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Objectives: To analyse the various methods for carbon dioxide absorption in anaesthesia, the available absorbents and their modes of use., Data Sources: We searched the Medline and Internet databases for papers using the key words: carbon dioxide absorption, soda-lime, zeolite. We also had correspondence and contacts with soda lime manufacturers., Study Selection: All types of articles containing data on CO2 absorption., Data Extraction: The articles were analysed for the benefits and adverse effects of the various absorbents., Data Synthesis: Carbon dioxide absorption enables the use of low flow anaesthesia, and a decreased consumption of medical gases and halogenated anaesthetics, as well as reduced pollution. Chemical absorbents (soda-lime and barium hydroxide lime (Baralyme) may produce toxic compounds: carbon monoxide with all halogenated anaesthetics and compound A with sevoflurane. Simple measures against desiccation of the lime prevent carbon monoxide production. The toxicity of compound A, shown in the rat, has not been proven in clinical anaesthesia. Recent improvements in manufacture processes have decreased the powdering of lime. Moreover, filters inserted between the anaesthesia circuit and the patient abolish the risk for powder inhalation.

The determination of carbon dioxide in carbonato-apatites is carried out a new gasometric method. Its application, in this paper, concerns the bones of skull and mandibles of Cory's shearwater (Calonectris diomedea borealis) and Mallard (Anas platyrhynchos). The results lead to appreciable differences between some organs of this two species.

Industrial ventilation takes into account the quality of the air inside the IAQ (Indoor Air Quality) and the degree of exposure of workers. In industrial targets the emission regime of contaminants can be 10–100 times higher than in non-industrial targets, but for many pollutants the IAQ levels can be the same. The parameters of the state of the air which are of interest for the technique of ventilation and air conditioning are: air temperature and humidity, atmospheric pressure and air speed. For the study on the variation of the air state parameters inside the industrial ventilation installations, in the experiment laboratory, on the study of the industrial ventilation systems, the experiment was performed on the variation of the air state parameters in the conditions of circulation through the ventilation duct. an amount of carbon dioxide. Prior to the introduction of carbon dioxide into the duct, the ventilation system was started, at nominal parameters. During the experiment, the operating parameters of the drive motor were changed using a frequency converter on levels 50; 40; 30; 20; 10 and 5 Hz. The ventilation system used was structured by means of flow converters which were fixed in the open position. The ventilation system as well as the flow variators were operated by the SCADA type command and control system The paper will present the analysis of the variation of state parameters (temperature, humidity, absolute pressure and air speed) by introducing a constant amount of carbon dioxide in the ventilation duct.

This paper reviews recent developments in the experimental approach to panic anxiety. Inhalation of carbon dioxide appears to trigger panic attacks in panic disorder patients and agoraphobics. The biological and psychopathological implications of this finding are discussed in the light of recent data on experimental pharmacology of anxiety.

Copyright of VertigO is the property of La Revue Electronique en Sciences de l'Environnement VertigO and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of VertigO is the property of La Revue Electronique en Sciences de l'Environnement VertigO and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Biotechnologie, Agronomie, Societe et Environnement is the property of Les Presses Agronomiques de Gembloux and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Increasing atmospheric level of greenhouse gases are causing global warming and putting at risk the global climate system. The main anthropogenic greenhouse gas is CO2. Technical solutions exist to reduce CO2 emission and stabilise atmospheric CO2 concentration, including energy saving and energy efficiency, switch to lower carbon content fuels like natural gas and to energy sources that operate with zero CO2 emissions such as renewable or nuclear energy, enhance the natural sinks for CO2 (forests, soils, etc.), and last but not least, sequester CO2 from fossil fuels combustion. The purpose of this paper is to provide an overview of the technology and cost for capture and storage of CO2. Some of the factors that will influence application, including environmental impact, cost and efficiency, are also discussed. Capturing CO2 and storing it in underground geological reservoirs appears as the best environmentally acceptable option. It can be done with existing technology; however, substantial R&D is needed to improve available technology and to lower the cost. Applicable to large CO2 emitting industrial facilities such as power plants, cement factories, steel industry, etc., which amount to more than 30% of the global anthropogenic CO2 emission, it represents a valuable tool in the battle against global warming. To cite this article: P. Jean-Baptiste, R. Ducroux, C. R. Geoscience 335 (2003). [Copyright &y& Elsevier]

The paper presents the results of theoretical and experimental analysis of a vacuum-freeze-drying refrigeration machine based on carbon dioxide. Such refrigeration machines can be equipped with refrigerators for the needs of medicine, where low temperatures are widely in demand in the range from minus 80 degrees Celsius to minus 130 degrees Celsius. The problem of developing alternative refrigeration machines is dictated by modern environmental requirements for working substances, which are gradually being tightened and soon the use of familiar freons will become impossible. For the air conditioning and commercial refrigeration industry, new substances are being actively developed, such as hydrofluoroolefins (HFOs), hydrocarbons can also serve as substitutes for hydrofluorocarbons and their mixtures, but it must be considered that they are combustible and explosive. A carbon dioxide vacuum sublimation unit may be an alternative to modern freon vapor compression refrigeration units for the indicated temperature range, but subject to comparable energy costs during its operation. The article examined the three-stage and four-stage cycles of a vacuum-freeze-drying refrigeration machine, conducted their theoretical comparison in terms of COP with a cascade cycle on hydrocarbon working substances. It can be noted that the COP of the considered cycles are close, but the environmental friendliness, safety and non-combustibility of carbon dioxide gives the advantages of a vacuum freeze-drying refrigeration machine.

Ionic liquids (ILs) are efficient solvents for the selective removal of CO2 from flue gas. Conventional, offthe-shelf ILs are limited in use to physisorption, which restricts their absorption capacity. After adding a chemical functionality like amines or alcohols, absorption of CO2 occurs mainly by chemisorption. This greatly enhances CO2 absorption and makes ILs suitable for potential industrial applications. By carefully choosing the anion and the cation of the IL, equimolar absorption of CO2 is possible. This paper reviews the current state of the art of CO2 capture by ILs and presents the current research in this field performed at the ChemTech Institute of the Ecole d'Ingénieurs et d'Architectes de Fribourg.

Copyright of Revue Française de Gestion is the property of John Libbey Eurotext Ltd. and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of VSE - Vie & Sciences Economiques / La revue de l'Economie et de l'Entreprise is the property of ANDESE and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Carbon capture and storage (CCS) combines several techniques in order to capture carbon dioxide emitted by industrial and energy production processes, transport it and store it in geological reservoirs, so as to isolate it from the atmosphere for long time periods. This technology was invented in the 1970s by researchers and industrialists. A few industrial projects applying CCS are today in different parts of the world. In the EU, a CCS policy emerged during the last decade. The European Commission, in partnership with industry players, has committed to a process of CCS "demonstration", aiming to develop 10 large-scale demonstrators by 2015. The emergence of EU CCS policy was marked by intense debates and local conflicts, especially with regard to the risks associated with potential leakages of CO2 in the short term (acidification of surface media or groundwater) or in the long term (CCS claimed to be ineffective in the fight against climate change). These discussions have also addressed the high cost and the relevance (end-of-pipe technology) of the CCS option in comparison with other CO2 mitigation options (reduction in energy demand, development of low-carbon energy technologies). This paper analyzes the relationship between CCS demonstration and the definition of the associated risks, by looking at the way in which protagonists involved in the CCS policy process resort to normative, stabilized or emerging risk frameworks.