WATER CONTENT MEASURING METHOD OF RECLAIMED GYPSUMS DERIVED FROM WASTE PLASTERBOARDS FOCUSING ON SOLUBILITY OF WATER TO GLYCEROL

Author(s):  
Hiroaki SANO ◽  
Hidekazu MORIOKA ◽  
Hiroshi KAWAMITSU ◽  
Mikio YAMADA ◽  
Nozomu KOTAKE ◽  
...  
Biologia ◽  
2009 ◽  
Vol 64 (3) ◽  
Author(s):  
Eszter Tóth ◽  
Sándor Koós ◽  
Csilla Farkas

AbstractThe aim of this study was to evaluate a measuring technique for determining soil CO2 efflux from large soil samples having undisturbed structure under controlled laboratory conditions. Further objectives were to use the developed measuring method for comparing soil CO2 efflux from samples, collected in three different soil management systems at various soil water content values. The experimental technique was tested and optimised for timing of sampling by taking air samples after 1, 3 and 6 hours of incubation. Based on the results, the incubation time was set to three hours. The CO2 efflux measured for different soil management systems was the highest in the no-till and the lowest in the ploughing treatment, which was in accordance with measurements on accessible organic carbon for microbes. An increase in CO2 efflux with increasing soil water content was found in the studied soil water content range. Our results indicate that soil respiration rates, measured directly after tillage operations, can highly differ from those measured long after.


2015 ◽  
Vol 1124 ◽  
pp. 203-208 ◽  
Author(s):  
Miroslav Luňák ◽  
Ivo Kusák

Impedance spectroscopy (IS) is a non-destructive testing (NDT) method ranking in the electrical engineering measuring method group. It outputs data providing information on material electric and dielectric properties. Microscopically inhomogeneous materials are frequently used in the building industry. Unfortunately, the impedance spectroscopy results and their characterization on the basis of this method are not unambiguous. The frequency spectrum behavior of Cetris-basic specimens was studied by means of the NDT impedance spectroscopy method for various water content values. A stress cycle with defined absolute water content values is described. Influences of potential dielectric losses and the predominance of the polarization and conductivity components in various regions of the impedance spectrum are described for various water content values.


Author(s):  
Songquan Sun ◽  
Richard D. Leapman

Analyses of ultrathin cryosections are generally performed after freeze-drying because the presence of water renders the specimens highly susceptible to radiation damage. The water content of a subcellular compartment is an important quantity that must be known, for example, to convert the dry weight concentrations of ions to the physiologically more relevant molar concentrations. Water content can be determined indirectly from dark-field mass measurements provided that there is no differential shrinkage between compartments and that there exists a suitable internal standard. The potential advantage of a more direct method for measuring water has led us to explore the use of electron energy loss spectroscopy (EELS) for characterizing biological specimens in their frozen hydrated state.We have obtained preliminary EELS measurements from pure amorphous ice and from cryosectioned frozen protein solutions. The specimens were cryotransfered into a VG-HB501 field-emission STEM equipped with a 666 Gatan parallel-detection spectrometer and analyzed at approximately −160 C.


Author(s):  
R.D. Leapman ◽  
S.Q. Sun ◽  
S-L. Shi ◽  
R.A. Buchanan ◽  
S.B. Andrews

Recent advances in rapid-freezing and cryosectioning techniques coupled with use of the quantitative signals available in the scanning transmission electron microscope (STEM) can provide us with new methods for determining the water distributions of subcellular compartments. The water content is an important physiological quantity that reflects how fluid and electrolytes are regulated in the cell; it is also required to convert dry weight concentrations of ions obtained from x-ray microanalysis into the more relevant molar ionic concentrations. Here we compare the information about water concentrations from both elastic (annular dark-field) and inelastic (electron energy loss) scattering measurements.In order to utilize the elastic signal it is first necessary to increase contrast by removing the water from the cryosection. After dehydration the tissue can be digitally imaged under low-dose conditions, in the same way that STEM mass mapping of macromolecules is performed. The resulting pixel intensities are then converted into dry mass fractions by using an internal standard, e.g., the mean intensity of the whole image may be taken as representative of the bulk water content of the tissue.


Sign in / Sign up

Export Citation Format

Share Document