Field condition effects

FIGURE 7.1 S = 3/2 rhombograms for weak-field and intermediate-field conditions. Effective g-values are plotted for v = 9.50 GHz and D = 3.0 cm"1 (weak field solid lines) or D = 0.3 cm"1 (intermediate field broken lines) as a function of the rhombicity E/D. 

Micozzi, M. S. (1986). Experimental study of postmortem change under field conditions Effects of freezing, thawing and mechanical injury. /. Forensic Sci. 31, 953-961. 

Durability. Grass-like surfaces intended for heavy-duty athletic use should have a service life of at least eight years, a common warranty period provided by suppHers. Lifetime is more or less proportional to the ultraviolet (uv) exposure (sunlight) and to the amount of face ribbon available for wear, but pile density and height also have an effect. Color is a factor generally uv absorption is highest with red fabrics and least with blue. In addition, different materials respond differendy to abrasive wear. These effects caimot be measured except in simulated field use and controlled laboratory experiments, which do not necessarily redect field conditions. 

Deniz, S., Greitzer, E. and Cumpsty, N., 1998, Effects of Inlet Flow Field Conditions on the Performance of Centrifugal Compressor Diffusers Part 2 Straight-Channel Diffuser, ASME Paper No. 98-GT-474. 

What will happen under field conditions is, however, highly uncertain. Laboratory experiments have been conducted under conditions of abundant nutrients and water, ideal temperatures, and no competition among experimental plants. Such conditions are rare in the field. The best prediction is that, whereas increases similar to those found in the laboratory are unlikely under field conditions, increased concentrations of CO2 are likely to ameliorate to some extent the detrimental effects of climate change. However, field-scale experiments under a variety of soils and climates and with several crop plants are needed to provide information on effects of climate change accompanied by higher concentrations of CO2 on agricultural productivity. 

To promote the use of poor quality water for irrigation, a field research study was conducted in three semi-arid regions with water scarceness in Syria in order to define, under field conditions, the wheat yield response function to irrigation water salinity, the effect of soil texture and structural characteristics on the irrigation water salinity threshold, and to compare this value with the conventional threshold value. 

Dowd P.F. Lagrimini L.M. (2006) Examination of the biological effects of high anionic peroxidases production in tobacco plants grown imder field conditions. 1. Insect pest damage. / / Transgenic Research. V. 15. P. 197-204. 

The latter problems are of particular interest to chemists, who should devise appropriate methods for resolving the complexity of chemicals, properly identifying them and finally determining their exact composition and makeup. The participation of chemists is needed to verify the concept of allelopathy as a concentration-dependent phenomenon. They should help to reconstitute the chemical composition as it was found in the original and isolated plant samples. This systematic approach leads to verification of the concept as well as to proper assessment of the initial observation with crude extracts, and to final application to the field situation. Once the concept is proven, same simulation experiments need to be performed to maximize the allelopathic effect (toxin action). The concentration of the toxic chemicals is varied to where the threshold levels of chemicals prove to be involved in the exhibition of allelopathy under field conditions. 

The presence of crop residues has been reported to both increase (5, 6) and decrease crop yields ( 7) and not tilling to increase certain difficult to control weeds (8). However, other reports indicate that the presence of certain mulches can reduce the biomass of certain weeds (9-15) and allow for higher crop yields ( 5, 6). Thus, under certain conditions, mulches can suppress certain weed species, but determining the reason(s) presents many logistical problems, especially under field conditions. To determine the cause(s), the physical and chemical (i.e., allelopathy) effects of the mulch and the role of soil disturbance (or the lack of, as would be the case in a no-till system) must be separated. 

Rapid under field conditions. Rain destroys effectiveness. Heavy vegetation, jungle, and forests cause considerable loss by hydrolysis on leafy surfaces. 

Hofer, I., and Battig, K., Cardiovascular, behavioral, and subjective effects of caffeine under field conditions. Pharmacology, Biochemistry and Behavior 48(4), 899-908, 1994. 

Hofer, I., Battig, K., Psychophysiological effects of switching to caffeine tablets or decaffeinated coffee under field conditions. Special Issue Caffeine research. Pharmacopsychoecologia 7(2), 169-177, 1994. 

Unfortunately, it has not been possible to develop an ideal economic poison which has a low order of toxicity for man and is effective over a wide variety of field conditions. Cooperative research on the part of chemists and toxicologists should be directed toward the development of economic poisons possessing a greater margin of safety for man and animals. 

Aldrin, like chlordan, exhibits residual effectiveness under field conditions for somewhat less than 3 weeks. Even when aldrin is applied at the uneconomical and unnecessary rate of 5 pounds per acre, leafy material so treated exhibits only slight insect toxicity after 3 weeks. Aldrin, therefore, falls into that class of materials which exhibit pronounced initial toxicity but relatively short residual action. 

U.S. EPA s Method 909040 can be used to evaluate all geosynthetic materials used in liner and LCRSs currently being designed. Method 9090 is used to predict the effects of leachate under field conditions and has been verified with limited field data. The test is performed by immersing a geosynthetic in a chemical environment for 120 days at two different temperatures room and elevated temperature. Every 30 days, samples are removed and evaluated for changes in physical properties. Tests performed on FMLs are listed in Table 26.7. The results of any test should be cross-referenced to a second, corollary test to avoid errors due to the test itself or to the laboratory personnel. 

Chemical parameters (e.g., partition coefficients, decay rates, temperature and moisture effects) are not usually considered as calibration parameters because they can be measured in a laboratory moreover, calibration is usually not possible due to lack of observed data. However, most scientists will agree that extrapolation of laboratory parameter measurements to field conditions is a risky assumption. If observed chemical data are available, refinement of initial chemical parameters through calibration should be considered. Errors in calibration-derived parameter values are often a function of how much calibration was performed or errors in system inputs and/or outputs. In many modeling efforts, conscientious model users will often overrun the calibration budget because of the natural tendency to continue to make calibration runs in an effort to minimize discrepancies between simulated and observed values. Parameter errors associated with calibration are more often a result of missing and/or erroneous data either as system inputs or outputs. 

Zaman M, Nguyen ML. Effect of lime or zeolite on NzO and N emissions from a pastoral soil treated with urine or nitrate-N fertiliser under field conditions. Agriculture Ecosystems and Environment. 2010 136 254—261. 

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