Growth habit

Shape Control Based on the Crystal Growth Habit... 

Allelopathy found hopeful utilization in plant protection against parasite weeds. The main world parasitic species are the witchweeds (Striga spp.), broomrapes (Orobanche spp.), and eventually dodder (Cuscuta spp.). Witchweeds and broom-rapes attack many economically important crops especially throughout the semi-arid regions. Early detection of parasitic weed infestation and protection is difficult because of the growth habit of a root parasite and huge production of dust-like seeds viable up to 20 years (Kebreab and Murdoch 1999). 

For pollen-allelopathic breeding, plants with tall growth habit and relatively large quantity of pollen should be selected (Murphy and Aarssen 1989). Pollen of these species could be artificially dusted on the stigmatic surface of other plants. This phenomenon is yet to be studied and field tested. 

Shrubs and trees have woody stems or trunks and moderate to tall growth habit and, along with tall growing woody grasses, such as coconut, are long-lived and typically only add leaves to the soil each year. Evergreens and... 

Grasses and other similar plants, which may be annual, biennial, or perennial in their growth habit, do not have woody components, but also add leaves and stems to the soil each year. These leaves and stems decompose over a 1-year period, adding organic matter to the soil surface. Often these leaves seem to decompose faster than tree leaves however, in all cases, the rate of decomposition will largely depend on both the characteristics of the plant material and local environmental conditions. 

Rather ungainly in its growth habit, but very hardy indeed, with weleome winter blossoms on its bare branehes. 

When using willow, strip the bark from the lower part of the rod (or whole stem if you like). This is easily done when newly cut. If the bark is not stripped, the stems will root into the ground. This is a growth habit that can be put to good use, however, in creating "living" willow structures. 

Furthermore, by observing a plant s natural growth habit, it is possible to mimic its normal growing pattern. Certain plants, such as verbascums (or mulleins), scatter themselves... 

Prune plants to create an open growth habit to allow good airflow between branches. 

As genetic understanding develops, it will be incorporated into basic breeding programs that are concerned with such characteristics as yield, growth habit, insect and disease resistance, flavor, and texture. These programs will be most effective if present ambient ozone and other oxidant concentrations do not increase. 

When three of the oxygens in the tetrahedra are shared (Si O ratio = 2 5), the complex ions that form take on a sheetlike configuration. The sheets can be stacked, and the associated cations are found between the sheets. Micas and clays are sheet-structure minerals with distinctive habits and physical properties, that reflect the planar silicate sheet structure (Fig. 2.1G). These normally platey minerals may also occur with fibrous-growth habits. The special crystal chemistry that produces such a distinctive habit is discussed later. 

In a recent paper (70 Hartman studies the effect of surface relaxation on the habit of corundum and hematite. The habits observed on natural and synthetic crystals of these systems did not agree with calculated relaxed equilibrium or growth habits. Hartman concluded that these observations could be understood by invoking specific solvent adsorption on (111) faces. 

Results are shown in Table 1 and Figure 9. Hie corresponding growth habit (R att) is platelike with (100, (011) and (001) planes. This seems in apparent disagreement with a report (20) on the habit of ethyl acetate grown adipic acid (b-axis elongated with (001), (100), (110) and (011). The corresponding relative areas of the faces are ... 

BaC03 BaTi04 CaS04 growth habit citiates, SO , elevated temp. 

We have mentioned above the tendency of atoms to preserve their coordination in solid state processes. This suggests that the diffusionless transformation tries to preserve close-packed planes and close-packed directions in both the parent and the martensite structure. For the example of the Bain-transformation this then means that 111) -> 011). (J = martensite) and <111> -. Obviously, the main question in this context is how to conduct the transformation (= advancement of the p/P boundary) and ensure that on a macroscopic scale the growth (habit) plane is undistorted (invariant). In addition, once nucleation has occurred, the observed high transformation velocity (nearly sound velocity) has to be explained. Isothermal martensitic transformations may well need a long time before significant volume fractions of P are transformed into / . This does not contradict the high interface velocity, but merely stresses the sluggish nucleation kinetics. The interface velocity is essentially temperature-independent since no thermal activation is necessary. 

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