Raw Materials

Methyl methacrylate is the basic molecule, or monomer, from which polymethyl methacrylate and many other acrylic plastic polymers are formed. The chemical notation for this material is CH₂=C(CH₃)

COOCH₃. It is written in this format, rather than the more common chemical notation C₅H₈O₂, to show the double bond (=) between the two carbon atoms in the middle. During polymerization, one leg of this double bond breaks and links up with the middle carbon atom of another methyl methacrylate molecule to start a chain. This process repeats itself until the final polymer is formed.

Methyl methacrylate may be formed in several ways. One common way is to react acetone [CH₃COCH₃] with sodium cyanide [NaCN] to produce acetone cyanhydrin [(CH₃)₂C(OH)CN]. This in turn is reacted with methyl alcohol [CH₃OH] to produce methyl methacrylate.

Other similar monomers such as methyl acrylate [CH₂=CHCOOCH,] and acrylonitrile [CH₂=CHCN] can be joined with methyl methacrylate to form different acrylic plastics. (See Figure 2) When two or more monomers are joined together, the result is known as a copolymer. Just as with methyl methacrylate, both of these monomers have a double bond on the middle carbon atoms that splits during polymerization to link with the carbon atoms of other molecules. Controlling the proportion of these other monomers produces changes in elasticity and other properties in the resulting plastic.

The Manufacturing Process

Acrylic plastic polymers are formed by reacting a monomer, such as methyl methacrylate, with a catalyst. A typical catalyst would be an organic peroxide. The catalyst starts the reaction and enters into it to keep it going, but does not become part of the resulting polymer.

Acrylic plastics are available in three forms: flat sheets, elongated shapes (rods and tubes), and molding powder. Molding powders are sometimes made by a process known as suspension polymerization in which the reaction takes place between tiny droplets of the monomer suspended in a solution of water and catalyst. This results in grains of polymer with tightly controlled molecular weight suitable for molding or extrusion.

Acrylic plastic sheets are formed by a process known as bulk polymerization. In this process, the monomer and catalyst are poured into a mold where the reaction takes place. Two methods of bulk polymerization may be used: batch cell or continuous. Batch cell is the most common because it is simple and is easily adapted for making acrylic sheets in thicknesses from 0.06 to 6.0 inches (0.16-15 cm) and widths from 3 feet (0.9 m) up to several hundred feet. The batch cell method may also be used to form rods and tubes. The continuous method is quicker and involves less labor. It is used to make sheets of thinner thicknesses and smaller widths than those produced by the batch cell method.

We will describe both the batch cell and continuous bulk polymerization processes typically used to produce transparent polymethyl methacrylic (PMMA) sheets.

Batch cell bulk polymerization

1. The mold for producing sheets is assembled from two plates of polished glass separated by a flexible "window-frame" spacer. The spacer sits along the outer perimeter of the surface of the glass plates and forms a sealed cavity between the plates. The fact that the spacer is flexible allows the mold cavity to shrink during the polymerization process to compensate for the volume contraction of the material as the reaction goes from individual molecules to linked polymers. In some production applications, polished metal plates are used instead of glass. Several plates may be stacked on top of each other with the upper surface of one plate becoming the bottom surface of the next higher mold cavity. The plates and spacers are clamped together with spring clamps.
2. An open comer of each mold cavity is filled with a pre-measured liquid syrup of methyl methacrylate monomer and catalyst. In some cases, a methyl methacrylate prepolymer is also added. A prepolymer is a material with partially formed polymer chains used to further help the polymerization process. The liquid syrup flows throughout the mold cavity to fill it.
3. The mold is then sealed and heat may be applied to help the catalyst start the reaction.
4. As the reaction proceeds, it may generate significant heat by itself. This heat is fanned off in air ovens or by placing the molds in a water bath. A programmed temperature cycle is followed to ensure proper cure time without additional vaporization of the monomer solution. This also prevents bubbles from forming. Thinner sheets may cure in 10 to 12 hours, but thicker sheets may require several days.
5. When the plastic is cured, the molds are cooled and opened. The glass or metal plates are cleaned and reassembled for the next batch.
6. The plastic sheets are either used as is or are annealed by heating them to 284-302°F (140-150°C) for several hours to reduce any residual stresses in the material that might cause warping or other dimensional instabilities.
7. Any excess material, or flash, is trimmed off the edges, and masking paper or plastic film is applied to the surface of the finished sheets for protection during handling and shipping. The paper or film is often marked with the material's brand name, size, and handling instructions. Conformance with applicable safety or building code standards is also noted.

Continuous bulk polymerization
The continuous process is similar to the batch cell process, but because the sheets are thinner and smaller, the process times are much shorter. The syrup of monomer and catalyst is introduced at one end of a set of horizontal stainless steel belts running parallel, one above the other. The distance between the belts determines the thickness of the sheet to be formed.

1. The belts hold the reacting monomer and catalyst syrup between them and move it through a series of heating and cooling zones according to a programmed temperature cycle to cure the material.
2. Electric heaters or hot air may then anneal the material as it comes out of the end of the belts.
3. The sheets are cut to size and masking paper or plastic film is applied.

Raw Materials

Aluminum numbers among the most abundant elements: after oxygen and silicon, it is the most plentiful element found in the earth's surface, making up over eight percent of the crust to a depth of ten miles and appearing in almost every common rock.

However, aluminum does not occur in its pure, metallic form but rather as hydrated aluminum oxide (a mixture of water and alumina) combined with silica, iron oxide, and titania.

The most significant aluminum ore is bauxite, named after the French town of Les Baux where it was discovered in 1821. Bauxite contains iron and hydrated aluminum oxide, with the latter representing its largest constituent material.

At present, bauxite is plentiful enough so that only deposits with an aluminum oxide content of forty-five percent or more are mined to make aluminum. Concentrated deposits are found in both the northern and southern hemispheres, with most of the ore used in the United States coming from the West Indies, North America, and Australia. Since bauxite occurs so close to the earth's surface, mining procedures are relatively simple. Explosives are used to open up large pits in bauxite beds, after which the top layers of dirt and rock are cleared away. The exposed ore is then removed with front end loaders, piled in trucks or railroad cars, and transported to processing plants. Bauxite is heavy (generally, one ton of aluminum can be produced from four to six tons of the ore), so, to reduce the cost of transporting it, these plants are often situated as close as possible to the bauxite mines.

The Manufacturing Process
Extracting pure aluminum from bauxite entails two processes. First, the ore is refined to eliminate impurities such as iron oxide, silica, titania, and water. Then, the resultant aluminum oxide is smelted to produce pure aluminum. After that, the aluminum is rolled to produce foil.

Refining—Bayer process

1# The Bayer process used to refine bauxite comprises four steps: digestion, clarification, precipitation, and calcination. During the digestion stage, the bauxite is ground and mixed with sodium hydroxide before being pumped into large, pressurized tanks. In these tanks, called digesters, the combination of sodium hydroxide, heat, and pressure breaks the ore down into a saturated solution of sodium aluminate and insoluble contaminants, which settle to the bottom.

2# The next phase of the process, clarification, entails sending the solution and the contaminants through a set of tanks and presses. During this stage, cloth filters trap the contaminants, which are then disposed of. After being filtered once again, the remaining solution is transported to a cooling tower.

3# In the next stage, precipitation, the aluminum oxide solution moves into a large silo, where, in an adaptation of the Deville method, the fluid is seeded with crystals of hydrated aluminum to promote the formation of aluminum particles. As the seed crystals attract other crystals in the solution, large clumps of aluminum hydrate begin to form. These are first filtered out and then rinsed.

4# Calcination, the final step in the Bayer refinement process, entails exposing the aluminum hydrate to high temperatures. This extreme heat dehydrates the material, leaving a residue of fine white powder: aluminum oxide.

Smelting

1# Smelting, which separates the aluminum-oxygen compound (alumina) produced by the Bayer process, is the next step in extracting pure, metallic aluminum from bauxite. Although the procedure currently used derives from the electrolytic method invented contemporaneously by Charles Hall and Paul-Louis-Toussaint Héroult in the late nineteenth century, it has been modernized. First, the alumina is dissolved in a smelting cell, a deep steel mold lined with carbon and filled with a heated liquid conductor that consists mainly of the aluminum compound cryolite.

2# Next, an electric current is run through the cryolite, causing a crust to form over the top of the alumina melt. When additional alumina is periodically stirred into the mixture, this crust is broken and stirred in as well. As the alumina dissolves, it electrolytically decomposes to produce a layer of pure, molten aluminum on the bottom of the smelting cell. The oxygen merges with the carbon used to line the cell and escapes in the form of carbon dioxide.

3# Still in molten form, the purified aluminum is drawn from the smelting cells, transferred into crucibles, and emptied into furnaces. At this stage, other elements can be added to produce aluminum alloys with characteristics appropriate to the end product, though foil is generally made from 99.8 or 99.9 percent pure aluminum. The liquid is then poured into direct chill casting devices, where it cools into large slabs called "ingots" or "reroll stock." After being annealed—heat treated to improve workability—the ingots are suitable for rolling into foil.

Alternative Method

An alternative method to melting and casting the aluminum is called "continuous casting." This process involves a production line consisting of a melting furnace, a holding hearth to contain the molten metal, a transfer system, a casting unit, a combination unit consisting of pinch rolls, shear and bridle, and a rewind and coil car. Both methods produce stock of thicknesses ranging from 0.125 to 0.250 inch (0.317 to 0.635 centimeter) and of various widths. The advantage of the continuous casting method is that it does not require an annealing step prior to foil rolling, as does the melting and casting process, because annealing is automatically achieved during the casting process.

Rolling foil

1# After the foil stock is made, it must be reduced in thickness to make the foil. This is accomplished in a rolling mill, where the material is passed several times through metal rolls called work rolls. As the sheets (or webs) of aluminum pass through the rolls, they are squeezed thinner and extruded through the gap between the rolls. The work rolls are paired with heavier rolls called backup rolls, which apply pressure to help maintain the stability of the work rolls. This helps to hold the product dimensions within tolerances. The work and backup rolls rotate in opposite directions. Lubricants are added to facilitate the rolling process. During this rolling process, the aluminum occasionally must be annealed (heat-treated) to maintain its workability.

* The reduction of the foil is controlled by adjusting the rpm of the rolls and the viscosity (the resistance to flow), quantity, and temperature of the rolling lubricants. The roll gap determines both the thickness and length of the foil leaving the mill. This gap can be adjusted by raising or lowering the upper work roll. Rolling produces two natural finishes on the foil, bright and matte. The bright finish is produced when the foil comes in contact with the work roll surfaces. To produce the matte finish, two sheets must be packed together and rolled simultaneously; when this is done, the sides that are touching each other end up with a matte finish. Other mechanical finishing methods, usually produced during converting operations, can be used to produce certain patterns.

2# As the foil sheets come through the rollers, they are trimmed and slitted with circular or razor-like knives installed on the roll mill. Trimming refers to the edges of the foil, while slitting involves cutting the foil into several sheets. These steps are used to produce narrow coiled widths, to trim the edges of coated or laminated stock, and to produce rectangular pieces. For certain fabricating and converting operations, webs that have been broken during rolling must be joined back together, or spliced. Common types of splices for joining webs of plain foil and/or backed foil include ultrasonic, heat-sealing tape, pressure-sealing tape, and electric welded. The ultrasonic splice uses a solid-state weld—made with an ultrasonic transducer—in the overlapped metal.

Finishing processes

1# For many applications, foil is used in I V / combination with other materials. It can be coated with a wide range of materials, such as polymers and resins, for decorative, protective, or heat-sealing purposes. It can be laminated to papers, paperboards, and plastic films. It can also be cut, formed into any shape, printed, embossed, slit into strips, sheeted, etched, and anodized. Once the foil is in its final state, it is packaged accordingly and shipped to the customer.

Making Lipstick
Materials
1# Wax :enables the mixture to be formed into the easily recognized shape of the cosmetic.
2# Oils such as mineral, caster, lanolin, or vegetable are added into the wax.
3# Fragrance and pigment
4# Preservatives and antioxidants, which prevent lipstick from becoming rancid.

And while every lipstick contains these components, a wide variety of other ingredients can also be included to make the substance smoother or glossy or to moisten the lips.

In general, wax and oil make up about 60% of the lipstick (by weight), with alcohol and pigment accounting for another 25 percent (by weight).

Fragrance is always added to lipstick, but accounts for one percent or less of the mixture. In addition to using lipstick to color the lips, there are also lip liners and pencils. The manufacturing methods described here will just focus on lipstick and lip balms.

Procedures

Melting and mixing

1# First, the raw ingredients for the lipstick are melted and mixed—separately because of the different types of ingredients used. One mixture contains the solvents, a second contains the oils, and a third contains the fats and waxy materials. These are heated in separate stainless steel or ceramic containers.

2# The solvent solution and liquid oils are then mixed with the color pigments. The mixture passes through a roller mill, grinding the pigment to avoid a "grainy" feel to the lipstick. This process introduces air into the oil and pigment mixture, so mechanical working of the mixture is required. The mixture is stirred for several hours; at this point some producers use vacuum equipment to withdraw the air.

# 3 After the pigment mass is ground and mixed, it is added to the hot wax mass until a uniform color and consistency is obtained. The fluid lipstick can then be strained and molded, or it may be poured into pans and stored for future molding.

# 4 If the fluid lipstick is to be used immediately, the melt is maintained at temperature, with agitation, so that trapped air escapes. If the lipstick mass is stored, before it is used it must be reheated, checked for color consistency, and adjusted to specifications, then maintained at the melt temperature (with agitation) until it can be poured.

As expected, lipsticks are always prepared in batches because of the different color pigments that can be used. The size of the batch, and the number of tubes of lipstick produced at one time, will depend on the popularity of the particular shade being produced. This will determine the manufacturing technique (automated or manual) that is used. Lipstick may be produced in highly automated processes, at rates of up to 2,400 tubes an hour, or in essentially manual operations, at rates around 150 tubes per hour. The steps in the process basically differ only in the volume produced.

Molding

5# Once the lipstick mass is mixed and free of air, it is ready to be poured into the tube. A variety of machine setups are used, depending on the equipment that the manufacturer has, but high volume batches are generally run through a melter that agitates the lipstick mass and maintains it as a liquid. For smaller, manually run batches, the mass is maintained at the desired mix temperature, with agitation, in a melter controlled by an operator.

6# The melted mass is dispensed into a mold, which consists of the bottom portion of the metal or plastic tube and a shaping portion that fits snugly with the tube. Lipstick is poured "up-side down" so that the bottom of the tube is at the top of the mold. Any excess is scraped from the mold.

7# The lipstick is cooled (automated molds are kept cold; manually produced molds are transferred to a refrigeration unit) and separated from the mold, and the bottom of the tube is sealed. The lipstick then passes through a flaming cabinet (or is flamed by hand) to seal pinholes and improve the finish. The lipstick is visually inspected for air holes, mold separation lines, or blemishes, and is reworked if necessary.

8# For obvious reasons, rework of the lipstick must be limited, demonstrating the importance of the early steps in removing air from the lipstick mass. Lipstick is reworked by hand with a spatula. This can be done in-line, or the tube can be removed from the manufacturing process and reworked.

Making Lip Gloss
Materials

Beeswax	25
Mineral Oil	45
White petrolatum	20
Isopropilmiristat	10

Aspirin is one of the safest and least expensive pain relievers on the marketplace. While other pain relievers were discovered and manufactured before aspirin, they only gained acceptance as over-the-counter drugs in Europe and the United States after aspirin's success at the turn of the twentieth century.

Aspirin can be used to fight a host of health problems: cerebral thromboses (with less than one tablet a day); general pain or fever (two to six tablets a day; and diseases such as rheumatic fever, gout, and rheumatoid arthritis. The drug is also beneficial in helping to ward off heart attacks. In addition, biologists use aspirin to interfere with white blood cell action, and molecular biologists use the drug to activate genes.

The wide range of effects that aspirin can produce made it difficult to pinpoint how it actually works, and it wasn't until the 1970s that biologists hypothesized that aspirin and related drugs (such as ibuprofen) work by inhibiting the synthesis of certain hormones that cause pain and inflammation. Since then, scientists have made further progress in understanding how aspirin works. They now know, for instance, that aspirin and its relatives actually prevent the growth of cells that cause inflammation

Aspirin Raw Materials

To produce hard aspirin tablets, corn starch and water are added to the active ingredient (acetylsalicylic acid) to serve as both a binding agent and filler, along with a lubricant. Binding agents assist in holding the tablets together; fillers (diluents) give the tablets increased bulk to produce tablets of adequate size. A portion of the lubricant is added during mixing and the rest is added after the tablets are compressed. Lubricant keeps the mixture from sticking to the machinery. Possible lubricants include: hydrogenated vegetable oil, stearic acid, talc, or aluminum stearate. Scientists have performed considerable investigation and research to isolate the most effective lubricant for hard aspirin tablets.

Chewable aspirin tablets contain different diluents, such as mannitol, lactose, sorbitol, sucrose, and inositol, which allow the tablet to dissolve at a faster rate and give the drug a pleasant taste. In addition, flavor agents, such as saccharin, and coloring agents are added to chewable tablets. The colorants currently approved in the United States include: FD&C Yellow No. 5, FD&C Yellow No. 6, FD&C Red No.3, FD&C Red No. 40, FD&C Blue No. 1, FD&C Blue No. 2, FD&C Green No. 3, a limited number of D&C colorants, and iron oxides.

Aspirin Manufacturing Process

Aspirin tablets are manufactured in different shapes. Their weight, size, thickness, and hardness may vary depending on the amount of the dosage. The upper and lower surfaces of the tablets may be flat, round, concave, or convex to various degrees. The tablets may also have a line scored down the middle of the outer surface, so the tablets can be broken in half, if desired. The tablets may be engraved with a symbol or letters to identify the manufacturer.

Aspirin tablets of the same dosage amount are manufactured in batches. After careful weighing, the necessary ingredients are mixed and compressed into units of granular mixture called slugs. The slugs are then filtered to remove air and lumps, and are compressed again (or punched) into numerous individual tablets. (The number of tablets will depend on the size of the batch, the dosage amount, and the type of tablet machine used.) Documentation on each batch is kept throughout the manufacturing process, and finished tablets undergo several tests before they are bottled and packaged for distribution.

The procedure for manufacturing hard aspirin tablets, known as dry-granulation or slugging, is as follows:

Weighing
* 1 The corn starch, the active ingredient, and the lubricant are weighed separately in sterile canisters to determine if the ingredients meet pre-determined specifications for the batch size and dosage amount.

Mixing

* 2 The corn starch is dispensed into cold purified water, then heated and stirred until a translucent paste forms. The corn starch, the active ingredient, and part of the lubricant are next poured into one sterile canister, and the canister is wheeled to a mixing machine called a Glen Mixer. Mixing blends the ingredients as well as expels air from the mixture.

* 3 The mixture is then mechanically separated into units, which are generally from 7/8 to 1 inches (2.22 to 2.54 centimeters) in size. These units are called slugs.

Dry screening
* 4 Next, small batches of slugs are forced through a mesh screen by a hand-held stainless steel spatula. Large batches in sizable manufacturing outlets are filtered through a machine called a Fitzpatrick mill. The remaining lubricant is added to the mixture, which is blended gently in a rotary granulator and sifter. The lubricant keeps the mixture from sticking to the tablet machine during the compression process.

Compression
* 5 The mixture is compressed into tablets either by a single-punch machine (for small batches) or a rotary tablet machine (for large scale production). The majority of single-punch machines are power-driven, but hand-operated models are still available. On single-punch machines, the mixture is fed into one tablet mold (called a dye cavity) by a feed shoe, as follows:
o The feed shoe passes over the dye cavity and releases the mixture. The feed shoe then retracts and scrapes all excess mixture away from the dye cavity.
o A punch—a short steel rod—the size of the dye cavity descends into the dye, compressing the mixture into a tablet. The punch then retracts, while a punch below #

* the dye cavity rises into the cavity and ejects the tablet.
* As the feed shoe returns to fill the dye cavity again, it pushes the compressed tablet from the dye platform.

# On rotary tablet machines, the mixture runs through a feed line into a number of dye cavities which are situated on a large steel plate. The plate revolves as the mixture is dispensed through the feed line, rapidly filling each dye cavity. Punches, both above and below the dye cavities, rotate in sequence with the rotation of the dye cavities. Rollers on top of the upper punches press the punches down onto the dye cavities, compressing the mixture into tablets, while roller-activated punches beneath the dye cavities lift up and eject the tablets from the dye platform

Testing
* 6 The compressed tablets are subjected to a tablet hardness and friability test, as well as a tablet disintegration test (see Quality Control section below).

Bottling and packaging
* 7 The tablets are transferred to an automated bottling assembly line where they are dispensed into clear or color-coated polyethylene or polypropylene plastic bottles or glass bottles. The bottles are topped with cotton packing, sealed with a sheer aluminum top, and then sealed with a plastic and rubber child-proof lid. A sheer, round plastic band is then affixed to the circular edge of the lid. It serves as an additional seal to discourage and detect product tampering.
* 8 The bottles are then labeled with product information and an expiration date is affixed. Depending on the manufacturer, the bottles are then packaged in individual cardboard boxes. The packages or bottles are then boxed in larger cardboard boxes in preparation for distribution to distributors

Where To Learn More Books
HIJSA'S Pharmaceutical Dispensing, 6th edition, Mack Publishing Company, 1966.
History of Pharmacy, 4th edition, The American Institute of History of Pharmacy, 1986.
An Introduction to Pharmaceutical Formulation, Pergamon Press, 1965.

Mann, Charles C. The Aspirin Wars: Money, Medicine & One Hundred Years of Rampant Competition. Alfred A. Knopf, Inc. 1991.

Remington's Pharmaceutical Sciences, 17th edition, Mack Publishing, 1985.
Periodicals

Draper, Roger. "A Pharmaceutical Cinderella (History of Aspirin)," The New Leader. January 13, 1992, p. 16.

Weissmann, Gerald. "Aspirin," Scientific American. January, 1991, pp. 84-90.

Wickens, Barbara. "Aspirin: What's in a Name?," Maclean's. July 16, 1990, p. 40.
—Greg Ling

Drying and husking the cherries

1 First, the coffee cherries must be harvested, a process that is still done manually. Next, the cherries are dried and husked using one of two methods. The dry method is an older, primitive, and labor-intensive process of distributing the cherries in the sun, raking them several times a day, and allowing them to dry. When they have dried to the point at which they contain only 12 percent water, the beans' husks become shriveled. At this stage they are hulled, either by hand or by a machine.

2 In employing the wet method, the hulls are removed before the beans have dried. Although the fruit is initially processed in a pulping machine that removes most of the material surrounding the beans, some of this glutinous covering remains after pulping. This residue is removed by letting the beans ferment in tanks, where their natural enzymes digest the gluey substance over a period of 18 to 36 hours. Upon removal from the fermenting tank, the beans are washed, dried by exposure to hot air, and put into large mechanical stirrers called hullers. There, the beans' last parchment covering, the pergamino, crumbles and falls away easily. The huller then polishes the bean to a clean, glossy finish.

Cleaning and grading the beans

3 The beans are then placed on a conveyor belt that carries them past workers who remove sticks and other debris. Next, they are graded according to size, the location and altitude of the plantation where they were grown, drying and husking methods, and taste. All these factors contribute to certain flavors that consumers will be able to select thanks in part to the grade.

4 Once these processes are completed, workers select and pack particular types and grades of beans to fill orders from the various roasting companies that will finish preparing the beans. When beans (usually robusta) are harvested under the undesirable conditions of hot, humid countries or coastal regions, they must be shipped as quickly as possible, because such climates encourage insects and fungi that can severely damage a shipment.

5 When the coffee beans arrive at a roasting plant, they are again cleaned and sorted by mechanical screening devices to remove leaves, bark, and other remaining debris. If the beans are not to be decaffeinated, they are ready for roasting.

Decaffeinating

6 If the coffee is to be decaffeinated, it is now processed using either a solvent or a water method. In the first process, the coffee beans are treated with a solvent (usually methylene chloride) that leaches out the caffeine. If this decaffeination method is used, the beans must be thoroughly washed to remove traces of the solvent prior to roasting. The other method entails steaming the beans to bring the caffeine to the surface and then scraping off this caffeine-rich layer.

Roasting

7 The beans are roasted in huge commercial roasters according to procedures and specifications which vary among manufacturers (specialty shops usually purchase beans directly from the growers and roast them on-site). The most common process entails placing the beans in a large metal cylinder and blowing hot air into it. An older method, called singeing, calls for placing the beans in a metal cylinder that is then rotated over an electric, gas, or charcoal heater.

Regardless of the particular method used, roasting gradually raises the temperature of the beans to between 431 and 449 degrees Fahrenheit (220-230 degrees Celsius). This triggers the release of steam, carbon monoxide, carbon dioxide, and other volatiles, reducing the weight of the beans by 14 to 23 percent. The pressure of these escaping internal gases causes the beans to swell, and they increase their volume by 30 to 100 percent. Roasting also darkens the color of the beans, gives them a crumbly texture, and triggers the chemical reactions that imbue the coffee with its familiar aroma (which it has not heretofore possessed).

8 After leaving the roaster, the beans are placed in a cooling vat, wherein they are stirred while cold air is blown over them. If the coffee being prepared is high-quality, the cooled beans will now be sent through an electronic sorter equipped to detect and eliminate beans that emerged from the roasting process too light or too dark.

9 If the coffee is to be pre-ground, the manufacturer mills it immediately after roasting. Special types of grinding have been developed for each of the different types of coffee makers, as each functions best with coffee ground to a specific fineness.

Instant coffee

10 If the coffee is to be instant, it is I V brewed with water in huge percolators after the grinding stage. An extract is clarified from the brewed coffee and sprayed into a large cylinder. As it falls downward through this cylinder, it enters a warm air stream that converts it into a dry powder.

Packaging

11 Because it is less vulnerable to flavor and aroma loss than other types of coffee, whole bean coffee is usually packaged in foil-lined bags. If it is to retain its aromatic qualities, pre-ground coffee must be hermetically sealed: it is usually packaged in impermeable plastic film, aluminum foil, or cans. Instant coffee picks up moisture easily, so it is vacuum-packed in tin cans or glass jars before being shipped to retail stores.

Swimming pool cleaner Formula
Soap Powder 25 gr
Sodium Carbonate 50 gr
Trisodium Posphate 20 gr
Sodium Metaphosphate 5 gr


Porcelein Cleaner Formula
HCl 332%
Aqudest 44 cc
Nonoxynol 2.5%
parfume up to you
Color Agent up to you

Formula #1

Ammonium Lautyl Sulphate 2%
Nonoxynol 2.5 %
Formaldehyde 1 oz / gal
Parfume as wish

Formula #2
Carbon TetraChloride 60 cc
Gasoline 40 cc
AmylAcetate 0.5 cc

thicker use :Polyethilenglycol

Mix these formula to make cleaner

Formula #1
Formalin 1 oz
Glycerin 2 oz
Alcohol 1 gal

Formula #2
Ammnoia 25% 7 cc
Oleum Olivarum 14 cc
Aquadest 8 cc

Formula #3
Ammonium Lauryl Sulfate 30%
Ammonium Liquide 25%
IPA 20%
Butylcellosolve 25%
parfume

Formula #4
IPA 100 gr
Ammonia 20 gr
Sod.Lauryl-ether-sulphate 20 gr
TSP or STPP 40 gr
Aquadest 820 gr

So, do you think water puts out fires? You wrong! water can ignite fire.

Mixture: ammonium nitrate + ammonium chloride + iodine + zinc dust.

When a drop or two of water is added, the ammonium nitrate forms nitric acid which reacts with the zinc to produce hydrogen and heat. The heat vaporizes the iodine (giving off purple smoke) and the ammonium chloride (becomes purple when mixed with iodine vapor). It will ignite the hydrogen and begin
burning.


Ammonium nitrate: 8 grams
Ammonium choride: 1 gram
Zinc dust : 8 grams
Iodine crystals : 1 gram

Face Paint
1. Break out a muffin tin or empty egg carton.
2. Spoon some cold cream into the tin or carton. The amount you use is up to you. It will depend on how much paint you need in the end.
3. Mix 1 to 2 drops of various colors food coloring into each cup. Feel free to mix colors to create your own hues.

Naturan Paint
1. Collect your pigment - try using chalk dust, talc, paprika, turmeric, chilli powder etc.
2. Add a little bit of gum arabic to the powder and mix to a paste
3. Thin with water to use, or let it harden and use later by re-mixing with a wet brush

Use your imagination and experiment, see what you can find to paint with! Grind materials down with a pestle and mortar or a plastic bag and a rolling pin, as fine as you can get it.
Try using your paints on various surfaces - make a card with your paints and then you can proudly tell the recipient all about how to make paint aswell.

Kid-Friendly Watercolors
1. Decide which colors you want to paint with and find a powdered drink mix that matches that color.
2. Empty the different colored powdered drink mixes into their own cups. If you're feeling adventurous, mix some of the colors together.
3. Add 2 tbsp. of warm water to each cup and stir until completely mixed. The paint's now ready to hit the paper.

Easy Face Paint
1. Separate colors with a muffin tin or an egg carton.
2. Place a spoonful of cold cream into each cup.
3. Add 1 or 2 drops of different colors of food coloring to the cold cream, and stir.
4. Apply the face paint using a clean paintbrush or cotton swabs.


Spiffy-Sniffy Watercolors
1. Use a small cup for each color.
2. Mix one package of powdered drink mix (Kool-Aid) with 2 tablespoons of warm water for each color.
3. Stir until the powder dissolves.
4. Once all of the colors are prepared, use a clean paintbrush to paint sweet-smelling pictures.

Window Paint
Turn your windows, patio doors and mirrors into works of art.
Mix together equal parts dishwashing liquid and washable liquid paint or powdered tempera. Children will love the process of painting and adults will love the end result: the paint wipes off easily with a dry paper towel.

Foamy Bath Paint
1. simply mix together shaving cream with a drop of food coloring.
2. Dip a paintbrush, or better yet, your fingers, into the mix
3. start creating!


Water-Based Paint
1. Choose a dry pigment to make into paint. Put a small amount onto a flat surface.
2. Use a palette knife to make a hole in the center of the pigment.
3. Pour a little water into the hole. Too much water will make the paint runny, so start with a very small amount of water and add more as needed.
4. Blend the water and pigment together with the knife. You want to create a smooth, evenly distributed paste.
5. Add the paste to a water-based paint binder. You can choose between acrylic, casein, egg tempera, watercolors or gouache. You can also use the paste to tint plaster or concrete. Now you're ready to paint.

Original on http://chemistry.about.com

A liquid magnet or ferrofluid is a colloidal mixture of magnetic particles (~10 nm in diameter) in a liquid carrier. The carrier contains a surfactant to prevent the particles from sticking together. Ferrofluids can be suspended in water or in an organic fluid. A typical ferrofluid is about 5% magnetic solids, 10% surfactant, and 85% carrier, by volume. One type of ferrofluid you can make uses magnetite for the magnetic particles, oleic acid as the surfactant, and kerosene as the carrier fluid to suspend the particles.

Several people have asked me if they can make substitutions for the oleic acid and the kerosene. The answer is yes, though changing the chemicals will change the characteristics of the ferrofluid somewhat. You can try other surfactants and other organic solvents. The surfactant must be soluble in the solvent.


When no external magnetic field is present the fluid is not magnetic and the orientation of the magnetite particles is random. However, when an external magnetic field is applied, the magnetic moments of the particles align with the magnetic field lines. When the magnetic field is removed, the particles return to random alignment. These properties can be used to make a liquid that changes its density depending on the strength of the magnetic field and that can form fantastic shapes.

You can find ferrofluids in high-end speakers and in the laser heads of some CD and DVD players. They are used in low friction seals for rotating shaft motors and computer disk drive seals. You could open a computer disk drive or a speaker to get to the liquid magnet, but it's pretty easy (and fun) to make your own ferrofluid.

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Material

Safety Considerations
This procedure uses flammable substances and generates heat and toxic fumes. Please wear safety glasses and skin protection, work in a well-ventilated area, and be familiar with the safety data for your chemicals. Ferrofluid can stain skin and clothing. Keep it out of reach of children and pets. Contact your local poison control center if you suspect ingestion (risk of iron poisoning; carrier is kerosene).

Materials
oleic acid (may be found in some pharmacies, craft, and health food stores)
household ammonia
PCB etchant (ferric chloride solution) - from an electronics store or you can make your ferric chloride or ferrous chloride solution or you can use magnetite or magnetic hematite powder if you have either of those minerals handy (magnetic hematite is an inexpensive mineral used in jewelry)
distilled water
steel wool
a magnet
kerosene
heat source
2 beakers or measuring cups
a plastic syringe or medicine cup (something to measure 10 ml)
coffee filters

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procedures

The magnetic particles in this ferrofluid consist of magnetite. If you aren't starting with magnetite, then the first step is to prepare it. This is done by reducing the ferric chloride (FeCl3) in PCB etchant to ferrous chloride (FeCl2). Ferric chloride is then reacted to produce magnetite. Commercial PCB etchant is usually 1.5M ferric chloride, to yield 5 grams of magnetite. If you are using a stock solution of ferric chloride, follow the procedure using a 1.5M solution.

1.Pour 10 ml of PCB etchant and 10 ml of distilled water in a glass cup.

2.Add a piece of steel wool to the solution. Mix the liquid until you get a color change. The solution should become bright green (green is the FeCl2).

3. Filter the liquid through filter paper or a coffee filter. Keep the liquid; discard the filter.

4. Precipitate the magnetite out of the solution. Add 20 ml of PCB etchant (FeCl3) to the green solution (FeCl2). If you are using stock solutions of ferric and ferrous chloride, keep in mind FeCl3 and FeCl2 react in a 2:1 ratio.

5. Stir in 150 ml of ammonia. The magnetite, Fe3O4, will fall out of solution. This is the product you want to collect.

The next step is to take the magnetite and suspend it in the carrier solution.

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The magnetic particles need to be coated with a surfactant so that they won't stick together when magnetized. Finally, the coated particles will be suspended in a carrier so the magnetic solution will flow like a liquid. Since you are going to be working with ammonia and kerosense, prepare the carrier in a well-ventilated area, outdoors or under a fume hood.

1 Heat the magnetite solution to just below boiling.

2 Stir in 5 ml oleic acid. Maintain the heat until the ammonia evaporates (approximately an hour).

3 Remove the mixture from heat and allow it to cool. The oleic acid reacts with ammonia to form ammonium oleate. Heat allows the oleate ion to enter solution, while the ammonia escapes as a gas (which is why you need ventilation). When the oleate ion binds to a magnetite particle it is reconverted to oleic acid.

4 Add 100 ml kerosene to the coated magnetite suspension. Stir the suspension until most of the black color has been transferred into the kerosene. Magnetite and oleic acid are insoluble in water, while oleic acid is soluble in kerosene. The coated particles will leave the aqueous solution in favor of the kerosene. If you make a substitution for the kerosene, you want a solvent with the same property: the ability to dissolve the oleic acid but not uncoated magnetite.

5Decant and save the kerosene layer. Discard the water. The magnetite plus oleic acid plus kerosene is the ferrofluid.


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Ferrofluid is very strongly attracted to magnets, so maintain a barrier between the liquid and the magnet (e.g., sheet of glass). Avoid splashing the liquid. Both kerosene and iron are toxic, so do not ingest the ferrofluid or allow skin contact (don't stir it with a finger or play with it).

Here are some ideas for activities involving your liquid magnet ferrofluid. You can:

-Use a strong magnet to float a penny on top of the ferrofluid.

- Use magnets to drag the ferrofluid up the sides of a container.
- Bring a magnet close to the ferrofluid to see spikes form, following the lines of the magnetic field.
Explore the shapes you can form using a magnet and the ferrofluid. Store your liquid magnet away from heat and flame. If you need to dispose of your ferrofluid at some point, dispose of it the way you would dispose of kerosene. Have fun!