Physico-Chemical Methods to Control Zirconia Powders

Zirconia’88 ◽  
1989 ◽  
pp. 219-228
Author(s):  
P. Orlans ◽  
L. Montanaro ◽  
J. P. Lecompte ◽  
B. Guilhot ◽  
A. Negro
Keyword(s):  
Chemical Methods ◽  
Physico Chemical ◽  
Zirconia Powders

scholarly journals Contribution of Nanomaterials to the Development of Electrochemical Aptasensors for the Detection of Antimicrobial Residues in Food Products

Chemosensors ◽  
2021 ◽  
Vol 9 (4) ◽  
pp. 69
Author(s):  
Valérie Gaudin
Keyword(s):  
Signal Amplification ◽  
Electrochemical Sensors ◽  
Low Cost ◽  
Food Products ◽  
Animal Origin ◽  
Screening Methods ◽  
Chemical Methods ◽  
Portable Instrumentation ◽  
Physico Chemical ◽  
Antimicrobial Residues

The detection of antimicrobial residues in food products of animal origin is of utmost importance. Indeed antimicrobial residues could be present in animal derived food products because of animal treatments for curative purposes or from illegal use. The usual screening methods to detect antimicrobial residues in food are microbiological, immunological or physico-chemical methods. The development of biosensors to propose sensitive, cheap and quick alternatives to classical methods is constantly increasing. Aptasensors are one of the major trends proposed in the literature, in parallel with the development of immunosensors based on antibodies. The characteristics of electrochemical sensors (i.e., low cost, miniaturization, and portable instrumentation) make them very good candidates to develop screening methods for antimicrobial residues in food products. This review will focus on the recent advances in the development of electrochemical aptasensors for the detection of antimicrobial residues in food products. The contribution of nanomaterials to improve the performance characteristics of electrochemical aptasensors (e.g., Sensitivity, easiness, stability) in the last ten years, as well as signal amplification techniques will be highlighted.

scholarly journals The principle of formaldehyde, alcohol, and acetone titrations. With a discussion of the proof and implication of the zwitterion conception

1934 ◽  
Vol 115 (792) ◽  
pp. 121-141 ◽  
Keyword(s):  
Amino Acids ◽  
Carboxyl Groups ◽  
Recent Discussion ◽  
Amino Groups ◽  
Chemical Methods ◽  
Titration Method ◽  
Physico Chemical ◽  
Empirical Argument ◽  
Chemical Evidence

Consideration of the implications of the zwitterion hypothesis of Bjerrum (1923) makes it desirable to state afresh the principles underlying the methods commonly employed in the titration of amino-acids. Deductions of considerable theoretical importance, cf., e. g ., Calvery (1933) are still being made on the supposition that the alkalimetric formaldehyde titration method of Sørensen (1907) and the corresponding alcohol method of Foreman (1920) and of Willstätter and Waldschmidt-Leitz (1921) estimate the carboxyl groups of amino-acids whilst the acidimetric acetone titration of Linderstrøm-Lang (1928) estimates the amino-groups. Yet the zwitterion hypothesis indicates that this assumption is the reverse of the truth. Discussion is greatly facilitated by collective consideration of recent physico-chemical evidence clarifying the principles upon which these common bio-chemical methods rest. In a recent discussion of two of the titrimetric methods (Van Slyke and Kirk, 1933) the existence of this evidence is ignored, so that it becomes necessary to systematize and elaborate the empirical argument of these authors in the light of the relevant investigations of Grünhut (1919), Cray and Westrip (1925), Michaelis and Mizutani (1925), Birch and Harris (1930, b ), and Levy (1933). At the same time new and useful developments are indicated.

scholarly journals A Review - Carisoprodol as Skeletal Muscle Relaxant

2020 ◽  
pp. 40-44
Author(s):  
A. A Patil ◽  
M. K. Shirsat ◽  
V. R. Salunkhe
Keyword(s):  
Skeletal Muscle ◽  
Allocation Concealment ◽  
Muscle Relaxants ◽  
Chemical Methods ◽  
Physiochemical Properties ◽  
Musculoskeletal Conditions ◽  
Intention To Treat ◽  
Physico Chemical ◽  
Derivatives Of ◽  
Host Target

In the world of pharmacology, the prescription of a medicine and its dosage play important role. Different physico-chemical methods are in vogue in describing the interactions of the drug molecule with host target among them, the chief being spectroscopic, chromatographic and quantum mechanical techniques. Skeletal muscle relaxants are divided into two categories: antispastic (for conditions such as cerebral palsy and multiple sclerosis) and antispasmodic agents (for musculoskeletal conditions). Antispastic agents (e.g., baclofen [Lioresal], dantrolene [Dantrium]) should not be prescribed for musculoskeletal conditions because there is sparse evidence to support their use. Rather, anantispasmodic agent may be more appropriate Many of the studies evaluating the effectiveness of skeletal muscle relaxants are hampered by poor methodologic design, including incomplete reporting of compliance, improper or no mention of allocation concealment, not utilizing intention-to-treat methods, and inadequate randomization. skeletal muscle relaxants have been evaluated in systematic reviews and meta-analyses.These include Methocarbamol, Meprobamate, Metaxalone, Carisoprodol, Dantrium and Baclofen. Chemically Carisoprodol is N-isopropyl-2-methyl-2-propyl-1,3-propanediol dicarbamate. Methods like nitration, Sulphonation, Methylation, Esterification, Acetylation and Diazotization was used for formation of new derivative which can be detected in UV region. Different reactions of diazotization were used for getting a new and novel derivative of Carisoprodol. Physiochemical properties, TLC, UV, IR and NMR analysis of Carisoprodol and newly obtained derivatives of Carisoprodol was studied and it showed that there was change in color, odour, taste, melting point, solubility pattern of original drug and derivatives.

Bulk and surface characterization of laterite by various physico-chemical methods

1987 ◽  
Vol 19 (1-4) ◽  
pp. 43-67 ◽  
Author(s):  
Ranen Sen ◽  
Katsuyuki Takahashi ◽  
Randy Fortin ◽  
David J. Spottiswood ◽  
Baki Yarar
Keyword(s):  
Surface Characterization ◽  
Chemical Methods ◽  
Physico Chemical

scholarly journals Investigation of geographic origin of wine from border regions: Results from investigation of two vintages

2019 ◽  
Vol 15 ◽  
pp. 02039
Author(s):  
M. Horacek ◽  
M. Hola ◽  
B. Tobolkova ◽  
K. Kolar ◽  
T. Vaculovic ◽  
...  
Keyword(s):  
Geographic Origin ◽  
Agricultural Practices ◽  
Data Sets ◽  
Chemical Methods ◽  
Border Regions ◽  
Physico Chemical ◽  
Icp Ms ◽  
Increased Sensitivity ◽  
Border Areas ◽  
Combination Of Methods

Investigation on discrimination of geographic origin in border areas is carried out by investigating and comparing authentic wine samples from the border areas of Austria, Czech Republic, Slovakia (and from Serbia) by applying different physico-chemical methods (e.g. IRMS, NMR, ICP-MS, ICP-OES, EPR, HPLC, UV-VIS, etc…). The comparison of the data sets from the participating countries and the different applied methods demonstrates, to which extent a differentiation can still be achieved in the border areas of the respective countries, which methods prove most efficient and sensitive and if a combination of methods leads to an increased sensitivity. Furthermore, we also investigate the potential causes for the differentiation, as the environment, different agricultural practices or enology. Analysis of two consecutive vintages shows significant variations between the two years, complicating direct comparison of regions beyond individual vintages. Still, several parameters are identified enabling correct and complete differentiation. However, some of them have been found to represent lab effects, whereas others are interpreted as resulting from different agricultural practices or environmentally driven. Only the latter two ones, if consistent, can be used for discrimination of geographic origin.

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