click links in text for more info
SUMMARY / RELATED TOPICS

Isothermal process

An isothermal process is a change of a system, in which the temperature remains constant: ΔT =0. This occurs when a system is in contact with an outside thermal reservoir, the change in the system will occur enough to allow the system to continue to adjust to the temperature of the reservoir through heat exchange. In contrast, an adiabatic process is. In other words, in an isothermal process, the value ΔT = 0 and therefore the change in internal energy ΔU = 0 but Q ≠ 0, while in an adiabatic process, ΔT ≠ 0 but Q = 0. We can say that in isothermal processes T = constant Δ T = 0 d T = 0 while in adiabatic processes Q = 0. Isothermal processes can occur in any kind of system that has some means of regulating the temperature, including structured machines, living cells; some parts of the cycles of some heat engines are carried out isothermally. In the thermodynamic analysis of chemical reactions, it is usual to first analyze what happens under isothermal conditions and consider the effect of temperature.

Phase changes, such as melting or evaporation, are isothermal processes when, as is the case, they occur at constant pressure. Isothermal processes are used and a starting point in analyzing more complex, non-isothermal processes. Isothermal processes are of special interest for ideal gases; this is a consequence of Joule's second law which states that the internal energy of a fixed amount of an ideal gas depends only on its temperature. Thus, in an isothermal process the internal energy of an ideal gas is constant; this is a result of the fact. Note that this is true only for ideal gases. In the isothermal compression of a gas there is work done on the system to decrease the volume and increase the pressure. Doing work on the gas increases the internal energy and will tend to increase the temperature. To maintain the constant temperature energy must leave the system as heat and enter the environment. If the gas is ideal, the amount of energy entering the environment is equal to the work done on the gas, because internal energy does not change.

For isothermal expansion, the energy supplied to the system does work on the surroundings. In either case, with the aid of a suitable linkage the change in gas volume can perform useful mechanical work. For details of the calculations, see calculation of work. For an adiabatic process, in which no heat flows into or out of the gas because its container is well insulated, Q = 0. If there is no work done, i.e. a free expansion, there is no change in internal energy. For an ideal gas, this means that the process is isothermal. Thus, specifying that a process is isothermal is not sufficient to specify a unique process. For the special case of a gas to which Boyle's law applies, the product pV is a constant if the gas is kept at isothermal conditions; the value of the constant is nRT, where n is the number of moles of gas present and R is the ideal gas constant. In other words, the ideal gas law pV = nRT applies. Therefore: p = n R T V = constant V holds; the family of curves generated by this equation is shown in the graph in Figure 1.

Each curve is called an isotherm. Such graphs are termed indicator diagrams and were first used by James Watt and others to monitor the efficiency of engines; the temperature corresponding to each curve in the figure increases from the lower left to the upper right. Log In thermodynamics, the reversible work involved when a gas changes from state A to state B is W A → B = − ∫ V A V B p d V For an isothermal, reversible process, this integral equals the area under the relevant pressure-volume isotherm, is indicated in purple in Figure 2 for an ideal gas. Again, p = nRT/V applies and with T being constant, the expression for work becomes: W A → B = − ∫ V A V B p d V = − ∫ V A V B n R T V d V = − n R T ∫ V A V B 1 V d V = − n R T ln ⁡ V B V A By convention, work is defined as the work on the system by its surroundings. If, for example, the system is compressed the work is positive and the internal energy of the system increases. Conversely, if the system expands, it does work on the surroundings and the internal energy of the system decreases.

It is worth

Al-Mu'addal

Al-Mu'addal ibn Ali ibn al-Layth was the Saffarid ruler of Zarang for a part of 911. In 890 al-Mu'addal and his brother al-Layth helped their father'Ali escape from imprisonment at the hands of the latter's uncle, the Saffarid amir Amr ibn al-Layth; the three of them fled to Khurasan. After'Ali died in 893, the brothers continued to serve Rafi'. In 896 they were captured by'Amr. Near the end of 908 al-Layth made a bid for power against'Amr's son and successor Tahir by occupying part of Zarang. Al-Mu'addal, taken hostage by Tahir, was released in early 909 after Tahir was unable to dislodge al-Layth in an attempt to induce the latter to give up his struggle. Al-Layth maintained his position and Tahir was forced to withdraw. Al-Layth was now amir. In the east, supporters of Tahir were causing unrest in Zabulistan, while in the west, the Turkish general Sebük-eri had transferred his allegiance from the Saffarids to the Abbasid caliph, resulting in the loss of Fars and Kerman. Al-Mu'addal was sent to restore order to Zabulistan.

He moved on to Ghazna and killed a local leader there, but soon encountered stiff resistance and al-Layth was required to send him reinforcements. Despite this, he returned to Sistan near the end of 909 having established the authority of al-Layth in the eastern provinces. In 910 al-Mu'addal participated in al-Layth's campaign against Sebük-eri. Sebük-eri soon after managed to defeat and capture al-Layth, al-Mu'addal was forced to flee to Kerman, where he took control of the local treasury before moving on to Sistan. In Zarang, news of al-Layth's fall caused the people to recognize another brother, Muhammad, as amir. In an effort to cement his power, Muhammad imprisoned al-Mu'addal. Muhammad was subsequently forced to conduct a campaign against the Samanids to the north. After suffering a setback and being forced to end the campaign, his advisors convinced him that he needed al-Mu'addal's support, so he set him free. Al-Mu'addal, seized Zarang, forcing Muhammad to go to Bust instead. Soon afterwards the Samanid Ahmad ibn Isma'il sent an army to take Zarang from the Saffarids.

The Samanids initiated a siege. During the siege al-Mu'addal was informed of Ahmad's taking of Bust and his capture of Muhammad; this prompted him to negotiate with the Samanids, at the end of July 911 he surrendered. Al-Mu'addal's fate was better than that of his predecessors', imprisoned in Baghdad, his surrender allowed the Samanids to take control of Sistan. Bosworth, C. E; the History of the Saffarids of Sistan and the Maliks of Nimruz. Costa Mesa, California: Mazda Publishers, 1994

2014 Oddset Hockey Games

The 2014 Oddset Hockey Games is played between 1–4 May 2014. The Czech Republic, Finland and Russia play a round-robin for a total of three games per team and six games in total. Five of the matches are played in the Ericsson Globe in Stockholm and one match in the Hartwall Arena in Helsinki, Finland. Finland won the tournament for the fifth time; the tournament is a part of the 2013–14 Euro Hockey Tour. All times are local. Best Goaltender: Pekka Rinne Best Defenceman: Juuso Hietanen Best Forward: Oscar Möller Goaltender: Pekka Rinne Defence: Anton Belov, Juuso Hietanen Forwards: Petri Kontiola, Oscar Möller, Viktor Tikhonov MVP: Pekka Rinne

Picture (album)

Picture is the debut album by British progressive rock band Kino. "Losers Day Parade" – 9:04 "Letting Go" – 5:26 "Leave A Light On" – 6:17 "Swimming in Women" – 5:23 "People" – 6:08 "All You See" – 5:08 "Perfect Tense" – 4:16 "Room For Two" – 3:44 "Holding On" – 7:09 "Picture" – 2:23 John Mitchell: lead vocals, guitars Pete Trewavas: bass, bass pedals, backing vocals John Beck: synthesizers, backing vocals Chris Maitland: drums and percussion, backing vocals InsideOut.de – InsideOut Records

Elmer A. Morse

Elmer Addison Morse was a U. S. Representative from Wisconsin. Born in Franksville, Morse attended the common schools of Racine County, he graduated from Ripon College, Wisconsin, in 1893. Morse was elected county superintendent of schools of Racine County in 1893 and reelected in 1895, he attended the law school of the University of Wisconsin–Madison. He commenced practice in Antigo, Wisconsin, he engaged in the insurance and real estate business from 1900 until his death. Morse was elected as a Republican to the Sixtieth, Sixty-first, Sixty-second Congresses, he represented Wisconsin's 10th congressional district. He was an unsuccessful candidate for reelection in 1912 to the Sixty-third Congress, he resumed the practice of law in Wisconsin. He served as delegate to the Republican State conventions in 1934 and 1940, he died in Rochester, Minnesota, on October 4, 1945. He was interred in Elmwood Cemetery, Wisconsin. United States Congress. "Elmer A. Morse". Biographical Directory of the United States Congress.

Elmer Addison Morse at Find a Grave Works by or about Elmer A. Morse at Internet Archive

Pilkington XXX F.C.

Pilkington XXX Football Club was a football club based in Birmingham, England. They joined the Midland Combination Division Three in 1998. In 2002, they changed their name from Burman Hi-Ton, they resigned from the Midland League Division One at the end of the 2015-16 season. It is unclear when the club was formed – the club itself notes that the present name was adopted in 2002 but does not state when the earlier incarnation had been formed, it is known that the club, under its previous name of Burman Hi-Ton F. C. won the Birmingham Works League Division One in the 1996–97 season and joined the Midland Combination in 1998, where the team won the Division Three championship at the first attempt. In 2001–02 the team won the Division Two title to gain promotion to Division One, whereupon the club adopted its present name. Success again came in Division One, with a runners-up spot in 2003–04 gaining the team promotion to the Premier Division. Best league performance: 5th in Midland Combination Premier Division, 2006–07 Best FA Cup performance: First Qualifying Round 2010–11 Best FA Vase performance: Second Round Proper, 2008–09 History page of official club website Pilkington XXX at the Football Club History Database Burman Hi-Ton at the Football Club History Database Pilkington XXX Football Club