Molecular ratio

The monomers used are second generation petrochemical products. The polymethacrylates are in fact copolymers based on methyl methacrylate and up to C20 molecular weight alcohol methacrylate. The properties of the additive are controlled based on the molecular ratio of these different monomers and their molecular weight. 

Crystallinity in ECH and ECH—EO finished products increases over time, and may be detected by x-ray analysis or differential scanning calorimetry. In synthesizing ECH—EO, the process is designed to maximize random monomer sequence and minimize crystallinity. The ECH—EO molecular ratio in these products ranges from approximately 3 1 to 1 1. 

One of the best oxidation-reduction indicators is the 1,10-phenanthroline-iron(II) complex. The base 1,10-phenanthroline combines readily in solution with iron(II) salts in the molecular ratio 3 base l iron(II) ion forming the intensely red l,10-phenanthroline-iron(II) complex ion with strong oxidising agents the iron(III) complex ion is formed, which has a pale blue colour. The colour change is a very striking one ... 

However, exclusive primary or secondary alkyl phosphates are seldom produced. That is due not only to the expenses of production but to the fact that in practical application the mixture of both esters combined with the rest of unreacted starting material often offers most interesting properties. Changing the molecular ratio of alcohol to P4O10 from 2 1 to 4 1 results in an increase of the secondary ester in the mixture from 35% to 65%. 

Reactions leading to surface-active diamides form emulsions of the hydrated [A1(H20)6]C13 complex. However, by hydrolysis of the RPOCl2-AlCl3 complex with water at a molecular ratio of 1 6-7.5 in methylene chloride at a temperature of -10°C, the A1C13 from the complex reacts selectively forming a precipitation of [A1(H20)6]C13, which can be easily filtered off. From the solvent the alkanephosphonic acid dichloride can be isolated in good quality (Table 4). 

A widely used glass is phosphosilicate (PSG), which is used extensively in semiconductor devices as a passivation and planarization coating for silicon wafers. It is deposited by CVD by the reaction of tetraethyl orthosilicate (TEOS) (C2H50)4Si, and trimethylphosphate PO(OCH3)3, in a molecular ratio corresponding to a concentration of 5 to 7% P. Deposition temperature is usually 700°C and pressure is 1 atm. 

C02-0081. Air Is mostly diatomic molecules of nitrogen and oxygen, in a molecular ratio of 4 1. Draw a molecular picture of a sample of air containing a total of 10 molecules. 

In 1989, we developed colloidal dispersions of Pt-core/ Pd-shell bimetallic nanoparticles by simultaneous reduction of Pd and Pt ions in the presence of poly(A-vinyl-2-pyrrolidone) (PVP) [15]. These bimetallic nanoparticles display much higher catalytic activity than the corresponding monometallic nanoparticles, especially at particular molecular ratios of both elements. In the series of the Pt/Pd bimetallic nanoparticles, the particle size was almost constant despite composition and all the bimetallic nanoparticles had a core/shell structure. In other words, all the Pd atoms were located on the surface of the nanoparticles. The high catalytic activity is achieved at the position of 80% Pd and 20% Pt. At this position, the Pd/Pt bimetallic nanoparticles have a complete core/shell structure. Thus, one atomic layer of the bimetallic nanoparticles is composed of only Pd atoms and the core is completely composed of Pt atoms. In this particular particle, all Pd atoms, located on the surface, can provide catalytic sites which are directly affected by Pt core in an electronic way. The catalytic activity can be normalized by the amount of substance, i.e., to the amount of metals (Pd + Pt). If it is normalized by the number of surface Pd atoms, then the catalytic activity is constant around 50-90% of Pd, as shown in Figure 13. 

Samples are hydrolyzed with hydrochloric acid and stannous chloride solution at elevated temperature, and the evolved carbon disulfide is drawn with an air steam through two gas washing tubes in series containing lead acetate and sodium hydroxide solutions and an absorption tube containing an ethanolic solution of cupric acetate and diethanolamine. Lead acetate and sodium hydroxide remove hydrogen sulfide and other impurities. In the absorption tube, the carbon disulfide forms two cupric complexes of Af,Af-bis(2-hydroxyethyl)dithiocarbamic acid with molecular ratios Cu CS2 of 1 1 and 1 2. These complexes are measured simultaneously by spectrophotometry at 453 nm. 

Fig. 22. Dependence of the absorption spectrum of P/3DMP-C104 (poly-/i-dimethyl pyrrole) on the reducing potentials. The voltages written in the figure are the applied voltages between the working and counter electrodes. The numbers in parentheses are the molecular ratios of the perchlorate ion to a pyrrole ring. Each spectrum is obtained using a different free standing film which has almost the same thickness as the others. Reproduced from [377].

Per-iodic acid oxidation78-80 has been used by many investigators in structural studies because this reagent oxidizes selectively the hydroxyls on adjacent carbon atoms. In the course of their studies, McDonald and Jackson81 found that difructose anhydrides I, II and III and diheterolevulosan reduce per-iodic acid to iodic acid in the following respective molecular ratios 2, 1, 1, and 4 moles of acid per mole of anhydride. 

In Table 4 some examples of these compounds are given from the review of Bodansky (B14). With respect to their effectiveness these compounds depend on the mode of ingestion, absorption and, through the latter, on their concentration in blood. Thus, most of the investigators expressed the MHb-forming capacity of any compound as the average molecular ratio of MHb formed to its dosage (B14). But, the variability... 

Only results obtained with albumin-solubilized bilirubin are given human serum (HS), rat serum (RS), albumin (A), human serum albumin (HA), bovine serum albumin (BA). Figures between parentheses indicate the molecular ratio, bilirubin albumin. 

Most frequently, binding protein is added to the incubation mixtures as either serum or purified serum albumin. With human serum albumin, at equilibrium, the acceptor substrate will largely be protein-bound, when the bilirubin albumin molecular ratio is smaller than one (the dissociation constant of the first binding site of purified human serum albumin is approximately 7 X 10 M with 2 X 10 M for two additional binding sites) (J2). The first binding site of albumin, measured with rat serum, has a dissociation constant of about 5 X 10" M (M8). The unbound fraction will normally not exceed the very low solubility of the pigment. Addition of albumin to an alkaline solution of bilirubin, or its addition immediately after neutralization, prevents colloid formation, if the bilirubin albumin molecular ratio is smaller than one (B25). However, colloidal bilirubin, once formed, cannot be redissolved by the addition of albumin (B26). 

At a bilirubin albumin molecular ratio below one the added binding protein will thus act as a kind of buffer, keeping the concentration of unbound substrate sufficiently low to inhibit colloid formation (B25) or precipitation onto bound bilirubin (B26), and will prevent aspecific binding to cell particulates. The binding protein can also be thought of as a reservoir providing a continuous stream of molecularly dispersed sub-... 

For XV) complexes have been obtained with molecular ratios 1 1 for potassium and sodium salts, 2 3 for rubidium and ammonium thiocyanate, and 1 2 for caesium thiocyanate. The rubidium and ammonium thiocyanate compounds are isomorphous, and the structure of the former was the first of this type to be determined 92). In the crystal there is a 1 1 complex and a molecule of crystallisation of un-complexed (XT). The metal is coordinated by six coplanar oxygen atoms... 

Addition compounds are represented by the formulae of the individual constituent species, with suitable multipliers that define the appropriate molecular ratios of the constituent species, and separated by centre dots. In general, the first symbols determine the order of citation. 

DO- or ACC-perturbations in one of two rr-systems can change the molecular ratio in the co-oligomerization of these tr-systems. 

Bachmann found that the volumes of various liquid imbibed by a silica gel within the region AB was approximately constant although the molecular ratio of imbibed liquid to silica might vary over a very considerable range. 

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