The Solidified Inert Gases as Model Substances

1958 ◽  
Vol 16 (3_6) ◽  
pp. 267-276 ◽  
Author(s):  
G. O. Jones
Keyword(s):  
Inert Gases ◽  
Model Substances

MEASUREMENT OF BLOOD FLOW WITH FREELY DIFFUSIBLE INDICATORS AS INERT GASES, ANTIPYRINE, LABELLED WATER AND RUBIDIUM

1972 ◽  
Vol 68 (2_Supplb) ◽  
pp. S95-S111 ◽  
Author(s):  
Niels A. Lassen ◽  
Ole Andrée Larsen
Keyword(s):  
Blood Flow ◽  
Flow Measurement ◽  
Capillary Wall ◽  
Inert Gases ◽  
Tissue Blood Flow ◽  
Blood Flow Measurement

ABSTRACT Indicators which freely cross the capillary wall can be used for measurement of tissue blood flow in many different ways. Basically one can distinguish two categories of methods, viz. the ones where the indicator enters the tissue via the inflowing blood and the ones where the indicator is deposited locally in the tissue. The most important methods are briefly described with special emphasis on the theory of blood flow measurement.

Interaction of Ba Atoms and Ba(+) Ions with Inert Gases

1991 ◽  
Author(s):  
Keith D. Bonin ◽  
Will Happer
Keyword(s):  
Inert Gases

A simple test for monitoring biodegradable industrial pollution in a receiving stream

1999 ◽  
Vol 39 (10-11) ◽  
pp. 221-224 ◽  
Author(s):  
Jana Zagorc-Končan ◽  
J. Šömen
Keyword(s):  
Hazard Assessment ◽  
Industrial Pollution ◽  
Self Regulation ◽  
Oxygen Demand ◽  
Organic Pollution ◽  
Organic Substances ◽  
Simple Test ◽  
Industrial Pollutants ◽  
Model Substances ◽  
Receiving Stream

Microbial purification capacity is an important factor in natural self-regulation in water. Evaluating the fate of biodegradable organic pollution downstream from the discharge seems an appropriate way to follow the effect of pollution and its hazard assessment, which dictates the needed sanitation measures. We suggest a simple test for such monitoring. A modification of the additional oxygen demand test, standardised in Ausgewählte Methoden der Wasseruntersuchung, was applied in two river case studies. The additional oxygen demand is a measure of the capability and rate of biodegradation of known organic substance as well as of the amount and activity of heterotrophic organisms in the river. The original test using peptone and glucose as additional feedings of BOD samples was modified by the use of other organic biodegradable model substances characteristic for individual industrial pollutants. The test was found to be an excellent indicator of adapted microorganisms, which are essential for the biodegradation of the appointed organic substances downstream of their discharge into the receiving stream.

Benzyl ethers of methyl α-D-glucopyranoside

1980 ◽  
Vol 45 (7) ◽  
pp. 1959-1963 ◽  
Author(s):  
Dušan Joniak ◽  
Božena Košíková ◽  
Ludmila Kosáková
Keyword(s):  
Kinetic Study ◽  
Spectrophotometric Determination ◽  
Reductive Cleavage ◽  
Ether Bond ◽  
Benzyl Ethers ◽  
Acid Catalyzed ◽  
Model Substances ◽  
Hydrolysis Of

Methyl 4-O-(3-methoxy-4-hydroxybenzyl) and methyl 4-O-(3,5-dimethoxy-4-hydroxybenzyl)-α-D-glucopyranoside and their 6-O-isomers were prepared as model substances for the ether lignin-saccharide bond by reductive cleavage of corresponding 4,6-O-benzylidene derivatives. Kinetic study of acid-catalyzed hydrolysis of the compounds prepared was carried out by spectrophotometric determination of the benzyl alcoholic groups set free, after their reaction with quinonemonochloroimide, and it showed the low stability of the p-hydroxybenzyl ether bond.

scholarly journals Polyelectrolyte Functionalisation of Track Etched Membranes: Towards Charge-Tuneable Adsorber Materials

Membranes ◽  
2021 ◽  
Vol 11 (7) ◽  
pp. 509
Author(s):  
Lisa Wiedenhöft ◽  
Mohamed M. A. Elleithy ◽  
Mathias Ulbricht ◽  
Felix H. Schacher
Keyword(s):  
Methylene Blue ◽  
Heavy Metal Ions ◽  
Glycolic Acid ◽  
Organic Dyes ◽  
Langmuir Model ◽  
Surface Grafting ◽  
Hydraulic Permeability ◽  
Cylindrical Pores ◽  
Model Substances ◽  
External Stimuli

Porous adsorber membranes are promising materials for the removal of charged pollutants, such as heavy metal ions or organic dyes as model substances for pharmaceuticals from water. Here, we present the surface grafting of polyethylene terephthalate (PET) track-etched membranes having well defined cylindrical pores of 0.2 or 1 µm diameter with two polyelectrolytes, poly(2-acrylamido glycolic acid) (PAGA) and poly(N-acetyl dehydroalanine) (PNADha). The polyelectrolyte functionalised membranes were characterised by changes in wettability and hydraulic permeability in response to the external stimuli pH and the presence of Cu2+ ions. The response of the membranes proved to be consistent with functionalisation inside the pores, and the change of grafted polyelectrolyte macro-conformation was due to the reversible protonation or binding of Cu2+ ions. Moreover, the adsorption of the model dye methylene blue was studied and quantified. PAGA-grafted membranes showed an adsorption behavior following the Langmuir model for methylene blue.

Crystal Violet, an Electronic Model Substance for Rubber and Related Olefins

1951 ◽  
Vol 24 (1) ◽  
pp. 169-181 ◽  
Author(s):  
G. J. van Veersen
Keyword(s):  
Crystal Violet ◽  
Electronic Structures ◽  
Radical Reaction ◽  
Test Tube ◽  
Chemical Agent ◽  
Blue Color ◽  
Electronic Model ◽  
Model Substance ◽  
Model Substances ◽  
Polar Reaction

Abstract It is shown that triphenylmethyl dyes like crystal violet can be used as model substances for rubber and related olefins. Arguments are given in support of the assumption that agents which react with rubber and related olefins in a polar manner cause a reversible shift in color from blue to yellow with crystal violet, whereas a fading of the blue color of crystal violet (if alkaline or reducing agents are excluded) points to a radical reaction. Since the electronic structures of donor olefins and crystal violet are considered and not the molecular structure, as usually is done in the choice of a model substance, these dyes have been named electronic model substances. Though crystal violet, as an electronic model substance cannot be used for the study of the overall reactions, information can often be obtained concerning the first step in a reaction of rubber with a certain chemical agent by means of a simple test-tube reaction with crystal violet. It was pointed out that the π-electron availability at the non-methylated carbon atom of the double bond in rubber and at the nitrogen atoms in crystal violet is probably of the same order. As an application of crystal violet as an electronic model substance for rubber, a polar reaction between sulfur and rubber is suggested as the first step in vulcanization.

Pepsin inactivation by inert gases

1952 ◽  
Vol 254 (4) ◽  
pp. 344
Author(s):  
George M. Naimark ◽  
William A. Mosher
Keyword(s):  
Inert Gases

Effects of hydrostatic pressure and inert gases on platelet aggregation in vitro

1990 ◽  
Vol 69 (6) ◽  
pp. 2239-2247 ◽  
Author(s):  
D. M. Pickles ◽  
D. Ogston ◽  
A. G. Macdonald
Keyword(s):  
Platelet Aggregation ◽  
Hydrostatic Pressure ◽  
Maximum Degree ◽  
Platelet Rich Plasma ◽  
Control Level ◽  
Inert Gases ◽  
Partial Pressures ◽  
Compression Cycle ◽  
Anesthetic Potency

A novel cuvette was used to subject citrated platelet-rich plasma (PRP) to high hydrostatic pressure with negligible contamination by He (used for compression of the apparatus). Aggregation was induced at pressure by ADP and quantified turbidimetrically. The maximum degree of aggregation (MDA) was reduced from a control level of 82.2 to 53.6% by exposure to 101 ATA. Because decompression bubbles did not form, aggregation was also measured immediately after a compression cycle. After exposure to 101 ATA hydrostatic pressure, platelets responded normally to ADP at 1 ATA. In a matching apparatus, PRP was equilibrated with high partial pressures of inert gases. Normal physiological plasma Po2 and pH were maintained during equilibration. N2O (5 ATA) reduced the MDA from 86.5 (control) to 58.1%. N2 (51 ATA) reduced the MDA from 74.7 (control) to 51.6%, and 101 ATA Pn2 reduced the MDA from 78.0 (control) to 32.3%. He (100 ATA) reduced the MDA from 83.6 to 38.6%. It was concluded that platelet aggregation was relatively sensitive to hydrostatic pressure and less sensitive to inert gases than predicted from their anesthetic potency ratios.

Analytical method for inert gases in alloy powders

1990 ◽  
Vol 124 (1) ◽  
pp. 15-19 ◽  
Author(s):  
G.R. Smolik ◽  
J.E. Delmore
Keyword(s):  
Analytical Method ◽  
Inert Gases
Sign in / Sign up

Export Citation Format

Share Document