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Scientific study

Some scientific studies indicate that the gam in performance obtained through the use of anabolic steroids is small This may be a case though in which the anecdotal evidence of the athletes may be closer to the mark than the scientific studies The scientific studies are done under ethical conditions in which patients are treated with prescription level doses of steroids A 240 pound offensive tackle ( too small by todays standards) may take several ana bolic steroids at a time at 10-20 times their pre scribed doses in order to weigh the 280 pounds he (or his coach) feels is necessary The price athletes pay for gams in size and strength can be enormous This price includes emotional costs (friendships lost because of heightened aggressiveness) sterility testicular atro phy (the testes cease to function once the body starts to obtain a sufficient supply of testosterone like steroids from outside) and increased risk of prema ture death from liver cancer or heart disease... [Pg.1099]

More recently, studies of wine and beer have initiated techniques of statistically vaUd sensory analysis. Scientific studies involving wine continue in these areas, building on past discoveries. Natural phenols as desirable dietary components and monitors of storage and aging reactions are currently active fields. Viticultural research, as well as enological, continues to improve grapes and the wines made from them (11). [Pg.366]

Early scientific studies were ptedominandy aimed at objects often referred to as belonging to the fine arts. Subsequendy, equal importance and effort has been attached to studies of objects of cultural and historical interest, such as archaeological and ethnographic materials, or manuscripts, documents, photographs, and books in archives andUbraries. This article is meant to be inclusive of all such objects as well as of fine arts objects. The term art object when used is an inclusive, generic connotation rather than an exclusive one. [Pg.416]

There are several possible reasons why a scientific study of an art work may be desirable. An obvious one is in cases where the authenticity of an object is doubted on styHstic grounds, but no unanimous opinion exists. The scientist can identify the materials, analy2e the chemical composition, and then investigate whether these correspond to what has been found in comparable objects of unquestioned provenance. If the sources for the materials can be characterized, eg, through trace element composition or stmcture, it may be possible to determine whether the sources involved in the procurement of the materials for comparable objects with known provenance are the same. Comparative examination of the technological processes involved in the manufacture allows for conclusions as to whether the object was made using techniques actually available to the people who supposedly created it. Additionally, dating techniques may lead to the estabUshment of the date of manufacture. [Pg.416]

For small-scale preparation of samples for scientific studies, the precursor polymer may be dissolved in xylene at 80°C, followed by addition of the cation source. A gelled fluid is normally obtained immediately, and the ionomer is recovered as a powder by chopping the gel in a large excess of acetone using a laboratory blender. [Pg.408]

MetaHurgy also embraces the scientific study of the stmcture, properties, and behavior of metals and metal aHoys. This branch of metaHurgy is referred to as physical metaHurgy. The two areas that commonly characterize physical metaHurgy are stmcture—property relationships and failure analysis. [Pg.157]

The neutrons in a research reactor can be used for many types of scientific studies, including basic physics, radiological effects, fundamental biology, analysis of trace elements, material damage, and treatment of disease. Neutrons can also be dedicated to the production of nuclear weapons materials such as plutonium-239 from uranium-238 and tritium, H, from lithium-6. Alternatively, neutrons can be used to produce radioisotopes for medical diagnosis and treatment, for gamma irradiation sources, or for heat energy sources in space. [Pg.210]

Pubhc concerns about pesticides in the diet of infants and children resulted in an expert committee convened by the U.S. National Academy of Sciences which devoted four years to the review of all available data. A consensus report was issued in 1993 (80). A number of recommendations for further work to more precisely define what constitutes the diet of infants and children were made. No risk could be estimated. The residue data reviewed by the panel were mainly from monitoring studies conducted by the PDA using multiresidue methods to analyze fresh produce and market basket samples collected from various geographic areas (81,82). These and other rehable scientific studies have demonstrated that relatively few food samples contain detectable residues. Most residues are far below estabhshed tolerances which are set above the maximum residue found in treated raw agricultural... [Pg.150]

Atmospheric Pollution in Leicester—A Scientific Study, D.S.I.R. Atmospheric Research Technical Paper No. 1. H.M. Stationery Office, London, 1945. [Pg.17]

Of course, freezing of a liquid - or its inverse - are themselves phase transformations, but the scientific study of freezing and melting was not developed until well into the 20th century (Section 9.1.1). Polymorphism also links with metastability thus aragonite, one polymorphic form of calcium carbonate, is under most circumstances metastable to the more familiar form, calcite. [Pg.99]

The scientific study of surfaces, and the full recognition of how much a surface differs from a bulk structure, awaited a drastic improvement in vacuum technique. The next Section is devoted to a brief account of the history of vacuum. [Pg.404]

McBain and Hopkins [2], in their classical scientific study, argued that the surface roughness of a porous material was the basis of mechanical adhesion , its being... [Pg.342]

The main objective of air quality guidelines and standards is the protection of human health. Since fme particulates (PM,) are more likely to cause adverse health effects than coarse particulates, guidelines and standards referring to fine particulate concentrations are preferred to those referring to TSP, which includes coarse particulate concentrations. Scientific studies provide ample evidence of the relationship between exposure to short-term and long-term ambient particulate concentrations and human mortality and morbidity effects. However, the dose-response mechanism is not yet fully understood. Furthermore, according to the WHO, there is no safe threshold level below which health damage does not occur. [Pg.19]

S. Varadarajah, Report on Scientific Studies on the Factors Related to Bhopal Toxic Gas Leakage, Indian Planning Commission, New Delhi, India, Dec. 1985. [Pg.379]

Since these PM standards were established, the EPA has reviewed peer-reviewed scientific studies that suggest that significant health effects occur at concentrations below the 1987 standards. In addition, some studies attributed adverse health effects to particles smaller than 10 microns. In July 1997, the EPA, under the National Ambient Air Quality Standards (NAAQS), added standards for particulate matter with a diameter of 2.5 microns or less (PM, ). The annual PM, 5 standard was set at 15 pg/ni and the 24-hour PMj standard was set at 65 p.g/m . [Pg.445]

The best scientific study comparing the LWD logs with the wireline logs has been done in the framework of a project sponsored by the oil and service companies in Conoco test facility, Kay County, Oklahoma in 1990. [Pg.1077]

What is the nature of scientific study What is the nature of chemistry ... [Pg.1]

Since ancient times, the light emitted by fireflies and glow-worms has attracted the curiosity of people. Descriptions of the phenomena are frequently found in old poems, songs and folklores of many countries. Old scientific studies of these phenomena are also numerous, particularly after the 17th century. However, the chemical study was not begun until the early 20th century. [Pg.1]

Until about 1880 the lead-acid battery was exclusively then subject of scientific study. Possible commercial utilization lacked suitable charging processes secondary cells had to be charged by means of the primary cells already known at that time. [Pg.251]

Although herbs have been used for thousands of years, most of what we know has been from observation. Most herbs have not been scientifically studied for safety and efficacy (effectiveness). Much of what we know about herbal therapy has come from Europe particularly Germany. During the last several decades, European scientists have studied botanical plants in ways that seek to identify how they work at the cellular level, what chemicals are most effective, and adverse effects related to their use. Germany lias compiled information on 300 herbs and made recommendations for their use. [Pg.13]

The active state of luminescence spectrometry today may be judged ly an examination of the 1988 issue of Fundamental Reviews of Analytical Chemistry (78), which divides its report titled Molecular Fluorescence, Phosphorescence, and Chemiluminescence Spectrometry into about 27 specialized topical areas, depending on how you choose to count all the subdivisions. This profusion of luminescence topics in Fundamental Reviews is just the tip of the iceberg, because it omits all publications not primarily concerned with analytical applications. Fundamental Reviews does, however, represent a good cross-section of the available techniques because nearly every method for using luminescence in scientific studies eventually finds a use in some form of chemical analysis. Since it would be impossible to mention here all of the current important applications and developments in the entire universe of luminescence, this report continues with a look at progress in a few current areas that seem significant to the author for their potential impact on future work. [Pg.11]

Scientific studies of friction can be traced back to several hundreds years ago when the pioneers, Leonardo da Vinci (1452-1519), Amontons (1699), and Coulomb (1785), established the law of friction that "friction is proportional to the normal load and independent of the nominal area of contact, which are still being taught today in schools. Since then, scientists and engineers have been trying to answer two fundamental questions where friction comes from and why it exhibits such a behavior as described above. Impressive progress has been made but the mystery of friction has not been resolved yet. In an attempt to interpret the origin of... [Pg.171]

Aerosol spray cans were invented in 1929, and perfection of a reliable valve and development of disposable cans took place in the 1940s. Shortly thereafter, aerosol became a household word. Like many other modem conveniences, however, the aerosol spray can has drawbacks as well as advantages. Because the particles in an aerosol are extremely tiny, they are quite mobile. They last for a long time in the atmosphere and can affect the climate, as already described. They can penetrate deep into our lungs and cause adverse health effects. Thus, anthropogenic aerosols have both global and local side effects. Despite increasing scientific studies, these effects are not yet fttlly understood. [Pg.873]

Recent scientific studies have clearly established the nutritional role of dietary fiber in several health conditions (Jalili et al., 2000), such as hypercholesterolemia (Topping et al., 1990), diabetes (Chandalia et al., 2000) and bowel function. It is also effective in preventing urinary stones (Ohkawa et al., 1984). The Food and Nutrition Board (Institute of Medicine Report, 2001) recommended a daily allowance for fiber of 25-30 g, though it is not an essential nutrient. Rice bran fiber offers a good source of non-bloating dietary fiber and is marketed as RiceMucil by NutraStar Company in the USA. [Pg.352]

Phytosterols have been demonstrated as being anti-cancer components in the diet (Awad and Fink 2000). Scientific studies indicate that phytosterols may offer profection against colon, breast and prostate cancers (Vanderhaeghe and Bouic, 2000). The possible mechanisms, as reported by these authors, include the effect of phytosterols on membrane structure and function and on the signal transduction pathways that regulate tumor growth and apoptosis. The rice bran derived phytosterol-cycloartenol-ferulic acid ester on the central nervous system has been studied by Hiraga et al. (1993). [Pg.360]

Although rice bran is still a wasted product all over the world, recent scientific studies have recognized its potential health benefits. This is a unique, nutrient-dense natural product which offers health benefits for a series of ailments. It is a food pharmacy worth considering not only for general health maintenance but also as a dietary supplement for serious health conditions. With the advent of unique stabilization technology rice bran, an under-utilized waste product, has now been made available as a highly nutritious, health-promoting food for humans. [Pg.370]

Alloys or multimetallic catalysts are not only commercially important but they are also an attractive object for scientific studies. In the recent past these studies helped to identify some factors which determine the activity and - mainly - the selectivity of metal catalysts (1-5). [Pg.267]

Triage is a searchable database of scientific studies on the health and environmental effects of toxic chemicals related to Section 8(e) of TSCA. [Pg.310]


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Measurement in Scientific Study

Scientific method A process of studying

Scientific method A process of studying natural phenomena that involves making

Scientific studies trials

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