Mechanism of nucleophilic substitution in chromium(III) complexes. II. Formation of Acetatopentamminechromium(III)-ion from aquopentamminechromium(III)-ion in acetic acid ? sodium acetate buffer media

The hydrogen ion reversal points of human, dog, and cat serous membranes have been determined with acetic acid-sodium acetate buffer mixtures, and are compared with the reversal points of the same membranes estimated with citrate-phosphate mixtures. The values with acetate buffer are about one-quarter of a pH unit higher (more alkaline) for fat membranes and almost one-half a pH unit higher for lean membranes. The acetate values are believed to correspond more closely to the true hydrogen ion reversal points. The reversal points are again found to be characteristic for membrane and species. No evidence of a postmortem shift in reversal point has been found. The charge of the membranes even in the living animal is capable of ready and repeated reversal.

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Viscosity Properties of Chitosan Solutions in Acetic Acid and Sodium Acetate Buffer

Izvestiya of Saratov University New Series Series Chemistry Biology Ecology ◽

10.18500/1816-9775-2014-14-2-5-9 ◽

2014 ◽

Vol 14 (2) ◽

pp. 5-9

Author(s):

Ekaterina Vladimirovna Kolsanova ◽

◽

Emil Esenbekovich Orozaliev ◽

Anna Borisovna Shipovskaya ◽

◽

...

Keyword(s):

Acetic Acid ◽

Sodium Acetate ◽

Acetate Buffer ◽

Sodium Acetate Buffer

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The role of silicon in forages: A quantitative X-Ray study

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100126871 ◽

1987 ◽

Vol 45 ◽

pp. 416-417

Author(s):

Janet H. Woodward ◽

D. E. Akin

Keyword(s):

Sodium Acetate ◽

Dry Matter ◽

Acetate Buffer ◽

Plant Tissues ◽

Sodium Acetate Buffer ◽

X Ray ◽

Dry Matter Digestibility ◽

Percent Composition

Silicon (Si) is distributed throughout plant tissues, but its role in forages has not been clarified. Although Si has been suggested as an antiquality factor which limits the digestibility of structural carbohydrates, other research indicates that its presence in plants does not affect digestibility. We employed x-ray microanalysis to evaluate Si as an antiquality factor at specific sites of two cultivars of bermuda grass (Cynodon dactvlon (L.) Pers.). “Coastal” and “Tifton-78” were chosen for this study because previous work in our lab has shown that, although these two grasses are similar ultrastructurally, they differ in in vitro dry matter digestibility and in percent composition of Si.Two millimeter leaf sections of Tifton-7 8 (Tift-7 8) and Coastal (CBG) were incubated for 72 hr in 2.5% (w/v) cellulase in 0.05 M sodium acetate buffer, pH 5.0. For controls, sections were incubated in the sodium acetate buffer or were not treated.

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STARCH GEL ELECTROPHORESIS OF COBRA AND RATTLESNAKE VENOMS

Canadian Journal of Biochemistry and Physiology ◽

10.1139/o63-120 ◽

1963 ◽

Vol 41 (4) ◽

pp. 1073-1078 ◽

Cited By ~ 21

Author(s):

J. M. Neelin

Keyword(s):

Ionic Strength ◽

Gel Electrophoresis ◽

Sodium Acetate ◽

Acetate Buffer ◽

Starch Gel Electrophoresis ◽

Two Dimensional ◽

Sodium Acetate Buffer ◽

Cacodylate Buffer ◽

Starch Gel ◽

Acidic Proteins

The effect of pH on gradient starch gel electrophoresis of the venoms of Crotalus adamanteus and Naja flava has been examined. Sodium acetate buffer, pH 4.1, ionic strength 0.020, appeared most effective for resolution of the former venom, and acetate buffer, pH 4.7, or cacodylate buffer, pH 6.0, for the latter. Two-dimensional starch gel electrophoresis resolved at least 20 zones from the crotaline venom and 11 from the colubrid. Two zones of hemolytic activity were separated from each venom: in C. adamanteus the less cationic zone included possibly two or more acidic proteins; the corresponding zone of N. flava was more basic, more homogeneous, and more active under the conditions of assay.

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XRD Identification of Ore Minerals during Cruises: Refinement of Extraction Procedure with Sodium Acetate Buffer

Minerals ◽

10.3390/min10020160 ◽

2020 ◽

Vol 10 (2) ◽

pp. 160

Author(s):

Jelena Milinovic ◽

Ágata Alveirinho Dias ◽

Ana I. Janeiro ◽

Manuel F. C. Pereira ◽

Sofia Martins ◽

...

Keyword(s):

Sodium Acetate ◽

Extraction Procedure ◽

Xrd Analysis ◽

Acetate Buffer ◽

Sodium Acetate Buffer ◽

Sediment Samples ◽

New Information ◽

Ore Minerals ◽

Mid Atlantic Ridge ◽

Seafloor Sediments

The on-board identification of ore minerals during a cruise is often postponed until long after the cruise is over. During the M127 cruise, 21 cores with deep-seafloor sediments were recovered in the Trans-Atlantic Geotraverse (TAG) field along the Mid Atlantic Ridge (MAR). Sediments were analyzed on-board for physicochemical properties such as lightness (L*), pH and Eh. Selected samples were studied for mineral composition by X-ray powder diffraction (XRD). Based on XRD data, sediment samples were separated into high-, low- and non-carbonated. Removal of carbonates is a common technique in mineralogical studies in which HCl is used as the extraction agent. In the present study, sequential extraction was performed with sodium acetate buffer (pH 5.0) to remove carbonates. The ratio between the highest calcite XRD reflection in the original samples (Iorig) vs its XRD-reflection in samples after their treatment with the buffer (Itreat) was used as a quantitative parameter of calcite removal, as well as to identify minor minerals in carbonated samples (when Iorig/Itreat > 24). It was found that the lightness parameter (L*) showed a positive correlation with calcite XRD reflection in selected TAG samples, and this could be applied to the preliminary on-board determination of extraction steps with acetate buffer (pH 5.0) in carbonated sediment samples. The most abundant minerals detected in carbonated samples were quartz and Al- and Fe-rich clays. Other silicates were also detected (e.g., calcic plagioclase, montmorillonite, nontronite). In non-carbonated samples, Fe oxides and hydroxides (goethite and hematite, respectively) were detected. Pyrite was the dominant hydrothermal mineral and Cu sulfides (chalcopyrite, covellite) and hydrothermal Mn oxides (birnessite and todorokite) were mineral phases identified in few samples, whereas paratacamite was detected in the top 20 cm of the core. The present study demonstrates that portable XRD analysis makes it possible to characterize mineralogy at cored sites, in particular in both low- and high-carbonated samples, before the end of most cruises, thus enabling the quick modification of exploration strategies in light of new information as it becomes available in near-real time.

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The recombination of dimers of immunoglobulin peptide chains

Biochemical Journal ◽

10.1042/bj1180703 ◽

1970 ◽

Vol 118 (5) ◽

pp. 703-712 ◽

Cited By ~ 91

Author(s):

G. T. Stevenson ◽

K. J. Dorrington

Keyword(s):

Immunoglobulin G ◽

Sodium Acetate ◽

Optical Rotatory Dispersion ◽

Acetate Buffer ◽

Light Chains ◽

Sodium Acetate Buffer ◽

Covalent Bonds ◽

Myeloma Protein ◽

Disulphide Bonds ◽

Antigenic Properties

1. Both the γ and light peptide chains of human pooled and myeloma immunoglobulin G can be prepared as non-aggregating dimers at pH5.4 in 4mm-sodium acetate buffer. The dimeric state is maintained by non-covalent bonds, since the formation of interchain disulphide bonds was prevented by alkylation of the thiol groups. In the case of the light chains there is some evidence that the dimers are in equilibrium with a small amount of monomer. 2. When such dimers of the γ and light chains are mixed at pH5.4 in 4mm-sodium acetate buffer they combine rapidly, yielding a product that resembles the original immunoglobulin G in its physicochemical and antigenic properties. However, the original optical rotatory dispersion spectrum was regained only with the homogeneous myeloma protein. The recombined pooled immunoglobulin G had a spectrum slightly different from the original, suggesting that at least some of the recombinant molecules had not regained native conformations. 3. Dimers of γ chains stabilized by interchain disulphide bonds were able to recombine with light chains. However, light chains stabilized in the dimeric state by interchain disulphide bonds would not combine with γ chains. 4. The chains of rabbit immunoglobulin G behave similarly to the human chains in this system, apart from the alkylated light chains showing clearer evidence of monomeric components.

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