Moisture Quenching of Solid-Matrix Phosphorescence on Hydrophilic and Partially Hydrophobic Filter Papers

2002 ◽  
Vol 56 (10) ◽  
pp. 1368-1375 ◽  
Author(s):  
Amanda H. Ackerman ◽  
Robert J. Hurtubise
Keyword(s):  
Exponential Function ◽  
Filter Paper ◽  
Empirical Equation ◽  
Solid Matrix ◽  
Intensity Data ◽  
Moisture Adsorption ◽  
Wide Range ◽  
Simple Exponential Function ◽  
Filter Papers ◽  
Adsorbed Moisture

A detailed investigation was undertaken to determine the important parameters that were responsible for the solid-matrix phosphorescence (SMP) moisture quenching of phosphors adsorbed in Whatman No. 1 (hydrophilic) and Whatman 1PS (partially hydrophobic) papers. The three phosphors used were phenanthrene, perdeuterated phenanthrene, and benzo[ e]pyrene. Both SMP lifetime and SMP intensity data were obtained over a wide range of adsorbed moisture. In addition, moisture isotherms were obtained for the No. 1 and 1PS papers. The SMP lifetimes of phenanthrene and benzo[ e]pyrene were independent of the amount of adsorbed moisture on both the No. 1 and 1PS papers. However, the SMP lifetimes of perdeuterated phenanthrene on No. 1 and 1PS papers were dependent on the extent of the adsorbed moisture. The changes in the SMP intensities as a function of adsorbed moisture for phenanthrene, benzo[ e]pyrene, and perdeuterated phenanthrene on No. 1 paper could be modeled by a simple exponential function with phenanthrene and benzo[ e]pyrene giving better correlations compared to perdeuterated phenanthrene. The change in the modulus of filter paper samples with moisture adsorption was a major factor in causing the SMP intensity to decrease. The decrease in the SMP intensities with moisture adsorption for the three phosphors adsorbed on 1PS paper did not correlate with the simple Stern–Volmer model and several other quenching models discussed in the literature. Thus, these data were fit to a relatively simple empirical equation. The results showed that the SMP quenching phenomena for the three phosphors on No. 1 paper and on 1PS paper were considerably different.

Dynamic and Solid-Matrix Quenching by Moisture in Solid-Matrix Phosphorescence with Filter Paper

1994 ◽  
Vol 48 (10) ◽  
pp. 1242-1248 ◽  
Author(s):  
Jie Chen ◽  
S. W. Tjioe ◽  
Robert J. Hurtubise
Keyword(s):  
Filter Paper ◽  
Room Temperature ◽  
Solid Matrix ◽  
Dynamic Quenching ◽  
Phosphorescence Lifetime ◽  
Phosphorescence Intensity ◽  
Wide Range ◽  
Intensity Ratios ◽  
Monolayer Coverage ◽  
Adsorbed Moisture

The room-temperature solid-matrix phosphorescence intensity ratios behaved very differently than the phosphorescence lifetime ratios for 4-phenylphenol, protonated benzo( f)quinoline, and two tetrols adsorbed on filter paper over a wide range of wt % adsorbed moisture. The changes in phosphorescence intensity ratios and lifetime ratios were related to regions before the monolayer coverage of water and beyond monolayer coverage of water on filter paper. An equation was obtained that describes the changes in the phosphorescence intensity ratio as a function of phosphorescence lifetime ratio and an exponential expression that included the wt % of adsorbed moisture. This equation defined both dynamic and solid-matrix quenching of phosphorescence by adsorbed moisture. The changes in the phosphorescence lifetime ratios were readily related to wt % adsorbed moisture by the use of a dynamic quenching model.

scholarly journals Well-Dispersed Silver Nanoparticles on Cellulose Filter Paper for Bacterial Removal

Nanomaterials ◽  
2021 ◽  
Vol 11 (3) ◽  
pp. 595
Author(s):  
Hsiu-Wen Chien ◽  
Ming-Yen Tsai ◽  
Chia-Jung Kuo ◽  
Ching-Lo Lin
Keyword(s):  
Silver Nanoparticles ◽  
Filter Paper ◽  
X Ray Diffraction ◽  
Bacterial Reduction ◽  
Treatment Technology ◽  
Bacterial Removal ◽  
Contaminated Drinking Water ◽  
Gravity Driven ◽  
Filter Papers ◽  
Cellulose Filter

In this study, a polydopamine (PDA) and polyethyleneimine (PEI)-assisted approach was developed to generate well-distributed PDA/PEI/silver (PDA/PEI/Ag) nanocomplexes on the surfaces of commercial cellulose filter papers to achieve substantial bacterial reduction under gravity-driven filtration. PDA can bind to cellulose paper and act as a reducer to produce silver nanoparticles (AgNPs), while PEI can react with oxidative dopamine and act as a dispersant to avoid the aggregation of AgNPs. The successful immobilization of PDA/PEI/Ag nanocomplexes was confirmed by scanning electron microscopy (SEM), X-ray diffraction (XRD), and Fourier transform infrared spectroscopy (FTIR). Staphylococcus aureus (S. aureus) and Escherichia coli (E. coli) were used as pathogen models to test the efficacy of the PDA/PEI/Ag nanocomplex-incorporated filter papers. The PDA/PEI/Ag nanocomplex-incorporated filter papers provided a substantial bacterial removal of up to 99% by simple gravity filtration. This work may be useful to develop a feasible industrial production process for the integration of biocidal AgNPs into cellulose filter paper and is recommended as a local-condition water-treatment technology to treat microbial-contaminated drinking water.

Measurement of Extracellular Fluid Volume of Nephrectomized Dogs With Mannitol, Sucrose, Thiosulfate and Radiosulfate

1956 ◽  
Vol 185 (1) ◽  
pp. 179-184 ◽  
Author(s):  
Patrick J. Mulrow ◽  
Herbert M. Oestreich ◽  
Roy C. Swan
Keyword(s):  
Exponential Function ◽  
Extracellular Fluid ◽  
Volume Of Distribution ◽  
Fluid Volume ◽  
Extracellular Fluid Volume ◽  
Simple Exponential Function ◽  
Volumes Of Distribution

Volumes of distribution of mannitol, sucrose, thiosulfate and radiosulfate have been measured simultaneously in nephrectomized dogs. The volume of distribution of each substance is reproducible when the substance is reinfused 6 hours later. There appears to be no increase in the extracellular fluid volume during this interval as a result of the nephrectomy. The logarithm of the concentration of mannitol, sucrose and radiosulfate continues as a simple exponential function of time from the 3rd to 30th hour after their infusion. The volumes of distribution of mannitol and radiosulfate reflect increments in extracellular fluid with fair accuracy, while the sucrose distribution measures only 72% of a 1-liter expansion of extracellular fluid. There are serious limitations in the application of thiosulfate distribution to such measurements.

Hydrophobic and Oleophilic Filter Paper for Oil/Water Separation

2019 ◽  
Vol 798 ◽  
pp. 385-390
Author(s):  
Sunisa Jindasuwan ◽  
Sitthisuntorn Supothina
Keyword(s):  
Contact Angle ◽  
Free Energy ◽  
Surface Free Energy ◽  
Water Contact Angle ◽  
Filter Paper ◽  
Diesel Oil ◽  
Selective Removal ◽  
Water Contact ◽  
Water Separation ◽  
Filter Papers

The separation of oil from water is significance for environmental de-pollution application. To obtain selectivity of liquid, filter papers were coated to bear highly hydrophobic and oleophilic functionality that can allow only oils to pass through them. The coating solutions were prepared by mixing poly(methylhydro siloxane, PMHS) and fumed silica at various proportions. To determine an optimum coating condition, properties of the treated filter papers were investigated by measuring water contact angle and surface free energy, examining surface morphology and testing for selective removal of diesel oil from water. The optimum coating solution was at the PMHS:fumed silica weight ratio of 1.25:1.00. The treated filter paper exhibited high hydrophobicity with water contact angle of 142.80 ± 0.36 degrees and surface free energy of 0.78 mJ/m2. In addition, it exhibited high selective removal of diesel oil from water with oil absorption capacity of 2.3 g/g.

scholarly journals Colorimetric Measurement of Glycosylated Protein in Whole Blood, Red Blood Cells, Plasma and Dried Blood

1984 ◽  
Vol 21 (6) ◽  
pp. 477-483 ◽  
Author(s):  
J Eross ◽  
D Kreutzmann ◽  
M Jimenez ◽  
R Keen ◽  
S Rogers ◽  
...  
Keyword(s):  
Red Blood Cells ◽  
Filter Paper ◽  
Whole Blood ◽  
Blood Cells ◽  
Colorimetric Method ◽  
Diabetic Control ◽  
Exchange Chromatography ◽  
Patient Acceptance ◽  
Colorimetric Measurement ◽  
Filter Papers

A colorimetric method for the measurement of whole-blood glycosylation (WBG), glycosylated haemoglobin in red blood cells (GHb), glycosylated plasma protein (GPP) and dried-blood glycosylation (DBG) is described which is rapid, inexpensive and precise. GHb correlated well with HbA1 measured by cation-exchange chromatography and was also correlated with WBG, DBG and GPP. DBG, which showed good correlation with GHb, could be measured on several drops of blood dried on filter paper treated with glucose oxidase. Filter papers are posted to the laboratory prior to clinic visits, and by having the DBG result available more rational diabetic management is possible. For DBG, the intra- and inter-assay coefficient of variation at three levels is less than 6%. Reference values in non-diabetic children have been calculated and are compared with values obtained in ‘good’ clinical diabetic control and in ‘fair’ control. The filter-paper assay DBG method has a high degree of patient acceptance.

Comparative Study of the Solid-Matrix Luminescence Properties of Perdeuterated Phenanthrene and Phenanthrene Adsorbed on Several Solid Matrices

1996 ◽  
Vol 50 (9) ◽  
pp. 1140-1144 ◽  
Author(s):  
Savakkattupalayam M. Ramasamy ◽  
Robert J. Hurtubise
Keyword(s):  
Rate Constants ◽  
Singlet State ◽  
Luminescence Properties ◽  
Solid Matrix ◽  
Deuterium Isotope Effect ◽  
Excited Singlet ◽  
Excited Triplet ◽  
Wide Range ◽  
Solid Matrices ◽  
Effects Of Temperature

Temperature was varied over a wide range to determine its effect on the luminescence properties of deuterated phenanthrene and phenanthrene adsorbed on a number of solid matrices. Not only were insights into the effects of temperature and solid matrices on the luminescence properties acquired but also the deuterium isotope effect revealed unique information about the role played by the solid matrix in the luminescence of the model compounds. In addition, comparisons of nonradiative rate constants and the efficiencies of intersystem crossing revealed important differences among the solid matrices in altering these parameters. The perdeuterated phenanthrene and phenanthrene proved to be useful probes for investigating the effects of solid matrices on the excited triplet state of phosphors because the excited singlet state of the lumiphor was affected very little by the solid matrices, and the rate constants of phosphorescence for the two phosphors are essentially the same.

Sweating rate and the electrolyte content of skin secretions of Bos taurus and Bos indicus cross-bred cows

1970 ◽  
Vol 75 (3) ◽  
pp. 397-402 ◽  
Author(s):  
K. G. Johnson
Keyword(s):  
Filter Paper ◽  
Bos Taurus ◽  
Bos Indicus ◽  
Lumbar Region ◽  
Sweating Rate ◽  
Ambient Temperatures ◽  
Electrolyte Content ◽  
Air Temperatures ◽  
Filter Papers ◽  
Sodium And Potassium

SUMMARYSweating rate and the electrolyte content of secretions from the skin of cattle have been measured on five Bos taurus and five B. indicus cross-bred cows by absorbing secretions into filter papers under polythene disks applied to shaved skin areas on the shoulder, sacral and lumbar regions for 5 min. The increase in weight of the filter paper was taken as a measure of sweating rate and the distilled water eluate from the filter paper was analysed for sodium and potassium. Animals were exposed for 4 h to air temperatures of 20–45 °C at 30% r.h., and for 5–7 h to air temperatures of 40 and 45 °C at 40% r.h. Estimated sweating rates were low by comparison with previously reported values, probably due to rising levels of humidity under the polythene disks during exposure to the skin. B. indicus cross-bred cows had higher sweating rates than B. taurus cows at high air temperatures but the difference between the groups was not significant statistically. Sweating rates were generally highest on the shoulder and lowest on the lumbar region.The amounts of sodium and potassium recovered from filter papers were small and very variable at low air temperatures but increased significantly with air temperature (P < 0·01). No significant differences in the amounts of electrolyte recovered from filter papers were recorded between the species groups or between different sites of collection. The secretions from cattle skin at high ambient temperatures contained at least four to five times as much potassium as sodium. Total sodium and potassium loss through the skin of these experimental animals at the highest ambient temperatures was estimated to be no more than 1–3 % of the sodium and potassium intake in the feed. Absorbing sweat on to filter paper as a method of measuring sweating rate and sweat composition is rather less satisfactory for use with cattle than with man.

scholarly journals The viscosity of dilute solutions of strong electrolytes

1931 ◽  
Vol 134 (824) ◽  
pp. 413-427 ◽  
Keyword(s):  
Empirical Equation ◽  
Relative Viscosity ◽  
Theoretical Treatment ◽  
High Dilution ◽  
Equivalent Concentration ◽  
Pure Solvent ◽  
Wide Range ◽  
Strong Electrolytes ◽  
Negative Viscosity ◽  
Stiffening Effect

Until very recently, no empirical equation had been found to represent satisfactorily the variation with concentration of the relative viscosity of electrolytes, nor had any adequate theoretical treatment of the problem been put forward. In 1929, however, Jones and Dole showed that the fluidity (or reciprocal of the relative viscosity) of a salt solution could be represented over a fairly wide range of concentration by an equation of the form ϕ = 1 + A√ c +B c , where ϕ is the fluidity, c the equivalent concentration, and A and B are empirical constants. The value of B is negative in the case of salts which increase the viscosity of water, and positive in cases of so-called “negative viscosity,” where the viscosity of the solution is less than that of the pure solvent. Jones and Dole argued further that the stiffening effect of the interionic forces would tend to make the constant A, which determines the viscosity at high dilution, always negative. A little later, Falkenhagen and Dole treated the problem theoretically from the standpoint of the ion-atmosphere theory of Debye and Huckel. They confirmed the suggestion that at high dilution the electrolyte must always increase the viscosity of the solvent, and showed that the relative viscosity of an electrolyte solution at high dilution must be represented by an equation of the form η μ / η 0 = 1 + K √ μ , where η μ is the viscosity of the solution, η 0 is the viscosity of the solvent, μ is the equivalent concentration, K is a constant.

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