Clerk: According to the Rules of the Senate, the Clerk is elected by the members of the Senate and is tasked with maintaining records of all Senate bills and resolutions. The Clerk is also responsible for handling all documents received from other government departments.
Snare drum
The snare drum or side drum is a percussion instrument. It has strands of "snares" made of curled metal wire, metal cable, plastic cable, or gut cords. They are stretched across the skin on the bottom of the drum. Pipe and tabor and some military snare drums can have a second set of snares on the bottom side of the top head. This is used to make a "brighter" sound. The snare drum is considered one of the most important drums of the drum kit.
The snare drum can make some special sounds:
Economic boom
Economic boom is a phase when the economy has a huge increase. It is a natural cycle.
The United States of America had an essential supply of natural resources such as timber, iron, coal, minerals, oil and land. Immigrants provided a plentiful and cheap work force to utilise these resources. This enabled America to become a huge economic power at the beginning of the 20th century. These resources were an important foundation for the economy.
Whilst European economies suffered during the First World War, the USA experienced significant growth. US banks loaned money to Europe and businesses sold much needed goods. The war also provided a stimulus for inventions in production, materials and advertising. Immediately after the war there was a small slump but from 1922 the USA experienced an unprecedented economic boom.
Electricity developed slowly before the war but during the 1920s the electricity industry experienced a huge boom. By 1929 the majority of houses in America had electricity and 70 per cent of them used it for lighting purposes. As a result of the development of factories to produce consumer goods for the American people, the demand for electricity doubled. Electrical power was introduced in factories to drive machinery, and thus it became possible to introduce mass production to a number of factories, eg refrigerators, washing machines, vacuum cleaners and radio sets.
The car industry is the best example of mass production during the period. Henry Ford was a pioneer with his idea of producing affordable cars for the people of America. He set about realising his dream by producing his early cars in small workshops. He had groups of men working for him and gradually the cars were built.
Henry Ford and his son posing in the model F Ford car in 1905.
Henry Ford and his son posing in the model F Ford car in 1905
Henry Ford's hard work bore fruit. As he produced more and more cars, he could reduce his prices. By 1925 the price of a car was around $290, which was much cheaper than the price of $850 in 1908. Henry Ford was of the opinion that it was better to sell more cars for a small profit, as that meant employing more workers.
By 1929 Americans owned 23 million cars. The workers earned good wages ($5 per day), thousands of jobs were created, roads were built, petrol stations were built, as were hotels and restaurants. Therefore the entire economy was given a substantial boost due to the car industry.
In order to help American people to purchase the new goods that were available, systems of hire-purchase and credit were introduced. This meant that a person could buy something by paying for it on a monthly basis. As a result, the majority of Americans could afford expensive goods. In order to encourage Americans to take advantage of the scheme, advertisements were placed on roadsides, on the radio, in newspapers and in cinemas.
During the same period, chain stores appeared for the first time, eg J P Penney. Catalogue shopping also became fashionable as it was a convenient way of buying goods.Tremors (movie)
Tremors is an American science fiction comedy horror movie. It is set in Nevada and is directed by Ron Underwood. The screenplay was written by S.S. Wilson and Brent Maddock.
Valentine and Earl want to go to Bixby, Nevada and they leave the Perfection Valley. A subterranean animal kills five people. The Perfection Valley is in danger.
Tremor
In biology, a tremor is when antagonist muscles move repeatedly without being controlled. There are different forms of tremors. Very often, a tremor is a symptom for another condition, and not its cause. People with a tremor are not necessarily sick. For example, physiological tremors are measurable, but not visible; they occur in all humans.
Grignard reaction
The Grignard reaction (pronounced ) is an organometallic chemical reaction in which alkyl- or aryl-magnesium halides (Grignard reagents) attack electrophilic carbon atoms that are present within polar bonds (for example, in a carbonyl group as in the example shown below). Grignard reagents act as nucleophiles. The Grignard reaction produces a carbon–carbon bond. It alters hybridization about the reaction center. The Grignard reaction is an important tool in the formation of carbon–carbon bonds. It also can form carbon–phosphorus, carbon–tin, carbon–silicon, carbon–boron and other carbon–heteroatom bonds.
It is a nucleophilic organometallic addition reaction. The high pK value of the alkyl component (pK = ~45) makes the reaction irreversible. Grignard reactions are not ionic. The Grignard reagent exists as an organometallic cluster (in ether).
The disadvantage of Grignard reagents is that they readily react with protic solvents (such as water), or with functional groups with acidic protons, such as alcohols and amines. Atmospheric humidity can alter the yield of making a Grignard reagent from magnesium turnings and an alkyl halide. One of many methods used to exclude water from the reaction atmosphere is to flame-dry the reaction vessel to evaporate all moisture, which is then sealed to prevent moisture from returning. Chemists then use ultrasound to activate the surface of the magnesium so that it consumes any water present. This can allow Grignard reagents to form with less sensitivity to water being present.
Another disadvantage of Grignard reagents is that they do not readily form carbon–carbon bonds by reacting with alkyl halides by an S2 mechanism.
François Auguste Victor Grignard discovered Grignard reactions and reagents. They are named after this French chemist (University of Nancy, France) who was awarded the 1912 Nobel Prize in Chemistry for this work.
The addition of the Grignard reagent to a carbonyl typically proceeds through a six-membered ring transition state.
However, with steric hindered Grignard reagents, the reaction may proceed by single-electron transfer.
Grignard reactions will not work if water is present; water causes the reagent to rapidly decompose. So, most Grignard reactions occur in solvents such as anhydrous diethyl ether or tetrahydrofuran (THF), because the oxygen in these solvents stabilizes the magnesium reagent. The reagent may also react with oxygen present in the atmosphere. This will insert an oxygen atom between the carbon base and the magnesium halide group. Usually, this side-reaction may be limited by the volatile solvent vapors displacing air above the reaction mixture. However, chemists may perform the reactions in nitrogen or argon atmospheres. In small scale reactions, the solvent vapors do not have enough space to protect the magnesium from oxygen.
Grignard reagents are formed by the action of an alkyl or aryl halide on magnesium metal. The reaction is conducted by adding the organic halide to a suspension of magnesium in an ether, which provides ligands required to stabilize the organomagnesium compound. Typical solvents are diethyl ether and tetrahydrofuran. Oxygen and protic solvents such as water or alcohols are not compatible with Grignard reagents. The reaction proceeds through single electron transfer.