swam backstroke, his training was more focused in this style. In the 100-meter freestyle, Brazil was in a time of transition in national leadership; the top three sprinters in the country at the turn of the decade and early'50s had retired. Paulo Catunda and Haroldo Lara were the fastest at this time. Lara was the best swimmer in the country until 1957, when he retired, moved to Italy and became an opera singer. In March 1955, at age 16, Manoel was summoned to his first international competition, the II Pan American Games in Mexico City. At this time, athletes were still amateurs. In Mexico, after a trip into a military aircraft, a DC-3, which lasted four days, with overnight in Belém, Trinidad and Tobago and Cuba, Manoel competed poorly, his main memory of the tournament was the moment he left desolate of proof, fell on a nearby heating pool and pretending to be loosening up, cried a lot, until the last tear is lost hidden in the middle of chlorine.

At the 1955 Pan American Games in Mexico City, he finished 4th in the 4 × 100-metre medley. The following year, on February 56, in Viña del Mar, was the thirteenth edition of the South American Swimming Championships. At the previous twelve, Brazil defeated Argentina only once, in the same Viña del Mar, in 1941. Manoel dos Santos ranked fifth in the final of the 100-metre freestyle, Haroldo Lara took the fourth position. In the 200-metre backstroke, Manoel was fourth and the race was won by his compatriot João Gonçalves. In the 4x100-metre freestyle relay, the competition had a spectacular end. Peru team was the gold medalist, with a time of 3:59.7, a championship record. A tenth of a second ago, silver medalist, arrived Brazil; the Argentines came in nine-tenths of a second behind Brazil. The Brazilian relay team had Haroldo Lara, Manuel dos Santos, João Gonçalves and Aristarco de Oliveira. In partial takes, Manoel was the fastest of the four, he stated that, at that moment, he realized that his specialty and future were the 100-metre freestyle, the backstroke was just a byproduct.

This flare, this awareness of where his true talent lay resulted in a short time, a leap of improvement. As for the South American, as expected, porteños took the title again. In November 1956, at the new pool of CR Vasco da Gama, Manoel dos Santos failed to get Olympic qualification, by two tenths of a second. In 1957, finishing the secondary school in Rio Claro, Manoel dos Santos moved to São Paulo; the choice of the new city was due to Minoru Hirano, his new coach, a father. Hirano entered to swimming by the paths of the translation service, carried out during the stay of the "Flying Fish" in Brazil in 1950. Hirano got much swimming knowledge and deciphering the Japanese Olympians and world record holders. In the late 50s, the footage of the training in Brazil, began to increase substantially. Hirano was against the current, he did Manoel swim a thousand meters and working leg, positioning stroke, angle etc. chin, finished with a half dozen shots of 25m. He could not attend the training, Manoel came alone to the session with a little paper in hand, or the sequence decorated into his head.

In December 1957, Manoel broke the Brazilian record of Haroldo Lara, the South American record of Argentine Pedro Galvao in Santos, on 25 meter pool, with a time of 56.5. Further, in February 1958, was held the South American Championships in Montevideo. For the first time in the history of the tournament, the winner of the 100-metre freestyle won the race handily, not in the beat of hand, but two and a half seconds ahead of, or fifteen feet away - Manoel dos Santos; the only Brazilian besides Armando Freitas in 1939. The silver medal went to nearly invincible Ismael Martínez Merino, Peruvian three times champion in 52, 54 and 56; the Manoel's time in qualifying, 56.6, represented new South American record, as from 1958, all international federations officiated the rule of consider valid only records obtained in 50 meter pool. The following year, came the first trip to the United States; the beds in the Olympic village assembled at the University of Chicago, were those of American soft mattress and uncomfortable for someone who grew up sleeping on a hard bed of boarding school.

The body aching, slept, back that do not reared more, affected the balance of swimming. Manoel dos Santos, the great hope of the Brazilian Swimming to win a medal at the Pan American Games in 1959, got only a fourth place in the 100-metre freestyle, swimming above the 58s, when expectations revolved around the 56s. T