Big Chemical Encyclopedia

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

Articles Figures Tables About

Handicapped

In effect, the ions race each other along the drift tube, but the winners are always the ions of smallest m/z value, since these have the shortest flight times. The last to arrive at the detector are always those of greatest mass, which have the longest flight times. However, as in a race, for there to be a separation at the finish line (the detector), the ions must all start from the ion source at the same time (no handicapping allowed ). [Pg.406]

Compared to photographic films, BR is handicapped due to its very low light sensitivity. Also, as a possible material for disk-shaped digital optical information storage, BR does not offer an advantage over estabUshed magnetooptical materials ia spite of its higher line resolutioa, because ia both cases... [Pg.153]

Further to this, it should be possible to better understand how odors affect human moods and performance. Studies involving autistic cluldten, severely mentally handicapped persons, and traumatic and stress-related situations where odors are being used to affect behavior may open many more doors to the understanding (4). [Pg.295]

Peclet number independent of Reynolds number also means that turbulent diffusion or dispersion is directly proportional to the fluid velocity. In general, reactors that are simple in construction, (tubular reactors and adiabatic reactors) approach their ideal condition much better in commercial size then on laboratory scale. On small scale and corresponding low flows, they are handicapped by significant temperature and concentration gradients that are not even well defined. In contrast, recycle reactors and CSTRs come much closer to their ideal state in laboratory sizes than in large equipment. The energy requirement for recycle reaci ors grows with the square of the volume. This limits increases in size or applicable recycle ratios. [Pg.59]

Accepts information on the characteristics of populations located in areas that could be in the vulnerable zone Location of special populations (e.g., elderly-handicapped prisons and schools) and population density. [Pg.273]

A major mass transit handicap is sprawling growth. Mass transit works most effectively in a hub and spoke manner, and the decentralization of urban areas makes it harder and harder to design effective mass transit. This mismatched segregation of home, work, and leisure—particularly in cities such as Houston, Atlanta, and Los Angeles— woiild require a long time to reverse. [Pg.134]

Engineers engage in professional relationships without bias because of race, religion, sex, age, national origin, or handicap. [Pg.382]

Most plants are highly dependent upon their compressed air supply and it should be assured that the air is in at least reasonable condition at all times, even if the drying system is out of use for maintenance or repair. It is possible that the line condensation would be so bad that some air applications would be handicapped or even shut down if there were no protection. A vital part of the entire endeavor to separate water in the conventional compressed air system is also the trapping of dirt, pipe scale and other contaminates. This is still necessary with a dried air system. As a minimum, all branch lines should be taken off the top of the main and all feeder lines off the top of branch lines. [Pg.643]

All in all, this system is more complicated than the other flow batteries and this handicap postpones wider application. [Pg.206]

It would be erroneous to think that present-day mathematical methods are adequate to explain or predict all that exists in the enormous volume of experimental material that physicists and engineers have accumulated. This is due partially to the fact that we possess fairly uniform theoretical approaches only in the domain of small parameters, and also because conditions in some oases are so complicated that in spite of a knowledge of the theory, one is handicapped by computational difficulties. [Pg.372]

The first and second spectra of plutonium are probably the most thoroughly studied of any in the periodic table insofar as experimental description of the observed spectra and the term analysis is concerned, but a detailed quantum mechanical treatment has been handicapped by their great complexity. Fortunately, the lowest odd and lowest even configurations for both Pu I and Pu II are relatively simple, and parametric studies of the lowest levels of the 5f67s2, 5f56d7s2 and... [Pg.183]

At that time I was handicapped by my remembering a misinterpretation that I had made of some results obtained in 1932 by one of my students, Ralph Hultgren (6). He had begun to make a thorough study of sets of equivalent spd hybrid bond orbitals, and soon found that he could not handle the computational problem in those precomputer days. I pointed out that the best hybrid orbitals have cylindrical symmetry about... [Pg.397]

Congenital myotonic dystrophy is a relatively rare condition in which myotonia (defined electrically) is mostly absent in the affected newborn infant, but becomes apparent in the older infant. Histopathology shows a consistent feature of arrested development and maturation of muscle fibers, but there is, currently, no adequate explanation for this phenomenon. Patients with congenital myotonic dystrophy rarely survive without aggressive ventilatory support, and survivors, without exception, are severely multiply handicapped. [Pg.316]

The numerical model consisted of two alternating procedures During the first one, the creep under applied dead load of a 2-dimensional bar, with an initial small deviation from the straight shape, was simulated the second procedure was the solution to the eigenvalue buckling problem for a bar with a shape developed due to the creep, this approach allowed a prediction of the buckling time with the assumption of the initial imperfection accepted as an unavoidable handicap. [Pg.127]

Most of the microporous and mesoporous compounds require the use of structure-directing molecules under hydro(solvo)thermal conditions [14, 15, 171, 172]. A serious handicap is the application of high-temperature calcination to develop their porosity. It usually results in inferior textural and acidic properties, and even full structural collapse occurs in the case of open frameworks, (proto) zeolites containing small-crystalline domains, and mesostructures. These materials can show very interesting properties if their structure could be fully maintained. A principal question is, is there any alternative to calcination. There is a manifested interest to find alternatives to calcination to show the potential of new structures. [Pg.132]

The main handicap of MD is the knowledge of the function [/( ). There are some systems where reliable approximations to the true (7( r, ) are available. This is, for example, the case of ionic oxides. (7( rJ) is in such a case made of coulombic (pairwise) interactions and short-range terms. A second example is a closed-shell molecular system. In this case the interaction potentials are separated into intraatomic and interatomic parts. A third type of physical system for which suitable approaches to [/( r, ) exist are the transition metals and their alloys. To this class of models belong the glue model and the embedded atom method. Systems where chemical bonds of molecules are broken or created are much more difficult to describe, since the only way to get a proper description of a reaction all the way between reactant and products would be to solve the quantum-mechanical problem at each step of the reaction. [Pg.663]

Today it has become clear that the effect of trace elements in living systems, in food, and in the environment depends on the chemical form in which the element enters the system and the final form in which it is present. The form, or species, clearly governs its biochemical and geochemical behaviour. lUPAC (the International Union for Pure and Applied Chemistry) has recently set guidelines for terms related to chemical speciation of trace elements (Templeton et al. 2000). Speciation, or the analytical activity of measuring the chemical species, is a relatively new scientific field. The procedures usually consist of two consecutive steps (i) the separation of the species, and (2) their measurement An evident handicap in speciation analysis is that the concentration of the individual species is far lower than the total elemental concentration so that an enrichment step is indispensable in many cases. Such a proliferation of steps in analytical procedure not only increases the danger of losses due to incomplete recovery, chemical instability of the species and adsorption to laboratory ware, but may also enhance the risk of contamination from reagents and equipment. [Pg.75]

In the earliest SFG experiments [Tadjeddine, 2000 Guyot-Sionnest et al., 1987 Hunt et al., 1987 Zhu et al., 1987], a first-generation data acquisition method was used, and, because of the limited signal-to-noise ratios, IR attenuation by the electrolyte solution was a substantial handicap. So, in earlier SFG studies, as in IRAS studies, measurements were performed with the electrode pressed directly against the optical window [Baldelli et al., 1999 Dederichs et al., 2000]. With the in-contact geometry, the electrolyte was a thin film of uncertain and variable depth, probably of the order of 1 p.m. However, the thin nonuniform electrolyte layers can strongly distort the potential/coverage relationship and hinder the ability to study fast kinetics. [Pg.378]

Table 1.2 gives a representative sampling of eqnilibrinm constants for additions to varions types of carbonyl compounds. Notice that there are nnmerons gaps in the table. This means that mnch remains to be done in the stndy of carbonyl addition reactions. In trying to devise schemes for predicting the eqnilibrinm constants for snch reactions, the scarcity of experimental data is a serions handicap. There are many fewer equilibrium constants for additions to imines, and even fewer cases where... [Pg.10]


See other pages where Handicapped is mentioned: [Pg.223]    [Pg.178]    [Pg.442]    [Pg.386]    [Pg.250]    [Pg.492]    [Pg.101]    [Pg.495]    [Pg.303]    [Pg.524]    [Pg.570]    [Pg.766]    [Pg.58]    [Pg.512]    [Pg.482]    [Pg.82]    [Pg.376]    [Pg.231]    [Pg.241]    [Pg.390]    [Pg.274]    [Pg.17]    [Pg.179]    [Pg.68]    [Pg.292]    [Pg.120]    [Pg.270]    [Pg.117]    [Pg.328]    [Pg.305]    [Pg.1084]    [Pg.387]   
See also in sourсe #XX -- [ Pg.77 , Pg.176 ]




SEARCH



Community Mental Handicap Teams

Education for All Handicapped Children Act

Handicap

Handicap

Handicap principle

Handicaps Preventing a Broader Commercialization of Fuel Cells

Recycling and valorization the French cultural handicap

The handicapped replicator

© 2024 chempedia.info