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Reagent Chemicals
Reagent Chemicals is a publication of the American Chemical Society (ACS) Committee on Analytical Reagents, detailing standards of purity for over four hundred of the most widely used chemicals in laboratory analyses and chemical research. Chemicals that meet this standard may be sold as “ACS Reagent Grade” materials. Reagent standards relieve chemists of concern over chemical purity. “ACS Reagent Grade,” is regarded as a gold standard measure and is in some cases required for use in chemical manufacturing, usually where stringent quality specifications and a purity of equal to or greater than 95% are required. The American Chemical Society does not validate the purity of chemicals sold with this designation, but it relies on suppliers, acting in their self-interest, to meet these standards. In practice, the reliability of supplier stated purity is at times questionable. In addition to specifications for each chemical, Reagent Chemicals provides detailed methods for deter ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
American Chemical Society
The American Chemical Society (ACS) is a scientific society based in the United States that supports scientific inquiry in the field of chemistry. Founded in 1876 at New York University, the ACS currently has more than 155,000 members at all degree levels and in all fields of chemistry, chemical engineering, and related fields. It is one of the world's largest scientific societies by membership. The ACS is a 501(c)(3) non-profit organization and holds a congressional charter under Title 36 of the United States Code. Its headquarters are located in Washington, D.C., and it has a large concentration of staff in Columbus, Ohio. The ACS is a leading source of scientific information through its peer-reviewed scientific journals, national conferences, and the Chemical Abstracts Service. Its publications division produces over 60 scholarly journals including the prestigious ''Journal of the American Chemical Society'', as well as the weekly trade magazine '' Chemical & Engineeri ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
United States Environmental Protection Agency
The Environmental Protection Agency (EPA) is an independent executive agency of the United States federal government tasked with environmental protection matters. President Richard Nixon proposed the establishment of EPA on July 9, 1970; it began operation on December 2, 1970, after Nixon signed an executive order. The order establishing the EPA was ratified by committee hearings in the House and Senate. The agency is led by its administrator, who is appointed by the president and approved by the Senate. The current administrator is Michael S. Regan. The EPA is not a Cabinet department, but the administrator is normally given cabinet rank. The EPA has its headquarters in Washington, D.C., regional offices for each of the agency's ten regions and 27 laboratories. The agency conducts environmental assessment, research, and education. It has the responsibility of maintaining and enforcing national standards under a variety of environmental laws, in consultation with state, ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
United States Geological Survey
The United States Geological Survey (USGS), formerly simply known as the Geological Survey, is a scientific agency of the United States government. The scientists of the USGS study the landscape of the United States, its natural resources, and the natural hazards that threaten it. The organization's work spans the disciplines of biology, geography, geology, and hydrology. The USGS is a fact-finding research organization with no regulatory responsibility. The agency was founded on March 3, 1879. The USGS is a bureau of the United States Department of the Interior; it is that department's sole scientific agency. The USGS employs approximately 8,670 people and is headquartered in Reston, Virginia. The USGS also has major offices near Lakewood, Colorado, at the Denver Federal Center, and Menlo Park, California. The current motto of the USGS, in use since August 1997, is "science for a changing world". The agency's previous slogan, adopted on the occasion of its hundredth an ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
National Institute Of Standards And Technology
The National Institute of Standards and Technology (NIST) is an agency of the United States Department of Commerce whose mission is to promote American innovation and industrial competitiveness. NIST's activities are organized into Outline of physical science, physical science laboratory programs that include Nanotechnology, nanoscale science and technology, engineering, information technology, neutron research, material measurement, and physical measurement. From 1901 to 1988, the agency was named the National Bureau of Standards. History Background The Articles of Confederation, ratified by the colonies in 1781, provided: The United States in Congress assembled shall also have the sole and exclusive right and power of regulating the alloy and value of coin struck by their own authority, or by that of the respective states—fixing the standards of weights and measures throughout the United States. Article 1, section 8, of the Constitution of the United States, ratified in ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Academy
An academy (Attic Greek: Ἀκαδήμεια; Koine Greek Ἀκαδημία) is an institution of secondary or tertiary higher learning (and generally also research or honorary membership). The name traces back to Plato's school of philosophy, founded approximately 385 BC at Akademia, a sanctuary of Athena, the goddess of wisdom and skill, north of Athens, Greece. Etymology The word comes from the ''Academy'' in ancient Greece, which derives from the Athenian hero, ''Akademos''. Outside the city walls of Athens, the gymnasium was made famous by Plato as a center of learning. The sacred space, dedicated to the goddess of wisdom, Athena, had formerly been an olive grove, hence the expression "the groves of Academe". In these gardens, the philosopher Plato conversed with followers. Plato developed his sessions into a method of teaching philosophy and in 387 BC, established what is known today as the Old Academy. By extension, ''academia'' has come to mean the ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Inductively Coupled Plasma Atomic Emission Spectroscopy
Inductively coupled plasma atomic emission spectroscopy (ICP-AES), also referred to as inductively coupled plasma optical emission spectroscopy (ICP-OES), is an analytical technique used for the detection of chemical elements. It is a type of emission spectroscopy that uses the inductively coupled plasma to produce excited atoms and ions that emit electromagnetic radiation at wavelengths characteristic of a particular element. The plasma is a high temperature source of ionised source gas (often argon). The plasma is sustained and maintained by inductive coupling from cooled electrical coils at megahertz frequencies. The source temperature is in the range from 6000 to 10,000 K. The intensity of the emissions from various wavelengths of light are proportional to the concentrations of the elements within the sample. Mechanism The ICP-AES is composed of two parts: the ICP and the optical spectrometer. The ICP torch consists of 3 concentric quartz glass tubes. The output or "work" co ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Heavy Metals
upright=1.2, Crystals of lead.html" ;"title="osmium, a heavy metal nearly twice as dense as lead">osmium, a heavy metal nearly twice as dense as lead Heavy metals are generally defined as metals with relatively high density, densities, atomic weights, or atomic numbers. The criteria used, and whether metalloids are included, vary depending on the author and context. In metallurgy, for example, a heavy metal may be defined on the basis of density, whereas in physics the distinguishing criterion might be atomic number, while a chemist would likely be more concerned with chemical property, chemical behaviour. More specific definitions have been published, but none of these have been widely accepted. The definitions surveyed in this article encompass up to 96 out of the 118 known chemical elements; only mercury, lead and bismuth meet all of them. Despite this lack of agreement, the term (plural or singular) is widely used in science. A density of more than 5 g/cm3 is som ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Standards Organization
A standards organization, standards body, standards developing organization (SDO), or standards setting organization (SSO) is an organization whose primary function is developing, coordinating, promulgating, revising, amending, reissuing, interpreting, or otherwise contributing to the usefulness of technical standards to those who employ them. Such an organization works to create uniformity across producers, consumers, government agencies, and other relevant parties regarding terminology, product specifications (e.g. size, including units of measure), protocols, and more. Its goals could include ensuring that Company A's external hard drive works on Company B's computer, an individual's blood pressure measures the same with Company C's sphygmomanometer as it does with Company D's, or that all shirts that should not be ironed have the same icon (a clothes iron crossed out with an X) on the label. Most standards are voluntary in the sense that they are offered for adoption by people ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Geological Survey
A geological survey is the systematic investigation of the geology beneath a given piece of ground for the purpose of creating a geological map or model. Geological surveying employs techniques from the traditional walk-over survey, studying outcrops and landforms, to intrusive methods, such as hand augering and machine-driven boreholes, to the use of geophysical techniques and remote sensing methods, such as aerial photography and satellite imagery. Such surveys may be undertaken by state, province, or national geological survey organizations to maintain the geological inventory and advance the knowledge of geosciences for the benefit of the nation. A geological survey map typically superimposes the surveyed extent and boundaries of geological units on a topographic map, together with information at points (such as measurements of orientation of bedding planes) and lines (such as the intersection of faults with the land surface). The maps and reports created by geological sur ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
William Francis Hillebrand
William Francis Hillebrand (December 12, 1853 – February 7, 1925) was an American chemist. Biography He was the son of the renowned botanist William Hillebrand. He studied at Cornell University and then in Germany at the University of Heidelberg where he received his Ph.D. in 1875. He then worked with Robert Bunsen for two semesters. His research on metallic cerium, which he together with Thomas Norton obtained first in 1872, started his academic career. He studied organic chemistry for three semesters with Wilhelm Rudolph Fittig at the University of Strasbourg, but changed to geochemistry and metallurgy by studying at the Freiberg Mining Academy. After returning home to the United States in 1878, he opened an assay office in Leadville, Colorado, in 1879, and then started working as a chemist at the United States Geological Survey in 1880. That year he was sent to Denver to establish a chemical laboratory for the Rocky Mountain Division of the Survey. For five years he remained ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Paywall
A paywall is a method of restricting access to content, with a purchase or a paid subscription, especially news. Beginning in the mid-2010s, newspapers started implementing paywalls on their websites as a way to increase revenue after years of decline in paid print readership and advertising revenue, partly due to the use of ad blockers. In academics, research papers are often subject to a paywall and are available via academic libraries that subscribe. Paywalls have also been used as a way of increasing the number of print subscribers; for example, some newspapers offer access to online content plus delivery of a Sunday print edition at a lower price than online access alone. Newspaper websites such as that of '' The Boston Globe'' and ''The New York Times'' use this tactic because it increases both their online revenue and their print circulation (which in turn provides more ad revenue). History In 1996, ''The Wall Street Journal'' set up and has continued to maintain ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Electronic Journal
An academic journal or scholarly journal is a periodical publication in which scholarship relating to a particular academic discipline is published. Academic journals serve as permanent and transparent forums for the presentation, scrutiny, and discussion of research. They nearly-universally require peer-review or other scrutiny from contemporaries competent and established in their respective fields. Content typically takes the form of articles presenting original research, review articles, or book reviews. The purpose of an academic journal, according to Henry Oldenburg (the first editor of '' Philosophical Transactions of the Royal Society''), is to give researchers a venue to "impart their knowledge to one another, and contribute what they can to the Grand design of improving natural knowledge, and perfecting all Philosophical Arts, and Sciences." The term ''academic journal'' applies to scholarly publications in all fields; this article discusses the aspects common to al ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
