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  1. Triethanolamine - Wikipedia

    en.wikipedia.org/wiki/Triethanolamine
    • Production
    • Applications
    • Safety and Regulation
    • See Also

    Triethanolamine is produced from the reaction of ethylene oxide with aqueous ammonia, also produced are ethanolamine and diethanolamine. The ratio of the products can be controlled by changing the stoichiometryof the reactants.

    Triethanolamine is used primarily in making surfactants, such as for emulsifier. It is a common ingredient in formulations used for both industrial and consumer products. The triethanolamine neutralizes fatty acids, adjusts and buffers the pH, and solubilizes oils and other ingredients that are not completely soluble in water. Triethanolammonium salts in some cases are more soluble than salts of alkali metals that might be used otherwise, and results in less alkaline products than would from using alkali metal hydroxides to form the salt. Some common products in which triethanolamine is found are sunscreen lotions, liquid laundry detergents, dishwashing liquids, general cleaners, hand sanitizers, polishes, metalworking fluids, paints, shaving cream and printing inks.

    Allergic reactions

    A 1996 study found that triethanolamine (TEOA) occasionally causes contact allergy. A 2001 study found TEOA in a sunscreen caused an allergic contact dermatitis. A 2007 study found TEOA in ear drops caused a contact allergy. Systemic and respiratory tract (RT) toxicity was analyzed for 28 days in a nose specific inhalation 2008 study in Wistar rats; TEOA seems to be less potent in regard to systemic toxicity and RT irritancy than diethanolamine (DEA). Exposure to TEOA resulted in focal inflam...

    Tumors

    Reports indicated that TEOA causes an increased incidence of tumor growth in the liver in female B6C3F1 mice, but not in male mice or in Fischer 344 rats.A 2004 study concluded "TEOA may cause liver tumors in mice via a choline-depletion mode of action and that this effect is likely caused by the inhibition of choline uptake by cells."

    Environmental toxicity

    A 2009 study found that TEOA has potential acute, sub-chronic and chronic toxicity properties in respect to aquatic species.

    • 102-71-6
    • 21.60 °C; 70.88 °F; 294.75 K
    • C₆H₁₅NO₃
    • miscible
  2. Sales and operations planning - Wikipedia

    en.wikipedia.org/wiki/Sales_and_operations_planning
    • Definitions
    • The Planning Process
    • Best Practices
    • See Also
    • External Links

    APICS defines S&OP as the "function of setting the overall level of manufacturing output (production plan) and other activities to best satisfy the current planned levels of sales (sales plan and/or forecasts), while meeting general business objectives of profitability, productivity, competitive customer lead times, etc., as expressed in the overall business plan." Institute for Supply Management defines it as "working cross-functionally with internal business units to forecast anticipated demand, inventory, supply and customer lead times based on the sales forecast, actual demand and capacity forecast." One of its primary purposes is to establish production rates that will achieve management’s objective of maintaining, raising, or lowering inventories or backlogs, while usually attempting to keep the workforce relatively stable. It must extend through a planning horizon sufficient to plan the labor, equipment, facilities, material, and finances required to accomplish the production...

    S&OP is the result of monthly planning activities. It is usually based on an Annual Operations Plan (AOP) that acts as the company's annual target in terms of sales and supply. Therefore, the sales and operations plans are a means to gradually accomplish the AOP targets – by linking monthly sales and marketing planning directly to the operations side of a business.The process for deciding upon the monthly S&OP is illustrated in the figure below. 1. Monthly S&OP Process The planning horizon for a typical S&OP process is long term and extends over 18–36 months. The selection of a time horizon is an important decision and there are different factors that influence this decision including type of industry, product characteristics, and the time of the year when S&OP planning takes place.Additionally, the S&OP process is conducted at an aggregate level. The focus is commonly on product families and not every single product.

    S&OP best practices share a common set of approaches: 1. Rely on a phased approach: S&OP is much more an integrated set of business processes and technologies than a single, all-encompassing process or technology. If you just focus on the implementation of a new technology and think that S&OP will miraculously take shape, you're wrong. 2. Develop an "outside-in" sequence of S&OP initiatives: typically, the events that will have the most profound and negative impact on your sales and operations planning are those outside of your control. For the most part, these are due to the decisions and actions of your customers, partners, and competitors, which have a direct impact on your revenue and your competitor's strategy. 3. Focus on more information, less data: another key to successful S&OP is clean, current, and accurate data. Plans are often slowed down by the effort of gathering data that has minimal importance to the overall project. It is important to ensure that you know exactly w...

    Palmatier, George E., "The Need to Lead"
    The Evolution of S&OP by Dick Ling, Andy Coldrick and Chris Turner
  3. Daiquiri - Wikipedia

    en.wikipedia.org/wiki/Daiquiri
    • Origins
    • Variations
    • Frozen Daiquiri
    • See Also
    • References
    • External Links

    Daiquirí is also the name of a beach and an iron mine near Santiago de Cuba, and is a word of Taíno origin. The drink was supposedly invented by an American mining engineer named Jennings Cox, who was in Cuba at the time of the Spanish–American War. It is also possible that William A. Chanler, a US congressman who purchased the Santiago iron mines in 1902, introduced the daiquiri to clubs in New Yorkin that year. Originally the drink was served in a tall glass packed with cracked ice. A teaspoon of sugar was poured over the ice and the juice of one or two limes was squeezed over the sugar. Two or three ounces of white rum completed the mixture. The glass was then frosted by stirring with a long-handled spoon. Later the daiquiri evolved to be mixed in a shaker with the same ingredients but with shaved ice. After a thorough shaking, it was poured into a chilled coupe glass. Consumption of the drink remained localized until 1909, when Rear Admiral Lucius W. Johnson, a U.S. Navy medical...

    Strawberry daiquiri– a blender drink of puréed whole strawberries, rum, cane sugar and lime juice
    Hemingway daiquiri (Hemingway Special) – or papa doble – two and a half jiggers of white rum, juice of two limes and half a grapefruit, six drops of maraschinoliqueur, without sugar.
    Banana daiquiri– regular daiquiri with half a banana.
    Avocado daiquiri– regular daiquiri with half an avocado.

    A wide variety of alcoholic mixed drinks made with finely pulverized ice are often called frozen daiquirí. These drinks can also be combined and poured from a blender, eliminating the need for manual pulverisation and producing a texture similar to a smoothie. On larger scales, such drinks are often commercially made in larger machines, and come in a wide variety of flavors made with various alcohol or liquors.[citation needed] Another way to create a frozen daiquiri (mostly fruit-flavored variants) is by using frozen limeade, providing the required texture, sweetness and sourness all at once. Variations on the frozen daiquiri include: 1. Old Rose Daiquiri:strawberry syrup and rum along with two teaspoons of sugar and lime juice 2. Mulata Daiquiri:rum mixed with either coffee or chocolate liqueur and with fresh lime juice and sugar syrup

    Digital Images regarding Jennings Cox including an original daiquirí recipe from the Carmen Puig Collection held by the Cuban Heritage Collectionof the University of Miami Libraries
    A collection of Daiquiri Cocktail Recipesand variations
    Slush machine made Daiquiri frozen Cocktails
  4. Cable tray - Wikipedia

    en.wikipedia.org/wiki/Cable_tray
    • Types
    • Materials Used
    • Fire Safety Concerns and Solutions
    • See Also

    Several types of tray are used in different applications. A solid-bottom tray provides the maximum protection to cables, but requires cutting the tray or using fittings to enter or exit cables. A deep, solid enclosure for cables is called a cable channel or cable trough. A ventilated tray has openings in the bottom of the tray, allowing some air circulation around the cables, water drainage, and allowing some dust to fall through the tray. Small cables may exit the tray through the ventilation openings, which may be either slots or holes punched in the bottom. A ladder tray has the cables supported by a traverse bar, similarly to the rungs of a ladder, at regular intervals on the order of 4 to 12 inches (100 to 300 mm). Ladder and ventilated trays may have solid covers to protect cables from falling objects, dust, and water. Tray covers for use outdoors or in dusty locations may have a peaked shape to shed debris including dust, ice or snow. Lighter cable trays are more appropriate...

    Common cable trays are made of galvanized steel, stainless steel, aluminum, or glass-fiber reinforced plastic. The material for a given application is chosen based on where it will be used.Galvanized tray may be made of pre-galvanized steel sheet fabricated into tray, or may be hot-dip galvanized after fabrication. When galvanized tray is cut to length in the field, usually the cut surface will be painted with a zinc-rich compound to protect the metal from corrosion.

    Combustible cable jackets may catch on fire and cable fires can thus spread along a cable tray within a structure. This is easily prevented through the use of fire-retardant cable jackets, or fireproofingcoatings applied to installed cables. Heavy coatings or long fire-stops may require adjustment of the cable current ratings, since such fireproofing measures may reduce the heat dissipation of installed cables. Regular housecleaning is important for safety, as cable trays are often installed in hard to reach places. Combustible dust and clutter may accumulate if the trays are not routinely checked and kept clean. Plastic and fibreglass reinforced plastic cable trays are combustible; the effect is mitigated through the use of fire retardants or fireproofing. Ferrous cable trays expand with the increasing heat from accidental fire. This has been proven by the German Otto-Graf-Institut Test Report III.1-80999/Tei/tei "Supplementary Test On The Topic Of Mechanical Force Acting On Cable...

  5. Right-to-left shunt - Wikipedia

    en.wikipedia.org/wiki/Right-to-left_shunt
    • Causes
    • Symptoms
    • Diagnosis
    • Shunt Equation

    Congenital defects can lead to right-to-left shunting immediately after birth: 1. Persistent truncus arteriosus(minimal cyanosis) 2. Transposition of great vessels 3. Tricuspid atresia 4. Tetralogy of Fallot 5. Total anomalous pulmonary venous return A mnemonic to remember the conditions associated with right-to-left shunting involves the numbers 1-5, as follows: 1. 1 Combination Vessel: Persistent truncus arteriosus(minimal cyanosis) 2. 2 Vessels involved: Transposition of great vessels 3. 3 Leaflets: Tricuspid atresia 4. 4 Tetra- prefix: Tetralogy of Fallot 5. 5 Words: Total anomalous pulmonary venous return A mainstem intubation with an endotracheal tube can lead to right-to-left shunting.[citation needed] This occurs when the tip of the endotracheal tube is placed beyond the carina. In this way only one lung is oxygenated and oxygen-poor blood from the non-ventilated lung dilutes the oxygen level of blood returning from the lungs in the left ventricle.

    Early cyanosis is a symptom of a right-to-left shunt. A right-to-left shunt results in decreased blood flow through the pulmonary system, leading to decreased blood oxygen levels (hypoxemia). Hypoxemia manifests as cyanosis, causing "blue babies."

    Differentiation between a right-to-left shunt and pulmonary disease is often aided clinically by the results of a hyperoxia test.[citation needed]Using high levels of inspired oxygen should have little effect on the dissolved O2 in the blood because highly oxygenated blood is diluted by shunted (low oxygenation) blood.

    Q s / Q t = ( C c O 2 − C a O 2 ) / ( C c O 2 − C v O 2 ) {\\displaystyle Q_{s}/Q_{t}=(CcO_{2}-CaO_{2})/(CcO_{2}-CvO_{2})} 1. Qs/Qt is the shunt fraction 2. CcO2 is the end-capillary oxygen content 3. CaO2 is the arterial oxygen content 4. CvO2 is the mixed venous oxygen content.

  6. Silica gel - Wikipedia

    en.wikipedia.org/wiki/Silica_gel
    • History
    • Types
    • Properties
    • Regeneration
    • Preparation
    • Uses
    • Hazards
    • External Links

    Silica gel was in existence as early as the 1640s as a scientific curiosity. It was used in World War I for the adsorption of vapors and gases in gas mask canisters. The synthetic route for producing silica gel was patented by chemistry professor Walter A. Patrick at Johns Hopkins Universityin 1918. In World War II, silica gel was indispensable in the war effort for keeping penicillin dry, protecting military equipment from moisture damage,[citation needed] as a fluid cracking catalyst for the production of high octane gasoline, and as a catalyst support for the manufacture of butadiene from ethanol (feedstock for synthetic rubberproduction).

    Silica alumina gel - light yellow, chemically stable, flame-resistant, insoluble except in alkali or hydrofluoric acid. Superficial polarity, thermal stability, performance greater than fine-pored silica gel. Stabilizing silica gel - non-crystalline micro-porous solid powder, nontoxic, flame-resisting, used in brewery of grains for beer to improve taste, clearness, color and foam, removal of non-micro-organism impurities.

    Silica gel's high specific surface area (around 750–800 m2/g) allows it to adsorb water readily, making it useful as a desiccant (drying agent). Silica gel is often described as "absorbing" moisture, which may be appropriate when the gel's microscopic structure is ignored, as in silica gel packs or other products. However, material silica gel removes moisture by adsorption onto the surface of its numerous pores rather than by absorptioninto the bulk of the gel.

    Once saturated with water, the gel can be regenerated by heating it to 120 °C (250 °F) for 1–2 hours.[additional citation(s) needed]Some types of silica gel will "pop" when exposed to enough water. This is caused by breakage of the silica spheres when contacting the water.

    An aqueous solution of sodium silicate is acidified to produce a gelatinous precipitate that is washed, then dehydrated to produce colorless silica gel. When a visible indication of the moisture content of the silica gel is required, ammonium tetrachlorocobaltate(II) (NH4)2CoCl4 or cobalt chloride CoCl2 is added. This will cause the gel to be blue when dry and pink when hydrated. Due to the connection between cancer and cobalt chloride, it has been forbidden in Europe on silica gel. An alternative indicator is methyl violetwhich is orange when dry and green when hydrated.

    Desiccant

    In many items, moisture encourages the growth of mold and spoilage. Condensation may also damage other items like electronics and may speed the decomposition of chemicals, such as those in vitamin pills. Through the inclusion of silica gel packets, these items can be preserved longer. Silica gel may also be used to keep the relative humidity inside a high frequency radio or satellite transmission system waveguide as low as possible (see also humidity buffering). Excessive moisture buildup wit...

    Chemistry

    In chemistry, silica gel is used in chromatography as a stationary phase. In column chromatography, the stationary phase is most often composed of silica gel particles of 40–63 μm. Different particle sizes are used for different kinds of column chromatography as the particle size is related to surface area. The differences in particle size dictate if the silica gel should be used for flash or gravity chromatography. In this application, due to silica gel's polarity, non-polar components tend...

    Cat litter

    Silica gel is also used as cat litter, by itself or in combination with more traditional materials, such as clays including bentonite. It is non-tracking and virtually odorless.

    Silica gel is non-toxic, non-flammable, and non-reactive and stable with ordinary usage. It will react with hydrogen fluoride, fluorine, oxygen difluoride, chlorine trifluoride, strong acids, strong bases, and oxidizers. Silica gel is irritating to the respiratory tract and may cause irritation of the digestive tract, and dust from the beads may cause irritation to the skin and eyes, so precautions should be taken. Crystalline silica dust can cause silicosis, but synthetic amorphous silica gel is indurated so does not cause silicosis. Additional hazards may occur when doped with a humidity indicator.

  7. Coagulase - Wikipedia

    en.wikipedia.org/wiki/Coagulase

    Coagulase is a protein enzyme produced by several microorganisms that enables the conversion of fibrinogen to fibrin.In the laboratory, it is used to distinguish between different types of Staphylococcus isolates. Importantly, S. aureus is ...

  8. Thickening agent - Wikipedia

    en.wikipedia.org/wiki/Thickening_agent
    • Types
    • Mechanical and Thixotropic Agents
    • Cosmetics
    • Paint and Printing Thickeners
    • Petrochemistry
    • Explosives and Incendiaries

    Food thickeners frequently are based on either polysaccharides (starches, vegetable gums, and pectin), or proteins. A flavorless powdered starch used for this purpose is a fecula (from the Latin faecula, diminutive of faex, "dregs"). This category includes starches as arrowroot, cornstarch, katakuri starch, potato starch, sago, wheat flour, almond flour, tapioca and their starch derivatives. Other sugar polymers include vegetable gums such as pectin from Citrus peel, guar gum from the guar bean, and locust bean gum from the carob bean. Agar, alginin and carrageenan are polysaccharides extracted from algae. Xanthan gum is a polysaccharide secreted by the bacterium Xanthomonas campestris and carboxymethyl cellulose is a synthetic gum derived from cellulose. Proteins used as food thickeners include collagen, egg whites, and gelatin. Other thickening agents act on the proteins already present in a food. One example is sodium pyrophosphate, which acts on casein in milk during the prepara...

    Fumed silica and similar products form stiff microscopic chains or fibers which interlock or agglomerate into a mass, holding the associated liquid by surface tension, but which can separate or slide when sufficient force is applied. This causes the thixotropic or shear-thinning property (also frequently exhibited by gels), where the viscosity is non-Newtonian and becomes lower as the shearing force or time increases; their usefulness is primarily that the resulting increase in viscosity is large compared to the quantity of silica added. Fumed silica is generally accepted as safe as a food additive and is frequently used in cosmetics. Additives such as precipitated silica, fine talc, or chalk also meet the definition of thickening agent in that they increase viscosity and body while not affecting the target property of a mixture.[citation needed]

    Thickening agents used in cosmetics or personal hygiene products include viscous liquids such as polyethylene glycol, synthetic polymers such as carbomer (a trade name for polyacrylic acid) and vegetable gums. Some thickening agents may also function as stabilizers when they are used to maintain the stability of an emulsion. Some emollients, such as petroleum jelly and various waxes may also function as thickening agents in an emulsion.[citation needed]

    One of the main use of thickeners is in the paint and printing industries, which depend heavily on rheology modifiers, to prevent pigments settling to the bottom of the can, yielding inconsistent results. Water based formulas would be nearly impossible with the exception of India ink and the few other water-soluble pigments, but these would have very little coverage and at best would stain wood slightly. All modern paints and inks will have some pigment added at the factory for opacity and to control the specularity of the finish, from matte to high gloss, dependent on thickener used, but more so on the size of the particles added as opacity modifier. Particle sizes of 1 µm and below will be the limit of high gloss, probably confined to luxury automotive coatings, and about 100 µm particulates will make a bumpy surface on the microscopic scale, which scatters light and makes the surface appear matte.[citation needed] Rheology modifiers in common use: 1. Polyurethanes, acrylic polyme...

    In petrochemistry, gelling agents, also called solidifiers, are chemicals capable of reacting with oil spills and forming rubber-like solids.The gelled coagulated oil then can be removed from the water surface by skimming, suction devices, or nets. Calm or only moderately rough sea is required.

    Various materials are used to convert liquid explosives to a gel form. Nitrocellulose and other nitro esters are often used. Other possibilities include nitrated guar gum. Many fuels used in incendiary devices require thickening for increased performance. Aluminium salts of fatty acids are frequently used. Some formulations (e.g. Napalm-B) use polymeric thickeners, namely polystyrene. Hydroxyl aluminium bis(2-ethylhexanoate) is also used. Thickened pyrophoric agent, a pyrophoric replacement of napalm, is a triethylaluminium thickened with polyisobutylene.

  9. UTAC Group - Wikipedia

    en.wikipedia.org/wiki/UTAC_Group

    UTAC Group. United Test and Assembly Center Ltd ( Abbreviation: UTAC; Chinese: 联合科技; pinyin: Liánhé Kējì) is one of the largest providers of test and assembly services for a wide range of semiconductor devices, including memory, ...

  10. Benzoyl peroxide - Wikipedia

    en.wikipedia.org/wiki/Benzoyl_peroxide
    • History
    • Medical Uses
    • Non-Medical Uses
    • Safety
    • Reactivity
    • External Links

    Benzoyl peroxide was first prepared and described by Liebig in 1858.It was the first organic peroxide prepared intentionally. In 1901, J. H. Kastle and his graduate student A. S. Loevenhart observed that the compound made the tincture of guaiacum tincture turn blue, a sign of oxygen being released. Around 1905, Loevenhart reported on the successful use of BPO to treat various skin conditions, including burns, chronic varicose leg tumors, and tinea sycosis. He also reported animal experiments that showed the relatively low toxicity of the compound. Treatment with benzoyl peroxide was proposed for wounds by Lyon and Reynolds in 1929, and for sycosis vulgaris and acne varioliformis by Peck and Chagrin in 1934. However, preparations were often of questionable quality.It was officially approved for the treatment of acne in the US in 1960.

    Acne treatment

    Benzoyl peroxide is effective for treating acne lesions. It does not induce antibiotic resistance. It may be combined with salicylic acid, sulfur, erythromycin or clindamycin (antibiotics), or adapalene (a synthetic retinoid). Two common combination drugs include benzoyl peroxide/clindamycin and adapalene/benzoyl peroxide, an unusual formulation considering most retinoids are deactivated by peroxides[citation needed]. Combination products such as benzoyl peroxide/clindamycin and benzoyl perox...

    Other medical uses

    Benzoyl peroxide is used in dentistry as a tooth whiteningproduct.

    Benzoyl peroxide is one of the most important organic peroxides in terms of applications and the scale of its production. It is often used as a convenient oxidant in organic chemistry.[citation needed]

    Explosion hazard

    Concentrated benzoyl peroxide is potentially explosive like other organic peroxides, and can cause fires without external ignition. The hazard is acute for the pure material, so the compound is generally used as a solution or a paste. For example, cosmetics contain only a small percentage of benzoyl peroxide and pose no explosion risk.

    Toxicity

    Benzoyl peroxide breaks down in contact with skin, producing benzoic acidand oxygen, neither of which is very toxic. The carcinogenic potential of benzoyl peroxide has been investigated. A 1981 study published in the journal Science found that although benzoyl peroxide is not a carcinogen, it does promote cell growth when applied to an initiated tumor. The study concluded, "caution should be recommended in the use of this and other free radical-generating compounds". A 1999 IARC review of car...

    Skin irritation

    In a 1977 study using a human maximization test, 76% of subjects acquired a contact sensitization to benzoyl peroxide. Formulations of 5% and 10% were used. The U.S. National Institute for Occupational Safety and Healthhas developed criteria for a recommended standard for occupational exposure to benzoyl peroxide.

    The original 1858 synthesis by Liebig reacted benzoyl chloride with barium peroxide,a reaction that probably follows this equation: 1. 2 C6H5C(O)Cl + BaO2 → (C6H5CO)2O2 + BaCl2 Benzoyl peroxide is usually prepared by treating hydrogen peroxide with benzoyl chloride under alkaline conditions. 1. 2 C6H5COCl + H2O2 + 2 NaOH → (C6H5CO)2O2 + 2 NaCl + 2 H2O The oxygen–oxygen bond in peroxides is weak. Thus, benzoyl peroxide readily undergoes homolysis (symmetrical fission), forming free radicals: 1. (C6H5CO)2O2 → 2 C6H5CO• 2 The symbol • indicates that the products are radicals; i.e., they contain at least one unpaired electron. Such species are highly reactive. The homolysis is usually induced by heating. The half-lifeof benzoyl peroxide is one hour at 92 °C. At 131 °C, the half-life is one minute.

    NIOSH Pocket Guide to Chemical Hazards. "#0052". National Institute for Occupational Safety and Health(NIOSH).
    SIDS Initial Assessment Report from the Organisation for Economic Co-operation and Development(OECD)
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