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claireb27

Provide energy from fusion - Engineering Challenges - 0 views

  • n theory, the lithium in that battery could supply your household electricity needs for 15 years.
  • Earthbound reactors cannot achieve the high pressures of the sun’s interior
  • But temperatures much higher than the sun’s can be created to compensate for the lesser pressure,
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  • heavier forms of hydrogen, known as deuterium (with one proton and one neutron) and tritium (one proton plus two neutrons) are fused.
charlottecr

Tox Town - Phthalates - Toxic chemicals and environmental health risks where you live a... - 0 views

  • The human health effects of phthalates are not yet fully known but are being studied by several government agencies, including the Food and Drug Administration, the National Institute of Environmental Health Sciences, and the National Toxicology Program's Center for the Evaluation of Risks to Human Reproduction. 
  • Di(2-ethylhexyl) phthalate is listed as "reasonably anticipated to be a human carcinogen" in the Twelfth Report on Carcinogens published by the National Toxicology Program. 
charlottecr

CDC - NBP - Factsheet - Pthalates - 0 views

  • hthalates are a group of chemicals used to make plastics more flexible and harder to break.
  • Once phthalates enter a person's body, they are converted into breakdown products (metabolites) that pass out quickly in urine.
claireb27

Sustainable nuclear fusion breakthrough raises hopes for ultimate green energy | Scienc... - 0 views

  • generated more energy from fusion reactions than they put into the nuclear fuel,
  • The ultimate goal – to produce more energy than the whole experiment consumes – remains a long way off
  • with zero carbon emissions during operation and minimal waste
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  • 92 powerful lasers to crush a minuscule amount of fuel so hard and fast that it becomes hotter than the sun.
  • The lasers are fired into a gold capsule that holds a 2mm-wide spherical pellet.
  • The fuel is coated on the inside of this plastic pellet in a layer as thin as a human hair.
  • When the laser light enters the gold capsule, it makes the walls of the gold container emit x-rays, which heat the pellet and make it implode with extraordinary ferocity. The fuel, a mixture of hydrogen isotopes called tritium and deuterium, partially fuses under the intense conditions.
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    article on recreating nuclear fusion and its future applications
charlottecr

Antimony (Sb) - Chemical properties, Health and Environmental effects - 0 views

  • Antimony compounds are used to make flame-proofing materials, paints, ceramic enamels, glass and pottery
  • Human exposure to antimony can take place
  • by skin contact
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  • As the exposure continues more serious health effects may occur, such as lung diseases, heart problems, diarrhea, severe vomiting and stomach ulcers.
claireb27

BBC - Future - Fusion: The quest to recreate the Sun's power on Earth - 0 views

  • It works by forcing together two types, or isotopes, of hydrogen
  • Provence in southern France
  • emand is expected to double by 2050, while the share coming from fossil fuels – currently 85%
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  • engineers need to build the reactor to withstand temperatures at least ten times that of the Sun – which means hundreds of millions of degrees.
  • physicists have designed a doughnut-shaped reaction chamber, called a tokamak.
  • okamak deploys a powerful magnetic field to suspend and compress the hydrogen plasma
  • the fusion reaction is not self perpetuating.
  • he reaction far safer.
  • one of the hydrogen isotopes used, tritium, is radioactive
  • moderately seismically active
  • he site won't be ready for the first experiments until 2020.
  • deuterium (a hydrogen isotope abundant in sea water) and tritium (which will be made from lithium), won't take place until 2028.
  • The plan is to use 50 megawatts (in heating the plasma and cooling the reactor), and get 500 MW out.
  • 1997, achieved a 16 MW output with a 25 MW input.
  • If Iter is successful in its proof of principle mission, the first demonstration fusion plants will be built,
  • the technology remains unproven,
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    "The quest to recreate the Sun's power on Earth"
charlottecr

Toluene | Technology Transfer Network Air Toxics Web site | US EPA - 0 views

  • he central nervous system (CNS) is the primary target organ for toluene toxicity in both humans and animals for acute (short-term) and chronic (long-term) exposures.
  • narcosis have been frequently observed in humans acutely exposed to low or moderate levels of toluene by inhalation;
  • Cardiac arrhythmia
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  • Following the ingestion of toluene a person died from a severe depression of the CNS. Constriction and necrosis of myocardial fibers, swollen liver, congestion and hemorrhage of the lungs, and tubular kidney necrosis were also reported.
  • Physical Properties
franklind2015

HowStuffWorks "Nonstick Cookware History" - 0 views

  • searching for a less toxic chemical to use as a new refrigerant.
    • franklind2015
       
      Roy Plunkett tried to produce tetrafluoroethylene and instead produced polytetrafluoroethylene. It was a slippery substance. Patented in 1941. Trademarked by DuPont as Teflon in 1945.
franklind2015

Why do we use microwaves? - 0 views

  • They do not fit through tight spaces and they do not have penetrating power.
  • More things are capable of absorbing microwaves
franklind2015

Science Week - What's the Chemistry of Cooking? - 0 views

  • casein
    • franklind2015
       
      Found in milk and dairy products will affectively wash away capsaicin the chemical that makes things spicy.
charlottecr

NRDC: Learn About Mercury and Its Effects - 0 views

  • ce in the human body, mercury acts as a neurotoxin, interfering with the brain and nervous system.
  • s brain is still developing and rapidly absorbing nutrients. Ev
  • arly hazard
icam45

HowStuffWorks "How Plastics Work" - 0 views

  • They're large molecules called polymers, which are composed of repeating units of shorter carbon-containing compounds called monomers
  • Most plastic is chemically
  • it doesn't decay. Therefore, plastic disposal poses a difficult and significant environmental problem
marthamck

How Drugs are Developed and Approved - 0 views

  • sure that drugs marketed in this country are safe and effective. CDER does not test drugs, although the Center's Office of Testing and Research does conduct limited research in the areas of drug quality, safety, and effectiveness.CDER is the largest of FDA's five centers.   It has responsibility for both prescription and nonprescription or over-the-counter (OTC) drugs. For more information on CDER activities, including performance of drug reviews,  post-marketing risk assessment, and other highlights, please see the CDER Update: Improving Public Health Through Human Drugs1 The other four FDA centers have responsibility for medical and radiological devices, food, and cosmetics, biologics, and veterinary drugs. Some companies submit a new drug application (NDA) to introduce a new drug product into the U.S. Market.  It is the responsibility of the company seeking to market a drug to test it and submit evidence that it is safe and effective. A team of CDER physicians, statisticians, chemists, pharmacologists, and other scientists reviews the sponsor's NDA containing the data and proposed labeling2. 
charlottecr

Human Health and Lead, Addressing Lead at Superfund Sites | Superfund | US EPA - 0 views

  • In children, lead poisoning can cause: damage to the brain and nervous system behavioral problems anemia liver and kidney damage hearing loss hyperactivity developmental delays in extreme cases, death Although the effects of lead exposure are a potential concern for all humans, young children (less than seven years old) are most at risk (Reagan and Silbergeld, 1989). This increased vulnerability results from a combination of the following factors:
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    effects and symptoms of Lead
charlottecr

Effects of Lead - 0 views

  • Children Even low levels of lead in the blood of children can result in: Behavior and learning problems Lower IQ and Hyperactivity Slowed growth Hearing Problems Anemia In rare cases, ingestion of lead can cause seizures, coma and even death.
nkuzio

Neurons, Synapses, Action Potentials, and Neurotransmission - The Mind Project - 0 views

  •  
    animation of neurotransmission process
chasefortier

Course Information Technology: How MRI Changed the World - 0 views

  • MRI, has improved findings of malignant diseases and saved thousands of lives.
  • It has made early diagnosing of certain diseases possible.
  • especially useful in neurological (brain), musculoskeletal, cardiovascular, and oncological (cancer) imaging.
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  • Damadian's invention came from his observations that the tissue in a cancerous tumor looked differently than healthy tissue, after both tissue samples had been exposed to nuclear magnetic resonance.
  • first MRI examination was performed on July 3, 1977
  • first commercially available MRI was sold in 1980
  • MRI was originally a technique that was referred to as nuclear magnetic resonance imaging (NMRI). However, because the word nuclear was associated in the public mind with ionizing radiation exposure, it is generally now referred to simply as MRI.
  • In a recent study that compared radiography and MRI, MRI demonstrated significantly more erosions than radiography.” (Mak & Hunter, 2009).  MRI has particular advantages in that it is non-invasive, using non-ionizing radiation, and has a high soft-tissue resolution and discrimination in any imaging plane. It may also provide both morphological and functional information.
  • Without this ability, it would be a challenge for physicians to diagnose the correct illness. Instead, to understand what exactly is going on inside the patient, the physicians might have to surgically open the patient.
  • MRI scans have provided valuable images, two dimensional and three dimensional, that aid physicians when they diagnose diseases or problems.
nkuzio

Chemical synapse - Knowledge Encyclopedia - 0 views

  • The adult human brain is estimated to contain from 1014 to 5 × 1014 (100–500 trillion) synapses. Every cubic millimeter of cerebral cortex contains roughly a billion of them.
nkuzio

Neurotransmitters - Chemistry Encyclopedia - structure, proteins, molecule, General Mec... - 0 views

  • Neurotransmitters are formed in a presynaptic neuron and stored in small membrane-bound sacks, called vesicles , inside this neuron. When this neuron is activated, these intracellular vesicles fuse with the cell membrane and release their contents into the synapse, a process called exocytosis.
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