Water masses and distribution of physico-chemical properties in the Western Bransfield Strait and Gerlache Strait during Austral summer 1995/96

A remarkable shift in the species composition and size distribution of the phytoplankton community have been observed in coastal waters along the Antarctic Peninsula over the last three decades. Smaller photoautotrophs such as cryptophytes are becoming more abundant and important for the regional ecosystems. In this study, flow cytometry was used to quantify the smallest phytoplankton in the central Bransfield Strait and explore their distribution across the strait in relation to physical and chemical properties of the two major water masses: the warmer and less saline Transitional Zonal Water with Bellingshausen Sea influence (TBW), and the cold and salty Transitional Zonal Water with Weddell Sea influence (TWW). Pico- and nano-phytoplankton clusters were distinguished and enumerated in the cytograms: photosynthetic picoeukaryotes, cryptophytes (about 9 µm in size), and smaller (3 µm) nanophytoplankton. It was shown that nanophytoplankton developed higher abundances and biomasses in the warmer and less saline TBW. This biotope was characterized by a more diverse community with a pronounced dominance of Cryptophyta in terms of biomass. The results support the hypothesis that increasing melt-water input can potentially support spatial and temporal extent of cryptophytes. The replacement of large diatoms with small cryptophytes leads to a significant shift in trophic processes in favor of the consumers such as salps, which able to graze on smaller prey.

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Studies on the Effects of Pollution on the Diaton Communities of the St Lawrence River Near

Water Quality Research Journal ◽

10.2166/wqrj.1974.014 ◽

1974 ◽

Vol 9 (1) ◽

pp. 135-141 ◽

Cited By ~ 2

Author(s):

Alauddin Ahmad ◽

Andrzej Chodorowski ◽

Pierre Legendre

Keyword(s):

Chemical Properties ◽

Water Masses ◽

Artificial Substrates ◽

Total Hardness ◽

Cladophora Glomerata ◽

Algal Communities ◽

Ottawa River ◽

Glass Slides ◽

Physico Chemical ◽

St Lawrence River

Abstract A study was conducted to establish the physico-chemical and biological characteristics of two water masses (St. Lawrence and Ottawa) just before they meet near Montreal. The two water masses show marked differences in physico-chemical properties and in the composition of algal communities they support. As compared with that of St. Lawrence River, the water of Ottawa River shows lower values of alkalinity, conductivity, total hardness and chlorides. The value of pH is also slightly lower. But the quantity of Silica and Ammonia present in the Ottawa River is much higher. There is a marked difference in the composition of Algal communities supported by the two water masses. Over 100 species of Diatoms were found to colonize the artificial substrates (glass slides), of which only about 40 species were found to be common in both waters. Some 38 species were found only in St. Lawrence River and another 39 species only in Ottawa River. The two water masses also differed in supporting other groups of algae. Cladophora glomerata was very abundant in Ottawa River, whereas, it was absent or very rare in St. Lawrence River. On the other hand, some members of Zygnemaceae (like Sirogonium sticticum, Spirogyra sp., Mougeotia sp., and Zygnema sp.) were very abundant in St. Lawrence River and very rare in Ottawa River.

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Decoration of specific sites on freeze-fractured membranes

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100081565 ◽

1978 ◽

Vol 36 (2) ◽

pp. 140-141

Author(s):

H. Gross ◽

H. Moor

Keyword(s):

Pure Water ◽

Freeze Fracture ◽

Chemical Properties ◽

Surface Forces ◽

Sulfate Pentahydrate ◽

Copper Sulfate Pentahydrate ◽

Physico Chemical ◽

Water Of Hydration ◽

Small Container ◽

Binding Forces

Fracturing under ultrahigh vacuum (UHV, p ≤ 10-9 Torr) produces membrane fracture faces devoid of contamination. Such clean surfaces are a prerequisite foe studies of interactions between condensing molecules is possible and surface forces are unequally distributed, the condensate will accumulate at places with high binding forces; crystallites will arise which may be useful a probes for surface sites with specific physico-chemical properties. Specific “decoration” with crystallites can be achieved nby exposing membrane fracture faces to water vopour. A device was developed which enables the production of pure water vapour and the controlled variation of its partial pressure in an UHV freeze-fracture apparatus (Fig.1a). Under vaccum (≤ 10-3 Torr), small container filled with copper-sulfate-pentahydrate is heated with a heating coil, with the temperature controlled by means of a thermocouple. The water of hydration thereby released enters a storage vessel.

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PHYSICO CHEMICAL PROPERTIES OF NICKEL OXIDE AT HIGH TEMPERATURE

Le Journal de Physique Colloques ◽

10.1051/jphyscol:1976798 ◽

1976 ◽

Vol 37 (C7) ◽

pp. C7-438-C7-442 ◽

Cited By ~ 2

Author(s):

R. FARHI ◽

G. PETOT-ERVAS

Keyword(s):

High Temperature ◽

Nickel Oxide ◽

Chemical Properties ◽

Physico Chemical

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Physico-Chemical Properties of Recombinant Desulphatohirudin

Thrombosis and Haemostasis ◽

10.1055/s-0038-1645073 ◽

1990 ◽

Vol 63 (03) ◽

pp. 499-504 ◽

Cited By ~ 4

Author(s):

A Electricwala ◽

L Irons ◽

R Wait ◽

R J G Carr ◽

R J Ling ◽

...

Keyword(s):

Molecular Weight ◽

Gel Filtration ◽

Chemical Properties ◽

Alpha Helix ◽

Apparent Molecular Weight ◽

Correlation Spectroscopy ◽

Nmr Studies ◽

Recombinant Hirudin ◽

Physico Chemical ◽

Recombinant Molecule

SummaryPhysico-chemical properties of recombinant desulphatohirudin expressed in yeast (CIBA GEIGY code No. CGP 39393) were reinvestigated. As previously reported for natural hirudin, the recombinant molecule exhibited abnormal behaviour by gel filtration with an apparent molecular weight greater than that based on the primary structure. However, molecular weight estimation by SDS gel electrophoresis, FAB-mass spectrometry and Photon Correlation Spectroscopy were in agreement with the theoretical molecular weight, with little suggestion of dimer or aggregate formation. Circular dichroism studies of the recombinant molecule show similar spectra at different pH values but are markedly different from that reported by Konno et al. (13) for a natural hirudin-variant. Our CD studies indicate the presence of about 60% beta sheet and the absence of alpha helix in the secondary structure of recombinant hirudin, in agreement with the conformation determined by NMR studies (17)

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Physico-chemical properties of the rare-earth metals, scandium, and yttrium

Uspekhi Fizicheskih Nauk ◽

10.3367/ufnr.0079.196302c.0263 ◽

1963 ◽

Vol 79 (2) ◽

pp. 263-293 ◽

Cited By ~ 10

Author(s):

E.M. Savitskii ◽

V.F. Terekhova ◽

O.P. Naumkin

Keyword(s):

Rare Earth ◽

Rare Earth Metals ◽

Chemical Properties ◽

Physico Chemical ◽

The Rare Earth

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Physico chemical properties and gas adsorption separation characteristics of Itaya zeolite and its modified products.

Journal of the Society of Materials Science Japan ◽

10.2472/jsms.39.996 ◽

1990 ◽

Vol 39 (442) ◽

pp. 996-1000 ◽

Cited By ~ 2

Author(s):

Ayao TAKASAKA ◽

Hideyuki NEMOTO ◽

Hirohiko KONO ◽

Yoshihiro MATSUDA

Keyword(s):

Gas Adsorption ◽

Chemical Properties ◽

Physico Chemical

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Development of Ketchup from Sudanese Red karkade (Hibiscus sabdariffa L.) byproduct

Food Biology ◽

10.25081/fb.2018.v7.3664 ◽

1970 ◽

pp. 19-23

Author(s):

Nawal Abdel-Gayoum Abdel-Rahman

Keyword(s):

Sensory Quality ◽

Chemical Properties ◽

Storage Period ◽

Gum Arabic ◽

Raw Material ◽

Soluble Solids ◽

Hibiscus Sabdariffa ◽

Overall Acceptability ◽

Physico Chemical ◽

Tomato Ketchup

The aim of this study is to use of karkede (Hibiscus sabdariffa L.) byproduct as raw material to make ketchup instead of tomato. Ketchup is making of various pulps, but the best type made from tomatoes. Roselle having adequate amounts of macro and micro elements, and it is rich in source of anthocyanine. The ketchup made from pulped of waste of soaked karkede, and homogenized with starch, salt, sugar, ginger (Zingiber officinale), kusbara (Coriandrum sativum) and gum Arabic. Then processed and filled in glass bottles and stored at two different temperatures, ambient and refrigeration. The total solids, total soluble solids, pH, ash, total titratable acidity and vitamin C of ketchup were determined. As well as, total sugars, reducing sugars, colour density, and sodium chloride percentage were evaluated. The sensory quality of developed product was determined immediately and after processing, which included colour, taste, odour, consistency and overall acceptability. The suitability during storage included microbial growth, physico-chemical properties and sensory quality. The karkede ketchup was found free of contaminants throughout storage period at both storage temperatures. Physico-chemical properties were found to be significantly differences at p?0.05 level during storage. There were no differences between karkade ketchup and market tomato ketchup concerning odour, taste, odour, consistency and overall acceptability. These results are encouraging for use of roselle cycle as a raw material to make acceptable karkade ketchup.

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