WorldWideScience

Sample records for chemical analysis

  1. Chemical Security Analysis Center

    Data.gov (United States)

    Federal Laboratory Consortium — In 2006, by Presidential Directive, DHS established the Chemical Security Analysis Center (CSAC) to identify and assess chemical threats and vulnerabilities in the...

  2. Chemical exchange program analysis.

    Energy Technology Data Exchange (ETDEWEB)

    Waffelaert, Pascale

    2007-09-01

    As part of its EMS, Sandia performs an annual environmental aspects/impacts analysis. The purpose of this analysis is to identify the environmental aspects associated with Sandia's activities, products, and services and the potential environmental impacts associated with those aspects. Division and environmental programs established objectives and targets based on the environmental aspects associated with their operations. In 2007 the most significant aspect identified was Hazardous Materials (Use and Storage). The objective for Hazardous Materials (Use and Storage) was to improve chemical handling, storage, and on-site movement of hazardous materials. One of the targets supporting this objective was to develop an effective chemical exchange program, making a business case for it in FY07, and fully implementing a comprehensive chemical exchange program in FY08. A Chemical Exchange Program (CEP) team was formed to implement this target. The team consists of representatives from the Chemical Information System (CIS), Pollution Prevention (P2), the HWMF, Procurement and the Environmental Management System (EMS). The CEP Team performed benchmarking and conducted a life-cycle analysis of the current management of chemicals at SNL/NM and compared it to Chemical Exchange alternatives. Those alternatives are as follows: (1) Revive the 'Virtual' Chemical Exchange Program; (2) Re-implement a 'Physical' Chemical Exchange Program using a Chemical Information System; and (3) Transition to a Chemical Management Services System. The analysis and benchmarking study shows that the present management of chemicals at SNL/NM is significantly disjointed and a life-cycle or 'Cradle-to-Grave' approach to chemical management is needed. This approach must consider the purchasing and maintenance costs as well as the cost of ultimate disposal of the chemicals and materials. A chemical exchange is needed as a mechanism to re-apply chemicals on site. This

  3. Chemical process hazards analysis

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1996-02-01

    The Office of Worker Health and Safety (EH-5) under the Assistant Secretary for the Environment, Safety and Health of the US Department (DOE) has published two handbooks for use by DOE contractors managing facilities and processes covered by the Occupational Safety and Health Administration (OSHA) Rule for Process Safety Management of Highly Hazardous Chemicals (29 CFR 1910.119), herein referred to as the PSM Rule. The PSM Rule contains an integrated set of chemical process safety management elements designed to prevent chemical releases that can lead to catastrophic fires, explosions, or toxic exposures. The purpose of the two handbooks, ``Process Safety Management for Highly Hazardous Chemicals`` and ``Chemical Process Hazards Analysis,`` is to facilitate implementation of the provisions of the PSM Rule within the DOE. The purpose of this handbook ``Chemical Process Hazards Analysis,`` is to facilitate, within the DOE, the performance of chemical process hazards analyses (PrHAs) as required under the PSM Rule. It provides basic information for the performance of PrHAs, and should not be considered a complete resource on PrHA methods. Likewise, to determine if a facility is covered by the PSM rule, the reader should refer to the handbook, ``Process Safety Management for Highly Hazardous Chemicals`` (DOE- HDBK-1101-96). Promulgation of the PSM Rule has heightened the awareness of chemical safety management issues within the DOE. This handbook is intended for use by DOE facilities and processes covered by the PSM rule to facilitate contractor implementation of the PrHA element of the PSM Rule. However, contractors whose facilities and processes not covered by the PSM Rule may also use this handbook as a basis for conducting process hazards analyses as part of their good management practices. This handbook explains the minimum requirements for PrHAs outlined in the PSM Rule. Nowhere have requirements been added beyond what is specifically required by the rule.

  4. Radiometric chemical analysis

    International Nuclear Information System (INIS)

    The radiometric method of analysis is noted for its sensitivity and its simplicity in both apparatus and procedure. A few inexpensive radioactive reagents permit the analysis of a wide variety of chemical elements and compounds. Any particular procedure is generally applicable over a very wide range of concentrations. It is potentially an analytical method of great industrial significance. Specific examples of analyses are cited to illustrate the potentialities of ordinary equipment. Apparatus specifically designed for radiometric chemistry may shorten the time required, and increase the precision and accuracy for routine analyses. A sensitive and convenient apparatus for the routine performance of radiometric chemical analysis is a special type of centrifuge which has been used in obtaining the data presented in this paper. The radioactivity of the solution is measured while the centrifuge is spinning. This device has been used as the basis for an automatic analyser for phosphate ion, programmed to follow a sequence of unknown sampling, reagent mixing, centrifugation, counting data presentation, and phosphate replenishment. This analyser can repeatedly measure phosphate-concentration in the range of 5 to 50 ppm with an accuracy of ±5%. (author)

  5. Chemical Analysis Facility

    Data.gov (United States)

    Federal Laboratory Consortium — FUNCTION: Uses state-of-the-art instrumentation for qualitative and quantitative analysis of organic and inorganic compounds, and biomolecules from gas, liquid, and...

  6. Microprocessors in automatic chemical analysis

    International Nuclear Information System (INIS)

    Application of microprocessors to programming and computing of solutions chemical analysis by a sequential technique is examined. Safety, performances reliability are compared to other methods. An example is given on uranium titration by spectrophotometry

  7. Chemical substructure analysis in toxicology

    Energy Technology Data Exchange (ETDEWEB)

    Beauchamp, R.O. Jr. [Center for Information on Toxicology and Environment, Raleigh, NC (United States)

    1990-12-31

    A preliminary examination of chemical-substructure analysis (CSA) demonstrates the effective use of the Chemical Abstracts compound connectivity file in conjunction with the bibliographic file for relating chemical structures to biological activity. The importance of considering the role of metabolic intermediates under a variety of conditions is illustrated, suggesting structures that should be examined that may exhibit potential activity. This CSA technique, which utilizes existing large files accessible with online personal computers, is recommended for use as another tool in examining chemicals in drugs. 2 refs., 4 figs.

  8. Chemical Analysis of Single Cells

    Science.gov (United States)

    Borland, Laura M.; Kottegoda, Sumith; Phillips, K. Scott; Allbritton, Nancy L.

    2008-07-01

    Chemical analysis of single cells requires methods for quickly and quantitatively detecting a diverse array of analytes from extremely small volumes (femtoliters to nanoliters) with very high sensitivity and selectivity. Microelectrophoretic separations, using both traditional capillary electrophoresis and emerging microfluidic methods, are well suited for handling the unique size of single cells and limited numbers of intracellular molecules. Numerous analytes, ranging from small molecules such as amino acids and neurotransmitters to large proteins and subcellular organelles, have been quantified in single cells using microelectrophoretic separation techniques. Microseparation techniques, coupled to varying detection schemes including absorbance and fluorescence detection, electrochemical detection, and mass spectrometry, have allowed researchers to examine a number of processes inside single cells. This review also touches on a promising direction in single cell cytometry: the development of microfluidics for integrated cellular manipulation, chemical processing, and separation of cellular contents.

  9. Optical MEMS for chemical analysis and biomedicine

    CERN Document Server

    Jiang, Hongrui

    2016-01-01

    This book describes the current state of optical MEMS in chemical and biomedical analysis and brings together current trends and highlights topics representing the most exciting progress in recent years in the field.

  10. 40 CFR 761.253 - Chemical analysis.

    Science.gov (United States)

    2010-07-01

    ... 40 Protection of Environment 30 2010-07-01 2010-07-01 false Chemical analysis. 761.253 Section 761.253 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) TOXIC SUBSTANCES CONTROL ACT... analysis. (a) Extract PCBs from the standard wipe sample collection medium and clean-up the extracted...

  11. Chemical analysis of high purity graphite

    International Nuclear Information System (INIS)

    The Sub-Committee on Chemical Analysis of Graphite was organized in April 1989, under the Committee on Chemical Analysis of Nuclear Fuels and Reactor Materials, JAERI. The Sub-Committee carried out collaborative analyses among eleven participating laboratories for the certification of the Certified Reference Materials (CRMs), JAERI-G5 and G6, after developing and evaluating analytical methods during the period of September 1989 to March 1992. The certified values were given for ash, boron and silicon in the CRM based on the collaborative analysis. The values for ten elements (Al, Ca, Cr, Fe, Mg, Mo, Ni, Sr, Ti, V) were not certified, but given for information. Preparation, homogeneity testing and chemical analyses for certification of reference materials were described in this paper. (author) 52 refs

  12. Spectroscopic chemical analysis methods and apparatus

    Science.gov (United States)

    Hug, William F. (Inventor); Reid, Ray D. (Inventor); Bhartia, Rohit (Inventor)

    2013-01-01

    Spectroscopic chemical analysis methods and apparatus are disclosed which employ deep ultraviolet (e.g. in the 200 nm to 300 nm spectral range) electron beam pumped wide bandgap semiconductor lasers, incoherent wide bandgap semiconductor light emitting devices, and hollow cathode metal ion lasers to perform non-contact, non-invasive detection of unknown chemical analytes. These deep ultraviolet sources enable dramatic size, weight and power consumption reductions of chemical analysis instruments. Chemical analysis instruments employed in some embodiments include capillary and gel plane electrophoresis, capillary electrochromatography, high performance liquid chromatography, flow cytometry, flow cells for liquids and aerosols, and surface detection instruments. In some embodiments, Raman spectroscopic detection methods and apparatus use ultra-narrow-band angle tuning filters, acousto-optic tuning filters, and temperature tuned filters to enable ultra-miniature analyzers for chemical identification. In some embodiments Raman analysis is conducted along with photoluminescence spectroscopy (i.e. fluorescence and/or phosphorescence spectroscopy) to provide high levels of sensitivity and specificity in the same instrument.

  13. Service activities of chemical analysis division

    International Nuclear Information System (INIS)

    Progress of the Division during the year of 1988 was described on the service activities for various R and D projects carrying out in the Institute, for the fuel fabrication and conversion plant, and for the post-irradiation examination facility. Relevant analytical methodologies developed for the chemical analysis of an irradiated fuel, safeguards chemical analysis, and pool water monitoring were included such as chromatographic separation of lanthanides, polarographic determination of dissolved oxygen in water, and automation on potentiometric titration of uranium. Some of the laboratory manuals revised were also included in this progress report. (Author)

  14. Chemical abundance analysis of 19 barium stars

    CERN Document Server

    Yang, G C; Spite, M; Chen, Y Q; Zhao, G; Zhang, B; Liu, G Q; Liu, Y J; Liu, N; Deng, L C; Spite, F; Hill, V; Zhang, C X

    2016-01-01

    We aim at deriving accurate atmospheric parameters and chemical abundances of 19 barium (Ba) stars, including both strong and mild Ba stars, based on the high signal-to-noise ratio and high resolution Echelle spectra obtained from the 2.16 m telescope at Xinglong station of National Astronomical Observatories, Chinese Academy of Sciences. The chemical abundances of the sample stars were obtained from an LTE, plane-parallel and line-blanketed atmospheric model by inputting the atmospheric parameters (effective temperatures, surface gravities, metallicity and microturbulent velocity) and equivalent widths of stellar absorption lines. These samples of Ba stars are giants indicated by atmospheric parameters, metallicities and kinematic analysis about UVW velocity. Chemical abundances of 17 elements were obtained for these Ba stars. Their light elements (O, Na, Mg, Al, Si, Ca, Sc, Ti, V, Cr, Mn and Ni) are similar to the solar abundances. Our samples of Ba stars show obvious overabundances of neutron-capture (n-ca...

  15. Chemical detection, identification, and analysis system

    International Nuclear Information System (INIS)

    The chemical detection, identification, and analysis system (CDIAS) has three major goals. The first is to display safety information regarding chemical environment before personnel entry. The second is to archive personnel exposure to the environment. Third, the system assists users in identifying the stage of a chemical process in progress and suggests safety precautions associated with that process. In addition to these major goals, the system must be sufficiently compact to provide transportability, and it must be extremely simple to use in order to keep user interaction at a minimum. The system created to meet these goals includes several pieces of hardware and the integration of four software packages. The hardware consists of a low-oxygen, carbon monoxide, explosives, and hydrogen sulfide detector; an ion mobility spectrometer for airborne vapor detection; and a COMPAQ 386/20 portable computer. The software modules are a graphics kernel, an expert system shell, a data-base management system, and an interface management system. A supervisory module developed using the interface management system coordinates the interaction of the other software components. The system determines the safety of the environment using conventional data acquisition and analysis techniques. The low-oxygen, carbon monoxide, hydrogen sulfide, explosives, and vapor detectors are monitored for hazardous levels, and warnings are issued accordingly

  16. Analysis of Chemical Technology Division waste streams

    International Nuclear Information System (INIS)

    This document is a summary of the sources, quantities, and characteristics of the wastes generated by the Chemical Technology Division (CTD) of the Oak Ridge National Laboratory. The major contributors of hazardous, mixed, and radioactive wastes in the CTD as of the writing of this document were the Chemical Development Section, the Isotopes Section, and the Process Development Section. The objectives of this report are to identify the sources and the summarize the quantities and characteristics of hazardous, mixed, gaseous, and solid and liquid radioactive wastes that are generated by the Chemical Technology Division (CTD) of the Oak Ridge National Laboratory (ORNL). This study was performed in support of the CTD waste-reduction program -- the goals of which are to reduce both the volume and hazard level of the waste generated by the division. Prior to the initiation of any specific waste-reduction projects, an understanding of the overall waste-generation system of CTD must be developed. Therefore, the general approach taken in this study is that of an overall CTD waste-systems analysis, which is a detailed presentation of the generation points and general characteristics of each waste stream in CTD. The goal of this analysis is to identify the primary waste generators in the division and determine the most beneficial areas to initiate waste-reduction projects. 4 refs., 4 figs., 13 tabs

  17. VALIDATION GUIDELINES FOR LABORATORIES PERFORMING FORENSIC ANALYSIS OF CHEMICAL TERRORISM

    Science.gov (United States)

    The Scientific Working Group on Forensic Analysis of Chemical Terrorism (SWGFACT) has developed the following guidelines for laboratories engaged in the forensic analysis of chemical evidence associated with terrorism. This document provides a baseline framework and guidance for...

  18. Systems analysis of past, present, and future chemical terrorism scenarios.

    Energy Technology Data Exchange (ETDEWEB)

    Hoette, Trisha Marie

    2012-03-01

    Throughout history, as new chemical threats arose, strategies for the defense against chemical attacks have also evolved. As a part of an Early Career Laboratory Directed Research and Development project, a systems analysis of past, present, and future chemical terrorism scenarios was performed to understand how the chemical threats and attack strategies change over time. For the analysis, the difficulty in executing chemical attack was evaluated within a framework of three major scenario elements. First, historical examples of chemical terrorism were examined to determine how the use of chemical threats, versus other weapons, contributed to the successful execution of the attack. Using the same framework, the future of chemical terrorism was assessed with respect to the impact of globalization and new technologies. Finally, the efficacy of the current defenses against contemporary chemical terrorism was considered briefly. The results of this analysis justify the need for continued diligence in chemical defense.

  19. Chemical abundance analysis of 19 barium stars

    Science.gov (United States)

    Yang, Guo-Chao; Liang, Yan-Chun; Spite, Monique; Chen, Yu-Qin; Zhao, Gang; Zhang, Bo; Liu, Guo-Qing; Liu, Yu-Juan; Liu, Nian; Deng, Li-Cai; Spite, Francois; Hill, Vanessa; Zhang, Cai-Xia

    2016-01-01

    We aim at deriving accurate atmospheric parameters and chemical abundances of 19 barium (Ba) stars, including both strong and mild Ba stars, based on the high signal-to-noise ratio and high resolution Echelle spectra obtained from the 2.16 m telescope at Xinglong station of National Astronomical Observatories, Chinese Academy of Sciences. The chemical abundances of the sample stars were obtained from an LTE, plane-parallel and line-blanketed atmospheric model by inputting the atmospheric parameters (effective temperatures Teff, surface gravities log g, metallicity [Fe/H] and microturbulence velocity ξt) and equivalent widths of stellar absorption lines. These samples of Ba stars are giants as indicated by atmospheric parameters, metallicities and kinematic analysis about UVW velocity. Chemical abundances of 17 elements were obtained for these Ba stars. Their Na, Al, α- and iron-peak elements (O, Na, Mg, Al, Si, Ca, Sc, Ti, V, Cr, Mn, Ni) are similar to the solar abundances. Our samples of Ba stars show obvious overabundances of neutron-capture (n-capture) process elements relative to the Sun. Their median abundances of [Ba/Fe], [La/Fe] and [Eu/Fe] are 0.54, 0.65 and 0.40, respectively. The Y I and Zr I abundances are lower than Ba, La and Eu, but higher than the α- and iron-peak elements for the strong Ba stars and similar to the iron-peak elements for the mild stars. There exists a positive correlation between Ba intensity and [Ba/Fe]. For the n-capture elements (Y, Zr, Ba, La), there is an anti-correlation between their [X/Fe] and [Fe/H]. We identify nine of our sample stars as strong Ba stars with [Ba/Fe] >0.6 where seven of them have Ba intensity Ba=2-5, one has Ba=1.5 and another one has Ba=1.0. The remaining ten stars are classified as mild Ba stars with 0.17<[Ba/Fe] <0.54.

  20. Spectroscopic Chemical Analysis Methods and Apparatus

    Science.gov (United States)

    Hug, William F.; Reid, Ray D.

    2012-01-01

    This invention relates to non-contact spectroscopic methods and apparatus for performing chemical analysis and the ideal wavelengths and sources needed for this analysis. It employs deep ultraviolet (200- to 300-nm spectral range) electron-beam-pumped wide bandgap semiconductor lasers, incoherent wide bandgap semiconductor lightemitting devices, and hollow cathode metal ion lasers. Three achieved goals for this innovation are to reduce the size (under 20 L), reduce the weight [under 100 lb (.45 kg)], and reduce the power consumption (under 100 W). This method can be used in microscope or macroscope to provide measurement of Raman and/or native fluorescence emission spectra either by point-by-point measurement, or by global imaging of emissions within specific ultraviolet spectral bands. In other embodiments, the method can be used in analytical instruments such as capillary electrophoresis, capillary electro-chromatography, high-performance liquid chromatography, flow cytometry, and related instruments for detection and identification of unknown analytes using a combination of native fluorescence and/or Raman spectroscopic methods. This design provides an electron-beampumped semiconductor radiation-producing method, or source, that can emit at a wavelength (or wavelengths) below 300 nm, e.g. in the deep ultraviolet between about 200 and 300 nm, and more preferably less than 260 nm. In some variations, the method is to produce incoherent radiation, while in other implementations it produces laser radiation. In some variations, this object is achieved by using an AlGaN emission medium, while in other implementations a diamond emission medium may be used. This instrument irradiates a sample with deep UV radiation, and then uses an improved filter for separating wavelengths to be detected. This provides a multi-stage analysis of the sample. To avoid the difficulties related to producing deep UV semiconductor sources, a pumping approach has been developed that uses

  1. Current trends of the development of chemical analysis

    Directory of Open Access Journals (Sweden)

    Rema Matakova

    2014-12-01

    Full Text Available This paper presents dynamics of the development of all stages of chemical analysis during last 15 years. The ways of the quality improvement of chemical analysis and its considerable advancement into the field of trace concentrations of substances are shown. Features of development of analytical methods, modern techniques for concentration and separation of substances, as well as chemomerrical processing of results are analyzed. Huge importance of computerization and automation of the analysis is shown.

  2. Chemical Diversity, Origin, and Analysis of Phycotoxins

    DEFF Research Database (Denmark)

    Rasmussen, Silas Anselm; Andersen, Aaron John Christian; Andersen, Nikolaj Gedsted;

    2016-01-01

    Microalgae, particularly those from the lineage Dinoflagellata, are very well-known for their ability to produce phycotoxins that may accumulate in the marine food chain and eventually cause poisoning in humans. This includes toxins accumulating in shellfish, such as saxitoxin, okadaic acid......, yessotoxins, azaspiracids, brevetoxins, and pinnatoxins. Other toxins, such as ciguatoxins and maitotoxins, accumulate in fish, where, as is the case for the latter compounds, they can be metabolized to even more toxic metabolites. On the other hand, much less is known about the chemical nature of compounds...... complex natural compounds known to mankind, with chemical structures that show no resemblance to what has been characterized from plants, fungi, or bacteria. In addition, it will summarize algal species known to be related to fish-killing blooms, but from which ichthyotoxins are yet to be characterized....

  3. Hybrid chemical and nondestructive analysis technique

    International Nuclear Information System (INIS)

    A hybrid chemical/NDA technique has been applied at the Los Alamos National Laboratory to the assay of plutonium in ion-exchange effluents. Typical effluent solutions contain low concentrations of plutonium and high concentrations of americium. A simple trioctylphosphine oxide (TOPO) separation can remove 99.9% of the americium. The organic phase that contains the separated plutonium can be accurately assayed by monitoring the uranium L x-ray intensities

  4. Hybrid chemical and nondestructive-analysis technique

    Energy Technology Data Exchange (ETDEWEB)

    Hsue, S.T.; Marsh, S.F.; Marks, T.

    1982-01-01

    A hybrid chemical/NDA technique has been applied at the Los Alamos National Laboratory to the assay of plutonium in ion-exchange effluents. Typical effluent solutions contain low concentrations of plutonium and high concentrations of americium. A simple trioctylphosphine oxide (TOPO) separation can remove 99.9% of the americium. The organic phase that contains the separated plutonium can be accurately assayed by monitoring the uranium L x-ray intensities.

  5. Method for fractional solid-waste sampling and chemical analysis

    DEFF Research Database (Denmark)

    Riber, Christian; Rodushkin, I.; Spliid, Henrik;

    2007-01-01

    Chemical characterization of solid waste is a demanding task due to the heterogeneity of the waste. This article describes how 45 material fractions hand-sorted from Danish household waste were subsampled and prepared for chemical analysis of 61 substances. All material fractions were subject...

  6. EDXRF for non-destructive chemical analysis

    International Nuclear Information System (INIS)

    One of the non-destructive methods used for the identification and verification of metals is by the energy-dispersive X-ray fluorescence (EDXRF) technique. EDXRF analysis provides several important advantages such as simultaneous determination of the elements present, enable to analyse a very wide concentration range, fast analysis with no sample preparation. The paper shows how this technique is developed and applied in the identification and verification of different grades of stainless steels and also precious metals analysis. (Author)

  7. Tribology analysis of chemical-mechanical polishing

    Energy Technology Data Exchange (ETDEWEB)

    Runnels, S.R.; Eyman, L.M. (Sematech, Austin, TX (United States))

    1994-06-01

    To better understand the variation of material removal rate on a wafer during chemical-mechanical polishing (CMP), knowledge of the stress distribution on the wafer surface is required. The difference in wafer-surface stress distributions could be considerable depending on whether or not the wafer hydroplanes during polishing. This study analyzes the fluid film between the wafer and pad and demonstrates that hydroplaning is possible for standard CMP processes. The importance of wafer curvature, slurry viscosity, and rotation speed on the thickness of the fluid film is also demonstrated.

  8. Chemical equilibrium analysis of dry hydrogen combustion

    International Nuclear Information System (INIS)

    The present work is based on a thermo-chemical equilibrium model for studying the effect of combustion of hydrogen during postulated accident scenarios in nuclear reactor containments. This model is based on the method of element potentials which seeks to minimize the free energy of the system. The condition on internal energy balance is imposed as a constraint during the minimization process. Another simplified model purely based on the internal energy balance has also been implemented to investigate the isolated impact of free energy and the conditions under which it becomes dominant. The two models have been used to extract final pressures for a wide range of initial conditions and mixture compositions that are typically found during accident scenarios. In the absence of hydrogen combustion experimental data, such models will become important for laying down a first estimate on the possible outcomes. (author)

  9. Chemical aspects of nuclear methods of analysis

    International Nuclear Information System (INIS)

    This final report includes papers which fall into three general areas: development of practical pre-analysis separation techniques, uranium/thorium separation from other elements for analytical and processing operations, and theory and mechanism of separation techniques. A separate abstract was prepared for each of the 9 papers

  10. Airborne chemistry: acoustic levitation in chemical analysis.

    Science.gov (United States)

    Santesson, Sabina; Nilsson, Staffan

    2004-04-01

    This review with 60 references describes a unique path to miniaturisation, that is, the use of acoustic levitation in analytical and bioanalytical chemistry applications. Levitation of small volumes of sample by means of a levitation technique can be used as a way to avoid solid walls around the sample, thus circumventing the main problem of miniaturisation, the unfavourable surface-to-volume ratio. Different techniques for sample levitation have been developed and improved. Of the levitation techniques described, acoustic or ultrasonic levitation fulfils all requirements for analytical chemistry applications. This technique has previously been used to study properties of molten materials and the equilibrium shape()and stability of liquid drops. Temperature and mass transfer in levitated drops have also been described, as have crystallisation and microgravity applications. The airborne analytical system described here is equipped with different and exchangeable remote detection systems. The levitated drops are normally in the 100 nL-2 microL volume range and additions to the levitated drop can be made in the pL-volume range. The use of levitated drops in analytical and bioanalytical chemistry offers several benefits. Several remote detection systems are compatible with acoustic levitation, including fluorescence imaging detection, right angle light scattering, Raman spectroscopy, and X-ray diffraction. Applications include liquid/liquid extractions, solvent exchange, analyte enrichment, single-cell analysis, cell-cell communication studies, precipitation screening of proteins to establish nucleation conditions, and crystallisation of proteins and pharmaceuticals. PMID:14762640

  11. Black tea: chemical analysis and stability.

    Science.gov (United States)

    Li, Shiming; Lo, Chih-Yu; Pan, Min-Hsiung; Lai, Ching-Shu; Ho, Chi-Tang

    2013-01-01

    Tea is the most popular flavored and functional drink worldwide. The nutritional value of tea is mostly from the tea polyphenols that are reported to possess a broad spectrum of biological activities, including anti-oxidant properties, reduction of various cancers, inhibition of inflammation, and protective effects against diabetes, hyperlipidemia and obesity. Tea polyphenols include catechins and gallic acid in green and white teas, and theaflavins and thearubigins as well as other catechin polymers in black and oolong teas. Accurate analysis of black tea polyphenols plays a significant role in the identification of black tea contents, quality control of commercial tea beverages and extracts, differentiation of various contents of theaflavins and catechins and correlations of black tea identity and quality with biological activity, and most importantly, the establishment of the relationship between quantitative tea polyphenol content and its efficacy in animal or human studies. Global research in tea polyphenols has generated much in vitro and in vivo data rationally correlating tea polyphenols with their preventive and therapeutic properties in human diseases such as cancer, and metabolic and cardiovascular diseases etc. Based on these scientific findings, numerous tea products have been developed including flavored tea drinks, tea-based functional drinks, tea extracts and concentrates, and dietary supplements and food ingredients, demonstrating the broad applications of tea and its extracts, particularly in the field of functional food.

  12. Terahertz Chemical Analysis of Exhaled Human Breath - Broad Essay of Chemicals

    Science.gov (United States)

    Branco, Daniela R.; Fosnight, Alyssa M.; Thomas, Jessica R.; Medvedev, Ivan R.

    2013-06-01

    Approximately 3000 chemicals are thought to be present in human breath. Of these chemicals, many are considered typical of exhaled air. Yet, others can allude to different disease pathologies. The detection of chemicals in breath could have many practical purposes in medicine and provide a noninvasive means of diagnostics. We have previously reported on detection of ethanol, methanol, and acetone in exhaled human breath using a novel sub-millimeter/THz spectroscopic approach. This paper reports on our most recent study. A tentative list has been made of approximately 20 chemicals previously found in breath using other methods. Though many of these chemicals are only expressed in samples from donors with certain pathologies, at the time of this submission we are able to detect and quantitatively measure acetaldehyde and dimethyl sulfide in the breath of several healthy donors. Additional tentatively identified chemicals have been seen using this approach. This presentation will explain our experimental procedures and present our most recent results in THz breath analysis. Prospects, challenges and future plans will be outlined and discussed.

  13. A review of chemical gradient systems for cell analysis.

    Science.gov (United States)

    Somaweera, Himali; Ibraguimov, Akif; Pappas, Dimitri

    2016-02-11

    Microfluidic spatial and temporal gradient generators have played an important role in many biological assays such as in the analysis of wound healing, inflammation, and cancer metastasis. Chemical gradient systems can also be applied to other fields such as drug design, chemical synthesis, chemotaxis, etc. Microfluidic systems are particularly amenable to gradient formation, as the length scales used in chips enable fluid processes that cannot be conducted in bulk scale. In this review we discuss new microfluidic devices for gradient generation and applications of those systems in cell analysis.

  14. Gradient Bundle Analysis: A Full Topological Approach to Chemical Bonding

    CERN Document Server

    Morgenstern, Amanda

    2016-01-01

    The "chemical bond" is a central concept in molecular sciences, but there is no consensus as to what a bond actually is. Therefore, a variety of bonding models have been developed, each defining the structure of molecules in a different manner with the goal of explaining and predicting chemical properties. This thesis describes the initial development of gradient bundle analysis (GBA), a chemical bonding model that creates a high resolution picture of chemical interactions within the charge density framework. GBA is based on concepts from the quantum theory of atoms in molecules (QTAIM), but uses a more complete picture of the topology and geometry of the electron charge density to understand and predict bonding interactions. Gradient bundles are defined as volumes bounded by zero-flux surfaces (ZFSs) in the gradient of the charge density with well-defined energies. The structure of gradient bundles provides an avenue for detecting the locations of valence electrons, which correspond to reactive regions in a ...

  15. Surface chemical composition analysis of heat-treated bamboo

    Science.gov (United States)

    Meng, Fan-dan; Yu, Yang-lun; Zhang, Ya-mei; Yu, Wen-ji; Gao, Jian-min

    2016-05-01

    In this study, the effect of heat treatment on the chemical composition of bamboo slivers was studied. The chemical properties of the samples were examined by chemical analysis. Results showed a decrease in the contents of holocellulose and α-cellulose, as well as an increase in the contents of lignin and extractives. Changes in the chemical structure of bamboo components were analyzed by Fourier transform infrared spectroscopy (FTIR) and X-ray photoelectron spectroscopy (XPS). FTIR spectroscopy results indicated that hemicellulose contents decrease, whereas lignin contents increase after heat treatment. Ester formation linked to lignin decreased the hygroscopicity of the bamboo samples and consequently improved their dimensional stability and durability. XPS spectroscopy results showed that hemicelluloses and celluloses are relatively more sensitive to the heating process than lignin. As a consequence, hemicellulose and cellulose contents decreased, whereas lignin contents increased during heat treatment. The results obtained in this study provide useful information for the future utilization of heat-treated bamboo.

  16. Chemical analysis of Ginkgo biloba leaves and extracts

    NARCIS (Netherlands)

    Beek, van T.A.

    2002-01-01

    The chemical analysis and quality control of Ginkgo leaves and extracts is reviewed. Important constituents present in the medicinally used leaves are the terpene trilactones, i.e., ginkgolides A, B, C, J and bilobalide, many flavonol glycosides, biflavones, proanthocyanidins, alkylphenols, simple p

  17. Shotgun lipidomic analysis of chemically sulfated sterols compromises analytical sensitivity

    DEFF Research Database (Denmark)

    Casanovas, Albert; Hannibal-Bach, Hans Kristian; Jensen, Ole Nørregaard;

    2014-01-01

    Fourier transform mass spectrometry (FTMS) for identification and quantification of lipid species [6]. Shotgun lipidomics affords extensive lipidome coverage by combining the analysis of lipid extracts in positive and negative ion mode [1, 3]. Notably, sterols such as cholesterol and ergosterol exhibit...... low ionization efficiency in ESI [7]. For this reason, chemical derivatization procedures including acetylation [8] or sulfation [9] are commonly implemented to facilitate ionization, detection and quantification of sterols for global lipidome analysis [1-3, 10]....

  18. Near-field Optical Imagigng and Chemical Analysis

    Science.gov (United States)

    Andres, La Rosa

    1998-03-01

    Identification of molecular structures in complex mixtures represents a major challenge in chemical research today. Microfabricated devices or lab-on-a-chip that perform chemical analysis allows dynamic sampling of picoliter microenvironments and separation. The long-term goals of nanochemistry down to the femtoliter scale involve refinement of the detection limit to single-molecule. Our approach consists in designing a very sensitive near-field optical microscope (NSOM-SIAM) to explore the mesoscopic properties of organic compounds. The validity, sensitivity and unique spatial resolution of this system will be discussed for multiple analyte chemosensing.

  19. An Extended Algorithm of Flexibility Analysis in Chemical Engineering Processes

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    An extended algorithm of flexibility analysis with a local adjusting method for flexibility region of chemical processes, which is based on the active constraint strategy, is proposed, which fully exploits the flexibility region of the process system operation. The hyperrectangular flexibility region determined by the extended algorithm is larger than that calculated by the previous algorithms. The limitation of the proposed algorithm due to imperfect convexity and its corresponding verification measure are also discussed. Both numerical and actual chemical process examples are presented to demonstrate the effectiveness of the new algorithm.

  20. The Impact of Flow Injection on Modern Chemical Analysis

    DEFF Research Database (Denmark)

    Hansen, Elo Harald

    There is no doubt that Flow Injection Analysis (FIA) has had a profound impact on the ways and means that modern analytical chemical procedures are performed. This is amply reflected in the voluminous scientific literature, which by the middle of 2004 passed more than 14,500 FIA-publications in i......There is no doubt that Flow Injection Analysis (FIA) has had a profound impact on the ways and means that modern analytical chemical procedures are performed. This is amply reflected in the voluminous scientific literature, which by the middle of 2004 passed more than 14,500 FIA...... and preconcentration procedures. In recent years, FIA has been supplemented by Sequential Injection Analysis (SIA) and the Lab-on-Valve (LOV) approach. Following a brief historic introduction and an account of the impact of FIA in academia, the lecture will describe these two new generations of FIA, accompanied...

  1. Chemical analysis of thin films at Sandia National Laboratories

    International Nuclear Information System (INIS)

    The characterization of thin films produced by chemical and physical vapor deposition requires special analytical techniques. When the average compositions of the films are required, dissolution of the thin films and measurement of the concentrations of the solubilized species is the appropriate analytical approach. In this report techniques for the wet chemical analysis of thin films of Si:Al, P2O5:SiO2, B2O3:SiO2, TiB/sub x/ and TaB/sub x/ are described. The analyses are complicated by the small total quantities of these analytes present in the films, the refractory characters of these analytes, and the possibility of interferences from the substrates on which the films are deposited. Etching conditions are described which dissolve the thin films without introducing interferences from the substrates. A chemical amplification technique and inductively coupled plasma atomic emission spectrometry are shown to provide the sensitivity required to measure the small total quantities (micrograms to milligrams) of analytes present. Also the chemical analysis data has been used to calibrate normal infrared absorption spectroscopy to give fast estimates of the phosphorus and/or boron dopant levels in thin SiO2 films

  2. Cluster analysis to evaluate stable chemical elements and physical-chemical parameters behavior on uranium mining waste

    International Nuclear Information System (INIS)

    The Ore Treating Unit (UTM, in portuguese) is a deactivated uranium mine. A cluster analysis was used to evaluate the behavior of stable chemical elements and physical-chemical parameters in their effluents. The utilization of the cluster analysis proved itself effective in the assessment, allowing the identification of groups of chemical elements, physical-chemical parameters and their joint analysis (elements and parameters). As a result we may assert, based on data analysis, that there is a strong link between calcium and magnesium and between aluminum and rare-earth oxides on UTM's effluents. Sulphate was also identified as strongly linked to total and dissolved solids, and those to electrical conductivity. There were other associations, but not so strongly linked. Further gathering, to seasonal evaluation, are required in order to confirm those analysis. Additional statistical analysis (factor analysis) must be used to try to identify the origin of the identified groups on this analysis. (author)

  3. Device for high spatial resolution chemical analysis of a sample and method of high spatial resolution chemical analysis

    Science.gov (United States)

    Van Berkel, Gary J.

    2015-10-06

    A system and method for analyzing a chemical composition of a specimen are described. The system can include at least one pin; a sampling device configured to contact a liquid with a specimen on the at least one pin to form a testing solution; and a stepper mechanism configured to move the at least one pin and the sampling device relative to one another. The system can also include an analytical instrument for determining a chemical composition of the specimen from the testing solution. In particular, the systems and methods described herein enable chemical analysis of specimens, such as tissue, to be evaluated in a manner that the spatial-resolution is limited by the size of the pins used to obtain tissue samples, not the size of the sampling device used to solubilize the samples coupled to the pins.

  4. Electrochemical approaches for chemical and biological analysis on Mars

    Science.gov (United States)

    Kounaves, Samuel P.

    2003-01-01

    Obtaining in situ chemical data from planetary bodies such as Mars or Europa can present significant challenges. The one analytical technique that has many of the requisite characteristics to meet such a challenge is electroanalysis. Described here are three electroanalytical devices designed for in situ geochemical and biological analysis on Mars. The Mars Environmental Compatibility Assessment (MECA) was built and flight qualified for the now cancelled NASA Mars 2001 Lander. Part of MECA consisted of four "cells" containing arrays of electrochemical based sensors for measuring the ionic species in soil samples. A next-generation MECA, the Robotic Chemical Analysis Laboratory (RCAL), uses a carousel-type system to allow for greater customization of analytical procedures. A second instrument, proposed as part of the 2007 CryoScout mission, consists of a flow-through inorganic chemical analyzer (MICA). CryoScout is a torpedo-like device designed for subsurface investigation of the stratigraphic climate record embedded in Mars' north polar cap. As the CryoScout melts its way through the ice cap, MICA will collect and analyze the meltwater for a variety of inorganics and chemical parameters. By analyzing the chemistry locked in the layers of dust, salt, and ice, geologists will be able to determine the recent history of climate, water, and atmosphere on Mars and link it to the past. Finally, electroanalysis shows its abilities in the detection of possible microorganism on Mars or elsewhere in the solar system. To identify an unknown microorganism, one that may not even use Earth-type biochemistry, requires a detection scheme which makes minimal assumptions and looks for the most general features. Recent work has demonstrated that the use of an array of electrochemical sensors which monitors the changes in a solution via electrical conductivity, pH, and ion selective electrodes, can be used to detect minute chemical perturbations caused by the growth of bacteria and

  5. Chemical Abundance Analysis of Moving Group W11450 (Latham 1)

    CERN Document Server

    O'Connell, Julia E; Frinchaboy, Peter M

    2016-01-01

    We present elemental abundances for all seven stars in Moving Group W11450 (Latham 1) to determine if they may be chemically related. These stars appear to be both spatially and kinematically related, but no spectroscopic abundance analysis exists in literature. Abundances for eight elements were derived via equivalent width analyses of high resolution (R $\\sim$60,000), high signal-to-noise ratio ($\\langle$SNR$\\rangle\\sim$100) spectra obtained with the Otto Struve 2.1m telescope and Sandiford Echelle Spectrograph at McDonald Observatory. The large star-to-star scatter in metallicity, -0.55 $\\leq$ [Fe/H] $\\leq$ 0.06 dex ($\\sigma$= 0.25), implies these stars were not produced from the same chemically homogeneous molecular cloud, and are therefore not part of a remnant or open cluster as previously proposed. Prior to this analysis, it was suggested that two stars in the group, W11449 & W11450, are possible wide binaries. The candidate wide binary pair show similar chemical abundance patterns with not only ir...

  6. Proximate analysis, backwards stepwise regression between gross calorific value, ultimate and chemical analysis of wood.

    Science.gov (United States)

    Telmo, C; Lousada, J; Moreira, N

    2010-06-01

    The gross calorific value (GCV), proximate, ultimate and chemical analysis of debark wood in Portugal were studied, for future utilization in wood pellets industry and the results compared with CEN/TS 14961. The relationship between GCV, ultimate and chemical analysis were determined by multiple regression stepwise backward. The treatment between hardwoods-softwoods did not result in significant statistical differences for proximate, ultimate and chemical analysis. Significant statistical differences were found in carbon for National (hardwoods-softwoods) and (National-tropical) hardwoods in volatile matter, fixed carbon, carbon and oxygen and also for chemical analysis in National (hardwoods-softwoods) for F and (National-tropical) hardwoods for Br. GCV was highly positively related to C (0.79 * * *) and negatively to O (-0.71 * * *). The final independent variables of the model were (C, O, S, Zn, Ni, Br) with R(2)=0.86; F=27.68 * * *. The hydrogen did not contribute statistically to the energy content.

  7. Microarray Technology for Major Chemical Contaminants Analysis in Food: Current Status and Prospects

    OpenAIRE

    Xiaoxia Ding; Wen Zhang; Xiaofeng Hu; Qi Zhang; Peiwu Li; Zhaowei Zhang

    2012-01-01

    Chemical contaminants in food have caused serious health issues in both humans and animals. Microarray technology is an advanced technique suitable for the analysis of chemical contaminates. In particular, immuno-microarray approach is one of the most promising methods for chemical contaminants analysis. The use of microarrays for the analysis of chemical contaminants is the subject of this review. Fabrication strategies and detection methods for chemical contaminants are discussed in detail....

  8. Chemical Bond Analysis of Single Crystal Growth of Magnesium Oxide

    Institute of Scientific and Technical Information of China (English)

    2006-01-01

    Starting from the crystallographic structure of magnesium oxide (MgO), both the chemical bond model of solids and Pauling's third rule (polyhedral sharing rule) were employed to quantitatively analyze the chemical bonding structure of constituent atoms and single crystal growth. Our analytical results show that MgO single crystals prefer to grow along the direction and the growth rate of the {100} plane is the slowest one. Therefore, the results show that the {100} plane of MgO crystals can be the ultimate morphology face, which is in a good agreement with our previous experimental results. The study indicate that the structure analysis is an effective tool to control the single-crystal growth.

  9. Analysis of chemical composition of high viscous oils

    Directory of Open Access Journals (Sweden)

    Irina Germanovna Yashchenko

    2014-07-01

    Full Text Available The spatial distribution of viscous oils which are considered as an important reserve for oil-production in future were studied on base of information from global database on oil physical and chemical properties. Changes in chemical composition of viscous oils in different basins and continents were analyzed as well. It is shown, on average, viscous oils are sulfur-bearing, low paraffin, highly resinous oils with an average content of asphaltenes and low content of the fraction boiling at 200 C. Study results of viscous oils peculiarities of Canada, Russia and Venezuela are given. The analysis results can be used to determine the optimal layouts and conditions of oil transportation, to improve the search methods of geochemical exploration, and to solve other problems in the oil chemistry.

  10. QUALITY ASSURANCE GUIDELINES FOR LABORATORIES PERFORMING FORENSIC ANALYSIS OF CHEMICAL TERRORISM

    Science.gov (United States)

    The Scientific Working Group on Forensic Analysis of Chemical Terrorism (SWGFACT) has developed the following quality assurance guidelines to provide laboratories engaged in forensic analysis of chemical evidence associated with terrorism a framework to implement a quality assura...

  11. Probabilistic Approach to Risk Analysis of Chemical Spills at Sea

    Institute of Scientific and Technical Information of China (English)

    Magda Bogalecka; Krzysztof Kolowrocki

    2006-01-01

    Risk analysis of chemical spills at sea and their consequences for sea environment are discussed. Mutual interactions between the process of the sea accident initiating events, the process of the sea environment threats, and the process of the sea environment degradation are investigated. To describe these three particular processes, the separate semi-Markov models are built. Furthermore, these models are jointed into one general model of these processes interactions.Moreover, some comments on the method for statistical identification of the considered models are proposed.

  12. Physcio chemical analysis of browning inhibitors treated solanum turberosum powder

    International Nuclear Information System (INIS)

    White potatoes (Solanum turberosum) were procured from agriculture Research Institute Tarnab Farm Peshawar to use for the preparation of potato powder. The process involves sorting. Washing, peeling slicing, blanching, treating with poly phenol oxidase inhibitors, dehydration, grinding and packing. All these parameters used in process were standardized. Chemical analysis of fresh potato and potato powder were carried out. Microbiological examination, functional properties and storage life studies of the potato powder were also performed. The product prepared by drying in cabinet dryer at 55 C for 7 hours was off white colour potatoes chips which was grinded to make off white potato powder. The potato powder possessed taste and texture. (author)

  13. Crystal-Chemical Analysis of Soil at Rocknest, Gale Crater

    Science.gov (United States)

    Morrison, S. M.; Downs, R. T.; Blake, D. F.; Bish, D. L.; Ming, D. W.; Morris, R. V.; Yen, A. S.; Chipera, S. J.; Treiman, A. H.; Vaniman, D. T.; Gellert, R.; Achilles, C. N.; Rampe, E. B.; Bristow, T. F.; Crisp, J. A.; Sarrazin, P. C.; DesMarais, D. J.; Morookian, J. M.; Anderson, R. C.

    2013-01-01

    The CheMin instrument on the Mars Science Laboratory rover Curiosity performed X-ray diffraction analysis on Martian soil [1] at Rocknest in Gale Crater. In particular, crystalline phases from scoop 5 were identified and analyzed with the Rietveld method [2]. Refined unit-cell parameters are reported in Table 1. Comparing these unit-cell parameters with those in the literature provides an estimate of the chemical composition of the crystalline phases. For instance, Fig. 1 shows the Mg-content of Fa-Fo olivine as a function of the b unit-cell parameter using literature data. Our refined b parameter is indicated by the black triangle.

  14. Microbiological and chemical analysis of land snails commercialised in Sicily

    Directory of Open Access Journals (Sweden)

    Antonello Cicero

    2015-05-01

    Full Text Available In this study 160 samples of snails belonging to the species Helix aspersa maxima and Helix aspersa muller were examined for chemical and microbiological analysis. Samples came from Greece and Poland. Results showed mean concentration of cadmium (0.35±0.036 mg/kg and lead (0.05±0.013 mg/kg much higher than the limit of detection. Mercury levels in both species were not detected. Microbiological analysis revealed the absence of Salmonella spp. and Clostridium spp. in both examined species. E. coli and K. oxytoca were observed in Helix aspersa maxima and Helix aspersa muller. Furthermore, one case of fungi positivity in samples of Helix aspersa muller was found. The reported investigations highlight the need to create and adopt a reference legislation to protect the health of consumers.

  15. Statistical sampling and chemical analysis of complex weapon components

    International Nuclear Information System (INIS)

    One of the waste streams generated by nuclear weapon dismantlement programs will be component ''hardware'', including complex electronic assemblies such as: radars, arming/fusing/firing systems, power sources, and use-control and safety systems. Sandia National Laboratories (SNL) has been the design and development laboratory for many of these components and will be responsible for their ultimate disposition. This disposition, whether it be reuse, material recycle, or disposal, will require some level of material characterization and analysis. Previous efforts at developing a process for segregation and characterization of hazardous materials in weapon components have been documented. This paper describes the results of recent activities undertaken in support of the Weapon Hardware Inventory Reduction Effort (WHIRE) at Sandia National Laboratories. These activities have been directed principally towards: The development of a statistically sound sampling plan for chemical analysis of weapon component materials; the development of a non-destructive analytical screening method for determining the Toxicity Characteristic of excess weapon hardware

  16. Integrated polymer waveguides for absorbance detection in chemical analysis systems

    DEFF Research Database (Denmark)

    Mogensen, Klaus Bo; El-Ali, Jamil; Wolff, Anders;

    2003-01-01

    A chemical analysis system for absorbance detection with integrated polymer waveguides is reported for the first time. The fabrication procedure relies on structuring of a single layer of the photoresist SU-8, so both the microfluidic channel network and the optical components, which include plan...... of the dye Bromothymol Blue. The influence of three different bonding procedures on the spectrally resolved propagation loss of the integrated waveguides between 500 nm and 900 nm was furthermore determined.......A chemical analysis system for absorbance detection with integrated polymer waveguides is reported for the first time. The fabrication procedure relies on structuring of a single layer of the photoresist SU-8, so both the microfluidic channel network and the optical components, which include planar...... waveguides and fiber-to-waveguide coupler structures, are defined in the same processing step. This results in self-alignment of all components and enables a fabrication and packaging time of only one day. The fabrication scheme has recently been presented elsewhere for fluorescence excitation of beads...

  17. Chemical Analysis of Wastewater from Unconventional Drilling Operations

    Directory of Open Access Journals (Sweden)

    Jonathan B. Thacker

    2015-04-01

    Full Text Available Trillions of liters of wastewater from oil and gas extraction are generated annually in the US. The contribution from unconventional drilling operations (UDO, such as hydraulic fracturing, to this volume will likely continue to increase in the foreseeable future. The chemical content of wastewater from UDO varies with region, operator, and elapsed time after production begins. Detailed chemical analyses may be used to determine its content, select appropriate treatment options, and identify its source in cases of environmental contamination. In this study, one wastewater sample each from direct effluent, a disposal well, and a waste pit, all in West Texas, were analyzed by gas chromatography-mass spectrometry, inductively coupled plasma-optical emission spectroscopy, high performance liquid chromatography-high resolution mass spectrometry, high performance ion chromatography, total organic carbon/total nitrogen analysis, and pH and conductivity analysis. Several compounds known to compose hydraulic fracturing fluid were detected among two of the wastewater samples including 2-butoxyethanol, alkyl amines, and cocamide diethanolamines, toluene, and o-xylene. Due both to its quantity and quality, proper management of wastewater from UDO will be essential.

  18. Cosmetics chemical composition characterization by instrumental neutron activation analysis

    International Nuclear Information System (INIS)

    Brazil is in the third position in the world's cosmetics market. It is an expanding and growing market where new products and manufacturing processes are in a constant and steady expansion. Therefore, it is mandatory that the composition of the products is well known in order to guarantee safety and quality of daily used cosmetics. The Brazilian National Health Surveillance Agency (ANVISA) has issued a resolution, RDC No. 48, March 16, 2006, which defines a 'List of Substances which can not be used in personal hygiene products, cosmetics and perfumes'. In this work, samples of locally manufactured and imported cosmetics (lipsticks, eye shadows, etc.) were analyzed using the Instrumental Neutron Activation Analysis technique. The samples were irradiated in the TRIGA IPR-R1 reactor of the Centro de Desenvolvimento da Tecnologia Nuclear (CDTN/CNEN), on a 100kW thermal power, with a thermal neutron fluence rate about 8x1011ncm-2s-1. The analysis has detected the chemical elements Br, Ba, Ga, Na, K, Sc, Fe, Cr, Zn, Sm, W, La, Rb, Cs, Ta, Ge, Co, U, Ti, V, Cl, Al, Mn and Cu. The concentrations of these elements are on a range from 5 to 3000μg.g-1. Some chemical elements observed in samples (Cl, Br, Cr, U) are included at ANVISA prohibitive list. (author)

  19. CHEMICALS

    CERN Multimedia

    Medical Service

    2002-01-01

    It is reminded that all persons who use chemicals must inform CERN's Chemistry Service (TIS-GS-GC) and the CERN Medical Service (TIS-ME). Information concerning their toxicity or other hazards as well as the necessary individual and collective protection measures will be provided by these two services. Users must be in possession of a material safety data sheet (MSDS) for each chemical used. These can be obtained by one of several means : the manufacturer of the chemical (legally obliged to supply an MSDS for each chemical delivered) ; CERN's Chemistry Service of the General Safety Group of TIS ; for chemicals and gases available in the CERN Stores the MSDS has been made available via EDH either in pdf format or else via a link to the supplier's web site. Training courses in chemical safety are available for registration via HR-TD. CERN Medical Service : TIS-ME :73186 or service.medical@cern.ch Chemistry Service : TIS-GS-GC : 78546

  20. Uranium complexes with macrosyclic polyethers. Synthesis and structural chemical analysis

    International Nuclear Information System (INIS)

    This dissertation reports about studies on the chemical coordination behaviour of uranium of oxidation stages IV and VI with regard to twelve different macrocyclic ligands. For the preparation of the complexes, for every system a different method has been developed. The elementary analysis of the various complexes including the uranium had been done by X-ray fluorescence analysis, and the structural characterization proceeded via vibrational, uv-vis and emission spectroscopy as well as 1H-NMR and 13C-spin-lattice relaxation time studies. Conformational analysis of the polyethers used allowed the structural changes in the complexes to be observed. The structural analysis of the hydrous uranium VI crown ether complexes yielded information of characteristic features of these types of complexes. The first coordination sphere of the uranyl ion with covalently bonded anion remains unchanged. As to the water content, there is a certain range. Depending upon the solvent used, the complexes have two or four H2O molecules per formula unit. (orig./EF)

  1. ANALYSIS OF THERMAL-CHEMICAL CHARACTERISTICS OF BIOMASS ENERGY PELLETS

    Directory of Open Access Journals (Sweden)

    Zorica Gluvakov

    2014-09-01

    Full Text Available In modern life conditions, when emphasis is on environmental protection and sustainable development, fuels produced from biomass are increasingly gaining in importance, and it is necessary to consider the quality of end products obtained from biomass. Based on the existing European standards, collected literature and existing laboratory methods, this paper presents results of testing individual thermal - chemical properties of biomass energy pellets after extrusion and cooling the compressed material. Analysing samples based on standard methods, data were obtained on the basis of which individual thermal-chemical properties of pellets were estimated. Comparing the obtained results with the standards and literature sources, it can be said that moisture content, ash content and calorific values are the most important parameters for quality analysis which decide on applicability and use-value of biomass energy pellets, as biofuel. This paper also shows the impact of biofuels on the quality of environmental protection. The conclusion provides a clear statement of quality of biomass energy pellets.

  2. Structural Analysis Of Alfa Fibers After Chemical Treatment

    Directory of Open Access Journals (Sweden)

    Zakaria Mouallif

    2015-02-01

    Full Text Available Nowadays, natural fibers are used as reinforcement in composite materials. The Alfa fibers have undergone an alkaline treatment with sodium hydroxide NaOH at a concentration of 10%, during an immersion period of two days. After drying, the Fourier transform infrared spectroscopy by attenuated total reflection (FTIR-ATR and X-ray diffraction (XRD were used for the analysis of the chemical properties of these fibers which were extracted from the plant Alfa of the region Al Haouz (Morocco in order to study the modifications resulting from the alkaline treatment. The results proved the presence of the cellulose, with an increase in its proportion in those fibers which have undergone an alkaline treatment with NaOH, the presence of lignin and pectin, as well as their disappearance after the alkaline extraction.

  3. Chemical gas analyzers for proximate analysis of mine atmosphere

    Energy Technology Data Exchange (ETDEWEB)

    Pochenkova, T.K.; Klassovskaya, N.A.; Zlenko, A.G.; Gus' kova, A.N. (Vsesoyuznyi Nauchno-Issledovatel' skii Institut Gornogo Dela, Donetsk (Ukraine))

    1992-09-01

    Describes a series of chemical gas analyzers developed by the VNIIGD institute for proximate analysis of mine atmosphere in coal mines. The new GKh-4, GKh-5, GKh-6, GKh CO-5 use detector tubes for carbon monoxide and dioxide, nitrogen oxides, sulfur dioxide, oxygen and hydrogen sulfide. These devices allow miners to determine gas concentrations in the mine atmosphere in less than 4 minutes with an accuracy of +/-25%. The series is now complemented by the GKh-M CH[sub 2]O-0.004 gas analyzer for measuring formaldehyde content in mine air during mine rescue operations conducted with the use of carbamide-formaldehyde resins. Key technical data on the gas analyzers are given.

  4. Chemical analysis of ancient relicts in the Milky Way disk

    Directory of Open Access Journals (Sweden)

    Tautvaišienė G.

    2012-02-01

    Full Text Available We present detailed analysis of two groups of F- and G- type stars originally found to have similarities in their orbital parameters. The distinct kinematic properties suggest that they might originate from ancient accretion events in the Milky Way. From high resolution spectra taken with the spectrograph FIES at the Nordic Optical Telescope, La Palma, we determined abundances of oxygen, alpha- and r-process elements. Our results indicate that the sample of investigated stars is chemically homogeneous and the abundances of oxygen, alpha and r-process elements are overabundant in comparison with Galactic disk dwarfs. This provides the additional evidence that those stellar groups had the common formation and possible origin from disrupted satellites.

  5. Comparison of descriptive sensory analysis and chemical analysis for oxidative changes in milk

    DEFF Research Database (Denmark)

    Hedegaard, R V; Kristensen, D; Nielsen, Jacob Holm;

    2006-01-01

    and lipolytic changes occurring in the milk during chill storage for 4 d. Sensory analysis and chemical analysis showed high correlation between the typical descriptors for oxidation such as cardboard, metallic taste, and boiled milk and specific chemical markers for oxidation such as hexanal. Notably, primary......Oxidation in 3 types of bovine milk with different fatty acid profiles obtained through manipulation of feed was evaluated by analytical methods quantifying the content of potential antioxidants, the tendency of formation of free radicals, and the accumulation of primary and secondary oxidation...

  6. Microarray Technology for Major Chemical Contaminants Analysis in Food: Current Status and Prospects

    Directory of Open Access Journals (Sweden)

    Xiaoxia Ding

    2012-07-01

    Full Text Available Chemical contaminants in food have caused serious health issues in both humans and animals. Microarray technology is an advanced technique suitable for the analysis of chemical contaminates. In particular, immuno-microarray approach is one of the most promising methods for chemical contaminants analysis. The use of microarrays for the analysis of chemical contaminants is the subject of this review. Fabrication strategies and detection methods for chemical contaminants are discussed in detail. Application to the analysis of mycotoxins, biotoxins, pesticide residues, and pharmaceutical residues is also described. Finally, future challenges and opportunities are discussed.

  7. Chemical hazards analysis of resilient flooring for healthcare.

    Science.gov (United States)

    Lent, Tom; Silas, Julie; Vallette, Jim

    2010-01-01

    This article addresses resilient flooring, evaluating the potential health effects of vinyl flooring and the leading alternatives-synthetic rubber, polyolefin, and linoleum-currently used in the healthcare marketplace. The study inventories chemicals incorporated as components of each of the four material types or involved in their life cycle as feedstocks, intermediary chemicals, or emissions. It then characterizes those chemicals using a chemical hazard-based framework that addresses persistence and bioaccumulation, human toxicity, and human exposures. PMID:21165873

  8. Chemical analysis of Argonne premium coal samples. Bulletin

    Energy Technology Data Exchange (ETDEWEB)

    Palmer, C.A.

    1997-11-01

    Contents: The Chemical Analysis of Argonne Premium Coal Samples: An Introduction; Rehydration of Desiccated Argonne Premium Coal Samples; Determination of 62 Elements in 8 Argonne Premium Coal Ash Samples by Automated Semiquantitative Direct-Current Arc Atomic Emission Spectrography; Determination of 18 Elements in 5 Whole Argonne Premium Coal Samples by Quantitative Direct-Current Arc Atomic Emission Spectrography; Determination of Major and Trace Elements in Eight Argonne Premium Coal Samples (Ash and Whole Coal) by X-Ray Fluorescence Spectrometry; Determination of 29 Elements in 8 Argonne Premium Coal Samples by Instrumental Neutron Activation Analysis; Determination of Selected Elements in Coal Ash from Eight Argonne Premium Coal Samples by Atomic Absorption Spectrometry and Atomic Emission Spectrometry; Determination of 25 Elements in Coal Ash from 8 Argonne Premium Coal Samples by Inductively Coupled Argon Plasma-Atomic Emission Spectrometry; Determination of 33 Elements in Coal Ash from 8 Argonne Premium Coal Samples by Inductively Coupled Argon Plasma-Mass Spectrometry; Determination of Mercury and Selenium in Eight Argonne Premium Coal Samples by Cold-Vapor and Hydride-Generation Atomic Absorption Spectrometry; Determinaton of Carbon, Hydrogen, and Nitrogen in Eight Argonne Premium Coal Samples by Using a Gas Chromatographic Analyzer with a Thermal Conductivity Detector; and Compilation of Multitechnique Determinations of 51 Elements in 8 Argonne Premium Coal Samples.

  9. Chemical analysis and potential health risks of hookah charcoal.

    Science.gov (United States)

    Elsayed, Yehya; Dalibalta, Sarah; Abu-Farha, Nedal

    2016-11-01

    Hookah (waterpipe) smoking is a very common practice that has spread globally. There is growing evidence on the hazardous consequences of smoking hookah, with studies indicating that its harmful effects are comparable to cigarette smoking if not worse. Charcoal is commonly used as a heating source for hookah smoke. Although charcoal briquettes are thought to be one of the major contributors to toxicity, their composition and impact on the smoke generated remains largely unidentified. This study aims to analyze the elemental composition of five different raw synthetic and natural charcoals by using Carbon-Hydrogen-Nitrogen (CHN) analysis, inductively coupled plasma (ICP), and scanning electron microscopy coupled with energy dispersive X-Ray spectrometry (SEM-EDS). Elemental analysis showed that the raw charcoals contain heavy metals such as zinc, iron, cadmium, vanadium, aluminum, lead, chromium, manganese and cobalt at concentrations similar, if not higher than, cigarettes. In addition, thermal desorption-gas chromatography-mass spectrometry (TD-GC-MS) was used to analyze the chemical composition of the smoke produced from burning the charcoal samples. The smoke emitted from charcoal was found to be the source of numerous compounds which could be hazardous to health. A total of seven carcinogens, 39 central nervous system depressants and 31 respiratory irritants were identified. PMID:27343945

  10. Safety- and Risk Analysis Activities in Chemical Industry in Europe

    Energy Technology Data Exchange (ETDEWEB)

    Kozine, Igor; Duijm, Nijs Jan; Lauridsen Kurt [Risoe National Laboratory, Roskilde (Denmark). Systems Analysis Department

    2001-07-01

    The current paper gives an overview of the legislation and the methods used in safety and risk management in the chemical industry within Europe and in particular within the European Union. The paper is based on a report that has been written for the SOS-1 project under the Nordic nuclear safety research (NKS). Safety- and risk-related matters in the process industry, in particular, in chemical, within the EU are subject to consideration at three levels: (1) EU legislation, (2) European/intemational standardisation, and (3) socio-economic analysis. EC Directives define the 'essential requirements', e.g., protection of health and safety, that must be fulfilled when goods are placed on the market or some industry is put into operation. The European standards bodies (CEN, CENELEC and ETSI) have the task of establishing the corresponding technical specifications, meeting the essential requirements of the Directives, compliance with which will provide a presumption of conformity with the essential requirements. Such specifications are referred to as 'harmonised standards'. Compliance with harmonised standards remains voluntary, and manufacturers are free to choose any other technical solution that provides compliance with the essential requirements. This view is stated in the 'New Approach' to technical harmonisation and standardisation (details can be found on the web page: http://europe.eu.int/comm/enterprise/newapproach/standardization/index .html). Standardisation as well as the regulation of technical risks is increasingly being undertaken at European or international level. The European legislator limits its role to the affirmation of overall objectives, and leaves it to the economic players to draw up the technical procedures and standards to specify in detail the ways and means of attaining them. Many countries have introduced requirements that new legislation and/or administrative regulations be subject to socio-economic analysis

  11. Meta-Analysis of the Chemical and Non-Chemical Stressors Affecting Childhood Obesity

    Science.gov (United States)

    Worldwide, approximately 42 million children under the age of 5 years are considered overweight or obese. While much research has focused on individual behaviors impacting obesity, little research has emphasized the complex interactions of numerous chemical and non-chemical stres...

  12. ACTINIDE REMOVAL PROCESS SAMPLE ANALYSIS, CHEMICAL MODELING, AND FILTRATION EVALUATION

    Energy Technology Data Exchange (ETDEWEB)

    Martino, C.; Herman, D.; Pike, J.; Peters, T.

    2014-06-05

    Filtration within the Actinide Removal Process (ARP) currently limits the throughput in interim salt processing at the Savannah River Site. In this process, batches of salt solution with Monosodium Titanate (MST) sorbent are concentrated by crossflow filtration. The filtrate is subsequently processed to remove cesium in the Modular Caustic Side Solvent Extraction Unit (MCU) followed by disposal in saltstone grout. The concentrated MST slurry is washed and sent to the Defense Waste Processing Facility (DWPF) for vitrification. During recent ARP processing, there has been a degradation of filter performance manifested as the inability to maintain high filtrate flux throughout a multi-batch cycle. The objectives of this effort were to characterize the feed streams, to determine if solids (in addition to MST) are precipitating and causing the degraded performance of the filters, and to assess the particle size and rheological data to address potential filtration impacts. Equilibrium modelling with OLI Analyzer{sup TM} and OLI ESP{sup TM} was performed to determine chemical components at risk of precipitation and to simulate the ARP process. The performance of ARP filtration was evaluated to review potential causes of the observed filter behavior. Task activities for this study included extensive physical and chemical analysis of samples from the Late Wash Pump Tank (LWPT) and the Late Wash Hold Tank (LWHT) within ARP as well as samples of the tank farm feed from Tank 49H. The samples from the LWPT and LWHT were obtained from several stages of processing of Salt Batch 6D, Cycle 6, Batch 16.

  13. Avogadro: an advanced semantic chemical editor, visualization, and analysis platform

    Directory of Open Access Journals (Sweden)

    Hanwell Marcus D

    2012-08-01

    Full Text Available Abstract Background The Avogadro project has developed an advanced molecule editor and visualizer designed for cross-platform use in computational chemistry, molecular modeling, bioinformatics, materials science, and related areas. It offers flexible, high quality rendering, and a powerful plugin architecture. Typical uses include building molecular structures, formatting input files, and analyzing output of a wide variety of computational chemistry packages. By using the CML file format as its native document type, Avogadro seeks to enhance the semantic accessibility of chemical data types. Results The work presented here details the Avogadro library, which is a framework providing a code library and application programming interface (API with three-dimensional visualization capabilities; and has direct applications to research and education in the fields of chemistry, physics, materials science, and biology. The Avogadro application provides a rich graphical interface using dynamically loaded plugins through the library itself. The application and library can each be extended by implementing a plugin module in C++ or Python to explore different visualization techniques, build/manipulate molecular structures, and interact with other programs. We describe some example extensions, one which uses a genetic algorithm to find stable crystal structures, and one which interfaces with the PackMol program to create packed, solvated structures for molecular dynamics simulations. The 1.0 release series of Avogadro is the main focus of the results discussed here. Conclusions Avogadro offers a semantic chemical builder and platform for visualization and analysis. For users, it offers an easy-to-use builder, integrated support for downloading from common databases such as PubChem and the Protein Data Bank, extracting chemical data from a wide variety of formats, including computational chemistry output, and native, semantic support for the CML file format

  14. A spectroscopic analysis of the chemically peculiar star HD207561

    CERN Document Server

    Joshi, S; Martinez, P; Sachkov, M; Joshi, Y C; Seetha, S; Chakradhari, N K; Mary, D L; Girish, V; Ashoka, B N

    2012-01-01

    In this paper we present a high-resolution spectroscopic analysis of the chemically peculiar star HD207561. During a survey programme to search for new roAp stars in the Northern hemisphere, Joshi et al. (2006) observed significant photometric variability on two consecutive nights in the year 2000. The amplitude spectra of the light curves obtained on these two nights showed oscillations with a frequency of 2.79 mHz [P~6-min]. However, subsequent follow-up observations could not confirm any rapid variability. In order to determine the spectroscopic nature of HD207561, high-resolution spectroscopic and spectro-polarimetric observations were carried out. A reasonable fit of the calculated Hbeta line profile to the observed one yields the effective temperature (Teff) and surface gravity (log g) as 7300 K and 3.7 dex, respectively. The derived projected rotational velocity (vsin i) for HD207561 is 74 km/sec indicative of a relatively fast rotator. The position of HD207561 in the H-R diagram implies that this is s...

  15. Microplasmas for chemical analysis: analytical tools or research toys?

    International Nuclear Information System (INIS)

    An overview of the activities of the research groups that have been involved in fabrication, development and characterization of microplasmas for chemical analysis over the last few years is presented. Microplasmas covered include: miniature inductively coupled plasmas (ICPs); capacitively coupled plasmas (CCPs); microwave-induced plasmas (MIPs); a dielectric barrier discharge (DBD); microhollow cathode discharge (MCHD) or microstructure electrode (MSE) discharges, other microglow discharges (such as those formed between 'liquid' electrodes); microplasmas formed in micrometer-diameter capillary tubes for gas chromatography (GC) or high-performance liquid chromatography (HPLC) applications, and a stabilized capacitive plasma (SCP) for GC applications. Sample introduction into microplasmas, in particular, into a microplasma device (MPD), battery operation of a MPD and of a mini- in-torch vaporization (ITV) microsample introduction system for MPDs, and questions of microplasma portability for use on site (e.g., in the field) are also briefly addressed using examples of current research. To emphasize the significance of sample introduction into microplasmas, some previously unpublished results from the author's laboratory have also been included. And an overall assessment of the state-of-the-art of analytical microplasma research is provided

  16. TECHNO-ECONOMIC ANALYSIS OF MODERNIZATION FOR CHEMICAL EQUIPMENT

    OpenAIRE

    Задольський, Аркадій Михайлович

    2015-01-01

    Industry of Ukraine is currently in a very difficult situation. This fully relates to the chemical industry. The real way to overcome negative developments, in the chemical industry, is improving its material base and objects of fixed assets. First of all, need improvement, machinery and equipment (chemical equipment). This important problem can be solved by upgrading existing equipment. In order to choose the most efficient option for replacement of obsolete equipment, should apply the techn...

  17. Similarity Analysis of Cable Insulations by Chemical Test

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Jong Seog [Central Research Institute of Korea Hydro and Nuclear Power Co., Daejeon (Korea, Republic of)

    2013-10-15

    As result of this experiment, it was found that FT-IR test for material composition, TGA test for aging trend are applicable for similarity analysis of cable materials. OIT is recommended as option if TGA doesn't show good trend. Qualification of new insulation by EQ report of old insulation should be based on higher activation energy of new insulation than that of old one in the consideration of conservatism. In old nuclear power plant, it is easy to find black cable which has no marking of cable information such as manufacturer, material name and voltage. If a type test is required for qualification of these cables, how could I select representative cable? How could I determine the similarity of these cables? If manufacturer has qualified a cable for nuclear power plant more than a decade ago and composition of cable material is changed with similar one, is it acceptable to use the old EQ report for recently manufactured cable? It is well known to use FT-IR method to determine the similarity of cable materials. Infrared ray is easy tool to compare compositions of each material. But, it is not proper to compare aging trend of these materials. Study for similarity analysis of cable insulation by chemical test is described herein. To study a similarity evaluation method for polymer materials, FT-IR, TGA and OIT tests were performed for two cable insulation(old and new) which were supplied from same manufacturer. FT-IR shows good result to compare material compositions while TGA and OIT show good result to compare aging character of materials.

  18. Nonradiological chemical pathway analysis and identification of chemicals of concern for environmental monitoring at the Hanford Site

    International Nuclear Information System (INIS)

    Pacific Northwest's Surface Environmental Surveillance Project (SESP) is an ongoing effort tot design, review, and conducted monitoring on and off the Hanford site. Chemicals of concern that were selected are listed. Using modeled exposure pathways, the offsite cancer incidence and hazard quotient were calculated and a retrospective pathway analysis performed to estimate what onsite concentrations would be required in the soil for each chemical of concern and other detected chemicals that would be required to obtain an estimated offsite human-health risk of 1.0E-06 cancer incidence or 1.0 hazard quotient. This analysis indicates that current nonradiological chemical contamination occurring on the site does not pose a significant offsite human-health risk; the highest cancer incidence to the offsite maximally exposed individual was from arsenic (1.76E-10); the highest hazard quotient was chromium(VI) (1.48E-04). The most sensitive pathways of exposure were surfacewater and aquatic food consumption. Combined total offsite excess cancer incidence was 2.09E-10 and estimated hazard quotient was 2.40E-04. Of the 17 identified chemicals of concern, the SESP does not currently (routinely) monitor arsenic, benzo(a)pyrene, bis(2- ethylhexyl)phthalate (BEHP), and chrysene. Only 3 of the chemicals of concern (arsenic, BEHP, chloroform) could actually occur in onsite soil at concern high enough to cause a 1.0E-06 excess cancer incidence or a 1.0 hazard index for a given offsite exposure pathway. During the retrospective analysis, 20 other chemicals were also evaluated; only vinyl chloride and thallium could reach targeted offsite risk values

  19. Spectroscopic and quantum chemical analysis of Isonicotinic acid methyl ester

    Science.gov (United States)

    Shoba, D.; Periandy, S.; Govindarajan, M.; Gayathri, P.

    2015-02-01

    In this present study, an organic compound Isonicotinic acid methyl ester (INAME) was structurally characterized by FTIR, FT-Raman, and NMR and UV spectroscopy. The optimized geometrical parameters and energies of all different and possible conformers of INAME are obtained from Density Functional Theory (DFT) by B3LYP/6-311++G(d,p) method. There are three conformers (SI, SII-1, and SII-2) for this molecule (ground state). The most stable conformer of INAME is SI conformer. The molecular geometry and vibrational frequencies of INAME in the ground state have been calculated by using HF and density functional method (B3LYP) 6-311++G (d,p) basis set. Detailed vibrational spectral analysis has been carried out and assignments of the observed fundamental bands have been proposed on the basis of peak positions and relative intensities. The computed vibrational frequencies were compared with the experimental frequencies, which yield good agreement between observed and calculated frequencies. A study on the electronic properties, such as HOMO and LUMO energies were performed by time independent DFT approach. Besides, molecular electrostatic potential (MEP) and thermodynamic properties were performed. The electric dipole moment (μ) and first hyper polarizability (β) values of the investigated molecule were computed using ab initio quantum mechanical calculations. The calculated results show that the INAME molecule may have microscopic nonlinear optical (NLO) behavior with non zero values. The 1H and 13C nuclear magnetic resonance (NMR) chemical shifts of the molecule were calculated by gauge independent atomic orbital (GIAO) method.

  20. Meta-Analysis of the Chemical and Non-Chemical Stressors Affecting Childhood Obesity?

    Science.gov (United States)

    Background: Worldwide, approximately 42 million children under the age of 5 years are considered overweight or obese. While much research has focused on individual behaviors impacting obesity, little research has emphasized the complex interactions of numerous chemical and non-ch...

  1. SOIL QUALITY ASSESSMENT BASED ON CHEMICAL, ENZYMATIC AND BACTERIOLOGICAL ANALYSIS

    Directory of Open Access Journals (Sweden)

    Sofia-Paulina BALAURE

    2012-01-01

    Full Text Available This study highlights the problem of soil pollution as the result of human activities. Soil pollutans may be either chemicals or biological in nature. microbial enzymatic activities are often proposed as indicators of environmental stress. The soil samples were submitted by chemical, microbiological and enzymatic analyses. Chemical analyses were been made for determinating the heavy metals. Heavy metals from the forest soil were represented by Cu, Zn, Mn, Ni, Pb, Cd and Cr. To evaluate the concentration in heavy metals from the filtrate, we used a acetylene-nitrous oxide flame atomic absorption spectrophotometry. Potential dehydrogenase activity, the only indicator of the possible sources of pollution, excluded the presence of either chemical or biological pollution. The number of bacteria involved in the biogeochemical cycle of nitrogen in the analyzed soil indicated a high efficiency regarding the mineralization of the organic residues of plant and animal origin.

  2. Disclosure of hydraulic fracturing fluid chemical additives: analysis of regulations.

    Science.gov (United States)

    Maule, Alexis L; Makey, Colleen M; Benson, Eugene B; Burrows, Isaac J; Scammell, Madeleine K

    2013-01-01

    Hydraulic fracturing is used to extract natural gas from shale formations. The process involves injecting into the ground fracturing fluids that contain thousands of gallons of chemical additives. Companies are not mandated by federal regulations to disclose the identities or quantities of chemicals used during hydraulic fracturing operations on private or public lands. States have begun to regulate hydraulic fracturing fluids by mandating chemical disclosure. These laws have shortcomings including nondisclosure of proprietary or "trade secret" mixtures, insufficient penalties for reporting inaccurate or incomplete information, and timelines that allow for after-the-fact reporting. These limitations leave lawmakers, regulators, public safety officers, and the public uninformed and ill-prepared to anticipate and respond to possible environmental and human health hazards associated with hydraulic fracturing fluids. We explore hydraulic fracturing exemptions from federal regulations, as well as current and future efforts to mandate chemical disclosure at the federal and state level.

  3. 40 CFR 761.292 - Chemical extraction and analysis of individual samples and composite samples.

    Science.gov (United States)

    2010-07-01

    ....61(a)(6) § 761.292 Chemical extraction and analysis of individual samples and composite samples. Use... 40 Protection of Environment 30 2010-07-01 2010-07-01 false Chemical extraction and analysis of individual samples and composite samples. 761.292 Section 761.292 Protection of Environment...

  4. CERENA: ChEmical REaction Network Analyzer--A Toolbox for the Simulation and Analysis of Stochastic Chemical Kinetics.

    Science.gov (United States)

    Kazeroonian, Atefeh; Fröhlich, Fabian; Raue, Andreas; Theis, Fabian J; Hasenauer, Jan

    2016-01-01

    Gene expression, signal transduction and many other cellular processes are subject to stochastic fluctuations. The analysis of these stochastic chemical kinetics is important for understanding cell-to-cell variability and its functional implications, but it is also challenging. A multitude of exact and approximate descriptions of stochastic chemical kinetics have been developed, however, tools to automatically generate the descriptions and compare their accuracy and computational efficiency are missing. In this manuscript we introduced CERENA, a toolbox for the analysis of stochastic chemical kinetics using Approximations of the Chemical Master Equation solution statistics. CERENA implements stochastic simulation algorithms and the finite state projection for microscopic descriptions of processes, the system size expansion and moment equations for meso- and macroscopic descriptions, as well as the novel conditional moment equations for a hybrid description. This unique collection of descriptions in a single toolbox facilitates the selection of appropriate modeling approaches. Unlike other software packages, the implementation of CERENA is completely general and allows, e.g., for time-dependent propensities and non-mass action kinetics. By providing SBML import, symbolic model generation and simulation using MEX-files, CERENA is user-friendly and computationally efficient. The availability of forward and adjoint sensitivity analyses allows for further studies such as parameter estimation and uncertainty analysis. The MATLAB code implementing CERENA is freely available from http://cerenadevelopers.github.io/CERENA/.

  5. Ultrastructural Analysis of Urinary Stones by Microfocus Computed Tomography and Comparison with Chemical Analysis

    Directory of Open Access Journals (Sweden)

    Tolga Karakan

    2016-06-01

    Full Text Available Objective: To investigate the ultra-structure of urinary system stones using micro-focus computed tomography (MCT, which makes non-destructive analysis and to compare with wet chemical analysis. Methods: This study was carried out at the Ankara Train­ing and Research hospital. Renal stones, removed from 30 patients during percutaneous nephrolithotomy (PNL surgery, were included in the study. The stones were blindly evaluated by the specialists with MCT and chemi­cal analysis. Results: The comparison of the stone components be­tween chemical analysis and MCT, showed that the rate of consistence was very low (p0.05. It was also seen that there was no significant relation between its 3D structure being heterogeneous or homogenous. Conclusion: The stone analysis with MCT is a time con­suming and costly method. This method is useful to un­derstand the mechanisms of stone formation and an im­portant guide to develop the future treatment modalities.

  6. Chemical Analysis of Wastewater from Unconventional Drilling Operations

    OpenAIRE

    Jonathan B. Thacker; Doug D. Carlton; Zacariah L. Hildenbrand; Kadjo, Akinde F.; Schug, Kevin A.

    2015-01-01

    Trillions of liters of wastewater from oil and gas extraction are generated annually in the US. The contribution from unconventional drilling operations (UDO), such as hydraulic fracturing, to this volume will likely continue to increase in the foreseeable future. The chemical content of wastewater from UDO varies with region, operator, and elapsed time after production begins. Detailed chemical analyses may be used to determine its content, select appropriate treatment options, and identify ...

  7. China Rubber Chemicals Production and Market Situation Analysis

    Institute of Scientific and Technical Information of China (English)

    Liang Cheng

    2011-01-01

    Because the stimulus driven impact of the rapid growth of tire and other rubber products' output,in recent years,the production and marketing of domestic rubber chemicals appear to increase,and the specific production and marketing conditions are as follows: 1.Rapid Growth of Chemicals Output From 2009 to 2010,in China an upsurge of expanding or building new rubber chemicals equipment was raised.These equipment were planned to be put into production in 2010 with newly increased production capacity of about 120,000 tons,among which there were 40,000 tons antioxidant 4020,50,000tons accelerator M,and about 40,000 tons other Chemicals.In 2010,the total output was 701,000 tons,with year-on-year growth of 17.8% or so.In 2010,the total sales volume of domestic rubber chemicals were 13 billion yuan,and the export volume was about 180,000 tons,basically the same with that in 2009.See the statistics of domestic rubber chemicals output from 2009 to 2010 in Table 1.

  8. Evaluating Chemical Persistence in a Multimedia Environment: ACART Analysis

    Energy Technology Data Exchange (ETDEWEB)

    Bennett, D.H.; McKone, T.E.; Kastenberg, W.E.

    1999-02-01

    For the thousands of chemicals continuously released into the environment, it is desirable to make prospective assessments of those likely to be persistent. Persistent chemicals are difficult to remove if adverse health or ecological effects are later discovered. A tiered approach using a classification scheme and a multimedia model for determining persistence is presented. Using specific criteria for persistence, a classification tree is developed to classify a chemical as ''persistent'' or ''non-persistent'' based on the chemical properties. In this approach, the classification is derived from the results of a standardized unit world multimedia model. Thus, the classifications are more robust for multimedia pollutants than classifications using a single medium half-life. The method can be readily implemented and provides insight without requiring extensive and often unavailable data. This method can be used to classify chemicals when only a few properties are known and be used to direct further data collection. Case studies are presented to demonstrate the advantages of the approach.

  9. International Research Project on the Effects of Chemical Ageing of Polymers on Performance Properties: Chemical and Thermal Analysis

    Science.gov (United States)

    Bulluck, J. W.; Rushing, R. A.

    1996-01-01

    Work during the past six months has included significant research in several areas aimed at further clarification of the aging and chemical failure mechanism of thermoplastics (PVDF or Tefzel) pipes. Among the areas investigated were the crystallinity changes associated with both the Coflon and Tefzel after various simulated environmental exposures using X-ray diffraction analysis. We have found that significant changes in polymer crystallinity levels occur as a function of the exposures. These crystallinity changes may have important consequences on the fracture, fatigue, tensile, and chemical resistance of the materials. We have also noted small changes in the molecular weight distribution. Again these changes may result in variations in the mechanical and chemical properties in the material. We conducted numerous analytical studies with methods including X-ray Diffraction, Gel Permeation Chromatography, Fourier Transform Infrared Spectroscopy, Ultra- Violet Scanning Analysis, GC/Mass Spectrometry, Differential Scanning Calorimetry and Thermomechanical Analysis. In the ultra-violet analysis we noted the presence of an absorption band indicative of triene formation. We investigated a number of aged samples of both Tefzel and Coflon that were forwarded from MERL. We also cast films at SWT and subjected these films to a refluxing methanol 1% ethylene diamine solution. An updated literature search was conducted using Dialog and DROLLS to identify any new papers that may have been published in the open literature since the start of this project. The updated literature search and abstracts are contained in the Appendix section of this report.

  10. Analysis of forward and inverse problems in chemical dynamics and spectroscopy

    Energy Technology Data Exchange (ETDEWEB)

    Rabitz, H. [Princeton Univ., NJ (United States)

    1993-12-01

    The overall scope of this research concerns the development and application of forward and inverse analysis tools for problems in chemical dynamics and chemical kinetics. The chemical dynamics work is specifically associated with relating features in potential surfaces and resultant dynamical behavior. The analogous inverse research aims to provide stable algorithms for extracting potential surfaces from laboratory data. In the case of chemical kinetics, the focus is on the development of systematic means to reduce the complexity of chemical kinetic models. Recent progress in these directions is summarized below.

  11. ANALYSIS OF SOLUBLE CHEMICAL TRANSFER BY RUNOFF WATER IN FIELD

    Institute of Scientific and Technical Information of China (English)

    TONG Ju-xiu; YANG Jin-zhong

    2008-01-01

    In order to determine the main factors influencing soluble chemical transfer and corresponding techniques for reducing fertilizer loss caused by runoff in irrigated fields, a physically based two-layer model was developed with incomplete mixing theory. Different forms of incomplete mixing parameters were introduced in the model, which was successfully verified with previous published experimental data. According to comparison, the chemicals loss of fertilizer is very sensitive to the runoff-related parameter while it is not sensitive to the infiltration-related parameter. The calculated results show that the chemicals in infiltration water play an important role in the early time of rainfall even with saturated soil, and it is mainly in the runoff flow in the late rainfall. Therefore, prevention of shallow subsurface drainage in the early rainfall is an effective way to reduce fertilizer loss, and the coverage on soil surface is another effective way.

  12. Powerful chemical technique. [CSIR uses new x-ray diffractometer for structural chemical analysis

    Energy Technology Data Exchange (ETDEWEB)

    The CSIR's National Chemical Research Laboratory (NCRL) is now using one of the most powerful techniques available to determine the structure of molecules. It has recently acquired a Single Crystal X-ray Diffractometer. This powerful method provides the only means of determining the structure of certain compounds. NCRL scientists often carry out structure determinations to find out the relative or absolute stereochemistry of molecules. This is important when correlating physiological activity and structure, information which is necessary for synthesizing medicines with specific characteristics.

  13. Mass spectrometry analysis of polychlorinated biphenyls: chemical ionization and selected ion chemical ionization using methane as a reagent gas

    OpenAIRE

    RAYMOND E. MARCH; MILA D. LAUSEVIC; TATJANA M. VASILJEVIC

    2000-01-01

    In the present paper a quadrupole ion trap mass spectrometer, coupled with a gas chromatograph, was used to compare the electron impact ionization (EI) and chemical ionization (Cl) technique, in terms of their selectivity in polychlorinated biphenyls (PCBs) quantitative analysis. The experiments were carried out with a modified Varian SATURN III quadrupole ion-storage mass spectrometer equipped with Varian waveform generator, coupled with a gas chromatograph with DB-5 capillary column. The di...

  14. Probabilistic thermo-chemical analysis of a pultruded composite rod

    NARCIS (Netherlands)

    Baran, Ismet; Tutum, Cem C.; Hattel, Jesper H.

    2012-01-01

    In the present study the deterministic thermo-chemical pultrusion simulation of a composite rod taken from the literature [7] is used as a validation case. The predicted centerline temperature and cure degree profiles of the rod match well with those in the literature [7]. Following the validation c

  15. Analysis of chemical coal cleaning processes. Final report

    Energy Technology Data Exchange (ETDEWEB)

    1980-06-01

    Six chemical coal cleaning processes were examined. Conceptual designs and costs were prepared for these processes and coal preparation facilities, including physical cleaning and size reduction. Transportation of fine coal in agglomerated and unagglomerated forms was also discussed. Chemical cleaning processes were: Pittsburgh Energy Technology Center, Ledgemont, Ames Laboratory, Jet Propulsion Laboratory (two versions), and Guth Process (KVB). Three of the chemical cleaning processes are similar in concept: PETC, Ledgemont, and Ames. Each of these is based on the reaction of sulfur with pressurized oxygen, with the controlling factor being the partial pressure of oxygen in the reactor. All of the processes appear technically feasible. Economic feasibility is less certain. The recovery of process chemicals is vital to the JPL and Guth processes. All of the processes consume significant amounts of energy in the form of electric power and coal. Energy recovery and increased efficiency are potential areas for study in future more detailed designs. The Guth process (formally designed KVB) appears to be the simplest of the systems evaluated. All of the processes require future engineering to better determine methods for scaling laboratory designs/results to commercial-scale operations. A major area for future engineering is to resolve problems related to handling, feeding, and flow control of the fine and often hot coal.

  16. Portfolio Assessment on Chemical Reactor Analysis and Process Design Courses

    Science.gov (United States)

    Alha, Katariina

    2004-01-01

    Assessment determines what students regard as important: if a teacher wants to change students' learning, he/she should change the methods of assessment. This article describes the use of portfolio assessment on five courses dealing with chemical reactor and process design during the years 1999-2001. Although the use of portfolio was a new…

  17. CHEMICAL ANALYSIS OF DENSE-GAS EXTRACTS FROM LIME FLOWERS

    Directory of Open Access Journals (Sweden)

    Demyanenko DV

    2015-04-01

    Full Text Available The purpose of this work was to make qualitative and quantitative analysis of phenolic biologically active substances (BAS in the extracts produced from lime flowers with condensed gases, using method of high-performance liquid chromatography (HPLC. Materials and methods: materials for this study were the extracts obtained by consequent processing of the herbal drug and marcs thereof with various condensed gases: difluorochloromethane (Freon R22, difluoromethane (Freon R32, azeotropic mixture of difluoromethane with pentafluoroethane (Freon 410A and freon-ammonium mixture. Extracts obtained with the latter were subjected to further fractionation by liquidliquid separation into hexane, chloroform, ethyl acetate and aqueous-alcohol phases. Besides, the supercritical СО2 extract, obtained from the herbal drug under rather strong conditions (at temperature 60°С and pressure 400 bar, was studied in our previous research. Presence of phenolic BAS and their quantity in the researched samples were determined by method of HPLC with UVspectrometric detection. Results and discussion: It has been found that Freon R22 extracted trace amounts of rutin from lime flowers – its content was only 0.08% of the total extract weight. On the other hand, Freons R32 and R410А showed good selectivity to moderately polar BAS of lime flowers (derivatives of flavonoids and hydroxycinnamic acids: in particular, the extract obtained with freon R32 contained about 1.3% of the total phenolic substances, and it was the only one of the investigated condensed gases used by us which took the basic flavonoid of lime flowers tiliroside – its content was 0.42% of extract weight. Also Freons R32 and R410А were able to withdraw another compound dominating among phenolic substances in the yielded extracts. Its quantity was rather noticeable – up to 0.87% of extract weight. This substance was not identified by existing database, but its UV-spectrum was similar to those of

  18. The Matthew Effect in Environmental Science Publication: A Bibliometric Analysis of Chemical Substances in Journal Articles

    OpenAIRE

    Grandjean Philippe; Eriksen Mette L; Ellegaard Ole; Wallin Johan A

    2011-01-01

    Abstract Background While environmental research addresses scientific questions of possible societal relevance, it is unclear to what degree research focuses on environmental chemicals in need of documentation for risk assessment purposes. Methods In a bibliometric analysis, we used SciFinder to extract Chemical Abstract Service (CAS) numbers for chemicals addressed by publications in the 78 major environmental science journals during 2000-2009. The Web of Science was used to conduct title se...

  19. Chemical Analysis of Emu Feather Fiber Reinforced Epoxy Composites

    Directory of Open Access Journals (Sweden)

    V.Chandra sekhar

    2015-07-01

    Full Text Available A composite is usually made up of at least two materials out of which one is binding material called as matrix and other is a reinforcement material known as fiber. For the past ten years research is going on to explore possible composites with natural fiber like plant fibers and animal fibers. The important characteristics of composites are their strength, hardness light in weight. It is also necessary to study about the resistance of the composites for deferent chemicals. In the present work, composites prepared with epoxy (Araldite LY-556 as resin and „emu‟ bird feathers as fiber have been tested for chemical resistance. The composites were prepared by varying fiber loading (P of „emu‟ feathers ranging from 1 to 5 and length (L of feather fibers from 1 to 5 cm. The composites thus prepared were subjected to various chemicals (Acids, Alkalis, solvents etc.. Observations were plotted and studied. The results reveal that there will be weight gain for the composite samples after three days, when treated with Hydrochloric acid, Sodium carbonate, Acetic acid, Sodium hydroxide, Nitric acid and Ammonium hydroxide. Weight loss was observed for all the samples including pure epoxy when treated with Benzene, Carbon tetra chloride and Toluene.

  20. Neutron activation analysis for chemical characterization of Brazilian oxo-biodegradable plastics

    International Nuclear Information System (INIS)

    The chemical characterization of oxo-biodegradable plastic bags was performed by neutron activation analysis. The presence of several chemical elements (As, Br, Ca, Co, Cr, Fe, Hf, K, La, Na, Sb, Sc, Ta and Zn) with large variability of mass fractions amongst samples indicates that these plastics receive additives and may have been contaminated during manufacturing process thereby becoming potential environmental pollutants. (author)

  1. Forecasting global developments in the basic chemical industry for environmental policy analysis

    NARCIS (Netherlands)

    Broeren, M.L.M.; Saygin, D.; Patel, M.K.

    2014-01-01

    The chemical sector is the largest industrial energy user, but detailed analysis of its energy use developments lags behind other energy-intensive sectors. A cost-driven forecasting model for basic chemicals production is developed, accounting for regional production costs, demand growth and stock t

  2. Analysis of solids remaining following chemical cleaning in tank 6F

    International Nuclear Information System (INIS)

    Following chemical cleaning, a solid sample was collected and submitted to Savannah River National Laboratory (SRNL) for analysis. SRNL analyzed this sample by X-ray Diffraction (XRD) and scanning electron microscopy (SEM) to determine the composition of the solids remaining in Tank 6F and to assess the effectiveness of the chemical cleaning process.

  3. Mass spectrometry analysis of polychlorinated biphenyls: chemical ionization and selected ion chemical ionization using methane as a reagent gas

    Directory of Open Access Journals (Sweden)

    RAYMOND E. MARCH

    2000-06-01

    Full Text Available In the present paper a quadrupole ion trap mass spectrometer, coupled with a gas chromatograph, was used to compare the electron impact ionization (EI and chemical ionization (Cl technique, in terms of their selectivity in polychlorinated biphenyls (PCBs quantitative analysis. The experiments were carried out with a modified Varian SATURN III quadrupole ion-storage mass spectrometer equipped with Varian waveform generator, coupled with a gas chromatograph with DB-5 capillary column. The disadvantage of using EI in the analysis of PCBs congeners is the extensive fragmentation of the molecular ion. The main fragmentation pattern recorded in the EI mass spectra of PCBs was the loss of a chlorine atom from the molecular ion. Therefore the fragment-ion signal overlapped with the molecular-ion cluster of lower mass congener. The fragmentation reactions of PCBs are suppressed if methane is used as a reagent gas for chemical ionization, but fragment ions are also present in the spectrum as an obstruction for quantitative analysis. The most selective method for PCBs quantitative analysis appears to be Cl with mass-selected C2H5+ ions from methane, which results in a mass spectrum with a negligible amount of fragment ions.

  4. Statistical analysis of DNT detection using chemically functionalized microcantilever arrays

    DEFF Research Database (Denmark)

    Bosco, Filippo; Bache, M.; Hwu, E.-T.;

    2012-01-01

    The need for miniaturized and sensitive sensors for explosives detection is increasing in areas such as security and demining. Micrometer sized cantilevers are often used for label-free detection, and have previously been reported to be able to detect explosives. However, only a few measurements...... on the chemically treated surfaces results in significant bending of the cantilevers and in a decrease of their resonant frequencies. We present averaged measurements obtained from up to 72 cantilevers being simultaneously exposed to the same sample. Compared to integrated reference cantilevers with...

  5. Chemical analysis of acoustically levitated drops by Raman spectroscopy.

    Science.gov (United States)

    Tuckermann, Rudolf; Puskar, Ljiljana; Zavabeti, Mahta; Sekine, Ryo; McNaughton, Don

    2009-07-01

    An experimental apparatus combining Raman spectroscopy with acoustic levitation, Raman acoustic levitation spectroscopy (RALS), is investigated in the field of physical and chemical analytics. Whereas acoustic levitation enables the contactless handling of microsized samples, Raman spectroscopy offers the advantage of a noninvasive method without complex sample preparation. After carrying out some systematic tests to probe the sensitivity of the technique to drop size, shape, and position, RALS has been successfully applied in monitoring sample dilution and preconcentration, evaporation, crystallization, an acid-base reaction, and analytes in a surface-enhanced Raman spectroscopy colloidal suspension. PMID:19418043

  6. Chemical risk evaluation, importance of the risk analysis framework uses: Latin America development restrictions

    International Nuclear Information System (INIS)

    The power point presentation is about reach and results of the risk analysis in Venezuela, chemical dangers in food, human damage, injuries , technologies news in fodd development, toxicity, microbiological risk, technical recommendations

  7. A kinetic and equilibrium analysis of silicon carbide chemical vapor deposition on monofilaments

    Science.gov (United States)

    Gokoglu, S. A.; Kuczmarski, M. A.

    1993-01-01

    Chemical kinetics of atmospheric pressure silicon carbide (SiC) chemical vapor deposition (CVD) from dilute silane and propane source gases in hydrogen is numerically analyzed in a cylindrical upflow reactor designed for CVD on monofilaments. The chemical composition of the SiC deposit is assessed both from the calculated total fluxes of carbon and silicon and from chemical equilibrium considerations for the prevailing temperatures and species concentrations at and along the filament surface. The effects of gas and surface chemistry on the evolution of major gas phase species are considered in the analysis.

  8. Environmental Impact Assessment for Socio-Economic Analysis of Chemicals

    DEFF Research Database (Denmark)

    Calow, Peter; Biddinger, G; Hennes, C;

    This report describes the requirements for, and illustrates the application of, a methodology for a socio-economic analysis (SEA) especially as it might be adopted in the framework of REACH.......This report describes the requirements for, and illustrates the application of, a methodology for a socio-economic analysis (SEA) especially as it might be adopted in the framework of REACH....

  9. Analysis of Thermal Desorption System for the Chemical Treatment of Old Storages of Oil Based Mud

    OpenAIRE

    Tanweer Hussain; Abdul Rehman Memon; Javed Larik

    2013-01-01

    This paper presents an analysis for the chemical treatment of OBM (Oil Based Mud) used in the drilling process in the oil and gas industry. The analysis is based on OBM stored at ENI (Italian National Energy) gas fields at Bhit mount district Jamshoro since the last ten years that has been chemically and physically deteriorated. Characterization of various OBM samples was performed and these samples were processed in order to evaluate the best characteristics of the OBM for optimum treatment ...

  10. Chemical analysis of steel (citations from the NTIS Data Base). Report for 1964-Apr 80

    Energy Technology Data Exchange (ETDEWEB)

    Cavagnaro, D.M.

    1980-05-01

    Information is cited on chemical analysis of boron, nitrogen, hydrogen, sulfur, silicon, carbon, oxygen, aluminum, rare earths, and other trace elements in steel. In addition, research on the determination of major elements, including iron, is covered. New techniques and refinement of older techniques, including x-ray fluorescence, spectroscopy, chromatography, activation analysis, and wet chemical methods are also included. (This updated bibliography contains 240 abstracts, 14 of which are new entries to the previous edition.)

  11. ANALYSIS OF THE CHEMICAL COMPOSITION AND MORPHOLOGICAL STRUCTURE OF BANANA PSEUDO-STEM

    OpenAIRE

    Kun Li; Shiyu Fu; Huaiyu Zhan; Yao Zhan; Lucian A. Lucia

    2010-01-01

    An analysis of the chemical composition and anatomical structure of banana pseudo-stem was carried out using Light Microscopy (LM), Scanning Electron Microscopy (SEM), and Confocal Laser Scanning Microscopy (CLSM). The chemical analysis indicated there is a high holocellulose content and low lignin content in banana pseudo-stem compared with some other non-wood fiber resources. These results demonstrate that the banana pseudo-stem has potential value for pulping. In addition, we report for th...

  12. Chemical analysis of 24 dusty (pre-)main-sequence stars

    CERN Document Server

    Acke, B; Acke, Bram; Waelkens, Christoffel

    2004-01-01

    We have analysed the chemical photospheric composition of 24 Herbig Ae/Be and Vega-type stars in search for the lambda Bootis phenomenon. We present the results of the elemental abundances of the sample stars. Some of the stars were never before studied spectroscopically at optical wavelengths. We have determined the projected rotational velocities of our sample stars. Furthermore, we discuss stars that depict a (selective) depletion pattern in detail. HD 4881 and HD 139614 seem to display an overall deficiency. AB Aur and possibly HD 126367 have subsolar values for the iron abundance, but are almost solar in silicon. HD 100546 is the only clear lambda Bootis star in our sample.

  13. Probabilistic thermo-chemical analysis of a pultruded composite rod

    DEFF Research Database (Denmark)

    Baran, Ismet; Tutum, Cem Celal; Hattel, Jesper Henri

    2012-01-01

    case, the probabilistic design of the pultrusion process, which has not been considered until now, is performed. The effect of statistical variations in the material (i.e. fiber and resin) and resin kinetic properties, as well as process parameters such as pulling speed and inlet temperature...... on the product quality (degree of cure) are examined by means of Monte Carlo Simulation (MCS) with Latin Hypercube Sampling (LHS) technique. The variations in the activation energy as well as the density of the resin are found to have a strong influence on the centerline degree of cure at the exit whereas......In the present study the deterministic thermo-chemical pultrusion simulation of a composite rod taken from the literature [7] is used as a validation case. The predicted centerline temperature and cure degree profiles of the rod match well with those in the literature [7]. Following the validation...

  14. FINITE ELEMENT METHOD AND ANALYSIS FOR CHEMICAL-FLOODING SIMULATION

    Institute of Scientific and Technical Information of China (English)

    YUAN Yirang

    2000-01-01

    This article discusses the enhanced oil recovery numerical simulation of the chemical-flooding (such as surfactants, alcohol, polymers) composed of three-dimensional multicomponent, multiphase and incompressible mixed fluids. The mathematical model can be described as a coupled system of nonlinear partial differential equations with initialboundary value problems. From the actual conditions such as the effect of cross interference and the three-dimensional characteristic of large-scale science-engineering computation, this article puts forward a kind of characteristic finite element fractional step schemes and obtain the optimal order error estimates in L2 norm. Thus we have thoroughly solved the well-known theoretical problem proposed by a famous scientist, R. E. Ewing.

  15. Comprehensive Analysis Competence and Innovative Approaches for Sustainable Chemical Production.

    Science.gov (United States)

    Appel, Joerg; Colombo, Corrado; Dätwyler, Urs; Chen, Yun; Kerimoglu, Nimet

    2016-01-01

    Humanity currently sees itself facing enormous economic, ecological, and social challenges. Sustainable products and production in specialty chemistry are an important strategic element to address these megatrends. In addition to that, digitalization and global connectivity will create new opportunities for the industry. One aspect is examined in this paper, which shows the development of comprehensive analysis of production networks for a more sustainable production in which the need for innovative solutions arises. Examples from data analysis, advanced process control and automated performance monitoring are shown. These efforts have significant impact on improved yields, reduced energy and water consumption, and better product performance in the application of the products. PMID:27646543

  16. Comprehensive Analysis Competence and Innovative Approaches for Sustainable Chemical Production.

    Science.gov (United States)

    Appel, Joerg; Colombo, Corrado; Dätwyler, Urs; Chen, Yun; Kerimoglu, Nimet

    2016-01-01

    Humanity currently sees itself facing enormous economic, ecological, and social challenges. Sustainable products and production in specialty chemistry are an important strategic element to address these megatrends. In addition to that, digitalization and global connectivity will create new opportunities for the industry. One aspect is examined in this paper, which shows the development of comprehensive analysis of production networks for a more sustainable production in which the need for innovative solutions arises. Examples from data analysis, advanced process control and automated performance monitoring are shown. These efforts have significant impact on improved yields, reduced energy and water consumption, and better product performance in the application of the products.

  17. Synthesis and analysis in studies of chemical evolution

    Science.gov (United States)

    Ponnamperuma, C.; Hobish, M. K.; Kobayashi, K.; Hua, L. L.; Senaratne, N.

    1986-01-01

    Studies of the various processes that may have given rise to life on the Earth have demonstrated the appropriateness of an approach that makes use of analysis and synthesis. Analysis of extraterrestrial samples in the form of meteorites has demonstrated the presence of several precursors of biomolecules, most notably a full suite of nucleic acid bases and nucleotides of biological significance. These species were determined after exhaustive extraction of the sample and subsequent analysis using HPLC, GC, MS, and GC-MS. Procedural blanks indicate that these molecules are likely not the result of contamination during the extraction and analysis process. Similar species were found as products of spark discharge experiments in atmospheres thought to mimic primitive Earth conditions. These results indicate that the basic chemistry underlying these syntheses is common, and that life may not be unique to the Earth. Studies underway in the laboratory make use of proton nuclear magnetic resonance spectroscopy as a probe to assess associations between selected amino acids and any of several nucleotides comprising their genetic code and genetic anticode sequences. These studies demonstrate a clear selectivity by the anticode sequences, thus confirming the hydrophobicity studies performed by Lacey et al. These studies further support the contention that life is likely a natural result of the physics and chemistry of the universe.

  18. Chemical analysis of superconducting phase in K-doped picene.

    Science.gov (United States)

    Kambe, Takashi; Nishiyama, Saki; Nguyen, Huyen L T; Terao, Takahiro; Izumi, Masanari; Sakai, Yusuke; Zheng, Lu; Goto, Hidenori; Itoh, Yugo; Onji, Taiki; Kobayashi, Tatsuo C; Sugino, Hisako; Gohda, Shin; Okamoto, Hideki; Kubozono, Yoshihiro

    2016-11-01

    Potassium-doped picene (K3.0picene) with a superconducting transition temperature (T C) as high as 14 K at ambient pressure has been prepared using an annealing technique. The shielding fraction of this sample was 5.4% at 0 GPa. The T C showed a positive pressure-dependence and reached 19 K at 1.13 GPa. The shielding fraction also reached 18.5%. To investigate the chemical composition and the state of the picene skeleton in the superconducting sample, we used energy-dispersive x-ray (EDX) spectroscopy, MALDI-time-of-flight (MALDI-TOF) mass spectroscopy and x-ray diffraction (XRD). Both EDX and MALDI-TOF indicated no contamination with materials other than K-doped picene or K-doped picene fragments, and supported the preservation of the picene skeleton. However, it was also found that a magnetic K-doped picene sample consisted mainly of picene fragments or K-doped picene fragments. Thus, removal of the component contributing the magnetic quality to a superconducting sample should enhance the volume fraction. PMID:27604421

  19. Hydrocarbon analysis using desorption atmospheric pressure chemical ionization

    KAUST Repository

    Jjunju, Fred P M

    2013-07-01

    Characterization of the various petroleum constituents (hydronaphthalenes, thiophenes, alkyl substituted benzenes, pyridines, fluorenes, and polycyclic aromatic hydrocarbons) was achieved under ambient conditions without sample preparation by desorption atmospheric pressure chemical ionization (DAPCI). Conditions were chosen for the DAPCI experiments to control whether ionization was by proton or electron transfer. The protonated molecule [M+H]+ and the hydride abstracted [MH]+ form were observed when using an inert gas, typically nitrogen, to direct a lightly ionized plasma generated by corona discharge onto the sample surface in air. The abundant water cluster ions generated in this experiment react with condensed-phase functionalized hydrocarbon model compounds and their mixtures at or near the sample surface. On the other hand, when naphthalene was doped into the DAPCI gas stream, its radical cation served as a charge exchange reagent, yielding molecular radical cations (M+) of the hydrocarbons. This mode of sample ionization provided mass spectra with better signal/noise ratios and without unwanted side-products. It also extended the applicability of DAPCI to petroleum constituents which could not be analyzed through proton transfer (e.g., higher molecular PAHs such as chrysene). The thermochemistry governing the individual ionization processes is discussed and a desorption/ionization mechanism is inferred. © 2012 Elsevier B.V.

  20. Integrated separation and optical detection for novel on-chip chemical analysis

    Energy Technology Data Exchange (ETDEWEB)

    Warren, M.E.; Anex, D.S.; Rakestraw, D.; Gourley, P.L.

    1998-03-01

    This report represents the completion of a two years Laboratory Directed Research and Development (LDRD) program to investigate miniaturized systems for chemical detection and analysis. The future of advanced chemical detection and analysis is in miniature devices that are able to characterize increasingly complex samples, a laboratory on a chip. In this concept, chemical operations used to analyze complicated samples in a chemical laboratory sample handling, species separation, chemical derivitization and detection are incorporated into a miniature device. By using electrokinetic flow, this approach does not require pumps or valves, as fluids in microfabricated channels can be driven by externally applied voltages. This is ideal for sample handling in miniature devices. This project was to develop truly miniature on-chip optical systems based on Vertical Cavity Surface Emitting Lasers (VCSELs) and diffractive optics. These can be built into a complete system that also has on-chip electrokinetic fluid handling and chemical separation in a microfabricated column. The primary goal was the design and fabrication of an on-chip separation column with fluorescence sources and detectors that, using electrokinetic flow, can be used as the basis of an automated chemical analysis system. Secondary goals involved investigation of a dispersed fluorescence module that can be used to extend the versatility of the basic system and on chip, intracavity laser absorption as a high sensitivity detection technique.

  1. Virus and Bacterial Cell Chemical Analysis by NanoSIMS

    Energy Technology Data Exchange (ETDEWEB)

    Weber, P; Holt, J

    2008-07-28

    In past work for the Department of Homeland Security, the LLNL NanoSIMS team has succeeded in extracting quantitative elemental composition at sub-micron resolution from bacterial spores using nanometer-scale secondary ion mass spectrometry (NanoSIMS). The purpose of this task is to test our NanoSIMS capabilities on viruses and bacterial cells. This initial work has proven successful. We imaged Tobacco Mosaic Virus (TMV) and Bacillus anthracis Sterne cells using scanning electron microscopy (SEM) and then analyzed those samples by NanoSIMS. We were able resolve individual viral particles ({approx}18 nm by 300 nm) in the SEM and extract correlated elemental composition in the NanoSIMS. The phosphorous/carbon ratio observed in TMV is comparable to that seen in bacterial spores (0.033), as was the chlorine/carbon ratio (0.11). TMV elemental composition is consistent from spot to spot, and TMV is readily distinguished from debris by NanoSIMS analysis. Bacterial cells were readily identified in the SEM and relocated in the NanoSIMS for elemental analysis. The Ba Sterne cells were observed to have a measurably lower phosphorous/carbon ratio (0.005), as compared to the spores produced in the same run (0.02). The chlorine/carbon ratio was approximately 2.5X larger in the cells (0.2) versus the spores (0.08), while the fluorine/carbon ratio was approximately 10X lower in the cells (0.008) than the spores (0.08). Silicon/carbon ratios for both cells and spores encompassed a comparable range. The initial data in this study suggest that high resolution analysis is useful because it allows the target agent to be analyzed separate from particulates and other debris. High resolution analysis would also be useful for trace sample analysis. The next step in this work is to determine the potential utility of elemental signatures in these kinds of samples. We recommend bulk analyses of media and agent samples to determine the range of media compositions in use, and to determine how

  2. Different Models Used to Interpret Chemical Changes: Analysis of a Curriculum and Its Impact on French Students' Reasoning

    Science.gov (United States)

    Kermen, Isabelle; Meheut, Martine

    2009-01-01

    We present an analysis of the new French curriculum on chemical changes describing the underlying models and highlighting their relations to the empirical level. The authors of the curriculum introduced a distinction between the chemical change of a chemical system and the chemical reactions that account for it. We specify the different roles of…

  3. Advances in Mid-Infrared Spectroscopy for Chemical Analysis

    Science.gov (United States)

    Haas, Julian; Mizaikoff, Boris

    2016-06-01

    Infrared spectroscopy in the 3-20 μm spectral window has evolved from a routine laboratory technique into a state-of-the-art spectroscopy and sensing tool by benefitting from recent progress in increasingly sophisticated spectra acquisition techniques and advanced materials for generating, guiding, and detecting mid-infrared (MIR) radiation. Today, MIR spectroscopy provides molecular information with trace to ultratrace sensitivity, fast data acquisition rates, and high spectral resolution catering to demanding applications in bioanalytics, for example, and to improved routine analysis. In addition to advances in miniaturized device technology without sacrificing analytical performance, selected innovative applications for MIR spectroscopy ranging from process analysis to biotechnology and medical diagnostics are highlighted in this review.

  4. Archaeological and chemical analysis of Tell el Yahudiyeh ware

    Energy Technology Data Exchange (ETDEWEB)

    Kaplan, M F; Harbottle, G; Sayre, E V

    1978-01-01

    Typological and geographic analyses indicate that Tell el Yahudiyeh ware (found in Cyprus, Egypt, Nubia, and the Levant during the Middle Bronze period, c. 1750-1550 B.C.) were probably manufactured in two areas, the Nile Valley and the Levant. Activation analysis was carried out and correlated with the archaeological analyses. Results confirm the two ''families'' of the ware, one Egyptian and one Levantine. Speculations are offered on the social interaction of the period. 11 figures, 2 tables. (DLC)

  5. Chemical analysis of outgassing contaminants on spacecraft surfaces

    Science.gov (United States)

    Mcnutt, R. C.

    1973-01-01

    Methods for analyzing and characterizing outgassing contaminants from such materials as RTV 501 potting compound and S 13 G paint are presented. Fractional distillation of a gross distillate from RTV 501 rubber was carried out and the distilled fractions examined as to their ultraviolet and infrared spectra by gas liquid chromatography. A sensitive technique for structural analysis and molecular identification was found to consist of a gas chromatography-mass spectroscopy system, which was determined to be economically unfeasible at present.

  6. Archaeological and chemical analysis of Tell el Yahudiyeh ware

    International Nuclear Information System (INIS)

    Typological and geographic analyses indicate that Tell el Yahudiyeh ware (found in Cyprus, Egypt, Nubia, and the Levant during the Middle Bronze period, c. 1750-1550 B.C.) were probably manufactured in two areas, the Nile Valley and the Levant. Activation analysis was carried out and correlated with the archaeological analyses. Results confirm the two ''families'' of the ware, one Egyptian and one Levantine. Speculations are offered on the social interaction of the period. 11 figures, 2 tables

  7. The electron spectroscopy for chemical analysis microscopy beamline data acquisition system at ELETTRA

    Science.gov (United States)

    Gariazzo, C.; Krempaska, R.; Morrison, G. R.

    1996-07-01

    The electron spectroscopy for chemical analysis (ESCA) microscopy data acquisition system enables the user to control the imaging and spectroscopy modes of operation of the beamline ESCA microscopy at ELETTRA. It allows the user to integrate all experiment, beamline and machine operations in one single environment. The system also provides simple data analysis for both spectra and images data to guide further data acquisition.

  8. Inorganic chemical analysis of environmental materials—A lecture series

    Science.gov (United States)

    Crock, J.G.; Lamothe, P.J.

    2011-01-01

    At the request of the faculty of the Colorado School of Mines, Golden, Colorado, the authors prepared and presented a lecture series to the students of a graduate level advanced instrumental analysis class. The slides and text presented in this report are a compilation and condensation of this series of lectures. The purpose of this report is to present the slides and notes and to emphasize the thought processes that should be used by a scientist submitting samples for analyses in order to procure analytical data to answer a research question. First and foremost, the analytical data generated can be no better than the samples submitted. The questions to be answered must first be well defined and the appropriate samples collected from the population that will answer the question. The proper methods of analysis, including proper sample preparation and digestion techniques, must then be applied. Care must be taken to achieve the required limits of detection of the critical analytes to yield detectable analyte concentration (above "action" levels) for the majority of the study's samples and to address what portion of those analytes answer the research question-total or partial concentrations. To guarantee a robust analytical result that answers the research question(s), a well-defined quality assurance and quality control (QA/QC) plan must be employed. This QA/QC plan must include the collection and analysis of field and laboratory blanks, sample duplicates, and matrix-matched standard reference materials (SRMs). The proper SRMs may include in-house materials and/or a selection of widely available commercial materials. A discussion of the preparation and applicability of in-house reference materials is also presented. Only when all these analytical issues are sufficiently addressed can the research questions be answered with known certainty.

  9. Software for analysis of chemical mixtures--composition, occurrence, distribution, and possible toxicity

    Science.gov (United States)

    Scott, Jonathon C.; Skach, Kenneth A.; Toccalino, Patricia L.

    2013-01-01

    The composition, occurrence, distribution, and possible toxicity of chemical mixtures in the environment are research concerns of the U.S. Geological Survey and others. The presence of specific chemical mixtures may serve as indicators of natural phenomena or human-caused events. Chemical mixtures may also have ecological, industrial, geochemical, or toxicological effects. Chemical-mixture occurrences vary by analyte composition and concentration. Four related computer programs have been developed by the National Water-Quality Assessment Program of the U.S. Geological Survey for research of chemical-mixture compositions, occurrences, distributions, and possible toxicities. The compositions and occurrences are identified for the user-supplied data, and therefore the resultant counts are constrained by the user’s choices for the selection of chemicals, reporting limits for the analytical methods, spatial coverage, and time span for the data supplied. The distribution of chemical mixtures may be spatial, temporal, and (or) related to some other variable, such as chemical usage. Possible toxicities optionally are estimated from user-supplied benchmark data. The software for the analysis of chemical mixtures described in this report is designed to work with chemical-analysis data files retrieved from the U.S. Geological Survey National Water Information System but can also be used with appropriately formatted data from other sources. Installation and usage of the mixture software are documented. This mixture software was designed to function with minimal changes on a variety of computer-operating systems. To obtain the software described herein and other U.S. Geological Survey software, visit http://water.usgs.gov/software/.

  10. Embedded Fragments from U.S. Military Personnel—Chemical Analysis and Potential Health Implications

    OpenAIRE

    Centeno, José A.; Duane A. Rogers; Gijsbert B. van der Voet; Elisa Fornero; Lingsu Zhang; Mullick, Florabel G.; Chapman, Gail D.; Olabisi, Ayodele O.; Wagner, Dean J.; Alexander Stojadinovic; Potter, Benjamin K.

    2014-01-01

    Background: The majority of modern war wounds are characterized by high-energy blast injuries containing a wide range of retained foreign materials of a metallic or composite nature. Health effects of retained fragments range from local or systemic toxicities to foreign body reactions or malignancies, and dependent on the chemical composition and corrosiveness of the fragments in vivo. Information obtained by chemical analysis of excised fragments can be used to guide clinical decisions rega...

  11. Physico Chemical Analysis of Sapota (Manilkara zapota) Coated by Edible Aloe Vera Gel

    OpenAIRE

    N.Padmaja; S. John Don Bosco; J. Sudhakara Rao

    2015-01-01

    The physical and chemical characteristics of the fruit have immense significance as they ultimately affect the quality of processed productsprepared from them. Over ripening of Sapota (Manilkara zapota) fruits at the post-harvest stage usually results in dramatic decline in quality.In the present study, physico chemical analysis (which includes Weight loss, Colour, Texture, TSS, pH, TA and Ascorbic acid content) ofedible Aloe vera gel coated Sapota fruits packed in LDPE and stored at 15 ± 2? ...

  12. Permeability and chemical analysis of aromatic polyamide based membranes exposed to sodium hypochlorite

    OpenAIRE

    Ettori, Axel; Gaudichet-Maurin, Emmanuelle; Schrotter, Jean-Christophe; Aimar, Pierre; Causserand, Christel

    2011-01-01

    In this study, a cross-linked aromatic polyamide based reverse osmosis membrane was exposed to variable sodium hypochlorite ageing conditions (free chlorine concentration, solution pH) and the resulting evolutions of membrane surface chemical and structural properties were monitored. Elemental and surface chemical analysis performed using X-ray photoelectron spectroscopy (XPS) and Fourier transform infrared spectroscopy (FTIR), showed that chlorine is essentially incorporated on the polyamide...

  13. Analysis of abused drugs by selected ion monitoring: quantitative comparison of electron impact and chemical ionization

    International Nuclear Information System (INIS)

    A comparison was made of the relative sensitivities of electron impact and chemical ionization when used for selected ion monitoring analysis of commonly abused drugs. For most of the drugs examined chemical ionization using ammonia as the reactant gas gave the largest single m/e ion current response per unit weight of sample. However, if maximum sensitivity is desired it is important to evaluate electron impact and chemical ionization with respect to both maximum response and degree of interference from background and endogenous materials

  14. Organics. [Nature and analysis of chemical species in water systems

    Energy Technology Data Exchange (ETDEWEB)

    DeWalle, F.B. (Univ. of Washington, Seattle); Lo, C.; Sung, J.; Kalman, D.; Chian, E.S.K.; Giabbai, M.; Ghosal, M.

    1982-01-01

    This literature review presents an overview of nonspecific methods, followed by group and compound specific methods used in the analysis of detergents, aliphatic and aromatic hydrocarbons, pesticides and herbicides, and in process and industrially related compounds. Many studies are focused on polychlorinated biphenyls (PCB) because of their persistant character in nature even after a substantial decrease in usage. Their presence in sediments is correlated with organic matter and clay owing to their adsorption to these materials. They are also observed in effluents from combustion processes and in sludges from treatment units. Bacteria have been identified that degrade PCBs and give higher rates than the 1-year turnover rate observed in coastal waters. Industrially derived organics have been detected in surface and ground water, drinking water and waste water. Coal conversion processes can lead to releases of toxic nitrogen-containing compounds such as pyridines and sulfur heterocyclics. Included are 8 tables and 242 references. (JMT)

  15. The dilemma in prioritizing chemicals for environmental analysis: known versus unknown hazards.

    Science.gov (United States)

    Anna, Sobek; Sofia, Bejgarn; Christina, Rudén; Magnus, Breitholtz

    2016-08-10

    A major challenge for society is to manage the risks posed by the many chemicals continuously emitted to the environment. All chemicals in production and use cannot be monitored and science-based strategies for prioritization are essential. In this study we review available data to investigate which substances are included in environmental monitoring programs and published research studies reporting analyses of chemicals in Baltic Sea fish between 2000 and 2012. Our aim is to contribute to the discussion of priority settings in environmental chemical monitoring and research, which is closely linked to chemical management. In total, 105 different substances or substance groups were analyzed in Baltic Sea fish. Polychlorinated dibenzo-p-dioxins, polychlorinated dibenzofurans (PCDD/Fs) and polychlorinated biphenyls (PCBs) were the most studied substances or substance groups. The majority, 87%, of all analyses comprised 20% of the substances or substance groups, whereas 46 substance groups (44%) were analyzed only once. Almost three quarters of all analyses regarded a POP-substance (persistent organic pollutant). These results demonstrate that the majority of analyses on environmental contaminants in Baltic Sea fish concern a small number of already regulated chemicals. Legacy pollutants such as POPs pose a high risk to the Baltic Sea due to their hazardous properties. Yet, there may be a risk that prioritizations for chemical analyses are biased based on the knowns of the past. Such biases may lead to society failing in identifying risks posed by yet unknown hazardous chemicals. Alternative and complementary ways to identify priority chemicals are needed. More transparent communication between risk assessments performed as part of the risk assessment process within REACH and monitoring programs, and information on chemicals contained in consumer articles, would offer ways to identify chemicals for environmental analysis. PMID:27222376

  16. Environmental Chemical Analysis (by B. B. Kebbekus and S. Mitra)

    Science.gov (United States)

    Bower, Reviewed By Nathan W.

    1999-11-01

    This text helps to fill a void in the market, as there are relatively few undergraduate instrumental analysis texts designed specifically for the expanding population of environmental science students. R. N. Reeve's introductory, open-learning Environmental Analysis (Wiley, 1994) is one of the few, and it is aimed at a lower level and is less appropriate for traditional classroom study. Kebbekus and Mitra's book appears to be an update of I. Marr and M. Cresser's excellent 1983 text by the same name (and also published under the Chapman and Hall imprint). It assumes no background in instrumental methods of analysis but it does depend upon a good general chemistry background in kinetic and equilibrium calculations and the standard laboratory techniques found in a classical introduction to analytical chemistry. The slant taken by the authors is aimed more toward engineers, not only in the choice of topics, but also in how they are presented. For example, the statistical significance tests presented follow an engineering format rather than the standard used in analytical chemistry. This approach does not detract from the book's clarity. The writing style is concise and the book is generally well written. The earlier text, which has become somewhat of a classic, took the unusual step of teaching the instruments in the context of their environmental application. It was divided into sections on the "atmosphere", the "hydrosphere", the "lithosphere", and the "biosphere". This text takes a similar approach in the second half, with chapters on methods for air, water, and solid samples. Users who intend to use the book as a text instead of a reference will appreciate the addition of chapters in the first half of the book on spectroscopic, chromatographic, and mass spectrometric methods. The six chapters in these two parts of the book along with four chapters scattered throughout on environmental measurements, sampling, sample preparation, and quality assurance make a nice

  17. Chemical and Nutrient Analysis of Gingerbread Plum (Neocarya macrophylla Seeds

    Directory of Open Access Journals (Sweden)

    Tidjani Amza

    2010-07-01

    Full Text Available The proximate composition of gingerbread plum (Neocarya macrophylla seeds, mineral, fatty acid and amino acid compositions were evaluated. The proximate analysis revealed the following composition: moisture 10.57 and 10%, ash 4.43 and 6.43%, fat 47.28 and 2.14%, crude protein 20.37 and 61.71%, carbohydrates 8.64 and 12.10% and crude fiber 8.70 and 7.37% for Gingerbread Plum Seed Flour (GPSF and Defatted Gingerbread Plum Seed Flour (DGPSF respectively. Oleic, linoleic and arachidonic acids were the major unsaturated fatty acids with 47.15, 19.10 and 17.64% respectively. Saturated fatty acids accounted for 14.72% of total fatty acids. The main saturated fatty acids were palmitic and stearic, with minute amounts of arachidic. Magnesium, potassium and calcium were the predominant elements present in the seeds. Copper, iron and manganese were also detected in appreciable amounts. Essential amino acids were above the recommended amount by Food Agricultural Organization/W orld Health Organization (FAO/WHO for humans. The results of the present investigation showed that gingerbread plum seeds are a rich source of many important nutrients that appear to have a very positive effect on human health.

  18. Chemical analysis of Asymptotic Giant Branch stars in M62

    CERN Document Server

    Lapenna, E; Ferraro, F R; Origlia, L; Lanzoni, B; Massari, D; Dalessandro, E

    2015-01-01

    We have collected UVES-FLAMES high-resolution spectra for a sample of 6 asymptotic giant branch (AGB) and 13 red giant branch (RGB) stars in the Galactic globular cluster M62 (NGC6266). Here we present the detailed abundance analysis of iron, titanium, and light-elements (O, Na, Al and Mg). For the majority (5 out 6) of the AGB targets we find that the abundances, of both iron and titanium, determined from neutral lines are significantly underestimated with respect to those obtained from ionized features, the latter being, instead, in agreement with those measured for the RGB targets. This is similar to recent findings in other clusters and may suggest the presence of Non-Local Thermodynamical Equilibrium (NLTE) effects. In the O-Na, Al-Mg and Na-Al planes, the RGB stars show the typical correlations observed for globular cluster stars. Instead, all the AGB targets are clumped in the regions where first generation stars are expected to lie, similarly to what recently found for the AGB population of NGC6752. W...

  19. Multivariate data analysis for depth resolved chemical classification and quantification of sulfur in SNMS

    Science.gov (United States)

    Sommer, M.; Goschnick, J.

    2005-09-01

    The quantification of elements in quadrupole based SNMS is hampered by superpositions of atomic and cluster signals. Moreover, the conventional SNMS data evaluation employs only atomic signals to determine elemental concentrations, which not allows any chemical specifications of the determined elements. Improvements in the elemental quantification and additional chemical information can be obtained from kinetic energy analysis and the inclusion of molecular signals into mass spectra evaluation. With the help of multivariate data analysis techniques, the combined information is used for the first time for a quantitative and chemically distinctive determination of sulfur. The kinetic energy analysis, used to solve the interference of sulfur with O 2 at masses 32-34 D, turned out to be highly important for the new type of evaluation.

  20. Surface characterization and chemical analysis of bamboo substrates pretreated by alkali hydrogen peroxide.

    Science.gov (United States)

    Song, Xueping; Jiang, Yan; Rong, Xianjian; Wei, Wei; Wang, Shuangfei; Nie, Shuangxi

    2016-09-01

    The surface characterization and chemical analysis of bamboo substrates by alkali hydrogen peroxide pretreatment (AHPP) were investigated in this study. The results tended to manifest that AHPP prior to enzymatic and chemical treatment was potential for improving accessibility and reactivity of bamboo substrates. The inorganic components, organic solvent extractives and acid-soluble lignin were effectively removed by AHPP. X-ray photoelectron spectroscopy (XPS) analysis indicated that the surface of bamboo chips had less lignin but more carbohydrate after pre-treatment. Fiber surfaces became etched and collapsed, and more pores and debris on the substrate surface were observed with Scanning Electron Microscopy (SEM). Brenauer-Emmett-Teller (BET) results showed that both of pore volume and surface area were increased after AHPP. Although XRD analysis showed that AHPP led to relatively higher crystallinity, pre-extraction could overall enhance the accessibility of enzymes and chemicals into the bamboo structure. PMID:27311789

  1. Size distribution measurements and chemical analysis of aerosol components

    Energy Technology Data Exchange (ETDEWEB)

    Pakkanen, T.A.

    1995-12-31

    The principal aims of this work were to improve the existing methods for size distribution measurements and to draw conclusions about atmospheric and in-stack aerosol chemistry and physics by utilizing size distributions of various aerosol components measured. A sample dissolution with dilute nitric acid in an ultrasonic bath and subsequent graphite furnace atomic absorption spectrometric analysis was found to result in low blank values and good recoveries for several elements in atmospheric fine particle size fractions below 2 {mu}m of equivalent aerodynamic particle diameter (EAD). Furthermore, it turned out that a substantial amount of analyses associated with insoluble material could be recovered since suspensions were formed. The size distribution measurements of in-stack combustion aerosols indicated two modal size distributions for most components measured. The existence of the fine particle mode suggests that a substantial fraction of such elements with two modal size distributions may vaporize and nucleate during the combustion process. In southern Norway, size distributions of atmospheric aerosol components usually exhibited one or two fine particle modes and one or two coarse particle modes. Atmospheric relative humidity values higher than 80% resulted in significant increase of the mass median diameters of the droplet mode. Important local and/or regional sources of As, Br, I, K, Mn, Pb, Sb, Si and Zn were found to exist in southern Norway. The existence of these sources was reflected in the corresponding size distributions determined, and was utilized in the development of a source identification method based on size distribution data. On the Finnish south coast, atmospheric coarse particle nitrate was found to be formed mostly through an atmospheric reaction of nitric acid with existing coarse particle sea salt but reactions and/or adsorption of nitric acid with soil derived particles also occurred. Chloride was depleted when acidic species reacted

  2. Chemical analysis and quality control of Ginkgo biloba leaves, extracts, and phytopharmaceuticals

    OpenAIRE

    van Beek; Montoro, P.

    2009-01-01

    The chemical analysis and quality control of Ginkgo leaves, extracts, phytopharmaceuticals and some herbal supplements is comprehensively reviewed. The review is an update of a similar, earlier review in this journal [T.A. van Beek, J. Chromatogr. A 967 (2002) 21¿55]. Since 2001 over 3000 papers on Ginkgo biloba have appeared, and about 400 of them pertain to chemical analysis in a broad sense and are cited herein. The more important ones are discussed and, where relevant, compared with the b...

  3. Scanning angle Raman spectroscopy: Investigation of Raman scatter enhancement techniques for chemical analysis

    Energy Technology Data Exchange (ETDEWEB)

    Meyer, Matthew W. [Iowa State Univ., Ames, IA (United States)

    2013-01-01

    This thesis outlines advancements in Raman scatter enhancement techniques by applying evanescent fields, standing-waves (waveguides) and surface enhancements to increase the generated mean square electric field, which is directly related to the intensity of Raman scattering. These techniques are accomplished by employing scanning angle Raman spectroscopy and surface enhanced Raman spectroscopy. A 1064 nm multichannel Raman spectrometer is discussed for chemical analysis of lignin. Extending dispersive multichannel Raman spectroscopy to 1064 nm reduces the fluorescence interference that can mask the weaker Raman scattering. Overall, these techniques help address the major obstacles in Raman spectroscopy for chemical analysis, which include the inherently weak Raman cross section and susceptibility to fluorescence interference.

  4. Participation in the 1999 IAEA interlaboratory comparison on chemical analysis of groundwater

    Energy Technology Data Exchange (ETDEWEB)

    Joe, Kih Soo; Choi, Kwang Soon; Han, Sun Ho; Suh, Moo Yul; Park, Kyung Kyun; Choi, Ke Chun; Kim, Won Ho

    2000-08-01

    KAERI analytical laboratory participated in the 1999 IAEA interlaboratory comparison on chemical analysis of groundwater organized by IAEA Hydrology Laboratory(RAS/8/084). 13 items such as pH, electroconductivity, HCO{sub 3}, Cl, SO{sub 4}, NO{sub 3}, SiO{sub 2}, B, Li, Na, K, Ca, Mg were analyzed. The result of this program showed that KAERI laboratory was ranked within 10% range from top level. An analytical expert in KAERI attended the 'Consultants' Meeting' at IAEA headquater and prepared the guideline for chemical analysis of groundwater.

  5. 3D thermo-chemical-mechanical analysis of the pultrusion process

    DEFF Research Database (Denmark)

    Baran, Ismet; Hattel, Jesper Henri; Tutum, Cem C.

    2013-01-01

    In the present study, a 3D Eulerian thermo-chemical analysis is sequentially coupled with a 3D Lagrangian quasi static mechanical analysis of the pultrusion process. The temperature and degree of cure profiles at the steady state are first calculated in the thermo-chemical analysis....... In the mechanical analysis, the developments of the process induced stresses and distortions during the process are predicted using the already obtained temperature and degree of cure profiles together with the glass transition temperature. The predictions of the transverse transient stresses and distortions...... are found to be similar as compared to the available data in the literature. Using the proposed 3D mechanical analysis, different mechanical behaviour is obtained for the longitudinal stress development as distinct from the stress development in the transverse directions. Even though the matrix material...

  6. Biological and chemical removal of Cr(VI) from waste water: cost and benefit analysis.

    Science.gov (United States)

    Demir, Aynur; Arisoy, Münevver

    2007-08-17

    The objective of the present study is cost and benefit analysis of biological and chemical removal of hexavalent chromium [Cr(VI)] ions. Cost and benefit analysis were done with refer to two separate studies on removal of Cr(VI), one of heavy metals with a crucial role concerning increase in environmental pollution and disturbance of ecological balance, through biological adsorption and chemical ion-exchange. Methods of biological and chemical removal were compared with regard to their cost and percentage in chrome removal. According to the result of the comparison, cost per unit in chemical removal was calculated 0.24 euros and the ratio of chrome removal was 99.68%, whereas those of biological removal were 0.14 and 59.3% euros. Therefore, it was seen that cost per unit in chemical removal and chrome removal ratio were higher than those of biological removal method. In the current study where chrome removal is seen as immeasurable benefit in terms of human health and the environment, percentages of chrome removal were taken as measurable benefit and cost per unit of the chemicals as measurable cost.

  7. The Matthew effect in environmental science publication: A bibliometric analysis of chemical substances in journal articles

    DEFF Research Database (Denmark)

    Grandjean, Philippe; Eriksen, Mette Lindholm; Ellegaard, Ole;

    2011-01-01

    Chemical Abstract Service (CAS) numbers for chemicals addressed by publications in the 78 major environmental science journals during 2000-2009. The Web of Science was used to conduct title searches to determine longterm trends for prominent substances and substances considered in need of research......Background While environmental research addresses scientific questions of possible societal relevance, it is unclear to what degree research focuses on environmental chemicals in need of documentation for risk assessment purposes. Methods In a bibliometric analysis, we used SciFinder to extract...... attention. Results The 119,636 journal articles found had 760,056 CAS number links during 2000-2009. The top-20 environmental chemicals consisted of metals, (chlorinated) biphenyls, polyaromatic hydrocarbons, benzene, and ethanol and contributed 12% toward the total number of links- Each of the top-20...

  8. Application of physico-chemical procedures in the analysis of urinary calculi

    Energy Technology Data Exchange (ETDEWEB)

    Rodgers, A.L.

    1985-01-01

    All physico-chemical techniques used in the analysis of urinary calculi have inherent advantages and limitations. Although x-ray powder diffraction can identify constituents unambiguously, certain minor components can be missed. Infrared spectroscopy is more sensitive but band assignment at low concentrations is difficult. Scanning electron microscopy together with energy dispersive x-ray analysis permits the simultaneous investigation of morphology and chemical microstructure. With the electron microprobe, minor constituents can be detected but tedious sample preparation procedures are required. Transmission electron microscopy is extremely useful in determining constituent inter-relationships and ultrastructure but ultramicrotomy is very difficult. Thermal gravimetric analysis gives quantitative information easily but does not satisfactorily distinguish between struvite and brushite. In an attempt to assess the accuracy of chemical analyses, 62 calculi were investigated applying several chemical tests. Those for MgS , PO4(T ), NHU and uric acid proved highly reliable while that for CaS often yielded an incorrect result. The test for oxalate was totally unsatisfactory. Investigators of stone composition and structure should include x-ray diffraction (or infrared spectroscopy) and scanning electron microscopy as their methods of first choice. In addition, chemical or thermogravimetric analyses should be utilized in an auxiliary capacity.

  9. [Relativity of commercial specification of Menthae Herba based on chemical analysis].

    Science.gov (United States)

    Ye, Dan; Zhao, Ming; Shao, Yang; Ouyang, Zhen; Peng, Hua-sheng; Han Bang-xing; Zhang, Wei-wan-qi; Gu, Xue-mei

    2015-01-01

    In order to compare the differences of 35 Menthae Herba samples collected on the market and at producing areas, the contents of six total terpenoids, the essential oil and chromatographic fingerprints were analyzed, which provided evidences for drawing up the commodity specifications and grading criteria of Menthae Herba. GC-MS method was used to analyze the chemical constituents of 35 different samples. The chromatographic fingerprints obtained by using GC were then evaluated by similarity analysis, hierarchical clustering analysis and principal component analysis. The relativity between the content of six terpenoids and the essential oil were studied. In this study, the chemical profiles of 35 samples from different producing areas had significant disparity. All samples collected in the report could be categorized into four chemical types, L-menthol, pulegone, carvone and L-menthone, but the chemical profiles had no relationship with the areas. The chromatographic fingerprints of the samples from different types were dissimilar, while the different producing areas were difficult to be separated. It was indicated that the content of volatile oil was positively correlated with the content of L-menthol and the sum of six total terpenoids. The content of the essential oil, L-menthol and the sum of six total terpenoids of Menthae Herba were considered as one of the commercial specifications and grading criteria. These results in the research could be helpful to draw up the commercial specification and grading criteria of Menthae Herba from a view of chemical information.

  10. Forecasting global developments in the basic chemical industry for environmental policy analysis

    International Nuclear Information System (INIS)

    The chemical sector is the largest industrial energy user, but detailed analysis of its energy use developments lags behind other energy-intensive sectors. A cost-driven forecasting model for basic chemicals production is developed, accounting for regional production costs, demand growth and stock turnover. The model determines the global production capacity placement, implementation of energy-efficient Best Practice Technology (BPT) and global carbon dioxide (CO2) emissions for the period 2010–2030. Subsequently, the effects of energy and climate policies on these parameters are quantified. About 60% of new basic chemical production capacity is projected to be placed in non-OECD regions by 2030 due to low energy prices. While global production increases by 80% between 2010 and 2030, the OECD's production capacity share decreases from 40% to 20% and global emissions increase by 50%. Energy pricing and climate policies are found to reduce 2030 CO2 emissions by 5–15% relative to the baseline developments by increasing BPT implementation. Maximum BPT implementation results in a 25% reduction. Further emission reductions require measures beyond energy-efficient technologies. The model is useful to estimate general trends related to basic chemicals production, but improved data from the chemical sector is required to expand the analysis to additional technologies and chemicals. - Highlights: • We develop a global cost-driven forecasting model for the basic chemical sector. • We study regional production, energy-efficient technology, emissions and policies. • Between 2010 and 2030, 60% of new chemicals capacity is built in non-OECD regions. • Global CO2 emissions rise by 50%, but climate policies may limit this to 30–40%. • Measures beyond energy efficiency are needed to prevent increasing CO2 emissions

  11. Chemical structure of wood charcoal by infrared spectroscopy and multivariate analysis.

    Science.gov (United States)

    Labbé, Nicole; Harper, David; Rials, Timothy; Elder, Thomas

    2006-05-17

    In this work, the effect of temperature on charcoal structure and chemical composition is investigated for four tree species. Wood charcoal carbonized at various temperatures is analyzed by mid infrared spectroscopy coupled with multivariate analysis and by thermogravimetric analysis to characterize the chemical composition during the carbonization process. The multivariate models of charcoal were able to distinguish between species and wood thermal treatments, revealing that the characteristics of the wood charcoal depend not only on the wood species, but also on the carbonization temperature. This work demonstrates the potential of mid infrared spectroscopy in the whiskey industry, from the identification and classification of the wood species for the mellowing process to the chemical characterization of the barrels after the toasting and charring process. PMID:19127715

  12. Evaluation of C60 secondary ion mass spectrometry for the chemical analysis and imaging of fingerprints.

    Science.gov (United States)

    Sisco, Edward; Demoranville, Leonard T; Gillen, Greg

    2013-09-10

    The feasibility of using C60(+) cluster primary ion bombardment secondary ion mass spectrometry (C60(+) SIMS) for the analysis of the chemical composition of fingerprints is evaluated. It was found that C60(+) SIMS could be used to detect and image the spatial localization of a number of sebaceous and eccrine components in fingerprints. These analyses were also found to not be hindered by the use of common latent print powder development techniques. Finally, the ability to monitor the depth distribution of fingerprint constituents was found to be possible - a capability which has not been shown using other chemical imaging techniques. This paper illustrates a number of strengths and potential weaknesses of C60(+) SIMS as an additional or complimentary technique for the chemical analysis of fingerprints.

  13. Chemical Speciation Analysis and Environmental Behaviour of 127I and 129I

    DEFF Research Database (Denmark)

    Hansen, Violeta

    2011-01-01

    H. The absorption capacity of iodate is low and reduces quickly when its concentration increases. Compared with activated charcoal, DEAE 32 cellulose showed a lower adsorption capacity of inorganic and organic iodine species. Adsorption of iodine species onto activated charcoal and DEAE 32 cellulose from seawater......This thesis deals with chemical speciation analysis and behaviour of the anthropogenic radioisotope 129I as well as stable iodine 127I in environmental samples such as freshwater, seawater, soils, sediments and seaweed. The behaviour and chemical speciation of iodine (127I and 129I...... been present in the biosphere for a relatively short time, may not show the same behaviour as the stable 127I isotope. The present study illustrates this. Chemical speciation analysis of 129I and 127I as iodide, iodate and total inorganic iodine in seawater samples from the Baltic Proper, Skagerrak...

  14. Chemical Analysis of Exhaled Human Breath Using High Resolution Mm-Wave Rotational Spectra

    Science.gov (United States)

    Guo, Tianle; Branco, Daniela; Thomas, Jessica; Medvedev, Ivan; Dolson, David; Nam, Hyun-Joo; O, Kenneth

    2014-06-01

    High resolution rotational spectroscopy enables chemical sensors that are both sensitive and highly specific, which is well suited for analysis of expired human breath. We have previously reported on detection of breath ethanol, methanol, acetone, and acetaldehyde using THz sensors. This paper will outline our present efforts in this area, with specific focus on our ongoing quest to correlate levels of blood glucose with concentrations of a few breath chemicals known to be affected by elevated blood sugar levels. Prospects, challenges and future plans will be outlined and discussed. Fosnight, A.M., B.L. Moran, and I.R. Medvedev, Chemical analysis of exhaled human breath using a terahertz spectroscopic approach. Applied Physics Letters, 2013. 103(13): p. 133703-5.

  15. Recent Development in Optical Chemical Sensors Coupling with Flow Injection Analysis

    Directory of Open Access Journals (Sweden)

    Fuensanta Sánchez Rojas

    2006-10-01

    Full Text Available Optical techniques for chemical analysis are well established and sensors based on thesetechniques are now attracting considerable attention because of their importance in applications suchas environmental monitoring, biomedical sensing, and industrial process control. On the other hand,flow injection analysis (FIA is advisable for the rapid analysis of microliter volume samples and canbe interfaced directly to the chemical process. The FIA has become a widespread automatic analyticalmethod for more reasons; mainly due to the simplicity and low cost of the setups, their versatility, andease of assembling. In this paper, an overview of flow injection determinations by using opticalchemical sensors is provided, and instrumentation, sensor design, and applications are discussed. Thiswork summarizes the most relevant manuscripts from 1980 to date referred to analysis using opticalchemical sensors in FIA.

  16. Development of pure component property models for chemical product-process design and analysis

    DEFF Research Database (Denmark)

    Hukkerikar, Amol Shivajirao

    Property prediction models based on the group-contribution+ (GC+) approach have been developed to provide reliable predictions of pure component properties together with uncertainties of predicted property values which is much needed information in performing chemical product and process design...... into ProPred®, a property estimation toolbox of Integrated Computer Aided System, ICAS®, developed at CAPEC, DTU. Finally, a methodology for performing sensitivity analysis of process design due to uncertainties of property estimates is presented. This methodology allows the user to evaluate the effects...... and analysis of sustainable chemical processes. For developing property models, a systematic methodology for property modeling and uncertainty analysis is employed. The methodology includes a parameter estimation step to determine parameters of the property model and an uncertainty analysis step to establish...

  17. SWOT analysis for safer carriage of bulk liquid chemicals in tankers.

    Science.gov (United States)

    Arslan, Ozcan; Er, Ismail Deha

    2008-06-15

    The application of strengths, weaknesses, opportunities and threats (SWOT) analysis to formulation of strategy concerned with the safe carriage of bulk liquid chemicals in maritime tankers was examined in this study. A qualitative investigation using SWOT analysis has been implemented successfully for ships that are designed to carry liquid chemicals in bulk. The originality of this study lies in the use of SWOT analysis as a management tool to formulate strategic action plans for ship management companies, ship masters and officers for the carriage of dangerous goods in bulk. With this transportation-based SWOT analysis, efforts were made to explore the ways and means of converting possible threats into opportunities, and changing weaknesses into strengths; and strategic plans of action were developed for safer tanker operation. PMID:18093731

  18. SWOT analysis for safer carriage of bulk liquid chemicals in tankers.

    Science.gov (United States)

    Arslan, Ozcan; Er, Ismail Deha

    2008-06-15

    The application of strengths, weaknesses, opportunities and threats (SWOT) analysis to formulation of strategy concerned with the safe carriage of bulk liquid chemicals in maritime tankers was examined in this study. A qualitative investigation using SWOT analysis has been implemented successfully for ships that are designed to carry liquid chemicals in bulk. The originality of this study lies in the use of SWOT analysis as a management tool to formulate strategic action plans for ship management companies, ship masters and officers for the carriage of dangerous goods in bulk. With this transportation-based SWOT analysis, efforts were made to explore the ways and means of converting possible threats into opportunities, and changing weaknesses into strengths; and strategic plans of action were developed for safer tanker operation.

  19. Deconvolution-based resolution enhancement of chemical ice core records obtained by continuous flow analysis

    DEFF Research Database (Denmark)

    Rasmussen, Sune Olander; Andersen, Katrine K.; Johnsen, Sigfus Johann;

    2005-01-01

    Continuous flow analysis (CFA) has become a popular measuring technique for obtaining high-resolution chemical ice core records due to an attractive combination of measuring speed and resolution. However, when analyzing the deeper sections of ice cores or cores from low-accumulation areas, there ...

  20. Fertilizer/Chemical Sales and Service Worker. Ohio's Competency Analysis Profile.

    Science.gov (United States)

    Ohio State Univ., Columbus. Vocational Instructional Materials Lab.

    This Ohio Competency Analysis Profile (OCAP), derived from a modified Developing a Curriculum (DACUM) process, is a current comprehensive and verified employer competency program list for fertilizer/chemical sales and service workers. Each unit (with or without subunits) contains competencies and competency builders that identify the occupational,…

  1. Supramolecular chemical shift reagents inducing conformational transitions: NMR analysis of carbohydrate homooligomer mixtures

    DEFF Research Database (Denmark)

    Beeren, Sophie; Meier, Sebastian

    2015-01-01

    We introduce the concept of supramolecular chemical shift reagents as a tool to improve signal resolution for the NMR analysis of homooligomers. Non-covalent interactions with the shift reagent can constrain otherwise flexible analytes inducing a conformational transition that results in signal...

  2. Chemical analysis during lifecycle of munition; from Cradle-to-Grave (Poster)

    NARCIS (Netherlands)

    Hulst, M. van; Duvalois, W.; Klerk, W.P.C. de

    2009-01-01

    Chemical analysis is one of the most important parts within an energetic material lifecycle. It starts with the qualification and quantification of the raw materials and/or the intermediate materials used for the manufacturing of the final product. When the product is finished there is quality contr

  3. Chemical analysis during lifecycle of munition; from Cradle-to-Grave (Poster)

    OpenAIRE

    van Hulst, M.; Duvalois, W.; Klerk, W.P.C. de

    2009-01-01

    Chemical analysis is one of the most important parts within an energetic material lifecycle. It starts with the qualification and quantification of the raw materials and/or the intermediate materials used for the manufacturing of the final product. When the product is finished there is quality control and finally after functioning or demilitarisation components will end-up in the environment.

  4. Chemical analysis and quality control of Ginkgo biloba leaves, extracts, and phytopharmaceuticals

    NARCIS (Netherlands)

    Beek, van T.A.; Montoro, P.

    2009-01-01

    The chemical analysis and quality control of Ginkgo leaves, extracts, phytopharmaceuticals and some herbal supplements is comprehensively reviewed. The review is an update of a similar, earlier review in this journal [T.A. van Beek, J. Chromatogr. A 967 (2002) 21¿55]. Since 2001 over 3000 papers on

  5. On the graph and systems analysis of reversible chemical reaction networks with mass action kinetics

    NARCIS (Netherlands)

    Rao, Shodhan; Jayawardhana, Bayu; Schaft, Arjan van der

    2012-01-01

    Motivated by the recent progresses on the interplay between the graph theory and systems theory, we revisit the analysis of reversible chemical reaction networks described by mass action kinetics by reformulating it using the graph knowledge of the underlying networks. Based on this formulation, we

  6. Quantitative analysis of chemical elements in single cells using nuclear microprobe and nano-probe

    International Nuclear Information System (INIS)

    The study of the role of trace elements at cellular level requires the use of state-of-the-art analytical tools that could achieve enough sensitivity and spatial resolution. We developed a new methodology for the accurate quantification of chemical element distribution in single cells based on a combination of ion beam analysis techniques STIM, PIXE and RBS. The quantification procedure relies on the development of a STIM data analysis software (Paparamborde). Validity of this methodology and limits are discussed here. The method allows the quantification of trace elements (μg/g) with a 19.8 % uncertainty in cellular compartments with mass below 0.1 ng. The main limit of the method lies in the poor number of samples that can be analyzed, due to long irradiation times required and limited access to ion beam analysis facilities. This is the reason why we developed a database for cellular chemical composition capitalization (BDC4). BDC4 has been designed in order to use cellular chemical composition as a tracer for biological activities and is expected to provide in the future reference chemical compositions for any cellular type or compartment. Application of the STIM-PIXE-RBS methodology to the study of nuclear toxicology of cobalt compounds is presented here showing that STIM analysis is absolutely needed when organic mass loss appears during PIXE-RBS irradiation. (author)

  7. PHYSICO-CHEMICAL ANALYSIS OF FRESH AND FERMENTED FRUIT JUICES PROBIOTICATED WITH LACTOBACILLUS CASEI

    OpenAIRE

    Bathal Vijaya Kumar; Mannepula Sreedharamurthy; Obulam Vijaya Sarathi Reddy

    2013-01-01

    The objective of this study was to find out the suitability of different fruit juices for probiotication by using Lactobacillus casei. Phyto-chemical analysis of different fruit juices (mango, sapota, grape and cantaloupe) were carried out using the standard methods. Carbohydrates, flavoniods, tannins, glycosides were present and alkaloids and saponins were absent in all the above fruit juices. Further analysis by TLC and DPPH methods indicated good antioxidant activity in all the fruit juice...

  8. On the graph and systems analysis of reversible chemical reaction networks with mass action kinetics

    OpenAIRE

    Rao, Shodhan; Jayawardhana, Bayu; der Schaft, Arjan van

    2012-01-01

    Motivated by the recent progresses on the interplay between the graph theory and systems theory, we revisit the analysis of reversible chemical reaction networks described by mass action kinetics by reformulating it using the graph knowledge of the underlying networks. Based on this formulation, we can characterize the space of equilibrium points and provide simple dynamical analysis on the state space modulo the space of equilibrium points.

  9. Chemical data visualization and analysis with incremental generative topographic mapping: big data challenge.

    Science.gov (United States)

    Gaspar, Héléna A; Baskin, Igor I; Marcou, Gilles; Horvath, Dragos; Varnek, Alexandre

    2015-01-26

    This paper is devoted to the analysis and visualization in 2-dimensional space of large data sets of millions of compounds using the incremental version of generative topographic mapping (iGTM). The iGTM algorithm implemented in the in-house ISIDA-GTM program was applied to a database of more than 2 million compounds combining data sets of 36 chemicals suppliers and the NCI collection, encoded either by MOE descriptors or by MACCS keys. Taking advantage of the probabilistic nature of GTM, several approaches to data analysis were proposed. The chemical space coverage was evaluated using the normalized Shannon entropy. Different views of the data (property landscapes) were obtained by mapping various physical and chemical properties (molecular weight, aqueous solubility, LogP, etc.) onto the iGTM map. The superposition of these views helped to identify the regions in the chemical space populated by compounds with desirable physicochemical profiles and the suppliers providing them. The data sets similarity in the latent space was assessed by applying several metrics (Euclidean distance, Tanimoto and Bhattacharyya coefficients) to data probability distributions based on cumulated responsibility vectors. As a complementary approach, data sets were compared by considering them as individual objects on a meta-GTM map, built on cumulated responsibility vectors or property landscapes produced with iGTM. We believe that the iGTM methodology described in this article represents a fast and reliable way to analyze and visualize large chemical databases.

  10. Extracting chemical information from plane wave calculations by a 3D 'fuzzy atoms' analysis

    Science.gov (United States)

    Bakó, I.; Stirling, A.; Seitsonen, A. P.; Mayer, I.

    2013-03-01

    Bond order and valence indices have been calculated by the method of the three-dimensional 'fuzzy atoms' analysis, using the numerical molecular orbitals obtained from plane wave DFT calculations, i.e., without introducing any external atom-centered functions. Weight functions of both Hirshfeld and Becke types have been applied. The results are rather close to the similar 'fuzzy atoms' ones obtained by using atom-centered basis sets and agree well with the chemical expectations, stressing the power of the genuine chemical concepts.

  11. ANALYSIS OF CHEMICAL COMPOUNDS OF AGARWOOD OIL FROM DIFFERENT SPECIES BY GAS CHROMATOGRAPHY MASS SPECTROMETRY (GCMS)

    OpenAIRE

    Yumi Zuhanis Has-Yun Hashim; Nur Izzah Ismail; Phirdaous Abbas

    2014-01-01

    ABSTRACT: Agarwood oil is a highly prized type of oil due to its unique aroma. The oil is extracted from the fragrant resin found in the agarwood tree (trunk).  The unique aroma and quality of agarwood resin and oil are contributed by the presence of certain chemical compounds. In this work, analysis and comparison of the chemical compounds of agarwood oil from A. malaccensis, A. sub-integra and a mixture of both were conducted.  The essential oils were diluted in hexane (5%) prior to gas chr...

  12. Computer-Aided Modelling of Short-Path Evaporation for Chemical Product Purification, Analysis and Design

    DEFF Research Database (Denmark)

    Sales-Cruz, Alfonso Mauricio; Gani, Rafiqul

    2006-01-01

    An important stage in the design process for many chemical products is its manufacture where, for a class of chemical products that may be thermally unstable (such as, drugs, insecticides, flavours /fragrances, and so on), the purification step plays a major role. Short-path evaporation is a safe...... through a computer-aided modelling framework, which allows the use of systematic simulation strategies for various types of design/analysis problems. The main features of the model and the modelling framework are highlighted through two case studies: (a) the purification of a reaction mixture containing...

  13. Impact analysis of different chemical pre-treatments on colour of apple discs during drying process

    OpenAIRE

    Magdić, D.; Lukinac, Jasmina; Jokić, Stela; Čačić-Kenjerić, F.; Bilić, M.; Velić, D.

    2009-01-01

    The main purpose of this study was to compare colour changes of chemically pre-treated dried apple discs. Changes were observed by chromameter in L*a*b* colour model by using Minolta chromameter CR-400 and by image analysis system in RGB colour model. Apple discs variety "Gold Rush" were pre-treated and dried in laboratory tray drier at drying temperature 70 °C and at airflow velocity of 1.5 ms-1. Different chemical pre-treatments were applied on apple discs (dipping in 0.5% ascorbic acid sol...

  14. Thermodynamic and chemical kinetic analysis of a 5 kw, compact steam reformer - PEMFC system

    Energy Technology Data Exchange (ETDEWEB)

    Acevedo, Luis Evelio Garcia; Oliveira, Amir Antonio Martins [Universidade Federal de Santa Catarina (UFSC), Florianopolis, SC (Brazil). Dept. de Engenharia Mecanica], e-mail: evelio@labcet.ufsc.br, e-mail: amirol@emc.ufsc.br

    2006-07-01

    Here we present a thermodynamic and chemical kinetic analysis of the methane steam reforming for production of 5 kw of electrical power in a PEM fuel cell. The equilibrium analysis is based on the method of element potentials to find the state of minimum Gibbs free energy for the system and provides the equilibrium concentration of the reforming products. The objective of this analysis is to obtain the range of reforming temperature, pressure and steam-methane molar ratio that results in maximum hydrogen production subjected to low carbon monoxide production and negligible coke formation. The thermal analysis provides the heat transfer rates associated with the individual processes of steam production, gas-phase superheating and reforming necessary to produce 5 kw of electrical power in a PEM fuel cell and allows for the calculation of thermal efficiencies. Then, the chemical reaction pathways for hydrogen production in steam reforming are discussed and the available chemical, adsorption and equilibrium constants are analyzed in terms of thermodynamic consistency. This analysis provides the framework for the reactor sizing and for establishing the adequate operation conditions. (author)

  15. Sampling and chemical analysis in environmental samples around Nuclear Power Plants and some environmental samples

    Energy Technology Data Exchange (ETDEWEB)

    Cho, Yong Woo; Han, Man Jung; Cho, Seong Won; Cho, Hong Jun; Oh, Hyeon Kyun; Lee, Jeong Min; Chang, Jae Sook [KORTIC, Taejon (Korea, Republic of)

    2002-12-15

    Twelve kinds of environmental samples such as soil, seawater, underground water, etc. around Nuclear Power Plants(NPPs) were collected. Tritium chemical analysis was tried for the samples of rain water, pine-needle, air, seawater, underground water, chinese cabbage, a grain of rice and milk sampled around NPPs, and surface seawater and rain water sampled over the country. Strontium in the soil that sere sampled at 60 point of district in Korea were analyzed. Tritium were sampled at 60 point of district in Korea were analyzed. Tritium were analyzed in 21 samples of surface seawater around the Korea peninsular that were supplied from KFRDI(National Fisheries Research and Development Institute). Sampling and chemical analysis environmental samples around Kori, Woolsung, Youngkwang, Wooljin Npps and Taeduk science town for tritium and strontium analysis was managed according to plans. Succeed to KINS after all samples were tried.

  16. Humidity independent mass spectrometry for gas phase chemical analysis via ambient proton transfer reaction

    Energy Technology Data Exchange (ETDEWEB)

    Zhu, Hongying; Huang, Guangming, E-mail: gmhuang@ustc.edu.cn

    2015-03-31

    Graphical abstract: Direct and humidity independent mass spectrometry analysis of gas phase chemicals could be achieved via ambient proton transfer ionization, ion intensity was found to be stable with humidity ranged from ∼10% to ∼100%. - Highlights: • A humidity independent mass spectrometric method for gas phase samples analysis. • A universal and good sensitivity method. • The method can real time identify plant released raw chemicals. - Abstract: In this work, a humidity independent mass spectrometric method was developed for rapid analysis of gas phase chemicals. This method is based upon ambient proton transfer reaction between gas phase chemicals and charged water droplets, in a reaction chamber with nearly saturate humidity under atmospheric pressure. The humidity independent nature enables direct and rapid analysis of raw gas phase samples, avoiding time- and sample-consuming sample pretreatments in conventional mass spectrometry methods to control sample humidity. Acetone, benzene, toluene, ethylbenzene and meta-xylene were used to evaluate the analytical performance of present method. The limits of detection for benzene, toluene, ethylbenzene and meta-xylene are in the range of ∼0.1 to ∼0.3 ppbV; that of benzene is well below the present European Union permissible exposure limit for benzene vapor (5 μg m{sup −3}, ∼1.44 ppbV), with linear ranges of approximately two orders of magnitude. The majority of the homemade device contains a stainless steel tube as reaction chamber and an ultrasonic humidifier as the source of charged water droplets, which makes this cheap device easy to assemble and facile to operate. In addition, potential application of this method was illustrated by the real time identification of raw gas phase chemicals released from plants at different physiological stages.

  17. Humidity independent mass spectrometry for gas phase chemical analysis via ambient proton transfer reaction

    International Nuclear Information System (INIS)

    Graphical abstract: Direct and humidity independent mass spectrometry analysis of gas phase chemicals could be achieved via ambient proton transfer ionization, ion intensity was found to be stable with humidity ranged from ∼10% to ∼100%. - Highlights: • A humidity independent mass spectrometric method for gas phase samples analysis. • A universal and good sensitivity method. • The method can real time identify plant released raw chemicals. - Abstract: In this work, a humidity independent mass spectrometric method was developed for rapid analysis of gas phase chemicals. This method is based upon ambient proton transfer reaction between gas phase chemicals and charged water droplets, in a reaction chamber with nearly saturate humidity under atmospheric pressure. The humidity independent nature enables direct and rapid analysis of raw gas phase samples, avoiding time- and sample-consuming sample pretreatments in conventional mass spectrometry methods to control sample humidity. Acetone, benzene, toluene, ethylbenzene and meta-xylene were used to evaluate the analytical performance of present method. The limits of detection for benzene, toluene, ethylbenzene and meta-xylene are in the range of ∼0.1 to ∼0.3 ppbV; that of benzene is well below the present European Union permissible exposure limit for benzene vapor (5 μg m−3, ∼1.44 ppbV), with linear ranges of approximately two orders of magnitude. The majority of the homemade device contains a stainless steel tube as reaction chamber and an ultrasonic humidifier as the source of charged water droplets, which makes this cheap device easy to assemble and facile to operate. In addition, potential application of this method was illustrated by the real time identification of raw gas phase chemicals released from plants at different physiological stages

  18. Observations on the morphology and chemical analysis of medullary granules in chinchilla hair. Research letters

    Energy Technology Data Exchange (ETDEWEB)

    Keogh, H.J. (South African Inst. for Medical Research, Johannesburg); Haylett, T. (Council for Scientific and Industrial Research, Pretoria (South Africa). National Chemical Research Lab.)

    1983-02-01

    The ultrastructure of the medullary granules of white and grey chinchilla hair was investigated by scanning electron microscopy and chemical analysis in an attempt to clarify their structure and function. Atomic absorption spectroscopy and amino acid analysis showed them to be composed of melanin. The sample preparation for scanning electron microscopy is discussed. The metal content was qualitatively established by X-ray fluorescence spectrometry and quantitatively determined on a Varian Techtron model AAs atomic absorption spectrophotometer. Amino acid analysis of the granule, was carried out on a Beckman 121 amino acid analyser. Information is provided on the amino acid composition of the medullary granules as well as its metal content.

  19. Observations on the morphology and chemical analysis of medullary granules in chinchilla hair

    International Nuclear Information System (INIS)

    The ultrastructure of the medullary granules of white and grey chinchilla hair was investigated by scanning electron microscopy and chemical analysis in an attempt to clarify their structure and function. Atomic absorption spectroscopy and amino acid analysis showed them to be composed of melanin. The sample preparation for scanning electron microscopy is discussed. The metal content was qualitatively established by X-ray fluorescence spectrometry and quantitatively determined on a Varian Techtron model AAs atomic absorption spectrophotometer. Amino acid analysis of the granule, was carried out on a Beckman 121 amino acid analyser. Information is provided on the amino acid composition of the medullary granules as well as its metal content

  20. LSENS, a general chemical kinetics and sensitivity analysis code for gas-phase reactions: User's guide

    Science.gov (United States)

    Radhakrishnan, Krishnan; Bittker, David A.

    1993-01-01

    A general chemical kinetics and sensitivity analysis code for complex, homogeneous, gas-phase reactions is described. The main features of the code, LSENS, are its flexibility, efficiency and convenience in treating many different chemical reaction models. The models include static system, steady, one-dimensional, inviscid flow, shock initiated reaction, and a perfectly stirred reactor. In addition, equilibrium computations can be performed for several assigned states. An implicit numerical integration method, which works efficiently for the extremes of very fast and very slow reaction, is used for solving the 'stiff' differential equation systems that arise in chemical kinetics. For static reactions, sensitivity coefficients of all dependent variables and their temporal derivatives with respect to the initial values of dependent variables and/or the rate coefficient parameters can be computed. This paper presents descriptions of the code and its usage, and includes several illustrative example problems.

  1. Low Cost Long Distance Detector for Explosives and Chemical Analysis by IEC Application

    Directory of Open Access Journals (Sweden)

    George H. Miley

    2005-01-01

    Full Text Available A radiation source for detecting specific chemicals at several meter distances even behind walls, car doors or other barriers is the application of Million electron Volts (MeV neutrons from nuclear fusion reactions at such low intensities to avoid any danger for human bodies. The chemical analysis consists in the neutron activation of nuclei emitting then gamma radiation of lines very specific for the excited nuclei. The neutron generation by the Inertial Electrostatic Confinement (IEC had been developed to a level where very low cost neutron generators in mass production may be developed with a power supply from a normal AC plug-in or a battery. For specific chemicals e.g. the ratio of nitrogen against other elements used in all explosives, the selection of few specific gamma lines for the detectors may be of sufficiently low cost in the case of mass production.

  2. Physico Chemical Analysis of Sapota (Manilkara zapota Coated by Edible Aloe Vera Gel

    Directory of Open Access Journals (Sweden)

    N. Padmaja

    2015-03-01

    Full Text Available The physical and chemical characteristics of the fruit have immense significance as they ultimately affect the quality of processed productsprepared from them. Over ripening of Sapota (Manilkara zapota fruits at the post-harvest stage usually results in dramatic decline in quality.In the present study, physico chemical analysis (which includes Weight loss, Colour, Texture, TSS, pH, TA and Ascorbic acid content ofedible Aloe vera gel coated Sapota fruits packed in LDPE and stored at 15 ± 2? were studied at regular intervals of 5 days i.e., 0th,5th, 10th,15thand 20th days. The dip treatment of Aloe vera gel coating 1:2, 7 minutes had best retained the physico chemical characteristics than the othertreatments performed and was found to be the most effective treatment in maintaining the fruit quality attributes along with the shelf lifeextension of about 20 days.

  3. Prediction of chemical, physical and sensory data from process parameters for frozen cod using multivariate analysis

    DEFF Research Database (Denmark)

    Bechmann, Iben Ellegaard; Jensen, H.S.; Bøknæs, Niels;

    1998-01-01

    Physical, chemical and sensory quality parameters were determined for 115 cod (Gadus morhua) samples stored under varying frozen storage conditions. Five different process parameters (period of frozen storage, frozen storage. temperature, place of catch, season for catching and state of rigor) were....... PLS models that were able to predict the physical, chemical and sensory quality parameters from the process parameters of the frozen raw material were generated. The prediction abilities of the PLS models were good enough to give reasonable results even when the process parameters were characterised...... by ones and zeroes only. These results illustrate the application of multivariate analysis as an effective strategy for improving the quality of frozen fish products. (C) 1998 Society of Chemical Industry...

  4. The Matthew effect in environmental science publication: A bibliometric analysis of chemical substances in journal articles

    Directory of Open Access Journals (Sweden)

    Grandjean Philippe

    2011-11-01

    Full Text Available Abstract Background While environmental research addresses scientific questions of possible societal relevance, it is unclear to what degree research focuses on environmental chemicals in need of documentation for risk assessment purposes. Methods In a bibliometric analysis, we used SciFinder to extract Chemical Abstract Service (CAS numbers for chemicals addressed by publications in the 78 major environmental science journals during 2000-2009. The Web of Science was used to conduct title searches to determine long-term trends for prominent substances and substances considered in need of research attention. Results The 119,636 journal articles found had 760,056 CAS number links during 2000-2009. The top-20 environmental chemicals consisted of metals, (chlorinated biphenyls, polyaromatic hydrocarbons, benzene, and ethanol and contributed 12% toward the total number of links- Each of the top-20 substances was covered by 2,000-10,000 articles during the decade. The numbers for the 10-year period were similar to the total numbers of pre-2000 articles on the same chemicals. However, substances considered a high priority from a regulatory viewpoint, due to lack of documentation, showed very low publication rates. The persistence in the scientific literature of the top-20 chemicals was only weakly related to their publication in journals with a high impact factor, but some substances achieved high citation rates. Conclusions The persistence of some environmental chemicals in the scientific literature may be due to a 'Matthew' principle of maintaining prominence for the very reason of having been well researched. Such bias detracts from the societal needs for documentation on less well known environmental hazards, and it may also impact negatively on the potentials for innovation and discovery in research.

  5. Combined Micro-chemical and Micro-structural Analysis of New Minerals Representing Extreme Conditions

    Science.gov (United States)

    Ma, C.; Tschauner, O. D.

    2015-12-01

    Recent improvements in micro-chemical analysis in combination with novel tools for micrometer-scale structural analysis of minerals from synchrotron X-ray diffraction open a pathway towards studies of mineral paragenesis that were previously not or barely accessible. Often mineral assemblies that represent extreme conditions also pose extreme challenges to analysis: very small size scale, complex matrix, minor amounts of material. Examples of such extreme, but also quite relevant environments are: a) High pressure shock-metamorphic minerals in meteorites and terrestrial impact sites, b) inclusions in diamonds from the deep mantle, c) ultrarefractory phases in Ca-Al-inlcusions from the solar nebula, d) presolar condensates. We show how a combination of synchrotron-based structural and semi-quantitative chemical techniques, with electron-microscopy based high-resolution imaging and fully quantitative chemical analysis and qualitative structural identification establish a powerful tool for discovery and characterization of important and interesting new minerals on micron- to submicron size scale.

  6. Chemical and physical analysis of core materials for advanced high temperature reactors with process heat applications

    International Nuclear Information System (INIS)

    Various chemical and physical methods for the analysis of structural materials have been developed in the research programmes for advanced high temperature reactors. These methods are discussed using as examples the structural materials of the reactor core - the fuel elements consisting of coated particles in a graphite matrix and the structural graphite. Emphasis is given to the methods of chemical analysis. The composition of fuel kernels is investigated using chemical analysis methods to determine the heavy metals content (uranium, plutonium, thorium and metallic impurity elements) and the amount of non-metallic constituents. The properties of the pyrocarbon and silicon carbide coatings of fuel elements are investigated using specially developed physiochemical methods. Regarding the irradiation behaviour of coated particles and fuel elements, methods have been developed for examining specimens in hot cells following exposures under reactor operating conditions, to supplement the measurements of in-reactor performance. For the structural graphite, the determination of impurities is important because certain impurities may cause pitting corrosion during irradiation. The localized analysis of very low impurity concentrations is carried out using spectrochemical d.c. arc excitation, local laser and inductively coupled plasma methods. (orig.)

  7. Letters from China: A History of the Origins of the Chemical Analysis of Ceramics.

    Science.gov (United States)

    Pollard, A M

    2015-02-01

    This paper is an attempt to document the early history of the quantitative chemical analysis of ceramic materials in Europe, with a specific interest in the analysis of archaeological ceramics. This inevitably leads to a study of the attempts made in Europe to imitate the miraculous material--porcelain--imported from China from the fourteenth century onwards. It is clear that before the end of the eighteenth century progress was made in this endeavor by systematic but essentially trial-and-error firing of various raw materials, culminating in the successful production of European porcelain by Böttger and von Tschirnhaus in 1709. Shortly after this, letters describing the Chinese manufacture of porcelain, and, more importantly, samples of raw and fired material, began to arrive in Europe from French Jesuit missionaries, which were subjected to intense study. Following the perfection of gravimetric methods of chemical analysis in the late eighteenth century, these Chinese samples, and samples of porcelain from various European factories, were regularly analysed, particularly by Brongniart at Sèvres. Similar work was carried out on English porcelain by Simeon Shaw and Sir Arthur Church. The origins of the chemical analysis of archaeological ceramics are still somewhat obscure, but must date to the late eighteenth or early nineteenth centuries, by the likes of Vauquelin and Chaptal.

  8. USE OF AMAZONIAN SPECIES FOR AGING DISTILLED BEVERAGES: PHYSICAL AND CHEMICAL WOOD ANALYSIS

    Directory of Open Access Journals (Sweden)

    Jonnys Paz Castro

    2015-06-01

    Full Text Available The process of storing liquor in wooden barrels is a practice that aims to improve the sensory characteristics, such as color, aroma and flavor, of the beverage. The quality of the liquor stored in these barrels depends on wood characteristics such as density, permeability, chemical composition, anatomy, besides the wood heat treatment used to fabricate the barrels. Brazil has a great diversity of forests, mainly in the north, in the Amazon. This region is home to thousands of tree species, but is limited to the use of only a few native species to store liquors. The objective of this study was to determine some of the physical and chemical characteristics for four Amazon wood species. The results obtained in this study will be compared with others from woods that are traditionally used for liquor storage. The species studied were angelim-pedra (Hymenolobium petraeum Ducke cumarurana (Dipteryx polyphylla (Huber Ducke, jatobá (Hymenaea courbaril L. and louro-vermelho (Nectandra rubra (Mez CK Allen. The trees were collected from Precious Woods Amazon Company forest management area, in Silves, Amazonas. Analyzes such as: concentration of extractives, lignin amount, percentage of minerals (ash and tannin content, density, elemental analysis (CHNS-O and thermal analysis were done. It was observed that the chemical composition (lignin, holocellulose and elemental analysis (percentage of C, H, N and O of the woods have significant differences. The jatobá wood presented higher tannin content, and in the thermal analysis, was that which had the lowest mass loss.

  9. Analysis of pharmaceutical pellets: An approach using near-infrared chemical imaging

    Energy Technology Data Exchange (ETDEWEB)

    Sabin, Guilherme P.; Breitkreitz, Marcia C.; Souza, Andre M. de [Institute of Chemistry, University of Campinas, P.O. Box 6154, 13084-971 Campinas, SP (Brazil); Fonseca, Patricia da; Calefe, Lupercio; Moffa, Mario [Zelus Servicos para Industria Farmaceutica Ltda., Av. Professor Lineu Prestes n. 2242, Sao Paulo, SP (Brazil); Poppi, Ronei J., E-mail: ronei@iqm.unicamp.br [Institute of Chemistry, University of Campinas, P.O. Box 6154, 13084-971 Campinas, SP (Brazil)

    2011-11-07

    Highlights: {yields} Near-Infrared Chemical Imaging was used for pellets analysis. {yields} Distribution of the components throughout the coatings layers and core of the pellets was estimated. {yields} Classical Least Squares (CLS) was used for calculation of the concentration maps. - Abstract: Pharmaceutical pellets are spherical or nearly spherical multi-unit dosage forms designed to optimize pharmacokinetics and pharmacodynamics features of drug release. The distribution of the pharmaceutical ingredients in the layers and core is a very important parameter for appropriate drug release, especially for pellets manufactured by the process of layer gain. Physical aspects of the sample are normally evaluated by Scanning Electron Microscopy (SEM), but it is in many cases unsuitable to provide conclusive chemical information about the distribution of the pharmaceutical ingredients in both layers and core. On the other hand, methods based on spectroscopic imaging can be very promising for this purpose. In this work, a Near-Infrared Chemical Imaging (NIR-CI) method was developed and applied to the analysis of diclophenac sodium pellets. Since all the compounds present in the sample were known in advance, Classical Least Squares (CLS) was used for calculations. The results have shown that the method was capable of providing chemical information about the distribution of the active ingredient and excipients in the core and coating layers and therefore can be complementary to SEM for the pharmaceutical development of pellets.

  10. Analysis of changes in the chemical composition of the blast furnace coke at high temperatures

    Directory of Open Access Journals (Sweden)

    A. Konstanciak

    2012-12-01

    Full Text Available Purpose: The main purpose of this paper was to analyze the behavior of coke in the blast furnace. The analysis of changes in chemical composition of coke due to impact of inert gas and air at different temperatures was made. The impact of the application of the thermoabrasion coefficient on the porosity of coke was also analyzed.Design/methodology/approach: By applying the Computer Thermochemical Database of the TERMO system (REAKTOR1 and REAKTOR3 three groups of substances can be distinguished. The chemical composition of blast furnace coke and the results of calculations of changes of chemical composition of coke heat treated under certain conditions were compared. The structural studies of these materials were presented.Findings: The results of the analysis of ash produced from one of Polish cokes was taken for consideration. This is not the average composition of Polish coke ashes, nevertheless it is representative of most commonly occurring chemical compositions.Practical implications: Thanks to the thermochemical calculations it is possible to predict ash composition after the treatment in a blast furnace. Those information was crucial and had an actual impact on determining the coke quality.Originality/value: Presentation of the analytical methods which, according to author, can be very useful to evaluate and identify the heat treatment for blast furnaces cokes. The research pursued represents part of a larger project carried out within the framework of Department Extraction and Recycling of Metals, Czestochowa University of Technology.

  11. Phthalic Acid Chemical Probes Synthesized for Protein-Protein Interaction Analysis

    Directory of Open Access Journals (Sweden)

    Chin-Jen Wu

    2013-06-01

    Full Text Available Plasticizers are additives that are used to increase the flexibility of plastic during manufacturing. However, in injection molding processes, plasticizers cannot be generated with monomers because they can peel off from the plastics into the surrounding environment, water, or food, or become attached to skin. Among the various plasticizers that are used, 1,2-benzenedicarboxylic acid (phthalic acid is a typical precursor to generate phthalates. In addition, phthalic acid is a metabolite of diethylhexyl phthalate (DEHP. According to Gene_Ontology gene/protein database, phthalates can cause genital diseases, cardiotoxicity, hepatotoxicity, nephrotoxicity, etc. In this study, a silanized linker (3-aminopropyl triethoxyslane, APTES was deposited on silicon dioxides (SiO2 particles and phthalate chemical probes were manufactured from phthalic acid and APTES–SiO2. These probes could be used for detecting proteins that targeted phthalic acid and for protein-protein interactions. The phthalic acid chemical probes we produced were incubated with epithelioid cell lysates of normal rat kidney (NRK-52E cells to detect the interactions between phthalic acid and NRK-52E extracted proteins. These chemical probes interacted with a number of chaperones such as protein disulfide-isomerase A6, heat shock proteins, and Serpin H1. Ingenuity Pathways Analysis (IPA software showed that these chemical probes were a practical technique for protein-protein interaction analysis.

  12. Chemical analysis of fish bile extracts for monitoring endocrine disrupting chemical exposure in water: Bisphenol A, alkylphenols, and norethindrone.

    Science.gov (United States)

    Wu, Minghong; Pan, Chenyuan; Yang, Ming; Xu, Bentuo; Lei, Xiangjie; Ma, Jing; Cai, Ling; Chen, Jingsi

    2016-01-01

    The present study determined concentrations of estrogenic bisphenol A (BPA), nonylphenol, octylphenol (4-tert-octylphenol), butylphenol (4-tert-butylphenol), and progestogenic norethindrone by liquid chromatography-tandem mass spectrometry in bile extracts from field fish from the Xin'an River and market fish in Shanghai, China. Compared with the field fish, endocrine disrupting chemical (EDC) concentrations in market fish bile were at relatively high levels with high detectable rates. The average concentrations of BPA, nonylphenol, 4-tert-octylphenol, 4-tert-butylphenol, and norethindrone in field fish bile were 30.1 µg/L, 203 µg/L, 4.69 µg/L, 7.84 µg/L, and 0.514 µg/L, respectively; in market fish bile they were 240 µg/L, 528 µg/L, 76.5 µg/L, 12.8 µg/L, and 5.26 µg/L, respectively; and in the surface water of Xin'an River they were 38.8 ng/L, 7.91 ng/L, 1.98 ng/L, 2.66 ng/L, and 0.116 ng/L, respectively. The average of total estrogenic activity of river water was 3.32 ng/L estradiol equivalents. High bioconcentration factors (BCFs) were discovered for all 5 EDCs (≧998-fold) in field fish bile. Furthermore, the authors analyzed the BCF value of BPA in fish bile after 30-d exposure to environmentally relevant concentrations of BPA in the laboratory, and the analysis revealed that BCF in fish bile (BCF(Fish bile)) changed in an inverse concentration-dependent manner based on the log10-transformed BPA concentration in water. Strikingly, the data from the field study were well fitted within this trend. The data together suggested that analysis of fish bile extracts could be an efficient method for assessing waterborne EDCs exposure for aquatic biota.

  13. THz-Raman: accessing molecular structure with Raman spectroscopy for enhanced chemical identification, analysis, and monitoring

    Science.gov (United States)

    Heyler, Randy A.; Carriere, James T. A.; Havermeyer, Frank

    2013-05-01

    Structural analysis via spectroscopic measurement of rotational and vibrational modes is of increasing interest for many applications, since these spectra can reveal unique and important structural and behavioral information about a wide range of materials. However these modes correspond to very low frequency (~5cm-1 - 200cm-1, or 150 GHz-6 THz) emissions, which have been traditionally difficult and/or expensive to access through conventional Raman and Terahertz spectroscopy techniques. We report on a new, inexpensive, and highly efficient approach to gathering ultra-low-frequency Stokes and anti-Stokes Raman spectra (referred to as "THz-Raman") on a broad range of materials, opening potential new applications and analytical tools for chemical and trace detection, identification, and forensics analysis. Results are presented on explosives, pharmaceuticals, and common elements that show strong THz-Raman spectra, leading to clear discrimination of polymorphs, and improved sensitivity and reliability for chemical identification.

  14. Problem Based Learning (PBL: Analysis of Continuous Stirred Tank Chemical Reactors with a Process Control Approach

    Directory of Open Access Journals (Sweden)

    Regalado-Méndez Alejandro

    2010-10-01

    Full Text Available This work is focused on a project that integrates the curriculum such as thermodynamic, chemical reactorengineering, linear algebra, differential equations and computer programming. The purpose is thatstudents implement the most knowledge and tools to analyse the stirred tank chemical reactor as a simpledynamic system. When the students finished this practice they should have learned about analysis ofdynamic system through bifurcation analysis, hysteresis phenomena, find equilibrium points, stabilitytype, and phase portrait. Once the steps were accomplished, we concluded that the purpose wassatisfactorily reached with an increment in creative ability. The student showed a bigger interesting inthis practice, since they worked in group. The most important fact is that the percentage of failure amongstudents was 10%. Finally, using alternative teaching-learning process improves the Mexican systemeducation.

  15. HRI catalytic two-stage liquefaction (CTSL) process materials: chemical analysis and biological testing

    Energy Technology Data Exchange (ETDEWEB)

    Wright, C.W.; Later, D.W.

    1985-12-01

    This report presents data from the chemical analysis and biological testing of coal liquefaction materials obtained from the Hydrocarbon Research, Incorporated (HRI) catalytic two-stage liquefaction (CTSL) process. Materials from both an experimental run and a 25-day demonstration run were analyzed. Chemical methods of analysis included adsorption column chromatography, high-resolution gas chromatography, gas chromatography/mass spectrometry, low-voltage probe-inlet mass spectrometry, and proton nuclear magnetic resonance spectroscopy. The biological activity was evaluated using the standard microbial mutagenicity assay and an initiation/promotion assay for mouse-skin tumorigenicity. Where applicable, the results obtained from the analyses of the CTSL materials have been compared to those obtained from the integrated and nonintegrated two-stage coal liquefaction processes. 18 refs., 26 figs., 22 tabs.

  16. Quantitative analysis of abused drugs in physiological fluids by gas chromatography/chemical ionization mass spectrometry

    International Nuclear Information System (INIS)

    Methods have been developed for quantitative analysis of commonly abused drugs in physiological fluids using gas chromatography/chemical ionization mass spectrometry. The methods are being evaluated in volunteer analytical and toxicological laboratories, and analytical manuals describing the methods are being prepared. The specific drug and metabolites included in this program are: Δ9-tetrahydrocannabinol, methadone, phencyclidine, methaqualone, morphine, amphetamine, methamphetamine, mescaline, 2,5-dimethoxy-4-methyl amphetamine, cocaine, benzoylecgonine, diazepam, and N-desmethyldiazepam. The current analytical methods utilize relatively conventional instrumentation and procedures, and are capable of measuring drug concentrations as low as 1 ng/ml. Various newer techniques such as sample clean-up by high performance liquid chromatography, separation by glass capillary chromatography, and ionization by negative ion chemical ionization are being investigated with respect to their potential for achieving higher sensitivity and specificity, as well as their ability to facilitate simultaneous analysis of more than one drug and metabolite. (Auth.)

  17. Chemical imaging and solid state analysis at compact surfaces using UV imaging

    DEFF Research Database (Denmark)

    Wu, Jian X.; Rehder, Sönke; van den Berg, Frans;

    2014-01-01

    Fast non-destructive multi-wavelength UV imaging together with multivariate image analysis was utilized to visualize distribution of chemical components and their solid state form at compact surfaces. Amorphous and crystalline solid forms of the antidiabetic compound glibenclamide, and...... excipients in a non-invasive way, as well as mapping the glibenclamide solid state form. An exploratory data analysis supported the critical evaluation of the mapping results and the selection of model parameters for the chemical mapping. The present study demonstrated that the multi-wavelength UV imaging is...... microcrystalline cellulose together with magnesium stearate as excipients were used as model materials in the compacts. The UV imaging based drug and excipient distribution was in good agreement with hyperspectral NIR imaging. The UV wavelength region can be utilized in distinguishing between glibenclamide and...

  18. Quality assessment of mized fruit squash: physico-chemical analysis, senory evaluation and storage studies

    OpenAIRE

    Jothi, J.S.; Karmoker, P.; Sarower, K.

    2014-01-01

    Fruits and vegetables belong to an essential class of foods that supply human diet with nutritive requirements including vitamins and minerals which are essential for normal body health and function. The study was carried out to determine the physico-chemical analysis and sensory qualities of mixed fruit squash. Carrot (Drocus carota), papaya (Carica papaya) and banana (Musa sapientum) juice were standardized to produce mixed squash which was stored for 9 weeks in sterilized glass bottles at ...

  19. Chemical composition analysis of raw materials used in iron ore sinter plants in Poland

    Directory of Open Access Journals (Sweden)

    D. Burchart-Korol

    2014-07-01

    Full Text Available The main goal of the study was the analysis of the chemical compositions of raw materials used in iron ore sinter plants in Poland. The iron ore sintering process is the largest source of emissions of dust and gas pollution in the iron and steel industry. Hematite ores, magnetite concentrates, admixtures (dolomite, limestone and burnt lime, fuels (coke breeze, anthracite and by-products are used in Poland to produce the sinter mixture.

  20. "A Note on New Product Project Selection Model: Empirical Analysis in Chemical Industry" (in Japanese)

    OpenAIRE

    Kenichi Kuwashima; Junichi Tomita

    2001-01-01

    By focusing its attention on one particular scoring method that is used to evaluate R&D projects, this paper seeks to specify empirically the factors that discriminate successful projects from failed projects in the Japanese chemical industry. Our statistical analysis revealed that when projects are evaluated in this industry, three factors, marketability, technology, and synergistic potential, tend to be valued by practitioners approximately in a 3:2:1 ratio. Although the project evaluations...

  1. Patterns of innovation and organizational demography in emerging sustainable fields: an analysis of the chemical sector.

    OpenAIRE

    Marianna Epicoco

    2014-01-01

    This paper examines the eco-innovation dynamics in the chemical sector by analyzing Sustainable Chemistry (SC) technologies and the organizations that generated those technologies. First, we build an original dataset of patents and investigate trends emerging from patent statistics. Second, by using a clustering algorithm for the analysis of citation networks, we identify the main clusters of innovations that are driving the evolution of the field and analyze the demography of involved organi...

  2. Quality system of the Chemical Analysis Laboratory to fulfill the requirements with Certification Organizations

    International Nuclear Information System (INIS)

    In the present work was described the Quality System established in the Chemical Analysis Department to fulfill with the Organization requirements, personnel, measurement equipment, calibration, working procedures, etc. to get official acknowledgment by the National Assurance System for Testing laboratories, dependent of the General Standards Direction. There are described the available resources, the performance and control of each of one principal points of the system. (Author)

  3. Fourier-Domain Analysis of Hydriding Kinetics Using Pneumato-Chemical Impedance Spectroscopy

    OpenAIRE

    Millet, P.; C. Decaux; R. Ngameni; Guymont, M.

    2007-01-01

    Analysis of phase transformation processes observed in hydrogen absorbing materials (pure metals, alloys, or compounds) is still a matter of active research. Using pneumato-chemical impedance spectroscopy (PIS), it is now possible to analyze the mechanism of hydriding reactions induced by the gas phase. Experimental impedance diagrams, measured on activated LaNi5 in single- and two-phase domains, are reported in this paper. It is shown that their shape is mostly affected by the slope of the i...

  4. Evaluation of Three Flow Injection Analysis Methods for the Determination of Chemical Oxygen Demand

    OpenAIRE

    Korenaga, Takashi; Moriwake, Tosio; Takahashi, Teruo

    1984-01-01

    Three methods for determining chemical oxygen demand (COD) by means of flow injection analysis (FIA) with potassium permanganate, potassium dichromate, or cerium(IV) sulfate as oxidant, developed in this laboratory, are described from the point of view of their operating properties. The permanganate method is the most sensitive and common, but forms manganese(IV) oxide precipitate which blocks the FIA lines and connectors. Addition of phosphoric acid in the reagent system is, however, effecti...

  5. PHYSICO CHEMICAL ANALYSIS OF PANCHAVAKTRA RAS: A HERBO-MINERAL FORMULATION

    OpenAIRE

    Bandari Srinivasulu; P Bhadra Dev; P H C Murthy

    2013-01-01

    Panchavaktra Ras is a rational combination of Rasadravyas and Kasthaushadhis prescribed in the management of Amavata. Panchavaktra rasa has been taken into consideration for its Pharmaceutical standardization through Standard Operative procedures. In pharmaceutical study, the drug has been prepared in 3 batches adopting Khalviya Rasayana method and physico chemical analysis was carried out on these batches. This formulation was analysed by using Inductively Coupled Plasma with Optical Emissio...

  6. Chemical abundance analysis of symbiotic giants. RW Hya, SY Mus, BX Mon, and AE Ara

    CERN Document Server

    Galan, Cezary; Hinkle, Kenneth H; Schmidt, Miroslaw R; Gromadzki, Mariusz

    2014-01-01

    Symbiotic stars are the long period, binary systems of strongly interacting stars at the final stages of evolution which can be useful tool to understand the chemical evolution of the Galaxy and the formation of stellar populations. Knowledge of the chemical composition of the symbiotic giants is essential to advancing our understanding of these issues but unfortunately reliably determinations exist only in a few cases. We perform a program for detailed chemical composition analysis in over 30 symbiotic giants, based on the high resolution, near-IR spectra, obtained with Phoenix/Gemini South spectrometer. The methods of the standard LTE analysis is used to obtain photospheric abundances of CNO and elements around iron peak. Here we present results obtained for four objects: RW Hya, SY Mus, BX Mon, and AE Ara. Our analysis revealed a significantly sub-solar metallicity (Me/H ~ -0.75) for RW Hya, a slightly sub-solar metallicities (Me/H ~ 0.2-0.3) in BX Mon and AE Ara, and a near-solar metallicity in SY Mus. 12...

  7. Coupling passive sampling with in vitro bioassays and chemical analysis to understand combined effects of bioaccumulative chemicals in blood of marine turtles.

    Science.gov (United States)

    Jin, Ling; Escher, Beate I; Limpus, Colin J; Gaus, Caroline

    2015-11-01

    Conventional target analysis of biological samples such as blood limits our ability to understand mixture effects of chemicals. This study aimed to establish a rapid passive sampling technique using the polymer polydimethylsiloxane (PDMS) for exhaustive extraction of mixtures of neutral organic chemicals accumulated in blood of green turtles, in preparation for screening in in vitro bioassays. We designed a PDMS-blood partitioning system based on the partition coefficients of chemicals between PDMS and major blood components. The sampling kinetics of hydrophobic test chemicals (polychlorinated dibenzo-p-dioxins; PCDDs) from blood into PDMS were reasonably fast reaching steady state in turtles with known concentrations of PCDD/Fs, dioxin-like PCBs, PBDEs and organochlorine pesticides. The quantified chemicals explained most of the dioxin-like activity (69-98%), but less than 0.4% of the oxidative stress response. The results demonstrate the applicability of PDMS-based passive sampling to extract bioaccumulative chemicals from blood as well as the value of in vitro bioassays for capturing the combined effects of unknown and known chemicals.

  8. Meta-analysis of mass balances examining chemical fate during wastewater treatment.

    Science.gov (United States)

    Heidler, Jochen; Halden, Rolf U

    2008-09-01

    Mass balances are an instructive means for investigating the fate of chemicals during wastewater treatment. In addition to the aqueous-phase removal efficiency (phi), they can inform on chemical partitioning, transformation, and persistence, as well as on the chemical loading to streams and soils receiving, respectively, treated effluent and digested sewage sludge (biosolids). Release rates computed on a per-capita basis can serve to extrapolate findings to a larger scale. This review examines over a dozen mass balances conducted for various organic wastewater contaminants, including prescription drugs, estrogens, fragrances, antimicrobials, and surfactants of differing sorption potential (hydrophobicity), here expressed as the 1-octanol-water partition coefficient (K(OW)) and the organic carbon normalized sorption coefficient (K(OC)). Major challengesto mass balances are the collection of representative samples and accurate quantification of chemicals in sludge. A meta-analysis of peer-reviewed data identified sorption potential as the principal determinant governing chemical persistence in biosolids. Occurrence data for organic wastewater compounds detected in digested sludge followed a simple nonlinear model that required only K(OW) or K(OC) as the input and yielded a correlation coefficient of 0.9 in both instances. The model predicted persistence in biosolids for the majority (> 50%) of the input load of organic wastewater compounds featuring a log10 K(OW) value of greater than 5.2 (log10 K(OC) > 4.4). In contrast, hydrophobicity had no or only limited value for estimating, respectively, phi and the overall persistence of a chemical during conventional wastewater treatment.

  9. Hyphenation of sequential- and flow injection analysis with FTIR-spectroscopy for chemical analysis in aqueous solutions

    Science.gov (United States)

    Lendl, B.; Schindler, R.; Kellner, R.

    1998-06-01

    A survey of the principles of sequential (SIA)-and flow injection analysis (FIA) systems with FTIR spectroscopic detection is presented to introduce these hyphenations as powerful techniques for performing chemical analysis in aqueous solution. The strength of FIA/SIA-FTIR systems lies in the possibility to perform highly reproducible and automated sample manipulations such as sample clean-up and/or chemical reactions prior to spectrum acquisition. It is shown that the hyphenation of FIA/SIA systems with an FTIR spectrometer enhances the problem solving capabilities of the FTIR spectrometer as also parameters which can not be measured directly (e.g. enzyme activities) can be determined. On the other hand application of FTIR spectroscopic detection in FIA or SIA is also of advantage as it allows to shorten conventional analysis procedures (e.g. sucrose or phosphate analysis) or to establish and apply a multivariate calibration model for simultaneous determinations (e.g. glucose, fructose and sucrose analysis). In addition to these examples two recent instrumental developments in miniaturized FIA/SIA-FTIR systems, a μ-Flow through cell based on IR fiber optics and a micromachined SI-enzyme reactor are presented in this paper.

  10. Physical chemical analysis of marine sediment cementation from the Gulf of Guinea

    Science.gov (United States)

    Liu, Xianfeng; Hammad, Tammam; Saiyouri, Nadia; Hattab, Mahdia

    2012-09-01

    This study aims at investigating the cementation of marine sediments from the Gulf of Guinea by using physicochemical analysis. In order to highlight the presence of cementation in the sediments, three conventional consolidation tests were conducted on intact and remoulded samples. Mercury intrusion porosimetry analyses were then carried out on the specimens taken from samples after consolidation tests. Several physicochemical experimental techniques were used to analyze these cementations, such as cation exchange capacity analysis, batch test, scanning electron microscope imaging coupled with EDS chemical analysis, and thermal analysis. The results seem to indicate that the cementation of these sediments is predominated by the presence of smectite gel between clay aggregates (clusters). Finally, a conceptual sediment microstructural model is proposed to describe the cementation.

  11. A chemical profiling strategy for semi-quantitative analysis of flavonoids in Ginkgo extracts.

    Science.gov (United States)

    Yang, Jing; Wang, An-Qi; Li, Xue-Jing; Fan, Xue; Yin, Shan-Shan; Lan, Ke

    2016-05-10

    Flavonoids analysis in herbal products is challenged by their vast chemical diversity. This work aimed to develop a chemical profiling strategy for the semi-quantification of flavonoids using extracts of Ginkgo biloba L. (EGB) as an example. The strategy was based on the principle that flavonoids in EGB have an almost equivalent molecular absorption coefficient at a fixed wavelength. As a result, the molecular-contents of flavonoids were able to be semi-quantitatively determined by the molecular-concentration calibration curves of common standards and recalculated as the mass-contents with the characterized molecular weight (MW). Twenty batches of EGB were subjected to HPLC-UV/DAD/MS fingerprinting analysis to test the feasibility and reliability of this strategy. The flavonoid peaks were distinguished from the other peaks with principle component analysis and Pearson correlation analysis of the normalized UV spectrometric dataset. Each flavonoid peak was subsequently tentatively identified by the MS data to ascertain their MW. It was highlighted that the flavonoids absorption at Band-II (240-280 nm) was more suitable for the semi-quantification purpose because of the less variation compared to that at Band-I (300-380 nm). The semi-quantification was therefore conducted at 254 nm. Beyond the qualitative comparison results acquired by common chemical profiling techniques, the semi-quantitative approach presented the detailed compositional information of flavonoids in EGB and demonstrated how the adulteration of one batch was achieved. The developed strategy was believed to be useful for the advanced analysis of herbal extracts with a high flavonoid content without laborious identification and isolation of individual components. PMID:26907698

  12. Analysis of Chemical Constituents in Wuzi-Yanzong-Wan by UPLC-ESI-LTQ-Orbitrap-MS

    Directory of Open Access Journals (Sweden)

    Dixin Zou

    2015-12-01

    Full Text Available Wuzi-Yanzong-Wan (WZYZW, a classical traditional Chinese medicine (TCM prescription containing Fructus Lych, Semen Cuscutae (fried, Fructus Rubi, Fructus Schisandrae chinensis (steamed and Semen Plantaginis (fried with salt, is widely used to treat impotence, sterility, spermatorrhea, premature ejaculation, lumbago and post-micturation dribble. However, the chemical profile of WZYZW has not been established yet. In this work, a rapid and sensitive method for systematically screening and identifying the chemical constituents of WZYZW in both positive and negative ion modes using Ultra-Performance LC coupled with ESI-linear ion trap-Orbitrap tandem mass spectrometry (UPLC-ESI-LTQ-Orbitrap-MS has been developed. Based on the chromatographic and spectrometric data, and referring to the literature, we could tentatively identify 106 compounds, including organic acids, flavonoids, phenylpropanoids, alkaloids and terpenoids. Fourteen ingredients from Fructus Lych were identified, while 10 ingredients were from Semen Cuscutae (fried, 33 ingredients were from Fructus Rubi, 37 ingredients were from Fructus Schisandrae chinensis (steamed, and 20 ingredients were from Semen Plantaginis (fried with salt. The results may provide essential data for further quality control, pharmacological research and clinical evaluation of WZYZW. Furthermore, this study indicates the developed approach based on UPLC-ESI-LTQ-Orbitrap-MS is suitable for characterizing the chemical profiles of TCM prescriptions. This is the first report to provide a comprehensive analysis of the chemical constituents of WZYZW.

  13. Analysis of Chemical Constituents in Wuzi-Yanzong-Wan by UPLC-ESI-LTQ-Orbitrap-MS.

    Science.gov (United States)

    Zou, Dixin; Wang, Jinfeng; Zhang, Bo; Xie, Suhua; Wang, Qing; Xu, Kexin; Lin, Ruichao

    2015-01-01

    Wuzi-Yanzong-Wan (WZYZW), a classical traditional Chinese medicine (TCM) prescription containing Fructus Lych, Semen Cuscutae (fried), Fructus Rubi, Fructus Schisandrae chinensis (steamed) and Semen Plantaginis (fried with salt), is widely used to treat impotence, sterility, spermatorrhea, premature ejaculation, lumbago and post-micturation dribble. However, the chemical profile of WZYZW has not been established yet. In this work, a rapid and sensitive method for systematically screening and identifying the chemical constituents of WZYZW in both positive and negative ion modes using Ultra-Performance LC coupled with ESI-linear ion trap-Orbitrap tandem mass spectrometry (UPLC-ESI-LTQ-Orbitrap-MS) has been developed. Based on the chromatographic and spectrometric data, and referring to the literature, we could tentatively identify 106 compounds, including organic acids, flavonoids, phenylpropanoids, alkaloids and terpenoids. Fourteen ingredients from Fructus Lych were identified, while 10 ingredients were from Semen Cuscutae (fried), 33 ingredients were from Fructus Rubi, 37 ingredients were from Fructus Schisandrae chinensis (steamed), and 20 ingredients were from Semen Plantaginis (fried with salt). The results may provide essential data for further quality control, pharmacological research and clinical evaluation of WZYZW. Furthermore, this study indicates the developed approach based on UPLC-ESI-LTQ-Orbitrap-MS is suitable for characterizing the chemical profiles of TCM prescriptions. This is the first report to provide a comprehensive analysis of the chemical constituents of WZYZW. PMID:26633334

  14. Embedded Fragments from U.S. Military Personnel—Chemical Analysis and Potential Health Implications

    Directory of Open Access Journals (Sweden)

    José A. Centeno

    2014-01-01

    Full Text Available Background: The majority of modern war wounds are characterized by high-energy blast injuries containing a wide range of retained foreign materials of a metallic or composite nature. Health effects of retained fragments range from local or systemic toxicities to foreign body reactions or malignancies, and dependent on the chemical composition and corrosiveness of the fragments in vivo. Information obtained by chemical analysis of excised fragments can be used to guide clinical decisions regarding the need for fragment removal, to develop therapeutic interventions, and to better anticipate future medical problems from retained fragment related injuries. In response to this need, a new U.S Department of Defense (DoD directive has been issued requiring characterization of all removed fragments to provide a database of fragment types occurring in combat injuries. Objectives: The objective of this study is to determine the chemical composition of retained embedded fragments removed from injured military personnel, and to relate results to histological findings in tissue adjacent to fragment material. Methods: We describe an approach for the chemical analysis and characterization of retained fragments and adjacent tissues, and include case examples describing fragments containing depleted uranium (DU, tungsten (W, lead (Pb, and non-metal foreign bodies composed of natural and composite materials. Fragments obtained from four patients with penetrating blast wounds to the limbs were studied employing a wide range of chemical and microscopy techniques. Available adjacent tissues from three of the cases were histologically, microscopically, and chemically examined. The physical and compositional properties of the removed foreign material surfaces were examined with energy dispersive x-ray fluorescence spectrometry (EDXRF, scanning electron microscopy (SEM, laser ablation inductively-coupled plasma mass-spectrometry (LA-ICP-MS, and confocal laser Raman

  15. Embedded Fragments from U.S. Military Personnel—Chemical Analysis and Potential Health Implications

    Science.gov (United States)

    Centeno, José A.; Rogers, Duane A.; van der Voet, Gijsbert B.; Fornero, Elisa; Zhang, Lingsu; Mullick, Florabel G.; Chapman, Gail D.; Olabisi, Ayodele O.; Wagner, Dean J.; Stojadinovic, Alexander; Potter, Benjamin K.

    2014-01-01

    Background: The majority of modern war wounds are characterized by high-energy blast injuries containing a wide range of retained foreign materials of a metallic or composite nature. Health effects of retained fragments range from local or systemic toxicities to foreign body reactions or malignancies, and dependent on the chemical composition and corrosiveness of the fragments in vivo. Information obtained by chemical analysis of excised fragments can be used to guide clinical decisions regarding the need for fragment removal, to develop therapeutic interventions, and to better anticipate future medical problems from retained fragment related injuries. In response to this need, a new U.S Department of Defense (DoD) directive has been issued requiring characterization of all removed fragments to provide a database of fragment types occurring in combat injuries. Objectives: The objective of this study is to determine the chemical composition of retained embedded fragments removed from injured military personnel, and to relate results to histological findings in tissue adjacent to fragment material. Methods: We describe an approach for the chemical analysis and characterization of retained fragments and adjacent tissues, and include case examples describing fragments containing depleted uranium (DU), tungsten (W), lead (Pb), and non-metal foreign bodies composed of natural and composite materials. Fragments obtained from four patients with penetrating blast wounds to the limbs were studied employing a wide range of chemical and microscopy techniques. Available adjacent tissues from three of the cases were histologically, microscopically, and chemically examined. The physical and compositional properties of the removed foreign material surfaces were examined with energy dispersive x-ray fluorescence spectrometry (EDXRF), scanning electron microscopy (SEM), laser ablation inductively-coupled plasma mass-spectrometry (LA-ICP-MS), and confocal laser Raman

  16. Chemical composition dispersion in bi-metallic nanoparticles: semi-automated analysis using HAADF-STEM

    Energy Technology Data Exchange (ETDEWEB)

    Epicier, T., E-mail: thierry.epicier@insa-lyon.fr [INSA-Lyon, MATEIS CNRS UMR5510, Bat. Blaise Pascal (France); Sato, K. [Institute for Materials Research, Tohoku University, Material Processing and Characterization Division (Japan); Tournus, F. [Universite Lyon 1, LPMCN, UMR 5586 CNRS and Universite de Lyon (France); Konno, T. [Institute for Materials Research, Tohoku University, Material Processing and Characterization Division (Japan)

    2012-09-15

    We present a method using high-angle annular dark field scanning transmission electron microscopy (HAADF-STEM) to determine the chemical composition of bi-metallic nanoparticles. This method, which can be applied in a semi-automated way, allows large scale analysis with a statistical number of particles (several hundreds) in a short time. Once a calibration curve has been obtained, e.g., using energy-dispersive X-ray spectroscopy (EDX) measurements on a few particles, the HAADF integrated intensity of each particle can indeed be directly related to its chemical composition. After a theoretical description, this approach is applied to the case of iron-palladium nanoparticles (expected to be nearly stoichiometric) with a mean size of 8.3 nm. It will be shown that an accurate chemical composition histogram is obtained, i.e., the Fe content has been determined to be 49.0 at.% with a dispersion of 10.4 %. HAADF-STEM analysis represents a powerful alternative to fastidious single particle EDX measurements, for the compositional dispersion in alloy nanoparticles.

  17. Application of quantum dots as analytical tools in automated chemical analysis: A review

    Energy Technology Data Exchange (ETDEWEB)

    Frigerio, Christian; Ribeiro, David S.M.; Rodrigues, S. Sofia M.; Abreu, Vera L.R.G.; Barbosa, Joao A.C.; Prior, Joao A.V.; Marques, Karine L. [REQUIMTE, Laboratory of Applied Chemistry, Department of Chemical Sciences, Faculty of Pharmacy of Porto University, Rua Jorge Viterbo Ferreira, 228, 4050-313 Porto (Portugal); Santos, Joao L.M., E-mail: joaolms@ff.up.pt [REQUIMTE, Laboratory of Applied Chemistry, Department of Chemical Sciences, Faculty of Pharmacy of Porto University, Rua Jorge Viterbo Ferreira, 228, 4050-313 Porto (Portugal)

    2012-07-20

    Highlights: Black-Right-Pointing-Pointer Review on quantum dots application in automated chemical analysis. Black-Right-Pointing-Pointer Automation by using flow-based techniques. Black-Right-Pointing-Pointer Quantum dots in liquid chromatography and capillary electrophoresis. Black-Right-Pointing-Pointer Detection by fluorescence and chemiluminescence. Black-Right-Pointing-Pointer Electrochemiluminescence and radical generation. - Abstract: Colloidal semiconductor nanocrystals or quantum dots (QDs) are one of the most relevant developments in the fast-growing world of nanotechnology. Initially proposed as luminescent biological labels, they are finding new important fields of application in analytical chemistry, where their photoluminescent properties have been exploited in environmental monitoring, pharmaceutical and clinical analysis and food quality control. Despite the enormous variety of applications that have been developed, the automation of QDs-based analytical methodologies by resorting to automation tools such as continuous flow analysis and related techniques, which would allow to take advantage of particular features of the nanocrystals such as the versatile surface chemistry and ligand binding ability, the aptitude to generate reactive species, the possibility of encapsulation in different materials while retaining native luminescence providing the means for the implementation of renewable chemosensors or even the utilisation of more drastic and even stability impairing reaction conditions, is hitherto very limited. In this review, we provide insights into the analytical potential of quantum dots focusing on prospects of their utilisation in automated flow-based and flow-related approaches and the future outlook of QDs applications in chemical analysis.

  18. Comparing chemical analysis with literature studies to identify micropollutants in a catchment of Copenhagen (DK)

    DEFF Research Database (Denmark)

    Lützhøft, Hans-Christian Holten; Birch, Heidi; Eriksson, Eva;

    2011-01-01

    In the year 2000 the European Union implemented the European Water Framework Directive of which the overall aim is to maintain or obtain good ecological and chemical status of European near coastal waters, lakes, rivers, streams, groundwater as well as artificial water bodies as docks and canals...... (EU, 2000). It is also required to establish inventories of sources to pollution, to design and perform monitoring programs as well as to outline strategies to reduce emissions if the environmental quality standards are exceeded. The aim of this study was to compare chemical analysis performed...... on urban surface runoff originating from a well defined catchment of Copenhagen (Denmark) with an inventory of potential pollution sources for the same catchment. The selected catchment covers an area with roads, a shopping centre, a parking lot, office buildings, a gymnasium and some restaurants...

  19. Physico-Chemical Analysis of Selected Groundwater Samples of Inkollu Mandal, Prakasam District, Andhra Pradesh, India

    Directory of Open Access Journals (Sweden)

    G. Arun Kumar

    2015-04-01

    Full Text Available Physico-chemical parameters of groundwater quality based on Physic-chemical parameters at Inkollu mandal, Prakasam district, Andhra Pradesh, India have been taken up to evaluate its suitability for Drinking purpose. Nine ground water samples were collected from different places of Inkollu mandal of Prakasam district. The quality analysis has been made through the pH, EC, TDS, Total Hardness, Sodium, Potassium, Calcium, Magnesium, Chloride, Sulphate, Nitrate, Fluoride and Iron. By observing the results, it was shown that the parameters from the water samples were compared with WHO (World Health Organization and BIS (Bureau of Indian Standards, USPH (United state Public health for ground water .The results revealed that some parameters were in high concentration and quality of the potable water has deteriorated to a large extent at some sampling locations.

  20. Fault Diagnosis in Chemical Process Based on Self-organizing Map Integrated with Fisher Discriminant Analysis

    Institute of Scientific and Technical Information of China (English)

    CHEN Xinyi; YAN Xuefeng

    2013-01-01

    Fault diagnosis and monitoring are very important for complex chemical process.There are numerous methods that have been studied in this field,in which the effective visualization method is still challenging.In order to get a better visualization effect,a novel fault diagnosis method which combines self-organizing map (SOM) with Fisher discriminant analysis (FDA) is proposed.FDA can reduce the dimension of the data in terms of maximizing the separability of the classes.After feature extraction by FDA,SOM can distinguish the different states on the output map clearly and it can also be employed to monitor abnormal states.Tennessee Eastman (TE) process is employed to illustrate the fault diagnosis and monitoring performance of the proposed method.The result shows that the SOM integrated with FDA method is efficient and capable for real-time monitoring and fault diagnosis in complex chemical process.

  1. Reaction path analysis of sodium-water chemical reaction field using laser diagnostics

    International Nuclear Information System (INIS)

    In a sodium-cooled fast reactor (SFR), liquid sodium is used as a heat transfer fluid because of its excellent heat transport capability. On the other hand, it has strong chemical reactivity with water vapor. One of the design basis accidents of the SFR is the water leakage into the liquid sodium flow by a breach of heat transfer tubes. Therefore, the study on sodium-water chemical reactions is of importance for security reasons. This study aims to clarify the gas phase sodium-water reaction path and reaction products. Na, Na2, H2O, and reaction products in the counter-flow sodium-water reaction field were measured using laser diagnostics such as Raman scattering and photo-fragmentation. The main product in the sodium-water reaction was determined to be NaOH and its reaction path was discussed using Na-H2O elementally reaction analysis. (author)

  2. Instrumental neutron activation analysis applied to the chemical composition of steel

    International Nuclear Information System (INIS)

    In the technological application of steel, the knowledge of its chemical composition is of fundamental importance as it is directly related to various properties, such as, mechanical properties, corrosion resistance, temperability and others. Instrumental Neutron Activation Analysis, INAA, is an appropriate technique in the evaluation of the chemical composition of steel and other metallurgical materials due to the possibility of simultaneous determination of a great number of elements without the inconvenience of sample dissolution. Element determination is achieved with good accuracy and precision for major and minor constituents as well as for trace elements. In this paper, INAA was used in the determination of As, Co, Cu, Mn, Mo, V and W in steel and iron samples and in certified reference materials. The obtained accuracy and precision were less than 10% for most of the elements confirming the possibility of its use in the study of metallic samples and in the certification of new reference materials. (author)

  3. Analysis of solar chemical processes for hydrogen production from water splitting thermochemical cycles

    International Nuclear Information System (INIS)

    This paper presents a process analysis of ZnO/Zn, Fe3O4/FeO and Fe2O3/Fe3O4 thermochemical cycles as potential high efficiency, large scale and environmentally attractive routes to produce hydrogen by concentrated solar energy. Mass and energy balances allowed estimation of the efficiency of solar thermal energy to hydrogen conversion for current process data, accounting for chemical conversion limitations. Then, the process was optimized by taking into account possible improvements in chemical conversion and heat recoveries. Coupling of the thermochemical process with a solar tower plant providing concentrated solar energy was considered to scale up the system. An economic assessment gave a hydrogen production cost of 7.98$ kg-1 and 14.75$ kg-1 of H2 for, respectively a 55 MWth and 11 MWth solar tower plant operating 40 years

  4. Chemical contents in Lygeum spartum L. using instrumental neutron activation analysis

    Energy Technology Data Exchange (ETDEWEB)

    Nedjimi, Bouzid [Djelfa Univ. (Algeria). Lab. of Exploration and Valorization of Steppe Ecosystem; Beladel, Brahim [Djelfa Univ. (Algeria)

    2015-09-01

    The present investigation was conducted to determine the chemical contents of Lygeum spartum L. (Poaceae). Samples were analyzed in order to determine essential (Ca, K, Na, Fe, Co) and some potentially toxic elements (Eu, Sb, Tb) using instrumental neutron activation analysis (INAA). In general chemical element contents were in substantial amounts to meet adult sheep requirements. Potential intake of Ca, K, Zn, Co and Fe by ruminant weighing 50 kg BW consuming 2.0 kg per day DM was sufficient to satisfy their requirements. However, only Na level was still insufficient to meet the requirements for grazing ruminants. Potential toxic elements in this species were within the safety baseline of all the assayed elements recommended by NRC. Na supplementation would seem to be necessary in this zone, for optimum productivity of grazing animals.

  5. The geographical origin and chemical composition in phellinus mushrooms measured by instrumental neutron activation analysis

    International Nuclear Information System (INIS)

    In order to expand the utilization of phellinus mushrooms as a dietary supplement, we attempted to evaluate the chemical composition by measuring its inorganic elemental content with the aid of instrumental neutron activation analysis (INAA). Twenty seven phellinus mushrooms samples were collected from Korea, Cambodia, and Vietnam. A total of 28 elements were analyzed in the phellinus mushroom samples using the INAA. The concentrations of Ca, K, and Mg are much higher than those of other elements in phellinus mushroom samples. The sum of determined elemental concentration in Cambodia samples was about 2-6 times higher than those in Korea and Vietnam samples, respectively. Based on our measurement data, we attempted to discriminate the geographical origin using principal components analysis (PCA) and linear discriminant analysis (LDA). The geographical origins of all samples were clearly classified with correct classification rate of 100%. (author)

  6. Standard test methods for chemical, mass spectrometric, spectrochemical, nuclear, and radiochemical analysis of uranium hexafluoride

    CERN Document Server

    American Society for Testing and Materials. Philadelphia

    2011-01-01

    1.1 These test methods cover procedures for subsampling and for chemical, mass spectrometric, spectrochemical, nuclear, and radiochemical analysis of uranium hexafluoride UF6. Most of these test methods are in routine use to determine conformance to UF6 specifications in the Enrichment and Conversion Facilities. 1.2 The analytical procedures in this document appear in the following order: Note 1—Subcommittee C26.05 will confer with C26.02 concerning the renumbered section in Test Methods C761 to determine how concerns with renumbering these sections, as analytical methods are replaced with stand-alone analytical methods, are best addressed in subsequent publications. Sections Subsampling of Uranium Hexafluoride 7 - 10 Gravimetric Determination of Uranium 11 - 19 Titrimetric Determination of Uranium 20 Preparation of High-Purity U3O 8 21 Isotopic Analysis 22 Isotopic Analysis by Double-Standard Mass-Spectrometer Method 23 - 29 Determination of Hydrocarbons, Chlorocarbons, and Partially Substitut...

  7. Hydrogen Safety Project chemical analysis support task: Window ``C`` volatile organic analysis

    Energy Technology Data Exchange (ETDEWEB)

    Gillespie, B.M.; Stromatt, R.W.; Ross, G.A.; Hoope, E.A.

    1992-01-01

    This data package contains the results obtained by Pacific Northwest Laboratory (PNL) staff in the characterization of samples for the 101-SY Hydrogen Safety Project. The samples were submitted for analysis by Westinghouse Hanford Company (WHC) under the Technical Project Plan (TPP) 17667 and the Quality Assurance Plan MCS-027. They came from a core taken during Window ``C`` after the May 1991 gas release event. The analytical procedures required for analysis were defined in the Test Instructions (TI) prepared by the PNL 101-SY Analytical Chemistry Laboratory (ACL) Project Management Office in accordance with the TPP and the QA Plan. The requested analysis for these samples was volatile organic analysis. The quality control (QC) requirements for each sample are defined in the Test Instructions for each sample. The QC requirements outlined in the procedures and requested in the WHC statement of work were followed.

  8. Hydrogen Safety Project chemical analysis support task: Window C'' volatile organic analysis

    Energy Technology Data Exchange (ETDEWEB)

    Gillespie, B.M.; Stromatt, R.W.; Ross, G.A.; Hoope, E.A.

    1992-01-01

    This data package contains the results obtained by Pacific Northwest Laboratory (PNL) staff in the characterization of samples for the 101-SY Hydrogen Safety Project. The samples were submitted for analysis by Westinghouse Hanford Company (WHC) under the Technical Project Plan (TPP) 17667 and the Quality Assurance Plan MCS-027. They came from a core taken during Window C'' after the May 1991 gas release event. The analytical procedures required for analysis were defined in the Test Instructions (TI) prepared by the PNL 101-SY Analytical Chemistry Laboratory (ACL) Project Management Office in accordance with the TPP and the QA Plan. The requested analysis for these samples was volatile organic analysis. The quality control (QC) requirements for each sample are defined in the Test Instructions for each sample. The QC requirements outlined in the procedures and requested in the WHC statement of work were followed.

  9. Microfluidic electrochemical device and process for chemical imaging and electrochemical analysis at the electrode-liquid interface in-situ

    Science.gov (United States)

    Yu, Xiao-Ying; Liu, Bingwen; Yang, Li; Zhu, Zihua; Marshall, Matthew J.

    2016-03-01

    A microfluidic electrochemical device and process are detailed that provide chemical imaging and electrochemical analysis under vacuum at the surface of the electrode-sample or electrode-liquid interface in-situ. The electrochemical device allows investigation of various surface layers including diffuse layers at selected depths populated with, e.g., adsorbed molecules in which chemical transformation in electrolyte solutions occurs.

  10. Analysis of Thermal Desorption System for the Chemical Treatment of Old Storages of Oil Based Mud

    Directory of Open Access Journals (Sweden)

    Tanweer Hussain

    2013-04-01

    Full Text Available This paper presents an analysis for the chemical treatment of OBM (Oil Based Mud used in the drilling process in the oil and gas industry. The analysis is based on OBM stored at ENI (Italian National Energy gas fields at Bhit mount district Jamshoro since the last ten years that has been chemically and physically deteriorated. Characterization of various OBM samples was performed and these samples were processed in order to evaluate the best characteristics of the OBM for optimum treatment results. The OBM treatment process involves the separation of hazardous fluid (such as diesel or mineral oil from solids Due to the lean quality of the OBM, the dust separation process in the cyclone caused blockage in the cyclone. This paper suggests a remedial way by means of installation of a hammer stick in the cyclone dust collector to overcome cyclone blockage. The analysis is performed to compare the pressure drop and the dust collection efficiency in the cyclone with and without the hammer stick. The post-installation experimental results showed that hammer stick can improve the cyclone dust collection efficiency without blockage of the cyclone.

  11. Accuracy of chemical analysis of airborne particulates: results of an intercomparison exercise

    International Nuclear Information System (INIS)

    Since suitable standard reference materials for chemical analysis of airborne particulates are not available, an intercomparison exercise was carried out among 40 interested laboratories in order to evaluate the accuracy of various trace analysis techniques for this specific application. Six hundred grams of airborne particulates were collected from the inlet filters of the air conditioning installation of a hotel in the center of Milan. The sample was sieved to remove coarser particles, thoroughly mixed, and distributed in 1 to 5 gram aliquots. The homogeneity was checked by relative measurements carried out by three independent techniques. For 40 elements no inhomogeneity was found to exceed the analytical error, which was estimated to be approximately 10 percent. The data of the analytical exercise are being collected and evaluated. Results are available for 56 elements, but to date only 33 have been determined by more than one technique. Activation analysis, emission spectroscopy, atomic absorption, x-ray fluorescence and various wet chemical methods contributed to the intercomparison. No result was received from mass spectroscopic methods and, although analyses were specifically encouraged, very few results were received on the organic components. From a first approximate evaluation a good agreement was found for Al, Fe, Zn, Mn, Ca, Pb, Cl, S, Si, Ti, Mn, while for the other elements no definite conclusion can yet be drawn. An attempt will be made to interpret important cases of systematic errors, a few of which are already evident

  12. Chemical and Microbiological Analysis of Certain Water Sources and Industrial Wastewater Samples in Dakahlia Governorate

    International Nuclear Information System (INIS)

    The chemical analysis included quantitative measurement of electrical conductivity, alkalinity , hardness sulphate, ph, total dissolved solids, chloride, as well as dissolved oxygen was carried out. The microbiological examination for different water sources and industrial wastewater samples was also conducted. some of heavy metals, Co2+ Cu2+ Fe3+ and Mn2+ were determined in fresh water, while other metals, such as Cr6+ , Co2+ , Zn2+ and Ni2+ were measured in industrial wastewater. Results of the chemical analysis showed that all measured parameters were found within the limitation either national or international law, except some samples which showed higher values than the permissible limits for some measured parameters. The microbiological analysis exhibited presence of yeasts, fungi and bacteria. Most bacterial isolates were short rod, spore formers as well as coccoid shaped bacteria. The efficiency of water treatment process on the reduction of microbial load was also calculated. Regarding the pathogenic bacteria, data showed that neither water samples nor industrial wastewater contain pathogens when using specific cultivation media for the examination. Furthermore, data proved the possibility of recycling of the tested industrial wastewater on which some microorganisms can grow. Data showed that the percent of heavy metals removal can reach to more than 70% in some cases as a result to bacterial treatment of industrial wastewater

  13. Neutron activation analysis applied to the chemical composition of metallic materials

    International Nuclear Information System (INIS)

    The physical properties of metallic materials, such as mechanical properties, corrosion resistance and others are determined by their chemical composition, which influences the various steps of the production process and the economic value attained by the materials. Instrumental neutron activation analysis was used in this work to evaluate the chemical composition of iron, steel, silicon and ferrosilicon reference materials. The concentration of the elements As, Co, Cr, Mn, Mo, Ni, V and W were analyzed in the iron and steel samples whereas As, Br, Co, Cr, K, Eu, Fe, La, Mn, Mo, Na, Nd, U, Th, Sb, Sc, Sm, Tb, V, W and Yb were determined in silicon and ferrosilicon samples. Accuracy was assessed comparing obtained results to reference materials certified values. Results of about 10 % were achieved for most of the elements. Precision was assessed by replicate measurements, and the results of about 10 % were also achieved. Accuracy and precision results showed that the technique is suitable for the metallic materials composition analysis. Interferences of Cr and Mn in V, Fe and Co in Mn; Co in Fe and Cr in Ti were quantified and only the last one was critical to the analysis of the materials employed in this work. (author)

  14. Model analysis of influences of the high-temperature reactor on location shifting in chemical industry

    International Nuclear Information System (INIS)

    An analysis is presented of the influences of High-Temperature Reactor on probable location shifting of big chemical plants, in the future. This is done by a spatial location model, that includes an investigation on 116 industrial locations within the first six countries of Common Market. The results of a computerized program show differences in location qualities when furnished either with traditional or with nuclear energy systems. In addition to location factor energy some other important factors, as subventions, taxes, labour, and transport costs are analysed, and their influence on industrial location is quantified. (orig.)

  15. Improved Method for the Flow Injection Analysis of Chemical Oxygen Demand Using Silver Nitrate

    OpenAIRE

    Korenaga, Takashi; Ikatsu, Hisayoshi; Moriwake, Tosio; Takahashi, Teruo

    1980-01-01

    On the flow injection analysis (FIA) of chemical oxygendemand (COD), silver salt was added as an oxidation catalyst for COD substances and a masking agent for halide to improve operating conditions of the FIA apparatus. Both of a proper concentration of potassium permanganate solution and 6.0 % sulfuric acid solution containing 0.1 % silver nitrate are individually pumped up with respective flow rates of 0.51 ml min(-l) and merged into a carrier stream. A 20 μ1 of sample solution is injected ...

  16. Chemical composition analysis of ancient bricks and potteries by internal monostandard NAA

    International Nuclear Information System (INIS)

    The ko-based internal monostandard INAA (IM-INAA) method was used for the determination of major, minor and trace element concentrations in ancient bricks as well as potteries, collected from Buddhist (4th B.C. to 3rd A.D.) sites of in and around Vishakhapatnam district, Andhra Pradesh, India. Chemical composition analysis of these artifacts was carried out for the provenance study and also to find out possible correlations among the bricks and potteries. INAA is one of the best techniques used for the provenance study due to its advantageous properties like simultaneous multielement capability, negligible matrix effect, no spectral interference and inherent precision and accuracy

  17. Recent developments in methods of chemical analysis in investigations of firearm-related events.

    Science.gov (United States)

    Zeichner, Arie

    2003-08-01

    A review of recent (approximately the last ten years) developments in the methods used for chemical analysis in investigations of firearm-related events is provided. This review discusses:examination of gunshot (primer) residues (GSR) and gunpowder (propellant) residues on suspects and their clothing;detection of firearm imprints on the hands of suspects;identification of the bullet entry holes and estimation of shooting distance;linking weapons and/or fired ammunition to the gunshot entries, and estimation of the time since discharge. PMID:12811451

  18. Electrochemical metal speciation analysis of chemically heterogeneous samples: the outstanding features of stripping chronopotentiometry at scanned deposition potential

    NARCIS (Netherlands)

    Leeuwen, van H.P.; Town, R.M.

    2003-01-01

    The application of depletive stripping chronopotentiometry at scanned deposition potential (SSCP) to metal ion speciation analysis of chemically heterogeneous complex systems is described. In this electroanalytical stripping technique, metal which is accumulated in the electrode during the depositio

  19. Standard test methods for chemical, mass spectrometric, spectrochemical, nuclear, and radiochemical analysis of nuclear-grade plutonium metal

    CERN Document Server

    American Society for Testing and Materials. Philadelphia

    2004-01-01

    1.1 These test methods cover procedures for the chemical, mass spectrometric, spectrochemical, nuclear, and radiochemical analysis of nuclear-grade plutonium metal to determine compliance with specifications.

  20. 75 FR 56538 - Air Products and Chemicals, Inc.; Analysis of Proposed Agreement Containing Consent Orders to Aid...

    Science.gov (United States)

    2010-09-16

    ... Products and Chemicals, Inc.; Analysis of Proposed Agreement Containing Consent Orders to Aid Public... practices or unfair methods of competition. The attached Analysis to Aid Public Comment describes both the... period of thirty (30) days. The following Analysis to Aid Public Comment describes the terms of...

  1. CHEMKIN-III: A FORTRAN chemical kinetics package for the analysis of gas-phase chemical and plasma kinetics

    Energy Technology Data Exchange (ETDEWEB)

    Kee, R.J.; Rupley, F.M.; Meeks, E.; Miller, J.A.

    1996-05-01

    This document is the user`s manual for the third-generation CHEMKIN package. CHEMKIN is a software package whose purpose is to facilitate the formation, solution, and interpretation of problems involving elementary gas-phase chemical kinetics. It provides a flexible and powerful tool for incorporating complex chemical kinetics into simulations of fluid dynamics. The package consists of two major software components: an Interpreter and a Gas-Phase Subroutine Library. The Interpreter is a program that reads a symbolic description of an elementary, user-specified chemical reaction mechanism. One output from the Interpreter is a data file that forms a link to the Gas-Phase Subroutine Library. This library is a collection of about 100 highly modular FORTRAN subroutines that may be called to return information on equations of state, thermodynamic properties, and chemical production rates. CHEMKIN-III includes capabilities for treating multi-fluid plasma systems, that are not in thermal equilibrium. These new capabilities allow researchers to describe chemistry systems that are characterized by more than one temperature, in which reactions may depend on temperatures associated with different species; i.e. reactions may be driven by collisions with electrons, ions, or charge-neutral species. These new features have been implemented in such a way as to require little or no changes to CHEMKIN implementation for systems in thermal equilibrium, where all species share the same gas temperature. CHEMKIN-III now has the capability to handle weakly ionized plasma chemistry, especially for application related to advanced semiconductor processing.

  2. [Influence of ancient glass samples surface conditions on chemical composition analysis using portable XRF].

    Science.gov (United States)

    Liu, Song; Li, Qing-hui; Gan, Fu-xi

    2011-07-01

    Portable X-ray fluorescence analysis (PXRF) is one kind of surface analysis techniques, and the sample surface condition is an important factor that influences the quantitative analysis results. The ancient glass samples studied in the present paper were excavated from Xinjiang, Guangxi, Jiangsu provinces, and they belong to Na2O-CaO-SiO2, K2O-SiO2, and PbO-BaO-SiO2 system, respectively. Quantitative analysis results of weathered surface and inside of the ancient glass samples were compared. The concentration change of main fluxes in different parts of the samples was pointed out. Meanwhile, the authors studied the effect of distance between the sample and the reference plane, and curve shape of the sample on the quantitative results. The results obtained were calibrated by three methods, and the validity of these three methods was proved. Finally, the normalizing method was proved to be a better method for quantitative analysis of antiques. This paper also has guiding significance for chemical composition analysis of ancient jade samples using PXRF. PMID:21942060

  3. Chemical Imaging and Stable Isotope Analysis of Atmospheric Particles by NanoSIMS (Invited)

    Science.gov (United States)

    Sinha, B.; Harris, E. J.; Pöhlker, C.; Wiedemann, K. T.; van Pinxteren, D.; Tilgner, A.; Fomba, K. W.; Schneider, J.; Roth, A.; Gnauk, T.; Fahlbusch, B.; Mertes, S.; Lee, T.; Collett, J. L.; Shiraiwa, M.; Gunthe, S. S.; Smith, M.; Artaxo, P. P.; Gilles, M.; Kilcoyne, A. L.; Moffet, R.; Weigand, M.; Martin, S. T.; Poeschl, U.; Andreae, M. O.; Hoppe, P.; Herrmann, H.; Borrmann, S.

    2013-12-01

    Chemical imaging analysis of the internal distribution of chemical compounds by a combination of SEM-EDX, and NanoSIMS allows investigating the physico-chemical properties and isotopic composition of individual aerosol particles. Stable sulphur isotope analysis provides insight into the sources, sinks and oxidation pathways of SO2 in the environment. Oxidation by OH radicals, O3 and H2O2 enriches the heavier isotope in the product sulphate, whereas oxidation by transition metal ions (TMI), hypohalites and hypohalous acids depletes the heavier isotope in the product sulphate. The isotope fractionation during SO2 oxidation by stabilized Criegee Intermediate radicals is unknown. We studied the relationship between aerosol chemical composition and predominant sulphate formation pathways in continental clouds in Central Europe and during the wet season in the Amazon rain forest. Sulphate formation in continental clouds in Central Europe was studied during HCCT-2010, a lagrangian-type field experiment, during which an orographic cloud was used as a natural flow-through reactor to study in-cloud aerosol processing (Harris et al. 2013). Sulphur isotopic compositions in SO2 and H2SO4 gas and particulate sulphate were measured and changes in the sulphur isotope composition of SO2 between the upwind and downwind measurement sites were used to determine the dominant SO2 chemical removal process occurring in the cloud. Changes in the isotopic composition of particulate sulphate revealed that transition metal catalysis pathway was the dominant SO2 oxidation pathway. This reaction occurred primarily on coarse mineral dust particles. Thus, sulphate produced due to in-cloud SO2 oxidation is removed relatively quickly from the atmosphere and has a minor climatic effect. The aerosol samples from the Amazonian rainforest, a pristine tropical environment, were collected during the rainy season. The samples were found to be dominated by SOA particles in the fine mode and primary

  4. Texture Profile Analysis of Sliced Cheese in relation to Chemical Composition and Storage Temperature

    Directory of Open Access Journals (Sweden)

    Yuanrong Zheng

    2016-01-01

    Full Text Available The quantitative relationships among chemical composition, storage temperature, and texture of cheese were not fully understood. In this study, the effects of composition and temperature on textural properties of eight common varieties of sliced cheese were examined. The textural properties of sliced cheeses, including firmness, cohesiveness, adhesiveness, springiness, chewiness, and resilience, were measured by texture profile analysis after storage at 4 and 25°C for 4 h. Multivariate logistic regression models were established to describe the quantitative relationships of textural properties (dependent variables to chemical composition and storage temperature (independent variables of sliced cheeses. Results showed that protein, fat, moisture, and sodium chloride contents as well as storage temperature significantly affected the texture of sliced cheeses (P<0.05. In particular, fat in the dry matter and moisture in the nonfat substances were negatively correlated with firmness of sliced cheeses (P<0.05. As storage temperature rose from 4 to 25°C, the average values of firmness, chewiness, and resilience substantially declined by 42%, 45%, and 17%, respectively (P<0.05. This study provided reference data for adjusting chemical composition and storage temperature of common cheese products to obtain favorable texture for Chinese consumers, which thereby facilitated the localization of cheese industry in Chinese market.

  5. Advancement in the chemical analysis and quality control of flavonoid in Ginkgo biloba.

    Science.gov (United States)

    Liu, Xin-Guang; Wu, Si-Qi; Li, Ping; Yang, Hua

    2015-09-10

    Flavonoids are the main active constituents in Ginkgo biloba L., which have been suggested to have broad-spectrum free-radical scavenging activities. This review summarizes the recent advances in the chemical analysis of the flavonoids in G. biloba and its finished products (from 2009 to 2014), including chemical composition, sample preparation, separation, detection and different quality criteria. More than 70 kinds of flavonoids have been identified in this plant. In this review, various analytical approaches as well as their chromatographic conditions have been described, and their advantages/disadvantages are also compared. Quantitative analyses of Ginkgo flavonoids applied by most pharmacopeias start with an acidic hydrolysis followed by determination of the resulting aglycones using HPLC. But increasing direct assay of individual flavonol glycosides found that many adulterated products were still qualified by the present tests. To obtain an authentic and applicable analytical approach for quality evaluation of Ginkgo and its finished products, related suggestions and opinions in the recent publications are mainly discussed in this review. This discussion on chemical analyses of Ginkgo flavonoids will also be found as a significant guide for widely varied natural flavonoids.

  6. Human exploration of near earth asteroids: Mission analysis for chemical and electric propulsion

    Science.gov (United States)

    Herman, Jonathan F. C.; Zimmer, Aline K.; Reijneveld, Johannes P. J.; Dunlop, Kathryn L.; Takahashi, Yu; Tardivel, Simon; Scheeres, Daniel J.

    2014-11-01

    This paper presents a mission analysis comparison of human missions to asteroids using two distinct architectures. The objective is to determine if either architecture can reduce launch mass with respect to the other, while not sacrificing other performance metrics such as mission duration. One architecture relies on chemical propulsion, the traditional workhorse of space exploration. The second combines chemical and electric propulsion into a hybrid architecture that attempts to utilize the strengths of each, namely the short flight times of chemical propulsion and the propellant efficiency of electric propulsion. The architectures are thoroughly detailed, and accessibility of the known asteroid population is determined for both. The most accessible asteroids are discussed in detail. Aspects such as mission abort scenarios and vehicle reusability are also discussed. Ultimately, it is determined that launch mass can be greatly reduced with the hybrid architecture, without a notable increase in mission duration. This demonstrates that significant performance improvements can be introduced to the next step of human space exploration with realistic electric propulsion system capabilities. This leads to immediate cost savings for human exploration and simultaneously opens a path of technology development that leads to technologies enabling access to even further destinations in the future.

  7. Quantitative assessment of chemical artefacts produced by propionylation of histones prior to mass spectrometry analysis.

    Science.gov (United States)

    Soldi, Monica; Cuomo, Alessandro; Bonaldi, Tiziana

    2016-07-01

    Histone PTMs play a crucial role in regulating chromatin structure and function, with impact on gene expression. MS is nowadays widely applied to study histone PTMs systematically. Because histones are rich in arginine and lysine, classical shot-gun approaches based on trypsin digestion are typically not employed for histone modifications mapping. Instead, different protocols of chemical derivatization of lysines in combination with trypsin have been implemented to obtain "Arg-C like" digestion products that are more suitable for LC-MS/MS analysis. Although widespread, these strategies have been recently described to cause various side reactions that result in chemical modifications prone to be misinterpreted as native histone marks. These artefacts can also interfere with the quantification process, causing errors in histone PTMs profiling. The work of Paternoster V. et al. is a quantitative assessment of methyl-esterification and other side reactions occurring on histones after chemical derivatization of lysines with propionic anhydride [Proteomics 2016, 16, 2059-2063]. The authors estimate the effect of different solvents, incubation times, and pH on the extent of these side reactions. The results collected indicate that the replacement of methanol with isopropanol or ACN not only blocks methyl-esterification, but also significantly reduces other undesired unspecific reactions. Carefully titrating the pH after propionic anhydride addition is another way to keep methyl-esterification under control. Overall, the authors describe a set of experimental conditions that allow reducing the generation of various artefacts during histone propionylation. PMID:27373704

  8. Summer 2012 Testing and Analysis of the Chemical Mixture Methodology -- Part I

    Energy Technology Data Exchange (ETDEWEB)

    Glantz, Clifford S.; Yu, Xiao-Ying; Coggin, Rebekah L.; Ponder, Lashaundra A.; Booth, Alexander E.; Petrocchi, Achille J.; Horn, Sarah M.; Yao, Juan

    2012-07-01

    This report presents the key findings made by the Chemical Mixture Methodology (CMM) project team during the first stage of their summer 2012 testing and analysis of the CMM. The study focused on answering the following questions: o What is the percentage of the chemicals in the CMM Rev 27 database associated with each Health Code Number (HCN)? How does this result influence the relative importance of acute HCNs and chronic HCNs in the CMM data set? o What is the benefit of using the HCN-based approach? Which Modes of Action and Target Organ Effects tend to be important in determining the HCN-based Hazard Index (HI) for a chemical mixture? o What are some of the potential issues associated with the current HCN-based approach? What are the opportunities for improving the performance and/or technical defensibility of the HCN-based approach? How would those improvements increase the benefit of using the HCN-based approach? o What is the Target Organ System Effect approach and how can it be used to improve upon the current HCN-based approach? How does the benefits users would derive from using the Target Organ System Approach compare to the benefits available from the current HCN-based approach?

  9. A large scale analysis of information-theoretic network complexity measures using chemical structures.

    Directory of Open Access Journals (Sweden)

    Matthias Dehmer

    Full Text Available This paper aims to investigate information-theoretic network complexity measures which have already been intensely used in mathematical- and medicinal chemistry including drug design. Numerous such measures have been developed so far but many of them lack a meaningful interpretation, e.g., we want to examine which kind of structural information they detect. Therefore, our main contribution is to shed light on the relatedness between some selected information measures for graphs by performing a large scale analysis using chemical networks. Starting from several sets containing real and synthetic chemical structures represented by graphs, we study the relatedness between a classical (partition-based complexity measure called the topological information content of a graph and some others inferred by a different paradigm leading to partition-independent measures. Moreover, we evaluate the uniqueness of network complexity measures numerically. Generally, a high uniqueness is an important and desirable property when designing novel topological descriptors having the potential to be applied to large chemical databases.

  10. Chemical analysis of CH stars - II: atmospheric parameters and elemental abundances

    CERN Document Server

    Karinkuzhi, Drisya

    2014-01-01

    We present detailed chemical analyses for a sample of twelve stars selected from the CH star catalogue of Bartkevicius (1996). The sample includes two confirmed binaries, four objects that are known to show radial velocity variations and the rest with no information on the binary status. A primary objective is to examine if all these objects exhibit chemical abundances characteristics of CH stars, based on detailed chemical composition study using high resolution spectra. We have used high resolution (R ~ 42000) spectra from the ELODIE archive. These spectra cover 3900 to 6800 Angstrom in the wavelength range. We have estimated the stellar atmospheric parameters, the effective temperature Teff, the surface gravity log g, and metallicity [Fe/H] from LTE analysis using model atmospheres. Estimated temperatures of these objects cover a wide range from 4200 K to 6640 K, the surface gravity from 0.6 to 4.3 and metallicity from -0.13 to -1.5. We report updates on elemental abundances for several heavy elements, Sr,...

  11. Chemical analysis of groundwater of Nathnagar Block under Bhagalpur District, Bihar (India).

    Science.gov (United States)

    Singh, Amrita; Choudhary, Sunil K

    2011-10-01

    The chemical analysis of groundwater samples from hundred handpumps in five villages of the Nathnagar Block under Bhagalpur District, Bihar, India indicates that the water samples in the area were slightly alkaline and the concentration of total hardness and heavy metal like arsenic were above the drinking water specifications as prescribed by World Health Organization (1999) and ISI (2003); whereas other chemical parameters were well within the permissible limit. The results of the present study suggest that the groundwater sources under investigation were suitable for domestic purposes including drinking except for arsenic. The concentration of arsenic in most of the handpumps analyzed was high, and that might be attributed to the excessive withdrawal of the groundwater and changes in the geo-chemical environment of the Ganga river. Moreover, the Ganga River System itself carries high sediment bed loads which contain several trace elements, including arsenic. Some effective measures like rainwater harvesting and artificial recharge techniques are urgently required and suggested for water quality management in this region. PMID:23505826

  12. Standard test methods for chemical, mass spectrometric, and spectrochemical analysis of nuclear-grade boron carbide

    CERN Document Server

    American Society for Testing and Materials. Philadelphia

    2004-01-01

    1.1 These test methods cover procedures for the chemical, mass spectrometric, and spectrochemical analysis of nuclear-grade boron carbide powder and pellets to determine compliance with specifications. 1.2 The analytical procedures appear in the following order: Sections Total Carbon by Combustion and Gravimetry 7-17 Total Boron by Titrimetry 18-28 Isotopic Composition by Mass Spectrometry 29-38 Chloride and Fluoride Separation by Pyrohydrolysis 39-45 Chloride by Constant-Current Coulometry 46-54 Fluoride by Ion-Selective Electrode 55-63 Water by Constant-Voltage Coulometry 64-72 Impurities by Spectrochemical Analysis 73-81 Soluble Boron by Titrimetry 82-95 Soluble Carbon by a Manometric Measurement 96-105 Metallic Impurities by a Direct Reader Spectrometric Method 106-114

  13. Application of Image Analysis Based on SEM and Chemical Mapping on PC Mortars under Sulfate Attack

    Institute of Scientific and Technical Information of China (English)

    YU Cheng; SUN Wei; Scrivener Karen

    2014-01-01

    The degradation mechanisms of cementitious materials exposed to sulfate solutions have been controversial, despite considerable research. In this paper, two methodologies of image analysis based on scanning electron microscope and chemical mapping are used to analyse Portland cement mortars exposed to sodium sulfate solution. The effects of sulfate concentration in solution and water to cement ratio of mortar, which are considered as the most sensitive factors to sulfate attack, are investigated respectively by comparing the macro expansion with microstructure analysis. It is found that the sulfate concentration in pore solution, expressed as sulfate content in C-S-H, plays a critical role on the supersaturation with respect to ettringite and so on the expansion force generated.

  14. An aligned mixture probabilistic principal component analysis for fault detection of multimode chemical processes☆

    Institute of Scientific and Technical Information of China (English)

    Yawei Yang; Yuxin Ma; Bing Song; Hongbo Shi

    2015-01-01

    A novel approach named aligned mixture probabilistic principal component analysis (AMPPCA) is proposed in this study for fault detection of multimode chemical processes. In order to exploit within-mode correlations, the AMPPCA algorithm first estimates a statistical description for each operating mode by applying mixture prob-abilistic principal component analysis (MPPCA). As a comparison, the combined MPPCA is employed where mon-itoring results are softly integrated according to posterior probabilities of the test sample in each local model. For exploiting the cross-mode correlations, which may be useful but are inadvertently neglected due to separately held monitoring approaches, a global monitoring model is constructed by aligning al local models together. In this way, both within-mode and cross-mode correlations are preserved in this integrated space. Finally, the utility and feasibility of AMPPCA are demonstrated through a non-isothermal continuous stirred tank reactor and the TE benchmark process.

  15. Systems Analysis of Protein Fatty Acylation in Herpes Simplex Virus-Infected Cells Using Chemical Proteomics

    Science.gov (United States)

    Serwa, Remigiusz A.; Abaitua, Fernando; Krause, Eberhard; Tate, Edward W.; O’Hare, Peter

    2015-01-01

    Summary Protein fatty acylation regulates diverse aspects of cellular function and organization and plays a key role in host immune responses to infection. Acylation also modulates the function and localization of virus-encoded proteins. Here, we employ chemical proteomics tools, bio-orthogonal probes, and capture reagents to study myristoylation and palmitoylation during infection with herpes simplex virus (HSV). Using in-gel fluorescence imaging and quantitative mass spectrometry, we demonstrate a generalized reduction in myristoylation of host proteins, whereas palmitoylation of host proteins, including regulators of interferon and tetraspanin family proteins, was selectively repressed. Furthermore, we found that a significant fraction of the viral proteome undergoes palmitoylation; we identified a number of virus membrane glycoproteins, structural proteins, and kinases. Taken together, our results provide broad oversight of protein acylation during HSV infection, a roadmap for similar analysis in other systems, and a resource with which to pursue specific analysis of systems and functions. PMID:26256475

  16. Econophysics and bio-chemical engineering thermodynamics: The exergetic analysis of a municipality

    Science.gov (United States)

    Lucia, Umberto

    2016-11-01

    Exergy is a fundamental quantity because it allows us to obtain information on the useful work obtainable in a process. The analyses of irreversibility are important not only in the design and development of the industrial devices, but also in fundamental thermodynamics and in the socio-economic analysis of municipality. Consequently, the link between entropy and exergy is discussed in order to link econophysics to the bio-chemical engineering thermodynamics. Last, this link holds to the fundamental role of fluxes and to the exergy exchanged in the interaction between the system and its environment. The result consists in a thermodynamic approach to the analysis of the unavailability of the economic, productive or social systems. The unavailability is what the system cannot use in relation to its internal processes. This quantity result is interesting also as a support to public manager for economic decisions. Here, the Alessandria Municipality is analyzed in order to highlight the application of the theoretical results.

  17. Chemical Analysis of the Herbal Medicine Salviae miltiorrhizae Radix et Rhizoma (Danshen

    Directory of Open Access Journals (Sweden)

    Hanqing Pang

    2016-01-01

    Full Text Available Radix Salviae miltiorrhizae et Rhizoma, known as Danshen in China, is one of the most popular traditional Chinese medicines. Recently, there has been increasing scientific attention on Danshen for its remarkable bioactivities, such as promoting blood circulation, removing blood stasis, and clearing away heat. This review summarized the advances in chemical analysis of Danshen and its preparations since 2009. Representative established methods were reviewed, including spectroscopy, thin layer chromatography, gas chromatography, liquid chromatography (LC, liquid chromatography-mass spectrometry (LC-MS, capillary electrophoresis, electrochemistry, and bioanalysis. Especially the analysis of polysaccharides in Danshen was discussed for the first time. Some proposals were also put forward to benefit quality control of Danshen.

  18. Characterization of Maturity Level in Laying Hen Manure by Chemical and Thermogravimetric Analysis

    Directory of Open Access Journals (Sweden)

    Alice Dall’Ara

    2008-01-01

    Full Text Available This study aims at investigating maturity levels in manure from laying hens in order to encourage its agronomic re-utilization. In fact the use of unstable/insufficiently mature manure could potentially damage both soils and crops. Effective, easy to reproduce methods are needed in order to assess bio-stabilisation and maturity levels, particularly for biomass that has not undergone conventional composting. This study compares samples of caged, laying hen manure, an organic matter rich in nutrients, N and P and devoid of litter or bulking agents, at different levels of maturation. Both chemical (dry matter, ashes, carbon and its fractioning, total and ammoniacal nitrogen and physical methods, such as thermogravimetry, were used to characterize them. Such physical methods do introduce any sample modification and shorten the analysis time. From a statistical point of view, chemical methods are effective only in distinguishing among different drying methods connected with manure management systems. Only thermogravimetric analysis can identify mature samples by means of total mass loss in the range RT- 900°C, mass loss in the range 350-425°C and energy release at 500°C. In addition, thermogravimetric profiles could be used to define a fingerprint for this kind of biomass.

  19. High-throughput peptide mass fingerprinting and protein macroarray analysis using chemical printing strategies

    International Nuclear Information System (INIS)

    We describe a 'chemical printer' that uses piezoelectric pulsing for rapid and accurate microdispensing of picolitre volumes of fluid for proteomic analysis of 'protein macroarrays'. Unlike positive transfer and pin transfer systems, our printer dispenses fluid in a non-contact process that ensures that the fluid source cannot be contaminated by substrate during a printing event. We demonstrate automated delivery of enzyme and matrix solutions for on-membrane protein digestion and subsequent peptide mass fingerprinting (pmf) analysis directly from the membrane surface using matrix-assisted laser-desorption/ionization time-of-flight (MALDI-TOF) mass spectrometry (MS). This approach bypasses the more commonly used multi-step procedures, thereby permitting a more rapid procedure for protein identification. We also highlight the advantage of printing different chemistries onto an individual protein spot for multiple microscale analyses. This ability is particularly useful when detailed characterisation of rare and valuable sample is required. Using a combination of PNGase F and trypsin we have mapped sites of N-glycosylation using on-membrane digestion strategies. We also demonstrate the ability to print multiple serum samples in a micro-ELISA format and rapidly screen a protein macroarray of human blood plasma for pathogen-derived antigens. We anticipate that the 'chemical printer' will be a major component of proteomic platforms for high-throughput protein identification and characterisation with widespread applications in biomedical and diagnostic discovery

  20. Refractometry and interferometry in chemical analysis; Refractometrie et interferometrie en analyse chimique

    Energy Technology Data Exchange (ETDEWEB)

    Veret, C. [Faculte des Sciences de Paris, 75 (France)

    2000-03-01

    In vacuum, an electromagnetic radiation is propagated at a constant velocity. But, when it has to pass through a physical medium, it is submitted to different interactions (for instance: absorption, diffusion, refraction, polarization, dispersion, fluorescence) which lead to a modification of its propagation. In the frequency ranges of the radiation for which the absorption is not very important, the modifications of the propagation velocity of a radiation can bring data on the nature and/or the physical conditions (pressure, temperature) of a medium, whatever its state be: gas, liquid or solid. Thus, the absolute refractive index of a medium in relation to vacuum is defined as the ratio c/v of the propagation velocity c of a monochromatic electromagnetic radiation in vacuum at its velocity v in this medium. The photonic refractometry (field of ultraviolet, visible and infrared radiations) is the set of the measure techniques of the refractive indexes having a role in chemical analysis. The refractometry measures can only be applied to media which are optically transparent. After having described these techniques, the author presents their uses in chemical analysis. (O.M.)

  1. Isolation and chemical analysis of nanoparticles from English ivy (Hedera helix L.)

    Energy Technology Data Exchange (ETDEWEB)

    Lenaghan, Scott C [University of Tennessee, Knoxville (UTK); Burris, Jason N [ORNL; Chourey, Karuna [ORNL; Huang, Yujian [University of Tennessee, Knoxville (UTK); Lady, Belinda [University of Tennessee, Knoxville (UTK); Sharma, Ritin [ORNL; Pan, Chongle [ORNL; Lejeune, Zorabel M [ORNL; Foister, Shane [ORNL; Hettich, Robert {Bob} L [ORNL; StewartJr., C neal [University of Tennessee, Knoxville (UTK); Zhang, Mingjun [ORNL

    2013-01-01

    It was discovered that adventitious roots of English ivy secreted a high strength adhesive containing uniform nanoparticles. These nanoparticles were hypothesized to be organic in nature. Subsequent studies have revealed several applications for these nanoparticles, but their chemical composition remained unknown. Here, we describe an isolation procedure to obtain gram quantities of ivy nanoparticles from adventitious roots. In addition, ultraviolet/visible (UV/Vis) spectroscopy, inductively coupled plasma mass spectrometry (ICP-MS), elemental analysis, fourier transform infrared spectroscopy (FTIR), and gel electrophoresis were conducted to identify the chemical nature of the ivy nanoparticles. Based on this comprehensive analysis, we conclude that the ivy nanoparticles are proteinaceous consisting of 51.77% carbon, 4.72% nitrogen, and 0.32% sulfur, without the presence of metals. Liquid chromatography tandem mass spectrometry (LC-MS/MS) based protein profiling revealed the presence of at least 6 proteins, including heat shock proteins and other large molecular weight proteins. Identification of these protein candidates will facilitate gene discovery and bioproduction of ivy nanoparticles.

  2. Backside versus frontside advanced chemical analysis of high-k/metal gate stacks

    Energy Technology Data Exchange (ETDEWEB)

    Martinez, E., E-mail: eugenie.martinez@cea.fr [Univ Grenoble Alpes, F-38000 Grenoble (France); CEA, LETI, MINATEC Campus, F-38054 Grenoble (France); Saidi, B. [STMicroelectronics, 850 rue Jean Monnet, 38926 Rousset Cedex, Crolles (France); Veillerot, M. [Univ Grenoble Alpes, F-38000 Grenoble (France); CEA, LETI, MINATEC Campus, F-38054 Grenoble (France); Caubet, P. [STMicroelectronics, 850 rue Jean Monnet, 38926 Rousset Cedex, Crolles (France); Fabbri, J-M. [Univ Grenoble Alpes, F-38000 Grenoble (France); CEA, LETI, MINATEC Campus, F-38054 Grenoble (France); Piallat, F. [STMicroelectronics, 850 rue Jean Monnet, 38926 Rousset Cedex, Crolles (France); Gassilloud, R. [Univ Grenoble Alpes, F-38000 Grenoble (France); CEA, LETI, MINATEC Campus, F-38054 Grenoble (France); Schamm-Chardon, S. [CEMES-CNRS et Université de Toulouse, 29 rue Jeanne Marvig, 31055 Toulouse (France)

    2015-08-15

    Highlights: • The backside approach is a promising solution for advanced chemical characterization of future MOSFETs. • Frontside ToF-SIMS and Auger depth profiles are affected by cumulative mixing effects and thus not relevant for analyzing ultra-thin layers. • Higher in-depth resolution is possible in the backside approach for Auger and ToF-SIMS depth profiling. • Backside depth profiling allows revealing ultra-thin layers and elemental in-depth redistribution inside high-k/metal gate stacks. • Backside XPS allows preserving the full metal gate, thus enabling the analysis of real technological samples. - Abstract: Downscaling of transistors beyond the 14 nm technological node requires the implementation of new architectures and materials. Advanced characterization methods are needed to gain information about the chemical composition of buried layers and interfaces. An effective approach based on backside analysis is presented here. X-ray photoelectron spectroscopy, Auger depth profiling and time-of-flight secondary ions mass spectrometry are combined to investigate inter-diffusion phenomena. To highlight improvements related to the backside method, backside and frontside analyses are compared. Critical information regarding nitrogen, oxygen and aluminium redistribution inside the gate stacks is obtained only in the backside configuration.

  3. Extractive Atmospheric Pressure Photoionization (EAPPI) Mass Spectrometry: Rapid Analysis of Chemicals in Complex Matrices

    Science.gov (United States)

    Liu, Chengyuan; Yang, Jiuzhong; Wang, Jian; Hu, Yonghua; Zhao, Wan; Zhou, Zhongyue; Qi, Fei; Pan, Yang

    2016-10-01

    Extractive atmospheric pressure photoionization (EAPPI) mass spectrometry was designed for rapid qualitative and quantitative analysis of chemicals in complex matrices. In this method, an ultrasonic nebulization system was applied to sample extraction, nebulization, and vaporization. Mixed with a gaseous dopant, vaporized analytes were ionized through ambient photon-induced ion-molecule reactions, and were mass-analyzed by a high resolution time-of-flight mass spectrometer (TOF-MS). After careful optimization and testing with pure sample solution, EAPPI was successfully applied to the fast screening of capsules, soil, natural products, and viscous compounds. Analysis was completed within a few seconds without the need for preseparation. Moreover, the quantification capability of EAPPI for matrices was evaluated by analyzing six polycyclic aromatic hydrocarbons (PAHs) in soil. The correlation coefficients ( R 2 ) for standard curves of all six PAHs were above 0.99, and the detection limits were in the range of 0.16-0.34 ng/mg. In addition, EAPPI could also be used to monitor organic chemical reactions in real time.

  4. PHYSICO-CHEMICAL ANALYSIS OF SELECTED GROUND WATER SAMPLES OF RURAL AREAS OF JAIPUR, RAJASTHAN

    Directory of Open Access Journals (Sweden)

    Priyanka Dhingra

    2014-12-01

    Full Text Available The aim of present study was to assess the status of the groundwater in rural areas of Jaipur city. People on globe are under tremendous threat due to undesired changes in the physical, chemical and biological characteristics of air, water and soil. Due to increased population, urbanization, industrialization, use of fertilizers water is highly polluted with different harmful contaminants Natural water resources are being contaminated due to weathering of rocks and leaching of soil, mining processing etc. It is necessary that quality of drinking water should be checked at regular time interval to prevent various water born diseases. In present analysis physico-chemical parameter of drinking water viz. pH, hardness, TDS, residual chlorine, dissolved oxygen, electrical conductivity, Free CO2 have been analyzed. Drinking water quality of 8 villages of Amber District Jaipur, Rajasthan was analyzed to identify the nature and quality of water. The drinking water samples were collected in clean polythene one liter cans and subjected for analysis in laboratory. The main objective of the present paper is to aware people of concerned area about the water quality and concerned health hazards.

  5. Risk analysis in the chemical industry; Analisis de riesgos en la industria quimica

    Energy Technology Data Exchange (ETDEWEB)

    Rea Soto, Rogelio; Sandoval Valenzuela, Salvador [Instituto de Investigaciones Electricas, Temixco, Morelos (Mexico)

    2000-07-01

    The Instituto de Investigaciones Electricas has a group of risk analysis (GAR), specialized in the most advanced methodologies to apply them in diverse industries of the productive sector, such as the nuclear, the oil and the chemical industries. In this work the integrated methodology that the GAR uses to make risk analysis in the chemical and oil industries is described. These analyses have as an objective to make a meticulous evaluation of the system design, the operation practices, the maintenance and inspection policies and the emergency plans. [Spanish] El Instituto de Investigaciones Electricas cuenta con un grupo de analisis de riesgo (GAR), especializado en las metodologias mas avanzadas para aplicarlas en diversas industrias del sector productivo, como lo son la nuclear, la petrolera y la quimica. En este trabajo se describe la metodologia integrada que el GAR utiliza para realizar analisis de riesgos en las industrias quimica y petrolera. Estos analisis tienen como objetivo realizar una minuciosa evaluacion del diseno del sistema, las practicas de operacion, las politicas de mantenimiento e inspeccion y los planes de emergencia.

  6. Thermal Analysis and Investigation of NiO-Based Oxygen Carriers for Chemical-Looping Combustion

    Energy Technology Data Exchange (ETDEWEB)

    Jerndal, Erik, e-mail: erik.jerndal@chalmers.se

    2009-03-15

    Capture and storage of CO{sub 2} can be used to reduce greenhouse gas emissions from combustion of fossil fuels. Chemical-looping combustion is a two-step combustion process where CO{sub 2} is obtained in a separate stream, ready for compression and storage. The technology uses circulating oxygen carriers to transfer oxygen from an air reactor to a fuel reactor, thus avoiding an energy consuming gas separation unit. A thermal analysis of the process using a large number of possible oxygen carriers was performed by simulating chemical reactions. Based on the ability of the oxygen carriers to convert different gaseous fuels, stability in air and melting temperature some metal oxides based on Ni, Cu, Fe, Mn, Co, W and sulphates of Ba, Sr and Ca showed good thermodynamic properties and could be feasible as oxygen carriers. The promising systems were investigated further with respect to temperature changes in the fuel reactor as well as possible formation of carbon, sulphides and sulphates which may deactivate the oxygen carriers. Oxygen carriers of NiO, supported by NiAl{sub 2}O{sub 4}, were prepared and investigated experimentally with respect to parameters important for chemical-looping combustion. These oxygen carriers were based on commercially available raw materials in contrast to most of the previously tested oxygen carriers, which have been prepared from pure chemicals. Further, it was investigated if spray-drying, which is a production method suitable for large-scale particle preparation, can be used to produce high performing oxygen carriers instead of the small-scale freeze-granulation method. Generally, materials prepared from commercially available raw material showed high reactivity with methane and oxygen. Oxygen carriers prepared by spray-drying, displayed a remarkable similarity when compared to oxygen carriers prepared from the same starting material by freeze-granulation, both regarding physical properties and reactivity. Further, the up-scaling of

  7. Two-dimensional dopant analysis in silicon using chemical etching and transmission electron microscopy

    Science.gov (United States)

    Neogi, Suneeta Shamanna

    The purpose of this research has been to develop a methodologoy to map two-dimensional dopant distributions in silicon and investigate the factors that influence the interpretation of the results. The analysis exploits the image contrast obtained by transmission electron microscopy (TEM) using cross-section specimens which have undergone selective chemical etching. The appearance of iso-thickness contours in a selectively etched TEM sample must represent iso-concentration contours when imaged under constant diffraction conditions. The application of this technique is two-fold: (1) to establish a physical metrology of semiconductor devices for the purpose of research and development efforts that impact on future nodes outlined in the semiconductor roadmap and (2) to provide physical data for validation of simulation tools in technology computer aided design (TCAD). The research involves an investigation into the selective removal of doped regions for both test and device structures, followed by an analysis to obtain two-dimensional (2-D) dopant profiles. The critical issues which arise in the development of a methodology to profile dopant distributions and which are addressed in this investigation are, wedge technique versus conventional dimple and ion-mill procedures for thin-film preparation, thin-film versus bulk chemical etching, data acquisition using TEM and choice of diffraction conditions, sensitivity in terms of the etch detection limit, resolution influenced by the effective extinction length of the operating reflection, digital image processing to extract profiles from thickness contours, calibration of the 2-D profiles using a one-dimensional (1-D) calibrator and role of structure/dopant interactions such as stress, interfaces and point defects in test structures and real device structures containing additional processing sequences. Selective chemical etching in combination with TEM has the sensitivity, resolution and reproducibility required to be used

  8. Chemical fingerprint analysis of Gentianae Radix et Rhizoma by high-performance liquid chromatography

    Directory of Open Access Journals (Sweden)

    Baozhong Duan

    2012-02-01

    Full Text Available Gentianae Radix et Rhizoma (also called “Longdan” in Chinese is commonly used for eliminating damp-heat and quenching the fire of liver and gall bladder in traditional Chinese medicine. In this study, a novel and reliable method using high-performance liquid chromatography (HPLC was developed both for quantitative analysis of four bioactive compounds (loganic acid, swertiamarin, gentiopicroside and sweroside and chemical fingerprint analysis of “Longdan”. In quantitative analysis, four compounds showed good regressions (R2>0.9987 within the test ranges and the recovery of the method was in the range 97.61−102.49%. In fingerprint analysis, ten characteristic peaks were selected to evaluate the similarities of the crude drugs, and the HPLC chromatograms of twenty samples from different regions of China showed similar patterns. The results demonstrated that the combination of the quantitative and chromatographic fingerprint analyses offered an efficient way to evaluate the quality consistency of Gentianae Radix et Rhizoma.

  9. Application of Time-series Analysis in Control of Chemical Composition of Grey Cast Iron

    Directory of Open Access Journals (Sweden)

    M. Perzyk

    2012-12-01

    Full Text Available The aim of the paper was an attempt at applying the time-series analysis to the control of the melting process of grey cast iron inproduction conditions. The production data were collected in one of Polish foundries in the form of spectrometer printouts. The quality of the alloy was controlled by its chemical composition in about 0.5 hour time intervals. The procedure of preparation of the industrial data is presented, including OCR-based method of transformation to the electronic numerical format as well as generation of records related to particular weekdays. The computations for time-series analysis were made using the author’s own software having a wide range of capabilities, including detection of important periodicity in data as well as regression modeling of the residual data, i.e. the values obtained after subtraction of general trend, trend of variability amplitude and the periodical component. The most interesting results of the analysis include: significant 2-measurements periodicity of percentages of all components, significance 7-day periodicity of silicon content measured at the end of a day and the relatively good prediction accuracy obtained without modeling of residual data for various types ofexpected values. Some practical conclusions have been formulated, related to possible improvements in the melting process controlprocedures as well as more general tips concerning applications of time-series analysis in foundry production.

  10. Miniature near-infrared spectrometer for point-of-use chemical analysis

    Science.gov (United States)

    Friedrich, Donald M.; Hulse, Charles A.; von Gunten, Marc; Williamson, Eric P.; Pederson, Christopher G.; O'Brien, Nada A.

    2014-03-01

    Point-of-use chemical analysis holds tremendous promise for a number of industries, including agriculture, recycling, pharmaceuticals and homeland security. Near infrared (NIR) spectroscopy is an excellent candidate for these applications, with minimal sample preparation for real-time decision-making. We will detail the development of a golf ball-sized NIR spectrometer developed specifically for this purpose. The instrument is based upon a thin-film dispersive element that is very stable over time and temperature, with less than 2 nm change expected over the operating temperature range and lifetime of the instrument. This filter is coupled with an uncooled InGaAs detector array in a small, rugged, environmentally stable optical bench ideally suited to unpredictable environments. The resulting instrument weighs less than 60 grams, includes onboard illumination and collection optics for diffuse reflectance applications in the 900-1700 nm wavelength range, and is USB-powered. It can be driven in the field by a laptop, tablet or even a smartphone. The software design includes the potential for both on-board and cloud-based storage, analysis and decision-making. The key attributes of the instrument and the underlying design tradeoffs will be discussed, focusing on miniaturization, ruggedization, power consumption and cost. The optical performance of the instrument, as well as its fit-for purpose will be detailed. Finally, we will show that our manufacturing process has enabled us to build instruments with excellent unit-to-unit reproducibility. We will show that this is a key enabler for instrumentindependent chemical analysis models, a requirement for mass point-of-use deployment.

  11. Anions Analysis in Ground and Tap Waters by Sequential Chemical and CO2-Suppressed Ion Chromatography

    Directory of Open Access Journals (Sweden)

    Glen Andrew D. De Vera

    2011-06-01

    Full Text Available An ion chromatographic method using conductivity detection with sequential chemical and CO2 suppression was optimized for the simultaneous determination of fluoride, chloride, bromide, nitrate,phosphate and sulfate in ground and tap water. The separation was done using an anion exchange column with an eluent of 3.2 mM Na2CO3 and 3.2 mM NaHCO3 mixture. The method was linear in the concentration range of 5 to 300 μg/L with correlation coefficients greater than 0.99 for the six inorganic anions. The method was also shown to be applicable in trace anions analysis as given by the low method detection limits (MDL. The MDL was 1μg/L for both fluoride and chloride. Bromide, nitrate, phosphate and sulfate had MDLs of 7 μg/L, 10 μg/L, 9 μg/L and 2 μg/L, respectively. Good precision was obtained as shown in the relative standard deviation of 0.1 to 12% for peak area and 0.1 to 0.3% for retention time. The sensitivity of the method improved with the addition of CO2 suppressor to chemical suppression as shown in the lower background conductivity and detection limits. The recoveries of the anions spiked in water at 300 μg/L level ranged from 100 to 104%. The method was demonstrated to be sensitive, accurate and precise for trace analysis of the six anions and was applied in the anions analysis in ground and tap waters in Malolos, Bulacan. The water samples were found to contain high concentrations of chloride of up to 476 mg/L followed by sulfate (38 mg/L, bromide (1 mg/L, phosphate (0.4 mg/L, fluoride (0.2 mg/L and nitrate (0.1 mg/L.

  12. Chemical Analysis of a "Miller-Type" Complex Prebiotic Broth. Part I: Chemical Diversity, Oxygen and Nitrogen Based Polymers

    Science.gov (United States)

    Wollrab, Eva; Scherer, Sabrina; Aubriet, Frédéric; Carré, Vincent; Carlomagno, Teresa; Codutti, Luca; Ott, Albrecht

    2016-06-01

    In a famous experiment Stanley Miller showed that a large number of organic substances can emerge from sparking a mixture of methane, ammonia and hydrogen in the presence of water (Miller, Science 117:528-529, 1953). Among these substances Miller identified different amino acids, and he concluded that prebiotic events may well have produced many of Life's molecular building blocks. There have been many variants of the original experiment since, including different gas mixtures (Miller, J Am Chem Soc 77:2351-2361, 1955; Oró Nature 197:862-867, 1963; Schlesinger and Miller, J Mol Evol 19:376-382, 1983; Miyakawa et al., Proc Natl Acad Sci 99:14,628-14,631, 2002). Recently some of Miller's remaining original samples were analyzed with modern equipment (Johnson et al. Science 322:404-404, 2008; Parker et al. Proc Natl Acad Sci 108:5526-5531, 2011) and a total of 23 racemic amino acids were identified. To give an overview of the chemical variety of a possible prebiotic broth, here we analyze a "Miller type" experiment using state of the art mass spectrometry and NMR spectroscopy. We identify substances of a wide range of saturation, which can be hydrophilic, hydrophobic or amphiphilic in nature. Often the molecules contain heteroatoms, with amines and amides being prominent classes of molecule. In some samples we detect ethylene glycol based polymers. Their formation in water requires the presence of a catalyst. Contrary to expectations, we cannot identify any preferred reaction product. The capacity to spontaneously produce this extremely high degree of molecular variety in a very simple experiment is a remarkable feature of organic chemistry and possibly prerequisite for Life to emerge. It remains a future task to uncover how dedicated, organized chemical reaction pathways may have arisen from this degree of complexity.

  13. Biosensors for the analysis of microbiological and chemical contaminants in food.

    Science.gov (United States)

    McGrath, T F; Elliott, C T; Fodey, T L

    2012-04-01

    Increases in food production and the ever-present threat of food contamination from microbiological and chemical sources have led the food industry and regulators to pursue rapid, inexpensive methods of analysis to safeguard the health and safety of the consumer. Although sophisticated techniques such as chromatography and spectrometry provide more accurate and conclusive results, screening tests allow a much higher throughput of samples at a lower cost and with less operator training, so larger numbers of samples can be analysed. Biosensors combine a biological recognition element (enzyme, antibody, receptor) with a transducer to produce a measurable signal proportional to the extent of interaction between the recognition element and the analyte. The different uses of the biosensing instrumentation available today are extremely varied, with food analysis as an emerging and growing application. The advantages offered by biosensors over other screening methods such as radioimmunoassay, enzyme-linked immunosorbent assay, fluorescence immunoassay and luminescence immunoassay, with respect to food analysis, include automation, improved reproducibility, speed of analysis and real-time analysis. This article will provide a brief footing in history before reviewing the latest developments in biosensor applications for analysis of food contaminants (January 2007 to December 2010), focusing on the detection of pathogens, toxins, pesticides and veterinary drug residues by biosensors, with emphasis on articles showing data in food matrices. The main areas of development common to these groups of contaminants include multiplexing, the ability to simultaneously analyse a sample for more than one contaminant and portability. Biosensors currently have an important role in food safety; further advances in the technology, reagents and sample handling will surely reinforce this position.

  14. Biosensors for the analysis of microbiological and chemical contaminants in food.

    Science.gov (United States)

    McGrath, T F; Elliott, C T; Fodey, T L

    2012-04-01

    Increases in food production and the ever-present threat of food contamination from microbiological and chemical sources have led the food industry and regulators to pursue rapid, inexpensive methods of analysis to safeguard the health and safety of the consumer. Although sophisticated techniques such as chromatography and spectrometry provide more accurate and conclusive results, screening tests allow a much higher throughput of samples at a lower cost and with less operator training, so larger numbers of samples can be analysed. Biosensors combine a biological recognition element (enzyme, antibody, receptor) with a transducer to produce a measurable signal proportional to the extent of interaction between the recognition element and the analyte. The different uses of the biosensing instrumentation available today are extremely varied, with food analysis as an emerging and growing application. The advantages offered by biosensors over other screening methods such as radioimmunoassay, enzyme-linked immunosorbent assay, fluorescence immunoassay and luminescence immunoassay, with respect to food analysis, include automation, improved reproducibility, speed of analysis and real-time analysis. This article will provide a brief footing in history before reviewing the latest developments in biosensor applications for analysis of food contaminants (January 2007 to December 2010), focusing on the detection of pathogens, toxins, pesticides and veterinary drug residues by biosensors, with emphasis on articles showing data in food matrices. The main areas of development common to these groups of contaminants include multiplexing, the ability to simultaneously analyse a sample for more than one contaminant and portability. Biosensors currently have an important role in food safety; further advances in the technology, reagents and sample handling will surely reinforce this position. PMID:22278073

  15. Chemical Derivatization and Ultrahigh Resolution and Accurate Mass Spectrometry Strategies for "Shotgun" Lipidome Analysis.

    Science.gov (United States)

    Ryan, Eileen; Reid, Gavin E

    2016-09-20

    Lipids play critical structural and functional roles in the regulation of cellular homeostasis, and it is increasingly recognized that the disruption of lipid metabolism or signaling or both is associated with the onset and progression of certain metabolically linked diseases. As a result, the field of lipidomics has emerged to comprehensively identify and structurally characterize the diverse range of lipid species within a sample of interest and to quantitatively monitor their abundances under different physiological or pathological conditions. Mass spectrometry (MS) has become a critical enabling platform technology for lipidomic researchers. However, the presence of isobaric (i.e., same nominal mass) and isomeric (i.e., same exact mass) lipids within complex lipid extracts means that MS-based identification and quantification of individual lipid species remains a significant analytical challenge. Ultrahigh resolution and accurate mass spectrometry (UHRAMS) offers a convenient solution to the isobaric mass overlap problem, while a range of chromatographic separation, differential extraction, intrasource separation and selective ionization methods, or tandem mass spectrometry (MS/MS) strategies may be used to address some types of isomeric mass lipid overlaps. Alternatively, chemical derivatization strategies represent a more recent approach for the separation of lipids within complex mixtures, including for isomeric lipids. In this Account, we highlight the key components of a lipidomics workflow developed in our laboratory, whereby certain lipid classes or subclasses, namely, aminophospholipids and O-alk-1'-enyl (i.e., plasmalogen) ether-containing lipids, are shifted in mass following sequential functional group selective chemical derivatization reactions prior to "shotgun" nano-ESI-UHRAMS analysis, "targeted" MS/MS, and automated database searching. This combined derivatization and UHRAMS approach resolves both isobaric mass lipids and certain categories of

  16. Forensic analysis methodology for thermal and chemical characterization of homemade explosives

    International Nuclear Information System (INIS)

    Highlights: • Identification of homemade explosives (HME) is critical for determining the origin of explosive precursor materials. • A novel laser-heating technique was used to obtain the thermal/chemical signatures of HME precursor materials. • Liquid-fuel saturation of the pores of a solid porous oxidizer affected the total specific heat release. • Material thermal signatures were dependent on sample mass and heating rate. • This laser-heating technique can be a useful diagnostic tool for characterizing the thermochemical behavior of HMEs. - Abstract: Forensic identification of homemade explosives is critical for determining the origin of the explosive materials and precursors, and formulation procedures. Normally, the forensic examination of the pre- and post-blast physical evidence lacks specificity for homemade-explosive identification. The focus of this investigation was to use a novel measurement technique, referred to as the laser-driven thermal reactor, to obtain the thermal/chemical signatures of homemade-explosive precursor materials. Specifically, nitromethane and ammonium nitrate were studied under a variety of operating conditions and protocols. Results indicated that liquid-fuel saturation of the internal pores of a solid particle oxidizer appear to be a limiting parameter for the total specific heat release during exothermic processes. Results also indicated that the thermal signatures of these materials are dependent on sample mass and heating rate, for which this dependency may not be detectable by other commercially available thermal analysis techniques. This study has demonstrated that the laser-driven thermal reactor can be a useful diagnostic tool for characterizing the thermal and chemical behavior of trace amounts of homemade-explosive materials

  17. Forensic analysis methodology for thermal and chemical characterization of homemade explosives

    Energy Technology Data Exchange (ETDEWEB)

    Nazarian, Ashot; Presser, Cary, E-mail: cpresser@nist.gov

    2014-01-20

    Highlights: • Identification of homemade explosives (HME) is critical for determining the origin of explosive precursor materials. • A novel laser-heating technique was used to obtain the thermal/chemical signatures of HME precursor materials. • Liquid-fuel saturation of the pores of a solid porous oxidizer affected the total specific heat release. • Material thermal signatures were dependent on sample mass and heating rate. • This laser-heating technique can be a useful diagnostic tool for characterizing the thermochemical behavior of HMEs. - Abstract: Forensic identification of homemade explosives is critical for determining the origin of the explosive materials and precursors, and formulation procedures. Normally, the forensic examination of the pre- and post-blast physical evidence lacks specificity for homemade-explosive identification. The focus of this investigation was to use a novel measurement technique, referred to as the laser-driven thermal reactor, to obtain the thermal/chemical signatures of homemade-explosive precursor materials. Specifically, nitromethane and ammonium nitrate were studied under a variety of operating conditions and protocols. Results indicated that liquid-fuel saturation of the internal pores of a solid particle oxidizer appear to be a limiting parameter for the total specific heat release during exothermic processes. Results also indicated that the thermal signatures of these materials are dependent on sample mass and heating rate, for which this dependency may not be detectable by other commercially available thermal analysis techniques. This study has demonstrated that the laser-driven thermal reactor can be a useful diagnostic tool for characterizing the thermal and chemical behavior of trace amounts of homemade-explosive materials.

  18. CFX-10 Analysis of the High Temperature Thermal- Chemical Experiment (CS28-2)

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Hyoung Tae; Park, Joo Hwan; Rhee, Bo Wook

    2008-02-15

    A Computational Fluid Dynamics (CFD) model of a post-blowdown fuel channel analysis for aged CANDU reactors with crept pressure tube has been developed, and validated against a high temperature thermal-chemical experiment: CS28-2. The CS28-2 experiment is one of three series of experiments to simulate the thermal-chemical behavior of a 28-element fuel channel at a high temperature and a low steam flow rate which may occur in severe accident conditions such as a LBLOCA (Large Break Loss of Coolant Accident) of CANDU reactors. Pursuant to the objective of this study, the current study has focused on understanding the involved phenomena such as the thermal radiation and convection heat transfer, and the high temperature zirconium-steam reaction in a multi-ring geometry. Therefore, a zirconium-steam oxidation model based on a parabolic rate law was implemented into the CFX-10 code, which is a commercial CFD code offered from ANSYS Inc., and other heat transfer mechanisms in the 28-element fuel channel were modeled by the original CFX-10 heat transfer packages. To assess the capability of the CFX-10 code to model the thermal-chemical behavior of the 28-element fuel channel, the measured temperatures of the Fuel Element Simulators (FES) of three fuel rings in the test bundle and the pressure tube, and the hydrogen production in the CS28-2 experiment were compared with the CFX-10 predictions. In spite of some discrepancy between the measurement data and CFX results, it was found that the CFX-10 prediction based on the Urbanic-Heidrick correlation of the zirconium-steam reaction as well as the Discrete Transfer Model for a radiation heat transfer among the FES of three rings and the pressure tube are quite accurate and sound even for the offset a cluster fuel bundle of an aged fuel channel.

  19. Identification of chlorinated solvents degradation zones in clay till by high resolution chemical, microbial and compound specific isotope analysis

    DEFF Research Database (Denmark)

    Damgaard, Ida; Bjerg, Poul Løgstrup; Bælum, Jacob;

    2013-01-01

    subsampling of the clay till cores. The study demonstrates that an integrated approach combining chemical analysis, molecular microbial tools and compound specific isotope analysis (CSIA) was required in order to document biotic and abiotic degradations in the clay till system. © 2013 Elsevier B.V....

  20. How Flow Injection Analysis (FIA) over the past 25 years has changed our way of performing chemical analyses

    DEFF Research Database (Denmark)

    Hansen, Elo Harald; Miró, Manuel

    2007-01-01

    Briefly looking back on the impact of flow injection analysis (FIA), as reflected in the rapid growth of publications in the scientific literature, and touching upon many of the novel and unique analytical chemical possibilities that FIA and its sequels, sequential injection analysis (SIA) and Lab-on-Valve...

  1. Determination of chemical elements in Eucalyptus grandis, manured with Ballad's, by neutrons activation analysis

    International Nuclear Information System (INIS)

    The biosolid is a mud resulting from the biological treatment of wasted liquids. It is considered as a profitable alternative and important to minimize the environmental impact generated by the sewage thrown in to sanitary lands, in forest cultures like the Eucalyptus grandis. The objective of this work was to detect which chemical elements are present in Eucalyptus grandis samples, fertilized with different quantities of biosolid. The eucalyptuses of Estacao Experimental de Ciencias Florestais of Itatinga were planted in March of 1998 and collected with five years old. The used biosolid was produced by Station of Treatment of Sewer of Barueri - SP, classified as kind B. For the determination of the presence and quantity of chemical elements in the eucalyptus samples, an analysis technique by neutronic activation (NAA) was used followed by gamma rays spectroscopy. The samples were irradiated in the Nuclear Reactor IEA-R1 of IPEN-SP, followed by the measure of induced gamma rays activity, using a Detector HPGe. The presence, mainly of Br, Mn, Na and K, was detected in all analyzed samples. (author)

  2. Analysis and modelling of the energy consumption of chemical batch plants

    Energy Technology Data Exchange (ETDEWEB)

    Bieler, P.S.

    2004-07-01

    This report for the Swiss Federal Office of Energy (SFOE) describes two different approaches for the energy analysis and modelling of chemical batch plants. A top-down model consisting of a linear equation based on the specific energy consumption per ton of production output and the base consumption of the plant is postulated. The model is shown to be applicable to single and multi-product batches for batch plants with constant production mix and multi-purpose batch plants in which only similar chemicals are produced. For multipurpose batch plants with highly varying production processes and changing production mix, the top-down model produced inaccurate results. A bottom-up model is postulated for such plants. The results obtained are discussed that show that the electricity consumption for infrastructure equipment was significant and responsible for about 50% of total electricity consumption. The specific energy consumption for the different buildings was related to the degree of automation and the production processes. Analyses of the results of modelling are presented. More detailed analyses of the energy consumption of this apparatus group show that about 30 to 40% of steam energy is lost and thus a large potential for optimisation exists. Various potentials for making savings, ranging from elimination of reflux conditions to the development of a new heating/cooling-system for a generic batch reactor, are identified.

  3. Repeatability, correlation and path analysis of physical and chemical characteristics of peach fruits

    Directory of Open Access Journals (Sweden)

    Rosana Gonçalves Pires Matias

    2014-12-01

    Full Text Available This study aimed to determine the number of measurements necessary to evaluate physical and chemical characteristics of peach fruits, study the relationships between them and their direct and indirect effects on the content of ascorbic acid and total carotenoids. The characteristics skin and pulp color, fruit weight, suture, equatorial and polar diameters, firmness, soluble solids (SS, titratable acidity (TA, SS/TA ratio, ascorbic acid and total carotenoids were evaluated in 39 cultivars of peach and 3 cultivars of nectarine from the orchard of the Universidade Federal de Viçosa. The repeatability coefficient was estimated by ANOVA and CPCOR. Phenotypic correlation coefficients (rf were estimated and, after the multicollinearity diagnostics, they were unfolded to direct and indirect effects of the explanatory variables on the response variable using path analysis. There was agreement on the magnitude of repeatability coefficients obtained by the two methods; however, they varied among the 14 characteristics. The highest correlations were found between FW, SD, ED and PD. Seven fruits are sufficient to evaluate the physical and chemical characteristics of peach with a correlation coefficient of 90%. The characteristics considered in the path diagrams (b* skin, hº skin, b* pulp, hº pulp, ED, PD, FIR, SS, SS/AT and TC are not the main determinants of the ascorbic acid. The yellow hue of the pulp (hº pulp has the potential to be used in indirect selection for total carotenoids.

  4. Kinetics analysis of chemiluminescence in discharge-driven HF chemical lasers

    Institute of Scientific and Technical Information of China (English)

    Wei Luo; Shengfu Yuan; Baozhu Yan; Qisheng Lu; Qianjin Zou

    2011-01-01

    The chcinilummescence spectrum in the optical cavity of discharge-driven hydrogen fluoride (HF) chemical laser is measured. The result reveals that the spectra of the helium and fluorine (F) atoms are the major components. Moreover, the green chemiluminescence in the downstream of the optical axis is mostly composed of the 60P20 spectral line of the HF molecule. The analysis shows that, except for the cold pumping reaction, the recombination of the F atoms and the hot pumping reaction also occur in the optical cavity. Due to the hot. Pumping reaction and the optical cavity temperature in a specific range, the 60P20 line becomes the strongest HF molecule in the downstream region of the optical axis. After the hot pumping reaction, the green chcmilum inference always appears in the downstream region of the optical axis when the optical cavity temperature varies in a greater range.%@@ The chemiluminescence spectrum in the optical cavity of discharge-driven hydrogen fluoride(HF) chemical laser is measured.The result reveals that the spectra of the helium and fluorine(F) atoms are the major components.Moreover,the green chemiluminescence in the downstream of the optical axis is mostly composed of the 60P20 spectral line of the HF molecule.

  5. Chemical analysis and antihyperglycemic activity of an original extract from burdock root (Arctium lappa).

    Science.gov (United States)

    Tousch, Didier; Bidel, Luc P R; Cazals, Guillaume; Ferrare, Karine; Leroy, Jeremy; Faucanié, Marie; Chevassus, Hugues; Tournier, Michel; Lajoix, Anne-Dominique; Azay-Milhau, Jacqueline

    2014-08-01

    In the present study, we obtained a dried burdock root extract (DBRE) rich in caffeoylquinic acids derivatives. We performed the chemical characterization of DBRE and explored its antihyperglycemic potential in both in vitro and in vivo experiments. Chemical analysis of DBRE using LC-MS and GC-MS revealed the presence of a great majority of dicaffeoylquinic acid derivatives (75.4%) of which 1,5-di-O-caffeoyl-4-O-maloylquinic acid represents 44% of the extract. In the in vitro experiments, DBRE is able to increase glucose uptake in cultured L6 myocytes and to decrease glucagon-induced glucose output from rat isolated hepatocytes together with a reduction of hepatic glucose 6-phosphatase activity. DBRE did not increase insulin secretion in the INS-1 pancreatic β-cell line. In vivo, DBRE improves glucose tolerance both after intraperitoneal and oral subchronic administration. In conclusion, our data demonstrate that DBRE constitutes an original set of caffeoylquinic acid derivatives displaying antihyperglycemic properties.

  6. Chemical analysis and antihyperglycemic activity of an original extract from burdock root (Arctium lappa).

    Science.gov (United States)

    Tousch, Didier; Bidel, Luc P R; Cazals, Guillaume; Ferrare, Karine; Leroy, Jeremy; Faucanié, Marie; Chevassus, Hugues; Tournier, Michel; Lajoix, Anne-Dominique; Azay-Milhau, Jacqueline

    2014-08-01

    In the present study, we obtained a dried burdock root extract (DBRE) rich in caffeoylquinic acids derivatives. We performed the chemical characterization of DBRE and explored its antihyperglycemic potential in both in vitro and in vivo experiments. Chemical analysis of DBRE using LC-MS and GC-MS revealed the presence of a great majority of dicaffeoylquinic acid derivatives (75.4%) of which 1,5-di-O-caffeoyl-4-O-maloylquinic acid represents 44% of the extract. In the in vitro experiments, DBRE is able to increase glucose uptake in cultured L6 myocytes and to decrease glucagon-induced glucose output from rat isolated hepatocytes together with a reduction of hepatic glucose 6-phosphatase activity. DBRE did not increase insulin secretion in the INS-1 pancreatic β-cell line. In vivo, DBRE improves glucose tolerance both after intraperitoneal and oral subchronic administration. In conclusion, our data demonstrate that DBRE constitutes an original set of caffeoylquinic acid derivatives displaying antihyperglycemic properties. PMID:24933284

  7. Characterization of plutonium-bearing wastes by chemical analysis and analytical electron microscopy

    Energy Technology Data Exchange (ETDEWEB)

    Behrens, R.G. [Los Alamos National Lab., NM (United States); Buck, E.C.; Dietz, N.L.; Bates, J.K.; Van Deventer, E.; Chaiko, D.J. [Argonne National Lab., IL (United States)

    1995-09-01

    This report summarizes the results of characterization studies of plutonium-bearing wastes produced at the US Department of Energy weapons production facilities. Several different solid wastes were characterized, including incinerator ash and ash heels from Rocky Flats Plant and Los Alamos National Laboratory; sand, stag, and crucible waste from Hanford; and LECO crucibles from the Savannah River Site. These materials were characterized by chemical analysis and analytical electron microscopy. The results showed the presence of discrete PuO{sub 2}PuO{sub 2{minus}x}, and Pu{sub 4}O{sub 7} phases, of about 1{mu}m or less in size, in all of the samples examined. In addition, a number of amorphous phases were present that contained plutonium. In all the ash and ash heel samples examined, plutonium phases were found that were completely surrounded by silicate matrices. Consequently, to achieve optimum plutonium recovery in any chemical extraction process, extraction would have to be coupled with ultrafine grinding to average particle sizes of less than 1 {mu}m to liberate the plutonium from the surrounding inert matrix.

  8. The measurement of the chemically mobile fraction of lead in soil using isotopic dilution analysis

    International Nuclear Information System (INIS)

    The chemically available fraction of lead in eight soils measured by isotopic dilution analysis using 212Pb ranged from 7 to 16% of the total content of lead in soil. The soluble fractions achieved values up to 63% of the total content in 1 M NH4NO3, 1 M MgCl2 and 0.05 M DTPA solutions. Increasing the contact time between water and soil, the water-soil ratio from 1:1 to 5:1 and increasing the temperature of the soil-water suspension raised the chemically available fraction in soil. Comparing various soil parameters and the mobile fraction of lead, only pH shows a significant correlation. The amphoteric character of lead causes a minimum of mobility about pH 6; pH-values below are responsible for the higher mobility of lead as Pb2+, at pH-values above 6 soluble hydroxy and humic acid complexes are formed. (orig.)

  9. Elemental composition method for computation and analysis of simultaneous chemical and phase equilibrium

    Institute of Scientific and Technical Information of China (English)

    2000-01-01

    An elemental composition method for computation and analysis of simultaneous chemical and phase equilibrium (CPE) of non-ideal mixtures is proposed. The concept of element is defined, the relationship between component composition and elemental composition is derived, and the concept of elemental potential and its physical meaning are further cleared from the view point of thermodynamics. The relationship between chemical potential and elemental potential is derived in the thermodynamic principles, and the computation equations for CPE problem are obtained based on elemental potential. A simple form of necessary and sufficient condition in terms of elemental composition for reactive azeotropes is derived, which takes the same functional form as the condition for azeotropes in non-reactive systems. The element in this note may be atoms, molecules or group radicals. The presented method is applicable to CPE problem of non-ideal mixtures, and the computation can be simplified by the dimension reducing method. The presented method was supplied to compute and analyze CPE problem of several examples and it is found that it is a robust and efficient method.

  10. The radiometric analysis of non-radioactive materials by chemical exchange

    International Nuclear Information System (INIS)

    The use of radioisotopes to measure the composition of different materials via chemical exchange within an instrument is described. The product of the reaction is a radioactive gas which is counted and serves as the indicator of measurement. This method has been applied to a number of different liquids and gases for their specific and sensitive determination. The chief limiting condition on sensitivity is imposed by the specific activity of the radiochemical component. Where high specific activities are available, sensitivity in terms of chemical quantity will be very great. The recent development of quinol- Kr85 clathrate compounds has provided a basic radiochemical source which not only provides high specific activities at low cost but also excellent half-life and energy characteristics. These clathrate compounds can be oxidized only by very strong oxidizing agents, such as ozone to release Kr85. When coupled with a salt, such as sodium chlorite, the sensing of reducing materials such as SO2 may be accomplished. Two applications of the radiometric technique employing clathrates are described. The first is the development of a balloon-borne sonde for the meteorological analysis of ozone in the upper atmosphere. The other is its use in air pollution and process control work in the form of a portable analyser. Different gases may be analysed by this device by merely changing the radiochemical reaction cell. (author)

  11. Substance Flow Analysis and Source Mapping of Chemical UV-filters

    Energy Technology Data Exchange (ETDEWEB)

    Eriksson, E., E-mail: eve@env.dtu.dk; Andersen, H. R.; Ledin, A. [Technical University of Denmark, Department of Environmental Engineering (Denmark)

    2008-12-15

    Chemical ultraviolet (UV)-filters are used in sunscreens to protect the skin from harmful UV radiation which may otherwise cause sunburns and skin cancer. Commonly used chemical UV-filters are known to cause endocrine disrupting effects in both aquatic and terrestrial animals as well as in human skin cells. Here, source mapping and substance flow analysis were applied to find the sources of six UV-filters (oxybenzone, avobenzone, 4-methylbenzylidene camphor, octyl methoxycinnamate, octyl dimethyl PABA and homosalate) and to identify the most dominant flows of these substances in Denmark. Urban water, composed of wastewater and surface waters, was found to be the primary recipient of UV-filters, whereby wastewater received an estimated 8.5-65 tonnes and surface waters received 7.1-51 tonnes in 2005. In wastewater treatment plants, their sorption onto sludge is perceived to be an important process and presence in effluents can be expected due to a lack of biodegradability. In addition, the use of UV-filters is expected to continue to increase significantly. Not all filters (e.g., octyl dimethyl PABA and homosalate) are used in Denmark. For example, 4-MBC is mainly associated with self-tanning liquids and private import of sunscreens.

  12. Thermogravimetric analysis of cobalt-filled carbon nanotubes deposited by chemical vapour deposition

    Energy Technology Data Exchange (ETDEWEB)

    Ramesh, Babu P. [Materials Ireland Polymer Research Centre, Trinity College, Dublin-1 (Ireland); Blau, W.J. [Materials Ireland Polymer Research Centre, Trinity College, Dublin-1 (Ireland); Tyagi, P.K. [Department of Physics, Indian Institute of Technology, Bombay (India); Misra, D.S. [Department of Physics, Indian Institute of Technology, Bombay (India); Ali, N. [Department of Mechanical Engineering, University of Aveiro, 3810-193 Aveiro (Portugal); Gracio, J. [Department of Mechanical Engineering, University of Aveiro, 3810-193 Aveiro (Portugal); Cabral, G. [Department of Mechanical Engineering, University of Aveiro, 3810-193 Aveiro (Portugal); Titus, E. [Department of Mechanical Engineering, University of Aveiro, 3810-193 Aveiro (Portugal)]. E-mail: elby@mec.ua.pt

    2006-01-03

    In this paper, we report results from an investigation studying the purification of Co-filled carbon nanotubes (CNTs) using Thermogravimetric analysis (TGA). The as-grown CNTs were prepared using Microwave Plasma Chemical Vapour Deposition (MPCVD). Transmission electron microscopy (TEM), Fourier Transform Infrared (FTIR) and Raman spectroscopy were used to characterise the CNT samples. The CNTs produced by MPCVD were filled with cobalt and consisted of thick multi-walls. After TGA purification at 900 deg. C, 30 wt.% Co-filled CNTs remained in the TGA pan. However, while investigating the un-filled commercial CNTs (thin multiwalled), the sample completely burnt out at around 650 deg. C in the TGA furnace. The high thermal stability and the ability of thick-walled CNTs to act as an effective protective shield which prevents the oxidation of encapsulated cobalt have been demonstrated.

  13. Biological uptake analysis of organisms exposed to oil and chemically dispersed oil

    Energy Technology Data Exchange (ETDEWEB)

    Coelho, G. M.; Aurand, D. V. [Ecosystem Management and Associates Inc., Purcellville, VA (United States); Wright, D. A. [Maryland Univ., Chesapeake Biological Laboratory, Solomons, MD (United States)

    1999-07-01

    This paper presents the results of a preliminary evaluation of tissue samples that were archived from a full-scale biological study of water column, inter-tidal and benthic organisms exposed to weathered Arabian crude oil or to the same oil that was chemically dispersed with Corexit 9500. At various intervals during the experiment, fish, oysters and polychaetes were removed from the mesocosm tanks, and the tissue was analyzed for 40 individual PAHs using gas chromatography/mass spectrometry. It was found that it is possible to track PAH body burden in test animal tissues, even if the water column exposure period is very short, therefore inclusion of this type of analysis in future studies would be useful in evaluating effects of thresholds for various profiles, in both mesocosm and laboratory studies. 16 refs., 1 tab., 2 figs.

  14. Biological uptake analysis of organisms exposed to oil and chemically dispersed oil

    Energy Technology Data Exchange (ETDEWEB)

    Coelho, G. M.; Aurand, D. V. [Ecosystem Management and Associates Inc., Purcellville, VA (United States); Wright, D. A. [Maryland Univ., Chesapeake Biological Laboratory, Solomons, MD (United States)

    1999-08-01

    This paper presents the results of a preliminary evaluation of tissue samples that were archived from a full-scale biological study of water column, inter-tidal and benthic organisms exposed to weathered Arabian crude oil or to the same oil that was chemically dispersed with Corexit 9500. At various intervals during the experiment, fish, oysters and polychaetes were removed from the mesocosm tanks, and the tissue was analyzed for 40 individual PAHs using gas chromatography/mass spectrometry. It was found that it is possible to track PAH body burden in test animal tissues, even if the water column exposure period is very short, therefore inclusion of this type of analysis in future studies would be useful in evaluating effects of thresholds for various profiles, in both mesocosm and laboratory studies. 16 refs., 1 tab., 2 figs.

  15. Spectral Analysis by XANES Reveals that GPNMB Influences the Chemical Composition of Intact Melanosomes

    Energy Technology Data Exchange (ETDEWEB)

    T Haraszti; C Trantow; A Hedberg-Buenz; M Grunze; M Anderson

    2011-12-31

    GPNMB is a unique melanosomal protein. Unlike many melanosomal proteins, GPNMB has not been associated with any forms of albinism, and it is unclear whether GPNMB has any direct influence on melanosomes. Here, melanosomes from congenic strains of C57BL/6J mice mutant for Gpnmb are compared to strain-matched controls using standard transmission electron microscopy and synchrotron-based X-ray absorption near-edge structure analysis (XANES). Whereas electron microscopy did not detect any ultrastructural changes in melanosomes lacking functional GPNMB, XANES uncovered multiple spectral phenotypes. These results directly demonstrate that GPNMB influences the chemical composition of melanosomes and more broadly illustrate the potential for using genetic approaches in combination with nano-imaging technologies to study organelle biology.

  16. Use of thermal neutron reflection method for chemical analysis of bulk samples

    Energy Technology Data Exchange (ETDEWEB)

    Papp, A., E-mail: papppa@atomki.hu [Institute of Nuclear Research of the Hungarian Academy of Sciences, (ATOMKI), 4001 Debrecen, Pf. 51 (Hungary); Csikai, J. [Institute of Nuclear Research of the Hungarian Academy of Sciences, (ATOMKI), 4001 Debrecen, Pf. 51 (Hungary); Institute of Experimental Physics, University Debrecen (IEP), 4010 Debrecen-10, Pf. 105 (Hungary)

    2014-09-11

    Microscopic, σ{sub β}, and macroscopic, Σ{sub β}, reflection cross-sections of thermal neutrons averaged over bulk samples as a function of thickness (z) are given. The σ{sub β} values are additive even for bulk samples in the z=0.5–8 cm interval and so the σ{sub βmol}(z) function could be given for hydrogenous substances, including some illicit drugs, explosives and hiding materials of ∼1000 cm{sup 3} dimensions. The calculated excess counts agree with the measured R(z) values. For the identification of concealed objects and chemical analysis of bulky samples, different neutron methods need to be used simultaneously. - Highlights: • Check the proposed analytical expression for the description of the flux. • Determination of the reflection cross-sections averaged over bulk samples. • Data rendered to estimate the excess counts for various materials.

  17. Microstructure analysis of chemically synthesized wurtzite-type CdS nanocrystals

    Indian Academy of Sciences (India)

    DEKA KULDEEP; KALITA M P C

    2016-05-01

    Microstructure of chemically synthesized wurtzite-type CdS nanocrystals have been investigated by X-ray diffraction (XRD) peak profile analysis by applying different forms of Williamson–Hall (WH) method viz., uniform deformation model (UDM), uniform stress deformation model (USDM) and uniform deformation energy density model (UDEDM), and transmission electron microscope (TEM) observations. The WH methods show the average crystallite size to beabout 10 nm. Strain, stress and energy density of the nanocrystals are found to be $1.18 \\times 10^{−2}, 0.43$ GPa and $2.27$ kJ m$^{−3}$, respectively. High-resolution TEM (HRTEM) results show the nanocrystals to be in spherical shape with an average crystallite size of 10 nm, thereby complementing the size estimation by WH methods. Further, HRTEM observations reveal the presence of edge dislocations and twin boundaries within the nanocrystals.

  18. Determination of chemical pollutants in the atmosphere of the Valley of Toluca by neutron activation analysis

    International Nuclear Information System (INIS)

    The studies about the presence of contaminants in the atmosphere of diverse cities have been increased widely because to the problems that those cause to public health. Because of this in 1986 was made an Atmospheric Monitoring Program in the Valley of Toluca including the city of Toluca and Toluca- Lerma industrial corridor. That program consist of a preliminary net of sampling for the recollection of total suspended particles on glass-fiber filters, the sampling was performed two times a week in five different zones. To date have been analyzed some of these filters by atomic absorption in the Chemistry School of the Mexico's State University. In this work, is showed the establishment of chemical treatment technique and the results of quantitative analysis through neutron activation in filters of recent monitoring. (Author)

  19. An Intelligent System for Modelling, Design and Analysis of Chemical Processes

    DEFF Research Database (Denmark)

    Gani, Rafiqul

    ICAS, Integrated Computer Aided System, is a software that consists of a number of intelligent tools, which are very suitable, among others, for computer aided modelling, sustainable design of chemical and biochemical processes, and design-analysis of product-process monitoring systems. Each...... the computer aided modelling tool will illustrate how to generate a desired process model, how to analyze the model equations, how to extract data and identify the model and make it ready for various types of application. In sustainable process design, the example will highlight the issue of integration...... results so that the user can make intelligent decisions to proceed to the next step. The tools contain in-house databases, especially designed to work in an integrated manner with tool specific ontology for efficient knowledge management. Examples highlighting the use of the tools willl be given, where...

  20. Design of sustainable chemical processes: Systematic retrofit analysis, generation and evaluation alternatives

    DEFF Research Database (Denmark)

    Carvalho, Ana; Gani, Rafiqul; Matos, Henrique

    2008-01-01

    -aided tool has been developed to facilitate the calculations needed for the application of the methodology. The application of the indicator-based methodology and the developed software are highlighted through a process flowsheet for the production of vinyl chlorine monomer (VCM).......The objective of this paper is to present a generic and systematic methodology for identifying the feasible retrofit design alternatives of any chemical process. The methodology determines a set of mass and energy indicators from steady-state process data, establishes the operational and design...... targets, and through a sensitivity-based analysis, identifies the design alternatives that can match a set of design targets. The significance of this indicator-based method is that it is able to identify alternatives, where one or more performance criteria (factors) move in the same direction thereby...

  1. Assessment of some chemical element contents in Traganum nudatum Del shrub using instrumental neutron activation analysis

    Institute of Scientific and Technical Information of China (English)

    Bouzid Nedjimi; Brahim Beladel

    2015-01-01

    Instrumental neutron activation analysis (INAA) has been used to determine some chemical element contents (K, Ca, Na, Fe, Zn, Co, Eu, Sb, and Sc) in Traganum nudatum Del (Chenopodiaceae family) consumed in North African rangelands by sheep livestock. Samples were collected from the area of Djelfa in an arid steppe of Algeria. Results show that pasture halophyte had sufficient levels of K, Ca, Zn, and Co to meet the requirements of ruminants. However, it seems that this halophyte shrub had substantial amounts of Na, higher than the critical level established by the National Research Council (NRC). Eu, Sb, and Sc were within the safety baseline of all the assayed elements recommended by the NRC. The high Na content (∼10 g/kg) in this halophytic species requires elevated intake of water by livestock.

  2. Chemical Species, Micromorphology, and XRD Fingerprint Analysis of Tibetan Medicine Zuotai Containing Mercury

    Science.gov (United States)

    Li, Cen; Yang, Hongxia; Xiao, Yuancan; Zhandui; Sanglao; Wang, Zhang; Ladan, Duojie; Bi, Hongtao

    2016-01-01

    Zuotai (gTso thal) is one of the famous drugs containing mercury in Tibetan medicine. However, little is known about the chemical substance basis of its pharmacodynamics and the intrinsic link of different samples sources so far. Given this, energy dispersive spectrometry of X-ray (EDX), scanning electron microscopy (SEM), atomic force microscopy (AFM), and powder X-ray diffraction (XRD) were used to assay the elements, micromorphology, and phase composition of nine Zuotai samples from different regions, respectively; the XRD fingerprint features of Zuotai were analyzed by multivariate statistical analysis. EDX result shows that Zuotai contains Hg, S, O, Fe, Al, Cu, and other elements. SEM and AFM observations suggest that Zuotai is a kind of ancient nanodrug. Its particles are mainly in the range of 100–800 nm, which commonly further aggregate into 1–30 μm loosely amorphous particles. XRD test shows that β-HgS, S8, and α-HgS are its main phase compositions. XRD fingerprint analysis indicates that the similarity degrees of nine samples are very high, and the results of multivariate statistical analysis are broadly consistent with sample sources. The present research has revealed the physicochemical characteristics of Zuotai, and it would play a positive role in interpreting this mysterious Tibetan drug. PMID:27738409

  3. CHEMICAL ANALYSIS AND ANTIOXIDANT ACTIVITY OF “NERIUM OLEANDER” LEAVES

    Directory of Open Access Journals (Sweden)

    Lakhmili Siham

    2014-01-01

    Full Text Available The phenolic products of medicinal plants have a great pharmacological interest. This product gives the powers of medicinal plants. They are the source of several active principles widely used in modern medicine. The use of Nerium oleander in Moroccan traditional medicine is very common. Few studies have focused on the chemical analysis and phenolic compounds of this plant. For this, we investigated the mineral composition and phenolic combination of the leaves oleander and the study of the antioxidant activity. The mineral analysis shows a very high level of potassium and protein. The biochemical studies revealed a very high quantity of polyphenols in the leaves. Thus, the HPLC analysis of the phenolic fraction shows great variability of substances. The cinnamic acid is the majors compounds identified in the phenolic fraction. The other compounds identified are catechin, epicatechine, chlorogenic acid. This present study which is made for the first time showed a very important antioxidant effect, the value of IC50 (The half maximal inhibitory concentration of DPPH is 0,43 mg mL-1 for the phenolic fraction. On the other hand, the antioxydant activity of the organic extract, the methanolique fraction, n-butanolique fraction and the decoction, has a percentage of inhibition of DPPH over than 90% at a concentration of µg/mL. IC50% values are respectively 0,005 mg mL-1; 0,018 mg mL-1 and 0,005 mg mL-1.

  4. Chemical analysis of interstitial water in rivers of Centro Experimental Aramar area

    Energy Technology Data Exchange (ETDEWEB)

    Matoso, Erika; Goncalves, Julia Rosa, E-mail: ematoso@hotmail.com [Centro Tecnologico da Marinha (CE/CTM-SP), Ipero, SP (Brazil). Centro Experimental Aramar; Cadore, Solange [Universidade Estadual de Campinas (UNICAMP), Campinas, SP (Brazil). Instituto de Quimica. Departamento de Quimica Analitica

    2013-07-01

    This work presents the results from analysis of samples of interstitial waters for the following chemical parameters: F{sup -}, Cl{sup -}, NO{sub 2}{sup -}, Br{sup -}, NO{sub 3}{sup -}, PO{sub 4}{sup 3-}, SO{sub 4}{sup 2-} by Ionic Chromatography, Na, K by Flame Photometry, Al, Cd, Pb, Cu, Cr, Fe, Mn, Ni, Zn by ICP OES, pH and the biological parameter: toxicity by natural bioluminescent bacterium (Vibrio fischeri) bioassay. The samples were obtained from sediments collected in 6 different sampling locations, in a ratio of 10-km-long from Centro Experimental Aramar (CEA). The rivers were the samples came from were: Ipanema River, Sorocaba River and Ribeirao do Ferro River. The interstitial water was extracted by centrifugation (3000 rpm, 20 min, 4 deg C). Analysis for metal concentrations were carried out after acid digestion and others tests proceeded in the sample after filtration without further treatment. These data will contribute to evaluate the distribution of contaminants and nutrients in these collecting points and this toxicity status. The release of soluble substances from sediments to interstitial water provides one way for bioaccumulation of these compounds and may affect the survival or development of aquatic organisms. The analysis in interstitial water has never been evaluated at this sampling points and the importance of this study is collecting data providing a better knowledge of the hydrological conditions in which Centro Experimental Aramar is located. (author)

  5. Chemical Species, Micromorphology, and XRD Fingerprint Analysis of Tibetan Medicine Zuotai Containing Mercury

    Directory of Open Access Journals (Sweden)

    Cen Li

    2016-01-01

    Full Text Available Zuotai (gTso thal is one of the famous drugs containing mercury in Tibetan medicine. However, little is known about the chemical substance basis of its pharmacodynamics and the intrinsic link of different samples sources so far. Given this, energy dispersive spectrometry of X-ray (EDX, scanning electron microscopy (SEM, atomic force microscopy (AFM, and powder X-ray diffraction (XRD were used to assay the elements, micromorphology, and phase composition of nine Zuotai samples from different regions, respectively; the XRD fingerprint features of Zuotai were analyzed by multivariate statistical analysis. EDX result shows that Zuotai contains Hg, S, O, Fe, Al, Cu, and other elements. SEM and AFM observations suggest that Zuotai is a kind of ancient nanodrug. Its particles are mainly in the range of 100–800 nm, which commonly further aggregate into 1–30 μm loosely amorphous particles. XRD test shows that β-HgS, S8, and α-HgS are its main phase compositions. XRD fingerprint analysis indicates that the similarity degrees of nine samples are very high, and the results of multivariate statistical analysis are broadly consistent with sample sources. The present research has revealed the physicochemical characteristics of Zuotai, and it would play a positive role in interpreting this mysterious Tibetan drug.

  6. Atmospheric pressure chemical ionization Fourier transform ion cyclotron resonance mass spectrometry for complex thiophenic mixture analysis

    KAUST Repository

    Hourani, Nadim

    2013-10-01

    Rationale Polycyclic aromatic sulfur heterocycles (PASHs) are detrimental species for refining processes in petroleum industry. Current mass spectrometric Methods that determine their composition are often preceded by derivatization and dopant addition approaches. Different ionization Methods have different impact on the molecular assignment of complex PASHs. The analysis of such species under atmospheric pressure chemical ionization (APCI) is still considered limited due to uncontrolled ion generation with low- and high-mass PASHs. Methods The ionization behavior of a model mixture of five selected PASH standards was investigated using an APCI source with nitrogen as the reagent gas. A complex thiophenic fraction was separated from a vacuum gas oil (VGO) and injected using the same method. The samples were analyzed using Fourier transform ion cyclotron resonance mass spectrometry (FTICR MS). RESULTS PASH model analytes were successfully ionized and mainly [M + H]+ ions were produced. The same ionization pattern was observed for the real thiophenic sample. It was found that S1 class species were the major sulfur-containing species found in the VGO sample. These species indicated the presence of alkylated benzothiophenic (BT), dibenzothiophenic (DBT) and benzonaphthothiophenic (BNT) series that were detected by APCI-FTICR MS. CONCLUSIONS This study provides an established APCI-FTICR MS method for the analysis of complex PASHs. PASHs were detected without using any derivatization and without fragmentation. The method can be used for the analysis of S-containing crude oil samples. © 2013 John Wiley & Sons, Ltd.

  7. Final Safety Analysis Document for Building 693 Chemical Waste Storage Building at Lawrence Livermore National Laboratory

    International Nuclear Information System (INIS)

    This Safety Analysis Document (SAD) for the Lawrence Livermore National Laboratory (LLNL) Building 693, Chemical Waste Storage Building (desipated as Building 693 Container Storage Unit in the Laboratory's RCRA Part B permit application), provides the necessary information and analyses to conclude that Building 693 can be operated at low risk without unduly endangering the safety of the building operating personnel or adversely affecting the public or the environment. This Building 693 SAD consists of eight sections and supporting appendices. Section 1 presents a summary of the facility designs and operations and Section 2 summarizes the safety analysis method and results. Section 3 describes the site, the facility desip, operations and management structure. Sections 4 and 5 present the safety analysis and operational safety requirements (OSRs). Section 6 reviews Hazardous Waste Management's (HWM) Quality Assurance (QA) program. Section 7 lists the references and background material used in the preparation of this report Section 8 lists acronyms, abbreviations and symbols. Appendices contain supporting analyses, definitions, and descriptions that are referenced in the body of this report

  8. A rapid chemical method for lysing Arabidopsis cells for protein analysis

    Directory of Open Access Journals (Sweden)

    Takano Tetsuo

    2011-07-01

    Full Text Available Abstract Background Protein extraction is a frequent procedure in biological research. For preparation of plant cell extracts, plant materials usually have to be ground and homogenized to physically break the robust cell wall, but this step is laborious and time-consuming when a large number of samples are handled at once. Results We developed a chemical method for lysing Arabidopsis cells without grinding. In this method, plants are boiled for just 10 minutes in a solution containing a Ca2+ chelator and detergent. Cell extracts prepared by this method were suitable for SDS-PAGE and immunoblot analysis. This method was also applicable to genomic DNA extraction for PCR analysis. Our method was applied to many other plant species, and worked well for some of them. Conclusions Our method is rapid and economical, and allows many samples to be prepared simultaneously for protein analysis. Our method is useful not only for Arabidopsis research but also research on certain other species.

  9. A model for reliability analysis and calculation applied in an example from chemical industry

    Directory of Open Access Journals (Sweden)

    Pejović Branko B.

    2010-01-01

    Full Text Available The subject of the paper is reliability design in polymerization processes that occur in reactors of a chemical industry. The designed model is used to determine the characteristics and indicators of reliability, which enabled the determination of basic factors that result in a poor development of a process. This would reduce the anticipated losses through the ability to control them, as well as enabling the improvement of the quality of production, which is the major goal of the paper. The reliability analysis and calculation uses the deductive method based on designing of a scheme for fault tree analysis of a system based on inductive conclusions. It involves the use standard logical symbols and rules of Boolean algebra and mathematical logic. The paper eventually gives the results of the work in the form of quantitative and qualitative reliability analysis of the observed process, which served to obtain complete information on the probability of top event in the process, as well as objective decision making and alternative solutions.

  10. Hazard screening of chemical releases and environmental equity analysis of populations proximate to toxic release inventory facilities in Oregon.

    Science.gov (United States)

    Neumann, C M; Forman, D L; Rothlein, J E

    1998-04-01

    A comprehensive approach using hazard screening, demographic analysis, and a geographic information system (GIS) for mapping is employed to address environmental equity issues in Oregon. A media-specific chronic toxicity index [or chronic index (CI)] was used to compare environmental chemical releases reported in the EPA's Toxic Chemical Release Inventory (TRI) database. In 1992, 254 facilities reportedly released more than 40 million pounds of toxic chemicals directly into the environment on-site or transferred them to sewage treatment plants or other off-site facilities for disposal and recycling. For each reported on-site TRI chemical release, a CI based on oral toxicity factors and total mass was calculated. CIs were aggregated on a media-, facility-, and chemical-specific basis. Glycol ethers, nickel, trichloroethylene, chloroform, and manganese were ranked as the top five chemicals released statewide based on total CI. In contrast, based on total mass, methanol, nickel, ammonia, acetone, and toluene were identified as the top five TRI chemicals released in Oregon. TRI facility rankings were related to the demographics and household income of surrounding neighborhoods using bivariate GIS mapping and statistical analysis. TRI facilities were disproportionately located in racial and ethnic minority neighborhoods. They were also located in areas with lower incomes compared to those in the surrounding county. No relationship was observed between the hazard ranking of the TRI facilities overall and socioeconomic characteristics of the community in which they were located.

  11. Vacuum Enhanced X-Ray Florescent Scanner Allows On-The-Spot Chemical Analysis

    Science.gov (United States)

    2004-01-01

    Teamed with KeyMaster Technologies, Kennewick, Washington, the Marshall Space Flight Center engineers have developed a portable vacuum analyzer that performs on-the-spot chemical analyses under field conditions- a task previously only possible in a chemical laboratory. The new capability is important not only to the aerospace industry, but holds potential for broad applications in any industry that depends on materials analysis, such as the automotive and pharmaceutical industries. Weighing in at a mere 4 pounds, the newly developed handheld vacuum X-ray fluorescent analyzer can identify and characterize a wide range of elements, and is capable of detecting chemical elements with low atomic numbers, such as sodium, aluminum and silicon. It is the only handheld product on the market with that capability. Aluminum alloy verification is of particular interest to NASA because vast amounts of high-strength aluminum alloys are used in the Space Shuttle propulsion system such as the External Tank, Main Engine, and Solid Rocket Boosters. This capability promises to be a boom to the aerospace community because of unique requirements, for instance, the need to analyze Space Shuttle propulsion systems on the launch pad. Those systems provide the awe-inspiring rocket power that propels the Space Shuttle from Earth into orbit in mere minutes. The scanner development also marks a major improvement in the quality assurance field, because screws, nuts, bolts, fasteners, and other items can now be evaluated upon receipt and rejected if found to be substandard. The same holds true for aluminum weld rods. The ability to validate the integrity of raw materials and partially finished products before adding value to them in the manufacturing process will be of benefit not only to businesses, but also to the consumer, who will have access to a higher value product at a cheaper price. Three vacuum X-ray scanners are already being used in the Space Shuttle Program. The External Tank

  12. An analysis of strategies used by chemistry instructors to address student alternate conceptions in chemical equilibrium

    Science.gov (United States)

    Piquette, Jeff Stephen

    This study explored general-chemistry instructors' awareness of and ability to identify common student alternate conceptions in chemical equilibrium. Instructor strategies directed at remediation of student alternate conceptions were also investigated and compared to successful, literature-based conceptual change methods. Fifty-two general chemistry instructor volunteers from 50 U.S. colleges and universities completed an interactive web-based survey that gathered their responses to open-ended questions, a rating scale, classroom scenarios, and a demographic form. The three scenarios asked respondents to evaluate hypothetical student exam answers, justify their evaluations, and report how they would assist students to better understand ideas about which they held alternate conceptions. Survey respondents who provided responses or remediation strategies that needed further clarification were sampled (n = 6); each amplified their views in an individual, researcher-led semi-structured phone interview. All survey responses and interview transcriptions were independently analyzed by three raters who followed Patton's (1990) guidelines for qualitative data analysis. Data analysis established that all 52 instructors of chemistry were able to report and identify common student alternate conceptions in chemical equilibrium. Those instructor-reported alternate conceptions were congruent with previously identified alternate conceptions (misconceptions) found in published literature, thus providing validation support for the earlier compilations. This study revealed that chemistry instructors employ a variety of strategies in efforts to address and remediate alternate conceptions. However, those strategies rarely include all four conditions outlined by Posner, Strike, Hewson, and Gertzog (1982) needed to stimulate conceptual change in students. Instructors are thus encouraged to become familiar with successful conceptual change strategies, using such methods as appropriate in

  13. Chemical analysis and quality control of Ginkgo biloba leaves, extracts, and phytopharmaceuticals.

    Science.gov (United States)

    van Beek, Teris A; Montoro, Paola

    2009-03-13

    The chemical analysis and quality control of Ginkgo leaves, extracts, phytopharmaceuticals and some herbal supplements is comprehensively reviewed. The review is an update of a similar, earlier review in this journal [T.A. van Beek, J. Chromatogr. A 967 (2002) 21-55]. Since 2001 over 3000 papers on Ginkgo biloba have appeared, and about 400 of them pertain to chemical analysis in a broad sense and are cited herein. The more important ones are discussed and, where relevant, compared with the best methods published prior to 2002. In the same period over 2500 patents were filed on Ginkgo and the very few related to analysis are mentioned as well. Important constituents include terpene trilactones, i.e. ginkgolide A, B, C, J and bilobalide, flavonol glycosides, biflavones, proanthocyanidins, alkylphenols, simple phenolic acids, 6-hydroxykynurenic acid, 4-O-methylpyridoxine and polyprenols. In the most common so-called "standardised" Ginkgo extracts and phytopharmaceuticals several of these classes are no longer present. About 130 new papers deal with the analysis of the terpene trilactones. They are mostly extracted with methanol or water or mixtures thereof. Supercritical fluid extraction and pressurised water extraction are also possible. Sample clean-up is mostly by liquid-liquid extraction with ethyl acetate although no sample clean-up at all in combination with LC/MS/MS is gaining in importance. Separation and detection can be routinely carried out by RP-HPLC with ELSD, RI or MS, or by GC/FID or GC/MS after silylation. Hydrolysis followed by LC/MS allows the simultaneous analysis of terpene trilactones and flavonol aglycones. No quantitative procedure for all major flavonol glycosides has yet been published because they are not commercially available. The quantitation of a few available glycosides has been carried out but does not serve a real purpose. After acidic hydrolysis to the aglycones quercetin, kaempferol and isorhamnetin and separation by HPLC

  14. Dynamic Processes of Conceptual Change: Analysis of Constructing Mental Models of Chemical Equilibrium.

    Science.gov (United States)

    Chiu, Mei-Hung; Chou, Chin-Cheng; Liu, Chia-Ju

    2002-01-01

    Investigates students' mental models of chemical equilibrium using dynamic science assessments. Reports that students at various levels have misconceptions about chemical equilibrium. Involves 10th grade students (n=30) in the study doing a series of hands-on chemical experiments. Focuses on the process of constructing mental models, dynamic…

  15. An Inventory for Measuring Student Teachers' Knowledge of Chemical Representations: Design, Validation, and Psychometric Analysis

    Science.gov (United States)

    Taskin, V.; Bernholt, S.; Parchmann, I.

    2015-01-01

    Chemical representations play an important role in helping learners to understand chemical contents. Thus, dealing with chemical representations is a necessity for learning chemistry, but at the same time, it presents a great challenge to learners. Due to this great challenge, it is not surprising that numerous national and international studies…

  16. Time-series metagenomic analysis reveals robustness of soil microbiome against chemical disturbance.

    Science.gov (United States)

    Kato, Hiromi; Mori, Hiroshi; Maruyama, Fumito; Toyoda, Atsushi; Oshima, Kenshiro; Endo, Ryo; Fuchu, Genki; Miyakoshi, Masatoshi; Dozono, Ayumi; Ohtsubo, Yoshiyuki; Nagata, Yuji; Hattori, Masahira; Fujiyama, Asao; Kurokawa, Ken; Tsuda, Masataka

    2015-12-01

    Soil microbial communities have great potential for bioremediation of recalcitrant aromatic compounds. However, it is unclear which taxa and genes in the communities, and how they contribute to the bioremediation in the polluted soils. To get clues about this fundamental question here, time-course (up to 24 weeks) metagenomic analysis of microbial community in a closed soil microcosm artificially polluted with four aromatic compounds, including phenanthrene, was conducted to investigate the changes in the community structures and gene pools. The pollution led to drastic changes in the community structures and the gene sets for pollutant degradation. Complete degradation of phenanthrene was strongly suggested to occur by the syntrophic metabolism by Mycobacterium and the most proliferating genus, Burkholderia. The community structure at Week 24 (∼12 weeks after disappearance of the pollutants) returned to the structure similar to that before pollution. Our time-course metagenomic analysis of phage genes strongly suggested the involvement of the 'kill-the-winner' phenomenon (i.e. phage predation of Burkholderia cells) for the returning of the microbial community structure. The pollution resulted in a decrease in taxonomic diversity and a drastic increase in diversity of gene pools in the communities, showing the functional redundancy and robustness of the communities against chemical disturbance.

  17. Two-dimensional linear discriminant analysis for classification of three-way chemical data.

    Science.gov (United States)

    Silva, Adenilton C da; Soares, Sófacles F C; Insausti, Matías; Galvão, Roberto K H; Band, Beatriz S F; Araújo, Mário César U de

    2016-09-28

    The two-dimensional linear discriminant analysis (2D-LDA) algorithm was originally proposed in the context of face image processing for the extraction of features with maximal discriminant power. However, despite its promising performance in image processing tasks, the 2D-LDA algorithm has not yet been used in applications involving chemical data. The present paper bridges this gap by investigating the use of 2D-LDA in classification problems involving three-way spectral data. The investigation was concerned with simulated data, as well as real-life data sets involving the classification of dry-cured Parma ham according to ageing by surface autofluorescence spectrometry and the classification of edible vegetable oils according to feedstock using total synchronous fluorescence spectrometry. The results were compared with those obtained by using the spectral data with no feature extraction, U-PLS-DA (Partial Least Squares Discriminant Analysis applied to the unfolded data), and LDA employing TUCKER-3 or PARAFAC scores. In the simulated data set, all methods yielded a correct classification rate of 100%. However, in the Parma ham and vegetable oil data sets, better classification rates were obtained by using 2D-LDA (86% and 100%), compared with no feature extraction (76% and 77%), U-PLS-DA (81% and 92%), PARAFAC-LDA (76% and 86%) and TUCKER3-LDA (86% and 93%). PMID:27619086

  18. Miniature Variable Pressure Scanning Electron Microscope for In-Situ Imaging and Chemical Analysis

    Science.gov (United States)

    Gaskin, Jessica A.; Jerman, Gregory; Gregory, Don; Sampson, Allen R.

    2012-01-01

    NASA Marshall Space Flight Center (MSFC) is leading an effort to develop a Miniaturized Variable Pressure Scanning Electron Microscope (MVP-SEM) for in-situ imaging and chemical analysis of uncoated samples. This instrument development will be geared towards operation on Mars and builds on a previous MSFC design of a mini-SEM for the moon (funded through the NASA Planetary Instrument Definition and Development Program). Because Mars has a dramatically different environment than the moon, modifications to the MSFC lunar mini-SEM are necessary. Mainly, the higher atmospheric pressure calls for the use of an electron gun that can operate at High Vacuum, rather than Ultra-High Vacuum. The presence of a CO2-rich atmosphere also allows for the incorporation of a variable pressure system that enables the in-situ analysis of nonconductive geological specimens. Preliminary testing of Mars meteorites in a commercial Environmental SEM(Tradmark) (FEI) confirms the usefulness of lowcurrent/low-accelerating voltage imaging and highlights the advantages of using the Mars atmosphere for environmental imaging. The unique capabilities of the MVP-SEM make it an ideal tool for pursuing key scientific goals of NASA's Flagship Mission Max-C; to perform in-situ science and collect and cache samples in preparation for sample return from Mars.

  19. GC-FID coupled with chemometrics for quantitative and chemical fingerprinting analysis of Alpinia oxyphylla oil.

    Science.gov (United States)

    Miao, Qing; Kong, Weijun; Zhao, Xiangsheng; Yang, Shihai; Yang, Meihua

    2015-01-01

    Analytical methods for quantitative analysis and chemical fingerprinting of volatile oils from Alpinia oxyphylla were established. The volatile oils were prepared by hydrodistillation, and the yields were between 0.82% and 1.33%. The developed gas chromatography-flame ionization detection (GC-FID) method showed good specificity, linearity, reproducibility, stability and recovery, and could be used satisfactorily for quantitative analysis. The results showed that the volatile oils contained 2.31-77.30 μL/mL p-cymene and 12.38-99.34 mg/mL nootkatone. A GC-FID fingerprinting method was established, and the profiles were analyzed using chemometrics. GC-MS was used to identify the principal compounds in the GC-FID profiles. The profiles of almost all the samples were consistent and stable. The harvesting time and source were major factors that affected the profile, while the volatile oil yield and the nootkatone content had minor secondary effects. PMID:25459943

  20. Comprehensive chemical analysis of Schisandra chinensis by HPLC-DAD-MS combined with chemometrics.

    Science.gov (United States)

    Liu, Haitao; Lai, Hongwu; Jia, Xinyue; Liu, Jiushi; Zhang, Zhao; Qi, Yaodong; Zhang, Jin; Song, Junbin; Wu, Chongming; Zhang, Bengang; Xiao, Peigen

    2013-09-15

    The fruit of Schisandra chinensis, namely "Wuweizi" in China, is a well-known herbal medicine and health food. In this paper, an accurate and reliable high performance liquid chromatography coupled with diode array detection and mass spectrometry was developed for quality evaluation of Wuweizi. Nine lignans, including schisandrol A, schisandrol B, angeloylgomisin H, gomisin G, schisantherin A, schisanhenol, schisandrin A, schisandrin B, and schisandrin C were determined simultaneously in forty-three batches of Wuweizi samples collected from different localities. Thirty-six common peaks were unequivocally identified or tentatively assigned by comparing their mass spectrometric data with reference compounds, self-established compound library and published literatures. And the thirty-six common peaks were selected as characteristic peaks to assess the similarity of chromatographic fingerprinting of these Wuweizi samples. Moreover, hierarchical clustering analysis and principal components analysis were successfully applied to demonstrate the variability of these Wuweizi samples. The results indicated the content of nine investigated lignans varied greatly among the samples, and samples collected from different localities could be discriminated. Furthermore, schisandrol A, schisandrol B, schisandrin B, and schisandrin C were found to chemical marker for evaluating the quality of Wuweizi.

  1. Neutron activation analysis for assessing chemical composition of dry dog foods

    International Nuclear Information System (INIS)

    Brazil holds the second largest population of domestic dogs in the world, with 33 million dogs, only behind the United States. The annual consumption of dog food in the country is 1.75 million tons, corresponding to the World's sixth in trade turnover. Dog food is supposed to be a complete and balanced diet, formulated with high quality ingredients. All nutrients and minerals required for an adequate nutrition of dogs are added to the formulation to ensure longevity and welfare. In this context, the present study aimed at assessing the chemical composition of dry dog foods commercialized in Brazil. Thirty-four samples were acquired in the local market of Piracicaba and analyzed by instrumental neutron activation analysis (INAA) to determine the elements As, Br, Ca, Co, Cr, Cs, Fe, K, La, Na, Rb, Sb, Sc, Se, U, and Zn. In general, the concentrations of Ca, Fe, K, Na, and Zn complied with the values required by the Association of American Feed Control Officials (AAFCO). To evaluate the safety of dog food commercialized in Brazil, further investigation is necessary to better understand the presence of toxic elements found in this study, i.e. Sb and U. INAA was useful for the screening analysis of different types and brands of dry dog foods for the determination of both essential and toxic elements. (author)

  2. Analysis of the multiple system with chemically peculiar component φ Draconis

    Science.gov (United States)

    Liška, J.

    2016-09-01

    The star ϕ Dra comprises a spectroscopic binary and a third star that together form a visual triple system. It is one of the brightest chemically peculiar stars of the upper main sequence. Despite these facts, no comprehensive study of its multiplicity has been performed yet. In this work, we present a detailed analysis of the triple system based on available measurements. We use radial velocities taken from four sources in the literature in a re-analysis of the inner spectroscopic binary (Aab). An incorrect value of the orbital period of the inner system Aab about 27 d was accepted in literature more than 40 yr. A new solution of orbit with the 128-d period was determined. Relative position measurements of the outer visual binary system (AB) from Washington Double Star Catalog were compared with known orbital models. Furthermore, it was shown that astrometric motion in system AB is well described by the model of Andrade with a 308-yr orbital period. Parameters of A and B components were utilized to estimate individual brightness for all components and their masses from evolutionary tracks. Although we found several facts which support the gravitational bond between them, unbound solution cannot be fully excluded yet.

  3. Quantum chemical analysis of binary and ternary ferromagnetic alloys; Quantenchemische Untersuchungen binaerer und ternaerer ferromagnetischer Legierungen

    Energy Technology Data Exchange (ETDEWEB)

    Jacobs, Yasemin Erika Charlotte

    2007-02-23

    In this work the electronic structures, densities of states, chemical bonding, magnetic exchange Parameters and Curie temperatures of binary and ternary ferromagnetic alloys are analyzed. The electronic structure of ferromagnetic MnAl has been calculated using density-functional techniques (TB-LMTO-ASA, FPLAPW) and quantum chemically analyzed by means of the crystal orbital Hamilton population analysis. The crystal structure of the ferromagnetic tetragonal MnAl may be understood to originate from the structure of nonmagnetic cubic MnAl with a CsCl motif through a two-step process. While the nonmagnetic cubic structure is stable against a structural deformation, antibonding Mn-Mn interactions at the Fermi level lead to spin polarization and the onset of magnetism, i.e., a symmetry reduction taking place solely in the electronic degrees of freedom, by that emptying antibonding Mn-Mn states. Residual antibonding Al--Al states can only be removed by a subsequent, energetically smaller structural deformation towards the tetragonal system. As a final result, homonuclear bonding is strengthened and heteronuclear bonding is weakened. Corresponding DFT calculations of the electronic structure as well as the calculation of the chemical bonding and the magnetic exchange interactions have been performed on the basis of LDA and GGA for a series of ferromagnetic full Heusler alloys of general formula Co2MnZ (Z=Ga,Si,Ge,Sn), Rh2MnZ (Z=Ge,Sn,Pb), Ni2MnZ (Z=Ga,In,Sn), Pd2MnZ (Z=Sn,Sb) and Cu2MnZ (Z=Al,In,Sn). The connection between the electronic spectra and the magnetic interactions have been studied. Correlations between the chemical bondings in Heusler alloys derived from COHP analysis and magnetic phenomena are obvious, and different mechanisms leading to spin polarization and ferromagnetism are derived. The band dependence of the exchange parameters, their dependence on volume and valence electron concentration have been thoroughly analyzed within the Green function technique

  4. Chemical analysis of simulated high level waste glasses to support stage III sulfate solubility modeling

    Energy Technology Data Exchange (ETDEWEB)

    Fox, K. M. [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL)

    2016-03-17

    The U.S. Department of Energy (DOE), Office of Environmental Management (EM) is sponsoring an international, collaborative project to develop a fundamental model for sulfate solubility in nuclear waste glass. The solubility of sulfate has a significant impact on the achievable waste loading for nuclear waste forms within the DOE complex. These wastes can contain relatively high concentrations of sulfate, which has low solubility in borosilicate glass. This is a significant issue for low-activity waste (LAW) glass and is projected to have a major impact on the Hanford Tank Waste Treatment and Immobilization Plant (WTP). Sulfate solubility has also been a limiting factor for recent high level waste (HLW) sludge processed at the Savannah River Site (SRS) Defense Waste Processing Facility (DWPF). The low solubility of sulfate in glass, along with melter and off-gas corrosion constraints, dictate that the waste be blended with lower sulfate concentration waste sources or washed to remove sulfate prior to vitrification. The development of enhanced borosilicate glass compositions with improved sulfate solubility will allow for higher waste loadings and accelerate mission completion.The objective of the current scope being pursued by SHU is to mature the sulfate solubility model to the point where it can be used to guide glass composition development for DWPF and WTP, allowing for enhanced waste loadings and waste throughput at these facilities. A series of targeted glass compositions was selected to resolve data gaps in the model and is identified as Stage III. SHU fabricated these glasses and sent samples to SRNL for chemical composition analysis. SHU will use the resulting data to enhance the sulfate solubility model and resolve any deficiencies. In this report, SRNL provides chemical analyses for the Stage III, simulated HLW glasses fabricated by SHU in support of the sulfate solubility model development.

  5. Chemical analysis of simulated high level waste glasses to support stage III sulfate solubility modeling

    International Nuclear Information System (INIS)

    The U.S. Department of Energy (DOE), Office of Environmental Management (EM) is sponsoring an international, collaborative project to develop a fundamental model for sulfate solubility in nuclear waste glass. The solubility of sulfate has a significant impact on the achievable waste loading for nuclear waste forms within the DOE complex. These wastes can contain relatively high concentrations of sulfate, which has low solubility in borosilicate glass. This is a significant issue for low-activity waste (LAW) glass and is projected to have a major impact on the Hanford Tank Waste Treatment and Immobilization Plant (WTP). Sulfate solubility has also been a limiting factor for recent high level waste (HLW) sludge processed at the Savannah River Site (SRS) Defense Waste Processing Facility (DWPF). The low solubility of sulfate in glass, along with melter and off-gas corrosion constraints, dictate that the waste be blended with lower sulfate concentration waste sources or washed to remove sulfate prior to vitrification. The development of enhanced borosilicate glass compositions with improved sulfate solubility will allow for higher waste loadings and accelerate mission completion.The objective of the current scope being pursued by SHU is to mature the sulfate solubility model to the point where it can be used to guide glass composition development for DWPF and WTP, allowing for enhanced waste loadings and waste throughput at these facilities. A series of targeted glass compositions was selected to resolve data gaps in the model and is identified as Stage III. SHU fabricated these glasses and sent samples to SRNL for chemical composition analysis. SHU will use the resulting data to enhance the sulfate solubility model and resolve any deficiencies. In this report, SRNL provides chemical analyses for the Stage III, simulated HLW glasses fabricated by SHU in support of the sulfate solubility model development.

  6. Analysis of Pore Pressure and Stress Distribution around a Wellbore Drilled in Chemically Active Elastoplastic Formations

    Science.gov (United States)

    Roshan, Hamid; Rahman, S. S.

    2011-09-01

    Drilling in low-permeable reactive shale formations with water-based drilling mud presents significant challenges, particularly in high-pressure and high-temperature environments. In previous studies, several models were proposed to describe the thermodynamic behaviour of shale. Most shale formations under high pressure are expected to undergo plastic deformation. An innovative algorithm including work hardening is proposed in the framework of thermo-chemo-poroelasticity to investigate the effect of plasticity on stresses around the wellbore. For this purpose a finite-element model of coupled thermo-chemo-poro-elastoplasticity is developed. The governing equations are based on the concept of thermodynamics of irreversible processes in discontinuous systems. In order to solve the plastic problem, a single-step backward Euler algorithm containing a yield surface-correction scheme is used to integrate the plastic stress-strain relation. An initial stress method is employed to solve the non-linearity of the plastic equation. In addition, super convergent patch recovery is used to accurately evaluate the time-dependent stress tensor from nodal displacement. The results of this study reveal that thermal and chemical osmosis can significantly affect the fluid flow in low-permeable shale formations. When the salinity of drilling mud is higher than that of pore fluid, fluid is pulled out of the formation by chemical osmotic back flow. Similar results are observed when the temperature of drilling mud is lower than that of the formation fluid. It is found that linear elastic approaches to wellbore stability analysis appear to overestimate the tangential stress around the wellbore and produce more conservative stresses compared to the results of field observation. Therefore, the drilling mud properties obtained from the elastoplastic wellbore stability in shales provide a safer mud weight window and reduce drilling cost.

  7. Dissociative electron transfer in polychlorinated aromatics. Reduction potentials from convolution analysis and quantum chemical calculations.

    Science.gov (United States)

    Romańczyk, Piotr P; Rotko, Grzegorz; Kurek, Stefan S

    2016-08-10

    Formal potentials of the first reduction leading to dechlorination in dimethylformamide were obtained from convolution analysis of voltammetric data and confirmed by quantum chemical calculations for a series of polychlorinated benzenes: hexachlorobenzene (-2.02 V vs. Fc(+)/Fc), pentachloroanisole (-2.14 V), and 2,4-dichlorophenoxy- and 2,4,5-trichlorophenoxyacetic acids (-2.35 V and -2.34 V, respectively). The key parameters required to calculate the reduction potential, electron affinity and/or C-Cl bond dissociation energy, were computed at both DFT-D and CCSD(T)-F12 levels. Comparison of the obtained gas-phase energies and redox potentials with experiment enabled us to verify the relative energetics and the performance of various implicit solvent models. Good agreement with the experiment was achieved for redox potentials computed at the DFT-D level, but only for the stepwise mechanism owing to the error compensation. For the concerted electron transfer/C-Cl bond cleavage process, the application of a high level coupled cluster method is required. Quantum chemical calculations have also demonstrated the significant role of the π*ring and σ*C-Cl orbital mixing. It brings about the stabilisation of the non-planar, C2v-symmetric C6Cl6˙(-) radical anion, explains the experimentally observed low energy barrier and the transfer coefficient close to 0.5 for C6Cl5OCH3 in an electron transfer process followed by immediate C-Cl bond cleavage in solution, and an increase in the probability of dechlorination of di- and trichlorophenoxyacetic acids due to substantial population of the vibrational excited states corresponding to the out-of-plane C-Cl bending at ambient temperatures. PMID:27477334

  8. Group Analysis of Free Convection Flow of a Magnetic Nanofluid with Chemical Reaction

    Directory of Open Access Journals (Sweden)

    Md. Jashim Uddin

    2015-01-01

    Full Text Available A theoretical study of two-dimensional magnetohydrodynamics viscous incompressible free convective boundary layer flow of an electrically conducting, chemically reacting nanofluid from a convectively heated permeable vertical surface is presented. Scaling group of transformations is used in the governing equations and the boundary conditions to determine absolute invariants. A third-order ordinary differential equation which corresponds to momentum conservation and two second-order ordinary differential equations which correspond to energy and nanoparticle volume fraction (species conservation are derived. Our (group analysis indicates that, for the similarity solution, the convective heat transfer coefficient and mass transfer velocity are proportional to x-1/4 whilst the reaction rate is proportional to x-1/2, where x is the axial distance from the leading edge of the plate. The effects of the relevant controlling parameters on the dimensionless velocity, temperature, and nanoparticle volume fraction are examined. The accuracy of the technique we have used was tested by performing comparisons with the results of published work and the results were found to be in good agreement. The present computations indicate that the flow is accelerated and temperature enhanced whereas nanoparticle volume fractions are decreased with increasing order of chemical reaction. Furthermore the flow is strongly decelerated, whereas the nanoparticle volume fraction and temperature are enhanced with increasing magnetic field parameter. Increasing convection-conduction parameter increases velocity and temperatures but has a weak influence on nanoparticle volume fraction distribution. The present study demonstrates the thermal enhancement achieved with nanofluids and also magnetic fields and is of relevance to nanomaterials processing.

  9. Dissociative electron transfer in polychlorinated aromatics. Reduction potentials from convolution analysis and quantum chemical calculations.

    Science.gov (United States)

    Romańczyk, Piotr P; Rotko, Grzegorz; Kurek, Stefan S

    2016-08-10

    Formal potentials of the first reduction leading to dechlorination in dimethylformamide were obtained from convolution analysis of voltammetric data and confirmed by quantum chemical calculations for a series of polychlorinated benzenes: hexachlorobenzene (-2.02 V vs. Fc(+)/Fc), pentachloroanisole (-2.14 V), and 2,4-dichlorophenoxy- and 2,4,5-trichlorophenoxyacetic acids (-2.35 V and -2.34 V, respectively). The key parameters required to calculate the reduction potential, electron affinity and/or C-Cl bond dissociation energy, were computed at both DFT-D and CCSD(T)-F12 levels. Comparison of the obtained gas-phase energies and redox potentials with experiment enabled us to verify the relative energetics and the performance of various implicit solvent models. Good agreement with the experiment was achieved for redox potentials computed at the DFT-D level, but only for the stepwise mechanism owing to the error compensation. For the concerted electron transfer/C-Cl bond cleavage process, the application of a high level coupled cluster method is required. Quantum chemical calculations have also demonstrated the significant role of the π*ring and σ*C-Cl orbital mixing. It brings about the stabilisation of the non-planar, C2v-symmetric C6Cl6˙(-) radical anion, explains the experimentally observed low energy barrier and the transfer coefficient close to 0.5 for C6Cl5OCH3 in an electron transfer process followed by immediate C-Cl bond cleavage in solution, and an increase in the probability of dechlorination of di- and trichlorophenoxyacetic acids due to substantial population of the vibrational excited states corresponding to the out-of-plane C-Cl bending at ambient temperatures.

  10. Quantitative Chemical Analysis of Archaeological Slag Material Using Handheld X-ray Fluorescence Spectrometry.

    Science.gov (United States)

    Scott, Rebecca B; Eekelers, Kim; Degryse, Patrick

    2016-01-01

    Handheld X-ray fluorescence spectrometry (XRF) has seen a dramatic increase in use for archaeological projects. The attraction of the technique is its portable and nondestructive nature. In many cases, the archaeological artefacts in question cannot be destructively sampled, or the piece itself cannot be sent to an analytical laboratory. One of the current research interests associated with the Sagalassos project is the study of the Roman iron industry. Previously exported iron slag and ore from the site and the surrounding area was subjected to laboratory chemical analyses. These indicated that different ores were being utilized in the production of iron in different periods. In order to further the project the slag material still in the site depot needed to be analyzed. However, recent legislative changes mean that materials can only be analyzed on-site. Since samples could not be taken and destructive chemical analysis was no longer feasible, a portable, nondestructive technique was required. Handheld XRF can easily provide qualitative data, but these data are only comparable to other handheld XRF qualitative data, from the same device. Quantitative data gathering is possible, but can be more problematic, particularly when the material in question is heterogeneous in nature. A calibration file was created using the manufacturer's software and "in-house" standards made from the pre-quantified samples of iron slag available in the laboratory. In order to make the calibration as robust as possible, the composition of the standards was analyzed statistically to determine which of these created bias and leverage for specific elements. These standards were then omitted from the calibration for that element. The calibration was tested in the laboratory using samples of iron slag previously analyzed with wet chemistry, and the results indicated that most sample analyses showed 30% error were found in samples which contained very low or very high quantities of the

  11. Analysis of the Engineering Restoration Effect of Abandoned Yongledian Quarry in Beijing City Based on Soil Physical and Chemical Properties

    Institute of Scientific and Technical Information of China (English)

    Liwei; CAI

    2014-01-01

    The improvement of the soil physical and chemical properties is the most important foundation for mine ecological restoration.The experiment is aimed at undisturbed area,restored area,and damaged area of abandoned Yongledian Quarry in Beijing.Through determination and analysis of soil physical and chemical properties,it shows that there are significant differences in the composite effects of soil physical and chemical properties between restored area,and undisturbed area,damaged area,and engineering restoration effectively improves the composite effects of soil physical and chemical properties in the restored area.The single factor hypothesis test shows that soil pH value,organic matter,alkali-hydrolyzable nitrogen,and total nitrogen traits are the key targets to be restored in this mining area.

  12. LSENS: A General Chemical Kinetics and Sensitivity Analysis Code for homogeneous gas-phase reactions. Part 3: Illustrative test problems

    Science.gov (United States)

    Bittker, David A.; Radhakrishnan, Krishnan

    1994-01-01

    LSENS, the Lewis General Chemical Kinetics and Sensitivity Analysis Code, has been developed for solving complex, homogeneous, gas-phase chemical kinetics problems and contains sensitivity analysis for a variety of problems, including nonisothermal situations. This report is part 3 of a series of three reference publications that describe LSENS, provide a detailed guide to its usage, and present many example problems. Part 3 explains the kinetics and kinetics-plus-sensitivity analysis problems supplied with LSENS and presents sample results. These problems illustrate the various capabilities of, and reaction models that can be solved by, the code and may provide a convenient starting point for the user to construct the problem data file required to execute LSENS. LSENS is a flexible, convenient, accurate, and efficient solver for chemical reaction problems such as static system; steady, one-dimensional, inviscid flow; reaction behind incident shock wave, including boundary layer correction; and perfectly stirred (highly backmixed) reactor. In addition, the chemical equilibrium state can be computed for the following assigned states: temperature and pressure, enthalpy and pressure, temperature and volume, and internal energy and volume. For static problems the code computes the sensitivity coefficients of the dependent variables and their temporal derivatives with respect to the initial values of the dependent variables and/or the three rate coefficient parameters of the chemical reactions.

  13. Applying Chemical Imaging Analysis to Improve Our Understanding of Cold Cloud Formation

    Science.gov (United States)

    Laskin, A.; Knopf, D. A.; Wang, B.; Alpert, P. A.; Roedel, T.; Gilles, M. K.; Moffet, R.; Tivanski, A.

    2012-12-01

    The impact that atmospheric ice nucleation has on the global radiation budget is one of the least understood problems in atmospheric sciences. This is in part due to the incomplete understanding of various ice nucleation pathways that lead to ice crystal formation from pre-existing aerosol particles. Studies investigating the ice nucleation propensity of laboratory generated particles indicate that individual particle types are highly selective in their ice nucleating efficiency. This description of heterogeneous ice nucleation would present a challenge when applying to the atmosphere which contains a complex mixture of particles. Here, we employ a combination of micro-spectroscopic and optical single particle analytical methods to relate particle physical and chemical properties with observed water uptake and ice nucleation. Field-collected particles from urban environments impacted by anthropogenic and marine emissions and aging processes are investigated. Single particle characterization is provided by computer controlled scanning electron microscopy with energy dispersive analysis of X-rays (CCSEM/EDX) and scanning transmission X-ray microscopy with near edge X-ray absorption fine structure spectroscopy (STXM/NEXAFS). A particle-on-substrate approach coupled to a vapor controlled cooling-stage and a microscope system is applied to determine the onsets of water uptake and ice nucleation including immersion freezing and deposition ice nucleation as a function of temperature (T) as low as 200 K and relative humidity (RH) up to water saturation. We observe for urban aerosol particles that for T > 230 K the oxidation level affects initial water uptake and that subsequent immersion freezing depends on particle mixing state, e.g. by the presence of insoluble particles. For T cloud formation. Initial results applying single particle IN analysis using CCSEM/EDX and STXM/NEXAFS reveal that a significant amount of IN are coated by organics and, thus, are similar to the

  14. Laser-based mass spectrometry for in situ chemical composition analysis of planetary surfaces

    Science.gov (United States)

    Frey, Samira; Neuland, Maike B.; Grimaudo, Valentine; Moreno-García, Pavel; Riedo, Andreas; Tulej, Marek; Broekmann, Peter; Wurz, Peter

    2016-04-01

    Mass spectrometry is an important analytical technique in space research. The chemical composition of planetary surface material is a key scientific question on every space mission to a planet, moon or asteroid. Chemical composition measurements of rocky material on the surface are of great importance to understand the origin and evolution of the planetary body.[1] A miniature laser ablation/ionisation reflectron- type time-of-flight mass spectrometer (instrument name LMS) was designed and built at the University of Bern for planetary research.[2] Despite its small size and light weight, the LMS instrument still maintains the same capabilities as large laboratory systems, which makes it suitable for its application on planetary space missions.[3-5] The high dynamic range of about eight orders of magnitude, high lateral (μm-level) and vertical (sub-nm level) resolution and high detection sensitivity for almost all elements (10 ppb, atomic fraction) make LMS a versatile instrument for various applications. LMS is a suitable instrument for in situ measurements of elemental and isotope composition with high precision and accuracy. Measurements of Pb- isotope abundances can be used for dating of planetary material. Measurements of bio-relevant elements allow searching for past or present life on a planetary surface. The high spatial resolution, both in lateral and vertical direction, is of considerable interest, e.g. for analysis of inhomogeneous, extraterrestrial samples as well as weathering processes of planetary material. References [1] P. Wurz, D. Abplanalp, M. Tulej, M. Iakovleva, V.A. Fernandes, A. Chumikov, and G. Managadze, "Mass Spectrometric Analysis in Planetary Science: Investigation of the Surface and the Atmosphere", Sol. Sys. Res., 2012, 46, 408. [2] U. Rohner, J.A. Whitby, P. Wurz, "A miniature laser ablation time of flight mass spectrometer for in situ planetary exploration" Meas. Sci. Tch., 2003, 14, 2159. [3] M. Tulej, A. Riedo, M.B. Neuland, S

  15. Computational analysis of the mechanism of chemical reactions in terms of reaction phases: hidden intermediates and hidden transition States.

    Science.gov (United States)

    Kraka, Elfi; Cremer, Dieter

    2010-05-18

    Computational approaches to understanding chemical reaction mechanisms generally begin by establishing the relative energies of the starting materials, transition state, and products, that is, the stationary points on the potential energy surface of the reaction complex. Examining the intervening species via the intrinsic reaction coordinate (IRC) offers further insight into the fate of the reactants by delineating, step-by-step, the energetics involved along the reaction path between the stationary states. For a detailed analysis of the mechanism and dynamics of a chemical reaction, the reaction path Hamiltonian (RPH) and the united reaction valley approach (URVA) are an efficient combination. The chemical conversion of the reaction complex is reflected by the changes in the reaction path direction t(s) and reaction path curvature k(s), both expressed as a function of the path length s. This information can be used to partition the reaction path, and by this the reaction mechanism, of a chemical reaction into reaction phases describing chemically relevant changes of the reaction complex: (i) a contact phase characterized by van der Waals interactions, (ii) a preparation phase, in which the reactants prepare for the chemical processes, (iii) one or more transition state phases, in which the chemical processes of bond cleavage and bond formation take place, (iv) a product adjustment phase, and (v) a separation phase. In this Account, we examine mechanistic analysis with URVA in detail, focusing on recent theoretical insights (with a variety of reaction types) from our laboratories. Through the utilization of the concept of localized adiabatic vibrational modes that are associated with the internal coordinates, q(n)(s), of the reaction complex, the chemical character of each reaction phase can be identified via the adiabatic curvature coupling coefficients, A(n,s)(s). These quantities reveal whether a local adiabatic vibrational mode supports (A(n,s) > 0) or resists

  16. Minimizing chemical interference errors for the determination of lithium in brines by flame atomic absorption spectroscopy analysis

    Institute of Scientific and Technical Information of China (English)

    WEN Xianming; MA Peihua; ZHU Geqin; WU Zhiming

    2006-01-01

    Chemical interferences (ionization and oxide/hydroxide formation) on the atomic absorbance signal of lithium in FAAS analysis of brine samples are elaborated in this article. It is suggested that inadequate or overaddition of deionization buffers can lead to loss of sensitivities under particular operating conditions. In the analysis of brine samples, signal enhancing and oxide/hydroxide formation inducing signal reduction resulting from overaddition of deionization buffers can be seen with varying amounts of chemical buffers. Based on experimental results, the authors have arrived at the op timized operating conditions for the detection of lithium, under which both ionization and stable compound formation can be suppressed. This is a simplified and quick method with adequate accuracy and precision for the determination of lithium in routine brine samples from chemical plants or R&D laboratories, which contain comparable amounts of lithium with some other components.

  17. ANALYSIS OF MACRO AND MICROELEMENTS IN TEETH, SALIVA, AND BLOOD OF WORKERS IN FERGANA CHEMICAL PLANT OF FURAN COMPOUNDS

    Directory of Open Access Journals (Sweden)

    Sunnatillo Gaffarov

    2014-11-01

    Full Text Available This article aims to share the results of research conducted in the Fergana chemical plant of furan compounds (FCPFC in Uzbekistan.19 workers of the Furan compounds plant, in Fergana, Uzbekistan, were tested. By neutron activation analysis method, we have studied microelement composition of saliva, blood, dental hard tissue, and the level of Ca, Zn, Fe, and Ag in these subjects. We havedetected that the level of chemical elements in dental hard tissue, blood, and saliva of these workers was subject to negative changes as compared to the analysis results from those in the control group.The research results havepractical value for the prophylaxis, treatment, and health resumption of the people living in rugged ecological environment and workers who are engagedwith harmful substances in chemical industry.  Furthermore,this research also provides recommendations fortreatment of dental diseases related to common conditions of pathophysiological processes carried out bylivingorganisms.

  18. ANALYSIS OF CHEMICAL COMPOUNDS OF AGARWOOD OIL FROM DIFFERENT SPECIES BY GAS CHROMATOGRAPHY MASS SPECTROMETRY (GCMS

    Directory of Open Access Journals (Sweden)

    Yumi Zuhanis Has-Yun Hashim

    2014-05-01

    Full Text Available ABSTRACT: Agarwood oil is a highly prized type of oil due to its unique aroma. The oil is extracted from the fragrant resin found in the agarwood tree (trunk.  The unique aroma and quality of agarwood resin and oil are contributed by the presence of certain chemical compounds. In this work, analysis and comparison of the chemical compounds of agarwood oil from A. malaccensis, A. sub-integra and a mixture of both were conducted.  The essential oils were diluted in hexane (5% prior to gas chromatography mass spectrometry (GCMS analysis performed using Agilent GCMS 7890A coupled with MSD quadrupole detector 5975 C.  Separation of analytes by gas chromatography was carried out using a Hewlett Packard HP-5MS silica capillary column (30 m X 0.25 mm X 0.25 mm. A total of 107 compounds were identified from the three samples of agarwood oils. Fifty-five (55 components were identified in A. malaccensis sample which contributes to the largest portion of the total compounds. About 20% of the compounds identified were aromatic and sesquiterpenes which have been revealed to be the main active compounds of agarwood oils which also give the aroma and pleasant odour of agarwood. Different compositions or profile of chemical components were found in agarwood oils from the two different species. Two compounds were commonly identified in all three samples namely 3-phenyl-2-butanone and alpha-cubebene.  Further studies are needed to refine the results which later can be used to assist detection and authentication of agarwood as well as its scientific-based grading. ABSTRAK: Minyak gaharu merupakan sejenis minyak beraroma unik yang mendapat permintaan tinggi dan mahal. Minyak ini diekstrak daripada resin beraroma yang terbentuk di dalam batang pokok gaharu. Keunikan aroma dan kualiti resin dan minyak gaharu ini bergantung kepada kehadiran bahan kimia tertentu. Penyelidikan ini menjurus kepada analisis dan perbandingan bahan-bahan kimia yang terdapat dalam minyak

  19. Constraints on the Global-scale Chemical Weathering State of Mars From TES Results Based on Spectral Analysis of Chemically Weathered Basalts

    Science.gov (United States)

    Michalski, J. R.; Kraft, M. D.; Sharp, T. G.; Christensen, P. R.

    2005-12-01

    mineralogy from thermal infrared data; weathering serves to bias igneous interpretations toward rocks of higher silica and alkali contents. Trends observed in the spectral analysis of chemically weathered CRBG rock surfaces could explain some of the spectral trends observed at Mars, suggesting that martian dark region basalts have been chemically weathered under consistently low-water, or only episodically wet surface conditions.

  20. Analysis of Some Physio-Chemical Properties of Milk Bush (Thevetia peruviana Seeds

    Directory of Open Access Journals (Sweden)

    O.M. Olatunji

    2011-02-01

    Full Text Available The proximate and some technological properties of milk bush (Thevetia peruviana seeds were investigated. The results obtained showed the following chemical compositions: Moisture content (2.94%, protein (7.44%, oil (57.05%, crude fibre (22.37%, ash (2:24 and carbohydrate by difference (7.76%. In the same vain, mineralogical analysis using an inductively coupled plasma atomic emission spectrometer was conducted. The results obtained showed that magnesium, potassium and sodium were the predominant elements in the seeds. The technological properties studied were unit mass, unit volume, geometric mean, diameter, sphericity, bulk density, true density and porosity with average values of 4.14 g, 4.403.57 mm3, 20.34 mm, 0.67, 657.73 kg/m3, 942.05 kg/m3 and 31%, respectively. Information of these properties could be useful in process machine design. On the other hand, knowledge of the proximate properties is important for nutritional and dietary information.

  1. PHYSICO CHEMICAL ANALYSIS OF PANCHAVAKTRA RAS: A HERBO-MINERAL FORMULATION

    Directory of Open Access Journals (Sweden)

    Bandari Srinivasulu

    2013-03-01

    Full Text Available Panchavaktra Ras is a rational combination of Rasadravyas and Kasthaushadhis prescribed in the management of Amavata. Panchavaktra rasa has been taken into consideration for its Pharmaceutical standardization through Standard Operative procedures. In pharmaceutical study, the drug has been prepared in 3 batches adopting Khalviya Rasayana method and physico chemical analysis was carried out on these batches. This formulation was analysed by using Inductively Coupled Plasma with Optical Emission Spectroscopy (ICPOES and found the major elements Hg, S, B, Fe, Cr, Cu, Ag, C, Pb, As from medicine. The heavy metals like As, Pb and Cd were almost within permissible limits. Organoleptic features of drug are found dark grey astringent taste and pungent odour which is made of the crude drugs within the standard range. The pH of compound was 8.93-8.99 and alkaline in nature. The phytochemical screening showed the presence of Alkaloids, Saponins, Flavanoids, Tanins and Tritepenoids in this drug. The Panchavaktra Ras was subjected to estimation of Microbial contamination which was within normal limits and it does not contain harmful microbes like Enterobacteriacea, E.coli, Salmonella species. Efforts have been made to fix the analytical standards of Panchavaktra ras, which were not found, reported till date.

  2. HE0107-5240, A Chemically Ancient Star.I. A Detailed Abundance Analysis

    CERN Document Server

    Christlieb, N; Korn, A J; Barklem, P S; Beers, T C; Bessell, M S; Karlsson, T; Mizuno-Wiedner, M

    2004-01-01

    We report a detailed abundance analysis for HE0107-5240, a halo giant with [Fe/H]_NLTE=-5.3. This star was discovered in the course of follow-up medium-resolution spectroscopy of extremely metal-poor candidates selected from the digitized Hamburg/ESO objective-prism survey. On the basis of high-resolution VLT/UVES spectra, we derive abundances for 8 elements (C, N, Na, Mg, Ca, Ti, Fe, and Ni), and upper limits for another 12 elements. A plane-parallel LTE model atmosphere has been specifically tailored for the chemical composition of {\\he}. Scenarios for the origin of the abundance pattern observed in the star are discussed. We argue that HE0107-5240 is most likely not a post-AGB star, and that the extremely low abundances of the iron-peak, and other elements, are not due to selective dust depletion. The abundance pattern of HE0107-5240 can be explained by pre-enrichment from a zero-metallicity type-II supernova of 20-25M_Sun, plus either self-enrichment with C and N, or production of these elements in the AG...

  3. Chemical Abundance Analysis of the Extremely Metal-Poor Star HE 1300+0157

    CERN Document Server

    Frebel, A; Aoki, W; Honda, S; Bessell, M S; Takada-Hidai, M; Beers, T C; Christlieb, N; Frebel, Anna; Norris, John E.; Aoki, Wako; Honda, Satoshi; Bessell, Michael S.; Takada-Hidai, Masahide; Beers, Timothy C.; Christlieb, Norbert

    2006-01-01

    We present a detailed chemical abundance analysis of HE 1300+0157, a subgiant with [Fe/H]=-3.9. From a high-resolution, high-S/N Subaru/HDS spectrum we find the star to be enriched in C ([C/Fe]_1D ~ +1.4) and O ([O/Fe]_1D ~ +1.8). With the exception of these species, HE 1300+0157 exhibits an elemental abundance pattern similar to that found in many other very and extremely metal-poor stars. The Li abundance is lower than the Spite-plateau value, in agreement with expectation for its evolutionary status. Of particular interest, no neutron-capture elements are detected in HE 1300+0157. This type of abundance pattern has been found by recent studies in several other metal-poor giants. We suggest that HE 1300+0157 is an unevolved example of this group of stars, which exhibit high C abundances together with low (or absent) abundances of neutron-capture elements. Several potential enrichment scenarios are presented. The low neutron-capture elements, including Sr, Ba, and Pb, suggests that the carbon excess observed...

  4. Preparation of polyethylene sacks for collection of precipitation samples for chemical analysis

    Science.gov (United States)

    Schroder, L.J.; Bricker, A.W.

    1985-01-01

    Polyethylene sacks are used to collect precipitation samples. Washing polyethylene with acetone, hexane, methanol, or nitric acid can change the adsorptive characteristics of the polyethylene. In this study, simulated precipitation at pH 4.5 was in contact with the polyethylene sacks for 21 days; subsamples were removed for chemical analysis at 7, 14, and 21 days after intitial contact. Sacks washed with acetone adsorbed iron and lithium; sacks washed with hexane adsorbed barium, iron , and lithium; sacks washed with methanol adsorbed calcium and iron; and sacks washed with 0.30 N nitric acid adsorbed iron. Leaching the plastic sacks with 0.15 N nitric acid did not result in 100-percent recovery of any of the adsorbed metals. Washing polyethylene sacks with dilute nitric acid caused the pH of the simulated precipitation to be decreased by 0.2 pH unit after 1 week of contact with the polyethylene. The specific conductance increased by 10 microsiemens per centimeter. Contamination of precipitation samples by lead was determined to be about 0.1 microgram per liter from contact with precleaned polyethylene sacks. No measurable contamination of precipitation samples by zinc occurred. (USGS)

  5. Analysis of chemical composition and bioactive property evaluation of Indian propolis

    Institute of Scientific and Technical Information of China (English)

    R Thirugnanasampandan; Sayana Beena Raveendran; R Jayakumar

    2012-01-01

    Objective: To analyze the chemical composition and to evaluate the bioactive potential of hydroalocoholic extract of propolis. Methods: Ethanol extract of propolis was analyzed by GC-MS, HPTLC and HPLC methods and in vitro antioxidant, anticholinesterase and cytotoxicity assay were performed. Results: GC-MS analysis revealed the presence of fatty acids, alcohols, and quercetin. Quercetin was identified and quantified by HPTLC and HPLC methods. Dose dependent DPPH and hydroxyl radical scavenging activity of hydroalcoholic extract of propolis was calculated as 16.20 and 34.33 μg/mL respectively. Inhibition of lipid peroxidation was significant and the IC50 value was calculated as 55.56μg/mL. Anticholinesterase activity was less observed. The cytotoxic activity against both breast (MCF-7) and lung cancer (A543) cell lines were significant and the IC50 value was calculated as 10 and 13 μg/mL respectively. Conclusions:These findings showed that bioactive compounds present in propolis will alleviate many diseases and can be used for better human health.

  6. Superconducting High-Resolution X-Ray Spectrometers for Chemical State Analysis of Dilute Samples

    International Nuclear Information System (INIS)

    Cryogenic X-ray spectrometers operating at temperatures below 1 K combine high energy resolution with broadband efficiency for X-ray energies up to 10 keV. They offer advantages for chemical state analysis of dilute samples by fluorescence-detected X-ray absorption spectroscopy (XAS) in cases where conventional Ge or Si(Li) detectors lack energy resolution and grating spectrometers lack detection efficiency. We are developing soft X-ray spectrometers based on superconducting Nb-Al-AlOx-Al-Nb tunnel junction (STJ) technology. X-rays absorbed in one of the superconducting electrodes generate excess charge carriers in proportion to their energy, thereby producing a measurable temporary increase in tunneling current. For STJ operation at the synchrotron, we have designed a two-stage adiabatic demagnetization refrigerator (ADR) with a cold finger that holds a 3 x 3 array of STJs inside the UHV sample chamber at a temperature of ∼0.1 K within ∼15 mm of a room temperature sample. Our STJ spectrometer can have an energy resolution below 10 eV FWHM for X-ray energies up to 1 keV, and has total count rate capabilities above 100,000 counts/s. We will describe detector performance in synchrotron-based X-ray fluorescence experiments and demonstrate its use for XAS on a dilute metal site in a metalloprotein

  7. Comparative physico-chemical, proximate and mineral analysis on raw and roasted seeds of groundnut

    Directory of Open Access Journals (Sweden)

    Bhanu Saravan Kumar

    2013-10-01

    Full Text Available Physico-chemical, proximate and nutritionally valuable minerals were determined aiming to compare raw and roasted groundnut seeds. The results indicated that total ash content of raw groundnut (4.6% was higher than the roasted groundnut (4.1% seeds. Crude protein content of roasted groundnut was higher (26.1% when compared to that of raw groundnut (24.9%. Crude carbohydrates levels of raw groundnut (25.3% are lower when compared with that of roasted groundnut (26.5%. Crude fat ranged from 39.1% in raw groundnut to 39.6% in roasted groundnut. Crude fiber percentage both in raw (2.9% and roasted (3.1% conditions were good. The moisture content of the raw groundnut (4.1% was more than the roasted groundnut (3.6% because of not exposure to heat. Seeds showed higher energy values both in raw and roasted conditions. Significant amount of minerals like potassium, calcium, magnesium, phosphorus, and zinc were present both in raw and roasted conditions. Based on statistical analysis the results showed highly significant differences (P < 0.05 between the raw and roasted seeds.

  8. Guidance on health effects of toxic chemicals. Safety Analysis Report Update Program

    Energy Technology Data Exchange (ETDEWEB)

    Foust, C.B.; Griffin, G.D.; Munro, N.B.; Socolof, M.L.

    1994-02-01

    Martin Marietta Energy Systems, Inc. (MMES), and Martin Marietta Utility Services, Inc. (MMUS), are engaged in phased programs to update the safety documentation for the existing US Department of Energy (DOE)-owned facilities. The safety analysis of potential toxic hazards requires a methodology for evaluating human health effects of predicted toxic exposures. This report provides a consistent set of health effects and documents toxicity estimates corresponding to these health effects for some of the more important chemicals found within MMES and MMUS. The estimates are based on published toxicity information and apply to acute exposures for an ``average`` individual. The health effects (toxicological endpoints) used in this report are (1) the detection threshold; (2) the no-observed adverse effect level; (3) the onset of irritation/reversible effects; (4) the onset of irreversible effects; and (5) a lethal exposure, defined to be the 50% lethal level. An irreversible effect is defined as a significant effect on a person`s quality of life, e.g., serious injury. Predicted consequences are evaluated on the basis of concentration and exposure time.

  9. Chemical abundance analysis of the Open Clusters Berkeley 32, NGC 752, Hyades and Praesepe

    CERN Document Server

    Carrera, R

    2011-01-01

    Context. Open clusters are ideal test particles to study the chemical evolution of the Galactic disc. However the existing high-resolution abundance determinations, not only of [Fe/H], but also of other key elements, is largely insufficient at the moment. Aims. To increase the number of Galactic open clusters with high quality abundance determinations, and to gather all the literature determinations published so far. Methods. Using high-resolution (R~30000), high-quality (S/N$>60 per pixel), we obtained spectra for twelve stars in four open clusters with the fiber spectrograph FOCES, at the 2.2 Calar Alto Telescope in Spain. We use the classical equivalent widths analysis to obtain accurate abundances of sixteen elements: Al, Ba, Ca, Co, Cr, Fe, La, Mg, Na, Nd, Ni, Sc, Si, Ti, V, Y. Oxygen abundances have been derived through spectral synthesis of the 6300 A forbidden line. Results. We provide the first determination of abundance ratios other than Fe for NGC 752 giants, and ratios in agreement with the litera...

  10. A differential chemical element analysis of the metal poor Globular Cluster NGC 6397

    CERN Document Server

    Koch, Andreas

    2011-01-01

    We present chemical abundances in three red giants and two turn-off stars in the metal poor Galactic globular cluster (GC) NGC 6397 based on spectroscopy obtained with the MIKE high resolution spectrograph on the Magellan 6.5-m Clay telescope. Our results are based on a line-by-line differential abundance analysis relative to the well-studied red giant Arcturus and the Galactic halo field star Hip 66815. At a mean of -2.10 +/- 0.02 (stat.) +/- 0.07 (sys.) the differential iron abundance is in good agreement with other studies in the literature based on gf-values. As in previous, differential works we find a distinct departure from ionization equilibrium in that the abundances of Fe I and Fe II differ by ~0.1 dex, with opposite sign for the RGB and TO stars. The alpha-element ratios are enhanced to 0.4 (RGB) and 0.3 dex (TO), respectively, and we also confirm strong variations in the O, Na, and Al/Fe abundance ratios. Accordingly, the light-element abundance patterns in one of the red giants can be attributed ...

  11. Chemical and microbiological analysis of public school water in Uberaba Municipality

    Directory of Open Access Journals (Sweden)

    Sérgio Marcos Sanches

    2015-07-01

    Full Text Available This study evaluated the quality of water consumed by schoolchildren in the city of Uberaba, relying upon chemical analyzes to determine the levels of free-residual chlorine and levels of chromium, copper, manganese, lead and cadmium. Microbiological analysis was also performed in order to determine total coliforms and Escherichia coli, using the values established by Ordinance n0 . 2914 of 2011 of the Ministry of Health as parameters for safe drinking water. Water samples were analyzed from the drinking fountains and kitchen faucets of eight public schools that serve children aged 0-5 years. Sampling was conducted quarterly from December 2011 to September 2012, resulting in four collections. The results revealed the presence of Escherichia coli and total coliforms above the valued permitted by legislation in more than 50% of the samples. It was also observed that concentrations of free-residual chlorine were below the minimum value required by law in nearly half of the samples analyzed. In relation to the concentration of metals, some samples had water contents of copper, cadmium, chromium, manganese and lead above the permissible levels. Statistical tests revealed that when analyzing the period of sampling, only the values for the concentrations of free-residual chlorine, chromium and lead showed no significant difference (p> 0.05. The results show the need for corrective actions at the water supply point for the school population, in addition to monitoring and controlling the quality of water for human consumption.

  12. Post-hoc Analysis on the R&D Capabilities of Chemical and Metallurgical Manufacturing

    Directory of Open Access Journals (Sweden)

    Herman Shah Anuar

    2013-09-01

    Full Text Available The purpose of this paper is to evaluate how internal R&D, external R&D, and patenting affects the behavior of foreign, local, and joint-venture companies operating in manufacturing companies in Malaysia. Different types of manufacturing companies may have different approach in applying their R&D capabilities and patenting activity. The construct of this paper is based on the post-hoc analysis in evaluating how internal R&D, external R&D, and patenting affects the behavior of foreign, local, and joint-venture companies operating in manufacturing companies. This research was conducted using survey questionnaires. 124 companies in chemical and metallurgical manufacturing companies participated in this survey. It was indicated that these three companies behave differently when dealing with internal R&D, external R&D, and patenting. It can be concluded that these three types of companies have a different perspective on applying internal R&D, external R&D, and patenting which is based on their different business strategic direction. It is suggested that in the near future, researchers should concentrate and other types of manufacturing companies or they can involve more sample size in getting better generalization on the behavior of these companies.

  13. Physical, chemical and microbiological analysis of the water quality of Rawal Lake, Pakistan

    Directory of Open Access Journals (Sweden)

    Mehreen Hassan

    2014-06-01

    Full Text Available What better gift of nature would be than good quality water? In order to assess the quality of water of Rawal Lake, following research was carried out. Rawal lake is a source of drinking water supplied to many areas of Rawalpindi and Islamabad’ the capital city of Pakistan. Water of this lake is being highly polluted by the local communities alongside the lake through solid waste dumping. Samples of surface water were collected, tested and analyzed in the laboratory on the basis of physical, chemical and microbiological parameters. The results showed uncertainties in many of the selected parameters. Microbiological analysis revealed high contamination of E. coli, fecal coliform and total coliform in the samples proving it unfit for drinking. It was found that the concentration of all physical parameters such as nitrates, chloride, pH and conductivity were within the normal limits. The level of heavy metals like lead, iron, chromium etc. was also found low. Turbidity at some points exceeded the maximum acceptable limit as per WHO statement.

  14. Gaining improved chemical composition by exploitation of Compton-to-Rayleigh intensity ratio in XRF analysis.

    Science.gov (United States)

    Hodoroaba, Vasile-Dan; Rackwitz, Vanessa

    2014-07-15

    The high specificity of the coherent (Rayleigh), as well as incoherent (Compton) X-ray scattering to the mean atomic number of a specimen to be analyzed by X-ray fluorescence (XRF), is exploited to gain more information on the chemical composition. Concretely, the evaluation of the Compton-to-Rayleigh intensity ratio from XRF spectra and its relation to the average atomic number of reference materials via a calibration curve can reveal valuable information on the elemental composition complementary to that obtained from the reference-free XRF analysis. Particularly for matrices of lower mean atomic numbers, the sensitivity of the approach is so high that it can be easily distinguished between specimens of mean atomic numbers differing from each other by 0.1. Hence, the content of light elements which are "invisible" for XRF, particularly hydrogen, or of heavier impurities/additives in light materials can be calculated "by difference" from the scattering calibration curve. The excellent agreement between such an experimental, empirical calibration curve and a synthetically generated one, on the basis of a reliable physical model for the X-ray scattering, is also demonstrated. Thus, the feasibility of the approach for given experimental conditions and particular analytical questions can be tested prior to experiments with reference materials. For the present work a microfocus X-ray source attached on an SEM/EDX (scanning electron microscopy/energy dispersive X-ray spectroscopy) system was used so that the Compton-to-Rayleigh intensity ratio could be acquired with EDX spectral data for improved analysis of the elemental composition. PMID:24950635

  15. Characterization of soil chemical properties of strawberry fields using principal component analysis

    Directory of Open Access Journals (Sweden)

    Gláucia Oliveira Islabão

    2013-02-01

    Full Text Available One of the largest strawberry-producing municipalities of Rio Grande do Sul (RS is Turuçu, in the South of the State. The strawberry production system adopted by farmers is similar to that used in other regions in Brazil and in the world. The main difference is related to the soil management, which can change the soil chemical properties during the strawberry cycle. This study had the objective of assessing the spatial and temporal distribution of soil fertility parameters using principal component analysis (PCA. Soil sampling was based on topography, dividing the field in three thirds: upper, middle and lower. From each of these thirds, five soil samples were randomly collected in the 0-0.20 m layer, to form a composite sample for each third. Four samples were taken during the strawberry cycle and the following properties were determined: soil organic matter (OM, soil total nitrogen (N, available phosphorus (P and potassium (K, exchangeable calcium (Ca and magnesium (Mg, soil pH (pH, cation exchange capacity (CEC at pH 7.0, soil base (V% and soil aluminum saturation(m%. No spatial variation was observed for any of the studied soil fertility parameters in the strawberry fields and temporal variation was only detected for available K. Phosphorus and K contents were always high or very high from the beginning of the strawberry cycle, while pH values ranged from very low to very high. Principal component analysis allowed the clustering of all strawberry fields based on variables related to soil acidity and organic matter content.

  16. Design analysis of 2,000 lb JIB crane for chemical lab

    Energy Technology Data Exchange (ETDEWEB)

    ZIADA, H.H.

    1999-09-22

    A 2,000 lbf jib crane is needed to replace an existing 1,000 lbf jib crane in the Chemical Lab (Building MO-733). The existing 1,000 lbf jib crane (to be replaced) has a 174 boom (I-beam). The crane is attached to the wall through two brackets (about 8 1/2-ft apart). The boom is attached to the lower bracket, and a supporting rod is attached to the upper bracket. The supporting rod is attached to the boom at about 8-ft from the free end. After preliminary studies and discussions, it was decided to construct the new jib crane from two perpendicular I-beams (L-shape) without a supporting rod. The crane is to be supported on the wall through the two lower existing brackets (about 5-ft apart). The boom is to be 20-ft long cantilever (the horizontal I-beam). The vertical I-beam is to be attached to the lower two existing brackets to support the jib crane to the wall. This construction is to be similar to another existing 1,000 lbf jib crane (L-shape) in the lab. The purpose of this document is to perform a design analysis for the proposed 2,000 lbf jib crane to determine suitable sizes of members and configuration of the new jib crane assembly. After construction, if the as-built assembly differs from the 2,000 lbf jib crane as proposed in this document, a revision of this analysis needs to be performed to confirm the acceptability of the as-built assembly.

  17. Chemical analysis of wastewater as a new way of monitoring drugs and medicines consumption at workplace

    Directory of Open Access Journals (Sweden)

    Marek Wiergowski

    2015-12-01

    Full Text Available The available information on the quality and frequency of illegal psychoactive substances used or medicines misused by workers, are often out of date at the time of its publication. This is due to the dynamic introduction of new synthetic drugs on the black market, changes in trends in the recreational use of medicines and the lack of readily available and reliable tests for fast identification. Strategy for detection of narcotic and non-medical psychoactive drugs use at workplace should embrace all possible sources of information. Classical sources of information on the use of psychoactive substances at the workplace include: statistical data (general information on trends and magnitude of drug and medicine addiction collected by the Polish National Police, the National Bureau for Drug Prevention and emergency medical services, surveys, psychomotor tests and qualitative and quantitative analyses of biological material. Of the new and promising methods, used throughout the world in recent years, chemical-toxicological analysis of surface water and wastewater deserve special mention. An increasing interest in the study of urban waste water can significantly complement the source of knowledge about drug and medicine addiction using obtainable conventional methods. In recent years, a municipal wastewater analysis has become a new and very promising way of collecting updated information on the use of psychoactive substances and medicines. It seems that this kind of study may play an important role in the ongoing monitoring of drug and/or medicines use by selected groups of population (e.g., students, military, firemen, policemen, etc.. Med Pr 2015;66(6:837–847

  18. Characterization of a Copper mineral from Rio Grande do Sul (RS, Brazil) by Moessbauer spectroscopy and chemical analysis

    International Nuclear Information System (INIS)

    A sample from a copper-based mineral is analysed by Moessbauer spectroscopy. The results are compared with those form X-ray diffraction and microscopic analyses. A graphic correlation between the areas in the chalcopyrite spectra and the copper contents determined by chemical analysis is also made. (C.L.B.)

  19. Lessons learned from non-medical industries: root cause analysis as culture change at a chemical plant

    OpenAIRE

    Carroll, J; J. Rudolph; Hatakenaka, S

    2002-01-01

    

 Root cause analysis was introduced to a chemical plant as a way of enhancing performance and safety, exemplified by the investigation of an explosion. The cultural legacy of the root cause learning intervention was embodied in managers' increased openness to new ideas, individuals' questioning attitude and disciplined thinking, and a root cause analysis process that provided continual opportunities to learn and improve. Lessons for health care are discussed, taking account of differences b...

  20. Simultaneous Quantitative and Chemical Fingerprint Analysis of Receptaculum Nelumbinis Based on HPLC-DAD-MS Combined with Chemometrics.

    Science.gov (United States)

    Liu, Haitao; Liu, Jiushi; Zhang, Jin; Qi, Yaodong; Jia, Xiaoguang; Zhang, Bengang; Xiao, Peigen

    2016-04-01

    A rapid and sensitive method based on HPLC-DAD-MS was developed for quantitative analysis of two flavonoids and chemical fingerprint analysis to evaluate the quality of Receptaculum Nelumbinis. The analysis was conducted on a Poroshell 120 C18 column (100 × 4.6 mm, 2.7 μm) with 0.2% formic acid buffer solution and methanol as mobile phases with gradient elution. This method displayed good linearity with R(2) at >0.9999 and limits of quantity <0.37 μg mL(-1). Relative standard deviation values for intra- and interday precision were <0.82 and 1.03%, respectively. The mean recovery of hyperoside was 95.54% and of isoquercitrin was 92.10%. Hyperoside and isoquercitrin were determined simultaneously, and 12 peaks in the chemical fingerprint were identified. The chemometric methods, including similarity analysis, hierarchical clustering analysis and principal component analysis, were applied to distinguish 11 batches of Receptaculum Nelumbinis samples. The above results could validate each other and successfully divide these samples into two groups. Moreover, hyperoside and isoquercitrin could be selected as chemical markers to evaluate the quality of Receptaculum Nelumbinis from different localities. This study demonstrated that the developed method was a powerful and beneficial tool to carry out the quality control of Receptaculum Nelumbinis. PMID:26921895

  1. Analysis of chemical profiles of insect adhesion secretions by gas chromatography–mass spectrometry

    Energy Technology Data Exchange (ETDEWEB)

    Reitz, Manuela [Institute of Organic Chemistry, University of Tübingen, Auf der Morgenstelle 8, 72076 Tübingen (Germany); Gerhardt, Heike [Institute of Pharmaceutical Sciences, University of Tübingen, Auf der Morgenstelle 8, 72076 Tübingen (Germany); Schmitt, Christian; Betz, Oliver [Institute of Evolution and Ecology, University of Tübingen, Auf der Morgenstelle 28, 72076 Tübingen (Germany); Albert, Klaus, E-mail: klaus.albert@uni-tuebingen.de [Institute of Organic Chemistry, University of Tübingen, Auf der Morgenstelle 8, 72076 Tübingen (Germany); Lämmerhofer, Michael, E-mail: michael.laemmerhofer@uni-tuebingen.de [Institute of Pharmaceutical Sciences, University of Tübingen, Auf der Morgenstelle 8, 72076 Tübingen (Germany)

    2015-01-07

    Highlights: • Adhesion secretions of desert locust analyzed by GC–MS. • Insect secretions are composed of apolar and polar constituents. • Sampling simplified with contact SPME as compared to solvent sampling. • Thin-film SPME-GC–MS revealed complex alkane patterns for insect secretions. • Differences in tarsal (feet) secretions and samples from tibiae (upper legs) identified. - Abstract: This article reports on the chemical analysis of molecular profiles of tarsal secretions of the desert locust Schistocerca gregaria (Forsskål, 1775) by gas chromatography hyphenated with quadrupol mass spectrometry (GC–MS) as well as {sup 1}H-nuclear magnetic resonance ({sup 1}H NMR) spectroscopy. Special focus of this study was to elaborate on sampling methods which enable selective microscale extraction of insect secretions in a spatially controlled manner, in particular tarsal adhesive secretions and secretions located on cuticle surfaces at the tibia. Various solvent sampling procedures and contact solid-phase microextraction (SPME) methods were compared in terms of comprehensiveness and extraction efficiencies as measured by signal intensities in GC–MS. Solvent sampling with water as extraction solvent gave access to the elucidation of chemical profiles of polar compound classes such as amino acids and carbohydrates, but is extremely tedious. Contact SPME on the other hand can be regarded as a simplified and more elegant alternative, in particular for the lipophilic compound fraction. Many proteinogenic amino acids and ornithine as well as carbohydrate monomers arabinose, xylose, glucose, and galactose were detected in tarsal secretions after acid hydrolysis of aqueous extracts. Qualitatively similar but quantitatively significantly different molecular profiles were found for the lipid fraction which contained mainly n-alkanes and internally branched monomethyl-, dimethyl-, and trimethyl-alkanes in the C23–C49 range as well as long chain fatty acids and

  2. Zinc injection implementation process at EDF: risk analysis, chemical specifications and operating procedures

    International Nuclear Information System (INIS)

    's strategy and the different measures adopted by EDF to provide the necessary tools to the French units : zinc injection procedures, risk analysis, chemistry -radiochemistry surveillance programs, and chemical specifications. This work can be useful for other utilities, assisting them in optimizing and/or implementing the zinc injection in the most suitable conditions, which would help to obtain the expected results in the current and the future reactors. (author)

  3. Chemical composition analysis of simulated waste glass T10-G-16A

    Energy Technology Data Exchange (ETDEWEB)

    Fox, K. M. [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL)

    2015-08-01

    In this report, SRNL provides chemical composition analyses of a simulated LAW glass designated T10-G-16A.The measured chemical composition data are reported and compared with the targeted values for each component. No issues were identified in reviewing the analytical data.

  4. Identification of environmentally relevant chemicals in bibliographic databases: a comparative analysis

    DEFF Research Database (Denmark)

    Ellegaard, Ole; Wallin, Johan Albert

    2013-01-01

    takes as its starting point environmentally important chemicals and the retrieval of selectively chosen substances in the four databases: SciFinder, Web of Science (WoS), Scopus and Google Scholar. The way chemical data are stored in the databases plays a major role in the recovery process...

  5. Identification and Analysis of Student Conceptions Used To Solve Chemical Equilibrium Problems.

    Science.gov (United States)

    Voska, Kirk W.; Heikkinen, Henry W.

    2000-01-01

    Identifies and quantifies the chemistry conceptions used by students when solving chemical equilibrium problems requiring application of LeChatelier's Principle, and explores the feasibility of designing a paper and pencil test to accomplish these purposes. Eleven prevalent incorrect student conceptions about chemical equilibrium were identified…

  6. Introduction to Chemical Engineering Reactor Analysis: A Web-Based Reactor Design Game

    Science.gov (United States)

    Orbey, Nese; Clay, Molly; Russell, T.W. Fraser

    2014-01-01

    An approach to explain chemical engineering through a Web-based interactive game design was developed and used with college freshman and junior/senior high school students. The goal of this approach was to demonstrate how to model a lab-scale experiment, and use the results to design and operate a chemical reactor. The game incorporates both…

  7. Chemical speciation analysis and environmental behaviour of 127I and 12

    International Nuclear Information System (INIS)

    Chemical speciation analysis of 129I and 127I as iodide, iodate and total inorganic iodine in seawater samples from the Baltic Proper, Skagerrak and Kattegat has been carried out. The important findings of this study are that the reduction of iodate and oxidation of iodide in Skagerrak and Kattegat may be a slow process while along the Baltic Sea surface water reduction of iodate is a relatively fast process. Although suboxic or anoxic condition are encountered in some of the Baltic Sea deep basins, the concentration of 129IO3- increases with water depth indicating that the reduction of iodate in the oxygen deficient bottom water of the Baltic Sea is a slow process. Iodine chemical speciation analysis (as iodide, iodate and total iodine including inorganic and organic iodine species) in lake water samples collected from Denmark and southern Sweden has been carried out. Destruction of organic iodine was performed by alkaline oxidation using NaOH - NaClO at 100 deg. C and anion exchange chromatography was used for separation of iodide and iodate. Iodine-129 concentrations in the lakes ranged from 1.3 - 12.8 x109 at/L and show elevated concentrations in lakes located in southwest Jutland (Denmark), near the North Sea. Except the Skaersoe Lake, were the organic iodine - 127 accounts for 50% of the total iodine, iodide (both 129I and 127I) is the predominant species form in surface water of the studied lakes. An investigation was conducted in order to quantify the total aquatic iodine (129I and 127I as inorganic and organic iodine) from fresh water and seawater samples by adsorption onto activated charcoal and DEAE 32 cellulose followed by alkaline digestion or combustion. The results show that iodide from freshwater samples can easily be adsorbed onto activated charcoal. The sorption was not affected by the pH. The absorption capacity of iodate is low and reduces quickly when its concentration increases. Compared with activated charcoal, DEAE 32 cellulose showed a

  8. Practical chemical analysis of Pt and Pd based heterogeneous catalysts with hard X-ray photoelectron spectroscopy

    International Nuclear Information System (INIS)

    Highlights: •Hard X-ray photoelectron spectroscopy (HAXPES) enables interface analysis of catalyst. •HAXPES enables overall analysis of porous film of Pt-doped CeO2 and related catalyst. •HAXPES enables analysis of trace elements for Pd and Pt3Ni nanoparticle catalysts. -- Abstract: Interfacial properties including configuration, porosity, chemical states, and atomic diffusion greatly affect the performance of supported heterogeneous catalysts. Hard X-ray photoelectron spectroscopy (HAXPES) can be used to analyze the interfaces of heterogeneous catalysts because of its large information depth of more than 20 nm. We use HAXPES to examine Pt-doped CeO2 and related thin film catalysts evaporated on Si, carbon, and carbon nanotube substrates, because Pt-doped CeO2 has great potential as a noble metal-based heterogeneous catalyst for fuel cells. The HAXPES measurements clarify that the dopant material, substrate material, and surface pretreatment of substrate are important parameters that affect the interfacial properties of Pt-doped CeO2 and related thin film catalysts. Another advantage of HAXPES measurement of heterogeneous catalysts is that it can be used for chemical analysis of trace elements by detecting photoelectrons from deep core levels, which have large photoionization cross-sections in the hard X-ray region. We use HAXPES for chemical analysis of trace elements in Pd nanoparticle catalysts immobilized on sulfur-terminated substrates and Pt3Ni nanoparticle catalysts enveloped by dendrimer molecules

  9. Chemical analysis of sewage sludge of southern sewerage treatment plant (SSTP) Hyderabad for achieving sustainable development in sector of agriculture

    International Nuclear Information System (INIS)

    A study on the chemical analysis of sewage sludge of southern sewerage treatment plant (SSPP) Hyderabad was studied. Chemical analysis on sludge samples collected form the waste stabilization for different micro-nutrients (essential manures, nitrogen, phosphorus, potassium, calcium and magnesium) were conducted in year 1999-2000. These nutrients and metal were detected by reliable analytical method i.e. Kjeldahls method and Atomic Absorption Spectrophotometer. The analysis showed that sewage sludge contained sufficient quantity of primary and secondary nutrients, hence sewage sludge could be utilized as a natural fertilizer. This will not only solve the disposal problem but it would also be environmentally safer way of providing regulators to the plants. (author)

  10. Energy Analysis of Aluminosilicate Zeolites with Comprehensive Ranges of Framework Topologies, Chemical Compositions, and Aluminum Distributions.

    Science.gov (United States)

    Muraoka, Koki; Chaikittisilp, Watcharop; Okubo, Tatsuya

    2016-05-18

    The contents and locations of Al in the zeolite frameworks are one of the key factors determining the physicochemical properties of zeolites. Systematic evaluation of the characteristics of zeolites with a wide variety of framework topologies, a wide range of Si/Al ratios, and various locations of Al is of great significance, but very challenging due to the limitation of the realizable ranges of Al contents in zeolites as well as the limited information on the Al locations obtained from the current analytical techniques. Here, we report the systematic analysis of the energetics of aluminosilicate zeolites with 209 existing framework topologies at different Si/Al ratios using molecular mechanics. More than 43 000 initial structures were generated to give comprehensive views of the energetics of zeolites. The results coincide well with the structural knowledge obtained experimentally. It was revealed that the relation between the relative framework energies versus the Al contents varies in accordance with the topologies, suggesting that the relative stability of zeolites depends not only on the topologies, but also on the substituting contents of Al. For particular topologies with the same Al contents, in addition, comparisons between random and specific distributions of Al showed that zeolite with Al at a particular T site is energetically more stable than those with random distributions, suggesting the inherent influences of the Al locations. The contents and locations of Al in zeolites likely have a certain preference that may reflect the range of chemical compositions, the Al distributions, and consequently the physicochemical properties of realizable aluminosilicate zeolites. PMID:27097121

  11. Abundance analysis of an extended sample of open clusters: A search for chemical inhomogeneities

    Science.gov (United States)

    Reddy, Arumalla B. S.; Giridhar, Sunetra; Lambert, David L.

    We have initiated a program to explore the presence of chemical inhomogeneities in the Galactic disk using the open clusters as ideal probes. We have analyzed high-dispersion echelle spectra (R ≥ 55,000) of red giant members for eleven open clusters to derive abundances for many elements. The membership to the cluster has been confirmed through their radial velocities and proper motions. The spread in temperatures and gravities being very small among the red giants, nearly the same stellar lines were employed thereby reducing the random errors. The errors of average abundance for the cluster were generally in 0.02 to 0.07 dex range. Our present sample covers galactocentric distances of 8.3 to 11.3 kpc and an age range of 0.2 to 4.3 Gyrs. Our earlier analysis of four open clusters (Reddy A.B.S. et al., 2012, MNRAS, 419,1350) indicate that abundances relative to Fe for elements from Na to Eu are equal within measurement uncertainties to published abundances for thin disk giants in the field. This supports the view that field stars come from disrupted open clusters. In the enlarged sample of eleven open clusters we find cluster to cluster abundance variations for some s- and r- process elements, with certain elements such as Zr and Ba showing large variation. These differences mark the signatures that these clusters had formed under different environmental conditions (Type II SN, Type Ia SN, AGB stars or a mixture of any of these) unique to the time and site of formation. These eleven clusters support the widely held impression that there is an abundance gradient such that the metallicity [Fe/H] at the solar galactocentric distance decreases outwards at about -0.1 dex per kpc.

  12. Mass, energy, and exergy balance analysis of chemical looping with oxygen uncoupling (CLOU) process

    International Nuclear Information System (INIS)

    Highlights: • A CLOU reactor system using a CuO-based OC and coal as fuel is analyzed. • Possible operational regions for the chosen OC are identified. • Different heat balance scenarios are investigated. • The second-law efficiency of the system is evaluated. • Various design aspects and process modelling relationships are discussed. - Abstract: Chemical looping with oxygen uncoupling (CLOU) is a promising concept for efficient combustion of solid fuels with an inherent capture of the greenhouse gas CO2. This paper presents a CLOU process scheme with stoichiometric mass, energy, and exergy balances. A CLOU reactor system using medium volatile bituminous coal as fuel and silica-supported CuO as an oxygen carrier is analyzed. The analysis includes the estimation of various design and operational parameters, thermal considerations, and evaluation of the overall performance. The operation of a reactor system of two interacting circulating fluidized beds (CFBs) is greatly influenced by the hydrodynamics. For the CuO oxygen carrier, the hydrodynamic operating range appeared feasible considering the maximum solid circulation rates in current CFB boilers. Depending upon the reactor temperatures, oxygen carrier inventories of 400–680 kg/MW in the system were found necessary for stoichiometric combustion of the fuel. The temperature difference between the reactors should not exceed 50 °C, as otherwise, problems may arise with the heat balance. Exergetic efficiencies in the range of 63–70% were obtained for different combinations of relevant design parameters. It is evident that the possible operating conditions in the system are closely related to the properties of the chosen oxygen carrier. However, the calculation procedure and design criteria presented here are applicable to any oxygen carrier to be used in the process

  13. Particle Generation by Laser Ablation in Support of Chemical Analysis of High Level Mixed Waste from Plutonium Production Operations

    International Nuclear Information System (INIS)

    Investigate particles produced by laser irradiation and their analysis by Laser Ablation Inductively Coupled Plasma Mass Spectroscopy (LA/ICP-MS), with a view towards optimizing particle production for analysis of high level waste materials and waste glass. LA/ICP-MS has considerable potential to increase the safety and speed of analysis required for the remediation of high level wastes from cold war plutonium production operations. In some sample types, notably the sodium nitrate-based wastes at Hanford and elsewhere, chemical analysis using typical laser conditions depends strongly on the details of sample history composition in a complex fashion, rendering the results of analysis uncertain. Conversely, waste glass materials appear to be better behaved and require different strategies to optimize analysis

  14. Analysis of chemical warfare agents in organic liquid samples with magnetic dispersive solid phase extraction and gas chromatography mass spectrometry for verification of the chemical weapons convention.

    Science.gov (United States)

    Singh, Varoon; Purohit, Ajay Kumar; Chinthakindi, Sridhar; Goud, Raghavender D; Tak, Vijay; Pardasani, Deepak; Shrivastava, Anchal Roy; Dubey, Devendra Kumar

    2016-05-27

    A simple, sensitive and low temperature sample preparation method is developed for detection and identification of Chemical Warfare Agents (CWAs) and scheduled esters in organic liquid using magnetic dispersive solid phase extraction (MDSPE) followed by gas chromatography-mass spectrometry analysis. The method utilizes Iron oxide@Poly(methacrylic acid-co-ethylene glycol dimethacrylate) resin (Fe2O3@Poly(MAA-co-EGDMA)) as sorbent. Variants of these sorbents were prepared by precipitation polymerization of methacrylic acid-co-ethylene glycol dimethacrylate (MAA-co-EGDMA) onto Fe2O3 nanoparticles. Fe2O3@poly(MAA-co-EGDMA) with 20% MAA showed highest recovery of analytes. Extractions were performed with magnetic microspheres by MDSPE. Parameters affecting the extraction efficiency were studied and optimized. Under the optimized conditions, method showed linearity in the range of 0.1-3.0μgmL(-1) (r(2)=0.9966-0.9987). The repeatability and reproducibility (relative standard deviations (RSDs) %) were in the range of 4.5-7.6% and 3.4-6.2% respectively for organophosphorous esters in dodecane. Limits of detection (S/N=3/1) and limit of quantification (S/N=10/1) were found to be in the range of 0.05-0.1μgmL(-1) and 0.1-0.12μgmL(-1) respectively in SIM mode for selected analytes. The method was successfully validated and applied to the extraction and identification of targeted analytes from three different organic liquids i.e. n-hexane, dodecane and silicon oil. Recoveries ranged from 58.7 to 97.3% and 53.8 to 95.5% at 3μgmL(-1) and 1μgmL(-1) spiking concentrations. Detection of diethyl methylphosphonate (DEMP) and O-Ethyl S-2-diisopropylaminoethyl methylphosphonothiolate (VX) in samples provided by the Organization for Prohibition of Chemical Weapons Proficiency Test (OPCW-PT) proved the utility of the developed method for the off-site analysis of CWC relevant chemicals. PMID:27113675

  15. Thermodynamic analysis of chemical compatibility of several compounds with Fe-Cr-Al alloys

    Science.gov (United States)

    Misra, Ajay K.

    1993-01-01

    Chemical compatibility between Fe-19.8Cr-4.8Al (weight percent), which is the base composition for the commercial superalloy MA956, and several carbides, borides, nitrides, oxides, and silicides was analyzed from thermodynamic considerations. The effect of addition of minor alloying elements, such as Ti, Y, and Y2O3, to the Fe-Cr-Al alloy on chemical compatibility between the alloy and various compounds was also analyzed. Several chemically compatible compounds that can be potential reinforcement materials and/or interface coating materials for Fe-Cr-Al based composites were identified.

  16. Thermodynamic analysis of chemical compatibility of several reinforcement materials with niobium aluminides. Final contractor report

    International Nuclear Information System (INIS)

    Chemical compatibility of several reinforcement materials with three niobium aluminides, Nb3Al, Nb2Al, and NbAl3, were examined from thermodynamic considerations. The reinforcement materials considered in this study include carbides, borides, nitrides, oxides, silicides, and Engel-Brewer compounds. Thermodynamics of the Nb-Al system were reviewed and activities of Nb and Al were derived at desired calculation temperatures. Criteria for chemical compatibility between the reinforcement material and Nb-Al compounds have been defined and several chemically compatible reinforcement materials have been identified

  17. Thermodynamic analysis of chemical compatibility of ceramic reinforcement materials with niobium aluminides

    Science.gov (United States)

    Misra, Ajay K.

    1990-01-01

    Chemical compatibility of several reinforcement materials with three niobium aluminides, Nb3Al, Nb2Al, and NbAl3, were examined from thermodynamic considerations. The reinforcement materials considered in this study include carbides, borides, nitrides, oxides, silicides, and Engel-Brewer compounds. Thermodynamics of the Nb-Al system were reviewed and activities of Nb and Al were derived at desired calculation temperatures. Criteria for chemical compatibility between the reinforcement material and Nb-Al compounds have been defined and several chemically compatible reinforcement materials have been identified.

  18. Thermodynamic analysis of chemical compatibility of several reinforcement materials with niobium aluminides

    Science.gov (United States)

    Misra, Ajay K.

    1989-01-01

    Chemical compatibility of several reinforcement materials with three niobium aluminides, Nb3Al, Nb2Al, and NbAl3, were examined from thermodynamic considerations. The reinforcement materials considered in this study include carbides, borides, nitrides, oxides, silicides, and Engel-Brewer compounds. Thermodynamics of the Nb-Al system were reviewed and activities of Nb and Al were derived at desired calculation temperatures. Criteria for chemical compatibility between the reinforcement material and Nb-Al compounds have been defined and several chemically compatible reinforcement materials have been identified.

  19. Nano-structural and Nano-chemical analysis of dissimilar metal weld interfaces

    Energy Technology Data Exchange (ETDEWEB)

    Choi, Kyoung Joon; Shin, Sang Hoon; Kim, Jong Jin; Jung, Ju Ang; Kim, Ji Hyun [Ulsan National Institute of Science and Technology, Ulsan (Korea, Republic of)

    2012-05-15

    Dissimilar Metal Welds (DMWs) is generally applied to nuclear power plants for manufacturing and machining in structural components such as reactor pressure vessels and pressurizer nozzles. Alloy 152 is used frequently as filler metal in the manufacture of the DMW in light water reactors to join the low alloy steel pressure vessel nozzles and steam generator nozzles to nickel-based wrought alloy or austenitic stainless steel components. However, in recent years cracking phenomena has been observed in the welded joints. Concerns have been raised to the integrity and reliability in the joint transition zone due to the high susceptibility of the heat affected zone (HAZ) and the fusion boundary (FB) to stress corrosion cracking in combination with thermal aging. Since the material microstructure and chemical composition are key parameters affecting the stress corrosion cracking, improving the understanding of stress corrosion cracking at the FB region requires fundamental understanding of the unique microstructure of the FB region in DMW. Despite the potential degradation and consequent risk in the DMW, there is still a lack of the fundamental understanding of microstructure in the FB region, in particular the region containing unidentified band structures near the FB. The scale of the microstructure in modern metallic materials is becoming increasingly smaller. The 3-dimensional atom probe tomography (3D APT) has a truly quantitative analytical capability to characterize nanometer scale particles in metallic materials, thus its application to the microstructural analysis in multi-component metallic materials provides critical information on the mechanism of nanoscale microstructural evolution. The 3D APT is a microscope that allows the reconstruction of 3D 'atom maps'. These reconstructions can be interrogated and interpreted to determine the nanoscale chemistry of the material. Therefore, the current study is aiming at the establishment of detail procedure

  20. Analysis of Physical, Chemical and Microbiological Pollution in one Right Click

    International Nuclear Information System (INIS)

    Current researches on the topic of indoor air pollution are moving towards expertise and prevention. Therefore it seems so critical to invest in the area of expertise and create a measuring device performing chemical, physical and bacteriological analysis in one click. Our choice of development towards this system of information management is oriented towards a modular system which can simultaneously transmit on real-time the analysis in the internet. Our production work has used several solutions and analyzed several possible methods such as microprocessor that has shown its reliability. The electronic system worked well even with some problems solved at the level of detection of particles α, β and γ. The solution NO-IP as for the transfer of data over the Internet has been successfully tested. In the same way we have been constrained to achieve measurement campaigns to verify the ability of the device to give consistent values. These campaigns were conducted on the Beaulieu of the University of Rennes 1, given the size of the site; it gives us a fairly comprehensive range of situations. These measurement campaigns extended for several months, with the purpose of comparing and analyzing the various results. These campaigns offer an opportunity of testing the operation of the aircraft and assessing the performance, knowing that all measures were compared to the device certified EN (Gasman). For the development of our device, we specify the direction and scope of the study area, analyze the existing level of detection performed and technical data manipulated, obtain a comprehensive description of the electronic system and reach a reasoned choice of a solution type of development. This allowed us to develop a multifunction prototype which objective is to control the quality of indoor air pollution in habitations. This device admits the same principle as product modem M2M (Machine to Machine). Through processes M2M, machinery (measuring instruments (device) and air

  1. CRITIC2: A program for real-space analysis of quantum chemical interactions in solids

    Science.gov (United States)

    Otero-de-la-Roza, A.; Johnson, Erin R.; Luaña, Víctor

    2014-03-01

    We present CRITIC2, a program for the analysis of quantum-mechanical atomic and molecular interactions in periodic solids. This code, a greatly improved version of the previous CRITIC program (Otero-de-la Roza et al., 2009), can: (i) find critical points of the electron density and related scalar fields such as the electron localization function (ELF), Laplacian, … (ii) integrate atomic properties in the framework of Bader’s Atoms-in-Molecules theory (QTAIM), (iii) visualize non-covalent interactions in crystals using the non-covalent interactions (NCI) index, (iv) generate relevant graphical representations including lines, planes, gradient paths, contour plots, atomic basins, … and (v) perform transformations between file formats describing scalar fields and crystal structures. CRITIC2 can interface with the output produced by a variety of electronic structure programs including WIEN2k, elk, PI, abinit, Quantum ESPRESSO, VASP, Gaussian, and, in general, any other code capable of writing the scalar field under study to a three-dimensional grid. CRITIC2 is parallelized, completely documented (including illustrative test cases) and publicly available under the GNU General Public License. Catalogue identifier: AECB_v2_0 Program summary URL:http://cpc.cs.qub.ac.uk/summaries/AECB_v2_0.html Program obtainable from: CPC Program Library, Queen’s University, Belfast, N. Ireland Licensing provisions: yes No. of lines in distributed program, including test data, etc.: 11686949 No. of bytes in distributed program, including test data, etc.: 337020731 Distribution format: tar.gz Programming language: Fortran 77 and 90. Computer: Workstations. Operating system: Unix, GNU/Linux. Has the code been vectorized or parallelized?: Shared-memory parallelization can be used for most tasks. Classification: 7.3. Catalogue identifier of previous version: AECB_v1_0 Journal reference of previous version: Comput. Phys. Comm. 180 (2009) 157 Nature of problem: Analysis of quantum-chemical

  2. Sampling and analysis of chemical element concentration distribution in rock units and orebodies

    Directory of Open Access Journals (Sweden)

    F. P. Agterberg

    2012-01-01

    Full Text Available Existing sampling techniques applied within known orebodies, such as sampling along mining drifts, yield element concentration values for larger blocks of ore if they are extended into their surroundings. The resulting average concentration values have relatively small "extension variance". These techniques can be used for multifractal modeling as well as ore reserve estimation approaches. Geometric probability theory can aid in local spatial covariance modeling. It provides information about increase of variability of element concentration over short distances exceeding microscopic scale. In general, the local clustering of ore crystals results in small-scale variability known as the "nugget effect". Parameters to characterize spatial covariance estimated from ore samples subjected to chemical analysis for ore reserve estimation may not be valid at local scale because of the nugget effect. The novel method of local singularity mapping applied within orebodies provides new insights into the nature of the nugget effect. Within the Pulacayo orebody, Bolivia, local singularity for zinc is linearly related with logarithmically transformed concentration value. If there is a nugget effect, moving averages resulting from covariance models or estimated by other methods that have a smoothing effect, such as kriging, can be improved by incorporating local singularities indicating local element enrichment or depletion. Although there have been many successful applications of the multifractal binomial/p model, its application within the Pulacayo orebody results in inconsistencies, indicating some shortcomings of this relatively simple approach. Local singularity analysis and universal multifractal modeling are two promising new approaches to improve upon results obtained by commonly used geostatistical techniques and use of the binomial/p model. All methods in this paper are illustrated using a single example (118 Pulacayo zinc values, and

  3. Surface reactivity and layer analysis of chemisorbed reaction films in the surface-chemical environment of alkyl octadecenoates

    Indian Academy of Sciences (India)

    R B Choudhary; O N Anand; O S Tyagi

    2009-05-01

    Studies on surface reactivity of substrate iron (Fe-particles) were made in the tribo-chemical environment of alkyl octadecenoates. Two alkyl octadecenoates namely ethyl octadecenoate and methyl 12-hydroxy octadecenoate, slightly different in their chemical nature, were taken for preparing the chemisorbed reaction films (CRF) at the temperature 100 ± 5°C. The reaction products collected in the composite (amorphous) phase were isolated into three different solvent-soluble fractions (sub-layer films) using polar solvents of increasing polar strength. The FTIR analysis of these films showed that these were primarily organic in nature and were composed of alkyl and/or aryl hydroxy ethers, unsaturated hydroxy ketones, and aromatic structures chemically linked with iron surface. These reaction films also contained large amount of iron (Fe). Further, these film fractions also showed varying thermal behaviour during thermal decomposition in the temperature range of 50-800°C when thermally evaluated in the nitrogen environment.

  4. Chemical profiling and classification of illicit heroin by principal component analysis, calculation of inter sample correlation and artificial neural networks.

    Science.gov (United States)

    Esseiva, Pierre; Anglada, Frederic; Dujourdy, Laurence; Taroni, Franco; Margot, Pierre; Pasquier, Eric Du; Dawson, Michael; Roux, Claude; Doble, Philip

    2005-08-15

    Artificial neural networks (ANNs) were utilised to validate illicit drug classification in the profiling method used at "Institut de Police Scientifique" of the University of Lausanne (IPS). This method established links between samples using a combination of principal component analysis (PCA) and calculation of a correlation value between samples. Heroin seizures sent to the IPS laboratory were analysed using gas chromatography (GC) to separate the major alkaloids present in illicit heroin. Statistical analysis was then performed on 3371 samples. Initially, PCA was performed as a preliminary screen to identify samples of a similar chemical profile. A correlation value was then calculated for each sample previously identified with PCA. This correlation value was used to determine links between drug samples. These links were then recorded in an Ibase((R)) database. From this database the notion of "chemical class" arises, where samples with similar chemical profiles are grouped together. Currently, about 20 "chemical classes" have been identified. The normalised peak areas of six target compounds were then used to train an ANN to classify each sample into its appropriate class. Four hundred and sixty-eight samples were used as a training data set. Sixty samples were treated as blinds and 370 as non-linked samples. The results show that in 96% of cases the neural network attributed the seizure to the right "chemical class". The application of a neural network was found to be a useful tool to validate the classification of new drug seizures in existing chemical classes. This tool should be increasingly used in such situations involving profile comparisons and classifications.

  5. Chemical analysis of Mycenaean pottery from the Menelaion and its vicinity

    OpenAIRE

    Jones, R E; Tomlinson, J.T.

    2009-01-01

    A chemical characterisation of the Mycenaean pottery from the major prehistoric site of the Menelaion in Laconia. The study defines the the lcoal pottery production and identifies the imports from various centres.

  6. Predicting the redox state and secondary structure of cysteine residues using multi-dimensional classification analysis of NMR chemical shifts.

    Science.gov (United States)

    Wang, Ching-Cheng; Lai, Wen-Chung; Chuang, Woei-Jer

    2016-09-01

    A tool for predicting the redox state and secondary structure of cysteine residues using multi-dimensional analyses of different combinations of nuclear magnetic resonance (NMR) chemical shifts has been developed. A data set of cysteine [Formula: see text], (13)C(α), (13)C(β), (1)H(α), (1)H(N), and (15)N(H) chemical shifts was created, classified according to redox state and secondary structure, using a library of 540 re-referenced BioMagResBank (BMRB) entries. Multi-dimensional analyses of three, four, five, and six chemical shifts were used to derive rules for predicting the structural states of cysteine residues. The results from 60 BMRB entries containing 122 cysteines showed that four-dimensional analysis of the C(α), C(β), H(α), and N(H) chemical shifts had the highest prediction accuracy of 100 and 95.9 % for the redox state and secondary structure, respectively. The prediction of secondary structure using 3D, 5D, and 6D analyses had the accuracy of ~90 %, suggesting that H(N) and [Formula: see text] chemical shifts may be noisy and made the discrimination worse. A web server (6DCSi) was established to enable users to submit NMR chemical shifts, either in BMRB or key-in formats, for prediction. 6DCSi displays predictions using sets of 3, 4, 5, and 6 chemical shifts, which shows their consistency and allows users to draw their own conclusions. This web-based tool can be used to rapidly obtain structural information regarding cysteine residues directly from experimental NMR data.

  7. Analysis of Environmental Chemical Mixtures and Non-Hodgkin Lymphoma Risk in the NCI-SEER NHL Study

    Science.gov (United States)

    Czarnota, Jenna; Gennings, Chris; Colt, Joanne S.; De Roos, Anneclaire J.; Cerhan, James R.; Severson, Richard K.; Hartge, Patricia; Ward, Mary H.

    2015-01-01

    , Wheeler DC. 2015. Analysis of environmental chemical mixtures and non-Hodgkin lymphoma risk in the NCI-SEER NHL Study. Environ Health Perspect 123:965–970; http://dx.doi.org/10.1289/ehp.1408630 PMID:25748701

  8. Physico Chemical Analysis of Municipal Wastewater Discharge in Ganga River,Haridwar District of Uttarakhand, India

    OpenAIRE

    Saba Shirin; Akhilesh Kumar Yadav

    2014-01-01

    This study was aimed to screen the water quality of Ganga River in Haridwar city, Uttarakhand, India. The study was conducted based on their water source, origin of pollution such as utilisation by human and animals. Monthly changes in physico-chemical parameters such as pH, Temperature, Total Dissolved Solids, Total Solids, Total Suspended Solids, Chemical Oxygen Demand, Dissolved oxygen, Biochemical Oxygen Demand and Volatile Suspended Solids were analyzed for a period of twoyear fromJanuar...

  9. Multivariate analysis of chemical properties in oxisols with different levels of intervention agricultural

    OpenAIRE

    Camacho-Tamayo, Jesús H.; Luengas-Gómez, Carlos; Fabio R Leiva

    2010-01-01

    Human intervention in agricultural production affects directly soil quality by promoting changes in physical and chemical properties through the use of fertilizers, correctives and tillage practices (Brachiria and corn- soybean). The aim of this study was to evaluate changes in the chemical properties of two Oxisols (Typic Hapludox y Typic Haplustox) with different intervention levels, in the municipality of Puerto Lopez (Meta-Colombia). Samples were taken at 42 points, spaced 25 m perpendicu...

  10. Analysis and Physico-Chemical Parameters of Sarvar Devla Sugar Mill Studies of Effluents

    Directory of Open Access Journals (Sweden)

    R. K. Pathak

    2012-12-01

    Full Text Available The physico-chemical characteristics contents in the effluents discharged from Neoly sugar mill have been explored. The physico-chemical parameters such as colour, odour, temperature, pH, electrical conductivity, COD, BOD, alkalinity, total hardness,Ca+2, Mg+2, chloride, of the effluent collected from the various sites between the exit point at the mill and discharge point In, have been determined.

  11. Preliminary analysis of chemical reaction under the radiation of electromagnetic wave

    Institute of Scientific and Technical Information of China (English)

    2000-01-01

    Microwave can be used to accelerate chemical reaction and improve the rate of production.Does microwave only act as a heating factor? Do there exist any specific effects? These questions are still holding a violent controversy.Here we will choose the Belousov- Zhabotinsky reaction,which is sensitive to surrounding effects,to study the influence of microwave on chemical reactions.Visible changes of periods have been observed.It appeares that there could have been specific effects of microwave.

  12. Analysis of primary coolant pump seal water distribution influence to chemical and volume system design

    International Nuclear Information System (INIS)

    The possible influences to Chemical and Volume Control System design caused by coolant pump seal water distribution are discussed. The essential reason is picked out in this paper. The temperature drop of charging flow at the regenerative heat exchanger outlet is calculated, and the feasible retrofits of the Chemical and Volume Control System are illustrated. The thermal hydraulic software Flowmaster 7.5 is employed to numerically investigate the possible capability of charging pump with different coolant pump seal requirements. (authors)

  13. Chemical Analysis of Whale Breath Volatiles: A Case Study for Non-Invasive Field Health Diagnostics of Marine Mammals

    Directory of Open Access Journals (Sweden)

    Raquel Cumeras

    2014-09-01

    Full Text Available We explored the feasibility of collecting exhaled breath from a moribund gray whale (Eschrichtius robustus for potential non-invasive health monitoring of marine mammals. Biogenic volatile organic compound (VOC profiling is a relatively new field of research, in which the chemical composition of breath is used to non-invasively assess the health and physiological processes on-going within an animal or human. In this study, two telescopic sampling poles were designed and tested with the primary aim of collecting whale breath exhalations (WBEs. Once the WBEs were successfully collected, they were immediately transferred onto a stable matrix sorbent through a custom manifold system. A total of two large volume WBEs were successfully captured and pre-concentrated onto two Tenax®-TA traps (one exhalation per trap. The samples were then returned to the laboratory where they were analyzed using solid phase micro extraction (SPME and gas chromatography/mass spectrometry (GC/MS. A total of 70 chemicals were identified (58 positively identified in the whale breath samples. These chemicals were also matched against a database of VOCs found in humans, and 44% of chemicals found in the whale breath are also released by healthy humans. The exhaled gray whale breath showed a rich diversity of chemicals, indicating the analysis of whale breath exhalations is a promising new field of research.

  14. Biological Sampling and Analysis in Sinclair and Dyes Inlets, Washington: Chemical Analyses for 2007 Puget Sound Biota Study

    Energy Technology Data Exchange (ETDEWEB)

    Brandenberger, Jill M.; Suslick, Carolynn R.; Johnston, Robert K.

    2008-10-09

    Evaluating spatial and temporal trends in contaminant residues in Puget Sound fish and macroinvertebrates are the objectives of the Puget Sound Ambient Monitoring Program (PSAMP). In a cooperative effort between the ENVironmental inVESTment group (ENVVEST) and Washington State Department of Fish and Wildlife, additional biota samples were collected during the 2007 PSAMP biota survey and analyzed for chemical residues and stable isotopes of carbon (δ13C) and nitrogen (δ15N). Approximately three specimens of each species collected from Sinclair Inlet, Georgia Basin, and reference locations in Puget Sound were selected for whole body chemical analysis. The muscle tissue of specimens selected for chemical analyses were also analyzed for δ13C and δ15N to provide information on relative trophic level and food sources. This data report summarizes the chemical residues for the 2007 PSAMP fish and macro-invertebrate samples. In addition, six Spiny Dogfish (Squalus acanthias) samples were necropsied to evaluate chemical residue of various parts of the fish (digestive tract, liver, embryo, muscle tissue), as well as, a weight proportional whole body composite (WBWC). Whole organisms were homogenized and analyzed for silver, arsenic, cadmium, chromium, copper, nickel, lead, zinc, mercury, 19 polychlorinated biphenyl (PCB) congeners, PCB homologues, percent moisture, percent lipids, δ13C, and δ15N.

  15. Analysis of the comprehensibility of chemical hazard communication tools at the industrial workplace.

    Science.gov (United States)

    Ta, Goh Choo; Mokhtar, Mazlin Bin; Mohd Mokhtar, Hj Anuar Bin; Ismail, Azmir Bin; Abu Yazid, Mohd Fadhil Bin Hj

    2010-01-01

    Chemical classification and labelling systems may be roughly similar from one country to another but there are significant differences too. In order to harmonize various chemical classification systems and ultimately provide consistent chemical hazard communication tools worldwide, the Globally Harmonized System of Classification and Labelling of Chemicals (GHS) was endorsed by the United Nations Economic and Social Council (ECOSOC). Several countries, including Japan, Taiwan, Korea and Malaysia, are now in the process of implementing GHS. It is essential to ascertain the comprehensibility of chemical hazard communication tools that are described in the GHS documents, namely the chemical labels and Safety Data Sheets (SDS). Comprehensibility Testing (CT) was carried out with a mixed group of industrial workers in Malaysia (n=150) and factors that influence the comprehensibility were analysed using one-way ANOVA. The ability of the respondents to retrieve information from the SDS was also tested in this study. The findings show that almost all the GHS pictograms meet the ISO comprehension criteria and it is concluded that the underlying core elements that enhance comprehension of GHS pictograms and which are also essential in developing competent persons in the use of SDS are training and education. PMID:20616463

  16. LSENS, a general chemical kinetics and sensitivity analysis code for homogeneous gas-phase reactions. 2: Code description and usage

    Science.gov (United States)

    Radhakrishnan, Krishnan; Bittker, David A.

    1994-01-01

    LSENS, the Lewis General Chemical Kinetics Analysis Code, has been developed for solving complex, homogeneous, gas-phase chemical kinetics problems and contains sensitivity analysis for a variety of problems, including nonisothermal situations. This report is part 2 of a series of three reference publications that describe LSENS, provide a detailed guide to its usage, and present many example problems. Part 2 describes the code, how to modify it, and its usage, including preparation of the problem data file required to execute LSENS. Code usage is illustrated by several example problems, which further explain preparation of the problem data file and show how to obtain desired accuracy in the computed results. LSENS is a flexible, convenient, accurate, and efficient solver for chemical reaction problems such as static system; steady, one-dimensional, inviscid flow; reaction behind incident shock wave, including boundary layer correction; and perfectly stirred (highly backmixed) reactor. In addition, the chemical equilibrium state can be computed for the following assigned states: temperature and pressure, enthalpy and pressure, temperature and volume, and internal energy and volume. For static problems the code computes the sensitivity coefficients of the dependent variables and their temporal derivatives with respect to the initial values of the dependent variables and/or the three rate coefficient parameters of the chemical reactions. Part 1 (NASA RP-1328) derives the governing equations describes the numerical solution procedures for the types of problems that can be solved by lSENS. Part 3 (NASA RP-1330) explains the kinetics and kinetics-plus-sensitivity-analysis problems supplied with LSENS and presents sample results.

  17. Plant seed species identification from chemical fingerprints: a high-throughput application of direct analysis in real time mass spectrometry.

    Science.gov (United States)

    Lesiak, Ashton D; Cody, Robert B; Dane, A John; Musah, Rabi A

    2015-09-01

    Plant species identification based on the morphological features of plant parts is a well-established science in botany. However, species identification from seeds has largely been unexplored, despite the fact that the seeds contain all of the genetic information that distinguishes one plant from another. Using seeds of genus Datura plants, we show here that the mass spectrum-derived chemical fingerprints for seeds of the same species are similar. On the other hand, seeds from different species within the same genus display distinct chemical signatures, even though they may contain similar characteristic biomarkers. The intraspecies chemical signature similarities on the one hand, and interspecies fingerprint differences on the other, can be processed by multivariate statistical analysis methods to enable rapid species-level identification and differentiation. The chemical fingerprints can be acquired rapidly and in a high-throughput manner by direct analysis in real time mass spectrometry (DART-MS) analysis of the seeds in their native form, without use of a solvent extract. Importantly, knowledge of the identity of the detected molecules is not required for species level identification. However, confirmation of the presence within the seeds of various characteristic tropane and other alkaloids, including atropine, scopolamine, scopoline, tropine, tropinone, and tyramine, was accomplished by comparison of the in-source collision-induced dissociation (CID) fragmentation patterns of authentic standards, to the fragmentation patterns observed in the seeds when analyzed under similar in-source CID conditions. The advantages, applications, and implications of the chemometric processing of DART-MS derived seed chemical signatures for species level identification and differentiation are discussed.

  18. Analysis of a Stochastic Chemical System Close to a SNIPER Bifurcation of Its Mean-Field Model

    KAUST Repository

    Erban, Radek

    2009-01-01

    A framework for the analysis of stochastic models of chemical systems for which the deterministic mean-field description is undergoing a saddle-node infinite period (SNIPER) bifurcation is presented. Such a bifurcation occurs, for example, in the modeling of cell-cycle regulation. It is shown that the stochastic system possesses oscillatory solutions even for parameter values for which the mean-field model does not oscillate. The dependence of the mean period of these oscillations on the parameters of the model (kinetic rate constants) and the size of the system (number of molecules present) are studied. Our approach is based on the chemical Fokker-Planck equation. To gain some insight into the advantages and disadvantages of the method, a simple one-dimensional chemical switch is first analyzed, and then the chemical SNIPER problem is studied in detail. First, results obtained by solving the Fokker-Planck equation numerically are presented. Then an asymptotic analysis of the Fokker-Planck equation is used to derive explicit formulae for the period of oscillation as a function of the rate constants and as a function of the system size. © 2009 Society for Industrial and Applied Mathematics.

  19. Chemical or Biological Terrorist Attacks: An Analysis of the Preparedness of Hospitals for Managing Victims Affected by Chemical or Biological Weapons of Mass Destruction

    Directory of Open Access Journals (Sweden)

    Russell L. Bennett

    2006-03-01

    and analysis. Six hypotheses were tested. Using a questionnaire survey, the availability of functional preparedness plans, specific preparedness education/training, decontamination facilities, surge capacity, pharmaceutical supplies, and laboratory diagnostic capabilities of hospitals were examined. The findings revealed that a majority (89.2% of hospitals in the State of Mississippi have documented preparedness plans, provided specific preparedness education/training (89.2%, have dedicated facilities for decontamination (75.7%, and pharmaceutical plans and supplies (56.8% for the treatment of victims in the event of a disaster involving chemical or biological WMD. However, over half (59.5% of the hospitals could not increase surge capacity (supplies, equipment, staff, patient beds, etc. and lack appropriate laboratory diagnostic services (91.9% capable of analyzing and identifying WMD. In general, hospitals in the State of Mississippi, like a number of hospitals throughout the United States, are still not adequately prepared to manage victims of terrorist attacks involving chemical or biological WMD which consequently may result in the loss of hundreds or even thousands of lives. Therefore, hospitals continue to require substantial resources at the local, State, and national levels in order to be “truly” prepared.

  20. Standard test methods for chemical and mass spectrometric analysis of nuclear-grade gadolinium oxide (Gd2O3) powder

    CERN Document Server

    American Society for Testing and Materials. Philadelphia

    2006-01-01

    1.1 These test methods cover procedures for the chemical and mass spectrometric analysis of nuclear-grade gadolinium oxide powders to determine compliance with specifications. 1.2 The analytical procedures appear in the following order: Sections Carbon by Direct CombustionThermal Conductivity C1408 Test Method for Carbon (Total) in Uranium Oxide Powders and Pellets By Direct Combustion-Infrared Detection Method Total Chlorine and Fluorine by Pyrohydrolysis Ion Selective Electrode C1502 Test Method for Determination of Total Chlorine and Fluorine in Uranium Dioxide and Gadolinium Oxide Loss of Weight on Ignition 7-13 Sulfur by CombustionIodometric Titration Impurity Elements by a Spark-Source Mass Spectrographic C761 Test Methods for Chemical, Mass Spectrometric, Spectrochemical,Nuclear, and Radiochemical Analysis of Uranium Hexafluoride C1287 Test Method for Determination of Impurities In Uranium Dioxide By Inductively Coupled Plasma Mass Spectrometry Gadolinium Content in Gadolinium Oxid...

  1. Chemical speciation analysis and environmental behaviour of 127I and 129I

    Energy Technology Data Exchange (ETDEWEB)

    Hansen, Violeta

    2011-10-15

    Chemical speciation analysis of 129I and 127I as iodide, iodate and total inorganic iodine in seawater samples from the Baltic Proper, Skagerrak and Kattegat has been carried out. The important findings of this study are that the reduction of iodate and oxidation of iodide in Skagerrak and Kattegat may be a slow process while along the Baltic Sea surface water reduction of iodate is a relatively fast process. Although suboxic or anoxic condition are encountered in some of the Baltic Sea deep basins, the concentration of 129IO{sub 3}- increases with water depth indicating that the reduction of iodate in the oxygen deficient bottom water of the Baltic Sea is a slow process. Iodine chemical speciation analysis (as iodide, iodate and total iodine including inorganic and organic iodine species) in lake water samples collected from Denmark and southern Sweden has been carried out. Destruction of organic iodine was performed by alkaline oxidation using NaOH - NaClO at 100 deg. C and anion exchange chromatography was used for separation of iodide and iodate. Iodine-129 concentrations in the lakes ranged from 1.3 - 12.8 x109 at/L and show elevated concentrations in lakes located in southwest Jutland (Denmark), near the North Sea. Except the Skaersoe Lake, were the organic iodine - 127 accounts for 50% of the total iodine, iodide (both 129I and 127I) is the predominant species form in surface water of the studied lakes. An investigation was conducted in order to quantify the total aquatic iodine (129I and 127I as inorganic and organic iodine) from fresh water and seawater samples by adsorption onto activated charcoal and DEAE 32 cellulose followed by alkaline digestion or combustion. The results show that iodide from freshwater samples can easily be adsorbed onto activated charcoal. The sorption was not affected by the pH. The absorption capacity of iodate is low and reduces quickly when its concentration increases. Compared with activated charcoal, DEAE 32 cellulose showed

  2. Chemical speciation analysis and environmental behaviour of 127I and 129I

    Energy Technology Data Exchange (ETDEWEB)

    Hansen, Violeta

    2011-10-15

    Chemical speciation analysis of 129I and 127I as iodide, iodate and total inorganic iodine in seawater samples from the Baltic Proper, Skagerrak and Kattegat has been carried out. The important findings of this study are that the reduction of iodate and oxidation of iodide in Skagerrak and Kattegat may be a slow process while along the Baltic Sea surface water reduction of iodate is a relatively fast process. Although suboxic or anoxic condition are encountered in some of the Baltic Sea deep basins, the concentration of 129IO{sub 3}- increases with water depth indicating that the reduction of iodate in the oxygen deficient bottom water of the Baltic Sea is a slow process. Iodine chemical speciation analysis (as iodide, iodate and total iodine including inorganic and organic iodine species) in lake water samples collected from Denmark and southern Sweden has been carried out. Destruction of organic iodine was performed by alkaline oxidation using NaOH - NaClO at 100 deg. C and anion exchange chromatography was used for separation of iodide and iodate. Iodine-129 concentrations in the lakes ranged from 1.3 - 12.8 x109 at/L and show elevated concentrations in lakes located in southwest Jutland (Denmark), near the North Sea. Except the Skaersoe Lake, were the organic iodine - 127 accounts for 50% of the total iodine, iodide (both 129I and 127I) is the predominant species form in surface water of the studied lakes. An investigation was conducted in order to quantify the total aquatic iodine (129I and 127I as inorganic and organic iodine) from fresh water and seawater samples by adsorption onto activated charcoal and DEAE 32 cellulose followed by alkaline digestion or combustion. The results show that iodide from freshwater samples can easily be adsorbed onto activated charcoal. The sorption was not affected by the pH. The absorption capacity of iodate is low and reduces quickly when its concentration increases. Compared with activated charcoal, DEAE 32 cellulose showed

  3. Chemical analysis of turmeric from Minas Gerais, Brazil and comparison of methods for flavour free oleoresin

    Directory of Open Access Journals (Sweden)

    Cyleni R. A. Souza

    1998-01-01

    Full Text Available Chemical analysis of turmeric (Curcuma longa L cultivated in eight different cities in the state of Minas Gerais, Brazil was carried out. The levels of curcuminoid pigments varied from 1.4 to 6.14 g/100 g and of volatile oil from 0.97 to 7.55 mL/100 g (dry basis. Samples from Patrocínio, Arinos and Brasilândia contained higher pigment levels compared to the others. The sample from Patrocínio contained the highest volatile oil content. The mean levels of ethyl ether extract, protein, fiber, ash and starch were 8.51, 7.01, 7.22, 7.81 and 39.87 g/100 g dry basis, respectively. Laboratory extraction of flavour free oleoresin was performed in triplicate. A higher yield of pigment in the oleoresin was obtained when the volatile oil was extracted with water vapor and the oleoresin with ethanol. The oleoresin obtained was free of flavour and could be used in a wider range of food applications.Análise química de cúrcuma (Curcuma longa L provenientes de oito municípios do Estado de Minas Gerais - Brasil foi efetuada. Os teores (base seca de pigmentos curcuminóides variaram de 1,4 a 6,14 g/100 g e os de óleo volátil, de 0,97 a 7,55 mL/100 g. Amostras de Patrocínio, Arinos e Brasilândia continham os maiores teores de pigmentos e as de Patrocínio os maiores teores de óleos voláteis. Os teores médios (base seca de extrato etéreo, proteínas, fibras, cinzas e amido encontrados foram 8,51; 7,01; 7,22; 7,81 e 39,87 g/100 g, respectivamente. Com o objetivo de obter corante amarelo isento de flavor, métodos de extração em laboratório foram comparados em triplicata. Um maior rendimento de pigmento na oleoresina foi obtido extraindo-se o óleo volátil com vapor d'água e a oleoresina com etanol. A oleoresina obtida é isenta de flavor e pode ser utilizada em um número maior de aplicações na indústria alimentícia

  4. Determination of sulphide concentrates of ore copper by XRPD and chemical analysis

    Directory of Open Access Journals (Sweden)

    Cocić Mira B.

    2009-01-01

    Full Text Available Roasting process of sulphide copper concentrates in fluo-solid reactor is an oxidation process, and presents the first stage of copper concentrate processing in Copper Mining and Smelting Complex Bor, RTB Bor. Therefore, the importance of accurate and up to date process control is an apparent precondition for the correct treatment in the following stages and also for of high grade cathode copper. As concentrate is fed into the roaster, it is heated by a stream of hot air to about 590°C. The process takes place between solid and gaseous phases without the appearance of a liquid phase. The heat generated by the exothermic oxidation reaction of sulphur from cooper and iron minerals (chalcopyrite and pyrite is sufficient to carry out the entire process autogenously at temperature from 620 to 670°C. The temperature of sulphur firing which defines the start of roasting depends on physical traits, particle size of sulfides and characteristic product of oxidation. The obtained products of the roasting process are: calcine, ready for smelting in the furnace and gas-rich sulphure dioxide (SO2, well suited for the production of sulfuric acid. The relationship between the quantitative mineral composition of the charge and of the calcine directly points out to the efficiency of the roasting process in fluo-solid reactor. The amount of bornite and magnetite, resulting from the sulfide oxidation is the most important parameter. Hence, quantitative determination of mineral composition is of great interest. In this work, the results of the determination of quantitative mineral composition of the copper sulphide concentrate (charge and products of their roasting (calcine and overflow in fluo-solid reactor in the RTB Bor are presented. The aim was to compare the results of the iron, copper, sulfur and oxygen contents determined by two independent techniques, the chemical (HA and X-ray powder diffraction analysis (XRPD that is based on the quantitative mineral

  5. Chemical Composition by Neutron Activation Analysis (INAA) of Neo-Assyrian Palace Ware from Iraq, Syria and Israel

    OpenAIRE

    Hunt, Alice M W; Johannes H Sterba

    2013-01-01

    Neo-Assyrian Palace Ware is an 8th-7th century B.C.E. fine-ware which originated in Northern Mesopotamia and spread throughout the greater Levant. The mechanism by which Palace Ware moved across the Neo-Assyrian imperial landscape (trade or local imitation/emulation) is of great archaeological interest. This dataset provides chemical compositional data, generated using instrumental neutron activation analysis (INAA), for Palace Ware vessels from Nimrud and Nineveh, in the Assyrian imperial co...

  6. Validation and assessment of uncertainty of chemical tests as a tool for the reliability analysis of wastewater IPEN

    International Nuclear Information System (INIS)

    The validation of analytical methods has become an indispensable tool for the analysis in chemical laboratories, including being required for such accreditation. However, even if a laboratory using validated methods of analysis there is the possibility that these methods generate results discrepant with reality by making necessary the addition of a quantitative attribute (a value) which indicates the degree of certainty the extent or the analytical method used. This measure assigned to the result of measurement is called measurement uncertainty. We estimate this uncertainty with a level of confidence both direction, an analytical result has limited significance if not carried out proper assessment of its uncertainty. One of the activities of this work was to elaborate a program to help the validation and evaluation of uncertainty in chemical analysis. The program was developed with Visual Basic programming language and method of evaluation of uncertainty introduced the following concepts based on the GUM (Guide to the Expression of Uncertainty in Measurement). This evaluation program uncertainty measurement will be applied to chemical analysis in support of the characterization of the Nuclear Fuel Cycle developed by IPEN and the study of organic substances in wastewater associated with professional activities of the Institute. In the first case, primarily for the determination of total uranium and the second case for substances that were generated by human activities and that are contained in resolution 357/2005. As strategy for development of this work was considered the PDCA cycle to improve the efficiency of each step and minimize errors while performing the experimental part. The program should be validated to meet requirements of standards such as, for example, the standard ISO/IEC 17025. The application, it is projected to use in other analytical procedures of both the Nuclear Fuel Cycle and in the control program and chemical waste management of IPEN

  7. De Novo Assembly and Transcriptome Analysis of Wheat with Male Sterility Induced by the Chemical Hybridizing Agent SQ-1

    OpenAIRE

    Qidi Zhu; Yulong Song; Gaisheng Zhang; Lan Ju; Jiao Zhang; Yongang Yu; Na Niu; Junwei Wang; Shoucai Ma

    2015-01-01

    Wheat (Triticum aestivum L.), one of the world's most important food crops, is a strictly autogamous (self-pollinating) species with exclusively perfect flowers. Male sterility induced by chemical hybridizing agents has increasingly attracted attention as a tool for hybrid seed production in wheat; however, the molecular mechanisms of male sterility induced by the agent SQ-1 remain poorly understood due to limited whole transcriptome data. Therefore, a comparative analysis of wheat anther tra...

  8. Toxicogenomic Analysis Suggests Chemical-Induced Sexual Dimorphism in the Expression of Metabolic Genes in Zebrafish Liver

    OpenAIRE

    Xun Zhang; Choong Yong Ung; Siew Hong Lam; Jing Ma; Yu Zong Chen; Louxin Zhang; Zhiyuan Gong; Baowen Li

    2012-01-01

    Differential gene expression in two sexes is widespread throughout the animal kingdom, giving rise to sex-dimorphic gene activities and sex-dependent adaptability to environmental cues, diets, growth and development as well as susceptibility to diseases. Here, we present a study using a toxicogenomic approach to investigate metabolic genes that show sex-dimorphic expression in the zebrafish liver triggered by several chemicals. Our analysis revealed that, besides the known genes for xenobioti...

  9. Chemical composition distribution analysis of photoresist copolymers and influence on ArF lithographic performance

    Science.gov (United States)

    Momose, Hikaru; Yasuda, Atsushi; Ueda, Akifumi; Iseki, Takayuki; Ute, Koichi; Nishimura, Takashi; Nakagawa, Ryo; Kitayama, Tatsuki

    2007-03-01

    For getting information about the distribution of chemical composition, several model polymers were prepared under different polymerization conditions and were measured by critical adsorption point-liquid chromatography (CAP-LC). In the copolymer system of 8- and 9- (4-oxatricyclo[5.2.1.0 2,6]decane-3-one) acrylate (OTDA) and 2-ethyl-2-adamantyl methacrylate (EAdMA), the peak shapes of the CAP-LC chromatogram varied according to the polymerization condition although they indicated same molecular weight and averaged chemical composition. The difference of the CAP-LC elution curves was related to the chemical composition distribution of copolymers for CAP-LC measurement combined with proton nuclear magnetic resonance (1H-NMR). The terpolymers consisted of α-hydroxy-γ-butyrolactone methacrylate (GBLMA), 2-methyl-2-adamantyl methacrylate (MAdMA) and 1-hydroxy-3-adamantyl methacrylate (HAdMA) were prepared under various polymerization conditions. In the terpolymer system that had same molecular weight and average chemical composition, the solubility parameter (δ) and the dissolution rate were measured. The δ value and the dissolution rate curve were different among these terpolymers. It was suggested that the δ value and the chemical composition distribution of these terpolymers have a significant influence on the lithographic performance.

  10. 我国煤化工发展分析%China Coal Chemical Industry Development Analysis

    Institute of Scientific and Technical Information of China (English)

    李志龙; 陈明

    2011-01-01

    The paper stated the characteristics of the coal chemical and analyzed the challenges and opportunities of the coal chemical development in China.The coal chemical must stick to the principle of being in proportion and in order.We need pay close attenton to international markets of crude oil and chemical products and analyse carefully the market competitiveness of coal-base products.Actively promote coal production enterprises and chemical enterprise power-and-power union.%文章阐述了新型煤化工的特点,分析了中国发展煤化工面临的挑战和机遇。发展煤化工必须坚持适度、有序的原则,综合考虑社会投入,高度关注国际油价和石化产品市场,认真分析市场竞争力,积极推动煤炭生产企业与煤化工企业强强联合。

  11. Performance analysis of solar-assisted chemical heat-pump dryer

    Energy Technology Data Exchange (ETDEWEB)

    Fadhel, M.I. [Solar Energy Research Institute, Universiti Kebangsaan Malaysia, 43600 Bangi, Selangor (Malaysia); Faculty of Engineering and Technology, Multimedia University, Jalan Ayer Keroh Lama, 75450, Melaka (Malaysia); Sopian, K.; Daud, W.R.W. [Solar Energy Research Institute, Universiti Kebangsaan Malaysia, 43600 Bangi, Selangor (Malaysia)

    2010-11-15

    A solar-assisted chemical heat-pump dryer has been designed, fabricated and tested. The performance of the system has been studied under the meteorological conditions of Malaysia. The system consists of four main components: solar collector (evacuated tubes type), storage tank, solid-gas chemical heat pump unit and dryer chamber. A solid-gas chemical heat pump unit consists of reactor, condenser and evaporator. The reaction used in this study (CaCl2-NH{sub 3}). A simulation has been developed, and the predicted results are compared with those obtained from experiments. The maximum efficiency for evacuated tubes solar collector of 80% has been predicted against the maximum experiment of 74%. The maximum values of solar fraction from the simulation and experiment are 0.795 and 0.713, respectively, whereas the coefficient of performance of chemical heat pump (COP{sup h}) maximum values 2.2 and 2 are obtained from simulation and experiments, respectively. The results show that any reduction of energy at condenser as a result of the decrease in solar radiation will decrease the coefficient of performance of chemical heat pump as well as decrease the efficiency of drying. (author)

  12. New methods for toxicokinetic studies on chemicals carcinogens by means of analysis of DNA damage

    International Nuclear Information System (INIS)

    For investigating the potential carcinogenic properties of chemicals or for elucidating their mechanisms of activities, it is as important to determine their DNA damaging effects as it is to determine their mutagenicity. In the following, three methods will be presented which may be utilized to detect chemically induced DNA damage. These are the classical DNA filter elution procedure (AE), the in situ nick translation (NT), and the single cell microgel-electrophoresis (MGE) assay. Latter two methods have the advantage that they will allow genotoxic effects to be determined in many organs of the experimental animals, since only minute quantities of tissue are needed. Therefore it is possible to efficiently obtain data pertaining to the toxicokinetics of the test chemical which may be used for purposes of risk assessment. (orig.)

  13. Physico Chemical Analysis of Municipal Wastewater Discharge in Ganga River,Haridwar District of Uttarakhand, India

    Directory of Open Access Journals (Sweden)

    Saba Shirin

    2014-08-01

    Full Text Available This study was aimed to screen the water quality of Ganga River in Haridwar city, Uttarakhand, India. The study was conducted based on their water source, origin of pollution such as utilisation by human and animals. Monthly changes in physico-chemical parameters such as pH, Temperature, Total Dissolved Solids, Total Solids, Total Suspended Solids, Chemical Oxygen Demand, Dissolved oxygen, Biochemical Oxygen Demand and Volatile Suspended Solids were analyzed for a period of twoyear fromJanuary2010 toDecember 2011.The results of this study reveal the status of water quality of Ganga Riverit may helpful to protect the water resources and create awareness about the water pollution among the people living around the city.The results indicated thatphysico-chemical parameters of the water were within the permissible limits.

  14. World War I chemical weapons bunker engineering evaluation and cost analysis

    Energy Technology Data Exchange (ETDEWEB)

    Craig, C.A.; Crotteau, A.

    1995-12-31

    This paper provides a review of the US Army Corps of Engineers development and execution of a CERCLA chemical weapons and soil removal from two World War 1 underground test bunkers. The non-time critical removal action was completed from October 1994 to January 1995 in conjunction with Operation Safe Removal, Spring Valley, Washington, D.C. On January 5, 1993, a startled backhoe operator unearthed three 75mm artillery shells, exposing the legacy of a World War 1 (WWI) chemical weapons test facility in the midst of the nation`s capitol. That discovery, made in an exclusive residential neighborhood, prompted an intensive two year environmental cleanup. The Army immediately responded to the chemical ordnance threat, initiating Operation Safe Removal, a $20 million emergency response action and remedial investigation.

  15. Potential of Palm Olein as Green Lubricant Source: Lubrication Analysis and Chemical Characterisation

    International Nuclear Information System (INIS)

    Palm olein (POo) is widely used as edible oil in tropical countries. The lubrication properties and chemical compositions of POo being considered to be used as renewable raw material for bio lubricant synthesis. POo is suitable to be used directly as bio lubricant for medium temperature industrial applications. Palm olein has good viscosity index, oxidative stability, flash and fire point as a lubricant source. POo contains unsaturated triacylglycerols (TAG): Palmitin-Olein-Olein, POO (33.3 %), Palmitin-Olein-Palmitin, POP (29.6 %), which are very important to produce good lubricant properties. This unsaturated bond is preferable in chemical modification to produce bio lubricant. The chemical compositions of POo were tested by using high performance liquid chromatography (HPLC) and gas chromatography (GC) techniques. (author)

  16. Algorithms for three-dimensional chemical analysis via multi-energy synchrotron X-ray tomography

    Science.gov (United States)

    Ham, Kyungmin; Butler, Leslie G.

    2007-08-01

    The conversion of X-ray tomography images into three-dimensional chemical composition requires accurate mass absorption values, high-quality images, and a robust fitting algorithm. The least-squares fits of the images to a three-dimensional chemical composition can proceed with several different options such as minimal vs. over-determined and/or constrained parameters. This project has investigated the impact of XAFS features and a limited CCD dynamic range. These simulated results are compared to a recent experimental project in which synchrotron X-ray tomography was used to image a polymer blend, and from those images, calculated three-dimensional chemical composition maps of the two-component flame retardant, a brominated phthalimide dimer, Saytex ™ BT-93 and a synergist, antimony(III) oxide (Sb 2O 3).

  17. Numerical analysis of supersonic gas jets into liquid pools with or without chemical reaction using the SERAPHIM program

    International Nuclear Information System (INIS)

    Highlights: ► We perform numerical analysis on gas jet into liquid with or without reaction. ► We apply multi-fluid model and surface reaction model. ► Proposed model can reproduce behaviors of gas jet into liquid with reaction. - Abstract: A computer program called SERAPHIM has been developed to calculate multicomponent multiphase flow involving sodium-water chemical reaction in a steam generator of sodium cooled fast reactors. In this study, numerical analyses of supersonic gas jets into liquid pools with or without chemical reaction were performed to validate proposed numerical methods. The SERAPHIM program uses a multi-fluid model and a HSMAC method modified for compressible multiphase flows. An interfacial drag force was calculated from a newly constructed model. A surface reaction model, which has been developed by the authors, was applied to evaluate a mass generation rate by chemical reaction between a gas and liquid phase. As validation for a non-reaction problem, the experiment on horizontal supersonic air jet into water was analyzed. Numerical results showed that velocity of the injected air decreased by the effect of a interfacial drag force, and then the air went upward because of buoyancy. A horizontal penetration length of the air jet agreed with experimental results very well. On the other hand, we analyzed the experiment on vertical supersonic chlorine jet into Na–NaCl mixture. In this analysis, the injected gas disappeared at a certain height from chemical reaction. An estimated plume length showed good agreement with experimental data. The proposed numerical methods were found to be applicable to multiphase flow with supersonic gas jet and chemical reaction.

  18. Burden of disease and costs of exposure to endocrine disrupting chemicals in the European Union: an updated analysis.

    Science.gov (United States)

    Trasande, L; Zoeller, R T; Hass, U; Kortenkamp, A; Grandjean, P; Myers, J P; DiGangi, J; Hunt, P M; Rudel, R; Sathyanarayana, S; Bellanger, M; Hauser, R; Legler, J; Skakkebaek, N E; Heindel, J J

    2016-07-01

    A previous report documented that endocrine disrupting chemicals contribute substantially to certain forms of disease and disability. In the present analysis, our main objective was to update a range of health and economic costs that can be reasonably attributed to endocrine disrupting chemical exposures in the European Union, leveraging new burden and disease cost estimates of female reproductive conditions from accompanying report. Expert panels evaluated the epidemiologic evidence, using adapted criteria from the WHO Grading of Recommendations Assessment, Development and Evaluation Working Group, and evaluated laboratory and animal evidence of endocrine disruption using definitions recently promulgated by the Danish Environmental Protection Agency. The Delphi method was used to make decisions on the strength of the data. Expert panels consensus was achieved for probable (>20%) endocrine disrupting chemical causation for IQ loss and associated intellectual disability; autism; attention deficit hyperactivity disorder; endometriosis; fibroids; childhood obesity; adult obesity; adult diabetes; cryptorchidism; male infertility, and mortality associated with reduced testosterone. Accounting for probability of causation, and using the midpoint of each range for probability of causation, Monte Carlo simulations produced a median annual cost of €163 billion (1.28% of EU Gross Domestic Product) across 1000 simulations. We conclude that endocrine disrupting chemical exposures in the EU are likely to contribute substantially to disease and dysfunction across the life course with costs in the hundreds of billions of Euros per year. These estimates represent only those endocrine disrupting chemicals with the highest probability of causation; a broader analysis would have produced greater estimates of burden of disease and costs. PMID:27003928

  19. XLPM: efficient algorithm for the analysis of protein-protein contacts using chemical cross-linking mass spectrometry

    OpenAIRE

    Jaiswal, Mihir; Crabtree, Nathaniel Mark; Bauer, Michael A; Hall, Roger; Raney, Kevin D.; Boris L Zybailov

    2014-01-01

    Background Chemical cross-linking is used for protein-protein contacts mapping and for structural analysis. One of the difficulties in cross-linking studies is the analysis of mass-spectrometry data and the assignment of the site of cross-link incorporation. The difficulties are due to higher charges of fragment ions, and to the overall low-abundance of cross-link species in the background of linear peptides. Cross-linkers non-specific at one end, such as photo-inducible diazirines, may compl...

  20. Analysis of chemical factors affecting marine ecosystem around nuclear power plant

    Energy Technology Data Exchange (ETDEWEB)

    Chun, Kwan Sik; Choi, Yoon Dong; Chun, Ki Jeong; Kim, Jin Kyu; Jung, Kyeong Chai; Lee, Yeong Keun; Park, Hyo Kook [Korea Atomic Energy Res. Inst., Taejon (Korea, Republic of)

    1994-06-01

    The ecological data of the coastal area of Youngkwang nuclear power plant from 1987 to 1993 were comprehensively analyzed, and various physical and chemical properties of sea water and sediments were measured. Major factors affecting phytoplankton standing crops were suspended substances, nitrate, and silicate. The contents of iron, chromium, copper, and sulfur in sediments sampled from the discharge channel were slightly higher than those in the other areas. In order to qantify the chemical impacts on marine ecosystem, it is desirable that a systematic survey be made through the whole year cycle to assure the consistency and confidence of the related data. (Author).

  1. Ab initio analysis of magnetovolume versus chemical effects in CeRuSi and its hydride

    Science.gov (United States)

    Matar, Samir F.

    2007-03-01

    The change from heavy fermion to antiferromagnetic behavior of intermetallic system CeRuSi upon hydrogenation is addressed on bases of lattice expansion and chemical bonding effects within the density-functional theoretical framework using all electron scalar-relativistic augmented spherical wave method. While no magnetic moment develops in the 111 system, from total-energy differences, the hydride is found to be stable as an antiferromagnet in the ground state, in agreement with experiment. The role of anisotropic lattice expansion induced by hydrogen insertion is shown to be prevailing over the chemical bonding between hydrogen and the metallic species especially cerium.

  2. Analysis and classification of physical and chemical methods of fuel activation

    Directory of Open Access Journals (Sweden)

    Fedorchak Viktoriya

    2015-12-01

    Full Text Available The offered article explores various research studies, developed patents in terms of physical and chemical approaches to the activation of fuel. In this regard, national and foreign researches in the field of fuels activators with different principles of action were analysed, evaluating their pros and cons. The article also intends to classify these methods and compare them regarding diverse desired results and types of fuels used. In terms of physical and chemical influences on fuels and the necessity of making constructive changes in the fuel system of internal combustion engines, an optimal approach was outlined.

  3. Characterization of Denitrifying Phosphorus Removal Microorganisms in a Novel Two-Sludge Process by Combining Chemical with Microbial Analysis

    Directory of Open Access Journals (Sweden)

    Haiming Zou

    2014-01-01

    Full Text Available The present work focuses on the investigation of denitrifying phosphorus removal organisms (DPB in a novel two-sludge denitrifying phosphorus removal process by combining chemical with microbial analysis. When the two-sludge process operated stably over one year, good phosphorus (P release and P uptake performance of activated sludge samples collected from this process were present in anaerobic and anoxic conditions, respectively, via batch test, showing that the ratio of P release specific rate to P uptake specific rate was 1.31. The analysis of energy dispersive spectrometry (EDS showed that P content of activated sludge samples collected at the end of anoxic phase was 12.3% of dry weight, further demonstrating the existence of microorganisms responsible for phosphorus removal in this two-sludge process. From polymerase chain reaction-denaturing gradient gel electrophoresis (PCR-DGGE analysis, the presence of microorganisms mostly belonging to the phyla Firmicutes and Proteobacteria was observed, previously evidenced in the phosphorus removal wastewater treatment process. Fluorescence in situ hybridization (FISH quantitative analysis showed that Accumulibacter responsible for phosphorus removal was dominant in this two-sludge process, accounting for 69.7% of all bacteria in activated sludge. These results obtained from chemical and microbial analysis in this study suggested that denitrifying phosphorus removal microorganisms were completely enriched in the two-sludge process proposed here.

  4. Automated Chemical Analysis of Internally Mixed Aerosol Particles Using X-ray Spectromicroscopy at the Carbon K-Edge

    Energy Technology Data Exchange (ETDEWEB)

    Gilles, Mary K; Moffet, R.C.; Henn, T.; Laskin, A.

    2011-01-20

    We have developed an automated data analysis method for atmospheric particles using scanning transmission X-ray microscopy coupled with near edge X-ray fine structure spectroscopy (STXM/NEXAFS). This method is applied to complex internally mixed submicrometer particles containing organic and inorganic material. Several algorithms were developed to exploit NEXAFS spectral features in the energy range from 278 to 320 eV for quantitative mapping of the spatial distribution of elemental carbon, organic carbon, potassium, and noncarbonaceous elements in particles of mixed composition. This energy range encompasses the carbon K-edge and potassium L2 and L3 edges. STXM/NEXAFS maps of different chemical components were complemented with a subsequent analysis using elemental maps obtained by scanning electron microscopy coupled with energy dispersive X-ray analysis (SEM/EDX). We demonstrate the application of the automated mapping algorithms for data analysis and the statistical classification of particles.

  5. Towards an integrated biosensor array for simultaneous and rapid multi-analysis of endocrine disrupting chemicals

    International Nuclear Information System (INIS)

    Highlights: ► A multitask biosensor for the detection of endocrine disrupting chemicals is proposed. ► The sensing system employ an array of biological recognition elements. ► Amperometric and optical transduction methods are provided in an integrated biosensor together with flow control systems. ► The biosensing device results in an integrated, automatic and portable system for environmental and agrifood application. - Abstract: In this paper we propose the construction and application of a portable multi-purpose biosensor array for the simultaneous detection of a wide range of endocrine disruptor chemicals (EDCs), based on the recognition operated by various enzymes and microorganisms. The developed biosensor combines both electrochemical and optical transduction systems, in order to increase the number of chemical species which can be monitored. Considering to the maximum residue level (MRL) of contaminants established by the European Commission, the biosensor system was able to detect most of the chemicals analysed with very high sensitivity. In particular, atrazine and diuron were detected with a limit of detection of 0.5 nM, with an RSD% less than 5%; paraoxon and chlorpyrifos were revealed with a detection of 5 μM and 4.5 μM, respectively, with an RSD% less than 6%; catechol and bisphenol A were identified with a limit of detection of 1 μM and 35 μM respectively, with an RSD% less than 5%.

  6. Sustainability in the Design, Synthesis and Analysis of Chemical Engineering Processes 1st edition

    Science.gov (United States)

    This book preface explains the needs found by the book editors for assembling the state of the art of technical and scientific knowledge relevant to chemical engineering, sustainability, and sustainable uses of wastes and materials management, and to do so in an accessible and c...

  7. Chemical-genetic profile analysis of five inhibitory compounds in yeast

    Directory of Open Access Journals (Sweden)

    Alamgir Md

    2010-08-01

    Full Text Available Abstract Background Chemical-genetic profiling of inhibitory compounds can lead to identification of their modes of action. These profiles can help elucidate the complex interactions between small bioactive compounds and the cell machinery, and explain putative gene function(s. Results Colony size reduction was used to investigate the chemical-genetic profile of cycloheximide, 3-amino-1,2,4-triazole, paromomycin, streptomycin and neomycin in the yeast Saccharomyces cerevisiae. These compounds target the process of protein biosynthesis. More than 70,000 strains were analyzed from the array of gene deletion mutant yeast strains. As expected, the overall profiles of the tested compounds were similar, with deletions for genes involved in protein biosynthesis being the major category followed by metabolism. This implies that novel genes involved in protein biosynthesis could be identified from these profiles. Further investigations were carried out to assess the activity of three profiled genes in the process of protein biosynthesis using relative fitness of double mutants and other genetic assays. Conclusion Chemical-genetic profiles provide insight into the molecular mechanism(s of the examined compounds by elucidating their potential primary and secondary cellular target sites. Our follow-up investigations into the activity of three profiled genes in the process of protein biosynthesis provided further evidence concerning the usefulness of chemical-genetic analyses for annotating gene functions. We termed these genes TAE2, TAE3 and TAE4 for translation associated elements 2-4.

  8. Model Reduction in Chemical Engineering: Case studies applied to process analysis, design and operation

    NARCIS (Netherlands)

    Dorneanu, B.

    2011-01-01

    During the last decades, models have become widely used for supporting a broad range of chemical engineering activities, such as product and process design and development, process monitoring and control, real time optimization of plant operation or supply chain management. Although tremendous advan

  9. Analogies in the Teaching of Chemical Equilibrium: A Synthesis/Analysis of the Literature

    Science.gov (United States)

    Raviolo, Andres; Garritz, Andoni

    2009-01-01

    This paper presents a thorough literature review of the analogies used to teach chemical equilibrium. The main objective is to compile all the analogies that have been found to be of service to the teacher and the student. Additionally, we categorize and analyze analogies in relation to the following aspects: representation of the dynamic nature…

  10. Chemical analysis and biological testing of materials from the EDS coal liquefaction process: a status report

    Energy Technology Data Exchange (ETDEWEB)

    Later, D.W.; Pelroy, R.A.; Wilson, B.W.

    1984-05-01

    Representative process materials were obtained from the EDS pilot plant for chemical and biological analyses. These materials were characterized for biological activity and chemical composition using a microbial mutagenicity assay and chromatographic and mass spectrometric analytical techniques. The two highest boiling distillation cuts, as well as process solvent (PS) obtained from the bottoms recycle mode operation, were tested for initiation of mouse skin tumorigenicity. All three materials were active; the crude 800/sup 0 +/F cut was substantially more potent than the crude bottoms recycle PS or 750 to 800/sup 0/F distillate cut. Results from chemical analyses showed the EDS materials, in general, to be more highly alkylated and have higher hydroaromatic content than analogous SRC II process materials (no in-line process hydrogenation) used for comparison. In the microbial mutagenicity assays the N-PAC fractions showed greater activity than did the aliphatic hydrocarbon, hydroxy-PAH, or PAH fractions, although mutagenicity was detected in certain PAH fractions by a modified version of the standard microbial mutagenicity assay. Mutagenic activities for the EDS materials were lower, overall, than those for the corresponding materials from the SRC II process. The EDS materials produced under different operational modes had distinguishable differences in both their chemical constituency and biological activity. The primary differences between the EDS materials studied here and their SRC II counterparts used for comparison are most likely attributable to the incorporation of catalytic hydrogenation in the EDS process. 27 references, 28 figures, 27 tables.

  11. Towards an integrated biosensor array for simultaneous and rapid multi-analysis of endocrine disrupting chemicals

    Energy Technology Data Exchange (ETDEWEB)

    Scognamiglio, Viviana, E-mail: viviana.scognamiglio@mlib.ic.cnr.it [IC-CNR Istituto di Cristallografia, AdR1 Dipartimento Agroalimentare - Via Salaria Km 29.3 00015, Rome (Italy); Pezzotti, Italo; Pezzotti, Gianni; Cano, Juan; Manfredonia, Ivano [Biosensor S.r.l. - Via degli Olmetti 44 00060 Formello, Rome (Italy); Buonasera, Katia [IC-CNR Istituto di Cristallografia, AdR1 Dipartimento Agroalimentare - Via Salaria Km 29.3 00015, Rome (Italy); Arduini, Fabiana; Moscone, Danila; Palleschi, Giuseppe [Universita di Roma Tor Vergata, Dipartimento di Scienze e Tecnologie Chimiche - Via della Ricerca Scientifica 00133, Rome (Italy); Giardi, Maria Teresa [IC-CNR Istituto di Cristallografia, AdR1 Dipartimento Agroalimentare - Via Salaria Km 29.3 00015, Rome (Italy)

    2012-11-02

    Highlights: Black-Right-Pointing-Pointer A multitask biosensor for the detection of endocrine disrupting chemicals is proposed. Black-Right-Pointing-Pointer The sensing system employ an array of biological recognition elements. Black-Right-Pointing-Pointer Amperometric and optical transduction methods are provided in an integrated biosensor together with flow control systems. Black-Right-Pointing-Pointer The biosensing device results in an integrated, automatic and portable system for environmental and agrifood application. - Abstract: In this paper we propose the construction and application of a portable multi-purpose biosensor array for the simultaneous detection of a wide range of endocrine disruptor chemicals (EDCs), based on the recognition operated by various enzymes and microorganisms. The developed biosensor combines both electrochemical and optical transduction systems, in order to increase the number of chemical species which can be monitored. Considering to the maximum residue level (MRL) of contaminants established by the European Commission, the biosensor system was able to detect most of the chemicals analysed with very high sensitivity. In particular, atrazine and diuron were detected with a limit of detection of 0.5 nM, with an RSD% less than 5%; paraoxon and chlorpyrifos were revealed with a detection of 5 {mu}M and 4.5 {mu}M, respectively, with an RSD% less than 6%; catechol and bisphenol A were identified with a limit of detection of 1 {mu}M and 35 {mu}M respectively, with an RSD% less than 5%.

  12. Test results of chemical reactivity test (CRT) analysis of structural materials and explosives

    Energy Technology Data Exchange (ETDEWEB)

    Back, P.S.; Barnhart, B.V.; Walters, R.R.; Haws, L.D.; Collins, L.W.

    1980-03-21

    The chemical reactivity test, CRT, is a procedure used to screen the compatibility of component structure materials with explosives. This report contains the results of CRT materials evaluations conducted at Mound Facility. Data about materials combinations are catalogued both under the name of the explosive and the nonexplosive.

  13. Using Texas Instruments Emulators as Teaching Tools in Quantitative Chemical Analysis

    Science.gov (United States)

    Young, Vaneica Y.

    2011-01-01

    This technology report alerts upper-division undergraduate chemistry faculty and lecturers to the use of Texas Instruments emulators as virtual graphing calculators. These may be used in multimedia lectures to instruct students on the use of their graphing calculators to obtain solutions to complex chemical problems. (Contains 1 figure.)

  14. Identification of Chemical-Genetic Interactions via Parallel Analysis of Barcoded Yeast Strains.

    Science.gov (United States)

    Suresh, Sundari; Schlecht, Ulrich; Xu, Weihong; Miranda, Molly; Davis, Ronald W; Nislow, Corey; Giaever, Guri; St Onge, Robert P

    2016-01-01

    The Yeast Knockout Collection is a complete set of gene deletion strains for the budding yeast, Saccharomyces cerevisiae In each strain, one of approximately 6000 open-reading frames is replaced with a dominant selectable marker flanked by two DNA barcodes. These barcodes, which are unique to each gene, allow the growth of thousands of strains to be individually measured from a single pooled culture. The collection, and other resources that followed, has ushered in a new era in chemical biology, enabling unbiased and systematic identification of chemical-genetic interactions (CGIs) with remarkable ease. CGIs link bioactive compounds to biological processes, and hence can reveal the mechanism of action of growth-inhibitory compounds in vivo, including those of antifungal, antibiotic, and anticancer drugs. The chemogenomic profiling method described here measures the sensitivity induced in yeast heterozygous and homozygous deletion strains in the presence of a chemical inhibitor of growth (termed haploinsufficiency profiling and homozygous profiling, respectively, or HIPHOP). The protocol is both scalable and amenable to automation. After competitive growth of yeast knockout collection cultures, with and without chemical inhibitors, CGIs can be identified and quantified using either array- or sequencing-based approaches as described here. PMID:27587778

  15. Sustainability in the Design, Synthesis and Analysis of Chemical Engineering Processes 1st edition (Preface)

    Science.gov (United States)

    This book preface explains the needs found by the book editors for assembling the state of the art of technical and scientific knowledge relevant to chemical engineering, sustainability, and sustainable uses of wastes and materials management, and to do so in an accessible and c...

  16. Socio-economic analysis for the authorisation of chemicals under REACH: a case of very high concern?

    Science.gov (United States)

    Gabbert, Silke; Scheringer, Martin; Ng, Carla A; Stolzenberg, Hans-Christian

    2014-11-01

    Under the European chemicals' legislation, REACH, substances that are identified to be of "very high concern" will de facto be removed from the market unless the European Commission grants authorisations permitting specific uses. Companies who apply for an authorisation without demonstrating "adequate control" of the risks have to show by means of a socio-economic analysis (SEA) that positive impacts of use outweigh negative impacts for human health and ecosystems. This paper identifies core challenges where further in-depth guidance is urgently required in order to ensure that a SEA can deliver meaningful results and that it can effectively support decision-making on authorisation. In particular, we emphasise the need (i) to better guide the selection of tools for impact assessment, (ii) to explicitly account for stock pollution effects in impact assessments for persistent and very persistent chemicals, (iii) to define suitable impact indicators for PBT/vPvB chemicals given the lack of reliable information about safe concentration levels, (iv) to guide how impacts can be transformed into values for decision-making, and (v) to provide a well-balanced discussion of discounting of long-term impacts of chemicals. PMID:25220186

  17. Design and analysis of questionnaires for survey skills in chemical engineering

    Directory of Open Access Journals (Sweden)

    Susana Lucas

    2011-09-01

    Full Text Available 800x600 Normal 0 21 false false false CA X-NONE X-NONE The new reorganization of university education has involved relevant changes in teaching and learning methodologies in order to help students to learn more effectively and to develop important skills and competences demanded by the professional world. In this sense the new configuration of the degree in Chemical Engineering required the identification of the main general and transferable skills, the implementation of the new teaching and learning strategies necessary to achieve them and, in addition, an evaluation procedure for determining the importance and the degree of development of a student´s skills and competences. In this exercise, two obligatory chemical reactor engineering subjects of the still in effect Chemical Engineering degree were chosen as examples of competence-based learning disciplines. For each one, a significant group of transferable and specific skills were selected to be developed. The identification and selection of skills was made according to the recommendations of the European Federation of Chemical Engineering (EFCE together with the established requirements in the ministerial order for the new Chemical Engineering Degree (Ministerial order CIN/351/2009. In order to check the effectiveness of teaching strategies in helping students to acquire these abilities, specific questionnaires were designed. These tests allowed for the utility of the competences in question to be evaluated in terms of the students´ professional work as future chemical engineering graduates and also facilitated the perception of skill development acquired through the methodology implemented in these subjects. The results of the skill evaluation questionnaires revealed the importance that both university collectives (students and professors give to the development of transferable skills. These skills included the ability to communicate effectively (including in English, to work in

  18. Evaluating legacy contaminants and emerging chemicals in marine environments using adverse outcome pathways and biological effects-directed analysis.

    Science.gov (United States)

    Hutchinson, Thomas H; Lyons, Brett P; Thain, John E; Law, Robin J

    2013-09-30

    important scientific, economic and health challenges. In order to meet these challenges and pursue cost-effective scientific approaches that can provide evidence necessary to support policy needs (e.g. the European Marine Strategy Framework Directive), it is widely recognised that there is a need to (i) provide marine exposure assessments for priority contaminants using a range of validated models, passive samplers and biomarkers; (ii) integrate chemical monitoring data with biological effects data across spatial and temporal scales (including quality controls); and (iii) strengthen the evidence base to understand the relationship between exposure to complex chemical mixtures, biological and ecological impacts through integrated approaches and molecular data (e.g. genomics, proteomics and metabolomics). Additionally, we support the widely held view that (iv) that rather than increasing the analytical chemistry monitoring of large number of emerging contaminants, it will be important to target analytical chemistry towards key groups of chemicals of concern using effects-directed analysis. It is also important to evaluate to what extent existing biomarkers and bioassays can address various classes of emerging chemicals using the adverse outcome pathway (AOP) approach now being developed by the Organization for Economic Cooperation and Development (OECD) with respect to human toxicology and ecotoxicology.

  19. Evaluating legacy contaminants and emerging chemicals in marine environments using adverse outcome pathways and biological effects-directed analysis

    International Nuclear Information System (INIS)

    important scientific, economic and health challenges. In order to meet these challenges and pursue cost-effective scientific approaches that can provide evidence necessary to support policy needs (e.g. the European Marine Strategy Framework Directive), it is widely recognised that there is a need to (i) provide marine exposure assessments for priority contaminants using a range of validated models, passive samplers and biomarkers; (ii) integrate chemical monitoring data with biological effects data across spatial and temporal scales (including quality controls); and (iii) strengthen the evidence base to understand the relationship between exposure to complex chemical mixtures, biological and ecological impacts through integrated approaches and molecular data (e.g. genomics, proteomics and metabolomics). Additionally, we support the widely held view that (iv) that rather than increasing the analytical chemistry monitoring of large number of emerging contaminants, it will be important to target analytical chemistry towards key groups of chemicals of concern using effects-directed analysis. It is also important to evaluate to what extent existing biomarkers and bioassays can address various classes of emerging chemicals using the adverse outcome pathway (AOP) approach now being developed by the Organization for Economic Cooperation and Development (OECD) with respect to human toxicology and ecotoxicology

  20. Antibacterial effect of ginger (Zingiber officinale roscoe and bioactive chemical analysis using Gas chromatography mass spectrum

    Directory of Open Access Journals (Sweden)

    Hasanain Khaleel Shareef

    2016-05-01

    Full Text Available The objectives of this research was to determine the chemical composition of roscoe extract from methanol and evaluation of antibacterial activity. The phytochemical compound screened by GC-MS method. Forty eight bioactive phytochemical compounds were identified in the methanolic extract of Zingiber officinale. The identification of phytochemical compounds is based on the peak area, retention time molecular weight, molecular formula, MS Fragment-ions and pharmacological actions. GC-MS analysis of Zingiber officinale revealed the existence of the Octanal, 2-Naphthalenamine,1,2,4a,5,6,7,8,8a-octahydro-4a-methyl, 1-(Cyclopropyl-nitro-methyl-cyclopentanol, Endo-Borneol, Decanal, 1,2-15,16-Diepoxyhexadecane, Propanal,2-methyl-3-phenyl, Benzeneacetic acid ,4-(1H-1,2,3,4-tetrazol-1-yl, Ascaridole epoxide, 2-Methoxy-4-vinylphenol, 6-epi-shyobunol, Phenol,2-methoxy-5-(1-propenyl-,E, Alfa.-Copaene, 8-Isopropenyl-1,5-dimethyl-cyclodeca-1,5-diene, Bicyclo[3.1.0]hexane-6-methanol,2-hydroxy-1,4,4-trimethyl, 7-epi-cis-sesquisabinene hydrate, Alloaromadendrene, Benzene,1-(1,5-dimethyl-4-hexenyl-4-methyl, 1,3-Cyclohexadiene ,5-(1,5-dimethyl-4-hexenyl-2methyl-,[S-(R*,S*], Aromadendrene oxide, 1,6,10-Dodecatrien-3-ol,3,7,11-trimethyl-,(E, 4-((1H-3-Hydroxy-1-propenyl-2-methoxyphenol, Butan-2-one,4-(3-hydroxy-2-methoxyphenyl, Longipinocarveol,trans, Cholestan-3-ol,2-methylene-,(3ß,5α-, Bicyclo[4.4.0]dec-2-ene-4-ol,2-methyl-9-(prop-1-en-3-ol-2-yl-, Corymbolone, Estra-1,3,5(10-trien-17ß-ol, 1-Heptatriacotanol, Fenretinide, Folic acid, Spiro[4.5]decan-7-one,1,8-dimethyl-8,9-epoxy-4-isopropyl-, 7H-6,9a-Methano-4H-cyclopenta[9,10] cyclopropa[5,6]cyclodeca[1, Gingerol, 1b,4a-Epoxy-2H-cyclopenta[3,4]cyclopropa [8,9]cycloundec[1,2-b]o, Cyclopropa[5,6]-A-nor-5α-androstane-3,7-dione,3´,6ß-dihydro-17ß-h, Olean-12-ene-3,15,16,21,22,28-hexol,(3ß,15α,16α,21ß,22α-, Benz[e]azulen-3(3aH-one,4,6a,7,8,9,10,10a,10b-octahydro-3a,8,1, Naphthalene, decahydro-1-pentadecyl-, 13

  1. A novel inlet system for on-line chemical analysis of semi-volatile submicron particulate matter

    Directory of Open Access Journals (Sweden)

    P. Eichler

    2014-09-01

    Full Text Available We herein present the concept of a novel modular inlet system that allows using gas-phase analyzers for on-line chemical characterization of semi-volatile submicron particles. The "chemical analysis of aerosol on-line" (CHARON inlet consists of a gas-phase denuder for stripping off gas-phase analytes, an aerodynamic lens for particle enrichment in the sampling flow and a thermo-desorption unit for particle volatilization prior to chemical analysis. We coupled the CHARON inlet to a proton-transfer-reaction time-of-flight mass spectrometer (PTR-ToF-MS which quantitatively detects most organic analytes and ammonia. The combined set-up measures submicron organic and ammonium nitrate/sulfate particles online. Two proof-of-principle studies were carried out for demonstrating the analytical power of the new set-up in analyzing primarily emitted and secondarily generated particles. Oxygenated organics and their partitioning between the gas and the particulate phase were observed from the reaction of limonene with ozone. Abundant quasi-molecular ions of organic particulate constituents were observed when submicron particles were sampled from diluted mainstream cigarette smoke.

  2. Discrimination and chemical phylogenetic study of seven species of Dendrobium using infrared spectroscopy combined with cluster analysis

    Science.gov (United States)

    Luo, Congpei; He, Tao; Chun, Ze

    2013-04-01

    Dendrobium is a commonly used and precious herb in Traditional Chinese Medicine. The high biodiversity of Dendrobium and the therapeutic needs require tools for the correct and fast discrimination of different Dendrobium species. This study investigates Fourier transform infrared spectroscopy followed by cluster analysis for discrimination and chemical phylogenetic study of seven Dendrobium species. Despite the general pattern of the IR spectra, different intensities, shapes, peak positions were found in the IR spectra of these samples, especially in the range of 1800-800 cm-1. The second derivative transformation and alcoholic extracting procedure obviously enlarged the tiny spectral differences among these samples. The results indicated each Dendrobium species had a characteristic IR spectra profile, which could be used to discriminate them. The similarity coefficients among the samples were analyzed based on their second derivative IR spectra, which ranged from 0.7632 to 0.9700, among the seven Dendrobium species, and from 0.5163 to 0.9615, among the ethanol extracts. A dendrogram was constructed based on cluster analysis the IR spectra for studying the chemical phylogenetic relationships among the samples. The results indicated that D. denneanum and D. crepidatum could be the alternative resources to substitute D. chrysotoxum, D. officinale and D. nobile which were officially recorded in Chinese Pharmacopoeia. In conclusion, with the advantages of high resolution, speediness and convenience, the experimental approach can successfully discriminate and construct the chemical phylogenetic relationships of the seven Dendrobium species.

  3. Differential dynamic engagement within 24 SH3 domain: peptide complexes revealed by co-linear chemical shift perturbation analysis.

    Directory of Open Access Journals (Sweden)

    Elliott J Stollar

    Full Text Available There is increasing evidence for the functional importance of multiple dynamically populated states within single proteins. However, peptide binding by protein-protein interaction domains, such as the SH3 domain, has generally been considered to involve the full engagement of peptide to the binding surface with minimal dynamics and simple methods to determine dynamics at the binding surface for multiple related complexes have not been described. We have used NMR spectroscopy combined with isothermal titration calorimetry to comprehensively examine the extent of engagement to the yeast Abp1p SH3 domain for 24 different peptides. Over one quarter of the domain residues display co-linear chemical shift perturbation (CCSP behavior, in which the position of a given chemical shift in a complex is co-linear with the same chemical shift in the other complexes, providing evidence that each complex exists as a unique dynamic rapidly inter-converting ensemble. The extent the specificity determining sub-surface of AbpSH3 is engaged as judged by CCSP analysis correlates with structural and thermodynamic measurements as well as with functional data, revealing the basis for significant structural and functional diversity amongst the related complexes. Thus, CCSP analysis can distinguish peptide complexes that may appear identical in terms of general structure and percent peptide occupancy but have significant local binding differences across the interface, affecting their ability to transmit conformational change across the domain and resulting in functional differences.

  4. Analysis of chemical samples for environmental levels of radioactivity using a massively shielded 18% Ge(Li) system

    International Nuclear Information System (INIS)

    An environmental level gamma radioactivity analysis system has been assembled from a commercially available, high sensitivity, high resolution, low background Ge(Li) detector with associated electronics (without coincidence or anticoincidence) and massive shielding with old iron. A variety of chemicals have been examined as part of a background baseline survey using quantitative peak or gross gamma analysis of the Ge(Li) gamma ray spectrum from a two liter sample in a Marinelli beaker. Gamma peak analysis had a calculated sensitivity (for a 30 min count) of 0.01 to 0.21 pCi/g, depending on sample bulk density, for an isotope such as 137Cs. A similar sensitivity (0.1 pCi/g) was obtained by gross gamma analysis for any mixture of isotopes. A method for estimating the necessary integral background value for samples of different bulk densities was developed. The methods are capable of demonstrating existing natural radioactivity as shown by the 40K and uranium, thorium and their daughters observed in about 16% of the chemicals tested. Especially noticeable were 40K, 228Ac, 212Pb, 208Tl, 214Pb, and 214Bi. The levels and isotopes were similar to those found in soils and common salts. (orig.)

  5. Analysis of chemical samples for environmental levels of radioactivity using a massively shielded 18% Ge(Li) system

    Science.gov (United States)

    Blanchard, Fred A.; Lickly, Tim D.

    1984-01-01

    An environmental level gamma radioactivity analysis system has been assembled from a commercially available, high sensitivity, high resolution, low background Ge(Li) detector with associated electronics (without coincidence or anticoincidence) and massive shielding with old iron. A variety of chemicals have been examined as part of a background baseline survey using quantitative peak or gross gamma analysis of the Ge(Li) gamma ray spectrum from a two liter sample in a Marinelli beaker. Gamma peak analysis had a calculated sensitivity (for a 30 min count) of 0.01 to 0.21 pCi/g, depending on sample bulk density, for an isotope such as 137Cs. A similar sensitivity (0.1 pCi/g) was obtained by gross gamma analysis for any mixture of isotopes. A method for estimating the necessary integral background value for samples of different bulk densities was developed. The methods are capable of demonstrating existing natural radioactivity as shown by the 40K and uranium, thorium and their daughters observed in about 16% of the chemicals tested. Especially noticeable were 40K, 228Ac, 212Pb, 208Tl, 214Pb, and 214Bi. The levels and isotopes were similar to those found in soils and common salts.

  6. Exploitation of chemical profiles by conjugate variable analysis: application to the dating of a tropical ice core (Nevado Illimani, Bolivia)

    Science.gov (United States)

    Gay, M.; De Angelis, M.; Lacoume, J.-L.

    2013-06-01

    Ice core dating is a key parameter for the interpretation of the ice archives. However, the relationship between ice depth and age can generally not be easily established and requires to combine a large number of investigations and/or modeling effort. This paper presents a new approach of ice core dating based on conjugate variable (depth and spatial frequency) analysis of chemical profiles. The relationship between the depth of a given ice layer and the date it was deposited is determined using ion concentration depth profiles obtained along a one hundred-meters deep ice core recovered in the summit area of the Nevado Illimani (6350 m a.s.l.), located in the Eastern Bolivian Andes (16°37' S, 67°46' W). The results of Fourier conjugate analysis and wavelet tranforms are first compared. Both methods are applied to nitrate concentration depth profile. The resulting chronologies are checked by comparison with the multi-proxy year-by-year dating published by de Angelis et al. (2003) and with volcanic tie points, demonstrating the efficiency of Fourier conjugate analysis when tracking the natural variability of chemical proxies. The Fourier conjugate analysis is then applied to concentration depth profiles of seven other ions thus providing information on the suitability of each of them for dating studies of tropical Andean ice cores.

  7. Quantitative analysis of cell surface membrane proteins using membrane-impermeable chemical probe coupled with 18O labeling

    Science.gov (United States)

    Zhang, Haizhen; Brown, Roslyn N.; Qian, Wei-Jun; Monroe, Matthew E.; Purvine, Samuel O.; Moore, Ronald J.; Gritsenko, Marina A.; Shi, Liang; Romine, Margaret F; Fredrickson, James K.; Paša-Tolić, Ljiljana; Smith, Richard D.; Lipton, Mary S.

    2010-01-01

    We report a mass spectrometry-based strategy for quantitative analysis of cell surface membrane proteome changes. The strategy includes enrichment of surface membrane proteins using a membrane-impermeable chemical probe followed by stable isotope 18O labeling and LC-MS analysis. We applied this strategy for enriching membrane proteins expressed by Shewanella oneidensis MR-1, a gram-negative bacterium with known metal-reduction capability via extracellular electron transfer between outer membrane proteins and extracellular electron receptors. LC/MS/MS analysis resulted in the identification of about 400 proteins with 79% of them being predicted to be membrane localized. Quantitative aspects of the membrane enrichment were shown by peptide level 16O and 18O labeling of proteins from wild-type and mutant cells (generated from deletion of a type II secretion protein, GspD) prior to LC-MS analysis. Using a chemical probe labeled pure protein as an internal standard for normalization, the quantitative data revealed reduced abundances in ΔgspD mutant cells of many outer membrane proteins including the outer membrane c-cype cytochromes OmcA and MtrC, in agreement with previously investigation demonstrating that these proteins are substrates of the type II secretion system. PMID:20380418

  8. Assessment of chemical exchange in tryptophan–albumin solution through 19F multicomponent transverse relaxation dispersion analysis

    International Nuclear Information System (INIS)

    A number of NMR methods possess the capability of probing chemical exchange dynamics in solution. However, certain drawbacks limit the applications of these NMR approaches, particularly, to a complex system. Here, we propose a procedure that integrates the regularized nonnegative least squares (NNLS) analysis of multiexponential T2 relaxation into Carr–Purcell–Meiboom–Gill (CPMG) relaxation dispersion experiments to probe chemical exchange in a multicompartmental system. The proposed procedure was validated through analysis of 19F T2 relaxation data of 6-fluoro-DL-tryptophan in a two-compartment solution with and without bovine serum albumin. Given the regularized NNLS analysis of a T2 relaxation curve acquired, for example, at the CPMG frequency υCPMG = 125, the nature of two distinct peaks in the associated T2 distribution spectrum indicated 6-fluoro-DL-tryptophan either retaining the free state, with geometric mean */multiplicative standard deviation (MSD) = 1851.2 ms */1.51, or undergoing free/albumin-bound interconversion, with geometric mean */MSD = 236.8 ms */1.54, in the two-compartment system. Quantities of the individual tryptophan species were accurately reflected by the associated T2 peak areas, with an interconversion state-to-free state ratio of 0.45 ± 0.11. Furthermore, the CPMG relaxation dispersion analysis estimated the exchange rate between the free and albumin-bound states in this fluorinated tryptophan analog and the corresponding dissociation constant of the fluorinated tryptophan–albumin complex in the chemical-exchanging, two-compartment system

  9. Assessment of chemical exchange in tryptophan–albumin solution through {sup 19}F multicomponent transverse relaxation dispersion analysis

    Energy Technology Data Exchange (ETDEWEB)

    Lin, Ping-Chang, E-mail: pingchang.lin@howard.edu [Howard University, Department of Radiology, College of Medicine (United States)

    2015-06-15

    A number of NMR methods possess the capability of probing chemical exchange dynamics in solution. However, certain drawbacks limit the applications of these NMR approaches, particularly, to a complex system. Here, we propose a procedure that integrates the regularized nonnegative least squares (NNLS) analysis of multiexponential T{sub 2} relaxation into Carr–Purcell–Meiboom–Gill (CPMG) relaxation dispersion experiments to probe chemical exchange in a multicompartmental system. The proposed procedure was validated through analysis of {sup 19}F T{sub 2} relaxation data of 6-fluoro-DL-tryptophan in a two-compartment solution with and without bovine serum albumin. Given the regularized NNLS analysis of a T{sub 2} relaxation curve acquired, for example, at the CPMG frequency υ{sub CPMG} = 125, the nature of two distinct peaks in the associated T{sub 2} distribution spectrum indicated 6-fluoro-DL-tryptophan either retaining the free state, with geometric mean */multiplicative standard deviation (MSD) = 1851.2 ms */1.51, or undergoing free/albumin-bound interconversion, with geometric mean */MSD = 236.8 ms */1.54, in the two-compartment system. Quantities of the individual tryptophan species were accurately reflected by the associated T{sub 2} peak areas, with an interconversion state-to-free state ratio of 0.45 ± 0.11. Furthermore, the CPMG relaxation dispersion analysis estimated the exchange rate between the free and albumin-bound states in this fluorinated tryptophan analog and the corresponding dissociation constant of the fluorinated tryptophan–albumin complex in the chemical-exchanging, two-compartment system.

  10. Engineering evaluation/cost analysis for the proposed management of contaminated water impounded at the Weldon Spring chemical plant area

    International Nuclear Information System (INIS)

    This engineering evaluation/cost analysis (EE/CA) report has been prepared to support the proposed removal action for managing contaminated surface waters impounded at the chemical plant area of the Weldon Spring site, located near Weldon Spring, Missouri. The US Department of Energy is responsible for cleanup activities at the site under its Surplus Facilities Management Program (SFMP). The major goals of SFMP are to eliminate potential hazards to human health and the environment that are associated with contamination at SFMP sites and to make surplus real property available for other uses, to the extent possible. The objectives of this EE/CA report are to identify the cleanup as a removal action, document the selection of a response that will mitigate the potential release of radioactive or chemical contaminants from the impounded waters into the nearby environment, and address environmental impacts associated with the proposed action. 41 refs., 8 figs., 8 tabs

  11. Risk Analysis Of Collision Between Passenger Ferry And Chemical Tanker In The Western Zone Of The Baltic Sea

    Directory of Open Access Journals (Sweden)

    Przywarty Marcin

    2015-04-01

    Full Text Available This paper presents assumptions and process of the forming of a risk assessment model for collision between a passenger ferry departing from or approaching port of Świnoujście and a chemical tanker carrying a dangerous cargo. In order to assess navigational safety on the basis of data obtained from AIS system, were prepared probabilistic domains of ships, which made it possible to estimate number of navigational incidents as well as their spatial distribution, that consequently allowed to determine potentially dangerous areas. The next phase was formulation of a simulative model intended for the calculating of probability of collision between the ferry and chemical tanker as well as the determining of characteristic scenarios for such collision. This paper presents also an analysis of consequences of the collision with taking into consideration a damage of cargo tanks.

  12. Search for Chemical Biomarkers on Mars Using the Sample Analysis at Mars Instrument Suite on the Mars Science Laboratory

    Science.gov (United States)

    Glavin, D. P.; Conrad, P.; Dworkin, J. P.; Eigenbrode, J.; Mahaffy, P. R.

    2011-01-01

    One key goal for the future exploration of Mars is the search for chemical biomarkers including complex organic compounds important in life on Earth. The Sample Analysis at Mars (SAM) instrument suite on the Mars Science Laboratory (MSL) will provide the most sensitive measurements of the organic composition of rocks and regolith samples ever carried out in situ on Mars. SAM consists of a gas chromatograph (GC), quadrupole mass spectrometer (QMS), and tunable laser spectrometer to measure volatiles in the atmosphere and released from rock powders heated up to 1000 C. The measurement of organics in solid samples will be accomplished by three experiments: (1) pyrolysis QMS to identify alkane fragments and simple aromatic compounds; pyrolysis GCMS to separate and identify complex mixtures of larger hydrocarbons; and (3) chemical derivatization and GCMS extract less volatile compounds including amino and carboxylic acids that are not detectable by the other two experiments.

  13. K-targeted metabolomic analysis extends chemical subtraction to DESIGNER extracts: selective depletion of extracts of hops (Humulus lupulus).

    Science.gov (United States)

    Ramos Alvarenga, René F; Friesen, J Brent; Nikolić, Dejan; Simmler, Charlotte; Napolitano, José G; van Breemen, Richard; Lankin, David C; McAlpine, James B; Pauli, Guido F; Chen, Shao-Nong

    2014-12-26

    This study introduces a flexible and compound targeted approach to Deplete and Enrich Select Ingredients to Generate Normalized Extract Resources, generating DESIGNER extracts, by means of chemical subtraction or augmentation of metabolites. Targeting metabolites based on their liquid-liquid partition coefficients (K values), K targeting uses countercurrent separation methodology to remove single or multiple compounds from a chemically complex mixture, according to the following equation: DESIGNER extract = total extract ± target compound(s). Expanding the scope of the recently reported depletion of extracts by immunoaffinity or solid phase liquid chromatography, the present approach allows a more flexible, single- or multi-targeted removal of constituents from complex extracts such as botanicals. Chemical subtraction enables both chemical and biological characterization, including detection of synergism/antagonism by both the subtracted targets and the remaining metabolite mixture, as well as definition of the residual complexity of all fractions. The feasibility of the DESIGNER concept is shown by K-targeted subtraction of four bioactive prenylated phenols, isoxanthohumol (1), 8-prenylnaringenin (2), 6-prenylnaringenin (3), and xanthohumol (4), from a standardized hops (Humulus lupulus L.) extract using specific solvent systems. Conversely, adding K-targeted isolates allows enrichment of the original extract and hence provides an augmented DESIGNER material. Multiple countercurrent separation steps were used to purify each of the four compounds, and four DESIGNER extracts with varying depletions were prepared. The DESIGNER approach innovates the characterization of chemically complex extracts through integration of enabling technologies such as countercurrent separation, K-by-bioactivity, the residual complexity concepts, as well as quantitative analysis by (1)H NMR, LC-MS, and HiFSA-based NMR fingerprinting. PMID:25437744

  14. Quantum chemical analysis for the formation of glycine in the interstellar medium

    Institute of Scientific and Technical Information of China (English)

    Amresh Singh; Shivani; Alka Misra; Poonam Tandon

    2013-01-01

    Glycine (C2H5NO2) was the first amino acid to be detected in space by the stardust space probe in Comet Wild2,and is used by living organisms to make proteins.We discuss three different reaction paths for the formation of glycine in interstellar space from some simpler molecules detected in the interstellar medium.The possibility of the formation of glycine in interstellar space is considered by radicalradical and radical-molecule interaction schemes using quantum chemical calculations with density functional theory at the B3LYP/6-31G (d,p) level.In the chemical pathways we discuss,a few reactions are found to be totally exothermic and barrierless while others are endothermic with a very small reaction barrier,thus giving rise to a high probability of forming glycine in interstellar space.

  15. Top-cited Articles in Chemical Engineering in Science Citation Index Expanded: A Bibliometric Analysis

    Institute of Scientific and Technical Information of China (English)

    Yuh-Shan Ho

    2012-01-01

    This study aimed to identify and to analyze characteristics of top-cited articles published in the Web of Science chemical engineering subject category from 1899 to 2011. Articles that have been cited more than 100 times were assessed regarding publication outputs, and distribution of outputs in journals. Five bibliometric indica- tors were used to evaluate source countries, institution and authors. A new indicator, Y-index, was created to assess quantity and quality of contribution to articles. Results showed that 3828 articles, published between 1931 and 2010, had been cited at least 100 times. Among them 54% published before 1991, and 49% top-cited articles originated from US. The top eight productive institutions were all located in US. The top journals were Journal of Catalysis, AIChE Journal, Chemical Engineering Science and Journal of Membrane Science. Y-index was successfully ap- plied to evaluate publication character of authors, institutions, and countries/regions.

  16. Analysis of Surface Chemistry and Detector Performance of Chemically Process CdZnTe crystals

    Energy Technology Data Exchange (ETDEWEB)

    HOSSAIN, A.; Yang, G.; Sutton, J.; Zergaw, T.; Babalola, O. S.; Bolotnikov, A. E.; Camarda. ZG. S.; Gul, R.; Roy, U. N., and James, R. B.

    2015-10-05

    The goal is to produce non-conductive smooth surfaces for fabricating low-noise and high-efficiency CdZnTe devices for gamma spectroscopy. Sample preparation and results are discussed. The researachers demonstrated various bulk defects (e.g., dislocations and sub-grain boundaries) and surface defects, and examined their effects on the performance of detectors. A comparison study was made between two chemical etchants to produce non-conductive smooth surfaces. A mixture of bromine and hydrogen peroxide proved more effective than conventional bromine etchant. Both energy resolution and detection efficiency of CZT planar detectors were noticeably increased after processing the detector crystals using improved chemical etchant and processing methods.

  17. La Popala creek: quality analysis of water from some physical - chemical, microbiological variables and aquatic macroinvertebrates

    International Nuclear Information System (INIS)

    The Popala creek supplies water to the people of Bolombolo in Venecia municipality in Antioquia, Colombia. In November 14th and 28th of 2009, four sampling station were located along the creek, to measure five sets of variables: physico- chemical, microbiological, aquatic macroinvertebrate, biological indicators and biotic index BMWP.Physico- chemical variables, aquatic macroinvertebrates and index BMWP indicate good environmental conditions in station 2, located about 150 m from the headwaters (station 1). On the other hand, Station 4, located near to the Cauca River, exhibits deterioration in water quality. Stations 3 and 4 displayed high levels of fecal coliforms. However, the samples taken from Bolombolo's water supply network indicate the water of the aqueduct is adequate for human consumption.

  18. Analysis Of Names Of Organic Chemical Compounds By Using Parser Combinators And The Generative Lexicon Theory

    Directory of Open Access Journals (Sweden)

    Marcio de Souza Dias

    2011-11-01

    Full Text Available This work proposes OCLAS (Organic Chemistry Language Ambiguity Solver, an automatic system to analyze syntactically and semantically Organic Chemistry compound names and to generate the pictures of their chemical structures. If both parses detect that the input name corresponds to a theoreticallypossible organic chemical compound, the system generates its molecular structure picture, whether or not the name respects the current official nomenclature. This capacity of treating even names which, in spite of do not respect the constraints of the official nomenclatures, correspond to theoretically possible organic compound, represents an advance of OCLAS compared to other existing systems. OCLAS counts on the following tools: Generative Lexicon Theory (GLT, Parser Combinators and the Language Clean and an extension of the Xymtec package of Latex. The implemented system represents a helpful and friendly utilitarian as an automatic Organic Chemistry instructor.

  19. Analysis Of Names Of Organic Chemical Compounds By Using Parser Combinators And The Generative Lexicon Theory

    Directory of Open Access Journals (Sweden)

    Márcio de Souza Dias

    2011-10-01

    Full Text Available This work proposes OCLAS (Organic Chemistry Language Ambiguity Solver, an automatic system to analyze syntactically and semantically Organic Chemistry compound names and to generate the pictures of their chemical structures. If both parses detect that the input name corresponds to a theoretically possible organic chemical compound, the system generates its molecular structure picture, whether or not the name respects the current official nomenclature. This capacity of treating even names which, in spite of do not respect the constraints of the official nomenclatures, correspond to theoretically possible organic compound, represents an advance of OCLAS compared to other existing systems. OCLAS counts on the following tools: Generative Lexicon Theory (GLT, Parser Combinators and the Language Clean and an extension of the Xymtec package of Latex. The implemented system represents a helpful and friendly utilitarian as an automatic Organic Chemistry instructor.

  20. Sensitivity analysis of silicon nanowire chemical sensor based on its geometry and the operating temperature

    Science.gov (United States)

    Jayachandran Nair, Deepthi

    Silicon Nano Wires (SiNW) have been used in recent times as major building block in various nano devices like sensors, FETs etc. SiNW devices have also manifested many advantages over nano tube (NT) devices such as their fabrication in today's silicon world. Chemical sensor based on SiNW changes its conductivity when the target molecules are captured by the receptors spread across the nano wire (NW). Chemical sensitivity, which is defined as the change in conductance, is analyzed analytically to see how it is affected by different parameters. The sensitivity of the sensor based on the length of the SiNW is verified from previous works and the temperature which has not been considered before as an important parameter in the sensor performance are taken into account to see how it affects the sensitivity of the sensor.

  1. Analysis of marine ecological compensation for environmental risk caused by chemical spill based on game theory

    Institute of Scientific and Technical Information of China (English)

    Zhang Jiwei; Yang Zhifeng; Huang Xinyu

    2009-01-01

    The problem of marine environmental risk is ultimately the result of game theory between the marine environmental managers and the enterprise of potential environmental risk.This paper analyzes the internal economic relationship that whether the "protection" policy is applied between the protection action of marine environmental managers and the chemical enterprise, The result shows that the key factor whether the enterprise adopt the "protection" policy or not is the amount of penalty and the government's cost of execution, and the compulsive ecological compensation is obligatory from the angle of stimulating the enterprise of canontcal action and adopting the "protection" policy.To build the ecological compensation mechanism based on the environmental risk will effectively improve the level of management in sea area and decrease the probability of chemical spill.

  2. Antibacterial and preliminary phytochemical and physico-chemical analysis of Eucalyptus citriodora Hk leaf.

    Science.gov (United States)

    Vaghasiya, Y; Nair, R; Chanda, S

    2008-06-15

    The present communication deals with some studies on the antibacterial, physico-chemical and phytochemical parameters of different extracts of Eucalyptus citriodora leaf. The antibacterial study was performed using the agar ditch method on some clinically important bacteria, namely Pseudomonas pseudoalcaligenes, Proteus vulgaris, Citrobacter freundii, Staphylococcus subflava, Bacillus megaterium, and Enterobacter aerogenes. Physico-chemical parameters namely water, methanol, 1,4-dioxane, DMF, acetone soluble extractives, total ash, melting point, and pH were determined according to pharmacopoeial procedures. Methanol gave the maximum extract while it was minimum in water. Phytochemical parameters were screened for alkaloids, tannins, cardiac glycosides, saponins, steroids and flavonoids. Tannins and flavonoids gave positive results, while steroids and glycosides were absent. The most susceptible bacteria was C. freundii, while the most resistant was P. vulgaris. PMID:18569717

  3. B36 borophene as an electronic sensor for formaldehyde: Quantum chemical analysis

    Science.gov (United States)

    Shahbazi Kootenaei, Amirhossein; Ansari, Goodarz

    2016-08-01

    Pristine carbon nanotubes and graphene show great sensitivity toward several lethal gases but cannot identify some extremely toxic chemicals such as formaldehyde (HCOH). Recent successful synthesis of all-boron graphene-like sheets attracted strong interest in exploring their possible applications. Herein, we inspected the potential application of B36 borophene sheet as a sensor for HCOH detection, using density functional theory computations. Different theoretical levels including B97D and Minnesota 06 functionals with different basis sets were employed. It was predicted that the electrical conductivity of B36 borophene significantly increases at the presence of HCOH molecules, thereby generating an electrical signal. The electrical signal is increased by increasing the number of adsorbed HCOH molecules, indicating that this sensor is sensitive to the concentration (or pressure) of HCOH gas. These results suggest that the pristine borophene may be used in the HCOH chemical sensors.

  4. Ultrafast multidimensional Laplace NMR for a rapid and sensitive chemical analysis

    Science.gov (United States)

    Ahola, Susanna; Zhivonitko, Vladimir V.; Mankinen, Otto; Zhang, Guannan; Kantola, Anu M.; Chen, Hsueh-Ying; Hilty, Christian; Koptyug, Igor V.; Telkki, Ville-Veikko

    2015-09-01

    Traditional nuclear magnetic resonance (NMR) spectroscopy relies on the versatile chemical information conveyed by spectra. To complement conventional NMR, Laplace NMR explores diffusion and relaxation phenomena to reveal details on molecular motions. Under a broad concept of ultrafast multidimensional Laplace NMR, here we introduce an ultrafast diffusion-relaxation correlation experiment enhancing the resolution and information content of corresponding 1D experiments as well as reducing the experiment time by one to two orders of magnitude or more as compared with its conventional 2D counterpart. We demonstrate that the method allows one to distinguish identical molecules in different physical environments and provides chemical resolution missing in NMR spectra. Although the sensitivity of the new method is reduced due to spatial encoding, the single-scan approach enables one to use hyperpolarized substances to boost the sensitivity by several orders of magnitude, significantly enhancing the overall sensitivity of multidimensional Laplace NMR.

  5. Analysis of Physical andChemical Characteristics and Influence Factors of UCG

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    Based on the UCG(underground coal gasification) theory, the “three zones” which are oxidization zone,reduction zone, and drying zone, were divided; physical and chemical properties of each zone were analyzed. Fac-tors, such as temperature, rate of water pouring, quantity of air blast, thickness of coal seam, and the operationpressure were discussed. Among the influencing factors, the temperature is the most important one.

  6. Chemical Analysis and Antioxidant Activity in vitro of Polysaccharides Extracted from Lower Grade Green Tea

    OpenAIRE

    Ping Chen; Yongjun Zhang; Liyun Zhu; Hui Jin; Gaofan Zhang; Dongyang Su; Jia Li

    2013-01-01

    Tea is a well-known and important agricultural product in the world. The Crude Polysaccharides from tea leaves (CP) probably have good antioxidant activities. However, whether or not the antioxidant abilities of CP depend on tea polyphenols in the CP is not understanded. In this study, four CP fractions (TPF30, TPF50, TPF70 and TPF90) were isolated from CP and their antioxidant activities were compared. Meanwhile, Chemical and physical characteristics of CP and four CP fractions were investig...

  7. Chemical analysis of uranium-niobium alloys by wavelength dispersive spectroscopy at the sigma complex

    Energy Technology Data Exchange (ETDEWEB)

    Papin, Pallas A.

    2012-06-01

    Uranium-niobium alloys play an important role in the nation's nuclear stockpile. It is possible to chemically quantify this alloy at a micron scale by using a technique know as wavelength dispersive spectroscopy. This report documents how this technique was used and how it is possible to reproduce measurements of this type. Discussion regarding the accuracy and precision of the measurements, the development of standards, and the comparison of different ways to model the matrices are all presented.

  8. Chemical analysis of selected pothole water sources in Southwestern National Parks, Monuments, and Recreation Areas

    Energy Technology Data Exchange (ETDEWEB)

    Gladney, E.S.; Ferenbaugh, R.W.; Bell, M.G.; Burns, C.; Morgan, J.D.; Nickell, E.J. [Los Alamos National Lab., NM (United States); Graham, T. [US Department of the Interior, National Park Service (United States)

    1993-10-01

    Environmental data related to the evaluation of inorganic air pollution input to pothole ecosystems in the desert Southwest have been collected over the past several years. Chemical composition of pothole waters and associated sediments are reported. The enrichment factor approach has been applied to the sediments in an effort to identify elemental levels that diverge from mean crustal abundances. These data provide a baseline for determining changes in elemental concentration and enrichment status in the future.

  9. Chemical, Corrosion and Topographical Analysis of Stainless Steel Implants after Different Implantation Periods

    OpenAIRE

    Chrzanowski, Wojciech; Armitage, David Andrew; Knowles, Jonathan Campbell; Szade, Jacek; Korlacki, Wojciech; Marciniak, Jan

    2008-01-01

    Abstract The aim of this work is to examine the corrosion properties, chemical composition, and material?implant interaction after different periods of implantation of plates used to correct funnel chest. The implants are made of 316L stainless steel. Examinations are carried out on three implants: new (nonimplanted) and two implanted for 29 and 35 months. The corrosion study reveals that in the potential range that could occur in the physiological condition the new bar has the low...

  10. CHEMICAL, PHYSICAL AND SENSORY ANALYSIS OF ACTIVITY DIFFERENT YEAST SPECIES ON IDENTICAL SUBSTRATE IN WINE PRODUCTION

    OpenAIRE

    Vladimír Vietoris; Hana Balková,Tatiana Bojňanská; Ľubomír Bennár; Peter Czako

    2013-01-01

    Rizling vlašský is the second most important variety in Slovakia. The science of wine production includes a summary of knowledge and experience in the field of grape growing and wine making, or the production of different types of wines using specific methods of production. Wine quality is the result of the interaction between yeast, bacteria and microscopic funguses. In this research, we studied the effects of active dry wine yeasts on chemical, physical and sensory parameters in wine produc...

  11. Environmental chemicals and changes in sex ratio: analysis over 250 years in finland.

    OpenAIRE

    Vartiainen, T; Kartovaara, L; Tuomisto, J

    1999-01-01

    It has been proposed that environmental chemicalization is responsible for the recent decline in male ratio, but these speculations are based on statistics going back only a few decades. The objective of this study was to evaluate whether Finnish long-term data are compatible with the hypothesis that the decrease in the ratio of male to female births in industrial countries is caused by environmental factors. We analyzed the sex ratio of births from the files of Statistics Finland and all liv...

  12. Analysis of the relationship between the structure and aromatic properties of chemical compounds.

    Science.gov (United States)

    Debska, Barbara; Guzowska-Swider, Barbara

    2003-04-01

    This paper presents the results of research on the relationship between the structure and odour properties of a selection of chemical compounds. The research concerns five groups of esters, each with a different smell: almond, apricot, apple, pineapple and rose. The supposed relationship between the smell and certain selected attributes of each molecule was examined by various pattern recognition techniques using programs developed in the Department of Computer Chemistry at Rzeszów University of Technology.

  13. Motif analysis for small-number effects in chemical reaction dynamics

    Science.gov (United States)

    Saito, Nen; Sughiyama, Yuki; Kaneko, Kunihiko

    2016-09-01

    The number of molecules involved in a cell or subcellular structure is sometimes rather small. In this situation, ordinary macroscopic-level fluctuations can be overwhelmed by non-negligible large fluctuations, which results in drastic changes in chemical-reaction dynamics and statistics compared to those observed under a macroscopic system (i.e., with a large number of molecules). In order to understand how salient changes emerge from fluctuations in molecular number, we here quantitatively define small-number effect by focusing on a "mesoscopic" level, in which the concentration distribution is distinguishable both from micro- and macroscopic ones and propose a criterion for determining whether or not such an effect can emerge in a given chemical reaction network. Using the proposed criterion, we systematically derive a list of motifs of chemical reaction networks that can show small-number effects, which includes motifs showing emergence of the power law and the bimodal distribution observable in a mesoscopic regime with respect to molecule number. The list of motifs provided herein is helpful in the search for candidates of biochemical reactions with a small-number effect for possible biological functions, as well as for designing a reaction system whose behavior can change drastically depending on molecule number, rather than concentration.

  14. Chemical and biological flocculation process to treat municipal sewage and analysis of biological function

    Institute of Scientific and Technical Information of China (English)

    XIA Si-qing; YANG Dian-hai; XU Bin; ZHAO Jian-fu

    2005-01-01

    The pilot-scale experimental apparatus and the procedure of the chemical and biological flocculation process to verify the feasibility in treating Shanghai municipal sewage were introduced in this paper. In addition, the biological function of the process was discussed. The results of optimal running showed that in the reaction tank, the concentration of mixed liquor suspended solid(MLSS) was2 g/L, hydraulic retention time(HRT) was 35 min, dosage of liquid polyaluminium chloride(PAC) was 60 mg/L, and the concentration of polyacrylamide(PAM) was 0.5 mg/L. The effluent average concentrations of CODcr, TP, SS and BOD5 were 50 mg/L, 0.62 mg/L, 18mg/L, and 17 mg/L, respectively. These were better than the designed demand. In addition, the existence of biological degradation in this system was proven by several methods. The removal efficiencies of the chemical and biological flocculation process were 20% higher than that of the chemical flocculation process above at the same coagulant dosage. The treatment process under different situations was evaluated on a pilot-scale experiment, and the results provided magnificent parameters and optimal condition for future operation of the plant.

  15. Biological assessment of contaminated land using earthworm biomarkers in support of chemical analysis

    International Nuclear Information System (INIS)

    Biological indicators can be used to assess polluted sites but their success depends on the availability of suitable assays. The aim of this study was to investigate the performance of two earthworm biomarkers, lysosomal membrane stability measured using the neutral red retention assay (NRR-T) and the total immune activity (TIA) assay, that have previously been established as responsive to chemical exposure. Responses of the two assays were measured following in situ exposure to complexly contaminated field soils at three industrial sites as well as urban and rural controls. The industrial sites were contaminated with a range of metal (cadmium, copper, lead, zinc, nickel and cobalt) and organic (including polycyclic aromatic hydrocarbons) contaminants, but at concentrations below the 'New Dutch List' Intervention concentrations. Exposed earthworms accumulated both metals and organic compounds at the contaminated sites, indicating that there was significant exposure. No effect on earthworm survival was found at any of the sites. Biomarker measurements, however, indicated significant effects, with lower NRR-T and TIA found in the contaminated soils when compared to the two controls. The results demonstrate that a comparison of soil pollutant concentrations with guideline values would not have unequivocally identified chemical exposure and toxic effect for soil organisms living in these soils. However, the earthworm biomarkers successfully identified significant exposure and biological effects caused by the mixture of chemicals present

  16. Computer program for calculation of complex chemical equilibrium compositions and applications. Part 1: Analysis

    Science.gov (United States)

    Gordon, Sanford; Mcbride, Bonnie J.

    1994-01-01

    This report presents the latest in a number of versions of chemical equilibrium and applications programs developed at the NASA Lewis Research Center over more than 40 years. These programs have changed over the years to include additional features and improved calculation techniques and to take advantage of constantly improving computer capabilities. The minimization-of-free-energy approach to chemical equilibrium calculations has been used in all versions of the program since 1967. The two principal purposes of this report are presented in two parts. The first purpose, which is accomplished here in part 1, is to present in detail a number of topics of general interest in complex equilibrium calculations. These topics include mathematical analyses and techniques for obtaining chemical equilibrium; formulas for obtaining thermodynamic and transport mixture properties and thermodynamic derivatives; criteria for inclusion of condensed phases; calculations at a triple point; inclusion of ionized species; and various applications, such as constant-pressure or constant-volume combustion, rocket performance based on either a finite- or infinite-chamber-area model, shock wave calculations, and Chapman-Jouguet detonations. The second purpose of this report, to facilitate the use of the computer code, is accomplished in part 2, entitled 'Users Manual and Program Description'. Various aspects of the computer code are discussed, and a number of examples are given to illustrate its versatility.

  17. X-Shooter GTO: Chemical analysis of a sample of EMP candidates

    CERN Document Server

    Caffau, E; François, P; Spite, M; Spite, F; Zaggia, S; Ludwig, H -G; Monaco, L; Sbordone, L; Cayrel, R; Hammer, F; Randich, S; Hill, V; Molaro, P

    2011-01-01

    Context: Extremely metal-poor stars (EMP) are very rare objects that hold in their atmospheres the fossil record of the chemical composition of the early phases of Galactic evolution. Finding these objects and determining their chemical composition provides important constraints on these early phases. Aims: Using a carefully designed selection method, we chose a sample of candidate EMP stars from the low resolution spectra of the Sloan Digital Sky Survey and observed them with X-Shooter at the VLT to confirm their metallicities and determine abundances for as many elements as possible. Method: The X-Shooter spectra are analysed by means of one-dimensional, plane-parallel, hydrostatic model atmospheres. Corrections for the granulation effects are computed using CO5BOLD hydrodynamical simulations. Results: All the candidates are confirmed to be EMP stars, proving the efficiency of our selection method within about 0.5 dex. The chemical composition of this sample is compatible with those of brighter samples, sug...

  18. Quantifying Chemical Reactions by using Mixing Analysis in Groundwater-River Interface

    Science.gov (United States)

    Jurado, A.; Vázquez-Suñé, E.; Carrera, J.; Tubau, I.; Pujades, E.

    2015-12-01

    This work is motivated by a sound understanding of the chemical processes that affect the organic pollutants in an urban aquifer. We propose an approach to quantify such processes using mixing calculations. The methodology consists of the following steps: (1) identification of the recharge sources (end-members) and selection of the species (conservative and non-conservative) to be used, (2) identification of the chemical processes and (3) evaluation of mixing ratios including the chemical processes. This methodology has been applied in the Besòs River Delta (NE Barcelona, Spain), where the River Besòs is the main aquifer recharge source. A total number of 51 groundwater samples were collected from July 2007 to May 2010 during four field campaigns. Three river end-members were necessary to explain the temporal variability of the River Besòs: one river end-member is from the wet periods (W1) and two are from dry periods (D1 and D2). This methodology has proved to be useful not only to compute the mixing ratios but also to quantify processes such as calcite and magnesite dissolution, aerobic respiration and denitrification undergone at each observation point

  19. Comparative Analysis of QSAR-based vs. Chemical Similarity Based Predictors of GPCRs Binding Affinity.

    Science.gov (United States)

    Luo, Man; Wang, Xiang S; Tropsha, Alexander

    2016-01-01

    Ligand based virtual screening (LBVS) approaches could be broadly divided into those relying on chemical similarity searches and those employing Quantitative Structure-Activity Relationship (QSAR) models. We have compared the predictive power of these approaches using some datasets of compounds tested against several G-Protein Coupled Receptors (GPCRs). The k-Nearest Neighbors (kNN) QSAR models were built for known ligands of each GPCR target independently, with a fraction of tested ligands for each target set aside as a validation set. The prediction accuracies of QSAR models for making active/inactive calls for compounds in both training and validation sets were compared to those achieved by the Prediction of Activity Spectra for Substances' (PASS) and the Similarity Ensemble Approach (SEA) tools both available online. Models developed with the kNN QSAR method showed the highest predictive power for almost all tested GPCR datasets. The PASS software, which incorporates multiple end-point specific QSAR models demonstrated a moderate predictive power, while SEA, a chemical similarity based approach, had the lowest prediction power. Our studies suggest that when sufficient amount of data is available to develop and rigorously validate QSAR models such models should be chosen as the preferred virtual screening tool in ligand-based computational drug discovery as compared to chemical similarity based approaches. PMID:27491652

  20. Advanced Exergy Analysis for Chemically Reacting Systems – Application to a Simple Open Gas-Turbine System

    Directory of Open Access Journals (Sweden)

    George Tsatsaronis

    2009-09-01

    Full Text Available

    A conventional exergy analysis has some limitations, which are significantly reduced by an advanced exergy analysis. The latter evaluates: (a the interactions among components of the overall system (splitting the exergy destruction into endogenous and exogenous parts; and, (b the real potential for improving a system component (splitting the exergy destruction into unavoidable and avoidable parts. The main role of an advanced exergy analysis is to provide engineers with additional information useful for improving the design and operation of energy conversion systems. This information cannot be supplied by any other approach. In previous publications, approaches were presented that were appropriate for application to closed thermodynamic cycles, without chemical reactions (e.g., refrigeration cycles. Here a general approach is discussed that could be applied to systems with chemical reactions. Application of this approach to a simple gas-turbine system reveals the potential for improvement and the interactions among the system components.

    • This paper is an updated version of a paper published in the ECOS'08 proceedings. 

  1. Study on the absorbed fingerprint-efficacy of yuanhu zhitong tablet based on chemical analysis, vasorelaxation evaluation and data mining.

    Directory of Open Access Journals (Sweden)

    Haiyu Xu

    Full Text Available Yuanhu Zhitong Tablet (YZT is an example of a typical and relatively simple clinical herb formula that is widely used in clinics. It is generally believed that YZT play a therapeutical effect in vivo by the synergism of multiple constituents. Thus, it is necessary to build the relationship between the absorbed fingerprints and bioactivity so as to ensure the quality, safety and efficacy. In this study, a new combinative method, an intestinal absorption test coupled with a vasorelaxation bioactivity experiment in vitro, was a simple, sensitive, and feasible technique to study on the absorbed fingerprint-efficacy of YZT based on chemical analysis, vasorelaxation evaluation and data mining. As part of this method, an everted intestinal sac method was performed to determine the intestinal absorption of YZT solutions. YZT were dissolved in solution (n = 12, and the portion of the solution that was absorbed into intestinal sacs was analyzed using rapid-resolution liquid chromatography coupled with quadruple time-of-flight mass spectrometry (RRLC-Q-TOF/MS. Semi-quantitative analysis indicated the presence of 34 compounds. The effect of the intestinally absorbed solution on vasorelaxation of rat aortic rings with endothelium attached was then evaluated in vitro. The results showed that samples grouped by HCA from chemical profiles have similar bioactivity while samples in different groups displayed very different. Moreover, it established a relationship between the absorbed fingerprints and their bioactivity to identify important components by grey relational analysis, which could predict bioactive values based on chemical profiles and provide an evidence for the quantification of multi-constituents.

  2. Development of accident frequency analysis S/W for chemical processes

    Energy Technology Data Exchange (ETDEWEB)

    Seo, Jae Min; Ko, Jae wook [College of Chemical Engineering, Kwangwoon University (Korea); Shin, Dong Il [School of Chemical Engineering, Seoul National University, Seoul (Korea)

    1999-12-01

    In this study, a computerized prototype program was developed with frequency analysis system as a main system and data base as sub-items to utilize data. Through use of gate-by-gate analysis and minimal cut set using boolean algebra, the frequency analysis program performed the qualitative approach for the accident development path and a quantitative risk analysis. In conclusion, it is thought that the resulting installation will be effective for lessening the probability of accidents through use of this lower cost software. 7 refs., 7 figs.

  3. Parameter identification and analysis of soluble chemical transfer from soil to surface runoff

    Directory of Open Access Journals (Sweden)

    J. X. Tong

    2012-03-01

    Full Text Available A two-layer mathematical model is used to predict the chemical transfer from the soil into the surface runoff with ponding water. There are two incomplete infiltration-related parameter γ and runoff-related parameter α in the analytical solution to the model, which were assumed to be constant in previous studies (Tong et al., 2010. In this study, experimental data are used to identify the variable γ and α based on the analytical solution. The soil depth of the mixing zone is kept to be constant in different experiments, and the values of γ and α before the surface runoff occurs are constant and equal to their values at the moment the runoff starts. From the study results, it is found that γ will decrease with the increase of the surface runoff time, the increase of the ponding-water depth, hp, or with the decrease of the initial volumetric water content. The variability of γ will decrease with the increase of the initial volumetric water content. Similarly, α will decrease with time for the initially unsaturated experimental soils, but will increase with time for the initially saturated experimental soils. The larger the infiltration, the less chemical concentration in the surface runoff is. The analytical solution is not valid for experimental soil without any infiltration if α is expected to be less or equal to 1. The results will help to quantify chemical transfer from soil into runoff, a significant problem in agricultural pollution management.

  4. Fish meal quality evaluated by chemical analysis and feed microscopy techniques

    Directory of Open Access Journals (Sweden)

    Anuchit Arthan

    2005-02-01

    Full Text Available Quality of 20 fishmeal samples from the Southern Provinces produced by different raw materials and processing method were evaluated using both chemical and feed microscopy methods. Samples were collected from fishmeal plants, shrimp feed mills and local feedstuff store. One sample using sardine as a raw material was produced in the laboratory by lyophilization as a control fishmeal. Five samples having protein contents over 65% were grouped into shrimp grade including the control fishmeal which had the maximum protein content of 74.09%. Eight samples were grouped into Grade 1 including the imported fishmeal from Chile. The rest of the samples which were mostly produced from trash fish fell into Grade 2 with low protein and high ash content. Chemical analyses of salt content, total volatile base nitrogen (TVN, ammonia nitrogen, histamine content, free fatty acid (FFA, thiobarbituric acid number (TBA and peroxide value showed the fishmeal from feedstuff store was the most deteriorated sample. This high level of deterioration might be due to low quality raw materials and a long storage time. Among the shrimp grade samples, the most denatured protein was found in Pattani 1 with high level of TVN, ammonia nitrogen and histamine. Moreover, the high levels of TVN were detected in Phangnga 1 (grade 1 and Trang 2 (grade 2. Lipid damage was associated with high fat contents in fish meal which was detected in every group of the samples. The results from feed microscopic examination were in line with those of the chemical analyses. The most deteriorated sample from feedstuff store showed the highest decomposition level and was the only sample that non protein nitrogen was detected. For feather meal adulteration test, seven samples were positive with the highest level in unidentified sample and trace amount in other samples including 2 shrimp grade samples. To confirm feather meal adulteration, protein digestibility test should be performed for these samples.

  5. Strategies for the chemical analysis of highly porous bone scaffolds using secondary ion mass spectrometry

    International Nuclear Information System (INIS)

    Understanding the distribution of critical elements (e.g. silicon and calcium) within silica-based bone scaffolds synthesized by different methods is central to the optimization of these materials. Time-of-flight secondary ion mass spectrometry (ToF-SIMS) has been used to determine this information due to its very high surface sensitivity and its ability to map all the elements and compounds in the periodic table with high spatial resolution. The SIMS image data can also be combined with depth profiles to construct three-dimensional chemical maps. However, the scaffolds have interconnected pore networks, which are very challenging structures for the SIMS technique. To overcome this problem two experimental methodologies have been developed. The first method involved the use of the focused ion beam technique to obtain clear images of the regions of interest and subsequently mark them by introducing fiducial marks; the samples were then analysed using the ToF-SIMS technique to yield the chemical analyses of the regions of interest. The second method involved impregnating the pores using a suitable reagent so that a flat surface could be achieved, and this was followed by secondary ion mapping and 3D chemical imaging with ToF-SIMS. The samples used in this work were sol–gel 70S30C foam and electrospun fibres and calcium-containing silica/gelatin hybrid scaffolds. The results demonstrate the feasibility of both these experimental methodologies and indicate that these methods can provide an opportunity to compare various artificial bone scaffolds, which will be of help in improving scaffold synthesis and processing routes. The techniques are also transferable to many other types of porous material. (paper)

  6. Analysis of Wetting and Contact Angle Hysteresis on Chemically Patterned Surfaces

    KAUST Repository

    Xu, Xianmin

    2011-01-01

    Wetting and contact angle hysteresis on chemically patterned surfaces in two dimensionsare analyzed from a stationary phase-field model for immiscible two phase fluids. We first study the sharp-interface limit of the model by the method of matched asymptotic expansions. We then justify the results rigorously by the γ-convergence theory for the related variational problem and study the properties of the limiting minimizers. The results also provide a clear geometric picture of the equilibrium configuration of the interface. This enables us to explicitly calculate the total surface energy for the two phase systems on chemically patterned surfaces with simple geometries, namely the two phase flow in a channel and the drop spreading. By considering the quasi-staticmotion of the interface described by the change of volume (or volume fraction), we can follow the change-of-energy landscape which also reveals the mechanism for the stick-slip motion of the interface and contact angle hysteresis on the chemically patterned surfaces. As the interface passes throughpatterned surfaces, we observe not only stick-slip of the interface and switching of the contact angles but also the hysteresis of contact point and contact angle. Furthermore, as the size of the patternde creases to zero, the stick-slip becomes weaker but the hysteresis becomes stronger in the sense that one observes either the advancing contact angle or the receding contact angle (when the interface ismoving in the opposite direction) without the switching in between. © 2011 Society for Industrial and Applied Mathematics.

  7. Quantitative and qualitative analysis of common peaks in chemical fingerprint of Yuanhu Zhitong tablet by HPLC-DAD–MS/MS

    OpenAIRE

    Dao-Quan Tang; Xiao-Xiao Zheng; Xu Chen; Dong-Zhi Yang; Qian Du

    2014-01-01

    A quality control (QC) strategy for quantitative and qualitative analysis of “common peaks” in chemical fingerprint was proposed to analyze Yuanhu Zhitong tablet (YZT), using high performance liquid chromatography with diode array detector and tandem mass spectrometry (HPLC-DAD–MS/MS). The chromatographic separation was achieved on an Agilent Eclipse plus C18 column with a gradient elution using a mixture of 0.4‰ ammonium acetate aqueous (pH 6.0 adjusted with glacial acetic acid) and acetonit...

  8. Analysis of nonequilibrium chemical processes in the plume of subsonic and supersonic aircraft with hydrogen and hydrocarbon combustion engine

    Energy Technology Data Exchange (ETDEWEB)

    Starik, A.M.; Lebedev, A.B.; Titova, N.S. [Central Inst. of Aviation Motors, Moscow (Russian Federation)

    1997-12-31

    On the basic of quasi one dimensional mixing model the numerical analysis of nonequilibrium chemical processes in the plume of subsonic and hypersonic aircraft is presented. It was found that species HNO, HNO{sub 3}, HNO{sub 4}, N{sub 2}O{sub 5}, ClO{sub 2}, CH{sub 3}NO{sub 2} could be formed as a result of nonequilibrium processes in the plume and their concentrations can essentially exceed both background values in free stream of atmosphere and their values at the nozzle exit plane. (author) 10 refs.

  9. Fundamentals of the Layer-by-Layer Chemical Analysis of Heterogeneous Samples Using Secondary Ion Energy-mass Spectrometry

    Science.gov (United States)

    Nikitenkov, Nikolay N.; Vilkhivskaya, Olga V.; Nikitenkov, Alexsey N.; Sypchenko, Vladimir S.

    The experimental results presented in this paper demonstrate an opportunity for phase analysisof the surfacelayers of heterogeneous solidsusing the energy spectra of secondary ions (ESSI). The resultant ESSI from performing layer-by-layersputteringof thin-film systems using a stationary N2+ primary ion beam are presented and discussed. As examples of such studies, the depth distributions of the chemical compositions were studied on ZnO/Zn andInxAsyOz/InAs. An analysis of the simultaneous change in depth of both secondary molecular ion intensities and secondary atomic ion energy distributions (with reference to the target) enables the identification of separate phases.

  10. SIMILARITY ANALYSIS OF DNA SEQUENCES BASED ON THE CHEMICAL PROPERTIES OF NUCLEOTIDE BASES, FREQUENCY AND POSITION OF GROUP MUTATIONS

    Directory of Open Access Journals (Sweden)

    Fatima KABLI

    2016-01-01

    Full Text Available The DNA sequences similarity analysis approaches have been based on the representation and the frequency of sequences components; however, the position inside sequence is important information for the sequence data. Whereas, insufficient information in sequences representations is important reason that causes poor similarity results. Based on three classifications of the DNA bases according to their chemical properties, the frequencies and average positions of group mutations have been grouped into two twelve-components vectors, the Euclidean distances among introduced vectors applied to compare the coding sequences of the first exon of beta globin gene of 11 species.

  11. Structural and chemical determination of the new nanolaminated carbide Mo2Ga2C from first principles and materials analysis

    International Nuclear Information System (INIS)

    Following our recent discovery of a new nanolaminated carbide, Mo2Ga2C, we herein present a detailed structural and chemical analysis of this phase based on ab initio calculations, X-ray photoelectron spectroscopy, high resolution scanning transmission electron microscopy, and neutron powder diffraction. Calculations suggest an energetically and dynamically stable structure for C in the octahedral sites between the Mo layers, with Ga bilayers – stacked in a simple hexagonal arrangement – between the Mo2C layers. The predicted elastic properties are below those of the related nanolaminate Mo2GaC. The predicted structure, including lattice parameters and atomic positions, is experimentally confirmed

  12. Employment of neural networks for analysis of chemical composition and cooling rate effect on CCT diagrams shape

    International Nuclear Information System (INIS)

    The paper presents possibility of employment of the original supercooled austenite transformation anisothermic diagrams forecasting method for analysis of the chemical composition effect on the CCT diagrams shape. The developed model makes it possible to substitute computer simulation for the costly and time consuming experiments. The information derived from calculations make it possible to plot diagrams illustrating the effects of the particular elements or pairs of elements, as well as cooling rate and/or austenitizing temperature, on any temperature or time describing transformations in steel during its continuous cooling. Evaluation is also possible of the effect of the aforementioned factors on hardness and fractions of the particular structural constituents. (author)

  13. Chemical Composition by Neutron Activation Analysis (INAA of Neo-Assyrian Palace Ware from Iraq, Syria and Israel

    Directory of Open Access Journals (Sweden)

    Alice M W Hunt

    2013-05-01

    Full Text Available Neo-Assyrian Palace Ware is an 8th-7th century B.C.E. fine-ware which originated in Northern Mesopotamia and spread throughout the greater Levant. The mechanism by which Palace Ware moved across the Neo-Assyrian imperial landscape (trade or local imitation/emulation is of great archaeological interest. This dataset provides chemical compositional data, generated using instrumental neutron activation analysis (INAA, for Palace Ware vessels from Nimrud and Nineveh, in the Assyrian imperial core (Iraq, Dūr-Katlimmu, in one of the annexed provinces (Syria, and Tell Jemmeh, located outside the Neo-Assyrian provincial system (Israel.

  14. UV Spectral Analysis of the Chemical Modification and Photolysis of Acetylacetone Modified Alumina Aqueous Solution

    Institute of Scientific and Technical Information of China (English)

    Chengbin JING; Xiujian ZHAO; Haizheng TAO; Xina WANG; Aiyun LIU

    2004-01-01

    Acetylacetone was firstly introduced into the aqueous media with the presence of aluminum sec-butoxide and peptizator. It was confirmed that the UV (ultraviolet) absorption band of acetylacetone underwent 14 nm of red-shift due to the formation of the six-membered ring of the complex between alumina and acetylacetone in the aqueous solution. It was also found that the chemical modification can be dissociated by the UV irradiation with a wavelength shorter than 286 nm as a result of the excitation of π-π* transition in the complex.

  15. WATER CHEMICAL ANALYSIS OF THE OXBOW LAKES NEAR THE UPPER-TISZA RIVER

    OpenAIRE

    BEÁTA BABKA; SZILÁRD SZABÓ

    2007-01-01

    The Tisza river plays an important role in the life of Eastern Hungary. Beside the river there are several oxbow lakes, cut off meanders. In this paper the water quality of these lakes was examined from the section of Tarpa to Rakamaz. 45 oxbow lakes were sampled and the chemical parameters were determined. Sodium was used as a pollutant (sewage water) indicator and 2 lakes were found extremelypolluted. The lakes outside the dam were slightly polluted because of the lack of renewal of the wat...

  16. Model analysis of the chemical conversion of exhaust species in the expanding plumes of subsonic aircraft

    Energy Technology Data Exchange (ETDEWEB)

    Moellhoff, M.; Hendricks, J.; Lippert, E.; Petry, H. [Koeln Univ. (Germany). Inst. fuer Geophysik und Meteorologie; Sausen, R. [Deutsche Forschungsanstalt fuer Luft- und Raumfahrt e.V. (DLR), Oberpfaffenhofen (Germany). Inst. fuer Physik der Atmosphaere

    1997-12-31

    A box model and two different one-dimensional models are used to investigate the chemical conversion of exhaust species in the dispersing plume of a subsonic aircraft flying at cruise altitude. The effect of varying daytime of release as well as the impact of changing dispersion time is studied with special respect to the aircraft induced O{sub 3} production. Effective emission amounts for consideration in mesoscale and global models are calculated. Simulations with modified photolysis rates are performed to show the sensitivity of the photochemistry to the occurrence of cirrus clouds. (author) 8 refs.

  17. Structural and chemical analysis of gadolinium halides encapsulated within WS2 nanotubes

    Science.gov (United States)

    Anumol, E. A.; Enyashin, Andrey N.; Batra, Nitin M.; Costa, Pedro M. F. J.; Deepak, Francis Leonard

    2016-06-01

    The hollow cavities of nanotubes serve as templates for the growth of size- and shape-confined functional nanostructures, giving rise to novel materials and properties. In this work, considering their potential application as MRI contrast agents, gadolinium halides are encapsulated within the hollow cavities of WS2 nanotubes by capillary filling to obtain GdX3@WS2 nanotubes (where X = Cl, Br or I and @ means encapsulated in). Aberration corrected scanning/transmission electron microscopy (S/TEM) and spectroscopy is employed to understand the morphology and composition of the GdI3@WS2 nanotubes. The three dimensional morphology is studied with STEM tomography but understanding the compositional information is non-trivial due to the presence of multiple high atomic number elements. Therefore, energy dispersive X-ray spectroscopy (EDS) tomography was employed revealing the three dimensional chemical composition. Molecular dynamics simulations of the filling procedure shed light into the mechanics behind the formation of the confined gadolinium halide crystals. The quasi-1D system employed here serves as an example of a TEM-based chemical nanotomography method that could be extended to other materials, including beam-sensitive soft materials.The hollow cavities of nanotubes serve as templates for the growth of size- and shape-confined functional nanostructures, giving rise to novel materials and properties. In this work, considering their potential application as MRI contrast agents, gadolinium halides are encapsulated within the hollow cavities of WS2 nanotubes by capillary filling to obtain GdX3@WS2 nanotubes (where X = Cl, Br or I and @ means encapsulated in). Aberration corrected scanning/transmission electron microscopy (S/TEM) and spectroscopy is employed to understand the morphology and composition of the GdI3@WS2 nanotubes. The three dimensional morphology is studied with STEM tomography but understanding the compositional information is non-trivial due to the

  18. Analysis of chemical components of shiitake polysaccharides and its anti-fatigue effect under vibration.

    Science.gov (United States)

    Li, Xiaoling; Zhang, Hongbo; Xu, Haibo

    2009-11-01

    The shiitake polysaccharides were obtained from shiitake mushroom. Four fractions were isolated from the polysaccharides using a Sephadex G-100 gel column. Chemical components of the two main fractions were determined by thin layer chromatography (TLC), and high performance liquid chromatography (HPLC). F1 was composed of rhamnose, glucose, and mannose. F3 was composed of xylose, mannose, arabinose and galactose. The obtained results still showed that administration of shiitake polysaccharides could improve muscle's comfortability of animals under a long period of vibration. The above findings might be applicable to studies of vibration ergonomics. PMID:19643126

  19. Qualitative analysis of the chemical constituents in Hedyotis diffusa by HPLC-TOF-MS.

    Science.gov (United States)

    Wang, Xu; Cheng, Weiming; Yao, Xinning; Guo, Xingjie

    2012-01-01

    A high performance liquid chromatography-time-of-flight-mass spectrometry (HPLC-TOF-MS) method was developed for analysing the chemical constituents in Hedyotis diffusa, which is widely used as a traditional Chinese medicine (TCM) in the field of cancer treatment. The compounds were identified either by comparing the retention time and mass spectrometry data with those of reference compounds or by analysing mass spectrometry data and retrieving reference literature. Among the detected chromatographic peaks, nine components were unambiguously identified, most of which were iridoids. This study is expected to provide an effective and reliable pattern for comprehensive and systematic characterisation of the complex TCM systems. PMID:21838590

  20. Study on the methods for analysis of the chemical poison in canister by neutron activity

    International Nuclear Information System (INIS)

    The method that is used to analyse the poison gases in canister by neutron activity is proposed. Through theory analysis and experimental measurement, the feasibility for analysis of the poison gases in a canister by neutron activity has been demonstrated, and it is proved that the method itself do not result in radioactive problem to use again the canister. (authors)