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Sample records for underway chromatographic system

  1. Dual liquid and gas chromatograph system

    Science.gov (United States)

    Gay, D.D.

    A chromatographic system is described that utilizes one detection system for gas chromatographic and micro-liquid chromatographic determinations. The detection system is a direct-current, atmospheric-pressure, helium plasma emission spectrometer. The detector utilizes a nontransparent plasma source unit which contains the plasma region and two side-arms which receive effluents from the micro-liquid chromatograph and the gas chromatograph. The dual nature of this chromatographic system offers: (1) extreme flexibility in the samples to be examined; (2) extreme low sensitivity; (3) element selectivity; (4) long-term stability; (5) direct correlation of data from the liquid and gas samples; (6) simpler operation than with individual liquid and gas chromatographs, each with different detection systems; and (7) cheaper than a commercial liquid chromatograph and a gas chromatograph.

  2. Modeling Aquatic Toxicity through Chromatographic Systems.

    Science.gov (United States)

    Fernández-Pumarega, Alejandro; Amézqueta, Susana; Farré, Sandra; Muñoz-Pascual, Laura; Abraham, Michael H; Fuguet, Elisabet; Rosés, Martí

    2017-08-01

    Environmental risk assessment requires information about the toxicity of the growing number of chemical products coming from different origins that can contaminate water and become toxicants to aquatic species or other living beings via the trophic chain. Direct toxicity measurements using sensitive aquatic species can be carried out but they may become expensive and ethically questionable. Literature refers to the use of chromatographic measurements that correlate to the toxic effect of a compound over a specific aquatic species as an alternative to get toxicity information. In this work, we have studied the similarity in the response of the toxicity to different species and we have selected eight representative aquatic species (including tadpoles, fish, water fleas, protozoan, and bacteria) with known nonspecific toxicity to chemical substances. Next, we have selected four chromatographic systems offering good perspectives for surrogation of the eight selected aquatic systems, and thus prediction of toxicity from the chromatographic measurement. Then toxicity has been correlated to the chromatographic retention factor. Satisfactory correlation results have been obtained to emulate toxicity in five of the selected aquatic species through some of the chromatographic systems. Other aquatic species with similar characteristics to these five representative ones could also be emulated by using the same chromatographic systems. The final aim of this study is to model chemical products toxicity to aquatic species by means of chromatographic systems to reduce in vivo testing.

  3. Effect of chromatographic separation on ASP system interface tension and the countermeasures

    Directory of Open Access Journals (Sweden)

    Jiawei REN

    2016-06-01

    Full Text Available Because of the existing chromatographic separation phenomenon, ASP flooding changes original nature of the system. Therefore, in laboratory ultra-low interfacial tension ASP system is preferred for sand packs flow experiment to research on the effect of chromatographic separation on ASP system interface tension. The two parameters of "breakthrough time" and "output difference" are used to describe the degree of chromatographic separation, and the produced fluid interfacial tensions at the outlet end at 120 min is measured. The research shows that there exists chromatographic separation between three chemicals of ASP system, with first polymer breakthrough and finally surfactant breakthrough; there is most serious chromatographic separation between surfactant and polymer, while minimum chromatographic separation between alkali and polymer; chromatographic separation makes ASP interfacial tension increase from 10-3 magnitude to 10-2 magnitude, affecting flooding effect of ASP system. Thus, reducing the loss of surfactant in the formation will be the main measure to reduce the degree of chromatographic separation. Using sophorolipid as sacrificial agent to replace part of the surfactant injected into formation before ASP system can effectively reduce the impact of chromatography separation and more effectively improve the ultimate recovery ratio.

  4. Performance of chromatographic systems to model soil-water sorption.

    Science.gov (United States)

    Hidalgo-Rodríguez, Marta; Fuguet, Elisabet; Ràfols, Clara; Rosés, Martí

    2012-08-24

    A systematic approach for evaluating the goodness of chromatographic systems to model the sorption of neutral organic compounds by soil from water is presented in this work. It is based on the examination of the three sources of error that determine the overall variance obtained when soil-water partition coefficients are correlated against chromatographic retention factors: the variance of the soil-water sorption data, the variance of the chromatographic data, and the variance attributed to the dissimilarity between the two systems. These contributions of variance are easily predicted through the characterization of the systems by the solvation parameter model. According to this method, several chromatographic systems besides the reference octanol-water partition system have been selected to test their performance in the emulation of soil-water sorption. The results from the experimental correlations agree with the predicted variances. The high-performance liquid chromatography system based on an immobilized artificial membrane and the micellar electrokinetic chromatography systems of sodium dodecylsulfate and sodium taurocholate provide the most precise correlation models. They have shown to predict well soil-water sorption coefficients of several tested herbicides. Octanol-water partitions and high-performance liquid chromatography measurements using C18 columns are less suited for the estimation of soil-water partition coefficients. Copyright © 2012 Elsevier B.V. All rights reserved.

  5. Temperature Control of Gas Chromatograph Based on Switched Delayed System Techniques

    Directory of Open Access Journals (Sweden)

    Xiao-Liang Wang

    2014-01-01

    Full Text Available We address the temperature control problem of the gas chromatograph. We model the temperature control system of the gas chromatograph into a switched delayed system and analyze the stability by common Lyapunov functional technique. The PI controller parameters can be given based on the proposed linear matrix inequalities (LMIs condition and the designed controller can make the temperature of gas chromatograph track the reference signal asymptotically. An experiment is given to illustrate the effectiveness of the stability criterion.

  6. Chromatographic generator systems for the actinides and natural decay series elements

    International Nuclear Information System (INIS)

    McAlister, D.R.; Horwitz, E.P.

    2011-01-01

    This work describes chromatographic radionuclide generator systems for the production of actinides and natural decay series elements. The generator systems begin with alpha emitting parent radioisotopes with half-lives (T 1/2 ) of greater than one year and produce alpha or beta emitting radioisotopes with half-lives of hours to days. Chromatographic systems were chosen to minimize radiolytic damage to chromatographic supports, preserve the parent activity for repeated use, provide high purity daughter radionuclide tracers, and to minimize or eliminate the need for evaporation of solutions of the parent or daughter nuclides. Useful secondary separations involving the daughters of the initial parent radionuclide are also described. Separation systems for 210 Bi, 210 Po, 211 Pb, 212 Pb, 223 Ra, 224 Ra, 225 Ra, 225 Ac, 227 Th, 228 Th, 231 Th, 234 Th, and 239 Np are outlined in detail. (orig.)

  7. A Gas Chromatographic System for the Detection of Ethylene Gas Using Ambient Air as a Carrier Gas.

    Science.gov (United States)

    Zaidi, Nayyer Abbas; Tahir, Muhammad Waseem; Vellekoop, Michael J; Lang, Walter

    2017-10-07

    Ethylene gas is a naturally occurring gas that has an influence on the shelf life of fruit during their transportation in cargo ships. An unintentional exposure of ethylene gas during transportation results in a loss of fruit. A gas chromatographic system is presented here for the detection of ethylene gas. The gas chromatographic system was assembled using a preconcentrator, a printed 3D printed gas chromatographic column, a humidity sensor, solenoid valves, and an electrochemical ethylene gas sensor. Ambient air was used as a carrier gas in the gas chromatographic system. The flow rate was fixed to 10 sccm. It was generated through a mini-pump connected in series with a mass flow controller. The metal oxide gas sensor is discussed with its limitation in ambient air. The results show the chromatogram obtained from metal oxide gas sensor has low stability, drifts, and has uncertain peaks, while the chromatogram from the electrochemical sensor is stable and precise. Furthermore, ethylene gas measurements at higher ppb concentration and at lower ppb concentration were demonstrated with the electrochemical ethylene gas sensor. The system separates ethylene gas and humidity. The chromatograms obtained from the system are stable, and the results are 1.2% repeatable in five similar measurements. The statistical calculation of the gas chromatographic system shows that a concentration of 2.3 ppb of ethylene gas can be detected through this system.

  8. Evaluation of the suitability of chromatographic systems to predict human skin permeation of neutral compounds.

    Science.gov (United States)

    Hidalgo-Rodríguez, Marta; Soriano-Meseguer, Sara; Fuguet, Elisabet; Ràfols, Clara; Rosés, Martí

    2013-12-18

    Several chromatographic systems (three systems of high-performance liquid chromatography and two micellar electrokinetic chromatography systems) besides the reference octanol-water partition system are evaluated by a systematic procedure previously proposed in order to know their ability to model human skin permeation. The precision achieved when skin-water permeability coefficients are correlated against chromatographic retention factors is predicted within the framework of the solvation parameter model. It consists in estimating the contribution of error due to the biological and chromatographic data, as well as the error coming from the dissimilarity between the human skin permeation and the chromatographic systems. Both predictions and experimental tests show that all correlations are greatly affected by the considerable uncertainty of the skin permeability data and the error associated to the dissimilarity between the systems. Correlations with much better predictive abilities are achieved when the volume of the solute is used as additional variable, which illustrates the main roles of both lipophilicity and size of the solute to penetrate through the skin. In this way, the considered systems are able to give precise estimations of human skin permeability coefficients. In particular, the HPLC systems with common C18 columns provide the best performances in emulating the permeation of neutral compounds from aqueous solution through the human skin. As a result, a methodology based on easy, fast, and economical HPLC measurements in a common C18 column has been developed. After a validation based on training and test sets, the method has been applied with good results to the estimation of skin permeation of several hormones and pesticides. Copyright © 2013 Elsevier B.V. All rights reserved.

  9. Acquisition of an Underway CTD System for the Flow Encountering Abrupt Topography DRI

    Science.gov (United States)

    2015-09-30

    Acquisition of an Underway CTD System for the Flow Encountering Abrupt Topography DRI T. M. Shaun Johnston Scripps Institution of Oceanography...westward flow in the North Equatorial Current (NEC) encounters tall, steep, submarine topography and islands. During the Flow Encountering Abrupt... Topography (FLEAT) DRI, investigators will determine: • Whether appreciable energy/momentum is lost from the large-scale NEC flow to smaller scales and

  10. Automated chromatographic laccase-mediator-system activity assay.

    Science.gov (United States)

    Anders, Nico; Schelden, Maximilian; Roth, Simon; Spiess, Antje C

    2017-08-01

    To study the interaction of laccases, mediators, and substrates in laccase-mediator systems (LMS), an on-line measurement was developed using high performance anion exchange chromatography equipped with a CarboPac™ PA 100 column coupled to pulsed amperometric detection (HPAEC-PAD). The developed method was optimized for overall chromatographic run time (45 to 120 min) and automated sample drawing. As an example, the Trametes versicolor laccase induced oxidation of 1-(3,4-dimethoxyphenyl)-2-(2-methoxyphenoxy)-1,3-dihydroxypropane (adlerol) using 1-hydroxybenzotriazole (HBT) as mediator was measured and analyzed on-line. Since the Au electrode of the PAD detects only hydroxyl group containing substances with a limit of detection being in the milligram/liter range, not all products are measureable. Therefore, this method was applied for the quantification of adlerol, and-based on adlerol conversion-for the quantification of the LMS activity at a specific T. versicolor laccase/HBT ratio. The automated chromatographic activity assay allowed for a defined reaction start of all laccase-mediator-system reactions mixtures, and the LMS reaction progress was automatically monitored for 48 h. The automatization enabled an integrated monitoring overnight and over-weekend and minimized all manual errors such as pipetting of solutions accordingly. The activity of the LMS based on adlerol consumption was determined to 0.47 U/mg protein for a laccase/mediator ratio of 1.75 U laccase/g HBT. In the future, the automated method will allow for a fast screening of combinations of laccases, mediators, and substrates which are efficient for lignin modification. In particular, it allows for a fast and easy quantification of the oxidizing activity of an LMS on a lignin-related substrate which is not covered by typical colorimetric laccase assays. ᅟ.

  11. Research Ship Oceanus Underway Meteorological Data, Quality Controlled

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Research Ship Oceanus Underway Meteorological Data (delayed ~10 days for quality control) are from the Shipboard Automated Meteorological and Oceanographic System...

  12. Research Ship Melville Underway Meteorological Data, Quality Controlled

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Research Ship Melville Underway Meteorological Data (delayed ~10 days for quality control) are from the Shipboard Automated Meteorological and Oceanographic System...

  13. Research Ship Healy Underway Meteorological Data, Quality Controlled

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Research Ship Healy Underway Meteorological Data (delayed ~10 days for quality control) are from the Shipboard Automated Meteorological and Oceanographic System...

  14. Research Ship Knorr Underway Meteorological Data, Quality Controlled

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Research Ship Knorr Underway Meteorological Data (delayed ~10 days for quality control) are from the Shipboard Automated Meteorological and Oceanographic System...

  15. Research Ship Atlantis Underway Meteorological Data, Quality Controlled

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Research Ship Atlantis Underway Meteorological Data (delayed ~10 days for quality control) are from the Shipboard Automated Meteorological and Oceanographic System...

  16. NOAA Ship Fairweather Underway Meteorological Data, Quality Controlled

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NOAA Ship Fairweather Underway Meteorological Data (delayed ~10 days for quality control) are from the Shipboard Automated Meteorological and Oceanographic System...

  17. NOAA Ship Rainier Underway Meteorological Data, Quality Controlled

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NOAA Ship Rainier Underway Meteorological Data (delayed ~10 days for quality control) are from the Shipboard Automated Meteorological and Oceanographic System...

  18. Research Ship Tangaroa Underway Meteorological Data, Quality Controlled

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Research Ship Tangaroa Underway Meteorological Data (delayed ~10 days for quality control) are from the Shipboard Automated Meteorological and Oceanographic System...

  19. NOAA Ship Pisces Underway Meteorological Data, Quality Controlled

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NOAA Ship Pisces Underway Meteorological Data (delayed ~10 days for quality control) are from the Shipboard Automated Meteorological and Oceanographic System (SAMOS)...

  20. Standard Format for Chromatographic-polarimetric System small samples assessment

    International Nuclear Information System (INIS)

    Naranjo, S.; Fajer, V.; Fonfria, C.; Patinno, R.

    2012-01-01

    The treatment of samples containing optically active substances to be evaluated as part of quality control of raw material entering industrial process, and also during the modifications exerted on it to obtain the desired final composition is still and unsolved problem for many industries. That is the case of sugarcane industry. Sometimes the troubles implied are enlarged because samples to be evaluated are not bigger than one milliliter. Reduction of gel beds in G-10 and G-50 chromatographic columns having an inner diameter of 16 mm, instead of 25, and bed heights adjustable to requirements by means of sliding stoppers to increase analytical power were evaluated with glucose and sucrose standards in concentrations from 1 to 10 g/dL, using aliquots of 1 ml without undesirable dilutions that could affect either detection or chromatographic profile. Assays with seaweed extracts gave good results that are shown. It is established the advantage to know concentration of a separated substance by the height of its peak and the savings in time and reagents resulting . Sample expanded uncertainty in both systems is compared. It is also presented several programs for data acquisition, storing and processing. (Author)

  1. NOAA Ship Rainier Underway Meteorological Data, Near Real Time

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NOAA Ship Rainier Underway Meteorological Data (Near Real Time, updated daily) are from the Shipboard Automated Meteorological and Oceanographic System (SAMOS)...

  2. NOAA Ship Pisces Underway Meteorological Data, Near Real Time

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NOAA Ship Pisces Underway Meteorological Data (Near Real Time, updated daily) are from the Shipboard Automated Meteorological and Oceanographic System (SAMOS)...

  3. NOAA Ship Fairweather Underway Meteorological Data, Near Real Time

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NOAA Ship Fairweather Underway Meteorological Data (Near Real Time, updated daily) are from the Shipboard Automated Meteorological and Oceanographic System (SAMOS)...

  4. NOAA Ship Delaware II Underway Meteorological Data, Quality Controlled

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NOAA Ship Delaware II Underway Meteorological Data (delayed ~10 days for quality control) are from the Shipboard Automated Meteorological and Oceanographic System...

  5. NOAA Ship Hi'ialakai Underway Meteorological Data, Quality Controlled

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NOAA Ship Hi'ialakai Underway Meteorological Data (delayed ~10 days for quality control) are from the Shipboard Automated Meteorological and Oceanographic System...

  6. NOAA Ship Ronald Brown Underway Meteorological Data, Quality Controlled

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NOAA Ship Ronald Brown Underway Meteorological Data (delayed ~10 days for quality control) are from the Shipboard Automated Meteorological and Oceanographic System...

  7. NOAA Ship Miller Freeman Underway Meteorological Data, Quality Controlled

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NOAA Ship Miller Freeman Underway Meteorological Data (delayed ~10 days for quality control) are from the Shipboard Automated Meteorological and Oceanographic System...

  8. NOAA Ship Oscar Dyson Underway Meteorological Data, Quality Controlled

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NOAA Ship Oscar Dyson Underway Meteorological Data (delayed ~10 days for quality control) are from the Shipboard Automated Meteorological and Oceanographic System...

  9. Research Ship Kilo Moana Underway Meteorological Data, Quality Controlled

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Research Ship Kilo Moana Underway Meteorological Data (delayed ~10 days for quality control) are from the Shipboard Automated Meteorological and Oceanographic System...

  10. NOAA Ship Nancy Foster Underway Meteorological Data, Quality Controlled

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NOAA Ship Nancy Foster Underway Meteorological Data (delayed ~10 days for quality control) are from the Shipboard Automated Meteorological and Oceanographic System...

  11. NOAA Ship Gordon Gunter Underway Meteorological Data, Quality Controlled

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NOAA Ship Gordon Gunter Underway Meteorological Data (delayed ~10 days for quality control) are from the Shipboard Automated Meteorological and Oceanographic System...

  12. NOAA Ship Ka'imimoana Underway Meteorological Data, Quality Controlled

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NOAA Ship Ka'imimoana Underway Meteorological Data (delayed ~10 days for quality control) are from the Shipboard Automated Meteorological and Oceanographic System...

  13. NOAA Ship Oregon II Underway Meteorological Data, Quality Controlled

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NOAA Ship Oregon II Underway Meteorological Data (delayed ~10 days for quality control) are from the Shipboard Automated Meteorological and Oceanographic System...

  14. Chemometric strategy for automatic chromatographic peak detection and background drift correction in chromatographic data.

    Science.gov (United States)

    Yu, Yong-Jie; Xia, Qiao-Ling; Wang, Sheng; Wang, Bing; Xie, Fu-Wei; Zhang, Xiao-Bing; Ma, Yun-Ming; Wu, Hai-Long

    2014-09-12

    Peak detection and background drift correction (BDC) are the key stages in using chemometric methods to analyze chromatographic fingerprints of complex samples. This study developed a novel chemometric strategy for simultaneous automatic chromatographic peak detection and BDC. A robust statistical method was used for intelligent estimation of instrumental noise level coupled with first-order derivative of chromatographic signal to automatically extract chromatographic peaks in the data. A local curve-fitting strategy was then employed for BDC. Simulated and real liquid chromatographic data were designed with various kinds of background drift and degree of overlapped chromatographic peaks to verify the performance of the proposed strategy. The underlying chromatographic peaks can be automatically detected and reasonably integrated by this strategy. Meanwhile, chromatograms with BDC can be precisely obtained. The proposed method was used to analyze a complex gas chromatography dataset that monitored quality changes in plant extracts during storage procedure. Copyright © 2014 Elsevier B.V. All rights reserved.

  15. Development of new process network for gas chromatograph and analyzers connected with SCADA system and Digital Control Computers at Cernavoda NPP Unit 1

    International Nuclear Information System (INIS)

    Deneanu, Cornel; Popa Nemoiu, Dragos; Nica, Dana; Bucur, Cosmin

    2007-01-01

    The continuous monitoring of gas mixture concentrations (deuterium/ hydrogen/oxygen/nitrogen) accumulated in 'Moderator Cover Gas', 'Liquid Control Zone' and 'Heat Transport D 2 O Storage Tank Cover Gas', as well as the continuous monitoring of Heavy Water into Light Water concentration in 'Boilers Steam', 'Boilers Blown Down', 'Moderator heat exchangers', and 'Recirculated Water System', sensing any leaks of Cernavoda NPP U1 led to requirement of developing a new process network for gas chromatograph and analyzers connected to the SCADA system and Digital Control Computers of Cernavoda NPP Unit 1. In 2005 it was designed and implemented the process network for gas chromatograph which connected the gas chromatograph equipment to the SCADA system and Digital Control Computers of the Cernavoda NPP Unit 1. Later this process network for gas chromatograph has been extended to connect the AE13 and AE14 Fourier Transform Infrared (FTIR) analyzers with either. The Gas Chromatograph equipment measures with best accuracy the mixture gases (deuterium/ hydrogen/oxygen/nitrogen) concentration. The Fourier Transform Infrared (FTIR) AE13 and AE14 Analyzers measure the Heavy Water into Light Water concentration in Boilers Steam, Boilers BlownDown, Moderator heat exchangers, and Recirculated Water System, monitoring and signaling any leaks. The Gas Chromatograph equipment and Fourier Transform Infrared (FTIR) AE13 and AE14 Analyzers use the new OPC (Object Link Embedded for Process Control) technologies available in ABB's VistaNet network for interoperability with automation equipment. This new process network has interconnected the ABB chromatograph and Fourier Transform Infrared analyzers with plant Digital Control Computers using new technology. The result was an increased reliability and capability for inspection and improved system safety

  16. Large scale gas chromatographic demonstration system for hydrogen isotope separation

    International Nuclear Information System (INIS)

    Cheh, C.H.

    1988-01-01

    A large scale demonstration system was designed for a throughput of 3 mol/day equimolar mixture of H,D, and T. The demonstration system was assembled and an experimental program carried out. This project was funded by Kernforschungszentrum Karlsruhe, Canadian Fusion Fuel Technology Projects and Ontario Hydro Research Division. Several major design innovations were successfully implemented in the demonstration system and are discussed in detail. Many experiments were carried out in the demonstration system to study the performance of the system to separate hydrogen isotopes at high throughput. Various temperature programming schemes were tested, heart-cutting operation was evaluated, and very large (up to 138 NL/injection) samples were separated in the system. The results of the experiments showed that the specially designed column performed well as a chromatographic column and good separation could be achieved even when a 138 NL sample was injected

  17. NOAA Ship Okeanos Explorer Underway Meteorological Data, Near Real Time

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NOAA Ship Okeanos Explorer Underway Meteorological Data (Near Real Time, updated daily) are from the Shipboard Automated Meteorological and Oceanographic System...

  18. NOAA Ship Nancy Foster Underway Meteorological Data, Near Real Time

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NOAA Ship Nancy Foster Underway Meteorological Data (Near Real Time, updated daily) are from the Shipboard Automated Meteorological and Oceanographic System (SAMOS)...

  19. NOAA Ship Ka'imimoana Underway Meteorological Data, Near Real Time

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NOAA Ship Ka'imimoana Underway Meteorological Data (Near Real Time, updated daily) are from the Shipboard Automated Meteorological and Oceanographic System (SAMOS)...

  20. NOAA Ship Gordon Gunter Underway Meteorological Data, Near Real Time

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NOAA Ship Gordon Gunter Underway Meteorological Data (Near Real Time, updated daily) are from the Shipboard Automated Meteorological and Oceanographic System (SAMOS)...

  1. NOAA Ship Oregon II Underway Meteorological Data, Near Real Time

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NOAA Ship Oregon II Underway Meteorological Data (Near Real Time, updated daily) are from the Shipboard Automated Meteorological and Oceanographic System (SAMOS)...

  2. NOAA Ship Hi'ialakai Underway Meteorological Data, Near Real Time

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NOAA Ship Hi'ialakai Underway Meteorological Data (Near Real Time, updated daily) are from the Shipboard Automated Meteorological and Oceanographic System (SAMOS)...

  3. NOAA Ship Ronald Brown Underway Meteorological Data, Near Real Time

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NOAA Ship Ronald Brown Underway Meteorological Data (Near Real Time, updated daily) are from the Shipboard Automated Meteorological and Oceanographic System (SAMOS)...

  4. NOAA Ship Oscar Dyson Underway Meteorological Data, Near Real Time

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NOAA Ship Oscar Dyson Underway Meteorological Data (Near Real Time, updated daily) are from the Shipboard Automated Meteorological and Oceanographic System (SAMOS)...

  5. NOAA Ship McArthurII Underway Meteorological Data, Quality Controlled

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NOAA Ship McArthur II Underway Meteorological Data (delayed ~10 days for quality control) are from the Shipboard Automated Meteorological and Oceanographic System...

  6. [Research on the application of grey system theory in the pattern recognition for chromatographic fingerprints of traditional Chinese medicine].

    Science.gov (United States)

    Wei, Hang; Lin, Li; Zhang, Yuan; Wang, Lianjing; Chen, Qinqun

    2013-02-01

    A model based on grey system theory was proposed for pattern recognition in chromatographic fingerprints (CF) of traditional Chinese medicine (TCM). The grey relational grade among the data series of each testing CF and the ideal CF was obtained by entropy and norm respectively, then the principle of "maximal matching degree" was introduced to make judgments, so as to achieve the purpose of variety identification and quality evaluation. A satisfactory result in the high performance liquid chromatographic (HPLC) analysis of 56 batches of different varieties of Exocarpium Citrus Grandis was achieved with this model. The errors in the chromatographic fingerprint analysis caused by traditional similarity method or grey correlation method were overcome, as the samples of Citrus grandis 'Tomentosa' and Citrus grandis (L.) Osbeck were correctly distinguished in the experiment. Furthermore in the study on the variety identification of Citrus grandis 'Tomentosa', the recognition rates were up to 92.85%, although the types and the contents of the chemical compositions of the samples were very close. At the same time, the model had the merits of low computation complexity and easy operation by computer programming. The research indicated that the grey system theory has good applicability to pattern recognition in the chromatographic fingerprints of TCM.

  7. Evaluation of pesticide adsorption in gas chromatographic injector and column

    Directory of Open Access Journals (Sweden)

    Gevany Paulino de Pinho

    2012-01-01

    Full Text Available Components in complex matrices can cause variations in chromatographic response during analysis of pesticides by gas chromatography. These variations are related to the competition between analytes and matrix components for adsorption sites in the chromatographic system. The capacity of the pesticides chlorpyrifos and deltamethrin to be adsorbed in the injector and chromatographic column was evaluated by constructing three isotherms and changing the column heating rate to 10 and 30 ºC min-1. By using ANCOVA to compare the slope of calibration graphs, results showed that the higher the injector temperature (310 ºC the lower the pesticide adsorption. Also, deltamethrin influenced the adsorption of chlorpyrifos on the column chromatographic.

  8. NOAA Ship Bell M. Shimada Underway Meteorological Data, Near Real Time

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NOAA Ship Bell M. Shimada Underway Meteorological Data (Near Real Time, updated daily) are from the Shipboard Automated Meteorological and Oceanographic System...

  9. NOAA Ship Henry B. Bigelow Underway Meteorological Data, Near Real Time

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NOAA Ship Henry B. Bigelow Underway Meteorological Data (Near Real Time, updated daily) are from the Shipboard Automated Meteorological and Oceanographic System...

  10. NOAA Ship Oscar Elton Sette Underway Meteorological Data, Near Real Time

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NOAA Ship Oscar Elton Sette Underway Meteorological Data (Near Real Time, updated daily) are from the Shipboard Automated Meteorological and Oceanographic System...

  11. The gas-chromatographic and gas-chromatographic-mass-spectrometric identification of halogen-containing organic compounds

    Science.gov (United States)

    Gidaspov, B. V.; Zenkevich, I. G.; Rodin, A. A.

    1989-09-01

    The problem of identifying halogen-containing organic compounds in their gas-chromatographic and gas-chromatographic-mass-spectrometric (GC-MS) determination in different materials has been examined. Particular attention has been paid not to the complete characterisation of methods for carrying out this analysis but to the most important problem of increasing the selectivity at the stages of sampling, separation, and interpretation of the gas-chromatographic and GC-MS information. The bibliography contains 292 references.

  12. Connectivity for underway Coast Guard patrol boats

    OpenAIRE

    Busch, Gregory C.

    1997-01-01

    Approved for public release; distribution is unlimited This thesis examines the US Coast Guard patrol boat's ability to effectively exchange operational data while underway. The patrol boat is currently unable to obtain tactical law enforcement information from the central Law Enforcement Information System 2 (LEIS 2) database while on patrol. LEIS 2 provides access to law enforcement information from Coast Guard, FBI, and state and local law enforcement agencies. Availability of this info...

  13. Alternative chromatographic system for the quality control of lipophilic technetium-99m radiopharmaceuticals such as [99mTc(MIBI6]+

    Directory of Open Access Journals (Sweden)

    D.P. Faria

    2015-01-01

    Full Text Available Knowledge of the radiochemical purity of radiopharmaceuticals is mandatory and can be evaluated by several methods and techniques. Planar chromatography is the technique normally employed in nuclear medicine since it is simple, rapid and usually of low cost. There is no standard system for the chromatographic technique, but price, separation efficiency and short time for execution must be considered. We have studied an alternative system using common chromatographic stationary phase and alcohol or alcohol:chloroform mixtures as the mobile phase, using the lipophilic radiopharmaceutical [99mTc(MIBI6]+ as a model. Whatman 1 modified phase paper and absolute ethanol, Whatman 1 paper and methanol:chloroform (25:75, Whatman 3MM paper and ethanol:chloroform (25:75, and the more expensive ITLC-SG and 1-propanol:chloroform (10:90 were suitable systems for the direct determination of radiochemical purity of [99mTc(MIBI6]+ since impurities such as 99mTc-reduced-hydrolyzed (RH, 99mTcO4 - and [99mTc(cysteine2]- complex were completely separated from the radiopharmaceutical, which moved toward the front of chromatographic systems while impurities were retained at the origin. The time required for analysis was 4 to 15 min, which is appropriate for nuclear medicine routines.

  14. Miniaturized chromatographic radiochemical procedure for 131I - MIBG

    International Nuclear Information System (INIS)

    Barboza, M.F. de; Pereira, N.S. de; Colturato, M.T.; Silva, C.P.G. da.

    1989-12-01

    Different solvents were used in paper chromatographic methods to obtain the best system in routine radiochemical control for 131 I-MIBG produced at IPEN-CNEN/SP. The dates were compared with those obtained with eletrophoresis method in buffer acetate, pH=4.5, 350V, during 40 minutes. The stability of the labeled compound store under 4 0 C was studied during 15 days. Miniaturized chromatographic procedures were established using Whatman 3MM (8x1cm) and n-butanol-:acetic acid: water (S:2:1) as a solvent. the Rf values were: 0.3 (I - ) and 1.0 (MIBG). The radiochemical purity was 99.3 and 99.2% (first day) obtained with eletrophoresis and miniaturized chromatographic procedures, respectively and, 84.7% after 15 days of its preparation. It is a rapid, practical and reproductive method. (author) [pt

  15. Characterizing the selectivity of stationary phases and organic modifiers in reversed-phase high-performance liquid chromatographic systems by a general solvation equation using gradient elution.

    Science.gov (United States)

    Du, C M; Valko, K; Bevan, C; Reynolds, D; Abraham, M H

    2000-11-01

    Retention data for a set of 69 compounds using rapid gradient elution are obtained on a wide range of reversed-phase stationary phases and organic modifiers. The chromatographic stationary phases studied are Inertsil (IN)-ODS, pentafluorophenyl, fluoro-octyl, n-propylcyano, Polymer (PLRP-S 100), and hexylphenyl. The organic solvent modifiers are 2,2,2-trifluoroethanol (TFE); 1,1,1,3,3,3-hexafluoropropan-2-ol (HFIP); isopropanol; methanol (MeOH); acetonitrile (AcN); tetrahydrofuran; 1,4-dioxane; N,N-dimethylformamide; and mixed solvents of dimethylsulfoxide (DMSO) with AcN and DMSO with MeOH (1:1). A total of 25 chromatographic systems are analyzed using a solvation equation. In general, most of the systems give reasonable statistics. The selectivity of the reversed phase-high-performance liquid chromatographic (HPLC) systems with respect to the solute's dipolarity-polarity, hydrogen-bond acidity, and basicity are reflected in correspondingly large coefficients in the solvation equation. We wanted to find the most orthogonal HPLC systems, showing the highest possible selectivity difference in order to derive molecular descriptors using the gradient retention times of a compound. We selected eight chromatographic systems that have a large range of coefficients of interest (s, a, and b) similar to those found in water-solvent partitions used previously to derive molecular descriptors. The systems selected are IN-ODS phases with AcN, MeOH, TFE, and HFIP as mobile phase, PLRP-S 100 phase with AcN, propylcyano phase with AcN and MeOH, and fluorooctyl phase with TFE. Using the retention data obtained for a compound in the selected chromatographic systems, we can estimate the molecular descriptors with the faster and simpler gradient elution method.

  16. Principles of qualitative analysis in the chromatographic context.

    Science.gov (United States)

    Valcárcel, M; Cárdenas, S; Simonet, B M; Carrillo-Carrión, C

    2007-07-27

    This article presents the state of the art of qualitative analysis in the framework of the chromatographic analysis. After establishing the differences between two main classes of qualitative analysis (analyte identification and sample classification/qualification) the particularities of instrumental qualitative analysis are commented on. Qualitative chromatographic analysis for sample classification/qualification through the so-called chromatographic fingerprint (for complex samples) or the volatiles profile (through the direct coupling headspace-mass spectrometry using the chromatograph as interface) is discussed. Next, more technical exposition of the qualitative chromatographic information is presented supported by a variety of representative examples.

  17. Amalgam-chromatographic separation of magnesium isotopes

    International Nuclear Information System (INIS)

    Klinskij, G.D.; Levkin, A.V.; Ivanov, S.A.

    1990-01-01

    Separation of magnesium isotopes within Mg(Hg)-MgI 2 system (in dimethylformamide) is conducted under amalgam-chromatographic conditions. Separation maximal degree, that is (1.09), for 24 Mg and 26 Mg and separation coefficient (α = 1.0089±0.006) are determined. Light isotopes are found to concentrate in the amalgam. Technique of thermal conversion of flows within amalgam-dimethylformamide system is suggested on the basis of reversible reaction of Ca-Mg element exchange

  18. Chromatographic separations of stereoisomers

    Energy Technology Data Exchange (ETDEWEB)

    Souter, R.W.

    1985-01-01

    This text covers both diastereomers and enantiomers; describes techniques for GC, HPLC, and other chromatographic methods; and tabulates results of various applications by both techniques and compound class. It provides current knowledge about separation mechanisms and interactions of asymmetric molecules, as well as experimental and commercial materials such as columns, instruments, and derivatization reagents. The contents also include stereoisomer separations by gas chromatography. Stereoisomer separations by high-performance liquid chromatography. Stereoisomer separations by other chromatographic techniques.

  19. Core-shell in liquid chromatography: application for determining sulphonamides in feed and meat using conventional chromatographic systems

    Directory of Open Access Journals (Sweden)

    Antonio Armentano

    2016-12-01

    Full Text Available A C18 column packed with core-shell particles was used for the chromatographic separation of sulphonamides in feed and meat by a conventional high performance liquid chromatography system coupled with a diode array detector. Two analytical methods, already used in our laboratory, have been modified without any changes in the extraction and clean-up steps and in the liquid chromatography instrumentation. Chromatographic conditions applied on a traditional 5-μm column have been optimized on a column packed with 2.6 μm core-shell particles. A binary mobile phase [acetate buffer solution at pH 4.50 and a mixture of methanol acetonitrile 50: 50 (v/v] was employed in gradient mode at the flow rate of 1.2 mL with an injection volume of 6 μL. These chromatographic conditions allow the separation of 13 sulphonamides with an entire run of 13 minutes. Preliminary studies have been carried out comparing blanks and spiked samples of feed and meat. A good resolution and the absence of interferences were achieved in chromatograms for both matrices. Since no change was made to the sample preparation, the optimized method does not require a complete revalidation and can be used to make routine analysis faster.

  20. Autonomous gas chromatograph system for Thermal Enhanced Vapor Extraction System (TEVES) proof of concept demonstration

    International Nuclear Information System (INIS)

    Peter, F.J.; Laguna, G.R.

    1996-09-01

    An autonomous gas chromatograph system was designed and built to support the Thermal Enhanced Vapor Extraction System (TEVES) demonstration. TEVES is a remediation demonstration that seeks to enhance an existing technology (vacuum extraction) by adding a new technology (soil heating). A pilot scale unit was set up at one of the organic waste disposal pits at the Sandia National Laboratories Chemical Waste Landfill (CWL) in Tech Area 3. The responsibility for engineering a major part of the process instrumentation for TEVES belonged to the Manufacturing Control Subsystems Department. The primary mission of the one-of-a-kind hardware/software system is to perform on-site gas sampling and analysis to quantify a variety of volatile organic compounds (VOCs) from various sources during TEVES operations. The secondary mission is to monitor a variety of TEVES process physical parameters such as extraction manifold temperature, pressure, humidity, and flow rate, and various subsurface pressures. The system began operation in September 1994 and was still in use on follow-on projects when this report was published

  1. Evaluation of selectivity in homologous multimodal chromatographic systems using in silico designed antibody fragment libraries.

    Science.gov (United States)

    Karkov, Hanne Sophie; Woo, James; Krogh, Berit Olsen; Ahmadian, Haleh; Cramer, Steven M

    2015-12-24

    This study describes the in silico design, surface property analyses, production and chromatographic evaluations of a diverse set of antibody Fab fragment variants. Based on previous findings, we hypothesized that the complementarity-determining regions (CDRs) constitute important binding sites for multimodal chromatographic ligands. Given that antibodies are highly diversified molecules and in particular the CDRs, we set out to examine the generality of this result. For this purpose, four different Fab fragments with different CDRs and/or framework regions of the variable domains were identified and related variants were designed in silico. The four Fab variant libraries were subsequently generated by site-directed mutagenesis and produced by recombinant expression and affinity purification to enable examination of their chromatographic retention behavior. The effects of geometric re-arrangement of the functional moieties on the multimodal resin ligands were also investigated with respect to Fab variant retention profiles by comparing two commercially available multimodal cation-exchange ligands, Capto MMC and Nuvia cPrime, and two novel multimodal ligand prototypes. Interestingly, the chromatographic data demonstrated distinct selectivity trends between the four Fab variant libraries. For three of the Fab libraries, the CDR regions appeared as major binding sites for all multimodal ligands. In contrast, the fourth Fab library displayed a distinctly different chromatographic behavior, where Nuvia cPrime and related multimodal ligand prototypes provided markedly improved selectivity over Capto MMC. Clearly, the results illustrate that the discriminating power of multimodal ligands differs between different Fab fragments. The results are promising indications that multimodal chromatography using the appropriate multimodal ligands can be employed in downstream bioprocessing for challenging selective separation of product related variants. Copyright © 2015 Elsevier B

  2. Correlations between chromatographic parameters and bioactivity predictors of potential herbicides.

    Science.gov (United States)

    Janicka, Małgorzata

    2014-08-01

    Different liquid chromatography techniques, including reversed-phase liquid chromatography on Purosphere RP-18e, IAM.PC.DD2 and Cosmosil Cholester columns and micellar liqud chromatography with a Purosphere RP-8e column and using buffered sodium dodecyl sulfate-acetonitrile as the mobile phase, were applied to study the lipophilic properties of 15 newly synthesized phenoxyacetic and carbamic acid derivatives, which are potential herbicides. Chromatographic lipophilicity descriptors were used to extrapolate log k parameters (log kw and log km) and log k values. Partitioning lipophilicity descriptors, i.e., log P coefficients in an n-octanol-water system, were computed from the molecular structures of the tested compounds. Bioactivity descriptors, including partition coefficients in a water-plant cuticle system and water-human serum albumin and coefficients for human skin partition and permeation were calculated in silico by ACD/ADME software using the linear solvation energy relationship of Abraham. Principal component analysis was applied to describe similarities between various chromatographic and partitioning lipophilicities. Highly significant, predictive linear relationships were found between chromatographic parameters and bioactivity descriptors. © The Author [2013]. Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

  3. Chromatographic hydrogen isotope separation

    International Nuclear Information System (INIS)

    Aldridge, F.T.

    1983-01-01

    Intermetallic compounds with the CaCu5 type of crystal structure, particularly LaNiCo and CaNi5, exhibit high separation factors and fast equilibrium times and therefore are useful for packing a chromatographic hydrogen isotope separation column. The addition of an inert metal to dilute the hydride improves performance of the column. A large scale multi-stage chromatographic separation process run as a secondary process off a hydrogen feedstream from an industrial plant which uses large volumes of hydrogen can produce large quantities of heavy water at an effective cost for use in heavy water reactors

  4. Chromatographic hydrogen isotope separation

    International Nuclear Information System (INIS)

    Aldridge, F.T.

    1981-01-01

    Intermetallic compounds with the CaCu5 type of crystal structure , particularly LaNiCo and CaNi5, exhibit high separation factors and fast equilibrium times and therefore are useful for packing a chromatographic hydrogen isotope separation colum. The addition of an inert metal to dilute the hydride improves performance of the column. A large scale mutli-stage chromatographic separation process run as a secondary process off a hydrogen feedstream from an industrial plant which uses large volumes of hydrogen can produce large quantities of heavy water at an effective cost for use in heavy water reactors

  5. Optimization of the gas chromatographic separations

    International Nuclear Information System (INIS)

    Gasco Sanchez, L.

    1973-01-01

    A review and a critical study on the optimization of the gas chromatographic separations are made. After dealing with the fundamental gas chromatographic equations, some methods of expressing column performances are discussed: performance indices, performance parameters, resolution and effective plate number per unit time. This is completed with a comparative study on performances of various types of columns. Moreover, optimization methods for operating chromatographic conditions are extensively dealt with: as resolution optimization, separation time, and normalization techniques for the time of analysis in order to achieve the maximum resolution at constant time. Finally, some others non operating parameters such as: selectivity of stationary phases, column preparation and optimization methods by means of computers are studied. (Author) 68 refs

  6. A Small-Scale Low-Cost Gas Chromatograph

    Science.gov (United States)

    Gros, Natasa; Vrtacnik, Margareta

    2005-01-01

    The design and application of a small-scale portable gas chromatograph for learning of the basic concepts of chromatography is described. The apparatus consists of two basic separable units, which includes a chromatographic unit and an electronic unit.

  7. Alternative chromatographic system for the quality control of lipophilic technetium-99m radiopharmaceuticals such as [{sup 99m}Tc(MIBI){sub 6}]{sup +}

    Energy Technology Data Exchange (ETDEWEB)

    Faria, D.P.; Buchpiguel, C.A.; Marques, F.L.N., E-mail: danielefaria1@gmail.com [Universidade de Sao Paulo (USP), Sao Paulo, SP (Brazil). Faculdade de Medicina. Departamento de Radiologia. Servico de Medicina Nuclear

    2015-10-15

    Knowledge of the radiochemical purity of radiopharmaceuticals is mandatory and can be evaluated by several methods and techniques. Planar chromatography is the technique normally employed in nuclear medicine since it is simple, rapid and usually of low cost. There is no standard system for the chromatographic technique, but price, separation efficiency and short time for execution must be considered. We have studied an alternative system using common chromatographic stationary phase and alcohol or alcohol:chloroform mixtures as the mobile phase, using the lipophilic radiopharmaceutical [{sup 99m}Tc(MIBI){sub 6}]{sup +} as a model. Whatman 1 modified phase paper and absolute ethanol, Whatman 1 paper and methanol: chloroform (25:75), Whatman 3MM paper and ethanol:chloroform (25:75), and the more expensive ITLC-SG and 1-propanol: chloroform (10:90) were suitable systems for the direct determination of radiochemical purity of [{sup 99m}Tc(MIBI){sub 6}]{sup +} since impurities such as {sup 99m}Tc-reduced-hydrolyzed (RH), {sup 99m}TcO4{sup -} and [{sup 99m}Tc(cysteine){sub 2}]{sup -} complex were completely separated from the radiopharmaceutical, which moved toward the front of chromatographic systems while impurities were retained at the origin. The time required for analysis was 4 to 15 min, which is appropriate for nuclear medicine routines. (author)

  8. Determination of solute descriptors by chromatographic methods

    International Nuclear Information System (INIS)

    Poole, Colin F.; Atapattu, Sanka N.; Poole, Salwa K.; Bell, Andrea K.

    2009-01-01

    The solvation parameter model is now well established as a useful tool for obtaining quantitative structure-property relationships for chemical, biomedical and environmental processes. The model correlates a free-energy related property of a system to six free-energy derived descriptors describing molecular properties. These molecular descriptors are defined as L (gas-liquid partition coefficient on hexadecane at 298 K), V (McGowan's characteristic volume), E (excess molar refraction), S (dipolarity/polarizability), A (hydrogen-bond acidity), and B (hydrogen-bond basicity). McGowan's characteristic volume is trivially calculated from structure and the excess molar refraction can be calculated for liquids from their refractive index and easily estimated for solids. The remaining four descriptors are derived by experiment using (largely) two-phase partitioning, chromatography, and solubility measurements. In this article, the use of gas chromatography, reversed-phase liquid chromatography, micellar electrokinetic chromatography, and two-phase partitioning for determining solute descriptors is described. A large database of experimental retention factors and partition coefficients is constructed after first applying selection tools to remove unreliable experimental values and an optimized collection of varied compounds with descriptor values suitable for calibrating chromatographic systems is presented. These optimized descriptors are demonstrated to be robust and more suitable than other groups of descriptors characterizing the separation properties of chromatographic systems.

  9. Determination of solute descriptors by chromatographic methods.

    Science.gov (United States)

    Poole, Colin F; Atapattu, Sanka N; Poole, Salwa K; Bell, Andrea K

    2009-10-12

    The solvation parameter model is now well established as a useful tool for obtaining quantitative structure-property relationships for chemical, biomedical and environmental processes. The model correlates a free-energy related property of a system to six free-energy derived descriptors describing molecular properties. These molecular descriptors are defined as L (gas-liquid partition coefficient on hexadecane at 298K), V (McGowan's characteristic volume), E (excess molar refraction), S (dipolarity/polarizability), A (hydrogen-bond acidity), and B (hydrogen-bond basicity). McGowan's characteristic volume is trivially calculated from structure and the excess molar refraction can be calculated for liquids from their refractive index and easily estimated for solids. The remaining four descriptors are derived by experiment using (largely) two-phase partitioning, chromatography, and solubility measurements. In this article, the use of gas chromatography, reversed-phase liquid chromatography, micellar electrokinetic chromatography, and two-phase partitioning for determining solute descriptors is described. A large database of experimental retention factors and partition coefficients is constructed after first applying selection tools to remove unreliable experimental values and an optimized collection of varied compounds with descriptor values suitable for calibrating chromatographic systems is presented. These optimized descriptors are demonstrated to be robust and more suitable than other groups of descriptors characterizing the separation properties of chromatographic systems.

  10. Validation for chromatographic and electrophoretic methods

    OpenAIRE

    Ribani, Marcelo; Bottoli, Carla Beatriz Grespan; Collins, Carol H.; Jardim, Isabel Cristina Sales Fontes; Melo, Lúcio Flávio Costa

    2004-01-01

    The validation of an analytical method is fundamental to implementing a quality control system in any analytical laboratory. As the separation techniques, GC, HPLC and CE, are often the principal tools used in such determinations, procedure validation is a necessity. The objective of this review is to describe the main aspects of validation in chromatographic and electrophoretic analysis, showing, in a general way, the similarities and differences between the guidelines established by the dif...

  11. An automated multidimensional preparative gas chromatographic system for isolation and enrichment of trace amounts of xenon from ambient air.

    Science.gov (United States)

    Larson, Tuula; Östman, Conny; Colmsjö, Anders

    2011-04-01

    The monitoring of radioactive xenon isotopes is one of the principal methods for the detection of nuclear explosions in order to identify clandestine nuclear testing. In this work, a miniaturized, multiple-oven, six-column, preparative gas chromatograph was constructed in order to isolate trace quantities of radioactive xenon isotopes from ambient air, utilizing nitrogen as the carrier gas. The multidimensional chromatograph comprised preparative stainless steel columns packed with molecular sieves, activated carbon, and synthetic carbon adsorbents (e.g., Anasorb®-747 and Carbosphere®). A combination of purification techniques--ambient adsorption, thermal desorption, back-flushing, thermal focusing, and heart cutting--was selectively optimized to produce a well-defined xenon peak that facilitated reproducible heart cutting and accurate quantification. The chromatographic purification of a sample requires approximately 4 h and provides complete separation of xenon from potentially interfering components (such as water vapor, methane, carbon dioxide, and radon) with recovery and accuracy close to 100%. The preparative enrichment process isolates and concentrates a highly purified xenon gas fraction that is suitable for subsequent ultra-low-level γ-, ß/γ-spectroscopic or high-resolution mass spectrometric measurement (e.g., to monitor the gaseous fission products of nuclear explosions at remote locations). The Xenon Processing Unit is a free-standing, relatively lightweight, and transportable system that can be interfaced to a variety of sampling and detection systems. It has a relatively inexpensive, rugged, and compact modular (19-inch rack) design that provides easy access to all parts for maintenance and has a low power requirement.

  12. Parameter selection for peak alignment in chromatographic sample profiling: Objective quality indicators and use of control samples

    NARCIS (Netherlands)

    Peters, S.; van Velzen, E.; Janssen, H.-G.

    2009-01-01

    In chromatographic profiling applications, peak alignment is often essential as most chromatographic systems exhibit small peak shifts over time. When using currently available alignment algorithms, there are several parameters that determine the outcome of the alignment process. Selecting the

  13. Determination of hexachlorocyclohexane pesticide residues in wool fat by a combined high-performance liquid chromatographic-gas-liquid chromatographic method

    International Nuclear Information System (INIS)

    Ali, S.L.

    1978-01-01

    Beta- and gamma-hexachlorocyclohexane residues were determined in twelve wool fat samples by using a combined high-performance liquid chromatographic (HPLC)-gas-liquid chromatographic (GLC) method. After extraction and chromatographic clean-up on a silca-gel column, the sample was further purified by HPLC on a reversed-phase C-18 column with methanol as the mobile phase. The final determination was effected by GLC with a 1-mCi nickel-63 electron-capture detector. The analytical method was checked by addition of carbon-14-labelled lindane and measurement of the radioactivity in a liquid scintillation counter. (Auth.)

  14. Probabilistic peak detection for first-order chromatographic data.

    Science.gov (United States)

    Lopatka, M; Vivó-Truyols, G; Sjerps, M J

    2014-03-19

    We present a novel algorithm for probabilistic peak detection in first-order chromatographic data. Unlike conventional methods that deliver a binary answer pertaining to the expected presence or absence of a chromatographic peak, our method calculates the probability of a point being affected by such a peak. The algorithm makes use of chromatographic information (i.e. the expected width of a single peak and the standard deviation of baseline noise). As prior information of the existence of a peak in a chromatographic run, we make use of the statistical overlap theory. We formulate an exhaustive set of mutually exclusive hypotheses concerning presence or absence of different peak configurations. These models are evaluated by fitting a segment of chromatographic data by least-squares. The evaluation of these competing hypotheses can be performed as a Bayesian inferential task. We outline the potential advantages of adopting this approach for peak detection and provide several examples of both improved performance and increased flexibility afforded by our approach. Copyright © 2014 Elsevier B.V. All rights reserved.

  15. A novel two-dimensional liquid chromatographic system for the online toxicity prediction of pharmaceuticals and related substances

    Energy Technology Data Exchange (ETDEWEB)

    Li, Jian; Xu, Li [Tongji School of Pharmacy, Huazhong University of Science and Technology, Wuhan 430030 (China); Shi, Zhi-guo, E-mail: shizg@whu.edu.cn [Department of Chemistry, Wuhan University, Wuhan 430072 (China); Hu, Min [Hubei Instrument for Food and Drug Control, Wuhan (China)

    2015-08-15

    Highlights: • A novel two-dimensional liquid chromatographic system was developed. • The 1st dimension was ODS to separate components in the sample. • The 2nd dimension was biopartitioning micellar chromatography to predict toxicity. • The system was used to screen toxicity of pharmaceuticals and related substances. • It was promising for fast online toxicity screening of complex sample in one step. - Abstract: In this study, a novel two-dimensional liquid chromatographic (2D-LC) system was developed for simultaneous separation and toxicity prediction of pharmaceutical and its related substances. A conventional ODS column was used on the 1st-D to separate the sample; while, bio-partitioning micellar chromatography served as the 2nd-D to predict toxicity of the components. The established system was tested for the toxicity of ibuprofen and its impurities with known toxicity. With only one injection, ibuprofen and its impurities were separated on the 1st-D; and LC50 values of individual impurity were obtained based on the quantitative retention–activity relationships, which agreed well with the reported data. Furthermore, LC50 values of photolysis transformation products (TPs) of carprofen, ketoprofen and diclofenac acid (as unknown compounds) were screened in this 2D-LC system, which could be an indicator of the toxicity of these TPs and was meaningful for the environmental monitoring and drinking water treatment. The established 2D-LC system was cost-effective, time-saving and reliable, and was promising for fast online screening of toxicity of known and unknown analytes in the complex sample in a single step. It may find applications in environment, pharmaceutical and food, etc.

  16. A novel two-dimensional liquid chromatographic system for the online toxicity prediction of pharmaceuticals and related substances

    International Nuclear Information System (INIS)

    Li, Jian; Xu, Li; Shi, Zhi-guo; Hu, Min

    2015-01-01

    Highlights: • A novel two-dimensional liquid chromatographic system was developed. • The 1st dimension was ODS to separate components in the sample. • The 2nd dimension was biopartitioning micellar chromatography to predict toxicity. • The system was used to screen toxicity of pharmaceuticals and related substances. • It was promising for fast online toxicity screening of complex sample in one step. - Abstract: In this study, a novel two-dimensional liquid chromatographic (2D-LC) system was developed for simultaneous separation and toxicity prediction of pharmaceutical and its related substances. A conventional ODS column was used on the 1st-D to separate the sample; while, bio-partitioning micellar chromatography served as the 2nd-D to predict toxicity of the components. The established system was tested for the toxicity of ibuprofen and its impurities with known toxicity. With only one injection, ibuprofen and its impurities were separated on the 1st-D; and LC50 values of individual impurity were obtained based on the quantitative retention–activity relationships, which agreed well with the reported data. Furthermore, LC50 values of photolysis transformation products (TPs) of carprofen, ketoprofen and diclofenac acid (as unknown compounds) were screened in this 2D-LC system, which could be an indicator of the toxicity of these TPs and was meaningful for the environmental monitoring and drinking water treatment. The established 2D-LC system was cost-effective, time-saving and reliable, and was promising for fast online screening of toxicity of known and unknown analytes in the complex sample in a single step. It may find applications in environment, pharmaceutical and food, etc

  17. High-performance liquid-chromatographic separation of subcomponents of antimycin-A

    Science.gov (United States)

    Abidi, S.L.

    1988-01-01

    Using a reversed-phase high-performance liquid chromatographic (HPLC) technique, a mixture of antimycins A was separated into eight hitherto unreported subcomponents, Ala, Alb, A2a, A2b, A3a, A3b, A4a, and A4b. Although a base-line resolution of the known four major antimycins Al, A2, A3, and A4 was readily achieved with mobile phases containing acetate buffers, the separation of the new antibiotic subcomponents was highly sensitive to variation in mobile phase conditions. The type and composition of organic modifiers, the nature of buffer salts, and the concentration of added electrolytes had profound effects on capacity factors, separation factors, and peak resolution values. Of the numerous chromatographic systems examined, a mobile phase consisting of methanol-water (70:30) and 0.005 M tetrabutylammonium phosphate at pH 3.0 yielded the most satisfactory results for the separation of the subcomponents. Reversed-phase gradient HPLC separation of the dansylated or methylated antibiotic compounds produced superior chromatographic characteristics and the presence of added electrolytes was not a critical factor for achieving separation. Differences in the chromatographic outcome between homologous and structural isomers were interpretated based on a differential solvophobic interaction rationale. Preparative reversed-phase HPLC under optimal conditions enabled isolation of pure samples of the methylated antimycin subcomponents for use in structural studies.

  18. Chromatographic measurement of hydrogen isotopic and permanent gas impurities in tritium

    International Nuclear Information System (INIS)

    Warner, D.K.; Kinard, C.; Bohl, D.C.

    1976-01-01

    This paper describes a gas chromatograph that was designed for dedicated analysis of hydrogen isotopic and permanent gas impurities in tritium and tritium-deuterium mixtures. The instrument that was developed substantially improved the accuracy and precision of hydrogen isotopic analysis in the 20 ppM to one mole percent range as compared with other analytical methods. Several unique design features of the instrument were required due to the radiation and isotopic exchange properties of the tritium in the samples; descriptions of these features are presented along with details of the complete chromatographic system. The experimental procedures used to calibrate the detector and statistically evaluate its performance are given, and the sources of analytical error are cited. The limitations of the present system are also discussed

  19. Improved Chromatographic Bioavailability Estimations

    National Research Council Canada - National Science Library

    Dorsey, John

    1996-01-01

    .... Since the inception of reversed phase liquid chromatography there have been many attempts to correlate chromatographic retention with bioavailability and the most often used bulk measure, the octanol...

  20. A chromatographic determination of water in non-aqueous phases of solvent extraction systems

    International Nuclear Information System (INIS)

    Lyle, S.J.; Smith, D.B.

    1975-01-01

    The disadvantages of the Karl Fischer method for the determination of water in the non-aqueous phases of solvent extraction systems are pointed out, and a gas chromatographic method is described which is claimed to be potentially capable of overcoming these disadvantages. The method, as described, was developed to satisfy conditions relevant to measurement of the transfer rate of water from an aqueous phase into tri-n-butylphosphate in toluene, but it can be used for water determination in other solvent extraction systems. The apparatus used is described in detail. The concentration of water in water-saturated TBP was found to be 3.56 mol/litre, compared with a value of 3.55 obtained by Karl Fischer titration and previous literature values of 3.59 and 3.57. Measurements of water content in benzene solutions of long chain alkylamines were also sucessfully carried out. (U.K.)

  1. Spectrophotometric high-precision seawater pH determination for use in underway measuring systems

    Directory of Open Access Journals (Sweden)

    S. Aßmann

    2011-10-01

    Full Text Available Autonomous sensors are required for a comprehensive documentation of the changes in the marine carbon system and thus to differentiate between its natural variability and anthropogenic impacts. Spectrophotometric determination of pH – a key variable of the seawater carbon system – is particularly suited to achieve precise and drift-free measurements. However, available spectrophotometric instruments are not suitable for integration into automated measurement systems (e.g. FerryBox since they do not meet the major requirements of reliability, stability, robustness and moderate cost. Here we report on the development and testing of a~new indicator-based pH sensor that meets all of these requirements. This sensor can withstand the rough conditions during long-term deployments on ships of opportunity and is applicable to the open ocean as well as to coastal waters with a complex matrix and highly variable conditions. The sensor uses a high resolution CCD spectrometer as detector connected via optical fibers to a custom-made cuvette designed to reduce the impact of air bubbles. The sample temperature can be precisely adjusted (25 °C ± 0.006 °C using computer-controlled power supplies and Peltier elements thus avoiding the widely used water bath. The overall setup achieves a measurement frequency of 1 min−1 with a precision of ±0.0007 pH units, an average offset of +0.0005 pH units to a reference system, and an offset of +0.0081 pH units to a certified standard buffer. Application of this sensor allows monitoring of seawater pH in autonomous underway systems, providing a key variable for characterization and understanding of the marine carbon system.

  2. Improved Submariner Eyewear for Routine Wear and Emergency Equipment Use Underway

    Science.gov (United States)

    2010-01-15

    information. 2.0 DESCRIPTION Naval Submarine Medical Research Laboratory (NSMRL) is seeking information from the eyewear industry that will provide...Improved Submariner Eyewear for Routine Wear and Emergency Equipment Use Underway by Alison America, MA Wayne G. Horn, MD...Submariner Eyewear for Routine Wear and Emergency Equipment Use Underway 50818 Alison America, MA Wayne G. Horn, MD Naval Submarine Medical Research

  3. QSAR models for prediction of chromatographic behavior of homologous Fab variants.

    Science.gov (United States)

    Robinson, Julie R; Karkov, Hanne S; Woo, James A; Krogh, Berit O; Cramer, Steven M

    2017-06-01

    While quantitative structure activity relationship (QSAR) models have been employed successfully for the prediction of small model protein chromatographic behavior, there have been few reports to date on the use of this methodology for larger, more complex proteins. Recently our group generated focused libraries of antibody Fab fragment variants with different combinations of surface hydrophobicities and electrostatic potentials, and demonstrated that the unique selectivities of multimodal resins can be exploited to separate these Fab variants. In this work, results from linear salt gradient experiments with these Fabs were employed to develop QSAR models for six chromatographic systems, including multimodal (Capto MMC, Nuvia cPrime, and two novel ligand prototypes), hydrophobic interaction chromatography (HIC; Capto Phenyl), and cation exchange (CEX; CM Sepharose FF) resins. The models utilized newly developed "local descriptors" to quantify changes around point mutations in the Fab libraries as well as novel cluster descriptors recently introduced by our group. Subsequent rounds of feature selection and linearized machine learning algorithms were used to generate robust, well-validated models with high training set correlations (R 2  > 0.70) that were well suited for predicting elution salt concentrations in the various systems. The developed models then were used to predict the retention of a deamidated Fab and isotype variants, with varying success. The results represent the first successful utilization of QSAR for the prediction of chromatographic behavior of complex proteins such as Fab fragments in multimodal chromatographic systems. The framework presented here can be employed to facilitate process development for the purification of biological products from product-related impurities by in silico screening of resin alternatives. Biotechnol. Bioeng. 2017;114: 1231-1240. © 2016 Wiley Periodicals, Inc. © 2016 Wiley Periodicals, Inc.

  4. Effects of chromatographic fractions of Euphorbia hirta on the rat ...

    African Journals Online (AJOL)

    The effects of the chromatographic fractions of Euphorbia hirta Linn on the serum biochemical parameters in rats were investigated. The ethanolic extract of this plant was subjected to chromatographic separation using the vacuum liquid chromatographic technique, a modified form of classical column chromatography.

  5. Conceptual design of hydrogen isotopes chromatographic separation system with super large capacity

    International Nuclear Information System (INIS)

    Xie Bo; Weng Kuiping; Liu Yunnu; Hou Jianping

    2012-01-01

    A super large capacity hydrogen isotopes separation system, including total plan, unit (including making and purification of gas, three-grade chromatographic columns, gas loop and auto-control, and carrier recovery) and experimental scheme, had been designed on the basis of a series of hydrogen-deuterium experiments by temperature programmed de- sorption. The characteristic of the system was that desorption kinetic parameters could be directly calculated from the hydrogen isotope separation desorption spectra information. In other words, the complicated dynamic process of separation could be described by the desorption rate equation, shape parameter and desorption activation energy calculation on the condition of the experimental data and appropriate assumptions (equilibrium and adsorption, uniform surface). In previous work, an experimental series of operation to verify the successive enrichment of D 2 from a H 2 -D 2 mixture, the production of the deuterium from natural hydrogen and the recovery of tritium such as from the nuclear heavy-water were carried out using MS5A at 77 K. This work was only conceptual design, so it was necessary to identify the availability of super large capacity system by experiment. (authors)

  6. A mobile automatic gas chromatograph system to measure CO2, CH4 and N2O fluxes from soil in the field

    International Nuclear Information System (INIS)

    Silvola, J.; Martikainen, P.; Nykaenen, H.

    1992-01-01

    A caravan has been converted into mobile laboratory for measuring fluxes of CO 2 , CH 4 and N 2 O from the soil in the field. The caravan was equipped with a gas chromatograph fitted with TC-, FI- and EC-detectors, and a PC controlled data logger. The gas collecting chambers can be used up to 50 m from the caravan. The closing and opening of the chambers, as well as the flows of sample gases from chambers to the gas chromatograph. is pneumatically regulated. Simultaneous recordings of temperature, light intensity and the depth of water table are made. The system has been used for two months in 1992, and some preliminary results are presented

  7. Vibrational Spectroscopy of Chromatographic Interfaces

    Energy Technology Data Exchange (ETDEWEB)

    Jeanne E. Pemberton

    2011-03-10

    Chromatographic separations play a central role in DOE-supported fundamental research related to energy, biological systems, the environment, and nuclear science. The overall portfolio of research activities in the Separations and Analysis Program within the DOE Office of Basic Energy Sciences includes support for activities designed to develop a molecular-level understanding of the chemical processes that underlie separations for both large-scale and analytical-scale purposes. The research effort funded by this grant award was a continuation of DOE-supported research to develop vibrational spectroscopic methods to characterize the interfacial details of separations processes at a molecular level.

  8. A Gas Chromatographic Continuous Emissions Monitoring System for the Determination of VOCs and HAPs.

    Science.gov (United States)

    Coleman, William M; Gordon, Bert M

    1996-01-01

    This article describes a new gas chromatography-based emissions monitoring system for measuring volatile organic compounds (VOCs) and hazardous air pollutants (HAPs). The system is composed of a dual-column gas chromatograph equipped with thermal conductivity detectors, in which separation is optimized for fast chromatography. The system has the necessary valving for stream selection, which allows automatic calibration of the system at predetermined times and successive measurement of individual VOCs before and after a control device. Nine different VOCs (two of which are HAPs), plus methane (CH4) and carbon dioxide (CO2) are separated and quantified every two minutes. The accuracy and precision of this system has been demonstrated to be greater than 95%. The system employs a mass flow measurement device and also calculates and displays processed emission data, such as control device efficiency and total weight emitted during given time periods. Two such systems have been operational for one year in two separate gravure printing facilities; minimal upkeep is required, about one hour per month. One of these systems, used before and after a carbon adsorber, has been approved by the pertinent local permitting authority.

  9. Probabilistic peak detection for first-order chromatographic data

    NARCIS (Netherlands)

    Lopatka, M.; Vivó-Truyols, G.; Sjerps, M.J.

    2014-01-01

    We present a novel algorithm for probabilistic peak detection in first-order chromatographic data. Unlike conventional methods that deliver a binary answer pertaining to the expected presence or absence of a chromatographic peak, our method calculates the probability of a point being affected by

  10. Second-order Data by Flow Injection Analysis with Spectrophotometric Diode-array Detection and Incorporated Gel-filtration Chromatographic Column

    DEFF Research Database (Denmark)

    Bechmann, Iben Ellegaard

    1997-01-01

    A flow injection analysis (FIA) system furnished with a gel-filtration chromatographic column and with photodiode-array detection was used for the generation of second-order data. The system presented is a model system in which the analytes are blue dextran, potassium hexacyanoferrate(III) and he......A flow injection analysis (FIA) system furnished with a gel-filtration chromatographic column and with photodiode-array detection was used for the generation of second-order data. The system presented is a model system in which the analytes are blue dextran, potassium hexacyanoferrate...

  11. Use of laminar chromatographic methods for determination of separation conditions in column extraction chromatography

    International Nuclear Information System (INIS)

    Ghersini, G.; Cerrai, E.

    1978-01-01

    Possibilities of using laminar chromatographic methods (paper and thin-layer chromatography) to determine optimal separation conditions in column extraction chromatography are analysed. Most of the given laminar methods are presented as Rf-spectra, i.e. as dependences of Rf found experimentally on eluating solution component concentration. Interrelation between Rf and distribution coefficients of corresponding liquid extraction systems and retention volumes of chromatographic columns is considered. Literature data on extraction paper and thin-layer chromatography of elements with various immovable phases are presented

  12. Research Ship Atlantic Explorer Underway Meteorological Data, Quality Controlled

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Research Ship Atlantic Explorer Underway Meteorological Data (delayed ~10 days for quality control) are from the Shipboard Automated Meteorological and Oceanographic...

  13. Research Ship Roger Revelle Underway Meteorological Data, Quality Controlled

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Research Ship Roger Revelle Underway Meteorological Data (delayed ~10 days for quality control) are from the Shipboard Automated Meteorological and Oceanographic...

  14. Research Ship New Horizon Underway Meteorological Data, Quality Controlled

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Research Ship New Horizon Underway Meteorological Data (delayed ~10 days for quality control) are from the Shipboard Automated Meteorological and Oceanographic...

  15. Research Ship Aurora Australis Underway Meteorological Data, Quality Controlled

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Research Ship Aurora Australis Underway Meteorological Data (delayed ~10 days for quality control) are from the Shipboard Automated Meteorological and Oceanographic...

  16. Research Ship Southern Surveyor Underway Meteorological Data, Quality Controlled

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Research Ship Southern Surveyor Underway Meteorological Data (delayed ~10 days for quality control) are from the Shipboard Automated Meteorological and Oceanographic...

  17. NOAA Ship Okeanos Explorer Underway Meteorological Data, Quality Controlled

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NOAA Ship Okeanos Explorer Underway Meteorological Data (delayed ~10 days for quality control) are from the Shipboard Automated Meteorological and Oceanographic...

  18. Radio-chromatographic determination of plasmatic adenosine deaminase (A.D.)

    International Nuclear Information System (INIS)

    Chivot, J.J.; Depernet, D.; Caen, J.

    1970-01-01

    We were able, by using a radio-chromatographic method, to measure an adenosine deaminase activity in normal human heparinized platelet-poor plasma, which can degrade 0.016 μM adenosine. This activity suppressed by heating 56 C for 30 minutes is inhibited by high concentrations of urea and is proportional to the amount of plasma, source of enzyme, in the systems. (authors) [fr

  19. Gas chromatographic isolation technique for compound-specific radiocarbon analysis

    International Nuclear Information System (INIS)

    Uchida, M.; Kumamoto, Y.; Shibata, Y.; Yoneda, M.; Morita, M.; Kawamura, K.

    2002-01-01

    Full text: We present here a gas chromatographic isolation technique for the compound-specific radiocarbon analysis of biomarkers from the marine sediments. The biomarkers of fatty acids, hydrocarbon and sterols were isolated with enough amount for radiocarbon analysis using a preparative capillary gas chromatograph (PCGC) system. The PCGC systems used here is composed of an HP 6890 GC with FID, a cooled injection system (CIS, Gerstel, Germany), a zero-dead-volume effluent splitter, and a cryogenic preparative collection device (PFC, Gerstel). For AMS analysis, we need to separate and recover sufficient quantity of target individual compounds (>50 μgC). Yields of target compounds from C 14 n-alkanes to C 40 to C 30 n-alkanes and approximately that of 80% for higher molecular weights compounds more than C 30 n-alkanes. Compound specific radiocarbon analysis of organic compounds, as well as compound-specific stable isotope analysis, provide valuable information on the origins and carbon cycling in marine system. Above PCGC conditions, we applied compound-specific radiocarbon analysis to the marine sediments from western north Pacific, which showed the possibility of a useful chronology tool for estimating the age of sediment using organic matter in paleoceanographic study, in the area where enough amounts of planktonic foraminifera for radiocarbon analysis by accelerator mass spectrometry (AMS) are difficult to obtain due to dissolution of calcium carbonate. (author)

  20. Implementation of a fully automated process purge-and-trap gas chromatograph at an environmental remediation site

    International Nuclear Information System (INIS)

    Blair, D.S.; Morrison, D.J.

    1997-01-01

    The AQUASCAN, a commercially available, fully automated purge-and-trap gas chromatograph from Sentex Systems Inc., was implemented and evaluated as an in-field, automated monitoring system of contaminated groundwater at an active DOE remediation site in Pinellas, FL. Though the AQUASCAN is designed as a stand alone process analytical unit, implementation at this site required additional hardware. The hardware included a sample dilution system and a method for delivering standard solution to the gas chromatograph for automated calibration. As a result of the evaluation the system was determined to be a reliable and accurate instrument. The AQUASCAN reported concentration values for methylene chloride, trichloroethylene, and toluene in the Pinellas ground water were within 20% of reference laboratory values

  1. Gas-Chromatographic Determination Of Water In Freon PCA

    Science.gov (United States)

    Melton, Donald M.

    1994-01-01

    Gas-chromatographic apparatus measures small concentrations of water in specimens of Freon PCA. Testing by use of apparatus faster and provides greater protection against accidental contamination of specimens by water in testing environment. Automated for unattended operation. Also used to measure water contents of materials, other than Freon PCA. Innovation extended to development of purgeable sampling accessory for gas chromatographs.

  2. Technical artifacts in chromatographic analysis of Tc-99m radiopharmaceuticals

    International Nuclear Information System (INIS)

    Kowalsky, R.J.; Creekmore, J.R.

    1982-01-01

    Technical artifacts produced during chromatographic analysis of technetium radiopharmaceuticals were investigated. Such artifacts are, we found, caused by improper spotting and drying techniques; these in turn produce spuriously high impurities in Tc-99m complexes of DTPA, MDP, PPi, and GH. The ITLC-SG/acetone system produces considerable streaking of Tc-complex if the applied spot is large and not dried before development. This results in activity in the solvent front portion of the chromatographic strip indicating falsely high levels of pertechnetate impurity. Proper drying of the applied spot eliminates the artifact. The ITLC-SG/saline system yields falsely high, hydrolyzed-reduced technetium impurities if the spot is allowed to enter the solvent during development. Correct spot placement and size eliminate this problem. Strips that are allowed to dry in room air for several minutes may indicate considerable pertechnetate impurity on the chromatogram; yet this may not actually be present in the radiopharmaceutical vial. Drying spots rapidly with hot air or in a nitrogen atmosphere before development eliminates this problem

  3. Estimations of temperature deviations in chromatographic columns using isenthalpic plots. I. Theory for isocratic systems.

    Science.gov (United States)

    Tarafder, Abhijit; Iraneta, Pamela; Guiochon, Georges; Kaczmarski, Krzysztof; Poe, Donald P

    2014-10-31

    We propose to use constant enthalpy or isenthalpic diagrams as a tool to estimate the extent of the temperature variations caused by the mobile phase pressure drop along a chromatographic column, e.g. of its cooling in supercritical fluid and its heating in ultra-performance liquid chromatography. Temperature strongly affects chromatographic phenomena. Any of its variations inside the column, whether intended or not, can lead to significant changes in separation performance. Although instruments use column ovens in order to keep constant the column temperature, operating conditions leading to a high pressure drop may cause significant variations of the column temperature, both in the axial and the radial directions, from the set value. Different ways of measuring these temperature variations are available but they are too inconvenient to be employed in many practical situations. In contrast, the thermodynamic plot-based method that we describe here can easily be used with only a ruler and a pencil. They should be helpful in developing methods or in analyzing results in analytical laboratories. Although the most effective application area for this approach should be SFC (supercritical fluid chromatography), it can be applied to any chromatographic conditions in which temperature variations take place along the column due to the pressure drop, e.g. in ultra-high pressure liquid chromatography (UHPLC). The method proposed here is applicable to isocractic conditions only. Copyright © 2014 Elsevier B.V. All rights reserved.

  4. Multiple chromatographic fingerprinting and its application to the quality control of herbal medicines

    International Nuclear Information System (INIS)

    Fan Xiaohui; Cheng Yiyu; Ye Zhengliang; Lin Ruichao; Qian Zhongzhi

    2006-01-01

    Recently, chromatographic fingerprinting has become one of the most powerful approaches to quality control of herbal medicines. However, the performance of reported chromatographic fingerprinting constructed by single chromatogram sometimes turns out to be inadequate for complex herbal medicines, such as multi-herb botanical drug products. In this study, multiple chromatographic fingerprinting, which consists of more than one chromatographic fingerprint and represents the whole characteristics of chemical constitutions of the complex medicine, is proposed as a potential strategy in this complicated case. As a typical example, a binary chromatographic fingerprinting of 'Danshen Dropping Pill' (DSDP), the best-sold traditional Chinese medicine in China, was developed. First, two HPLC fingerprints that, respectively, represent chemical characteristics of depsides and saponins of DSDP were developed, which were used to construct binary chromatographic fingerprints of DSDP. Moreover, the authentication and validation of the binary fingerprints were performed. Then, a data-level information fusion method was employed to capture the chemical information encoded in two chromatographic fingerprints. Based on the fusion results, the lot-to-lot consistency and frauds can be determined either using similarity measure or by chemometrics approach. The application of binary chromatographic fingerprinting to consistency assessment and frauds detection of DSDP clearly demonstrated that the proposed method was a powerful approach to quality control of complex herbal medicines

  5. High-Order Approximation of Chromatographic Models using a Nodal Discontinuous Galerkin Approach

    DEFF Research Database (Denmark)

    Meyer, Kristian; Huusom, Jakob Kjøbsted; Abildskov, Jens

    2018-01-01

    by Javeed et al. (2011a,b, 2013) with an efficient quadrature-free implementation. The framework is used to simulate linear and non-linear multicomponent chromatographic systems. The results confirm arbitrary high-order accuracy and demonstrate the potential for accuracy and speed-up gains obtainable...

  6. Research Ship Nathaniel B. Palmer Underway Meteorological Data, Quality Controlled

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Research Ship Nathaniel B. Palmer Underway Meteorological Data (delayed ~10 days for quality control) are from the Shipboard Automated Meteorological and...

  7. Research Ship Robert Gordon Sproul Underway Meteorological Data, Quality Controlled

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Research Ship Robert Gordon Sproul Underway Meteorological Data (delayed ~10 days for quality control) are from the Shipboard Automated Meteorological and...

  8. [Similarity system theory to evaluate similarity of chromatographic fingerprints of traditional Chinese medicine].

    Science.gov (United States)

    Liu, Yongsuo; Meng, Qinghua; Jiang, Shumin; Hu, Yuzhu

    2005-03-01

    The similarity evaluation of the fingerprints is one of the most important problems in the quality control of the traditional Chinese medicine (TCM). Similarity measures used to evaluate the similarity of the common peaks in the chromatogram of TCM have been discussed. Comparative studies were carried out among correlation coefficient, cosine of the angle and an improved extent similarity method using simulated data and experimental data. Correlation coefficient and cosine of the angle are not sensitive to the differences of the data set. They are still not sensitive to the differences of the data even after normalization. According to the similarity system theory, an improved extent similarity method was proposed. The improved extent similarity is more sensitive to the differences of the data sets than correlation coefficient and cosine of the angle. And the character of the data sets needs not to be changed compared with log-transformation. The improved extent similarity can be used to evaluate the similarity of the chromatographic fingerprints of TCM.

  9. Investigations for chromatographic separation and determination of the rare earths and auxiliary group elements

    International Nuclear Information System (INIS)

    Post, K.

    1981-01-01

    Different method have been developed to quantitatively determine rare earth elements after their column chromatographic separation. The influence of the active solvents in the running systems diethyl ether/tetra hydrofuran (THF)/nitric acid (HNO 3 ) and diethyl ether/bis-(2-ethyl hexyl) phosphate (HDEHP)/HNO 3 was investigated on the column chromatographic separation of all rare earth elements is possible by the synergistic combination of the active running components THF and HDEHP. Further from product isotopes could also be separated using the running agents described here in investigations to separate fission product mixtures of irradiated uranium. (orig./HBR) [de

  10. NOAA Ship Bell M. Shimada Underway Meteorological Data, Quality Controlled

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NOAA Ship Bell M. Shimada Underway Meteorological Data (delayed ~10 days for quality control) are from the Shipboard Automated Meteorological and Oceanographic...

  11. NOAA Ship David Starr Jordan Underway Meteorological Data, Quality Controlled

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NOAA Ship David Starr Jordan Underway Meteorological Data (delayed ~10 days for quality control) are from the Shipboard Automated Meteorological and Oceanographic...

  12. NOAA Ship Henry B. Bigelow Underway Meteorological Data, Quality Controlled

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NOAA Ship Henry B. Bigelow Underway Meteorological Data (delayed ~10 days for quality control) are from the Shipboard Automated Meteorological and Oceanographic...

  13. NOAA Ship Oscar Elton Sette Underway Meteorological Data, Quality Controlled

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NOAA Ship Oscar Elton Sette Underway Meteorological Data (delayed ~10 days for quality control) are from the Shipboard Automated Meteorological and Oceanographic...

  14. Research Ship T. G. Thompson Underway Meteorological Data, Quality Controlled

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Research Ship T. G. Thompson Underway Meteorological Data (delayed ~10 days for quality control) are from the Shipboard Automated Meteorological and Oceanographic...

  15. Research Ship Laurence M. Gould Underway Meteorological Data, Quality Controlled

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Research Ship Laurence M. Gould Underway Meteorological Data (delayed ~10 days for quality control) are from the Shipboard Automated Meteorological and Oceanographic...

  16. System for separation of cortisol, 11-deoxycortisol, 17-hydroxyprogesterone and progesterone in a single chromatographic step and its application to radioimmunoassay

    Energy Technology Data Exchange (ETDEWEB)

    Cunningham, S K; McKenna, T J [St. Vincent' s Hospital, Dublin (Republic of Ireland). Dept. of Endocrinology

    1982-08-18

    A procedure for accurate, sensitive and highly specific measurement of cortisol, 11-deoxycortisol, 17-hydroxyprogesterone and progesterone is described. We have developed a chromatographic system whereby the steroids may be separated in a single passage over celite microcolumns. This permits the specific radioimmunoassay of the principal glucocorticoid in man and its ..delta..4-pregnene precursors and thus facilitates investigation of the physiological control and pathological disorders of glucocorticoid biosynthesis.

  17. Multiple chromatographic fingerprinting and its application to the quality control of herbal medicines

    Energy Technology Data Exchange (ETDEWEB)

    Fan Xiaohui [Pharmaceutical Informatics Institute, College of Pharmaceutical Sciences, Zhejiang University, Hangzhou 310027 (China); Cheng Yiyu [Pharmaceutical Informatics Institute, College of Pharmaceutical Sciences, Zhejiang University, Hangzhou 310027 (China)]. E-mail: chengyy@zju.edu.cn; Ye Zhengliang [Pharmaceutical Informatics Institute, College of Pharmaceutical Sciences, Zhejiang University, Hangzhou 310027 (China); Lin Ruichao [National Institute for the Control of Pharmaceutical and Biological Products, Beijing 100050 (China); Qian Zhongzhi [Committee of Chinese Pharmacopoeia, Beijing 100061 (China)

    2006-01-12

    Recently, chromatographic fingerprinting has become one of the most powerful approaches to quality control of herbal medicines. However, the performance of reported chromatographic fingerprinting constructed by single chromatogram sometimes turns out to be inadequate for complex herbal medicines, such as multi-herb botanical drug products. In this study, multiple chromatographic fingerprinting, which consists of more than one chromatographic fingerprint and represents the whole characteristics of chemical constitutions of the complex medicine, is proposed as a potential strategy in this complicated case. As a typical example, a binary chromatographic fingerprinting of 'Danshen Dropping Pill' (DSDP), the best-sold traditional Chinese medicine in China, was developed. First, two HPLC fingerprints that, respectively, represent chemical characteristics of depsides and saponins of DSDP were developed, which were used to construct binary chromatographic fingerprints of DSDP. Moreover, the authentication and validation of the binary fingerprints were performed. Then, a data-level information fusion method was employed to capture the chemical information encoded in two chromatographic fingerprints. Based on the fusion results, the lot-to-lot consistency and frauds can be determined either using similarity measure or by chemometrics approach. The application of binary chromatographic fingerprinting to consistency assessment and frauds detection of DSDP clearly demonstrated that the proposed method was a powerful approach to quality control of complex herbal medicines.

  18. Gas-chromatographic quantitative determination of argon in air samples, by elimination of oxigen

    International Nuclear Information System (INIS)

    Sofronie, E.

    1982-08-01

    A method of gas-chromatographic quantitative determination of argon in air samples, by elimination of oxygen, is presented. Experiments were carried out in a static system. Conditions for the application of the method in dynamic systems are specified. Sensibility of the method: 5 10 -4 cm 3 Ar per cm 3 of air. (author)

  19. Modeling chromatographic columns. Non-equilibrium packed-bed adsorption with non-linear adsorption isotherms

    NARCIS (Netherlands)

    Özdural, A.R.; Alkan, A.; Kerkhof, P.J.A.M.

    2004-01-01

    In this work a new mathematical model, based on non-equilibrium conditions, describing the dynamic adsorption of proteins in columns packed with spherical adsorbent particles is used to study the performance of chromatographic systems. Simulations of frontal chromatography, including axial

  20. Assessment of the chromatographic lipophilicity of eight cephalosporins on different stationary phases.

    Science.gov (United States)

    Dąbrowska, Monika; Starek, Małgorzata; Komsta, Łukasz; Szafrański, Przemysław; Stasiewicz-Urban, Anna; Opoka, Włodzimierz

    2017-04-01

    The retention behaviors were investigated for a series of eight cephalosporins in thin-layer chromatography (TLC) using stationary phases of RP-2, RP-8, RP-18, NH 2 , DIOL, and CN chemically bonded silica gel. Additionally, various binary mobile phases (water/methanol and water/acetone) were used in different volume proportions. The retention behavior of the analyzed molecules was defined by R M0 constant. In addition, reversed phase high performance liquid chromatography (RP-HPLC) was performed in lipophilicity studies by using immobilized artificial membrane (IAM) stationary phase. Obtained chromatographic data (R M0 and logk' IAM ) were correlated with the lipophilicity, expressed as values of the log calculated (logP calc ) and experimental (logP exp(shake-flask) ) partition coefficient. Principal component analysis (PCA) was applied in order to obtain an overview of similarity or dissimilarity among the analyzed compounds. Hierarchical cluster analysis (HCA) was performed to compare the separation characteristics of the applied stationary phases. This study was undertaken to identify the best chromatographic system and chromatographic data processing method to enable the prediction of logP values. A comprehensive chromatographic investigation into the retention of the analyzed cephalosporins revealed a similar behavior on RP-18, RP-8 and CN stationary phases. The weak correlations obtained between experimental and certain computed lipophilicity indices revealed that R M0 and PC1/RM are relevant lipophilicity parameters and the RP-8, CN and RP-18 plates are appropriate stationary phases for lipophilicity investigation, whereas computational approaches still cannot fully replace experimentation. Copyright © 2017 Elsevier B.V. All rights reserved.

  1. Automated-process gas-chromatograph system for use in accelerated corrosion testing of HTGR core-support posts

    International Nuclear Information System (INIS)

    Harper, R.E.; Herndon, P.G.

    1982-01-01

    An automated-process gas chromatograph is the heart of a gaseous-impurities-analysis system developed for the Oak Ridge National Laboratory Core Support Performance Test, at which graphite core-support posts for high-temperature gas-cooled fission reactors are being subjected to accelerated corrosion tests under tightly controlled conditions of atmosphere and temperature. Realistic estimation of in-core corrosion rates is critically dependent upon the accurate measurement of low concentrations of CO, CO 2 , CH 4 , H 2 , and O 2 in the predominantly helium atmosphere. In addition, the capital and labor investment associated with each test puts a premium upon the reliability of the analytical system, as excessive downtime or failure to obtain accurate data would result in unacceptable costs and schedule delays. After an extensive survey of available measurement techniques, gas chromatography was chosen for reasons of accuracy, flexibility, good-performance record, and cost

  2. Comparison of core-shell and totally porous ultra high performance liquid chromatographic stationary phases based on their selectivity towards alfuzosin compounds.

    Science.gov (United States)

    Szulfer, Jarosław; Plenis, Alina; Bączek, Tomasz

    2014-06-13

    This paper focuses on the application of a column classification system based on the Katholieke Universiteit Leuven for the characterization of physicochemical properties of core-shell and ultra-high performance liquid chromatographic stationary phases, followed by the verification of the reliability of the obtained column classification in pharmaceutical practice. In the study, 7 stationary phases produced in core-shell technology and 18 ultra-high performance liquid chromatographic columns were chromatographically tested, and ranking lists were built on the FKUL-values calculated against two selected reference columns. In the column performance test, an analysis of alfuzosin in the presence of related substances was carried out using the brands of the stationary phases with the highest ranking positions. Next, a system suitability test as described by the European Pharmacopoeia monograph was performed. Moreover, a study was also performed to achieve a purposeful shortening of the analysis time of the compounds of interest using the selected stationary phases. Finally, it was checked whether methods using core-shell and ultra-high performance liquid chromatographic columns can be an interesting alternative to the high-performance liquid chromatographic method for the analysis of alfuzosin in pharmaceutical practice. Copyright © 2014 Elsevier B.V. All rights reserved.

  3. Analyzing chromatographic data using multilevel modeling.

    Science.gov (United States)

    Wiczling, Paweł

    2018-06-01

    It is relatively easy to collect chromatographic measurements for a large number of analytes, especially with gradient chromatographic methods coupled with mass spectrometry detection. Such data often have a hierarchical or clustered structure. For example, analytes with similar hydrophobicity and dissociation constant tend to be more alike in their retention than a randomly chosen set of analytes. Multilevel models recognize the existence of such data structures by assigning a model for each parameter, with its parameters also estimated from data. In this work, a multilevel model is proposed to describe retention time data obtained from a series of wide linear organic modifier gradients of different gradient duration and different mobile phase pH for a large set of acids and bases. The multilevel model consists of (1) the same deterministic equation describing the relationship between retention time and analyte-specific and instrument-specific parameters, (2) covariance relationships relating various physicochemical properties of the analyte to chromatographically specific parameters through quantitative structure-retention relationship based equations, and (3) stochastic components of intra-analyte and interanalyte variability. The model was implemented in Stan, which provides full Bayesian inference for continuous-variable models through Markov chain Monte Carlo methods. Graphical abstract Relationships between log k and MeOH content for acidic, basic, and neutral compounds with different log P. CI credible interval, PSA polar surface area.

  4. Ion chromatographic determination of vanadium (4) and vanadium (5) in the form of EDTA complexes

    International Nuclear Information System (INIS)

    Komarova, T.V.; Obrezkov, O.N.; Shpigun, O.A.

    1991-01-01

    Ion chromatographic behaviour of V 4+ and V 5+ -EDTA complexes (1,2) and V 5+ -EDTA monoperoxo complexes (3) has been studied. The regularities of ion exchange are obeyed for 1 and 3 complexes. These complex anions are strongly retained on HIX-1 anion exchanger. The chromatographic characteristics of 2 change in time, therefore its determination is impossible under the conditions studied. A method has been developed of the simultaneous determination of V 4+ and V 5+ which is based on retarded formation of the V 5+ -EDTA monoperoxo complex in a system of V 4+ -EDTA - H 2 O 2

  5. Mixed-mode chromatographic matrices for the resolution of transfer ribonucleic acids

    NARCIS (Netherlands)

    Bischoff, Rainer; Mclaughlin, L.W.

    1984-01-01

    Modification of approximately 65% of the amine groups of an aminopropylsilyl bonded-phase silica high-performance liquid chromatographic anion exchanger (APS-Hypersil) with organic acids containing n-alkyl moieties of different chain lengths, results in mixed mode chromatographic matrices of varying

  6. Radioimmunoassay of methaqualone in human urine compared with chromatographic methods

    International Nuclear Information System (INIS)

    Mule, S.J.; Kogan, M.; Jukofsky, D.

    1978-01-01

    The 125 I-radioimmunoassay for methaqualone in human urine was evaluated by a comparison with newly modified gas-liquid chromatographic and thin-layer chromatographic methods. The statistically significant sensitivity value for the radioimmunoassay was at 2 μg of methaqualone per liter of urine. The coefficient of variation was 2.88 -+ 0.16% intraassay. There was cross-reactivity only with metabolites of methaqualone, 4'-hydroxymethaqualone being twice as sensitively measured as methaqualone. There was complete agreement between results by radioimmunoassay and by gas-liquid chromatography in 96.7% of the samples analyzed. Only 1.2% of the radioimmunoassay values were false positives, and 2.1% false negatives (phi = 0.8917, P < 0.001). Comparisons between the thin-layer chromatographic data and the gas--liquid chromatographic or radioimmunoassay data showed less agreement because of the 50- to 200-fold higher sensitivity of the latter techniques. Gas--liquid chromatography therefore appears to represent the best reference method for the evaluation of the radioimmunoassay, which appears to be a very sensitive and reliable technique for detecting methaqualone and its metabolites in human urine

  7. The combination of the liquid chromatograph with the nuclear magnetic resonance spectrometer

    International Nuclear Information System (INIS)

    Scott, R.P.W.

    1986-01-01

    The association of the liquid chromatograph with the NMR spectrometer would be a very powerful analytical system for the separation and identification of unknown mixtures. There are, however, some serious difficulties involved with the association of these two techniques. The historical development of NMR chromatography is outlined and some problems are discussed. (Auth.)

  8. Chromatographic and biological aspects of organomercurials

    Energy Technology Data Exchange (ETDEWEB)

    Fishbein, L

    1970-01-01

    A thorough review on the biological and chromatographic aspects of methylmercury, phenylmercurials, and miscellaneous organomercurials is presented. Areas covered include ecology, epidemiology, paper chromatography, thin-layer chromatography, gas chromatography, metabolism and toxicity, and environmental degradation. 183 references.

  9. Environmental Technology Verification Report. Field Portable Gas Chromatograph/Mass Spectrometer. Viking Instruments Corporation SpectraTrak (Trademark) 672

    National Research Council Canada - National Science Library

    Enfield, Wayne

    1997-01-01

    .... This self-contained, field transportable system, whose design has been adapted from laboratory technology, uses a contained, chromatographic column and accompanying mass spectrometer to provide...

  10. Chromatographic methods

    International Nuclear Information System (INIS)

    Marhol, M.; Stary, J.

    1975-01-01

    The characteristics are given of chromatographic separation and the methods are listed. Methods and data on materials used in partition, adsorption, precipitation and ion exchange chromatography are listed and conditions are described under which ion partition takes place. Special attention is devoted to ion exchange chromatography where tables are given to show the course of values of the partition coefficients of different ions in dependence on the concentration of agents and the course of equilibrium sorptions on different materials in dependence on the solution pH. A theoretical analysis is given and the properties of the most widely used ion exchangers are listed. Experimental conditions and apparatus used for each type of chromatography are listed. (L.K.)

  11. A Quantitative Gas Chromatographic Ethanol Determination.

    Science.gov (United States)

    Leary, James J.

    1983-01-01

    Describes a gas chromatographic experiment for the quantitative determination of volume percent ethanol in water ethanol solutions. Background information, procedures, and typical results are included. Accuracy and precision of results are both on the order of two percent. (JN)

  12. Improved stochastic resonance algorithm for enhancement of signal-to-noise ratio of high-performance liquid chromatographic signal

    International Nuclear Information System (INIS)

    Xie Shaofei; Xiang Bingren; Deng Haishan; Xiang Suyun; Lu Jun

    2007-01-01

    Based on the theory of stochastic resonance, an improved stochastic resonance algorithm with a new criterion for optimizing system parameters to enhance signal-to-noise ratio (SNR) of HPLC/UV chromatographic signal for trace analysis was presented in this study. Compared with the conventional criterion in stochastic resonance, the proposed one can ensure satisfactory SNR as well as good peak shape of chromatographic peak in output signal. Application of the criterion to experimental weak signals of HPLC/UV was investigated and the results showed an excellent quantitative relationship between different concentrations and responses

  13. Development and validation of micellar liquid chromatographic methods for the determination of antibiotics in different matrixes.

    Science.gov (United States)

    Rambla-Alegre, Maria; Esteve-Romero, Josep; Carda-Broch, Samuel

    2011-01-01

    Antibiotics are the most important bioactive and chemotherapeutic compounds to be produced by microbiological synthesis, and they have proved their worth in a variety of fields, such as medicinal chemistry, agriculture, and the food industry. Interest in antibiotics has grown in parallel with an increasingly high degree of productivity in the field of analytical applications. Therefore, it is necessary to develop chromatographic procedures capable of determining various drugs simultaneously in the shortest possible time. Micellar liquid chromatography (MLC) is an RP-HPLC technique that offers advantages over conventional HPLC as far as sample preparation, selectivity, and versatility are concerned. Its main advantage is that samples can be injected directly into the chromatographic system with no previous preparation step. This paper mainly focuses on the results of the authors' own recent research and reports the chromatographic conditions for determination of various antibiotics (penicillins, quinolones, and sulfonamides) in different matrixes (pharmaceuticals, biological fluids, and food). The work of other authors on MLC-based antibiotic determination has been included.

  14. Liquid chromatographic analysis of phenobarbitone, ethosuximide ...

    African Journals Online (AJOL)

    A liquid chromatographic method for the simultaneous assay of four anticonvulsant drugs, phenobarbitone, ethosuximide, phenytoin and carbamazepine on a polystyrene-divinyl benzene column is described. The method was developed by the systematic study of different types of co-polymer materials, type and ...

  15. Chromatographic Separations of Enantiomers and Underivatized Oligosaccharides

    Energy Technology Data Exchange (ETDEWEB)

    Liu, Ying [Iowa State Univ., Ames, IA (United States)

    2004-01-01

    My graduate research has focused on separation science and bioanalytical analysis, which emphasized in method development. It includes three major areas: enantiomeric separations using high performance liquid chromatography (HPLC), Super/subcritical fluid chromatography (SFC), and capillary electrophoresis (CE); drug-protein binding behavior studies using CE; and carbohydrate analysis using liquid chromatograph-electrospray ionization mass spectrometry (LC-ESI-MS). Enantiomeric separations continue to be extremely important in the pharmaceutical industry. An in-depth evaluation of the enantiomeric separation capabilities of macrocyclic glycopeptides CSPs with SFC mobile phases was investigated using a set of over 100 chiral compounds. It was found that the macrocyclic based CSPs were able to separate enantiomers of various compounds with different polarities and functionalities. Seventy percent of all separations were achieved in less than 4 min due to the high flow rate (4.0 ml/min) that can be used in SFC. Drug-protein binding is an important process in determining the activity and fate of a drug once it enters the body. Two drug/protein systems have been studied using frontal analysis CE method. More sensitive fluorescence detection was introduced in this assay, which overcame the problem of low sensitivity that is common when using UV detection for drug-protein studies. In addition, the first usage of an argon ion laser with 257 nm beam coupled with CCD camera as a frontal analysis detection method enabled the simultaneous observation of drug fluorescence as well as the protein fluorescence. LC-ESI-MS was used for the separation and characterization of underivatized oligosaccharide mixtures. With the limits of detection as low as 50 picograms, all individual components of oligosaccharide mixtures (up to 11 glucose-units long) were baseline resolved on a Cyclobond I 2000 column and detected using ESI-MS. This system is characterized by high chromatographic

  16. Chromatographic Separations of Enantiomers and Underivatized Oligosaccharides

    International Nuclear Information System (INIS)

    Ying Liu

    2004-01-01

    My graduate research has focused on separation science and bioanalytical analysis, which emphasized in method development. It includes three major areas: enantiomeric separations using high performance liquid chromatography (HPLC), Super/subcritical fluid chromatography (SFC), and capillary electrophoresis (CE); drug-protein binding behavior studies using CE; and carbohydrate analysis using liquid chromatograph-electrospray ionization mass spectrometry (LC-ESI-MS). Enantiomeric separations continue to be extremely important in the pharmaceutical industry. An in-depth evaluation of the enantiomeric separation capabilities of macrocyclic glycopeptides CSPs with SFC mobile phases was investigated using a set of over 100 chiral compounds. It was found that the macrocyclic based CSPs were able to separate enantiomers of various compounds with different polarities and functionalities. Seventy percent of all separations were achieved in less than 4 min due to the high flow rate (4.0 ml/min) that can be used in SFC. Drug-protein binding is an important process in determining the activity and fate of a drug once it enters the body. Two drug/protein systems have been studied using frontal analysis CE method. More sensitive fluorescence detection was introduced in this assay, which overcame the problem of low sensitivity that is common when using UV detection for drug-protein studies. In addition, the first usage of an argon ion laser with 257 nm beam coupled with CCD camera as a frontal analysis detection method enabled the simultaneous observation of drug fluorescence as well as the protein fluorescence. LC-ESI-MS was used for the separation and characterization of underivatized oligosaccharide mixtures. With the limits of detection as low as 50 picograms, all individual components of oligosaccharide mixtures (up to 11 glucose-units long) were baseline resolved on a Cyclobond I 2000 column and detected using ESI-MS. This system is characterized by high chromatographic

  17. Multiple-channel ultra-violet absorbance detector for two-dimensional chromatographic separations.

    Science.gov (United States)

    Lynch, Kyle B; Yang, Yu; Ren, Jiangtao; Liu, Shaorong

    2018-05-01

    In recent years, much research has gone into developing online comprehensive two-dimensional liquid chromatographic systems allowing for high peak capacities in comparable separation times to that of one-dimensional liquid chromatographic systems. However, the speed requirements in the second dimension (2nd-D) still remain one challenge for complex biological samples due to the current configuration of two column/two detector systems. Utilization of multiple 2nd-D columns can mitigate this challenge. To adapt this approach, we need a multiple channel detector. Here we develop a versatile multichannel ultraviolet (UV) light absorbance detector that is capable of simultaneously monitoring separations in 12 columns. The detector consists of a deuterium lighthouse, a flow cell assembly (a 13-channel flow cell fitted with a 13-photodiode-detection system), and a data acquisition and monitoring terminal. Through the use of a custom high optical quality furcated fiber to improve light transmission, precise machining of a flow cell to reduce background stray light through precision alignment, and sensitive electronic circuitry to reduce electronic noise through an active low pass filter, the background noise level is measured in the tens of µAU. We obtain a linear dynamic range of close to three orders of magnitude. Compared to a commercialized multichannel UV light absorbance detector like the Waters 2488 UV/Vis, our device provides an increase in channel detection while residing within the same noise region and linear range. Copyright © 2018 Elsevier B.V. All rights reserved.

  18. High Performance Liquid Chromatographic Analysis of Phytoplankton Pigments Using a C16-Amide Column

    Science.gov (United States)

    A reverse-phase high performance liquid chromatographic (RP-HPLC) method was developed to analyze in a single run, most polar and non-polar chlorophylls and carotenoids from marine phytoplankton. The method is based on a RP-C16-Amide column and a ternary gradient system consistin...

  19. On-line gas chromatographic analysis of airborne particles

    Science.gov (United States)

    Hering, Susanne V [Berkeley, CA; Goldstein, Allen H [Orinda, CA

    2012-01-03

    A method and apparatus for the in-situ, chemical analysis of an aerosol. The method may include the steps of: collecting an aerosol; thermally desorbing the aerosol into a carrier gas to provide desorbed aerosol material; transporting the desorbed aerosol material onto the head of a gas chromatography column; analyzing the aerosol material using a gas chromatograph, and quantizing the aerosol material as it evolves from the gas chromatography column. The apparatus includes a collection and thermal desorption cell, a gas chromatograph including a gas chromatography column, heated transport lines coupling the cell and the column; and a quantization detector for aerosol material evolving from the gas chromatography column.

  20. Liquid chromatographic-mass spectrometric method for ...

    African Journals Online (AJOL)

    Tropical Journal of Pharmaceutical Research ... Purpose: To develop and validate a simple, efficient and reliable Liquid chromatographic-mass spectrometric (LC-MS/MS) method for the quantitative determination of two dermatological drugs, ... By Country · List All Titles · Free To Read Titles This Journal is Open Access.

  1. Analysis and chromatographic purification of eicosanoids multiply labeled by tritium

    International Nuclear Information System (INIS)

    Shevchenko, V.P.; Nagaev, I.Yu.; Myasoedov, N.F.

    1989-01-01

    We show the possibility of analysis and chromatographic purification of eicosanoids triply labeled by tritium. The described methods allow us to isolate chromatographically pure products obtained by selective hydrogenatin, chemical, and enzyme methods, with radiochemical purity at least 95-97%. The following methods are used to analyze the reaction mixtures and to isolate the tritium-labeled eicosanoids: gas-liquid chromatography, high-efficiency liquid chromatography, and thin-layer chromatography on supports impregnated with silver nitrate

  2. Coupling spectroscopic and chromatographic techniques for evaluation of the depositional history of hydrocarbons in a subtropical estuary

    International Nuclear Information System (INIS)

    Martins, César C.; Doumer, Marta E.; Gallice, Wellington C.; Dauner, Ana Lúcia L.; Cabral, Ana Caroline; Cardoso, Fernanda D.

    2015-01-01

    Spectroscopic and chromatographic techniques can be used together to evaluate hydrocarbon inputs to coastal environments such as the Paranaguá estuarine system (PES), located in the SW Atlantic, Brazil. Historical inputs of aliphatic hydrocarbons (AHs) and polycyclic aromatic hydrocarbons (PAHs) were analyzed using two sediment cores from the PES. The AHs were related to the presence of biogenic organic matter and degraded oil residues. The PAHs were associated with mixed sources. The highest hydrocarbon concentrations were related to oil spills, while relatively low levels could be attributed to the decrease in oil usage during the global oil crisis. The results of electron paramagnetic resonance were in agreement with the absolute AHs and PAHs concentrations measured by chromatographic techniques, while near-infrared spectroscopy results were consistent with unresolved complex mixture (UCM)/total n-alkanes ratios. These findings suggest that the use of a combination of techniques can increase the accuracy of assessment of contamination in sediments. - Highlights: • Historical inputs of hydrocarbons in a subtropical estuary were evaluated. • Spectroscopic and chromatographic methods were used in combination. • High hydrocarbon concentrations were related to anthropogenic activities. • Low hydrocarbon levels could be explained by the 1970s global oil crisis. - Spectroscopic and chromatographic techniques could be used together to evaluate hydrocarbon inputs to coastal environments

  3. Chromatographic separation of europium and gadolinum mixtures by ethylenediaminedisuccinic acid

    International Nuclear Information System (INIS)

    Kolleganov, M.Yu.; Nazarov, P.P.; Martynenko, L.I.; Mtrofanova, N.D.; Spitsyn, V.I.

    1985-01-01

    Comparative investigation of chromatographic separation of impurities of Eu and Gd micro- and macroquantities by means of ethylenediaminedisuccinic (EDDS) and ethylene-diaminetetraacetic (EDTA) acids is performed. It is shown that EDTA is a sufficiently effective agent for separation of this pair of elements. The values of EU and Gd separation coefficients obtained in experiments with RE microquantities are not realized at Eu-Gd, macroquantities separation which probably is connected with the influence of polymerization processes in the systems containing RE and EDDS complexes

  4. Isotope separations using chromatographic methods

    International Nuclear Information System (INIS)

    Leseticky, L.

    1985-01-01

    A survey is given of chromatographic separations of compounds only differing in isotope composition. Isotope effects on physical properties which allow chromatographic separation (vapour tension, adsorption heat, partition coefficient) are very small, with the exception of the simplest molecules. Therefore, separation factors only assume the value of several per cent. From this ensues the necessity of using columns which are specially and very carefully prepared and have a separation efficiency of the order of 10 4 theoretical plates. Briefly discussed is liquid chromatography on ion exchangers which with a varied degree of success was used for separating simple inorganic compounds or ions. Ion exchange chromatography of amino acids labelled with tritium, and chromatography of tritium labelled steroids also provided only a certain degree of separation. A detailed analysis is presented of gas chromatography separation of various deuterium and tritium labelled low-molecular compounds, to which a number of studies has been devoted in the literature. Very promising is the method of complexation gas chromatography based on the reversible formation of a complex of the ligand (the compound being separated) and the compound of the (transition) metal as the steady-state phase. (author)

  5. Detection system for a gas chromatograph. [. cap alpha. -methylnaphthalene,. beta. -methylnapthalene

    Science.gov (United States)

    Hayes, J.M.; Small, G.J.

    1982-04-26

    A method and apparatus are described for the quantitative analysis of vaporizable compounds, and in particular of polycyclic aromatic hydrocarbons which may be induced to fluoresce. The sample to be analyzed is injected into a gas chromatography column and is eluted through a narrow orifice into a vacuum chamber. The free expansion of the eluted sample into the vacuum chamber creates a supersonic molecular beam in which the sample molecules are cooled to the extent that the excited vibrational and rotational levels are substantially depopulated. The cooled molecules, when induced to fluoresce by laser excitation, give greatly simplified spectra suitable for analytical purposes. The laser induced fluorimetry provides great selectivity, and the gas chromatograph provides quantitative transfer of the sample to the molecular beam. 3 figures, 2 tables.

  6. Chromatographic monitoring procedures in laboratory practice

    Energy Technology Data Exchange (ETDEWEB)

    Kaplina, E G; Belova, O I; Lasunina, N A

    1976-01-01

    The Moscow Coke and Chemical Works consist of three plants in combination, viz., the coking plant, the synthetic ammonia plant using coke-oven-gas hydrogen and the oxygen plant. The plant requirements include daily analyses not only of the coke-oven gas but also of a rich gas and an ethylene fraction. The analyses are carried out in VTI-2 apparatus. The analytical data are used to calculate the calorific values and densities of the gases. The time requirements are very considerable and the laboratory has long been engaged in developing and introducing chromatographic procedures for the major constituents of coke-oven gas, rich gas and ethylene fraction. The procedure developed for the coke-oven and rich gases uses two parallel columns, one packed with molecular sieves and the other with grade KSM silica gel. Hydrogen was determined with argon as the carrier gas, and all other constituents with helium. The procedure was time-consuming and complicated. An attempt was made to separate the gases in an LKhM-7a chromatograph with a programme-controlled 50 to 250/sup 0/C heating cycle, but the procedure still had a number of serious defects and could not be recommended for regular quality control. The final variant involved two parallel columns and a procedure based on that in GOST 14920 (''Dry gas. Proximate analysis''). The chromatograph was a type KhL-69 with a 6-way cock in the gas line so that each of the columns could be brought on stream in succession. The analytical column packings were zeolite (in a 2 m column) and diatomaceous brick with 25% n-hexadecane (in a 6 m column).

  7. Hydrocarbon Fuel Thermal Performance Modeling based on Systematic Measurement and Comprehensive Chromatographic Analysis

    Science.gov (United States)

    2016-07-31

    distribution unlimited Hydrocarbon Fuel Thermal Performance Modeling based on Systematic Measurement and Comprehensive Chromatographic Analysis Matthew...vital importance for hydrocarbon -fueled propulsion systems: fuel thermal performance as indicated by physical and chemical effects of cooling passage... analysis . The selection and acquisition of a set of chemically diverse fuels is pivotal for a successful outcome since test method validation and

  8. Use of coextraction and suppression of extraction in extraction-chromatographic separation of elements

    International Nuclear Information System (INIS)

    Karandashev, V.K.; Kuznetsov, R.A.; Grazhulene, S.S.; Usmanova, M.M.

    1988-01-01

    TBP, solutions of hydrobromic acid, indium and polytetrafluoroethylene powder, carrier for TBP, were used to study the effects of coextraction and extraction suppression on extraction-chromatographic behaviour of microamounts of elements in the presence of macroamounts of other elements. Possibility of using these effects under extraction-chromatographic element separation were considered. A new method for extraction-chromatographic separation of scandium microamounts from the mixture of large amount of elements (Y, Cd, Ce, Eu, Lu, Hf, Ta, W, Np and other) was suggested. 15 refs.; 3 figs

  9. High-performance liquid chromatographic method for guanylhydrazone compounds.

    Science.gov (United States)

    Cerami, C; Zhang, X; Ulrich, P; Bianchi, M; Tracey, K J; Berger, B J

    1996-01-12

    A high-performance liquid chromatographic method has been developed for a series of aromatic guanylhydrazones that have demonstrated therapeutic potential as anti-inflammatory agents. The compounds were separated using octadecyl or diisopropyloctyl reversed-phase columns, with an acetonitrile gradient in water containing heptane sulfonate, tetramethylammonium chloride, and phosphoric acid. The method was used to reliably quantify levels of analyte as low as 785 ng/ml, and the detector response was linear to at least 50 micrograms/ml using a 100 microliters injection volume. The assay system was used to determine the basic pharmacokinetics of a lead compound, CNI-1493, from serum concentrations following a single intravenous injection in rats.

  10. Ion Chromatographic Analyses of Sea Waters, Brines and Related Samples

    OpenAIRE

    Nataša Gros

    2013-01-01

    This review focuses on the ion chromatographic methods for the analyses of natural waters with high ionic strength. At the beginning a natural diversity in ionic composition of waters is highlighted and terminology clarified. In continuation a brief overview of other review articles of potential interest is given. A review of ion chromatographic methods is organized in four sections. The first section comprises articles focused on the determination of ionic composition of water samples as com...

  11. Automation of an ion chromatograph for precipitation analysis with computerized data reduction

    Science.gov (United States)

    Hedley, Arthur G.; Fishman, Marvin J.

    1982-01-01

    Interconnection of an ion chromatograph, an autosampler, and a computing integrator to form an analytical system for simultaneous determination of fluoride, chloride, orthophosphate, bromide, nitrate, and sulfate in precipitation samples is described. Computer programs provided with the integrator are modified to implement ionchromatographic data reduction and data storage. The liquid-flow scheme for the ion chromatograph is changed by addition of a second suppressor column for greater analytical capacity. An additional vave enables selection of either suppressor column for analysis, as the other column is regenerated and stabilized with concentrated eluent.Minimum limits of detection and quantitation for each anion are calculated; these limits are a function of suppressor exhaustion. Precision for replicate analyses of six precipitation samples for fluoride, chloride, orthophosphate, nitrate, and sulfate ranged from 0.003 to 0.027 milligrams per liter. To determine accuracy of results, the same samples were spiked with known concentrations of the above mentioned anions. Average recovery was 108 percent.

  12. Chromatographic decontamination of medium-activity waste concentrates

    International Nuclear Information System (INIS)

    Faubel, W.; Menzler, P.M.; Sameh, A.A.

    1988-01-01

    The chromatographic decontamination of a MAW concentrate was carried out in a laboratory plant in 1-l-batches in the following way: In order to purify the nitric MAW concentrate from its solid and organic contamination products, it is passed through a filter and an absorber (SM7) for organic species. Subsequently the purified solution runs on-line through all following columns. First the main activity carrier cesium ( 137 Cs, 134 Cs) is transferred to ammonium molybdate phosphate (AMP-1) by means of a newly developed fluidized bed process. In the further course, 125 Sb is separated on metal oxides (Sb 2 O 5 , MnO 2 ) and the three-valued actinides/lanthanides on an extraction-chromatographic CMPO column. Finally the remaining 106 Ru and 60 Co activities are separated on dimethylglyoximes (DMG) coated on active carbon. (orig./RB) [de

  13. Chromatographic quality control procedures for /sup 99m/Tc-diagnostic agents

    International Nuclear Information System (INIS)

    Marinelli, M.; Pozzato, R.; Garuti, P.; Zucchini, G.L.

    1986-01-01

    The purpose of this work was to experiment simple and rapid chromatographic systems, based on paper and thin-layer techniques, to test the radiochemical purity of some common /sup 99m/Tc diagnostic agents, and select those systems able to prevent the anomalies due to oxidation and artifact production. The agents were examined under conditions which usually bring about the above mentioned anomalies, then the results were compared with those obtained under controlled conditions. Quali- and quantitative detection of the activity present on the chromatograms was carried out using the equipment available in nuclear medicine departments

  14. Protein selectivity with immobilized metal ion-tacn sorbents: chromatographic studies with human serum proteins and several other globular proteins.

    Science.gov (United States)

    Jiang, W; Graham, B; Spiccia, L; Hearn, M T

    1998-01-01

    The chromatographic selectivity of the immobilized chelate system, 1,4,7-triazocyclononane (tacn), complexed with the borderline metal ions Cu2+, Cr3+, Mn2+, Co2+, Zn2+, and Ni2+ has been investigated with hen egg white lysozyme, horse heart cytochrome c, and horse skeletal muscle myoglobin, as well as proteins present in partially fractionated preparations of human plasma. The effects of ionic strength and pH of the loading and elution buffers on protein selectivities of these new immobilized metal ion affinity chromatographic (IMAC) systems have been examined. The results confirm that immobilized Mn;pl-tacn sorbents exhibit a novel type of IMAC behavior with proteins. In particular, the chromatographic properties of these immobilized M(n+)-tacn ligand systems were significantly different compared to the IMAC behavior observed with other types of immobilized tri- and tetradentate chelating ligands, such as iminodiacetic acid, O-phosphoserine, or nitrilotriacetic acid, when complexed with borderline metal ions. The experimental results have consequently been evaluated in terms of the additional contributions to the interactive processes mediated by effects other than solely the conventional lone pair Lewis soft acid-Lewis soft base coordination interactions, typically found for the IMAC of proteins with borderline and soft metal ions, such as Cu2+ or Ni2+.

  15. Research on technology of online gas chromatograph for SF6 decomposition products

    Science.gov (United States)

    Li, L.; Fan, X. P.; Zhou, Y. Y.; Tang, N.; Zou, Z. L.; Liu, M. Z.; Huang, G. J.

    2017-12-01

    Sulfur hexafluoride (SF6) decomposition products were qualitatively and quantitatively analyzed by several gas chromatographs in the laboratory. Test conditions and methods were selected and optimized to minimize and eliminate the SF6’ influences on detection of other trace components. The effective separation and detection of selected characteristic gases were achieved. And by comparison among different types of gas chromatograph, it was found that GPTR-S101 can effectively separate and detect SF6 decomposition products and has best the best detection limit and sensitivity. On the basis of GPTR-S101, online gas chromatograph for SF6decomposition products (GPTR-S201) was developed. It lays the foundation for further online monitoring and diagnosis of SF6.

  16. Chromatographic separation of radioactive noble gases from xenon

    Science.gov (United States)

    Akerib, D. S.; Araújo, H. M.; Bai, X.; Bailey, A. J.; Balajthy, J.; Beltrame, P.; Bernard, E. P.; Bernstein, A.; Biesiadzinski, T. P.; Boulton, E. M.; Bramante, R.; Cahn, S. B.; Carmona-Benitez, M. C.; Chan, C.; Chiller, A. A.; Chiller, C.; Coffey, T.; Currie, A.; Cutter, J. E.; Davison, T. J. R.; Dobi, A.; Dobson, J. E. Y.; Druszkiewicz, E.; Edwards, B. N.; Faham, C. H.; Fiorucci, S.; Gaitskell, R. J.; Gehman, V. M.; Ghag, C.; Gibson, K. R.; Gilchriese, M. G. D.; Hall, C. R.; Hanhardt, M.; Haselschwardt, S. J.; Hertel, S. A.; Hogan, D. P.; Horn, M.; Huang, D. Q.; Ignarra, C. M.; Ihm, M.; Jacobsen, R. G.; Ji, W.; Kamdin, K.; Kazkaz, K.; Khaitan, D.; Knoche, R.; Larsen, N. A.; Lee, C.; Lenardo, B. G.; Lesko, K. T.; Lindote, A.; Lopes, M. I.; Manalaysay, A.; Mannino, R. L.; Marzioni, M. F.; McKinsey, D. N.; Mei, D.-M.; Mock, J.; Moongweluwan, M.; Morad, J. A.; Murphy, A. St. J.; Nehrkorn, C.; Nelson, H. N.; Neves, F.; O'Sullivan, K.; Oliver-Mallory, K. C.; Palladino, K. J.; Pease, E. K.; Pech, K.; Phelps, P.; Reichhart, L.; Rhyne, C.; Shaw, S.; Shutt, T. A.; Silva, C.; Solovov, V. N.; Sorensen, P.; Stephenson, S.; Sumner, T. J.; Szydagis, M.; Taylor, D. J.; Taylor, W.; Tennyson, B. P.; Terman, P. A.; Tiedt, D. R.; To, W. H.; Tripathi, M.; Tvrznikova, L.; Uvarov, S.; Verbus, J. R.; Webb, R. C.; White, J. T.; Whitis, T. J.; Witherell, M. S.; Wolfs, F. L. H.; Yazdani, K.; Young, S. K.; Zhang, C.

    2018-01-01

    The Large Underground Xenon (LUX) experiment operates at the Sanford Underground Research Facility to detect nuclear recoils from the hypothetical Weakly Interacting Massive Particles (WIMPs) on a liquid xenon target. Liquid xenon typically contains trace amounts of the noble radioactive isotopes 85Kr and 39Ar that are not removed by the in situ gas purification system. The decays of these isotopes at concentrations typical of research-grade xenon would be a dominant background for a WIMP search experiment. To remove these impurities from the liquid xenon, a chromatographic separation system based on adsorption on activated charcoal was built. 400 kg of xenon was processed, reducing the average concentration of krypton from 130 ppb to 3.5 ppt as measured by a cold-trap assisted mass spectroscopy system. A 50 kg batch spiked to 0.001 g/g of krypton was processed twice and reduced to an upper limit of 0.2 ppt.

  17. High-pressure liquid chromatographic assay of Bay n 7133 in human serum.

    OpenAIRE

    Fasching, C E; Hughes, C E; Hector, R F; Peterson, L R

    1984-01-01

    A high-pressure liquid chromatographic method that includes a Sep-Pak (Waters Associates, Inc., Milford , Mass.) preparation of human serum was employed for the quantitative assay of Bay n 7133. Drug levels of 0.1 to 20 micrograms/ml could be detected. No interference from amphotericin B was found in the chromatographic analysis of Bay n 7133.

  18. Pyrolysis gas chromatographic atomic emission detection for sediments, coals and other petrochemical precursors

    Energy Technology Data Exchange (ETDEWEB)

    Seeley, J.A.; Zeng, Y.D.; Uden, P.C.; Eglinton, T.I.; Ericson, I. (Massachusetts University, Amherst, MA (USA). Dept. of Chemistry)

    1992-09-01

    On-line flash pyrolysis coupled to a capillary gas chromatograph for the characterization of marine sediments, coals and other heterogeneous solid samples is described. A helium microwave-induced plasma is used for chromatographic detection by atomic emission spectrometry. Simultaneous multi-element detection is achieved with a photodiode array detector. The optical path of the gas chromatographic atomic emission detector is purged with helium, allowing simultaneous, sensitive detection of atomic emission from sulfur 181 nm, phosphorous 186 nm, arsenic 189 nm, selenium 196 nm and carbon 193 nm. Several sediment and coal samples have been analysed for their carbon, nitrogen, sulfur, oxygen, phosphorous, arsenic and selenium content. Qualitative information indicating the occurrence and distribution of these elements in the samples can be used to gauge the relative stage of diagenetic evolution of the samples and provide information on their depositional environment. In some instances the chromatographic behaviour of the compounds produced upon pyrolysis is improved through on-line alkylation. This on-line derivatization is achieved by adding liquid reagents to the pyrolysis probe or by adding liquid reagents to the pyrolysis probe or by adding solid reagents either to the solid sample or by packing the reagent in the injection port of the chromatograph.

  19. Chromatographic method of measurement of helium concentration in underground waters for dating in hydrological questions

    International Nuclear Information System (INIS)

    Najman, J.

    2008-04-01

    Research methods which use natural environmental indicators are widely applied in hydrology. Different concentrations of indicators and their isotopic components in ground waters allow to determine the genesis of waters and are valuable source of information about the water flow dynamics. One of the significant indicator is helium. The concentration of 4 He (helium) in ground water is a fine indicator in water dating in a range from a hundreds to millions of years (Aeschbach-Hertig i in., 1999; Andrews i in., 1989; Castro i in., 2000; Zuber i in., 2007). 4 He is also used for dating young waters of age about 10 years (Solomon i in., 1996). Thesis consist the description of elaborated in IFJ PAN in Krakow chromatographic measurement method of helium concentration in ground waters in aim of dating. Chapter 1 contain short introduction about ground water dating and chapter 2 description of helium property and chosen applications of helium for example in technology and earthquake predictions. Helium sources in ground waters are described in chapter 3. Helium concentration in water after infiltration (originated from atmosphere) to the ground water system depends mainly on the helium concentration coming from the equilibration with the atmosphere increased by additional concentration from '' excess air ''. With the increasing resistance time of ground water during the flow, radiogenic, non-atmospheric component of helium dissolves also in water. In chapter 4 two measurement methods of helium concentration in ground waters were introduced: mass spectrometric and gas chromatographic method. Detailed description of elaborated chromatographic measurement method of helium concentration in ground water contain chapter 5. To verify developed method the concentration of helium in ground waters from the regions of Krakow and Busko Zdroj were measured. For this waters the concentrations of helium are known from the earlier mass spectrometric measurements. The results of

  20. Chromatographic background drift correction coupled with parallel factor analysis to resolve coelution problems in three-dimensional chromatographic data: quantification of eleven antibiotics in tap water samples by high-performance liquid chromatography coupled with a diode array detector.

    Science.gov (United States)

    Yu, Yong-Jie; Wu, Hai-Long; Fu, Hai-Yan; Zhao, Juan; Li, Yuan-Na; Li, Shu-Fang; Kang, Chao; Yu, Ru-Qin

    2013-08-09

    Chromatographic background drift correction has been an important field of research in chromatographic analysis. In the present work, orthogonal spectral space projection for background drift correction of three-dimensional chromatographic data was described in detail and combined with parallel factor analysis (PARAFAC) to resolve overlapped chromatographic peaks and obtain the second-order advantage. This strategy was verified by simulated chromatographic data and afforded significant improvement in quantitative results. Finally, this strategy was successfully utilized to quantify eleven antibiotics in tap water samples. Compared with the traditional methodology of introducing excessive factors for the PARAFAC model to eliminate the effect of background drift, clear improvement in the quantitative performance of PARAFAC was observed after background drift correction by orthogonal spectral space projection. Copyright © 2013 Elsevier B.V. All rights reserved.

  1. Industrial scale chromatographic separation of valuable compounds from biomass hydrolysates and side streams

    Energy Technology Data Exchange (ETDEWEB)

    Saari, P.

    2011-06-15

    Carbohydrates are composed of a number of various monosaccharides, glucose being the most abundant. Some of the monosaccharides are valuable compounds used in the food and pharmaceutical industries. They can be separated from biomass hydrolysates e.g. by chromatographic methods. In this thesis, chromatographic separation of valuable compounds using ion exchange resins was studied on an industrial scale. Of special interest were rare monosaccharides in biomass hydrolysates. A novel chromatographic separation process was developed for fucose, starting from pre-processed spent sulfite liquor. The core of the process consists of three chromatographic separations with different types of ion exchange resins. Chromatographic separation of galactose was tested with three biomass hydrolysates; lactose, gum arabic and hemicellulose hydrolysates. It was demonstrated that also galactose can be separated from complex carbohydrate mixtures. A recovery process for arabinose from citrus pectin liquid residual and for mannose from wood pulp hydrolysate were also developed and experimentally verified. In addition to monosaccharides, chromatographic separation of glycinebetaine from vinasse was examined with a hydrogen form weak acid cation exchange resin. The separation involves untypical peak formation depending, for example, on the pH and the cation composition. The retention mechanism was found to be hydrogen bonding between glycinebetaine and the resin. In the experimental part, all four resin types - strong acid cation, strong base anion, weak acid cation and weak base anion exchange resins - were used. In addition, adsorption equilibria data of seven monosaccharides and sucrose were measured with the resins in sodium and sulfate forms because such data have been lacking. It was found out that the isotherms of all sugars were linear under industrial conditions. A systematic method for conceptual process design and sequencing of chromatographic separation steps were developed

  2. Chromatographic separation of low-temperature tar. Part II

    Energy Technology Data Exchange (ETDEWEB)

    Terres, E; Gebert, F; Huelsemann, H; Petereit, H; Toepsch, H; Ruppert, W

    1955-01-01

    Chromatographic methods and apparatus are discussed. The Folin-Denis reagent (Na tungstate molybdate in H/sub 3/PO/sub 4/) is used for developing paper chromatograms of phenol mixtures. Other reagents are given.

  3. Chromatographic determination of silicon and phosphorus as molybdic heteropoly acids with preconcentration

    International Nuclear Information System (INIS)

    Tikhomirova, T.I.; Krokhin, O.V.; Dubovik, D.B.; Ivanov, A.V.; Shpigun, O.A.

    2002-01-01

    Chromatographic behaviour of silicon and phosphorus as molybdic heteropoly acids with preconcentration as ion associations of heteropoly acid with tributylammonium bromide was studied. The technique of simultaneous analysis of silicon and phosphorus was developed. During investigation into the effect of acetonitril content in the probe on the form of chromatographic peak of molybdosilicic acid the negative influence of acetonitril on the form of peak was ascertained. This effect may be eliminated by the lowering of acetonitril content up to 50 %. It was found that under these conditions the chromatographic peak practically was absent, because of the heteropoly acid of the Mo(VI) abundance transformed in the MoO 2 2+ cation form without reaction with tributylammonium cation during concentration of heteropoly acid [ru

  4. Underway meteorological, navigational, physical and time series data collected aboard NOAA Ship Ronald H. Brown in the Bering Sea on 2015-09-04 (NCEI Accession 0137446)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NODC Accession 0137446 contains raw underway meteorological, navigational, physical and time series data logged by the Scientific Computer System (SCS) aboard NOAA...

  5. The behaviour of radionuclides in gas adsorption chromatographic processes with superimposed chemical reactions (chlorides)

    International Nuclear Information System (INIS)

    Eichler, B.

    1996-01-01

    Thermochemical relationships are derived describing the gas adsorption chromatographic transport of carrier-free radionuclides. Especially, complex adsorption processes such as dissociative, associative and substitutive adsorption are dealt with. The comparison of experimental with calculated data allows the determination of the type of adsorption reaction, which is the basis of the respective gas chromatographic process. The behaviour of carrier-free radionuclides of elements Pu, Ce, Ru, Co and Cr in thermochromatographic experiments with chlorinating carrier gases can be described as dissociative adsorption of chlorides in higher oxidation states. The gas adsorption chromatographic transport of Zr with oxygen and chlorine containing carrier gas is shown to be a substitutive adsorption process. The consequences of superimposed chemical reactions on the interpretation of results and the conception of gas adsorption chromatographic experiments with carrier-free radionuclides in isothermal columns and in temperature gradient tubes is discussed. (orig.)

  6. Chromatographic characterisation, in vitro antioxidant and free ...

    African Journals Online (AJOL)

    Chromatographic fractionation and spectroscopic analysis of the ME4 fraction revealed the presence of four compounds namely garcinia biflavonoids GB1 and GB2, garcinal and garcinoic acid. These findings show that these four compounds are partly responsible for the great antioxidant potential of G. kola seeds.

  7. Gas-chromatographic separation of hydrogen isotopic mixtures

    International Nuclear Information System (INIS)

    Preda, Anisoara; Bidica, Nicolae

    2005-01-01

    Full text: Gas chromatographic separation of hydrogen isotopes have been reported in the literature since late of 1950's. Gas chromatography is primarily an analytical method, but because of its properties it may be used in many other fields with excellent results. A simple method is proposed for the gas-chromatographic analysis of complex gas mixtures containing hydrogen isotopes; the method is based on the substantial difference in the thermal conductivity of these isotopes. One of the main disadvantages of the conventional gas chromatography is the long retention times required for the analysis of hydrogen gas mixtures while the column is operated at very low temperature. The method described in this paper was based on using a capillary molecular sieve 5A column operated for this kind of separation at 173 K. The carrier gas was Ne and the detector was TCD. In the paper chromatograms for various carrier flow rates and various hydrogen isotope mixtures are presented. (authors)

  8. [A peak recognition algorithm designed for chromatographic peaks of transformer oil].

    Science.gov (United States)

    Ou, Linjun; Cao, Jian

    2014-09-01

    In the field of the chromatographic peak identification of the transformer oil, the traditional first-order derivative requires slope threshold to achieve peak identification. In terms of its shortcomings of low automation and easy distortion, the first-order derivative method was improved by applying the moving average iterative method and the normalized analysis techniques to identify the peaks. Accurate identification of the chromatographic peaks was realized through using multiple iterations of the moving average of signal curves and square wave curves to determine the optimal value of the normalized peak identification parameters, combined with the absolute peak retention times and peak window. The experimental results show that this algorithm can accurately identify the peaks and is not sensitive to the noise, the chromatographic peak width or the peak shape changes. It has strong adaptability to meet the on-site requirements of online monitoring devices of dissolved gases in transformer oil.

  9. Validated high performance liquid chromatographic (HPLC) method ...

    African Journals Online (AJOL)

    STORAGESEVER

    2010-02-22

    Feb 22, 2010 ... specific and accurate high performance liquid chromatographic method for determination of ZER in micro-volumes ... tional medicine as a cure for swelling, sores, loss of appetite and ... Receptor Activator for Nuclear Factor κ B Ligand .... The effect of ... be suitable for preclinical pharmacokinetic studies. The.

  10. Underway meteorological, navigational, optical, physical and time series data collected aboard NOAA Ship Gordon Gunter in the Gulf of Mexico on 2016-10-01 (NCEI Accession 0164087)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NCEI Accession 0164087 contains raw underway meteorological, navigational, optical, physical and time series data logged by the Scientific Computer System (SCS)...

  11. GAS CHROMATOGRAPHIC AND SPECTROSCOPIC ANALYSIS OF ...

    African Journals Online (AJOL)

    Peroxyformic acid prepared in-situ was employed for epoxidation of canola oil in the presence of toluene. Gas chromatographic analysis of the product revealed the following species: C16:0; C18:0; C18:1; C18:2; C18:3; monoepoxy C18:0; monoepoxy C18:1; monoepoxy C18:2; diepoxy C18:0; diepoxy C18:1 and triepoxy ...

  12. Underway meteorological, navigational, physical and time series data collected aboard NOAA Ship Henry B. Bigelow in the North Atlantic Ocean on 2016-08-26 (NCEI Accession 0162238)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NCEI Accession 0162238 contains raw underway meteorological, navigational, physical and time series data logged by the Scientific Computer System (SCS) aboard NOAA...

  13. Underway meteorological, navigational, physical and time series data collected aboard NOAA Ship Oscar Elton Sette in the North Pacific Ocean on 2016-06-22 (NCEI Accession 0155170)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NCEI Accession 0155170 contains raw underway meteorological, navigational, physical and time series data logged by the Scientific Computer System (SCS) aboard NOAA...

  14. Influence of column type and chromatographic conditions on the ion-exchange chromatography of immunoglobulins.

    Science.gov (United States)

    Yang, Y B; Harrison, K

    1996-08-30

    Immunoglobulins are often purified by affinity chromatography. However, this technique is costly, can result in poor resolution for subclasses (or is only group specific), and leads to possible leaching of contaminants into the purified products. Ion-exchange chromatography has shown great potential and has found an increased usage in the purification of immunoglobulins. The aim of this study is to further understand the separation mechanism with emphasis on the influence of column type and chromatographic conditions on the peak shape, selectivity and changes in the elution patterns. Included are strong cation-exchange, strong anion-exchange and weak anion-exchange columns. Five immunoglobulin G antibodies were used as test probes. Some sera and ascites were also used in the study. Among the chromatographic conditions examined were mobile phase pH, buffer type, buffer concentration, gradient rate, and column temperature. Significant differences in the chromatographic behavior (elution pattern, peak shape and selectivity) of the test samples are discussed in regard to the column type and the chromatographic conditions.

  15. In Portugal, the energy revolution is underway

    International Nuclear Information System (INIS)

    Mary, Olivier

    2015-01-01

    As at the beginning of 2013, 70 per cent of the electricity consumed in Portugal had a renewable origin, this article outlines that this result is based on a strong-willed policy. In fact, Portugal entered the energy transition in 2001 with its '4E program' (energy efficiency and endogenous energies) which aimed at reaching 60 per cent of renewable energies in electricity consumption by 2020. This program was based on a strong development of wind and hydraulic energy. Moreover, the country developed its own capacities for the manufacturing of wind turbines. On another hand, other renewable energies (notably solar energy) seem a bit late although several projects are underway. As far as hydraulic energy, a dam project is a matter of controversy

  16. Paper chromatographic behavior of tetranitronitrosylruthenate and its decomposition products

    International Nuclear Information System (INIS)

    Akatsu, Eiko

    1981-01-01

    The paper chromatographic behavior of tetranitronitrosylruthenate was examined together with its decomposition products. First, Rf values at various eluting conditions were studied with five kinds of papers, since there was a discrepancy among the reported Rf values. Usually Rf of 0.9 was obtained by the recommended procedure of Wain, et al. Second, stability of the tetranitrosylruthenate in water was followed by paper chromatography. No change was found until 200 days passed. Third, the tetranitronitrosylruthenate was warmed in acid, and its decomposition products were studied through the paper chromatography. The paper chromatographic behavior showed that the sample kept in water more than 200 days seemed to contain a dinitro complex, and the sample warmed in acid seemed to be decomposed to a mononitro complex of further. (author)

  17. Underway meteorological, navigational, optical, physical and time series data collected aboard NOAA Ship Bell M. Shimada in the North Pacific Ocean on 2016-06-26 (NCEI Accession 0162236)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NCEI Accession 0162236 contains raw underway meteorological, navigational, optical, physical and time series data logged by the Scientific Computer System (SCS)...

  18. A low-power pressure-and temperature-programmed separation system for a micro gas chromatograph.

    Energy Technology Data Exchange (ETDEWEB)

    Sacks, Richard D. (University of Michigan, Ann Arbor, MI); Robinson, Alex Lockwood (Advanced Sensor Technologies, Albuquerque, NM); Lambertus, Gordon R. (University of Michigan, Ann Arbor, MI); Potkay, Joseph A. (University of Michigan, Ann Arbor, MI); Wise, Kensall D. (University of Michigan, Ann Arbor, MI)

    2006-10-01

    This thesis presents the theory, design, fabrication and testing of the microvalves and columns necessary in a pressure- and temperature-programmed micro gas chromatograph ({micro}GC). Two microcolumn designs are investigated: a bonded Si-glass column having a rectangular cross section and a vapor-deposited silicon oxynitride (Sion) column having a roughly circular cross section. Both microcolumns contain integrated heaters and sensors for rapid, controlled heating. The 3.2 cm x 3.2 cm, 3 m-long silicon-glass column, coated with a non-polar polydimethylsiloxane (PDMS) stationary phase, separates 30 volatile organic compounds (VOCs) in less than 6 min. This is the most efficient micromachined column reported to date, producing greater than 4000 plates/m. The 2.7 mm x 1.4 mm Sion column eliminates the glass sealing plate and silicon substrate using deposited dielectrics and is the lowest power and fastest GC column reported to date; it requires only 11 mW to raise the column temperature by 100 C and has a response time of 11s and natural temperature ramp rate of 580 C/min. A 1 m-long PDMS-coated Sion microcolumn separates 10 VOCs in 52s. A system-based design approach was used for both columns.

  19. Supercritical Fluid Chromatographic Separation of Dimethylpolysiloxane Polymer

    Energy Technology Data Exchange (ETDEWEB)

    Pyo, Dong Jin; Lim, Chang Hyun [Kangwon National University, Chuncheon (Korea, Republic of)

    2005-02-15

    Water was used as a polar modifier and a μ-porasil column as a saturator column. The μ-porasil column was inserted between the pump outlet and the injection valve. During the passage of the supercritical fluid mobile phase through the silica column, a polar modifier (water) can be dissolved in the pressurized supercritical fluid. Dimethylpolysiloxane polymer has been known as more polar polymer than polystyrene polymer. Dimethylpolysiloxane polymer has never been separated using water modified mobile phase. In this paper, using a μ-porasil column as a saturator column, excellent supercritical fluid chromatograms of dimethylpolysiloxane oligomers were obtained. The use of compressed (dense) gases and supercritical fluids as chromatographic mobile phases in conjunction with liquid chromatographic (LC)-type packed columns was first reported by Klesper et al. in 1962. During its relatively short history, supercritical fluid chromatography (SFC) has become an attractive alternative to GC and LC in certain industrially important applications. SFC gives the advantage of high efficiency and allows the analysis of nonvolatile or thermally labile mixtures.

  20. Supercritical Fluid Chromatographic Separation of Dimethylpolysiloxane Polymer

    International Nuclear Information System (INIS)

    Pyo, Dong Jin; Lim, Chang Hyun

    2005-01-01

    Water was used as a polar modifier and a μ-porasil column as a saturator column. The μ-porasil column was inserted between the pump outlet and the injection valve. During the passage of the supercritical fluid mobile phase through the silica column, a polar modifier (water) can be dissolved in the pressurized supercritical fluid. Dimethylpolysiloxane polymer has been known as more polar polymer than polystyrene polymer. Dimethylpolysiloxane polymer has never been separated using water modified mobile phase. In this paper, using a μ-porasil column as a saturator column, excellent supercritical fluid chromatograms of dimethylpolysiloxane oligomers were obtained. The use of compressed (dense) gases and supercritical fluids as chromatographic mobile phases in conjunction with liquid chromatographic (LC)-type packed columns was first reported by Klesper et al. in 1962. During its relatively short history, supercritical fluid chromatography (SFC) has become an attractive alternative to GC and LC in certain industrially important applications. SFC gives the advantage of high efficiency and allows the analysis of nonvolatile or thermally labile mixtures

  1. Chiral ionic liquids in chromatographic and electrophoretic separations.

    Science.gov (United States)

    Kapnissi-Christodoulou, Constantina P; Stavrou, Ioannis J; Mavroudi, Maria C

    2014-10-10

    This report provides an overview of the application of chiral ionic liquids (CILs) in separation technology, and particularly in capillary electrophoresis and both gas and liquid chromatography. There is a large number of CILs that have been synthesized and designed as chiral agents. However, only a few have successfully been applied in separation technology. Even though this application of CILs is still in its early stages, the scientific interest is increasing dramatically. This article is focused on the use of CILs as chiral selectors, background electrolyte additives, chiral ligands and chiral stationary phases in electrophoretic and chromatographic techniques. Different examples of CILs, which contain either a chiral cation, a chiral anion or both, are presented in this review article, and their major advantages along with their potential applications in chiral electrophoretic and chromatographic recognition are discussed. Copyright © 2014 Elsevier B.V. All rights reserved.

  2. Micro-column plasma emission liquid chromatograph. [Patent application

    Science.gov (United States)

    Gay, D.D.

    1982-08-12

    In a direct current plasma emission spectrometer for use in combination with a microcolumn liquid chromatograph, an improved plasma source unit is claimed. The plasma source unit includes a quartz capillary tube having an inlet means, outlet off gas means and a pair of spaced electrodes defining a plasma region in the tube. The inlet means is connected to and adapted to receive eluant of the liquid chromatograph along with a stream of plasma-forming gas. There is an opening through the wall of the capillary tube penetrating into the plasma region. A soft glass capillary light pipe is disposed at the opening, is connected to the spectrometer, and is adapted to transmit light passing from the plasma region to the spectrometer. There is also a source of electromotive force connected to the electrodes sufficient to initiate and sustain a plasma in the plasma region of the tube.

  3. The counterintuitive role of extra-column volume in the determination of column efficiency and scaling of chromatographic processes

    NARCIS (Netherlands)

    Schultze-Jena, A.; Boon, M.A.; Bussmann, P.J.Th.; Janssen, A.E.M.; Padt, van der A.

    2017-01-01

    In industrial liquid separation processes chromatography often has a key function in the optimization of yield and purity. For the design of an industrial system, chromatographic processes are generally simulated using mathematical models, tested and optimized at laboratory level, and then scaled

  4. The counterintuitive role of extra-column volume in the determination of column efficiency and scaling of chromatographic processes

    NARCIS (Netherlands)

    Schultze-Jena, A.; Boon, M.A.; Bussmann, P.J.T.; Janssen, A.E.M.; Padt, A. van der

    2017-01-01

    In industrial liquid separation processes chromatography often has a key function in the optimization of yield and purity. For the design of an industrial system, chromatographic processes are generally simulated using mathematical models, tested and optimized at laboratory level, and then scaled up

  5. Chromatographic methods for the simultaneous determination of binary mixture of Saxagliptin HCl and Metformin HCl

    Directory of Open Access Journals (Sweden)

    Hanan A. Merey

    2017-12-01

    Full Text Available Two chromatographic methods were suggested for the simultaneous determination of a binary mixture containing Saxagliptin HCl (SAG and Metformin HCl (MET. First method was RP-HPLC method. Chromatographic separation was done on Kinetex™ column–C18 (4.6 × 150 mm, 2.6 µm using mobile phase consisted of acetonitrile:phosphate buffer pH = 4.5 ± 0.1 adjusted with orthophosphoric acid (13:87, v/v. Isocratic elution at a flow rate 1.5 mL/min and UV detection at 220.0 nm was performed. Second method was spectro-densitometric method. Chromatographic separation was done on precoated silica gel aluminium plates 60 F254 as a stationary phase and developing system consisting of chloroform:methanol:formic acid (80:20:0.3, by volume. The density of the separated bands was measured by UV detector at 210.0 nm. The proposed methods were validated as per the ICH guidelines parameters like Linearity, precision, accuracy, selectivity, limit of detection and limit of quantitation. Statistical comparison was done between the obtained results and those obtained by the reported methods, showing no significant difference with respect to accuracy and precision. Keywords: Saxagliptin HCl, Metformin HCl, RP-HPLC, TLC

  6. Liquid chromatographic-tandem mass spectrometric assay for ...

    African Journals Online (AJOL)

    Methods: Blood and urine samples were obtained from healthy volunteers who admitted to not being on any medications. The investigated analytes were chromatographically separated on a C18 column (Luna®-PFP 100Å column, 50 mm × 2.0 mm i.d., 3.0 μm) with the aid of a mobile phase containing A; acetonitrile (ACN) ...

  7. Development, modelling, optimisation and scale-up of chromatographic purification of a therapeutic protein

    DEFF Research Database (Denmark)

    Mollerup, Jørgen; Hansen, Thomas Budde; Kidal, Steffen

    2007-01-01

    Development of a chromatographic purification step proceeds through a number of stages. High-throughput screening techniques are used to identify suitable resins. This technique is also suitable for the design of a capture step and some intermediate chromatographic steps, but development and true...... by industry. The theory of residence time based scale-up is developed and applied. (c) 2007 Elsevier B.V. All rights reserved....

  8. The development of a high performance liquid chromatograph with a sensitive on-stream radioactivity monitor for the analysis of 3H- and 14C-labelled gibberellins

    International Nuclear Information System (INIS)

    Reeve, D.R.; Yokota, T.; Nash, L.; Crozier, A.

    1976-01-01

    The development of a high performance liquid chromatograph for the separation of gibberellins is described. The system combines high efficiency, peak capacity, and sample capacity with rapid speed of analysis. In addition, the construction details of a sensitive on-stream radioactivity monitor are outlined. The overall versatility of the chromatograph has been demonstrated by the separation of a range of 3 H- and 14 C-labelled gibberellins and gibberellin precursors. The system also has considerable potential for the analysis of abscisic acid and acidic and neutral indoles. (author)

  9. Secretory immunoglobulin purification from whey by chromatographic techniques.

    Science.gov (United States)

    Matlschweiger, Alexander; Engelmaier, Hannah; Himmler, Gottfried; Hahn, Rainer

    2017-08-15

    Secretory immunoglobulins (SIg) are a major fraction of the mucosal immune system and represent potential drug candidates. So far, platform technologies for their purification do not exist. SIg from animal whey was used as a model to develop a simple, efficient and potentially generic chromatographic purification process. Several chromatographic stationary phases were tested. A combination of two anion-exchange steps resulted in the highest purity. The key step was the use of a small-porous anion exchanger operated in flow-through mode. Diffusion of SIg into the resin particles was significantly hindered, while the main impurities, IgG and serum albumin, were bound. In this step, initial purity was increased from 66% to 89% with a step yield of 88%. In a second anion-exchange step using giga-porous material, SIg was captured and purified by step or linear gradient elution to obtain fractions with purities >95%. For the step gradient elution step yield of highly pure SIg was 54%. Elution of SIgA and SIgM with a linear gradient resulted in a step yield of 56% and 35%, respectively. Overall yields for both anion exchange steps were 43% for the combination of flow-through and step elution mode. Combination of flow-through and linear gradient elution mode resulted in a yield of 44% for SIgA and 39% for SIgM. The proposed process allows the purification of biologically active SIg from animal whey in preparative scale. For future applications, the process can easily be adopted for purification of recombinant secretory immunoglobulin species. Copyright © 2017 Elsevier B.V. All rights reserved.

  10. Optimization of the gas chromatographic separations; Optimacion de las separaciones cromatograficas en fase gaseosa

    Energy Technology Data Exchange (ETDEWEB)

    Gasco Sanchez, L

    1973-07-01

    A review and a critical study on the optimization of the gas chromatographic separations are made. After dealing with the fundamental gas chromatographic equations, some methods of expressing column performances are discussed: performance indices, performance parameters, resolution and effective plate number per unit time. This is completed with a comparative study on performances of various types of columns. Moreover, optimization methods for operating chromatographic conditions are extensively dealt with: as resolution optimization, separation time, and normalization techniques for the time of analysis in order to achieve the maximum resolution at constant time. Finally, some others non operating parameters such as: selectivity of stationary phases, column preparation and optimization methods by means of computers are studied. (Author) 68 refs.

  11. Development and Validation of a Liquid Chromatographic Method ...

    African Journals Online (AJOL)

    A liquid chromatographic method for the simultaneous determination of six human immunodeficiency virus (HIV) protease inhibitors, indinavir, saquinavir, ritonavir, amprenavir, nelfinavir and lopinavir, was developed and validated. Optimal separation was achieved on a PLRP-S 100 Å, 250 x 4.6 mm I.D. column maintained ...

  12. Sensitive high performance liquid chromatographic method for the ...

    African Journals Online (AJOL)

    A new simple, sensitive, cost-effective and reproducible high performance liquid chromatographic (HPLC) method for the determination of proguanil (PG) and its metabolites, cycloguanil (CG) and 4-chlorophenylbiguanide (4-CPB) in urine and plasma is described. The extraction procedure is a simple three-step process ...

  13. Studies on Brucella interferon: Chromatographic behaviour and purification

    International Nuclear Information System (INIS)

    Bousquet-Ucla, C.; Wietzerbin, J.; Falcoff, E.

    1980-01-01

    Interferon was induced by infecting mice with Brucella suis. Serum containing interferon activity was analyzed by chromatography on Concanavalin A-Sepharose and Phenyl-Sepharose CL-4B columns. Antiviral activity was completely retained by the lectin column indicating that all the interferon molecules are glycosylated. The chromatographic behaviour of Brucella interferon on Phenyl-Sepharose CL-4B show that, like other interferons, Brucella interferon displays hydrophobic properties. However, the hydrophobicity of the interferon molecule was masked in the crude preparation and was only detectable when purified Brucella interferon was used for chromatography. The antigenic properties of Brucella interferon provided the means for developing an affinity chromatographic method resulting in about 60.000 fold purification. As in the case of viral interferon, treatment of L cells with Brucella interferon induced specific enhanced in vitro phosphorylation of a 67.000 molecular weight protein after incubation of cell extracts with doublestranded RNA and [γ- 32 p]ATP. (auth.)

  14. Chromatographic determination of Terbinafine in presence of its Photodegradation products

    International Nuclear Information System (INIS)

    Abdel-Moety, E.M.; Kelani, K.O.; Abou Al-Alamein, A.M.

    2003-01-01

    Two different chromatographic techniques have been developed for the determination of terbinafine hydrochloride in presence of its photodegradation products. The first method depends on coupling the TLC- fractionation, on silicia gel 60F254 utilizing chloroform+methanol+25% aq. ammonia ( 12: 0.1:0.1,by volumes), with the direct scanning at 284nm. The second method describes a liquid chromatographic separation of terbinafine and its photolytic degradates on a reversed-phase column[u-Bondapak-TMC 18 (10um,25cmx4.6mm,i.d.)] using a mobile phase containing methanol+water= 80:20 (v/v) with UV-detection at 284 nm. The proposed methods showed significant stability-indication with good linearity, precision and reproducibility. (author)

  15. Underway meteorological, navigational, physical and time series data collected aboard NOAA Ship Rainier in the Gulf of Alaska from 2014-05-19 to 2014-09-04 (NODC Accession 0123694)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NCEI Accession 0123694 contains raw underway meteorological, navigational, physical and time series data logged by the Scientific Computer System (SCS) aboard NOAA...

  16. Underway meteorological, navigational, physical and time series data collected aboard NOAA Ship Fairweather in the Gulf of Alaska from 2014-04-28 to 2014-07-28 (NODC Accession 0126498)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NODC Accession 0126498 contains raw underway meteorological, navigational, physical and time series data logged by the Scientific Computer System (SCS) aboard NOAA...

  17. Underway meteorological, navigational, physical and time series data collected aboard NOAA Ship Rainier in the Gulf of Alaska from 2015-09-16 to 2015-09-25 (NCEI Accession 0138191)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NODC Accession 0138191 contains raw underway meteorological, navigational, physical and time series data logged by the Scientific Computer System (SCS) aboard NOAA...

  18. Underway meteorological, navigational, physical and time series data collected aboard NOAA Ship Rainier in the Gulf of Alaska from 2014-06-04 to 2014-06-20 (NCEI Accession 0141106)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NODC Accession 0141106 contains raw underway meteorological, navigational, physical and time series data logged by the Scientific Computer System (SCS) aboard NOAA...

  19. Chromatographic, Spectroscopic and Mass Spectrometric Approaches for Exploring the Habitability of Mars in 2012 and Beyond with the Curiosity Rover

    Science.gov (United States)

    Mahaffy, Paul

    2012-01-01

    The Sample Analysis at Mars (SAM) suite of instruments on the Curiosity Rover of Mars Science Laboratory Mission is designed to provide chemical and isotopic analysis of organic and inorganic volatiles for both atmospheric and solid samples. The goals of the science investigation enabled by the gas chromatograph mass spectrometer and tunable laser spectrometer instruments of SAM are to work together with the other MSL investigations is to quantitatively assess habitability through a series of chemical and geological measurements. We describe the multi-column gas chromatograph system employed on SAM and the approach to extraction and analysis of organic compounds that might be preserved in ancient martian rocks.

  20. An integrated methodological approach to the computer-assisted gas chromatographic screening of basic drugs in biological fluids using nitrogen selective detection.

    Science.gov (United States)

    Dugal, R; Massé, R; Sanchez, G; Bertrand, M J

    1980-01-01

    This paper presents the methodological aspects of a computerized system for the gas-chromatographic screening and primary identification of central nervous system stimulants and narcotic analgesics (including some of their respective metabolites) extracted from urine. The operating conditions of a selective nitrogen detector for optimized analytical functions are discussed, particularly the effect of carrier and fuel gas on the detector's sensitivity to nitrogen-containing molecules and discriminating performance toward biological matrix interferences. Application of simple extraction techniques, combined with rapid derivatization procedures, computer data acquisition, and reduction of chromatographic data are presented. Results show that this system approach allows for the screening of several drugs and their metabolites in a short amount of time. The reliability and stability of the system have been tested by analyzing several thousand samples for doping control at major international sporting events and for monitoring drug intake in addicts participating in a rehabilitation program. Results indicate that these techniques can be used and adapted to many different analytical toxicology situations.

  1. [Sample preparation methods for chromatographic analysis of organic components in atmospheric particulate matter].

    Science.gov (United States)

    Hao, Liang; Wu, Dapeng; Guan, Yafeng

    2014-09-01

    The determination of organic composition in atmospheric particulate matter (PM) is of great importance in understanding how PM affects human health, environment, climate, and ecosystem. Organic components are also the scientific basis for emission source tracking, PM regulation and risk management. Therefore, the molecular characterization of the organic fraction of PM has become one of the priority research issues in the field of environmental analysis. Due to the extreme complexity of PM samples, chromatographic methods have been the chief selection. The common procedure for the analysis of organic components in PM includes several steps: sample collection on the fiber filters, sample preparation (transform the sample into a form suitable for chromatographic analysis), analysis by chromatographic methods. Among these steps, the sample preparation methods will largely determine the throughput and the data quality. Solvent extraction methods followed by sample pretreatment (e. g. pre-separation, derivatization, pre-concentration) have long been used for PM sample analysis, and thermal desorption methods have also mainly focused on the non-polar organic component analysis in PM. In this paper, the sample preparation methods prior to chromatographic analysis of organic components in PM are reviewed comprehensively, and the corresponding merits and limitations of each method are also briefly discussed.

  2. Multidimensional High-Resolution Gas Chromatographic Investigations of Hydrocarbon Fuels and Various Turbine Engine Fuel Precursors.

    Science.gov (United States)

    1985-08-01

    time were spurious transits observed during the recording of the chromatographic output data. *Packaged gas purification filters supplied by Alltech ... Alltech ) that were needed for these unusual installations. When the column diameters were small and of comparable size, the assembly attach- ments at...into an MDGC system has definite advantages as separations can be made faster and with greater detectability. However, specific precautions must be

  3. Underway navigational, physical and time series data collected aboard NOAA Ship Thomas Jefferson in the North Atlantic Ocean from 2013-06-17 to 2013-10-02 (NODC Accession 0123055)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NODC Accession 0123055 contains raw underway navigational, physical and time series data logged by the Scientific Computer System (SCS) aboard NOAA Ship Thomas...

  4. OpenChrom: a cross-platform open source software for the mass spectrometric analysis of chromatographic data.

    Science.gov (United States)

    Wenig, Philip; Odermatt, Juergen

    2010-07-30

    Today, data evaluation has become a bottleneck in chromatographic science. Analytical instruments equipped with automated samplers yield large amounts of measurement data, which needs to be verified and analyzed. Since nearly every GC/MS instrument vendor offers its own data format and software tools, the consequences are problems with data exchange and a lack of comparability between the analytical results. To challenge this situation a number of either commercial or non-profit software applications have been developed. These applications provide functionalities to import and analyze several data formats but have shortcomings in terms of the transparency of the implemented analytical algorithms and/or are restricted to a specific computer platform. This work describes a native approach to handle chromatographic data files. The approach can be extended in its functionality such as facilities to detect baselines, to detect, integrate and identify peaks and to compare mass spectra, as well as the ability to internationalize the application. Additionally, filters can be applied on the chromatographic data to enhance its quality, for example to remove background and noise. Extended operations like do, undo and redo are supported. OpenChrom is a software application to edit and analyze mass spectrometric chromatographic data. It is extensible in many different ways, depending on the demands of the users or the analytical procedures and algorithms. It offers a customizable graphical user interface. The software is independent of the operating system, due to the fact that the Rich Client Platform is written in Java. OpenChrom is released under the Eclipse Public License 1.0 (EPL). There are no license constraints regarding extensions. They can be published using open source as well as proprietary licenses. OpenChrom is available free of charge at http://www.openchrom.net.

  5. Separation and determination of high-carbon alcohols using method of column chromatographic and gas-chromatographic analysis

    International Nuclear Information System (INIS)

    Kang Zhongrong; Li Biping; Zeng Yongchang

    1988-01-01

    This paper describes the separation and determination of high-carbon alcohols from amine extractant by using the method of column chromatography of aluminium oxide and gas-chromatographic analysis. The total conent of high-carbon alcohols is determined by the method of column chromatography, while the components of the high-carbon alcohols and their relative contents are determined by the method of gas-chromatography. A simple reliable and practical method is provided for the analysis of high-carbon alcohol from the amine extractant in this paper

  6. Recent Advances in Water Analysis with Gas Chromatograph Mass Spectrometers

    Science.gov (United States)

    MacAskill, John A.; Tsikata, Edem

    2014-01-01

    We report on progress made in developing a water sampling system for detection and analysis of volatile organic compounds in water with a gas chromatograph mass spectrometer (GCMS). Two approaches are described herein. The first approach uses a custom water pre-concentrator for performing trap and purge of VOCs from water. The second approach uses a custom micro-volume, split-splitless injector that is compatible with air and water. These water sampling systems will enable a single GC-based instrument to analyze air and water samples for VOC content. As reduced mass, volume, and power is crucial for long-duration, manned space-exploration, these water sampling systems will demonstrate the ability of a GCMS to monitor both air and water quality of the astronaut environment, thereby reducing the amount of required instrumentation for long duration habitation. Laboratory prototypes of these water sampling systems have been constructed and tested with a quadrupole ion trap mass spectrometer as well as a thermal conductivity detector. Presented herein are details of these water sampling system with preliminary test results.

  7. Underway meteorological, navigational, optical, physical and time series data collected aboard NOAA Ship Oscar Dyson in the Bering Sea from 2014-06-12 to 2014-08-14 (NODC Accession 0124303)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NODC Accession 0124303 contains raw underway meteorological, navigational, optical, physical and time series data logged by the Scientific Computer System (SCS)...

  8. Underway meteorological, navigational, optical, physical and time series data collected aboard NOAA Ship Pisces in the North Atlantic Ocean from 2013-07-01 to 2013-07-12 (NODC Accession 0117838)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NODC Accession 0117838 contains raw underway meteorological, navigational, optical, physical and time series data logged by the Scientific Computer System (SCS)...

  9. Underway meteorological, navigational, optical, physical and time series data collected aboard NOAA Ship Oscar Dyson in the Bering Sea from 2016-05-03 to 2016-05-04 (NCEI Accession 0165030)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NCEI Accession 0165030 contains raw underway meteorological, navigational, optical, physical and time series data logged by the Scientific Computer System (SCS)...

  10. Underway meteorological, navigational, optical, physical and time series data collected aboard NOAA Ship Pisces in the North Atlantic Ocean from 2016-10-18 to 2016-10-20 (NCEI Accession 0164092)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NCEI Accession 0164092 contains raw underway meteorological, navigational, optical, physical and time series data logged by the Scientific Computer System (SCS)...

  11. Underway meteorological, navigational, optical, physical and time series data collected aboard NOAA Ship Pisces in the North Atlantic Ocean from 2016-11-12 to 2016-11-18 (NCEI Accession 0164093)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NCEI Accession 0164093 contains raw underway meteorological, navigational, optical, physical and time series data logged by the Scientific Computer System (SCS)...

  12. Underway meteorological, navigational, optical, physical and time series data collected aboard NOAA Ship Oscar Dyson in the Bering Sea from 2016-08-22 to 2016-09-20 (NCEI Accession 0165088)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NCEI Accession 0165088 contains raw underway meteorological, navigational, optical, physical and time series data logged by the Scientific Computer System (SCS)...

  13. Underway meteorological, navigational, optical, physical and time series data collected aboard NOAA Ship Oscar Dyson in the Bering Sea from 2014-05-06 to 2014-05-17 (NODC Accession 0125087)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NODC Accession 0125087 contains raw underway meteorological, navigational, optical, physical and time series data logged by the Scientific Computer System (SCS)...

  14. Underway meteorological, navigational, optical, physical and time series data collected aboard NOAA Ship Oscar Dyson in the Bering Sea from 2016-09-24 to 2016-10-01 (NCEI Accession 0165089)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NCEI Accession 0165089 contains raw underway meteorological, navigational, optical, physical and time series data logged by the Scientific Computer System (SCS)...

  15. Underway meteorological, navigational, optical, physical and time series data collected aboard NOAA Ship Oscar Dyson in the Bering Sea from 2016-06-12 to 2016-08-17 (NCEI Accession 0165031)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NCEI Accession 0165031 contains raw underway meteorological, navigational, optical, physical and time series data logged by the Scientific Computer System (SCS)...

  16. Underway meteorological, navigational, optical, physical and time series data collected aboard NOAA Ship Oscar Dyson in the Bering Sea from 2016-05-18 to 2016-06-08 (NCEI Accession 0165363)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NCEI Accession 0165363 contains raw underway meteorological, navigational, optical, physical and time series data logged by the Scientific Computer System (SCS)...

  17. Underway meteorological, navigational, optical, physical and time series data collected aboard NOAA Ship Oscar Dyson in the Bering Sea from 2015-09-06 to 2015-09-18 (NCEI Accession 0137412)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NODC Accession 0137412 contains raw underway meteorological, navigational, optical, physical and time series data logged by the Scientific Computer System (SCS)...

  18. Underway meteorological, navigational, optical, physical and time series data collected aboard NOAA Ship Oscar Dyson in the Bering Sea from 2014-05-20 to 2014-06-08 (NODC Accession 0125267)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NODC Accession 0125267 contains raw underway meteorological, navigational, optical, physical and time series data logged by the Scientific Computer System (SCS)...

  19. Partial pressure (or fugacity) of carbon dioxide, salinity and other variables collected from underway - surface observations using gas chromatograph and other instruments from the LILLOOET in the Coastal Waters of SE Alaska, Coral Sea and others from 1988-02-04 to 1988-02-20 (NODC Accession 0000439)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NODC Accession 0000439 includes chemical, meteorological, physical and underway - surface data collected from LILLOOET in the Coastal Waters of SE Alaska, Coral Sea,...

  20. High Performance Liquid Chromatographic Method for Determination of Dipyridamole in Human Plasma

    Directory of Open Access Journals (Sweden)

    DAVOOD BEIGI BAND ARAB ADI

    1999-08-01

    Full Text Available A simple, rapid and specific high-performance liquid chromatographic procedure is reported for"nquantitative determination of dipyridamole in human -plasma. The assay uses a reversed-phase"nhigh-performance liquid chromatographic (HPLC and UV detection at 280nm and has a limit"nof detection of approximately 5ng/mL. The mobile phase consists of MeOH-H20 (60:40"nadjusted to pH 3.3. Dipyridamole was extracted from plasma by back-extraction procedure, with"npropranolol as the internal standard. The reproducibility of the method is satisfactory

  1. Gas chromatographic/mass spectrometric determination of carbon isotope composition in unpurified samples: methamphetamine example.

    Science.gov (United States)

    Low, I A; Liu, R H; Legendre, M G; Piotrowski, E G; Furner, R L

    1986-10-01

    A gas chromatograph/quadrupole mass spectrometer system, operated in electron impact/selected ion monitoring mode, is used to determine the intensity ratio of the m/z 59 and the m/z 58 ions of the [C3H8N]+ fragment derived from methamphetamine samples synthesized with varying amounts of 13C-labeled methylamine. Crude products are introduced into the gas chromatograph without prior cleanup. The ratios measured were in excellent agreement with those calculated. A change in 0.25% use of 13C-methylamine is sufficient for product differentiation. The feasibility of using isotope labeling and subsequent mass spectrometric isotope ratio measurement as the basis of a compound tracing mechanism is discussed. Specifically, if methamphetamine samples manufactured from legal sources are asked to incorporate distinct 13C compositions, their sources can be traced when samples are diverted into illegal channels. Samples derived from illicit preparations can also be traced if the manufacturers of a precursor (methylamine in this case) incorporate distinct 13C compositions in their products.

  2. Underway meteorological, navigational, physical and time series data collected aboard NOAA Ship Okeanos Explorer in the North Pacific Ocean from 2015-07-10 to 2015-09-03 (NCEI Accession 0141435)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NODC Accession 0141435 contains raw underway meteorological, navigational, physical and time series data logged by the Scientific Computer System (SCS) aboard NOAA...

  3. Underway meteorological, navigational, physical and time series data collected aboard NOAA Ship Hi'ialakai in the North Pacific Ocean from 2015-07-09 to 2015-07-16 (NCEI Accession 0129903)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NODC Accession 0129903 contains raw underway meteorological, navigational, physical and time series data logged by the Scientific Computer System (SCS) aboard NOAA...

  4. Underway meteorological, navigational, physical and time series data collected aboard NOAA Ship Thomas Jefferson in the North Atlantic Ocean from 2013-09-24 to 2013-11-04 (NODC Accession 0123614)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NODC Accession 0123614 contains raw underway meteorological, navigational, physical and time series data logged by the Scientific Computer System (SCS) aboard NOAA...

  5. Underway meteorological, navigational, physical and time series data collected aboard NOAA Ship Okeanos Explorer in the North Pacific Ocean from 2015-10-07 to 2015-10-16 (NCEI Accession 0150689)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NCEI Accession 0150689 contains raw underway meteorological, navigational, physical and time series data logged by the Scientific Computer System (SCS) aboard NOAA...

  6. Underway meteorological, navigational, physical and time series data collected aboard NOAA Ship Okeanos Explorer in the North Atlantic Ocean from 2014-08-09 to 2014-10-07 (NODC Accession 0125346)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NODC Accession 0125346 contains raw underway meteorological, navigational, physical and time series data logged by the Scientific Computer System (SCS) aboard NOAA...

  7. Underway meteorological, navigational, physical and time series data collected aboard NOAA Ship Hi'ialakai in the North Pacific Ocean from 2013-07-09 to 2013-07-16 (NODC Accession 0113243)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NODC Accession 0113243 contains raw underway meteorological, navigational, physical and time series data logged by the Scientific Computer System (SCS) aboard NOAA...

  8. Underway meteorological, navigational, physical and time series data collected aboard NOAA Ship Nancy Foster in the North Atlantic Ocean from 2014-05-19 to 2014-05-20 (NODC Accession 0118685)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NODC Accession 0118685 contains raw underway meteorological, navigational, physical and time series data logged by the Scientific Computer System (SCS) aboard NOAA...

  9. Underway meteorological, navigational, physical and time series data collected aboard NOAA Ship Hi'ialakai in the North Pacific Ocean from 2013-06-26 to 2013-07-03 (NODC Accession 0099244)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NODC Accession 0099244 contains raw underway meteorological, navigational, physical and time series data logged by the Scientific Computer System (SCS) aboard NOAA...

  10. Underway meteorological, navigational, physical and time series data collected aboard NOAA Ship Hi'ialakai in the North Pacific Ocean from 2015-07-27 to 2015-08-27 (NCEI Accession 0133933)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NCEI Accession 0133933 contains raw underway meteorological, navigational, physical and time series data logged by the Scientific Computer System (SCS) aboard NOAA...

  11. Underway meteorological, navigational, physical and time series data collected aboard NOAA Ship Thomas Jefferson in the North Atlantic Ocean from 2014-04-04 to 2014-11-18 (NODC Accession 0122407)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NCEI Accession 0122407 contains raw underway meteorological, navigational, physical and time series data logged by the Scientific Computer System (SCS) aboard NOAA...

  12. Underway meteorological, navigational, physical and time series data collected aboard NOAA Ship Okeanos Explorer in the North Atlantic Ocean from 2015-02-09 to 2015-02-13 (NODC Accession 0125757)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NODC Accession 0125757 contains raw underway meteorological, navigational, physical and time series data logged by the Scientific Computer System (SCS) aboard NOAA...

  13. Underway meteorological, navigational, physical and time series data collected aboard NOAA Ship Okeanos Explorer in the North Pacific Ocean from 2015-09-12 to 2015-09-30 (NCEI Accession 0142173)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NODC Accession 0142173 contains raw underway meteorological, navigational, physical and time series data logged by the Scientific Computer System (SCS) aboard NOAA...

  14. Underway meteorological, navigational, physical and time series data collected aboard NOAA Ship Thomas Jefferson in the North Atlantic Ocean from 2017-07-11 to 2017-07-22 (NCEI Accession 0164798)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NCEI Accession 0164798 contains raw underway meteorological, navigational, physical and time series data logged by the Scientific Computer System (SCS) aboard NOAA...

  15. Underway meteorological, navigational, physical and time series data collected aboard NOAA Ship Thomas Jefferson in the North Atlantic Ocean from 2017-07-22 to 2017-07-26 (NCEI Accession 0164960)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NCEI Accession 0164960 contains raw underway meteorological, navigational, physical and time series data logged by the Scientific Computer System (SCS) aboard NOAA...

  16. Underway meteorological, navigational, optical and physical data collected aboard NOAA Ship Oscar Elton Sette in the North Pacific Ocean from 2013-09-11 to 2013-09-30 (NODC Accession 0117012)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NODC Accession 0117012 contains raw underway meteorological, navigational, optical and physical data logged by the Scientific Computer System (SCS) aboard NOAA Ship...

  17. Underway meteorological, navigational, physical and time series data collected aboard NOAA Ship Nancy Foster in the North Atlantic Ocean from 2014-04-20 to 2014-04-30 (NODC Accession 0118187)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NODC Accession 0118187 contains raw underway meteorological, navigational, physical and time series data logged by the Scientific Computer System (SCS) aboard NOAA...

  18. Underway meteorological, navigational, physical and time series data collected aboard NOAA Ship Hi'ialakai in the North Pacific Ocean from 2014-09-06 to 2014-09-30 (NODC Accession 0122499)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NODC Accession 0122499 contains raw underway meteorological, navigational, physical and time series data logged by the Scientific Computer System (SCS) aboard NOAA...

  19. Underway meteorological, navigational, physical and time series data collected aboard NOAA Ship Thomas Jefferson in the North Atlantic Ocean from 2013-03-11 to 2013-03-13 (NODC Accession 0123054)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NODC Accession 0123054 contains raw underway meteorological, navigational, physical and time series data logged by the Scientific Computer System (SCS) aboard NOAA...

  20. Underway meteorological, navigational, physical and time series data collected aboard NOAA Ship Thomas Jefferson in the North Atlantic Ocean from 2015-06-24 to 2015-07-03 (NCEI Accession 0142627)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NODC Accession 0142627 contains raw underway meteorological, navigational, physical and time series data logged by the Scientific Computer System (SCS) aboard NOAA...

  1. Underway meteorological, navigational, physical and time series data collected aboard NOAA Ship Nancy Foster in the North Atlantic Ocean from 2014-11-12 to 2014-11-21 (NODC Accession 0125582)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NODC Accession 0125582 contains raw underway meteorological, navigational, physical and time series data logged by the Scientific Computer System (SCS) aboard NOAA...

  2. Chromatographic air analyser microsystem for the selective and sensitive detection of atmospheric pollutants

    International Nuclear Information System (INIS)

    Sanchez, Jean-Baptiste; Lahlou, Houda; Mohsen, Yehya; Berger, Franck; Vilanova, Xavier; Correig, Xavier

    2011-01-01

    The development of industry and automotive trafic produces Volatile Organic Compounds (VOCs) whose toxicity can affect seriously human health and environment. The level of those contaminants in air must be as low as possible. In this context, there is a need for in situ systems that could monitor selectively the concentration of these compounds. The aim of this study is to demonstrate the efficiency of a system build with a pre-concentrator, a chromatographic micro-column and a tin oxide-based gas sensor for the selective and sensitive detection of atmospheric pollutants. In particular, this study is focused on the selective detection of benzene and 1,3 butadiene.

  3. Headspace gas chromatographic method for the measurement of difluoroethane in blood.

    Science.gov (United States)

    Broussard, L A; Broussard, A; Pittman, T; Lafferty, D; Presley, L

    2001-01-01

    To develop a gas chromatographic assay for the analysis of difluoroethane, a volatile substance, in blood and to determine assay characteristics including linearity, limit of quantitation, precision, and specificity. Referral toxicology laboratory Difluoroethane, a colorless, odorless, highly flammable gas used as a refrigerant blend component and aerosol propellant, may be abused via inhalation. A headspace gas chromatographic procedure for the identification and quantitation of difluoroethane in blood is presented. A methanolic stock standard prepared from pure gaseous difluoroethane was used to prepare whole blood calibrators. Quantitation of difluoroethane was performed using a six-point calibration curve and an internal standard of 1-propanol. The assay is linear from 0 to 115 mg/L including a low calibrator at 4 mg/L, the limit of quantitation. Within-run coefficients of variation at mean concentrations of 13.8 mg/L and 38.5 mg/L were 5.8% and 6.8% respectively. Between-run coefficients of variation at mean concentrations of 15.9 mg/L and 45.7 mg/L were 13.4% and 9.8% respectively. Several volatile substances were tested as potential interfering compounds with propane having a retention time identical to that of difluoroethane. This method requires minimal sample preparation, is rapid and reproducible, can be modified for the quantitation of other volatiles, and could be automated using an automatic sampler/injector system.

  4. Similarity analyses of chromatographic herbal fingerprints: a review.

    Science.gov (United States)

    Goodarzi, Mohammad; Russell, Paul J; Vander Heyden, Yvan

    2013-12-04

    Herbal medicines are becoming again more popular in the developed countries because being "natural" and people thus often assume that they are inherently safe. Herbs have also been used worldwide for many centuries in the traditional medicines. The concern of their safety and efficacy has grown since increasing western interest. Herbal materials and their extracts are very complex, often including hundreds of compounds. A thorough understanding of their chemical composition is essential for conducting a safety risk assessment. However, herbal material can show considerable variability. The chemical constituents and their amounts in a herb can be different, due to growing conditions, such as climate and soil, the drying process, the harvest season, etc. Among the analytical methods, chromatographic fingerprinting has been recommended as a potential and reliable methodology for the identification and quality control of herbal medicines. Identification is needed to avoid fraud and adulteration. Currently, analyzing chromatographic herbal fingerprint data sets has become one of the most applied tools in quality assessment of herbal materials. Mostly, the entire chromatographic profiles are used to identify or to evaluate the quality of the herbs investigated. Occasionally only a limited number of compounds are considered. One approach to the safety risk assessment is to determine whether the herbal material is substantially equivalent to that which is either readily consumed in the diet, has a history of application or has earlier been commercialized i.e. to what is considered as reference material. In order to help determining substantial equivalence using fingerprint approaches, a quantitative measurement of similarity is required. In this paper, different (dis)similarity approaches, such as (dis)similarity metrics or exploratory analysis approaches applied on herbal medicinal fingerprints, are discussed and illustrated with several case studies. Copyright © 2013

  5. Chromatographic fingerprint similarity analysis for pollutant source identification

    International Nuclear Information System (INIS)

    Xie, Juan-Ping; Ni, Hong-Gang

    2015-01-01

    In the present study, a similarity analysis method was proposed to evaluate the source-sink relationships among environmental media for polybrominated diphenyl ethers (PBDEs), which were taken as the representative contaminants. Chromatographic fingerprint analysis has been widely used in the fields of natural products chemistry and forensic chemistry, but its application to environmental science has been limited. We established a library of various sources of media containing contaminants (e.g., plastics), recognizing that the establishment of a more comprehensive library allows for a better understanding of the sources of contamination. We then compared an environmental complex mixture (e.g., sediment, soil) with the profiles in the library. These comparisons could be used as the first step in source tracking. The cosine similarities between plastic and soil or sediment ranged from 0.53 to 0.68, suggesting that plastic in electronic waste is an important source of PBDEs in the environment, but it is not the only source. A similarity analysis between soil and sediment indicated that they have a source-sink relationship. Generally, the similarity analysis method can encompass more relevant information of complex mixtures in the environment than a profile-based approach that only focuses on target pollutants. There is an inherent advantage to creating a data matrix containing all peaks and their relative levels after matching the peaks based on retention times and peak areas. This data matrix can be used for source identification via a similarity analysis without quantitative or qualitative analysis of all chemicals in a sample. - Highlights: • Chromatographic fingerprint analysis can be used as the first step in source tracking. • Similarity analysis method can encompass more relevant information of pollution. • The fingerprints strongly depend on the chromatographic conditions. • A more effective and robust method for identifying similarities is required

  6. Underway meteorological, navigational, optical, physical and time series data collected aboard NOAA Ship Gordon Gunter in the North Atlantic Ocean from 2014-05-05 to 2014-05-09 (NCEI Accession 0149716)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NCEI Accession 0149716 contains raw underway meteorological, navigational, optical, physical and time series data logged by the Scientific Computer System (SCS)...

  7. Underway meteorological, navigational, optical, physical, profile and time series data collected aboard NOAA Ship Pisces in the Gulf of Mexico from 2013-10-22 to 2013-12-07 (NCEI Accession 0142630)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NCEI Accession 0142630 contains raw underway meteorological, navigational, optical, physical, profile and time series data logged by the Scientific Computer System...

  8. Underway meteorological, navigational, optical, physical, profile and time series data collected aboard NOAA Ship Pisces in the Gulf of Mexico from 2014-05-27 to 2014-09-30 (NODC Accession 0119414)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NODC Accession 0119414 contains raw underway meteorological, navigational, optical, physical, profile and time series data logged by the Scientific Computer System...

  9. Underway meteorological, navigational, optical, physical and time series data collected aboard NOAA Ship Reuben Lasker in the North Pacific Ocean from 2016-03-22 to 2016-04-23 (NCEI Accession 0150873)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NCEI Accession 0150873 contains raw underway meteorological, navigational, optical, physical and time series data logged by the Scientific Computer System (SCS)...

  10. Underway meteorological, navigational, optical, physical and time series data collected aboard NOAA Ship Reuben Lasker in the North Pacific Ocean from 2016-04-26 to 2016-05-19 (NCEI Accession 0153493)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NCEI Accession 0153493 contains raw underway meteorological, navigational, optical, physical and time series data logged by the Scientific Computer System (SCS)...

  11. Underway meteorological, navigational, optical, physical and time series data collected aboard NOAA Ship Okeanos Explorer in the North Atlantic Ocean from 2014-02-08 to 2014-02-10 (NODC Accession 0123613)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NODC Accession 0123613 contains raw underway meteorological, navigational, optical, physical and time series data logged by the Scientific Computer System (SCS)...

  12. Underway meteorological, navigational, optical, physical and time series data collected aboard NOAA Ship Reuben Lasker in the North Pacific Ocean from 2016-10-06 to 2016-10-13 (NCEI Accession 0164089)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NCEI Accession 0164089 contains raw underway meteorological, navigational, optical, physical and time series data logged by the Scientific Computer System (SCS)...

  13. Underway meteorological, navigational, optical, physical, profile and time series data collected aboard NOAA Ship Pisces in the Gulf of Mexico from 2015-08-24 to 2015-09-10 (NCEI Accession 0132045)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NODC Accession 0132045 contains raw underway meteorological, navigational, optical, physical, profile and time series data logged by the Scientific Computer System...

  14. Underway meteorological, navigational, optical, physical and time series data collected aboard NOAA Ship Nancy Foster in the North Atlantic Ocean from 2013-07-12 to 2013-07-21 (NODC Accession 0113448)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NODC Accession 0113448 contains raw underway meteorological, navigational, optical, physical and time series data logged by the Scientific Computer System (SCS)...

  15. Underway meteorological, navigational, optical, physical and time series data collected aboard NOAA Ship Reuben Lasker in the North Pacific Ocean from 2017-03-21 to 2017-04-22 (NCEI Accession 0164340)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NCEI Accession 0164340 contains raw underway meteorological, navigational, optical, physical and time series data logged by the Scientific Computer System (SCS)...

  16. Underway meteorological, navigational, optical, physical and time series data collected aboard NOAA Ship Reuben Lasker in the North Pacific Ocean from 2016-01-06 to 2016-01-30 (NCEI Accession 0150692)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NCEI Accession 0150692 contains raw underway meteorological, navigational, optical, physical and time series data logged by the Scientific Computer System (SCS)...

  17. Underway meteorological, navigational, optical, physical, profile and time series data collected aboard NOAA Ship Pisces in the North Atlantic Ocean from 2015-06-18 to 2015-07-01 (NCEI Accession 0129541)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NODC Accession 0129541 contains raw underway meteorological, navigational, optical, physical, profile and time series data logged by the Scientific Computer System...

  18. Underway meteorological, navigational, optical, physical, profile and time series data collected aboard NOAA Ship Pisces in the North Atlantic Ocean from 2016-09-21 to 2016-09-29 (NCEI Accession 0164083)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NCEI Accession 0164083 contains raw underway meteorological, navigational, optical, physical, profile and time series data logged by the Scientific Computer System...

  19. Underway meteorological, navigational, optical, physical, profile and time series data collected aboard NOAA Ship Pisces in the North Atlantic Ocean from 2016-07-03 to 2016-08-03 (NCEI Accession 0155990)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NCEI Accession 0155990 contains raw underway meteorological, navigational, optical, physical, profile and time series data logged by the Scientific Computer System...

  20. Underway meteorological, navigational, optical, physical, profile and time series data collected aboard NOAA Ship Pisces in the North Atlantic Ocean from 2016-10-04 to 2016-10-13 (NCEI Accession 0164086)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NCEI Accession 0164086 contains raw underway meteorological, navigational, optical, physical, profile and time series data logged by the Scientific Computer System...

  1. Underway meteorological, navigational, optical, physical, profile and time series data collected aboard NOAA Ship Pisces in the North Atlantic Ocean from 2017-06-20 to 2017-07-06 (NCEI Accession 0165349)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NCEI Accession 0165349 contains raw underway meteorological, navigational, optical, physical, profile and time series data logged by the Scientific Computer System...

  2. Underway meteorological, navigational, optical, physical, profile and time series data collected aboard NOAA Ship Pisces in the North Atlantic Ocean from 2017-07-08 to 2017-07-26 (NCEI Accession 0165226)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NCEI Accession 0165226 contains raw underway meteorological, navigational, optical, physical, profile and time series data logged by the Scientific Computer System...

  3. Underway meteorological, navigational, optical, physical and time series data collected aboard NOAA Ship Nancy Foster in the North Atlantic Ocean from 2013-08-31 to 2013-09-07 (NODC Accession 0113487)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NODC Accession 0113487 contains raw underway meteorological, navigational, optical, physical and time series data logged by the Scientific Computer System (SCS)...

  4. Underway meteorological, navigational, optical, physical, profile and time series data collected aboard NOAA Ship Pisces in the North Atlantic Ocean from 2014-07-06 to 2014-08-02 (NODC Accession 0121197)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NODC Accession 0121197 contains raw underway meteorological, navigational, optical, physical, profile and time series data logged by the Scientific Computer System...

  5. Underway meteorological, navigational, optical, physical, profile and time series data collected aboard NOAA Ship Pisces in the North Atlantic Ocean from 2015-07-10 to 2015-08-04 (NCEI Accession 0130690)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NODC Accession 0130690 contains raw underway meteorological, navigational, optical, physical, profile and time series data logged by the Scientific Computer System...

  6. Underway meteorological, navigational, optical, physical and time series data collected aboard NOAA Ship Oscar Dyson in the Gulf of Alaska from 2017-03-01 to 2017-03-10 (NCEI Accession 0165011)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NCEI Accession 0165011 contains raw underway meteorological, navigational, optical, physical and time series data logged by the Scientific Computer System (SCS)...

  7. Underway meteorological, navigational, optical, physical and time series data collected aboard NOAA Ship Oscar Dyson in the Gulf of Alaska from 2013-03-14 to 2013-03-28 (NODC Accession 0124186)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NODC Accession 0124186 contains raw underway meteorological, navigational, optical, physical and time series data logged by the Scientific Computer System (SCS)...

  8. Underway meteorological, navigational, optical, physical and time series data collected aboard NOAA Ship Oscar Dyson in the Gulf of Alaska from 2015-03-14 to 2015-03-31 (NCEI Accession 0130691)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NODC Accession 0130691 contains raw underway meteorological, navigational, optical, physical and time series data logged by the Scientific Computer System (SCS)...

  9. Underway meteorological, navigational, optical, physical and time series data collected aboard NOAA Ship Gordon Gunter in the North Atlantic Ocean from 2016-05-21 to 2016-06-04 (NCEI Accession 0155169)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NCEI Accession 0155169 contains raw underway meteorological, navigational, optical, physical and time series data logged by the Scientific Computer System (SCS)...

  10. Underway meteorological, navigational, optical, physical and time series data collected aboard NOAA Ship Gordon Gunter in the Gulf of Mexico from 2016-09-16 to 2016-09-18 (NCEI Accession 0164081)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NCEI Accession 0164081 contains raw underway meteorological, navigational, optical, physical and time series data logged by the Scientific Computer System (SCS)...

  11. Underway meteorological, navigational, optical, physical and time series data collected aboard NOAA Ship Gordon Gunter in the Gulf of Mexico from 2016-10-31 to 2016-11-03 (NCEI Accession 0164446)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NCEI Accession 0164446 contains raw underway meteorological, navigational, optical, physical and time series data logged by the Scientific Computer System (SCS)...

  12. Underway meteorological, navigational, optical, physical and time series data collected aboard NOAA Ship Oscar Dyson in the Gulf of Alaska from 2017-03-14 to 2017-03-27 (NCEI Accession 0165012)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NCEI Accession 0165012 contains raw underway meteorological, navigational, optical, physical and time series data logged by the Scientific Computer System (SCS)...

  13. Underway meteorological, navigational, optical, physical, profile and time series data collected aboard NOAA Ship Pisces in the Gulf of Mexico from 2016-05-26 to 2016-05-31 (NCEI Accession 0155295)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NCEI Accession 0155295 contains raw underway meteorological, navigational, optical, physical, profile and time series data logged by the Scientific Computer System...

  14. Underway meteorological, navigational, optical, physical, profile and time series data collected aboard NOAA Ship Pisces in the North Atlantic Ocean from 2016-06-08 to 2016-06-25 (NCEI Accession 0155294)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NCEI Accession 0155294 contains raw underway meteorological, navigational, optical, physical, profile and time series data logged by the Scientific Computer System...

  15. Underway meteorological, navigational, optical, physical, profile and time series data collected aboard NOAA Ship Pisces in the Gulf of Mexico from 2014-08-22 to 2014-09-12 (NODC Accession 0121982)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NODC Accession 0121982 contains raw underway meteorological, navigational, optical, physical, profile and time series data logged by the Scientific Computer System...

  16. Arsenic speciation in sulfidic waters: reconciling contradictory spectroscopic and chromatographic evidence.

    Science.gov (United States)

    Planer-Friedrich, Britta; Suess, Elke; Scheinost, Andreas C; Wallschläger, Dirk

    2010-12-15

    In recent years, analytical methods have been developed that have demonstrated that soluble arsenic-sulfur species constitute a major fraction of dissolved arsenic in sulfidic waters. However, an intense debate is going on about the exact chemical nature of these compounds, since X-ray absorption spectroscopy (XAS) data generated at higher (mmol/L) concentrations suggest the presence of (oxy)thioarsenites in such waters, while ion chromatographic (IC) and mass spectroscopic data at lower (μmol/L to nmol/L) concentrations indicate the presence of (oxy)thioarsenates. In this contribution, we connect and explain these two apparently different types of results. We show by XAS that thioarsenites are the primary reaction products of arsenite and sulfide in geochemical model experiments in the complete absence of oxygen. However, thioarsenites are extremely unstable toward oxidation, and convert rapidly into thioarsenates when exposed to atmospheric oxygen, e.g., while waiting for analysis on the chromatographic autosampler. This problem can only be eliminated when the entire chromatographic process is conducted inside a glovebox. We also show that thioarsenites are unstable toward sample dilution, which is commonly employed prior to chromatographic analysis when ultrasensitive detectors like ICP-MS are used. This instability has two main reasons: if pH changes during dilution, then equilibria between individual arsenic-sulfur species rearrange rapidly due to their different stability regions within the pH range, and if pH is kept constant during dilution, then this changes the ratio between OH(-) and SH(-) in solution, which in turn shifts the underlying speciation equilibria. This problem is avoided by analyzing samples undiluted. Our studies show that thioarsenites appear as thioarsenates in IC analyses if oxygen is not excluded completely, and as arsenite if samples are diluted in alkaline anoxic medium. This also points out that thioarsenites are necessary

  17. Stereospecific high-performance liquid chromatographic assay of sotalol in plasma.

    Science.gov (United States)

    Carr, R A; Foster, R T; Bhanji, N H

    1991-09-01

    A convenient high-performance liquid chromatographic (HPLC) assay was developed for determination of sotalol (STL) enantiomers in plasma. Following addition of the internal standard (IS; racemic atenolol), enantiomers of STL and IS were extracted using ethyl acetate. After evaporation of the organic layer, samples were derivatized with a solution of S-(+)-1-(1-naphthyl)ethyl isocyanate (NEIC). The resulting diastereomers were chromatographed with normal-phase HPLC with chloroform:hexane:methanol [65:33:2 (v/v)] as the mobile phase at a flow rate of 2 ml/min. The fluorescence detection wavelength was set at 220 nm for excitation with no emission filter. The suitability of the assay for pharmacokinetic studies was determined by measuring STL enantiomers in the plasma of a healthy subject after administration of a single 160-mg oral, racemic dose of STL.

  18. A review on sample preparation and chromatographic determination of acephate and methamidophos in

    Directory of Open Access Journals (Sweden)

    Vijay Kumar

    2015-09-01

    Full Text Available Acephate and its metabolite methamidophos are common organophosphorus insecticide used for crop protection. High uses of acephate and methamidophos have induced health issues and environmental pollution. Their undesired presence in the environment is creating ecotoxicology and may harm human health. It is therefore essential to detect the presence of acephate and methamidophos even in trace level. In this review, we have tried to accommodate successful methods of detection of acephate and methamidophos in the different biological media. Their recovery and residue analysis in different media such as vegetables, human and animal tissues have also included. The most common method for their determination is based on chromatographic separation and identification. Among different chromatographic methods, LC and GC coupled with different detectors have used. But, they both need extensive pretreatment and cleanup procedure, before undergoing chromatographic separation and identification. LC coupled with mass spectrometry (LCMS is sometime able to detect acephate and methamidophos in ppm level.

  19. Underway meteorological, navigational, physical and time series data collected aboard NOAA Ship Ronald H. Brown in the North Pacific Ocean from 2016-03-29 to 2016-04-25 (NCEI Accession 0155759)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NCEI Accession 0155759 contains raw underway meteorological, navigational, physical and time series data logged by the Scientific Computer System (SCS) aboard NOAA...

  20. Underway meteorological, navigational, physical and time series data collected aboard NOAA Ship Henry B. Bigelow in the North Atlantic Ocean from 2017-07-06 to 2017-07-19 (NCEI Accession 0164783)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NCEI Accession 0164783 contains raw underway meteorological, navigational, physical and time series data logged by the Scientific Computer System (SCS) aboard NOAA...

  1. Underway meteorological, navigational, physical and time series data collected aboard NOAA Ship Henry B. Bigelow in the North Atlantic Ocean from 2015-11-12 to 2015-11-17 (NCEI Accession 0138157)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NODC Accession 0138157 contains raw underway meteorological, navigational, physical and time series data logged by the Scientific Computer System (SCS) aboard NOAA...

  2. Effects of γ-irradiation on caprolactam level from multilayer PA-6 films for food packaging: Development and validation of a gas chromatographic method

    International Nuclear Information System (INIS)

    Araujo, Henrique Peres; Felix, Juliana Silva; Manzoli, Jose Eduardo; Padula, Marisa; Monteiro, Magali

    2008-01-01

    A gas chromatographic method to determine caprolactam in multilayer PA-6 films used for meat foodstuffs and cheese was developed and validated. A wide linear range (0.8-400 μg/ml), RSD≤4.1% and recovery higher than 90.0% were obtained for the chromatographic system, while precision and accuracy of the method showed RSD≤3.8%, recovery from 95.5-100.0% and LOQ of 32 μg/g. Irradiated (3, 7 and 12 kGy) and non-irradiated commercial films were analyzed. Most of them increased caprolactam levels with the increase of irradiation doses

  3. Effects of {gamma}-irradiation on caprolactam level from multilayer PA-6 films for food packaging: Development and validation of a gas chromatographic method

    Energy Technology Data Exchange (ETDEWEB)

    Araujo, Henrique Peres; Felix, Juliana Silva [Department of Food and Nutrition, School of Pharmaceutical Science, Sao Paulo State University, PO Box 502, 14801-902 Araraquara, SP (Brazil); Manzoli, Jose Eduardo [Nuclear and Energetic Research Institute (IPEN), Sao Paulo, SP (Brazil); Padula, Marisa [Packaging Technology Center/Food Technology Institute (CETEA/ITAL), Campinas, SP (Brazil); Monteiro, Magali [Department of Food and Nutrition, School of Pharmaceutical Science, Sao Paulo State University, PO Box 502, 14801-902 Araraquara, SP (Brazil)], E-mail: monteiro@fcfar.unesp.br

    2008-07-15

    A gas chromatographic method to determine caprolactam in multilayer PA-6 films used for meat foodstuffs and cheese was developed and validated. A wide linear range (0.8-400 {mu}g/ml), RSD{<=}4.1% and recovery higher than 90.0% were obtained for the chromatographic system, while precision and accuracy of the method showed RSD{<=}3.8%, recovery from 95.5-100.0% and LOQ of 32 {mu}g/g. Irradiated (3, 7 and 12 kGy) and non-irradiated commercial films were analyzed. Most of them increased caprolactam levels with the increase of irradiation doses.

  4. Underway meteorological, navigational, optical, physical, profile and time series data collected aboard NOAA Ship Oregon II in the Gulf of Mexico from 2015-05-01 to 2015-05-31 (NCEI Accession 0129419)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NODC Accession 0129419 contains raw underway meteorological, navigational, optical, physical, profile and time series data logged by the Scientific Computer System...

  5. Underway meteorological, navigational, physical, profile and time series data collected aboard NOAA Ship Henry B. Bigelow in the North Atlantic Ocean from 2012-08-07 to 2012-08-24 (NODC Accession 0125711)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NODC Accession 0125711 contains raw underway meteorological, navigational, physical, profile and time series data logged by the Scientific Computer System (SCS)...

  6. Underway meteorological, navigational, physical, profile and time series data collected aboard NOAA Ship Henry B. Bigelow in the North Atlantic Ocean from 2013-07-01 to 2013-08-18 (NODC Accession 0115902)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NODC Accession 0115902 contains raw underway meteorological, navigational, physical, profile and time series data logged by the Scientific Computer System (SCS)...

  7. Underway meteorological, navigational, optical, physical and time series data collected aboard NOAA Ship Bell M. Shimada in the North Pacific Ocean from 2016-05-27 to 2016-05-28 (NCEI Accession 0164091)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NCEI Accession 0164091 contains raw underway meteorological, navigational, optical, physical and time series data logged by the Scientific Computer System (SCS)...

  8. Underway meteorological, navigational, optical, physical and time series data collected aboard NOAA Ship Bell M. Shimada in the North Pacific Ocean from 2016-03-23 to 2016-04-23 (NCEI Accession 0150875)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NCEI Accession 0150875 contains raw underway meteorological, navigational, optical, physical and time series data logged by the Scientific Computer System (SCS)...

  9. Underway meteorological, navigational, optical, physical, profile and time series data collected aboard NOAA Ship Gordon Gunter in the North Atlantic Ocean from 2016-06-30 to 2016-07-16 (NCEI Accession 0165361)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NCEI Accession 0165361 contains raw underway meteorological, navigational, optical, physical, profile and time series data logged by the Scientific Computer System...

  10. Underway meteorological, navigational, optical, physical, profile and time series data collected aboard NOAA Ship Oregon II in the Gulf of Mexico from 2014-06-07 to 2014-07-19 (NODC Accession 0120616)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NODC Accession 0120616 contains raw underway meteorological, navigational, optical, physical, profile and time series data logged by the Scientific Computer System...

  11. Underway meteorological, navigational, optical, physical, profile and time series data collected aboard NOAA Ship Gordon Gunter in the Gulf of Mexico from 2016-03-17 to 2016-03-22 (NCEI Accession 0150824)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NCEI Accession 0150824 contains raw underway meteorological, navigational, optical, physical, profile and time series data logged by the Scientific Computer System...

  12. Underway meteorological, navigational, optical, physical, profile and time series data collected aboard NOAA Ship Hi'ialakai in the North Pacific Ocean from 2013-09-05 to 2013-09-20 (NODC Accession 0113248)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NODC Accession 0113248 contains raw underway meteorological, navigational, optical, physical, profile and time series data logged by the Scientific Computer System...

  13. Underway meteorological, navigational, optical, physical, profile and time series data collected aboard NOAA Ship Gordon Gunter in the Gulf of Mexico from 2016-10-23 to 2016-11-22 (NCEI Accession 0164155)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NCEI Accession 0164155 contains raw underway meteorological, navigational, optical, physical, profile and time series data logged by the Scientific Computer System...

  14. Underway meteorological, navigational, optical, physical and time series data collected aboard NOAA Ship Bell M. Shimada in the North Pacific Ocean from 2017-03-29 to 2017-04-20 (NCEI Accession 0164320)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NCEI Accession 0164320 contains raw underway meteorological, navigational, optical, physical and time series data logged by the Scientific Computer System (SCS)...

  15. Underway meteorological, navigational, optical, physical, profile and time series data collected aboard NOAA Ship Gordon Gunter in the Gulf of Mexico from 2012-10-19 to 2012-10-29 (NODC Accession 0113519)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NODC Accession 0113519 contains raw underway meteorological, navigational, optical, physical, profile and time series data logged by the Scientific Computer System...

  16. Underway meteorological, navigational, optical, physical, profile and time series data collected aboard NOAA Ship Gordon Gunter in the Gulf of Mexico from 2016-09-02 to 2016-10-01 (NCEI Accession 0164082)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NCEI Accession 0164082 contains raw underway meteorological, navigational, optical, physical, profile and time series data logged by the Scientific Computer System...

  17. Underway meteorological, navigational, optical, physical, profile and time series data collected aboard NOAA Ship Oregon II in the Gulf of Mexico from 2017-06-05 to 2017-06-07 (NCEI Accession 0164786)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NCEI Accession 0164786 contains raw underway meteorological, navigational, optical, physical, profile and time series data logged by the Scientific Computer System...

  18. Underway meteorological, navigational, physical, profile and time series data collected aboard NOAA Ship Henry B. Bigelow in the North Atlantic Ocean from 2014-07-24 to 2014-07-30 (NODC Accession 0125266)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NODC Accession 0125266 contains raw underway meteorological, navigational, physical, profile and time series data logged by the Scientific Computer System (SCS)...

  19. Underway meteorological, navigational, physical, profile and time series data collected aboard NOAA Ship Henry B. Bigelow in the North Atlantic Ocean from 2015-08-12 to 2015-08-21 (NCEI Accession 0131861)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NODC Accession 0131861 contains raw underway meteorological, navigational, physical, profile and time series data logged by the Scientific Computer System (SCS)...

  20. Underway meteorological, navigational, optical, physical and time series data collected aboard NOAA Ship Oscar Elton Sette in the North Pacific Ocean from 2017-03-29 to 2017-04-07 (NCEI Accession 0164431)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NCEI Accession 0164431 contains raw underway meteorological, navigational, optical, physical and time series data logged by the Scientific Computer System (SCS)...

  1. Underway meteorological, navigational, optical, physical, profile and time series data collected aboard NOAA Ship Oregon II in the Gulf of Mexico from 2016-03-31 to 2016-04-22 (NCEI Accession 0150823)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NCEI Accession 0150823 contains raw underway meteorological, navigational, optical, physical, profile and time series data logged by the Scientific Computer System...

  2. Underway meteorological, navigational, optical, physical and time series data collected aboard NOAA Ship Oscar Elton Sette in the North Pacific Ocean from 2014-09-25 to 2014-10-27 (NODC Accession 0123056)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NODC Accession 0123056 contains raw underway meteorological, navigational, optical, physical and time series data logged by the Scientific Computer System (SCS)...

  3. Underway meteorological, navigational, physical, profile and time series data collected aboard NOAA Ship Henry B. Bigelow in the North Atlantic Ocean from 2015-05-19 to 2015-06-03 (NCEI Accession 0129421)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NODC Accession 0129421 contains raw underway meteorological, navigational, physical, profile and time series data logged by the Scientific Computer System (SCS)...

  4. Underway meteorological, navigational, optical, physical and time series data collected aboard NOAA Ship Oscar Elton Sette in the North Pacific Ocean from 2014-08-30 to 2014-09-19 (NCEI Accession 0123092)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NODC Accession 0123092 contains raw underway meteorological, navigational, optical, physical and time series data logged by the Scientific Computer System (SCS)...

  5. Underway meteorological, navigational, optical, physical and time series data collected aboard NOAA Ship Oscar Elton Sette in the North Pacific Ocean from 2016-06-13 to 2016-06-22 (NCEI Accession 0155171)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NCEI Accession 0155171 contains raw underway meteorological, navigational, optical, physical and time series data logged by the Scientific Computer System (SCS)...

  6. Underway meteorological, navigational, optical, physical and time series data collected aboard NOAA Ship Bell M. Shimada in the North Pacific Ocean from 2017-04-27 to 2017-05-11 (NCEI Accession 0164342)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NCEI Accession 0164342 contains raw underway meteorological, navigational, optical, physical and time series data logged by the Scientific Computer System (SCS)...

  7. Underway meteorological, navigational, physical, profile and time series data collected aboard NOAA Ship Henry B. Bigelow in the North Atlantic Ocean from 2012-05-31 to 2012-06-14 (NODC Accession 0125709)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NODC Accession 0125709 contains raw underway meteorological, navigational, physical, profile and time series data logged by the Scientific Computer System (SCS)...

  8. Underway meteorological, navigational, optical, physical, profile and time series data collected aboard NOAA Ship Gordon Gunter in the North Atlantic Ocean from 2017-06-10 to 2017-06-23 (NCEI Accession 0164441)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NCEI Accession 0164441 contains raw underway meteorological, navigational, optical, physical, profile and time series data logged by the Scientific Computer System...

  9. Underway meteorological, navigational, physical, profile and time series data collected aboard NOAA Ship Henry B. Bigelow in the North Atlantic Ocean from 2012-02-27 to 2012-05-04 (NODC Accession 0125710)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NODC Accession 0125710 contains raw underway meteorological, navigational, physical, profile and time series data logged by the Scientific Computer System (SCS)...

  10. Underway meteorological, navigational, physical, profile and time series data collected aboard NOAA Ship Henry B. Bigelow in the North Atlantic Ocean from 2015-07-27 to 2015-08-07 (NCEI Accession 0130538)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NODC Accession 0130538 contains raw underway meteorological, navigational, physical, profile and time series data logged by the Scientific Computer System (SCS)...

  11. Underway meteorological, navigational, physical, profile and time series data collected aboard NOAA Ship Henry B. Bigelow in the North Atlantic Ocean from 2014-08-05 to 2014-08-16 (NODC Accession 0125265)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NODC Accession 0125265 contains raw underway meteorological, navigational, physical, profile and time series data logged by the Scientific Computer System (SCS)...

  12. Underway meteorological, navigational, physical, profile and time series data collected aboard NOAA Ship Henry B. Bigelow in the North Atlantic Ocean from 2017-06-08 to 2017-06-22 (NCEI Accession 0164795)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NCEI Accession 0164795 contains raw underway meteorological, navigational, physical, profile and time series data logged by the Scientific Computer System (SCS)...

  13. Underway meteorological, navigational, physical, profile and time series data collected aboard NOAA Ship Henry B. Bigelow in the North Atlantic Ocean from 2015-05-19 to 2015-06-03 (NCEI Accession 0134847)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NODC Accession 0134847 contains raw underway meteorological, navigational, physical, profile and time series data logged by the Scientific Computer System (SCS)...

  14. Underway meteorological, navigational, physical, profile and time series data collected aboard NOAA Ship Henry B. Bigelow in the North Atlantic Ocean from 2014-06-18 to 2014-07-01 (NODC Accession 0125584)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NODC Accession 0125584 contains raw underway meteorological, navigational, physical, profile and time series data logged by the Scientific Computer System (SCS)...

  15. Underway meteorological, navigational, physical, profile and time series data collected aboard NOAA Ship Henry B. Bigelow in the North Atlantic Ocean from 2013-06-10 to 2013-06-24 (NODC Accession 0115702)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NODC Accession 0115702 contains raw underway meteorological, navigational, physical, profile and time series data logged by the Scientific Computer System (SCS)...

  16. Underway meteorological, navigational, physical, profile and time series data collected aboard NOAA Ship Henry B. Bigelow in the North Atlantic Ocean from 2012-06-18 to 2012-06-28 (NODC Accession 0125666)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NODC Accession 0125666 contains raw underway meteorological, navigational, physical, profile and time series data logged by the Scientific Computer System (SCS)...

  17. Underway meteorological, navigational, physical, profile and time series data collected aboard NOAA Ship Henry B. Bigelow in the North Atlantic Ocean from 2012-07-04 to 2012-07-18 (NODC Accession 0125758)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NODC Accession 0125758 contains raw underway meteorological, navigational, physical, profile and time series data logged by the Scientific Computer System (SCS)...

  18. Underway meteorological, navigational, physical, profile and time series data collected aboard NOAA Ship Henry B. Bigelow in the North Atlantic Ocean from 2012-09-04 to 2012-11-11 (NODC Accession 0125919)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NODC Accession 0125919 contains raw underway meteorological, navigational, physical, profile and time series data logged by the Scientific Computer System (SCS)...

  19. Underway meteorological, navigational, physical, profile and time series data collected aboard NOAA Ship Henry B. Bigelow in the North Atlantic Ocean from 2016-07-18 to 2016-08-25 (NCEI Accession 0162239)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NCEI Accession 0162239 contains raw underway meteorological, navigational, physical, profile and time series data logged by the Scientific Computer System (SCS)...

  20. Underway meteorological, navigational, physical, profile and time series data collected aboard NOAA Ship Henry B. Bigelow in the North Atlantic Ocean from 2013-03-14 to 2013-05-09 (NODC Accession 0115052)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NODC Accession 0115052 contains raw underway meteorological, navigational, physical, profile and time series data logged by the Scientific Computer System (SCS)...

  1. Underway meteorological, navigational, physical, profile and time series data collected aboard NOAA Ship Henry B. Bigelow in the North Atlantic Ocean from 2015-06-10 to 2015-07-02 (NCEI Accession 0129527)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NODC Accession 0129527 contains raw underway meteorological, navigational, physical, profile and time series data logged by the Scientific Computer System (SCS)...

  2. Underway meteorological, navigational, optical, physical, profile and time series data collected aboard NOAA Ship Oregon II in the Gulf of Mexico from 2017-03-20 to 2017-04-20 (NCEI Accession 0164319)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NCEI Accession 0164319 contains raw underway meteorological, navigational, optical, physical, profile and time series data logged by the Scientific Computer System...

  3. Underway meteorological, navigational, optical, physical, profile and time series data collected aboard NOAA Ship Oregon II in the Gulf of Mexico from 2013-10-24 to 2013-11-22 (NODC Accession 0116135)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NODC Accession 0116135 contains raw underway meteorological, navigational, optical, physical, profile and time series data logged by the Scientific Computer System...

  4. Underway meteorological, navigational, optical, physical and time series data collected aboard NOAA Ship Bell M. Shimada in the North Pacific Ocean from 2013-01-11 to 2013-02-02 (NCEI Accession 0115911)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NODC Accession 0115911 contains raw underway meteorological, navigational, optical, physical and time series data logged by the Scientific Computer System (SCS)...

  5. Underway meteorological, navigational, optical, physical, profile and time series data collected aboard NOAA Ship Oregon II in the Gulf of Mexico from 2015-10-08 to 2015-11-21 (NCEI Accession 0138304)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NODC Accession 0138304 contains raw underway meteorological, navigational, optical, physical, profile and time series data logged by the Scientific Computer System...

  6. Underway meteorological, navigational, optical, physical, profile and time series data collected aboard NOAA Ship Oregon II in the Gulf of Mexico from 2016-04-29 to 2016-05-31 (NCEI Accession 0152488)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NCEI Accession 0152488 contains raw underway meteorological, navigational, optical, physical, profile and time series data logged by the Scientific Computer System...

  7. Underway meteorological, navigational, optical, physical, profile and time series data collected aboard NOAA Ship Oregon II in the Gulf of Mexico from 2017-04-28 to 2017-05-30 (NCEI Accession 0164785)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NCEI Accession 0164785 contains raw underway meteorological, navigational, optical, physical, profile and time series data logged by the Scientific Computer System...

  8. Optimizing Chromatographic Separation: An Experiment Using an HPLC Simulator

    Science.gov (United States)

    Shalliker, R. A.; Kayillo, S.; Dennis, G. R.

    2008-01-01

    Optimization of a chromatographic separation within the time constraints of a laboratory session is practically impossible. However, by employing a HPLC simulator, experiments can be designed that allow students to develop an appreciation of the complexities involved in optimization procedures. In the present exercise, a HPLC simulator from "JCE…

  9. Bioanalytical method transfer considerations of chromatographic-based assays.

    Science.gov (United States)

    Williard, Clark V

    2016-07-01

    Bioanalysis is an important part of the modern drug development process. The business practice of outsourcing and transferring bioanalytical methods from laboratory to laboratory has increasingly become a crucial strategy for successful and efficient delivery of therapies to the market. This chapter discusses important considerations when transferring various types of chromatographic-based assays in today's pharmaceutical research and development environment.

  10. Chromatographic separation and spectro-analytical characterization of a natural African mineral dye

    Directory of Open Access Journals (Sweden)

    G.B. Adebayo

    2007-08-01

    Full Text Available Chromatographic fractionation and spectroscopic characterization of a natural African mineral dye have been carried out. The chromatographic separation of the dyes made use of column and thin layer chromatographic techniques. Some physicochemical properties of the dye including solubility in polar and non-polar solvents, pH, ash and organic contents were determined. The spectro-analytical techniques used for characterization included energy dispersive X-ray fluorescence (EDXRF, X-ray diffractometry (XRD, Optical microscopy, infrared (IR and UV-VIS spectroscopy. Four different fractions having colours yellow, grey, orange and purple were obtained from the chromatographic separation. All the fractions were found to contain aromatic nucleus based on IR and UV-VIS spectroscopic data. Other functional groups detected are Ar-NH2, -CONH2, C=C, C-C and metal-carbon chelate rings. The presence of aromatic amine in the dye provides strong evidence for its use as hair dye. The dye was found to be soluble in both aqueous and non-aqueous solvents. The pH of the dye's aqueous solution was found to be 8.6, and the ash and organic content of the raw dye were 49 % and 51 % respectively. The XRF revealed that the dye contains twenty elements with concentrations ranging from major to ultra-trace levels. The XRD also showed that the sample contains about forty-six mineral phases which include both inorganic and organic components. The maximum absorption wavelength (λmax in UV-VIS of the aqueous solution was found to be 464 nm. The optical microscopic investigation gave indication that the dyes are likely to be of the marine origin.

  11. Aspect-dependent radiated noise analysis of an underway autonomous underwater vehicle.

    Science.gov (United States)

    Gebbie, John; Siderius, Martin; Allen, John S

    2012-11-01

    This paper presents an analysis of the acoustic emissions emitted by an underway REMUS-100 autonomous underwater vehicle (AUV) that were obtained near Honolulu Harbor, HI using a fixed, bottom-mounted horizontal line array (HLA). Spectral analysis, beamforming, and cross-correlation facilitate identification of independent sources of noise originating from the AUV. Fusion of navigational records from the AUV with acoustic data from the HLA allows for an aspect-dependent presentation of calculated source levels of the strongest propulsion tone.

  12. Measurement of water absorption capacity in wheat flour by a headspace gas chromatographic technique.

    Science.gov (United States)

    Xie, Wei-Qi; Yu, Kong-Xian; Gong, Yi-Xian

    2018-04-17

    The purpose of this work is to introduce a new method for quantitatively analyzing water absorption capacity in wheat flour by a headspace gas chromatographic technique. This headspace gas chromatographic technique was based on measuring the water vapor released from a series of wheat flour samples with different contents of water addition. According to the different trends between the vapor and wheat flour phase before and after the water absorption capacity in wheat flour, a turning point (corresponding to water absorption capacity in wheat flour) can be obtained by fitting the data of the water gas chromatography peak area from different wheat flour samples. The data showed that the phase equilibrium in the vial can be achieved in 25 min at desired temperature (35°C). The relative standard deviation of the reaction headspace gas chromatographic technique in water absorption capacity determination was within 3.48%, the relative differences has been determined by comparing the water absorption capacity obtained from this new analytical technique with the data from the reference technique (i.e., the filtration method), which are less than 8.92%. The new headspace gas chromatographic method is automated, accurate and be a reliable tool for quantifying water absorption capacity in wheat flour in both laboratory research and mill applications. © 2018 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  13. Proposal for data acquisition system of gas chromatograph and natural gas transfer custody via web; Proposta para um sistema de aquisicao de dados de cromatografia e medicao fiscal de gas natural via web

    Energy Technology Data Exchange (ETDEWEB)

    Santana, Jose Paulo C.; Guimaraes, Marcelo F.; Zeitoune, Rafael J. [PETROBRAS, Rio de Janeiro, RJ (Brazil)

    2005-07-01

    In this paper, is presented a proposal of a Chromatograph and Transfer Custody Measurement Data Acquisition System through Web, complementary to the SCADA System, responsible for control and monitoring PETROBRAS Gas Pipelines, intended to comply with the requirements of the Gerencias de Qualidade e Medicao (MQD) and Planejamento Integrado da Logistica (PCL) from PETROBRAS Gas e Energia, regarding the evaluation of the quality of the natural gas that is being commercialized, as well as its billing. (author)

  14. Reverse-Phase High-Performance Liquid Chromatographic Separation of Methylated and Non-Methylated Nucleic Acid Bases

    OpenAIRE

    Madyastha, Prema; Rao, Pratima; Deobagkar, DN; Madyastha, KM

    1983-01-01

    A high-performance liquid chromatographic sepration method is described for the detection of 5-methylcytosine and 6-methyladenine in nucleic acid ext. The bases were sepd. on a Waters $C18 \\mu$ Bondapak column with a water: methanol acetic acid system. Effluents were monitored by UV absorption at 254 nm. The bases were estd. by peak heights which are proportional to the amts. of the individual bases. The method is rapid, sensitive, easy to perform and reproducible.

  15. Chemiluminescent Determination of Oxamyl in Drinking Water and Tomato Using Online Postcolumn UV Irradiation in a Chromatographic System.

    Science.gov (United States)

    Murillo Pulgarín, José A; García Bermejo, Luisa F; Durán, Armando Carrasquero

    2018-03-07

    High-performance liquid chromatography (HPLC) was used to separate oxamyl from other pesticides in drinking water and tomato paste. The eluate emerging from the column tail was mixed with an alkaline solution of Co 2+ in EDTA and irradiated with UV light to induce photolysis of the carbamate in order to obtain free radicals and other reactive species that oxidize luminol and produce chemiluminescence (CL) as a result. The intensity of the CL signal was monitored in the form of chromatographic peaks. Under the optimum operating conditions for the HPLC-UV-CL system, the analyte concentration was linearly related to peak area. The limit of detection as determined in accordance with the IUPAC criterion was 0.17 mg L -1 . Oxamyl was successfully extracted with recoveries of 88.7-103.1% from spiked tomato paste by using a simple QuEChERS (Quick, Easy, Cheap, Effective, Rugged, and Safe) sample preparation approach. Similar recoveries were obtained from drinking water samples spiked with oxamyl concentrations above the LOD. The proposed method is a simple, fast, accurate choice for quantifying this pesticide.

  16. Underway meteorological, navigational, optical, physical, profile and time series data collected aboard NOAA Ship Bell M. Shimada in the North Pacific Ocean from 2016-04-28 to 2016-05-09 (NCEI Accession 0151241)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NCEI Accession 0151241 contains raw underway meteorological, navigational, optical, physical, profile and time series data logged by the Scientific Computer System...

  17. Underway meteorological, navigational, optical, physical, profile and time series data collected aboard NOAA Ship Bell M. Shimada in the North Pacific Ocean from 2017-05-15 to 2017-05-24 (NCEI Accession 0164430)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NCEI Accession 0164430 contains raw underway meteorological, navigational, optical, physical, profile and time series data logged by the Scientific Computer System...

  18. Underway meteorological, navigational, optical, physical, profile and time series data collected aboard NOAA Ship Bell M. Shimada in the North Pacific Ocean from 2015-01-31 to 2015-02-04 (NODC Accession 0125756)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NODC Accession 0125756 contains raw underway meteorological, navigational, optical, physical, profile and time series data logged by the Scientific Computer System...

  19. Underway meteorological, navigational, optical, physical, profile and time series data collected aboard NOAA Ship Bell M. Shimada in the North Pacific Ocean from 2015-03-07 to 2015-03-22 (NODC Accession 0126660)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NODC Accession 0126660 contains raw underway meteorological, navigational, optical, physical, profile and time series data logged by the Scientific Computer System...

  20. Underway meteorological, navigational, optical, physical, profile and time series data collected aboard NOAA Ship Bell M. Shimada in the North Pacific Ocean from 2015-05-05 to 2015-05-18 (NCEI Accession 0128172)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NODC Accession 0128172 contains raw underway meteorological, navigational, optical, physical, profile and time series data logged by the Scientific Computer System...

  1. Underway meteorological, navigational, optical, physical, time series and trawl data collected aboard NOAA Ship Bell M. Shimada in the North Pacific Ocean from 2013-04-06 to 2013-04-30 (NCEI Accession 0115912)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NODC Accession 0115912 contains raw underway meteorological, navigational, optical, physical, time series and trawl data logged by the Scientific Computer System...

  2. Underway meteorological, navigational, optical, physical, profile and time series data collected aboard NOAA Ship Bell M. Shimada in the North Pacific Ocean from 2016-01-09 to 2016-02-09 (NCEI Accession 0150817)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NCEI Accession 0150817 contains raw underway meteorological, navigational, optical, physical, profile and time series data logged by the Scientific Computer System...

  3. Underway meteorological, navigational, optical, physical, profile and time series data collected aboard NOAA Ship Bell M. Shimada in the North Pacific Ocean from 2015-10-06 to 2015-10-13 (NCEI Accession 0164861)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NCEI Accession 0164861 contains raw underway meteorological, navigational, optical, physical, profile and time series data logged by the Scientific Computer System...

  4. Underway meteorological, navigational, optical, physical, profile and time series data collected aboard NOAA Ship Bell M. Shimada in the North Pacific Ocean from 2014-04-15 to 2014-05-12 (NODC Accession 0118545)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NODC Accession 0118545 contains raw underway meteorological, navigational, optical, physical, profile and time series data logged by the Scientific Computer System...

  5. Underway meteorological, navigational, optical, physical, profile and time series data collected aboard NOAA Ship Oscar Elton Sette in the North Pacific Ocean from 2015-04-03 to 2015-04-15 (NCEI Accession 0130368)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NODC Accession 0130368 contains raw underway meteorological, navigational, optical, physical, profile and time series data logged by the Scientific Computer System...

  6. Underway meteorological, navigational, optical, physical, profile and time series data collected aboard NOAA Ship Bell M. Shimada in the North Pacific Ocean from 2016-05-14 to 2016-05-28 (NCEI Accession 0164090)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NCEI Accession 0164090 contains raw underway meteorological, navigational, optical, physical, profile and time series data logged by the Scientific Computer System...

  7. Underway meteorological, navigational, optical, physical and time series data collected aboard NOAA Ship Oscar Dyson in the Coastal Waters of SE Alaska from 2016-01-30 to 2016-02-01 (NCEI Accession 0150695)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NCEI Accession 0150695 contains raw underway meteorological, navigational, optical, physical and time series data logged by the Scientific Computer System (SCS)...

  8. Underway meteorological, navigational, optical, physical, profile and time series data collected aboard NOAA Ship Bell M. Shimada in the North Pacific Ocean from 2015-05-29 to 2015-06-10 (NCEI Accession 0129494)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NODC Accession 0129494 contains raw underway meteorological, navigational, optical, physical, profile and time series data logged by the Scientific Computer System...

  9. Underway meteorological, navigational, optical, physical, profile and time series data collected aboard NOAA Ship Bell M. Shimada in the North Pacific Ocean from 2013-03-01 to 2013-03-10 (NODC Accession 0116096)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NODC Accession 0116096 contains raw underway meteorological, navigational, optical, physical, profile and time series data logged by the Scientific Computer System...

  10. Underway meteorological, navigational, optical, physical, profile and time series data collected aboard NOAA Ship Bell M. Shimada in the North Pacific Ocean from 2014-09-25 to 2014-09-30 (NCEI Accession 0136936)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NODC Accession 0136936 contains raw underway meteorological, navigational, optical, physical, profile and time series data logged by the Scientific Computer System...

  11. Underway meteorological, navigational, optical, physical, profile and time series data collected aboard NOAA Ship Bell M. Shimada in the North Pacific Ocean from 2017-02-17 to 2017-02-25 (NCEI Accession 0164313)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NCEI Accession 0164313 contains raw underway meteorological, navigational, optical, physical, profile and time series data logged by the Scientific Computer System...

  12. Gas chromatographic analysis of simmondsins and simmondsin ferulates in jojoba meal.

    Science.gov (United States)

    Van Boven, M; Holser, R; Cokelaere, M; Flo, G; Decuypere, E

    2000-09-01

    A capillary gas chromatographic method was developed for the simultaneous determination of simmondsins and simmondsin ferulates in jojoba meal, in detoxified jojoba meal, in jojoba meal extracts, and in animal food mixtures.

  13. Enhanced binding by dextran-grafting to Protein A affinity chromatographic media.

    Science.gov (United States)

    Zhao, Lan; Zhu, Kai; Huang, Yongdong; Li, Qiang; Li, Xiunan; Zhang, Rongyue; Su, Zhiguo; Wang, Qibao; Ma, Guanghui

    2017-04-01

    Dextran-grafted Protein A affinity chromatographic medium was prepared by grafting dextran to agarose-based matrix, followed by epoxy-activation and Protein A coupling site-directed to sulfhydryl groups of cysteine molecules. An enhancement of both the binding performance and the stability was achieved for this dextran-grafted Protein A chromatographic medium. Its dynamic binding capacity was 61 mg immunoglobulin G/mL suction-dried gel, increased by 24% compared with that of the non-grafted medium. The binding capacity of dextran-grafted medium decreased about 7% after 40 cleaning-in-place cycles, much lower than that of the non-grafted medium as decreased about 15%. Confocal laser scanning microscopy results showed that immunoglobulin G was bound to both the outside and the inside of dextran-grafted medium faster than that of non-grafted one. Atomic force microscopy showed that this dextran-grafted Protein A medium had much rougher surface with a vertical coordinate range of ±80 nm, while that of non-grafted one was ±10 nm. Grafted dextran provided a more stereo surface morphology and immunoglobulin G molecules were more easily to be bound. This high-performance dextran-grafted Protein A affinity chromatographic medium has promising applications in large-scale antibody purification. © 2017 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  14. Similarity analyses of chromatographic herbal fingerprints: A review

    International Nuclear Information System (INIS)

    Goodarzi, Mohammad; Russell, Paul J.; Vander Heyden, Yvan

    2013-01-01

    Graphical abstract: -- Highlights: •Similarity analyses of herbal fingerprints are reviewed. •Different (dis)similarity approaches are discussed. •(Dis)similarity-metrics and exploratory-analysis approaches are illustrated. •Correlation and distance-based measures are overviewed. •Similarity analyses illustrated by several case studies. -- Abstract: Herbal medicines are becoming again more popular in the developed countries because being “natural” and people thus often assume that they are inherently safe. Herbs have also been used worldwide for many centuries in the traditional medicines. The concern of their safety and efficacy has grown since increasing western interest. Herbal materials and their extracts are very complex, often including hundreds of compounds. A thorough understanding of their chemical composition is essential for conducting a safety risk assessment. However, herbal material can show considerable variability. The chemical constituents and their amounts in a herb can be different, due to growing conditions, such as climate and soil, the drying process, the harvest season, etc. Among the analytical methods, chromatographic fingerprinting has been recommended as a potential and reliable methodology for the identification and quality control of herbal medicines. Identification is needed to avoid fraud and adulteration. Currently, analyzing chromatographic herbal fingerprint data sets has become one of the most applied tools in quality assessment of herbal materials. Mostly, the entire chromatographic profiles are used to identify or to evaluate the quality of the herbs investigated. Occasionally only a limited number of compounds are considered. One approach to the safety risk assessment is to determine whether the herbal material is substantially equivalent to that which is either readily consumed in the diet, has a history of application or has earlier been commercialized i.e. to what is considered as reference material. In order

  15. Similarity analyses of chromatographic herbal fingerprints: A review

    Energy Technology Data Exchange (ETDEWEB)

    Goodarzi, Mohammad [Department of Analytical Chemistry and Pharmaceutical Technology, Center for Pharmaceutical Research, Vrije Universiteit Brussel, Laarbeeklaan 103, B-1090 Brussels (Belgium); Russell, Paul J. [Safety and Environmental Assurance Centre, Unilever, Colworth Science Park, Sharnbrook, Bedfordshire MK44 1LQ (United Kingdom); Vander Heyden, Yvan, E-mail: yvanvdh@vub.ac.be [Department of Analytical Chemistry and Pharmaceutical Technology, Center for Pharmaceutical Research, Vrije Universiteit Brussel, Laarbeeklaan 103, B-1090 Brussels (Belgium)

    2013-12-04

    Graphical abstract: -- Highlights: •Similarity analyses of herbal fingerprints are reviewed. •Different (dis)similarity approaches are discussed. •(Dis)similarity-metrics and exploratory-analysis approaches are illustrated. •Correlation and distance-based measures are overviewed. •Similarity analyses illustrated by several case studies. -- Abstract: Herbal medicines are becoming again more popular in the developed countries because being “natural” and people thus often assume that they are inherently safe. Herbs have also been used worldwide for many centuries in the traditional medicines. The concern of their safety and efficacy has grown since increasing western interest. Herbal materials and their extracts are very complex, often including hundreds of compounds. A thorough understanding of their chemical composition is essential for conducting a safety risk assessment. However, herbal material can show considerable variability. The chemical constituents and their amounts in a herb can be different, due to growing conditions, such as climate and soil, the drying process, the harvest season, etc. Among the analytical methods, chromatographic fingerprinting has been recommended as a potential and reliable methodology for the identification and quality control of herbal medicines. Identification is needed to avoid fraud and adulteration. Currently, analyzing chromatographic herbal fingerprint data sets has become one of the most applied tools in quality assessment of herbal materials. Mostly, the entire chromatographic profiles are used to identify or to evaluate the quality of the herbs investigated. Occasionally only a limited number of compounds are considered. One approach to the safety risk assessment is to determine whether the herbal material is substantially equivalent to that which is either readily consumed in the diet, has a history of application or has earlier been commercialized i.e. to what is considered as reference material. In order

  16. Chromatographic fingerprinting: An innovative approach for food 'identitation' and food authentication - A tutorial.

    Science.gov (United States)

    Cuadros-Rodríguez, Luis; Ruiz-Samblás, Cristina; Valverde-Som, Lucia; Pérez-Castaño, Estefanía; González-Casado, Antonio

    2016-02-25

    Fingerprinting methods describe a variety of analytical methods that provide analytical signals related to the composition of foodstuffs in a non-selective way such as by collecting a spectrum or a chromatogram. Mathematical processing of the information in such fingerprints may allow the characterisation and/or authentication of foodstuffs. In this context, the particular meaning of 'fingerprinting', in conjunction with 'profiling', is different from the original meanings used in metabolomics. This fact has produced some confusion with the use of these terms in analytical papers. Researchers coming from the metabolomic field could use 'profiling' or 'fingerprinting' on a different way to researchers who are devoted to food science. The arrival of an eclectic discipline, named 'foodomics' has not been enough to allay this terminological problem, since the authors keep on using the terms with both meanings. Thus, a first goal of this tutorial is to clarify the difference between both terms. In addition, the chemical approaches for food authentication, i.e., chemical markers, component profiling and instrumental fingerprinting, have been described. A new term, designated as 'food identitation', has been introduced in order to complete the life cycle of the chemical-based food authentication process. Chromatographic fingerprinting has been explained in detail and some strategies which could be applied has been clarified and discussed. Particularly, the strategies for chromatographic signals acquisition and chromatographic data handling are unified in a single framework. Finally, an overview about the applications of chromatographic (GC and LC) fingerprints in food authentication using different chemometric techniques has been included. Copyright © 2016 Elsevier B.V. All rights reserved.

  17. Automated chromatographic system with polarimetric detection laser applied in the control of fermentation processes and seaweed extracts characterization

    International Nuclear Information System (INIS)

    Fajer, V.; Naranjo, S.; Mora, W.; Patinno, R.; Coba, E.; Michelena, G.

    2012-01-01

    There are presented applications and innovations of chromatographic and polarimetric systems in which develop methodologies for measuring the input molasses and the resulting product of a fermentation process of alcohol from a rich honey and evaluation of the fermentation process honey servery in obtaining a drink native to the Yucatan region. Composition was assessed optically active substances in seaweed, of interest to the pharmaceutical industry. The findings provide measurements alternative raw materials and products of the sugar industry, beekeeping and pharmaceutical liquid chromatography with automated polarimetric detection reduces measurement times up to 15 min, making it comparable to the times of high chromatography resolution, significantly reducing operating costs. By chromatography system with polarimetric detection (SCDP) is new columns have included standard size designed by the authors, which allow process samples with volumes up to 1 ml and reduce measurement time to 15 min, decreasing to 5 times the volume sample and halving the time of measurement. Was evaluated determining the concentration of substances using the peaks of the chromatograms obtained for the different columns and calculate the uncertainty of measurements. The results relating to the improvement of a data acquisition program (ADQUIPOL v.2.0) and new programs for the preparation of chromatograms (CROMAPOL CROMAPOL V.1.0 and V.1.2) provide important benefits, which allow a considerable saving of time the processing of the results and can be applied in other chromatography systems with the appropriate adjustments. (Author)

  18. Simple gas chromatographic method for furfural analysis.

    Science.gov (United States)

    Gaspar, Elvira M S M; Lopes, João F

    2009-04-03

    A new, simple, gas chromatographic method was developed for the direct analysis of 5-hydroxymethylfurfural (5-HMF), 2-furfural (2-F) and 5-methylfurfural (5-MF) in liquid and water soluble foods, using direct immersion SPME coupled to GC-FID and/or GC-TOF-MS. The fiber (DVB/CAR/PDMS) conditions were optimized: pH effect, temperature, adsorption and desorption times. The method is simple and accurate (RSDfurfurals will contribute to characterise and quantify their presence in the human diet.

  19. Gas-liquid chromatographic determination of resmethrin in corn, cornmeal, flour, and wheat.

    Science.gov (United States)

    Simonaitis, R A; Cail, R S

    1975-09-01

    A gas-liquid chromatographic (GLC) method was developed for the determination of residues of resmethrin ((5-benzyl-3-furyl)methyl cis-trans-(+/-)-2,2-dimethyl-3-(2-methylpropenyl)-cyclopropanecarboxylate) in corn, cornmeal, flour, and wheat. The commodity, fortified with resmethrin, was extracted by tumbling with pentane and transferred to acetonitrile, the fat was partitioned off, and the sample was chromatographed with 3% ethyl acetate in pentane on Florisil containing 0.5% water. The resmethrin residue was determined by GLC with a flame ionization detector. The results were compared with known standards that had undergone the same cleanup procedures. The method was sensitive to concentrations of resmethrin to 0.2 ppm, recoveries averaged 83%, and reproducibility was good.

  20. Coffee contains cholinomimetic compound distinct from caffeine. I: Purification and chromatographic analysis.

    Science.gov (United States)

    Tse, S Y

    1991-07-01

    Both regular and decaffeinated coffees were found to have cholinomimetic actions when tested in urethane-anesthetized rats. These actions were distinct from those of caffeine and reversible by atropine. The bioactive fraction was purified from alcoholic extracts of instant decaffeinated coffee by liquid column chromatography and preparative TLC. The purified compound showed similar pharmacological actions as the starting material. Chromatographic behavior was further characterized by analytical TLC and HPLC. Chromatographic analyses of extracts of green coffee beans and roasted ground coffees showed that the cardioactive compound was only present in roasted coffees. Similar analyses of other commonly consumed beverages, including teas and cocoa, showed that this compound was not present in beverages besides coffee.

  1. Domestic Preparedness Program: Evaluation of the Agilent Gas Chromatograph - Flame Photometric Detector/Mass Selective Detector (GC-FPD/MSD) System Against Chemical Warfare Agents Summary Report

    National Research Council Canada - National Science Library

    Longworth, Terri

    2003-01-01

    This report characterizes the chemical warfare agent (CWA) detection potential of the commercially available Agilent gas chromatograph-flame photometric detector/mass selective detector (GC-FPD/MSD...

  2. Comparison of twin-cell centrifugal partition chromatographic columns with different cell volume.

    Science.gov (United States)

    Goll, Johannes; Audo, Gregoire; Minceva, Mirjana

    2015-08-07

    Two twin-cell centrifugal partition chromatographic columns (SCPC 250 and SCPE-250-BIO, Armen Instrument, France) with the same column volume but different cell size and number were compared in terms of stationary phase retention and column efficiency. The columns were tested with two types of solvent systems: a commonly used organic solvent based biphasic system from the ARIZONA solvent system family and a polymer/salt based aqueous two phase system (ATPS). The efficiency of the columns was evaluated by pulse injection experiments of two benzenediols (pyrocatechol and hydroquinone) in the case of the ARIZONA system and a protein mixture (myoglobin and lysozyme) in the case of the ATPS. As result of high stationary phase retention, the column with the lower number of larger twin-cells (SCPE-250-BIO) is suitable for protein separations using ATPS. On the other hand, due to higher column efficiency, the column with the greater number of smaller cells (SCPC 250) is superior for batch elution separations performed with standard liquid-liquid chromatography organic solvent based biphasic systems. Copyright © 2015 Elsevier B.V. All rights reserved.

  3. Underway meteorological, navigational, optical, physical and time series data collected aboard NOAA Ship Pisces in the Gulf of Mexico and North Atlantic Ocean from 2013-04-05 to 2013-06-07 (NODC Accession 0117812)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NODC Accession 0117812 contains raw underway meteorological, navigational, optical, physical and time series data logged by the Scientific Computer System (SCS)...

  4. Underway meteorological, navigational, physical, profile and time series data collected aboard NOAA Ship Hi'ialakai in the North Pacific Ocean and Philippine Sea from 2014-03-05 to 2014-06-02 (NODC Accession 0119156)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NODC Accession 0119156 contains raw underway meteorological, navigational, physical, profile and time series data logged by the Scientific Computer System (SCS)...

  5. Underway meteorological, navigational, physical, profile and time series data collected aboard NOAA Ship Hi'ialakai in the North Pacific Ocean and Philippine Sea from 2014-05-11 to 2014-05-22 (NODC Accession 0119200)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NODC Accession 0119200 contains raw underway meteorological, navigational, physical, profile and time series data logged by the Scientific Computer System (SCS)...

  6. Impurity analysis in EC-99mTC radiotracer using chromatographic techniques

    International Nuclear Information System (INIS)

    Almeida, E.V.; Fukumori, N.T.O.; Mengatti, J.; Silva, C.P.G.; Matsuda, M.M.N.

    2008-01-01

    The objective of this study was to develop two chromatographic methods of impurity analysis in radiotracer 99m Tc-EC: the Thin Layer Chromatography (TLC) and the High Performance Liquid Chromatography Reversed Phase (HPLC-RP)

  7. ChromAlign: A two-step algorithmic procedure for time alignment of three-dimensional LC-MS chromatographic surfaces.

    Science.gov (United States)

    Sadygov, Rovshan G; Maroto, Fernando Martin; Hühmer, Andreas F R

    2006-12-15

    We present an algorithmic approach to align three-dimensional chromatographic surfaces of LC-MS data of complex mixture samples. The approach consists of two steps. In the first step, we prealign chromatographic profiles: two-dimensional projections of chromatographic surfaces. This is accomplished by correlation analysis using fast Fourier transforms. In this step, a temporal offset that maximizes the overlap and dot product between two chromatographic profiles is determined. In the second step, the algorithm generates correlation matrix elements between full mass scans of the reference and sample chromatographic surfaces. The temporal offset from the first step indicates a range of the mass scans that are possibly correlated, then the correlation matrix is calculated only for these mass scans. The correlation matrix carries information on highly correlated scans, but it does not itself determine the scan or time alignment. Alignment is determined as a path in the correlation matrix that maximizes the sum of the correlation matrix elements. The computational complexity of the optimal path generation problem is reduced by the use of dynamic programming. The program produces time-aligned surfaces. The use of the temporal offset from the first step in the second step reduces the computation time for generating the correlation matrix and speeds up the process. The algorithm has been implemented in a program, ChromAlign, developed in C++ language for the .NET2 environment in WINDOWS XP. In this work, we demonstrate the applications of ChromAlign to alignment of LC-MS surfaces of several datasets: a mixture of known proteins, samples from digests of surface proteins of T-cells, and samples prepared from digests of cerebrospinal fluid. ChromAlign accurately aligns the LC-MS surfaces we studied. In these examples, we discuss various aspects of the alignment by ChromAlign, such as constant time axis shifts and warping of chromatographic surfaces.

  8. Determination of SO2 in the atmosphere using radioactive iodine kryptonate as impregnation medium of chromatographic paper

    International Nuclear Information System (INIS)

    Pruzinec, J.

    1975-01-01

    Chromatographic paper was impregnated with radioiodine kryptonate using the macrodiffusion technique. The decrease with time of the activity of the kryptonate-impregnated paper exposed to SO 2 -contaminated air was measured. From the decrease in chromatographic paper activity, the concentration of SO 2 was determined in the range 300 to 700 ppm. (A.K.)

  9. Underway meteorological, navigational, physical and time series data collected aboard NOAA Ship Hi'ialakai in the North Pacific Ocean and South Pacific Ocean from 2015-01-22 to 2015-05-04 (NCEI Accession 0127322)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NCEI Accession 0127322 contains raw underway meteorological, navigational, physical and time series data logged by the Scientific Computer System (SCS) aboard NOAA...

  10. Underway meteorological, navigational, physical and time series data collected aboard NOAA Ship Nancy Foster in the Gulf of Mexico and North Atlantic Ocean from 2014-09-01 to 2014-09-14 (NODC Accession 0123337)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NODC Accession 0123337 contains raw underway meteorological, navigational, physical and time series data logged by the Scientific Computer System (SCS) aboard NOAA...

  11. Underway meteorological, navigational, physical and time series data collected aboard NOAA Ship Ronald H. Brown in the Arctic Ocean, Beaufort Sea and others from 2015-08-06 to 2015-09-04 (NCEI Accession 0141104)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NODC Accession 0141104 contains raw underway meteorological, navigational, physical and time series data logged by the Scientific Computer System (SCS) aboard NOAA...

  12. Underway meteorological, navigational, physical and time series data collected aboard NOAA Ship Okeanos Explorer in the Gulf of Mexico and North Atlantic Ocean from 2014-05-07 to 2014-05-22 (NODC Accession 0125618)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NODC Accession 0125618 contains raw underway meteorological, navigational, physical and time series data logged by the Scientific Computer System (SCS) aboard NOAA...

  13. Fundulus heteroclitus gonadotropins.5: Small scale chromatographic fractionation of pituitary extracts into components with different steroidogenic activities using homologous bioassays

    Directory of Open Access Journals (Sweden)

    Petrino Teresa R

    2004-03-01

    Full Text Available Abstract Fractionation and characterization of gonadotropins (GtH from Fundulus heteroclitus pituitary extracts were carried out using a biocompatible liquid chromatographic procedure (Pharmacia FPLC system. Chromatographic fractions were monitored for gonadotropic activities (induction of oocyte maturation and steroid production using homologous follicle bioassays in vitro. Size-exclusion chromatography eluted gonadotropic activity in one major protein peak (Mr ~ 30,000. Anion-exchange and hydrophobic-interaction chromatography (HIC yielded two distinct peaks of 17beta-estradiol (E2- and 17alpha-hydroxy,20beta-dihydroprogesterone (DHP-promoting activity with associated oocyte maturation. Two-dimensional chromatography (chromatofocusing followed by HIC resolved pituitary extracts into two active fractions; both induced E2 synthesis, but one was relatively poor in eliciting DHP and testosterone production. Thus, using homologous bioassays, at least two quantitatively different gonadotropic (steroidogenic activities: an E2-promoting gonadotropin (GtH I-like and a DHP-promoting gonadotropin (GtH II-like, which has a lower isoelectric point but greater hydrophobicity than the former, can be distinguished from F. heteroclitus pituitaries by a variety of chromatographic procedures. This study complements previous biochemical and molecular data in F. heteroclitus and substantiates the duality of GtH function in a multiple-spawning teleost.

  14. Underway meteorological, navigational, optical, physical, profile and time series data collected aboard NOAA Ship Pisces in the Gulf of Mexico and North Atlantic Ocean from 2015-05-12 to 2015-06-10 (NCEI Accession 0129440)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NODC Accession 0129440 contains raw underway meteorological, navigational, optical, physical, profile and time series data logged by the Scientific Computer System...

  15. Underway meteorological, navigational, optical, physical, profile and time series data collected aboard NOAA Ship Pisces in the Gulf of Mexico and North Atlantic Ocean from 2017-04-11 to 2017-06-17 (NCEI Accession 0164341)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NCEI Accession 0164341 contains raw underway meteorological, navigational, optical, physical, profile and time series data logged by the Scientific Computer System...

  16. Underway meteorological, navigational, optical, physical and time series data collected aboard NOAA Ship Gordon Gunter in the Gulf of Mexico and North Atlantic Ocean from 2016-04-10 to 2016-04-20 (NCEI Accession 0165360)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NCEI Accession 0165360 contains raw underway meteorological, navigational, optical, physical and time series data logged by the Scientific Computer System (SCS)...

  17. Underway meteorological, navigational, optical, physical and time series data collected aboard NOAA Ship Oscar Elton Sette in the North Pacific Ocean and Philippine Sea from 2014-06-19 to 2014-07-19 (NODC Accession 0123094)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NODC Accession 0123094 contains raw underway meteorological, navigational, optical, physical and time series data logged by the Scientific Computer System (SCS)...

  18. Underway meteorological, navigational, optical, physical and time series data collected aboard NOAA Ship Oscar Dyson in the Gulf of Alaska and North Pacific Ocean from 2017-02-07 to 2017-02-16 (NCEI Accession 0164963)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NCEI Accession 0164963 contains raw underway meteorological, navigational, optical, physical and time series data logged by the Scientific Computer System (SCS)...

  19. Underway meteorological, navigational, optical, physical and time series data collected aboard NOAA Ship Oscar Dyson in the Gulf of Alaska and North Pacific Ocean from 2015-02-09 to 2015-03-03 (NODC Accession 0127242)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NODC Accession 0127242 contains raw underway meteorological, navigational, optical, physical and time series data logged by the Scientific Computer System (SCS)...

  20. Underway meteorological, navigational, physical, profile and time series data collected aboard NOAA Ship Ronald H. Brown in the Arctic Ocean and North Pacific Ocean from 2015-01-14 to 2015-02-13 (NODC Accession 0126056)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NODC Accession 0126056 contains raw underway meteorological, navigational, physical, profile and time series data logged by the Scientific Computer System (SCS)...

  1. Underway meteorological, navigational, optical, physical and time series data collected aboard NOAA Ship Oscar Dyson in the Gulf of Alaska and North Pacific Ocean from 2014-02-21 to 2014-03-01 (NODC Accession 0125086)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NODC Accession 0125086 contains raw underway meteorological, navigational, optical, physical and time series data logged by the Scientific Computer System (SCS)...

  2. Underway meteorological, navigational, optical, physical and time series data collected aboard NOAA Ship Gordon Gunter in the Gulf of Mexico and North Atlantic Ocean from 2015-04-14 to 2015-06-13 (NCEI Accession 0128347)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NCEI Accession 0128347 contains raw underway meteorological, navigational, optical, physical and time series data logged by the Scientific Computer System (SCS)...

  3. Underway meteorological, time series, navigational, physical and optical data collected aboard NOAA Ship Okeanos Explorer in the Gulf of Mexico and North Atlantic Ocean from 2014-02-24 to 2014-03-18 (NCEI Accession 0123616)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NODC Accession 0123616 contains raw underway meteorological, time series, navigational, physical and optical data logged by the Scientific Computer System (SCS)...

  4. Underway meteorological, navigational, optical, physical and time series data collected aboard NOAA Ship Nancy Foster in the Gulf of Mexico and North Atlantic Ocean from 2015-06-15 to 2015-06-28 (NCEI Accession 0129875)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NODC Accession 0129875 contains raw underway meteorological, navigational, optical, physical and time series data logged by the Scientific Computer System (SCS)...

  5. Underway meteorological, navigational, optical, physical and time series data collected aboard NOAA Ship Oscar Dyson in the Gulf of Alaska and North Pacific Ocean from 2013-02-08 to 2013-03-05 (NODC Accession 0124184)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NODC Accession 0124184 contains raw underway meteorological, navigational, optical, physical and time series data logged by the Scientific Computer System (SCS)...

  6. Underway meteorological, navigational, optical, physical and time series data collected aboard NOAA Ship Oscar Dyson in the Gulf of Alaska and North Pacific Ocean from 2016-02-11 to 2016-02-20 (NCEI Accession 0150731)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NCEI Accession 0150731 contains raw underway meteorological, navigational, optical, physical and time series data logged by the Scientific Computer System (SCS)...

  7. Underway meteorological, navigational, optical, physical and time series data collected aboard NOAA Ship Oscar Elton Sette in the North Pacific Ocean and Philippine Sea from 2014-07-24 to 2014-08-25 (NODC Accession 0123095)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NODC Accession 0123095 contains raw underway meteorological, navigational, optical, physical and time series data logged by the Scientific Computer System (SCS)...

  8. Underway meteorological, navigational, optical, physical and time series data collected aboard NOAA Ship Oscar Elton Sette in the North Pacific Ocean and Philippine Sea from 2014-05-31 to 2014-06-16 (NODC Accession 0123093)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NODC Accession 0123093 contains raw underway meteorological, navigational, optical, physical and time series data logged by the Scientific Computer System (SCS)...

  9. Underway meteorological, navigational, optical, physical and time series data collected aboard NOAA Ship Nancy Foster in the Gulf of Mexico and North Atlantic Ocean from 2013-09-10 to 2013-09-20 (NODC Accession 0113488)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NODC Accession 0113488 contains raw underway meteorological, navigational, optical, physical and time series data logged by the Scientific Computer System (SCS)...

  10. High-pressure liquid chromatographic analysis of pramoxine hydrochloride in high lipoid aerosol foam dosage form.

    Science.gov (United States)

    Weinberger, R; Mann, B; Posluszny, J

    1980-04-01

    A rapid and quantitative method for the determination of pramoxine hydrochloride by high-pressure liquid chromatography is presented. The drug is extracted as the salt from a preparation with a high lipoid composition by partitioning it to the aqueous phase of an ether-methanol-water-acetic acid system. The extract is chromatographed on an octadecylsilane bonded packing with a methanol-water-acetic acid-methanesulfonic acid mobile phase. The time required for each separation is approximately 6 min. Analytical recoveries of 100.4 +/- 1.5% were obtained.

  11. Underway meteorological, navigational, physical and time series data collected aboard NOAA Ship Fairweather in the Coastal Waters of SE Alaska and North Pacific Ocean from 2015-09-18 to 2015-11-13 (NCEI Accession 0137857)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NODC Accession 0137857 contains raw underway meteorological, navigational, physical and time series data logged by the Scientific Computer System (SCS) aboard NOAA...

  12. Underway meteorological, navigational, physical and time series data collected aboard NOAA Ship Oscar Dyson in the Coastal Waters of Southeast Alaska and British Columbia from 2016-10-18 to 2016-10-19 (NCEI Accession 0165092)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NCEI Accession 0165092 contains raw underway meteorological, navigational, physical and time series data logged by the Scientific Computer System (SCS) aboard NOAA...

  13. Underway meteorological, navigational, physical and time series data collected aboard NOAA Ship Ronald H. Brown in the North Pacific Ocean and South Pacific Ocean from 2014-08-25 to 2014-09-27 (NODC Accession 0122504)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NODC Accession 0122504 contains raw underway meteorological, navigational, physical and time series data logged by the Scientific Computer System (SCS) aboard NOAA...

  14. Underway meteorological, navigational, physical and time series data collected aboard NOAA Ship Ronald H. Brown in the North Pacific Ocean and South Pacific Ocean from 2014-03-23 to 2014-04-08 (NODC Accession 0120490)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NODC Accession 0120490 contains raw underway meteorological, navigational, physical and time series data logged by the Scientific Computer System (SCS) aboard NOAA...

  15. Artificial neural network model for photosynthetic pigments identification using multi wavelength chromatographic data

    Science.gov (United States)

    Prilianti, K. R.; Hariyanto, S.; Natali, F. D. D.; Indriatmoko, Adhiwibawa, M. A. S.; Limantara, L.; Brotosudarmo, T. H. P.

    2016-04-01

    The development of rapid and automatic pigment characterization method become an important issue due to the fact that there are only less than 1% of plant pigments in the earth have been explored. In this research, a mathematical model based on artificial intelligence approach was developed to simplify and accelerate pigment characterization process from HPLC (high-performance liquid chromatography) procedure. HPLC is a widely used technique to separate and identify pigments in a mixture. Input of the model is chromatographic data from HPLC device and output of the model is a list of pigments which is the spectrum pattern is discovered in it. This model provides two dimensional (retention time and wavelength) fingerprints for pigment characterization which is proven to be more accurate than one dimensional fingerprint (fixed wavelength). Moreover, by mimicking interconnection of the neuron in the nervous systems of the human brain, the model have learning ability that could be replacing expert judgement on evaluating spectrum pattern. In the preprocessing step, principal component analysis (PCA) was used to reduce the huge dimension of the chromatographic data. The aim of this step is to simplify the model and accelerate the identification process. Six photosynthetic pigments i.e. zeaxantin, pheophytin a, α-carotene, β-carotene, lycopene and lutein could be well identified by the model with accuracy up to 85.33% and processing time less than 1 second.

  16. Optical Remote Sensing Algorithm Validation using High-Frequency Underway Biogeochemical Measurements in Three Large Global River Systems

    Science.gov (United States)

    Kuhn, C.; Richey, J. E.; Striegl, R. G.; Ward, N.; Sawakuchi, H. O.; Crawford, J.; Loken, L. C.; Stadler, P.; Dornblaser, M.; Butman, D. E.

    2017-12-01

    More than 93% of the world's river-water volume occurs in basins impacted by large dams and about 43% of river water discharge is impacted by flow regulation. Human land use also alters nutrient and carbon cycling and the emission of carbon dioxide from inland reservoirs. Increased water residence times and warmer temperatures in reservoirs fundamentally alter the physical settings for biogeochemical processing in large rivers, yet river biogeochemistry for many large systems remains undersampled. Satellite remote sensing holds promise as a methodology for responsive regional and global water resources management. Decades of ocean optics research has laid the foundation for the use of remote sensing reflectance in optical wavelengths (400 - 700 nm) to produce satellite-derived, near-surface estimates of phytoplankton chlorophyll concentration. Significant improvements between successive generations of ocean color sensors have enabled the scientific community to document changes in global ocean productivity (NPP) and estimate ocean biomass with increasing accuracy. Despite large advances in ocean optics, application of optical methods to inland waters has been limited to date due to their optical complexity and small spatial scale. To test this frontier, we present a study evaluating the accuracy and suitability of empirical inversion approaches for estimating chlorophyll-a, turbidity and temperature for the Amazon, Columbia and Mississippi rivers using satellite remote sensing. We demonstrate how riverine biogeochemical measurements collected at high frequencies from underway vessels can be used as in situ matchups to evaluate remotely-sensed, near-surface temperature, turbidity, chlorophyll-a derived from the Landsat 8 (NASA) and Sentinel 2 (ESA) satellites. We investigate the use of remote sensing water reflectance to infer trophic status as well as tributary influences on the optical characteristics of the Amazon, Mississippi and Columbia rivers.

  17. Chromatographic study of nucleosides and nucleotides of central nervous system. Identification and first results on changes after total gamma irradiation of brain

    International Nuclear Information System (INIS)

    Valle, C.; Marquer, C.; Pasquier, C.

    Changes of brain energetic state and of different levels after irradiation are studied. The results will be compared with the variations of brain electric activity due to irradiation. Using an ion exchange chromatographic method for separation and quantitative analysis of nucleotides, evaluation of adenylic nucleotides in brain rat have been chosen [fr

  18. Underway meteorological, navigational, physical, profile and time series data collected aboard NOAA Ship Henry B. Bigelow in the Bay of Fundy and North Atlantic Ocean from 2013-09-06 to 2013-11-19 (NCEI Accession 0115901)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NODC Accession 0115901 contains raw underway meteorological, navigational, physical, profile and time series data logged by the Scientific Computer System (SCS)...

  19. Underway meteorological, navigational, physical, profile and time series data collected aboard NOAA Ship Ronald H. Brown in the North Pacific Ocean and South Pacific Ocean from 2014-11-05 to 2014-11-24 (NODC Accession 0123338)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NODC Accession 0123338 contains raw underway meteorological, navigational, physical, profile and time series data logged by the Scientific Computer System (SCS)...

  20. Underway meteorological, navigational, optical, physical, profile and time series data collected aboard NOAA Ship Oregon II in the Gulf of Mexico and North Atlantic Ocean from 2015-07-25 to 2015-09-27 (NCEI Accession 0132051)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NODC Accession 0132051 contains raw underway meteorological, navigational, optical, physical, profile and time series data logged by the Scientific Computer System...

  1. Underway meteorological, navigational, optical, physical, profile and time series data collected aboard NOAA Ship Oregon II in the Gulf of Mexico and North Atlantic Ocean from 2014-05-04 to 2014-05-31 (NODC Accession 0118842)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NODC Accession 0118842 contains raw underway meteorological, navigational, optical, physical, profile and time series data logged by the Scientific Computer System...

  2. Underway meteorological, navigational, optical, physical, profile and time series data collected aboard NOAA Ship Oregon II in the Gulf of Mexico and North Atlantic Ocean from 2017-07-26 to 2017-08-10 (NCEI Accession 0164961)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NCEI Accession 0164961 contains raw underway meteorological, navigational, optical, physical, profile and time series data logged by the Scientific Computer System...

  3. Underway meteorological, navigational, optical, physical, profile and time series data collected aboard NOAA Ship Gordon Gunter in the Gulf of Mexico and North Atlantic Ocean from 2017-07-02 to 2017-07-18 (NCEI Accession 0165352)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NCEI Accession 0165352 contains raw underway meteorological, navigational, optical, physical, profile and time series data logged by the Scientific Computer System...

  4. Underway meteorological, navigational, optical, physical, profile and time series data collected aboard NOAA Ship Oscar Elton Sette in the North Pacific Ocean and Philippine Sea from 2015-06-11 to 2015-07-14 (NCEI Accession 0129902)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NODC Accession 0129902 contains raw underway meteorological, navigational, optical, physical, profile and time series data logged by the Scientific Computer System...

  5. Underway meteorological, navigational, optical, physical, profile and time series data collected aboard NOAA Ship Oregon II in the Gulf of Mexico and North Atlantic Ocean from 2014-07-26 to 2014-09-29 (NODC Accession 0122397)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NODC Accession 0122397 contains raw underway meteorological, navigational, optical, physical, profile and time series data logged by the Scientific Computer System...

  6. Underway meteorological, navigational, optical, physical and time series data collected aboard NOAA Ship Oscar Dyson in the Coastal Waters of Southeast Alaska and British Columbia from 2016-01-25 to 2016-01-27 (NCEI Accession 0164857)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NCEI Accession 0164857 contains raw underway meteorological, navigational, optical, physical and time series data logged by the Scientific Computer System (SCS)...

  7. Underway meteorological, navigational, physical, profile and time series data collected aboard NOAA Ship Ronald H. Brown in the North Pacific Ocean and South Pacific Ocean from 2015-02-27 to 2015-03-30 (NODC Accession 0127092)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NODC Accession 0127092 contains raw underway meteorological, navigational, physical, profile and time series data logged by the Scientific Computer System (SCS)...

  8. Underway meteorological, navigational, optical, physical, profile and time series data collected aboard NOAA Ship Gordon Gunter in the Gulf of Mexico and North Atlantic Ocean from 2014-07-04 to 2014-07-31 (NODC Accession 0120740)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NODC Accession 0120740 contains raw underway meteorological, navigational, optical, physical, profile and time series data logged by the Scientific Computer System...

  9. Underway meteorological, navigational, optical, physical and time series data collected aboard NOAA Ship Oscar Elton Sette in the North Pacific Ocean and South Pacific Ocean from 2016-02-21 to 2016-03-25 (NCEI Accession 0155172)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NCEI Accession 0155172 contains raw underway meteorological, navigational, optical, physical and time series data logged by the Scientific Computer System (SCS)...

  10. Underway meteorological, navigational, optical, physical, profile and time series data collected aboard NOAA Ship Gordon Gunter in the Gulf of Mexico and North Atlantic Ocean from 2015-08-07 to 2015-09-28 (NCEI Accession 0131988)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NODC Accession 0131988 contains raw underway meteorological, navigational, optical, physical, profile and time series data logged by the Scientific Computer System...

  11. Detection of irradiated fruits and vegetables by gas-chromatographic methods and electron spin-resonance

    Energy Technology Data Exchange (ETDEWEB)

    Farag, S.E.A. (National Centre for Radiation Research and Technology, Cairo (Egypt))

    1993-01-01

    Gas chromatographic methods detected some hydrocarbons esp. 17:1, 16:2, 15:0 and 14:1 in irradiated, Avocado, Papaya, Mangoes with 0.75, 1.5, 3.0 kGy and Apricot with 0.5 and 3.0 kGy. The detection of hydrocarbons was clearly at high doses but the low doses need more sensitive conditions using Liquid-Liquid-Gas chromatographic method as used here. Using Electron Spin-Resonance, produce a specific signal from irradiated onion (dried leaves) as well as apricot (hard coat of kernels) after some weeks of irradiation process but not clear with the other foodstuffs. (orig.)

  12. Liquid chromatographic and spectrophotometric methods for the determination of erythromycin stearate and trimethoprim in tablets

    OpenAIRE

    Hassib, Sonia T.; Farag, Awatef E.; Elkady, Ehab F.

    2011-01-01

    Simple, accurate and precise reversed-phase liquid chromatographic (LC) and spectrophotometric methods have been developed and validated for the determination of erythromycin stearate (ERS) and trimethoprim (TMP) in mixture. In LC method, chromatographic separation was achieved on a Symmetry® Waters C18 column (150 × 4.6 mm, 5 μm) based on isocratic elution using a mobile phase consisting of potassium dihydrogen phosphate buffer pH (9):acetonitrile:water (25:100:50, v/v/v) at a flow rate of 1...

  13. A gas/liquid chromatographic-mass spectrometric method for the rapid screening of 250 pesticides in aqueous matrices

    Energy Technology Data Exchange (ETDEWEB)

    Chandramouli, B.; Harvan, D.; Brittain, S.; Hass, R. [Eno River Labs, LLC. Durham, NC (United States)

    2004-09-15

    Pesticide residues in food present a potentially serious and significant cause for concern. Many pesticides have been associated with significant health effects to the nervous and endocrine systems and some have been deemed carcinogenic. There are many well-established techniques for pesticide analysis. However, commercial pesticide methods have traditionally only been available for specific pesticide families, such as chlorinated pesticides or herbicides, and at detection limits ranging from 0.05 ppb to 1 ppm in aqueous matrices. Techniques that can quickly screen for the presence/absence of pesticide residues in food matrices are critical in ensuring the safety of food and water. This paper outlines a combined Gas Chromatographic-High Resolution Mass Spectrometric (GC-HRMS) and Liquid Chromatographic Tandem Mass Spectrometric (LC-MS/MS) screening assay for 250 pesticides that was developed for use in water, and soda samples at screening levels ranging from 0.1-5 ppb. The pesticides selected have been identified by the European Union as being of concern and the target of possible legislation. The list encompasses a variety of pesticide classes and compound groupings.

  14. Gas chromatographic column for the Viking 1975 molecular analysis experiment

    Science.gov (United States)

    Novotny, M.; Hayes, J. M.; Bruner, F.; Simmonds, P. G.

    1975-01-01

    A gas chromatographic column has been developed for use in the remote analysis of the Martian surface. The column, which utilizes a liquid-modified organic adsorbent (Tenax) as the stationary phase, provides efficient transmission and resolution of nanogram quantities of organic materials in the presence of millionfold excesses of water and carbon dioxide.

  15. The co-feature ratio, a novel method for the measurement of chromatographic and signal selectivity in LC-MS-based metabolomics

    International Nuclear Information System (INIS)

    Elmsjö, Albert; Haglöf, Jakob; Engskog, Mikael K.R.; Nestor, Marika; Arvidsson, Torbjörn; Pettersson, Curt

    2017-01-01

    Evaluation of analytical procedures, especially in regards to measuring chromatographic and signal selectivity, is highly challenging in untargeted metabolomics. The aim of this study was to suggest a new straightforward approach for a systematic examination of chromatographic and signal selectivity in LC-MS-based metabolomics. By calculating the ratio between each feature and its co-eluting features (the co-features), a measurement of the chromatographic selectivity (i.e. extent of co-elution) as well as the signal selectivity (e.g. amount of adduct formation) of each feature could be acquired, the co-feature ratio. This approach was used to examine possible differences in chromatographic and signal selectivity present in samples exposed to three different sample preparation procedures. The capability of the co-feature ratio was evaluated both in a classical targeted setting using isotope labelled standards as well as without standards in an untargeted setting. For the targeted analysis, several metabolites showed a skewed quantitative signal due to poor chromatographic selectivity and/or poor signal selectivity. Moreover, evaluation of the untargeted approach through multivariate analysis of the co-feature ratios demonstrated the possibility to screen for metabolites displaying poor chromatographic and/or signal selectivity characteristics. We conclude that the co-feature ratio can be a useful tool in the development and evaluation of analytical procedures in LC-MS-based metabolomics investigations. Increased selectivity through proper choice of analytical procedures may decrease the false positive and false negative discovery rate and thereby increase the validity of any metabolomic investigation. - Highlights: • The co-feature ratio (CFR) is introduced. • CFR measures chromatographic and signal selectivity of a feature. • CFR can be used for evaluating experimental procedures in metabolomics. • CFR can aid in locating features with poor selectivity.

  16. The co-feature ratio, a novel method for the measurement of chromatographic and signal selectivity in LC-MS-based metabolomics

    Energy Technology Data Exchange (ETDEWEB)

    Elmsjö, Albert, E-mail: Albert.Elmsjo@farmkemi.uu.se [Department of Medicinal Chemistry, Division of Analytical Pharmaceutical Chemistry, Uppsala University (Sweden); Haglöf, Jakob; Engskog, Mikael K.R. [Department of Medicinal Chemistry, Division of Analytical Pharmaceutical Chemistry, Uppsala University (Sweden); Nestor, Marika [Department of Immunology, Genetics and Pathology, Uppsala University (Sweden); Arvidsson, Torbjörn [Department of Medicinal Chemistry, Division of Analytical Pharmaceutical Chemistry, Uppsala University (Sweden); Medical Product Agency, Uppsala (Sweden); Pettersson, Curt [Department of Medicinal Chemistry, Division of Analytical Pharmaceutical Chemistry, Uppsala University (Sweden)

    2017-03-01

    Evaluation of analytical procedures, especially in regards to measuring chromatographic and signal selectivity, is highly challenging in untargeted metabolomics. The aim of this study was to suggest a new straightforward approach for a systematic examination of chromatographic and signal selectivity in LC-MS-based metabolomics. By calculating the ratio between each feature and its co-eluting features (the co-features), a measurement of the chromatographic selectivity (i.e. extent of co-elution) as well as the signal selectivity (e.g. amount of adduct formation) of each feature could be acquired, the co-feature ratio. This approach was used to examine possible differences in chromatographic and signal selectivity present in samples exposed to three different sample preparation procedures. The capability of the co-feature ratio was evaluated both in a classical targeted setting using isotope labelled standards as well as without standards in an untargeted setting. For the targeted analysis, several metabolites showed a skewed quantitative signal due to poor chromatographic selectivity and/or poor signal selectivity. Moreover, evaluation of the untargeted approach through multivariate analysis of the co-feature ratios demonstrated the possibility to screen for metabolites displaying poor chromatographic and/or signal selectivity characteristics. We conclude that the co-feature ratio can be a useful tool in the development and evaluation of analytical procedures in LC-MS-based metabolomics investigations. Increased selectivity through proper choice of analytical procedures may decrease the false positive and false negative discovery rate and thereby increase the validity of any metabolomic investigation. - Highlights: • The co-feature ratio (CFR) is introduced. • CFR measures chromatographic and signal selectivity of a feature. • CFR can be used for evaluating experimental procedures in metabolomics. • CFR can aid in locating features with poor selectivity.

  17. Gas chromatographic determination of calcium propionate added as preservative to bread.

    Science.gov (United States)

    Lamkin, W M; Unruh, N C; Pomeranz, Y

    1987-01-01

    A simple and rapid gas chromatographic procedure was developed for determining low concentrations of propionate added as a preservative to bread. A bread sample to be analyzed was ground in a meat grinder with a 3 mm hole plate and finely divided by rubbing through a No. 8 sieve. The propionate was then extracted into 0.050M formic acid in a blender at low speed for 5 min, and an aliquot of a filtrate was analyzed directly by gas chromatography. Chromatographic separation was accomplished on a Carbopack C column coated with 0.3% (w/w) Carbowax 20M and 0.1% (w/w) phosphoric acid. Less than 0.2 ppm propionic acid could be detected in the aqueous extract. Over the range of 0.03-0.23% calcium propionate, average relative error was -1.20% with an average coefficient of variation of 2.02%.

  18. Spectroscopic and chromatographic analysis of oil from an oil shale flash pyrolysis unit

    Energy Technology Data Exchange (ETDEWEB)

    Khraisha, V.H.; Irqsousi, N.A. [University of Jordan, Amman (Jordan). Dept. of Chemical Engineering; Shabib, I.M. [Applied Science Univ., Amman (Jordan). Dept. of Chemistry

    2003-01-01

    In this investigation, spectroscopic (FT-IR, UV-Vis, {sup 1}H NMR) and chromatographic (GC) techniques were used to analyze two Jordanian shale oils, Sultani and El-Lajjun. The oils were extracted at different pyrolysis temperatures (400-500{sup o}C) using a fluidized bed reactor. The spectroscopic and chromatographic analyses show that the variation of pyrolysis temperature has no significant effect on the composition of the produced oil. The {sup 1}H NMR results indicate that the protons of methyl and methelyene represent the bulk of the hydrogen ({approx}90%) in most shale oil samples. GC analysis reveals that the oil samples contain n-alkanes with a predominant proportion of n-C{sub 25}. (Author)

  19. Underway meteorological, navigational, physical and time series data collected aboard NOAA Ship Hi'ialakai in the North Pacific Ocean, Philippine Sea and South Pacific Ocean from 2017-03-26 to 2017-06-21 (NCEI Accession 0164429)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NCEI Accession 0164429 contains raw underway meteorological, navigational, physical and time series data logged by the Scientific Computer System (SCS) aboard NOAA...

  20. NBS measurement system for natural argon-37

    International Nuclear Information System (INIS)

    Currie, L.A.; Lindstrom, R.M.

    1973-01-01

    A project to determine the cosmic-ray production rate and the natural levels of 35-day half-life 37 Ar in the atmosphere has been underway at the National Bureau of Standards for about the past year. The prime objective of this project is to determine the spatial dependence of 37 Ar production in the atmosphere, and the spatial distribution of the naturally-produced 37 Ar (observed concentrations). The results of this study are to be used, in cooperation with L. Machta (National Oceanographic and Atmospheric Administration), to derive information about atmospheric mixing. The purpose of this communication, however, is to present a general description of the various components of the measurement system. As the lowest concentrations of interest are but approximately equal to 10 -3 dpm ( 37 Ar)/l-Ar, very high sensitivity measurement techniques are required. Among the techniques which we have adopted are: quantitative separation of the noble gases from about 1 m 3 of air, using a CaC 2 reactor; gas chromatographic separation of the argon fraction; isotopic enrichment (by a factor of approximately equal to 100) of purified argon; use of specially selected low-level gas proportional counters together with massive shielding and anticoincidence meson cancellation; and the application of pulse discrimination based upon both amplitude (energy) and pulse shape. Finally, on-line computer techniques are being applied for data acquisition and system control

  1. Recent advances in metal-organic frameworks and covalent organic frameworks for sample preparation and chromatographic analysis.

    Science.gov (United States)

    Wang, Xuan; Ye, Nengsheng

    2017-12-01

    In the field of analytical chemistry, sample preparation and chromatographic separation are two core procedures. The means by which to improve the sensitivity, selectivity and detection limit of a method have become a topic of great interest. Recently, porous organic frameworks, such as metal-organic frameworks (MOFs) and covalent organic frameworks (COFs), have been widely used in this research area because of their special features, and different methods have been developed. This review summarizes the applications of MOFs and COFs in sample preparation and chromatographic stationary phases. The MOF- or COF-based solid-phase extraction (SPE), solid-phase microextraction (SPME), gas chromatography (GC), high-performance liquid chromatography (HPLC) and capillary electrochromatography (CEC) methods are described. The excellent properties of MOFs and COFs have resulted in intense interest in exploring their performance and mechanisms for sample preparation and chromatographic separation. © 2017 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  2. Ion Chromatographic Analyses of Sea Waters, Brines and Related Samples

    Directory of Open Access Journals (Sweden)

    Nataša Gros

    2013-06-01

    Full Text Available This review focuses on the ion chromatographic methods for the analyses of natural waters with high ionic strength. At the beginning a natural diversity in ionic composition of waters is highlighted and terminology clarified. In continuation a brief overview of other review articles of potential interest is given. A review of ion chromatographic methods is organized in four sections. The first section comprises articles focused on the determination of ionic composition of water samples as completely as possible. The sections—Selected Anions, Selected Cations and Metals—follow. The most essential experimental conditions used in different methods are summarized in tables for a rapid comparison. Techniques encountered in the reviewed articles comprise: direct determinations of ions in untreated samples with ion- or ion-exclusion chromatography, or electrostatic ion chromatography; matrix elimination with column-switching; pre-concentration with a chelation ion chromatography and purge-and-trap pre-concentration. Different detection methods were used: non-suppressed conductometric or suppressed conductometric, direct spectrometric or spectrometric after a post-column derivetization, and inductively coupled plasma in combination with optical emission or mass spectrometry.

  3. Underway meteorological, navigational, optical, physical and time series data collected aboard NOAA Ship Oscar Dyson in the Bering Sea, Gulf of Alaska and North Pacific Ocean from 2014-04-04 to 2014-05-02 (NODC Accession 0125006)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NODC Accession 0125006 contains raw underway meteorological, navigational, optical, physical and time series data logged by the Scientific Computer System (SCS)...

  4. Underway meteorological, navigational, optical, physical, profile and time series data collected aboard NOAA Ship Pisces in the Caribbean Sea, Gulf of Mexico and North Atlantic Ocean from 2015-10-12 to 2015-11-24 (NCEI Accession 0138341)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NCEI Accession 0138341 contains raw underway meteorological, navigational, optical, physical, profile and time series data logged by the Scientific Computer System...

  5. Underway meteorological, navigational, optical, physical and time series data collected aboard NOAA Ship Oscar Dyson in the Bering Sea, Gulf of Alaska and North Pacific Ocean from 2013-05-15 to 2013-06-01 (NODC Accession 0124207)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NODC Accession 0124207 contains raw underway meteorological, navigational, optical, physical and time series data logged by the Scientific Computer System (SCS)...

  6. Underway meteorological, navigational, optical, physical and time series data collected aboard NOAA Ship Oscar Dyson in the Bering Sea, Gulf of Alaska and North Pacific Ocean from 2013-04-29 to 2013-05-11 (NODC Accession 0124208)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NODC Accession 0124208 contains raw underway meteorological, navigational, optical, physical and time series data logged by the Scientific Computer System (SCS)...

  7. Underway meteorological, navigational, optical, physical and time series data collected aboard NOAA Ship Oscar Dyson in the Bering Sea, Gulf of Alaska and North Pacific Ocean from 2017-05-11 to 2017-06-02 (NCEI Accession 0165021)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NCEI Accession 0165021 contains raw underway meteorological, navigational, optical, physical and time series data logged by the Scientific Computer System (SCS)...

  8. Underway meteorological, navigational, optical, physical and time series data collected aboard NOAA Ship Oscar Dyson in the Bering Sea, Gulf of Alaska and North Pacific Ocean from 2015-08-20 to 2015-09-02 (NCEI Accession 0131578)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NODC Accession 0131578 contains raw underway meteorological, navigational, optical, physical and time series data logged by the Scientific Computer System (SCS)...

  9. Underway meteorological, navigational, optical, physical and time series data collected aboard NOAA Ship Oscar Dyson in the Bering Sea, Gulf of Alaska and North Pacific Ocean from 2017-06-08 to 2017-07-15 (NCEI Accession 0165028)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NCEI Accession 0165028 contains raw underway meteorological, navigational, optical, physical and time series data logged by the Scientific Computer System (SCS)...

  10. Underway meteorological, navigational, optical, physical and time series data collected aboard NOAA Ship Oscar Dyson in the Bering Sea, Gulf of Alaska and North Pacific Ocean from 2015-09-23 to 2015-10-06 (NCEI Accession 0137392)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NODC Accession 0137392 contains raw underway meteorological, navigational, optical, physical and time series data logged by the Scientific Computer System (SCS)...

  11. Underway meteorological, navigational, optical, physical and time series data collected aboard NOAA Ship Oscar Dyson in the Bering Sea, Gulf of Alaska and North Pacific Ocean from 2016-09-30 to 2016-10-07 (NCEI Accession 0165090)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NCEI Accession 0165090 contains raw underway meteorological, navigational, optical, physical and time series data logged by the Scientific Computer System (SCS)...

  12. Underway meteorological, navigational, optical, physical and time series data collected aboard NOAA Ship Oscar Dyson in the Bering Sea, Gulf of Alaska and North Pacific Ocean from 2016-03-09 to 2016-03-24 (NCEI Accession 0150822)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NCEI Accession 0150822 contains raw underway meteorological, navigational, optical, physical and time series data logged by the Scientific Computer System (SCS)...

  13. Underway meteorological, navigational, optical, physical and time series data collected aboard NOAA Ship Oscar Dyson in the Bering Sea, Gulf of Alaska and North Pacific Ocean from 2013-06-08 to 2013-08-09 (NODC Accession 0123940)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NODC Accession 0123940 contains raw underway meteorological, navigational, optical, physical and time series data logged by the Scientific Computer System (SCS)...

  14. Underway meteorological, navigational, optical, physical and time series data collected aboard NOAA Ship Oscar Dyson in the Bering Sea, Gulf of Alaska and North Pacific Ocean from 2016-03-02 to 2016-03-09 (NCEI Accession 0150732)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NCEI Accession 0150732 contains raw underway meteorological, navigational, optical, physical and time series data logged by the Scientific Computer System (SCS)...

  15. Underway meteorological, navigational, optical, physical and time series data collected aboard NOAA Ship Oscar Dyson in the Bering Sea, Gulf of Alaska and North Pacific Ocean from 2015-05-14 to 2015-06-05 (NCEI Accession 0130586)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NODC Accession 0130586 contains raw underway meteorological, navigational, optical, physical and time series data logged by the Scientific Computer System (SCS)...

  16. Underway meteorological, navigational, optical, physical and time series data collected aboard NOAA Ship Oscar Dyson in the Bering Sea, Gulf of Alaska and North Pacific Ocean from 2014-03-13 to 2014-03-25 (NODC Accession 0124597)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NODC Accession 0124597 contains raw underway meteorological, navigational, optical, physical and time series data logged by the Scientific Computer System (SCS)...

  17. Underway meteorological, navigational, optical, physical and time series data collected aboard NOAA Ship Oscar Dyson in the Bering Sea, Gulf of Alaska and North Pacific Ocean from 2013-08-15 to 2013-09-19 (NODC Accession 0123941)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NODC Accession 0123941 contains raw underway meteorological, navigational, optical, physical and time series data logged by the Scientific Computer System (SCS)...

  18. Underway meteorological, navigational, optical, physical and time series data collected aboard NOAA Ship Oscar Dyson in the Bering Sea, Gulf of Alaska and North Pacific Ocean from 2014-08-17 to 2014-10-06 (NODC Accession 0124596)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NODC Accession 0124596 contains raw underway meteorological, navigational, optical, physical and time series data logged by the Scientific Computer System (SCS)...

  19. Underway meteorological, navigational, optical, physical and time series data collected aboard NOAA Ship Oscar Dyson in the Bering Sea, Gulf of Alaska and North Pacific Ocean from 2015-04-24 to 2015-05-10 (NCEI Accession 0130737)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NODC Accession 0130737 contains raw underway meteorological, navigational, optical, physical and time series data logged by the Scientific Computer System (SCS)...

  20. Underway meteorological, navigational, optical, physical and time series data collected aboard NOAA Ship Oscar Dyson in the Bering Sea, Gulf of Alaska and North Pacific Ocean from 2017-04-22 to 2017-05-08 (NCEI Accession 0165013)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NCEI Accession 0165013 contains raw underway meteorological, navigational, optical, physical and time series data logged by the Scientific Computer System (SCS)...

  1. Incorporating high-pressure electroosmotic pump and a nano-flow gradient generator into a miniaturized liquid chromatographic system for peptide analysis.

    Science.gov (United States)

    Chen, Apeng; Lynch, Kyle B; Wang, Xiaochun; Lu, Joann J; Gu, Congying; Liu, Shaorong

    2014-09-24

    We integrate a high-pressure electroosmotic pump (EOP), a nanoflow gradient generator, and a capillary column into a miniaturized liquid chromatographic system that can be directly coupled with a mass spectrometer for proteomic analysis. We have recently developed a low-cost high-pressure EOP capable of generating pressure of tens of thousands psi, ideal for uses in miniaturized HPLC. The pump worked smoothly when it was used for isocratic elutions. When it was used for gradient elutions, generating reproducible gradient profiles was challenging; because the pump rate fluctuated when the pump was used to pump high-content organic solvents. This presents an issue for separating proteins/peptides since high-content organic solvents are often utilized. In this work, we solve this problem by incorporating our high-pressure EOP with a nano-flow gradient generator so that the EOP needs only to pump an aqueous solution. With this combination, we develop a capillary-based nano-HPLC system capable of performing nano-flow gradient elution; the pump rate is stable, and the gradient profiles are reproducible and can be conveniently tuned. To demonstrate its utility, we couple it with either a UV absorbance detector or a mass spectrometer for peptide separations. Copyright © 2014. Published by Elsevier B.V.

  2. Gas chromatographic determination of impurities of inorganic compounds

    International Nuclear Information System (INIS)

    Drugov, Yu.S.

    1985-01-01

    Methods of concentration, separation, detection in gas chromatographic determination of impurities of inorganic compounds including low-boiling gases, reactive gases, organometallic compounds, free metals, anions, etc. are reviewed. Methods of reaction gas chromatography for determining reactive gases, water, anions, metal chelates are considered in detail as well as methods of reaction-sorption concentration and reaction gas extraction. The application of gas chromatograpny ior anaiysis of water and atmosphere contamination, for determination of impurities in highly pure solid substances and gases is described

  3. Underway meteorological, navigational, physical and time series data collected aboard NOAA Ship Ronald H. Brown in the Coastal Waters of SE Alaska and North Pacific Ocean from 2016-06-23 to 2016-07-09 (NCEI Accession 0155758)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NCEI Accession 0155758 contains raw underway meteorological, navigational, physical and time series data logged by the Scientific Computer System (SCS) aboard NOAA...

  4. Underway meteorological, navigational, physical and time series data collected aboard NOAA Ship Ronald H. Brown in the North Atlantic Ocean, Rio de la Plata and others from 2017-02-11 to 2017-03-15 (NCEI Accession 0164157)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NCEI Accession 0164157 contains raw underway meteorological, navigational, physical and time series data logged by the Scientific Computer System (SCS) aboard NOAA...

  5. Chromatographic separation of rhenium in alumina-methanol/sulfuric acid system

    International Nuclear Information System (INIS)

    Oguma, Koichi

    1983-01-01

    The adsorption behavior of a number of metals on alumina was surveyed in a methanol-(0.005 -- 0.5) M H 2 SO 4 (3 : 1 v/v) developing solvent by thin-layer chromatography. Over the acid concentration range tested, Re(VII) does not favor the alumina phase to any great extent while the most other metals are strongly adsorbed on alumina. These findings allowed to establish a column chromatographic technique for selective separation of rhenium in a methanol-0.05 M H 2 SO 4 (3 : 1 v/v) eluent. The separation technique thus established was applied to molybdenite analysis for rhenium. About 100-mg powdered sample containing ca. 100 ppm rhenium was decomposed with HNO 3 and then evaporated nearly to dryness. The residue was dissolved in NH 4 OH and the excess NH 4 OH was expelled by evaporation to dryness. The residue was dissolved in 2.5-ml 0.5 M H 2 SO 4 and 10-ml water, the insoluble materials filtered off, and the filtrate diluted to exactly 25 ml with water. A 10-ml aliquot of this solution was mixed with 30-ml methanol and the mixture was passed through a column (diameter 15 mm, bed height 30 mm) containing 5 g of alumina. The column was then washed with 20 ml of a methanol-0.05 M H 2 SO 4 (3 : 1 v/v) mixture. Rhenium was recovered from the loaded solution and the subsequent washings, and was determined spectrophotometrically with Methylene Blue as a chromogenic reagent. The values obtained from four samples of molybdenite are in good agreement with those obtained by neutron activation analysis. The relative standard deviation (n = 4; calculated from the range) was between 2.0 and 5.2 %. (author)

  6. The Use of TOC Reconciliation as a Means of Establishing the Degree to Which Chromatographic Screening of Plastic Material Extracts for Organic Extractables Is Complete.

    Science.gov (United States)

    Jenke, Dennis; Couch, Thomas R; Robinson, Sarah J; Volz, Trent J; Colton, Raymond H

    2014-01-01

    Extracts of plastic packaging, manufacturing, and delivery systems (or their materials of construction) are analyzed by chromatographic methods to establish the system's extractables profile. The testing strategy consists of multiple orthogonal chromatographic methods, for example, gas and liquid chromatography with multiple detection strategies. Although this orthogonal testing strategy is comprehensive, it is not necessarily complete and members of the extractables profile can elude detection and/or accurate identification/quantification. Because the chromatographic methods rarely indicate that some extractables have been missed, another means of assessing the completeness of the profiling activity must be established. If the extracts are aqueous and contain no organic additives (e.g., pH buffers), then they can be analyzed for their total organic carbon content (TOC). Additionally, the TOC of an extract can be calculated based on the extractables revealed by the screening analyses. The measured and calculated TOC can be reconciled to establish the completeness and accuracy of the extractables profile. If the reconciliation is poor, then the profile is either incomplete or inaccurate and additional testing is needed to establish the complete and accurate profile. Ten test materials and components of systems were extracted and their extracts characterized for organic extractables using typical screening procedures. Measured and calculated TOC was reconciled to establish the completeness of the revealed extractables profile. When the TOC reconciliation was incomplete, the profiling was augmented with additional analytical testing to reveal the missing members of the organic extractables profile. This process is illustrated via two case studies involving aqueous extracts of sterile filters. Plastic materials and systems used to manufacture, contain, store, and deliver pharmaceutical products are extracted and the extracts analyzed to establish the materials' (or

  7. Ion chromatographic determination of Di-n-butyl phosphate in degraded organic solvent

    International Nuclear Information System (INIS)

    Velavendan, P.; Pandey, N.K.; Kamachi Mudali, U.; Natarajan, R.

    2011-01-01

    In the present work a method for the determination of Di-n-butyl phosphate in organic streams using Ion Chromatography technique is developed and described here. The method involves the separation of Di-n-butyl phosphate (DBP) from 30% TBP-NPH (Tri-n-butylphosphate diluted in Normal Paraffin Hydrocarbon) and uranium/nitric acid matrix by an extraction of DBP in alkaline medium and subsequent ion-exchange separation in ion chromatography column followed by suppressed conductivity detection. Direct determination of DBP in lean/loaded organic solvent will lead to in accurate determination of DBP due to organic interference. DBP is quantified to lower limit of 1 ppm with 3% RSD. The results obtained with ion chromatographic technique are compared with those obtained by standard gas chromatographic technique. The developed method is much faster and total analysis can be completed within two hours. (author)

  8. Different Spectrophotometric and Chromatographic Methods for Determination of Mepivacaine and Its Toxic Impurity.

    Science.gov (United States)

    Abdelwahab, Nada S; Fared, Nehal F; Elagawany, Mohamed; Abdelmomen, Esraa H

    2017-09-01

    Stability-indicating spectrophotometric, TLC-densitometric, and ultra-performance LC (UPLC) methods were developed for the determination of mepivacaine HCl (MEP) in the presence of its toxic impurity, 2,6-dimethylanaline (DMA). Different spectrophotometric methods were developed for the determination of MEP and DMA. In a dual-wavelength method combined with direct spectrophotometric measurement, the absorbance difference between 221.4 and 240 nm was used for MEP measurements, whereas the absorbance at 283 nm was used for measuring DMA in the binary mixture. In the second-derivative method, amplitudes at 272.2 and 232.6 nm were recorded and used for the determination of MEP and DMA, respectively. The developed TLC-densitometric method depended on chromatographic separation using silica gel 60 F254 TLC plates as a stationary phase and methanol-water-acetic acid (9 + 1 + 0.1, v/v/v) as a developing system, with UV scanning at 230 nm. The developed UPLC method depended on separation using a C18 column (250 × 4.6 mm id, 5 μm particle size) as a stationary phase and acetonitrile-water (40 + 60, v/v; pH 4 with phosphoric acid) as a mobile phase at a flow rate of 0.4 mL/min, with UV detection at 215 nm. The chromatographic run time was approximately 1 min. The proposed methods were validated with respect to International Conference on Harmonization guidelines regarding precision, accuracy, ruggedness, robustness, and specificity.

  9. Underway meteorological, navigational, optical, physical and time series data collected aboard NOAA Ship Bell M. Shimada in the Coastal Waters of SE Alaska and North Pacific Ocean from 2016-02-21 to 2016-03-11 (NCEI Accession 0150967)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NCEI Accession 0150967 contains raw underway meteorological, navigational, optical, physical and time series data logged by the Scientific Computer System (SCS)...

  10. Underway meteorological, navigational, physical, profile and time series data collected aboard NOAA Ship Ronald H. Brown in the Coral Sea, North Pacific Ocean and South Pacific Ocean from 2014-10-06 to 2014-11-01 (NODC Accession 0123096)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NODC Accession 0123096 contains raw underway meteorological, navigational, physical, profile and time series data logged by the Scientific Computer System (SCS)...

  11. Automated optimization and construction of chemometric models based on highly variable raw chromatographic data.

    Science.gov (United States)

    Sinkov, Nikolai A; Johnston, Brandon M; Sandercock, P Mark L; Harynuk, James J

    2011-07-04

    Direct chemometric interpretation of raw chromatographic data (as opposed to integrated peak tables) has been shown to be advantageous in many circumstances. However, this approach presents two significant challenges: data alignment and feature selection. In order to interpret the data, the time axes must be precisely aligned so that the signal from each analyte is recorded at the same coordinates in the data matrix for each and every analyzed sample. Several alignment approaches exist in the literature and they work well when the samples being aligned are reasonably similar. In cases where the background matrix for a series of samples to be modeled is highly variable, the performance of these approaches suffers. Considering the challenge of feature selection, when the raw data are used each signal at each time is viewed as an individual, independent variable; with the data rates of modern chromatographic systems, this generates hundreds of thousands of candidate variables, or tens of millions of candidate variables if multivariate detectors such as mass spectrometers are utilized. Consequently, an automated approach to identify and select appropriate variables for inclusion in a model is desirable. In this research we present an alignment approach that relies on a series of deuterated alkanes which act as retention anchors for an alignment signal, and couple this with an automated feature selection routine based on our novel cluster resolution metric for the construction of a chemometric model. The model system that we use to demonstrate these approaches is a series of simulated arson debris samples analyzed by passive headspace extraction, GC-MS, and interpreted using partial least squares discriminant analysis (PLS-DA). Copyright © 2011 Elsevier B.V. All rights reserved.

  12. Underway meteorological, navigational, physical and time series data collected aboard NOAA Ship Fairweather in the Coastal Waters of Southeast Alaska and British Columbia and North Pacific Ocean from 2016-05-25 to 2016-06-18 (NCEI Accession 0162234)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NCEI Accession 0162234 contains raw underway meteorological, navigational, physical and time series data logged by the Scientific Computer System (SCS) aboard NOAA...

  13. Underway meteorological, navigational, physical and time series data collected aboard NOAA Ship Ronald H. Brown in the Gulf of Alaska, North Pacific Ocean and South Pacific Ocean from 2015-04-10 to 2015-06-24 (NCEI Accession 0129524)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NODC Accession 0129524 contains raw underway meteorological, navigational, physical and time series data logged by the Scientific Computer System (SCS) aboard NOAA...

  14. Chromatographic separation of Iodine species for environmental studies

    Energy Technology Data Exchange (ETDEWEB)

    Machado, E.C. [Universidade Federal Fluminense, Niteroi, RJ (Brazil). Dept. de Geoquimica]. E-mail: geoedin@vm.uff.br; Bellido, A.V.B. [Universidade Federal Fluminense, Niteroi, RJ (Brazil). Dept. de Fisico-Quimica]. E-mail: alf@risc2.rmn.uff.br; Bellido, L.F. [Comissao Nacional de Energia Nuclear (CNEN), Rio de Janeiro, RJ (Brazil)]. E-mail: lbellido@cnen.gov.br

    1999-07-01

    In this work a experimental method was developed to separate iodine species from environmental samples by using adsorption chromatography. The radionuclide {sup 123} I which has a half-life of 13 h and a convenient gamma ray of 159 keV was used to investigate a fast and efficient procedure for the separation of iodide and iodate ions in seawater from mangrove samples. The radio-iodine tracer technique is very useful, particularly in kinetic studies because it is easy to detect without any interference of concentration due to the small amount of tracer that is spiked. It is also possible to add two tracers (I-123 and I-131) in different oxidation states. Three chromatographic methods were studied: paper, thin layer and adsorption chromatography with silica and alumina. It was found that paper chromatography is very useful for checking the valence adjustment of the radioiodine species. Initially, several coefficient distributions of iodine species by adsorption in silica and alumina from NaOH, NaHCO{sub 3} and NaNO{sub 3} solutions (in the range 05. - 0.0001 m) were determined. The best separation so far was achieved by loading the sample (after adjusting the concentration to 0.1 NNaNO{sub 3}) into a chromatographic column with Al{sub 2} O{sub 3}. The iodide passes through the column and after washing the column, the iodate was removed by eluting with 1.0 M NaHCO{sub 3} solution. (author)

  15. Chromatographic separation of Iodine species for environmental studies

    International Nuclear Information System (INIS)

    Machado, E.C.

    1999-01-01

    In this work a experimental method was developed to separate iodine species from environmental samples by using adsorption chromatography. The radionuclide 123 I which has a half-life of 13 h and a convenient gamma ray of 159 keV was used to investigate a fast and efficient procedure for the separation of iodide and iodate ions in seawater from mangrove samples. The radio-iodine tracer technique is very useful, particularly in kinetic studies because it is easy to detect without any interference of concentration due to the small amount of tracer that is spiked. It is also possible to add two tracers (I-123 and I-131) in different oxidation states. Three chromatographic methods were studied: paper, thin layer and adsorption chromatography with silica and alumina. It was found that paper chromatography is very useful for checking the valence adjustment of the radioiodine species. Initially, several coefficient distributions of iodine species by adsorption in silica and alumina from NaOH, NaHCO 3 and NaNO 3 solutions (in the range 05. - 0.0001 m) were determined. The best separation so far was achieved by loading the sample (after adjusting the concentration to 0.1 NNaNO 3 ) into a chromatographic column with Al 2 O 3 . The iodide passes through the column and after washing the column, the iodate was removed by eluting with 1.0 M NaHCO 3 solution. (author)

  16. The contribution of the hydrogen bond acidity on the lipophilicity of drugs estimated from chromatographic measurements.

    Science.gov (United States)

    Pallicer, Juan M; Pascual, Rosalia; Port, Adriana; Rosés, Martí; Ràfols, Clara; Bosch, Elisabeth

    2013-02-14

    The influence of the hydrogen bond acidity when the 1-octanol/water partition coefficient (log P(o/w)) of drugs is determined from chromatographic measurements was studied in this work. This influence was firstly evaluated by means of the comparison between the Abraham solvation parameter model when it is applied to express the 1-octanol/water partitioning and the chromatographic retention, expressed as the solute polarity p. Then, several hydrogen bond acidity descriptors were compared in order to determine properly the log P(o/w) of drugs. These descriptors were obtained from different software and comprise two-dimensional parameters such as the calculated Abraham hydrogen bond acidity A and three-dimensional descriptors like HDCA-2 from CODESSA program or WO1 and DRDODO descriptors calculated from Volsurf+software. The additional HOMO-LUMO polarizability descriptor should be added when the three-dimensional descriptors are used to complement the chromatographic retention. The models generated using these descriptors were compared studying the correlations between the determined log P(o/w) values and the reference ones. The comparison showed that there was no significant difference between the tested models and any of them was able to determine the log P(o/w) of drugs from a single chromatographic measurement and the correspondent molecular descriptors terms. However, the model that involved the calculated A descriptor was simpler and it is thus recommended for practical uses. Copyright © 2012 Elsevier B.V. All rights reserved.

  17. Advanced hyphenated chromatographic-mass spectrometry in mycotoxin determination: current status and prospects.

    Science.gov (United States)

    Li, Peiwu; Zhang, Zhaowei; Hu, Xiaofeng; Zhang, Qi

    2013-01-01

    Mass spectrometric techniques are essential for advanced research in food safety and environmental monitoring. These fields are important for securing the health of humans and animals, and for ensuring environmental security. Mycotoxins, toxic secondary metabolites of filamentous fungi, are major contaminants of agricultural products, food and feed, biological samples, and the environment as a whole. Mycotoxins can cause cancers, nephritic and hepatic diseases, various hemorrhagic syndromes, and immune and neurological disorders. Mycotoxin-contaminated food and feed can provoke trade conflicts, resulting in massive economic losses. Risk assessment of mycotoxin contamination for humans and animals generally depends on clear identification and reliable quantitation in diversified matrices. Pioneering work on mycotoxin quantitation using mass spectrometry (MS) was performed in the early 1970s. Now, unambiguous confirmation and quantitation of mycotoxins can be readily achieved with a variety hyphenated techniques that combine chromatographic separation with MS, including liquid chromatography (LC) or gas chromatography (GC). With the advent of atmospheric pressure ionization, LC-MS has become a routine technique. Recently, the co-occurrence of multiple mycotoxins in the same sample has drawn an increasing amount of attention. Thus, modern analyses must be able to detect and quantitate multiple mycotoxins in a single run. Improvements in tandem MS techniques have been made to achieve this purpose. This review describes the advanced research that has been done regarding mycotoxin determination using hyphenated chromatographic-MS techniques, but is not a full-circle survey of all the literature published on this topic. The present work provides an overview of the various hyphenated chromatographic-MS-based strategies that have been applied to mycotoxin analysis, with a focus on recent developments. The use of chromatographic-MS to measure levels of mycotoxins, including

  18. Assessment of chromatographic methods for the chemical stability of a new miconazole nitrate cream

    International Nuclear Information System (INIS)

    Garcia Pulpeiro, Oscar; Calzadilla Aguiar, Wendy; Rodriguez Bencomo, Wendy

    2013-01-01

    To assess the chromatographic methods for the chemical stability of a new 2 % miconazol nitrate cream. arious degradation conditions were firstly used in the raw material miconazole nitrate in order to obtain the possible degradation products of this drug and to evaluate them by thin layer chromatography-based method, which was validated to identify the degradation products in the new cream. The performance of the official method based on high resolution liquid chromatography and reported in British Pharmacopoeia 2010 was evaluated, and its selectivity against the possible degradation products were also analyzed. Both chromatographic methods were applied to the analysis of cream samples from the three pilot batches under heat stress for 30 days

  19. Underway meteorological, navigational, optical, physical, profile and time series data collected aboard NOAA Ship Bell M. Shimada in the Coastal Waters of SE Alaska and North Pacific Ocean from 2016-03-16 to 2016-03-20 (NCEI Accession 0151240)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NCEI Accession 0151240 contains raw underway meteorological, navigational, optical, physical, profile and time series data logged by the Scientific Computer System...

  20. Underway meteorological, navigational, optical, physical, profile and time series data collected aboard NOAA Ship Bell M. Shimada in the Coastal Waters of SE Alaska and North Pacific Ocean from 2014-06-24 to 2014-09-14 (NCEI Accession 0121964)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NODC Accession 0121964 contains raw underway meteorological, navigational, optical, physical, profile and time series data logged by the Scientific Computer System...

  1. Underway meteorological, navigational, optical, physical, profile and time series data collected aboard NOAA Ship Bell M. Shimada in the Coastal Waters of SE Alaska and North Pacific Ocean from 2015-02-11 to 2015-03-03 (NODC Accession 0126536)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NODC Accession 0126536 contains raw underway meteorological, navigational, optical, physical, profile and time series data logged by the Scientific Computer System...

  2. Underway meteorological, navigational, optical, physical, profile and time series data collected aboard NOAA Ship Reuben Lasker in the Coastal Waters of SE Alaska, Gulf of Alaska and others from 2015-07-09 to 2015-10-22 (NCEI Accession 0132081)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NODC Accession 0132081 contains raw underway meteorological, navigational, optical, physical, profile and time series data logged by the Scientific Computer System...

  3. Underway meteorological, navigational, optical, physical, profile and time series data collected aboard NOAA Ship Bell M. Shimada in the Coastal Waters of SE Alaska and North Pacific Ocean from 2015-06-20 to 2015-09-10 (NCEI Accession 0131258)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NODC Accession 0131258 contains raw underway meteorological, navigational, optical, physical, profile and time series data logged by the Scientific Computer System...

  4. Leveraging probabilistic peak detection to estimate baseline drift in complex chromatographic samples

    NARCIS (Netherlands)

    Lopatka, M.; Barcaru, A.; Sjerps, M.J.; Vivó-Truyols, G.

    2016-01-01

    Accurate analysis of chromatographic data often requires the removal of baseline drift. A frequently employed strategy strives to determine asymmetric weights in order to fit a baseline model by regression. Unfortunately, chromatograms characterized by a very high peak saturation pose a significant

  5. Comparison of chromatographic methods for the determination of bound glycerol in biodiesel

    Energy Technology Data Exchange (ETDEWEB)

    Foglia, T.A.; Jones, K.C.; Nunez, A.; Phillips, J.G. [U.S. Dept. of Agriculture, Agricultural Research Service, Eastern Regional Research Center, Wyndmoor, PA (United States); Mittelbach, M. [Inst. for Chemistry, Univ. of Graz, Graz (Austria)

    2004-09-01

    An important fuel criterion for biodiesel is bound glycerol, which is a function of the residual amount of triglycerides and partial glycerides in the biodiesel. Either high-temperature gas chromatography or high performance liquid chromatography can be used for determining these minor but important components in biodiesel. In this paper we have conducted a statistical study on the accuracy of the two methods for ascertaining the bound glycerol in biodiesel fuels obtained from different feedstocks. Analysis of variance showed that with one exception, namely diacylglycerols in some soy oil based biodiesel, there was no statistical difference in bound glycerol for the biodiesel samples analyzed or a difference between methods. Operationally, the high performance liquid chromatographic method is superior to the high temperature gas chromatographic method in that it requires no sample derivatization, has shorter analysis times, and is directly applicable to most biodiesel fuels. (orig.)

  6. Chromatographic separation of alkaline phosphatase from dental enamel

    DEFF Research Database (Denmark)

    Moe, D; Kirkeby, S; Salling, E

    1989-01-01

    Alkaline phosphatase (AP) was prepared from partly mineralized bovine enamel by extraction in phosphate buffer, centrifugation and various chromatographic techniques. Chromatofocusing showed that the enamel enzyme possessed five isoelectric points at the acid pH level ranging from pH 5.7 to pH 4.......4. Three enzyme peaks were eluted using low pressure chromatography with a Bio-gel column. With a HPLC gel filtration column the separation of the enamel extract resulted in only one peak with AP activity. The fractions of this peak were used to produce an antibody against bovine AP....

  7. A chromatographic objective function to characterise chromatograms with unknown compounds or without standards available.

    Science.gov (United States)

    Alvarez-Segura, T; Gómez-Díaz, A; Ortiz-Bolsico, C; Torres-Lapasió, J R; García-Alvarez-Coque, M C

    2015-08-28

    Getting useful chemical information from samples containing many compounds is still a challenge to analysts in liquid chromatography. The highest complexity corresponds to samples for which there is no prior knowledge about their chemical composition. Computer-based methodologies are currently considered as the most efficient tools to optimise the chromatographic resolution, and further finding the optimal separation conditions. However, most chromatographic objective functions (COFs) described in the literature to measure the resolution are based on mathematical models fitted with the information obtained from standards, and cannot be applied to samples with unknown compounds. In this work, a new COF based on the automatic measurement of the protruding part of the chromatographic peaks (or peak prominences) that indicates the number of perceptible peaks and global resolution, without the need of standards, is developed. The proposed COF was found satisfactory with regard to the peak purity criterion when applied to artificial peaks and simulated chromatograms of mixtures built using the information of standards. The approach was applied to mixtures of drugs containing unknown impurities and degradation products and to extracts of medicinal herbs, eluted with acetonitrile-water mixtures using isocratic and gradient elution. Copyright © 2015 Elsevier B.V. All rights reserved.

  8. New method for evaluating irreversible adsorption and stationary phase bleed in gas chromatographic capillary columns.

    Science.gov (United States)

    Wright, Bob W; Wright, Cherylyn W

    2012-10-26

    A novel method is described for the evaluation of irreversible adsorption and column bleed in gas chromatographic (GC) columns using a tandem GC approach. This work specifically determined the degree of irreversible adsorption behavior of specific sulfur and phosphorous containing test probe compounds at levels ranging from approximately 50 picograms (pg) to 1 nanogram (ng) on selected gas chromatographic columns. This method does not replace existing evaluation methods that characterize reversible adsorption but provides an additional tool. The test compounds were selected due to their ease of adsorption and their importance in the specific trace analytical detection methodology being developed. Replicate chromatographic columns with 5% phenylmethylpolysiloxane (PMS), polyethylene glycol (wax), trifluoropropylpolysiloxane (TFP), or 78% cyanopropylpolysiloxane stationary phases from a variety of vendors were evaluated. As expected, the results demonstrate that the different chromatographic phases exhibit differing degrees of irreversible adsorption behavior. The results also indicate that all manufacturers do not produce equally inert columns nor are columns from a given manufacturer identical. The wax-coated columns for the test probes used were more inert as a group than 5% PMS coated columns, and they were more reproducibly manufactured. Both TFP and 78% cyanopropylpolysiloxane columns displayed superior inertness to the test compounds compared to either 5% PMS- or wax-coated columns. Irreversible adsorption behavior was characterized for a limited range of stationary phase film thicknesses. In addition, the method was shown effective for characterizing column bleed and methods to remove bleed components. This method is useful in screening columns for demanding applications and to obtain diagnostic information related to improved preparation methods. Copyright © 2012 Elsevier B.V. All rights reserved.

  9. Principal coordinate analysis assisted chromatographic analysis of bacterial cell wall collection: A robust classification approach.

    Science.gov (United States)

    Kumar, Keshav; Cava, Felipe

    2018-04-10

    In the present work, Principal coordinate analysis (PCoA) is introduced to develop a robust model to classify the chromatographic data sets of peptidoglycan sample. PcoA captures the heterogeneity present in the data sets by using the dissimilarity matrix as input. Thus, in principle, it can even capture the subtle differences in the bacterial peptidoglycan composition and can provide a more robust and fast approach for classifying the bacterial collection and identifying the novel cell wall targets for further biological and clinical studies. The utility of the proposed approach is successfully demonstrated by analysing the two different kind of bacterial collections. The first set comprised of peptidoglycan sample belonging to different subclasses of Alphaproteobacteria. Whereas, the second set that is relatively more intricate for the chemometric analysis consist of different wild type Vibrio Cholerae and its mutants having subtle differences in their peptidoglycan composition. The present work clearly proposes a useful approach that can classify the chromatographic data sets of chromatographic peptidoglycan samples having subtle differences. Furthermore, present work clearly suggest that PCoA can be a method of choice in any data analysis workflow. Copyright © 2018 Elsevier Inc. All rights reserved.

  10. Batch-to-batch quality consistency evaluation of botanical drug products using multivariate statistical analysis of the chromatographic fingerprint.

    Science.gov (United States)

    Xiong, Haoshu; Yu, Lawrence X; Qu, Haibin

    2013-06-01

    Botanical drug products have batch-to-batch quality variability due to botanical raw materials and the current manufacturing process. The rational evaluation and control of product quality consistency are essential to ensure the efficacy and safety. Chromatographic fingerprinting is an important and widely used tool to characterize the chemical composition of botanical drug products. Multivariate statistical analysis has showed its efficacy and applicability in the quality evaluation of many kinds of industrial products. In this paper, the combined use of multivariate statistical analysis and chromatographic fingerprinting is presented here to evaluate batch-to-batch quality consistency of botanical drug products. A typical botanical drug product in China, Shenmai injection, was selected as the example to demonstrate the feasibility of this approach. The high-performance liquid chromatographic fingerprint data of historical batches were collected from a traditional Chinese medicine manufacturing factory. Characteristic peaks were weighted by their variability among production batches. A principal component analysis model was established after outliers were modified or removed. Multivariate (Hotelling T(2) and DModX) control charts were finally successfully applied to evaluate the quality consistency. The results suggest useful applications for a combination of multivariate statistical analysis with chromatographic fingerprinting in batch-to-batch quality consistency evaluation for the manufacture of botanical drug products.

  11. Underway meteorological, navigational, optical, physical and time series data collected aboard NOAA Ship Oscar Dyson in the Coastal Waters of SE Alaska, Gulf of Alaska and North Pacific Ocean from 2013-09-24 to 2013-11-03 (NODC Accession 0124206)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NODC Accession 0124206 contains raw underway meteorological, navigational, optical, physical and time series data logged by the Scientific Computer System (SCS)...

  12. Underway meteorological, navigational, optical, physical and time series data collected aboard NOAA Ship Oscar Dyson in the Coastal Waters of SE Alaska, Gulf of Alaska and North Pacific Ocean from 2015-01-24 to 2015-01-30 (NODC Accession 0126876)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NODC Accession 0126876 contains raw underway meteorological, navigational, optical, physical and time series data logged by the Scientific Computer System (SCS)...

  13. Underway meteorological, navigational, optical, physical and time series data collected aboard NOAA Ship Oscar Dyson in the Coastal Waters of SE Alaska, Gulf of Alaska and North Pacific Ocean from 2013-04-04 to 2013-04-15 (NODC Accession 0124185)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NODC Accession 0124185 contains raw underway meteorological, navigational, optical, physical and time series data logged by the Scientific Computer System (SCS)...

  14. Underway meteorological, navigational, optical, physical and time series data collected aboard NOAA Ship Oscar Dyson in the Coastal Waters of SE Alaska, Gulf of Alaska and North Pacific Ocean from 2016-01-30 to 2016-02-09 (NCEI Accession 0150729)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NCEI Accession 0150729 contains raw underway meteorological, navigational, optical, physical and time series data logged by the Scientific Computer System (SCS)...

  15. Underway meteorological, navigational, optical, physical and time series data collected aboard NOAA Ship Oscar Dyson in the Coastal Waters of SE Alaska, Gulf of Alaska and North Pacific Ocean from 2016-02-03 to 2016-02-09 (NCEI Accession 0150730)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NCEI Accession 0150730 contains raw underway meteorological, navigational, optical, physical and time series data logged by the Scientific Computer System (SCS)...

  16. Underway meteorological, navigational, optical, physical and time series data collected aboard NOAA Ship Oscar Dyson in the Coastal Waters of SE Alaska, Gulf of Alaska and North Pacific Ocean from 2013-01-28 to 2013-02-03 (NODC Accession 0124297)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NODC Accession 0124297 contains raw underway meteorological, navigational, optical, physical and time series data logged by the Scientific Computer System (SCS)...

  17. Chromatographic enrichment of isotopes in hydrogen and water samples on palladium

    International Nuclear Information System (INIS)

    Andreev, B.M.; Polevoi, A.S.; Perevezentsev, A.N.

    1987-01-01

    Data on the isotopic enrichment of hydrogen and water samples by chromatography on palladium have been analyzed. Experimental data on the effect of temperature, hydrogen flow, volume of the enriched fraction, and length of the chromatographic column on the degree of separation attainable in the column have been obtained. It has been shown that the maximum separation achievable (regardless of the type of the isotope mixture) at 273 K falls with increase of hydrogen flow and volume of the enriched gas fraction recoverable from the column. A separation degree of ∼ 1040 has been achieved for a mixture of protium and deuterium in a 10-mm wide and 0.6-m long chromatographic column packed with palladium black with a grain size of 0.2-0.5 mm at 273 K and a specific hydrogen flow of 1.22 mole/m 2 x sec. For a protium-tritium mixture a separation degree of ∼ 90 has been reached in a similar column at 273 K and a specific hydrogen flow of 0.4 mole/m 2 x sec

  18. Sea surface temperature and salinity from the Global Ocean Surface Underway Data (GOSUD) from 1980-01-03 to present

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This collection contains the Global Ocean Surface Underway Data (GOSUD) from 1980-01-03 to present as submitted to NOAA/NCEI. The data includes information about sea...

  19. Underway meteorological, navigational, physical and time series data collected aboard NOAA Ship Ronald H. Brown in the Coastal Waters of SE Alaska, Gulf of Alaska and North Pacific Ocean from 2015-07-14 to 2015-08-03 (NCEI Accession 0130369)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NCEI Accession 0130369 contains raw underway meteorological, navigational, physical and time series data logged by the Scientific Computer System (SCS) aboard NOAA...

  20. Derivatization reactions in the gas—liquid chromatographic analysis of drugs in biological fluids

    NARCIS (Netherlands)

    Hulshoff, A.; Lingeman, H.

    1984-01-01

    Alkylation, acylation, silylation and other derivatization reactions applied to the gas chromatographic analysis of drugs in biological matrices are reviewed. Reaction conditions are discussed in relation to reaction mechanisms. Detector-oriented labelling of drugs, and derivatization with chiral

  1. Liquid chromatographic determination of saccharin in beverages and desserts: complementary collaborative study.

    Science.gov (United States)

    Sjöberg, A M

    1988-01-01

    A complementary collaborative study was conducted on a liquid chromatographic method for determination of saccharin in accordance with the latest international recommendations. One industrial and 6 official food control laboratories analyzed 3 samples of a juice, a soft drink, and a dessert at concentration levels of 26-90 mg/L, 33-73 mg/L, and 56-147 mg/kg, respectively. Blind duplicates and a blank were supplied for each type of material at each concentration level. The beverage was chromatographed directly and the dessert was extracted with ethanol before chromatography. Average recoveries were 95-107%. The reproducibility relative standard deviations were 6.4-7.3% for the juice, 9.2-20.6% for the soft drink, and 13.4-16.2% for the dessert. The outlier percentage was 14.3%. The results were compared with those of an earlier collaborative study by Nordic laboratories and with general collaborative results obtained by AOAC.

  2. Mars Solar Balloon Landed Gas Chromatograph Mass Spectrometer

    Science.gov (United States)

    Mahaffy, P.; Harpold, D.; Niemann, H.; Atreya, S.; Gorevan, S.; Israel, G.; Bertaux, J. L.; Jones, J.; Owen, T.; Raulin, F.

    1999-01-01

    A Mars surface lander Gas Chromatograph Mass Spectrometer (GCMS) is described to measure the chemical composition of abundant and trace volatile species and isotope ratios for noble gases and other elements. These measurements are relevant to the study of atmospheric evolution and past climatic conditions. A Micromission plan is under study where a surface package including a miniaturized GCMS would be delivered to the surface by a solar heated hot air balloon based system. The balloon system would be deployed about 8 km above the surface of Mars, wherein it would rapidly fill with Martian atmosphere and be heated quickly by the sun. The combined buoyancy and parachuting effects of the solar balloon result in a surface package impact of about 5 m/sec. After delivery of the package to the surface, the balloon would ascend to about 4 km altitude, with imaging and magnetometry data being taken for the remainder of the daylight hours as the balloon is blown with the Martian winds. Total atmospheric entry mass of this mission is estimated to be approximately 50 kg, and it can fit as an Ariane 5 piggyback payload. The GCMS would obtain samples directly from the atmosphere at the surface and also from gases evolved from solid phase material collected from well below the surface with a Sample Acquisition and Transport Mechanism (SATM). The experiment envisioned in the Mars Micromission described would obtain samples from a much greater depth of up to one meter below the surface, and would search for organic molecules trapped in ancient stratified layers well below the oxidized surface. Insitu instruments on upcoming NASA missions working in concert with remote sensing measurement techniques have the potential to provide a more detailed investigation of mineralogy and the extent of simple volatiles such as CO2 and H2O in surface and subsurface solid phase materials. Within the context of subsequent mission opportunities such as those provided by the Ariane 5 piggyback

  3. Underway pCO2 and other measurements aboard NOAA Ship Ronald H. Brown during the 2007 cruises (NODC Accession 0081023)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NCEI Accession 0081023 includes Surface underway, chemical, meteorological, optical and physical data collected from NOAA Ship RONALD H. BROWN in the Caribbean Sea,...

  4. Improvement in gradient ion chromatographic method for trace anions and organic acids in the PWR nuclear power plant

    International Nuclear Information System (INIS)

    Junlowjiraya, V.

    1989-01-01

    In a nuclear power plant the use of high quality water is very important to minimize corrosion and downtime of a plant system. To evaluate the quality of water the most widely used instrument is a conductivity analyzer. However, conductivity monitor is nonspecific, the conductivity signal cannot give information about what species or impurities are presented in the water, steam, and condensate. To determine these impurities qualitatively and quantitatively, the ion chromatography is an effective technique. This presentation demonstrates an improvement of gradient ion chromatographic technique to solve lithium interference in the borated samples. The data acquisition system and computer automation setup for the analysis are also discussed

  5. The chromatographic behavior of arsenic compounds on anion exchange columns with binary organic acids as mobile phases

    Energy Technology Data Exchange (ETDEWEB)

    Zheng, J.; Goessler, W.; Kosmus, W. [Graz Univ. (Austria). Inst. fuer Analytische Chemie

    1998-03-01

    Identification and quantification of arsenic compounds was performed with high-performance liquid chromatography (HPLC) and flame atomic absorption spectrometry (FAAS) as element-specific detector. Arsenous acid, methylarsonic acid, dimethylarsinic acid, arsenic acid, arsenobetaine, and arsenocholine were separated on two anion-exchange columns (Synchropak Q 300 and PRP-X 100) with different binary organic acids as mobile phases. The influence of chromatographic parameters, such as pH and the concentration of the mobile phase were investigated. An unusual chromatographic behavior of arsenous acid was observed when tartaric acid was used as mobile phase. (orig.)

  6. Test plan for demonstrating plutonium extraction from 10-L solutions using EIChrom extraction chromatographic resins

    International Nuclear Information System (INIS)

    Barney, G.S.

    1994-01-01

    Corrosive plutonium solutions stored in 10-L containers at the Plutonium Finishing Plant must be treated to convert the plutonium to a safe, solid form for storage and to remove the americium so that radiation exposure can be reduced. Extraction chromatographic resins will be tested for separating plutonium from these solutions in the laboratory. Separation parameters will be developed during the testing for large scale processing of the 10-L solutions and solutions of similar composition. Use of chromatographic resins will allow plutonium separation with minimum of chemical addition to the feed and without the need for plutonium valence adjustment. The separated plutonium will be calcined to plutonium oxide by direct solution calcination

  7. Warping methods for spectroscopic and chromatographic signal alignment: A tutorial

    Energy Technology Data Exchange (ETDEWEB)

    Bloemberg, Tom G., E-mail: T.Bloemberg@science.ru.nl [Radboud University Nijmegen, Institute for Molecules and Materials, Heyendaalseweg 135, 6525 AJ Nijmegen (Netherlands); Radboud University Nijmegen, Education Institute for Molecular Sciences, Heyendaalseweg 135, 6525 AJ Nijmegen (Netherlands); Gerretzen, Jan; Lunshof, Anton [Radboud University Nijmegen, Institute for Molecules and Materials, Heyendaalseweg 135, 6525 AJ Nijmegen (Netherlands); Wehrens, Ron [Centre for Research and Innovation, Fondazione Edmund Mach, Via E. Mach, 1, 38010 San Michele all’Adige, TN (Italy); Buydens, Lutgarde M.C. [Radboud University Nijmegen, Institute for Molecules and Materials, Heyendaalseweg 135, 6525 AJ Nijmegen (Netherlands)

    2013-06-05

    Highlights: •The concepts of warping and alignment are introduced. •The most important warping methods are critically reviewed and explained. •Reference selection, evaluation and place of warping in preprocessing are discussed. •Some pitfalls, especially for LC–MS and similar data, are addressed. •Examples are provided, together with programming scripts to rework and extend them. -- Abstract: Warping methods are an important class of methods that can correct for misalignments in (a.o.) chemical measurements. Their use in preprocessing of chromatographic, spectroscopic and spectrometric data has grown rapidly over the last decade. This tutorial review aims to give a critical introduction to the most important warping methods, the place of warping in preprocessing and current views on the related matters of reference selection, optimization, and evaluation. Some pitfalls in warping, notably for liquid chromatography–mass spectrometry (LC–MS) data and similar, will be discussed. Examples will be given of the application of a number of freely available warping methods to a nuclear magnetic resonance (NMR) spectroscopic dataset and a chromatographic dataset. As part of the Supporting Information, we provide a number of programming scripts in Matlab and R, allowing the reader to work the extended examples in detail and to reproduce the figures in this paper.

  8. Partition efficiencies of newly fabricated universal high-speed counter-current chromatograph for separation of two different types of sugar derivatives with organic-aqueous two-phase solvent systems

    Science.gov (United States)

    Shinomiya, Kazufusa; Sato, Kazuki; Yoshida, Kazunori; Tokura, Koji; Maruyama, Hiroshi; Yanagidaira, Kazuhiro; Ito, Yoichiro

    2013-01-01

    Universal high-speed counter-current chromatograph (HSCCC) was newly designed and fabricated in our laboratory. It holds a set of four column holders symmetrically around the rotary frame at a distance of 11.2 cm from the central axis. By engaging the stationary gear on the central axis of the centrifuge to the planetary gears on the column holder shaft through a set of idle gears, two pairs of diagonally located column holders simultaneously rotate about their own axes in the opposite directions: one forward (type-J planetary motion) and the other backward (type-I planetary motion) each synchronously with the revolution. Using the eccentric coil assembly, partition efficiencies produced by these two planetary motions were compared on the separation of two different types of sugar derivatives (4-methylumbelliferyl and 5-bromo-4-chloro-3-indoxyl sugar derivatives) using organic-aqueous two-phase solvent systems composed of n-hexane/ethyl acetate/1-butanol/methanol/water and aqueous 0.1 M sodium tetraborate, respectively. With lower phase mobile, better peak resolution was obtained by the type-J forward rotation for both samples probably due to higher retention of the stationary phase. With upper phase mobile, however, similar peak resolutions were obtained between these two planetary motions for both sugar derivatives. The overall results indicate that the present universal HSCCC is useful for counter-current chromatographic separation since each planetary motion has its specific applications: e.g., vortex CCC by the type-I planetary motion and HSCCC by the type-J planetary motion both for separation of various natural and synthetic products. PMID:24267319

  9. Underway meteorological, navigational, optical, physical, profile and time series data collected aboard NOAA Ship Bell M. Shimada in the Coastal Waters of Southeast Alaska and British Columbia and North Pacific Ocean from 2016-06-30 to 2016-08-14 (NCEI Accession 0162237)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NCEI Accession 0162237 contains raw underway meteorological, navigational, optical, physical, profile and time series data logged by the Scientific Computer System...

  10. Underway meteorological, navigational, optical, physical and time series data collected aboard NOAA Ship Oscar Dyson in the Coastal Waters of Southeast Alaska and British Columbia, Gulf of Alaska and North Pacific Ocean from 2017-01-26 to 2017-02-01 (NCEI Accession 0165022)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NCEI Accession 0165022 contains raw underway meteorological, navigational, optical, physical and time series data logged by the Scientific Computer System (SCS)...

  11. Underway meteorological, navigational, optical, physical and time series data collected aboard NOAA Ship Oscar Dyson in the Coastal Waters of Southeast Alaska and British Columbia, Gulf of Alaska and North Pacific Ocean from 2016-10-13 to 2016-10-19 (NCEI Accession 0165091)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NCEI Accession 0165091 contains raw underway meteorological, navigational, optical, physical and time series data logged by the Scientific Computer System (SCS)...

  12. Underway meteorological, navigational, optical, physical, profile and time series data collected aboard NOAA Ship Bell M. Shimada in the Coastal Waters of Southeast Alaska and British Columbia and North Pacific Ocean from 2015-09-16 to 2015-10-13 (NCEI Accession 0135733)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NCEI Accession 0135733 contains raw underway meteorological, navigational, optical, physical, profile and time series data logged by the Scientific Computer System...

  13. Application of extraction-chromatographic concentration to atomic absorption determination of lead and cadmium in drinking and sea water

    International Nuclear Information System (INIS)

    Bol'shova, T.A.; Agapkina, G.I.; Ershova, N.I.; Narankho, K.E.

    1988-01-01

    To increase the detection limits for lead and cadmium atomic-absorption determination in natural waters methods of extraction-chromatographic concentration of these metals using tri-n-octylamine (TOA) on polytetrafluoroethylene (PTFE) is developed. Chromatograpy was carried out from 1.5-2.0 M HBr solutions. For cadmium and lead elution acetic acid was used. It is shown that extraction-chromatographic concentration permits to decrease limits of metal atomic-absorption detection by 10 3 with the 500 ml volume sample analysis

  14. Chemometric approach for development, optimization, and validation of different chromatographic methods for separation of opium alkaloids.

    Science.gov (United States)

    Acevska, J; Stefkov, G; Petkovska, R; Kulevanova, S; Dimitrovska, A

    2012-05-01

    The excessive and continuously growing interest in the simultaneous determination of poppy alkaloids imposes the development and optimization of convenient high-throughput methods for the assessment of the qualitative and quantitative profile of alkaloids in poppy straw. Systematic optimization of two chromatographic methods (gas chromatography (GC)/flame ionization detector (FID)/mass spectrometry (MS) and reversed-phase (RP)-high-performance liquid chromatography (HPLC)/diode array detector (DAD)) for the separation of alkaloids from Papaver somniferum L. (Papaveraceae) was carried out. The effects of various conditions on the predefined chromatographic descriptors were investigated using chemometrics. A full factorial linear design of experiments for determining the relationship between chromatographic conditions and the retention behavior of the analytes was used. Central composite circumscribed design was utilized for the final method optimization. By conducting the optimization of the methods in very rational manner, a great deal of excessive and unproductive laboratory research work was avoided. The developed chromatographic methods were validated and compared in line with the resolving power, sensitivity, accuracy, speed, cost, ecological aspects, and compatibility with the poppy straw extraction procedure. The separation of the opium alkaloids using the GC/FID/MS method was achieved within 10 min, avoiding any derivatization step. This method has a stronger resolving power, shorter analysis time, better cost/effectiveness factor than the RP-HPLC/DAD method and is in line with the "green trend" of the analysis. The RP-HPLC/DAD method on the other hand displayed better sensitivity for all tested alkaloids. The proposed methods provide both fast screening and an accurate content assessment of the six alkaloids in the poppy samples obtained from the selection program of Papaver strains.

  15. Chromatographic retention and structure roofing tile effect of isomers and its fine structure

    NARCIS (Netherlands)

    Walraven, J.J.; Ladon, A.W.; Keulemans, A.I.M.

    1968-01-01

    Logarithmic plots of gas chromatographic retention data for different classes of compds. on different pairs of stationary phases were constructed. A remarkable effect was found. Isomers are spread along parallel lines in a repeated pattern, forming a \\"roofing-tile\\" series. The scattering of points

  16. Underway pCO2 Measurements in Surface Waters and the Atmosphere During the CGC Healy 2016 Expeditions (NCEI Accession 0166631)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NCEI Accession 0166631 includes Surface underway data collected from CGC Healy in the North Pacific Ocean, Bering Sea, Chukchi Sea and Arctic Ocean from 2016-06-30...

  17. Chromatographic and electrophoretic approaches in ink analysis.

    Science.gov (United States)

    Zlotnick, J A; Smith, F P

    1999-10-15

    Inks are manufactured from a wide variety of substances that exhibit very different chemical behaviors. Inks designed for use in different writing instruments or printing methods have quite dissimilar components. Since the 1950s chromatographic and electrophoretic methods have played important roles in the analysis of inks, where compositional information may have bearing on the investigation of counterfeiting, fraud, forgery, and other crimes. Techniques such as paper chromatography and electrophoresis, thin-layer chromatography, high-performance liquid chromatography, gas chromatography, gel electrophoresis, and the relatively new technique of capillary electrophoresis have all been explored as possible avenues for the separation of components of inks. This paper reviews the components of different types of inks and applications of the above separation methods are reviewed.

  18. Gas chromatographic measurement in water-steam circuits

    International Nuclear Information System (INIS)

    Zschetke, J.; Nieder, R.

    1984-01-01

    A gas chromatographic technique for measurements in water-steam circuits, which has been well known for many years, has been improved by design modifications. A new type of equipment developed for special measuring tasks on nuclear engineering plant also has a general application. To date measurements have been carried out on the ''Otto Hahn'' nuclear powered ship, on the KNK and AVR experimental nuclear power plants at Karlsruhe and Juelich respectively and on experimental boiler circuits. The measurements at the power plants were carried out under different operating conditions. In addition measurements during the alkali operating mode and during combined cycle operation were carried out on the AVR reactor. It has been possible to draw new conclusion from the many measurements undertaken. (orig.) [de

  19. Chromatographic analysis and purification of multiply tritium-labelled eicosanoids

    International Nuclear Information System (INIS)

    Shevchenko, V.P.; Nagaev, I.Yu.; Myasoedov, N.F.

    1988-01-01

    A comparative study of different chromatographic techniques (gas-liquid (GLC), thin-layer (TLC), liquid (LC), high-pressure liquid (HPLC) chromatography) is presented. They were applied to the analysis and preparative purification of tritium-labelled eicosanoids with a molar radioactivity of 1.8-8.8 TBq/mmol, obtained by selective hydrogenation and by chemical or enzymic methods. The possibility of analyzing reaction mixtures and isolating individual multiply labelled eicosanoids with a chemical and radiochemical purity of 95-98% was demonstrated. Special features of HPLC for high molar radioactivity eicosanoids are considered. (author) 9 refs.; 6 tabs

  20. Probabilistic classification method on multi wavelength chromatographic data for photosynthetic pigments identification

    Science.gov (United States)

    Prilianti, K. R.; Setiawan, Y.; Indriatmoko, Adhiwibawa, M. A. S.; Limantara, L.; Brotosudarmo, T. H. P.

    2014-02-01

    Environmental and health problem caused by artificial colorant encourages the increasing usage of natural colorant nowadays. Natural colorant refers to the colorant that is derivate from living organism or minerals. Extensive research topic has been done to exploit these colorant, but recent data shows that only 0.5% of the wide range of plant pigments in the earth has been exhaustively used. Hence development of the pigment characterization technique is an important consideration. High-performance liquid chromatography (HPLC) is a widely used technique to separate pigments in a mixture and identify it. In former HPLC fingerprinting, pigment characterization was based on a single chromatogram from a fixed wavelength (one dimensional) and discard the information contained at other wavelength. Therefore, two dimensional fingerprints have been proposed to use more chromatographic information. Unfortunately this method leads to the data processing problem due to the size of its data matrix. The other common problem in the chromatogram analysis is the subjectivity of the researcher in recognizing the chromatogram pattern. In this research an automated analysis method of the multi wavelength chromatographic data was proposed. Principal component analysis (PCA) was used to compress the data matrix and Maximum Likelihood (ML) classification was applied to identify the chromatogram pattern of the existing pigments in a mixture. Three photosynthetic pigments were selected to show the proposed method. Those pigments are β-carotene, fucoxanthin and zeaxanthin. The result suggests that the method could well inform the existence of the pigments in a particular mixture. A simple computer application was also developed to facilitate real time analysis. Input of the application is multi wavelength chromatographic data matrix and the output is information about the existence of the three pigments.

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