Water relationship

Equation 12-18 gives a eonservative estimate of the vent area, and the simple design method represents overpressure (AP) between 10%-30%. Eor a 20% absolute overpressure, a liquid heat eapaeity of 2,510 J/kg K for most organies, and eonsidering that a saturated water relationship exists, the vent size area per 1,000 kg of reaetants is ... 

However, few studies have been conducted because of analytical difficulties during extraction and measurement such as re-adsorption or incomplete removal, and the low temporal resolution that can be achieved Also, it is considered likely that the global meteoric water relationship in Equation (6) does not apply consistently across the globe... 

EINHELLIG ET al. Effects of Allelochemicals on Plant- Water Relationships 181... 

EINHELLIG et AL. Effects of AUelochemicals on Plant- Water Relationships 183... 

Equation 9-24 provides a conservative estimate of the required vent area. By considering the case of 20% absolute overpressure, assuming a typical liquid heat capacity of 2510 J/kg K for most organic materials, and assuming a saturated water relationship, we can obtain the following equation13 ... 

Schmidt, S.J. 1991. Determination of moisture content by pulsed nuclear magnetic resonance spectroscopy. In Water Relationships in Foods (H. Levine and L. Slade, eds), pp. 599-613. Plenum Press, New York. 

In places where there are concerns about buried materials or sources of contamination, ground penetrating radar (GPR) surveys may be helpful in determining the best sampling approach. GPR can also detect coarse textured subsoils and water relationships in soils having these types of horizons. However, there are some limits as to where GPR can be used and the equipment for doing a GPR survey is expensive [3],... 

Van Maanen JM, Welle IJ, Hageman G, Dallinga JW, Mertens PL, Kleinjans JC (1996) Nitrate contamination of drinking water Relationship with HPRT variant frequency in lymphocyte DNA and urinary excretion of N-nitrosamines. Environ Health Perspec 104 522-528... 

Figure 4. A. Water relationships and diffusion paths for starch-plastic film in a moist environment. Lightly shaded area indicates thin water layer on surface arrows show diffusion paths for enzymes produced by microbes on film surface. B. Same as 4 A., except that film is inunersed in water.

Phenolic acids interfere with many major physiological processes of higher plants (35). These disruptions of function include an alteration of plant water balance. We found depression of leaf water potential to be an early indicator of allelochemical stress from ferulic and p-coumaric acids (42). Likewise one mechanism of allelopathic action by cultivated sunflower, velvetleaf Abutilon theophrasti Medic.), Koahia [Koahia saoparia (L.) Schrad.], and several other weeds was water stress (43-45). Since some allelochemicals interfere with plant-water relationships, it seemed logical that their action might be most critical at times when plants are under water stress from other causes. 

Although indirect and probably quite rare, another route has been reported for allelochemical interference with plant-water relationships. Lovett and Duffield (47) identified benzylamine as an allelochemical in the leaf washings from the cruciferous weed Cametina sativa (L.) Crantz. Subsequent work showed benzylamine induced hydrophobic conditions in the soil, and these conditions could reduce water availability for plant growth (48). Thus, indirect action through changes in soil structure could be partially responsible for adverse effects on linseed (Linseed usitatissimm L.) and could enhance more direct allelopathic effects. 

It is my belief that many of the reactions characteristic of living processes have more to do with the water relationships of the organism than with any other single factor. ... 

Barkosky RR, Einhellig FA, Butler JL. 2000. Caffeic acid induced changes in plant-water relationships and photosynthesis in leafy spurge (Euphorbia esula). J Chem Ecol 26 2095-2109. 

Wolfe S, Kim CK, Yang K. Ab initio molecular orbital calculations on the neutral hydrolysis and methanolysis of azetidinones, including catalysis by water. Relationship to the mechanism of action of P-lactam antibiotics. Can J Chem 1994 72 1033-1034. 

Nordberg GF. 1990. Human health effects of metals in drinking water Relationship to cultural acidification. Environ Toxicol Chem 9 887-894. 

Fritschen, L. J. in "Atmospheric and soil-plant-water relationships." Tech. Rept. ECON 2-66P-A. U.S. Army Electronic Command, Ft. Huachuca, Ariz. 1966. 

Various examples exist of the use of msPAF in multiple-stress analysis to acknowledge the relative role of toxicant mixtures in shaping ecological communities. Mulder et al. (2004) studied the decline of butterfly populations in a nature reserve in The Netherlands. It appeared difficult to establish associations between decline and the major environmental parameters, such as pH and water relationships. 

Copper is an essential element. Copper plays a significant role in several physiological processes - photosynthesis, respiration, carbohydrate distribution, nitrogen reduction and fixation, protein metabolism, and cell wall metabolism. Many plant metalloenzymes contain copper. It also influences water permeability of xylem vessels and thus controls water relationships. It is mainly complexed with organic compounds of low molecular weight and with proteins (Henze and Umland, 1987). Kabata-Pendias and Pendias (1984) have compiled data on the Cu concentrations in... 

Tomka I. In Levine H, Slade L, eds. Water Relationships in Food. New York, NY Plenum Press 1991 627-637. 

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