A study of the process of pyrolysis in a water-vapor stream of activated carbons, prepared from agricultural by-products by some physico-chemical methods

1994 ◽  
Vol 244 ◽  
pp. 267-276 ◽  
Author(s):  
T. Budinova ◽  
K. Gergova ◽  
N. Petrov ◽  
V. Minkova
Keyword(s):  
Water Vapor ◽  
Activated Carbons ◽  
Chemical Methods ◽  
Physico Chemical ◽  
Vapor Stream ◽  
By Products

scholarly journals Potential of white-rot fungi for bioremediation

2017 ◽  
Vol 4 (7) ◽  
pp. 229-232 ◽  
Author(s):  
Ronivaldo Rodrigues da Silva
Keyword(s):  
Waste Treatment ◽  
White Rot Fungi ◽  
White Rot ◽  
Toxic Substances ◽  
Chemical Methods ◽  
Fungal Enzymes ◽  
Mild Conditions ◽  
Environmental Friendly ◽  
Physico Chemical ◽  
By Products

Environmental applications of enzymes in biodegradation for preventing pollution by toxic byproducts warrants approaches that can be performed under mild conditions, are economically feasible and can replace the use of chemicals. Technologies involving physico-chemical methods, like incineration, dechlorination and UV oxidation, for waste treatment are not acceptable since they generate a lot of pollutants as by-products. To address these problems, environmental–friendly alternatives are required for bioremediation. In this context, fungal enzymes have emerged as a natural tool to detoxification of pollutants in environment, and the potential to convert toxic substances to less hazardous or non-hazardous forms. However, what are the effective advances by using white-rot fungi for bioremediation? Here, a brief discussion about the application of these fungi to detoxification of pollutants in environment has been considered.

scholarly journals Valorisation of Coffee Roasting By-Products: Recovery of Silverskin Fat By Supercritical CO2 Extraction

2021 ◽  
Author(s):  
Rita Nasti ◽  
Andrea Galeazzi ◽  
Stefania Marzorati ◽  
Federica Zaccheria ◽  
Nicoletta Ravasio ◽  
...  
Keyword(s):  
Scale Up ◽  
Added Value ◽  
Supercritical Co2 Extraction ◽  
Green Technologies ◽  
Coffee Silverskin ◽  
New Concepts ◽  
Physico Chemical ◽  
High Investment ◽  
Fat Yield ◽  
By Products

AbstractRecovery of agro and food-industrial waste and their valorisation via green technologies can help to outline new concepts of industrial strategies. In this contest, a fat enriched of added-value components was extracted from coffee silverskin by applying a supercritical fluid extraction technique (sc-CO2). An appropriate modulation of process parameters like temperature (T = 35, 50, 60 °C) and pressure (p = 200–300 bar) influences the fat yield and the chemical composition, opening the way for targeted extraction. The extraction time, the organic solvent use and the energy consume were reduced compared to Soxhlet. Moreover, a mathematical model was constructed based on the experimental data collected, employed apparatus, and physico-chemical characteristics of biomass, pointing to a possible industrial scale-up. The experimental results are accompanied by a preliminary cost of manufacturing (COM), highlighting how the high investment for the apparatus is compensated by several benefits. Graphic Abstract

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.

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