Reducing capacities in continuously released low molecular weight fractions from bulk humic acids

2019 ◽  
Vol 244 ◽  
pp. 172-179 ◽  
Author(s):  
Jun Cao ◽  
Jie Jiang
Fuel ◽  
1981 ◽  
Vol 60 (8) ◽  
pp. 685-688 ◽  
Author(s):  
Elena M. Balabanova-Radonova ◽  
Maia D. Stefanova

2019 ◽  
Vol 25 (11) ◽  
pp. 1187-1199 ◽  
Author(s):  
Soukaina Bouissil ◽  
Guillaume Pierre ◽  
Zainab El Alaoui-Talibi ◽  
Philippe Michaud ◽  
C. El Modafar ◽  
...  

Background: Recently, researchers have given more and more consideration to natural polysaccharides thanks to their huge properties such as stability, biodegradability and biocompatibility for food and therapeutics applications. Methods: a number of enzymatic and chemical processes were performed to generate bioactive molecules, such as low molecular weight fractions and oligosaccharides derivatives from algal polysaccharides. Results: These considerable characteristics allow algal polysaccharides and their derivatives such as low molecular weight polymers and oligosaccharides structures to have great potential to be used in lots of domains, such as pharmaceutics and agriculture etc. Conclusion: The present review describes the mains polysaccharides structures from Algae and focuses on the currents agricultural (fertilizer, bio-elicitor, stimulators, signaling molecules and activators) and pharmaceutical (wound dressing, tissues engineering and drugs delivery) applications by using polysaccharides and/or their oligosaccharides derivatives obtained by chemical, physical and enzymatic processes.


1970 ◽  
Vol 43 (6) ◽  
pp. 1439-1450 ◽  
Author(s):  
W. V. Smith ◽  
S. Thiruvengada

Abstract A preparative fractionation of about 23 g of a commercial cis-polybutadiene rubber is described. The method employed was a solvent elution chromatographic method with very little temperature gradient. The molecular weight distributions of the fractions obtained were determined by an analytical fractionation of 20 mg of polymer. The method was similar to the preparative fractionation and involved solvent elution chromatography. The fractions obtained were assayed for quantity, molecular weight, and molecular weight distribution by GPC. The low molecular weight fractions of the preparative fractionation had molecular weight distributions which could be closely approximated by two log normal distributions, the low molecular weight component having the narrower width. The ratio of weight to number average molecular weight was found to be about 1.1 for these samples. The higher molecular weight fractions could also be approximated by two log normal distributions; however, in these fractions the low molecular weight component had a very broad distribution but constituted only a small portion of the sample. The widths of the GPC curves of the fractions correlate satisfactorily with the molecular weight distributions found by the analytical refractionations. The GPC width is a sensitive criterion of the width of the molecular weight distribution even when only two columns are used. It is felt that the analytical fractionation procedure presented gives more detailed information on the molecular weight distribution than is easily obtainable from an ordinary GPC curve.


1982 ◽  
Vol 39 (12) ◽  
pp. 1596-1601 ◽  
Author(s):  
M. Roch ◽  
J. A. McCarter ◽  
A. T. Matheson ◽  
M. J. R. Clark ◽  
R. W. Olafson

Hepatic metallothionein was measured in livers of freshly killed rainbow trout (Salmo gairdneri) using differential pulse polarography. The fish were caught in metal-contaminated lakes of the Campbell River watershed and in a nearby control lake. The livers were analyzed for zinc, copper, and cadmium using atomic absorption spectrophotometry. High and low molecular weight protein fractions were separated by gel chromatography from liver cytosols and analyzed for metals. A downward trend from the most contaminated lake to the least was found in levels of zinc in the water, of cadmium and copper in high molecular weight fractions, and of copper in low molecular weight fractions and metallothionein. The concentration of metallothionein is a useful quantitative measure of the degree of exposure of fish to heavy metals.Key words: metallothionein, rainbow trout, Salmo gairdneri; heavy metal pollution, sublethal exposures, mine wastes


1985 ◽  
Vol 339 (2) ◽  
pp. 237-244 ◽  
Author(s):  
A. Bateman ◽  
P. Boden ◽  
A. Dell ◽  
I.R. Duce ◽  
D.L.J. Quicke ◽  
...  

2013 ◽  
Vol 4 (12) ◽  
pp. 1835 ◽  
Author(s):  
Seiichi Munesue ◽  
Yasuhiko Yamamoto ◽  
Ryouta Urushihara ◽  
Kouhei Inomata ◽  
Hidehito Saito ◽  
...  

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