WorldWideScience

Sample records for chemical composition

  1. Computing Equilibrium Chemical Compositions

    Science.gov (United States)

    Mcbride, Bonnie J.; Gordon, Sanford

    1995-01-01

    Chemical Equilibrium With Transport Properties, 1993 (CET93) computer program provides data on chemical-equilibrium compositions. Aids calculation of thermodynamic properties of chemical systems. Information essential in design and analysis of such equipment as compressors, turbines, nozzles, engines, shock tubes, heat exchangers, and chemical-processing equipment. CET93/PC is version of CET93 specifically designed to run within 640K memory limit of MS-DOS operating system. CET93/PC written in FORTRAN.

  2. The Chemical Composition of Honey

    Science.gov (United States)

    Ball, David W.

    2007-01-01

    Honey is a supersaturated sugar solution, created by bees, and used by human beings as a sweetener. However, honey is more than just a supersaturated sugar solution; it also contains acids, minerals, vitamins, and amino acids in varying quantities. In this article, we will briefly explore the chemical composition of honey. (Contains 2 figures and…

  3. Graphene composites containing chemically bonded metal oxides

    Indian Academy of Sciences (India)

    K Pramoda; S Suresh; H S S Ramakrishna Matte; A Govindaraj

    2013-08-01

    Composites of graphene involving chemically bonded nano films of metal oxides have been prepared by reacting graphene containing surface oxygen functionalities with metal halide vapours followed by exposure to water vapour. The composites have been characterized by electron microscopy, atomic force microscopy and other techniques. Magnetite particles chemically bonded to graphene dispersible in various solvents have been prepared and they exhibit fairly high magnetization.

  4. The Chemical Composition of Maple Syrup

    Science.gov (United States)

    Ball, David W.

    2007-01-01

    Maple syrup is one of several high-sugar liquids that humans consume. However, maple syrup is more than just a concentrated sugar solution. Here, we review the chemical composition of maple syrup. (Contains 4 tables and 1 figure.)

  5. Chemical Composition of Essential Oil from Akway

    OpenAIRE

    Meike Meilan Lisangan; Bimo Budi Santoso; Gino Nemesio Cepeda; Isak Silamba

    2011-01-01

    Chemical Composition of Essential Oil from Akway. Akway (Drimys piperita Hook f.) is a woody, evergreen andaromatic plan that was a member of winteraceae. This plant is used by Sougb tribe lived in Sururey village, District ofManokwari, to heal malaria and to enhance the vitality of body. The objectives of this research were to know the yieldof essential oil using water distillation of leaves and its chemical composition using gas chromatography and massspectroscopy (GC-MS). The results indic...

  6. Chemical composition of Earth-like planets

    CERN Document Server

    Ronco, M P; Marboeuf, U; Alibert, Y; de Elía, G C; Guilera, O M

    2015-01-01

    Models of planet formation are mainly focused on the accretion and dynamical processes of the planets, neglecting their chemical composition. In this work, we calculate the condensation sequence of the different chemical elements for a low-mass protoplanetary disk around a solar-type star. We incorporate this sequence of chemical elements (refractory and volatile elements) in our semi-analytical model of planet formation which calculates the formation of a planetary system during its gaseous phase. The results of the semi-analytical model (final distributions of embryos and planetesimals) are used as initial conditions to develope N-body simulations that compute the post-oligarchic formation of terrestrial-type planets. The results of our simulations show that the chemical composition of the planets that remain in the habitable zone has similar characteristics to the chemical composition of the Earth. However, exist differences that can be associated to the dynamical environment in which they were formed.

  7. Chemical composition of Earth-like planets

    OpenAIRE

    Ronco, M. P.; Thiabaud, A.; Marboeuf, U.; Alibert, Y.; de Elía, G. C.; O. M. Guilera

    2015-01-01

    Models of planet formation are mainly focused on the accretion and dynamical processes of the planets, neglecting their chemical composition. In this work, we calculate the condensation sequence of the different chemical elements for a low-mass protoplanetary disk around a solar-type star. We incorporate this sequence of chemical elements (refractory and volatile elements) in our semi-analytical model of planet formation which calculates the formation of a planetary system during its gaseous ...

  8. Chemical composition of selected Saudi medicinal plants

    Directory of Open Access Journals (Sweden)

    Ihsanullah Daur

    2015-05-01

    Full Text Available Medicinal plants are important in traditional medicine and modern pharmaceutical drugs; therefore, the interest in the analysis of their chemical composition is increasing. In this study, selected medicinal plants including Achillea fragrantissima (Forssk Sch., Amaranthus viridis L., Asteriscus graveolens (Forssk. Less., Chenopodium album L., and Conyza bonariensis (L. Cronquist were collected from the rangeland of western regions (Bahra and Hada areas of Saudi Arabia to study their chemical composition. Eight minerals (Mg, Ca, Cr, Mn, Fe, Co, Cu, and Zn, total phenolic contents, antioxidant activity, and free-radical scavenging ability were examined in order to evaluate the medicinal potential of these plants. All the plants were found to be rich sources of minerals and antioxidants, although there were significant differences (p < 0.05 in their chemical composition, which may provide a rationale for generating custom extracts from specific plants depending on the application. The findings of this study will thus facilitate herbalists in their efforts to incorporate these plants into various formulations based on their chemical composition.

  9. Chemical Composition of Essential Oil from Akway

    Directory of Open Access Journals (Sweden)

    Meike Meilan Lisangan

    2011-04-01

    Full Text Available Chemical Composition of Essential Oil from Akway. Akway (Drimys piperita Hook f. is a woody, evergreen andaromatic plan that was a member of winteraceae. This plant is used by Sougb tribe lived in Sururey village, District ofManokwari, to heal malaria and to enhance the vitality of body. The objectives of this research were to know the yieldof essential oil using water distillation of leaves and its chemical composition using gas chromatography and massspectroscopy (GC-MS. The results indicated that the yield of leaves essential oil by using water distillation was 0.2%.The essential oil composed by 49 compounds categorized by terpene and its derivatives 83.67%, derivatives of benzene4.08% and alifatic compounds 8.16%.

  10. Chemical Composition and Antibacterial Effects of

    OpenAIRE

    SS Saei Dehkordi; H Tajik; Moradi, M; A Jafari Dehkordi; Ghasemi, S.

    2009-01-01

    Introduction & Objective: Rosmarinus officinalis L. as a member of the Lamiaceae family and lysozyme as a natural antibacterial agent is important in food microbiology, because of its characteristics. The aim of the present study was to determine the chemical composition and anti-listerial activity of Rosmarinus officinalis essential oil (REO) alone and in combination with lysozyme for enhancement of anti-listerial activity of both substances. Materials & Methods: Rosmarinus officinalis ...

  11. Impact of oil on groundwater chemical composition

    Science.gov (United States)

    Brakorenko, N. N.

    2015-11-01

    The objective of the paper is to characterize the chemical composition of groundwater samples from the monitoring wells drilled in the petrol station areas within the vicinity of Tomsk. The level of contamination has increased since many macro - and microcomponent concentrations (such as petroleum products, chlorine, sulphates, carbon dioxide and lead, etc.) in groundwater samples of the present study is higher than that in previous period samples.

  12. Ostrich – yield and chemical composition

    OpenAIRE

    Naseva, Dijana; Pejkovski, Zlatko; Kuzelov, Aco

    2012-01-01

    Faced with the fact that the world’s population is increasing year over year and that it is faced with the lack of food, especially meat, the alimentary technology should necessarily consider each alimentary source. This thesis studies the quality and quantity of ostriches' meat. The results of the live weight, slaughter weight, dressing percentage and losses of weight under chilling, the content of meat and bones in the main parts (thighs, back, thorax) and the chemical composition of the ...

  13. Cometary Coma Chemical Composition (C4) Mission

    Science.gov (United States)

    Carle, Glenn C.; Clark, Benton C.; Knocke, Philip C.; OHara, Bonnie J.; Adams, Larry; Niemann, Hasso B.; Alexander, Merle; Veverka, Joseph; Goldstein, Raymond; Huebner, Walter; Morrison, David (Technical Monitor)

    1994-01-01

    Cometary exploration remains of great importance to virtually all of space science. Because comets are presumed to be remnants of the early solar nebula, they are expected to provide fundamental knowledge as to the origin and development of the solar system as well as to be key to understanding of the source of volatiles and even life itself in the inner solar system. Clearly the time for a detailed study of the composition of these apparent messages from the past has come. A comet rendezvous mission, the Cometary Coma Chemical Composition (C4) Mission, is now being studied as a candidate for the new Discovery program. This mission is a highly-focussed and usefully-limited subset of the Cometary Rendezvous Asteroid Flyby (CRAF) Mission. The C4 mission will concentrate on measurements that will produce an understanding of the composition and physical makeup of a cometary nucleus. The core science goals of the C4 mission are 1) to determine the chemical, elemental, and isotopic composition of a cometary nucleus and 2) to characterize the chemical and isotopic nature of its atmosphere. A related goal is to obtain temporal information about the development of the cometary coma as a function of time and orbital position. The four short-period comets -- Tempel 1, Tempel 2, Churyumov-Gerasimenko, and Wirtanen -which all appear to have acceptable dust production rates, were identified as candidate targets. Mission opportunities have been identified beginning as early as 1998. Tempel I with a launch in 1999, however, remains the baseline comet for studies of and planning the C4 mission. The C4 mission incorporates two science instruments and two engineering instruments in the payload to obtain the desired measurements. The science instruments include an advanced version of the Cometary Ice and Dust Experiment (CIDEX), a mini-CIDEX with a sample collection system, an X-ray Fluorescence Spectrometer and a Pyrolysis-Gas Chromatograph, and a simplified version of the Neutral

  14. The Chemical Composition of Grape Fibre

    Directory of Open Access Journals (Sweden)

    Jolana Karovičová

    2015-05-01

    Full Text Available Dietary fibres from cereals are much more used than dietary fibres from fruits; however, dietary fibres from fruits have better quality. In recent years, for economic and environmental reasons, there has been a growing pressure to recover and exploit food wastes. Grape fibre is used to fortify baked goods, because the fibre can lower blood sugar, cut cholesterol and may even prevent colon cancer. Grape pomace is a functional ingredient in bakery goods to increase total phenolic content and dietary fibre in nourishment. The aim of this study was to determine the chemical composition of commercial fibres, obtained from different Grape sources concerning their chemical properties such as moisture, ash, fat, protein, total dietary fibre. The chemical composition of Grape fibre is known to vary depending on the Grape cultivar, growth climates, and processing conditions. The obliged characteristics of the fibre product are: total dietary fibre content above 50%, moisture lower than 9%, low content of lipids, a low energy value and neutral flavour and taste. Grape pomace represents a rich source of various high-value products such as ethanol, tartrates and malates, citric acid, Grape seed oil, hydrocolloids and dietary fibre. Used commercial Grape fibres have as a main characteristic, the high content of total dietary fibre. Amount of total dietary fibre depends on the variety of Grapes. Total dietary fibre content (TDF in our samples of Grape fibre varied from 56.8% to 83.6%. There were also determined low contents of moisture (below 9%. In the samples of Grape fibre were determined higher amount of protein (8.6 - 10.8%, mineral (1.3 - 3.8% and fat (2.8 - 8.6%. This fact opens the possibility of using both initial by-products as ingredients in the food industry, due to the effects associated with the high total dietary fibre content.

  15. Chemical composition of water extracts from shungite and shungite water

    International Nuclear Information System (INIS)

    Chemical analysis of water extracts from shungite-3 of Zagozhino deposit (Karelia) and natural water contacting with shungite rocks are done. Chemical composition and bactericide properties of shungite water are studied

  16. EFFECT OF CHEMICAL COMPOSITION ON RETAINED AUSTENITE IN TRIP STEEL

    Institute of Scientific and Technical Information of China (English)

    Y. Chen; X. Chen; Q.F. Wang; G.L. Yuan; C.Y. Li; X.Y. Li; Y.X. Wang

    2002-01-01

    The systematic chemical compositions including common C, Si, Mn, Al, and micro- alloying elements of Ti and Nb were designed for high volume fraction of retained austenite as much as possible. The thermo-cycle experiments were conducted by using Gleeble 2000 thermo-dynamic test machine for finding the appropriate composition. The experimental results showed that chemical composition had a significant effect on retained austenite, and the appropriate compositions were determined for commercial production of TRIP steels.

  17. Chemical Composition and Antibacterial Effects of

    Directory of Open Access Journals (Sweden)

    SS Saei Dehkordi

    2009-10-01

    Full Text Available Introduction & Objective: Rosmarinus officinalis L. as a member of the Lamiaceae family and lysozyme as a natural antibacterial agent is important in food microbiology, because of its characteristics. The aim of the present study was to determine the chemical composition and anti-listerial activity of Rosmarinus officinalis essential oil (REO alone and in combination with lysozyme for enhancement of anti-listerial activity of both substances. Materials & Methods: Rosmarinus officinalis L. was purchased from a local grocery store at Shahrekord and was identified by the Institute of Medicinal Plants, ACECR. The air-dried aerial parts were subjected to hydrodistillation using a Clevenger apparatus to obtain essential oil and yielded oil was analyzed by GC/MS. Antibacterial activity (on basis of Minimum Inhibitory Concentration (MIC of REO was studied separately and in combination with unheated lysozyme (L and heat-treated lysozyme (HTL on Listeria monocytogenes at different pH (5, 6 and 7 by a micro-broth dilution assay. The collected data were analyzed by SPSS software. Results: In the current study, 98.05% of constituents of the essential oil were identified. The major components were α-pinene (14.06%, 1,8-cineole (13.62%, verbenone (11.2%, camphor (10.51%, borneol (7.3%, 3-octanone (7.02%, camphene (5.46% and linalool (5.07%. The inhibitory action of REO was stronger at lower pH especially 5 (MIC=225 μg/mL. Inhibition by L at pH 5 was 640 μg/mL but no inhibition was seen at pH 7. HTL resulted in more effective inhibition than L, especially at pH 5 and heat-treatment 80˚C (MIC: 160 μg/mL. Conclusion: Combination of L + REO and particularly HTL + REO was led to enhancement of bacterial inhibition. It was concluded that REO by the identified chemical composition was effective alone or in combination with L or HTL on Listeria monocytogenes as a food-borne pathogen.

  18. On-line chemical composition analyzer development

    Energy Technology Data Exchange (ETDEWEB)

    Roberts, M.J.; Garrison, A.A.; Muly, E.C.; Moore, C.F.

    1992-02-01

    The energy consumed in distillation processes in the United States represents nearly three percent of the total national energy consumption. If effective control of distillation columns can be accomplished, it has been estimated that it would result in a reduction in the national energy consumption of 0.3%. Real-time control based on mixture composition could achieve these savings. However, the major distillation processes represent diverse applications and at present there does not exist a proven on-line chemical composition sensor technology which can be used to control these diverse processes in real-time. This report presents a summary of the findings of the second phase of a three phase effort undertaken to develop an on-line real-time measurement and control system utilizing Raman spectroscopy. A prototype instrument system has been constructed utilizing a Perkin Elmer 1700 Spectrometer, a diode pumped YAG laser, two three axis positioning systems, a process sample cell land a personal computer. This system has been successfully tested using industrially supplied process samples to establish its performance. Also, continued application development was undertaken during this Phase of the program using both the spontaneous Raman and Surface-enhanced Raman modes of operation. The study was performed for the US Department of Energy, Office of Industrial Technologies, whose mission is to conduct cost-shared R D for new high-risk, high-payoff industrial energy conservation technologies. Although this document contains references to individual manufacturers and their products, the opinions expressed on the products reported do not necessarily reflect the position of the Department of Energy.

  19. Chemical composition of rainwater in Eastern France

    Science.gov (United States)

    Sanusi, Astrid; Wortham, Henri; Millet, Maurice; Mirabel, Philippe

    Rainwater sampled weekly at nine sites in eastern France from October 1991 to March 1992 has been analysed for major ions (Cl -, NO 3-, SO s2-, NH 4+, Na +, K +, Mg 2+ and Ca 2+), pH and conductivity. The major elements are SO 42- and Cl - for the anions and NH 4+ and Ca 2+ for the cations. The major ion concentrations are higher in urban areas, especially at Colmar (no.2), where rainfall amounts are low. Surprisingly, the acidity is higher at the sites in rural areas [i.e. mean pH of 4.4 for Ban sur Meurthe (no. 7)] and lower in the urban areas [mean pH of 5.0 for Strasbourg (no. 1) and pH of 5.7 for Colmar (no. 2)]. This is probably due to the presence of CaCO 3 in the "loess", which is the major constituent of soils in the upper Rhine valley. The relationship between the chemical composition of rain andair-mass trajectories for four humid weeks which presented only one rain event are also examined.

  20. Chemical compositions of four barium stars

    CERN Document Server

    Liang, Y C; Chen, Y Q; Qiu, H M; Zhang, B

    2003-01-01

    Chemical compositions of four barium stars HD 26886, HD 27271, HD 50082 and HD 98839 are studied based on high resolution, high signal-to-noise Echelle spectra. Results show that all of them are disk stars. Their \\alpha and iron peak elements are similar to the solar abundances. The neutron-capture process elements are overabundant relative to the Solar. The heavy-element abundances of the strong Ba star HD 50082 are higher than those of other three mild Ba stars. Its mass is 1.32Msun (+0.28,-0.22Msun), and is consistent with the average mass of strong Ba stars (1.5Msun). For mild Ba star HD 27271 and HD 26886, the derived masses are 1.90Msun (+0.25,-0.20Msun) and 2.78Msun (+0.75,-0.78M_sun), respectively, which are consistent with the average mass of mild Ba stars. We also calculate the theoretical abundances of Ba stars by combining the AGB stars nucleosynthesis and wind accretion formation scenario of Ba binary systems. The comparisons between the observed abundance patterns of the sample stars with the th...

  1. Measurement of cosmic ray chemical composition at Mt. Chacaltaya

    International Nuclear Information System (INIS)

    BASJE group has measured the chemical composition of primary cosmic rays with energies around the knee with several methods. These measurements show that the averaged mass number of cosmic ray particles increases with energy up to the knee. In order to measure the chemical composition in much wider energy range, it was started a new experiment at Mt. Chacaltaya in 2000

  2. Chemical composition and in sacco digestibility of some Tunisian roughages

    OpenAIRE

    Moncef Hammami; Rachid Bouraoui; Hamadi Rouissi

    2011-01-01

    The present study aims at measuring the chemical composition and the ruminal degradability of some Tunisian roughage. The roughages were analysed to determine their chemical composition. Ruminal degradability of the roughages was determined using the technique of nylon bags. There were significant differences (P

  3. Compositional, physical and chemical modification of polylactide

    Directory of Open Access Journals (Sweden)

    M. Żenkiewicz

    2010-11-01

    Full Text Available Purpose: The purpose of this article was to review some of the modification methods applied to improve mechanical, barrier and/or surface properties of polylactide (PLA.Design/methodology/approach: The presented modification methods were classified into three groups due to the dominant role of compositional, physical or chemical factor effecting the most PLA properties.Findings: It was found that incorporation of small amounts of montmorillonite up to 5% leads to formation of a nanocomposite with enhanced tensile strength and improved barrier properties. Corona treatment of pure PLA and PLA contained MMT nanofiller causes a significant decrease in the water contact angle and does not essentially affect the diiodomethane contact angle. This treatment leads to an increase in surface free energy that is much more significant for pure PLA than for PLA containing MMT nanofiller. It was also found that with increasing number up to 1000 of laser pulses of energies 5 mJ/cm2 an increase in surface free energy was observed, while the next laser pulses caused decrease of this energy. The determination and comparison of the influence of 3 wt.% of trimethylopropane trimethacylate (TMPTA and 3 wt.% of trially isocyanurate (TAIC crosslinking agents on the thermomechanical properties of electron beam irradiated PLA was reported.Research limitations/implications: A number of various modification methods are widely reported in literature. In this article a review of only such modification methods is presented, which are in line with the newest trends in polymer industry and science.Practical implications: There are a number of PLA properties, which need to be improved to satisfy specific application conditions. For that reasons researches are leading to find suitable modification methods to improve selected properties of PLA.Originality/value: This article presents some of modification methods, which are in line with the newest trends in polymer industry and

  4. THE STUDY OF CHEMICAL COMPOSITION FOR ANIMAL FATS DURING STORAGE

    OpenAIRE

    Flavia Pop; Cornel Laslo

    2009-01-01

    In this article the chemical composition for 3 types of animal fats (pork fat, beef tallow and buffalo tallow), following the variation of saturated and unsaturated fatty acids proportion during freezing storage was studied. Determination of chemical composition of animal fats is important in establishing organoleptic and physico-chemical parameters, the variation of them in time, nature and proportion of fatty acids conferring specific characteristics to them. For pork fat was determined the...

  5. Characteristics and chemical compositions of propolis from Ethiopia

    OpenAIRE

    Rushdi, Ahmed I.; Adgaba, Nuru; Bayaqoob, Noofal I M; Al-Khazim, Ahmed; Simoneit, Bernd I T; El-Mubarak, Aarif H.; Al-Mutlaq, Khalid F

    2014-01-01

    Introduction Propolis is a sticky material mixed by honeybees to utilize it in protecting their hives from infection by bacteria and fungi. The therapeutic properties of propolis are due to its chemical composition with bio-active compounds; therefore, researchers are interested in studying its chemical constituents and biological properties. The main objective of this study is to determine the chemical compositions, characteristics and relative concentrations of organic compounds in the extr...

  6. Sensory properties and chemical composition of Sharri cheese from Kosovo

    OpenAIRE

    Agim Rysha; Frane Delaš

    2014-01-01

    Food sensory properties, analyses and chemical composition are very important because they provide information about product quality and end-user acceptance or preferences. An assessment of sensory characteristics and chemical composition of mountain sheep and cow’s-milk cheese from shepherd’s huts and industrial manufacturers in Kosovo was carried out. Consumer-oriented tests using a 9 point hedonic scale were conducted in order to determine Sharri cheese acceptability. Chemical parameters (...

  7. Chemical composition and in sacco digestibility of some Tunisian roughages

    Directory of Open Access Journals (Sweden)

    Moncef Hammami,

    2011-08-01

    Full Text Available The present study aims at measuring the chemical composition and the ruminal degradability of some Tunisian roughage. The roughages were analysed to determine their chemical composition. Ruminal degradability of the roughages was determined using the technique of nylon bags. There were significant differences (P<0.05 among roughages with regard to immediately soluble fraction, insoluble but degradable fraction, and fraction rate of degradation.

  8. Essential Oils, Part III: Chemical Composition.

    Science.gov (United States)

    de Groot, Anton C; Schmidt, Erich

    2016-01-01

    Data on the chemistry of essential oils which have caused contact allergy are provided. The largest group of chemicals found in essential oils consists of terpenes. The number of identified components usually ranges from 100 to 250, but in some oils (lavender, geranium, rosemary) 450 to 500 chemicals have been found. Many chemicals are present in a large number of oils, up to 98% for β-caryophyllene and 97% for limonene. Chemicals that are important constituents of >20 oils are limonene, linalool, and α-pinene. In many essential oils, there are 2 to 5 components which together constitute over 50% to 60% of the oil. In some oils, however, there is one dominant ingredient, making up more than 50% of the oil, including (E)-anethole in aniseed and star anise oil, carvone in spearmint oil, 1,8-cineole (eucalyptol) in Eucalyptus globulus oil, and (E)-cinnamaldehyde in cassia oil. The most important chemicals in 93 individual oils are specified. PMID:27427817

  9. Chemical composition of Earth, Venus, and Mercury

    OpenAIRE

    Morgan, John W.; Anders, Edward

    1980-01-01

    Model compositions of Earth, Venus, and Mercury are calculated from the premise that planets and chondrites underwent four identical fractionation processes in the solar nebula. Because elements of similar properties stay together in these processes, five constraints suffice to define the composition of a planet: mass of the core, abundance of U, and the ratios K/U, Tl/U, and FeO/(FeO + MgO). Complete abundance tables, and normative mineralogies, are given for all three planets. Review of ava...

  10. Honey: Chemical composition, stability and authenticity.

    Science.gov (United States)

    da Silva, Priscila Missio; Gauche, Cony; Gonzaga, Luciano Valdemiro; Costa, Ana Carolina Oliveira; Fett, Roseane

    2016-04-01

    The aim of this review is to describe the chemical characteristics of compounds present in honey, their stability when heated or stored for long periods of time and the parameters of identity and quality. Therefore, the chemical characteristics of these compounds were examined, such as sugars, proteins, amino acids, enzymes, organic acids, vitamins, minerals, phenolic and volatile compounds present in honey. The stability of these compounds in relation to the chemical reactions that occur by heating or prolonged storage were also discussed, with increased understanding of the behavior regarding the common processing of honey that may compromise its quality. In addition, the identity and quality standards were described, such as sugars, moisture, acidity, ash and electrical conductivity, color, 5-HMF and diastase activity, along with the minimum and maximum limits established by the Codex Alimentarius. PMID:26593496

  11. Features of a chemical composition of dry leaves of Steviavebaudiana

    OpenAIRE

    Irina Borisovna Krasina; Natalia AleksandrovnaTarasenko

    2016-01-01

    This work is dedicated to the study of a chemical composition of dry leaves of Stevia. Dry leaves of Stevia contain diterpene glycosides that contribute to their sweet taste, which makes possible the use of Stevia as a sugar substitute in a production of flour confectionery products. The evaluation of amino acid composition of dried leaves of Stevia showed that their composition includes 7 essential amino acids, among them the limiting amino acid is valine.During experimental researches it wa...

  12. The chemical composition of the Galileian satellites

    CERN Document Server

    Celebonovic, V

    1998-01-01

    Using the semiclassical theory of dense matter proposed by P.Savic and R.Kasanin,the mean molecular masses of the Galilean satellites of Jupiter are determined.The calculated values are fitted by plausible combinations of chemical elements,and the results are in good agreement with the observations by "Galileo".Possible cosmogonical explanations are briefly discussed.

  13. A new material for chemical industry - wood polymer composites

    International Nuclear Information System (INIS)

    The paper outlines the advantages of the radiation cured wood-polymer composites (WPC) for application in certain critical areas of chemical industry. The wood-polymer composite made filterpress frames and plates were tested in a chemical plant. The entire exercise is elaborated. The radiation cured wood exhibited a considerably extended useful life in alkaline and acidic solutions. Composites based on teak wood showed a remarkable improvement with a nominal polymer loading of 10%. The reports of accelerated aging test of WPC are also presented. (auth.)

  14. Chemical composition of earth, Venus, and Mercury

    Science.gov (United States)

    Morgan, J. W.; Anders, E.

    1980-01-01

    Model compositions of the earth, Venus, and Mercury are calculated from the premise that planets and chondrites underwent four identical fractionation processes in the solar nebula. Because elements of similar properties stay together in these processes, five constraints suffice to define the composition of a planet: mass of the core, abundance of U, and the ratios K/U, TI/U, and FeO/(FeO + MgO). Complete abundance tables, and normative mineralogies, are given for all three planets. A review of available data shows only a few gross trends for the inner planets: FeO decreases with heliocentric distance, whereas volatiles are depleted and refractories are enriched in the smaller planets.

  15. Genus Mikania: chemical composition and phytotherapeutical activity

    Directory of Open Access Journals (Sweden)

    Luciane C. Rufatto

    2012-12-01

    Full Text Available The genus Mikania ranks high in the list of best-selling natural products in the world. Its main distribution is in South America, but some species are found in Asia, North America and Africa. It is used for treating fever, rheumatism, colds and respiratory diseases, as well as snake bites and scorpion stings, due to its broad spectrum of action. There are approximately 430 species of this genus and only 12% have been studied, highlighting their chemical and pharmacological diversity. The main chemical groups are: coumarins and derivatives, sesquiterpenes, sesquiterpenes lactones, diterpenes, phytosterols/terpenoids and flavonoids. This review aims to supply useful references for scientists interested in natural products and the search for new compounds, from over the 300 already described for the genus.

  16. 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.

  17. Chemical composition of Hanford Tank SY-102

    International Nuclear Information System (INIS)

    The US Department of Energy established the Tank Waste Remediation System (TWRS) to safely manage and dispose of the radioactive waste, both current and future, stored in double-shell and single-shell tanks at the Hanford sites. One major program element in TWRS is pretreatment which was established to process the waste prior to disposal using the Hanford Waste Vitrification Plant. In support of this program, Los Alamos National Laboratory has developed a conceptual process flow sheet which will remediate the entire contents of a selected double-shelled underground waste tank, including supernatant and sludge, into forms that allow storage and final disposal in a safe, cost-effective and environmentally sound manner. The specific tank selected for remediation is 241-SY-102 located in the 200 West Area. As part of the flow sheet development effort, the composition of the tank was defined and documented. This database was built by examining the history of liquid waste transfers to the tank and by performing careful analysis of all of the analytical data that have been gathered during the tank's lifetime. In order to more completely understand the variances in analytical results, material and charge balances were done to help define the chemistry of the various components in the tank. This methodology of defining the tank composition and the final results are documented in this report

  18. The Chemical Composition of Praesepe (M44)

    CERN Document Server

    Boesgaard, Ann Merchant; Lum, Michael G

    2013-01-01

    Star clusters have long been used to illuminate both stellar evolution and Galactic evolution. They also hold clues to the chemical and nucleosynthetic processes throughout the history of the Galaxy. We have taken high signal-to-noise, high-resolution spectra of 11 solar-type stars in the Praesepe open cluster to determine the chemical abundances of 16 elements: Li, C, O, Na, Mg, Al, Si, Ca, Sc, Ti, V, Cr, Fe, Ni, Y, and Ba. We have determined Fe from Fe I and Fe II lines and find [Fe/H] = +0.12 $\\pm$0.04. We find that Li decreases with temperature due to increasing Li depletion in cooler stars; it matches the Li-temperature pattern found in the Hyades. The [C/Fe] and [O/Fe] abundances are below solar and lower than the field star samples due to the younger age of Praesepe (0.7 Gyr) than the field stars. The alpha-elements, Mg, Si, Ca, and Ti, have solar ratios with respect to Fe, and are also lower than the field star samples. The Fe-peak elements, Cr and Ni, track Fe and have solar values. The neutron captu...

  19. Cometary coma chemical composition (C4) mission. [Abstract only

    Science.gov (United States)

    Carle, G. C.; Clark, B. C.; Niemann, H. B.; Alexander, M.; Knocke, P. C.; O'Hara, B. J.

    1994-01-01

    Cometary missions are of enormous fundamental importance for many different space science disciplines, including exobiology. Comets are presumed relics of the earliest, most primitive material in the solar nebula and are related to the planetesimals. They undoubtedly provided a general enrichment of volatiles to the inner solar system (contributing to atmospheres and oceans) and may have been key to the origin of life. A Discovery class, comet rendezvous mission, the Cometary Coma Chemical Composition (C4) Mission, was selected for further study by NASA earlier this year. The C4 Mission is a highly focused and usefully-limited subset of the Cometary Rendezvous Asteroid Flyby (CRAF) Mission, concentrating exclusively on measurements which will lead to an understanding of the chemical composition and make-up of the cometary nucleus. The scientific goals of the Cometary Coma Chemical Composition (C4) Mission are to rendezvous with a short-period comet and (1) to determine the elemental, chemical, and isotopic composition of the nucleus and (2) to characterize the chemical and isotopic nature of its atmosphere. Further, it is a goal to obtain preliminary data on the development of the coma (dust and gas composition) as a function of time and orbital position.

  20. Chemical composition in relation with biomass ash structure

    Science.gov (United States)

    Holubcik, Michal; Jandacka, Jozef

    2014-08-01

    Biomass combustion can be more complicated like combustion of fossil fuels because it is necessary to solve problems with lower ash melting temperature. It can cause a lot of problems during combustion process. Chemical composition of biomass ash has great impact on sinters and slags creation in ash because it affects structure of heated ash. In this paper was solved relation between chemical composition and structure of heated ash from three types of biomass (spruce wood, miscanthus giganteus and wheat straw). Amount of SiO2, CaO, MgO, Al2O3 and K2O was determined. Structure of heated ash was optically determined after heating to 1000 °C or 1200 °C. Results demonstrated that chemical composition has strong effect on structure and color of heated ash.

  1. Chemical composition analysis and authentication of whisky.

    Science.gov (United States)

    Wiśniewska, Paulina; Dymerski, Tomasz; Wardencki, Waldemar; Namieśnik, Jacek

    2015-08-30

    Whisky (whiskey) is one of the most popular spirit-based drinks made from malted or saccharified grains, which should mature for at least 3 years in wooden barrels. High popularity of products usually causes a potential risk of adulteration. Thus authenticity assessment is one of the key elements of food product marketing. Authentication of whisky is based on comparing the composition of this alcohol with other spirit drinks. The present review summarizes all information about the comparison of whisky and other alcoholic beverages, the identification of type of whisky or the assessment of its quality and finally the authentication of whisky. The article also presents the various techniques used for analyzing whisky, such as gas and liquid chromatography with different types of detectors (FID, AED, UV-Vis), electronic nose, atomic absorption spectroscopy and mass spectrometry. In some cases the application of chemometric methods is also described, namely PCA, DFA, LDA, ANOVA, SIMCA, PNN, k-NN and CA, as well as preparation techniques such SPME or SPE. PMID:25315338

  2. Chemical Composition of Rain Water in Lebanon

    International Nuclear Information System (INIS)

    Samples of rainfall water were collected from fifteen stations in Lebanon during the period between October 1999 and April 2000 (the rainy season in Lebanon). Nine of these stations are distributed along the urban coastal cities, from the north to the south. The remaining 6 stations which have different altitudes ranging fom 400 m to 1200 m high are distributed in the mountainous rural areas. The concentrations of major cations (H+ ,Na+, Ca2+, Mg2+ and NH+4) and major anions (Cl-, NO-3 , HCO-3 and SO2-4 are determined for the first time in Lebanon. It has been found that the rain water is not acidic, due to the presence of carbonate dust particles in the atmosphere, which arise from the natural carbonate rocks, especially predominance in the mountains and internal regions of Lebanon. The high predominance of Na+ and Cl- in the coastal investigated stations, is attributed to marine aerosol spray. The concentrations of SO-4 and NO-3 are close to the concentrations expected in typical urban areas. The correlation between the concentration of chemical species confirms the influence of natural and anthropogenic sources. (author)

  3. The chemical composition of Galactic beat Cepheids

    Science.gov (United States)

    Kovtyukh, V.; Lemasle, B.; Chekhonadskikh, F.; Bono, G.; Matsunaga, N.; Yushchenko, A.; Anderson, R. I.; Belik, S.; da Silva, R.; Inno, L.

    2016-08-01

    We determine the metallicity and detailed chemical abundances (α, iron-peak and neutron-capture elements) for the almost complete (18/24) sample of Galactic double mode Cepheids (also called beat Cepheids). Double mode Cepheids are Cepheids that pulsate in two modes simultaneously. We calibrate a new relation between their metallicity and their period ratio P1/P0. This linear relation allows to determine the metallicity of bimodal Cepheids with an accuracy of 0.03 dex in the range of [Fe/H] from +0.2 to -0.5 dex. By extrapolating the relation to Magellanic Clouds beat Cepheids, we provide their metallicity distribution function. Moreover, by using this relation, we also provide the first metallicity estimate for two double-mode F/1O Cepheids located in and beyond the Galactic bulge. Finally, we report the discovery of a super-Lithium rich double mode Cepheid V371 Per which has a Lithium abundance of logA(Li) = 3.54 ± 0.09 dex. Along with V1033 Cyg (which is an ordinary classical Cepheid), it is the second known Cepheid of such type in the Galaxy.

  4. Sensory properties and chemical composition of Sharri cheese from Kosovo

    Directory of Open Access Journals (Sweden)

    Agim Rysha

    2014-11-01

    Full Text Available Food sensory properties, analyses and chemical composition are very important because they provide information about product quality and end-user acceptance or preferences. An assessment of sensory characteristics and chemical composition of mountain sheep and cow’s-milk cheese from shepherd’s huts and industrial manufacturers in Kosovo was carried out. Consumer-oriented tests using a 9 point hedonic scale were conducted in order to determine Sharri cheese acceptability. Chemical parameters (fat content, fat content of dry matter, acidity, protein, dry matter, mineral and water content and sodium chloride content of 45-day brine cheese samples were also analyzed. Chemical and sensory assessment demonstrated large property differences. A recommendation stems from the results showing that the standardization of both artisanal and industrial production of Sharri cheese is required.

  5. Microbicidal properties and chemical composition of essential oils

    OpenAIRE

    Křůmal, K. (Kamil); Večeřa, Z. (Zbyněk)

    2014-01-01

    The microbicidal properties of 6 essential oils (EOs; Lavandula angustifolia, Cymbopogon nardus, Citrus aurantifolia, Juniperus communis, Myrtus communis and Cinnamomum zeylanicum ) for 17 microorganisms were determined using the vapour-agar contact method. The most effective EO (i.e. Lavandula angustifolia ) whose volatile components provided the sufficient microbicidal properties was chosen for detailed study of chemical composition.

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

    DEFF Research Database (Denmark)

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

    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...

  7. Chemical composition and antimicrobial activity of Polish herbhoneys.

    Science.gov (United States)

    Isidorov, V A; Bagan, R; Bakier, S; Swiecicka, I

    2015-03-15

    The present study focuses on samples of Polish herbhoneys (HHs), their chemical composition and antimicrobial activity. A gas chromatography-mass spectrometry (GC-MS) method was used to analyse eight samples of herbal honeys and three samples of nectar honeys. Their antimicrobial activities were tested on selected Gram-positive (Bacillus cereus, Staphylococcus aureus, Staphylococcus schleiferi) and Gram-negative (Escherichia coli) bacteria, as well as on pathogenic fungi Candida albicans. Ether extracts of HHs showed significant differences in composition but the principal groups found in the extracts were phenolics and aliphatic hydroxy acids typical of royal jelly and unsaturated dicarboxylic acids. In spite of the differences in chemical composition, antimicrobial activity of the extracts of HHs against all the tested microorganisms except E. coli was observed. PMID:25308646

  8. Fast, Contactless Monitoring of the Chemical Composition of Raw Materials

    Science.gov (United States)

    Ivanov, O.; Stoyanov, Zh.; Stoyanov, B.; Nadoliisky, M.; Vaseashta, Ashok

    A technique to monitor chemical composition of materials during manufacturing of ceramic products, in particular - of bricks, is investigated. The technique of monitoring is likely to offset environmental pollution and save energy. For this purpose, we use the Surface photo charge effect, which is generated for each solid body interacting with electromagnetic field. The measurement is express and can be performed in-situ in production conditions. The experimental work has shown that different samples of the investigated materials with different compositions produce different signals specific to each sample. For the same material, the signal varies with the change in chemical composition. More specifically, it is shown that for the material from which the bricks are fired, the signal is a function of the percentage of coal sludge. The results indicate that the characterization technique as a viable technique for control of incoming raw materials.

  9. 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.

  10. Features of a chemical composition of dry leaves of Steviavebaudiana

    Directory of Open Access Journals (Sweden)

    Irina Borisovna Krasina

    2016-05-01

    Full Text Available This work is dedicated to the study of a chemical composition of dry leaves of Stevia. Dry leaves of Stevia contain diterpene glycosides that contribute to their sweet taste, which makes possible the use of Stevia as a sugar substitute in a production of flour confectionery products. The evaluation of amino acid composition of dried leaves of Stevia showed that their composition includes 7 essential amino acids, among them the limiting amino acid is valine.During experimental researches it was established that they are containing in a sufficient quantity water-soluble and fat-soluble vitamins in their composition. We have studied the effect of processing conditions on the degree of milling of dry leaves of Stevia. It was revealed that the pressure of 5 MPa in the contact zone of the working elements do not guarantee a product with a desired degree of milling. Milling of dried leaves of Stevia at a pressure equal to 10 MPa, allows achieving a high degree of size reduction with a simultaneous formation of the main physical and chemical characteristics of amilledproduct. It was established that granulometric composition of dry leaves of Stevia, obtained by milling in a rotor-roller disintegrator, presents the highest content of particles with a size from 5 to 30 μm, ensuring high consumer properties of the obtained biologically active additives (BAA.

  11. Surface nanosegregation of the chemical composition of complex oxides

    International Nuclear Information System (INIS)

    A brief review of theoretical and experimental studies in the field of surface nanosegregation of chemical composition of oxides SrTiO3, LiNbO3, LiTaO3, Gd2(MoO4)3, KNbO3, PbFe0.5Nb0.5O3, induced by temperature and other factors, is provided. Results of experimental studies of the relevant oxide monocrystals by the methods of electron spectrometry and model presentations suggest diffusion mechanism of segregation. It proved possible to predict the character of changes in surface composition of the oxides on the basis of the models considered

  12. Chemical composition and medicinal significance of Fagonia cretica: a review.

    Science.gov (United States)

    Qureshi, Huma; Asif, Saira; Ahmed, Haroon; Al-Kahtani, Hassan A; Hayat, Khizar

    2016-01-01

    Members of the family Zygophyllaceae are distributed in arid areas of the world and are traditionally used against various health insults ranging from skin lesions to lethal cancer. Fagonia cretica Linn. is a plant having novel compounds responsive in diseases that are still considered as incurable or are curable with serious side effects. Researchers, particularly of the Asian region elaborately studied the chemical composition and pharmacological activities of this plant. But further studies are still required to evaluate this plant in clinical trials in order to save humanity from synthetic chemical drugs yet disputed as 'friends or foe'. PMID:25921950

  13. Treatment of chemical waste piassava for application in polymeric composites

    International Nuclear Information System (INIS)

    Piassava fibers were investigated with the aim of adding new business value. The surface of the fibers were treated with NaOH and H2SO4 for 1 h at room temperature. The samples were characterized by FTIR, TGA, DSC, chemical composition, XRD, SEM and tensile tests. The micrographs of the fibers showed that treatment with NaOH cleaned the fiber surface of a large amount of impurities and cause fibrillation. Chemical analysis, using the Van Soest method, showed that the palm fiber is a fiber rich in lignin, as evidenced by their brown color and with alkali treatment there was partial removal of hemicellulose and lignin, increasing the crystallinity index of the fiber, observed by XRD. The acid treatment caused no significant changes in the properties of the fiber. Therefore, the mercerisation was efficient in the fiber of palm fiber, improving their properties, enabling thus their use as reinforcement in polymer composites. (author)

  14. Chemical composition of material fractions in Danish household waste

    DEFF Research Database (Denmark)

    Riber, Christian; Petersen, Claus; Christensen, Thomas Højlund

    2009-01-01

    The chemical composition of Danish household waste was determined by two approaches: a direct method where the chemical composition (61 substances) of 48 material fractions was determined after hand sorting of about 20 tonnes of waste collected from 2200 households; and an indirect method where...... batches of 80-1200 tonnes of unsorted household waste was incinerated and the content of the waste determined from the content of the outputs from the incinerator. The indirect method is believed to better represent the small but highly contaminated material fractions (e,g., batteries) than the direct...... method, because of the larger quantities included and the more homogenous material to sample from. Differences between the direct and the direct methods led to corrections in the of heavy metal concentration of a few fractions. The majority of the energy content of the waste originates from organic waste...

  15. Chemical Composition, Antifungal and Insecticidal Activities of Hedychium Essential Oils

    OpenAIRE

    Kanniah Rajasekaran; Jian Chen; BECNEL, JAMES J.; Natasha M. Agramonte; Bernier, Ulrich R.; Maia Tsikolia; Kemal Husnu Can Baser; Betul Demirci; David E. Wedge; Nurhayat Tabanca; Sampson, Blair J.; Hamidou F. Sakhanokho; James M. Spiers

    2013-01-01

    The antimicrobial properties of essential oils have been documented, and their use as “biocides” is gaining popularity. The aims of this study were to analyze the chemical composition and assess the biological activities of Hedychium essential oils. Oils from 19 Hedychium species and cultivars were analyzed by gas chromatography (GC) and gas chromatography-mass spectrometry (GC-MS) techniques. The antifungal and insecticidal activities of these oils were tested against Colletotrichum acutatum...

  16. Stevia rebaudiana Bertoni – chemical composition and functional properties

    OpenAIRE

    Katarzyna Marcinek; Zbigniew Krejpcio

    2015-01-01

    Sweetleaf (Stevia rebaudiana Bertoni), currently investigated by many researchers, has been known and used for more than a thousand years indigenous tribes of South America, who called it “kaa-hee” (“sweet herb”). Thanks to its chemical composition and processability sweetleaf may be an alternative for synthetic sweeteners. Nutritional and health-promoting aspects of Stevia rebaudiana are presently being studied in many research centres. The aim of this study is to pre...

  17. Chemical Composition of Essential Oil from Marrubium Vulgare L. Leaves

    OpenAIRE

    Bayir, Burcu; Gündüz, Hatice; Usta, Tuba; Şahin, Esma; Özdemir, Zeynep; Kayır, Ömer; Sen, Özkan; Akşit, Hüseyin; Elmastaş, Mahfuz; Erenler, Ramazan

    2014-01-01

    – The essential oils are significant for pharmaceutical, food and cosmetic industries. Marrubium vulgare L. has been used as a traditional medicine to treat the various illnesses. The chemical composition of the essential oil from leaves of Marrubium vulgare L.was obtained by steam distillation using the Clevenger apparatus. The oil was analyzed by gas chromatography and mass spectrometry (GC-MS). The main constituent of the oil was α-pinene (28.85%)

  18. Composition and utilization of cellulose for chemicals from agricultural residues

    Energy Technology Data Exchange (ETDEWEB)

    Sciamanna, A.F.; Freitas, R.P.; Wilke, C.R.

    1977-12-01

    This study was undertaken for several reasons. Firstly, because of the scarcity of data on the composition of certain agricultural residues generated predominantly in California, it could only be inferred from the published composition of agricultural grains and wood what the carbohydrate composition of the residue straw, stems, and roots might be. Published methods of analysis on wood and grains were adapted or modified to suit these materials, resulting in an analytical system applicable to these residues. Secondly, a series of chemical pretreatments were studied to see if sugar production by enzymatic hydrolysis might be improved. Also these studies are used as a basis of generating the data for chemical engineering parameters of the Berkeley process. Since lignin is ultimately used as a feed back energy source in the Berkeley process, it is not necessary for it to be in the form of a relatively low weight polymer. Therefore, a study on the use of recoverable chemical solvents for dilignification by solution, rather than by a depolymerization reaction is indicated.

  19. Chemical composition and surface charge properties of montmorillonite

    Institute of Scientific and Technical Information of China (English)

    LIU Xiao-wen; HU Min; HU Yue-hua

    2008-01-01

    The effects of the cell parameter and chemical composition on the surface charge properties of five kinds of different colour montmorillonites were studied. The results indicate that the surface isoelectric point(IEP) of the montmorillonite shows positive correlation with the mass fractions of Fe2O3 and K20, but it has little relation to the mass fractions of other chemical compositions. At around pH=6.8, the surface zeta potential of the montmorillonite shows the negative relationship with the mass fractions of Fe2O3 and MgO, but it does not linearly correlate to the mass fractions of other chemical compositions. Cell parameter(b0) of the montmofillonite expresses negative linear relationship with mass fractions of K2O and Na2O, so does c0sinβ with mass fractions of SiO2 and Fe2O3. And there is no specific relationship between bo and IEP of different montmori Uonites, but there is positive correlation between c0sinβ and IEP of different montmorillonite samples.

  20. Peculiarities of chemical composition of sainfoin seeds powder

    Directory of Open Access Journals (Sweden)

    Natalia Aleksandrovna Tarasenko

    2015-09-01

    Full Text Available This paper is devoted to studying chemical composition of the powder of the seeds of non-traditional legume, sainfoin. The experimental studies showed that crushed seeds of sainfoin make a flowing fine powder of light brown color with a pleasant unpronounced specific smell with floral notes. The taste is grassy with the after-taste typical for legumes. The chemical composition of sainfoin seeds is dominated by proteins and fiber, and fat content does not exceed 8%. The total content of amino-acids is 26.94/100 g of the product, with the share of indispensable ones being 37.85%. The limiting amino acid is tryptophan (48.0 %. By the composition of essential amino acids, proteins of sainfoin seeds are slightly inferior to the proteins of soybean seeds, but are better than the proteins of peanut seeds. The composition of fatty acid of the lipid complex of sainfoin seeds is dominated by (over 40% of the total linolenic ω-3 acid with sufficiently low (less than 20% of the total content of linoleic ω-6 acid. The lipid composition of sainfoin seeds, along with triacylglycerols, contains about 40% of related lipids, which are dominated by sterols, aliphatic alcohols, phospholipids and tocopherols. All this makes the lipid complex of sainfoin seed a promising means of adjusting fatty acids composition in food products of functional and specialized purpose, dietary supplements, and a valuable raw material for creating pharmaceutical substances and preparations. Adding sainfoin seeds powder into the nutritive medium has no inhibitory effect on development of the tested organism. At the same time, 58% of the organism's physiological need for protein is satifsied, as compared to caseine.

  1. Preliminary study of chemical compositional data from Amazon ceramics

    Energy Technology Data Exchange (ETDEWEB)

    Toyota, Rosimeiri G.; Munita, Casimiro S.; Luz, Fabio A. [Instituto de Pesquisas Energeticas e Nucleares (IPEN), Sao Paulo, SP (Brazil)]. E-mail: rosimeiritoy@yahoo.com.br; Neves, Eduardo G. [Museu de Arqueologia e Etnolgia, Sao Paulo, SP (Brazil)]. E-mail: egneves@usp.br; Oliveira, Paulo M.S. [Sao Paulo Univ., SP (Brazil). Escola Politecnica. Inst. de Matematica e Estatistica]. E-mail: poliver@usp.br

    2005-07-01

    Eighty seven ceramic samples from Acutuba, Lago Grande and Osvaldo archaeological sites located in the confluence of the rivers Negro and Solimoes were submitted to chemical analysis using instrumental neutron activation analysis to determine As, Ba, Ce, Co, Cr, Cs, Eu, Fe, Hf, K, La, Lu, Rb, Na, Nd, Sb, Sc, Sm, Ta, Tb, Th, Yb, Zn, and U. The database were studied using the Mahalanobis distance, and discriminant analysis. The results showed that the ceramics of each site differ from each other in chemical composition and that they form three different groups. Chemical classification of the ceramics suggests that vessels were made locally, as only ceramics from the same area show homogeneity of data. (author)

  2. Preliminary study of chemical compositional data from Amazon ceramics

    International Nuclear Information System (INIS)

    Eighty seven ceramic samples from Acutuba, Lago Grande and Osvaldo archaeological sites located in the confluence of the rivers Negro and Solimoes were submitted to chemical analysis using instrumental neutron activation analysis to determine As, Ba, Ce, Co, Cr, Cs, Eu, Fe, Hf, K, La, Lu, Rb, Na, Nd, Sb, Sc, Sm, Ta, Tb, Th, Yb, Zn, and U. The database were studied using the Mahalanobis distance, and discriminant analysis. The results showed that the ceramics of each site differ from each other in chemical composition and that they form three different groups. Chemical classification of the ceramics suggests that vessels were made locally, as only ceramics from the same area show homogeneity of data. (author)

  3. Chemical Composition of Organic Aerosol Particles over the Remote Ocean

    Science.gov (United States)

    Russell, L. M.; Frossard, A. A.; Keene, W. C.; Kieber, D. J.; Quinn, P.; Bates, T. S.

    2012-12-01

    Marine aerosol particles play an important role in Earth's radiative balance, yet the composition of the organic fraction of these important particles remains largely unconstrained. The composition of marine aerosol particles was measured in remote marine regions on board the R/V Atlantis during the CalNex 2010 campaign in May and June 2010, on board the R/V Point Sur during the E-PEACE campaign in July 2011, and on board the R/V Ronald Brown during the WACS campaign in August 2012. To understand the factors that control this composition, we compared the organic components of these particles to models of primary marine aerosol - i.e. those generated from bubbled and atomized seawater. The organic chemical composition was characterized by Fourier Transform Infrared (FTIR) spectroscopy to determine the functional group composition and high resolution time of flight aerosol mass spectrometer (HR-ToF-AMS) to identify characteristic mass fragments. Cluster analysis of FTIR organic spectra was used to identify different spectral signatures associated with location, seawater composition, and ambient conditions. Typical submicron organic mass (OM) concentrations were less than 0.80 μg m-3. The overall organic compositions of marine aerosol particles and generated seawater models were similar, with large fractions of organic hydroxyl functional groups in each. One cluster of FTIR spectra from the eastern Pacific showed the highest fraction of hydroxyl functional groups (77%) occurred during periods of high chlorophyll concentrations and high wind speeds (more than 10 m s-1). Detailed spectral comparisons revealed unique minor features that may be driven both by meteorology and regional differences in seawater composition for these and past studies.

  4. Chemical composition of dissolved organic matter draining permafrost soils

    Science.gov (United States)

    Ward, Collin P.; Cory, Rose M.

    2015-10-01

    Northern circumpolar permafrost soils contain roughly twice the amount of carbon stored in the atmosphere today, but the majority of this soil organic carbon is perennially frozen. Climate warming in the arctic is thawing permafrost soils and mobilizing previously frozen dissolved organic matter (DOM) from deeper soil layers to nearby surface waters. Previous studies have reported that ancient DOM draining deeper layers of permafrost soils was more susceptible to degradation by aquatic bacteria compared to modern DOM draining the shallow active layer of permafrost soils, and have suggested that DOM chemical composition may be an important control for the lability of DOM to bacterial degradation. However, the compositional features that distinguish DOM drained from different depths in permafrost soils are poorly characterized. Thus, the objective of this study was to characterize the chemical composition of DOM drained from different depths in permafrost soils, and relate these compositional differences to its susceptibility to biological degradation. DOM was leached from the shallow organic mat and the deeper permafrost layer of soils within the Imnavait Creek watershed on the North Slope of Alaska. DOM draining both soil layers was characterized in triplicate by coupling ultra-high resolution mass spectrometry, 13C solid-state NMR, and optical spectroscopy methods with multi-variate statistical analyses. Reproducibility of replicate mass spectra was high, and compositional differences resulting from interfering species or isolation effects were significantly smaller than differences between DOM drained from each soil layer. All analyses indicated that DOM leached from the shallower organic mat contained higher molecular weight, more oxidized, and more unsaturated aromatic species compared to DOM leached from the deeper permafrost layer. Bacterial production rates and bacterial efficiencies were significantly higher for permafrost compared to organic mat DOM

  5. Values below detection limit in compositional chemical data

    International Nuclear Information System (INIS)

    Highlights: ► Less-than replacement methods for compositional chemical data. ► New model-based univariate multiplicative replacement method. ► Evaluation of competing methods performance. ► Computer code implementing the methods provided. -- Abstract: Samples representing part of a whole, usually called compositional data in statistics, are commonplace in analytical chemistry—say chemical data in percentage, ppm, or μg g−1. Their distinctive feature is that there is an inherent relationship between all the analytes constituting a chemical sample as they only convey relative information. Some compositional data analysis principles and the log-ratio based methodology are outlined here in practical terms. Besides, one often finds that some analytes are not present in sufficient concentration in a sample to allow the measuring instruments to effectively detect them. These non-detects are usually labelled as “< DL” (less-thans) in the data set, indicating that the values are below known detection limits. Many data analysis techniques require complete data sets. Thus, there is a need of sensible replacement strategies for less-thans. The peculiar nature of compositional data determines any data analysis and demands for a specialised treatment of less-thans that, unfortunately, is not usually covered in chemometrics. Some well-founded statistical methods are revisited in this paper aiming to prevent practitioners from relying on popular but untrustworthy approaches. A new proposal to estimate less-thans combining a log-normal probability model and a multiplicative modification of the samples is also introduced. Their performance is illustrated and compared on a real data set, and guidelines are provided for practitioners. Matlab and R code implementing the methods are made available for the reader

  6. Nanograined WC-Co Composite Powders by Chemical Vapor Synthesis

    Science.gov (United States)

    Ryu, Taegong; Sohn, H. Y.; Han, Gilsoo; Kim, Young-Ugk; Hwang, Kyu Sup; Mena, M.; Fang, Zhigang Z.

    2008-02-01

    Nanograined tungsten carbide (WC) Co composite powders were prepared by a chemical vapor synthesis (CVS) process that has previously been used for preparing the aluminides of titanium and nickel and other metallic and intermetallic powders at the University of Utah. To determine the optimum condition for producing nanograined WC-Co composite powders, the effects of carburization temperature, CH4 to WCl6 ratio, CH4 to H2 ratio, CoCl2 contents, and residence time of WC on the powder composition and particle size were investigated. The reduction and carburization of the vaporized chlorides by CH4-H2 mixtures produced nanograined WC and Co composite powder, which sometimes contained small levels of W2C, W, or the η (Co3W3C) phase. The presence of these incompletely carburized phases can be tolerated because they can be fully carburized during the subsequent sintering process. These phases can also be fully carburized by a separate post-treatment. The products were characterized by using X-ray diffraction (XRD) and a transmission electron microscope (TEM). As a result, nanograined WC-Co composite with the particle size less than 30 nm was obtained.

  7. Chemical Composition and Antioxidant Activity of Walnut Pollen Samples

    Directory of Open Access Journals (Sweden)

    Sina COSMULESCU

    2015-12-01

    Full Text Available Chemical composition of pollen is highly varied depending on the plant species from which it comes and has been the subject of numerous comparative studies. The aim of this study was to determine chemical composition and antioxidant activity of walnut pollen samples and compare them with those of bee pollen. Total phenols content, total flavonoids content, antioxidant activity and mineral composition were studied using walnut pollen samples from three walnut genotypes cultivated in Romania. Total phenols content was determined by colorimetric assay and their amount varied between 10.8 and 17.64 mgGAE/g per genotype. Determination of flavonoids was done by aluminium nitrate colorimetric method and total flavonoid contents in walnut pollen ranged from 7.32 to 7.95 mgQE/g. The antioxidant capacity of pollen extracts was assessed through the scavenging effects on DPPH and a concentration-dependent genotype, and it varied between 13.78 and 15.04 mg Trolox/g. In terms of mineral composition, walnut pollen appears to be a good source of potassium (859.14 mg/100 g, magnesium (263.77 mg/100 g, calcium (71.72 mg/100 g, iron (27.19 mg/100 g, sodium (10.52 mg/100 g, zinc (5.69 mg/100 g, manganese (3.98 mg/100 g, copper (1.28 mg/100 g, chromium (0.39 mg/100 g and selenium (0.036 mg/100 g. The results obtained indicate that walnut pollen is an important source of total phenols showing antioxidant properties and mineral composition that could be beneficial to human health.

  8. A bootstrap estimation scheme for chemical compositional data with nondetects

    Science.gov (United States)

    Palarea-Albaladejo, J; Martín-Fernández, J.A; Olea, Ricardo A.

    2014-01-01

    The bootstrap method is commonly used to estimate the distribution of estimators and their associated uncertainty when explicit analytic expressions are not available or are difficult to obtain. It has been widely applied in environmental and geochemical studies, where the data generated often represent parts of whole, typically chemical concentrations. This kind of constrained data is generically called compositional data, and they require specialised statistical methods to properly account for their particular covariance structure. On the other hand, it is not unusual in practice that those data contain labels denoting nondetects, that is, concentrations falling below detection limits. Nondetects impede the implementation of the bootstrap and represent an additional source of uncertainty that must be taken into account. In this work, a bootstrap scheme is devised that handles nondetects by adding an imputation step within the resampling process and conveniently propagates their associated uncertainly. In doing so, it considers the constrained relationships between chemical concentrations originated from their compositional nature. Bootstrap estimates using a range of imputation methods, including new stochastic proposals, are compared across scenarios of increasing difficulty. They are formulated to meet compositional principles following the log-ratio approach, and an adjustment is introduced in the multivariate case to deal with nonclosed samples. Results suggest that nondetect bootstrap based on model-based imputation is generally preferable. A robust approach based on isometric log-ratio transformations appears to be particularly suited in this context. Computer routines in the R statistical programming language are provided. 

  9. Clouds Composition in Super-Earth Atmospheres: Chemical Equilibrium Calculations

    Science.gov (United States)

    Kempton, Eliza M.-R.; Mbarek, Rostom

    2015-12-01

    Attempts to determine the composition of super-Earth atmospheres have so far been plagued by the presence of clouds. Yet the theoretical framework to understand these clouds is still in its infancy. For the super-Earth archetype GJ 1214b, KCl, Na2S, and ZnS have been proposed as condensates that would form under the condition of chemical equilibrium, if the planet’s atmosphere has a bulk composition near solar. Condensation chemistry calculations have not been presented for a wider range of atmospheric bulk composition that is to be expected for super-Earth exoplanets. Here we provide a theoretical context for the formation of super-Earth clouds in atmospheres of varied composition by determining which condensates are likely to form, under the assumption of chemical equilibrium. We model super-Earth atmospheres assuming they are formed by degassing of volatiles from a solid planetary core of chondritic material. Given the atomic makeup of these atmospheres, we minimize the global Gibbs free energy of over 550 gases and condensates to obtain the molecular composition of the atmospheres over a temperature range of 350-3,000 K. Clouds should form along the temperature-pressure boundaries where the condensed species appear in our calculations. The super-Earth atmospheres that we study range from highly reducing to oxidizing and have carbon to oxygen (C:O) ratios that are both sub-solar and super-solar, thereby spanning a diverse range of atmospheric composition that is appropriate for low-mass exoplanets. Some condensates appear across all of our models. However, the majority of condensed species appear only over specific ranges of H:O and C:O ratios. We find that for GJ 1214b, KCl is the primary cloud-forming condensate at solar composition, in agreement with previous work. However, for oxidizing atmospheres, where H:O is less than unity, K2SO4 clouds form instead. For carbon-rich atmospheres with super-solar C:O ratios, graphite clouds additionally appear. At

  10. Dynamics of the chemical composition of rainwater throughout Hurricane Irene

    Directory of Open Access Journals (Sweden)

    K. M. Mullaugh

    2013-03-01

    Full Text Available Sequential sampling of rainwater from Hurricane Irene was carried out in Wilmington, NC, USA on 26 and 27 August 2011. Eleven samples were analyzed for pH, major ions (Cl−, NO3−, SO42−, Na+, K+, Mg2+, Ca2+, NH4+, dissolved organic carbon (DOC and hydrogen peroxide (H2O2. Hurricane Irene contributed 16% of the total rainwater and 18% of the total chloride wet deposition received in Wilmington NC during all of 2011. This work highlights the main physical factors influencing the chemical composition of tropical storm rainwater: wind speed, wind direction, back trajectory and vertical mixing, time of day and total rain volume. Samples collected early in the storm, when winds blew out of the east, contained dissolved components indicative of marine sources (salts from sea spray and low DOC. The sea-salt components in the samples had two maxima in concentration during the storm the first of which occurred before the volume of rain had sufficiently washed out sea salt from the atmosphere and the second when back trajectories showed large volumes of marine surface air were lifted. As the storm progressed and winds shifted to a westerly direction, the chemical composition of the rainwater became characteristic of terrestrial storms (high DOC and NH4+ and low sea salt. This work demonstrates that tropical storms are not only responsible for significant wet deposition of marine components to land, but terrestrial components can also become entrained in rainwater, which can then be delivered to coastal waters via wet deposition. This study also underscores why analysis of one composite sample can lead to an incomplete interpretation of the factors that influence the chemically divergent analytes in rainwater during extreme weather events.

  11. Effects of air pollutants on epicuticular wax chemical composition

    International Nuclear Information System (INIS)

    There are numerous reports in the literature of modifications to epicuticular wax structure as a consequence of exposure to air pollutants. Most authors have used scanning electron microscopy (SEM) to describe changes in wax crystallite morphology or distribution. ''Erosion'' or ''weathering'' of crystalline structure into an amorphous state is the most common observation, particularly in the case of conifer needles having the characteristic tube crystallites comprised of nonacosan-10-ol. Wax structure is largely determined by its chemical composition. Therefore, many of the reported changes in wax structure due to air pollutants probably arise from direct interactions between pollutants such as ozone and wax biosynthesis. The literature describing changes in wax composition due to pollutants is briefly reviewed. New evidence is introduced in support of the hypothesis for a direct interaction between air pollutants and epicuticular wax Biosynthesis. (orig.)

  12. Chemical composition and health effects of Tartary buckwheat.

    Science.gov (United States)

    Zhu, Fan

    2016-07-15

    Tartary buckwheat (Fagopyrum tataricum) contains a range of nutrients including bioactive carbohydrates and proteins, polyphenols, phytosterols, vitamins, carotenoids, and minerals. The unique composition of Tartary buckwheat contributes to their various health benefits such as anti-oxidative, anti-cancer, anti-hypertension, anti-diabetic, cholesterol-lowering, and cognition-improving. Compared with the more widely cultivated and utilised common buckwheat (F. esculentum), Tartary buckwheat tends to contain higher amounts of certain bioactive components such as rutin, therefore, showing higher efficiency in preventing/treating various disorders. This review summarises the current knowledge of the chemical composition of Tartary buckwheat, and their bio-functions as studied by both in vitro and in vivo models. Tartary buckwheat can be further developed as a sustainable crop for functional food production to improve human health. PMID:26948610

  13. Nepheline structural and chemical dependence on melt composition

    Energy Technology Data Exchange (ETDEWEB)

    Marcial, José; Crum, Jarrod; Neill, Owen; McCloy, John

    2016-02-01

    Nepheline crystallizes upon slow-cooling in some melts concentrated in Na2O and Al2O3, which can result in a residual glass phase of low chemical durability. Nepheline can incorporate many components often found in high-level waste radioactive borosilicate glass, including glass network ions (e.g., Si, Al, Fe), alkali metals (e.g., Cs, K, Na, and possibly Li), alkaline-earth metals (e.g., Ba, Sr, Ca, Mg), and transition metals (e.g., Mn, and possibly Cr, Zn, Ni). When crystallized from melts of different compositions, nepheline chemistry varies as a function of starting glass composition. Five simulated high level nuclear waste borosilicate glasses shown to crystallize large fractions of nepheline on slow cooling, were selected for study. These melts constituted a range of Al2O3, B2O3, CaO, Na2O, K2O, Fe2O3, and SiO2 compositions. Compositional analyses of nepheline crystals in glass by electron probe micro-analysis (EPMA) indicate that boron is unlikely to be present in any significant concentration, if at all, in nepheline. Also, several models are presented for calculating the fraction of vacancies in the nepheline structure.

  14. Chemical selforganization of composite catalysts during catalytic reactions

    Energy Technology Data Exchange (ETDEWEB)

    Imbihl, Ronald, E-mail: imbihl@pci.uni-hannover.de [Institut fuer Physikalische Chemie und Elektrochemie, Leibniz-Universitaet Hannover, Callinstrasse 3-3a, D-30167 Hannover (Germany)

    2012-10-15

    Highlights: Black-Right-Pointing-Pointer Selforganization of composite catalysts under reaction conditions. Black-Right-Pointing-Pointer Reactive phase separation causes demixing of catalysts. Black-Right-Pointing-Pointer Condensation patterns in supported oxide catalysts. -- Abstract: Recent progress in the study of selforganization phenomena in catalytic reactions on multi-component surfaces is reviewed. As chemically more complex systems a Rh(1 1 1) surface with ultra-thin vanadium oxide layers ({theta}{sub V} < 0.5 MLE) and a bimetallic Rh(1 1 1)/Ni surface, both subjected to the H{sub 2} + O{sub 2} reaction, were chosen. Applying spatially resolving methods in situ, it is shown that under reaction conditions a reversible redistribution of the components of the catalyst occurs. The redistribution processes are essentially driven by the different chemical affinities of the components to reacting species.

  15. Titan's lakes chemical composition: sources of uncertainties and variability

    CERN Document Server

    Cordiera, D; Luninee, J I; Lebonnoisg, S; Rannouh, P; Lavvasf, P; Loboi, L Q; Ferreirai, A G M

    2011-01-01

    Between 2004 and 2007 the instruments of the CASSINI spacecraft discovered hydrocarbon lakes in the polar regions of Titan. We have developed a lake-atmosphere equilibrium model allowing the determination of the chemical composition of these liquid areas. The model is based on uncertain thermodynamic data and precipitation rates of organic species predicted to be present in the lakes and seas that are subject to spatial and temporal variations. Here we explore and discuss the influence of these uncertainties and variations. The errors and uncertainties relevant to thermodynamic data are simulated via Monte-Carlo simulations. Global Circulation Models (GCM) are also employed in order to investigate the possibility of chemical asymmetry between the south and the north poles, due to differences in precipitation rates. We find that mole fractions of compounds in the liquid phase have a high sensitivity to thermodynamic data used as inputs, in particular molar volumes and enthalpies of vaporization. When we combin...

  16. Physical Characterization and Steam Chemical Reactivity of Carbon Fiber Composites

    Energy Technology Data Exchange (ETDEWEB)

    Anderl, Robert Andrew; Pawelko, Robert James; Smolik, Galen Richard

    2001-05-01

    This report documents experiments and analyses that have been done at the Idaho National Engineering and Environmental Laboratory (INEEL) to measure the steam chemical reactivity of two types of carbon fiber composites, NS31 and NB31, proposed for use at the divertor strike points in an ITER-like tokamak. These materials are 3D CFCs constituted by a NOVOLTEX preform and densified by pyrocarbon infiltration and heat treatment. NS31 differs from NB31 in that the final infiltration was done with liquid silicon to reduce the porosity and enhance the thermal conductivity of the CFC. Our approach in this work was twofold: (1) physical characterization measurements of the specimens and (2) measurements of the chemical reactivity of specimens exposed to steam.

  17. Chemical composition and temperature influence on honey texture properties.

    Science.gov (United States)

    Oroian, Mircea; Paduret, Sergiu; Amariei, Sonia; Gutt, Gheorghe

    2016-01-01

    The aim of this study is to evaluate the chemical composition and temperatures (20, 30, 40, 50 and 60 °C) influence on the honey texture parameters (hardness, viscosity, adhesion, cohesiveness, springiness, gumminess and chewiness). The honeys analyzed respect the European regulation in terms of moisture content and inverted sugar concentration. The texture parameters are influenced negatively by the moisture content, and positively by the °Brix concentration. The texture parameters modelling have been made using the artificial neural network and the polynomial model. The polynomial model predicted better the texture parameters than the artificial neural network. PMID:26787962

  18. Testing chemical composition of highest energy comic rays

    Czech Academy of Sciences Publication Activity Database

    Nosek, D.; Vícha, Jakub; Nosková, J.; Ebr, Jan

    Singapore : International Union of Pure and Applied Physics (IUPAP), 2013, s. 0472. ISBN 978-85-89064-29-3. [The 33rd International Cosmic Ray Conference (ICRC2013). Rio de Janeiro (BR), 02.07.2013-09.07.2013] R&D Projects: GA MŠk(CZ) LG13007 Institutional support: RVO:68378271 Keywords : ultra-high energy cosmic rays * chemical composition Subject RIV: BF - Elementary Particles and High Energy Physics http://www.cbpf.br/~icrc2013/proc_icrc2013.html

  19. Chemical composition of Eu2+ luminescence in the barium hexaaluminates

    International Nuclear Information System (INIS)

    This paper consists of two parts. In the first part the chemical composition of two kinds of barium hexaaluminate (one poor and one rich in barium) is explained using the local electroneutrality concept. In the second part a reinvestigation of the Eu2+ luminescence in these compounds is reported. The emission spectrum of each of the two compounds shows a blue and a green emission bank. The blue emission bank is ascribed to Eu2+ ions at barium sites, whereas the green emission band is identified with Eu2+ ions incorporated at aluminum sites within spinel blocks of the structure

  20. Arrival directions and chemical composition of ultrahigh energy cosmic rays

    International Nuclear Information System (INIS)

    To estimate the chemical composition of ultrahigh energy cosmic rays we apply an approach using the well established magnitude and character of the galactic magnetic field and also both theoretical and experimental distributions of showers in galactic latitude. Arrival directions of cosmic rays in the energy region of (0.8-4)x1019 eV in galactic latitude are consistent with theoretical calculations, if cosmic rays are mainly heavy nuclei. An excess flux of cosmic rays at ∼ 1019 eV from the galactic plane is found

  1. Chemical Composition of the Essential Oil of Salvia aethiopis L.

    OpenAIRE

    Güllüce, Medine; ÖZER, Hakan; BARIŞ, Özlem; DAFERERA, Dimitri; ŞAHİN, Fikrettin; Polissiou, Moschos

    2006-01-01

    The chemical composition of the essential oil obtained by hydrodistillation from the aerial parts of Salvia aethiopis was analyzed by employing GC-MS. Thirty-two components (98.0% of the total oil) were identified in the essential oil of S. aethiopis. The main components of this oil were germacrene D (29.0%), a-copaene (19.8%), b-cubebene + b-elemene (9.9%), bicyclogermacrene (9.3%), d cadinene (8.7%), and b-caryophyllene (7.3%).

  2. Chemical composition and quality of sweet sorghum and maize silages

    OpenAIRE

    PODKÓWKA, Zbigniew; Lucyna PODKÓWKA

    2011-01-01

    Sweet sorghum (Sorghum saccharatum) silage, maize (Zea mays) silage, and sorghum and maize (1:1) silage were investigated. The silages were analysed for chemical composition, quality and aerobic stability. Dry matter was the lowest (20.88%) in sorghum silage and the highest (37.45%) in maize silage. In sorghum silage, the concentration of crude ash and crude fibre was higher, and that of crude protein, crude fat and N-free extractives lower compared to maize silage. Neutral detergent fibre an...

  3. CHEMICAL COMPOSITIONS AND RESISTANT STARCH CONTENT IN STARCHY FOODS

    Directory of Open Access Journals (Sweden)

    Anuchita Moongngarm

    2013-01-01

    Full Text Available Resistant Starch (RS is one of nature’s most interesting bioactive compounds. There is a wide variety of starchy food plants in Thailand that are good sources of RS, but they have not been well studied. As such, this study was carried out to investigate the potential food source of RS. Twenty-two promising food plants were selected. The samples included (1 cereals comprised of five long grain rice of O. sativa L. and sweet corn, (2 six species of root and tuber crops, (3 green banana fruits (Musa sapientum L. composed of ABB group, AAB group and AAA group at the first stage of ripening and (4 legume seeds included cowpea seeds (3 different cultivars, red bean, red kidney bean and mung bean. All food plants were determined for chemical compositions, resistant starch, non-resistant starch, total starch and amylose content. The study found that the starchy foods varied in their chemical compositions. The major composition of all foods was carbohydrate ranging between 58.19 (in black speck cow pea and 87.21% (in cassava root, whilst the fat, ash and fiber were observed only in small quantities. The protein content was highest in legume seeds (20.78 to 27.22%. For the study on starch compositions, green bananas contained highest amount of resistant starch ranging between 35.14 and 45.87%, indicating that more than a half of total starch in banana RS content varying from 35.14 to 45.87%, whereas the RS content of legumes ranging from 2.33 to 10.63% and 1.16 to 4.85% in cereal grains. Most of the starchy food plants contained moderate to high level of amylose (11.45-34.85%, except the waxy rice (2.72%.

  4. Public Health Risk Conditioned by Chemical Composition of Ground Water

    Science.gov (United States)

    Yankovich, E.; Osipova, N.; Yankovich, K.; Matveenko, I.

    2016-03-01

    The article studies the public health potential risk originated from water consumption and estimated on the basis of the groundwater chemical composition. We have processed the results of chemical groundwater analysis in different aquifers of Tomsk district (Tomsk Oblast, Russia). More than 8400 samples of chemical groundwater analyses were taken during long-term observation period. Human health risk assessment of exposure to contaminants in drinking water was performed in accordance with the risk assessment guidance for public health concerning chemical pollution of the environment (Russian reference number: 2.1.10.1920-04-M, 2004). Identified potential risks were estimated for consuming water of each aquifer. The comparative analysis of water quality of different aquifers was performed on the basis of the risk coefficient of the total non-carcinogenic effects. The non-carcinogenic risk for the health of the Tomsk district population due to groundwater consumption without prior sanitary treatment was admitted acceptable. A rather similar picture is observed for all aquifers, although deeper aquifers show lower hazard coefficients.

  5. Determining the chemical composition of cloud condensation nuclei

    Energy Technology Data Exchange (ETDEWEB)

    Williams, A.L.; Rothert, J.E.; McClure, K.E. (Illinois State Water Survey, Champaign, IL (United States)); Alofs, D.J.; Hagen, D.E.; White, D.R.; Hopkins, A.R.; Trueblood, M.B. (Missouri Univ., Rolla, MO (USA). Cloud and Aerosol Science Lab.)

    1992-02-01

    This second progress report describes the status of the project one and one-half years after the start. The goal of the project is to develop the instrumentation to collect cloud condensation nuclei (CCN) in sufficient amounts to determine their chemical composition, and to survey the CCN composition in different climates through a series of field measurements. Our approach to CCN collection is to first form droplets on the nuclei under simulated cloud humidity conditions, which is the only known method of identifying CCN from the background aerosol. Under cloud chamber conditions, the droplets formed become larger than the surrounding aerosol, and can then be removed by inertial impaction. The residue of the evaporated droplets represents the sample to be chemically analyzed. Two size functions of CCN particles are collected by first forming droplets on the large particles are collected by first forming droplets on the large CCN in a haze chamber at 100% relative humidity, and then activating the remaining CCN at 1% supersaturation in a cloud chamber. The experimental apparatus is a serious flow arrangement consisting of an impactor to remove the large aerosol particles, a haze chamber to form droplets on the remaining larger CCN, another impactor to remove the haze droplets containing the larger CCN particles for chemical analysis, a continuous flow diffusion (CFD) cloud chamber to form droplets on the remaining smaller CCN, and a third impactor to remove the droplets for the small CCN sample. Progress is documented here on the development of each of the major components of the flow system. Chemical results are reported on tests to determine suitable wicking material for the different plates. Results of computer modeling of various impactor flows are discussed.

  6. Chemical vapor deposited fiber coatings and chemical vapor infiltrated ceramic matrix composites

    Energy Technology Data Exchange (ETDEWEB)

    Kmetz, M.A.

    1992-01-01

    Conventional Chemical Vapor Deposition (CVD) and Organometallic Chemical Vapor Deposition (MOCVD) were employed to deposit a series of interfacial coatings on SiC and carbon yarn. Molybdenum, tungsten and chromium hexacarbonyls were utilized as precursors in a low temperature (350[degrees]C) MOCVD process to coat SiC yarn with Mo, W and Cr oxycarbides. Annealing studies performed on the MoOC and WOC coated SiC yarns in N[sub 2] to 1,000[degrees]C establish that further decomposition of the oxycarbides occurred, culminating in the formation of the metals. These metals were then found to react with Si to form Mo and W disilicide coatings. In the Cr system, heating in N[sub 2] above 800[degrees]C resulted in the formation of a mixture of carbides and oxides. Convention CVD was also employed to coat SiC and carbon yarn with C, Bn and a new interface designated BC (a carbon-boron alloy). The coated tows were then infiltrated with SiC, TiO[sub 2], SiO[sub 2] and B[sub 4]C by a chemical vapor infiltration process. The B-C coatings were found to provide advantageous interfacial properties over carbon and BN coatings in several different composite systems. The effectiveness of these different coatings to act as a chemically inert barrier layer and their relationship to the degree of interfacial debonding on the mechanical properties of the composites were examined. The effects of thermal stability and strength of the coated fibers and composites were also determined for several difference atmospheres. In addition, a new method for determining the tensile strength of the as-received and coated yarns was also developed. The coated fibers and composites were further characterized by AES, SEM, XPS, IR and X-ray diffraction analysis.

  7. STUDYING THE CHEMICAL COMPOSITION OF ALCOHOLIC EXTRACT SCHROTH RAPE

    Directory of Open Access Journals (Sweden)

    Елена Эдуардовна Чигиринец

    2014-09-01

    Full Text Available As the authors found that a promising material for a volatile atmospheric corrosion inhibitor is the use of waste generated in obtaining oil from rapeseed (family Brassicaceae, namely rapeseed meal, appropriate research was qualitative and quantitative determination of its basic compounds. Also found that the inhibition efficiency is extreme character with a maximum protective capacity for 2 hours. Why was it necessary to study changes in the composition of the extract in the evaporation process, and identification of compounds that do not take part in the formation of the film, that is remaining in the non-volatile sludge. The subject of this study is to extract 2-proрanol rapeseed cake extract . The purpose of work - a study of its component composition, namely, volatile and non-volatile compounds. The volatile chemical composition of the rapeseed cake extract involves glycosides, nucleosides, ketone, aldehyde, fatty acids, sterol and alkaloids. The most important compounds in rapeseed cake are: Guanosine , Sucrose , Xanthosine, 3',5'-Dimethoxyacetophenone Benzaldehyde, 4-hydroxy-3,5-dimethoxy, Acetic, Oleic, Linoleic and Palmitic acid and Sterols.

  8. Chemical compositions of lavas from Myoko volcano group

    International Nuclear Information System (INIS)

    In the volcanic rocks produced in island arc and continental margin arc, the phenomena of magma mixing is observed considerably generally. The research on these phenomena has been carried out also in Japan, and the periodically refilled magma chamber model has been proposed. In this report, the results of the photon activation analysis for the volcanic rock samples of Myoko volcano, for which the magma chamber model that the supply of basalt magma is periodically received was proposed, and of which the age of eruption and the stratigraphy are clearly known, are shown, and the above model is examined together with the published data of fluorescent X-ray analysis and others. The history of activities and the rate of magma extrusion of Myoko volcano group are described. The modal compositions of the volcanic rock samples of Myoko and Kurohime volcanos, for which photon activation analysis was carried out, are shown and discussed. The results of the analysis of the chemical composition of 39 volcanic rock samples from Myoko, Kurohime and Iizuna volcanos are shown. The primary magma in Myoko volcano group, the crystallization differentiation depth and moisture content of magma in Myoko and Kurohime volcanos, the presumption of Felsic and Mafic end-members in R type andesite in Myoko volcano group, and the change of magma composition with lapse of time are described. (K.I.)

  9. Calculation of complex chemical equilibrium compositions of composite rocket propellants combustion products

    Directory of Open Access Journals (Sweden)

    NIKOLA KILIBARDA

    2000-11-01

    Full Text Available An adequate method for calculating chemical equilibrium in a predominantly gaseous, multi-component reactive mixture was investigated and successfully applied. This method involves the stated equilibrium reaction scheme, including, first, the formation of chemical species, of which concentrations prevail in the mixture, then the formation of gaseous atomic species by dissociation of previous ones, and, finally, the formation of complex chemical species from the atomic species. A computer program, which permits calculations of equilibrium compositions by the iteration procedure, has been developed. The results of calculations have been compared with data obtained by the programs OPHELIE, MICROPEP, and the program SPP, as documented in the NASA-Lewis Code, which is presently the world-wide standard. All comparisons gave satisfactory agreement.

  10. Exploring the chemical composition of water in the Kandalaksha Bay

    Science.gov (United States)

    Mazukhina, Svetlana; Masloboev, Vladimir; Chudnenko, Konstantin; Khaitov, Vadim; Maksimova, Victoria; Belkina, Natalia

    2014-05-01

    Oil films were noted at the head of the Kandalaksha Bay as far back as in 1971, as soon as the first stage of the oil tank farm had been commissioned (the autumn of 1970). In 1997-1998 there were accidental oil spills posing a real threat to the Kandalaksha Reserve biota. In May 2011, oil spills from the Belomorsk oil tank farm resulted in a local environmental emergency. In this work we have traced the evolution of polluted water by means of hydrogeochemical monitoring and reconstructing the chemical composition of surface and near-bottom water of the Kandalaksha Bay by using physical-chemical modeling (Selector software package, Chudnenko, 2010). The surface and near-bottom water was sampled in the summer of 2012 and 2013 at the following sites: under the numbers 3 (N 67.2.673, E 32.23.753); 4 (N 67.3.349, E 32.28.152); 1 (N 67.5.907, E 32.29.779), and 2 (N 67.6.429, E 32.30.539). The monitored objects and sampling time were sensitive to both the effects of the White Sea water (high tide), fresh water, and water affected by human impact (the oil tank farm). At each site, three samples were taken. The next stage involved reconstructing of the sea water ion composition by modeling within the Al-B-Br-Ar-He-Ne-C-Ca-Cl-F-K-Mg-Mn-N-Na-P-S-Si-Sr-Cu-Zn-H-O-e system, where e is an electron. Modeling of the chemical composition of near-bottom water (site 3) has revealed high contents of carbon dioxide, hydrogen disulphide, hydrocarbonates, and no oxygen (Ehhydrocarbons that might have got to the sampling area in May 2011, or as the result of constant leakage of petroleum hydrocarbons from the oil tank farm. Sampling at site 4 in 2013 has revealed petroleum hydrocarbons both in surface (0.09 mg/l) and near-bottom (0.1 mg/l) water. Both monitoring and modeling have demonstrated that hydrobionts on areas adjoining the oil tank farm are far from prospering. Monitoring should be accompanied by express analysis of oxidizing conditions in both the soil and near-bottom water

  11. Chemical composition of asphaltenes from thermal dissociation of brown coal

    Energy Technology Data Exchange (ETDEWEB)

    Evstaf' ev, S.N.; Denisova, T.I.; Tuturina, V.V.

    1987-07-01

    Investigates chemical composition of asphaltenes and preasphaltenes separated from liquid products of thermal dissociation of Azeisk deposit brown coal in tetralin. Asphaltenes and preasphaltenes represent a mixture of mainly aromatic compounds containing bi- and tri-cyclic aromatic fractions differing by length of aliphatic substituents and by distribution of oxygen-containing functional groups. Describes tests carried out at 300-420 C in autoclaves using 0.1-0.3 mm coal particles and tetralin containing decalin (2.8%) and naphthalene (5.2%). Establishes that asphaltenes soluble in acetone are represented by low-molecular saturated compounds; about 60% of oxygen in asphaltenes and preasphaltenes is attached to ethereal and heterocyclic structure groups. 10 refs.

  12. Chemical methods for the determination of composition of cryolite

    International Nuclear Information System (INIS)

    Preparation of uranium and plutonium alloys containing aluminium involves the use of cryolite and many times, cryolite which may be contaminated with alpha activity has to be analysed for its purity. In view of this, chemical methods for the determination of composition of commercial cryolite samples have been developed. Methods are standardised for the determination of individual constituents of cryolite viz., aluminium, sodium, fluoride and major impurities, calcium and magnesium. Studies on the dissolution of the sample, effect of one or more components on the determination of the other and their elimination are carried out. Aluminium and sodium are determined gravimetrically as oxinate and triple acetate respectively. Fluoride is determined by a volumetric procedure after cation exchange separtion of soluble fluoride. Calcium and magnesium are determined by a sequential pH-metri titration. This report describes the details of the procedures and the results of these studies for two commercial cryolite samples. (author). 7 tabs

  13. Chemical vapor infiltration of TiB{sub 2} composites

    Energy Technology Data Exchange (ETDEWEB)

    Besmann, T.M. [Oak Ridge National Laboratory, TN (United States)

    1995-05-01

    This program is designed to develop a Hall-Heroult aluminum smelting cathode with substantially improved properties. The carbon cathodes in current use require significant anode-to-cathode spacing in order to prevent shorting, causing significant electrical inefficiencies. This is due to the non-wettability of carbon by aluminum which causes instability in the cathodic aluminum pad. It is suggested that a fiber reinforced-TiB{sub 2} matrix composite would have the requisite wettability, strength, strain-to-failure, cost, and lifetime to solve this problem. The approach selected to fabricate such a cathode material is chemical vapor infiltration (CVI). This program is designed to evaluate potential fiber reinforcements, fabricate test specimens, and test the materials in a static bath and lab-scale Hall cell.

  14. Chemical composition of volatile fraction of pakistani peanut and its

    International Nuclear Information System (INIS)

    Arachis hypogaea Linn (peanut or groundnut) is an economically important crop. Thousands of peanut cultivars are grown in the world and studies have been carried out on these but, to the best of our knowledge, no salient work has been done on Pakistani cultivar so far. Here, we report the chemical composition of volatile fraction of Pakistani cultivar of peanut and its anti radical activities using 1,I-Diphenyl-2-picrylhydrazyl radical (DPPH) scavenging and phospho molybdenum complex (PC) method. This study revealed that Pakistani cultivar exhibited an almost equal antioxidant potential to that of standard, butylated hydroxytoluene (BHT), which was obvious from their IC/sub 50/ values. The IC/sub 50/ value of peanut extract was found to be 13.42 +- 26 macro L/mL, relative to butylated hydroxytoluene, having 12.1 +- 0.92 macro/mL. (author)

  15. Rapid chemical vapor infiltration of C/C composites

    Institute of Scientific and Technical Information of China (English)

    ZHANG Ming-yu; WANG Li-ping; HUANG Qi-zhong; CHAI Li-yuan

    2009-01-01

    With liquid petrol gas (LPG) as carbon source,carbon felt as porous perform and hydrogen as diluent,C/C composites were fast fabricated by using a multi-physics field chemical vapor infiltration (MFCVI) process in a self-made furnace.A set of orthogonal experiments were carried out to optimize parameters in terms of indices of density and graphitization degree.The results show the optimal indices can be achieved under the conditions of temperature 650 ℃,LPG concentration 80%,gas flux 60 mL/s,total pressure 20 kPa,infiltration time 15 h.The verification experiment proves the effectiveness of the orthogonal experiments.Under the optimal conditions,the graphitization degree of 75% and bulk density of 1.69 g/cm are achieved with a uniform density distribution.At the same time,a new structure is obtained.

  16. Levels and chemical composition of cotton gin dust.

    Science.gov (United States)

    Wesley, R A; Wall, J H

    1978-12-01

    Dust levels were determined in the three principal work areas of five high-capacity, saw-type cotton gins processing spindle-picked cotton. Dust levels measured by the vertical elutriator, OSHA personal and stationary personal samplers averaged 0.66, 0.96 and 0.87 mg/m3, respectively. Gross chemical analyses of dust samples collected indicated that the composit0n of the dust was highly variable and different for the principal work areas within each gin -- 15 to 53% ash, 2 to 5% moisture, 8 to 18% protein, 19 to 55% cellulose and 8 to 16% water-extractable constituents. Major elements were silicon, potassium, aluminum, calcium and magnesium. PMID:742599

  17. Chemical Composition of Iran's Pistacia atlantica Cold-Pressed Oil

    Directory of Open Access Journals (Sweden)

    M. Saber-Tehrani

    2013-01-01

    Full Text Available The lipid fraction of Pistacia atlantica seeds was extracted for the first time by means of cold-press technique and analyzed for its chemical composition. The fatty acids, sterols, triacylglycerols (TAG, tocopherols, polyphenols, and pigments were identified and their concentrations were determined by means of reversed-phase high-performance liquid chromatography (RP-HPLC and gas chromatography (GC. Because of its high content of unsaturated fatty acids, it might prove to be of value in diets and it may be used as edible cooking or salad oils or for margarine manufacture. Pistacia atlantica seed oil has the unique sterols and tocopherols content providing source of natural antioxidants. The main triacylglycerols were SLL + PLO, SOL + POO, OOLn + PLL, OOO, and SOO. This paper examined the phenolic fraction of Pistacia atlantica seed oil. Moreover, caffeic acid followed by cinnamic acid, pinoresinol, vanillin, p-Coumaric acid, ferulic acid, and o-Coumaric acid was also determined. This paper presents the first investigation of chlorophyll's and carotene's composition in Pistacia atlantica seed oil. Furthermore, pheophytin a was the major component, followed by luteoxanthin, neoxanthin, violaxanthin, lutein, lutein isomers, chlorophyll a, chlorophyll a′, and pheophytin a′ were also determined.

  18. Chemical composition of some wild peanut species (Arachis L.) seeds.

    Science.gov (United States)

    Grosso, N R; Nepote, V; Guzmán, C A

    2000-03-01

    Oil, protein, ash, and carbohydrate contents, iodine value, and fatty acid and sterol compositions were studied in seeds of Arachis trinitensis, A. chiquitana, A. kempff-mercadoi, A. diogoi, A. benensis, A. appressipila, A. valida, A. kretschmeri, A. helodes, A. kuhlmannii, A. williamsii, A. sylvestris, A. matiensis, A. pintoi, A. hoehnei, A. villosa, and A. stenosperma. Oil content was greatest in A.stenosperma (mean value = 51.8%). The protein level was higher in A. sylvestris (30.1%) and A. villosa (29.5%). Mean value of oleic acid varied between 30.6% (A. matiensis) and 46.8% (Arachis villosa), and linoleic acid oscillated between 34.1% (A. villosa) and 47.4% (A. appressipila). The better oleic-to-linoleic (O/L) ratio was exhibited by A. villosa (1.38). Some species showed higher concentration of behenic acid. The greatest level of this fatty acid was found in A. matiensis (6.2%). Iodine value was lower in A. valida (99.2). The sterol composition in the different peanut species showed higher concentration of beta-sitosterol (mean values oscillated between 55.7 and 60.2%) followed by campesterol (12.4-16. 5%), stigmasterol (9.7-13.3%), and Delta(5)-avenasterol (9.7-13.4%). The chemical quality and stability of oils (iodine value and O/L ratio) from wild peanut studied in this work are not better than those of cultivated peanut. PMID:10725154

  19. Physical properties and chemical composition of Segamat Kaolin, Johor, Malaysia

    International Nuclear Information System (INIS)

    Kaolin is a source of secondary mineral as a product of a weathering process of primary minerals. Its main component is fine grain kaolinite (< 2 μm) and it also contains other elements such as aluminium and iron phyllosilicate as the pigment. Aluminium rich kaolin is light in colour with high plasticity and is normally used in the ceramic, plastic, paint, paper, pesticide, pharmacology and cosmetic industries. The physical and chemical characteristics of kaolins are important for its potential application. In this study, about 25 kaolin samples were hand-augered from depths of 1-2 m at Buloh Kasap Segamat, Johor, Malaysia. Chemical analysis carried out included determination of oxides and types of minerals by X-ray diffraction and X-ray fluorescence. Shrinkage rate, rupture modulus and water absorption rate tests were carried out in the physical properties analysis. Plastic and liquid limits of the kaolin were also measured for plastic index. The Segamat kaolin was light in colour due to its high silicate composition. The highest mineral content in the kaolin was kaolinite and quartz occurred as impurities. The low shrinkage rate showed that the kaolin was dense with little voids, hence very suitable for use in the ceramic industry. This kaolin has low water absorption, plasticity and durable according to the rupture modulus test. (author)

  20. 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)

  1. Chemical Composition and Antioxidant Capacity of Three Plum Cultivars

    Directory of Open Access Journals (Sweden)

    Sandra Voća

    2009-12-01

    Full Text Available The aim of this study was to determine the chemical composition and antioxidants capacity of three plum cultivars, namely ‘Top’, ‘Elena’ and ‘Bistrica’. Fruits were harvested and following parameters were determined: dry matter, total acids (TA, total soluble solids (TSS, pH, vitamin C, total phenols, nonflavonoids and antioxidant capacity. Differences between cultivars for most of the chemical parameters were observed. The cultivar ‘Bistrica’ showed higher values of dry matter, TSS, vitamin C and pH value, while ‘Top’ had higher total acids value and lowest TSS, dry matter, vitamin C and pH. Total phenolics content varied from 157.70 mg in ‘Elena’ to 344.10 mg in ‘Bistrica’, expressed as gallic acid equivalents (GAE, on fresh weight basis. ‘Top’ contains the highest amount of non-flavonoids among cultivars studied. Therefore, ‘Bistrica’ and ‘Top’ show the highest antioxidant capacity, as well. There were significant differences between total phenolics and non-flavonoids content between ‘Elena’ and other two cultivars, while antioxidant capacity showed no significant difference (p ≤ 0.05. Total antioxidant capacity of fruits ranged from 3.10 mmol/kg in ‘Elena’ to 3.17 mmol/kg in ‘Top’ and ‘Bistrica’.

  2. A New Mathematical Formulation of the Governing Equations for the Chemical Compositional Simulation

    CERN Document Server

    Bekbauov, Bakhbergen E; Berdyshev, Abdumauvlen

    2015-01-01

    It is the purpose of this work to develop new approach for chemical compositional reservoir simulation, which may be regarded as a sequential method. The development process can be roughly divided into the following two stages: (1) development of a new mathematical formulation for the sequential chemical compositional reservoir simulation, (2) implementation of a sequential solution approach for chemical compositional reservoir simulation based on the formulation described in this paper. This paper addresses the first stage of the development process by presenting a new mathematical formulation of the chemical compositional reservoir flow equations for the sequential simulation. The newly developed mathematical formulation is extended from the model formulation used in existing chemical compositional simulators. During the model development process, it was discovered that the currently used chemical compositional model estimates the adsorption effect on the transport of a component reasonably well but it viol...

  3. The chemical composition of the Orion star forming region: stars, gas and dust

    CERN Document Server

    Simón-Díaz, S; Przybilla, N; Stasińska, G

    2010-01-01

    We present a summary of main results from the studies performed in the series of papers "The chemical composition of the Orion star forming region". We reinvestigate the chemical composition of B-type stars in the Orion OB1 association by means of state-of-the-art stellar atmosphere codes, atomic models and techniques, and compare the resulting abundances with those obtained from the emission line spectra of the Orion nebula (M42), and recent determinations of the Solar chemical composition.

  4. Chemical composition of sediments from White Sea, Russian Arctic

    Science.gov (United States)

    Gamza, Olga; Shevchenko, Vladimir; Novigatsky, Aleksandr

    2010-05-01

    The White Sea, the only Russian inland sea, is located on the north of outlying districts of the European part of Russia, belongs to Arctic Ocean. Area of water of sea occupies about 90 tousend square kilometers. The sea can be divided into some general parts: neck, funnel, basin and 4 Bays: Dvina Bay, Kandalaksha Bay, Mezen Bay and Onega Bay. The purpose of this work was geochemical mapping of the surface sediments of this area. The main tasks were: compilation data base of element composition of the surface sediments, geochemical mapping of each element, research of the anormal concentration of elements on the surface. To detect the content of chemical elements several methods were used: atomic absorption spectrometry (P.P. Shirshov Institute of Oceanology); neutron activation analysis (Vernadsky Institute of Geochemistry and Analytical Chemistry), total and organic carbon analysis, photometric method to detection Si, Al, P (P.P. Shirshov Institute of Oceanology). Bulk composition is one of the fundamental characteristics of sediments and bottom deposites of modern basins. Coarse-grained sediments with portion of pelitic component 80%). Character of elements distribution correlates with facial distribution of sediments from White Sea. According to litologic description, bottom surface of Dvina Bay is practically everywhere covered by layer of fine-grained sand. In the border area between Dvina Bay and White Sea basin on terraced subwater slope aleurite politic silts are abundant. They tend to exhange down the slope to clay silts. In Onega Bay fractions of non-deposition are observed. They are characterized by wide spread of thin blanket poorgraded sediments, which are likely to be relic. Relief of Kandalakscha Bay bottom is presented as alternation of abyssal fosses (near 300 m) with silles and elevations (depressions and in central part of the sea, which is quite wide from both places of original sedimentation and run off sources [2]. Thus, the interrelation

  5. Vector diagram of the chemical compositions of tektites and earth lavas

    Science.gov (United States)

    Kvasha, L. G.; Gorshkov, G. S.

    1978-01-01

    The chemical compositions of tektites and various volcanic glasses, similar in composition to tektites are compared by a petrochemical method. The advantage of the method is that a large number of chemical analyses of igneous rocks can be graphically compared with the help of vectors, plotted in relation to six parameters. These parameters, calculated from ratios of the main oxides given by silicate analysis, reflect the chief characteristics of igneous rock. Material for the study was suppled by data from chemical analysis characterizing tektites of all known locations and data from chemical analyses of obsidians similar in chemical composition to tektites of various petrographical provinces.

  6. Chemical and isotopic composition of precipitations in Syria

    International Nuclear Information System (INIS)

    The objective of this study is to determine isotopic characteristics of precipitation, the climatic and geographical conditions affecting isotopic composition in order to obtain the input function of groundwater to evaluate the water resources.13 meteoric stations were selected in Syria for cumulative monthly rainfall sampling during two hydrological cycles; 1991-1992 and 1992-1993. The chemical and isotopic compositions of monthly precipitation were studied. The winter and spring rainfall isotopic characteristics were determined, in addition to the Syrian meteoric line (SMWL) was estimated with a slope of 6.62 and that of both Syria and Jordan of 6.73. The effect of climatic factors as temperature and relative air humidity on oxygen-18, deuterium and d-excess were studied and it was found that the relationship between temperature and oxygen-18 and deuterium is a positive linear correlation; however, it is a negative correlation with d-excess. The mean seasonal variation amplitude of 18O was about 6%, and the amount effect on isotopic content of precipitation was studied. The geographic factors and its affect on isotopic contents of precipitation such as altitude were considered, furthermore, the isotopic gradient with altitude was determined for both oxygen-18 and deuterium (-0.14 % and -0.84% /100m respectively). The spatial distribution of oxygen-18, deuterium, tritium and d-excess indicted the effect of mountain chains and gaps between mountains on the isotopic content, the continental effect on tritium build-up by about 33% per 100 Km from the coast. The increase of d-excess values towards the south west proves the eastern Mediterranean climate type over this region.(author)

  7. Chemical Composition of Urban Street Sediments and Its Sources

    Institute of Scientific and Technical Information of China (English)

    Cen Kuang; Hou Min; Thomas Neumann; Stefan Norra; Doris Stüben

    2004-01-01

    The distribution and the concentrations of various chemical elements in street sediments were investigated along a rural-urban boundary in Beijing, China. The statistical factor analysis of the data concerned identifies two anthropogenic sources responsible for the contamination of Beijing air. The first source is a steel factory in the western part of Beijing. From this source, Mn, Fe and Ti were emitted into the atmosphere through chimneys and by wind from coal heaps used as the primary energy source for the factory. The second source is a combination of traffic, domestic heating and some small factories in the center of Beijing urban area discharging Cu, Pb, Zn and Sn. Grain-size analyses show that most of the metals in the road dust have higher concentrations in the small grain-size fraction <0.125 mm, which is the severest case because these small particles with larger specific surface area and high heavy metal contents fly up easily and float in the air for a long time. Besides the anthropogenic contamination, such elements as Y, Zr, Nb, Ce and Rb are derived mainly both from natural soils and from the deserts. This is supported by mineral-phase analysis, which shows a clear imprint of materials in road dusts coming from the west China deserts. Our results clearly show that the chemical compositions of the urban road dusts can be used to identify distinctive sources responsible for the contamination mentioned above. The study shows that the chemistry of road dusts is an important monitor to assess the contamination in the urban environment.

  8. Chemical Composition, Antifungal and Insecticidal Activities of Hedychium Essential Oils

    Directory of Open Access Journals (Sweden)

    Kanniah Rajasekaran

    2013-04-01

    Full Text Available The antimicrobial properties of essential oils have been documented, and their use as “biocides” is gaining popularity. The aims of this study were to analyze the chemical composition and assess the biological activities of Hedychium essential oils. Oils from 19 Hedychium species and cultivars were analyzed by gas chromatography (GC and gas chromatography-mass spectrometry (GC-MS techniques. The antifungal and insecticidal activities of these oils were tested against Colletotrichum acutatum, C. fragariae, and C. gloeosporioides, and three insects, the azalea lace bug (Stephanitis pyrioides, the yellow fever mosquito (Aedes aegypti, and the red imported fire ant (Solenopsis invicta. Hedychium oils were rich in monoterpenes and sesquiterpenes, especially 1,8-cineole (0.1%–42%, linalool (<0.1%–56%, a-pinene (3%–17%, b-pinene (4%–31%, and (E-nerolidol (0.1%–20%. Hedychium oils had no antifungal effect on C. gloeosporioides, C. fragariae, and C. acutatum, but most Hedychium oils effectively killed azalea lace bugs. The oils also show promise as an adult mosquito repellent, but they would make rather poor larvicides or adulticides for mosquito control. Hedychium oils acted either as a fire ant repellent or attractant, depending on plant genotype and oil concentration.

  9. Chemical compositions of two different Thymus species essential oils

    Directory of Open Access Journals (Sweden)

    Samira Jaberi

    2015-06-01

    Full Text Available Thymus is one of the most important members of Lamiaceae family. Aerial parts of the plant have been widely used in medicine. It has been reported that most of these effects are related to phenolic compounds especially thymol and carvacrol in Thymus essential oil. In this study, aerial parts of Thymus daenensis and Thymus lancifolius were collected from Kohgiluyeh and Boyer-Ahmad, Iran. Essential oils of aerial parts of these plants were gained by the hydrodistillation method and the chemical compositions were analyzed by gas chromatography/ Mass spectrometry (GC/MS. The major components of the essential oil of T. daenensis were thymol (39.91%, carvacrol (29.93%, linalool (5.55%, caryophyllene (3.5% and geraniol (3.09%, whereas the major components of the essential oil of T. lancifolius were: carvacrol (25.55%, thymol (20.79%, linalool (16.8%, α-terpineol (6.34%, borneol (4.00%, caryophyllene (3.98%, p-cymene (3.38% and cis-linalool oxide (3.21%. Linalool was reported as another major component in T. lancifolius

  10. Tea tree oil: contact allergy and chemical composition.

    Science.gov (United States)

    de Groot, Anton C; Schmidt, Erich

    2016-09-01

    In this article, contact allergy to, and the chemical composition of, tea tree oil (TTO) are reviewed. This essential oil is a popular remedy for many skin diseases, and may be used as neat oil or be present in cosmetics, topical pharmaceuticals and household products. Of all essential oils, TTO has caused most (published) allergic reactions since the first cases were reported in 1991. In routine testing, prevalences of positive patch test reactions have ranged from 0.1% to 3.5%. Nearly 100 allergic patients have been described in case reports and case series. The major constituents of commercial TTO are terpinen-4-ol, γ-terpinene, 1,8-cineole, α-terpinene, α-terpineol, p-cymene, and α-pinene. Fresh TTO is a weak to moderate sensitizer, but oxidation increases its allergenic potency. The major sensitizers appear to be ascaridole, terpinolene, α-terpinene, 1,2,4-trihydroxymenthane, α-phellandrene, and limonene. The clinical picture of allergic contact dermatitis caused by TTO depends on the products used. Most reactions are caused by the application of pure oil; cosmetics are the culprits in a minority of cases. Patch testing may be performed with 5% oxidized TTO. Co-reactivity to turpentine oil is frequent, and there is an overrepresentation of reactions to fragrance mix I, Myroxylon pereirae, colophonium, and other essential oils. PMID:27173437

  11. Calorimetry, chemical composition and in vitro digestibility of oilseeds.

    Science.gov (United States)

    Ítavo, Luís Carlos Vinhas; Soares, Cláudia Muniz; Ítavo, Camila Celeste Brandão Ferreira; Dias, Alexandre Menezes; Petit, Hélène Veronique; Leal, Eduardo Souza; de Souza, Anderson Dias Vieira

    2015-10-15

    The objective of the study was to determine the quality of sunflower, soybean, crambe, radish forage and physic nut, by measuring chemical composition, in vitro digestibility and kinetics of thermal decomposition processes of mass loss and heat flow. Lipid was inversely correlated with protein of whole seed (R = -0.67), meal (R = -0.95), and press cake (R = -0.78), and positively correlated with the enthalpy (ΔH) of whole seed. Soybean seed and meal presented a high in vitro digestibility but poor energy sources with ΔH averaging 5907.5 J/g and 2570.1J/g for whole seed and meal, respectively. As suggested by the release of heat, measured by ΔH, whole seeds of crambe (6295.1J/g), radish forage (6182.7 J/g), and physic nut (6420.0 J/g) may be potential energy sources for ruminant animals. The thermal analysis provided additional information besides that obtained from the usual wet chemistry and in vitro measurements. PMID:25952861

  12. Chemical composition dependence of exposure buildup factors for some polymers

    Energy Technology Data Exchange (ETDEWEB)

    Singh, Tejbir [Department of Physics, S.D.D.I.E.T., Barwala, District Panchkula, Haryana 134 118 (India)], E-mail: tejbir.s@rediffmail.com; Kumar, Naresh [Department of Physics, Lovely Professional University, Phagwara 144 402 (India)], E-mail: naresh20dhiman@yahoo.com; Singh, Parjit S. [Department of Physics, Punjabi University, Patiala 147 002 (India)], E-mail: dr_parjit@hotmail.com

    2009-01-15

    Exposure buildup factors for some polymers such as poly-acrylo-nitrile (PAN), poly-methyl-acrylate (PMA), poly-vinyl-chloride (PVC), synthetic rubber (SR), tetra-fluro-ethylene (Teflon) have been computed using the G.P. fitting method in the energy range of 0.015-15.0 MeV, up to the penetration of 40 mean free paths (mfp). The variation of exposure buildup factors for all the selected polymers with incident photon energy at the fixed penetration depths has been studied, mainly emphasizing on chemical composition (equivalent atomic number) of the selected polymers. It has been observed that for the lower penetration depths (below 10 mfp), the exposure buildup factor decreases with the increase in equivalent atomic number of the selected polymers at all the incident photon energies. However, at the penetration depth of 10 mfp and incident photon energy above 3 MeV, the exposure buildup factor becomes almost independent of the equivalent atomic number of the selected polymers. Further, above the fixed penetration depth of 15 mfp of the selected polymers and above the incident photon energy of 3 MeV, reversal in the trend has been observed, i.e., the exposure buildup factor increases with the increase in equivalent atomic number.

  13. Chemical and isotopic composition of precipitations in Syria

    International Nuclear Information System (INIS)

    13 meteoric stations were selected in syria for cumulative monthly rainfall sampling during two hydrological cycles; 1991-1992 and 1992-1993. The chemical and isotopic compositions of monthly precipitation were studied. The winter and spring rainfall isotopic characteristics were determined, in addition to the syrian or local meteoric line (SMWL) was estimated with a slope of 6.63 and that of both syria and Jordan of 6.73. The effect of climatic factors as temperature and relative air humidity on oxygen-18, deuterium and d-excess were studied and it was found that the relationship between temperature and oxygen-18 and deuterium is a positive linear correlation; however, it is a negative correlation with d-excess. The mean seasonal variation amplitude was determined by 6%, and the amount effect on isotopic content of precipitation was studied. The geographic factors and its affect on isotopic contents of precipitation such as altitude were considered, furthermore, the isotopic gradient with altitude was determined for both oxygen-18 and deuterium (-0.14% and - 0.84%/100 m elevation respectively). The spatial variability of oxygen-18, deuterium, tritium and d-excess indicted the effect of mountain chains and gaps between mountains on the isotopic content of precipitation, the continental effect on tritium build-up by about 33% per 100 Km from the coast. The increase of d-excess values towards the south west proves the eastern mediterranean climate type over this region. (author)

  14. Brazilian kefir: structure, microbial communities and chemical composition

    Directory of Open Access Journals (Sweden)

    Karina Teixeira Magalhães

    2011-06-01

    Full Text Available Microbial ecology and chemical composition of Brazilian kefir beverage was performed. The microorganisms associated with Brazilian kefir were investigated using a combination of phenotypic and genotypic methods. A total of 359 microbial isolates were identified. Lactic acid bacteria (60.5% were the major isolated group identified, followed by yeasts (30.6% and acetic acid bacteria (8.9%. Lactobacillus paracasei (89 isolates, Lactobacillus parabuchneri (41 isolates, Lactobacillus casei (32 isolates, Lactobacillus kefiri (31 isolates, Lactococcus lactis (24 isolates, Acetobacter lovaniensis (32 isolates, Kluyveromyces lactis (31 isolates, Kazachstania aerobia (23 isolates, Saccharomyces cerevisiae (41 isolates and Lachancea meyersii (15 isolates were the microbial species isolated. Scanning electron microscopy showed that the microbiota was dominated by bacilli (short and curved long cells growing in close association with lemon-shaped yeasts cells. During the 24 h of fermentation, the protein content increased, while lactose and fat content decreased. The concentration of lactic acid ranged from 1.4 to 17.4 mg/ml, and that of acetic acid increased from 2.1 to 2.73 mg/ml. The production of ethanol was limited, reaching a final mean value of 0.5 mg/ml.

  15. Microbial population, chemical composition and silage fermentation of cassava residues.

    Science.gov (United States)

    Napasirth, Viengsakoun; Napasirth, Pattaya; Sulinthone, Tue; Phommachanh, Kham; Cai, Yimin

    2015-09-01

    In order to effectively use the cassava (Manihot esculenta Crantz) residues, including cassava leaves, peel and pulp for livestock diets, the chemical and microbiological composition, silage preparation and the effects of lactic acid bacteria (LAB) inoculants on silage fermentation of cassava residues were studied. These residues contained 10(4) to 10(5) LAB and yeasts, 10(3) to 10(4) coliform bacteria and 10(4) aerobic bacteria in colony forming units (cfu) on a fresh matter (FM) basis. The molds were consistently at or below the detectable level (10(2) cfu of FM) in three kinds of cassava residues. Dry matter (DM), crude protein (CP) and neutral detergent fiber (NDF) content of cassava residues were 17.50-30.95%, 1.30-16.41% and 25.40-52.90% on a DM basis, respectively. The silage treatments were designed as control silage without additive (CO) or with LAB inoculants Chikuso-1 (CH, Lactobacillus plantarum) and Snow Lacto (SN, Lactobacillus rhamnosus) at a rate of 5 mg/kg of FM basis. All silages were well preserved with a low pH (below 4.0) value and when cassava residues silage treated with inoculants CH and SN improved fermentation quality with a lower pH, butyric acid and higher lactic acid than control silage. PMID:25781881

  16. Physico-chemical properties of Brazilian cocoa butter and industrial blends. Part I Chemical composition, solid fat content and consistency

    OpenAIRE

    Ribeiro, A. P. B.; Claro da Silva, R.; Gioielli, L. A.; de Almeida Gonçalves, M. I.; Grimaldi, R.; Gonçalves, L. A.G.; Guenter Kieckbusch, T.

    2012-01-01

    A comparative study of the primary properties of six cocoa butter samples, representative of industrial blends and cocoa butter extracted from fruits cultivated in different geographical areas in Brazil is presented. The samples were evaluated according to fatty acid composition, triacylglycerol composition, regiospecific distribution, melting point, solid fat content and consistency. The results allowed for differentiating the samples according to their chemical compositions, thermal resista...

  17. Rainwater chemical composition at two sites in Central Mexico

    Science.gov (United States)

    Báez, A. P.; Belmont, R. D.; García, R. M.; Torres, M. C. B.; Padilla, H. G.

    2006-04-01

    Chemical analyses were performed on rainwater samples collected at the National Autonomous University of Mexico (UNAM) in Mexico City and at a wooded site, Rancho Viejo (RV) in the State of Mexico, for the periods 1994-2000 and 1994-1999, respectively. At UNAM, rainwater was collected for the entire rainy season period each year, while at RV, technical considerations limited collection to weekends only. The results showed large variations in rainwater chemical composition in most years, mainly because of the variability of meteorological conditions and also because of changes in source emissions. Sulfates and NH 4+ showed higher annual volume-weighted mean concentrations (VWMC) in both sites. At UNAM, the maximum annual VWMC for SO 42- occurred in March and the minimum in July and August. Lower concentrations of almost all ions were found at RV; however, the H + concentration was higher at this site. The pH in Mexico City, calculated from the annual VWMC of H +, was 4.95, which is a little higher than pH values reported in some other countries. Despite the fact that sulfate and NO 3- concentrations were lower at RV, the pH was lower. Air-mass back trajectories were calculated for individual concentrations of SO 42-, H +, NH 4+, Ca 2+, and Mg 2+, observed at each sampling site for weekend data. At RV, sulfate concentrations were higher when air-mass back trajectories indicated a wind flow from Mexico City and Toluca at 1000 MAGL (meters above ground level) and 3000 MAGL. The hydrogen ion exhibited the same behavior. Calcium and Mg 2+ concentrations were also higher when the wind blew from urban areas at 1000 and 3000 MAGL. At UNAM, H + concentration was lower and Ca 2+ and Mg 2+ were higher when wind blew from the northern sector of the city at 1000 and 3000 MAGL. In UNAM, the NO 3-/SO 42- and NH 4+/SO 42- ratios were 0.5 and 1.09 in 1994 and 0.86 and 1.64 in 2000, respectively, indicating a decrease in SO 2 emissions resulting from the change of fuel oil to gas

  18. Leaching properties and chemical compositions of calcines produced at the Idaho Chemical Processing Plant

    International Nuclear Information System (INIS)

    No significant chemical differences were determined between retrieved and fresh calcine based on chemical and spectrochemical analyses. Little can be derived from the amounts of the radioisotopes present in the retrieved calcine samples other than the ratios of strontium-90 to cesium-137 are typical of aged fission product. The variations in concentrations of radionuclides within the composite samples of each bin also reflect the differences in compositions of waste solutions calcined. In general the leaching characteristics of both calcines by distilled water are similar. In both materials the radionuclides of cesium and strontium were selectively leached at significant rates, although cesium leached much more completely from the alumina calcine than from the zirconia calcine. Cesium and strontium are probably contained in both calcines as nitrate salts and also as fluoride salts in zirconia calcine, all of which are at least slightly soluble in water. Radionuclides of cerium, ruthenium, and plutonium in both calcines were highly resistant to leaching and leached at rates similar to or less than those of the matrix elements. These elements exist as polyvalent metal ions in the waste solutions before calcination and they probably form insoluble oxides and fluorides in the calcine. The relatively slow leaching of nitrate ion from zirconia calcine and radiocesium from both calcines suggests that the calcine matrix in some manner prevents complete or immediate contact of the soluble ions with water. Whether radiostrontium forms slightly fluoride salts or forms nitrate salts which are protected in the same manner as radiocesium is unknown. Nevertheless, selective leaching of cesium and strontim is retarded in some manner by the calcine matrix

  19. Quantification of aerosol chemical composition using continuous single particle measurements

    Directory of Open Access Journals (Sweden)

    C.-H. Jeong

    2011-07-01

    Full Text Available Mass concentrations of sulphate, nitrate, ammonium, organic carbon (OC, elemental carbon (EC were determined from real time single particle data in the size range 0.1–3.0 μm measured by an Aerosol Time-of-Flight Mass Spectrometer (ATOFMS at urban and rural sites in Canada. To quantify chemical species within individual particles measured by an ATOFMS, ion peak intensity of m/z −97 for sulphate, −62 for nitrate, +18 for ammonium, +43 for OC, and +36 for EC were scaled using the number and size distribution data by an Aerodynamic Particle Sizer (APS and a Fast Mobility Particle Sizer (FMPS. Hourly quantified chemical species from ATOFMS single-particle analysis were compared with collocated fine particulate matter (aerodynamic diameter < 2.5 μm, PM2.5 chemical composition measurements by an Aerosol Mass Spectrometer (AMS at a rural site, a Gas-Particle Ion Chromatograph (GPIC at an urban site, and a Sunset Lab field OCEC analyzer at both sites. The highest correlation was found for nitrate, with correlation coefficients (Pearson r of 0.89 (ATOFMS vs. GPIC and 0.85 (ATOFMS vs. AMS. ATOFMS mass calibration factors, determined for the urban site, were used to calculate mass concentrations of the major PM2.5 chemical components at the rural site near the US border in southern Ontario. Mass reconstruction using the ATOFMS mass calibration factors agreed very well with the PM2.5 mass concentrations measured by a Tapered Element Oscillating Microbalance (TEOM, r = 0.86 at the urban site and a light scattering monitor (DustTrak, r = 0.87 at the rural site. In the urban area nitrate was the largest contributor to PM2.5 mass in the winter, while organics and sulphate contributed ~64 % of the summer PM2.5 in the rural area, suggesting a strong influence of regional/trans-boundary pollution. The mass concentrations of five major species in ten size-resolved particle

  20. 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.

  1. 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...

  2. Study on Physical Properties and Chemical Composition of Some Myanmar Gems

    International Nuclear Information System (INIS)

    Physical properties of some Myanmar gems were studied by using refractometer, dichroscope, polariscope, SG test, UV test and microscope. Then, chemical composition were investigated by XRF-technique. After that, gem identification, evaluation, colour improvement were studied according to these physical properties and chemical composition

  3. Seminar for hydrocarbon detection with composite geophysical/geo-chemical techniques

    Institute of Scientific and Technical Information of China (English)

    2005-01-01

    “Seminar for hydrocarbon detection with composite geophy sical/geo-chemical techniques”,jointly organized by China petroleum Exploration & Production Company and Exploration Geophysical Committee of CGS and supported by the Composite Geophysical/geo-chemical Departement of Oriental Geophysical Company and China Exploration&Development Research Instiute,

  4. Characteristics and chemical composition of ground water in Bara basin

    International Nuclear Information System (INIS)

    In this study analysis was carried for forty five ground water samples from different areas within Bara basin, fifteen solid samples, three locally produced salt samples and one mixed rocks sample. The rocks were brought from the underground during hand digging of wells. The study include areas Um-Galgie, Bara, Saatah Shambool, Um-Sadoun El-Shareef, EI-Dair, EI-Murra, Taybah, Um-sadoun EI-Nazir, EI-Hodied Shareef, Um-Nabeg, Um-Gazira, Magror, Ma'afa, El-Kheiran, Dameerat Abdu, Sharshar East, Sharshar West, El-Gaa'a Um-Safari, and El-Gaa'a Um EL-Gora. Physical characteristics of ground water samples were determined including pH, electrical conductivity, turbidity, and total dissolved solids, using pH-meter, conductivity-meter, and ultra- meter. Many other analytical techniques were used. Spectrophotometric analysis was used for determination of nitrate(NO3''-''-), nitrite (No2''-), ammonia-nitrogen (NH3-N), fluoride(F), sulphide(S''-''-) and sulphate(SO4''-''-) ions. Chloride (Cl''-) and total alkalinity(OH''-,CO3''-''-,HCO3''-) were determined titrametrically. X-ray diffraction technique was used for determination of chemical composition of solid samples (soils,salts and rocks). X-ray fluorescence technique was used to measure the concentration of some metals in the solid samples. Radioactivity was measured using gamma-spectrometry. Atomic absorption spectrometry was used for the measurement of cations concentration in ground water samples as well as soil samples, this include macro-cations: sodium (Na), potassium (K), calcium (Ca), magnesium (Mg) and micro cations (trace): Iron (Fe), manganese (Mn), chromium (Cr), cobalt (Co), nickel (Ni), copper (Cu), zinc (Zn), cadmium (Cd), silver (Ag), lead (Pb) and barium (Ba). The results obtained were statistically treated, using SPSS program, discussed and further future research was suggested. The analysis show general suitability of fresh ground water at section A and C samples from physical and chemical characteristic

  5. Chemical composition of buckwheat plant parts and selected buckwheat products

    Directory of Open Access Journals (Sweden)

    Petra Vojtíšková

    2014-11-01

    Full Text Available Chemical composition plant parts (roots, stalks, leaves, blossoms of common buckwheat (Fagopyrum esculentum Moench and selected products made from its seeds (peels, whole seed, wholemeal flour, broken seeds, crunchy products Natural and Cocoa, flour, and pasta was determined. Samples were dried and ground to a fine powder. All analyses were performed according to the Commission Regulation no. 152/2009, while rutin concentration was determined by the modified HPLC method. The lowest content of moisture was found in roots (4.3% and in peels (almost 8% and the highest moisture (nearly 11% was discovered in seeds. The lowest amount of crude protein (3.5% was found in peels, the highest crude protein amount (>13% in both flours and leaves (23%. The starch content (>50% in dry matter differs from one sample to another. Only in peels the content of starch was about 3.5%. From all examined samples, the lowest content of fat was found in crunchy products Cocoa, 1.7%. The lowest amount of histidine was determined in all studied samples, except peels, the highest content of glutamic acid was determined in almost all samples, except peels. Whole-meal flour is very rich source of Ca and Fe. The content of these elements was 1172 mg.kg-1 and 45.9 mg.kg-1, respectively. On the other hand, the highest content of Pb (>1 mg.kg-1 was found in broken seeds. The greatest concentration of rutin was determined in blossoms and leaves (83.6 and 69.9 mg.g-1, respectively. On the other hand, the lowest concentrations of rutin were found in buckwheat products (generally less then 1 mg.g-1, i.e. in wholemeal flour, 702 μg.kg-1, the lowest almost 10 μg.kg-1 in pasta.

  6. Chemical composition and shape of snow crystals in Antarctica

    International Nuclear Information System (INIS)

    Fresh snow samples collected in a coastal Antarctic site (Terra Nova Bay) were examined by considering both the chemical composition and ice crystal shape. Measured concentrations in snow samples show that nucleation is the dominant aerosol scavenging process. An additional contribution from phoretic forces to aerosol scavenging during growth of ice crystals can be deduced from the correlation between non sea-salt sulphate (nss-SO42-) and methanesulfonic acid (MSA) measured in snow samples. The sea-salt contribution is dominant, as usually observed in the coastal Antarctic stations. By determining sea-salt from Na+ concentration, the values of 4400 μg l-1; 2400 μgl-1; 2900 μgl-1; 650 μgl-1 were obtained for the examined samples. The NO3-/Na+ ratio in fresh snow (range 0.1-0.6), much higher than the value in sea-water (about 10-4), excludes a marine origin for NO3- ion, suggesting a continental and/or stratospheric source. Organic compounds (propionate, acetate, formate, MSA and glycolate) were in addition measured in snow samples. Ice crystal replicas were made by collecting crystals on microscope slides, previously covered with a thin layer of 2% formvar in chloroform. Samples were analyzed by a scanning electron microscope (SEM). A large variety of ice crystal habits (needles, hexagonal plates, crystals with branches, dendritic crystals, etc.) were observed. In the examined replicas of different events, cases are noted in which simple plates are prevalent, others in which prevalently complex crystal shapes are observed, and others again in which simple and complex crystal shapes are present simultaneously.

  7. Surface of Lactic Acid Bacteria: Relationships between Chemical Composition and Physicochemical Properties

    OpenAIRE

    Boonaert, C J; Rouxhet, Paul

    2000-01-01

    The surface chemical composition and physicochemical properties (hydrophobicity and zeta potential) of two lactic acid bacteria, Lactococcus lactis subsp. lactis bv. diacetilactis and Lactobacillus helveticus, have been investigated using cells harvested in exponential or stationary growth phase. The surface composition determined by X-ray photoelectron spectroscopy (XPS) was converted into a molecular composition in terms of proteins, polysaccharides, and hydrocarbonlike compounds. The conce...

  8. Vegetation change impacts on soil organic carbon chemical composition in subtropical forests.

    Science.gov (United States)

    Guo, Xiaoping; Meng, Miaojing; Zhang, Jinchi; Chen, Han Y H

    2016-01-01

    Changes in the chemical composition of soil organic carbon (SOC) might strongly affect the global carbon cycle as it controls the SOC decomposition rate. Vegetation change associated with long-term land use changes is known to strongly impact the chemical composition of SOC; however, data on the impacts of vegetation change following disturbance events of short durations and succession that occur frequently in forest ecosystems via diverse management objectives on SOC chemical composition are negligible. Here we examined the impacts of vegetation changes on the chemical composition of SOC by sampling soils of native broad-leaved forests, planted mixed broad-leaved and coniferous forests, and tea gardens in eastern China. We used nuclear magnetic resonance spectroscopy to quantify SOC chemical composition. We found that among all components of SOC chemical composition, alkyl carbon (C) and aryl C were more liable to change with vegetation than other SOC components. Soil pH was negatively correlated to the relative abundances of alkyl C and N-alkyl C, and Shannon's index of overstory plant species was positively correlated to the relative abundances of phenolic C and aromaticity. Our results suggest that vegetation changes following short disturbance events and succession may strongly alter SOC chemical composition in forest ecosystems. PMID:27403714

  9. Designing of the chemical composition of steels basing on the hardenability of constructional steels

    International Nuclear Information System (INIS)

    The paper presents the original method of modelling of the relationships between chemical composition of alloy constructional steel and its hardenability, employing neural networks. Basing on the experimental results of the hardenability investigations, which employed Jominy method, the model of the neural networks was developed and fully verified experimentally. The model makes it possible to obtain Jominy hardenability curves basing on the steel chemical composition. The model of neural networks, making it possible to design the steel chemical composition, basing on the known Jominy hardenability curve shape, was developed also and fully verified numerically. (author)

  10. Chemical composition of nanomodified composite binder with nano- and microsized barium silicate

    Directory of Open Access Journals (Sweden)

    KOROLEV Evgenij Valerjevich

    2014-08-01

    Full Text Available There are several possibilities to improve cement-based binders. In particular, many properties of cement stone can be enhanced by means of micro- and nanoscale modification. In a number of previous works we had shown that application of barium hydrosilicates leads to such improvement. The present article is devoted to the investigation of the chemical composition of the cement stone which is modified by means of addition of barium hydrosilicates. The modification was performed on different scales: micro- and nanoscale; the results of simultaneous multi-scale modification are also presented. The examination was carried out with help of different modern research techniques – FT IR spectroscopy, differential thermal analysis and X-ray phase analysis. Identification of the new phases and comparative quantitative assessment of their content are performed. It is found that the use of nano- and micro-sized barium hydrosilicates as additives leads to reduction of portlandite by 27...28%; by means of multi-scale modification it is possible to reduce the content of portlandite much more (by 83.3%. Due to addition of nano- and micro-sized barium-based modifiers both the amount of calcium hydrosilicates in reaction products is enlarged, and structure of the mentioned hydrosilicates is changed (the formation of a fine-grained structure of hydration products takes place. Micro-sized barium hydrosilicates are chemically active additives and promote the formation of an additional quantity of calcium hydrosilicates of type CSH (I. The use of nanoscale barium hydrosilicates promotes the formation of CSH (I and CSH (II calcium hydrosilicates, and also both riversidite and xonotlite. As a result of simultaneous application of nano- and micro-sized barium hydrosilicates the content of CSH (II increases. This can be confirmed by means of differential thermal and X-ray analysis. The amount of CSH (I, riversidite and various tobermorites is also increases. It is

  11. Areca Fiber Reinforced Epoxy Composites: Effect of Chemical Treatments on Impact Strength

    Directory of Open Access Journals (Sweden)

    S. Dhanalakshmi

    2015-06-01

    Full Text Available In this research work, impact strength of untreated, alkali treated, potassium permanganate treated, benzoyl chloride treated and acrylic acid treated areca fiber reinforced epoxy composites were studied under 40%, 50%, 60% and 70% fiber loadings. Impact strength increased with increase in fiber loading up to 60% and then showed a decline for all untreated and chemically treated areca fiber reinforced epoxy composites. The acrylic acid treated areca fiber reinforced epoxy composites with 60% fiber loading showed highest impact strength of 28.28 J/mm2 amongst all untreated and chemically treated areca/epoxy composites with same 60% fiber loading.

  12. Level and Chemical Composition of Cryoglobulins in Schizophrenia

    Science.gov (United States)

    Khoyetsyan, Aren; Boyajyan, Anna; Melkumova, Maya

    The blood samples of 40 schizophrenic patients were tested for the presence of cryoglobulins (Cgs) and composition of Cgs was examined. The elevated levels of type III Cgs, containing complement components, were detected in all study subjects.

  13. Chemically and Thermally Stable High Energy Density Silicone Composites Project

    Data.gov (United States)

    National Aeronautics and Space Administration — Thermal energy storage systems with 300 ? 1000 kJ/kg energy density through either phase changes or chemical heat absorption are sought by NASA. This proposed...

  14. Variation in size, morphology and chemical composition of polymetallic nodules from the Central Indian Ocean Basin

    Digital Repository Service at National Institute of Oceanography (India)

    Valsangkar, A.B.; Karisiddaiah, S.M.; Parthiban, G.

    Chemical composition of 613 polymetallic nodules from 150 stations in the Central Indian Ocean Basin (CIOB) are determined and variations in Mn, Fe, Cu, Ni, Co, Zn and moisture content are studied with respect to their size and surface texture...

  15. Size Resolved Mass Concentration and Chemical Composition of Atmospheric Aerosols over the Eastern Mediterranean Area

    Czech Academy of Sciences Publication Activity Database

    Smolík, Jiří; Ždímal, Vladimír; Lazaridis, M.; Schwarz, Jaroslav; Havránek, Vladimír; Eleftheriadis, K.; Colbeck, I.; Mihalopoulos, N.; Nyeki, S.; Housiadas, C.

    Kjeller: Norwegian Institute for Air Research, 2002 - (Kahnert, M.), s. 26-51. (Report.. 4) Grant ostatní: EVK2(XE) CT/1999/000052 Keywords : atmospheric aerosols * Mediterranean area * chemical composition Subject RIV: CF - Physical ; Theoretical Chemistry

  16. Chemical composition and antibacterial activity of essential oils against human pathogenic bacteria

    NARCIS (Netherlands)

    Sokovic, M.; Marin, P.D.; Brkic, D.; Griensven, van L.J.L.D.

    2008-01-01

    The chemical composition and antibacterial activity of essential oils from 10 aromatic plants Matricaria chamommilla, Mentha piperita, M. spicata, Lavandula angustifolia, Ocimum basilicum, Thymus vulgaris, Origanum vulgare, Salvia officinalis, Citrus limon and C. aurantium have been determined. Anti

  17. Differential effects of conifer and broadleaf litter inputs on soil organic carbon chemical composition through altered soil microbial community composition.

    Science.gov (United States)

    Wang, Hui; Liu, Shi-Rong; Wang, Jing-Xin; Shi, Zuo-Min; Xu, Jia; Hong, Pi-Zheng; Ming, An-Gang; Yu, Hao-Long; Chen, Lin; Lu, Li-Hua; Cai, Dao-Xiong

    2016-01-01

    A strategic selection of tree species will shift the type and quality of litter input, and subsequently magnitude and composition of the soil organic carbon (SOC) through soil microbial community. We conducted a manipulative experiment in randomized block design with leaf litter inputs of four native subtropical tree species in a Pinus massoniana plantation in southern China and found that the chemical composition of SOC did not differ significantly among treatments until after 28 months of the experiment. Contrasting leaf litter inputs had significant impacts on the amounts of total microbial, Gram-positive bacterial, and actinomycic PLFAs, but not on the amounts of total bacterial, Gram-negative bacterial, and fungal PLFAs. There were significant differences in alkyl/O-alkyl C in soils among the leaf litter input treatments, but no apparent differences in the proportions of chemical compositions (alkyl, O-alkyl, aromatic, and carbonyl C) in SOC. Soil alkyl/O-alkyl C was significantly related to the amounts of total microbial, and Gram-positive bacterial PLFAs, but not to the chemical compositions of leaf litter. Our findings suggest that changes in forest leaf litter inputs could result in changes in chemical stability of SOC through the altered microbial community composition. PMID:27256545

  18. Chemical composition and antioxidant activities of Jeddah corniche algae, Saudi Arabia

    OpenAIRE

    Al-Amoudi, Omar A.; Mutawie, Hawazin H.; Patel, Asmita V.; Blunden, Gerald

    2009-01-01

    The increased use of natural product in the pharmaceutical industry has led to an increase in demand for screening for bioactive compounds in marine algae. An important economic algae, through chemical composition analysis and their antioxidant activities were investigated in this study. Chemical composition analysis of three algal samples from the Chlorophyta Ulva lactuca (U), Phaeophyta Sargassum crassifolia (S) and Rhodophyta Digenea simplex (D) was tested. Main components were sugars (57....

  19. The method of modelling of relationships between hardenability and chemical composition of the constructional alloy steels

    International Nuclear Information System (INIS)

    Basing on the experimental results of the hardenability investigations, which employed Jominy method, the model of the neural networks was developed and fully verified experimentally. The model makes it possible to obtain Jominy hardenability curves basing on the steel chemical composition. The model of neural networks, making it possible to design the steel chemical composition, basing on the known Jominy hardenability curve shape, was developed also and fully verified numerically. The practical usability of the models developed is presented. (author)

  20. Chemical composition of leaf extracts of Stevia rebaudiana Bertoni grown experimentally in Vojvodina

    OpenAIRE

    IVANA S. MARKOVIC; ZOLTAN A. DJARMATI; BILJANA F. ABRAMOVIC

    2008-01-01

    The chemical composition of leaf extracts of Stevia rebaudiana Bertoni, grown for the first time on an experimental field near Zrenjanin, was examined by GC–MS. The tested plant material was harvested in September of 2002. To analyze the chemical composition of the lipophilic components of the plant leaves, essential oils and ethyl acetate extract were isolated. Qualitative analysis of the essential oil obtained by hydrodistillation showed that among the identified 88 compounds, the majority ...

  1. Determination of the chemical composition of tea by chromatographic methods: a review

    OpenAIRE

    Alexandr Ya. Yashin; Nemzer, Boris V; Emilie Combet; Yakov I. Yashin

    2015-01-01

    Despite the fact that mankind has been drinking tea for more than 5000 years, its chemical composition has been studied only in recent decades. These studies are primarily carried out using chromatographic methods. This review summarizes the latest information regarding the chemical composition of different tea grades by different chromatographic methods, which has not previously been reviewed in the same scope. Over the last 40 years, the qualitative and quantitative analyses of high volatil...

  2. SCREENING OF CHEMICAL COMPOSITIONS OF CRUDE WATER EXTRACT OF DIFFERENT CASSAVA VARIETIES

    OpenAIRE

    Olajumoke Oke FAYINMINNU; Olubunmi Omowunmi FADINA; Alex Adeoluwa ADEDAPO

    2013-01-01

    Chemical composition of three sources of crude cassava water extract (CCWE) was evaluated in different varieties of cassava (MS6 Manihot Selection (local variety), TMS 30555 Tropical Manihot Selection (Improved variety) and Bulk (crude cassava water from cassava processing site). Crude cassava water extract from the pulp of cassava fresh roots was prepared and the chemical composition was determined in the analytical laboratory. The result of the analysis showed that, hydrocyanic acid (HCN) ...

  3. Precipitation of niobium carbonitrides in ferrite: chemical composition measurements and thermodynamic modelling

    OpenAIRE

    Perez, Michel; Courtois, E.; Acevedo, D.; T. Epicier; Maugis, Philippe

    2007-01-01

    High-resolution transmission electron microscopy and electron-energy loss spectroscopy have been used to characterize the structure and chemical composition of niobium carbonitrides in the ferrite of a Fe–Nb–C–N model alloy at different precipitation stages. Experiments seem to indicate the coexistence of two types of precipitates: pure niobium nitrides and mixed substoichiometric niobium carbonitrides. In order to understand the chemical composition of these precipitates, a thermodynamic for...

  4. Influence of the chemical composition on gamma ray attenuation by fatty acids.

    Science.gov (United States)

    Bhandal, G S; Singh, K

    1992-04-01

    The dependence of gamma ray attenuation on the chemical composition of fatty acids is investigated in the energy range from 10(-3) to 10(5) MeV. The mass attenuation coefficients (muF) and effective atomic numbers (Zeff) have been calculated for 27 different fatty acids. They show appreciable variation with the chemical composition of fatty acids in the region of gamma ray energies from 10(-3) to 10(5) MeV. PMID:1314792

  5. Chemical Composition and Antioxidant Activity of Essential Oils of Twelve Spice Plants

    OpenAIRE

    Politeo, Olivera; Jukić, Mila; Miloš, Mladen

    2006-01-01

    Chemical compositions and related total antioxidant capacities of twelve spice essential oils were analyzed. To enable a comparison of their relative antioxidant potentials, essential oils were extracted by hydrodistillation from selected spice plants and their chemical compositions were determined by the GC-MS system on two fused-silica capillary columns of different polarity. Antioxidant effectiveness was examined by four different methods: the 2,2'-diphenyl- 1-picrylhydrazyl (DPPH) radical...

  6. Microflora and chemical composition of dental plaque from subjects with hereditary fructose intolerance.

    OpenAIRE

    Hoover, C I; Newbrun, E; Mettraux, G; Graf, H

    1980-01-01

    We compared the microbiological and chemical composition of dental plaque from subjects with hereditary fructose intolerance who restrict their dietary sugar intake with that of control subjects who do not. The two groups showed no significant differences in chemical composition of plaque: the mean protein, carbohydrate, calcium, magnesium, and phosphate contents were similar. Dental plaque from both groups contained similar numbers of total colony-forming units per microgram of plaque protei...

  7. Chemical compositions of the moon, earth, and eucrite parent body

    Science.gov (United States)

    Anders, E.

    1977-01-01

    Model compositions of the moon and earth were calculated on the assumption that these planets had experienced chondrite-like nebular fractionation processes. The model correctly predicts the abundance ratios of certain volatile/refractory element pairs (e.g., Cd/Ba, Ga/La, Sn/Th, and Pb/U), the density of the moon, and the major rock types. The model is also used to reconstruct the composition of the parent eucrite body, which resembles the moon except for a lower content of refractory elements.

  8. Mechanical and Chemical Properties of Bamboo/Glass Fibers Reinforced Polyester Composites

    Directory of Open Access Journals (Sweden)

    K.Sudha Madhuri,

    2016-01-01

    Full Text Available The chemical resistance of Bamboo/Glass reinforced Polyester hybrid composites to acetic acid, Nitric acid, Hydrochloric acid, Sodium hydroxide, Sodium carbonate, Benzene, Toluene, Carbon tetrachloride and Water was studied. The tensile and impact properties of these composites were also studied. The effect of alkali treatment of bamboo fibers on these properties was studied. It was observed that the tensile and impact properties of the hybrid composites increase with glass fiber content. The author investigated the interfacial bonding between Glsss/Bamboo fiber composites by SEM. These properties found to be higher when alkali treated bamboo fibers were used in hybrid composites. The hybrid fiber composites showed better resistance to the chemicals mentioned above. The elimination of amorphous hemi-cellulose with alkali treatment leading to higher crystallinity of the bamboo fibers with alkali treatment may be responsible for these observations.

  9. Size Resolved Chemical Composition of Atmospheric Aerosols Collected in Winter over the Eastern Mediterranean Area

    Czech Academy of Sciences Publication Activity Database

    Smolík, Jiří; Ždímal, Vladimír; Eleftheriadis, K.; Havránek, Vladimír; Mihalopoulos, N.; Schwarz, Jaroslav; Colbeck, I.; Lazaridis, M.

    Vol. 1. Taipei, 2002 - (Wang, C.), s. 301-302 ISBN 986-80544-1-9. [International Aerosol Conference /6./. Taipei, (TW), 09.09.2002-13.09.2002] Grant ostatní: EVK2(XE) CT/1999/00052 Keywords : atmospheric aerosols * elemental composition * chemical composition Subject RIV: CF - Physical ; Theoretical Chemistry

  10. Chemical composition and the nature of the surface of type A3B5 compounds

    International Nuclear Information System (INIS)

    The results of studies in admixture and phase compositions, nature of the surface active centers of semiconductor compounds InB5+ (B = Sb, As, P) are analyzed. Changes in chemical composition, acid-basic properties, activity of the InB5+ compounds real surface during thermal processing and mechanochemical activation are traced on the basis of the performed studies

  11. The Composition of 433 Eros: A Mineralogical-Chemical Synthesis

    Science.gov (United States)

    McCoy, T. J.; Gaffey, M.; Bell, J. F., III; Boynton, W. V.; Burbine, T. H.; Chapman, C. R.; Cheng, A.; Clark, P. E.; Evans, L. G.; Gorenstein, P.

    2001-01-01

    We report on an effort with the Near-Infrared Spectrometer/Multi-Spectral Imager (NIS/MSI) and X-ray/Gamma-ray Spectrometer (XGRS) teams to synthesize our data sets to constrain the relationship between Eros and meteorites; the mineralogy, abundances and compositions of Eros; and the processes that formed Eros. Additional information is contained in the original extended abstract.

  12. The Chemical Composition of an Extrasolar Minor Planet

    OpenAIRE

    Zuckerman, B.; D. Koester; Melis, C; Hansen, B.; Jura, M.

    2007-01-01

    We report the relative abundances of 17 elements in the atmosphere of the white dwarf star GD 362, material that, very probably, was contained previously in a large asteroid or asteroids with composition similar to the Earth/Moon system. The asteroid may have once been part of a larger parent body not unlike one of the terrestrial planets of our solar system.

  13. Mechanical and Chemical Properties of Bamboo/Glass Fibers Reinforced Polyester Composites

    OpenAIRE

    K.Sudha Madhuri,; H.Raghavendra Rao

    2016-01-01

    The chemical resistance of Bamboo/Glass reinforced Polyester hybrid composites to acetic acid, Nitric acid, Hydrochloric acid, Sodium hydroxide, Sodium carbonate, Benzene, Toluene, Carbon tetrachloride and Water was studied. The tensile and impact properties of these composites were also studied. The effect of alkali treatment of bamboo fibers on these properties was studied. It was observed that the tensile and impact properties of the hybrid composites increase with glass fiber ...

  14. Areca Fiber Reinforced Epoxy Composites: Effect of Chemical Treatments on Impact Strength

    OpenAIRE

    Dhanalakshmi, S.; Ramadevi, P.; Basavaraju, B.

    2015-01-01

    In this research work, impact strength of untreated, alkali treated, potassium permanganate treated, benzoyl chloride treated and acrylic acid treated areca fiber reinforced epoxy composites were studied under 40%, 50%, 60% and 70% fiber loadings. Impact strength increased with increase in fiber loading up to 60% and then showed a decline for all untreated and chemically treated areca fiber reinforced epoxy composites. The acrylic acid treated areca fiber reinforced epoxy composites with 60% ...

  15. Chemical composition and in vitro dry matter digestibility of lichens

    Directory of Open Access Journals (Sweden)

    Torstein H. Garmo

    1986-06-01

    Full Text Available The chemical composition and in vitro dry matter digestibility of 45 samples of different species of lichen are reported. Mean content (g/100 g dry matter of the main nutrients was: crude protein 4.2, crude fat 3.2, crude fibre 16.6, ash 1.9, Ca 0.15, P 0.09, Mg 0.05, K 0.13, Na 0.035, S 0.07. The content of microminerals (mg/kg dry matter was: Cu 2.5, Mo 0.11, Zn 27.2, Se 0.12, Fe 898, Mn 154. The mean in vitro dry matter digestibility was 35%. However, the in vitro method do underestimate the dry matter digestibility of lichens. Stereocaulon spp. showed higher levels of crude protein, P, S, Cu and Mo than Cetraria spp. and Cladonia spp. Cetraria nivalis showed higher digestibility and contained more NFE, ash, Ca, Mg, but less crude fibre than Cladonia stellaris. Lichens contained less amounts of most nutrients compared with grasses (Fig. 1, exept for crude fat, NFE, Se and Fe.Kjemisk innhald og in vitro fordøyelsesgrad av lav.Abstract in Norwegian / Samandrag: Kjemisk innhald og in vitro fordøyelsesgrad av tørrstoffet er bestemt i 45 prøver av beitelav frå to stader i Sør-Noreg. Middel innhald (g/100g tørrstoff av følgjande næringsstoff var: protein 4.2, feitt 3.2, trevlar 16.6, oske 1.9, kalsium 0.15, fosfor 0.09, magnesium 0.05, kalium 0.13, natrium 0.035, svovel 0.07. Innhaldet (mg/kg tørrstoff av mikronæringsstoffa var: kopar 2.5, molybden 0.11, sink 27.2, selen 0.12, jern 898 og mangan 154. Den midlare fordøyelsesgraden av tørrstoffet i lav-prøvene var 35%, men in vitro fordøyelsesanalyser undervurderer fordøyelsesgraden av lav. Det var ein stor variasjon mellom dei ulike lavartane for dei fleste næringsstoffa og fordøyelsesgraden. Stereocaulon spp. inneheldt meir protein, fosfor, svovel, kopar og molybden enn Cetraria spp. og Cladonia spp. Gulskinn hadde høgare fordøyelsesgrad, og innehaldet av NFE, oske, kalsium og magnesium var høgre enn i kvitkrull, medan trevleinnhaldet var størst i kvitkrull. Lav inneheldt

  16. Fabrication of fiber-reinforced composites by chemical vapor infiltration

    Energy Technology Data Exchange (ETDEWEB)

    Besmann, T.M.; Stinton, D.P. [Oak Ridge National Lab., TN (United States); Matlin, W.M.; Liaw, P.K. [Univ. of Tennessee, Knoxville, TN (United States)

    1996-08-01

    Processing equipment for the infiltration of fiber-reinforced composite tubes is being designed that incorporates improvements over the equipment used to infiltrate disks. A computer-controlled machine-man interface is being developed to allow for total control of all processing variables. Additionally, several improvements are being made to the furnace that will reduce the complexity and cost of the process. These improvements include the incorporation of free standing preforms, cast mandrels, and simpler graphite heating elements.

  17. CHEMICAL COMPOSITION AND ANTIMICROBIAL PROPERTIES OF DIFFERENT BASIL OILS

    OpenAIRE

    H.C. Srivastava, Pankaj Shukla, Ajay Singh Maurya and Sonia Tripathi*

    2013-01-01

    ABSTRACT: The aerial parts essential oils of Ocimum basilicum (Lamiaceae) from Togo were steam-distilled and investigated for their percentage composition (GC and GC/MS) and in vitro antimicrobial activities. Five oil chemotypes were identified and classified as follows in line with their principal components: estragole type; linalool/estragole type; methyleugenol type; methyleugenol/t-anethole type; tanethole type. The in vitro microbiological experiments revealed that only the methyleugenol...

  18. Fabrication of fiber-reinforced composites by chemical vapor infiltration

    Energy Technology Data Exchange (ETDEWEB)

    Besmann, T.M.; Matlin, W.M.; Stinton, D.P.; Liaw, P.K.

    1996-06-01

    Processing equipment for the infiltration of fiber-reinforced composite tubes is being designed that incorporates improvements over the equipment used to infiltrate disks. A computer-controlled machine-man interface is being developed to allow for total control of all processing variables. Additionally, several improvements are being made to the furnace that will reduce the complexity and cost of the process. These improvements include the incorporation of free standing preforms, cast mandrels, and simpler graphite heating elements.

  19. Simaroubaceae family: botany, chemical composition and biological activities

    Directory of Open Access Journals (Sweden)

    Iasmine A.B.S. Alves

    2014-08-01

    Full Text Available The Simaroubaceae family includes 32 genera and more than 170 species of trees and brushes of pantropical distribution. The main distribution hot spots are located at tropical areas of America, extending to Africa, Madagascar and regions of Australia bathed by the Pacific. This family is characterized by the presence of quassinoids, secondary metabolites responsible of a wide spectrum of biological activities such as antitumor, antimalarial, antiviral, insecticide, feeding deterrent, amebicide, antiparasitic and herbicidal. Although the chemical and pharmacological potential of Simaroubaceae family as well as its participation in official compendia; such as British, German, French and Brazilian pharmacopoeias, and patent registration, many of its species have not been studied yet. In order to direct further investigation to approach detailed botanical, chemical and pharmacological aspects of the Simaroubaceae, the present work reviews the information regarding the main genera of the family up to 2013.

  20. Chemical composition and machinability of selected species from Mozambique

    OpenAIRE

    Lhate, Inacio Arnaldo

    2011-01-01

    The objectives of the current work were to carry out a survey on timber sector in Mozambique and to determine chemical, calorific and machinability features of selected species. Mozambican timber sector was described as dominated by selective harvesting practices on a few hardwood species out of 118 species growing in the forest with potential for industrial timber. Selective logging is believed to be due to the demand in both domestic and international markets of traditionally used, and lack...

  1. Chemical composition on cacao leaves infected by viruses

    International Nuclear Information System (INIS)

    Chemical analysis on cacao leaves that have chlorosis spots caused by cocoa swollen shoot viruses were carried out. It can be shown that leaves with chlorosis spots contain less chlorophyl and lipides than those without, but both do not show any significant difference in the concentration of water, glucose, saccharides, amino acid and proteins. It can be concluded that transport systems in the infected leaves are good so that the water and saccharides distribution in them are not disturbed. (author tr.)

  2. Chemical compositions of two different Thymus species essential oils

    OpenAIRE

    Samira Jaberi; Mahmoodreza Moein; Azizolah Jafari; Forough Karami

    2015-01-01

    Thymus is one of the most important members of Lamiaceae family. Aerial parts of the plant have been widely used in medicine. It has been reported that most of these effects are related to phenolic compounds especially thymol and carvacrol in Thymus essential oil. In this study, aerial parts of Thymus daenensis and Thymus lancifolius were collected from Kohgiluyeh and Boyer-Ahmad, Iran. Essential oils of aerial parts of these plants were gained by the hydrodistillation method and the chemical...

  3. Chemical composition of Nigella sativa Linn: Part 2 Recent advances.

    Science.gov (United States)

    Akram Khan, M; Afzal, M

    2016-06-01

    The black cumin or Nigella sativa L. seeds have many acclaimed medicinal properties such as bronchodilatory, hypotensive, antibacterial, antifungal, analgesic, anti-inflammatory and immunopotentiating. This review article is an update on the previous article published on Nigella sativa L. in this journal in 1999. It covers the medicinal properties and chemical syntheses of the alkaloids isolated from the seeds of the herb. PMID:27068721

  4. Wine: a review of the chemical composition and health benefits

    OpenAIRE

    Claudriana Locatelli; Vanderléia de Moraes

    2010-01-01

    The presence of antioxidants in red wine has attracted increasing scientific interest in the evidence of its benefits to health. The study aimed to analyze the benefits of the chemical components of wine on human health. The study was qualitative nature by assessment scientific papers that analyze the relationship of the health benefits of wine consumption when used controlled way. Resveratrol is the main component of wine studied, being this way, the majority of publications associated with ...

  5. Production and chemical composition of Istria and Pag whey cheese

    Directory of Open Access Journals (Sweden)

    Neven Antunac

    2011-12-01

    Full Text Available Istria and Pag curd are specific products that are mostly consumed fresh made in coastal areas and on islands. Curd is a sort of soft cheese. Due to its structure, it is very healthy. It has a high nutritional value which is the result of a great amount of proteins that are easy to digest and have a high level of utilization. The aim of this study was to describe the technological process of production, to determine the chemical structure and to suggest the value of standardization on the basis of sensory evaluation. The total of 28 curd samples were physically and chemically analyzed according to standard and accredited scientific methods. Statistical data analysis was carried out by using the procedures of Microsoft Office Excel (2007. According to water content in cheese, Istria and Pag curd belongs to a group of soft cheeses. On average the water content in Istrian curd was 56.62 %, and in Pag curd was 63.03 %. Istrian curd showed higher values of the fat content (28.9 % and the fat in a dry matter (64.47 % than Pag curd (23.25 % and 59.65 %. The sensory quality of Istrian curd was not as homogenous as of Pag curd. Based on the research results, it can be concluded that the physical and chemical structure of Istria and Pag curd was uneven, which is understandable if the production terms and conditions and the way of draining the curd are taken into account. The description of technological process of production and the understanding of physical and chemical structure of the curd, represent the significant contribution to the research and knowledge of domestic dairy products, which certainly should not be neglected in our dairy industry. In any case, these products deserve the experts full attention.

  6. Chemical composition on cacao leaves infected by viruses

    Energy Technology Data Exchange (ETDEWEB)

    Mustafa, M.; Delilah, M.; Syafrul, L.; Suryadi

    1980-09-01

    Chemical analysis on cacao leaves that have chlorosis spots caused by cacao swollen shoot viruses were carried out. It can be shown that leaves with chlorosis spots contain less chlorophyl and lipides than those without, but both do not show any significant difference in the concentration of water, glucose, saccharides, amino acid and proteins. It can be concluded that transport systems in the infected leaves are good so that the water and saccharides distribution in them are not disturbed.

  7. Direct Monte Carlo simulation of the chemical equilibrium composition of detonation products

    Energy Technology Data Exchange (ETDEWEB)

    Shaw, M.S.

    1993-06-01

    A new Monte Carlo simulation method has been developed by the author which gives the equilibrium chemical composition of a molecular fluid directly. The usual NPT ensemble (isothermal-isobaric) is implemented with N being the number of atoms instead of molecules. Changes in chemical composition are treated as correlated spatial moves of atoms. Given the interaction potentials between molecular products, ``exact`` EOS points including the equilibrium chemical composition can be determined from the simulations. This method is applied to detonation products at conditions in the region near the Chapman- Jouget state. For the example of NO, it is shown that the CJ detonation velocity can be determined to a few meters per second. A rather small change in cross potentials is shown to shift the chemical equilibrium and the CJ conditions significantly.

  8. Indirect Determination of Chemical Composition and Fuel Characteristics of Solid Waste

    DEFF Research Database (Denmark)

    Riber, Christian; Christensen, Thomas Højlund

    Determination of chemical composition of solid waste can be performed directly or indirectly by analysis of combustion products. The indirect methodology instrumented by a full scale incinerator is the only method that can conclude on elements in trace concentrations. These elements are of great...... interest in evaluating waste management options by for example LCA modeling. A methodology description of indirect determination of chemical composition and fuel properties of waste is provided and validated by examples. Indirect analysis of different waste types shows that the chemical composition is...... significantly dependent on waste type. And the analysis concludes that the transfer of substances in the incinerator is a function of waste chemical content, incinerator technology and waste physical properties. The importance of correct representation of rare items in the waste with high concentrations of...

  9. Chemical composition of primary cosmic rays with IceCube

    Science.gov (United States)

    Xu, Chen

    Ground detector arrays have been used to measure high energy cosmic rays for decades to overcome their very low rate. IceCube is a special case with its 3D deployment and unique location---the South Pole. Although all 86 strings and 81 stations of IceCube were completed in 2011, IceCube began to take data in 2006, after the completion of the first 9 strings. In this thesis, experimental data taken in 2009 with 59 strings are used for composition analysis albeit some techniques are illustrated with the 40-string data. Simulation is essential in the composition work. Simulated data must be compared against the experimental data to find the right mix of cosmic ray components. However, because of limited computing resources and complexities of cosmic rays, the simulation in IceCube is well behind the experiment. The lower and upper bounds of primary energy in simulation for events that go through IceTop and the deep arrays of IceCube are 1014 eV and 1017 eV. However, since IceCube has a threshold energy about several hundred TeV, and an upper limit of 10 18 eV, the full energy range cannot be explored in this thesis. The approach taken to the composition problem in this thesis is a 2D Bayesian unfolding. It takes account of the measured IceTop and InIce energy spectrum and outputs the expected primary energy spectrum of different mass components. Studies of the uncertainties in the results are not complete because of limited simulation and understanding of the new detector and South Pole environment.

  10. Simulation of aerosol chemical compositions in the Western Mediterranean Sea

    Science.gov (United States)

    Chrit, Mounir; Kata Sartelet, Karine; Sciare, Jean; Marchand, Nicolas; Pey, Jorge; Sellegri, Karine

    2016-04-01

    This work aims at evaluating the chemical transport model (CTM) Polair3d of the air-quality modelling platform Polyphemus during the ChArMex summer campaigns of 2013, using ground-based measurements performed at ERSA (Cape Corsica, France), and at determining the processes controlling organic aerosol concentrations at ERSA. Simulations are compared to measurements for concentrations of both organic and inorganic species, as well as the ratio of biogenic versus anthropogenic particles, and organic aerosol properties (oxidation state). For inorganics, the concentrations of sulphate, sodium, chloride, ammonium and nitrate are compared to measurements. Non-sea-salt sulphate and ammonium concentrations are well reproduced by the model. However, because of the geographic location of the measurement station at Cape Corsica which undergoes strong wind velocities and sea effects, sea-salt sulphate, sodium, chloride and nitrate concentrations are strongly influenced by the parameterizations used for sea-salt emissions. Different parameterizations are compared and a parameterization is chosen after comparison to sodium measurements. For organics, the concentrations are well modelled when compared to experimental values. Anthropogenic particles are influenced by emission of semi-volatile organic compounds (SVOC). Measurements allow us to refine the estimation of those emissions, which are currently missing in emission inventories. Although concentrations of biogenic particles are well simulated, the organic chemical compounds are not enough oxidised in the model. The observed oxidation state of organics shows that the oligomerisation of pinonaldehyde was over-estimated in Polyphemus. To improve the oxidation property of organics, the formation of extremely low volatile organic compounds from autoxidation of monoterpenes is added to Polyphemus, using recently published data from chamber experiments. These chemical compounds are highly oxygenated and are formed rapidly, as first

  11. Fabrication of fiber-reinforced composites by chemical vapor infiltration

    Energy Technology Data Exchange (ETDEWEB)

    Matlin, W.M. [Univ. of Tennessee, Knoxville, TN (United States); Stinton, D.P.; Besmann, T.M. [Oak Ridge National Lab., TN (United States)

    1995-08-01

    A two-step forced chemical vapor infiltration process was developed that reduced infiltration times for 4.45 cm dia. by 1.27 cm thick Nicalon{sup +} fiber preforms by two thirds while maintaining final densities near 90 %. In the first stage of the process, micro-voids within fiber bundles in the cloth were uniformly infiltrated throughout the preform. In the second stage, the deposition rate was increased to more rapidly fill the macro-voids between bundles within the cloth and between layers of cloth. By varying the thermal gradient across the preform uniform infiltration rates were maintained and high final densities achieved.

  12. Effect of Rain Leaching on Chemical Composition of Alfalfa Hay

    OpenAIRE

    Garcia de Hernandez, Mercedes M.

    1981-01-01

    Yield and chemical changes of second-cutting alfalfa hay treated with artificial rain were determined in a 2 x 3 x 2 factorial experiment. Factors were 2 stages of maturity (1 late vegetative; 2 early bloom), 3 levels of artificial rain applied (1 =no rain; 2 =low or approximately 5 mm; 3 =high or approximately 20 mm), and 2 times of applying artificial rain (1 = when drying forage was 40-60% dry matter; 2 =when drying forage was 60-75% dry matter). Thirty samples of alfalfa were collected at...

  13. Fabrication of fiber-reinforced composites by chemical vapor infiltration

    Energy Technology Data Exchange (ETDEWEB)

    Besmann, T.M.; McLaughlin, J.C. [Oak Ridge National Lab., TN (United States). Metals and Ceramics Div.; Probst, K.J.; Anderson, T.J. [Univ. of Florida, Gainesville, FL (United States). Dept. of Chemical Engineering; Starr, T.L. [Georgia Inst. of Tech., Atlanta, GA (United States). Dept. of Materials Science and Engineering

    1997-12-01

    Silicon carbide-based heat exchanger tubes are of interest to energy production and conversion systems due to their excellent high temperature properties. Fiber-reinforced SiC is of particular importance for these applications since it is substantially tougher than monolithic SiC, and therefore more damage and thermal shock tolerant. This paper reviews a program to develop a scaled-up system for the chemical vapor infiltration of tubular shapes of fiber-reinforced SiC. The efforts include producing a unique furnace design, extensive process and system modeling, and experimental efforts to demonstrate tube fabrication.

  14. Tuning Chemical Potential in the Dirac Cone by Compositional Engineering

    OpenAIRE

    Gopal, R. K.; Singh, Sourabh; Sarkar, Jit; Mitra, Chiranjib

    2016-01-01

    We report the successful formation of bulk insulating ternary topological insulators candidate Bi2Se2Te (BST) by pulsed laser deposition technique. The films were deposited with sequential ablation of separate Bi2Se3 (BS) and Bi2Te3 (BT) targets. From the X-ray diffraction analysis and temperature dependent resistivity we were able to conclude that the as grown thin films have ordered chalcogen layers and the chemical potential in these thin films lie in the bulk gap. To realize entirely topo...

  15. Quantification of aerosol chemical composition using continuous single particle measurements

    OpenAIRE

    C.-H. Jeong; M. L. McGuire; K. J. Godri; Slowik, J. G.; P. J. G. Rehbein; G. J. Evans

    2011-01-01

    Mass concentrations of sulphate, nitrate, ammonium, organic carbon (OC), elemental carbon (EC) were determined from real time single particle data in the size range 0.1–3.0 μm measured by an Aerosol Time-of-Flight Mass Spectrometer (ATOFMS) at urban and rural sites in Canada. To quantify chemical species within individual particles measured by an ATOFMS, ion peak intensity of m/z −97 for sulphate, −62 for nitrate, +18 for ammonium, +43 for OC, and +36 for EC were scaled usi...

  16. Quantification of aerosol chemical composition using continuous single particle measurements

    OpenAIRE

    Jeong, C.-H.; M. L. McGuire; K. J. Godri; Slowik, J. G.; P. J. G. Rehbein; G. J. Evans

    2011-01-01

    Mass concentrations of sulphate, nitrate, ammonium, organic carbon (OC), elemental carbon (EC) were determined from real time single particle data in the size range 0.1–3.0 μm measured by an Aerosol Time-of-Flight Mass Spectrometer (ATOFMS) at urban and rural sites in Canada. To quantify chemical species within individual particles measured by an ATOFMS, ion peak intensity of m/z −97 for sulphate, −62 for nitrate, +18 for ammonium, +43 for OC, and +36 for EC were scaled usin...

  17. Chemical Composition and Antioxidant Capacity of Brazilian Passiflora Seed Oils.

    Science.gov (United States)

    de Santana, Fernanda Carvalho; Shinagawa, Fernanda Branco; Araujo, Elias da Silva; Costa, Ana Maria; Mancini-Filho, Jorge

    2015-12-01

    The seed oils of different varieties of 4 Passiflora species cultivated in Brazil were analyzed and compared regarding their physicochemical parameters, fatty acid composition and the presence of minor components, such as phytosterols, tocopherols, total carotenoids, and phenolic compounds. The antioxidant capacities of the oil extracts were determined using the 2,2'azinobis [3-ethylbenzothiazoline-6-sulfonic acid] and oxygen radical absorbance capacity methods. The results revealed that all studied Passiflora seed oils possessed similar physicochemical characteristics, except for color, and predominantly contained polyunsaturated fatty acids with a high percentage of linolenic acid (68.75% to 71.54%). Other than the total phytosterol content, the extracted oil from Passiflora setacea BRS Pérola do Cerrado seeds had higher quantities (% times higher than the average of all samples), of carotenoids (44%), phenolic compounds (282%) and vitamin E (215%, 56%, 398%, and 100% for the α-tocopherol, β-tocopherol, γ-tocopherol, and δ-tocopherol isomers, respectively). The methanolic extracts from Passiflora setacea BRS Pérola do Cerrado seed oil also showed higher antioxidant activity, which was positively correlated with the total phenolic, δ-tocopherol, and vitamin E contents. For the first time, these results indicate that Passiflora species have strong potential regarding the use of their seeds for oil extraction. Due to their interesting composition, the seed oils may be used as a raw material in manufacturing industries in addition to other widely used vegetable oils. PMID:26512548

  18. Nanoscale chemical interaction enhances the physical properties of bioglass composites.

    Science.gov (United States)

    Ravarian, Roya; Zhong, Xia; Barbeck, Mike; Ghanaati, Shahram; Kirkpatrick, Charles James; Murphy, Ciara M; Schindeler, Aaron; Chrzanowski, Wojciech; Dehghani, Fariba

    2013-10-22

    Bioglasses are favorable biomaterials for bone tissue engineering; however, their applications are limited due to their brittleness. In addition, the early failure in the interface is a common problem of composites of bioglass and a polymer with high mechanical strength. This effect is due to the phase separation, nonhomogeneous mixture, nonuniform mechanical strength, and different degradation properties of two compounds. To address these issues, in this study a nanoscale interaction between poly(methyl methacrylate) (PMMA) and bioactive glass was formed via silane coupling agent (3-trimethoxysilyl)propyl methacrylate (MPMA). A monolith was produced at optimum composition from this hybrid by the sol-gel method at 50 °C with a rapid gelation time (hybrid. The in vivo studies in mice demonstrated that the integrity of the hybrids was maintained in subcutaneous implantation. They induced mainly a mononuclear phagocytic tissue reaction with a low level of inflammation, while bioglass provoked a tissue reaction with TRAP-positive multinucleated giant cells. These results demonstrated that the presence of a nanoscale interaction between bioglass and PMMA affects the properties of bioglass and broadens its potential applications for bone replacement. PMID:24001050

  19. On the Formation and Chemical Composition of Super Earths

    CERN Document Server

    Alessi, Matthew; Cridland, Alex J

    2016-01-01

    Super Earths are the largest population of exoplanets and are seen to exhibit a rich diversity of compositions as inferred through their mean densities. Here we present a model that combines equilibrium chemistry in evolving disks with core accretion that tracks materials accreted onto planets during their formation. In doing so, we aim to explain why super Earths form so frequently and how they acquire such a diverse range of compositions. A key feature of our model is disk inhomogeneities, or planet traps, that act as barriers to rapid type-I migration. The traps we include are the dead zone, which can be caused by either cosmic ray or X-ray ionization, the ice line, and the heat transition. We find that in disks with sufficiently long lifetimes ($\\gtrsim$ 4 Myr), all traps produce Jovian planets. In these disks, planet formation in the heat transition and X-ray dead zone produces hot Jupiters while the ice line and cosmic ray dead zones produce Jupiters at roughly 1 AU. Super Earth formation takes place wi...

  20. An estimate of the chemical composition of Titan's lakes

    CERN Document Server

    Cordier, D; Lunine, J -I; Lavvas, P; Vuitton, V

    2009-01-01

    Hundreds of radar-dark patches interpreted as lakes have been discovered in the north and south polar regions of Titan. We have estimated the composition of these lakes by using the direct abundance measurements from the Gas Chromatograph Mass Spectrometer (GCMS) aboard the Huygens probe and recent photochemical models based on the vertical temperature profile derived by the Huygens Atmospheric Structure Instrument (HASI). Thermodynamic equilibrium is assumed between the atmosphere and the lakes, which are also considered as nonideal solutions. We find that the main constituents of the lakes are ethane (C2H6) (~76-79%), propane (C3H8) (~7-8%), methane (CH4) (~5-10%), hydrogen cyanide (HCN) (~2-3%), butene (C4H8) (~1%), butane (C4H10) (~1%) and acetylene (C2H2) (~1%). The calculated composition of lakes is then substantially different from what has been expected from models elaborated prior to the exploration of Titan by the Cassini-Huygens spacecraft.

  1. 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.

  2. CHEMICAL COMPOSITION AND ANTIMICROBIAL PROPERTIES OF DIFFERENT BASIL OILS

    Directory of Open Access Journals (Sweden)

    H.C. Srivastava, Pankaj Shukla, Ajay Singh Maurya and Sonia Tripathi*

    2013-03-01

    Full Text Available ABSTRACT: The aerial parts essential oils of Ocimum basilicum (Lamiaceae from Togo were steam-distilled and investigated for their percentage composition (GC and GC/MS and in vitro antimicrobial activities. Five oil chemotypes were identified and classified as follows in line with their principal components: estragole type; linalool/estragole type; methyleugenol type; methyleugenol/t-anethole type; tanethole type. The in vitro microbiological experiments revealed that only the methyleugenol and methyleugenol/t-anethole chemotypes were active against tested fungi and bacteria. Their minimum inhibitory concentrations (MIC ranged from 80-150 μL/L and from 200-500 μL/L respectively. Likewise, on tested bacteria the MIC varied from 200-400 μL/L and from 250-500 μL/L respectively. These findings are supportive of the potential of both basil oil chemotypes for use as active ingredients in natural antibiotic drugs.

  3. A New Reference Chemical Composition for TMC-1

    Science.gov (United States)

    Gratier, P.; Majumdar, L.; Ohishi, M.; Roueff, E.; Loison, J. C.; Hickson, K. M.; Wakelam, V.

    2016-08-01

    Recent detections of complex organic molecules in dark clouds have rekindled interest in the astrochemical modeling of these environments. Because of its relative closeness and rich molecular complexity, TMC-1 has been extensively observed to study the chemical processes taking place in dark clouds. We use local thermodynamical equilibrium radiative transfer modeling coupled with a Bayesian statistical method which takes into account outliers to analyze the data from the Nobeyama spectral survey of TMC-1 between 8 and 50 GHz. We compute the abundance relative to molecular hydrogen of 57 molecules, including 19 isotopologues in TMC-1 along with their associated uncertainty. The new results are in general agreement with previous abundance determination from Ohishi & Kaifu and the values reported in the review from Agúndez & Wakelam. However, in some cases, large opacity and low signal to noise effects allow only upper or lower limits to be derived, respectively.

  4. Chemical composition of umbu (Spondias tuberosa Arr. Cam seeds

    Directory of Open Access Journals (Sweden)

    Soraia Vilela Borges

    2007-02-01

    Full Text Available The umbu tree (Spondias tuberosa Arr. Cam is an important fruit tree the economy of the semi-arid northeastern region of Brazil. With the objective of finding use for the seeds, physical and chemical characterizations of the seeds from 2 cultivars in 2 maturation stages were carried out and their fatty acid and mineral profiles determined. The results showed no differences between the seeds analyzed. The yield was about 10% and the dimensions as follows: length from 1.48 to 2.11 cm and width from 0.76 to 1.16 cm. The average lipid content was 55% of which 69% was unsaturated and the average protein content was 24%. The seeds were a good source of the following minerals: P, K, Mg, Fe and Cu. The overall results indicated that the oil or the seeds could be used for food stuffs if no toxic agents were found.

  5. CHEMICAL COMPOSITION AND ANTI-INFLAMMATORY ACTIVITY OF Roldana platanifolia

    Directory of Open Access Journals (Sweden)

    Amira Arciniegas

    2015-11-01

    Full Text Available The chemical study of Roldana platanifolia led to the isolation of β-caryophyllene, five eremophilanolides, chlorogenic acid, and a mixture of β-sitosterol-stigmasterol, β-sitosteryl glucopyranoside, and sucrose. The anti-inflammatory activities of the extracts and isolated products were tested using the 12-O-tetradecanoylphorbol-13-acetate (TPA model of induced acute inflammation. The acetone and methanol extracts showed dose dependent activities (ID50 0.21 and 0.32 mg/ear, respectively, while none of the isolated compounds exhibited relevant edema inhibition. The active extracts were also evaluated with the myeloperoxidase assay technique (MPO to determine their ability to prevent neutrophil infiltration. Results showed that the anti-inflammatory activity was related to the compound’s ability to inhibit pro-inflammatory mediators such as neutrophils.

  6. A study on chemical composition and detection of chemical adulteration in tetra pack milk samples commercially available in Multan.

    Science.gov (United States)

    Awan, Adeela; Naseer, Misbah; Iqbal, Aasfa; Ali, Muhammad; Iqbal, Rehana; Iqbal, Furhan

    2014-01-01

    The aim of this study was to analyze and compare the chemical composition of 8 tetra pack milk samples, Olpers (S1), Haleeb (S2), Good milk (S3), Everyday (S4), Milk Pack (S5), Dairy Queen (S6), Dairy Umang (S7), Nurpur (S8) available in local markets and to detect the presence of various chemical adulterants in tetra pack milk samples in Southern Punjab (Pakistan). Density, pH, solid not fat, total solids, lactometer reading, specific gravity and fat contents were analyzed to determine the chemical composition of milk samples. Our results revealed that all the studied parameters had statistically non significant differences (P>0.05) except total fat in milk samples which was significantly different (P=0.03) among the 8 studied milk samples. Presence of a number of chemical adulterants, formalin, cane sugar, starch, glucose, ammonium sulphate, salt, pulverized soap, detergents, skim milk powder, benzoic acid, salicylic acid, borax, boric acid and alkalinity were also detected in milk samples following standard procedures. Results indicated that formalin, cane sugar, glucose, alkalinity and benzoic acid were present in all samples while salt test was positive only for Olper milk. All other studied adulterants were not detected in 8 milk samples under study. % fat was the only significantly different feature among the studied milk quality parameters with S8 containing lowest while S5 having the maximum % fat. PMID:24374447

  7. The chemical compositions of Galactic disc F and G dwarfs

    Science.gov (United States)

    Reddy, Bacham E.; Tomkin, Jocelyn; Lambert, David L.; Allende Prieto, Carlos

    2003-03-01

    Photospheric abundances are presented for 27 elements from carbon to europium in 181 F and G dwarfs from a differential local thermodynamic equilibrium (LTE) analysis of high-resolution and high signal-to-noise ratio spectra. Stellar effective temperatures (Teff) were adopted from an infrared flux method calibration of Strömgren photometry. Stellar surface gravities (g) were calculated from Hipparcos parallaxes and stellar evolutionary tracks. Adopted Teff and g values are in good agreement with spectroscopic estimates. Stellar ages were determined from evolutionary tracks. Stellar space motions (U, V, W) and a Galactic potential were used to estimate Galactic orbital parameters. These show that the vast majority of the stars belong to the Galactic thin disc. Relative abundances expressed as [X/Fe] generally confirm previously published results. We give results for C, N, O, Na, Mg, Al, Si, S, K, Ca, Sc, Ti, V, Cr, Mn, Co, Ni, Cu, Zn, Sr, Y, Zr, Ba, Ce, Nd and Eu. The α elements - O, Mg, Si, Ca and Ti - show [α/Fe] to increase slightly with decreasing [Fe/H]. Heavy elements with dominant contributions at solar metallicity from the s-process show [s/Fe] to decrease slightly with decreasing [Fe/H]. Scatter in [X/Fe] at a fixed [Fe/H] is entirely attributable to the small measurement errors, after excluding the few thick disc stars and the s-process-enriched CH subgiants. Tight limits are set on `cosmic' scatter. If a weak trend with [Fe/H] is taken into account, the composition of a thin disc star expressed as [X/Fe] is independent of the star's age and birthplace for elements contributed in different proportions by massive stars (Type II supernovae), exploding white dwarfs (Type Ia supernovae) and asymptotic red giant branch stars. By combining our sample with various published studies, comparisons between thin and thick disc stars are made. In this composite sample, thick disc stars are primarily identified by their VLSR in the range -40 to -100 km s-1. These are

  8. Effect of enzyme addition to forage at ensiling on silage chemical composition and NDF degradation characteristics

    DEFF Research Database (Denmark)

    Dehghani, Mohammad Reza; Weisbjerg, Martin Riis; Hvelplund, Torben;

    2012-01-01

    The effect of different exogenous fibrolytic enzymes added to forages at ensiling was examined for effect on chemical composition and in vitro NDF degradability characteristics of the resulting silage. Maize stover and lucerne were used to study effect on chemical composition in experiment 1, and...... two varieties of maize stover, lucerne and grass clover were used to study NDF degradation characteristics in experiment 2. Forages were treated with enzymes (500 mg crude protein of the enzyme products/kg DM) and ensiled for 60 days in vacuum-sealed bags. Samples of forage (before ensiling) and...... silage were analysed for chemical composition and silages were analysed for pH and fermentation products. The in vitro NDF degradation characteristics of four forages treated with selected enzymes were measured by incubation for up to 96 h with rumen fluid. Enzymes with glucanase, β-glucanase and...

  9. Chemical composition of the underutilized legume Cassia hirsuta L.

    Science.gov (United States)

    Vadivel, V; Janardhanan, K

    2000-01-01

    Seven accessions of the underutilized legume, Cassia hirsuta L., seeds collected from seven different agroclimatic regions of Tamil Nadu, India, were analyzed for proximate composition, total proteins, protein fractions, mineral profiles and selected antinutritional factors. Crude protein ranged from 15.52 to 20.74%, crude lipid 3.77-7.04%, crude fiber 4.68-6.92%, ash 3.98-6.42% and carbohydrates 62.45-70.16%. Energy values of the seeds were 1549-1634 kJ/100 g (DM), which are comparable to those of other legumes. Data on seed protein fractions revealed that globulins constituted the bulk of the seed protein as in most legumes. Mineral contents of the seeds showed greater variation. Potassium was the most abundant mineral (1029-1786 mg/100 g), whereas manganese was low (2.1-2.2 mg/100 g). Antinutritional factors such as total free phenolics, tannins, L-DOPA and lectins were analyzed. The results of the study demonstrated that the accessions of C. hirsuta seeds collected from Tamil Nadu, India, could be good sources of some important nutrients for humans. PMID:11086879

  10. Chemical and phytochemical compositions of Voandzeia subterranea seeds.

    Science.gov (United States)

    Marcel, Andzouana; Bienvenu, Mombouli Jean; Attibayeba

    2014-09-01

    The seeds of Voandzeia subterranean (L.) Thouars (Fabaceae), from Congo-Brazzaville were studied for proximate, qualitative and quantitative compositions. Phytochemical screening of various solvent extracts showed the presence of alkaloids, flavonoids, glycosides, saponins, steroids, triterpenoids, phenols, anthocyanins and carotenoids. Tannins and anthraquinones were not found. Quantitative analysis showed a high amount of alkaloids (34.40 ±0.2%), flavonoids (4.93 ± 0.17%), saponins (2.20 ± 0.11%) and anthocyanins (1.00 ± 0.12%) in decreasing order. Phenols (0.60 ± 0.12%) and carotenoids had low yields (0.26 ± 0.07%). Proximate analysis of the seeds showed high moisture, carbohydrate and energy content values (49.14, 20.53% and 956.14 kJ 100 g(-1), respectively). The results showed low ash content (3.84%) and the relatively high fat (7.84%) and protein content (18.65%). The mineral analysis revealed that potassium (3.15%) and phosphorus (1.74%) were the most abundant minerals. Calcium (0.35) and magnesium (0.39%), were found in low amounts. Sodium, iron and aluminum were detected in trace quantities (0.01%). Manganese was not detected in the present study. The seeds were found to be important both for their nutrients and non-nutrients which determined the medicinal and nutritional value of the plant. PMID:26031031

  11. Inorganic Chemical Composition of Swimming Pools in Amman-Jordan

    Directory of Open Access Journals (Sweden)

    Bety Saqarat

    2012-10-01

    Full Text Available Monitoring was carried out during summer 2011 in three types of swimming pools in Amman-Jordan. Thirty six water samples, collected from three users type of swimming pools (adults, family and infants, were examined for its major ionic composition (HCO3-, Cl-, NO3-, SO4=, Ca+2, Mg+2, Na+, K+ and PO4+4 in addition to its BOD and COD content. All of the examined samples from the swimming pools water were acceptable according to the local and WHO standards. The type and number of users as well as the maintenance of the swimming pool water influenced the water quality. The results showed that there was a noticeable increase in NO3, PO4 and Cl than other ions. All of the examined samples from the swimming pools water were acceptable according to the local and WHO standards and although the water of the infant’s users changed frequently, it showed the highest concentration of most of the parameters and Adults’ pool showed the lowest.

  12. Chemical compositions and kinematics of the Hercules stream

    CERN Document Server

    Ramya, P; Lambert, David L; Musthafa, M M

    2016-01-01

    An abundance analysis is reported of 58 K giants identified by Famaey et al. (2005) as highly probable members of the Hercules stream selected from stars north of the celestial equator in the Hipparcos catalogue. The giants have compositions spanning the interval [Fe/H] from $-$0.17 to $+$0.42 with a mean value of $+$0.15 and relative elemental abundances [El/Fe] representative of the Galactic thin disc. Selection effects may have biassed the selection from the Hipparcos catalogue against the selection of metal-poor stars. Our reconsideration of the recent extensive survey of FG dwarfs which included metal-poor stars (Bensby et al. 2014) provides a [Fe/H] distribution for the Hercules stream which is similar to that from the 58 giants. It appears that the stream is dominated by metal-rich stars from the thin disc. Suggestions in the literature that the stream includes metal-poor stars from the thick disc are discussed.

  13. Chemical Composition and Biological Activities of Gerbera anandria

    Directory of Open Access Journals (Sweden)

    Fa He

    2014-04-01

    Full Text Available Gerbera anandria (Compositae was extracted with 75% ethanol and the residue was fractionated using light petroleum, chloroform and ethyl acetate. The constituents of the extracts were separated by column chromatography employing solvents of different polarity. Column chromatography of the light petroleum fraction resulted in the isolation of methyl hexadecanoate, while the chloroform fraction afforded xanthotoxin, 2-hydroxy-6-methylbenzoic acid, 7-hydroxy-1(3H-isobenzofuranone, a mixture of β-sitosterol and stigmasterol, and 8-methoxysmyrindiol and the ethyl acetate fraction gave gerberinside, apigenin-7-O-β-d-glucopyranoside and quercetin. A new coumarin, 8-methoxysmyrindiol, was found. The chemical structures of the isolated compounds were established by MS and NMR (HSQC, HMBC. Free radical scavenging and cytotoxic activities of crude extracts and 8-methoxysmyrindiol were further investigated. The ethyl acetate phase exerted the strongest DPPH free radical scavenging activity in comparison to the other fractions. The coumarin 8-methoxysmyrindiol demonstrated cytotoxicity against multiple human cancer cell lines, with the highest potency in HepG2 cells.

  14. The chemical compositions of RR Lyrae type c variable stars

    Energy Technology Data Exchange (ETDEWEB)

    Govea, Jose; Gomez, Thomas; Sneden, Christopher [Department of Astronomy and McDonald Observatory, The University of Texas, Austin, TX 78712 (United States); Preston, George W., E-mail: jgovea@utexas.edu, E-mail: chris@verdi.as.utexas.edu, E-mail: iii@ociw.edu [The Observatories of the Carnegie Institution of Washington, Pasadena, CA 91101 (United States)

    2014-02-20

    We present a detailed chemical abundance study of eight RR Lyrae variable stars of subclass c (RRc). The target RRc stars chosen for study exhibit 'Blazhko-effect' period and amplitude modulations to their pulsational cycles. Data for this study were gathered with the echelle spectrograph of the 100 inch du Pont telescope at Las Campanas Observatory. Spectra were obtained throughout each star's pulsation cycle. Atmospheric parameters—effective temperature, surface gravity, microturbulent velocity, and metallicity—were derived at multiple phase points. We found metallicities and element abundance ratios to be constant within observational uncertainties over the pulsational cycles of all stars. Moreover, the α-element and Fe-group abundance ratios with respect to iron are consistent with other horizontal-branch members (RRab, blue and red non-variables). Finally, we have used the [Fe/H] values of these eight RRc stars to anchor the metallicity estimates of a large-sample RRc snapshot spectroscopic study being conducted with the same telescope and instrument combination employed here.

  15. Chemical composition, therapeutic potential and perspectives of Foeniculum vulgare

    Directory of Open Access Journals (Sweden)

    Chanchal Garga

    2009-01-01

    Full Text Available Foeniculum vulgare is a widely distributed plant in most tropical and subtropical countries and have long been used in folk medicines to treat obstruction of the liver, spleen and gall bladder and for digestive complaints such as colic, indigestion, nausea and flatulence. In recent years the interest in this plant has increased considerably with substantial progress on its chemical and pharmacological properties. This review discusses the current knowledge of its chemistry, the various compounds isolated and pharamcological studies conducted. These studies carried out with the extracts and volatile oil support most of the reports of using this plant in folk medicines. However, well controlled, double-binding clinical trials are lacking. Several compounds including trans-anethole, estragole, fenchone and polyphenolics were isolated from this plant and some of these interact with potential mechanisms of the body. Together this data strongly supports the view that this plant has potential beneficial therapeutic actions in the management of bacterial and fungal infections, colic pain and lipid peroxidation.

  16. Antimicrobial, antioxidant activities and chemical composition of selected Thai spices

    Directory of Open Access Journals (Sweden)

    Juraithip Wungsintaweekul

    2010-12-01

    Full Text Available Nine volatile oils and six methanol extracts from Ocimum americanum, O. basilicum, O. sanctum, Citrus hystrix,Alpinia galanga, Curcuma zedoaria, Kaempferia parviflora and Zingiber cassumunar were assessed for antimicrobial andantioxidant activities. The volatile oils and extracts were investigated against eight bacteria and three fungi. The resultsillustrated that O. americanum volatile oil exhibited broad spectrum activity against tested bacteria with the MICs ranging1.4-3.6 mg/ml and Candida spp. with the MICs ranging from 0.5-0.6 mg/ml. The O. sanctum volatile oil showed a considerableactivity against only Candida spp. with the MICs ranging from 0.8-1.4 mg/ml. Interestingly, growth of Mycobacteriumphlei was inhibited by the volatiles of O. americanum, C. hystrix peel, and C. zedoaria with MIC of 1.7, 3.5 and 1.2 mg/ml,respectively. For antioxidant activity evaluation, the methanol extracts of C. hystrix (leaf and peel and K. parviflora hadpotent antioxidant activity by the radical-scavenging DPPH method with IC50 of 24.6, 66.3 and 61.5 mg/ml, respectively.GC-MS analysis revealed the typical chemical profiles of the volatile oils. The major component showed the characteristicsof the volatile oils and was probably responsible for the antimicrobial effect.

  17. Conical intersection seams in polyenes derived from their chemical composition

    Science.gov (United States)

    Nenov, Artur; de Vivie-Riedle, Regina

    2012-08-01

    The knowledge of conical intersection seams is important to predict and explain the outcome of ultrafast reactions in photochemistry and photobiology. They define the energetic low-lying reachable regions that allow for the ultrafast non-radiative transitions. In complex molecules it is not straightforward to locate them. We present a systematic approach to predict conical intersection seams in multifunctionalized polyenes and their sensitivity to substituent effects. Included are seams that facilitate the photoreaction of interest as well as seams that open competing loss channels. The method is based on the extended two-electron two-orbital method [A. Nenov and R. de Vivie-Riedle, J. Chem. Phys. 135, 034304 (2011)], 10.1063/1.3608924. It allows to extract the low-lying regions for non-radiative transitions, which are then divided into small linear segments. Rules of thumb are introduced to find the support points for these segments, which are then used in a linear interpolation scheme for a first estimation of the intersection seams. Quantum chemical optimization of the linear interpolated structures yields the final energetic position. We demonstrate our method for the example of the electrocyclic isomerization of trifluoromethyl-pyrrolylfulgide.

  18. Conical intersection seams in polyenes derived from their chemical composition

    Energy Technology Data Exchange (ETDEWEB)

    Nenov, Artur; Vivie-Riedle, Regina de [Department Chemie, Ludwig-Maximilians-Univerisitaet, Muenchen Butenandtstr. 11, 81377 Muenchen (Germany)

    2012-08-21

    The knowledge of conical intersection seams is important to predict and explain the outcome of ultrafast reactions in photochemistry and photobiology. They define the energetic low-lying reachable regions that allow for the ultrafast non-radiative transitions. In complex molecules it is not straightforward to locate them. We present a systematic approach to predict conical intersection seams in multifunctionalized polyenes and their sensitivity to substituent effects. Included are seams that facilitate the photoreaction of interest as well as seams that open competing loss channels. The method is based on the extended two-electron two-orbital method [A. Nenov and R. de Vivie-Riedle, J. Chem. Phys. 135, 034304 (2011)]. It allows to extract the low-lying regions for non-radiative transitions, which are then divided into small linear segments. Rules of thumb are introduced to find the support points for these segments, which are then used in a linear interpolation scheme for a first estimation of the intersection seams. Quantum chemical optimization of the linear interpolated structures yields the final energetic position. We demonstrate our method for the example of the electrocyclic isomerization of trifluoromethyl-pyrrolylfulgide.

  19. Chemical modelling of pore water composition from PFBC residues

    International Nuclear Information System (INIS)

    The concentration of trace elements varies depending on the source of the coal and also due to the combustion process used. Mercury is one important element among the trace elements in the coal residues, generally recognised as potentially harmful to the biological system. To predict the pore water concentrations of mercury and other important constituents leached from coal combustion residues disposal sites, mechanistic data on chemical reactions are required. The present study is an application of a basially thermodynamical approach using the geochemical code EQ3NR. The presence of discrete solid phases that control the aqueous concentrations of major elements such as aluminium, calcium and silicon are identified. Solid phases are modelled in equilibrium with a hypothetical pore water at a pH range of 7-11. In this study the thermodynamic database of EQ3NR has been complemented with data for cadmium, mercury and lead taken from the OECD/NEA Thermodynamic Database and from a compilation made by Lindsay. Possible solubility limiting phases for the important trace elements arsenic, cadmium, chromium, copper, mercury, nickel and lead have been identified. Concentrations of these trace elements as a function of pH in the hypothetical pore water were calculated using mechanistic thermodynamial data. The thermodynamical approach in this study seems justified because most solid residues that are either present or expected to form during weathering have relatively fast precipitation/dissolution kinetics. (21 refs., 18 figs., 5 tabs.)

  20. The chemical composition of Galactic ring nebulae around massive stars

    CERN Document Server

    Esteban, C; Morisset, C; Garcia-Rojas, J

    2016-01-01

    We present deep spectra of ring nebulae associated with Wolf-Rayet (WR) and O-type stars: NGC 6888, G2.4+1.4, RCW 58, S 308, NGC 7635 and RCW 52. The data have been taken with the 10m Gran Telescopio Canarias and the 6.5m Clay Telescope. We extract spectra of several apertures in some of the objects. We derive C$^{++}$ and O$^{++}$ abundances from faint recombination lines in NGC 6888 and NGC 7635, permitting to derive their C/H and C/O ratios and estimate the abundance discrepancy factor (ADF) of O$^{++}$. The ADFs are larger than the typical ones of normal HII regions but similar to those found in the ionised gas of star-forming dwarf galaxies. We find that chemical abundances are rather homogeneous in the nebulae where we have spectra of several apertures: NGC 6888, NGC 7635 and G2.4+1.4. We obtain very high values of electron temperature in a peripheral zone of NGC 6888, finding that shock excitation can reproduce its spectral properties. We find that all the objects associated with WR stars show N enrich...

  1. Application of chemical vapor composites (CVC) to terrestrial thermionics

    International Nuclear Information System (INIS)

    Terrestrial flame fired thermionics took a great leap forward in the earlier 1980's with the development of reliable long-lived hot shells. These results were presented by Goodale (1981). The hot shell protects the fractory emitter from oxidizing in the combustion environment. In earlier efforts with supralloys emitters it was found that superalloys were poor thermionic emitters since they operated at too low a temperature for practical and economical use as discussed by Huffman (1978). With the development of Chemical Vapor Deposited (CVD) silicon carbide and CVD tungsten, it became possible to fabricate long-lived thermionic converters. These results were shown by Goodale (1980). Further improvements were achieved with the use of oxygen additives on the electrodes. These developments made thermionics attractive for topping a power plant or as the energy conversion part of a cogeneration plant as described by Miskolczy (1982) and Goodale (1983). The feasibility of a thermonic steam boiler and a thermionic topped gas turbine plant become a possibility, as shown by Miskolczy (1980). copyright 1995 American Institute of Physics

  2. Chemical Composition of Different Botanical Origin Honeys Produced by Sicilian Black Honeybees (Apis mellifera ssp. sicula).

    Science.gov (United States)

    Mannina, Luisa; Sobolev, Anatoly P; Di Lorenzo, Arianna; Vista, Silvia; Tenore, Gian Carlo; Daglia, Maria

    2015-07-01

    In 2008 a Slow Food Presidium was launched in Sicily (Italy) for an early warning of the risk of extinction of the Sicilian native breed of black honeybee (Apis mellifera L. ssp sicula). Today, the honey produced by these honeybees is the only Sicilian honey produced entirely by the black honeybees. In view of few available data regarding the chemical composition of A. mellifera ssp. sicula honeys, in the present investigation the chemical compositions of sulla honey (Hedysarum coronarium L.) and dill honey (Anethum graveolens L.) were studied with a multimethodological approach, which consists of HPLC-PDA-ESI-MSn and NMR spectroscopy. Moreover, three unifloral honeys (lemon honey (obtained from Citrus limon (L.) Osbeck), orange honey (Citrus arantium L.), and medlar honey (Eriobotrya japonica (Thunb.) Lindl)), with known phenol and polyphenol compositions, were studied with NMR spectroscopy to deepen the knowledge about sugar and amino acid compositions. PMID:25730368

  3. Chemical composition of a sample of bright solar-metallicity stars

    CERN Document Server

    Caffau, E; Steffen, M; Bonifacio, P; Strassmeier, K G; Gallagher, A; Faraggiana, R; Sbordone, L

    2015-01-01

    We present a detailed analysis of seven young stars observed with the spectrograph SOPHIE at the Observatoire de Haute-Provence for which the chemical composition was incomplete or absent in the literature. For five stars, we derived the stellar parameters and chemical compositions using our automatic pipeline optimized for F, G, and K stars, while for the other two stars with high rotational velocity, we derived the stellar parameters by using other information (parallax), and performed a line-by-line analysis. Chromospheric emission-line fluxes from CaII are obtained for all targets. The stellar parameters we derive are generally in good agreement with what is available in the literature. We provide a chemical analysis of two of the stars for the first time. The star HIP 80124 shows a strong Li feature at 670.8 nm implying a high lithium abundance. Its chemical pattern is not consistent with it being a solar sibling, as has been suggested.

  4. Chemical composition of inks of diverse marine molluscs suggests convergent chemical defenses.

    Science.gov (United States)

    Derby, Charles D; Kicklighter, Cynthia E; Johnson, P M; Zhang, Xu

    2007-05-01

    Some marine molluscs, notably sea hares, cuttlefish, squid, and octopus, release ink when attacked by predators. The sea hare Aplysia californica releases secretions from the ink gland and opaline gland that protect individuals from injury or death from predatory spiny lobsters through a combination of mechanisms that include chemical deterrence, sensory disruption, and phagomimicry. The latter two mechanisms are facilitated by millimolar concentrations of free amino acids (FAA) in sea hare ink and opaline, which stimulate the chemosensory systems of predators, ultimately leading to escape by sea hares. We hypothesize that other inking molluscs use sensory disruption and/or phagomimicry as a chemical defense. To investigate this, we examined concentrations of 21 FAA and ammonium in the defensive secretions of nine species of inking molluscs: three sea hares (Aplysia californica, Aplysia dactylomela, Aplysia juliana) and six cephalopods (cuttlefish: Sepia officinalis; squid: Loligo pealei, Lolliguncula brevis, Dosidicus gigas; octopus: Octopus vulgaris, Octopus bimaculoides). We found millimolar levels of total FAA and ammonium in these secretions, and the FAA in highest concentration were taurine, aspartic acid, glutamic acid, alanine, and lysine. Crustaceans and fish, which are major predators of these molluscs, have specific receptor systems for these FAA. Our chemical analysis supports the hypothesis that inking molluscs have the potential to use sensory disruption and/or phagomimicry as a chemical defense. PMID:17393278

  5. Chemical composition and content of essential oil from the bud of cultivated Turkish clove

    Directory of Open Access Journals (Sweden)

    Kollmannsberger, H.

    2007-05-01

    Full Text Available In this study, clove bud oil, which was cultivated in the Mediterranean region of Turkey, was provided from a private essential oil company in Turkey. Essential oil from clove (Syzygium aromaticum L. was obtained from steam-distillation method, and its chemical composition was analyzed by GC and GC-MS. The results showed that the essential oils mainly contained about 87.00% eugenol, 8.01% eugenyl acetate and 3.56% β-Caryophyllene. The chemical composition of the Turkish clove bud oil was comparable to those of trees naturally grown in their native regions.

  6. Chemical composition and antimicrobial activity of the essential oil from leaves of Algerian Melissa officinalis L.

    OpenAIRE

    Abdellatif, Fahima; Boudjella, Hadjira; Zitouni, Abdelghani; Hassani, Aicha

    2014-01-01

    The essential oil obtained from leaves of Melissa officinalis L. (Family of Lamiaceae) growing in Algeria, was investigated for its chemical composition and in vitro antimicrobial activity. The chemical composition was determined by hydro-distillation and analyzed by GC/MS and GC-FID. Sixty-three compounds were identified in the essential oil, representing 94.10 % of the total oil and the yields were 0.34 %. The major component was geranial (44.20 %). Other predominant components were neral (...

  7. Chemical composition and content of essential oil from the bud of cultivated Turkish clove

    OpenAIRE

    Kollmannsberger, H.; Nitz, S.; Ertaş, M.; Alma, M. H.

    2007-01-01

    In this study, clove bud oil, which was cultivated in the Mediterranean region of Turkey, was provided from a private essential oil company in Turkey. Essential oil from clove (Syzygium aromaticum L.) was obtained from steam-distillation method, and its chemical composition was analyzed by GC and GC-MS. The results showed that the essential oils mainly contained about 87.00% eugenol, 8.01% eugenyl acetate and 3.56% β-Caryophyllene. The chemical composition of the Turkish clove bud oil was com...

  8. Effect of irradiation on the chemical composition of hot dogs in Syria

    International Nuclear Information System (INIS)

    Chemical composition including moisture, ash, proteins, lipids, and ph value of the hot dogs irradiated with 5, 10, 15, 20 kGy were studied in comparative with the control sample. The study shows that the changes caused by irradiation of food refer to the changes in the food itself and the effects of irradiation on the microorganism pollutants. Irradiation does not change the basic composition of food, and the chemical changes are referred to the ions coming from irradiation or to the excited molecules. (author)

  9. The Chemical Composition and Biological Properties of Coconut (Cocos nucifera L. Water

    Directory of Open Access Journals (Sweden)

    Yan Fei Ng

    2009-12-01

    Full Text Available Coconut water (coconut liquid endosperm, with its many applications, is one of the world’s most versatile natural product. This refreshing beverage is consumed worldwide as it is nutritious and beneficial for health. There is increasing scientific evidence that supports the role of coconut water in health and medicinal applications. Coconut water is traditionally used as a growth supplement in plant tissue culture/micropropagation. The wide applications of coconut water can be justified by its unique chemical composition of sugars, vitamins, minerals, amino acids and phytohormones. This review attempts to summarise and evaluate the chemical composition and biological properties of coconut water.

  10. Evaluation of beetroot (Beta vulgaris L.) leaves during its developmental stages: a chemical composition study

    OpenAIRE

    Polyana Batoqui França Biondo; Joana Schuelter Boeing; Érica Oliveira Barizão; Nilson Evelazio de Souza; Makoto Matsushita; Claudio Celestino de Oliveira; Marcela Boroski; Jesuí Vergílio Visentainer

    2014-01-01

    Beetroot leaves (Beta vulgaris L.) are commonly cut off and discarded before using its bulb due to lack of knowledge of how to use them. Aiming at using these leaves, in the present study, in natura and dehydrated beetroot leaves were chemically characterized in terms of fatty acid composition, proximate composition, minerals, total phenolic compounds (TPC), and antioxidant activity by DPPH• in different stages (60, 80, and 100 days) of development. The beetroot leaves showed significant leve...

  11. The Chemical Composition and Nitrogen Distribution of Chinese Yak (Maiwa) Milk

    OpenAIRE

    John Shi; Jun Xue; Jinju Cheng; Ying Ma; Qiming Li; Jiaqi Wang; Haimei Li

    2011-01-01

    The paper surveyed the chemical composition and nitrogen distribution of Maiwa yak milk, and compared the results with reference composition of cow milk. Compared to cow milk, yak milk was richer in protein (especially whey protein), essential amino acids, fat, lactose and minerals (except phosphorus). The contents of some nutrients (total protein, lactose, essential amino acids and casein) were higher in the warm season than in the cold season. Higher ratios of total essential amino acids/to...

  12. Determination of the Amino Acid and Chemical Composition of Canned Smoked Mussels (Mytilus galloprovincialis, L.)

    OpenAIRE

    Şengör, Gülgün F.; Gün, Hüseyin; Kalafatoğlu, Hanife

    2008-01-01

    In this research smoking and canning techniques were applied to cultured mussels (Mytilus galloprovincialis, L.) from the Çanakkkale Strait in Eceabat, Turkey. Mussels that were smoked by liquid and traditional methods were canned in different sauces. The chemical composition and amino acid composition of the canned smoked mussels were determined by the results of laboratory analyses. As a result of smoking and canning mussels, a food with high nutritional value was obtained. It was determine...

  13. Isotopic and chemical composition of submarine geothermal gases from the Bay of Plenty, New Zealand

    International Nuclear Information System (INIS)

    Gas samples collected from the ocean floor near Whale Island, Bay of Plenty, New Zealand, are composed of carbon dioxide, methane, hydrogen, and air. The methane has an isotopic composition of delta13C(PDB) = -280/00 and deltaD(SMOW) = -1250/00. The isotopic and chemical composition show that the gases are of geothermal origin and similar to gas evolved from Whale Island hot springs

  14. [The structure and chemical composition of the femur after different metal alloys implantation

    OpenAIRE

    Zaitseva N.V.

    2015-01-01

    Background. Osteointegration is a key factor for successful implant ingrowth. It depends on quality of bone, lack of initial stability, excessive loading, loosening or fracture of screw, and fracture of implant itself. Other factors that can affect osteointegration are implant composition and features of implant surface. Objective. The aim was to study the structure and chemical composition of an injured bone by scanning electron microscopy at different times after the implantation of metal a...

  15. Chemical composition and anti-inflammatory effects of essential oil from Hallabong flower

    OpenAIRE

    Kim, Min-Jin; Yang, Kyong-Wol; Kim, Sang Suk; Park, Suk Man; Park, Kyung Jin; Kim, Kwang Sik; Choi, Young Hun; Cho, Kwang Keun; Lee, Nam Ho; Hyun, Chang-Gu

    2013-01-01

    A number of essential oils derived from plants are claimed to have several medicinal functions, including anti-cancer and anti-inflammation effects. However, the chemical composition and biological activities of flower-derived components have not been sufficiently characterized. Therefore, we investigated the composition of essential oils from Hallabong flower [(Citrus unshiu Marcov × Citrus sinensis Osbeck) × Citrus reticulata Blanco] and their anti-inflammatory effects. Hydro-dist ...

  16. Investigation of the chemical composition of mineral fractions of the Tsarev chondrite

    Energy Technology Data Exchange (ETDEWEB)

    Semenova, L.F.; Fisenko, A.V.; Kashkarova, V.G.; Melnikova, L.N.; Bezrogova, E.V.; Pomytkina, V.A.; Lavrukhina, A.K.

    1984-01-01

    A selective-dissolution method was used to study the chemical composition of mineral fractions of the Tsarev chondrite. Redistributions of Na, K, and P were found in mineral fractions of L-chondrites which have experienced different degrees of impact metamorphism. It is shown that the normative composition of inclusions in olivine in the Tsarev chondrite is characterized by a high content of diopside and anorthite components. 24 references.

  17. EFFECT OF CHEMICAL TREATMENT ON RICE HUSK (RH) REINFORCED POLYETHYLENE (PE) COMPOSITES

    OpenAIRE

    Md. Rezaur Rahman,; Md Nazrul Islam; Md. Monimul Huque; Sinin Hamdan

    2010-01-01

    In this study rice husk reinforced polyethylene composites and their test specimens were manufactured using a single screw extruder and an injection molding machine, respectively. Raw rice husk was chemically treated with benzene diazonium salt in alkali, acidic, and neutral media, in order to improve in the mechanical properties. The mechanical properties of the composites prepared from alkaline media treated rice husk were found to increase substantially compared to those of acidic media, n...

  18. Chemical composition of atmospheric aerosols between Moscow and Vladivostok

    Directory of Open Access Journals (Sweden)

    S. Kuokka

    2007-05-01

    Full Text Available The TROICA-9 expedition (Trans-Siberian Observations Into the Chemistry of the Atmosphere was carried out at the Trans-Siberian railway between Moscow and Vladivostok in October 2005. Measurements of aerosol physical and chemical properties were made from an observatory carriage connected to a passenger train. Black carbon (BC concentrations in fine particles (PM2.5, aerodynamic diameter <2.5 μm were measured with an aethalometer using a five-minute time resolution. Concentrations of inorganic ions and some organic compounds (Cl, NO3, SO42−, Na+, NH4+, K+, Ca2+, Mg2+, oxalate and methane sulphonate were measured continuously by using an on-line system with a 15-min time resolution. In addition, particle volume size distributions were determined for particles in the diameter range 3–850 nm using a 10-min. time resolution. The continuous measurements were completed with 24-h. PM2.5 filter samples which were stored in a refrigerator and later analyzed in chemical laboratory. The analyses included mass concentrations of PM2.5, ions, monosaccharide anhydrides (levoglucosan, galactosan and mannosan and trace elements (Al, As, Cd, Co, Cr, Cu, Fe, Mn, Ni, Pb, Sb, V and Zn. The mass concentrations of PM2.5 varied in the range of 4.3–34.8 μg m−3 with an average of 21.6 μg m−3. Fine particle mass consisted mainly of BC (average 27.6%, SO42− (13.0%, NH4+ (4.1%, and NO3 (1.4%. One of the major constituents was obviously also organic carbon which was not determined. The contribution of BC was high compared with other studies made in Europe and Asia. High concentrations of ions, BC and particle volume were observed between Moscow and roughly 4000 km east of it, as well as close to

  19. Quantification of glacial till chemical composition by reflectance spectroscopy

    International Nuclear Information System (INIS)

    Chemometric modelling of soil element concentrations from diffuse visible and near-infrared (VSWIR, 350–2500 nm) reflectance spectroscopic measurements holds potential for soil element analyses. Research has demonstrated it particularly for organic agricultural soils, yet little is known about the VSWIR response of glacial tills. Soils with low organic matter content developed on unstratified glacial materials were studied at two geologically similar sites on the mafic metavolcanic rocks of the Lapland Greenstone belt in northern Finland. The till samples (n = 217) were composed primarily of quartz, plagioclase and amphibole having less than 3% of clinochlore, talc and illite. VSWIR spectra of mineral powder (2 = 0.80–0.89) of several soil chemical elements such as Al (validation RMSE 1802 mg kg−1), Ba (5.85 mg kg−1), Co (0.86 mg kg−1), Cr (6.94 mg kg−1), Cu (2.54 mg kg−1), Fe (2088 mg kg−1), Mg (449.6 mg kg−1), Mn (0.82 mg kg−1), Ni (3.24 mg kg−1), V (4.88 mg kg−1), and Zn (0.80 mg kg−1). The electronic and vibrational molecular processes causing absorption might be responsible for accurate predictions of major elements such as Al, Fe and Mg. However, the concentrations of other major and trace elements could be predicted by the PLSR because they were cross-correlated to spectrally active soil elements or extraneous soil properties. Therefore, the applicability of the results is highly sample set specific. Further, the results show that in local scale studies at geologically fairly homogenous areas the limited spread of the data may restrict the use of the spectroscopic–chemometric approach. This paper demonstrates the capability of laboratory VSWIR spectroscopy for determining element concentrations of glacial tills. Further work should focus on overcoming the issues of sampling scale and understanding the causality for cross-correlation in quantification of the elements.

  20. Chemical composition of black-watered rivers in the Amazons Region (Brazil)

    Energy Technology Data Exchange (ETDEWEB)

    Horbe, Adriana M.C.; Santos, Ana G. da Silva [Universidade Federal do Amazonas (UFAM), Manaus, AM (Brazil). Dept. de Geociencias], e-mail: ahorbe@ufam.edu.br

    2009-07-01

    Most investigations addressing Amazonian water chemistry are focused on the Solimoes, Amazonas and Negro rivers. Knowledge of the chemical composition of their smaller tributaries is restricted to some few, punctual data. The smaller rivers, that only present inputs from their catchments, are very important to understand the overall mechanisms controlling the chemistry of larger rivers of the region. With this objective the chemical composition of the principal Solimoes river black-watered tributaries in the western Brazilian Amazon during the low water period were determined. The data reveal the black water chemical composition to be highly variable and strongly influenced by the local geological environment: the Badajos basin being chemically more diluted; the Coari basin presenting higher SiO{sub 2} contents, as well as smaller lakes having higher pH, conductivity, Ca{sup 2+}, Mg{sup 2+} and Sr, yet not as much as those found in the Solimoes river. The chemical composition of these waters is compatible with the low physical erosion and the region's highly leached tropical environment from which most soluble elements were quickly removed. (author)

  1. Chemical composition of black-watered rivers in the Amazons Region (Brazil)

    International Nuclear Information System (INIS)

    Most investigations addressing Amazonian water chemistry are focused on the Solimoes, Amazonas and Negro rivers. Knowledge of the chemical composition of their smaller tributaries is restricted to some few, punctual data. The smaller rivers, that only present inputs from their catchments, are very important to understand the overall mechanisms controlling the chemistry of larger rivers of the region. With this objective the chemical composition of the principal Solimoes river black-watered tributaries in the western Brazilian Amazon during the low water period were determined. The data reveal the black water chemical composition to be highly variable and strongly influenced by the local geological environment: the Badajos basin being chemically more diluted; the Coari basin presenting higher SiO2 contents, as well as smaller lakes having higher pH, conductivity, Ca2+, Mg2+ and Sr, yet not as much as those found in the Solimoes river. The chemical composition of these waters is compatible with the low physical erosion and the region's highly leached tropical environment from which most soluble elements were quickly removed. (author)

  2. HONEYDEW HONEY: CORRELATIONS BETWEEN CHEMICAL COMPOSITION, ANTIOXIDANT CAPACITY AND ANTIBACTERIAL EFFECT

    OpenAIRE

    OTILIA BOBIS; L. MARGHITAS; IULIA KRISZTINA RINDT; MIHAELA NICULAE; D. DEZMIREAN

    2013-01-01

    Selected physico-chemical parameters, total polyphenols, flavonoids, antioxidant and antibacterial activity of honeydew honey samples from Romanian were determined. Regarding the chemical composition, analysed honey samples framed in this type of honey, phenolic content, determined as gallic acid equivalents, presented a mean value of 116.45mg GAE/100 g honey. Total flavonoid content expressed as quercetin equivalents, was 1.53 mg in honeydew honey. Antioxidant activity expressed as % inhibit...

  3. Chemical Composition, Antimicrobial and Antioxidant Activities of Hyssop (Hyssopus officinalis L.) Essential Oil

    OpenAIRE

    KIZIL, Süleyman; HAŞİMİ, Nesrin; TOLAN, Veysel; Ersin KILININÇ; Karataş, Hakan

    2010-01-01

    The essential oil of hyssop is widely used in food, pharmaceutical and cosmetic industries throughout the world. Therefore, it is very important to know the chemical characteristics of the oil for economic use and enhanced performance of the end products. This study was carried out to determine antimicrobial and antioxidant activities of the essential oil of Hyssopus officinalis (L.) (Lamiaceae) collected from wild in the Southeast Anatolian, Turkey. Chemical compositions of hydrodistilled es...

  4. The detailed chemical composition of the terrestrial planet host Kepler-10

    OpenAIRE

    Liu, F.; Yong, D.; Asplund, M.; Ramirez, I.; Melendez, J.; Gustafsson, B.; Howes, L. M.; Roederer, I. U.; Lambert, D. L.; Bensby, T.

    2015-01-01

    Chemical abundance studies of the Sun and solar twins have demonstrated that the solar composition of refractory elements is depleted when compared to volatile elements, which could be due to the formation of terrestrial planets. In order to further examine this scenario, we conducted a line-by-line differential chemical abundance analysis of the terrestrial planet host Kepler-10 and fourteen of its stellar twins. Stellar parameters and elemental abundances of Kepler-10 and its stellar twins ...

  5. Hanford enhanced waste glass characterization. Influence of composition on chemical durability

    Energy Technology Data Exchange (ETDEWEB)

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

    2016-06-01

    This report provides a review of the complete high-level waste (HLW) and low-activity waste (LAW) data sets for the glasses recently fabricated at Pacific Northwest National Laboratory and characterized at Savannah River National Laboratory (SRNL). The review is from the perspective of relating the chemical durability performance to the compositions of these study glasses, since the characterization work at SRNL focused on chemical analysis and ASTM Product Consistency Test (PCT) performance.

  6. 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...

  7. Structure and chemical composition of the dentin-enamel junction analyzed by Confocal Raman Microscopy

    Science.gov (United States)

    Desoutter, A.; Salehi, H.; Slimani, A.; Marquet, P.; Jacquot, B.; Tassery, H.; Cuisinier, F. J. G.

    2014-02-01

    The structure and chemical composition of the human dentin-enamel junction (DEJ) was studied using confocal Raman microscopy - a chemical imaging technique. Slices of non-fixed, sound teeth were prepared with an Isomet diamond saw and scanned with Witec Alpha300R system. The combination of different characteristics peaks of phosphate, carbonate and organic matrix (respectively 960, 1072 and 1545 cm-1), generates images representing the chemical composition of the DEJ area. Images are also calculated using peak ratios enabling precise determination of the chemical composition across the DEJ. Then, with two characterized peaks, different pictures are calculated to show the ratio of two components. The images of the spatial distribution of mineral phosphate (960cm-1) to organic matrix (1545 cm-1) ratios, mineral carbonates (1072cm-1) to mineral phosphate ratios; and mineral carbonates to organic matrix ratios were reconstructed. Cross sectional and calculated graphic profile show the variations of the different chemical component ratios through the enamel and the dentin. Phosphate to organic ratio shows an accumulation of organic material under the enamel surface. The cross sectional profile of these pictures shows a high phosphate content compared to enamel in the vicinity of the DEJ. The Confocal Raman imaging technique can be used to further provide full chemical imaging of tooth, particularly of the whole DEJ and to study enamel and dentin decay.

  8. Metal Oxide Nanoparticles: The Importance of Size, Shape, Chemical Composition, and Valence State in Determining Toxicity

    Science.gov (United States)

    Dunnick, Katherine

    Nanoparticles, which are defined as a structure with at least one dimension between 1 and 100 nm, have the potential to be used in a variety of consumer products due to their improved functionality compared to similar particles of larger size. Their small size is associated with increased strength, improved catalytic properties, and increased reactivity; however, their size is also associated with increased toxicity in vitro and in vivo. Numerous toxicological studies have been conducted to determine the properties of nanomaterials that increase their toxicity in order to manufacture new nanomaterials with decreased toxicity. Data indicates that size, shape, chemical composition, and valence state of nanomaterials can dramatically alter their toxicity profile. Therefore, the purpose of this dissertation was to determine how altering the shape, size, and chemical composition of various metal oxide nanoparticles would affect their toxicity. Metal oxides are used in variety of consumer products, from spray-sun screens, to food coloring agents; thus, understanding the toxicity of metal oxides and determining which aspects affect their toxicity may provide safe alternatives nanomaterials for continued use in manufacturing. Tungstate nanoparticles toxicity was assessed in an in vitro model using RAW 264.7 cells. The size, shape, and chemical composition of these nanomaterials were altered and the effect on reactive oxygen species and general cytotoxicity was determined using a variety of techniques. Results demonstrate that shape was important in reactive oxygen species production as wires were able to induce significant reactive oxygen species compared to spheres. Shape, size, and chemical composition did not have much effect on the overall toxicity of these nanoparticles in RAW 264.7 cells over a 72 hour time course, implicating that the base material of the nanoparticles was not toxic in these cells. To further assess how chemical composition can affect toxicity

  9. Prediction of chemical contaminants and food compositions by near infrared spectroscopy

    Science.gov (United States)

    Prediction of Food Adulteration by Infrared Spectroscopy H. Zhuang Quality and Safety Assessment Research Unit, ARS-USDA, 950 College Station Road, Athens, GA 30605 Food adulteration, including both chemical contamination and composition alternation, has been one of major quality and/or safety c...

  10. Lantana montevidensis Essential Oil: Chemical Composition and Mosquito Repellent Activity against Aedes aegypti

    Science.gov (United States)

    The essential oil (EO) of Lantana montevidensis (Spreng.) Briq. (L. sellowiana Link & Otto) was investigated for its chemical composition and mosquito repellent activity. The essential oil obtained by hydrodistillation of aerial plant parts was analyzed by GC-FID and GC-MS. The major constituents we...

  11. Chemical composition and antispasmodic effect of Casimiroa pringlei essential oil on rat uterus.

    Science.gov (United States)

    Ponce-Monter, Héctor; Campos, María G; Pérez, Salud; Pérez, Cuauhtémoc; Zavala, Miguel; Macías, Arturo; Oropeza, Martha; Cárdenas, Norma

    2008-09-01

    The Casimiroa pringlei essential oil was analyzed to determine its chemical composition. Its effect on rat uterine smooth muscle was studied and compared with verapamil. Pure commercial piperitone, eucalyptol, and alpha-terpineol, the major constituents of C. pringlei essential oil, were tested on the uterine tonic contraction induced by high-potassium depolarizing solution (KCl 60 mM). PMID:18538506

  12. Discerning the Chemical Composition and Mutagenic Effects of Soy Biodiesel PM

    Science.gov (United States)

    Discerning the Chemical Composition and Mutagenic Effects of Soy Biodiesel PM David G. Nashab, Esra Mutluc, William T. Prestond, Michael D. Haysb, Sarah H. Warrenc, Charly Kingc, William P. Linakb, M. lan Gilmourc, and David M. DeMarinic aOak Ridge Institute for Science and Ed...

  13. Composite biomaterials with chemical bonding between hydroxyapatite filler particles and PEG/PBT copolymer matrix

    NARCIS (Netherlands)

    Liu, Qing; Wijn, de Joost R.; Blitterswijk, van Clemens A.

    1998-01-01

    In an effort to make composites from hydroxyapatite and a PEG/PBT copolymer (PolyactiveTM 70/30), chemical linkages were introduced between the filler particles and polymer matrix using hexamethylene diisocyanate as a coupling agent. Infrared spectra (IR) and thermal gravimetric analysis (TGA) confi

  14. Size-Resolved Volatility and Chemical Composition of Aged European Aerosol Measured During FAME-2008

    Science.gov (United States)

    Hildebrandt, L.; Mohr, C.; Lee, B.; Engelhart, G. J.; Decarlo, P. F.; Prevot, A. S.; Baltensperger, U.; Donahue, N. M.; Pandis, S. N.

    2008-12-01

    We present first results on the volatility and chemical composition of aged organic aerosol measured during the Finokalia Aerosol Measurement Experiment - 2008 (FAME-2008). Finokalia is located in the Southeast of Crete, Greece, and this remote site allows for the measurement of aged European aerosol as it is transported from Central to Southeastern Europe. We measured the volatility of the aerosol at Finokalia as a function of its size by combining several instruments. We used an Aerodyne quadrupole aerosol mass spectrometer (Q-AMS) to measure the size-resolved chemical composition of the particles, a scanning mobility particle sizer (SMPS) to measure the volume distribution of particles, and a thermodenuder system to induce changes in size and composition via moderate heating of the particles. The largest fraction of the non-refractory material in the aerosol sampled was ammonium sulfate and ammonium bisulfate, followed by organic material and a small contribution from nitrate. Most of the organic aerosol was highly oxidized, even after only a few days of transport over continental Europe. These highly oxidized organics had lower volatility than fresh primary or secondary aerosol measured in the laboratory. Significant changes in air-parcel trajectories and wind direction led to changes in the chemical composition of the sampled aerosol and corresponding changes of the volatility. These results allow the quantification of the effect of atmospheric processing on organic aerosol volatility and can be used as constraints for atmospheric Chemical Transport Models that predict the aerosol volatility.

  15. Control factors of chemical and isotopic composition of groundwater in Varadero- Cardenas region, Matanzas, Cuba

    International Nuclear Information System (INIS)

    Multivariate analysis was performed to isotopic and chemical composition of groundwater from the karstic aquifer of Varadero- Cardenas in order to define those factor controlling or influencing its variations in time and space. The research was part of a project sponsored by International of Atomic Energy aimed to improve aquifer management applying isotopic techniques

  16. Chemical composition and lipoxygenase activity in soybeans (Glycine max L. Merr.) submitted to gamma irradiation

    International Nuclear Information System (INIS)

    Soybeans are an important food due to their functional and nutritional characteristics. However, consumption by western populations is limited by the astringent taste of soybeans and their derivatives which results from the action of lipoxygenase, an enzyme activated during product processing. The aim of this study was to evaluate the effect of gamma irradiation on the chemical composition and specific activity of lipoxygenase in different soybean cultivars. Soybeans were stored in plastic bags and irradiated with doses of 2.5, 5 and 10 kGy. The chemical composition (moisture, protein, lipids, ashes, crude fiber, and carbohydrates) and lipoxygenase specific activity were determined for each sample. Gamma irradiation induced a small increase of protein and lipid content in some soybean cultivars, which did not exceed the highest content of 5% and 26%, respectively, when compared to control. Lipoxygenase specific activity decreased in the three cultivars with increasing gamma irradiation dose. In conclusion, the gamma irradiation doses used are suitable to inactivate part of lipoxygenase while not causing expressive changes in the chemical composition of the cultivars studied. - Highlights: • The gamma irradiation treatment reduces lipoxygenases activity of soybean. • Independently of soybean cultivar, treatment 10 kGy exhibited higher percentages of reduction of lipoxygenase. • Gamma irradiation interfered few in the chemical composition of soybean. • The lipid and protein content remained stable regardless of radiation dose applied to the soybean

  17. Spectroscopic characterization of the chemical composition of the potent sweetener Vartamil

    Science.gov (United States)

    Kolosova, T. E.; Prokhodchenko, L. K.; Pilipenko, V. V.; Suboch, V. P.

    2008-03-01

    The chemical composition of the potent sweetener Vartamil was characterized using spectral methods. It was demonstrated that Vartamil is a mixture of saccharose chloro derivatives, the main one of which is 4,1',6'-trichloro-4,1',6'-trideoxygalactosaccharose (Sucralose).

  18. Chemical composition and biological activity of the essential oil of rhizome of Zingiber zerumbet (L.) smith

    Science.gov (United States)

    Technical Abstract: The aim was designed to study the biological activity and chemical composition of essential oil of Zingiber zerumbet (L.) Smith. The essential oil extracted from the rhizome of the plant was analysed by gas chromatography-mass spectroscopy and its major components amounting t...

  19. Effects of extrusion cooking on the chemical composition and functional properties of dry bean powders

    Science.gov (United States)

    This study aimed to investigate the impacts of extrusion cooking on the chemical composition and functional properties of bean powders from four bean varieties. The raw bean powders were extruded under eight different conditions, and the extrudates were then dried and ground (particle size = 0.5 mm)...

  20. Control device changes the chemical composition and temperature of the environment

    Directory of Open Access Journals (Sweden)

    І.Л. Трофімов

    2008-01-01

    Full Text Available  The device of control change chemical composition and ambient temperature is developed, by means mathematical model the principle of his action is grounded. The value of operating parameters basic for the given device is resulted, the row dependence is built, that his work is characterized.

  1. Chemical composition and cell wall polysaccharide degradability of pith and rind tissues from mature maize internodes

    Science.gov (United States)

    Our study was undertaken to identify tissue-specific biochemical traits that may be targeted in breeding programs for improving forage digestibility. We compared cell wall chemical composition and 24- and 96-h in vitro degradabilities in separated pith and rind tissues from six maize inbred lines. A...

  2. Effect of chemical treatment of Kevlar fibers on mechanical interfacial properties of composites.

    Science.gov (United States)

    Park, Soo-Jin; Seo, Min-Kang; Ma, Tae-Jun; Lee, Douk-Rae

    2002-08-01

    In this work, the effects of chemical treatment on Kevlar 29 fibers have been studied in a composite system. The surface characteristics of Kevlar 29 fibers were characterized by pH, acid-base value, X-ray photoelectron spectroscopy (XPS), and FT-IR. The mechanical interfacial properties of the final composites were studied by interlaminar shear strength (ILSS), critical stress intensity factor (K(IC)), and specific fracture energy (G(IC)). Also, impact properties of the composites were investigated in the context of differentiating between initiation and propagation energies and ductile index (DI) along with maximum force and total energy. As a result, it was found that chemical treatment with phosphoric acid solution significantly affected the degree of adhesion at interfaces between fibers and resin matrix, resulting in improved mechanical interfacial strength in the composites. This was probably due to the presence of chemical polar groups on Kevlar surfaces, leading to an increment of interfacial binding force between fibers and matrix in a composite system. PMID:16290785

  3. CHEMICAL COMPOSITION VARIABILITY IN THE Uncaria tomentosa (cat’s claw WILD POPULATION

    Directory of Open Access Journals (Sweden)

    Evelyn Maribel Condori Peñaloza

    2015-03-01

    Full Text Available Uncaria tomentosa (cat's claw is a vine widely distributed throughout the South-American rainforest. Many studies investigating the chemical composition of cat's claw have focused on the pentacyclic (POA and tetracyclic oxindole alkaloids (TOA, quinovic acid glycosides (QAG, and polyphenols (PPH. Nevertheless, it is still uncertain how environmental factors affect chemical groups. The aim of this work was to better understand the influence of environmental factors (geographic origin, altitude, and season on cat's claw chemical composition. Stem bark, branches and leaf samples were extracted and analyzed by HPLC-PDA. The data obtained were explored by multivariate analysis (HCA and PCA. Higher amounts of oxindole alkaloids and PPH were found in leaves, followed by stem bark and branches. No clear relationship was verified among geographic origin or altitude and chemical composition, which remained unchanged regardless of season (dry or rainy. However, three oxindole alkaloid chemotypes were clearly recognized: chemotype I (POA with cis D/E ring junction; chemotype II (POA with trans D/E ring junction; and chemotype III (TOA. Thus, environmental factors appear to have only a minor influence on the chemical heterogeneity of the cat's claw wild population. Nevertheless, the occurrence of different chemotypes based on alkaloid profiles seems to be clear.

  4. EFFECT OF THERMAL TREATMENT ON THE CHEMICAL COMPOSITION AND MECHANICAL PROPERTIES OF BIRCH AND ASPEN

    Directory of Open Access Journals (Sweden)

    Duygu Kocaefe

    2008-05-01

    Full Text Available The high temperature treatment of wood is one of the alternatives to chemical treatment. During this process, the wood is heated to higher temperatures than those of conventional drying. The wood structure changes due to decomposition of hemicelluloses, ramification of lignin, and crystallization of cellulose. The wood becomes less hygroscopic. These changes improve the dimensional stability of wood, increase its resistance to micro-organisms, darken its color, and modify its hardness. However, wood also might loose some of its elasticity. Consequently, the heat treatment conditions have to be optimized. Therefore, it is important to understand the transformation of the chemical structure of wood caused by the treatment. In this study, the modification of the surface composition of the wood was followed with Fourier transform infrared spectroscopy (FTIR and inverse gas chromatography (IGC under different experimental conditions. The effect of maximum treatment temperatures on the chemical composition of Canadian birch and aspen as well as the correlations between their chemical transformation and different mechanical properties are presented. FTIR analysis results showed that the heat treatment affected the chemical composition of birch more compared to that of aspen. The results of IGC tests illustrated that the surfaces of the aspen and birch became more basic with heat treatment. The mechanical properties were affected by degradation of hemicellulose, ramification of lignin and cellulose crystallization.

  5. The use of sugarcane bagasse ash as an alternative local pozzolanic material: study of chemical composition

    International Nuclear Information System (INIS)

    The sugarcane bagasse ash is used as fuel in the boilers of the Kinana sugar factory in Sudan. The field observation and qualitative study of the ash revealed that it consisted of major amounts of carbon and organic materials; this is due to the incomplete combustion of bagasse fibers in boilers. Therefore, it became necessary to recondition the samples for use as pozzolana by re-ashing it. The study of chemical composition of the ash revealed that such byproducts are likely to be pozzolanic. Comparison between chemical compositions of Kinana sugarcane bagasse ash and the pulverized coal fly ashes (ASTM C 618 1999) shows that the composition of bagasse resembles that of Class F Coal Fly Ash, as the total of alumina, silica, and ferric oxide content is about 72 %. It may, behave like Class F Fly Ash, in its engineering properties. (author)

  6. Chemical composition and antibacterial activity of Opuntia ficus-indica f. inermis (cactus pear) flowers.

    Science.gov (United States)

    Ennouri, Monia; Ammar, Imene; Khemakhem, Bassem; Attia, Hamadi

    2014-08-01

    Opuntia ficus-indica f. inermis (cactus pear) flowers have wide application in folk medicine. However, there are few reports focusing on their biological activity and were no reports on their chemical composition. The nutrient composition and hexane extracts of Opuntia flowers at 4 flowering stages and their antibacterial and antifungal activities were investigated. The chemical composition showed considerable amounts of fiber, protein, and minerals. Potassium (K) was the predominant mineral followed by calcium (Ca), magnesium (Mg), sodium (Na), iron (Fe), and zinc (Zn). The main compounds in the various hexane extracts were 9.12-octadecadienoic acid (29-44%) and hexadecanoic acid (8.6-32%). The antibacterial activity tests showed that O. inermis hexane extracts have high effectiveness against Escherichia coli and Staphylococcus aureus, making this botanical source a potential contender as a food preservative or food control additive. PMID:24650181

  7. The effect of biological and chemical additives on the chemical composition and fermentation process of Dactylis glomerata silage

    Directory of Open Access Journals (Sweden)

    Jhonny E. Alba-Mejía

    2016-06-01

    Full Text Available This study was carried out to determine the chemical composition, silage quality and ensilability of ten cocksfoot cultivars using biological and chemical silage additives. The plant material was harvested from the first and second cut, cultivated at the Research Station of Fodder Crops in Vatín, Czech Republic. Wilted forage was chopped and ensiled in mini-silos with 3 replicates per treatment. The treatments were: 1 without additives, used as a control; 2 with bacterial inoculants; and 3 with chemical preservatives. The results indicated that the year factor (2012-2013 influenced significantly the chemical composition of the silage in both cuts. The use of biological inoculants reduced the content of crude fibre and acid detergent fibre; but it did not influence the content of neutral detergent fibre, in comparison with the control silage in both cuts. Furthermore, the application of biological inoculants reduced the concentration of lactic acid (LA and acetic acid (AA in contrast to the control silage in the first cut. Moreover, in the second cut the same values tended to be the opposite. Interestingly, ‘Amera’ was the unique variety that presented a high concentration of butyric acid (0.2% in comparison with other varieties in the first cut. In conclusion, the biological inoculants had a favourable effect on silage fermentation. Notably, only ‘Greenly’ and ‘Starly’ varieties from the first cut; and ‘Greenly’, ‘Sw-Luxor’, and ‘Otello’ varieties from the second cut were appropriate for ensiling because their pH-values; LA and AA concentrations were ideal according to the parameters of the fermentation process.

  8. Chemical composition measurements of the low activity waste (LAW) EPA-Series glasses

    International Nuclear Information System (INIS)

    In this report, the Savannah River National Laboratory provides chemical analysis results for a series of simulated low activity waste glasses provided by Pacific Northwest National Laboratory as part of an ongoing development task. The measured chemical composition data are reported and compared with the targeted values for each component for each glass. A detailed review showed no indications of errors in the preparation or measurement of the study glasses. All of the measured sums of oxides for the study glasses fell within the interval of 100.2 to 100.8 wt %, indicating recovery of all components. Comparisons of the targeted and measured chemical compositions showed that the measured values for the glasses met the targeted concentrations within 10% for those components present at more than 5 wt %.

  9. Chemical composition measurements of the low activity waste (LAW) EPA-Series glasses

    Energy Technology Data Exchange (ETDEWEB)

    Fox, K. [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL); Edwards, T. B. [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL)

    2016-03-01

    In this report, the Savannah River National Laboratory provides chemical analysis results for a series of simulated low activity waste glasses provided by Pacific Northwest National Laboratory as part of an ongoing development task. The measured chemical composition data are reported and compared with the targeted values for each component for each glass. A detailed review showed no indications of errors in the preparation or measurement of the study glasses. All of the measured sums of oxides for the study glasses fell within the interval of 100.2 to 100.8 wt %, indicating recovery of all components. Comparisons of the targeted and measured chemical compositions showed that the measured values for the glasses met the targeted concentrations within 10% for those components present at more than 5 wt %.

  10. Toxicological characterization of chemicals produced from laser irradiation of graphite composite materials

    International Nuclear Information System (INIS)

    One of the major potential hazards associated with laser machining of graphite composite materials is the toxic fumes and gases that are generated. When exposed to the intense energy of the laser beam, the organic polymer matrix of the composite material may decompose into various toxic by-products. To advance the understanding of the laser machining process from a health and safety viewpoint, this particular study consisted of the following steps: collect and analyze gaseous by-products generated during laser machining; collect particulates generated during laser machining and chemically extract them to determine the chemical species that may have absorbed or recondensed onto these particles; and review and evaluate the toxicity of the identified chemical species

  11. Chemical composition of glass and crystalline phases in coarse coal gasification ash

    Energy Technology Data Exchange (ETDEWEB)

    R.H. Matjie; Zhongsheng Li; Colin R. Ward; David French [Sasol Technology (Pty) Ltd., Sasolburg (South Africa)

    2008-05-15

    A procedure has been developed for determining the chemical composition and relative abundance of the amorphous or glassy material, as well as crystalline phases, present in coarse coal gasification ash, in order to assist in predicting the behaviour of the material in cement/brick/concrete applications. The procedure is based on a combination of quantitative X-ray diffraction (XRD), chemical analysis and electron microprobe studies. XRD analysis indicates that the clinker samples contain a number of crystalline high temperature phases, including anorthite, mullite, cristobalite, quartz and diopside. Quantitative evaluation using Rietveld-based techniques has been used to determine the percentages of both the individual crystalline phases and the glass component. These data were then combined with the chemistry of the crystalline phases and the overall chemical composition of the ash to estimate the chemical composition of the glass phase, which is typically the most abundant component present in the different materials. Although there is some degree of scatter, comparison between the inferred glass composition from XRD and bulk chemistry and actual data on the glass composition using electron microprobe techniques suggest that the two approaches are broadly consistent. The microprobe further indicates that a range of compositions are present in the glassy and crystalline components of the ashes, including Si-Al-rich glass, metakaolin and Fe-Ca-Mg-Ti phases, as well as quartz, anorthite and an aluminophosphate material. Electron microprobe and XRD studies also show that pyrrhotite (FeS), representing a high temperature transformation product of pyrite, is present in some clinker and partially burnt carbonaceous shale samples. 27 refs., 5 figs., 7 tabs.

  12. FY98 Final Report Initial Interfacial Chemical Control for Enhancement of Composite Material Strength; TOPICAL

    International Nuclear Information System (INIS)

    The U.S. Army Armament Research Development and Engineering Center (ARDEC) sponsored this research project to support the development of new self-assembled monolayer fiber coatings. These coatings can greatly increase the bond strength between the fiber and the resin matrix of a composite material. Composite ammunition components molded from such materials will exhibit higher strength than current materials, and will provide a major improvement in the performance of composites in military applications. Use of composite materials in military applications is desirable because of the lighter weight of the materials and their high strengths. The FY97 project investigated initial interfacial chemical control for enhancement of composite material strength. The core of the project was to modify the covalent interface of glass fibers (or other reinforcing fibers) to induce strong, uniform, defect-free adhesion between the fibers' surfaces and the polymer matrix. Installing a self-assembled monolayer tailored to the specific matrix resin accomplished this. Simply, the self-assembled monolayer modifies the fiber to make it appear to have the same chemical composition as the resin matrix. The self-assembled monolayer creates a receptive, hydrophobic interface that the thermoset resin (or polymer precursors) would wet more effectively, leading to a higher contact surface area and more efficient adhesion. The FY97 work phase demonstrated that it is possible to increase the adhesive strength, as well as increase the heat deflection temperature through the use of self-assembled monolayer

  13. Wood chemical composition in species of Cactaceae: the relationship between lignification and stem morphology.

    Science.gov (United States)

    Reyes-Rivera, Jorge; Canché-Escamilla, Gonzalo; Soto-Hernández, Marcos; Terrazas, Teresa

    2015-01-01

    In Cactaceae, wood anatomy is related to stem morphology in terms of the conferred support. In species of cacti with dimorphic wood, a unique process occurs in which the cambium stops producing wide-band tracheids (WBTs) and produces fibers; this is associated with the aging of individuals and increases in size. Stem support and lignification have only been studied in fibrous tree-like species, and studies in species with WBTs or dimorphic wood are lacking. In this study, we approach this process with a chemical focus, emphasizing the role of wood lignification. We hypothesized that the degree of wood lignification in Cactaceae increases with height of the species and that its chemical composition varies with wood anatomy. To test this, we studied the chemical composition (cellulose, hemicellulose, and lignin content) in 13 species (2 WBTs wood, 3 dimorphic, and 8 fibrous) with contrasting growth forms. We also analyzed lignification in dimorphic and fibrous species to determine the chemical features of WBTs and fibers and their relationship with stem support. The lignin contents were characterized by Fourier transform infrared spectroscopy and high performance liquid chromatography. We found that 11 species have a higher percentage (>35%) of lignin in their wood than other angiosperms or gymnosperms. The lignin chemical composition in fibrous species is similar to that of other dicots, but it is markedly heterogeneous in non-fibrous species where WBTs are abundant. The lignification in WBTs is associated with the resistance to high water pressure within cells rather than the contribution to mechanical support. Dimorphic wood species are usually richer in syringyl lignin, and tree-like species with lignified rays have more guaiacyl lignin. The results suggest that wood anatomy and lignin distribution play an important role in the chemical composition of wood, and further research is needed at the cellular level. PMID:25880223

  14. Wood chemical composition in species of Cactaceae: the relationship between lignification and stem morphology.

    Directory of Open Access Journals (Sweden)

    Jorge Reyes-Rivera

    Full Text Available In Cactaceae, wood anatomy is related to stem morphology in terms of the conferred support. In species of cacti with dimorphic wood, a unique process occurs in which the cambium stops producing wide-band tracheids (WBTs and produces fibers; this is associated with the aging of individuals and increases in size. Stem support and lignification have only been studied in fibrous tree-like species, and studies in species with WBTs or dimorphic wood are lacking. In this study, we approach this process with a chemical focus, emphasizing the role of wood lignification. We hypothesized that the degree of wood lignification in Cactaceae increases with height of the species and that its chemical composition varies with wood anatomy. To test this, we studied the chemical composition (cellulose, hemicellulose, and lignin content in 13 species (2 WBTs wood, 3 dimorphic, and 8 fibrous with contrasting growth forms. We also analyzed lignification in dimorphic and fibrous species to determine the chemical features of WBTs and fibers and their relationship with stem support. The lignin contents were characterized by Fourier transform infrared spectroscopy and high performance liquid chromatography. We found that 11 species have a higher percentage (>35% of lignin in their wood than other angiosperms or gymnosperms. The lignin chemical composition in fibrous species is similar to that of other dicots, but it is markedly heterogeneous in non-fibrous species where WBTs are abundant. The lignification in WBTs is associated with the resistance to high water pressure within cells rather than the contribution to mechanical support. Dimorphic wood species are usually richer in syringyl lignin, and tree-like species with lignified rays have more guaiacyl lignin. The results suggest that wood anatomy and lignin distribution play an important role in the chemical composition of wood, and further research is needed at the cellular level.

  15. Raman spectra of Martian glass analogues: A tool to approximate their chemical composition

    Science.gov (United States)

    Di Genova, Danilo; Kolzenburg, Stephan; Vona, Alessandro; Chevrel, Magdalena Oryaëlle; Hess, Kai-Uwe; Neuville, Daniel R.; Ertel-Ingrisch, Werner; Romano, Claudia; Dingwell, Donald B.

    2016-05-01

    Raman spectrometers will form a key component of the analytical suite of future planetary rovers intended to investigate geological processes on Mars. In order to expand the applicability of these spectrometers and use them as analytical tools for the investigation of silicate glasses, a database correlating Raman spectra to glass composition is crucial. Here we investigate the effect of the chemical composition of reduced silicate glasses on their Raman spectra. A range of compositions was generated in a diffusion experiment between two distinct, iron-rich end-members (a basalt and a peralkaline rhyolite), which are representative of the anticipated compositions of Martian rocks. Our results show that for silica-poor (depolymerized) compositions the band intensity increases dramatically in the regions between 550-780 cm-1 and 820-980 cm-1. On the other hand, Raman spectra regions between 250-550 cm-1 and 1000-1250 cm-1 are well developed in silica-rich (highly polymerized) systems. Further, spectral intensity increases at ~965 cm-1 related to the high iron content of these glasses (~7-17 wt % of FeOtot). Based on the acquired Raman spectra and an ideal mixing equation between the two end-members we present an empirical parameterization that enables the estimation of the chemical compositions of silicate glasses within this range. The model is validated using external samples for which chemical composition and Raman spectra were characterized independently. Applications of this model range from microanalysis of dry and hydrous silicate glasses (e.g., melt inclusions) to in situ field investigations and studies under extreme conditions such as extraterrestrial (i.e., Mars) and submarine volcanic environments.

  16. Chemical composition and physico-chemical properties of meat from capons as affected by breed and age

    Energy Technology Data Exchange (ETDEWEB)

    Diaz, O.; Rodriguez, L.; Torres, A.; Cobos, A.

    2010-07-01

    The influence of the breed [Mos (Spanish indigenous breed), Sasso T-44 and X-44 (commercial strains)] and the age (5, 6, 7 and 8 months) of capons (castrated male cockerels) on some qualitative traits of breast and drumstick meat were studied. The chemical composition (dry matter, protein, lipid and ash contents), pH, water holding capacity, drip loss, cooking loss, colour and texture (compression test and shear force) were measured. In breast meat, the Mos capon showed lower water holding capacity, higher drip loss and was lighter than the other breeds. In drumstick meat, the Mos capon showed lower lipid content, lower water holding capacity and was lighter and less red than the other breeds. Chemical composition, pH, water holding capacity, drip loss, colour and texture of the meat were significantly influenced by the age of the capons. The meat of the youngest animals showed higher ash content, higher pH, lower water holding capacity, higher drip loss, higher lightness and lower shear test values, than that of the older ones. In conclusion, the capon meat quality is influenced by breed and age of the capons. (Author) 36 refs.

  17. Evaluation of the performance of four chemical transport models in predicting the aerosol chemical composition in Europe in 2005

    Science.gov (United States)

    Prank, Marje; Sofiev, Mikhail; Tsyro, Svetlana; Hendriks, Carlijn; Semeena, Valiyaveetil; Vazhappilly Francis, Xavier; Butler, Tim; Denier van der Gon, Hugo; Friedrich, Rainer; Hendricks, Johannes; Kong, Xin; Lawrence, Mark; Righi, Mattia; Samaras, Zissis; Sausen, Robert; Kukkonen, Jaakko; Sokhi, Ranjeet

    2016-05-01

    Four regional chemistry transport models were applied to simulate the concentration and composition of particulate matter (PM) in Europe for 2005 with horizontal resolution ~ 20 km. The modelled concentrations were compared with the measurements of PM chemical composition by the European Monitoring and Evaluation Programme (EMEP) monitoring network. All models systematically underestimated PM10 and PM2.5 by 10-60 %, depending on the model and the season of the year, when the calculated dry PM mass was compared with the measurements. The average water content at laboratory conditions was estimated between 5 and 20 % for PM2.5 and between 10 and 25 % for PM10. For majority of the PM chemical components, the relative underestimation was smaller than it was for total PM, exceptions being the carbonaceous particles and mineral dust. Some species, such as sea salt and NO3-, were overpredicted by the models. There were notable differences between the models' predictions of the seasonal variations of PM, mainly attributable to different treatments or omission of some source categories and aerosol processes. Benzo(a)pyrene concentrations were overestimated by all the models over the whole year. The study stresses the importance of improving the models' skill in simulating mineral dust and carbonaceous compounds, necessity for high-quality emissions from wildland fires, as well as the need for an explicit consideration of aerosol water content in model-measurement comparison.

  18. Modification of Chemically Exfoliated Graphene to Produce Efficient Piezoresistive Polystyrene-Graphene Composites

    Science.gov (United States)

    Nasirpouri, Farzad; Pourmahmoudi, Hassan; Abbasi, Farhang; Littlejohn, Samuel; Chauhan, Ashok S.; Nogaret, Alain

    2015-10-01

    We report the chemical exfoliation of grapheneoxide from graphite and its subsequent reduction to graphene nanosheets (GN) to obtain highly conducting composites of graphene sheets in a polymer matrix. The effect of using graphite nanoparticles or flakes as precursors, and different drying methods, was investigated to obtain multilayer graphene sheets of atomically controlled thickness, which was essential to optimizing their dispersion in a polystyrene (PS) polymer matrix. In situ emulsion polymerization of the styrene monomer in the presence of GN was performed to obtain thin composite films with highly uniform dispersion and fewer graphene layers when GN were obtained from graphite flakes then freeze drying. The highest electrical conductivity of PS-GN composites was ~0.01 S/m for a graphene filling fraction of 2%. The piezoresistance of the PS-GN composites was evaluated and used in pressure sensor arrays with pressure field imaging capability.

  19. The chemical composition of red giants in 47 Tucanae I: Fundamental parameters and chemical abundance patterns

    CERN Document Server

    Thygesen, A O; Andrievsky, S; Korotin, S; Yong, D; Zaggia, S; Ludwig, H -G; Collet, R; Asplund, M; D'Antona, F; Meléndez, J; D'Ercole, A

    2014-01-01

    Context: The study of chemical abundance patterns in globular clusters is of key importance to constrain the different candidates for intra-cluster pollution of light elements. Aims: We aim at deriving accurate abundances for a large range of elements in the globular cluster 47 Tucanae (NGC 104) to add new constraints to the pollution scenarios for this particular cluster, expanding the range of previously derived element abundances. Methods: Using tailored 1D LTE atmospheric models together with a combination of equivalent width measurements, LTE, and NLTE synthesis we derive stellar parameters and element abundances from high-resolution, high signal-to-noise spectra of 13 red giant stars near the tip of the RGB. Results: We derive abundances of a total 27 elements (O, Na, Mg, Al, Si, Ca, Sc, Ti, V, Cr, Mn, Fe, Co, Ni, Cu, Zn, Y, Zr, Mo, Ru, Ba, La, Ce, Pr, Nd, Eu, Dy). Departures from LTE were taken into account for Na, Al and Ba. We find a mean [Fe/H] = $-0.78\\pm0.07$ and $[\\alpha/{\\rm Fe}]=0.34\\pm0.03$ in...

  20. Chemical, morphological and mechanical analysis of sisal fiber-reinforced recycled high-density polyethylene composites

    Directory of Open Access Journals (Sweden)

    2010-08-01

    Full Text Available Natural fibers are widely used as plastic composite material reinforcements. In this work, composites of postconsumer high-density polyethylene (HDPE reinforced with sisal fibers were prepared. PE and sisal fibers were chemically modified to improve their compatibilities, try to increase the hydrophobic character of the sisal fiber and hydrophilic character HDPE. Sisal was mercerized with a NaOH solution and acetylated and the PE was oxidized with KMnO4 solution. The chemically modified fibers were characterized by Fourier Transformed Infrared Spectroscopy (FTIR and 13C Nuclear Magnetic Resonance Spectroscopy (13C NMR. The composites were prepared by extrusion of modified and unmodified materials containing either 5 or 10 wt% fibers. The morphology of the obtained materials was evaluated by SEM. The fiber chemical modification improves it adhesion with matrix, but not benefit were obtained with HDPE oxidation. Flexural and impact tests demonstrated that the composites prepared with modified sisal fibers and unmodified PE present improved mechanical performance compared to pure PE.

  1. Enamels in stained glass windows: Preparation, chemical composition, microstructure and causes of deterioration

    International Nuclear Information System (INIS)

    Stained glass windows incorporating dark blue and purple enamel paint layers are in some cases subject to severe degradation while others from the same period survived the ravages of time. A series of dark blue, green-blue and purple enamel glass paints from the same region (Northwestern Europe) and from the same period (16-early 20th centuries) has been studied by means of a combination of microscopic X-ray fluorescence analysis, electron probe micro analysis and transmission electron microscopy with the aim of better understanding the causes of the degradation. The chemical composition of the enamels diverges from the average chemical composition of window glass. Some of the compositions appear to be unstable, for example those with a high concentration of K2O and a low content of CaO and PbO. In other cases, the deterioration of the paint layers was caused by the less than optimal vitrification of the enamel during the firing process. Recipes and chemical compositions indicate that glassmakers of the 16-17th century had full control over the color of the enamel glass paints they made. They mainly used three types of coloring agents, based on Co (dark blue), Mn (purple) and Cu (light-blue or green-blue) as coloring elements. Blue-purple enamel paints were obtained by mixing two different coloring agents. The coloring agent for red-purple enamel, introduced during the 19th century, was colloidal gold embedded in grains of lead glass.

  2. The main chemical composition of irradiated tuber of elevated gastrodia and Chinese Angelica

    International Nuclear Information System (INIS)

    This article studies the changes of the main chemicl composition of the Chinese drugs Gastradia Elata BL and Angelica Sinensis (Oliv) which were irradiated by 60Co γ-ray and stored for half an year. The content of the main chemical composition gastrodin of Gastradia Elata BL was measured by thin-layer chromatography and gas chromatography and the main chemical compsition Ligustilide of the essential oils of Chinese Angelica was also measured. The result shows that the contents of the main chemial composition gastrodin of irradiation groups and control groups are almost the same. The content of the main chemical compostion Ligustilide of the irradiated Chinese Angelica is close to the content of the control (not irradiated). There is no remarkable difference after the data were treated statistically (P > 0.05). The thin-layer chromatography colour-maculates were almost the same with the same Rf exponent. Irradiation of the tuber of elevated gastrodia and Chinese Angelica with 6 x 103 Gy of 60Co γ-rays and with subsequent storage of half an year will not change the effective composition of the drugs

  3. The use of chemical composition data in waste management planning - A case study

    International Nuclear Information System (INIS)

    As the waste industry continues to move from a disposal-based system to one based on a combination of recovery options, the need for information on the composition of waste increases and this is reflected by the amount of information on the physical composition of municipal solid wastes that is now available. However, there is far less information on the chemical composition of municipal solid waste. The results from a number of chemical surveys from Europe are compared and show a reasonable degree of agreement, but several problems were identified with the data. Chemical and physical compositional data are combined in a case study example to investigate the flow of key potential pollutants in an integrated solid waste management system that uses materials recycling, composting, incineration and landfilling. This case study has shown that an integrated waste management strategy diverts lead and cadmium away from composting and recycling to incineration, which effectively isolates these elements from the environment through efficient capture of the pollutants followed by secure landfilling or recycling of the residues. However, further work is needed to determine the distribution of mercury in incineration residues and its fate when the residues are landfilled

  4. Stability fields of smectites and illites as a function of temperature and chemical composition

    International Nuclear Information System (INIS)

    A thermodynamic ideal solid solution analogue is proposed which accounts the correlations which clearly reflect the temperatures at which the nonmineralic population are supposed to have been formed. The solid solution is considered, at a particle scale, as an ideal mixture of individual layers, weakly bent each to the next. Each layer presents the chemical composition of a given end member, so that the proportions of the different end members change from one particle to another. Considering one particle of a given chemical composition, the multipole solid solution theory allows to calculate the wheighted contributions of each end member into the ideal clay solid solution along with the chemical composition of the aqueous solutions in equilibrium with the considered particle in its independent microenvironment. This model is able to predict the nature of the chemical correlations which are expected, at a given temperature, within a given population. This model is also applied to the prediction of the temperature required for the conversion of smectite into illite during the burial diagenesis. (orig./HP)

  5. Magnesium hydroxide – expanded graphite composite pellets for a packed bed reactor chemical heat pump

    International Nuclear Information System (INIS)

    The chemical heat pump is a promising technology for the recovery of waste heat from industrial processes or cogeneration systems. It can be used for storing the surplus heat during low demand periods and release it for shaving the peaks of heat demand, with a benefit for the overall system efficiency. In this work, a packed bed reactor chemical heat pump based on the dehydration and hydration of magnesium hydroxide has been investigated. Due to its high thermal conductivity, expanded graphite was mixed with magnesium hydroxide to enhance heat transfer. The composite material, named EM, was developed and tested experimentally in order to understand the effects of expanded graphite on the chemical reactions occurring in the packed bed reactor. -- Highlights: • An expanded graphite/Mg(OH)2 composite was developed for a packed bed reactor chemical heat pump. • The expanded graphite/Mg(OH)2 composite (EM) was compressed in figure of pellets. • Higher reaction rates were observed for the dehydration and hydration of EM pellets. • EM pellets showed better performance in terms of heat storage and heat output. • EM pellets were able to withstand repetitive cyclic reactions without significant failures

  6. Physico-chemical properties of Brazilian cocoa butter and industrial blends. Part I Chemical composition, solid fat content and consistency

    Directory of Open Access Journals (Sweden)

    Ribeiro, A. P. B.

    2012-03-01

    Full Text Available A comparative study of the primary properties of six cocoa butter samples, representative of industrial blends and cocoa butter extracted from fruits cultivated in different geographical areas in Brazil is presented. The samples were evaluated according to fatty acid composition, triacylglycerol composition, regiospecific distribution, melting point, solid fat content and consistency. The results allowed for differentiating the samples according to their chemical compositions, thermal resistance properties, hardness characteristics, as well as technological adequacies and potential use in regions with tropical climates.

    En este trabajo se presenta un estudio comparativo de las propiedades primarias de mantecas de cacao, representativas de las mezclas industriales, y de la manteca de cacao original de diferentes zonas geográficas de Brasil. Las muestras fueron evaluadas de acuerdo a la composición de ácidos grasos, composición de triglicéridos, distribución de los ácidos grasos en las moléculas de triglicéridos, punto de fusión, contenido de grasa sólida y consistencia. Los resultados permitieron diferenciar las muestras por su composición química, propiedades de resistencia térmica, características de dureza, así como en materia de adecuaciones tecnológicas y los usos potenciales en las regiones de clima tropical.

  7. Relating particle hygroscopicity and CCN activity to chemical composition during the HCCT-2010 field campaign

    Directory of Open Access Journals (Sweden)

    Z. J. Wu

    2013-03-01

    Full Text Available Particle hygroscopic growth at RH =90%, cloud condensation nuclei (CCN activity, and size-resolved chemical composition were concurrently measured in the Thüringer Wald mid-level mountain range in central Germany in fall season of 2010. The median hygroscopicity parameter values, κ, of 50, 75, 100, 150, 200, and 250 nm particles derived from hygroscopicity measurements are respectively 0.14, 0.14, 0.17, 0.21, 0.24, and 0.28 during the sampling period. The closure between HTDMA-measured (κHTDMA and chemical composition-derived (κchem hygroscopicity parameters was performed based on the Zdanovskii–Stokes–Robinson (ZSR mixing rule. Using size-averaged chemical composition, the κ values are substantially overpredicted (30% and 40% for 150 and 100 nm particles. Introducing size-resolved chemical composition substantially improved closure, and the differences between κHTDMA and κchem are within 10%. We found that the evaporation of NH4NO3, which may happen in H-TDMA system, could lead to a discrepancy in predicted and measured particle hygroscopic growth. The hygroscopic parameter of the organic fraction, κorg is positively correlated with the O : C ratio (κorg =0.19 · (O : C−0.03. Such correlation is helpful to define the κorg value in the closure study. κ derived from CCN measurement was around 30% (varied with particle diameters higher than that determined from particle hygroscopic growth measurements (here, hydrophilic mode is considered only. This difference might be explained by the surface tension effects, solution non-ideality, and the partial solubility of constituents or non-dissolved particle matter. However, due to these effects being included in HTDMA-derived κ calculations, we could not distinguish the specific roles of these effects in creating this gap. Therefore, extrapolating from HTDMA data to properties at the point of activation should be done with great care. Finally, closure study between CCNc-measured (κ

  8. Changes in the chemical composition of the light crude by short-term weathering

    International Nuclear Information System (INIS)

    In the event of an oil spill, it is important to unambiguously identify the oil and link it to the known source in order to determine environmental impact and legal liability. The fate and behaviour of spilled oil depends on several physical, chemical and biological factors such as evaporation, dissolution, microbial degradation and photooxidation. The chemical composition of the spilled oil changes with weathering. The changes can have a significant effect on the oil's toxicity and can add to the difficulty of identifying spilled oil. This paper presents the results of changes in chemical composition of light crude oil by weathering under natural environmental conditions. Oil samples were analyzed on a gas chromatograph equipped with a mass selective detector. Light crude oil was obtained from the oil cabin of a tanker which spilled oil near the Dalian Sea near China in April 2005. It was shown that the saturated hydrocarbons of light crude oil distribute between n-C8 and n-C23. The most abundant n-alkanes are found in the n-C10 to n-C16. The main chemical compositions of the light crude oil are the n-alkanes and the isoprenoids. The aromatic compounds are subordinate chemical compositions of the light crude oil. A simulated weathering experiment showed that less than n-C12 of the n-alkanes, toluene, 1,3-dimethyl benzene is lost after 1 day of weathering. The n-C13, n-C14, naphthalene and 2-methyl-naphthalene are lost on the fifth day of weathering. N-C15 alkane composition indicates some weatherproof capability. The ratios of n-C17/pristine and n-C18/phytane were unchanged and useful in identifying the source of the light crude oil during the first 8-day weathering period. By the twenty-first day of weathering, the chemical composition underwent extreme alteration, and the source of the pollution could not be determined by the ratios of pristine/phytane. 12 refs., 3 tabs., 7 figs

  9. Surface chemical composition of human maxillary first premolar as assessed by X-ray photoelectron spectroscopy (XPS)

    Energy Technology Data Exchange (ETDEWEB)

    Lou, Leo [Orthodontic Graduate Program, Faculty of Medicine and Dentistry, University of Alberta (Canada); Nelson, Alan E. [Department of Chemical and Materials Engineering, University of Alberta (Canada)], E-mail: aenelson@dow.com; Heo, Giseon [Department of Statistics, Department of Dentistry, University of Alberta (Canada); Major, Paul W. [Orthodontic Graduate Program, Faculty of Medicine and Dentistry, University of Alberta (Canada)

    2008-08-30

    The surface chemical composition of dental enamel has been postulated as a contributing factor in the variation of bond strength of brackets bonded to teeth, and hence, the probability of bracket failure during orthodontic treatment. This study systematically investigated the chemical composition of 98 bonding surfaces of human maxillary premolars using X-ray photoelectron spectroscopy (XPS) to ascertain compositional differences between right and left first premolars. The major elements detected in all samples were calcium, phosphorus, oxygen, nitrogen and carbon. Surface compositions were highly variable between samples and several elements were found to be highly correlated. No statistical significant difference in the chemical composition of the maxillary right and left first premolars was found (p > 0.05). Knowledge of the chemical composition of enamel surfaces will facilitate future studies that relate this information to the variations in dental enamel bond strength.

  10. Surface chemical composition of human maxillary first premolar as assessed by X-ray photoelectron spectroscopy (XPS)

    Science.gov (United States)

    Lou, Leo; Nelson, Alan E.; Heo, Giseon; Major, Paul W.

    2008-08-01

    The surface chemical composition of dental enamel has been postulated as a contributing factor in the variation of bond strength of brackets bonded to teeth, and hence, the probability of bracket failure during orthodontic treatment. This study systematically investigated the chemical composition of 98 bonding surfaces of human maxillary premolars using X-ray photoelectron spectroscopy (XPS) to ascertain compositional differences between right and left first premolars. The major elements detected in all samples were calcium, phosphorus, oxygen, nitrogen and carbon. Surface compositions were highly variable between samples and several elements were found to be highly correlated. No statistical significant difference in the chemical composition of the maxillary right and left first premolars was found ( p > 0.05). Knowledge of the chemical composition of enamel surfaces will facilitate future studies that relate this information to the variations in dental enamel bond strength.

  11. Surface chemical composition of human maxillary first premolar as assessed by X-ray photoelectron spectroscopy (XPS)

    International Nuclear Information System (INIS)

    The surface chemical composition of dental enamel has been postulated as a contributing factor in the variation of bond strength of brackets bonded to teeth, and hence, the probability of bracket failure during orthodontic treatment. This study systematically investigated the chemical composition of 98 bonding surfaces of human maxillary premolars using X-ray photoelectron spectroscopy (XPS) to ascertain compositional differences between right and left first premolars. The major elements detected in all samples were calcium, phosphorus, oxygen, nitrogen and carbon. Surface compositions were highly variable between samples and several elements were found to be highly correlated. No statistical significant difference in the chemical composition of the maxillary right and left first premolars was found (p > 0.05). Knowledge of the chemical composition of enamel surfaces will facilitate future studies that relate this information to the variations in dental enamel bond strength

  12. Exploring the chemical sensitivity of a carbon nanotube/green tea composite.

    Science.gov (United States)

    Chen, Yanan; Lee, Yang Doo; Vedala, Harindra; Allen, Brett L; Star, Alexander

    2010-11-23

    Single-walled carbon nanotubes (SWNTs) possess unique electronic and physical properties, which make them very attractive for a wide range of applications. In particular, SWNTs and their composites have shown a great potential for chemical and biological sensing. Green tea, or more specifically its main antioxidant component, epigallocatechin gallate (EGCG), has been found to disperse SWNTs in water. However, the chemical sensitivity of this SWNT/green tea (SWNT/EGCG) composite remained unexplored. With EGCG present, this SWNT composite should have strong antioxidant properties and thus respond to reactive oxygen species (ROS). Here we report on fabrication and characterization of SWNT/EGCG thin films and the measurement of their relative conductance as a function of H(2)O(2) concentrations. We further investigated the sensing mechanism by Fourier transform infrared (FTIR) spectroscopy and field-effect transistor measurements (FET). We propose here that the response to H(2)O(2) arises from the oxidation of EGCG in the composite. These findings suggest that SWNT/green tea composite has a great potential for developing simple resistivity-based sensors. PMID:21043457

  13. The chemical composition of red giants in 47 Tucanae. I. Fundamental parameters and chemical abundance patterns

    Science.gov (United States)

    Thygesen, A. O.; Sbordone, L.; Andrievsky, S.; Korotin, S.; Yong, D.; Zaggia, S.; Ludwig, H.-G.; Collet, R.; Asplund, M.; Ventura, P.; D'Antona, F.; Meléndez, J.; D'Ercole, A.

    2014-12-01

    Context. The study of chemical abundance patterns in globular clusters is key importance to constraining the different candidates for intracluster pollution of light elements. Aims: We aim at deriving accurate abundances for a wide range of elements in the globular cluster 47 Tucanae (NGC 104) to add new constraints to the pollution scenarios for this particular cluster, expanding the range of previously derived element abundances. Methods: Using tailored 1D local thermodynamic equilibrium (LTE) atmospheric models, together with a combination of equivalent width measurements, LTE, and NLTE synthesis, we derive stellar parameters and element abundances from high-resolution, high signal-to-noise spectra of 13 red giant stars near the tip of the RGB. Results: We derive abundances of a total 27 elements (O, Na, Mg, Al, Si, Ca, Sc, Ti, V, Cr, Mn, Fe, Co, Ni, Cu, Zn, Y, Zr, Mo, Ru, Ba, La, Ce, Pr, Nd, Eu, Dy). Departures from LTE were taken into account for Na, Al, and Ba. We find a mean [Fe/H] = -0.78 ± 0.07 and [ α/ Fe ] = 0.34 ± 0.03 in good agreement with previous studies. The remaining elements show good agreement with the literature, but including NLTE for Al has a significant impact on the behavior of this key element. Conclusions: We confirm the presence of an Na-O anti-correlation in 47 Tucanae found by several other works. Our NLTE analysis of Al shifts the [Al/Fe] to lower values, indicating that this may be overestimated in earlier works. No evidence of an intrinsic variation is found in any of the remaining elements. Based on observations made with the ESO Very Large Telescope at Paranal Observatory, Chile (Programmes 084.B-0810 and 086.B-0237).Full Tables 2, 5, and 9 are only available at the CDS via anonymous ftp to http://cdsarc.u-strasbg.fr (ftp://130.79.128.5) or via http://cdsarc.u-strasbg.fr/viz-bin/qcat?J/A+A/572/A108Appendix A is available in electronic form at http://www.aanda.org

  14. Chemical Composition of PM2.5 at Rural Backround Site Košetice

    Czech Academy of Sciences Publication Activity Database

    Schwarz, Jaroslav; Havránek, Vladimír

    Praha : Česká aerosolová společnost, 2011 - (Vodička, P.), s. 37-38 ISBN 978-80-86186-31-3. [Výroční konference České aerosolové společnosti /12./. Čejkovice (CZ), 03.11.2011-04.11.2011] R&D Projects: GA ČR GAP209/11/1342; GA ČR GA205/09/2055 Institutional research plan: CEZ:AV0Z40720504; CEZ:AV0Z10480505 Keywords : PM2.5 * elemental composition * chemical composition Subject RIV: CF - Physical ; Theoretical Chemistry

  15. Processing–structure–property relations of chemically bonded phosphate ceramic composites

    Indian Academy of Sciences (India)

    H A Colorado; C Hiel; H T Hahn

    2011-07-01

    Mechanical properties and microstructures of a chemically bonded phosphate ceramic (CBPC) and its composite with 1.0 wt% graphite nanoplatelets (GNPs) reinforcement have been investigated. Microstructure was identified by using optical and scanning electron microscopes, X-ray tomography, and X-ray diffraction. In addition, weight loss of the resin at room temperature was studied. The microstructure characterization shows that CBPC is itself a composite with several crystalline (wollastonite and brushite) and amorphous phases. SEM and micro tomography show a homogeneous distribution of crystalline phases. Bending and compression strength of the CBPC was improved by reducing bubbles via preparation in vacuum.

  16. Thermo-chemical simulation of a composite offshore vertical axis wind turbine blade

    DEFF Research Database (Denmark)

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

    2012-01-01

    In the present study three dimensional steady state thermo-chemical simulation of a pultrusion process is investigated by using the finite element/nodal control volume (FE/NCV) technique. Pultrusion simulation of a composite having a C-shaped cross section is performed as a validation case. The...... obtained cure degree profiles for specific points match well with those in the literature. Following the validation case, the proposed numerical technique is applied to the modelling of the pultrusion of a composite blade which has a NACA0018 airfoil cross section. The effects of pulling speed and various...

  17. Influence of Cold Stress on the Chemical Composition of Carcass to Mangalica pigs

    OpenAIRE

    Monica Pârvu; Alexandru T. Bogdan; Ioana Cristina Andronie; Violeta Elena Simion; Adriana Amfim

    2012-01-01

    The purpose of the experiment was to evaluate the chemical composition of meat of Mangalica and Large Whitepigs. The animals were raised in alternative system and exposed to 8-11°C. The initial weight at was 100 kg.Preparation of the carcass was made after the classical method. Linear measures were made on warm carcass. Thechemical composition of meat was determined to Longissimus dorsi muscle. The protein content of meat wasdeterminate by Tecator - Kyltec Auto Analyze and fat content by Soxt...

  18. Chemical composition of whole body and carcass of Bos indicus and tropically adapted Bos taurus breeds.

    Science.gov (United States)

    Bonilha, S F M; Tedeschi, L O; Packer, I U; Razook, A G; Nardon, R F; Figueiredo, L A; Alleoni, G F

    2011-09-01

    Relationships between the chemical composition of the 9th- to 11th-rib section and the chemical composition of the carcass and empty body were evaluated for Bos indicus (108 Nellore and 36 Guzerah; GuS) and tropically adapted Bos taurus (56 Caracu; CaS) bulls, averaging 20 to 24 mo of age at slaughter. Nellore cattle were represented by 56 animals from the selected herd (NeS) and 52 animals from the control herd (NeC). The CaS and GuS bulls were from selected herds. Selected herds were based on 20 yr of selection for postweaning BW. Carcass composition was obtained after grinding, homogenizing, sampling, and analyzing soft tissue and bones. Similarly, empty body composition was obtained after grinding, homogenizing, sampling, analyzing, and combining blood, hide, head + feet, viscera, and carcass. Bulls were separated into 2 groups. Group 1 was composed of 36 NeS, 36 NeC, 36 CaS, and 36 GuS bulls and had water, ether extract (EE), protein, and ash chemically determined in the 9th- to 11th-rib section and in the carcass. Group 2 was composed of 20 NeS, 16 NeC, and 20 CaS bulls and water, EE, protein, and ash were determined in the 9th- to 11th-rib section, carcass, and empty body. Linear regressions were developed between the carcass and the 9th- to 11th-rib section compositions for group 1 and between carcass and empty body compositions for group 2. The 9th- to 11th-rib section percentages of water (RWt) and EE (RF) predicted the percentages of carcass water (CWt) and carcass fat (CF) with high precision: CWt, % = 29.0806 + 0.4873 × RWt, % (r(2) = 0.813, SE = 1.06) and CF, % = 10.4037 + 0.5179 × RF, % (r(2) = 0.863, SE = 1.26), respectively. Linear regressions between percentage of CWt and CF and empty body water (EBWt) and empty body fat (EBF) were also predicted with high precision: EBWt, % = -9.6821 + 1.1626 × CWt, % (r(2) = 0.878, SE = 1.43) and EBF, % = 0.3739 + 1.0386 × CF, % (r(2) = 0.982, SE = 0.65), respectively. Chemical composition of the 9th- to 11

  19. Chemical composition of volatile oils from leaves of Nectandra megapotamica Spreng. (Lauraceae)

    Energy Technology Data Exchange (ETDEWEB)

    Romoff, Paulete; Ferreira, Marcelo J.P., E-mail: romoff@mackenzie.b [Universidade Presbiteriana Mackenzie, Sao Paulo, SP (Brazil). Centro de Ciencias e Humanidades; Padilla, Ricardo; Toyama, Daniela O.; Favero, Oriana A. [Universidade Presbiteriana Mackenzie, Sao Paulo, SP (Brazil). Centro de Ciencias Biologicas e da Saude; Lago, Joao Henrique G. [Universidade Federal de Sao Paulo (UNIFESP), Diadema, SP (Brazil). Dept. de Ciencias Exatas e da Terra

    2010-07-01

    The volatile oils from Nectandra megapotamica Spreng. leaves, collected in February and August of 2007 and at 7:00 and 12:00 h (samples A - D), were extracted by hydrodistillation and the chemical composition was analyzed by GC-FID and GC/MS. A total of nineteen compounds were identified with predominance of oxygenated sesquiterpenes, among them, a-bisabolol, was the main constituent (62.3-69.4 %). After chromatographic separation procedures, this compound was purified from crude oil and its structure was confirmed by analysis of NMR data. This paper describes for the first time the composition of the leaves volatile oil from N. megapotamica. (author)

  20. Diffusion in plasma: the Hall effect, compositional waves, and chemical spots

    CERN Document Server

    Urpin, Vadim

    2016-01-01

    We consider diffusion caused by a combined influence of the electric current and the Hall effect, and argue that such diffusion can form inhomogeneities of the chemical composition in plasma. The considered mechanism can be responsible for a formation of element spots in laboratory and astrophysical plasmas. This current-driven diffusion can be accompanied by propagation of a particular type waves in which the impurity number density oscillate alone. These compositional waves exist if the magnetic pressure in plasma is much greater than the gas pressure,

  1. Effect of chemical composition and superheat on macrostructure of high Cr white iron castings

    Energy Technology Data Exchange (ETDEWEB)

    Dogan, Omer N.

    2005-08-01

    White cast irons are frequently used in applications requiring high wear resistance. High Cr white cast irons have a composite microstructure composed of hard (Fe,Cr)7C3 carbides in a steel matrix. Previous research has indicated that the equiaxed region of these high Cr white iron castings is much more wear resistant under high stress abrasive conditions than the columnar region, when the carbides are oriented perpendicular to the wear surface. In the present study, the effect of both the chemical composition, particularly carbon content, and the pouring superheat of the melt on the macrostructure of high Cr white iron castings is investigated.

  2. Investigation of the chemical composition-antibacterial activity relationship of essential oils by chemometric methods.

    Science.gov (United States)

    Miladinović, Dragoljub L; Ilić, Budimir S; Mihajilov-Krstev, Tatjana M; Nikolić, Nikola D; Miladinović, Ljiljana C; Cvetković, Olga G

    2012-05-01

    The antibacterial effects of Thymus vulgaris (Lamiaceae), Lavandula angustifolia (Lamiaceae), and Calamintha nepeta (Lamiaceae) Savi subsp. nepeta var. subisodonda (Borb.) Hayek essential oils on five different bacteria were estimated. Laboratory control strain and clinical isolates from different pathogenic media were researched by broth microdilution method, with an emphasis on a chemical composition-antibacterial activity relationship. The main constituents of thyme oil were thymol (59.95%) and p-cymene (18.34%). Linalool acetate (38.23%) and β-linalool (35.01%) were main compounds in lavender oil. C. nepeta essential oil was characterized by a high percentage of piperitone oxide (59.07%) and limonene (9.05%). Essential oils have been found to have antimicrobial activity against all tested microorganisms. Classification and comparison of essential oils on the basis of their chemical composition and antibacterial activity were made by utilization of appropriate chemometric methods. The chemical principal component analysis (PCA) and hierachical cluster analysis (HCA) separated essential oils into two groups and two sub-groups. Thyme essential oil forms separate chemical HCA group and exhibits highest antibacterial activity, similar to tetracycline. Essential oils of lavender and C. nepeta in the same chemical HCA group were classified in different groups, within antibacterial PCA and HCA analyses. Lavender oil exhibits higher antibacterial ability in comparison with C. nepeta essential oil, probably based on the concept of synergistic activity of essential oil components. PMID:22389175

  3. Features of water chemical composition of oligotrophic and eutrophic bogs in the South of the Tomsk region

    Science.gov (United States)

    Naymushina, O.

    2016-03-01

    On the basis of the actual material the analysis of chemical composition of bog waters in the territory of the South of the Tomsk region is carried out. The data on average concentration of macro and trace components, organic matter, pH of bog waters are obtained. Significant distinctions in a chemical composition of surface water for different types of bogs are revealed. The composition and macrostructure of humic acids by the example of eutrophic bogs is studied.

  4. Prediction of physical and chemical body compositions of purebred and crossbred Nellore cattle using the composition of a rib section.

    Science.gov (United States)

    Marcondes, M I; Tedeschi, L O; Valadares Filho, S C; Chizzotti, M L

    2012-04-01

    The goal of this research was to develop empirical equations to predict chemical and physical compositions of the carcass and the body using the composition of the 9th- to 11th-rib section (rib(9-11)) and other measurements. A database (n = 246) from 6 studies was developed and comprised 37 bulls (BU), 115 steers (STR), and 94 heifers (HF), of which 132 were Nellore (NEL), 76 were NEL × Angus crossbreds (NA), and 38 were NEL × Simmental crossbreds (NS). The right half carcass and the rib(9-11) from the left half carcass were analyzed for ether extract (EE), CP, and water. The remaining components were chemically analyzed to determine the composition of the body. A stepwise procedure was used to determine the variable inclusion in the regression models. The variables included were EE in the rib(9-11) (EER; %), CP in the rib(9-11) (CPR; %), water in the rib(9-11) (WR; %), visceral fat (VF; %; KPH and mesenteric fats), organs plus viscera (OV; %), carcass dressing percentage (CD; %), cold carcass weight (kg), and empty BW (EBW; kg). No sex or breed effects were found on EE and CP compositions of the carcass (C(EE) and C(CP), respectively; %); the equations were as follows: C(EE) = 4.31 + 0.31 × EER + 1.37 × VF [n = 241; R(2) = 0.83; mean square error (MSE) = 4.53] and C(CP) = 17.92 + 0.60 × CPR - 0.17 × CD (n = 238; R(2) = 0.50; MSE = 1.58). Breed affected water content in the carcass (C(W), %); the equations were as follows: C(W) = 48.74 + 0.28 × WR - 0.017 × EBW for NEL; C(W) = 46.69 + 0.32 × WR - 0.017 × EBW for NA; and C(W) = 38.06 + 0.48 × WR - 0.017 × EBW for NS (n = 243; R(2) = 0.67; MSE = 5.17). A sex effect was found on body chemical EE composition (BW(EE)); the equations were as follows: BW(EE) = 2.75 + 0.33 × EER + 1.80 × VF for BU; BW(EE) = 1.84 + 0.33 × EER + 1.91 × VF for STR; and BW(EE) = 4.77 + 0.33 × EER + 1.28 × VF for HF (n = 243; R(2) = 0.89; MSE = 3.88). No sex or breed effects were found on CP composition in the body (BW

  5. The chemical composition of carbon stars: The R-type stars

    OpenAIRE

    Zamora, Olga; Abia, Carlos; PLEZ, Bertrand; Dominguez, Inmaculada; Cristallo, Sergio

    2009-01-01

    The aim of this work is to shed some light on the problem of the formation of carbon stars of R-type from a detailed study of their chemical composition. We use high-resolution and high signal-to-noise optical spectra of 23 R-type stars selected from the Hipparcos catalogue. The chemical analysis is made using spectral synthesis in LTE and state-of-the-art carbon-rich spherical model atmospheres. We derive their CNO content (including the carbon isotopic ratio), average metallicity, lithium, ...

  6. Simulating the evolution of the chemical composition of the 1988/89 winter vortex

    Science.gov (United States)

    Jones, R. L.; Mckenna, D. S.; Poole, L. R.; Solomon, S.

    1990-01-01

    During the 1988/89 Airborne Arctic Stratospheric Expedition (AASE) observations of the chemical composition and aerosol characteristics of the winter vortex were obtained from a NASA ER-2 aircraft. In this paper we present interpretations of observations obtained on three ER-2 flights using a Lagrangian coupled photochemical-microphysical model. It is argued that observations obtained on Jaunary 16 and 19, and February 10, represent different stages of the chemical evolution of the vortex, from the early stages of chlorine release, the onset of denitrification and the intensively processed state.

  7. Effect of freeze-thaw cycling on the chemical composition of aqueous solutions of organic substances

    International Nuclear Information System (INIS)

    By means of spectrophotometry and chemical analysis, it was found that multiply repeated freezing-thawing cycles for aqueous solutions of carbohydrates, choline chloride, and diphenylpicrylhydrazyl (DPPH) alter the chemical composition of the final solutions. In most cases, one or two freeze-thaw cycles are shown to result in the same changes as those observed upon γ irradiation with absorbed doses of 200-300 Gy. The DPPH decay detected during the repetition of this treatment suggests that the degradation of organic molecules involves the stage of formation of free radicals. It was assumed that the cause of the observed processes is cavitation

  8. Chemical composition of essential oils and aromatic waters from different Italian Anthemis maritima populations.

    Science.gov (United States)

    Ciccarelli, Daniela; Noccioli, Cecilia; Pistelli, Luisa

    2013-09-01

    The chemical composition of the essential oils and aromatic waters isolated from six Italian Anthemis maritima populations was determined by GC-FID and GC/MS analyses. In total, 122 and 100 chemical compounds were identified in the essential oils and the aromatic waters, respectively. The main compound classes represented in the oils were monoterpene hydrocarbons, oxygenated monoterpenes, sesquiterpene hydrocarbons, oxygenated sesquiterpenes, and terpene esters. Multivariate chemometric techniques such as cluster analysis (CA) and principal coordinate analysis (PCO) were used to classify the samples according to the geographical origin. Statistical analysis allowed the attribution of the analyzed populations to different chemotype groups. PMID:24078600

  9. Effect of layering sequence and chemical treatment on the mechanical properties of woven kenaf–aramid hybrid laminated composites

    International Nuclear Information System (INIS)

    Highlights: • The mechanical properties of woven kenaf/Kevlar hybrid composites were analysed. • The layering sequences affect the mechanical properties of hybrid composites. • Treated kenaf improves the mechanical properties of hybrid composites. - Abstract: This work aims to evaluate the effect of layering sequence and chemical treatment on mechanical properties of woven kenaf–Kevlar composites. Woven kenaf–aramid hybrid laminated composites fabricated through hand lay-up techniques by arranging woven kenaf and Kevlar fabrics in different layering sequences and by using treated kenaf mat. To evaluate the effect of chemical treatment on hybrid composites, the woven kenaf mat was treated with 6% sodium hydroxide (NaOH) diluted solution and compared mechanical properties with untreated kenaf hybrid composites. Results shows that the tensile properties of hybrid composites improved in 3-layer composites compared to 4-layer composites. Hybrid composite with Kevlar as outer layers display a better mechanical properties as compared to other hybrid composites. Tensile and flexural properties of treated hybrid composites are better than non-treated hybrid composites. The fractured surface of hybrid composites was investigated by scanning electron microscopy. This study is a part of exploration of potential application of the hybrid composite in high velocity impact application

  10. Surge-Resistant Nanocomposite Enameled Wire Using Silica Nanoparticles with Binary Chemical Compositions on the Surface

    Directory of Open Access Journals (Sweden)

    Jeseung Yoo

    2015-01-01

    Full Text Available We developed polyesterimide (PEI nanocomposite enameled wires using surface-modified silica nanoparticles with binary chemical compositions on the surface. The modification was done using silanes assisted by ultrasound, which facilitated high density modification. Two different trimethoxysilanes were chosen for the modification on the basis of resemblance of chemical compositions on the silica surface to PEI varnish. The surface-modified silica was well dispersed in PEI varnish, which was confirmed by optical observation and viscosity measurement. The glass transition temperature of the silica-PEI nanocomposite increased with the silica content. The silica-dispersed PEI varnish was then used for enameled wire fabrication. The silica-PEI nanocomposite enameled wire exhibited a much longer lifetime compared to that of neat PEI enameled wire in partial discharge conditions.

  11. Chemical compositions of Four B-type Supergiants in the SMC Wing

    CERN Document Server

    Lee, J K; Dufton, P L; Ryan, R S I

    2004-01-01

    High-resolution UCLES/AAT spectra of four B-type supergiants in the SMC South East Wing have been analysed using non-LTE model atmosphere techniques to determine their atmospheric parameters and chemical compositions. The principle aim of this analysis was to determine whether the very low metal abundances ($-$1.1 dex compared with Galactic value) previously found in the Magellanic Inter Cloud region (ICR) were also present in SMC Wing. The chemical compositions of the four targets are similar to those found in other SMC objects and appear to be incompatible with those deduced previously for the ICR. Given the close proximity of the Wing to the ICR, this is difficult to understand and some possible explanations are briefly discussed.

  12. Impact of chabazite SSZ-13 textural properties and chemical composition on CO2 adsorption applications

    Energy Technology Data Exchange (ETDEWEB)

    Prodinger, Sebastian; Vemuri, Venkata Rama Ses; Varga, Tamas; McGrail, B. Peter; Motkuri, Radha K.; Derewinski, Miroslaw A.

    2016-04-01

    Chabazite SSZ-13 samples with varying silica content (Si/Al from 6 to 35) were synthesized in both stirring and static conditions to obtain material with changing particle size and morphology and thoroughly analysed with various characterization techniques. The role of particle size and chemical compositions of SSZ-13 chabazite on CO2 and N2 adsorption measurements was investigated. The Si/Al ratio played a major role for CO2 adsorption with Al-rich SSZ-13 showing a higher CO2 uptake than Al-poor material. This was attributed to the high density of active charged species in the chabazite cage. Particle size also played an important role in the sorption capacities with smaller particles, obtained in stirring conditions, showing enhanced CO2 uptakes compared to larger particles of same chemical composition. This was associated with an increased density of surface active sites and shorter diffusion pathways.

  13. Chemical composition and antibacterial activity of essential oil and extracts of Citharexylum spinosum flowers from Thailand.

    Science.gov (United States)

    Mar, Ae; Pripdeevech, Patcharee

    2014-05-01

    The chemical composition and antibacterial and antioxidant activities of the essential oil and various solvent extracts of Citharexylum spinosum flowers are reported. The chemical compositions were determined by GC-MS with 151 volatile constituents identified. Methyl benzoate, piperitone, maltol, and maple furanone were the major constituents. All extracts were tested for their antibacterial activity against eight microorganisms. The flower oil had the greatest antibacterial activity against all bacterial strains (MIC values of 31.2 microg/mL), while the other solvent extracts had MIC values ranging from 31.2 to 1000 microg/mL. The essential oil had the highest antioxidant activity and total phenol content with IC50 values of 62.7 and 107.3 microg/mL, respectively. PMID:25026728

  14. Effects of the manufacturing parameter and chemical composition on properties of HANA-4 cladding tube

    International Nuclear Information System (INIS)

    KEPCO NF conducted some researches to improve workability of HANA-4 cladding tube. It was changed to TREX outer diameter for increase Q-factor in first pilgering process related to the workability of cladding tube. In general, a increasing Q-factor leads to improvement yield of tubing manufacture in zirconium alloys. And decreasing of amount of alloying element changed cladding properties. The secondary phase particle analysis, the corrosion behavior and the texture were examined for HANA-4 alloys with adjustments of chemical compositions and TREX outer diameter for the purpose of enhancement formability. The precipitate type, size, and distribution of HANA-4 alloy were not changed as the chemical composition and the manufacturing parameters. The corrosion weight gain was decreased with reducing alloying elements, which considered the beneficial effect of reduced tin

  15. Chemical composition, digestibility and antinutritional factors content of two wild legumes: Styphonolobium burseroides and Acacia bilimekii.

    Science.gov (United States)

    Sotelo, A; Migliaro, P; Toledo, A; Contreras, J

    1999-01-01

    The chemical composition, digestibility and toxin contents of two wild legumes: Styphnolobium burseroides and Acacia bilimekii, collected in a semi-arid zone of Mexico, were determined. Both legumes had a high fiber content. The seeds of Styphnolobium burseroides had a low protein content (14%), and the pod a high content of reducing sugars. However the seeds of Acacia bilimekii had a high protein concentration (35%). The seed proteins were low in sulphur amino acids and tryptophan in both legumes but were rich in lysine. Trypsin inhibitors and lectins were present in low concentrations; alkaloids and cyanogenic glucosides were not detected. The in vitro digestibility for monogastric animals was low but the same test with ruminal juice showed a high digestibility for both legumes. Based on their chemical composition and digestibility, these legumes could be a good alternative source in the feeding of ruminants. PMID:10646630

  16. Evaluation of the Chemical Composition of Brazilian Commercial Cymbopogon citratus (D.C. Stapf Samples

    Directory of Open Access Journals (Sweden)

    Evandro de Castro Melo

    2008-08-01

    Full Text Available Abstract: The concentration and the chemical composition of the essential oils obtained from different samples of Cymbopogon citratus were evaluated. Among the 12 samples investigated (11 dried leaf samples and fresh plant leaves, seven presented essential oil concentrations within the threshold established by the Brazilian legislation. The moisture content was also determined and the majority of the samples presented humidity contents near 12%. The GC and GC/MS analyses of the essential oils led to identification of 22 compounds, with neral and geranial as the two major components. The total percentage of these two compounds varied within the investigated sample oils from 40.7% to 75.4%. In addition, a considerable variation in the chemical composition of the analyzed samples was observed. The process of grinding the leaves significantly decreased (by up to 68% the essential oil content, as well as the percentage of myrcene in the oils.

  17. Chemical composition and in vitro antioxidative potential of essential oil isolated from Curcuma longa L. leaves

    Institute of Scientific and Technical Information of China (English)

    R. Priya; A. Prathapan; K.G Raghu; A. Nirmala Menon

    2012-01-01

    Objective: To determine the chemical composition and antioxidant potential of essential oil isolated from the leaves of Curcuma longa (turmeric). Methods: Chemical composition of the oil was analyzed using GC-MS. Antiperoxidative potential was evaluated using linoliec acid emulsion system. Free radical scavenging activity was evaluated using stable DPPH and ABTS free radicals. Results: GC-MS analyses showed that major compound present in the turmeric leaf oil is b-sesquiphellandrene (22.8%) followed by terpinolene (9.5%). Essential oil also exhibited reductive potential and antioxidant potential in linoleic acid emulsion system along with DPPH and ABTS free radical scavenging potential. Conclusions: The overall result suggests that turmeric leaf oil is capable of retarding oxidation reaction and free radical mediated damage and can be developed as a potent natural antioxidant.

  18. 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)

  19. Chemical composition shape form and size of suspended solids in the atmosphere carried by rain water

    International Nuclear Information System (INIS)

    The interest of this work is to know about shape form, size and chemical composition of the suspended solids in the atmosphere of Toluca city and which are carried by the rains. The harvest of the samples was carried out during january to november 1999. The separation of the particulate matter from the rain water was realized through centrifugation. The solids were analysed by Scanning Electron Microscopy to know the shape form and size and the chemical composition was determined by X-ray dispersive energy in general form and of some particles individually analysed. The p H was measured to the solutions and the quantification of some dissolved ions by the Icp technique was realized. The results of the solids showed C, O, Na, Mg, Al, Si, S, P, K, Ca, Ti and Fe. Moreover they present sizes which varying from a ten of nanometers until some tens of microns. (Author)

  20. Chemical composition and antimicrobial activity of the essential oils of Pinus pinaster

    Directory of Open Access Journals (Sweden)

    Nouara Ait Mimoune

    2013-08-01

    Full Text Available Objective: To investigate the antimicrobial activity and chemical composition of essential oils of Pinus pinaster. Methods: Essential oils were extracted from the needles by hydrodistillation. The chemical composition of the obtained essential oils was analyzed using GC-MS technique. The antimicrobial potential has been tested against six microorganisms performing the disc diffusion assay. Results: Twenty-three components have been identified. β-caryophyllene (30.9% and β-selinene (13.45% were predominant compounds. The essential oil exhibited a moderate activity against Staphylococcus aureus, Bacillus subtilis and Escherichia coli, but did not affect the growth of Erwinia amylovora. Aspergillus flavus and Aspergillus niger were not inhibited by maritime pine essential oils. Conclusions: The essential oils from Pinus pinaster can be used as an antibacterial agent.

  1. Determination of Chemical Compositions on Adult Kidney Stones—A Spectroscopic Study

    Science.gov (United States)

    Raju, K.; Rakkappan, C.

    2008-11-01

    The chemical compositions of the kidney stones of both the sexes of patients, aged from 40 to 70, living in and around Chidambaram town are determined by using FT-IR and X-RD technique. The kidney stone samples used in the present study were procured from the Rajah Muthiah Medical College and Hospital, Annamalai University. The FT-IR spectra of different kidney stone samples were recorded in the range of 4000-400 cm-1. By identifying the characteristic frequency, the chemical compositions of the samples are determined. The results analyzed by FTIR technique were confirmed by X-RD method, in which the recorded X-ray diffractogram are compared with JCPDS files using search match method. Further analysis of XRD pattern also reveals the same.

  2. Assessment of Water and Sediment Physical-Chemical Composition in the West Coast of Maracaibo Lake

    OpenAIRE

    Jorge Moronta-Riera; Beatriz Riverón-Zaldívar

    2016-01-01

    The objective of this investigation was to determine the physical and chemical composition of the water streams and sediments of the Maracaibo Lake in three sampling areas located in Tía Juana, Lagunillas and Ceuta in order to know the level of contamination and assess water quality based on permissible values established by the 883 Decree. The results indicate that the overall hydrocarbon concentrations in the water and sediments are above permissible levels. It is concluded that petroleum p...

  3. Chemical Composition and Biological Activities of Fragrant Mexican Copal (Bursera spp.

    Directory of Open Access Journals (Sweden)

    Giulia Gigliarelli

    2015-12-01

    Full Text Available Copal is the Spanish word used to describe aromatic resins from several genera of plants. Mexican copal derives from several Bursera spp., Protium copal, some Pinus spp. (e.g., P. pseudostrobus and a few Fabaceae spp. It has been used for centuries as incense for religious ceremonies, as a food preservative, and as a treatment for several illnesses. The aim of this review is to analyze the chemical composition and biological activity of commercial Mexican Bursera copal.

  4. Chemical composition and antimicrobial activity of Hedyosmum brasiliense Miq., Chloranthaceae, essential oil

    OpenAIRE

    Karoline Kirchner; Alberto Wisniewski Jr; Alexandre Bella Cruz; Maique W. Biavatti; Netz, Daisy J. A.

    2010-01-01

    Hedyosmum brasiliense Miq., Chloranthaceae, is an endemic species of Brazil, locally known as "cidrão". Although H. brasiliense is popularly used as sedative, chemical constituents of this species remains uncharacterized. This work presents the essential oil composition, obtained by distillation of the fresh leaves and from a stored sample for three months, analysed by GC-FID and GC-MS. The inhibitory effects of essential oil were tested by the agar dilution method against six bacterial speci...

  5. Neem cake: chemical composition and larvicidal activity on Asian tiger mosquito.

    Science.gov (United States)

    Nicoletti, Marcello; Mariani, Susanna; Maccioni, Oliviero; Coccioletti, Tiziana; Murugan, Kardaray

    2012-07-01

    New pesticides based on natural products are urgently needed, in consideration of their environmental care and lower collateral effects. Neem oil, the main product obtained from Azadiractha indica A. Juss, commonly known as neem tree, is mainly used in medical devices, cosmetics and soaps, as well as important insecticide. Manufacturing of neem oil first includes the collection of the neem seeds as raw material used for the extraction. Neem cake is the waste by-product remaining after extraction processes. The quality of the oil, as that of the cake, strictly depends from the quality of seeds as well as from the type of extraction processes used, which strongly influences the chemical composition of the product. Currently, the different types of commercial neem cake on the market are roughly identified as oiled and deoiled cake, but several other differences can be detected. The differences are relevant and must be determined, to obtain the necessary correlation between chemical constitution and larvicidal activities. Six different batches of neem cake, marketed by several Indian and European companies, were analyzed by HPLC and HPTLC, and their fingerprints compared, obtaining information about the different compositions, focusing in particular on nortriterpenes, considered as the main active components of neem oil. Therefore, the chemical composition of each cake was connected with the biological activitiy, i.e., the effects of the extracts of the six neem cakes were tested on eggs and larvae of Aedes albopictus (Stegomyia albopicta) (Diptera: Culicidae), commonly known as Asian tiger mosquito. The results confirmed the previously reported larvicide effects of neem cake that, however, can now be related to the chemical composition, in particular with nortriterpenes, allowing in that way to discriminate between the quality of the various marketed products, as potential domestic insecticides. PMID:22422292

  6. Modelling chemical composition in electric systems ? implications to the dynamics of dye-sensitised solar cells

    OpenAIRE

    Kovanen, T.; Tarhasaari, T.; Kettunen, L.; Korppi-Tommola, J.

    2010-01-01

    Abstract Classical electromagnetism provides limited means to model electric generators. To extend the classical theory in this respect, additional information on microscopic processes is required. In semiconductor devices and electrochemical generators such information may be obtained by modelling chemical composition. Here we use this approach for the modelling of dye-sensitised solar cells. We simulate the steady-state current-voltage characteristics of such a cell, as well as i...

  7. Chemical composition and antifungal activity of essential oil of Chrysactinia mexicana gray.

    Science.gov (United States)

    Cárdenas-Ortega, Norma C; Zavala-Sánchez, Miguel A; Aguirre-Rivera, J Rogelio; Pérez-González, Cuauhtémoc; Pérez-Gutiérrez, Salud

    2005-06-01

    The chemical composition of the essential oil of Chysactinia mexicana was analyzed by gas chromatography-mass spectrometry. Seventeen compounds were characterized; eucalyptol (41.3%), piperitone (37.7%), and linalyl acetate (9.1%) were found as the major components. The essential oil of leaves and piperitone completely inhibited Aspergillus flavus growth at relatively low concentrations (1.25 and 0.6 mg/mL, respectively). PMID:15913293

  8. Chemical composition and metabolizable energy values of feedstuffs for broiler chickens

    OpenAIRE

    Eliane Aparecida da Silva; Luiz Fernando Teixeira Albino; Horacio Santiago Rostagno; Valdir Ribeiro Junior; Rodolfo Alves Vieira; Anastácia Maria de Araújo Campos; Rodrigo Knop Guazzi Messias

    2012-01-01

    The objective of this study was to estimate the values of apparent metabolizable energy and apparent metabolizable energy corrected for nitrogen balance and determine the chemical composition of the following feedstuffs: babassu meal, sunflower meal, corn gluten meal, babassu starch flour, meat and bones meal, beans, millet, cookies residue, pasta residue and bread-making residue. The traditional method of excreta collection was used with broilers in the period of 14 to 24 days of age, which ...

  9. Chemical Composition of Propolis from Different Regions in Java and their Cytotoxic Activity

    OpenAIRE

    Syamsudin; Sudjaswadi Wiryowidagdo; Partomuan Simanjuntak; Wan Lelly Heffen

    2009-01-01

    Problem statement: Propolis samples from tropical zones, such as Java (Indonesia) with its vast biodiversity, have become a subject of increasing scientific and economic attention. The association of the chemical composition of propolis from different geographic regions with cytotoxic activities lead to the identification of active principles, a fundamental tool to achieve standardization of this bee product. Approach: The purpose of this research was evaluate the quality of propolis collecte...

  10. Progress of Chemical Composition and Pharmacological Effects of Meretrix meretrix Linnaeus

    Institute of Scientific and Technical Information of China (English)

    Du; Zhengcai; Hou; Xiaotao; Huang; Qing; Deng; Jiagang; Fanshi; Fangcao

    2014-01-01

    Meretrix meretrix Linnaeus is a traditional marine drug. There are more than two thousand years of history using clamshell as a component of medicine.After a review of relevant literature at home and abroad for nearly 20 years,the author summarized chemical composition and pharmacological effects of M. meretrix,in order to provide a scientific basis for further development and utilization of M. meretrix.

  11. Metabolism and chemical composition of marine pelagic amphipods: synthesis toward a global bathymetric model

    OpenAIRE

    Ikeda, Tsutomu

    2013-01-01

    Respiration and ammonia excretion data and chemical composition data [water content, ash, carbon (C), nitrogen (N) and C:N ratios] of 18–32 amphipods (hyperiids and gammarids) from the epipelagic through bathypelagic zones of the world’s oceans were compiled. The independent variables including body mass, habitat temperature and mid-sampling depth were all significant predictors of respiration, accounting for 65–83 % of the variance in the data, while the former two variables were significant...

  12. The influence of chemical composition on structure and mechanical properties of austenitic Cr-Ni steels

    OpenAIRE

    A. Kurc-Lisiecka; M. Kciuk

    2013-01-01

    Purpose: The aim of the paper is to investigated the influence of the chemical composition on the structure and mechanical properties of austenitic Cr-Ni steels. Special attention was put on the effect of solution heat treatment on mechanical properties of examined steels. Design/methodology/approach: The examinations of static tensile tests were conducted on ZWICK 100N5A. Hardness measurements were made by Vickers method. The X-ray analyzes were realized with the use of Dron ...

  13. Evaluation of the Chemical Composition of Brazilian Commercial Cymbopogon citratus (D.C.) Stapf Samples

    OpenAIRE

    Evandro de Castro Melo; Róbson Ricardo Teixeira; Célia Regina ÃÂlvares Maltha; Ana Paula Martinazzo; Ulisses Alves Pereira; Luiz Cláudio Almeida Barbosa

    2008-01-01

    Abstract: The concentration and the chemical composition of the essential oils obtained from different samples of Cymbopogon citratus were evaluated. Among the 12 samples investigated (11 dried leaf samples and fresh plant leaves), seven presented essential oil concentrations within the threshold established by the Brazilian legislation. The moisture content was also determined and the majority of the samples presented humidity contents near 12%. The GC and GC/MS analyses of the essential oil...

  14. Chemical composition and antifungal activity of essential oil from Eucalyptus smithii against dermatophytes

    OpenAIRE

    Edilene Bolutari Baptista; Danielle Cristina Zimmermann-Franco; Alexandre Augusto Barros Lataliza; Nádia Rezende Barbosa Raposo

    2015-01-01

    ABSTRACT INTRODUCTION: In this study, we evaluated the chemical composition of a commercial sample of essential oil from Eucalyptus smithii R.T. Baker and its antifungal activity against Microsporum canis ATCC 32903, Microsporum gypseum ATCC 14683, Trichophyton mentagrophytes ATCC 9533, T. mentagrophytes ATCC 11480, T. mentagrophytes ATCC 11481, and Trichophyton rubrum CCT 5507. METHODS: Morphological changes in these fungi after treatment with the oil were determined by scanning electron ...

  15. Chemical composition, antioxidant activity and bioaccessibility studies in phenolic extracts of two Hericium wild edible species

    OpenAIRE

    Heleno, Sandrina A.;; Barros, Lillian; Martins, Anabela; Queiroz, Maria João R. P.; Morales, Patricia; Fernández-Ruiz, Virginia; Ferreira, Isabel C. F. R.

    2015-01-01

    Mushrooms are rich sources of bioactive compounds such as phenolic acids. When ingested, these molecules have to be released from the matrix to be transformed/absorbed by the organism, so that they can exert their bioactivity. Several in vitro methodologies have been developed in order to evaluate the bioavailability of bioactive compounds. Herein, two Hericium species were analyzed for their chemical composition and antioxidant activity. Furthermore, an in vitro digestion of the mushrooms an...

  16. Chemical composition, antioxidative and antimicrobial activity of essential oil Ocimum sanctum L.

    OpenAIRE

    Beatović Damir V.; Jelačić Slavica Ć.; Oparnica Čedo D.; Krstić-Milošević Dijana B.; Glamočlija Jasmina M.; Ristić Mihailo S.; Šiljegović Jovana D.

    2013-01-01

    Ocimum sanctum L. (Lamiaceae) sin. Ocimum tenuiflorum L. or Tulsi basil is a plant originating from tropical and subtropical areas of India. It is used in both the traditional and official medicine in India. Tulsi is a type of basil that is insufficiently explored and studied in Europe. The goal of this paper is to determine the chemical composition, antioxidative, and antimicrobial activity of the essential oil Ocimum sanctum L. grown in Serbia. The quantity of essential oil in 100 g o...

  17. Characterization of Anticancer, Antimicrobial, Antioxidant Properties and Chemical Compositions of Peperomia Pellucida Leaf Extract

    OpenAIRE

    Desy Fitrya Syamsumir; Julius Yong Fu Siong; Wendy Wee; Lee Seong Wei

    2011-01-01

    Peperomia pellucida leaf extract was characterized for its anticancer, antimicrobial, antioxidant activities, and chemical compositions. Anticancer activity of P. pellucida leaf extract was determined through Colorimetric MTT (tetrazolium) assay against human breast adenocarcinoma (MCF-7) cell line and the antimicrobial property of the plant extract was revealed by using two-fold broth micro-dilution method against 10 bacterial isolates. Antioxidant activity of the plant extract was then char...

  18. Chemical composition, antitumor and antimicrobial activity of Thymus vulgaris and T. algeriensis essential oils

    OpenAIRE

    Nikolic, Milos; Glamočlija, Jasmina; Ćirić, Ana; Ferreira, Isabel C.F.R.; Ricardo C. Calhelha; Perić, Tamara; Marković, Dejan; Giweli, Abdulhamed; Soković, Marina

    2013-01-01

    Plants from genus Thymus are often used in traditional medicine. Some of these species are important medicinal plants that are used in ethnomedicine. In this work, analysis of phytochemicals and bioactivity evaluation of Thymus vulgaris and T. algericnsis essential oils were done. The chemical composition of oils were evaluated using GC/MS; cytotoxic activity was tested against five human tumor cell lines MCF-7 (breast adenocarcinoma), NCI-H460 (non-small cell lung cancer), ...

  19. The puzzling chemical composition of GJ 436b's atmosphere: influence of tidal heating on the chemistry

    OpenAIRE

    Agúndez, Marcelino; Venot, Olivia; Selsis, Franck; Iro, Nicolas

    2014-01-01

    The dissipation of the tidal energy deposited on eccentric planets may induce a heating of the planet that affects its atmospheric thermal structure. Here we study the influence of tidal heating on the atmospheric composition of the eccentric (e = 0.16) "hot Neptune" GJ 436b, for which inconclusive chemical abundances are retrieved from multiwavelength photometric observations carried out during primary transit and secondary eclipse. We build up a one-dimensional model of GJ 436b's atmosphere...

  20. Chemical composition of Kiscellian silty sediment (sivica from the Trobni Dol area, Eastern Slovenia

    Directory of Open Access Journals (Sweden)

    Miha Mišič

    2003-06-01

    Full Text Available Kiscellian marine silt termed »sivica« is widely developed in Tertiary basins of Eastern Slovenia. Chemical composition is rather uniform and reflects the dominance of filosilicates (mainly illite/muscovite, chlorite and montmorillonite and carbonates. PAAS normalised REE and Y abundances are slightly depleted for La, Ce, Pr and Nd, very close to PAAS for Sm, Eu, Gd and Tb, and depleted for Y, Ho, Er, Tm, Yb and Lu.

  1. Cooling rate and chemical composition influence on structure of Al-Si-Cu alloys

    Directory of Open Access Journals (Sweden)

    M. Krupiński*, K. Labisz, Z. Rdzawski, M. Pawlyta

    2011-03-01

    Full Text Available Purpose: The aim of this work is to perform the investigation of cooling rate influence as well as rare earth metals modification on microstructure of the AC-AlSi7Cu3Mg and AC-AlSi12CuNiMg cast aluminium alloys. In the work also artificial neural networks were applied for investigations of the influence of the alloying additives on the properties of the AC-4XXX alloy.Design/methodology/approach: In the work the thermo – derivative analysis was applied for the reason to determine changes occurred in the Al-Si-Cu alloy caused by cooling rate change in a range between 0.1 and 1.4°C/s as well chemical composition of the investigated alloy. Also artificial neural networks were applied for prediction of the chemical composition and heat treatment parameters and influence on mechanical properties of the investigated aluminium alloys.Findings: The performed investigation are discussed for the reason of an possible improvement of thermal and structural properties of the alloy.Practical implications: The aim of the carried out investigations was to work out a computer aided tool for prediction of mechanical properties on the basis of registered parameters during the technological process as well as controlling the process in real time, which can be useful for foundry and cast industry for achieving of material with assumed properties.Originality/value: Chemical composition and cooling rate applied for the alloy influences the crystallisation process of the phases and eutectics, and that fore also the microstructure and determines at the same time the properties of these aluminium alloys. The achieved results can be used also for liquid metal processing in science and industry and obtaining of a required alloy microstructure and properties influenced by a proper production conditions. The determination of the technological process parameters as well chemical composition allows it to predict the material properties.

  2. Chemical Composition and Bioactivities of the Essential Oil from Etlingera yunnanensis against Two Stored Product Insects

    OpenAIRE

    Shan-Shan Guo; Chun-Xue You; Jun-Yu Liang; Wen-Juan Zhang; Zhu-Feng Geng; Cheng-Fang Wang; Shu-Shan Du; Ning Lei

    2015-01-01

    The chemical composition of the essential oil of Etlingera yunnanensis rhizomes and its contact and repellent activities against Tribolium castaneum (Herbst) and Liposcelis bostrychophila (Badonnel) were investigated. The essential oil obtained from E. yunnanensis rhizomes with hydrodistillation was performed by gas chromatography-flame ionization detection and gas chromatography-mass spectrometry. The main components of the essential oil were identified to be estragole (65.2%), β-caryophylle...

  3. CHEMICAL COMPOSITION, ANTIOXIDANT AND ANTIMICROBIAL PROPERTIES OF THREE ESSENTIAL OILS FROM PORTUGUESE FLORA

    OpenAIRE

    Martins, M. Rosário; Tinoco, M. Teresa; Almeida, A. S.; J. Cruz-Morais

    2012-01-01

    The present work reports on the evaluation of chemical composition and antioxidant and antimicrobial activities of essential oils of three aromatic herbs, growing wild in the south of Portugal, used in traditional food preparations: Foeniculum vulgare, Mentha spicata and Rosmarinus officinalis. The principal components of essential oils were anethole (41.2%) for F. vulgare, carvone (41.1%) for M. spicata and myrcene (23.7%) for R. officinalis. Essential oils showed antioxidant activity eit...

  4. Chemical composition and antibacterial activity of essential oils against human pathogenic bacteria

    OpenAIRE

    M. Sokovic; Marin, P.D.; Brkic, D.; Griensven, van, L.J.L.D.

    2008-01-01

    The chemical composition and antibacterial activity of essential oils from 10 aromatic plants Matricaria chamommilla, Mentha piperita, M. spicata, Lavandula angustifolia, Ocimum basilicum, Thymus vulgaris, Origanum vulgare, Salvia officinalis, Citrus limon and C. aurantium have been determined. Antibacterial activity of these oils and their components; i.e. linalyl acetate, linalool, limonene, pinene, ß-pinene, 1,8-cineole, camphor, carvacrol, thymol and menthol were assayed against a variety...

  5. Chemical Compositions, Antioxidant and Antimicrobial Activities of Essential Oils of Piper caninum Blume

    OpenAIRE

    Hasnah Mohd Sirat; Khong Heng Yen; Farediah Ahmad; Wan Mohd Nuzul Hakimi Wan Salleh

    2011-01-01

    Chemical composition, antioxidant and antimicrobial activities of the fresh leaves and stems oils of Piper caninum were investigated. A total of forty eight constituents were identified in the leaves (77.9%) and stems (87.0%) oil which were characterized by high proportions of phenylpropanoid, safrole with 17.1% for leaves and 25.5% for stems oil. Antioxidant activities were evaluated by using β-carotene/linoleic acid bleaching, DPPH radical scavenging and total phenolic content. Stems oil sh...

  6. Study of structure and chemical composition of soil humic substances isolated from humic podzol

    Czech Academy of Sciences Publication Activity Database

    Enev, V.; Klučáková, M.; Novák, František

    Brno : Masarykova univerzita, 2014, s. 23-27. ISBN 978-80-210-6842-1. [Pracovní setkání fyzikálních chemiků a elektrochemiků /14./. Brno (CZ), 03.06.2014-04.06.2014] Grant ostatní: GA MŠk(CZ) LO1211 Institutional support: RVO:60077344 Keywords : structure * chemical composition * soil humic substances * humic podzol Subject RIV: DF - Soil Science

  7. PM2,5 Chemical Composition at Rural Background Site in Central Europe

    Czech Academy of Sciences Publication Activity Database

    Schwarz, Jaroslav; Karban, Jindřich; Havránek, Vladimír; Chalupníčková, E.; Smolík, Jiří

    Twickenham, Middlesex: Mineralogical Society, 2011 - (Mitchell, R.; Williams, P.), s. 1829 ISSN 0026-461X. [Goldschmidt 2011. Praha (CZ), 14..08.2011-19.08.2011] R&D Projects: GA ČR GA205/09/2055 Institutional research plan: CEZ:AV0Z40720504; CEZ:AV0Z10480505 Keywords : PM2,5 * chemical composition * rural background Subject RIV: DI - Air Pollution ; Quality http://www.goldschmidt2011.org/

  8. Chemical composition and antiprotozoal activities of Colombian Lippia spp essential oils and their major components

    OpenAIRE

    Patricia Escobar; Sandra Milena Leal; Laura Viviana Herrera; Jairo Rene Martinez; Elena Stashenko

    2010-01-01

    The chemical composition and biological activities of 19 essential oils and seven of their major components were tested against free and intracellular forms of Leishmania chagasi and Trypanosoma cruzi parasites as well as Vero and THP-1 mammalian cell lines. The essential oils were obtained from different species of Lippia, a widely distributed genus of Colombian plants. They were extracted by microwave radiation-assisted hydro-distillation and characterised by GC-FID and GC-MS. The major com...

  9. Chemical composition of the essential oil from Microlicia graveolens growing wild in Minas Gerais

    OpenAIRE

    Anja B. Toudahl; Sidney A. V. Filho; Gustavo H. B. Souza; Luisa D. Morais; Orlando D. H. dos Santos; Anna K. Jäger

    2012-01-01

    The chemical composition of the essential oil of the aerial parts of Microlicia graveolens DC., Melastomataceae, growing wild in the mountains of Minas Gerais, Brazil, was investigated for the first time. A pale orange to colourless oil was obtained in a yield of 4.8%. The oil was analyzed by GC-MS. The main components were (+)-trans-pinocarvyl acetate (78.9%), (-)-trans-pinocarvyl acetate (5.5%) and β-pinene (3.8%).

  10. Chemical composition of the essential oil and fixed oil Bauhinia pentandra (Bong.) D. Dietr

    OpenAIRE

    Macia C. S. de Almeida; Souza, Luciana G. S.; Ferreira, Daniele A.; Francisco J. Q. Monte; Braz-Filho, Raimundo; Telma L. G. Lemos

    2015-01-01

    Background: Bauhinia pentandrais popularly known as “mororó” and inhabits the Caatinga and Savannah biomes. Objective: This paper reports the chemical composition of the essential and fatty oils of the leaves from B. pentandra. Materials and Methods: The essential oil was obtained by hydrodistillation and the fixed oil by extraction with hexane, followed by saponification with KOH/MeOH, and methylation using MeOH/HCl. The constituents were analyzed by gas chromatography-mass spectrometry. Res...

  11. The genetic code degeneracy and the amino acids chemical composition are connected

    OpenAIRE

    Negadi, Tidjani

    2009-01-01

    We show that our recently published Arithmetic Model of the genetic code based on Godel Encoding is robust against symmetry transformations, specially Rumer s one U > G, A > C, and constitutes a link between the degeneracy structure and the chemical composition of the 20 canonical amino acids. As a result, several remarkable atomic patterns involving hydrogen, carbon, nucleon and atom numbers are derived. This study has no obvious practical application(s) but could, we hope, add some new know...

  12. Phenotypical signs and chemical composition of Saccharomyces cerevisiae – mannoprotein producers

    Directory of Open Access Journals (Sweden)

    Agafia USATII

    2012-11-01

    Full Text Available Phenotypical signs and chemical composition of Saccharomyces cerevisiae CNMN-Y-18 and Saccharomyces cerevisiae CNMN-Y-19 yeast strains are described in this article. The presence of protein complexes with high content of irreplaceable amino acids and antioxidant enzymes, as well as polysaccharides with predominance of mannoproteins allow to recommend these yeast strains for the utilization in biotechnology. Results are of interest for the standard description of yeast strains offered as object for industrial appointment.

  13. Chemical composition of soils and biosolid by X-ray fluorescence technique

    International Nuclear Information System (INIS)

    The objective of the present work was to investigate the chemical composition of biosolid and soil treated with biosolid using the energy dispersive X-ray fluorescence. The elements Br, Co, Cr, Cu, Fe, Ga, Mn, Ni, Pb, Se, Sr, Ti and Zn were quantified and the results had been compared with Brazilian legislation. The Ni, Cu, Cr and Zn amounts were below the maximum values allowed. (author)

  14. Study of postharvest changes in the chemical composition of persimmon by HPLC

    OpenAIRE

    BALTACIOĞLU, Hande; Nevzat ARTIK

    2013-01-01

    Chemical composition, total phenolic content, phenolic compounds, sugars, and L-ascorbic acid content of persimmon fruits of 6 different persimmon cultivars obtained from Ordu, Turkey, were evaluated in this study. Four astringent persimmon cultivars (Türkay, Hachiya, 07 TH 13, and Moralı) and 2 nonastringent persimmon cultivars (Tozlayıcı and Fuyu) were used for analysis. In order to determine total phenolic content in persimmon fruits, the Folin-Ciocalteu colorimetric method was used. High-...

  15. Essential Oils from Ugandan Aromatic Medicinal Plants: Chemical Composition and Growth Inhibitory Effects on Oral Pathogens

    OpenAIRE

    Francis Ocheng; Freddie Bwanga; Moses Joloba; Abier Softrata; Muhammad Azeem; Katrin Pütsep; Anna-Karin Borg-Karlson; Celestino Obua; Anders Gustafsson

    2015-01-01

    The study assessed the growth inhibitory effects of essential oils extracted from ten Ugandan medicinal plants (Bidens pilosa, Helichrysum odoratissimum, Vernonia amygdalina, Hoslundia opposita, Ocimum gratissimum, Cymbopogon citratus, Cymbopogon nardus, Teclea nobilis, Zanthoxylum chalybeum, and Lantana trifolia) used traditionally in the management of oral diseases against oral pathogens. Chemical compositions of the oils were explored by GC-MS. Inhibitory effects of the oils were assessed ...

  16. Chemical Composition and Antibacterial Activity of Essential Oil of Cosmos bipinnatus Cav. Leaves from South Africa

    OpenAIRE

    Olajuyigbe, Olufunmiso; Ashafa, Anofi

    2014-01-01

    The chemical composition of essential oils isolated from the leaves of Cosmos bipinnatus and its antibacterial activity were analyzed by GC-MS and microbroth dilution assay respectively. The essential oil extracted from this plant was predominantly composed of monoterpenes (69.62%) and sesquiterpenes (22.73%). The antibacterial assay showed that the oil had significant inhibitory effects against both Gram-negative and Gram-positive bacteria isolates. The MIC of Gram-positive strains ranged be...

  17. Determination of antibacterial, antifungal activity and chemical composition of essential oil portion of unani formulation kulzam

    OpenAIRE

    K Ashok Kumar; Ram Kumar Choudhary; Bheemachari Joshi; V.Ramya; V Sahithi; Veena, P.

    2011-01-01

    Kulzam is a popular unani, liquid formulation; indicated for several minor ailments like cough, cold, running nose, sore throat, insect bites, earache, tooth ache, etc. by the manufacturer. However, this over the counter formulation has not been scientifically evaluated for its claimed uses. Hence in the present study an attempt has been to check the chemical composition, antibacterial and antifungal activity as most of the above-mentioned conditions are underpinned by microbial activity. The...

  18. Chemical composition analysis, antioxidant and antibacterial activity evaluation of essential oil of Atalantia monophylla Correa

    OpenAIRE

    Ramaraj Thirugnanasampandan; Ramya Gunasekar; Madhusudhanan Gogulramnath

    2015-01-01

    Background: Atalantia monophylla Correa. a small tree belongs to the family Rutaceae. It is distributed throughout India and in Tamil Nadu the species is commonly seen in foothills of dry vegetation. Objective: The aim was to hydrodistillate and analyze the chemical composition of essential oil from the fresh leaves of A. monophylla Correa. collected in two different seasons (December, 2013 and May, 2014) and to evaluate antioxidant and antibacterial activities of isolated essential oil. Mate...

  19. Antimicrobial properties and chemical composition of liquid and gaseous phases of essential oils

    OpenAIRE

    Křůmal, K. (Kamil); Kubátková, N. (Nela); Večeřa, Z. (Zbyněk); Mikuška, P. (Pavel)

    2015-01-01

    The antimicrobial properties of fifteen essential oils (EOs) tested on seventeen microorganisms were determined using the vapour–agar contact method. The most effective EOs (i.e. Lavandula angustifolia, Cymbopogon nardus, Citrus aurantifolia, Juniperus communis, Myrtus communis and Cinnamomum zeylanicum), whose volatile components afforded the best antimicrobial properties, were selected for a detailed study of chemical composition. All these six EOs contained one to three main component...

  20. Essential-oil composition and chemical variability of Senecio vulgaris L. from Corsica.

    Science.gov (United States)

    Andreani, Stéphane; Paolini, Julien; Costa, Jean; Muselli, Alain

    2015-05-01

    The chemical composition of the essential oils isolated from the aerial parts of Senecio vulgaris plants collected in 30 Corsican localities was characterized using GC-FID and GC/MS analyses. Altogether, 54 components, which accounted for 95.2% of the total oil composition, were identified in the 30 essential-oil samples. The main compounds were α-humulene (1; 57.3%), (E)-β-caryophyllene (2; 5.6%), terpinolene (3; 5.3%), ar-curcumene (4; 4.3%), and geranyl linalool (5; 3.4%). The chemical composition of the essential oils obtained from separate organs and during the complete vegetative cycle of the plants were also studied, to gain more knowledge about the plant ecology. The production of monoterpene hydrocarbons, especially terpinolene, seems to be implicated in the plant-flowering process and, indirectly, in the dispersal of this weed species. Comparison of the present results with the literature highlighted the originality of the Corsican S. vulgaris essential oils and indicated that α-humulene might be used as taxonomical marker for the future classification of the Senecio genus. A study of the chemical variability of the 30 S. vulgaris essential oils using statistical analysis allowed the discrimination of two main clusters according to the soil nature of the sample locations. These results confirmed that there is a relation between the soil nature, the chemical composition of the essential oils, and morphological plant characteristics. Moreover, they are of interest for commercial producers of essential oil in selecting the most appropriate plants. PMID:26010664

  1. Chemical composition and antimicrobial activity of peppermint (Mentha piperita L.) Essential oil

    OpenAIRE

    Mohaddese Mahboubi; Nastaran Kazempour

    2014-01-01

    Peppermint with antiseptic and known healing properties is a plant from the Labiatae family. In this study, we analyzed the chemical composition of essential oil from the flowering aerial part of peppermint by GC and GC/MS. Its antimicrobial activity was evaluated against bacteria, fungi and yeast by micro broth dilution assay. The fractional inhibitory concentration (FIC) and FIC Index (FICI) and related isobologram curve were determined by check board micro titer assay. The results...

  2. Chemical Composition, Antimicrobial and Antioxidant Activities of the Volatile Oil of Ganoderma pfeifferi Bres

    OpenAIRE

    Mohamed Al-Fatimi; Martina Wurster; Ulrike Lindequist

    2016-01-01

    In a first study of the volatile oil of the mushroom basidiomycete Ganoderma pfeifferi Bres., the chemical composition and antimicrobial and antioxidant activities of the oil were investigated. The volatile oil was obtained from the fresh fruiting bodies of Ganoderma pfeifferi Bres. By hydrodistillation extraction and analyzed by GC-MS. The antimicrobial activity of the oil was evaluated against five bacteria strains and two types of fungi strains, using disc diffusion and broth microdilution...

  3. Chemical Composition and Biological Activities of Fragrant Mexican Copal (Bursera spp.)

    OpenAIRE

    Giulia Gigliarelli; Becerra, Judith X.; Massimo Curini; Maria Carla Marcotullio

    2015-01-01

    Copal is the Spanish word used to describe aromatic resins from several genera of plants. Mexican copal derives from several Bursera spp., Protium copal, some Pinus spp. (e.g., P. pseudostrobus) and a few Fabaceae spp. It has been used for centuries as incense for religious ceremonies, as a food preservative, and as a treatment for several illnesses. The aim of this review is to analyze the chemical composition and biological activity of commercial Mexican Bursera copal.

  4. Physical and chemical composition and in situ degradability of macauba palm cake and leaves

    OpenAIRE

    Vanda Patrícia Barros Ferreira; Rosana Aparecida Possenti; Patrícia Brás; Ailton Marques Piza; Joaquim Adelino Azevedo Filho

    2013-01-01

    Macauba palm coconuts are rich in essential nutrients for animal feed formulation and after oil extraction, a large amount of residual biomass is produced, which must be used rationally to environmental preservation. This study aimed to determine the nutritional value of macauba palm (Acrocomia aculeata), cake and leaves, for its physical and chemical composition, dry matter (DM) in vitro digestibility (IVD) and in situ degradability. The test of in situ degradability was done using three rum...

  5. Comparison of different methods for extraction from Tetraclinis articulata: Yield, chemical composition and antioxidant activity

    OpenAIRE

    Herzi, Nejia; Bouajila, Jalloul; Camy, Séverine; Romdhane, Mehrez; Condoret, Jean-Stéphane

    2013-01-01

    International audience In the present study, three techniques of extraction: hydrodistillation (HD), solvent extraction (conventional 'Soxhlet' technique) and an innovative technique, i.e., the supercritical fluid extraction (SFE), were applied to ground Tetraclinis articulata leaves and compared for extraction duration, extraction yield, and chemical composition of the extracts as well as their antioxidant activities. The extracts were analyzed by GC-FID and GC-MS. The antioxidant activit...

  6. Chemical composition of lignin and lipids from tagasaste (Chamaecytisus proliferus spp. palmensis)

    OpenAIRE

    Marques, Gisela; Gutiérrez Suárez, Ana; Río Andrade, José Carlos del

    2008-01-01

    The chemical characterization of trimming residues of tagasaste (Chamaecytisus proliferus spp. palmensis), a hardy leguminous shrub that has been recently explored for pulp and paper production, was performed with especial emphasis in the composition of lignin and lipophilic extractives. Tagasaste was characterized by a high content of holocellulose (81%) and -cellulose (41%), while having a relatively low lignin content of 18.9%. The analysis of lignin was performed “in situ” by pyrolysis-g...

  7. Ultra high energy cosmic rays: implications of Auger data for source spectra and chemical composition

    OpenAIRE

    Aloisio, R.; Berezinsky, V.; P. Blasi(INAF Arcetri)

    2013-01-01

    We use a kinetic-equation approach to describe the propagation of ultra high energy cosmic ray protons and nuclei and calculate the expected spectra and mass composition at the Earth for different assumptions on the source injection spectra and chemical abundances. When compared with the spectrum, the elongation rate $X_{max}(E)$ and dispersion $\\sigma(X_{max})$ as observed with the Pierre Auger Observatory, several important consequences can be drawn: a) the injection spectra of nuclei must ...

  8. Concentration of mycotoxins and chemical composition of corn silage: a farm survey using infrared thermography.

    Science.gov (United States)

    Schmidt, P; Novinski, C O; Junges, D; Almeida, R; de Souza, C M

    2015-09-01

    This work evaluated the chemical composition and mycotoxin incidence in corn silage from 5 Brazilian dairy-producing regions: Castro, in central-eastern Paraná State (n=32); Toledo, in southwestern Paraná (n=20); southeastern Goiás (n=14); southern Minas Gerais (n=23); and western Santa Catarina (n=20). On each dairy farm, an infrared thermography camera was used to identify 3 sampling sites that exhibited the highest temperature, a moderate temperature, and the lowest temperature on the silo face, and 1 sample was collected from each site. The chemical composition and concentrations of mycotoxins were evaluated, including the levels of aflatoxins B1, B2, G1, and G2; zearalenone; ochratoxin A; deoxynivalenol; and fumonisins B1 and B2. The corn silage showed a highly variable chemical composition, containing, on average, 7.1±1.1%, 52.5±5.4%, and 65.2±3.6% crude protein, neutral detergent fiber, and total digestible nutrients, respectively. Mycotoxins were found in more than 91% of the samples, with zearalenone being the most prevalent (72.8%). All samples from the Castro region contained zearalenone at a high average concentration (334±374µg/kg), even in well-preserved silage. The incidence of aflatoxin B1 was low (0.92%). Silage temperature and the presence of mycotoxins were not correlated; similarly, differences were not observed in the concentration or incidence of mycotoxins across silage locations with different temperatures. Infrared thermography is an accurate tool for identifying heat sites, but temperature cannot be used to predict the chemical composition or the incidence of mycotoxins that have been analyzed, within the silage. The pre-harvest phase of the ensiling process is most likely the main source of mycotoxins in silage. PMID:26162792

  9. Chemical Composition and Antifungal Activity of Ocimum basilicum L. Essential Oil

    OpenAIRE

    Neveen Helmy Abou El-Soud; Mohamed Deabes; Lamia Abou El-Kassem; Mona Khalil

    2015-01-01

    BACKGROUND: The leaves of Ocimum basilicum L. (basil) are used in traditional cuisine as spices; its essential oil has found a wide application in perfumery, dental products as well as antifungal agents. AIM: To assess the chemical composition as well as the in vitro antifungal activity of O. basilicum L. essential oil against Aspergillus flavus fungal growth and aflatoxin B1 production. MATERIAL AND METHODS: The essential oil of O. basilicum was obtained by hydrodistillation and anal...

  10. An assessment of nutritional quality of hybryd maize grain based on chemical composition

    OpenAIRE

    Stevanović Milan; Mladenović-Drinić Snežana; Dragičević Vesna; Camdžija Zoran; Filipović Milomir; Veličković Nevena; Stanković Goran

    2012-01-01

    The aim of this study was to investigate chemical composition of grain of 20 maize hybrids, from different maturity groups, to define their nutritional quality from the point of main grain constituents: starch, total proteins, soluble proteins, oil, phytate, inorganic phosphorus, and soluble phenolics, as well as mass of 1.000 grains. A set of 20 ZP hybrids, FAO 400-800, were grown in a randomized complete block design (RCBD) at Zemun Polje (Serbia), during...

  11. Phylogenetic or environmental control on the organo-chemical composition of Sphagnum mosses?

    Science.gov (United States)

    Limpens, Juul; Nilsson, Mats

    2014-05-01

    Decomposition of organic material is one of the key processes that determines the size of the soil-feedback to global warming, but it is also a process surrounded with one of the largest uncertainties, making understanding its mechanistic drivers of crucial importance. In organic soils decomposition is closely determined by the organo-chemical composition of the litter entering the soil. But what, in turn drives the organo-chemical composition? Is it an emergent feature of the environment the species producing the litter grow in, or is it an evolutionary trait that can be tracked through the species' phylogeny? We set out to answer this question for one of the most import peat-forming plants on earth: the genus Sphagnum. We sampled 18 Sphagnum species, about equally distributed over 6 sites spanning a wide range of environmental conditions: most species were collected at multiple sites. For all species we characterised the chemical composition, focussing on three functional chemistry groups: (i) mineral elements, (ii) carbohydrate polymers (iii) non-carbohydrate polymers (aromatic and aliphatic compounds) . For each group of compounds we used multivariate statistical techniques to derive the degree of variation explained by environment: (site, position within site) and phylogeny (sections within genus Sphagnum). We found that the variation in mineral element concentrations was mostly explained by environment, with the biggest differences in the concentrations of basic cat-ions calcium and magnesium. In contrast, the variation in carbohydrates was mostly explained by phylogeny, with clear associations between sections and monosaccharides. The monosaccharide rhamnose was associated with species from the Acutifolia section known for their poor degradability, whereas xylose and galactose were closely associated with degradable species from the Cuspidata section. The composition non-carbohydrate polymers took an intermediate position: both environment and phylogeny

  12. EFFECT OF CHEMICAL TREATMENT ON RICE HUSK (RH REINFORCED POLYETHYLENE (PE COMPOSITES

    Directory of Open Access Journals (Sweden)

    Md. Rezaur Rahman

    2010-05-01

    Full Text Available In this study rice husk reinforced polyethylene composites and their test specimens were manufactured using a single screw extruder and an injection molding machine, respectively. Raw rice husk was chemically treated with benzene diazonium salt in alkali, acidic, and neutral media, in order to improve in the mechanical properties. The mechanical properties of the composites prepared from alkaline media treated rice husk were found to increase substantially compared to those of acidic media, neutral media, and untreated ones. However, the values for the alkaline media treated rice husk-PE composites at all mixing ratios were found to be higher than those of treated acidic media, treated neutral media, and untreated rice husk composites respectively. The SEM micrographs reveal that interfacial bonding between the treated filler and the matrix has significantly improved, suggesting that better dispersion of the filler into the matrix was achieved upon treatment of rice husk. Based on filler loading, 35% filler reinforced composites had the optimum set of mechanical properties among all composites manufactured.

  13. Relationship between the surface chemical composition of implants and contact with the substrate.

    Science.gov (United States)

    Lima da Costa Valente, Mariana; Shimano, Antonio Carlos; Marcantonio Junior, Elcio; Reis, Andréa Candido Dos

    2015-02-01

    The purpose of the study was to use scanning electron microscopy and energy dispersive x-ray spectrometry to assess possible morphologic and chemical changes after performing double-insertion and pullout tests of implants of different shapes and surface treatments. Four different types of implants were used-cylindrical machined-surface implants, cylindrical double-surface-treated porous implants, cylindrical surface-treated porous implants, and tapered surface-treated porous implants-representing a total of 32 screws. The implants were inserted into synthetic bone femurs, totaling 8 samples, before performing each insertion with standardized torque. After each pullout the implants were analyzed by scanning electron microscopy and energy dispersive x-ray spectrometry using a universal testing machine and magnified 35 times. No structural changes were detected on morphological surface characterization, only substrate accumulation. As for composition, there were concentration differences in the titanium, oxygen, and carbon elements. Implants with surface acid treatment undergo greater superficial changes in chemical composition than machined implants, that is, the greater the contact area of the implant with the substrate, the greater the oxide layer change. In addition, prior manipulation can alter the chemical composition of implants, typically to a greater degree in surface-treated implants. PMID:23339297

  14. Microstructures and Mechanical Properties of Laser Welding Joint of a CLAM Steel with Revised Chemical Compositions

    Science.gov (United States)

    Chen, Shuhai; Huang, Jihua; Lu, Qi; Zhao, Xingke

    2016-05-01

    To suppress the tendency to form delta ferrite in weld metal (WM) of China low activation martensitic (CLAM) steel joint, a CLAM steel with revised chemical compositions was designed. Laser welding of the CLAM steel was investigated. The microstructures of the WM and heat-affected zone were analyzed. The impact toughness of the WM was evaluated by a Charpy impact test method with three V notches. The influence of temper temperature on mechanical properties was analyzed. It was found that the delta ferrite was eliminated almost completely in laser WM of CLAM steel with revised chemical compositions which has lower tendency to form delta ferrite than original chemical compositions. The joint has higher tensile strength than the parent metal. With increasing the heat input, the impact toughness of the joint is approximatively equal with that of parent metal first and then decreases obviously. Temper treatment could effectively improve mechanical property of the joint. When the temper temperature exceeds 600 °C, the impact toughness of the joint is higher than that of the parent metal.

  15. Electrical performance and chemical composition studies on original and falsified Ni-MH batteries

    Directory of Open Access Journals (Sweden)

    Alexandre Urbano

    2010-12-01

    Full Text Available We show in this paper that falsifications on technological products have hit even rechargeable nickel metal hydride batteries (Ni-MH. The electrical performance and the electrode chemical composition were investigated for authentic and falsified AAA Ni-MH batteries, purchased in the Londrina market, Paraná State. Battery charge capacities were measured at 0,2 C discharge rate and average electrical power was measured at 0.2 and 0.8 C discharge rate. To perform chemical composition analysis, the batteries were vacuum dismantled and their electrodes were characterized by Energy Dispersive X-Ray Fluorescence (EDXRF and X-Ray Diffraction (XRD techniques. It was observed that the charge capacities for the authentic and falsified batteries were 920 and 154 mAh, respectively. The average electrical powers were 210 mW for authentic and 41 mW for falsified batteries. The cathode chemical composition was nickel hydroxide, (Ni(OH2, for both kinds of batteries. However, the anodes of these batteries were not composed by the same materials. The alloy LaNi5 was identified as the electroactive compound in the anode of the authentic battery, while cadmium hydroxide compound, (Cd (OH2, was identified in the falsified battery anode. The authentic battery therefore presented six times more charge capacity, five times more power at 0.2 C discharge rate and 6 times at 0.8 C than the falsified battery, and are yet less dangerous to environment due cadmium absence.

  16. Microstructures and Mechanical Properties of Laser Welding Joint of a CLAM Steel with Revised Chemical Compositions

    Science.gov (United States)

    Chen, Shuhai; Huang, Jihua; Lu, Qi; Zhao, Xingke

    2016-03-01

    To suppress the tendency to form delta ferrite in weld metal (WM) of China low activation martensitic (CLAM) steel joint, a CLAM steel with revised chemical compositions was designed. Laser welding of the CLAM steel was investigated. The microstructures of the WM and heat-affected zone were analyzed. The impact toughness of the WM was evaluated by a Charpy impact test method with three V notches. The influence of temper temperature on mechanical properties was analyzed. It was found that the delta ferrite was eliminated almost completely in laser WM of CLAM steel with revised chemical compositions which has lower tendency to form delta ferrite than original chemical compositions. The joint has higher tensile strength than the parent metal. With increasing the heat input, the impact toughness of the joint is approximatively equal with that of parent metal first and then decreases obviously. Temper treatment could effectively improve mechanical property of the joint. When the temper temperature exceeds 600 °C, the impact toughness of the joint is higher than that of the parent metal.

  17. Composition and Physico-Chemical Properties of Meat from Capons Fed Cereals

    Institute of Scientific and Technical Information of China (English)

    Olga Díaz; Luisana Rodríguez; Alexandr Torres; Ángel Cobos

    2013-01-01

    Chemical composition, physico-chemical properties and fatty acid composition of breast and drumstick meat from capons (castrated male cockerels) fed cereals were studied. Three groups of capons were reared. One group was fed ad libitum the same commercial diet until the 4th mon of life. The last month of its life, the capons of this group were fed corn. The second and third group of capons were fed the same diet from caponization. The second group was fed mixture of corn (50%) and wheat (50%). The third group of capons was fed 2/3 corn and 1/3 mixture of corn (50%) and barley (50%). Capons were reared under free-range conditions and slaughtered at 150 d of age. Caponization was performed at 48 d. No signiifcant effects of feeding in chemical composition, pH, water holding capacity, drip and cooking losses and texture of the meat were observed. The meat of the third group (capons fed 83%corn) was more yellow and showed higher content of C18:2 than that of the other capons.

  18. Microwave absorbing properties and enhanced infrared reflectance of Fe/Cu composites prepared by chemical plating

    International Nuclear Information System (INIS)

    Fe/Cu composite samples with Cu particles depositing on carbonyl iron sheets were prepared by chemical plating. Cu additions were uniformly distributed on the grain boundaries of the flaky carbonyl iron while keeping the internal structure of iron. Meanwhile, we found that the chemical plating time made a key point on both the microwave absorbing properties and infrared emissivity. With the growth of chemical plating time, the value of reflection loss gives a linear decrease and the infrared emissivity is reduced with a tendency of index reduction. When the plating time is less than 30 min, the reflection loss of the samples maintains above −20 GHz, moreover, prolonging the plating time more than 30 min, the infrared emissivity of the samples is reduced to 0.50 or less. It can be concluded that both the microwave absorbing and infrared properties are excellent at the optimal plating time of 30 min. - Highlights: • The Fe/Cu composites have been prepared by flake carbonyl iron as substrate. • The Fe/Cu composites exhibit enhanced Infrared characteristics. • The samples hold the most of the absorbing capacity and possess low infrared emissivity by controlling plating time

  19. GC-MS studies of the chemical composition of two inedible mushrooms of the genus Agaricus

    Directory of Open Access Journals (Sweden)

    Gjosheva Melania

    2007-12-01

    Full Text Available Abstract Background Mushrooms in the genus Agaricus have worldwide distribution and include the economically important species A. bisporus. Some Agaricus species are inedible, including A. placomyces and A. pseudopratensis, which are similar in appearance to certain edible species, yet are known to possess unpleasant odours and induce gastrointestinal problems if consumed. We have studied the chemical composition of these mushrooms using GC-MS. Results Our GC-MS studies on the volatile fractions and butanol extracts resulted in the identification of 44 and 34 compounds for A. placomyces and A. pseudopratensis, respectively, including fatty acids and their esters, amino acids, and sugar alcohols. The most abundant constituent in the volatiles and butanol were phenol and urea respectively. We also identified the presence of ergosterol and two Δ7-sterols. In addition, 5α,8α-Epidioxi-24(ξ-methylcholesta-6,22-diene-3β-ol was isolated for the first time from both mushrooms. Our study is therefore the first report on the chemical composition of these two species. Conclusion The results obtained contribute to the knowledge of the chemical composition of mushrooms belonging to the Agaricus genus, and provide some explanation for the reported mild toxicity of A. placomyces and A. pseudopratensis, a phenonomenon that can be explained by a high phenol content, similar to that found in other Xanthodermatei species.

  20. Chemical composition of the volatile oil from Zanthoxylum avicennae and antimicrobial activities and cytotoxicity

    Directory of Open Access Journals (Sweden)

    Yin Lin

    2014-01-01

    Full Text Available Background: Through literature retrieval, there has been no report on the research of the chemical components in Zanthoxylum avicennae (Lam. DC. This paper extracted and determined the chemical components of the volatile oil in Z. avicennae, and at the same time, measured and evaluated the bioactivity of the volatile oil in Z. avicennae. Materials and Methods: We extract the volatile oil in Z. avicennae by steam distillation method, determined the chemical composition of the volatile oil by GC-MS coupling technique, and adopt the peak area normalization method to measured the relative percentage of each chemical composition in the volatile oil. Meanwhile, we use the Lethal-to-prawn larva bioactivity experiment to screen the cytotoxicity activities of the volatile oil in Z. avicennae, and using the slanting test-tube experiment to determine and evaluate its antibacterial activities in vitro for the eight kinds of plant pathogenic fungi in the volatile oil of the Z. avicennae. Results: The results show that 68 kinds of compounds are determined from the volatile oil of Z. avicennae. The determined part takes up 97.89% of the total peak area. The main ingredients in the volatile oil of Z. avicennae are sesquiterpenoids and monoterpene. The test results show that the volatile oil in Z. avicennae has strong antibacterial activities and cytotoxicity, with the strongest antibacterial activity against the Rhizoctonia solani AG1-1A. Conclusion: This research results will provide reference data for understanding the chemical composition of the volatile oil in the aromatic plant of Z. avicennae and its bioactivity, and for its further development and application.

  1. Characterizing the origins of bottled water on the South Korean market using chemical and isotopic compositions

    International Nuclear Information System (INIS)

    We analyzed the major elements and stable isotopes of oxygen, hydrogen, and carbon (dissolved inorganic carbon: DIC) in various types of bottled water (domestic and foreign) commercially available in South Korea to classify the water types and to identify their origins. Only marine waters and some sparkling waters could be discriminated by their physicochemical compositions. Oxygen and hydrogen isotopes made marine waters more distinguishable from other water types. The determination of the carbon isotope composition of DIC was clearly useful for distinguishing between naturally and artificially sparkling waters. In addition, statistical analysis also appeared to aid in the discrimination of bottled water types. Our results indicate that a method that combines chemical and stable isotope composition analysis with statistical analysis is the most useful for discriminating water types and characterizing the origins of bottled water

  2. Influence of Stellar Flares on the Chemical Composition of Exoplanets and Spectra

    CERN Document Server

    Venot, Olivia; Carl, Shaun; Hashim, Aysha; Decin, Leen

    2016-01-01

    More than 3000 exoplanets have been detected so far, and more and more spectroscopic observations of exoplanets are performed. Future instruments are eagerly awaited as they will be able to provide spectroscopic data with a greater accuracy and sensitivity than what is currently available. An important aspect to consider is temporal stellar atmospheric disturbances that can influence the planetary composition, and hence spectra, and potentially can lead to incorrect assumptions about the steady-state atmospheric composition of the planet. We focus on perturbations that come from the host star in the form of flare events that significantly increase the photon flux impingement on the exoplanet atmosphere. In some cases, and particularly for M stars, this sudden increase may last for several hours. We aim at answering the question to what extent a stellar flare is able to modify the chemical composition of the planetary atmosphere and, therefore influence the resulting spectra. We use a 1D thermo-photochemical m...

  3. Thermal expansion of laminated, woven, continuous ceramic fiber/chemical-vapor-infiltrated silicon carbide matrix composites

    Science.gov (United States)

    Eckel, Andrew J.; Bradt, Richard C.

    1990-01-01

    Thermal expansions of three two-dimensional laminate, continuous fiber/chemical-vapor-infiltrated silicon carbide matrix composites reinforced with either FP-Alumina (alumina), Nextel (mullite), or Nicalon (Si-C-O-N) fibers are reported. Experimental thermal expansion coefficients parallel to a primary fiber orientation were comparable to values calculated by the conventional rule-of-mixtures formula, except for the alumina fiber composite. Hysteresis effects were also observed during repeated thermal cycling of that composite. Those features were attributed to reoccurring fiber/matrix separation related to the micromechanical stresses generated during temperature changes and caused by the large thermal expansion mismatch between the alumina fibers and the silicon carbide matrix.

  4. Chemical composition of the essential oil from Croton kimosorum, an endemic species to Madagascar.

    Science.gov (United States)

    Rabehaja, Delphin J R; Ihandriharison, Harilala; Ramanoelina, Panja A R; Benja, Rakotonirina; Ratsimamanga-Urverg, Suzanne; Bighelli, Ange; Casanova, Joseph; Tomi, Félix

    2014-01-01

    Croton kimosorum Leandri is an endemic species to Madagascar. The chemical composition of aerial parts, leaf and stem oils is reported for the first time. Analysis was carried out by combination of chromatographic (CC, GC), spectroscopic and spectrometric (MS, 13C NMR) techniques. In total, 76 compounds have been identified. Essential oil isolated from aerial parts contained mainly linalool (21.6%), sabinene (10.4%), 1,8-cineole (6.3%), beta-pinene (6.2%), (E)-beta-caryophyllene (5.9%), terpinen-4-ol (4.8%), geraniol (4,5%) and germacrene D (2.3%). In comparison with the first sample, the composition of leaf and stem oils varied slightly, while essential oil isolated by vapor distillation from a semi-industrial still exhibited similar composition. PMID:24660481

  5. Effects of reversible chemical reaction on Li diffusion and stresses in spherical composition-gradient electrodes

    International Nuclear Information System (INIS)

    Composition-gradient electrode materials have been proven to be one of the most promising materials in lithium-ion battery. To study the mechanism of mechanical degradation in spherical composition-gradient electrodes, the finite deformation theory and reversible chemical theory are adopted. In homogeneous electrodes, reversible electrochemical reaction may increase the magnitudes of stresses. However, reversible electrochemical reaction has different influences on stresses in composition-gradient electrodes, resulting from three main inhomogeneous factors—forward reaction rate, backward reaction rate, and reaction partial molar volume. The decreasing transition form of forward reaction rate, increasing transition form of backward reaction rate, and increasing transition form of reaction partial molar volume can reduce the magnitudes of stresses. As a result, capacity fading and mechanical degradation are reduced by taking advantage of the effects of inhomogeneous factors

  6. Facile Synthesis of Mono-Dispersed Polystyrene (PS/Ag Composite Microspheres via Modified Chemical Reduction

    Directory of Open Access Journals (Sweden)

    Wen Zhu

    2013-12-01

    Full Text Available A modified method based on in situ chemical reduction was developed to prepare mono-dispersed polystyrene/silver (PS/Ag composite microspheres. In this approach; mono-dispersed PS microspheres were synthesized through dispersion polymerization using poly-vinylpyrrolidone (PVP as a dispersant at first. Then, poly-dopamine (PDA was fabricated to functionally modify the surfaces of PS microspheres. With the addition of [Ag(NH32]+ to the PS dispersion, [Ag(NH32]+ complex ions were absorbed and reduced to silver nanoparticles on the surfaces of PS-PDA microspheres to form PS/Ag composite microspheres. PVP acted both as a solvent of the metallic precursor and as a reducing agent. PDA also acted both as a chemical protocol to immobilize the silver nanoparticles at the PS surface and as a reducing agent. Therefore, no additional reducing agents were needed. The resulting composite microspheres were characterized by TEM, field emission scanning electron microscopy (FESEM, energy-dispersive X-ray spectroscopy (EDS, XRD, UV-Vis and surface-enhanced Raman spectroscopy (SERS. The results showed that Ag nanoparticles (NPs were homogeneously immobilized onto the PS microspheres’ surface in the presence of PDA and PVP. PS/Ag composite microspheres were well formed with a uniform and compact shell layer and were adjustable in terms of their optical property.

  7. Chemical composition of herbaceous grass and legume species grown for maximum biomass production

    Energy Technology Data Exchange (ETDEWEB)

    Cherney, J.H.; Johnson, K.D.; Volenec, J.J.; Anliker, K.S.

    1988-01-01

    Chemical composition varies among herbaceous biomass species. As conversion processes are refined, it may be advantageous to select feedstocks based on compositional differences between or within species. Our objective was to characterize chemical composition in a range of herbaceous crops evaluated for biomass potential in the upper midwest region of the United States. Two legume and six grass species were evaluated under maximum economic yield management conditions. Although neutral detergent fiber (NDF) concentration ranged from 480 g kg/sup -1/ in the legumes to 740 g kg/sup -1/ in the grasses, year, site, harvest, or nitrogen (N) fertilization did not have a large effect on NDF. Lignin concentration was as low as 38 g kg/sup -1/ in the six grasses, and as high as 102 g kg/sup -1/ in the two legumes. Xylose concentration reflected differences in total hemicellulose for grasses and legumes, with a range of 55 g kg/sup -1/ in legumes to 200 g kg/sup -1/ in grasses. Concentrations of the alkali-labile phenolic monomer, p-coumaric acid, ranged from 0.2 g kg/sup -1/ in legumes to 11 g kg/sup -1/ in grasses. Species differences were more important than year, site, harvest, or N fertilization in determining composition of these herbaceous crops.

  8. Response of the global climate to changes in atmospheric chemical composition due to fossil fuel burning

    Science.gov (United States)

    Hameed, S.; Cess, R. D.; Hogan, J. S.

    1980-01-01

    Recent modeling of atmospheric chemical processes (Logan et al, 1978; Hameed et al, 1979) suggests that tropospheric ozone and methane might significantly increase in the future as the result of increasing anthropogenic emissions of CO, NO(x), and CH4 due to fossil fuel burning. Since O3 and CH4 are both greenhouse gases, increases in their concentrations could augment global warming due to larger future amounts of atmospheric CO2. To test the possible climatic impact of changes in tropospheric chemical composition, a zonal energy-balance climate model has been combined with a vertically averaged tropospheric chemical model. The latter model includes all relevant chemical reactions which affect species derived from H2O, O2, CH4, and NO(x). The climate model correspondingly incorporates changes in the infrared heating of the surface-troposphere system resulting from chemically induced changes in tropospheric ozone and methane. This coupled climate-chemical model indicates that global climate is sensitive to changes in emissions of CO, NO(x) and CH4, and that future increases in these emissions could augment global warming due to increasing atmospheric CO2.

  9. Gamma irradiation effect on the chemical composition and the antioxidant activity of Ipomoea batatas L.

    Science.gov (United States)

    Tahir, D.; Halide, H.; Wahab, A. W.; Kurniawan, D.

    2014-09-01

    The chemical composition and antioxidant activity of Ipomoea batatas L. (sweet potato) were studied by x-ray fluorescence (XRF) spectroscopy, Fourier transform infrared spectroscopy, and by the 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical scavenging capacity. The irradiation treatment was performed by using Cs-137 as a gamma sources in experimental equipment. Treatment by irradiation emerges as a possible conservation technique that has been tested successfully in several food products. The amount of chemical composition was changed and resulting new chemical for absorbed dose 40 mSv. Interestingly, it was found that gamma irradiation significantly increased the antioxidant activity, as measured by DPPH radical scavenging capacity. The antioxidant activity of Ipomoea batatas L. extract was dramatically increased in the non-irradiated sample to the sample irradiated at 40 mSv. These results indicate that gamma irradiation of Ipomoea batatas L. extract can enhance its antioxidant activity through the formation of a new chemical compound. Based on these results, increased antioxidant activity of Ipomoea batatas L. extracts by gamma rays can be applied to various industries, especially cosmetics, foodstuffs, and pharmaceuticals.

  10. Laboratory analogues simulating Titan's atmospheric aerosols: Compared chemical compositions of grains and thin films

    Science.gov (United States)

    Carrasco, Nathalie; Jomard, François; Vigneron, Jackie; Etcheberry, Arnaud; Cernogora, Guy

    2016-09-01

    Two sorts of solid organic samples can be produced in laboratory experiments simulating Titan's atmospheric reactivity: grains in the volume and thin films on the reactor walls. We expect that grains are more representative of Titan's atmospheric aerosols, but films are used to provide optical indices for radiative models of Titan's atmosphere. The aim of the present study is to address if these two sorts of analogues are chemically equivalent or not, when produced in the same N2-CH4 plasma discharge. The chemical compositions of both these materials are measured by using elemental analysis, XPS analysis and Secondary Ion Mass Spectrometry. The main parameter probed is the CH4/N2 ratio to explore various possible chemical regimes. We find that films are homogeneous but significantly less rich in nitrogen and hydrogen than grains produced in the same experimental conditions. This surprising difference in their chemical compositions could be explained by the efficient etching occurring on the films, which stay in the discharge during the whole plasma duration, whereas the grains are ejected after a few minutes. The higher nitrogen content in the grains possibly involves a higher optical absorption than the one measured on the films, with a possible impact on Titan's radiative models.

  11. Gamma irradiation effect on the chemical composition and the antioxidant activity of Ipomoea batatas L

    Energy Technology Data Exchange (ETDEWEB)

    Tahir, D., E-mail: dtahir@fmipa.unhas.ac.id; Halide, H., E-mail: dtahir@fmipa.unhas.ac.id; Kurniawan, D. [Department of Physics, Hasanuddin University, Makassar 90245 (Indonesia); Wahab, A. W. [Department of Chemistry, Hasanuddin University, Makassar 90245 (Indonesia)

    2014-09-25

    The chemical composition and antioxidant activity of Ipomoea batatas L. (sweet potato) were studied by x-ray fluorescence (XRF) spectroscopy, Fourier transform infrared spectroscopy, and by the 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical scavenging capacity. The irradiation treatment was performed by using Cs-137 as a gamma sources in experimental equipment. Treatment by irradiation emerges as a possible conservation technique that has been tested successfully in several food products. The amount of chemical composition was changed and resulting new chemical for absorbed dose 40 mSv. Interestingly, it was found that gamma irradiation significantly increased the antioxidant activity, as measured by DPPH radical scavenging capacity. The antioxidant activity of Ipomoea batatas L. extract was dramatically increased in the non-irradiated sample to the sample irradiated at 40 mSv. These results indicate that gamma irradiation of Ipomoea batatas L. extract can enhance its antioxidant activity through the formation of a new chemical compound. Based on these results, increased antioxidant activity of Ipomoea batatas L. extracts by gamma rays can be applied to various industries, especially cosmetics, foodstuffs, and pharmaceuticals.

  12. GC-MS investigation of the chemical composition of honeybee drone and queen larvae homogenate

    Directory of Open Access Journals (Sweden)

    Isidorov Valery A.

    2016-06-01

    Full Text Available Honeybee larva homogenate appears to be underrated and insufficiently explored but this homogenate is an exceptionally valuable honeybee product. Drone larva homogenate is very nutritional due to its high content of proteins, free amino acids, lipids, and carbohydrates. Moreover, the biological characteristics of honeybee larvae indicate the presence of chemical substances that may be pharmacologically active. In spite of the above, the chemical composition of honeybee larva has not gained as much attention as that of other bee products. In this study, the chemical composition of honeybee brood homogenate has been investigated using gas chromatography/mass spectrometry. As a result, it was possible to isolate as many as 115 extractive organic compounds from 6 samples of crude queen and 9 samples of drone homogenate. The main groups of substances extracted from either type of homogenate were composed of free amino acids and carbohydrates. The relative content of amino acids in queen homogenate as well as the share of essential amino acids were found to be higher than in the drone homogenate. Disaccharide trehalose was the dominant sugar in the queen larvae, whilst glucose prevailed in the drone larvae. Comparative chemical analyses of honeybee queen and drone larva homogenates have allowed us to make a preliminary inference about a higher overall value of the former.

  13. Gamma irradiation effect on the chemical composition and the antioxidant activity of Ipomoea batatas L

    International Nuclear Information System (INIS)

    The chemical composition and antioxidant activity of Ipomoea batatas L. (sweet potato) were studied by x-ray fluorescence (XRF) spectroscopy, Fourier transform infrared spectroscopy, and by the 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical scavenging capacity. The irradiation treatment was performed by using Cs-137 as a gamma sources in experimental equipment. Treatment by irradiation emerges as a possible conservation technique that has been tested successfully in several food products. The amount of chemical composition was changed and resulting new chemical for absorbed dose 40 mSv. Interestingly, it was found that gamma irradiation significantly increased the antioxidant activity, as measured by DPPH radical scavenging capacity. The antioxidant activity of Ipomoea batatas L. extract was dramatically increased in the non-irradiated sample to the sample irradiated at 40 mSv. These results indicate that gamma irradiation of Ipomoea batatas L. extract can enhance its antioxidant activity through the formation of a new chemical compound. Based on these results, increased antioxidant activity of Ipomoea batatas L. extracts by gamma rays can be applied to various industries, especially cosmetics, foodstuffs, and pharmaceuticals

  14. Estimation of aerosol water and chemical composition from AERONET at Cabauw, the Netherlands

    Directory of Open Access Journals (Sweden)

    A. J. van Beelen

    2013-06-01

    Full Text Available Remote sensing of aerosols provides important information on the atmospheric aerosol abundance. However, due to the hygroscopic nature of aerosol particles observed aerosol optical properties are influenced by atmospheric humidity, and the measurements do not unambiguously characterize the aerosol dry mass and composition which complicates the comparison with aerosol models. In this study we derive aerosol water and chemical composition by a modeling approach that combines individual measurements of remotely sensed aerosol properties (e.g. optical thickness, single scattering albedo, refractive index and size distribution from an AERONET (Aerosol Robotic Network sun-photometer with radiosonde measurements of relative humidity. The model simulates water uptake by aerosols based on the chemical composition and size distribution. A minimization method is used to calculate aerosol composition and concentration, which are then compared to in situ measurements from the Intensive Measurement Campaign At the Cabauw Tower (IMPACT, May 2008, the Netherlands. Computed concentrations show reasonable agreement with surface observations and follow the day-to-day variability in observations. Total dry mass (33 ± 12 μg m−3 and black carbon concentrations (0.7 ± 0.3 μg m−3 are generally accurately computed. The uncertainty in the AERONET (real refractive index (0.025–0.05 introduces larger uncertainty in the modeled aerosol composition (e.g. sulfates, ammonium nitrate or organic matter and leads to an uncertainty of 0.1–0.25 in aerosol water volume fraction. Water volume fraction is highly variable depending on composition, up to >0.5 at 70–80% and <0.1 at 40% relative humidity.

  15. Variation in chemical composition and acaricidal activity against Dermanyssus gallinae of four eucalyptus essential oils.

    Science.gov (United States)

    George, David R; Masic, Dino; Sparagano, Olivier A E; Guy, Jonathan H

    2009-06-01

    The results of this study suggest that certain eucalyptus essential oils may be of use as an alternative to synthetic acaricides in the management of the poultry red mite, Dermanyssus gallinae. At a level of 0.21 mg/cm(2), the essential oil from Eucalyptus citriodora achieved 85% mortality in D. gallinae over a 24 h exposure period in contact toxicity tests. A further two essential oils from different eucalyptus species, namely E. globulus and E. radiata, provided significantly (P eucalyptus essential oils regarding their chemical compositions. There appeared to be a trend whereby the essential oils that were composed of the fewer chemical components were the least lethal to D. gallinae. It may therefore be the case that the complexity of an essential oil's chemical make up plays an important role in dictating the toxicity of that oil to pests such as D. gallinae. PMID:19089590

  16. Influence of different parameters on the chemical composition of warm neptunes

    CERN Document Server

    Olivia, Venot; Franck, Selsis; Marcell, Tessenyi; Leen, Decin

    2014-01-01

    We developed a 1D photo-thermochemical model to study the atmosphere of warm exoplanets. The chemical scheme used in this model is completely new in planetology and has been constructed in collaboration with specialists of combustion. It has been validated as a whole through experiments on a large range of temperature (300 - 2500 K) and pressure (1 mbar - 100 bar), allowing to study a wide variety of exoplanets. We have used this chemical model to study the atmosphere of two warm Neptunes, GJ3470b and GJ436b, and the influence of different parameters (vertical mixing, metallicity, temperature, . . . ) on their chemical composition. We present here the results obtained in these studies.

  17. Chemical resistance, void content and tensile properties of oil palm/jute fibre reinforced polymer hybrid composites

    International Nuclear Information System (INIS)

    Tri layer hybrid composites of oil palm empty fruit bunches (EFB) and jute fibres was prepared by keeping oil palm EFB as skin material and jute as the core material and vice versa. The chemical resistance, void content and tensile properties of oil palm EFB/Jute composites was investigated with reference to the relative weight of oil palm EFB/Jute, i.e. 4:1, the fibre loading was optimized and different layering pattern were investigated. It is found from the chemical resistance test that all the composites are resistant to various chemicals. It was observed that marked reduction in void content of hybrid composites in different layering pattern. From the different layering pattern, the tensile properties were slightly higher for the composite having jute as skin and oil palm EFB as core material. Scanning electron microscopy (SEM) was used to study tensile fracture surfaces of different composites.

  18. Time-resolved fluorescence spectroscopic study of crude petroleum oils: influence of chemical composition.

    Science.gov (United States)

    Ryder, Alan G

    2004-05-01

    The fluorescence of crude petroleum oils is sensitive to changes in chemical composition and many different fluorescence methods have been used to characterize crude oils. The use of fluorescence lifetimes to quantitatively characterize oil composition has practical advantages over steady-state measurements, but there have been comparatively few studies in which the lifetime behavior is correlated with gross chemical compositional data. In this study, the fluorescence lifetimes for a series of 23 crude petroleum oils with American Petroleum Institute (API) gravities of between 10 and 50 were measured at several emission wavelengths (450-785 nm) using a 380 nm light emitting diode (LED) excitation source. It was found that the intensity average fluorescence lifetime (tau) at any emission wave-length does not correlate well with either API gravity or aromatic concentration. However, it was found that tau is strongly negatively correlated with both the polar and sulfur concentrations and positively correlated with the corrected alkane concentration. This indicates that the fluorescence behavior of crude petroleum oils is governed primarily by the concentration of quenching species. All the strong lifetime-concentration correlations are nonlinear and show a high degree of scatter, especially for medium to light oils with API gravities of between 25 and 40. The degree of scatter is greatest for oils where the concentrations (wt %) of the polar fraction is approximately 10 +/- 4%, the asphaltene component is approximately 1 +/- 0.5%, and sulfur is 0.5 +/- 0.4%. This large degree of scatter precludes the use of average fluorescence lifetime data obtained with 380 nm excitation for the accurate prediction of the common chemical compositional parameters of crude petroleum oils. PMID:15165340

  19. Inhable particulate matter from lime industries: Chemical composition and deposition in human respiratory tract

    Science.gov (United States)

    Godoi, Ricardo H. M.; Braga, Darci M.; Makarovska, Yaroslava; Alfoldy, Balint; Carvalho Filho, Marco A. S.; Van Grieken, Réne; Godoi, Ana Flavia L.

    Air pollution caused by the lime production industry has become a serious problem with potential effects to human health, especially in developing countries. Colombo is a city included in the Metropolitan Region of Curitiba (capital of Paraná State) in South Brazil. In Colombo city, a correlation has been shown between the lime production and the number of persons who need respiratory treatment in a local hospital, indicating that the lime industry can cause deleterious health effects in the exposed workers and population. This research was conducted to deal firstly with the characterization of the size distribution and chemical compositions of particles emitted from lime manufacturing and subsequently to assess the deposition rate of inhaled dolomitic lime aerosol particles in the human respiratory tract. The elemental chemical composition and particle size of individual atmospheric particles was quantitatively elucidated, including low-Z components like C, N and O, as well as higher-Z elements, using automated electron probe microanalysis. Information concerning the bulk composition is provided by energy-dispersive X-ray detection. The majority of the respirable particulate matter identified was composed of aluminosilicates, Ca-Mg oxides, carbon-rich particles, mixtures of organic particles and Ca-Mg carbonates, soot and biogenic particles. In view of the chemical composition and size distribution of the aerosol particles, local deposition efficiencies in the human respiratory system were calculated, revealing the deposition of CaO·MgO at extrathoracic, tracheobronchial and pulmonary levels. The results of this study offer evidence to the threat of the fine and coarse particles emitted from dolomite lime manufacturing, allowing policy-makers to better focus their mitigation strategies in an effective way, as well as to the dolomite producers for the purpose of designing and/or implementing improved emission controls.

  20. Quantifying the chemical composition of soil organic carbon with solid-state 13C NMR

    Science.gov (United States)

    Baldock, J. A.; Sanderman, J.

    2011-12-01

    The vulnerability of soil organic carbon (SOC) to biological decomposition and mineralisation to CO2 is defined at least partially by its chemical composition. Highly aromatic charcoal-like SOC components are more stable to biological decomposition than other forms of carbon including cellulose. Solid-state 13C NMR has gained wide acceptance as a method capable of defining SOC chemical composition and mathematical fitting processes have been developed to estimate biochemical composition. Obtaining accurate estimates depends on an ability to quantitatively detect all carbon present in a sample. Often little attention has been paid to defining the proportion of organic carbon present in a soil that is observable in solid-state 13C NMR analyses of soil samples. However, if such data is to be used to inform carbon cycling studies, it is critical that quantitative assessments of SOC observability be undertaken. For example, it is now well established that a significant discrimination exists against the detection of the low proton content polyaromatic structures typical of charcoal using cross polarisation 13C NMR analyses. Such discrimination does not exist where direct polarisation analyses are completed. In this study, the chemical composition of SOC as defined by cross polarisation and direct polarisation13C NMR analyses will be compared for Australian soils collected from under a diverse range of agricultural managements and climatic conditions. Results indicate that where significant charcoal C contents exist, it is highly under-represented in the acquired CP spectra. For some soils, a discrimination against alkyl carbon was also evident. The ability to derive correction factors to compensate for such discriminations will be assessed and presented.

  1. Photo-and radiation chemical properties of manganese (3) acetylacetonates and structurization of polymeric compositions

    International Nuclear Information System (INIS)

    Methods of electron, EPR- and IR-spectroscopy have been used to study photochemical and radiation chemical behaviour of manganese (3) acetylacetonates. Effect of manganese chelates on structurization of polymeric compositions (the first composition - on the basis of saponified copolymer of vinyl chloride with vinyl acetate and the second composition on the basis of cellulose derivatives) linked (1) or destructed (2) under γ-radiation is considered. Maximum degree of structurization for the composition 1 at the absence of the complex made up 64%, at the presence of Mn(AA)Λ3 - 88%, at the presence of Mn(AA)Λ2(OCOCFΛ3) - 94% (at equal radiation doses). Adding the complexes amplifies the process of structurization, Mn(AA)Λ2 (OCOCFΛ3) amplifying the process to a larger extent than Mn(AA)Λ3. The degree of destruction of the composition 2 at the presence of the complex is essentially lower than at its absence. The mechanism of chelate effect on polymers comprises the stage of associate formation: metal complex - free radical

  2. Chemical composition of Pleurotus pulmonarius (Fr. Quél., substrates and residue after cultivation

    Directory of Open Access Journals (Sweden)

    Silva Sueli Oliveira

    2002-01-01

    Full Text Available The cultivation of Pleurotus pulmonarius was carried out on different substrate: cotton waste (A leaves of Cymbopogon citratus (B and leaves of Panicum maximum Jacq. (C. The mushroom had a varied chemical composition; nevertheless they contained a good composition for to be used as a good source of protein for human kind. The results showed the higher protein content (29.19% and fibre (9.0% for the mushroom that were cultivated on cotton peel. The substrate composition and the residue composition after the mushroom harvest were: Protein for the substrate "A" (10.63% and 9.35%, "B" (7.87% and 4.24% and "C" (7.55% and 5.90 %; Lipids "A" (4.17% and 2.03%, "B"(2.77% and 3.20% and "C" (0.91% and 2.05%; Fibres "A" (49.02% and 37.02%, "B" (28.40% and 23.26% and "C" (37.50% and 26.66% respectively. The substrate "A" showed 0.048% of iron and "C" 0.14% of magnesium, 0.31% of potassium and 0.26% of calcium. In the substrate "B" the quantity of the minerals were very low in comparison to the other substrates. The residues after the harvest of mushroom could be used as fertiliser or as complement in the composition for animal feed.

  3. Effects of chemical fuel composition on energy generation from thermopower waves

    International Nuclear Information System (INIS)

    Thermopower waves, which occur during combustion within hybrid structures formed from nanomaterials and chemical fuels, result in a self-propagating thermal reaction and concomitantly generate electrical energy from the acceleration of charge carriers along the nanostructures. The hybrid structures for thermopower waves are composed of two primary components: the core thermoelectric material and the combustible fuel. So far, most studies have focused on investigating various nanomaterials for improving energy generation. Herein, we report that the composition of the chemical fuel used has a significant effect on the power generated by thermopower waves. Hybrid nanostructures consisting of mixtures of picric acid and picramide with sodium azide were synthesized and used to generate thermopower waves. A maximum voltage of ∼2 V and an average peak specific power as high as 15 kW kg−1 were obtained using the picric acid/sodium azide/multiwalled carbon nanotubes (MWCNTs) array composite. The average reaction velocity and the output voltage in the case of the picric acid/sodium azide were 25 cm s−1 and 157 mV, while they were 2 cm s−1 and 3 mV, in the case of the picramide/sodium azide. These marked differences are attributable to the chemical and structural differences of the mixtures. Mixing picric acid and sodium azide in deionized water resulted in the formation of 2,4,6-trinitro sodium phenoxide and hydrogen azide (H-N3), owing to the exchange of H+ and Na+ ions, as well as the formation of fiber-like structures, because of benzene π stacking. The negative enthalpy of formation of the new compounds and the fiber-like structures accelerate the reaction and increase the output voltage. Elucidating the effects of the composition of the chemical fuel used in the hybrid nanostructures will allow for the control of the combustion process and help optimize the energy generated from thermopower waves, furthering the development of thermopower waves as an energy

  4. Effects of chemical fuel composition on energy generation from thermopower waves

    Science.gov (United States)

    Yeo, Taehan; Hwang, Hayoung; Jeong, Dong-Cheol; Lee, Kang Yeol; Hong, Jongsup; Song, Changsik; Choi, Wonjoon

    2014-11-01

    Thermopower waves, which occur during combustion within hybrid structures formed from nanomaterials and chemical fuels, result in a self-propagating thermal reaction and concomitantly generate electrical energy from the acceleration of charge carriers along the nanostructures. The hybrid structures for thermopower waves are composed of two primary components: the core thermoelectric material and the combustible fuel. So far, most studies have focused on investigating various nanomaterials for improving energy generation. Herein, we report that the composition of the chemical fuel used has a significant effect on the power generated by thermopower waves. Hybrid nanostructures consisting of mixtures of picric acid and picramide with sodium azide were synthesized and used to generate thermopower waves. A maximum voltage of ˜2 V and an average peak specific power as high as 15 kW kg-1 were obtained using the picric acid/sodium azide/multiwalled carbon nanotubes (MWCNTs) array composite. The average reaction velocity and the output voltage in the case of the picric acid/sodium azide were 25 cm s-1 and 157 mV, while they were 2 cm s-1 and 3 mV, in the case of the picramide/sodium azide. These marked differences are attributable to the chemical and structural differences of the mixtures. Mixing picric acid and sodium azide in deionized water resulted in the formation of 2,4,6-trinitro sodium phenoxide and hydrogen azide (H-N3), owing to the exchange of H+ and Na+ ions, as well as the formation of fiber-like structures, because of benzene π stacking. The negative enthalpy of formation of the new compounds and the fiber-like structures accelerate the reaction and increase the output voltage. Elucidating the effects of the composition of the chemical fuel used in the hybrid nanostructures will allow for the control of the combustion process and help optimize the energy generated from thermopower waves, furthering the development of thermopower waves as an energy source.

  5. Chemical Mechanical Polishing of Glass Substrate with α-Alumina-g-Polystyrene Sulfonic Acid Composite Abrasive

    Institute of Scientific and Technical Information of China (English)

    LEI Hong; BU Naijing; ZHANG Zefang; CHEN Ruling

    2010-01-01

    Abrasive is the one of key influencing factors during chemical mechanical polishing(CMP) process. Currently, α-Alumina (α-Al2O3) particle, as a kind of abrasive, has been widely used in CMP slurries, but their high hardness and poor dispersion stability often lead to more surface defects. After being polished with composite particles, the surface defects of work pieces decrease obviously. So the composite particles as abrasives in slurry have been paid more attention. In order to reduce defect caused by pure α-Al2O3 abrasive, α-alumina-g-polystyrene sulfonic acid (α-Al2O3-g-PSS) composite abrasive was prepared by surface graft polymerization. The composition, structure and morphology of the product were characterized by Fourier transform infrared spectroscopy(FTIR), X-ray photoelectron spectroscopy(XPS), time-of-flight secondary ion mass spectroscopy(TOF-SIMS), and scanning electron microscopy(SEM), respectively. The results show that polystyrene sulfonic acid grafts onto α-Al2O3, and has well dispersibility. Then, the chemical mechanical polishing performances of the composite abrasive on glass substrate were investigated with a SPEEDFAM-16B-4M CMP machine. Atomic force microscopy(AFM) images indicate that the average roughness of the polished glass substrate surface can be decreased from 0.835 nm for pure α-Al2O3 abrasive to 0.583 nm for prepared α-Al2O3-g-PSS core-shell abrasive. The research provides a new and effect way to improve the surface qualities during CMP.

  6. Microbial Mineralization of Soil Organic Matter: Role of Chemical Composition and Structural Organization

    Science.gov (United States)

    Khalaf, M. M. R.; Chilom, G.; Rice, J. A.

    2014-12-01

    The purpose of this study is to quantitatively assess the effect of organic matter self-assembly on its resistance to microbial mineralization. Humic acids isolated from leonardite, two peats and a mineral soil were used as organic matter samples because they provide a broad range of variability in terms of the origin and nature of their organic components. Using a solvent-based fractionation method, humic acid samples were disassembled into a humic-like component and a humic-lipid composite. The humic-lipid composite was further disassembled into an amphiphilic and a lipid component using an alkaline aqueous solution. Mixtures that reproduced the composition of self-assembled samples were prepared by mixing the solid individual fractions in the exact proportions that they were present in the original material. The original humic acids or their corresponding mixtures were added as the sole carbon source in separate aerobic cultures containing a microbial consortium isolated from a mineral soil. After incubation for 125 days mineralization of the self-assembled samples was shown to be higher by as much as 70% compared to their corresponding physical mixtures. The extent of mineralization of the self-assembled samples was not correlated to the material's chemical composition or hydrophobicity index obtained from their 13C solid-state NMR spectra. In contrast, mineralization of the physical mixtures and the individual fractions did vary with chemical composition and was accompanied by preferential mineralization of alkyl carbon. These results suggest the microbial mineralization of humic acids is related to their self-assembly.

  7. Gummosis in grape hyacinth (Muscari armeniacum) bulbs: hormonal regulation and chemical composition of gums.

    Science.gov (United States)

    Miyamoto, Kensuke; Kotake, Toshihisa; Sasamoto, Makiko; Saniewski, Marian; Ueda, Junichi

    2010-05-01

    The purpose of this study was to investigate the hormonal regulation of gummosis in grape hyacinth (Muscari armeniacum) bulbs, focusing especially on the chemical composition of the gums. The application of ethephon (2-chloroethylphosphonic acid), an ethylene-releasing compound, at 1% and 2% (w/w) in lanolin as well as ethylene induced gummosis in the bulbs within several days. Methyl jasmonate (JA-Me, 0.1-2% in lanolin) alone had no effect on gummosis. However, simultaneous application of JA-Me and ethephon led to extreme stimulation of ethephon-induced gummosis. Ethephon-induced gummosis in the bulbs depended on the maturation stage of the bulbs, increasing from April to July, but decreasing from August to September. Regardless of the presence of JA-Me, the application of ethephon to the inflorescence axis of grape hyacinths did not induce gummosis. Gel permeation chromatography analysis revealed that gums were homogenous polysaccharides with an average molecular mass of ca. 8.3 kDa. Analysis of the sugar composition of the gums after hydrolysis revealed that the molar ratio of Rha:Ara:Gal:GalA:GlcA was 25:10:40:7:15. These results suggest that principal factors of gummosis as well as the chemical composition of gums differ between species of bulbous plants. PMID:19941030

  8. 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)

  9. Influence of genotype and feeding on chemical composition of organic chicken meat

    Directory of Open Access Journals (Sweden)

    Achille Franchini

    2010-01-01

    Full Text Available The aim of this study was to evaluate the effects of different genotypes and of feeding on meat chemical composition, including fatty acid profile, of chickens reared under organic conditions. Twomeat–typefast-growing(FG andmedium-growing(MG, andoneegg-typeslow-growing(SG wo meat–type fast-growing (FG and medium-growing (MG, and one egg-type slow-growing (SG strains were assigned to 2 different diets differing for the protein source: soybean (SB and faba bean (FB in partial substitution of soybean. Genotypemarkedlyaffectedthemeatchemical composition. Genotype markedly affected the meat chemical composition. SG breast and thigh meat showed lower content of lipids (P<0.01 than FG. Thehighestproportions he highest proportions of polyunsaturated fatty acids (PUFA n-6 and n-3 and the lowest proportion of monounsaturated (MUFA (P<0.01, as well as the lowest ratio of PUFA n6/n3 (P<0.01 were found in SG breast and thigh meat. MG showed always intermediate values. Asforfeeding, FBtreatmentproducedonlya As for feeding, FB treatment produced only a slight increment of protein in breast and a decrease of fat and ash in thigh meat. Total PUFA and PUFA n-6 resulted lower in both thigh and breast meat of FB groups compared to SB (P<0.01.

  10. The chemical composition and band gap of amorphous Si:C:N:H layers

    Science.gov (United States)

    Swatowska, Barbara; Kluska, Stanislawa; Jurzecka-Szymacha, Maria; Stapinski, Tomasz; Tkacz-Smiech, Katarzyna

    2016-05-01

    In this work we presented the correlation between the chemical composition of amorphous Si:C:N:H layers of various content of silicon, carbon and nitrogen, and their band gap. The series of amorphous Si:C:N:H layers were obtained by plasma assisted chemical vapour deposition method in which plasma was generated by RF (13.56 MHz, 300 W) and MW (2.45 GHz, 2 kW) onto monocrystalline silicon Si(001) and borosilicate glass. Structural studies were based on FTIR transmission spectrum registered within wavenumbers 400-4000 cm-1. The presence of Sisbnd C, Sisbnd N, Csbnd N, Cdbnd N, Cdbnd C, Ctbnd N, Sisbnd H and Csbnd H bonds was shown. The values band gap of the layers have been determined from spectrophotometric and ellipsometric measurements. The respective values are contained in the range between 1.64 eV - characteristic for typical semiconductor and 4.21 eV - for good dielectric, depending on the chemical composition and atomic structure of the layers.

  11. Liquefaction and Product Identification of Main Chemical Compositions of Wood in Phenol

    Institute of Scientific and Technical Information of China (English)

    Zhang Qiu-hui; Zhao Guang-jie; Jie Shu-jun

    2005-01-01

    To clarify liquefaction ratios and their construction variations of the main chemical compositions of wood in phenol using phosphoric acid as a catalyst, the chemical ingredients of wood such as holocellulose, cellulose and lignin, were measured and extracted according to GB methods. With Fourier transform infrared (FTIR), the product identification of reactant before and after liquefaction in phenol was investigated. The molecular weights and their distributions of the liquefaction results (acetone soluble parts) were studied by gel permeation chromatography (GPC). Results show that the molecular weights and their distributions of poplar and Chinese fir are almost the same. In poplar, the distribution of cellulose is the largest, and that of holocellulose the smallest after liquefaction. For Chinese fir, the distribution of holocellulose is the largest, and that of cellulose the smallest. After liquefaction of poplar cellulose, the change bands of FTIR spectrum observed below 1 600 cm-1, can be attributed to new substitute groups. The same is true for poplar lignin. For Chinese fir, the spectra of liquefaction results of all chemical compositions differ from that of wood meal. This reveals the more activity groups were produced because of the reactions between Chinese fir and phenol. The research shows that the liquefaction ratios of poplar decrease in the following order: holocellulose > lignin > cellulose, and those of Chinese fir in the order: lignin > cellulose > holocellulose.

  12. Chemical compatibility of SiC composite structures with fusion reactor helium coolant at high temperatures

    International Nuclear Information System (INIS)

    The thermodynamic stability of SiC/SiC composite structures proposed for fusion applications is presented in this paper. Minimization of the free energy for reacting species in the temperature range 773-1273 K is achieved by utilizing the NASA-Lewis Chemical Equilibrium Thermodynamics Code (CET). The chemical stability of the matrix (SiC), as well as several fiber coatings (BN and graphite) are studied. Helium coolant is assumed to contain O2 and water moisture impurities in the range 100-1000 ppm. The work is applied to recent Magnetic and Inertial Confinement Conceptual designs. The present study indicates that the upper useful temperature limit for SiC/SiC composites, from the standpoint of high-temperature corrosion, will be in the neighborhood of 1273 K. Up to this temperature, corrosion of SiC is shown to be negligible. The main mechanism of weight loss will be by evaporation to the plasma side. The presence of a protective SiO2 condensed phase is discussed, and is shown to result in further reduction of high-temperature corrosion. The thermodynamic stability of C and BN is shown to be very poor under typical fusion reaction conditions. Further development of chemically stable interface materials is required. (orig.)

  13. The Influence of Nanoadditives on the Biological Properties and Chemical Composition of Process Fluids

    Directory of Open Access Journals (Sweden)

    Borůvková K.

    2015-12-01

    Full Text Available In this study process fluids were tested after the addition of nanoparticles. Cooling and lubricating process fluids are used in machining to reduce wear on tools, to increase machine performance and to improve product quality. The use of process fluids leads to their pollution and contamination. Nanoparticles were added to the process fluids in order to increase their antibacterial activity. The selected nanoparticles were nanoparticles of metallic silver. The process fluids were modified by the addition of silver nitrate and ascorbic acid. Reduction of silver nanoparticles in the volume of the fluid was achieved using UV. The modified fluids were tested for their cytotoxicity and changes in chemical composition. The cytotoxicity of process fluids was tested for the purpose of verifying whether the process fluids, which are in direct contact with the skin of the operator, affect the health of the operator. The cytotoxicity of the process fluids was tested on human fibroblast cells. Fibroblasts are the basic cells of fibrous tissue. The cytotoxicity was tested by measuring the cell viability and using XTT. Analysis of chemical composition was performed for the purpose of determining the individual substances in the process fluids and their chemical stability. Qualitative analysis of the process fluids was performed using gas chromatography mass spectrometry (GC - MS.

  14. The Composition of the Sagittarius Dwarf Spheroidal Galaxy and Implications for Nucleosynthesis and Chemical Evolution

    CERN Document Server

    McWilliam, A; William, Andrew Mc; Smecker-Hane, Tammy A.

    2004-01-01

    We outline the results of a study of the chemical composition of 14 stars in the Sagittarius dwarf spheroidal galaxy (Sgr dSph). For the Sgr dSph stars with [Fe/H]>-1 the abundances are highly unusual, showing a striking enhancement in heavy s-process elements, increasing with [Fe/H], deficiencies of the alpha- elements (O, Si, Ca, and Ti), deficiencies of Al and Na, and deficiencies of the iron-peak elements Mn and Cu. Our abundances suggest that the composition of the metal-rich Sgr dSph stars is dominated by the ejecta of an old, metal-poor population, including products of AGB stars and type Ia supernovae (SN). We suggest two scenarios to explain the observations: Prolonged chemical evolution in a galaxy experiencing significant mass-loss, and chemical enrichment with episodic bursts of star formation. The Galactic globular cluster Omega Cen, and the Fornax dwarf galaxy show similar abundance patterns, which suggests that those systems evolved similar to the Sgr dSph.

  15. Effect of Gamma Rays and Salinity on Growth and Chemical Composition of Ambrosia maritima L. Plant

    International Nuclear Information System (INIS)

    This work achieved to study the effects of, mixture of salt 2:2:1 (Na Cl-CaCl2 and Mg SO4), concentration of (0, 2000, 4000 and 6000 ppm). on growth characters, some chemical components and some active ingredients in shoots of Ambrosia maritima plants, at different stages of growth, during two seasons. Pots 30 cm in diameter were filled of sand-loamy soils in appropriate concentration, all pots were irrigated with tap water. The exposed damsisa seeds to gamma rays, doses (0, 20, 40, and 80 Gy) before sowing together with control non irradiated seeds were sown in saline soils (0, 2000, 4000 and 6000 ppm). Soil salinity treatments caused a decrease in plant height, number of leaves, content of damsin, and an increase in fresh weigh, dry weight, total sugars, total chlorophyll, amino acids and ambrosine content. Also, Gamma rays caused an increase in most of growth parameters and most of chemical composition. It was observed that 40 or 80 Gy was more effective. We investigated the combined effect of levels of salinity and doses of radiation used, this interference improve growth parameters and chemical composition in ambrosia maritima plants and caused ascertain the role of gamma irradiation in plants tolerance to soil salinity and alleviation their harmful effect on plants.

  16. Organic and mineral fertilization and chemical composition of lemon balm (Melissa officinalis essential oil

    Directory of Open Access Journals (Sweden)

    Ana Carolina B. Sodré

    2012-02-01

    Full Text Available Melissa officinalis L., Lamiaceae, is an herb with great growth prospects in the cosmetic industry due to its essential oil. In order to improve its production, it is necessary to study related agricultural practices. This study evaluated the effect of organic and mineral fertilization on the chemical composition of lemon balm (Melissa officinalis L. essential oil. The assay was conducted at the "Fazenda Experimental do Glória" of the Federal University of Uberlândia, and essential oil extraction and GC/MS analyses were completed by the Centre for Research and Development on Plant Genetic Resources of the Campinas Agronomic Institute. The assay was conducted in a randomized complete block design with three replications. The tested treatments were six types of fertilization (0, 1, 2, 4, 8 kg.m-2 of cattle manure and mineral fertilizing with 60 g.m-2 of NPK 4-14-8 + 4 g.m-2 of boric acid with four replications. The essential oil was extracted by hydrodistillation in a modified Clevenger apparatus. The chemical composition was analyzed by GC/MS. The essential oil presented the same compounds for all treatments; however, the relative proportion of some chemical constituents was altered according to the treatment. Neral, geranial, and citronellal were the major constituents.

  17. Chemical composition and biological activity of essential oils of Dracocephalum heterophyllum and Hyssopus officinalis from Western Himalaya

    Science.gov (United States)

    The essential oils of two representatives of the Lamiaceae-family, Dracocephalum heterophyllum Benth. and Hyssopus officinalis L., are described for their antifungal, antibacterial and larvicidal as well as biting deterrent activities. Additionally, the essential oils’ chemical compositions, analyze...

  18. The Relationship between Chemical Compositions, Meat Quality, and Palatability of the 10 Primal Cuts from Hanwoo Steer

    Science.gov (United States)

    Jung, Eun-Young; Hwang, Young-Hwa

    2016-01-01

    The relationship between chemical compositions, meat quality traits, and palatability attributes in 10 primal cuts from Hanwoo steer carcasses were assessed. Sensory palatability attributes of Hanwoo beef were more closely related with fat content than to moisture or protein content. Among the chemical compositions, only fat had a significant correlation with juiciness (0.67, ptenderness (0.32, p0.05). Overall palatability was negatively correlated with drip loss (−0.32, ptenderness, flavor, and juiciness. PMID:27194921

  19. The effect of elevated CO2 on the chemical composition and construction costs of leaves of 27 C3 species

    OpenAIRE

    POORTER, H.; Berkel, Y. van; Baxter, B; Hertog, J. den; Dijkstra, P.; Gifford, R.M.; K. L. Griffin; Roumet, C.; Roy, J; Wong, S. C.

    1997-01-01

    We determined the proximate chemical composition as well as the construction costs of leaves of 27 species, grown at ambient and at a twice-ambient partial pressure of atmospheric CO₂. These species comprised wild and agricultural herbaceous plants as well as tree seedlings. Both average responses across species and the range in response were considered. Expressed on a total dry weight basis, the main change in chemical composition due to CO₂ was the accumulation of total non-structural carbo...

  20. Chemical Composition and In Vitro Antibacterial Activity of Mentha spicata Essential Oil against Common Food-Borne Pathogenic Bacteria

    OpenAIRE

    Yasser Shahbazi

    2015-01-01

    The aim of the present study was to investigate chemical composition and antibacterial activity of essential oil from the leaf of Mentha spicata plant against common food-borne pathogenic bacteria (Staphylococcus aureus, Bacillus subtilis, Bacillus cereus, Listeria monocytogenes, Salmonella typhimurium, and Escherichia coli O157:H7). Chemical composition of the essential oil was identified by gas chromatography coupled with mass spectrometer detector (GC-MS). The antibacterial activity of the...

  1. Chemical Composition and Antimicrobial Activity of Leaf, Ripe and Unripe Peel of Bitter Orange (Citrus aurantium) Essential Oils

    OpenAIRE

    Fatemeh Azhdarzadeh; Mohammad Hojjati

    2016-01-01

    Background and Objectives: The chemical composition and antimicrobial activity of bitter orange (Citrus aurantium) leaf, ripe and unripe peel essential oils, cultivated in southwest of Iran, were investigated. Materials and Methods: The analysis of chemical composition of hydro-distilled essential oils was carried out by GC-MS. The disc diffusion and broth micro-dilution were used to assay the antimicrobial effect of achieved essential oils. Results: According to the GC-MS analysis, 3...

  2. Chemical Composition of Artemisia annua L. Leaves and Antioxidant Potential of Extracts as a Function of Extraction Solvents

    OpenAIRE

    Iqbal, Shahid; Younas, Umer; Chan, Kim Wei; Zia-Ul-Haq, Muhammad; Ismail, Maznah

    2012-01-01

    This study was conducted to investigate the chemical and nutritional composition of Artemisia annua leaves in addition to determination of antioxidant potential of their extracts prepared in different solvents. Chemical composition was determined by quantifying fat, protein, carbohydrate, fiber, tocopherol, phytate, and tannin contents. Extraction of A. annua leaves, for antioxidant potential evaluation, was carried out using five solvents of different polarities, i.e., hexane, chloroform, et...

  3. Evaluation of various feedstuffs of ruminants in terms of chemical composition and metabolisable energy content

    Directory of Open Access Journals (Sweden)

    Dinesh Kumar

    2015-05-01

    Full Text Available Aim: The aim was to determine the chemical composition and metabolisable energy (ME content of feedstuffs used in ruminant animals using in vitro method. Materials and Methods: A total of 18 feedstuffs used for ruminant feeding including cultivated non-leguminous fodders like maize, sorghum, pearl millet, and oat; leguminous fodders like cowpea and berseem; agro-industrial by-products such as wheat bran, deoiled rice bran, rice polish, wheat straw, and concentrates such as mustard oil cake, groundnut cake, soybean meal, cotton seed cake, grains like maize, oat, wheat, and barley were taken for this study. Chemical compositions and cell wall constituents of test feeds were determined in triplicate. The crude protein (CP content was calculated as nitrogen (N × 6.25. True dry matter digestibility (TDMD, true organic matter digestibility (TOMD, ME, and partitioning factor (PF values were determined by in vitro gas production technique (IVGPT. Results: The CP content of non-leguminous fodders varied from 7.29% (sorghum to 9.51% (maize, but leguminous fodders had less variation in CP. Oilseed cakes/meals had high CP and ether extract (EE content than other feedstuffs except rice polish, which had 12.80% EE. Wheat straw contained highest fiber fractions than the other ingredients. ME content was highest in grains (wheat-12.02 MJ/kg and lowest in wheat straw (4.65 MJ/kg and other roughages. TDMD of grains and oilseed cakes/meals were higher than the fodders and agro-industrial by-products. The same trend was observed for TOMD. Conclusions: It was concluded that the energy feeds showed a great variation in chemical composition and ME content. The results of this study demonstrated that the kinetics of gas production of energy feed sources differed among themselves. Evaluation of various feedstuffs is helpful in balanced ration formulation for field animals and under farm conditions for better utilization of these commonly available feed resources.

  4. Influence of paragenetic factors on production and chemical composition of Paška sheep milk

    Directory of Open Access Journals (Sweden)

    Dubravka Samaržija

    2011-09-01

    Full Text Available Since the produced Paška sheep milk is entirely processed in Pag cheese, it is of great importance to ensure a uniform milk production of prescribed chemical composition and hygienic quality. In addition to genotype, as the most important factor, the production and quality of sheep milk is affected by numerous physiological factors, so the aim of this research was to determine the influence of paragenetic factors (stage and number of lactation on daily milk yield and chemical composition (total solids, milk fat, protein, casein, lactose, total solids non fat of Paška sheep milk. Three herds were chosen by random selection within the areas of Kolan and Caska, and survey was conducted on a total of 213 Paška sheep. Stage of lactation was divided to: the beginning (to 50th-day, the middle (from 51st till 100thday and the end (101st -day till dry out of lactation. Depending on the number of lactation, sheep were grouped into five groups (1st, 2nd, 3rd, 4th, 5th and others. A significant influence of stage and number of lactation on average daily milk yield and analysed chemical composition parameters was determined. The Paška sheep had the highest daily milk production in the mid lactation (773 g, and the third lactation (712 g recorded. At the end of lactation, total solids, milk fat, protein, casein, total solids non fat in milk were significantly higher than at the beginning and middle of lactation. The highest share of total solids, milk fat, protein and casein was determined in Paška sheep milk at 5th lactation and other lactations. Between the individual parameters significantcorrelation coefficients were determined.

  5. Some Chemical Compositional Changes in Miscanthus and White Oak Sawdust Samples during Torrefaction

    Directory of Open Access Journals (Sweden)

    J. Richard Hess

    2012-10-01

    Full Text Available Torrefaction tests on miscanthus and white oak sawdust were conducted in a bubbling sand bed reactor to see the effect of temperature and residence time on the chemical composition. Process conditions for miscanthus and white oak sawdust were 250–350 °C for 30–120 min and 220–270 °C for 30 min, respectively. Torrefaction of miscanthus at 250 °C and a residence time of 30 min resulted in a significant decrease in moisture—about 82.68%—but the other components—hydrogen, nitrogen, sulfur, and volatiles—changed only marginally. Increasing torrefaction temperatures to 350 °C with a residence time of 120 min further reduced the moisture content to 0.54%, with a significant decrease in the hydrogen, nitrogen, and volatiles by 58.29%, 14.28%, and 70.45%, respectively. Regression equations developed for the moisture, hydrogen, nitrogen, and volatile content of the samples with respect to torrefaction temperature and time have adequately described the changes in chemical composition based on R2 values of >0.82. Surface plots based on the regression equation indicate that torrefaction temperatures of 280–350 °C with residence times of 30–120 min can help reduce moisture, nitrogen, and volatile content from 1.13% to 0.6%, 0.27% to 0.23%, and 79% to 23%, with respect to initial values. Trends of chemical compositional changes in white oak sawdust are similar to miscanthus. Torrefaction temperatures of 270 °C and a 30 min residence time reduced the moisture, volatiles, hydrogen, and nitrogen content by about 79%, 17.88%, 20%, and 5.88%, respectively, whereas the carbon content increased by about 3.5%.

  6. Chemical composition and hygroscopic properties of aerosol particles over the Aegean Sea

    Directory of Open Access Journals (Sweden)

    S. Bezantakos

    2013-03-01

    Full Text Available The chemical composition and water uptake characteristics of sub-micrometer atmospheric particles in the region of the Aegean Sea were measured between 25 August and 11 September 2011 in the framework of the Aegean-Game campaign. High time-resolution measurements of the chemical composition of the particles were conducted using an airborne compact Time-Of-Flight Aerosol Mass Spectrometer (cTOF-AMS. These measurements involved two flights from the island of Crete to the island of Lemnos and back. A Hygroscopic Tandem Differential Mobility Analyzer (HTDMA located on the island of Lemnos was used to measure the ability of the particles to take up water. The HTDMA measurements showed that the particles were internally mixed, having hygroscopic growth factors that ranged from 1.00 to 1.59 when exposed to 85% relative humidity. When the aircraft flew near the ground station on Lemnos, the cTOF-AMS measurements showed that the organic volume fraction of the particles ranged from 43 to 56%. These measurements corroborate the range of hygroscopic growth factors measured by the HTDMA during that time. Good closure between HTDMA and cTOF-AMS measurements was achieved when assuming that the organic species were hydrophobic and had an average density that corresponds to aged organic species. Using the results from the closure study, the cTOF-AMS measurements were employed to determine a representative aerosol hygroscopic parameter κmix for the whole path of the two flights. Calculated κmix values ranged from 0.17 to 1.03 during the first flight and from 0.15 to 0.93 during the second flight. Air masses of different origin as determined by back trajectory calculations can explain the spatial variation in the chemical composition and κmix values of the particles observed in the region.

  7. Chemical diversity of Ziziphora clinopodioides: composition of the essential oil of Z. clinopodioides from Tajikistan.

    Science.gov (United States)

    Sharopov, Farukh S; Setzer, William N

    2011-05-01

    The chemical composition of the essential oils of Ziziphora clinopodioides Lam. from the aerial flowering parts, collected during two different years, were obtained by hydrodistillation and analyzed by gas chromatography - mass spectrometry. Forty-five components representing 100% and 94.7% of the total oil were identified. The main constituents of the essential oils were pulegone (72.8 and 35.0%), neomenthol (6.5 and 23.1%), menthone (6.2 and 13.3%), p-menth-3-en-8-ol (1.7 and 3.5%), piperitenone (2.6 and 1.1%) and piperitone (0.7 and 1.2%). A cluster analysis was carried out on the essential oil compositions of Z. clinopodioides. PMID:21615034

  8. Chemical characterization of smoke from the production process of wood-plastic composites

    Institute of Scientific and Technical Information of China (English)

    Wang Shi-fa; Zhang Ai-jun

    2007-01-01

    The chemical composition of unpleasant smell, emitted from the production process of wood-plastic composites using Manchurian ash sawdust (Fraxinus mandschurica Rupr.) and polypropylene powder as the raw material, was investigated. Wood sawdust and polypropylene powder were subjected to heat treatment to 290℃ during 8 min (the conditions were similar to those employed on an industrial scale). The emitted compounds were collected and analyzed by gas chromatography-mass spectrometry (GC-MS). The analytical results showed that the unpleasant smell was emitted from the pyrogenation of wood sawdust rather than from the polypropylene powder. Nine types of compounds (hydrocarbons, ethers, phenols, aldehydes, ketones, alcohols, acids and their derivatives, furan and its derivatives, and nitrogen-containing compounds) were collected in the gas phase during heating.Among those 126 components detected by GC-MS, 112 compounds were identified.

  9. Chemical composition of selected seaweeds from the Indian Ocean, KwaZulu-Natal coast, South Africa.

    Science.gov (United States)

    Magura, Judie; Moodley, Roshila; Jonnalagadda, Sreekantha B

    2016-08-01

    The chemical composition of three edible seaweeds (Codium capitatum, Hypnea spicifera and Sargassum elegans) and two inedible seaweeds (Halimeda cuneata and Spyridia hypnoides) from the Indian Ocean along the KwaZulu-Natal East Coast, South Africa were investigated as a function of seasonal variation. The proximate compositions of the edible seaweeds were determined. In edible seaweeds, the moisture level ranged from 85.4 to 89.5%, protein from 6.1 to 11.8%, lipids from 7.5 to 13.1% and carbohydrates from 37.8 to 71.9%. Elemental concentrations in the five studied seaweeds varied significantly with season (P health effects due to low concentrations of toxic elements. However, due to high levels of As in S. elegans, its consumption should be moderated to reduce dietary exposure to this toxic element. PMID:27153179

  10. Chemical compositions of the rhizome, leaf and stem oils from Malaysian Hornstedtia leonurus.

    Science.gov (United States)

    Jani, Nor Akmalazura; Sirat, Mohd Hasnah; Ali, NorAzah Mohamad; Aziz, Azrina

    2013-04-01

    The chemical compositions of the essential oil of the rhizome, leaf and stem of Hornstedtia leonurus Retz., collected from Negeri Sembilan, Malaysia,are reported for the first time. The essential oils were extracted using hydrodistillation and analyzed by gas chromatography (GC-FID) and gas chromatography/mass spectrometry (GC/MS). Seventeen (96.4%), thirteen (89.2%) and nine components (98.8%) were successfully identified from the rhizome, stem and leaf oils, respectively. Phenylpropanoids were found to be the major fraction, with methyleugenol being the most abundant compound in all oils with percentage compositions of 76.4% (rhizome), 80.3% (stem) and 74.5% (leaf). PMID:23738467

  11. On the visual binary υ Car and the chemical composition of its brighter component.

    Science.gov (United States)

    Samedov, Z. A.

    On the basis of the method for studying the composite spectrum of a double system, the following values of effective temperatures and surface gravities are obtained for the components of the visual binary υ Car: Teff = 7600±350K, lg g = 1.1±0.3 for the brighter component υ Car A, Teff = 23000±1600K, lg g = 3.3±0.1 for the fainter component υ Car B. By comparing the evolutionary calculations the author has found masses, radii, luminosities; the age is 107years. Using spectroscopic data, the microturbulent velocity and the chemical composition are studied in the atmosphere of υ Car A. The analysis of Ti II, Fe II, Cr II lines showed higher values in comparison with Fe I lines. The element abundances are defined using relatively weak lines, on average it is close to that of the Sun.

  12. Influence of Cold Stress on the Chemical Composition of Carcass to Mangalica pigs

    Directory of Open Access Journals (Sweden)

    Monica Pârvu

    2012-10-01

    Full Text Available The purpose of the experiment was to evaluate the chemical composition of meat of Mangalica and Large Whitepigs. The animals were raised in alternative system and exposed to 8-11°C. The initial weight at was 100 kg.Preparation of the carcass was made after the classical method. Linear measures were made on warm carcass. Thechemical composition of meat was determined to Longissimus dorsi muscle. The protein content of meat wasdeterminate by Tecator - Kyltec Auto Analyze and fat content by Soxtec System HT. Data were statistically analyzedby ANOVA method. Comparative with Large White breed, at Mangalica pigs, the fat thickness was significantlyhigher by 93% (p≤0.001 and the water content of meat was lower by 8.6%. The fat content of meat was higher with117% and cholesterol content was reduced with 32%, the differences being significant.

  13. Chemical composition and the acid-base properties of the InSb-ZnSe surface

    International Nuclear Information System (INIS)

    Acid-base properties and chemical composition of the surface of solid solutions and binary compounds of the system InSb-ZnSe powders and films 0.25-0.35 μm thick were studied using a complex of physicochemical methods. It was ascertained that the initial surface features largely acid properties with transition to low-basic ones in the series InSb → (InSb)x(ZnSe)1-x → ZnSe. There are two types of acid centers on the surface: the Lewis (electron-accepted) and Broensted ones (adsorbed water molecules and OH- groups). After thermal vacuum treatment the surface composition was similar to stoichiometric one

  14. Effect of chemical composition and alumina content on structure and properties of ceramic insulators

    Indian Academy of Sciences (India)

    Arman Sedghi; Nastaran Riahi-Noori; Naser Hamidnezhad; Mohammad Reza Salmani

    2014-04-01

    In the present work, six electrical porcelain compositions with different amount of alumina and silica have been prepared and fired in an industrial furnace at 1300°C. Density, porosity, bending strength and electrical strength were measured in the samples. In order to find a relationship between properties and sample microstructures, samples were analyzed by scanning electron microscope (SEM) and x-ray diffraction (XRD) techniques. The results showed that, with chemical composition of 53.5 wt.% SiO2 and 37.5 wt.% alumina, highest electrical strength of 21.97 kV/mm was achieved in fabricated electrical porcelains. Increasing amount of alumina up to 30 wt.% decreases quartz and cristobalite phases, but increases corundum phase 3 to 5 times. SEM observation revealed that dense particles and uniform distribution of long and thin needle shaped mullite are predominant in sample microstructures with highest electrical strength.

  15. Radiation-chemical solidification of compositions based on modified epoxide resins

    International Nuclear Information System (INIS)

    Possibilites of obtaining radiation-solidified compositions on the base of EhD-20 epoxide resin where the greatest part of epoxide groups is replaced by methacrylates, are studied. Coatings on the base of epoxide groups have been solidified with γ-rays and accelerated electrons in the atmosphere of the inert gas (electron energy 600 keV, radiation intensity 9.8 Mrad/min). It is shown that dimethylaminoethylmethacrylate is a catalyst of radiation solidification. Its optimum quantity in compositions is 5%. The dose neccessary for solidification decreases considerably (from 5-7 Mrad to 2 Mrad) and gel fraction maximum content increases. Physical and chemical properties of the above coating on the metal are investigated

  16. Chemical composition and antibacterial activity of essential oil of Nepeta graciliflora Benth. (Lamiaceae).

    Science.gov (United States)

    Sharma, Pankaj; Shah, G C; Sharma, Rabia; Dhyani, Praveen

    2016-06-01

    The chemical composition of the essential oil obtained from aerial parts of Nepeta graciliflora was analysed, for the first time, by GC-FID and GC-MS. A total of 27 compounds were identified, constituting over 91.44% of oil composition. The oil was strongly characterised by sesquiterpenes (86.72%), with β-sesquiphellandrene (28.75%), caryophyllene oxide (12.15%), α-bisabolol (8.97%), α-bergamotene (8.51%), β-bisabolene (6.33%) and β-Caryophyllene (5.34%) as the main constituents. The in vitro activity of the essential oil was determined against four micro-organisms in comparison with chloramphenicol by the agar well diffusion and broth dilution method. The oil exhibited good activity against all tested organisms. PMID:26140331

  17. Comparison of the chemical compositions and nutritive values of various pumpkin (Cucurbitaceae) species and parts.

    Science.gov (United States)

    Kim, Mi Young; Kim, Eun Jin; Kim, Young-Nam; Choi, Changsun; Lee, Bog-Hieu

    2012-02-01

    Pumpkins have considerable variation in nutrient contents depending on the cultivation environment, species, or part. In this study, the general chemical compositions and some bioactive components, such as tocopherols, carotenoids, and β-sitosterol, were analyzed in three major species of pumpkin (Cucurbitaceae pepo, C. moschata, and C. maxima) grown in Korea and also in three parts (peel, flesh, and seed) of each pumpkin species. C. maxima had significantly more carbohydrate, protein, fat, and fiber than C. pepo or C. moschata (P pumpkin was highest in C. pepo. The major fatty acids in the seeds were palmitic, stearic, oleic, and linoleic acids. C. pepo and C. moschata seeds had significantly more γ-tocopherol than C. maxima, whose seeds had the highest β-carotene content. C. pepo seeds had significantly more β-sitosterol than the others. Nutrient compositions differed considerably among the pumpkin species and parts. These results will be useful in updating the nutrient compositions of pumpkin in the Korean food composition database. Additional analyses of various pumpkins grown in different years and in different areas of Korea are needed. PMID:22413037

  18. Associated chemical and carbon isotopic composition variations in diamonds from Finsch and Premier kimberlite, South Africa

    International Nuclear Information System (INIS)

    The carbon isotopic composition of 66 inclusion-containing diamonds from the Premier kimberlite, South Africa, 93 inclusion-containing diamonds and four diamonds of two diamond-bearing peridotite xenoliths from the Finsch kimberlite, South Africa was measured. The data suggest a relationship between the carbon isotopic composition of the diamonds and the chemical composition of the associated silicates. For both kimberlites similar trends are noted for diamonds containing peridotite-suite inclusions (P-type) and for diamonds containing eclogite-suite inclusions (E-type): Higher delta13C P-type diamonds tend to have inclusions lower in SiO2, Al2O3, Cr2O3, MgO, Mg/(Mg + Fe) and higher in FeO and CaO. Higher delta13C E-type diamonds tend to have inclusions lower in SiO2, Al2O3, MgO, Mg/(Mg + Fe), Na2O, K2O, TiO2 and higher in CaO, Ca/(Ca + Mg). Consideration of a number of different models that have been proposed for the genesis of kimberlites, their zenoliths and diamonds shows that they are all consistent with the conclusion that in the mantle, regions exist that are characterized by different mean carbon isotopic compositions. (author)

  19. Silica-titania composite aerogel photocatalysts by chemical liquid deposition of titania onto nanoporous silica scaffolds.

    Science.gov (United States)

    Zu, Guoqing; Shen, Jun; Wang, Wenqin; Zou, Liping; Lian, Ya; Zhang, Zhihua

    2015-03-11

    Silica-titania composite aerogels were synthesized by chemical liquid deposition of titania onto nanoporous silica scaffolds. This novel deposition process was based on chemisorption of partially hydrolyzed titanium alkoxides from solution onto silica nanoparticle surfaces and subsequent hydrolysis and condensation to afford titania nanoparticles on the silica surface. The titania is homogeneously distributed in the silica-titania composite aerogels, and the titania content can be effectively controlled by regulating the deposition cycles. The resultant composite aerogel with 15 deposition cycles possessed a high specific surface area (SSA) of 425 m(2)/g, a small particle size of 5-14 nm, and a large pore volume and pore size of 2.41 cm(3)/g and 18.1 nm, respectively, after heat treatment at 600 °C and showed high photocatalytic activity in the photodegradation of methylene blue under UV-light irradiation. Its photocatalytic activity highly depends on the deposition cycles and heat treatment. The combination of small particle size, high SSA, and enhanced crystallinity after heat treatment at 600 °C contributes to the excellent photocatalytic property of the silica-titania composite aerogel. The higher SSAs compared to those of the reported titania aerogels (silica-titania aerogels promising candidates as photocatalysts. PMID:25664480

  20. The puzzling chemical composition of GJ 436b's atmosphere: influence of tidal heating on the chemistry

    CERN Document Server

    Agundez, M; Selsis, F; Iro, N

    2013-01-01

    The dissipation of the tidal energy deposited on eccentric planets may induce a heating of the planet that affects its atmospheric thermal structure. Here we study the influence of tidal heating on the atmospheric composition of the eccentric (e = 0.16) "hot Neptune" GJ 436b, for which inconclusive chemical abundances are retrieved from multiwavelength photometric observations carried out during primary transit and secondary eclipse. We build up a one-dimensional model of GJ 436b's atmosphere in the vertical direction and compute the pressure-temperature and molecular abundances profiles for various plausible internal temperatures of the planet (up to 560 K) and metallicities (from solar to 100 times solar), using a radiative-convective model and a chemical model which includes thermochemical kinetics, vertical mixing, and photochemistry. We find that the CO/CH4 abundance ratio increases with metallicity and tidal heating, and ranges from 1/20 to 1000 within the ranges of metallicity and internal temperature ...

  1. Changes of Chemical Composition and Crystalline of Compressed Chinese Fir Wood in Heating Fixation

    Institute of Scientific and Technical Information of China (English)

    Tang Xiaoshu; Zhao Guangjie; Nakao Tetsuya

    2004-01-01

    The changes in relative crystalline, chemical composition and internal structure of compressed Chinese fir wood after different heating fixations were found strictly related to fixation conditions. The compressed wood powders were fixed either by heating at different temperatures all resulting in a 10% recovery, or by incubating at 180 °C for different periods with subsequent recovery levels. Both X-ray diffraction and infrared absorption of those samples have been measured. Relative crystalline increases at early stage of heating fixation, and then decreased gradually. Hemicellulose and lignin decomposition were induced by the fixation process, especially at 180 °C, and lignin was degraded actively. Furthermore, absorbed water was lost after heating, but cellulose did not change markedly. Although different fixation pathways can result in the same recovery level, the major chemical reactions underlying them vary, which is consistent with the difference of fixation mechanisms.

  2. Study on exploitation of Jerusalem artichoke bulbs in relation to chemical composition

    Directory of Open Access Journals (Sweden)

    Sorina Ropciuc

    2014-11-01

    Full Text Available Abstract Jerusalem artichoke (Helianthus tuberosus L. known in USA also as sunchoke, is a perennial plant, well-adapted to humid and cold climats, nonpretencious to soil and with good yield increase. The bulbs are the eatable part that grows in the ground that have certain similitudes with the potato. The value of Jerusalem artichoke as a technical and medical vegetable is based on the chemical composition of the plant. The bulbs of the Jerusalem artichoke harvested in autumn have been sensorially and chemically analyzed along the deposition during the cold season. Measurements were made on the light brown variety with a slightly elongated shape. The low mass loss during depostion, the high content of reducing sugar (4.7- 6.12% and total carbohydrates (94.27-96.18% enable their successful use in the functional food and for the production of alcohol.

  3. Physical and chemical properties and compositions of liquid effluents of a nuclear power reactor

    International Nuclear Information System (INIS)

    Behaviours of the released radioactive materials from a nuclear power plant to the marine environment depend largely on their physical and chemical properties. It is therefore important to grasp the compositions of the liquid effluents. From this point of view, some kinds of drainwater of a BWR plant were sampled. These samples are the laundry drain water at charcoal bed inlet and outlet, and the floor drain water. Suspended solids were separated from these samples physically with the step filtration method and ions chemically with the ion exchange resin. Radioactivity of Co-60, Mn-54 and Cs-137 was measured with γ spectrometer. Suspended solids of the laundry drain samples were also analysed with the instrumental methods (differential thermal analysis, x-ray diffraction analysis and x-ray fluorescence analysis)

  4. Chemical composition, stratigraphy, and depositional environments of the Black River Group (Middle Ordovician), southwestern Ohio.

    Science.gov (United States)

    Stith, David A.

    1981-01-01

    The chemical composition and stratigraphy of the Black River Group in southwestern Ohio were studied. Chemical analyses were done on two cores of the Black River from Adams and Brown Counties, Ohio. These studies show that substantial reserves of high-carbonate rock are present in the Black River at depths of less than 800 ft, in proximity to Cincinnati and the Ohio River. Stratigraphic studies show that the Black River Group has eight marker beds in its middle and upper portions and three distinct lithologic units in its lower portion; these marker beds and units are present throughout southwestern Ohio. The Black River Group correlates well with the High Bridge Group of Kentucky. Depositional environments of the Black River are similar to those of the High Bridge and to present-day tidal flats in the Bahamas.-Author

  5. Antioxidant capacity and chemical composition in seeds rich in omega-3: chia, flax, and perilla

    Directory of Open Access Journals (Sweden)

    Sheisa Cyléia Sargi

    2013-09-01

    Full Text Available The chemical composition and antioxidant capacity of five seeds, chia, golden flax, brown flax, white perilla, and brown perilla, were determined. The chemical properties analyzed included moisture, ash, crude protein, carbohydrates, total lipids, fatty acids, and antioxidant capacity (ABTS•+, DPPH•, and FRAP. The results showed the highest amounts of protein and total lipids in brown and white perilla. Perilla and chia showed higher amounts of alpha-linolenic fatty acid than those of flaxseed varieties, ranging between 531.44 mg g-1 of lipids in brown perilla, 539.07 mg g-1 of lipids in white perilla, and 544.85 mg g-1 of lipis in chia seed. The antioxidant capacity of the seeds, evaluated with ABTS•+, DPPH• , and FRAP methods, showed that brown perilla had greater antioxidant capacity when compared with white perilla, flax, and chia seeds.

  6. HONEYDEW HONEY: CORRELATIONS BETWEEN CHEMICAL COMPOSITION, ANTIOXIDANT CAPACITY AND ANTIBACTERIAL EFFECT

    Directory of Open Access Journals (Sweden)

    OTILIA BOBIS

    2013-12-01

    Full Text Available Selected physico-chemical parameters, total polyphenols, flavonoids, antioxidant and antibacterial activity of honeydew honey samples from Romanian were determined. Regarding the chemical composition, analysed honey samples framed in this type of honey, phenolic content, determined as gallic acid equivalents, presented a mean value of 116.45mg GAE/100 g honey. Total flavonoid content expressed as quercetin equivalents, was 1.53 mg in honeydew honey. Antioxidant activity expressed as % inhibition of a solution of DPPH, ranged between 47.84 and 62.99%. The concentration of honey that inhibit with 50% the DPPH solution was established to be 16.16%. 10 strains of Staphylococcus aureus presented different inhibition percentages when were treatred with a solution of honey. In conclusion, Honeydew honey could be recommended to complement other polyphenol source in human diet and also used in medical treatment.

  7. [Comparison of green coffee beans volatiles chemical composition of Hainan main area].

    Science.gov (United States)

    Hu, Rong-Suo; Chu, Zhong; Gu, Feng-Lin; Lu, Min-Quan; Lu, Shao-Fang; Wu, Gui-Ping; Tan, Le-He

    2013-02-01

    Chemical component of Hainan green coffee beans was analyzed with solid phase microextraction-gas chromatography-mass spectrometry, and the discrepancy between two green coffee beans was differentiated through the spectrum database retrieval and retention index of compound characterization. The experimental results show that: the chemical composition of Wanning coffee beans and Chengmai coffee beans is basically the same. The quantity of analyzed compound in Wanning area coffee is 91, and in Chengmai area coffee is 106, the quantity of the same compound is 66, and the percent of the same component is 75.52%. The same compounds accounted for 89.86% of the total content of Wanning area coffee, and accounted for 85.70% of the total content of Chengmai area coffee. PMID:23697152

  8. Color and chemical composition and of green corn produced under organic and conventional conditions

    Directory of Open Access Journals (Sweden)

    Lucineia de Pinho

    2011-06-01

    Full Text Available The present study aimed to evaluate the chemical properties of green corn, grown in both organic and conventional farming systems, using a completely randomized factorial design. Four corn varieties (AG 1051, BR 106, SWB 551 and VIVI of green corn kernels were evaluated for color, proximate composition, total calories, carotenoids and bioactive amines. The farming system affected some chemical and physical characteristics of green corn, but this effect was dependent upon variety. In general, organic green corn kernels were reddish (a* color component and had higher levels of β-carotene compared to the conventional ones, suggesting that these characteristics are related. Moreover, organic green corn had higher levels of total carbohydrates and total energy compared to conventional varieties. On the other hand, crude fiber levels were higher in conventional grains - an unexpected result that deserves further investigation. Finally, the levels of cadaverine and spermine bioactive amines were not affected either by the corn variety or by the farming system.

  9. Chemical Composition of the RS CVn-type Star 29 Draconis

    CERN Document Server

    Barisevi\\vcius, G; Berdyugina, S; Chorniy, Y; Ilyin, I

    2011-01-01

    Photospheric parameters and chemical composition are determined for the single-lined chromospherically active RS CVn-type star 29 Draconis (HD 160538). From the high resolution spectra obtained on the Nordic Optical Telescope, abundances of 22 chemical elements, including the key elements such as 12C, 13C, N and O, were investigated. The differential line analysis with the MARCS model atmospheres gives Teff=4720 K, log g=2.5, Fe/H]=-0.20, [C/Fe]=-0.14, [N/Fe]=0.08, [O/Fe]=-0.04, C/N=2.40, 12C/13C=16. The low value of the 12C/13C ratio gives a hint that extra mixing processes in low-mass chromospherically active stars may start earlier than the theory of stellar evolution predicts.

  10. Chemical composition and functional properties of starch extracted from the pejibaye fruit (Bactris gasepaes Kunth.

    Directory of Open Access Journals (Sweden)

    Biano Alves de Melo Neto

    2015-01-01

    Full Text Available This study aimed to establish the chemical composition and functional properties of the starch extracted from the pejibaye fruit (Bactris gasepaes Kunth.. The chemical characterization was evaluated from the determination of starch, amylose, amylopectin, total lipid, protein, ash, moisture and water activity. The water absorption index and the water solubility index were calculated for temperatures between 25 and 90ºC. Low contents of ash and protein were found. The studied starch has 14% moisture, according to the established by law. The water activity value was 0.55, which ensures its microbiological stability. A range of gelatinization between 65 to 70ºC was observed, close to the one of commercial starches. The solubility rate in water was 0.6119% and the absorption rate in water was 1.8252%. These results demonstrated that the starch from the pejibaye fruit has important characteristics for use in the food industry.

  11. Assessment of Water and Sediment Physical-Chemical Composition in the West Coast of Maracaibo Lake

    Directory of Open Access Journals (Sweden)

    Jorge Moronta-Riera

    2016-05-01

    Full Text Available The objective of this investigation was to determine the physical and chemical composition of the water streams and sediments of the Maracaibo Lake in three sampling areas located in Tía Juana, Lagunillas and Ceuta in order to know the level of contamination and assess water quality based on permissible values established by the 883 Decree. The results indicate that the overall hydrocarbon concentrations in the water and sediments are above permissible levels. It is concluded that petroleum prospection is the root cause of the lake contamination.

  12. Surface contamination effects on leaf chemical composition in the Atlantic Forest

    International Nuclear Information System (INIS)

    The exogenous material that adheres to the leaf surface affects the elemental composition of the plant itself, thereby constituting one of the major error sources in plant analysis. The present work investigated the surface contamination of leaves from the Atlantic Forest. Instrumental neutron activation analysis (INAA) was applied to assess the efficiency of leaf EDTA-washing. Chemical element concentrations were corrected using Sc (soil tracer) since resuspended soil is the main source of contamination in leaves. As a result, EDTA-washing should be used mainly for the evaluation of terrigenous elements, while the Sc-corrected concentrations are considered satisfactory for the other elements. (author)

  13. Chemical composition and biological activities of essential oils of Azadirachta indica A. Juss.

    OpenAIRE

    S S El-Hawary; M E El-Tantawy; M. A. Rabeh; W K Badr

    2013-01-01

    Summary. Essential oils of Neem, Azadirachta indica A. Juss. (family Meliaceae) leaves and flowers were prepared by hydrodistillation method. The chemical composition of the oil samples was investigated by GC/MS. Hydrocarbon constituted 85.36% of the leaves oil .The major compounds were β-Elemene (33.39%), γ- Elemene (9.89%), Germacrene D (9.72%), Caryophyllene (6.8%) and Bicyclogermacrene (5.23%) while the percent of the oxygenated compounds were (5.04%) mainly attributed to sesquiterpene ox...

  14. Chemical composition of lipids in brewer's spent grain: A promising source of valuable phytochemicals

    OpenAIRE

    Río Andrade, José Carlos del; Prinsen, Pepijn; Gutiérrez Suárez, Ana

    2013-01-01

    Brewer’s spent grain (BSG) is an important by-product from the brewing process produced in high amounts worldwide. BSG is rich in carbohydrates, lignin, proteins and lipids. In this work, the chemical composition of the lipids in BSG was studied in detail by gas chromatography and mass spectrometry. The predominant lipids were triglycerides (67% of total extract), followed by a series of free fatty acids (18%). Lower amounts of monoglycerides (1.6%) and diglycerides (7.7%) were also identifie...

  15. RESEARCH ON CHEMICAL COMPOSITION AND MICROSTRUCTURE OF NEWLY-DEVELOPED HIGH STRENGTH AND HIGH ELONGATION STEELS

    Institute of Scientific and Technical Information of China (English)

    Y. Chen; X. Chen; A.M. Guo; D.X. Luo; B.F. Xu; Z.X. Yuan; P.H. Li; S.K. Pu; S.B. Zhou

    2003-01-01

    The different chemical composition of silicon and manganese as well as different re-tained austenite fraction ranged from 4% to 10% of the high strength and high elon-gation steels were studied in the paper. The dislocations and carbon concentrationin retained austenite were observed by a transmission electron microscope and anelectric probe analyzer, respectively. The experimental results showed that silicon andmanganese are two fundamental alloying elements to stabilize austenite effectively butretaining austenite in different mechanisms. Meanwhile, the cooling processing playedan important role in controlling the fraction of retained austenite of the hot-rolledhigh strength and high plasticity steels.

  16. Effect of Chemical Composition of Honey on Cream Formation in Honey Lemon Tea

    OpenAIRE

    J. Hategekimana; J.G. Ma, Y. Li, E. Karangwa, W. Tang and F. Zhong

    2011-01-01

    The aim of this study was to assess the effect of chemical composition of honey and environmental factors such as pH, storage temperature and ionic strength on cream formation in honey lemon tea drink. The results showed that minerals, Ca2+ and Mg2+ were involved in cream formation while Fe2+ participated in changing color to tar black at pH 4.12 and above. Honey rich in polyphenols and proteins increased the cream to 2.51%. High proline content (0.506 mg/g) induced creaming in GH (Germany Ho...

  17. Chemical composition and mosquito repellent activity of the essential oil of Plectranthus incanus link

    OpenAIRE

    Pal Mahesh; Kumar Anil; Tewari Krishna Shri

    2011-01-01

    The chemical composition of the essential oil obtained from the leaves of Plectranthus incanus Link, with the yield of 0.6% (w/v), was analyzed by GC and GC/MS. A total of 16 constituents, representing 95.2% of the oil, were identified. The major components of the oil were fenchone (6.0%), piperitone oxide (32.4%), piperitenone (3.0%) and piperitenone oxide (41.5%). The repellent activity of the volatile oil at different concentrations was measured by the protection period against the b...

  18. Morphology, chemical compositions and size distribution of rare earth oxides in pure iron

    Institute of Scientific and Technical Information of China (English)

    2003-01-01

    The pure iron was melted and deoxidized by metallic Al and rare earth elements La, Ce and Y respectively at 1600℃ in avertical resistance furnace. The morphology, chemical composition and size distribution of the inclusions in deoxidized liquid ironhave been investigated by using of SEM and image-analysis techniques. The investigated results show that the deoxidation productsin molten iron are complex inclusions of rare earth oxide or Al2O3 combined with FeO finely distributed. The proper holding timeand rapid cooling rate can make inclusions finer. La, Y and Al are more effective than Ce for obtaining finely distributed inclusions.

  19. Signal of New Physics and Chemical Composition of Matter in Core Crossing Neutrinos

    OpenAIRE

    Liao, Wei(Institute of Modern Physics, School of Science, East China University of Science and Technology, Shanghai, China)

    2008-01-01

    We consider non-standard matter effect in flavor conversion of neutrinos crossing the core of the Earth. We show that oscillation of core crossing neutrinos with $E \\gsim 0.5$ GeV can be well described by a first order perturbation theory. We show that due to non-standard matter effect varying chemical composition in the Earth can modify the neutrino flavor conversion by 100%. Effects of CP violating phases in non-standard Neutral Current interactions are emphasized in particular.

  20. The dissimilar chemical composition of the planet-hosting stars of the XO-2 binary system

    OpenAIRE

    Ramirez, I.; S.Khanal; Aleo, P.; Sobotka, A.; Liu, F.; Casagrande, L.; Melendez, J.; Yong, D.; Lambert, D. L.; Asplund, M.

    2015-01-01

    Using high-quality spectra of the twin stars in the XO-2 binary system, we have detected significant differences in the chemical composition of their photospheres. The differences correlate strongly with the elements' dust condensation temperature. In XO-2N, volatiles are enhanced by about 0.015 dex and refractories are overabundant by up to 0.090 dex. On average, our error bar in relative abundance is 0.012 dex. We present an early metal-depletion scenario in which the formation of the gas g...

  1. The chemical composition, fermentation profile, and microbial populations in tropical grass silages

    OpenAIRE

    João Paulo Sampaio Rigueira; Odilon Gomes Pereira; Karina Guimarães Ribeiro; Hilário Cuquetto Mantovani; Mariele Cristina Nascimento Agarussi

    2013-01-01

    The objective of this study was to evaluate the fermentation profile, chemical composition and microbial population and losses in the silages of signalgrass and Mombasa grass fertilized with the following levels of nitrogen (N): 0, 30, 60 and 90 kg/ha. The grasses were harvested at 70 days of regrowth, chopped and then ensiled in laboratory silos that had 20 kg of capacity and a snap-top cover and were fitted with Bunsen valves. Before ensiling, samples of the plants were used for the isolati...

  2. The chemical composition of the snow in urban environment in the Far North

    Directory of Open Access Journals (Sweden)

    Saltan N.V.

    2015-06-01

    Full Text Available The paper presents experimental data of the chemical composition of snow cover of squares and streets in the polar cities. It has been revealed that the natural ratio of cations and anions is modified in the snow. Comparative assessment of the levels of concentration of metals in the snow showed higher values in squares than on the streets. It has been shown that the main share in the pollution of snow by heavy metals belongs to the dust of anthropogenic origin

  3. Chemical Composition and Possible in Vitro Phytotoxic Activity of Helichrsyum italicum (Roth Don ssp. italicum

    Directory of Open Access Journals (Sweden)

    Vincenzo De Feo

    2011-09-01

    Full Text Available The chemical composition of the essential oil of Helichrysum italicum (Roth Don ssp. italicum, collected in the National Park of Cilento and Diano Valley, Southern Italy, was studied by means of GC and GC/MS. Forty four compounds of 45 constituents were identified in the oil, mainly oxygenated sesquiterpenes. The essential oil was evaluated for its potential in vitro phytotoxic activity against germination and early radicle elongation of radish and garden cress. The radicle elongation of radish was significantly inhibited at the highest doses tested, while germination of both seeds was not affected.

  4. Chemical composition and possible in vitro phytotoxic activity of Helichrsyum italicum (Roth) Don ssp. italicum.

    Science.gov (United States)

    Mancini, Emilia; De Martino, Laura; Marandino, Aurelio; Scognamiglio, Maria Rosa; De Feo, Vincenzo

    2011-01-01

    The chemical composition of the essential oil of Helichrysum italicum (Roth) Don ssp. italicum, collected in the National Park of Cilento and Diano Valley, Southern Italy, was studied by means of GC and GC/MS. Forty four compounds of 45 constituents were identified in the oil, mainly oxygenated sesquiterpenes. The essential oil was evaluated for its potential in vitro phytotoxic activity against germination and early radicle elongation of radish and garden cress. The radicle elongation of radish was significantly inhibited at the highest doses tested, while germination of both seeds was not affected. PMID:21904272

  5. CHEMICAL COMPOSITION AND ANTIOXIDANT ACTIVITY OF ESSENTIAL OIL FROM CURCUMA AMADA ROXB.

    OpenAIRE

    Vishnupriya M; Nishaa.S; Sasikumar.J.M; Teepica Priya Darsini.D; Hephzibah Christabel P; Gopalakrishnan V.K

    2012-01-01

    This study was designed to examine the chemical composition and in vitro antioxidant activity of essential oil of Curcuma amada Roxb. The GC- MS analysis of the oil resulted in the identification of 12 compounds. β-myrcene (63.85%) and α-asarone (30.27%) were the two major components identified. The sample was subjected to screening for their possible antioxidant activity by using 2, 2-diphenyl-1-picrylhydrazyl (DPPH) radical, ABTS radical, Ferric reducing antioxidant power and β-Carotene ble...

  6. PHYSICAL, CHEMICAL, AND LIPID COMPOSITION OF JUÇARA (EUTERPE EDULIS MART.) PULP

    OpenAIRE

    Paula Porrelli Moreira da SILVA; Leandro Francisco do CARMO; Guilherme Mei SILVA; Mayra Fernanda SILVEIRA-DINIZ; Casemiro, Renata Cristina; Spoto, Marta Helena Fillet

    2013-01-01

    Juçara palm (Euterpe edulis Martius) is native to the Brazilian Atlantic Forest and is an endangered species due to intensive exploration to produce hearts of palm. In the last few years, juçara plantation has been implemented for fruit production and pulp extraction, similar to açaí (Euterpe oleracea Mart.). The objective of this study was to assess the physical, chemical, and lipid composition of juçara pulp, in order to establish the exact measures of its quality ai...

  7. The influence of chemical composition on the properties and structure Al-Si-Cu(Mg) alloys

    OpenAIRE

    M. Kaczorowski; A. Krzyńska

    2007-01-01

    The mechanical properties of different chemical composition AlSiCuMg type cast alloys after precipitation hardening are presented. The aim of the study was to find out how much the changes in chemistry of aluminum cast alloys permissible by EN-PN standards may influence the mechanical properties of these alloys. Eight AlSi5Cu3(Mg) type cast alloys of different content alloying elements were selected for the study. The specimens cut form test castings were subjected to precipitation hardening ...

  8. Chemical composition of the essential oils for AnthemisMelampodina from North Saudi Arabia

    OpenAIRE

    Jehan Al-humaidi

    2015-01-01

    The chemical composition of essential oil of Anthemsmelampodinais determined by GC/MS. The oil was obtained by hydro-distillation and SPME extraction methodsIn the SPME method, a total of 41 constituents were identified monoterpene hydrocarbons (88.89%) were the main class of compounds detected in the SPME method with b-pinene(35.29%), trans-ocimene(23.96%) andterpinolene(15.78%) being detected as the main constituents. On the other hand, hydro-distilled oil was rich in oxygenated sesquiterpe...

  9. Chemical composition of the essential oils for AnthemisMelampodina from North Saudi Arabia

    Directory of Open Access Journals (Sweden)

    Jehan Al-humaidi

    2015-12-01

    Full Text Available The chemical composition of essential oil of Anthemsmelampodinais determined by GC/MS. The oil was obtained by hydro-distillation and SPME extraction methodsIn the SPME method, a total of 41 constituents were identified monoterpene hydrocarbons (88.89% were the main class of compounds detected in the SPME method with b-pinene(35.29%, trans-ocimene(23.96% andterpinolene(15.78% being detected as the main constituents. On the other hand, hydro-distilled oil was rich in oxygenated sesquiterpene(31.22%.

  10. 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

  11. Chemical composition and antimicrobial activity of the essential oil of Hyptis pectinata (l.) Poit

    International Nuclear Information System (INIS)

    Essential oil was extracted from leaves of Hyptis pectinata using hydrodistillation, and its composition determined using GC-FID and GC-MS. Chemical analysis showed that there was a predominance of sesquiterpenes, of which b-caryophyllene (18.34%), caryophyllene oxide (18.00%) and calamusenone (24.68%) were measured for the first time in the genus Hyptis. Twenty-one compounds were identified, and calamusenone was isolated using preparative thin layer chromatography with a silica gel plate (60 PF254). The minimal inhibitory concentration (MIC) and minimal microbicidal concentration (MMC) were determined for various pathogenic microorganisms. H. pectinata oil was most effective against Gram (+) bacteria and yeasts. (author)

  12. Chemical and nutritional composition of some common foods in Abeokuta, Nigeria

    OpenAIRE

    Silifat Ajoke Sanni; Clara Raquel Bernstein Oguntona; Lateef Oladimeji Sanni

    1999-01-01

    Chemical composition of seven common foods viz. cooked rice, cooked beans, cooked yams, cooked fufu, fried fish, stew, and vegetable soup, sold by the selected (147) vendors in Abeokut, were investigated. Descriptive statistics was used to analyse the collected data. The results of the proximate analysis of food samples showed that the mean moisture content of the street foods ranged from 44.87% in fried fish to 72.43% in cooked fufu. Protein content varied from 0.03% in cooked fufu to 14.47%...

  13. Chemical Composition and Antigerminative Activity of the Essential Oils from Five Salvia Species

    OpenAIRE

    Vincenzo De Feo; Enrica De Falco; Emilia Mancini; Graziana Roscigno; Laura De Martino

    2010-01-01

    The chemical composition of the essential oils of Salvia africana L., Salvia elegans Vahl, Salvia greggii A. Gray, Salvia mellifera Green and Salvia munzii Epling, cultivated in Eboli (Salerno, Southern Italy), was studied by means of GC and GC-MS analyses. In all, 88 compounds were identified, 54 for S. africana, accounting for 95.4% of the total oil, 55 for S. elegans (92.9%), 50 for S. greggii (96.9%), 54 for S. mellifera (90.4%) and 47 for S. munzii (97.5%), respectively. In S. africana,t...

  14. Chemical composition and dry matter digestibility of sugar cane oxide treated with calcium

    OpenAIRE

    C.O. Romão; G.G.P. Carvalho; V.M. Leite; Santos, A. S.; D.M.T. Chagas; O.L. Ribeiro; P.A. Oliveira; Magalhães, A F; A.J.V. Pires

    2014-01-01

    The aim of this study was to identify the most adequate level of calcium oxide (CaO) in the treatment of sugar cane by evaluating the chemical composition and in vitro digestibility of dry matter. The sugar cane was homogenized with CaO levels 0, 0.75, 1.5, 2.25, 3.0, 3.75 and 4.5%, in natura matter, for 24 hours. The dry matter and mineral matter increased, while the organic matter of the sugar cane decreased (P

  15. Correlations between chemical composition and provenance of Justino site ceramics by INAA

    International Nuclear Information System (INIS)

    Instrumental neutron activation analysis (INAA), have been used for the definition of compositional groups of potteries from Justino site, Brazil, according to the chemical similarities of ceramic paste. The outliers were identified by means of robust Mahalanobis distance. The temper effect in the ceramic paste was studied by means of modified Mahalanobis filter. The results were interpreted by means of cluster, principal components, and discriminant analyses. This work provides contributions for the reconstruction of the prehistory of baixo Sao Francisco region, and for the reconstitution of the Brazilian Northeast ceramist population of general frame. (author)

  16. Physico-Chemical Properties, Composition and Oxidative Stability of Camelina sativa Oil

    OpenAIRE

    Abramovič, Helena; Abram, Veronika

    2005-01-01

    Camelina sativa is a cruciferous oilseed plant. With the aim of describing the general characteristics of the oil obtained from the seeds of plants grown in Slovenia and of comparing it to camelina oil from other countries we determined some physico-chemical properties, fatty acid composition, iodine and saponification value and followed its oxidative stability under different storage conditions. The density at 20 °C was (0.927 0.0001) g/cm3 and the refractive index reached 1.4756 0.0001 at...

  17. Chemical composition and antimicrobial activity of essential oils of Ocimum canum Sims. and Ocimum selloi Benth.

    OpenAIRE

    Jeferson C. Nascimento; Luiz C. A. Barbosa; Vanderlucia F. Paula; David, Jorge M.; Renato Fontana; Luiz A.M. Silva; Robson S. França

    2011-01-01

    This work describes the chemical composition and antimicrobial activity of the volatile oils of Ocimum canum and Ocimum selloi, both occurring in Jequié/BA, northeastern Brazil. The plants were collected in the winter/2005 andsummer/2006, the oils extracted by steam distillation and further analyzed by GC-MS. A total of 30 and 31 compounds was identified from the oils of O. selloi and O. canum, respectively. It was observed that the oil content of O. canum showed variation during the seasons,...

  18. Load transfer and mechanical properties of chemically reduced graphene reinforcements in polymer composites

    International Nuclear Information System (INIS)

    We report load transfer and mechanical properties of chemically derived single layer graphene (SLG) as reinforcements in poly (dimethyl) siloxane (PDMS) composites. Shear mixing reduced graphene sheets in polymers resulted in a marked decrease of the 2D band intensity due to doping and functionalization. Raman G mode shifts of 11.2 cm−1/% strain in compression and 4.2 cm−1/% strain in tension are reported. Increases in elastic modulus of PDMS by ∼42%, toughness by ∼39%, damping capability by ∼673%, and strain energy density of ∼43% by the addition of 1 wt% SLG in PDMS are reported. (paper)

  19. ON THE MORPHOLOGY AND CHEMICAL COMPOSITION OF THE HR 4796A DEBRIS DISK

    Energy Technology Data Exchange (ETDEWEB)

    Rodigas, Timothy J.; Weinberger, Alycia [Department of Terrestrial Magnetism, Carnegie Institution of Washington, 5241 Broad Branch Road, NW, Washington, DC 20015 (United States); Stark, Christopher C. [NASA Goddard Space Flight Center, Exoplanets and Stellar Astrophysics Laboratory, Code 667, Greenbelt, MD 20771 (United States); Debes, John H.; Chen, Christine [Space Telescope Science Institute, Baltimore, MD 21218 (United States); Hinz, Philip M.; Close, Laird; Smith, Paul S.; Males, Jared R.; Skemer, Andrew J.; Follette, Katherine B.; Morzinski, Katie; Wu, Ya-Lin; Schneider, Glenn [Steward Observatory, The University of Arizona, 933 North Cherry Avenue, Tucson, AZ 85721 (United States); Puglisi, Alfio; Briguglio, Runa; Esposito, Simone; Pinna, Enrico; Riccardi, Armando; Xompero, Marco, E-mail: trodigas@carnegiescience.edu [INAF-Osservatorio Astrofisico di Arcetri, Largo E. Fermi 5, I-50125, Firenze (Italy)

    2015-01-10

    We present resolved images of the HR 4796A debris disk using the Magellan adaptive optics system paired with Clio-2 and VisAO. We detect the disk at 0.77 μm, 0.91 μm, 0.99 μm, 2.15 μm, 3.1 μm, 3.3 μm, and 3.8 μm. We find that the deprojected center of the ring is offset from the star by 4.76 ± 1.6 AU and that the deprojected eccentricity is 0.06 ± 0.02, in general agreement with previous studies. We find that the average width of the ring is 14{sub −2}{sup +3}% (11.1{sub −1.6}{sup +2.4} AU), also comparable to previous measurements. Combining our new scattered light data with archival Hubble Space Telescope images at ∼0.5-2 μm, along with previously unpublished Spitzer/MIPS thermal emission data and all other literature thermal data, we set out to constrain the chemical composition of the dust grains. After testing 19 individual root compositions and more than 8400 unique mixtures of these compositions, we find that good fits to the scattered light alone and thermal emission alone are discrepant, suggesting that caution should be exercised if fitting to only one or the other. When we fit to both data sets simultaneously, we find that silicates and organics are generally the most favored, while large abundances of water ice are usually not favored. These results suggest the HR 4796A dust grains are similar to interstellar dust and solar system comets, though improved modeling is necessary to place better constraints on the exact chemical composition of the dust.

  20. ON THE MORPHOLOGY AND CHEMICAL COMPOSITION OF THE HR 4796A DEBRIS DISK

    International Nuclear Information System (INIS)

    We present resolved images of the HR 4796A debris disk using the Magellan adaptive optics system paired with Clio-2 and VisAO. We detect the disk at 0.77 μm, 0.91 μm, 0.99 μm, 2.15 μm, 3.1 μm, 3.3 μm, and 3.8 μm. We find that the deprojected center of the ring is offset from the star by 4.76 ± 1.6 AU and that the deprojected eccentricity is 0.06 ± 0.02, in general agreement with previous studies. We find that the average width of the ring is 14−2+3% (11.1−1.6+2.4 AU), also comparable to previous measurements. Combining our new scattered light data with archival Hubble Space Telescope images at ∼0.5-2 μm, along with previously unpublished Spitzer/MIPS thermal emission data and all other literature thermal data, we set out to constrain the chemical composition of the dust grains. After testing 19 individual root compositions and more than 8400 unique mixtures of these compositions, we find that good fits to the scattered light alone and thermal emission alone are discrepant, suggesting that caution should be exercised if fitting to only one or the other. When we fit to both data sets simultaneously, we find that silicates and organics are generally the most favored, while large abundances of water ice are usually not favored. These results suggest the HR 4796A dust grains are similar to interstellar dust and solar system comets, though improved modeling is necessary to place better constraints on the exact chemical composition of the dust

  1. Evaluation of beetroot (Beta vulgaris L. leaves during its developmental stages: a chemical composition study

    Directory of Open Access Journals (Sweden)

    Polyana Batoqui França Biondo

    2014-03-01

    Full Text Available Beetroot leaves (Beta vulgaris L. are commonly cut off and discarded before using its bulb due to lack of knowledge of how to use them. Aiming at using these leaves, in the present study, in natura and dehydrated beetroot leaves were chemically characterized in terms of fatty acid composition, proximate composition, minerals, total phenolic compounds (TPC, and antioxidant activity by DPPH• in different stages (60, 80, and 100 days of development. The beetroot leaves showed significant levels of protein and lipids in all developmental stages, and all proximate composition nutrients decreased during these maturation stages; the highest content was observed at 60 days. The Fe content decreased during the developmental stages (from 342.75 to 246.30 mg.kg-1, while the content of K increased (from 13,367.64 to 20,784.90 mg.kg-1. With regard to to fatty acid composition, linolenic acid was present in the greatest quantity, and it increase up to 2.58 mg.g-1 (in natura and 40.11 mg.g-1 (dehydrated at 100 days of development. The n-6/n-3 ratios were low in all stages. The TPC and antioxidant activity by DPPH• changed during the developmental stages. The TPC was highest in the 100-day dehydrated leaves (15.27±0.12 mg GAE.g-1 FW, and the 50% inhibition of DPPH• (IC50 89.52 µg.mL-1 were better in the 60-day in natura leaves. This study shows that all developmental stages produced satisfactory results, and therefore, these leaves can be reused as food. The antioxidant activity and the chemical constituents, mainly the ω-3fatty acid, increased during the stages of development.

  2. Analysis of Chemical Composition of Atmospheric Aerosols Above a South East Asian Rainforest

    Science.gov (United States)

    Robinson, N. H.; Allan, J. D.; Williams, P. I.; Hamilton, J. F.; Chen, Q.; Martin, S. T.; Coe, H.; McFiggans, G. B.

    2008-12-01

    The tropics emit a huge amount of volatile organic compounds (VOCs) into the Earth's atmosphere. The processes by which these gases are oxidised to form secondary organic aerosol (SOA) are not well understood or quantified. Insight into the origins and properties of these particles can be gained by analysis of their composition. Intensive field measurements were carried out as part of the Oxidant and Particle Photochemical Processes (OP3) and the Aerosol Coupling in the Earth System (ACES) projects in the rainforest in Malaysian Borneo. This is the first campaign of its type in a South East Asian rainforest. We present detailed organic aerosol composition measurements made using an Aerodyne High Resolution Time of Flight Aerosol Mass Spectrometer (HR-ToF-AMS) at Bukit Atur, a Global Atmosphere Watch site located in the Danum Valley Conservation Area. This is a state-of-the-art field deployable instrument that can provide real time composition, mass loading and aerodynamic particle sizing information. In addition, the mass spectral resolution is sufficient to perform an analysis of the elemental composition of the organic species present. Other tools such as positive matrix factorisation (PMF) have been used to help assess the relative source contributions to the organic aerosol. The aerosol's chemical origins have been further investigated by comparing these spectra to chamber experiments, mass spectral libraries and data from comparable locations in other locations. These data are also being analysed in conjunction with high complexity offline techniques applied to samples collected using filters and a Particle-Into-Liquid Sampler (PILS). Methods used include liquid chromatography and comprehensive two-dimensional gas chromatography coupled to time of flight mass spectrometry. These techniques provide a more detailed chemical characterisation of the SOA and water soluble organic carbon, allowing direct links back to gas phase precursors.

  3. PbO2 based composite materials deposited from suspension electrolytes: electrosynthesis, physico-chemical and electrochemical properties

    OpenAIRE

    Velichenko, Alexander; Knysh, Valentina; Luk’yanenko, Tatiana; Dmitrikova, Larisa; Velichenko, Yulia; Devilliers, Didier

    2012-01-01

    Composite materials based on PbO2 containing TiO2 or ZrO2 were prepared from electrolytes containing a suspension of TiO2 or ZrO2. The contents of foreign oxides in the composite depend on the electrolyte composition and conditions of deposition. When a dispersed phase is incorporated into the composite coating, the dimensions of lead dioxide crystals decrease to submicro- and nano-size. Physico-chemical properties and electrocatalytic activity of composite materials are mainly determin...

  4. The chemical compositions of solar twins in the open cluster M67

    CERN Document Server

    Liu, F; Yong, D; Melendez, J; Ramirez, I; Karakas, A I; Carlos, M; Marino, A F

    2016-01-01

    Stars in open clusters are expected to share an identical abundance pattern. Establishing the level of chemical homogeneity in a given open cluster deserves further study as it is the basis of the concept of chemical tagging to unravel the history of the Milky Way. M67 is particularly interesting given its solar metallicity and age as well as being a dense cluster environment. We conducted a strictly line-by-line differential chemical abundance analysis of two solar twins in M67: M67-1194 and M67-1315. Stellar atmospheric parameters and elemental abundances were obtained with high precision using Keck/HIRES spectra. M67-1194 is essentially identical to the Sun in terms of its stellar parameters. M67-1315 is warmer than M67-1194 by ~ 150 K as well as slightly more metal-poor than M67-1194 by ~ 0.05 dex. M67-1194 is also found to have identical chemical composition to the Sun, confirming its solar twin nature. The abundance ratios [X/Fe] of M67-1315 are similar to the solar abundances for elements with atomic n...

  5. Determining the chemical composition of cloud condensation nuclei. Second progress report

    Energy Technology Data Exchange (ETDEWEB)

    Williams, A.L.; Rothert, J.E.; McClure, K.E. [Illinois State Water Survey, Champaign, IL (United States); Alofs, D.J.; Hagen, D.E.; White, D.R.; Hopkins, A.R.; Trueblood, M.B. [Missouri Univ., Rolla, MO (USA). Cloud and Aerosol Science Lab.

    1992-02-01

    This second progress report describes the status of the project one and one-half years after the start. The goal of the project is to develop the instrumentation to collect cloud condensation nuclei (CCN) in sufficient amounts to determine their chemical composition, and to survey the CCN composition in different climates through a series of field measurements. Our approach to CCN collection is to first form droplets on the nuclei under simulated cloud humidity conditions, which is the only known method of identifying CCN from the background aerosol. Under cloud chamber conditions, the droplets formed become larger than the surrounding aerosol, and can then be removed by inertial impaction. The residue of the evaporated droplets represents the sample to be chemically analyzed. Two size functions of CCN particles are collected by first forming droplets on the large particles are collected by first forming droplets on the large CCN in a haze chamber at 100% relative humidity, and then activating the remaining CCN at 1% supersaturation in a cloud chamber. The experimental apparatus is a serious flow arrangement consisting of an impactor to remove the large aerosol particles, a haze chamber to form droplets on the remaining larger CCN, another impactor to remove the haze droplets containing the larger CCN particles for chemical analysis, a continuous flow diffusion (CFD) cloud chamber to form droplets on the remaining smaller CCN, and a third impactor to remove the droplets for the small CCN sample. Progress is documented here on the development of each of the major components of the flow system. Chemical results are reported on tests to determine suitable wicking material for the different plates. Results of computer modeling of various impactor flows are discussed.

  6. Chemical composition, nutritional value, and antioxidant activities of eight mulberry cultivars from China

    Directory of Open Access Journals (Sweden)

    Linghong Liang

    2012-01-01

    Full Text Available Background: Mulberry (Morus, Moraceae is widely distributed in the temperate, subtropical, or tropical regions of the world, while there are no conclusive reports on the chemical composition, nutritional value, and antioxidant properties of mulberry cultivars from China. Objective: To investigate chemical properties and to determine proximate nutritive compounds of the eight mulberry cultivars. Materials and Methods: Chemical properties (including moisture, ash, total dry matter, total soluble solids, pH, and total titratable acidity of the eight mulberry cultivars were investigated. Proximate nutritive compounds (including crude protein, crude fat, mineral elements, total anthocyanins, total polyphenols, total flavonoids, and total sugars were also determined. Results: The results indicated that the moisture contents were 70.0-87.4%, the crude protein contents 1.62-5.54%, and the crude fat contents from 1.23-2.23%. The major fatty acids in mulberry fruits were linoleic acid (C 18:2 and palmitic acid (C 16:0 , 26.40-74.77% and 9.29-22.26%, respectively. Mulberry fruit is also a good source of minerals and the potassium content (521.37-1718.60 mg/100g DW is especially higher than that of other elements. Compared with other species, the Morus atropurpurea Roxb. had relatively high total polyphenols content (189.67-246.00 mg GAE/100mg and anthocyanins content (114.67-193.00 mg/100mg. There was a good linear correlation between antioxidant activity and total polyphenols content. Conclusion: Significant differences of the chemical composition, nutritional value, and antioxidant activities among the mulberry cultivars were observed, the Morus atropurpurea Roxb. showed considerable high nutritional value and antioxidant activity which could be developed for functional food that benefits human health.

  7. Plant Species Rather Than Climate Greatly Alters the Temporal Pattern of Litter Chemical Composition During Long-Term Decomposition

    Science.gov (United States)

    Li, Yongfu; Chen, Na; Harmon, Mark E.; Li, Yuan; Cao, Xiaoyan; Chappell, Mark A.; Mao, Jingdong

    2015-10-01

    A feedback between decomposition and litter chemical composition occurs with decomposition altering composition that in turn influences the decomposition rate. Elucidating the temporal pattern of chemical composition is vital to understand this feedback, but the effects of plant species and climate on chemical changes remain poorly understood, especially over multiple years. In a 10-year decomposition experiment with litter of four species (Acer saccharum, Drypetes glauca, Pinus resinosa, and Thuja plicata) from four sites that range from the arctic to tropics, we determined the abundance of 11 litter chemical constituents that were grouped into waxes, carbohydrates, lignin/tannins, and proteins/peptides using advanced 13C solid-state NMR techniques. Decomposition generally led to an enrichment of waxes and a depletion of carbohydrates, whereas the changes of other chemical constituents were inconsistent. Inconsistent convergence in chemical compositions during decomposition was observed among different litter species across a range of site conditions, whereas one litter species converged under different climate conditions. Our data clearly demonstrate that plant species rather than climate greatly alters the temporal pattern of litter chemical composition, suggesting the decomposition-chemistry feedback varies among different plant species.

  8. CHEMICAL COMPOSITION AND PCT DATA FOR THE INITIAL SET OF HANFORD ENHANCED WASTE LOADING GLASSES

    Energy Technology Data Exchange (ETDEWEB)

    Fox, K.; Edwards, T.

    2014-06-02

    In this report, the Savannah River National Laboratory provides chemical analyses and Product Consistency Test results for 20 simulated high level waste glasses fabricated by the Pacific Northwest National Laboratory. The results of these analyses will be used as part of efforts to revise or extend the validation ranges of the current Hanford Waste Treatment and Immobilization Plant glass property models to cover a broader span of waste compositions. The measured chemical composition data are reported and compared with the targeted values for each component for each glass. Two components of the study glasses, fluorine and silver, were not measured since each of these species would have required the use of an additional preparation method and their measured values were likely to be near or below analytical detection limits. Some of the glasses were difficult to prepare for chemical analysis. A sodium peroxide fusion dissolution method was successful in completely dissolving the glasses. Components present in the glasses in minor concentrations can be difficult to measure using this dissolution method due to dilution requirements. The use of a lithium metaborate preparation method for the minor components (planned for use since it is typically successful in digesting Defense Waste Processing Facility HLW glasses) resulted in an unacceptable amount of undissolved solids remaining in the sample solutions. An acid dissolution method was used instead, which provided more thorough dissolution of the glasses, although a small amount of undissolved material remained for some of the study glasses. The undissolved material was analyzed to determine those components of the glasses that did not fully dissolve. These components (e.g., calcium and chromium) were present in sufficient quantities to be reported from the measurements resulting from the sodium peroxide fusion preparation method, which did not leave undissolved material. Overall, the analyses resulted in sums of

  9. Thermodynamic Modeling of the Chemical Composition of Calcine at the Idaho Nuclear Technology and Engineering Center

    International Nuclear Information System (INIS)

    To send calcine produced at Idaho National Engineering and Environmental Laboratory to the Yucca Mountain Project for disposal, characterization information will be required. To sample calcine from its existing storage location would require extensive personnel exposure. Sufficient analyses of the chemical composition of the calcine would be extremely difficult and very expensive. In support of characterization development, the chemical composition of calcine from Bin 3 of Calcine Solid Storage Facility II was thermodynamic modeled. This calcine was produced in the Waste Calcination Facility during its second processing campaign, operating with indirect heating at 400 C and 0.744 bar (0.734 atm) during processing of aluminum high-level liquid waste (first cycle extraction raffinate from reprocessing aluminum-clad fuels) from tanks WM-180 and -182 from December 27, 1966 through August 26, 1967. The current modeling effort documents the input compositional data (liquid feed and calciner off-gas) for Batches 300 - 620 and a methodology for estimating the calcine chemical composition. The results, along with assumptions and limitations of the thermodynamic calculations, will serve as a basis for benchmarking subsequent calculations. This will be done by comparing the predictions against extensive analytical results that are currently being obtained on representative samples of the modeled calcine. A commercial free-energy minimization program and database, HSC 5.1, was used to perform the thermodynamic calculations. Currently available experimental data and process information on the calcine were used to make judgments about specific phases and compounds to include and eliminate in the thermodynamic calculations. Some off-gas species were eliminated based on kinetics restrictions evidenced by experimental data and other estimates, and some calcine components and off-gas compounds were eliminated as improbable species (unreliable thermodynamic data). The current Yucca

  10. Seasonal Variation, Chemical Composition and Antioxidant Activity of Brazilian Propolis Samples

    Directory of Open Access Journals (Sweden)

    Érica Weinstein Teixeira

    2010-01-01

    Full Text Available Total phenolic contents, antioxidant activity and chemical composition of propolis samples from three localities of Minas Gerais state (southeast Brazil were determined. Total phenolic contents were determined by the Folin–Ciocalteau method, antioxidant activity was evaluated by DPPH, using BHT as reference, and chemical composition was analyzed by GC/MS. Propolis from Itapecerica and Paula Cândido municipalities were found to have high phenolic contents and pronounced antioxidant activity. From these extracts, 40 substances were identified, among them were simple phenylpropanoids, prenylated phenylpropanoids, sesqui- and diterpenoids. Quantitatively, the main constituent of both samples was allyl-3-prenylcinnamic acid. A sample from Virginópolis municipality had no detectable phenolic substances and contained mainly triterpenoids, the main constituents being α- and β-amyrins. Methanolic extracts from Itapecerica and Paula Cândido exhibited pronounced scavenging activity towards DPPH, indistinguishable from BHT activity. However, extracts from Virginópolis sample exhibited no antioxidant activity. Total phenolic substances, GC/MS analyses and antioxidant activity of samples from Itapecerica collected monthly over a period of 1 year revealed considerable variation. No correlation was observed between antioxidant activity and either total phenolic contents or contents of artepillin C and other phenolic substances, as assayed by CG/MS analysis.

  11. Chemical composition analysis, antioxidant and antibacterial activity evaluation of essential oil of Atalantia monophylla Correa

    Directory of Open Access Journals (Sweden)

    Ramaraj Thirugnanasampandan

    2015-01-01

    Full Text Available Background: Atalantia monophylla Correa. a small tree belongs to the family Rutaceae. It is distributed throughout India and in Tamil Nadu the species is commonly seen in foothills of dry vegetation. Objective: The aim was to hydrodistillate and analyze the chemical composition of essential oil from the fresh leaves of A. monophylla Correa. collected in two different seasons (December, 2013 and May, 2014 and to evaluate antioxidant and antibacterial activities of isolated essential oil. Materials and Methods: Chemical composition of isolated essential oil was analyzed by gas chromatography, gas chromatography coupled with mass spectrometry. Antioxidant activity of oil was assessed using five different antioxidant test systems. Antibacterial activity of oil was tested against six pathogenic bacteria by broth dilution method. Results: Essential oil obtained from the leaves collected during May, 2014 had shown more compounds. Antioxidant activity of oil was moderate when compared with positive control. Minimum inhibitory concentration value of oil was ranges between 139.32 ± 0.001 and 541.11 ± 0.003 µg/mL against all the tested bacteria. Conclusion: Result clearly indicates essential oil collected during May, 2014 showed more bioactive compounds.

  12. Effect of chemical composition and density of the pelvic structure in intracavitary brachytherapy dosimetry

    International Nuclear Information System (INIS)

    High dose rate (HDR) and low dose rate (LDR) intracavitary brachytherapies dosimetry in clinical practice are typically performed by commercial treatment planning systems. However, these systems do not fully consider the heterogeneities present in the real structure of the patient. The aim of this work is to obtain isodose curves and surfaces around the usual array of sources used in LDR (137Cs) and HDR (192Ir) intracavitary brachytherapy by Monte Carlo simulation, considering the real anatomic structure, density and chemical composition of media and tissues from the female pelvic region. The structural information was obtained from computed tomography images in the DICOM format. A voxel phantom (VP) was developed to perform ionizing radiation transport, considering the gamma spectrum of 137Cs and 192Ir. The absorbed dose was computed within each voxel of 2x2x3 mm3. Four materials were considered in the VP-air, fat, muscle tissue and bone; however, one material per voxel was defined. Results show and quantify the effect of density and chemical composition of the medium on the absorbed dose distribution. According to them, the treatment planning systems underestimate the absorbed dose by 8% approximately for both radionuclides. In a heterogeneous medium, the absorbed dose distribution of 192Ir is more irregular than that of 137Cs but spatially better defined.

  13. High temperature chemical compatibility between SiC composites and Be pebbles

    International Nuclear Information System (INIS)

    SiC composite reinforced fibres are still considered to be an important material to be used in nuclear fusion reactors due to their high temperature and low neutron activation properties. Two different kinds of SiC/SiCf composite were manufactured, one of them presenting an extra SiC coating obtained by chemical vapour deposition technique. Several samples of both materials were placed inside a Be pebble bed and the whole set-up annealed at 800 deg. C for 550 h in a reducing atmosphere, simulating fusion reactor conditions. Surface chemical reactions were investigated with nuclear microprobe analyses techniques and complemented with SEM analysis. For the uncoated samples, surface oxidation is accompanied by a strong C depletion and a Be diffusion. Two different behaviours were found for the coated samples. One of those samples showed extended regions where surface was left almost unaltered. The general behaviour, however, was an increase in the number and extension of the cracks already observed at the surface of the coated virgin samples

  14. Chemical composition of leaf extracts of Stevia rebaudiana Bertoni grown experimentally in Vojvodina

    Directory of Open Access Journals (Sweden)

    IVANA S. MARKOVIC

    2008-03-01

    Full Text Available The chemical composition of leaf extracts of Stevia rebaudiana Bertoni, grown for the first time on an experimental field near Zrenjanin, was examined by GC–MS. The tested plant material was harvested in September of 2002. To analyze the chemical composition of the lipophilic components of the plant leaves, essential oils and ethyl acetate extract were isolated. Qualitative analysis of the essential oil obtained by hydrodistillation showed that among the identified 88 compounds, the majority were mono- and sesquiterpenes (50 types identified. By analysing the ethyl acetate extract, the presence of fatty acids (present as free and as esters, n-alkanes, n-alkenes, cyclic alkanes, alcohols, aldehydes, ketones, etc. was ascertained. Sesquiterpenes prevailed among the terpenes (50 types identified. Further constituents identified in ethyl acetate extract included sterols. Nerol, b-cyclocitral, safranal, aromadendrene, a-amorphene and T-muurolol were identified for the first time in this species, with match values over 90 %. Taking into consideration that these terpenes were identified for the first time in this species, it is obvious that Stevia rebaudiana grown in this area possesses certain specific characteristics that can be ascribed to cultivation on a domestic plantation.

  15. Contact Toxicity and Chemical Composition of Essential Oil of Acantholimon scorpius

    Directory of Open Access Journals (Sweden)

    Ardalan Pasdaran Lashgari, Abbas Delazar, Farriba Hesmati Afshar, Dena Parsa

    2016-06-01

    Full Text Available Background: Plumbaginaceae plants family is a valuable natural insecticidal compound. This research focused on contact toxicity and chemical composition of essential oil obtained from Acantholimon scorpus. Methods: The essential oil from the aerial parts of A. scorpius was extracted by hydrodistillation method and tested for their toxicity against Oryzeaphilus mercator (Coleoptera: Silvanidae and Tribolium castaneum (Coleoptera: Tenerbrionidae. Chemical compounds of the essential oil was analyzed by the gas chromatography-mass spectrometry (GC-MS and gas chromatography-flame ionization detection (GC-FID. Results: The essential oil showed toxic effect on tested insects. This oil showed 90.0% mortality of O. mercator and 85.2% mortality of T. castaneum at a dose of 12 μl /l air after 48h of exposure. The constituents of this oil were identified, representing more than 82.9% of the total essential oil composition. Hexadecanoic acid, tetrahydrogeranyl acetone and oleic acid were the main compounds of the essential oil. Conclusion: According to the result the essential oil of A. scorpius showed a noticeable insecticidal activity in contact toxicity model.

  16. Chemical composition of Nigella sativa L. seed extracts obtained by supercritical carbon dioxide.

    Science.gov (United States)

    Tiruppur Venkatachallam, Suresh Kumar; Pattekhan, Hajimalang; Divakar, Soundar; Kadimi, Udaya Sankar

    2010-12-01

    Chemical composition of black cumin (Nigella sativa L.) seed extracts obtained by supercritical carbon dioxide at two different conditions that result in total extract (28 MPa/50°C, SFE 1) and major volatile part (12 MPa/40°C, SFE 2) and essential oil obtained by hydrodistillation of SFE-1 (HD SFE). SFE have been carried out to characterize the compounds and the variation of quinones and phenolics. The extracts were analysed by GC and GC-MS and the presence of phenolic compounds was further confirmed by 2D HSQCT (1)H and (13)C NMR spectroscopy. Forty-seven volatile compounds were detected where sixteen compounds were reported for the first time in the oil of this seed. Moreover, thymoquinone (TQ), dithymoquinone (DTQ), thymohydroquinone (THQ) and thymol (THY) were the major phenolic compounds. It can be concluded that the chemical composition of extracts obtained by SC CO2 extraction of the seeds showed better recovery of phenolic compounds than HD SFE and proved the occurrence of thermally labile or photosensitive bioactive volatiles of four major quinonic phenol compounds. PMID:23572692

  17. Chemical composition and starch digestibility in flours from Polish processed legume seeds.

    Science.gov (United States)

    Piecyk, Małgorzata; Wołosiak, Rafał; Drużynska, Beata; Worobiej, Elwira

    2012-12-01

    The study was undertaken to determine the effect of various treatments, i.e. cooking after soaking, freezing after cooking and storage at a low temperature (-18°C, 21days), and autoclaving, of Polish cultivars of bean, pea and lentil seeds on the chemical composition and starch digestibility of the resultant flours. The cooking of seeds caused a significant decrease in contents of ash (by 11-48%), polyphenols (by 10-70%) and protein (to 19%) in flours made of bean. In addition, analyses demonstrated significantly decreased contents of resistant starch, RS (by 61-71%) and slowly digestible starch, SDS (by 56-84%). Storage of frozen seeds resulted in insignificant changes in the chemical composition, and in increased contents of both RS and SDS. The flours produced upon the autoclaving process were characterized by similar changes in the contents of ash and protein as in cooked seeds, yet losses of polyphenols were lower and, simultaneously, contents of RS and SDS were higher. All the analyzed flours were shown to be characterized by a reduced content of amylose in starch, which might have affected its digestibility. This was indicated by a strict negative correlation reported between the value of the starch digestion index (SDRI) and amylose content of starch (r=0.84, p>0.05). PMID:22953824

  18. Superconducting properties and chemical composition of NbTiN thin films with different thickness

    International Nuclear Information System (INIS)

    In this research, we systematically investigated the superconducting properties and chemical composition of NbTiN thin films prepared on single-crystal MgO substrates. The NbTiN thin films with different thicknesses (4–100 nm) were deposited by reactive DC magnetron sputtering at ambient temperature. We measured and analyzed the crystal structure and thickness dependence of the chemical composition using X-ray diffraction and X-ray photoelectron spectroscopy depth profiles. The films exhibited excellent superconducting properties, with a high superconducting critical temperature of 10.1 K, low resistivity (ρ20 = 93 μΩ cm), and residual resistivity ratio of 1.12 achieved for 4-nm-thick ultrathin NbTiN films prepared at the deposition current of 2.4 A. The stoichiometry and electrical properties of the films varied gradually between the initial and upper layers. A minimum ρ20 of 78 μΩ cm and a maximum residual resistivity ratio of 1.15 were observed for 12-nm-thick films, which significantly differ from the properties of NbN films with the same NaCl structure

  19. The influence of chemical composition on structure and mechanical properties of austenitic Cr-Ni steels

    Directory of Open Access Journals (Sweden)

    A. Kurc-Lisiecka

    2013-12-01

    Full Text Available Purpose: The aim of the paper is to investigated the influence of the chemical composition on the structure and mechanical properties of austenitic Cr-Ni steels. Special attention was put on the effect of solution heat treatment on mechanical properties of examined steels. Design/methodology/approach: The examinations of static tensile tests were conducted on ZWICK 100N5A. Hardness measurements were made by Vickers method. The X-ray analyzes were realized with the use of Dron 2.0 diffractometer equipped with the lamp of the cobalt anode. The metallographic observations were carried out on LEICA MEF 4A light microscope. Findings: Results shown that after solution heat treatment the values of strength properties (UTS, YS0.2 and hardness (HV of both investigated steels decrease and their elongation (EL increases. The X5CrNi18-8 steel in delivery state shown austenitic microstructure with twins and numerous non-metallic inclusions, while in steel X10CrNi18-8 revealed a austenitic microstructure with numerous slip bands in areas with deformation martensite α’. The examined steels after solution heat treatment followed by water-cooling has the structure of austenite. Research limitations/implications: To investigate in more detail the influence of chemical composition on structure and mechanical properties the examinations of substructure by TEM should be conducted. Originality/value: The relationship between the solution heat treatment, structure and mechanical properties of investigated steels was specified.

  20. Histochemistry, content and chemical composition of essential oil in different organs of Alpinia zerumbet

    Directory of Open Access Journals (Sweden)

    Caroline Nery Jezler

    2013-10-01

    Full Text Available Alpinia zerumbet is a medicinal plant from Asian origin used in folk medicine for the treatment of hypertension, which effect is attributed to terpinen-4-ol, the major component of the essential oil. The objective of this work was to identify the essential oil secretory structures in the leaf, flower, root and rhizome of this plant, and analyze the content and the chemical composition of the oil in the different organs of the plant. Sections were subjected to histochemical test with Nadi reagent for in situ localization of secretion. The essential oil extraction was performed by hydrodistillation in a Clevenger apparatus and the compounds were identified in CG-EM/FID. The histochemical test was positive for terpenoids, confirming the presence of essential oil stored in secretory structures named oils cells present in all analyzed organs. The higher essential oil content was found on the leaf (0.30%, while the petal and the rhizome presented content of 0.10% and 0.06%, respectively. It was not possible to determine essential oil content of the root due to the low amount of biomass produced. There were qualitative and quantitative differences in the chemical composition of the essential oil in the different plant organs, but the major constituent in all of them was the terpinen-4-ol, followed by 1,8 cineol in the leaf and by the α-terpineol in the flower and rhizome.

  1. The influence of chemical composition on the properties and structure Al-Si-Cu(Mg alloys

    Directory of Open Access Journals (Sweden)

    M. Kaczorowski

    2007-04-01

    Full Text Available The mechanical properties of different chemical composition AlSiCuMg type cast alloys after precipitation hardening are presented. The aim of the study was to find out how much the changes in chemistry of aluminum cast alloys permissible by EN-PN standards may influence the mechanical properties of these alloys. Eight AlSi5Cu3(Mg type cast alloys of different content alloying elements were selected for the study. The specimens cut form test castings were subjected to precipitation hardening heat treatment. The age hardened specimens were evaluated using tensile test, hardness measurements and impact test. Moreover, the structure investigation were carried out using either conventional light Metallography and scanning (SEM and transmission (TEM electron microscopy. The two last methods were used for fractography observations and precipitation process observations respectively. It was concluded that the changes in chemical composition which can reach even 2,5wt.% cause essential differences of the structure and mechanical properties of the alloys. As followed from quantitative evaluation and as could be predicted theoretically, copper and silicon mostly influenced the mechanical properties of AlSi5Cu3(Mg type cast alloys. Moreover it was showed that the total concentration of alloying elements accelerated and intensifies the process of decomposition of supersaturated solid solution. The increase of Cu and Mg concentration increased the density of precipitates. It increases of strength properties of the alloys which are accompanied with decreasing in ductility.

  2. Predicting coal ash fusion temperature based on its chemical composition using ACO-BP neural network

    International Nuclear Information System (INIS)

    Coal ash fusion temperature is important to boiler designers and operators of power plants. Fusion temperature is determined by the chemical composition of coal ash, however, their relationships are not precisely known. A novel neural network, ACO-BP neural network, is used to model coal ash fusion temperature based on its chemical composition. Ant colony optimization (ACO) is an ecological system algorithm, which draws its inspiration from the foraging behavior of real ants. A three-layer network is designed with 10 hidden nodes. The oxide contents consist of the inputs of the network and the fusion temperature is the output. Data on 80 typical Chinese coal ash samples were used for training and testing. Results show that ACO-BP neural network can obtain better performance compared with empirical formulas and BP neural network. The well-trained neural network can be used as a useful tool to predict coal ash fusion temperature according to the oxide contents of the coal ash

  3. On the binary helium star DY Centauri: Chemical composition and evolutionary state

    CERN Document Server

    Pandey, Gajendra; Jeffery, C Simon; Lambert, David L

    2014-01-01

    DY Cen has shown a steady fading of its visual light by about 1 magnitude in the last 40 years suggesting a secular increase in its effective temperature. We have conducted non-LTE and LTE abundance analyses to determine the star's effective temperature, surface gravity, and chemical composition using high-resolution spectra obtained over two decades. The derived stellar parameters for three epochs suggest that DY Cen has evolved at a constant luminosity and has become hotter by about 5000 K in 23 years. We show that the derived abundances remain unchanged for the three epochs. The derived abundances of the key elements, including F and Ne, are as observed for the extreme helium stars resulting from a merger of an He white dwarf with a C-O white dwarf. Thus, DY Cen by chemical composition appears to be also a product of a merger of two white dwarfs. This appearance seems to be at odds with the recent suggestion that DY Cen is a single-lined spectroscopic binary.

  4. Larvicidal efficacies and chemical composition of essential oils of Pinus sylvestris and Syzygium aromaticum against mosquitoes

    Institute of Scientific and Technical Information of China (English)

    Kehinde Adenike Fayemiwo; Monsuru Adebayo Adeleke; Ovie Princewill Okoro; Shola Hezekiah Awojide; Ilias Olufemi Awoniyi

    2014-01-01

    Objective:To assess the chemical composition and mosquito larvicidal potentials of essential oils of locally sourced Pinus sylvestris (P. sylvestris) and Syzygium aromaticum (S. aromaticum) against Aedes aegypti (A. aegypti) and Culex quinquefasciatus (C. quinquefasciatus). Method:The chemical composition of the essential oils of both plants was determined using GC-MS while the larvicidal bioassay was carried out using different concentrations of the oils against the larvae of A. aegypti and C. quinquefasciatus in accordance with the standard protocol. Results:The results as determined by GC-MS showed that oil of S. aromaticum has eugenol (80.5%) as its principal constituent while P. sylvestris has 3-Cyclohexene-1-methanol, .alpha., .alpha.4-trimethyl (27.1%) as its dominant constituent. Both oils achieved over 85%larval mortality within 24 h. The larvae of A. aegypti were more susceptible to the oils [LC50 (S. aromaticum)=92.56 mg/L, LC50(P. sylvestris)=100.39 mg/L] than C. quinquefasciatus [LC50(S. aromaticum)=124.42 mg/L;LC50(P. sylvestris)=128.00 mg/L]. S. aromaticum oil was more toxic to the mosquito larvae than oil of P. sylvestris but the difference in lethal concentrations was insignificant (P>0.05). Conclusion: The results justify the larvicidal potentials of both essential oils and the need to incorporate them in vector management and control.

  5. Superconducting properties and chemical composition of NbTiN thin films with different thickness

    Energy Technology Data Exchange (ETDEWEB)

    Zhang, L.; Peng, W.; You, L. X.; Wang, Z., E-mail: zwang@mail.sim.ac.cn [State Key Laboratory of Functional Materials for Informatics, Shanghai Institute of Microsystem and Information Technology (SIMIT), Chinese Academy of Sciences (CAS), Shanghai 200050 (China)

    2015-09-21

    In this research, we systematically investigated the superconducting properties and chemical composition of NbTiN thin films prepared on single-crystal MgO substrates. The NbTiN thin films with different thicknesses (4–100 nm) were deposited by reactive DC magnetron sputtering at ambient temperature. We measured and analyzed the crystal structure and thickness dependence of the chemical composition using X-ray diffraction and X-ray photoelectron spectroscopy depth profiles. The films exhibited excellent superconducting properties, with a high superconducting critical temperature of 10.1 K, low resistivity (ρ{sub 20} = 93 μΩ cm), and residual resistivity ratio of 1.12 achieved for 4-nm-thick ultrathin NbTiN films prepared at the deposition current of 2.4 A. The stoichiometry and electrical properties of the films varied gradually between the initial and upper layers. A minimum ρ{sub 20} of 78 μΩ cm and a maximum residual resistivity ratio of 1.15 were observed for 12-nm-thick films, which significantly differ from the properties of NbN films with the same NaCl structure.

  6. Processes controlling the chemical composition of natural waters in the Hreppar-Land in Southern Iceland

    International Nuclear Information System (INIS)

    This contribution describes the processes controlling the chemical and isotopic composition of cold and geothermal waters (5-150 deg. C) in the Hreppar-Land area in southern Iceland. The chemical composition of surface-and cold groundwaters are controlled by the salt content of the precipitation, rock dissolution and organic CO2 from the soil. The dissolved solids content of the geothermal waters is higher than that of the cold waters and it increases with temperature. The cause is increased rock dissolution. Chloride and boron are considered to act as essentially mobile elements in the Icelandic surface- and ground water environment. The Cl-B relationships in the waters are considered to reflect that the geothermal water represents local precipitation. Yet, the δ 2H values of these waters tend to be lower than that of local waters. This difference is not considered to reflect a distant recharge areas to the geothermal systems on higher ground inland but due to the presence of a small component of ''ice-age water'' in the geothermal water that entered the bedrock during the deglaciation period, even earlier, when the δ 2H of meteoric water in Iceland was much lower than that of today's precipitation. 26 refs, 11 figs, 3 tabs

  7. Chemical composition and antimicrobial activity of the essential oil from leaves of Algerian Melissa officinalis L.

    Science.gov (United States)

    Abdellatif, Fahima; Boudjella, Hadjira; Zitouni, Abdelghani; Hassani, Aicha

    2014-01-01

    The essential oil obtained from leaves of Melissa officinalis L. (Family of Lamiaceae) growing in Algeria, was investigated for its chemical composition and in vitro antimicrobial activity. The chemical composition was determined by hydrodistillation and analyzed by GC/MS and GC-FID. Sixty-three compounds were identified in the essential oil, representing 94.10 % of the total oil and the yields were 0.34 %. The major component was geranial (44.20 %). Other predominant components were neral (30.20 %) and citronellal (6.30 %). The in vitro antimicrobial activity was determined by paper disk agar diffusion testing and minimum inhibitory concentration (MIC) using 7 bacteria (3 Gram-positive and 4 Gram-negative), 2 yeasts and 3 fungi. The results showed that the essential oil presented high antimicrobial activity against all microorganisms targeted mainly against five human pathogenic bacteria, one yeast Candida albicans and two phytopathogenic fungi tested. The minimum inhibitory concentrations (MIC) ranged from 1.00 to 5.00 µL/mL. PMID:26417300

  8. Mineral and chemical composition of the Jezersko meteorite—A new chondrite from Slovenia

    Science.gov (United States)

    Miler, Miloš; Ambrožič, Bojan; Mirtič, Breda; Gosar, Mateja; Å turm, Sašo.; Dolenec, Matej; Jeršek, Miha

    2014-10-01

    The Jezersko meteorite is a newly confirmed stony meteorite found in 1992 in the Karavanke mountains, Slovenia. The meteorite is moderately weathered (W2), indicating short terrestrial residence time. Chondrules in partially recrystallized matrix are clearly discernible but often fragmented and have mean diameter of 0.73 mm. The meteorite consists of homogeneous olivine (Fa19.4) and low-Ca pyroxenes (Fs16.7Wo1.2), of which 34% are monoclinic, and minor plagioclase (Ab83An11Or6) and Ca-pyroxene (Fs6Wo45.8). Troilite, kamacite, zoned taenite, tetrataenite, chromite, and metallic copper comprise about 16.5 vol% of the meteorite. Phosphates are represented by merrillite and minor chlorapatite. Undulatory extinction in some olivine grains and other shock indicators suggests weak shock metamorphism between stages S2 and S3. The bulk chemical composition generally corresponds to the mean H chondrite composition. Low siderophile element contents indicate the oxidized character of the Jezersko parent body. The temperatures recorded by two-pyroxene, olivine-chromite, and olivine-orthopyroxene geothermometers are 854 °C, 737-787 °C, and 750 °C, respectively. Mg concentration profiles across orthopyroxenes and clinopyroxenes indicate relatively fast cooling at temperatures above 700 °C. A low cooling rate of 10 °C Myr-1 was obtained from metallographic data. Considering physical, chemical, and mineralogical properties, meteorite Jezersko was classified as an H4 S2(3) ordinary chondrite.

  9. Chemical Composition, Antimicrobial and Antioxidant Activities of the Volatile Oil of Ganoderma pfeifferi Bres

    Directory of Open Access Journals (Sweden)

    Mohamed Al-Fatimi

    2016-04-01

    Full Text Available In a first study of the volatile oil of the mushroom basidiomycete Ganoderma pfeifferi Bres., the chemical composition and antimicrobial and antioxidant activities of the oil were investigated. The volatile oil was obtained from the fresh fruiting bodies of Ganoderma pfeifferi Bres. By hydrodistillation extraction and analyzed by GC-MS. The antimicrobial activity of the oil was evaluated against five bacteria strains and two types of fungi strains, using disc diffusion and broth microdilution methods. In addition, the antioxidant activity of the oil was determined using DPPH assay. Four volatile compounds representing 90.5% of the total oil were identified. The majority of the essential oil was dominated by 1-octen-3-ol (amyl vinyl carbinol 1 (73.6% followed by 1-octen-3-ol acetate 2 (12.4%, phenylacetaldehyde 3 (3.0% and 6-camphenol 4 (1.5%. The results showed that the Gram-positive bacteria species are more sensitive to the essential oil than Gram-negative bacteria. The oil showed strong antimicrobial activity against Staphylococcus aureus as well as Candida albicans. Moreover, the oil exhibited strong radical scavenging activity in the DPPH assay. This first report on the chemical composition and biological properties of G. pfeifferi volatile oil makes its pharmaceutical uses rational and provides a basis in the biological and phytochemical investigations of the volatile oils of Ganodermataceae species.

  10. Effect of chemical composition and density of the pelvic structure in intracavitary brachytherapy dosimetry

    Energy Technology Data Exchange (ETDEWEB)

    Chavez-Aguilera, N. [Coordinacion de Investigacion y Estudios de Posgrado, Facultad de Medicina, Universidad Autonoma del Estado de Mexico, Paseo Tollocan s/n Esquina con Jesus Carranza, 50180 Toluca (Mexico); Departamento de Fisica Medica, Instituto Estatal de Cancerologia ' Dr. Arturo Beltran Ortega' , Acapulco, Guerrero (Mexico); Torres-Garcia, E., E-mail: etorresg@uaemex.m [Coordinacion de Investigacion y Estudios de Posgrado, Facultad de Medicina, Universidad Autonoma del Estado de Mexico, Paseo Tollocan s/n Esquina con Jesus Carranza, 50180 Toluca (Mexico); Mitsoura, E. [Coordinacion de Investigacion y Estudios de Posgrado, Facultad de Medicina, Universidad Autonoma del Estado de Mexico, Paseo Tollocan s/n Esquina con Jesus Carranza, 50180 Toluca (Mexico)

    2011-03-15

    High dose rate (HDR) and low dose rate (LDR) intracavitary brachytherapies dosimetry in clinical practice are typically performed by commercial treatment planning systems. However, these systems do not fully consider the heterogeneities present in the real structure of the patient. The aim of this work is to obtain isodose curves and surfaces around the usual array of sources used in LDR ({sup 137}Cs) and HDR ({sup 192}Ir) intracavitary brachytherapy by Monte Carlo simulation, considering the real anatomic structure, density and chemical composition of media and tissues from the female pelvic region. The structural information was obtained from computed tomography images in the DICOM format. A voxel phantom (VP) was developed to perform ionizing radiation transport, considering the gamma spectrum of {sup 137}Cs and {sup 192}Ir. The absorbed dose was computed within each voxel of 2x2x3 mm{sup 3}. Four materials were considered in the VP-air, fat, muscle tissue and bone; however, one material per voxel was defined. Results show and quantify the effect of density and chemical composition of the medium on the absorbed dose distribution. According to them, the treatment planning systems underestimate the absorbed dose by 8% approximately for both radionuclides. In a heterogeneous medium, the absorbed dose distribution of {sup 192}Ir is more irregular than that of {sup 137}Cs but spatially better defined.

  11. Influence of chemical composition of precipitation on migration of radioactive caesium in natural soils

    International Nuclear Information System (INIS)

    The aim of the present work was to study the impact of the chemical composition of precipitation on radiocaesium mobility in natural soil. This was done through column studies. Three types of precipitation regimes were studied, representing a natural range found in Norway: Acidic precipitation (southernmost part of the country); precipitation rich in marine cations (highly oceanic coastal areas); and low concentrations of sea salts (slightly continental inland areas). After 50 weeks and a total precipitation supply of ∼10 000 L m−2 per column, results indicate that acidic precipitation increased the mobility of 134Cs added during the experiment. However, depth distribution of already present Chernobyl fallout 137Cs was not significantly affected by the chemical composition of precipitation. - Highlights: • Mobility of freshly added Cs-134 was higher in soil receiving acidic precipitation. • Depth penetration of Cs-134 was higher in soil profiles with a thicker humus layer. • Depth distribution of Chernobyl Cs-137 was not affected by precipitation type

  12. The influence of chemical composition of commercial lemon essential oils on the growth of Candida strains.

    Science.gov (United States)

    Białoń, M; Krzyśko-Łupicka, T; Koszałkowska, M; Wieczorek, P P

    2014-02-01

    Candida yeasts are saprophytes naturally present in the environment and forming colonies on human mucous membranes and skin. They are opportunistic fungi that cause severe and even fatal infections in immunocompromised individuals. Several essential oils, including eucalyptus, pine, cinnamon and lemon, have been shown to be effective against Candida strains. This study addresses the chemical composition of some commercial lemon essential oils and their antifungal potential against selected Candida yeast strains. Antifungal potential and minimum inhibitory concentrations were determined for six commercial lemon essential oils against five Candida yeast strains (Candida albicans 31, Candida tropicalis 32, Candida glabrata 33, Candida glabrata 35 and Candida glabrata 38). On the basis of the GCMS analysis, it was found that the tested lemon essential oils had different chemical compositions, but mostly, they contained almost exclusively terpenes and oxygenated terpenes. The tests show that antifungal potential of lemon essential oils against Candida yeast strains was related to the high content of monoterpenoids and the type of Candida strains. From six tested commercial oils, only four (ETJA, Vera-Nord, Avicenna-Oil and Aromatic Art) shows antifungal potential against three Candida species (C. albicans, C. tropicalis and C. glabrata). Vera-Nord and Avicenna-Oil show the best activity and effectively inhibit the growth of the C. albicans strain across the full range of the concentrations used. Our study characterises lemon essential oils, which could be used as very effective natural remedies against candidiasis caused by C. albicans. PMID:24436010

  13. Influence of chemical composition on microstructure and strength of alloy 718

    Energy Technology Data Exchange (ETDEWEB)

    Fedorova, T.; Roesler, J.; Gehrmann, B. [Technische Univ. Braunschweig (Germany); Kloewer, J. [ThyssenKrupp VDM GmbH, Werdohl (Germany)

    2010-07-01

    Alloy 718 has been used for many years due to its unique mechanical properties and good processing characteristics. However, the temperature limit for Alloy 718 is about 650 C because of the thermal instability of the main strengthening phase {gamma}''-Ni{sub 3}(Nb, Ti, Al). At high temperatures meta-stable {gamma}'' changes into stable {delta}-Ni{sub 3}Nb with large size and plate-like morphology. As a consequence of this the alloy looses its microstructural stability and strength. The basic intent of this paper is to examine the role of major and minor elements within typical specification limits for Alloy 718 with respect to (i) microstructure evolution, (ii) strengthening effects and (iii) thermal stability of {gamma}' and {gamma}''. For this purpose, thermodynamic calculations using the software THERMOCALC were performed, varying the content of Nb, Ti, Al as well as B and Zr. In addition, alloys with precisely controlled chemical composition were prepared by drop casting in a vacuum arc furnace and hot forged, so that it was possible to compare the theoretical predictions with experimental results. The microstructure evolution was studied in detail by means of scanning electron microscopy and X-ray diffraction. Furthermore, mechanical properties including tensile and creep behaviour were examined. Based on these results, dependencies between chemical composition and microstructural stability will be elucidated. (orig.)

  14. Evolution of mechanical properties of silicate glasses: Impact of the chemical composition and effects of irradiation

    International Nuclear Information System (INIS)

    This thesis examines: (1) how the chemical composition changes the hardness, toughness, and stress corrosion cracking behavior in model pristine and (2) how external irradiation impact these properties. It is to be incorporated in the context of the storage of nuclear waste in borosilicate glass matrix, the structural integrity of which should be assessed. Eight simplified borosilicate glasses made of 3 oxides with modulated proportions (SiO2-B2O3-Na2O (SBN) have been selected and their hardness, toughness, and stress corrosion cracking behavior have been characterized prior and after irradiation. The comparative study of the non-irradiated SBN glasses provides the role played by the chemical composition. The sodium content is found to be the key parameter: As it increases, the glass plasticity increases, leading to changes in the mechanical response to strain. Hardness (Hv) and toughness (Kc) decrease since the flow under indenter increases. The analysis of the stress corrosion behavior evidences a clear shift of the SCC curves linked also to the glass plasticity. Four of the 8 simplified SBN glass systems highlight the influence of electron, light and heavy ions irradiations on the mechanical properties. Once again, the sodium content is a key parameter. It is found to inhibit the glass modification: Glasses with high sodium content are more stable. Ions irradiations highlight the predominant role of nuclear interaction in changing the glass properties. Finally, electronic interaction induced by helium and electron irradiation does not lead to the same structural/mechanical glasses variations. (author)

  15. Dissolution of cerium(IV)-lanthanide(III) oxides: Comparative effect of chemical composition, temperature, and acidity

    International Nuclear Information System (INIS)

    The dissolution of Ce1-xLnxO2-x/2 solid solutions was undertaken in various acid media in order to evaluate the effects of several physicochemical parameters such as chemical composition, temperature, and acidity on the reaction kinetics. The normalized dissolution rates (RL,0) were found to be strongly modified by the trivalent lanthanide incorporation rate, due to the presence of oxygen vacancies decreasing the samples cohesion. Conversely, the nature of the trivalent cation considered only weakly impacted the RL,0 values. The dependence of the normalized dissolution rates on the temperature then appeared to be of the same order of magnitude than that of chemical composition. Moreover, it allowed determining the corresponding activation energy (EA ≅ 60-85 kJ.mol-1) which accounts for a dissolution driven by surface-controlled reactions. A similar conclusion was made regarding the acidity of the solution: the partial order related to (H3O+) reaching about 0.7. Finally, the prevailing effect of the incorporation of aliovalent cations in the fluorite-type CeO2 matrix on the dissolution kinetics precluded the observation of slight effects such as those linked to the complexing agents or to the crystal structure of the samples. (authors)

  16. Changes in chemical composition and antioxidative properties of rye ginger cakes during their shelf-life.

    Science.gov (United States)

    Zieliński, Henryk; del Castillo, Maria Dolores; Przygodzka, Małgorzata; Ciesarova, Zuzana; Kukurova, Kristina; Zielińska, Danuta

    2012-12-15

    Changes in chemical composition and antioxidative properties of rye ginger cakes during their shelf-life were investigated in this study. In particular, the changes in antioxidants content, antioxidative and reducing capacity, and Maillard reaction development in rye ginger cakes after long-term storage were addressed. Ginger cakes produced according to the traditional and current recipe were stored for 5 years at room temperature in a dark place. The total phenolic compounds (TPC), inositol hexaphosphate (IP6), reduced (GSH) and oxidised glutathione (GSSG) contents, antioxidant and reducing capacity and Maillard reaction products (MRPs) were determined in ginger cakes after storage and then compared to those measured after baking. After long-term storage a decrease in TPC and IP6 contents in cakes was noted. In contrast, an increase in antioxidative and reducing capacity of stored cakes was observed. Long-term storage induced formation of furosine, advanced and final Maillard reaction products and caused changes in both reduced and oxidised forms of glutathione. After long-term storage the modest changes in furosine, FAST index and browning in ginger cake formulated with dark rye flour may suggest that this product is the healthiest among others. Therefore, traditional rye ginger cakes can be considered as an example of a healthy food that is also relatively stable during long term storage as noted by the small chemical changes observed in its composition. PMID:22980898

  17. Gradients in dust chemical composition in protoplanetary disks: analogies with the Solar System

    Science.gov (United States)

    Riaz, Basmah; Kelley, M.; Campins, H.

    2014-11-01

    Clues to planet-forming processes are provided by the properties of the dust grains in protoplanetary disks and in cometary nuclei in our own Solar System. We present a compositional analysis of the 10µm and 20µm silicate emission features for young protoplanetary disks around FGKM stars. We find an increase in the crystallinity levels towards larger radii, such that the median crystalline mass fraction is higher in the outer cold disk region compared to the inner warm parts of the disk. For nearly 80% of the disks, the mass fraction of small ISM-like dust grains is negligible (analogy to comets. In this context, we will discuss the applicability of the various mechanisms that have been proposed for comets on the formation and the outward transport of high-temperature material. A (weak) anti-correlation between the X-ray emission strength and the extent of crystallinity in the disk is observed, suggesting X-rays to be an important dust amorphization agent in these disks. This work has highlighted the ubiquity of Solar System like chemical signatures in young protoplanetary disks, and suggests that protoplanets that form closer to a low-mass star can have a different chemical composition from those that formed farther away.

  18. Effects of aerosol sources and chemical compositions on cloud drop sizes and glaciation temperatures

    Science.gov (United States)

    Zipori, Assaf; Rosenfeld, Daniel; Tirosh, Ofir; Teutsch, Nadya; Erel, Yigal

    2015-09-01

    The effect of aerosols on cloud properties, such as its droplet sizes and its glaciation temperatures, depends on their compositions and concentrations. In order to examine these effects, we collected rain samples in northern Israel during five winters (2008-2011 and 2013) and determined their chemical composition, which was later used to identify the aerosols' sources. By combining the chemical data with satellite-retrieved cloud properties, we linked the aerosol types, sources, and concentrations with the cloud glaciation temperatures (Tg). The presence of dust increased Tg from -26°C to -12°C already at relatively low dust concentrations. This result is in agreement with the conventional wisdom that desert dust serves as good ice nuclei (INs). With higher dust concentrations, Tg saturated at -12°C, even though cloud droplet sizes decreased as a result of the cloud condensation nucleating (CCN) activity of the dust. Marine air masses also encouraged freezing, but in this case, freezing was enhanced by the larger cloud droplet sizes in the air masses (caused by low CCN concentrations) and not by IN concentrations or by aerosol type. An increased fraction of anthropogenic aerosols in marine air masses caused a decrease in Tg, indicating that these aerosols served as poor IN. Anthropogenic aerosols reduced cloud droplet sizes, which further decreased Tg. Our results could be useful in climate models for aerosol-cloud interactions, as we investigated the effects of aerosols of different sources on cloud properties. Such parameterization can simplify these models substantially.

  19. Chemical analyses and calculation of isotopic compositions of high-burnup UO2 fuels and MOX fuels

    International Nuclear Information System (INIS)

    Chemical analysis activities of isotopic compositions of high-burnup UO2 fuels and MOX fuels in CRIEPI and calculation evaluation are reviewed briefly. C/E values of ORIGEN2, in which original libraries and JENDL-3.2 libraries are used, and other codes with chemical analysis data are reviewed and evaluated. Isotopic compositions of main U and Pu in fuels can be evaluated within 10% relative errors by suitable libraries and codes. Void ratio is effective parameter for C/E values in BWR fuels. JENDL-3.2 library shows remarkable improvement compared with original libraries in isotopic composition evaluations of FP nuclides. (author)

  20. Determination of the chemical composition of distorted InGaN/GaN heterostructures from x-ray diffraction data

    International Nuclear Information System (INIS)

    An evaluation algorithm for the determination of the chemical composition of strained hexagonal epitaxial films is presented. This algorithm is able to separate the influence of strain and composition on the lattice parameters measured by x-ray diffraction. The measurement of symmetric and asymmetric reflections delivers the strained lattice parameters a and c of hexagonal epitaxial films. These lattice parameters are used to calculate the relaxed lattice parameters employing the theory of elasticity. From the relaxed parameters, the chemical composition of the epitaxial film can be determined by Vegard's rule. The algorithm has been applied to InGaN/GaN/Al2O3(00.1) heterostructures. (author)