Sample records for chromatography paper

  1. Fun with Paper Chromatography. (United States)

    Coleman, Dava; Hounshell, Paul B.


    Discusses paper chromatographic techniques and provides examples of typical classroom activities. Includes description of retardation values obtained during chromatography exercises and suggests using them for math lessons. (JN)

  2. Extending Paper Chromatography Inquiry (United States)

    Finson, Kevin


    One of the "good old" standard activities middle school students seem to enjoy is paper chromatography. The procedures and materials needed are relatively simple and the results can be colorful. All too often, the activity ends just after these colorful results are obtained, cutting short the potential it holds for some further inquiry. With some…

  3. Thin-Layer and Paper Chromatography. (United States)

    Sherma, Joseph; Fried, Bernard


    Reviews literature on chromatography examining: books, reviews, student experiments; chromatographic systems, techniques, apparatus; detecting and identification of separated zones; preparative chromatography and radiochromatography; and applications related to specific materials (such as acids, alcohols, amino acids, antibiotics, enzymes, dyes,…

  4. The Ideal Solvent for Paper Chromatography of Food Dyes. (United States)

    Markow, Peter G.


    Uses paper chromatography with food dyes to provide a simple and inexpensive basis for teaching chromatography. Provides experimental methodology and tabled results. Includes a solvent system comparison (Rf) for seven dyes and twenty-two solvents. (MVL)

  5. Peak broadening in paper chromatography and related techniques : IV. The mechanism of the mass transfer term in paper chromatography

    NARCIS (Netherlands)

    Ligny, C.L. de; Remijnse, A.G.


    The mechanism of peak broadening in paper chromatography is investigated by comparing the peak widths obtained in chromatography with those caused only by diffusion, for a set of amino acids of widely differing RF values and with eight kinds of Whatman paper. The results show that longitudinal diff

  6. Electronic circuitry used to automate paper chromatography (United States)

    Steffensen, G. R.


    Electronic circuit is used in a paper chromatograph instrument that has excellent sensitivity and furnishes a printed record of each test. The circuit measures and records changes in conductivity in a strip of chromatographic paper as different solutions are placed on it.

  7. Detection of Two Phosphorus Containing Anacardic Compounds by Paper Chromatography

    Directory of Open Access Journals (Sweden)

    K. Sridharan


    Full Text Available A method based on paper chromatography for detection and determination of tris-tetrahydroanacardoxy phosphite and tris-(2 terat-hydroanacardoxyethyl-phosphite. The Rf values for these compounds in four solvent systems are recorded.

  8. Chromatography. (United States)

    Brantley, L. Reed, Sr.; Demanche, Edna L.; Klemm, E. Barbara; Kyselka, Will; Phillips, Edwin A.; Pottenger, Francis M.; Yamamoto, Karen N.; Young, Donald B.

    This booklet presents some activities on chromatography. Directions for preparing leaf pigment extracts using alcohol are given, and paper chromatography and thin-layer chromatography are described as modifications of the basic principles of chromatography. (KHR)

  9. Paper SERS chromatography for detection of trace analytes in complex samples (United States)

    Yu, Wei W.; White, Ian M.


    We report the application of paper SERS substrates for the detection of trace quantities of multiple analytes in a complex sample in the form of paper chromatography. Paper chromatography facilitates the separation of different analytes from a complex sample into distinct sections in the chromatogram, which can then be uniquely identified using SERS. As an example, the separation and quantitative detection of heroin in a highly fluorescent mixture is demonstrated. Paper SERS chromatography has obvious applications, including law enforcement, food safety, and border protection, and facilitates the rapid detection of chemical and biological threats at the point of sample.

  10. Normal- and reverse-phase paper chromatography of leaf extracts of dandelions


    Du Toit, Maria H.; Eggen, Per-Odd; Kvittigen, Lise; Partali, Vassilia; Schmid, Rudolf


    This demonstration describes how normal and reverse phase chromatography can be illustrated using only chromatography paper for the separation of extracts of dandelions.

  11. Virtual Practice of Biochemistry: Ascendant Chromatography on Paper of Amino acids.


    Zanatta,G.; De Moraes, C G; E.R. Zimmer; E. Ewald; Pettenuzzo,L.F.; Salbego, C. G.; V.M.T. Trindade


    Chromatography is a method used for analyses of mixture components based on different criteria: adsorbility, solubility, molecular mass, ionic charge and affinity. It is an important subject of Biochemistry. This work reports the development and the validation of a software that simulated a laboratory activity named Ascendant Chromatography on Paper of Aminoacids. The organization and the multimedia material collection were done during the 2008/2 semester. The most representative images were ...

  12. Impedance Analysis of Colloidal Gold Nanoparticles in Chromatography Paper for Quantitation of an Immunochromatographic Assay. (United States)

    Hori, Fumitaka; Harada, Yuji; Kuretake, Tatsumi; Uno, Shigeyasu


    A detection method of gold nanoparticles in chromatography paper has been developed for a simple, cost-effective and reliable quantitation of immunochromatographic strip test. The time courses of the solution resistance in chromatography paper with the gold nanoparticles solution are electrochemically measured by chrono-impedimetry. The dependence of the solution resistance on the concentration of gold nanoparticles has been successfully observed. The main factor to increase the solution resistance may be obstruction of the ion transport due to the presence of gold nanoparticles. The existence of gold nanoparticles with 1.92 × 10(9) particles/mL in an indistinctly-colored chromatography paper is also identified by a solution resistance measurement. This indicates that the solution resistance assay has the potential to lower the detection limit of the conventional qualitative assay.

  13. Pre-staining paper chromatography method for quantification of gamma-aminobutyric acid. (United States)

    Li, Haixing; Qiu, Ting; Cao, Yusheng; Yang, Jiyan; Huang, Zhibing


    The routine method of paper chromatography includes five steps: spotting, separating, drying, spraying/immersing and color development. In this paper, a pre-staining paper chromatography which only consisted of spotting, separating and color development was developed for quantitative analysis of gamma-aminobutyric acid. Compared to the routine paper chromatography, the improved method is clean, rapid, inexpensive and reproducible. The effects of ninhydrin concentration, color temperature, color time and Cu(2+) concentration on the color yield in the ninhydrin reaction were optimized. And then the pre-staining paper chromatography coupled with vis spectrophotometry was applied to gamma-aminobutyric acid quantification. The results indicated that the limit of detection was 0.05 mg mL(-1) and the linear range was from 0.5 to 20.0 mg mL(-1). Furthermore, an excellent correlation coefficient was observed with an R(2)=0.998. The method is accurate (RSD<2.64%), and has good recoveries (102.7-103.9%). The validation of the modified technique was verified by a HPLC method.

  14. The Write Stuff: Using Paper Chromatography To Separate an Ink Mixture. (United States)

    Journal of Chemical Education, 2000


    Presents an activity that is a qualitative version of the standard paper chromatography experiment. This activity introduces students to methods of selecting the best solvent for a separation and allows them to consider the effects of adding acid and base. (WRM)

  15. Peak broadening in paper chromatography and related techniques : V. Conditions for minimum separation time

    NARCIS (Netherlands)

    Lygny, C.L. de; Kok, E.C.M.


    In paper and thin-layer chromatography peak broadening is a function of the mean flow rate of the eluent, which in turn is a function of the distances of the starting point and solvent front from the eluent in the tank. Starting from the relationship between peak broadening and the positions of sta

  16. Poliovirus sampling by using sodium dodecyl sulfate/EDTA-pretreated chromatography paper strips. (United States)

    Maes, Piet; Van Doren, Els; Denys, Barbara; Thoelen, Inge; Rahman, Mustafizur; Vijgen, Leen; Van Ranst, Marc


    To achieve the goal of poliovirus eradication, surveillance of endemic areas is a crucial step in the poliovirus eradication program. Currently, six countries still have endemic poliovirus. We have tested a novel method which uses SDS/EDTA-treated chromatography paper strips to collect and transport poliovirus-containing stool samples. The SDS/EDTA-treated paper strips were soaked with different dilutions of poliovirus-containing feces and stored at different temperatures. After storing the SDS/EDTA paper strips for 5 months at 37 degrees C, poliovirus RNA could be successfully amplified using RT-PCR. Infectivity of wild-type poliovirus type 1, 2, and 3 was lost upon contact with the SDS/EDTA-treated strips. This easy, inexpensive, and biosafe chromatography paper strip method for the collection and transportation of poliovirus samples can be of use in poliovirus surveillance and polio vaccination programs.

  17. Chromatography paper as a low-cost medium for accurate spectrophotometric assessment of blood hemoglobin concentration. (United States)

    Bond, Meaghan; Elguea, Carlos; Yan, Jasper S; Pawlowski, Michal; Williams, Jessica; Wahed, Amer; Oden, Maria; Tkaczyk, Tomasz S; Richards-Kortum, Rebecca


    Anemia affects a quarter of the world's population, and a lack of appropriate diagnostic tools often prevents treatment in low-resource settings. Though the HemoCue 201+ is an appropriate device for diagnosing anemia in low-resource settings, the high cost of disposables ($0.99 per test in Malawi) limits its availability. We investigated using spectrophotometric measurement of blood spotted on chromatography paper as a low-cost (paper, and a bench-top spectrophotometer validated the approach before the development of a low-cost reader. We optimized impregnating paper with chemicals to lyse red blood cells, paper type, drying time, wavelengths measured, and sensitivity to variations in volume of blood, and we validated our approach using patient samples. Lysing the blood cells with sodium deoxycholate dried in Whatman Chr4 chromatography paper gave repeatable results, and the absorbance difference between 528 nm and 656 nm was stable over time in measurements taken up to 10 min after sample preparation. The method was insensitive to the amount of blood spotted on the paper over the range of 5 μL to 25 μL. We created a low-cost, handheld reader to measure the transmission of paper cuvettes at these optimal wavelengths. Training and validating our method with patient samples on both the spectrometer and the handheld reader showed that both devices are accurate to within 2 g dL(-1) of the HemoCue device for 98% and 95% of samples, respectively.

  18. An Electrochemical Gas Biosensor Based on Enzymes Immobilized on Chromatography Paper for Ethanol Vapor Detection. (United States)

    Kuretake, Tatsumi; Kawahara, Shogo; Motooka, Masanobu; Uno, Shigeyasu


    This paper presents a novel method of fabricating an enzymatic biosensor for breath analysis using chromatography paper as enzyme supporting layer and a liquid phase layer on top of screen printed carbon electrodes. We evaluated the performance with ethanol vapor being one of the breathing ingredients. The experimental results show that our sensor is able to measure the concentration of ethanol vapor within the range of 50 to 500 ppm. These results suggest the ability of detecting breath ethanol, and it can possibly be applied as a generic vapor biosensor to a wide range of diseases.

  19. Determination of cocaine in brazilian paper currency by capillary gas chromatography/mass spectrometry

    Directory of Open Access Journals (Sweden)

    Enrico Di Donato


    Full Text Available The presence of illicit drugs such as cocaine and marijuana in US paper currency is very well demonstrated. However, there is no published study describing the presence of cocaine and/or other illicit drugs in Brazilian paper currency. In this study, Brazilian banknotes were collected from nine cities, extracted and analyzed by capillary gas chromatography/mass spectrometry, in order to investigate the presence of cocaine. Bills were extracted with deionized water followed by ethyl acetate. Results showed that 93% of the bills presented cocaine in a concentration range of 2.38-275.10 µg/bill.

  20. Thin layer chromatography coupled to paper spray ionization mass spectrometry for cocaine and its adulterants analysis. (United States)

    De Carvalho, Thays C; Tosato, Flavia; Souza, Lindamara M; Santos, Heloa; Merlo, Bianca B; Ortiz, Rafael S; Rodrigues, Rayza R T; Filgueiras, Paulo R; França, Hildegardo S; Augusti, Rodinei; Romão, Wanderson; Vaz, Boniek G


    Thin layer chromatography (TLC) is a simple and inexpensive type of chromatography that is extensively used in forensic laboratories for drugs of abuse analysis. In this work, TLC is optimized to analyze cocaine and its adulterants (caffeine, benzocaine, lidocaine and phenacetin) in which the sensitivity (visual determination of LOD from 0.5 to 14mgmL(-1)) and the selectivity (from the study of three different eluents: CHCl3:CH3OH:HCOOHglacial (75:20:5v%), (C2H5)2O:CHCl3 (50:50v%) and CH3OH:NH4OH (100:1.5v%)) were evaluated. Aiming to improve these figures of merit, the TLC spots were identified and quantified (linearity with R(2)>0.98) by the paper spray ionization mass spectrometry (PS-MS), reaching now lower LOD values (>1.0μgmL(-1)). The method developed in this work open up perspective of enhancing the reliability of traditional and routine TLC analysis employed in the criminal expertise units. Higher sensitivity, selectivity and rapidity can be provided in forensic reports, besides the possibility of quantitative analysis. Due to the great simplicity, the PS(+)-MS technique can also be coupled directly to other separation techniques such as the paper chromatography and can still be used in analyses of LSD blotter, documents and synthetic drugs.

  1. High-performance liquid chromatography determination of dapsone, monoacetyldapsone, and pyrimethamine in filter paper blood spots

    DEFF Research Database (Denmark)

    Rønn, A M; Lemnge, M M; Angelo, H R


    A high-performance liquid chromatography method for the simultaneous analysis of dapsone (DDS), the major metabolite of DDS, monoacetyldapsone (MADDS), and pyrimethamine (PYR) was modified for capillary blood samples obtained by finger prick and dried on filter paper. Limit of quantitation using...... 150 microliters whole blood dried on filter paper was found to be 20 ng/ml for DDS and PYR and 15 ng/ml for MADDS (precision ... paper method and the original whole-blood method was almost comparable. Standardization could therefore be obtained by the more simple whole-blood method. Dried filter paper samples stored at 19-22 degrees C were stable for months and for 2 weeks stored at 35 degrees C. The concentrations...

  2. Peak broadening in paper chromatography and related techniques : III. Peak broadening in thin-layer chromatography on cellulose powder

    NARCIS (Netherlands)

    Ligny, C.L. de; Remijnse, A.G.


    The mechanism of peak broadening in thin-layer chromatography on cellulose powder was investigated by comparing the peak widths obtained in chromatography with those caused only by diffusion in the cellulose powder, for a set of amino acids of widely differing RF values and six kinds of cellulose po

  3. Virtual Practice of Biochemistry: Ascendant Chromatography on Paper of Amino acids.

    Directory of Open Access Journals (Sweden)

    G. Zanatta


    Full Text Available Chromatography is a method used for analyses of mixture components based on different criteria: adsorbility, solubility, molecular mass, ionic charge and affinity. It is an important subject of Biochemistry. This work reports the development and the validation of a software that simulated a laboratory activity named Ascendant Chromatography on Paper of Aminoacids. The organization and the multimedia material collection were done during the 2008/2 semester. The most representative images were inserted into the learning object. The tool used for the software development was Adobe® Flash® CS3. The first application of this object was in Biochemistry I (Pharmacy-UFRGS in 2009/1. Using this experience, a new version was developed which was tested by the students of the same subject in 2009/2. After a 50-minute class (theoretical-practical, the students of both semesters were divided in two groups. Group I answered a questionnaire about chromatography basic concepts and after used the software. Group II was submitted to an inverse protocol. The groups also evaluated the technical aspects of the software animation/simulation and the activity carried out. Associating both applications results (2009/1 and 2009/2, the present learning object can be valid as a support for practical teaching of basic biochemistry.

  4. Paper-PEG-based membranes for hydrophobic interaction chromatography: purification of monoclonal antibody. (United States)

    Yu, Deqiang; Chen, Xiaonong; Pelton, Robert; Ghosh, Raja


    This article discusses the preparation of novel Paper-PEG interpenetrating polymer network-based membranes as inexpensive alternative to currently available adsorptive membranes. The Paper-PEG membranes were developed for carrying out hydrophobic interaction membrane chromatography (HIMC). PEG is normally very hydrophilic but can undergo phase separation and become hydrophobic in the presence of high antichaotropic salt concentrations. Two variants of the Paper-PEG membranes, Paper-PEG 1 and Paper-PEG 2 were prepared by grafting different amounts of the polymer on filter paper and these were tested for their hydraulic properties and antibody binding capacity. The better of the two membranes (Paper-PEG 1) was then used for purifying the monoclonal antibody hIgG1-CD4 from simulated mammalian cell culture supernatant. The processing conditions required for purification were systematically optimized. The dynamic antibody binding capacity of the Paper-PEG 1 membrane was about 9 mg/mL of bed volume. A single step membrane chromatographic process using Paper-PEG 1 membrane gave high monoclonal antibody purity and recovery. The hydraulic permeability of the paper-based membrane was high and was maintained even after many runs, indicating that membrane fouling was negligible and the membrane was largely incompressible.

  5. Electrochemical impedance spectroscopy in chromatography paper and its application to latex bead detection (United States)

    Iwahara, Shohei; Miki, Masashi; Hori, Fumitaka; Uno, Shigeyasu


    The principle of the quantitative immunochromatographic strip test (IST) is proposed. Electrochemical impedance spectroscopy is shown to be capable of detecting latex beads in chromatography paper, where latex beads can serve as a label in IST. Measurements to examine the impedance changes in the absence and presence of latex beads are conducted. In the presence of latex beads, an increase of 12.5% in the bulk solution resistance is observed. This indicates that the latex-bead-labeled antigen-antibody complex can be detected electrochemically by actual IST.

  6. Peak broadening in paper chromatography and related techniques VI. The efficiency of various kinds of chromatography paper and thin-layer cellulose powder for the separation of amino acids

    NARCIS (Netherlands)

    Ligny, C.L. de; Kok, E.C.M.


    The efficiency of several chromatography papers and thin-layer cellulose powders for the separation of amino acids is investigated, using the minimum elution time for a given resolution as the criterion.

  7. Evaluation of moisture penetration through skin protectant barriers by paper chromatography. (United States)

    Shah, S; Cornell, M; Ward, A J


    Currently, there is no convenient and safe experimental method in the literature to evaluate skin protectant formulations for barrier properties. A novel and simple experimental method, based on paper chromatography, was developed to screen a broad spectrum of skin protectants available for moisture penetration. The method involves the use of paper chromatography for determining the Moisture Penetration Rate through a thin barrier film of a given skin protectant product. It is simple, inexpensive, convenient, and safe and was used to evaluate 12 products currently used as skin protectants. This method can be used by formulators in their development efforts and by caregivers to determine the barrier properties of various products in a short period of time without expensive instrumentation or extensive time commitments. Skin irritation resulting from fecal and urinary incontinence is a common problem for geriatric patients (Fiers & Siebert, 1993, Talbot, 1994). Various products on the market today are used as protective barriers to prevent skin irritation from moisture penetration. However, from the caregiver's perspective, there is a need for identifying the best product or the relative ranking of products based on suitable test methods. There is a lack of suitable in vitro test methods to screen skin protectant barriers (Guillemin, Murset, Lob, & Riquez, 1974; Pigatto, Bigardi, Legori, Altomare, & Finzi, 1993) on the market. For any method to be acceptable it must be convenient, simple, reproducible, and safe for use on human volunteers. More importantly, it must have clinical relevance.

  8. Integrating Paper Chromatography with Electrochemical Detection for the Trace Analysis of TNT in Soil. (United States)

    Ryan, Patrick; Zabetakis, Daniel; Stenger, David A; Trammell, Scott A


    We report on the development of an electrochemical probe for the trace analysis of 2,4,6-trinitrotoluene (TNT) in soil samples. The probe is a combination of graphite electrodes, filter paper, with ethylene glycol and choline chloride as the solvent/electrolyte. Square wave chromatovoltammograms show the probes have a sensitivity for TNT of 0.75 nA/ng and a limit of detection of 100 ng. In addition, by taking advantage of the inherent paper chromatography step, TNT can be separated in both time and cathodic peak potential from 4-amino-dinitrotolene co-spotted on the probe or in soil samples with the presence of methyl parathion as a possible interferent.

  9. Rapid determination of moisture content in paper materials by multiple headspace extraction gas chromatography. (United States)

    Xie, Wei-Qi; Chai, Xin-Sheng


    This paper describes a new method for the rapid determination of the moisture content in paper materials. The method is based on multiple headspace extraction gas chromatography (MHE-GC) at a temperature above the boiling point of water, from which an integrated water loss from the tested sample due to evaporation can be measured and from which the moisture content in the sample can be determined. The results show that the new method has a good precision (with the relative standard deviation <0.96%), high sensitivity (the limit of quantitation=0.005%) and good accuracy (the relative differences <1.4%). Therefore, the method is quite suitable for many uses in research and industrial applications.

  10. Integrating Paper Chromatography with Electrochemical Detection for the Trace Analysis of TNT in Soil

    Directory of Open Access Journals (Sweden)

    Patrick Ryan


    Full Text Available We report on the development of an electrochemical probe for the trace analysis of 2,4,6-trinitrotoluene (TNT in soil samples. The probe is a combination of graphite electrodes, filter paper, with ethylene glycol and choline chloride as the solvent/electrolyte. Square wave chromatovoltammograms show the probes have a sensitivity for TNT of 0.75 nA/ng and a limit of detection of 100 ng. In addition, by taking advantage of the inherent paper chromatography step, TNT can be separated in both time and cathodic peak potential from 4-amino-dinitrotolene co-spotted on the probe or in soil samples with the presence of methyl parathion as a possible interferent.

  11. Evaluation of vermicompost maturity using scanning electron microscopy and paper chromatography analysis. (United States)

    Senthil Kumar, D; Satheesh Kumar, P; Rajendran, N M; Uthaya Kumar, V; Anbuganapathi, G


    Vermicompost was produced from flower waste inoculated with biofertilizers using the earthworm Eisenia fetida. Principal component analysis (PCA) and cluster analysis (CA) were carried out on the basis of physicochemical parameters of vermicomposted samples. From the results of the PCA and CA, it was possible to classify two different groups of vermicompost samples in the following categories: E2 and E5; and E1, E3, E4, and control. Scanning electron microscopy and biodynamic circular paper chromatography analysis were used to investigate the changes in surface morphology and functional groups in the control and vermicompost products. SEM analysis of E1-E5 shows more fragment and pores than the control. Chromatographic analysis of vermicompost indicated the mature condition of the compost materials.

  12. Coupling shell-isolated nanoparticle enhanced Raman spectroscopy with paper chromatography for multi-components on-site analysis. (United States)

    Zhang, Kun; Qing, Jiang; Gao, Han; Ji, Ji; Liu, Baohong


    By coupling shell-isolated nanoparticle-enhanced Raman spectroscopy (SHINERS) with paper chromatography, two birds with one stone method were developed for simultaneous on-site separation and optical detection of multiple components. The established method features high sensitivity of plasmon-enhanced sensing strategies and sufficient temporal and spatial resolution of planar chromatographic techniques.

  13. Papers

    DEFF Research Database (Denmark)

    Thoft-Christensen, Palle

    The chapters in this Volume 7 of a series of PAPERS are based on papers published in the period 2004 - 2008 authored/co-authored by Palle Thoft-Christensen......The chapters in this Volume 7 of a series of PAPERS are based on papers published in the period 2004 - 2008 authored/co-authored by Palle Thoft-Christensen...

  14. Identification des hydrocarbures polyaromatiques par chromatographie sur papier et spectrofluométrie Identifying Polyaromatic Hydrocarbons by Paper Chromatography and Spectrofluorimetry

    Directory of Open Access Journals (Sweden)

    Castex H.


    Full Text Available L'utilisation de la spectrofluorimétrie comme méthode d'analyse des hydrocarbures polynucléaires a été envisagée sur une fraction polyaromatique d'extraits de vase marine. Cette technique nécessite un fractionnement préalable par chromatographie sur papier. La comparaison des spectres d'excitation et de fluorescence de chaque bande de papier à un Rr déterminé avec des composés de référence permet l'identification et le calcul d'un ordre de grandeur de la quantité d'hydrocarbures polynucléaires prédominants, présents dans les fractions aromatiques et « résines » de l'extrait de vase. An experimentwas made using spectrofluorimetry as a way of analyzing polynuclear hydrocarbons in a polyaromatic fraction from marine mud extracts. This technique requires prior fractionation by paper chromatography. A comparison of the excitation and fluorescence spectra of each paper band at a specific Rr with reference compounds served ta identify and calculote an order of magnitude for the amount of predominant polynuclear hydrocarbons present in the aromatic fractions and « resins » from the mud extract.

  15. Two-dimensional paper chromatography-based fluorescent immunosensor for detecting acute myocardial infarction markers. (United States)

    Cho, Jung-Hwan; Kim, Min-Ha; Mok, Rak-Sun; Jeon, Jin-Woo; Lim, Guei-Sam; Chai, Chan-Young; Paek, Se-Hwan


    A novel washing scheme following antigen-antibody reactions with analyte was used during construction of a fluorescent immunosensor to resolve the background problem in the lateral flow assay with human serum. An immuno-membrane strip was devised to simultaneously measure cardiac troponin I (cTnI), creatinine kinase-MB isoform (CK-MB), and myoglobin to diagnose acute myocardial infarction. This strip was then installed within a cartridge containing a built-in washing solution tank, which was used to supply the solution across the signal generation pad of the strip after the immune reactions. Such cross-flow washing was initiated by onset-signaling from the internal control and began to run automatically upon sample addition. Under optimal conditions, the immunosensor displayed a stably suppressed background baseline, enabling us to attain a low detection limit for cTnI (0.05 ng/mL) as well as favorable reproducibility for repetitive measurements (relative standard deviation 0.98. This result suggests that the new immunosensor system based on two-dimensional chromatography can be used for clinical testing.

  16. Solid-phase microcolumn extraction and gas chromatography-mass spectrometry identification of volatile organic compounds emitted by paper. (United States)

    Hrivnák, Ján; Tölgyessy, Peter; Figedyová, Sona; Katuscák, Svetozár


    A rapid non-destructive sampling technique for the analysis of volatile organic compounds (VOCs) emitted by paper sheets is described. A capillary, which is connected to a microcolumn packed with Tenax TA, is inserted between two sheets at the centre of a paper stack encapsulated inside a PET/Al/PE composite foil. The other end of the microcolumn is connected to a gas-tight syringe and an appropriate volume of gaseous phase is aspirated. The microcolumn is then thermally desorbed in a modified GC inlet (modification is presented) and analysed by gas chromatography-mass spectrometry (GC-MS). In the chromatogram from the analysis of artificially aged paper sample 21 compounds were identified. Advantages of the method including the short sampling time (1 min), simplicity and economic aspect are discussed.

  17. Radiometric trace analysis quantitative paper chromatography of lead with phosphate-32P

    NARCIS (Netherlands)

    Erkelens, P.C. van


    A method is described for the selective determination of lead in paper chromatograms, down to 1 μg (standard deviation 11%). After development and drying, the lead spot is sprayed with a Na2H32PO4 solution and dried. Excess reagent and alkaline earth phosphates are eluted with a borax—oxalate buffer

  18. Polyethylene as a source of artifacts in the paper chromatography of chlorinated hydrocarbon insecticides (United States)

    Van Valin, C.C.; Kallman, B.J.; O'Donnell, J.J


    The introduction of artifacts from vessels, materials, and chemicals is a serious problem in the study of pesticide residues. It is therefore of interest to record findings that polyethylene wash bottles contain substances soluble in organic solvents and reactive with the silver nitrate chromogenic spray commonly employed in the paper chromatographic analysis of chlorinated organic insecticides.

  19. Size exclusion chromatography and viscometry in paper degradation studies. New Mark-Houwink coefficients for cellulose in cupri-ethylenediamine. (United States)

    Łojewski, Tomasz; Zieba, Katarzyna; Lojewska, Joanna


    The paper deals with the application of size exclusion chromatography (SEC) for the studies of paper degradation phenomena. The goal is to solve some of the technical problems connected with the calibration of multi-detector SEC system and to find the correlation between SEC and viscometric results of degree of polymerization of cellulose. The results gathered for the paper samples degraded by acidic air pollutant (NO(2)) are used as an example of SEC-MALLS application. From the correlation between intrinsic viscosities and absolute value of molecular masses obtained with SEC/MALLS (Multi Angle Laser Light Scattering) technique, Mark-Houwink coefficients for cellulose in cupri-ethylenediamine solution were determined. Thus obtained coefficients were used for the determination of viscometric degree of polymerization (molecular mass) of the aged samples. An excellent correlation was found between the chromatographic values of molecular masses obtained with SEC-UV/VIS detection and the viscometric ones utilizing the improved values of Mark-Houwink coefficients.

  20. Determination of phthalates released from paper packaging materials by solid-phase extraction-high-performance liquid chromatography. (United States)

    Gao, Xin; Yang, Bofeng; Tang, Zhixu; Luo, Xin; Wang, Fengmei; Xu, Hui; Cai, Xue


    A solid phase extraction (SPE) high-performance liquid chromatography (HPLC) method was developed for the simultaneous determination of 10 phthalic acid esters (dimethyl phthalate, diethyl phthalate, dipropyl phthalate, benzylbutyl phthalate, diisobutyl phthalate, dicyclohexyl phthalate, diamyl phthalate, di-n-hexyl phthalate, di-n-octyl phthalate and di-2-ethylhexyl phthalate) released from food paper packaging materials. The use of distilled water, 3% acetic acid (w/v), 10% ethanol (v/v) and 95% ethanol (v/v) instead of the different types of food simulated the migration of 10 phthalic acid esters from food paper packaging materials; the phthalic acid esters in four food simulants were enriched and purified by a C18 SPE column and nitrogen blowing, and quantified by HPLC with a diode array detector. The chromatographic conditions and extraction conditions were optimized and all 10 of the phthalate acid esters had a maximum absorbance at 224 nm. The method showed limitations of detection in the range of 6.0-23.8 ng/mL the correlation coefficients were greater than 0.9999 in all cases, recovery values ranged between 71.27 and 106.97% at spiking levels of 30, 60 and 90 ng/mL and relative standard deviation values ranged from 0.86 to 8.00%. The method was considered to be simple, fast and reliable for a study on the migration of these 10 phthalic acid esters from food paper packaging materials into food.

  1. Applying Chromatography. (United States)

    Klein, Jessie W.; Patev, Paul


    Presents three experiments to introduce students to different kinds of chromatography: (1) paper chromatography; (2) gel filtration chromatography; and (3) reverse-phase liquid chromatography. Written in the form of a laboratory manual, explanations of each of the techniques, materials needed, procedures, and a glossary are included. (PVD)

  2. Evaluation of hemoglobin A1c measurement from filter paper using high-performance liquid chromatography and immunoturbidimetric assay. (United States)

    Wu, Yonghua; Yang, Xu; Wang, Haining; Li, Zhenrong; Wang, Tiancheng


    Glycated hemoglobin (HbA1c) measurement from whole blood (WB) samples is inconvenient for epidemic surveillance and self-monitoring of glycemic level. We evaluated HbA1c measurement from WB blotted on filter paper (FP), which can be easily transported to central laboratories, with high-performance liquid chromatography (HPLC) and immunoturbidimetric assay (ITA). WB was applied to Whatman filter paper. By using HPLC and WB samples as reference methods, these FP samples were evaluated on HPLC and ITA. Inter- and intra-assay variation, WB vs. FP agreement and sample stability at 20-25 °C and -70 °C were assessed by statistical analysis. Results showed that the coefficient of variation (CV, %) of FP samples for HPLC and ITA were 0.44-1.02% and 1.47-2.72%, respectively (intra-assay); 2.13-3.56% and 3.21-4.82%, respectively (inter-assay). The correlation of WB HPLC with FP analyzed using HPLC and ITA are both significant (p < 0.001). Sample stability showed that FP method up to 5 days at 20-25 °C and 5 weeks at -70 °C is accurate and reproducible. In conclusion, FP samples analyzed by HPLC and ITA can both provide an alternative to WB for HbA1c measurement, supporting the use of FP method in epidemic surveillance and healthcare units.

  3. Determination of Fluorescent Whitening Agents in Paper Materials by Ion-Pair Reversed-Phase High-Performance Liquid Chromatography

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Jeong Soo; Kim, Keon [Korea Univ., Seoul (Korea, Republic of); Kim, Do Hwan [Daegu Univ., Gyeongsan (Korea, Republic of)


    A simple method was developed for the analysis of seven stilbene-type fluorescent whitening agents (FWAs) in paper materials by ion-pair reversed-phase high-performance liquid chromatography with fluorescence detection. These stilbene-type FWAs included two disulfonate, two tetrasulfonate, and three hexasulfonate compounds. After optimization of chromatographic conditions, the FWAs were satisfactorily separated using a reversed-phase column (RP-18) with the following isocratic mobile phase: methanol-water (60:40) containing 17.5 mM TBABr and 10 mM citrate buffer (pH = 7.0). The calibration plot was linear in the range from 5 to 500 ng/mL for two disulfo-FWAs and from 1 to 500 ng/mL for the other five FWAs. Precision levels of the calibration curve as indicated by RSD of response factors were 1.2 and 8.1%. Limits of quantitation (LOQ) ranged from 1.2 to 11 ng/mL.

  4. Measurement of polychlorinated biphenyls in solid waste such as transformer insulation paper by supercritical fluid extraction and gas chromatography electron capture detection. (United States)

    Chikushi, Hiroaki; Fujii, Yuka; Toda, Kei


    In this work, a method for measuring polychlorinated biphenyls (PCBs) in contaminated solid waste was investigated. This waste includes paper that is used in electric transformers to insulate electric components. The PCBs in paper sample were extracted by supercritical fluid extraction and analyzed by gas chromatography-electron capture detection. The recoveries with this method (84-101%) were much higher than those with conventional water extraction (0.08-14%), and were comparable to those with conventional organic solvent extraction. Limit of detection was 0.0074 mg kg(-1) and measurable up to 2.5 mg kg(-1) for 0.5 g of paper sample. Data for real insulation paper by the proposed method agreed well with those by the conventional organic solvent extraction. Extraction from wood and concrete was also investigated and good performance was obtained as well as for paper samples. The supercritical fluid extraction is simpler, faster, and greener than conventional organic solvent extraction.

  5. Prenatal diagnosis of methylmalonic aciduria by measuring methylmalonic acid in dried amniotic fluid on filter paper using gas chromatography-mass spectrometry. (United States)

    Inoue, Yoshito; Ohse, Morimasa


    Methylmalonic aciduria is a common inherited metabolic disorder. Methylmalonic acid (MMA), a key indicator of methylmalonic aciduria, increases in the amniotic fluid of affected fetuses. For prenatal diagnosis, the MMA in amniotic fluid can be measured by stable-isotope dilution gas chromatography-mass spectrometry. Here, we quantified the MMA in cell-free amniotic fluid samples that had been dried on filter paper and transported at ambient temperatures, and compared the results with data obtained from the original amniotic fluid. Our results indicated that the filter paper method was reproducible and accurate enough to be applied to clinical analysis. We also used the filter paper method to screen at-risk fetuses and obtained a clear diagnosis in each case. We conclude that our method enables the prenatal diagnosis of methylmalonic aciduria using practical procedures and a simplified method for transporting the samples.

  6. On the concentration and separation of the trace-elements fe, cu, zn, mn, pb, mo and co : Paper chromatography

    NARCIS (Netherlands)

    Erkelens, P.C. van


    Paper chromatographic separations are described by which the minor constituents of biological ashes are separated either into: (Pb) - Mn - Co - (Pb) - Cu - Fe, Mo, Zn; or into: Cu, Mn, Co - Pb - Fe - Mo - Zn.

  7. Coupling frontal elution paper chromatography with desorption corona beam ionization mass spectrometry for rapid analysis of chlorphenamine in herbal medicines and dietary supplements. (United States)

    Huang, Yun-Qing; You, Jing-Qing; Zhang, Junsheng; Sun, Wenjian; Ding, Li; Feng, Yu-Qi


    We developed a convenient method by coupling frontal elution paper chromatography with desorption corona beam ionization mass spectrometry (DCBI-MS) for rapid determination of chlorphenamine added in herbal medicines or dietary supplements. In this method, the ethanol extract of the herbal products was spotted directly onto an isosceles triangular filter paper sheet, and then the paper sheet was developed under strong elution condition with the sample zone migrating at the solvent front. The analyte was finally condensed at the V-shaped tip which could then be placed under the visible plasma beam of DCBI for ionization. The overall procedure took less than 5 min. The frontal elution paper chromatography on a triangular plate used in this work improved the signal intensity of chlorphenamine by 30-fold due to the analyte condensing at the tip and the reduction of the background suppression. Furthermore, the paper sheet also functioned as a filter in the analysis of solid or powder samples, which can increase the analytical throughput by omitting the step of centrifugation. The proposed method in current study was successfully applied in the determination of chlorphenamine in herbal medicines. Chlorphenamine was detected in four of the twelve types of herbal medicines examined in this study. The limit of detection was 200 ng/mL (2.0 ng absolute) in full-scan positive-ion mode and the linear range was from 5.0 μg/mL to 50 μg/mL with satisfactory linear coefficient (R(2) (the square of the correlation coefficient)=0.895). Good reproducibility was achieved with relative standard deviations (RSDs) less than 15.0% and the recoveries of chlorphenamine ranged from 84.3 to 90.6%.

  8. Environmentally friendly method for the determination of acrylamide and trimethylolpropane in paper packaging materials by liquid chromatography with tandem mass spectrometry. (United States)

    Yang, Fei; Li, Zhonghao; Bian, Zhaoyang; Tang, Gangling; Fan, Ziyan; Wang, Ying; Liu, ShanShan; Zhang, Hongfei


    A simple, rapid, and environmentally friendly method was developed for the determination of acrylamide and trimethylolpropane in paper packaging materials. No organic solvent was used and the matrix effect was investigated. The extract was directly analyzed by liquid chromatography with tandem mass chromatography for quantification and confirmation. The chromatographic separations were performed on a ZORBAX HILIC Plus (2.1 mm × 150 mm, 3μm; Agilent, USA) column with only one mobile phase (100% water). Calibration curves for acrylamide and trimethylopropane were achieved with concentrations ranging from 0.4 to 20 mg/kg and the corresponding r(2) values were 0.998 and 0.999, respectively. The recoveries were >85% with relative standard deviations paper packages. The concentrations of acrylamide and trimethylolpropane ranged from 0.41 to 7.5 and 0.50 to 8.8 mg/kg, respectively. The results of this study revealed that this method could be used accurately and precisely.

  9. Determination of nonylphenol and octylphenol in paper by microwave-assisted extraction coupled to headspace solid-phase microextraction and gas chromatography-mass spectrometry. (United States)

    Latorre, A; Lacorte, S; Barceló, D; Montury, M


    A novel and simple method for the determination of active endocrine disrupter compounds (octylphenol OP, and nonylphenol NP) in paper using microwave-assisted extraction (MAE) and headspace solid-phase microextraction, coupled with gas chromatography-mass spectrometry has been developed. Parameters affecting the efficiency in the MAE process such as exposure time and extraction solvent were studied in order to determine operating conditions. The optimised method was linear over the range studied (1.25-125 microg kg(-1) for OP and 9.50-950 microg kg(-1) for NP) and showed good level of precision, with a RSD lower than 10% and detection limits at 0.10 and 4.56 microg kg(-1) for OP and NP, respectively. The results obtained from six different types of paper revealed the presence of the target compounds in all samples analysed, at levels ranging between 3 and 211 microg kg(-1).

  10. Detection of deoxyribonucleic acid (DNA) targets using polymerase chain reaction (PCR) and paper surface-enhanced Raman spectroscopy (SERS) chromatography. (United States)

    Hoppmann, Eric P; Yu, Wei W; White, Ian M


    Surface-enhanced Raman spectroscopy (SERS) enables multiplex detection of analytes using simple, portable equipment consisting of a single excitation source and detector. Thus, in theory, SERS is ideally suited to replace fluorescence in assays that screen for numerous deoxyribonucleic acid (DNA) targets, but in practice, SERS-based assays have suffered from complexity and elaborate processing steps. Here, we report an assay in which a simple inkjet-fabricated plasmonic paper device enables SERS-based detection of multiple DNA targets within a single polymerase chain reaction (PCR). In prior work, we demonstrated the principles of chromatographic separation and SERS-based detection on inkjet-fabricated plasmonic paper. The present work extends that capability for post-PCR gene sequence detection. In this design, hydrolysis DNA probes with 5' Raman labels are utilized; if the target is present, the probe is hydrolyzed during PCR, freeing the reporter. After applying the PCR sample to a paper SERS device, an on-device chromatographic separation and concentration is conducted to discriminate between hydrolyzed and intact probes. SERS is then used to detect the reporter released by the hydrolyzed probes. This simple separation and detection on paper eliminates the need for complex sample processing steps. In this work, we simultaneously detect the methicillin-resistant Staphylococcus aureus genes mecA and femB to illustrate the concept. We envision that this approach could contribute to the development of multiplex DNA diagnostic tests enabling screening for several target sequences within a single reaction, which is necessary for cases in which sample volume and resources are limited.

  11. Application of paper chromatography to the determination of some elements in minerals and rocks; Application de la chromatographie sur papier a la determination de certains elements dans les mineraux et les roches

    Energy Technology Data Exchange (ETDEWEB)

    Agrinier, H. [Commissariat a l' Energie Atomique, Fontenay-aux-Roses (France). Centre d' Etudes Nucleaires


    This publication describes our work in applying paper chromatography to the fields of mineralogy and geology. We have studied the separation and determination of the following elements: Nb, Ta, Ti, Co, Cu, Mn, Sn, Ge, As, Sb, Bi, U, Th, Be, Au, Pb, Zn, V and Mo. The development of separation methods for these various elements has led us to solve many interference problems. These methods make it possible to separate and measure mineral components. They also enable us to search for trace elements in ores, rocks soils and carbonaceous materials. Finally let us point out that this technique may equally be used for analysis in very radioactive environment. (author) [French] Dans cette etude, nous etendons le champ d'application de la chromatographie sur papier aux domaines de la mineralogie et de la geologie. Nous avons etudie la separation et la determination des elements suivants: Nb, Ta, Ti, Co, Cu, Mn, Sn, Ge, As, Sb, Bi, U, Th, Be, Au, Pb, Zn, V et Mo. La mise au point des methodes de separation concernant ces differents elements nous a amenes a resoudre de nombreux problemes d'interference. Ces methodes permettent la separation et le dosage des constituants des mineraux, ainsi que la recherche d'elements en traces dans les minerais, les roches, les sols et les materiaux carbonnes. Signalons pour terminer que cette technique peut egalement trouver son utilisation dans le domaine de l'analyse en milieu tres radio-actif. (auteur)

  12. Analysis of isothiazolinone biocides in paper for food packaging by ultra-high-performance liquid chromatography-tandem mass spectrometry. (United States)

    Lin, Q-B; Wang, T-J; Song, H; Li, B


    A novel and simple method to detect isothiazolinone-type biocides (2-methyl-3-isothiazolinone (MI), 5-chloro-2-methyl-3-isothiazolinone (CMI), 1,2-benzisothiazolinone (BIT) and 2-octyl-3-isothiazolinone (OIT)) in paper used for food packaging by ultrasonic extraction coupled with UPLC-MS/MS was developed. Parameters affecting process efficiency such as extraction solvents, UPLC mobile phase, gradient elution procedure and MS/MS conditions were studied to optimise the operating conditions. Using the optimised gradient elution procedure, the retention time was less than 6 min. The limits of detection (LODs) were found to be between 0.001 and 0.010 mg kg⁻¹, which was validated using actual concentrations. After diluting the standard solution with a blank matrix, the linear calibration curve ranges were 0.002-1.000 mg kg⁻¹ for BIT and OIT, 0.005-1.000 mg kg⁻¹ for MI, and 0.020-1.000 mg kg⁻¹ for CMI, with correlation coefficients higher than 0.9985 (n = 6). A good level of precision with a mean recovery greater than 81.3% and a relative standard deviation (RSD) less than 6.2% were also obtained. A methodology has been proposed for the analysis of isothiazolinones in paper.

  13. A simple analytical platform based on thin-layer chromatography coupled with paper-based analytical device for determination of total capsaicinoids in chilli samples. (United States)

    Dawan, Phanphruk; Satarpai, Thiphol; Tuchinda, Patoomratana; Shiowatana, Juwadee; Siripinyanond, Atitaya


    A new analytical platform based on the use of thin-layer chromatography (TLC) coupled with paper-based analytical device (PAD) was developed for the determination of total capsaicinoids in chilli samples. This newly developed TLC-PAD is simple and low-cost without any requirement of special instrument or skillful person. The analysis consisted of two steps, i.e., extraction of capsaicinoids from chilli samples by using ethanol as solvent and separation of capsaicinoids by thin-layer chromatography (TLC) and elution of capsaicinoids from the TLC plate with in situ colorimetric detection of capsaicinoids on the PAD. For colorimetric detection, Folin-Ciocalteu reagent was used to detect phenolic functional group of capsaicinoids yielding the blue color. The blue color on the PAD was imaged by a scanner followed by evaluation of its grayscale intensity value by ImageJ program. This newly developed TLC-PAD method provided a linear range from 50 to 1000mgL(-1) capsaicinoids with the limit of detection as low as 50mgL(-1) capsaicinoids. The proposed method was applied to determine capsaicinoids in dried chilli and seasoning powder samples and the results were in good agreement with those obtained by HPLC method.

  14. Straightforward and rapid determination of sulfadoxine and sulfamethoxazole in capillary blood on sampling paper with liquid chromatography and UV detection. (United States)

    Lindkvist, J; Malm, M; Bergqvist, Y


    A method for the determination of sulfadoxine and sulfamethoxazole in capillary blood on sampling paper has been developed and validated. The method is straightforward with minimal sample preparation, and is suitable for rural settings. Separation of sulfadoxine, sulfamethoxazole and internal standard was performed using a Purospher STAR RP-18 endcapped LC column (150x4.6mm) with a mobile phase consisting of acetonitrile:sodium acetate buffer pH 5.2, I=0.1 (1:2, v/v). For sulfadoxine, the within-day precision was 5.3% at 15micromol/l and 3.7% at 600micromol/l, while for sulfamethoxazole it was 5.7% at 15micromol/l and 3.8% at 600micromol/l. The lower limit of quantification was determined to 5micromol/l and precision was 5.5% and 5.0% for sulfadoxine and sulfamethoxazole, respectively.

  15. Simultaneous determination of 11 fluorescent whitening agents in food-contact paper and board by ion-pairing high-performance liquid chromatography with fluorescence detection. (United States)

    Jiang, Dingguo; Chen, Lisong; Fu, Wusheng; Qiu, Hanquan


    4,4'-Diaminostilbene-2,2'-disulfonic acid based fluorescent whitening agents (DSD-FWAs) are prohibited in food-contact paper and board in many countries. In this work, a reliable high-performance liquid chromatography method was developed for the simultaneous determination of 11 common DSD-FWAs in paper material. Sample preparation and extraction as well as chromatographic separation of multicomponent DSD-FWAs were successfully optimized. DSD-FWAs in prepared samples were ultrasonically extracted with acetonitrile/water/triethylamine (40:60:1, v/v/v), separated on the C(18) column with the mobile phase containing tetrabutylammonium bromide, and then detected by a fluorescence detector. The limits of detection were 0.12-0.24 mg/kg, and the calibration curves showed the linear correlation (R(2) ≥ 0.9994) within the range of 8.0-100 ng/mL, which was equivalent to the range of 0.80-10 mg/kg in the sample. The average recoveries and the RSDs were 81-106% and 2-9% at two fortification levels (1.0 and 5.0 mg/kg) in paper bowls, respectively. The successful determination of 11 DSD-FWAs in food-contact paper and board obtained from local markets indicated that the newly developed method was rapid, accurate, and highly selective.

  16. A method for the low-level (ng g(-1)) determination of perfluorooctanoate in paper and textile by liquid chromatography with tandem mass spectrometry. (United States)

    Stadalius, Marilyn; Connolly, Paul; L'Empereur, Karen; Flaherty, John M; Isemura, Tsuguhide; Kaiser, Mary A; Knaup, Wolfgang; Noguchi, Masahiro


    The determination of perfluorooctanoate (PFO) in articles of commerce has become increasingly important to understand if treated products are a possible source of PFO. An LC-MS/MS method for the determination of PFO in paper and textile using a dual labeled 13C-PFOA internal standard was successfully developed and validated. Residues of PFO were determined using an isocratic, reversed-phase high-performance liquid chromatography (HPLC) method with an ammonium acetate/methanol buffer. Ions monitored were 413 (parent) and 369 (daughter) for PFO and 415 (parent) and 370 (daughter) for dual labeled 13C-PFOA internal standard. As a precaution against ubiquitous PFO that occasionally occurs in mobile phase or instrument components, two Hypercarb cartridges (4 mm) were placed before the HPLC injector. Any PFO that was captured by the cartridges was removed before each injection by flushing the system with 100% methanol prior to equilibration with the isocratic mobile phase. Overall recovery and standard deviation over a 3 day validation regimen for samples (n=54-55) fortified with PFOA at 5, 50, and 200 ng g(-1) were 114+/-4.9% for textile and 110+/-7.6% for paper. The results also established a limit of detection (LOD) of 1 ng g(-1) in textile and 2 ng g(-1) in paper based upon S/N of the 5.0 ng g(-1) fortification versus the untreated paper and textile.

  17. 纸层析-分光光度法检测茶氨酸%Determination of Theanine in Tea (Camellia sinensis L.) by Paper Chromatography-Spectrophotometry

    Institute of Scientific and Technical Information of China (English)

    马雪泷; 邹鹏飞; 王荡强; 曹顺利; 房江育; 王昶


    为了满足普通实验室对茶中茶氨酸测定的需要,研究了茶氨酸的纸层析-分光光度检测方法.结果表明,用茚三酮-乙醇水溶液做展层剂,对茶苗根.芽叶和茶叶的水浸提液进行纸层析,能够有效地将茶氨酸与其它氨基酸分离,紫色色斑清晰而均匀.用乙醇溶液洗脱色斑后用分光光度计在570 nm比色,在20~70 μL茶氨酸溶液点样量范围内其含量与吸光度呈线性关系.本方法检出限为0.0057 mg·mL-1,测定下限为0.0191 mg·mL-1,平均回收率90.28%~115.38%,平均相对标准差1.51%,具有安全、药品种类少和操作步骤简单等特点.%To meet the needs of ordinary laboratory determination of theanine, paper chromatographic-spectrophotometry was developed. The results showed that by paper chromatography, ninhydrin-ethanol water solution could effectively separate theanine from other amino acids extracted in the water from roots or shoots of tea seedling or from tea. The purple stains were clear and even. After the stains were eluted with ethanol solution, theanine content could be assayed with the spectrophotometer at 570 nm. The theanine content appeared a linera relationship with the absorption value when the solution was sported on the paper at the range of 20-70 uL. The detection limit was 0.0057 mg-mL"' and the lowest detection limit was 0.0191 mg-mL'1. The average recovery ranged from 90.28% to 115.38%, and the average relative standard deviation was 1.51%. The paper chromatography-spectrophotometry characterizes safety, fewer chemicals, and easy to operate.

  18. 气相色谱法检验常见复印纸的研究%The Study of Analysis Extraction of Copy Papers by Gas Chromatography

    Institute of Scientific and Technical Information of China (English)



    Methanol extraction of copy papers collected from different manufacturing plant and different brand in market was analysised by gas chromatography.The samples were identified according to the number,retetion time and height value of chromatogram peak,then the reappearing of the method was examined.The results of test were obviously and operated easily.A useful method of identified methanol extraction of copy papers was provided for forensic analysis.%建立了利用气相色谱仪对不同厂家不同牌号的复印纸甲醇提取物进行了检验研究。根据色谱峰的个数、保留时间和峰高比例的不同对复印纸的种类进行了鉴别,并考查了方法的重现性,结果表明利用甲醇提取物鉴别复印纸的方法,重现性好,所需样品量少,操作简便,结果准确可靠,适用于法庭科学中涉案纸张的鉴别。

  19. Ionic liquid as a mobile phase additive in high-performance liquid chromatography for the simultaneous determination of eleven fluorescent whitening agents in paper materials. (United States)

    Wang, Qing; Chen, Xianbo; Qiu, Bin; Zhou, Liang; Zhang, Hui; Xie, Juan; Luo, Yan; Wang, Bin


    In the present study, 11 4,4'-diaminostilbene-2,2'-disulfonic acid based fluorescent whitening agents with different numbers of sulfonic acid groups were separated by using an ionic liquid as a mobile phase additive in high-performance liquid chromatography with fluorescence detection. The effects of ionic liquid concentration, pH of mobile phase B, and composition of mobile phase A on the separation of fluorescent whitening agents were systematically investigated. The ionic liquid tetrabutylammonium tetrafluoroborate is superior to tetrabutylammomnium bromide for the separation of the fluorescent whitening agents. The optimal separation conditions were an ionic liquid concentration at 8 mM and the pH of mobile phase B at 8.5 with methanol as mobile phase A. The established method exhibited low limits of detection (0.04-0.07 ng/mL) and wide linearity ranges (0.30-20 ng/mL) with high linear correlation coefficients from 0.9994 to 0.9998. The optimized procedure was applied to analyze target analytes in paper samples with satisfactory results. Eleven target analytes were quantified, and the recoveries of spiked paper samples were in the range of 85-105% with the relative standard deviations from 2.1 to 5.1%. The obtained results indicated that the method was efficient for detection of 11 fluorescent whitening agents.

  20. Determination of L-valine by improved quantitative paper chromatography%纸层析法测定缬氨酸含量的改良

    Institute of Scientific and Technical Information of China (English)

    莫少文; 姚城镇; 张云开; 陈桂光; 梁智群


    改进了缬氨酸含量的测定方法。探讨了茚三酮与缬氨酸完全反应的质量分数范围;将传统的静置洗脱更改为匀速摇床洗脱,使洗脱更完全;在此基础上,详细研究了操作过程中的相关参数,使结果更精确。结果表明,该方法有很高的准确度和精密度,操作简便,成本低,可以广泛应用于茚三酮反应测定氨基酸。%An improved quantitative paper chromatography of L-valine was reported. The range of valine concentration to certain ninhydrin was discussed,shaker was used in decolorization to enhance the elution.What' s more,the related parameters of the operational process was researched in detail.The results showed that this method could be used to determine amino acids extensively, for its high accuracy and precision, and it was simpler and cheaper than HLPC.

  1. Study of cis- and trans-uranium elements by paper chromatography and electrophoresis; Contribution a l'etude des elements cis- et trans-uraniens par chromatographie sur papier et electrophorese

    Energy Technology Data Exchange (ETDEWEB)

    Clanet, F. [Commissariat a l' Energie Atomique, 92 - Fontenay-aux-Roses (France). Centre d' Etudes Nucleaires


    In this work, the field of application of paper chromatography and electrophoresis in inorganic chemistry has been extended to elements 90 to 96 in hydrochloric and nitric acid solution. Results obtained concern the following points: 1) - Characterization of the valency states of Np and of Pu using coloured reactions on chromatograms and electrophoregrams. The valency IV is characterized by alizarin, arsenazo-I and thorin-I, whilst diphenylcarbazide is used for the hexavalent state. 2) - Paper chromatography: by using as eluent, mixtures of equal parts of aqueous HCl and HNO{sub 3} solutions and of alcohols (methanol, ethanol and n-butanol), the R{sub f} values of elements 90 to 96 have been determined. It has been possible to deduce certain conclusions concerning the complexing of these elements by Cl{sup -} and NO{sub 3}{sup -} ions. 3) - We have developed an electrophoretic technique on cellulose acetate membranes in order to separate the charged species formed by the elements 90 to 96 in HCl and HNO{sub 3} solutions from 1 to 12 M. Mobility curves have been obtained. It appears from our results that the tendency for the elements considered to form anionic complexes follows the order of the ionic potentials when the valency state is four; this order is reversed for the valency three. The ions Cl{sup -} have a smaller tendency to form complexes than the NO{sub 3}{sup -} ions with respect to these elements in their oxidation state III or IV, but the reverse phenomenon is observed for U{sup VI} and Pu{sup VI}. Finally, the complexing of the cations Pu{sup 4+} and PuUO{sub 2}{sup 2+} by NO{sub 3}{sup -} follows the order of the ionic potentials but occurs in the reverse order for Cl{sup -} ions. 4) - Various analytical applications are considered: separation of the various elements from each other and separation of the valency states of Np and of Pu. (author) [French] Dans cette etude, le champ d'application de la chromatographie sur papier et de l

  2. 单增李斯特菌磁性试纸条层析体系的研究%Magnetic Test Paper Chromatography System for Listeria monocytogenes

    Institute of Scientific and Technical Information of China (English)

    林婷婷; 卢瑛; 潘迎捷


    将单增李斯特菌的多克隆抗体和羊抗鼠IgG(二抗)喷涂于硝酸纤维素膜(NC膜)上分别作为检测线C和质控线T.将单增李斯特菌的单克隆抗体与磁性纳米材料进行化学偶联构建磁性纳米探针,建立双抗夹心模式的检测试纸条.通过在层析体系中分别添加表面活性剂、盐离子、杂蛋白和糖类,探讨其对层析的影响,以提高检测的准确性和灵敏度.研究发现,在层析体系中添加一定浓度的Tween-20、KCl、BSA和葡聚糖,可以实现单增李斯特菌的快速检测.本文研究对今后研发类似磁性试纸条检测技术具有重要参考价值.%Anti-Ltsteria monocytogenes polyclonal antibody and goat anti-mouse IgG ( bi-antibody) were sprayed on the nitrocellulose membrane respectively as test line T and Ihe quality control line C. A double-antibody sandwich mode determination test paper was constructed by using anti-L. monocytogenes monoclonal antibody chemically coupled with magnetic nano-material as nano probe. By means of adding respective surfactants, salts ion, sundry protein, and carbohydrate to study their impact on chromatography system, in order to improve the accuracy and sensitivity of the test and determination. The study was found that certain concentration of Tween-20, KC1, BSA and dextran could realize rapid detection of L monocytogenes. This study has important reference value to research and develop the similar magnetic test paper determination technology in the coming years.

  3. Green chromatography. (United States)

    Płotka, Justyna; Tobiszewski, Marek; Sulej, Anna Maria; Kupska, Magdalena; Górecki, Tadeusz; Namieśnik, Jacek


    Analysis of organic compounds in samples characterized by different composition of the matrix is very important in many areas. A vast majority of organic compound determinations are performed using gas or liquid chromatographic methods. It is thus very important that these methods have negligible environmental impact. Chromatographic techniques have the potential to be greener at all steps of the analysis, from sample collection and preparation to separation and final determination. The paper summarizes the approaches used to accomplish the goals of green chromatography. While complete elimination of sample preparation would be an ideal approach, it is not always practical. Solventless extraction techniques offer a very good alternative. Where solvents must be used, the focus should be on the minimization of their consumption. The approaches used to make chromatographic separations greener differ depending on the type of chromatography. In gas chromatography it is advisable to move away from using helium as the carrier gas because it is a non-renewable resource. GC separations using low thermal mass technology can be greener because of energy savings offered by this technology. In liquid chromatography the focus should be on the reduction of solvent consumption and replacement of toxic and environmentally hazardous solvents with more benign alternatives. Multidimensional separation techniques have the potential to make the analysis greener in both GC and LC. The environmental impact of the method is often determined by the location of the instrument with respect to the sample collection point.

  4. Determination of vanillylmandelic acid, vanillactic acid, and homovanillic acid in dried urine on filter-paper discs by high-performance liquid chromatography with coulometric electrochemical detection for neuroblastoma screening. (United States)

    Kinoshita, Y; Yamada, S; Haraguchi, K; Takayanagi, T; Mori, Y; Takahashi, T; Haruki, E


    We report a method for determination of vanillylmandelic acid, vanillactic acid, and homovanillic acid by high-performance liquid chromatography (HPLC), with coulometric electrochemical detection, for mass screening of neuroblastoma. Urine samples were collected on filter paper, dried, and then pretreated. The chromatographic procedure is reliable and fast, allowing for a large sample throughput for routine screening. Intricate extraction procedures and centrifugal separation are unnecessary. Screening for neuroblastoma by HPLC is rapidly gaining acceptance in Japan, and our method is being used at many screening centers. Of 26,571 infants screened in one year in Yokohama City, our method detected five with neuroblastoma.

  5. Paper chromatography of anthocyanins in two species of Aconitum from the Tatry .Mts.: A. variegatum (L.) Rchb., and A. napellus ssp. skerisorae (Gayer) Seitz.


    Krzakowa, M.; R. Zieliński; Szweykowski, J.


    The results of studies on phenolic compounds occurence and variation in the two Aconitum species were reported in our previous paper (Szweykowski, Krzakowa, 1977a and b). A modified extraction method allowed us to get additional data on anthocyanin variation in flowers of the same species. In addition one albino plant of A. variegatum was also investigated in this respect.

  6. Paper chromatography of anthocyanins in two species of Aconitum from the Tatry .Mts.: A. variegatum (L. Rchb., and A. napellus ssp. skerisorae (Gayer Seitz.

    Directory of Open Access Journals (Sweden)

    M. Krzakowa


    Full Text Available The results of studies on phenolic compounds occurence and variation in the two Aconitum species were reported in our previous paper (Szweykowski, Krzakowa, 1977a and b. A modified extraction method allowed us to get additional data on anthocyanin variation in flowers of the same species. In addition one albino plant of A. variegatum was also investigated in this respect.

  7. Identificação de pigmentos naturais de espécies vegetais utilizando-se cromatografia em papel Identification of natural pigments from vegetal species using paper chromatography

    Directory of Open Access Journals (Sweden)

    Fabiano Okumura


    Full Text Available The use of natural dyes to demonstrate principles of paper chromatography is proposed. Extraction of the coloring compounds were performed in order to obtain the aglycone form of the anthocyanins present in the crude extracts. Separations were carried out on chromatographic paper with BAW (butanol/acetic acid/water as mobile phase and the results compared with literature data. The crude extracts were obtained from Tibouchina granulosa, Rododhendron simsii, Impatiens walleriana flowers which are wildely found in Brazil and Phaseolus vulgaris L. grains skin which is the principal ingredient of the world famous "feijoada". Such species were chosen in order to attract the students attention since they are present in their quotidian, in agreement with the new proposals for Brazilian education.


    Institute of Scientific and Technical Information of China (English)

    YANGGengliang; TAOZuyi


    The unified theoretical moment expressions for elution chromatography and frontal chromatography when the sorption process is described by a linear model were derived. The moment expressions derived by previous authors can be obtained from these unified theoretical moment expressions. In this paper, a mathematical analysis has been carried out so as to set up a unified theoretical basis for elution and frontal chromatography.

  9. Determination of primary aromatic amines in cold water extract of coloured paper napkin samples by liquid chromatography-tandem mass spectrometry. (United States)

    Yavuz, Oguzhan; Valzacchi, Sandro; Hoekstra, Eddo; Simoneau, Catherine


    The aim of this study was the optimisation of a multi-analyte method for the analysis of primary aromatic amines (PAAs) from napkins in order to support official controls and food safety. We developed a UHPLC-MS/MS method for the simultaneous determination of 36 toxicologically relevant PAAs for paper and board. Good regression coefficients of the calibration curves in a range of 0.992-0.999 and reproducibilities in a range of 2.3-15% were obtained. Limits of detections (LODs) were in the range of 0.03-1.4 µg l(-1) and recoveries were in a range of 21-110% for all the amines. A total of 93 coloured paper napkin samples from different European countries were bought and extracted with water to determine the PAAs. The results showed that 42 of 93 samples contained at least one PAA. More than half of the detected PAAs are considered as toxic, carcinogenic or probably carcinogenic to humans by the International Agency for Research on Cancer (IARC), or are classified as such in the European Union legislation on chemicals. Summed concentrations of PAAs in seven samples were higher than 10 µg l(-1), the limit of summed PAA in the European Union plastic food contact material regulation. Also, eight PAAs, classified as Category 1A and 1B carcinogen in the European Union legislation of chemicals, were detected at concentrations higher than 2 µg l(-1), exceeding the limit proposed by the Federal Institute for Risk Assessment in Germany. Aniline (n = 14) was most frequently present in higher concentrations followed by o-toluidine, o-anisidine, 2,4-dimethylaniline and 4-aminoazobenzene. Red, orange, yellow and multicoloured paper napkins contained the highest concentrations of total PAAs (> 10 µg l(-1)). Although the European Union has not harmonised the legislation of paper and board materials and, thus, there is no specific migration limit for PAAs from paper napkins, the present study showed that coloured paper napkins can contain toxic and carcinogenic PAAs at

  10. Separation of whey proteins for chromatography liquid


    Abraham D. Giraldo Zuñiga; Edwin E.García Rojas; Jane S. R. Coimbra; Wilmer E. Luera Peña


    This paper describes and compares three chromatographic methods for the analysis and quantification of most abundant proteins in cheese whey, -lactalbumin and -lactoglobulin. The methods were: Reverse-phase high performance liquid chromatography, anion Exchange chromatography and size-exclusion chromatography. The reverse- phase liquid chromatography led to a better separation of whey proteins than size-exclusion chromatography and anion exchange chromatography, this method offered an excel...

  11. Peak capacity in unidimensional chromatography. (United States)

    Neue, Uwe Dieter


    The currently existing knowledge about peak capacity in unidimensional separations is reviewed. The majority of the paper is dedicated to reversed-phase gradient chromatography, covering specific techniques as well as the subject of peak compression. Other sections deal with peak capacity in isocratic chromatography, size-exclusion chromatography and ion-exchange chromatography. An important topic is the limitation of the separation power and the meaning of the concept of peak capacity for real applications.

  12. 纸色谱法筛选知母中α-葡萄糖苷酶抑制剂%Screening ofα-Glucosidase Inhibitors From Rhizoma Anemarrhenaes by Paper Chromatography

    Institute of Scientific and Technical Information of China (English)

    陈丽华; 潘自红; 曹云丽; 马庆一


    The enzymatic reaction method, paper chromatography and spectrophotometric method were combined to screenα-glucosidase inhibitors from Rhizoma anemarrhenaes in this experiment. The experimental conditions were as follows:the concentration of substrate was 10 mg/mL, amount of the enzyme was 100 µL,and the reaction time was 8 h in enzymatic reaction;the optimum condition of paper chromatography:volume of samp1e was 70 µL, open system was n-butyl alcohol-acetone-water(7∶2∶1), developing direction was radial direction;in spectrophotometric determination, after chromatography ,aniline phthalate was used as color developing reagent, then distilled water was used to elute, the wavelength for the absorbance reading was 365 nm.The experimental results show that aqueous extract, saponin, flavonoid and polysaccharide of rhizoma anemarrhenae, are good inhibitors of a-glucosidase,then Chinese herbal medicine rhizoma anemarrhenae is really excellent hypoglycemic plant resources.%  采用酶反应、纸色谱和比色相结合法筛选知母中α-葡萄糖苷酶抑制剂。实验条件:1)酶反应:底物浓度10 mg/mL、酶用量为100μL、反应时间8 h;2)纸色谱测定微量葡萄糖:点样量70μL、展开体系正丁醇-丙酮-水(2︰7︰1)、展开方向为径向;3)比色:色谱后苯胺-邻苯二甲酸盐显色,蒸馏水洗脱,比色波长为365 nm。实验结果表明知母水粗提物及其多糖、皂甙、黄酮组分均为α-萄糖苷酶抑制剂,而中草药知母确为优良的降糖植物资源。

  13. Neuere Chromatographie (United States)

    Hostettmann, K.


    Besides high-performance liquid chromatography (HPLC) which is now a well-established and currently used technique, several emerging methods for the isolation and separation of natural products are receiving considerable attention. Centrifugal thin-layer chromatography is a very rapid technique, but limited in resolution. Of special interest are the recently developed support-free liquid-liquid chromatography methods such as droplet counter-current chromatography (DCCC) and rotation locular counter-current chromatography (RLCC). This latter method was applied to the separation of the enantiomers of (±)-norephedrine.

  14. Hot-water and solid-phase extraction of fluorescent whitening agents in paper materials and infant clothes followed by unequivocal determination with ion-pair chromatography-tandem mass spectrometry. (United States)

    Chen, Hsin-Chang; Ding, Wang-Hsien


    A comprehensive method for the determination of four stilbene-type disulfonate and one distyrylbiphenyl-type fluorescent whitening agents (FWAs) in paper materials (napkin and paper tissue) and infant clothes was developed. FWAs were extracted from paper material and cloth samples using a hot-water extraction, and the aqueous extracts were then preconcentrated with the newly developed Oasis WAX (mixed-mode of weak anion exchange and reversed-phase sorbent) solid-phase extraction cartridge. The analytes were unequivocal determined by ion pair chromatography coupled with negative electrospray ionization-tandem mass spectrometry (HPLC-ESI-MS-MS), applying a di-n-hexyl-ammonium acetate (DHAA) as the ion-pairing reagent in mobile phase. Limits of quantitation (LOQ) were established between 0.2 and 0.9 ng/g in 2 g of samples. Recovery of five FWAs in spiked commercial samples was between 42 and 95% and RSD (n = 3) ranging from 2 to 11%. The method was finally applied to commercial samples, showing that two stilbene-type disulfonates were predominant FWAs detected in napkin and infant cloth samples.

  15. Uncertainty evaluation of citrate content in cigarette paper by ion chromatography%离子色谱法测定卷烟纸中柠檬酸根含量的不确定度分析

    Institute of Scientific and Technical Information of China (English)


      为增强测试结果的可信性,依据《C NA S-GL06化学分析中不确定度的评估指南》,评定了离子色谱仪测定卷烟纸中柠檬酸盐的不确定度。结果表明,卷烟纸中柠檬酸盐含量为2.136%,扩展不确定度为0.026%。不确定度的最大来源为仪器的重复测量,其次是药品纯度。%According to CNAS- GL06 Guidance on Evaluating the Uncertainty in Chemical Analysis, uncertainty evaluation of citrate in cigarette paper was assessed by ion chromatography so as to improve the credibility of the test result. The result shows that the concentration of citrate in cigarette paper is 2.136% and expanded uncertainty 0.026%. The main factors affecting determination uncertainty of citrate comes from the repeatability by ion chromatograph, and then the purity of chemicals.

  16. Determination of bisphenol-type endocrine disrupting compounds in food-contact recycled-paper materials by focused ultrasonic solid-liquid extraction and ultra performance liquid chromatography-high resolution mass spectrometry. (United States)

    Pérez-Palacios, David; Fernández-Recio, Miguel Ángel; Moreta, Cristina; Tena, María Teresa


    Focused ultrasonic solid-liquid extraction (FUSLE) and reverse-phase ultra performance liquid chromatography (UPLC) coupled to a quadrupole-time of flight mass spectrometer (Q-TOF-MS) was applied to the determination of bisphenol-type endocrine disrupting compounds (EDCs) in food-contact recycled-paper materials. Recycled paper is a potential source of EDCs. Bisphenol A (BPA), bisphenol F (BPF) and their derivatives bisphenol A diglycidyl ether (BADGE) and bisphenol F diglycidyl ether (BFDGE) are used for the production of epoxy resins employed in the formulation of printing inks. The FUSLE of bisphenol-type EDCs from packaging is reported for the first time. First, different extraction solvents were studied and methanol was selected. Then, the main FUSLE factors affecting the extraction efficiency (solvent volume, extraction time and ultrasonic irradiation power) were studied by means of a central composite design. The FUSLE conditions selected for further experiments were 20 ml of methanol at ultrasonic amplitude of 100% for 5s. Finally, the number of extraction cycles necessary for complete extraction was established in two. The analysis of the FUSLE extracts was carried out by UPLC-Q-TOF-MS with electrospray ionization and the determination of the four analytes took place in only 4 min. The FUSLE and UPLC-ESI-QTOF-MS method was validated and applied to the analysis of different food-contact recycled-paper-based materials and packaging. The proposed method provided recoveries from 72% to 97%, repeatability and intermediate precision under 9% and 14%, respectively, and detection limits of 0.33, 0.16, 0.65 and 0.40 μg/g for BPA, BPF, BADGE and BFDGE, respectively. The analysis of paper and cardboard samples confirmed the presence of EDCs in these packaging.

  17. Flow Rates in Liquid Chromatography, Gas Chromatography and Supercritical Fluid Chromatography: A Tool for Optimization


    Joris Meurs


    This paper aimed to develop a standalone application for optimizing flow rates in liquid chromatography (LC), gas chromatography (GC) and supercritical fluid chromatography (SFC). To do so, Van Deemter’s equation, Knox’ equation and Golay’s equation were implemented in a MATLAB script and subsequently a graphical user interface (GUI) was created. The application will show the optimal flow rate or linear velocity and the corresponding plate height for the set input parameters. Furthermore, a p...

  18. Analysis of Surrogate Contaminants in Paper-plastic Food Packaging Material by Capillary Gas Chromatography%纸塑复合食品包装材料中模拟污染物的GC检测技术

    Institute of Scientific and Technical Information of China (English)

    黄秀玲; 刘志刚; 王志伟; 许文才; 刘全校


    A GC-FID method was established for the determination of photoinitiators (PIs) in paper-plastic packaging material 4015 which solved in 95% ethanol. The pre-treatment protocol for 1 -hydroxycyclohexyl-phenyl ketone and 2 ,2-dimethoxy-2-phenylacotophenone in 95% ethanol was introduced. The influencing factors such as chromatography column, injection mode and velocity of flow of carrier gas were discussed. The results showed that the peaks of two PIs and impurity from paper were completely separated. The linearity was good (0. 999 7 and 0. 999 8) with the detection thresholds of 0. 05mg/L and 0. 1 mg/L, respectively. The RSDs were less than 5% , and the average recovery for Pis in 95% ethanol was in the range of 94% - 107% and 93% - 102% , respectively.%建立了纸塑复合包装材料4015中的模拟墨成分1-羟基环己基苯基甲酮和2,2-二甲氧基-苯基甲酮在脂肪性食品模拟物95%乙醇的气相色谱-氢火焰离子化检测器检测条件,并介绍了体积分数95%乙醇的前处理方法,讨论了色谱柱、进样方式、载气流速对测定的影响.分析结果表明:该法可将2种光引发剂和纸中杂质完全分离,具有较好的线性(相关系数分别为0.999 7和0.999 8),最低检出限分别为0.05 mg/L和0.1 mg/L,测定结果的相对标准偏差均<5.0%,样品在95%乙醇中的平均回收率分别为94%-107%和93%-102%.

  19. Gas chromatography (United States)

    Guiochon, Georges; Guillemin, Claude L.


    Gas chromatography is a powerful separation technique for gas and vapor mixtures. Combining separation and on-line detection permits accurate quantitative analysis of complex mixtures, including traces of compounds down to parts per trillions in some particular cases. The importance of gas chromatography in quality control and process control in the chemical and drug industry, in environmental pollution investigations and in clinical analysis is critical. The principles of the technique are discussed, the main components of a gas chromatograph are described and some idea of the importance of the applications is given.

  20. Ion Chromatography. (United States)

    Mulik, James D.; Sawicki, Eugene


    Accurate for the analysis of ions in solution, this form of analysis enables the analyst to directly assay many compounds that previously were difficult or impossible to analyze. The method is a combination of the methodologies of ion exchange, liquid chromatography, and conductimetric determination with eluant suppression. (Author/RE)

  1. Exploring Paper. (United States)

    Brand, Judith, Ed.


    Exploratorium Magazine communicates ideas that exhibits cannot easily demonstrate, extending the museum beyond its physical walls. This issue takes an in-depth look at the science and history of paper. Topics include: (1) Fascinating Facts about Paper; (2) A Closer Look at the Paper in This Magazine; (3) Handmade Paper; (4) Paper Airplanes; (5)…

  2. Paper electronics. (United States)

    Tobjörk, Daniel; Österbacka, Ronald


    Paper is ubiquitous in everyday life and a truly low-cost substrate. The use of paper substrates could be extended even further, if electronic applications would be applied next to or below the printed graphics. However, applying electronics on paper is challenging. The paper surface is not only very rough compared to plastics, but is also porous. While this is detrimental for most electronic devices manufactured directly onto paper substrates, there are also approaches that are compatible with the rough and absorptive paper surface. In this review, recent advances and possibilities of these approaches are evaluated and the limitations of paper electronics are discussed.

  3. Audio Papers

    DEFF Research Database (Denmark)

    Groth, Sanne Krogh; Samson, Kristine


    With this special issue of Seismograf we are happy to present a new format of articles: Audio Papers. Audio papers resemble the regular essay or the academic text in that they deal with a certain topic of interest, but presented in the form of an audio production. The audio paper is an extension...

  4. Gas Chromatography (United States)

    Qian, Michael C.

    Gas chromatography (GC) has many applications in the analysis of food products. GC has been used for the determination of fatty acids, triglycerides, cholesterol, gases, water, alcohols, pesticides, flavor compounds, and many more. While GC has been used for other food components such as sugars, oligosaccharides, amino acids, peptides, and vitamins, these substances are more suited to analysis by high performance liquid chromatography. GC is ideally suited to the analysis of volatile substances that are thermally stable. Substances such as pesticides and flavor compounds that meet these criteria can be isolated from a food and directly injected into the GC. For compounds that are thermally unstable, too low in volatility, or yield poor chromatographic separation due to polarity, a derivatization step must be done before GC analysis. The two parts of the experiment described here include the analysis of alcohols that requires no derivatization step, and the analysis of fatty acids which requires derivatization. The experiments specify the use of capillary columns, but the first experiment includes conditions for a packed column.


    Institute of Scientific and Technical Information of China (English)

    Lorna Mansley


    <正>Take a sheet of paper, a pair of scissors or a knife, a vivid imagination and see what you can create. Synonymous with Chinese folkart, paper cutting no longer seems to be a flourishing craft amongst China’s younger generations of creatives, though its motifs can

  6. Recent progress on countercurrent chromatography modeling


    Wang, Fengkang; Ito, Yoichiro; Wei, Yun


    As countercurrent chromatography is becoming an established method in chromatography for many kinds of products, it is becoming increasingly important to model the process and to be able to predict the peaks for a given process. The CCC industries are looking for rapid methods to analyze the processes of countercurrent chromatography and select suitable solvent system. In this paper, recent progress is reviewed in the development and demonstration of several types of models of countercurrent ...

  7. Poster papers (United States)

    Schulz, Michael

    In many scientific societies, presentation by poster has become a popular alternative to oral delivery for contributed papers at major meetings. This has not been so in the AGU. My purpose in this 'editorial' is to acquaint the AGU membership with some of the advantages of the poster paper as an occasional alternative to the 10-minute talk.The main advantage for the author of a poster paper is the opportunity for interaction with an interested audience for a 3 hour period. Significant feedback from the audience is a bonus that gives the author a better understanding of his own work and how to explain it, both orally and in print. Those of us who have tried poster presentation have found it to be a very positive experience.

  8. Mathematical papers

    CERN Document Server

    Green, George


    An almost entirely self-taught mathematical genius, George Green (1793 -1841) is best known for Green's theorem, which is used in almost all computer codes that solve partial differential equations. He also published influential essays, or papers, in the fields of hydrodynamics, electricity, and magnetism. This collection comprises his most significant works.The first paper, ""An Essay on the Application of Mathematical Analysis to the Theories of Electricity and Magnetism,"" which is also the longest and perhaps the most Important, appeared In 1828. It introduced the term potential as desig

  9. Panama Papers

    DEFF Research Database (Denmark)

    Harrington, Brooke


    Mossack Fonseca kept its clients largely on the right side of the law. Indeed, that’s entirely the point. This article for The Atlantic draws on my wealth management research to explain why most of what is revealed in the Panama Papers leak will not result in criminal prosecution for anyone...

  10. Instrumentation: Ion Chromatography. (United States)

    Fritz, James S.


    Discusses the importance of ion chromatography in separating and measuring anions. The principles of ion exchange are presented, along with some applications of ion chromatography in industry. Ion chromatography systems are described, as well as ion pair and ion exclusion chromatography, column packings, detectors, and programming. (TW)

  11. Thin Layer Chromatography (TLC) of Chlorophyll Pigments. (United States)

    Foote, Jerry


    Background information, list of materials needed, procedures used, and discussion of typical results are provided for an experiment on the thin layer chromatography of chlorophyll pigments. The experiment works well in high school, since the chemicals used are the same as those used in paper chromatography of plant pigments. (JN)

  12. Panama Papers

    DEFF Research Database (Denmark)

    Harrington, Brooke


    Mossack Fonseca kept its clients largely on the right side of the law. Indeed, that’s entirely the point. This article for The Atlantic draws on my wealth management research to explain why most of what is revealed in the Panama Papers leak will not result in criminal prosecution for anyone......, and why government officials face nearly insurmountable obstacles to stopping the kind of financial games in which Mossack Fonseca and its counterparts engage....

  13. Illustrating Chromatography with Colorful Proteins (United States)

    Lefebvre, Brian G.; Farrell, Stephanie; Dominiak, Richard S.


    Advances in biology are prompting new discoveries in the biotechnology, pharmaceutical, medical technology, and chemical industries. This paper presents a detailed description of an anion exchange chromatography experiment using a pair of colorful proteins and summarizes the effect of operating parameters on protein separation. This experiment…

  14. Selected papers

    CERN Document Server

    Elgot, Calvin C


    Cal Elgot was a very serious and thoughtful researcher, who with great determi­ nation attempted to find basic explanations for certain mathematical phenomena­ as the selection of papers in this volume well illustrate. His approach was, for the most part, rather finitist and constructivist, and he was inevitably drawn to studies of the process of computation. It seems to me that his early work on decision problems relating automata and logic, starting with his thesis under Roger Lyndon and continuing with joint work with Biichi, Wright, Copi, Rutledge, Mezei, and then later with Rabin, set the stage for his attack on the theory of computation through the abstract treatment of the notion of a machine. This is also apparent in his joint work with A. Robinson reproduced here and in his joint papers with John Shepherdson. Of course in the light of subsequent work on decision problems by Biichi, Rabin, Shelah, and many, many others, the subject has been placed on a completely different plane from what it was whe...

  15. GC -MS法研究纸杯中有机残留物向食品的迁移行为%Migration behavior of organic residues to food in paper cups by gas chromatography-mass spectrometry

    Institute of Scientific and Technical Information of China (English)



    Research for the migration behavior of organic residues to food simulants and real food and for the migration laws of different food stroma .By solvent extraction to extract or-ganic residued in the soak of paper cups and carried on the quantitative analysis by chroma -tography-mass spectrometry .Chose four kinds of food simulants and real foods which has close nature to them , soaking paper cups , determination of migration of organic residues . Detected 9 kinds of organic compounds from two brands of paper cup , residues have the same migration trend in food simulation and real food .The organic residue of paper cups mainly came from plasticizer and printing ink .The migration from these organic residues to alcohol is the most significant .%研究了有机残留物向食品模拟物和真实食品的迁移行为及在不同食品基质中的迁移规律。采用溶剂萃取法提取纸杯浸泡液中的有机残留物,进行GC-MS定量分析。选择四种食品模拟物和与之性质相近的食品,浸泡纸杯,测定有机残留物的迁移量。从两种品牌纸杯中共检出9中有机物,残留物在食品模拟物和食品中的迁移趋势一致。纸杯中的有机残留物主要来源于增塑剂和印刷油墨,这些有机残留物向酒精类食品的迁移最为显著。

  16. Paper justice. (United States)

    Culler, T A


    This article relates the case of two young girls who became pregnant as a result of rape and their efforts to exercise their rights to terminate the pregnancy. The first victim was a 12-year-old girl from Bolivia and the second was Paulina, a 13-year-old resident of Baja California, Mexico. Though abortion is illegal in both countries, in the case of rape the procedure is "unpunishable" in Bolivia and legal in Mexico. Despite these laws, the girls, their families and their advocates contend repeatedly with local government and Catholic Church officials on the issue. Only the first victim successfully exercised her right to terminate her pregnancy through the efforts of her family and the decision of Penal Judge Luis Ledezma. This paper also highlights the need for reforms in the abortion law in both countries.

  17. Determination of 26 kinds of residual solvent in cigarette paper by headspace gas chromatography mass spectrometry%顶空-气相色谱质谱联用法分析烟用纸张中26种溶剂残留物

    Institute of Scientific and Technical Information of China (English)

    杜显生; 张颖明; 侯鑫


    建立了烟用纸张中26种溶剂残留物的顶空—气相色谱质谱联用(HS-GCMS)研究方法。以三醋酸甘油酯作为溶剂,使用静态顶空仪对烟用纸张进行前处理,溶剂残留混合组分导入气相色谱仪中逐一分离,进入质谱检测器进行定性定量分析。结果表明:方法的回收率在87.1%~107.8%之间,检出限在0.001~0.204m g/m2之间,相对标准偏差(R S D)小于5%。该方法可同时检测烟用纸张中26种溶剂残留物。%A determination method of 26 kinds of solvent residual in cigarette paper by headspace gas chromatography mass spectrometry (HS-GCMS) was established. Cigarette paper sample was pretreated with static headspace sampling used glyceryl triacetate as dissolvent. The mixed solvent residues were separated speciifcally by gas chromatography mass spectrometry and were qualitatively and quantitatively analyzed in MS Detector. The results showed that this method has good relative standard deviation (RSD<5%). Recovery rate is 87.1% to 107.8% and the detection limit is 0.001 to 0.204mg/m2. So this testing method can be applied to determine 26 kinds residual solvent in cigarette paper simultaneously.

  18. Basic Principles of Chromatography (United States)

    Ismail, Baraem; Nielsen, S. Suzanne

    Chromatography has a great impact on all areas of analysis and, therefore, on the progress of science in general. Chromatography differs from other methods of separation in that a wide variety of materials, equipment, and techniques can be used. [Readers are referred to references (1-19) for general and specific information on chromatography.]. This chapter will focus on the principles of chromatography, mainly liquid chromatography (LC). Detailed principles and applications of gas chromatography (GC) will be discussed in Chap. 29. In view of its widespread use and applications, high-performance liquid chromatography (HPLC) will be discussed in a separate chapter (Chap. 28). The general principles of extraction are first described as a basis for understanding chromatography.

  19. 薄层色谱法鉴定原子印油印文盖印形成时间%Identifying stamping time of atomic seal ink on paper by thin layer chromatography

    Institute of Scientific and Technical Information of China (English)

    张凌燕; 潘自勤; 祁堃; 荣静月; 陈浩


    建立了用薄层色谱法鉴定原子印油印文盖印形成时间的新方法.详细研究了萃取剂、反应时间、反应温度等的影响,建立了萃取动力学曲线.在优化条件下,盖印时间在36个月内的新鲜原子印油印文,萃取速率值与盖印时间的线性方程为y=-0.0166x+0.7025(R2=0.9554),检测下线为3个月.用该方法对10余种原子印文盖印形成时间进行了鉴定,均有同样结果.%A novel method for identifying the stamping time of atomic seal ink on paper by thin layer chromato-graph was established. The influences of extractants, reaction time and reaction temperature were studied, and the dynamic extraction curves were plotted. Under the optimized conditions, the linear regression equation of the extraction rate and stamping time is y = 0. 166x + 0. 7025 (R2 = 0. 9554) for atomic seal ink stamped within 36 months with the lower detection limit of 3 months. The method has been used for identifying stamping times of more than 10 atomic seal ink of different brands and the similar results have been obtained.

  20. Peak broadening in paper chromatography and related techniques

    NARCIS (Netherlands)

    Ligny, C.L. de; Veen, N.G. van


    Peak dispersion (i.e. the separation efficiency) in thin-layer electrophoresis was investigated and compared for six different cellulose layers. The relative importance of longitudinal diffusion and of macroscopic inhomoeneities in the electric field and in the electroosmotic and sucking flow have

  1. Liquid Chromatography in 1982. (United States)

    Freeman, David H.


    Reviews trends in liquid chromatography including apparatus, factors affecting efficient separation of a mixture (peak sharpness and speed), simplified problem-solving, adsorption, bonded phase chromatography, ion selectivity, and size exclusion. The current trend is to control chemical selectivity by the liquid phase. (Author/JN)

  2. Column Liquid Chromatography. (United States)

    Majors, Ronald E.; And Others


    Reviews literature covering developments of column liquid chromatography during 1982-83. Areas considered include: books and reviews; general theory; columns; instrumentation; detectors; automation and data handling; multidimensional chromatographic and column switching techniques; liquid-solid chromatography; normal bonded-phase, reversed-phase,…

  3. 纸质食品接触材料的多环芳烃气相色谱/质谱-选择离子监测法测定%Determination of polycyclic aromatic hydrocarbons in paper packaging materials intended to come into contact with foodstuffs by gas chromatography/mass spectrometry-selected ion monitor technique

    Institute of Scientific and Technical Information of China (English)

    王成云; 杨左军; 徐嵘


    An effective gas chromatography/mass spectrometry-selected ion monitoring method was established for the simultaneous determination of the contents of 18 kinds of banned polycyclic aromatic hydrocarbons (PAHs) in paper packaging materials intended to come into contact with foodstuffs. PAHs in paper packaging materials intended to come into contact with foodstuffs were ifrst ultrasonically extracted at 40℃, using hexane/acetone (1:1) as the extraction solvent, then the extract was purified by silica solid phase extraction column, followed by the analysis of gas chromatography/mass spectrometry-selected ion monitor technique. The concentration of each analytes was calibrated by external standard method. The detection limits changed from 0.1μg/kg to 1.0μg/kg at the condition of signal to noise (S/N) of 3. The spiked average recoveries varied from 55.98% to 95.62% while the relative standard deviation (RSD) changed from 2.87% to 6.98%. At the same time, the coefficients were all larger than 0.997. The proposed method was simple, rapid, accurate and sensitive, and could satisfy completely the demand of the analysis of PAHs in paper packaging materials intended to come into contact with foodstuffs. This method was applied to the simultaneous determination of PAHs in commercially available paper packaging materials intended to come into contact with foodstuffs and phennanthrene of high content was detected in a warm beige regenerated packing bag.%建立了一个气相色谱/质谱-选择离子监测方法,对纸质食品接触材料中18种禁用多环芳烃进行了同时测定,该方法以正己烷/丙酮(1∶1)为提取溶剂,40℃下超声提取纸质食品接触材料中的多环芳烃,提取产物经硅胶固相萃取柱净化后进行气相色谱/质谱-选择离子监测法测定,外标法定量。在S/N=3的条件下,各目标化合物的检出限为0.1~1.0μg/kg。方法的加标平均回收率为55.98~95.62%,相对标准偏差为2.87~6

  4. 气相色谱-串联质谱法测定涂布纸中邻苯二甲酸酯类增塑剂%Simultaneous Determination of Phthalate Plasticizers in Coated Papers by Gas Chromatography-tandem Mass Spectrometry Coupled with Microwave-assisted Extraction

    Institute of Scientific and Technical Information of China (English)

    王成云; 徐嵘; 杨左军; 吴透明; 谢堂堂; 褚乃清


    以丙酮为萃取溶剂,采用微波辅助萃取技术提取涂布纸中的邻苯二甲酸酯类增塑剂,提取产物进行气相色谱-串联质谱法(GC-MS)测定,从而建立了一种同时测定涂布纸中多种邻苯二甲酸酯类增塑剂的快速检测方法.该方法的精密度(RSD)均小于14%,加标平均回收率为83.6% ~104.1%.在信噪比为10(S/N=10)的条件下,DINP、DIDP和DMPP的定量下限分别为0.2、0.2、0.1 mg/kg,其余各组分的定量下限均小于0.05 mg/kg.采用该方法对市售涂布纸进行测定,结果在部分涂布纸中检出多种邻苯二甲酸酯类增塑剂.%Phthalate plasticizers in coated papers were microwave-assisted extracted using acetone as the extraction solvent, and then were analyzed by gas chromatography-tandem mass spectrometry(GC-MS). Therefore, an effective method was established to determine simultaneously the contents of phthalate plasticizers in coated papers. The relative standard deviation (RSD) of the proposed method was less than 14% while the average spike recoveries varied from 83.6% to 104.1%. The quantification limits (S/N = 10) were 0.2, 0.2 and 0.1 mg/ kg for DINP, DIDP and DMPP, respectively. The limits of quantification (S/N = 10) were all less than 0.05 mg/kg for other phthalate plasticizers. The proposed method was successfully applied to the determination of phthalate plasticizers in coated papers and the results showed that various phthalate plasticizers existed in some commercial coated papers.

  5. 高压液相色谱法测定纸质食品接触材料中亚甲基双硫氰酸酯的迁移量%Determination of methylene dithiocyanate migration from food contact paper materials by high pressure liquid chromatography

    Institute of Scientific and Technical Information of China (English)

    丁岚; 马强; 李文涛; 马会娟; 李晶瑞; 孟宪双; 陈云霞; 白桦


      目的建立纸质食品接触材料中亚甲基双硫氰酸酯迁移量的高压液相色谱测定方法。方法食品模拟物(水、3%乙酸水溶液、10%乙醇水溶液和橄榄油)中的亚甲基双硫氰酸酯通过高压液相色谱进行分离,采用二极管阵列检测器进行测定。水基食品模拟物直接进样,油基食品模拟物经乙腈萃取后进样,外标法定量。结果3种水基食品模拟物中,亚甲基双硫氰酸酯在0.5~50 mg/L范围内线性关系良好,定量下限为0.5 mg/L,平均回收率为88.2%~97.4%,相对标准偏差为0.44%~6.54%;油基食品模拟物中,亚甲基双硫氰酸酯在1.0~20 mg/kg范围内线性关系良好,定量下限为1.0 mg/kg,平均回收率为99.3%~104.7%,相对标准偏差为0.75%~3.15%。结论该方法准确、简便、快速,可用于纸质食品接触材料中亚甲基双硫氰酸酯迁移量的实际检验工作。%Objective An analytical method for the detection of methylene dithiocyanate migration from food contact paper materials by high pressure liquid chromatography was established. Methods Methylene dithiocyanate migrated into the food simulants (water, 3%aqueous acetic acid solution, 10%aqueous ethanol solution and refined olive oil) was separated and detected by high pressure liquid chromatography coupled with diode array detector. The water-based food simulants were subjected to instrumental analysis directly and the oil-based food simulant was extracted by acetonitrile and then analyzed and quantitated with external standard method. Results This method showed a good linearity for methylene dithiocyanate in the range of 0.5~50 mg/L in the 3 water-based food simulants with the limit of quantification of 0.5 mg/L. The mean recoveries at three spiked levels were in the range of 88.2%~97.4%with relative standard deviations of 0.44%~6.54%. Me-thylene dithiocyanate exhibited a good linearity in the range of 1.0~20 mg/kg with the limit of quantification of 1.0 mg/kg. The mean

  6. Simultaneous determination of K+, Na+, Ca2+ and Mg2+ contents in cigarette paper by ultrasonic extraction-ion chromatography%超声波提取-离子色谱法同时测定卷烟纸中的钾、钠、钙、镁

    Institute of Scientific and Technical Information of China (English)

    陈伟华; 张艳芳; 鲍峰伟; 苏国岁


    用0.02 mol/L的盐酸溶液超声提取卷烟纸样品中的钾、钠、钙、镁4种离子,并采用离子色谱法进行同时测定.Ionpac CG12A(4mm×250mm)阳离子交换柱为固定相,15 mmol/L的甲烷基磺酸为流动相,电导检测器进行测定.结果表明:方法的检出限为0.02~0.69 mg/kg,加标回收率为90.14%~106.1%,相对标准偏差均小于5%,结果令人满意.%A method was studied for simultaneously determining the contents of potassium, sodium, magnesium and calcium in cigarette paper by ion chromatography. Four cations were extracted from the samples with 0.02 mol/L hydrochloric acid by ultrasonic extraction, separated on IonPac CS12A column (4 mm x250 mm) with 15 mmol/L methane -sulfuric acid as mobile phase, and detected with suppressed conductivity detector. The results showed that the detection limits were 0.02-0.69 mg/kg and the recoveries were ranged from 90.14%~106.1% , while the relative standard deviations were less than 5%.

  7. Normal and Reversed-Phase Thin Layer Chromatography of Green Leaf Extracts (United States)

    Sjursnes, Birte Johanne; Kvittingen, Lise; Schmid, Rudolf


    Introductory experiments of chromatography are often conducted by separating colored samples, such as inks, dyes, and plant extracts, using filter paper, chalk, or thin layer chromatography (TLC) plates with various solvent systems. Many simple experiments have been reported. The relationship between normal chromatography and reversed-phase…

  8. Use of Chromatography Techniques to Separate a Mixture of Substances (United States)

    Donaldson, W.


    Explains the separation of the constituents of mixtures on one piece of chromatography paper. The example presented involves a vitamin C tablet, a disprin tablet, and a glucose tablet. Outlined are two methods for separating the constituents. (GS)

  9. High Performance Liquid Chromatography (United States)

    Talcott, Stephen

    High performance liquid chromatography (HPLC) has many applications in food chemistry. Food components that have been analyzed with HPLC include organic acids, vitamins, amino acids, sugars, nitrosamines, certain pesticides, metabolites, fatty acids, aflatoxins, pigments, and certain food additives. Unlike gas chromatography, it is not necessary for the compound being analyzed to be volatile. It is necessary, however, for the compounds to have some solubility in the mobile phase. It is important that the solubilized samples for injection be free from all particulate matter, so centrifugation and filtration are common procedures. Also, solid-phase extraction is used commonly in sample preparation to remove interfering compounds from the sample matrix prior to HPLC analysis.

  10. Micellar Electrokinetic Chromatography (United States)

    Bald, Edward; Kubalczyk, Paweł

    Since the introduction of micellar electrokinetic chromatography by Terabe, several authors have paid attention to the fundamental characteristics of this separation method. In this chapter the theoretical and practical aspects of resolution optimization, as well as the effect of different separation parameters on the migration behavior are discussed. These among others include fundamentals of separation, retention factor and resolution equation, efficiency, selectivity, and various surfactants and additives. Initial conditions for method development and instrumental approaches such as mass spectrometry detection are also mentioned covering the proposals for overcoming the difficulties arising from the coupling micellar electrokinetic chromatography with mass spectrometry detection.

  11. Micellar liquid chromatography (United States)

    Basova, Elena M.; Ivanov, Vadim M.; Shpigun, Oleg A.


    Background and possibilities of practical applications of micellar liquid chromatography (MLC) are considered. Various retention models in MLC, the effects of the nature and concentration of surfactants and organic modifiers, pH, temperature and ionic strength on the MLC efficiency and selectivity are discussed. The advantages and limitations of MLC are demonstrated. The performance of MLC is critically evaluated in relationship to the reversed-phase HPLC and ion-pair chromatography. The potential of application of MLC for the analysis of pharmaceuticals including that in biological fluids and separation of inorganic anions, transition metal cations, metal chelates and heteropoly compounds is described. The bibliography includes 146 references.

  12. Size fractionation by slalom chromatography and hydrodynamic chromatography


    Dias, Ricardo P.


    Hydrodynamic chromatography, also called separation by flow, is based on the use of the parabolic flow profile occurring in open capillaries or in the pores from a column filled with non-porous particles. The hydrodynamic chromatography separation medium, if any, is much simpler than that from size exclusion chromatography (porous particles), the former technique being used in the size-fractionation of many colloids and macromolecules. The transition between hydrodynamic chromatography (obtai...

  13. Sugar composition and FT-IR analysis of exopolysaccharides produced by microbial isolates from paper mill slime deposits

    NARCIS (Netherlands)

    Verhoef, R.P.; Schols, H.A.; Blanco, A.; Siika-aho, M.; Ratto, M.; Buchert, J.; Lenon, G.; Voragen, A.G.J.


    Thirty exopolysaccharides (EPS) produced by bacteria isolated from biofilms or slimelayers from different paper and board mills in Finland, France and Spain were subjected to size exclusion chromatography and sugar compositional analysis. High performance size exclusion chromatography (HPSEC) analys

  14. Modern Thin-Layer Chromatography. (United States)

    Poole, Colin F.; Poole, Salwa K.


    Some of the important modern developments of thin-layer chromatography are introduced. Discussed are the theory and instrumentation of thin-layer chromatography including multidimensional and multimodal techniques. Lists 53 references. (CW)

  15. Chromatography in industry

    NARCIS (Netherlands)

    Schoenmakers, P.


    This review focuses on the chromatography research that has been carried out within industry or in close cooperation with industry and that has been reported in the scientific literature between 2006 and mid-2008. Companies in the health care sector, such as pharmaceutical and biotechnology companie

  16. High Performance Thin Layer Chromatography. (United States)

    Costanzo, Samuel J.


    Clarifies where in the scheme of modern chromatography high performance thin layer chromatography (TLC) fits and why in some situations it is a viable alternative to gas and high performance liquid chromatography. New TLC plates, sample applications, plate development, and instrumental techniques are considered. (JN)

  17. The Migrant Papers. Behavorial Science Working Paper. (United States)

    Harrison, Ira E.

    Four papers pertaining to health services for East Coast migrant workers are included in this publication. These papers are: (1) "The Crew Leader as a Broker with Implications for Health Service Delivery," (2) "Migrant Health Project with Implications for Health Service Delivery," (3) "Planned Change in a Migrant Health…

  18. Discrimination of eight chloramphenicol isomers by liquid chromatography tandem mass spectrometry in order to investigate the natural occurence of chloramphenicol

    NARCIS (Netherlands)

    Berendsen, B.J.A.; Zuidema, T.; Jong, de J.; Stolker, A.A.M.; Nielen, M.W.F.


    This paper describes the discrimination of eight different isomers of chloramphenicol (CAP), an antibiotic banned for use in food producing animals, by reversed phase and chiral liquid chromatography in combination with tandem mass spectrometric detection. Previously, by liquid chromatography couple

  19. Separation techniques: Chromatography


    Coskun, Ozlem


    Chromatography is an important biophysical technique that enables the separation, identification, and purification of the components of a mixture for qualitative and quantitative analysis. Proteins can be purified based on characteristics such as size and shape, total charge, hydrophobic groups present on the surface, and binding capacity with the stationary phase. Four separation techniques based on molecular characteristics and interaction type use mechanisms of ion exchange, surface adsorp...

  20. Efficient paper recycling


    Gregor-Svetec, Diana; Možina, Klemen; Blaznik, Barbara; Urbas, Raša; Vrabič Brodnjak, Urška; Golob, Gorazd


    Used paper and paper products are important raw material for paper and board industry. Paper recycling increases the material lifespan and is a key strategy that contributes to savings of primary raw material, reduction of energy and chemicals consumption, reduction of the impact on fresh water and improvement of waste management strategies. The paper recycling rate is still highly inhomogeneous among the countries of Central Europe. Since recovered paper is not only recycled in the country w...

  1. Principles of Liquid Chromatography (United States)

    Bakalyar, Stephen R.

    This article reviews the basic principles of high performance liquid chromatography (HPLC). The introductory section provides an overview of the HPLC technique, placing it in historical context and discussing the elementary facts of the separation mechanism. The next section discusses the nature of resolution, describing the two principal aspects, zone center separation and zone spreading. The third section takes a detailed look at how HPLC is used in practice to achieve a separation. It discusses the three key variables that need to be adjusted: retention, efficiency, and selectivity. A fourth section is concerned with various relationships of practical importance: flow rate, temperature, and pressure. A final section discusses future trends in HPLC.

  2. Silica coated paper substrate for paper-spray analysis of therapeutic drugs in dried blood spots. (United States)

    Zhang, Zhiping; Xu, Wei; Manicke, Nicholas E; Cooks, R Graham; Ouyang, Zheng


    Paper spray is a newly developed ambient ionization method that has been applied for direct qualitative and quantitative analysis of biological samples. The properties of the paper substrate and spray solution have a significant impact on the release of chemical compounds from complex sample matrices, the diffusion of the analytes through the substrate, and the formation of ions for mass spectrometry analysis. In this study, a commercially available silica-coated paper was explored in an attempt to improve the analysis of therapeutic drugs in dried blood spots (DBS). The dichloromethane/isopropanol solvent has been identified as an optimal spray solvent for the analysis. The comparison was made with paper spray using chromatography paper as substrate with methanol/water as solvent for the analysis of verapamil, citalopram, amitriptyline, lidocaine, and sunitinib in dried blood spots. It has been demonstrated that the efficiency of recovery of the analytes was notably improved with the silica coated paper and the limit of quantitation (LOQ) for the drug analysis was 0.1 ng mL(-1) using a commercial triple quadrupole mass spectrometer. The use of silica paper substrate also resulted in a sensitivity improvement of 5-50-fold in comparison with chromatography papers, including the Whatman ET31 paper used for blood cards. Analysis using a hand-held miniature mass spectrometer Mini 11 gave LOQs of 10-20 ng mL(-1) for the tested drugs, which is sufficient to cover the therapeutic ranges of these drugs.

  3. Extension of the selection of protein chromatography and the rate model to affinity chromatography. (United States)

    Sandoval, G; Shene, C; Andrews, B A; Asenjo, J A


    The rational selection of optimal protein purification sequences, as well as mathematical models that simulate and allow optimization of chromatographic protein purification processes have been developed for purification procedures such as ion-exchange, hydrophobic interaction and gel filtration chromatography. This paper investigates the extension of such analysis to affinity chromatography both in the selection of chromatographic processes and in the use of the rate model for mathematical modelling and simulation. Two affinity systems were used: Blue Sepharose and Protein A. The extension of the theory developed previously for ion-exchange and HIC chromatography to affinity separations is analyzed in this paper. For the selection of operations two algorithms are used. In the first, the value of η, which corresponds to the efficiency (resolution) of the actual chromatography and, Σ, which determines the amount of a particular contaminant eliminated after each separation step, which determines the purity, have to be determined. It was found that the value of both these parameters is not generic for affinity separations but will depend on the type of affinity system used and will have to be determined on a case by case basis. With Blue Sepharose a salt gradient was used and with Protein A, a pH gradient. Parameters were determined with individual proteins and simulations of the protein mixtures were done. This approach allows investigation of chromatographic protein purification in a holistic manner that includes ion-exchange, HIC, gel filtration and affinity separations for the first time.

  4. Audio Papers - A Manifesto

    DEFF Research Database (Denmark)

    Krogh Groth, Sanne; Samson, Kristine


    Audio papers resemble the regular essay or the academic text in that they deal with a certain topic of interest, but presented in the form of an audio production. The audio paper is an extension of the written paper through its specific use of media, a sonic awareness of aesthetics and materiality......, and creative approach towards communication. The audio paper is a performative format working together with an affective and elaborate understanding of language. It is an experiment embracing intellectual arguments and creative work, papers and performances, written scholarship and sonic aesthetics....

  5. The physics of paper

    Energy Technology Data Exchange (ETDEWEB)

    Alava, Mikko [Helsinki University of Technology, Laboratory of Physics, PO Box 1100, 02015 HUT (Finland); Niskanen, Kaarlo [KCL Science and Consulting, PO Box 70, 02150 Espoo (Finland)


    Paper is a material known to everybody. It has a network structure consisting of wood fibres that can be mimicked by cooking a portion of spaghetti and pouring it on a plate, to form a planar assembly of fibres that lie roughly horizontal. Real paper also contains other constituents added for technical purposes. This review has two main lines of thought. First, in the introductory part, we consider the physics that one encounters when 'using' paper, an everyday material that exhibits the presence of disorder. Questions arise, for instance, as to why some papers are opaque and others translucent, some are sturdy and others sloppy, some readily absorb drops of liquid while others resist the penetration of water. The mechanical and rheological properties of paper and paperboard are also interesting. They are inherently dependent on moisture content. In humid conditions paper is ductile and soft, in dry conditions brittle and hard. In the second part we explain in more detail research problems concerned with paper. We start with paper structure. Paper is made by dewatering a suspension of fibres starting from very low content of solids. The processes of aggregation, sedimentation and clustering are familiar from statistical mechanics. Statistical growth models or packing models can simulate paper formation well and teach a lot about its structure. The second research area that we consider is the elastic and viscoelastic properties and fracture of paper and paperboard. This has traditionally been the strongest area of paper physics. There are many similarities to, but also important differences from, composite materials. Paper has proved to be convenient test material for new theories in statistical fracture mechanics. Polymer physics and memory effects are encountered when studying creep and stress relaxation in paper. Water is a 'softener' of paper. In humid conditions, the creep rate of paper is much higher than in dry conditions. The third among

  6. An Undergraduate Column Chromatography Experiment. (United States)

    Danot, M.; And Others


    Background information, list of materials needed, and procedures used are provided for an experiment designed to introduce undergraduate students to the theoretical and technical aspects of column chromatography. The experiment can also be shortened to serve as a demonstration of the column chromatography technique. (JN)

  7. Writing A Research Paper


    Cennetkusu, Nazmiye Gürel


    Writing a research paper in English as a foreign language for the first time is a challenging task for many international doctoral students. This study explores the challenges experienced and strategies utilized during the academic socialization process through research paper writing and within the framework of sociocultural theory. The results indicate that limited experience in research paper writing and personal writing style with cultural influence are the most challenging aspects. The ut...

  8. Robotics Strategy White Paper (United States)


    VIRGINIA 23651-1087 REPlY TO A1Tl!NTlON OF ATFC-DS 19 MEMORANDUM FOR SEE DISTRIBUTION SUBJECT: Robotics Strategy White Paper 1. The enclosed... Robotics Strategy White Paper is the result of a collaborative effort between the U.S. Anny Training and Doctrine Command (TRADOC) and the Tank-Automotive...Research, Development and Engineering Center (TARDEC). This paper builds on a confederated Anny robotics "strategy" that is described by senior leader

  9. Protein crystallization with paper (United States)

    Matsuoka, Miki; Kakinouchi, Keisuke; Adachi, Hiroaki; Maruyama, Mihoko; Sugiyama, Shigeru; Sano, Satoshi; Yoshikawa, Hiroshi Y.; Takahashi, Yoshinori; Yoshimura, Masashi; Matsumura, Hiroyoshi; Murakami, Satoshi; Inoue, Tsuyoshi; Mori, Yusuke; Takano, Kazufumi


    We developed a new protein crystallization method that incorporates paper. A small piece of paper, such as facial tissue or KimWipes, was added to a drop of protein solution in the traditional sitting drop vapor diffusion technique, and protein crystals grew by incorporating paper. By this method, we achieved the growth of protein crystals with reducing osmotic shock. Because the technique is very simple and the materials are easy to obtain, this method will come into wide use for protein crystallization. In the future, it could be applied to nanoliter-scale crystallization screening on a paper sheet such as in inkjet printing.

  10. Malaysia; Background Paper


    International Monetary Fund


    This Background Paper on Malaysia examines developments and trends in the labor market since the mid-1980s. The paper describes the changes in the employment structure and the labor force. It reviews wages and productivity trends and their effects on unit labor cost. The paper highlights that Malaysia’s rapid growth, sustained since 1987, has had a major impact on the labor market. The paper outlines the major policy measures to address the labor constraints. It also analyzes Malaysia’s r...

  11. INTRODUCTION Summary of Papers Summary of Papers (United States)

    Gauthier, Serge; Abarzhi, Snezhana I.; Sreenivasan, Katepalli R.


    review various aspects of Turbulent Mixing that were discussed at the Second International Conference and Advanced School 'Turbulent Mixing and Beyond', TMB-2009, held in summer 2009 at the Abdus Salam International Centre for Theoretical Physics (ICTP), Trieste, Italy. The papers are arranged by TMB themes and within each theme they are ordered alphabetically by the last name of the first author, with tutorials following research contributions. Canonical turbulence and turbulent mixing. The theme of canonical turbulence and turbulent mixing is considered by several authors. Casciola et al investigate the dynamics of inertial particles dispersed in a turbulent jet and compare their numerical modeling results with the classical similarity theory of the jet far-field. Remarkable agreement is found between the theory and the direct numerical simulations (DNS), including decay of Stokes numbers with the distance from the origin, self-similarity of the mean axial particle velocity profile, etc. Nagata considers complex turbulent flows, which are known to exhibit no linear critical point for the laminar states, and which are linearly stable at finite Reynolds numbers. Square duct flow and sliding Couette flow in an annulus are considered and nonlinear traveling-wave states are found for the flows with the use of the homotopy approach developed by the author. These states may constitute a skeleton around which a time-dependent trajectory in the phase space is organized. Teitelbaum and Mininni study a decaying 3D incompressible turbulence, which mimicks turbulent mixing in geophysical flows, with rotation rendering the flow anisotropic at large scales. The authors analyze three DNS results (without and with rotation, and with helicity), observe a decoupling of the modes normal to the rotation axis, and show that the helicity decreases the decay rate of turbulence. Wang and Peters investigate the structure of turbulence by studying strain rates of various scalars, including a

  12. CATV Technical Papers. (United States)

    National Cable Television Association, Inc., Washington, DC.

    Complete technical papers of the 1977 National Cable Television Association Convention are included in this report. Twenty-two of 32 papers and two abstracts cover the topics of advanced cable television techniques, human reactions to television picture impairment, special displays and services, protection from theft of service, everyday…


    Directory of Open Access Journals (Sweden)

    A. P. Nesenchuk


    Full Text Available The paper considers problems pertaining to methodology and structure for dissertation preparation. All the problems have been solved on the basis of the analysis of questionnaire complexes. The paper presents concrete examples taken from the dissertations that have passed expertise of the Highest Certifying Commission.

  14. Crepe Paper Colorimetry. (United States)

    Pringle, David L.; And Others


    Uses crepe paper for the introduction of spectrophotometric concepts. Dyes used in the manufacturing of the crepe paper dissolve rapidly in water to produce solutions of colors. The variety of colors provides spectra in the visible spectrum that allow students to grasp concepts of absorption and transmission. (AIM)

  15. Paper Highlight — Site (United States)

    In a recent paper published in Cancer Cell, ICBP investigators at the University of Texas Health Science Center, want to provide the potential mechanistic explanation how the known 20q13 and 17q23 amplicons transcriptionally control gene expression through long-range chromatin proximity. This paper describes how different large sets of data can be integrated for finding new biological mechanisms.

  16. Transportation: Topic Paper E. (United States)

    National Council on the Handicapped, Washington, DC.

    As one of a series of topic papers assessing federal laws and programs affecting persons with disabilities, this paper reviews the issue of transportation services. In the area of urban mass transit, four relevant pieces of legislation and public transportation accessibility regulations are cited, and cost issues are explored. Paratransit systems,…

  17. Wrinkling of wet paper (United States)

    Kim, Ho-Young; Kim, Jungchul; Mahadevan, L.


    It is a mundane experience that paper stained with water wrinkles. It is because a wetted portion of paper, which swells due to the hygroexpansive nature of the cellulose fiber network, deforms out of its original plane. Here we quantify the dynamics of wrinkling of wet paper coupled to the capillary imbibition of water into paper using a combination of experiment and theory. While supplying water from a capillary tube that touches the center of a paper strip, we measure the spreading rate of the wet area, wait time for the out-of-plane buckling, and temporal growth of a wrinkling magnitude. Using a theoretical model assuming a linear increase of the strain and an exponential decay of the elastic modulus with the water concentration, we construct scaling laws to predict the simultaneous capillary imbibition and wrinkling rates. This work was supported by the Wyss Institute of Harvard University.

  18. Link to paper (United States)

    U.S. Environmental Protection Agency — Link to the paper. This dataset is associated with the following publication: Naile, J., A.W. Garrison, J. Avants, and J. Washington. Isomers/enantiomers of...

  19. Paper Gains and Losses

    Institute of Scientific and Technical Information of China (English)



    Wet piles of old cardboard are stacked on both sides of a loading platform, leaving just enough room for a truck to stop between them. Zhang Guanan, the stocky general manager of the Liudian General Paper Mill Factory, stands in the middle of the space. Behind him is the roar of a paper mill and a long flatbed truck leaving a warehouse loaded with twenty-eight giant rolls of carton board destined for a box

  20. Abstracts of contributed papers

    Energy Technology Data Exchange (ETDEWEB)


    This volume contains 571 abstracts of contributed papers to be presented during the Twelfth US National Congress of Applied Mechanics. Abstracts are arranged in the order in which they fall in the program -- the main sessions are listed chronologically in the Table of Contents. The Author Index is in alphabetical order and lists each paper number (matching the schedule in the Final Program) with its corresponding page number in the book.

  1. Quantum interaction. Selected papers

    Energy Technology Data Exchange (ETDEWEB)

    Atmanspacher, Harald [Eidgenoessische Technische Hochschule, Zurich (Switzerland); Haven, Emmanuel [Leicester Univ. (United Kingdom). School of Management; Kitto, Kirsty [Queensland Univ. of Technology, Brisbane, QLD (Australia); Raine, Derek (ed.) [Leicester Univ. (United Kingdom). Centre for Interdisciplinary Science


    This book constitutes the refereed proceedings of the 7th International Conference on Quantum Interaction, QI 2013, held in Leicester, UK, in July 2013. The 31 papers presented in this book were carefully selected from numerous submissions. The papers cover various topics on quantum interaction and revolve around four themes: information processing/retrieval/semantic representation and logic; cognition and decision making; finance/economics and social structures and biological systems.

  2. Nanotechnology in paper electronics (United States)

    Demming, Anna; Österbacka, Professor Ronald; Han, Jin-Woo, Dr


    The ability to put cutting edge technology on paper—not in words but in a working physical form—has been attracting an increasing number of researchers over the past decade. Paper has many advantages that make it attractive for flexible electronics: it is relatively environmentally benign; it is renewable; it can be recycled; it is light weight; production processes for paper are well advanced; and it is inexpensive. This special issue, with guest editors Ronald Österbacka from Åbo Akademi University in Finland and Jin-Woo Han from the NASA AMES Research Center, features some of the latest in paper electronics research, including developments towards applications in displays, sensing and alternative energy sources, as well as fundamental studies to further our understanding of how paper can be most effectively used in electronics. As Andrew Steckl and colleagues in the US point out, 'Cellulose-based paper substrates were implemented as an electronic substrate as early as 1969, with most advancement occurring in the past decade largely due to technology improvements in thin film deposition and organic materials' [1, 2]. They report a detailed comparison between paper, standard liquid crystal display rigid glass and flexible glass for hosting pentacene organic thin film transistors, and obtain promising results for future paper-based devices. As most meaningful electronic devices rely on transistors to function, transistors feature quite prominently in this special issue. Rodrigo Martins and colleagues in France and Portugal study the effect of fibre type, structure and dimension on paper-based transistors and reveal further insights into how paper properties affect device performance [3]. Qing Wan and colleagues in China bring the state of the art in transistor technology to paper substrates [4], fabricating indium-zinc-oxide (IZO)-based protonic/electronic hybrid thin film transistors on paper and showing that they can be used as artificial synapses. Like the

  3. Online Paper Review Analysis

    Directory of Open Access Journals (Sweden)

    Doaa Mohey El-Din


    Full Text Available Sentiment analysis or opinion mining is used to automate the detection of subjective information such as opinions, attitudes, emotions, and feelings. Hundreds of thousands care about scientific research and take a long time to select suitable papers for their research. Online reviews on papers are the essential source to help them. The reviews save reading time and save papers cost. This paper proposes a new technique to analyze online reviews. It is called sentiment analysis of online papers (SAOOP. SAOOP is a new technique used for enhancing bag-of-words model, improving the accuracy and performance. SAOOP is useful in increasing the understanding rate of review's sentences through higher language coverage cases. SAOOP introduces solutions for some sentiment analysis challenges and uses them to achieve higher accuracy. This paper also presents a measure of topic domain attributes, which provides a ranking of total judging on each text review for assessing and comparing results across different sentiment techniques for a given text review. Finally, showing the efficiency of the proposed approach by comparing the proposed technique with two sentiment analysis techniques. The comparison terms are based on measuring accuracy, performance and understanding rate of sentences.

  4. Calcium-sensitive immunoaffinity chromatography

    DEFF Research Database (Denmark)

    Henriksen, Maiken L; Lindhardt Madsen, Kirstine; Skjoedt, Karsten


    Immunoaffinity chromatography is a powerful fractionation technique that has become indispensable for protein purification and characterization. However, it is difficult to retrieve bound proteins without using harsh or denaturing elution conditions, and the purification of scarce antigens...... to homogeneity may be impossible due to contamination with abundant antigens. In this study, we purified the scarce, complement-associated plasma protein complex, collectin LK (CL-LK, complex of collectin liver 1 and kidney 1), by immunoaffinity chromatography using a calcium-sensitive anti-collectin-kidney-1 m...... chromatography was superior to the traditional immunoaffinity chromatographies and resulted in a nine-fold improvement of the purification factor. The technique is applicable for the purification of proteins in complex mixtures by single-step fractionation without the denaturation of eluted antigens...

  5. Recycling Paper Recycling

    Directory of Open Access Journals (Sweden)

    Martin A. Hubbe


    Full Text Available What do you do after a product has served its function and is no longer needed? Ideally, you recycle it. What do you do if people have neglected or forgotten so much of what has been learned in recent years about paper recycling? Well, one of the things that someone can do is to write a book. Very little of the contents of such a book may be new. But the book itself can be highly valuable, representing a lot of effort to select and organized material that will be helpful for the current and upcoming generations of papermaking technologists. This editorial describes a new book by Dr. Pratima Bajpai entitled Recycling and Deinking of Recovered Paper. Readers who deal with the recycling of paper will probably want to have a copy of it on a handy shelf.

  6. Call for Papers

    Institute of Scientific and Technical Information of China (English)


    <正>Internet Law Review is a scholarly monographic series focused on the research of internet law.It is sponsored by School of Intellectual Property,Peking University,and Internet Law Center of Peking University,edited by Professor Zhang Ping,and published twice a year. We are now preparing for the forthcoming issue of the Review,Volume 13,and prospective authors with new ideas,comprehensive and sound research methods and theories,and great creativity,are invited to submit your articles.Also,we strongly welcome excellent papers with high practicality and supported by detailed examples,and critical review papers to

  7. Recent advances in ultra-high performance liquid chromatography for the analysis of traditional chinese medicine (United States)

    Traditional Chinese medicines (TCMs) have been widely used for the prevention and treatment of various diseases for thousands of years in China. Ultra Performance Liquid Chromatography (UHPLC) is a relatively new technique offering new possibilities in liquid chromatography. This paper reviews recen...

  8. New methods and materials for solid phase extraction and high performance liquid chromatography

    Energy Technology Data Exchange (ETDEWEB)

    Dumont, Philip John [Iowa State Univ., Ames, IA (United States)


    This paper describes methods for solid phase extraction and high performance liquid chromatography (HPLC). The following are described: Effects of Resin Sulfonation on the Retention of Polar Organic Compounds in Solid Phase Extraction; Ion-Chromatographic Separation of Alkali Metals In Non-Aqueous Solvents; Cation-Exchange Chromatography in Non-Aqueous Solvents; and Silicalite As a Stationary Phase For HPLC.

  9. A Position Paper. (United States)

    Hixson, Richard A.

    This position paper covers possible problems of collective bargaining. (1) The two sides should not bring prejudgments of good or bad to the negotiating table. (2) Neither side should exaggerate its strength or minimize its weakness. (3) Neither side should confuse intransigence with firmness. (4) The composition of each team must be carefully…

  10. Writing on wet paper (United States)

    Fridrich, Jessica; Goljan, Miroslav; Lisonek, Petr; Soukal, David


    In this paper, we show that the communication channel known as writing in memory with defective cells is a relevant information-theoretical model for a specific case of passive warden steganography when the sender embeds a secret message into a subset C of the cover object X without sharing the selection channel C with the recipient. The set C could be arbitrary, determined by the sender from the cover object using a deterministic, pseudo-random, or a truly random process. We call this steganography "writing on wet paper" and realize it using low-density random linear codes with the encoding step based on the LT process. The importance of writing on wet paper for covert communication is discussed within the context of adaptive steganography and perturbed quantization steganography. Heuristic arguments supported by tests using blind steganalysis indicate that the wet paper steganography provides improved steganographic security for embedding in JPEG images and is less vulnerable to attacks when compared to existing methods with shared selection channels.

  11. Abstracts of Selected Papers

    Institute of Scientific and Technical Information of China (English)


    The present inflation is compound inflation influenced by internal and external factors. The paper brings forward three stages of supply changes of working-age population: 1) Not until 2010, the first stage can be described as a buyer's market of labor, i

  12. Paper relief architecture

    NARCIS (Netherlands)

    Latka, J.F.


    The article presents two contemporary projects of paper structures relief architecture designed and built by Shigeru Ban Architects and Voluntary Architect Network. Author of the article took part in design and construction process of one of the projects. The project of Yaan Nursery School, which wa

  13. Working Paper No.1 (United States)

    Graff, Harvey J.; Street, Brian V.; Jones, Stan


    This document is a collection of three parts: two extended papers and one shorter commentary on the International Adult Literacy Survey (IALS). These originally appeared in "Literacy Across the Curriculum" in response to an invitation for comment to several prominent international researchers. The first of these entitled "The…

  14. Pencil and paper

    DEFF Research Database (Denmark)

    Wong, Bang; Kjærgaard, Rikke Schmidt


    Creating pictures is integral to scientific thinking. In the visualization process, putting pencil to paper is an essential act of inward reflec- tion and outward expression. It is a constructive activity that makes our thinking specific and explicit. Compared to other constructive approaches...

  15. Regional Activities Division. Papers. (United States)

    International Federation of Library Associations, The Hague (Netherlands).

    Papers on library network activities in Canada, the Third World, Japan, Malaysia, Brazil, and Sweden which were presented at the 1982 International Federation of Library Associations (IFLA) conference include: (1) "Canada: A Voluntary and Flexible Network," a review by Guy Sylvestre of the political, social, and economic structures affecting…

  16. Call for papers

    Institute of Scientific and Technical Information of China (English)


    <正>Chinese Journal of Library and Information Science invites submission of academic papers from library and information science practitioners,educators and researchers.This peer-reviewed academic journal in the subject field of Library and Information Science(LIS)is published quarterly under the aegis of the National

  17. iPhone paper (United States)


    Could you write a scientific manuscript using just your iPhone? Well, when Christoph Bartneck at the University of Canterbury in New Zealand was invited to submit a paper to the International Conference on Atomic and Nuclear Physics, in Atlanta, Georgia, in November, he decided to do just that.

  18. Two three pages papers

    NARCIS (Netherlands)

    Apt, K.R.; Constable, R.L.; Silva, A.


    Dexter was my manager during the first 8 months or so of my one year stay at the IBM Research Center at Yorktown Heights in the mid eighties. Our interaction in terms of scientific output was very slim — it consisted of just a single paper, titled "Limits for automatic verification of finite-state c

  19. From Paper to PDA

    DEFF Research Database (Denmark)

    Kanstrup, Anne Marie; Stage, Jan


    Mobile devices with small screens and minimal facilities for interaction are increasingly being used in complex human activities for accessing and processing information, while the user is moving. This paper presents a case study of the design and evaluation of a mobile system, which involved...

  20. Student Investigations Using Chromatography (United States)

    Witters, Weldon L.; Bush, Kenneth


    Three different problems are given for student investigation in determining amino acid compositions, floral pigments, and water soluble amino acids by using the techniques of Roll Chromotography, DISC Chromotography, Thin Layer, and Paper Chromotography. (BR)

  1. Abstracts of Selected Papers

    Institute of Scientific and Technical Information of China (English)


    On the Social Solidarity of Organization An Empirical Analysis Li Hanlin Abstract: Based on the 2002 survey data, this paper tries to measure solidarity in organization. The operationalization for this measurement goes from two points of view. One is from the degree of cohesion and another one is from the degree of vulnerability. To observe and measure the degree of cohesion three subscales like social support, vertical integration and organizational identity have been used. To observe and measure the degree of vulnerability other three subscales like dissatisfaction, relative deprivation and anomie have been used. The paper tries to explore finally under which condition the organization behavior and behavior orientation could go to the similarity or make some difference. Key words: Organization Cohesion Vulnerability Organization Behavior

  2. Despre inovare. Working paper

    Directory of Open Access Journals (Sweden)

    Marina Mihăilă


    Full Text Available Innovation is at the heart of social and economic development. Although an important sector that generates products and services of high social and economic importance, construction sector is considered to be an underachiever in terms of innovation. This working paper briefly explores the state of innovation within construction sector, considering European tendencies, theoretical and practical developments and challenges raised by particular characteristic of construction products. Some preliminary conclusions are underlined as the basis for further extensive research.

  3. Call for papers

    Institute of Scientific and Technical Information of China (English)


    <正>Chinese Journal of Library and Information Science invites submission of academic papers from library and information science practitioners,educators and researchers.This peer-reviewed academic journal in the subject field of Library and Information Science(LIS)is published quarterly under the aegis of the National Science Library,Chinese Academy of Sciences.The Journal is the first English-language academic journal in LIS ever published in

  4. Call for papers

    Institute of Scientific and Technical Information of China (English)


    <正>Chinese Journal of Library and Information Science invites submission of academic papers from library and information science practitioners,educators and researchers.This peer-reviewed academic journal in the subject field of Library and Information Science(LIS)is published quarterly under the aegis of the National Science Library,Chinese Academy of Sciences.The Journal is the first English-language academic journal in LIS ever published in mainland China that has an international readership in mind.

  5. Call for papers

    Institute of Scientific and Technical Information of China (English)


    <正>Chinese Journal of Library and Information Science invites submission of academic papers from library and information science practitioners,educators and researchers.This peer-reviewed academic journal in the subject field of Library and Information Science(LIS)is published quarterly under the aegis of the National Science Library,Chinese Academy of Sciences.The Journal is the first English-language academic journal in LIS ever published in Mainland China that has an international

  6. Call for papers

    Institute of Scientific and Technical Information of China (English)


    <正>Chinese Journal of Library and Information Science invites submission of academic papers from library and information science practitioners,educators and researchers.This peer-reviewed academic journal in the subject field of Library and Information Science(LIS)is published quarterly under the aegis of the National Science Library,Chinese Academy of Sciences.The Journal is the first English-language academic journal in LIS ever published in mainland

  7. Call for papers

    Institute of Scientific and Technical Information of China (English)


    <正>Chinese Journal of Library and Information Science invites submission of academic papers from library and information science practitioners,educators and researchers.This peer-reviewed academic journal in the subject field of Library and Information Science(LIS)is published quarterly under the aegis of the National Science Library,Chinese Academy of Sciences.The Journal is the first English-language academic journal in LIS ever published in mainland

  8. Outstanding student papers (United States)

    Five presentations in the Hydrology Section were named Outstanding Student Papers at AGU's Spring Meeting in Baltimore, Md.Gwynn R. Johnson was honored for her presentation of “Solvent Rushing of an LNAPL Contaminated Soil.” She received her bachelor's degree in May 1993 and is now completing her master's degree (under the guidance of M.D. Annable, P.S.C. Rao, and K. Hatfield) in the Department of Environmental Engineering Sciences at the University of Florida.

  9. Coupling of column liquid chromatography and Fourier transform infrared spectrometry

    NARCIS (Netherlands)

    Somsen, G.W; Gooijer, C; Velthorst, N.H; Brinkman, U.A Th


    This paper provides an extensive overview of the literature on the coupling of column liquid chromatography (LC) and Fourier transform infrared spectrometry (FT-IR). Flow-cell-based FT-IR detection and early solvent-elimination interfaces for LC-FT-IR are discussed in brief. A comprehensive descript

  10. Call for Papers

    Institute of Scientific and Technical Information of China (English)


    Chinese Nursing Research is a nursing academic journal,CN 14-1375/R,ISSN 2095-7718.Size A4,48 pages,quarterly publication,color printing,public offerings at home and abroad which is in charge of the First Hospital of Shanxi Medical University,sponsored by Chinese Nursing Association Shanxi Branch and Shanxi Medical Periodical Press.Chinese Nursing Research is an important platform of nursing academic exchange.The mission is to carry out related guidelines,policies and regulations of journals publication,to publish academic papers,review articles of nursing domain experts

  11. Call for papers

    Institute of Scientific and Technical Information of China (English)


    <正>Chinese Journal of Library and Information Science invites submission of academic papers from library and information science practitioners,educators and researchers.This peer-reviewed academic journal in the subject field of Library and Information Science(LIS)is published quarterly under the aegis of the National Science Library,Chinese Academy of Sciences.The Journal is the first English-language academic journal in LIS ever published in Mainland China that has an international readership in mind.This journal is aimed to establish a platform for LIS students,educators,researchers and library practitioners all over the world to engage in

  12. Call for papers

    Institute of Scientific and Technical Information of China (English)


    <正>Chinese Journal of Library and Information Science invites submission of academic papers from library and information science practitioners,educators and researchers.This peer-reviewed academic journal in the subject field of Library and Information Science(LIS)is published quarterly under the aegis of the National Science Library,Chinese Academy of Sciences.The Journal is the first English-language academic journal in LIS ever published in mainland China that has an international readership in mind.This journal is aimed to establish a platform for LIS students,educators,researchers and library practitioners all over the world to engage in

  13. Call for papers

    Institute of Scientific and Technical Information of China (English)


    <正>Chinese Journal of Library and Information Science invites submission of academic papers from library and information science practitioners,educators and researchers.This peer-reviewed academic journal in the subject field of Library and Information Science(LIS)is published quarterly under the aegis of the National Science Library,Chinese Academy of Sciences.The Journal is the first English-language academic journal in LIS ever published in mainland China that has an international readership in mind.This journal is aimed to establish a platform for LIS students,educators,researchers and library practitioners all over the world to engage in

  14. Call for papers

    Institute of Scientific and Technical Information of China (English)


    <正>Chinese Journal of Library and Information Science invites submission of academic papers from library and information science practitioners,educators and researchers.This peer-reviewed academic journal in the subject field of Library and Information Science(LIS)is published quarterly under the aegis of the National Science Library,Chinese Academy of Sciences.The Journal is the first English-language academic journal in LIS ever published in mainland China that has an international readership in mind.This journal is aimed to establish a platform for LIS students,educators,researchers and library practitioners


    Institute of Scientific and Technical Information of China (English)


    Introduction Spoken instructions are often surprisingly ineffective, especially when in a foreign language and across cultures. With any course, and particularly on ATT courses, there always seems to be a daunting amount of information for trainees to absorb. This paper will outline how Chongqing University attempted to address the procedures and problems of organising a teacher-training course by using what we, rather inaccurately, called "memos". Memos were written by the project team and given to each trainee. They borrowed the style of a newsletter, but in content they resembled, what are called in China, "open letters". They were printed about three times a semester, and usually contained five or six points of information. We intended them to be both informal and businesslike. The word ’memo’ seemed to embody all this so ’memos’ they became. In practice they were longer and more structured than the kind of memo you would leave on somebody’s desk. To illustrate this paper we use both excerpts from memos and statistics and quotations from trainees.

  16. Analysis of phenolic type antioxidants; Capillary gas chromatography

    Energy Technology Data Exchange (ETDEWEB)

    Chopra, S.K. (Indian Inst. of Petroleum, Dehradun (India)); Kapoor, V.B. (Indian Inst. of Petroleum, Dehradun (India)); Vishnoi, S.C. (Indian Inst. of Petroleum, Dehradun (India)); Bhagat, S.D. (Indian Inst. of Petroleum, Dehradun (India))


    A simple gas chromatographic (GC) procedure has been developed to estimate the individual alkylated phenols used as antioxidants to improve the shelf life of fuels and lubricants. Preparative gas chromatography was applied for separation and collection in sufficient quantity of the isomers of tertiary butyl, octyl and dodecyl phenols prepared by catalytic alkylation of phenol with isobutylene or its oligomers. The separated fractions were characterised by Infra-red spectrometry (IR) and paper chromatography. Out of several GC columns studies, a high resolution capillary column of 100% Methyl, Silicone gum (SE-30) as stationary phase gave best results. Data generated on various packed and capillary columns are in good agreement. (orig.)

  17. Position paper on mesotherapy

    Directory of Open Access Journals (Sweden)

    Rashmi Sarkar


    Full Text Available Mesotherapy is a controversial cosmetic procedure which has received publicity among the lay people, in the internet and in the media. It refers to minimally invasive techniques which consist of the use of intra- or subcutaneous injections containing liquid mixture of compounds (pharmaceutical and homeopathic medications, plant extracts, vitamins and other ingredients to treat local medical and cosmetic conditions. This position paper has examined the available evidence and finds that acceptable scientific evidence for its effectiveness and safety is lacking. IADVL taskforce, therefore would like to state that the use of this technique remains controversial at present. Further research and well-designed controlled scientific studies are required to substantiate the claims of benefit of this mode of therapy.

  18. Conical instabilities on paper

    Energy Technology Data Exchange (ETDEWEB)

    Guven, Jemal; Vazquez-Montejo, Pablo [Instituto de Ciencias Nucleares, Universidad Nacional Autonoma de Mexico, Apdo. Postal 70-543, 04510 Mexico, D.F. (Mexico); Mueller, Martin Michael, E-mail: [Equipe BioPhysStat, ICPMB-FR CNRS 2843, Universite Paul Verlaine-Metz, 1, boulevard Arago, 57070 Metz (France)


    The stability of the fundamental defects of an unstretchable flat sheet is examined. This involves expanding the bending energy to second order in deformations about the defect. The modes of deformation occur as eigenstates of a fourth-order linear differential operator. Unstretchability places a global linear constraint on these modes. Conical defects with a surplus angle exhibit an infinite number of states. If this angle is below a critical value, these states possess an n-fold symmetry labeled by an integer, n Greater-Than-Or-Slanted-Equal-To 2. A nonlinear stability analysis shows that the twofold ground state is stable, whereas excited states possess 2(n - 2) unstable modes which come in even and odd pairs. (paper)

  19. Call for papers

    Institute of Scientific and Technical Information of China (English)


    Chinese Journal of Library and Information Science invites submission of academic papers from library and information science practitioners,educators and researchers.This peer-reviewed academic journal in the subject field of Library and Information Science(LIS)is published quarterly under the aegis of the National Science Library,Chinese Academy of Sciences.The Journal is the first English-language academic journal in LIS ever published in mainland China that has an international readership in mind.This journal is aimed to establish a platform for LIS students,educators,researchers and library practitioners all over the world to engage in intellectual dialogue so as to upgrade continuously library practice around the world in general and that of China in particular.

  20. ILC Higgs White Paper

    CERN Document Server

    Asner, D M; Calancha, C; Fujii, K; Graf, N; Haber, H E; Ishikawa, A; Kanemura, S; Kawada, S; Kurata, M; Miyamoto, A; Neal, H; Ono, H; Potter, C; Strube, J; Suehara, T; Tanabe, T; Tian, J; Tsumura, J; Watanuki, S; Weiglein, G; Yagyu, K; Yokoya, H


    The ILC Higgs White Paper is a review of Higgs Boson theory and experiment at the International Linear Collider (ILC). Theory topics include the Standard Model Higgs, the two-Higgs doublet model, alternative approaches to electroweak symmetry breaking, and precision goals for Higgs boson experiments. Experimental topics include the measurement of the Higgs cross section times branching ratio for various Higgs decay modes at ILC center of mass energies of 250, 500, and 1000 GeV, and the extraction of Higgs couplings and the total Higgs width from these measurements. Luminosity scenarios based on the ILC TDR machine design are used throughout. The gamma-gamma collider option at the ILC is also discussed.

  1. Outstanding student papers (United States)

    Eight presentations were named Outstanding Student Papers in the Atmospheric Sciences Section at the 1995 Fall Meeting.Steve Davis, who presented “Reversal Effects in Wideband dE/dt from Lightning Measured at Multiple Ground Stations,” is currently attending the University of Florida pursuing a Ph.D. in electrical engineering. He graduated with high honors in 1990 with his bachelor's degree in electrical engineering from the University of Florida. He received his master's degree in 1992 from the University of Florida. The research for his master's degree was in the area of photonics with applications to laser and waveguide structures. His current research with Ewen Thomson involves measuring radiation from lightning at multiple ground stations. From these measurements, he hopes to determine lightning parameters such as velocities and currents and apply these to new and existing models.

  2. Metal-organic frameworks in chromatography. (United States)

    Yusuf, Kareem; Aqel, Ahmad; ALOthman, Zeid


    Metal-organic frameworks (MOFs) emerged approximately two decades ago and are the youngest class of porous materials. Despite their short existence, MOFs are finding applications in a variety of fields because of their outstanding chemical and physical properties. This review article focuses on the applications of MOFs in chromatography, including high-performance liquid chromatography (HPLC), gas chromatography (GC), and other chromatographic techniques. The use of MOFs in chromatography has already had a significant impact; however, the utilisation of MOFs in chromatography is still less common than other applications, and the number of MOF materials explored in chromatography applications is limited.

  3. Steroid monochloroacetates : Physical-chemical characteristics and use in gas-liquid chromatography

    NARCIS (Netherlands)

    Molen, H.J. van der; Groen, D.; Maas, J.H. van der


    Synthesis and physical-chemical characteristics (melting points, infrared-, visible- and ultraviolet spectra, paper-,thin-layer- and gas-liquid Chromatographie behaviour) of monochloroacetate derivatives of steroids representing the androstane-, pregnane-, estrane- and cholestane series are describe

  4. Fast methods for screening of trichothecenes in fungal cultures using gas chromatography-tandem mass spectrometry

    DEFF Research Database (Denmark)

    Nielsen, Kristian Fog; Thrane, Ulf


    The paper presents a fast method for trichothecene profiling and chemotaxonomic studies in species of Fusarium, Stachybotrys, Trichoderma and Memnoniella. Micro scale extracted crude Fusarium extracts were derivatised using pentafluoropropionic anhydride and analysed by gas chromatography...

  5. Hybrid method of solution applied to simulation of pulse chromatography

    Directory of Open Access Journals (Sweden)

    M. A. Cremasco


    Full Text Available In this communication, the method proposed by Cremasco et al. (2003 is applied to predict single and low concentration pulse chromatography. In previous work, a general rate model was presented to describe the breakthrough curve, where a hybrid solution was proposed for the linear adsorption. The liquid phase concentration inside the particle was found analytically and related with the bed liquid phase through Duhamel's Theorem, while the bulk-phase equation was solved by a numerical method. In this paper, this method is applied to describe pulse chromatography of solutes that present linear adsorption isotherms. The simulated results of pulse chromatography are compared with experimental ones for aromatic amino acid experiments from literature.

  6. Application of ion chromatography in clinical studies and pharmaceutical industry. (United States)

    Michalski, Rajmund


    Ion chromatography is a well-established regulatory method for analyzing anions and cations in environmental, food and many other samples. It offers an enormous range of possibilities for selecting stationary and mobile phases. Additionally, it usually helps to solve various separation problems, particularly when it is combined with different detection techniques. Ion chromatography can also be used to determine many ions and substances in clinical and pharmaceutical samples. It provides: availability of high capacity stationary phases and sensitive detectors; simple sample preparation; avoidance of hazardous chemicals; decreased sample volumes; flexible reaction options on a changing sample matrix to be analyzed; or the option to operate a fully-automated system. This paper provides a short review of the ion chromatography applications for determining different inorganic and organic substances in clinical and pharmaceutical samples.

  7. Environmental applications of ion chromatography in Eastern and Central Europe. (United States)

    Michalski, Rajmund


    Environmental analytics is one of the most important applications of ion chromatography. It includes determination of ions in water and wastewater as well as in gaseous and solid ones. Nowadays, ion chromatography has almost completely displaced the classical methods of ion determination in these areas. In spite of the fact that the ion chromatography has been officially present in the scientific world for 36 years, its role and popularity is highly diversified in various countries and regions of the world. In highly industrialized countries, it has been a reference method of water and wastewater analysis for years. In other parts of the world, it is not used and appreciated sufficiently despite its undeniable advantages. The following paper is a short overview of the most highly cited scientific and research institutions that conduct research in terms of environmental applications of ion chromatography in Eastern and Central Europe. Furthermore, the paper presents a list of a number of scientific papers referring to the discussed area, published in the years 1996-2009 in some of the most highly cited international scientific journals, and concerning publications of scientists from Eastern and Central Europe seen against the background of Europe and the world.

  8. Atomic Force Microscope Mediated Chromatography (United States)

    Anderson, Mark S.


    The atomic force microscope (AFM) is used to inject a sample, provide shear-driven liquid flow over a functionalized substrate, and detect separated components. This is demonstrated using lipophilic dyes and normal phase chromatography. A significant reduction in both size and separation time scales is achieved with a 25-micron-length column scale, and one-second separation times. The approach has general applications to trace chemical and microfluidic analysis. The AFM is now a common tool for ultra-microscopy and nanotechnology. It has also been demonstrated to provide a number of microfluidic functions necessary for miniaturized chromatography. These include injection of sub-femtoliter samples, fluidic switching, and sheardriven pumping. The AFM probe tip can be used to selectively remove surface layers for subsequent microchemical analysis using infrared and tip-enhanced Raman spectroscopy. With its ability to image individual atoms, the AFM is a remarkably sensitive detector that can be used to detect separated components. These diverse functional components of microfluidic manipulation have been combined in this work to demonstrate AFM mediated chromatography. AFM mediated chromatography uses channel-less, shear-driven pumping. This is demonstrated with a thin, aluminum oxide substrate and a non-polar solvent system to separate a mixture of lipophilic dyes. In conventional chromatographic terms, this is analogous to thin-layer chromatography using normal phase alumina substrate with sheardriven pumping provided by the AFM tip-cantilever mechanism. The AFM detection of separated components is accomplished by exploiting the variation in the localized friction of the separated components. The AFM tip-cantilever provides the mechanism for producing shear-induced flows and rapid pumping. Shear-driven chromatography (SDC) is a relatively new concept that overcomes the speed and miniaturization limitations of conventional liquid chromatography. SDC is based on a

  9. Extraction chromatography: Progress and opportunities

    Energy Technology Data Exchange (ETDEWEB)

    Dietz, M.L.; Horwitz, E.P.; Bond, A.H. [Argonne National Lab., IL (United States). Chemistry Div.


    Extraction chromatography provides a simple and effective method for the analytical and preparative-scale separation of a variety of metal ions. Recent advances in extractant design, particularly the development of extractants capable of metal ion recognition or of strong complex formation in highly acidic media, have significantly improved the utility of the technique. Advances in support design, most notably the introduction of functionalized supports to enhance metal ion retention, promise to yield further improvements. Column instability remains a significant obstacle, however, to the process-scale application of extraction chromatography. 79 refs.

  10. 40 CFR 247.10 - Paper and paper products. (United States)


    ... 40 Protection of Environment 24 2010-07-01 2010-07-01 false Paper and paper products. 247.10... COMPREHENSIVE PROCUREMENT GUIDELINE FOR PRODUCTS CONTAINING RECOVERED MATERIALS Item Designations § 247.10 Paper and paper products. Paper and paper products, excluding building and construction paper grades....

  11. Classic papers in combinatorics

    CERN Document Server

    Rota, Gian-Carlo


    This volume surveys the development of combinatorics since 1930 by presenting in chronological order the fundamental results of the subject proved in over five decades of original papers by:.-T. van Aardenne-Ehrenfest.-R.L. Brooks.-N.G. de Bruijn.-G.F. Clements.-H.H. Crapo.-R.P. Dilworth.-J. Edmonds.-P.Erdös.-L.R. Ford, Jr.-D.R. Fulkerson.-D. Gale.-L. Geissinger.-I.J. Good.-R.L. Graham.-A.W. Hales.-P. Hall.-P.R. Halmos.-R.I. Jewett.-I. Kaplansky.-P.W. Kasteleyn.-G. Katona.-D.J. Kleitman.-K. Leeb.-B. Lindström.-L. Lovász.-D. Lubell.-C. St. J.A. Nash-Williams.-G. Pólya.-F.P. Ramsey.-G.C. Rota.-B.L. Rothschild.-H.J. Ryser.-C. Schensted.-M.P. Schützenberger.-R.P. Stanley.-G. Szekeres.-W.T. Tutte.-H.E. Vaughan.-H. Whitney.

  12. Outstanding student paper awards (United States)

    The Atmospheric Sciences Section presented the following outstanding student paper awards at the AGU 1997 Fall Meeting in San Francisco, California, last December. James Corbett presented a poster on “Nitrogen and Sulfur Emissions From Oceangoing Ships.” James is a Ph.D. candidate in the Department of Engineering and Public Policy (EPP) at Carnegie Mellon University, Pittsburgh, Pa. He has been awarded a M.S. degree in EPP and recently completed the M.S. requirements in the Department of Mechanical Engineering. He graduated in 1985 with a degree in marine engineering technology from the California Maritime Academy and holds a California Professional Engineering License (Mechanical). He joined the doctoral program in engineering and public policy at Carnegie Mellon University in August 1995. In 1997, he was selected for a U.S. EPA STAR Fellowship. His research focuses on international maritime transportation and pollution issues, particularly air emissions from ship propulsion. James has developed the first global geographic characterization of air emissions from international maritime transport. As recently published in Science (Corbett and Fischbeck, 1997), his work estimates the global annual nitrogen and sulfur emissions from ships to be 3.08 terragrams (Tg) N and 4.24 Tg S, respectively.

  13. Outstanding student paper awards (United States)

    The Hydrology Section presented five outstanding student paper awards at the 1999 Spring Meeting in Boston, Massachusetts, last June.Maneesha Joshi presented a poster titled “Estimation of the Extent and Duration of Melt on the Greenland Ice Sheet using an Edge Detection Technique on Passive Microwave Data.” She received her B.Tech. in civil engineering from the Indian Institute of Technology, Bombay in 1991, and a M.S. in environmental engineering from State University of New York, Buffalo in 1994. Maneesha expects to complete her Ph.D. in civil engineering (remote sensing) in September 1999, under the supervision of Carolyn Merry (Department of Civil and Environmental Engineering & Geodetic Science), Ken Jezek, and John Bolzan (Byrd Polar Research Center) at the Ohio State University, Columbus, Ohio. Her thesis focuses on estimating the extent of melt, melt season, and duration, and absorbed radiation on the Greenland ice sheet from passive microwave and SAR data. Maneesha's other interests include image processing, issues related to global climate change, and photogrammetry.

  14. Discussions about high performance liquid chromatography upgrading to ion chromatography%液相色谱升级改造为离子色谱问题探讨

    Institute of Scientific and Technical Information of China (English)

    施超欧; 马浩; 姚宝龙; 黄彩勇


    离子色谱作为色谱的一个分支,在原理和仪器结构上与液相色谱密切相关。本文总结了液相色谱升级为离子改造色谱的经验。%As a part of chromatography ,the functions and structures of instruments between high per-formance liquid chromatography and ion chromatography are closely related .In this paper ,HPLC upgra-ded to IC was discused .

  15. Selectivity in microemulsion electrokinetic chromatography

    DEFF Research Database (Denmark)

    Pedersen-Bjergaard, S; Gabel-Jensen, Charlotte; Honoré Hansen, S


    Microemulsion electrokinetic chromatography (MEEKC) is a most promising separation technique providing good selectivity and high separation efficiency of anionic, cationic as well as neutral solutes. In MEEKC lipophilic organic solvents dispersed as tiny droplets in an aqueous buffer by the use...

  16. Liquid phase chromatography on microchips

    DEFF Research Database (Denmark)

    Kutter, Jörg Peter


    explosive development of, in particular, chromatographic separation systems on microchips, has, however, slowed down in recent years. This review takes a closer, critical look at how liquid phase chromatography has been implemented in miniaturized formats over the past several years, what is important...

  17. Bioaffinity chromatography on monolithic supports

    NARCIS (Netherlands)

    Tetala, K.K.R.; Beek, van T.A.


    Affinity chromatography on monolithic supports is a powerful analytical chemical platform because it allows for fast analyses, small sample volumes, strong enrichment of trace biomarkers and applications in microchips. In this review, the recent research using monolithic materials in the field of bi

  18. Two-dimensional liquid chromatography

    DEFF Research Database (Denmark)

    Græsbøll, Rune

    of this thesis is on online comprehensive two-dimensional liquid chromatography (online LC×LC) with reverse phase in both dimensions (online RP×RP). Since online RP×RP has not been attempted before within this research group, a significant part of this thesis consists of knowledge and experience gained...

  19. Review: Applications of chromatography in forensic sciences

    Directory of Open Access Journals (Sweden)

    Manoj S. Charde


    Full Text Available This article reviews the use of different Chromatography techniques in the forensic science, Chromatographic technique is very sensitive and selective. Different types of chromatography techniques used were Liquid chromatography -mass spectrometry, Gas chromatography–mass spectrometry, Thin layer chromatography, HPTLC in investigating criminal cases of which chemical warfare’s, terrorist attacks, smugglers, drug abuse, alcoholics. This techniques are promising to detect even pictogram or very less, with selectivity and sensitivity.


    Directory of Open Access Journals (Sweden)

    Yeghis Keheyan


    Full Text Available The thermal degradation of cellulose is an important process in several fields such as the paper industry, biomass combustion, fire retardation, etc. Paper consists mostly of cellulose fibres. Although the fibre source has changed continiously from cotton or linen rags to wood, its nature is still vegetal. Pyrolysis in combination with gas chromatography and mass spectrometry has been used to identify the structures of thermal degradation products with the aim to characterize papers used in different centuries. Pyrolysis of cellulose has also been studied in the presence of the methylating reagent tetramethylammonium hydroxide (TMAH.

  1. Lipidomics by Supercritical Fluid Chromatography

    Directory of Open Access Journals (Sweden)

    Laurent Laboureur


    Full Text Available This review enlightens the role of supercritical fluid chromatography (SFC in the field of lipid analysis. SFC has been popular in the late 1980s and 1990s before almost disappearing due to the commercial success of liquid chromatography (LC. It is only 20 years later that a regain of interest appeared when new commercial instruments were introduced. As SFC is fully compatible with the injection of extracts in pure organic solvent, this technique is perfectly suitable for lipid analysis and can be coupled with either highly universal (UV or evaporative light scattering or highly specific (mass spectrometry detection methods. A short history of the use of supercritical fluids as mobile phase for the separation oflipids will be introduced first. Then, the advantages and drawbacks of SFC are discussed for each class of lipids (fatty acyls, glycerolipids, glycerophospholipids, sphingolipids, sterols, prenols, polyketides defined by the LIPID MAPS consortium.

  2. Capillary Separation: Micellar Electrokinetic Chromatography (United States)

    Terabe, Shigeru


    Micellar electrokinetic chromatography (MEKC), a separation mode of capillary electrophoresis (CE), has enabled the separation of electrically neutral analytes. MEKC can be performed by adding an ionic micelle to the running solution of CE without modifying the instrument. Its separation principle is based on the differential migration of the ionic micelles and the bulk running buffer under electrophoresis conditions and on the interaction between the analyte and the micelle. Hence, MEKC's separation principle is similar to that of chromatography. MEKC is a useful technique particularly for the separation of small molecules, both neutral and charged, and yields high-efficiency separation in a short time with minimum amounts of sample and reagents. To improve the concentration sensitivity of detection, several on-line sample preconcentration techniques such as sweeping have been developed.

  3. Affinity chromatography of phosphorylated proteins. (United States)

    Tchaga, Grigoriy S


    This chapter covers the use of immobilized metal ion affinity chromatography (IMAC) for enrichment of phosphorylated proteins. Some requirements for successful enrichment of these types of proteins are discussed. An experimental protocol and a set of application data are included to enable the scientist to obtain high-yield results in a very short time with pre-packed phospho-specific metal ion affinity resin (PMAC).

  4. Lagrangian description of nonlinear chromatography

    Institute of Scientific and Technical Information of China (English)

    LIANG Heng; LIU Xiaolong


    Under the framework of non-equilibrium thermodynamic separation theory (NTST), Local Lagrangian approach (LLA) was proposed to deal with the essential issues of the convection and diffusion (shock waves) phenomena in nonlinear chromatography with recursion equations based on the three basic theorems, Lagrangian description, continuity axiom and local equilibrium assumption (LEA). This approach remarkably distinguished from the system of contemporary chromatographic theories (Eulerian description-partial differential equations), and can felicitously match modern cybernetics.

  5. Lectin affinity chromatography of glycolipids

    Energy Technology Data Exchange (ETDEWEB)

    Torres, B.V.; Smith, D.F.


    Since glycolipids (GLs) are either insoluble or form mixed micelles in water, lectin affinity chromatography in aqueous systems has not been applied to their separation. They have overcome this problem by using tetrahydrofuran (THF) in the mobile phase during chromatography. Affinity columns prepared with the GalNAc-specific Helix pomatia agglutinin (HPA) and equilibrated in THF specifically bind the (/sup 3/H)oligosaccharide derived from Forssman GL indicating that the immobilized HPA retained its carbohydrate-binding specificity in this solvent. Intact Forssman GL was bound by the HPA-column equilibrated in THF and was specifically eluted with 0.1 mg/ml GalNAc in THF. Purification of the Forssman GL was achieved when a crude lipid extract of sheep erythrocyte membranes was applied to the HPA-column in THF. Non-specifically bound GLs were eluted from the column using a step gradient of aqueous buffer in THF, while the addition of GalNAc was required to elute the specifically bound GLs. Using this procedure the A-active GLs were purified from a crude lipid extract of type A human erythrocytes in a single chromatographic step. The use of solvents that maintain carbohydrate-binding specificity and lipid solubility will permit the application of affinity chromatography on immobilized carbohydrate-binding proteins to intact GLs.

  6. Entropy Best Paper Award 2015

    Directory of Open Access Journals (Sweden)

    Kevin H. Knuth


    Full Text Available We are pleased to announce the “Entropy Best Paper Award” for 2015. Nominations were selected by the Editor-in-Chief and designated Editorial Board Members from all the papers published in 2011. Reviews and research papers were evaluated separately. We gladly announce that the following three papers have won the Entropy Best Paper Award in 2015:[...

  7. Monitoring the synthesis of new pitches from coal tar and its fractions by chromatography and related techniques. (United States)

    Bermejo, J; Fernández, A L; Prada, V; Granda, M; Menéndez, R


    The aim of this paper is to study the applications of chromatography and related techniques in the transformation of coal-derived products into pitches for specific uses. Anthracene oil, tar and pitch were thermally treated in the presence of air (and sulfur in the case of anthracene oil) in order to cause the polymerization/condensation of their components. The evolution of the components of the parent materials during the treatments was monitored by gas chromatography-mass spectrometry, gas chromatography-atomic emission detection, probe mass spectrometry and size-exclusion chromatography. From the results obtained, possible mechanisms for the transformation of coal-derived products into new pitches were established.

  8. Nano-liquid chromatography applied to enantiomers separation. (United States)

    Fanali, Salvatore


    This paper presents the state of the art concerning the separation of chiral compounds by means of nano-liquid chromatography (nano-LC). The enantiomers' separation and determination are a subject of fundamental importance in various application fields such as pharmaceutical industry, biomedicine, food, agrochemical etc. Nano-LC is a miniaturized chromatographic technique offering some advantages over conventional ones such as low consumption of mobile phase, sample volume and amount of chiral stationary phase, reduced costs etc. This is reported in the first part of the paper illustrating the features of the nano-LC. In addition, chiral resolution methods are briefly illustrated. Some chiral selectors, used in high-performance liquid chromatography have also been applied in nano-LC including cyclodextrins, glycopeptide antibiotics, modified polysaccharides etc. This is discussed in the second part of the review. Finally some examples of the applications available in literature are reported.

  9. Application of coupled affinity-sizing chromatography for the detection of proteolyzed HSA-tagged proteins. (United States)

    London, Anne Serdakowski; Patel, Kunal; Quinn, Lisa; Lemmerer, Martin


    Coupled affinity liquid chromatography and size exclusion chromatography (ALC-SEC) is a technique that has been shown to successfully report product quality of proteins during cell expression and prior to the commencement of downstream processing chromatography steps. This method was applied to monitoring the degradation and subsequent partial remediation of a HSA-tagged protein which showed proteolysis, allowing for rapid cell line development to address this product quality dilemma. This paper outlines the novel application of this method for measuring and addressing protease-induced proteolysis.

  10. The Path of Carbon in Photosynthesis V. Paper Chromatography and Radioautography of the Products (United States)

    Benson, A. A.; Bassham, J. A.; Calvin, M.; Goodale, T. C.; Haas, V. A.; Stepka, W.


    Detailed procedure and results for the separation and identification of labeled carboxylic acids and phosphate esters, formed during photosynthesis in C{sup 14}O{sub 2}; the first observed product of CO{sub 2} assimilation during photosynthesis was isolated and shown to be phosphoglyceric acid; tracer use of P{sup 32} and C{sup 14}.

  11. Identification of Explosives from Porous Materials: Applications Using Reverse Phase High Performance Liquid Chromatography and Gas Chromatography (United States)

    Miller, C. J.; Elias, G.; Schmitt, N. C.; Rae, C.


    High performance liquid chromatography and gas chromatography techniques are well documented and widely used for the detection of trace explosives from organic solvents. These techniques were modified to identify and quantify explosives extracted from various materials taken from people who had recently handled explosives. Documented techniques were modified to specifically detect and quantify trace levels of the military explosives, RDX, TNT, and PETN from denim, colored flannel, vinyl, and canvas extracted in methanol and filtered using no additional sample cleanup of the sample extract prior to analysis. The filtered methanol extracts were injected directly into several different column types and analyzed by high performance liquid chromatography using ultraviolet detection and/or gas chromatography using electron capture detection. This paper describes general screening methods that were used to determine the presence of explosives (RDX, TNT, and PETN) in unknown samples of denim, colored flannel, vinyl and canvas in addition to techniques that have been optimized for quantification of each explosive from the substrate extracts.

  12. Pencil-drawn paper supported electrodes as simple electrochemical detectors for paper-based fluidic devices. (United States)

    Dossi, Nicolò; Toniolo, Rosanna; Pizzariello, Andrea; Impellizzieri, Flavia; Piccin, Evandro; Bontempelli, Gino


    A simple procedure for preparing inexpensive paper-based three-electrode electrochemical cells is described here. They consist of small circular pads of hydrophilic paper defined by hydrophobic barriers printed on paper with wax-based ink. The back face of these pads is insulated by thermally laminating a polyethylene layer and working, reference and counter electrodes are drawn on paper by using commercial pencil leads. At last, a controlled volume of sample containing a supporting electrolyte was laid to soak in paper channels. Their performance was evaluated by assaying these devices as both simple cells suitable for recording voltammograms on static samples and low-cost detectors for flowing systems. Voltammetric tests, conducted by using potassium hexacyanoferrate(II) as model prototype, were also exploited for identifying the brand and softness of graphite sticks enabling paper to be marked with lines displaying the best conductivity. By taking advantage of the satisfactory information thus gained, pencil drawn electrodes were tested as amperometric detectors for the separation of ascorbic acid and sunset yellow, which were chosen as prototype electroactive analytes because they are frequently present concomitantly in several food matrices, such as soft drinks and fruit juices. This separation was performed by planar thin layer chromatography conducted on microfluidic paper-based devices prepared by patterning on filter paper two longitudinal hydrophobic barriers, once again printed with wax-based ink. Factors affecting both separation and electrochemical detection were examined and optimised, with best performance achieved by using a 20 mM acetate running buffer (pH 4.5) and by applying a detection potential of 0.9 V. Under these optimum conditions, the target analytes could be separated and detected within 6 min. The recorded peaks were well separated and characterized by good repeatability and fairly good sensitivity, thus proving that this approach is

  13. Ion Exchange and Liquid Column Chromatography. (United States)

    Walton, Harold F.


    Emphasizes recent advances in principles and methodology in ion exchange and chromatography. Two tables list representative examples for inorganic ions and organic compounds. Cites 544 references. (CS)

  14. Evolution of the scientific paper

    Energy Technology Data Exchange (ETDEWEB)

    Harmon, J.E.


    The first papers reporting original research results in technical periodicals and proceedings appeared in the late 17th century. Since that time, the typical scientific paper has evolved from a fairly simple document, accessible to a general audience, to a much more complex one, aimed at a specialized audience. The purpose of this article is to give an overview of what the first scientific papers were like and how they evolved to their present form and style. To facilitate this discussion, the scientific paper`s development has arbitrarily been divided into four stages: the origin and formative years of the scientific paper (1665-1765), emergence of scientific papers written for specialized publications (1765-1865), development of the modem scientific paper (1865-1965), and hyperspecialization and computerization of the modem scientific paper (1965-?).

  15. Evolution of the scientific paper

    Energy Technology Data Exchange (ETDEWEB)

    Harmon, J.E.


    The first papers reporting original research results in technical periodicals and proceedings appeared in the late 17th century. Since that time, the typical scientific paper has evolved from a fairly simple document, accessible to a general audience, to a much more complex one, aimed at a specialized audience. The purpose of this article is to give an overview of what the first scientific papers were like and how they evolved to their present form and style. To facilitate this discussion, the scientific paper's development has arbitrarily been divided into four stages: the origin and formative years of the scientific paper (1665-1765), emergence of scientific papers written for specialized publications (1765-1865), development of the modem scientific paper (1865-1965), and hyperspecialization and computerization of the modem scientific paper (1965- ).

  16. Business Plan: Paper Recycling Plant


    Ali, Muhammad; Askari, Sana; Salman, Muhammad; Askari, Sheba


    This Business Plan was written for Business Plan competition organized by Ministry of Youth Affairs Government of Pakistan. It explains the paper recycling business, its pros and cons, cost of paper recycling, plant options and feasibility.

  17. Recycling of Paper and Cardboard

    DEFF Research Database (Denmark)

    Christensen, Thomas Højlund; Damgaard, Anders


    Paper and cardboard are produced from pulp derived from plant fibers, primarily wood. Paper and cardboard is used for many different products, such as for packaging material, newsprint and advertisements. Most of these products have very short lifetimes and thus constitute a major fraction of most...... and cardboard are produced and how waste paper is recycled in the industry. Quality requirements and use of recycled products are discussed, as are the resource and environmental issues of paper recycling....

  18. Addenda to the Preceding Paper (United States)

    Bhatnagar, Rajat; Finn, Robert


    This work contains largely afterthoughts, relating to the paper immediately preceding it. We correlate and interpret our contributions in that paper, relative to those of an earlier publication by Aspley, He and McCuan. We propose specific laboratory experiments, suggested by formal predictions of those two papers.

  19. Molecules Best Paper Award 2013. (United States)

    McPhee, Derek J


    Molecules has started to institute a "Best Paper" award to recognize the most outstanding papers in the area of natural products, medicinal chemistry and molecular diversity published in Molecules. We are pleased to announce the second "Molecules Best Paper Award" for 2013.

  20. Entropy Best Paper Award 2014

    Directory of Open Access Journals (Sweden)

    Kevin H. Knuth


    Full Text Available In 2013, Entropy instituted the “Best Paper” award to recognize outstanding papers in the area of entropy and information studies published in Entropy [1]. We are pleased to announce the “Entropy Best Paper Award” for 2014. Nominations were selected by the Editor-in-Chief and designated Editorial Board Members from all the papers published in 2010.

  1. Analysis of polycyclic aromatic hydrocarbons by supercritical fluid chromatography (SFC)

    Energy Technology Data Exchange (ETDEWEB)

    Leselier, E. [Institut Universitaire de Technologie, 91 - Orsay (France). Letiam


    Usually, elution gradient high performance liquid chromatography using polymeric octadecyl bonded phases is chosen for this kind of separation. Due to the properties of carbon dioxide, low viscosity, high eluting power, separations obtained by supercritical fluid chromatography (SFC) are generally faster than by liquid solvents. This paper reports the study of the PAH separation by SFC. The effects of the nature and percentage of modifiers, pressure, temperature and the choice of the stationary phase (mono or poly-functional, high or low bonded density) are discussed. Results show that coupling two different columns is needed to reach the complete separation of the 16 PAHs requires by the standard of the Environmental Protection Agency (EPA 610). The separation is achieved in 25 minutes with a linear acetonitrile/CO{sub 2} mobile phase gradient. Applied to the analysis of soil extracts, this analytical technique is enable to separate numerous other compounds than standard PAHs. (author) 17 refs.

  2. An unusual case of xylophagia (paper-eating

    Directory of Open Access Journals (Sweden)

    Mahesh Gowda


    Full Text Available Xylophagia is a condition involving the consumption of paper and form of eating disorder known as pica. Pica is an unusual craving for ingestion of either edible or inedible substances. Inhalants are volatile substances, which produce chemical vapors that can be inhaled to induce a psycho-active or mind altering effect. Although, pica is not linked to solvent abuse, here we report an adolescent case of paper-eating with solvent dependence.

  3. Entropy Best Paper Award 2013

    Directory of Open Access Journals (Sweden)

    Kevin H. Knuth


    Full Text Available The journal Entropy is initiating a “Best Paper” award to recognize outstanding papers in the area of entropy and information studies published in Entropy. We are pleased to announce the first “Entropy Best Paper Award” for 2013. Nominations were selected by the Editor-in-Chief and selected Editorial Board Members from all the papers published in 2009 and evaluated by the Entropy Best Paper Award Committee. Reviews and articles were evaluated separately. A first prize is awarded to the selected review paper, and a first and second prize is awarded to the top two selected research articles.

  4. On Constructing Seminal Paper Genealogy. (United States)

    Bae, Duck-Ho; Hwang, Se-Mi; Kim, Sang-Wook; Faloutsos, Christos


    Let us consider that someone is starting a research on a topic that is unfamiliar to them. Which seminal papers have influenced the topic the most? What is the genealogy of the seminal papers in this topic? These are the questions that they can raise, which we try to answer in this paper. First, we propose an algorithm that finds a set of seminal papers on a given topic. We also address the performance and scalability issues of this sophisticated algorithm. Next, we discuss the measures to decide how much a paper is influenced by another paper. Then, we propose an algorithm that constructs a genealogy of the seminal papers by using the influence measure and citation information. Finally, through extensive experiments with a large volume of a real-world academic literature data, we show the effectiveness and efficiency of our approach.

  5. Asian-Pacific Papers. Occasional Papers Number 10. (United States)

    McCarthy, Brian, Ed.

    Sixteen papers are presented. Topics covered include language teaching, discourse analysis, code switching, phonetics, language and cultural identity, and descriptive and comparative studies. All presenters were from the Asia-Pacific area of the world. Papers include: "The Baba Malay Lexicon: Hokkien Loanwords in Baba Malay" (Anne…

  6. Identification of Explosives from Porous Materials: Applications Using Reverse Phase High Performance Liquid Chromatography and Gas Chromatography

    Energy Technology Data Exchange (ETDEWEB)

    C.J. Miller; G. Elias; N.C. Schmitt; C. Rae


    High performance liquid chromatography and gas chromatography techniques are well documented and widely used for the detection of trace explosives from organic solvents. These techniques were modified to specifically identify and quantify explosives extracted from various materials taken from people who had recently handled explosives. Documented techniques were modified to specifically detect and quantify RDX, TNT, and PETN from denim, colored flannel, vinyl, and canvas extracted in methanol using no sample cleanup prior to analysis. The methanol extracts were injected directly into several different column types and analyzed by HPLC-UV and/or GC-ECD. This paper describes general screening methods that were used to determine the presence of explosives in unknown samples and techniques that have been optimized for quantification of each explosive from the substrate extracts.

  7. Liquid phase chromatography on microchips. (United States)

    Kutter, Jörg P


    Over the past twenty years, the field of microfluidics has emerged providing one of the main enabling technologies to realize miniaturized chemical analysis systems, often referred to as micro-Total Analysis Systems (uTAS), or, more generally, Lab-on-a-Chip Systems (LOC) [1,2]. While microfluidics was driven forward a lot from the engineering side, especially with respect to ink jet and dispensing technology, the initial push and interest from the analytical chemistry community was through the desire to develop miniaturized sensors, detectors, and, very early on, separation systems. The initial almost explosive development of, in particular, chromatographic separation systems on microchips, has, however, slowed down in recent years. This review takes a closer, critical look at how liquid phase chromatography has been implemented in miniaturized formats over the past several years, what is important to keep in mind when developing or working with separations in a miniaturized format, and what challenges and pitfalls remain.

  8. Polymer nanoparticles in electrokinetic chromatography (United States)

    Hyslop, Jesse Samuel

    This dissertation reports the mobility, methylene selectivity, efficiency, linear solvation relationship (LSER) parameters, and practical chromatographic performance of a large set of NP PSPs and develops the first empirical relationships between NP architecture and chromatographic performance of NP PSPs in EKC. It is found that under typical EKC conditions ionic block chemistry has little effect on performance for 5-10 mer blocks. Solute-PSP interactions appear to be localized on the hydrophobic block of the copolymer with the length of alkyl chains on the hydrophobic block controlling the cohesively and hydrophobicity of the PSP. Small (100 nm) NP PSPs with small hydrophobic NP PSPs providing the best overall performance. This work provides the fundamental understanding of the behavior of RAFT polymerized NP PSPs essential for their further development and application in electrokinetic chromatography. (Abstract shortened by ProQuest.).

  9. Detection in superheated water chromatography

    Energy Technology Data Exchange (ETDEWEB)

    Chienthavorn, O


    Superheated water has been used successfully as an eluent in liquid chromatography and has been coupled to various modes of detection, ultraviolet (UV), fluorescence, and nuclear magnetic resonance spectroscopy (NMR) and mass spectrometry (MS). A number of compounds were examined on poly(styrene-divinylbenzene) (PS-DVB), polybutadiene (PBD), and octadecylsilyl bonded silica (ODS) column with isothermal and temperature programmes. The PS-DVB column was mostly used throughout the project as it was the most stable. Not only pure water could serve as superheated water mobile phase; inorganic buffered water and ion-pairing reagent with a concentration of 1-3 mM of the buffer and reagent were also exploited. It was shown that the pH could be controlled during the separation without salt precipitation and the separations followed a conventional reversed-phase HPLC method. Results from fluorescence detection showed good separation of a series of vitamins, such as pyridoxine, riboflavin, thiamine, and some analgesics. The relationship of riboflavin using the detection was linear and the detection limit was seven times higher than that of a conventional method. Simultaneous separation and identification using superheated water chromatography-NMR was demonstrated. With using a stop flow method, NMR spectra of model drugs, namely barbiturates, paracetamol, caffeine and phenacetin were obtained and the results agreed with reference spectra, confirming a perfect separation. A demonstration to obtain COSY spectrum of salicylamide was also performed. The method was expanded to the coupling of superheated water LC to NMR-MS. Results from the hyphenated detection method showed that deuteration and degradation happened in the superheated water conditions. The methyl group hydrogens of pyrimidine ring of sulfonamide and thiamine were exchanged with deuterium. Thiamine was decomposed to 4-methyl-5-thiazoleethanol and both were deuterated under the conditions. (author)

  10. Sensors Best Paper Award 2015

    Directory of Open Access Journals (Sweden)

    Vittorio M.N. Passaro


    Full Text Available Since 2011, an annual award system was instituted to recognize outstanding Sensors papers that are related to sensing technologies and applications and meet the aims, scope and high standards of this journal [1–4]. This year, the winners were chosen by the Section Editor-in-Chiefs of Sensors from among all the papers published in 2011 to track citations. Reviews and full research articles were considered separately. We gladly announce that the following eight papers were awarded the Sensors Best Paper Award in 2015.[...

  11. [Project Social Studies. Discipline Papers. (United States)

    Minnesota Univ., Minneapolis. Project Social Studies Curriculum Center.

    The special papers provide a definition, delineate the scope, present a conceptual framework, and identify the method of inquiry and some techniques used for explaining the body of knowledge for each of six disciplines. The background papers to Project Social Studies are: 1) "Sociology" by Caroline Rose; 2) "The Study of Geography" by Fredrick R.…

  12. Working Paper on Social capital

    DEFF Research Database (Denmark)

    Lassen Hanan, Anne


    This paper outlines the major schools within social capital theory. Contemporary authors such as Coleman, Putnam and Bourdieu are elaborated on. The paper also presents a non-exhaustive review on studies of social capital. Furthermore, a criticial discussion on social capital is reviewed, before...

  13. SQA specimen papers 2013, national 5, physics and model papers

    CERN Document Server



    Practise for your exam on the official National 5 specimen paper from the Scottish Qualifications Authority . This book also includes additional model papers and extra revision guidance, making it an essential purchase for any student. - Discover how to get your best grade with answers checked by senior examiners. - Prepare for your exams with study skills guidance sections. - Gain vital extra marks and avoid common mistakes with examiner tips

  14. Principles of Micellar Electrokinetic Capillary Chromatography Applied in Pharmaceutical Analysis

    Directory of Open Access Journals (Sweden)

    Árpád Gyéresi


    Full Text Available Since its introduction capillary electrophoresis has shown great potential in areas where electrophoretic techniques have rarely been used before, including here the analysis of pharmaceutical substances. The large majority of pharmaceutical substances are neutral from electrophoretic point of view, consequently separations by the classic capillary zone electrophoresis; where separation is based on the differences between the own electrophoretic mobilities of the analytes; are hard to achieve. Micellar electrokinetic capillary chromatography, a hybrid method that combines chromatographic and electrophoretic separation principles, extends the applicability of capillary electrophoretic methods to neutral analytes. In micellar electrokinetic capillary chromatography, surfactants are added to the buffer solution in concentration above their critical micellar concentrations, consequently micelles are formed; micelles that undergo electrophoretic migration like any other charged particle. The separation is based on the differential partitioning of an analyte between the two-phase system: the mobile aqueous phase and micellar pseudostationary phase. The present paper aims to summarize the basic aspects regarding separation principles and practical applications of micellar electrokinetic capillary chromatography, with particular attention to those relevant in pharmaceutical analysis.

  15. Principles of micellar electrokinetic capillary chromatography applied in pharmaceutical analysis. (United States)

    Hancu, Gabriel; Simon, Brigitta; Rusu, Aura; Mircia, Eleonora; Gyéresi, Arpád


    Since its introduction capillary electrophoresis has shown great potential in areas where electrophoretic techniques have rarely been used before, including here the analysis of pharmaceutical substances. The large majority of pharmaceutical substances are neutral from electrophoretic point of view, consequently separations by the classic capillary zone electrophoresis; where separation is based on the differences between the own electrophoretic mobilities of the analytes; are hard to achieve. Micellar electrokinetic capillary chromatography, a hybrid method that combines chromatographic and electrophoretic separation principles, extends the applicability of capillary electrophoretic methods to neutral analytes. In micellar electrokinetic capillary chromatography, surfactants are added to the buffer solution in concentration above their critical micellar concentrations, consequently micelles are formed; micelles that undergo electrophoretic migration like any other charged particle. The separation is based on the differential partitioning of an analyte between the two-phase system: the mobile aqueous phase and micellar pseudostationary phase. The present paper aims to summarize the basic aspects regarding separation principles and practical applications of micellar electrokinetic capillary chromatography, with particular attention to those relevant in pharmaceutical analysis.

  16. Selected papers in hydrologic sciences (United States)

    A collection of short topical papers providing significant results of hydrologic studies by the U.S. Geological Survey, Department of the Interior, has been published as “Selected Papers in the Hydrologic Sciences, Volume 1” (Water-Supply Paper 2262). Edited by Eric L. Meyer, “Selected Papers in the Hydrologic Sciences“ is a new journal-type publication that will be a part of the existing U.S. Geological Survey Water-Supply Paper series. The “journal” is aimed at meeting the widespread public and professional interest of the hydrologic community in timely results from hydrologic studies derived from federal research programs, federal-state cooperative programs, and some work done on behalf of other federal agencies.This first volume, comprising eight papers, addresses a broad array of topics covering sediment chemistry, pesticides, toxic metals, and streamflow characteristics. Included are papers on a technique to measure oxygen in the root zone of saturated and unsaturated soils; measurement of surface runoff and collection of sediment samples from small areas; organic carbon in volcanic ash from Mount St. Helens, Washington; organochlorine pesticide and polychlorinated biphenyl in the Schuylkill River, Pennsylvania; interference of cadmium carbonate precipitation in the determination of cation exchange separation factors; confidence limtis for determining concentrations of tracer particles in sediment samples; determination of aquatic humic substances in natural water; and use of channel cross-section properties for estimating streamflow characteristics.

  17. Diffusive dynamics on paper matrix (United States)

    Chaudhury, Kaustav; Kar, Shantimoy; Chakraborty, Suman


    Writing with ink on a paper and the rapid diagnostics of diseases using paper cartridge, despite their remarkable diversities from application perspective, both involve the motion of a liquid from a source on a porous hydrophilic substrate. Here we bring out a generalization in the pertinent dynamics by appealing to the concerned ensemble-averaged transport with reference to the underlying molecular picture. Our results reveal that notwithstanding the associated complexities and diversities, the resultant liquid transport characteristics on a paper matrix, in a wide variety of applications, resemble universal diffusive dynamics. Agreement with experimental results from diversified applications is generic and validates our unified theory.

  18. Quantum interaction. Revised selected papers

    Energy Technology Data Exchange (ETDEWEB)

    Song, Dawei; Zhang, Peng; Wang, Lei [Aberdeen Univ. (United Kingdom). School of Computing; Melucci, Massimo [Padua Univ., Padova (Italy). Dept. of Information Engineering; Frommholz, Ingo [Bedfordshire Univ. (United Kingdom); Arafat, Sachi (eds.) [Glasgow Univ. (United Kingdom). School of Computing Science


    This book constitutes the thoroughly refereed post-conference proceedings of the 5th International Symposium on Quantum Interaction, QI 2011, held in Aberdeen, UK, in June 2011. The 26 revised full papers and 6 revised poster papers, presented together with 1 tutorial and 1 invited talk were carefully reviewed and selected from numerous submissions during two rounds of reviewing and improvement. The papers show the cross-disciplinary nature of quantum interaction covering topics such as computation, cognition, mechanics, social interaction, semantic space and information representation and retrieval. (orig.)

  19. "Paper Cut Lady" Ku Shulan

    Institute of Scientific and Technical Information of China (English)


    WHEN the people in Xunyi County of Shaanxi Province talk about the traditional paper cut, they always speak of a "paper cut lady" Ku Shulan. Her works have been shown at the Xi’an Artists’ Gallery, Beijing China Art Gallery and Exhibition Hall of Central Academy of Fine Arts. Almost seventy years old, Ku Shulan is an ordinary country lady, and her artistic achievements were closely linked with her mother countryside. The traditional paper cut created and developed in Xunyi County, has a simple and bold style of Northern Shaanxi, and an exquisitely

  20. Another Day, Another White Paper (United States)

    Tomlinson, Sally


    This article argues that the proposals in the 2005 White Paper can be largely explained by a New Labour emphasis on "meritocracy" merging with a right-wing belief in education as a means of creating an hierarchical society.

  1. Writing a clinical research paper

    Directory of Open Access Journals (Sweden)

    Ajao Oluwole


    Full Text Available A well-known unwritten law in institutions of higher learning is that of "Publish or perish". The duties of a University teacher, in order of priority are teaching, research and service. Reasons for writing clinical research papers are to get promoted, to get research grants and to make known, one′s findings in order to improve patients′ care. Writing papers is also a means of delivering continuous education, therefore publication is essential for any one pursuing an academic career. Research papers can be in the form of case reports, retrospective studies, prospective studies and laboratory or animal research. Two popular formats of writing papers are: The Vancouver Style and the Harvard System.

  2. All-printed paper memory

    KAUST Repository

    He, Jr-Hau


    All-printed paper-based substrate memory devices are described. In an embodiment, a paper-based memory device is prepared by coating one or more areas of a paper substrate with a conductor material such as a carbon paste, to form a first electrode of a memory, depositing a layer of insulator material, such as titanium dioxide, over one or more areas of the conductor material, and depositing a layer of metal over one or more areas of the insulator material to form a second electrode of the memory. In an embodiment, the device can further include diodes printed between the insulator material and the second electrode, and the first electrode and the second electrodes can be formed as a crossbar structure to provide a WORM memory. The various layers and the diodes can be printed onto the paper substrate by, for example, an ink jet printer.

  3. Sensors Best Paper Award 2014

    Directory of Open Access Journals (Sweden)

    Vittorio M. N. Passaro


    Full Text Available In 2011, an annual award system was instituted to recognize outstanding Sensors papers that are related to sensing technologies and applications and meet the aims, scope and high standards of this journal [1–3]. This year, nominations were made by the Section Editor-in-Chiefs of Sensors from among all the papers published in 2010 to track citations. Reviews and full research articles were considered separately.

  4. All-printed paper memory

    KAUST Repository

    Lien, Derhsien


    We report the memory device on paper by means of an all-printing approach. Using a sequence of inkjet and screen-printing techniques, a simple metal-insulator-metal device structure is fabricated on paper as a resistive random access memory with a potential to reach gigabyte capacities on an A4 paper. The printed-paper-based memory devices (PPMDs) exhibit reproducible switching endurance, reliable retention, tunable memory window, and the capability to operate under extreme bending conditions. In addition, the PBMD can be labeled on electronics or living objects for multifunctional, wearable, on-skin, and biocompatible applications. The disposability and the high-security data storage of the paper-based memory are also demonstrated to show the ease of data handling, which are not achievable for regular silicon-based electronic devices. We envision that the PPMDs manufactured by this cost-effective and time-efficient all-printing approach would be a key electronic component to fully activate a paper-based circuit and can be directly implemented in medical biosensors, multifunctional devices, and self-powered systems. © 2014 American Chemical Society.

  5. Applications of hydrophilic interaction chromatography to amino acids, peptides, and proteins. (United States)

    Periat, Aurélie; Krull, Ira S; Guillarme, Davy


    This review summarizes the recent advances in the analysis of amino acids, peptides, and proteins using hydrophilic interaction chromatography. Various reports demonstrate the successful analysis of amino acids under such conditions. However, a baseline resolution of the 20 natural amino acids has not yet been published and for this reason, there is often a need to use mass spectrometry for detection to further improve selectivity. Hydrophilic interaction chromatography is also recognized as a powerful technique for peptide analysis, and there are a lot of papers showing its applicability for proteomic applications (peptide mapping). It is expected that its use for peptide mapping will continue to grow in the future, particularly because this analytical strategy can be combined with reversed-phase liquid chromatography, in a two-dimensional setup, to reach very high resolving power. Finally, the interest in hydrophilic interaction chromatography for intact proteins analysis is less evident due to possible solubility issues and a lack of suitable hydrophilic interaction chromatography stationary phases. To date, it has been successfully employed only for the characterization of membrane proteins, histones, and the separation of glycosylated isoforms of an intact glycoprotein. From our point of view, the number of hydrophilic interaction chromatography columns compatible with intact proteins (higher upper temperature limit, large pore size, etc.) is still too limited.

  6. Papers in Semantics. Working Papers in Linguistics No. 49. (United States)

    Yoon, Jae-Hak, Ed.; Kathol, Andreas, Ed.


    Papers on semantic theory and research include: "Presupposition, Congruence, and Adverbs of Quantification" (Mike Calcagno); "A Unified Account of '(Ta)myen'-Conditionals in Korean" (Chan Chung); "Spanish 'imperfecto' and 'preterito': Truth Conditions and Aktionsart Effects in a Situation Semantics" (Alicia Cipria,…

  7. Papers in Phonology. Working Papers in Linguistics No. 41. (United States)

    Hume, Elizabeth, Ed.

    Six working papers on phonology, primarily concerning less commonly taught languages, are presented are in this volume. Titles include: "Non-Uniqueness Condition and the Segmentation of the Chinese Syllable" (Benjamin Ao); "Theoretical Consequences of Metathesis in Maltese" (Elizabeth Hume); "Cs and Vs or Moras: The Case…

  8. The Chromatography of Leaves and Inks. (United States)

    Chemecology, 1997


    Describes the use of a simple process known as chromatography to separate and observe the color pigments in leaves, inks, and other materials. Provides some historical background and detailed procedures. (DDR)

  9. Stationary phases for superheated water chromatography

    CERN Document Server

    Saha, S


    This project focused on the comparison of conventional liquid chromatography and superheated water chromatography. It examined the differences in efficiency and retention of a range of different stationary phases. Alkyl aryl ketones and eight aromatic compounds were separated on PBD-zirconia, Xterra RP 18, Luna C sub 1 sub 8 (2) and Oasis HLB columns using conventional LC and superheated water chromatography system. The retention indices were determined in the different eluents. On changing the organic component of the eluent from methanol to acetonitrile to superheated water considerable improvements were found in the peak shapes and column efficiencies on the PBD-zirconia and Oasis HLB columns. PS-DVB, PBD-zirconia and Xterra RP 18 columns have been used in efficiency studies. It was found that simply elevating the column temperature did not increase the efficiency of a separation in superheated water chromatography. The efficiency depended on flow rate, injection volume and also mobile phase preheating sys...

  10. Diagonal chromatography to study plant protein modifications

    NARCIS (Netherlands)

    Walton, Alan; Tsiatsiani, Liana; Jacques, Silke; Stes, Elisabeth; Messens, Joris; Van Breusegem, Frank; Goormachtig, Sofie; Gevaert, Kris


    An interesting asset of diagonal chromatography, which we have introduced for contemporary proteome research, is its high versatility concerning proteomic applications. Indeed, the peptide modification or sorting step that is required between consecutive peptide separations can easily be altered and

  11. High-Performance Liquid Chromatography: An Overview


    Tandia N; Singh SK1; Kumar N; Singh S


    Chromatography is considered extremely powerful separation technique for variety of samples. Thecommon feature of all these techniques is that the different components in a sample mixture aredistributed between two phases, one of which remains stationary while the other the mobile phase, runsthrough the interstices or over the surface of the fixed phase. The movement of the mobile phase resultsin differential migration of the sample components. High performance thin layer chromatography is an...

  12. Rabi N. Bhattacharya selected papers

    CERN Document Server

    Waymire, Edward


    This volume presents some of the most influential papers published by Rabi N. Bhattacharya, along with commentaries from international experts, demonstrating his knowledge, insight, and influence in the field of probability and its applications. For more than three decades, Bhattacharya has made significant contributions in areas ranging from theoretical statistics via analytical probability theory, Markov processes, and random dynamics to applied topics in statistics, economics, and geophysics. Selected reprints of Bhattacharya’s papers are divided into three sections: Modes of Approximation, Large Times for Markov Processes, and Stochastic Foundations in Applied Sciences. The accompanying articles by the contributing authors not only help to position his work in the context of other achievements, but also provide a unique assessment of the state of their individual fields, both historically and for the next generation of researchers. Rabi N. Bhattacharya: Selected Papers will be a valuable resource for yo...

  13. Active paper for active learning

    Directory of Open Access Journals (Sweden)

    Heather Brown


    Full Text Available Paper documents have great advantages in readability, portability and familiarity, but are necessarily static and slow to update. Much recent research has concentrated on the dynamic demonstrations, immediate feedback, and easy updating that can be provided by electronic teaching material. Although an increasing number of teaching packages make use of both paper and electronic documents, the two are typically accessed by completely separate interfaces. We have been taking a different approach and investigating the use of a DigitalDesk (Wellner, 1991; Wellner, 1993 as a means of integrating normal paper teaching material with electronic versions of the same material. Many printed books also exist in electronic form, and our goal is to allow these books to be used as natural interfaces to any additional information that may be present in the electronic version.

  14. Selected papers from ESSDERC 2014 (United States)

    Bez, Roberto; Meneghesso, Gaudenzio; Pavan, Paolo; Zanoni, Enrico


    This special issue of Solid State Electronics includes 28 paper selected from the best presentations given at the 44th European Solid-State Device Research Conference (ESSDERC 2014, September 22-26, 2014 - Venice, Italy). These papers cover different topics in the research on solid-state devices. These topics are used also to organize the conference presentations in 7 tracks: Advanced CMOS: Devices, Process and Integration; Microwave, Opto and Power Solid-State Devices; Modeling and Simulation; Characterization, Reliability and Yield; Advanced and Emerging Memories; MEMS, NEMS, Bio-sensors and Display Technologies; Emerging non-CMOS Devices and Technologies.

  15. Street Papers, Work, and Begging

    DEFF Research Database (Denmark)

    Cockburn, Patrick Joseph


    Street papers are publications produced specifically for sale by the homeless and other vulnerable people in many countries around the world. Their social status is, however, often conspicuously unstable: ‘Get a job!’ has been reported as a common insult addressed to vendors, and street paper...... organisations have responded with their own rhetoric and strategies that aim at disrupting any analogy with begging. The present analysis frames these rhetorical confrontations as a struggle over economic legitimacy, highlighting some of the ways in which social actors build and sever the normatively...

  16. Methane from waste containing paper

    Energy Technology Data Exchange (ETDEWEB)


    Waste solids containing paper are biologically treated in a system by: fermentation with lactobacilli, separation of the solids, ion exchange of the supernatant from the separation, anaerobic digestion of the ion-exchanged liquor, separation of a liquor from the fermentation, and digestion of the liquor. Thus, a municipal waste containing paper and water was inoculated with Aspergillus niger and lactobacilli for 2 days; the mixture was anaerobically treated and centrifuged; the clear liquor was ion exchanged; and the solid waste was filter pressed. The filter cake was treated with Trichoderma nigricaus and filtered. The filtrate and the ion-exchanged liquor were digested for CH/sub 4/ production.

  17. Selected papers on optomechanical design (United States)

    O'Shea, Donald C.

    The papers included in this volume deal with a variety of topics in optical and optoelectronic science, engineering, and technology under the following headings: design, materials, tolerancing and specification, mounting, mechanical analysis, thermal analysis, stabilization, baffling, assembly and alignment, and scanning. Particular topics discussed include selection of materials and processes for metal optics, trends and limits in the production of optical elements and optical systems, aerospace mounts for down-to-earth optics, and thermal effects in optical systems. Papers are also presented on integrating Nd:YAG lasers into optical systems, line-of-sight steering and stabilization, and motors and control systems for rotating mirror deflectors.

  18. New criteria for the characterization of traditional East Asian papers. (United States)

    Avataneo, Chiara; Sablier, Michel


    We report a pyrolysis-gas chromatography/mass spectrometry (Py-GC/MS) method capable of analyzing traditional East Asian papers. The method proposed is based on rapid and easy single step Py-GC/MS analysis that can be carried out with a minimum amount of matter, in the few microgram range. Three reference papers manufactured from kozo (Broussonetia kazinoki Siebold & Zucc.), mitsumata (Edgeworthia chrysantha Lindl.), and gampi (Wikstroemia sikokiana Franch. & Sav.) with the traditional hand paper making processes were examined. The method allows discrimination between terpenic and steroid compounds, which were revealed as chemical markers of origin of the plant fibers. Each paper investigated was found to have characteristic pyrolysis fingerprints that were unique to the traditional handmade paper, demonstrating the potential for differentiation of these biochemical components of fiber plants on East Asian papers towards identification and conservation of cultural heritage. The investigation on Py-GC/MS was extended to liquid extraction followed by GC/MS analysis to characterize the biochemical components of fiber plants. The main contribution of this study is to provide molecular criteria for discriminating plant species used for traditional East Asian hand papermaking. Py-GC/MS complements efficiently microscope identification especially for adverse cases. A case study of archaeological Chinese paper painting artefacts was thereafter successfully investigated to address informative potential and efficiency of the criteria of identification on ancient and degraded East Asian paperworks.

  19. Getting rid of paper pushing. (United States)

    Wyatt, C


    A hospital in Tacoma, Wash., is taking several steps toward streamlining its business office functions. For example, the hospital is transmitting 90% of its claims electronically and has automated the posting of remittance advice and the billing of Medicare secondary payers. "Eventually we'll have a paperless system; we won't push paper back and forth," the hospital's patient accounts manager says.

  20. Overview paper on nuclear power

    Energy Technology Data Exchange (ETDEWEB)

    Spiewak, I.; Cope, D.F.


    This paper was prepared as an input to ORNL's Strategic Planning Activity, ORNL National Energy Perspective (ONEP). It is intended to provide historical background on nuclear power, an analysis of the mission of nuclear power, a discussion of the issues, the technology choices, and the suggestion of a strategy for encouraging further growth of nuclear power.

  1. Educational Choice. A Background Paper. (United States)

    Quality Education for Minorities Network, Washington, DC.

    This paper addresses school choice, one proposal to address parental involvement concerns, focusing on historical background, definitions, rationale for advocating choice, implementation strategies, and implications for minorities and low-income families. In the past, transfer payment programs such as tuition tax credits and vouchers were…

  2. Scientific papers: A new paradigm (United States)

    Reid, George C.

    The problem of how to organize and write a scientific paper is a very basic one for most of us. A scientific paper is, after all, the only tangible product of a research scientist and, like all products, will be a failure if not marketed properly to reach its potential buyers. I think that a lack of attention to this “marketing and sales” aspect of research is a serious fault in our community, by which I mean those of us who publish in AGU journals.The potential audience for a scientific paper can be divided roughly into three distinct categories. The first group is usually rather small in number, consisting of fellow scientists working in a very closely related field, and to whom the details of the work are of major importance. The second group is also fellow scientists, but their interest is less sharply focused, and they are concerned with the broad outlines of the work and essential results. The third group is the sponsors and the people who actually pay for the work, whose interest in the details is minimal and they, sadly enough, are often concerned only with the fact that a paper has been published rather than its content.

  3. A New Liquid Chromatography-Tandem Mass Spectrometry Method for Determination of Bisoprolol in Human Plasma Samples


    Gabriela Peste; Nela Bibire; Mihai Apostu; Aurel Vlase; Corneliu Oniscu


    Liquid chromatography (LC) coupled with mass spectrometry (MS) detection is one of the most powerful analytical tools for organic compound analysis. The advantages of using LC/MS methods over HPLC methods include: selectivity, chromatographic integrity, peak assignment, structural information, and rapid method development. In this paper, a new liquid chromatography-tandem mass spectrometry (LC-MS/MS) method has been developed and validated for the determination of bisoprolol in human plasma s...

  4. Analysis of paper machine process waters; Paperikoneen prosessivesianalytiikka - MPKT 09

    Energy Technology Data Exchange (ETDEWEB)

    Knuutinen, J.; Alen, R.; Harjula, P.; Kilpinen, J.; Pallonen, R.; Jurvela, V.


    The closure of paper machine circuits demands a better knowledge of the chemical structures and behaviour of organic compounds in pulp mill process waters. Nonionic or negatively charged detrimental substances (anionic trash) which will eventually cause runnability. Paper quality problems are of special interest. The main purpose of the project was to develop routine `fingerprint` analytical procedures to study various process waters. Our major interest was focused on low molecular weight carboxylic acids, carbohydrates and lignin based material. The `fingerprints` (chromatograms and electropherograms) can be used to differentiate various process waters or to find out changes between the composition of organic compounds in various stages of the papermaking process. Until now the most characteristic `fingerprints` were obtained by capillary zone electrophoresis (CZE) and by pyrolysis - gas chromatography - mass spectrometry (Py-GC/MS). Examples of using these techniques are briefly discussed. (orig.)

  5. COINCO Strategy 2025 - Discussion Paper

    DEFF Research Database (Denmark)

    Jespersen, Per Homann; Jensen, Anne; Stroschein, Christoph;

     The regions and cities in the COINCO-corridor Oslo-Göteborg-Malmö-Copenhagen-Berlin have worked out a strategy proposal which is presented in this discussion paper. Behind the strategy is a political will to utilize mutual strengths and together become a leading player in a globalized world, based...... as in and out of the corridor. Similarly an improved network for freight transport could be obtained by improving the rail connections between the terminals where the sea, road and rail transport systems connect. This paper presents a strategy proposal - the partners behind it are looking forward to have...... on common cultural, social and environmental values. The strategy comprises of a vision and more detailed aims and actions within three different areas: Corridor infrastructure, Innovation and Cooperation. In this way, the COINCO partners want to establish a political platform for transborder collaboration...

  6. Paper mechanisms for sonic interaction

    DEFF Research Database (Denmark)

    Delle Monache, Stefano; Rocchesso, Davide; Qi, Ji


    Introducing continuous sonic interaction in augmented pop-up books enhances the expressive and performative qualities of movables, making the whole narrative experience more engaging and personal. The SaMPL Spring School on Sounding Popables explored the specific topic of paper-driven sonic narra...... narratives. Working groups produced several sketches of sonic interactions with movables. The most significant sketches of sounding popables are presented and analyzed.......Introducing continuous sonic interaction in augmented pop-up books enhances the expressive and performative qualities of movables, making the whole narrative experience more engaging and personal. The SaMPL Spring School on Sounding Popables explored the specific topic of paper-driven sonic...

  7. Line Creep in Paper Peeling

    Directory of Open Access Journals (Sweden)

    Rosti J.


    Full Text Available We have studied experimentally the dynamics of the separation of a sheet of paper into two halves in a peeling configuration. The experimental setup consists of a peeling device, where a fracture front is driven along the plane of the paper, with a constant force. The theoretical picture is how an elastic line interacts with a random landscape of fracture toughness. We compare the results with theoretical simulations in several aspects. One recent finding concerns the autocorrelation function of the average front position. The data from the experiments produces so-called cusps or singularities in the correlation function, as predicted by the functional renormalization group theory for elastic lines. Comparisons with simulations with either a short range or a long range elastic kernel demonstrate that the latter agrees with the experimental observations, as expected.

  8. Simultaneous determination of seven flavonoids in Epimedium by liquid chromatography-tandem mass spectrometry method

    Institute of Scientific and Technical Information of China (English)

    Cai Sheng Wu; Bao Lin Guo; Yu Xin Sheng; Jin Lan Zhang


    In this paper, a sensitive and specific liquid chromatography-electrospray ionisation-mass spectrometry (LC-ESI-MS) method has been developed and validated for the identification and determination of seven flavonoids, namely epimedin A, epimedin B, epimedin C, icariin, sagittatoside B, 2"-0-rhamnosyl icariside II, and baohuoside I in Epimedium from different sources.

  9. Tunable secondary dimension selectivity in comprehensive two-dimensional gas chromatography

    NARCIS (Netherlands)

    J. Mommers; G. Pluimakers; J. Knooren; T. Dutriez; S. van der Wal


    In this paper two tunable two-dimensional gas chromatography setups are compared and described in which the secondary dimension consists of two different capillary columns coupled in series. In the first setup the selectivity of the second dimension can be tuned by adjusting the effective column len

  10. Planar gas chromatography column on aluminum plate with multi-walled carbon nanotubes as stationary phase (United States)

    Platonov, I. A.; Platonov, V. I.; Pavelyev, V. S.


    The high selectivity of the adsorption layer for low-boiling alkanes is shown, the separation factor (α) couple iso-butane / butane is 1.9 at a column temperature of 50 °C.The paper presents sorption and selective properties of planar gas chromatography column on aluminum plate with multi-walled carbon nanotubes as the stationary phase.

  11. Construction-Paper Puzzle Masterpieces (United States)

    Vance, Shelly


    Creating an appreciation of art history in her junior-high students has always been one of the author's greatest challenges as an art teacher. In this article, the author describes how her eighth-grade students re-created a famous work of art--piece by piece, like a puzzle or a stained-glass window--out of construction paper. (Contains 1 resource.)

  12. Paper Interfaces for Learning Geometry


    Bonnard, Quentin; Verma, Himanshu; Kaplan, Frédéric; Dillenbourg, Pierre


    Paper interfaces offer tremendous possibilities for geometry education in primary schools. Existing computer interfaces designed to learn geometry do not consider the integration of conventional school tools, which form the part of the curriculum. Moreover, most of computer tools are designed specifically for individual learning, some propose group activities, but most disregard classroom-level learning, thus impeding their adoption. We present an augmented reality based tabletop system with ...

  13. Detection of landmines (Review Paper

    Directory of Open Access Journals (Sweden)

    A.K. Sinha


    Full Text Available Detection of landmines is a problem concerning both military and peacekeeping forces. This paper reviews literature on strategic minefield layouts, modern mine clearing, and mine countermeasure techniques based on mechanical methods. Discusses hydraulic and signal processing techniques, ion-trap mobility spectrometer, subsurface probing radar and few other novel methods employed for this purpose. The specialised directions that the landmine detection methods are taking are clearly pointed out.



    Simran Karamchandani*, Sourabh Choudhary


    The internetworking of physical devices, vehicles buildings and other items—embedded with electronics, software, sensors, and network connectivity that enable these objects to collect and exchange data. The IoT allows objects to be sensed and controlled remotely across existing network infrastructure, creating opportunities for more direct integration of the physical world into computer-based systems, and resulting in improved efficiency. In this paper we are discussing the problems exist in ...

  15. Photoerasing paper and thermocoloring film (United States)

    Kanakkanatt, Sebastian V.


    Thermal coloration of spiropyrans and spiroxazines at or above their melting point is well known to photochromists. The erasure of the color developed by exposure of photochromic paper by radiations of certain wavelengths in the visible region is little known. Six-nitrospirobenzopyran and 8- nitrospirobenzopyran, 8-methoxy-6-nitrospirobenzo-pyran, 6- methoxy-8-nitrospirobenzopyran, and 6,8-dinitrospirobenzopyran have been studied. The medium in which these photochromic dyes were dissolved or incorporated was limited to cellulose derivatives such as cellulose acetate, cellulose acetate- butyrate, and cellulose trinitrate. Paper coated with 6- nitrospirobenzopyran dissolved in an ethyl acetate solution of cellulose trinitrate readily colored on exposure to UV light or IR radiation and faded on exposure to light in the visible range. This unusual phenomenon, although not fully understood, is believed to be a selective light sensitizing ability of nitro groups. The applications of photoerasing paper and thermally colorable films are numerous, such as in polaroid type photography, in copy machines, and in thermally stable photochromic ophthalmic lenses.

  16. Low thermal mass liquid chromatography. (United States)

    Gu, Binghe; Cortes, Hernan; Luong, Jim; Pursch, Matthias; Eckerle, Patric; Mustacich, Robert


    A novel technique, low thermal mass liquid chromatography (LTMLC), is introduced in this study. The use of an LTM assembly that utilizes the principle of resistive wire heating and a temperature sensor to accurately deliver unprecedented heating (up to 1800 degrees C/min) or cooling (100 to approximately 200 degrees C/min) rates is reported. With the use of packed microcolumns (heat transfer from the assembly to the mobile phase was obtained. A systematic investigation was conducted to study the performance of the LTMLC technique. Both isocratic and gradient mobile phase conditions were used. For temperature control, isothermal, temperature-increasing, and temperature-decreasing gradients were applied. Three model mixtures, two of which containing neutral and acidic analytes and the other containing neutral, acidic, and basic analytes, were used to study the effect of temperature on elution time, resolution, column efficiency, and selectivity. It was found that the LTMLC experimental setup delivered reliable temperature control, as evidenced by linear van't Hoff plots for neutral and acidic compounds. The effect of temperature on the elution of basic analytes yielded nonlinear van't Hoff plots, explaining the dramatic selectivity changes observed for bases with changes in column temperature. Column efficiency generally increased with the increase in column temperature in the range of 25 to approximately 75 degrees C and decreased in the range of 75 to approximately 150 degrees C at a fixed column flow rate (3 microL/min), when extra column band broadening was taken into account. The increase in efficiency upon the increase in column temperature in the low temperature range was mainly due to the decreased mass transfer term resulting from increased analyte diffusivity. However, under even higher temperatures, the longitudinal diffusion dominated band broadening, explaining the decrease in column efficiency upon a further increase in column temperature. Resolution

  17. Comprehensive two-dimensional liquid chromatography: Ion chromatography × reversed-phase liquid chromatography for separation of low-molar-mass organic acids

    NARCIS (Netherlands)

    S.S. Brudin; R.A. Shellie; P.R. Haddad; P.J. Schoenmakers


    In the work presented here a novel approach to comprehensive two-dimensional liquid chromatography is evaluated. Ion chromatography is chosen for the first-dimension separation and reversed-phase liquid chromatography is chosen for the second-dimension separation mode. The coupling of these modes is

  18. Published papers on telepathology projects

    Directory of Open Access Journals (Sweden)

    Sadrieh Hajesmaeel-Gohari


    Full Text Available Introduction: Although many studies have been conducted in the telepathology field in recent years, a systematic review that examines studies in a comparative manner has not yet been undertaken. This paper aims to review the published papers on telepathology projects and compare them in several aspects such as telepathology method,telecommunication method, clinical outcome, etc. Method: This is a systematic review study. PubMed database was used to find the studies published in the past ten years (2004–2014. The 71 final related papers were evaluated. Data were extracted from these studies based on the following items: country, national (in country or international (between countries, frozen section or slide, body part, type of camera used, telecommunication method, telepathology method, clinical outcome, cost evaluation, satisfaction evaluation and the description of consultation providers and receivers. Data were analyzed using descriptive analysis. Results: Results showed that most of the studies were performed in developed countries on a national level, on slide and on a specific body part. In most studies, a Nikon camera was used to take images. Online methods were the most used telecommunication method in the studies, while store and forward was the most used telepathology method. Clinical outcome of many studies showed that telepathology is a reliable and accurate method for consultation. More than half of the studies considered the cost, and most of them showed that a telepathology system is cost effective. Few studies evaluated satisfaction of the participants. In most studies, the telepathology project was undertaken between pathologists. Conclusion: Although there is enough evidence to suggest that telepathology is an effective way of consultation between pathologists, there are still some areas that should be addressed and for which there is a lack of convincing evidence. For example, pathologist satisfaction, cost evaluation

  19. Combination of integrated expanded bed adsorption chromatography and countercurrent chromatography for the direct extraction and purification of pseudohypericin and hypericin from St. John's wort (Hypericum perforatum L.). (United States)

    Cai, Fanfan; Li, Yang; Zhang, Min; Zhang, Hongyang; Wang, Yuerong; Hu, Ping


    St. John's wort has attracted particular attention because of its beneficial effects as an antidepressant, antiviral, and anticancer agent. A method for the combination of integrated expanded bed adsorption chromatography and countercurrent chromatography for the simultaneous extraction and purification of pseudohypericin and hypericin from the herb is presented in this paper. Firstly, the constituents were extracted and directly adsorbed by expanded bed adsorption chromatography under optimal conditions. The stepwise elution was then performed by expanded bed adsorption chromatography that enriched the targets with higher purities and recoveries compared to other methods. Secondly, the eluent fractions from expanded bed adsorption chromatography were further separated by two-step high-speed countercurrent chromatography. A two-step high-speed countercurrent chromatography method with a biphasic solvent system composed of n-hexane/ethyl acetate/methanol/water with a volume ratio of 1:2:1:2 was performed by stepwise changing the flow rate of the mobile phase. Consequently, 5.6 mg of pseudohypericin and 2.2 mg of hypericin with purities of 95.5 and 95.0%, respectively, were successfully obtained from 40 mg of crude sample.

  20. Relativity on Rotated Graph Paper

    CERN Document Server

    Salgado, Roberto B


    We present visual calculations in special relativity using spacetime diagrams drawn on graph paper that has been rotated by 45 degrees. The rotated lines represent lightlike directions in Minkowski spacetime, and the boxes in the grid (called "light-clock diamonds") represent units of measurement modeled on the ticks of an inertial observer's lightclock. We show that many quantitative results can be read off a spacetime diagram by counting boxes, using a minimal amount of algebra. We use the Doppler Effect, in the spirit of the Bondi k-calculus, to motivate the method.

  1. White Paper on Nuclear Astrophysics


    Arcones, Almudena; Bardayan, Dan W.; Beers, Timothy C.; Berstein, Lee A.; Blackmon, Jeffrey C.; Messer, Bronson; Brown, B. Alex; Brown, Edward F; Brune, Carl R.; Champagne, Art E.; Chieffi, Alessandro; Couture, Aaron J.; Danielewicz, Pawel; Diehl, Roland; El-Eid, Mounib


    This white paper informs the nuclear astrophysics community and funding agencies about the scientific directions and priorities of the field and provides input from this community for the 2015 Nuclear Science Long Range Plan. It summarizes the outcome of the nuclear astrophysics town meeting that was held on August 21-23, 2014 in College Station at the campus of Texas A&M University in preparation of the NSAC Nuclear Science Long Range Plan. It also reflects the outcome of an earlier town mee...

  2. A New Glow on the Chromatography of M&M Candies (United States)

    Birdwhistell, Kurt R.; Spence, Thomas G.


    This lab experiment for undergraduate or high school students presents the separation and analysis of dyes in the candy shell of M&M chocolate candies. The dyes in the shells of M&Ms are separated using paper chromatography and are identified by comparison of the Rf values, color, and fluorescence properties with those of standard FD&C ([U.S. Federal] Food, Drug, and Cosmetic Act) dyes. The experiment introduces students to chromatography of mixtures, compound identification by using Rf values, and fluorescence. They learn about fluorescence and how it appears in everyday substances and can be used to help identify compounds.

  3. Cromatografia gasosa bidimensional abrangente (GC × GC Comprehensive two-dimensional gas chromatography (GC × GC

    Directory of Open Access Journals (Sweden)

    Marcio Pozzobon Pedroso


    Full Text Available This paper presents the fundamental principles, instrumentation and selected applications of comprehensive two-dimensional gas chromatography (GC × GC. In this technique, introduced in 1991, two capillary columns are coupled and proper modulating interfaces continuously collect the eluate from the first column, transferring it to the second column. The result is a geometric increment in the chromatographic resolution, ensuring separation of extremely complex mixtures in time periods shorter or comparable to those of analysis using conventional gas chromatography and with better detectabilities and sensitivities.


    Institute of Scientific and Technical Information of China (English)

    SuZhengquan; FengHuixia; 等


    The tetravalent metal salts of monoalkyl phosphates [M(O3POR)2]are a new kind of stationary phases of Chromatography-homogeneous bonded phases.This paper deals with the application of cerium bis(monomyristylphosphate)as support to reversed phase liquid chromatography.The results show that the best mobil phase is CH3CN:H2O=95:5.The good separation to the mixture containing six aromatic hydrocarbons and the determination of naphthalene in a group samples have been achieved.The regression analysis shows that detect limits,linearities and precision for six aromatic hydrocarbons are good.

  5. White Paper on Nuclear Astrophysics

    CERN Document Server

    Arcones, Almudena; Beers, Timothy; Berstein, Lee; Blackmon, Jeff; Bronson, Messer; Brown, Alex; Brown, Edward; Brune, Carl; Champagne, Art; Chieffi, Alessandro; Couture, Aaron; Danielewicz, Pawel; Diehl, Roland; El-Eid, Mounib; Escher, Jutta; Fields, Brian; Frohlich, Carla; Herwig, Falk; Hix, William Raphael; Iliadis, Christian; Lynch, William; McLaughlin, Gail; Meyer, Bradley; Mezzacappa, Anthony; Nunes, Filomena; O'Shea, Brian; Prakash, Madappa; Pritychenko, Boris; Reddy, Sanjay; Rehm, Ernst; Rogachev, Grigory; Rutledge, Robert; Schatz, Hendrik; Smith, Michael; Stairs, Ingrid; Steiner, Andrew; Strohmayer, Tod; Timmes, Frank; Townsley, Dean; Wiescher, Michael; Zegers, Remco; Zingale, Michael


    This white paper informs the nuclear astrophysics community and funding agencies about the scientific directions and priorities of the field and provides input from this community for the 2015 Nuclear Science Long Range Plan. It summarizes the outcome of the nuclear astrophysics town meeting that was held on August 21-23, 2014 in College Station at the campus of Texas A&M University in preparation of the NSAC Nuclear Science Long Range Plan. It also reflects the outcome of an earlier town meeting of the nuclear astrophysics community organized by the Joint Institute for Nuclear Astrophysics (JINA) on October 9- 10, 2012 Detroit, Michigan, with the purpose of developing a vision for nuclear astrophysics in light of the recent NRC decadal surveys in nuclear physics (NP2010) and astronomy (ASTRO2010). The white paper is furthermore informed by the town meeting of the Association of Research at University Nuclear Accelerators (ARUNA) that took place at the University of Notre Dame on June 12-13, 2014. In summ...

  6. The Blue Box White Paper

    CERN Document Server

    Tippett, Benjamin K


    This white paper is an explanation of Ben and Dave's TARDIS time machine, written for laypeople who are interested in time travel, but have no technical knowledge of Einstein's Theory of General Relativity. The first part of this paper is an introduction to the pertinent ideas from Einstein's theory of curved spacetime, followed by a review of other popular time machine spacetimes. We begin with an introduction to curvature and lightcones. We then explain the Alcubierre Warp Drive, the Morris-Thorne wormhole, and the Tipler cylinder. We then describe the Traversable Achronal Retrograde Domain in Spacetime (TARDIS), and explain some of its general properties. Our TARDIS is a bubble of spacetime curvature which travels along a closed loop in space and time. A person travelling within the bubble will feel a constant acceleration. A person outside of the TARDIS will see two bubbles: one which is evolving forwards in time, and one which is evolving backwards in time. We then discuss the physical limitations which ...

  7. High-performance liquid chromatography of biopolymers

    Energy Technology Data Exchange (ETDEWEB)

    Regnier, F.E.


    The ability to separate biological macromolecules with good resolution on liquid chromatographic columns has depended on the development of suitable packing materials. In size exclusion chromatography, molecules are separated by size on the basis of differential permeation of the packing. Ion exchange, hydrophobic interaction (or reversed-phase), and affinity chromatography are all surface-mediated separation methods, although they depend on different retention mechanisms. High-performance liquid chromatographic columns designed for biopolymers offer major advantages over conventional columns in both speed and resolving power. The exponential growth of literature on the high-performance separation of peptides and proteins in particular indicates that the techniques will become the dominant form of column liquid chromatography. 92 refs., 4 figs.

  8. Diagonal chromatography to study plant protein modifications. (United States)

    Walton, Alan; Tsiatsiani, Liana; Jacques, Silke; Stes, Elisabeth; Messens, Joris; Van Breusegem, Frank; Goormachtig, Sofie; Gevaert, Kris


    An interesting asset of diagonal chromatography, which we have introduced for contemporary proteome research, is its high versatility concerning proteomic applications. Indeed, the peptide modification or sorting step that is required between consecutive peptide separations can easily be altered and thereby allows for the enrichment of specific, though different types of peptides. Here, we focus on the application of diagonal chromatography for the study of modifications of plant proteins. In particular, we show how diagonal chromatography allows for studying proteins processed by proteases, protein ubiquitination, and the oxidation of protein-bound methionines. We discuss the actual sorting steps needed for each of these applications and the obtained results. This article is part of a Special Issue entitled: Plant Proteomics--a bridge between fundamental processes and crop production, edited by Dr. Hans-Peter Mock.

  9. Liquid chromatography detection unit, system, and method

    Energy Technology Data Exchange (ETDEWEB)

    Derenzo, Stephen E.; Moses, William W.


    An embodiment of a liquid chromatography detection unit includes a fluid channel and a radiation detector. The radiation detector is operable to image a distribution of a radiolabeled compound as the distribution travels along the fluid channel. An embodiment of a liquid chromatography system includes an injector, a separation column, and a radiation detector. The injector is operable to inject a sample that includes a radiolabeled compound into a solvent stream. The position sensitive radiation detector is operable to image a distribution of the radiolabeled compound as the distribution travels along a fluid channel. An embodiment of a method of liquid chromatography includes injecting a sample that comprises radiolabeled compounds into a solvent. The radiolabeled compounds are then separated. A position sensitive radiation detector is employed to image distributions of the radiolabeled compounds as the radiolabeled compounds travel along a fluid channel.

  10. Comparison of Membrane Chromatography and Monolith Chromatography for Lactoferrin and Bovine Serum Albumin Separation

    Directory of Open Access Journals (Sweden)

    Chalore Teepakorn


    Full Text Available These last few decades, membranes and monoliths have been increasingly used as stationary phases for chromatography. Their fast mass transfer is mainly based on convection, which leads to reduced diffusion, which is usually observed in resins. Nevertheless, poor flow distribution, which causes inefficient binding, remains a major challenge for the development of both membrane and monolith devices. Moreover, the comparison of membranes and monoliths for biomolecule separation has been very poorly investigated. In this paper, the separation of two proteins, bovine serum albumin (BSA and lactoferrin (LF, with similar sizes, but different isoelectric points, was investigated at a pH of 6.0 with a BSA-LF concentration ratio of 2/1 (2.00 mg·mL−1 BSA and 1.00 mg·mL−1 LF solution using strong cation exchange membranes and monoliths packed in the same housing, as well as commercialized devices. The feeding flow rate was operated at 12.0 bed volume (BV/min for all devices. Afterward, bound LF was eluted using a phosphate-buffered saline solution with 2.00 M NaCl. Using membranes in a CIM housing from BIA Separations (Slovenia with porous frits before and after the membrane bed, higher binding capacities, sharper breakthrough curves, as well as sharper and more symmetric elution peaks were obtained. The monolith and commercialized membrane devices showed lower LF binding capacity and broadened and non-symmetric elution peaks.

  11. Relativity on rotated graph paper (United States)

    Salgado, Roberto B.


    We demonstrate a method for constructing spacetime diagrams for special relativity on graph paper that has been rotated by 45°. The diagonal grid lines represent light-flash worldlines in Minkowski spacetime, and the boxes in the grid (called "clock diamonds") represent units of measurement corresponding to the ticks of an inertial observer's light clock. We show that many quantitative results can be read off a spacetime diagram simply by counting boxes, with very little algebra. In particular, we show that the squared interval between two events is equal to the signed area of the parallelogram on the grid (called the "causal diamond") with opposite vertices corresponding to those events. We use the Doppler effect—without explicit use of the Doppler formula—to motivate the method.

  12. Object technology: A white paper

    Energy Technology Data Exchange (ETDEWEB)

    Jordan, S.R.; Arrowood, L.F.; Cain, W.D.; Stephens, W.M.; Vickers, B.D.


    Object-Oriented Technology (OOT), although not a new paradigm, has recently been prominently featured in the trade press and even general business publications. Indeed, the promises of object technology are alluring: the ability to handle complex design and engineering information through the full manufacturing production life cycle or to manipulate multimedia information, and the ability to improve programmer productivity in creating and maintaining high quality software. Groups at a number of the DOE facilities have been exploring the use of object technology for engineering, business, and other applications. In this white paper, the technology is explored thoroughly and compared with previous means of developing software and storing databases of information. Several specific projects within the DOE Complex are described, and the state of the commercial marketplace is indicated.

  13. Chemically modified cellulose paper as a thin film microextraction phase. (United States)

    Saraji, Mohammad; Farajmand, Bahman


    In this paper, chemically modified cellulose paper was introduced as a novel extracting phase for thin film microextraction (TFME). Different reagents (Octadecyltrichlorosilane, diphenyldichlorosilane, cyclohexyl isocyanate and phenyl isocyanate) were used to modify the cellulose papers. The modified papers were evaluated as a sorbent for the extraction of some synthetic and natural estrogenic hormones (17α-ethynylestradiol, estriol and estradiol) from aqueous samples. Liquid chromatography-fluorescence detection was used for the quantification of the extracted compounds. The cellulose paper modified with phenyl isocyanate showed the best affinity to the target compounds. TEME parameters such as desorption condition, shaking rate, sample ionic strength and extraction time were investigated and optimized. Limit of detections were between 0.05 and 0.23μgL(-1) and relative standard deviations were less than 11.1% under the optimized condition. The calibration curves were obtained in the range of 0.2-100μgL(-1) with a good linearity (r(2)>0.9935). Wastewater, human urine, pool and river water samples were studied as real samples for the evaluation of the method. Relative recoveries were found to be between 75% and 101%.

  14. Self-interaction chromatography as a tool for optimizing conditions for membrane protein crystallization. (United States)

    Gabrielsen, Mads; Nagy, Lisa A; DeLucas, Lawrence J; Cogdell, Richard J


    The second virial coefficient, or B value, is a measurement of how well a protein interacts with itself in solution. These interactions can lead to protein crystallization or precipitation, depending on their strength, with a narrow range of B values (the 'crystallization slot') being known to promote crystallization. A convenient method of determining the B value is by self-interaction chromatography. This paper describes how the light-harvesting complex 1-reaction centre core complex from Allochromatium vinosum yielded single straight-edged crystals after iterative cycles of self-interaction chromatography and crystallization. This process allowed the rapid screening of small molecules and detergents as crystallization additives. Here, a description is given of how self-interaction chromatography has been utilized to improve the crystallization conditions of a membrane protein.

  15. Demonstrating Chemical and Analytical Concepts in the Undergraduate Laboratory Using Capillary Electrophoresis and Micellar Electrokinetic Chromatography (United States)

    Palmer, Christopher P.


    This paper describes instrumental analysis laboratory exercises that utilize capillary electrophoresis and micellar electrokinetic chromatography to demonstrate several analytical and chemical principles. Alkyl parabens (4-hydroxy alkyl benzoates), which are common ingredients in cosmetic formulations, are separated by capillary electrophoresis. The electrophoretic mobilities of the parabens can be explained on the basis of their relative size. 3-Hydroxy ethylbenzoate is also separated to demonstrate the effect of substituent position on the acid dissociation constant and the effect this has on electrophoretic mobility. Homologous series of alkyl benzoates and alkyl phthalates (common plasticizers) are separated by micellar electrokinetic chromatography at four surfactant concentrations. This exercise demonstrates the separation mechanism of micellar electrokinetic chromatography, the concept of chromatographic phase ratio, and the concepts of micelle formation. A photodiode array detector is used in both exercises to demonstrate the advantages and limitations of the detector and to demonstrate the effect of pH and substituent position on the spectra of the analytes.

  16. Introduction to the Paper Symposium (United States)

    Carpenter, D. K.


    Most students of physical chemistry, as well as their teachers, regard equilibrium chemical thermodynamics as an impressive, useful, and stable subject that was "finished" long ago. As part of their education, students in physical chemistry have been taught the importance and the usefulness of the Gibbs function (formerly called the Gibbs free energy function). The antiquity of the subject and the presumed mastery of its basics by physical chemistry teachers are taken for granted as given parts of the educational and scientific scene in chemical education. It comes as a surprise to occasionally discover that even those who teach this venerable subject sometimes disagree, not merely in matters of style or organization of the subject, or in matters of mathematical elegance, but in matters of real substance. The following four papers are examples of this. My role here is simply to introduce this set of papers and to provide some orientation regarding their contents. The authors have been in private communication with each other for a period of over four years about the use and the proper definition of the Gibbs function. The lengthy period of correspondence has not resulted in any significant agreement. The Editor of this Journal was unable to settle the resulting controversy by normal review procedures. In an attempt to break the deadlock he asked me, as an impartial outsider to the situation, for assistance in deciding an appropriate literary form in which the authors could present their own points of view as well as comments on the views of the other authors. The original hope was that agreement could eventually be reached on disputed points by the give and take of the interchange of further correspondence, and that the outcome would be published in the form of a "paper symposium" on the subject, with me as the "chairman" of the symposium. It must be said at the outset that the prolonged correspondence has not produced much agreement among the authors. This is

  17. 29 CFR 570.63 - Occupations involved in the operation of paper-products machines, scrap paper balers, and paper... (United States)


    ... machines, scrap paper balers, and paper box compactors (Order 12). 570.63 Section 570.63 Labor Regulations... involved in the operation of paper-products machines, scrap paper balers, and paper box compactors (Order..., scrap paper baler, paper box compactor, or vertical slotter. (ii) Platen die-cutting press,...

  18. Replacing paper with digital recording. (United States)

    Amin, Kawa


    Addressing the needs to achieve the highest standards at multidisciplinary team meetings at the Stroke Unit of Broomfield Hospital, an electronic version is applied instead of the traditional paper model. This is to ensure that patients within the unit are receiving appropriate care and their progress is monitored throughout their entire journey. This also enables the stroke team to retrieve old information anywhere in the hospital, electronically, from previous documentations to compare progress of rehabilitation. The electronic model also helps when assessing readmission or those who attend the stroke clinics to clarify new onset changes from residual weakness. The tool kit estimates Barthel Index score for activities of daily living and Rivermead Mobility Index for physical capacity assessment weekly as the team attending the meetings. The goals from all disciplines, physiotherapists, occupational therapists, speech and language therapists, and nurses are clearly documented along with patient cognition, emotion, and perception. This initiative commenced in late April 2013 and the first clinical outcome assessments performed at the beginning of September 2013, enabling the stroke team to assess rehabilitation activities and achievements. Front-line staff expressed satisfaction with the initiative model, which successfully managed to monitor and analyze the rehabilitation activities within the stroke unit.

  19. Challenge of Biotechnology (Review Paper

    Directory of Open Access Journals (Sweden)

    Malcolm R. Dando


    Full Text Available The unravelling of the human genetic code whose first draft was announced in June 2000 has rightly blood been hailed as a momentous achievement, opening thc book of life, certain to be the dominant technology of the 21st century, which will inform all about medicine and biology. and lead us to a total understanding of life. Simultaneously, concerns have been expressed about thc implications of this work. In the past, major new technologies have been used intensively for hostile purposes. What is thc challenge that biotechnology poses in this regard'? This review paper looks at the enormous changes in civil society that thc genomics revolution could bring. Against this background, thc growing concerns about its potential misuses have been reviewed. Thc strengths and weaknesses or the Biological and Toxin Weapons Convention (BTWC are then touched upon. The BTWC presently lacks an adequate verification mechanism. Although biotechnology has been used by human beings since prehistoric times (eg. making of bread. cheese. wines its scientific understanding came only in the latter part of the 19th century. Thc decisive turning point in the field came in the 1970s with the advent of genetic engineering. In the military context classical agents like anthrax and toxin remain the threat today. Although thc current level or sophistication for many biological agents is low, there is enormous potential for making more sophisticated weapons. It might be possible to specifically target the genetic makeup of different ethnic groups. The limited varieties of staple crops and the limited strains of modern animals make agriculture particularly open to attack. Another serious possibility is the impact of genomics in neuroscience. With a better understanding of cellular receptor systems and bioregulators, it is not inconceivable that new means would be evolved for disturbing the functions of the nervous system. Thc genomics revolution can be used for peaceful purposes

  20. Community energy management : foundation paper

    Energy Technology Data Exchange (ETDEWEB)



    This paper examined the potential for community energy management (CEM) to contribute to the reduction of greenhouse gas emissions in Canada. CEM is the integration of energy considerations into municipal planning and management processes so that the benefits of such planning exceed the impacts of individual initiatives. The goals of CEM may be to reduce public sector expenditures, job creation and improving the quality of life. The main initiative is to create more livable communities with affordable housing in attractive environments that enhance accessibility to services and employment, preserve green space, reduce pollution and noise and create a safer urban landscape. CEM typically encompasses land use planning, transportation management, influencing design, and fostering efficient and environmentally benign energy supply and delivery systems. Two particular aspects of CEM were examined in detail. The first was the relationship between land use and energy use and the second was the potential for district energy systems in Canadian communities. District heating has proven to make a significant difference in the overall energy intensity of urban settlements. It is a long accepted technology in Europe where entire district energy systems replace the furnaces of individual buildings. The advantage of district energy systems is the wide variety of fuels and energy sources that can be used to fire the boilers. They can also achiever higher levels of efficiency. District energy can be designed to provide for domestic hot water heating needs for both residential and business purposes, and as such, waste heat from industrial activities or power production is sufficient. District energy systems can also burn municipal solid waste, methane from landfill sites and sewage gas. There are currently 160 district energy systems in operation in Canada. 64 refs., 8 tabs., 2 figs.

  1. High Performance Liquid Chromatography Experiments to Undergraduate Laboratories (United States)

    Kissinger, Peter T.; And Others


    Reviews the principles of liquid chromatography with electrochemical detection (LCEC), an analytical technique that incorporates the advantages of both liquids chromatography and electrochemistry. Also suggests laboratory experiments using this technique. (MLH)

  2. The History of Ion Chromatography: The Engineering Perspective (United States)

    Evans, Barton


    The development of ion chromatography from an engineering perspective is presented. As ion chromatography became more widely accepted, researchers developed dozens of standard applications that enabled the creation of many low-end instruments.

  3. Purification of chimeric heavy chain monoclonal antibody EG2-hFc using hydrophobic interaction membrane chromatography: an alternative to protein-A affinity chromatography. (United States)

    Sadavarte, Rahul; Spearman, Maureen; Okun, Natalie; Butler, Michael; Ghosh, Raja


    Heavy chain monoclonal antibodies are being considered as alternative to whole-IgG monoclonal antibodies for certain niche applications. Protein-A chromatography which is widely used for purifying IgG monoclonal antibodies is also used for purifying heavy chain monoclonal antibodies as these molecules possess fully functional Fc regions. However, the acidic conditions used to elute bound antibody may sometimes also leach protein-A, which is immunotoxic. Low pH conditions also tend to make the mAb molecules unstable and prone to aggregation. Moreover, protein-A affinity chromatography does not remove aggregates already present in the feed. Hydrophobic interaction membrane chromatography (or HIMC) has already been studied as an alternative to protein-A chromatography for purifying whole-IgG monoclonal antibodies. This paper describes the use of HIMC for capturing a humanized chimeric heavy chain monoclonal antibody (EG2-hFC). Binding and eluting conditions were suitably optimized using pure EG2-hFC. Based on this, an HIMC method was developed for capture of EG2-hFC directly from cell culture supernatant. The EG2-hFc purity obtained in this single-step process was high. The glycan profiles of protein-A and HIMC purified monoclonal antibody samples were similar, clearly demonstrating that both techniques captured similarly glycosylated population of EG2-hFc. Moreover, this technique was able to resolve aggregates from monomeric form of the EG2-hFc.

  4. Application of a chromatography model with linear gradient elution experimental data to the rapid scale-up in ion-exchange process chromatography of proteins. (United States)

    Ishihara, Takashi; Kadoya, Toshihiko; Yamamoto, Shuichi


    We applied the model described in our previous paper to the rapid scale-up in the ion exchange chromatography of proteins, in which linear flow velocity, column length and gradient slope were changed. We carried out linear gradient elution experiments, and obtained data for the peak salt concentration and peak width. From these data, the plate height (HETP) was calculated as a function of the mobile phase velocity and iso-resolution curve (the separation time and elution volume relationship for the same resolution) was calculated. The scale-up chromatography conditions were determined by the iso-resolution curve. The scale-up of the linear gradient elution from 5 to 100mL and 2.5L column sizes was performed both by the separation of beta-lactoglobulin A and beta-lactoglobulin B with anion-exchange chromatography and by the purification of a recombinant protein with cation-exchange chromatography. Resolution, recovery and purity were examined in order to verify the proposed method.

  5. Christhin: Quantitative Analysis of Thin Layer Chromatography

    CERN Document Server

    Barchiesi, Maximiliano; Renaudo, Carlos; Rossi, Pablo; Pramparo, María de Carmen; Nepote, Valeria; Grosso, Nelson Ruben; Gayol, María Fernanda


    Manual for Christhin 0.1.36 Christhin (Chromatography Riser Thin) is software developed for the quantitative analysis of data obtained from thin-layer chromatographic techniques (TLC). Once installed on your computer, the program is very easy to use, and provides data quickly and accurately. This manual describes the program, and reading should be enough to use it properly.

  6. Phosphopeptide enrichment by immobilized metal affinity chromatography

    DEFF Research Database (Denmark)

    Thingholm, Tine E.; Larsen, Martin R.


    Immobilized metal affinity chromatography (IMAC) has been the method of choice for phosphopeptide enrichment prior to mass spectrometric analysis for many years and it is still used extensively in many laboratories. Using the affinity of negatively charged phosphate groups towards positively...

  7. Three dimensional liquid chromatography coupling ion exchange chromatography/hydrophobic interaction chromatography/reverse phase chromatography for effective protein separation in top-down proteomics. (United States)

    Valeja, Santosh G; Xiu, Lichen; Gregorich, Zachery R; Guner, Huseyin; Jin, Song; Ge, Ying


    To address the complexity of the proteome in mass spectrometry (MS)-based top-down proteomics, multidimensional liquid chromatography (MDLC) strategies that can effectively separate proteins with high resolution and automation are highly desirable. Although various MDLC methods that can effectively separate peptides from protein digests exist, very few MDLC strategies, primarily consisting of 2DLC, are available for intact protein separation, which is insufficient to address the complexity of the proteome. We recently demonstrated that hydrophobic interaction chromatography (HIC) utilizing a MS-compatible salt can provide high resolution separation of intact proteins for top-down proteomics. Herein, we have developed a novel 3DLC strategy by coupling HIC with ion exchange chromatography (IEC) and reverse phase chromatography (RPC) for intact protein separation. We demonstrated that a 3D (IEC-HIC-RPC) approach greatly outperformed the conventional 2D IEC-RPC approach. For the same IEC fraction (out of 35 fractions) from a crude HEK 293 cell lysate, a total of 640 proteins were identified in the 3D approach (corresponding to 201 nonredundant proteins) as compared to 47 in the 2D approach, whereas simply prolonging the gradients in RPC in the 2D approach only led to minimal improvement in protein separation and identifications. Therefore, this novel 3DLC method has great potential for effective separation of intact proteins to achieve deep proteome coverage in top-down proteomics.

  8. Instrument platforms for nano liquid chromatography. (United States)

    Šesták, Jozef; Moravcová, Dana; Kahle, Vladislav


    The history of liquid chromatography started more than a century ago and miniaturization and automation are two leading trends in this field. Nanocolumn liquid chromatography (nano LC) and largely synonymous capillary liquid chromatography (capillary LC) are the most recent results of this process where miniaturization of column dimensions and sorbent particle size play crucial role. Very interesting results achieved in the research of extremely miniaturized LC columns at the end of the last century lacked distinctive raison d'être and only advances in mass spectrometry brought a real breakthrough. Configuration of nano LC-electrospray ionization mass spectrometry (LC-ESI-MS) has become a basic tool in bioanalytical chemistry, especially in proteomics. This review discusses and summarizes past and current trends in the realization of nano liquid chromatography (nano LC) platforms. Special attention is given to the mobile phase delivery under nanoflow rates (isocratic, gradient) and sample injection to the nanocolumn. Available detection techniques applied in nano LC separations are also briefly discussed. We followed up the key themes from the original scientific reports over gradual improvements up to the contemporary commercial solutions.

  9. Structures of multidomain proteins adsorbed on hydrophobic interaction chromatography surfaces. (United States)

    Gospodarek, Adrian M; Sun, Weitong; O'Connell, John P; Fernandez, Erik J


    In hydrophobic interaction chromatography (HIC), interactions between buried hydrophobic residues and HIC surfaces can cause conformational changes that interfere with separations and cause yield losses. This paper extends our previous investigations of protein unfolding in HIC chromatography by identifying protein structures on HIC surfaces under denaturing conditions and relating them to solution behavior. The thermal unfolding of three model multidomain proteins on three HIC surfaces of differing hydrophobicities was investigated with hydrogen exchange mass spectrometry (HXMS). The data were analyzed to obtain unfolding rates and Gibbs free energies for unfolding of adsorbed proteins. The melting temperatures of the proteins were lowered, but by different amounts, on the different surfaces. In addition, the structures of the proteins on the chromatographic surfaces were similar to the partially unfolded structures produced in the absence of a surface by temperature as well as by chemical denaturants. Finally, it was found that patterns of residue exposure to solvent on different surfaces at different temperatures can be largely superimposed. These findings suggest that protein unfolding on various HIC surfaces might be quantitatively related to protein unfolding in solution and that details of surface unfolding behavior might be generalized.

  10. Analysis of Some Biogenic Amines by Micellar Liquid Chromatography

    Directory of Open Access Journals (Sweden)

    Irena Malinowska


    Full Text Available Micellar liquid chromatography (MLC with the use of high performance liquid chromatography (HPLC was used to determine some physicochemical parameters of six biogenic amines: adrenaline, dopamine, octopamine, histamine, 2-phenylethylamine, and tyramine. In this paper, an influence of surfactant’s concentration and pH of the micellar mobile phase on the retention of the tested substances was examined. To determine the influence of surfactant’s concentration on the retention of the tested amines, buffered solutions (at pH 7.4 of ionic surfactant—sodium dodecyl sulfate SDS (at different concentrations with acetonitrile as an organic modifier (0.8/0.2 v/v were used as the micellar mobile phases. To determine the influence of pH of the micellar mobile phase on the retention, mobile phases contained buffered solutions (at different pH values of sodium dodecyl sulfate SDS (at 0.1 M with acetonitrile (0.8/0.2 v/v. The inverse of value of retention factor (1/ versus concentration of micelles ( relationships were examined. Other physicochemical parameters of solutes such as an association constant analyte—micelle (ma—and partition coefficient of analyte between stationary phase and water (hydrophobicity descriptor (swΦ were determined by the use of Foley’s equation.

  11. Microfluidic liquid chromatography system for proteomic applications and biomarker screening. (United States)

    Lazar, Iulia M; Trisiripisal, Phichet; Sarvaiya, Hetal A


    A microfluidic liquid chromatography (LC) system for proteomic investigations that integrates all the necessary components for stand-alone operation, i.e., pump, valve, separation column, and electrospray interface, is described in this paper. The overall size of the LC device is small enough to enable the integration of two fully functional separation systems on a 3 in. x 1 in. glass microchip. A multichannel architecture that uses electroosmotic pumping principles provides the necessary functionality for eluent propulsion and sample valving. The flow rates generated within these chips are fully consistent with the requirements of nano-LC platforms that are routinely used in proteomic applications. The microfluidic device was evaluated for the analysis of a protein digest obtained from the MCF7 breast cancer cell line. The cytosolic protein extract was processed according to a shotgun protocol, and after tryptic digestion and prefractionation using strong cation exchange chromatography (SCX), selected sample subfractions were analyzed with conventional and microfluidic LC platforms. Using similar experimental conditions, the performance of the microchip LC was comparable to that obtained with benchtop instrumentation, providing an overlap of 75% in proteins that were identified by more than two unique peptides. The microfluidic LC analysis of a protein-rich SCX fraction enabled the confident identification of 77 proteins by using conventional data filtering parameters, of 39 proteins with p screening applications.

  12. Performance of the same column in supercritical fluid chromatography and in liquid chromatography. (United States)

    Lambert, Nándor; Felinger, Attila


    We have studied the chromatographic behavior of the homologous series of alkylbenzenes (ranging from octylbenzene to octadecylbenzene) on the same C18 reversed-phase column in supercritical fluid chromatography (SFC) and reversed phase liquid chromatography (RPLC) at various experimental conditions, such as different eluent compositions, flow-rates, and mobile phase densities. The first and the second moments of the peaks were used to estimate the overall mass-transfer processes in both chromatographic modes using the stochastic model of chromatography. The results confirm that in SFC - as the density of the mobile phase is influenced by the flow-rate - there is a broader variation of mass-transfer properties than in liquid chromatography. As expected, the optimum mobile phase velocity is higher in SFC, but there is no real difference in the minimum value of plate height, i.e. in the optimum efficiency.

  13. CALL FOR PAPERS: Quantum control (United States)

    Mancini, Stefano; Wiseman, Howard M.; Man'ko, Vladimir I.


    Over the last few decades, the achievements of highly precise technologies for manipulating systems at quantum scales have paved the way for the development of quantum control. Moreover, the proliferation of results in quantum information suggest that control theory might profitably be re-examined from this perspective. Journal of Optics B: Quantum and Semiclassical Optics will publish a topical issue devoted to quantum control. The Guest Editors invite contributions from researchers working in any area related to quantum control. Topics to be covered include: • Quantum Hamiltonian dynamics and programming control • Quantum decoherence control • Open loop control • Closed loop (feedback) control • Quantum measurement theory • Quantum noise and filtering • Estimation and decision theory • Quantum error correction • Group representation in quantum control • Coherent control in quantum optics and lasers • Coherent control in cavity QED and atom optics • Coherent control in molecular dynamics The topical issue is scheduled for publication in November 2005 and the DEADLINE for submission of contributions is 28 February 2005. All contributions will be peer-reviewed in accordance with the normal refereeing procedures and standards of Journal of Optics B: Quantum and Semiclassical Optics. Submissions should preferably be in either standard LaTeX form or Microsoft Word. Advice on publishing your work in the journal may be found at Enquiries regarding this topical issue may be addressed to the Publisher, Dr Claire Bedrock ( There are no page charges for publication. The corresponding author of each paper published will receive a complimentary copy of the topical issue. Contributions to the topical issue should preferably be submitted electronically at or by e-mail to Authors unable to submit online or by e-mail may send hard copy contributions

  14. Chromatography purification of canine adenoviral vectors. (United States)

    Segura, María Mercedes; Puig, Meritxell; Monfar, Mercè; Chillón, Miguel


    Canine adenovirus vectors (CAV2) are currently being evaluated for gene therapy, oncolytic virotherapy, and as vectors for recombinant vaccines. Despite the need for increasing volumes of purified CAV2 preparations for preclinical and clinical testing, their purification still relies on the use of conventional, scale-limited CsCl ultracentrifugation techniques. A complete downstream processing strategy for CAV2 vectors based on membrane filtration and chromatography is reported here. Microfiltration and ultra/diafiltration are selected for clarification and concentration of crude viral stocks containing both intracellular and extracellular CAV2 particles. A DNase digestion step is introduced between ultrafiltration and diafiltration operations. At these early stages, concentration of vector stocks with good recovery of viral particles (above 80%) and removal of a substantial amount of protein and nucleic acid contaminants is achieved. The ability of various chromatography techniques to isolate CAV2 particles was evaluated. Hydrophobic interaction chromatography using a Fractogel propyl tentacle resin was selected as a first chromatography step, because it allows removal of the bulk of contaminating proteins with high CAV2 yields (88%). An anion-exchange chromatography step using monolithic supports is further introduced to remove the remaining contaminants with good recovery of CAV2 particles (58-69%). The main CAV2 viral structural components are visualized in purified preparations by electrophoresis analyses. Purified vector stocks contained intact icosahedral viral particles, low contamination with empty viral capsids (10%), and an acceptable total-to-infectious particle ratio (below 30). The downstream processing strategy that was developed allows preparation of large volumes of high-quality CAV2 stocks.

  15. High Performance Liquid Chromatography/Video Fluorometry. Part I. Instrumentation. (United States)


    High Performance Liquid Chromatography /Video...PERIOD COVERED High Performance Liquid Chromatography /Video .. / Fluorometry. Part I. Instrumentation. . Interim/ echnicaliepart,. 6. PERFORMING ORG...34Entered SECURITY CLASSIFICATION OF THIS OlAGE (When Data Entered) II1| III I I I I E I II ... .. High Performance Liquid Chromatography

  16. Separation of proteins by simulated moving bed chromatography

    NARCIS (Netherlands)

    Houwing, J.


    This thesis describes the use of simulated moving bed (SMB) chromatography for separation of proteins. The underlying aim is the increase of the efficiency of process chromatography in terms of a reduction of the sorbent and buffer consumption in comparison to fixed bed chromatography. Both size exc

  17. Differentiation of coloured inks of inkjet printer cartridges by thin layer chromatography and high performance liquid chromatography. (United States)

    Poon, N L; Ho, S S H; Li, C K


    Document examiners are frequently asked to determine whether or not a colour printout has originated from a particular inkjet printer. The printer can rarely be identified unless some unique defects or irregularities of the printer are present on the printout. However, it is possible to decipher the make and/or model of the printer by comparing the ink-profile of the questioned printout with that of a seized inkjet printer cartridge or from one in a database. This paper presents an overview of a systematic approach to characterising and discriminating the inks of different inkjet printer cartridges using thin layer chromatography (TLC) and high pressure liquid chromatography (HPLC) with multi-wavelength ultra-violet/visible (UV/Vis) detection. Ink samples from 23 different inkjet printer cartridges (including originals and substitutes) of different brands and colour printouts, printed by known printers were examined with newly developed chromatographic methods. Subsequently, a database of the ink-profiles was generated. The methods provide a useful tool for discriminating coloured inks in inkjet printer cartridges of different brands.

  18. Micellar electrokinetic chromatography (MEKC) separation of furanonaphthoquinones from Tabebuia impetiginosa. (United States)

    Koyama, J; Morita, I; Kino, A; Tagahara, K


    The separation of nine furanonaphthoquinones by micellar electrokinetic chromatography (MEKC) is described. The running electrolytes used in this method were 0.03 M sodium dodecyl sulphate (SDS) in 0.09 M borate buffer (pH 9) containing 10% methanol, with an applied voltage of 20 kV. Application of this technique in the determination of the main furanonaphthoquinones, 5-hydroxy-2-(1-hydroxyethyl)naphtho[2,3-b]furan-4,9-dione, 8-hydroxy-2-(1-hydroxyethyl)naphtho[2,3-b]furan-4,9-dione, and 2-(1-hydroxyethyl)naphtho[2,3-b]furan-4,9-dione, of Tabebuia impetiginosa is demonstrated in this paper.

  19. Zero Volt Paper Spray Ionization and Its Mechanism. (United States)

    Wleklinski, Michael; Li, Yafeng; Bag, Soumabha; Sarkar, Depanjan; Narayanan, Rahul; Pradeep, T; Cooks, R Graham


    The analytical performance and a suggested mechanism for zero volt paper spray using chromatography paper are presented. A spray is generated by the action of the pneumatic force of the mass spectrometer (MS) vacuum at the inlet. Positive and negative ion signals are observed, and comparisons are made with standard kV paper spray (PS) ionization and nanoelectrospray ionization (nESI). While the range of analytes to which zero volt PS is applicable is very similar to kV PS and nESI, differences in the mass spectra of mixtures are interpreted in terms of the more significant effects of analyte surface activity in the gentler zero volt experiment than in the other methods due to the significantly lower charge. The signal intensity of zero volt PS is also lower than in the other methods. A Monte Carlo simulation based on statistical fluctuation of positive and negative ions in solution has been implemented to explain the production of ions from initially uncharged droplets. Uncharged droplets first break up due to aerodynamics forces until they are in the 2-4 μm size range and then undergo Coulombic fission. A model involving statistical charge fluctuations in both phases predicts detection limits similar to those observed experimentally and explains the effects of binary mixture components on relative ionization efficiencies. The proposed mechanism may also play a role in ionization by other voltage-free methods.

  20. [Development of metal ions analysis by ion chromatography]. (United States)

    Yu, Hong; Wang, Yuxin


    Analysis of metal ions by ion chromatography, including cation-exchange ion chromatography, anion-exchange ion chromatography and chelation ion chromatography, is reviewed. The cation-exchange ion chromatography is a main method for the determination of metal ions. Stationary phases in cation-exchange ion chromatography are strong acid cation exchanger (sulfonic) and weak acid cation exchanger (carboxylic). Alkali metal ions, alkaline earth metal ions, transition metal ions, rare earth metal ions, ammonium ions and amines can be analyzed by cation-exchange ion chromatography with a suitable detector. The anion-exchange ion chromatography is suitable for the separation and analysis of alkaline earth metal ions, transition metal ions and rare earth metal ions. The selectivity for analysis of metal ions with anion-exchange ion chromatography is good. Simultaneous determination of metal ions and inorganic anions can be achieved using anion-exchange ion chromatography. Chelation ion chromatography is suitable for the determination of trace metal ions in complex matrices. A total of 125 references are cited.

  1. Paper-based chromatographic chemiluminescence chip for the detection of dichlorvos in vegetables. (United States)

    Liu, Wei; Kou, Juan; Xing, Huizhong; Li, Baoxin


    Paper chromatography was a big breakthrough in the early of 20th century but it is rarely used due to the long separation time and the diffusion on the sample spots. In this work, for the first time, a paper-based chemiluminescence (CL) analytical device combined with paper chromatography was developed for the determination of dichlorvos (DDV) in vegetables without complicated sample pretreatment. The paper chromatography separation procedure can be accomplished in 12 min on a paper support (0.8 × 7.0 cm(2)) by using 5 µL sample spotted on it. After sample developing, the detection area (0.8 × 1.0 cm(2)) was cut and inserted between two layers of water-impermeable single-sided adhesive tapes. The paper-based chip was made by attaching the middle layer of paper onto the bottom layer. Then it was covered by another tape layer, which was patterned by the cutting method to form a square hole (0.8 × 1.0 cm(2)) in it. 10 μL mixed solution of luminol and H2O2 was dropped on the detection area to produce CL. A linear relationship was obtained between the CL intensity and the concentrations of DDV in the range between 10.0 ng mL(-1) and 1.0 μg mL(-1)and the detection limit was 3.6 ng mL(-1). Water-soluble metal ions and vitamins can be developed at different spatial locations relative to DDV, eliminating interference with DDV during detection. The paper-based chromatographic chip can be successfully used for the determination of DDV without complicated sample preparation in vegetables. This study should, therefore, be suitable for rapid and sensitive detection of trace levels of organophosphate pesticides in environmental and food samples.

  2. Non-planar microfabricated gas chromatography column (United States)

    Lewis, Patrick R.; Wheeler, David R.


    A non-planar microfabricated gas chromatography column comprises a planar substrate having a plurality of through holes, a top lid and a bottom lid bonded to opposite surfaces of the planar substrate, and inlet and outlet ports for injection of a sample gas and elution of separated analytes. A plurality of such planar substrates can be aligned and stacked to provide a longer column length having a small footprint. Furthermore, two or more separate channels can enable multi-channel or multi-dimensional gas chromatography. The through holes preferably have a circular cross section and can be coated with a stationary phase material or packed with a porous packing material. Importantly, uniform stationary phase coatings can be obtained and band broadening can be minimized with the circular channels. A heating or cooling element can be disposed on at least one of the lids to enable temperature programming of the column.

  3. Retention models for programmed gas chromatography. (United States)

    Castello, G; Moretti, P; Vezzani, S


    The models proposed by many authors for the prediction of retention times and temperatures, peak widths, retention indices and separation numbers in programmed temperature and pressure gas chromatography by starting from preliminary measurements of the retention in isothermal and isobaric conditions are reviewed. Several articles showing the correlation between retention data and thermodynamic parameters and the determination of the optimum programming rate are reported. The columns of different polarity used for the experimental measurement and the main equations, mathematical models and calculation procedures are listed. An empirical approach was used in the early models, followed by the application of thermodynamic considerations, iterative calculation procedures and statistical methods, based on increased computing power now available. Multiple column arrangements, simultaneous temperature and pressure programming, applications of two-dimensional and fast chromatography are summarised.

  4. Protein purification using PDZ affinity chromatography. (United States)

    Walkup, Ward G; Kennedy, Mary B


    PDZ domains function in nature as protein-binding domains within scaffold and membrane-associated proteins. They comprise approximately 90 residues and undergo specific, high-affinity interactions with complementary C-terminal peptide sequences, other PDZ domains, and/or phospholipids. We have previously shown that the specific, strong interactions of PDZ domains with their ligands make them well suited for use in affinity chromatography. This unit provides protocols for the PDZ affinity chromatography procedure that are applicable for the purification of proteins that contain PDZ domains or PDZ domain-binding ligands, either naturally or introduced by genetic engineering. We detail the preparation of affinity resins composed of PDZ domains or PDZ domain peptide ligands coupled to solid supports. These resins can be used to purify proteins containing endogenous or genetically introduced PDZ domains or ligands, eluting the proteins with free PDZ domain peptide ligands.

  5. Basic prinicipal of high performance liquid chromatography


    Ivanova, Violeta


    High-performance liquid chromatography (HPLC) is an analytical technique based on the separation of molecules due to differences in their structure and/or composition. Separation is performed between two phases, mobile and stationary. The molecules in the sample have different affinities and interactions with the stationary support, leading to separation of molecules. Compounds which are longer retained at the stationary phase will elute later, compared to those which are distributed into the...

  6. Two-dimensional thin-layer chromatography in the analysis of secondary plant metabolites. (United States)

    Cieśla, Lukasz; Waksmundzka-Hajnos, Monika


    Drugs, derived from medicinal plants, have been enjoying a renaissance in the last years. It is due to a great pharmacological potential of herbal drugs, as many natural compounds have been found to exhibit biological activity of wide spectrum. The introduction of whole plants, plant extracts, or isolated natural compounds has led to the need to create the analytical methods suitable for their analysis. The identification of isolated substances is relatively an easy task, but the analysis of plant extracts causes a lot of problems, as they are usually very complex mixtures. Chromatographic methods are one of the most popular techniques applied in the analysis of natural mixtures. Unfortunately the separation power of traditional, one-dimensional techniques, is usually inadequate for separation of more complex samples. In such a case the use of multidimensional chromatography is advised. Planar chromatography gives the possibility of performing two-dimensional separations with the use of one adsorbent with two different eluents or by using bilayer plates or graft thin-layer chromatography (TLC) technique; combinations of different multidimensional techniques are also possible. In this paper, multidimensional planar chromatographic methods, commonly applied in the analysis of natural compounds, were reviewed. A detailed information is given on the methodology of performing two-dimensional separations on one adsorbent, on bilayer plates, with the use of graft TLC and hyphenated methods. General aspects of multidimensionality in liquid chromatography are also described. Finally a reader will find a description of variable two-dimensional methods applied in the analysis of compounds, most commonly encountered in plant extracts. This paper is aimed to draw attention to the potential of two-dimensional planar chromatography in the field of phytochemistry. It may be useful for those who are interested in achieving successful separations of multicomponent mixtures by means

  7. How to write English scientific paper easily

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Hyeong Sun


    This book covers definition of paper, how to write paper, as well as proofreading of paper and process of publication. It explains necessity and kinds of paper, organizations and form of paper, evaluation of paper, titles, abstracts, introductions, method of study, results, considerations, conclusions, acknowledgement and epilogue, reference, writers, pictures and tables, tense and analysis of sentences, submission of paper and ethics of publication, plagiarism, confirmation of items before writing paper, matters to be attended to drafting, and criteria and assessment of the examination of paper.

  8. On the Principle and Application of Gas Chromatography%关于气相色谱仪原理组成及使用的思考

    Institute of Scientific and Technical Information of China (English)

    厉昌海; 林隆海


    本文着重对气相色谱仪的工作原理进行分析,介绍了气相色谱分析仪的组成结构,在此基础上针对气相色谱分析仪使用过程展开论述,说明了如何才能更好的使用气相色谱分析仪%This paper mainly analyzes the working principle of gas chromatography, introduces the composition structure of gas chromatography and gas chromatography analyzer.

  9. Quantitative Analysis and Fingerprint Profiles for Quality Control of Fructus Schisandrae by Gas Chromatography: Mass Spectrometry


    Yong-Gang Xia; Bing-You Yang; Jun Liang; Qi Yang; Di Wang; Hai-Xue Kuang


    This paper describes a simple, rapid, and effective quality assessment method for Fructus Schisandrae by gas chromatography-mass spectrum (GC-MS). The method was established by using specific lignan fingerprint profiles and quantitation of characteristic compounds in this herbal medicine. The GC-MS fingerprints of 15 batches of Schisandra samples from different regions of China showed similar lignan profiles. Five peaks were selected as characteristic peaks, and all of these were identified b...

  10. Uncertainty of nitrate and sulphate measured by ion chromatography in wastewater samples



    This paper presents an evaluation of measurement uncertainty regarding the results of anion (nitrate and sulphate) concentrations in wastewater. Anions were determined by ion chromatography (EN ISO 10304-2, 1996). The major sources of uncertainty regarding the measurement results were identified as contributions to linear least-square or weighted regression lines, precision, trueness, storage conditions, and sampling. Determination of anions in wastewater is very important for the purificatio...

  11. Novel additives for the separation of organic acids by ion-pair chromatography

    Institute of Scientific and Technical Information of China (English)


    This paper proposes the use of novel surfactant additives for the separation of organic acids by ion-pair chromatography and studies the influences of surfactants on the chromatographic separation behaviors.Researches have been carried out on both silica gel matrix and polymer supporters in order to compare the two ordinary kinds of stationary phases,and the phenomenon is similar. Separation is based on differences in the stabilities of analyte-additive complexes in solution.Retention times of analytes c...

  12. Resolution of the stereoisomers of baclofen by high performance liquid chromatography

    Energy Technology Data Exchange (ETDEWEB)

    Weatherby, R.P.; Allan, R.D.; Johnston, G.A.R. (Sydney Univ. (Australia))


    The GABA analogue baclofen (3-(p-chlorophenyl)-4-aminobutanoic acid) has stereospecific actions on the peripheral and central nervous systems. This paper describes the resolution of tritium-labelled baclofen by high performance liquid chromatography on a reverse-phase C18 column using a chiral mobile phase. The method, which may have general application to certain other GABA analogues, affords optically pure (+)- and (-)-baclofen labelled with tritium to high specific activity suitable for ligand binding and other neurochemical studies.

  13. Separation of proteins from human plasma by sample displacement chromatography in hydrophobic interaction mode


    Josic, Djuro; Breen, Lucas; Clifton, James; Gajdosik, Martina Srajer; Gaso-Sokac, Dajana; Rucevic, Marijana; Müller, Egbert


    Sample displacement chromatography (SDC) in reversed-phase and ion-exchange modes was introduced approximately twenty years ago. This method was first used for the preparative purification of peptides and proteins. Recently, SDC in ion-exchange mode was also successfully used for enrichment of low abundance proteins from human plasma. In this paper, the use of SDC for the separation of plasma proteins in hydrophobic interaction mode is demonstrated. By use of two or more columns coupled in se...

  14. Recent applications of hydrophilic interaction liquid chromatography in pharmaceutical analysis. (United States)

    Zhang, Qian; Yang, Feng-Qing; Ge, Liya; Hu, Yuan-Jia; Xia, Zhi-Ning


    Hydrophilic interaction liquid chromatography, an alternative liquid chromatography mode, is of particular interest in separating hydrophilic and polar ionic compounds. Compared with traditional liquid chromatography techniques, hydrophilic interaction liquid chromatography offers specific advantages mainly including: (1) relatively green and water-soluble mobile phase composition, which enhances the solubility of hydrophilic and polar ionic compounds; (2) no need for ion-pairing reagents and high content of organic solvent, which benefits mass spectrometry detection; (3) high orthogonality to reverse-phase liquid chromatography, well adapted to two-dimensional liquid chromatography for complicated samples. Therefore, hydrophilic interaction liquid chromatography has been rapidly developed in many areas over the past decades. This review summarizes the recent progress (from 2012 to July 2016) of hydrophilic interaction liquid chromatography in pharmaceutical analysis, with the focus on detecting chemical drugs in various matrices, charactering active compounds of natural products and assessing biotherapeutics through typical structure unit. Moreover, the retention mechanism and behavior of analytes in hydrophilic interaction liquid chromatography as well as some novel hydrophilic interaction liquid chromatography columns used for pharmaceutical analysis are also described.

  15. Drying techniques for the visualisation of agarose-based chromatography media by scanning electron microscopy. (United States)

    Nweke, Mauryn C; Turmaine, Mark; McCartney, R Graham; Bracewell, Daniel G


    The drying of chromatography resins prior to scanning electron microscopy is critical to image resolution and hence understanding of the bead structure at sub-micron level. Achieving suitable drying conditions is especially important with agarose-based chromatography resins, as over-drying may cause artefact formation, bead damage and alterations to ultrastructural properties; and under-drying does not provide sufficient resolution for visualization under SEM. This paper compares and contrasts the effects of two drying techniques, critical point drying and freeze drying, on the morphology of two agarose based resins (MabSelect™/dw ≈85 µm and Capto™ Adhere/dw ≈75 µm) and provides a complete method for both. The results show that critical point drying provides better drying and subsequently clearer ultrastructural visualization of both resins under SEM. Under this protocol both the polymer fibers (thickness ≈20 nm) and the pore sizes (diameter ≈100 nm) are clearly visible. Freeze drying is shown to cause bead damage to both resins, but to different extents. MabSelect resin encounters extensive bead fragmentation, whilst Capto Adhere resin undergoes partial bead disintegration, corresponding with the greater extent of agarose crosslinking and strength of this resin. While freeze drying appears to be the less favorable option for ultrastructural visualization of chromatography resin, it should be noted that the extent of fracturing caused by the freeze drying process may provide some insight into the mechanical properties of agarose-based chromatography media.

  16. Determination of phosphite in a eutrophic freshwater lake by suppressed conductivity ion chromatography. (United States)

    Han, Chao; Geng, Jinju; Xie, Xianchuan; Wang, Xiaorong; Ren, Hongqiang; Gao, Shixiang


    The establishment of a sensitive and specific method for the detection of reduced phosphorus (P) is crucial for understanding P cycle. This paper presents the quantitative evidence of phosphite (P, +3) from the freshwater matrix correspondent to the typically eutrophic Lake Taihu in China. By ion chromatography coupled with gradient elution procedure, efficient separation of micromolar levels of phosphite is possible in the presence of millimolar levels of interfering ions, such as chloride, sulfate, and hydrogen carbonate in freshwater lakes. Optimal suppressed ion chromatography conditions include the use of 500 μL injection volumes and an AS11 HC analytical column heated to 30 °C. The method detection limit of 0.002 μM for phosphite was successfully applied for phosphite determination in natural water samples with recoveries ranging from 90.7 ± 3.2% to 108 ± 1.5%. Phosphite in the freshwater matrix was also verified using a two-dimensional capillary ion chromatography and ion chromatography coupled with mass spectrometry. Results confirmed the presence of phosphite in Lake Taihu ranging from 0.01 ± 0.01 to 0.17 ± 0.01 μM, which correlated to 1-10% of the phosphate. Phosphite is an important component of P and may influence biogeochemical P cycle in lakes.

  17. The Role Seemingly of Amorphous Silica Gel Layers in Chiral Separations by Planar Chromatography

    Directory of Open Access Journals (Sweden)

    Teresa Kowalska


    Full Text Available In planar chromatography, silica gel appears as the most frequently used adsorbent. Its preference as planar chromatographic stationary phase is due to its high specific surface area (ca. 700 m2 g-1 and relatively simple active sites (silanol groups, Si-OH. The high specific surface area of silica gel and a high density of coverage of its surface with the silanol active sites contribute jointly to an excellent separation performance of this adsorbent. In our experiments on chiral separation of the enantiomer pairs by planar chromatography, contradictory behavior of the silica gel layers versus the chiral compounds was observed. The migration tracks of chiral compounds in the ascending planar chromatographic mode were not vertical but bent on either side being a function of analyte chirality. This deviation of the analyte’s migration track was noticed, when using the densitometric scanner to quantify the respective chromatograms. In order to confirm the hypothesis as to the microcrystalline nature of silica gel used in liquid chromatography, it was further investigated through circular dichroism (CD and the data thereof confirmed that the ‘chromatographic’ silica gels are not amorphous but microcrystalline, contributing to the (partial horizontal enantioseparation of the antimer pairs. This paper summarizes the results of our investigation on the microcrystalline nature of silica gels used in planar chromatography and their impact on enantioseparation of the selected pairs of antimers.

  18. Paper Chromatography and UV-Vis Spectroscopy to Characterize Anthocyanins and Investigate Antioxidant Properties in the Organic Teaching Laboratory (United States)

    Galloway, Kelli R.; Bretz, Stacey Lowery; Novak, Michael


    A variety of fruits and vegetables, including raspberries, blueberries, Concord grapes, blackberries, strawberries, peaches, eggplant, red cabbage, and red onions, contain flavonoid compounds known as anthocyanins that are responsible for the blue-red color and the astringent taste associated with such foods. In addition, anthocyanins exhibit a…

  19. Determination of Aromatic Amines Released from Azo Dyes in Paper Packaging by Liquid Chromatography-Tandem Mass Spectrometry. (United States)

    Yang, Fei; Bian, Zhaoyang; Li, Zhonghao; Fan, Ziyan; Wang, Ying; Liu, ShanShan; Deng, Huimin; Tang, Gangling


    An LC-tandem MS (LC-MS/MS) method for the determination of 21 kinds of carcinogenic aromatic amines released from azo dyes in food wrappers was used in this research. Sodium dithionite was added to a citric acid buffer medium to reduce and decompose possible azo dyes. The extract was analyzed after liquid-liquid extraction (LLE) and dispersive SPE (d-SPE). The conditions for chromatographic separation, mass spectrum, LLE, and d-SPE were optimized. Under optimal conditions, the LOD was in the range of 0.13-0.35 mg/kg and LOQ in the range of 0.38-1.05 mg/kg, with the addition of standard recoveries of most aromatic amines being ≥80% and RSDs ≤10%. The recoveries for 2,4-diaminotoluene and 2,4-diaminoanisole were significantly lower, being ≤40%. The method was successfully used to analyze 30 practical samples, and the results showed that it is user-friendly, with high sensitivity, rapid control, and low matrix interference.

  20. Human induced pluripotent stem cell-derived beating cardiac tissues on paper. (United States)

    Wang, Li; Xu, Cong; Zhu, Yujuan; Yu, Yue; Sun, Ning; Zhang, Xiaoqing; Feng, Ke; Qin, Jianhua


    There is a growing interest in using paper as a biomaterial scaffold for cell-based applications. In this study, we made the first attempt to fabricate a paper-based array for the culture, proliferation, and direct differentiation of human induced pluripotent stem cells (hiPSCs) into functional beating cardiac tissues and create "a beating heart on paper." This array was simply constructed by binding a cured multi-well polydimethylsiloxane (PDMS) mold with common, commercially available paper substrates. Three types of paper material (print paper, chromatography paper and nitrocellulose membrane) were tested for adhesion, proliferation and differentiation of human-derived iPSCs. We found that hiPSCs grew well on these paper substrates, presenting a three-dimensional (3D)-like morphology with a pluripotent property. The direct differentiation of human iPSCs into functional cardiac tissues on paper was also achieved using our modified differentiation approach. The cardiac tissue retained its functional activities on the coated print paper and chromatography paper with a beating frequency of 40-70 beats per min for up to three months. Interestingly, human iPSCs could be differentiated into retinal pigment epithelium on nitrocellulose membrane under the conditions of cardiac-specific induction, indicating the potential roles of material properties and mechanical cues that are involved in regulating stem cell differentiation. Taken together, these results suggest that different grades of paper could offer great opportunities as bioactive, low-cost, and 3D in vitro platforms for stem cell-based high-throughput drug testing at the tissue/organ level and for tissue engineering applications.

  1. Isotopic separation by ion chromatography; La separation isotopique par chromatographie ionique

    Energy Technology Data Exchange (ETDEWEB)

    Albert, M.G.; Barre, Y.; Neige, R. [CEA Centre d`Etudes de la Vallee du Rhone, 26 - Pierrelatte (France). Dept. de Technologie de l`Enrichissement


    The isotopic exchange reaction and the isotopic separation factor are first recalled; the principles of ion chromatography applied to lithium isotope separation are then reviewed (displacement chromatography) and the process is modelled in the view of dimensioning and optimizing the industrial process; the various dimensioning parameters are the isotopic separation factor, the isotopic exchange kinetics and the material flow rate. Effects of the resin type and structure are presented. Dimensioning is also affected by physico-chemical and hydraulic parameters. Industrial implementation features are also discussed. 1 fig., 1 tab., 5 refs.


    The paper discusses the analysis of trace-level organic combustion process emissions using novel multidimensional gas chromatography-mass spectrometry (MDGC-MS) procedures. It outlines the application of the technique through the analyses of various incinerator effluent and produ...

  3. Analyzing Inquiry Questions of High-School Students in a Gas Chromatography Open-Ended Laboratory Experiment (United States)

    Blonder, Ron; Mamlock-Naaman, Rachel; Hofstein, Avi


    This paper describes the implementation of an open-ended inquiry experiment for high-school students, based on gas chromatography (GC). The research focuses on identifying the level of questions that students ask during the GC open inquiry laboratory, and it examines whether implementing the advanced inquiry laboratory opens up new directions for…

  4. Selective enrichment of sialic acid-containing glycopeptides using titanium dioxide chromatography with analysis by HILIC and mass spectrometry

    DEFF Research Database (Denmark)

    Palmisano, Giuseppe; Lendal, Sara Eun; Engholm-Keller, Kasper


    of glycosylation sites and the characterization of glycan structures. In this paper, we describe a protocol for the selective enrichment of SA-containing glycopeptides using a combination of titanium dioxide (TiO(2)) and hydrophilic interaction liquid chromatography (HILIC). The selectivity of TiO(2) toward SA...

  5. Trends in High Performance Liquid Chromatography for Cultural Heritage. (United States)

    Degano, Ilaria; La Nasa, Jacopo


    The separation, detection and quantitation of specific species contained in a sample in the field of Cultural Heritage requires selective, sensitive and reliable methods. Procedures based on liquid chromatography fulfil these requirements and offer a wide range of applicability in terms of analyte types and concentration range. The main applications of High Performance Liquid Chromatography in this field are related to the separation and detection of dyestuffs in archaeological materials and paint samples by reversed-phase liquid chromatography with suitable detectors. The relevant literature will be revised, with particular attention to sample treatment strategies and future developments. Reversed phase chromatography has also recently gained increasing importance in the analysis of lipid binders and lipid materials in archaeological residues: the main advantages and disadvantages of the new approaches will be discussed. Finally, the main applications of ion chromatography and size exclusion chromatography in the field of Cultural Heritage will be revised in this chapter.

  6. Wind Speed Measurement by Paper Anemometer (United States)

    Zhong, Juhua; Cheng, Zhongqi; Guan, Wenchuan


    A simple wind speed measurement device, a paper anemometer, is fabricated based on the theory of standing waves. In providing the working profile of the paper anemometer, an experimental device is established, which consists of an anemometer sensor, a sound sensor, a microphone, paper strips, a paper cup, and sonic acquisition software. It shows…

  7. 21 CFR 872.6140 - Articulation paper. (United States)


    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Articulation paper. 872.6140 Section 872.6140 Food... DEVICES DENTAL DEVICES Miscellaneous Devices § 872.6140 Articulation paper. (a) Identification. Articulation paper is a device composed of paper coated with an ink dye intended to be placed between...

  8. 27 CFR 40.351 - Cigarette papers. (United States)


    ... 27 Alcohol, Tobacco Products and Firearms 2 2010-04-01 2010-04-01 false Cigarette papers. 40.351... OF THE TREASURY (CONTINUED) TOBACCO MANUFACTURE OF TOBACCO PRODUCTS, CIGARETTE PAPERS AND TUBES, AND PROCESSED TOBACCO Manufacture of Cigarette Papers and Tubes Taxes § 40.351 Cigarette papers....

  9. 27 CFR 41.34 - Cigarette papers. (United States)


    ... 27 Alcohol, Tobacco Products and Firearms 2 2010-04-01 2010-04-01 false Cigarette papers. 41.34... OF THE TREASURY (CONTINUED) TOBACCO IMPORTATION OF TOBACCO PRODUCTS, CIGARETTE PAPERS AND TUBES, AND PROCESSED TOBACCO Taxes Tax Rates § 41.34 Cigarette papers. Cigarette papers are taxed at the...

  10. Advances in Application of Chromatography and Chromatography- Mass Spectrometry in Analysis of Traditional Chinese Medicine%色谱及色谱-质谱联用技术在中药分析中的应用进展

    Institute of Scientific and Technical Information of China (English)

    张晶; 杨海龙; 臧恒昌


    The advances in the application of chromatography and chromatography- mass spectrometry in the analysis of traditional Chinese medicine (TCM) are reviewed in this paper. Characteristics, range of application and research status of each method are elaborated, which aim to provide reference for TCM researchers.%  对色谱及其质谱联用技术在中药领域的应用进展做一综述,阐述了各方法的特点、应用范围及研究现状,旨在为中药研究工作者提供参考依据。

  11. Paper-based batteries: a review. (United States)

    Nguyen, Thu H; Fraiwan, Arwa; Choi, Seokheun


    There is an extensively growing interest in using paper or paper-like substrates for batteries and other energy storage devices. Due to their intrinsic characteristics, paper (or paper-like) batteries show outstanding performance while retaining low cost, multifunctionality, versatility, flexibility and disposability. In this overview, we review recent achievements in paper (or paper-like) batteries as well as their applications. Various types of paper power devices are discussed including electrochemical batteries, biofuel cells, lithium-ion batteries, supercapacitors, and nanogenerators. Further scientific and technological challenges in this field are also discussed.

  12. High Performance Liquid Chromatography/Video Fluorometry. Part II. Applications. (United States)


    HIGH PERFORMANCE LIQUID CHROMATOGRAPHY /VIDEO FLUOROMETRY. PART...REP«T_N&:-ŗ/ High Performance Liquid Chromatography /Video Fluorometry» Part II. Applications« by | Dennis C./Shelly* Michael P./Vogarty and...Data EnlirtdJ REPORT DOCUMENTATION PAGE t. REPORT NUMBER 2 GOVT ACCESSION NO 4. T1TI.F (and Submit) lP-^fffsyva High Performance Liquid Chromatography

  13. Separation of proteins by simulated moving bed chromatography


    Houwing, J.


    This thesis describes the use of simulated moving bed (SMB) chromatography for separation of proteins. The underlying aim is the increase of the efficiency of process chromatography in terms of a reduction of the sorbent and buffer consumption in comparison to fixed bed chromatography. Both size exclusion and ion exchange separations of synthetic mixtures of proteins are considered. The main topics covered are the selection of the liquid to sorbent flow rate ratios, mass transfer effects and ...

  14. Tutorial: simulating chromatography with Microsoft Excel Macros. (United States)

    Kadjo, Akinde; Dasgupta, Purnendu K


    Chromatography is one of the cornerstones of modern analytical chemistry; developing an instinctive feeling for how chromatography works will be invaluable to future generation of chromatographers. Specialized software programs exist that handle and manipulate chromatographic data; there are also some that simulate chromatograms. However, the algorithm details of such software are not transparent to a beginner. In contrast, how spreadsheet tools like Microsoft Excel™ work is well understood and the software is nearly universally available. We show that the simple repetition of an equilibration process at each plate (a spreadsheet row) followed by discrete movement of the mobile phase down by a row, easily automated by a subroutine (a "Macro" in Excel), readily simulates chromatography. The process is readily understood by a novice. Not only does this permit simulation of isocratic and simple single step gradient elution, linear or multistep gradients are also easily simulated. The versatility of a transparent and easily understandable computational platform further enables the simulation of complex but commonly encountered chromatographic scenarios such as the effects of nonlinear isotherms, active sites, column overloading, on-column analyte degradation, etc. These are not as easily simulated by available software. Views of the separation as it develops on the column and as it is seen by an end-column detector are both available in real time. Excel 2010™ also permits a 16-level (4-bit) color gradation of numerical values in a column/row; this permits visualization of a band migrating down the column, much as Tswett may have originally observed, but in a numerical domain. All parameters of relevance (partition constants, elution conditions, etc.) are readily changed so their effects can be examined. Illustrative Excel spreadsheets are given in the Supporting Information; these are easily modified by the user or the user can write his/her own routine.

  15. Selected papers for global `95 concerning plutonium

    Energy Technology Data Exchange (ETDEWEB)

    Sutcliffe, W.G. [ed.


    This report contains selected papers from the Global `95 Conference ``Evaluation of Emerging Nuclear Fuel Cycle Systems,`` held in Versailles, Sept. 11-14, 1995. The 11 papers in Part I are from ``Benefits and Risks of Reprocessing`` sessions. The 7 papers in Part II are some of the more interesting poster papers that relate to the use of Pu for power generation. Finally, the 3 papers are on the topic of management and disposition of Pu from retired nuclear weapons.

  16. Extraction and chromatography of carotenoids from pumpkin. (United States)

    Seo, Jung Sook; Burri, Betty Jane C; Quan, Zhejiu; Neidlinger, Terry R


    Vitamin A deficiency is a health problem in Southeast Asia that can be corrected by feeding orange fruits and vegetables such as mango. Pumpkin is a traditional Korean food that is easy to store and is already believed to have health benefits. We extracted carotenoids from pumpkin by liquid-liquid extraction and by supercritical fluid extraction. We measured carotenoids by reversed-phase chromatography with diode array detection. The major carotenoid in pumpkin (> 80%) is beta-carotene, with lesser amounts of lutein, lycopene, alpha-carotene and cis-beta-carotene. Pumpkin is a rich source of beta-carotene and might be useful for preventing Vitamin A deficiency.

  17. Affinity chromatography with an immobilized RNA enzyme.


    Vioque, A; Altman, S


    M1 RNA, the catalytic subunit of Escherichia coli RNase P, has been covalently linked at its 3' terminus to agarose beads. Unlike M1 RNA, which is active in solution in the absence of the protein component (C5) of RNase P, the RNA linked to the beads is active only in the presence of C5 protein. Affinity chromatography of crude extracts of E. coli on a column prepared from the beads to which the RNA has been crosslinked results in the purification of C5 protein in a single step. The protein h...

  18. Separation of Proteins by Electrophoretic Affinity Chromatography

    Institute of Scientific and Technical Information of China (English)

    邺韶骅; 刘铮; 丁富新; 袁乃驹


    A new kind of electrophoretic affinity chromatography (EAC) for bioseparation was proposed,Separation by EAC was conducted in a multicompartment electrolyzer in which the affinity gel media were packed in one of the central compartments.The presence of an electric field accelerated the migration of proteins inside the gel matrix during adsorption and descrption processes,This led to the increase of the overall speed of separation,The present study was focused on the effect of the strength of the electric field on adsorption and desorption processes.

  19. Course on Advanced Analytical Chemistry and Chromatography

    DEFF Research Database (Denmark)

    Andersen, Jens Enevold Thaulov; Fristrup, Peter; Nielsen, Kristian Fog


    Methods of analytical chemistry constitute an integral part of decision making in chemical research, and students must master a high degree of knowledge, in order to perform reliable analysis. At DTU departments of chemistry it was thus decided to develop a course that was attractive to master...... students of different direction of studies, to Ph.D. students and to professionals that need an update of their current state of skills and knowledge. A course of 10 ECTS points was devised with the purpose of introducing students to analytical chemistry and chromatography with the aim of including theory...

  20. Phosphopeptide enrichment by immobilized metal affinity chromatography

    DEFF Research Database (Denmark)

    Thingholm, Tine E.; Larsen, Martin R.


    Immobilized metal affinity chromatography (IMAC) has been the method of choice for phosphopeptide enrichment prior to mass spectrometric analysis for many years and it is still used extensively in many laboratories. Using the affinity of negatively charged phosphate groups towards positively...... charged metal ions such as Fe3+, Ga3+, Al3+, Zr4+, and Ti4+ has made it possible to enrich phosphorylated peptides from peptide samples. However, the selectivity of most of the metal ions is limited, when working with highly complex samples, e.g., whole-cell extracts, resulting in contamination from...

  1. [Recent advances in capillary scale ion chromatography technology]. (United States)

    Yang, Bingcheng; Diao, Xuefang


    Ion chromatography (IC) has been a well-established technique for the analysis of ionic samples. The aqueous solution used for IC eluent is well suited for bioanalysis in relative to common liquid chromatography. This is especially true for capillary ion chromatography (CIC) due to its advantage of small sample needed. CIC is generally divided into three categories including open tubular, packed and monolithic. In this review, the recent progress of CIC is summarized based on the development of several key components associated with packed column-based system. The development of open tubular ion chromatography is also reviewed.

  2. Separation and Detection of Ceramides by HPLC Followed by Evaporative Light-Scattering Detection and Thin Layer Chromatography

    Institute of Scientific and Technical Information of China (English)

    张琳; 周全; 傅学奇; 陈国强


    Ceramides are important signaling molecules involved in a variety of cellular processes, including cell growth, differentiation, and apoptosis. Currently, different methods are used for ceramide analysis, some of which are insensitive or cumbersome. This paper described methods utilizing thin layer chromatography (TLC) and high-performance liquid chromatography (HPLC) followed by evaporative light scattering detection (ELSD) to detect ceramide directly in cell extracts without derivatization, which was proved to be efficient and reproducible. Five kinds of ceramides were used as standards. Both TLC and normal-phase HPLC/ELSD results indicate that yeast contains several kinds of ceramides.

  3. The weight of flash chromatography: A tool to predict its mass intensity from thin-layer chromatography

    Directory of Open Access Journals (Sweden)

    Freddy Pessel


    Full Text Available Purification by flash chromatography strongly impacts the greenness of a process. Unfortunately, due to the lack of the relevant literature data, very often this impact cannot be assessed thus preventing the comparison of the environmental factors affecting the syntheses. We developed a simple mathematical approach to evaluate the minimum mass intensity of flash chromatography from the retention factor values determined by thin-layer chromatography.

  4. Recent Research and Development of Monolithic Column in Ion Chromatography%整体柱离子色谱的研究进展

    Institute of Scientific and Technical Information of China (English)

    陈倩; 于泓


    Monolithic columns have been employed in low pressure, fast and high efficient separation, for their many excellent characteristics. When applied to ion chromatography field, monolithic columns can achieve more effective analysis than traditional columns. Therefore, the method of ion chromatography based on monolithic columns attracts increasing interests. In this paper, the sorts of ion chromatography, classification of monolithic stationary phases, preparation ways of monolithic columns, performances and features of monolithic columns were introduced. The application of conventional monolithic columns in ion chromatography and the utilization of capillary monolithic columns in capillary ion chromatography were summarized according to the different assortments and properties of monolithic columns and ion chromatography, which included silica-based monolithic stationary phase and organic polymer-based monolithic stationary phase. The development of ion chromatography based on monolithic columns in the future was reviewed and prospected.%该文介绍了离子色谱的分类,整体柱的分类、制备及特点,并以此为依据归纳总结了常规整体柱在离子色谱中的应用和毛细管整体柱在毛细管离子色谱中的应用,其中包括硅胶基质整体柱和聚合物基质整体柱,评述并展望了整体柱离子色谱的发展前景.

  5. 2009 Annual Report of China's Paper Industry

    Institute of Scientific and Technical Information of China (English)


    @@ Ⅰ.Production and Consumption of Paper & Board 1.The General Situation of 2009According to the survey made by China Paper Association,in 2009,there were about 3,700 paper & board manufacturers; their total production of paper & board was86.40 million tons,increased by 8.27% compared to 79.80million tons in 2008; the total paper & board consumption was 85.69 million tons,increased by 7.99% compared to 79.35 million tons in 2008;paper & board per capita consumption was 64 kg,increased 4 kg.

  6. 2007 Annual Report of China's Paper Industry

    Institute of Scientific and Technical Information of China (English)

    China Paper Association


    @@ 1.Production and consumption of paper and board 1. According to the survey made by China Paper Association,CPA, in 2007, there were about 3500 paper mills of China'spaper industry; their total output of paper & board was 73.50 million tons, increased by 13.08% compared with 65.00 mil-lion tons in 2006; the total paper & board consumption was72.90 million tons, increased by 10.45% compared with 66.00 million tons in 2006; paper & board per capita consumption reached 55 kg from 50 kg in 2006.

  7. Experimental design in chromatography: a tutorial review. (United States)

    Hibbert, D Brynn


    The ability of a chromatographic method to successful separate, identify and quantitate species is determined by many factors, many of which are in the control of the experimenter. When attempting to discover the important factors and then optimise a response by tuning these factors, experimental design (design of experiments, DoE) gives a powerful suite of statistical methodology. Advantages include modelling by empirical functions, not requiring detailed knowledge of the underlying physico-chemical properties of the system, a defined number of experiments to be performed, and available software to accomplish the task. Two uses of DoE in chromatography are for showing lack of significant effects in robustness studies for method validation, and for identifying significant factors and then optimising a response with respect to them in method development. Plackett-Burman designs are widely used in validation studies, and fractional factorial designs and their extensions such as central composite designs are the most popular optimisers. Box-Behnken and Doehlert designs are becoming more used as efficient alternatives. If it is not possible to practically realise values of the factors required by experimental designs, or if there is a constraint on the total number of experiments that can be done, then D-optimal designs can be very powerful. Examples of the use of DoE in chromatography are reviewed. Recommendations are given on how to report DoE studies in the literature.

  8. Simulating retention in gas-liquid chromatography

    Energy Technology Data Exchange (ETDEWEB)

    Martin, M.G.; Siepmann, J.I.; Schure, M.R.


    Accurate predictions of retention times, retention indices, and partition constants are a long sought-after goal for theoretical studies in chromatography. Configurational-bias Monte Carlo (CBMC) simulations in the Gibbs ensemble using the transferable potentials for phase equilibria-united atom (TraPPE-UA) force field have been carried out to obtain a microscopic picture of the partitioning of 10 alkane isomers between a helium vapor phase and a squalane liquid phase, a protypical gas-liquid chromatography system. The alkane solutes include some topological isomers that differ only in the arrangement of their building blocks (e.g., 2,5-dimethylhexane and 3,4-dimethylhexane), for which the prediction of the retention order is particularly difficult. The Kovats retention indices, a measure of the relative retention times, are calculated directly from the partition constants and are in good agreement with experimental values. The calculated Gibbs free energies of transfer for the normal alkanes conform to Martin's equation which is the basis of linear free energy relationships used in many process modeling packages. Analysis of radial distribution functions and the corresponding energy integrals does not yield evidence for specific retention structures and shows that the internal energy of solvation is not the main driving force for the separation of topological isomers in this system.

  9. Cannabis (marijuana) contamination of United States and foreign paper currency. (United States)

    Lavins, Eric S; Lavins, Bethany D; Jenkins, Amanda J


    It is well known that United States paper currency in general circulation is contaminated with trace amounts of illicit substances such as cocaine, heroin and marijuana. As is the case with cocaine, differentiating "background levels" of the various cannabinoid constituents of Cannabis sativa L., namely, Delta(9)-tetrahydrocannabinol (THC), cannabinol (CBN), and cannabidiol (CBD) contaminating currency found in the general circulation from currency associated with illegal drug activity is imperative if a legal nexus is to be established with the latter. We analyzed 165 randomly collected paper currency notes from 12 U.S. cities (N = 125) and 4 foreign countries (N = 40) for THC, CBD, CBN, 11-nor-9-carboxy-Delta(9)-tetrahydrocannabinol, and 11-hydroxy-Delta(9)-tetrahydrocannabinol. Uncirculated US 1 dollar notes were added as negative controls. Drug residues were washed from individual bills, extracted using a liquid-liquid extraction protocol, derivatized, and quantitated by gas chromatography-mass spectrometry by selected ion monitoring. For the US 1 dollar currency, THC was present in 1.6% (2 notes), CBN 10.31% (13 notes), CBD 1.6% (2 notes). The following concentrations were determined: 0.085 microg/bill and 0.146 microg/bill for THC; 0.014-0.774 microg/bill (mean 0.166 microg/bill) for CBN; and 0.032 microg/bill and 0.086 microg/bill for CBD. For the foreign currency (Colombia, Qatar, India, and New Zealand), THC and CBN were present in 22.5% (9 notes). The following concentration ranges were determined: THC 0.026-0.065 microg/bill (mean 0.049 microg/bill), CBN 0.061-0.197 microg/bill (mean 0.115 microg/bill). All of the positive THC and CBN were found in the New Zealand polypropylene notes. This study demonstrated that marijuana (cannabinoids) may contaminate both paper and plastic currency.

  10. Matrix influences on the determination of common ions by using ion chromatography part 1--determination of inorganic anions. (United States)

    Michalski, Rajmund; Lyko, Aleksandra; Kurzyca, Iwona


    Ion chromatography is the most popular instrumental analytical method used for the determination of anions and cations in water and wastewater. Isocratic ion chromatography with suppressed conductivity detection is frequently used in laboratories carrying out routine analyses of inorganic anions. The paper presents the results of the research into the influence of selected inorganic anions dominant in environmental samples (Cl(-), NO(3)(-), SO(4)(2-)) on the possibility of simultaneous determination of F(-), Cl(-), NO(2)(-), NO(3)(-), PO(4)(3-) and SO(4)(2-) with the application of this most popular ion chromatography type in standard separation conditions. Four Dionex and four Metrohm anion-exchange columns were tested in standard separation conditions recommended by their manufacturers with both standard solutions and environmental samples with complex matrix.

  11. Printability of Synthetic Papers by Electrophotography

    Directory of Open Access Journals (Sweden)

    Rozália Szentgyörgyvölgyi


    Full Text Available This paper deals with the printability of synthetic papers by the electrophotography technique. Prints of cmyk colour fields from 20% to 100% raster tone values were printed on three types of synthetic papers (one film synthetic paper and two fiber synthetic papers. The investigation of the appearance included densitometric measurement of the cmyk prints. The results have shown differences in the optical density and optical tone value between cmyk prints made on various synthetic papers. The highest optical density and the increase of the optical tone value were observed on the film synthetic paper, where cmyk prints were more saturated. The highest abrasion resistance of cmyk prints was obtained from the fibre synthetic paper.

  12. Remote Sensing Best Paper Award 2013


    Prasad Thenkabail


    Remote Sensing has started to institute a “Best Paper” award to recognize the most outstanding papers in the area of remote sensing techniques, design and applications published in Remote Sensing. We are pleased to announce the first “Remote Sensing Best Paper Award” for 2013. Nominations were selected by the Editor-in-Chief and selected editorial board members from among all the papers published in 2009. Reviews and research papers were evaluated separately.

  13. Visualization According To Research Paper Keywords


    Isenberg, Petra; Isenberg, Tobias; Sedlmair, Michael; Chen, Jian; Möller, Torsten


    To appear; International audience; We analyzed visualization paper keywords supplied for 4366 papers accepted to three main visualization conferences. We describe main keywords, topic areas, and 10-year historic trends from author-chosen keywords for papers published in the IEEE Visualization conference series (now called IEEE VIS) since 2004. Furthermore, we present the KeyVis Web application that allows visualization researchers to easily browse the 2600+ keywords used for IEEE VIS papers o...

  14. Mathematical modelling of paper degradation in books


    Nimmo, A J


    Paper cannot be prevented from degrading and does not necessarily degrade uniformly across its volume. It has been established that as paper degrades, VOCs (Volatile Organic Compounds) are produced. This body of work studies paper degradation with respect to the role VOCs play. The thesis investigates how a VOC a ecting the paper's acidity can in turn a ect the degradation rate and through modelling the VOC concentration pro le, the degradation pro le is found. To create the model from a chem...

  15. Guinea-Bissau; Poverty Reduction Strategy Paper


    International Monetary Fund


    This paper presents an overview of the National Poverty Reduction Strategy Paper (NPRSP) for Guinea-Bissau. The paper discusses the phenomenon of poverty, its dimensions, extent, and distribution by category and region. It provides a background analysis of developments in poverty based on the diagnostic of past economic policies. The paper presents the priority goals in the fight against poverty by articulating a long-term and medium-term vision as well as strategic actions. The operational s...

  16. 76 FR 42730 - Paper Clips From China (United States)


    ... COMMISSION Paper Clips From China Determination On the basis of the record \\1\\ developed in the subject five... order on paper clips from China would be likely to lead to continuation or recurrence of material injury... Publication 4242 (July 2011), entitled Paper Clips from China: Investigation No. 731-TA-663 (Third Review)....

  17. 75 FR 5115 - Tissue Paper From China (United States)


    ... COMMISSION Tissue Paper From China AGENCY: United States International Trade Commission. ACTION: Institution of a five-year review concerning the antidumping duty order on certain tissue paper products from... antidumping duty order on certain tissue paper products from China would be likely to lead to continuation...

  18. Common mistakes in writing a scientific paper

    Directory of Open Access Journals (Sweden)

    Militon Frentiu


    Full Text Available As editors of Studia UBB Informatica we have noticed that many papers contains some frequent errors. The best way to change this situation, to improve the quality of Studia papers, is to underline these frequent errors. And also, to offer a guide for writing papers for the Studia UBB Informatica journal, which we have done.

  19. Integrating Electronics and Microfluidics on Paper. (United States)

    Hamedi, Mahiar M; Ainla, Alar; Güder, Firat; Christodouleas, Dionysios C; Fernández-Abedul, M Teresa; Whitesides, George M


    Paper microfluidics and printed electronics have developed independently, and are incompatible in many aspects. Monolithic integration of microfluidics and electronics on paper is demonstrated. This integration makes it possible to print 2D and 3D fluidic, electrofluidic, and electrical components on paper, and to fabricate devices using them.

  20. Misery Needs Company: The Group Paper. (United States)

    Pomper, Marlene M.

    Many students consider the writing of papers to be a lonely, difficult, and even painful process. To enable these students to improve their essays and research papers, a teacher has used a collaborative method of writing called the group paper. This method encompasses the various stages of writing, from freewriting of first drafts through multiple…

  1. Accountability: Papers from master theses 2009

    NARCIS (Netherlands)

    C.D. Knoops (Chris); J. Noeverman (Jan)


    textabstractLast year, we presented the book “Accountability 2008: papers from master theses”. The book contained eleven papers. Each paper was based on a thesis in the field of Accounting, Auditing and Control, on which these students received a Master’s degree in Economics & Business from the Eras

  2. Computers & Chemical Engineering: Best paper of 2009

    DEFF Research Database (Denmark)

    Venkatasubramanian, Venkat; Gani, Rafiqul


    The Editorial Advisory Board of the Journal has assessed the papers published in Volume 33 by means of a three stage process of nomination and balloting. We are pleased to announce that the 2009 Best Paper of the Year Award goes to J.M. Harrold and R.S. Parker for their paper entitled “Clinically...

  3. 12 CFR 541.5 - Commercial paper. (United States)


    ... 12 Banks and Banking 5 2010-01-01 2010-01-01 false Commercial paper. 541.5 Section 541.5 Banks and Banking OFFICE OF THRIFT SUPERVISION, DEPARTMENT OF THE TREASURY DEFINITIONS FOR REGULATIONS AFFECTING FEDERAL SAVINGS ASSOCIATIONS § 541.5 Commercial paper. The term commercial paper means any note, draft,...

  4. 7 CFR 51.1240 - Paper ends. (United States)


    ... 7 Agriculture 2 2010-01-01 2010-01-01 false Paper ends. 51.1240 Section 51.1240 Agriculture Regulations of the Department of Agriculture AGRICULTURAL MARKETING SERVICE (Standards, Inspections, Marketing... Standards for Cleaned Virginia Type Peanuts in the Shell Definitions § 51.1240 Paper ends. Paper ends...

  5. 49 CFR 174.24 - Shipping papers. (United States)


    ... 49 Transportation 2 2010-10-01 2010-10-01 false Shipping papers. 174.24 Section 174.24... Requirements § 174.24 Shipping papers. (a) A person may not accept a hazardous material for transportation or transport a hazardous material by rail unless that person receives a shipping paper prepared in...

  6. 49 CFR 177.817 - Shipping papers. (United States)


    ... 49 Transportation 2 2010-10-01 2010-10-01 false Shipping papers. 177.817 Section 177.817... Information and Regulations § 177.817 Shipping papers. (a) General requirements. A person may not accept a... received a shipping paper prepared in accordance with part 172 of this subchapter or the material...

  7. 49 CFR 176.24 - Shipping papers. (United States)


    ... 49 Transportation 2 2010-10-01 2010-10-01 false Shipping papers. 176.24 Section 176.24... Requirements § 176.24 Shipping papers. (a) A person may not accept a hazardous material for transportation or transport a hazardous material by vessel unless that person has received a shipping paper prepared...

  8. Demonstrating Fluorescence with Neon Paper and Plastic (United States)

    Birriel, Jennifer J.; Roe, Clarissa


    Several papers in this journal have dealt with the fluorescence in orange neon plastic, olive oil, and soda. In each case, the fluorescent emission was excited by either green or violet-blue laser light. In this paper, we examine the fluorescent emission spectra of so-called neon colored papers and plastic clipboards available in department and…

  9. 76 FR 171 - Paper Clips From China (United States)


    ... COMMISSION Paper Clips From China AGENCY: United States International Trade Commission. ACTION: Institution of a five-year review concerning the antidumping duty order on paper clips from China. SUMMARY: The... on paper clips from China would be likely to lead to continuation or recurrence of material...

  10. Focus on China's Paper Industry

    Institute of Scientific and Technical Information of China (English)


    In the English section of this issue, 〈China Paper Newsletter〉 will introduce" the Twelfth Five-Year Plan of China's Paper Industry"," 2011 Annual Report of China's Paper Industry", and news of projects.

  11. 光色谱的进展%Development of Optical Chromatography

    Institute of Scientific and Technical Information of China (English)

    顾峻岭; 傅若农


    光色谱是近年来发展起来的利用辐射力和介质流体分离粒子的新技术,在分离和测定粒子大小及生物化学研究中有较大的应用潜力。本文对光色谱的理论、应用进展进行综述。%Optical chromatography is a new separation and determination technique of particales. It has great potential value in the separation and determination of particales. The development, basic theory and application of optical chromatography are reviewed in this paper.

  12. Isolation of deoxypodophyllotoxin and podophyllotoxin from Juniperus sabina by high speed counter current chromatography

    Energy Technology Data Exchange (ETDEWEB)

    Zhao, Y.; Yang, Y.; Chen, Q.; Kasimu, R.; Aisa, H.A.


    Deoxypodophyllotoxin and podophyllotoxin are known for their excellent anti-proliferative and anti-tumor activities, therefore large amount of pure compounds is urgently needed as authentic standards for various in vivo and in vitro studies. In this paper, an effective, rapid separation and purification method of deoxypodophyllotoxin and podophyllotoxin from the crude extract of Juniperus sabina was established using high speed counter current chromatography (HSCCC). HSCCC was performed with atwo phase solvent system comprising of n-hexane-ethylacetate-methanol-water (3:5:3:5, v/v) at the flow rate of 2mL/min at the speed of 850 rpm. 34.8 mg of deoxypodophyllotoxin and 7.9 mg of podophyllotoxin were obtained from 200 mg crude sample with a purity of 96.5% and 94.4%, respectively, as determined by high performance liquid chromatography (HPLC). (Author)

  13. 现代液相色谱进展%Progress of Modern Liquid Chromatography

    Institute of Scientific and Technical Information of China (English)

    韩南银; 王利生; 傅若农


      本文在查阅大量文献的基础上从液相色谱的发展史、固定相、流动相以及检测器四个方面综述了液相色谱的进展,对了解液相色谱的新进展有着重要参考价值。%  The paper dealed with the progress of developing history, stationary phases, fluid phases and detectors of liquid chromatography. It has important reference values for chemists to learn the new progress of modern liquid chromatography in the field of chemistry.

  14. Persistent paper: the myth of "going paperless". (United States)

    Dykstra, Richard H; Ash, Joan S; Campbell, Emily; Sittig, Dean F; Guappone, Ken; Carpenter, James; Richardson, Joshua; Wright, Adam; McMullen, Carmit


    How does paper usage change following the introduction of Computerized Physician Order Entry and the Electronic Medical Record (EMR/CPOE)? To answer that question we analyzed data collected from fourteen sites across the U.S. We found paper in widespread use in all institutions we studied. Analysis revealed psychological, ergonomic, technological, and regulatory reasons for the persistence of paper in an electronic environment. Paper has unique attributes allowing it to fill gaps in information timeliness, availability, and reliability in pursuit of improved patient care. Creative uses have led to "better paper."

  15. Pen-and-Paper User Interfaces

    CERN Document Server

    Steimle, Jurgen


    Even at the beginning of the 21st century, we are far from becoming paperless. Pen and paper is still the only truly ubiquitous information processing technology. Pen-and-paper user interfaces bridge the gap between paper and the digital world. Rather than replacing paper with electronic media, they seamlessly integrate both worlds in a hybrid user interface. Classical paper documents become interactive. This opens up a huge field of novel computer applications at our workplaces and in our homes. This book provides readers with a broad and extensive overview of the field, so as to provide a fu

  16. Electronic Paper:Concept and Expectations

    Institute of Scientific and Technical Information of China (English)

    Makoto Omodani


    The expectations for electronic paper can be summarized as flexibility, readability, and multi-functionality. It focuses on the goal of readability. Paper-like readability should be accepted as the most important target of electronic paper. A concept of readable electronic paper is proposed, and its expected properties, style variations, applications, and various candidate technologies are summarized. As an indication of the realization of readability, an evaluation of user comfort when conducting reading tasks on paper and an LCD shows that free handling of the medium is an important factor in achieving excellent readability.

  17. Analysis of Tocopherols by High Performance Liquid Chromatography


    Edison, B.


    : Gas chromatography is the key technique for organic components and also for tocopherols analysis. High performance liquid chromatography has an important role to take part in applications such as the handling of less usual samples, prevention of degradation of heat sensitive functional groups and for micro preparative purposes. Many approaches for development of improved methods are suggested, especially for reversed phase applications.

  18. Forensic potential of comprehensive two-dimensional gas chromatography

    NARCIS (Netherlands)

    Sampat, A.; Lopatka, M.; Sjerps, M.; Vivo-Truyols, G.; Schoenmakers, P.; van Asten, A.


    In this study, the application of comprehensive two-dimensional (2D) gas chromatography (GC × GC) in forensic science is reviewed. The peer-reviewed publications on the forensic use of GC × GC and 2D gas chromatography with mass spectrometric detection (GC × GC-MS) have been studied in detail, not o

  19. Thin-Layer Chromatography: Four Simple Activities for Undergraduate Students. (United States)

    Anwar, Jamil; And Others


    Presents activities that can be used to introduce thin-layer chromatography at the undergraduate level in relatively less developed countries and that can be performed with very simple and commonly available apparati in high schools and colleges. Activities include thin-layer chromatography with a test-tube, capillary feeder, burette, and rotating…

  20. Using Ion Exchange Chromatography to Separate and Quantify Complex Ions (United States)

    Johnson, Brian J.


    Ion exchange chromatography is an important technique in the separation of charged species, particularly in biological, inorganic, and environmental samples. In this experiment, students are supplied with a mixture of two substitution-inert complex ions. They separate the complexes by ion exchange chromatography using a "flash"…

  1. Bacteria-powered battery on paper. (United States)

    Fraiwan, Arwa; Choi, Seokheun


    Paper-based devices have recently emerged as simple and low-cost paradigms for fluid manipulation and analytical/clinical testing. However, there are significant challenges in developing paper-based devices at the system level, which contain integrated paper-based power sources. Here, we report a microfabricated paper-based bacteria-powered battery that is capable of generating power from microbial metabolism. The battery on paper showed a very short start-up time relative to conventional microbial fuel cells (MFCs); paper substrates eliminated the time traditional MFCs required to accumulate and acclimate bacteria on the anode. Only four batteries connected in series provided desired values of current and potential to power an LED for more than 30 minutes. The battery featured (i) a low-cost paper-based proton exchange membrane directly patterned on commercially available parchment paper and (ii) paper reservoirs for holding the anolyte and the catholyte for an extended period of time. Based on this concept, we also demonstrate the use of paper-based test platforms for the rapid characterization of electricity-generating bacteria. This paper-based microbial screening tool does not require external pumps/tubings and represents the most rapid test platform (<50 min) compared with the time needed by using traditional screening tools (up to 103 days) and even recently proposed MEMS arrays (< 2 days).

  2. Fast centrifugal partition chromatography as a preparative-scale separation technique for citrus flavones (United States)

    Fast centrifugal partition chromatography (FCPC) is a preparative-scale separations methodology based on the principles of counter current chromatography. Separations by FCPC are typically achieved with higher recoveries and with lower solvent use compared to conventional column chromatography. HSCP...

  3. Pulsed Laser Processing of Paper Materials (United States)

    Schechtel, Florian; Reg, Yvonne; Zimmermann, Maik; Stocker, Thomas; Knorr, Fabian; Mann, Vincent; Roth, Stephan; Schmidt, Michael

    At present the trends in paper and packaging industries are the personalization of products and the use of novel high-tech materials. Laser processes as non-contact and flexible techniques seem to be the obvious choice to address those developments. In this paper we present a basic understanding of the occurring mechanisms of laser based engraving of different paper and paperboard materials, using a picosecond laser source at 1064 nm. The influences on the beam-paper-interaction of grammage, the composition of the paper matrix, as well as the paper inherent cellulose fibers were investigated. Here the ablation threshold of commercially available paper was determined and a matrix ablation effect under the 1064 nm radiation observed. These results were characterized and qualified mainly by means of laser scanning microscope (LSM) micrographs in combination with color-space analytics.

  4. Hygroscopic behaviour of paper and books

    DEFF Research Database (Denmark)

    Derluyn, Hannelore; Janssen, Hans; Diepens, Jan


    This study presents experimental analysis and numerical modeling of hygroscopic moisture buffering by paper and books. First, a literature review of moisture transport properties of paper is presented. Experimental work on two paper types includes SEM analysis of the paper structure, determination...... and not on the relative humidity. Books consist of several paper sheets with air layers between the sheets. To take the air layers into account, a parallel transport model is proposed to determine the effective moisture transport properties of books taking into account the air layers. The dynamic hygroscopic behavior...... of small book samples was measured. It is shown that, although the water vapor permeability of different paper types can be quite different, the effusivity of a book highly depends on the presence of the air layers and can therefore remain comparable for different paper types....

  5. Processing and Structure of Carbon Nanofiber Paper

    Directory of Open Access Journals (Sweden)

    Zhongfu Zhao


    Full Text Available A unique concept of making nanocomposites from carbon nanofiber paper was explored in this study. The essential element of this method was to design and manufacture carbon nanofiber paper with well-controlled and optimized network structure of carbon nanofibers. In this study, carbon nanofiber paper was prepared under various processing conditions, including different types of carbon nanofibers, solvents, dispersants, and acid treatment. The morphologies of carbon nanofibers within the nanofiber paper were characterized with scanning electron microscopy (SEM. In addition, the bulk densities of carbon nanofiber papers were measured. It was found that the densities and network structures of carbon nanofiber paper correlated to the dispersion quality of carbon nanofibers within the paper, which was significantly affected by papermaking process conditions.

  6. Using ion exchange chromatography to purify a recombinantly expressed protein. (United States)

    Duong-Ly, Krisna C; Gabelli, Sandra B


    Ion exchange chromatography (IEX) separates molecules by their surface charge, a property that can vary vastly between different proteins. There are two types of IEX, cation exhange and anion exchange chromatography. The protocol that follows was designed by the authors for anion exchange chromatography of a recombinantly expressed protein having a pI of 4.9 and containing two cysteine residues and one tryptophan residue, using an FPLC system. Prior to anion exchange, the protein had been salted out using ammonium sulfate precipitation and partially purified via hydrophobic interaction chromatography (see Salting out of proteins using ammonium sulfate precipitation and Use and Application of Hydrophobic Interaction Chromatography for Protein Purification). Slight modifications to this protocol may be made to accommodate both the protein of interest and the availability of equipment.

  7. Chitosan-based membrane chromatography for protein adsorption and separation. (United States)

    Liu, Yezhuo; Feng, Zhicheng; Shao, Zhengzhong; Chen, Xin


    A chitosan-based membrane chromatography was set up by using natural chitosan/carboxymethylchitosan (CS/CMCS) blend membrane as the matrix. The dynamic adsorption property for protein (lysozyme as model protein) was detailed discussed with the change in pore size of the membrane, the flow rate and the initial concentration of the feed solution, and the layer of membrane in membrane stack. The best dynamic adsorption capacity of lysozyme on the CS/CMCS membrane chromatography was found to be 15.3mg/mL under the optimal flow conditions. Moreover, the CS/CMCS membrane chromatography exhibited good repeatability and reusability with the desorption efficiency of ~90%. As an application, lysozyme and ovalbumin were successfully separated from their binary mixture through the CS/CMCS membrane chromatography. This implies that such a natural chitosan-based membrane chromatography may have great potential on the bioseparation field in the future.

  8. Applications of resistive heating in gas chromatography: a review. (United States)

    Jacobs, Matthew R; Hilder, Emily F; Shellie, Robert A


    Gas chromatography is widely applied to separate, identify, and quantify components of samples in a timely manner. Increasing demand for analytical throughput, instrument portability, environmental sustainability, and more economical analysis necessitates the development of new gas chromatography instrumentation. The applications of resistive column heating technologies have been espoused for nearly thirty years and resistively heated gas chromatography has been commercially available for the last ten years. Despite this lengthy period of existence, resistively heated gas chromatography has not been universally adopted. This low rate of adoption may be partially ascribed to the saturation of the market with older convection oven technology, coupled with other analytical challenges such as sampling, injection, detection and data processing occupying research. This article assesses the advantages and applications of resistive heating in gas chromatography and discusses practical considerations associated with adoption of this technology.

  9. Phytochemical analysis of ethanolic extract of Dichrostachys Cinerea W and Arn leaves by a thin layer chromatography, high performance thin layer chromatography and column chromatography


    Vijayalakshmi, M; K Periyanayagam; Kavitha, K; K Akilandeshwari


    Background: The leaves of Dichrostachys cinerea are used as laxative, diuretic, painkiller. It is also used in the treatment of gonorrhoea, boils, oedema, gout, veneral diseases and nasopharyngeal affections, etc. Materials and Methods: The Phytochemical investigation of ethanolic extract of D. cinerea leaves were performed by standard chemical tests, thin layer chromatography (TLC) by using various solvent systems, and by high performance liquid chromatography (HPTLC). Two compounds were...

  10. A Review on Ultra Performance Liquid Chromatography

    Directory of Open Access Journals (Sweden)

    Darasanapalli Meenakshi


    Full Text Available UPLC is a rising chromatographic separation technique whose packing materials have smaller particle size lesser than 2.5μm which improves the speed, resolution and sensitivity of analysis. When many scientists experienced separation barriers with conventional HPLC, UPLC extended and expanded the utility of chromatography. The main advantage is a reduction of analysis time which also reduces solvent consumption. The analysis time, solvent consumption and analysis cost are very important factor in many analytical laboratories. The time spent for optimizing new methods can also be greatly reduced. This results in many analysis in a day and quick results which is of very importance to the industries and research laboratories. UPLC principle is same as that of HPLC that is based on Van Deemter equation but decrease in particle size has increased efficiency at increased flow rates.

  11. Biomolecule immobilization techniques for bioactive paper fabrication. (United States)

    Kong, Fanzhi; Hu, Yim Fun


    Research into paper-based sensors or functional materials that can perform analytical functions with active recognition capabilities is rapidly expanding, and significant research effort has been made into the design and fabrication of bioactive paper at the biosensor level to detect potential health hazards. A key step in the fabrication of bioactive paper is the design of the experimental and operational procedures for the immobilization of biomolecules such as antibodies, enzymes, phages, cells, proteins, synthetic polymers and DNA aptamers on a suitably prepared paper membrane. The immobilization methods are concisely categorized into physical absorption, bioactive ink entrapment, bioaffinity attachment and covalent chemical bonding immobilization. Each method has individual immobilization characteristics. Although every biomolecule-paper combination has to be optimized before use, the bioactive ink entrapment method is the most commonly used approach owing to its general applicability and biocompatibility. Currently, there are four common applications of bioactive paper: (1) paper-based bioassay or paper-based analytical devices for sample conditioning; (2) counterfeiting and countertempering in the packaging and construction industries; (3) pathogen detection for food and water quality monitoring; and (4) deactivation of pathogenic bacteria using antimicrobial paper. This article reviews and compares the different biomolecule immobilization techniques and discusses current trends. Current, emerging and future applications of bioactive paper are also discussed.

  12. A novel amide stationary phase for hydrophilic interaction liquid chromatography and ion chromatography. (United States)

    Shen, Guobin; Zhang, Feifang; Yang, Bingcheng; Chu, Changhu; Liang, Xinmiao


    A novel amide stationary phase (ASP) for hydrophilic interaction liquid chromatography (HILIC) has been prepared via the Click chemistry method. It was based on the strategy that the amino group of Asparagine was easily transferred to the corresponding azido group and then clicked onto terminal alkyne-silica gel in the presence of Cu(I)-based catalyst. For the tested polar compounds including nucleosides and nucleic acid bases, ASP-based column has demonstrated good performance in terms of separation efficiency and column stability, and the retention mechanism was found to match well the typical HILIC retention. In addition, the ASP described here showed much better selectivity in separation of inorganic anions under ion chromatography mode relative to other kinds of commercial ASP.

  13. RSC Chromatography Monographs Quantitative In Silico Chromatography Computational Modelling of Molecular Interactions. (United States)

    Hanai, Toshihiko


    All early chromatographic techniques, starting from the primitive "ancient" chromatography introduced by Tswett in the very early twentieth century, perfected in partition chromatography in the 1940s by Martin and Synge, and extended to a variety of additional separation mechanisms later, were first entirely experimental trial-and-error methods. The early years can also be characterized by searching for theoretical base of various separation techniques that would allow establishing relation between the structure of the analytes and their chromatographic behavior. The advent of computers followed by development of the new software then revolutionized the theoretical approaches and enabled detailed modeling instead of tedious experimentation. This book introduces the readers to the era of computational modeling in which molecular interactions are used to analyze the mechanisms of general molecular interactions with a special focus on biological applications. This article is protected by copyright. All rights reserved.

  14. Multifraction separation in countercurrent chromatography (MCSGP). (United States)

    Krättli, Martin; Müller-Späth, Thomas; Morbidelli, Massimo


    The multicolumn countercurrent solvent gradient purification (MCSGP) process is a continuous countercurrent multicolumn chromatography process capable of performing three fraction separations while applying a linear gradient of some modifier. This process can then be used either for the purification of a single species from a multicomponent mixture or to separate a three component mixture in one single operation. In this work, this process is extended to the separation of multifractions, in principle with no limitation. To achieve this goal the MCSGP standard process is extended by introducing one extra separation section per extra fraction to be isolated. Such an extra separation section is realized in this work through a single additional column, so that a n fraction MCSGP process can be realized using a minimum of n columns. Two separation processes were considered to experimentally demonstrate the possibility of realizing a four-fraction MCSGP unit able to purify two intermediate products in a given multicomponent mixture. The first one was a model mixture containing four different proteins. The two proteins eluting in the center of the chromatogram were purified with yields equal to 95% for the early eluting and 92% for the later eluting one. The corresponding purities were 94% and 97%, respectively. Such performance was well superior to that of the batch operation with the same modifier gradient which for the same purity values could not achieve yields larger than 67% and 81%, respectively. Similar performance improvements were found for the second separation where two out of seven charge variants which constitute the mAb Cetuximab currently available on the market have been purified in one single operation using a four-fraction MCSGP unit. In this case, yields of 81% and 65% were obtained with purities of 90% and 89%, respectively. These data compare well with the corresponding data from batch chromatography where with the same gradient and for the same

  15. Simultaneous analysis for water- and fat-soluble vitamins by a novel single chromatography technique unifying supercritical fluid chromatography and liquid chromatography. (United States)

    Taguchi, Kaori; Fukusaki, Eiichiro; Bamba, Takeshi


    Chromatography techniques usually use a single state in the mobile phase, such as liquid, gas, or supercritical fluid. Chromatographers manage one of these techniques for their purpose but are sometimes required to use multiple methods, or even worse, multiple techniques when the target compounds have a wide range of chemical properties. To overcome this challenge, we developed a single method covering a diverse compound range by means of a "unified" chromatography which completely bridges supercritical fluid chromatography and liquid chromatography. In our method, the phase state was continuously changed in the following order; supercritical, subcritical and liquid. Moreover, the gradient of the mobile phase starting at almost 100% CO2 was replaced with 100% methanol at the end completely. As a result, this approach achieved further extension of the polarity range of the mobile phase in a single run, and successfully enabled the simultaneous analysis of fat- and water-soluble vitamins with a wide logP range of -2.11 to 10.12. Furthermore, the 17 vitamins were exceptionally separated in 4min. Our results indicated that the use of dense CO2 and the replacement of CO2 by methanol are practical approaches in unified chromatography covering diverse compounds. Additionally, this is a first report to apply the novel approach to unified chromatography, and can open another door for diverse compound analysis in a single chromatographic technique with single injection, single column and single system.

  16. Studies on Chromatography Fingerprint of Hongqi by High-performance Liquid Chromatography

    Institute of Scientific and Technical Information of China (English)

    Shi Lan FENG; Fang Di HU; Jian Xiong ZHAO; Jing Wen XU; Li Ren CHEN


    Chromatography fingerprint (CFP) of 10 samples of hongqi were studied. 23 common peaks were analyzed, their average similarity was 97.29%. CFP were positioned with main index composition such as formononetin, calycosin and then the contents of index composition were determined. The character and exclusive of CFP of 10 samples of hongqi were clear. CFP and content determination of index composition of hongqi could be used to evaluate the quality of hongqi comprehensively.

  17. Thermal stability of bioactive enzymatic papers. (United States)

    Khan, Mohidus Samad; Li, Xu; Shen, Wei; Garnier, Gil


    The thermal stability of two enzymes adsorbed on paper, alkaline phosphatase (ALP) and horseradish peroxidase (HRP), was measured using a colorimetric technique quantifying the intensity of the product complex. The enzymes adsorbed on paper retained their functionality and selectivity. Adsorption on paper increased the enzyme thermal stability by 2-3 orders of magnitude compared to the same enzyme in solution. ALP and HRP enzymatic papers had half-lives of 533 h and 239 h at 23 degrees C, respectively. The thermal degradation of adsorbed enzyme was found to follow two sequential first-order reactions, indication of a reaction system. A complex pattern of enzyme was printed on paper using a thermal inkjet printer. Paper and inkjet printing are ideal material and process to manufacture low-cost-high volume bioactive surfaces.

  18. Extraction of cocoa proanthocyanidins and their fractionation by sequential centrifugal partition chromatography and gel permeation chromatography. (United States)

    Pedan, Vasilisa; Fischer, Norbert; Rohn, Sascha


    Cocoa beans contain secondary metabolites ranging from simple alkaloids to complex polyphenols with most of them believed to possess significant health benefits. The increasing interest in these health effects has prompted the need to develop techniques for their extraction, fractionation, separation, and analysis. This work provides an update on analytical procedures with a focus on establishing a gentle extraction technique. Cocoa beans were finely ground to an average particle size of centrifugal partition chromatography (SCPC) and gel permeation column chromatography using Sephadex LH-20. For SCPC, a two-phase solvent system consisting of ethyl acetate/n-butanol/water (4:1:5, v/v/v) was successfully applied for the separation of theobromine, caffeine, and representatives of the two main phenolic compound classes flavan-3-ols and flavonols. Gel permeation chromatography on Sephadex LH-20 using a stepwise elution sequence with aqueous acetone has been shown for effectively separating individual flavan-3-ols. Separation was obtained for (-)-epicatechin, proanthocyanidin dimer B2, trimer C1, and tetramer cinnamtannin A2. The purity of alkaloids and phenolic compounds was determined by HPLC analysis and their chemical identity was confirmed by mass spectrometry.

  19. Semantically Detecting Plagiarism for Research Papers


    Reena Kharat, Preeti M. Chavan, Vaibhav Jadhav, Kuldeep Rakibe


    Plagiarism means copying of published work without proper acknowledgement of source. Plagiarism is a major concern, in an academic environment, which affects both the credibility of institutions as well as its ability to ensure quality of its student. Plagiarism detection of research papers deals with checking similarities with other research papers. Manual methods cannot be used for checking research papers, as the assigned reviewer may have inadequate knowledge in the research disciplines. ...

  20. Suggestions for writing high quality scientific papers

    Institute of Scientific and Technical Information of China (English)

    Marc Fisher


    @@ Writing a good scientific paper that will be accepted by a high quality journal requires careful planning and preparation.The process actually begins with the design and performance of the study to be reported upon in the paper.The main sections of the paper which include the introduction,methods,results and discussion are actually components of the planning and execution of the study to be reported.

  1. Personalized Academic Research Paper Recommendation System


    Lee, Joonseok; Lee, Kisung; Kim, Jennifer G.


    A huge number of academic papers are coming out from a lot of conferences and journals these days. In these circumstances, most researchers rely on key-based search or browsing through proceedings of top conferences and journals to find their related work. To ease this difficulty, we propose a Personalized Academic Research Paper Recommendation System, which recommends related articles, for each researcher, that may be interesting to her/him. In this paper, we first introduce our web crawler ...

  2. On a Paper of S S Pillai

    Indian Academy of Sciences (India)

    M Ram Murty; R Thangadurai


    In 1935, Erdös proved that all natural numbers can be written as a sum of a square of a prime and a square-free number. In 1939, Pillai derived an asymptotic formula for the number of such representations. The mathematical review of Pillai’s paper stated that the proof of the above result contained inaccuracies, thus casting a doubt on the correctness of the paper. In this paper, we re-examine Pillai’s paper and show that his argument was essentially correct. Afterwards, we improve the error term in Pillai’s theorem using the Bombieri–Vinogradov theorem.

  3. Sustainable Paper Consumption: Exploring Behavioral Factors

    Directory of Open Access Journals (Sweden)

    Bertha Maya Sopha


    Full Text Available Although the paperless office (PLO management system has been established with the goal of paper usage reduction, demand for paper has still showed an uptrend over the years. Given the substantial pressure on forest ecosystems due to a continued increase of paper consumption, understanding the behavioral aspects of paper consumption is, therefore, required. This present paper aims at exploring the factors underlying paper consumption behavior. Empirical data was acquired through a survey of 266 Indonesian students, involving both undergraduate and postgraduate students. A theoretical model, based on the Comprehensive Action Determination Model (CADM, was tested against the empirical data. It was found that the model received reasonable support from the data. Results indicate that reducing paper consumption behavior is strongly influenced by habit and, marginally significant, by intention. Furthermore, habit formation is influenced by both normative processes and situational influences. The results, to some extent, explain the PLO paradox in a way that the PLO program should have focused on breaking the habit of paper usage instead of promoting the benefits of PLO. Introducing a paper quota and rationing (fee to new students, as the main target, is a potential policy intervention implied from the results.

  4. Recent Advances in Paper-Based Sensors

    Directory of Open Access Journals (Sweden)

    Edith Chow


    Full Text Available Paper-based sensors are a new alternative technology for fabricating simple, low-cost, portable and disposable analytical devices for many application areas including clinical diagnosis, food quality control and environmental monitoring. The unique properties of paper which allow passive liquid transport and compatibility with chemicals/biochemicals are the main advantages of using paper as a sensing platform. Depending on the main goal to be achieved in paper-based sensors, the fabrication methods and the analysis techniques can be tuned to fulfill the needs of the end-user. Current paper-based sensors are focused on microfluidic delivery of solution to the detection site whereas more advanced designs involve complex 3-D geometries based on the same microfluidic principles. Although paper-based sensors are very promising, they still suffer from certain limitations such as accuracy and sensitivity. However, it is anticipated that in the future, with advances in fabrication and analytical techniques, that there will be more new and innovative developments in paper-based sensors. These sensors could better meet the current objectives of a viable low-cost and portable device in addition to offering high sensitivity and selectivity, and multiple analyte discrimination. This paper is a review of recent advances in paper-based sensors and covers the following topics: existing fabrication techniques, analytical methods and application areas. Finally, the present challenges and future outlooks are discussed.

  5. Solution processed aluminum paper for flexible electronics. (United States)

    Lee, Hye Moon; Lee, Ha Beom; Jung, Dae Soo; Yun, Jung-Yeul; Ko, Seung Hwan; Park, Seung Bin


    As an alternative to vacuum deposition, preparation of highly conductive papers with aluminum (Al) features is successfully achieved by the solution process consisting of Al precursor ink (AlH(3){O(C(4)H(9))(2)}) and low temperature stamping process performed at 110 °C without any serious hydroxylation and oxidation problems. Al features formed on several kinds of paper substrates (calendar, magazine, and inkjet printing paper substrates) are less than ~60 nm thick, and their electrical conductivities were found to be as good as thermally evaporated Al film or even better (≤2 Ω/□). Strong adhesion of Al features to paper substrates and their excellent flexibility are also experimentally confirmed by TEM observation and mechanical tests, such as tape and bending tests. The solution processed Al features on paper substrates show different electrical and mechanical performance depending on the paper type, and inkjet printing paper is found to be the best substrate with high and stable electrical and mechanical properties. The Al conductive papers produced by the solution process may be applicable in disposal paper electronics.

  6. Establishment and application of milk fingerprint by gel filtration chromatography. (United States)

    Gao, P; Li, J; Li, Z; Hao, J; Zan, L


    Raw milk adulteration frequently occurs in undeveloped countries. It not only reduces the nutritional value of milk, but it is also harmful to consumers. In this paper, we focused on investigating an efficient method for the quality control of raw milk protein. A gel filtration chromatography (GFC) fingerprint method combined with chemometrics was developed for fingerprint analysis of raw milk. To optimize the GFC conditions, milk fat was removed by centrifugation, and GFC analysis was performed on a Superdex 75 10/300GL column (Just Scientific, Shanghai, China) with 0.2 M NaH2PO4-Na2HPO4 buffer (pH 7.0) as the mobile phase. The flow rate was 0.5mL/min, and the detection wavelength was set at 280 nm. Ten batches of 120 raw milk samples were analyzed to establish the GFC fingerprint under optimal conditions. Six major peaks common to the chromatogram of each raw milk sample were selected for fingerprint analysis, and the characteristic peaks were used to establish a standard chromatographic fingerprint. Principal component analysis was then applied to classify GFC information of adulterated milk and raw milk, allowing adulterated samples to be effectively screened out from the raw milk in principal component analysis scores plot. The fingerprint method demonstrates promising features in detecting milk protein adulteration.

  7. Chromatographic analysis of olopatadine in hydrophilic interaction liquid chromatography. (United States)

    Maksić, Jelena; Jovanović, Marko; Rakić, Tijana; Popović, Igor; Ivanović, Darko; Jančić-Stojanović, Biljana


    In this paper, chromatographic analysis of active substance olopatadine hydrochloride, which is used in eye drops as antihistaminic agent, and its impurity E isomer by hydrophilic interaction liquid chromatography (HILIC) and application of design of experiments (DoE) methodology are presented. In addition, benzalkonium chloride is very often used as a preservative in eye drops. Therefore, the evaluation of its chromatographic behavior in HILIC was carried out as well. In order to estimate chromatographic behavior and set optimal chromatographic conditions, DoE methodology was applied. After the selection of important chromatographic factors, Box-Behnken design was utilized, and on the basis of the obtained models factor effects were examined. Then, multi-objective robust optimization is performed aiming to obtain chromatographic conditions that comply with several quality criteria simultaneously: adequate and robust separation of critical peak pair and maximum retention of the first eluting peak. The optimal conditions are identified by using grid point search methodology. The experimental verification confirmed the adequacy of the defined optimal conditions. Finally, under optimal chromatographic conditions, the method was validated and applicability of the proposed method was confirmed.

  8. SAM Gcms Chromatography Performed at Mars : Elements of Interpretation (United States)

    Szopa, C.; Coll, P. J.; Buch, A.; François, P.; Cabane, M.; Coscia, D.; Teinturier, S.; Navarro-Gonzalez, R.; Glavin, D. P.; Freissinet, C.; Mahaffy, P. R.


    The characterisation of the chemical and mineralogical composition of regolith samples collected with the Curiosity rover is a primary objective of the SAM experiment. These data should provide essential clues on the past habitability of Gale crater. Interpretation of the data collected after SAM pyrolysis evolved gas analysis (EGA) and gas chromatography mass spectrometry (GC-MS) experiments on the first soil samples collected by MSL at the Rocknest Aeolian Deposit in Gale Crater has been challenging due to the concomitant presence in the ovens of an oxychlorine phase present in the samples, and a derivatization agent coming from the SAM wet chemistry experiment (Glavin et al., 2013). Moreover, accurate identification and quantification, in the SAM EGA mode, of volatiles released from the heated sample, or generated by reactions occurring in the SAM pyrolysis oven, is also difficult for a few compounds due to evolution over similar temperature ranges and overlap of their MS signatures. Hence, the GC analyses, coupled with MS, enabled the separation and identification and quantification of most of the volatile compounds detected. These results can have been obtained through tests and calibration done with GC individual spare components and with the SAM testbed. This paper will present a view of the interpretation of the chromatograms obtained when analyzing the Rocknest and John Klein solid samples delivered to SAM, on sols 96 and 199 respectively, supported by laboratory calibrations.

  9. Determination of inorganic anions in papermaking waters by ion chromatography

    Directory of Open Access Journals (Sweden)



    Full Text Available A suppressed ion chromatography (IC method for the determination of inorganic anions in process water from paperboard production was developed and validated. Common inorganic anions (Cl-, NO3-, PO43- and SO42- were detected in fresh and process water samples collected from a paperboard production system at 16 characteristic points. It was shown that the use of an IonPac®-AS14 column under isocratic conditions with Na2CO3/NaHCO3 as the eluent and a suppression device proved to be a reliable analytical solution for the separation of the inorganic anions present in papermaking waters. This IC method is quite satisfactory concerning selectivity and sensitivity, and enables the determination of several inorganic anions over a wide concentration range. According to the obtained results, the total amount of analyzed inorganic anions was below 0.1 g/L, i.e., below the critical value which may trigger operational problems in paper production.

  10. Papers, Volume 2 1986-1989

    DEFF Research Database (Denmark)

    Thoft-Christensen, Palle

    In this Volume 2 of “Papers”, 20 papers published in 1986 - 1989 are presented. The papers are reproduced by using scanning techniques and retyping of equations. During this work, small modifications and corrections have been made. Unfortunately, new errors may have been introduced. This is my...

  11. Light Sterile Neutrinos: A White Paper

    DEFF Research Database (Denmark)

    Abazajian, K. N.; Acero, M. A.; Agarwalla, S. K.;


    This white paper addresses the hypothesis of light sterile neutrinos based on recent anomalies observed in neutrino experiments and the latest astrophysical data.......This white paper addresses the hypothesis of light sterile neutrinos based on recent anomalies observed in neutrino experiments and the latest astrophysical data....

  12. Review Papers are Important and Worth Writing (United States)

    Reviews are papers that compile, summarize, critique and synthesize the available information on a topic. They are highly represented in Environmental Toxicology and Chemistry’s 100 most cited papers for a good and obvious reason. If you wish to provide citation to support your ...

  13. Papers, Volume 1 1962-1985

    DEFF Research Database (Denmark)

    Thoft-Christensen, Palle

    In this Volume 1 of “Papers”, 20 papers published from 1962 to 1985 are presented. The papers are reproduced by using scanning techniques and retyping of equations. During this work, small modifications and corrections have been made. Unfortunately, new errors may have been introduced. This is my...

  14. MITA Working Papers in Psycholinguistics, Volume 2. (United States)

    Otsu, Yukio, Ed.

    Seven original research papers are presented. The titles and authors are as follows: "Acquisition of the Argument-Structure of Verbs" (Mika Endo); "A Note on Semantic Selection" (Yoshio Endo); "The Governing Category Parameter in Second Language" (Makiko Hirakawa); "The Use of Connectives in English Academic Papers Written by Japanese Students"…

  15. College Goal: Internationalizing the Curriculum. White Paper. (United States)

    Eith, Gary; Fye, Chuck

    This paper asserts that internationalizing or globalizing the community college curriculum will be necessary to meet the emerging needs of an increasingly diverse U.S. workforce and employer demand for international communication skills. The paper discusses globalization, establishes a common base of understanding of where Lakeland Community…

  16. The Wage Gap: Briefing Paper #1. (United States)

    National Committee on Pay Equity, Washington, DC.

    Women have made slow, steady progress in the labor market since 1979, but the wage gap has not narrowed significantly. This briefing paper updates a September 1987 paper based on "Male-Female Differences in Work Experience, Occupations, and Earnings: 1984" (Current Population Reports, Household Economic Studies, Series P-70, No. 10, issued in…

  17. Accountability: Papers from master theses 2008

    NARCIS (Netherlands)

    C.D. Knoops (Chris); J. Noeverman (Jan)


    textabstractWe are proud to be able to present this book, the first volume of what we intend to become an annual book series. This year’s edition contains eleven papers. Each paper is based on a thesis in the field of Accounting, Auditing and Control, on which these students received a Master’s degr

  18. Uniting the paper and digital worlds. (United States)

    Schreiner, Keri


    Digital pen and paper technologies are increasingly popular in vertical markets such as health care, but the broad market of everyday consumers remains untapped. In the past year, several developers targeting that market have focused on notetakers-whether journalists, lawyers, or students-in the hope of uniting the paper and digital worlds.

  19. Abstracts of papers in this issue

    Institute of Scientific and Technical Information of China (English)


    This paper presents a comprehensive review of the functional approach and cognitive approach to the nature of language and its relation to other aspects of human cognition. The paper starts with a brief discussion of the origins and the core tenets of the two approaches in Section 1.

  20. Paper Document Storage: A Summary of Options. (United States)

    Dixon, Ross


    Discusses problems with paper storage; considers organizational requirements for storage, including access, cost, and security; describes storage options, including filing cabinets, open shelving, cabinets, carousels, mobile racking, and rotary storage; and examines paper storage as part of a records management strategy. (LRW)

  1. Semantically Detecting Plagiarism for Research Papers

    Directory of Open Access Journals (Sweden)

    Reena Kharat, Preeti M. Chavan, Vaibhav Jadhav, Kuldeep Rakibe


    Full Text Available Plagiarism means copying of published work without proper acknowledgement of source. Plagiarism is a major concern, in an academic environment, which affects both the credibility of institutions as well as its ability to ensure quality of its student. Plagiarism detection of research papers deals with checking similarities with other research papers. Manual methods cannot be used for checking research papers, as the assigned reviewer may have inadequate knowledge in the research disciplines. They may have different subjective views, causing possible misinterpretations. Therefore, there was an urgent need for an effective and feasible approach to check the submitted research papers with support of automated software. A method like- text mining method came into picture to solve the problem of automatically checking the research papers semantically. Our proposed system uses Term Frequency- Inverse Document Frequency (TFIDF and Latent Semantic Indexing (LSI to semantically find plagiarism.

  2. Choosing to write the paper format thesis. (United States)

    Morris, H M; Tipples, G


    Graduate students today may be faced with the option of writing either a traditional format thesis or a paper format thesis. In contrast to the traditional format in which the text body consists of four or five chapters, the body of the paper format thesis can be comprised of an introductory chapter, two or more papers written as publishable manuscripts, and a conclusion. In this article, an overview of the paper format thesis is presented and contrasted with the traditional format thesis. The description of the paper format thesis is followed by its advantages and disadvantages for writers and readers. It is by weighing all possible pros and cons, as well as considering one's individual situation, that the graduate student will be able to decide which format of thesis to write.

  3. Comparison of high-performance liquid chromatography and supercritical fluid chromatography using evaporative light scattering detection for the determination of plasticizers in medical devices. (United States)

    Lecoeur, Marie; Decaudin, Bertrand; Guillotin, Yoann; Sautou, Valérie; Vaccher, Claude


    Recently, interest in supercritical fluid chromatography (SFC) has increased due to its high throughput and the development of new system improving chromatographic performances. However, most papers dealt with fundamental studies and chiral applications and only few works described validation process of SFC method. Likewise, evaporative light scattering detection (ELSD) has been widely employed in liquid chromatography but only a few recent works presented its quantitative performances hyphenated with SFC apparatus. The present paper discusses about the quantitative performances of SFC-ELSD compared to HPLC-ELSD, for the determination of plasticizers (ATBC, DEHA, DEHT and TOTM) in PVC tubing used as medical devices. After the development of HPLC-ELSD, both methods were evaluated based on the total error approach using accuracy profile. The results show that HPLC-ELSD was more precise than SFC-ELSD but lower limits of quantitation were obtained by SFC. Hence, HPLC was validated in the ± 10% acceptance limits whereas SFC lacks of accuracy to quantify plasticizers. Finally, both methods were used to determine the composition of plasticized-PVC medical devices. Results demonstrated that SFC and HPLC both hyphenated with ELSD provided similar results.

  4. Quantitative analysis of multiple components based on liquid chromatography with mass spectrometry in full scan mode. (United States)

    Xu, Min Li; Li, Bao Qiong; Wang, Xue; Chen, Jing; Zhai, Hong Lin


    Although liquid chromatography with mass spectrometry in full scan mode can obtain all the signals simultaneously in a large range and low cost, it is rarely used in quantitative analysis due to several problems such as chromatographic drifts and peak overlap. In this paper, we propose a Tchebichef moment method for the simultaneous quantitative analysis of three active compounds in Qingrejiedu oral liquid based on three-dimensional spectra in full scan mode of liquid chromatography with mass spectrometry. After the Tchebichef moments were calculated directly from the spectra, the quantitative linear models for three active compounds were established by stepwise regression. All the correlation coefficients were more than 0.9978. The limits of detection and limits of quantitation were less than 0.11 and 0.49 μg/mL, respectively. The intra- and interday precisions were less than 6.54 and 9.47%, while the recovery ranged from 102.56 to 112.15%. Owing to the advantages of multi-resolution and inherent invariance properties, Tchebichef moments could provide favorable results even in the situation of peaks shifting and overlapping, unknown interferences and noise signals, so it could be applied to the analysis of three-dimensional spectra in full scan mode of liquid chromatography with mass spectrometry.

  5. Development of paper-based microfluidic analytical device for iron assay using photomask printed with 3D printer for fabrication of hydrophilic and hydrophobic zones on paper by photolithography. (United States)

    Asano, Hitoshi; Shiraishi, Yukihide


    This paper describes a paper-based microfluidic analytical device for iron assay using a photomask printed with a 3D printer for fabrication of hydrophilic and hydrophobic zones on the paper by photolithography. Several designed photomasks for patterning paper-based microfluidic analytical devices can be printed with a 3D printer easily, rapidly and inexpensively. A chromatography paper was impregnated with the octadecyltrichlorosilane n-hexane solution and hydrophobized. After the hydrophobic zone of the paper was exposed to the UV light through the photomask, the hydrophilic zone was generated. The smallest functional hydrophilic channel and hydrophobic barrier were ca. 500 μm and ca. 100 μm in width, respectively. The fabrication method has high stability, resolution and precision for hydrophilic channel and hydrophobic barrier. This test paper was applied to the analysis of iron in water samples using a colorimetry with phenanthroline.

  6. Purification of anthocyanins from species of Banksia and Acacia using high-voltage paper electrophoresis. (United States)

    Asenstorfer, Robert E; Morgan, Anne L; Hayasaka, Yoji; Sedgley, Margaret; Jones, Graham P


    A new method has been developed for the isolation and rapid identification of anthocyanins from two floricultural crops based on the use of high-voltage paper electrophoresis with bisulphite buffer. Using this method, anthocyanin pigments were successfully purified as their negatively charged bisulphite-addition compounds from crude extracts of plant tissue. In conjunction with liquid chromatography-electrospray mass spectrometry, the method enabled the anthocyanins from the flowers of two Banksia species and the leaves of two Acacia species to be identified. The Banksia flowers contained both cyanidin and peonidin-based pigments, while the Acacia leaves contained cyanidin and delphinidin derivatives.

  7. Polyfluorinated surfactants (PFS) in paper and board coatings for food packaging

    DEFF Research Database (Denmark)

    Trier, Xenia; Granby, Kit; Christensen, Jan H


    range of polyfluorinated surfactants (PFS) used for food contact materials, primarily to impart oil and water repellency on paper and board. PFS are of interest, as they can be precursors of poly- and perfluorinated alkyl substances (PFAS), of which several are persistent and are found worldwide...... in human blood and in the environment. Materials and methods To determine the elemental composition of PFS, we combined information from patents, chemical suppliers and analyses of industrial blends using ultra performance liquid chromatography-negative electrospray ionisation quadrupole time...

  8. Paper in the Era of Digitisation

    Directory of Open Access Journals (Sweden)

    Klemen Možina


    Full Text Available EXTENDED ABSTRACT:The paper has always been and it remains to be the primary information carrier though only 0.1 % of the total information is recorded on this media. The paper production industry has a great impact on the environment which is mostly due to the use of raw materials (wood of conifers and deciduous trees, fillers (CaCO 3, additional materials (dyes, glue, binders, retentionaids, and chemicals (acids and bases. However, the greatest impact on the environmentis caused by the extensive water consumption. To produce 1 ton of paper up to 60 m3 of freshwater are necessary. The water is not the only resource needed in the production cycle. Besides, the consumption of electrical energy (approximately 10,000 MJ/t pap, waste paper (paper represents 35 % of waste, and air pollution (paper production and transport should be taken into consideration. In spite of the above mentioned environmental threats the paper still remains an important element of the everyday life and the use of modern information technology (personal computers, telefax, Internet has increased its demand and consumption. It is important that the paper is produced from natural materials which are later released into environment without significant environmental consequences. The technology of paper recycling and re-use is widely known and a must of any responsible and professional social environment. Digitisation has increased the consumption of electrical energy as a consequence of production, use and reprocessing of different devices. Unlike a written record, a digital record has no permanent value and the electromagnetic field has a negative effect on the digital records. Digital records have to be constantly updated and adjusted to the computer software and hardware. A book and its content represent a treasure and an invaluable part of the cultural heritage. To use a book it is necessary to learn the alphabet whereas to read digital records we need to be computer and

  9. Lipophilic properties of anti-Alzheimer's agents determined by micellar electrokinetic chromatography and reversed-phase thin-layer chromatography. (United States)

    Godyń, Justyna; Hebda, Michalina; Więckowska, Anna; Więckowski, Krzysztof; Malawska, Barbara; Bajda, Marek


    Lipophilicity as one of the most important physicochemical properties of the biologically active compounds is closely related to their pharmacokinetic parameters and therefore, it is taken into account at the design stage of new drugs. Among the novel, fast and reliable methods for determination of the lipophilicity of compounds micellar electrokinetic chromatography (MEKC) is considered to be an appropriate one for bioactive molecules, as it closely mimics the physiological conditions. In this paper MEKC was used for the estimation of log P values for 49 derivatives of phthalimide, tetrahydroisochinoline and indole, designed and synthesized as potential anti-Alzheimer's agents with cholinesterase inhibitory activity. RP-TLC method was applied for determination of another lipophilicity descriptor - RM0 . The results of both experimental methods were compared with each other giving satisfactory correlation (R = 0.784), and with computational methods (Marvin, ChemOffice Software) resulting in weaker correlation (R = 0.466 - 0.687). The lipophilicity-activity relationship was finally established, showing significant influence of lipophilicity on cholinesterase inhibition in some subgroups of phthalimide derivatives. This article is protected by copyright. All rights reserved.


    Directory of Open Access Journals (Sweden)



    Full Text Available At the end of the paper production process, reducing its moisture content is achieved by passing the finished product in continuous flow through an electric oven. This paper assumes humidity control, which in turn determine the electrical conductivity of the paper. The operating principle of non-contact method is: a transmitting coil Tx supplied with alternating current at an audio frequency is placed on the paper comes out of the oven. A reception coil Rx is located at a short distance, s, away from the Tx coil. The magnetic field varies in time and emission Tx coil induces circular currents of very low intensity in wet paper. These currents generate a secondary magnetic field Hs , which is sensed by the receiver Rx coil together with the magnetic field Hp. The ratio of the secondary magnetic field Hs and Hp primary magnetic field (Hs \\ Hp is directly proportional to the conductivity of the paper. Thus it is possible to build a device to measure the conductivity of paper contactless electromagnetic technique.

  11. MXene-on-Paper Coplanar Microsupercapacitors

    KAUST Repository

    Kurra, Narendra


    A simple and scalable direct laser machining process to fabricate MXene-on-paper coplanar microsupercapacitors is reported. Commercially available printing paper is employed as a platform in order to coat either hydrofluoric acid-etched or clay-like 2D Ti3C2 MXene sheets, followed by laser machining to fabricate thick-film MXene coplanar electrodes over a large area. The size, morphology, and conductivity of the 2D MXene sheets are found to strongly affect the electrochemical performance due to the efficiency of the ion-electron kinetics within the layered MXene sheets. The areal performance metrics of Ti3C2 MXene-on-paper microsupercapacitors show very competitive power-energy densities, comparable to the reported state-of-the-art paper-based microsupercapacitors. Various device architectures are fabricated using the MXene-on-paper electrodes and successfully demonstrated as a micropower source for light emitting diodes. The MXene-on-paper electrodes show promise for flexible on-paper energy storage devices. © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  12. Paper recycling framework, the "Wheel of Fiber". (United States)

    Ervasti, Ilpo; Miranda, Ruben; Kauranen, Ilkka


    At present, there is no reliable method in use that unequivocally describes paper industry material flows and makes it possible to compare geographical regions with each other. A functioning paper industry Material Flow Account (MFA) that uses uniform terminology and standard definitions for terms and structures is necessary. Many of the presently used general level MFAs, which are called frameworks in this article, stress the importance of input and output flows but do not provide a uniform picture of material recycling. Paper industry is an example of a field in which recycling plays a key role. Additionally, terms related to paper industry recycling, such as collection rate, recycling rate, and utilization rate, are not defined uniformly across regions and time. Thus, reliably comparing material recycling activity between geographical regions or calculating any regional summaries is difficult or even impossible. The objective of this study is to give a partial solution to the problem of not having a reliable method in use that unequivocally describes paper industry material flows. This is done by introducing a new material flow framework for paper industry in which the flow and stage structure supports the use of uniform definitions for terms related to paper recycling. This new framework is termed the Detailed Wheel of Fiber.

  13. Possibilities of Laser Processing of Paper Materials (United States)

    Stepanov, Alexander; Saukkonen, Esa; Piili, Heidi

    Nowadays, lasers are applied in many industrial processes: the most developed technologies include such processes as laser welding, hybrid welding, laser cutting of steel, etc. In addition to laser processing of metallic materials, there are also many industrial applications of laser processing of non-metallic materials, like laser welding of polymers, laser marking of glass and laser cutting of wood-based materials. It is commonly known that laser beam is suitable for cutting of paper materials as well as all natural wood-fiber based materials. This study reveals the potential and gives overview of laser application in processing of paper materials. In 1990's laser technology increased its volume in papermaking industry; lasers at paper industry gained acceptance for different perforating and scoring applications. Nowadays, with reduction in the cost of equipment and development of laser technology (especially development of CO2 technology), laser processing of paper material has started to become more widely used and more efficient. However, there exists quite little published research results and reviews about laser processing of paper materials. In addition, forest industry products with pulp and paper products in particular are among major contributors for the Finnish economy with 20% share of total exports in the year 2013. This has been the standpoint of view and motivation for writing this literature review article: when there exists more published research work, knowledge of laser technology can be increased to apply it for processing of paper materials.

  14. Instrumentation for hand-portable liquid chromatography. (United States)

    Sharma, Sonika; Plistil, Alex; Simpson, Robert S; Liu, Kun; Farnsworth, Paul B; Stearns, Stanley D; Lee, Milton L


    Liquid chromatography (LC) has lagged behind gas chromatography (GC) in developments related to hand-portable instrumentation. In this work, a new battery-operated (24V DC) nano-flow pumping system with a stop-flow injector was developed and integrated with an on-column UV-absorption detector (254nm) that was reduced in size to an acceptable weight and power usage for field operation. The pumping system, which includes nano-flow pump, stepper motor and high-pressure valve weighs only 1.372kg (3lbs) and can generate up to 110.32MPa (16,000psi) pressure. A major advantage of this pump is that it does not employ a splitter, since it was specifically designed for capillary column use. The volume capacity of the pump is 24μL, and a sample volume as low as 10nL can be injected. Flow rate calibration (300nL to 6.12μL per min) was performed, and an accuracy >99.94% was obtained. The percent injection carry-over was found to be low (RSD 0.31%), which makes it practical for quantitative analysis. The detector linear range and limit of detection (LOD) were determined using sodium anthraquinone-2-sulfonate. A linear regression coefficient (R) of 0.9996 was obtained for a plot of log peak area versus log concentration over the range of 3.2μM to 6.5mM, and the LOD (S/N=3) was found to be 7.8fmol (0.13μM). The short term noise of the detector is comparable to commercially available detectors (∼10(-5)AU). In this work, the system was tested in the laboratory using regular line power (120V AC) with an AC to DC adapter. Reversed-phase isocratic separations were performed using a 15.5cm×75μm i.d. fused silica capillary column containing a monolithic stationary phase synthesized from 1,6-hexanediol dimethacrylate. Good retention time repeatability (RSD 0.09-0.74%) was obtained for a mixture containing an unretained marker (i.e., uracil) and a homologous series of alkyl benzenes.

  15. Mixed waste paper to ethanol fuel

    Energy Technology Data Exchange (ETDEWEB)


    The objectives of this study were to evaluate the use of mixed waste paper for the production of ethanol fuels and to review the available conversion technologies, and assess developmental status, current and future cost of production and economics, and the market potential. This report is based on the results of literature reviews, telephone conversations, and interviews. Mixed waste paper samples from residential and commercial recycling programs and pulp mill sludge provided by Weyerhauser were analyzed to determine the potential ethanol yields. The markets for ethanol fuel and the economics of converting paper into ethanol were investigated.

  16. Collected software engineering papers, volume 12 (United States)


    This document is a collection of selected technical papers produced by participants in the Software Engineering Laboratory (SEL) from November 1993 through October 1994. The purpose of the document is to make available, in one reference, some results of SEL research that originally appeared in a number of different forums. This is the 12th such volume of technical papers produced by the SEL. Although these papers cover several topics related to software engineering, they do not encompass the entire scope of SEL activities and interests. Additional information about the SEL and its research efforts may be obtained from the sources listed in the bibliography at the end of this document.

  17. Collected software engineering papers, volume 11 (United States)


    This document is a collection of selected technical papers produced by participants in the Software Engineering Laboratory (SEL) from November 1992 through November 1993. The purpose of the document is to make available, in one reference, some results of SEL research that originally appeared in a number of different forums. This is the 11th such volume of technical papers produced by the SEL. Although these papers cover several topics related to software engineering, they do not encompass the entire scope of SEL activities and interests. Additional information about the SEL and its research efforts may be obtained from the sources listed in the bibliography at the end of this document.

  18. Non-Destructive Evaluation of Historical Paper Based on pH Estimation from VOC Emissions

    Directory of Open Access Journals (Sweden)

    Boris Pihlar


    Full Text Available Volatile organic compounds (VOCs emitted from materials during degradationcan be a valuable source of information. In this work, the emissions of furfural and aceticacid from cellulose were studied using solid-phase micro-extraction (SPME incombination with gas chromatography-mass spectrometry. Two sampling techniques wereemployed: static headspace sampling using SPME for 1 h at 40 oC after 18-h samplepreparation at 80 oC in a closed glass vial, and contact SPME in a stack of paper (or abook. While a number of VOCs are emitted from paper under conditions of natural oraccelerated degradation, two compounds were confirmed to be of particular diagnosticvalue: acetic acid and furfural. The emissions of furfural are shown to correlate with pH ofthe cellulosic environment. Since pH is one of the most important parameters regardingdurability of this material, the developed method could be used for non-destructiveevaluation of historical paper.

  19. Rational selection of substrates to improve color intensity and uniformity on microfluidic paper-based analytical devices. (United States)

    Evans, Elizabeth; Gabriel, Ellen Flávia Moreira; Coltro, Wendell Karlos Tomazelli; Garcia, Carlos D


    A systematic investigation was conducted to study the effect of paper type on the analytical performance of a series of microfluidic paper-based analytical devices (μPADs) fabricated using a CO2 laser engraver. Samples included three different grades of Whatman chromatography paper, and three grades of Whatman filter paper. According to the data collected and the characterization performed, different papers offer a wide range of flow rate, thickness, and pore size. After optimizing the channel widths on the μPAD, the focus of this study was directed towards the color intensity and color uniformity formed during a colorimetric enzymatic reaction. According to the results herein described, the type of paper and the volume of reagents dispensed in each detection zone can determine the color intensity and uniformity. Therefore, the objective of this communication is to provide rational guidelines for the selection of paper substrates for the fabrication of μPADs.

  20. Shandong Linqing Yinhe Paper Co., Ltd.

    Institute of Scientific and Technical Information of China (English)

    Wang Gang


    @@ Ms. Huang Xianshu, Canadian Chinese, is the General Manager of the import & export sector, Shandong Linqing Yinhe Paper Co., Ltd.In 2001, she gave up the outstanding job and vealthy life in Canada, returned China.

  1. Paper waste - Recycling, incineration or landfilling?

    DEFF Research Database (Denmark)

    Villanueva, Alejandro; Wenzel, Henrik


    comparisons of different management options for waste paper. Despite claims of inconsistency, the LCAs reviewed illustrate the environmental benefits in recycling over incineration or landfill options, for paper and cardboard waste. This broad consensus was found despite differences in geographic location......A review of existing life cycle assessments (LCAs) on paper and cardboard waste has been undertaken. The objectives of the review were threefold. Firstly, to see whether a consistent message comes out of published LCA literature on optimum disposal or recycling solutions for this waste type....... Such message has implications for current policy formulation on material recycling and disposal in the EU. Secondly, to identify key methodological issues of paper waste management LCAs, and enlighten the influence of such issues on the conclusions of the LCA studies. Thirdly, in light of the analysis made...

  2. Cellulose nanofibers use in coated paper (United States)

    Richmond, Finley

    Cellulose Nanofibers (CNF) are materials that can be obtained by the mechanical breakdown of natural fibers. CNF have the potential to be produced at low cost in a paper mill and may provide novel properties to paper, paper coatings, paints, or other products. However, suspensions have a complex rheology even at low solid contents. To be able to coat, pump, or mix CNF at moderate solids, it is critical to understand the rheology of these suspensions and how they flow in process equipment; current papers only report the rheology up to 6% solids. Few publications are available that describe the coating of CNF onto paper or the use of CNF as an additive into a paper coating. The rheology of CNF suspensions and coatings that contain CNF were characterized with parallel-disk geometry in a controlled stress rheometer. The steady shear viscosity, the complex viscosity, the storage modulus, and the yield stress were determined for the range of solids or concentrations (2.5-10.5%). CNF were coated onto paper with a laboratory rod coater, a size press and a high speed cylindrical laboratory coater (CLC). For each case, the coat weights were measures and the properties of the papers were characterized. CNF water base suspension was found to be a shear thinning with a power law index of around 0.1. Oscillatory tests showed a linear viscoelastic region at low strains and significant storage and loss moduli even at low solids. The Cox Merz rule does not hold for CNF suspensions or coating formulations that contain CNF with complex viscosities that are about 100 times larger than the steady shear viscosities. Paper coating formulations that contain CNF were found to have viscosities and storage and loss moduli that are over ten times larger than coatings that contain starch at similar solids. CNF suspensions were coated on papers with low amount transferred on paper either at high solids or high nip loadings. The amount transferred appears to be controlled by an interaction of

  3. From course assignment paper to publishable manuscript. (United States)

    Rew, Lynn


    Both undergraduate and graduate nursing students are expected to write numerous papers in their educational programs; however, most of these papers are never published. Many students and faculty lack the skills needed to convert a course assignment paper to a publishable manuscript. The purpose of this article is to describe 10 steps that can transform a course assignment paper into a publishable manuscript. These steps include outlining, clarifying the topic, clearly stating the purpose, identifying an appropriate audience, revising with faculty's feedback, querying journal editors, revising to conform to journal's author guidelines, requesting and responding to peer feedback, and finally editing and proofreading prior to submitting the manuscript. Faculty members are encouraged to make writing assignments that students can then convert to publishable manuscripts. Such publications form an essential cornerstone of professional holistic nursing.


    Institute of Scientific and Technical Information of China (English)

    Heng Zhang; Kefu Chen; Rendang Yang


    The flow behavior of paper coating is critical to the coating operation. In this work, the influence of the added agents on the flow behavior and the viscoelastic behavior is investigated using rheometer in steady and dynamic oscillatory modes.


    Institute of Scientific and Technical Information of China (English)

    HengZhang; KefuChen; RendangYang


    The flow behavior of paper coating is critical to thecoating operation. In this work, the influence of theadded agents on the flow behavior and theviscoelastic behavior is investigated using rheometerin steady and dynamic oscillatory modes.

  6. Paper mill wastewater detoxification by solar photocatalysis

    Energy Technology Data Exchange (ETDEWEB)

    Sattler, C.; Funken, K.H.; Oliveira, L. de; Tzschirner, M. [German Aerospace Center, Inst. of Technical Thermodynamics - Solar Research, Cologne (Germany); Machado, A.E.H. [Lab. de Fotoquimica - Inst. de Quimica, Univ. Federal de Uberlandia, Uberlandia, MG (Brazil)


    In the WATER project the German Aerospace Center, DLR, and the Universidade Federal de Uberlandia, UFU, analyse the possibilities of treating paper mill effluents by solar photocatalysis for the paper mill of the Brazilian paper producer Votorantim Celulose e Papel, VCP, at Luiz Antonio, SP, Brazil. The degradation of the bio-polymer lignin is a vast problem in paper production. The tests have shown that treatment by the photocatalyst TiO{sub 2} and solar radiation is an ecological future oriented approach to solve this problem. The treatment of lignin containing process water by solar photocatalysis was optimised and the economics for solar treatment plants of different sizes was estimated to check the possibilities for implementing the technology in industrial processes. (orig.)

  7. Working papers cage Mod 2A definitions

    Energy Technology Data Exchange (ETDEWEB)

    Sprouse, L.D.


    This report presents working papers for the Cage Mod 2A program. Cost data are presented for manpower, irradiation, nuclear fuels and targets, security, transportation, reactor start-up and reactor shutdown.

  8. Effect of calendering on paper surface properties (United States)

    Vernhes, P.; Dubé, M.; Bloch, J.-F.


    Calendering of paper is an industrial finishing process designed to smoothen its surface so as to improve gloss as well as printability. In this article, we describe how calendering affects paper roughness on both microscopic and macroscopic length scales. We also discuss how these modifications relate to the morphology of the fibers composing the paper sheets. The characterization of the surface is carried out using an optical profilometer and two different species of fibers, as well as their mixture, are used. We first show that calendering induces modifications of the surface on all length scales measured and that these modifications are related by straightforward transformations. We also show that these results hold for papers formed from a mixture of fibers.

  9. Origami: Paper Folding--The Algorithmic Way. (United States)

    Heukerott, Pamela Beth


    Describes origami, the oriental art of paper folding as an activity to teach upper elementary students concepts and skills in geometry involving polygons, angles, measurement, symmetry, and congruence. (PK)

  10. Life cycle assessment of waste paper management

    DEFF Research Database (Denmark)

    Merrild, Hanna Kristina; Damgaard, Anders; Christensen, Thomas Højlund


    The significance of technical data, as well as the significance of system boundary choices, when modelling the environmental impact from recycling and incineration of waste paper has been studied by a life cycle assessment focusing oil global warming potentials. The consequence of choosing a spec...... of scientific discussion on how to best address system analysis of recycling, for paper and other recyclable materials.......The significance of technical data, as well as the significance of system boundary choices, when modelling the environmental impact from recycling and incineration of waste paper has been studied by a life cycle assessment focusing oil global warming potentials. The consequence of choosing...... a specific set of data for the reprocessing technology, the virgin paper manufacturing technology and the incineration technology, as well as the importance of the recycling rate Was Studied. Furthermore, the system was expanded to include forestry and to include fossil fuel energy substitution from saved...

  11. Electronic paper rewrites the rulebook for displays (United States)

    Graham-Rowe, Duncan


    Following years of development, electronic paper is now entering ebooks, mobile phones and signs, and, as Duncan Graham-Rowe reports, is starting to gain the market acceptance that it has long strived for.

  12. Briefing paper for universities on Core Maths


    Glaister, Paul


    This briefing paper outlines the rationale for and development of the new Core Maths qualifications, the characteristics of Core Maths, and why Core Maths is important for higher education. It is part of a communication to university vice-chancellors from the Department for Business, Innovation and Skills (BIS) comprising this paper and a joint Ministerial letter from Jo Johnson, Minister of State for Universities and Science in BIS, and Nick Gibb, Minister of State for Schools in the Departm...

  13. NGNP High Temperature Materials White Paper

    Energy Technology Data Exchange (ETDEWEB)

    Lew Lommers; George Honma


    This white paper is one in a series of white papers that address key generic issues of the combined construction and operating license (COL) pre-application program key generic issues for the Next Generation Nuclear Plant reactor using the prismatic block fuel technology. The purpose of the pre-application program interactions with the NRC staff is to reduce the time required for COL application review by identifying and addressing key regulatory issues and, if possible, obtaining agreements for their resolution

  14. Abstracts of papers in this issue

    Institute of Scientific and Technical Information of China (English)


    Cognitive stylistics and its relatitmship to neighboring disciplines (p. 163 ) HU Zhuanglin (English Dept., Peking University, Beijing 100871, China) The paper briefly reviews the new discipline of cognitive stylistics, which developed rapidly in the last decade of the 20^th century, as well as its relevant theoretical constructs. The paper highly appreciates those Chinese scholars who introduced this new discipline into China and their

  15. Paper-based mobile access to databases


    Signer, Beat; Norrie, Moira C.; Grossniklaus, Michael; Belotti, Rudi; Decurtins, Corsin; Weibel, Nadir


    Our demonstration is a paper-based interactive guide for visitors to the world's largest international arts festival that was developed as part of a project investigating new forms of context-aware information delivery and interaction in mobile environments. Information stored in a database is accessed from a set of interactive paper documents, including a printed festival brochure, a city map and a bookmark. Active areas are defined within the documents and selection of these using a special...

  16. Special Issue: Selected papers from ECS'97

    DEFF Research Database (Denmark)


    This Special Issue of Analog Integrated Circuits and Signal Processing presents extended versions of selected papers from the First Electronic Circuits and Systems Conference (ECS'97) which was held on September 4-5, 1997, in Bratislava, Slovakia.......This Special Issue of Analog Integrated Circuits and Signal Processing presents extended versions of selected papers from the First Electronic Circuits and Systems Conference (ECS'97) which was held on September 4-5, 1997, in Bratislava, Slovakia....

  17. Voyager-Jupiter radio science data papers (United States)

    Levy, G. S.; Wood, G. E.


    The reduction and interpretation of the radio science data from the Voyager 1 and 2 encounters of the planet Jupiter and its satellites resulted in the preparation of several papers for publication in the special Voyager-Jupiter issue of the Journal of Geophysical Research. The radio science and tracking systems of the Deep Space Network provide the data which makes this research possible. This article lists submitted papers by title, with their authors and with abstracts of their contents.

  18. Examining Motivations behind Paper Usage in Academia

    CERN Document Server

    Chakraborty, Joey


    We carried out a qualitative study to identify the "missing pieces" in current computing devices and technologies that are preventing people from eliminating paper from their lives. Most of the existing literature has looked into the work practices of businesses, while a few have researched how high school and college students and teaching assistants at universities work with paper. We were speci?cally interested in analysing paper use for people in the research side of academia, and seeing how our results compare to existing work. We recruited and interviewed participants from academia to understand what kind of tasks they use paper for, what kind of tasks they use computing devices for and what motivates them to use these two media. We found that, despite having access to at least one personal computing device, the participants preferred to work with paper in many situations. This appears to be attributed to certain intrinsic qualities that paper has, such as open format, easy navigation, readability, and t...

  19. Bacteria survival probability in bactericidal filter paper. (United States)

    Mansur-Azzam, Nura; Hosseinidoust, Zeinab; Woo, Su Gyeong; Vyhnalkova, Renata; Eisenberg, Adi; van de Ven, Theo G M


    Bactericidal filter papers offer the simplicity of gravity filtration to simultaneously eradicate microbial contaminants and particulates. We previously detailed the development of biocidal block copolymer micelles that could be immobilized on a filter paper to actively eradicate bacteria. Despite the many advantages offered by this system, its widespread use is hindered by its unknown mechanism of action which can result in non-reproducible outcomes. In this work, we sought to investigate the mechanism by which a certain percentage of Escherichia coli cells survived when passing through the bactericidal filter paper. Through the process of elimination, the possibility that the bacterial survival probability was controlled by the initial bacterial load or the existence of resistant sub-populations of E. coli was dismissed. It was observed that increasing the thickness or the number of layers of the filter significantly decreased bacterial survival probability for the biocidal filter paper but did not affect the efficiency of the blank filter paper (no biocide). The survival probability of bacteria passing through the antibacterial filter paper appeared to depend strongly on the number of collision between each bacterium and the biocide-loaded micelles. It was thus hypothesized that during each collision a certain number of biocide molecules were directly transferred from the hydrophobic core of the micelle to the bacterial lipid bilayer membrane. Therefore, each bacterium must encounter a certain number of collisions to take up enough biocide to kill the cell and cells that do not undergo the threshold number of collisions are expected to survive.

  20. 78 FR 56817 - Paper and Paper-Based Packaging Promotion, Research and Information Order; Referendum Procedures (United States)


    ... & Paper Association's 51st Annual Survey of Paper, Paperboard and Pulp, 2011. According to Customs data... quality strong pulp for making paper and paper-based packaging. (h) Linerboard means a grade of containerboard that is used as facing material in the manufacture of corrugated or solid fiber shipping boxes....

  1. 78 FR 211 - Paper and Paper-Based Packaging Promotion, Research and Information Order; Referendum Procedures (United States)


    ... corrugated or solid fiber shipping boxes. (i) Manufacture or produce means the process of transforming pulp... American Forest & Paper Association's 51st Annual Survey of Paper, Paperboard and Pulp, 2011. According to... process that transforms wood into a high quality strong pulp for making paper and paper-based...

  2. High-Grade Color Offset Paper of Xinya Paper Group Started Operation Successfully

    Institute of Scientific and Technical Information of China (English)


    On March 5th, the 3150 mm paper machine of Xinya Paper Group started the operation successfully. Originally, the paper machine produced ordinary culture paper, using mixed straw and wood pulp as the raw material. With the market demand shift toward higher quality, the original products produced can no longer meet the requirements.

  3. Supercritical fluid chromatography (SFC). Pt. 3. Applications

    Energy Technology Data Exchange (ETDEWEB)

    Leyendecker, D.; Hoefler, F.


    During the last few years, Supercritical Fluid Chromatography (SFC) has been emerged from an academic object of research to an important tool for the analytical chemist. Persuasive SFC-applications have been reported analyzing substrates with low volatilities, either due to high molecular weights or to high polarities, thermally or solvatolytically labile molecules, or analytes without chromophores or electroactive groups. Examples are oligomers and polymers up to a molecular weight of 10,000 g/mol, e.g., polysiloxanes, polyethers (nonionic surfactants), polyesters, polystyrenes and other vinyl polymers, polyenes etc. In addition, SFC is applicable to the analysis of several monomers. In the petroleum and coal industries, SFC was employed for the characterization of high boiling hydrocarbon mixtures as well as for group separations of alkanes, olefins, and aromatics. Due to the high solvent strength of supercritical fluids, several pesticides, herbicides, and fungicides can be determined either separately or in combination with polar metabolites. Physiologically active substances often are thermally labile and polar at the same time. SFC has been successfully applied to the analysis of steroids, prostaglandins, cannabinoids and other drugs, flavours, and medicines. It is also well suited for analyzing natural or synthetic mono-, di-, and triglycerides. (orig.).

  4. Gas chromatography using resistive heating technology. (United States)

    Wang, Anzi; Tolley, H Dennis; Lee, Milton L


    Air bath ovens are standard in conventional gas chromatography (GC) instruments because of their simplicity and reliability for column temperature control. However, their low heating rates, high power consumption and bulky size are in conflict with the increasing demands for fast separation and portable instrumentation. The deficiencies of air bath ovens can be eliminated using resistive heating technology, as the column is conductively heated by compact resistive heaters with low thermal mass. Resistive heating methods were employed in the early years of GC history, and they are emerging again as instrumentation is becoming more compact and sophisticated. Numerous designs have been tested and some have been successfully commercialized. Development of portable GC systems, including lab-on-a-chip devices, greatly benefits from the use of small, low-power resistive heating hardware. High speed GC separations using conventional instruments also can be best achieved with resistive heating modules. Despite some of its own inherent disadvantages, including efficiency loss, complex manufacturing and inconvenient column maintenance, resistive heating is expected to rapidly become a mature technology and even replace oven heating in the not-to-distant future.

  5. Optimizing heterosurface adsorbent synthesis for liquid chromatography (United States)

    Bogoslovskii, S. Yu.; Serdan, A. A.


    The structural and geometric parameters of a silica matrix (SM) for the synthesis of heterosurface adsorbents (HAs) are optimized. Modification is performed by shielding the external surfaces of alkyl-modified silica (AS) using human serum albumin and its subsequent crosslinking. The structural and geometric characteristics of the SM, AS, and HA are measured via low-temperature nitrogen adsorption. It is found that the structural characteristics of AS pores with diameters D 9 nm reduces significantly due to adsorption of albumin. It is concluded that silica gel with a maximum pore size distribution close to 5 nm and a minimal proportion of pores with D > 9 nm is optimal for HA synthesis; this allows us to achieve the greatest similarity between the chromatographic retention parameters for HA and AS. The suitability of the synthesized adsorbents for analyzing drugs in biological fluids through direct sample injection is confirmed by chromatography. It was found that the percentage of the protein fraction detected at the outlet of the chromatographic column is 98%.

  6. Vacuum ultraviolet detector for gas chromatography. (United States)

    Schug, Kevin A; Sawicki, Ian; Carlton, Doug D; Fan, Hui; McNair, Harold M; Nimmo, John P; Kroll, Peter; Smuts, Jonathan; Walsh, Phillip; Harrison, Dale


    Analytical performance characteristics of a new vacuum ultraviolet (VUV) detector for gas chromatography (GC) are reported. GC-VUV was applied to hydrocarbons, fixed gases, polyaromatic hydrocarbons, fatty acids, pesticides, drugs, and estrogens. Applications were chosen to feature the sensitivity and universal detection capabilities of the VUV detector, especially for cases where mass spectrometry performance has been limited. Virtually all chemical species absorb and have unique gas phase absorption cross sections in the approximately 120-240 nm wavelength range monitored. Spectra are presented, along with the ability to use software for deconvolution of overlapping signals. Some comparisons with experimental synchrotron data and computed theoretical spectra show good agreement, although more work is needed on appropriate computational methods to match the simultaneous broadband electronic and vibronic excitation initiated by the deuterium lamp. Quantitative analysis is governed by Beer-Lambert Law relationships. Mass on-column detection limits reported for representatives of different classes of analytes ranged from 15 (benzene) to 246 pg (water). Linear range measured at peak absorption for benzene was 3-4 orders of magnitude. Importantly, where absorption cross sections are known for analytes, the VUV detector is capable of absolute determination (without calibration) of the number of molecules present in the flow cell in the absence of chemical interferences. This study sets the stage for application of GC-VUV technology across a wide breadth of research areas.

  7. High Performance Liquid Chromatography of Vitamin A: A Quantitative Determination. (United States)

    Bohman, Ove; And Others


    Experimental procedures are provided for the quantitative determination of Vitamin A (retinol) in food products by analytical liquid chromatography. Standard addition and calibration curve extraction methods are outlined. (SK)

  8. A generalized theory of chromatography and multistep liquid extraction (United States)

    Chizhkov, V. P.; Boitsov, V. N.


    A generalized theory of chromatography and multistep liquid extraction is developed. The principles of highly efficient processes for fine preparative separation of binary mixture components on a fixed sorbent layer are discussed.

  9. Separation of neutral compounds by microemulsion electrokinetic chromatography

    DEFF Research Database (Denmark)

    Gabel-Jensen, Charlotte; Hansen, Steen Honore'; Pedersen-Bjergaard, S


    The selectivity of microemulsion electrokinetic chromatography (MEEKC) was studied utilizing some uncharged model compounds like aromatic amides, steroids, and esters of nicotinic acid. The cosurfactant of the microemulsion was found to be the most important factor affecting the selectivity...

  10. An Empirical Formula From Ion Exchange Chromatography and Colorimetry. (United States)

    Johnson, Steven D.


    Presents a detailed procedure for finding an empirical formula from ion exchange chromatography and colorimetry. Introduces students to more varied techniques including volumetric manipulation, titration, ion-exchange, preparation of a calibration curve, and the use of colorimetry. (JRH)

  11. Ion Chromatography: An Account of Its Conception and Early Development (United States)

    Small, Hamish


    The conception of ion chromatography and its development into a technique ready for commercialization is described. The pioneering development pointed the way to make ion exclusion an important member of the repertoire of IC methods.

  12. Measurement of Orotic Acid in Urine by Supercritical Fluid Chromatography

    Institute of Scientific and Technical Information of China (English)


    This work presents a simple, rapid and reliable supercritical fluid chromatography (SFC) method for a sensitive measurement of orotic acid in human urine. The samples were diluted with deionized water and analyzed directly without any pretreatment.

  13. Mixed Stationary Liquid Phases for Gas-Liquid Chromatography. (United States)

    Koury, Albert M.; Parcher, Jon F.


    Describes a laboratory technique for use in an undergraduate instrumental analysis course that, using the interpretation of window diagrams, prepares a mixed liquid phase column for gas-liquid chromatography. A detailed procedure is provided. (BT)

  14. Development of gas chromatography analysis of fatty acids in marine organisms. (United States)

    Tang, Baokun; Row, Kyung Ho


    The gas chromatographic analysis of fatty acids has attracted considerable interest. In this analysis, the common derivatives of fatty acids, such as fatty acid methyl esters, can be detected using a flame ionization detector and the mass spectra can indicate the true structure of fatty acids. This paper reviews gas chromatographic methods for obtaining fatty acids from marine organisms. The stationary phase and detector for applications in gas chromatography are discussed. This article also reviews the components of fatty acids in marine animals, marine plants and marine microorganisms.

  15. Chromatography methods in investigation of lipophilicity of the biological active substances

    Directory of Open Access Journals (Sweden)

    Odović Jadranka V.


    Full Text Available This paper presents the review of the methods used in research of the biological active substances hydrophobicity, a very important property. The biological activity of some substances depends on their pharmacokinetics and pharmacodynamics. These processes depend on the molecule's capability to interact with two different media: aqueous (cells interior and non-aqueous (cells membrane, or on the molecule lipophilicity. Today, great attention is given to investigation and systematic determination of drugs lipophilicity. In these researches chromatography methods have an important role.

  16. Identification of the Isotherm Function in Chromatography Using CMA-ES

    CERN Document Server

    Jebalia, Mohamed; Schoenauer, Marc; James, Francois; Postel, Marie


    This paper deals with the identification of the flux for a system of conservation laws in the specific example of analytic chromatography. The fundamental equations of chromatographic process are highly non linear. The state-of-the-art Evolution Strategy, CMA-ES (the Covariance Matrix Adaptation Evolution Strategy), is used to identify the parameters of the so-called isotherm function. The approach was validated on different configurations of simulated data using either one, two or three components mixtures. CMA-ES is then applied to real data cases and its results are compared to those of a gradient-based strategy.

  17. Impurity profiling and in-process testing of drugs for injection by fast liquid chromatography

    Institute of Scientific and Technical Information of China (English)

    Marie-Josee Rocheleau; Elaine Larouche; Cristina Salamu; Mihaela Curca


    Liquid chromatography (LC) is considered by many as a mature technique. Nonetheless, LC technology continues to evolve driven by the need for high-throughput and high-resolution analyses. Over the past several years, small particle size packing materials have been introduced by several column manufacturers to enable fast and efficient LC separations. Several examples of pharmaceutical analyses, including impurity profiling of taxanes and atracurium besylate, in-process testing of peptides in injectable dosage form, using sub-2 um column technology are presented in this paper, demonstrating some of the capabilities and limitations of the technology.

  18. Effect of acidity of drugs on the prediction of human oral absorption by biopartitioning micellar chromatography

    Institute of Scientific and Technical Information of China (English)


    Biopartitioning micellar chromatography(BMC)is a potentially high throughput and low cost alternative for in vitro prediction of drug absorption,which can mimic the drug partitioning process in biological systems.In this paper,a data set of 56 compounds representing acidic,basic,neutral and amphoteric drugs from various structure classes with human oral absorption(HOA)data available were employed to show the effect of acidity of drugs in oral absorption prediction.HOA was reciprocally correlated to the nega...

  19. Determination of preservatives in cosmetics, cleaning agents and pharmaceuticals using fast liquid chromatography. (United States)

    Baranowska, Irena; Wojciechowska, Iwona; Solarz, Natalia; Krutysza, Ewa


    This paper reports the development of a method for simultaneously determining five preservatives in cosmetics, cleaning agents and pharmaceuticals by fast liquid chromatography. Methylisothiazolinone, methylchloroisothiazolinone, benzyl alcohol, sodium benzoate and methylparaben were separated on a Chromolith Fast Gradient reversed-phase 18e column using gradient elution with acetonitrile and a 0.1% aqueous solution of formic acid, with a run time of 3 min. The preparation of solid and liquid samples included ultrasonic extraction with methanol with recoveries ranging from 69 to 119%. The developed method was used to analyze samples of cosmetics (66 samples), cleaning agents (five samples) and pharmaceutical industry products (17 samples).

  20. Continuous jute fibre reinforced laminated paper composite and reinforcement-fibre free paper laminate

    Indian Academy of Sciences (India)

    B B Verma


    Plastic bags create a serious environmental problem. The proposed jute fibre reinforced laminated paper composite and reinforcement-fibre free paper laminate may help to combat the war against this pollutant to certain extent. The paper laminate, without reinforcement fibre, exhibited a few fold superiority in tensile properties than single paper strip. The studies further show that an appreciable improvement in tensile properties can be achieved by introducing continuous jute fibre in paper laminates.