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Lead Chromate
Lead(II) chromate is an inorganic compound with the chemical formula . It is a bright yellow salt that is very poorly soluble in water. It occurs also as the mineral crocoite. It is used as a pigment. Structure Two polymorphs of lead chromate are known, orthorhombic and the more stable monoclinic form. Monoclinic lead chromate is used in paints under the name chrome yellow, and many other names. Lead chromate adopts the monazite structure, meaning that the connectivity of the atoms is very similar to other compounds of the type . Pb(II) has a distorted coordination sphere being surrounded by eight oxides with Pb-O distances ranging from 2.53 to 2.80 Å. The chromate anion is tetrahedral, as usual. Unstable polymorphs of lead chromate are the greenish yellow orthorhombic form and a red-orange tetragonal form. Applications Approximately 37,000 tons were produced in 1996. The main applications are as a pigment in paints, under the name chrome yellow. Preparation Lead(II ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Nitric Acid
Nitric acid is an inorganic compound with the formula . It is a highly corrosive mineral acid. The compound is colorless, but samples tend to acquire a yellow cast over time due to decomposition into nitrogen oxide, oxides of nitrogen. Most commercially available nitric acid has a concentration of 68% in water. When the solution contains more than 86% , it is referred to as ''fuming nitric acid''. Depending on the amount of nitrogen dioxide present, fuming nitric acid is further characterized as red fuming nitric acid at concentrations above 86%, or white fuming nitric acid at concentrations above 95%. Nitric acid is the primary reagent used for nitration – the addition of a nitro group, typically to an organic molecule. While some resulting nitro compounds are shock- and thermally-sensitive explosives, a few are stable enough to be used in munitions and demolition, while others are still more stable and used as synthetic dyes and medicines (e.g. metronidazole). Nitric acid is ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Chrome Red
Chrome orange is a mixed oxide with the chemical formula Pb2CrO5. It can be made by treating a lead(II) salt with an alkaline solution of a Chromate and dichromate, chromate or by treating chrome yellow (PbCrO4) with strongly basic solution.. Synthesis and nanoparticles Pb2CrO5 can be synthesized with a Gas-liquid Chromatograph, gas-liquid precipitation process. Changing the pH controls whether PbCrO4 or Pb2CrO5 is created. Orthorhombic crystal system, Orthorhombic nanocrystals can be selectively synthesized in a facile room temperature solution for Pb2CrO5. Using a Microwave-assisted organic synthesis, microwave-assisted ionic liquid (MAIL) method, bundle and rod-like nanocrystals of Pb2CrO5 were formed. The bundles look like bundles of straw, secured in the middle. In basic solution, single-crystalline Pb2CrO5 could be formed by heating lead acetate and potassium dichromate with microwave radiation for only 10 minutes at 90 Celsius. The MAIL process is simple, fast, and does ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Centers For Disease Control And Prevention
The Centers for Disease Control and Prevention (CDC) is the National public health institutes, national public health agency of the United States. It is a Federal agencies of the United States, United States federal agency under the United States Department of Health and Human Services, Department of Health and Human Services (HHS), and is headquartered in Atlanta, Georgia. The CDC's current nominee for director is Susan Monarez. She became acting director on January 23, 2025, but stepped down on March 24, 2025 when nominated for the director position. On May 14, 2025, Robert F. Kennedy Jr. stated that lawyer Matthew Buzzelli is acting CDC director. However, the CDC web site does not state the acting director's name. The agency's main goal is the protection of public health and safety through the control and prevention of disease, injury, and disability in the US and worldwide. The CDC focuses national attention on developing and applying disease control and prevention. It e ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
United States
The United States of America (USA), also known as the United States (U.S.) or America, is a country primarily located in North America. It is a federal republic of 50 U.S. state, states and a federal capital district, Washington, D.C. The 48 contiguous states border Canada to the north and Mexico to the south, with the semi-exclave of Alaska in the northwest and the archipelago of Hawaii in the Pacific Ocean. The United States asserts sovereignty over five Territories of the United States, major island territories and United States Minor Outlying Islands, various uninhabited islands in Oceania and the Caribbean. It is a megadiverse country, with the world's List of countries and dependencies by area, third-largest land area and List of countries and dependencies by population, third-largest population, exceeding 340 million. Its three Metropolitan statistical areas by population, largest metropolitan areas are New York metropolitan area, New York, Greater Los Angeles, Los Angel ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Food And Drug Administration
The United States Food and Drug Administration (FDA or US FDA) is a List of United States federal agencies, federal agency of the United States Department of Health and Human Services, Department of Health and Human Services. The FDA is responsible for protecting and promoting public health through the control and supervision of food safety, tobacco products, caffeine products, dietary supplements, Prescription drug, prescription and Over-the-counter drug, over-the-counter pharmaceutical drugs (medications), vaccines, biopharmaceuticals, blood transfusions, medical devices, electromagnetic radiation emitting devices (ERED), cosmetics, Animal feed, animal foods & feed and Veterinary medicine, veterinary products. The FDA's primary focus is enforcement of the Federal Food, Drug, and Cosmetic Act (FD&C). However, the agency also enforces other laws, notably Section 361 of the Public Health Service Act as well as associated regulations. Much of this regulatory-enforcement work is ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cinnamon
Cinnamon is a spice obtained from the inner bark of several tree species from the genus ''Cinnamomum''. Cinnamon is used mainly as an aromatic condiment and flavouring additive in a wide variety of cuisines, sweet and savoury dishes, biscuits, breakfast cereals, Snack, snack foods, bagels, teas, hot chocolate and traditional foods. The aroma and flavour of cinnamon derive from its essential oil and principal component, cinnamaldehyde, as well as numerous other constituents, including eugenol. Cinnamon is the name for several species of trees and the commercial spice products that some of them produce. All are members of the genus ''Cinnamomum'' in the family Lauraceae. Only a few ''Cinnamomum'' species are grown commercially for spice. ''Cinnamomum verum'' (alternatively ''C. zeylanicum''), known as "Ceylon cinnamon" after its origins in Sri Lanka (formerly Ceylon), is considered to be "true cinnamon", but most cinnamon in international commerce is derived from four other speci ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Lead Paint
Lead paint or lead-based paint is paint containing lead. As pigment, lead(II) chromate (, "chrome yellow"), lead(II,IV) oxide, (, "red lead"), and lead(II) carbonate (, "white lead") are the most common forms.. Lead is added to paint to accelerate drying oil, drying, increase durability, maintain a fresh appearance, and resist moisture that causes corrosion. It is one of the main health and environmental issues with paint, environmental hazards associated with paint. Lead paint has been generally phased out of use due to the toxic nature of lead. Alternatives such as water-based, lead-free traffic paint are readily available. In some countries, lead continues to be added to paint intended for domestic use, whereas countries such as the United States and the lead-based paint in the United Kingdom, United Kingdom have regulations prohibiting its use. However, lead paint may still be found in older properties painted prior to the introduction of such regulations. Although lead has ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Turmeric
Turmeric (), or ''Curcuma longa'' (), is a flowering plant in the ginger family Zingiberaceae. It is a perennial, rhizomatous, herbaceous plant native to the Indian subcontinent and Southeast Asia that requires temperatures between and high annual rainfall to thrive. Plants are gathered each year for their rhizomes, some for propagation in the following season and some for consumption or dyeing. The rhizomes can be used fresh, but they are often boiled in water and dried, after which they are ground into a deep orange-yellow shelf-stable spice powder commonly used as a coloring and flavoring agent in many Asian cuisines, especially for curries ( curry powder). Turmeric powder has a warm, bitter, black pepper-like flavor and earthy, mustard-like aroma. Although long used in Ayurvedic medicine, there is no high-quality clinical evidence that consuming turmeric or the principal turmeric constituent, curcumin, is effective for treating any disease. Curcumin, a bright ye ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Candy
Candy, alternatively called sweets or lollies, is a Confectionery, confection that features sugar as a principal ingredient. The category, also called ''sugar confectionery'', encompasses any sweet confection, including chocolate, chewing gum, and sugar candy. Vegetables, fruit, or Nut (fruit), nuts which have been glaze (cooking technique), glazed and coated with sugar are said to be ''Candied fruit, candied''. Physically, candy is characterized by the use of a significant amount of sugar or sugar substitutes. Unlike a cake or loaf of bread that would be shared among many people, candies are usually made in smaller pieces. However, the definition of candy also depends upon how people treat the food. Unlike sweet pastries served for a dessert course at the end of a meal, candies are normally eaten casually, often with the fingers, as a snack between meals. Each culture has its own ideas of what constitutes candy rather than dessert. The same food may be a candy in one culture ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
LD50
In toxicology, the median lethal dose, LD50 (abbreviation for "lethal dose, 50%"), LC50 (lethal concentration, 50%) or LCt50 is a toxic unit that measures the lethal dose of a given substance. The value of LD50 for a substance is the dose required to kill half the members of a tested population after a specified test duration. LD50 figures are frequently used as a general indicator of a substance's acute toxicity. A lower LD50 is indicative of higher toxicity. The term LD50 is generally attributed to John William Trevan. The test was created by J. W. Trevan in 1927. The term semilethal dose is occasionally used in the same sense, in particular with translations of foreign language text, but can also refer to a sublethal dose. LD50 is usually determined by tests on animals such as laboratory mice. In 2011, the U.S. Food and Drug Administration approved alternative methods to LD50 for testing the cosmetic drug botox without animal tests. Conventions The LD50 is usually expres ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hexavalent Chromium
Hexavalent chromium (chromium(VI), Cr(VI), chromium 6) is any chemical compound that contains the element chromium in the +6 oxidation state (thus hexavalent). It has been identified as carcinogenic, which is of concern since approximately of hexavalent chromium were produced in 1985. Hexavalent chromium compounds can be carcinogens ( IARC Group 1), especially if airborne and inhaled where they can cause lung cancer. Occurrence and uses Hexavalent chromium occurs only rarely in nature, an exception being crocoite (PbCrO4). It is however produced on a large scale industrially. Virtually all chromium ore is processed via the formation of hexavalent chromium, specifically the salt sodium dichromate. Sodium chromate is converted into other hexavalent chromium compounds such as chromium trioxide and various salts of chromate and dichromate. Industrial uses of hexavalent chromium compounds include chromate pigments in dyes, paints, inks, and plastics; chromates added as anti ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
