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Vicat softening temperature or Vicat hardness is the determination of the softening point for materials that have no definite melting point, such as plastics. It is taken as the temperature at which the specimen is penetrated to a depth of 1 mm by a flat-ended needle with a 1 mm 2 circular or square cross-section.
Lacking photosynthetic pigments, leucoplasts are located in non-photosynthetic tissues of plants, such as roots, bulbs and seeds. They may be specialized for bulk storage of starch , lipid or protein and are then known as amyloplasts , elaioplasts , or proteinoplasts (also called aleuroplasts) respectively.
A Soxhlet extractor is a piece of laboratory apparatus [1] invented in 1879 by Franz von Soxhlet. [2] It was originally designed for the extraction of a lipid from a solid material. Typically, Soxhlet extraction is used when the desired compound has a limited solubility in a solvent, and the impurity is insoluble in that solvent. It allows for ...
The softening point is the temperature at which a material softens beyond some arbitrary softness. [1] It can be determined, for example, by the Vicat method (ASTM-D1525 or ISO 306), Heat Deflection Test (ASTM-D648) or a ring and ball method (ISO 4625 or ASTM E28-67/E28-99 or ASTM D36 or ASTM D6493 - 11 or JIS K 6863).
Plant anatomy or phytotomy is the general term for the study of the internal structure of plants.Originally, it included plant morphology, the description of the physical form and external structure of plants, but since the mid-20th century, plant anatomy has been considered a separate field referring only to internal plant structure.
As two tangents to the circle at the ends of a chord 3d/8 long intersect at 136°, it was decided to use this as the included angle between plane faces of the indenter tip. This gives an angle from each face normal to the horizontal plane normal of 22° on each side.
Plants have two major organs systems. Vascular plants have two distinct organ systems: a shoot system, and a root system. The shoot system consists stems, leaves, and the reproductive parts of the plant (flowers and fruits). The shoot system generally grows above ground, where it absorbs the light needed for photosynthesis. The root system ...
Although plant morphology (the external form) is integrated with plant anatomy (the internal form), the former became the basis of the taxonomic description of plants that exists today, due to the few tools required to observe. [2] [3] Many of these terms date back to the earliest herbalists and botanists, including Theophrastus.