Growth stage

A kinetic model for the particle growth stage for continuous-addition emulsion polymerization has been proposed (35). Below the monomer... 

This reaction may then repeat itself many times so that several thousand monomer units are joined together in a time of the order of 1 second, leading to a long chain free radical. This is the propagation or growth stage. 

A. M. Kierzek, W. M. Wolf, P. Zielenkiewicz. Simulations of nucleation and early growth stages of protein crystals. Biophys J 75 571, 1997. 

The water solubilities of the functional comonomers are reasonably high since they are usually polar compounds. Therefore, the initiation in the water phase may be too rapid when the initiator or the comonomer concentration is high. In such a case, the particle growth stage cannot be suppressed by the diffusion capture mechanism and the solution or dispersion polymerization of the functional comonomer within water phase may accompany the emulsion copolymerization reaction. This leads to the formation of polymeric products in the form of particle, aggregate, or soluble polymer with different compositions and molecular weights. The yield for the incorporation of functional comonomer into the uniform polymeric particles may be low since some of the functional comonomer may polymerize by an undesired mechanism. 

Low luciferin content. Luminous fungus in various growth stages contains relatively small amounts of luciferin that can sustain the luminescence for a period of only 3-100 s, in resemblance to the situation found in luminous bacteria. In luminous bacteria,... 

Figure 2. Determination of reaction order for Pu(IV) polymer growth stage at 50° C. Sloped 3 for all HNO, concentrations indicated. (Reprinted with permission from Ref. 2.)...

Regulation of life cycle timing so that moisture-sensitive growth stages do not coincide with times when water stress is likely to occur. 

At the initial growth stage, crystals of adamantane show only cubic and octahedral faces. The effects of this unusual stmcture on physical properties are interesting [5]. 

Hegde RS, JS Fletcher (1996) Influence of plant growth stage and season on the release of root phenolics by mulberry as related to development of phytoremediation technology. Chemosphere 32 2471-2479. 

As a rule, short nucleation times are the prerequisite for monodisperse particle formation. A recent mechanistic study showed that when Pt(acac)2 is reduced by alkylalu-minium, virtually all the Pt cluster nuclei appear at the same time and have the same size [86]. The nucleation process quickly consumes enough of the metal atoms formed initially to decrease their concentration below the critical threshold. No new metal cluster nuclei are created in the subsequent diffusion-controlled growth stage. 

The basic principle of chemical synthesis of nanoparticles is to initiate chemical reactions and control the nu-cleation and growth of the reaction products. In order to achieve monodispersity, LaMer has shown that the separation of the nucleation stage from the growth stage is an important factor to be considered (Figure 1). 

Pulse labeling—field Growth stage or plant age Barley (Hordeum vidgare) 49... 

Growth stage or plant age management practice Barley, wheat 54. 55... 

A detailed description of the test system (crop) should be given in the study plan. Information on the growth stage and development of the crop (especially for the period... 

A description of the trial area, which includes a layout of the plots, the previous history of the trial area, a description of the plots, special local features, and the ownership of the land, should be recorded. Increasingly, digital photography is used to document site location, type of application used, crop growth stage, etc. 

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