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Sample records for carbazones

  1. Oxo-halogen complexes of molybdenum (V) with bioactive polyfunctional organic ligands

    International Nuclear Information System (INIS)

    Azizkulova, O.A.

    1997-01-01

    The present work dedicated to systematization of synthesized by author coordinated compounds of molybdenum with aminoacetic, asparaginic, glutamic, n-aminobenzoic acids, 1-methyl-2-imidazole, thio-semi-carbazone, thia-dia-zole and its derivatives each of which has from 2 till 5 potentially donor atom

  2. Zinc distribution and localization in primed maize seeds and its translocation during early seedling development

    DEFF Research Database (Denmark)

    Imran, Muhammad; Garbe-Schönberg, Dieter; Neumann, Günter

    2017-01-01

    Zinc (Zn) priming is a technique used to increase seed Zn reserves for improving seed quality, crop growth, and enhancing stress tolerance in crop plants. The present study demonstrated the effect of water and Zn priming on the distribution and accumulation of endogenous and primed Zn in maize...... seeds (Zea mays L.). Zn concentration in unprimed, water and Zn primed seeds and germinated seedlings were analyzed by ICP-MS (Inductivity Coupled Plasma Mass Spectroscopy). DTZ (Diphenyle Thio-Carbazone) staining method and LA-ICP-MS (Laser Ablation Inductivity Coupled Plasma Mass Spectroscopy...

  3. Comparison of sampling methods for radiocarbon dating of carbonyls in air samples via accelerator mass spectrometry

    Science.gov (United States)

    Schindler, Matthias; Kretschmer, Wolfgang; Scharf, Andreas; Tschekalinskij, Alexander

    2016-05-01

    Three new methods to sample and prepare various carbonyl compounds for radiocarbon measurements were developed and tested. Two of these procedures utilized the Strecker synthetic method to form amino acids from carbonyl compounds with either sodium cyanide or trimethylsilyl cyanide. The third procedure used semicarbazide to form crystalline carbazones with the carbonyl compounds. The resulting amino acids and semicarbazones were then separated and purified using thin layer chromatography. The separated compounds were then combusted to CO2 and reduced to graphite to determine 14C content by accelerator mass spectrometry (AMS). All of these methods were also compared with the standard carbonyl compound sampling method wherein a compound is derivatized with 2,4-dinitrophenylhydrazine and then separated by high-performance liquid chromatography (HPLC).

  4. Comparison of sampling methods for radiocarbon dating of carbonyls in air samples via accelerator mass spectrometry

    Energy Technology Data Exchange (ETDEWEB)

    Schindler, Matthias, E-mail: matthias.schindler@physik.uni-erlangen.de; Kretschmer, Wolfgang; Scharf, Andreas; Tschekalinskij, Alexander

    2016-05-15

    Three new methods to sample and prepare various carbonyl compounds for radiocarbon measurements were developed and tested. Two of these procedures utilized the Strecker synthetic method to form amino acids from carbonyl compounds with either sodium cyanide or trimethylsilyl cyanide. The third procedure used semicarbazide to form crystalline carbazones with the carbonyl compounds. The resulting amino acids and semicarbazones were then separated and purified using thin layer chromatography. The separated compounds were then combusted to CO{sub 2} and reduced to graphite to determine {sup 14}C content by accelerator mass spectrometry (AMS). All of these methods were also compared with the standard carbonyl compound sampling method wherein a compound is derivatized with 2,4-dinitrophenylhydrazine and then separated by high-performance liquid chromatography (HPLC).

  5. Preparation of modified magnetic nanoparticles as a sorbent for the preconcentration and determination of cadmium ions in food and environmental water samples prior to flame atomic absorption spectrometry

    Energy Technology Data Exchange (ETDEWEB)

    Mirabi, Ali; Dalirandeh, Zeinab [Department of Chemistry, Qaemshahr Branch, Islamic Azad University, Qaemshahr (Iran, Islamic Republic of); Rad, Ali Shokuhi, E-mail: a.shokuhi@qaemshahriau.ac.ir [Department of Chemical Engineering, Qaemshahr Branch, Islamic Azad University, Qaemshahr (Iran, Islamic Republic of)

    2015-05-01

    A new method has been developed for the separation/preconcentration of trace level cadmium ions using diphenyl carbazone/sodium dodecyl sulfate immobilized on magnetic nanoparticle Fe{sub 3}O{sub 4} as a new sorbent SPE and their determination by flame atomic absorption spectrometry (FAAS). Synthesized nanoparticle was characterized by scanning electron microscope (SEM) and transmission electron microscope (TEM). Various influencing parameters on the separation and preconcentration of trace level cadmium ions such as, pH value, amount of nanoparticles, amount of diphenyl carbazone, condition of eluting solution, the effects of matrix ions were examined. The cadmium ions can be eluted from the modified magnetic nanoparticle using 1 mol L{sup −1} HCl as a desorption reagent. The detection limit of this method for cadmium was 3.71 ng ml{sup −1} and the R.S.D. was 0.503% (n=6). The advantages of this new method include rapidity, easy preparation of sorbents and a high concentration factor. The proposed method has been applied to the determination of Cd ions at trace levels in real samples such as, green tea, rice, tobacco, carrot, lettuce, ginseng, spice, tap water, river water, sea water with satisfactory results. - Highlights: • MNPs method is economical, simple, rapid and sensitive for trace analysis of Cd. • High preconcentration factor was obtained easily through this method. • A detection limit at ng mL{sup −1} level was achieved with 100.0 mL of sample. • This method provides good repeatability and extraction efficiency in a short time.

  6. Preparation of modified magnetic nanoparticles as a sorbent for the preconcentration and determination of cadmium ions in food and environmental water samples prior to flame atomic absorption spectrometry

    International Nuclear Information System (INIS)

    Mirabi, Ali; Dalirandeh, Zeinab; Rad, Ali Shokuhi

    2015-01-01

    A new method has been developed for the separation/preconcentration of trace level cadmium ions using diphenyl carbazone/sodium dodecyl sulfate immobilized on magnetic nanoparticle Fe 3 O 4 as a new sorbent SPE and their determination by flame atomic absorption spectrometry (FAAS). Synthesized nanoparticle was characterized by scanning electron microscope (SEM) and transmission electron microscope (TEM). Various influencing parameters on the separation and preconcentration of trace level cadmium ions such as, pH value, amount of nanoparticles, amount of diphenyl carbazone, condition of eluting solution, the effects of matrix ions were examined. The cadmium ions can be eluted from the modified magnetic nanoparticle using 1 mol L −1 HCl as a desorption reagent. The detection limit of this method for cadmium was 3.71 ng ml −1 and the R.S.D. was 0.503% (n=6). The advantages of this new method include rapidity, easy preparation of sorbents and a high concentration factor. The proposed method has been applied to the determination of Cd ions at trace levels in real samples such as, green tea, rice, tobacco, carrot, lettuce, ginseng, spice, tap water, river water, sea water with satisfactory results. - Highlights: • MNPs method is economical, simple, rapid and sensitive for trace analysis of Cd. • High preconcentration factor was obtained easily through this method. • A detection limit at ng mL −1 level was achieved with 100.0 mL of sample. • This method provides good repeatability and extraction efficiency in a short time

  7. Properties of photocatalytically generated oxygen species produced by Ag2Se-graphene oxide heterojunction and its application for the visible-light degradation of ammonia

    Science.gov (United States)

    Meng, Ze-Da; Zhao, Wei; Kim, Sukyoung

    2017-11-01

    Reactive oxygen species (ROS) can be produced by the interactions between sunlight and light-absorbing substances in aqueous environments, and these ROS are capable of destroying various organic pollutants in wastewater. In this study, the photocatalytic degradation of ammonia in petrochemical wastewater was investigated by solar light photocatalysis. We used graphene oxide modified Ag2Se nanoparticles to enhance the activity of photochemically generated oxygen (PGO) species. There was a catastrophic decrease in the surface area and pore volume of the Ag2Se-graphene oxide (Ag2Se-G) samples because of the deposition of Ag2Se. The generation of ROS was detected by the oxidation of 1,5- diphenyl carbazide (DPCI) to 1,5-diphenyl carbazone (DPCO). It was revealed that the photocurrent density and PGO effect increased with the graphene oxide modified. The experimental results indicate that this heterogeneous catalyst achieved a degradation of 88.43% under visiblelight irradiation. The NH3 degradation product was N2 and neither NO2- nor NO3- were detected.[Figure not available: see fulltext.

  8. Simultaneous quantification of preactivated ifosfamide derivatives and of 4-hydroxyifosfamide by high performance liquid chromatography-tandem mass spectrometry in mouse plasma and its application to a pharmacokinetic study.

    Science.gov (United States)

    Deroussent, Alain; Skarbek, Charles; Maury, Adeline; Chapuis, Hubert; Daudigeos-Dubus, Estelle; Le Dret, Ludivine; Durand, Sylvère; Couvreur, Patrick; Desmaële, Didier; Paci, Angelo

    2015-06-15

    The antitumor drug, ifosfamide (IFO), requires activation by cytochrome P450 (CYP) to form the active metabolite, 4-hydroxyisfosfamide (4-OHIFO), leading to toxic by-products at high dose. In order to overcome these drawbacks, preactivated ifosfamide derivatives (RXIFO) were designed to release 4-OHIFO without CYP involvement. A high performance liquid chromatography-tandem mass spectrometry (HPLC-MS/MS) method was developed for the simultaneous quantification of 4-OHIFO, IFO and four derivatives RXIFO in mouse plasma using multiple reaction monitoring. Because of its instability in plasma, 4-OHIFO was immediately converted to the semi-carbazone derivative, 4-OHIFO-SCZ. For the six analytes, the calibration curves were linear from 20 to 5000ng/mL in 50μL plasma and the lower limit of quantitation was determined at 20ng/mL with accuracies within ±10% of nominal and precisions less than 12%. Their recoveries ranged from 62 to 96% by using liquid-liquid extraction. With an improved assay sensitivity compared to analogues, the derivative 4-OHIFO-SCZ was stable in plasma at 4°C for 24h and at -20°C for three months. For all compounds, the assay was validated with accuracies within ±13% and precisions less than 15%. This method was applied to a comparative pharmacokinetic study of 4-OHIFO from IFO and three derivatives RXIFO in mice. This active metabolite was produced by some of the novel conjugates with good pharmacokinetic properties. Copyright © 2015 Elsevier B.V. All rights reserved.

  9. Confirmation of hydroxyl radicals ({sup •} OH) generated in the presence of TiO{sub 2} supported on AC under microwave irradiation

    Energy Technology Data Exchange (ETDEWEB)

    Zhang, Zhaohong, E-mail: lnuhjhx@163.com [School of Environmental Science, Liaoning University, Shenyang 110036 (China); Yu, Fengyang; Huang, Lirong; Jiatieli, Jianaerguli; Li, Yuanyuan; Song, Lijun [School of Environmental Science, Liaoning University, Shenyang 110036 (China); Yu, Ning [Experiment Center of Environmental Monitoring of Liaoning Province, Shenyang 110161 (China); Dionysiou, Dionysios D., E-mail: dionysios.d.dionysiou@uc.edu [Environmental Engineering and Science Program, University of Cincinnati, Cincinnati, OH 45221-0012 (United States)

    2014-08-15

    Graphical abstract: - Highlights: • Generation of {sup •} OH in MW integrated with loaded TiO{sub 2}/AC system was confirmed. • Confirmation of {sup •} OH was conducted using radical scavenger such as BHT, MT and VC. • More {sup •} OH was formed using anatase TiO{sub 2}/AC than rutile TiO{sub 2}/AC under MW irradiation. • Effect of mass ratio, irradiation time, catalyst dose and DPCI on {sup •} OH was studied. - Abstract: In order to study the degradation mechanism of technology of microwave (MW) combined with TiO{sub 2} supported on activated carbon (TiO{sub 2}/AC), the reactive oxygen species (ROS) was explored through oxidation of 1,5-diphenyl carbazide (DPCI) to 1,5-diphenyl carbazone (DPCO). Furthermore, 2,6-di-tert-butyl-4-methylphenol (BHT), Mannitol (MT) and Vitamin C (VC) were used as radical scavengers to confirm the generation of the hydroxyl radicals ({sup •} OH). In addition, the influence of some parameters such as TiO{sub 2} mass ratio content, irradiation time, material dose, DPCI concentration and MW power on the determination of {sup •} OH were examined. The results showed that the {sup •} OH could be generated under MW combined with loaded TiO{sub 2}/AC. Also, anatase TiO{sub 2}/AC can generate more {sup •} OH radicals than rutile TiO{sub 2}/AC under MW irradiation. This work would provide new mechanistic insights on the enhanced degradation effect of organic pollutants in water using the supported TiO{sub 2}/AC coupled with MW technology.

  10. Intratumoral distribution of CU-ATSM and FDG: immunohistochemical characterization of the region with high CU-ATSM or FDG accumulation

    Energy Technology Data Exchange (ETDEWEB)

    Takako, Furukawa; Tsuneo, Saga; Yasuhisa, Fujibayashi [Institute of Radiological Sciences, Dept. of Diagnostic Imaging, Molecular Imaging Center, Nationa, Chiba (Japan); Takako, Furukawa; Takeshi, Tanaka; Yasuhisa, Fujibayashi [Fukui Univ., Biomedica Imaging Research Center (Japan)

    2006-07-01

    Intratumoral distribution of [Cu-64]Cu-di-acetyl-bis (N4-methyl-thio-semi-carbazone ) ({sup 64}Cu-ATSM) and fluorine-18 2-fluoro-2-deoxyglucose ({sup 18}FDG) in mice bearing tumors of four different origins, LLC1 (Lewis lung carcinoma), Meth-A (sarcoma), B16 (melanoma) and colon26 (adenocarcinoma), were compared to the immunohistochemical staining for proliferating cells (Ki67), blood vessels (CD34 or von Willebrand Factor (vWF)) and apoptotic cells (terminal deoxynucleotidyl transferase (TdT)-mediated dUTP nick end labeling (TUNEL) method). With all the cell lines, {sup 64}Cu-ATSM and {sup 18}FDG were distributed to different regions of the tumor mass. The immunohistochemical study demonstrated that the high {sup 64}Cu-ASTM uptake regions were hypo-vascular and consisted of tumor cells arrested in cell cycle, while the high {sup 18}FGD uptake regions were hyper-vascular and consisted of proliferating cells. Through our study, it was revealed that one tumor mass contains two regions of different characteristics, which can be distinguished by {sup 64}Cu-ATSM and {sup 18}FDG. Since hypoxia and cell cycle arrest are critical factors to reduce the sensitivity of tumor to radiation and conventional chemotherapy, regions with such characteristics in tumor should be treated intensively as one of the primary targets. {sup 64}Cu-ATSM which can delineate hypoxic and cell cycle arrested regions in tumors can provide valuable information for cancer treatment as well as the possibility to treat such regions directly as an internal radiotherapy reagent. (author)