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Pure-line method

Shull, G. H., A pure-line method in com breeding. American Breeders Association Reports 1909, 5, 51-59. [Pg.1527]

Although selection for desired plant types has been going on for centuries and led to new and better cultivars, it was not until the early twentieth century that scientists developed theories and methods that were routinely applied to genetic improvement of soybeans. The first technique or method employed by breeders/geneticists was the pure line method of breeding. In this method no artificial hybridization occurs but... [Pg.59]

Because of the occurrence of ill-conditioning, pure penalty methods have been replaced by more efficient algorithms. In SLP and SQP, a merit function is used within the line search phase of these algorithms. [Pg.288]

The selection of the best analytical line has not been discussed explicitly and deserves attention. Because LEI is at least a two-step process involving laser excitation and thermal ionization steps, many transitions may be preferred for LEI which are not usable by purely optical methods. In other words, excited states which have low fractional populations may produce good LEI sensitivity due to proximity of the laser-populated state to the ionization potential. This makes the choice of the most sensitive LEI lines more complicated but it introduces an important practical advantage for dye laser spectrometry. [Pg.17]

This technique can be applied at a range of gate biases and plotted as a function of channel charge density, gate voltage, or applied lateral electric field. Non-linear models have been proposed for the contact resistance as a function of the applied bias (see, for example, [ffS]), which generally assume a Schottky or other diode-like charge injection from the contact into the channel. The transfer line method can also be used to extract a purely empirical model. [Pg.88]

In addition to the purely electrochemical methods, some on-line as well as off-line combined techniques were used (electrochemistry -I- UV/vis, IR, NMR, EPR, MS, HPLC), for detection and identification of intermediates and products. [Pg.655]

Under these conditions, a study of the antioxidant potential of pure compounds could be carried out. Table 1 shows the values of antioxidant activity (expressed as TEAC) of different compounds of interest, determined by the on-line method (HPLC-ABTS method) and compared with the values obtained by our conventional photometric end-point method. As can be observed, the two most important standard antioxidants, trolox and ascorbic acid, presented similar TEAC using either method. Thus, either can be used as reference to express antioxidant activity, except that trolox has the advantage because it can be used in both hydrophilic and lipophilic assays. The TEAC values of phenolic compounds were underestimated by approximately half when the HPLC-ABTS method was used as compared to the end-point method. This was due to the different reactivities of antioxidants with ABTS", and because, unfortunately, the time dependence of online scavenging activity determinations made it very difficult to obtain the total reaction for the slowest antioxidants, resulting in a partial estimation of this activity. Nevertheless, the HPLC-ABTS method provided important additional information in the form of correlation between the different peaks of a sample and their antioxidant activities. [Pg.99]

The refractive index of a liquid is recorded as where t is the temperature at which the measurement is made, and D refers to the wave length of the D line of sodium. As already pointed out, it is usual to determine both the refractive index and the density of the liquid at 20° in any case they should be determined at the same temperatme. These two constants are useful in assisting the characterisation of a pure hquid they are particularly valuable for ahphatic hydrocarbons and similar compounds where the methods of characterisation by the formation of solid derivatives are not entirely satisfactory. [Pg.1034]

Ma.nufa.cture. The preparation of sulfuryl chloride is carried out by feeding dry sulfur dioxide and chlorine into a water-cooled glass-lined steel vessel containing a catalyst, eg, activated charcoal. Alternatively, chlorine is passed into Hquefted sulfur dioxide at ca 0°C in the presence of a dissolved catalyst, eg, camphor, a terpene hydrocarbon, an ether, or an ester. The sulfuryl chloride is purified by distillation the commercial product is typically 99 wt % pure, as measured by ASTM distillation method D850. [Pg.143]

The constants Cj and C9 are both obtained from Fig. 2-40 Ci, usually from the saturated liquid line and C2, at the higher pressure. Errors should be less than 1 percent for pure hydrocarbons except at reduced temperatures above 0.95 where errors of up to 10 percent may occur. The method can be used for defined mixtures substituting pseiidocritical properties for critical properties. For mixtures, the Technical Data Book—Fehvleum Refining gives a more complex and accurate mixing rule than merely using the pseiidocritical properties. The saturated low pressure value should be obtained from experiment or from prediction procedures discussed in this section for both pure and mixed liquids. [Pg.404]

In principle, therefore, the surface concentration of an element can be calculated from the intensity of a particular photoelectron emission, according to Eq. (2.6). In practice, the method of relative sensitivity factors is in common use. If spectra were recorded from reference samples of pure elements A and B on the same spectrometer and the corresponding line intensities are and respectively, Eq. (2.6) can be written as... [Pg.18]


See other pages where Pure-line method is mentioned: [Pg.59]    [Pg.168]    [Pg.59]    [Pg.168]    [Pg.715]    [Pg.31]    [Pg.57]    [Pg.295]    [Pg.160]    [Pg.49]    [Pg.13]    [Pg.75]    [Pg.55]    [Pg.58]    [Pg.193]    [Pg.40]    [Pg.325]    [Pg.340]    [Pg.249]    [Pg.302]    [Pg.273]    [Pg.481]    [Pg.416]    [Pg.169]    [Pg.170]    [Pg.68]    [Pg.1699]    [Pg.241]    [Pg.200]    [Pg.404]    [Pg.448]    [Pg.37]    [Pg.429]    [Pg.188]    [Pg.195]    [Pg.1315]    [Pg.56]    [Pg.605]    [Pg.465]    [Pg.603]   
See also in sourсe #XX -- [ Pg.168 ]




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Line methods

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