Single step method for the accurate concentration determination of polysorbate 80

In order to determine the thermal diffusivity of materials, especially solids and liquids at high temperatures, two extended containerless flash techniques that are applicable to levitated spherical specimen are proposed. The extended flash methods are modeled as an axisymmetric transient conduction heat transfer problem within the sphere. For the “single-step” method, analytic expressions for the temperature history on the surface of the sphere are obtained that are independent of the incident energy and the absorption layer thickness. It is shown that by knowing the sample diameter and recording the temperature transient history at least at two different points on the surface simultaneously, the thermal diffusivity can be determined. A detailed discussion of the effects of the various parameters is presented. For the “two-step” analysis the problem of nonlinearity of the radiative heat transfer boundary condition is overcome by replacing it with the measured time-dependent surface temperature data. Upon obtaining the temperature field the determination of the thermal diffusivity turns into a minimization problem. In performing the proposed two-step procedure there is a need to undertake a cool-down experiment. Results of an experimental study directed at determining the thermal diffusivity of high-temperature solid samples of pure Nickel and Inconel 718 superalloy near their melting temperatures using the single-step method are discussed. Based on close agreement with reliable data available in the literature, it is concluded that the proposed techniques can provide reliable thermal diffusivity data for high-temperature materials.

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A simple and sensitive single-step method for gas chromatography–mass spectrometric determination of fipronil and its metabolites in sugarcane juice, jaggery and sugar

Food Chemistry ◽

10.1016/j.foodchem.2013.11.004 ◽

2014 ◽

Vol 150 ◽

pp. 408-413 ◽

Cited By ~ 23

Author(s):

Thirumalaiandi Ramasubramanian ◽

Mariappan Paramasivam ◽

Ramabhadran Jayanthi ◽

Subramaniam Chandrasekaran

Keyword(s):

Gas Chromatography ◽

Single Step ◽

Mass Spectrometric ◽

Sugarcane Juice ◽

Step Method ◽

Mass Spectrometric Determination

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A single-step method for determination of the specific radioactivity of lipids

Lipids ◽

10.1007/bf02535838 ◽

1980 ◽

Vol 15 (4) ◽

pp. 269-271 ◽

Cited By ~ 3

Author(s):

R. C. Noble ◽

J. H. Shand

Keyword(s):

Specific Radioactivity ◽

Single Step ◽

Step Method

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Concentration determination of chromatin in unstained resin-embedded sections by means of Z-contrast in STEM

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100134521 ◽

1990 ◽

Vol 48 (2) ◽

pp. 186-187

Author(s):

M. Haider ◽

B. Bohrmann

Keyword(s):

Energy Loss ◽

Freeze Substitution ◽

Biological Macromolecules ◽

Local Concentration ◽

E Coli ◽

Concentration Determination ◽

Phosphorous Content ◽

Z Contrast ◽

Electron Energy Loss

The technique of Z-contrast in STEM offers the possibility to determine the local concentration of macromolecules like lipids, proteins or DNA. Contrast formation depends on the atomic composition of the particular structure. In the case of DNA, its phosphorous content discriminates it from other biological macromolecules. In our studies, sections of E. coli, the dinoflagellate Amphidinium carterae and Euglena spec. cells were used which were obtained by cryofixation followed by freeze-substitution into acetone with 3% glutaraldehyde. The samples were then embedded either in Lowicryl HM20 at low temperature or in Epon at high temperature. Sections were coated on both sides with 30Å carbon.The DF- and the inelastic image have been recorded simultaneously with a Cryo-STEM. This Cryo-STEM is equipped with a highly dispersive Electron Energy Loss Spectrometer. With this instrument pure Z-contrast can be achieved either with a Filtered DF-image divided by the inelastic image or, as is used in this paper, by dividing the conventional DF-image by an inelastic image which has been recorded with an inelastic detector whose response is dependent on the total energy loss of the inelastically scattered electrons.

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Purification of Urokinase from Complex Mixtures Using Immobilized Monoclonal Antibody Against Urokinase Light Chain

Thrombosis and Haemostasis ◽

10.1055/s-0038-1657308 ◽

1983 ◽

Vol 49 (01) ◽

pp. 024-027 ◽

Cited By ~ 20

Author(s):

David Vetterlein ◽

Gary J Calton

Keyword(s):

Monoclonal Antibody ◽

Light Chain ◽

Culture Media ◽

Biological Fluids ◽

Single Step ◽

High Yield ◽

Step Method ◽

Commercial Preparation ◽

E Coli ◽

Tissue Culture Media

SummaryThe preparation of a monoclonal antibody (MAB) against high molecular weight (HMW) urokinase light chain (20,000 Mr) is described. This MAB was immobilized and the resulting immunosorbent was used to isolate urokinase starting with an impure commercial preparation, fresh urine, spent tissue culture media, or E. coli broth without preliminary dialysis or concentration steps. Monospecific antibodies appear to provide a rapid single step method of purifying urokinase, in high yield, from a variety of biological fluids.

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