A PRECISE METHOD, WITH DETAILED CALIBRATION FOR THE DETERMINATION OF ABSORPTION COEFFICIENTS; THE QUANTITATIVE MEASUREMENT OF THE VISIBLE AND ULTRAVIOLET ABSORPTION SPECTRA OF ALPHA CAROTENE, BETA CAROTENE, AND LYCOPENE

Two new morphological measurements based on digital image analysis, CoContinuity and CoContinuity Balance, have been developed and implemented for quantitative measurement of morphology in polymer blends. The morphology of polymer blends varies with phase ratio, composition and processing. A typical morphological evolution for increasing phase ratio of polymer A to polymer B starts with discrete domains of A in a matrix of B (A/B < 1), moves through a cocontinuous distribution of A and B (A/B ≈ 1) and finishes with discrete domains of B in a matrix of A (A/B > 1). For low phase ratios, A is often seen as solid convex particles embedded in the continuous B phase. As the ratio increases, A domains begin to evolve into irregular shapes, though still recognizable as separate domains. Further increase in the phase ratio leads to A domains which extend into and surround the B phase while the B phase simultaneously extends into and surrounds the A phase.

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Estimation of chlorophyll content by absorption spectra of native Spirulina platensis cells

Issues of modern algology (Вопросы современной альгологии) ◽

10.33624/2311-0147-2020-1(22)-25-33 ◽

2020 ◽

pp. 25-33

Author(s):

Leonid E. Paramonov

Keyword(s):

Chlorophyll Content ◽

Chlorophyll A ◽

Absorption Spectra ◽

Spirulina Platensis ◽

Intracellular Concentration ◽

Absorption Coefficients

A method for retrieving the absorption coefficients of Spirulina platensis pigments using absorption spectra of native cells and excluding the use of extracts is considered. Estimates of the intracellular concentration of chlorophyll a, С-phycoerythrin, С- phycocyanin and allophycocyanin in native cells are discussed.

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Nauwkeurige methode voor de aanwasbepaling van het grondvlak met behulp van de Pressler-boor

Silva Gandavensis ◽

10.21825/sg.v12i0.1009 ◽

1968 ◽

Vol 12 ◽

Author(s):

R. Goossens

Keyword(s):

Basal Area ◽

Precise Determination ◽

Maximum Diameter ◽

Precise Method ◽

Maximum Radius ◽

The Core ◽

Two Parameters

A precise method for the determination of the increment of the basal area using the PressIer bore. Refering to previous research showing that the basal area of the corsica pine could be characterized by an ellips, we present in this paper a precise method for the determination of the increment of the basal area. In this method we determine the direction of the maximum diameter, we measure this diameter and we take a core in one of the points of tangency of the caliper with the measured tree. The determination of the diameter perpendicular to the maximum diameter finishes the work wich is to be done in the forest. From the classical measurements effectuated on the core and from the measured diameters we can then determine the form (V) and the excentricity (e). Substituting these two parameters in the formula 2 or 2', we can also calculate the error of a radius measured on the core with respect to the representative radius, This error with them allow us to correct the measured value of the minimum or the maximum radius and we will be able to do a precise determination of the increment.

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