光化学

光化学，研究物质因受光的影响而产生化学效应的一个学科。光催化：研究物质因受光的影响而产生催化效应的一个学科。如TiO2是最常用的光催化剂，它无毒、价廉、抗腐蚀并具有较高的催化活性。 Category:化学 ja:光化学 th:เคมีแสง

催化

催化是利用催化剂加快化学反应速度的方式，许多化学工业要利用催化作用来获得需要的反应速度。因此催化也是一种化工单元过程，催化剂本身在反应中不会被消耗，但催化剂的存在会使反应速度迅速加快，许多种在没有催化剂存在的情况下由于反应速度太慢而基本不可能发生的反应，由于有了催化剂而能迅速反应，从而获得所需要的产品。催化剂可以是各种物质，在无机物反应中，通常是利用酸、碱、或金属或金属化合物作为催化剂，在有机物反应中多是利用有强烈选择性的蛋白质分子作为催化剂，这种催化剂叫做酶，生物体内许多种生物化学反应都是依靠酶进行催化实施的。催化反应可以发生在单相中，也可以发生在多相中：
- 单相催化反应：在单相反应中，催化剂和发生反应的物质都是处于同一相中，一般都是发生在液体状态中，例如以Δ代表催化剂，反应过程如同下列：

\left(\Alpha\right) + \left(\Delta\right) = \left(\Alpha\Delta \right)

\left(\Alpha\Delta \right) + \left(\Beta\right) = \left(\Kappa\right) + \left(\Delta\right)

所以最终结果为：

\left(\Alpha\right) + \left(\Beta\right) + \left(\Delta\right) = \left(\Kappa\right) + \left(\Delta\right)

本来A和B之间不能直接反应或反应速度太慢，Δ的存在促进了A和B之间的反应，生成了新的产品K。
- 多相催化反应：多相反应中催化剂一般是固体，催化反应按照下列步骤进行： #反应物扩散到催化剂的表面； #反应物被吸附到催化剂表面； #被吸附的反应物在催化剂表面解离各键，并因此发生反应，生成新产物； #新的产物从催化剂表面解吸。催化剂的催化作用机理较复杂，不同的催化剂的作用机理不尽相同，酶的催化作用更为复杂，而且具有高度的选择性，只能对某种特定的反应进行催化，在食品工业和药物合成中，经常利用酶来进行催化。 Category:化学工程 Category:化学工业 Category:化学

New Bern (NC)

New Bern is a city located in Craven County, North Carolina where the Trent River and the Neuse River converge, 87 miles (140 km) northeast of Wilmington. In 1900, 9,090 people lived in New Bern, North Carolina; in 1910, 9,961; in 1920, 12,198; and in 1940, 11,815. As of the 2000 census, the city had a total population of 23,128. It is the county seat of Craven County.

History

New Bern was founded by the Swiss in 1710 under the leadership of Christoph von Graffenried, and is named after the capital of Switzerland, Bern. The first permanent seat of the colonial government of North Carolina was located in New Bern. Following the American Revolutionary War, Tryon Palace, former home of British governor William Tryon, became the original Capitol of newly-independent state North Carolina, as it remained until the 1790s. New Bern was the site of a battle early in the American Civil War in which it was captured and occupied by union forces. New Bern is also known as the birthplace of Pepsi Cola, which was invented by New Bern pharmacist Caleb Bradham.yo new bern

Geography

Caleb Bradham New Bern is located at 35°6'33" North, 77°4'9" West (35.109070, -77.069111). According to the United States Census Bureau, the city has a total area of 69.9 km² (27.0 mi²). 66.9 km² (25.8 mi²) of it is land and 3.0 km² (1.2 mi²) of it is water. The total area is 4.30% water.

Demographics

As of the census of 2000, there are 23,128 people, 10,006 households, and 6,183 families residing in the city. The population density is 345.7/km² (895.5/mi²). There are 11,094 housing units at an average density of 165.8/km² (429.5/mi²). The racial makeup of the city is 55.96% White, 40.32% African American, 0.32% Native American, 0.64% Asian, 0.04% Pacific Islander, 1.44% from other races, and 1.28% from two or more races. 2.99% of the population are Hispanic or Latino of any race. There are 10,006 households out of which 27.3% have children under the age of 18 living with them, 40.5% are married couples living together, 18.2% have a female householder with no husband present, and 38.2% are non-families. 33.4% of all households are made up of individuals and 13.2% have someone living alone who is 65 years of age or older. The average household size is 2.26 and the average family size is 2.85. In the city the population is spread out with 23.9% under the age of 18, 8.3% from 18 to 24, 27.0% from 25 to 44, 22.8% from 45 to 64, and 17.9% who are 65 years of age or older. The median age is 39 years. For every 100 females there are 83.8 males. For every 100 females age 18 and over, there are 79.6 males. The median income for a household in the city is $29,139, and the median income for a family is $38,990. Males have a median income of $28,720 versus $21,687 for females. The per capita income for the city is $18,499. 19.4% of the population and 14.7% of families are below the poverty line. Out of the total population, 29.4% of those under the age of 18 and 14.1% of those 65 and older are living below the poverty line.

External links

- [http://www.ci.new-bern.nc.us/ Official web site of New Bern, NC]
- [http://www.newbernchamber.com/ New Bern Area Chamber of Commerce]
- [http://www.visitnewbern.com/ Craven County Convention and Visitor's Bureau]
- [http://docsouth.unc.edu/nc/graffenried/menu.html Christoph von Graffenried's account of the founding of New Bern] Category:Cities in North Carolina Category:Craven County, North Carolina

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