Results 241 to 250 of about 98,754 (272)

SLIME SUBSTANCE AND STRANDS IN SIEVE ELEMENTS

American Journal of Botany, 1964
Studies of the secondary phloem of 6 species of woody dicotyledons revealed that slime is not normally dispersed throughout the vacuole of mature sieve elements, but occurs in the form of discrete strands that traverse the cell and run from cell to cell through the sieve‐plate pores. As many as 5 fine strands, each measuring less than 0.5μ in diameter,
R. F. Evert, W. F. Derr
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Sieve Elements: The Favourite Habitat of Phytoplasmas

2018
The sieve elements are the only plant compartments, where phytoplasmas can survive and propagate. Therefore, this chapter is focussed on the specific molecular and cell-biological properties of the sieve element. Sieve element-companion cell complexes arise from (pro)cambial mother cells induced by key genes known to be decisive for sieve-element ...
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Sieve‐Element Characters of the Proteaceae and Elaeagnaceae: Nuclear Crystals, Phloem Proteins and Sieve‐Element Plastids

Botanica Acta, 1995
AbstractThe sieve‐element characters of 34 species from the Proteaceae and Elaeagnaceae have been studied by transmission electron microscopy. While nondispersive protein bodies and dispersive P‐protein are typical components of both families, specific forms and/or their distinctive origin accentuate some taxa.
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Microfilaments in pores between frozen-etched sieve elements

Planta, 1968
Sieve tubes were frozen before being cut from plants and were prepared for electron microscopy by freeze-etching. Structures that may be interpreted as filaments appeared in and near pores through sieve plates. Their presence suggests that filaments seen in sieve-pores prepared chemically may be there normally.
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Modeling the Hydraulic Conductivity of Phloem Sieve Elements

2019
Phloem transport of photoassimilates affects nearly all aspects of plant life, from growth to reproduction. This chapter summarizes mathematical techniques to quantify the impact of sieve element anatomy on phloem transport processes.
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Novel diffractive optical element: binary photon sieve

Optical Engineering, 2011
In this paper, we developed a novel photon sieve consisting of a large number of precisely positioned holes distributed according to an underlying Fresnel zone plate (FZP) geometry, while the holes at transparent and opaque circular rings of the FZP have a π phase shift.
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Recent Advances in Tetra- (Ti, Sn, Zr, Hf) and Pentavalent (Nb, V, Ta) Metal-Substituted Molecular Sieve Catalysis

Chemical Reviews, 2023
Steven L Suib, Jan Přech
exaly  

Organic molecular sieve membranes for chemical separations

Chemical Society Reviews, 2021
Meidi Wang, Xu Liang, Jinqiu Yuan
exaly  

Advanced carbon molecular sieve membranes derived from molecularly engineered cross-linkable copolyimide for gas separations

Nature Materials, 2022
William J Koros
exaly  

Reducing Water Activity by Zeolite Molecular Sieve Membrane for Long‐Life Rechargeable Zinc Battery

Advanced Materials, 2021
Huijun Yang, Yu Qiao, Zhi Chang
exaly