Big Chemical Encyclopedia

Chemical substances, components, reactions, process design ...

Articles Figures Tables About

Tools available

Classification Societies exist to promote the safe construction of ships and to protect that condition throughout the life of the vessel. One of the tools available to shipbuilders, shipowners and surveyors that can be used to achieve these aims is Non-Destructive Examination (NDE). The intent of this presentation is to describe the application of NDE to hull structure during construction and also during periodic surveys as seen from the viewpoint of the Classification Surveyor. [Pg.1041]

Surfaces are investigated with surface-sensitive teclmiques in order to elucidate fiindamental infonnation. The approach most often used is to employ a variety of techniques to investigate a particular materials system. As each teclmique provides only a limited amount of infonnation, results from many teclmiques must be correlated in order to obtain a comprehensive understanding of surface properties. In section A 1.7.5. methods for the experimental analysis of surfaces in vacuum are outlined. Note that the interactions of various kinds of particles with surfaces are a critical component of these teclmiques. In addition, one of the more mteresting aspects of surface science is to use the tools available, such as electron, ion or laser beams, or even the tip of a scaiming probe instrument, to modify a surface at the atomic scale. The physics of the interactions of particles with surfaces and the kinds of modifications that can be made to surfaces are an integral part of this section. [Pg.284]

To identify the main methods and tools available for the computer prediction of spectra from the molecular structure, and for automatic structure elucidation from spectral data... [Pg.515]

The group that has the most difficulty finding appropriate literature are working chemists, not theorists. These are experienced researchers who know chemistry and now have computational tools available. These are people who want to use computational chemistry to address real-world research problems and are bound to run into significant difficulties. This book is for those chemists. [Pg.396]

Although their presentiy accepted stmctures were unknown, they were characterized with the tools available at the time. Because morphine (2, R = H), C22H22NO 3, was shown to have properties similar to the basic soluble salts obtained from the ashes of plants (alkah) it was categorized as a vegetable alkaU or alkaloid, and it is generally accepted that it was for this case the word was coined. [Pg.529]

Statistical analysis can range from relatively simple regression analysis to complex input/output and mathematical models. The advent of the computer and its accessibiUty in most companies has broadened the tools a researcher has to manipulate data. However, the results are only as good as the inputs. Most veteran market researchers accept the statistical tools available to them but use the results to implement their judgment rather than uncritically accepting the machine output. [Pg.535]

The most promising approach to laboratory techniques for predicting performance is to understand the mechanism of failure and then use iastmmental methods to study the susceptibiUty of a coating to failure. The most powerful tool available now is the use of esr spectrometry to monitor the rate of free-radical appearance and disappearance (117—119) (see Magnetic spin resonance). [Pg.349]

An extensive survey of accelerated test methods for anticorrosive coating performance which emphasizes the need to develop more meaningful methods of testing has been pubUshed (129). The most powerful tool available is the accumulated material in data banks correlating substrate, composition, apphcation conditions, and specifics of exposure environments with performance. [Pg.350]

Chemical incompatibility charts can help in organizing available data on the incompatibilities existing between expected mixtures. Frurip (Frurip et ah, 1997) gives one procedure for developing a chemical compatibility chart while describing some of the tools available. CCPS G-13 also provides a table of known incompatibility hazards. [Pg.22]

Probably the least appreciated weakness of QRA is that the results are difficult to duplicate by independent experts. Even with the variety of sophisticated tools available for use, QRA is still largely dependent on good engineering judgment. The subtle assumptions of analysts performing QRA studies can often be the driving force behind the results. Many times these assumptions are at best arguable, and at worst arbitrary. [Pg.48]

The tools available for site selection include climatological data, topography, population data, emission inventory data, and diffusion modeling. Climatological data are useful in relating meteorology to emission patterns. For example, elevated levels of photochemical oxidant are generally related... [Pg.217]

A final tool available is the vendor s ability to generate a set of off-design curves. By performing a stage-by-stage analysis of the proposed test gas, correlations are much easier to make. This is probably best illustrated by an example reported by Wong (9). [Pg.426]

Today there are many tools available to aid in problem solving or f ure analysis. These include the Weibull Analysis, Failure Mode i Effect Analysis, and Fault Tree Analysis, to name a few. One of the m widely accepted is the Weibull analysis. This method can provide accurate engineering analysis based on extraordinary small samples [1]. [Pg.467]

There is work to be done to improve the tools available for the application of inherently safer concepts. Chapter 8 discusses some opportunities for future research. [Pg.5]

Three major themes have been emphasized in this chapter. The first is that an effective data collection system is one of the most powerful tools available to minimize human error. Second, data collection systems must adequately address underlying causes. Merely tabulating accidents in terms of their surface similarities, or using inadequate causal descriptions such as "process worker failed to follow procedures" is not sufficient to develop effective remedial strategies. Finally, a successful data collection and incident investigation system requires an enlightened, systems oriented view of human error to be held by management, and participation and commitment from the workforce. [Pg.291]

There is a large array of Quality Management tools available to help build new systems. The most commonly used tools are described in the following paragraphs. The tools you actually use may be determined by the Quality Management process that is in place in your organization it is important... [Pg.100]

By measuring the L-isoleucine/o-alloisoleucine ratio in the protein isolated from the eggshells of an extinct Australian bird, a team of scientists recently determined that this bird lived approximately 50,000 years ago. Radiocarbon ( " C) dating is not accurate for samples older than about 35,000 years, so AAR is a useful addition to the tools available to paleontologists. [Pg.1116]

In general, when a pharmacological constant or parameter is measured it should be done so repeatedly to give a measure of confidence in the value obtained (i.e., the likelihood that if the measurement were repeated it would yield the same value). There are various statistical tools available to determine this. An important tool and concept in this regard is the Gaussian distribution. [Pg.225]

Electronic product catalog Electronic Product Catalog is a sales tool available to material producers and distributors. Potential customers looking for materials can be directed to a website through direct links from datasheets accessed by customers on Prospector Web. [Pg.593]

X-Ray diffraction from single crystals is the most direct and powerful experimental tool available to determine molecular structures and intermolecular interactions at atomic resolution. Monochromatic CuKa radiation of wavelength (X) 1.5418 A is commonly used to collect the X-ray intensities diffracted by the electrons in the crystal. The structure amplitudes, whose squares are the intensities of the reflections, coupled with their appropriate phases, are the basic ingredients to locate atomic positions. Because phases cannot be experimentally recorded, the phase problem has to be resolved by one of the well-known techniques the heavy-atom method, the direct method, anomalous dispersion, and isomorphous replacement.1 Once approximate phases of some strong reflections are obtained, the electron-density maps computed by Fourier summation, which requires both amplitudes and phases, lead to a partial solution of the crystal structure. Phases based on this initial structure can be used to include previously omitted reflections so that in a couple of trials, the entire structure is traced at a high resolution. Difference Fourier maps at this stage are helpful to locate ions and solvent molecules. Subsequent refinement of the crystal structure by well-known least-squares methods ensures reliable atomic coordinates and thermal parameters. [Pg.312]

When trying to understand and to manipulate matter and materials, chemistry does not start by looking at the natural world in all its complexity. Rather, it seeks to establish what have been termed exemplar phenomena ideal or simplified examples that are capable of investigation with the tools available at the time (Gilbert, Borrlter, Elmer, 2000). This level consists of representatiorrs of the empirical properties of solids, liquids (taken to include solutions, especially aqueous solutiorts), colloids, gases and aerosols. These properties are perceptible in chemistry laboratories and in everyday life and are therefore able to be meastrred. Examples of such properties are mass, density, concentration, pH, temperatrrre and osmotic presstrre. [Pg.5]

As any home owner knows, no water faucet or valve is maintenance free. A laboratory operator should for that reason have repair parts and proper tools available at all times. [Pg.88]

Where are quality tools available Laboratory supply houses sell handy tool kits for normal repair and maintenance jobs. They may come in compaifmented boxes or pouches that are easy to carry to where they are to be used. Such organization also makes it simple to spot a tool left behind on a job. Unfortunately, kits are often quite expensive and may contain some tools that will never be needed, or they may lack tools required in a certain laboratory. In such cases, tools are best obtained separately from hardware... [Pg.132]

There are many nonintrusive experimental tools available that can help scientists to develop a good picture of fluid dynamics and transport in chemical reactors. Laser Doppler velocimetry (LDV), particle image velocimetry (PIV) and sonar Doppler for velocity measurement, planar laser induced fluorescence (PLIF) for mixing studies, and high-speed cameras and tomography are very useful for multiphase studies. These experimental methods combined with computational fluid dynamics (CFDs) provide very good tools to understand what is happening in chemical reactors. [Pg.331]

In a tiny fraction of cases, a quick formula can be used. For most cases, the analysis uses an options tree, with one leaf per possible outcome. However, this falls prey to the curse of dimensionality —the number of leaves on the tree grows exponentially in the number of risk and decision dimensions considered. Thus only a limited, simple set of situations can be optimized in this way because one has to severely limit the decisions and risks that are considered. Tools available to help automate and simplify options analysis, widely used in pharmaceutical project evaluation, include Excel addons such as R1SK [11] and more graphically based solutions such as DPL [12]. Both of these support the creation and evaluation of decision trees and of influence diagrams Figure 11.2 shows a simple example of each of these. A primer in applied decision theory is Clemen s book Making Hard Decisions, other sources may be found in the website of James Vornov, Director of Clinical Research at Guildford Pharmaceuticals, a recent convert to decision theory for options analysis [13]. [Pg.254]

With the development of HPLC, a new dimension was added to the tools available for the study of natural products. HPLC is ideally suited to the analysis of non-volatile, sensitive compounds frequently found in biological systems. Unlike other available separation techniques such as TLC and electrophoresis, HPLC methods provide both qualitative and quantitative data and can be easily automated. The basis for the HPLC method for the PSP toxins was established in the late 1970 s when Buckley et al. (2) reported the post-column derivatization of the PSP toxins based on an alkaline oxidation reaction described by Bates and Rapoport (3). Based on this foundation, a series of investigations were conducted to develop a rapid, efficient HPLC method to detect the multiple toxins involved in PSP. Originally, a variety of silica-based, bonded stationary phases were utilized with a low-pressure post-column reaction system (PCRS) (4,5), Later, with improvements in toxin separation mechanisms and the utilization of a high efficiency PCRS, a... [Pg.66]

It may be possible to achieve an adequate solution of these problems by developing catalysts with snrface properties that have been tailored deliberately so as to provide a favorable catalytic action on all intermediate steps that need it. Such catalysts should be polyfunctional and exhibit a certain degree of chemical and structural surface microheterogeneity. Electrochemical nanoelectrochemistry (see Chapter 36) may be a possible approach for synthesizing snch snrfaces. For a detailed investigation and control of these catalytic surfaces, the tools available among the experimental physical methods (see Chapter 27) will be nsefnl. [Pg.553]


See other pages where Tools available is mentioned: [Pg.946]    [Pg.629]    [Pg.175]    [Pg.451]    [Pg.110]    [Pg.426]    [Pg.2420]    [Pg.31]    [Pg.405]    [Pg.268]    [Pg.1105]    [Pg.118]    [Pg.812]    [Pg.101]    [Pg.826]    [Pg.236]    [Pg.182]    [Pg.66]    [Pg.107]    [Pg.241]    [Pg.304]    [Pg.156]    [Pg.116]    [Pg.268]   
See also in sourсe #XX -- [ Pg.278 ]




SEARCH



Available Tools and Protocols

Chemical evolution available tools

Choices, available tools

Freely and Commercially Available Tools for the Study of P450 in Brain

Online tools available

© 2024 chempedia.info