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mede √5/4 o ponto E está em 
é bissetriz do ângulo BÂE. Nessas condições, o segmento 
mede 
C6H4O2(aq) + 2 H2O(
)) + 1/2 O (g) → H2O2 (aq) ΔHº= + 95 kJ .mol-1
H2O() → 1/2 O2(g) + H2 (g) ΔHº= + 286 kJ .mol-1
Fonte: http://www2.uol.com.br/niquel/bau.shtml. Acessado em 25/08/2009.
Os animais que consomem as folhas de um livro alimentam-se da celulose contida no papel. Em uma planta, a
celulose é encontrada
Fonte: http://www.cetesb.sp.gov.br. Acessado em 20/06/2009.
Em algumas cidades, pode-se observar no horizonte, em certos dias, a olho nu, uma camada de cor marrom. Essa condição afeta a saúde, principalmente, de crianças e de idosos, provocando, entre outras, doenças respiratórias e cardiovasculares.
http://tempoagora.uol.com.br/noticias.
Acessado em 20/06/2009. Adaptado.
As figuras e o texto acima referem-se a um processo de
formação de um fenômeno climático que ocorre, por
exemplo, na cidade de São Paulo. Trata-se de
The perils of counterfeit drugs go way beyond being ripped off by dubious online pill-pushers. The World Health Organization (WHO) estimates that 50 per cent of all medicines sold online are worthless counterfeits. In developing nations fake pills may account for as much as 30 per cent of all drugs on the market. Even in the developed world, 1 per cent of medicines bought over the counter are fakes.
Some key events illustrate the risk these pose. In Nigeria, 2500 children died in 1995 after receiving fake meningitis vaccines. In Haiti, Bangladesh and Nigeria, around 400 people died in 1998 after being given paracetamol that had been prepared with diethylene glycol – a solvent used in wallpaper stripper. The fakers are nothing if not market-aware: in the face of an outbreak of H5N1 bird flu in 2005, they began offering fake Tamiflu.
What can be done? The WHO coordinates an umbrella body called the International Medical Products Anti-Counterfeiting Taskforce (IMPACT), an industry initiative that issues alerts when it finds anomalies in the medicine supply chain. Such events include sudden drops in wholesale prices, hinting at fakes coming onto the market, or the mimicking of anti-counterfeiting features on packaging, such as holograms or barcodes, says Nimo Ahmed, head of intelligence at the UK’s Medicine and Healthcare Products Regulatory Agency.
New Scientist, 10 July 2010, p. 18. Adaptado.
Em um funil de separação, encontram-se, em contato, volumes iguais de duas soluções: uma solução aquosa de I2, de concentração 0,1 x 10-3 mol/L, e uma solução de I2 em CCl4, de concentração 1,0 x 10-3 moI/L.
Considere que o valor da constante Kc do equilíbrio
é igual a 100, à temperatura do experimento, para concentrações expressas em moI/L.
Assim sendo, o que é correto afirmar a respeito do
sistema descrito?
The Impact of the Gulf Oil Spill on the U.S.
www.freewebs.com/mathewstolte/oilspills.html. 21/06/2010
Although the oil has been pouring into the Gulf of Mexico for months, the consequences of this larger than ever environmental disaster have yet to be fully examined and determined. Scientists and researchers have started to put together some of the puzzle pieces, and the impact of the Deepwater Horizon oil spill are likely to be big.
North Americans will have fewer choices on the store shelves. The Gulf of Mexico is a huge shipping lane through which products of all shapes and sizes come into North America. From toys to clothes to cars to building materials, you may find that the selection at your local store begins to shrink as shipping lanes slow down as a result of the oil spill.
Whether you’re taking a vacation or hoping to walk along the shore, you may be disappointed. Many beaches in the U.S.A. are now closing as clean-up efforts on removing oil slick from the sands. But the impact may be felt for quite some time as oil continues to wash up on shore.
Many wildlife animals will be impacted by the oil spill. Oiled birds, otter, bald eagles, pelicans, turtles, fish, and dolphins are already washing up on shore, making the beach sights less than palatable for someone looking to see some pristine nature.
Over time, molluscs like clams incorporate calcium into their shells throughout their lifetimes. But the heavy metals like nickel and vanadium from the petroleum industry and the resulting oil spill may be incorporated into the shells of these creatures. As other wildlife consumes these clams, they incorporate the toxins into their bodies, and on it goes as the heavy metals bio-accumulate in the food chain. This could have serious, long-term consequences for human health.
Environmentalists have been working on restoring the populations of oysters by reseeding certain reefs to boost their numbers. The Gulf of Mexico has been home-working on some of these projects, but with the massive oil spilling into that environment, the oysters could soon become tainted with chemicals, making them unsafe to eat.
The Gulf of Mexico is also a nursery for species like shrimp that grow up in the estuaries. The oil that is taking over this natural environment will choke out the plants that make the estuaries so nutritious to shrimp.
According to the National Weather Service, a hurricane like Hurricane Katrina could have a devastating impact on New Orleans. Researchers expect 15 named storms to develop into 8 hurricanes, and with a well-placed hurricane, the oil could be pushed onto New Orleans shores, further impacting the already devastated region.
Adapted from http://www.thenewecologist.com (21/06/2010)
The Impact of the Gulf Oil Spill on the U.S.
www.freewebs.com/mathewstolte/oilspills.html. 21/06/2010
Although the oil has been pouring into the Gulf of Mexico for months, the consequences of this larger than ever environmental disaster have yet to be fully examined and determined. Scientists and researchers have started to put together some of the puzzle pieces, and the impact of the Deepwater Horizon oil spill are likely to be big.
North Americans will have fewer choices on the store shelves. The Gulf of Mexico is a huge shipping lane through which products of all shapes and sizes come into North America. From toys to clothes to cars to building materials, you may find that the selection at your local store begins to shrink as shipping lanes slow down as a result of the oil spill.
Whether you’re taking a vacation or hoping to walk along the shore, you may be disappointed. Many beaches in the U.S.A. are now closing as clean-up efforts on removing oil slick from the sands. But the impact may be felt for quite some time as oil continues to wash up on shore.
Many wildlife animals will be impacted by the oil spill. Oiled birds, otter, bald eagles, pelicans, turtles, fish, and dolphins are already washing up on shore, making the beach sights less than palatable for someone looking to see some pristine nature.
Over time, molluscs like clams incorporate calcium into their shells throughout their lifetimes. But the heavy metals like nickel and vanadium from the petroleum industry and the resulting oil spill may be incorporated into the shells of these creatures. As other wildlife consumes these clams, they incorporate the toxins into their bodies, and on it goes as the heavy metals bio-accumulate in the food chain. This could have serious, long-term consequences for human health.
Environmentalists have been working on restoring the populations of oysters by reseeding certain reefs to boost their numbers. The Gulf of Mexico has been home-working on some of these projects, but with the massive oil spilling into that environment, the oysters could soon become tainted with chemicals, making them unsafe to eat.
The Gulf of Mexico is also a nursery for species like shrimp that grow up in the estuaries. The oil that is taking over this natural environment will choke out the plants that make the estuaries so nutritious to shrimp.
According to the National Weather Service, a hurricane like Hurricane Katrina could have a devastating impact on New Orleans. Researchers expect 15 named storms to develop into 8 hurricanes, and with a well-placed hurricane, the oil could be pushed onto New Orleans shores, further impacting the already devastated region.
Adapted from http://www.thenewecologist.com (21/06/2010)
Irã anuncia a construção de mais reatores nucleares
Mesmo sob sanções impostas pelo Conselho de Segurança da Organização das Nações Unidas (ONU), o Irã anunciou nesta quarta-feira (16) que irá construir mais uma série de reatores nucleares (...). Segundo as fontes iranianas os “poderosos reatores” serão utilizados em usinas destinadas à produção de medicamentos.
O anúncio foi feito uma semana depois de o Conselho de Segurança da ONU impor uma série de sanções ao Irã. No entanto, o diretor-geral da organização de energia nuclear iraniana afirmou que o país “dispõe de mais de 50 anos de experiência em ciência e tecnologia nuclear” que deve ser aproveitada.
Fonte: Agência Brasil, 16/6/2010 – Texto adaptado
