Retting process

With increasing concentration of DHB, the photoproduct forms more slowly, as evidenced by decreasing loss of fluorescence intensity (Table I, entries 1-3). Nevertheless, the concentration of photoproduct(s) and RET from the polymer to photoproduct(s) are expected to increase with time, and stabilization of the polymer will eventually depend upon the capability of the photoproduct(s) to dissipate excitation energy imparted in the RET process. The observed decrease in stabilization efficiency by DHB (based on film discoloration) with exposure time in an accelerometer indicates that DHB is more effective than the photoproduct(s) in dissipating the light energy. Similar spectroscopic studies on polystyrene have led to the same conclusion in this case, as well.6... 

The variables in the retting process itself are the nature of the retting bacteria, the temperature of the water, the rate of water circulation, the water quality (whether hard or Boft), and the duration of the... 

Watzl, Alfred., Ultrasonic flax retting process. International Textile Bulletin, Vol. 49 Issue 5, p. 42, 5p (Oct 2003). 

Isora fibre was separated from the bark of H. isora plant by retting process. Fibre presented in the inner part of the bark was peeled off, washed, and dried. The photographs of the stem, small plant, and the raw fibre are given in Fig. 11.1. Fibre surface was modified using alkali and silane treatments. For alkali treatment, fibres were dipped in 5% NaOH for about 4 h, then washed with water containing httle acetic acid, washed well with water, and dried in an air oven. For silane treatment (Silane A172), the alkali treated fibres were dipped in 1 % silane solution in alcohol water mixture (60 40) for 2 h. The pH of the solution was maintained between 3.5 and 4. The fibres were washed with water and dried. 

Cueto CU, Quintos AG, Peralta CN, Pabnario MS (1978) Pineapple fibres the retting process II. NSDB Technol J 73-79... 

Palmario MS, Cueto CU, Imperial ZS, Tayco SA, SoriagaRP, BuenaventureRV, De Guzman MC (1976) Pineapple fibres the retting process. Sci Rev 17(4) 8-16 Paul NG (1980) Some methods for the utilisation of waste from fibre crops and fibre waste from other crops. Agric Waste 2 313-318... 

Coir fibers are obtained from the husk of the coconut. Coir fiber is generally extracted by mechanical means from the plant [52]. Manilal et al. [52] extracted coir fibers by a closed retting process in an aerobic retting reactor. Bakri and Eichhorn [53] mechanically extracted coir and celery fibers and studied their tensile behaviors in terms of micromechanics. Mothe and Miranda [45] studied the thermal stability and chemical constituent analyses of coir fibers. Khan and Alam [54] investigated the effects of several chemical treatments on the thermal and meachanical properties of coir fibers. Mahato et al. [55] studied the effect of alkalization on the thermal degradation of coir fibers. 

Although in many homogeneous systems fluorophores have distinct and discrete decay constants for their fluorescence, in heterogeneous systems the luminescent molecules have different environments and consequently different energy levels and also pathways for the energy dissipation. Moreover, in the RET processes the distance between the donor and acceptor is not constant but may vary slightly. Then it can be expected that the lifetimes are not sharply defined but they are actually continuously distributed. Mathematically this means that instead of the sum in (40), we have to use a Riemann-Stieltjes integral ... 

---