Roof plate

Spinal commissural axons are shown to be guided toward the ventral midline by a chemoattractant from the floor plate. However, this can only explain the guidance mechanism near the ventral midline, raising the possibility that there may be another guidance mechanism. 

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Tank Roof. The roof of a vertical cylindrical tank is treated like a building stmcture and uses the same basic rules as the building codes. For example, the API codes require a roof to be designed for the dead load plus a 122-kg/m (25-lb /ft ) Hve load. The minimum fabrication thickness of roof plates is 3/16 in. (4.8 mm). 

For tank internal pressures that do not exceed the weight of the roof plates, most tanks have conical roofs because these are the simplest and most cost-effective. When the pressure is increased beyond the weight of the roof plates, the roof-to-sheU area goes into hoop compression. A small portion of the roof, the roof-to-sheU angle, and the top few centimeters of the sheU act as a compression ring to resist the unbalanced forces from internal pressure on the conical roof. The internal design pressure for this case may be... 

Liem, K. J., Tremml, G., Roelink, H. and Jessel, T. A role for the roof plate and its resident TGFP-related proteins in neuronal patterning in the dorsal spinal cord. Cell 91 127-138, 1997. 

Vertical tanks. Those supported above ground are made with dished or conicai bottoms. Flat bottomed tanks rest on firm foundations of oiled sand or concrete. Supported flat bottoms usually are 1/4 in. thick. Roof plates are 3/16 in. thick. Special roof... 

The tank is specified to have a capacity of 1950 m3. This figure is the sum of one week production of nitric acid (1500 m3) plus an extra 450 m3. This extra 450 m3 capacity will be the normal tank operating level and is available for product sales to external markets. This represents approximately 20 standard road-tanker loads. The dimensions of the tank represent a standard specification available through the Denver Company (United States). The tank internal diameter is 15.2 m and the tank height required is 10.7 m. The internal and external pressure loads require a wall, base and roof plate thickness of 16 mm (a standard plate thickness available through BHP, Australia) to meet the Australian design code for pressure vessels (AS1 210). This thickness gives a 100% safety factor over the maximum anticipated stresses. 

A tank must have other qualities for successful explosion venting. The cone roof slope must not exceed 1 in 6 and should preferably be no more than 3/4 in 12. If the roof is supported by roof rafters the roof plates must not be attached to the rafters but must simply rest on the rafters. Roof lifting must not be hampered by railings or other structures above the roof. The roof should be able to lift, unhampered, to a height sufficient to give a peripheral open area equal to 1 A times the tank cross section. The roof should be as thin as possible preferably not over 6 mm (1/4 in). Both roof release pressure and roof weight per unit area should be as small as possible to minimize energy development before roof lift. 

The compression subsets comprise the upper roller assembly and the lower roller assembly. The upper roller assembly is located on the roof plate of the press and utilizes an adjustment system for the regulation of the insertion depth. The lower roller assembly is located on the underside of the die table and utilizes a device for the regulation of the tablet edge thickness. 

Dimensions Capacity Bottom Plates Shell Plates (Butt Welded) Top Angle Roof Plates... 

Snow, D. M., Steindler, D. A., and Silver, J., Molecular and cellular characterisation of the glial roof plate of the spinal cord and optic tectum. A possible role for a proteoglycan in the development of an axonal barrier, Dev. Biol., 138, 359, 1990. 

Kevin J. Lee, Paula Dietrich and Thomas M. Jessell, Genetic ablation reveals that the roof plate is essential for dorsal interneuron specification. Nature, 403 (2000), 734—740. 

Figure 8. Turning of DAPms axons away from floor explants in collagen gel culture. (A) Diagrammatic representation of coronal view of the mesencephalon showing explant origins (hatched areas). RR roof plate AR alar plate VAR ventral alar plate BR basal plate SL, sulcus limitans, the AR/BR boundary. (B, D) Diagrams showing...

Augsburger, A., Schuchardt, A., Hoskins, S., Dodd, J. and Buder, S. (1999). BMPs as mediators of roof plate repulsion of commissural neurons. Neuron 24,127-141. Bernhardt, R.R., Nguyen, N. and Kuwada, J.Y. (1992). Growthcone guidance by floor plate cells in the spinal cord of zebrafish embryos. Neuron 8, 869-882. Bernhardt, R.R., Patel, C.K., Wilson, S.W. and Kuwada, J.Y. (1992). Axonal trajectories and distribution of GABAergic spinal neurons in wild-type and mutant zebrafish lacking floor plate cells. J. Comp. Neurol. 326, 263—272. 

Dai J, et al. 2004. Elastic analysis of suspended triangle roof plate with curve side on the end of sublevel caving mining face. Chinese Journal of Rock Mechanics and Engineering, 23 (2) 16-21. 

From Figure 5 it can be seen that the temperature trends inside the roof and bottom plate are different. The temperature inside the roof plate was lower than the ambient temperature firstly, but which start to be higher than ambient temperature at about 13 00. At the end, the temperature inside the roof plate goes up feebly, while the ambient temperature decline, and the average diurnal range of temperature inside the roof plate was 8.6 C. 

Composite elements with Portland cement matrices and textile reinforcement have been used for some time as thin roof plates, partition walls, cladding, and the like. Some discussion of textile reinforcement is presented in Section 5.9. As well as systems of plane fabrics, three-dimensional (3D) reinforcement is also manufactured and there have been tests of elements with 3D carbon fibre reinforcement (Zia et al. 1992). 

Shki ls with Self-supportivi Roofs. A seIf-sup M r(-ing roof is one which is. supported only on its peripfiery, without added structural support. Such roofs cause a compressive stress in the roof plates, wliich i.s transferred to the shell as hoop tension. A stiflfening angle should be ai ded to the top shell course at the junction of the roof and shell to al orb the stress as a tensile load. The forces acting on the ring are shown in Fig, 3.19. 

In applying Eq. 3.23 credit may taken for the cross-s ional area of the shell and roof plates within a distiince 16 tones their thickness from the stiffening angle. In otter words, tJte sum of these areas must be equal to or grater than (DV3000 sin 0) for cone-roof instruction. 

E<(tmiion 4.6 is the equation sfiertlied by. PI Standard 12 C for. self-supporlingct iicnI roofs. It should Ije emphasized that the derivation of the constant is based upon selerled ri of loads and fig-in, roof plate thicknesses and... 

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