Orange estimation

Resonance Raman reflection spectroscopy of monolayers is possible, as illustrated in Fig. IV-14 for cetyl orange [157]. The polarized spectra obtained with an Ar ion laser allowed estimates of orientational changes in the cetyl orange molecules with a. 

Calcium, strontium and barium produce characteristic flame colours like the Group 1 cations (calcium, orange strontium, red barium, green) and flame photometry can be used for their estimation. All give insoluble carbonates in neutral solution. 

Analysis. Dilute aqueous solutions of hydroxyhydroquiaone turn blue-green temporarily when mixed with ferric chloride. The solutions darken upon addition of small amounts, and turn red with additions of larger amounts of sodium carbonate. Derivatives used for identification are the picrate, which forms orange-red needles (mp of 96°C), and the triacetate (mp 96—97°C). Thin-layer chromatography and Hquid chromatography are well suited for the quahtative and quantitative estimation of hydroxyhydroquiaone (93,94). 

Direct Yellow 4, Direct Yellow 11, Direct Yellow 106, and Direct Orange 15 are the most important stilbene dyes, accounting for most sales of this type. Estimated volumes and values for Hquid and powder forms appear in Table 3 (38). 

Flames were first observed at or near an unoccupied caboose. A flash fire resulted, propagating toward the punctured car area. An orange flame then spread upward, and a large vapor cloud flared with explosive force. Estimates of the time lapse between these occurrences range from 2 to 30 seconds. Almost immediately thereafter, a second, more severe, explosion was reported. ... 

One of the most sensitive methods for estimating titanium (or, conversely, for estimating H2O2) is to measure the intensity of the orange colour produced when H2O2 is added to acidic solutions of titanium(IV). The colour is due > to the peroxo complex, [Ti(02)(0H)(H20)jt]", though alkaline solutions are needed before crystalline solids such as M3[Ti(02)Fs] or M2[Ti(02)(S04)2]... 

Quinoxaline-2,3-dithione (2,3-dimercaptoquinoxaline) (90) forms chelates with several transition elements and is used as a colorimetric agent for the detection and quantitative estimation of nickeT and also for the quantitative estimation of palladium. " Nickel gives a pink coloration with (90) in ammoniacal solution, and palladium an orange-red color in AA-dimethylformamide solution containing a little hydrochloric acid. Spectrophotometric studies of the chelate compounds of (90) with Ni(II), Co(II), and Pd(II) in alkaline solu-... 

In all the foregoing cases, the percentage of aldehyde or ketone is so high that the estimation by the above processes can be sufficiently accurately carried out on the original oil. With such oils as lemon, orange, hand-pressed lime, and citron or cedrat, however, the proportion of aldehydes is so small that it is not possible to satisfactorily determine it directly on the oil itself by absorption processes, and a preliminary concentration of the aldehydes in the oils by carefully fractionating out the hydrocarbons in vacuo has therefore been proposed by Burgess and Child who recommend the operation to be carried out as follows —... 

Sodium Chloride [25]. Sodium chloride estimation is based on sodium titration. To 20 ml of a 1 1 mixture of toluene (xylene) isopropyl alcohol, add a 1-ml sample of oil-base mud, stirring constantly and 75 to 100 ml of distilled water. Add 8-10 drops of phenolphthalein indicator solution and titrate the mixture with H SO (N/10) until the red (pink) color, if any, disappears. Add 1 ml of potassium chromate to the mixture and titrate with 0.282N AgNO (silver nitrate, 1 ml = 0.001 g chloride ions) until the water portion color changes from yellow to orange. Then... 

Schiesser and Lapidus (S3), in later studies, measured the liquid residencetime distribution for a column of 4-in. diameter and 4-ft height packed with spherical particles of varying porosity and nominal diameters of in. and in. The liquid medium was water, and as tracers sodium chloride or methyl orange were employed. The specific purposes of this study were to determine radial variations in liquid flow rate and to demonstrate how pore diffusivity and pore structure may be estimated and characterized on the basis of tracer experiments. Significant radial variations in flow rate were observed methods are discussed for separating the hydrodynamic and diffusional contributions to the residence-time curves. 

Very approximately the S2O content of a gas mixture can be estimated from the color of the condensate at -196 °C in a glass trap (provided that all other components are colorless at this temperature). Due to the formation of highly colored decomposition products the condensate is yellow at <2 mol% S2O, orange-yellow at 5-10%, orange at 20-30%, cherry-red at 40-70%, and dark-red at >85% [10]. These colors [14] are caused by small sulfur molecules like S3 and 84 [15, 16] as well as by sulfur radicals formed in the radical-chain polymerization of S2O to polysulfuroxides (S 0)x and SO2 [10, 17] ... 

Figure 9 summarizes the electrode responses toward a variety of DNA-binding substrates [14c]. For intercalators (quinacrine, acridine orange, and safranin) and groove binders (spermine and spermidine), a steep rise followed by a saturation of the concentration response curve is commonly observed. If one compares the specific concentration which gives a 50% response in the increment of the cathodic peak current (A/p ) for each substrate, a selectivity order of quinacrine acridine orange > spermine > spermidine > safranin can be estimated. The binding constants measured in aqueous media for the affinity reaction with ds DNA are as follows quinacrine, 1.5 x 10 (38 mM NaCl)... 

Comparisons between observed data and model predictions must be made on a consistent basis, i.e., apples with apples and oranges with oranges. Since models provide a continuous timeseries, any type of statistic can be produced such as daily maximums, minimums, averages, medians, etc. However, observed data are usually collected on infrequent intervals so only certain statistics can be reliably estimated. Validation of aquatic chemical fate and transport models is often performed by comparing both simulated and observed concentration values and total chemical loadings obtained from multiplying the flow and the concentration values. Whereas the model supplies flow and concentration values in each time step, the calculated observed loads are usually based on values interpolated between actual flow and sample measurements. The frequency of sample collection will affect the validity of the resulting calculated load. Thus, the model user needs to be aware of how observed chemical loads are calculated in order to assess the veracity of the values. 

Method performance study All laboratories follow the same written protocol and use the same test method to measure a quantity (usually concentration of an analyte) in sets of identical test samples. The results are used to estimate the performance characteristics of the method, which are usually within-laboratory- and between-laboratory precision and - if relevant - additional parameters such as sensitivity, limit of detection, recovery, and internal quality control parameters (IUPAC Orange Book [1997, 2000]). 

The identification of anionic polyfacrylic acid) sizes can be carried out by staining with a fluorescent cationic dye (Cl Basic Orange 14) followed by spectroscopic measurement of excitation wavelength and fluorescence emission [195,196]. Such methods can also be used (with Cl Basic Orange 14 or Cl Basic Red 1) to detect and estimate carboxymethylcellulose, poly(vinyl alcohol) and starch derivatives [197]. 

The ease of formation of hydrophobic ion pairs, and hence the rate acceleration, will be determined by the hydrophobic and electrostatic interactions between the anionic and cationic species. Lapinte and Viout (1974) found that the nucleophilic order OH- > CN > C6H50- in water was completely reversed in CTAB micelles hydrophobic phenoxide ion is activated better by the micelle. The micellar binding of phenols and phenoxides was determined by Bunton and Sepulveda (1979). Similarly, hydrophobic hydroxamates are activated much better than their hydrophilic counterparts. In the same vein, the extent of activation correlates approximately with the hydrophobic nature of aqueous aggregates as estimated by Amax of methyl orange (Table 7) and of picrate ion (Bougoin et al., 1975 Shinkai et al., 1978f Table 5). 

Fig. 6 Typical PET probes (a) and representative fluorescence light-up responses toward selected metal ions in tabulated (b) and graphical form (c trace 1 = 14, trace 2 = 14-(Zn2+)2, trace DMA = 9,10-dimethylanthracene in MeCN). Color code coordinating atoms in blue, atoms which take part in the complexation and show (main, in 14) PET activity in orange, fluorophore in green. Lincoln and co-workers have demonstrated that the attachment of two dimethylamino groups through propylene spacers to the 9,10-positions of anthracene has a more than 100-fold weaker PET activity than the attachment through methylene spacers [62]. The blue N atoms in 14 are thus predominantly responsible for coordination. For symbols, see Fig. 3. Quantum yield of 14 in MeCN estimated from intensity readings published in [61] and quantum yield data of the parent compound without active PET, DMA, published in [63]. (Reprinted in part with permission from [61]. Copyright 1988 American Chemical Society)...

Fig. 3.156. The structure and molecular mass of Orange II and estimated degradation products. Reprinted with permission from S. Takeda et al. [196].

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