Academic literature on the topic 'Gravimetrically'
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Journal articles on the topic "Gravimetrically"
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PROEBSTLE, T. M., V. SCHNEIDERS, and J. KNOP. "Gravimetrically Controlled Efficacy of Subcorial Curettage." Dermatologic Surgery 28, no. 11 (2002): 1022–26. http://dx.doi.org/10.1097/00042728-200211000-00010.
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Futa, A., M. Jastrzębska, and Z. Suchorab. "Comparison of regression models of linear and polynomial dependencies in moisture detection technique." Journal of Physics: Conference Series 2628, no. 1 (2023): 012005. http://dx.doi.org/10.1088/1742-6596/2628/1/012005.
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Abstract The article presents the description of moisture detection technique in building materials and comparison of two techniques of analysis. More precisely, two models of linear regression, with linear and polynomial dependencies are presented. The readouts present the dependence between the moisture of ceramic brick, evaluated gravimetrically and permittivity values determined by TDR technique. The correlation between the moisture content estimated by the TDR and the moisture content determined gravimetrically is shown. Using the achieved data, regression models are compared and the quality of both models is determined.
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(MS.), S. G. KAWATKAR, and V. NIMBALKAR RAMCHANDRA. "Spectrophotometric Determination of Palladium(II) with 5-Chlorosalicylaldehyde Guanylhydrazone." Journal of Indian Chemical Society Vol. 74, Jan 1997 (1997): 69. https://doi.org/10.5281/zenodo.5878191.
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Department of Chemistry, Shivaji University. Kolhapur-416 004 Department of Chemistry, Mudhoji College, Phaltan (Satara)-415 523 <em>Manuscript received 9 June 1994. revised 26 May 1995, accepted 20 June 1995</em> Spectrophotometric Determination of Palladium(II) with 5-Chlorosalicylaldehyde Guanylhydrazone
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Josephs, R. D., M. Bedu, A. Daireaux, et al. "Key Comparison Study - Organic Solvent Calibration Solution - Gravimetric preparation and value assignment of aflatoxin B1 (AfB1) in acetonitrile (ACN)." Metrologia 59, no. 1A (2022): 08002. http://dx.doi.org/10.1088/0026-1394/59/1a/08002.
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Main text The CCQM-K154.b comparison was coordinated by the Bureau International des Poids et Mesures (BIPM) and the Chinese National Institute of Metrology (NIM) on behalf of the Organic Analysis Working Group (OAWG) of the Comité Consultatif pour la Quantité de Matière (CCQM) for National Measurement Institutes (NMIs) and Designated Institutes (DIs) which provide measurement services in organic analysis under the 'Comité International des Poids et Mesures' Mutual Recognition Arrangement (CIPM MRA) and/or have participated in the BIPM's Mycotoxin Metrology Capacity Building and Knowledge Transfer (MMCBKT) project as part of its "Metrology for Safe Food and Feed in Developing Economies" Capacity Building Programme. Gravimetrically-prepared solutions having an assigned mass fraction of specified organic analytes are routinely used to calibrate measurement processes for the quantification of the same analytes in matrix samples. Appropriate assignments of the property value and associated uncertainty of calibration solutions thus underpin the traceability of routine analysis and are critical for accurate measurements. Evidence of successful participation in relevant international comparisons is needed to document calibration and measurement capability claims (CMCs) made by national metrology institutes and designated institutes. In total, eleven NMIs/DIs participated in the Track C, Model II, Key Comparison CCQM-K154.b [Gravimetric preparation and value assignment of aflatoxin B1 (AfB1) in acetonitrile (ACN)] for emerging areas of global interest and innovation. Participants were requested to gravimetrically prepare calibration solutions and value assign the mass fractions, expressed in mg/kg, of aflatoxin B1 (AfB1) in the acetonitrile (ACN) solution. Study samples, with assigned values and associated uncertainties were prepared by the comparison participants and sent to the coordinating laboratory for comparison. The Key Comparison Reference Values (KCRVs), calculated form values measured by the coordinating laboratory based on calibrations obtained from independent gravimetrically prepared calibrant solutions, agreed with participants reported values, within their stated uncertainties. AfB1 was selected to be representative of polar aflatoxins. Aflatoxins are a class of mycotoxins generally produced by fungi of the genus Aspergillus. It was anticipated to provide a challenge representative for the gravimetrical preparation and value assignment of calibration solutions in the mass fraction range of 2 mg/kg to 50 mg/kg of mycotoxins with broadly similar structural characteristics. Nine participants of the MMCBKT programme were provided with a stock solution having a known AfB1 mass fraction and expanded uncertainty to use to gravimetrically prepare and value assign a calibration solution. Three NMIs/DIs also participated using their own calibration solutions. The use of in-house solutions required an additional capacity to undertake a fit-for-purpose purity assessment. NIM was the only NMI participating using both the MMCBKT based and their own in-house assigned solutions in order to connect the two different groups. It was decided to propose separate KCRVs for each of the two ampoules provided by the participating NMIs/DIs based on the AfB1 mass fraction. This allowed participants to demonstrate the efficacy of their implementation of the approaches used to gravimetrically prepare calibration solutions and to assess the AfB1 mass fraction. The majority of the AfB1 mass fraction KCRVs (wKCRV) for CCQM-K154.b spanned a mass fraction range of 2.02 mg/kg to 31.57 mg/kg. The relative expanded uncertainties U(wKCRV) ranged from 0.69 % to 2.93 %. Inspection of the degree of equivalence plots for the AfB1 mass fraction assignments in CCQM-K154.b indicated that there was an excellent agreement of results. Solely, the AfB1 mass fraction assignments of INRAP did not agree with the KCRVs. It was found that the samples were altered as a result of an acid contamination. To reach the main text of this paper, click on Final Report. Note that this text is that which appears in Appendix B of the BIPM key comparison database https://www.bipm.org/kcdb/. The final report has been peer-reviewed and approved for publication by the CCQM, according to the provisions of the CIPM Mutual Recognition Arrangement (CIPM MRA).
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Josephs, R. D., M. Bedu, A. Daireaux, et al. "Key comparison study - organic solvent calibration solution - gravimetric preparation and value assignment of deoxynivalenol (DON) in acetonitrile (ACN)." Metrologia 60, no. 1A (2022): 08002. http://dx.doi.org/10.1088/0026-1394/60/1a/08002.
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Main text The CCQM-K154.c comparison was coordinated by the the Bureau International des Poids et Mesures (BIPM) and the Chinese National Institute of Metrology (NIM) on behalf of the Organic Analysis Working Group (OAWG) of the Comité Consultatif pour la Quantité de Matière (CCQM) for National Measurement Institutes (NMIs) and Designated Institutes (DIs) which provide measurement services in organic analysis under the 'Comité International des Poids et Mesures' Mutual Recognition Arrangement (CIPM MRA) and/or have participated in the BIPM's Mycotoxin Metrology Capacity Building and Knowledge Transfer (MMCBKT) project as part of its "Metrology for Safe Food and Feed in Developing Economies" Capacity Building Programme. Gravimetrically-prepared solutions having an assigned mass fraction of specified organic analytes are routinely used to calibrate measurement processes for the quantification of the same analytes in matrix samples. Appropriate assignments of the property value and associated uncertainty of calibration solutions thus underpin the traceability of routine analysis and are critical for accurate measurements. Evidence of successful participation in relevant international comparisons is needed to document calibration and measurement capability claims (CMCs) made by national metrology institutes and designated institutes. In total, nine NMIs/DIs participated in the Track C, Model II, Key Comparison CCQM-K154.c [Gravimetric preparation and value assignment of deoxynivalenol (DON) in acetonitrile (ACN)] for emerging areas of global interest and innovation. Participants were requested to gravimetrically prepare calibration solutions and value assign the mass fractions, expressed in mg/kg, of deoxynivalenol (DON) in the acetonitrile (ACN) solution. Study samples, with assigned values and associated uncertainties were prepared by the comparison participants and sent to the coordinating laboratory for comparison. The Key Comparison Reference Values (KCRVs), calculated from values measured by the coordinating laboratory based on calibrations obtained from independent gravimetrically prepared calibrant solutions, agreed with participants reported values, within their stated uncertainties. DON belongs to the large group of trichothecene mycotoxins. It is produced by certain fungi of the genus Fusarium that predominantly infect wheat, corn, oats, barley, rice, and other grains in the field or during storage. It was anticipated to provide a challenge representative for the gravimetrical preparation and value assignment of calibration solutions in the mass fraction range of 10 mg/kg to 100 mg/kg of mycotoxins with broadly similar structural characteristics. Ten participants of the MMCBKT programme were provided with a stock solution having a known DON mass fraction and expanded uncertainty to use to gravimetrically prepare and value assign a calibration solution. Three NMIs/DIs also participated using their own calibration solutions. The use of in-house solutions required an additional capacity to undertake a fit-for-purpose purity assessment. NIM was the only NMI participating using both the MMCBKT based and their own in-house assigned solutions in order to connect the two different groups. It was decided to propose separate KCRVs for each of the two ampoules provided by the participating NMIs/DIs based on the DON mass fraction. This allowed participants to demonstrate the efficacy of their implementation of the approaches used to gravimetrically prepare calibration solutions and to assess the DON mass fraction. The majority of the DON mass fraction KCRVs (w KCRV ) for CCQM-K154.c spanned a mass fraction range of 9.88 mg/kg to 123.45 mg/kg. The relative expanded uncertainties U(w KCRV ) ranged from 2.8 % to 6.8 %. Inspection of the degree of equivalence plots for the DON mass fraction assignments in CCQM-K154.c indicated that there was an excellent agreement of results. To reach the main text of this paper, click on Final Report. Note that this text is that which appears in Appendix B of the BIPM key comparison database https://www.bipm.org/kcdb/. The final report has been peer-reviewed and approved for publication by the CCQM, according to the provisions of the CIPM Mutual Recognition Arrangement (CIPM MRA).
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Futa, A., and M. Jastrzębska. "The comparison of two polynomial regression models with one and two independent variables in moisture detection technique in building materials." Journal of Physics: Conference Series 2911, no. 1 (2024): 012033. https://doi.org/10.1088/1742-6596/2911/1/012033.
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Abstract The paper presents the depiction of moisture detection technique in building materials and contains two techniques of analysis including a detailed comparison of them. Namely, two models of polynomial regression models are presented: the first model with one independent variable and the second, multiple regression model, including two independent variables. The readouts describe the dependence between the moisture of building material evaluated gravimetrically and permittivity and signal voltage values designate by TDR technique. The correlation between the moisture content determined by the TDR and the moisture content appointed gravimetrically is presented. Based on the obtained data, two types of regression models are compared. The property and the quality of both models are discussed.
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Josephs, R. D., M. Bedu, A. Daireaux, et al. "Subsequent Bilateral Key Comparison Study - Organic Solvent Calibration Solution - Gravimetric preparation and value assignment of aflatoxin B1 (AfB1) in acetonitrile (ACN)." Metrologia 61, no. 1A (2024): 08004. http://dx.doi.org/10.1088/0026-1394/61/1a/08004.
Full textAbstract:
Main text The original CCQM-K154.b comparison was coordinated by the Bureau International des Poids et Mesures (BIPM) and the Chinese National Institute of Metrology (NIM) on behalf of the Organic Analysis Working Group (OAWG) of the Comité Consultatif pour la Quantité de Matière (CCQM) for National Measurement Institutes (NMIs) and Designated Institutes (DIs) which provide measurement services in organic analysis under the 'Comité International des Poids et Mesures' Mutual Recognition Arrangement (CIPM MRA) and/or have participated in the BIPM's Mycotoxin Metrology Capacity Building and Knowledge Transfer (MMCBKT) project as part of its "Metrology for Safe Food and Feed in Developing Economies" Capacity Building Programme. Gravimetrically-prepared solutions having an assigned mass fraction of specified organic analytes are routinely used to calibrate measurement processes for the quantification of the same analytes in matrix samples. Appropriate assignments of the property value and associated uncertainty of calibration solutions thus underpin the traceability of routine analysis and are critical for accurate measurements. Evidence of successful participation in relevant international comparisons is needed to document calibration and measurement capability claims (CMCs) made by national metrology institutes and designated institutes. In total, eleven NMIs/DIs participated in the Track C, Model II, Key Comparison CCQM-K154.b [Gravimetric preparation and value assignment of aflatoxin B1 (AfB1) in acetonitrile (ACN)] for emerging areas of global interest and innovation. Participants were requested to gravimetrically prepare calibration solutions and value assign the mass fractions, expressed in mg/kg, of aflatoxin B1 (AfB1) in the acetonitrile (ACN) solution. Study samples, with assigned values and associated uncertainties were prepared by the comparison participants and sent to the coordinating laboratory for comparison. The Key Comparison Reference Values (KCRVs), calculated form values measured by the coordinating laboratory based on calibrations obtained from independent gravimetrically prepared calibrant solutions, agreed with participants reported values, within their stated uncertainties. AfB1 was selected to be representative of polar aflatoxins. Aflatoxins are a class of mycotoxins generally produced by fungi of the genus Aspergillus. It was anticipated to provide a challenge representative for the gravimetrical preparation and value assignment of calibration solutions in the mass fraction range of 2 mg/kg to 50 mg/kg of mycotoxins with broadly similar structural characteristics. In the original study CCQM-K154.b, nine participants of the MMCBKT programme were provided with a stock solution having a known AfB1 mass fraction and expanded uncertainty to use to gravimetrically prepare and value assign a calibration solution. Three NMIs/DIs also participated using their own calibration solutions. The use of in-house solutions required an additional capacity to undertake a fit-for-purpose purity assessment. NIM was the only NMI participating using both the MMCBKT based and their own in-house assigned solutions in order to connect the two different groups. It was decided to propose separate KCRVs for each of the two ampoules provided by the participating NMIs/DIs based on the AfB1 mass fraction. This allowed participants to demonstrate the efficacy of their implementation of the approaches used to gravimetrically prepare calibrations solutions and to assess the AfB1 mass fraction. The majority of the AfB1 mass fraction KCRVs (wKCRV) for CCQM-K154.b spanned a mass fraction range of 2.02 mg/kg to 31.57 mg/kg. The relative expanded uncertainties U(wKCRV) ranged from 0.69 % to 2.93 %. Inspection of the degree of equivalence plots for the AfB1 mass fraction assignments in CCQM-K154.b indicated that there was an excellent agreement of results. Solely, the AfB1 mass fraction assignments of the INRAP (Institut National de Recherche et d'Analyse Physico-Chimique, Tunisia) did not agree with the KCRVs. It was found that the samples were altered as a result of an acid contamination. The INRAP has produced a new batch of AfB1 calibration solution using the AfB1 stock solution originally provided to MMCBKT participants to be able to demonstrate the efficacy of their implementation of the approaches used to gravimetrically prepare calibrations solutions and to assess the AfB1 mass fraction. The BIPM organized the present subsequent bilateral comparison CCQM-K154.b.1 to assess the new batch of AfB1 calibration solution of the INRAP. Inspection of the degree of equivalence plots for the AfB1 mass fraction assignments indicated that there is an excellent agreement of the INRAP results for CCQM-K154.b.1. To reach the main text of this paper, click on Final Report. Note that this text is that which appears in Appendix B of the BIPM key comparison database https://www.bipm.org/kcdb/. The final report has been peer-reviewed and approved for publication by the CCQM, according to the provisions of the CIPM Mutual Recognition Arrangement (CIPM MRA).
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Hall, Bradley D., Andrew M. Crotwell, Benjamin R. Miller, Michael Schibig, and James W. Elkins. "Gravimetrically prepared carbon dioxide standards in support of atmospheric research." Atmospheric Measurement Techniques 12, no. 1 (2019): 517–24. http://dx.doi.org/10.5194/amt-12-517-2019.
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Abstract. We have explored a one-step method for gravimetric preparation of CO2-in-air standards in aluminum cylinders. We consider both adsorption to stainless steel surfaces used in the transfer of highly pure CO2 and adsorption of CO2 to cylinder walls. We demonstrate that CO2-in-air standards can be prepared with relatively low uncertainty (∼ 0.04 %, ∼95 % confidence level) by introducing aliquots whose masses are known to high precision and by using well-characterized cylinders. Five gravimetric standards, prepared over the nominal range of 350 to 490 µmol mol−1 (parts per million, ppm), showed excellent internal consistency, with residuals from a linear fit equal to 0.05 ppm. This work compliments efforts to maintain the World Meteorological Organization, Global Atmosphere Watch, mole fraction scale for carbon dioxide in air, widely used for atmospheric monitoring. This gravimetric technique could be extended to other atmospheric trace gases, depending on the vapor pressure of the gas.
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Josephs, R. D., M. Bedu, A. Daireaux, et al. "Key Comparison Study - Organic Solvent Calibration Solution - Gravimetric preparation and value assignment of patulin (PAT) in acetonitrile (ACN) with 0.1 % formic acid (FA)." Metrologia 60, no. 1A (2023): 08023. http://dx.doi.org/10.1088/0026-1394/60/1a/08023.
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Main text The CCQM-K154.d comparison was coordinated by the the Bureau International des Poids et Mesures (BIPM) and the Chinese National Institute of Metrology (NIM) on behalf of the Organic Analysis Working Group (OAWG) of the Comité Consultatif pour la Quantité de Matière (CCQM) for National Measurement Institutes (NMIs) and Designated Institutes (DIs) which provide measurement services in organic analysis under the 'Comité International des Poids et Mesures' Mutual Recognition Arrangement (CIPM MRA) and/or have participated in the BIPM's Mycotoxin Metrology Capacity Building and Knowledge Transfer (MMCBKT) project as part of its "Metrology for Safe Food and Feed in Developing Economies" Capacity Building Programme. Gravimetrically-prepared solutions having an assigned mass fraction of specified organic analytes are routinely used to calibrate measurement processes for the quantification of the same analytes in matrix samples. Appropriate assignments of the property value and associated uncertainty of calibration solutions thus underpin the traceability of routine analysis and are critical for accurate measurements. Evidence of successful participation in relevant international comparisons is needed to document calibration and measurement capability claims (CMCs) made by national metrology institutes and designated institutes. In total, twelve NMIs/DIs participated in the Track C, Model II, Key Comparison CCQM-K154.d [Gravimetric preparation and value assignment of patulin (PAT) in acetonitrile (ACN) with 0.1 % formic acid (FA)] for emerging areas of global interest and innovation. Participants were requested to gravimetrically prepare calibration solutions and value assign the mass fractions, expressed in mg/kg, of PAT in ACN with 0.1 % FA solution. Study samples, with assigned values and associated uncertainties were prepared by the comparison participants and sent to the coordinating laboratory for comparison. The Key Comparison Reference Values (KCRVs), calculated form values measured by the coordinating laboratory based on calibrations obtained from independent gravimetrically prepared calibrant solutions, agreed with participants reported values, within their stated uncertainties. PAT is a mycotoxin produced by a variety of moulds, particularly by fungi of the genus Aspergillus and Penicillium. Often found in rotting apples and apple products, PAT can also occur in various other moldy fruits, grains and foods. Major human dietary sources of PAT are apples and apple juice made from affected fruit. PAT is relatively stable when given a short-acting heat-treatment, especially in an acidic environment. It was anticipated to provide a challenge representative for the gravimetrical preparation and value assignment of PAT calibration solutions in the mass fraction range of 10 mg/kg to 100 mg/kg of mycotoxins with broadly similar structural characteristics. Eight participants of the MMCBKT programme were provided with a stock solution having a known PAT mass fraction and expanded uncertainty to use to gravimetrically prepare and value assign a calibration solution. Two NMIs/DIs used reference materials for preparing their solutions while five NMIs/DIs participated using their own calibration solutions. The use of in-house solutions required an additional capacity to undertake a fit-for-purpose purity assessment. NIM was the only NMI participating using both the MMCBKT based and their own in-house assigned solutions in order to connect the two different groups. It was decided to propose separate KCRVs for each of the two ampoules provided by the participating NMIs/DIs based on the PAT mass fraction. This allowed participants to demonstrate the efficacy of their implementation of the approaches used to gravimetrically prepare calibration solutions and to assess the PAT mass fraction. The majority of the PAT mass fraction KCRVs (wKCRV) for CCQM-K154.d spanned a mass fraction range of 9.72 mg/kg to 63.40 mg/kg. The relative expanded uncertainties U(wKCRV) ranged from 2.0 % to 5.4 %. Inspection of the degree of equivalence plots for the PAT mass fraction assignments in CCQM-K154.d indicated that there was an excellent agreement of results. To reach the main text of this paper, click on Final Report. Note that this text is that which appears in Appendix B of the BIPM key comparison database https://www.bipm.org/kcdb/. The final report has been peer-reviewed and approved for publication by the CCQM, according to the provisions of the CIPM Mutual Recognition Arrangement (CIPM MRA).
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Castillo, Maximiliano, Alejandro J. Metta-Magaña, and Skye Fortier. "Isolation of gravimetrically quantifiable alkali metal arenides using 18-crown-6." New Journal of Chemistry 40, no. 3 (2016): 1923–26. http://dx.doi.org/10.1039/c5nj02841h.
Full textDissertations / Theses on the topic "Gravimetrically"
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Fehrenbach, Antonia, Heinz Fehrenbach, Thorsten Wittwer, Matthias Ochs, Thorsten Wahlers, and Joachim Richter. "Evaluation of Pulmonary Edema: Stereological versus Gravimetrical Analysis." Saechsische Landesbibliothek- Staats- und Universitaetsbibliothek Dresden, 2014. http://nbn-resolving.de/urn:nbn:de:bsz:14-qucosa-132491.
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Assessment of lung edema by gravimetrical analysis is a standard method to evaluate the severity of experimentally induced ischemia/reperfusion (IR) injury. The aim of this study was to compare gravimetrical assessment of pulmonary edema with a stereological approach which allows for qualitative and quantitative distinction between intravascular and edematous fluids by light microscopy. Eight experimental groups which differed in mode of preservation, ischemic storage and pharmacological treatments were studied in an extracorporeal rat lung model. Analysis of the pooled data showed that the wet/dry ratio values mainly reflected the amount of intra-alveolar edema (rs = 0.442; p = 0.0057) but only stereological assessment of edema formation revealed differences depending on the treatment used. Only stereological data correlated significantly with oxygen tension measured at the end of reperfusion (rs = –0.530; p = 0.0009). We conclude that gravimetry is of minor functional importance compared to assessment by stereological methods which prove to be a reliable and efficient tool for the evaluation of IR injury in the different experimental settings<br>Dieser Beitrag ist mit Zustimmung des Rechteinhabers aufgrund einer (DFG-geförderten) Allianz- bzw. Nationallizenz frei zugänglich
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Fehrenbach, Antonia, Heinz Fehrenbach, Thorsten Wittwer, Matthias Ochs, Thorsten Wahlers, and Joachim Richter. "Evaluation of Pulmonary Edema: Stereological versus Gravimetrical Analysis." Karger, 2001. https://tud.qucosa.de/id/qucosa%3A27457.
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Assessment of lung edema by gravimetrical analysis is a standard method to evaluate the severity of experimentally induced ischemia/reperfusion (IR) injury. The aim of this study was to compare gravimetrical assessment of pulmonary edema with a stereological approach which allows for qualitative and quantitative distinction between intravascular and edematous fluids by light microscopy. Eight experimental groups which differed in mode of preservation, ischemic storage and pharmacological treatments were studied in an extracorporeal rat lung model. Analysis of the pooled data showed that the wet/dry ratio values mainly reflected the amount of intra-alveolar edema (rs = 0.442; p = 0.0057) but only stereological assessment of edema formation revealed differences depending on the treatment used. Only stereological data correlated significantly with oxygen tension measured at the end of reperfusion (rs = –0.530; p = 0.0009). We conclude that gravimetry is of minor functional importance compared to assessment by stereological methods which prove to be a reliable and efficient tool for the evaluation of IR injury in the different experimental settings.<br>Dieser Beitrag ist mit Zustimmung des Rechteinhabers aufgrund einer (DFG-geförderten) Allianz- bzw. Nationallizenz frei zugänglich.
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Lattach, Youssef. "Development and characterization of sensing layers based on molecularly imprinted conducting polymers for the electrochemical and gravimetrical detection of small organic molecules." Phd thesis, Conservatoire national des arts et metiers - CNAM, 2011. http://tel.archives-ouvertes.fr/tel-00699628.
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In the field of chemical and biological sensors, the increased need for better sensitivity, faster response and higher selectivity during an analysis process, requires the development of more and more efficient transducing sensing layers. In this context, and with the aim to detect small non-electroactive molecules, such as atrazine (ATZ), we designed, characterized and developed sensing layers constituted by functionalized Molecularly Imprinted Conducting Polymers (MICP) and we integrated them into electrochemical and gravimetrical sensors. Starting from acetonitrile pre-polymerization media containing ATZ as template molecules in the presence of thiophene-based functional monomers (FM, namely TMA, TAA, EDOT, TMeOH or Th), differently functionalized and structurally different polythiophene-based FM-MICP films were electrosynthesized onto gold substrates and used for ATZ detection. The sensing properties of FM-MICP layers were shown to result from the presence in their backbones of pre-shaped FM-functionalized imprinted cavities which keep the memory of the targets. Nevertheless, non-specific adsorption onto the surface of the sensing layers takes place systematically, which affects the selectivity of the recognition process. Thanks to surface characterization techniques, we highlighted the influence of the thickness and of the structural properties of the layers on the efficiency of the recognition process. Besides, this latter was shown to operate in the bulk of the polymer matrixes thanks to layers porosity. On another hand, electrochemical measurements correlated with semi-empirical calculations demonstrated the influence of the nature of FM on the strength of the ATZ-FM interaction in the pre-polymerization medium, and then on the number of ATZ molecular imprints and on the sensitivity towards ATZ of the FM-MICP layers. We showed that TAA-MICP, which presents a low limit of detection (10-9 mol L-1) and a large dynamic range (10-8 to 10-4 mol L-1), is the best sensing layer since it offers the best compromise between high level of specific detection of ATZ and low level of non-specific adsorption. Finally, TAA-MICP was used as sensitive layer in an original Electrochemical Surface Acoustic Wave sensor (ESAW) which enabled simultaneous coupled gravimetric and electrochemical measurements.
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Ferreira, Eduardo Rodrigues. "Gestão e gerenciamento dos resíduos de serviços de saúde pela administração pública municipal na UGRHI do Pontal do Paranapanema - SP." Universidade de São Paulo, 2012. http://www.teses.usp.br/teses/disponiveis/18/18138/tde-07062013-090231/.
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Esta tese de doutorado teve como foco principal das análises, as atividades de gestão e gerenciamento dos resíduos de serviços de saúde na Unidade de Gerenciamento de Recursos Hídricos 22, Pontal do Paranapanema - SP. A hipótese formulada foi de que não havia conhecimento técnico em manejo de resíduos de serviços de saúde. Nos municípios, foram analisados a gestão e o gerenciamento dos resíduos de serviços de saúde em 19 municípios bem como as atividades das vigilâncias sanitárias municipais e o gerenciamento interno e externo dos resíduos de serviços de saúde de 77 estabelecimentos geradores, distribuídos nesses municípios, a saber: unidades básicas de saúde, prontos socorros e laboratório de análises clínicas. O estudo abrangeu também as atividades da Companhia Ambiental do Estado de São Paulo e do Comitê de Bacia Hidrográfica. As técnicas empregadas para a realização desta pesquisa foram: coleta de dados (emprego de questionário, formulário e observação); pesquisa bibliográfica (teses, livros, artigos) e documental (leis, normas, contratos, planos municipais de saúde e plano de gerenciamento dos resíduos de serviços de saúde - PGRSS); caracterização gravimétrica e classificação dos resíduos de serviços de saúde gerados pelos estabelecimentos municipais, durante o período de oito dias, como preconiza a Organização Pan-Americana de Saúde, aliada à Resolução CONAMA nº. 358/05. A pesquisa demonstrou que todos os 19 municípios contrataram empresas especializadas, terceirizando a coleta, o transporte, o tratamento e a disposição final dos resíduos de serviços de saúde. Além disso, foram verificadas dificuldades das vigilâncias sanitárias municipais em relação, às atividades de fiscalização, monitoramento e controle de resíduos de serviços de saúde, principalmente devido à transferência da gestão plena às vigilâncias sanitárias municipais pelo governo do Estado de São Paulo. Quanto ao gerenciamento interno dos resíduos de serviços de saúde nos estabelecimentos geradores, constatou-se a dificuldade em segregar resíduos do grupo A (infectantes) dos integrantes do grupo D (comuns), tendo sido constatada uma média de 15% de resíduos considerados comuns junto aos infectantes. A pesquisa revelou ainda, em relação aos procedimentos adotados, um aspecto preocupante do ponto de vista do cumprimento da RDC ANVISA nº 306/04, uma vez que 97,4% dos estabelecimentos não possuíam o PGRSS. A infraestrutura para abrigar os resíduos de serviços de saúde dentro das normas técnicas nos estabelecimentos geradores é quase inexistente, considerando que tal instalação foi verificada em somente 6,49% dos 77 estabelecimentos geradores. Diante dos resultados, confirmou-se, por fim, a ausência de capacitação técnica voltada ao manejo dos resíduos de serviços de saúde, na área de estudo desta pesquisa, corroborando a hipótese inicialmente estabelecida.<br>This thesis had as main focus of the analysis, management activities and management of health care waste at the division of water resources unit 22, Pontal do Paranapanema - SP. The hypothesis was that there was not any technical knowledge about health care waste management. It was analyzed the management and health care waste of 19 municipalities as well as all the activity of sanitary surveillance and the internal and external management of health care waste from 77 generators institutions within these municipalities namely: basic health units, emergency rooms and clinical laboratories. The study also focused on the activities of the Environmental Company of S ão Paulo and Watershed Committee. Among the methodological procedures for the research were used: data collection, bibliographic and documental research, gravimetrical characterization and classification of the waste generated by municipal health facilities, for eight days, based on the Pan American Health Organization together with CONAMA Resolution 358/05.The research found that all counties had hired specialized companies, outsourcing the collection, transportation, treatment and disposal of health care waste. The survey also revealed difficulties in the municipal health surveillance regarding the fiscalization activities, health care waste monitoring and controlling, mainly due to the transition of the full management to municipal health surveillance of the State of Sao Paulo. Regarding internal the health care waste, the survey found that municipalities had difficulties in the procedure for waste segregation between group A and group D, since it was observed approximately 15% of common waste among infectious waste. Regarding the procedures adopted to carry out the internal management of health care waste, the study showed an worrying aspect from the standpoint of compliance with ANVISA RDC 306/04, since 97,4% of the health facilities had no waste management plan. The infrastructure to shelter the health care waste was almost nonexistent, visits to these facilities found the existence in only 6,49% of 77 waste generators. Considering the results, we concluded the absence of technical training focused on waste management of health facilities in the researched area, supporting the hypothesis initially established.
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Tavares, Jimy Carter Lima. "Caracterização dos resíduos sólidos urbanos da cidade de Maceió-AL." Universidade Federal de Alagoas, 2008. http://repositorio.ufal.br/handle/riufal/418.
Full textAbstract:
This work presents and argues the characterization of the urban solid residues generated in
Maceió-AL, by means of laboratory and field assays, searching to contribute for operational
improvements in the system of urban cleanness of the city. The residues had been collected
monthly from routes previously defined, in the period of one year, in eight different quarters,
representing each one of these an administrative region and existing partner-economic
classroom in the city. In the total sixty and nine collections had been carried through, of March
of 2006 the February of 2007. In the field assays, carried through in the landfill of Maceió,
specific weight and gravimetrical composition had been evaluated the parameters; in the
laboratory (LSA) of the Federal University of Alagoas had been carried through the following
parameters physicist-chemistries: pH, solids (fixed, volatile and total) and text of humidity.
The gotten data had demonstrated that the average gravimetrical composition of the solid
residues is of 56,6% of organic substance, to 8.9% of paper/cardboard, 13.5% of plastic, 1.7%
of metals, 1.3% of glasses, wooden 1.5% leather/rubber and 2.6% of rags and 13.8% of lands
and similes. The composition average physicist-chemistry for the organic substance presented
pH equal the 4,8, volatile humidity of 75,0%, solids equal 77.7%, and fixed solids of 22,3%. It
is concluded that the urban solid residues of Maceió present of 56,6% of organic substance,
with potential to be used in the compostagem, and 25,4% of material potentially you recycle,
correspondents the paper/cardboard, plastics, metals and glasses, making possible the public
power to implant a program of selective collection for recycling of these materials.<br>Fundação de Amparo a Pesquisa do Estado de Alagoas<br>Este trabalho apresenta e discute a caracterização dos resíduos sólidos urbanos gerados em
Maceió-AL, por meio de ensaios de campo e de laboratório, buscando contribuir para
melhorias operacionais no sistema de limpeza urbana da cidade. Os resíduos foram coletados
mensalmente a partir de rotas previamente definidas, no período de um ano, em oito bairros
diferentes, representando cada um destes uma região administrativa e classe sócio-econômica
existente no município. No total foram realizadas sessenta e nove coletas, de março de 2006 a
fevereiro de 2007. Nos ensaios de campo, realizados no lixão de Maceió, foram avaliados os
parâmetros peso específico e composição gravimétrica; e no laboratório de Saneamento
Ambiental (LSA) da Universidade Federal de Alagoas foram realizados os seguintes
parâmetros físico-químicos: pH, sólidos (fixos, voláteis e totais) e teor de umidade. Os dados
obtidos demonstraram que a composição gravimétrica média dos resíduos sólidos é de 56,6 %
de matéria orgânica, 8,9% de papel/papelão, 13,5% de plástico, 1,7% de metais, 1,3% de
vidros, 1,5% de madeira/couro/borracha e 2,6% de trapos e 13,8% de terras e similares. A
composição físico-química média para a matéria orgânica apresentou pH igual a 4,8, umidade
75,0%, sólidos voláteis igual a 77,7%, e sólidos fixos de 22,3%. Conclui-se que os resíduos
sólidos urbanos de Maceió apresentam 56,6% de matéria orgânica putrescível, com potencial
para ser utilizada na compostagem, e 25,4% de materiais potencialmente recicláveis,
correspondentes a papel/papelão, plásticos, metais e vidros, possibilitando o poder público
implantar um programa de coleta seletiva para reciclagem desses materiais.
Books on the topic "Gravimetrically"
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Gillette, Marcia L., and Donald F. Clemens. Determining the Formula of an Ionic Hydrate Gravimetrically. Chemical Education Resources, 1996.
Find full textBook chapters on the topic "Gravimetrically"
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Estrella-Guayasamín, Marcelo, Victor Vivar Quiroz, Aaron Delgado Quinto, and Fernando Gomez Berrezueta. "Effect of Oxyhydrogen Gas (HHO) Addition on Fuel Consumption of M2 Category Vehicle by Road Tests." In Lecture Notes in Networks and Systems. Springer Nature Switzerland, 2025. https://doi.org/10.1007/978-3-031-87065-1_21.
Full textAbstract:
Abstract A change in fossil fuel consumption within the automotive sector is crucial due to its significant impact on climate change. This study assessed the effect of electrolyte concentration and HHO flow rate on fuel consumption in an M2 vehicle. A 2023 KARRY Q22L AC 1.2 5P 4X2 TM van, classified as M2, was equipped with a wet cell HHO gas generator powered by a variable DC source. The cell consisted of two 316 stainless steel plates, each 10 cm by 10 cm by 1.5 mm, containing 250 cm³ of electrolyte. The electrolyte was made from 1 liter of distilled water and KOH concentrations ranging from 0.5% to 1.5%. HHO flows of 1.03, 1.31, and 1.69 slpm were achieved with currents of 2, 7, and 17 A, respectively. Fuel consumption was measured gravimetrically during 40 km road tests on the Virgen de Fátima - Puerto Inca route, following the extra-urban driving cycle (EUDC) for low-power vehicles. Fuel consumption reductions of 5–8% were observed with increased HHO flow and higher KOH concentrations.
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Bakker, Karel, Sharyn Ossebaar, Rob Middag, and Matthew P. Humphreys. "Maintaining Inter-Comparability of Nutrient Measurements." In Springer Oceanography. Springer Nature Singapore, 2025. https://doi.org/10.1007/978-981-96-2520-8_4.
Full textAbstract:
Abstract Measurements of marine nutrient concentrations are necessary to investigate global biogeochemical cycles, including in the context of climate change, as nutrients are closely coupled to the carbon cycle. To study these phenomena on a global scale, measurements must be internationally comparable between laboratories and calibrated to a metrologically traceable reference standard. In this chapter, we describe how well-trained chemical analysts following Good Laboratory Practice can meet these requirements. Inter-laboratory comparability is not possible without first achieving consistent and reproducible measurements within a single laboratory. First, the measurement reproducibility must be monitored and kept constant within each session of analysis. Second, this criterion should be maintained from one analysis session to the next, for example by using an internal laboratory reference standard and/or conducting duplicate measurements across different sessions. Third, an internationally accepted Certified Reference Material (CRM) should be used to assess the comparability of the data with other laboratories worldwide. Regular participation in laboratory inter-comparison exercises can also reveal systematic bias, thus helping to improve general data quality. Improving analytical quality involves many aspects, such as calibrating volumetric flasks and pipettes gravimetrically to reduce systematic errors, but also a number of seemingly small procedural improvements that can noticeably improve measurement precision and consistency. Each step in the overall procedure from sampling, calibration and analysis through to data reporting contributes to the precision and accuracy of the results.
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Trisunaryanti, Wega, Karna Wijaya, Desi Suryani, and Uswatul Chasanah. "The Effect of HNO3 and/or NaOH Treatments on Characteristics of Mordenite." In Advances in Geopolymers Synthesis and Characterization [Working Title]. IntechOpen, 2021. http://dx.doi.org/10.5772/intechopen.96444.
Full textAbstract:
Modification of mordenite had been performed by HNO3 and/or NaOH treatments and used as a catalyst in the hydrotreating of pyrolyzed α-cellulose. The Si/Al ratio of mordenites was analyzed by Inductively Coupled Plasma (ICP), the acidity was gravimetrically determined using ammonium vapor adsorption, the crystallinity was identified by X-ray Diffraction (XRD), and pore characters of mordenites (BHM, BAM0.1, and BAM0.5) were analyzed using Gas Sorption Analyzed (GSA). Catalytic activity and selectivity of the mordenites were evaluated in the hydrotreating of pyrolyzed α-cellulose under 20 mL minute−1 H2 gas flow at 450 °C for 2 h with the weight ratio of catalyst:feed was 1:60. The liquid products were analyzed using Gas Chromatography-Mass Spectrometer (GC–MS). The acidity of mordenites decreased along with the increase of Si/Al rasio, except for the AM0.1 mordenite. The average pore diameter of BHM, BAM0.1 and BAM0.5 was 2.96; 3.34 and 4.53 nm, respectively. The BAM0.1 showed the highest catalytic activity in producing liquid fraction (64.04 wt%). The BAM0.5 showed the highest catalytic selectivity towards biofuels, i.e. 1-pentene 0.44 (wt%); 2-heptyne 2.75 (wt%) and 1-propanol 3.05 (wt%) from the hydrotreating process of pyrolyzed α-cellulose.
Conference papers on the topic "Gravimetrically"
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Sotoudeh, Kaveh, and Bo Yang. "On-Line Cleaning of Year-Round Building HVAC Loops." In CORROSION 1999. NACE International, 1999. https://doi.org/10.5006/c1999-99102.
Full textAbstract:
Abstract A cleaning product is discussed which protects metals as it removes rust from corroded surfaces. This bi-functionality and the slow rate of removal makes it a candidate for on-line cleaning of HVAC loops. Two different mechanisms are involved in silt and rust removal. Silt is dispersed, while hydrated rust is dispersed as well as solubilized. Air-dried iron oxide attached to a corroded field pipe did not disperse but was slowly solubilized. Corrosion inhibition afforded by the formulation is studied gravimetrically and by LCM. It showed mild steel protection in presence of the product is not limited to clean surfaces, but is extended to under-deposit corrosion.
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Agrawal, A. K., C. Durr, and G. H. Koch. "Sulfide Films and Corrosion Rates of AISI 1018 Carbon Steel in Saline Solutions in the Presence of H2S and CO2 at Temperatures up to 175° F." In CORROSION 2004. NACE International, 2004. https://doi.org/10.5006/c2004-04383.
Full textAbstract:
Abstract The protective properties of iron sulfide films formed on carbon steel equipment in gas and oil production fields depend upon several environmental factors, such as concentrations of H2S and CO2, salinity, and temperature. A recent article (Paper No. 02223, Corrosion/2002) has reviewed the applicability of various empirical models that are used for estimating corrosion rates of carbon steels in CO2/H2S environments, and has found that each model has limitation in that it is useful only in very specific ranges of the variables from which the model was developed. Therefore, more definitive corrosion rate data, generated from laboratory investigations, are often required to cover the environmental conditions existing in production fields of interest. The present laboratory investigation, which was performed with AISI 1018 carbon steel in 0.01% NaCl and 10% NaCl solutions with 1% CO2 and 0.03% to 3% H2S, at 27° to 79° C (81° to 175° F), covered virtually three decades of CO2/H2S ratio - 0.0, 0.3, 3.3 and 33. Nitrogen was the balance gas in each gas mixture that was continuously refreshed in the test cell at atmospheric pressure. The corrosion rate of the carbon steel specimens was determined gravimetrically and also by the electrochemical impedance spectroscopy (EIS) technique. The sulfide films formed on the specimens were characterized with the low angle X-ray diffraction technique. A strong correlation was found between the corrosion rate and CO2/H2S ratio for each of the two test solutions and the temperatures investigated. However, no systematic effect of temperature was found on the corrosion rate in either of the solutions. In general, the EIS technique yielded corrosion rates that were much higher than that obtained gravimetrically in the same environment. Mackinawite was found to be the predominant species in the iron sulfide films. Only traces of troilite, greigite and pyrite were detected in some of the specimens.
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Schleich, W., R. Feser, G. Schmitt, K. Schnier, T. Gommlich, and S. Günther. "Effect of Seawater Chlorination on the Erosion Corrosion Behavior of Copper-Nickel Alloy CuNi90/10." In CORROSION 2008. NACE International, 2008. https://doi.org/10.5006/c2008-08231.
Full textAbstract:
Abstract The influence of dissolved sodium hypochlorite on the flow resistance of UNS C70600 (CuNi90/10) in artificial ASTM D1141seawater at room temperature was investigated gravimetrically using the rotating cage and the electrochemically controlled submersed jet impingement tests. It appeared that even under unfavorable conditions (as-delivered surface, 5 ppm hypochlorite) the critical wall shear stress for initiation of flow induced localized corrosion (FILC) reached levels of 200 Pa. Six weeks pre-exposure in hypochlorite-free artificial seawater at room temperature yields flow resistant protective scales which resist wall shear stresses up to 370 Pa (even in the presence of 5 ppm hypochlorite) without initiation of FILC. The value of 43 Pa previously reported in the literature for the critical wall shear stress of CuNi90/10 in seawater is obviously much too conservative.
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Vidic, K. J., G. Mori, M. Yasir, and D. Knoll. "NaCl- and CaCl2-Induced High Temperature Corrosion of Automotive Exhaust Components." In CORROSION 2018. NACE International, 2018. https://doi.org/10.5006/c2018-11303.
Full textAbstract:
Abstract The high temperature corrosion behavior of ferritic stainless steel UNS S43940 has been investigated by means of cyclic exposure tests (CETs) at 650°C, in presence of NaCl and CaCl2 containing salt deposits and in test gases with different O2 and H2O concentrations. CETs of steel sheets, coated with a salt layer and steel sheets, covered by a salt-contaminated glass fiber-insulation mat, have been performed. Tested salts were NaCl and CaCl2xH2O in different weight ratios. Steel specimen have been investigated gravimetrically, optically and by means of scanning electron microscopy (SEM) with energy dispersive X-ray spectroscopy (EDX). The oxides have been analyzed via X-ray diffraction (XRD), ion chromatography (IC), flame atomic absorption spectroscopy (FAAS) and UV/VIS spectroscopy. Results show that in presence of NaCl, CaCl2 and oxygen, voluminous Fe2O3- and CaCrO4-containing oxide scales are formed. Highest mass loss was measured on salt-coated steel specimen, exposed to air + 0.05 % H2O. Steel sheets with the salt-contaminated mat showed significantly lower mass loss than those with the salt layer.
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Leeds, Sarah S., and Robert A. Cottis. "The Influence of Cathodically Generated Surface Films on Corrosion and the Currently Accepted Criteria for Cathodic Protection." In CORROSION 2009. NACE International, 2009. https://doi.org/10.5006/c2009-09548.
Full textAbstract:
Abstract Cathodically generated surface films on steel specimens have been discovered to vary in composition and protective nature depending upon the electrolyte composition, pH and applied potential. Three electrolytes were studied, pure 3.5% NaCl, artificial seawater and an alkaline solution of composition similar to that found beneath a disbonded land-based pipeline coating. Specimen Potentials varied from free corrosion to -1400 mV (Ag/AgCl/3.5% NaCl). Films grown as a result of applying Cathodic Protection (CP) were analysed by X-Ray Diffraction and Scanning Electron Microscopy and corrosion rates were determined gravimetrically. Films grown in 3.5% NaCl were composed of iron corrosion products and were found to be more coherent and protective than calcareous deposits grown in artificial seawater. The ratio of magnesium to calcium of specimens exposed to artificial seawater influenced the film protective nature. Films grown in the land-based electrolyte were composed of a mixture of iron corrosion products and calcium carbonate with little magnesium present. Current Criteria for CP used to control land-and sea-based systems will be assessed in view of a better understanding of what happens at the metal /electrolyte interface upon the application of Cathodic Protection.
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Zelinka, Samuel L., and Stan Lebow. "Corrosion of Wires on Wooden Wire-Bound Packaging Crates." In CORROSION 2015. NACE International, 2015. https://doi.org/10.5006/c2015-05617.
Full textAbstract:
Abstract Wire-bound packaging crates are used by the US Army to transport materials. Because these crates may be exposed to harsh environments, they are dip-treated with a wood preservative (biocide treatment). For many years, zinc-naphthenate was the most commonly used preservative for these packaging crates and few corrosion problems with the wires were observed. Recently, copper based alternatives to zinc naphthenate have been used, and corrosion problems have been observed. Here, we present the results of laboratory corrosion testing of 10 different wood treatments to see which preservatives have the potential to cause corrosion problems. The laboratory test was designed to mimic the production process; wires from packaging crates were attached to wood and dipped in the wood preservative and stored in a polyethylene bag for either 2 or 8 weeks to simulate how the crates are stored in the warehouse. The amount of corrosion was examined both visually and gravimetrically. Zinc naphthenate and Preservative A were the least corrosive preservatives, and there were no statistical differences between these two preservatives. The remaining treatments had at least 5 times more corrosion than these two preservatives. Three of the 10 treatments showed a linear increase in the amount of corrosion with time, suggesting that they were still corroding as rapidly at week 8 as they were at week 2 and present a high risk of corrosion. From these results, Preservative A (a copper ethanolamine complex containing citric acid) appears to be the least corrosive alternative to zinc naphthenate.
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Rocchini, Gabriele, and Giorgio Perboni. "Electrochemical Characterization of Some Commercial Inhibitors Used for the Acid Cleaning of Steam Generators." In CORROSION 1986. NACE International, 1986. https://doi.org/10.5006/c1986-86352.
Full textAbstract:
Abstract The behaviour of four commercial inhibitors used for the pickling baths and acid cleaning of steam generators in thermal power stations has been investigated and their inhibitor effectiveness has been determined both with gravimetrical tests and with electrochemical measurements. The latter have shown that a complete surface impedance diagram on Argand's plane is very helpful in discriminating the behaviour of a given corrosion inhibitor, quantitatively as well as qualitatively. In addition, numerical elaboration of the polarization curves has revealed that corrosion current density gives a satisfactory reproduction of the real behaviour of the metal sample only for one commercial inhibitor. Use of the polarization resistance, however, has proved to be a valuable means of evaluating the inhibiting power. Within the concentration interval of practical interest, polarization resistance has yielded the same results as the gravimetric tests. A very interesting observation is that all four products exhibit a constant efficiency over a fairly wide concentration interval. This is of considerable importance because it is our opinion that the concentration of the inhibitor is never homogeneous during acid cleaning.
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Venstrom, Luke J., and Jane H. Davidson. "Rapid Production of Hydrogen and Carbon Monoxide via the Heterogeneous Oxidation of Zn(g)." In ASME 2012 6th International Conference on Energy Sustainability collocated with the ASME 2012 10th International Conference on Fuel Cell Science, Engineering and Technology. American Society of Mechanical Engineers, 2012. http://dx.doi.org/10.1115/es2012-91136.
Full textAbstract:
The heterogeneous oxidation of Zn(g) is considered as an improved approach to the production of H2 and CO in the two-step Zn/ZnO solar thermochemical cycle. The rate of Zn(g) oxidation by H2O and CO2 is measured gravimetrically in a quartz tubular flow reactor for temperatures between 800 and 1150 K, Zn(g) concentrations up to 36 mol%, and H2O/CO2 concentrations up to 45 mol%. The rate of the heterogeneous oxidation of Zn(g) by both H2O and CO2 is on the order of 10−8–10−5 mol cm−2 s−1. For similar oxidizing conditions, H2O oxidizes Zn(g) three times as fast as CO2, indicative of a lower heterogeneous oxidation activation energy in the H2O system. Less than one second is required to convert more than 85% of Zn to ZnO for all temperatures in both the H2O and CO2 reacting systems.
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Schwenke, T., C. Rieker, and M. A. Wimmer. "Load Scenarios Influence Fluid Absorption of Polyethylene." In World Tribology Congress III. ASMEDC, 2005. http://dx.doi.org/10.1115/wtc2005-63578.
Full textAbstract:
Wear of total joint replacements is determined gravimetrically in simulator studies. A mix of bovine serum, distilled water, and additives is intended to replicate the lubrication conditions in-vivo. Weight gain due to fluid absorption during testing of UHMWPE components is corrected using a load soak station. In this study six sets of UHMWPE pins were tested for their fluid soak behavior. The samples were subjected to three different loading scenarios while being submersed in two types of commonly used lubricants. After two million cycles or 23.1 days, respectively, the different fluids lead to significantly different soaking results. Test groups that were dynamically loaded gained more weight than unloaded or statically loaded samples. The results suggest that dynamically loaded soak control stations are required during wear testing of UHMWPE components. Otherwise the fluid uptake masks the wear measurement, especially for new polyethylene materials with low wear rates. Furthermore, an agreement on detailed lubricant specifications is desirable.
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Gauffreau, Andrew M., and Keunhan Park. "Femtogram-Level Thermophysical Property Measurement of Polymeric Samples Using Heated Microcantilevers." In ASME/JSME 2011 8th Thermal Engineering Joint Conference. ASMEDC, 2011. http://dx.doi.org/10.1115/ajtec2011-44489.
Full textAbstract:
This article investigates thermophysical property measurement of femtogram-level polymeric samples by using the 3ω method on a heated microcantilever probe. A localized thermal scooping method was employed to acquire 449 fg of polyethylene terephthalate (PET) sample, measured gravimetrically, directly onto the heater of the cantilever. It is shown that the sample case has a 3ω signal that is smaller in magnitude than the bare case, suggesting that sample properties could be determined using the processes discussed here. A finite element analysis (FEA) model was also developed to compute the steady periodic behavior of the cantilever in the frequency domain. In order to drastically reduce the computational cost and consider the transient effect of the surrounding air, the FEA model implements the complex thermal conductance of the air as the boundary condition rather than modeling the air as a separate domain. The comparison of the modified model with the model that includes the air in the system reveals that the running time has improved by one order of magnitude while showing excellent agreement. The obtained results will expand the characterization and functionality of microcantilevers leading to advancements in localized thermal analysis.
Reports on the topic "Gravimetrically"
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George, D. L., and R. C. Burkey. PR-015-06603-R01 Tests of Instruments for Measuring Hydrocarbon Dew Points in Natural Gas Streams Phase 1. Pipeline Research Council International, Inc. (PRCI), 2008. http://dx.doi.org/10.55274/r0010820.
Full textAbstract:
Two commercially-available hydrocarbon dew point analyzers, an Ametek� Model 241 CE II and a Michell Condumax II, were provided by JIP participants for testing. An experimental HCDP research apparatus, first designed at Southwest Research Institute to gather reference hydrocarbon dew point data, was modified to test the automated analyzers. Both automated analyzers, along with a Bureau of Mines chilled mirror device serving as a reference, were installed in the apparatus. Gravimetrically-prepared gas blends containing hydrocarbons through decane were used as test gases, and a small warm box was built to keep the test gases above their hydrocarbon dew points at various simulated line pressures.
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George and Hart. PR-015-06603-R02 Tests of Instruments for Measuring Hydrocarbon Dew Points in Natural Gas Streams Phase 2. Pipeline Research Council International, Inc. (PRCI), 2008. http://dx.doi.org/10.55274/r0010969.
Full textAbstract:
Research has assessed the accuracy of two commercially-available hydrocarbon dew point (HCDP) analyzers, an Ametek� Model 241 CE II and a Michell Condumax II. During a previous phase of this project, both automated analyzers, along with a Bureau of Mines chilled mirror device serving as a reference, were tested on gravimetrically-prepared gas blends chosen to simulate a transmission-quality gas and a production gas. The measurement repeatability of both units was found to be better than the manual chilled mirror. Trends in the analyzer and manual chilled mirror measurements suggested that differences in performance between the automated units were related to their measurement techniques and default set points. During the second phase of the project, the Ametek and Michell automated analyzers were tested again on the transmission-quality test gas used in Phase 1, but with specific levels of contamination added to gain knowledge of their performance under adverse conditions. In one round of tests, water vapor was added to simulate a transmission gas with water vapor levels above common tariff specifications. In the second round of tests, the test gas contained both methanol and water vapor, simulating a stream to which methanol has been added to prevent hydrates. Contaminants were added to the test gas stream in amounts such that, depending upon the pressure of the test stream, the contaminant dew point would be reached first, the HCDP would be reached first, or the two phases would condense simultaneously. Multiple HCDP measurements were made with the analyzers to determine their ability to accurately measure HCDPs under these adverse conditions. Analyzer results were again compared to HCDP measurements taken with the Bureau of Mines chilled mirror device and a digital video camera. Results were adjusted for small changes in the heavy hydrocarbon content of the test gases over time, using predictions from an equation of state and gas chromatographic analyses of the test gases.
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Rapid Integrated Method for Total Dietary Fiber. Cereal & Grains Association, 2021. http://dx.doi.org/10.1094/aaccintmethod-32-60.01.
Full textAbstract:
This method determines total dietary fiber (TDF) in foods and food ingredients, as defined by Codex Alimentarius. The method measures soluble and insoluble dietary fiber, including resistant starch, as well as nondigestible oligosaccharides. In this method, enzymatic digestion is used to simulate human intestinal digestion. Insoluble dietary fiber (IDF) and soluble dietary fiber that precipitates in 78% ethanol (SDFP) are separated by filtration and quantified gravimetrically. Additionally, highly soluble oligosaccharides (SDFS) are quantified by chromatographic separation. TDF is reported as the sum of the gravimetric and high-performance liquid chromatography (HPLC) results. The digestion and chromatographic conditions of this method have been modified from those of AACC Approved Methods 32-45.01 and 32-50.01 in an attempt to better simulate human digestion and to allow for more exact quantitation.