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The Second Requirement

To meet the second requirement of a cubic spline, the first differential must equal the first differentialyyvt/ t the tenor point x j. [Pg.101]

We know from our conditional working environment that at nodex y+j for functiony/v that = (x r -x y). We also know from the same assumption that X = 0 at the start of the next polynomial, i.e. for functiony y+iTherefore  [Pg.101]


Selection of a name for a specific compound is heavily influenced by the purpose at hand communication to a general audience, communication with specialists, or storage/retrieval through archival indexes. The first requires the simplest rules possible the second requires the shortest names possible and the third requires rigid adherence to a set of rules that will reliably generate a unique name. The name chosen may be different for each situation, although that is not necessarily so. [Pg.35]

The requirements derived in Eq. (10-5) are relevant in the cathodic protection of distribution networks for low and as uniform as possible values of resistance and leakage loading. The second requirement is often not fulfilled with old pipeline networks on account of their different ages and the type of pipe coating. When setting up cathodic protection, a distinction must be made between old and new steel distribution networks. [Pg.283]

The standard free energy can be divided up in two ways to explain the mechanism of retention. First, the portions of free energy can be allotted to specific types of molecular interaction that can occur between the solute molecules and the two phases. This approach will be considered later after the subject of molecular interactions has been discussed. The second requires that the molecule is divided into different parts and each part allotted a portion of the standard free energy. With this approach, the contributions made by different parts of the solvent molecule to retention can often be explained. This concept was suggested by Martin [4] many years ago, and can be used to relate molecular structure to solute retention. Initially, it is necessary to choose a molecular group that would be fairly ubiquitous and that could be used as the first building block to develop the correlation. The methylene group (CH2) is the... [Pg.54]

Oxygen, the second requirement for combustion, is generally not limiting. Oxygen in the air is sufficient to support combustion of most materials within certain limits. These limitations are compound specific and are called the explosive limits in air. The upper and lower explosive limits (UEL and LEL) of several common materials... [Pg.172]

Initial activity is important to ensure fast unloading and loading cycles. The second requirement for repeated use of alanate batteries is long-term stability. Whereas titanium colloids show superior performance in terms of decomposition kinetics, titanium nitride-based materials are superior in long-term stability. The latter can be seen comparing both catalytic materials in several runs (Fig. 19.8). [Pg.287]

The second requirement referring to the mobile phase is the volatility of its components isolated from scraped adsorbent or eluted by online chromatography. [Pg.283]

The second requirement is that enforcement methods for food must be validated by an independent laboratory [independent laboratory validation (ILV)]. The sample set is identical with the general sample set (see Section 4.1). If the method is identical for all four crop groups (mentioned at the beginning of the section), it may be sufficient to perform the ILV for plant materials with a minimum of two matrices, one of them with a high water content. In the case of food of animal origin, the ILV should be performed with at least two of the matrices milk, egg, meat, and, if appropriate, fat. [Pg.30]

The second requirement is related to chemical imaging applications. Very flat samples are required to avoid problems of depth of field. Even if this is common to every imaging technique, it is in this case coupled with surface pollution problems. Sample preparation must then lead to flat surfaces without surface pollution. For cultural heritage samples,... [Pg.436]

The second requirement of the RMP is a prevention program. The prevention program has 11 elements, compared to the 14 elements of the PSM standard. As shown in Table 3-4, many of these elements are duplicated. Fortunately, the EPA made a deliberate attempt to retain the same requirements wherever possible, although differences exist because the EPA and OSHA have different responsibilities. The first column in Table 3-4 lists each element of the PSM program, and the second column shows the corresponding element of the prevention program (some elements have no equivalence). [Pg.73]

An interesting application of these principles is the prediction of CO dissociation routes on the closed-packed (111) surface of rhodium (see Fig. A.17). Two factors determine how the dissociation of a single CO molecule proceeds. First, the geometry of the final situation must be energetically more favorable than that of the initial one. This condition excludes final configurations with the C and the O atom on adjacent Rh atoms, because this would lead to serious repulsion between the C and O atoms. A favorable situation is the one sketched in Fig. A.17, where initially CO occupies a threefold hollow site, and after dissociation C and O are in opposite threefold sites. The second requirement for rupture of the CO molecule is that the C-0 bond is effectively weakened by the interaction with the metal. This is achieved when the C-O bond stretches across the central Rh atom. In this case there is optimum overlap between the d-electrons of Rh in orbitals, which extend vertically above the surface, and the empty antibonding orbitals of the CO molecule. Hence, the dissociation of CO requires a so-called catalytic ensemble of at least 5 Rh atoms [8,21,22]. [Pg.316]

Typically, microsomal fractions are used for TDI analysis, but in many cases TDI is performed in rCYPs. The ability to use rCYPs for TDI relies on the accurate ability to extrapolate the rCYP data [186]. The second requirement for successful extrapolation of rCYP data is that the clearance pathways of the inhibitor in question are understood. For example, raloxifene has been shown to be a strong MBI of CYP3A4 in microsomes and rCYPs, but in hepatocytes the most predominant pathway is glucuronadation, which would effectively mask any CYP3A4 inactivation observed in... [Pg.223]

Threats to chemical facilities from radioactive contamination could involve two major scenarios. First, the facility or its assets could be contaminated, preventing workers from accessing and operating the facility/assets. Second, the feed water supply could be contaminated. These two scenarios require different threat reduction strategies. The first scenario requires that facilities monitor for radioactive substances as they are brought on-site the second requires that feed water assets be monitored for radioactive contamination. While the effects of radioactive contamination are basically the same under both threat types, each of these threats requires different types of radiation monitoring and different types of equipment. [Pg.203]

The first derivative in Eq. (15.34) is straightforward, while the second requires only standard one-particle perturbation theory,... [Pg.281]

However, a separation of the enantiomers will only be achieved if (i) the complexes have different equilibrium constants so that the two enantiomers have a different average mobility, (ii) the free and the complexed enantiomers have different mobilities and (hi) the exchange between the free and the complexed enantiomers is rapid. As a direct consequence of the second requirement, neutral enantiomers are not resolvable with neutral chiral selectors. [Pg.457]

Nucleophilic substitutions with [ F]fluoride have been largely developed both in aromatic (SNAr) and aliphatic (generally SN2) series. Nucleophilic additions remain rare. F-Nucleophilic radiofluorinations usually do not require any carrier and thus enable the synthesis of products with high specific radioactivity. The SN can be performed either directly on a suitable and generally complex precursor of the target molecule or indirectly via a small labelled precursor. Both approaches present drawbacks the first one generally leads to poor yields and the second requires multistep synthesis and more sophisticated automation processes. [Pg.218]

Considering the second requirement, that is, good dynamic mechanical properties ePTFE-based arterial prostheses must satisfy to improve their functional patency, there are not so many ways to reach this goal. Unfortunately, and due to the intrinsic mechanical characteristics of PTFE, the mechanical behaviour of these prostheses cannot be easily modified. However, different ways have been explored on the one hand, an optimisation of the design of the prostheses... [Pg.393]

The second requirement is that components unique to specific aerosol sources affecting the ambient sample are measured, The precise chemical species will depend on the sources in the airshed under consideration. Most studies will require measurement of certain "basic" particulate matter species including ions, elements, and organic and inorganic carbon,... [Pg.99]

In our opinion the signal-to-noise ratio of Taguchi is not a suitable optimization variable. This has two reasons. The first is that R,=0 cannot be handled by this response. The second reason is that situations can result with the same S/N values, while in a chromatographic context these situations are different. As an example, suppose that there are three mixture compositions which result in a signal to noise ration which is doubtful (i.e. S/N < 0.6, Figure 6.3). The first (continuous line) has almost adequate resolutions at all temperatures. The second (dashed line) has reasonable resolutions at 20 °C, but no resolution at 30 °C. The third (dotted line) has reasonable resolutions at 30 °C, but no resolution at 20 °C. In the laboratory 20 °C occurs often, therefore the last mobile phase composition is unacceptable. A choice between the first and the second requires judgement from the researcher. [Pg.252]

For the synthesis of the second required building block, the chiral allylic bromide 31, we again used our SAMP/RAMP hydrazone methodology for the construction of the stereogenic center. The a-alkylation of the SAMP hydrazones of O-protected 4-hydroxybutanal 40a,b with iodomethane led to the desired products 41 with very good yields and very high stereoselectivities and with the required... [Pg.46]

AI2O3 is six coordinate, the O ions will be four coordinate but if Ar is four coordinate, the ions will be only 2.67 coordinate on average. The principle of maximum symmetry favours the first choice as the second requires at least two different types of ion. [Pg.135]

Herein a is the rate of change of the lower dressed state energy i(t) (black dashed line in Figure 6.10c) evaluated at the inflection points at t = +15 fs, and the Rabi frequency H22 is evaluated at the crossing times. For symmetry reasons, the Landau-Zener probability is the same for both avoided crossings. Now the second requirement concerning the field amplitude is to tailor the Rabi frequency of the main pulse such that = 0.5. Then 50% of the population is transferred... [Pg.260]


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The Second

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