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Shenandoah Valley Governor's School
The SVGS logo is a form of the Sierpinski triangle.
Address
, 22939
Information
Type	Magnet school
Established	1993
School district	Augusta County Public Schools
Director	Lee Ann Whitesell
Grades	11-12
Number of students	175
Color(s)	Teal, purple
Website	Shenandoah Valley Governor's School

The Shenandoah Valley Governor's School is one of Virginia's 18 state-initiated magnetGovernor's Schools. It is a part-time school where 11th and 12th grade students take advanced classes in the morning (receiving their remaining classes from their home high school).

Curriculum[edit]

Ozonation of drinking and wastewater relies on ozone (O3) and hydroxyl radical (.OH) as oxidants. Both oxidants react with dissolved organic matter (DOM) and alter its composition, but the selectivity of the two oxidants and mechanisms of reactivity with DOM moieties are largely unknown. The reactions of O3 and.OH with two DOM isolates were studied by varying specific ozone doses (0.1–1. Aims: To assess the association between prenatal exposure to organochlorine compounds and thyroid status in newborns from an area with high levels of hexachlorobenzene (HCB). Methods: A total of 98 mother-infant pairs (83.1% of all children born during the period 1997–99 in a specific area polluted with HCB) were recruited. Levels of organochlorine compounds were measured in 70 cord serum. This review was conducted to describe the microbial reduction of hexavalent chromium Cr(VI) in general and a potential for biological treatment of Cr(VI)-containing wastes in particular. Cr(VI) is the highest oxidation state of the metal chromium, which is widely used in various industries. Chromate (CrO4 −2) is the prevalent species of Cr(VI) in natural aqueous environments and is the. This review was conducted to describe the microbial reduction of hexavalent chromium Cr(VI) in general and a potential for biological treatment of Cr(VI)-containing wastes in particular. Cr(VI) is the highest oxidation state of the metal chromium, which is widely used in various industries. Chromate (CrO4 −2) is the prevalent species of Cr(VI) in natural aqueous environments and is the.

There are two curricula at SVGS:

The tomb raider movie. The curriculum for the Math Science and Technology program includes the following college prep and dual enrollment classes: Research and Engineering, Robotics, Advanced Technology, Astrophysics, AP Computer Science, Pre Calculus, AP Calculus, DE Calculus, DE Discrete Mathematics, AP Statistics, DE Molecular Biology, AP Environmental Science, DE Environmental Chemistry, DE Physics, and Modern Physics.

The curriculum for the Arts and Humanities program includes DE Acting I (through JMU), Acting II, DE Introduction to Theatre (through JMU), Advanced Dramatic Theories and Criticism, advanced art classes, DE Humanities 111/112, DE Communication, DE Psychology, and DE The Humanities in Western Culture (through BRCC).

Contributing schools[edit]

Extracurricular activities[edit]

Electric Vehicle Team
Robotics Team
Network Team
Envirothon Team
Outreach (with elementary and middle schoolers)

External links[edit]

Coordinates: 38°6′55.8″N78°59′20″W / 38.115500°N 78.98889°W

Retrieved from 'https://en.wikipedia.org/w/index.php?title=Shenandoah_Valley_Governor%27s_School&oldid=991246995'

(Redirected from Short-chain chlorinated paraffins)

Structure of 2,3,4,5,6,8-hexachlorodecane, an example of a short-chained chlorinated paraffin (61% Cl by weight)

Structure of 2,5,6,7,8,11,15-heptachloroheptadecane, an example of a medium-chain chlorinated paraffin (52% Cl by weight)

Chlorinated paraffins (CPs) are complex mixtures of polychlorinated n-alkanes. The chlorination degree of CPs can vary between 30 and 70 wt%. CPs are subdivided according to their carbon chain length into short-chain CPs (SCCPs, C_10–13), medium-chain CPs (MCCPs, C_14–17) and long-chain CPs (LCCPs, C_>17). Depending on chain length and chlorine content, CPs are colorless or yellowish liquids or solids.^[1]

Production[edit]

Chlorinated paraffins are synthesized by reaction of chlorine gas with unbranched paraffin fractions (<2 % isoparaffins, <100 ppm aromatics) at a temperature of 80–100 °C.^[2] The radical substitution may be promoted by UV-light.^[3]^[1]

C_xH_(2x+2) + y Cl₂ → C_xH_(2x−y+2)Cl_y + y HCl

When the desired degree of chlorination is achieved, residues of hydrochloric acid and chlorine are blown off with nitrogen. Epoxidized vegetable oil, glycidyl ether or organophosphorous compounds may be added to the final product for improved stability at high temperatures.^[4]^[5]

Commercial products have been classified as substances of unknown or variable composition. CPs are complex mixtures of chlorinated n-alkanes containing thousands of homologues and isomers^[6] which are not completely separated by standard analytical methods.^[7]

CPs are produced in Europe, North America, Australia, Brazil, South Africa and Asia.^[8] In China, where most of the world production capacity is located, 600,000 tons of chlorinated paraffins were produced in 2007.^[9] Production and use volumes of CPs exceeded 1,000,000 tons in 2013.^[10]

Industrial applications[edit]

Production of CPs for industrial use started in the 1930s.^[11] Currently, over 200 CP formulations are in use for a wide range of industrial applications, such as flame retardants and plasticisers, as additives in metal working fluids, in sealants, paints, adhesives, textiles, leather fat and coatings.^[12]^[1]

Safety[edit]

Short-chain CPs are classified as persistent and their physical properties (octanol-water partition coefficient (logK_OW) 4.4–8, depending on the chlorination degree) imply a high potential for bioaccumulation. Furthermore, SCCPs are classified as toxic to aquatic organisms, and carcinogenic to rats and mice. Therefore, it was concluded that SCCPs have PBT and vPvB properties and they were added to the Candidate List of substances of very high concern for Authorisation under REACH Regulation.^[13] SCCPs (average chain length of C₁₂, chlorination degree 60 wt%) were categorised in group 2B as possibly carcinogenic to humans from the International Agency for Research on Cancer (IARC).^[14] In 2017, it was agreed to globally ban SCCPs under the Stockholm Convention on Persistent Organic Pollutants, effective December 2018. However, also MCCPs are toxic to the aquatic environment and persistent; MCCPs in soil, biota, and most of the sediment cores show increasing time trends over the last years to decades; MCCP concentrations in sediment close to local sources exceed toxicity thresholds such as the PNEC.^[10]

References[edit]

^ ^a^b^cRossberg, M.; Lendle, W.; Pfleiderer, G.; Tögel, A.; Dreher, E. L.; Langer, E.; Rassaerts, H.; Kleinschmidt, P.; Strack (20

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