Tungsten In the World Of Light Bulbs

Tungsten is a metallic chemical element classified among the transition metals of the periodic table of elements. In continental Europe, the chemical is often referred to by the alternative name of wolfram. That’s why its chemical symbol is W and not T or Tu. The element is well known for its strength and durability, which make it extremely useful in a wide range of industrial applications.

History
People have known about the existence of tungsten since at least the early 1700s, when observers noted that the metal interacted with tin. It was identified as a new element in 1781, and first isolated as a metal in 1783. Its important ores include wolfram and sheltie. In 1784, the de Elhuyar brothers managed to isolate it in Spain, using tungstic acid extracted from wolframite.

Production
The chemical is alloyed with steel to form tough metals that are stable at high temperatures. The worlds tungsten resources are scattered, many different countries control various amounts of it be- cause of how much is in their land. Western Europe controls 30% of the worlds total resources. North America and China both control 25%. Japan controls about 13% and the remaining resources are in smaller countries with only small mines.

Properties
This element is not found in a pure form in nature. If contaminated with other materials, tungsten becomes brittle and difficult to work with. It has the highest melting point and lowest vapor pressure of all metals. It also has excellent corrosion resistance and is not attacked easily by most mineral acids, so it is used a lot for glass-to-metal seals.

It forms compounds with calcium and magnesium that have phosphorescent properties and are used in fluorescent light bulbs. Tungsten carbide (WC) is an extremely hard compound. It is used in the tips of drill bits, high speed cutting tools and in mining machinery. Tungsten hexacarbonyl (also called tungsten carbonyl) is the chemical compound with the formula W(CO)6. This colorless compound, like its chromium and molybdenum analogs, is noteworthy as a volatile, air-stable derivative of tungsten in its zero oxidation state.

Uses
While tungsten tools can be expensive, many workers like them because of their durability and long lifetimes. One of the most famous uses of tungsten is as a filament in light bulbs. Tungsten is also used as a target for X-ray production, as heating elements in electric furnaces and for parts of spacecraft and missiles which must withstand high temperatures. Many structural metal alloys incorporate tungsten since the metal has an extremely high melting point, and the element is also used to make wear-resistant tools.

Molybdenum In Stainless & Alloy Steel

Molybdenum is an essential trace element for virtually all life forms. In industry, it ia applied in many vital fields. In human body, it functions as a cofactor for a number of enzymes that catalyze important chemical transformations in the global carbon, nitrogen, and sulfur cycles.

Description
Discovered in 1778 by Swedish Chemist Carl Wilhelm Scheele and isolated in 1781 by Peter Jacob Hjelm, molybdenum is used mainly as a component of alloyed steel. Because of its softness, color, and greasy feel, it was originally mistaken as a lead compound. A silvery white metal with an atomic number of 42, it is solid at room temperature, has an atomic mass of 95.94, and appears in the periodic table of elements under the chemical symbol of “Mo.” In fact, compared to other pure elements, it has one of the highest melting points. One most unique and therefore useful qualities is its extremely high melting point: 4753 degrees F (2623 degrees C, or 2896 K).

Uses
The most significant of the uses is as an additive in steel and iron alloys. Because of its ability to withstand extremely high temperatures, it is used in the manufacture of missiles, aircrafts, spacecrafts, rifle barrels, light bulb filaments, and furnace components. In the early 21st century, about half of all mined molybdenum was used for iron and steel alloys in construction, tools, auto parts and steam turbines.

One of the important energy-related uses of molybdenum is as a catalyst in the refining of fuel. It can be used as a chemical catalyst. Its versatile chemical structure and the ease with which it transitions between oxidation states makes it an attractive catalyst for scientists creating chemical reactions and syntheses in laboratories.

Production
The chemical can be mined directly, gleaned from ore sources such as molybdenite or molybdenum sulfide (MoS2), obtained as a by-product of copper mining, and recovered from the mineral wulfenite (PbMoO4). Molybdenum hexacarbonyl (also called molybdenum carbonyl) is the chemical compound with the formula Mo(CO)6. The United States is a significant source of Mo in the world, drawing from mines in Colorado, New Mexico, and Idaho. Other prolific producers worldwide include China, Canada, Peru, and Russia.

In Life
As an essential trace element in plants, animals and humans, the element plays an important role in the conversion of atmospheric nitrogen to ammonia. That fact makes the use in fertilizers a common occurrence. Trace amounts of dietary molybdenum is also necessary to promote growth in animals; excessive amounts however is toxic.

Perfluorodecalin: Uses & Global Warming

Perfluorodecalin (C10F18, henceforth PFD) has anumber of medical applications stemming from its use in first-generation perfluorocarbon (PFC)-based blood substitutes. However, the 100-year GWP, used within the Kyoto Protocol, is insensitive to gross uncertainties in the lifetime of PFD.

PFD exists in two isomers: cis- and trans-PFD. The spectrum of trans-PFD was derived by subtraction of the cis-PFD features from a spectrum of the mixed isomers. The spectra were obtained by expanding calibrated volumes into the chamber. The gas sample was flushed into the chamber using air diluent; the use of a gas spreader in the chamber assured turbulent mixing.

Some studies have shown that formulas that include Perflurodecalin improve the skin’s barrier function resulting in increased moisturizing efficacy. However, there are no studies to prove that added oxygen can actually repair wrinkled skin or prevent lines from forming. Conversely, too much oxygen can enhance the number of unstable oxygen molecules which cause free radical damage.

Perfluorodecalin is a fluorocarbon and derivative of decalin, and used in cosmetics and beauty products as to dissolve and deliver oxygen to the skin in formulas (Wikipedia). It is also used as a skin conditioning agent, detangler, and solvent in some formulas. Its ability to dissolve oxygen is thought to revitalize skin and reduce wrinkles, increasing the partial pressure of oxygen (pO2), according to research.

The GWP is calculated using the same method and absolute GWP for CO2 as given in IPCC (2001). A radiative efficiency of 0.56Wm2 ppbv1 and a lifetime of 1000 years, yield GWPs of 5100, 7200 and 9200 relative to CO2 at time horizons of 20, 100 and 500
years, respectively. Because the GWP is reported on a per mass basis, and Perfluorodecalin has alarge molecular weight, its GWP is slightly weaker than many other PFCs, despite its large radiative efficiency. Nevertheless, its GWP remains comparable to the IPCC(2001) 100-year GWP for CF4 of 5700.

The Cosmetic Database rates Perfluorodecalin (CAS No. 306-94-5)as a low hazard and notes only organ toxicity at high doses unlikely to be present in cosmetic formulas. No other studies were found that showed adverse side effects to Perfluorodecalin. It is reproted that, for what we believe is the first time, the infrared absorption cross-sections, radiative efficiency, GWP and atmospheric abundances of PFD.

Although, at current concentrations, PFD makes a trivial contribution to climate change, the principal motivation for this study is that potential future uses might lead to significantly higher releases. For a balanced assessment of the desirability of these uses, it is important that values of the GWP are available.

Mercury Posoning To Huamnbeings

Mercury, also known as quicksilver with the chemical label Hg, is one of only four metals that stay liquid at room temperature and is easily absorbed through the skin. Used for centuries in the medical industry, is has now become known as an environmental hazard and raised concerns about its use in industrial settings. It is a neuro-toxin that can severely damage the human nervous system and brain.

Together with lead, mercury causes thousands of poisonings a year, almost all of which come from broken thermometers and simple household items such as broken fluorescent light bulbs and certain latex paints. Many fungicides and pesticides also contain the element. There are several drugs and common vaccines that contain small amounts of it as an essential ingredient. It is also present in electrical switches, certain art supplies, blood pressure cuffs, and dental amalgams. If you’re interested in finding out more about them, you can visit the United States Food and Drug Administration Website for a full list.

Mercury poisoning is less prevalent than it was in those bad old days, but can still be a concern. The disease was commonly seen in hat-makers in the 18th century, since a Hg compound was widely used in making felt. Unaware of the danger of skin absorption of this chemical, hatters handled the felt, and over a period of time, went insane from the poisoning. This gave rise to the phrase “mad as a hatter,” which in turn led to Alice in Wonderland’s Mad Hatter character. The most common source of high levels of it today is consumption of mercury-contaminated fish.

The presence of mercury (CAS number is 7439-97-6) in the water causes a double problem, since it eventually builds up in fish that are eventually consumed by people. As a result, many types of fish now contain levels of Hg dangerous enough to be considered a serious hazard. In fact, methylmercury is now one of the main causes of the poisoning in humans. The element is released into the environment by several processes, including coal burning and the disposal of hazardous wastes.

The human body can not, unaided, process and remove it from the brain and nervous system. Therefore, in cases of its poisoning, radical therapies are required to eliminate the contaminant. Chelation therapy is the therapy currently used, in which chelating agents are introduced. Chelating agents can form bonds with the poisonous heavy metals, and then the compound created can be eliminated. In addition, it is dangerous to humans because it’s still being used in many aspects of daily life. By reducing it presence, it may be possible to also reduce its effects.

Three Types Of Surgical Gloves

Surgical gloves are much like doctors’ examination gloves, except they are of higher quality and are more expensive. They provide comfort and tactile sensitivity while providing barrier protection to surgeons and nurses during operating procedures. Choosing the right surgical glove can be an ordeal looking at the plethora of options available.

History
In 1894, William Stewart Halsted pioneered the widespread use of rubber gloves during surgery. Halsted was the first surgeon-in-chief and first professor of surgery at the Johns Hopkins Hospital within the university of the same name in Baltimore. He is often called the father of American surgery and the father of surgical rubber gloves. The first known use of them was by a German physician carrying out a gynecological operation in 1758. At this time, surgeons routinely operated in their everyday clothes with no more than an already bloodstained apron over the top.

In the 1840s, anatomists and pathologists began using rubber ones when they were conducting dissections. By January 2008, Johns Hopkins Hospital had phased out the use of latex surgical ones. As reported at the 2010 Annual Meeting of the Academy of Orthopaedic Surgeons in New Orleans, some surgeons believe that latex-free surgical products may be more likely to perforate during operations.

Latex Gloves
The latex glove, made from natural rubber latex, is a long-standing, popular choice.It provides excellent tactile sensitivity, allowing the surgeon to feel his way through the procedure. Latex also makes for a comfortable product. They are also highly elastic, making them easy to put on. Today, there are many options available due to improved technology. For instance, surgical products with polymer inner coating are available to provide ease of donning ones even if hands are damp or dry.

Polyisoprene Gloves
Polyisoprene (C5H8, CAS No. is 9003-31-0)surgical ones are made from synthetic polyisoprene which provide similar properties to latex (natural rubber). Of all material used to make surgical gloves, polyisoprene() is the most expensive material. In fact, polyisoprene has a molecular structure that is very similar to natural rubber. Polyisoprene is regarded as a “latex” product without the harmful protein found in latex which is responsible for latex allergies. Like other surgical materials, this product are available with polymer inner coating so donning gloves are easier even when hands are damp or dry.

Neoprene Gloves
Neoprene is also a synthetic material. It is often the choice for surgical gloves when latex is not an option. However, while it is a suitable substitute for latex in many respects, it is not as elastic. Like latex and polyisoprene ones, neoprene types are available with a polymer coating on the inside to make donning the gloves easier.

Mustard Products

Mustard seed is the seed of the mustard plant, a plant which has been cultivated for centuries for both its greens and seeds. They are used as a spice in many cultures, and they can be found in a wide of dishes. Prepared from the seed, its oil is a versatile oil that can be used for both therapeutic uses and culinary applications.

Mustard Seeds
As a general rule, they are spicy and piquant, a trait shared with other Brassicas. The flavor of them varies, depending on the varietal. Some of them have an extremely strong bite which has made it rather famous. The seeds may be black, brown, yellow, or white, depending on the species and cultivar. Many Westerners are familiar with yellow one.

When mustard seeds are used as a spice, there are a number of ways to utilize them. They can be added to dishes as they are cooking, in which case they are usually cracked to release their volatile flavor and aroma, and they are sometimes ground up and added to curry mixtures as well. Many cooks in places like India throw whole seeds into a cooking pot with some oil before they start cooking a dish, ensuring that the oil is flavored with the spice when the heated seeds pop.

People can also grind its seeds and keep the dry powder handy for mixing mustard as needed, and ingredients like water, cider vinegar, horseradish, honey, wine, and milk can also be mixed with ground seeds to make mustard.

Mustard Oil
As one of the more common types of seed found in the Mediterranean, the seeds produce an oil that is both aromatic and soothing to the skin. When it comes to the use of oils as a soothing topical agent, mustard oil(also known as Fats and Glyceridicoils, mustard and the CAS number is 8007-40-7) is considered to be helpful with the pain and discomfort associated with arthritis. The use of it as an ointment for stiff joints has a long history, and is still recommended by persons who prefer to use natural agents to treat various health ailments. Along with leaving relatively little residue, this oil provides a pleasant aroma that may also appeal to the user of the oil.

The oil that is allowed to reach the temperature necessary for smoking will actually achieve a smoother mustard flavor that will be very appealing. In cooking, it works differently from most other oils. With this oil, it is important to allow the oil to reach the smoking point before using the compound in stir-fry and other dishes that are prepared on a stovetop.

Sodium Hyaluronate Used For Knee Pain

Sodium hyaluronate( C28H44N2O23.Na), sometimes called as hyaluronate sodium, is an injected medication used to treat symptoms of osteoarthritis, such as pain. It is similar to the fluid found in human joints and also used to restore skin moisture, treat sores and eyes as well as reduce knee joint pain. It works by mimicking the effects of a natural substance found in the joints, called synovial fluid.

Benefits
For Osteoarthritis
Patients who experience excessive knee pain can have it treated by receiving an injection treatment of sodium hyaluronate from a doctor. The medication is injected directly into the knee joint and is a replacement for the loss of synovial fluid from the joints. The treatment “acts as a shock-absorber and lubricant as well as enhances the efficacy of the knee joint fluid,” according to the website Blue Medica.

For Eyes
Dry eye resulting from tear secretion problems can be treated with sodium hyaluronate drops. The drops have been a very effective substitute for natural tears. The treatment is so effective that the eye drops “increase precorneal tear film stability and corneal wettability and reduces the tear evaporation rate,” according to the website Access My Library.

For Skin
Sodium hyaluronate reduces flaking, dry and damaged skin by hydrating the skin and increasing its volume and density, which minimizes wrinkles, suggests the website Truth In Aging.

Dosage
Adults will typically be prescribed an injection of 20 milligrams (mg) of sodium hyaluronate. The doctor will administer a total of three to five injections, spaced one week apart. Patients will receive the shot directly into the knee to relieve osteoarthritis pain. After the injection, patients must carefully follow the doctor’s instructions regarding physical activity. They will usually be unable to engage in strenuous or weight-bearing activities for the next 48 hours, however some people may be able to participate in certain activities that do not last longer than one hour.

Side Effects
Some patients may appear side effects following an injection of sodium hyaluronate. They should inform the doctor about any side effects that persist or become bothersome, such as headache, stomach pain, and diarrhea. Nausea, vomiting, and loss of appetite may also occur. Some people may notice a few blue or purple patches on their skin, as well as itching and swelling of the knee. These side effects will typically diminish or go away completely as the patient’s body acclimates to sodium hyaluronate.

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Caffeine In Tea And Chocolate

A number of people cannot make it through a day without a caffeine fix. Some get it through a cup of coffee. Others get it with chocolate or tea. The substance exsits in chocolate, coffee and tea, present only in small amounts. For those who must avoid this component completely, this may be bad news. However, for those who can have a small amount of caffeine, the component in chocolate is not likely to be problematic unless one consumes vast quantities of chocolate on a regular basis.

Caffeine(C8H10N4O2) can help a person stay awake, alert, and energetic. Its consumption greater than 500 to 600 milligrams a day is not recommended. Large, grande, strong brewed cups of coffee can easily reach that level. Hot chocolate does even come close to a count that is considered questionable. However, too much amount can cause headaches, heart palpitations, insomnia, restlessness, and anxiety. It can be bothersome to some people and not have an effect on others.

The caffeine in chocolate varies according to the type of chocolate one chooses.The product that is unsweetened or is semi-sweet usually contains about five to 10 milligrams per ounce of chocolate. The alkaloid in chocolate with milk added is usually measured at five milligrams or less per ounce. Generally, the component is present in higher amounts, as the chocolate gets darker.

The caffeine in tea also can be compared to the same substance in chocolate. Green tea is much lower in caffeine than coffee, containing between 15-40 milligrams per eight-ounce cup. Black tea has an average of 50 milligrams per cup. Both green and black tea will have a higher amount rating depending upon amount of tea used and brewing time.

The average Hershey bar is approximately one and a half ounces of milk chocolate. If one eats the whole bar, this translates to consuming about seven and a half milligrams of caffeine(CAS No. 58-08-2). One would have to eat six bars in order to equal it in strong green tea, and seven and a half bars to equal in black tea. To match a cup of coffee, one would have to eat approximately 20 Hershey bars.

If one must strictly avoid caffeine in chocolate and other sources, those with a sweet tooth can still take heart. White chocolate does not contain this component, since those ingredients that make chocolate dark are absent in the white chocolate production process. One may still get sugar rush from white chocolate, but it will be absent the component in chocolate of the milk or dark varieties.

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How Are Blueprints Made?

Blueprinting a process of transferring architectural plans from drafts onto paper as a final design that is used by contractors and construction workers to build the design. When exposed, the solution sets into a dark blue color, leaving the unexposed portions white. The result is a traditional blueprint, also called a cyanoprint, a design in white against a blue background.

History
The solution used to coat the substrate for blueprints is made from potassium ferricyanide and ammonium ferric citrate. It was developed by Sir John Herschal, a British astronomer, in the mid 1800s. The chemicals will react with bright light to form ferric ferrocyanide, an insoluble blue pigment. Potentially, numerous blueprints could be made from a master drawing and easily distributed, at a cost much lower than that of conventional photographic reproduction.

Process
Contact printing is used to produce blueprints. First, a drawing is made on tracing paper, cloth, or another material which is transparent, allowing light through. The drawing is positioned over material soaked in a blueprint solution, and then exposed to a bright light. The resulting blueprint is chemically fixed and washed to remove chemical traces. It will be resistant to fading and marking, and is usually made on a durable material which can be rolled up and easily transported between offices and job sites.

Chemical Reaction
The first chemical reaction occurs when light hits the ammonium iron citrate. The energy of the light waves passes through the iron present, and excites the oxygen atoms until one finally bursts free. The ammonium ferric citrate becomes ammonium ferrous citrate as all the iron particles of the compound lose one oxygen component…except for those not exposed to the light, the iron under the tracing lines.

When the blueprint is immersed in the potassium ferricyanide solution, all of the ammonium ferrous citrate(also known as ferric ammonium citrate or ammonium iron(III) citrate, the CAS No. 1185-57-5) reacts to the chemicals and becomes a completely new compound, once known as “Prussian blue” because of its blue-colored qualities. This blue chemical clings to the paper, while the mixture that still has three oxygen atoms remains unchanged. When the blueprint is washed, only the Prussian blue remains, leaving the traced outline firmly intact.

Potential Uses
Modern advances in replication technology have allowed other techniques to replace the blueprint, although some firms continue to use blueprints for rendering. When marking up a blueprint, chalks in contrasting colors such as red and yellow are used, so that the markings are clearly visible. The edited blueprint is returned to the person who drafted it for the changes to be made, and then is printed again and checked. Once all parties are satisfied with the blueprint, it will be officially stamped, making it into a legal document which will be filed along with the other paperwork on the structure being built.

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Why Are Dry Erase Markers Dangerous?

Dry erase markers are special markers used for writing on whiteboards that are common in offices and households. In addition to using them on their accompanying whiteboards, you can: write on your mirrors and other glass surfaces; write on your desk; write the service miles and date on the inside of your car windshield; or let your kids decorate the windows for the holidays. The markers themselves are easily erased with a soft brush or cloth without the use of water, hence the name. There are several dangers associated with dry erase markers and their ingredients, some of which are toxic.

The product is an evolved form of the wet marker. A wet erase marker is used for overhead projector transparencies and was originally used on whiteboards and other plastic-like surfaces. The dry erase marker was first offered on the market in 1976 by the Sanford Corporation as the “Expo” marker, according to information provided on the Expo website. Sanford is the company that also developed the Sharpie marker. In 1986, the Expo 2 marker was released. This marker has less odor and an alcohol-based solvent as opposed to the much harsher chemical, methyl isobutyl ketone, that is found in the original Expo marker and other dry erase markers.

Methyl isobutyl ketone (MIK) is a solvent used in gums, resins, paints, varnishes and lacquers. It is a colorless, flammable liquid that is moderately soluble in water. Its odor is much like camphor.

Some brands of dry erase markers contain methyl isobutyl ketone, a chemical that can lead to liver problems, headaches and nausea with long-term exposure. According to a document from the Office of Environmental Health Hazard Assessment published by Paradise Valley Community College, exposure to this chemical is dangerous if it exceeds 15 minutes per day. Teachers and students that use dry erase markers containing this chemical for longer periods of time who also get the marker ink on their skin, where it can be absorbed or ingested, are at risk of developing such problems.

It is said that short-term exposure to MIK can irritate the eyes and nose, cause weakness, headache, nausea, vomiting, dizziness and coordination problems. Long-term effects are more severe and can include headaches, nausea, enlarged liver, burning in the eyes, intestinal pain, weakness and insomnia. There is no known remedy for long-term effects. Stop using dry erase markers with Methyl isobutyl ketone(also called ads 2-methyl-4-pentanone, 4-methyl-2-pentanone or isohexanone,CAS number 108-10-1) if any of the above side effects are experienced, and consult a physician if you feel you are suffering from long-term exposure effects.

The NIPC(National Inhalant Prevention Coalition) reports that depending on the level of dosage, an inhaler can experience “slight stimulation, feeling of less inhibition or loss of consciousness. The user can also suffer from Sudden Sniffing Death Syndrome.” This means the inhaler can die on the first, fifth or 50th use of an inhalant. Long-term effects include: potential Sudden Sniffing Death Syndrome; short-term memory loss; hearing loss; limb spasms; permanent brain damage; bone marrow damage; liver and kidney damage; and possible fetal effects similar to fetal alcohol syndrome.

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