Pore microgeometry analysis in low-resistivity sandstone reservoirs

The objective of this work is to analyse the pore microgeometry and its effect on petrophysical properties in six low-resistivity sandstone reservoirs by combining a 2D quantitative petrographic image analysis (PIA) and 3D petrophysical tools. The classic petrophysical tools enable the measurement of different classic reservoir properties such as specific surface area, average pore diameter, pore size distribution, macroporosity and microporosity, capillary pressure versus saturation, pore chamber–pore throat diameter ratio, electrical properties and permeability. The petrographic image analysis quantifies pore microgeometry in more than four orders of magnitude, from submicron to millimeter scale. Chloritic low-resistivity sandstones show dual porosity structure defined as chloritic texture. The pore microgeometrical parameters measured by petrographic image analysis allow one to model different reservoir properties such as capillary pressure, permeability and electrical behaviour. The results obtained in these models show that pore microgeometry plays an important role in the physical properties of low-resistivity sandstone reservoirs.     

PROTEIN PRECIPITATION DURING WORT BOILING: QUALITY ASPECTS OF DIMINISHED WORT BOILING TIMES OF BREWS PREPARED FROM PROANTHOCYANIDIN-FREE OR REGULAR RAW MATERIALS

When using proanthocyanidin-free materials for the production of beer, a reduction of the wort boiling time can be considered. In worts prepared with regular malt and tannin-free hop extract there is a continuous precipitation of the malt flavanoids while in brews prepared from proanthocyanidin-free malt and regular hops there is a simultaneous extraction and removal of the hop flavanoids leading to constant levels of these hop flavanoids. The results also show that the level of Kjeldahl nitrogen in worts boiled with hops will be the same as that in worts boiled with n-hexane tannin-free hop extracts. These results and the fact that more protein precipitates in brews containing no malt or hop proanthocyanidins suggest that, unlike what is the case during the development of beer haze, polyphenols are not necessary for an effective protein precipitation during wort boiling.     

Thermodynamic and spectroscopic measurements of the electron-hole drop binding energy in Ge: An old problem revisited

One can expect to get the electron-hole (EHD) binding energy φ either from spectroscopic or from threshold measurements. While the value obtained by the former is in excellent agreement with theory, the results given by the latter did not seem to lead to φ in a simple way. We present here new optical threshold studies in which we think that the right conditions to obtain a direct thermodynamic measurement of φ have been mastered. Besides, our results present novel features like a sharp jump of the EHD luminescence at threshold above 2.4 K and observation of hysteresis in the whole temperature range of our work.     

Pulmonary effects of chronic exposure to airborne cadmium

In haemoglobinometry grave errors are still being made even though an internationally accepted standardized method is available for the determination of the haemoglobin content of blood. Up to the present only haemiglobincyanide reference solutions have been available on a wide scale to check the measuring stage of the standardized haemiglobincyanide method. These reference solutions are shown to remain stable, under proper storage conditions, for more than 10 years. Concentrated haemoglobin solutions have become available recently, offering the possibility to control the dilution and conversion steps of the haemiglobincyanide method. Such a solution is shown to remain stable, under proper storage conditions, for at least a year. Using both haemiglobincyanide reference solutions and concentrated haemoglobin solutions, as well as having the possibility of checking the cyanide content of the reagent used, an acceptable intra-laboratory control program may now be set up.     

Polyvinylpyrrolidone-storage disease. Light microscopical, ultrastructural and chemical verification

The light and electron microscopical findings in the polyvinylpyrrolidine-storage disease are reported on the basis of biopsies of skin, striated muscle, bone marrow and liver from one patient and a subcutaneous nodule from another patient. Both patients suffer from diabetes insipidus and have been treated for several years with Insipidin retard, which contains polyvinylpyrrolidone (PVP) as the retarding agent. Deposits of PVP have been demonstrated in all the tissues examined and can easily be recognized by certain staining qualities. The combination of haematoxylin-eosin, elastin (Weigert), alkaline Congo red and Sirius red for amyloid and PTAH is specially to be recommended. The ultrastructural findings consist of intracellular vacuoles containing a granular material and probably representing lysosomes. The final identification of the nature of the deposits has been made by spectrophotometric analysis. The suspicion of a case of PVP-storage disease should result in a skin biopsy which usually is sufficient for the diagnosis.     

Inactivation of Semliki Forest Virus in aerosols

Purified Semliki forest virus in aerosols is inactivated rapidly at 40% and above 70% relative humidity. At all humidities tested the decay of virus infectivity runs parallel with the decrease in hemagglutination activity, whereas the biological integrity of the virus ribonucleic acid is preserved. Also, free infectious ribonucleic acid is stable after spraying at all relative humidities. Evidence is presented for the hypothesis that above 20% relative humidity, virus inactivation in aersols is mainly due to surface-dependent factors, damaging the virus coat.     

Chances of reducing the formation of immune antibodies after massive transfusions in open heart surgery (author's transl)

Children, young people and women at the age of possible maternity form the majority of patients operated by extracorporal circulation. A longterm planning of these operations should also have donor in call, who are compatible with the patients' Rh groups and Kell antigens. Having practiced such a selection of donors we succeeded in reducing the formation of immune antibodies. 6 out of 330 patients had antibodies, but 4 had been sensibilized before operation. In the case of the other 2 it would not be excluded that they might have been immunized a long time ago. We emphasize the importance of hemodilution, strict indication of every postoperative therapy with red cells and the autologous transfusion.