Acute(急性) and chronic(慢性) toxicity Acute toxicity refers to a rapid and serious response to a high but short-lived dose Acute poisons interfere with essential physiological processes, leading to a variety symptoms of distress, even death Chronic toxicity refers to a time-lagged response to a relatively low but prolonged exposure

Vice President/General Manager Engineering Military Aircraft and Missile Systems Group (retired), The Boeing Company Al Haggerty was vice president and general manager of Engineering for Boeing Military Aircraft and Missile System until March 31st, 2001. He was also the Executive Focal Point for the Lean Enterprise for the unit. Prior to this assignment, he was vice president of Engineering for

Toxic metals Some metals are essential for the normal development and well-being of humans and other creatures They include Na, K, ca, Mg, cu, Cr, and Zn Other metals are toxic even when present in an organism at very low concentrations Examples: Antimony, Arsenic, Barium

pH of a buffer and buffer capacity Example: For a buffer solution consisting of 0. 1 M acetic acid and o1M sodium acetate the ph of the solution is 4.75 HAc= i If an amount of hydrochloric acid equivalent to 10% of the acetate present, is added to the buffer, what is the new pH of the solution?

Unit 1 Famous Universities In this unit, you will first listen, and then talk about famous universities; read about Oxford University and Stanford University; understand both Passage A and Passage B;

Unit 12 Claim and Settlement Points for attention: When making a claim, plan your letter as follows: Begin by regretting the need to complain Mention the date of the order, the date of delivery and the goods complained about

Main idea of the text and devices for developing it Main idea of each part and devices for developing it New words

They are solid, thinner filament structures (6-8 nm, in diameter) composed of a double-helical polymer of the protein actin. And microfilaments play a key role of in virtually all types of contractility and location of cells as well as motility within cells

Air quality and particles Epidemiological(流行病学) evidence associates atmospheric particles with diseases and mortality Particles penetrate the lungs, blocking and irritating aIr passages. Particles themselves could exert toxic effects. ( toxic substances present in the particles [polycyclic Aromatic Hydrocarbons are examples of toxic substances in aerosols.]

This chapter discusses privately owned forests and timber management in a market economy, including : (1) private property rights and tenure (2) landowner objectives (3) landowner characteristics (4) markets (5) government policies impacts