Chlorophyll characteristics

Green Alga An alga in which the green of chlorophyll characteristically is not obscured by other pigments. 

TABLE 1. Changes induced by the mutation in cowpea in chlorophyll characteristics, leaf absorptivity and the characteristics of DCMU-binding to thylakoids. Standard errors of means are given in parenthesis. 

Abridged Spectrophotometry. It is not always necessary to obtain complete spectrophotometric curves in order to measure physical characteristics related to color. The procedure can often be considerably simplified by some abridged form of spectrophotometry. Measurements may be made only at critical wave lengths or wave-length bands, as has been done to determine chlorophyll degradation (1, 8). In such instances the real problem that faces the investigator is to establish the critical wave lengths. 

Bjorkman, O. Demmig, B. (1987). Photon yield of oxygen evolution and chlorophyll fluorescence characteristics at 77 K among vascular plants of diverse origins. Planta, 170, 489-504. 

This chapter brings together information concerning structural features, spectral characteristics, distributions, and functions of major chlorophylls in photosynthetic organisms. Other topics discussed include biosynthesis and degradation in senescent plants and ripening fruits and potential biological properties of chlorophylls. 

Chlorophylls c have characteristic bands between 578 and 630 nm and between 443 and 450 mn that correspond to the Q-band and the Soret band, respectively. ... 

The aim of this chapter is to provide a concise synopsis of the factors that promote degradation during post-harvest handling, processing, and storage, and the strategies to preserve the green color of the most commonly consumed chlorophyU-rich foods. Some considerations about the production and characteristics of natural and semisynthetic chlorophyll derivatives for use as food colorants are also presented. 

The development and reports of methods for colorless chlorophyll derivative (RCCs, FCCs, and NCCs) analysis are relatively recent and the structures of the compounds are being elucidated by deduction from their chromatographic behaviors, spectral characteristics (UV-Vis absorbance spectra), mass spectrometry, and nuclear magnetic resonance analysis. The main obstacle is that these compounds do not accumulate in appreciable quantities in situ and, moreover, there are no standards for them. The determination of the enzymatic activities of red chlorophyll catabolite reductase (RCCR) and pheophorbide a monoxygenase (PAO) also helps to monitor the appearance of colorless derivatives since they are the key enzymes responsible for the loss of green color. ... 

The automated EXAMS model consists of a set of FORTRAN programs which calculates the fate, exposure and dissipation of the chemical from input environmental data such as 1) Global parameters (rainfall, irradiance, latitude), 2) Biological parameters (biomass, bacterial counts, chlorophyll), 3) Depths and in-lows, 4) Sediment characteristics, 5) Wind, 6) Evaporation, 7) Aeration, 8) Advective and turbulent interconnections, 9) Water flow, 10) Sediment flow, 11) pH and pOH, and 12) Temperature. Also characteristics of the chemical are taken into account such as hydrolysis photolysis, oxidation, biolysis, and volatility. 

Figure 9.5 J-V characteristic of the devices using chlorophyll (full triangles), anthocyanin (open triangles), and their mixture (circles).

A characteristic example of the application of this very modern method is described under chlorophyll (p. 410). 

The action spectrum for the light requirement shows maximal quantum responsivity at 420 and 480 nm and low responsivity at wavelengths characteristic of chlorophyll (PAN at 4 ppm for 15 min). The action... 

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