Thermokinetic analysis of the stability of acetic anhydride hydrolysis in isothermal calorimetry techniques

Abstract The determination of chlorophenols (CPs) in water samples is a subject of increasing interest. Reduction of sample storage space and the stability of CPs when present at very low levels are still problems that deserve research. The stability of CPs at ng/L levels at different temperatures and in the presence or absence of sodium carbonateand acetic anhydride was studied for up to 39 days. Stable and reproducible CP concentrations for about a month of storage in both river and wastewater were achieved in two storage conditions as follows: at –18°C with addition of 10% sodium chloride; and at 4°C with addition of both 10% sodium chloride and 10 mg/mL sodium carbonate. These sample treatments are good alternatives to the immobilization of CPs on SPE cartridges in terms of both analyte stability and saving of storage space.

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The potential role of isothermal calorimetry in studies of the stability of fresh-cut fruits

LWT ◽

10.1016/j.lwt.2012.07.020 ◽

2012 ◽

Vol 49 (2) ◽

pp. 320-323 ◽

Cited By ~ 14

Author(s):

P. Rocculi ◽

V. Panarese ◽

U. Tylewicz ◽

P. Santagapita ◽

E. Cocci ◽

...

Keyword(s):

Potential Role ◽

Isothermal Calorimetry ◽

Fresh Cut ◽

The Stability

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Optimizing buffer conditions to improve crystallizability and SAXS measurement

Acta Crystallographica Section A Foundations and Advances ◽

10.1107/s2053273314088573 ◽

2014 ◽

Vol 70 (a1) ◽

pp. C1142-C1142

Author(s):

Stephane Boivin ◽

Sandra Kozak ◽

Vanessa Vieira ◽

Gry Rasmussen ◽

Rob Meijers

Keyword(s):

Sample Preparation ◽

High Throughput ◽

Isothermal Calorimetry ◽

Research Area ◽

The European Union ◽

Local Staff ◽

Saxs Measurement ◽

High Throughput Method ◽

Sample Characterization ◽

The Stability

The Sample Preparation and Characterization (SPC) facility at EMBL Hamburg is situated next to the PETRA3 beamlines for protein crystallography and small angle scattering (SAXS) that are operated by EMBL. The facility is equipped with molecular biology and biophysical instrumentation to carry out purification and characterization of macromolecular samples. It serves a mixed community of local EMBL scientists, beamline visitors and scientists from the European Union research area. Most incoming samples are destined for high-throughput crystallization at the facility or characterization by SAXS. The facility offers standardized quality control reports on each incoming sample, including characterization by mass spectrometry and Thermofluor. Based on this report, local staff can suggest and perform optimization protocols that increase the stability of the sample. For instance, Thermofluor screens(1) were developed that probe the effect of buffers and additives that are commonly used in sample preparation. These systematic screens provide a high-throughput method to identify stabilizing conditions for sample purification, storage and structural characterization. This technique has been also a valuable asset providing a high-throughput method for assessing the crystallizability of proteins by screening for conditions which contribute to the protein sample homogeneity, stability and solubility. The home-made screens have been tested on more than 200 different protein constructs at SPC facility. The aim of the SPC facility is to integrate off-line biophysical techniques with synchrotron beamlines, to offer the European user community a full package for sample characterization. The facility is especially geared towards cell biologists with little experience in structure determination. Expert staff is available to help to plan, perform and interpret biophysical experiments. It is possible for users to book SPC equipment together with their synchrotron beamtime, for protein purification, circular dichroism and isothermal calorimetry. Funded access to the facility is currently provided by the European Community's Seventh Framework Programme Biostruct-X. For further information, please contact [email protected].

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Open discussion

Symposium - International Astronomical Union ◽

10.1017/s0074180900029533 ◽

1982 ◽

Vol 99 ◽

pp. 605-613

Author(s):

P. S. Conti

Keyword(s):

Buenos Aires ◽

Large Mass ◽

List Type ◽

Common Phenomenon ◽

Open Discussion ◽

The Stability ◽

Ring Nebulae

Conti: One of the main conclusions of the Wolf-Rayet symposium in Buenos Aires was that Wolf-Rayet stars are evolutionary products of massive objects. Some questions:–Do hot helium-rich stars, that are not Wolf-Rayet stars, exist?–What about the stability of helium rich stars of large mass? We know a helium rich star of ∼40 MO. Has the stability something to do with the wind?–Ring nebulae and bubbles : this seems to be a much more common phenomenon than we thought of some years age.–What is the origin of the subtypes? This is important to find a possible matching of scenarios to subtypes.

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Symmetric Multistep Methods Revisited: II. Numerical Experiments

International Astronomical Union Colloquium ◽

10.1017/s0252921100031602 ◽

1999 ◽

Vol 173 ◽

pp. 309-314 ◽

Cited By ~ 3

Author(s):

T. Fukushima

Keyword(s):

Multistep Methods ◽

Computational Time ◽

Integration Time ◽

Implicit Methods ◽

Symmetric Methods ◽

Celestial Bodies ◽

The Stability ◽

Predictor Corrector ◽

Symmetric Multistep Methods ◽

Integration Errors

AbstractBy using the stability condition and general formulas developed by Fukushima (1998 = Paper I) we discovered that, just as in the case of the explicit symmetric multistep methods (Quinlan and Tremaine, 1990), when integrating orbital motions of celestial bodies, the implicit symmetric multistep methods used in the predictor-corrector manner lead to integration errors in position which grow linearly with the integration time if the stepsizes adopted are sufficiently small and if the number of corrections is sufficiently large, say two or three. We confirmed also that the symmetric methods (explicit or implicit) would produce the stepsize-dependent instabilities/resonances, which was discovered by A. Toomre in 1991 and confirmed by G.D. Quinlan for some high order explicit methods. Although the implicit methods require twice or more computational time for the same stepsize than the explicit symmetric ones do, they seem to be preferable since they reduce these undesirable features significantly.

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Uniformity of Magnification from Different Electron Microscopes

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100060179 ◽

1967 ◽

Vol 25 ◽

pp. 32-33

Author(s):

Godfrey C. Hoskins ◽

V. Williams ◽

V. Allison

Keyword(s):

Diffraction Grating ◽

The Other ◽

Carbon Replica ◽

Electron Microscopes ◽

The Stability

The method demonstrated is an adaptation of a proven procedure for accurately determining the magnification of light photomicrographs. Because of the stability of modern electrical lenses, the method is shown to be directly applicable for providing precise reproducibility of magnification in various models of electron microscopes.A readily recognizable area of a carbon replica of a crossed-line diffraction grating is used as a standard. The same area of the standard was photographed in Phillips EM 200, Hitachi HU-11B2, and RCA EMU 3F electron microscopes at taps representative of the range of magnification of each. Negatives from one microscope were selected as guides and printed at convenient magnifications; then negatives from each of the other microscopes were projected to register with these prints. By deferring measurement to the print rather than comparing negatives, correspondence of magnification of the specimen in the three microscopes could be brought to within 2%.

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Effect of Improved ThO2 Particle Dispersion in Nickel on High-Temperature Strength

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100069211 ◽

1970 ◽

Vol 28 ◽

pp. 444-445

Author(s):

E. R. Kimmel ◽

H. L. Anthony ◽

W. Scheithauer

Keyword(s):

High Temperature ◽

Metal Matrix ◽

Oxide Particle ◽

Oxide Phase ◽

Dislocation Motion ◽

Particle Dispersion ◽

High Temperature Strength ◽

Strengthening Effect ◽

Oxide Particles ◽

The Stability

The strengthening effect at high temperature produced by a dispersed oxide phase in a metal matrix is seemingly dependent on at least two major contributors: oxide particle size and spatial distribution, and stability of the worked microstructure. These two are strongly interrelated. The stability of the microstructure is produced by polygonization of the worked structure forming low angle cell boundaries which become anchored by the dispersed oxide particles. The effect of the particles on strength is therefore twofold, in that they stabilize the worked microstructure and also hinder dislocation motion during loading.

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