Use Of Interference Microscopy Research Articles

Assessing one-dimensional diffusion in nanoporous materials from transient concentration profiles

The use of interference microscopy has enabled the direct observation of transient concentration profiles generated by intracrystalline transport diffusion in nanoporous materials. The thus accessible intracrystalline concentration profiles contain a wealth of information which cannot be deduced by any macroscopic method. In this paper, we illustrate five different ways for determining the concentration-dependent diffusivity in one-dimensional systems and two for the surface permeability. These methods are discussed by application to concentration profiles evolving during the uptake of methanol by the zeolite ferrierite and of methanol by the metal organic framework (MOF) manganese(II) formate. We show that the diffusivity can be calculated most precisely by means of Fick's 1st law. As the circumstances permit, Boltzmann's integration method also yields very precise results. Furthermore, we present a simple procedure that enables the estimation of the influence of the surface barrier on the overall uptake process by plotting the boundary concentration versus the overall uptake.

Inhomogeneous Distribution of Water Adsorbed under Low Pressure in CrAPO-5 and SAPO-5: An Interference Microscopy Study

Intracrystalline concentration profiles of water, adsorbed in large crystals of CrAPO-5 and SAPO-5 under equilibrium with water vapor at 1 and 20 mbar, were determined with use of interference microscopy. At lower pressure, the profiles reveal highly inhomogeneous distributions of intracrystalline water in both crystal types. This effect is attributed to structural heterogeneity of the crystals. Its possible relation to the progress of the crystal growth process is considered. Under the vapor pressure of 20 mbar, the water molecules are homogeneously distributed over the crystals. In this case, the pore volume is saturated with liquid-like water. The structural heterogeneity has been found to have a low or no influence on the final uptake level of the crystals.

The refractive index and dry mass distribution of mammalian erythrocytes

SUMMARYQuantitative microscopical methods are now of outstanding importance in the diagnosis and assessment of mammalian red blood cells.After release from the erythropoetic organs, all red blood cells in the peripheral blood of mammals pass through the reticulocyte stage before becoming mature erythrocytes. Therefore, the determination of reticulocyte number is used as an index of erythropoetic activity in clinical hæmatology.The corpuscular solid concentration, the corpuscular dry weight, the osmotic resistance and the size of red blood cells can be determined by use of microscopical methods. For the determination of the corpuscular solid concentration of erythrocytes, cell refractometry by the use of phase‐contrast microscopy has proved to be a very sensitive and accurate method. The dry weight of single erythrocytes may likewise be obtained by the use of interference microscopy with relatively high accuracy. Both of these methods might also be of use in clinical hæmatology.In the experimental work described in this paper, both methods mentioned above are used to answer the question: whether and under what conditions the refractive index as a criterion of measurement of the solid concentration and the relative dry weight can be determined separately for reticulocytes and erythrocytes from the same blood sample by use of microscopical methods alone. The frequency distributions of refractive indices and relative dry weights determined on human reticulocytes and mature erythrocytes show significantly lower mean values for the reticulocyte generation in accordant with findings published by other authors and obtained by use of sometimes entirely different methods. The additional information gained by the determination of the frequency distribution of refractive index and dry weight of reticulocytes and mature erythrocytes separately in a blood sample and the necessity for simplifying and automating such methods for hæmatological diagnosis are discussed.

Studies on the kinetics of alkaline phosphatase reaction in Ehrlich ascites tumour cells with the use of interference microscopy.

Mittels Interferenzmikroskopie wurde die Prazipitationsrate des Calciumphosphats in Ehrlich Ascites-Tumorzellen gemessen und die Beeinflussung der alkalischen Phosphataseaktivitat durch diverse Faktoren untersucht.

USE OF INTERFERENCE MICROSCOPY FOR THE MINERALOGICAL ANALYSIS OF SAMPLES OF AIRBORNE DUST OBTAINED WITH THE THERMAL PRECIPITATOR.

Use of Interference Microscopy for the Mineralogical Analysis of Samples of Airborne Dust Obtained with the Thermal Precipitator

An interferometric study of the anhydrous nuclear mass of exfoliated cells from experimental cervical cancer

An interferometric study of the anhydrous nuclear mass of exfoliated cells from experimental cervical cancer

An evaluation of the qualitative use of interference microscopy in cytology.

An evaluation of the qualitative use of interference microscopy in cytology.

A quantitative cytochemical method for estimating alkaline phosphatase activity

By the use of interference microscopy the rate of deposition of calcium phosphate, resulting from enzyme activity, can be measured quantitatively. This provides a quantitative measure of enzyme activity at individual cellular sites. By this method, studies have been made of the effect of variation in substrate concentration, pH, temperature and calcium-ion concentration on the enzymatic activity of the brush border regions of rat-kidney tubules and of duodenal epithelium. Some observations of cell nuclei have also been made. Under standard conditions of incubation (Danielli 1953) at least 97⋅5% of the phosphate ions liberated in a kidney section are precipitated, and once precipitated the calcium phosphate does not redissolve. Under standard conditions of incubation no loss of enzyme activity from brush borders of kidney and duodenum could be detected.