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A Sampling of Applications

A sampling of applications of Kamlet-Taft LSERs include the following. (/) The Solvatochromic Parameters for Activity Coefficient Estimation (SPACE) method for infinite dilution activity coefficients where improved predictions over UNIFAC for a database of 1879 critically evaluated experimental data points has been claimed (263). (2) Observation of inverse linear relationship between log 1-octanol—water partition coefficient and liquid... [Pg.254]

The development of polymeric drug delivery devices for sustained ophthalmic CsA release is an active area of research for uveitis, vitreous inflammation, dry eye, and prevention of cornea transplant rejection. The use of these specialized CsA-delivering ophthalmic systems (e.g., implants nanoparticle and microsphere injections) cannot be completely reviewed in this chapter and readers are referred to an alternative text. A sample of applicable polymers for delivery of CsA for uveitis and vitreous inflammation is offered in the accompanying table (Table 15.4). The treatment of posterior uveitis and vitreous inflammation usually involves chronic therapy (often years) of topical agents and frequent intravitreal injections for disease control. These therapies are often impractical and subject to medical non-adherence [33]. Polymeric implants or injectable polymer sustained release systems can potentially improve patient outcomes through optimized intraocular drug concentrations. [Pg.429]

In this section, the wide diversity of teclmiques used to explore ion chemistry and ion structure will be outlined and a sampling of the applications of ion chemistry will be given in studies of lamps, lasers, plasma processing, ionospheres and interstellar clouds. [Pg.798]

Figure 2.5 shows some actual experimental data for versus 7, measured on a sample of polyethylene at 126°C. Note that the data are plotted on log-log coordinates. In spite of the different coordinates. Fig. 2.5 is clearly an example of pseudoplastic behavior as defined in Fig. 2.2. In this and the next several sections, we discuss shear-dependent viscosity. In this section the approach is strictly empirical, and its main application is in correcting viscosities measured... Figure 2.5 shows some actual experimental data for versus 7, measured on a sample of polyethylene at 126°C. Note that the data are plotted on log-log coordinates. In spite of the different coordinates. Fig. 2.5 is clearly an example of pseudoplastic behavior as defined in Fig. 2.2. In this and the next several sections, we discuss shear-dependent viscosity. In this section the approach is strictly empirical, and its main application is in correcting viscosities measured...
A certain change in a manufacturing procedure for producing component parts is being considered. Samples are taken by using both the existing and the new procedures in order to determine whether the new procedure results in an improvement. In this application, it is of interest to demonstrate statistically whether the population proportion po for the new procedure is less than the population proportion pi for the old procedure on the basis of a sample of data. [Pg.499]

Sounds with a boiling point above 100° C). Figure 25-42 presents an lustration of the Method 0010 sampling train. Comprehensive chemical analyses, using a variety of applicable analytical methodologies, are conducted to determine the identity and concentration or the organic materials. [Pg.2207]

In this section, a number of applications for NRA are presented. As this is not a review article, the following is only a sampling of the possible uses of this powerful technique. The reader interested in information on additional applications is directed to the proceedings of the Ion Beam Analysis Conferences and those from the International Conferences on the Application of Accelerators in Research and Industry, among other sources. [Pg.690]

Adhesives are not used Just for structural applications on modern aircraft. In fact, the number of non-structural applications of adhesives vastly outnumbers the structural applications. Adhesives are used for everything from assembling lavatory walls to attaching the No Smoking sign to cabin partitions. Just a sampling of adhesive types and applications are discussed below. [Pg.1185]

One of tlte principal applications of the normal distribution in reliability calculations and liazard and risk analysis is tlte distribution of lime to failure due to wearout. Suppose, for example, tliat a production lot of a certain electronic device is especially designed to withstand liigh temperatures and intense vibrations lias just come off the assembly line. A sample of 25 devices from tlie lot is tested under tlie specified heal and vibration conditions. Time to failure, in hours, is recorded for each of the 25 devices. Application of Eqs. (19.10.1) and... [Pg.588]

Discussion. One very important application of potassium dichromate is in a back-titration for the environmental determination16 of the amount of oxygen required to oxidise all the organic material in a sample of impure water, such as sewage effluent. This is known as the chemical oxygen demand (C.O.D.) and is expressed in terms of milligrams of oxygen required per litre of water, mg L l. The analysis of the impure water sample is carried out in parallel with a blank determination on pure, double-distilled water. [Pg.378]

The Karl Fischer procedure was applied to the determination of water present in hydrated salts or adsorbed on the surface of solids. The procedure, where applicable, was more rapid and direct than the commonly used drying process. A sample of the finely powdered solid, containing 5-10 millimoles (90-180 mg) of water, was dissolved or suspended in 25 mL of dry methanol in a 250-mL glass-stoppered graduated flask. The mixture was titrated with standard Karl Fischer reagent to the usual electrometric end point. A blank titration was also carried out on a 25 mL sample of the methanol used to determine what correction (if any) needed to be applied to the titre obtained with the salt. [Pg.638]

Precipitation reactions have many applications. One is to make compounds. The strategy is to choose starting solutions that form a precipitate of the desired insoluble compound when they are mixed. Then we can separate the insoluble compound from the reaction mixture by filtration. Another application is in chemical analysis. In qualitative analysis—the determination of the substances present in a sample—the formation of a precipitate is used to confirm the identity of certain ions. In quantitative analysis, the aim is to determine the amount of each substance or element present. In particular, in gravimetric analysis, the amount of substance present is determined by measurements of mass. In this application, an insoluble compound is precipitated, the precipitate is filtered off and weighed, and from its mass the amount of a substance in one of the original solutions is calculated (Fig. 1.6). Gravimetric analysis can be used in environmental monitoring to find out how much of a heavy metal ion, such as lead or mercury, is in a sample of water. [Pg.93]

While it is true, therefore, that a general method for analysis could be developed and used successfully for a number of applications based on previous knowledge, for those in which optimum performance is required it is advisable to carry out preliminary experiments in which the variables of ionization technique, polarity, cone-voltage, etc., as well as those of sample isolation, are investigated (see Section 5.1 above). [Pg.249]

C22-0050. The iron isotope with 33 neutrons is used in medical applications. It is a P emitter. A sample of iron containing 1.33 picograms (pico = 10 ) of this isotope registers 242 decays per second. [Pg.1615]

Prototypical application examples. To provide a more concrete notion of the type of systems where our approaches are expected to be particularly helpful and useful, we conclude this section with a sample of prototypical examples of what the performance metric, y, in the problem statement (2) may represent, together with a definition of the corresponding systems ... [Pg.104]

The stndies of variation patterns in Lasthenia and Brickellia hardly break the snrface of a vast and complex literatnre on chemical variation within Asteraceae. The snbject has been discnssed in detail, with reviews focnsing on polyacetylenes (Bohlmann et al., 1973), sesqniterpene derivatives (Seaman, 1982), and flavonoids (Bohm and Stnessy, 2001). The next examples come from the sesqniterpene lactone literatnre and, again, represent only a sample of the applications that have been made nsing those data. Examples covering the taxonomic hierarchy within Asteraceae np to the early 1980s can be fonnd in the monumental review of the family prepared by Seaman (1982). [Pg.94]

The use of immunoassays for the determination of pesticides and veterinary medicines in food animals has increased since the early 1990s. The advantages of simple analysis, quick results, and high throughput make immunoassays a powerful technique for problematic matrices commonly encountered in animal agriculture. Careful development and validation are required to obtain accurate results, however. This review has demonstrated that most immunochemical techniques have been designed for use with milk samples, but a number of applications have also been developed for liver and muscle samples. The development of immunoassay techniques for residue analysis in eggs has clearly not been pursued to the extent of other edible tissues. [Pg.709]

The most common and diverse approach to cleanup (and extraction of water samples) in pesticide residue analysis is SPE. Over the last 20 years, improvements and diversifications in SPE formats, sorbent types, and apparatus have made SPE a widely used approach for a variety of applications, including the analysis of pesticide residues. SPE cartridges or disks can be likened to low-resolution HPLC columns in that similar stationary and mobile phases are used. A typical particle size in SPE is 40 pm, and the plastic cartridges are generally packed with 0.1-1 g of sorbent in plastic tubes. The choice of reversed-phase, normal-phase, and ion-exchange media in SPE is very diverse, and Table 2 lists some of the more popular SPE applications for the cleanup of pesticides. [Pg.760]

A sample of hops which had been treated with tetraethyl pyrophosphate showed a negative chemical analysis. The plant material was also extracted and the extract added to the drinking water of test animals and sensitive insects. The animals and insects that drank this treated water for several days showed no reaction. With the sensitive insects it would have been possible to detect even a few parts per million. In addition, there have been extensive commercial field applications of the chemical in dust and spray form to crops such as apples, pears, grapes, celery, broccoli, Brussels sprouts, and others up to within a few days of harvest there has been no detectable poison residue on any of the crops. The lack of poison residue with use of tetraethyl pyrophosphate is due to the fact that it hydrolyzes within a few hours of application, breaking down into transient nonresidual and nonpoisonous chemicals. Thus it is possible to use tetraethyl pyrophosphate well up to harvest time of food products without danger of residual poison on crops. The fact that the chemical is used in extremely small amounts is a definite advantage in respect to freedom from poison residue. [Pg.107]

A sample of alfalfa hay from Bozeman, Mont., that had received two spray applications, each of 4 pounds of technical toxaphene per acre, was found by the method recommended by Carter and Hubanks (3) to contain 225 p.p.m. of organic chlorine, equivalent to 331 p.p.m. of toxaphene. This sample was obtained from a bale approximately 5 months after the last spray application. A similar sample of untreated hay was found to contain 1.2 p.p.m. of organic chlorine. [Pg.271]

This section describes the applicable national regulatory requirements for bleached, unbleached, and dissolving kraft mills. Potential pollutants of concern for kraft pulp mills as reflected in the effluent limitations guidelines and standards promulgated by U.S. EPA and in a sampling of NPDES permits are summarized in Table 21.12. [Pg.888]


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A Sample Application

A samples

Application of samples

Sample application

Sample applicator

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